Commit | Line | Data |
---|---|---|
457c8996 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * Generic hugetlb support. | |
6d49e352 | 4 | * (C) Nadia Yvette Chambers, April 2004 |
1da177e4 | 5 | */ |
1da177e4 LT |
6 | #include <linux/list.h> |
7 | #include <linux/init.h> | |
1da177e4 | 8 | #include <linux/mm.h> |
e1759c21 | 9 | #include <linux/seq_file.h> |
1da177e4 LT |
10 | #include <linux/sysctl.h> |
11 | #include <linux/highmem.h> | |
cddb8a5c | 12 | #include <linux/mmu_notifier.h> |
1da177e4 | 13 | #include <linux/nodemask.h> |
63551ae0 | 14 | #include <linux/pagemap.h> |
5da7ca86 | 15 | #include <linux/mempolicy.h> |
3b32123d | 16 | #include <linux/compiler.h> |
aea47ff3 | 17 | #include <linux/cpuset.h> |
3935baa9 | 18 | #include <linux/mutex.h> |
97ad1087 | 19 | #include <linux/memblock.h> |
a3437870 | 20 | #include <linux/sysfs.h> |
5a0e3ad6 | 21 | #include <linux/slab.h> |
bbe88753 | 22 | #include <linux/sched/mm.h> |
63489f8e | 23 | #include <linux/mmdebug.h> |
174cd4b1 | 24 | #include <linux/sched/signal.h> |
0fe6e20b | 25 | #include <linux/rmap.h> |
c6247f72 | 26 | #include <linux/string_helpers.h> |
fd6a03ed NH |
27 | #include <linux/swap.h> |
28 | #include <linux/swapops.h> | |
8382d914 | 29 | #include <linux/jhash.h> |
98fa15f3 | 30 | #include <linux/numa.h> |
c77c0a8a | 31 | #include <linux/llist.h> |
cf11e85f | 32 | #include <linux/cma.h> |
8cc5fcbb | 33 | #include <linux/migrate.h> |
f9317f77 | 34 | #include <linux/nospec.h> |
662ce1dc | 35 | #include <linux/delayacct.h> |
b958d4d0 | 36 | #include <linux/memory.h> |
af19487f | 37 | #include <linux/mm_inline.h> |
c6c21c31 | 38 | #include <linux/padata.h> |
d6606683 | 39 | |
63551ae0 | 40 | #include <asm/page.h> |
ca15ca40 | 41 | #include <asm/pgalloc.h> |
24669e58 | 42 | #include <asm/tlb.h> |
63551ae0 | 43 | |
24669e58 | 44 | #include <linux/io.h> |
63551ae0 | 45 | #include <linux/hugetlb.h> |
9dd540e2 | 46 | #include <linux/hugetlb_cgroup.h> |
9a305230 | 47 | #include <linux/node.h> |
ab5ac90a | 48 | #include <linux/page_owner.h> |
7835e98b | 49 | #include "internal.h" |
f41f2ed4 | 50 | #include "hugetlb_vmemmap.h" |
1da177e4 | 51 | |
c3f38a38 | 52 | int hugetlb_max_hstate __read_mostly; |
e5ff2159 AK |
53 | unsigned int default_hstate_idx; |
54 | struct hstate hstates[HUGE_MAX_HSTATE]; | |
cf11e85f | 55 | |
dbda8fea | 56 | #ifdef CONFIG_CMA |
cf11e85f | 57 | static struct cma *hugetlb_cma[MAX_NUMNODES]; |
38e719ab | 58 | static unsigned long hugetlb_cma_size_in_node[MAX_NUMNODES] __initdata; |
2f6c57d6 | 59 | static bool hugetlb_cma_folio(struct folio *folio, unsigned int order) |
a01f4390 | 60 | { |
2f6c57d6 | 61 | return cma_pages_valid(hugetlb_cma[folio_nid(folio)], &folio->page, |
a01f4390 MK |
62 | 1 << order); |
63 | } | |
64 | #else | |
2f6c57d6 | 65 | static bool hugetlb_cma_folio(struct folio *folio, unsigned int order) |
a01f4390 MK |
66 | { |
67 | return false; | |
68 | } | |
dbda8fea BS |
69 | #endif |
70 | static unsigned long hugetlb_cma_size __initdata; | |
cf11e85f | 71 | |
b78b27d0 | 72 | __initdata struct list_head huge_boot_pages[MAX_NUMNODES]; |
53ba51d2 | 73 | |
e5ff2159 AK |
74 | /* for command line parsing */ |
75 | static struct hstate * __initdata parsed_hstate; | |
76 | static unsigned long __initdata default_hstate_max_huge_pages; | |
9fee021d | 77 | static bool __initdata parsed_valid_hugepagesz = true; |
282f4214 | 78 | static bool __initdata parsed_default_hugepagesz; |
b5389086 | 79 | static unsigned int default_hugepages_in_node[MAX_NUMNODES] __initdata; |
e5ff2159 | 80 | |
3935baa9 | 81 | /* |
31caf665 NH |
82 | * Protects updates to hugepage_freelists, hugepage_activelist, nr_huge_pages, |
83 | * free_huge_pages, and surplus_huge_pages. | |
3935baa9 | 84 | */ |
c3f38a38 | 85 | DEFINE_SPINLOCK(hugetlb_lock); |
0bd0f9fb | 86 | |
8382d914 DB |
87 | /* |
88 | * Serializes faults on the same logical page. This is used to | |
89 | * prevent spurious OOMs when the hugepage pool is fully utilized. | |
90 | */ | |
91 | static int num_fault_mutexes; | |
c672c7f2 | 92 | struct mutex *hugetlb_fault_mutex_table ____cacheline_aligned_in_smp; |
8382d914 | 93 | |
7ca02d0a MK |
94 | /* Forward declaration */ |
95 | static int hugetlb_acct_memory(struct hstate *h, long delta); | |
8d9bfb26 MK |
96 | static void hugetlb_vma_lock_free(struct vm_area_struct *vma); |
97 | static void hugetlb_vma_lock_alloc(struct vm_area_struct *vma); | |
ecfbd733 | 98 | static void __hugetlb_vma_unlock_write_free(struct vm_area_struct *vma); |
b30c14cd JH |
99 | static void hugetlb_unshare_pmds(struct vm_area_struct *vma, |
100 | unsigned long start, unsigned long end); | |
bf491692 | 101 | static struct resv_map *vma_resv_map(struct vm_area_struct *vma); |
7ca02d0a | 102 | |
1d88433b | 103 | static inline bool subpool_is_free(struct hugepage_subpool *spool) |
90481622 | 104 | { |
1d88433b ML |
105 | if (spool->count) |
106 | return false; | |
107 | if (spool->max_hpages != -1) | |
108 | return spool->used_hpages == 0; | |
109 | if (spool->min_hpages != -1) | |
110 | return spool->rsv_hpages == spool->min_hpages; | |
111 | ||
112 | return true; | |
113 | } | |
90481622 | 114 | |
db71ef79 MK |
115 | static inline void unlock_or_release_subpool(struct hugepage_subpool *spool, |
116 | unsigned long irq_flags) | |
1d88433b | 117 | { |
db71ef79 | 118 | spin_unlock_irqrestore(&spool->lock, irq_flags); |
90481622 DG |
119 | |
120 | /* If no pages are used, and no other handles to the subpool | |
7c8de358 | 121 | * remain, give up any reservations based on minimum size and |
7ca02d0a | 122 | * free the subpool */ |
1d88433b | 123 | if (subpool_is_free(spool)) { |
7ca02d0a MK |
124 | if (spool->min_hpages != -1) |
125 | hugetlb_acct_memory(spool->hstate, | |
126 | -spool->min_hpages); | |
90481622 | 127 | kfree(spool); |
7ca02d0a | 128 | } |
90481622 DG |
129 | } |
130 | ||
7ca02d0a MK |
131 | struct hugepage_subpool *hugepage_new_subpool(struct hstate *h, long max_hpages, |
132 | long min_hpages) | |
90481622 DG |
133 | { |
134 | struct hugepage_subpool *spool; | |
135 | ||
c6a91820 | 136 | spool = kzalloc(sizeof(*spool), GFP_KERNEL); |
90481622 DG |
137 | if (!spool) |
138 | return NULL; | |
139 | ||
140 | spin_lock_init(&spool->lock); | |
141 | spool->count = 1; | |
7ca02d0a MK |
142 | spool->max_hpages = max_hpages; |
143 | spool->hstate = h; | |
144 | spool->min_hpages = min_hpages; | |
145 | ||
146 | if (min_hpages != -1 && hugetlb_acct_memory(h, min_hpages)) { | |
147 | kfree(spool); | |
148 | return NULL; | |
149 | } | |
150 | spool->rsv_hpages = min_hpages; | |
90481622 DG |
151 | |
152 | return spool; | |
153 | } | |
154 | ||
155 | void hugepage_put_subpool(struct hugepage_subpool *spool) | |
156 | { | |
db71ef79 MK |
157 | unsigned long flags; |
158 | ||
159 | spin_lock_irqsave(&spool->lock, flags); | |
90481622 DG |
160 | BUG_ON(!spool->count); |
161 | spool->count--; | |
db71ef79 | 162 | unlock_or_release_subpool(spool, flags); |
90481622 DG |
163 | } |
164 | ||
1c5ecae3 MK |
165 | /* |
166 | * Subpool accounting for allocating and reserving pages. | |
167 | * Return -ENOMEM if there are not enough resources to satisfy the | |
9e7ee400 | 168 | * request. Otherwise, return the number of pages by which the |
1c5ecae3 MK |
169 | * global pools must be adjusted (upward). The returned value may |
170 | * only be different than the passed value (delta) in the case where | |
7c8de358 | 171 | * a subpool minimum size must be maintained. |
1c5ecae3 MK |
172 | */ |
173 | static long hugepage_subpool_get_pages(struct hugepage_subpool *spool, | |
90481622 DG |
174 | long delta) |
175 | { | |
1c5ecae3 | 176 | long ret = delta; |
90481622 DG |
177 | |
178 | if (!spool) | |
1c5ecae3 | 179 | return ret; |
90481622 | 180 | |
db71ef79 | 181 | spin_lock_irq(&spool->lock); |
1c5ecae3 MK |
182 | |
183 | if (spool->max_hpages != -1) { /* maximum size accounting */ | |
184 | if ((spool->used_hpages + delta) <= spool->max_hpages) | |
185 | spool->used_hpages += delta; | |
186 | else { | |
187 | ret = -ENOMEM; | |
188 | goto unlock_ret; | |
189 | } | |
90481622 | 190 | } |
90481622 | 191 | |
09a95e29 MK |
192 | /* minimum size accounting */ |
193 | if (spool->min_hpages != -1 && spool->rsv_hpages) { | |
1c5ecae3 MK |
194 | if (delta > spool->rsv_hpages) { |
195 | /* | |
196 | * Asking for more reserves than those already taken on | |
197 | * behalf of subpool. Return difference. | |
198 | */ | |
199 | ret = delta - spool->rsv_hpages; | |
200 | spool->rsv_hpages = 0; | |
201 | } else { | |
202 | ret = 0; /* reserves already accounted for */ | |
203 | spool->rsv_hpages -= delta; | |
204 | } | |
205 | } | |
206 | ||
207 | unlock_ret: | |
db71ef79 | 208 | spin_unlock_irq(&spool->lock); |
90481622 DG |
209 | return ret; |
210 | } | |
211 | ||
1c5ecae3 MK |
212 | /* |
213 | * Subpool accounting for freeing and unreserving pages. | |
214 | * Return the number of global page reservations that must be dropped. | |
215 | * The return value may only be different than the passed value (delta) | |
216 | * in the case where a subpool minimum size must be maintained. | |
217 | */ | |
218 | static long hugepage_subpool_put_pages(struct hugepage_subpool *spool, | |
90481622 DG |
219 | long delta) |
220 | { | |
1c5ecae3 | 221 | long ret = delta; |
db71ef79 | 222 | unsigned long flags; |
1c5ecae3 | 223 | |
90481622 | 224 | if (!spool) |
1c5ecae3 | 225 | return delta; |
90481622 | 226 | |
db71ef79 | 227 | spin_lock_irqsave(&spool->lock, flags); |
1c5ecae3 MK |
228 | |
229 | if (spool->max_hpages != -1) /* maximum size accounting */ | |
230 | spool->used_hpages -= delta; | |
231 | ||
09a95e29 MK |
232 | /* minimum size accounting */ |
233 | if (spool->min_hpages != -1 && spool->used_hpages < spool->min_hpages) { | |
1c5ecae3 MK |
234 | if (spool->rsv_hpages + delta <= spool->min_hpages) |
235 | ret = 0; | |
236 | else | |
237 | ret = spool->rsv_hpages + delta - spool->min_hpages; | |
238 | ||
239 | spool->rsv_hpages += delta; | |
240 | if (spool->rsv_hpages > spool->min_hpages) | |
241 | spool->rsv_hpages = spool->min_hpages; | |
242 | } | |
243 | ||
244 | /* | |
245 | * If hugetlbfs_put_super couldn't free spool due to an outstanding | |
246 | * quota reference, free it now. | |
247 | */ | |
db71ef79 | 248 | unlock_or_release_subpool(spool, flags); |
1c5ecae3 MK |
249 | |
250 | return ret; | |
90481622 DG |
251 | } |
252 | ||
253 | static inline struct hugepage_subpool *subpool_inode(struct inode *inode) | |
254 | { | |
255 | return HUGETLBFS_SB(inode->i_sb)->spool; | |
256 | } | |
257 | ||
258 | static inline struct hugepage_subpool *subpool_vma(struct vm_area_struct *vma) | |
259 | { | |
496ad9aa | 260 | return subpool_inode(file_inode(vma->vm_file)); |
90481622 DG |
261 | } |
262 | ||
e700898f MK |
263 | /* |
264 | * hugetlb vma_lock helper routines | |
265 | */ | |
e700898f MK |
266 | void hugetlb_vma_lock_read(struct vm_area_struct *vma) |
267 | { | |
268 | if (__vma_shareable_lock(vma)) { | |
269 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
270 | ||
271 | down_read(&vma_lock->rw_sema); | |
bf491692 RR |
272 | } else if (__vma_private_lock(vma)) { |
273 | struct resv_map *resv_map = vma_resv_map(vma); | |
274 | ||
275 | down_read(&resv_map->rw_sema); | |
e700898f MK |
276 | } |
277 | } | |
278 | ||
279 | void hugetlb_vma_unlock_read(struct vm_area_struct *vma) | |
280 | { | |
281 | if (__vma_shareable_lock(vma)) { | |
282 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
283 | ||
284 | up_read(&vma_lock->rw_sema); | |
bf491692 RR |
285 | } else if (__vma_private_lock(vma)) { |
286 | struct resv_map *resv_map = vma_resv_map(vma); | |
287 | ||
288 | up_read(&resv_map->rw_sema); | |
e700898f MK |
289 | } |
290 | } | |
291 | ||
292 | void hugetlb_vma_lock_write(struct vm_area_struct *vma) | |
293 | { | |
294 | if (__vma_shareable_lock(vma)) { | |
295 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
296 | ||
297 | down_write(&vma_lock->rw_sema); | |
bf491692 RR |
298 | } else if (__vma_private_lock(vma)) { |
299 | struct resv_map *resv_map = vma_resv_map(vma); | |
300 | ||
301 | down_write(&resv_map->rw_sema); | |
e700898f MK |
302 | } |
303 | } | |
304 | ||
305 | void hugetlb_vma_unlock_write(struct vm_area_struct *vma) | |
306 | { | |
307 | if (__vma_shareable_lock(vma)) { | |
308 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
309 | ||
310 | up_write(&vma_lock->rw_sema); | |
bf491692 RR |
311 | } else if (__vma_private_lock(vma)) { |
312 | struct resv_map *resv_map = vma_resv_map(vma); | |
313 | ||
314 | up_write(&resv_map->rw_sema); | |
e700898f MK |
315 | } |
316 | } | |
317 | ||
318 | int hugetlb_vma_trylock_write(struct vm_area_struct *vma) | |
319 | { | |
e700898f | 320 | |
bf491692 RR |
321 | if (__vma_shareable_lock(vma)) { |
322 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
e700898f | 323 | |
bf491692 RR |
324 | return down_write_trylock(&vma_lock->rw_sema); |
325 | } else if (__vma_private_lock(vma)) { | |
326 | struct resv_map *resv_map = vma_resv_map(vma); | |
327 | ||
328 | return down_write_trylock(&resv_map->rw_sema); | |
329 | } | |
330 | ||
331 | return 1; | |
e700898f MK |
332 | } |
333 | ||
334 | void hugetlb_vma_assert_locked(struct vm_area_struct *vma) | |
335 | { | |
336 | if (__vma_shareable_lock(vma)) { | |
337 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
338 | ||
339 | lockdep_assert_held(&vma_lock->rw_sema); | |
bf491692 RR |
340 | } else if (__vma_private_lock(vma)) { |
341 | struct resv_map *resv_map = vma_resv_map(vma); | |
342 | ||
343 | lockdep_assert_held(&resv_map->rw_sema); | |
e700898f MK |
344 | } |
345 | } | |
346 | ||
347 | void hugetlb_vma_lock_release(struct kref *kref) | |
348 | { | |
349 | struct hugetlb_vma_lock *vma_lock = container_of(kref, | |
350 | struct hugetlb_vma_lock, refs); | |
351 | ||
352 | kfree(vma_lock); | |
353 | } | |
354 | ||
355 | static void __hugetlb_vma_unlock_write_put(struct hugetlb_vma_lock *vma_lock) | |
356 | { | |
357 | struct vm_area_struct *vma = vma_lock->vma; | |
358 | ||
359 | /* | |
360 | * vma_lock structure may or not be released as a result of put, | |
361 | * it certainly will no longer be attached to vma so clear pointer. | |
362 | * Semaphore synchronizes access to vma_lock->vma field. | |
363 | */ | |
364 | vma_lock->vma = NULL; | |
365 | vma->vm_private_data = NULL; | |
366 | up_write(&vma_lock->rw_sema); | |
367 | kref_put(&vma_lock->refs, hugetlb_vma_lock_release); | |
368 | } | |
369 | ||
370 | static void __hugetlb_vma_unlock_write_free(struct vm_area_struct *vma) | |
371 | { | |
372 | if (__vma_shareable_lock(vma)) { | |
373 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
374 | ||
375 | __hugetlb_vma_unlock_write_put(vma_lock); | |
bf491692 RR |
376 | } else if (__vma_private_lock(vma)) { |
377 | struct resv_map *resv_map = vma_resv_map(vma); | |
378 | ||
379 | /* no free for anon vmas, but still need to unlock */ | |
380 | up_write(&resv_map->rw_sema); | |
e700898f MK |
381 | } |
382 | } | |
383 | ||
384 | static void hugetlb_vma_lock_free(struct vm_area_struct *vma) | |
385 | { | |
386 | /* | |
387 | * Only present in sharable vmas. | |
388 | */ | |
389 | if (!vma || !__vma_shareable_lock(vma)) | |
390 | return; | |
391 | ||
392 | if (vma->vm_private_data) { | |
393 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
394 | ||
395 | down_write(&vma_lock->rw_sema); | |
396 | __hugetlb_vma_unlock_write_put(vma_lock); | |
397 | } | |
398 | } | |
399 | ||
400 | static void hugetlb_vma_lock_alloc(struct vm_area_struct *vma) | |
401 | { | |
402 | struct hugetlb_vma_lock *vma_lock; | |
403 | ||
404 | /* Only establish in (flags) sharable vmas */ | |
405 | if (!vma || !(vma->vm_flags & VM_MAYSHARE)) | |
406 | return; | |
407 | ||
408 | /* Should never get here with non-NULL vm_private_data */ | |
409 | if (vma->vm_private_data) | |
410 | return; | |
411 | ||
412 | vma_lock = kmalloc(sizeof(*vma_lock), GFP_KERNEL); | |
413 | if (!vma_lock) { | |
414 | /* | |
415 | * If we can not allocate structure, then vma can not | |
416 | * participate in pmd sharing. This is only a possible | |
417 | * performance enhancement and memory saving issue. | |
418 | * However, the lock is also used to synchronize page | |
419 | * faults with truncation. If the lock is not present, | |
420 | * unlikely races could leave pages in a file past i_size | |
421 | * until the file is removed. Warn in the unlikely case of | |
422 | * allocation failure. | |
423 | */ | |
424 | pr_warn_once("HugeTLB: unable to allocate vma specific lock\n"); | |
425 | return; | |
426 | } | |
427 | ||
428 | kref_init(&vma_lock->refs); | |
429 | init_rwsem(&vma_lock->rw_sema); | |
430 | vma_lock->vma = vma; | |
431 | vma->vm_private_data = vma_lock; | |
432 | } | |
433 | ||
0db9d74e MA |
434 | /* Helper that removes a struct file_region from the resv_map cache and returns |
435 | * it for use. | |
436 | */ | |
437 | static struct file_region * | |
438 | get_file_region_entry_from_cache(struct resv_map *resv, long from, long to) | |
439 | { | |
3259914f | 440 | struct file_region *nrg; |
0db9d74e MA |
441 | |
442 | VM_BUG_ON(resv->region_cache_count <= 0); | |
443 | ||
444 | resv->region_cache_count--; | |
445 | nrg = list_first_entry(&resv->region_cache, struct file_region, link); | |
0db9d74e MA |
446 | list_del(&nrg->link); |
447 | ||
448 | nrg->from = from; | |
449 | nrg->to = to; | |
450 | ||
451 | return nrg; | |
452 | } | |
453 | ||
075a61d0 MA |
454 | static void copy_hugetlb_cgroup_uncharge_info(struct file_region *nrg, |
455 | struct file_region *rg) | |
456 | { | |
457 | #ifdef CONFIG_CGROUP_HUGETLB | |
458 | nrg->reservation_counter = rg->reservation_counter; | |
459 | nrg->css = rg->css; | |
460 | if (rg->css) | |
461 | css_get(rg->css); | |
462 | #endif | |
463 | } | |
464 | ||
465 | /* Helper that records hugetlb_cgroup uncharge info. */ | |
466 | static void record_hugetlb_cgroup_uncharge_info(struct hugetlb_cgroup *h_cg, | |
467 | struct hstate *h, | |
468 | struct resv_map *resv, | |
469 | struct file_region *nrg) | |
470 | { | |
471 | #ifdef CONFIG_CGROUP_HUGETLB | |
472 | if (h_cg) { | |
473 | nrg->reservation_counter = | |
474 | &h_cg->rsvd_hugepage[hstate_index(h)]; | |
475 | nrg->css = &h_cg->css; | |
d85aecf2 ML |
476 | /* |
477 | * The caller will hold exactly one h_cg->css reference for the | |
478 | * whole contiguous reservation region. But this area might be | |
479 | * scattered when there are already some file_regions reside in | |
480 | * it. As a result, many file_regions may share only one css | |
481 | * reference. In order to ensure that one file_region must hold | |
482 | * exactly one h_cg->css reference, we should do css_get for | |
483 | * each file_region and leave the reference held by caller | |
484 | * untouched. | |
485 | */ | |
486 | css_get(&h_cg->css); | |
075a61d0 MA |
487 | if (!resv->pages_per_hpage) |
488 | resv->pages_per_hpage = pages_per_huge_page(h); | |
489 | /* pages_per_hpage should be the same for all entries in | |
490 | * a resv_map. | |
491 | */ | |
492 | VM_BUG_ON(resv->pages_per_hpage != pages_per_huge_page(h)); | |
493 | } else { | |
494 | nrg->reservation_counter = NULL; | |
495 | nrg->css = NULL; | |
496 | } | |
497 | #endif | |
498 | } | |
499 | ||
d85aecf2 ML |
500 | static void put_uncharge_info(struct file_region *rg) |
501 | { | |
502 | #ifdef CONFIG_CGROUP_HUGETLB | |
503 | if (rg->css) | |
504 | css_put(rg->css); | |
505 | #endif | |
506 | } | |
507 | ||
a9b3f867 MA |
508 | static bool has_same_uncharge_info(struct file_region *rg, |
509 | struct file_region *org) | |
510 | { | |
511 | #ifdef CONFIG_CGROUP_HUGETLB | |
0739eb43 | 512 | return rg->reservation_counter == org->reservation_counter && |
a9b3f867 MA |
513 | rg->css == org->css; |
514 | ||
515 | #else | |
516 | return true; | |
517 | #endif | |
518 | } | |
519 | ||
520 | static void coalesce_file_region(struct resv_map *resv, struct file_region *rg) | |
521 | { | |
3259914f | 522 | struct file_region *nrg, *prg; |
a9b3f867 MA |
523 | |
524 | prg = list_prev_entry(rg, link); | |
525 | if (&prg->link != &resv->regions && prg->to == rg->from && | |
526 | has_same_uncharge_info(prg, rg)) { | |
527 | prg->to = rg->to; | |
528 | ||
529 | list_del(&rg->link); | |
d85aecf2 | 530 | put_uncharge_info(rg); |
a9b3f867 MA |
531 | kfree(rg); |
532 | ||
7db5e7b6 | 533 | rg = prg; |
a9b3f867 MA |
534 | } |
535 | ||
536 | nrg = list_next_entry(rg, link); | |
537 | if (&nrg->link != &resv->regions && nrg->from == rg->to && | |
538 | has_same_uncharge_info(nrg, rg)) { | |
539 | nrg->from = rg->from; | |
540 | ||
541 | list_del(&rg->link); | |
d85aecf2 | 542 | put_uncharge_info(rg); |
a9b3f867 | 543 | kfree(rg); |
a9b3f867 MA |
544 | } |
545 | } | |
546 | ||
2103cf9c | 547 | static inline long |
84448c8e | 548 | hugetlb_resv_map_add(struct resv_map *map, struct list_head *rg, long from, |
2103cf9c PX |
549 | long to, struct hstate *h, struct hugetlb_cgroup *cg, |
550 | long *regions_needed) | |
551 | { | |
552 | struct file_region *nrg; | |
553 | ||
554 | if (!regions_needed) { | |
555 | nrg = get_file_region_entry_from_cache(map, from, to); | |
556 | record_hugetlb_cgroup_uncharge_info(cg, h, map, nrg); | |
84448c8e | 557 | list_add(&nrg->link, rg); |
2103cf9c PX |
558 | coalesce_file_region(map, nrg); |
559 | } else | |
560 | *regions_needed += 1; | |
561 | ||
562 | return to - from; | |
563 | } | |
564 | ||
972a3da3 WY |
565 | /* |
566 | * Must be called with resv->lock held. | |
567 | * | |
568 | * Calling this with regions_needed != NULL will count the number of pages | |
569 | * to be added but will not modify the linked list. And regions_needed will | |
570 | * indicate the number of file_regions needed in the cache to carry out to add | |
571 | * the regions for this range. | |
d75c6af9 MA |
572 | */ |
573 | static long add_reservation_in_range(struct resv_map *resv, long f, long t, | |
075a61d0 | 574 | struct hugetlb_cgroup *h_cg, |
972a3da3 | 575 | struct hstate *h, long *regions_needed) |
d75c6af9 | 576 | { |
0db9d74e | 577 | long add = 0; |
d75c6af9 | 578 | struct list_head *head = &resv->regions; |
0db9d74e | 579 | long last_accounted_offset = f; |
84448c8e JK |
580 | struct file_region *iter, *trg = NULL; |
581 | struct list_head *rg = NULL; | |
d75c6af9 | 582 | |
0db9d74e MA |
583 | if (regions_needed) |
584 | *regions_needed = 0; | |
d75c6af9 | 585 | |
0db9d74e | 586 | /* In this loop, we essentially handle an entry for the range |
84448c8e | 587 | * [last_accounted_offset, iter->from), at every iteration, with some |
0db9d74e MA |
588 | * bounds checking. |
589 | */ | |
84448c8e | 590 | list_for_each_entry_safe(iter, trg, head, link) { |
0db9d74e | 591 | /* Skip irrelevant regions that start before our range. */ |
84448c8e | 592 | if (iter->from < f) { |
0db9d74e MA |
593 | /* If this region ends after the last accounted offset, |
594 | * then we need to update last_accounted_offset. | |
595 | */ | |
84448c8e JK |
596 | if (iter->to > last_accounted_offset) |
597 | last_accounted_offset = iter->to; | |
0db9d74e MA |
598 | continue; |
599 | } | |
d75c6af9 | 600 | |
0db9d74e MA |
601 | /* When we find a region that starts beyond our range, we've |
602 | * finished. | |
603 | */ | |
84448c8e JK |
604 | if (iter->from >= t) { |
605 | rg = iter->link.prev; | |
d75c6af9 | 606 | break; |
84448c8e | 607 | } |
d75c6af9 | 608 | |
84448c8e | 609 | /* Add an entry for last_accounted_offset -> iter->from, and |
0db9d74e MA |
610 | * update last_accounted_offset. |
611 | */ | |
84448c8e JK |
612 | if (iter->from > last_accounted_offset) |
613 | add += hugetlb_resv_map_add(resv, iter->link.prev, | |
2103cf9c | 614 | last_accounted_offset, |
84448c8e | 615 | iter->from, h, h_cg, |
2103cf9c | 616 | regions_needed); |
0db9d74e | 617 | |
84448c8e | 618 | last_accounted_offset = iter->to; |
0db9d74e MA |
619 | } |
620 | ||
621 | /* Handle the case where our range extends beyond | |
622 | * last_accounted_offset. | |
623 | */ | |
84448c8e JK |
624 | if (!rg) |
625 | rg = head->prev; | |
2103cf9c PX |
626 | if (last_accounted_offset < t) |
627 | add += hugetlb_resv_map_add(resv, rg, last_accounted_offset, | |
628 | t, h, h_cg, regions_needed); | |
0db9d74e | 629 | |
0db9d74e MA |
630 | return add; |
631 | } | |
632 | ||
633 | /* Must be called with resv->lock acquired. Will drop lock to allocate entries. | |
634 | */ | |
635 | static int allocate_file_region_entries(struct resv_map *resv, | |
636 | int regions_needed) | |
637 | __must_hold(&resv->lock) | |
638 | { | |
34665341 | 639 | LIST_HEAD(allocated_regions); |
0db9d74e MA |
640 | int to_allocate = 0, i = 0; |
641 | struct file_region *trg = NULL, *rg = NULL; | |
642 | ||
643 | VM_BUG_ON(regions_needed < 0); | |
644 | ||
0db9d74e MA |
645 | /* |
646 | * Check for sufficient descriptors in the cache to accommodate | |
647 | * the number of in progress add operations plus regions_needed. | |
648 | * | |
649 | * This is a while loop because when we drop the lock, some other call | |
650 | * to region_add or region_del may have consumed some region_entries, | |
651 | * so we keep looping here until we finally have enough entries for | |
652 | * (adds_in_progress + regions_needed). | |
653 | */ | |
654 | while (resv->region_cache_count < | |
655 | (resv->adds_in_progress + regions_needed)) { | |
656 | to_allocate = resv->adds_in_progress + regions_needed - | |
657 | resv->region_cache_count; | |
658 | ||
659 | /* At this point, we should have enough entries in the cache | |
f0953a1b | 660 | * for all the existing adds_in_progress. We should only be |
0db9d74e | 661 | * needing to allocate for regions_needed. |
d75c6af9 | 662 | */ |
0db9d74e MA |
663 | VM_BUG_ON(resv->region_cache_count < resv->adds_in_progress); |
664 | ||
665 | spin_unlock(&resv->lock); | |
666 | for (i = 0; i < to_allocate; i++) { | |
667 | trg = kmalloc(sizeof(*trg), GFP_KERNEL); | |
668 | if (!trg) | |
669 | goto out_of_memory; | |
670 | list_add(&trg->link, &allocated_regions); | |
d75c6af9 | 671 | } |
d75c6af9 | 672 | |
0db9d74e MA |
673 | spin_lock(&resv->lock); |
674 | ||
d3ec7b6e WY |
675 | list_splice(&allocated_regions, &resv->region_cache); |
676 | resv->region_cache_count += to_allocate; | |
d75c6af9 MA |
677 | } |
678 | ||
0db9d74e | 679 | return 0; |
d75c6af9 | 680 | |
0db9d74e MA |
681 | out_of_memory: |
682 | list_for_each_entry_safe(rg, trg, &allocated_regions, link) { | |
683 | list_del(&rg->link); | |
684 | kfree(rg); | |
685 | } | |
686 | return -ENOMEM; | |
d75c6af9 MA |
687 | } |
688 | ||
1dd308a7 MK |
689 | /* |
690 | * Add the huge page range represented by [f, t) to the reserve | |
0db9d74e MA |
691 | * map. Regions will be taken from the cache to fill in this range. |
692 | * Sufficient regions should exist in the cache due to the previous | |
693 | * call to region_chg with the same range, but in some cases the cache will not | |
694 | * have sufficient entries due to races with other code doing region_add or | |
695 | * region_del. The extra needed entries will be allocated. | |
cf3ad20b | 696 | * |
0db9d74e MA |
697 | * regions_needed is the out value provided by a previous call to region_chg. |
698 | * | |
699 | * Return the number of new huge pages added to the map. This number is greater | |
700 | * than or equal to zero. If file_region entries needed to be allocated for | |
7c8de358 | 701 | * this operation and we were not able to allocate, it returns -ENOMEM. |
0db9d74e MA |
702 | * region_add of regions of length 1 never allocate file_regions and cannot |
703 | * fail; region_chg will always allocate at least 1 entry and a region_add for | |
704 | * 1 page will only require at most 1 entry. | |
1dd308a7 | 705 | */ |
0db9d74e | 706 | static long region_add(struct resv_map *resv, long f, long t, |
075a61d0 MA |
707 | long in_regions_needed, struct hstate *h, |
708 | struct hugetlb_cgroup *h_cg) | |
96822904 | 709 | { |
0db9d74e | 710 | long add = 0, actual_regions_needed = 0; |
96822904 | 711 | |
7b24d861 | 712 | spin_lock(&resv->lock); |
0db9d74e MA |
713 | retry: |
714 | ||
715 | /* Count how many regions are actually needed to execute this add. */ | |
972a3da3 WY |
716 | add_reservation_in_range(resv, f, t, NULL, NULL, |
717 | &actual_regions_needed); | |
96822904 | 718 | |
5e911373 | 719 | /* |
0db9d74e MA |
720 | * Check for sufficient descriptors in the cache to accommodate |
721 | * this add operation. Note that actual_regions_needed may be greater | |
722 | * than in_regions_needed, as the resv_map may have been modified since | |
723 | * the region_chg call. In this case, we need to make sure that we | |
724 | * allocate extra entries, such that we have enough for all the | |
725 | * existing adds_in_progress, plus the excess needed for this | |
726 | * operation. | |
5e911373 | 727 | */ |
0db9d74e MA |
728 | if (actual_regions_needed > in_regions_needed && |
729 | resv->region_cache_count < | |
730 | resv->adds_in_progress + | |
731 | (actual_regions_needed - in_regions_needed)) { | |
732 | /* region_add operation of range 1 should never need to | |
733 | * allocate file_region entries. | |
734 | */ | |
735 | VM_BUG_ON(t - f <= 1); | |
5e911373 | 736 | |
0db9d74e MA |
737 | if (allocate_file_region_entries( |
738 | resv, actual_regions_needed - in_regions_needed)) { | |
739 | return -ENOMEM; | |
740 | } | |
5e911373 | 741 | |
0db9d74e | 742 | goto retry; |
5e911373 MK |
743 | } |
744 | ||
972a3da3 | 745 | add = add_reservation_in_range(resv, f, t, h_cg, h, NULL); |
0db9d74e MA |
746 | |
747 | resv->adds_in_progress -= in_regions_needed; | |
cf3ad20b | 748 | |
7b24d861 | 749 | spin_unlock(&resv->lock); |
cf3ad20b | 750 | return add; |
96822904 AW |
751 | } |
752 | ||
1dd308a7 MK |
753 | /* |
754 | * Examine the existing reserve map and determine how many | |
755 | * huge pages in the specified range [f, t) are NOT currently | |
756 | * represented. This routine is called before a subsequent | |
757 | * call to region_add that will actually modify the reserve | |
758 | * map to add the specified range [f, t). region_chg does | |
759 | * not change the number of huge pages represented by the | |
0db9d74e MA |
760 | * map. A number of new file_region structures is added to the cache as a |
761 | * placeholder, for the subsequent region_add call to use. At least 1 | |
762 | * file_region structure is added. | |
763 | * | |
764 | * out_regions_needed is the number of regions added to the | |
765 | * resv->adds_in_progress. This value needs to be provided to a follow up call | |
766 | * to region_add or region_abort for proper accounting. | |
5e911373 MK |
767 | * |
768 | * Returns the number of huge pages that need to be added to the existing | |
769 | * reservation map for the range [f, t). This number is greater or equal to | |
770 | * zero. -ENOMEM is returned if a new file_region structure or cache entry | |
771 | * is needed and can not be allocated. | |
1dd308a7 | 772 | */ |
0db9d74e MA |
773 | static long region_chg(struct resv_map *resv, long f, long t, |
774 | long *out_regions_needed) | |
96822904 | 775 | { |
96822904 AW |
776 | long chg = 0; |
777 | ||
7b24d861 | 778 | spin_lock(&resv->lock); |
5e911373 | 779 | |
972a3da3 | 780 | /* Count how many hugepages in this range are NOT represented. */ |
075a61d0 | 781 | chg = add_reservation_in_range(resv, f, t, NULL, NULL, |
972a3da3 | 782 | out_regions_needed); |
5e911373 | 783 | |
0db9d74e MA |
784 | if (*out_regions_needed == 0) |
785 | *out_regions_needed = 1; | |
5e911373 | 786 | |
0db9d74e MA |
787 | if (allocate_file_region_entries(resv, *out_regions_needed)) |
788 | return -ENOMEM; | |
5e911373 | 789 | |
0db9d74e | 790 | resv->adds_in_progress += *out_regions_needed; |
7b24d861 | 791 | |
7b24d861 | 792 | spin_unlock(&resv->lock); |
96822904 AW |
793 | return chg; |
794 | } | |
795 | ||
5e911373 MK |
796 | /* |
797 | * Abort the in progress add operation. The adds_in_progress field | |
798 | * of the resv_map keeps track of the operations in progress between | |
799 | * calls to region_chg and region_add. Operations are sometimes | |
800 | * aborted after the call to region_chg. In such cases, region_abort | |
0db9d74e MA |
801 | * is called to decrement the adds_in_progress counter. regions_needed |
802 | * is the value returned by the region_chg call, it is used to decrement | |
803 | * the adds_in_progress counter. | |
5e911373 MK |
804 | * |
805 | * NOTE: The range arguments [f, t) are not needed or used in this | |
806 | * routine. They are kept to make reading the calling code easier as | |
807 | * arguments will match the associated region_chg call. | |
808 | */ | |
0db9d74e MA |
809 | static void region_abort(struct resv_map *resv, long f, long t, |
810 | long regions_needed) | |
5e911373 MK |
811 | { |
812 | spin_lock(&resv->lock); | |
813 | VM_BUG_ON(!resv->region_cache_count); | |
0db9d74e | 814 | resv->adds_in_progress -= regions_needed; |
5e911373 MK |
815 | spin_unlock(&resv->lock); |
816 | } | |
817 | ||
1dd308a7 | 818 | /* |
feba16e2 MK |
819 | * Delete the specified range [f, t) from the reserve map. If the |
820 | * t parameter is LONG_MAX, this indicates that ALL regions after f | |
821 | * should be deleted. Locate the regions which intersect [f, t) | |
822 | * and either trim, delete or split the existing regions. | |
823 | * | |
824 | * Returns the number of huge pages deleted from the reserve map. | |
825 | * In the normal case, the return value is zero or more. In the | |
826 | * case where a region must be split, a new region descriptor must | |
827 | * be allocated. If the allocation fails, -ENOMEM will be returned. | |
828 | * NOTE: If the parameter t == LONG_MAX, then we will never split | |
829 | * a region and possibly return -ENOMEM. Callers specifying | |
830 | * t == LONG_MAX do not need to check for -ENOMEM error. | |
1dd308a7 | 831 | */ |
feba16e2 | 832 | static long region_del(struct resv_map *resv, long f, long t) |
96822904 | 833 | { |
1406ec9b | 834 | struct list_head *head = &resv->regions; |
96822904 | 835 | struct file_region *rg, *trg; |
feba16e2 MK |
836 | struct file_region *nrg = NULL; |
837 | long del = 0; | |
96822904 | 838 | |
feba16e2 | 839 | retry: |
7b24d861 | 840 | spin_lock(&resv->lock); |
feba16e2 | 841 | list_for_each_entry_safe(rg, trg, head, link) { |
dbe409e4 MK |
842 | /* |
843 | * Skip regions before the range to be deleted. file_region | |
844 | * ranges are normally of the form [from, to). However, there | |
845 | * may be a "placeholder" entry in the map which is of the form | |
846 | * (from, to) with from == to. Check for placeholder entries | |
847 | * at the beginning of the range to be deleted. | |
848 | */ | |
849 | if (rg->to <= f && (rg->to != rg->from || rg->to != f)) | |
feba16e2 | 850 | continue; |
dbe409e4 | 851 | |
feba16e2 | 852 | if (rg->from >= t) |
96822904 | 853 | break; |
96822904 | 854 | |
feba16e2 MK |
855 | if (f > rg->from && t < rg->to) { /* Must split region */ |
856 | /* | |
857 | * Check for an entry in the cache before dropping | |
858 | * lock and attempting allocation. | |
859 | */ | |
860 | if (!nrg && | |
861 | resv->region_cache_count > resv->adds_in_progress) { | |
862 | nrg = list_first_entry(&resv->region_cache, | |
863 | struct file_region, | |
864 | link); | |
865 | list_del(&nrg->link); | |
866 | resv->region_cache_count--; | |
867 | } | |
96822904 | 868 | |
feba16e2 MK |
869 | if (!nrg) { |
870 | spin_unlock(&resv->lock); | |
871 | nrg = kmalloc(sizeof(*nrg), GFP_KERNEL); | |
872 | if (!nrg) | |
873 | return -ENOMEM; | |
874 | goto retry; | |
875 | } | |
876 | ||
877 | del += t - f; | |
79aa925b | 878 | hugetlb_cgroup_uncharge_file_region( |
d85aecf2 | 879 | resv, rg, t - f, false); |
feba16e2 MK |
880 | |
881 | /* New entry for end of split region */ | |
882 | nrg->from = t; | |
883 | nrg->to = rg->to; | |
075a61d0 MA |
884 | |
885 | copy_hugetlb_cgroup_uncharge_info(nrg, rg); | |
886 | ||
feba16e2 MK |
887 | INIT_LIST_HEAD(&nrg->link); |
888 | ||
889 | /* Original entry is trimmed */ | |
890 | rg->to = f; | |
891 | ||
892 | list_add(&nrg->link, &rg->link); | |
893 | nrg = NULL; | |
96822904 | 894 | break; |
feba16e2 MK |
895 | } |
896 | ||
897 | if (f <= rg->from && t >= rg->to) { /* Remove entire region */ | |
898 | del += rg->to - rg->from; | |
075a61d0 | 899 | hugetlb_cgroup_uncharge_file_region(resv, rg, |
d85aecf2 | 900 | rg->to - rg->from, true); |
feba16e2 MK |
901 | list_del(&rg->link); |
902 | kfree(rg); | |
903 | continue; | |
904 | } | |
905 | ||
906 | if (f <= rg->from) { /* Trim beginning of region */ | |
075a61d0 | 907 | hugetlb_cgroup_uncharge_file_region(resv, rg, |
d85aecf2 | 908 | t - rg->from, false); |
075a61d0 | 909 | |
79aa925b MK |
910 | del += t - rg->from; |
911 | rg->from = t; | |
912 | } else { /* Trim end of region */ | |
075a61d0 | 913 | hugetlb_cgroup_uncharge_file_region(resv, rg, |
d85aecf2 | 914 | rg->to - f, false); |
79aa925b MK |
915 | |
916 | del += rg->to - f; | |
917 | rg->to = f; | |
feba16e2 | 918 | } |
96822904 | 919 | } |
7b24d861 | 920 | |
7b24d861 | 921 | spin_unlock(&resv->lock); |
feba16e2 MK |
922 | kfree(nrg); |
923 | return del; | |
96822904 AW |
924 | } |
925 | ||
b5cec28d MK |
926 | /* |
927 | * A rare out of memory error was encountered which prevented removal of | |
928 | * the reserve map region for a page. The huge page itself was free'ed | |
929 | * and removed from the page cache. This routine will adjust the subpool | |
930 | * usage count, and the global reserve count if needed. By incrementing | |
931 | * these counts, the reserve map entry which could not be deleted will | |
932 | * appear as a "reserved" entry instead of simply dangling with incorrect | |
933 | * counts. | |
934 | */ | |
72e2936c | 935 | void hugetlb_fix_reserve_counts(struct inode *inode) |
b5cec28d MK |
936 | { |
937 | struct hugepage_subpool *spool = subpool_inode(inode); | |
938 | long rsv_adjust; | |
da56388c | 939 | bool reserved = false; |
b5cec28d MK |
940 | |
941 | rsv_adjust = hugepage_subpool_get_pages(spool, 1); | |
da56388c | 942 | if (rsv_adjust > 0) { |
b5cec28d MK |
943 | struct hstate *h = hstate_inode(inode); |
944 | ||
da56388c ML |
945 | if (!hugetlb_acct_memory(h, 1)) |
946 | reserved = true; | |
947 | } else if (!rsv_adjust) { | |
948 | reserved = true; | |
b5cec28d | 949 | } |
da56388c ML |
950 | |
951 | if (!reserved) | |
952 | pr_warn("hugetlb: Huge Page Reserved count may go negative.\n"); | |
b5cec28d MK |
953 | } |
954 | ||
1dd308a7 MK |
955 | /* |
956 | * Count and return the number of huge pages in the reserve map | |
957 | * that intersect with the range [f, t). | |
958 | */ | |
1406ec9b | 959 | static long region_count(struct resv_map *resv, long f, long t) |
84afd99b | 960 | { |
1406ec9b | 961 | struct list_head *head = &resv->regions; |
84afd99b AW |
962 | struct file_region *rg; |
963 | long chg = 0; | |
964 | ||
7b24d861 | 965 | spin_lock(&resv->lock); |
84afd99b AW |
966 | /* Locate each segment we overlap with, and count that overlap. */ |
967 | list_for_each_entry(rg, head, link) { | |
f2135a4a WSH |
968 | long seg_from; |
969 | long seg_to; | |
84afd99b AW |
970 | |
971 | if (rg->to <= f) | |
972 | continue; | |
973 | if (rg->from >= t) | |
974 | break; | |
975 | ||
976 | seg_from = max(rg->from, f); | |
977 | seg_to = min(rg->to, t); | |
978 | ||
979 | chg += seg_to - seg_from; | |
980 | } | |
7b24d861 | 981 | spin_unlock(&resv->lock); |
84afd99b AW |
982 | |
983 | return chg; | |
984 | } | |
985 | ||
e7c4b0bf AW |
986 | /* |
987 | * Convert the address within this vma to the page offset within | |
a08c7193 | 988 | * the mapping, huge page units here. |
e7c4b0bf | 989 | */ |
a5516438 AK |
990 | static pgoff_t vma_hugecache_offset(struct hstate *h, |
991 | struct vm_area_struct *vma, unsigned long address) | |
e7c4b0bf | 992 | { |
a5516438 AK |
993 | return ((address - vma->vm_start) >> huge_page_shift(h)) + |
994 | (vma->vm_pgoff >> huge_page_order(h)); | |
e7c4b0bf AW |
995 | } |
996 | ||
8cfd014e MWO |
997 | /** |
998 | * vma_kernel_pagesize - Page size granularity for this VMA. | |
999 | * @vma: The user mapping. | |
1000 | * | |
1001 | * Folios in this VMA will be aligned to, and at least the size of the | |
1002 | * number of bytes returned by this function. | |
1003 | * | |
1004 | * Return: The default size of the folios allocated when backing a VMA. | |
08fba699 MG |
1005 | */ |
1006 | unsigned long vma_kernel_pagesize(struct vm_area_struct *vma) | |
1007 | { | |
05ea8860 DW |
1008 | if (vma->vm_ops && vma->vm_ops->pagesize) |
1009 | return vma->vm_ops->pagesize(vma); | |
1010 | return PAGE_SIZE; | |
08fba699 | 1011 | } |
f340ca0f | 1012 | EXPORT_SYMBOL_GPL(vma_kernel_pagesize); |
08fba699 | 1013 | |
3340289d MG |
1014 | /* |
1015 | * Return the page size being used by the MMU to back a VMA. In the majority | |
1016 | * of cases, the page size used by the kernel matches the MMU size. On | |
09135cc5 DW |
1017 | * architectures where it differs, an architecture-specific 'strong' |
1018 | * version of this symbol is required. | |
3340289d | 1019 | */ |
09135cc5 | 1020 | __weak unsigned long vma_mmu_pagesize(struct vm_area_struct *vma) |
3340289d MG |
1021 | { |
1022 | return vma_kernel_pagesize(vma); | |
1023 | } | |
3340289d | 1024 | |
84afd99b AW |
1025 | /* |
1026 | * Flags for MAP_PRIVATE reservations. These are stored in the bottom | |
1027 | * bits of the reservation map pointer, which are always clear due to | |
1028 | * alignment. | |
1029 | */ | |
1030 | #define HPAGE_RESV_OWNER (1UL << 0) | |
1031 | #define HPAGE_RESV_UNMAPPED (1UL << 1) | |
04f2cbe3 | 1032 | #define HPAGE_RESV_MASK (HPAGE_RESV_OWNER | HPAGE_RESV_UNMAPPED) |
84afd99b | 1033 | |
a1e78772 MG |
1034 | /* |
1035 | * These helpers are used to track how many pages are reserved for | |
1036 | * faults in a MAP_PRIVATE mapping. Only the process that called mmap() | |
1037 | * is guaranteed to have their future faults succeed. | |
1038 | * | |
8d9bfb26 | 1039 | * With the exception of hugetlb_dup_vma_private() which is called at fork(), |
a1e78772 MG |
1040 | * the reserve counters are updated with the hugetlb_lock held. It is safe |
1041 | * to reset the VMA at fork() time as it is not in use yet and there is no | |
1042 | * chance of the global counters getting corrupted as a result of the values. | |
84afd99b AW |
1043 | * |
1044 | * The private mapping reservation is represented in a subtly different | |
1045 | * manner to a shared mapping. A shared mapping has a region map associated | |
1046 | * with the underlying file, this region map represents the backing file | |
1047 | * pages which have ever had a reservation assigned which this persists even | |
1048 | * after the page is instantiated. A private mapping has a region map | |
1049 | * associated with the original mmap which is attached to all VMAs which | |
1050 | * reference it, this region map represents those offsets which have consumed | |
1051 | * reservation ie. where pages have been instantiated. | |
a1e78772 | 1052 | */ |
e7c4b0bf AW |
1053 | static unsigned long get_vma_private_data(struct vm_area_struct *vma) |
1054 | { | |
1055 | return (unsigned long)vma->vm_private_data; | |
1056 | } | |
1057 | ||
1058 | static void set_vma_private_data(struct vm_area_struct *vma, | |
1059 | unsigned long value) | |
1060 | { | |
1061 | vma->vm_private_data = (void *)value; | |
1062 | } | |
1063 | ||
e9fe92ae MA |
1064 | static void |
1065 | resv_map_set_hugetlb_cgroup_uncharge_info(struct resv_map *resv_map, | |
1066 | struct hugetlb_cgroup *h_cg, | |
1067 | struct hstate *h) | |
1068 | { | |
1069 | #ifdef CONFIG_CGROUP_HUGETLB | |
1070 | if (!h_cg || !h) { | |
1071 | resv_map->reservation_counter = NULL; | |
1072 | resv_map->pages_per_hpage = 0; | |
1073 | resv_map->css = NULL; | |
1074 | } else { | |
1075 | resv_map->reservation_counter = | |
1076 | &h_cg->rsvd_hugepage[hstate_index(h)]; | |
1077 | resv_map->pages_per_hpage = pages_per_huge_page(h); | |
1078 | resv_map->css = &h_cg->css; | |
1079 | } | |
1080 | #endif | |
1081 | } | |
1082 | ||
9119a41e | 1083 | struct resv_map *resv_map_alloc(void) |
84afd99b AW |
1084 | { |
1085 | struct resv_map *resv_map = kmalloc(sizeof(*resv_map), GFP_KERNEL); | |
5e911373 MK |
1086 | struct file_region *rg = kmalloc(sizeof(*rg), GFP_KERNEL); |
1087 | ||
1088 | if (!resv_map || !rg) { | |
1089 | kfree(resv_map); | |
1090 | kfree(rg); | |
84afd99b | 1091 | return NULL; |
5e911373 | 1092 | } |
84afd99b AW |
1093 | |
1094 | kref_init(&resv_map->refs); | |
7b24d861 | 1095 | spin_lock_init(&resv_map->lock); |
84afd99b | 1096 | INIT_LIST_HEAD(&resv_map->regions); |
bf491692 | 1097 | init_rwsem(&resv_map->rw_sema); |
84afd99b | 1098 | |
5e911373 | 1099 | resv_map->adds_in_progress = 0; |
e9fe92ae MA |
1100 | /* |
1101 | * Initialize these to 0. On shared mappings, 0's here indicate these | |
1102 | * fields don't do cgroup accounting. On private mappings, these will be | |
1103 | * re-initialized to the proper values, to indicate that hugetlb cgroup | |
1104 | * reservations are to be un-charged from here. | |
1105 | */ | |
1106 | resv_map_set_hugetlb_cgroup_uncharge_info(resv_map, NULL, NULL); | |
5e911373 MK |
1107 | |
1108 | INIT_LIST_HEAD(&resv_map->region_cache); | |
1109 | list_add(&rg->link, &resv_map->region_cache); | |
1110 | resv_map->region_cache_count = 1; | |
1111 | ||
84afd99b AW |
1112 | return resv_map; |
1113 | } | |
1114 | ||
9119a41e | 1115 | void resv_map_release(struct kref *ref) |
84afd99b AW |
1116 | { |
1117 | struct resv_map *resv_map = container_of(ref, struct resv_map, refs); | |
5e911373 MK |
1118 | struct list_head *head = &resv_map->region_cache; |
1119 | struct file_region *rg, *trg; | |
84afd99b AW |
1120 | |
1121 | /* Clear out any active regions before we release the map. */ | |
feba16e2 | 1122 | region_del(resv_map, 0, LONG_MAX); |
5e911373 MK |
1123 | |
1124 | /* ... and any entries left in the cache */ | |
1125 | list_for_each_entry_safe(rg, trg, head, link) { | |
1126 | list_del(&rg->link); | |
1127 | kfree(rg); | |
1128 | } | |
1129 | ||
1130 | VM_BUG_ON(resv_map->adds_in_progress); | |
1131 | ||
84afd99b AW |
1132 | kfree(resv_map); |
1133 | } | |
1134 | ||
4e35f483 JK |
1135 | static inline struct resv_map *inode_resv_map(struct inode *inode) |
1136 | { | |
f27a5136 MK |
1137 | /* |
1138 | * At inode evict time, i_mapping may not point to the original | |
1139 | * address space within the inode. This original address space | |
1140 | * contains the pointer to the resv_map. So, always use the | |
1141 | * address space embedded within the inode. | |
1142 | * The VERY common case is inode->mapping == &inode->i_data but, | |
1143 | * this may not be true for device special inodes. | |
1144 | */ | |
600f111e | 1145 | return (struct resv_map *)(&inode->i_data)->i_private_data; |
4e35f483 JK |
1146 | } |
1147 | ||
84afd99b | 1148 | static struct resv_map *vma_resv_map(struct vm_area_struct *vma) |
a1e78772 | 1149 | { |
81d1b09c | 1150 | VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); |
4e35f483 JK |
1151 | if (vma->vm_flags & VM_MAYSHARE) { |
1152 | struct address_space *mapping = vma->vm_file->f_mapping; | |
1153 | struct inode *inode = mapping->host; | |
1154 | ||
1155 | return inode_resv_map(inode); | |
1156 | ||
1157 | } else { | |
84afd99b AW |
1158 | return (struct resv_map *)(get_vma_private_data(vma) & |
1159 | ~HPAGE_RESV_MASK); | |
4e35f483 | 1160 | } |
a1e78772 MG |
1161 | } |
1162 | ||
84afd99b | 1163 | static void set_vma_resv_map(struct vm_area_struct *vma, struct resv_map *map) |
a1e78772 | 1164 | { |
81d1b09c SL |
1165 | VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); |
1166 | VM_BUG_ON_VMA(vma->vm_flags & VM_MAYSHARE, vma); | |
a1e78772 | 1167 | |
92fe9dcb | 1168 | set_vma_private_data(vma, (unsigned long)map); |
04f2cbe3 MG |
1169 | } |
1170 | ||
1171 | static void set_vma_resv_flags(struct vm_area_struct *vma, unsigned long flags) | |
1172 | { | |
81d1b09c SL |
1173 | VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); |
1174 | VM_BUG_ON_VMA(vma->vm_flags & VM_MAYSHARE, vma); | |
e7c4b0bf AW |
1175 | |
1176 | set_vma_private_data(vma, get_vma_private_data(vma) | flags); | |
04f2cbe3 MG |
1177 | } |
1178 | ||
1179 | static int is_vma_resv_set(struct vm_area_struct *vma, unsigned long flag) | |
1180 | { | |
81d1b09c | 1181 | VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); |
e7c4b0bf AW |
1182 | |
1183 | return (get_vma_private_data(vma) & flag) != 0; | |
a1e78772 MG |
1184 | } |
1185 | ||
187da0f8 MK |
1186 | bool __vma_private_lock(struct vm_area_struct *vma) |
1187 | { | |
1188 | return !(vma->vm_flags & VM_MAYSHARE) && | |
1189 | get_vma_private_data(vma) & ~HPAGE_RESV_MASK && | |
1190 | is_vma_resv_set(vma, HPAGE_RESV_OWNER); | |
1191 | } | |
1192 | ||
8d9bfb26 | 1193 | void hugetlb_dup_vma_private(struct vm_area_struct *vma) |
a1e78772 | 1194 | { |
81d1b09c | 1195 | VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); |
8d9bfb26 MK |
1196 | /* |
1197 | * Clear vm_private_data | |
612b8a31 MK |
1198 | * - For shared mappings this is a per-vma semaphore that may be |
1199 | * allocated in a subsequent call to hugetlb_vm_op_open. | |
1200 | * Before clearing, make sure pointer is not associated with vma | |
1201 | * as this will leak the structure. This is the case when called | |
1202 | * via clear_vma_resv_huge_pages() and hugetlb_vm_op_open has already | |
1203 | * been called to allocate a new structure. | |
8d9bfb26 MK |
1204 | * - For MAP_PRIVATE mappings, this is the reserve map which does |
1205 | * not apply to children. Faults generated by the children are | |
1206 | * not guaranteed to succeed, even if read-only. | |
8d9bfb26 | 1207 | */ |
612b8a31 MK |
1208 | if (vma->vm_flags & VM_MAYSHARE) { |
1209 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
1210 | ||
1211 | if (vma_lock && vma_lock->vma != vma) | |
1212 | vma->vm_private_data = NULL; | |
1213 | } else | |
1214 | vma->vm_private_data = NULL; | |
a1e78772 MG |
1215 | } |
1216 | ||
550a7d60 MA |
1217 | /* |
1218 | * Reset and decrement one ref on hugepage private reservation. | |
8651a137 | 1219 | * Called with mm->mmap_lock writer semaphore held. |
550a7d60 MA |
1220 | * This function should be only used by move_vma() and operate on |
1221 | * same sized vma. It should never come here with last ref on the | |
1222 | * reservation. | |
1223 | */ | |
1224 | void clear_vma_resv_huge_pages(struct vm_area_struct *vma) | |
1225 | { | |
1226 | /* | |
1227 | * Clear the old hugetlb private page reservation. | |
1228 | * It has already been transferred to new_vma. | |
1229 | * | |
1230 | * During a mremap() operation of a hugetlb vma we call move_vma() | |
1231 | * which copies vma into new_vma and unmaps vma. After the copy | |
1232 | * operation both new_vma and vma share a reference to the resv_map | |
1233 | * struct, and at that point vma is about to be unmapped. We don't | |
1234 | * want to return the reservation to the pool at unmap of vma because | |
1235 | * the reservation still lives on in new_vma, so simply decrement the | |
1236 | * ref here and remove the resv_map reference from this vma. | |
1237 | */ | |
1238 | struct resv_map *reservations = vma_resv_map(vma); | |
1239 | ||
afe041c2 BQM |
1240 | if (reservations && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { |
1241 | resv_map_put_hugetlb_cgroup_uncharge_info(reservations); | |
550a7d60 | 1242 | kref_put(&reservations->refs, resv_map_release); |
afe041c2 | 1243 | } |
550a7d60 | 1244 | |
8d9bfb26 | 1245 | hugetlb_dup_vma_private(vma); |
550a7d60 MA |
1246 | } |
1247 | ||
a1e78772 | 1248 | /* Returns true if the VMA has associated reserve pages */ |
559ec2f8 | 1249 | static bool vma_has_reserves(struct vm_area_struct *vma, long chg) |
a1e78772 | 1250 | { |
af0ed73e JK |
1251 | if (vma->vm_flags & VM_NORESERVE) { |
1252 | /* | |
1253 | * This address is already reserved by other process(chg == 0), | |
1254 | * so, we should decrement reserved count. Without decrementing, | |
1255 | * reserve count remains after releasing inode, because this | |
1256 | * allocated page will go into page cache and is regarded as | |
1257 | * coming from reserved pool in releasing step. Currently, we | |
1258 | * don't have any other solution to deal with this situation | |
1259 | * properly, so add work-around here. | |
1260 | */ | |
1261 | if (vma->vm_flags & VM_MAYSHARE && chg == 0) | |
559ec2f8 | 1262 | return true; |
af0ed73e | 1263 | else |
559ec2f8 | 1264 | return false; |
af0ed73e | 1265 | } |
a63884e9 JK |
1266 | |
1267 | /* Shared mappings always use reserves */ | |
1fb1b0e9 MK |
1268 | if (vma->vm_flags & VM_MAYSHARE) { |
1269 | /* | |
1270 | * We know VM_NORESERVE is not set. Therefore, there SHOULD | |
1271 | * be a region map for all pages. The only situation where | |
1272 | * there is no region map is if a hole was punched via | |
7c8de358 | 1273 | * fallocate. In this case, there really are no reserves to |
1fb1b0e9 MK |
1274 | * use. This situation is indicated if chg != 0. |
1275 | */ | |
1276 | if (chg) | |
1277 | return false; | |
1278 | else | |
1279 | return true; | |
1280 | } | |
a63884e9 JK |
1281 | |
1282 | /* | |
1283 | * Only the process that called mmap() has reserves for | |
1284 | * private mappings. | |
1285 | */ | |
67961f9d MK |
1286 | if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { |
1287 | /* | |
1288 | * Like the shared case above, a hole punch or truncate | |
1289 | * could have been performed on the private mapping. | |
1290 | * Examine the value of chg to determine if reserves | |
1291 | * actually exist or were previously consumed. | |
1292 | * Very Subtle - The value of chg comes from a previous | |
1293 | * call to vma_needs_reserves(). The reserve map for | |
1294 | * private mappings has different (opposite) semantics | |
1295 | * than that of shared mappings. vma_needs_reserves() | |
1296 | * has already taken this difference in semantics into | |
1297 | * account. Therefore, the meaning of chg is the same | |
1298 | * as in the shared case above. Code could easily be | |
1299 | * combined, but keeping it separate draws attention to | |
1300 | * subtle differences. | |
1301 | */ | |
1302 | if (chg) | |
1303 | return false; | |
1304 | else | |
1305 | return true; | |
1306 | } | |
a63884e9 | 1307 | |
559ec2f8 | 1308 | return false; |
a1e78772 MG |
1309 | } |
1310 | ||
240d67a8 | 1311 | static void enqueue_hugetlb_folio(struct hstate *h, struct folio *folio) |
1da177e4 | 1312 | { |
240d67a8 | 1313 | int nid = folio_nid(folio); |
9487ca60 MK |
1314 | |
1315 | lockdep_assert_held(&hugetlb_lock); | |
240d67a8 | 1316 | VM_BUG_ON_FOLIO(folio_ref_count(folio), folio); |
b65a4eda | 1317 | |
240d67a8 | 1318 | list_move(&folio->lru, &h->hugepage_freelists[nid]); |
a5516438 AK |
1319 | h->free_huge_pages++; |
1320 | h->free_huge_pages_node[nid]++; | |
240d67a8 | 1321 | folio_set_hugetlb_freed(folio); |
1da177e4 LT |
1322 | } |
1323 | ||
a36f1e90 SK |
1324 | static struct folio *dequeue_hugetlb_folio_node_exact(struct hstate *h, |
1325 | int nid) | |
bf50bab2 | 1326 | { |
a36f1e90 | 1327 | struct folio *folio; |
1a08ae36 | 1328 | bool pin = !!(current->flags & PF_MEMALLOC_PIN); |
bbe88753 | 1329 | |
9487ca60 | 1330 | lockdep_assert_held(&hugetlb_lock); |
a36f1e90 SK |
1331 | list_for_each_entry(folio, &h->hugepage_freelists[nid], lru) { |
1332 | if (pin && !folio_is_longterm_pinnable(folio)) | |
bbe88753 | 1333 | continue; |
bf50bab2 | 1334 | |
a36f1e90 | 1335 | if (folio_test_hwpoison(folio)) |
6664bfc8 WY |
1336 | continue; |
1337 | ||
a36f1e90 SK |
1338 | list_move(&folio->lru, &h->hugepage_activelist); |
1339 | folio_ref_unfreeze(folio, 1); | |
1340 | folio_clear_hugetlb_freed(folio); | |
6664bfc8 WY |
1341 | h->free_huge_pages--; |
1342 | h->free_huge_pages_node[nid]--; | |
a36f1e90 | 1343 | return folio; |
bbe88753 JK |
1344 | } |
1345 | ||
6664bfc8 | 1346 | return NULL; |
bf50bab2 NH |
1347 | } |
1348 | ||
a36f1e90 SK |
1349 | static struct folio *dequeue_hugetlb_folio_nodemask(struct hstate *h, gfp_t gfp_mask, |
1350 | int nid, nodemask_t *nmask) | |
94310cbc | 1351 | { |
3e59fcb0 MH |
1352 | unsigned int cpuset_mems_cookie; |
1353 | struct zonelist *zonelist; | |
1354 | struct zone *zone; | |
1355 | struct zoneref *z; | |
98fa15f3 | 1356 | int node = NUMA_NO_NODE; |
94310cbc | 1357 | |
3e59fcb0 MH |
1358 | zonelist = node_zonelist(nid, gfp_mask); |
1359 | ||
1360 | retry_cpuset: | |
1361 | cpuset_mems_cookie = read_mems_allowed_begin(); | |
1362 | for_each_zone_zonelist_nodemask(zone, z, zonelist, gfp_zone(gfp_mask), nmask) { | |
a36f1e90 | 1363 | struct folio *folio; |
3e59fcb0 MH |
1364 | |
1365 | if (!cpuset_zone_allowed(zone, gfp_mask)) | |
1366 | continue; | |
1367 | /* | |
1368 | * no need to ask again on the same node. Pool is node rather than | |
1369 | * zone aware | |
1370 | */ | |
1371 | if (zone_to_nid(zone) == node) | |
1372 | continue; | |
1373 | node = zone_to_nid(zone); | |
94310cbc | 1374 | |
a36f1e90 SK |
1375 | folio = dequeue_hugetlb_folio_node_exact(h, node); |
1376 | if (folio) | |
1377 | return folio; | |
94310cbc | 1378 | } |
3e59fcb0 MH |
1379 | if (unlikely(read_mems_allowed_retry(cpuset_mems_cookie))) |
1380 | goto retry_cpuset; | |
1381 | ||
94310cbc AK |
1382 | return NULL; |
1383 | } | |
1384 | ||
8346d69d XH |
1385 | static unsigned long available_huge_pages(struct hstate *h) |
1386 | { | |
1387 | return h->free_huge_pages - h->resv_huge_pages; | |
1388 | } | |
1389 | ||
ff7d853b | 1390 | static struct folio *dequeue_hugetlb_folio_vma(struct hstate *h, |
a5516438 | 1391 | struct vm_area_struct *vma, |
af0ed73e JK |
1392 | unsigned long address, int avoid_reserve, |
1393 | long chg) | |
1da177e4 | 1394 | { |
a36f1e90 | 1395 | struct folio *folio = NULL; |
480eccf9 | 1396 | struct mempolicy *mpol; |
04ec6264 | 1397 | gfp_t gfp_mask; |
3e59fcb0 | 1398 | nodemask_t *nodemask; |
04ec6264 | 1399 | int nid; |
1da177e4 | 1400 | |
a1e78772 MG |
1401 | /* |
1402 | * A child process with MAP_PRIVATE mappings created by their parent | |
1403 | * have no page reserves. This check ensures that reservations are | |
1404 | * not "stolen". The child may still get SIGKILLed | |
1405 | */ | |
8346d69d | 1406 | if (!vma_has_reserves(vma, chg) && !available_huge_pages(h)) |
c0ff7453 | 1407 | goto err; |
a1e78772 | 1408 | |
04f2cbe3 | 1409 | /* If reserves cannot be used, ensure enough pages are in the pool */ |
8346d69d | 1410 | if (avoid_reserve && !available_huge_pages(h)) |
6eab04a8 | 1411 | goto err; |
04f2cbe3 | 1412 | |
04ec6264 VB |
1413 | gfp_mask = htlb_alloc_mask(h); |
1414 | nid = huge_node(vma, address, gfp_mask, &mpol, &nodemask); | |
cfcaa66f BW |
1415 | |
1416 | if (mpol_is_preferred_many(mpol)) { | |
a36f1e90 SK |
1417 | folio = dequeue_hugetlb_folio_nodemask(h, gfp_mask, |
1418 | nid, nodemask); | |
cfcaa66f BW |
1419 | |
1420 | /* Fallback to all nodes if page==NULL */ | |
1421 | nodemask = NULL; | |
1422 | } | |
1423 | ||
a36f1e90 SK |
1424 | if (!folio) |
1425 | folio = dequeue_hugetlb_folio_nodemask(h, gfp_mask, | |
1426 | nid, nodemask); | |
cfcaa66f | 1427 | |
a36f1e90 SK |
1428 | if (folio && !avoid_reserve && vma_has_reserves(vma, chg)) { |
1429 | folio_set_hugetlb_restore_reserve(folio); | |
3e59fcb0 | 1430 | h->resv_huge_pages--; |
1da177e4 | 1431 | } |
cc9a6c87 | 1432 | |
52cd3b07 | 1433 | mpol_cond_put(mpol); |
ff7d853b | 1434 | return folio; |
cc9a6c87 MG |
1435 | |
1436 | err: | |
cc9a6c87 | 1437 | return NULL; |
1da177e4 LT |
1438 | } |
1439 | ||
1cac6f2c LC |
1440 | /* |
1441 | * common helper functions for hstate_next_node_to_{alloc|free}. | |
1442 | * We may have allocated or freed a huge page based on a different | |
1443 | * nodes_allowed previously, so h->next_node_to_{alloc|free} might | |
1444 | * be outside of *nodes_allowed. Ensure that we use an allowed | |
1445 | * node for alloc or free. | |
1446 | */ | |
1447 | static int next_node_allowed(int nid, nodemask_t *nodes_allowed) | |
1448 | { | |
0edaf86c | 1449 | nid = next_node_in(nid, *nodes_allowed); |
1cac6f2c LC |
1450 | VM_BUG_ON(nid >= MAX_NUMNODES); |
1451 | ||
1452 | return nid; | |
1453 | } | |
1454 | ||
1455 | static int get_valid_node_allowed(int nid, nodemask_t *nodes_allowed) | |
1456 | { | |
1457 | if (!node_isset(nid, *nodes_allowed)) | |
1458 | nid = next_node_allowed(nid, nodes_allowed); | |
1459 | return nid; | |
1460 | } | |
1461 | ||
1462 | /* | |
1463 | * returns the previously saved node ["this node"] from which to | |
1464 | * allocate a persistent huge page for the pool and advance the | |
1465 | * next node from which to allocate, handling wrap at end of node | |
1466 | * mask. | |
1467 | */ | |
2e73ff23 | 1468 | static int hstate_next_node_to_alloc(int *next_node, |
1cac6f2c LC |
1469 | nodemask_t *nodes_allowed) |
1470 | { | |
1471 | int nid; | |
1472 | ||
1473 | VM_BUG_ON(!nodes_allowed); | |
1474 | ||
2e73ff23 GL |
1475 | nid = get_valid_node_allowed(*next_node, nodes_allowed); |
1476 | *next_node = next_node_allowed(nid, nodes_allowed); | |
1cac6f2c LC |
1477 | |
1478 | return nid; | |
1479 | } | |
1480 | ||
1481 | /* | |
d5b43e96 | 1482 | * helper for remove_pool_hugetlb_folio() - return the previously saved |
1cac6f2c LC |
1483 | * node ["this node"] from which to free a huge page. Advance the |
1484 | * next node id whether or not we find a free huge page to free so | |
1485 | * that the next attempt to free addresses the next node. | |
1486 | */ | |
1487 | static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed) | |
1488 | { | |
1489 | int nid; | |
1490 | ||
1491 | VM_BUG_ON(!nodes_allowed); | |
1492 | ||
1493 | nid = get_valid_node_allowed(h->next_nid_to_free, nodes_allowed); | |
1494 | h->next_nid_to_free = next_node_allowed(nid, nodes_allowed); | |
1495 | ||
1496 | return nid; | |
1497 | } | |
1498 | ||
2e73ff23 | 1499 | #define for_each_node_mask_to_alloc(next_node, nr_nodes, node, mask) \ |
1cac6f2c LC |
1500 | for (nr_nodes = nodes_weight(*mask); \ |
1501 | nr_nodes > 0 && \ | |
2e73ff23 | 1502 | ((node = hstate_next_node_to_alloc(next_node, mask)) || 1); \ |
1cac6f2c LC |
1503 | nr_nodes--) |
1504 | ||
1505 | #define for_each_node_mask_to_free(hs, nr_nodes, node, mask) \ | |
1506 | for (nr_nodes = nodes_weight(*mask); \ | |
1507 | nr_nodes > 0 && \ | |
1508 | ((node = hstate_next_node_to_free(hs, mask)) || 1); \ | |
1509 | nr_nodes--) | |
1510 | ||
8531fc6f | 1511 | /* used to demote non-gigantic_huge pages as well */ |
911565b8 | 1512 | static void __destroy_compound_gigantic_folio(struct folio *folio, |
34d9e35b | 1513 | unsigned int order, bool demote) |
944d9fec LC |
1514 | { |
1515 | int i; | |
1516 | int nr_pages = 1 << order; | |
14455eab | 1517 | struct page *p; |
944d9fec | 1518 | |
46f27228 | 1519 | atomic_set(&folio->_entire_mapcount, 0); |
eec20426 | 1520 | atomic_set(&folio->_nr_pages_mapped, 0); |
94688e8e | 1521 | atomic_set(&folio->_pincount, 0); |
47e29d32 | 1522 | |
14455eab | 1523 | for (i = 1; i < nr_pages; i++) { |
911565b8 | 1524 | p = folio_page(folio, i); |
6c141973 | 1525 | p->flags &= ~PAGE_FLAGS_CHECK_AT_FREE; |
a01f4390 | 1526 | p->mapping = NULL; |
1d798ca3 | 1527 | clear_compound_head(p); |
34d9e35b MK |
1528 | if (!demote) |
1529 | set_page_refcounted(p); | |
944d9fec LC |
1530 | } |
1531 | ||
911565b8 | 1532 | __folio_clear_head(folio); |
944d9fec LC |
1533 | } |
1534 | ||
911565b8 | 1535 | static void destroy_compound_hugetlb_folio_for_demote(struct folio *folio, |
8531fc6f MK |
1536 | unsigned int order) |
1537 | { | |
911565b8 | 1538 | __destroy_compound_gigantic_folio(folio, order, true); |
8531fc6f MK |
1539 | } |
1540 | ||
1541 | #ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE | |
911565b8 | 1542 | static void destroy_compound_gigantic_folio(struct folio *folio, |
34d9e35b MK |
1543 | unsigned int order) |
1544 | { | |
911565b8 | 1545 | __destroy_compound_gigantic_folio(folio, order, false); |
34d9e35b MK |
1546 | } |
1547 | ||
7f325a8d | 1548 | static void free_gigantic_folio(struct folio *folio, unsigned int order) |
944d9fec | 1549 | { |
cf11e85f RG |
1550 | /* |
1551 | * If the page isn't allocated using the cma allocator, | |
1552 | * cma_release() returns false. | |
1553 | */ | |
dbda8fea | 1554 | #ifdef CONFIG_CMA |
7f325a8d SK |
1555 | int nid = folio_nid(folio); |
1556 | ||
1557 | if (cma_release(hugetlb_cma[nid], &folio->page, 1 << order)) | |
cf11e85f | 1558 | return; |
dbda8fea | 1559 | #endif |
cf11e85f | 1560 | |
7f325a8d | 1561 | free_contig_range(folio_pfn(folio), 1 << order); |
944d9fec LC |
1562 | } |
1563 | ||
4eb0716e | 1564 | #ifdef CONFIG_CONTIG_ALLOC |
19fc1a7e | 1565 | static struct folio *alloc_gigantic_folio(struct hstate *h, gfp_t gfp_mask, |
d9cc948f | 1566 | int nid, nodemask_t *nodemask) |
944d9fec | 1567 | { |
19fc1a7e | 1568 | struct page *page; |
04adbc3f | 1569 | unsigned long nr_pages = pages_per_huge_page(h); |
953f064a LX |
1570 | if (nid == NUMA_NO_NODE) |
1571 | nid = numa_mem_id(); | |
944d9fec | 1572 | |
dbda8fea BS |
1573 | #ifdef CONFIG_CMA |
1574 | { | |
cf11e85f RG |
1575 | int node; |
1576 | ||
953f064a LX |
1577 | if (hugetlb_cma[nid]) { |
1578 | page = cma_alloc(hugetlb_cma[nid], nr_pages, | |
1579 | huge_page_order(h), true); | |
cf11e85f | 1580 | if (page) |
19fc1a7e | 1581 | return page_folio(page); |
cf11e85f | 1582 | } |
953f064a LX |
1583 | |
1584 | if (!(gfp_mask & __GFP_THISNODE)) { | |
1585 | for_each_node_mask(node, *nodemask) { | |
1586 | if (node == nid || !hugetlb_cma[node]) | |
1587 | continue; | |
1588 | ||
1589 | page = cma_alloc(hugetlb_cma[node], nr_pages, | |
1590 | huge_page_order(h), true); | |
1591 | if (page) | |
19fc1a7e | 1592 | return page_folio(page); |
953f064a LX |
1593 | } |
1594 | } | |
cf11e85f | 1595 | } |
dbda8fea | 1596 | #endif |
cf11e85f | 1597 | |
19fc1a7e SK |
1598 | page = alloc_contig_pages(nr_pages, gfp_mask, nid, nodemask); |
1599 | return page ? page_folio(page) : NULL; | |
944d9fec LC |
1600 | } |
1601 | ||
4eb0716e | 1602 | #else /* !CONFIG_CONTIG_ALLOC */ |
19fc1a7e | 1603 | static struct folio *alloc_gigantic_folio(struct hstate *h, gfp_t gfp_mask, |
4eb0716e AG |
1604 | int nid, nodemask_t *nodemask) |
1605 | { | |
1606 | return NULL; | |
1607 | } | |
1608 | #endif /* CONFIG_CONTIG_ALLOC */ | |
944d9fec | 1609 | |
e1073d1e | 1610 | #else /* !CONFIG_ARCH_HAS_GIGANTIC_PAGE */ |
19fc1a7e | 1611 | static struct folio *alloc_gigantic_folio(struct hstate *h, gfp_t gfp_mask, |
4eb0716e AG |
1612 | int nid, nodemask_t *nodemask) |
1613 | { | |
1614 | return NULL; | |
1615 | } | |
7f325a8d SK |
1616 | static inline void free_gigantic_folio(struct folio *folio, |
1617 | unsigned int order) { } | |
911565b8 | 1618 | static inline void destroy_compound_gigantic_folio(struct folio *folio, |
d00181b9 | 1619 | unsigned int order) { } |
944d9fec LC |
1620 | #endif |
1621 | ||
32c87719 MK |
1622 | static inline void __clear_hugetlb_destructor(struct hstate *h, |
1623 | struct folio *folio) | |
1624 | { | |
1625 | lockdep_assert_held(&hugetlb_lock); | |
1626 | ||
9c5ccf2d | 1627 | folio_clear_hugetlb(folio); |
32c87719 MK |
1628 | } |
1629 | ||
6eb4e88a | 1630 | /* |
32c87719 MK |
1631 | * Remove hugetlb folio from lists. |
1632 | * If vmemmap exists for the folio, update dtor so that the folio appears | |
1633 | * as just a compound page. Otherwise, wait until after allocating vmemmap | |
1634 | * to update dtor. | |
34d9e35b | 1635 | * |
cfd5082b | 1636 | * A reference is held on the folio, except in the case of demote. |
6eb4e88a MK |
1637 | * |
1638 | * Must be called with hugetlb lock held. | |
1639 | */ | |
cfd5082b | 1640 | static void __remove_hugetlb_folio(struct hstate *h, struct folio *folio, |
34d9e35b MK |
1641 | bool adjust_surplus, |
1642 | bool demote) | |
6eb4e88a | 1643 | { |
cfd5082b | 1644 | int nid = folio_nid(folio); |
6eb4e88a | 1645 | |
f074732d SK |
1646 | VM_BUG_ON_FOLIO(hugetlb_cgroup_from_folio(folio), folio); |
1647 | VM_BUG_ON_FOLIO(hugetlb_cgroup_from_folio_rsvd(folio), folio); | |
6eb4e88a | 1648 | |
9487ca60 | 1649 | lockdep_assert_held(&hugetlb_lock); |
6eb4e88a MK |
1650 | if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) |
1651 | return; | |
1652 | ||
cfd5082b | 1653 | list_del(&folio->lru); |
6eb4e88a | 1654 | |
cfd5082b | 1655 | if (folio_test_hugetlb_freed(folio)) { |
6eb4e88a MK |
1656 | h->free_huge_pages--; |
1657 | h->free_huge_pages_node[nid]--; | |
1658 | } | |
1659 | if (adjust_surplus) { | |
1660 | h->surplus_huge_pages--; | |
1661 | h->surplus_huge_pages_node[nid]--; | |
1662 | } | |
1663 | ||
e32d20c0 | 1664 | /* |
32c87719 MK |
1665 | * We can only clear the hugetlb destructor after allocating vmemmap |
1666 | * pages. Otherwise, someone (memory error handling) may try to write | |
1667 | * to tail struct pages. | |
1668 | */ | |
1669 | if (!folio_test_hugetlb_vmemmap_optimized(folio)) | |
1670 | __clear_hugetlb_destructor(h, folio); | |
1671 | ||
1672 | /* | |
1673 | * In the case of demote we do not ref count the page as it will soon | |
1674 | * be turned into a page of smaller size. | |
e32d20c0 | 1675 | */ |
34d9e35b | 1676 | if (!demote) |
cfd5082b | 1677 | folio_ref_unfreeze(folio, 1); |
6eb4e88a MK |
1678 | |
1679 | h->nr_huge_pages--; | |
1680 | h->nr_huge_pages_node[nid]--; | |
1681 | } | |
1682 | ||
cfd5082b | 1683 | static void remove_hugetlb_folio(struct hstate *h, struct folio *folio, |
34d9e35b MK |
1684 | bool adjust_surplus) |
1685 | { | |
cfd5082b | 1686 | __remove_hugetlb_folio(h, folio, adjust_surplus, false); |
34d9e35b MK |
1687 | } |
1688 | ||
cfd5082b | 1689 | static void remove_hugetlb_folio_for_demote(struct hstate *h, struct folio *folio, |
8531fc6f MK |
1690 | bool adjust_surplus) |
1691 | { | |
cfd5082b | 1692 | __remove_hugetlb_folio(h, folio, adjust_surplus, true); |
8531fc6f MK |
1693 | } |
1694 | ||
2f6c57d6 | 1695 | static void add_hugetlb_folio(struct hstate *h, struct folio *folio, |
ad2fa371 MS |
1696 | bool adjust_surplus) |
1697 | { | |
1698 | int zeroed; | |
2f6c57d6 | 1699 | int nid = folio_nid(folio); |
ad2fa371 | 1700 | |
2f6c57d6 | 1701 | VM_BUG_ON_FOLIO(!folio_test_hugetlb_vmemmap_optimized(folio), folio); |
ad2fa371 MS |
1702 | |
1703 | lockdep_assert_held(&hugetlb_lock); | |
1704 | ||
2f6c57d6 | 1705 | INIT_LIST_HEAD(&folio->lru); |
ad2fa371 MS |
1706 | h->nr_huge_pages++; |
1707 | h->nr_huge_pages_node[nid]++; | |
1708 | ||
1709 | if (adjust_surplus) { | |
1710 | h->surplus_huge_pages++; | |
1711 | h->surplus_huge_pages_node[nid]++; | |
1712 | } | |
1713 | ||
9c5ccf2d | 1714 | folio_set_hugetlb(folio); |
2f6c57d6 | 1715 | folio_change_private(folio, NULL); |
a9e1eab2 | 1716 | /* |
2f6c57d6 SK |
1717 | * We have to set hugetlb_vmemmap_optimized again as above |
1718 | * folio_change_private(folio, NULL) cleared it. | |
a9e1eab2 | 1719 | */ |
2f6c57d6 | 1720 | folio_set_hugetlb_vmemmap_optimized(folio); |
ad2fa371 MS |
1721 | |
1722 | /* | |
2f6c57d6 | 1723 | * This folio is about to be managed by the hugetlb allocator and |
b65a4eda MK |
1724 | * should have no users. Drop our reference, and check for others |
1725 | * just in case. | |
ad2fa371 | 1726 | */ |
2f6c57d6 SK |
1727 | zeroed = folio_put_testzero(folio); |
1728 | if (unlikely(!zeroed)) | |
b65a4eda | 1729 | /* |
454a00c4 MWO |
1730 | * It is VERY unlikely soneone else has taken a ref |
1731 | * on the folio. In this case, we simply return as | |
1732 | * free_huge_folio() will be called when this other ref | |
1733 | * is dropped. | |
b65a4eda MK |
1734 | */ |
1735 | return; | |
1736 | ||
2f6c57d6 | 1737 | arch_clear_hugepage_flags(&folio->page); |
240d67a8 | 1738 | enqueue_hugetlb_folio(h, folio); |
ad2fa371 MS |
1739 | } |
1740 | ||
6f6956cf SK |
1741 | static void __update_and_free_hugetlb_folio(struct hstate *h, |
1742 | struct folio *folio) | |
6af2acb6 | 1743 | { |
32c87719 | 1744 | bool clear_dtor = folio_test_hugetlb_vmemmap_optimized(folio); |
a5516438 | 1745 | |
4eb0716e | 1746 | if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) |
944d9fec | 1747 | return; |
18229df5 | 1748 | |
161df60e NH |
1749 | /* |
1750 | * If we don't know which subpages are hwpoisoned, we can't free | |
1751 | * the hugepage, so it's leaked intentionally. | |
1752 | */ | |
7f325a8d | 1753 | if (folio_test_hugetlb_raw_hwp_unreliable(folio)) |
161df60e NH |
1754 | return; |
1755 | ||
d8f5f7e4 MK |
1756 | /* |
1757 | * If folio is not vmemmap optimized (!clear_dtor), then the folio | |
c5ad3233 | 1758 | * is no longer identified as a hugetlb page. hugetlb_vmemmap_restore_folio |
d8f5f7e4 MK |
1759 | * can only be passed hugetlb pages and will BUG otherwise. |
1760 | */ | |
c5ad3233 | 1761 | if (clear_dtor && hugetlb_vmemmap_restore_folio(h, folio)) { |
ad2fa371 MS |
1762 | spin_lock_irq(&hugetlb_lock); |
1763 | /* | |
1764 | * If we cannot allocate vmemmap pages, just refuse to free the | |
1765 | * page and put the page back on the hugetlb free list and treat | |
1766 | * as a surplus page. | |
1767 | */ | |
7f325a8d | 1768 | add_hugetlb_folio(h, folio, true); |
ad2fa371 MS |
1769 | spin_unlock_irq(&hugetlb_lock); |
1770 | return; | |
1771 | } | |
1772 | ||
161df60e NH |
1773 | /* |
1774 | * Move PageHWPoison flag from head page to the raw error pages, | |
1775 | * which makes any healthy subpages reusable. | |
1776 | */ | |
911565b8 | 1777 | if (unlikely(folio_test_hwpoison(folio))) |
2ff6cece | 1778 | folio_clear_hugetlb_hwpoison(folio); |
161df60e | 1779 | |
32c87719 MK |
1780 | /* |
1781 | * If vmemmap pages were allocated above, then we need to clear the | |
1782 | * hugetlb destructor under the hugetlb lock. | |
1783 | */ | |
1784 | if (clear_dtor) { | |
1785 | spin_lock_irq(&hugetlb_lock); | |
1786 | __clear_hugetlb_destructor(h, folio); | |
1787 | spin_unlock_irq(&hugetlb_lock); | |
1788 | } | |
1789 | ||
a01f4390 MK |
1790 | /* |
1791 | * Non-gigantic pages demoted from CMA allocated gigantic pages | |
7f325a8d | 1792 | * need to be given back to CMA in free_gigantic_folio. |
a01f4390 MK |
1793 | */ |
1794 | if (hstate_is_gigantic(h) || | |
2f6c57d6 | 1795 | hugetlb_cma_folio(folio, huge_page_order(h))) { |
911565b8 | 1796 | destroy_compound_gigantic_folio(folio, huge_page_order(h)); |
7f325a8d | 1797 | free_gigantic_folio(folio, huge_page_order(h)); |
944d9fec | 1798 | } else { |
6f6956cf | 1799 | __free_pages(&folio->page, huge_page_order(h)); |
944d9fec | 1800 | } |
6af2acb6 AL |
1801 | } |
1802 | ||
b65d4adb | 1803 | /* |
d6ef19e2 | 1804 | * As update_and_free_hugetlb_folio() can be called under any context, so we cannot |
b65d4adb MS |
1805 | * use GFP_KERNEL to allocate vmemmap pages. However, we can defer the |
1806 | * actual freeing in a workqueue to prevent from using GFP_ATOMIC to allocate | |
1807 | * the vmemmap pages. | |
1808 | * | |
1809 | * free_hpage_workfn() locklessly retrieves the linked list of pages to be | |
1810 | * freed and frees them one-by-one. As the page->mapping pointer is going | |
1811 | * to be cleared in free_hpage_workfn() anyway, it is reused as the llist_node | |
1812 | * structure of a lockless linked list of huge pages to be freed. | |
1813 | */ | |
1814 | static LLIST_HEAD(hpage_freelist); | |
1815 | ||
1816 | static void free_hpage_workfn(struct work_struct *work) | |
1817 | { | |
1818 | struct llist_node *node; | |
1819 | ||
1820 | node = llist_del_all(&hpage_freelist); | |
1821 | ||
1822 | while (node) { | |
3ec145f9 | 1823 | struct folio *folio; |
b65d4adb MS |
1824 | struct hstate *h; |
1825 | ||
3ec145f9 MWO |
1826 | folio = container_of((struct address_space **)node, |
1827 | struct folio, mapping); | |
b65d4adb | 1828 | node = node->next; |
3ec145f9 | 1829 | folio->mapping = NULL; |
b65d4adb | 1830 | /* |
affd26b1 SK |
1831 | * The VM_BUG_ON_FOLIO(!folio_test_hugetlb(folio), folio) in |
1832 | * folio_hstate() is going to trigger because a previous call to | |
9c5ccf2d MWO |
1833 | * remove_hugetlb_folio() will clear the hugetlb bit, so do |
1834 | * not use folio_hstate() directly. | |
b65d4adb | 1835 | */ |
3ec145f9 | 1836 | h = size_to_hstate(folio_size(folio)); |
b65d4adb | 1837 | |
3ec145f9 | 1838 | __update_and_free_hugetlb_folio(h, folio); |
b65d4adb MS |
1839 | |
1840 | cond_resched(); | |
1841 | } | |
1842 | } | |
1843 | static DECLARE_WORK(free_hpage_work, free_hpage_workfn); | |
1844 | ||
1845 | static inline void flush_free_hpage_work(struct hstate *h) | |
1846 | { | |
6213834c | 1847 | if (hugetlb_vmemmap_optimizable(h)) |
b65d4adb MS |
1848 | flush_work(&free_hpage_work); |
1849 | } | |
1850 | ||
d6ef19e2 | 1851 | static void update_and_free_hugetlb_folio(struct hstate *h, struct folio *folio, |
b65d4adb MS |
1852 | bool atomic) |
1853 | { | |
d6ef19e2 | 1854 | if (!folio_test_hugetlb_vmemmap_optimized(folio) || !atomic) { |
6f6956cf | 1855 | __update_and_free_hugetlb_folio(h, folio); |
b65d4adb MS |
1856 | return; |
1857 | } | |
1858 | ||
1859 | /* | |
1860 | * Defer freeing to avoid using GFP_ATOMIC to allocate vmemmap pages. | |
1861 | * | |
1862 | * Only call schedule_work() if hpage_freelist is previously | |
1863 | * empty. Otherwise, schedule_work() had been called but the workfn | |
1864 | * hasn't retrieved the list yet. | |
1865 | */ | |
d6ef19e2 | 1866 | if (llist_add((struct llist_node *)&folio->mapping, &hpage_freelist)) |
b65d4adb MS |
1867 | schedule_work(&free_hpage_work); |
1868 | } | |
1869 | ||
cfb8c750 MK |
1870 | static void bulk_vmemmap_restore_error(struct hstate *h, |
1871 | struct list_head *folio_list, | |
1872 | struct list_head *non_hvo_folios) | |
10c6ec49 | 1873 | { |
04bbfd84 | 1874 | struct folio *folio, *t_folio; |
10c6ec49 | 1875 | |
cfb8c750 MK |
1876 | if (!list_empty(non_hvo_folios)) { |
1877 | /* | |
1878 | * Free any restored hugetlb pages so that restore of the | |
1879 | * entire list can be retried. | |
1880 | * The idea is that in the common case of ENOMEM errors freeing | |
1881 | * hugetlb pages with vmemmap we will free up memory so that we | |
1882 | * can allocate vmemmap for more hugetlb pages. | |
1883 | */ | |
1884 | list_for_each_entry_safe(folio, t_folio, non_hvo_folios, lru) { | |
1885 | list_del(&folio->lru); | |
1886 | spin_lock_irq(&hugetlb_lock); | |
1887 | __clear_hugetlb_destructor(h, folio); | |
1888 | spin_unlock_irq(&hugetlb_lock); | |
1889 | update_and_free_hugetlb_folio(h, folio, false); | |
1890 | cond_resched(); | |
1891 | } | |
1892 | } else { | |
1893 | /* | |
1894 | * In the case where there are no folios which can be | |
1895 | * immediately freed, we loop through the list trying to restore | |
1896 | * vmemmap individually in the hope that someone elsewhere may | |
1897 | * have done something to cause success (such as freeing some | |
1898 | * memory). If unable to restore a hugetlb page, the hugetlb | |
1899 | * page is made a surplus page and removed from the list. | |
1900 | * If are able to restore vmemmap and free one hugetlb page, we | |
1901 | * quit processing the list to retry the bulk operation. | |
1902 | */ | |
1903 | list_for_each_entry_safe(folio, t_folio, folio_list, lru) | |
c5ad3233 | 1904 | if (hugetlb_vmemmap_restore_folio(h, folio)) { |
cfb8c750 | 1905 | list_del(&folio->lru); |
d2cf88c2 MK |
1906 | spin_lock_irq(&hugetlb_lock); |
1907 | add_hugetlb_folio(h, folio, true); | |
1908 | spin_unlock_irq(&hugetlb_lock); | |
cfb8c750 MK |
1909 | } else { |
1910 | list_del(&folio->lru); | |
1911 | spin_lock_irq(&hugetlb_lock); | |
1912 | __clear_hugetlb_destructor(h, folio); | |
1913 | spin_unlock_irq(&hugetlb_lock); | |
1914 | update_and_free_hugetlb_folio(h, folio, false); | |
1915 | cond_resched(); | |
1916 | break; | |
1917 | } | |
d2cf88c2 | 1918 | } |
cfb8c750 MK |
1919 | } |
1920 | ||
1921 | static void update_and_free_pages_bulk(struct hstate *h, | |
1922 | struct list_head *folio_list) | |
1923 | { | |
1924 | long ret; | |
1925 | struct folio *folio, *t_folio; | |
1926 | LIST_HEAD(non_hvo_folios); | |
d2cf88c2 MK |
1927 | |
1928 | /* | |
cfb8c750 MK |
1929 | * First allocate required vmemmmap (if necessary) for all folios. |
1930 | * Carefully handle errors and free up any available hugetlb pages | |
1931 | * in an effort to make forward progress. | |
d2cf88c2 | 1932 | */ |
cfb8c750 MK |
1933 | retry: |
1934 | ret = hugetlb_vmemmap_restore_folios(h, folio_list, &non_hvo_folios); | |
1935 | if (ret < 0) { | |
1936 | bulk_vmemmap_restore_error(h, folio_list, &non_hvo_folios); | |
1937 | goto retry; | |
1938 | } | |
1939 | ||
1940 | /* | |
1941 | * At this point, list should be empty, ret should be >= 0 and there | |
1942 | * should only be pages on the non_hvo_folios list. | |
1943 | * Do note that the non_hvo_folios list could be empty. | |
1944 | * Without HVO enabled, ret will be 0 and there is no need to call | |
1945 | * __clear_hugetlb_destructor as this was done previously. | |
1946 | */ | |
1947 | VM_WARN_ON(!list_empty(folio_list)); | |
1948 | VM_WARN_ON(ret < 0); | |
1949 | if (!list_empty(&non_hvo_folios) && ret) { | |
d2cf88c2 | 1950 | spin_lock_irq(&hugetlb_lock); |
cfb8c750 | 1951 | list_for_each_entry(folio, &non_hvo_folios, lru) |
d2cf88c2 MK |
1952 | __clear_hugetlb_destructor(h, folio); |
1953 | spin_unlock_irq(&hugetlb_lock); | |
1954 | } | |
1955 | ||
cfb8c750 | 1956 | list_for_each_entry_safe(folio, t_folio, &non_hvo_folios, lru) { |
d6ef19e2 | 1957 | update_and_free_hugetlb_folio(h, folio, false); |
10c6ec49 MK |
1958 | cond_resched(); |
1959 | } | |
1960 | } | |
1961 | ||
e5ff2159 AK |
1962 | struct hstate *size_to_hstate(unsigned long size) |
1963 | { | |
1964 | struct hstate *h; | |
1965 | ||
1966 | for_each_hstate(h) { | |
1967 | if (huge_page_size(h) == size) | |
1968 | return h; | |
1969 | } | |
1970 | return NULL; | |
1971 | } | |
1972 | ||
454a00c4 | 1973 | void free_huge_folio(struct folio *folio) |
27a85ef1 | 1974 | { |
a5516438 AK |
1975 | /* |
1976 | * Can't pass hstate in here because it is called from the | |
1977 | * compound page destructor. | |
1978 | */ | |
0356c4b9 SK |
1979 | struct hstate *h = folio_hstate(folio); |
1980 | int nid = folio_nid(folio); | |
1981 | struct hugepage_subpool *spool = hugetlb_folio_subpool(folio); | |
07443a85 | 1982 | bool restore_reserve; |
db71ef79 | 1983 | unsigned long flags; |
27a85ef1 | 1984 | |
0356c4b9 SK |
1985 | VM_BUG_ON_FOLIO(folio_ref_count(folio), folio); |
1986 | VM_BUG_ON_FOLIO(folio_mapcount(folio), folio); | |
8ace22bc | 1987 | |
0356c4b9 SK |
1988 | hugetlb_set_folio_subpool(folio, NULL); |
1989 | if (folio_test_anon(folio)) | |
1990 | __ClearPageAnonExclusive(&folio->page); | |
1991 | folio->mapping = NULL; | |
1992 | restore_reserve = folio_test_hugetlb_restore_reserve(folio); | |
1993 | folio_clear_hugetlb_restore_reserve(folio); | |
27a85ef1 | 1994 | |
1c5ecae3 | 1995 | /* |
d6995da3 | 1996 | * If HPageRestoreReserve was set on page, page allocation consumed a |
0919e1b6 MK |
1997 | * reservation. If the page was associated with a subpool, there |
1998 | * would have been a page reserved in the subpool before allocation | |
1999 | * via hugepage_subpool_get_pages(). Since we are 'restoring' the | |
6c26d310 | 2000 | * reservation, do not call hugepage_subpool_put_pages() as this will |
0919e1b6 | 2001 | * remove the reserved page from the subpool. |
1c5ecae3 | 2002 | */ |
0919e1b6 MK |
2003 | if (!restore_reserve) { |
2004 | /* | |
2005 | * A return code of zero implies that the subpool will be | |
2006 | * under its minimum size if the reservation is not restored | |
2007 | * after page is free. Therefore, force restore_reserve | |
2008 | * operation. | |
2009 | */ | |
2010 | if (hugepage_subpool_put_pages(spool, 1) == 0) | |
2011 | restore_reserve = true; | |
2012 | } | |
1c5ecae3 | 2013 | |
db71ef79 | 2014 | spin_lock_irqsave(&hugetlb_lock, flags); |
0356c4b9 | 2015 | folio_clear_hugetlb_migratable(folio); |
d4ab0316 SK |
2016 | hugetlb_cgroup_uncharge_folio(hstate_index(h), |
2017 | pages_per_huge_page(h), folio); | |
2018 | hugetlb_cgroup_uncharge_folio_rsvd(hstate_index(h), | |
2019 | pages_per_huge_page(h), folio); | |
8cba9576 | 2020 | mem_cgroup_uncharge(folio); |
07443a85 JK |
2021 | if (restore_reserve) |
2022 | h->resv_huge_pages++; | |
2023 | ||
0356c4b9 | 2024 | if (folio_test_hugetlb_temporary(folio)) { |
cfd5082b | 2025 | remove_hugetlb_folio(h, folio, false); |
db71ef79 | 2026 | spin_unlock_irqrestore(&hugetlb_lock, flags); |
d6ef19e2 | 2027 | update_and_free_hugetlb_folio(h, folio, true); |
ab5ac90a | 2028 | } else if (h->surplus_huge_pages_node[nid]) { |
0edaecfa | 2029 | /* remove the page from active list */ |
cfd5082b | 2030 | remove_hugetlb_folio(h, folio, true); |
db71ef79 | 2031 | spin_unlock_irqrestore(&hugetlb_lock, flags); |
d6ef19e2 | 2032 | update_and_free_hugetlb_folio(h, folio, true); |
7893d1d5 | 2033 | } else { |
454a00c4 | 2034 | arch_clear_hugepage_flags(&folio->page); |
240d67a8 | 2035 | enqueue_hugetlb_folio(h, folio); |
db71ef79 | 2036 | spin_unlock_irqrestore(&hugetlb_lock, flags); |
c77c0a8a | 2037 | } |
c77c0a8a WL |
2038 | } |
2039 | ||
d3d99fcc OS |
2040 | /* |
2041 | * Must be called with the hugetlb lock held | |
2042 | */ | |
2043 | static void __prep_account_new_huge_page(struct hstate *h, int nid) | |
2044 | { | |
2045 | lockdep_assert_held(&hugetlb_lock); | |
2046 | h->nr_huge_pages++; | |
2047 | h->nr_huge_pages_node[nid]++; | |
2048 | } | |
2049 | ||
d67e32f2 | 2050 | static void init_new_hugetlb_folio(struct hstate *h, struct folio *folio) |
b7ba30c6 | 2051 | { |
d8f5f7e4 | 2052 | folio_set_hugetlb(folio); |
de656ed3 | 2053 | INIT_LIST_HEAD(&folio->lru); |
de656ed3 SK |
2054 | hugetlb_set_folio_subpool(folio, NULL); |
2055 | set_hugetlb_cgroup(folio, NULL); | |
2056 | set_hugetlb_cgroup_rsvd(folio, NULL); | |
d3d99fcc OS |
2057 | } |
2058 | ||
d67e32f2 MK |
2059 | static void __prep_new_hugetlb_folio(struct hstate *h, struct folio *folio) |
2060 | { | |
2061 | init_new_hugetlb_folio(h, folio); | |
c5ad3233 | 2062 | hugetlb_vmemmap_optimize_folio(h, folio); |
d67e32f2 MK |
2063 | } |
2064 | ||
d1c60955 | 2065 | static void prep_new_hugetlb_folio(struct hstate *h, struct folio *folio, int nid) |
d3d99fcc | 2066 | { |
de656ed3 | 2067 | __prep_new_hugetlb_folio(h, folio); |
db71ef79 | 2068 | spin_lock_irq(&hugetlb_lock); |
d3d99fcc | 2069 | __prep_account_new_huge_page(h, nid); |
db71ef79 | 2070 | spin_unlock_irq(&hugetlb_lock); |
b7ba30c6 AK |
2071 | } |
2072 | ||
d1c60955 SK |
2073 | static bool __prep_compound_gigantic_folio(struct folio *folio, |
2074 | unsigned int order, bool demote) | |
20a0307c | 2075 | { |
7118fc29 | 2076 | int i, j; |
20a0307c | 2077 | int nr_pages = 1 << order; |
14455eab | 2078 | struct page *p; |
20a0307c | 2079 | |
d1c60955 | 2080 | __folio_clear_reserved(folio); |
2b21624f | 2081 | for (i = 0; i < nr_pages; i++) { |
d1c60955 | 2082 | p = folio_page(folio, i); |
14455eab | 2083 | |
ef5a22be AA |
2084 | /* |
2085 | * For gigantic hugepages allocated through bootmem at | |
2086 | * boot, it's safer to be consistent with the not-gigantic | |
2087 | * hugepages and clear the PG_reserved bit from all tail pages | |
7c8de358 | 2088 | * too. Otherwise drivers using get_user_pages() to access tail |
ef5a22be AA |
2089 | * pages may get the reference counting wrong if they see |
2090 | * PG_reserved set on a tail page (despite the head page not | |
2091 | * having PG_reserved set). Enforcing this consistency between | |
2092 | * head and tail pages allows drivers to optimize away a check | |
2093 | * on the head page when they need know if put_page() is needed | |
2094 | * after get_user_pages(). | |
2095 | */ | |
7fb0728a MK |
2096 | if (i != 0) /* head page cleared above */ |
2097 | __ClearPageReserved(p); | |
7118fc29 MK |
2098 | /* |
2099 | * Subtle and very unlikely | |
2100 | * | |
2101 | * Gigantic 'page allocators' such as memblock or cma will | |
2102 | * return a set of pages with each page ref counted. We need | |
2103 | * to turn this set of pages into a compound page with tail | |
2104 | * page ref counts set to zero. Code such as speculative page | |
2105 | * cache adding could take a ref on a 'to be' tail page. | |
2106 | * We need to respect any increased ref count, and only set | |
2107 | * the ref count to zero if count is currently 1. If count | |
416d85ed MK |
2108 | * is not 1, we return an error. An error return indicates |
2109 | * the set of pages can not be converted to a gigantic page. | |
2110 | * The caller who allocated the pages should then discard the | |
2111 | * pages using the appropriate free interface. | |
34d9e35b MK |
2112 | * |
2113 | * In the case of demote, the ref count will be zero. | |
7118fc29 | 2114 | */ |
34d9e35b MK |
2115 | if (!demote) { |
2116 | if (!page_ref_freeze(p, 1)) { | |
2117 | pr_warn("HugeTLB page can not be used due to unexpected inflated ref count\n"); | |
2118 | goto out_error; | |
2119 | } | |
2120 | } else { | |
2121 | VM_BUG_ON_PAGE(page_count(p), p); | |
7118fc29 | 2122 | } |
2b21624f | 2123 | if (i != 0) |
d1c60955 | 2124 | set_compound_head(p, &folio->page); |
20a0307c | 2125 | } |
e3b7bf97 TS |
2126 | __folio_set_head(folio); |
2127 | /* we rely on prep_new_hugetlb_folio to set the destructor */ | |
2128 | folio_set_order(folio, order); | |
46f27228 | 2129 | atomic_set(&folio->_entire_mapcount, -1); |
eec20426 | 2130 | atomic_set(&folio->_nr_pages_mapped, 0); |
94688e8e | 2131 | atomic_set(&folio->_pincount, 0); |
7118fc29 MK |
2132 | return true; |
2133 | ||
2134 | out_error: | |
2b21624f MK |
2135 | /* undo page modifications made above */ |
2136 | for (j = 0; j < i; j++) { | |
d1c60955 | 2137 | p = folio_page(folio, j); |
2b21624f MK |
2138 | if (j != 0) |
2139 | clear_compound_head(p); | |
7118fc29 MK |
2140 | set_page_refcounted(p); |
2141 | } | |
2142 | /* need to clear PG_reserved on remaining tail pages */ | |
14455eab | 2143 | for (; j < nr_pages; j++) { |
d1c60955 | 2144 | p = folio_page(folio, j); |
7118fc29 | 2145 | __ClearPageReserved(p); |
14455eab | 2146 | } |
7118fc29 | 2147 | return false; |
20a0307c WF |
2148 | } |
2149 | ||
d1c60955 SK |
2150 | static bool prep_compound_gigantic_folio(struct folio *folio, |
2151 | unsigned int order) | |
34d9e35b | 2152 | { |
d1c60955 | 2153 | return __prep_compound_gigantic_folio(folio, order, false); |
34d9e35b MK |
2154 | } |
2155 | ||
d1c60955 | 2156 | static bool prep_compound_gigantic_folio_for_demote(struct folio *folio, |
8531fc6f MK |
2157 | unsigned int order) |
2158 | { | |
d1c60955 | 2159 | return __prep_compound_gigantic_folio(folio, order, true); |
8531fc6f MK |
2160 | } |
2161 | ||
7795912c AM |
2162 | /* |
2163 | * PageHuge() only returns true for hugetlbfs pages, but not for normal or | |
2164 | * transparent huge pages. See the PageTransHuge() documentation for more | |
2165 | * details. | |
2166 | */ | |
29cfe755 | 2167 | int PageHuge(const struct page *page) |
20a0307c | 2168 | { |
29cfe755 | 2169 | const struct folio *folio; |
2d678c64 | 2170 | |
20a0307c WF |
2171 | if (!PageCompound(page)) |
2172 | return 0; | |
2d678c64 | 2173 | folio = page_folio(page); |
9c5ccf2d | 2174 | return folio_test_hugetlb(folio); |
20a0307c | 2175 | } |
43131e14 NH |
2176 | EXPORT_SYMBOL_GPL(PageHuge); |
2177 | ||
c0d0381a MK |
2178 | /* |
2179 | * Find and lock address space (mapping) in write mode. | |
2180 | * | |
336bf30e MK |
2181 | * Upon entry, the page is locked which means that page_mapping() is |
2182 | * stable. Due to locking order, we can only trylock_write. If we can | |
2183 | * not get the lock, simply return NULL to caller. | |
c0d0381a MK |
2184 | */ |
2185 | struct address_space *hugetlb_page_mapping_lock_write(struct page *hpage) | |
2186 | { | |
336bf30e | 2187 | struct address_space *mapping = page_mapping(hpage); |
c0d0381a | 2188 | |
c0d0381a MK |
2189 | if (!mapping) |
2190 | return mapping; | |
2191 | ||
c0d0381a MK |
2192 | if (i_mmap_trylock_write(mapping)) |
2193 | return mapping; | |
2194 | ||
336bf30e | 2195 | return NULL; |
c0d0381a MK |
2196 | } |
2197 | ||
19fc1a7e | 2198 | static struct folio *alloc_buddy_hugetlb_folio(struct hstate *h, |
f60858f9 MK |
2199 | gfp_t gfp_mask, int nid, nodemask_t *nmask, |
2200 | nodemask_t *node_alloc_noretry) | |
1da177e4 | 2201 | { |
af0fb9df | 2202 | int order = huge_page_order(h); |
1da177e4 | 2203 | struct page *page; |
f60858f9 | 2204 | bool alloc_try_hard = true; |
2b21624f | 2205 | bool retry = true; |
f96efd58 | 2206 | |
f60858f9 MK |
2207 | /* |
2208 | * By default we always try hard to allocate the page with | |
2209 | * __GFP_RETRY_MAYFAIL flag. However, if we are allocating pages in | |
2210 | * a loop (to adjust global huge page counts) and previous allocation | |
2211 | * failed, do not continue to try hard on the same node. Use the | |
2212 | * node_alloc_noretry bitmap to manage this state information. | |
2213 | */ | |
2214 | if (node_alloc_noretry && node_isset(nid, *node_alloc_noretry)) | |
2215 | alloc_try_hard = false; | |
2216 | gfp_mask |= __GFP_COMP|__GFP_NOWARN; | |
2217 | if (alloc_try_hard) | |
2218 | gfp_mask |= __GFP_RETRY_MAYFAIL; | |
af0fb9df MH |
2219 | if (nid == NUMA_NO_NODE) |
2220 | nid = numa_mem_id(); | |
2b21624f | 2221 | retry: |
84172f4b | 2222 | page = __alloc_pages(gfp_mask, order, nid, nmask); |
2b21624f MK |
2223 | |
2224 | /* Freeze head page */ | |
2225 | if (page && !page_ref_freeze(page, 1)) { | |
2226 | __free_pages(page, order); | |
2227 | if (retry) { /* retry once */ | |
2228 | retry = false; | |
2229 | goto retry; | |
2230 | } | |
2231 | /* WOW! twice in a row. */ | |
2232 | pr_warn("HugeTLB head page unexpected inflated ref count\n"); | |
2233 | page = NULL; | |
2234 | } | |
2235 | ||
f60858f9 MK |
2236 | /* |
2237 | * If we did not specify __GFP_RETRY_MAYFAIL, but still got a page this | |
2238 | * indicates an overall state change. Clear bit so that we resume | |
2239 | * normal 'try hard' allocations. | |
2240 | */ | |
2241 | if (node_alloc_noretry && page && !alloc_try_hard) | |
2242 | node_clear(nid, *node_alloc_noretry); | |
2243 | ||
2244 | /* | |
2245 | * If we tried hard to get a page but failed, set bit so that | |
2246 | * subsequent attempts will not try as hard until there is an | |
2247 | * overall state change. | |
2248 | */ | |
2249 | if (node_alloc_noretry && !page && alloc_try_hard) | |
2250 | node_set(nid, *node_alloc_noretry); | |
2251 | ||
19fc1a7e SK |
2252 | if (!page) { |
2253 | __count_vm_event(HTLB_BUDDY_PGALLOC_FAIL); | |
2254 | return NULL; | |
2255 | } | |
2256 | ||
2257 | __count_vm_event(HTLB_BUDDY_PGALLOC); | |
2258 | return page_folio(page); | |
63b4613c NA |
2259 | } |
2260 | ||
d67e32f2 MK |
2261 | static struct folio *__alloc_fresh_hugetlb_folio(struct hstate *h, |
2262 | gfp_t gfp_mask, int nid, nodemask_t *nmask, | |
2263 | nodemask_t *node_alloc_noretry) | |
0c397dae | 2264 | { |
7f325a8d | 2265 | struct folio *folio; |
7118fc29 | 2266 | bool retry = false; |
0c397dae | 2267 | |
7118fc29 | 2268 | retry: |
0c397dae | 2269 | if (hstate_is_gigantic(h)) |
19fc1a7e | 2270 | folio = alloc_gigantic_folio(h, gfp_mask, nid, nmask); |
0c397dae | 2271 | else |
19fc1a7e | 2272 | folio = alloc_buddy_hugetlb_folio(h, gfp_mask, |
f60858f9 | 2273 | nid, nmask, node_alloc_noretry); |
19fc1a7e | 2274 | if (!folio) |
0c397dae | 2275 | return NULL; |
d67e32f2 | 2276 | |
7118fc29 | 2277 | if (hstate_is_gigantic(h)) { |
d1c60955 | 2278 | if (!prep_compound_gigantic_folio(folio, huge_page_order(h))) { |
7118fc29 MK |
2279 | /* |
2280 | * Rare failure to convert pages to compound page. | |
2281 | * Free pages and try again - ONCE! | |
2282 | */ | |
7f325a8d | 2283 | free_gigantic_folio(folio, huge_page_order(h)); |
7118fc29 MK |
2284 | if (!retry) { |
2285 | retry = true; | |
2286 | goto retry; | |
2287 | } | |
7118fc29 MK |
2288 | return NULL; |
2289 | } | |
2290 | } | |
0c397dae | 2291 | |
19fc1a7e | 2292 | return folio; |
0c397dae MH |
2293 | } |
2294 | ||
d67e32f2 MK |
2295 | static struct folio *only_alloc_fresh_hugetlb_folio(struct hstate *h, |
2296 | gfp_t gfp_mask, int nid, nodemask_t *nmask, | |
2297 | nodemask_t *node_alloc_noretry) | |
2298 | { | |
2299 | struct folio *folio; | |
2300 | ||
2301 | folio = __alloc_fresh_hugetlb_folio(h, gfp_mask, nid, nmask, | |
2302 | node_alloc_noretry); | |
2303 | if (folio) | |
2304 | init_new_hugetlb_folio(h, folio); | |
2305 | return folio; | |
2306 | } | |
2307 | ||
af0fb9df | 2308 | /* |
d67e32f2 MK |
2309 | * Common helper to allocate a fresh hugetlb page. All specific allocators |
2310 | * should use this function to get new hugetlb pages | |
2311 | * | |
2312 | * Note that returned page is 'frozen': ref count of head page and all tail | |
2313 | * pages is zero. | |
af0fb9df | 2314 | */ |
d67e32f2 MK |
2315 | static struct folio *alloc_fresh_hugetlb_folio(struct hstate *h, |
2316 | gfp_t gfp_mask, int nid, nodemask_t *nmask, | |
2317 | nodemask_t *node_alloc_noretry) | |
b2261026 | 2318 | { |
19fc1a7e | 2319 | struct folio *folio; |
d67e32f2 MK |
2320 | |
2321 | folio = __alloc_fresh_hugetlb_folio(h, gfp_mask, nid, nmask, | |
2322 | node_alloc_noretry); | |
2323 | if (!folio) | |
2324 | return NULL; | |
2325 | ||
2326 | prep_new_hugetlb_folio(h, folio, folio_nid(folio)); | |
2327 | return folio; | |
2328 | } | |
2329 | ||
2330 | static void prep_and_add_allocated_folios(struct hstate *h, | |
2331 | struct list_head *folio_list) | |
2332 | { | |
2333 | unsigned long flags; | |
2334 | struct folio *folio, *tmp_f; | |
2335 | ||
79359d6d MK |
2336 | /* Send list for bulk vmemmap optimization processing */ |
2337 | hugetlb_vmemmap_optimize_folios(h, folio_list); | |
2338 | ||
d67e32f2 MK |
2339 | /* Add all new pool pages to free lists in one lock cycle */ |
2340 | spin_lock_irqsave(&hugetlb_lock, flags); | |
2341 | list_for_each_entry_safe(folio, tmp_f, folio_list, lru) { | |
2342 | __prep_account_new_huge_page(h, folio_nid(folio)); | |
2343 | enqueue_hugetlb_folio(h, folio); | |
2344 | } | |
2345 | spin_unlock_irqrestore(&hugetlb_lock, flags); | |
2346 | } | |
2347 | ||
2348 | /* | |
2349 | * Allocates a fresh hugetlb page in a node interleaved manner. The page | |
2350 | * will later be added to the appropriate hugetlb pool. | |
2351 | */ | |
2352 | static struct folio *alloc_pool_huge_folio(struct hstate *h, | |
2353 | nodemask_t *nodes_allowed, | |
2e73ff23 GL |
2354 | nodemask_t *node_alloc_noretry, |
2355 | int *next_node) | |
d67e32f2 | 2356 | { |
af0fb9df | 2357 | gfp_t gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE; |
d67e32f2 | 2358 | int nr_nodes, node; |
b2261026 | 2359 | |
2e73ff23 | 2360 | for_each_node_mask_to_alloc(next_node, nr_nodes, node, nodes_allowed) { |
d67e32f2 MK |
2361 | struct folio *folio; |
2362 | ||
2363 | folio = only_alloc_fresh_hugetlb_folio(h, gfp_mask, node, | |
19fc1a7e | 2364 | nodes_allowed, node_alloc_noretry); |
d67e32f2 MK |
2365 | if (folio) |
2366 | return folio; | |
b2261026 JK |
2367 | } |
2368 | ||
d67e32f2 | 2369 | return NULL; |
b2261026 JK |
2370 | } |
2371 | ||
e8c5c824 | 2372 | /* |
10c6ec49 MK |
2373 | * Remove huge page from pool from next node to free. Attempt to keep |
2374 | * persistent huge pages more or less balanced over allowed nodes. | |
2375 | * This routine only 'removes' the hugetlb page. The caller must make | |
2376 | * an additional call to free the page to low level allocators. | |
e8c5c824 LS |
2377 | * Called with hugetlb_lock locked. |
2378 | */ | |
d5b43e96 MWO |
2379 | static struct folio *remove_pool_hugetlb_folio(struct hstate *h, |
2380 | nodemask_t *nodes_allowed, bool acct_surplus) | |
e8c5c824 | 2381 | { |
b2261026 | 2382 | int nr_nodes, node; |
04bbfd84 | 2383 | struct folio *folio = NULL; |
e8c5c824 | 2384 | |
9487ca60 | 2385 | lockdep_assert_held(&hugetlb_lock); |
b2261026 | 2386 | for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { |
685f3457 LS |
2387 | /* |
2388 | * If we're returning unused surplus pages, only examine | |
2389 | * nodes with surplus pages. | |
2390 | */ | |
b2261026 JK |
2391 | if ((!acct_surplus || h->surplus_huge_pages_node[node]) && |
2392 | !list_empty(&h->hugepage_freelists[node])) { | |
04bbfd84 MWO |
2393 | folio = list_entry(h->hugepage_freelists[node].next, |
2394 | struct folio, lru); | |
cfd5082b | 2395 | remove_hugetlb_folio(h, folio, acct_surplus); |
9a76db09 | 2396 | break; |
e8c5c824 | 2397 | } |
b2261026 | 2398 | } |
e8c5c824 | 2399 | |
d5b43e96 | 2400 | return folio; |
e8c5c824 LS |
2401 | } |
2402 | ||
c8721bbb NH |
2403 | /* |
2404 | * Dissolve a given free hugepage into free buddy pages. This function does | |
faf53def NH |
2405 | * nothing for in-use hugepages and non-hugepages. |
2406 | * This function returns values like below: | |
2407 | * | |
ad2fa371 MS |
2408 | * -ENOMEM: failed to allocate vmemmap pages to free the freed hugepages |
2409 | * when the system is under memory pressure and the feature of | |
2410 | * freeing unused vmemmap pages associated with each hugetlb page | |
2411 | * is enabled. | |
2412 | * -EBUSY: failed to dissolved free hugepages or the hugepage is in-use | |
2413 | * (allocated or reserved.) | |
2414 | * 0: successfully dissolved free hugepages or the page is not a | |
2415 | * hugepage (considered as already dissolved) | |
c8721bbb | 2416 | */ |
c3114a84 | 2417 | int dissolve_free_huge_page(struct page *page) |
c8721bbb | 2418 | { |
6bc9b564 | 2419 | int rc = -EBUSY; |
1a7cdab5 | 2420 | struct folio *folio = page_folio(page); |
082d5b6b | 2421 | |
7ffddd49 | 2422 | retry: |
faf53def | 2423 | /* Not to disrupt normal path by vainly holding hugetlb_lock */ |
1a7cdab5 | 2424 | if (!folio_test_hugetlb(folio)) |
faf53def NH |
2425 | return 0; |
2426 | ||
db71ef79 | 2427 | spin_lock_irq(&hugetlb_lock); |
1a7cdab5 | 2428 | if (!folio_test_hugetlb(folio)) { |
faf53def NH |
2429 | rc = 0; |
2430 | goto out; | |
2431 | } | |
2432 | ||
1a7cdab5 SK |
2433 | if (!folio_ref_count(folio)) { |
2434 | struct hstate *h = folio_hstate(folio); | |
8346d69d | 2435 | if (!available_huge_pages(h)) |
082d5b6b | 2436 | goto out; |
7ffddd49 MS |
2437 | |
2438 | /* | |
2439 | * We should make sure that the page is already on the free list | |
2440 | * when it is dissolved. | |
2441 | */ | |
1a7cdab5 | 2442 | if (unlikely(!folio_test_hugetlb_freed(folio))) { |
db71ef79 | 2443 | spin_unlock_irq(&hugetlb_lock); |
7ffddd49 MS |
2444 | cond_resched(); |
2445 | ||
2446 | /* | |
2447 | * Theoretically, we should return -EBUSY when we | |
2448 | * encounter this race. In fact, we have a chance | |
2449 | * to successfully dissolve the page if we do a | |
2450 | * retry. Because the race window is quite small. | |
2451 | * If we seize this opportunity, it is an optimization | |
2452 | * for increasing the success rate of dissolving page. | |
2453 | */ | |
2454 | goto retry; | |
2455 | } | |
2456 | ||
cfd5082b | 2457 | remove_hugetlb_folio(h, folio, false); |
c1470b33 | 2458 | h->max_huge_pages--; |
db71ef79 | 2459 | spin_unlock_irq(&hugetlb_lock); |
ad2fa371 MS |
2460 | |
2461 | /* | |
d6ef19e2 SK |
2462 | * Normally update_and_free_hugtlb_folio will allocate required vmemmmap |
2463 | * before freeing the page. update_and_free_hugtlb_folio will fail to | |
ad2fa371 MS |
2464 | * free the page if it can not allocate required vmemmap. We |
2465 | * need to adjust max_huge_pages if the page is not freed. | |
2466 | * Attempt to allocate vmemmmap here so that we can take | |
2467 | * appropriate action on failure. | |
30a89adf MK |
2468 | * |
2469 | * The folio_test_hugetlb check here is because | |
2470 | * remove_hugetlb_folio will clear hugetlb folio flag for | |
2471 | * non-vmemmap optimized hugetlb folios. | |
ad2fa371 | 2472 | */ |
30a89adf | 2473 | if (folio_test_hugetlb(folio)) { |
c5ad3233 | 2474 | rc = hugetlb_vmemmap_restore_folio(h, folio); |
30a89adf MK |
2475 | if (rc) { |
2476 | spin_lock_irq(&hugetlb_lock); | |
2477 | add_hugetlb_folio(h, folio, false); | |
2478 | h->max_huge_pages++; | |
2479 | goto out; | |
2480 | } | |
2481 | } else | |
2482 | rc = 0; | |
ad2fa371 | 2483 | |
30a89adf | 2484 | update_and_free_hugetlb_folio(h, folio, false); |
ad2fa371 | 2485 | return rc; |
c8721bbb | 2486 | } |
082d5b6b | 2487 | out: |
db71ef79 | 2488 | spin_unlock_irq(&hugetlb_lock); |
082d5b6b | 2489 | return rc; |
c8721bbb NH |
2490 | } |
2491 | ||
2492 | /* | |
2493 | * Dissolve free hugepages in a given pfn range. Used by memory hotplug to | |
2494 | * make specified memory blocks removable from the system. | |
2247bb33 GS |
2495 | * Note that this will dissolve a free gigantic hugepage completely, if any |
2496 | * part of it lies within the given range. | |
082d5b6b GS |
2497 | * Also note that if dissolve_free_huge_page() returns with an error, all |
2498 | * free hugepages that were dissolved before that error are lost. | |
c8721bbb | 2499 | */ |
082d5b6b | 2500 | int dissolve_free_huge_pages(unsigned long start_pfn, unsigned long end_pfn) |
c8721bbb | 2501 | { |
c8721bbb | 2502 | unsigned long pfn; |
eb03aa00 | 2503 | struct page *page; |
082d5b6b | 2504 | int rc = 0; |
dc2628f3 MS |
2505 | unsigned int order; |
2506 | struct hstate *h; | |
c8721bbb | 2507 | |
d0177639 | 2508 | if (!hugepages_supported()) |
082d5b6b | 2509 | return rc; |
d0177639 | 2510 | |
dc2628f3 MS |
2511 | order = huge_page_order(&default_hstate); |
2512 | for_each_hstate(h) | |
2513 | order = min(order, huge_page_order(h)); | |
2514 | ||
2515 | for (pfn = start_pfn; pfn < end_pfn; pfn += 1 << order) { | |
eb03aa00 | 2516 | page = pfn_to_page(pfn); |
faf53def NH |
2517 | rc = dissolve_free_huge_page(page); |
2518 | if (rc) | |
2519 | break; | |
eb03aa00 | 2520 | } |
082d5b6b GS |
2521 | |
2522 | return rc; | |
c8721bbb NH |
2523 | } |
2524 | ||
ab5ac90a MH |
2525 | /* |
2526 | * Allocates a fresh surplus page from the page allocator. | |
2527 | */ | |
3a740e8b SK |
2528 | static struct folio *alloc_surplus_hugetlb_folio(struct hstate *h, |
2529 | gfp_t gfp_mask, int nid, nodemask_t *nmask) | |
7893d1d5 | 2530 | { |
19fc1a7e | 2531 | struct folio *folio = NULL; |
7893d1d5 | 2532 | |
bae7f4ae | 2533 | if (hstate_is_gigantic(h)) |
aa888a74 AK |
2534 | return NULL; |
2535 | ||
db71ef79 | 2536 | spin_lock_irq(&hugetlb_lock); |
9980d744 MH |
2537 | if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages) |
2538 | goto out_unlock; | |
db71ef79 | 2539 | spin_unlock_irq(&hugetlb_lock); |
d1c3fb1f | 2540 | |
19fc1a7e SK |
2541 | folio = alloc_fresh_hugetlb_folio(h, gfp_mask, nid, nmask, NULL); |
2542 | if (!folio) | |
0c397dae | 2543 | return NULL; |
d1c3fb1f | 2544 | |
db71ef79 | 2545 | spin_lock_irq(&hugetlb_lock); |
9980d744 MH |
2546 | /* |
2547 | * We could have raced with the pool size change. | |
2548 | * Double check that and simply deallocate the new page | |
2549 | * if we would end up overcommiting the surpluses. Abuse | |
454a00c4 | 2550 | * temporary page to workaround the nasty free_huge_folio |
9980d744 MH |
2551 | * codeflow |
2552 | */ | |
2553 | if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages) { | |
19fc1a7e | 2554 | folio_set_hugetlb_temporary(folio); |
db71ef79 | 2555 | spin_unlock_irq(&hugetlb_lock); |
454a00c4 | 2556 | free_huge_folio(folio); |
2bf753e6 | 2557 | return NULL; |
7893d1d5 | 2558 | } |
9980d744 | 2559 | |
b65a4eda | 2560 | h->surplus_huge_pages++; |
19fc1a7e | 2561 | h->surplus_huge_pages_node[folio_nid(folio)]++; |
b65a4eda | 2562 | |
9980d744 | 2563 | out_unlock: |
db71ef79 | 2564 | spin_unlock_irq(&hugetlb_lock); |
7893d1d5 | 2565 | |
3a740e8b | 2566 | return folio; |
7893d1d5 AL |
2567 | } |
2568 | ||
e37d3e83 | 2569 | static struct folio *alloc_migrate_hugetlb_folio(struct hstate *h, gfp_t gfp_mask, |
9a4e9f3b | 2570 | int nid, nodemask_t *nmask) |
ab5ac90a | 2571 | { |
19fc1a7e | 2572 | struct folio *folio; |
ab5ac90a MH |
2573 | |
2574 | if (hstate_is_gigantic(h)) | |
2575 | return NULL; | |
2576 | ||
19fc1a7e SK |
2577 | folio = alloc_fresh_hugetlb_folio(h, gfp_mask, nid, nmask, NULL); |
2578 | if (!folio) | |
ab5ac90a MH |
2579 | return NULL; |
2580 | ||
2b21624f | 2581 | /* fresh huge pages are frozen */ |
19fc1a7e | 2582 | folio_ref_unfreeze(folio, 1); |
ab5ac90a MH |
2583 | /* |
2584 | * We do not account these pages as surplus because they are only | |
2585 | * temporary and will be released properly on the last reference | |
2586 | */ | |
19fc1a7e | 2587 | folio_set_hugetlb_temporary(folio); |
ab5ac90a | 2588 | |
e37d3e83 | 2589 | return folio; |
ab5ac90a MH |
2590 | } |
2591 | ||
099730d6 DH |
2592 | /* |
2593 | * Use the VMA's mpolicy to allocate a huge page from the buddy. | |
2594 | */ | |
e0ec90ee | 2595 | static |
ff7d853b | 2596 | struct folio *alloc_buddy_hugetlb_folio_with_mpol(struct hstate *h, |
099730d6 DH |
2597 | struct vm_area_struct *vma, unsigned long addr) |
2598 | { | |
3a740e8b | 2599 | struct folio *folio = NULL; |
aaf14e40 MH |
2600 | struct mempolicy *mpol; |
2601 | gfp_t gfp_mask = htlb_alloc_mask(h); | |
2602 | int nid; | |
2603 | nodemask_t *nodemask; | |
2604 | ||
2605 | nid = huge_node(vma, addr, gfp_mask, &mpol, &nodemask); | |
cfcaa66f BW |
2606 | if (mpol_is_preferred_many(mpol)) { |
2607 | gfp_t gfp = gfp_mask | __GFP_NOWARN; | |
2608 | ||
2609 | gfp &= ~(__GFP_DIRECT_RECLAIM | __GFP_NOFAIL); | |
3a740e8b | 2610 | folio = alloc_surplus_hugetlb_folio(h, gfp, nid, nodemask); |
aaf14e40 | 2611 | |
cfcaa66f BW |
2612 | /* Fallback to all nodes if page==NULL */ |
2613 | nodemask = NULL; | |
2614 | } | |
2615 | ||
3a740e8b SK |
2616 | if (!folio) |
2617 | folio = alloc_surplus_hugetlb_folio(h, gfp_mask, nid, nodemask); | |
cfcaa66f | 2618 | mpol_cond_put(mpol); |
ff7d853b | 2619 | return folio; |
099730d6 DH |
2620 | } |
2621 | ||
e37d3e83 SK |
2622 | /* folio migration callback function */ |
2623 | struct folio *alloc_hugetlb_folio_nodemask(struct hstate *h, int preferred_nid, | |
d92bbc27 | 2624 | nodemask_t *nmask, gfp_t gfp_mask) |
4db9b2ef | 2625 | { |
db71ef79 | 2626 | spin_lock_irq(&hugetlb_lock); |
8346d69d | 2627 | if (available_huge_pages(h)) { |
a36f1e90 | 2628 | struct folio *folio; |
3e59fcb0 | 2629 | |
a36f1e90 SK |
2630 | folio = dequeue_hugetlb_folio_nodemask(h, gfp_mask, |
2631 | preferred_nid, nmask); | |
2632 | if (folio) { | |
db71ef79 | 2633 | spin_unlock_irq(&hugetlb_lock); |
e37d3e83 | 2634 | return folio; |
4db9b2ef MH |
2635 | } |
2636 | } | |
db71ef79 | 2637 | spin_unlock_irq(&hugetlb_lock); |
4db9b2ef | 2638 | |
e37d3e83 | 2639 | return alloc_migrate_hugetlb_folio(h, gfp_mask, preferred_nid, nmask); |
4db9b2ef MH |
2640 | } |
2641 | ||
e4e574b7 | 2642 | /* |
25985edc | 2643 | * Increase the hugetlb pool such that it can accommodate a reservation |
e4e574b7 AL |
2644 | * of size 'delta'. |
2645 | */ | |
0a4f3d1b | 2646 | static int gather_surplus_pages(struct hstate *h, long delta) |
1b2a1e7b | 2647 | __must_hold(&hugetlb_lock) |
e4e574b7 | 2648 | { |
34665341 | 2649 | LIST_HEAD(surplus_list); |
454a00c4 | 2650 | struct folio *folio, *tmp; |
0a4f3d1b LX |
2651 | int ret; |
2652 | long i; | |
2653 | long needed, allocated; | |
28073b02 | 2654 | bool alloc_ok = true; |
e4e574b7 | 2655 | |
9487ca60 | 2656 | lockdep_assert_held(&hugetlb_lock); |
a5516438 | 2657 | needed = (h->resv_huge_pages + delta) - h->free_huge_pages; |
ac09b3a1 | 2658 | if (needed <= 0) { |
a5516438 | 2659 | h->resv_huge_pages += delta; |
e4e574b7 | 2660 | return 0; |
ac09b3a1 | 2661 | } |
e4e574b7 AL |
2662 | |
2663 | allocated = 0; | |
e4e574b7 AL |
2664 | |
2665 | ret = -ENOMEM; | |
2666 | retry: | |
db71ef79 | 2667 | spin_unlock_irq(&hugetlb_lock); |
e4e574b7 | 2668 | for (i = 0; i < needed; i++) { |
3a740e8b | 2669 | folio = alloc_surplus_hugetlb_folio(h, htlb_alloc_mask(h), |
2b21624f | 2670 | NUMA_NO_NODE, NULL); |
3a740e8b | 2671 | if (!folio) { |
28073b02 HD |
2672 | alloc_ok = false; |
2673 | break; | |
2674 | } | |
3a740e8b | 2675 | list_add(&folio->lru, &surplus_list); |
69ed779a | 2676 | cond_resched(); |
e4e574b7 | 2677 | } |
28073b02 | 2678 | allocated += i; |
e4e574b7 AL |
2679 | |
2680 | /* | |
2681 | * After retaking hugetlb_lock, we need to recalculate 'needed' | |
2682 | * because either resv_huge_pages or free_huge_pages may have changed. | |
2683 | */ | |
db71ef79 | 2684 | spin_lock_irq(&hugetlb_lock); |
a5516438 AK |
2685 | needed = (h->resv_huge_pages + delta) - |
2686 | (h->free_huge_pages + allocated); | |
28073b02 HD |
2687 | if (needed > 0) { |
2688 | if (alloc_ok) | |
2689 | goto retry; | |
2690 | /* | |
2691 | * We were not able to allocate enough pages to | |
2692 | * satisfy the entire reservation so we free what | |
2693 | * we've allocated so far. | |
2694 | */ | |
2695 | goto free; | |
2696 | } | |
e4e574b7 AL |
2697 | /* |
2698 | * The surplus_list now contains _at_least_ the number of extra pages | |
25985edc | 2699 | * needed to accommodate the reservation. Add the appropriate number |
e4e574b7 | 2700 | * of pages to the hugetlb pool and free the extras back to the buddy |
ac09b3a1 AL |
2701 | * allocator. Commit the entire reservation here to prevent another |
2702 | * process from stealing the pages as they are added to the pool but | |
2703 | * before they are reserved. | |
e4e574b7 AL |
2704 | */ |
2705 | needed += allocated; | |
a5516438 | 2706 | h->resv_huge_pages += delta; |
e4e574b7 | 2707 | ret = 0; |
a9869b83 | 2708 | |
19fc3f0a | 2709 | /* Free the needed pages to the hugetlb pool */ |
454a00c4 | 2710 | list_for_each_entry_safe(folio, tmp, &surplus_list, lru) { |
19fc3f0a AL |
2711 | if ((--needed) < 0) |
2712 | break; | |
b65a4eda | 2713 | /* Add the page to the hugetlb allocator */ |
454a00c4 | 2714 | enqueue_hugetlb_folio(h, folio); |
19fc3f0a | 2715 | } |
28073b02 | 2716 | free: |
db71ef79 | 2717 | spin_unlock_irq(&hugetlb_lock); |
19fc3f0a | 2718 | |
b65a4eda MK |
2719 | /* |
2720 | * Free unnecessary surplus pages to the buddy allocator. | |
454a00c4 | 2721 | * Pages have no ref count, call free_huge_folio directly. |
b65a4eda | 2722 | */ |
454a00c4 MWO |
2723 | list_for_each_entry_safe(folio, tmp, &surplus_list, lru) |
2724 | free_huge_folio(folio); | |
db71ef79 | 2725 | spin_lock_irq(&hugetlb_lock); |
e4e574b7 AL |
2726 | |
2727 | return ret; | |
2728 | } | |
2729 | ||
2730 | /* | |
e5bbc8a6 MK |
2731 | * This routine has two main purposes: |
2732 | * 1) Decrement the reservation count (resv_huge_pages) by the value passed | |
2733 | * in unused_resv_pages. This corresponds to the prior adjustments made | |
2734 | * to the associated reservation map. | |
2735 | * 2) Free any unused surplus pages that may have been allocated to satisfy | |
2736 | * the reservation. As many as unused_resv_pages may be freed. | |
e4e574b7 | 2737 | */ |
a5516438 AK |
2738 | static void return_unused_surplus_pages(struct hstate *h, |
2739 | unsigned long unused_resv_pages) | |
e4e574b7 | 2740 | { |
e4e574b7 | 2741 | unsigned long nr_pages; |
10c6ec49 MK |
2742 | LIST_HEAD(page_list); |
2743 | ||
9487ca60 | 2744 | lockdep_assert_held(&hugetlb_lock); |
10c6ec49 MK |
2745 | /* Uncommit the reservation */ |
2746 | h->resv_huge_pages -= unused_resv_pages; | |
e4e574b7 | 2747 | |
c0531714 | 2748 | if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) |
e5bbc8a6 | 2749 | goto out; |
aa888a74 | 2750 | |
e5bbc8a6 MK |
2751 | /* |
2752 | * Part (or even all) of the reservation could have been backed | |
2753 | * by pre-allocated pages. Only free surplus pages. | |
2754 | */ | |
a5516438 | 2755 | nr_pages = min(unused_resv_pages, h->surplus_huge_pages); |
e4e574b7 | 2756 | |
685f3457 LS |
2757 | /* |
2758 | * We want to release as many surplus pages as possible, spread | |
9b5e5d0f LS |
2759 | * evenly across all nodes with memory. Iterate across these nodes |
2760 | * until we can no longer free unreserved surplus pages. This occurs | |
2761 | * when the nodes with surplus pages have no free pages. | |
d5b43e96 | 2762 | * remove_pool_hugetlb_folio() will balance the freed pages across the |
9b5e5d0f | 2763 | * on-line nodes with memory and will handle the hstate accounting. |
685f3457 LS |
2764 | */ |
2765 | while (nr_pages--) { | |
d5b43e96 MWO |
2766 | struct folio *folio; |
2767 | ||
2768 | folio = remove_pool_hugetlb_folio(h, &node_states[N_MEMORY], 1); | |
2769 | if (!folio) | |
e5bbc8a6 | 2770 | goto out; |
10c6ec49 | 2771 | |
d5b43e96 | 2772 | list_add(&folio->lru, &page_list); |
e4e574b7 | 2773 | } |
e5bbc8a6 MK |
2774 | |
2775 | out: | |
db71ef79 | 2776 | spin_unlock_irq(&hugetlb_lock); |
10c6ec49 | 2777 | update_and_free_pages_bulk(h, &page_list); |
db71ef79 | 2778 | spin_lock_irq(&hugetlb_lock); |
e4e574b7 AL |
2779 | } |
2780 | ||
5e911373 | 2781 | |
c37f9fb1 | 2782 | /* |
feba16e2 | 2783 | * vma_needs_reservation, vma_commit_reservation and vma_end_reservation |
5e911373 | 2784 | * are used by the huge page allocation routines to manage reservations. |
cf3ad20b MK |
2785 | * |
2786 | * vma_needs_reservation is called to determine if the huge page at addr | |
2787 | * within the vma has an associated reservation. If a reservation is | |
2788 | * needed, the value 1 is returned. The caller is then responsible for | |
2789 | * managing the global reservation and subpool usage counts. After | |
2790 | * the huge page has been allocated, vma_commit_reservation is called | |
feba16e2 MK |
2791 | * to add the page to the reservation map. If the page allocation fails, |
2792 | * the reservation must be ended instead of committed. vma_end_reservation | |
2793 | * is called in such cases. | |
cf3ad20b MK |
2794 | * |
2795 | * In the normal case, vma_commit_reservation returns the same value | |
2796 | * as the preceding vma_needs_reservation call. The only time this | |
2797 | * is not the case is if a reserve map was changed between calls. It | |
2798 | * is the responsibility of the caller to notice the difference and | |
2799 | * take appropriate action. | |
96b96a96 MK |
2800 | * |
2801 | * vma_add_reservation is used in error paths where a reservation must | |
2802 | * be restored when a newly allocated huge page must be freed. It is | |
2803 | * to be called after calling vma_needs_reservation to determine if a | |
2804 | * reservation exists. | |
846be085 MK |
2805 | * |
2806 | * vma_del_reservation is used in error paths where an entry in the reserve | |
2807 | * map was created during huge page allocation and must be removed. It is to | |
2808 | * be called after calling vma_needs_reservation to determine if a reservation | |
2809 | * exists. | |
c37f9fb1 | 2810 | */ |
5e911373 MK |
2811 | enum vma_resv_mode { |
2812 | VMA_NEEDS_RESV, | |
2813 | VMA_COMMIT_RESV, | |
feba16e2 | 2814 | VMA_END_RESV, |
96b96a96 | 2815 | VMA_ADD_RESV, |
846be085 | 2816 | VMA_DEL_RESV, |
5e911373 | 2817 | }; |
cf3ad20b MK |
2818 | static long __vma_reservation_common(struct hstate *h, |
2819 | struct vm_area_struct *vma, unsigned long addr, | |
5e911373 | 2820 | enum vma_resv_mode mode) |
c37f9fb1 | 2821 | { |
4e35f483 JK |
2822 | struct resv_map *resv; |
2823 | pgoff_t idx; | |
cf3ad20b | 2824 | long ret; |
0db9d74e | 2825 | long dummy_out_regions_needed; |
c37f9fb1 | 2826 | |
4e35f483 JK |
2827 | resv = vma_resv_map(vma); |
2828 | if (!resv) | |
84afd99b | 2829 | return 1; |
c37f9fb1 | 2830 | |
4e35f483 | 2831 | idx = vma_hugecache_offset(h, vma, addr); |
5e911373 MK |
2832 | switch (mode) { |
2833 | case VMA_NEEDS_RESV: | |
0db9d74e MA |
2834 | ret = region_chg(resv, idx, idx + 1, &dummy_out_regions_needed); |
2835 | /* We assume that vma_reservation_* routines always operate on | |
2836 | * 1 page, and that adding to resv map a 1 page entry can only | |
2837 | * ever require 1 region. | |
2838 | */ | |
2839 | VM_BUG_ON(dummy_out_regions_needed != 1); | |
5e911373 MK |
2840 | break; |
2841 | case VMA_COMMIT_RESV: | |
075a61d0 | 2842 | ret = region_add(resv, idx, idx + 1, 1, NULL, NULL); |
0db9d74e MA |
2843 | /* region_add calls of range 1 should never fail. */ |
2844 | VM_BUG_ON(ret < 0); | |
5e911373 | 2845 | break; |
feba16e2 | 2846 | case VMA_END_RESV: |
0db9d74e | 2847 | region_abort(resv, idx, idx + 1, 1); |
5e911373 MK |
2848 | ret = 0; |
2849 | break; | |
96b96a96 | 2850 | case VMA_ADD_RESV: |
0db9d74e | 2851 | if (vma->vm_flags & VM_MAYSHARE) { |
075a61d0 | 2852 | ret = region_add(resv, idx, idx + 1, 1, NULL, NULL); |
0db9d74e MA |
2853 | /* region_add calls of range 1 should never fail. */ |
2854 | VM_BUG_ON(ret < 0); | |
2855 | } else { | |
2856 | region_abort(resv, idx, idx + 1, 1); | |
96b96a96 MK |
2857 | ret = region_del(resv, idx, idx + 1); |
2858 | } | |
2859 | break; | |
846be085 MK |
2860 | case VMA_DEL_RESV: |
2861 | if (vma->vm_flags & VM_MAYSHARE) { | |
2862 | region_abort(resv, idx, idx + 1, 1); | |
2863 | ret = region_del(resv, idx, idx + 1); | |
2864 | } else { | |
2865 | ret = region_add(resv, idx, idx + 1, 1, NULL, NULL); | |
2866 | /* region_add calls of range 1 should never fail. */ | |
2867 | VM_BUG_ON(ret < 0); | |
2868 | } | |
2869 | break; | |
5e911373 MK |
2870 | default: |
2871 | BUG(); | |
2872 | } | |
84afd99b | 2873 | |
846be085 | 2874 | if (vma->vm_flags & VM_MAYSHARE || mode == VMA_DEL_RESV) |
cf3ad20b | 2875 | return ret; |
bf3d12b9 ML |
2876 | /* |
2877 | * We know private mapping must have HPAGE_RESV_OWNER set. | |
2878 | * | |
2879 | * In most cases, reserves always exist for private mappings. | |
2880 | * However, a file associated with mapping could have been | |
2881 | * hole punched or truncated after reserves were consumed. | |
2882 | * As subsequent fault on such a range will not use reserves. | |
2883 | * Subtle - The reserve map for private mappings has the | |
2884 | * opposite meaning than that of shared mappings. If NO | |
2885 | * entry is in the reserve map, it means a reservation exists. | |
2886 | * If an entry exists in the reserve map, it means the | |
2887 | * reservation has already been consumed. As a result, the | |
2888 | * return value of this routine is the opposite of the | |
2889 | * value returned from reserve map manipulation routines above. | |
2890 | */ | |
2891 | if (ret > 0) | |
2892 | return 0; | |
2893 | if (ret == 0) | |
2894 | return 1; | |
2895 | return ret; | |
c37f9fb1 | 2896 | } |
cf3ad20b MK |
2897 | |
2898 | static long vma_needs_reservation(struct hstate *h, | |
a5516438 | 2899 | struct vm_area_struct *vma, unsigned long addr) |
c37f9fb1 | 2900 | { |
5e911373 | 2901 | return __vma_reservation_common(h, vma, addr, VMA_NEEDS_RESV); |
cf3ad20b | 2902 | } |
84afd99b | 2903 | |
cf3ad20b MK |
2904 | static long vma_commit_reservation(struct hstate *h, |
2905 | struct vm_area_struct *vma, unsigned long addr) | |
2906 | { | |
5e911373 MK |
2907 | return __vma_reservation_common(h, vma, addr, VMA_COMMIT_RESV); |
2908 | } | |
2909 | ||
feba16e2 | 2910 | static void vma_end_reservation(struct hstate *h, |
5e911373 MK |
2911 | struct vm_area_struct *vma, unsigned long addr) |
2912 | { | |
feba16e2 | 2913 | (void)__vma_reservation_common(h, vma, addr, VMA_END_RESV); |
c37f9fb1 AW |
2914 | } |
2915 | ||
96b96a96 MK |
2916 | static long vma_add_reservation(struct hstate *h, |
2917 | struct vm_area_struct *vma, unsigned long addr) | |
2918 | { | |
2919 | return __vma_reservation_common(h, vma, addr, VMA_ADD_RESV); | |
2920 | } | |
2921 | ||
846be085 MK |
2922 | static long vma_del_reservation(struct hstate *h, |
2923 | struct vm_area_struct *vma, unsigned long addr) | |
2924 | { | |
2925 | return __vma_reservation_common(h, vma, addr, VMA_DEL_RESV); | |
2926 | } | |
2927 | ||
96b96a96 | 2928 | /* |
846be085 | 2929 | * This routine is called to restore reservation information on error paths. |
d0ce0e47 SK |
2930 | * It should ONLY be called for folios allocated via alloc_hugetlb_folio(), |
2931 | * and the hugetlb mutex should remain held when calling this routine. | |
846be085 MK |
2932 | * |
2933 | * It handles two specific cases: | |
d2d7bb44 SK |
2934 | * 1) A reservation was in place and the folio consumed the reservation. |
2935 | * hugetlb_restore_reserve is set in the folio. | |
2936 | * 2) No reservation was in place for the page, so hugetlb_restore_reserve is | |
d0ce0e47 | 2937 | * not set. However, alloc_hugetlb_folio always updates the reserve map. |
846be085 | 2938 | * |
454a00c4 MWO |
2939 | * In case 1, free_huge_folio later in the error path will increment the |
2940 | * global reserve count. But, free_huge_folio does not have enough context | |
846be085 MK |
2941 | * to adjust the reservation map. This case deals primarily with private |
2942 | * mappings. Adjust the reserve map here to be consistent with global | |
454a00c4 | 2943 | * reserve count adjustments to be made by free_huge_folio. Make sure the |
846be085 MK |
2944 | * reserve map indicates there is a reservation present. |
2945 | * | |
d0ce0e47 | 2946 | * In case 2, simply undo reserve map modifications done by alloc_hugetlb_folio. |
96b96a96 | 2947 | */ |
846be085 | 2948 | void restore_reserve_on_error(struct hstate *h, struct vm_area_struct *vma, |
d2d7bb44 | 2949 | unsigned long address, struct folio *folio) |
96b96a96 | 2950 | { |
846be085 | 2951 | long rc = vma_needs_reservation(h, vma, address); |
96b96a96 | 2952 | |
0ffdc38e | 2953 | if (folio_test_hugetlb_restore_reserve(folio)) { |
846be085 | 2954 | if (unlikely(rc < 0)) |
96b96a96 MK |
2955 | /* |
2956 | * Rare out of memory condition in reserve map | |
0ffdc38e SK |
2957 | * manipulation. Clear hugetlb_restore_reserve so |
2958 | * that global reserve count will not be incremented | |
454a00c4 | 2959 | * by free_huge_folio. This will make it appear |
0ffdc38e | 2960 | * as though the reservation for this folio was |
96b96a96 | 2961 | * consumed. This may prevent the task from |
0ffdc38e | 2962 | * faulting in the folio at a later time. This |
96b96a96 MK |
2963 | * is better than inconsistent global huge page |
2964 | * accounting of reserve counts. | |
2965 | */ | |
0ffdc38e | 2966 | folio_clear_hugetlb_restore_reserve(folio); |
846be085 MK |
2967 | else if (rc) |
2968 | (void)vma_add_reservation(h, vma, address); | |
2969 | else | |
2970 | vma_end_reservation(h, vma, address); | |
2971 | } else { | |
2972 | if (!rc) { | |
2973 | /* | |
2974 | * This indicates there is an entry in the reserve map | |
d0ce0e47 SK |
2975 | * not added by alloc_hugetlb_folio. We know it was added |
2976 | * before the alloc_hugetlb_folio call, otherwise | |
0ffdc38e | 2977 | * hugetlb_restore_reserve would be set on the folio. |
846be085 MK |
2978 | * Remove the entry so that a subsequent allocation |
2979 | * does not consume a reservation. | |
2980 | */ | |
2981 | rc = vma_del_reservation(h, vma, address); | |
2982 | if (rc < 0) | |
96b96a96 | 2983 | /* |
846be085 MK |
2984 | * VERY rare out of memory condition. Since |
2985 | * we can not delete the entry, set | |
0ffdc38e SK |
2986 | * hugetlb_restore_reserve so that the reserve |
2987 | * count will be incremented when the folio | |
846be085 MK |
2988 | * is freed. This reserve will be consumed |
2989 | * on a subsequent allocation. | |
96b96a96 | 2990 | */ |
0ffdc38e | 2991 | folio_set_hugetlb_restore_reserve(folio); |
846be085 MK |
2992 | } else if (rc < 0) { |
2993 | /* | |
2994 | * Rare out of memory condition from | |
2995 | * vma_needs_reservation call. Memory allocation is | |
2996 | * only attempted if a new entry is needed. Therefore, | |
2997 | * this implies there is not an entry in the | |
2998 | * reserve map. | |
2999 | * | |
3000 | * For shared mappings, no entry in the map indicates | |
3001 | * no reservation. We are done. | |
3002 | */ | |
3003 | if (!(vma->vm_flags & VM_MAYSHARE)) | |
3004 | /* | |
3005 | * For private mappings, no entry indicates | |
3006 | * a reservation is present. Since we can | |
0ffdc38e SK |
3007 | * not add an entry, set hugetlb_restore_reserve |
3008 | * on the folio so reserve count will be | |
846be085 MK |
3009 | * incremented when freed. This reserve will |
3010 | * be consumed on a subsequent allocation. | |
3011 | */ | |
0ffdc38e | 3012 | folio_set_hugetlb_restore_reserve(folio); |
96b96a96 | 3013 | } else |
846be085 MK |
3014 | /* |
3015 | * No reservation present, do nothing | |
3016 | */ | |
3017 | vma_end_reservation(h, vma, address); | |
96b96a96 MK |
3018 | } |
3019 | } | |
3020 | ||
369fa227 | 3021 | /* |
19fc1a7e SK |
3022 | * alloc_and_dissolve_hugetlb_folio - Allocate a new folio and dissolve |
3023 | * the old one | |
369fa227 | 3024 | * @h: struct hstate old page belongs to |
19fc1a7e | 3025 | * @old_folio: Old folio to dissolve |
ae37c7ff | 3026 | * @list: List to isolate the page in case we need to |
369fa227 OS |
3027 | * Returns 0 on success, otherwise negated error. |
3028 | */ | |
19fc1a7e SK |
3029 | static int alloc_and_dissolve_hugetlb_folio(struct hstate *h, |
3030 | struct folio *old_folio, struct list_head *list) | |
369fa227 OS |
3031 | { |
3032 | gfp_t gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE; | |
de656ed3 | 3033 | int nid = folio_nid(old_folio); |
831bc31a | 3034 | struct folio *new_folio = NULL; |
369fa227 OS |
3035 | int ret = 0; |
3036 | ||
369fa227 OS |
3037 | retry: |
3038 | spin_lock_irq(&hugetlb_lock); | |
de656ed3 | 3039 | if (!folio_test_hugetlb(old_folio)) { |
369fa227 | 3040 | /* |
19fc1a7e | 3041 | * Freed from under us. Drop new_folio too. |
369fa227 OS |
3042 | */ |
3043 | goto free_new; | |
de656ed3 | 3044 | } else if (folio_ref_count(old_folio)) { |
9747b9e9 BW |
3045 | bool isolated; |
3046 | ||
369fa227 | 3047 | /* |
19fc1a7e | 3048 | * Someone has grabbed the folio, try to isolate it here. |
ae37c7ff | 3049 | * Fail with -EBUSY if not possible. |
369fa227 | 3050 | */ |
ae37c7ff | 3051 | spin_unlock_irq(&hugetlb_lock); |
9747b9e9 BW |
3052 | isolated = isolate_hugetlb(old_folio, list); |
3053 | ret = isolated ? 0 : -EBUSY; | |
ae37c7ff | 3054 | spin_lock_irq(&hugetlb_lock); |
369fa227 | 3055 | goto free_new; |
de656ed3 | 3056 | } else if (!folio_test_hugetlb_freed(old_folio)) { |
369fa227 | 3057 | /* |
19fc1a7e | 3058 | * Folio's refcount is 0 but it has not been enqueued in the |
369fa227 OS |
3059 | * freelist yet. Race window is small, so we can succeed here if |
3060 | * we retry. | |
3061 | */ | |
3062 | spin_unlock_irq(&hugetlb_lock); | |
3063 | cond_resched(); | |
3064 | goto retry; | |
3065 | } else { | |
831bc31a BW |
3066 | if (!new_folio) { |
3067 | spin_unlock_irq(&hugetlb_lock); | |
3068 | new_folio = alloc_buddy_hugetlb_folio(h, gfp_mask, nid, | |
3069 | NULL, NULL); | |
3070 | if (!new_folio) | |
3071 | return -ENOMEM; | |
3072 | __prep_new_hugetlb_folio(h, new_folio); | |
3073 | goto retry; | |
3074 | } | |
3075 | ||
369fa227 | 3076 | /* |
19fc1a7e | 3077 | * Ok, old_folio is still a genuine free hugepage. Remove it from |
369fa227 OS |
3078 | * the freelist and decrease the counters. These will be |
3079 | * incremented again when calling __prep_account_new_huge_page() | |
240d67a8 SK |
3080 | * and enqueue_hugetlb_folio() for new_folio. The counters will |
3081 | * remain stable since this happens under the lock. | |
369fa227 | 3082 | */ |
cfd5082b | 3083 | remove_hugetlb_folio(h, old_folio, false); |
369fa227 OS |
3084 | |
3085 | /* | |
19fc1a7e | 3086 | * Ref count on new_folio is already zero as it was dropped |
b65a4eda | 3087 | * earlier. It can be directly added to the pool free list. |
369fa227 | 3088 | */ |
369fa227 | 3089 | __prep_account_new_huge_page(h, nid); |
240d67a8 | 3090 | enqueue_hugetlb_folio(h, new_folio); |
369fa227 OS |
3091 | |
3092 | /* | |
19fc1a7e | 3093 | * Folio has been replaced, we can safely free the old one. |
369fa227 OS |
3094 | */ |
3095 | spin_unlock_irq(&hugetlb_lock); | |
d6ef19e2 | 3096 | update_and_free_hugetlb_folio(h, old_folio, false); |
369fa227 OS |
3097 | } |
3098 | ||
3099 | return ret; | |
3100 | ||
3101 | free_new: | |
3102 | spin_unlock_irq(&hugetlb_lock); | |
831bc31a BW |
3103 | if (new_folio) { |
3104 | /* Folio has a zero ref count, but needs a ref to be freed */ | |
3105 | folio_ref_unfreeze(new_folio, 1); | |
3106 | update_and_free_hugetlb_folio(h, new_folio, false); | |
3107 | } | |
369fa227 OS |
3108 | |
3109 | return ret; | |
3110 | } | |
3111 | ||
ae37c7ff | 3112 | int isolate_or_dissolve_huge_page(struct page *page, struct list_head *list) |
369fa227 OS |
3113 | { |
3114 | struct hstate *h; | |
d5e33bd8 | 3115 | struct folio *folio = page_folio(page); |
ae37c7ff | 3116 | int ret = -EBUSY; |
369fa227 OS |
3117 | |
3118 | /* | |
3119 | * The page might have been dissolved from under our feet, so make sure | |
3120 | * to carefully check the state under the lock. | |
3121 | * Return success when racing as if we dissolved the page ourselves. | |
3122 | */ | |
3123 | spin_lock_irq(&hugetlb_lock); | |
d5e33bd8 SK |
3124 | if (folio_test_hugetlb(folio)) { |
3125 | h = folio_hstate(folio); | |
369fa227 OS |
3126 | } else { |
3127 | spin_unlock_irq(&hugetlb_lock); | |
3128 | return 0; | |
3129 | } | |
3130 | spin_unlock_irq(&hugetlb_lock); | |
3131 | ||
3132 | /* | |
3133 | * Fence off gigantic pages as there is a cyclic dependency between | |
3134 | * alloc_contig_range and them. Return -ENOMEM as this has the effect | |
3135 | * of bailing out right away without further retrying. | |
3136 | */ | |
3137 | if (hstate_is_gigantic(h)) | |
3138 | return -ENOMEM; | |
3139 | ||
9747b9e9 | 3140 | if (folio_ref_count(folio) && isolate_hugetlb(folio, list)) |
ae37c7ff | 3141 | ret = 0; |
d5e33bd8 | 3142 | else if (!folio_ref_count(folio)) |
19fc1a7e | 3143 | ret = alloc_and_dissolve_hugetlb_folio(h, folio, list); |
ae37c7ff OS |
3144 | |
3145 | return ret; | |
369fa227 OS |
3146 | } |
3147 | ||
d0ce0e47 | 3148 | struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma, |
04f2cbe3 | 3149 | unsigned long addr, int avoid_reserve) |
1da177e4 | 3150 | { |
90481622 | 3151 | struct hugepage_subpool *spool = subpool_vma(vma); |
a5516438 | 3152 | struct hstate *h = hstate_vma(vma); |
d4ab0316 | 3153 | struct folio *folio; |
8cba9576 | 3154 | long map_chg, map_commit, nr_pages = pages_per_huge_page(h); |
d85f69b0 | 3155 | long gbl_chg; |
8cba9576 | 3156 | int memcg_charge_ret, ret, idx; |
d0ce0e47 | 3157 | struct hugetlb_cgroup *h_cg = NULL; |
8cba9576 | 3158 | struct mem_cgroup *memcg; |
08cf9faf | 3159 | bool deferred_reserve; |
8cba9576 NP |
3160 | gfp_t gfp = htlb_alloc_mask(h) | __GFP_RETRY_MAYFAIL; |
3161 | ||
3162 | memcg = get_mem_cgroup_from_current(); | |
3163 | memcg_charge_ret = mem_cgroup_hugetlb_try_charge(memcg, gfp, nr_pages); | |
3164 | if (memcg_charge_ret == -ENOMEM) { | |
3165 | mem_cgroup_put(memcg); | |
3166 | return ERR_PTR(-ENOMEM); | |
3167 | } | |
a1e78772 | 3168 | |
6d76dcf4 | 3169 | idx = hstate_index(h); |
a1e78772 | 3170 | /* |
d85f69b0 MK |
3171 | * Examine the region/reserve map to determine if the process |
3172 | * has a reservation for the page to be allocated. A return | |
3173 | * code of zero indicates a reservation exists (no change). | |
a1e78772 | 3174 | */ |
d85f69b0 | 3175 | map_chg = gbl_chg = vma_needs_reservation(h, vma, addr); |
8cba9576 NP |
3176 | if (map_chg < 0) { |
3177 | if (!memcg_charge_ret) | |
3178 | mem_cgroup_cancel_charge(memcg, nr_pages); | |
3179 | mem_cgroup_put(memcg); | |
76dcee75 | 3180 | return ERR_PTR(-ENOMEM); |
8cba9576 | 3181 | } |
d85f69b0 MK |
3182 | |
3183 | /* | |
3184 | * Processes that did not create the mapping will have no | |
3185 | * reserves as indicated by the region/reserve map. Check | |
3186 | * that the allocation will not exceed the subpool limit. | |
3187 | * Allocations for MAP_NORESERVE mappings also need to be | |
3188 | * checked against any subpool limit. | |
3189 | */ | |
3190 | if (map_chg || avoid_reserve) { | |
3191 | gbl_chg = hugepage_subpool_get_pages(spool, 1); | |
8cba9576 NP |
3192 | if (gbl_chg < 0) |
3193 | goto out_end_reservation; | |
1da177e4 | 3194 | |
d85f69b0 MK |
3195 | /* |
3196 | * Even though there was no reservation in the region/reserve | |
3197 | * map, there could be reservations associated with the | |
3198 | * subpool that can be used. This would be indicated if the | |
3199 | * return value of hugepage_subpool_get_pages() is zero. | |
3200 | * However, if avoid_reserve is specified we still avoid even | |
3201 | * the subpool reservations. | |
3202 | */ | |
3203 | if (avoid_reserve) | |
3204 | gbl_chg = 1; | |
3205 | } | |
3206 | ||
08cf9faf MA |
3207 | /* If this allocation is not consuming a reservation, charge it now. |
3208 | */ | |
6501fe5f | 3209 | deferred_reserve = map_chg || avoid_reserve; |
08cf9faf MA |
3210 | if (deferred_reserve) { |
3211 | ret = hugetlb_cgroup_charge_cgroup_rsvd( | |
3212 | idx, pages_per_huge_page(h), &h_cg); | |
3213 | if (ret) | |
3214 | goto out_subpool_put; | |
3215 | } | |
3216 | ||
6d76dcf4 | 3217 | ret = hugetlb_cgroup_charge_cgroup(idx, pages_per_huge_page(h), &h_cg); |
8f34af6f | 3218 | if (ret) |
08cf9faf | 3219 | goto out_uncharge_cgroup_reservation; |
8f34af6f | 3220 | |
db71ef79 | 3221 | spin_lock_irq(&hugetlb_lock); |
d85f69b0 MK |
3222 | /* |
3223 | * glb_chg is passed to indicate whether or not a page must be taken | |
3224 | * from the global free pool (global change). gbl_chg == 0 indicates | |
3225 | * a reservation exists for the allocation. | |
3226 | */ | |
ff7d853b SK |
3227 | folio = dequeue_hugetlb_folio_vma(h, vma, addr, avoid_reserve, gbl_chg); |
3228 | if (!folio) { | |
db71ef79 | 3229 | spin_unlock_irq(&hugetlb_lock); |
ff7d853b SK |
3230 | folio = alloc_buddy_hugetlb_folio_with_mpol(h, vma, addr); |
3231 | if (!folio) | |
8f34af6f | 3232 | goto out_uncharge_cgroup; |
12df140f | 3233 | spin_lock_irq(&hugetlb_lock); |
a88c7695 | 3234 | if (!avoid_reserve && vma_has_reserves(vma, gbl_chg)) { |
ff7d853b | 3235 | folio_set_hugetlb_restore_reserve(folio); |
a88c7695 NH |
3236 | h->resv_huge_pages--; |
3237 | } | |
ff7d853b SK |
3238 | list_add(&folio->lru, &h->hugepage_activelist); |
3239 | folio_ref_unfreeze(folio, 1); | |
81a6fcae | 3240 | /* Fall through */ |
68842c9b | 3241 | } |
ff7d853b SK |
3242 | |
3243 | hugetlb_cgroup_commit_charge(idx, pages_per_huge_page(h), h_cg, folio); | |
08cf9faf MA |
3244 | /* If allocation is not consuming a reservation, also store the |
3245 | * hugetlb_cgroup pointer on the page. | |
3246 | */ | |
3247 | if (deferred_reserve) { | |
3248 | hugetlb_cgroup_commit_charge_rsvd(idx, pages_per_huge_page(h), | |
ff7d853b | 3249 | h_cg, folio); |
08cf9faf MA |
3250 | } |
3251 | ||
db71ef79 | 3252 | spin_unlock_irq(&hugetlb_lock); |
348ea204 | 3253 | |
ff7d853b | 3254 | hugetlb_set_folio_subpool(folio, spool); |
90d8b7e6 | 3255 | |
d85f69b0 MK |
3256 | map_commit = vma_commit_reservation(h, vma, addr); |
3257 | if (unlikely(map_chg > map_commit)) { | |
33039678 MK |
3258 | /* |
3259 | * The page was added to the reservation map between | |
3260 | * vma_needs_reservation and vma_commit_reservation. | |
3261 | * This indicates a race with hugetlb_reserve_pages. | |
3262 | * Adjust for the subpool count incremented above AND | |
3263 | * in hugetlb_reserve_pages for the same page. Also, | |
3264 | * the reservation count added in hugetlb_reserve_pages | |
3265 | * no longer applies. | |
3266 | */ | |
3267 | long rsv_adjust; | |
3268 | ||
3269 | rsv_adjust = hugepage_subpool_put_pages(spool, 1); | |
3270 | hugetlb_acct_memory(h, -rsv_adjust); | |
79aa925b | 3271 | if (deferred_reserve) |
d4ab0316 SK |
3272 | hugetlb_cgroup_uncharge_folio_rsvd(hstate_index(h), |
3273 | pages_per_huge_page(h), folio); | |
33039678 | 3274 | } |
8cba9576 NP |
3275 | |
3276 | if (!memcg_charge_ret) | |
3277 | mem_cgroup_commit_charge(folio, memcg); | |
3278 | mem_cgroup_put(memcg); | |
3279 | ||
d0ce0e47 | 3280 | return folio; |
8f34af6f JZ |
3281 | |
3282 | out_uncharge_cgroup: | |
3283 | hugetlb_cgroup_uncharge_cgroup(idx, pages_per_huge_page(h), h_cg); | |
08cf9faf MA |
3284 | out_uncharge_cgroup_reservation: |
3285 | if (deferred_reserve) | |
3286 | hugetlb_cgroup_uncharge_cgroup_rsvd(idx, pages_per_huge_page(h), | |
3287 | h_cg); | |
8f34af6f | 3288 | out_subpool_put: |
d85f69b0 | 3289 | if (map_chg || avoid_reserve) |
8f34af6f | 3290 | hugepage_subpool_put_pages(spool, 1); |
8cba9576 | 3291 | out_end_reservation: |
feba16e2 | 3292 | vma_end_reservation(h, vma, addr); |
8cba9576 NP |
3293 | if (!memcg_charge_ret) |
3294 | mem_cgroup_cancel_charge(memcg, nr_pages); | |
3295 | mem_cgroup_put(memcg); | |
8f34af6f | 3296 | return ERR_PTR(-ENOSPC); |
b45b5bd6 DG |
3297 | } |
3298 | ||
b5389086 | 3299 | int alloc_bootmem_huge_page(struct hstate *h, int nid) |
e24a1307 | 3300 | __attribute__ ((weak, alias("__alloc_bootmem_huge_page"))); |
b5389086 | 3301 | int __alloc_bootmem_huge_page(struct hstate *h, int nid) |
aa888a74 | 3302 | { |
b5389086 | 3303 | struct huge_bootmem_page *m = NULL; /* initialize for clang */ |
b78b27d0 | 3304 | int nr_nodes, node = nid; |
aa888a74 | 3305 | |
b5389086 ZY |
3306 | /* do node specific alloc */ |
3307 | if (nid != NUMA_NO_NODE) { | |
3308 | m = memblock_alloc_try_nid_raw(huge_page_size(h), huge_page_size(h), | |
3309 | 0, MEMBLOCK_ALLOC_ACCESSIBLE, nid); | |
3310 | if (!m) | |
3311 | return 0; | |
3312 | goto found; | |
3313 | } | |
3314 | /* allocate from next node when distributing huge pages */ | |
2e73ff23 | 3315 | for_each_node_mask_to_alloc(&h->next_nid_to_alloc, nr_nodes, node, &node_states[N_MEMORY]) { |
b5389086 | 3316 | m = memblock_alloc_try_nid_raw( |
8b89a116 | 3317 | huge_page_size(h), huge_page_size(h), |
97ad1087 | 3318 | 0, MEMBLOCK_ALLOC_ACCESSIBLE, node); |
b5389086 ZY |
3319 | /* |
3320 | * Use the beginning of the huge page to store the | |
3321 | * huge_bootmem_page struct (until gather_bootmem | |
3322 | * puts them into the mem_map). | |
3323 | */ | |
3324 | if (!m) | |
3325 | return 0; | |
3326 | goto found; | |
aa888a74 | 3327 | } |
aa888a74 AK |
3328 | |
3329 | found: | |
fde1c4ec UA |
3330 | |
3331 | /* | |
3332 | * Only initialize the head struct page in memmap_init_reserved_pages, | |
3333 | * rest of the struct pages will be initialized by the HugeTLB | |
3334 | * subsystem itself. | |
3335 | * The head struct page is used to get folio information by the HugeTLB | |
3336 | * subsystem like zone id and node id. | |
3337 | */ | |
3338 | memblock_reserved_mark_noinit(virt_to_phys((void *)m + PAGE_SIZE), | |
3339 | huge_page_size(h) - PAGE_SIZE); | |
aa888a74 | 3340 | /* Put them into a private list first because mem_map is not up yet */ |
330d6e48 | 3341 | INIT_LIST_HEAD(&m->list); |
b78b27d0 | 3342 | list_add(&m->list, &huge_boot_pages[node]); |
aa888a74 AK |
3343 | m->hstate = h; |
3344 | return 1; | |
3345 | } | |
3346 | ||
fde1c4ec UA |
3347 | /* Initialize [start_page:end_page_number] tail struct pages of a hugepage */ |
3348 | static void __init hugetlb_folio_init_tail_vmemmap(struct folio *folio, | |
3349 | unsigned long start_page_number, | |
3350 | unsigned long end_page_number) | |
3351 | { | |
3352 | enum zone_type zone = zone_idx(folio_zone(folio)); | |
3353 | int nid = folio_nid(folio); | |
3354 | unsigned long head_pfn = folio_pfn(folio); | |
3355 | unsigned long pfn, end_pfn = head_pfn + end_page_number; | |
3356 | int ret; | |
3357 | ||
3358 | for (pfn = head_pfn + start_page_number; pfn < end_pfn; pfn++) { | |
3359 | struct page *page = pfn_to_page(pfn); | |
3360 | ||
3361 | __init_single_page(page, pfn, zone, nid); | |
3362 | prep_compound_tail((struct page *)folio, pfn - head_pfn); | |
3363 | ret = page_ref_freeze(page, 1); | |
3364 | VM_BUG_ON(!ret); | |
3365 | } | |
3366 | } | |
3367 | ||
3368 | static void __init hugetlb_folio_init_vmemmap(struct folio *folio, | |
3369 | struct hstate *h, | |
3370 | unsigned long nr_pages) | |
3371 | { | |
3372 | int ret; | |
3373 | ||
3374 | /* Prepare folio head */ | |
3375 | __folio_clear_reserved(folio); | |
3376 | __folio_set_head(folio); | |
a48bf7b4 | 3377 | ret = folio_ref_freeze(folio, 1); |
fde1c4ec UA |
3378 | VM_BUG_ON(!ret); |
3379 | /* Initialize the necessary tail struct pages */ | |
3380 | hugetlb_folio_init_tail_vmemmap(folio, 1, nr_pages); | |
3381 | prep_compound_head((struct page *)folio, huge_page_order(h)); | |
3382 | } | |
3383 | ||
79359d6d MK |
3384 | static void __init prep_and_add_bootmem_folios(struct hstate *h, |
3385 | struct list_head *folio_list) | |
3386 | { | |
3387 | unsigned long flags; | |
3388 | struct folio *folio, *tmp_f; | |
3389 | ||
3390 | /* Send list for bulk vmemmap optimization processing */ | |
3391 | hugetlb_vmemmap_optimize_folios(h, folio_list); | |
3392 | ||
79359d6d MK |
3393 | list_for_each_entry_safe(folio, tmp_f, folio_list, lru) { |
3394 | if (!folio_test_hugetlb_vmemmap_optimized(folio)) { | |
3395 | /* | |
3396 | * If HVO fails, initialize all tail struct pages | |
3397 | * We do not worry about potential long lock hold | |
3398 | * time as this is early in boot and there should | |
3399 | * be no contention. | |
3400 | */ | |
3401 | hugetlb_folio_init_tail_vmemmap(folio, | |
3402 | HUGETLB_VMEMMAP_RESERVE_PAGES, | |
3403 | pages_per_huge_page(h)); | |
3404 | } | |
b78b27d0 GL |
3405 | /* Subdivide locks to achieve better parallel performance */ |
3406 | spin_lock_irqsave(&hugetlb_lock, flags); | |
79359d6d MK |
3407 | __prep_account_new_huge_page(h, folio_nid(folio)); |
3408 | enqueue_hugetlb_folio(h, folio); | |
b78b27d0 | 3409 | spin_unlock_irqrestore(&hugetlb_lock, flags); |
79359d6d | 3410 | } |
79359d6d MK |
3411 | } |
3412 | ||
48b8d744 MK |
3413 | /* |
3414 | * Put bootmem huge pages into the standard lists after mem_map is up. | |
5e0a760b | 3415 | * Note: This only applies to gigantic (order > MAX_PAGE_ORDER) pages. |
48b8d744 | 3416 | */ |
b78b27d0 | 3417 | static void __init gather_bootmem_prealloc_node(unsigned long nid) |
aa888a74 | 3418 | { |
d67e32f2 | 3419 | LIST_HEAD(folio_list); |
aa888a74 | 3420 | struct huge_bootmem_page *m; |
d67e32f2 | 3421 | struct hstate *h = NULL, *prev_h = NULL; |
aa888a74 | 3422 | |
b78b27d0 | 3423 | list_for_each_entry(m, &huge_boot_pages[nid], list) { |
40d18ebf | 3424 | struct page *page = virt_to_page(m); |
fde1c4ec | 3425 | struct folio *folio = (void *)page; |
d67e32f2 MK |
3426 | |
3427 | h = m->hstate; | |
3428 | /* | |
3429 | * It is possible to have multiple huge page sizes (hstates) | |
3430 | * in this list. If so, process each size separately. | |
3431 | */ | |
3432 | if (h != prev_h && prev_h != NULL) | |
79359d6d | 3433 | prep_and_add_bootmem_folios(prev_h, &folio_list); |
d67e32f2 | 3434 | prev_h = h; |
ee8f248d | 3435 | |
48b8d744 | 3436 | VM_BUG_ON(!hstate_is_gigantic(h)); |
d1c60955 | 3437 | WARN_ON(folio_ref_count(folio) != 1); |
fde1c4ec UA |
3438 | |
3439 | hugetlb_folio_init_vmemmap(folio, h, | |
3440 | HUGETLB_VMEMMAP_RESERVE_PAGES); | |
79359d6d | 3441 | init_new_hugetlb_folio(h, folio); |
d67e32f2 | 3442 | list_add(&folio->lru, &folio_list); |
af0fb9df | 3443 | |
b0320c7b | 3444 | /* |
48b8d744 MK |
3445 | * We need to restore the 'stolen' pages to totalram_pages |
3446 | * in order to fix confusing memory reports from free(1) and | |
3447 | * other side-effects, like CommitLimit going negative. | |
b0320c7b | 3448 | */ |
48b8d744 | 3449 | adjust_managed_page_count(page, pages_per_huge_page(h)); |
520495fe | 3450 | cond_resched(); |
aa888a74 | 3451 | } |
d67e32f2 | 3452 | |
79359d6d | 3453 | prep_and_add_bootmem_folios(h, &folio_list); |
aa888a74 | 3454 | } |
fde1c4ec | 3455 | |
b78b27d0 GL |
3456 | static void __init gather_bootmem_prealloc_parallel(unsigned long start, |
3457 | unsigned long end, void *arg) | |
3458 | { | |
3459 | int nid; | |
3460 | ||
3461 | for (nid = start; nid < end; nid++) | |
3462 | gather_bootmem_prealloc_node(nid); | |
3463 | } | |
3464 | ||
3465 | static void __init gather_bootmem_prealloc(void) | |
3466 | { | |
3467 | struct padata_mt_job job = { | |
3468 | .thread_fn = gather_bootmem_prealloc_parallel, | |
3469 | .fn_arg = NULL, | |
3470 | .start = 0, | |
3471 | .size = num_node_state(N_MEMORY), | |
3472 | .align = 1, | |
3473 | .min_chunk = 1, | |
3474 | .max_threads = num_node_state(N_MEMORY), | |
3475 | .numa_aware = true, | |
3476 | }; | |
3477 | ||
3478 | padata_do_multithreaded(&job); | |
3479 | } | |
3480 | ||
b5389086 ZY |
3481 | static void __init hugetlb_hstate_alloc_pages_onenode(struct hstate *h, int nid) |
3482 | { | |
3483 | unsigned long i; | |
3484 | char buf[32]; | |
3485 | ||
3486 | for (i = 0; i < h->max_huge_pages_node[nid]; ++i) { | |
3487 | if (hstate_is_gigantic(h)) { | |
3488 | if (!alloc_bootmem_huge_page(h, nid)) | |
3489 | break; | |
3490 | } else { | |
19fc1a7e | 3491 | struct folio *folio; |
b5389086 ZY |
3492 | gfp_t gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE; |
3493 | ||
19fc1a7e | 3494 | folio = alloc_fresh_hugetlb_folio(h, gfp_mask, nid, |
b5389086 | 3495 | &node_states[N_MEMORY], NULL); |
19fc1a7e | 3496 | if (!folio) |
b5389086 | 3497 | break; |
454a00c4 | 3498 | free_huge_folio(folio); /* free it into the hugepage allocator */ |
b5389086 ZY |
3499 | } |
3500 | cond_resched(); | |
3501 | } | |
3502 | if (i == h->max_huge_pages_node[nid]) | |
3503 | return; | |
3504 | ||
3505 | string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32); | |
3506 | pr_warn("HugeTLB: allocating %u of page size %s failed node%d. Only allocated %lu hugepages.\n", | |
3507 | h->max_huge_pages_node[nid], buf, nid, i); | |
3508 | h->max_huge_pages -= (h->max_huge_pages_node[nid] - i); | |
3509 | h->max_huge_pages_node[nid] = i; | |
3510 | } | |
aa888a74 | 3511 | |
fc37bbb3 GL |
3512 | static bool __init hugetlb_hstate_alloc_pages_specific_nodes(struct hstate *h) |
3513 | { | |
3514 | int i; | |
3515 | bool node_specific_alloc = false; | |
3516 | ||
3517 | for_each_online_node(i) { | |
3518 | if (h->max_huge_pages_node[i] > 0) { | |
3519 | hugetlb_hstate_alloc_pages_onenode(h, i); | |
3520 | node_specific_alloc = true; | |
3521 | } | |
3522 | } | |
3523 | ||
3524 | return node_specific_alloc; | |
3525 | } | |
3526 | ||
3527 | static void __init hugetlb_hstate_alloc_pages_errcheck(unsigned long allocated, struct hstate *h) | |
3528 | { | |
3529 | if (allocated < h->max_huge_pages) { | |
3530 | char buf[32]; | |
3531 | ||
3532 | string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32); | |
3533 | pr_warn("HugeTLB: allocating %lu of page size %s failed. Only allocated %lu hugepages.\n", | |
3534 | h->max_huge_pages, buf, allocated); | |
3535 | h->max_huge_pages = allocated; | |
3536 | } | |
3537 | } | |
3538 | ||
c6c21c31 GL |
3539 | static void __init hugetlb_pages_alloc_boot_node(unsigned long start, unsigned long end, void *arg) |
3540 | { | |
3541 | struct hstate *h = (struct hstate *)arg; | |
3542 | int i, num = end - start; | |
3543 | nodemask_t node_alloc_noretry; | |
3544 | LIST_HEAD(folio_list); | |
3545 | int next_node = first_online_node; | |
3546 | ||
3547 | /* Bit mask controlling how hard we retry per-node allocations.*/ | |
3548 | nodes_clear(node_alloc_noretry); | |
3549 | ||
3550 | for (i = 0; i < num; ++i) { | |
3551 | struct folio *folio = alloc_pool_huge_folio(h, &node_states[N_MEMORY], | |
3552 | &node_alloc_noretry, &next_node); | |
3553 | if (!folio) | |
3554 | break; | |
3555 | ||
3556 | list_move(&folio->lru, &folio_list); | |
3557 | cond_resched(); | |
3558 | } | |
3559 | ||
3560 | prep_and_add_allocated_folios(h, &folio_list); | |
3561 | } | |
3562 | ||
d5c3eb3f GL |
3563 | static unsigned long __init hugetlb_gigantic_pages_alloc_boot(struct hstate *h) |
3564 | { | |
3565 | unsigned long i; | |
3566 | ||
3567 | for (i = 0; i < h->max_huge_pages; ++i) { | |
3568 | if (!alloc_bootmem_huge_page(h, NUMA_NO_NODE)) | |
3569 | break; | |
3570 | cond_resched(); | |
3571 | } | |
3572 | ||
3573 | return i; | |
3574 | } | |
3575 | ||
3576 | static unsigned long __init hugetlb_pages_alloc_boot(struct hstate *h) | |
3577 | { | |
c6c21c31 GL |
3578 | struct padata_mt_job job = { |
3579 | .fn_arg = h, | |
3580 | .align = 1, | |
3581 | .numa_aware = true | |
3582 | }; | |
d5c3eb3f | 3583 | |
c6c21c31 GL |
3584 | job.thread_fn = hugetlb_pages_alloc_boot_node; |
3585 | job.start = 0; | |
3586 | job.size = h->max_huge_pages; | |
d5c3eb3f | 3587 | |
c6c21c31 GL |
3588 | /* |
3589 | * job.max_threads is twice the num_node_state(N_MEMORY), | |
3590 | * | |
3591 | * Tests below indicate that a multiplier of 2 significantly improves | |
3592 | * performance, and although larger values also provide improvements, | |
3593 | * the gains are marginal. | |
3594 | * | |
3595 | * Therefore, choosing 2 as the multiplier strikes a good balance between | |
3596 | * enhancing parallel processing capabilities and maintaining efficient | |
3597 | * resource management. | |
3598 | * | |
3599 | * +------------+-------+-------+-------+-------+-------+ | |
3600 | * | multiplier | 1 | 2 | 3 | 4 | 5 | | |
3601 | * +------------+-------+-------+-------+-------+-------+ | |
3602 | * | 256G 2node | 358ms | 215ms | 157ms | 134ms | 126ms | | |
3603 | * | 2T 4node | 979ms | 679ms | 543ms | 489ms | 481ms | | |
3604 | * | 50G 2node | 71ms | 44ms | 37ms | 30ms | 31ms | | |
3605 | * +------------+-------+-------+-------+-------+-------+ | |
3606 | */ | |
3607 | job.max_threads = num_node_state(N_MEMORY) * 2; | |
3608 | job.min_chunk = h->max_huge_pages / num_node_state(N_MEMORY) / 2; | |
3609 | padata_do_multithreaded(&job); | |
d5c3eb3f | 3610 | |
c6c21c31 | 3611 | return h->nr_huge_pages; |
d5c3eb3f GL |
3612 | } |
3613 | ||
d67e32f2 MK |
3614 | /* |
3615 | * NOTE: this routine is called in different contexts for gigantic and | |
3616 | * non-gigantic pages. | |
3617 | * - For gigantic pages, this is called early in the boot process and | |
3618 | * pages are allocated from memblock allocated or something similar. | |
3619 | * Gigantic pages are actually added to pools later with the routine | |
3620 | * gather_bootmem_prealloc. | |
3621 | * - For non-gigantic pages, this is called later in the boot process after | |
3622 | * all of mm is up and functional. Pages are allocated from buddy and | |
3623 | * then added to hugetlb pools. | |
3624 | */ | |
8faa8b07 | 3625 | static void __init hugetlb_hstate_alloc_pages(struct hstate *h) |
1da177e4 | 3626 | { |
d5c3eb3f | 3627 | unsigned long allocated; |
b78b27d0 | 3628 | static bool initialized __initdata; |
b5389086 ZY |
3629 | |
3630 | /* skip gigantic hugepages allocation if hugetlb_cma enabled */ | |
3631 | if (hstate_is_gigantic(h) && hugetlb_cma_size) { | |
3632 | pr_warn_once("HugeTLB: hugetlb_cma is enabled, skip boot time allocation\n"); | |
3633 | return; | |
3634 | } | |
3635 | ||
b78b27d0 GL |
3636 | /* hugetlb_hstate_alloc_pages will be called many times, initialize huge_boot_pages once */ |
3637 | if (!initialized) { | |
3638 | int i = 0; | |
3639 | ||
3640 | for (i = 0; i < MAX_NUMNODES; i++) | |
3641 | INIT_LIST_HEAD(&huge_boot_pages[i]); | |
3642 | initialized = true; | |
3643 | } | |
3644 | ||
b5389086 | 3645 | /* do node specific alloc */ |
fc37bbb3 | 3646 | if (hugetlb_hstate_alloc_pages_specific_nodes(h)) |
b5389086 ZY |
3647 | return; |
3648 | ||
3649 | /* below will do all node balanced alloc */ | |
d5c3eb3f GL |
3650 | if (hstate_is_gigantic(h)) |
3651 | allocated = hugetlb_gigantic_pages_alloc_boot(h); | |
3652 | else | |
3653 | allocated = hugetlb_pages_alloc_boot(h); | |
d67e32f2 | 3654 | |
d5c3eb3f | 3655 | hugetlb_hstate_alloc_pages_errcheck(allocated, h); |
e5ff2159 AK |
3656 | } |
3657 | ||
3658 | static void __init hugetlb_init_hstates(void) | |
3659 | { | |
79dfc695 | 3660 | struct hstate *h, *h2; |
e5ff2159 AK |
3661 | |
3662 | for_each_hstate(h) { | |
8faa8b07 | 3663 | /* oversize hugepages were init'ed in early boot */ |
bae7f4ae | 3664 | if (!hstate_is_gigantic(h)) |
8faa8b07 | 3665 | hugetlb_hstate_alloc_pages(h); |
79dfc695 MK |
3666 | |
3667 | /* | |
3668 | * Set demote order for each hstate. Note that | |
3669 | * h->demote_order is initially 0. | |
3670 | * - We can not demote gigantic pages if runtime freeing | |
3671 | * is not supported, so skip this. | |
a01f4390 MK |
3672 | * - If CMA allocation is possible, we can not demote |
3673 | * HUGETLB_PAGE_ORDER or smaller size pages. | |
79dfc695 MK |
3674 | */ |
3675 | if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) | |
3676 | continue; | |
a01f4390 MK |
3677 | if (hugetlb_cma_size && h->order <= HUGETLB_PAGE_ORDER) |
3678 | continue; | |
79dfc695 MK |
3679 | for_each_hstate(h2) { |
3680 | if (h2 == h) | |
3681 | continue; | |
3682 | if (h2->order < h->order && | |
3683 | h2->order > h->demote_order) | |
3684 | h->demote_order = h2->order; | |
3685 | } | |
e5ff2159 AK |
3686 | } |
3687 | } | |
3688 | ||
3689 | static void __init report_hugepages(void) | |
3690 | { | |
3691 | struct hstate *h; | |
3692 | ||
3693 | for_each_hstate(h) { | |
4abd32db | 3694 | char buf[32]; |
c6247f72 MW |
3695 | |
3696 | string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32); | |
6213834c | 3697 | pr_info("HugeTLB: registered %s page size, pre-allocated %ld pages\n", |
c6247f72 | 3698 | buf, h->free_huge_pages); |
6213834c MS |
3699 | pr_info("HugeTLB: %d KiB vmemmap can be freed for a %s page\n", |
3700 | hugetlb_vmemmap_optimizable_size(h) / SZ_1K, buf); | |
e5ff2159 AK |
3701 | } |
3702 | } | |
3703 | ||
1da177e4 | 3704 | #ifdef CONFIG_HIGHMEM |
6ae11b27 LS |
3705 | static void try_to_free_low(struct hstate *h, unsigned long count, |
3706 | nodemask_t *nodes_allowed) | |
1da177e4 | 3707 | { |
4415cc8d | 3708 | int i; |
1121828a | 3709 | LIST_HEAD(page_list); |
4415cc8d | 3710 | |
9487ca60 | 3711 | lockdep_assert_held(&hugetlb_lock); |
bae7f4ae | 3712 | if (hstate_is_gigantic(h)) |
aa888a74 AK |
3713 | return; |
3714 | ||
1121828a MK |
3715 | /* |
3716 | * Collect pages to be freed on a list, and free after dropping lock | |
3717 | */ | |
6ae11b27 | 3718 | for_each_node_mask(i, *nodes_allowed) { |
04bbfd84 | 3719 | struct folio *folio, *next; |
a5516438 | 3720 | struct list_head *freel = &h->hugepage_freelists[i]; |
04bbfd84 | 3721 | list_for_each_entry_safe(folio, next, freel, lru) { |
a5516438 | 3722 | if (count >= h->nr_huge_pages) |
1121828a | 3723 | goto out; |
04bbfd84 | 3724 | if (folio_test_highmem(folio)) |
1da177e4 | 3725 | continue; |
04bbfd84 MWO |
3726 | remove_hugetlb_folio(h, folio, false); |
3727 | list_add(&folio->lru, &page_list); | |
1da177e4 LT |
3728 | } |
3729 | } | |
1121828a MK |
3730 | |
3731 | out: | |
db71ef79 | 3732 | spin_unlock_irq(&hugetlb_lock); |
10c6ec49 | 3733 | update_and_free_pages_bulk(h, &page_list); |
db71ef79 | 3734 | spin_lock_irq(&hugetlb_lock); |
1da177e4 LT |
3735 | } |
3736 | #else | |
6ae11b27 LS |
3737 | static inline void try_to_free_low(struct hstate *h, unsigned long count, |
3738 | nodemask_t *nodes_allowed) | |
1da177e4 LT |
3739 | { |
3740 | } | |
3741 | #endif | |
3742 | ||
20a0307c WF |
3743 | /* |
3744 | * Increment or decrement surplus_huge_pages. Keep node-specific counters | |
3745 | * balanced by operating on them in a round-robin fashion. | |
3746 | * Returns 1 if an adjustment was made. | |
3747 | */ | |
6ae11b27 LS |
3748 | static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed, |
3749 | int delta) | |
20a0307c | 3750 | { |
b2261026 | 3751 | int nr_nodes, node; |
20a0307c | 3752 | |
9487ca60 | 3753 | lockdep_assert_held(&hugetlb_lock); |
20a0307c | 3754 | VM_BUG_ON(delta != -1 && delta != 1); |
20a0307c | 3755 | |
b2261026 | 3756 | if (delta < 0) { |
2e73ff23 | 3757 | for_each_node_mask_to_alloc(&h->next_nid_to_alloc, nr_nodes, node, nodes_allowed) { |
b2261026 JK |
3758 | if (h->surplus_huge_pages_node[node]) |
3759 | goto found; | |
e8c5c824 | 3760 | } |
b2261026 JK |
3761 | } else { |
3762 | for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { | |
3763 | if (h->surplus_huge_pages_node[node] < | |
3764 | h->nr_huge_pages_node[node]) | |
3765 | goto found; | |
e8c5c824 | 3766 | } |
b2261026 JK |
3767 | } |
3768 | return 0; | |
20a0307c | 3769 | |
b2261026 JK |
3770 | found: |
3771 | h->surplus_huge_pages += delta; | |
3772 | h->surplus_huge_pages_node[node] += delta; | |
3773 | return 1; | |
20a0307c WF |
3774 | } |
3775 | ||
a5516438 | 3776 | #define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages) |
fd875dca | 3777 | static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid, |
4eb0716e | 3778 | nodemask_t *nodes_allowed) |
1da177e4 | 3779 | { |
d67e32f2 MK |
3780 | unsigned long min_count; |
3781 | unsigned long allocated; | |
3782 | struct folio *folio; | |
10c6ec49 | 3783 | LIST_HEAD(page_list); |
f60858f9 MK |
3784 | NODEMASK_ALLOC(nodemask_t, node_alloc_noretry, GFP_KERNEL); |
3785 | ||
3786 | /* | |
3787 | * Bit mask controlling how hard we retry per-node allocations. | |
3788 | * If we can not allocate the bit mask, do not attempt to allocate | |
3789 | * the requested huge pages. | |
3790 | */ | |
3791 | if (node_alloc_noretry) | |
3792 | nodes_clear(*node_alloc_noretry); | |
3793 | else | |
3794 | return -ENOMEM; | |
1da177e4 | 3795 | |
29383967 MK |
3796 | /* |
3797 | * resize_lock mutex prevents concurrent adjustments to number of | |
3798 | * pages in hstate via the proc/sysfs interfaces. | |
3799 | */ | |
3800 | mutex_lock(&h->resize_lock); | |
b65d4adb | 3801 | flush_free_hpage_work(h); |
db71ef79 | 3802 | spin_lock_irq(&hugetlb_lock); |
4eb0716e | 3803 | |
fd875dca MK |
3804 | /* |
3805 | * Check for a node specific request. | |
3806 | * Changing node specific huge page count may require a corresponding | |
3807 | * change to the global count. In any case, the passed node mask | |
3808 | * (nodes_allowed) will restrict alloc/free to the specified node. | |
3809 | */ | |
3810 | if (nid != NUMA_NO_NODE) { | |
3811 | unsigned long old_count = count; | |
3812 | ||
b72b3c9c XH |
3813 | count += persistent_huge_pages(h) - |
3814 | (h->nr_huge_pages_node[nid] - | |
3815 | h->surplus_huge_pages_node[nid]); | |
fd875dca MK |
3816 | /* |
3817 | * User may have specified a large count value which caused the | |
3818 | * above calculation to overflow. In this case, they wanted | |
3819 | * to allocate as many huge pages as possible. Set count to | |
3820 | * largest possible value to align with their intention. | |
3821 | */ | |
3822 | if (count < old_count) | |
3823 | count = ULONG_MAX; | |
3824 | } | |
3825 | ||
4eb0716e AG |
3826 | /* |
3827 | * Gigantic pages runtime allocation depend on the capability for large | |
3828 | * page range allocation. | |
3829 | * If the system does not provide this feature, return an error when | |
3830 | * the user tries to allocate gigantic pages but let the user free the | |
3831 | * boottime allocated gigantic pages. | |
3832 | */ | |
3833 | if (hstate_is_gigantic(h) && !IS_ENABLED(CONFIG_CONTIG_ALLOC)) { | |
3834 | if (count > persistent_huge_pages(h)) { | |
db71ef79 | 3835 | spin_unlock_irq(&hugetlb_lock); |
29383967 | 3836 | mutex_unlock(&h->resize_lock); |
f60858f9 | 3837 | NODEMASK_FREE(node_alloc_noretry); |
4eb0716e AG |
3838 | return -EINVAL; |
3839 | } | |
3840 | /* Fall through to decrease pool */ | |
3841 | } | |
aa888a74 | 3842 | |
7893d1d5 AL |
3843 | /* |
3844 | * Increase the pool size | |
3845 | * First take pages out of surplus state. Then make up the | |
3846 | * remaining difference by allocating fresh huge pages. | |
d1c3fb1f | 3847 | * |
3a740e8b | 3848 | * We might race with alloc_surplus_hugetlb_folio() here and be unable |
d1c3fb1f NA |
3849 | * to convert a surplus huge page to a normal huge page. That is |
3850 | * not critical, though, it just means the overall size of the | |
3851 | * pool might be one hugepage larger than it needs to be, but | |
3852 | * within all the constraints specified by the sysctls. | |
7893d1d5 | 3853 | */ |
a5516438 | 3854 | while (h->surplus_huge_pages && count > persistent_huge_pages(h)) { |
6ae11b27 | 3855 | if (!adjust_pool_surplus(h, nodes_allowed, -1)) |
7893d1d5 AL |
3856 | break; |
3857 | } | |
3858 | ||
d67e32f2 MK |
3859 | allocated = 0; |
3860 | while (count > (persistent_huge_pages(h) + allocated)) { | |
7893d1d5 AL |
3861 | /* |
3862 | * If this allocation races such that we no longer need the | |
454a00c4 | 3863 | * page, free_huge_folio will handle it by freeing the page |
7893d1d5 AL |
3864 | * and reducing the surplus. |
3865 | */ | |
db71ef79 | 3866 | spin_unlock_irq(&hugetlb_lock); |
649920c6 JH |
3867 | |
3868 | /* yield cpu to avoid soft lockup */ | |
3869 | cond_resched(); | |
3870 | ||
d67e32f2 | 3871 | folio = alloc_pool_huge_folio(h, nodes_allowed, |
2e73ff23 GL |
3872 | node_alloc_noretry, |
3873 | &h->next_nid_to_alloc); | |
d67e32f2 MK |
3874 | if (!folio) { |
3875 | prep_and_add_allocated_folios(h, &page_list); | |
3876 | spin_lock_irq(&hugetlb_lock); | |
7893d1d5 | 3877 | goto out; |
d67e32f2 MK |
3878 | } |
3879 | ||
3880 | list_add(&folio->lru, &page_list); | |
3881 | allocated++; | |
7893d1d5 | 3882 | |
536240f2 | 3883 | /* Bail for signals. Probably ctrl-c from user */ |
d67e32f2 MK |
3884 | if (signal_pending(current)) { |
3885 | prep_and_add_allocated_folios(h, &page_list); | |
3886 | spin_lock_irq(&hugetlb_lock); | |
536240f2 | 3887 | goto out; |
d67e32f2 MK |
3888 | } |
3889 | ||
3890 | spin_lock_irq(&hugetlb_lock); | |
3891 | } | |
3892 | ||
3893 | /* Add allocated pages to the pool */ | |
3894 | if (!list_empty(&page_list)) { | |
3895 | spin_unlock_irq(&hugetlb_lock); | |
3896 | prep_and_add_allocated_folios(h, &page_list); | |
3897 | spin_lock_irq(&hugetlb_lock); | |
7893d1d5 | 3898 | } |
7893d1d5 AL |
3899 | |
3900 | /* | |
3901 | * Decrease the pool size | |
3902 | * First return free pages to the buddy allocator (being careful | |
3903 | * to keep enough around to satisfy reservations). Then place | |
3904 | * pages into surplus state as needed so the pool will shrink | |
3905 | * to the desired size as pages become free. | |
d1c3fb1f NA |
3906 | * |
3907 | * By placing pages into the surplus state independent of the | |
3908 | * overcommit value, we are allowing the surplus pool size to | |
3909 | * exceed overcommit. There are few sane options here. Since | |
3a740e8b | 3910 | * alloc_surplus_hugetlb_folio() is checking the global counter, |
d1c3fb1f NA |
3911 | * though, we'll note that we're not allowed to exceed surplus |
3912 | * and won't grow the pool anywhere else. Not until one of the | |
3913 | * sysctls are changed, or the surplus pages go out of use. | |
7893d1d5 | 3914 | */ |
a5516438 | 3915 | min_count = h->resv_huge_pages + h->nr_huge_pages - h->free_huge_pages; |
6b0c880d | 3916 | min_count = max(count, min_count); |
6ae11b27 | 3917 | try_to_free_low(h, min_count, nodes_allowed); |
10c6ec49 MK |
3918 | |
3919 | /* | |
3920 | * Collect pages to be removed on list without dropping lock | |
3921 | */ | |
a5516438 | 3922 | while (min_count < persistent_huge_pages(h)) { |
d5b43e96 MWO |
3923 | folio = remove_pool_hugetlb_folio(h, nodes_allowed, 0); |
3924 | if (!folio) | |
1da177e4 | 3925 | break; |
10c6ec49 | 3926 | |
d5b43e96 | 3927 | list_add(&folio->lru, &page_list); |
1da177e4 | 3928 | } |
10c6ec49 | 3929 | /* free the pages after dropping lock */ |
db71ef79 | 3930 | spin_unlock_irq(&hugetlb_lock); |
10c6ec49 | 3931 | update_and_free_pages_bulk(h, &page_list); |
b65d4adb | 3932 | flush_free_hpage_work(h); |
db71ef79 | 3933 | spin_lock_irq(&hugetlb_lock); |
10c6ec49 | 3934 | |
a5516438 | 3935 | while (count < persistent_huge_pages(h)) { |
6ae11b27 | 3936 | if (!adjust_pool_surplus(h, nodes_allowed, 1)) |
7893d1d5 AL |
3937 | break; |
3938 | } | |
3939 | out: | |
4eb0716e | 3940 | h->max_huge_pages = persistent_huge_pages(h); |
db71ef79 | 3941 | spin_unlock_irq(&hugetlb_lock); |
29383967 | 3942 | mutex_unlock(&h->resize_lock); |
4eb0716e | 3943 | |
f60858f9 MK |
3944 | NODEMASK_FREE(node_alloc_noretry); |
3945 | ||
4eb0716e | 3946 | return 0; |
1da177e4 LT |
3947 | } |
3948 | ||
bdd7be07 | 3949 | static int demote_free_hugetlb_folio(struct hstate *h, struct folio *folio) |
8531fc6f | 3950 | { |
bdd7be07 | 3951 | int i, nid = folio_nid(folio); |
8531fc6f | 3952 | struct hstate *target_hstate; |
31731452 | 3953 | struct page *subpage; |
bdd7be07 | 3954 | struct folio *inner_folio; |
8531fc6f MK |
3955 | int rc = 0; |
3956 | ||
3957 | target_hstate = size_to_hstate(PAGE_SIZE << h->demote_order); | |
3958 | ||
cfd5082b | 3959 | remove_hugetlb_folio_for_demote(h, folio, false); |
8531fc6f MK |
3960 | spin_unlock_irq(&hugetlb_lock); |
3961 | ||
d8f5f7e4 MK |
3962 | /* |
3963 | * If vmemmap already existed for folio, the remove routine above would | |
3964 | * have cleared the hugetlb folio flag. Hence the folio is technically | |
c5ad3233 | 3965 | * no longer a hugetlb folio. hugetlb_vmemmap_restore_folio can only be |
d8f5f7e4 MK |
3966 | * passed hugetlb folios and will BUG otherwise. |
3967 | */ | |
3968 | if (folio_test_hugetlb(folio)) { | |
c5ad3233 | 3969 | rc = hugetlb_vmemmap_restore_folio(h, folio); |
d8f5f7e4 MK |
3970 | if (rc) { |
3971 | /* Allocation of vmemmmap failed, we can not demote folio */ | |
3972 | spin_lock_irq(&hugetlb_lock); | |
3973 | folio_ref_unfreeze(folio, 1); | |
3974 | add_hugetlb_folio(h, folio, false); | |
3975 | return rc; | |
3976 | } | |
8531fc6f MK |
3977 | } |
3978 | ||
3979 | /* | |
911565b8 | 3980 | * Use destroy_compound_hugetlb_folio_for_demote for all huge page |
bdd7be07 | 3981 | * sizes as it will not ref count folios. |
8531fc6f | 3982 | */ |
911565b8 | 3983 | destroy_compound_hugetlb_folio_for_demote(folio, huge_page_order(h)); |
8531fc6f MK |
3984 | |
3985 | /* | |
3986 | * Taking target hstate mutex synchronizes with set_max_huge_pages. | |
3987 | * Without the mutex, pages added to target hstate could be marked | |
3988 | * as surplus. | |
3989 | * | |
3990 | * Note that we already hold h->resize_lock. To prevent deadlock, | |
3991 | * use the convention of always taking larger size hstate mutex first. | |
3992 | */ | |
3993 | mutex_lock(&target_hstate->resize_lock); | |
3994 | for (i = 0; i < pages_per_huge_page(h); | |
3995 | i += pages_per_huge_page(target_hstate)) { | |
bdd7be07 SK |
3996 | subpage = folio_page(folio, i); |
3997 | inner_folio = page_folio(subpage); | |
8531fc6f | 3998 | if (hstate_is_gigantic(target_hstate)) |
bdd7be07 | 3999 | prep_compound_gigantic_folio_for_demote(inner_folio, |
8531fc6f MK |
4000 | target_hstate->order); |
4001 | else | |
31731452 | 4002 | prep_compound_page(subpage, target_hstate->order); |
bdd7be07 SK |
4003 | folio_change_private(inner_folio, NULL); |
4004 | prep_new_hugetlb_folio(target_hstate, inner_folio, nid); | |
454a00c4 | 4005 | free_huge_folio(inner_folio); |
8531fc6f MK |
4006 | } |
4007 | mutex_unlock(&target_hstate->resize_lock); | |
4008 | ||
4009 | spin_lock_irq(&hugetlb_lock); | |
4010 | ||
4011 | /* | |
4012 | * Not absolutely necessary, but for consistency update max_huge_pages | |
4013 | * based on pool changes for the demoted page. | |
4014 | */ | |
4015 | h->max_huge_pages--; | |
a43a83c7 ML |
4016 | target_hstate->max_huge_pages += |
4017 | pages_per_huge_page(h) / pages_per_huge_page(target_hstate); | |
8531fc6f MK |
4018 | |
4019 | return rc; | |
4020 | } | |
4021 | ||
79dfc695 MK |
4022 | static int demote_pool_huge_page(struct hstate *h, nodemask_t *nodes_allowed) |
4023 | __must_hold(&hugetlb_lock) | |
4024 | { | |
8531fc6f | 4025 | int nr_nodes, node; |
bdd7be07 | 4026 | struct folio *folio; |
79dfc695 MK |
4027 | |
4028 | lockdep_assert_held(&hugetlb_lock); | |
4029 | ||
4030 | /* We should never get here if no demote order */ | |
4031 | if (!h->demote_order) { | |
4032 | pr_warn("HugeTLB: NULL demote order passed to demote_pool_huge_page.\n"); | |
4033 | return -EINVAL; /* internal error */ | |
4034 | } | |
4035 | ||
8531fc6f | 4036 | for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { |
bdd7be07 SK |
4037 | list_for_each_entry(folio, &h->hugepage_freelists[node], lru) { |
4038 | if (folio_test_hwpoison(folio)) | |
5a317412 | 4039 | continue; |
bdd7be07 | 4040 | return demote_free_hugetlb_folio(h, folio); |
8531fc6f MK |
4041 | } |
4042 | } | |
4043 | ||
5a317412 MK |
4044 | /* |
4045 | * Only way to get here is if all pages on free lists are poisoned. | |
4046 | * Return -EBUSY so that caller will not retry. | |
4047 | */ | |
4048 | return -EBUSY; | |
79dfc695 MK |
4049 | } |
4050 | ||
a3437870 NA |
4051 | #define HSTATE_ATTR_RO(_name) \ |
4052 | static struct kobj_attribute _name##_attr = __ATTR_RO(_name) | |
4053 | ||
79dfc695 MK |
4054 | #define HSTATE_ATTR_WO(_name) \ |
4055 | static struct kobj_attribute _name##_attr = __ATTR_WO(_name) | |
4056 | ||
a3437870 | 4057 | #define HSTATE_ATTR(_name) \ |
98bc26ac | 4058 | static struct kobj_attribute _name##_attr = __ATTR_RW(_name) |
a3437870 NA |
4059 | |
4060 | static struct kobject *hugepages_kobj; | |
4061 | static struct kobject *hstate_kobjs[HUGE_MAX_HSTATE]; | |
4062 | ||
9a305230 LS |
4063 | static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp); |
4064 | ||
4065 | static struct hstate *kobj_to_hstate(struct kobject *kobj, int *nidp) | |
a3437870 NA |
4066 | { |
4067 | int i; | |
9a305230 | 4068 | |
a3437870 | 4069 | for (i = 0; i < HUGE_MAX_HSTATE; i++) |
9a305230 LS |
4070 | if (hstate_kobjs[i] == kobj) { |
4071 | if (nidp) | |
4072 | *nidp = NUMA_NO_NODE; | |
a3437870 | 4073 | return &hstates[i]; |
9a305230 LS |
4074 | } |
4075 | ||
4076 | return kobj_to_node_hstate(kobj, nidp); | |
a3437870 NA |
4077 | } |
4078 | ||
06808b08 | 4079 | static ssize_t nr_hugepages_show_common(struct kobject *kobj, |
a3437870 NA |
4080 | struct kobj_attribute *attr, char *buf) |
4081 | { | |
9a305230 LS |
4082 | struct hstate *h; |
4083 | unsigned long nr_huge_pages; | |
4084 | int nid; | |
4085 | ||
4086 | h = kobj_to_hstate(kobj, &nid); | |
4087 | if (nid == NUMA_NO_NODE) | |
4088 | nr_huge_pages = h->nr_huge_pages; | |
4089 | else | |
4090 | nr_huge_pages = h->nr_huge_pages_node[nid]; | |
4091 | ||
ae7a927d | 4092 | return sysfs_emit(buf, "%lu\n", nr_huge_pages); |
a3437870 | 4093 | } |
adbe8726 | 4094 | |
238d3c13 DR |
4095 | static ssize_t __nr_hugepages_store_common(bool obey_mempolicy, |
4096 | struct hstate *h, int nid, | |
4097 | unsigned long count, size_t len) | |
a3437870 NA |
4098 | { |
4099 | int err; | |
2d0adf7e | 4100 | nodemask_t nodes_allowed, *n_mask; |
a3437870 | 4101 | |
2d0adf7e OS |
4102 | if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) |
4103 | return -EINVAL; | |
adbe8726 | 4104 | |
9a305230 LS |
4105 | if (nid == NUMA_NO_NODE) { |
4106 | /* | |
4107 | * global hstate attribute | |
4108 | */ | |
4109 | if (!(obey_mempolicy && | |
2d0adf7e OS |
4110 | init_nodemask_of_mempolicy(&nodes_allowed))) |
4111 | n_mask = &node_states[N_MEMORY]; | |
4112 | else | |
4113 | n_mask = &nodes_allowed; | |
4114 | } else { | |
9a305230 | 4115 | /* |
fd875dca MK |
4116 | * Node specific request. count adjustment happens in |
4117 | * set_max_huge_pages() after acquiring hugetlb_lock. | |
9a305230 | 4118 | */ |
2d0adf7e OS |
4119 | init_nodemask_of_node(&nodes_allowed, nid); |
4120 | n_mask = &nodes_allowed; | |
fd875dca | 4121 | } |
9a305230 | 4122 | |
2d0adf7e | 4123 | err = set_max_huge_pages(h, count, nid, n_mask); |
06808b08 | 4124 | |
4eb0716e | 4125 | return err ? err : len; |
06808b08 LS |
4126 | } |
4127 | ||
238d3c13 DR |
4128 | static ssize_t nr_hugepages_store_common(bool obey_mempolicy, |
4129 | struct kobject *kobj, const char *buf, | |
4130 | size_t len) | |
4131 | { | |
4132 | struct hstate *h; | |
4133 | unsigned long count; | |
4134 | int nid; | |
4135 | int err; | |
4136 | ||
4137 | err = kstrtoul(buf, 10, &count); | |
4138 | if (err) | |
4139 | return err; | |
4140 | ||
4141 | h = kobj_to_hstate(kobj, &nid); | |
4142 | return __nr_hugepages_store_common(obey_mempolicy, h, nid, count, len); | |
4143 | } | |
4144 | ||
06808b08 LS |
4145 | static ssize_t nr_hugepages_show(struct kobject *kobj, |
4146 | struct kobj_attribute *attr, char *buf) | |
4147 | { | |
4148 | return nr_hugepages_show_common(kobj, attr, buf); | |
4149 | } | |
4150 | ||
4151 | static ssize_t nr_hugepages_store(struct kobject *kobj, | |
4152 | struct kobj_attribute *attr, const char *buf, size_t len) | |
4153 | { | |
238d3c13 | 4154 | return nr_hugepages_store_common(false, kobj, buf, len); |
a3437870 NA |
4155 | } |
4156 | HSTATE_ATTR(nr_hugepages); | |
4157 | ||
06808b08 LS |
4158 | #ifdef CONFIG_NUMA |
4159 | ||
4160 | /* | |
4161 | * hstate attribute for optionally mempolicy-based constraint on persistent | |
4162 | * huge page alloc/free. | |
4163 | */ | |
4164 | static ssize_t nr_hugepages_mempolicy_show(struct kobject *kobj, | |
ae7a927d JP |
4165 | struct kobj_attribute *attr, |
4166 | char *buf) | |
06808b08 LS |
4167 | { |
4168 | return nr_hugepages_show_common(kobj, attr, buf); | |
4169 | } | |
4170 | ||
4171 | static ssize_t nr_hugepages_mempolicy_store(struct kobject *kobj, | |
4172 | struct kobj_attribute *attr, const char *buf, size_t len) | |
4173 | { | |
238d3c13 | 4174 | return nr_hugepages_store_common(true, kobj, buf, len); |
06808b08 LS |
4175 | } |
4176 | HSTATE_ATTR(nr_hugepages_mempolicy); | |
4177 | #endif | |
4178 | ||
4179 | ||
a3437870 NA |
4180 | static ssize_t nr_overcommit_hugepages_show(struct kobject *kobj, |
4181 | struct kobj_attribute *attr, char *buf) | |
4182 | { | |
9a305230 | 4183 | struct hstate *h = kobj_to_hstate(kobj, NULL); |
ae7a927d | 4184 | return sysfs_emit(buf, "%lu\n", h->nr_overcommit_huge_pages); |
a3437870 | 4185 | } |
adbe8726 | 4186 | |
a3437870 NA |
4187 | static ssize_t nr_overcommit_hugepages_store(struct kobject *kobj, |
4188 | struct kobj_attribute *attr, const char *buf, size_t count) | |
4189 | { | |
4190 | int err; | |
4191 | unsigned long input; | |
9a305230 | 4192 | struct hstate *h = kobj_to_hstate(kobj, NULL); |
a3437870 | 4193 | |
bae7f4ae | 4194 | if (hstate_is_gigantic(h)) |
adbe8726 EM |
4195 | return -EINVAL; |
4196 | ||
3dbb95f7 | 4197 | err = kstrtoul(buf, 10, &input); |
a3437870 | 4198 | if (err) |
73ae31e5 | 4199 | return err; |
a3437870 | 4200 | |
db71ef79 | 4201 | spin_lock_irq(&hugetlb_lock); |
a3437870 | 4202 | h->nr_overcommit_huge_pages = input; |
db71ef79 | 4203 | spin_unlock_irq(&hugetlb_lock); |
a3437870 NA |
4204 | |
4205 | return count; | |
4206 | } | |
4207 | HSTATE_ATTR(nr_overcommit_hugepages); | |
4208 | ||
4209 | static ssize_t free_hugepages_show(struct kobject *kobj, | |
4210 | struct kobj_attribute *attr, char *buf) | |
4211 | { | |
9a305230 LS |
4212 | struct hstate *h; |
4213 | unsigned long free_huge_pages; | |
4214 | int nid; | |
4215 | ||
4216 | h = kobj_to_hstate(kobj, &nid); | |
4217 | if (nid == NUMA_NO_NODE) | |
4218 | free_huge_pages = h->free_huge_pages; | |
4219 | else | |
4220 | free_huge_pages = h->free_huge_pages_node[nid]; | |
4221 | ||
ae7a927d | 4222 | return sysfs_emit(buf, "%lu\n", free_huge_pages); |
a3437870 NA |
4223 | } |
4224 | HSTATE_ATTR_RO(free_hugepages); | |
4225 | ||
4226 | static ssize_t resv_hugepages_show(struct kobject *kobj, | |
4227 | struct kobj_attribute *attr, char *buf) | |
4228 | { | |
9a305230 | 4229 | struct hstate *h = kobj_to_hstate(kobj, NULL); |
ae7a927d | 4230 | return sysfs_emit(buf, "%lu\n", h->resv_huge_pages); |
a3437870 NA |
4231 | } |
4232 | HSTATE_ATTR_RO(resv_hugepages); | |
4233 | ||
4234 | static ssize_t surplus_hugepages_show(struct kobject *kobj, | |
4235 | struct kobj_attribute *attr, char *buf) | |
4236 | { | |
9a305230 LS |
4237 | struct hstate *h; |
4238 | unsigned long surplus_huge_pages; | |
4239 | int nid; | |
4240 | ||
4241 | h = kobj_to_hstate(kobj, &nid); | |
4242 | if (nid == NUMA_NO_NODE) | |
4243 | surplus_huge_pages = h->surplus_huge_pages; | |
4244 | else | |
4245 | surplus_huge_pages = h->surplus_huge_pages_node[nid]; | |
4246 | ||
ae7a927d | 4247 | return sysfs_emit(buf, "%lu\n", surplus_huge_pages); |
a3437870 NA |
4248 | } |
4249 | HSTATE_ATTR_RO(surplus_hugepages); | |
4250 | ||
79dfc695 MK |
4251 | static ssize_t demote_store(struct kobject *kobj, |
4252 | struct kobj_attribute *attr, const char *buf, size_t len) | |
4253 | { | |
4254 | unsigned long nr_demote; | |
4255 | unsigned long nr_available; | |
4256 | nodemask_t nodes_allowed, *n_mask; | |
4257 | struct hstate *h; | |
8eeda55f | 4258 | int err; |
79dfc695 MK |
4259 | int nid; |
4260 | ||
4261 | err = kstrtoul(buf, 10, &nr_demote); | |
4262 | if (err) | |
4263 | return err; | |
4264 | h = kobj_to_hstate(kobj, &nid); | |
4265 | ||
4266 | if (nid != NUMA_NO_NODE) { | |
4267 | init_nodemask_of_node(&nodes_allowed, nid); | |
4268 | n_mask = &nodes_allowed; | |
4269 | } else { | |
4270 | n_mask = &node_states[N_MEMORY]; | |
4271 | } | |
4272 | ||
4273 | /* Synchronize with other sysfs operations modifying huge pages */ | |
4274 | mutex_lock(&h->resize_lock); | |
4275 | spin_lock_irq(&hugetlb_lock); | |
4276 | ||
4277 | while (nr_demote) { | |
4278 | /* | |
4279 | * Check for available pages to demote each time thorough the | |
4280 | * loop as demote_pool_huge_page will drop hugetlb_lock. | |
79dfc695 MK |
4281 | */ |
4282 | if (nid != NUMA_NO_NODE) | |
4283 | nr_available = h->free_huge_pages_node[nid]; | |
4284 | else | |
4285 | nr_available = h->free_huge_pages; | |
4286 | nr_available -= h->resv_huge_pages; | |
4287 | if (!nr_available) | |
4288 | break; | |
4289 | ||
4290 | err = demote_pool_huge_page(h, n_mask); | |
4291 | if (err) | |
4292 | break; | |
4293 | ||
4294 | nr_demote--; | |
4295 | } | |
4296 | ||
4297 | spin_unlock_irq(&hugetlb_lock); | |
4298 | mutex_unlock(&h->resize_lock); | |
4299 | ||
4300 | if (err) | |
4301 | return err; | |
4302 | return len; | |
4303 | } | |
4304 | HSTATE_ATTR_WO(demote); | |
4305 | ||
4306 | static ssize_t demote_size_show(struct kobject *kobj, | |
4307 | struct kobj_attribute *attr, char *buf) | |
4308 | { | |
12658abf | 4309 | struct hstate *h = kobj_to_hstate(kobj, NULL); |
79dfc695 MK |
4310 | unsigned long demote_size = (PAGE_SIZE << h->demote_order) / SZ_1K; |
4311 | ||
4312 | return sysfs_emit(buf, "%lukB\n", demote_size); | |
4313 | } | |
4314 | ||
4315 | static ssize_t demote_size_store(struct kobject *kobj, | |
4316 | struct kobj_attribute *attr, | |
4317 | const char *buf, size_t count) | |
4318 | { | |
4319 | struct hstate *h, *demote_hstate; | |
4320 | unsigned long demote_size; | |
4321 | unsigned int demote_order; | |
79dfc695 MK |
4322 | |
4323 | demote_size = (unsigned long)memparse(buf, NULL); | |
4324 | ||
4325 | demote_hstate = size_to_hstate(demote_size); | |
4326 | if (!demote_hstate) | |
4327 | return -EINVAL; | |
4328 | demote_order = demote_hstate->order; | |
a01f4390 MK |
4329 | if (demote_order < HUGETLB_PAGE_ORDER) |
4330 | return -EINVAL; | |
79dfc695 MK |
4331 | |
4332 | /* demote order must be smaller than hstate order */ | |
12658abf | 4333 | h = kobj_to_hstate(kobj, NULL); |
79dfc695 MK |
4334 | if (demote_order >= h->order) |
4335 | return -EINVAL; | |
4336 | ||
4337 | /* resize_lock synchronizes access to demote size and writes */ | |
4338 | mutex_lock(&h->resize_lock); | |
4339 | h->demote_order = demote_order; | |
4340 | mutex_unlock(&h->resize_lock); | |
4341 | ||
4342 | return count; | |
4343 | } | |
4344 | HSTATE_ATTR(demote_size); | |
4345 | ||
a3437870 NA |
4346 | static struct attribute *hstate_attrs[] = { |
4347 | &nr_hugepages_attr.attr, | |
4348 | &nr_overcommit_hugepages_attr.attr, | |
4349 | &free_hugepages_attr.attr, | |
4350 | &resv_hugepages_attr.attr, | |
4351 | &surplus_hugepages_attr.attr, | |
06808b08 LS |
4352 | #ifdef CONFIG_NUMA |
4353 | &nr_hugepages_mempolicy_attr.attr, | |
4354 | #endif | |
a3437870 NA |
4355 | NULL, |
4356 | }; | |
4357 | ||
67e5ed96 | 4358 | static const struct attribute_group hstate_attr_group = { |
a3437870 NA |
4359 | .attrs = hstate_attrs, |
4360 | }; | |
4361 | ||
79dfc695 MK |
4362 | static struct attribute *hstate_demote_attrs[] = { |
4363 | &demote_size_attr.attr, | |
4364 | &demote_attr.attr, | |
4365 | NULL, | |
4366 | }; | |
4367 | ||
4368 | static const struct attribute_group hstate_demote_attr_group = { | |
4369 | .attrs = hstate_demote_attrs, | |
4370 | }; | |
4371 | ||
094e9539 JM |
4372 | static int hugetlb_sysfs_add_hstate(struct hstate *h, struct kobject *parent, |
4373 | struct kobject **hstate_kobjs, | |
67e5ed96 | 4374 | const struct attribute_group *hstate_attr_group) |
a3437870 NA |
4375 | { |
4376 | int retval; | |
972dc4de | 4377 | int hi = hstate_index(h); |
a3437870 | 4378 | |
9a305230 LS |
4379 | hstate_kobjs[hi] = kobject_create_and_add(h->name, parent); |
4380 | if (!hstate_kobjs[hi]) | |
a3437870 NA |
4381 | return -ENOMEM; |
4382 | ||
9a305230 | 4383 | retval = sysfs_create_group(hstate_kobjs[hi], hstate_attr_group); |
cc2205a6 | 4384 | if (retval) { |
9a305230 | 4385 | kobject_put(hstate_kobjs[hi]); |
cc2205a6 | 4386 | hstate_kobjs[hi] = NULL; |
3a6bdda0 | 4387 | return retval; |
cc2205a6 | 4388 | } |
a3437870 | 4389 | |
79dfc695 | 4390 | if (h->demote_order) { |
01088a60 ML |
4391 | retval = sysfs_create_group(hstate_kobjs[hi], |
4392 | &hstate_demote_attr_group); | |
4393 | if (retval) { | |
79dfc695 | 4394 | pr_warn("HugeTLB unable to create demote interfaces for %s\n", h->name); |
01088a60 ML |
4395 | sysfs_remove_group(hstate_kobjs[hi], hstate_attr_group); |
4396 | kobject_put(hstate_kobjs[hi]); | |
4397 | hstate_kobjs[hi] = NULL; | |
4398 | return retval; | |
4399 | } | |
79dfc695 MK |
4400 | } |
4401 | ||
01088a60 | 4402 | return 0; |
a3437870 NA |
4403 | } |
4404 | ||
9a305230 | 4405 | #ifdef CONFIG_NUMA |
a4a00b45 | 4406 | static bool hugetlb_sysfs_initialized __ro_after_init; |
9a305230 LS |
4407 | |
4408 | /* | |
4409 | * node_hstate/s - associate per node hstate attributes, via their kobjects, | |
10fbcf4c KS |
4410 | * with node devices in node_devices[] using a parallel array. The array |
4411 | * index of a node device or _hstate == node id. | |
4412 | * This is here to avoid any static dependency of the node device driver, in | |
9a305230 LS |
4413 | * the base kernel, on the hugetlb module. |
4414 | */ | |
4415 | struct node_hstate { | |
4416 | struct kobject *hugepages_kobj; | |
4417 | struct kobject *hstate_kobjs[HUGE_MAX_HSTATE]; | |
4418 | }; | |
b4e289a6 | 4419 | static struct node_hstate node_hstates[MAX_NUMNODES]; |
9a305230 LS |
4420 | |
4421 | /* | |
10fbcf4c | 4422 | * A subset of global hstate attributes for node devices |
9a305230 LS |
4423 | */ |
4424 | static struct attribute *per_node_hstate_attrs[] = { | |
4425 | &nr_hugepages_attr.attr, | |
4426 | &free_hugepages_attr.attr, | |
4427 | &surplus_hugepages_attr.attr, | |
4428 | NULL, | |
4429 | }; | |
4430 | ||
67e5ed96 | 4431 | static const struct attribute_group per_node_hstate_attr_group = { |
9a305230 LS |
4432 | .attrs = per_node_hstate_attrs, |
4433 | }; | |
4434 | ||
4435 | /* | |
10fbcf4c | 4436 | * kobj_to_node_hstate - lookup global hstate for node device hstate attr kobj. |
9a305230 LS |
4437 | * Returns node id via non-NULL nidp. |
4438 | */ | |
4439 | static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) | |
4440 | { | |
4441 | int nid; | |
4442 | ||
4443 | for (nid = 0; nid < nr_node_ids; nid++) { | |
4444 | struct node_hstate *nhs = &node_hstates[nid]; | |
4445 | int i; | |
4446 | for (i = 0; i < HUGE_MAX_HSTATE; i++) | |
4447 | if (nhs->hstate_kobjs[i] == kobj) { | |
4448 | if (nidp) | |
4449 | *nidp = nid; | |
4450 | return &hstates[i]; | |
4451 | } | |
4452 | } | |
4453 | ||
4454 | BUG(); | |
4455 | return NULL; | |
4456 | } | |
4457 | ||
4458 | /* | |
10fbcf4c | 4459 | * Unregister hstate attributes from a single node device. |
9a305230 LS |
4460 | * No-op if no hstate attributes attached. |
4461 | */ | |
a4a00b45 | 4462 | void hugetlb_unregister_node(struct node *node) |
9a305230 LS |
4463 | { |
4464 | struct hstate *h; | |
10fbcf4c | 4465 | struct node_hstate *nhs = &node_hstates[node->dev.id]; |
9a305230 LS |
4466 | |
4467 | if (!nhs->hugepages_kobj) | |
9b5e5d0f | 4468 | return; /* no hstate attributes */ |
9a305230 | 4469 | |
972dc4de AK |
4470 | for_each_hstate(h) { |
4471 | int idx = hstate_index(h); | |
01088a60 ML |
4472 | struct kobject *hstate_kobj = nhs->hstate_kobjs[idx]; |
4473 | ||
4474 | if (!hstate_kobj) | |
4475 | continue; | |
4476 | if (h->demote_order) | |
4477 | sysfs_remove_group(hstate_kobj, &hstate_demote_attr_group); | |
4478 | sysfs_remove_group(hstate_kobj, &per_node_hstate_attr_group); | |
4479 | kobject_put(hstate_kobj); | |
4480 | nhs->hstate_kobjs[idx] = NULL; | |
972dc4de | 4481 | } |
9a305230 LS |
4482 | |
4483 | kobject_put(nhs->hugepages_kobj); | |
4484 | nhs->hugepages_kobj = NULL; | |
4485 | } | |
4486 | ||
9a305230 LS |
4487 | |
4488 | /* | |
10fbcf4c | 4489 | * Register hstate attributes for a single node device. |
9a305230 LS |
4490 | * No-op if attributes already registered. |
4491 | */ | |
a4a00b45 | 4492 | void hugetlb_register_node(struct node *node) |
9a305230 LS |
4493 | { |
4494 | struct hstate *h; | |
10fbcf4c | 4495 | struct node_hstate *nhs = &node_hstates[node->dev.id]; |
9a305230 LS |
4496 | int err; |
4497 | ||
a4a00b45 MS |
4498 | if (!hugetlb_sysfs_initialized) |
4499 | return; | |
4500 | ||
9a305230 LS |
4501 | if (nhs->hugepages_kobj) |
4502 | return; /* already allocated */ | |
4503 | ||
4504 | nhs->hugepages_kobj = kobject_create_and_add("hugepages", | |
10fbcf4c | 4505 | &node->dev.kobj); |
9a305230 LS |
4506 | if (!nhs->hugepages_kobj) |
4507 | return; | |
4508 | ||
4509 | for_each_hstate(h) { | |
4510 | err = hugetlb_sysfs_add_hstate(h, nhs->hugepages_kobj, | |
4511 | nhs->hstate_kobjs, | |
4512 | &per_node_hstate_attr_group); | |
4513 | if (err) { | |
282f4214 | 4514 | pr_err("HugeTLB: Unable to add hstate %s for node %d\n", |
ffb22af5 | 4515 | h->name, node->dev.id); |
9a305230 LS |
4516 | hugetlb_unregister_node(node); |
4517 | break; | |
4518 | } | |
4519 | } | |
4520 | } | |
4521 | ||
4522 | /* | |
9b5e5d0f | 4523 | * hugetlb init time: register hstate attributes for all registered node |
10fbcf4c KS |
4524 | * devices of nodes that have memory. All on-line nodes should have |
4525 | * registered their associated device by this time. | |
9a305230 | 4526 | */ |
7d9ca000 | 4527 | static void __init hugetlb_register_all_nodes(void) |
9a305230 LS |
4528 | { |
4529 | int nid; | |
4530 | ||
a4a00b45 | 4531 | for_each_online_node(nid) |
b958d4d0 | 4532 | hugetlb_register_node(node_devices[nid]); |
9a305230 LS |
4533 | } |
4534 | #else /* !CONFIG_NUMA */ | |
4535 | ||
4536 | static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) | |
4537 | { | |
4538 | BUG(); | |
4539 | if (nidp) | |
4540 | *nidp = -1; | |
4541 | return NULL; | |
4542 | } | |
4543 | ||
9a305230 LS |
4544 | static void hugetlb_register_all_nodes(void) { } |
4545 | ||
4546 | #endif | |
4547 | ||
263b8998 ML |
4548 | #ifdef CONFIG_CMA |
4549 | static void __init hugetlb_cma_check(void); | |
4550 | #else | |
4551 | static inline __init void hugetlb_cma_check(void) | |
4552 | { | |
4553 | } | |
4554 | #endif | |
4555 | ||
a4a00b45 MS |
4556 | static void __init hugetlb_sysfs_init(void) |
4557 | { | |
4558 | struct hstate *h; | |
4559 | int err; | |
4560 | ||
4561 | hugepages_kobj = kobject_create_and_add("hugepages", mm_kobj); | |
4562 | if (!hugepages_kobj) | |
4563 | return; | |
4564 | ||
4565 | for_each_hstate(h) { | |
4566 | err = hugetlb_sysfs_add_hstate(h, hugepages_kobj, | |
4567 | hstate_kobjs, &hstate_attr_group); | |
4568 | if (err) | |
4569 | pr_err("HugeTLB: Unable to add hstate %s", h->name); | |
4570 | } | |
4571 | ||
4572 | #ifdef CONFIG_NUMA | |
4573 | hugetlb_sysfs_initialized = true; | |
4574 | #endif | |
4575 | hugetlb_register_all_nodes(); | |
4576 | } | |
4577 | ||
962de548 KW |
4578 | #ifdef CONFIG_SYSCTL |
4579 | static void hugetlb_sysctl_init(void); | |
4580 | #else | |
4581 | static inline void hugetlb_sysctl_init(void) { } | |
4582 | #endif | |
4583 | ||
a3437870 NA |
4584 | static int __init hugetlb_init(void) |
4585 | { | |
8382d914 DB |
4586 | int i; |
4587 | ||
d6995da3 MK |
4588 | BUILD_BUG_ON(sizeof_field(struct page, private) * BITS_PER_BYTE < |
4589 | __NR_HPAGEFLAGS); | |
4590 | ||
c2833a5b MK |
4591 | if (!hugepages_supported()) { |
4592 | if (hugetlb_max_hstate || default_hstate_max_huge_pages) | |
4593 | pr_warn("HugeTLB: huge pages not supported, ignoring associated command-line parameters\n"); | |
0ef89d25 | 4594 | return 0; |
c2833a5b | 4595 | } |
a3437870 | 4596 | |
282f4214 MK |
4597 | /* |
4598 | * Make sure HPAGE_SIZE (HUGETLB_PAGE_ORDER) hstate exists. Some | |
4599 | * architectures depend on setup being done here. | |
4600 | */ | |
4601 | hugetlb_add_hstate(HUGETLB_PAGE_ORDER); | |
4602 | if (!parsed_default_hugepagesz) { | |
4603 | /* | |
4604 | * If we did not parse a default huge page size, set | |
4605 | * default_hstate_idx to HPAGE_SIZE hstate. And, if the | |
4606 | * number of huge pages for this default size was implicitly | |
4607 | * specified, set that here as well. | |
4608 | * Note that the implicit setting will overwrite an explicit | |
4609 | * setting. A warning will be printed in this case. | |
4610 | */ | |
4611 | default_hstate_idx = hstate_index(size_to_hstate(HPAGE_SIZE)); | |
4612 | if (default_hstate_max_huge_pages) { | |
4613 | if (default_hstate.max_huge_pages) { | |
4614 | char buf[32]; | |
4615 | ||
4616 | string_get_size(huge_page_size(&default_hstate), | |
4617 | 1, STRING_UNITS_2, buf, 32); | |
4618 | pr_warn("HugeTLB: Ignoring hugepages=%lu associated with %s page size\n", | |
4619 | default_hstate.max_huge_pages, buf); | |
4620 | pr_warn("HugeTLB: Using hugepages=%lu for number of default huge pages\n", | |
4621 | default_hstate_max_huge_pages); | |
4622 | } | |
4623 | default_hstate.max_huge_pages = | |
4624 | default_hstate_max_huge_pages; | |
b5389086 | 4625 | |
0a7a0f6f | 4626 | for_each_online_node(i) |
b5389086 ZY |
4627 | default_hstate.max_huge_pages_node[i] = |
4628 | default_hugepages_in_node[i]; | |
d715cf80 | 4629 | } |
f8b74815 | 4630 | } |
a3437870 | 4631 | |
cf11e85f | 4632 | hugetlb_cma_check(); |
a3437870 | 4633 | hugetlb_init_hstates(); |
aa888a74 | 4634 | gather_bootmem_prealloc(); |
a3437870 NA |
4635 | report_hugepages(); |
4636 | ||
4637 | hugetlb_sysfs_init(); | |
7179e7bf | 4638 | hugetlb_cgroup_file_init(); |
962de548 | 4639 | hugetlb_sysctl_init(); |
9a305230 | 4640 | |
8382d914 DB |
4641 | #ifdef CONFIG_SMP |
4642 | num_fault_mutexes = roundup_pow_of_two(8 * num_possible_cpus()); | |
4643 | #else | |
4644 | num_fault_mutexes = 1; | |
4645 | #endif | |
c672c7f2 | 4646 | hugetlb_fault_mutex_table = |
6da2ec56 KC |
4647 | kmalloc_array(num_fault_mutexes, sizeof(struct mutex), |
4648 | GFP_KERNEL); | |
c672c7f2 | 4649 | BUG_ON(!hugetlb_fault_mutex_table); |
8382d914 DB |
4650 | |
4651 | for (i = 0; i < num_fault_mutexes; i++) | |
c672c7f2 | 4652 | mutex_init(&hugetlb_fault_mutex_table[i]); |
a3437870 NA |
4653 | return 0; |
4654 | } | |
3e89e1c5 | 4655 | subsys_initcall(hugetlb_init); |
a3437870 | 4656 | |
ae94da89 MK |
4657 | /* Overwritten by architectures with more huge page sizes */ |
4658 | bool __init __attribute((weak)) arch_hugetlb_valid_size(unsigned long size) | |
9fee021d | 4659 | { |
ae94da89 | 4660 | return size == HPAGE_SIZE; |
9fee021d VT |
4661 | } |
4662 | ||
d00181b9 | 4663 | void __init hugetlb_add_hstate(unsigned int order) |
a3437870 NA |
4664 | { |
4665 | struct hstate *h; | |
8faa8b07 AK |
4666 | unsigned long i; |
4667 | ||
a3437870 | 4668 | if (size_to_hstate(PAGE_SIZE << order)) { |
a3437870 NA |
4669 | return; |
4670 | } | |
47d38344 | 4671 | BUG_ON(hugetlb_max_hstate >= HUGE_MAX_HSTATE); |
59838b25 | 4672 | BUG_ON(order < order_base_2(__NR_USED_SUBPAGE)); |
47d38344 | 4673 | h = &hstates[hugetlb_max_hstate++]; |
29383967 | 4674 | mutex_init(&h->resize_lock); |
a3437870 | 4675 | h->order = order; |
aca78307 | 4676 | h->mask = ~(huge_page_size(h) - 1); |
8faa8b07 AK |
4677 | for (i = 0; i < MAX_NUMNODES; ++i) |
4678 | INIT_LIST_HEAD(&h->hugepage_freelists[i]); | |
0edaecfa | 4679 | INIT_LIST_HEAD(&h->hugepage_activelist); |
54f18d35 AM |
4680 | h->next_nid_to_alloc = first_memory_node; |
4681 | h->next_nid_to_free = first_memory_node; | |
a3437870 | 4682 | snprintf(h->name, HSTATE_NAME_LEN, "hugepages-%lukB", |
c2c3a60a | 4683 | huge_page_size(h)/SZ_1K); |
8faa8b07 | 4684 | |
a3437870 NA |
4685 | parsed_hstate = h; |
4686 | } | |
4687 | ||
b5389086 ZY |
4688 | bool __init __weak hugetlb_node_alloc_supported(void) |
4689 | { | |
4690 | return true; | |
4691 | } | |
f87442f4 PL |
4692 | |
4693 | static void __init hugepages_clear_pages_in_node(void) | |
4694 | { | |
4695 | if (!hugetlb_max_hstate) { | |
4696 | default_hstate_max_huge_pages = 0; | |
4697 | memset(default_hugepages_in_node, 0, | |
10395680 | 4698 | sizeof(default_hugepages_in_node)); |
f87442f4 PL |
4699 | } else { |
4700 | parsed_hstate->max_huge_pages = 0; | |
4701 | memset(parsed_hstate->max_huge_pages_node, 0, | |
10395680 | 4702 | sizeof(parsed_hstate->max_huge_pages_node)); |
f87442f4 PL |
4703 | } |
4704 | } | |
4705 | ||
282f4214 MK |
4706 | /* |
4707 | * hugepages command line processing | |
4708 | * hugepages normally follows a valid hugepagsz or default_hugepagsz | |
4709 | * specification. If not, ignore the hugepages value. hugepages can also | |
4710 | * be the first huge page command line option in which case it implicitly | |
4711 | * specifies the number of huge pages for the default size. | |
4712 | */ | |
4713 | static int __init hugepages_setup(char *s) | |
a3437870 NA |
4714 | { |
4715 | unsigned long *mhp; | |
8faa8b07 | 4716 | static unsigned long *last_mhp; |
b5389086 ZY |
4717 | int node = NUMA_NO_NODE; |
4718 | int count; | |
4719 | unsigned long tmp; | |
4720 | char *p = s; | |
a3437870 | 4721 | |
9fee021d | 4722 | if (!parsed_valid_hugepagesz) { |
282f4214 | 4723 | pr_warn("HugeTLB: hugepages=%s does not follow a valid hugepagesz, ignoring\n", s); |
9fee021d | 4724 | parsed_valid_hugepagesz = true; |
f81f6e4b | 4725 | return 1; |
9fee021d | 4726 | } |
282f4214 | 4727 | |
a3437870 | 4728 | /* |
282f4214 MK |
4729 | * !hugetlb_max_hstate means we haven't parsed a hugepagesz= parameter |
4730 | * yet, so this hugepages= parameter goes to the "default hstate". | |
4731 | * Otherwise, it goes with the previously parsed hugepagesz or | |
4732 | * default_hugepagesz. | |
a3437870 | 4733 | */ |
9fee021d | 4734 | else if (!hugetlb_max_hstate) |
a3437870 NA |
4735 | mhp = &default_hstate_max_huge_pages; |
4736 | else | |
4737 | mhp = &parsed_hstate->max_huge_pages; | |
4738 | ||
8faa8b07 | 4739 | if (mhp == last_mhp) { |
282f4214 | 4740 | pr_warn("HugeTLB: hugepages= specified twice without interleaving hugepagesz=, ignoring hugepages=%s\n", s); |
f81f6e4b | 4741 | return 1; |
8faa8b07 AK |
4742 | } |
4743 | ||
b5389086 ZY |
4744 | while (*p) { |
4745 | count = 0; | |
4746 | if (sscanf(p, "%lu%n", &tmp, &count) != 1) | |
4747 | goto invalid; | |
4748 | /* Parameter is node format */ | |
4749 | if (p[count] == ':') { | |
4750 | if (!hugetlb_node_alloc_supported()) { | |
4751 | pr_warn("HugeTLB: architecture can't support node specific alloc, ignoring!\n"); | |
f81f6e4b | 4752 | return 1; |
b5389086 | 4753 | } |
0a7a0f6f | 4754 | if (tmp >= MAX_NUMNODES || !node_online(tmp)) |
e79ce983 | 4755 | goto invalid; |
0a7a0f6f | 4756 | node = array_index_nospec(tmp, MAX_NUMNODES); |
b5389086 | 4757 | p += count + 1; |
b5389086 ZY |
4758 | /* Parse hugepages */ |
4759 | if (sscanf(p, "%lu%n", &tmp, &count) != 1) | |
4760 | goto invalid; | |
4761 | if (!hugetlb_max_hstate) | |
4762 | default_hugepages_in_node[node] = tmp; | |
4763 | else | |
4764 | parsed_hstate->max_huge_pages_node[node] = tmp; | |
4765 | *mhp += tmp; | |
4766 | /* Go to parse next node*/ | |
4767 | if (p[count] == ',') | |
4768 | p += count + 1; | |
4769 | else | |
4770 | break; | |
4771 | } else { | |
4772 | if (p != s) | |
4773 | goto invalid; | |
4774 | *mhp = tmp; | |
4775 | break; | |
4776 | } | |
4777 | } | |
a3437870 | 4778 | |
8faa8b07 AK |
4779 | /* |
4780 | * Global state is always initialized later in hugetlb_init. | |
04adbc3f | 4781 | * But we need to allocate gigantic hstates here early to still |
8faa8b07 AK |
4782 | * use the bootmem allocator. |
4783 | */ | |
04adbc3f | 4784 | if (hugetlb_max_hstate && hstate_is_gigantic(parsed_hstate)) |
8faa8b07 AK |
4785 | hugetlb_hstate_alloc_pages(parsed_hstate); |
4786 | ||
4787 | last_mhp = mhp; | |
4788 | ||
a3437870 | 4789 | return 1; |
b5389086 ZY |
4790 | |
4791 | invalid: | |
4792 | pr_warn("HugeTLB: Invalid hugepages parameter %s\n", p); | |
f87442f4 | 4793 | hugepages_clear_pages_in_node(); |
f81f6e4b | 4794 | return 1; |
a3437870 | 4795 | } |
282f4214 | 4796 | __setup("hugepages=", hugepages_setup); |
e11bfbfc | 4797 | |
282f4214 MK |
4798 | /* |
4799 | * hugepagesz command line processing | |
4800 | * A specific huge page size can only be specified once with hugepagesz. | |
4801 | * hugepagesz is followed by hugepages on the command line. The global | |
4802 | * variable 'parsed_valid_hugepagesz' is used to determine if prior | |
4803 | * hugepagesz argument was valid. | |
4804 | */ | |
359f2544 | 4805 | static int __init hugepagesz_setup(char *s) |
e11bfbfc | 4806 | { |
359f2544 | 4807 | unsigned long size; |
282f4214 MK |
4808 | struct hstate *h; |
4809 | ||
4810 | parsed_valid_hugepagesz = false; | |
359f2544 MK |
4811 | size = (unsigned long)memparse(s, NULL); |
4812 | ||
4813 | if (!arch_hugetlb_valid_size(size)) { | |
282f4214 | 4814 | pr_err("HugeTLB: unsupported hugepagesz=%s\n", s); |
f81f6e4b | 4815 | return 1; |
359f2544 MK |
4816 | } |
4817 | ||
282f4214 MK |
4818 | h = size_to_hstate(size); |
4819 | if (h) { | |
4820 | /* | |
4821 | * hstate for this size already exists. This is normally | |
4822 | * an error, but is allowed if the existing hstate is the | |
4823 | * default hstate. More specifically, it is only allowed if | |
4824 | * the number of huge pages for the default hstate was not | |
4825 | * previously specified. | |
4826 | */ | |
4827 | if (!parsed_default_hugepagesz || h != &default_hstate || | |
4828 | default_hstate.max_huge_pages) { | |
4829 | pr_warn("HugeTLB: hugepagesz=%s specified twice, ignoring\n", s); | |
f81f6e4b | 4830 | return 1; |
282f4214 MK |
4831 | } |
4832 | ||
4833 | /* | |
4834 | * No need to call hugetlb_add_hstate() as hstate already | |
4835 | * exists. But, do set parsed_hstate so that a following | |
4836 | * hugepages= parameter will be applied to this hstate. | |
4837 | */ | |
4838 | parsed_hstate = h; | |
4839 | parsed_valid_hugepagesz = true; | |
4840 | return 1; | |
38237830 MK |
4841 | } |
4842 | ||
359f2544 | 4843 | hugetlb_add_hstate(ilog2(size) - PAGE_SHIFT); |
282f4214 | 4844 | parsed_valid_hugepagesz = true; |
e11bfbfc NP |
4845 | return 1; |
4846 | } | |
359f2544 MK |
4847 | __setup("hugepagesz=", hugepagesz_setup); |
4848 | ||
282f4214 MK |
4849 | /* |
4850 | * default_hugepagesz command line input | |
4851 | * Only one instance of default_hugepagesz allowed on command line. | |
4852 | */ | |
ae94da89 | 4853 | static int __init default_hugepagesz_setup(char *s) |
e11bfbfc | 4854 | { |
ae94da89 | 4855 | unsigned long size; |
b5389086 | 4856 | int i; |
ae94da89 | 4857 | |
282f4214 | 4858 | parsed_valid_hugepagesz = false; |
282f4214 MK |
4859 | if (parsed_default_hugepagesz) { |
4860 | pr_err("HugeTLB: default_hugepagesz previously specified, ignoring %s\n", s); | |
f81f6e4b | 4861 | return 1; |
282f4214 MK |
4862 | } |
4863 | ||
ae94da89 MK |
4864 | size = (unsigned long)memparse(s, NULL); |
4865 | ||
4866 | if (!arch_hugetlb_valid_size(size)) { | |
282f4214 | 4867 | pr_err("HugeTLB: unsupported default_hugepagesz=%s\n", s); |
f81f6e4b | 4868 | return 1; |
ae94da89 MK |
4869 | } |
4870 | ||
282f4214 MK |
4871 | hugetlb_add_hstate(ilog2(size) - PAGE_SHIFT); |
4872 | parsed_valid_hugepagesz = true; | |
4873 | parsed_default_hugepagesz = true; | |
4874 | default_hstate_idx = hstate_index(size_to_hstate(size)); | |
4875 | ||
4876 | /* | |
4877 | * The number of default huge pages (for this size) could have been | |
4878 | * specified as the first hugetlb parameter: hugepages=X. If so, | |
4879 | * then default_hstate_max_huge_pages is set. If the default huge | |
5e0a760b | 4880 | * page size is gigantic (> MAX_PAGE_ORDER), then the pages must be |
282f4214 MK |
4881 | * allocated here from bootmem allocator. |
4882 | */ | |
4883 | if (default_hstate_max_huge_pages) { | |
4884 | default_hstate.max_huge_pages = default_hstate_max_huge_pages; | |
0a7a0f6f | 4885 | for_each_online_node(i) |
b5389086 ZY |
4886 | default_hstate.max_huge_pages_node[i] = |
4887 | default_hugepages_in_node[i]; | |
282f4214 MK |
4888 | if (hstate_is_gigantic(&default_hstate)) |
4889 | hugetlb_hstate_alloc_pages(&default_hstate); | |
4890 | default_hstate_max_huge_pages = 0; | |
4891 | } | |
4892 | ||
e11bfbfc NP |
4893 | return 1; |
4894 | } | |
ae94da89 | 4895 | __setup("default_hugepagesz=", default_hugepagesz_setup); |
a3437870 | 4896 | |
d2226ebd FT |
4897 | static nodemask_t *policy_mbind_nodemask(gfp_t gfp) |
4898 | { | |
4899 | #ifdef CONFIG_NUMA | |
4900 | struct mempolicy *mpol = get_task_policy(current); | |
4901 | ||
4902 | /* | |
4903 | * Only enforce MPOL_BIND policy which overlaps with cpuset policy | |
4904 | * (from policy_nodemask) specifically for hugetlb case | |
4905 | */ | |
4906 | if (mpol->mode == MPOL_BIND && | |
4907 | (apply_policy_zone(mpol, gfp_zone(gfp)) && | |
4908 | cpuset_nodemask_valid_mems_allowed(&mpol->nodes))) | |
4909 | return &mpol->nodes; | |
4910 | #endif | |
4911 | return NULL; | |
4912 | } | |
4913 | ||
8ca39e68 | 4914 | static unsigned int allowed_mems_nr(struct hstate *h) |
8a213460 NA |
4915 | { |
4916 | int node; | |
4917 | unsigned int nr = 0; | |
d2226ebd | 4918 | nodemask_t *mbind_nodemask; |
8ca39e68 MS |
4919 | unsigned int *array = h->free_huge_pages_node; |
4920 | gfp_t gfp_mask = htlb_alloc_mask(h); | |
4921 | ||
d2226ebd | 4922 | mbind_nodemask = policy_mbind_nodemask(gfp_mask); |
8ca39e68 | 4923 | for_each_node_mask(node, cpuset_current_mems_allowed) { |
d2226ebd | 4924 | if (!mbind_nodemask || node_isset(node, *mbind_nodemask)) |
8ca39e68 MS |
4925 | nr += array[node]; |
4926 | } | |
8a213460 NA |
4927 | |
4928 | return nr; | |
4929 | } | |
4930 | ||
4931 | #ifdef CONFIG_SYSCTL | |
17743798 MS |
4932 | static int proc_hugetlb_doulongvec_minmax(struct ctl_table *table, int write, |
4933 | void *buffer, size_t *length, | |
4934 | loff_t *ppos, unsigned long *out) | |
4935 | { | |
4936 | struct ctl_table dup_table; | |
4937 | ||
4938 | /* | |
4939 | * In order to avoid races with __do_proc_doulongvec_minmax(), we | |
4940 | * can duplicate the @table and alter the duplicate of it. | |
4941 | */ | |
4942 | dup_table = *table; | |
4943 | dup_table.data = out; | |
4944 | ||
4945 | return proc_doulongvec_minmax(&dup_table, write, buffer, length, ppos); | |
4946 | } | |
4947 | ||
06808b08 LS |
4948 | static int hugetlb_sysctl_handler_common(bool obey_mempolicy, |
4949 | struct ctl_table *table, int write, | |
32927393 | 4950 | void *buffer, size_t *length, loff_t *ppos) |
1da177e4 | 4951 | { |
e5ff2159 | 4952 | struct hstate *h = &default_hstate; |
238d3c13 | 4953 | unsigned long tmp = h->max_huge_pages; |
08d4a246 | 4954 | int ret; |
e5ff2159 | 4955 | |
457c1b27 | 4956 | if (!hugepages_supported()) |
86613628 | 4957 | return -EOPNOTSUPP; |
457c1b27 | 4958 | |
17743798 MS |
4959 | ret = proc_hugetlb_doulongvec_minmax(table, write, buffer, length, ppos, |
4960 | &tmp); | |
08d4a246 MH |
4961 | if (ret) |
4962 | goto out; | |
e5ff2159 | 4963 | |
238d3c13 DR |
4964 | if (write) |
4965 | ret = __nr_hugepages_store_common(obey_mempolicy, h, | |
4966 | NUMA_NO_NODE, tmp, *length); | |
08d4a246 MH |
4967 | out: |
4968 | return ret; | |
1da177e4 | 4969 | } |
396faf03 | 4970 | |
962de548 | 4971 | static int hugetlb_sysctl_handler(struct ctl_table *table, int write, |
32927393 | 4972 | void *buffer, size_t *length, loff_t *ppos) |
06808b08 LS |
4973 | { |
4974 | ||
4975 | return hugetlb_sysctl_handler_common(false, table, write, | |
4976 | buffer, length, ppos); | |
4977 | } | |
4978 | ||
4979 | #ifdef CONFIG_NUMA | |
962de548 | 4980 | static int hugetlb_mempolicy_sysctl_handler(struct ctl_table *table, int write, |
32927393 | 4981 | void *buffer, size_t *length, loff_t *ppos) |
06808b08 LS |
4982 | { |
4983 | return hugetlb_sysctl_handler_common(true, table, write, | |
4984 | buffer, length, ppos); | |
4985 | } | |
4986 | #endif /* CONFIG_NUMA */ | |
4987 | ||
962de548 | 4988 | static int hugetlb_overcommit_handler(struct ctl_table *table, int write, |
32927393 | 4989 | void *buffer, size_t *length, loff_t *ppos) |
a3d0c6aa | 4990 | { |
a5516438 | 4991 | struct hstate *h = &default_hstate; |
e5ff2159 | 4992 | unsigned long tmp; |
08d4a246 | 4993 | int ret; |
e5ff2159 | 4994 | |
457c1b27 | 4995 | if (!hugepages_supported()) |
86613628 | 4996 | return -EOPNOTSUPP; |
457c1b27 | 4997 | |
c033a93c | 4998 | tmp = h->nr_overcommit_huge_pages; |
e5ff2159 | 4999 | |
bae7f4ae | 5000 | if (write && hstate_is_gigantic(h)) |
adbe8726 EM |
5001 | return -EINVAL; |
5002 | ||
17743798 MS |
5003 | ret = proc_hugetlb_doulongvec_minmax(table, write, buffer, length, ppos, |
5004 | &tmp); | |
08d4a246 MH |
5005 | if (ret) |
5006 | goto out; | |
e5ff2159 AK |
5007 | |
5008 | if (write) { | |
db71ef79 | 5009 | spin_lock_irq(&hugetlb_lock); |
e5ff2159 | 5010 | h->nr_overcommit_huge_pages = tmp; |
db71ef79 | 5011 | spin_unlock_irq(&hugetlb_lock); |
e5ff2159 | 5012 | } |
08d4a246 MH |
5013 | out: |
5014 | return ret; | |
a3d0c6aa NA |
5015 | } |
5016 | ||
962de548 KW |
5017 | static struct ctl_table hugetlb_table[] = { |
5018 | { | |
5019 | .procname = "nr_hugepages", | |
5020 | .data = NULL, | |
5021 | .maxlen = sizeof(unsigned long), | |
5022 | .mode = 0644, | |
5023 | .proc_handler = hugetlb_sysctl_handler, | |
5024 | }, | |
5025 | #ifdef CONFIG_NUMA | |
5026 | { | |
5027 | .procname = "nr_hugepages_mempolicy", | |
5028 | .data = NULL, | |
5029 | .maxlen = sizeof(unsigned long), | |
5030 | .mode = 0644, | |
5031 | .proc_handler = &hugetlb_mempolicy_sysctl_handler, | |
5032 | }, | |
5033 | #endif | |
5034 | { | |
5035 | .procname = "hugetlb_shm_group", | |
5036 | .data = &sysctl_hugetlb_shm_group, | |
5037 | .maxlen = sizeof(gid_t), | |
5038 | .mode = 0644, | |
5039 | .proc_handler = proc_dointvec, | |
5040 | }, | |
5041 | { | |
5042 | .procname = "nr_overcommit_hugepages", | |
5043 | .data = NULL, | |
5044 | .maxlen = sizeof(unsigned long), | |
5045 | .mode = 0644, | |
5046 | .proc_handler = hugetlb_overcommit_handler, | |
5047 | }, | |
5048 | { } | |
5049 | }; | |
5050 | ||
5051 | static void hugetlb_sysctl_init(void) | |
5052 | { | |
5053 | register_sysctl_init("vm", hugetlb_table); | |
5054 | } | |
1da177e4 LT |
5055 | #endif /* CONFIG_SYSCTL */ |
5056 | ||
e1759c21 | 5057 | void hugetlb_report_meminfo(struct seq_file *m) |
1da177e4 | 5058 | { |
fcb2b0c5 RG |
5059 | struct hstate *h; |
5060 | unsigned long total = 0; | |
5061 | ||
457c1b27 NA |
5062 | if (!hugepages_supported()) |
5063 | return; | |
fcb2b0c5 RG |
5064 | |
5065 | for_each_hstate(h) { | |
5066 | unsigned long count = h->nr_huge_pages; | |
5067 | ||
aca78307 | 5068 | total += huge_page_size(h) * count; |
fcb2b0c5 RG |
5069 | |
5070 | if (h == &default_hstate) | |
5071 | seq_printf(m, | |
5072 | "HugePages_Total: %5lu\n" | |
5073 | "HugePages_Free: %5lu\n" | |
5074 | "HugePages_Rsvd: %5lu\n" | |
5075 | "HugePages_Surp: %5lu\n" | |
5076 | "Hugepagesize: %8lu kB\n", | |
5077 | count, | |
5078 | h->free_huge_pages, | |
5079 | h->resv_huge_pages, | |
5080 | h->surplus_huge_pages, | |
aca78307 | 5081 | huge_page_size(h) / SZ_1K); |
fcb2b0c5 RG |
5082 | } |
5083 | ||
aca78307 | 5084 | seq_printf(m, "Hugetlb: %8lu kB\n", total / SZ_1K); |
1da177e4 LT |
5085 | } |
5086 | ||
7981593b | 5087 | int hugetlb_report_node_meminfo(char *buf, int len, int nid) |
1da177e4 | 5088 | { |
a5516438 | 5089 | struct hstate *h = &default_hstate; |
7981593b | 5090 | |
457c1b27 NA |
5091 | if (!hugepages_supported()) |
5092 | return 0; | |
7981593b JP |
5093 | |
5094 | return sysfs_emit_at(buf, len, | |
5095 | "Node %d HugePages_Total: %5u\n" | |
5096 | "Node %d HugePages_Free: %5u\n" | |
5097 | "Node %d HugePages_Surp: %5u\n", | |
5098 | nid, h->nr_huge_pages_node[nid], | |
5099 | nid, h->free_huge_pages_node[nid], | |
5100 | nid, h->surplus_huge_pages_node[nid]); | |
1da177e4 LT |
5101 | } |
5102 | ||
dcadcf1c | 5103 | void hugetlb_show_meminfo_node(int nid) |
949f7ec5 DR |
5104 | { |
5105 | struct hstate *h; | |
949f7ec5 | 5106 | |
457c1b27 NA |
5107 | if (!hugepages_supported()) |
5108 | return; | |
5109 | ||
dcadcf1c GL |
5110 | for_each_hstate(h) |
5111 | printk("Node %d hugepages_total=%u hugepages_free=%u hugepages_surp=%u hugepages_size=%lukB\n", | |
5112 | nid, | |
5113 | h->nr_huge_pages_node[nid], | |
5114 | h->free_huge_pages_node[nid], | |
5115 | h->surplus_huge_pages_node[nid], | |
5116 | huge_page_size(h) / SZ_1K); | |
949f7ec5 DR |
5117 | } |
5118 | ||
5d317b2b NH |
5119 | void hugetlb_report_usage(struct seq_file *m, struct mm_struct *mm) |
5120 | { | |
5121 | seq_printf(m, "HugetlbPages:\t%8lu kB\n", | |
6c1aa2d3 | 5122 | K(atomic_long_read(&mm->hugetlb_usage))); |
5d317b2b NH |
5123 | } |
5124 | ||
1da177e4 LT |
5125 | /* Return the number pages of memory we physically have, in PAGE_SIZE units. */ |
5126 | unsigned long hugetlb_total_pages(void) | |
5127 | { | |
d0028588 WL |
5128 | struct hstate *h; |
5129 | unsigned long nr_total_pages = 0; | |
5130 | ||
5131 | for_each_hstate(h) | |
5132 | nr_total_pages += h->nr_huge_pages * pages_per_huge_page(h); | |
5133 | return nr_total_pages; | |
1da177e4 | 5134 | } |
1da177e4 | 5135 | |
a5516438 | 5136 | static int hugetlb_acct_memory(struct hstate *h, long delta) |
fc1b8a73 MG |
5137 | { |
5138 | int ret = -ENOMEM; | |
5139 | ||
0aa7f354 ML |
5140 | if (!delta) |
5141 | return 0; | |
5142 | ||
db71ef79 | 5143 | spin_lock_irq(&hugetlb_lock); |
fc1b8a73 MG |
5144 | /* |
5145 | * When cpuset is configured, it breaks the strict hugetlb page | |
5146 | * reservation as the accounting is done on a global variable. Such | |
5147 | * reservation is completely rubbish in the presence of cpuset because | |
5148 | * the reservation is not checked against page availability for the | |
5149 | * current cpuset. Application can still potentially OOM'ed by kernel | |
5150 | * with lack of free htlb page in cpuset that the task is in. | |
5151 | * Attempt to enforce strict accounting with cpuset is almost | |
5152 | * impossible (or too ugly) because cpuset is too fluid that | |
5153 | * task or memory node can be dynamically moved between cpusets. | |
5154 | * | |
5155 | * The change of semantics for shared hugetlb mapping with cpuset is | |
5156 | * undesirable. However, in order to preserve some of the semantics, | |
5157 | * we fall back to check against current free page availability as | |
5158 | * a best attempt and hopefully to minimize the impact of changing | |
5159 | * semantics that cpuset has. | |
8ca39e68 MS |
5160 | * |
5161 | * Apart from cpuset, we also have memory policy mechanism that | |
5162 | * also determines from which node the kernel will allocate memory | |
5163 | * in a NUMA system. So similar to cpuset, we also should consider | |
5164 | * the memory policy of the current task. Similar to the description | |
5165 | * above. | |
fc1b8a73 MG |
5166 | */ |
5167 | if (delta > 0) { | |
a5516438 | 5168 | if (gather_surplus_pages(h, delta) < 0) |
fc1b8a73 MG |
5169 | goto out; |
5170 | ||
8ca39e68 | 5171 | if (delta > allowed_mems_nr(h)) { |
a5516438 | 5172 | return_unused_surplus_pages(h, delta); |
fc1b8a73 MG |
5173 | goto out; |
5174 | } | |
5175 | } | |
5176 | ||
5177 | ret = 0; | |
5178 | if (delta < 0) | |
a5516438 | 5179 | return_unused_surplus_pages(h, (unsigned long) -delta); |
fc1b8a73 MG |
5180 | |
5181 | out: | |
db71ef79 | 5182 | spin_unlock_irq(&hugetlb_lock); |
fc1b8a73 MG |
5183 | return ret; |
5184 | } | |
5185 | ||
84afd99b AW |
5186 | static void hugetlb_vm_op_open(struct vm_area_struct *vma) |
5187 | { | |
f522c3ac | 5188 | struct resv_map *resv = vma_resv_map(vma); |
84afd99b AW |
5189 | |
5190 | /* | |
612b8a31 | 5191 | * HPAGE_RESV_OWNER indicates a private mapping. |
84afd99b AW |
5192 | * This new VMA should share its siblings reservation map if present. |
5193 | * The VMA will only ever have a valid reservation map pointer where | |
5194 | * it is being copied for another still existing VMA. As that VMA | |
25985edc | 5195 | * has a reference to the reservation map it cannot disappear until |
84afd99b AW |
5196 | * after this open call completes. It is therefore safe to take a |
5197 | * new reference here without additional locking. | |
5198 | */ | |
09a26e83 MK |
5199 | if (resv && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { |
5200 | resv_map_dup_hugetlb_cgroup_uncharge_info(resv); | |
f522c3ac | 5201 | kref_get(&resv->refs); |
09a26e83 | 5202 | } |
8d9bfb26 | 5203 | |
131a79b4 MK |
5204 | /* |
5205 | * vma_lock structure for sharable mappings is vma specific. | |
612b8a31 MK |
5206 | * Clear old pointer (if copied via vm_area_dup) and allocate |
5207 | * new structure. Before clearing, make sure vma_lock is not | |
5208 | * for this vma. | |
131a79b4 MK |
5209 | */ |
5210 | if (vma->vm_flags & VM_MAYSHARE) { | |
612b8a31 MK |
5211 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; |
5212 | ||
5213 | if (vma_lock) { | |
5214 | if (vma_lock->vma != vma) { | |
5215 | vma->vm_private_data = NULL; | |
5216 | hugetlb_vma_lock_alloc(vma); | |
5217 | } else | |
5218 | pr_warn("HugeTLB: vma_lock already exists in %s.\n", __func__); | |
5219 | } else | |
5220 | hugetlb_vma_lock_alloc(vma); | |
131a79b4 | 5221 | } |
84afd99b AW |
5222 | } |
5223 | ||
a1e78772 MG |
5224 | static void hugetlb_vm_op_close(struct vm_area_struct *vma) |
5225 | { | |
a5516438 | 5226 | struct hstate *h = hstate_vma(vma); |
8d9bfb26 | 5227 | struct resv_map *resv; |
90481622 | 5228 | struct hugepage_subpool *spool = subpool_vma(vma); |
4e35f483 | 5229 | unsigned long reserve, start, end; |
1c5ecae3 | 5230 | long gbl_reserve; |
84afd99b | 5231 | |
8d9bfb26 MK |
5232 | hugetlb_vma_lock_free(vma); |
5233 | ||
5234 | resv = vma_resv_map(vma); | |
4e35f483 JK |
5235 | if (!resv || !is_vma_resv_set(vma, HPAGE_RESV_OWNER)) |
5236 | return; | |
84afd99b | 5237 | |
4e35f483 JK |
5238 | start = vma_hugecache_offset(h, vma, vma->vm_start); |
5239 | end = vma_hugecache_offset(h, vma, vma->vm_end); | |
84afd99b | 5240 | |
4e35f483 | 5241 | reserve = (end - start) - region_count(resv, start, end); |
e9fe92ae | 5242 | hugetlb_cgroup_uncharge_counter(resv, start, end); |
4e35f483 | 5243 | if (reserve) { |
1c5ecae3 MK |
5244 | /* |
5245 | * Decrement reserve counts. The global reserve count may be | |
5246 | * adjusted if the subpool has a minimum size. | |
5247 | */ | |
5248 | gbl_reserve = hugepage_subpool_put_pages(spool, reserve); | |
5249 | hugetlb_acct_memory(h, -gbl_reserve); | |
84afd99b | 5250 | } |
e9fe92ae MA |
5251 | |
5252 | kref_put(&resv->refs, resv_map_release); | |
a1e78772 MG |
5253 | } |
5254 | ||
31383c68 DW |
5255 | static int hugetlb_vm_op_split(struct vm_area_struct *vma, unsigned long addr) |
5256 | { | |
5257 | if (addr & ~(huge_page_mask(hstate_vma(vma)))) | |
5258 | return -EINVAL; | |
b30c14cd JH |
5259 | |
5260 | /* | |
5261 | * PMD sharing is only possible for PUD_SIZE-aligned address ranges | |
5262 | * in HugeTLB VMAs. If we will lose PUD_SIZE alignment due to this | |
5263 | * split, unshare PMDs in the PUD_SIZE interval surrounding addr now. | |
5264 | */ | |
5265 | if (addr & ~PUD_MASK) { | |
5266 | /* | |
5267 | * hugetlb_vm_op_split is called right before we attempt to | |
5268 | * split the VMA. We will need to unshare PMDs in the old and | |
5269 | * new VMAs, so let's unshare before we split. | |
5270 | */ | |
5271 | unsigned long floor = addr & PUD_MASK; | |
5272 | unsigned long ceil = floor + PUD_SIZE; | |
5273 | ||
5274 | if (floor >= vma->vm_start && ceil <= vma->vm_end) | |
5275 | hugetlb_unshare_pmds(vma, floor, ceil); | |
5276 | } | |
5277 | ||
31383c68 DW |
5278 | return 0; |
5279 | } | |
5280 | ||
05ea8860 DW |
5281 | static unsigned long hugetlb_vm_op_pagesize(struct vm_area_struct *vma) |
5282 | { | |
aca78307 | 5283 | return huge_page_size(hstate_vma(vma)); |
05ea8860 DW |
5284 | } |
5285 | ||
1da177e4 LT |
5286 | /* |
5287 | * We cannot handle pagefaults against hugetlb pages at all. They cause | |
5288 | * handle_mm_fault() to try to instantiate regular-sized pages in the | |
6c26d310 | 5289 | * hugepage VMA. do_page_fault() is supposed to trap this, so BUG is we get |
1da177e4 LT |
5290 | * this far. |
5291 | */ | |
b3ec9f33 | 5292 | static vm_fault_t hugetlb_vm_op_fault(struct vm_fault *vmf) |
1da177e4 LT |
5293 | { |
5294 | BUG(); | |
d0217ac0 | 5295 | return 0; |
1da177e4 LT |
5296 | } |
5297 | ||
eec3636a JC |
5298 | /* |
5299 | * When a new function is introduced to vm_operations_struct and added | |
5300 | * to hugetlb_vm_ops, please consider adding the function to shm_vm_ops. | |
5301 | * This is because under System V memory model, mappings created via | |
5302 | * shmget/shmat with "huge page" specified are backed by hugetlbfs files, | |
5303 | * their original vm_ops are overwritten with shm_vm_ops. | |
5304 | */ | |
f0f37e2f | 5305 | const struct vm_operations_struct hugetlb_vm_ops = { |
d0217ac0 | 5306 | .fault = hugetlb_vm_op_fault, |
84afd99b | 5307 | .open = hugetlb_vm_op_open, |
a1e78772 | 5308 | .close = hugetlb_vm_op_close, |
dd3b614f | 5309 | .may_split = hugetlb_vm_op_split, |
05ea8860 | 5310 | .pagesize = hugetlb_vm_op_pagesize, |
1da177e4 LT |
5311 | }; |
5312 | ||
1e8f889b DG |
5313 | static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page, |
5314 | int writable) | |
63551ae0 DG |
5315 | { |
5316 | pte_t entry; | |
79c1c594 | 5317 | unsigned int shift = huge_page_shift(hstate_vma(vma)); |
63551ae0 | 5318 | |
1e8f889b | 5319 | if (writable) { |
106c992a GS |
5320 | entry = huge_pte_mkwrite(huge_pte_mkdirty(mk_huge_pte(page, |
5321 | vma->vm_page_prot))); | |
63551ae0 | 5322 | } else { |
106c992a GS |
5323 | entry = huge_pte_wrprotect(mk_huge_pte(page, |
5324 | vma->vm_page_prot)); | |
63551ae0 DG |
5325 | } |
5326 | entry = pte_mkyoung(entry); | |
79c1c594 | 5327 | entry = arch_make_huge_pte(entry, shift, vma->vm_flags); |
63551ae0 DG |
5328 | |
5329 | return entry; | |
5330 | } | |
5331 | ||
1e8f889b DG |
5332 | static void set_huge_ptep_writable(struct vm_area_struct *vma, |
5333 | unsigned long address, pte_t *ptep) | |
5334 | { | |
5335 | pte_t entry; | |
5336 | ||
106c992a | 5337 | entry = huge_pte_mkwrite(huge_pte_mkdirty(huge_ptep_get(ptep))); |
32f84528 | 5338 | if (huge_ptep_set_access_flags(vma, address, ptep, entry, 1)) |
4b3073e1 | 5339 | update_mmu_cache(vma, address, ptep); |
1e8f889b DG |
5340 | } |
5341 | ||
d5ed7444 | 5342 | bool is_hugetlb_entry_migration(pte_t pte) |
4a705fef NH |
5343 | { |
5344 | swp_entry_t swp; | |
5345 | ||
5346 | if (huge_pte_none(pte) || pte_present(pte)) | |
d5ed7444 | 5347 | return false; |
4a705fef | 5348 | swp = pte_to_swp_entry(pte); |
d79d176a | 5349 | if (is_migration_entry(swp)) |
d5ed7444 | 5350 | return true; |
4a705fef | 5351 | else |
d5ed7444 | 5352 | return false; |
4a705fef NH |
5353 | } |
5354 | ||
52526ca7 | 5355 | bool is_hugetlb_entry_hwpoisoned(pte_t pte) |
4a705fef NH |
5356 | { |
5357 | swp_entry_t swp; | |
5358 | ||
5359 | if (huge_pte_none(pte) || pte_present(pte)) | |
3e5c3600 | 5360 | return false; |
4a705fef | 5361 | swp = pte_to_swp_entry(pte); |
d79d176a | 5362 | if (is_hwpoison_entry(swp)) |
3e5c3600 | 5363 | return true; |
4a705fef | 5364 | else |
3e5c3600 | 5365 | return false; |
4a705fef | 5366 | } |
1e8f889b | 5367 | |
4eae4efa | 5368 | static void |
ea4c353d | 5369 | hugetlb_install_folio(struct vm_area_struct *vma, pte_t *ptep, unsigned long addr, |
935d4f0c | 5370 | struct folio *new_folio, pte_t old, unsigned long sz) |
4eae4efa | 5371 | { |
5a2f8d22 PX |
5372 | pte_t newpte = make_huge_pte(vma, &new_folio->page, 1); |
5373 | ||
ea4c353d | 5374 | __folio_mark_uptodate(new_folio); |
9d5fafd5 | 5375 | hugetlb_add_new_anon_rmap(new_folio, vma, addr); |
5a2f8d22 PX |
5376 | if (userfaultfd_wp(vma) && huge_pte_uffd_wp(old)) |
5377 | newpte = huge_pte_mkuffd_wp(newpte); | |
935d4f0c | 5378 | set_huge_pte_at(vma->vm_mm, addr, ptep, newpte, sz); |
4eae4efa | 5379 | hugetlb_count_add(pages_per_huge_page(hstate_vma(vma)), vma->vm_mm); |
ea4c353d | 5380 | folio_set_hugetlb_migratable(new_folio); |
4eae4efa PX |
5381 | } |
5382 | ||
63551ae0 | 5383 | int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, |
bc70fbf2 PX |
5384 | struct vm_area_struct *dst_vma, |
5385 | struct vm_area_struct *src_vma) | |
63551ae0 | 5386 | { |
3aa4ed80 | 5387 | pte_t *src_pte, *dst_pte, entry; |
ad27ce20 | 5388 | struct folio *pte_folio; |
1c59827d | 5389 | unsigned long addr; |
bc70fbf2 PX |
5390 | bool cow = is_cow_mapping(src_vma->vm_flags); |
5391 | struct hstate *h = hstate_vma(src_vma); | |
a5516438 | 5392 | unsigned long sz = huge_page_size(h); |
4eae4efa | 5393 | unsigned long npages = pages_per_huge_page(h); |
ac46d4f3 | 5394 | struct mmu_notifier_range range; |
e95a9851 | 5395 | unsigned long last_addr_mask; |
e8569dd2 | 5396 | int ret = 0; |
1e8f889b | 5397 | |
ac46d4f3 | 5398 | if (cow) { |
7d4a8be0 | 5399 | mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, src, |
bc70fbf2 PX |
5400 | src_vma->vm_start, |
5401 | src_vma->vm_end); | |
ac46d4f3 | 5402 | mmu_notifier_invalidate_range_start(&range); |
e727bfd5 | 5403 | vma_assert_write_locked(src_vma); |
623a1ddf | 5404 | raw_write_seqcount_begin(&src->write_protect_seq); |
40549ba8 MK |
5405 | } else { |
5406 | /* | |
5407 | * For shared mappings the vma lock must be held before | |
9c67a207 | 5408 | * calling hugetlb_walk() in the src vma. Otherwise, the |
40549ba8 MK |
5409 | * returned ptep could go away if part of a shared pmd and |
5410 | * another thread calls huge_pmd_unshare. | |
5411 | */ | |
5412 | hugetlb_vma_lock_read(src_vma); | |
ac46d4f3 | 5413 | } |
e8569dd2 | 5414 | |
e95a9851 | 5415 | last_addr_mask = hugetlb_mask_last_page(h); |
bc70fbf2 | 5416 | for (addr = src_vma->vm_start; addr < src_vma->vm_end; addr += sz) { |
cb900f41 | 5417 | spinlock_t *src_ptl, *dst_ptl; |
9c67a207 | 5418 | src_pte = hugetlb_walk(src_vma, addr, sz); |
e95a9851 MK |
5419 | if (!src_pte) { |
5420 | addr |= last_addr_mask; | |
c74df32c | 5421 | continue; |
e95a9851 | 5422 | } |
bc70fbf2 | 5423 | dst_pte = huge_pte_alloc(dst, dst_vma, addr, sz); |
e8569dd2 AS |
5424 | if (!dst_pte) { |
5425 | ret = -ENOMEM; | |
5426 | break; | |
5427 | } | |
c5c99429 | 5428 | |
5e41540c MK |
5429 | /* |
5430 | * If the pagetables are shared don't copy or take references. | |
5e41540c | 5431 | * |
3aa4ed80 | 5432 | * dst_pte == src_pte is the common case of src/dest sharing. |
5e41540c | 5433 | * However, src could have 'unshared' and dst shares with |
3aa4ed80 ML |
5434 | * another vma. So page_count of ptep page is checked instead |
5435 | * to reliably determine whether pte is shared. | |
5e41540c | 5436 | */ |
3aa4ed80 | 5437 | if (page_count(virt_to_page(dst_pte)) > 1) { |
e95a9851 | 5438 | addr |= last_addr_mask; |
c5c99429 | 5439 | continue; |
e95a9851 | 5440 | } |
c5c99429 | 5441 | |
cb900f41 KS |
5442 | dst_ptl = huge_pte_lock(h, dst, dst_pte); |
5443 | src_ptl = huge_pte_lockptr(h, src, src_pte); | |
5444 | spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING); | |
4a705fef | 5445 | entry = huge_ptep_get(src_pte); |
4eae4efa | 5446 | again: |
3aa4ed80 | 5447 | if (huge_pte_none(entry)) { |
5e41540c | 5448 | /* |
3aa4ed80 | 5449 | * Skip if src entry none. |
5e41540c | 5450 | */ |
4a705fef | 5451 | ; |
c2cb0dcc | 5452 | } else if (unlikely(is_hugetlb_entry_hwpoisoned(entry))) { |
5a2f8d22 | 5453 | if (!userfaultfd_wp(dst_vma)) |
c2cb0dcc | 5454 | entry = huge_pte_clear_uffd_wp(entry); |
935d4f0c | 5455 | set_huge_pte_at(dst, addr, dst_pte, entry, sz); |
c2cb0dcc | 5456 | } else if (unlikely(is_hugetlb_entry_migration(entry))) { |
4a705fef | 5457 | swp_entry_t swp_entry = pte_to_swp_entry(entry); |
5a2f8d22 | 5458 | bool uffd_wp = pte_swp_uffd_wp(entry); |
4a705fef | 5459 | |
6c287605 | 5460 | if (!is_readable_migration_entry(swp_entry) && cow) { |
4a705fef NH |
5461 | /* |
5462 | * COW mappings require pages in both | |
5463 | * parent and child to be set to read. | |
5464 | */ | |
4dd845b5 AP |
5465 | swp_entry = make_readable_migration_entry( |
5466 | swp_offset(swp_entry)); | |
4a705fef | 5467 | entry = swp_entry_to_pte(swp_entry); |
bc70fbf2 | 5468 | if (userfaultfd_wp(src_vma) && uffd_wp) |
5a2f8d22 | 5469 | entry = pte_swp_mkuffd_wp(entry); |
935d4f0c | 5470 | set_huge_pte_at(src, addr, src_pte, entry, sz); |
4a705fef | 5471 | } |
5a2f8d22 | 5472 | if (!userfaultfd_wp(dst_vma)) |
bc70fbf2 | 5473 | entry = huge_pte_clear_uffd_wp(entry); |
935d4f0c | 5474 | set_huge_pte_at(dst, addr, dst_pte, entry, sz); |
bc70fbf2 | 5475 | } else if (unlikely(is_pte_marker(entry))) { |
af19487f AR |
5476 | pte_marker marker = copy_pte_marker( |
5477 | pte_to_swp_entry(entry), dst_vma); | |
5478 | ||
5479 | if (marker) | |
5480 | set_huge_pte_at(dst, addr, dst_pte, | |
935d4f0c | 5481 | make_pte_marker(marker), sz); |
4a705fef | 5482 | } else { |
4eae4efa | 5483 | entry = huge_ptep_get(src_pte); |
ad27ce20 Z |
5484 | pte_folio = page_folio(pte_page(entry)); |
5485 | folio_get(pte_folio); | |
4eae4efa PX |
5486 | |
5487 | /* | |
fb3d824d DH |
5488 | * Failing to duplicate the anon rmap is a rare case |
5489 | * where we see pinned hugetlb pages while they're | |
5490 | * prone to COW. We need to do the COW earlier during | |
5491 | * fork. | |
4eae4efa PX |
5492 | * |
5493 | * When pre-allocating the page or copying data, we | |
5494 | * need to be without the pgtable locks since we could | |
5495 | * sleep during the process. | |
5496 | */ | |
ad27ce20 | 5497 | if (!folio_test_anon(pte_folio)) { |
44887f39 | 5498 | hugetlb_add_file_rmap(pte_folio); |
ebe2e35e | 5499 | } else if (hugetlb_try_dup_anon_rmap(pte_folio, src_vma)) { |
4eae4efa | 5500 | pte_t src_pte_old = entry; |
d0ce0e47 | 5501 | struct folio *new_folio; |
4eae4efa PX |
5502 | |
5503 | spin_unlock(src_ptl); | |
5504 | spin_unlock(dst_ptl); | |
5505 | /* Do not use reserve as it's private owned */ | |
d0ce0e47 SK |
5506 | new_folio = alloc_hugetlb_folio(dst_vma, addr, 1); |
5507 | if (IS_ERR(new_folio)) { | |
ad27ce20 | 5508 | folio_put(pte_folio); |
d0ce0e47 | 5509 | ret = PTR_ERR(new_folio); |
4eae4efa PX |
5510 | break; |
5511 | } | |
1cb9dc4b | 5512 | ret = copy_user_large_folio(new_folio, |
ad27ce20 Z |
5513 | pte_folio, |
5514 | addr, dst_vma); | |
5515 | folio_put(pte_folio); | |
1cb9dc4b LS |
5516 | if (ret) { |
5517 | folio_put(new_folio); | |
5518 | break; | |
5519 | } | |
4eae4efa | 5520 | |
d0ce0e47 | 5521 | /* Install the new hugetlb folio if src pte stable */ |
4eae4efa PX |
5522 | dst_ptl = huge_pte_lock(h, dst, dst_pte); |
5523 | src_ptl = huge_pte_lockptr(h, src, src_pte); | |
5524 | spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING); | |
5525 | entry = huge_ptep_get(src_pte); | |
5526 | if (!pte_same(src_pte_old, entry)) { | |
bc70fbf2 | 5527 | restore_reserve_on_error(h, dst_vma, addr, |
d2d7bb44 | 5528 | new_folio); |
d0ce0e47 | 5529 | folio_put(new_folio); |
3aa4ed80 | 5530 | /* huge_ptep of dst_pte won't change as in child */ |
4eae4efa PX |
5531 | goto again; |
5532 | } | |
5a2f8d22 | 5533 | hugetlb_install_folio(dst_vma, dst_pte, addr, |
935d4f0c | 5534 | new_folio, src_pte_old, sz); |
4eae4efa PX |
5535 | spin_unlock(src_ptl); |
5536 | spin_unlock(dst_ptl); | |
5537 | continue; | |
5538 | } | |
5539 | ||
34ee645e | 5540 | if (cow) { |
0f10851e JG |
5541 | /* |
5542 | * No need to notify as we are downgrading page | |
5543 | * table protection not changing it to point | |
5544 | * to a new page. | |
5545 | * | |
ee65728e | 5546 | * See Documentation/mm/mmu_notifier.rst |
0f10851e | 5547 | */ |
7f2e9525 | 5548 | huge_ptep_set_wrprotect(src, addr, src_pte); |
84894e1c | 5549 | entry = huge_pte_wrprotect(entry); |
34ee645e | 5550 | } |
4eae4efa | 5551 | |
5a2f8d22 PX |
5552 | if (!userfaultfd_wp(dst_vma)) |
5553 | entry = huge_pte_clear_uffd_wp(entry); | |
5554 | ||
935d4f0c | 5555 | set_huge_pte_at(dst, addr, dst_pte, entry, sz); |
4eae4efa | 5556 | hugetlb_count_add(npages, dst); |
1c59827d | 5557 | } |
cb900f41 KS |
5558 | spin_unlock(src_ptl); |
5559 | spin_unlock(dst_ptl); | |
63551ae0 | 5560 | } |
63551ae0 | 5561 | |
623a1ddf DH |
5562 | if (cow) { |
5563 | raw_write_seqcount_end(&src->write_protect_seq); | |
ac46d4f3 | 5564 | mmu_notifier_invalidate_range_end(&range); |
40549ba8 MK |
5565 | } else { |
5566 | hugetlb_vma_unlock_read(src_vma); | |
623a1ddf | 5567 | } |
e8569dd2 AS |
5568 | |
5569 | return ret; | |
63551ae0 DG |
5570 | } |
5571 | ||
550a7d60 | 5572 | static void move_huge_pte(struct vm_area_struct *vma, unsigned long old_addr, |
935d4f0c RR |
5573 | unsigned long new_addr, pte_t *src_pte, pte_t *dst_pte, |
5574 | unsigned long sz) | |
550a7d60 MA |
5575 | { |
5576 | struct hstate *h = hstate_vma(vma); | |
5577 | struct mm_struct *mm = vma->vm_mm; | |
550a7d60 | 5578 | spinlock_t *src_ptl, *dst_ptl; |
db110a99 | 5579 | pte_t pte; |
550a7d60 | 5580 | |
550a7d60 MA |
5581 | dst_ptl = huge_pte_lock(h, mm, dst_pte); |
5582 | src_ptl = huge_pte_lockptr(h, mm, src_pte); | |
5583 | ||
5584 | /* | |
5585 | * We don't have to worry about the ordering of src and dst ptlocks | |
8651a137 | 5586 | * because exclusive mmap_lock (or the i_mmap_lock) prevents deadlock. |
550a7d60 MA |
5587 | */ |
5588 | if (src_ptl != dst_ptl) | |
5589 | spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING); | |
5590 | ||
5591 | pte = huge_ptep_get_and_clear(mm, old_addr, src_pte); | |
935d4f0c | 5592 | set_huge_pte_at(mm, new_addr, dst_pte, pte, sz); |
550a7d60 MA |
5593 | |
5594 | if (src_ptl != dst_ptl) | |
5595 | spin_unlock(src_ptl); | |
5596 | spin_unlock(dst_ptl); | |
5597 | } | |
5598 | ||
5599 | int move_hugetlb_page_tables(struct vm_area_struct *vma, | |
5600 | struct vm_area_struct *new_vma, | |
5601 | unsigned long old_addr, unsigned long new_addr, | |
5602 | unsigned long len) | |
5603 | { | |
5604 | struct hstate *h = hstate_vma(vma); | |
5605 | struct address_space *mapping = vma->vm_file->f_mapping; | |
5606 | unsigned long sz = huge_page_size(h); | |
5607 | struct mm_struct *mm = vma->vm_mm; | |
5608 | unsigned long old_end = old_addr + len; | |
e95a9851 | 5609 | unsigned long last_addr_mask; |
550a7d60 MA |
5610 | pte_t *src_pte, *dst_pte; |
5611 | struct mmu_notifier_range range; | |
3d0b95cd | 5612 | bool shared_pmd = false; |
550a7d60 | 5613 | |
7d4a8be0 | 5614 | mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm, old_addr, |
550a7d60 MA |
5615 | old_end); |
5616 | adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end); | |
3d0b95cd BW |
5617 | /* |
5618 | * In case of shared PMDs, we should cover the maximum possible | |
5619 | * range. | |
5620 | */ | |
5621 | flush_cache_range(vma, range.start, range.end); | |
5622 | ||
550a7d60 | 5623 | mmu_notifier_invalidate_range_start(&range); |
e95a9851 | 5624 | last_addr_mask = hugetlb_mask_last_page(h); |
550a7d60 | 5625 | /* Prevent race with file truncation */ |
40549ba8 | 5626 | hugetlb_vma_lock_write(vma); |
550a7d60 MA |
5627 | i_mmap_lock_write(mapping); |
5628 | for (; old_addr < old_end; old_addr += sz, new_addr += sz) { | |
9c67a207 | 5629 | src_pte = hugetlb_walk(vma, old_addr, sz); |
e95a9851 MK |
5630 | if (!src_pte) { |
5631 | old_addr |= last_addr_mask; | |
5632 | new_addr |= last_addr_mask; | |
550a7d60 | 5633 | continue; |
e95a9851 | 5634 | } |
550a7d60 MA |
5635 | if (huge_pte_none(huge_ptep_get(src_pte))) |
5636 | continue; | |
5637 | ||
4ddb4d91 | 5638 | if (huge_pmd_unshare(mm, vma, old_addr, src_pte)) { |
3d0b95cd | 5639 | shared_pmd = true; |
4ddb4d91 MK |
5640 | old_addr |= last_addr_mask; |
5641 | new_addr |= last_addr_mask; | |
550a7d60 | 5642 | continue; |
3d0b95cd | 5643 | } |
550a7d60 MA |
5644 | |
5645 | dst_pte = huge_pte_alloc(mm, new_vma, new_addr, sz); | |
5646 | if (!dst_pte) | |
5647 | break; | |
5648 | ||
935d4f0c | 5649 | move_huge_pte(vma, old_addr, new_addr, src_pte, dst_pte, sz); |
550a7d60 | 5650 | } |
3d0b95cd BW |
5651 | |
5652 | if (shared_pmd) | |
f720b471 | 5653 | flush_hugetlb_tlb_range(vma, range.start, range.end); |
3d0b95cd | 5654 | else |
f720b471 | 5655 | flush_hugetlb_tlb_range(vma, old_end - len, old_end); |
550a7d60 | 5656 | mmu_notifier_invalidate_range_end(&range); |
13e4ad2c | 5657 | i_mmap_unlock_write(mapping); |
40549ba8 | 5658 | hugetlb_vma_unlock_write(vma); |
550a7d60 MA |
5659 | |
5660 | return len + old_addr - old_end; | |
5661 | } | |
5662 | ||
2820b0f0 RR |
5663 | void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, |
5664 | unsigned long start, unsigned long end, | |
5665 | struct page *ref_page, zap_flags_t zap_flags) | |
63551ae0 DG |
5666 | { |
5667 | struct mm_struct *mm = vma->vm_mm; | |
5668 | unsigned long address; | |
c7546f8f | 5669 | pte_t *ptep; |
63551ae0 | 5670 | pte_t pte; |
cb900f41 | 5671 | spinlock_t *ptl; |
63551ae0 | 5672 | struct page *page; |
a5516438 AK |
5673 | struct hstate *h = hstate_vma(vma); |
5674 | unsigned long sz = huge_page_size(h); | |
df7a6d1f | 5675 | bool adjust_reservation = false; |
e95a9851 | 5676 | unsigned long last_addr_mask; |
a4a118f2 | 5677 | bool force_flush = false; |
a5516438 | 5678 | |
63551ae0 | 5679 | WARN_ON(!is_vm_hugetlb_page(vma)); |
a5516438 AK |
5680 | BUG_ON(start & ~huge_page_mask(h)); |
5681 | BUG_ON(end & ~huge_page_mask(h)); | |
63551ae0 | 5682 | |
07e32661 AK |
5683 | /* |
5684 | * This is a hugetlb vma, all the pte entries should point | |
5685 | * to huge page. | |
5686 | */ | |
ed6a7935 | 5687 | tlb_change_page_size(tlb, sz); |
24669e58 | 5688 | tlb_start_vma(tlb, vma); |
dff11abe | 5689 | |
e95a9851 | 5690 | last_addr_mask = hugetlb_mask_last_page(h); |
569f48b8 | 5691 | address = start; |
569f48b8 | 5692 | for (; address < end; address += sz) { |
9c67a207 | 5693 | ptep = hugetlb_walk(vma, address, sz); |
e95a9851 MK |
5694 | if (!ptep) { |
5695 | address |= last_addr_mask; | |
c7546f8f | 5696 | continue; |
e95a9851 | 5697 | } |
c7546f8f | 5698 | |
cb900f41 | 5699 | ptl = huge_pte_lock(h, mm, ptep); |
4ddb4d91 | 5700 | if (huge_pmd_unshare(mm, vma, address, ptep)) { |
31d49da5 | 5701 | spin_unlock(ptl); |
a4a118f2 NA |
5702 | tlb_flush_pmd_range(tlb, address & PUD_MASK, PUD_SIZE); |
5703 | force_flush = true; | |
4ddb4d91 | 5704 | address |= last_addr_mask; |
31d49da5 AK |
5705 | continue; |
5706 | } | |
39dde65c | 5707 | |
6629326b | 5708 | pte = huge_ptep_get(ptep); |
31d49da5 AK |
5709 | if (huge_pte_none(pte)) { |
5710 | spin_unlock(ptl); | |
5711 | continue; | |
5712 | } | |
6629326b HD |
5713 | |
5714 | /* | |
9fbc1f63 NH |
5715 | * Migrating hugepage or HWPoisoned hugepage is already |
5716 | * unmapped and its refcount is dropped, so just clear pte here. | |
6629326b | 5717 | */ |
9fbc1f63 | 5718 | if (unlikely(!pte_present(pte))) { |
05e90bd0 PX |
5719 | /* |
5720 | * If the pte was wr-protected by uffd-wp in any of the | |
5721 | * swap forms, meanwhile the caller does not want to | |
5722 | * drop the uffd-wp bit in this zap, then replace the | |
5723 | * pte with a marker. | |
5724 | */ | |
5725 | if (pte_swp_uffd_wp_any(pte) && | |
5726 | !(zap_flags & ZAP_FLAG_DROP_MARKER)) | |
5727 | set_huge_pte_at(mm, address, ptep, | |
935d4f0c RR |
5728 | make_pte_marker(PTE_MARKER_UFFD_WP), |
5729 | sz); | |
05e90bd0 PX |
5730 | else |
5731 | huge_pte_clear(mm, address, ptep, sz); | |
31d49da5 AK |
5732 | spin_unlock(ptl); |
5733 | continue; | |
8c4894c6 | 5734 | } |
6629326b HD |
5735 | |
5736 | page = pte_page(pte); | |
04f2cbe3 MG |
5737 | /* |
5738 | * If a reference page is supplied, it is because a specific | |
5739 | * page is being unmapped, not a range. Ensure the page we | |
5740 | * are about to unmap is the actual page of interest. | |
5741 | */ | |
5742 | if (ref_page) { | |
31d49da5 AK |
5743 | if (page != ref_page) { |
5744 | spin_unlock(ptl); | |
5745 | continue; | |
5746 | } | |
04f2cbe3 MG |
5747 | /* |
5748 | * Mark the VMA as having unmapped its page so that | |
5749 | * future faults in this VMA will fail rather than | |
5750 | * looking like data was lost | |
5751 | */ | |
5752 | set_vma_resv_flags(vma, HPAGE_RESV_UNMAPPED); | |
5753 | } | |
5754 | ||
c7546f8f | 5755 | pte = huge_ptep_get_and_clear(mm, address, ptep); |
b528e4b6 | 5756 | tlb_remove_huge_tlb_entry(h, tlb, ptep, address); |
106c992a | 5757 | if (huge_pte_dirty(pte)) |
6649a386 | 5758 | set_page_dirty(page); |
05e90bd0 PX |
5759 | /* Leave a uffd-wp pte marker if needed */ |
5760 | if (huge_pte_uffd_wp(pte) && | |
5761 | !(zap_flags & ZAP_FLAG_DROP_MARKER)) | |
5762 | set_huge_pte_at(mm, address, ptep, | |
935d4f0c RR |
5763 | make_pte_marker(PTE_MARKER_UFFD_WP), |
5764 | sz); | |
5d317b2b | 5765 | hugetlb_count_sub(pages_per_huge_page(h), mm); |
e135826b | 5766 | hugetlb_remove_rmap(page_folio(page)); |
31d49da5 | 5767 | |
df7a6d1f BL |
5768 | /* |
5769 | * Restore the reservation for anonymous page, otherwise the | |
5770 | * backing page could be stolen by someone. | |
5771 | * If there we are freeing a surplus, do not set the restore | |
5772 | * reservation bit. | |
5773 | */ | |
5774 | if (!h->surplus_huge_pages && __vma_private_lock(vma) && | |
5775 | folio_test_anon(page_folio(page))) { | |
5776 | folio_set_hugetlb_restore_reserve(page_folio(page)); | |
5777 | /* Reservation to be adjusted after the spin lock */ | |
5778 | adjust_reservation = true; | |
5779 | } | |
5780 | ||
cb900f41 | 5781 | spin_unlock(ptl); |
df7a6d1f BL |
5782 | |
5783 | /* | |
5784 | * Adjust the reservation for the region that will have the | |
5785 | * reserve restored. Keep in mind that vma_needs_reservation() changes | |
5786 | * resv->adds_in_progress if it succeeds. If this is not done, | |
5787 | * do_exit() will not see it, and will keep the reservation | |
5788 | * forever. | |
5789 | */ | |
5790 | if (adjust_reservation && vma_needs_reservation(h, vma, address)) | |
5791 | vma_add_reservation(h, vma, address); | |
5792 | ||
e77b0852 | 5793 | tlb_remove_page_size(tlb, page, huge_page_size(h)); |
31d49da5 AK |
5794 | /* |
5795 | * Bail out after unmapping reference page if supplied | |
5796 | */ | |
5797 | if (ref_page) | |
5798 | break; | |
fe1668ae | 5799 | } |
24669e58 | 5800 | tlb_end_vma(tlb, vma); |
a4a118f2 NA |
5801 | |
5802 | /* | |
5803 | * If we unshared PMDs, the TLB flush was not recorded in mmu_gather. We | |
5804 | * could defer the flush until now, since by holding i_mmap_rwsem we | |
5805 | * guaranteed that the last refernece would not be dropped. But we must | |
5806 | * do the flushing before we return, as otherwise i_mmap_rwsem will be | |
5807 | * dropped and the last reference to the shared PMDs page might be | |
5808 | * dropped as well. | |
5809 | * | |
5810 | * In theory we could defer the freeing of the PMD pages as well, but | |
5811 | * huge_pmd_unshare() relies on the exact page_count for the PMD page to | |
5812 | * detect sharing, so we cannot defer the release of the page either. | |
5813 | * Instead, do flush now. | |
5814 | */ | |
5815 | if (force_flush) | |
5816 | tlb_flush_mmu_tlbonly(tlb); | |
1da177e4 | 5817 | } |
63551ae0 | 5818 | |
2820b0f0 RR |
5819 | void __hugetlb_zap_begin(struct vm_area_struct *vma, |
5820 | unsigned long *start, unsigned long *end) | |
d833352a | 5821 | { |
2820b0f0 RR |
5822 | if (!vma->vm_file) /* hugetlbfs_file_mmap error */ |
5823 | return; | |
5824 | ||
5825 | adjust_range_if_pmd_sharing_possible(vma, start, end); | |
131a79b4 | 5826 | hugetlb_vma_lock_write(vma); |
2820b0f0 RR |
5827 | if (vma->vm_file) |
5828 | i_mmap_lock_write(vma->vm_file->f_mapping); | |
5829 | } | |
131a79b4 | 5830 | |
2820b0f0 RR |
5831 | void __hugetlb_zap_end(struct vm_area_struct *vma, |
5832 | struct zap_details *details) | |
5833 | { | |
5834 | zap_flags_t zap_flags = details ? details->zap_flags : 0; | |
131a79b4 | 5835 | |
2820b0f0 RR |
5836 | if (!vma->vm_file) /* hugetlbfs_file_mmap error */ |
5837 | return; | |
d833352a | 5838 | |
04ada095 MK |
5839 | if (zap_flags & ZAP_FLAG_UNMAP) { /* final unmap */ |
5840 | /* | |
5841 | * Unlock and free the vma lock before releasing i_mmap_rwsem. | |
5842 | * When the vma_lock is freed, this makes the vma ineligible | |
5843 | * for pmd sharing. And, i_mmap_rwsem is required to set up | |
5844 | * pmd sharing. This is important as page tables for this | |
5845 | * unmapped range will be asynchrously deleted. If the page | |
5846 | * tables are shared, there will be issues when accessed by | |
5847 | * someone else. | |
5848 | */ | |
5849 | __hugetlb_vma_unlock_write_free(vma); | |
04ada095 | 5850 | } else { |
04ada095 MK |
5851 | hugetlb_vma_unlock_write(vma); |
5852 | } | |
2820b0f0 RR |
5853 | |
5854 | if (vma->vm_file) | |
5855 | i_mmap_unlock_write(vma->vm_file->f_mapping); | |
d833352a MG |
5856 | } |
5857 | ||
502717f4 | 5858 | void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, |
05e90bd0 PX |
5859 | unsigned long end, struct page *ref_page, |
5860 | zap_flags_t zap_flags) | |
502717f4 | 5861 | { |
369258ce | 5862 | struct mmu_notifier_range range; |
24669e58 | 5863 | struct mmu_gather tlb; |
dff11abe | 5864 | |
7d4a8be0 | 5865 | mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma->vm_mm, |
369258ce MK |
5866 | start, end); |
5867 | adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end); | |
5868 | mmu_notifier_invalidate_range_start(&range); | |
a72afd87 | 5869 | tlb_gather_mmu(&tlb, vma->vm_mm); |
369258ce | 5870 | |
05e90bd0 | 5871 | __unmap_hugepage_range(&tlb, vma, start, end, ref_page, zap_flags); |
369258ce MK |
5872 | |
5873 | mmu_notifier_invalidate_range_end(&range); | |
ae8eba8b | 5874 | tlb_finish_mmu(&tlb); |
502717f4 CK |
5875 | } |
5876 | ||
04f2cbe3 MG |
5877 | /* |
5878 | * This is called when the original mapper is failing to COW a MAP_PRIVATE | |
578b7725 | 5879 | * mapping it owns the reserve page for. The intention is to unmap the page |
04f2cbe3 MG |
5880 | * from other VMAs and let the children be SIGKILLed if they are faulting the |
5881 | * same region. | |
5882 | */ | |
2f4612af DB |
5883 | static void unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma, |
5884 | struct page *page, unsigned long address) | |
04f2cbe3 | 5885 | { |
7526674d | 5886 | struct hstate *h = hstate_vma(vma); |
04f2cbe3 MG |
5887 | struct vm_area_struct *iter_vma; |
5888 | struct address_space *mapping; | |
04f2cbe3 MG |
5889 | pgoff_t pgoff; |
5890 | ||
5891 | /* | |
5892 | * vm_pgoff is in PAGE_SIZE units, hence the different calculation | |
5893 | * from page cache lookup which is in HPAGE_SIZE units. | |
5894 | */ | |
7526674d | 5895 | address = address & huge_page_mask(h); |
36e4f20a MH |
5896 | pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) + |
5897 | vma->vm_pgoff; | |
93c76a3d | 5898 | mapping = vma->vm_file->f_mapping; |
04f2cbe3 | 5899 | |
4eb2b1dc MG |
5900 | /* |
5901 | * Take the mapping lock for the duration of the table walk. As | |
5902 | * this mapping should be shared between all the VMAs, | |
5903 | * __unmap_hugepage_range() is called as the lock is already held | |
5904 | */ | |
83cde9e8 | 5905 | i_mmap_lock_write(mapping); |
6b2dbba8 | 5906 | vma_interval_tree_foreach(iter_vma, &mapping->i_mmap, pgoff, pgoff) { |
04f2cbe3 MG |
5907 | /* Do not unmap the current VMA */ |
5908 | if (iter_vma == vma) | |
5909 | continue; | |
5910 | ||
2f84a899 MG |
5911 | /* |
5912 | * Shared VMAs have their own reserves and do not affect | |
5913 | * MAP_PRIVATE accounting but it is possible that a shared | |
5914 | * VMA is using the same page so check and skip such VMAs. | |
5915 | */ | |
5916 | if (iter_vma->vm_flags & VM_MAYSHARE) | |
5917 | continue; | |
5918 | ||
04f2cbe3 MG |
5919 | /* |
5920 | * Unmap the page from other VMAs without their own reserves. | |
5921 | * They get marked to be SIGKILLed if they fault in these | |
5922 | * areas. This is because a future no-page fault on this VMA | |
5923 | * could insert a zeroed page instead of the data existing | |
5924 | * from the time of fork. This would look like data corruption | |
5925 | */ | |
5926 | if (!is_vma_resv_set(iter_vma, HPAGE_RESV_OWNER)) | |
24669e58 | 5927 | unmap_hugepage_range(iter_vma, address, |
05e90bd0 | 5928 | address + huge_page_size(h), page, 0); |
04f2cbe3 | 5929 | } |
83cde9e8 | 5930 | i_mmap_unlock_write(mapping); |
04f2cbe3 MG |
5931 | } |
5932 | ||
0fe6e20b | 5933 | /* |
c89357e2 | 5934 | * hugetlb_wp() should be called with page lock of the original hugepage held. |
aa6d2e8c | 5935 | * Called with hugetlb_fault_mutex_table held and pte_page locked so we |
ef009b25 MH |
5936 | * cannot race with other handlers or page migration. |
5937 | * Keep the pte_same checks anyway to make transition from the mutex easier. | |
0fe6e20b | 5938 | */ |
c89357e2 DH |
5939 | static vm_fault_t hugetlb_wp(struct mm_struct *mm, struct vm_area_struct *vma, |
5940 | unsigned long address, pte_t *ptep, unsigned int flags, | |
9acad7ba VMO |
5941 | struct folio *pagecache_folio, spinlock_t *ptl, |
5942 | struct vm_fault *vmf) | |
1e8f889b | 5943 | { |
c89357e2 | 5944 | const bool unshare = flags & FAULT_FLAG_UNSHARE; |
60d5b473 | 5945 | pte_t pte = huge_ptep_get(ptep); |
a5516438 | 5946 | struct hstate *h = hstate_vma(vma); |
959a78b6 | 5947 | struct folio *old_folio; |
d0ce0e47 | 5948 | struct folio *new_folio; |
2b740303 SJ |
5949 | int outside_reserve = 0; |
5950 | vm_fault_t ret = 0; | |
974e6d66 | 5951 | unsigned long haddr = address & huge_page_mask(h); |
ac46d4f3 | 5952 | struct mmu_notifier_range range; |
1e8f889b | 5953 | |
60d5b473 PX |
5954 | /* |
5955 | * Never handle CoW for uffd-wp protected pages. It should be only | |
5956 | * handled when the uffd-wp protection is removed. | |
5957 | * | |
5958 | * Note that only the CoW optimization path (in hugetlb_no_page()) | |
5959 | * can trigger this, because hugetlb_fault() will always resolve | |
5960 | * uffd-wp bit first. | |
5961 | */ | |
5962 | if (!unshare && huge_pte_uffd_wp(pte)) | |
5963 | return 0; | |
5964 | ||
1d8d1464 DH |
5965 | /* |
5966 | * hugetlb does not support FOLL_FORCE-style write faults that keep the | |
5967 | * PTE mapped R/O such as maybe_mkwrite() would do. | |
5968 | */ | |
5969 | if (WARN_ON_ONCE(!unshare && !(vma->vm_flags & VM_WRITE))) | |
5970 | return VM_FAULT_SIGSEGV; | |
5971 | ||
5972 | /* Let's take out MAP_SHARED mappings first. */ | |
5973 | if (vma->vm_flags & VM_MAYSHARE) { | |
1d8d1464 DH |
5974 | set_huge_ptep_writable(vma, haddr, ptep); |
5975 | return 0; | |
5976 | } | |
5977 | ||
959a78b6 | 5978 | old_folio = page_folio(pte_page(pte)); |
1e8f889b | 5979 | |
662ce1dc YY |
5980 | delayacct_wpcopy_start(); |
5981 | ||
04f2cbe3 | 5982 | retry_avoidcopy: |
c89357e2 DH |
5983 | /* |
5984 | * If no-one else is actually using this page, we're the exclusive | |
5985 | * owner and can reuse this page. | |
5986 | */ | |
959a78b6 | 5987 | if (folio_mapcount(old_folio) == 1 && folio_test_anon(old_folio)) { |
5ca43289 | 5988 | if (!PageAnonExclusive(&old_folio->page)) { |
06968625 | 5989 | folio_move_anon_rmap(old_folio, vma); |
5ca43289 DH |
5990 | SetPageAnonExclusive(&old_folio->page); |
5991 | } | |
c89357e2 DH |
5992 | if (likely(!unshare)) |
5993 | set_huge_ptep_writable(vma, haddr, ptep); | |
662ce1dc YY |
5994 | |
5995 | delayacct_wpcopy_end(); | |
83c54070 | 5996 | return 0; |
1e8f889b | 5997 | } |
959a78b6 Z |
5998 | VM_BUG_ON_PAGE(folio_test_anon(old_folio) && |
5999 | PageAnonExclusive(&old_folio->page), &old_folio->page); | |
1e8f889b | 6000 | |
04f2cbe3 MG |
6001 | /* |
6002 | * If the process that created a MAP_PRIVATE mapping is about to | |
6003 | * perform a COW due to a shared page count, attempt to satisfy | |
6004 | * the allocation without using the existing reserves. The pagecache | |
6005 | * page is used to determine if the reserve at this address was | |
6006 | * consumed or not. If reserves were used, a partial faulted mapping | |
6007 | * at the time of fork() could consume its reserves on COW instead | |
6008 | * of the full address range. | |
6009 | */ | |
5944d011 | 6010 | if (is_vma_resv_set(vma, HPAGE_RESV_OWNER) && |
959a78b6 | 6011 | old_folio != pagecache_folio) |
04f2cbe3 MG |
6012 | outside_reserve = 1; |
6013 | ||
959a78b6 | 6014 | folio_get(old_folio); |
b76c8cfb | 6015 | |
ad4404a2 DB |
6016 | /* |
6017 | * Drop page table lock as buddy allocator may be called. It will | |
6018 | * be acquired again before returning to the caller, as expected. | |
6019 | */ | |
cb900f41 | 6020 | spin_unlock(ptl); |
d0ce0e47 | 6021 | new_folio = alloc_hugetlb_folio(vma, haddr, outside_reserve); |
1e8f889b | 6022 | |
d0ce0e47 | 6023 | if (IS_ERR(new_folio)) { |
04f2cbe3 MG |
6024 | /* |
6025 | * If a process owning a MAP_PRIVATE mapping fails to COW, | |
6026 | * it is due to references held by a child and an insufficient | |
6027 | * huge page pool. To guarantee the original mappers | |
6028 | * reliability, unmap the page from child processes. The child | |
6029 | * may get SIGKILLed if it later faults. | |
6030 | */ | |
6031 | if (outside_reserve) { | |
40549ba8 MK |
6032 | struct address_space *mapping = vma->vm_file->f_mapping; |
6033 | pgoff_t idx; | |
6034 | u32 hash; | |
6035 | ||
959a78b6 | 6036 | folio_put(old_folio); |
40549ba8 MK |
6037 | /* |
6038 | * Drop hugetlb_fault_mutex and vma_lock before | |
6039 | * unmapping. unmapping needs to hold vma_lock | |
6040 | * in write mode. Dropping vma_lock in read mode | |
6041 | * here is OK as COW mappings do not interact with | |
6042 | * PMD sharing. | |
6043 | * | |
6044 | * Reacquire both after unmap operation. | |
6045 | */ | |
6046 | idx = vma_hugecache_offset(h, vma, haddr); | |
6047 | hash = hugetlb_fault_mutex_hash(mapping, idx); | |
6048 | hugetlb_vma_unlock_read(vma); | |
6049 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); | |
6050 | ||
959a78b6 | 6051 | unmap_ref_private(mm, vma, &old_folio->page, haddr); |
40549ba8 MK |
6052 | |
6053 | mutex_lock(&hugetlb_fault_mutex_table[hash]); | |
6054 | hugetlb_vma_lock_read(vma); | |
2f4612af | 6055 | spin_lock(ptl); |
9c67a207 | 6056 | ptep = hugetlb_walk(vma, haddr, huge_page_size(h)); |
2f4612af DB |
6057 | if (likely(ptep && |
6058 | pte_same(huge_ptep_get(ptep), pte))) | |
6059 | goto retry_avoidcopy; | |
6060 | /* | |
6061 | * race occurs while re-acquiring page table | |
6062 | * lock, and our job is done. | |
6063 | */ | |
662ce1dc | 6064 | delayacct_wpcopy_end(); |
2f4612af | 6065 | return 0; |
04f2cbe3 MG |
6066 | } |
6067 | ||
d0ce0e47 | 6068 | ret = vmf_error(PTR_ERR(new_folio)); |
ad4404a2 | 6069 | goto out_release_old; |
1e8f889b DG |
6070 | } |
6071 | ||
0fe6e20b NH |
6072 | /* |
6073 | * When the original hugepage is shared one, it does not have | |
6074 | * anon_vma prepared. | |
6075 | */ | |
9acad7ba VMO |
6076 | ret = vmf_anon_prepare(vmf); |
6077 | if (unlikely(ret)) | |
ad4404a2 | 6078 | goto out_release_all; |
0fe6e20b | 6079 | |
959a78b6 | 6080 | if (copy_user_large_folio(new_folio, old_folio, address, vma)) { |
1cb9dc4b LS |
6081 | ret = VM_FAULT_HWPOISON_LARGE; |
6082 | goto out_release_all; | |
6083 | } | |
d0ce0e47 | 6084 | __folio_mark_uptodate(new_folio); |
1e8f889b | 6085 | |
7d4a8be0 | 6086 | mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm, haddr, |
6f4f13e8 | 6087 | haddr + huge_page_size(h)); |
ac46d4f3 | 6088 | mmu_notifier_invalidate_range_start(&range); |
ad4404a2 | 6089 | |
b76c8cfb | 6090 | /* |
cb900f41 | 6091 | * Retake the page table lock to check for racing updates |
b76c8cfb LW |
6092 | * before the page tables are altered |
6093 | */ | |
cb900f41 | 6094 | spin_lock(ptl); |
9c67a207 | 6095 | ptep = hugetlb_walk(vma, haddr, huge_page_size(h)); |
a9af0c5d | 6096 | if (likely(ptep && pte_same(huge_ptep_get(ptep), pte))) { |
0f230bc2 PX |
6097 | pte_t newpte = make_huge_pte(vma, &new_folio->page, !unshare); |
6098 | ||
c89357e2 | 6099 | /* Break COW or unshare */ |
5b7a1d40 | 6100 | huge_ptep_clear_flush(vma, haddr, ptep); |
e135826b | 6101 | hugetlb_remove_rmap(old_folio); |
9d5fafd5 | 6102 | hugetlb_add_new_anon_rmap(new_folio, vma, haddr); |
0f230bc2 PX |
6103 | if (huge_pte_uffd_wp(pte)) |
6104 | newpte = huge_pte_mkuffd_wp(newpte); | |
935d4f0c | 6105 | set_huge_pte_at(mm, haddr, ptep, newpte, huge_page_size(h)); |
d0ce0e47 | 6106 | folio_set_hugetlb_migratable(new_folio); |
1e8f889b | 6107 | /* Make the old page be freed below */ |
959a78b6 | 6108 | new_folio = old_folio; |
1e8f889b | 6109 | } |
cb900f41 | 6110 | spin_unlock(ptl); |
ac46d4f3 | 6111 | mmu_notifier_invalidate_range_end(&range); |
ad4404a2 | 6112 | out_release_all: |
c89357e2 DH |
6113 | /* |
6114 | * No restore in case of successful pagetable update (Break COW or | |
6115 | * unshare) | |
6116 | */ | |
959a78b6 | 6117 | if (new_folio != old_folio) |
d2d7bb44 | 6118 | restore_reserve_on_error(h, vma, haddr, new_folio); |
d0ce0e47 | 6119 | folio_put(new_folio); |
ad4404a2 | 6120 | out_release_old: |
959a78b6 | 6121 | folio_put(old_folio); |
8312034f | 6122 | |
ad4404a2 | 6123 | spin_lock(ptl); /* Caller expects lock to be held */ |
662ce1dc YY |
6124 | |
6125 | delayacct_wpcopy_end(); | |
ad4404a2 | 6126 | return ret; |
1e8f889b DG |
6127 | } |
6128 | ||
3ae77f43 HD |
6129 | /* |
6130 | * Return whether there is a pagecache page to back given address within VMA. | |
3ae77f43 HD |
6131 | */ |
6132 | static bool hugetlbfs_pagecache_present(struct hstate *h, | |
2a15efc9 HD |
6133 | struct vm_area_struct *vma, unsigned long address) |
6134 | { | |
91a2fb95 | 6135 | struct address_space *mapping = vma->vm_file->f_mapping; |
a08c7193 | 6136 | pgoff_t idx = linear_page_index(vma, address); |
fd4aed8d | 6137 | struct folio *folio; |
2a15efc9 | 6138 | |
fd4aed8d MK |
6139 | folio = filemap_get_folio(mapping, idx); |
6140 | if (IS_ERR(folio)) | |
6141 | return false; | |
6142 | folio_put(folio); | |
6143 | return true; | |
2a15efc9 HD |
6144 | } |
6145 | ||
9b91c0e2 | 6146 | int hugetlb_add_to_page_cache(struct folio *folio, struct address_space *mapping, |
ab76ad54 MK |
6147 | pgoff_t idx) |
6148 | { | |
6149 | struct inode *inode = mapping->host; | |
6150 | struct hstate *h = hstate_inode(inode); | |
d9ef44de | 6151 | int err; |
ab76ad54 | 6152 | |
a08c7193 | 6153 | idx <<= huge_page_order(h); |
d9ef44de MWO |
6154 | __folio_set_locked(folio); |
6155 | err = __filemap_add_folio(mapping, folio, idx, GFP_KERNEL, NULL); | |
6156 | ||
6157 | if (unlikely(err)) { | |
6158 | __folio_clear_locked(folio); | |
ab76ad54 | 6159 | return err; |
d9ef44de | 6160 | } |
9b91c0e2 | 6161 | folio_clear_hugetlb_restore_reserve(folio); |
ab76ad54 | 6162 | |
22146c3c | 6163 | /* |
d9ef44de | 6164 | * mark folio dirty so that it will not be removed from cache/file |
22146c3c MK |
6165 | * by non-hugetlbfs specific code paths. |
6166 | */ | |
d9ef44de | 6167 | folio_mark_dirty(folio); |
22146c3c | 6168 | |
ab76ad54 MK |
6169 | spin_lock(&inode->i_lock); |
6170 | inode->i_blocks += blocks_per_huge_page(h); | |
6171 | spin_unlock(&inode->i_lock); | |
6172 | return 0; | |
6173 | } | |
6174 | ||
7dac0ec8 | 6175 | static inline vm_fault_t hugetlb_handle_userfault(struct vm_fault *vmf, |
7677f7fd | 6176 | struct address_space *mapping, |
7677f7fd AR |
6177 | unsigned long reason) |
6178 | { | |
7677f7fd | 6179 | u32 hash; |
7677f7fd AR |
6180 | |
6181 | /* | |
958f32ce LS |
6182 | * vma_lock and hugetlb_fault_mutex must be dropped before handling |
6183 | * userfault. Also mmap_lock could be dropped due to handling | |
6184 | * userfault, any vma operation should be careful from here. | |
7677f7fd | 6185 | */ |
7dac0ec8 VMO |
6186 | hugetlb_vma_unlock_read(vmf->vma); |
6187 | hash = hugetlb_fault_mutex_hash(mapping, vmf->pgoff); | |
7677f7fd | 6188 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); |
7dac0ec8 | 6189 | return handle_userfault(vmf, reason); |
7677f7fd AR |
6190 | } |
6191 | ||
2ea7ff1e PX |
6192 | /* |
6193 | * Recheck pte with pgtable lock. Returns true if pte didn't change, or | |
6194 | * false if pte changed or is changing. | |
6195 | */ | |
6196 | static bool hugetlb_pte_stable(struct hstate *h, struct mm_struct *mm, | |
6197 | pte_t *ptep, pte_t old_pte) | |
6198 | { | |
6199 | spinlock_t *ptl; | |
6200 | bool same; | |
6201 | ||
6202 | ptl = huge_pte_lock(h, mm, ptep); | |
6203 | same = pte_same(huge_ptep_get(ptep), old_pte); | |
6204 | spin_unlock(ptl); | |
6205 | ||
6206 | return same; | |
6207 | } | |
6208 | ||
2b740303 SJ |
6209 | static vm_fault_t hugetlb_no_page(struct mm_struct *mm, |
6210 | struct vm_area_struct *vma, | |
6211 | struct address_space *mapping, pgoff_t idx, | |
c64e912c | 6212 | unsigned long address, pte_t *ptep, |
7dac0ec8 VMO |
6213 | pte_t old_pte, unsigned int flags, |
6214 | struct vm_fault *vmf) | |
ac9b9c66 | 6215 | { |
a5516438 | 6216 | struct hstate *h = hstate_vma(vma); |
2b740303 | 6217 | vm_fault_t ret = VM_FAULT_SIGBUS; |
409eb8c2 | 6218 | int anon_rmap = 0; |
4c887265 | 6219 | unsigned long size; |
d0ce0e47 | 6220 | struct folio *folio; |
1e8f889b | 6221 | pte_t new_pte; |
cb900f41 | 6222 | spinlock_t *ptl; |
285b8dca | 6223 | unsigned long haddr = address & huge_page_mask(h); |
d0ce0e47 | 6224 | bool new_folio, new_pagecache_folio = false; |
958f32ce | 6225 | u32 hash = hugetlb_fault_mutex_hash(mapping, idx); |
4c887265 | 6226 | |
04f2cbe3 MG |
6227 | /* |
6228 | * Currently, we are forced to kill the process in the event the | |
6229 | * original mapper has unmapped pages from the child due to a failed | |
c89357e2 DH |
6230 | * COW/unsharing. Warn that such a situation has occurred as it may not |
6231 | * be obvious. | |
04f2cbe3 MG |
6232 | */ |
6233 | if (is_vma_resv_set(vma, HPAGE_RESV_UNMAPPED)) { | |
910154d5 | 6234 | pr_warn_ratelimited("PID %d killed due to inadequate hugepage pool\n", |
ffb22af5 | 6235 | current->pid); |
958f32ce | 6236 | goto out; |
04f2cbe3 MG |
6237 | } |
6238 | ||
4c887265 | 6239 | /* |
188a3972 MK |
6240 | * Use page lock to guard against racing truncation |
6241 | * before we get page_table_lock. | |
4c887265 | 6242 | */ |
d0ce0e47 | 6243 | new_folio = false; |
a08c7193 | 6244 | folio = filemap_lock_hugetlb_folio(h, mapping, idx); |
66dabbb6 | 6245 | if (IS_ERR(folio)) { |
188a3972 MK |
6246 | size = i_size_read(mapping->host) >> huge_page_shift(h); |
6247 | if (idx >= size) | |
6248 | goto out; | |
7677f7fd | 6249 | /* Check for page in userfault range */ |
2ea7ff1e PX |
6250 | if (userfaultfd_missing(vma)) { |
6251 | /* | |
6252 | * Since hugetlb_no_page() was examining pte | |
6253 | * without pgtable lock, we need to re-test under | |
6254 | * lock because the pte may not be stable and could | |
6255 | * have changed from under us. Try to detect | |
6256 | * either changed or during-changing ptes and retry | |
6257 | * properly when needed. | |
6258 | * | |
6259 | * Note that userfaultfd is actually fine with | |
6260 | * false positives (e.g. caused by pte changed), | |
6261 | * but not wrong logical events (e.g. caused by | |
6262 | * reading a pte during changing). The latter can | |
6263 | * confuse the userspace, so the strictness is very | |
6264 | * much preferred. E.g., MISSING event should | |
6265 | * never happen on the page after UFFDIO_COPY has | |
6266 | * correctly installed the page and returned. | |
6267 | */ | |
6268 | if (!hugetlb_pte_stable(h, mm, ptep, old_pte)) { | |
6269 | ret = 0; | |
6270 | goto out; | |
6271 | } | |
6272 | ||
7dac0ec8 | 6273 | return hugetlb_handle_userfault(vmf, mapping, |
2ea7ff1e PX |
6274 | VM_UFFD_MISSING); |
6275 | } | |
1a1aad8a | 6276 | |
d0ce0e47 SK |
6277 | folio = alloc_hugetlb_folio(vma, haddr, 0); |
6278 | if (IS_ERR(folio)) { | |
4643d67e MK |
6279 | /* |
6280 | * Returning error will result in faulting task being | |
6281 | * sent SIGBUS. The hugetlb fault mutex prevents two | |
6282 | * tasks from racing to fault in the same page which | |
6283 | * could result in false unable to allocate errors. | |
6284 | * Page migration does not take the fault mutex, but | |
6285 | * does a clear then write of pte's under page table | |
6286 | * lock. Page fault code could race with migration, | |
6287 | * notice the clear pte and try to allocate a page | |
6288 | * here. Before returning error, get ptl and make | |
6289 | * sure there really is no pte entry. | |
6290 | */ | |
f9bf6c03 | 6291 | if (hugetlb_pte_stable(h, mm, ptep, old_pte)) |
d0ce0e47 | 6292 | ret = vmf_error(PTR_ERR(folio)); |
f9bf6c03 PX |
6293 | else |
6294 | ret = 0; | |
6bda666a CL |
6295 | goto out; |
6296 | } | |
d0ce0e47 SK |
6297 | clear_huge_page(&folio->page, address, pages_per_huge_page(h)); |
6298 | __folio_mark_uptodate(folio); | |
6299 | new_folio = true; | |
ac9b9c66 | 6300 | |
f83a275d | 6301 | if (vma->vm_flags & VM_MAYSHARE) { |
9b91c0e2 | 6302 | int err = hugetlb_add_to_page_cache(folio, mapping, idx); |
6bda666a | 6303 | if (err) { |
3a5497a2 ML |
6304 | /* |
6305 | * err can't be -EEXIST which implies someone | |
6306 | * else consumed the reservation since hugetlb | |
6307 | * fault mutex is held when add a hugetlb page | |
6308 | * to the page cache. So it's safe to call | |
6309 | * restore_reserve_on_error() here. | |
6310 | */ | |
d2d7bb44 | 6311 | restore_reserve_on_error(h, vma, haddr, folio); |
d0ce0e47 | 6312 | folio_put(folio); |
6bda666a CL |
6313 | goto out; |
6314 | } | |
d0ce0e47 | 6315 | new_pagecache_folio = true; |
23be7468 | 6316 | } else { |
d0ce0e47 | 6317 | folio_lock(folio); |
9acad7ba VMO |
6318 | |
6319 | ret = vmf_anon_prepare(vmf); | |
6320 | if (unlikely(ret)) | |
0fe6e20b | 6321 | goto backout_unlocked; |
409eb8c2 | 6322 | anon_rmap = 1; |
23be7468 | 6323 | } |
0fe6e20b | 6324 | } else { |
998b4382 NH |
6325 | /* |
6326 | * If memory error occurs between mmap() and fault, some process | |
6327 | * don't have hwpoisoned swap entry for errored virtual address. | |
6328 | * So we need to block hugepage fault by PG_hwpoison bit check. | |
6329 | */ | |
d0ce0e47 | 6330 | if (unlikely(folio_test_hwpoison(folio))) { |
0eb98f15 | 6331 | ret = VM_FAULT_HWPOISON_LARGE | |
972dc4de | 6332 | VM_FAULT_SET_HINDEX(hstate_index(h)); |
998b4382 NH |
6333 | goto backout_unlocked; |
6334 | } | |
7677f7fd AR |
6335 | |
6336 | /* Check for page in userfault range. */ | |
6337 | if (userfaultfd_minor(vma)) { | |
d0ce0e47 SK |
6338 | folio_unlock(folio); |
6339 | folio_put(folio); | |
2ea7ff1e PX |
6340 | /* See comment in userfaultfd_missing() block above */ |
6341 | if (!hugetlb_pte_stable(h, mm, ptep, old_pte)) { | |
6342 | ret = 0; | |
6343 | goto out; | |
6344 | } | |
7dac0ec8 | 6345 | return hugetlb_handle_userfault(vmf, mapping, |
2ea7ff1e | 6346 | VM_UFFD_MINOR); |
7677f7fd | 6347 | } |
6bda666a | 6348 | } |
1e8f889b | 6349 | |
57303d80 AW |
6350 | /* |
6351 | * If we are going to COW a private mapping later, we examine the | |
6352 | * pending reservations for this page now. This will ensure that | |
6353 | * any allocations necessary to record that reservation occur outside | |
6354 | * the spinlock. | |
6355 | */ | |
5e911373 | 6356 | if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) { |
285b8dca | 6357 | if (vma_needs_reservation(h, vma, haddr) < 0) { |
2b26736c AW |
6358 | ret = VM_FAULT_OOM; |
6359 | goto backout_unlocked; | |
6360 | } | |
5e911373 | 6361 | /* Just decrements count, does not deallocate */ |
285b8dca | 6362 | vma_end_reservation(h, vma, haddr); |
5e911373 | 6363 | } |
57303d80 | 6364 | |
8bea8052 | 6365 | ptl = huge_pte_lock(h, mm, ptep); |
83c54070 | 6366 | ret = 0; |
c64e912c PX |
6367 | /* If pte changed from under us, retry */ |
6368 | if (!pte_same(huge_ptep_get(ptep), old_pte)) | |
4c887265 AL |
6369 | goto backout; |
6370 | ||
4781593d | 6371 | if (anon_rmap) |
9d5fafd5 | 6372 | hugetlb_add_new_anon_rmap(folio, vma, haddr); |
4781593d | 6373 | else |
44887f39 | 6374 | hugetlb_add_file_rmap(folio); |
d0ce0e47 | 6375 | new_pte = make_huge_pte(vma, &folio->page, ((vma->vm_flags & VM_WRITE) |
1e8f889b | 6376 | && (vma->vm_flags & VM_SHARED))); |
c64e912c PX |
6377 | /* |
6378 | * If this pte was previously wr-protected, keep it wr-protected even | |
6379 | * if populated. | |
6380 | */ | |
6381 | if (unlikely(pte_marker_uffd_wp(old_pte))) | |
f1eb1bac | 6382 | new_pte = huge_pte_mkuffd_wp(new_pte); |
935d4f0c | 6383 | set_huge_pte_at(mm, haddr, ptep, new_pte, huge_page_size(h)); |
1e8f889b | 6384 | |
5d317b2b | 6385 | hugetlb_count_add(pages_per_huge_page(h), mm); |
788c7df4 | 6386 | if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) { |
1e8f889b | 6387 | /* Optimization, do the COW without a second fault */ |
9acad7ba | 6388 | ret = hugetlb_wp(mm, vma, address, ptep, flags, folio, ptl, vmf); |
1e8f889b DG |
6389 | } |
6390 | ||
cb900f41 | 6391 | spin_unlock(ptl); |
cb6acd01 MK |
6392 | |
6393 | /* | |
d0ce0e47 SK |
6394 | * Only set hugetlb_migratable in newly allocated pages. Existing pages |
6395 | * found in the pagecache may not have hugetlb_migratable if they have | |
8f251a3d | 6396 | * been isolated for migration. |
cb6acd01 | 6397 | */ |
d0ce0e47 SK |
6398 | if (new_folio) |
6399 | folio_set_hugetlb_migratable(folio); | |
cb6acd01 | 6400 | |
d0ce0e47 | 6401 | folio_unlock(folio); |
4c887265 | 6402 | out: |
958f32ce LS |
6403 | hugetlb_vma_unlock_read(vma); |
6404 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); | |
ac9b9c66 | 6405 | return ret; |
4c887265 AL |
6406 | |
6407 | backout: | |
cb900f41 | 6408 | spin_unlock(ptl); |
2b26736c | 6409 | backout_unlocked: |
d0ce0e47 | 6410 | if (new_folio && !new_pagecache_folio) |
d2d7bb44 | 6411 | restore_reserve_on_error(h, vma, haddr, folio); |
fa27759a | 6412 | |
d0ce0e47 SK |
6413 | folio_unlock(folio); |
6414 | folio_put(folio); | |
4c887265 | 6415 | goto out; |
ac9b9c66 HD |
6416 | } |
6417 | ||
8382d914 | 6418 | #ifdef CONFIG_SMP |
188b04a7 | 6419 | u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx) |
8382d914 DB |
6420 | { |
6421 | unsigned long key[2]; | |
6422 | u32 hash; | |
6423 | ||
1b426bac MK |
6424 | key[0] = (unsigned long) mapping; |
6425 | key[1] = idx; | |
8382d914 | 6426 | |
55254636 | 6427 | hash = jhash2((u32 *)&key, sizeof(key)/(sizeof(u32)), 0); |
8382d914 DB |
6428 | |
6429 | return hash & (num_fault_mutexes - 1); | |
6430 | } | |
6431 | #else | |
6432 | /* | |
6c26d310 | 6433 | * For uniprocessor systems we always use a single mutex, so just |
8382d914 DB |
6434 | * return 0 and avoid the hashing overhead. |
6435 | */ | |
188b04a7 | 6436 | u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx) |
8382d914 DB |
6437 | { |
6438 | return 0; | |
6439 | } | |
6440 | #endif | |
6441 | ||
2b740303 | 6442 | vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, |
788c7df4 | 6443 | unsigned long address, unsigned int flags) |
86e5216f | 6444 | { |
8382d914 | 6445 | pte_t *ptep, entry; |
cb900f41 | 6446 | spinlock_t *ptl; |
2b740303 | 6447 | vm_fault_t ret; |
8382d914 | 6448 | u32 hash; |
061e62e8 | 6449 | struct folio *folio = NULL; |
371607a3 | 6450 | struct folio *pagecache_folio = NULL; |
a5516438 | 6451 | struct hstate *h = hstate_vma(vma); |
8382d914 | 6452 | struct address_space *mapping; |
0f792cf9 | 6453 | int need_wait_lock = 0; |
285b8dca | 6454 | unsigned long haddr = address & huge_page_mask(h); |
0ca22723 VMO |
6455 | struct vm_fault vmf = { |
6456 | .vma = vma, | |
6457 | .address = haddr, | |
6458 | .real_address = address, | |
6459 | .flags = flags, | |
6460 | .pgoff = vma_hugecache_offset(h, vma, haddr), | |
6461 | /* TODO: Track hugetlb faults using vm_fault */ | |
6462 | ||
6463 | /* | |
6464 | * Some fields may not be initialized, be careful as it may | |
6465 | * be hard to debug if called functions make assumptions | |
6466 | */ | |
6467 | }; | |
86e5216f | 6468 | |
3935baa9 DG |
6469 | /* |
6470 | * Serialize hugepage allocation and instantiation, so that we don't | |
6471 | * get spurious allocation failures if two CPUs race to instantiate | |
6472 | * the same page in the page cache. | |
6473 | */ | |
40549ba8 | 6474 | mapping = vma->vm_file->f_mapping; |
0ca22723 | 6475 | hash = hugetlb_fault_mutex_hash(mapping, vmf.pgoff); |
c672c7f2 | 6476 | mutex_lock(&hugetlb_fault_mutex_table[hash]); |
8382d914 | 6477 | |
40549ba8 MK |
6478 | /* |
6479 | * Acquire vma lock before calling huge_pte_alloc and hold | |
6480 | * until finished with ptep. This prevents huge_pmd_unshare from | |
6481 | * being called elsewhere and making the ptep no longer valid. | |
40549ba8 MK |
6482 | */ |
6483 | hugetlb_vma_lock_read(vma); | |
6484 | ptep = huge_pte_alloc(mm, vma, haddr, huge_page_size(h)); | |
6485 | if (!ptep) { | |
6486 | hugetlb_vma_unlock_read(vma); | |
6487 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); | |
6488 | return VM_FAULT_OOM; | |
6489 | } | |
6490 | ||
7f2e9525 | 6491 | entry = huge_ptep_get(ptep); |
af19487f AR |
6492 | if (huge_pte_none_mostly(entry)) { |
6493 | if (is_pte_marker(entry)) { | |
6494 | pte_marker marker = | |
6495 | pte_marker_get(pte_to_swp_entry(entry)); | |
6496 | ||
6497 | if (marker & PTE_MARKER_POISONED) { | |
6498 | ret = VM_FAULT_HWPOISON_LARGE; | |
6499 | goto out_mutex; | |
6500 | } | |
6501 | } | |
6502 | ||
958f32ce | 6503 | /* |
af19487f AR |
6504 | * Other PTE markers should be handled the same way as none PTE. |
6505 | * | |
958f32ce LS |
6506 | * hugetlb_no_page will drop vma lock and hugetlb fault |
6507 | * mutex internally, which make us return immediately. | |
6508 | */ | |
0ca22723 | 6509 | return hugetlb_no_page(mm, vma, mapping, vmf.pgoff, address, |
7dac0ec8 | 6510 | ptep, entry, flags, &vmf); |
af19487f | 6511 | } |
86e5216f | 6512 | |
83c54070 | 6513 | ret = 0; |
1e8f889b | 6514 | |
0f792cf9 NH |
6515 | /* |
6516 | * entry could be a migration/hwpoison entry at this point, so this | |
6517 | * check prevents the kernel from going below assuming that we have | |
7c8de358 EP |
6518 | * an active hugepage in pagecache. This goto expects the 2nd page |
6519 | * fault, and is_hugetlb_entry_(migration|hwpoisoned) check will | |
6520 | * properly handle it. | |
0f792cf9 | 6521 | */ |
fcd48540 PX |
6522 | if (!pte_present(entry)) { |
6523 | if (unlikely(is_hugetlb_entry_migration(entry))) { | |
6524 | /* | |
6525 | * Release the hugetlb fault lock now, but retain | |
6526 | * the vma lock, because it is needed to guard the | |
6527 | * huge_pte_lockptr() later in | |
6528 | * migration_entry_wait_huge(). The vma lock will | |
6529 | * be released there. | |
6530 | */ | |
6531 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); | |
6532 | migration_entry_wait_huge(vma, ptep); | |
6533 | return 0; | |
6534 | } else if (unlikely(is_hugetlb_entry_hwpoisoned(entry))) | |
6535 | ret = VM_FAULT_HWPOISON_LARGE | | |
6536 | VM_FAULT_SET_HINDEX(hstate_index(h)); | |
0f792cf9 | 6537 | goto out_mutex; |
fcd48540 | 6538 | } |
0f792cf9 | 6539 | |
57303d80 | 6540 | /* |
c89357e2 DH |
6541 | * If we are going to COW/unshare the mapping later, we examine the |
6542 | * pending reservations for this page now. This will ensure that any | |
57303d80 | 6543 | * allocations necessary to record that reservation occur outside the |
1d8d1464 DH |
6544 | * spinlock. Also lookup the pagecache page now as it is used to |
6545 | * determine if a reservation has been consumed. | |
57303d80 | 6546 | */ |
c89357e2 | 6547 | if ((flags & (FAULT_FLAG_WRITE|FAULT_FLAG_UNSHARE)) && |
1d8d1464 | 6548 | !(vma->vm_flags & VM_MAYSHARE) && !huge_pte_write(entry)) { |
285b8dca | 6549 | if (vma_needs_reservation(h, vma, haddr) < 0) { |
2b26736c | 6550 | ret = VM_FAULT_OOM; |
b4d1d99f | 6551 | goto out_mutex; |
2b26736c | 6552 | } |
5e911373 | 6553 | /* Just decrements count, does not deallocate */ |
285b8dca | 6554 | vma_end_reservation(h, vma, haddr); |
57303d80 | 6555 | |
0ca22723 VMO |
6556 | pagecache_folio = filemap_lock_hugetlb_folio(h, mapping, |
6557 | vmf.pgoff); | |
66dabbb6 CH |
6558 | if (IS_ERR(pagecache_folio)) |
6559 | pagecache_folio = NULL; | |
57303d80 AW |
6560 | } |
6561 | ||
0f792cf9 NH |
6562 | ptl = huge_pte_lock(h, mm, ptep); |
6563 | ||
c89357e2 | 6564 | /* Check for a racing update before calling hugetlb_wp() */ |
0f792cf9 NH |
6565 | if (unlikely(!pte_same(entry, huge_ptep_get(ptep)))) |
6566 | goto out_ptl; | |
6567 | ||
166f3ecc PX |
6568 | /* Handle userfault-wp first, before trying to lock more pages */ |
6569 | if (userfaultfd_wp(vma) && huge_pte_uffd_wp(huge_ptep_get(ptep)) && | |
6570 | (flags & FAULT_FLAG_WRITE) && !huge_pte_write(entry)) { | |
d61ea1cb | 6571 | if (!userfaultfd_wp_async(vma)) { |
d61ea1cb PX |
6572 | spin_unlock(ptl); |
6573 | if (pagecache_folio) { | |
6574 | folio_unlock(pagecache_folio); | |
6575 | folio_put(pagecache_folio); | |
6576 | } | |
6577 | hugetlb_vma_unlock_read(vma); | |
6578 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); | |
6579 | return handle_userfault(&vmf, VM_UFFD_WP); | |
166f3ecc | 6580 | } |
d61ea1cb PX |
6581 | |
6582 | entry = huge_pte_clear_uffd_wp(entry); | |
52526ca7 MUA |
6583 | set_huge_pte_at(mm, haddr, ptep, entry, |
6584 | huge_page_size(hstate_vma(vma))); | |
d61ea1cb | 6585 | /* Fallthrough to CoW */ |
166f3ecc PX |
6586 | } |
6587 | ||
56c9cfb1 | 6588 | /* |
c89357e2 | 6589 | * hugetlb_wp() requires page locks of pte_page(entry) and |
371607a3 | 6590 | * pagecache_folio, so here we need take the former one |
061e62e8 | 6591 | * when folio != pagecache_folio or !pagecache_folio. |
56c9cfb1 | 6592 | */ |
061e62e8 Z |
6593 | folio = page_folio(pte_page(entry)); |
6594 | if (folio != pagecache_folio) | |
6595 | if (!folio_trylock(folio)) { | |
0f792cf9 NH |
6596 | need_wait_lock = 1; |
6597 | goto out_ptl; | |
6598 | } | |
b4d1d99f | 6599 | |
061e62e8 | 6600 | folio_get(folio); |
b4d1d99f | 6601 | |
c89357e2 | 6602 | if (flags & (FAULT_FLAG_WRITE|FAULT_FLAG_UNSHARE)) { |
106c992a | 6603 | if (!huge_pte_write(entry)) { |
c89357e2 | 6604 | ret = hugetlb_wp(mm, vma, address, ptep, flags, |
9acad7ba | 6605 | pagecache_folio, ptl, &vmf); |
0f792cf9 | 6606 | goto out_put_page; |
c89357e2 DH |
6607 | } else if (likely(flags & FAULT_FLAG_WRITE)) { |
6608 | entry = huge_pte_mkdirty(entry); | |
b4d1d99f | 6609 | } |
b4d1d99f DG |
6610 | } |
6611 | entry = pte_mkyoung(entry); | |
285b8dca | 6612 | if (huge_ptep_set_access_flags(vma, haddr, ptep, entry, |
788c7df4 | 6613 | flags & FAULT_FLAG_WRITE)) |
285b8dca | 6614 | update_mmu_cache(vma, haddr, ptep); |
0f792cf9 | 6615 | out_put_page: |
061e62e8 Z |
6616 | if (folio != pagecache_folio) |
6617 | folio_unlock(folio); | |
6618 | folio_put(folio); | |
cb900f41 KS |
6619 | out_ptl: |
6620 | spin_unlock(ptl); | |
57303d80 | 6621 | |
371607a3 SK |
6622 | if (pagecache_folio) { |
6623 | folio_unlock(pagecache_folio); | |
6624 | folio_put(pagecache_folio); | |
57303d80 | 6625 | } |
b4d1d99f | 6626 | out_mutex: |
40549ba8 | 6627 | hugetlb_vma_unlock_read(vma); |
c672c7f2 | 6628 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); |
0f792cf9 NH |
6629 | /* |
6630 | * Generally it's safe to hold refcount during waiting page lock. But | |
6631 | * here we just wait to defer the next page fault to avoid busy loop and | |
6632 | * the page is not used after unlocked before returning from the current | |
6633 | * page fault. So we are safe from accessing freed page, even if we wait | |
6634 | * here without taking refcount. | |
6635 | */ | |
6636 | if (need_wait_lock) | |
061e62e8 | 6637 | folio_wait_locked(folio); |
1e8f889b | 6638 | return ret; |
86e5216f AL |
6639 | } |
6640 | ||
714c1891 | 6641 | #ifdef CONFIG_USERFAULTFD |
72e315f7 HD |
6642 | /* |
6643 | * Can probably be eliminated, but still used by hugetlb_mfill_atomic_pte(). | |
6644 | */ | |
6645 | static struct folio *alloc_hugetlb_folio_vma(struct hstate *h, | |
6646 | struct vm_area_struct *vma, unsigned long address) | |
6647 | { | |
6648 | struct mempolicy *mpol; | |
6649 | nodemask_t *nodemask; | |
6650 | struct folio *folio; | |
6651 | gfp_t gfp_mask; | |
6652 | int node; | |
6653 | ||
6654 | gfp_mask = htlb_alloc_mask(h); | |
6655 | node = huge_node(vma, address, gfp_mask, &mpol, &nodemask); | |
6656 | folio = alloc_hugetlb_folio_nodemask(h, node, nodemask, gfp_mask); | |
6657 | mpol_cond_put(mpol); | |
6658 | ||
6659 | return folio; | |
6660 | } | |
6661 | ||
8fb5debc | 6662 | /* |
a734991c AR |
6663 | * Used by userfaultfd UFFDIO_* ioctls. Based on userfaultfd's mfill_atomic_pte |
6664 | * with modifications for hugetlb pages. | |
8fb5debc | 6665 | */ |
61c50040 | 6666 | int hugetlb_mfill_atomic_pte(pte_t *dst_pte, |
a734991c AR |
6667 | struct vm_area_struct *dst_vma, |
6668 | unsigned long dst_addr, | |
6669 | unsigned long src_addr, | |
d9712937 | 6670 | uffd_flags_t flags, |
0169fd51 | 6671 | struct folio **foliop) |
8fb5debc | 6672 | { |
61c50040 | 6673 | struct mm_struct *dst_mm = dst_vma->vm_mm; |
d9712937 AR |
6674 | bool is_continue = uffd_flags_mode_is(flags, MFILL_ATOMIC_CONTINUE); |
6675 | bool wp_enabled = (flags & MFILL_ATOMIC_WP); | |
8cc5fcbb MA |
6676 | struct hstate *h = hstate_vma(dst_vma); |
6677 | struct address_space *mapping = dst_vma->vm_file->f_mapping; | |
6678 | pgoff_t idx = vma_hugecache_offset(h, dst_vma, dst_addr); | |
1e392147 | 6679 | unsigned long size; |
1c9e8def | 6680 | int vm_shared = dst_vma->vm_flags & VM_SHARED; |
8fb5debc MK |
6681 | pte_t _dst_pte; |
6682 | spinlock_t *ptl; | |
8cc5fcbb | 6683 | int ret = -ENOMEM; |
d0ce0e47 | 6684 | struct folio *folio; |
f6191471 | 6685 | int writable; |
d0ce0e47 | 6686 | bool folio_in_pagecache = false; |
8fb5debc | 6687 | |
8a13897f AR |
6688 | if (uffd_flags_mode_is(flags, MFILL_ATOMIC_POISON)) { |
6689 | ptl = huge_pte_lock(h, dst_mm, dst_pte); | |
6690 | ||
6691 | /* Don't overwrite any existing PTEs (even markers) */ | |
6692 | if (!huge_pte_none(huge_ptep_get(dst_pte))) { | |
6693 | spin_unlock(ptl); | |
6694 | return -EEXIST; | |
6695 | } | |
6696 | ||
6697 | _dst_pte = make_pte_marker(PTE_MARKER_POISONED); | |
935d4f0c RR |
6698 | set_huge_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte, |
6699 | huge_page_size(h)); | |
8a13897f AR |
6700 | |
6701 | /* No need to invalidate - it was non-present before */ | |
6702 | update_mmu_cache(dst_vma, dst_addr, dst_pte); | |
6703 | ||
6704 | spin_unlock(ptl); | |
6705 | return 0; | |
6706 | } | |
6707 | ||
f6191471 AR |
6708 | if (is_continue) { |
6709 | ret = -EFAULT; | |
a08c7193 | 6710 | folio = filemap_lock_hugetlb_folio(h, mapping, idx); |
66dabbb6 | 6711 | if (IS_ERR(folio)) |
f6191471 | 6712 | goto out; |
d0ce0e47 | 6713 | folio_in_pagecache = true; |
0169fd51 Z |
6714 | } else if (!*foliop) { |
6715 | /* If a folio already exists, then it's UFFDIO_COPY for | |
d84cf06e MA |
6716 | * a non-missing case. Return -EEXIST. |
6717 | */ | |
6718 | if (vm_shared && | |
6719 | hugetlbfs_pagecache_present(h, dst_vma, dst_addr)) { | |
6720 | ret = -EEXIST; | |
6721 | goto out; | |
6722 | } | |
6723 | ||
d0ce0e47 SK |
6724 | folio = alloc_hugetlb_folio(dst_vma, dst_addr, 0); |
6725 | if (IS_ERR(folio)) { | |
d84cf06e | 6726 | ret = -ENOMEM; |
8fb5debc | 6727 | goto out; |
d84cf06e | 6728 | } |
8fb5debc | 6729 | |
e87340ca Z |
6730 | ret = copy_folio_from_user(folio, (const void __user *) src_addr, |
6731 | false); | |
8fb5debc | 6732 | |
c1e8d7c6 | 6733 | /* fallback to copy_from_user outside mmap_lock */ |
8fb5debc | 6734 | if (unlikely(ret)) { |
9e368259 | 6735 | ret = -ENOENT; |
d0ce0e47 | 6736 | /* Free the allocated folio which may have |
8cc5fcbb MA |
6737 | * consumed a reservation. |
6738 | */ | |
d2d7bb44 | 6739 | restore_reserve_on_error(h, dst_vma, dst_addr, folio); |
d0ce0e47 | 6740 | folio_put(folio); |
8cc5fcbb | 6741 | |
d0ce0e47 | 6742 | /* Allocate a temporary folio to hold the copied |
8cc5fcbb MA |
6743 | * contents. |
6744 | */ | |
d0ce0e47 SK |
6745 | folio = alloc_hugetlb_folio_vma(h, dst_vma, dst_addr); |
6746 | if (!folio) { | |
8cc5fcbb MA |
6747 | ret = -ENOMEM; |
6748 | goto out; | |
6749 | } | |
0169fd51 Z |
6750 | *foliop = folio; |
6751 | /* Set the outparam foliop and return to the caller to | |
8cc5fcbb | 6752 | * copy the contents outside the lock. Don't free the |
0169fd51 | 6753 | * folio. |
8cc5fcbb | 6754 | */ |
8fb5debc MK |
6755 | goto out; |
6756 | } | |
6757 | } else { | |
8cc5fcbb MA |
6758 | if (vm_shared && |
6759 | hugetlbfs_pagecache_present(h, dst_vma, dst_addr)) { | |
0169fd51 | 6760 | folio_put(*foliop); |
8cc5fcbb | 6761 | ret = -EEXIST; |
0169fd51 | 6762 | *foliop = NULL; |
8cc5fcbb MA |
6763 | goto out; |
6764 | } | |
6765 | ||
d0ce0e47 SK |
6766 | folio = alloc_hugetlb_folio(dst_vma, dst_addr, 0); |
6767 | if (IS_ERR(folio)) { | |
0169fd51 | 6768 | folio_put(*foliop); |
8cc5fcbb | 6769 | ret = -ENOMEM; |
0169fd51 | 6770 | *foliop = NULL; |
8cc5fcbb MA |
6771 | goto out; |
6772 | } | |
1cb9dc4b | 6773 | ret = copy_user_large_folio(folio, *foliop, dst_addr, dst_vma); |
0169fd51 Z |
6774 | folio_put(*foliop); |
6775 | *foliop = NULL; | |
1cb9dc4b LS |
6776 | if (ret) { |
6777 | folio_put(folio); | |
8cc5fcbb MA |
6778 | goto out; |
6779 | } | |
8fb5debc MK |
6780 | } |
6781 | ||
6782 | /* | |
b14d1671 JH |
6783 | * If we just allocated a new page, we need a memory barrier to ensure |
6784 | * that preceding stores to the page become visible before the | |
6785 | * set_pte_at() write. The memory barrier inside __folio_mark_uptodate | |
6786 | * is what we need. | |
6787 | * | |
6788 | * In the case where we have not allocated a new page (is_continue), | |
6789 | * the page must already be uptodate. UFFDIO_CONTINUE already includes | |
6790 | * an earlier smp_wmb() to ensure that prior stores will be visible | |
6791 | * before the set_pte_at() write. | |
8fb5debc | 6792 | */ |
b14d1671 JH |
6793 | if (!is_continue) |
6794 | __folio_mark_uptodate(folio); | |
6795 | else | |
6796 | WARN_ON_ONCE(!folio_test_uptodate(folio)); | |
8fb5debc | 6797 | |
f6191471 AR |
6798 | /* Add shared, newly allocated pages to the page cache. */ |
6799 | if (vm_shared && !is_continue) { | |
1e392147 AA |
6800 | size = i_size_read(mapping->host) >> huge_page_shift(h); |
6801 | ret = -EFAULT; | |
6802 | if (idx >= size) | |
6803 | goto out_release_nounlock; | |
1c9e8def | 6804 | |
1e392147 AA |
6805 | /* |
6806 | * Serialization between remove_inode_hugepages() and | |
7e1813d4 | 6807 | * hugetlb_add_to_page_cache() below happens through the |
1e392147 AA |
6808 | * hugetlb_fault_mutex_table that here must be hold by |
6809 | * the caller. | |
6810 | */ | |
9b91c0e2 | 6811 | ret = hugetlb_add_to_page_cache(folio, mapping, idx); |
1c9e8def MK |
6812 | if (ret) |
6813 | goto out_release_nounlock; | |
d0ce0e47 | 6814 | folio_in_pagecache = true; |
1c9e8def MK |
6815 | } |
6816 | ||
bcc66543 | 6817 | ptl = huge_pte_lock(h, dst_mm, dst_pte); |
8fb5debc | 6818 | |
8625147c | 6819 | ret = -EIO; |
d0ce0e47 | 6820 | if (folio_test_hwpoison(folio)) |
8625147c JH |
6821 | goto out_release_unlock; |
6822 | ||
6041c691 PX |
6823 | /* |
6824 | * We allow to overwrite a pte marker: consider when both MISSING|WP | |
6825 | * registered, we firstly wr-protect a none pte which has no page cache | |
6826 | * page backing it, then access the page. | |
6827 | */ | |
fa27759a | 6828 | ret = -EEXIST; |
6041c691 | 6829 | if (!huge_pte_none_mostly(huge_ptep_get(dst_pte))) |
8fb5debc MK |
6830 | goto out_release_unlock; |
6831 | ||
d0ce0e47 | 6832 | if (folio_in_pagecache) |
44887f39 | 6833 | hugetlb_add_file_rmap(folio); |
4781593d | 6834 | else |
9d5fafd5 | 6835 | hugetlb_add_new_anon_rmap(folio, dst_vma, dst_addr); |
8fb5debc | 6836 | |
6041c691 PX |
6837 | /* |
6838 | * For either: (1) CONTINUE on a non-shared VMA, or (2) UFFDIO_COPY | |
6839 | * with wp flag set, don't set pte write bit. | |
6840 | */ | |
d9712937 | 6841 | if (wp_enabled || (is_continue && !vm_shared)) |
f6191471 AR |
6842 | writable = 0; |
6843 | else | |
6844 | writable = dst_vma->vm_flags & VM_WRITE; | |
6845 | ||
d0ce0e47 | 6846 | _dst_pte = make_huge_pte(dst_vma, &folio->page, writable); |
6041c691 PX |
6847 | /* |
6848 | * Always mark UFFDIO_COPY page dirty; note that this may not be | |
6849 | * extremely important for hugetlbfs for now since swapping is not | |
6850 | * supported, but we should still be clear in that this page cannot be | |
6851 | * thrown away at will, even if write bit not set. | |
6852 | */ | |
6853 | _dst_pte = huge_pte_mkdirty(_dst_pte); | |
8fb5debc MK |
6854 | _dst_pte = pte_mkyoung(_dst_pte); |
6855 | ||
d9712937 | 6856 | if (wp_enabled) |
6041c691 PX |
6857 | _dst_pte = huge_pte_mkuffd_wp(_dst_pte); |
6858 | ||
935d4f0c | 6859 | set_huge_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte, huge_page_size(h)); |
8fb5debc | 6860 | |
8fb5debc MK |
6861 | hugetlb_count_add(pages_per_huge_page(h), dst_mm); |
6862 | ||
6863 | /* No need to invalidate - it was non-present before */ | |
6864 | update_mmu_cache(dst_vma, dst_addr, dst_pte); | |
6865 | ||
6866 | spin_unlock(ptl); | |
f6191471 | 6867 | if (!is_continue) |
d0ce0e47 | 6868 | folio_set_hugetlb_migratable(folio); |
f6191471 | 6869 | if (vm_shared || is_continue) |
d0ce0e47 | 6870 | folio_unlock(folio); |
8fb5debc MK |
6871 | ret = 0; |
6872 | out: | |
6873 | return ret; | |
6874 | out_release_unlock: | |
6875 | spin_unlock(ptl); | |
f6191471 | 6876 | if (vm_shared || is_continue) |
d0ce0e47 | 6877 | folio_unlock(folio); |
5af10dfd | 6878 | out_release_nounlock: |
d0ce0e47 | 6879 | if (!folio_in_pagecache) |
d2d7bb44 | 6880 | restore_reserve_on_error(h, dst_vma, dst_addr, folio); |
d0ce0e47 | 6881 | folio_put(folio); |
8fb5debc MK |
6882 | goto out; |
6883 | } | |
714c1891 | 6884 | #endif /* CONFIG_USERFAULTFD */ |
8fb5debc | 6885 | |
57a196a5 | 6886 | struct page *hugetlb_follow_page_mask(struct vm_area_struct *vma, |
5502ea44 PX |
6887 | unsigned long address, unsigned int flags, |
6888 | unsigned int *page_mask) | |
57a196a5 MK |
6889 | { |
6890 | struct hstate *h = hstate_vma(vma); | |
6891 | struct mm_struct *mm = vma->vm_mm; | |
6892 | unsigned long haddr = address & huge_page_mask(h); | |
6893 | struct page *page = NULL; | |
6894 | spinlock_t *ptl; | |
6895 | pte_t *pte, entry; | |
458568c9 | 6896 | int ret; |
57a196a5 | 6897 | |
7d049f3a | 6898 | hugetlb_vma_lock_read(vma); |
9c67a207 | 6899 | pte = hugetlb_walk(vma, haddr, huge_page_size(h)); |
57a196a5 | 6900 | if (!pte) |
7d049f3a | 6901 | goto out_unlock; |
57a196a5 MK |
6902 | |
6903 | ptl = huge_pte_lock(h, mm, pte); | |
6904 | entry = huge_ptep_get(pte); | |
6905 | if (pte_present(entry)) { | |
458568c9 PX |
6906 | page = pte_page(entry); |
6907 | ||
6908 | if (!huge_pte_write(entry)) { | |
6909 | if (flags & FOLL_WRITE) { | |
6910 | page = NULL; | |
6911 | goto out; | |
6912 | } | |
6913 | ||
6914 | if (gup_must_unshare(vma, flags, page)) { | |
6915 | /* Tell the caller to do unsharing */ | |
6916 | page = ERR_PTR(-EMLINK); | |
6917 | goto out; | |
6918 | } | |
6919 | } | |
6920 | ||
426056ef | 6921 | page = nth_page(page, ((address & ~huge_page_mask(h)) >> PAGE_SHIFT)); |
458568c9 | 6922 | |
57a196a5 MK |
6923 | /* |
6924 | * Note that page may be a sub-page, and with vmemmap | |
6925 | * optimizations the page struct may be read only. | |
6926 | * try_grab_page() will increase the ref count on the | |
6927 | * head page, so this will be OK. | |
6928 | * | |
e2ca6ba6 LT |
6929 | * try_grab_page() should always be able to get the page here, |
6930 | * because we hold the ptl lock and have verified pte_present(). | |
57a196a5 | 6931 | */ |
458568c9 PX |
6932 | ret = try_grab_page(page, flags); |
6933 | ||
6934 | if (WARN_ON_ONCE(ret)) { | |
6935 | page = ERR_PTR(ret); | |
57a196a5 MK |
6936 | goto out; |
6937 | } | |
5502ea44 PX |
6938 | |
6939 | *page_mask = (1U << huge_page_order(h)) - 1; | |
57a196a5 MK |
6940 | } |
6941 | out: | |
6942 | spin_unlock(ptl); | |
7d049f3a PX |
6943 | out_unlock: |
6944 | hugetlb_vma_unlock_read(vma); | |
dd767aaa PX |
6945 | |
6946 | /* | |
6947 | * Fixup retval for dump requests: if pagecache doesn't exist, | |
6948 | * don't try to allocate a new page but just skip it. | |
6949 | */ | |
6950 | if (!page && (flags & FOLL_DUMP) && | |
6951 | !hugetlbfs_pagecache_present(h, vma, address)) | |
6952 | page = ERR_PTR(-EFAULT); | |
6953 | ||
57a196a5 MK |
6954 | return page; |
6955 | } | |
6956 | ||
a79390f5 | 6957 | long hugetlb_change_protection(struct vm_area_struct *vma, |
5a90d5a1 PX |
6958 | unsigned long address, unsigned long end, |
6959 | pgprot_t newprot, unsigned long cp_flags) | |
8f860591 ZY |
6960 | { |
6961 | struct mm_struct *mm = vma->vm_mm; | |
6962 | unsigned long start = address; | |
6963 | pte_t *ptep; | |
6964 | pte_t pte; | |
a5516438 | 6965 | struct hstate *h = hstate_vma(vma); |
a79390f5 | 6966 | long pages = 0, psize = huge_page_size(h); |
dff11abe | 6967 | bool shared_pmd = false; |
ac46d4f3 | 6968 | struct mmu_notifier_range range; |
e95a9851 | 6969 | unsigned long last_addr_mask; |
5a90d5a1 PX |
6970 | bool uffd_wp = cp_flags & MM_CP_UFFD_WP; |
6971 | bool uffd_wp_resolve = cp_flags & MM_CP_UFFD_WP_RESOLVE; | |
dff11abe MK |
6972 | |
6973 | /* | |
6974 | * In the case of shared PMDs, the area to flush could be beyond | |
ac46d4f3 | 6975 | * start/end. Set range.start/range.end to cover the maximum possible |
dff11abe MK |
6976 | * range if PMD sharing is possible. |
6977 | */ | |
7269f999 | 6978 | mmu_notifier_range_init(&range, MMU_NOTIFY_PROTECTION_VMA, |
7d4a8be0 | 6979 | 0, mm, start, end); |
ac46d4f3 | 6980 | adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end); |
8f860591 ZY |
6981 | |
6982 | BUG_ON(address >= end); | |
ac46d4f3 | 6983 | flush_cache_range(vma, range.start, range.end); |
8f860591 | 6984 | |
ac46d4f3 | 6985 | mmu_notifier_invalidate_range_start(&range); |
40549ba8 | 6986 | hugetlb_vma_lock_write(vma); |
83cde9e8 | 6987 | i_mmap_lock_write(vma->vm_file->f_mapping); |
40549ba8 | 6988 | last_addr_mask = hugetlb_mask_last_page(h); |
60dfaad6 | 6989 | for (; address < end; address += psize) { |
cb900f41 | 6990 | spinlock_t *ptl; |
9c67a207 | 6991 | ptep = hugetlb_walk(vma, address, psize); |
e95a9851 | 6992 | if (!ptep) { |
fed15f13 PX |
6993 | if (!uffd_wp) { |
6994 | address |= last_addr_mask; | |
6995 | continue; | |
6996 | } | |
6997 | /* | |
6998 | * Userfaultfd wr-protect requires pgtable | |
6999 | * pre-allocations to install pte markers. | |
7000 | */ | |
7001 | ptep = huge_pte_alloc(mm, vma, address, psize); | |
d1751118 PX |
7002 | if (!ptep) { |
7003 | pages = -ENOMEM; | |
fed15f13 | 7004 | break; |
d1751118 | 7005 | } |
e95a9851 | 7006 | } |
cb900f41 | 7007 | ptl = huge_pte_lock(h, mm, ptep); |
4ddb4d91 | 7008 | if (huge_pmd_unshare(mm, vma, address, ptep)) { |
60dfaad6 PX |
7009 | /* |
7010 | * When uffd-wp is enabled on the vma, unshare | |
7011 | * shouldn't happen at all. Warn about it if it | |
7012 | * happened due to some reason. | |
7013 | */ | |
7014 | WARN_ON_ONCE(uffd_wp || uffd_wp_resolve); | |
7da4d641 | 7015 | pages++; |
cb900f41 | 7016 | spin_unlock(ptl); |
dff11abe | 7017 | shared_pmd = true; |
4ddb4d91 | 7018 | address |= last_addr_mask; |
39dde65c | 7019 | continue; |
7da4d641 | 7020 | } |
a8bda28d NH |
7021 | pte = huge_ptep_get(ptep); |
7022 | if (unlikely(is_hugetlb_entry_hwpoisoned(pte))) { | |
0e678153 DH |
7023 | /* Nothing to do. */ |
7024 | } else if (unlikely(is_hugetlb_entry_migration(pte))) { | |
a8bda28d | 7025 | swp_entry_t entry = pte_to_swp_entry(pte); |
6c287605 | 7026 | struct page *page = pfn_swap_entry_to_page(entry); |
44f86392 | 7027 | pte_t newpte = pte; |
a8bda28d | 7028 | |
44f86392 | 7029 | if (is_writable_migration_entry(entry)) { |
6c287605 DH |
7030 | if (PageAnon(page)) |
7031 | entry = make_readable_exclusive_migration_entry( | |
7032 | swp_offset(entry)); | |
7033 | else | |
7034 | entry = make_readable_migration_entry( | |
7035 | swp_offset(entry)); | |
a8bda28d | 7036 | newpte = swp_entry_to_pte(entry); |
a8bda28d NH |
7037 | pages++; |
7038 | } | |
44f86392 DH |
7039 | |
7040 | if (uffd_wp) | |
7041 | newpte = pte_swp_mkuffd_wp(newpte); | |
7042 | else if (uffd_wp_resolve) | |
7043 | newpte = pte_swp_clear_uffd_wp(newpte); | |
7044 | if (!pte_same(pte, newpte)) | |
935d4f0c | 7045 | set_huge_pte_at(mm, address, ptep, newpte, psize); |
0e678153 | 7046 | } else if (unlikely(is_pte_marker(pte))) { |
c5977c95 PX |
7047 | /* |
7048 | * Do nothing on a poison marker; page is | |
7049 | * corrupted, permissons do not apply. Here | |
7050 | * pte_marker_uffd_wp()==true implies !poison | |
7051 | * because they're mutual exclusive. | |
7052 | */ | |
7053 | if (pte_marker_uffd_wp(pte) && uffd_wp_resolve) | |
0e678153 | 7054 | /* Safe to modify directly (non-present->none). */ |
60dfaad6 | 7055 | huge_pte_clear(mm, address, ptep, psize); |
0e678153 | 7056 | } else if (!huge_pte_none(pte)) { |
023bdd00 | 7057 | pte_t old_pte; |
79c1c594 | 7058 | unsigned int shift = huge_page_shift(hstate_vma(vma)); |
023bdd00 AK |
7059 | |
7060 | old_pte = huge_ptep_modify_prot_start(vma, address, ptep); | |
16785bd7 | 7061 | pte = huge_pte_modify(old_pte, newprot); |
79c1c594 | 7062 | pte = arch_make_huge_pte(pte, shift, vma->vm_flags); |
5a90d5a1 | 7063 | if (uffd_wp) |
f1eb1bac | 7064 | pte = huge_pte_mkuffd_wp(pte); |
5a90d5a1 PX |
7065 | else if (uffd_wp_resolve) |
7066 | pte = huge_pte_clear_uffd_wp(pte); | |
023bdd00 | 7067 | huge_ptep_modify_prot_commit(vma, address, ptep, old_pte, pte); |
7da4d641 | 7068 | pages++; |
60dfaad6 PX |
7069 | } else { |
7070 | /* None pte */ | |
7071 | if (unlikely(uffd_wp)) | |
7072 | /* Safe to modify directly (none->non-present). */ | |
7073 | set_huge_pte_at(mm, address, ptep, | |
935d4f0c RR |
7074 | make_pte_marker(PTE_MARKER_UFFD_WP), |
7075 | psize); | |
8f860591 | 7076 | } |
cb900f41 | 7077 | spin_unlock(ptl); |
8f860591 | 7078 | } |
d833352a | 7079 | /* |
c8c06efa | 7080 | * Must flush TLB before releasing i_mmap_rwsem: x86's huge_pmd_unshare |
d833352a | 7081 | * may have cleared our pud entry and done put_page on the page table: |
c8c06efa | 7082 | * once we release i_mmap_rwsem, another task can do the final put_page |
dff11abe MK |
7083 | * and that page table be reused and filled with junk. If we actually |
7084 | * did unshare a page of pmds, flush the range corresponding to the pud. | |
d833352a | 7085 | */ |
dff11abe | 7086 | if (shared_pmd) |
ac46d4f3 | 7087 | flush_hugetlb_tlb_range(vma, range.start, range.end); |
dff11abe MK |
7088 | else |
7089 | flush_hugetlb_tlb_range(vma, start, end); | |
0f10851e | 7090 | /* |
1af5a810 AP |
7091 | * No need to call mmu_notifier_arch_invalidate_secondary_tlbs() we are |
7092 | * downgrading page table protection not changing it to point to a new | |
7093 | * page. | |
0f10851e | 7094 | * |
ee65728e | 7095 | * See Documentation/mm/mmu_notifier.rst |
0f10851e | 7096 | */ |
83cde9e8 | 7097 | i_mmap_unlock_write(vma->vm_file->f_mapping); |
40549ba8 | 7098 | hugetlb_vma_unlock_write(vma); |
ac46d4f3 | 7099 | mmu_notifier_invalidate_range_end(&range); |
7da4d641 | 7100 | |
d1751118 | 7101 | return pages > 0 ? (pages << h->order) : pages; |
8f860591 ZY |
7102 | } |
7103 | ||
33b8f84a MK |
7104 | /* Return true if reservation was successful, false otherwise. */ |
7105 | bool hugetlb_reserve_pages(struct inode *inode, | |
a1e78772 | 7106 | long from, long to, |
5a6fe125 | 7107 | struct vm_area_struct *vma, |
ca16d140 | 7108 | vm_flags_t vm_flags) |
e4e574b7 | 7109 | { |
c5094ec7 | 7110 | long chg = -1, add = -1; |
a5516438 | 7111 | struct hstate *h = hstate_inode(inode); |
90481622 | 7112 | struct hugepage_subpool *spool = subpool_inode(inode); |
9119a41e | 7113 | struct resv_map *resv_map; |
075a61d0 | 7114 | struct hugetlb_cgroup *h_cg = NULL; |
0db9d74e | 7115 | long gbl_reserve, regions_needed = 0; |
e4e574b7 | 7116 | |
63489f8e MK |
7117 | /* This should never happen */ |
7118 | if (from > to) { | |
7119 | VM_WARN(1, "%s called with a negative range\n", __func__); | |
33b8f84a | 7120 | return false; |
63489f8e MK |
7121 | } |
7122 | ||
8d9bfb26 | 7123 | /* |
e700898f MK |
7124 | * vma specific semaphore used for pmd sharing and fault/truncation |
7125 | * synchronization | |
8d9bfb26 MK |
7126 | */ |
7127 | hugetlb_vma_lock_alloc(vma); | |
7128 | ||
17c9d12e MG |
7129 | /* |
7130 | * Only apply hugepage reservation if asked. At fault time, an | |
7131 | * attempt will be made for VM_NORESERVE to allocate a page | |
90481622 | 7132 | * without using reserves |
17c9d12e | 7133 | */ |
ca16d140 | 7134 | if (vm_flags & VM_NORESERVE) |
33b8f84a | 7135 | return true; |
17c9d12e | 7136 | |
a1e78772 MG |
7137 | /* |
7138 | * Shared mappings base their reservation on the number of pages that | |
7139 | * are already allocated on behalf of the file. Private mappings need | |
7140 | * to reserve the full area even if read-only as mprotect() may be | |
7141 | * called to make the mapping read-write. Assume !vma is a shm mapping | |
7142 | */ | |
9119a41e | 7143 | if (!vma || vma->vm_flags & VM_MAYSHARE) { |
f27a5136 MK |
7144 | /* |
7145 | * resv_map can not be NULL as hugetlb_reserve_pages is only | |
7146 | * called for inodes for which resv_maps were created (see | |
7147 | * hugetlbfs_get_inode). | |
7148 | */ | |
4e35f483 | 7149 | resv_map = inode_resv_map(inode); |
9119a41e | 7150 | |
0db9d74e | 7151 | chg = region_chg(resv_map, from, to, ®ions_needed); |
9119a41e | 7152 | } else { |
e9fe92ae | 7153 | /* Private mapping. */ |
9119a41e | 7154 | resv_map = resv_map_alloc(); |
17c9d12e | 7155 | if (!resv_map) |
8d9bfb26 | 7156 | goto out_err; |
17c9d12e | 7157 | |
a1e78772 | 7158 | chg = to - from; |
84afd99b | 7159 | |
17c9d12e MG |
7160 | set_vma_resv_map(vma, resv_map); |
7161 | set_vma_resv_flags(vma, HPAGE_RESV_OWNER); | |
7162 | } | |
7163 | ||
33b8f84a | 7164 | if (chg < 0) |
c50ac050 | 7165 | goto out_err; |
8a630112 | 7166 | |
33b8f84a MK |
7167 | if (hugetlb_cgroup_charge_cgroup_rsvd(hstate_index(h), |
7168 | chg * pages_per_huge_page(h), &h_cg) < 0) | |
075a61d0 | 7169 | goto out_err; |
075a61d0 MA |
7170 | |
7171 | if (vma && !(vma->vm_flags & VM_MAYSHARE) && h_cg) { | |
7172 | /* For private mappings, the hugetlb_cgroup uncharge info hangs | |
7173 | * of the resv_map. | |
7174 | */ | |
7175 | resv_map_set_hugetlb_cgroup_uncharge_info(resv_map, h_cg, h); | |
7176 | } | |
7177 | ||
1c5ecae3 MK |
7178 | /* |
7179 | * There must be enough pages in the subpool for the mapping. If | |
7180 | * the subpool has a minimum size, there may be some global | |
7181 | * reservations already in place (gbl_reserve). | |
7182 | */ | |
7183 | gbl_reserve = hugepage_subpool_get_pages(spool, chg); | |
33b8f84a | 7184 | if (gbl_reserve < 0) |
075a61d0 | 7185 | goto out_uncharge_cgroup; |
5a6fe125 MG |
7186 | |
7187 | /* | |
17c9d12e | 7188 | * Check enough hugepages are available for the reservation. |
90481622 | 7189 | * Hand the pages back to the subpool if there are not |
5a6fe125 | 7190 | */ |
33b8f84a | 7191 | if (hugetlb_acct_memory(h, gbl_reserve) < 0) |
075a61d0 | 7192 | goto out_put_pages; |
17c9d12e MG |
7193 | |
7194 | /* | |
7195 | * Account for the reservations made. Shared mappings record regions | |
7196 | * that have reservations as they are shared by multiple VMAs. | |
7197 | * When the last VMA disappears, the region map says how much | |
7198 | * the reservation was and the page cache tells how much of | |
7199 | * the reservation was consumed. Private mappings are per-VMA and | |
7200 | * only the consumed reservations are tracked. When the VMA | |
7201 | * disappears, the original reservation is the VMA size and the | |
7202 | * consumed reservations are stored in the map. Hence, nothing | |
7203 | * else has to be done for private mappings here | |
7204 | */ | |
33039678 | 7205 | if (!vma || vma->vm_flags & VM_MAYSHARE) { |
075a61d0 | 7206 | add = region_add(resv_map, from, to, regions_needed, h, h_cg); |
0db9d74e MA |
7207 | |
7208 | if (unlikely(add < 0)) { | |
7209 | hugetlb_acct_memory(h, -gbl_reserve); | |
075a61d0 | 7210 | goto out_put_pages; |
0db9d74e | 7211 | } else if (unlikely(chg > add)) { |
33039678 MK |
7212 | /* |
7213 | * pages in this range were added to the reserve | |
7214 | * map between region_chg and region_add. This | |
d0ce0e47 | 7215 | * indicates a race with alloc_hugetlb_folio. Adjust |
33039678 MK |
7216 | * the subpool and reserve counts modified above |
7217 | * based on the difference. | |
7218 | */ | |
7219 | long rsv_adjust; | |
7220 | ||
d85aecf2 ML |
7221 | /* |
7222 | * hugetlb_cgroup_uncharge_cgroup_rsvd() will put the | |
7223 | * reference to h_cg->css. See comment below for detail. | |
7224 | */ | |
075a61d0 MA |
7225 | hugetlb_cgroup_uncharge_cgroup_rsvd( |
7226 | hstate_index(h), | |
7227 | (chg - add) * pages_per_huge_page(h), h_cg); | |
7228 | ||
33039678 MK |
7229 | rsv_adjust = hugepage_subpool_put_pages(spool, |
7230 | chg - add); | |
7231 | hugetlb_acct_memory(h, -rsv_adjust); | |
d85aecf2 ML |
7232 | } else if (h_cg) { |
7233 | /* | |
7234 | * The file_regions will hold their own reference to | |
7235 | * h_cg->css. So we should release the reference held | |
7236 | * via hugetlb_cgroup_charge_cgroup_rsvd() when we are | |
7237 | * done. | |
7238 | */ | |
7239 | hugetlb_cgroup_put_rsvd_cgroup(h_cg); | |
33039678 MK |
7240 | } |
7241 | } | |
33b8f84a MK |
7242 | return true; |
7243 | ||
075a61d0 MA |
7244 | out_put_pages: |
7245 | /* put back original number of pages, chg */ | |
7246 | (void)hugepage_subpool_put_pages(spool, chg); | |
7247 | out_uncharge_cgroup: | |
7248 | hugetlb_cgroup_uncharge_cgroup_rsvd(hstate_index(h), | |
7249 | chg * pages_per_huge_page(h), h_cg); | |
c50ac050 | 7250 | out_err: |
8d9bfb26 | 7251 | hugetlb_vma_lock_free(vma); |
5e911373 | 7252 | if (!vma || vma->vm_flags & VM_MAYSHARE) |
0db9d74e MA |
7253 | /* Only call region_abort if the region_chg succeeded but the |
7254 | * region_add failed or didn't run. | |
7255 | */ | |
7256 | if (chg >= 0 && add < 0) | |
7257 | region_abort(resv_map, from, to, regions_needed); | |
92fe9dcb | 7258 | if (vma && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { |
f031dd27 | 7259 | kref_put(&resv_map->refs, resv_map_release); |
92fe9dcb RR |
7260 | set_vma_resv_map(vma, NULL); |
7261 | } | |
33b8f84a | 7262 | return false; |
a43a8c39 CK |
7263 | } |
7264 | ||
b5cec28d MK |
7265 | long hugetlb_unreserve_pages(struct inode *inode, long start, long end, |
7266 | long freed) | |
a43a8c39 | 7267 | { |
a5516438 | 7268 | struct hstate *h = hstate_inode(inode); |
4e35f483 | 7269 | struct resv_map *resv_map = inode_resv_map(inode); |
9119a41e | 7270 | long chg = 0; |
90481622 | 7271 | struct hugepage_subpool *spool = subpool_inode(inode); |
1c5ecae3 | 7272 | long gbl_reserve; |
45c682a6 | 7273 | |
f27a5136 MK |
7274 | /* |
7275 | * Since this routine can be called in the evict inode path for all | |
7276 | * hugetlbfs inodes, resv_map could be NULL. | |
7277 | */ | |
b5cec28d MK |
7278 | if (resv_map) { |
7279 | chg = region_del(resv_map, start, end); | |
7280 | /* | |
7281 | * region_del() can fail in the rare case where a region | |
7282 | * must be split and another region descriptor can not be | |
7283 | * allocated. If end == LONG_MAX, it will not fail. | |
7284 | */ | |
7285 | if (chg < 0) | |
7286 | return chg; | |
7287 | } | |
7288 | ||
45c682a6 | 7289 | spin_lock(&inode->i_lock); |
e4c6f8be | 7290 | inode->i_blocks -= (blocks_per_huge_page(h) * freed); |
45c682a6 KC |
7291 | spin_unlock(&inode->i_lock); |
7292 | ||
1c5ecae3 MK |
7293 | /* |
7294 | * If the subpool has a minimum size, the number of global | |
7295 | * reservations to be released may be adjusted. | |
dddf31a4 ML |
7296 | * |
7297 | * Note that !resv_map implies freed == 0. So (chg - freed) | |
7298 | * won't go negative. | |
1c5ecae3 MK |
7299 | */ |
7300 | gbl_reserve = hugepage_subpool_put_pages(spool, (chg - freed)); | |
7301 | hugetlb_acct_memory(h, -gbl_reserve); | |
b5cec28d MK |
7302 | |
7303 | return 0; | |
a43a8c39 | 7304 | } |
93f70f90 | 7305 | |
3212b535 SC |
7306 | #ifdef CONFIG_ARCH_WANT_HUGE_PMD_SHARE |
7307 | static unsigned long page_table_shareable(struct vm_area_struct *svma, | |
7308 | struct vm_area_struct *vma, | |
7309 | unsigned long addr, pgoff_t idx) | |
7310 | { | |
7311 | unsigned long saddr = ((idx - svma->vm_pgoff) << PAGE_SHIFT) + | |
7312 | svma->vm_start; | |
7313 | unsigned long sbase = saddr & PUD_MASK; | |
7314 | unsigned long s_end = sbase + PUD_SIZE; | |
7315 | ||
7316 | /* Allow segments to share if only one is marked locked */ | |
e430a95a SB |
7317 | unsigned long vm_flags = vma->vm_flags & ~VM_LOCKED_MASK; |
7318 | unsigned long svm_flags = svma->vm_flags & ~VM_LOCKED_MASK; | |
3212b535 SC |
7319 | |
7320 | /* | |
7321 | * match the virtual addresses, permission and the alignment of the | |
7322 | * page table page. | |
131a79b4 MK |
7323 | * |
7324 | * Also, vma_lock (vm_private_data) is required for sharing. | |
3212b535 SC |
7325 | */ |
7326 | if (pmd_index(addr) != pmd_index(saddr) || | |
7327 | vm_flags != svm_flags || | |
131a79b4 MK |
7328 | !range_in_vma(svma, sbase, s_end) || |
7329 | !svma->vm_private_data) | |
3212b535 SC |
7330 | return 0; |
7331 | ||
7332 | return saddr; | |
7333 | } | |
7334 | ||
bbff39cc | 7335 | bool want_pmd_share(struct vm_area_struct *vma, unsigned long addr) |
3212b535 | 7336 | { |
bbff39cc MK |
7337 | unsigned long start = addr & PUD_MASK; |
7338 | unsigned long end = start + PUD_SIZE; | |
7339 | ||
8d9bfb26 MK |
7340 | #ifdef CONFIG_USERFAULTFD |
7341 | if (uffd_disable_huge_pmd_share(vma)) | |
7342 | return false; | |
7343 | #endif | |
3212b535 SC |
7344 | /* |
7345 | * check on proper vm_flags and page table alignment | |
7346 | */ | |
8d9bfb26 MK |
7347 | if (!(vma->vm_flags & VM_MAYSHARE)) |
7348 | return false; | |
bbff39cc | 7349 | if (!vma->vm_private_data) /* vma lock required for sharing */ |
8d9bfb26 MK |
7350 | return false; |
7351 | if (!range_in_vma(vma, start, end)) | |
7352 | return false; | |
7353 | return true; | |
7354 | } | |
7355 | ||
017b1660 MK |
7356 | /* |
7357 | * Determine if start,end range within vma could be mapped by shared pmd. | |
7358 | * If yes, adjust start and end to cover range associated with possible | |
7359 | * shared pmd mappings. | |
7360 | */ | |
7361 | void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma, | |
7362 | unsigned long *start, unsigned long *end) | |
7363 | { | |
a1ba9da8 LX |
7364 | unsigned long v_start = ALIGN(vma->vm_start, PUD_SIZE), |
7365 | v_end = ALIGN_DOWN(vma->vm_end, PUD_SIZE); | |
017b1660 | 7366 | |
a1ba9da8 | 7367 | /* |
f0953a1b IM |
7368 | * vma needs to span at least one aligned PUD size, and the range |
7369 | * must be at least partially within in. | |
a1ba9da8 LX |
7370 | */ |
7371 | if (!(vma->vm_flags & VM_MAYSHARE) || !(v_end > v_start) || | |
7372 | (*end <= v_start) || (*start >= v_end)) | |
017b1660 MK |
7373 | return; |
7374 | ||
75802ca6 | 7375 | /* Extend the range to be PUD aligned for a worst case scenario */ |
a1ba9da8 LX |
7376 | if (*start > v_start) |
7377 | *start = ALIGN_DOWN(*start, PUD_SIZE); | |
017b1660 | 7378 | |
a1ba9da8 LX |
7379 | if (*end < v_end) |
7380 | *end = ALIGN(*end, PUD_SIZE); | |
017b1660 MK |
7381 | } |
7382 | ||
3212b535 SC |
7383 | /* |
7384 | * Search for a shareable pmd page for hugetlb. In any case calls pmd_alloc() | |
7385 | * and returns the corresponding pte. While this is not necessary for the | |
7386 | * !shared pmd case because we can allocate the pmd later as well, it makes the | |
3a47c54f MK |
7387 | * code much cleaner. pmd allocation is essential for the shared case because |
7388 | * pud has to be populated inside the same i_mmap_rwsem section - otherwise | |
7389 | * racing tasks could either miss the sharing (see huge_pte_offset) or select a | |
7390 | * bad pmd for sharing. | |
3212b535 | 7391 | */ |
aec44e0f PX |
7392 | pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma, |
7393 | unsigned long addr, pud_t *pud) | |
3212b535 | 7394 | { |
3212b535 SC |
7395 | struct address_space *mapping = vma->vm_file->f_mapping; |
7396 | pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) + | |
7397 | vma->vm_pgoff; | |
7398 | struct vm_area_struct *svma; | |
7399 | unsigned long saddr; | |
7400 | pte_t *spte = NULL; | |
7401 | pte_t *pte; | |
7402 | ||
3a47c54f | 7403 | i_mmap_lock_read(mapping); |
3212b535 SC |
7404 | vma_interval_tree_foreach(svma, &mapping->i_mmap, idx, idx) { |
7405 | if (svma == vma) | |
7406 | continue; | |
7407 | ||
7408 | saddr = page_table_shareable(svma, vma, addr, idx); | |
7409 | if (saddr) { | |
9c67a207 PX |
7410 | spte = hugetlb_walk(svma, saddr, |
7411 | vma_mmu_pagesize(svma)); | |
3212b535 SC |
7412 | if (spte) { |
7413 | get_page(virt_to_page(spte)); | |
7414 | break; | |
7415 | } | |
7416 | } | |
7417 | } | |
7418 | ||
7419 | if (!spte) | |
7420 | goto out; | |
7421 | ||
349d1670 | 7422 | spin_lock(&mm->page_table_lock); |
dc6c9a35 | 7423 | if (pud_none(*pud)) { |
3212b535 SC |
7424 | pud_populate(mm, pud, |
7425 | (pmd_t *)((unsigned long)spte & PAGE_MASK)); | |
c17b1f42 | 7426 | mm_inc_nr_pmds(mm); |
dc6c9a35 | 7427 | } else { |
3212b535 | 7428 | put_page(virt_to_page(spte)); |
dc6c9a35 | 7429 | } |
349d1670 | 7430 | spin_unlock(&mm->page_table_lock); |
3212b535 SC |
7431 | out: |
7432 | pte = (pte_t *)pmd_alloc(mm, pud, addr); | |
3a47c54f | 7433 | i_mmap_unlock_read(mapping); |
3212b535 SC |
7434 | return pte; |
7435 | } | |
7436 | ||
7437 | /* | |
7438 | * unmap huge page backed by shared pte. | |
7439 | * | |
7440 | * Hugetlb pte page is ref counted at the time of mapping. If pte is shared | |
7441 | * indicated by page_count > 1, unmap is achieved by clearing pud and | |
7442 | * decrementing the ref count. If count == 1, the pte page is not shared. | |
7443 | * | |
3a47c54f | 7444 | * Called with page table lock held. |
3212b535 SC |
7445 | * |
7446 | * returns: 1 successfully unmapped a shared pte page | |
7447 | * 0 the underlying pte page is not shared, or it is the last user | |
7448 | */ | |
34ae204f | 7449 | int huge_pmd_unshare(struct mm_struct *mm, struct vm_area_struct *vma, |
4ddb4d91 | 7450 | unsigned long addr, pte_t *ptep) |
3212b535 | 7451 | { |
4ddb4d91 MK |
7452 | pgd_t *pgd = pgd_offset(mm, addr); |
7453 | p4d_t *p4d = p4d_offset(pgd, addr); | |
7454 | pud_t *pud = pud_offset(p4d, addr); | |
3212b535 | 7455 | |
34ae204f | 7456 | i_mmap_assert_write_locked(vma->vm_file->f_mapping); |
40549ba8 | 7457 | hugetlb_vma_assert_locked(vma); |
3212b535 SC |
7458 | BUG_ON(page_count(virt_to_page(ptep)) == 0); |
7459 | if (page_count(virt_to_page(ptep)) == 1) | |
7460 | return 0; | |
7461 | ||
7462 | pud_clear(pud); | |
7463 | put_page(virt_to_page(ptep)); | |
dc6c9a35 | 7464 | mm_dec_nr_pmds(mm); |
3212b535 SC |
7465 | return 1; |
7466 | } | |
c1991e07 | 7467 | |
9e5fc74c | 7468 | #else /* !CONFIG_ARCH_WANT_HUGE_PMD_SHARE */ |
8d9bfb26 | 7469 | |
aec44e0f PX |
7470 | pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma, |
7471 | unsigned long addr, pud_t *pud) | |
9e5fc74c SC |
7472 | { |
7473 | return NULL; | |
7474 | } | |
e81f2d22 | 7475 | |
34ae204f | 7476 | int huge_pmd_unshare(struct mm_struct *mm, struct vm_area_struct *vma, |
4ddb4d91 | 7477 | unsigned long addr, pte_t *ptep) |
e81f2d22 ZZ |
7478 | { |
7479 | return 0; | |
7480 | } | |
017b1660 MK |
7481 | |
7482 | void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma, | |
7483 | unsigned long *start, unsigned long *end) | |
7484 | { | |
7485 | } | |
c1991e07 PX |
7486 | |
7487 | bool want_pmd_share(struct vm_area_struct *vma, unsigned long addr) | |
7488 | { | |
7489 | return false; | |
7490 | } | |
3212b535 SC |
7491 | #endif /* CONFIG_ARCH_WANT_HUGE_PMD_SHARE */ |
7492 | ||
9e5fc74c | 7493 | #ifdef CONFIG_ARCH_WANT_GENERAL_HUGETLB |
aec44e0f | 7494 | pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, |
9e5fc74c SC |
7495 | unsigned long addr, unsigned long sz) |
7496 | { | |
7497 | pgd_t *pgd; | |
c2febafc | 7498 | p4d_t *p4d; |
9e5fc74c SC |
7499 | pud_t *pud; |
7500 | pte_t *pte = NULL; | |
7501 | ||
7502 | pgd = pgd_offset(mm, addr); | |
f4f0a3d8 KS |
7503 | p4d = p4d_alloc(mm, pgd, addr); |
7504 | if (!p4d) | |
7505 | return NULL; | |
c2febafc | 7506 | pud = pud_alloc(mm, p4d, addr); |
9e5fc74c SC |
7507 | if (pud) { |
7508 | if (sz == PUD_SIZE) { | |
7509 | pte = (pte_t *)pud; | |
7510 | } else { | |
7511 | BUG_ON(sz != PMD_SIZE); | |
c1991e07 | 7512 | if (want_pmd_share(vma, addr) && pud_none(*pud)) |
aec44e0f | 7513 | pte = huge_pmd_share(mm, vma, addr, pud); |
9e5fc74c SC |
7514 | else |
7515 | pte = (pte_t *)pmd_alloc(mm, pud, addr); | |
7516 | } | |
7517 | } | |
191fcdb6 JH |
7518 | |
7519 | if (pte) { | |
7520 | pte_t pteval = ptep_get_lockless(pte); | |
7521 | ||
7522 | BUG_ON(pte_present(pteval) && !pte_huge(pteval)); | |
7523 | } | |
9e5fc74c SC |
7524 | |
7525 | return pte; | |
7526 | } | |
7527 | ||
9b19df29 PA |
7528 | /* |
7529 | * huge_pte_offset() - Walk the page table to resolve the hugepage | |
7530 | * entry at address @addr | |
7531 | * | |
8ac0b81a LX |
7532 | * Return: Pointer to page table entry (PUD or PMD) for |
7533 | * address @addr, or NULL if a !p*d_present() entry is encountered and the | |
9b19df29 PA |
7534 | * size @sz doesn't match the hugepage size at this level of the page |
7535 | * table. | |
7536 | */ | |
7868a208 PA |
7537 | pte_t *huge_pte_offset(struct mm_struct *mm, |
7538 | unsigned long addr, unsigned long sz) | |
9e5fc74c SC |
7539 | { |
7540 | pgd_t *pgd; | |
c2febafc | 7541 | p4d_t *p4d; |
8ac0b81a LX |
7542 | pud_t *pud; |
7543 | pmd_t *pmd; | |
9e5fc74c SC |
7544 | |
7545 | pgd = pgd_offset(mm, addr); | |
c2febafc KS |
7546 | if (!pgd_present(*pgd)) |
7547 | return NULL; | |
7548 | p4d = p4d_offset(pgd, addr); | |
7549 | if (!p4d_present(*p4d)) | |
7550 | return NULL; | |
9b19df29 | 7551 | |
c2febafc | 7552 | pud = pud_offset(p4d, addr); |
8ac0b81a LX |
7553 | if (sz == PUD_SIZE) |
7554 | /* must be pud huge, non-present or none */ | |
c2febafc | 7555 | return (pte_t *)pud; |
8ac0b81a | 7556 | if (!pud_present(*pud)) |
9b19df29 | 7557 | return NULL; |
8ac0b81a | 7558 | /* must have a valid entry and size to go further */ |
9b19df29 | 7559 | |
8ac0b81a LX |
7560 | pmd = pmd_offset(pud, addr); |
7561 | /* must be pmd huge, non-present or none */ | |
7562 | return (pte_t *)pmd; | |
9e5fc74c SC |
7563 | } |
7564 | ||
e95a9851 MK |
7565 | /* |
7566 | * Return a mask that can be used to update an address to the last huge | |
7567 | * page in a page table page mapping size. Used to skip non-present | |
7568 | * page table entries when linearly scanning address ranges. Architectures | |
7569 | * with unique huge page to page table relationships can define their own | |
7570 | * version of this routine. | |
7571 | */ | |
7572 | unsigned long hugetlb_mask_last_page(struct hstate *h) | |
7573 | { | |
7574 | unsigned long hp_size = huge_page_size(h); | |
7575 | ||
7576 | if (hp_size == PUD_SIZE) | |
7577 | return P4D_SIZE - PUD_SIZE; | |
7578 | else if (hp_size == PMD_SIZE) | |
7579 | return PUD_SIZE - PMD_SIZE; | |
7580 | else | |
7581 | return 0UL; | |
7582 | } | |
7583 | ||
7584 | #else | |
7585 | ||
7586 | /* See description above. Architectures can provide their own version. */ | |
7587 | __weak unsigned long hugetlb_mask_last_page(struct hstate *h) | |
7588 | { | |
4ddb4d91 MK |
7589 | #ifdef CONFIG_ARCH_WANT_HUGE_PMD_SHARE |
7590 | if (huge_page_size(h) == PMD_SIZE) | |
7591 | return PUD_SIZE - PMD_SIZE; | |
7592 | #endif | |
e95a9851 MK |
7593 | return 0UL; |
7594 | } | |
7595 | ||
61f77eda NH |
7596 | #endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */ |
7597 | ||
7598 | /* | |
7599 | * These functions are overwritable if your architecture needs its own | |
7600 | * behavior. | |
7601 | */ | |
9747b9e9 | 7602 | bool isolate_hugetlb(struct folio *folio, struct list_head *list) |
31caf665 | 7603 | { |
9747b9e9 | 7604 | bool ret = true; |
bcc54222 | 7605 | |
db71ef79 | 7606 | spin_lock_irq(&hugetlb_lock); |
6aa3a920 SK |
7607 | if (!folio_test_hugetlb(folio) || |
7608 | !folio_test_hugetlb_migratable(folio) || | |
7609 | !folio_try_get(folio)) { | |
9747b9e9 | 7610 | ret = false; |
bcc54222 NH |
7611 | goto unlock; |
7612 | } | |
6aa3a920 SK |
7613 | folio_clear_hugetlb_migratable(folio); |
7614 | list_move_tail(&folio->lru, list); | |
bcc54222 | 7615 | unlock: |
db71ef79 | 7616 | spin_unlock_irq(&hugetlb_lock); |
bcc54222 | 7617 | return ret; |
31caf665 NH |
7618 | } |
7619 | ||
04bac040 | 7620 | int get_hwpoison_hugetlb_folio(struct folio *folio, bool *hugetlb, bool unpoison) |
25182f05 NH |
7621 | { |
7622 | int ret = 0; | |
7623 | ||
7624 | *hugetlb = false; | |
7625 | spin_lock_irq(&hugetlb_lock); | |
04bac040 | 7626 | if (folio_test_hugetlb(folio)) { |
25182f05 | 7627 | *hugetlb = true; |
04bac040 | 7628 | if (folio_test_hugetlb_freed(folio)) |
b283d983 | 7629 | ret = 0; |
04bac040 SK |
7630 | else if (folio_test_hugetlb_migratable(folio) || unpoison) |
7631 | ret = folio_try_get(folio); | |
0ed950d1 NH |
7632 | else |
7633 | ret = -EBUSY; | |
25182f05 NH |
7634 | } |
7635 | spin_unlock_irq(&hugetlb_lock); | |
7636 | return ret; | |
7637 | } | |
7638 | ||
e591ef7d NH |
7639 | int get_huge_page_for_hwpoison(unsigned long pfn, int flags, |
7640 | bool *migratable_cleared) | |
405ce051 NH |
7641 | { |
7642 | int ret; | |
7643 | ||
7644 | spin_lock_irq(&hugetlb_lock); | |
e591ef7d | 7645 | ret = __get_huge_page_for_hwpoison(pfn, flags, migratable_cleared); |
405ce051 NH |
7646 | spin_unlock_irq(&hugetlb_lock); |
7647 | return ret; | |
7648 | } | |
7649 | ||
ea8e72f4 | 7650 | void folio_putback_active_hugetlb(struct folio *folio) |
31caf665 | 7651 | { |
db71ef79 | 7652 | spin_lock_irq(&hugetlb_lock); |
ea8e72f4 SK |
7653 | folio_set_hugetlb_migratable(folio); |
7654 | list_move_tail(&folio->lru, &(folio_hstate(folio))->hugepage_activelist); | |
db71ef79 | 7655 | spin_unlock_irq(&hugetlb_lock); |
ea8e72f4 | 7656 | folio_put(folio); |
31caf665 | 7657 | } |
ab5ac90a | 7658 | |
345c62d1 | 7659 | void move_hugetlb_state(struct folio *old_folio, struct folio *new_folio, int reason) |
ab5ac90a | 7660 | { |
345c62d1 | 7661 | struct hstate *h = folio_hstate(old_folio); |
ab5ac90a | 7662 | |
345c62d1 SK |
7663 | hugetlb_cgroup_migrate(old_folio, new_folio); |
7664 | set_page_owner_migrate_reason(&new_folio->page, reason); | |
ab5ac90a MH |
7665 | |
7666 | /* | |
345c62d1 | 7667 | * transfer temporary state of the new hugetlb folio. This is |
ab5ac90a MH |
7668 | * reverse to other transitions because the newpage is going to |
7669 | * be final while the old one will be freed so it takes over | |
7670 | * the temporary status. | |
7671 | * | |
7672 | * Also note that we have to transfer the per-node surplus state | |
7673 | * here as well otherwise the global surplus count will not match | |
7674 | * the per-node's. | |
7675 | */ | |
345c62d1 SK |
7676 | if (folio_test_hugetlb_temporary(new_folio)) { |
7677 | int old_nid = folio_nid(old_folio); | |
7678 | int new_nid = folio_nid(new_folio); | |
7679 | ||
345c62d1 SK |
7680 | folio_set_hugetlb_temporary(old_folio); |
7681 | folio_clear_hugetlb_temporary(new_folio); | |
ab5ac90a | 7682 | |
ab5ac90a | 7683 | |
5af1ab1d ML |
7684 | /* |
7685 | * There is no need to transfer the per-node surplus state | |
7686 | * when we do not cross the node. | |
7687 | */ | |
7688 | if (new_nid == old_nid) | |
7689 | return; | |
db71ef79 | 7690 | spin_lock_irq(&hugetlb_lock); |
ab5ac90a MH |
7691 | if (h->surplus_huge_pages_node[old_nid]) { |
7692 | h->surplus_huge_pages_node[old_nid]--; | |
7693 | h->surplus_huge_pages_node[new_nid]++; | |
7694 | } | |
db71ef79 | 7695 | spin_unlock_irq(&hugetlb_lock); |
ab5ac90a MH |
7696 | } |
7697 | } | |
cf11e85f | 7698 | |
b30c14cd JH |
7699 | static void hugetlb_unshare_pmds(struct vm_area_struct *vma, |
7700 | unsigned long start, | |
7701 | unsigned long end) | |
6dfeaff9 PX |
7702 | { |
7703 | struct hstate *h = hstate_vma(vma); | |
7704 | unsigned long sz = huge_page_size(h); | |
7705 | struct mm_struct *mm = vma->vm_mm; | |
7706 | struct mmu_notifier_range range; | |
b30c14cd | 7707 | unsigned long address; |
6dfeaff9 PX |
7708 | spinlock_t *ptl; |
7709 | pte_t *ptep; | |
7710 | ||
7711 | if (!(vma->vm_flags & VM_MAYSHARE)) | |
7712 | return; | |
7713 | ||
6dfeaff9 PX |
7714 | if (start >= end) |
7715 | return; | |
7716 | ||
9c8bbfac | 7717 | flush_cache_range(vma, start, end); |
6dfeaff9 PX |
7718 | /* |
7719 | * No need to call adjust_range_if_pmd_sharing_possible(), because | |
7720 | * we have already done the PUD_SIZE alignment. | |
7721 | */ | |
7d4a8be0 | 7722 | mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm, |
6dfeaff9 PX |
7723 | start, end); |
7724 | mmu_notifier_invalidate_range_start(&range); | |
40549ba8 | 7725 | hugetlb_vma_lock_write(vma); |
6dfeaff9 PX |
7726 | i_mmap_lock_write(vma->vm_file->f_mapping); |
7727 | for (address = start; address < end; address += PUD_SIZE) { | |
9c67a207 | 7728 | ptep = hugetlb_walk(vma, address, sz); |
6dfeaff9 PX |
7729 | if (!ptep) |
7730 | continue; | |
7731 | ptl = huge_pte_lock(h, mm, ptep); | |
4ddb4d91 | 7732 | huge_pmd_unshare(mm, vma, address, ptep); |
6dfeaff9 PX |
7733 | spin_unlock(ptl); |
7734 | } | |
7735 | flush_hugetlb_tlb_range(vma, start, end); | |
7736 | i_mmap_unlock_write(vma->vm_file->f_mapping); | |
40549ba8 | 7737 | hugetlb_vma_unlock_write(vma); |
6dfeaff9 | 7738 | /* |
1af5a810 | 7739 | * No need to call mmu_notifier_arch_invalidate_secondary_tlbs(), see |
ee65728e | 7740 | * Documentation/mm/mmu_notifier.rst. |
6dfeaff9 PX |
7741 | */ |
7742 | mmu_notifier_invalidate_range_end(&range); | |
7743 | } | |
7744 | ||
b30c14cd JH |
7745 | /* |
7746 | * This function will unconditionally remove all the shared pmd pgtable entries | |
7747 | * within the specific vma for a hugetlbfs memory range. | |
7748 | */ | |
7749 | void hugetlb_unshare_all_pmds(struct vm_area_struct *vma) | |
7750 | { | |
7751 | hugetlb_unshare_pmds(vma, ALIGN(vma->vm_start, PUD_SIZE), | |
7752 | ALIGN_DOWN(vma->vm_end, PUD_SIZE)); | |
7753 | } | |
7754 | ||
cf11e85f | 7755 | #ifdef CONFIG_CMA |
cf11e85f RG |
7756 | static bool cma_reserve_called __initdata; |
7757 | ||
7758 | static int __init cmdline_parse_hugetlb_cma(char *p) | |
7759 | { | |
38e719ab BW |
7760 | int nid, count = 0; |
7761 | unsigned long tmp; | |
7762 | char *s = p; | |
7763 | ||
7764 | while (*s) { | |
7765 | if (sscanf(s, "%lu%n", &tmp, &count) != 1) | |
7766 | break; | |
7767 | ||
7768 | if (s[count] == ':') { | |
f9317f77 | 7769 | if (tmp >= MAX_NUMNODES) |
38e719ab | 7770 | break; |
f9317f77 | 7771 | nid = array_index_nospec(tmp, MAX_NUMNODES); |
38e719ab BW |
7772 | |
7773 | s += count + 1; | |
7774 | tmp = memparse(s, &s); | |
7775 | hugetlb_cma_size_in_node[nid] = tmp; | |
7776 | hugetlb_cma_size += tmp; | |
7777 | ||
7778 | /* | |
7779 | * Skip the separator if have one, otherwise | |
7780 | * break the parsing. | |
7781 | */ | |
7782 | if (*s == ',') | |
7783 | s++; | |
7784 | else | |
7785 | break; | |
7786 | } else { | |
7787 | hugetlb_cma_size = memparse(p, &p); | |
7788 | break; | |
7789 | } | |
7790 | } | |
7791 | ||
cf11e85f RG |
7792 | return 0; |
7793 | } | |
7794 | ||
7795 | early_param("hugetlb_cma", cmdline_parse_hugetlb_cma); | |
7796 | ||
7797 | void __init hugetlb_cma_reserve(int order) | |
7798 | { | |
7799 | unsigned long size, reserved, per_node; | |
38e719ab | 7800 | bool node_specific_cma_alloc = false; |
cf11e85f RG |
7801 | int nid; |
7802 | ||
ce70cfb1 AK |
7803 | /* |
7804 | * HugeTLB CMA reservation is required for gigantic | |
7805 | * huge pages which could not be allocated via the | |
7806 | * page allocator. Just warn if there is any change | |
7807 | * breaking this assumption. | |
7808 | */ | |
7809 | VM_WARN_ON(order <= MAX_PAGE_ORDER); | |
cf11e85f RG |
7810 | cma_reserve_called = true; |
7811 | ||
38e719ab BW |
7812 | if (!hugetlb_cma_size) |
7813 | return; | |
7814 | ||
7815 | for (nid = 0; nid < MAX_NUMNODES; nid++) { | |
7816 | if (hugetlb_cma_size_in_node[nid] == 0) | |
7817 | continue; | |
7818 | ||
30a51400 | 7819 | if (!node_online(nid)) { |
38e719ab BW |
7820 | pr_warn("hugetlb_cma: invalid node %d specified\n", nid); |
7821 | hugetlb_cma_size -= hugetlb_cma_size_in_node[nid]; | |
7822 | hugetlb_cma_size_in_node[nid] = 0; | |
7823 | continue; | |
7824 | } | |
7825 | ||
7826 | if (hugetlb_cma_size_in_node[nid] < (PAGE_SIZE << order)) { | |
7827 | pr_warn("hugetlb_cma: cma area of node %d should be at least %lu MiB\n", | |
7828 | nid, (PAGE_SIZE << order) / SZ_1M); | |
7829 | hugetlb_cma_size -= hugetlb_cma_size_in_node[nid]; | |
7830 | hugetlb_cma_size_in_node[nid] = 0; | |
7831 | } else { | |
7832 | node_specific_cma_alloc = true; | |
7833 | } | |
7834 | } | |
7835 | ||
7836 | /* Validate the CMA size again in case some invalid nodes specified. */ | |
cf11e85f RG |
7837 | if (!hugetlb_cma_size) |
7838 | return; | |
7839 | ||
7840 | if (hugetlb_cma_size < (PAGE_SIZE << order)) { | |
7841 | pr_warn("hugetlb_cma: cma area should be at least %lu MiB\n", | |
7842 | (PAGE_SIZE << order) / SZ_1M); | |
a01f4390 | 7843 | hugetlb_cma_size = 0; |
cf11e85f RG |
7844 | return; |
7845 | } | |
7846 | ||
38e719ab BW |
7847 | if (!node_specific_cma_alloc) { |
7848 | /* | |
7849 | * If 3 GB area is requested on a machine with 4 numa nodes, | |
7850 | * let's allocate 1 GB on first three nodes and ignore the last one. | |
7851 | */ | |
7852 | per_node = DIV_ROUND_UP(hugetlb_cma_size, nr_online_nodes); | |
7853 | pr_info("hugetlb_cma: reserve %lu MiB, up to %lu MiB per node\n", | |
7854 | hugetlb_cma_size / SZ_1M, per_node / SZ_1M); | |
7855 | } | |
cf11e85f RG |
7856 | |
7857 | reserved = 0; | |
30a51400 | 7858 | for_each_online_node(nid) { |
cf11e85f | 7859 | int res; |
2281f797 | 7860 | char name[CMA_MAX_NAME]; |
cf11e85f | 7861 | |
38e719ab BW |
7862 | if (node_specific_cma_alloc) { |
7863 | if (hugetlb_cma_size_in_node[nid] == 0) | |
7864 | continue; | |
7865 | ||
7866 | size = hugetlb_cma_size_in_node[nid]; | |
7867 | } else { | |
7868 | size = min(per_node, hugetlb_cma_size - reserved); | |
7869 | } | |
7870 | ||
cf11e85f RG |
7871 | size = round_up(size, PAGE_SIZE << order); |
7872 | ||
2281f797 | 7873 | snprintf(name, sizeof(name), "hugetlb%d", nid); |
a01f4390 MK |
7874 | /* |
7875 | * Note that 'order per bit' is based on smallest size that | |
7876 | * may be returned to CMA allocator in the case of | |
7877 | * huge page demotion. | |
7878 | */ | |
7879 | res = cma_declare_contiguous_nid(0, size, 0, | |
7880 | PAGE_SIZE << HUGETLB_PAGE_ORDER, | |
29d0f41d | 7881 | 0, false, name, |
cf11e85f RG |
7882 | &hugetlb_cma[nid], nid); |
7883 | if (res) { | |
7884 | pr_warn("hugetlb_cma: reservation failed: err %d, node %d", | |
7885 | res, nid); | |
7886 | continue; | |
7887 | } | |
7888 | ||
7889 | reserved += size; | |
7890 | pr_info("hugetlb_cma: reserved %lu MiB on node %d\n", | |
7891 | size / SZ_1M, nid); | |
7892 | ||
7893 | if (reserved >= hugetlb_cma_size) | |
7894 | break; | |
7895 | } | |
a01f4390 MK |
7896 | |
7897 | if (!reserved) | |
7898 | /* | |
7899 | * hugetlb_cma_size is used to determine if allocations from | |
7900 | * cma are possible. Set to zero if no cma regions are set up. | |
7901 | */ | |
7902 | hugetlb_cma_size = 0; | |
cf11e85f RG |
7903 | } |
7904 | ||
263b8998 | 7905 | static void __init hugetlb_cma_check(void) |
cf11e85f RG |
7906 | { |
7907 | if (!hugetlb_cma_size || cma_reserve_called) | |
7908 | return; | |
7909 | ||
7910 | pr_warn("hugetlb_cma: the option isn't supported by current arch\n"); | |
7911 | } | |
7912 | ||
7913 | #endif /* CONFIG_CMA */ |