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> |
d6606683 | 38 | |
63551ae0 | 39 | #include <asm/page.h> |
ca15ca40 | 40 | #include <asm/pgalloc.h> |
24669e58 | 41 | #include <asm/tlb.h> |
63551ae0 | 42 | |
24669e58 | 43 | #include <linux/io.h> |
63551ae0 | 44 | #include <linux/hugetlb.h> |
9dd540e2 | 45 | #include <linux/hugetlb_cgroup.h> |
9a305230 | 46 | #include <linux/node.h> |
ab5ac90a | 47 | #include <linux/page_owner.h> |
7835e98b | 48 | #include "internal.h" |
f41f2ed4 | 49 | #include "hugetlb_vmemmap.h" |
1da177e4 | 50 | |
c3f38a38 | 51 | int hugetlb_max_hstate __read_mostly; |
e5ff2159 AK |
52 | unsigned int default_hstate_idx; |
53 | struct hstate hstates[HUGE_MAX_HSTATE]; | |
cf11e85f | 54 | |
dbda8fea | 55 | #ifdef CONFIG_CMA |
cf11e85f | 56 | static struct cma *hugetlb_cma[MAX_NUMNODES]; |
38e719ab | 57 | static unsigned long hugetlb_cma_size_in_node[MAX_NUMNODES] __initdata; |
2f6c57d6 | 58 | static bool hugetlb_cma_folio(struct folio *folio, unsigned int order) |
a01f4390 | 59 | { |
2f6c57d6 | 60 | return cma_pages_valid(hugetlb_cma[folio_nid(folio)], &folio->page, |
a01f4390 MK |
61 | 1 << order); |
62 | } | |
63 | #else | |
2f6c57d6 | 64 | static bool hugetlb_cma_folio(struct folio *folio, unsigned int order) |
a01f4390 MK |
65 | { |
66 | return false; | |
67 | } | |
dbda8fea BS |
68 | #endif |
69 | static unsigned long hugetlb_cma_size __initdata; | |
cf11e85f | 70 | |
53ba51d2 JT |
71 | __initdata LIST_HEAD(huge_boot_pages); |
72 | ||
e5ff2159 AK |
73 | /* for command line parsing */ |
74 | static struct hstate * __initdata parsed_hstate; | |
75 | static unsigned long __initdata default_hstate_max_huge_pages; | |
9fee021d | 76 | static bool __initdata parsed_valid_hugepagesz = true; |
282f4214 | 77 | static bool __initdata parsed_default_hugepagesz; |
b5389086 | 78 | static unsigned int default_hugepages_in_node[MAX_NUMNODES] __initdata; |
e5ff2159 | 79 | |
3935baa9 | 80 | /* |
31caf665 NH |
81 | * Protects updates to hugepage_freelists, hugepage_activelist, nr_huge_pages, |
82 | * free_huge_pages, and surplus_huge_pages. | |
3935baa9 | 83 | */ |
c3f38a38 | 84 | DEFINE_SPINLOCK(hugetlb_lock); |
0bd0f9fb | 85 | |
8382d914 DB |
86 | /* |
87 | * Serializes faults on the same logical page. This is used to | |
88 | * prevent spurious OOMs when the hugepage pool is fully utilized. | |
89 | */ | |
90 | static int num_fault_mutexes; | |
c672c7f2 | 91 | struct mutex *hugetlb_fault_mutex_table ____cacheline_aligned_in_smp; |
8382d914 | 92 | |
7ca02d0a MK |
93 | /* Forward declaration */ |
94 | static int hugetlb_acct_memory(struct hstate *h, long delta); | |
8d9bfb26 MK |
95 | static void hugetlb_vma_lock_free(struct vm_area_struct *vma); |
96 | static void hugetlb_vma_lock_alloc(struct vm_area_struct *vma); | |
ecfbd733 | 97 | static void __hugetlb_vma_unlock_write_free(struct vm_area_struct *vma); |
b30c14cd JH |
98 | static void hugetlb_unshare_pmds(struct vm_area_struct *vma, |
99 | unsigned long start, unsigned long end); | |
bf491692 | 100 | static struct resv_map *vma_resv_map(struct vm_area_struct *vma); |
7ca02d0a | 101 | |
1d88433b | 102 | static inline bool subpool_is_free(struct hugepage_subpool *spool) |
90481622 | 103 | { |
1d88433b ML |
104 | if (spool->count) |
105 | return false; | |
106 | if (spool->max_hpages != -1) | |
107 | return spool->used_hpages == 0; | |
108 | if (spool->min_hpages != -1) | |
109 | return spool->rsv_hpages == spool->min_hpages; | |
110 | ||
111 | return true; | |
112 | } | |
90481622 | 113 | |
db71ef79 MK |
114 | static inline void unlock_or_release_subpool(struct hugepage_subpool *spool, |
115 | unsigned long irq_flags) | |
1d88433b | 116 | { |
db71ef79 | 117 | spin_unlock_irqrestore(&spool->lock, irq_flags); |
90481622 DG |
118 | |
119 | /* If no pages are used, and no other handles to the subpool | |
7c8de358 | 120 | * remain, give up any reservations based on minimum size and |
7ca02d0a | 121 | * free the subpool */ |
1d88433b | 122 | if (subpool_is_free(spool)) { |
7ca02d0a MK |
123 | if (spool->min_hpages != -1) |
124 | hugetlb_acct_memory(spool->hstate, | |
125 | -spool->min_hpages); | |
90481622 | 126 | kfree(spool); |
7ca02d0a | 127 | } |
90481622 DG |
128 | } |
129 | ||
7ca02d0a MK |
130 | struct hugepage_subpool *hugepage_new_subpool(struct hstate *h, long max_hpages, |
131 | long min_hpages) | |
90481622 DG |
132 | { |
133 | struct hugepage_subpool *spool; | |
134 | ||
c6a91820 | 135 | spool = kzalloc(sizeof(*spool), GFP_KERNEL); |
90481622 DG |
136 | if (!spool) |
137 | return NULL; | |
138 | ||
139 | spin_lock_init(&spool->lock); | |
140 | spool->count = 1; | |
7ca02d0a MK |
141 | spool->max_hpages = max_hpages; |
142 | spool->hstate = h; | |
143 | spool->min_hpages = min_hpages; | |
144 | ||
145 | if (min_hpages != -1 && hugetlb_acct_memory(h, min_hpages)) { | |
146 | kfree(spool); | |
147 | return NULL; | |
148 | } | |
149 | spool->rsv_hpages = min_hpages; | |
90481622 DG |
150 | |
151 | return spool; | |
152 | } | |
153 | ||
154 | void hugepage_put_subpool(struct hugepage_subpool *spool) | |
155 | { | |
db71ef79 MK |
156 | unsigned long flags; |
157 | ||
158 | spin_lock_irqsave(&spool->lock, flags); | |
90481622 DG |
159 | BUG_ON(!spool->count); |
160 | spool->count--; | |
db71ef79 | 161 | unlock_or_release_subpool(spool, flags); |
90481622 DG |
162 | } |
163 | ||
1c5ecae3 MK |
164 | /* |
165 | * Subpool accounting for allocating and reserving pages. | |
166 | * Return -ENOMEM if there are not enough resources to satisfy the | |
9e7ee400 | 167 | * request. Otherwise, return the number of pages by which the |
1c5ecae3 MK |
168 | * global pools must be adjusted (upward). The returned value may |
169 | * only be different than the passed value (delta) in the case where | |
7c8de358 | 170 | * a subpool minimum size must be maintained. |
1c5ecae3 MK |
171 | */ |
172 | static long hugepage_subpool_get_pages(struct hugepage_subpool *spool, | |
90481622 DG |
173 | long delta) |
174 | { | |
1c5ecae3 | 175 | long ret = delta; |
90481622 DG |
176 | |
177 | if (!spool) | |
1c5ecae3 | 178 | return ret; |
90481622 | 179 | |
db71ef79 | 180 | spin_lock_irq(&spool->lock); |
1c5ecae3 MK |
181 | |
182 | if (spool->max_hpages != -1) { /* maximum size accounting */ | |
183 | if ((spool->used_hpages + delta) <= spool->max_hpages) | |
184 | spool->used_hpages += delta; | |
185 | else { | |
186 | ret = -ENOMEM; | |
187 | goto unlock_ret; | |
188 | } | |
90481622 | 189 | } |
90481622 | 190 | |
09a95e29 MK |
191 | /* minimum size accounting */ |
192 | if (spool->min_hpages != -1 && spool->rsv_hpages) { | |
1c5ecae3 MK |
193 | if (delta > spool->rsv_hpages) { |
194 | /* | |
195 | * Asking for more reserves than those already taken on | |
196 | * behalf of subpool. Return difference. | |
197 | */ | |
198 | ret = delta - spool->rsv_hpages; | |
199 | spool->rsv_hpages = 0; | |
200 | } else { | |
201 | ret = 0; /* reserves already accounted for */ | |
202 | spool->rsv_hpages -= delta; | |
203 | } | |
204 | } | |
205 | ||
206 | unlock_ret: | |
db71ef79 | 207 | spin_unlock_irq(&spool->lock); |
90481622 DG |
208 | return ret; |
209 | } | |
210 | ||
1c5ecae3 MK |
211 | /* |
212 | * Subpool accounting for freeing and unreserving pages. | |
213 | * Return the number of global page reservations that must be dropped. | |
214 | * The return value may only be different than the passed value (delta) | |
215 | * in the case where a subpool minimum size must be maintained. | |
216 | */ | |
217 | static long hugepage_subpool_put_pages(struct hugepage_subpool *spool, | |
90481622 DG |
218 | long delta) |
219 | { | |
1c5ecae3 | 220 | long ret = delta; |
db71ef79 | 221 | unsigned long flags; |
1c5ecae3 | 222 | |
90481622 | 223 | if (!spool) |
1c5ecae3 | 224 | return delta; |
90481622 | 225 | |
db71ef79 | 226 | spin_lock_irqsave(&spool->lock, flags); |
1c5ecae3 MK |
227 | |
228 | if (spool->max_hpages != -1) /* maximum size accounting */ | |
229 | spool->used_hpages -= delta; | |
230 | ||
09a95e29 MK |
231 | /* minimum size accounting */ |
232 | if (spool->min_hpages != -1 && spool->used_hpages < spool->min_hpages) { | |
1c5ecae3 MK |
233 | if (spool->rsv_hpages + delta <= spool->min_hpages) |
234 | ret = 0; | |
235 | else | |
236 | ret = spool->rsv_hpages + delta - spool->min_hpages; | |
237 | ||
238 | spool->rsv_hpages += delta; | |
239 | if (spool->rsv_hpages > spool->min_hpages) | |
240 | spool->rsv_hpages = spool->min_hpages; | |
241 | } | |
242 | ||
243 | /* | |
244 | * If hugetlbfs_put_super couldn't free spool due to an outstanding | |
245 | * quota reference, free it now. | |
246 | */ | |
db71ef79 | 247 | unlock_or_release_subpool(spool, flags); |
1c5ecae3 MK |
248 | |
249 | return ret; | |
90481622 DG |
250 | } |
251 | ||
252 | static inline struct hugepage_subpool *subpool_inode(struct inode *inode) | |
253 | { | |
254 | return HUGETLBFS_SB(inode->i_sb)->spool; | |
255 | } | |
256 | ||
257 | static inline struct hugepage_subpool *subpool_vma(struct vm_area_struct *vma) | |
258 | { | |
496ad9aa | 259 | return subpool_inode(file_inode(vma->vm_file)); |
90481622 DG |
260 | } |
261 | ||
e700898f MK |
262 | /* |
263 | * hugetlb vma_lock helper routines | |
264 | */ | |
e700898f MK |
265 | void hugetlb_vma_lock_read(struct vm_area_struct *vma) |
266 | { | |
267 | if (__vma_shareable_lock(vma)) { | |
268 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
269 | ||
270 | down_read(&vma_lock->rw_sema); | |
bf491692 RR |
271 | } else if (__vma_private_lock(vma)) { |
272 | struct resv_map *resv_map = vma_resv_map(vma); | |
273 | ||
274 | down_read(&resv_map->rw_sema); | |
e700898f MK |
275 | } |
276 | } | |
277 | ||
278 | void hugetlb_vma_unlock_read(struct vm_area_struct *vma) | |
279 | { | |
280 | if (__vma_shareable_lock(vma)) { | |
281 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
282 | ||
283 | up_read(&vma_lock->rw_sema); | |
bf491692 RR |
284 | } else if (__vma_private_lock(vma)) { |
285 | struct resv_map *resv_map = vma_resv_map(vma); | |
286 | ||
287 | up_read(&resv_map->rw_sema); | |
e700898f MK |
288 | } |
289 | } | |
290 | ||
291 | void hugetlb_vma_lock_write(struct vm_area_struct *vma) | |
292 | { | |
293 | if (__vma_shareable_lock(vma)) { | |
294 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
295 | ||
296 | down_write(&vma_lock->rw_sema); | |
bf491692 RR |
297 | } else if (__vma_private_lock(vma)) { |
298 | struct resv_map *resv_map = vma_resv_map(vma); | |
299 | ||
300 | down_write(&resv_map->rw_sema); | |
e700898f MK |
301 | } |
302 | } | |
303 | ||
304 | void hugetlb_vma_unlock_write(struct vm_area_struct *vma) | |
305 | { | |
306 | if (__vma_shareable_lock(vma)) { | |
307 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
308 | ||
309 | up_write(&vma_lock->rw_sema); | |
bf491692 RR |
310 | } else if (__vma_private_lock(vma)) { |
311 | struct resv_map *resv_map = vma_resv_map(vma); | |
312 | ||
313 | up_write(&resv_map->rw_sema); | |
e700898f MK |
314 | } |
315 | } | |
316 | ||
317 | int hugetlb_vma_trylock_write(struct vm_area_struct *vma) | |
318 | { | |
e700898f | 319 | |
bf491692 RR |
320 | if (__vma_shareable_lock(vma)) { |
321 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
e700898f | 322 | |
bf491692 RR |
323 | return down_write_trylock(&vma_lock->rw_sema); |
324 | } else if (__vma_private_lock(vma)) { | |
325 | struct resv_map *resv_map = vma_resv_map(vma); | |
326 | ||
327 | return down_write_trylock(&resv_map->rw_sema); | |
328 | } | |
329 | ||
330 | return 1; | |
e700898f MK |
331 | } |
332 | ||
333 | void hugetlb_vma_assert_locked(struct vm_area_struct *vma) | |
334 | { | |
335 | if (__vma_shareable_lock(vma)) { | |
336 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
337 | ||
338 | lockdep_assert_held(&vma_lock->rw_sema); | |
bf491692 RR |
339 | } else if (__vma_private_lock(vma)) { |
340 | struct resv_map *resv_map = vma_resv_map(vma); | |
341 | ||
342 | lockdep_assert_held(&resv_map->rw_sema); | |
e700898f MK |
343 | } |
344 | } | |
345 | ||
346 | void hugetlb_vma_lock_release(struct kref *kref) | |
347 | { | |
348 | struct hugetlb_vma_lock *vma_lock = container_of(kref, | |
349 | struct hugetlb_vma_lock, refs); | |
350 | ||
351 | kfree(vma_lock); | |
352 | } | |
353 | ||
354 | static void __hugetlb_vma_unlock_write_put(struct hugetlb_vma_lock *vma_lock) | |
355 | { | |
356 | struct vm_area_struct *vma = vma_lock->vma; | |
357 | ||
358 | /* | |
359 | * vma_lock structure may or not be released as a result of put, | |
360 | * it certainly will no longer be attached to vma so clear pointer. | |
361 | * Semaphore synchronizes access to vma_lock->vma field. | |
362 | */ | |
363 | vma_lock->vma = NULL; | |
364 | vma->vm_private_data = NULL; | |
365 | up_write(&vma_lock->rw_sema); | |
366 | kref_put(&vma_lock->refs, hugetlb_vma_lock_release); | |
367 | } | |
368 | ||
369 | static void __hugetlb_vma_unlock_write_free(struct vm_area_struct *vma) | |
370 | { | |
371 | if (__vma_shareable_lock(vma)) { | |
372 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
373 | ||
374 | __hugetlb_vma_unlock_write_put(vma_lock); | |
bf491692 RR |
375 | } else if (__vma_private_lock(vma)) { |
376 | struct resv_map *resv_map = vma_resv_map(vma); | |
377 | ||
378 | /* no free for anon vmas, but still need to unlock */ | |
379 | up_write(&resv_map->rw_sema); | |
e700898f MK |
380 | } |
381 | } | |
382 | ||
383 | static void hugetlb_vma_lock_free(struct vm_area_struct *vma) | |
384 | { | |
385 | /* | |
386 | * Only present in sharable vmas. | |
387 | */ | |
388 | if (!vma || !__vma_shareable_lock(vma)) | |
389 | return; | |
390 | ||
391 | if (vma->vm_private_data) { | |
392 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
393 | ||
394 | down_write(&vma_lock->rw_sema); | |
395 | __hugetlb_vma_unlock_write_put(vma_lock); | |
396 | } | |
397 | } | |
398 | ||
399 | static void hugetlb_vma_lock_alloc(struct vm_area_struct *vma) | |
400 | { | |
401 | struct hugetlb_vma_lock *vma_lock; | |
402 | ||
403 | /* Only establish in (flags) sharable vmas */ | |
404 | if (!vma || !(vma->vm_flags & VM_MAYSHARE)) | |
405 | return; | |
406 | ||
407 | /* Should never get here with non-NULL vm_private_data */ | |
408 | if (vma->vm_private_data) | |
409 | return; | |
410 | ||
411 | vma_lock = kmalloc(sizeof(*vma_lock), GFP_KERNEL); | |
412 | if (!vma_lock) { | |
413 | /* | |
414 | * If we can not allocate structure, then vma can not | |
415 | * participate in pmd sharing. This is only a possible | |
416 | * performance enhancement and memory saving issue. | |
417 | * However, the lock is also used to synchronize page | |
418 | * faults with truncation. If the lock is not present, | |
419 | * unlikely races could leave pages in a file past i_size | |
420 | * until the file is removed. Warn in the unlikely case of | |
421 | * allocation failure. | |
422 | */ | |
423 | pr_warn_once("HugeTLB: unable to allocate vma specific lock\n"); | |
424 | return; | |
425 | } | |
426 | ||
427 | kref_init(&vma_lock->refs); | |
428 | init_rwsem(&vma_lock->rw_sema); | |
429 | vma_lock->vma = vma; | |
430 | vma->vm_private_data = vma_lock; | |
431 | } | |
432 | ||
0db9d74e MA |
433 | /* Helper that removes a struct file_region from the resv_map cache and returns |
434 | * it for use. | |
435 | */ | |
436 | static struct file_region * | |
437 | get_file_region_entry_from_cache(struct resv_map *resv, long from, long to) | |
438 | { | |
3259914f | 439 | struct file_region *nrg; |
0db9d74e MA |
440 | |
441 | VM_BUG_ON(resv->region_cache_count <= 0); | |
442 | ||
443 | resv->region_cache_count--; | |
444 | nrg = list_first_entry(&resv->region_cache, struct file_region, link); | |
0db9d74e MA |
445 | list_del(&nrg->link); |
446 | ||
447 | nrg->from = from; | |
448 | nrg->to = to; | |
449 | ||
450 | return nrg; | |
451 | } | |
452 | ||
075a61d0 MA |
453 | static void copy_hugetlb_cgroup_uncharge_info(struct file_region *nrg, |
454 | struct file_region *rg) | |
455 | { | |
456 | #ifdef CONFIG_CGROUP_HUGETLB | |
457 | nrg->reservation_counter = rg->reservation_counter; | |
458 | nrg->css = rg->css; | |
459 | if (rg->css) | |
460 | css_get(rg->css); | |
461 | #endif | |
462 | } | |
463 | ||
464 | /* Helper that records hugetlb_cgroup uncharge info. */ | |
465 | static void record_hugetlb_cgroup_uncharge_info(struct hugetlb_cgroup *h_cg, | |
466 | struct hstate *h, | |
467 | struct resv_map *resv, | |
468 | struct file_region *nrg) | |
469 | { | |
470 | #ifdef CONFIG_CGROUP_HUGETLB | |
471 | if (h_cg) { | |
472 | nrg->reservation_counter = | |
473 | &h_cg->rsvd_hugepage[hstate_index(h)]; | |
474 | nrg->css = &h_cg->css; | |
d85aecf2 ML |
475 | /* |
476 | * The caller will hold exactly one h_cg->css reference for the | |
477 | * whole contiguous reservation region. But this area might be | |
478 | * scattered when there are already some file_regions reside in | |
479 | * it. As a result, many file_regions may share only one css | |
480 | * reference. In order to ensure that one file_region must hold | |
481 | * exactly one h_cg->css reference, we should do css_get for | |
482 | * each file_region and leave the reference held by caller | |
483 | * untouched. | |
484 | */ | |
485 | css_get(&h_cg->css); | |
075a61d0 MA |
486 | if (!resv->pages_per_hpage) |
487 | resv->pages_per_hpage = pages_per_huge_page(h); | |
488 | /* pages_per_hpage should be the same for all entries in | |
489 | * a resv_map. | |
490 | */ | |
491 | VM_BUG_ON(resv->pages_per_hpage != pages_per_huge_page(h)); | |
492 | } else { | |
493 | nrg->reservation_counter = NULL; | |
494 | nrg->css = NULL; | |
495 | } | |
496 | #endif | |
497 | } | |
498 | ||
d85aecf2 ML |
499 | static void put_uncharge_info(struct file_region *rg) |
500 | { | |
501 | #ifdef CONFIG_CGROUP_HUGETLB | |
502 | if (rg->css) | |
503 | css_put(rg->css); | |
504 | #endif | |
505 | } | |
506 | ||
a9b3f867 MA |
507 | static bool has_same_uncharge_info(struct file_region *rg, |
508 | struct file_region *org) | |
509 | { | |
510 | #ifdef CONFIG_CGROUP_HUGETLB | |
0739eb43 | 511 | return rg->reservation_counter == org->reservation_counter && |
a9b3f867 MA |
512 | rg->css == org->css; |
513 | ||
514 | #else | |
515 | return true; | |
516 | #endif | |
517 | } | |
518 | ||
519 | static void coalesce_file_region(struct resv_map *resv, struct file_region *rg) | |
520 | { | |
3259914f | 521 | struct file_region *nrg, *prg; |
a9b3f867 MA |
522 | |
523 | prg = list_prev_entry(rg, link); | |
524 | if (&prg->link != &resv->regions && prg->to == rg->from && | |
525 | has_same_uncharge_info(prg, rg)) { | |
526 | prg->to = rg->to; | |
527 | ||
528 | list_del(&rg->link); | |
d85aecf2 | 529 | put_uncharge_info(rg); |
a9b3f867 MA |
530 | kfree(rg); |
531 | ||
7db5e7b6 | 532 | rg = prg; |
a9b3f867 MA |
533 | } |
534 | ||
535 | nrg = list_next_entry(rg, link); | |
536 | if (&nrg->link != &resv->regions && nrg->from == rg->to && | |
537 | has_same_uncharge_info(nrg, rg)) { | |
538 | nrg->from = rg->from; | |
539 | ||
540 | list_del(&rg->link); | |
d85aecf2 | 541 | put_uncharge_info(rg); |
a9b3f867 | 542 | kfree(rg); |
a9b3f867 MA |
543 | } |
544 | } | |
545 | ||
2103cf9c | 546 | static inline long |
84448c8e | 547 | hugetlb_resv_map_add(struct resv_map *map, struct list_head *rg, long from, |
2103cf9c PX |
548 | long to, struct hstate *h, struct hugetlb_cgroup *cg, |
549 | long *regions_needed) | |
550 | { | |
551 | struct file_region *nrg; | |
552 | ||
553 | if (!regions_needed) { | |
554 | nrg = get_file_region_entry_from_cache(map, from, to); | |
555 | record_hugetlb_cgroup_uncharge_info(cg, h, map, nrg); | |
84448c8e | 556 | list_add(&nrg->link, rg); |
2103cf9c PX |
557 | coalesce_file_region(map, nrg); |
558 | } else | |
559 | *regions_needed += 1; | |
560 | ||
561 | return to - from; | |
562 | } | |
563 | ||
972a3da3 WY |
564 | /* |
565 | * Must be called with resv->lock held. | |
566 | * | |
567 | * Calling this with regions_needed != NULL will count the number of pages | |
568 | * to be added but will not modify the linked list. And regions_needed will | |
569 | * indicate the number of file_regions needed in the cache to carry out to add | |
570 | * the regions for this range. | |
d75c6af9 MA |
571 | */ |
572 | static long add_reservation_in_range(struct resv_map *resv, long f, long t, | |
075a61d0 | 573 | struct hugetlb_cgroup *h_cg, |
972a3da3 | 574 | struct hstate *h, long *regions_needed) |
d75c6af9 | 575 | { |
0db9d74e | 576 | long add = 0; |
d75c6af9 | 577 | struct list_head *head = &resv->regions; |
0db9d74e | 578 | long last_accounted_offset = f; |
84448c8e JK |
579 | struct file_region *iter, *trg = NULL; |
580 | struct list_head *rg = NULL; | |
d75c6af9 | 581 | |
0db9d74e MA |
582 | if (regions_needed) |
583 | *regions_needed = 0; | |
d75c6af9 | 584 | |
0db9d74e | 585 | /* In this loop, we essentially handle an entry for the range |
84448c8e | 586 | * [last_accounted_offset, iter->from), at every iteration, with some |
0db9d74e MA |
587 | * bounds checking. |
588 | */ | |
84448c8e | 589 | list_for_each_entry_safe(iter, trg, head, link) { |
0db9d74e | 590 | /* Skip irrelevant regions that start before our range. */ |
84448c8e | 591 | if (iter->from < f) { |
0db9d74e MA |
592 | /* If this region ends after the last accounted offset, |
593 | * then we need to update last_accounted_offset. | |
594 | */ | |
84448c8e JK |
595 | if (iter->to > last_accounted_offset) |
596 | last_accounted_offset = iter->to; | |
0db9d74e MA |
597 | continue; |
598 | } | |
d75c6af9 | 599 | |
0db9d74e MA |
600 | /* When we find a region that starts beyond our range, we've |
601 | * finished. | |
602 | */ | |
84448c8e JK |
603 | if (iter->from >= t) { |
604 | rg = iter->link.prev; | |
d75c6af9 | 605 | break; |
84448c8e | 606 | } |
d75c6af9 | 607 | |
84448c8e | 608 | /* Add an entry for last_accounted_offset -> iter->from, and |
0db9d74e MA |
609 | * update last_accounted_offset. |
610 | */ | |
84448c8e JK |
611 | if (iter->from > last_accounted_offset) |
612 | add += hugetlb_resv_map_add(resv, iter->link.prev, | |
2103cf9c | 613 | last_accounted_offset, |
84448c8e | 614 | iter->from, h, h_cg, |
2103cf9c | 615 | regions_needed); |
0db9d74e | 616 | |
84448c8e | 617 | last_accounted_offset = iter->to; |
0db9d74e MA |
618 | } |
619 | ||
620 | /* Handle the case where our range extends beyond | |
621 | * last_accounted_offset. | |
622 | */ | |
84448c8e JK |
623 | if (!rg) |
624 | rg = head->prev; | |
2103cf9c PX |
625 | if (last_accounted_offset < t) |
626 | add += hugetlb_resv_map_add(resv, rg, last_accounted_offset, | |
627 | t, h, h_cg, regions_needed); | |
0db9d74e | 628 | |
0db9d74e MA |
629 | return add; |
630 | } | |
631 | ||
632 | /* Must be called with resv->lock acquired. Will drop lock to allocate entries. | |
633 | */ | |
634 | static int allocate_file_region_entries(struct resv_map *resv, | |
635 | int regions_needed) | |
636 | __must_hold(&resv->lock) | |
637 | { | |
34665341 | 638 | LIST_HEAD(allocated_regions); |
0db9d74e MA |
639 | int to_allocate = 0, i = 0; |
640 | struct file_region *trg = NULL, *rg = NULL; | |
641 | ||
642 | VM_BUG_ON(regions_needed < 0); | |
643 | ||
0db9d74e MA |
644 | /* |
645 | * Check for sufficient descriptors in the cache to accommodate | |
646 | * the number of in progress add operations plus regions_needed. | |
647 | * | |
648 | * This is a while loop because when we drop the lock, some other call | |
649 | * to region_add or region_del may have consumed some region_entries, | |
650 | * so we keep looping here until we finally have enough entries for | |
651 | * (adds_in_progress + regions_needed). | |
652 | */ | |
653 | while (resv->region_cache_count < | |
654 | (resv->adds_in_progress + regions_needed)) { | |
655 | to_allocate = resv->adds_in_progress + regions_needed - | |
656 | resv->region_cache_count; | |
657 | ||
658 | /* At this point, we should have enough entries in the cache | |
f0953a1b | 659 | * for all the existing adds_in_progress. We should only be |
0db9d74e | 660 | * needing to allocate for regions_needed. |
d75c6af9 | 661 | */ |
0db9d74e MA |
662 | VM_BUG_ON(resv->region_cache_count < resv->adds_in_progress); |
663 | ||
664 | spin_unlock(&resv->lock); | |
665 | for (i = 0; i < to_allocate; i++) { | |
666 | trg = kmalloc(sizeof(*trg), GFP_KERNEL); | |
667 | if (!trg) | |
668 | goto out_of_memory; | |
669 | list_add(&trg->link, &allocated_regions); | |
d75c6af9 | 670 | } |
d75c6af9 | 671 | |
0db9d74e MA |
672 | spin_lock(&resv->lock); |
673 | ||
d3ec7b6e WY |
674 | list_splice(&allocated_regions, &resv->region_cache); |
675 | resv->region_cache_count += to_allocate; | |
d75c6af9 MA |
676 | } |
677 | ||
0db9d74e | 678 | return 0; |
d75c6af9 | 679 | |
0db9d74e MA |
680 | out_of_memory: |
681 | list_for_each_entry_safe(rg, trg, &allocated_regions, link) { | |
682 | list_del(&rg->link); | |
683 | kfree(rg); | |
684 | } | |
685 | return -ENOMEM; | |
d75c6af9 MA |
686 | } |
687 | ||
1dd308a7 MK |
688 | /* |
689 | * Add the huge page range represented by [f, t) to the reserve | |
0db9d74e MA |
690 | * map. Regions will be taken from the cache to fill in this range. |
691 | * Sufficient regions should exist in the cache due to the previous | |
692 | * call to region_chg with the same range, but in some cases the cache will not | |
693 | * have sufficient entries due to races with other code doing region_add or | |
694 | * region_del. The extra needed entries will be allocated. | |
cf3ad20b | 695 | * |
0db9d74e MA |
696 | * regions_needed is the out value provided by a previous call to region_chg. |
697 | * | |
698 | * Return the number of new huge pages added to the map. This number is greater | |
699 | * than or equal to zero. If file_region entries needed to be allocated for | |
7c8de358 | 700 | * this operation and we were not able to allocate, it returns -ENOMEM. |
0db9d74e MA |
701 | * region_add of regions of length 1 never allocate file_regions and cannot |
702 | * fail; region_chg will always allocate at least 1 entry and a region_add for | |
703 | * 1 page will only require at most 1 entry. | |
1dd308a7 | 704 | */ |
0db9d74e | 705 | static long region_add(struct resv_map *resv, long f, long t, |
075a61d0 MA |
706 | long in_regions_needed, struct hstate *h, |
707 | struct hugetlb_cgroup *h_cg) | |
96822904 | 708 | { |
0db9d74e | 709 | long add = 0, actual_regions_needed = 0; |
96822904 | 710 | |
7b24d861 | 711 | spin_lock(&resv->lock); |
0db9d74e MA |
712 | retry: |
713 | ||
714 | /* Count how many regions are actually needed to execute this add. */ | |
972a3da3 WY |
715 | add_reservation_in_range(resv, f, t, NULL, NULL, |
716 | &actual_regions_needed); | |
96822904 | 717 | |
5e911373 | 718 | /* |
0db9d74e MA |
719 | * Check for sufficient descriptors in the cache to accommodate |
720 | * this add operation. Note that actual_regions_needed may be greater | |
721 | * than in_regions_needed, as the resv_map may have been modified since | |
722 | * the region_chg call. In this case, we need to make sure that we | |
723 | * allocate extra entries, such that we have enough for all the | |
724 | * existing adds_in_progress, plus the excess needed for this | |
725 | * operation. | |
5e911373 | 726 | */ |
0db9d74e MA |
727 | if (actual_regions_needed > in_regions_needed && |
728 | resv->region_cache_count < | |
729 | resv->adds_in_progress + | |
730 | (actual_regions_needed - in_regions_needed)) { | |
731 | /* region_add operation of range 1 should never need to | |
732 | * allocate file_region entries. | |
733 | */ | |
734 | VM_BUG_ON(t - f <= 1); | |
5e911373 | 735 | |
0db9d74e MA |
736 | if (allocate_file_region_entries( |
737 | resv, actual_regions_needed - in_regions_needed)) { | |
738 | return -ENOMEM; | |
739 | } | |
5e911373 | 740 | |
0db9d74e | 741 | goto retry; |
5e911373 MK |
742 | } |
743 | ||
972a3da3 | 744 | add = add_reservation_in_range(resv, f, t, h_cg, h, NULL); |
0db9d74e MA |
745 | |
746 | resv->adds_in_progress -= in_regions_needed; | |
cf3ad20b | 747 | |
7b24d861 | 748 | spin_unlock(&resv->lock); |
cf3ad20b | 749 | return add; |
96822904 AW |
750 | } |
751 | ||
1dd308a7 MK |
752 | /* |
753 | * Examine the existing reserve map and determine how many | |
754 | * huge pages in the specified range [f, t) are NOT currently | |
755 | * represented. This routine is called before a subsequent | |
756 | * call to region_add that will actually modify the reserve | |
757 | * map to add the specified range [f, t). region_chg does | |
758 | * not change the number of huge pages represented by the | |
0db9d74e MA |
759 | * map. A number of new file_region structures is added to the cache as a |
760 | * placeholder, for the subsequent region_add call to use. At least 1 | |
761 | * file_region structure is added. | |
762 | * | |
763 | * out_regions_needed is the number of regions added to the | |
764 | * resv->adds_in_progress. This value needs to be provided to a follow up call | |
765 | * to region_add or region_abort for proper accounting. | |
5e911373 MK |
766 | * |
767 | * Returns the number of huge pages that need to be added to the existing | |
768 | * reservation map for the range [f, t). This number is greater or equal to | |
769 | * zero. -ENOMEM is returned if a new file_region structure or cache entry | |
770 | * is needed and can not be allocated. | |
1dd308a7 | 771 | */ |
0db9d74e MA |
772 | static long region_chg(struct resv_map *resv, long f, long t, |
773 | long *out_regions_needed) | |
96822904 | 774 | { |
96822904 AW |
775 | long chg = 0; |
776 | ||
7b24d861 | 777 | spin_lock(&resv->lock); |
5e911373 | 778 | |
972a3da3 | 779 | /* Count how many hugepages in this range are NOT represented. */ |
075a61d0 | 780 | chg = add_reservation_in_range(resv, f, t, NULL, NULL, |
972a3da3 | 781 | out_regions_needed); |
5e911373 | 782 | |
0db9d74e MA |
783 | if (*out_regions_needed == 0) |
784 | *out_regions_needed = 1; | |
5e911373 | 785 | |
0db9d74e MA |
786 | if (allocate_file_region_entries(resv, *out_regions_needed)) |
787 | return -ENOMEM; | |
5e911373 | 788 | |
0db9d74e | 789 | resv->adds_in_progress += *out_regions_needed; |
7b24d861 | 790 | |
7b24d861 | 791 | spin_unlock(&resv->lock); |
96822904 AW |
792 | return chg; |
793 | } | |
794 | ||
5e911373 MK |
795 | /* |
796 | * Abort the in progress add operation. The adds_in_progress field | |
797 | * of the resv_map keeps track of the operations in progress between | |
798 | * calls to region_chg and region_add. Operations are sometimes | |
799 | * aborted after the call to region_chg. In such cases, region_abort | |
0db9d74e MA |
800 | * is called to decrement the adds_in_progress counter. regions_needed |
801 | * is the value returned by the region_chg call, it is used to decrement | |
802 | * the adds_in_progress counter. | |
5e911373 MK |
803 | * |
804 | * NOTE: The range arguments [f, t) are not needed or used in this | |
805 | * routine. They are kept to make reading the calling code easier as | |
806 | * arguments will match the associated region_chg call. | |
807 | */ | |
0db9d74e MA |
808 | static void region_abort(struct resv_map *resv, long f, long t, |
809 | long regions_needed) | |
5e911373 MK |
810 | { |
811 | spin_lock(&resv->lock); | |
812 | VM_BUG_ON(!resv->region_cache_count); | |
0db9d74e | 813 | resv->adds_in_progress -= regions_needed; |
5e911373 MK |
814 | spin_unlock(&resv->lock); |
815 | } | |
816 | ||
1dd308a7 | 817 | /* |
feba16e2 MK |
818 | * Delete the specified range [f, t) from the reserve map. If the |
819 | * t parameter is LONG_MAX, this indicates that ALL regions after f | |
820 | * should be deleted. Locate the regions which intersect [f, t) | |
821 | * and either trim, delete or split the existing regions. | |
822 | * | |
823 | * Returns the number of huge pages deleted from the reserve map. | |
824 | * In the normal case, the return value is zero or more. In the | |
825 | * case where a region must be split, a new region descriptor must | |
826 | * be allocated. If the allocation fails, -ENOMEM will be returned. | |
827 | * NOTE: If the parameter t == LONG_MAX, then we will never split | |
828 | * a region and possibly return -ENOMEM. Callers specifying | |
829 | * t == LONG_MAX do not need to check for -ENOMEM error. | |
1dd308a7 | 830 | */ |
feba16e2 | 831 | static long region_del(struct resv_map *resv, long f, long t) |
96822904 | 832 | { |
1406ec9b | 833 | struct list_head *head = &resv->regions; |
96822904 | 834 | struct file_region *rg, *trg; |
feba16e2 MK |
835 | struct file_region *nrg = NULL; |
836 | long del = 0; | |
96822904 | 837 | |
feba16e2 | 838 | retry: |
7b24d861 | 839 | spin_lock(&resv->lock); |
feba16e2 | 840 | list_for_each_entry_safe(rg, trg, head, link) { |
dbe409e4 MK |
841 | /* |
842 | * Skip regions before the range to be deleted. file_region | |
843 | * ranges are normally of the form [from, to). However, there | |
844 | * may be a "placeholder" entry in the map which is of the form | |
845 | * (from, to) with from == to. Check for placeholder entries | |
846 | * at the beginning of the range to be deleted. | |
847 | */ | |
848 | if (rg->to <= f && (rg->to != rg->from || rg->to != f)) | |
feba16e2 | 849 | continue; |
dbe409e4 | 850 | |
feba16e2 | 851 | if (rg->from >= t) |
96822904 | 852 | break; |
96822904 | 853 | |
feba16e2 MK |
854 | if (f > rg->from && t < rg->to) { /* Must split region */ |
855 | /* | |
856 | * Check for an entry in the cache before dropping | |
857 | * lock and attempting allocation. | |
858 | */ | |
859 | if (!nrg && | |
860 | resv->region_cache_count > resv->adds_in_progress) { | |
861 | nrg = list_first_entry(&resv->region_cache, | |
862 | struct file_region, | |
863 | link); | |
864 | list_del(&nrg->link); | |
865 | resv->region_cache_count--; | |
866 | } | |
96822904 | 867 | |
feba16e2 MK |
868 | if (!nrg) { |
869 | spin_unlock(&resv->lock); | |
870 | nrg = kmalloc(sizeof(*nrg), GFP_KERNEL); | |
871 | if (!nrg) | |
872 | return -ENOMEM; | |
873 | goto retry; | |
874 | } | |
875 | ||
876 | del += t - f; | |
79aa925b | 877 | hugetlb_cgroup_uncharge_file_region( |
d85aecf2 | 878 | resv, rg, t - f, false); |
feba16e2 MK |
879 | |
880 | /* New entry for end of split region */ | |
881 | nrg->from = t; | |
882 | nrg->to = rg->to; | |
075a61d0 MA |
883 | |
884 | copy_hugetlb_cgroup_uncharge_info(nrg, rg); | |
885 | ||
feba16e2 MK |
886 | INIT_LIST_HEAD(&nrg->link); |
887 | ||
888 | /* Original entry is trimmed */ | |
889 | rg->to = f; | |
890 | ||
891 | list_add(&nrg->link, &rg->link); | |
892 | nrg = NULL; | |
96822904 | 893 | break; |
feba16e2 MK |
894 | } |
895 | ||
896 | if (f <= rg->from && t >= rg->to) { /* Remove entire region */ | |
897 | del += rg->to - rg->from; | |
075a61d0 | 898 | hugetlb_cgroup_uncharge_file_region(resv, rg, |
d85aecf2 | 899 | rg->to - rg->from, true); |
feba16e2 MK |
900 | list_del(&rg->link); |
901 | kfree(rg); | |
902 | continue; | |
903 | } | |
904 | ||
905 | if (f <= rg->from) { /* Trim beginning of region */ | |
075a61d0 | 906 | hugetlb_cgroup_uncharge_file_region(resv, rg, |
d85aecf2 | 907 | t - rg->from, false); |
075a61d0 | 908 | |
79aa925b MK |
909 | del += t - rg->from; |
910 | rg->from = t; | |
911 | } else { /* Trim end of region */ | |
075a61d0 | 912 | hugetlb_cgroup_uncharge_file_region(resv, rg, |
d85aecf2 | 913 | rg->to - f, false); |
79aa925b MK |
914 | |
915 | del += rg->to - f; | |
916 | rg->to = f; | |
feba16e2 | 917 | } |
96822904 | 918 | } |
7b24d861 | 919 | |
7b24d861 | 920 | spin_unlock(&resv->lock); |
feba16e2 MK |
921 | kfree(nrg); |
922 | return del; | |
96822904 AW |
923 | } |
924 | ||
b5cec28d MK |
925 | /* |
926 | * A rare out of memory error was encountered which prevented removal of | |
927 | * the reserve map region for a page. The huge page itself was free'ed | |
928 | * and removed from the page cache. This routine will adjust the subpool | |
929 | * usage count, and the global reserve count if needed. By incrementing | |
930 | * these counts, the reserve map entry which could not be deleted will | |
931 | * appear as a "reserved" entry instead of simply dangling with incorrect | |
932 | * counts. | |
933 | */ | |
72e2936c | 934 | void hugetlb_fix_reserve_counts(struct inode *inode) |
b5cec28d MK |
935 | { |
936 | struct hugepage_subpool *spool = subpool_inode(inode); | |
937 | long rsv_adjust; | |
da56388c | 938 | bool reserved = false; |
b5cec28d MK |
939 | |
940 | rsv_adjust = hugepage_subpool_get_pages(spool, 1); | |
da56388c | 941 | if (rsv_adjust > 0) { |
b5cec28d MK |
942 | struct hstate *h = hstate_inode(inode); |
943 | ||
da56388c ML |
944 | if (!hugetlb_acct_memory(h, 1)) |
945 | reserved = true; | |
946 | } else if (!rsv_adjust) { | |
947 | reserved = true; | |
b5cec28d | 948 | } |
da56388c ML |
949 | |
950 | if (!reserved) | |
951 | pr_warn("hugetlb: Huge Page Reserved count may go negative.\n"); | |
b5cec28d MK |
952 | } |
953 | ||
1dd308a7 MK |
954 | /* |
955 | * Count and return the number of huge pages in the reserve map | |
956 | * that intersect with the range [f, t). | |
957 | */ | |
1406ec9b | 958 | static long region_count(struct resv_map *resv, long f, long t) |
84afd99b | 959 | { |
1406ec9b | 960 | struct list_head *head = &resv->regions; |
84afd99b AW |
961 | struct file_region *rg; |
962 | long chg = 0; | |
963 | ||
7b24d861 | 964 | spin_lock(&resv->lock); |
84afd99b AW |
965 | /* Locate each segment we overlap with, and count that overlap. */ |
966 | list_for_each_entry(rg, head, link) { | |
f2135a4a WSH |
967 | long seg_from; |
968 | long seg_to; | |
84afd99b AW |
969 | |
970 | if (rg->to <= f) | |
971 | continue; | |
972 | if (rg->from >= t) | |
973 | break; | |
974 | ||
975 | seg_from = max(rg->from, f); | |
976 | seg_to = min(rg->to, t); | |
977 | ||
978 | chg += seg_to - seg_from; | |
979 | } | |
7b24d861 | 980 | spin_unlock(&resv->lock); |
84afd99b AW |
981 | |
982 | return chg; | |
983 | } | |
984 | ||
e7c4b0bf AW |
985 | /* |
986 | * Convert the address within this vma to the page offset within | |
a08c7193 | 987 | * the mapping, huge page units here. |
e7c4b0bf | 988 | */ |
a5516438 AK |
989 | static pgoff_t vma_hugecache_offset(struct hstate *h, |
990 | struct vm_area_struct *vma, unsigned long address) | |
e7c4b0bf | 991 | { |
a5516438 AK |
992 | return ((address - vma->vm_start) >> huge_page_shift(h)) + |
993 | (vma->vm_pgoff >> huge_page_order(h)); | |
e7c4b0bf AW |
994 | } |
995 | ||
8cfd014e MWO |
996 | /** |
997 | * vma_kernel_pagesize - Page size granularity for this VMA. | |
998 | * @vma: The user mapping. | |
999 | * | |
1000 | * Folios in this VMA will be aligned to, and at least the size of the | |
1001 | * number of bytes returned by this function. | |
1002 | * | |
1003 | * Return: The default size of the folios allocated when backing a VMA. | |
08fba699 MG |
1004 | */ |
1005 | unsigned long vma_kernel_pagesize(struct vm_area_struct *vma) | |
1006 | { | |
05ea8860 DW |
1007 | if (vma->vm_ops && vma->vm_ops->pagesize) |
1008 | return vma->vm_ops->pagesize(vma); | |
1009 | return PAGE_SIZE; | |
08fba699 | 1010 | } |
f340ca0f | 1011 | EXPORT_SYMBOL_GPL(vma_kernel_pagesize); |
08fba699 | 1012 | |
3340289d MG |
1013 | /* |
1014 | * Return the page size being used by the MMU to back a VMA. In the majority | |
1015 | * of cases, the page size used by the kernel matches the MMU size. On | |
09135cc5 DW |
1016 | * architectures where it differs, an architecture-specific 'strong' |
1017 | * version of this symbol is required. | |
3340289d | 1018 | */ |
09135cc5 | 1019 | __weak unsigned long vma_mmu_pagesize(struct vm_area_struct *vma) |
3340289d MG |
1020 | { |
1021 | return vma_kernel_pagesize(vma); | |
1022 | } | |
3340289d | 1023 | |
84afd99b AW |
1024 | /* |
1025 | * Flags for MAP_PRIVATE reservations. These are stored in the bottom | |
1026 | * bits of the reservation map pointer, which are always clear due to | |
1027 | * alignment. | |
1028 | */ | |
1029 | #define HPAGE_RESV_OWNER (1UL << 0) | |
1030 | #define HPAGE_RESV_UNMAPPED (1UL << 1) | |
04f2cbe3 | 1031 | #define HPAGE_RESV_MASK (HPAGE_RESV_OWNER | HPAGE_RESV_UNMAPPED) |
84afd99b | 1032 | |
a1e78772 MG |
1033 | /* |
1034 | * These helpers are used to track how many pages are reserved for | |
1035 | * faults in a MAP_PRIVATE mapping. Only the process that called mmap() | |
1036 | * is guaranteed to have their future faults succeed. | |
1037 | * | |
8d9bfb26 | 1038 | * With the exception of hugetlb_dup_vma_private() which is called at fork(), |
a1e78772 MG |
1039 | * the reserve counters are updated with the hugetlb_lock held. It is safe |
1040 | * to reset the VMA at fork() time as it is not in use yet and there is no | |
1041 | * chance of the global counters getting corrupted as a result of the values. | |
84afd99b AW |
1042 | * |
1043 | * The private mapping reservation is represented in a subtly different | |
1044 | * manner to a shared mapping. A shared mapping has a region map associated | |
1045 | * with the underlying file, this region map represents the backing file | |
1046 | * pages which have ever had a reservation assigned which this persists even | |
1047 | * after the page is instantiated. A private mapping has a region map | |
1048 | * associated with the original mmap which is attached to all VMAs which | |
1049 | * reference it, this region map represents those offsets which have consumed | |
1050 | * reservation ie. where pages have been instantiated. | |
a1e78772 | 1051 | */ |
e7c4b0bf AW |
1052 | static unsigned long get_vma_private_data(struct vm_area_struct *vma) |
1053 | { | |
1054 | return (unsigned long)vma->vm_private_data; | |
1055 | } | |
1056 | ||
1057 | static void set_vma_private_data(struct vm_area_struct *vma, | |
1058 | unsigned long value) | |
1059 | { | |
1060 | vma->vm_private_data = (void *)value; | |
1061 | } | |
1062 | ||
e9fe92ae MA |
1063 | static void |
1064 | resv_map_set_hugetlb_cgroup_uncharge_info(struct resv_map *resv_map, | |
1065 | struct hugetlb_cgroup *h_cg, | |
1066 | struct hstate *h) | |
1067 | { | |
1068 | #ifdef CONFIG_CGROUP_HUGETLB | |
1069 | if (!h_cg || !h) { | |
1070 | resv_map->reservation_counter = NULL; | |
1071 | resv_map->pages_per_hpage = 0; | |
1072 | resv_map->css = NULL; | |
1073 | } else { | |
1074 | resv_map->reservation_counter = | |
1075 | &h_cg->rsvd_hugepage[hstate_index(h)]; | |
1076 | resv_map->pages_per_hpage = pages_per_huge_page(h); | |
1077 | resv_map->css = &h_cg->css; | |
1078 | } | |
1079 | #endif | |
1080 | } | |
1081 | ||
9119a41e | 1082 | struct resv_map *resv_map_alloc(void) |
84afd99b AW |
1083 | { |
1084 | struct resv_map *resv_map = kmalloc(sizeof(*resv_map), GFP_KERNEL); | |
5e911373 MK |
1085 | struct file_region *rg = kmalloc(sizeof(*rg), GFP_KERNEL); |
1086 | ||
1087 | if (!resv_map || !rg) { | |
1088 | kfree(resv_map); | |
1089 | kfree(rg); | |
84afd99b | 1090 | return NULL; |
5e911373 | 1091 | } |
84afd99b AW |
1092 | |
1093 | kref_init(&resv_map->refs); | |
7b24d861 | 1094 | spin_lock_init(&resv_map->lock); |
84afd99b | 1095 | INIT_LIST_HEAD(&resv_map->regions); |
bf491692 | 1096 | init_rwsem(&resv_map->rw_sema); |
84afd99b | 1097 | |
5e911373 | 1098 | resv_map->adds_in_progress = 0; |
e9fe92ae MA |
1099 | /* |
1100 | * Initialize these to 0. On shared mappings, 0's here indicate these | |
1101 | * fields don't do cgroup accounting. On private mappings, these will be | |
1102 | * re-initialized to the proper values, to indicate that hugetlb cgroup | |
1103 | * reservations are to be un-charged from here. | |
1104 | */ | |
1105 | resv_map_set_hugetlb_cgroup_uncharge_info(resv_map, NULL, NULL); | |
5e911373 MK |
1106 | |
1107 | INIT_LIST_HEAD(&resv_map->region_cache); | |
1108 | list_add(&rg->link, &resv_map->region_cache); | |
1109 | resv_map->region_cache_count = 1; | |
1110 | ||
84afd99b AW |
1111 | return resv_map; |
1112 | } | |
1113 | ||
9119a41e | 1114 | void resv_map_release(struct kref *ref) |
84afd99b AW |
1115 | { |
1116 | struct resv_map *resv_map = container_of(ref, struct resv_map, refs); | |
5e911373 MK |
1117 | struct list_head *head = &resv_map->region_cache; |
1118 | struct file_region *rg, *trg; | |
84afd99b AW |
1119 | |
1120 | /* Clear out any active regions before we release the map. */ | |
feba16e2 | 1121 | region_del(resv_map, 0, LONG_MAX); |
5e911373 MK |
1122 | |
1123 | /* ... and any entries left in the cache */ | |
1124 | list_for_each_entry_safe(rg, trg, head, link) { | |
1125 | list_del(&rg->link); | |
1126 | kfree(rg); | |
1127 | } | |
1128 | ||
1129 | VM_BUG_ON(resv_map->adds_in_progress); | |
1130 | ||
84afd99b AW |
1131 | kfree(resv_map); |
1132 | } | |
1133 | ||
4e35f483 JK |
1134 | static inline struct resv_map *inode_resv_map(struct inode *inode) |
1135 | { | |
f27a5136 MK |
1136 | /* |
1137 | * At inode evict time, i_mapping may not point to the original | |
1138 | * address space within the inode. This original address space | |
1139 | * contains the pointer to the resv_map. So, always use the | |
1140 | * address space embedded within the inode. | |
1141 | * The VERY common case is inode->mapping == &inode->i_data but, | |
1142 | * this may not be true for device special inodes. | |
1143 | */ | |
1144 | return (struct resv_map *)(&inode->i_data)->private_data; | |
4e35f483 JK |
1145 | } |
1146 | ||
84afd99b | 1147 | static struct resv_map *vma_resv_map(struct vm_area_struct *vma) |
a1e78772 | 1148 | { |
81d1b09c | 1149 | VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); |
4e35f483 JK |
1150 | if (vma->vm_flags & VM_MAYSHARE) { |
1151 | struct address_space *mapping = vma->vm_file->f_mapping; | |
1152 | struct inode *inode = mapping->host; | |
1153 | ||
1154 | return inode_resv_map(inode); | |
1155 | ||
1156 | } else { | |
84afd99b AW |
1157 | return (struct resv_map *)(get_vma_private_data(vma) & |
1158 | ~HPAGE_RESV_MASK); | |
4e35f483 | 1159 | } |
a1e78772 MG |
1160 | } |
1161 | ||
84afd99b | 1162 | static void set_vma_resv_map(struct vm_area_struct *vma, struct resv_map *map) |
a1e78772 | 1163 | { |
81d1b09c SL |
1164 | VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); |
1165 | VM_BUG_ON_VMA(vma->vm_flags & VM_MAYSHARE, vma); | |
a1e78772 | 1166 | |
92fe9dcb | 1167 | set_vma_private_data(vma, (unsigned long)map); |
04f2cbe3 MG |
1168 | } |
1169 | ||
1170 | static void set_vma_resv_flags(struct vm_area_struct *vma, unsigned long flags) | |
1171 | { | |
81d1b09c SL |
1172 | VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); |
1173 | VM_BUG_ON_VMA(vma->vm_flags & VM_MAYSHARE, vma); | |
e7c4b0bf AW |
1174 | |
1175 | set_vma_private_data(vma, get_vma_private_data(vma) | flags); | |
04f2cbe3 MG |
1176 | } |
1177 | ||
1178 | static int is_vma_resv_set(struct vm_area_struct *vma, unsigned long flag) | |
1179 | { | |
81d1b09c | 1180 | VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); |
e7c4b0bf AW |
1181 | |
1182 | return (get_vma_private_data(vma) & flag) != 0; | |
a1e78772 MG |
1183 | } |
1184 | ||
8d9bfb26 | 1185 | void hugetlb_dup_vma_private(struct vm_area_struct *vma) |
a1e78772 | 1186 | { |
81d1b09c | 1187 | VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); |
8d9bfb26 MK |
1188 | /* |
1189 | * Clear vm_private_data | |
612b8a31 MK |
1190 | * - For shared mappings this is a per-vma semaphore that may be |
1191 | * allocated in a subsequent call to hugetlb_vm_op_open. | |
1192 | * Before clearing, make sure pointer is not associated with vma | |
1193 | * as this will leak the structure. This is the case when called | |
1194 | * via clear_vma_resv_huge_pages() and hugetlb_vm_op_open has already | |
1195 | * been called to allocate a new structure. | |
8d9bfb26 MK |
1196 | * - For MAP_PRIVATE mappings, this is the reserve map which does |
1197 | * not apply to children. Faults generated by the children are | |
1198 | * not guaranteed to succeed, even if read-only. | |
8d9bfb26 | 1199 | */ |
612b8a31 MK |
1200 | if (vma->vm_flags & VM_MAYSHARE) { |
1201 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; | |
1202 | ||
1203 | if (vma_lock && vma_lock->vma != vma) | |
1204 | vma->vm_private_data = NULL; | |
1205 | } else | |
1206 | vma->vm_private_data = NULL; | |
a1e78772 MG |
1207 | } |
1208 | ||
550a7d60 MA |
1209 | /* |
1210 | * Reset and decrement one ref on hugepage private reservation. | |
8651a137 | 1211 | * Called with mm->mmap_lock writer semaphore held. |
550a7d60 MA |
1212 | * This function should be only used by move_vma() and operate on |
1213 | * same sized vma. It should never come here with last ref on the | |
1214 | * reservation. | |
1215 | */ | |
1216 | void clear_vma_resv_huge_pages(struct vm_area_struct *vma) | |
1217 | { | |
1218 | /* | |
1219 | * Clear the old hugetlb private page reservation. | |
1220 | * It has already been transferred to new_vma. | |
1221 | * | |
1222 | * During a mremap() operation of a hugetlb vma we call move_vma() | |
1223 | * which copies vma into new_vma and unmaps vma. After the copy | |
1224 | * operation both new_vma and vma share a reference to the resv_map | |
1225 | * struct, and at that point vma is about to be unmapped. We don't | |
1226 | * want to return the reservation to the pool at unmap of vma because | |
1227 | * the reservation still lives on in new_vma, so simply decrement the | |
1228 | * ref here and remove the resv_map reference from this vma. | |
1229 | */ | |
1230 | struct resv_map *reservations = vma_resv_map(vma); | |
1231 | ||
afe041c2 BQM |
1232 | if (reservations && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { |
1233 | resv_map_put_hugetlb_cgroup_uncharge_info(reservations); | |
550a7d60 | 1234 | kref_put(&reservations->refs, resv_map_release); |
afe041c2 | 1235 | } |
550a7d60 | 1236 | |
8d9bfb26 | 1237 | hugetlb_dup_vma_private(vma); |
550a7d60 MA |
1238 | } |
1239 | ||
a1e78772 | 1240 | /* Returns true if the VMA has associated reserve pages */ |
559ec2f8 | 1241 | static bool vma_has_reserves(struct vm_area_struct *vma, long chg) |
a1e78772 | 1242 | { |
af0ed73e JK |
1243 | if (vma->vm_flags & VM_NORESERVE) { |
1244 | /* | |
1245 | * This address is already reserved by other process(chg == 0), | |
1246 | * so, we should decrement reserved count. Without decrementing, | |
1247 | * reserve count remains after releasing inode, because this | |
1248 | * allocated page will go into page cache and is regarded as | |
1249 | * coming from reserved pool in releasing step. Currently, we | |
1250 | * don't have any other solution to deal with this situation | |
1251 | * properly, so add work-around here. | |
1252 | */ | |
1253 | if (vma->vm_flags & VM_MAYSHARE && chg == 0) | |
559ec2f8 | 1254 | return true; |
af0ed73e | 1255 | else |
559ec2f8 | 1256 | return false; |
af0ed73e | 1257 | } |
a63884e9 JK |
1258 | |
1259 | /* Shared mappings always use reserves */ | |
1fb1b0e9 MK |
1260 | if (vma->vm_flags & VM_MAYSHARE) { |
1261 | /* | |
1262 | * We know VM_NORESERVE is not set. Therefore, there SHOULD | |
1263 | * be a region map for all pages. The only situation where | |
1264 | * there is no region map is if a hole was punched via | |
7c8de358 | 1265 | * fallocate. In this case, there really are no reserves to |
1fb1b0e9 MK |
1266 | * use. This situation is indicated if chg != 0. |
1267 | */ | |
1268 | if (chg) | |
1269 | return false; | |
1270 | else | |
1271 | return true; | |
1272 | } | |
a63884e9 JK |
1273 | |
1274 | /* | |
1275 | * Only the process that called mmap() has reserves for | |
1276 | * private mappings. | |
1277 | */ | |
67961f9d MK |
1278 | if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { |
1279 | /* | |
1280 | * Like the shared case above, a hole punch or truncate | |
1281 | * could have been performed on the private mapping. | |
1282 | * Examine the value of chg to determine if reserves | |
1283 | * actually exist or were previously consumed. | |
1284 | * Very Subtle - The value of chg comes from a previous | |
1285 | * call to vma_needs_reserves(). The reserve map for | |
1286 | * private mappings has different (opposite) semantics | |
1287 | * than that of shared mappings. vma_needs_reserves() | |
1288 | * has already taken this difference in semantics into | |
1289 | * account. Therefore, the meaning of chg is the same | |
1290 | * as in the shared case above. Code could easily be | |
1291 | * combined, but keeping it separate draws attention to | |
1292 | * subtle differences. | |
1293 | */ | |
1294 | if (chg) | |
1295 | return false; | |
1296 | else | |
1297 | return true; | |
1298 | } | |
a63884e9 | 1299 | |
559ec2f8 | 1300 | return false; |
a1e78772 MG |
1301 | } |
1302 | ||
240d67a8 | 1303 | static void enqueue_hugetlb_folio(struct hstate *h, struct folio *folio) |
1da177e4 | 1304 | { |
240d67a8 | 1305 | int nid = folio_nid(folio); |
9487ca60 MK |
1306 | |
1307 | lockdep_assert_held(&hugetlb_lock); | |
240d67a8 | 1308 | VM_BUG_ON_FOLIO(folio_ref_count(folio), folio); |
b65a4eda | 1309 | |
240d67a8 | 1310 | list_move(&folio->lru, &h->hugepage_freelists[nid]); |
a5516438 AK |
1311 | h->free_huge_pages++; |
1312 | h->free_huge_pages_node[nid]++; | |
240d67a8 | 1313 | folio_set_hugetlb_freed(folio); |
1da177e4 LT |
1314 | } |
1315 | ||
a36f1e90 SK |
1316 | static struct folio *dequeue_hugetlb_folio_node_exact(struct hstate *h, |
1317 | int nid) | |
bf50bab2 | 1318 | { |
a36f1e90 | 1319 | struct folio *folio; |
1a08ae36 | 1320 | bool pin = !!(current->flags & PF_MEMALLOC_PIN); |
bbe88753 | 1321 | |
9487ca60 | 1322 | lockdep_assert_held(&hugetlb_lock); |
a36f1e90 SK |
1323 | list_for_each_entry(folio, &h->hugepage_freelists[nid], lru) { |
1324 | if (pin && !folio_is_longterm_pinnable(folio)) | |
bbe88753 | 1325 | continue; |
bf50bab2 | 1326 | |
a36f1e90 | 1327 | if (folio_test_hwpoison(folio)) |
6664bfc8 WY |
1328 | continue; |
1329 | ||
a36f1e90 SK |
1330 | list_move(&folio->lru, &h->hugepage_activelist); |
1331 | folio_ref_unfreeze(folio, 1); | |
1332 | folio_clear_hugetlb_freed(folio); | |
6664bfc8 WY |
1333 | h->free_huge_pages--; |
1334 | h->free_huge_pages_node[nid]--; | |
a36f1e90 | 1335 | return folio; |
bbe88753 JK |
1336 | } |
1337 | ||
6664bfc8 | 1338 | return NULL; |
bf50bab2 NH |
1339 | } |
1340 | ||
a36f1e90 SK |
1341 | static struct folio *dequeue_hugetlb_folio_nodemask(struct hstate *h, gfp_t gfp_mask, |
1342 | int nid, nodemask_t *nmask) | |
94310cbc | 1343 | { |
3e59fcb0 MH |
1344 | unsigned int cpuset_mems_cookie; |
1345 | struct zonelist *zonelist; | |
1346 | struct zone *zone; | |
1347 | struct zoneref *z; | |
98fa15f3 | 1348 | int node = NUMA_NO_NODE; |
94310cbc | 1349 | |
3e59fcb0 MH |
1350 | zonelist = node_zonelist(nid, gfp_mask); |
1351 | ||
1352 | retry_cpuset: | |
1353 | cpuset_mems_cookie = read_mems_allowed_begin(); | |
1354 | for_each_zone_zonelist_nodemask(zone, z, zonelist, gfp_zone(gfp_mask), nmask) { | |
a36f1e90 | 1355 | struct folio *folio; |
3e59fcb0 MH |
1356 | |
1357 | if (!cpuset_zone_allowed(zone, gfp_mask)) | |
1358 | continue; | |
1359 | /* | |
1360 | * no need to ask again on the same node. Pool is node rather than | |
1361 | * zone aware | |
1362 | */ | |
1363 | if (zone_to_nid(zone) == node) | |
1364 | continue; | |
1365 | node = zone_to_nid(zone); | |
94310cbc | 1366 | |
a36f1e90 SK |
1367 | folio = dequeue_hugetlb_folio_node_exact(h, node); |
1368 | if (folio) | |
1369 | return folio; | |
94310cbc | 1370 | } |
3e59fcb0 MH |
1371 | if (unlikely(read_mems_allowed_retry(cpuset_mems_cookie))) |
1372 | goto retry_cpuset; | |
1373 | ||
94310cbc AK |
1374 | return NULL; |
1375 | } | |
1376 | ||
8346d69d XH |
1377 | static unsigned long available_huge_pages(struct hstate *h) |
1378 | { | |
1379 | return h->free_huge_pages - h->resv_huge_pages; | |
1380 | } | |
1381 | ||
ff7d853b | 1382 | static struct folio *dequeue_hugetlb_folio_vma(struct hstate *h, |
a5516438 | 1383 | struct vm_area_struct *vma, |
af0ed73e JK |
1384 | unsigned long address, int avoid_reserve, |
1385 | long chg) | |
1da177e4 | 1386 | { |
a36f1e90 | 1387 | struct folio *folio = NULL; |
480eccf9 | 1388 | struct mempolicy *mpol; |
04ec6264 | 1389 | gfp_t gfp_mask; |
3e59fcb0 | 1390 | nodemask_t *nodemask; |
04ec6264 | 1391 | int nid; |
1da177e4 | 1392 | |
a1e78772 MG |
1393 | /* |
1394 | * A child process with MAP_PRIVATE mappings created by their parent | |
1395 | * have no page reserves. This check ensures that reservations are | |
1396 | * not "stolen". The child may still get SIGKILLed | |
1397 | */ | |
8346d69d | 1398 | if (!vma_has_reserves(vma, chg) && !available_huge_pages(h)) |
c0ff7453 | 1399 | goto err; |
a1e78772 | 1400 | |
04f2cbe3 | 1401 | /* If reserves cannot be used, ensure enough pages are in the pool */ |
8346d69d | 1402 | if (avoid_reserve && !available_huge_pages(h)) |
6eab04a8 | 1403 | goto err; |
04f2cbe3 | 1404 | |
04ec6264 VB |
1405 | gfp_mask = htlb_alloc_mask(h); |
1406 | nid = huge_node(vma, address, gfp_mask, &mpol, &nodemask); | |
cfcaa66f BW |
1407 | |
1408 | if (mpol_is_preferred_many(mpol)) { | |
a36f1e90 SK |
1409 | folio = dequeue_hugetlb_folio_nodemask(h, gfp_mask, |
1410 | nid, nodemask); | |
cfcaa66f BW |
1411 | |
1412 | /* Fallback to all nodes if page==NULL */ | |
1413 | nodemask = NULL; | |
1414 | } | |
1415 | ||
a36f1e90 SK |
1416 | if (!folio) |
1417 | folio = dequeue_hugetlb_folio_nodemask(h, gfp_mask, | |
1418 | nid, nodemask); | |
cfcaa66f | 1419 | |
a36f1e90 SK |
1420 | if (folio && !avoid_reserve && vma_has_reserves(vma, chg)) { |
1421 | folio_set_hugetlb_restore_reserve(folio); | |
3e59fcb0 | 1422 | h->resv_huge_pages--; |
1da177e4 | 1423 | } |
cc9a6c87 | 1424 | |
52cd3b07 | 1425 | mpol_cond_put(mpol); |
ff7d853b | 1426 | return folio; |
cc9a6c87 MG |
1427 | |
1428 | err: | |
cc9a6c87 | 1429 | return NULL; |
1da177e4 LT |
1430 | } |
1431 | ||
1cac6f2c LC |
1432 | /* |
1433 | * common helper functions for hstate_next_node_to_{alloc|free}. | |
1434 | * We may have allocated or freed a huge page based on a different | |
1435 | * nodes_allowed previously, so h->next_node_to_{alloc|free} might | |
1436 | * be outside of *nodes_allowed. Ensure that we use an allowed | |
1437 | * node for alloc or free. | |
1438 | */ | |
1439 | static int next_node_allowed(int nid, nodemask_t *nodes_allowed) | |
1440 | { | |
0edaf86c | 1441 | nid = next_node_in(nid, *nodes_allowed); |
1cac6f2c LC |
1442 | VM_BUG_ON(nid >= MAX_NUMNODES); |
1443 | ||
1444 | return nid; | |
1445 | } | |
1446 | ||
1447 | static int get_valid_node_allowed(int nid, nodemask_t *nodes_allowed) | |
1448 | { | |
1449 | if (!node_isset(nid, *nodes_allowed)) | |
1450 | nid = next_node_allowed(nid, nodes_allowed); | |
1451 | return nid; | |
1452 | } | |
1453 | ||
1454 | /* | |
1455 | * returns the previously saved node ["this node"] from which to | |
1456 | * allocate a persistent huge page for the pool and advance the | |
1457 | * next node from which to allocate, handling wrap at end of node | |
1458 | * mask. | |
1459 | */ | |
1460 | static int hstate_next_node_to_alloc(struct hstate *h, | |
1461 | nodemask_t *nodes_allowed) | |
1462 | { | |
1463 | int nid; | |
1464 | ||
1465 | VM_BUG_ON(!nodes_allowed); | |
1466 | ||
1467 | nid = get_valid_node_allowed(h->next_nid_to_alloc, nodes_allowed); | |
1468 | h->next_nid_to_alloc = next_node_allowed(nid, nodes_allowed); | |
1469 | ||
1470 | return nid; | |
1471 | } | |
1472 | ||
1473 | /* | |
d5b43e96 | 1474 | * helper for remove_pool_hugetlb_folio() - return the previously saved |
1cac6f2c LC |
1475 | * node ["this node"] from which to free a huge page. Advance the |
1476 | * next node id whether or not we find a free huge page to free so | |
1477 | * that the next attempt to free addresses the next node. | |
1478 | */ | |
1479 | static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed) | |
1480 | { | |
1481 | int nid; | |
1482 | ||
1483 | VM_BUG_ON(!nodes_allowed); | |
1484 | ||
1485 | nid = get_valid_node_allowed(h->next_nid_to_free, nodes_allowed); | |
1486 | h->next_nid_to_free = next_node_allowed(nid, nodes_allowed); | |
1487 | ||
1488 | return nid; | |
1489 | } | |
1490 | ||
1491 | #define for_each_node_mask_to_alloc(hs, nr_nodes, node, mask) \ | |
1492 | for (nr_nodes = nodes_weight(*mask); \ | |
1493 | nr_nodes > 0 && \ | |
1494 | ((node = hstate_next_node_to_alloc(hs, mask)) || 1); \ | |
1495 | nr_nodes--) | |
1496 | ||
1497 | #define for_each_node_mask_to_free(hs, nr_nodes, node, mask) \ | |
1498 | for (nr_nodes = nodes_weight(*mask); \ | |
1499 | nr_nodes > 0 && \ | |
1500 | ((node = hstate_next_node_to_free(hs, mask)) || 1); \ | |
1501 | nr_nodes--) | |
1502 | ||
8531fc6f | 1503 | /* used to demote non-gigantic_huge pages as well */ |
911565b8 | 1504 | static void __destroy_compound_gigantic_folio(struct folio *folio, |
34d9e35b | 1505 | unsigned int order, bool demote) |
944d9fec LC |
1506 | { |
1507 | int i; | |
1508 | int nr_pages = 1 << order; | |
14455eab | 1509 | struct page *p; |
944d9fec | 1510 | |
46f27228 | 1511 | atomic_set(&folio->_entire_mapcount, 0); |
eec20426 | 1512 | atomic_set(&folio->_nr_pages_mapped, 0); |
94688e8e | 1513 | atomic_set(&folio->_pincount, 0); |
47e29d32 | 1514 | |
14455eab | 1515 | for (i = 1; i < nr_pages; i++) { |
911565b8 | 1516 | p = folio_page(folio, i); |
6c141973 | 1517 | p->flags &= ~PAGE_FLAGS_CHECK_AT_FREE; |
a01f4390 | 1518 | p->mapping = NULL; |
1d798ca3 | 1519 | clear_compound_head(p); |
34d9e35b MK |
1520 | if (!demote) |
1521 | set_page_refcounted(p); | |
944d9fec LC |
1522 | } |
1523 | ||
911565b8 | 1524 | __folio_clear_head(folio); |
944d9fec LC |
1525 | } |
1526 | ||
911565b8 | 1527 | static void destroy_compound_hugetlb_folio_for_demote(struct folio *folio, |
8531fc6f MK |
1528 | unsigned int order) |
1529 | { | |
911565b8 | 1530 | __destroy_compound_gigantic_folio(folio, order, true); |
8531fc6f MK |
1531 | } |
1532 | ||
1533 | #ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE | |
911565b8 | 1534 | static void destroy_compound_gigantic_folio(struct folio *folio, |
34d9e35b MK |
1535 | unsigned int order) |
1536 | { | |
911565b8 | 1537 | __destroy_compound_gigantic_folio(folio, order, false); |
34d9e35b MK |
1538 | } |
1539 | ||
7f325a8d | 1540 | static void free_gigantic_folio(struct folio *folio, unsigned int order) |
944d9fec | 1541 | { |
cf11e85f RG |
1542 | /* |
1543 | * If the page isn't allocated using the cma allocator, | |
1544 | * cma_release() returns false. | |
1545 | */ | |
dbda8fea | 1546 | #ifdef CONFIG_CMA |
7f325a8d SK |
1547 | int nid = folio_nid(folio); |
1548 | ||
1549 | if (cma_release(hugetlb_cma[nid], &folio->page, 1 << order)) | |
cf11e85f | 1550 | return; |
dbda8fea | 1551 | #endif |
cf11e85f | 1552 | |
7f325a8d | 1553 | free_contig_range(folio_pfn(folio), 1 << order); |
944d9fec LC |
1554 | } |
1555 | ||
4eb0716e | 1556 | #ifdef CONFIG_CONTIG_ALLOC |
19fc1a7e | 1557 | static struct folio *alloc_gigantic_folio(struct hstate *h, gfp_t gfp_mask, |
d9cc948f | 1558 | int nid, nodemask_t *nodemask) |
944d9fec | 1559 | { |
19fc1a7e | 1560 | struct page *page; |
04adbc3f | 1561 | unsigned long nr_pages = pages_per_huge_page(h); |
953f064a LX |
1562 | if (nid == NUMA_NO_NODE) |
1563 | nid = numa_mem_id(); | |
944d9fec | 1564 | |
dbda8fea BS |
1565 | #ifdef CONFIG_CMA |
1566 | { | |
cf11e85f RG |
1567 | int node; |
1568 | ||
953f064a LX |
1569 | if (hugetlb_cma[nid]) { |
1570 | page = cma_alloc(hugetlb_cma[nid], nr_pages, | |
1571 | huge_page_order(h), true); | |
cf11e85f | 1572 | if (page) |
19fc1a7e | 1573 | return page_folio(page); |
cf11e85f | 1574 | } |
953f064a LX |
1575 | |
1576 | if (!(gfp_mask & __GFP_THISNODE)) { | |
1577 | for_each_node_mask(node, *nodemask) { | |
1578 | if (node == nid || !hugetlb_cma[node]) | |
1579 | continue; | |
1580 | ||
1581 | page = cma_alloc(hugetlb_cma[node], nr_pages, | |
1582 | huge_page_order(h), true); | |
1583 | if (page) | |
19fc1a7e | 1584 | return page_folio(page); |
953f064a LX |
1585 | } |
1586 | } | |
cf11e85f | 1587 | } |
dbda8fea | 1588 | #endif |
cf11e85f | 1589 | |
19fc1a7e SK |
1590 | page = alloc_contig_pages(nr_pages, gfp_mask, nid, nodemask); |
1591 | return page ? page_folio(page) : NULL; | |
944d9fec LC |
1592 | } |
1593 | ||
4eb0716e | 1594 | #else /* !CONFIG_CONTIG_ALLOC */ |
19fc1a7e | 1595 | static struct folio *alloc_gigantic_folio(struct hstate *h, gfp_t gfp_mask, |
4eb0716e AG |
1596 | int nid, nodemask_t *nodemask) |
1597 | { | |
1598 | return NULL; | |
1599 | } | |
1600 | #endif /* CONFIG_CONTIG_ALLOC */ | |
944d9fec | 1601 | |
e1073d1e | 1602 | #else /* !CONFIG_ARCH_HAS_GIGANTIC_PAGE */ |
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 | } | |
7f325a8d SK |
1608 | static inline void free_gigantic_folio(struct folio *folio, |
1609 | unsigned int order) { } | |
911565b8 | 1610 | static inline void destroy_compound_gigantic_folio(struct folio *folio, |
d00181b9 | 1611 | unsigned int order) { } |
944d9fec LC |
1612 | #endif |
1613 | ||
32c87719 MK |
1614 | static inline void __clear_hugetlb_destructor(struct hstate *h, |
1615 | struct folio *folio) | |
1616 | { | |
1617 | lockdep_assert_held(&hugetlb_lock); | |
1618 | ||
9c5ccf2d | 1619 | folio_clear_hugetlb(folio); |
32c87719 MK |
1620 | } |
1621 | ||
6eb4e88a | 1622 | /* |
32c87719 MK |
1623 | * Remove hugetlb folio from lists. |
1624 | * If vmemmap exists for the folio, update dtor so that the folio appears | |
1625 | * as just a compound page. Otherwise, wait until after allocating vmemmap | |
1626 | * to update dtor. | |
34d9e35b | 1627 | * |
cfd5082b | 1628 | * A reference is held on the folio, except in the case of demote. |
6eb4e88a MK |
1629 | * |
1630 | * Must be called with hugetlb lock held. | |
1631 | */ | |
cfd5082b | 1632 | static void __remove_hugetlb_folio(struct hstate *h, struct folio *folio, |
34d9e35b MK |
1633 | bool adjust_surplus, |
1634 | bool demote) | |
6eb4e88a | 1635 | { |
cfd5082b | 1636 | int nid = folio_nid(folio); |
6eb4e88a | 1637 | |
f074732d SK |
1638 | VM_BUG_ON_FOLIO(hugetlb_cgroup_from_folio(folio), folio); |
1639 | VM_BUG_ON_FOLIO(hugetlb_cgroup_from_folio_rsvd(folio), folio); | |
6eb4e88a | 1640 | |
9487ca60 | 1641 | lockdep_assert_held(&hugetlb_lock); |
6eb4e88a MK |
1642 | if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) |
1643 | return; | |
1644 | ||
cfd5082b | 1645 | list_del(&folio->lru); |
6eb4e88a | 1646 | |
cfd5082b | 1647 | if (folio_test_hugetlb_freed(folio)) { |
6eb4e88a MK |
1648 | h->free_huge_pages--; |
1649 | h->free_huge_pages_node[nid]--; | |
1650 | } | |
1651 | if (adjust_surplus) { | |
1652 | h->surplus_huge_pages--; | |
1653 | h->surplus_huge_pages_node[nid]--; | |
1654 | } | |
1655 | ||
e32d20c0 | 1656 | /* |
32c87719 MK |
1657 | * We can only clear the hugetlb destructor after allocating vmemmap |
1658 | * pages. Otherwise, someone (memory error handling) may try to write | |
1659 | * to tail struct pages. | |
1660 | */ | |
1661 | if (!folio_test_hugetlb_vmemmap_optimized(folio)) | |
1662 | __clear_hugetlb_destructor(h, folio); | |
1663 | ||
1664 | /* | |
1665 | * In the case of demote we do not ref count the page as it will soon | |
1666 | * be turned into a page of smaller size. | |
e32d20c0 | 1667 | */ |
34d9e35b | 1668 | if (!demote) |
cfd5082b | 1669 | folio_ref_unfreeze(folio, 1); |
6eb4e88a MK |
1670 | |
1671 | h->nr_huge_pages--; | |
1672 | h->nr_huge_pages_node[nid]--; | |
1673 | } | |
1674 | ||
cfd5082b | 1675 | static void remove_hugetlb_folio(struct hstate *h, struct folio *folio, |
34d9e35b MK |
1676 | bool adjust_surplus) |
1677 | { | |
cfd5082b | 1678 | __remove_hugetlb_folio(h, folio, adjust_surplus, false); |
34d9e35b MK |
1679 | } |
1680 | ||
cfd5082b | 1681 | static void remove_hugetlb_folio_for_demote(struct hstate *h, struct folio *folio, |
8531fc6f MK |
1682 | bool adjust_surplus) |
1683 | { | |
cfd5082b | 1684 | __remove_hugetlb_folio(h, folio, adjust_surplus, true); |
8531fc6f MK |
1685 | } |
1686 | ||
2f6c57d6 | 1687 | static void add_hugetlb_folio(struct hstate *h, struct folio *folio, |
ad2fa371 MS |
1688 | bool adjust_surplus) |
1689 | { | |
1690 | int zeroed; | |
2f6c57d6 | 1691 | int nid = folio_nid(folio); |
ad2fa371 | 1692 | |
2f6c57d6 | 1693 | VM_BUG_ON_FOLIO(!folio_test_hugetlb_vmemmap_optimized(folio), folio); |
ad2fa371 MS |
1694 | |
1695 | lockdep_assert_held(&hugetlb_lock); | |
1696 | ||
2f6c57d6 | 1697 | INIT_LIST_HEAD(&folio->lru); |
ad2fa371 MS |
1698 | h->nr_huge_pages++; |
1699 | h->nr_huge_pages_node[nid]++; | |
1700 | ||
1701 | if (adjust_surplus) { | |
1702 | h->surplus_huge_pages++; | |
1703 | h->surplus_huge_pages_node[nid]++; | |
1704 | } | |
1705 | ||
9c5ccf2d | 1706 | folio_set_hugetlb(folio); |
2f6c57d6 | 1707 | folio_change_private(folio, NULL); |
a9e1eab2 | 1708 | /* |
2f6c57d6 SK |
1709 | * We have to set hugetlb_vmemmap_optimized again as above |
1710 | * folio_change_private(folio, NULL) cleared it. | |
a9e1eab2 | 1711 | */ |
2f6c57d6 | 1712 | folio_set_hugetlb_vmemmap_optimized(folio); |
ad2fa371 MS |
1713 | |
1714 | /* | |
2f6c57d6 | 1715 | * This folio is about to be managed by the hugetlb allocator and |
b65a4eda MK |
1716 | * should have no users. Drop our reference, and check for others |
1717 | * just in case. | |
ad2fa371 | 1718 | */ |
2f6c57d6 SK |
1719 | zeroed = folio_put_testzero(folio); |
1720 | if (unlikely(!zeroed)) | |
b65a4eda | 1721 | /* |
454a00c4 MWO |
1722 | * It is VERY unlikely soneone else has taken a ref |
1723 | * on the folio. In this case, we simply return as | |
1724 | * free_huge_folio() will be called when this other ref | |
1725 | * is dropped. | |
b65a4eda MK |
1726 | */ |
1727 | return; | |
1728 | ||
2f6c57d6 | 1729 | arch_clear_hugepage_flags(&folio->page); |
240d67a8 | 1730 | enqueue_hugetlb_folio(h, folio); |
ad2fa371 MS |
1731 | } |
1732 | ||
6f6956cf SK |
1733 | static void __update_and_free_hugetlb_folio(struct hstate *h, |
1734 | struct folio *folio) | |
6af2acb6 | 1735 | { |
32c87719 | 1736 | bool clear_dtor = folio_test_hugetlb_vmemmap_optimized(folio); |
a5516438 | 1737 | |
4eb0716e | 1738 | if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) |
944d9fec | 1739 | return; |
18229df5 | 1740 | |
161df60e NH |
1741 | /* |
1742 | * If we don't know which subpages are hwpoisoned, we can't free | |
1743 | * the hugepage, so it's leaked intentionally. | |
1744 | */ | |
7f325a8d | 1745 | if (folio_test_hugetlb_raw_hwp_unreliable(folio)) |
161df60e NH |
1746 | return; |
1747 | ||
d8f5f7e4 MK |
1748 | /* |
1749 | * If folio is not vmemmap optimized (!clear_dtor), then the folio | |
c5ad3233 | 1750 | * is no longer identified as a hugetlb page. hugetlb_vmemmap_restore_folio |
d8f5f7e4 MK |
1751 | * can only be passed hugetlb pages and will BUG otherwise. |
1752 | */ | |
c5ad3233 | 1753 | if (clear_dtor && hugetlb_vmemmap_restore_folio(h, folio)) { |
ad2fa371 MS |
1754 | spin_lock_irq(&hugetlb_lock); |
1755 | /* | |
1756 | * If we cannot allocate vmemmap pages, just refuse to free the | |
1757 | * page and put the page back on the hugetlb free list and treat | |
1758 | * as a surplus page. | |
1759 | */ | |
7f325a8d | 1760 | add_hugetlb_folio(h, folio, true); |
ad2fa371 MS |
1761 | spin_unlock_irq(&hugetlb_lock); |
1762 | return; | |
1763 | } | |
1764 | ||
161df60e NH |
1765 | /* |
1766 | * Move PageHWPoison flag from head page to the raw error pages, | |
1767 | * which makes any healthy subpages reusable. | |
1768 | */ | |
911565b8 | 1769 | if (unlikely(folio_test_hwpoison(folio))) |
2ff6cece | 1770 | folio_clear_hugetlb_hwpoison(folio); |
161df60e | 1771 | |
32c87719 MK |
1772 | /* |
1773 | * If vmemmap pages were allocated above, then we need to clear the | |
1774 | * hugetlb destructor under the hugetlb lock. | |
1775 | */ | |
1776 | if (clear_dtor) { | |
1777 | spin_lock_irq(&hugetlb_lock); | |
1778 | __clear_hugetlb_destructor(h, folio); | |
1779 | spin_unlock_irq(&hugetlb_lock); | |
1780 | } | |
1781 | ||
a01f4390 MK |
1782 | /* |
1783 | * Non-gigantic pages demoted from CMA allocated gigantic pages | |
7f325a8d | 1784 | * need to be given back to CMA in free_gigantic_folio. |
a01f4390 MK |
1785 | */ |
1786 | if (hstate_is_gigantic(h) || | |
2f6c57d6 | 1787 | hugetlb_cma_folio(folio, huge_page_order(h))) { |
911565b8 | 1788 | destroy_compound_gigantic_folio(folio, huge_page_order(h)); |
7f325a8d | 1789 | free_gigantic_folio(folio, huge_page_order(h)); |
944d9fec | 1790 | } else { |
6f6956cf | 1791 | __free_pages(&folio->page, huge_page_order(h)); |
944d9fec | 1792 | } |
6af2acb6 AL |
1793 | } |
1794 | ||
b65d4adb | 1795 | /* |
d6ef19e2 | 1796 | * As update_and_free_hugetlb_folio() can be called under any context, so we cannot |
b65d4adb MS |
1797 | * use GFP_KERNEL to allocate vmemmap pages. However, we can defer the |
1798 | * actual freeing in a workqueue to prevent from using GFP_ATOMIC to allocate | |
1799 | * the vmemmap pages. | |
1800 | * | |
1801 | * free_hpage_workfn() locklessly retrieves the linked list of pages to be | |
1802 | * freed and frees them one-by-one. As the page->mapping pointer is going | |
1803 | * to be cleared in free_hpage_workfn() anyway, it is reused as the llist_node | |
1804 | * structure of a lockless linked list of huge pages to be freed. | |
1805 | */ | |
1806 | static LLIST_HEAD(hpage_freelist); | |
1807 | ||
1808 | static void free_hpage_workfn(struct work_struct *work) | |
1809 | { | |
1810 | struct llist_node *node; | |
1811 | ||
1812 | node = llist_del_all(&hpage_freelist); | |
1813 | ||
1814 | while (node) { | |
3ec145f9 | 1815 | struct folio *folio; |
b65d4adb MS |
1816 | struct hstate *h; |
1817 | ||
3ec145f9 MWO |
1818 | folio = container_of((struct address_space **)node, |
1819 | struct folio, mapping); | |
b65d4adb | 1820 | node = node->next; |
3ec145f9 | 1821 | folio->mapping = NULL; |
b65d4adb | 1822 | /* |
affd26b1 SK |
1823 | * The VM_BUG_ON_FOLIO(!folio_test_hugetlb(folio), folio) in |
1824 | * folio_hstate() is going to trigger because a previous call to | |
9c5ccf2d MWO |
1825 | * remove_hugetlb_folio() will clear the hugetlb bit, so do |
1826 | * not use folio_hstate() directly. | |
b65d4adb | 1827 | */ |
3ec145f9 | 1828 | h = size_to_hstate(folio_size(folio)); |
b65d4adb | 1829 | |
3ec145f9 | 1830 | __update_and_free_hugetlb_folio(h, folio); |
b65d4adb MS |
1831 | |
1832 | cond_resched(); | |
1833 | } | |
1834 | } | |
1835 | static DECLARE_WORK(free_hpage_work, free_hpage_workfn); | |
1836 | ||
1837 | static inline void flush_free_hpage_work(struct hstate *h) | |
1838 | { | |
6213834c | 1839 | if (hugetlb_vmemmap_optimizable(h)) |
b65d4adb MS |
1840 | flush_work(&free_hpage_work); |
1841 | } | |
1842 | ||
d6ef19e2 | 1843 | static void update_and_free_hugetlb_folio(struct hstate *h, struct folio *folio, |
b65d4adb MS |
1844 | bool atomic) |
1845 | { | |
d6ef19e2 | 1846 | if (!folio_test_hugetlb_vmemmap_optimized(folio) || !atomic) { |
6f6956cf | 1847 | __update_and_free_hugetlb_folio(h, folio); |
b65d4adb MS |
1848 | return; |
1849 | } | |
1850 | ||
1851 | /* | |
1852 | * Defer freeing to avoid using GFP_ATOMIC to allocate vmemmap pages. | |
1853 | * | |
1854 | * Only call schedule_work() if hpage_freelist is previously | |
1855 | * empty. Otherwise, schedule_work() had been called but the workfn | |
1856 | * hasn't retrieved the list yet. | |
1857 | */ | |
d6ef19e2 | 1858 | if (llist_add((struct llist_node *)&folio->mapping, &hpage_freelist)) |
b65d4adb MS |
1859 | schedule_work(&free_hpage_work); |
1860 | } | |
1861 | ||
cfb8c750 MK |
1862 | static void bulk_vmemmap_restore_error(struct hstate *h, |
1863 | struct list_head *folio_list, | |
1864 | struct list_head *non_hvo_folios) | |
10c6ec49 | 1865 | { |
04bbfd84 | 1866 | struct folio *folio, *t_folio; |
10c6ec49 | 1867 | |
cfb8c750 MK |
1868 | if (!list_empty(non_hvo_folios)) { |
1869 | /* | |
1870 | * Free any restored hugetlb pages so that restore of the | |
1871 | * entire list can be retried. | |
1872 | * The idea is that in the common case of ENOMEM errors freeing | |
1873 | * hugetlb pages with vmemmap we will free up memory so that we | |
1874 | * can allocate vmemmap for more hugetlb pages. | |
1875 | */ | |
1876 | list_for_each_entry_safe(folio, t_folio, non_hvo_folios, lru) { | |
1877 | list_del(&folio->lru); | |
1878 | spin_lock_irq(&hugetlb_lock); | |
1879 | __clear_hugetlb_destructor(h, folio); | |
1880 | spin_unlock_irq(&hugetlb_lock); | |
1881 | update_and_free_hugetlb_folio(h, folio, false); | |
1882 | cond_resched(); | |
1883 | } | |
1884 | } else { | |
1885 | /* | |
1886 | * In the case where there are no folios which can be | |
1887 | * immediately freed, we loop through the list trying to restore | |
1888 | * vmemmap individually in the hope that someone elsewhere may | |
1889 | * have done something to cause success (such as freeing some | |
1890 | * memory). If unable to restore a hugetlb page, the hugetlb | |
1891 | * page is made a surplus page and removed from the list. | |
1892 | * If are able to restore vmemmap and free one hugetlb page, we | |
1893 | * quit processing the list to retry the bulk operation. | |
1894 | */ | |
1895 | list_for_each_entry_safe(folio, t_folio, folio_list, lru) | |
c5ad3233 | 1896 | if (hugetlb_vmemmap_restore_folio(h, folio)) { |
cfb8c750 | 1897 | list_del(&folio->lru); |
d2cf88c2 MK |
1898 | spin_lock_irq(&hugetlb_lock); |
1899 | add_hugetlb_folio(h, folio, true); | |
1900 | spin_unlock_irq(&hugetlb_lock); | |
cfb8c750 MK |
1901 | } else { |
1902 | list_del(&folio->lru); | |
1903 | spin_lock_irq(&hugetlb_lock); | |
1904 | __clear_hugetlb_destructor(h, folio); | |
1905 | spin_unlock_irq(&hugetlb_lock); | |
1906 | update_and_free_hugetlb_folio(h, folio, false); | |
1907 | cond_resched(); | |
1908 | break; | |
1909 | } | |
d2cf88c2 | 1910 | } |
cfb8c750 MK |
1911 | } |
1912 | ||
1913 | static void update_and_free_pages_bulk(struct hstate *h, | |
1914 | struct list_head *folio_list) | |
1915 | { | |
1916 | long ret; | |
1917 | struct folio *folio, *t_folio; | |
1918 | LIST_HEAD(non_hvo_folios); | |
d2cf88c2 MK |
1919 | |
1920 | /* | |
cfb8c750 MK |
1921 | * First allocate required vmemmmap (if necessary) for all folios. |
1922 | * Carefully handle errors and free up any available hugetlb pages | |
1923 | * in an effort to make forward progress. | |
d2cf88c2 | 1924 | */ |
cfb8c750 MK |
1925 | retry: |
1926 | ret = hugetlb_vmemmap_restore_folios(h, folio_list, &non_hvo_folios); | |
1927 | if (ret < 0) { | |
1928 | bulk_vmemmap_restore_error(h, folio_list, &non_hvo_folios); | |
1929 | goto retry; | |
1930 | } | |
1931 | ||
1932 | /* | |
1933 | * At this point, list should be empty, ret should be >= 0 and there | |
1934 | * should only be pages on the non_hvo_folios list. | |
1935 | * Do note that the non_hvo_folios list could be empty. | |
1936 | * Without HVO enabled, ret will be 0 and there is no need to call | |
1937 | * __clear_hugetlb_destructor as this was done previously. | |
1938 | */ | |
1939 | VM_WARN_ON(!list_empty(folio_list)); | |
1940 | VM_WARN_ON(ret < 0); | |
1941 | if (!list_empty(&non_hvo_folios) && ret) { | |
d2cf88c2 | 1942 | spin_lock_irq(&hugetlb_lock); |
cfb8c750 | 1943 | list_for_each_entry(folio, &non_hvo_folios, lru) |
d2cf88c2 MK |
1944 | __clear_hugetlb_destructor(h, folio); |
1945 | spin_unlock_irq(&hugetlb_lock); | |
1946 | } | |
1947 | ||
cfb8c750 | 1948 | list_for_each_entry_safe(folio, t_folio, &non_hvo_folios, lru) { |
d6ef19e2 | 1949 | update_and_free_hugetlb_folio(h, folio, false); |
10c6ec49 MK |
1950 | cond_resched(); |
1951 | } | |
1952 | } | |
1953 | ||
e5ff2159 AK |
1954 | struct hstate *size_to_hstate(unsigned long size) |
1955 | { | |
1956 | struct hstate *h; | |
1957 | ||
1958 | for_each_hstate(h) { | |
1959 | if (huge_page_size(h) == size) | |
1960 | return h; | |
1961 | } | |
1962 | return NULL; | |
1963 | } | |
1964 | ||
454a00c4 | 1965 | void free_huge_folio(struct folio *folio) |
27a85ef1 | 1966 | { |
a5516438 AK |
1967 | /* |
1968 | * Can't pass hstate in here because it is called from the | |
1969 | * compound page destructor. | |
1970 | */ | |
0356c4b9 SK |
1971 | struct hstate *h = folio_hstate(folio); |
1972 | int nid = folio_nid(folio); | |
1973 | struct hugepage_subpool *spool = hugetlb_folio_subpool(folio); | |
07443a85 | 1974 | bool restore_reserve; |
db71ef79 | 1975 | unsigned long flags; |
27a85ef1 | 1976 | |
0356c4b9 SK |
1977 | VM_BUG_ON_FOLIO(folio_ref_count(folio), folio); |
1978 | VM_BUG_ON_FOLIO(folio_mapcount(folio), folio); | |
8ace22bc | 1979 | |
0356c4b9 SK |
1980 | hugetlb_set_folio_subpool(folio, NULL); |
1981 | if (folio_test_anon(folio)) | |
1982 | __ClearPageAnonExclusive(&folio->page); | |
1983 | folio->mapping = NULL; | |
1984 | restore_reserve = folio_test_hugetlb_restore_reserve(folio); | |
1985 | folio_clear_hugetlb_restore_reserve(folio); | |
27a85ef1 | 1986 | |
1c5ecae3 | 1987 | /* |
d6995da3 | 1988 | * If HPageRestoreReserve was set on page, page allocation consumed a |
0919e1b6 MK |
1989 | * reservation. If the page was associated with a subpool, there |
1990 | * would have been a page reserved in the subpool before allocation | |
1991 | * via hugepage_subpool_get_pages(). Since we are 'restoring' the | |
6c26d310 | 1992 | * reservation, do not call hugepage_subpool_put_pages() as this will |
0919e1b6 | 1993 | * remove the reserved page from the subpool. |
1c5ecae3 | 1994 | */ |
0919e1b6 MK |
1995 | if (!restore_reserve) { |
1996 | /* | |
1997 | * A return code of zero implies that the subpool will be | |
1998 | * under its minimum size if the reservation is not restored | |
1999 | * after page is free. Therefore, force restore_reserve | |
2000 | * operation. | |
2001 | */ | |
2002 | if (hugepage_subpool_put_pages(spool, 1) == 0) | |
2003 | restore_reserve = true; | |
2004 | } | |
1c5ecae3 | 2005 | |
db71ef79 | 2006 | spin_lock_irqsave(&hugetlb_lock, flags); |
0356c4b9 | 2007 | folio_clear_hugetlb_migratable(folio); |
d4ab0316 SK |
2008 | hugetlb_cgroup_uncharge_folio(hstate_index(h), |
2009 | pages_per_huge_page(h), folio); | |
2010 | hugetlb_cgroup_uncharge_folio_rsvd(hstate_index(h), | |
2011 | pages_per_huge_page(h), folio); | |
8cba9576 | 2012 | mem_cgroup_uncharge(folio); |
07443a85 JK |
2013 | if (restore_reserve) |
2014 | h->resv_huge_pages++; | |
2015 | ||
0356c4b9 | 2016 | if (folio_test_hugetlb_temporary(folio)) { |
cfd5082b | 2017 | remove_hugetlb_folio(h, folio, false); |
db71ef79 | 2018 | spin_unlock_irqrestore(&hugetlb_lock, flags); |
d6ef19e2 | 2019 | update_and_free_hugetlb_folio(h, folio, true); |
ab5ac90a | 2020 | } else if (h->surplus_huge_pages_node[nid]) { |
0edaecfa | 2021 | /* remove the page from active list */ |
cfd5082b | 2022 | remove_hugetlb_folio(h, folio, true); |
db71ef79 | 2023 | spin_unlock_irqrestore(&hugetlb_lock, flags); |
d6ef19e2 | 2024 | update_and_free_hugetlb_folio(h, folio, true); |
7893d1d5 | 2025 | } else { |
454a00c4 | 2026 | arch_clear_hugepage_flags(&folio->page); |
240d67a8 | 2027 | enqueue_hugetlb_folio(h, folio); |
db71ef79 | 2028 | spin_unlock_irqrestore(&hugetlb_lock, flags); |
c77c0a8a | 2029 | } |
c77c0a8a WL |
2030 | } |
2031 | ||
d3d99fcc OS |
2032 | /* |
2033 | * Must be called with the hugetlb lock held | |
2034 | */ | |
2035 | static void __prep_account_new_huge_page(struct hstate *h, int nid) | |
2036 | { | |
2037 | lockdep_assert_held(&hugetlb_lock); | |
2038 | h->nr_huge_pages++; | |
2039 | h->nr_huge_pages_node[nid]++; | |
2040 | } | |
2041 | ||
d67e32f2 | 2042 | static void init_new_hugetlb_folio(struct hstate *h, struct folio *folio) |
b7ba30c6 | 2043 | { |
d8f5f7e4 | 2044 | folio_set_hugetlb(folio); |
de656ed3 | 2045 | INIT_LIST_HEAD(&folio->lru); |
de656ed3 SK |
2046 | hugetlb_set_folio_subpool(folio, NULL); |
2047 | set_hugetlb_cgroup(folio, NULL); | |
2048 | set_hugetlb_cgroup_rsvd(folio, NULL); | |
d3d99fcc OS |
2049 | } |
2050 | ||
d67e32f2 MK |
2051 | static void __prep_new_hugetlb_folio(struct hstate *h, struct folio *folio) |
2052 | { | |
2053 | init_new_hugetlb_folio(h, folio); | |
c5ad3233 | 2054 | hugetlb_vmemmap_optimize_folio(h, folio); |
d67e32f2 MK |
2055 | } |
2056 | ||
d1c60955 | 2057 | static void prep_new_hugetlb_folio(struct hstate *h, struct folio *folio, int nid) |
d3d99fcc | 2058 | { |
de656ed3 | 2059 | __prep_new_hugetlb_folio(h, folio); |
db71ef79 | 2060 | spin_lock_irq(&hugetlb_lock); |
d3d99fcc | 2061 | __prep_account_new_huge_page(h, nid); |
db71ef79 | 2062 | spin_unlock_irq(&hugetlb_lock); |
b7ba30c6 AK |
2063 | } |
2064 | ||
d1c60955 SK |
2065 | static bool __prep_compound_gigantic_folio(struct folio *folio, |
2066 | unsigned int order, bool demote) | |
20a0307c | 2067 | { |
7118fc29 | 2068 | int i, j; |
20a0307c | 2069 | int nr_pages = 1 << order; |
14455eab | 2070 | struct page *p; |
20a0307c | 2071 | |
d1c60955 | 2072 | __folio_clear_reserved(folio); |
2b21624f | 2073 | for (i = 0; i < nr_pages; i++) { |
d1c60955 | 2074 | p = folio_page(folio, i); |
14455eab | 2075 | |
ef5a22be AA |
2076 | /* |
2077 | * For gigantic hugepages allocated through bootmem at | |
2078 | * boot, it's safer to be consistent with the not-gigantic | |
2079 | * hugepages and clear the PG_reserved bit from all tail pages | |
7c8de358 | 2080 | * too. Otherwise drivers using get_user_pages() to access tail |
ef5a22be AA |
2081 | * pages may get the reference counting wrong if they see |
2082 | * PG_reserved set on a tail page (despite the head page not | |
2083 | * having PG_reserved set). Enforcing this consistency between | |
2084 | * head and tail pages allows drivers to optimize away a check | |
2085 | * on the head page when they need know if put_page() is needed | |
2086 | * after get_user_pages(). | |
2087 | */ | |
7fb0728a MK |
2088 | if (i != 0) /* head page cleared above */ |
2089 | __ClearPageReserved(p); | |
7118fc29 MK |
2090 | /* |
2091 | * Subtle and very unlikely | |
2092 | * | |
2093 | * Gigantic 'page allocators' such as memblock or cma will | |
2094 | * return a set of pages with each page ref counted. We need | |
2095 | * to turn this set of pages into a compound page with tail | |
2096 | * page ref counts set to zero. Code such as speculative page | |
2097 | * cache adding could take a ref on a 'to be' tail page. | |
2098 | * We need to respect any increased ref count, and only set | |
2099 | * the ref count to zero if count is currently 1. If count | |
416d85ed MK |
2100 | * is not 1, we return an error. An error return indicates |
2101 | * the set of pages can not be converted to a gigantic page. | |
2102 | * The caller who allocated the pages should then discard the | |
2103 | * pages using the appropriate free interface. | |
34d9e35b MK |
2104 | * |
2105 | * In the case of demote, the ref count will be zero. | |
7118fc29 | 2106 | */ |
34d9e35b MK |
2107 | if (!demote) { |
2108 | if (!page_ref_freeze(p, 1)) { | |
2109 | pr_warn("HugeTLB page can not be used due to unexpected inflated ref count\n"); | |
2110 | goto out_error; | |
2111 | } | |
2112 | } else { | |
2113 | VM_BUG_ON_PAGE(page_count(p), p); | |
7118fc29 | 2114 | } |
2b21624f | 2115 | if (i != 0) |
d1c60955 | 2116 | set_compound_head(p, &folio->page); |
20a0307c | 2117 | } |
e3b7bf97 TS |
2118 | __folio_set_head(folio); |
2119 | /* we rely on prep_new_hugetlb_folio to set the destructor */ | |
2120 | folio_set_order(folio, order); | |
46f27228 | 2121 | atomic_set(&folio->_entire_mapcount, -1); |
eec20426 | 2122 | atomic_set(&folio->_nr_pages_mapped, 0); |
94688e8e | 2123 | atomic_set(&folio->_pincount, 0); |
7118fc29 MK |
2124 | return true; |
2125 | ||
2126 | out_error: | |
2b21624f MK |
2127 | /* undo page modifications made above */ |
2128 | for (j = 0; j < i; j++) { | |
d1c60955 | 2129 | p = folio_page(folio, j); |
2b21624f MK |
2130 | if (j != 0) |
2131 | clear_compound_head(p); | |
7118fc29 MK |
2132 | set_page_refcounted(p); |
2133 | } | |
2134 | /* need to clear PG_reserved on remaining tail pages */ | |
14455eab | 2135 | for (; j < nr_pages; j++) { |
d1c60955 | 2136 | p = folio_page(folio, j); |
7118fc29 | 2137 | __ClearPageReserved(p); |
14455eab | 2138 | } |
7118fc29 | 2139 | return false; |
20a0307c WF |
2140 | } |
2141 | ||
d1c60955 SK |
2142 | static bool prep_compound_gigantic_folio(struct folio *folio, |
2143 | unsigned int order) | |
34d9e35b | 2144 | { |
d1c60955 | 2145 | return __prep_compound_gigantic_folio(folio, order, false); |
34d9e35b MK |
2146 | } |
2147 | ||
d1c60955 | 2148 | static bool prep_compound_gigantic_folio_for_demote(struct folio *folio, |
8531fc6f MK |
2149 | unsigned int order) |
2150 | { | |
d1c60955 | 2151 | return __prep_compound_gigantic_folio(folio, order, true); |
8531fc6f MK |
2152 | } |
2153 | ||
7795912c AM |
2154 | /* |
2155 | * PageHuge() only returns true for hugetlbfs pages, but not for normal or | |
2156 | * transparent huge pages. See the PageTransHuge() documentation for more | |
2157 | * details. | |
2158 | */ | |
20a0307c WF |
2159 | int PageHuge(struct page *page) |
2160 | { | |
2d678c64 MWO |
2161 | struct folio *folio; |
2162 | ||
20a0307c WF |
2163 | if (!PageCompound(page)) |
2164 | return 0; | |
2d678c64 | 2165 | folio = page_folio(page); |
9c5ccf2d | 2166 | return folio_test_hugetlb(folio); |
20a0307c | 2167 | } |
43131e14 NH |
2168 | EXPORT_SYMBOL_GPL(PageHuge); |
2169 | ||
c0d0381a MK |
2170 | /* |
2171 | * Find and lock address space (mapping) in write mode. | |
2172 | * | |
336bf30e MK |
2173 | * Upon entry, the page is locked which means that page_mapping() is |
2174 | * stable. Due to locking order, we can only trylock_write. If we can | |
2175 | * not get the lock, simply return NULL to caller. | |
c0d0381a MK |
2176 | */ |
2177 | struct address_space *hugetlb_page_mapping_lock_write(struct page *hpage) | |
2178 | { | |
336bf30e | 2179 | struct address_space *mapping = page_mapping(hpage); |
c0d0381a | 2180 | |
c0d0381a MK |
2181 | if (!mapping) |
2182 | return mapping; | |
2183 | ||
c0d0381a MK |
2184 | if (i_mmap_trylock_write(mapping)) |
2185 | return mapping; | |
2186 | ||
336bf30e | 2187 | return NULL; |
c0d0381a MK |
2188 | } |
2189 | ||
19fc1a7e | 2190 | static struct folio *alloc_buddy_hugetlb_folio(struct hstate *h, |
f60858f9 MK |
2191 | gfp_t gfp_mask, int nid, nodemask_t *nmask, |
2192 | nodemask_t *node_alloc_noretry) | |
1da177e4 | 2193 | { |
af0fb9df | 2194 | int order = huge_page_order(h); |
1da177e4 | 2195 | struct page *page; |
f60858f9 | 2196 | bool alloc_try_hard = true; |
2b21624f | 2197 | bool retry = true; |
f96efd58 | 2198 | |
f60858f9 MK |
2199 | /* |
2200 | * By default we always try hard to allocate the page with | |
2201 | * __GFP_RETRY_MAYFAIL flag. However, if we are allocating pages in | |
2202 | * a loop (to adjust global huge page counts) and previous allocation | |
2203 | * failed, do not continue to try hard on the same node. Use the | |
2204 | * node_alloc_noretry bitmap to manage this state information. | |
2205 | */ | |
2206 | if (node_alloc_noretry && node_isset(nid, *node_alloc_noretry)) | |
2207 | alloc_try_hard = false; | |
2208 | gfp_mask |= __GFP_COMP|__GFP_NOWARN; | |
2209 | if (alloc_try_hard) | |
2210 | gfp_mask |= __GFP_RETRY_MAYFAIL; | |
af0fb9df MH |
2211 | if (nid == NUMA_NO_NODE) |
2212 | nid = numa_mem_id(); | |
2b21624f | 2213 | retry: |
84172f4b | 2214 | page = __alloc_pages(gfp_mask, order, nid, nmask); |
2b21624f MK |
2215 | |
2216 | /* Freeze head page */ | |
2217 | if (page && !page_ref_freeze(page, 1)) { | |
2218 | __free_pages(page, order); | |
2219 | if (retry) { /* retry once */ | |
2220 | retry = false; | |
2221 | goto retry; | |
2222 | } | |
2223 | /* WOW! twice in a row. */ | |
2224 | pr_warn("HugeTLB head page unexpected inflated ref count\n"); | |
2225 | page = NULL; | |
2226 | } | |
2227 | ||
f60858f9 MK |
2228 | /* |
2229 | * If we did not specify __GFP_RETRY_MAYFAIL, but still got a page this | |
2230 | * indicates an overall state change. Clear bit so that we resume | |
2231 | * normal 'try hard' allocations. | |
2232 | */ | |
2233 | if (node_alloc_noretry && page && !alloc_try_hard) | |
2234 | node_clear(nid, *node_alloc_noretry); | |
2235 | ||
2236 | /* | |
2237 | * If we tried hard to get a page but failed, set bit so that | |
2238 | * subsequent attempts will not try as hard until there is an | |
2239 | * overall state change. | |
2240 | */ | |
2241 | if (node_alloc_noretry && !page && alloc_try_hard) | |
2242 | node_set(nid, *node_alloc_noretry); | |
2243 | ||
19fc1a7e SK |
2244 | if (!page) { |
2245 | __count_vm_event(HTLB_BUDDY_PGALLOC_FAIL); | |
2246 | return NULL; | |
2247 | } | |
2248 | ||
2249 | __count_vm_event(HTLB_BUDDY_PGALLOC); | |
2250 | return page_folio(page); | |
63b4613c NA |
2251 | } |
2252 | ||
d67e32f2 MK |
2253 | static struct folio *__alloc_fresh_hugetlb_folio(struct hstate *h, |
2254 | gfp_t gfp_mask, int nid, nodemask_t *nmask, | |
2255 | nodemask_t *node_alloc_noretry) | |
0c397dae | 2256 | { |
7f325a8d | 2257 | struct folio *folio; |
7118fc29 | 2258 | bool retry = false; |
0c397dae | 2259 | |
7118fc29 | 2260 | retry: |
0c397dae | 2261 | if (hstate_is_gigantic(h)) |
19fc1a7e | 2262 | folio = alloc_gigantic_folio(h, gfp_mask, nid, nmask); |
0c397dae | 2263 | else |
19fc1a7e | 2264 | folio = alloc_buddy_hugetlb_folio(h, gfp_mask, |
f60858f9 | 2265 | nid, nmask, node_alloc_noretry); |
19fc1a7e | 2266 | if (!folio) |
0c397dae | 2267 | return NULL; |
d67e32f2 | 2268 | |
7118fc29 | 2269 | if (hstate_is_gigantic(h)) { |
d1c60955 | 2270 | if (!prep_compound_gigantic_folio(folio, huge_page_order(h))) { |
7118fc29 MK |
2271 | /* |
2272 | * Rare failure to convert pages to compound page. | |
2273 | * Free pages and try again - ONCE! | |
2274 | */ | |
7f325a8d | 2275 | free_gigantic_folio(folio, huge_page_order(h)); |
7118fc29 MK |
2276 | if (!retry) { |
2277 | retry = true; | |
2278 | goto retry; | |
2279 | } | |
7118fc29 MK |
2280 | return NULL; |
2281 | } | |
2282 | } | |
0c397dae | 2283 | |
19fc1a7e | 2284 | return folio; |
0c397dae MH |
2285 | } |
2286 | ||
d67e32f2 MK |
2287 | static struct folio *only_alloc_fresh_hugetlb_folio(struct hstate *h, |
2288 | gfp_t gfp_mask, int nid, nodemask_t *nmask, | |
2289 | nodemask_t *node_alloc_noretry) | |
2290 | { | |
2291 | struct folio *folio; | |
2292 | ||
2293 | folio = __alloc_fresh_hugetlb_folio(h, gfp_mask, nid, nmask, | |
2294 | node_alloc_noretry); | |
2295 | if (folio) | |
2296 | init_new_hugetlb_folio(h, folio); | |
2297 | return folio; | |
2298 | } | |
2299 | ||
af0fb9df | 2300 | /* |
d67e32f2 MK |
2301 | * Common helper to allocate a fresh hugetlb page. All specific allocators |
2302 | * should use this function to get new hugetlb pages | |
2303 | * | |
2304 | * Note that returned page is 'frozen': ref count of head page and all tail | |
2305 | * pages is zero. | |
af0fb9df | 2306 | */ |
d67e32f2 MK |
2307 | static struct folio *alloc_fresh_hugetlb_folio(struct hstate *h, |
2308 | gfp_t gfp_mask, int nid, nodemask_t *nmask, | |
2309 | nodemask_t *node_alloc_noretry) | |
b2261026 | 2310 | { |
19fc1a7e | 2311 | struct folio *folio; |
d67e32f2 MK |
2312 | |
2313 | folio = __alloc_fresh_hugetlb_folio(h, gfp_mask, nid, nmask, | |
2314 | node_alloc_noretry); | |
2315 | if (!folio) | |
2316 | return NULL; | |
2317 | ||
2318 | prep_new_hugetlb_folio(h, folio, folio_nid(folio)); | |
2319 | return folio; | |
2320 | } | |
2321 | ||
2322 | static void prep_and_add_allocated_folios(struct hstate *h, | |
2323 | struct list_head *folio_list) | |
2324 | { | |
2325 | unsigned long flags; | |
2326 | struct folio *folio, *tmp_f; | |
2327 | ||
79359d6d MK |
2328 | /* Send list for bulk vmemmap optimization processing */ |
2329 | hugetlb_vmemmap_optimize_folios(h, folio_list); | |
2330 | ||
d67e32f2 MK |
2331 | /* Add all new pool pages to free lists in one lock cycle */ |
2332 | spin_lock_irqsave(&hugetlb_lock, flags); | |
2333 | list_for_each_entry_safe(folio, tmp_f, folio_list, lru) { | |
2334 | __prep_account_new_huge_page(h, folio_nid(folio)); | |
2335 | enqueue_hugetlb_folio(h, folio); | |
2336 | } | |
2337 | spin_unlock_irqrestore(&hugetlb_lock, flags); | |
2338 | } | |
2339 | ||
2340 | /* | |
2341 | * Allocates a fresh hugetlb page in a node interleaved manner. The page | |
2342 | * will later be added to the appropriate hugetlb pool. | |
2343 | */ | |
2344 | static struct folio *alloc_pool_huge_folio(struct hstate *h, | |
2345 | nodemask_t *nodes_allowed, | |
2346 | nodemask_t *node_alloc_noretry) | |
2347 | { | |
af0fb9df | 2348 | gfp_t gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE; |
d67e32f2 | 2349 | int nr_nodes, node; |
b2261026 JK |
2350 | |
2351 | for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) { | |
d67e32f2 MK |
2352 | struct folio *folio; |
2353 | ||
2354 | folio = only_alloc_fresh_hugetlb_folio(h, gfp_mask, node, | |
19fc1a7e | 2355 | nodes_allowed, node_alloc_noretry); |
d67e32f2 MK |
2356 | if (folio) |
2357 | return folio; | |
b2261026 JK |
2358 | } |
2359 | ||
d67e32f2 | 2360 | return NULL; |
b2261026 JK |
2361 | } |
2362 | ||
e8c5c824 | 2363 | /* |
10c6ec49 MK |
2364 | * Remove huge page from pool from next node to free. Attempt to keep |
2365 | * persistent huge pages more or less balanced over allowed nodes. | |
2366 | * This routine only 'removes' the hugetlb page. The caller must make | |
2367 | * an additional call to free the page to low level allocators. | |
e8c5c824 LS |
2368 | * Called with hugetlb_lock locked. |
2369 | */ | |
d5b43e96 MWO |
2370 | static struct folio *remove_pool_hugetlb_folio(struct hstate *h, |
2371 | nodemask_t *nodes_allowed, bool acct_surplus) | |
e8c5c824 | 2372 | { |
b2261026 | 2373 | int nr_nodes, node; |
04bbfd84 | 2374 | struct folio *folio = NULL; |
e8c5c824 | 2375 | |
9487ca60 | 2376 | lockdep_assert_held(&hugetlb_lock); |
b2261026 | 2377 | for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { |
685f3457 LS |
2378 | /* |
2379 | * If we're returning unused surplus pages, only examine | |
2380 | * nodes with surplus pages. | |
2381 | */ | |
b2261026 JK |
2382 | if ((!acct_surplus || h->surplus_huge_pages_node[node]) && |
2383 | !list_empty(&h->hugepage_freelists[node])) { | |
04bbfd84 MWO |
2384 | folio = list_entry(h->hugepage_freelists[node].next, |
2385 | struct folio, lru); | |
cfd5082b | 2386 | remove_hugetlb_folio(h, folio, acct_surplus); |
9a76db09 | 2387 | break; |
e8c5c824 | 2388 | } |
b2261026 | 2389 | } |
e8c5c824 | 2390 | |
d5b43e96 | 2391 | return folio; |
e8c5c824 LS |
2392 | } |
2393 | ||
c8721bbb NH |
2394 | /* |
2395 | * Dissolve a given free hugepage into free buddy pages. This function does | |
faf53def NH |
2396 | * nothing for in-use hugepages and non-hugepages. |
2397 | * This function returns values like below: | |
2398 | * | |
ad2fa371 MS |
2399 | * -ENOMEM: failed to allocate vmemmap pages to free the freed hugepages |
2400 | * when the system is under memory pressure and the feature of | |
2401 | * freeing unused vmemmap pages associated with each hugetlb page | |
2402 | * is enabled. | |
2403 | * -EBUSY: failed to dissolved free hugepages or the hugepage is in-use | |
2404 | * (allocated or reserved.) | |
2405 | * 0: successfully dissolved free hugepages or the page is not a | |
2406 | * hugepage (considered as already dissolved) | |
c8721bbb | 2407 | */ |
c3114a84 | 2408 | int dissolve_free_huge_page(struct page *page) |
c8721bbb | 2409 | { |
6bc9b564 | 2410 | int rc = -EBUSY; |
1a7cdab5 | 2411 | struct folio *folio = page_folio(page); |
082d5b6b | 2412 | |
7ffddd49 | 2413 | retry: |
faf53def | 2414 | /* Not to disrupt normal path by vainly holding hugetlb_lock */ |
1a7cdab5 | 2415 | if (!folio_test_hugetlb(folio)) |
faf53def NH |
2416 | return 0; |
2417 | ||
db71ef79 | 2418 | spin_lock_irq(&hugetlb_lock); |
1a7cdab5 | 2419 | if (!folio_test_hugetlb(folio)) { |
faf53def NH |
2420 | rc = 0; |
2421 | goto out; | |
2422 | } | |
2423 | ||
1a7cdab5 SK |
2424 | if (!folio_ref_count(folio)) { |
2425 | struct hstate *h = folio_hstate(folio); | |
8346d69d | 2426 | if (!available_huge_pages(h)) |
082d5b6b | 2427 | goto out; |
7ffddd49 MS |
2428 | |
2429 | /* | |
2430 | * We should make sure that the page is already on the free list | |
2431 | * when it is dissolved. | |
2432 | */ | |
1a7cdab5 | 2433 | if (unlikely(!folio_test_hugetlb_freed(folio))) { |
db71ef79 | 2434 | spin_unlock_irq(&hugetlb_lock); |
7ffddd49 MS |
2435 | cond_resched(); |
2436 | ||
2437 | /* | |
2438 | * Theoretically, we should return -EBUSY when we | |
2439 | * encounter this race. In fact, we have a chance | |
2440 | * to successfully dissolve the page if we do a | |
2441 | * retry. Because the race window is quite small. | |
2442 | * If we seize this opportunity, it is an optimization | |
2443 | * for increasing the success rate of dissolving page. | |
2444 | */ | |
2445 | goto retry; | |
2446 | } | |
2447 | ||
cfd5082b | 2448 | remove_hugetlb_folio(h, folio, false); |
c1470b33 | 2449 | h->max_huge_pages--; |
db71ef79 | 2450 | spin_unlock_irq(&hugetlb_lock); |
ad2fa371 MS |
2451 | |
2452 | /* | |
d6ef19e2 SK |
2453 | * Normally update_and_free_hugtlb_folio will allocate required vmemmmap |
2454 | * before freeing the page. update_and_free_hugtlb_folio will fail to | |
ad2fa371 MS |
2455 | * free the page if it can not allocate required vmemmap. We |
2456 | * need to adjust max_huge_pages if the page is not freed. | |
2457 | * Attempt to allocate vmemmmap here so that we can take | |
2458 | * appropriate action on failure. | |
30a89adf MK |
2459 | * |
2460 | * The folio_test_hugetlb check here is because | |
2461 | * remove_hugetlb_folio will clear hugetlb folio flag for | |
2462 | * non-vmemmap optimized hugetlb folios. | |
ad2fa371 | 2463 | */ |
30a89adf | 2464 | if (folio_test_hugetlb(folio)) { |
c5ad3233 | 2465 | rc = hugetlb_vmemmap_restore_folio(h, folio); |
30a89adf MK |
2466 | if (rc) { |
2467 | spin_lock_irq(&hugetlb_lock); | |
2468 | add_hugetlb_folio(h, folio, false); | |
2469 | h->max_huge_pages++; | |
2470 | goto out; | |
2471 | } | |
2472 | } else | |
2473 | rc = 0; | |
ad2fa371 | 2474 | |
30a89adf | 2475 | update_and_free_hugetlb_folio(h, folio, false); |
ad2fa371 | 2476 | return rc; |
c8721bbb | 2477 | } |
082d5b6b | 2478 | out: |
db71ef79 | 2479 | spin_unlock_irq(&hugetlb_lock); |
082d5b6b | 2480 | return rc; |
c8721bbb NH |
2481 | } |
2482 | ||
2483 | /* | |
2484 | * Dissolve free hugepages in a given pfn range. Used by memory hotplug to | |
2485 | * make specified memory blocks removable from the system. | |
2247bb33 GS |
2486 | * Note that this will dissolve a free gigantic hugepage completely, if any |
2487 | * part of it lies within the given range. | |
082d5b6b GS |
2488 | * Also note that if dissolve_free_huge_page() returns with an error, all |
2489 | * free hugepages that were dissolved before that error are lost. | |
c8721bbb | 2490 | */ |
082d5b6b | 2491 | int dissolve_free_huge_pages(unsigned long start_pfn, unsigned long end_pfn) |
c8721bbb | 2492 | { |
c8721bbb | 2493 | unsigned long pfn; |
eb03aa00 | 2494 | struct page *page; |
082d5b6b | 2495 | int rc = 0; |
dc2628f3 MS |
2496 | unsigned int order; |
2497 | struct hstate *h; | |
c8721bbb | 2498 | |
d0177639 | 2499 | if (!hugepages_supported()) |
082d5b6b | 2500 | return rc; |
d0177639 | 2501 | |
dc2628f3 MS |
2502 | order = huge_page_order(&default_hstate); |
2503 | for_each_hstate(h) | |
2504 | order = min(order, huge_page_order(h)); | |
2505 | ||
2506 | for (pfn = start_pfn; pfn < end_pfn; pfn += 1 << order) { | |
eb03aa00 | 2507 | page = pfn_to_page(pfn); |
faf53def NH |
2508 | rc = dissolve_free_huge_page(page); |
2509 | if (rc) | |
2510 | break; | |
eb03aa00 | 2511 | } |
082d5b6b GS |
2512 | |
2513 | return rc; | |
c8721bbb NH |
2514 | } |
2515 | ||
ab5ac90a MH |
2516 | /* |
2517 | * Allocates a fresh surplus page from the page allocator. | |
2518 | */ | |
3a740e8b SK |
2519 | static struct folio *alloc_surplus_hugetlb_folio(struct hstate *h, |
2520 | gfp_t gfp_mask, int nid, nodemask_t *nmask) | |
7893d1d5 | 2521 | { |
19fc1a7e | 2522 | struct folio *folio = NULL; |
7893d1d5 | 2523 | |
bae7f4ae | 2524 | if (hstate_is_gigantic(h)) |
aa888a74 AK |
2525 | return NULL; |
2526 | ||
db71ef79 | 2527 | spin_lock_irq(&hugetlb_lock); |
9980d744 MH |
2528 | if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages) |
2529 | goto out_unlock; | |
db71ef79 | 2530 | spin_unlock_irq(&hugetlb_lock); |
d1c3fb1f | 2531 | |
19fc1a7e SK |
2532 | folio = alloc_fresh_hugetlb_folio(h, gfp_mask, nid, nmask, NULL); |
2533 | if (!folio) | |
0c397dae | 2534 | return NULL; |
d1c3fb1f | 2535 | |
db71ef79 | 2536 | spin_lock_irq(&hugetlb_lock); |
9980d744 MH |
2537 | /* |
2538 | * We could have raced with the pool size change. | |
2539 | * Double check that and simply deallocate the new page | |
2540 | * if we would end up overcommiting the surpluses. Abuse | |
454a00c4 | 2541 | * temporary page to workaround the nasty free_huge_folio |
9980d744 MH |
2542 | * codeflow |
2543 | */ | |
2544 | if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages) { | |
19fc1a7e | 2545 | folio_set_hugetlb_temporary(folio); |
db71ef79 | 2546 | spin_unlock_irq(&hugetlb_lock); |
454a00c4 | 2547 | free_huge_folio(folio); |
2bf753e6 | 2548 | return NULL; |
7893d1d5 | 2549 | } |
9980d744 | 2550 | |
b65a4eda | 2551 | h->surplus_huge_pages++; |
19fc1a7e | 2552 | h->surplus_huge_pages_node[folio_nid(folio)]++; |
b65a4eda | 2553 | |
9980d744 | 2554 | out_unlock: |
db71ef79 | 2555 | spin_unlock_irq(&hugetlb_lock); |
7893d1d5 | 2556 | |
3a740e8b | 2557 | return folio; |
7893d1d5 AL |
2558 | } |
2559 | ||
e37d3e83 | 2560 | static struct folio *alloc_migrate_hugetlb_folio(struct hstate *h, gfp_t gfp_mask, |
9a4e9f3b | 2561 | int nid, nodemask_t *nmask) |
ab5ac90a | 2562 | { |
19fc1a7e | 2563 | struct folio *folio; |
ab5ac90a MH |
2564 | |
2565 | if (hstate_is_gigantic(h)) | |
2566 | return NULL; | |
2567 | ||
19fc1a7e SK |
2568 | folio = alloc_fresh_hugetlb_folio(h, gfp_mask, nid, nmask, NULL); |
2569 | if (!folio) | |
ab5ac90a MH |
2570 | return NULL; |
2571 | ||
2b21624f | 2572 | /* fresh huge pages are frozen */ |
19fc1a7e | 2573 | folio_ref_unfreeze(folio, 1); |
ab5ac90a MH |
2574 | /* |
2575 | * We do not account these pages as surplus because they are only | |
2576 | * temporary and will be released properly on the last reference | |
2577 | */ | |
19fc1a7e | 2578 | folio_set_hugetlb_temporary(folio); |
ab5ac90a | 2579 | |
e37d3e83 | 2580 | return folio; |
ab5ac90a MH |
2581 | } |
2582 | ||
099730d6 DH |
2583 | /* |
2584 | * Use the VMA's mpolicy to allocate a huge page from the buddy. | |
2585 | */ | |
e0ec90ee | 2586 | static |
ff7d853b | 2587 | struct folio *alloc_buddy_hugetlb_folio_with_mpol(struct hstate *h, |
099730d6 DH |
2588 | struct vm_area_struct *vma, unsigned long addr) |
2589 | { | |
3a740e8b | 2590 | struct folio *folio = NULL; |
aaf14e40 MH |
2591 | struct mempolicy *mpol; |
2592 | gfp_t gfp_mask = htlb_alloc_mask(h); | |
2593 | int nid; | |
2594 | nodemask_t *nodemask; | |
2595 | ||
2596 | nid = huge_node(vma, addr, gfp_mask, &mpol, &nodemask); | |
cfcaa66f BW |
2597 | if (mpol_is_preferred_many(mpol)) { |
2598 | gfp_t gfp = gfp_mask | __GFP_NOWARN; | |
2599 | ||
2600 | gfp &= ~(__GFP_DIRECT_RECLAIM | __GFP_NOFAIL); | |
3a740e8b | 2601 | folio = alloc_surplus_hugetlb_folio(h, gfp, nid, nodemask); |
aaf14e40 | 2602 | |
cfcaa66f BW |
2603 | /* Fallback to all nodes if page==NULL */ |
2604 | nodemask = NULL; | |
2605 | } | |
2606 | ||
3a740e8b SK |
2607 | if (!folio) |
2608 | folio = alloc_surplus_hugetlb_folio(h, gfp_mask, nid, nodemask); | |
cfcaa66f | 2609 | mpol_cond_put(mpol); |
ff7d853b | 2610 | return folio; |
099730d6 DH |
2611 | } |
2612 | ||
e37d3e83 SK |
2613 | /* folio migration callback function */ |
2614 | struct folio *alloc_hugetlb_folio_nodemask(struct hstate *h, int preferred_nid, | |
d92bbc27 | 2615 | nodemask_t *nmask, gfp_t gfp_mask) |
4db9b2ef | 2616 | { |
db71ef79 | 2617 | spin_lock_irq(&hugetlb_lock); |
8346d69d | 2618 | if (available_huge_pages(h)) { |
a36f1e90 | 2619 | struct folio *folio; |
3e59fcb0 | 2620 | |
a36f1e90 SK |
2621 | folio = dequeue_hugetlb_folio_nodemask(h, gfp_mask, |
2622 | preferred_nid, nmask); | |
2623 | if (folio) { | |
db71ef79 | 2624 | spin_unlock_irq(&hugetlb_lock); |
e37d3e83 | 2625 | return folio; |
4db9b2ef MH |
2626 | } |
2627 | } | |
db71ef79 | 2628 | spin_unlock_irq(&hugetlb_lock); |
4db9b2ef | 2629 | |
e37d3e83 | 2630 | return alloc_migrate_hugetlb_folio(h, gfp_mask, preferred_nid, nmask); |
4db9b2ef MH |
2631 | } |
2632 | ||
e4e574b7 | 2633 | /* |
25985edc | 2634 | * Increase the hugetlb pool such that it can accommodate a reservation |
e4e574b7 AL |
2635 | * of size 'delta'. |
2636 | */ | |
0a4f3d1b | 2637 | static int gather_surplus_pages(struct hstate *h, long delta) |
1b2a1e7b | 2638 | __must_hold(&hugetlb_lock) |
e4e574b7 | 2639 | { |
34665341 | 2640 | LIST_HEAD(surplus_list); |
454a00c4 | 2641 | struct folio *folio, *tmp; |
0a4f3d1b LX |
2642 | int ret; |
2643 | long i; | |
2644 | long needed, allocated; | |
28073b02 | 2645 | bool alloc_ok = true; |
e4e574b7 | 2646 | |
9487ca60 | 2647 | lockdep_assert_held(&hugetlb_lock); |
a5516438 | 2648 | needed = (h->resv_huge_pages + delta) - h->free_huge_pages; |
ac09b3a1 | 2649 | if (needed <= 0) { |
a5516438 | 2650 | h->resv_huge_pages += delta; |
e4e574b7 | 2651 | return 0; |
ac09b3a1 | 2652 | } |
e4e574b7 AL |
2653 | |
2654 | allocated = 0; | |
e4e574b7 AL |
2655 | |
2656 | ret = -ENOMEM; | |
2657 | retry: | |
db71ef79 | 2658 | spin_unlock_irq(&hugetlb_lock); |
e4e574b7 | 2659 | for (i = 0; i < needed; i++) { |
3a740e8b | 2660 | folio = alloc_surplus_hugetlb_folio(h, htlb_alloc_mask(h), |
2b21624f | 2661 | NUMA_NO_NODE, NULL); |
3a740e8b | 2662 | if (!folio) { |
28073b02 HD |
2663 | alloc_ok = false; |
2664 | break; | |
2665 | } | |
3a740e8b | 2666 | list_add(&folio->lru, &surplus_list); |
69ed779a | 2667 | cond_resched(); |
e4e574b7 | 2668 | } |
28073b02 | 2669 | allocated += i; |
e4e574b7 AL |
2670 | |
2671 | /* | |
2672 | * After retaking hugetlb_lock, we need to recalculate 'needed' | |
2673 | * because either resv_huge_pages or free_huge_pages may have changed. | |
2674 | */ | |
db71ef79 | 2675 | spin_lock_irq(&hugetlb_lock); |
a5516438 AK |
2676 | needed = (h->resv_huge_pages + delta) - |
2677 | (h->free_huge_pages + allocated); | |
28073b02 HD |
2678 | if (needed > 0) { |
2679 | if (alloc_ok) | |
2680 | goto retry; | |
2681 | /* | |
2682 | * We were not able to allocate enough pages to | |
2683 | * satisfy the entire reservation so we free what | |
2684 | * we've allocated so far. | |
2685 | */ | |
2686 | goto free; | |
2687 | } | |
e4e574b7 AL |
2688 | /* |
2689 | * The surplus_list now contains _at_least_ the number of extra pages | |
25985edc | 2690 | * needed to accommodate the reservation. Add the appropriate number |
e4e574b7 | 2691 | * of pages to the hugetlb pool and free the extras back to the buddy |
ac09b3a1 AL |
2692 | * allocator. Commit the entire reservation here to prevent another |
2693 | * process from stealing the pages as they are added to the pool but | |
2694 | * before they are reserved. | |
e4e574b7 AL |
2695 | */ |
2696 | needed += allocated; | |
a5516438 | 2697 | h->resv_huge_pages += delta; |
e4e574b7 | 2698 | ret = 0; |
a9869b83 | 2699 | |
19fc3f0a | 2700 | /* Free the needed pages to the hugetlb pool */ |
454a00c4 | 2701 | list_for_each_entry_safe(folio, tmp, &surplus_list, lru) { |
19fc3f0a AL |
2702 | if ((--needed) < 0) |
2703 | break; | |
b65a4eda | 2704 | /* Add the page to the hugetlb allocator */ |
454a00c4 | 2705 | enqueue_hugetlb_folio(h, folio); |
19fc3f0a | 2706 | } |
28073b02 | 2707 | free: |
db71ef79 | 2708 | spin_unlock_irq(&hugetlb_lock); |
19fc3f0a | 2709 | |
b65a4eda MK |
2710 | /* |
2711 | * Free unnecessary surplus pages to the buddy allocator. | |
454a00c4 | 2712 | * Pages have no ref count, call free_huge_folio directly. |
b65a4eda | 2713 | */ |
454a00c4 MWO |
2714 | list_for_each_entry_safe(folio, tmp, &surplus_list, lru) |
2715 | free_huge_folio(folio); | |
db71ef79 | 2716 | spin_lock_irq(&hugetlb_lock); |
e4e574b7 AL |
2717 | |
2718 | return ret; | |
2719 | } | |
2720 | ||
2721 | /* | |
e5bbc8a6 MK |
2722 | * This routine has two main purposes: |
2723 | * 1) Decrement the reservation count (resv_huge_pages) by the value passed | |
2724 | * in unused_resv_pages. This corresponds to the prior adjustments made | |
2725 | * to the associated reservation map. | |
2726 | * 2) Free any unused surplus pages that may have been allocated to satisfy | |
2727 | * the reservation. As many as unused_resv_pages may be freed. | |
e4e574b7 | 2728 | */ |
a5516438 AK |
2729 | static void return_unused_surplus_pages(struct hstate *h, |
2730 | unsigned long unused_resv_pages) | |
e4e574b7 | 2731 | { |
e4e574b7 | 2732 | unsigned long nr_pages; |
10c6ec49 MK |
2733 | LIST_HEAD(page_list); |
2734 | ||
9487ca60 | 2735 | lockdep_assert_held(&hugetlb_lock); |
10c6ec49 MK |
2736 | /* Uncommit the reservation */ |
2737 | h->resv_huge_pages -= unused_resv_pages; | |
e4e574b7 | 2738 | |
c0531714 | 2739 | if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) |
e5bbc8a6 | 2740 | goto out; |
aa888a74 | 2741 | |
e5bbc8a6 MK |
2742 | /* |
2743 | * Part (or even all) of the reservation could have been backed | |
2744 | * by pre-allocated pages. Only free surplus pages. | |
2745 | */ | |
a5516438 | 2746 | nr_pages = min(unused_resv_pages, h->surplus_huge_pages); |
e4e574b7 | 2747 | |
685f3457 LS |
2748 | /* |
2749 | * We want to release as many surplus pages as possible, spread | |
9b5e5d0f LS |
2750 | * evenly across all nodes with memory. Iterate across these nodes |
2751 | * until we can no longer free unreserved surplus pages. This occurs | |
2752 | * when the nodes with surplus pages have no free pages. | |
d5b43e96 | 2753 | * remove_pool_hugetlb_folio() will balance the freed pages across the |
9b5e5d0f | 2754 | * on-line nodes with memory and will handle the hstate accounting. |
685f3457 LS |
2755 | */ |
2756 | while (nr_pages--) { | |
d5b43e96 MWO |
2757 | struct folio *folio; |
2758 | ||
2759 | folio = remove_pool_hugetlb_folio(h, &node_states[N_MEMORY], 1); | |
2760 | if (!folio) | |
e5bbc8a6 | 2761 | goto out; |
10c6ec49 | 2762 | |
d5b43e96 | 2763 | list_add(&folio->lru, &page_list); |
e4e574b7 | 2764 | } |
e5bbc8a6 MK |
2765 | |
2766 | out: | |
db71ef79 | 2767 | spin_unlock_irq(&hugetlb_lock); |
10c6ec49 | 2768 | update_and_free_pages_bulk(h, &page_list); |
db71ef79 | 2769 | spin_lock_irq(&hugetlb_lock); |
e4e574b7 AL |
2770 | } |
2771 | ||
5e911373 | 2772 | |
c37f9fb1 | 2773 | /* |
feba16e2 | 2774 | * vma_needs_reservation, vma_commit_reservation and vma_end_reservation |
5e911373 | 2775 | * are used by the huge page allocation routines to manage reservations. |
cf3ad20b MK |
2776 | * |
2777 | * vma_needs_reservation is called to determine if the huge page at addr | |
2778 | * within the vma has an associated reservation. If a reservation is | |
2779 | * needed, the value 1 is returned. The caller is then responsible for | |
2780 | * managing the global reservation and subpool usage counts. After | |
2781 | * the huge page has been allocated, vma_commit_reservation is called | |
feba16e2 MK |
2782 | * to add the page to the reservation map. If the page allocation fails, |
2783 | * the reservation must be ended instead of committed. vma_end_reservation | |
2784 | * is called in such cases. | |
cf3ad20b MK |
2785 | * |
2786 | * In the normal case, vma_commit_reservation returns the same value | |
2787 | * as the preceding vma_needs_reservation call. The only time this | |
2788 | * is not the case is if a reserve map was changed between calls. It | |
2789 | * is the responsibility of the caller to notice the difference and | |
2790 | * take appropriate action. | |
96b96a96 MK |
2791 | * |
2792 | * vma_add_reservation is used in error paths where a reservation must | |
2793 | * be restored when a newly allocated huge page must be freed. It is | |
2794 | * to be called after calling vma_needs_reservation to determine if a | |
2795 | * reservation exists. | |
846be085 MK |
2796 | * |
2797 | * vma_del_reservation is used in error paths where an entry in the reserve | |
2798 | * map was created during huge page allocation and must be removed. It is to | |
2799 | * be called after calling vma_needs_reservation to determine if a reservation | |
2800 | * exists. | |
c37f9fb1 | 2801 | */ |
5e911373 MK |
2802 | enum vma_resv_mode { |
2803 | VMA_NEEDS_RESV, | |
2804 | VMA_COMMIT_RESV, | |
feba16e2 | 2805 | VMA_END_RESV, |
96b96a96 | 2806 | VMA_ADD_RESV, |
846be085 | 2807 | VMA_DEL_RESV, |
5e911373 | 2808 | }; |
cf3ad20b MK |
2809 | static long __vma_reservation_common(struct hstate *h, |
2810 | struct vm_area_struct *vma, unsigned long addr, | |
5e911373 | 2811 | enum vma_resv_mode mode) |
c37f9fb1 | 2812 | { |
4e35f483 JK |
2813 | struct resv_map *resv; |
2814 | pgoff_t idx; | |
cf3ad20b | 2815 | long ret; |
0db9d74e | 2816 | long dummy_out_regions_needed; |
c37f9fb1 | 2817 | |
4e35f483 JK |
2818 | resv = vma_resv_map(vma); |
2819 | if (!resv) | |
84afd99b | 2820 | return 1; |
c37f9fb1 | 2821 | |
4e35f483 | 2822 | idx = vma_hugecache_offset(h, vma, addr); |
5e911373 MK |
2823 | switch (mode) { |
2824 | case VMA_NEEDS_RESV: | |
0db9d74e MA |
2825 | ret = region_chg(resv, idx, idx + 1, &dummy_out_regions_needed); |
2826 | /* We assume that vma_reservation_* routines always operate on | |
2827 | * 1 page, and that adding to resv map a 1 page entry can only | |
2828 | * ever require 1 region. | |
2829 | */ | |
2830 | VM_BUG_ON(dummy_out_regions_needed != 1); | |
5e911373 MK |
2831 | break; |
2832 | case VMA_COMMIT_RESV: | |
075a61d0 | 2833 | ret = region_add(resv, idx, idx + 1, 1, NULL, NULL); |
0db9d74e MA |
2834 | /* region_add calls of range 1 should never fail. */ |
2835 | VM_BUG_ON(ret < 0); | |
5e911373 | 2836 | break; |
feba16e2 | 2837 | case VMA_END_RESV: |
0db9d74e | 2838 | region_abort(resv, idx, idx + 1, 1); |
5e911373 MK |
2839 | ret = 0; |
2840 | break; | |
96b96a96 | 2841 | case VMA_ADD_RESV: |
0db9d74e | 2842 | if (vma->vm_flags & VM_MAYSHARE) { |
075a61d0 | 2843 | ret = region_add(resv, idx, idx + 1, 1, NULL, NULL); |
0db9d74e MA |
2844 | /* region_add calls of range 1 should never fail. */ |
2845 | VM_BUG_ON(ret < 0); | |
2846 | } else { | |
2847 | region_abort(resv, idx, idx + 1, 1); | |
96b96a96 MK |
2848 | ret = region_del(resv, idx, idx + 1); |
2849 | } | |
2850 | break; | |
846be085 MK |
2851 | case VMA_DEL_RESV: |
2852 | if (vma->vm_flags & VM_MAYSHARE) { | |
2853 | region_abort(resv, idx, idx + 1, 1); | |
2854 | ret = region_del(resv, idx, idx + 1); | |
2855 | } else { | |
2856 | ret = region_add(resv, idx, idx + 1, 1, NULL, NULL); | |
2857 | /* region_add calls of range 1 should never fail. */ | |
2858 | VM_BUG_ON(ret < 0); | |
2859 | } | |
2860 | break; | |
5e911373 MK |
2861 | default: |
2862 | BUG(); | |
2863 | } | |
84afd99b | 2864 | |
846be085 | 2865 | if (vma->vm_flags & VM_MAYSHARE || mode == VMA_DEL_RESV) |
cf3ad20b | 2866 | return ret; |
bf3d12b9 ML |
2867 | /* |
2868 | * We know private mapping must have HPAGE_RESV_OWNER set. | |
2869 | * | |
2870 | * In most cases, reserves always exist for private mappings. | |
2871 | * However, a file associated with mapping could have been | |
2872 | * hole punched or truncated after reserves were consumed. | |
2873 | * As subsequent fault on such a range will not use reserves. | |
2874 | * Subtle - The reserve map for private mappings has the | |
2875 | * opposite meaning than that of shared mappings. If NO | |
2876 | * entry is in the reserve map, it means a reservation exists. | |
2877 | * If an entry exists in the reserve map, it means the | |
2878 | * reservation has already been consumed. As a result, the | |
2879 | * return value of this routine is the opposite of the | |
2880 | * value returned from reserve map manipulation routines above. | |
2881 | */ | |
2882 | if (ret > 0) | |
2883 | return 0; | |
2884 | if (ret == 0) | |
2885 | return 1; | |
2886 | return ret; | |
c37f9fb1 | 2887 | } |
cf3ad20b MK |
2888 | |
2889 | static long vma_needs_reservation(struct hstate *h, | |
a5516438 | 2890 | struct vm_area_struct *vma, unsigned long addr) |
c37f9fb1 | 2891 | { |
5e911373 | 2892 | return __vma_reservation_common(h, vma, addr, VMA_NEEDS_RESV); |
cf3ad20b | 2893 | } |
84afd99b | 2894 | |
cf3ad20b MK |
2895 | static long vma_commit_reservation(struct hstate *h, |
2896 | struct vm_area_struct *vma, unsigned long addr) | |
2897 | { | |
5e911373 MK |
2898 | return __vma_reservation_common(h, vma, addr, VMA_COMMIT_RESV); |
2899 | } | |
2900 | ||
feba16e2 | 2901 | static void vma_end_reservation(struct hstate *h, |
5e911373 MK |
2902 | struct vm_area_struct *vma, unsigned long addr) |
2903 | { | |
feba16e2 | 2904 | (void)__vma_reservation_common(h, vma, addr, VMA_END_RESV); |
c37f9fb1 AW |
2905 | } |
2906 | ||
96b96a96 MK |
2907 | static long vma_add_reservation(struct hstate *h, |
2908 | struct vm_area_struct *vma, unsigned long addr) | |
2909 | { | |
2910 | return __vma_reservation_common(h, vma, addr, VMA_ADD_RESV); | |
2911 | } | |
2912 | ||
846be085 MK |
2913 | static long vma_del_reservation(struct hstate *h, |
2914 | struct vm_area_struct *vma, unsigned long addr) | |
2915 | { | |
2916 | return __vma_reservation_common(h, vma, addr, VMA_DEL_RESV); | |
2917 | } | |
2918 | ||
96b96a96 | 2919 | /* |
846be085 | 2920 | * This routine is called to restore reservation information on error paths. |
d0ce0e47 SK |
2921 | * It should ONLY be called for folios allocated via alloc_hugetlb_folio(), |
2922 | * and the hugetlb mutex should remain held when calling this routine. | |
846be085 MK |
2923 | * |
2924 | * It handles two specific cases: | |
d2d7bb44 SK |
2925 | * 1) A reservation was in place and the folio consumed the reservation. |
2926 | * hugetlb_restore_reserve is set in the folio. | |
2927 | * 2) No reservation was in place for the page, so hugetlb_restore_reserve is | |
d0ce0e47 | 2928 | * not set. However, alloc_hugetlb_folio always updates the reserve map. |
846be085 | 2929 | * |
454a00c4 MWO |
2930 | * In case 1, free_huge_folio later in the error path will increment the |
2931 | * global reserve count. But, free_huge_folio does not have enough context | |
846be085 MK |
2932 | * to adjust the reservation map. This case deals primarily with private |
2933 | * mappings. Adjust the reserve map here to be consistent with global | |
454a00c4 | 2934 | * reserve count adjustments to be made by free_huge_folio. Make sure the |
846be085 MK |
2935 | * reserve map indicates there is a reservation present. |
2936 | * | |
d0ce0e47 | 2937 | * In case 2, simply undo reserve map modifications done by alloc_hugetlb_folio. |
96b96a96 | 2938 | */ |
846be085 | 2939 | void restore_reserve_on_error(struct hstate *h, struct vm_area_struct *vma, |
d2d7bb44 | 2940 | unsigned long address, struct folio *folio) |
96b96a96 | 2941 | { |
846be085 | 2942 | long rc = vma_needs_reservation(h, vma, address); |
96b96a96 | 2943 | |
0ffdc38e | 2944 | if (folio_test_hugetlb_restore_reserve(folio)) { |
846be085 | 2945 | if (unlikely(rc < 0)) |
96b96a96 MK |
2946 | /* |
2947 | * Rare out of memory condition in reserve map | |
0ffdc38e SK |
2948 | * manipulation. Clear hugetlb_restore_reserve so |
2949 | * that global reserve count will not be incremented | |
454a00c4 | 2950 | * by free_huge_folio. This will make it appear |
0ffdc38e | 2951 | * as though the reservation for this folio was |
96b96a96 | 2952 | * consumed. This may prevent the task from |
0ffdc38e | 2953 | * faulting in the folio at a later time. This |
96b96a96 MK |
2954 | * is better than inconsistent global huge page |
2955 | * accounting of reserve counts. | |
2956 | */ | |
0ffdc38e | 2957 | folio_clear_hugetlb_restore_reserve(folio); |
846be085 MK |
2958 | else if (rc) |
2959 | (void)vma_add_reservation(h, vma, address); | |
2960 | else | |
2961 | vma_end_reservation(h, vma, address); | |
2962 | } else { | |
2963 | if (!rc) { | |
2964 | /* | |
2965 | * This indicates there is an entry in the reserve map | |
d0ce0e47 SK |
2966 | * not added by alloc_hugetlb_folio. We know it was added |
2967 | * before the alloc_hugetlb_folio call, otherwise | |
0ffdc38e | 2968 | * hugetlb_restore_reserve would be set on the folio. |
846be085 MK |
2969 | * Remove the entry so that a subsequent allocation |
2970 | * does not consume a reservation. | |
2971 | */ | |
2972 | rc = vma_del_reservation(h, vma, address); | |
2973 | if (rc < 0) | |
96b96a96 | 2974 | /* |
846be085 MK |
2975 | * VERY rare out of memory condition. Since |
2976 | * we can not delete the entry, set | |
0ffdc38e SK |
2977 | * hugetlb_restore_reserve so that the reserve |
2978 | * count will be incremented when the folio | |
846be085 MK |
2979 | * is freed. This reserve will be consumed |
2980 | * on a subsequent allocation. | |
96b96a96 | 2981 | */ |
0ffdc38e | 2982 | folio_set_hugetlb_restore_reserve(folio); |
846be085 MK |
2983 | } else if (rc < 0) { |
2984 | /* | |
2985 | * Rare out of memory condition from | |
2986 | * vma_needs_reservation call. Memory allocation is | |
2987 | * only attempted if a new entry is needed. Therefore, | |
2988 | * this implies there is not an entry in the | |
2989 | * reserve map. | |
2990 | * | |
2991 | * For shared mappings, no entry in the map indicates | |
2992 | * no reservation. We are done. | |
2993 | */ | |
2994 | if (!(vma->vm_flags & VM_MAYSHARE)) | |
2995 | /* | |
2996 | * For private mappings, no entry indicates | |
2997 | * a reservation is present. Since we can | |
0ffdc38e SK |
2998 | * not add an entry, set hugetlb_restore_reserve |
2999 | * on the folio so reserve count will be | |
846be085 MK |
3000 | * incremented when freed. This reserve will |
3001 | * be consumed on a subsequent allocation. | |
3002 | */ | |
0ffdc38e | 3003 | folio_set_hugetlb_restore_reserve(folio); |
96b96a96 | 3004 | } else |
846be085 MK |
3005 | /* |
3006 | * No reservation present, do nothing | |
3007 | */ | |
3008 | vma_end_reservation(h, vma, address); | |
96b96a96 MK |
3009 | } |
3010 | } | |
3011 | ||
369fa227 | 3012 | /* |
19fc1a7e SK |
3013 | * alloc_and_dissolve_hugetlb_folio - Allocate a new folio and dissolve |
3014 | * the old one | |
369fa227 | 3015 | * @h: struct hstate old page belongs to |
19fc1a7e | 3016 | * @old_folio: Old folio to dissolve |
ae37c7ff | 3017 | * @list: List to isolate the page in case we need to |
369fa227 OS |
3018 | * Returns 0 on success, otherwise negated error. |
3019 | */ | |
19fc1a7e SK |
3020 | static int alloc_and_dissolve_hugetlb_folio(struct hstate *h, |
3021 | struct folio *old_folio, struct list_head *list) | |
369fa227 OS |
3022 | { |
3023 | gfp_t gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE; | |
de656ed3 | 3024 | int nid = folio_nid(old_folio); |
de656ed3 | 3025 | struct folio *new_folio; |
369fa227 OS |
3026 | int ret = 0; |
3027 | ||
3028 | /* | |
19fc1a7e SK |
3029 | * Before dissolving the folio, we need to allocate a new one for the |
3030 | * pool to remain stable. Here, we allocate the folio and 'prep' it | |
f41f2ed4 MS |
3031 | * by doing everything but actually updating counters and adding to |
3032 | * the pool. This simplifies and let us do most of the processing | |
3033 | * under the lock. | |
369fa227 | 3034 | */ |
19fc1a7e SK |
3035 | new_folio = alloc_buddy_hugetlb_folio(h, gfp_mask, nid, NULL, NULL); |
3036 | if (!new_folio) | |
369fa227 | 3037 | return -ENOMEM; |
de656ed3 | 3038 | __prep_new_hugetlb_folio(h, new_folio); |
369fa227 OS |
3039 | |
3040 | retry: | |
3041 | spin_lock_irq(&hugetlb_lock); | |
de656ed3 | 3042 | if (!folio_test_hugetlb(old_folio)) { |
369fa227 | 3043 | /* |
19fc1a7e | 3044 | * Freed from under us. Drop new_folio too. |
369fa227 OS |
3045 | */ |
3046 | goto free_new; | |
de656ed3 | 3047 | } else if (folio_ref_count(old_folio)) { |
9747b9e9 BW |
3048 | bool isolated; |
3049 | ||
369fa227 | 3050 | /* |
19fc1a7e | 3051 | * Someone has grabbed the folio, try to isolate it here. |
ae37c7ff | 3052 | * Fail with -EBUSY if not possible. |
369fa227 | 3053 | */ |
ae37c7ff | 3054 | spin_unlock_irq(&hugetlb_lock); |
9747b9e9 BW |
3055 | isolated = isolate_hugetlb(old_folio, list); |
3056 | ret = isolated ? 0 : -EBUSY; | |
ae37c7ff | 3057 | spin_lock_irq(&hugetlb_lock); |
369fa227 | 3058 | goto free_new; |
de656ed3 | 3059 | } else if (!folio_test_hugetlb_freed(old_folio)) { |
369fa227 | 3060 | /* |
19fc1a7e | 3061 | * Folio's refcount is 0 but it has not been enqueued in the |
369fa227 OS |
3062 | * freelist yet. Race window is small, so we can succeed here if |
3063 | * we retry. | |
3064 | */ | |
3065 | spin_unlock_irq(&hugetlb_lock); | |
3066 | cond_resched(); | |
3067 | goto retry; | |
3068 | } else { | |
3069 | /* | |
19fc1a7e | 3070 | * Ok, old_folio is still a genuine free hugepage. Remove it from |
369fa227 OS |
3071 | * the freelist and decrease the counters. These will be |
3072 | * incremented again when calling __prep_account_new_huge_page() | |
240d67a8 SK |
3073 | * and enqueue_hugetlb_folio() for new_folio. The counters will |
3074 | * remain stable since this happens under the lock. | |
369fa227 | 3075 | */ |
cfd5082b | 3076 | remove_hugetlb_folio(h, old_folio, false); |
369fa227 OS |
3077 | |
3078 | /* | |
19fc1a7e | 3079 | * Ref count on new_folio is already zero as it was dropped |
b65a4eda | 3080 | * earlier. It can be directly added to the pool free list. |
369fa227 | 3081 | */ |
369fa227 | 3082 | __prep_account_new_huge_page(h, nid); |
240d67a8 | 3083 | enqueue_hugetlb_folio(h, new_folio); |
369fa227 OS |
3084 | |
3085 | /* | |
19fc1a7e | 3086 | * Folio has been replaced, we can safely free the old one. |
369fa227 OS |
3087 | */ |
3088 | spin_unlock_irq(&hugetlb_lock); | |
d6ef19e2 | 3089 | update_and_free_hugetlb_folio(h, old_folio, false); |
369fa227 OS |
3090 | } |
3091 | ||
3092 | return ret; | |
3093 | ||
3094 | free_new: | |
3095 | spin_unlock_irq(&hugetlb_lock); | |
19fc1a7e | 3096 | /* Folio has a zero ref count, but needs a ref to be freed */ |
de656ed3 | 3097 | folio_ref_unfreeze(new_folio, 1); |
d6ef19e2 | 3098 | update_and_free_hugetlb_folio(h, new_folio, false); |
369fa227 OS |
3099 | |
3100 | return ret; | |
3101 | } | |
3102 | ||
ae37c7ff | 3103 | int isolate_or_dissolve_huge_page(struct page *page, struct list_head *list) |
369fa227 OS |
3104 | { |
3105 | struct hstate *h; | |
d5e33bd8 | 3106 | struct folio *folio = page_folio(page); |
ae37c7ff | 3107 | int ret = -EBUSY; |
369fa227 OS |
3108 | |
3109 | /* | |
3110 | * The page might have been dissolved from under our feet, so make sure | |
3111 | * to carefully check the state under the lock. | |
3112 | * Return success when racing as if we dissolved the page ourselves. | |
3113 | */ | |
3114 | spin_lock_irq(&hugetlb_lock); | |
d5e33bd8 SK |
3115 | if (folio_test_hugetlb(folio)) { |
3116 | h = folio_hstate(folio); | |
369fa227 OS |
3117 | } else { |
3118 | spin_unlock_irq(&hugetlb_lock); | |
3119 | return 0; | |
3120 | } | |
3121 | spin_unlock_irq(&hugetlb_lock); | |
3122 | ||
3123 | /* | |
3124 | * Fence off gigantic pages as there is a cyclic dependency between | |
3125 | * alloc_contig_range and them. Return -ENOMEM as this has the effect | |
3126 | * of bailing out right away without further retrying. | |
3127 | */ | |
3128 | if (hstate_is_gigantic(h)) | |
3129 | return -ENOMEM; | |
3130 | ||
9747b9e9 | 3131 | if (folio_ref_count(folio) && isolate_hugetlb(folio, list)) |
ae37c7ff | 3132 | ret = 0; |
d5e33bd8 | 3133 | else if (!folio_ref_count(folio)) |
19fc1a7e | 3134 | ret = alloc_and_dissolve_hugetlb_folio(h, folio, list); |
ae37c7ff OS |
3135 | |
3136 | return ret; | |
369fa227 OS |
3137 | } |
3138 | ||
d0ce0e47 | 3139 | struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma, |
04f2cbe3 | 3140 | unsigned long addr, int avoid_reserve) |
1da177e4 | 3141 | { |
90481622 | 3142 | struct hugepage_subpool *spool = subpool_vma(vma); |
a5516438 | 3143 | struct hstate *h = hstate_vma(vma); |
d4ab0316 | 3144 | struct folio *folio; |
8cba9576 | 3145 | long map_chg, map_commit, nr_pages = pages_per_huge_page(h); |
d85f69b0 | 3146 | long gbl_chg; |
8cba9576 | 3147 | int memcg_charge_ret, ret, idx; |
d0ce0e47 | 3148 | struct hugetlb_cgroup *h_cg = NULL; |
8cba9576 | 3149 | struct mem_cgroup *memcg; |
08cf9faf | 3150 | bool deferred_reserve; |
8cba9576 NP |
3151 | gfp_t gfp = htlb_alloc_mask(h) | __GFP_RETRY_MAYFAIL; |
3152 | ||
3153 | memcg = get_mem_cgroup_from_current(); | |
3154 | memcg_charge_ret = mem_cgroup_hugetlb_try_charge(memcg, gfp, nr_pages); | |
3155 | if (memcg_charge_ret == -ENOMEM) { | |
3156 | mem_cgroup_put(memcg); | |
3157 | return ERR_PTR(-ENOMEM); | |
3158 | } | |
a1e78772 | 3159 | |
6d76dcf4 | 3160 | idx = hstate_index(h); |
a1e78772 | 3161 | /* |
d85f69b0 MK |
3162 | * Examine the region/reserve map to determine if the process |
3163 | * has a reservation for the page to be allocated. A return | |
3164 | * code of zero indicates a reservation exists (no change). | |
a1e78772 | 3165 | */ |
d85f69b0 | 3166 | map_chg = gbl_chg = vma_needs_reservation(h, vma, addr); |
8cba9576 NP |
3167 | if (map_chg < 0) { |
3168 | if (!memcg_charge_ret) | |
3169 | mem_cgroup_cancel_charge(memcg, nr_pages); | |
3170 | mem_cgroup_put(memcg); | |
76dcee75 | 3171 | return ERR_PTR(-ENOMEM); |
8cba9576 | 3172 | } |
d85f69b0 MK |
3173 | |
3174 | /* | |
3175 | * Processes that did not create the mapping will have no | |
3176 | * reserves as indicated by the region/reserve map. Check | |
3177 | * that the allocation will not exceed the subpool limit. | |
3178 | * Allocations for MAP_NORESERVE mappings also need to be | |
3179 | * checked against any subpool limit. | |
3180 | */ | |
3181 | if (map_chg || avoid_reserve) { | |
3182 | gbl_chg = hugepage_subpool_get_pages(spool, 1); | |
8cba9576 NP |
3183 | if (gbl_chg < 0) |
3184 | goto out_end_reservation; | |
1da177e4 | 3185 | |
d85f69b0 MK |
3186 | /* |
3187 | * Even though there was no reservation in the region/reserve | |
3188 | * map, there could be reservations associated with the | |
3189 | * subpool that can be used. This would be indicated if the | |
3190 | * return value of hugepage_subpool_get_pages() is zero. | |
3191 | * However, if avoid_reserve is specified we still avoid even | |
3192 | * the subpool reservations. | |
3193 | */ | |
3194 | if (avoid_reserve) | |
3195 | gbl_chg = 1; | |
3196 | } | |
3197 | ||
08cf9faf MA |
3198 | /* If this allocation is not consuming a reservation, charge it now. |
3199 | */ | |
6501fe5f | 3200 | deferred_reserve = map_chg || avoid_reserve; |
08cf9faf MA |
3201 | if (deferred_reserve) { |
3202 | ret = hugetlb_cgroup_charge_cgroup_rsvd( | |
3203 | idx, pages_per_huge_page(h), &h_cg); | |
3204 | if (ret) | |
3205 | goto out_subpool_put; | |
3206 | } | |
3207 | ||
6d76dcf4 | 3208 | ret = hugetlb_cgroup_charge_cgroup(idx, pages_per_huge_page(h), &h_cg); |
8f34af6f | 3209 | if (ret) |
08cf9faf | 3210 | goto out_uncharge_cgroup_reservation; |
8f34af6f | 3211 | |
db71ef79 | 3212 | spin_lock_irq(&hugetlb_lock); |
d85f69b0 MK |
3213 | /* |
3214 | * glb_chg is passed to indicate whether or not a page must be taken | |
3215 | * from the global free pool (global change). gbl_chg == 0 indicates | |
3216 | * a reservation exists for the allocation. | |
3217 | */ | |
ff7d853b SK |
3218 | folio = dequeue_hugetlb_folio_vma(h, vma, addr, avoid_reserve, gbl_chg); |
3219 | if (!folio) { | |
db71ef79 | 3220 | spin_unlock_irq(&hugetlb_lock); |
ff7d853b SK |
3221 | folio = alloc_buddy_hugetlb_folio_with_mpol(h, vma, addr); |
3222 | if (!folio) | |
8f34af6f | 3223 | goto out_uncharge_cgroup; |
12df140f | 3224 | spin_lock_irq(&hugetlb_lock); |
a88c7695 | 3225 | if (!avoid_reserve && vma_has_reserves(vma, gbl_chg)) { |
ff7d853b | 3226 | folio_set_hugetlb_restore_reserve(folio); |
a88c7695 NH |
3227 | h->resv_huge_pages--; |
3228 | } | |
ff7d853b SK |
3229 | list_add(&folio->lru, &h->hugepage_activelist); |
3230 | folio_ref_unfreeze(folio, 1); | |
81a6fcae | 3231 | /* Fall through */ |
68842c9b | 3232 | } |
ff7d853b SK |
3233 | |
3234 | hugetlb_cgroup_commit_charge(idx, pages_per_huge_page(h), h_cg, folio); | |
08cf9faf MA |
3235 | /* If allocation is not consuming a reservation, also store the |
3236 | * hugetlb_cgroup pointer on the page. | |
3237 | */ | |
3238 | if (deferred_reserve) { | |
3239 | hugetlb_cgroup_commit_charge_rsvd(idx, pages_per_huge_page(h), | |
ff7d853b | 3240 | h_cg, folio); |
08cf9faf MA |
3241 | } |
3242 | ||
db71ef79 | 3243 | spin_unlock_irq(&hugetlb_lock); |
348ea204 | 3244 | |
ff7d853b | 3245 | hugetlb_set_folio_subpool(folio, spool); |
90d8b7e6 | 3246 | |
d85f69b0 MK |
3247 | map_commit = vma_commit_reservation(h, vma, addr); |
3248 | if (unlikely(map_chg > map_commit)) { | |
33039678 MK |
3249 | /* |
3250 | * The page was added to the reservation map between | |
3251 | * vma_needs_reservation and vma_commit_reservation. | |
3252 | * This indicates a race with hugetlb_reserve_pages. | |
3253 | * Adjust for the subpool count incremented above AND | |
3254 | * in hugetlb_reserve_pages for the same page. Also, | |
3255 | * the reservation count added in hugetlb_reserve_pages | |
3256 | * no longer applies. | |
3257 | */ | |
3258 | long rsv_adjust; | |
3259 | ||
3260 | rsv_adjust = hugepage_subpool_put_pages(spool, 1); | |
3261 | hugetlb_acct_memory(h, -rsv_adjust); | |
79aa925b | 3262 | if (deferred_reserve) |
d4ab0316 SK |
3263 | hugetlb_cgroup_uncharge_folio_rsvd(hstate_index(h), |
3264 | pages_per_huge_page(h), folio); | |
33039678 | 3265 | } |
8cba9576 NP |
3266 | |
3267 | if (!memcg_charge_ret) | |
3268 | mem_cgroup_commit_charge(folio, memcg); | |
3269 | mem_cgroup_put(memcg); | |
3270 | ||
d0ce0e47 | 3271 | return folio; |
8f34af6f JZ |
3272 | |
3273 | out_uncharge_cgroup: | |
3274 | hugetlb_cgroup_uncharge_cgroup(idx, pages_per_huge_page(h), h_cg); | |
08cf9faf MA |
3275 | out_uncharge_cgroup_reservation: |
3276 | if (deferred_reserve) | |
3277 | hugetlb_cgroup_uncharge_cgroup_rsvd(idx, pages_per_huge_page(h), | |
3278 | h_cg); | |
8f34af6f | 3279 | out_subpool_put: |
d85f69b0 | 3280 | if (map_chg || avoid_reserve) |
8f34af6f | 3281 | hugepage_subpool_put_pages(spool, 1); |
8cba9576 | 3282 | out_end_reservation: |
feba16e2 | 3283 | vma_end_reservation(h, vma, addr); |
8cba9576 NP |
3284 | if (!memcg_charge_ret) |
3285 | mem_cgroup_cancel_charge(memcg, nr_pages); | |
3286 | mem_cgroup_put(memcg); | |
8f34af6f | 3287 | return ERR_PTR(-ENOSPC); |
b45b5bd6 DG |
3288 | } |
3289 | ||
b5389086 | 3290 | int alloc_bootmem_huge_page(struct hstate *h, int nid) |
e24a1307 | 3291 | __attribute__ ((weak, alias("__alloc_bootmem_huge_page"))); |
b5389086 | 3292 | int __alloc_bootmem_huge_page(struct hstate *h, int nid) |
aa888a74 | 3293 | { |
b5389086 | 3294 | struct huge_bootmem_page *m = NULL; /* initialize for clang */ |
b2261026 | 3295 | int nr_nodes, node; |
aa888a74 | 3296 | |
b5389086 ZY |
3297 | /* do node specific alloc */ |
3298 | if (nid != NUMA_NO_NODE) { | |
3299 | m = memblock_alloc_try_nid_raw(huge_page_size(h), huge_page_size(h), | |
3300 | 0, MEMBLOCK_ALLOC_ACCESSIBLE, nid); | |
3301 | if (!m) | |
3302 | return 0; | |
3303 | goto found; | |
3304 | } | |
3305 | /* allocate from next node when distributing huge pages */ | |
b2261026 | 3306 | for_each_node_mask_to_alloc(h, nr_nodes, node, &node_states[N_MEMORY]) { |
b5389086 | 3307 | m = memblock_alloc_try_nid_raw( |
8b89a116 | 3308 | huge_page_size(h), huge_page_size(h), |
97ad1087 | 3309 | 0, MEMBLOCK_ALLOC_ACCESSIBLE, node); |
b5389086 ZY |
3310 | /* |
3311 | * Use the beginning of the huge page to store the | |
3312 | * huge_bootmem_page struct (until gather_bootmem | |
3313 | * puts them into the mem_map). | |
3314 | */ | |
3315 | if (!m) | |
3316 | return 0; | |
3317 | goto found; | |
aa888a74 | 3318 | } |
aa888a74 AK |
3319 | |
3320 | found: | |
fde1c4ec UA |
3321 | |
3322 | /* | |
3323 | * Only initialize the head struct page in memmap_init_reserved_pages, | |
3324 | * rest of the struct pages will be initialized by the HugeTLB | |
3325 | * subsystem itself. | |
3326 | * The head struct page is used to get folio information by the HugeTLB | |
3327 | * subsystem like zone id and node id. | |
3328 | */ | |
3329 | memblock_reserved_mark_noinit(virt_to_phys((void *)m + PAGE_SIZE), | |
3330 | huge_page_size(h) - PAGE_SIZE); | |
aa888a74 | 3331 | /* Put them into a private list first because mem_map is not up yet */ |
330d6e48 | 3332 | INIT_LIST_HEAD(&m->list); |
aa888a74 AK |
3333 | list_add(&m->list, &huge_boot_pages); |
3334 | m->hstate = h; | |
3335 | return 1; | |
3336 | } | |
3337 | ||
fde1c4ec UA |
3338 | /* Initialize [start_page:end_page_number] tail struct pages of a hugepage */ |
3339 | static void __init hugetlb_folio_init_tail_vmemmap(struct folio *folio, | |
3340 | unsigned long start_page_number, | |
3341 | unsigned long end_page_number) | |
3342 | { | |
3343 | enum zone_type zone = zone_idx(folio_zone(folio)); | |
3344 | int nid = folio_nid(folio); | |
3345 | unsigned long head_pfn = folio_pfn(folio); | |
3346 | unsigned long pfn, end_pfn = head_pfn + end_page_number; | |
3347 | int ret; | |
3348 | ||
3349 | for (pfn = head_pfn + start_page_number; pfn < end_pfn; pfn++) { | |
3350 | struct page *page = pfn_to_page(pfn); | |
3351 | ||
3352 | __init_single_page(page, pfn, zone, nid); | |
3353 | prep_compound_tail((struct page *)folio, pfn - head_pfn); | |
3354 | ret = page_ref_freeze(page, 1); | |
3355 | VM_BUG_ON(!ret); | |
3356 | } | |
3357 | } | |
3358 | ||
3359 | static void __init hugetlb_folio_init_vmemmap(struct folio *folio, | |
3360 | struct hstate *h, | |
3361 | unsigned long nr_pages) | |
3362 | { | |
3363 | int ret; | |
3364 | ||
3365 | /* Prepare folio head */ | |
3366 | __folio_clear_reserved(folio); | |
3367 | __folio_set_head(folio); | |
a48bf7b4 | 3368 | ret = folio_ref_freeze(folio, 1); |
fde1c4ec UA |
3369 | VM_BUG_ON(!ret); |
3370 | /* Initialize the necessary tail struct pages */ | |
3371 | hugetlb_folio_init_tail_vmemmap(folio, 1, nr_pages); | |
3372 | prep_compound_head((struct page *)folio, huge_page_order(h)); | |
3373 | } | |
3374 | ||
79359d6d MK |
3375 | static void __init prep_and_add_bootmem_folios(struct hstate *h, |
3376 | struct list_head *folio_list) | |
3377 | { | |
3378 | unsigned long flags; | |
3379 | struct folio *folio, *tmp_f; | |
3380 | ||
3381 | /* Send list for bulk vmemmap optimization processing */ | |
3382 | hugetlb_vmemmap_optimize_folios(h, folio_list); | |
3383 | ||
3384 | /* Add all new pool pages to free lists in one lock cycle */ | |
3385 | spin_lock_irqsave(&hugetlb_lock, flags); | |
3386 | list_for_each_entry_safe(folio, tmp_f, folio_list, lru) { | |
3387 | if (!folio_test_hugetlb_vmemmap_optimized(folio)) { | |
3388 | /* | |
3389 | * If HVO fails, initialize all tail struct pages | |
3390 | * We do not worry about potential long lock hold | |
3391 | * time as this is early in boot and there should | |
3392 | * be no contention. | |
3393 | */ | |
3394 | hugetlb_folio_init_tail_vmemmap(folio, | |
3395 | HUGETLB_VMEMMAP_RESERVE_PAGES, | |
3396 | pages_per_huge_page(h)); | |
3397 | } | |
3398 | __prep_account_new_huge_page(h, folio_nid(folio)); | |
3399 | enqueue_hugetlb_folio(h, folio); | |
3400 | } | |
3401 | spin_unlock_irqrestore(&hugetlb_lock, flags); | |
3402 | } | |
3403 | ||
48b8d744 MK |
3404 | /* |
3405 | * Put bootmem huge pages into the standard lists after mem_map is up. | |
3406 | * Note: This only applies to gigantic (order > MAX_ORDER) pages. | |
3407 | */ | |
aa888a74 AK |
3408 | static void __init gather_bootmem_prealloc(void) |
3409 | { | |
d67e32f2 | 3410 | LIST_HEAD(folio_list); |
aa888a74 | 3411 | struct huge_bootmem_page *m; |
d67e32f2 | 3412 | struct hstate *h = NULL, *prev_h = NULL; |
aa888a74 AK |
3413 | |
3414 | list_for_each_entry(m, &huge_boot_pages, list) { | |
40d18ebf | 3415 | struct page *page = virt_to_page(m); |
fde1c4ec | 3416 | struct folio *folio = (void *)page; |
d67e32f2 MK |
3417 | |
3418 | h = m->hstate; | |
3419 | /* | |
3420 | * It is possible to have multiple huge page sizes (hstates) | |
3421 | * in this list. If so, process each size separately. | |
3422 | */ | |
3423 | if (h != prev_h && prev_h != NULL) | |
79359d6d | 3424 | prep_and_add_bootmem_folios(prev_h, &folio_list); |
d67e32f2 | 3425 | prev_h = h; |
ee8f248d | 3426 | |
48b8d744 | 3427 | VM_BUG_ON(!hstate_is_gigantic(h)); |
d1c60955 | 3428 | WARN_ON(folio_ref_count(folio) != 1); |
fde1c4ec UA |
3429 | |
3430 | hugetlb_folio_init_vmemmap(folio, h, | |
3431 | HUGETLB_VMEMMAP_RESERVE_PAGES); | |
79359d6d | 3432 | init_new_hugetlb_folio(h, folio); |
d67e32f2 | 3433 | list_add(&folio->lru, &folio_list); |
af0fb9df | 3434 | |
b0320c7b | 3435 | /* |
48b8d744 MK |
3436 | * We need to restore the 'stolen' pages to totalram_pages |
3437 | * in order to fix confusing memory reports from free(1) and | |
3438 | * other side-effects, like CommitLimit going negative. | |
b0320c7b | 3439 | */ |
48b8d744 | 3440 | adjust_managed_page_count(page, pages_per_huge_page(h)); |
520495fe | 3441 | cond_resched(); |
aa888a74 | 3442 | } |
d67e32f2 | 3443 | |
79359d6d | 3444 | prep_and_add_bootmem_folios(h, &folio_list); |
aa888a74 | 3445 | } |
fde1c4ec | 3446 | |
b5389086 ZY |
3447 | static void __init hugetlb_hstate_alloc_pages_onenode(struct hstate *h, int nid) |
3448 | { | |
3449 | unsigned long i; | |
3450 | char buf[32]; | |
3451 | ||
3452 | for (i = 0; i < h->max_huge_pages_node[nid]; ++i) { | |
3453 | if (hstate_is_gigantic(h)) { | |
3454 | if (!alloc_bootmem_huge_page(h, nid)) | |
3455 | break; | |
3456 | } else { | |
19fc1a7e | 3457 | struct folio *folio; |
b5389086 ZY |
3458 | gfp_t gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE; |
3459 | ||
19fc1a7e | 3460 | folio = alloc_fresh_hugetlb_folio(h, gfp_mask, nid, |
b5389086 | 3461 | &node_states[N_MEMORY], NULL); |
19fc1a7e | 3462 | if (!folio) |
b5389086 | 3463 | break; |
454a00c4 | 3464 | free_huge_folio(folio); /* free it into the hugepage allocator */ |
b5389086 ZY |
3465 | } |
3466 | cond_resched(); | |
3467 | } | |
3468 | if (i == h->max_huge_pages_node[nid]) | |
3469 | return; | |
3470 | ||
3471 | string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32); | |
3472 | pr_warn("HugeTLB: allocating %u of page size %s failed node%d. Only allocated %lu hugepages.\n", | |
3473 | h->max_huge_pages_node[nid], buf, nid, i); | |
3474 | h->max_huge_pages -= (h->max_huge_pages_node[nid] - i); | |
3475 | h->max_huge_pages_node[nid] = i; | |
3476 | } | |
aa888a74 | 3477 | |
d67e32f2 MK |
3478 | /* |
3479 | * NOTE: this routine is called in different contexts for gigantic and | |
3480 | * non-gigantic pages. | |
3481 | * - For gigantic pages, this is called early in the boot process and | |
3482 | * pages are allocated from memblock allocated or something similar. | |
3483 | * Gigantic pages are actually added to pools later with the routine | |
3484 | * gather_bootmem_prealloc. | |
3485 | * - For non-gigantic pages, this is called later in the boot process after | |
3486 | * all of mm is up and functional. Pages are allocated from buddy and | |
3487 | * then added to hugetlb pools. | |
3488 | */ | |
8faa8b07 | 3489 | static void __init hugetlb_hstate_alloc_pages(struct hstate *h) |
1da177e4 LT |
3490 | { |
3491 | unsigned long i; | |
d67e32f2 MK |
3492 | struct folio *folio; |
3493 | LIST_HEAD(folio_list); | |
f60858f9 | 3494 | nodemask_t *node_alloc_noretry; |
b5389086 ZY |
3495 | bool node_specific_alloc = false; |
3496 | ||
3497 | /* skip gigantic hugepages allocation if hugetlb_cma enabled */ | |
3498 | if (hstate_is_gigantic(h) && hugetlb_cma_size) { | |
3499 | pr_warn_once("HugeTLB: hugetlb_cma is enabled, skip boot time allocation\n"); | |
3500 | return; | |
3501 | } | |
3502 | ||
3503 | /* do node specific alloc */ | |
0a7a0f6f | 3504 | for_each_online_node(i) { |
b5389086 ZY |
3505 | if (h->max_huge_pages_node[i] > 0) { |
3506 | hugetlb_hstate_alloc_pages_onenode(h, i); | |
3507 | node_specific_alloc = true; | |
3508 | } | |
3509 | } | |
f60858f9 | 3510 | |
b5389086 ZY |
3511 | if (node_specific_alloc) |
3512 | return; | |
3513 | ||
3514 | /* below will do all node balanced alloc */ | |
f60858f9 MK |
3515 | if (!hstate_is_gigantic(h)) { |
3516 | /* | |
3517 | * Bit mask controlling how hard we retry per-node allocations. | |
3518 | * Ignore errors as lower level routines can deal with | |
3519 | * node_alloc_noretry == NULL. If this kmalloc fails at boot | |
3520 | * time, we are likely in bigger trouble. | |
3521 | */ | |
3522 | node_alloc_noretry = kmalloc(sizeof(*node_alloc_noretry), | |
3523 | GFP_KERNEL); | |
3524 | } else { | |
3525 | /* allocations done at boot time */ | |
3526 | node_alloc_noretry = NULL; | |
3527 | } | |
3528 | ||
3529 | /* bit mask controlling how hard we retry per-node allocations */ | |
3530 | if (node_alloc_noretry) | |
3531 | nodes_clear(*node_alloc_noretry); | |
a5516438 | 3532 | |
e5ff2159 | 3533 | for (i = 0; i < h->max_huge_pages; ++i) { |
bae7f4ae | 3534 | if (hstate_is_gigantic(h)) { |
d67e32f2 MK |
3535 | /* |
3536 | * gigantic pages not added to list as they are not | |
3537 | * added to pools now. | |
3538 | */ | |
b5389086 | 3539 | if (!alloc_bootmem_huge_page(h, NUMA_NO_NODE)) |
aa888a74 | 3540 | break; |
d67e32f2 MK |
3541 | } else { |
3542 | folio = alloc_pool_huge_folio(h, &node_states[N_MEMORY], | |
3543 | node_alloc_noretry); | |
3544 | if (!folio) | |
3545 | break; | |
3546 | list_add(&folio->lru, &folio_list); | |
3547 | } | |
69ed779a | 3548 | cond_resched(); |
1da177e4 | 3549 | } |
d67e32f2 MK |
3550 | |
3551 | /* list will be empty if hstate_is_gigantic */ | |
3552 | prep_and_add_allocated_folios(h, &folio_list); | |
3553 | ||
d715cf80 LH |
3554 | if (i < h->max_huge_pages) { |
3555 | char buf[32]; | |
3556 | ||
c6247f72 | 3557 | string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32); |
d715cf80 LH |
3558 | pr_warn("HugeTLB: allocating %lu of page size %s failed. Only allocated %lu hugepages.\n", |
3559 | h->max_huge_pages, buf, i); | |
3560 | h->max_huge_pages = i; | |
3561 | } | |
f60858f9 | 3562 | kfree(node_alloc_noretry); |
e5ff2159 AK |
3563 | } |
3564 | ||
3565 | static void __init hugetlb_init_hstates(void) | |
3566 | { | |
79dfc695 | 3567 | struct hstate *h, *h2; |
e5ff2159 AK |
3568 | |
3569 | for_each_hstate(h) { | |
8faa8b07 | 3570 | /* oversize hugepages were init'ed in early boot */ |
bae7f4ae | 3571 | if (!hstate_is_gigantic(h)) |
8faa8b07 | 3572 | hugetlb_hstate_alloc_pages(h); |
79dfc695 MK |
3573 | |
3574 | /* | |
3575 | * Set demote order for each hstate. Note that | |
3576 | * h->demote_order is initially 0. | |
3577 | * - We can not demote gigantic pages if runtime freeing | |
3578 | * is not supported, so skip this. | |
a01f4390 MK |
3579 | * - If CMA allocation is possible, we can not demote |
3580 | * HUGETLB_PAGE_ORDER or smaller size pages. | |
79dfc695 MK |
3581 | */ |
3582 | if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) | |
3583 | continue; | |
a01f4390 MK |
3584 | if (hugetlb_cma_size && h->order <= HUGETLB_PAGE_ORDER) |
3585 | continue; | |
79dfc695 MK |
3586 | for_each_hstate(h2) { |
3587 | if (h2 == h) | |
3588 | continue; | |
3589 | if (h2->order < h->order && | |
3590 | h2->order > h->demote_order) | |
3591 | h->demote_order = h2->order; | |
3592 | } | |
e5ff2159 AK |
3593 | } |
3594 | } | |
3595 | ||
3596 | static void __init report_hugepages(void) | |
3597 | { | |
3598 | struct hstate *h; | |
3599 | ||
3600 | for_each_hstate(h) { | |
4abd32db | 3601 | char buf[32]; |
c6247f72 MW |
3602 | |
3603 | string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32); | |
6213834c | 3604 | pr_info("HugeTLB: registered %s page size, pre-allocated %ld pages\n", |
c6247f72 | 3605 | buf, h->free_huge_pages); |
6213834c MS |
3606 | pr_info("HugeTLB: %d KiB vmemmap can be freed for a %s page\n", |
3607 | hugetlb_vmemmap_optimizable_size(h) / SZ_1K, buf); | |
e5ff2159 AK |
3608 | } |
3609 | } | |
3610 | ||
1da177e4 | 3611 | #ifdef CONFIG_HIGHMEM |
6ae11b27 LS |
3612 | static void try_to_free_low(struct hstate *h, unsigned long count, |
3613 | nodemask_t *nodes_allowed) | |
1da177e4 | 3614 | { |
4415cc8d | 3615 | int i; |
1121828a | 3616 | LIST_HEAD(page_list); |
4415cc8d | 3617 | |
9487ca60 | 3618 | lockdep_assert_held(&hugetlb_lock); |
bae7f4ae | 3619 | if (hstate_is_gigantic(h)) |
aa888a74 AK |
3620 | return; |
3621 | ||
1121828a MK |
3622 | /* |
3623 | * Collect pages to be freed on a list, and free after dropping lock | |
3624 | */ | |
6ae11b27 | 3625 | for_each_node_mask(i, *nodes_allowed) { |
04bbfd84 | 3626 | struct folio *folio, *next; |
a5516438 | 3627 | struct list_head *freel = &h->hugepage_freelists[i]; |
04bbfd84 | 3628 | list_for_each_entry_safe(folio, next, freel, lru) { |
a5516438 | 3629 | if (count >= h->nr_huge_pages) |
1121828a | 3630 | goto out; |
04bbfd84 | 3631 | if (folio_test_highmem(folio)) |
1da177e4 | 3632 | continue; |
04bbfd84 MWO |
3633 | remove_hugetlb_folio(h, folio, false); |
3634 | list_add(&folio->lru, &page_list); | |
1da177e4 LT |
3635 | } |
3636 | } | |
1121828a MK |
3637 | |
3638 | out: | |
db71ef79 | 3639 | spin_unlock_irq(&hugetlb_lock); |
10c6ec49 | 3640 | update_and_free_pages_bulk(h, &page_list); |
db71ef79 | 3641 | spin_lock_irq(&hugetlb_lock); |
1da177e4 LT |
3642 | } |
3643 | #else | |
6ae11b27 LS |
3644 | static inline void try_to_free_low(struct hstate *h, unsigned long count, |
3645 | nodemask_t *nodes_allowed) | |
1da177e4 LT |
3646 | { |
3647 | } | |
3648 | #endif | |
3649 | ||
20a0307c WF |
3650 | /* |
3651 | * Increment or decrement surplus_huge_pages. Keep node-specific counters | |
3652 | * balanced by operating on them in a round-robin fashion. | |
3653 | * Returns 1 if an adjustment was made. | |
3654 | */ | |
6ae11b27 LS |
3655 | static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed, |
3656 | int delta) | |
20a0307c | 3657 | { |
b2261026 | 3658 | int nr_nodes, node; |
20a0307c | 3659 | |
9487ca60 | 3660 | lockdep_assert_held(&hugetlb_lock); |
20a0307c | 3661 | VM_BUG_ON(delta != -1 && delta != 1); |
20a0307c | 3662 | |
b2261026 JK |
3663 | if (delta < 0) { |
3664 | for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) { | |
3665 | if (h->surplus_huge_pages_node[node]) | |
3666 | goto found; | |
e8c5c824 | 3667 | } |
b2261026 JK |
3668 | } else { |
3669 | for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { | |
3670 | if (h->surplus_huge_pages_node[node] < | |
3671 | h->nr_huge_pages_node[node]) | |
3672 | goto found; | |
e8c5c824 | 3673 | } |
b2261026 JK |
3674 | } |
3675 | return 0; | |
20a0307c | 3676 | |
b2261026 JK |
3677 | found: |
3678 | h->surplus_huge_pages += delta; | |
3679 | h->surplus_huge_pages_node[node] += delta; | |
3680 | return 1; | |
20a0307c WF |
3681 | } |
3682 | ||
a5516438 | 3683 | #define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages) |
fd875dca | 3684 | static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid, |
4eb0716e | 3685 | nodemask_t *nodes_allowed) |
1da177e4 | 3686 | { |
d67e32f2 MK |
3687 | unsigned long min_count; |
3688 | unsigned long allocated; | |
3689 | struct folio *folio; | |
10c6ec49 | 3690 | LIST_HEAD(page_list); |
f60858f9 MK |
3691 | NODEMASK_ALLOC(nodemask_t, node_alloc_noretry, GFP_KERNEL); |
3692 | ||
3693 | /* | |
3694 | * Bit mask controlling how hard we retry per-node allocations. | |
3695 | * If we can not allocate the bit mask, do not attempt to allocate | |
3696 | * the requested huge pages. | |
3697 | */ | |
3698 | if (node_alloc_noretry) | |
3699 | nodes_clear(*node_alloc_noretry); | |
3700 | else | |
3701 | return -ENOMEM; | |
1da177e4 | 3702 | |
29383967 MK |
3703 | /* |
3704 | * resize_lock mutex prevents concurrent adjustments to number of | |
3705 | * pages in hstate via the proc/sysfs interfaces. | |
3706 | */ | |
3707 | mutex_lock(&h->resize_lock); | |
b65d4adb | 3708 | flush_free_hpage_work(h); |
db71ef79 | 3709 | spin_lock_irq(&hugetlb_lock); |
4eb0716e | 3710 | |
fd875dca MK |
3711 | /* |
3712 | * Check for a node specific request. | |
3713 | * Changing node specific huge page count may require a corresponding | |
3714 | * change to the global count. In any case, the passed node mask | |
3715 | * (nodes_allowed) will restrict alloc/free to the specified node. | |
3716 | */ | |
3717 | if (nid != NUMA_NO_NODE) { | |
3718 | unsigned long old_count = count; | |
3719 | ||
b72b3c9c XH |
3720 | count += persistent_huge_pages(h) - |
3721 | (h->nr_huge_pages_node[nid] - | |
3722 | h->surplus_huge_pages_node[nid]); | |
fd875dca MK |
3723 | /* |
3724 | * User may have specified a large count value which caused the | |
3725 | * above calculation to overflow. In this case, they wanted | |
3726 | * to allocate as many huge pages as possible. Set count to | |
3727 | * largest possible value to align with their intention. | |
3728 | */ | |
3729 | if (count < old_count) | |
3730 | count = ULONG_MAX; | |
3731 | } | |
3732 | ||
4eb0716e AG |
3733 | /* |
3734 | * Gigantic pages runtime allocation depend on the capability for large | |
3735 | * page range allocation. | |
3736 | * If the system does not provide this feature, return an error when | |
3737 | * the user tries to allocate gigantic pages but let the user free the | |
3738 | * boottime allocated gigantic pages. | |
3739 | */ | |
3740 | if (hstate_is_gigantic(h) && !IS_ENABLED(CONFIG_CONTIG_ALLOC)) { | |
3741 | if (count > persistent_huge_pages(h)) { | |
db71ef79 | 3742 | spin_unlock_irq(&hugetlb_lock); |
29383967 | 3743 | mutex_unlock(&h->resize_lock); |
f60858f9 | 3744 | NODEMASK_FREE(node_alloc_noretry); |
4eb0716e AG |
3745 | return -EINVAL; |
3746 | } | |
3747 | /* Fall through to decrease pool */ | |
3748 | } | |
aa888a74 | 3749 | |
7893d1d5 AL |
3750 | /* |
3751 | * Increase the pool size | |
3752 | * First take pages out of surplus state. Then make up the | |
3753 | * remaining difference by allocating fresh huge pages. | |
d1c3fb1f | 3754 | * |
3a740e8b | 3755 | * We might race with alloc_surplus_hugetlb_folio() here and be unable |
d1c3fb1f NA |
3756 | * to convert a surplus huge page to a normal huge page. That is |
3757 | * not critical, though, it just means the overall size of the | |
3758 | * pool might be one hugepage larger than it needs to be, but | |
3759 | * within all the constraints specified by the sysctls. | |
7893d1d5 | 3760 | */ |
a5516438 | 3761 | while (h->surplus_huge_pages && count > persistent_huge_pages(h)) { |
6ae11b27 | 3762 | if (!adjust_pool_surplus(h, nodes_allowed, -1)) |
7893d1d5 AL |
3763 | break; |
3764 | } | |
3765 | ||
d67e32f2 MK |
3766 | allocated = 0; |
3767 | while (count > (persistent_huge_pages(h) + allocated)) { | |
7893d1d5 AL |
3768 | /* |
3769 | * If this allocation races such that we no longer need the | |
454a00c4 | 3770 | * page, free_huge_folio will handle it by freeing the page |
7893d1d5 AL |
3771 | * and reducing the surplus. |
3772 | */ | |
db71ef79 | 3773 | spin_unlock_irq(&hugetlb_lock); |
649920c6 JH |
3774 | |
3775 | /* yield cpu to avoid soft lockup */ | |
3776 | cond_resched(); | |
3777 | ||
d67e32f2 | 3778 | folio = alloc_pool_huge_folio(h, nodes_allowed, |
f60858f9 | 3779 | node_alloc_noretry); |
d67e32f2 MK |
3780 | if (!folio) { |
3781 | prep_and_add_allocated_folios(h, &page_list); | |
3782 | spin_lock_irq(&hugetlb_lock); | |
7893d1d5 | 3783 | goto out; |
d67e32f2 MK |
3784 | } |
3785 | ||
3786 | list_add(&folio->lru, &page_list); | |
3787 | allocated++; | |
7893d1d5 | 3788 | |
536240f2 | 3789 | /* Bail for signals. Probably ctrl-c from user */ |
d67e32f2 MK |
3790 | if (signal_pending(current)) { |
3791 | prep_and_add_allocated_folios(h, &page_list); | |
3792 | spin_lock_irq(&hugetlb_lock); | |
536240f2 | 3793 | goto out; |
d67e32f2 MK |
3794 | } |
3795 | ||
3796 | spin_lock_irq(&hugetlb_lock); | |
3797 | } | |
3798 | ||
3799 | /* Add allocated pages to the pool */ | |
3800 | if (!list_empty(&page_list)) { | |
3801 | spin_unlock_irq(&hugetlb_lock); | |
3802 | prep_and_add_allocated_folios(h, &page_list); | |
3803 | spin_lock_irq(&hugetlb_lock); | |
7893d1d5 | 3804 | } |
7893d1d5 AL |
3805 | |
3806 | /* | |
3807 | * Decrease the pool size | |
3808 | * First return free pages to the buddy allocator (being careful | |
3809 | * to keep enough around to satisfy reservations). Then place | |
3810 | * pages into surplus state as needed so the pool will shrink | |
3811 | * to the desired size as pages become free. | |
d1c3fb1f NA |
3812 | * |
3813 | * By placing pages into the surplus state independent of the | |
3814 | * overcommit value, we are allowing the surplus pool size to | |
3815 | * exceed overcommit. There are few sane options here. Since | |
3a740e8b | 3816 | * alloc_surplus_hugetlb_folio() is checking the global counter, |
d1c3fb1f NA |
3817 | * though, we'll note that we're not allowed to exceed surplus |
3818 | * and won't grow the pool anywhere else. Not until one of the | |
3819 | * sysctls are changed, or the surplus pages go out of use. | |
7893d1d5 | 3820 | */ |
a5516438 | 3821 | min_count = h->resv_huge_pages + h->nr_huge_pages - h->free_huge_pages; |
6b0c880d | 3822 | min_count = max(count, min_count); |
6ae11b27 | 3823 | try_to_free_low(h, min_count, nodes_allowed); |
10c6ec49 MK |
3824 | |
3825 | /* | |
3826 | * Collect pages to be removed on list without dropping lock | |
3827 | */ | |
a5516438 | 3828 | while (min_count < persistent_huge_pages(h)) { |
d5b43e96 MWO |
3829 | folio = remove_pool_hugetlb_folio(h, nodes_allowed, 0); |
3830 | if (!folio) | |
1da177e4 | 3831 | break; |
10c6ec49 | 3832 | |
d5b43e96 | 3833 | list_add(&folio->lru, &page_list); |
1da177e4 | 3834 | } |
10c6ec49 | 3835 | /* free the pages after dropping lock */ |
db71ef79 | 3836 | spin_unlock_irq(&hugetlb_lock); |
10c6ec49 | 3837 | update_and_free_pages_bulk(h, &page_list); |
b65d4adb | 3838 | flush_free_hpage_work(h); |
db71ef79 | 3839 | spin_lock_irq(&hugetlb_lock); |
10c6ec49 | 3840 | |
a5516438 | 3841 | while (count < persistent_huge_pages(h)) { |
6ae11b27 | 3842 | if (!adjust_pool_surplus(h, nodes_allowed, 1)) |
7893d1d5 AL |
3843 | break; |
3844 | } | |
3845 | out: | |
4eb0716e | 3846 | h->max_huge_pages = persistent_huge_pages(h); |
db71ef79 | 3847 | spin_unlock_irq(&hugetlb_lock); |
29383967 | 3848 | mutex_unlock(&h->resize_lock); |
4eb0716e | 3849 | |
f60858f9 MK |
3850 | NODEMASK_FREE(node_alloc_noretry); |
3851 | ||
4eb0716e | 3852 | return 0; |
1da177e4 LT |
3853 | } |
3854 | ||
bdd7be07 | 3855 | static int demote_free_hugetlb_folio(struct hstate *h, struct folio *folio) |
8531fc6f | 3856 | { |
bdd7be07 | 3857 | int i, nid = folio_nid(folio); |
8531fc6f | 3858 | struct hstate *target_hstate; |
31731452 | 3859 | struct page *subpage; |
bdd7be07 | 3860 | struct folio *inner_folio; |
8531fc6f MK |
3861 | int rc = 0; |
3862 | ||
3863 | target_hstate = size_to_hstate(PAGE_SIZE << h->demote_order); | |
3864 | ||
cfd5082b | 3865 | remove_hugetlb_folio_for_demote(h, folio, false); |
8531fc6f MK |
3866 | spin_unlock_irq(&hugetlb_lock); |
3867 | ||
d8f5f7e4 MK |
3868 | /* |
3869 | * If vmemmap already existed for folio, the remove routine above would | |
3870 | * have cleared the hugetlb folio flag. Hence the folio is technically | |
c5ad3233 | 3871 | * no longer a hugetlb folio. hugetlb_vmemmap_restore_folio can only be |
d8f5f7e4 MK |
3872 | * passed hugetlb folios and will BUG otherwise. |
3873 | */ | |
3874 | if (folio_test_hugetlb(folio)) { | |
c5ad3233 | 3875 | rc = hugetlb_vmemmap_restore_folio(h, folio); |
d8f5f7e4 MK |
3876 | if (rc) { |
3877 | /* Allocation of vmemmmap failed, we can not demote folio */ | |
3878 | spin_lock_irq(&hugetlb_lock); | |
3879 | folio_ref_unfreeze(folio, 1); | |
3880 | add_hugetlb_folio(h, folio, false); | |
3881 | return rc; | |
3882 | } | |
8531fc6f MK |
3883 | } |
3884 | ||
3885 | /* | |
911565b8 | 3886 | * Use destroy_compound_hugetlb_folio_for_demote for all huge page |
bdd7be07 | 3887 | * sizes as it will not ref count folios. |
8531fc6f | 3888 | */ |
911565b8 | 3889 | destroy_compound_hugetlb_folio_for_demote(folio, huge_page_order(h)); |
8531fc6f MK |
3890 | |
3891 | /* | |
3892 | * Taking target hstate mutex synchronizes with set_max_huge_pages. | |
3893 | * Without the mutex, pages added to target hstate could be marked | |
3894 | * as surplus. | |
3895 | * | |
3896 | * Note that we already hold h->resize_lock. To prevent deadlock, | |
3897 | * use the convention of always taking larger size hstate mutex first. | |
3898 | */ | |
3899 | mutex_lock(&target_hstate->resize_lock); | |
3900 | for (i = 0; i < pages_per_huge_page(h); | |
3901 | i += pages_per_huge_page(target_hstate)) { | |
bdd7be07 SK |
3902 | subpage = folio_page(folio, i); |
3903 | inner_folio = page_folio(subpage); | |
8531fc6f | 3904 | if (hstate_is_gigantic(target_hstate)) |
bdd7be07 | 3905 | prep_compound_gigantic_folio_for_demote(inner_folio, |
8531fc6f MK |
3906 | target_hstate->order); |
3907 | else | |
31731452 | 3908 | prep_compound_page(subpage, target_hstate->order); |
bdd7be07 SK |
3909 | folio_change_private(inner_folio, NULL); |
3910 | prep_new_hugetlb_folio(target_hstate, inner_folio, nid); | |
454a00c4 | 3911 | free_huge_folio(inner_folio); |
8531fc6f MK |
3912 | } |
3913 | mutex_unlock(&target_hstate->resize_lock); | |
3914 | ||
3915 | spin_lock_irq(&hugetlb_lock); | |
3916 | ||
3917 | /* | |
3918 | * Not absolutely necessary, but for consistency update max_huge_pages | |
3919 | * based on pool changes for the demoted page. | |
3920 | */ | |
3921 | h->max_huge_pages--; | |
a43a83c7 ML |
3922 | target_hstate->max_huge_pages += |
3923 | pages_per_huge_page(h) / pages_per_huge_page(target_hstate); | |
8531fc6f MK |
3924 | |
3925 | return rc; | |
3926 | } | |
3927 | ||
79dfc695 MK |
3928 | static int demote_pool_huge_page(struct hstate *h, nodemask_t *nodes_allowed) |
3929 | __must_hold(&hugetlb_lock) | |
3930 | { | |
8531fc6f | 3931 | int nr_nodes, node; |
bdd7be07 | 3932 | struct folio *folio; |
79dfc695 MK |
3933 | |
3934 | lockdep_assert_held(&hugetlb_lock); | |
3935 | ||
3936 | /* We should never get here if no demote order */ | |
3937 | if (!h->demote_order) { | |
3938 | pr_warn("HugeTLB: NULL demote order passed to demote_pool_huge_page.\n"); | |
3939 | return -EINVAL; /* internal error */ | |
3940 | } | |
3941 | ||
8531fc6f | 3942 | for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { |
bdd7be07 SK |
3943 | list_for_each_entry(folio, &h->hugepage_freelists[node], lru) { |
3944 | if (folio_test_hwpoison(folio)) | |
5a317412 | 3945 | continue; |
bdd7be07 | 3946 | return demote_free_hugetlb_folio(h, folio); |
8531fc6f MK |
3947 | } |
3948 | } | |
3949 | ||
5a317412 MK |
3950 | /* |
3951 | * Only way to get here is if all pages on free lists are poisoned. | |
3952 | * Return -EBUSY so that caller will not retry. | |
3953 | */ | |
3954 | return -EBUSY; | |
79dfc695 MK |
3955 | } |
3956 | ||
a3437870 NA |
3957 | #define HSTATE_ATTR_RO(_name) \ |
3958 | static struct kobj_attribute _name##_attr = __ATTR_RO(_name) | |
3959 | ||
79dfc695 MK |
3960 | #define HSTATE_ATTR_WO(_name) \ |
3961 | static struct kobj_attribute _name##_attr = __ATTR_WO(_name) | |
3962 | ||
a3437870 | 3963 | #define HSTATE_ATTR(_name) \ |
98bc26ac | 3964 | static struct kobj_attribute _name##_attr = __ATTR_RW(_name) |
a3437870 NA |
3965 | |
3966 | static struct kobject *hugepages_kobj; | |
3967 | static struct kobject *hstate_kobjs[HUGE_MAX_HSTATE]; | |
3968 | ||
9a305230 LS |
3969 | static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp); |
3970 | ||
3971 | static struct hstate *kobj_to_hstate(struct kobject *kobj, int *nidp) | |
a3437870 NA |
3972 | { |
3973 | int i; | |
9a305230 | 3974 | |
a3437870 | 3975 | for (i = 0; i < HUGE_MAX_HSTATE; i++) |
9a305230 LS |
3976 | if (hstate_kobjs[i] == kobj) { |
3977 | if (nidp) | |
3978 | *nidp = NUMA_NO_NODE; | |
a3437870 | 3979 | return &hstates[i]; |
9a305230 LS |
3980 | } |
3981 | ||
3982 | return kobj_to_node_hstate(kobj, nidp); | |
a3437870 NA |
3983 | } |
3984 | ||
06808b08 | 3985 | static ssize_t nr_hugepages_show_common(struct kobject *kobj, |
a3437870 NA |
3986 | struct kobj_attribute *attr, char *buf) |
3987 | { | |
9a305230 LS |
3988 | struct hstate *h; |
3989 | unsigned long nr_huge_pages; | |
3990 | int nid; | |
3991 | ||
3992 | h = kobj_to_hstate(kobj, &nid); | |
3993 | if (nid == NUMA_NO_NODE) | |
3994 | nr_huge_pages = h->nr_huge_pages; | |
3995 | else | |
3996 | nr_huge_pages = h->nr_huge_pages_node[nid]; | |
3997 | ||
ae7a927d | 3998 | return sysfs_emit(buf, "%lu\n", nr_huge_pages); |
a3437870 | 3999 | } |
adbe8726 | 4000 | |
238d3c13 DR |
4001 | static ssize_t __nr_hugepages_store_common(bool obey_mempolicy, |
4002 | struct hstate *h, int nid, | |
4003 | unsigned long count, size_t len) | |
a3437870 NA |
4004 | { |
4005 | int err; | |
2d0adf7e | 4006 | nodemask_t nodes_allowed, *n_mask; |
a3437870 | 4007 | |
2d0adf7e OS |
4008 | if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) |
4009 | return -EINVAL; | |
adbe8726 | 4010 | |
9a305230 LS |
4011 | if (nid == NUMA_NO_NODE) { |
4012 | /* | |
4013 | * global hstate attribute | |
4014 | */ | |
4015 | if (!(obey_mempolicy && | |
2d0adf7e OS |
4016 | init_nodemask_of_mempolicy(&nodes_allowed))) |
4017 | n_mask = &node_states[N_MEMORY]; | |
4018 | else | |
4019 | n_mask = &nodes_allowed; | |
4020 | } else { | |
9a305230 | 4021 | /* |
fd875dca MK |
4022 | * Node specific request. count adjustment happens in |
4023 | * set_max_huge_pages() after acquiring hugetlb_lock. | |
9a305230 | 4024 | */ |
2d0adf7e OS |
4025 | init_nodemask_of_node(&nodes_allowed, nid); |
4026 | n_mask = &nodes_allowed; | |
fd875dca | 4027 | } |
9a305230 | 4028 | |
2d0adf7e | 4029 | err = set_max_huge_pages(h, count, nid, n_mask); |
06808b08 | 4030 | |
4eb0716e | 4031 | return err ? err : len; |
06808b08 LS |
4032 | } |
4033 | ||
238d3c13 DR |
4034 | static ssize_t nr_hugepages_store_common(bool obey_mempolicy, |
4035 | struct kobject *kobj, const char *buf, | |
4036 | size_t len) | |
4037 | { | |
4038 | struct hstate *h; | |
4039 | unsigned long count; | |
4040 | int nid; | |
4041 | int err; | |
4042 | ||
4043 | err = kstrtoul(buf, 10, &count); | |
4044 | if (err) | |
4045 | return err; | |
4046 | ||
4047 | h = kobj_to_hstate(kobj, &nid); | |
4048 | return __nr_hugepages_store_common(obey_mempolicy, h, nid, count, len); | |
4049 | } | |
4050 | ||
06808b08 LS |
4051 | static ssize_t nr_hugepages_show(struct kobject *kobj, |
4052 | struct kobj_attribute *attr, char *buf) | |
4053 | { | |
4054 | return nr_hugepages_show_common(kobj, attr, buf); | |
4055 | } | |
4056 | ||
4057 | static ssize_t nr_hugepages_store(struct kobject *kobj, | |
4058 | struct kobj_attribute *attr, const char *buf, size_t len) | |
4059 | { | |
238d3c13 | 4060 | return nr_hugepages_store_common(false, kobj, buf, len); |
a3437870 NA |
4061 | } |
4062 | HSTATE_ATTR(nr_hugepages); | |
4063 | ||
06808b08 LS |
4064 | #ifdef CONFIG_NUMA |
4065 | ||
4066 | /* | |
4067 | * hstate attribute for optionally mempolicy-based constraint on persistent | |
4068 | * huge page alloc/free. | |
4069 | */ | |
4070 | static ssize_t nr_hugepages_mempolicy_show(struct kobject *kobj, | |
ae7a927d JP |
4071 | struct kobj_attribute *attr, |
4072 | char *buf) | |
06808b08 LS |
4073 | { |
4074 | return nr_hugepages_show_common(kobj, attr, buf); | |
4075 | } | |
4076 | ||
4077 | static ssize_t nr_hugepages_mempolicy_store(struct kobject *kobj, | |
4078 | struct kobj_attribute *attr, const char *buf, size_t len) | |
4079 | { | |
238d3c13 | 4080 | return nr_hugepages_store_common(true, kobj, buf, len); |
06808b08 LS |
4081 | } |
4082 | HSTATE_ATTR(nr_hugepages_mempolicy); | |
4083 | #endif | |
4084 | ||
4085 | ||
a3437870 NA |
4086 | static ssize_t nr_overcommit_hugepages_show(struct kobject *kobj, |
4087 | struct kobj_attribute *attr, char *buf) | |
4088 | { | |
9a305230 | 4089 | struct hstate *h = kobj_to_hstate(kobj, NULL); |
ae7a927d | 4090 | return sysfs_emit(buf, "%lu\n", h->nr_overcommit_huge_pages); |
a3437870 | 4091 | } |
adbe8726 | 4092 | |
a3437870 NA |
4093 | static ssize_t nr_overcommit_hugepages_store(struct kobject *kobj, |
4094 | struct kobj_attribute *attr, const char *buf, size_t count) | |
4095 | { | |
4096 | int err; | |
4097 | unsigned long input; | |
9a305230 | 4098 | struct hstate *h = kobj_to_hstate(kobj, NULL); |
a3437870 | 4099 | |
bae7f4ae | 4100 | if (hstate_is_gigantic(h)) |
adbe8726 EM |
4101 | return -EINVAL; |
4102 | ||
3dbb95f7 | 4103 | err = kstrtoul(buf, 10, &input); |
a3437870 | 4104 | if (err) |
73ae31e5 | 4105 | return err; |
a3437870 | 4106 | |
db71ef79 | 4107 | spin_lock_irq(&hugetlb_lock); |
a3437870 | 4108 | h->nr_overcommit_huge_pages = input; |
db71ef79 | 4109 | spin_unlock_irq(&hugetlb_lock); |
a3437870 NA |
4110 | |
4111 | return count; | |
4112 | } | |
4113 | HSTATE_ATTR(nr_overcommit_hugepages); | |
4114 | ||
4115 | static ssize_t free_hugepages_show(struct kobject *kobj, | |
4116 | struct kobj_attribute *attr, char *buf) | |
4117 | { | |
9a305230 LS |
4118 | struct hstate *h; |
4119 | unsigned long free_huge_pages; | |
4120 | int nid; | |
4121 | ||
4122 | h = kobj_to_hstate(kobj, &nid); | |
4123 | if (nid == NUMA_NO_NODE) | |
4124 | free_huge_pages = h->free_huge_pages; | |
4125 | else | |
4126 | free_huge_pages = h->free_huge_pages_node[nid]; | |
4127 | ||
ae7a927d | 4128 | return sysfs_emit(buf, "%lu\n", free_huge_pages); |
a3437870 NA |
4129 | } |
4130 | HSTATE_ATTR_RO(free_hugepages); | |
4131 | ||
4132 | static ssize_t resv_hugepages_show(struct kobject *kobj, | |
4133 | struct kobj_attribute *attr, char *buf) | |
4134 | { | |
9a305230 | 4135 | struct hstate *h = kobj_to_hstate(kobj, NULL); |
ae7a927d | 4136 | return sysfs_emit(buf, "%lu\n", h->resv_huge_pages); |
a3437870 NA |
4137 | } |
4138 | HSTATE_ATTR_RO(resv_hugepages); | |
4139 | ||
4140 | static ssize_t surplus_hugepages_show(struct kobject *kobj, | |
4141 | struct kobj_attribute *attr, char *buf) | |
4142 | { | |
9a305230 LS |
4143 | struct hstate *h; |
4144 | unsigned long surplus_huge_pages; | |
4145 | int nid; | |
4146 | ||
4147 | h = kobj_to_hstate(kobj, &nid); | |
4148 | if (nid == NUMA_NO_NODE) | |
4149 | surplus_huge_pages = h->surplus_huge_pages; | |
4150 | else | |
4151 | surplus_huge_pages = h->surplus_huge_pages_node[nid]; | |
4152 | ||
ae7a927d | 4153 | return sysfs_emit(buf, "%lu\n", surplus_huge_pages); |
a3437870 NA |
4154 | } |
4155 | HSTATE_ATTR_RO(surplus_hugepages); | |
4156 | ||
79dfc695 MK |
4157 | static ssize_t demote_store(struct kobject *kobj, |
4158 | struct kobj_attribute *attr, const char *buf, size_t len) | |
4159 | { | |
4160 | unsigned long nr_demote; | |
4161 | unsigned long nr_available; | |
4162 | nodemask_t nodes_allowed, *n_mask; | |
4163 | struct hstate *h; | |
8eeda55f | 4164 | int err; |
79dfc695 MK |
4165 | int nid; |
4166 | ||
4167 | err = kstrtoul(buf, 10, &nr_demote); | |
4168 | if (err) | |
4169 | return err; | |
4170 | h = kobj_to_hstate(kobj, &nid); | |
4171 | ||
4172 | if (nid != NUMA_NO_NODE) { | |
4173 | init_nodemask_of_node(&nodes_allowed, nid); | |
4174 | n_mask = &nodes_allowed; | |
4175 | } else { | |
4176 | n_mask = &node_states[N_MEMORY]; | |
4177 | } | |
4178 | ||
4179 | /* Synchronize with other sysfs operations modifying huge pages */ | |
4180 | mutex_lock(&h->resize_lock); | |
4181 | spin_lock_irq(&hugetlb_lock); | |
4182 | ||
4183 | while (nr_demote) { | |
4184 | /* | |
4185 | * Check for available pages to demote each time thorough the | |
4186 | * loop as demote_pool_huge_page will drop hugetlb_lock. | |
79dfc695 MK |
4187 | */ |
4188 | if (nid != NUMA_NO_NODE) | |
4189 | nr_available = h->free_huge_pages_node[nid]; | |
4190 | else | |
4191 | nr_available = h->free_huge_pages; | |
4192 | nr_available -= h->resv_huge_pages; | |
4193 | if (!nr_available) | |
4194 | break; | |
4195 | ||
4196 | err = demote_pool_huge_page(h, n_mask); | |
4197 | if (err) | |
4198 | break; | |
4199 | ||
4200 | nr_demote--; | |
4201 | } | |
4202 | ||
4203 | spin_unlock_irq(&hugetlb_lock); | |
4204 | mutex_unlock(&h->resize_lock); | |
4205 | ||
4206 | if (err) | |
4207 | return err; | |
4208 | return len; | |
4209 | } | |
4210 | HSTATE_ATTR_WO(demote); | |
4211 | ||
4212 | static ssize_t demote_size_show(struct kobject *kobj, | |
4213 | struct kobj_attribute *attr, char *buf) | |
4214 | { | |
12658abf | 4215 | struct hstate *h = kobj_to_hstate(kobj, NULL); |
79dfc695 MK |
4216 | unsigned long demote_size = (PAGE_SIZE << h->demote_order) / SZ_1K; |
4217 | ||
4218 | return sysfs_emit(buf, "%lukB\n", demote_size); | |
4219 | } | |
4220 | ||
4221 | static ssize_t demote_size_store(struct kobject *kobj, | |
4222 | struct kobj_attribute *attr, | |
4223 | const char *buf, size_t count) | |
4224 | { | |
4225 | struct hstate *h, *demote_hstate; | |
4226 | unsigned long demote_size; | |
4227 | unsigned int demote_order; | |
79dfc695 MK |
4228 | |
4229 | demote_size = (unsigned long)memparse(buf, NULL); | |
4230 | ||
4231 | demote_hstate = size_to_hstate(demote_size); | |
4232 | if (!demote_hstate) | |
4233 | return -EINVAL; | |
4234 | demote_order = demote_hstate->order; | |
a01f4390 MK |
4235 | if (demote_order < HUGETLB_PAGE_ORDER) |
4236 | return -EINVAL; | |
79dfc695 MK |
4237 | |
4238 | /* demote order must be smaller than hstate order */ | |
12658abf | 4239 | h = kobj_to_hstate(kobj, NULL); |
79dfc695 MK |
4240 | if (demote_order >= h->order) |
4241 | return -EINVAL; | |
4242 | ||
4243 | /* resize_lock synchronizes access to demote size and writes */ | |
4244 | mutex_lock(&h->resize_lock); | |
4245 | h->demote_order = demote_order; | |
4246 | mutex_unlock(&h->resize_lock); | |
4247 | ||
4248 | return count; | |
4249 | } | |
4250 | HSTATE_ATTR(demote_size); | |
4251 | ||
a3437870 NA |
4252 | static struct attribute *hstate_attrs[] = { |
4253 | &nr_hugepages_attr.attr, | |
4254 | &nr_overcommit_hugepages_attr.attr, | |
4255 | &free_hugepages_attr.attr, | |
4256 | &resv_hugepages_attr.attr, | |
4257 | &surplus_hugepages_attr.attr, | |
06808b08 LS |
4258 | #ifdef CONFIG_NUMA |
4259 | &nr_hugepages_mempolicy_attr.attr, | |
4260 | #endif | |
a3437870 NA |
4261 | NULL, |
4262 | }; | |
4263 | ||
67e5ed96 | 4264 | static const struct attribute_group hstate_attr_group = { |
a3437870 NA |
4265 | .attrs = hstate_attrs, |
4266 | }; | |
4267 | ||
79dfc695 MK |
4268 | static struct attribute *hstate_demote_attrs[] = { |
4269 | &demote_size_attr.attr, | |
4270 | &demote_attr.attr, | |
4271 | NULL, | |
4272 | }; | |
4273 | ||
4274 | static const struct attribute_group hstate_demote_attr_group = { | |
4275 | .attrs = hstate_demote_attrs, | |
4276 | }; | |
4277 | ||
094e9539 JM |
4278 | static int hugetlb_sysfs_add_hstate(struct hstate *h, struct kobject *parent, |
4279 | struct kobject **hstate_kobjs, | |
67e5ed96 | 4280 | const struct attribute_group *hstate_attr_group) |
a3437870 NA |
4281 | { |
4282 | int retval; | |
972dc4de | 4283 | int hi = hstate_index(h); |
a3437870 | 4284 | |
9a305230 LS |
4285 | hstate_kobjs[hi] = kobject_create_and_add(h->name, parent); |
4286 | if (!hstate_kobjs[hi]) | |
a3437870 NA |
4287 | return -ENOMEM; |
4288 | ||
9a305230 | 4289 | retval = sysfs_create_group(hstate_kobjs[hi], hstate_attr_group); |
cc2205a6 | 4290 | if (retval) { |
9a305230 | 4291 | kobject_put(hstate_kobjs[hi]); |
cc2205a6 | 4292 | hstate_kobjs[hi] = NULL; |
3a6bdda0 | 4293 | return retval; |
cc2205a6 | 4294 | } |
a3437870 | 4295 | |
79dfc695 | 4296 | if (h->demote_order) { |
01088a60 ML |
4297 | retval = sysfs_create_group(hstate_kobjs[hi], |
4298 | &hstate_demote_attr_group); | |
4299 | if (retval) { | |
79dfc695 | 4300 | pr_warn("HugeTLB unable to create demote interfaces for %s\n", h->name); |
01088a60 ML |
4301 | sysfs_remove_group(hstate_kobjs[hi], hstate_attr_group); |
4302 | kobject_put(hstate_kobjs[hi]); | |
4303 | hstate_kobjs[hi] = NULL; | |
4304 | return retval; | |
4305 | } | |
79dfc695 MK |
4306 | } |
4307 | ||
01088a60 | 4308 | return 0; |
a3437870 NA |
4309 | } |
4310 | ||
9a305230 | 4311 | #ifdef CONFIG_NUMA |
a4a00b45 | 4312 | static bool hugetlb_sysfs_initialized __ro_after_init; |
9a305230 LS |
4313 | |
4314 | /* | |
4315 | * node_hstate/s - associate per node hstate attributes, via their kobjects, | |
10fbcf4c KS |
4316 | * with node devices in node_devices[] using a parallel array. The array |
4317 | * index of a node device or _hstate == node id. | |
4318 | * This is here to avoid any static dependency of the node device driver, in | |
9a305230 LS |
4319 | * the base kernel, on the hugetlb module. |
4320 | */ | |
4321 | struct node_hstate { | |
4322 | struct kobject *hugepages_kobj; | |
4323 | struct kobject *hstate_kobjs[HUGE_MAX_HSTATE]; | |
4324 | }; | |
b4e289a6 | 4325 | static struct node_hstate node_hstates[MAX_NUMNODES]; |
9a305230 LS |
4326 | |
4327 | /* | |
10fbcf4c | 4328 | * A subset of global hstate attributes for node devices |
9a305230 LS |
4329 | */ |
4330 | static struct attribute *per_node_hstate_attrs[] = { | |
4331 | &nr_hugepages_attr.attr, | |
4332 | &free_hugepages_attr.attr, | |
4333 | &surplus_hugepages_attr.attr, | |
4334 | NULL, | |
4335 | }; | |
4336 | ||
67e5ed96 | 4337 | static const struct attribute_group per_node_hstate_attr_group = { |
9a305230 LS |
4338 | .attrs = per_node_hstate_attrs, |
4339 | }; | |
4340 | ||
4341 | /* | |
10fbcf4c | 4342 | * kobj_to_node_hstate - lookup global hstate for node device hstate attr kobj. |
9a305230 LS |
4343 | * Returns node id via non-NULL nidp. |
4344 | */ | |
4345 | static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) | |
4346 | { | |
4347 | int nid; | |
4348 | ||
4349 | for (nid = 0; nid < nr_node_ids; nid++) { | |
4350 | struct node_hstate *nhs = &node_hstates[nid]; | |
4351 | int i; | |
4352 | for (i = 0; i < HUGE_MAX_HSTATE; i++) | |
4353 | if (nhs->hstate_kobjs[i] == kobj) { | |
4354 | if (nidp) | |
4355 | *nidp = nid; | |
4356 | return &hstates[i]; | |
4357 | } | |
4358 | } | |
4359 | ||
4360 | BUG(); | |
4361 | return NULL; | |
4362 | } | |
4363 | ||
4364 | /* | |
10fbcf4c | 4365 | * Unregister hstate attributes from a single node device. |
9a305230 LS |
4366 | * No-op if no hstate attributes attached. |
4367 | */ | |
a4a00b45 | 4368 | void hugetlb_unregister_node(struct node *node) |
9a305230 LS |
4369 | { |
4370 | struct hstate *h; | |
10fbcf4c | 4371 | struct node_hstate *nhs = &node_hstates[node->dev.id]; |
9a305230 LS |
4372 | |
4373 | if (!nhs->hugepages_kobj) | |
9b5e5d0f | 4374 | return; /* no hstate attributes */ |
9a305230 | 4375 | |
972dc4de AK |
4376 | for_each_hstate(h) { |
4377 | int idx = hstate_index(h); | |
01088a60 ML |
4378 | struct kobject *hstate_kobj = nhs->hstate_kobjs[idx]; |
4379 | ||
4380 | if (!hstate_kobj) | |
4381 | continue; | |
4382 | if (h->demote_order) | |
4383 | sysfs_remove_group(hstate_kobj, &hstate_demote_attr_group); | |
4384 | sysfs_remove_group(hstate_kobj, &per_node_hstate_attr_group); | |
4385 | kobject_put(hstate_kobj); | |
4386 | nhs->hstate_kobjs[idx] = NULL; | |
972dc4de | 4387 | } |
9a305230 LS |
4388 | |
4389 | kobject_put(nhs->hugepages_kobj); | |
4390 | nhs->hugepages_kobj = NULL; | |
4391 | } | |
4392 | ||
9a305230 LS |
4393 | |
4394 | /* | |
10fbcf4c | 4395 | * Register hstate attributes for a single node device. |
9a305230 LS |
4396 | * No-op if attributes already registered. |
4397 | */ | |
a4a00b45 | 4398 | void hugetlb_register_node(struct node *node) |
9a305230 LS |
4399 | { |
4400 | struct hstate *h; | |
10fbcf4c | 4401 | struct node_hstate *nhs = &node_hstates[node->dev.id]; |
9a305230 LS |
4402 | int err; |
4403 | ||
a4a00b45 MS |
4404 | if (!hugetlb_sysfs_initialized) |
4405 | return; | |
4406 | ||
9a305230 LS |
4407 | if (nhs->hugepages_kobj) |
4408 | return; /* already allocated */ | |
4409 | ||
4410 | nhs->hugepages_kobj = kobject_create_and_add("hugepages", | |
10fbcf4c | 4411 | &node->dev.kobj); |
9a305230 LS |
4412 | if (!nhs->hugepages_kobj) |
4413 | return; | |
4414 | ||
4415 | for_each_hstate(h) { | |
4416 | err = hugetlb_sysfs_add_hstate(h, nhs->hugepages_kobj, | |
4417 | nhs->hstate_kobjs, | |
4418 | &per_node_hstate_attr_group); | |
4419 | if (err) { | |
282f4214 | 4420 | pr_err("HugeTLB: Unable to add hstate %s for node %d\n", |
ffb22af5 | 4421 | h->name, node->dev.id); |
9a305230 LS |
4422 | hugetlb_unregister_node(node); |
4423 | break; | |
4424 | } | |
4425 | } | |
4426 | } | |
4427 | ||
4428 | /* | |
9b5e5d0f | 4429 | * hugetlb init time: register hstate attributes for all registered node |
10fbcf4c KS |
4430 | * devices of nodes that have memory. All on-line nodes should have |
4431 | * registered their associated device by this time. | |
9a305230 | 4432 | */ |
7d9ca000 | 4433 | static void __init hugetlb_register_all_nodes(void) |
9a305230 LS |
4434 | { |
4435 | int nid; | |
4436 | ||
a4a00b45 | 4437 | for_each_online_node(nid) |
b958d4d0 | 4438 | hugetlb_register_node(node_devices[nid]); |
9a305230 LS |
4439 | } |
4440 | #else /* !CONFIG_NUMA */ | |
4441 | ||
4442 | static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) | |
4443 | { | |
4444 | BUG(); | |
4445 | if (nidp) | |
4446 | *nidp = -1; | |
4447 | return NULL; | |
4448 | } | |
4449 | ||
9a305230 LS |
4450 | static void hugetlb_register_all_nodes(void) { } |
4451 | ||
4452 | #endif | |
4453 | ||
263b8998 ML |
4454 | #ifdef CONFIG_CMA |
4455 | static void __init hugetlb_cma_check(void); | |
4456 | #else | |
4457 | static inline __init void hugetlb_cma_check(void) | |
4458 | { | |
4459 | } | |
4460 | #endif | |
4461 | ||
a4a00b45 MS |
4462 | static void __init hugetlb_sysfs_init(void) |
4463 | { | |
4464 | struct hstate *h; | |
4465 | int err; | |
4466 | ||
4467 | hugepages_kobj = kobject_create_and_add("hugepages", mm_kobj); | |
4468 | if (!hugepages_kobj) | |
4469 | return; | |
4470 | ||
4471 | for_each_hstate(h) { | |
4472 | err = hugetlb_sysfs_add_hstate(h, hugepages_kobj, | |
4473 | hstate_kobjs, &hstate_attr_group); | |
4474 | if (err) | |
4475 | pr_err("HugeTLB: Unable to add hstate %s", h->name); | |
4476 | } | |
4477 | ||
4478 | #ifdef CONFIG_NUMA | |
4479 | hugetlb_sysfs_initialized = true; | |
4480 | #endif | |
4481 | hugetlb_register_all_nodes(); | |
4482 | } | |
4483 | ||
962de548 KW |
4484 | #ifdef CONFIG_SYSCTL |
4485 | static void hugetlb_sysctl_init(void); | |
4486 | #else | |
4487 | static inline void hugetlb_sysctl_init(void) { } | |
4488 | #endif | |
4489 | ||
a3437870 NA |
4490 | static int __init hugetlb_init(void) |
4491 | { | |
8382d914 DB |
4492 | int i; |
4493 | ||
d6995da3 MK |
4494 | BUILD_BUG_ON(sizeof_field(struct page, private) * BITS_PER_BYTE < |
4495 | __NR_HPAGEFLAGS); | |
4496 | ||
c2833a5b MK |
4497 | if (!hugepages_supported()) { |
4498 | if (hugetlb_max_hstate || default_hstate_max_huge_pages) | |
4499 | pr_warn("HugeTLB: huge pages not supported, ignoring associated command-line parameters\n"); | |
0ef89d25 | 4500 | return 0; |
c2833a5b | 4501 | } |
a3437870 | 4502 | |
282f4214 MK |
4503 | /* |
4504 | * Make sure HPAGE_SIZE (HUGETLB_PAGE_ORDER) hstate exists. Some | |
4505 | * architectures depend on setup being done here. | |
4506 | */ | |
4507 | hugetlb_add_hstate(HUGETLB_PAGE_ORDER); | |
4508 | if (!parsed_default_hugepagesz) { | |
4509 | /* | |
4510 | * If we did not parse a default huge page size, set | |
4511 | * default_hstate_idx to HPAGE_SIZE hstate. And, if the | |
4512 | * number of huge pages for this default size was implicitly | |
4513 | * specified, set that here as well. | |
4514 | * Note that the implicit setting will overwrite an explicit | |
4515 | * setting. A warning will be printed in this case. | |
4516 | */ | |
4517 | default_hstate_idx = hstate_index(size_to_hstate(HPAGE_SIZE)); | |
4518 | if (default_hstate_max_huge_pages) { | |
4519 | if (default_hstate.max_huge_pages) { | |
4520 | char buf[32]; | |
4521 | ||
4522 | string_get_size(huge_page_size(&default_hstate), | |
4523 | 1, STRING_UNITS_2, buf, 32); | |
4524 | pr_warn("HugeTLB: Ignoring hugepages=%lu associated with %s page size\n", | |
4525 | default_hstate.max_huge_pages, buf); | |
4526 | pr_warn("HugeTLB: Using hugepages=%lu for number of default huge pages\n", | |
4527 | default_hstate_max_huge_pages); | |
4528 | } | |
4529 | default_hstate.max_huge_pages = | |
4530 | default_hstate_max_huge_pages; | |
b5389086 | 4531 | |
0a7a0f6f | 4532 | for_each_online_node(i) |
b5389086 ZY |
4533 | default_hstate.max_huge_pages_node[i] = |
4534 | default_hugepages_in_node[i]; | |
d715cf80 | 4535 | } |
f8b74815 | 4536 | } |
a3437870 | 4537 | |
cf11e85f | 4538 | hugetlb_cma_check(); |
a3437870 | 4539 | hugetlb_init_hstates(); |
aa888a74 | 4540 | gather_bootmem_prealloc(); |
a3437870 NA |
4541 | report_hugepages(); |
4542 | ||
4543 | hugetlb_sysfs_init(); | |
7179e7bf | 4544 | hugetlb_cgroup_file_init(); |
962de548 | 4545 | hugetlb_sysctl_init(); |
9a305230 | 4546 | |
8382d914 DB |
4547 | #ifdef CONFIG_SMP |
4548 | num_fault_mutexes = roundup_pow_of_two(8 * num_possible_cpus()); | |
4549 | #else | |
4550 | num_fault_mutexes = 1; | |
4551 | #endif | |
c672c7f2 | 4552 | hugetlb_fault_mutex_table = |
6da2ec56 KC |
4553 | kmalloc_array(num_fault_mutexes, sizeof(struct mutex), |
4554 | GFP_KERNEL); | |
c672c7f2 | 4555 | BUG_ON(!hugetlb_fault_mutex_table); |
8382d914 DB |
4556 | |
4557 | for (i = 0; i < num_fault_mutexes; i++) | |
c672c7f2 | 4558 | mutex_init(&hugetlb_fault_mutex_table[i]); |
a3437870 NA |
4559 | return 0; |
4560 | } | |
3e89e1c5 | 4561 | subsys_initcall(hugetlb_init); |
a3437870 | 4562 | |
ae94da89 MK |
4563 | /* Overwritten by architectures with more huge page sizes */ |
4564 | bool __init __attribute((weak)) arch_hugetlb_valid_size(unsigned long size) | |
9fee021d | 4565 | { |
ae94da89 | 4566 | return size == HPAGE_SIZE; |
9fee021d VT |
4567 | } |
4568 | ||
d00181b9 | 4569 | void __init hugetlb_add_hstate(unsigned int order) |
a3437870 NA |
4570 | { |
4571 | struct hstate *h; | |
8faa8b07 AK |
4572 | unsigned long i; |
4573 | ||
a3437870 | 4574 | if (size_to_hstate(PAGE_SIZE << order)) { |
a3437870 NA |
4575 | return; |
4576 | } | |
47d38344 | 4577 | BUG_ON(hugetlb_max_hstate >= HUGE_MAX_HSTATE); |
59838b25 | 4578 | BUG_ON(order < order_base_2(__NR_USED_SUBPAGE)); |
47d38344 | 4579 | h = &hstates[hugetlb_max_hstate++]; |
29383967 | 4580 | mutex_init(&h->resize_lock); |
a3437870 | 4581 | h->order = order; |
aca78307 | 4582 | h->mask = ~(huge_page_size(h) - 1); |
8faa8b07 AK |
4583 | for (i = 0; i < MAX_NUMNODES; ++i) |
4584 | INIT_LIST_HEAD(&h->hugepage_freelists[i]); | |
0edaecfa | 4585 | INIT_LIST_HEAD(&h->hugepage_activelist); |
54f18d35 AM |
4586 | h->next_nid_to_alloc = first_memory_node; |
4587 | h->next_nid_to_free = first_memory_node; | |
a3437870 | 4588 | snprintf(h->name, HSTATE_NAME_LEN, "hugepages-%lukB", |
c2c3a60a | 4589 | huge_page_size(h)/SZ_1K); |
8faa8b07 | 4590 | |
a3437870 NA |
4591 | parsed_hstate = h; |
4592 | } | |
4593 | ||
b5389086 ZY |
4594 | bool __init __weak hugetlb_node_alloc_supported(void) |
4595 | { | |
4596 | return true; | |
4597 | } | |
f87442f4 PL |
4598 | |
4599 | static void __init hugepages_clear_pages_in_node(void) | |
4600 | { | |
4601 | if (!hugetlb_max_hstate) { | |
4602 | default_hstate_max_huge_pages = 0; | |
4603 | memset(default_hugepages_in_node, 0, | |
10395680 | 4604 | sizeof(default_hugepages_in_node)); |
f87442f4 PL |
4605 | } else { |
4606 | parsed_hstate->max_huge_pages = 0; | |
4607 | memset(parsed_hstate->max_huge_pages_node, 0, | |
10395680 | 4608 | sizeof(parsed_hstate->max_huge_pages_node)); |
f87442f4 PL |
4609 | } |
4610 | } | |
4611 | ||
282f4214 MK |
4612 | /* |
4613 | * hugepages command line processing | |
4614 | * hugepages normally follows a valid hugepagsz or default_hugepagsz | |
4615 | * specification. If not, ignore the hugepages value. hugepages can also | |
4616 | * be the first huge page command line option in which case it implicitly | |
4617 | * specifies the number of huge pages for the default size. | |
4618 | */ | |
4619 | static int __init hugepages_setup(char *s) | |
a3437870 NA |
4620 | { |
4621 | unsigned long *mhp; | |
8faa8b07 | 4622 | static unsigned long *last_mhp; |
b5389086 ZY |
4623 | int node = NUMA_NO_NODE; |
4624 | int count; | |
4625 | unsigned long tmp; | |
4626 | char *p = s; | |
a3437870 | 4627 | |
9fee021d | 4628 | if (!parsed_valid_hugepagesz) { |
282f4214 | 4629 | pr_warn("HugeTLB: hugepages=%s does not follow a valid hugepagesz, ignoring\n", s); |
9fee021d | 4630 | parsed_valid_hugepagesz = true; |
f81f6e4b | 4631 | return 1; |
9fee021d | 4632 | } |
282f4214 | 4633 | |
a3437870 | 4634 | /* |
282f4214 MK |
4635 | * !hugetlb_max_hstate means we haven't parsed a hugepagesz= parameter |
4636 | * yet, so this hugepages= parameter goes to the "default hstate". | |
4637 | * Otherwise, it goes with the previously parsed hugepagesz or | |
4638 | * default_hugepagesz. | |
a3437870 | 4639 | */ |
9fee021d | 4640 | else if (!hugetlb_max_hstate) |
a3437870 NA |
4641 | mhp = &default_hstate_max_huge_pages; |
4642 | else | |
4643 | mhp = &parsed_hstate->max_huge_pages; | |
4644 | ||
8faa8b07 | 4645 | if (mhp == last_mhp) { |
282f4214 | 4646 | pr_warn("HugeTLB: hugepages= specified twice without interleaving hugepagesz=, ignoring hugepages=%s\n", s); |
f81f6e4b | 4647 | return 1; |
8faa8b07 AK |
4648 | } |
4649 | ||
b5389086 ZY |
4650 | while (*p) { |
4651 | count = 0; | |
4652 | if (sscanf(p, "%lu%n", &tmp, &count) != 1) | |
4653 | goto invalid; | |
4654 | /* Parameter is node format */ | |
4655 | if (p[count] == ':') { | |
4656 | if (!hugetlb_node_alloc_supported()) { | |
4657 | pr_warn("HugeTLB: architecture can't support node specific alloc, ignoring!\n"); | |
f81f6e4b | 4658 | return 1; |
b5389086 | 4659 | } |
0a7a0f6f | 4660 | if (tmp >= MAX_NUMNODES || !node_online(tmp)) |
e79ce983 | 4661 | goto invalid; |
0a7a0f6f | 4662 | node = array_index_nospec(tmp, MAX_NUMNODES); |
b5389086 | 4663 | p += count + 1; |
b5389086 ZY |
4664 | /* Parse hugepages */ |
4665 | if (sscanf(p, "%lu%n", &tmp, &count) != 1) | |
4666 | goto invalid; | |
4667 | if (!hugetlb_max_hstate) | |
4668 | default_hugepages_in_node[node] = tmp; | |
4669 | else | |
4670 | parsed_hstate->max_huge_pages_node[node] = tmp; | |
4671 | *mhp += tmp; | |
4672 | /* Go to parse next node*/ | |
4673 | if (p[count] == ',') | |
4674 | p += count + 1; | |
4675 | else | |
4676 | break; | |
4677 | } else { | |
4678 | if (p != s) | |
4679 | goto invalid; | |
4680 | *mhp = tmp; | |
4681 | break; | |
4682 | } | |
4683 | } | |
a3437870 | 4684 | |
8faa8b07 AK |
4685 | /* |
4686 | * Global state is always initialized later in hugetlb_init. | |
04adbc3f | 4687 | * But we need to allocate gigantic hstates here early to still |
8faa8b07 AK |
4688 | * use the bootmem allocator. |
4689 | */ | |
04adbc3f | 4690 | if (hugetlb_max_hstate && hstate_is_gigantic(parsed_hstate)) |
8faa8b07 AK |
4691 | hugetlb_hstate_alloc_pages(parsed_hstate); |
4692 | ||
4693 | last_mhp = mhp; | |
4694 | ||
a3437870 | 4695 | return 1; |
b5389086 ZY |
4696 | |
4697 | invalid: | |
4698 | pr_warn("HugeTLB: Invalid hugepages parameter %s\n", p); | |
f87442f4 | 4699 | hugepages_clear_pages_in_node(); |
f81f6e4b | 4700 | return 1; |
a3437870 | 4701 | } |
282f4214 | 4702 | __setup("hugepages=", hugepages_setup); |
e11bfbfc | 4703 | |
282f4214 MK |
4704 | /* |
4705 | * hugepagesz command line processing | |
4706 | * A specific huge page size can only be specified once with hugepagesz. | |
4707 | * hugepagesz is followed by hugepages on the command line. The global | |
4708 | * variable 'parsed_valid_hugepagesz' is used to determine if prior | |
4709 | * hugepagesz argument was valid. | |
4710 | */ | |
359f2544 | 4711 | static int __init hugepagesz_setup(char *s) |
e11bfbfc | 4712 | { |
359f2544 | 4713 | unsigned long size; |
282f4214 MK |
4714 | struct hstate *h; |
4715 | ||
4716 | parsed_valid_hugepagesz = false; | |
359f2544 MK |
4717 | size = (unsigned long)memparse(s, NULL); |
4718 | ||
4719 | if (!arch_hugetlb_valid_size(size)) { | |
282f4214 | 4720 | pr_err("HugeTLB: unsupported hugepagesz=%s\n", s); |
f81f6e4b | 4721 | return 1; |
359f2544 MK |
4722 | } |
4723 | ||
282f4214 MK |
4724 | h = size_to_hstate(size); |
4725 | if (h) { | |
4726 | /* | |
4727 | * hstate for this size already exists. This is normally | |
4728 | * an error, but is allowed if the existing hstate is the | |
4729 | * default hstate. More specifically, it is only allowed if | |
4730 | * the number of huge pages for the default hstate was not | |
4731 | * previously specified. | |
4732 | */ | |
4733 | if (!parsed_default_hugepagesz || h != &default_hstate || | |
4734 | default_hstate.max_huge_pages) { | |
4735 | pr_warn("HugeTLB: hugepagesz=%s specified twice, ignoring\n", s); | |
f81f6e4b | 4736 | return 1; |
282f4214 MK |
4737 | } |
4738 | ||
4739 | /* | |
4740 | * No need to call hugetlb_add_hstate() as hstate already | |
4741 | * exists. But, do set parsed_hstate so that a following | |
4742 | * hugepages= parameter will be applied to this hstate. | |
4743 | */ | |
4744 | parsed_hstate = h; | |
4745 | parsed_valid_hugepagesz = true; | |
4746 | return 1; | |
38237830 MK |
4747 | } |
4748 | ||
359f2544 | 4749 | hugetlb_add_hstate(ilog2(size) - PAGE_SHIFT); |
282f4214 | 4750 | parsed_valid_hugepagesz = true; |
e11bfbfc NP |
4751 | return 1; |
4752 | } | |
359f2544 MK |
4753 | __setup("hugepagesz=", hugepagesz_setup); |
4754 | ||
282f4214 MK |
4755 | /* |
4756 | * default_hugepagesz command line input | |
4757 | * Only one instance of default_hugepagesz allowed on command line. | |
4758 | */ | |
ae94da89 | 4759 | static int __init default_hugepagesz_setup(char *s) |
e11bfbfc | 4760 | { |
ae94da89 | 4761 | unsigned long size; |
b5389086 | 4762 | int i; |
ae94da89 | 4763 | |
282f4214 | 4764 | parsed_valid_hugepagesz = false; |
282f4214 MK |
4765 | if (parsed_default_hugepagesz) { |
4766 | pr_err("HugeTLB: default_hugepagesz previously specified, ignoring %s\n", s); | |
f81f6e4b | 4767 | return 1; |
282f4214 MK |
4768 | } |
4769 | ||
ae94da89 MK |
4770 | size = (unsigned long)memparse(s, NULL); |
4771 | ||
4772 | if (!arch_hugetlb_valid_size(size)) { | |
282f4214 | 4773 | pr_err("HugeTLB: unsupported default_hugepagesz=%s\n", s); |
f81f6e4b | 4774 | return 1; |
ae94da89 MK |
4775 | } |
4776 | ||
282f4214 MK |
4777 | hugetlb_add_hstate(ilog2(size) - PAGE_SHIFT); |
4778 | parsed_valid_hugepagesz = true; | |
4779 | parsed_default_hugepagesz = true; | |
4780 | default_hstate_idx = hstate_index(size_to_hstate(size)); | |
4781 | ||
4782 | /* | |
4783 | * The number of default huge pages (for this size) could have been | |
4784 | * specified as the first hugetlb parameter: hugepages=X. If so, | |
4785 | * then default_hstate_max_huge_pages is set. If the default huge | |
23baf831 | 4786 | * page size is gigantic (> MAX_ORDER), then the pages must be |
282f4214 MK |
4787 | * allocated here from bootmem allocator. |
4788 | */ | |
4789 | if (default_hstate_max_huge_pages) { | |
4790 | default_hstate.max_huge_pages = default_hstate_max_huge_pages; | |
0a7a0f6f | 4791 | for_each_online_node(i) |
b5389086 ZY |
4792 | default_hstate.max_huge_pages_node[i] = |
4793 | default_hugepages_in_node[i]; | |
282f4214 MK |
4794 | if (hstate_is_gigantic(&default_hstate)) |
4795 | hugetlb_hstate_alloc_pages(&default_hstate); | |
4796 | default_hstate_max_huge_pages = 0; | |
4797 | } | |
4798 | ||
e11bfbfc NP |
4799 | return 1; |
4800 | } | |
ae94da89 | 4801 | __setup("default_hugepagesz=", default_hugepagesz_setup); |
a3437870 | 4802 | |
d2226ebd FT |
4803 | static nodemask_t *policy_mbind_nodemask(gfp_t gfp) |
4804 | { | |
4805 | #ifdef CONFIG_NUMA | |
4806 | struct mempolicy *mpol = get_task_policy(current); | |
4807 | ||
4808 | /* | |
4809 | * Only enforce MPOL_BIND policy which overlaps with cpuset policy | |
4810 | * (from policy_nodemask) specifically for hugetlb case | |
4811 | */ | |
4812 | if (mpol->mode == MPOL_BIND && | |
4813 | (apply_policy_zone(mpol, gfp_zone(gfp)) && | |
4814 | cpuset_nodemask_valid_mems_allowed(&mpol->nodes))) | |
4815 | return &mpol->nodes; | |
4816 | #endif | |
4817 | return NULL; | |
4818 | } | |
4819 | ||
8ca39e68 | 4820 | static unsigned int allowed_mems_nr(struct hstate *h) |
8a213460 NA |
4821 | { |
4822 | int node; | |
4823 | unsigned int nr = 0; | |
d2226ebd | 4824 | nodemask_t *mbind_nodemask; |
8ca39e68 MS |
4825 | unsigned int *array = h->free_huge_pages_node; |
4826 | gfp_t gfp_mask = htlb_alloc_mask(h); | |
4827 | ||
d2226ebd | 4828 | mbind_nodemask = policy_mbind_nodemask(gfp_mask); |
8ca39e68 | 4829 | for_each_node_mask(node, cpuset_current_mems_allowed) { |
d2226ebd | 4830 | if (!mbind_nodemask || node_isset(node, *mbind_nodemask)) |
8ca39e68 MS |
4831 | nr += array[node]; |
4832 | } | |
8a213460 NA |
4833 | |
4834 | return nr; | |
4835 | } | |
4836 | ||
4837 | #ifdef CONFIG_SYSCTL | |
17743798 MS |
4838 | static int proc_hugetlb_doulongvec_minmax(struct ctl_table *table, int write, |
4839 | void *buffer, size_t *length, | |
4840 | loff_t *ppos, unsigned long *out) | |
4841 | { | |
4842 | struct ctl_table dup_table; | |
4843 | ||
4844 | /* | |
4845 | * In order to avoid races with __do_proc_doulongvec_minmax(), we | |
4846 | * can duplicate the @table and alter the duplicate of it. | |
4847 | */ | |
4848 | dup_table = *table; | |
4849 | dup_table.data = out; | |
4850 | ||
4851 | return proc_doulongvec_minmax(&dup_table, write, buffer, length, ppos); | |
4852 | } | |
4853 | ||
06808b08 LS |
4854 | static int hugetlb_sysctl_handler_common(bool obey_mempolicy, |
4855 | struct ctl_table *table, int write, | |
32927393 | 4856 | void *buffer, size_t *length, loff_t *ppos) |
1da177e4 | 4857 | { |
e5ff2159 | 4858 | struct hstate *h = &default_hstate; |
238d3c13 | 4859 | unsigned long tmp = h->max_huge_pages; |
08d4a246 | 4860 | int ret; |
e5ff2159 | 4861 | |
457c1b27 | 4862 | if (!hugepages_supported()) |
86613628 | 4863 | return -EOPNOTSUPP; |
457c1b27 | 4864 | |
17743798 MS |
4865 | ret = proc_hugetlb_doulongvec_minmax(table, write, buffer, length, ppos, |
4866 | &tmp); | |
08d4a246 MH |
4867 | if (ret) |
4868 | goto out; | |
e5ff2159 | 4869 | |
238d3c13 DR |
4870 | if (write) |
4871 | ret = __nr_hugepages_store_common(obey_mempolicy, h, | |
4872 | NUMA_NO_NODE, tmp, *length); | |
08d4a246 MH |
4873 | out: |
4874 | return ret; | |
1da177e4 | 4875 | } |
396faf03 | 4876 | |
962de548 | 4877 | static int hugetlb_sysctl_handler(struct ctl_table *table, int write, |
32927393 | 4878 | void *buffer, size_t *length, loff_t *ppos) |
06808b08 LS |
4879 | { |
4880 | ||
4881 | return hugetlb_sysctl_handler_common(false, table, write, | |
4882 | buffer, length, ppos); | |
4883 | } | |
4884 | ||
4885 | #ifdef CONFIG_NUMA | |
962de548 | 4886 | static int hugetlb_mempolicy_sysctl_handler(struct ctl_table *table, int write, |
32927393 | 4887 | void *buffer, size_t *length, loff_t *ppos) |
06808b08 LS |
4888 | { |
4889 | return hugetlb_sysctl_handler_common(true, table, write, | |
4890 | buffer, length, ppos); | |
4891 | } | |
4892 | #endif /* CONFIG_NUMA */ | |
4893 | ||
962de548 | 4894 | static int hugetlb_overcommit_handler(struct ctl_table *table, int write, |
32927393 | 4895 | void *buffer, size_t *length, loff_t *ppos) |
a3d0c6aa | 4896 | { |
a5516438 | 4897 | struct hstate *h = &default_hstate; |
e5ff2159 | 4898 | unsigned long tmp; |
08d4a246 | 4899 | int ret; |
e5ff2159 | 4900 | |
457c1b27 | 4901 | if (!hugepages_supported()) |
86613628 | 4902 | return -EOPNOTSUPP; |
457c1b27 | 4903 | |
c033a93c | 4904 | tmp = h->nr_overcommit_huge_pages; |
e5ff2159 | 4905 | |
bae7f4ae | 4906 | if (write && hstate_is_gigantic(h)) |
adbe8726 EM |
4907 | return -EINVAL; |
4908 | ||
17743798 MS |
4909 | ret = proc_hugetlb_doulongvec_minmax(table, write, buffer, length, ppos, |
4910 | &tmp); | |
08d4a246 MH |
4911 | if (ret) |
4912 | goto out; | |
e5ff2159 AK |
4913 | |
4914 | if (write) { | |
db71ef79 | 4915 | spin_lock_irq(&hugetlb_lock); |
e5ff2159 | 4916 | h->nr_overcommit_huge_pages = tmp; |
db71ef79 | 4917 | spin_unlock_irq(&hugetlb_lock); |
e5ff2159 | 4918 | } |
08d4a246 MH |
4919 | out: |
4920 | return ret; | |
a3d0c6aa NA |
4921 | } |
4922 | ||
962de548 KW |
4923 | static struct ctl_table hugetlb_table[] = { |
4924 | { | |
4925 | .procname = "nr_hugepages", | |
4926 | .data = NULL, | |
4927 | .maxlen = sizeof(unsigned long), | |
4928 | .mode = 0644, | |
4929 | .proc_handler = hugetlb_sysctl_handler, | |
4930 | }, | |
4931 | #ifdef CONFIG_NUMA | |
4932 | { | |
4933 | .procname = "nr_hugepages_mempolicy", | |
4934 | .data = NULL, | |
4935 | .maxlen = sizeof(unsigned long), | |
4936 | .mode = 0644, | |
4937 | .proc_handler = &hugetlb_mempolicy_sysctl_handler, | |
4938 | }, | |
4939 | #endif | |
4940 | { | |
4941 | .procname = "hugetlb_shm_group", | |
4942 | .data = &sysctl_hugetlb_shm_group, | |
4943 | .maxlen = sizeof(gid_t), | |
4944 | .mode = 0644, | |
4945 | .proc_handler = proc_dointvec, | |
4946 | }, | |
4947 | { | |
4948 | .procname = "nr_overcommit_hugepages", | |
4949 | .data = NULL, | |
4950 | .maxlen = sizeof(unsigned long), | |
4951 | .mode = 0644, | |
4952 | .proc_handler = hugetlb_overcommit_handler, | |
4953 | }, | |
4954 | { } | |
4955 | }; | |
4956 | ||
4957 | static void hugetlb_sysctl_init(void) | |
4958 | { | |
4959 | register_sysctl_init("vm", hugetlb_table); | |
4960 | } | |
1da177e4 LT |
4961 | #endif /* CONFIG_SYSCTL */ |
4962 | ||
e1759c21 | 4963 | void hugetlb_report_meminfo(struct seq_file *m) |
1da177e4 | 4964 | { |
fcb2b0c5 RG |
4965 | struct hstate *h; |
4966 | unsigned long total = 0; | |
4967 | ||
457c1b27 NA |
4968 | if (!hugepages_supported()) |
4969 | return; | |
fcb2b0c5 RG |
4970 | |
4971 | for_each_hstate(h) { | |
4972 | unsigned long count = h->nr_huge_pages; | |
4973 | ||
aca78307 | 4974 | total += huge_page_size(h) * count; |
fcb2b0c5 RG |
4975 | |
4976 | if (h == &default_hstate) | |
4977 | seq_printf(m, | |
4978 | "HugePages_Total: %5lu\n" | |
4979 | "HugePages_Free: %5lu\n" | |
4980 | "HugePages_Rsvd: %5lu\n" | |
4981 | "HugePages_Surp: %5lu\n" | |
4982 | "Hugepagesize: %8lu kB\n", | |
4983 | count, | |
4984 | h->free_huge_pages, | |
4985 | h->resv_huge_pages, | |
4986 | h->surplus_huge_pages, | |
aca78307 | 4987 | huge_page_size(h) / SZ_1K); |
fcb2b0c5 RG |
4988 | } |
4989 | ||
aca78307 | 4990 | seq_printf(m, "Hugetlb: %8lu kB\n", total / SZ_1K); |
1da177e4 LT |
4991 | } |
4992 | ||
7981593b | 4993 | int hugetlb_report_node_meminfo(char *buf, int len, int nid) |
1da177e4 | 4994 | { |
a5516438 | 4995 | struct hstate *h = &default_hstate; |
7981593b | 4996 | |
457c1b27 NA |
4997 | if (!hugepages_supported()) |
4998 | return 0; | |
7981593b JP |
4999 | |
5000 | return sysfs_emit_at(buf, len, | |
5001 | "Node %d HugePages_Total: %5u\n" | |
5002 | "Node %d HugePages_Free: %5u\n" | |
5003 | "Node %d HugePages_Surp: %5u\n", | |
5004 | nid, h->nr_huge_pages_node[nid], | |
5005 | nid, h->free_huge_pages_node[nid], | |
5006 | nid, h->surplus_huge_pages_node[nid]); | |
1da177e4 LT |
5007 | } |
5008 | ||
dcadcf1c | 5009 | void hugetlb_show_meminfo_node(int nid) |
949f7ec5 DR |
5010 | { |
5011 | struct hstate *h; | |
949f7ec5 | 5012 | |
457c1b27 NA |
5013 | if (!hugepages_supported()) |
5014 | return; | |
5015 | ||
dcadcf1c GL |
5016 | for_each_hstate(h) |
5017 | printk("Node %d hugepages_total=%u hugepages_free=%u hugepages_surp=%u hugepages_size=%lukB\n", | |
5018 | nid, | |
5019 | h->nr_huge_pages_node[nid], | |
5020 | h->free_huge_pages_node[nid], | |
5021 | h->surplus_huge_pages_node[nid], | |
5022 | huge_page_size(h) / SZ_1K); | |
949f7ec5 DR |
5023 | } |
5024 | ||
5d317b2b NH |
5025 | void hugetlb_report_usage(struct seq_file *m, struct mm_struct *mm) |
5026 | { | |
5027 | seq_printf(m, "HugetlbPages:\t%8lu kB\n", | |
6c1aa2d3 | 5028 | K(atomic_long_read(&mm->hugetlb_usage))); |
5d317b2b NH |
5029 | } |
5030 | ||
1da177e4 LT |
5031 | /* Return the number pages of memory we physically have, in PAGE_SIZE units. */ |
5032 | unsigned long hugetlb_total_pages(void) | |
5033 | { | |
d0028588 WL |
5034 | struct hstate *h; |
5035 | unsigned long nr_total_pages = 0; | |
5036 | ||
5037 | for_each_hstate(h) | |
5038 | nr_total_pages += h->nr_huge_pages * pages_per_huge_page(h); | |
5039 | return nr_total_pages; | |
1da177e4 | 5040 | } |
1da177e4 | 5041 | |
a5516438 | 5042 | static int hugetlb_acct_memory(struct hstate *h, long delta) |
fc1b8a73 MG |
5043 | { |
5044 | int ret = -ENOMEM; | |
5045 | ||
0aa7f354 ML |
5046 | if (!delta) |
5047 | return 0; | |
5048 | ||
db71ef79 | 5049 | spin_lock_irq(&hugetlb_lock); |
fc1b8a73 MG |
5050 | /* |
5051 | * When cpuset is configured, it breaks the strict hugetlb page | |
5052 | * reservation as the accounting is done on a global variable. Such | |
5053 | * reservation is completely rubbish in the presence of cpuset because | |
5054 | * the reservation is not checked against page availability for the | |
5055 | * current cpuset. Application can still potentially OOM'ed by kernel | |
5056 | * with lack of free htlb page in cpuset that the task is in. | |
5057 | * Attempt to enforce strict accounting with cpuset is almost | |
5058 | * impossible (or too ugly) because cpuset is too fluid that | |
5059 | * task or memory node can be dynamically moved between cpusets. | |
5060 | * | |
5061 | * The change of semantics for shared hugetlb mapping with cpuset is | |
5062 | * undesirable. However, in order to preserve some of the semantics, | |
5063 | * we fall back to check against current free page availability as | |
5064 | * a best attempt and hopefully to minimize the impact of changing | |
5065 | * semantics that cpuset has. | |
8ca39e68 MS |
5066 | * |
5067 | * Apart from cpuset, we also have memory policy mechanism that | |
5068 | * also determines from which node the kernel will allocate memory | |
5069 | * in a NUMA system. So similar to cpuset, we also should consider | |
5070 | * the memory policy of the current task. Similar to the description | |
5071 | * above. | |
fc1b8a73 MG |
5072 | */ |
5073 | if (delta > 0) { | |
a5516438 | 5074 | if (gather_surplus_pages(h, delta) < 0) |
fc1b8a73 MG |
5075 | goto out; |
5076 | ||
8ca39e68 | 5077 | if (delta > allowed_mems_nr(h)) { |
a5516438 | 5078 | return_unused_surplus_pages(h, delta); |
fc1b8a73 MG |
5079 | goto out; |
5080 | } | |
5081 | } | |
5082 | ||
5083 | ret = 0; | |
5084 | if (delta < 0) | |
a5516438 | 5085 | return_unused_surplus_pages(h, (unsigned long) -delta); |
fc1b8a73 MG |
5086 | |
5087 | out: | |
db71ef79 | 5088 | spin_unlock_irq(&hugetlb_lock); |
fc1b8a73 MG |
5089 | return ret; |
5090 | } | |
5091 | ||
84afd99b AW |
5092 | static void hugetlb_vm_op_open(struct vm_area_struct *vma) |
5093 | { | |
f522c3ac | 5094 | struct resv_map *resv = vma_resv_map(vma); |
84afd99b AW |
5095 | |
5096 | /* | |
612b8a31 | 5097 | * HPAGE_RESV_OWNER indicates a private mapping. |
84afd99b AW |
5098 | * This new VMA should share its siblings reservation map if present. |
5099 | * The VMA will only ever have a valid reservation map pointer where | |
5100 | * it is being copied for another still existing VMA. As that VMA | |
25985edc | 5101 | * has a reference to the reservation map it cannot disappear until |
84afd99b AW |
5102 | * after this open call completes. It is therefore safe to take a |
5103 | * new reference here without additional locking. | |
5104 | */ | |
09a26e83 MK |
5105 | if (resv && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { |
5106 | resv_map_dup_hugetlb_cgroup_uncharge_info(resv); | |
f522c3ac | 5107 | kref_get(&resv->refs); |
09a26e83 | 5108 | } |
8d9bfb26 | 5109 | |
131a79b4 MK |
5110 | /* |
5111 | * vma_lock structure for sharable mappings is vma specific. | |
612b8a31 MK |
5112 | * Clear old pointer (if copied via vm_area_dup) and allocate |
5113 | * new structure. Before clearing, make sure vma_lock is not | |
5114 | * for this vma. | |
131a79b4 MK |
5115 | */ |
5116 | if (vma->vm_flags & VM_MAYSHARE) { | |
612b8a31 MK |
5117 | struct hugetlb_vma_lock *vma_lock = vma->vm_private_data; |
5118 | ||
5119 | if (vma_lock) { | |
5120 | if (vma_lock->vma != vma) { | |
5121 | vma->vm_private_data = NULL; | |
5122 | hugetlb_vma_lock_alloc(vma); | |
5123 | } else | |
5124 | pr_warn("HugeTLB: vma_lock already exists in %s.\n", __func__); | |
5125 | } else | |
5126 | hugetlb_vma_lock_alloc(vma); | |
131a79b4 | 5127 | } |
84afd99b AW |
5128 | } |
5129 | ||
a1e78772 MG |
5130 | static void hugetlb_vm_op_close(struct vm_area_struct *vma) |
5131 | { | |
a5516438 | 5132 | struct hstate *h = hstate_vma(vma); |
8d9bfb26 | 5133 | struct resv_map *resv; |
90481622 | 5134 | struct hugepage_subpool *spool = subpool_vma(vma); |
4e35f483 | 5135 | unsigned long reserve, start, end; |
1c5ecae3 | 5136 | long gbl_reserve; |
84afd99b | 5137 | |
8d9bfb26 MK |
5138 | hugetlb_vma_lock_free(vma); |
5139 | ||
5140 | resv = vma_resv_map(vma); | |
4e35f483 JK |
5141 | if (!resv || !is_vma_resv_set(vma, HPAGE_RESV_OWNER)) |
5142 | return; | |
84afd99b | 5143 | |
4e35f483 JK |
5144 | start = vma_hugecache_offset(h, vma, vma->vm_start); |
5145 | end = vma_hugecache_offset(h, vma, vma->vm_end); | |
84afd99b | 5146 | |
4e35f483 | 5147 | reserve = (end - start) - region_count(resv, start, end); |
e9fe92ae | 5148 | hugetlb_cgroup_uncharge_counter(resv, start, end); |
4e35f483 | 5149 | if (reserve) { |
1c5ecae3 MK |
5150 | /* |
5151 | * Decrement reserve counts. The global reserve count may be | |
5152 | * adjusted if the subpool has a minimum size. | |
5153 | */ | |
5154 | gbl_reserve = hugepage_subpool_put_pages(spool, reserve); | |
5155 | hugetlb_acct_memory(h, -gbl_reserve); | |
84afd99b | 5156 | } |
e9fe92ae MA |
5157 | |
5158 | kref_put(&resv->refs, resv_map_release); | |
a1e78772 MG |
5159 | } |
5160 | ||
31383c68 DW |
5161 | static int hugetlb_vm_op_split(struct vm_area_struct *vma, unsigned long addr) |
5162 | { | |
5163 | if (addr & ~(huge_page_mask(hstate_vma(vma)))) | |
5164 | return -EINVAL; | |
b30c14cd JH |
5165 | |
5166 | /* | |
5167 | * PMD sharing is only possible for PUD_SIZE-aligned address ranges | |
5168 | * in HugeTLB VMAs. If we will lose PUD_SIZE alignment due to this | |
5169 | * split, unshare PMDs in the PUD_SIZE interval surrounding addr now. | |
5170 | */ | |
5171 | if (addr & ~PUD_MASK) { | |
5172 | /* | |
5173 | * hugetlb_vm_op_split is called right before we attempt to | |
5174 | * split the VMA. We will need to unshare PMDs in the old and | |
5175 | * new VMAs, so let's unshare before we split. | |
5176 | */ | |
5177 | unsigned long floor = addr & PUD_MASK; | |
5178 | unsigned long ceil = floor + PUD_SIZE; | |
5179 | ||
5180 | if (floor >= vma->vm_start && ceil <= vma->vm_end) | |
5181 | hugetlb_unshare_pmds(vma, floor, ceil); | |
5182 | } | |
5183 | ||
31383c68 DW |
5184 | return 0; |
5185 | } | |
5186 | ||
05ea8860 DW |
5187 | static unsigned long hugetlb_vm_op_pagesize(struct vm_area_struct *vma) |
5188 | { | |
aca78307 | 5189 | return huge_page_size(hstate_vma(vma)); |
05ea8860 DW |
5190 | } |
5191 | ||
1da177e4 LT |
5192 | /* |
5193 | * We cannot handle pagefaults against hugetlb pages at all. They cause | |
5194 | * handle_mm_fault() to try to instantiate regular-sized pages in the | |
6c26d310 | 5195 | * hugepage VMA. do_page_fault() is supposed to trap this, so BUG is we get |
1da177e4 LT |
5196 | * this far. |
5197 | */ | |
b3ec9f33 | 5198 | static vm_fault_t hugetlb_vm_op_fault(struct vm_fault *vmf) |
1da177e4 LT |
5199 | { |
5200 | BUG(); | |
d0217ac0 | 5201 | return 0; |
1da177e4 LT |
5202 | } |
5203 | ||
eec3636a JC |
5204 | /* |
5205 | * When a new function is introduced to vm_operations_struct and added | |
5206 | * to hugetlb_vm_ops, please consider adding the function to shm_vm_ops. | |
5207 | * This is because under System V memory model, mappings created via | |
5208 | * shmget/shmat with "huge page" specified are backed by hugetlbfs files, | |
5209 | * their original vm_ops are overwritten with shm_vm_ops. | |
5210 | */ | |
f0f37e2f | 5211 | const struct vm_operations_struct hugetlb_vm_ops = { |
d0217ac0 | 5212 | .fault = hugetlb_vm_op_fault, |
84afd99b | 5213 | .open = hugetlb_vm_op_open, |
a1e78772 | 5214 | .close = hugetlb_vm_op_close, |
dd3b614f | 5215 | .may_split = hugetlb_vm_op_split, |
05ea8860 | 5216 | .pagesize = hugetlb_vm_op_pagesize, |
1da177e4 LT |
5217 | }; |
5218 | ||
1e8f889b DG |
5219 | static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page, |
5220 | int writable) | |
63551ae0 DG |
5221 | { |
5222 | pte_t entry; | |
79c1c594 | 5223 | unsigned int shift = huge_page_shift(hstate_vma(vma)); |
63551ae0 | 5224 | |
1e8f889b | 5225 | if (writable) { |
106c992a GS |
5226 | entry = huge_pte_mkwrite(huge_pte_mkdirty(mk_huge_pte(page, |
5227 | vma->vm_page_prot))); | |
63551ae0 | 5228 | } else { |
106c992a GS |
5229 | entry = huge_pte_wrprotect(mk_huge_pte(page, |
5230 | vma->vm_page_prot)); | |
63551ae0 DG |
5231 | } |
5232 | entry = pte_mkyoung(entry); | |
79c1c594 | 5233 | entry = arch_make_huge_pte(entry, shift, vma->vm_flags); |
63551ae0 DG |
5234 | |
5235 | return entry; | |
5236 | } | |
5237 | ||
1e8f889b DG |
5238 | static void set_huge_ptep_writable(struct vm_area_struct *vma, |
5239 | unsigned long address, pte_t *ptep) | |
5240 | { | |
5241 | pte_t entry; | |
5242 | ||
106c992a | 5243 | entry = huge_pte_mkwrite(huge_pte_mkdirty(huge_ptep_get(ptep))); |
32f84528 | 5244 | if (huge_ptep_set_access_flags(vma, address, ptep, entry, 1)) |
4b3073e1 | 5245 | update_mmu_cache(vma, address, ptep); |
1e8f889b DG |
5246 | } |
5247 | ||
d5ed7444 | 5248 | bool is_hugetlb_entry_migration(pte_t pte) |
4a705fef NH |
5249 | { |
5250 | swp_entry_t swp; | |
5251 | ||
5252 | if (huge_pte_none(pte) || pte_present(pte)) | |
d5ed7444 | 5253 | return false; |
4a705fef | 5254 | swp = pte_to_swp_entry(pte); |
d79d176a | 5255 | if (is_migration_entry(swp)) |
d5ed7444 | 5256 | return true; |
4a705fef | 5257 | else |
d5ed7444 | 5258 | return false; |
4a705fef NH |
5259 | } |
5260 | ||
52526ca7 | 5261 | bool is_hugetlb_entry_hwpoisoned(pte_t pte) |
4a705fef NH |
5262 | { |
5263 | swp_entry_t swp; | |
5264 | ||
5265 | if (huge_pte_none(pte) || pte_present(pte)) | |
3e5c3600 | 5266 | return false; |
4a705fef | 5267 | swp = pte_to_swp_entry(pte); |
d79d176a | 5268 | if (is_hwpoison_entry(swp)) |
3e5c3600 | 5269 | return true; |
4a705fef | 5270 | else |
3e5c3600 | 5271 | return false; |
4a705fef | 5272 | } |
1e8f889b | 5273 | |
4eae4efa | 5274 | static void |
ea4c353d | 5275 | hugetlb_install_folio(struct vm_area_struct *vma, pte_t *ptep, unsigned long addr, |
935d4f0c | 5276 | struct folio *new_folio, pte_t old, unsigned long sz) |
4eae4efa | 5277 | { |
5a2f8d22 PX |
5278 | pte_t newpte = make_huge_pte(vma, &new_folio->page, 1); |
5279 | ||
ea4c353d | 5280 | __folio_mark_uptodate(new_folio); |
d0ce0e47 | 5281 | hugepage_add_new_anon_rmap(new_folio, vma, addr); |
5a2f8d22 PX |
5282 | if (userfaultfd_wp(vma) && huge_pte_uffd_wp(old)) |
5283 | newpte = huge_pte_mkuffd_wp(newpte); | |
935d4f0c | 5284 | set_huge_pte_at(vma->vm_mm, addr, ptep, newpte, sz); |
4eae4efa | 5285 | hugetlb_count_add(pages_per_huge_page(hstate_vma(vma)), vma->vm_mm); |
ea4c353d | 5286 | folio_set_hugetlb_migratable(new_folio); |
4eae4efa PX |
5287 | } |
5288 | ||
63551ae0 | 5289 | int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, |
bc70fbf2 PX |
5290 | struct vm_area_struct *dst_vma, |
5291 | struct vm_area_struct *src_vma) | |
63551ae0 | 5292 | { |
3aa4ed80 | 5293 | pte_t *src_pte, *dst_pte, entry; |
ad27ce20 | 5294 | struct folio *pte_folio; |
1c59827d | 5295 | unsigned long addr; |
bc70fbf2 PX |
5296 | bool cow = is_cow_mapping(src_vma->vm_flags); |
5297 | struct hstate *h = hstate_vma(src_vma); | |
a5516438 | 5298 | unsigned long sz = huge_page_size(h); |
4eae4efa | 5299 | unsigned long npages = pages_per_huge_page(h); |
ac46d4f3 | 5300 | struct mmu_notifier_range range; |
e95a9851 | 5301 | unsigned long last_addr_mask; |
e8569dd2 | 5302 | int ret = 0; |
1e8f889b | 5303 | |
ac46d4f3 | 5304 | if (cow) { |
7d4a8be0 | 5305 | mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, src, |
bc70fbf2 PX |
5306 | src_vma->vm_start, |
5307 | src_vma->vm_end); | |
ac46d4f3 | 5308 | mmu_notifier_invalidate_range_start(&range); |
e727bfd5 | 5309 | vma_assert_write_locked(src_vma); |
623a1ddf | 5310 | raw_write_seqcount_begin(&src->write_protect_seq); |
40549ba8 MK |
5311 | } else { |
5312 | /* | |
5313 | * For shared mappings the vma lock must be held before | |
9c67a207 | 5314 | * calling hugetlb_walk() in the src vma. Otherwise, the |
40549ba8 MK |
5315 | * returned ptep could go away if part of a shared pmd and |
5316 | * another thread calls huge_pmd_unshare. | |
5317 | */ | |
5318 | hugetlb_vma_lock_read(src_vma); | |
ac46d4f3 | 5319 | } |
e8569dd2 | 5320 | |
e95a9851 | 5321 | last_addr_mask = hugetlb_mask_last_page(h); |
bc70fbf2 | 5322 | for (addr = src_vma->vm_start; addr < src_vma->vm_end; addr += sz) { |
cb900f41 | 5323 | spinlock_t *src_ptl, *dst_ptl; |
9c67a207 | 5324 | src_pte = hugetlb_walk(src_vma, addr, sz); |
e95a9851 MK |
5325 | if (!src_pte) { |
5326 | addr |= last_addr_mask; | |
c74df32c | 5327 | continue; |
e95a9851 | 5328 | } |
bc70fbf2 | 5329 | dst_pte = huge_pte_alloc(dst, dst_vma, addr, sz); |
e8569dd2 AS |
5330 | if (!dst_pte) { |
5331 | ret = -ENOMEM; | |
5332 | break; | |
5333 | } | |
c5c99429 | 5334 | |
5e41540c MK |
5335 | /* |
5336 | * If the pagetables are shared don't copy or take references. | |
5e41540c | 5337 | * |
3aa4ed80 | 5338 | * dst_pte == src_pte is the common case of src/dest sharing. |
5e41540c | 5339 | * However, src could have 'unshared' and dst shares with |
3aa4ed80 ML |
5340 | * another vma. So page_count of ptep page is checked instead |
5341 | * to reliably determine whether pte is shared. | |
5e41540c | 5342 | */ |
3aa4ed80 | 5343 | if (page_count(virt_to_page(dst_pte)) > 1) { |
e95a9851 | 5344 | addr |= last_addr_mask; |
c5c99429 | 5345 | continue; |
e95a9851 | 5346 | } |
c5c99429 | 5347 | |
cb900f41 KS |
5348 | dst_ptl = huge_pte_lock(h, dst, dst_pte); |
5349 | src_ptl = huge_pte_lockptr(h, src, src_pte); | |
5350 | spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING); | |
4a705fef | 5351 | entry = huge_ptep_get(src_pte); |
4eae4efa | 5352 | again: |
3aa4ed80 | 5353 | if (huge_pte_none(entry)) { |
5e41540c | 5354 | /* |
3aa4ed80 | 5355 | * Skip if src entry none. |
5e41540c | 5356 | */ |
4a705fef | 5357 | ; |
c2cb0dcc | 5358 | } else if (unlikely(is_hugetlb_entry_hwpoisoned(entry))) { |
5a2f8d22 | 5359 | if (!userfaultfd_wp(dst_vma)) |
c2cb0dcc | 5360 | entry = huge_pte_clear_uffd_wp(entry); |
935d4f0c | 5361 | set_huge_pte_at(dst, addr, dst_pte, entry, sz); |
c2cb0dcc | 5362 | } else if (unlikely(is_hugetlb_entry_migration(entry))) { |
4a705fef | 5363 | swp_entry_t swp_entry = pte_to_swp_entry(entry); |
5a2f8d22 | 5364 | bool uffd_wp = pte_swp_uffd_wp(entry); |
4a705fef | 5365 | |
6c287605 | 5366 | if (!is_readable_migration_entry(swp_entry) && cow) { |
4a705fef NH |
5367 | /* |
5368 | * COW mappings require pages in both | |
5369 | * parent and child to be set to read. | |
5370 | */ | |
4dd845b5 AP |
5371 | swp_entry = make_readable_migration_entry( |
5372 | swp_offset(swp_entry)); | |
4a705fef | 5373 | entry = swp_entry_to_pte(swp_entry); |
bc70fbf2 | 5374 | if (userfaultfd_wp(src_vma) && uffd_wp) |
5a2f8d22 | 5375 | entry = pte_swp_mkuffd_wp(entry); |
935d4f0c | 5376 | set_huge_pte_at(src, addr, src_pte, entry, sz); |
4a705fef | 5377 | } |
5a2f8d22 | 5378 | if (!userfaultfd_wp(dst_vma)) |
bc70fbf2 | 5379 | entry = huge_pte_clear_uffd_wp(entry); |
935d4f0c | 5380 | set_huge_pte_at(dst, addr, dst_pte, entry, sz); |
bc70fbf2 | 5381 | } else if (unlikely(is_pte_marker(entry))) { |
af19487f AR |
5382 | pte_marker marker = copy_pte_marker( |
5383 | pte_to_swp_entry(entry), dst_vma); | |
5384 | ||
5385 | if (marker) | |
5386 | set_huge_pte_at(dst, addr, dst_pte, | |
935d4f0c | 5387 | make_pte_marker(marker), sz); |
4a705fef | 5388 | } else { |
4eae4efa | 5389 | entry = huge_ptep_get(src_pte); |
ad27ce20 Z |
5390 | pte_folio = page_folio(pte_page(entry)); |
5391 | folio_get(pte_folio); | |
4eae4efa PX |
5392 | |
5393 | /* | |
fb3d824d DH |
5394 | * Failing to duplicate the anon rmap is a rare case |
5395 | * where we see pinned hugetlb pages while they're | |
5396 | * prone to COW. We need to do the COW earlier during | |
5397 | * fork. | |
4eae4efa PX |
5398 | * |
5399 | * When pre-allocating the page or copying data, we | |
5400 | * need to be without the pgtable locks since we could | |
5401 | * sleep during the process. | |
5402 | */ | |
ad27ce20 Z |
5403 | if (!folio_test_anon(pte_folio)) { |
5404 | page_dup_file_rmap(&pte_folio->page, true); | |
5405 | } else if (page_try_dup_anon_rmap(&pte_folio->page, | |
5406 | true, src_vma)) { | |
4eae4efa | 5407 | pte_t src_pte_old = entry; |
d0ce0e47 | 5408 | struct folio *new_folio; |
4eae4efa PX |
5409 | |
5410 | spin_unlock(src_ptl); | |
5411 | spin_unlock(dst_ptl); | |
5412 | /* Do not use reserve as it's private owned */ | |
d0ce0e47 SK |
5413 | new_folio = alloc_hugetlb_folio(dst_vma, addr, 1); |
5414 | if (IS_ERR(new_folio)) { | |
ad27ce20 | 5415 | folio_put(pte_folio); |
d0ce0e47 | 5416 | ret = PTR_ERR(new_folio); |
4eae4efa PX |
5417 | break; |
5418 | } | |
1cb9dc4b | 5419 | ret = copy_user_large_folio(new_folio, |
ad27ce20 Z |
5420 | pte_folio, |
5421 | addr, dst_vma); | |
5422 | folio_put(pte_folio); | |
1cb9dc4b LS |
5423 | if (ret) { |
5424 | folio_put(new_folio); | |
5425 | break; | |
5426 | } | |
4eae4efa | 5427 | |
d0ce0e47 | 5428 | /* Install the new hugetlb folio if src pte stable */ |
4eae4efa PX |
5429 | dst_ptl = huge_pte_lock(h, dst, dst_pte); |
5430 | src_ptl = huge_pte_lockptr(h, src, src_pte); | |
5431 | spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING); | |
5432 | entry = huge_ptep_get(src_pte); | |
5433 | if (!pte_same(src_pte_old, entry)) { | |
bc70fbf2 | 5434 | restore_reserve_on_error(h, dst_vma, addr, |
d2d7bb44 | 5435 | new_folio); |
d0ce0e47 | 5436 | folio_put(new_folio); |
3aa4ed80 | 5437 | /* huge_ptep of dst_pte won't change as in child */ |
4eae4efa PX |
5438 | goto again; |
5439 | } | |
5a2f8d22 | 5440 | hugetlb_install_folio(dst_vma, dst_pte, addr, |
935d4f0c | 5441 | new_folio, src_pte_old, sz); |
4eae4efa PX |
5442 | spin_unlock(src_ptl); |
5443 | spin_unlock(dst_ptl); | |
5444 | continue; | |
5445 | } | |
5446 | ||
34ee645e | 5447 | if (cow) { |
0f10851e JG |
5448 | /* |
5449 | * No need to notify as we are downgrading page | |
5450 | * table protection not changing it to point | |
5451 | * to a new page. | |
5452 | * | |
ee65728e | 5453 | * See Documentation/mm/mmu_notifier.rst |
0f10851e | 5454 | */ |
7f2e9525 | 5455 | huge_ptep_set_wrprotect(src, addr, src_pte); |
84894e1c | 5456 | entry = huge_pte_wrprotect(entry); |
34ee645e | 5457 | } |
4eae4efa | 5458 | |
5a2f8d22 PX |
5459 | if (!userfaultfd_wp(dst_vma)) |
5460 | entry = huge_pte_clear_uffd_wp(entry); | |
5461 | ||
935d4f0c | 5462 | set_huge_pte_at(dst, addr, dst_pte, entry, sz); |
4eae4efa | 5463 | hugetlb_count_add(npages, dst); |
1c59827d | 5464 | } |
cb900f41 KS |
5465 | spin_unlock(src_ptl); |
5466 | spin_unlock(dst_ptl); | |
63551ae0 | 5467 | } |
63551ae0 | 5468 | |
623a1ddf DH |
5469 | if (cow) { |
5470 | raw_write_seqcount_end(&src->write_protect_seq); | |
ac46d4f3 | 5471 | mmu_notifier_invalidate_range_end(&range); |
40549ba8 MK |
5472 | } else { |
5473 | hugetlb_vma_unlock_read(src_vma); | |
623a1ddf | 5474 | } |
e8569dd2 AS |
5475 | |
5476 | return ret; | |
63551ae0 DG |
5477 | } |
5478 | ||
550a7d60 | 5479 | static void move_huge_pte(struct vm_area_struct *vma, unsigned long old_addr, |
935d4f0c RR |
5480 | unsigned long new_addr, pte_t *src_pte, pte_t *dst_pte, |
5481 | unsigned long sz) | |
550a7d60 MA |
5482 | { |
5483 | struct hstate *h = hstate_vma(vma); | |
5484 | struct mm_struct *mm = vma->vm_mm; | |
550a7d60 | 5485 | spinlock_t *src_ptl, *dst_ptl; |
db110a99 | 5486 | pte_t pte; |
550a7d60 | 5487 | |
550a7d60 MA |
5488 | dst_ptl = huge_pte_lock(h, mm, dst_pte); |
5489 | src_ptl = huge_pte_lockptr(h, mm, src_pte); | |
5490 | ||
5491 | /* | |
5492 | * We don't have to worry about the ordering of src and dst ptlocks | |
8651a137 | 5493 | * because exclusive mmap_lock (or the i_mmap_lock) prevents deadlock. |
550a7d60 MA |
5494 | */ |
5495 | if (src_ptl != dst_ptl) | |
5496 | spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING); | |
5497 | ||
5498 | pte = huge_ptep_get_and_clear(mm, old_addr, src_pte); | |
935d4f0c | 5499 | set_huge_pte_at(mm, new_addr, dst_pte, pte, sz); |
550a7d60 MA |
5500 | |
5501 | if (src_ptl != dst_ptl) | |
5502 | spin_unlock(src_ptl); | |
5503 | spin_unlock(dst_ptl); | |
5504 | } | |
5505 | ||
5506 | int move_hugetlb_page_tables(struct vm_area_struct *vma, | |
5507 | struct vm_area_struct *new_vma, | |
5508 | unsigned long old_addr, unsigned long new_addr, | |
5509 | unsigned long len) | |
5510 | { | |
5511 | struct hstate *h = hstate_vma(vma); | |
5512 | struct address_space *mapping = vma->vm_file->f_mapping; | |
5513 | unsigned long sz = huge_page_size(h); | |
5514 | struct mm_struct *mm = vma->vm_mm; | |
5515 | unsigned long old_end = old_addr + len; | |
e95a9851 | 5516 | unsigned long last_addr_mask; |
550a7d60 MA |
5517 | pte_t *src_pte, *dst_pte; |
5518 | struct mmu_notifier_range range; | |
3d0b95cd | 5519 | bool shared_pmd = false; |
550a7d60 | 5520 | |
7d4a8be0 | 5521 | mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm, old_addr, |
550a7d60 MA |
5522 | old_end); |
5523 | adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end); | |
3d0b95cd BW |
5524 | /* |
5525 | * In case of shared PMDs, we should cover the maximum possible | |
5526 | * range. | |
5527 | */ | |
5528 | flush_cache_range(vma, range.start, range.end); | |
5529 | ||
550a7d60 | 5530 | mmu_notifier_invalidate_range_start(&range); |
e95a9851 | 5531 | last_addr_mask = hugetlb_mask_last_page(h); |
550a7d60 | 5532 | /* Prevent race with file truncation */ |
40549ba8 | 5533 | hugetlb_vma_lock_write(vma); |
550a7d60 MA |
5534 | i_mmap_lock_write(mapping); |
5535 | for (; old_addr < old_end; old_addr += sz, new_addr += sz) { | |
9c67a207 | 5536 | src_pte = hugetlb_walk(vma, old_addr, sz); |
e95a9851 MK |
5537 | if (!src_pte) { |
5538 | old_addr |= last_addr_mask; | |
5539 | new_addr |= last_addr_mask; | |
550a7d60 | 5540 | continue; |
e95a9851 | 5541 | } |
550a7d60 MA |
5542 | if (huge_pte_none(huge_ptep_get(src_pte))) |
5543 | continue; | |
5544 | ||
4ddb4d91 | 5545 | if (huge_pmd_unshare(mm, vma, old_addr, src_pte)) { |
3d0b95cd | 5546 | shared_pmd = true; |
4ddb4d91 MK |
5547 | old_addr |= last_addr_mask; |
5548 | new_addr |= last_addr_mask; | |
550a7d60 | 5549 | continue; |
3d0b95cd | 5550 | } |
550a7d60 MA |
5551 | |
5552 | dst_pte = huge_pte_alloc(mm, new_vma, new_addr, sz); | |
5553 | if (!dst_pte) | |
5554 | break; | |
5555 | ||
935d4f0c | 5556 | move_huge_pte(vma, old_addr, new_addr, src_pte, dst_pte, sz); |
550a7d60 | 5557 | } |
3d0b95cd BW |
5558 | |
5559 | if (shared_pmd) | |
f720b471 | 5560 | flush_hugetlb_tlb_range(vma, range.start, range.end); |
3d0b95cd | 5561 | else |
f720b471 | 5562 | flush_hugetlb_tlb_range(vma, old_end - len, old_end); |
550a7d60 | 5563 | mmu_notifier_invalidate_range_end(&range); |
13e4ad2c | 5564 | i_mmap_unlock_write(mapping); |
40549ba8 | 5565 | hugetlb_vma_unlock_write(vma); |
550a7d60 MA |
5566 | |
5567 | return len + old_addr - old_end; | |
5568 | } | |
5569 | ||
2820b0f0 RR |
5570 | void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, |
5571 | unsigned long start, unsigned long end, | |
5572 | struct page *ref_page, zap_flags_t zap_flags) | |
63551ae0 DG |
5573 | { |
5574 | struct mm_struct *mm = vma->vm_mm; | |
5575 | unsigned long address; | |
c7546f8f | 5576 | pte_t *ptep; |
63551ae0 | 5577 | pte_t pte; |
cb900f41 | 5578 | spinlock_t *ptl; |
63551ae0 | 5579 | struct page *page; |
a5516438 AK |
5580 | struct hstate *h = hstate_vma(vma); |
5581 | unsigned long sz = huge_page_size(h); | |
e95a9851 | 5582 | unsigned long last_addr_mask; |
a4a118f2 | 5583 | bool force_flush = false; |
a5516438 | 5584 | |
63551ae0 | 5585 | WARN_ON(!is_vm_hugetlb_page(vma)); |
a5516438 AK |
5586 | BUG_ON(start & ~huge_page_mask(h)); |
5587 | BUG_ON(end & ~huge_page_mask(h)); | |
63551ae0 | 5588 | |
07e32661 AK |
5589 | /* |
5590 | * This is a hugetlb vma, all the pte entries should point | |
5591 | * to huge page. | |
5592 | */ | |
ed6a7935 | 5593 | tlb_change_page_size(tlb, sz); |
24669e58 | 5594 | tlb_start_vma(tlb, vma); |
dff11abe | 5595 | |
e95a9851 | 5596 | last_addr_mask = hugetlb_mask_last_page(h); |
569f48b8 | 5597 | address = start; |
569f48b8 | 5598 | for (; address < end; address += sz) { |
9c67a207 | 5599 | ptep = hugetlb_walk(vma, address, sz); |
e95a9851 MK |
5600 | if (!ptep) { |
5601 | address |= last_addr_mask; | |
c7546f8f | 5602 | continue; |
e95a9851 | 5603 | } |
c7546f8f | 5604 | |
cb900f41 | 5605 | ptl = huge_pte_lock(h, mm, ptep); |
4ddb4d91 | 5606 | if (huge_pmd_unshare(mm, vma, address, ptep)) { |
31d49da5 | 5607 | spin_unlock(ptl); |
a4a118f2 NA |
5608 | tlb_flush_pmd_range(tlb, address & PUD_MASK, PUD_SIZE); |
5609 | force_flush = true; | |
4ddb4d91 | 5610 | address |= last_addr_mask; |
31d49da5 AK |
5611 | continue; |
5612 | } | |
39dde65c | 5613 | |
6629326b | 5614 | pte = huge_ptep_get(ptep); |
31d49da5 AK |
5615 | if (huge_pte_none(pte)) { |
5616 | spin_unlock(ptl); | |
5617 | continue; | |
5618 | } | |
6629326b HD |
5619 | |
5620 | /* | |
9fbc1f63 NH |
5621 | * Migrating hugepage or HWPoisoned hugepage is already |
5622 | * unmapped and its refcount is dropped, so just clear pte here. | |
6629326b | 5623 | */ |
9fbc1f63 | 5624 | if (unlikely(!pte_present(pte))) { |
05e90bd0 PX |
5625 | /* |
5626 | * If the pte was wr-protected by uffd-wp in any of the | |
5627 | * swap forms, meanwhile the caller does not want to | |
5628 | * drop the uffd-wp bit in this zap, then replace the | |
5629 | * pte with a marker. | |
5630 | */ | |
5631 | if (pte_swp_uffd_wp_any(pte) && | |
5632 | !(zap_flags & ZAP_FLAG_DROP_MARKER)) | |
5633 | set_huge_pte_at(mm, address, ptep, | |
935d4f0c RR |
5634 | make_pte_marker(PTE_MARKER_UFFD_WP), |
5635 | sz); | |
05e90bd0 PX |
5636 | else |
5637 | huge_pte_clear(mm, address, ptep, sz); | |
31d49da5 AK |
5638 | spin_unlock(ptl); |
5639 | continue; | |
8c4894c6 | 5640 | } |
6629326b HD |
5641 | |
5642 | page = pte_page(pte); | |
04f2cbe3 MG |
5643 | /* |
5644 | * If a reference page is supplied, it is because a specific | |
5645 | * page is being unmapped, not a range. Ensure the page we | |
5646 | * are about to unmap is the actual page of interest. | |
5647 | */ | |
5648 | if (ref_page) { | |
31d49da5 AK |
5649 | if (page != ref_page) { |
5650 | spin_unlock(ptl); | |
5651 | continue; | |
5652 | } | |
04f2cbe3 MG |
5653 | /* |
5654 | * Mark the VMA as having unmapped its page so that | |
5655 | * future faults in this VMA will fail rather than | |
5656 | * looking like data was lost | |
5657 | */ | |
5658 | set_vma_resv_flags(vma, HPAGE_RESV_UNMAPPED); | |
5659 | } | |
5660 | ||
c7546f8f | 5661 | pte = huge_ptep_get_and_clear(mm, address, ptep); |
b528e4b6 | 5662 | tlb_remove_huge_tlb_entry(h, tlb, ptep, address); |
106c992a | 5663 | if (huge_pte_dirty(pte)) |
6649a386 | 5664 | set_page_dirty(page); |
05e90bd0 PX |
5665 | /* Leave a uffd-wp pte marker if needed */ |
5666 | if (huge_pte_uffd_wp(pte) && | |
5667 | !(zap_flags & ZAP_FLAG_DROP_MARKER)) | |
5668 | set_huge_pte_at(mm, address, ptep, | |
935d4f0c RR |
5669 | make_pte_marker(PTE_MARKER_UFFD_WP), |
5670 | sz); | |
5d317b2b | 5671 | hugetlb_count_sub(pages_per_huge_page(h), mm); |
cea86fe2 | 5672 | page_remove_rmap(page, vma, true); |
31d49da5 | 5673 | |
cb900f41 | 5674 | spin_unlock(ptl); |
e77b0852 | 5675 | tlb_remove_page_size(tlb, page, huge_page_size(h)); |
31d49da5 AK |
5676 | /* |
5677 | * Bail out after unmapping reference page if supplied | |
5678 | */ | |
5679 | if (ref_page) | |
5680 | break; | |
fe1668ae | 5681 | } |
24669e58 | 5682 | tlb_end_vma(tlb, vma); |
a4a118f2 NA |
5683 | |
5684 | /* | |
5685 | * If we unshared PMDs, the TLB flush was not recorded in mmu_gather. We | |
5686 | * could defer the flush until now, since by holding i_mmap_rwsem we | |
5687 | * guaranteed that the last refernece would not be dropped. But we must | |
5688 | * do the flushing before we return, as otherwise i_mmap_rwsem will be | |
5689 | * dropped and the last reference to the shared PMDs page might be | |
5690 | * dropped as well. | |
5691 | * | |
5692 | * In theory we could defer the freeing of the PMD pages as well, but | |
5693 | * huge_pmd_unshare() relies on the exact page_count for the PMD page to | |
5694 | * detect sharing, so we cannot defer the release of the page either. | |
5695 | * Instead, do flush now. | |
5696 | */ | |
5697 | if (force_flush) | |
5698 | tlb_flush_mmu_tlbonly(tlb); | |
1da177e4 | 5699 | } |
63551ae0 | 5700 | |
2820b0f0 RR |
5701 | void __hugetlb_zap_begin(struct vm_area_struct *vma, |
5702 | unsigned long *start, unsigned long *end) | |
d833352a | 5703 | { |
2820b0f0 RR |
5704 | if (!vma->vm_file) /* hugetlbfs_file_mmap error */ |
5705 | return; | |
5706 | ||
5707 | adjust_range_if_pmd_sharing_possible(vma, start, end); | |
131a79b4 | 5708 | hugetlb_vma_lock_write(vma); |
2820b0f0 RR |
5709 | if (vma->vm_file) |
5710 | i_mmap_lock_write(vma->vm_file->f_mapping); | |
5711 | } | |
131a79b4 | 5712 | |
2820b0f0 RR |
5713 | void __hugetlb_zap_end(struct vm_area_struct *vma, |
5714 | struct zap_details *details) | |
5715 | { | |
5716 | zap_flags_t zap_flags = details ? details->zap_flags : 0; | |
131a79b4 | 5717 | |
2820b0f0 RR |
5718 | if (!vma->vm_file) /* hugetlbfs_file_mmap error */ |
5719 | return; | |
d833352a | 5720 | |
04ada095 MK |
5721 | if (zap_flags & ZAP_FLAG_UNMAP) { /* final unmap */ |
5722 | /* | |
5723 | * Unlock and free the vma lock before releasing i_mmap_rwsem. | |
5724 | * When the vma_lock is freed, this makes the vma ineligible | |
5725 | * for pmd sharing. And, i_mmap_rwsem is required to set up | |
5726 | * pmd sharing. This is important as page tables for this | |
5727 | * unmapped range will be asynchrously deleted. If the page | |
5728 | * tables are shared, there will be issues when accessed by | |
5729 | * someone else. | |
5730 | */ | |
5731 | __hugetlb_vma_unlock_write_free(vma); | |
04ada095 | 5732 | } else { |
04ada095 MK |
5733 | hugetlb_vma_unlock_write(vma); |
5734 | } | |
2820b0f0 RR |
5735 | |
5736 | if (vma->vm_file) | |
5737 | i_mmap_unlock_write(vma->vm_file->f_mapping); | |
d833352a MG |
5738 | } |
5739 | ||
502717f4 | 5740 | void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, |
05e90bd0 PX |
5741 | unsigned long end, struct page *ref_page, |
5742 | zap_flags_t zap_flags) | |
502717f4 | 5743 | { |
369258ce | 5744 | struct mmu_notifier_range range; |
24669e58 | 5745 | struct mmu_gather tlb; |
dff11abe | 5746 | |
7d4a8be0 | 5747 | mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma->vm_mm, |
369258ce MK |
5748 | start, end); |
5749 | adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end); | |
5750 | mmu_notifier_invalidate_range_start(&range); | |
a72afd87 | 5751 | tlb_gather_mmu(&tlb, vma->vm_mm); |
369258ce | 5752 | |
05e90bd0 | 5753 | __unmap_hugepage_range(&tlb, vma, start, end, ref_page, zap_flags); |
369258ce MK |
5754 | |
5755 | mmu_notifier_invalidate_range_end(&range); | |
ae8eba8b | 5756 | tlb_finish_mmu(&tlb); |
502717f4 CK |
5757 | } |
5758 | ||
04f2cbe3 MG |
5759 | /* |
5760 | * This is called when the original mapper is failing to COW a MAP_PRIVATE | |
578b7725 | 5761 | * mapping it owns the reserve page for. The intention is to unmap the page |
04f2cbe3 MG |
5762 | * from other VMAs and let the children be SIGKILLed if they are faulting the |
5763 | * same region. | |
5764 | */ | |
2f4612af DB |
5765 | static void unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma, |
5766 | struct page *page, unsigned long address) | |
04f2cbe3 | 5767 | { |
7526674d | 5768 | struct hstate *h = hstate_vma(vma); |
04f2cbe3 MG |
5769 | struct vm_area_struct *iter_vma; |
5770 | struct address_space *mapping; | |
04f2cbe3 MG |
5771 | pgoff_t pgoff; |
5772 | ||
5773 | /* | |
5774 | * vm_pgoff is in PAGE_SIZE units, hence the different calculation | |
5775 | * from page cache lookup which is in HPAGE_SIZE units. | |
5776 | */ | |
7526674d | 5777 | address = address & huge_page_mask(h); |
36e4f20a MH |
5778 | pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) + |
5779 | vma->vm_pgoff; | |
93c76a3d | 5780 | mapping = vma->vm_file->f_mapping; |
04f2cbe3 | 5781 | |
4eb2b1dc MG |
5782 | /* |
5783 | * Take the mapping lock for the duration of the table walk. As | |
5784 | * this mapping should be shared between all the VMAs, | |
5785 | * __unmap_hugepage_range() is called as the lock is already held | |
5786 | */ | |
83cde9e8 | 5787 | i_mmap_lock_write(mapping); |
6b2dbba8 | 5788 | vma_interval_tree_foreach(iter_vma, &mapping->i_mmap, pgoff, pgoff) { |
04f2cbe3 MG |
5789 | /* Do not unmap the current VMA */ |
5790 | if (iter_vma == vma) | |
5791 | continue; | |
5792 | ||
2f84a899 MG |
5793 | /* |
5794 | * Shared VMAs have their own reserves and do not affect | |
5795 | * MAP_PRIVATE accounting but it is possible that a shared | |
5796 | * VMA is using the same page so check and skip such VMAs. | |
5797 | */ | |
5798 | if (iter_vma->vm_flags & VM_MAYSHARE) | |
5799 | continue; | |
5800 | ||
04f2cbe3 MG |
5801 | /* |
5802 | * Unmap the page from other VMAs without their own reserves. | |
5803 | * They get marked to be SIGKILLed if they fault in these | |
5804 | * areas. This is because a future no-page fault on this VMA | |
5805 | * could insert a zeroed page instead of the data existing | |
5806 | * from the time of fork. This would look like data corruption | |
5807 | */ | |
5808 | if (!is_vma_resv_set(iter_vma, HPAGE_RESV_OWNER)) | |
24669e58 | 5809 | unmap_hugepage_range(iter_vma, address, |
05e90bd0 | 5810 | address + huge_page_size(h), page, 0); |
04f2cbe3 | 5811 | } |
83cde9e8 | 5812 | i_mmap_unlock_write(mapping); |
04f2cbe3 MG |
5813 | } |
5814 | ||
0fe6e20b | 5815 | /* |
c89357e2 | 5816 | * hugetlb_wp() should be called with page lock of the original hugepage held. |
aa6d2e8c | 5817 | * Called with hugetlb_fault_mutex_table held and pte_page locked so we |
ef009b25 MH |
5818 | * cannot race with other handlers or page migration. |
5819 | * Keep the pte_same checks anyway to make transition from the mutex easier. | |
0fe6e20b | 5820 | */ |
c89357e2 DH |
5821 | static vm_fault_t hugetlb_wp(struct mm_struct *mm, struct vm_area_struct *vma, |
5822 | unsigned long address, pte_t *ptep, unsigned int flags, | |
371607a3 | 5823 | struct folio *pagecache_folio, spinlock_t *ptl) |
1e8f889b | 5824 | { |
c89357e2 | 5825 | const bool unshare = flags & FAULT_FLAG_UNSHARE; |
60d5b473 | 5826 | pte_t pte = huge_ptep_get(ptep); |
a5516438 | 5827 | struct hstate *h = hstate_vma(vma); |
959a78b6 | 5828 | struct folio *old_folio; |
d0ce0e47 | 5829 | struct folio *new_folio; |
2b740303 SJ |
5830 | int outside_reserve = 0; |
5831 | vm_fault_t ret = 0; | |
974e6d66 | 5832 | unsigned long haddr = address & huge_page_mask(h); |
ac46d4f3 | 5833 | struct mmu_notifier_range range; |
1e8f889b | 5834 | |
60d5b473 PX |
5835 | /* |
5836 | * Never handle CoW for uffd-wp protected pages. It should be only | |
5837 | * handled when the uffd-wp protection is removed. | |
5838 | * | |
5839 | * Note that only the CoW optimization path (in hugetlb_no_page()) | |
5840 | * can trigger this, because hugetlb_fault() will always resolve | |
5841 | * uffd-wp bit first. | |
5842 | */ | |
5843 | if (!unshare && huge_pte_uffd_wp(pte)) | |
5844 | return 0; | |
5845 | ||
1d8d1464 DH |
5846 | /* |
5847 | * hugetlb does not support FOLL_FORCE-style write faults that keep the | |
5848 | * PTE mapped R/O such as maybe_mkwrite() would do. | |
5849 | */ | |
5850 | if (WARN_ON_ONCE(!unshare && !(vma->vm_flags & VM_WRITE))) | |
5851 | return VM_FAULT_SIGSEGV; | |
5852 | ||
5853 | /* Let's take out MAP_SHARED mappings first. */ | |
5854 | if (vma->vm_flags & VM_MAYSHARE) { | |
1d8d1464 DH |
5855 | set_huge_ptep_writable(vma, haddr, ptep); |
5856 | return 0; | |
5857 | } | |
5858 | ||
959a78b6 | 5859 | old_folio = page_folio(pte_page(pte)); |
1e8f889b | 5860 | |
662ce1dc YY |
5861 | delayacct_wpcopy_start(); |
5862 | ||
04f2cbe3 | 5863 | retry_avoidcopy: |
c89357e2 DH |
5864 | /* |
5865 | * If no-one else is actually using this page, we're the exclusive | |
5866 | * owner and can reuse this page. | |
5867 | */ | |
959a78b6 | 5868 | if (folio_mapcount(old_folio) == 1 && folio_test_anon(old_folio)) { |
5ca43289 | 5869 | if (!PageAnonExclusive(&old_folio->page)) { |
06968625 | 5870 | folio_move_anon_rmap(old_folio, vma); |
5ca43289 DH |
5871 | SetPageAnonExclusive(&old_folio->page); |
5872 | } | |
c89357e2 DH |
5873 | if (likely(!unshare)) |
5874 | set_huge_ptep_writable(vma, haddr, ptep); | |
662ce1dc YY |
5875 | |
5876 | delayacct_wpcopy_end(); | |
83c54070 | 5877 | return 0; |
1e8f889b | 5878 | } |
959a78b6 Z |
5879 | VM_BUG_ON_PAGE(folio_test_anon(old_folio) && |
5880 | PageAnonExclusive(&old_folio->page), &old_folio->page); | |
1e8f889b | 5881 | |
04f2cbe3 MG |
5882 | /* |
5883 | * If the process that created a MAP_PRIVATE mapping is about to | |
5884 | * perform a COW due to a shared page count, attempt to satisfy | |
5885 | * the allocation without using the existing reserves. The pagecache | |
5886 | * page is used to determine if the reserve at this address was | |
5887 | * consumed or not. If reserves were used, a partial faulted mapping | |
5888 | * at the time of fork() could consume its reserves on COW instead | |
5889 | * of the full address range. | |
5890 | */ | |
5944d011 | 5891 | if (is_vma_resv_set(vma, HPAGE_RESV_OWNER) && |
959a78b6 | 5892 | old_folio != pagecache_folio) |
04f2cbe3 MG |
5893 | outside_reserve = 1; |
5894 | ||
959a78b6 | 5895 | folio_get(old_folio); |
b76c8cfb | 5896 | |
ad4404a2 DB |
5897 | /* |
5898 | * Drop page table lock as buddy allocator may be called. It will | |
5899 | * be acquired again before returning to the caller, as expected. | |
5900 | */ | |
cb900f41 | 5901 | spin_unlock(ptl); |
d0ce0e47 | 5902 | new_folio = alloc_hugetlb_folio(vma, haddr, outside_reserve); |
1e8f889b | 5903 | |
d0ce0e47 | 5904 | if (IS_ERR(new_folio)) { |
04f2cbe3 MG |
5905 | /* |
5906 | * If a process owning a MAP_PRIVATE mapping fails to COW, | |
5907 | * it is due to references held by a child and an insufficient | |
5908 | * huge page pool. To guarantee the original mappers | |
5909 | * reliability, unmap the page from child processes. The child | |
5910 | * may get SIGKILLed if it later faults. | |
5911 | */ | |
5912 | if (outside_reserve) { | |
40549ba8 MK |
5913 | struct address_space *mapping = vma->vm_file->f_mapping; |
5914 | pgoff_t idx; | |
5915 | u32 hash; | |
5916 | ||
959a78b6 | 5917 | folio_put(old_folio); |
40549ba8 MK |
5918 | /* |
5919 | * Drop hugetlb_fault_mutex and vma_lock before | |
5920 | * unmapping. unmapping needs to hold vma_lock | |
5921 | * in write mode. Dropping vma_lock in read mode | |
5922 | * here is OK as COW mappings do not interact with | |
5923 | * PMD sharing. | |
5924 | * | |
5925 | * Reacquire both after unmap operation. | |
5926 | */ | |
5927 | idx = vma_hugecache_offset(h, vma, haddr); | |
5928 | hash = hugetlb_fault_mutex_hash(mapping, idx); | |
5929 | hugetlb_vma_unlock_read(vma); | |
5930 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); | |
5931 | ||
959a78b6 | 5932 | unmap_ref_private(mm, vma, &old_folio->page, haddr); |
40549ba8 MK |
5933 | |
5934 | mutex_lock(&hugetlb_fault_mutex_table[hash]); | |
5935 | hugetlb_vma_lock_read(vma); | |
2f4612af | 5936 | spin_lock(ptl); |
9c67a207 | 5937 | ptep = hugetlb_walk(vma, haddr, huge_page_size(h)); |
2f4612af DB |
5938 | if (likely(ptep && |
5939 | pte_same(huge_ptep_get(ptep), pte))) | |
5940 | goto retry_avoidcopy; | |
5941 | /* | |
5942 | * race occurs while re-acquiring page table | |
5943 | * lock, and our job is done. | |
5944 | */ | |
662ce1dc | 5945 | delayacct_wpcopy_end(); |
2f4612af | 5946 | return 0; |
04f2cbe3 MG |
5947 | } |
5948 | ||
d0ce0e47 | 5949 | ret = vmf_error(PTR_ERR(new_folio)); |
ad4404a2 | 5950 | goto out_release_old; |
1e8f889b DG |
5951 | } |
5952 | ||
0fe6e20b NH |
5953 | /* |
5954 | * When the original hugepage is shared one, it does not have | |
5955 | * anon_vma prepared. | |
5956 | */ | |
44e2aa93 | 5957 | if (unlikely(anon_vma_prepare(vma))) { |
ad4404a2 DB |
5958 | ret = VM_FAULT_OOM; |
5959 | goto out_release_all; | |
44e2aa93 | 5960 | } |
0fe6e20b | 5961 | |
959a78b6 | 5962 | if (copy_user_large_folio(new_folio, old_folio, address, vma)) { |
1cb9dc4b LS |
5963 | ret = VM_FAULT_HWPOISON_LARGE; |
5964 | goto out_release_all; | |
5965 | } | |
d0ce0e47 | 5966 | __folio_mark_uptodate(new_folio); |
1e8f889b | 5967 | |
7d4a8be0 | 5968 | mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm, haddr, |
6f4f13e8 | 5969 | haddr + huge_page_size(h)); |
ac46d4f3 | 5970 | mmu_notifier_invalidate_range_start(&range); |
ad4404a2 | 5971 | |
b76c8cfb | 5972 | /* |
cb900f41 | 5973 | * Retake the page table lock to check for racing updates |
b76c8cfb LW |
5974 | * before the page tables are altered |
5975 | */ | |
cb900f41 | 5976 | spin_lock(ptl); |
9c67a207 | 5977 | ptep = hugetlb_walk(vma, haddr, huge_page_size(h)); |
a9af0c5d | 5978 | if (likely(ptep && pte_same(huge_ptep_get(ptep), pte))) { |
0f230bc2 PX |
5979 | pte_t newpte = make_huge_pte(vma, &new_folio->page, !unshare); |
5980 | ||
c89357e2 | 5981 | /* Break COW or unshare */ |
5b7a1d40 | 5982 | huge_ptep_clear_flush(vma, haddr, ptep); |
959a78b6 | 5983 | page_remove_rmap(&old_folio->page, vma, true); |
d0ce0e47 | 5984 | hugepage_add_new_anon_rmap(new_folio, vma, haddr); |
0f230bc2 PX |
5985 | if (huge_pte_uffd_wp(pte)) |
5986 | newpte = huge_pte_mkuffd_wp(newpte); | |
935d4f0c | 5987 | set_huge_pte_at(mm, haddr, ptep, newpte, huge_page_size(h)); |
d0ce0e47 | 5988 | folio_set_hugetlb_migratable(new_folio); |
1e8f889b | 5989 | /* Make the old page be freed below */ |
959a78b6 | 5990 | new_folio = old_folio; |
1e8f889b | 5991 | } |
cb900f41 | 5992 | spin_unlock(ptl); |
ac46d4f3 | 5993 | mmu_notifier_invalidate_range_end(&range); |
ad4404a2 | 5994 | out_release_all: |
c89357e2 DH |
5995 | /* |
5996 | * No restore in case of successful pagetable update (Break COW or | |
5997 | * unshare) | |
5998 | */ | |
959a78b6 | 5999 | if (new_folio != old_folio) |
d2d7bb44 | 6000 | restore_reserve_on_error(h, vma, haddr, new_folio); |
d0ce0e47 | 6001 | folio_put(new_folio); |
ad4404a2 | 6002 | out_release_old: |
959a78b6 | 6003 | folio_put(old_folio); |
8312034f | 6004 | |
ad4404a2 | 6005 | spin_lock(ptl); /* Caller expects lock to be held */ |
662ce1dc YY |
6006 | |
6007 | delayacct_wpcopy_end(); | |
ad4404a2 | 6008 | return ret; |
1e8f889b DG |
6009 | } |
6010 | ||
3ae77f43 HD |
6011 | /* |
6012 | * Return whether there is a pagecache page to back given address within VMA. | |
3ae77f43 HD |
6013 | */ |
6014 | static bool hugetlbfs_pagecache_present(struct hstate *h, | |
2a15efc9 HD |
6015 | struct vm_area_struct *vma, unsigned long address) |
6016 | { | |
91a2fb95 | 6017 | struct address_space *mapping = vma->vm_file->f_mapping; |
a08c7193 | 6018 | pgoff_t idx = linear_page_index(vma, address); |
fd4aed8d | 6019 | struct folio *folio; |
2a15efc9 | 6020 | |
fd4aed8d MK |
6021 | folio = filemap_get_folio(mapping, idx); |
6022 | if (IS_ERR(folio)) | |
6023 | return false; | |
6024 | folio_put(folio); | |
6025 | return true; | |
2a15efc9 HD |
6026 | } |
6027 | ||
9b91c0e2 | 6028 | int hugetlb_add_to_page_cache(struct folio *folio, struct address_space *mapping, |
ab76ad54 MK |
6029 | pgoff_t idx) |
6030 | { | |
6031 | struct inode *inode = mapping->host; | |
6032 | struct hstate *h = hstate_inode(inode); | |
d9ef44de | 6033 | int err; |
ab76ad54 | 6034 | |
a08c7193 | 6035 | idx <<= huge_page_order(h); |
d9ef44de MWO |
6036 | __folio_set_locked(folio); |
6037 | err = __filemap_add_folio(mapping, folio, idx, GFP_KERNEL, NULL); | |
6038 | ||
6039 | if (unlikely(err)) { | |
6040 | __folio_clear_locked(folio); | |
ab76ad54 | 6041 | return err; |
d9ef44de | 6042 | } |
9b91c0e2 | 6043 | folio_clear_hugetlb_restore_reserve(folio); |
ab76ad54 | 6044 | |
22146c3c | 6045 | /* |
d9ef44de | 6046 | * mark folio dirty so that it will not be removed from cache/file |
22146c3c MK |
6047 | * by non-hugetlbfs specific code paths. |
6048 | */ | |
d9ef44de | 6049 | folio_mark_dirty(folio); |
22146c3c | 6050 | |
ab76ad54 MK |
6051 | spin_lock(&inode->i_lock); |
6052 | inode->i_blocks += blocks_per_huge_page(h); | |
6053 | spin_unlock(&inode->i_lock); | |
6054 | return 0; | |
6055 | } | |
6056 | ||
7677f7fd AR |
6057 | static inline vm_fault_t hugetlb_handle_userfault(struct vm_area_struct *vma, |
6058 | struct address_space *mapping, | |
6059 | pgoff_t idx, | |
6060 | unsigned int flags, | |
6061 | unsigned long haddr, | |
824ddc60 | 6062 | unsigned long addr, |
7677f7fd AR |
6063 | unsigned long reason) |
6064 | { | |
7677f7fd AR |
6065 | u32 hash; |
6066 | struct vm_fault vmf = { | |
6067 | .vma = vma, | |
6068 | .address = haddr, | |
824ddc60 | 6069 | .real_address = addr, |
7677f7fd AR |
6070 | .flags = flags, |
6071 | ||
6072 | /* | |
6073 | * Hard to debug if it ends up being | |
6074 | * used by a callee that assumes | |
6075 | * something about the other | |
6076 | * uninitialized fields... same as in | |
6077 | * memory.c | |
6078 | */ | |
6079 | }; | |
6080 | ||
6081 | /* | |
958f32ce LS |
6082 | * vma_lock and hugetlb_fault_mutex must be dropped before handling |
6083 | * userfault. Also mmap_lock could be dropped due to handling | |
6084 | * userfault, any vma operation should be careful from here. | |
7677f7fd | 6085 | */ |
40549ba8 | 6086 | hugetlb_vma_unlock_read(vma); |
7677f7fd AR |
6087 | hash = hugetlb_fault_mutex_hash(mapping, idx); |
6088 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); | |
958f32ce | 6089 | return handle_userfault(&vmf, reason); |
7677f7fd AR |
6090 | } |
6091 | ||
2ea7ff1e PX |
6092 | /* |
6093 | * Recheck pte with pgtable lock. Returns true if pte didn't change, or | |
6094 | * false if pte changed or is changing. | |
6095 | */ | |
6096 | static bool hugetlb_pte_stable(struct hstate *h, struct mm_struct *mm, | |
6097 | pte_t *ptep, pte_t old_pte) | |
6098 | { | |
6099 | spinlock_t *ptl; | |
6100 | bool same; | |
6101 | ||
6102 | ptl = huge_pte_lock(h, mm, ptep); | |
6103 | same = pte_same(huge_ptep_get(ptep), old_pte); | |
6104 | spin_unlock(ptl); | |
6105 | ||
6106 | return same; | |
6107 | } | |
6108 | ||
2b740303 SJ |
6109 | static vm_fault_t hugetlb_no_page(struct mm_struct *mm, |
6110 | struct vm_area_struct *vma, | |
6111 | struct address_space *mapping, pgoff_t idx, | |
c64e912c PX |
6112 | unsigned long address, pte_t *ptep, |
6113 | pte_t old_pte, unsigned int flags) | |
ac9b9c66 | 6114 | { |
a5516438 | 6115 | struct hstate *h = hstate_vma(vma); |
2b740303 | 6116 | vm_fault_t ret = VM_FAULT_SIGBUS; |
409eb8c2 | 6117 | int anon_rmap = 0; |
4c887265 | 6118 | unsigned long size; |
d0ce0e47 | 6119 | struct folio *folio; |
1e8f889b | 6120 | pte_t new_pte; |
cb900f41 | 6121 | spinlock_t *ptl; |
285b8dca | 6122 | unsigned long haddr = address & huge_page_mask(h); |
d0ce0e47 | 6123 | bool new_folio, new_pagecache_folio = false; |
958f32ce | 6124 | u32 hash = hugetlb_fault_mutex_hash(mapping, idx); |
4c887265 | 6125 | |
04f2cbe3 MG |
6126 | /* |
6127 | * Currently, we are forced to kill the process in the event the | |
6128 | * original mapper has unmapped pages from the child due to a failed | |
c89357e2 DH |
6129 | * COW/unsharing. Warn that such a situation has occurred as it may not |
6130 | * be obvious. | |
04f2cbe3 MG |
6131 | */ |
6132 | if (is_vma_resv_set(vma, HPAGE_RESV_UNMAPPED)) { | |
910154d5 | 6133 | pr_warn_ratelimited("PID %d killed due to inadequate hugepage pool\n", |
ffb22af5 | 6134 | current->pid); |
958f32ce | 6135 | goto out; |
04f2cbe3 MG |
6136 | } |
6137 | ||
4c887265 | 6138 | /* |
188a3972 MK |
6139 | * Use page lock to guard against racing truncation |
6140 | * before we get page_table_lock. | |
4c887265 | 6141 | */ |
d0ce0e47 | 6142 | new_folio = false; |
a08c7193 | 6143 | folio = filemap_lock_hugetlb_folio(h, mapping, idx); |
66dabbb6 | 6144 | if (IS_ERR(folio)) { |
188a3972 MK |
6145 | size = i_size_read(mapping->host) >> huge_page_shift(h); |
6146 | if (idx >= size) | |
6147 | goto out; | |
7677f7fd | 6148 | /* Check for page in userfault range */ |
2ea7ff1e PX |
6149 | if (userfaultfd_missing(vma)) { |
6150 | /* | |
6151 | * Since hugetlb_no_page() was examining pte | |
6152 | * without pgtable lock, we need to re-test under | |
6153 | * lock because the pte may not be stable and could | |
6154 | * have changed from under us. Try to detect | |
6155 | * either changed or during-changing ptes and retry | |
6156 | * properly when needed. | |
6157 | * | |
6158 | * Note that userfaultfd is actually fine with | |
6159 | * false positives (e.g. caused by pte changed), | |
6160 | * but not wrong logical events (e.g. caused by | |
6161 | * reading a pte during changing). The latter can | |
6162 | * confuse the userspace, so the strictness is very | |
6163 | * much preferred. E.g., MISSING event should | |
6164 | * never happen on the page after UFFDIO_COPY has | |
6165 | * correctly installed the page and returned. | |
6166 | */ | |
6167 | if (!hugetlb_pte_stable(h, mm, ptep, old_pte)) { | |
6168 | ret = 0; | |
6169 | goto out; | |
6170 | } | |
6171 | ||
6172 | return hugetlb_handle_userfault(vma, mapping, idx, flags, | |
6173 | haddr, address, | |
6174 | VM_UFFD_MISSING); | |
6175 | } | |
1a1aad8a | 6176 | |
d0ce0e47 SK |
6177 | folio = alloc_hugetlb_folio(vma, haddr, 0); |
6178 | if (IS_ERR(folio)) { | |
4643d67e MK |
6179 | /* |
6180 | * Returning error will result in faulting task being | |
6181 | * sent SIGBUS. The hugetlb fault mutex prevents two | |
6182 | * tasks from racing to fault in the same page which | |
6183 | * could result in false unable to allocate errors. | |
6184 | * Page migration does not take the fault mutex, but | |
6185 | * does a clear then write of pte's under page table | |
6186 | * lock. Page fault code could race with migration, | |
6187 | * notice the clear pte and try to allocate a page | |
6188 | * here. Before returning error, get ptl and make | |
6189 | * sure there really is no pte entry. | |
6190 | */ | |
f9bf6c03 | 6191 | if (hugetlb_pte_stable(h, mm, ptep, old_pte)) |
d0ce0e47 | 6192 | ret = vmf_error(PTR_ERR(folio)); |
f9bf6c03 PX |
6193 | else |
6194 | ret = 0; | |
6bda666a CL |
6195 | goto out; |
6196 | } | |
d0ce0e47 SK |
6197 | clear_huge_page(&folio->page, address, pages_per_huge_page(h)); |
6198 | __folio_mark_uptodate(folio); | |
6199 | new_folio = true; | |
ac9b9c66 | 6200 | |
f83a275d | 6201 | if (vma->vm_flags & VM_MAYSHARE) { |
9b91c0e2 | 6202 | int err = hugetlb_add_to_page_cache(folio, mapping, idx); |
6bda666a | 6203 | if (err) { |
3a5497a2 ML |
6204 | /* |
6205 | * err can't be -EEXIST which implies someone | |
6206 | * else consumed the reservation since hugetlb | |
6207 | * fault mutex is held when add a hugetlb page | |
6208 | * to the page cache. So it's safe to call | |
6209 | * restore_reserve_on_error() here. | |
6210 | */ | |
d2d7bb44 | 6211 | restore_reserve_on_error(h, vma, haddr, folio); |
d0ce0e47 | 6212 | folio_put(folio); |
6bda666a CL |
6213 | goto out; |
6214 | } | |
d0ce0e47 | 6215 | new_pagecache_folio = true; |
23be7468 | 6216 | } else { |
d0ce0e47 | 6217 | folio_lock(folio); |
0fe6e20b NH |
6218 | if (unlikely(anon_vma_prepare(vma))) { |
6219 | ret = VM_FAULT_OOM; | |
6220 | goto backout_unlocked; | |
6221 | } | |
409eb8c2 | 6222 | anon_rmap = 1; |
23be7468 | 6223 | } |
0fe6e20b | 6224 | } else { |
998b4382 NH |
6225 | /* |
6226 | * If memory error occurs between mmap() and fault, some process | |
6227 | * don't have hwpoisoned swap entry for errored virtual address. | |
6228 | * So we need to block hugepage fault by PG_hwpoison bit check. | |
6229 | */ | |
d0ce0e47 | 6230 | if (unlikely(folio_test_hwpoison(folio))) { |
0eb98f15 | 6231 | ret = VM_FAULT_HWPOISON_LARGE | |
972dc4de | 6232 | VM_FAULT_SET_HINDEX(hstate_index(h)); |
998b4382 NH |
6233 | goto backout_unlocked; |
6234 | } | |
7677f7fd AR |
6235 | |
6236 | /* Check for page in userfault range. */ | |
6237 | if (userfaultfd_minor(vma)) { | |
d0ce0e47 SK |
6238 | folio_unlock(folio); |
6239 | folio_put(folio); | |
2ea7ff1e PX |
6240 | /* See comment in userfaultfd_missing() block above */ |
6241 | if (!hugetlb_pte_stable(h, mm, ptep, old_pte)) { | |
6242 | ret = 0; | |
6243 | goto out; | |
6244 | } | |
6245 | return hugetlb_handle_userfault(vma, mapping, idx, flags, | |
6246 | haddr, address, | |
6247 | VM_UFFD_MINOR); | |
7677f7fd | 6248 | } |
6bda666a | 6249 | } |
1e8f889b | 6250 | |
57303d80 AW |
6251 | /* |
6252 | * If we are going to COW a private mapping later, we examine the | |
6253 | * pending reservations for this page now. This will ensure that | |
6254 | * any allocations necessary to record that reservation occur outside | |
6255 | * the spinlock. | |
6256 | */ | |
5e911373 | 6257 | if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) { |
285b8dca | 6258 | if (vma_needs_reservation(h, vma, haddr) < 0) { |
2b26736c AW |
6259 | ret = VM_FAULT_OOM; |
6260 | goto backout_unlocked; | |
6261 | } | |
5e911373 | 6262 | /* Just decrements count, does not deallocate */ |
285b8dca | 6263 | vma_end_reservation(h, vma, haddr); |
5e911373 | 6264 | } |
57303d80 | 6265 | |
8bea8052 | 6266 | ptl = huge_pte_lock(h, mm, ptep); |
83c54070 | 6267 | ret = 0; |
c64e912c PX |
6268 | /* If pte changed from under us, retry */ |
6269 | if (!pte_same(huge_ptep_get(ptep), old_pte)) | |
4c887265 AL |
6270 | goto backout; |
6271 | ||
4781593d | 6272 | if (anon_rmap) |
d0ce0e47 | 6273 | hugepage_add_new_anon_rmap(folio, vma, haddr); |
4781593d | 6274 | else |
d0ce0e47 SK |
6275 | page_dup_file_rmap(&folio->page, true); |
6276 | new_pte = make_huge_pte(vma, &folio->page, ((vma->vm_flags & VM_WRITE) | |
1e8f889b | 6277 | && (vma->vm_flags & VM_SHARED))); |
c64e912c PX |
6278 | /* |
6279 | * If this pte was previously wr-protected, keep it wr-protected even | |
6280 | * if populated. | |
6281 | */ | |
6282 | if (unlikely(pte_marker_uffd_wp(old_pte))) | |
f1eb1bac | 6283 | new_pte = huge_pte_mkuffd_wp(new_pte); |
935d4f0c | 6284 | set_huge_pte_at(mm, haddr, ptep, new_pte, huge_page_size(h)); |
1e8f889b | 6285 | |
5d317b2b | 6286 | hugetlb_count_add(pages_per_huge_page(h), mm); |
788c7df4 | 6287 | if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) { |
1e8f889b | 6288 | /* Optimization, do the COW without a second fault */ |
371607a3 | 6289 | ret = hugetlb_wp(mm, vma, address, ptep, flags, folio, ptl); |
1e8f889b DG |
6290 | } |
6291 | ||
cb900f41 | 6292 | spin_unlock(ptl); |
cb6acd01 MK |
6293 | |
6294 | /* | |
d0ce0e47 SK |
6295 | * Only set hugetlb_migratable in newly allocated pages. Existing pages |
6296 | * found in the pagecache may not have hugetlb_migratable if they have | |
8f251a3d | 6297 | * been isolated for migration. |
cb6acd01 | 6298 | */ |
d0ce0e47 SK |
6299 | if (new_folio) |
6300 | folio_set_hugetlb_migratable(folio); | |
cb6acd01 | 6301 | |
d0ce0e47 | 6302 | folio_unlock(folio); |
4c887265 | 6303 | out: |
958f32ce LS |
6304 | hugetlb_vma_unlock_read(vma); |
6305 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); | |
ac9b9c66 | 6306 | return ret; |
4c887265 AL |
6307 | |
6308 | backout: | |
cb900f41 | 6309 | spin_unlock(ptl); |
2b26736c | 6310 | backout_unlocked: |
d0ce0e47 | 6311 | if (new_folio && !new_pagecache_folio) |
d2d7bb44 | 6312 | restore_reserve_on_error(h, vma, haddr, folio); |
fa27759a | 6313 | |
d0ce0e47 SK |
6314 | folio_unlock(folio); |
6315 | folio_put(folio); | |
4c887265 | 6316 | goto out; |
ac9b9c66 HD |
6317 | } |
6318 | ||
8382d914 | 6319 | #ifdef CONFIG_SMP |
188b04a7 | 6320 | u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx) |
8382d914 DB |
6321 | { |
6322 | unsigned long key[2]; | |
6323 | u32 hash; | |
6324 | ||
1b426bac MK |
6325 | key[0] = (unsigned long) mapping; |
6326 | key[1] = idx; | |
8382d914 | 6327 | |
55254636 | 6328 | hash = jhash2((u32 *)&key, sizeof(key)/(sizeof(u32)), 0); |
8382d914 DB |
6329 | |
6330 | return hash & (num_fault_mutexes - 1); | |
6331 | } | |
6332 | #else | |
6333 | /* | |
6c26d310 | 6334 | * For uniprocessor systems we always use a single mutex, so just |
8382d914 DB |
6335 | * return 0 and avoid the hashing overhead. |
6336 | */ | |
188b04a7 | 6337 | u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx) |
8382d914 DB |
6338 | { |
6339 | return 0; | |
6340 | } | |
6341 | #endif | |
6342 | ||
2b740303 | 6343 | vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, |
788c7df4 | 6344 | unsigned long address, unsigned int flags) |
86e5216f | 6345 | { |
8382d914 | 6346 | pte_t *ptep, entry; |
cb900f41 | 6347 | spinlock_t *ptl; |
2b740303 | 6348 | vm_fault_t ret; |
8382d914 DB |
6349 | u32 hash; |
6350 | pgoff_t idx; | |
061e62e8 | 6351 | struct folio *folio = NULL; |
371607a3 | 6352 | struct folio *pagecache_folio = NULL; |
a5516438 | 6353 | struct hstate *h = hstate_vma(vma); |
8382d914 | 6354 | struct address_space *mapping; |
0f792cf9 | 6355 | int need_wait_lock = 0; |
285b8dca | 6356 | unsigned long haddr = address & huge_page_mask(h); |
86e5216f | 6357 | |
4ec31152 MWO |
6358 | /* TODO: Handle faults under the VMA lock */ |
6359 | if (flags & FAULT_FLAG_VMA_LOCK) { | |
6360 | vma_end_read(vma); | |
6361 | return VM_FAULT_RETRY; | |
6362 | } | |
6363 | ||
3935baa9 DG |
6364 | /* |
6365 | * Serialize hugepage allocation and instantiation, so that we don't | |
6366 | * get spurious allocation failures if two CPUs race to instantiate | |
6367 | * the same page in the page cache. | |
6368 | */ | |
40549ba8 MK |
6369 | mapping = vma->vm_file->f_mapping; |
6370 | idx = vma_hugecache_offset(h, vma, haddr); | |
188b04a7 | 6371 | hash = hugetlb_fault_mutex_hash(mapping, idx); |
c672c7f2 | 6372 | mutex_lock(&hugetlb_fault_mutex_table[hash]); |
8382d914 | 6373 | |
40549ba8 MK |
6374 | /* |
6375 | * Acquire vma lock before calling huge_pte_alloc and hold | |
6376 | * until finished with ptep. This prevents huge_pmd_unshare from | |
6377 | * being called elsewhere and making the ptep no longer valid. | |
40549ba8 MK |
6378 | */ |
6379 | hugetlb_vma_lock_read(vma); | |
6380 | ptep = huge_pte_alloc(mm, vma, haddr, huge_page_size(h)); | |
6381 | if (!ptep) { | |
6382 | hugetlb_vma_unlock_read(vma); | |
6383 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); | |
6384 | return VM_FAULT_OOM; | |
6385 | } | |
6386 | ||
7f2e9525 | 6387 | entry = huge_ptep_get(ptep); |
af19487f AR |
6388 | if (huge_pte_none_mostly(entry)) { |
6389 | if (is_pte_marker(entry)) { | |
6390 | pte_marker marker = | |
6391 | pte_marker_get(pte_to_swp_entry(entry)); | |
6392 | ||
6393 | if (marker & PTE_MARKER_POISONED) { | |
6394 | ret = VM_FAULT_HWPOISON_LARGE; | |
6395 | goto out_mutex; | |
6396 | } | |
6397 | } | |
6398 | ||
958f32ce | 6399 | /* |
af19487f AR |
6400 | * Other PTE markers should be handled the same way as none PTE. |
6401 | * | |
958f32ce LS |
6402 | * hugetlb_no_page will drop vma lock and hugetlb fault |
6403 | * mutex internally, which make us return immediately. | |
6404 | */ | |
6405 | return hugetlb_no_page(mm, vma, mapping, idx, address, ptep, | |
c64e912c | 6406 | entry, flags); |
af19487f | 6407 | } |
86e5216f | 6408 | |
83c54070 | 6409 | ret = 0; |
1e8f889b | 6410 | |
0f792cf9 NH |
6411 | /* |
6412 | * entry could be a migration/hwpoison entry at this point, so this | |
6413 | * check prevents the kernel from going below assuming that we have | |
7c8de358 EP |
6414 | * an active hugepage in pagecache. This goto expects the 2nd page |
6415 | * fault, and is_hugetlb_entry_(migration|hwpoisoned) check will | |
6416 | * properly handle it. | |
0f792cf9 | 6417 | */ |
fcd48540 PX |
6418 | if (!pte_present(entry)) { |
6419 | if (unlikely(is_hugetlb_entry_migration(entry))) { | |
6420 | /* | |
6421 | * Release the hugetlb fault lock now, but retain | |
6422 | * the vma lock, because it is needed to guard the | |
6423 | * huge_pte_lockptr() later in | |
6424 | * migration_entry_wait_huge(). The vma lock will | |
6425 | * be released there. | |
6426 | */ | |
6427 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); | |
6428 | migration_entry_wait_huge(vma, ptep); | |
6429 | return 0; | |
6430 | } else if (unlikely(is_hugetlb_entry_hwpoisoned(entry))) | |
6431 | ret = VM_FAULT_HWPOISON_LARGE | | |
6432 | VM_FAULT_SET_HINDEX(hstate_index(h)); | |
0f792cf9 | 6433 | goto out_mutex; |
fcd48540 | 6434 | } |
0f792cf9 | 6435 | |
57303d80 | 6436 | /* |
c89357e2 DH |
6437 | * If we are going to COW/unshare the mapping later, we examine the |
6438 | * pending reservations for this page now. This will ensure that any | |
57303d80 | 6439 | * allocations necessary to record that reservation occur outside the |
1d8d1464 DH |
6440 | * spinlock. Also lookup the pagecache page now as it is used to |
6441 | * determine if a reservation has been consumed. | |
57303d80 | 6442 | */ |
c89357e2 | 6443 | if ((flags & (FAULT_FLAG_WRITE|FAULT_FLAG_UNSHARE)) && |
1d8d1464 | 6444 | !(vma->vm_flags & VM_MAYSHARE) && !huge_pte_write(entry)) { |
285b8dca | 6445 | if (vma_needs_reservation(h, vma, haddr) < 0) { |
2b26736c | 6446 | ret = VM_FAULT_OOM; |
b4d1d99f | 6447 | goto out_mutex; |
2b26736c | 6448 | } |
5e911373 | 6449 | /* Just decrements count, does not deallocate */ |
285b8dca | 6450 | vma_end_reservation(h, vma, haddr); |
57303d80 | 6451 | |
a08c7193 | 6452 | pagecache_folio = filemap_lock_hugetlb_folio(h, mapping, idx); |
66dabbb6 CH |
6453 | if (IS_ERR(pagecache_folio)) |
6454 | pagecache_folio = NULL; | |
57303d80 AW |
6455 | } |
6456 | ||
0f792cf9 NH |
6457 | ptl = huge_pte_lock(h, mm, ptep); |
6458 | ||
c89357e2 | 6459 | /* Check for a racing update before calling hugetlb_wp() */ |
0f792cf9 NH |
6460 | if (unlikely(!pte_same(entry, huge_ptep_get(ptep)))) |
6461 | goto out_ptl; | |
6462 | ||
166f3ecc PX |
6463 | /* Handle userfault-wp first, before trying to lock more pages */ |
6464 | if (userfaultfd_wp(vma) && huge_pte_uffd_wp(huge_ptep_get(ptep)) && | |
6465 | (flags & FAULT_FLAG_WRITE) && !huge_pte_write(entry)) { | |
d61ea1cb PX |
6466 | if (!userfaultfd_wp_async(vma)) { |
6467 | struct vm_fault vmf = { | |
6468 | .vma = vma, | |
6469 | .address = haddr, | |
6470 | .real_address = address, | |
6471 | .flags = flags, | |
6472 | }; | |
166f3ecc | 6473 | |
d61ea1cb PX |
6474 | spin_unlock(ptl); |
6475 | if (pagecache_folio) { | |
6476 | folio_unlock(pagecache_folio); | |
6477 | folio_put(pagecache_folio); | |
6478 | } | |
6479 | hugetlb_vma_unlock_read(vma); | |
6480 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); | |
6481 | return handle_userfault(&vmf, VM_UFFD_WP); | |
166f3ecc | 6482 | } |
d61ea1cb PX |
6483 | |
6484 | entry = huge_pte_clear_uffd_wp(entry); | |
52526ca7 MUA |
6485 | set_huge_pte_at(mm, haddr, ptep, entry, |
6486 | huge_page_size(hstate_vma(vma))); | |
d61ea1cb | 6487 | /* Fallthrough to CoW */ |
166f3ecc PX |
6488 | } |
6489 | ||
56c9cfb1 | 6490 | /* |
c89357e2 | 6491 | * hugetlb_wp() requires page locks of pte_page(entry) and |
371607a3 | 6492 | * pagecache_folio, so here we need take the former one |
061e62e8 | 6493 | * when folio != pagecache_folio or !pagecache_folio. |
56c9cfb1 | 6494 | */ |
061e62e8 Z |
6495 | folio = page_folio(pte_page(entry)); |
6496 | if (folio != pagecache_folio) | |
6497 | if (!folio_trylock(folio)) { | |
0f792cf9 NH |
6498 | need_wait_lock = 1; |
6499 | goto out_ptl; | |
6500 | } | |
b4d1d99f | 6501 | |
061e62e8 | 6502 | folio_get(folio); |
b4d1d99f | 6503 | |
c89357e2 | 6504 | if (flags & (FAULT_FLAG_WRITE|FAULT_FLAG_UNSHARE)) { |
106c992a | 6505 | if (!huge_pte_write(entry)) { |
c89357e2 | 6506 | ret = hugetlb_wp(mm, vma, address, ptep, flags, |
371607a3 | 6507 | pagecache_folio, ptl); |
0f792cf9 | 6508 | goto out_put_page; |
c89357e2 DH |
6509 | } else if (likely(flags & FAULT_FLAG_WRITE)) { |
6510 | entry = huge_pte_mkdirty(entry); | |
b4d1d99f | 6511 | } |
b4d1d99f DG |
6512 | } |
6513 | entry = pte_mkyoung(entry); | |
285b8dca | 6514 | if (huge_ptep_set_access_flags(vma, haddr, ptep, entry, |
788c7df4 | 6515 | flags & FAULT_FLAG_WRITE)) |
285b8dca | 6516 | update_mmu_cache(vma, haddr, ptep); |
0f792cf9 | 6517 | out_put_page: |
061e62e8 Z |
6518 | if (folio != pagecache_folio) |
6519 | folio_unlock(folio); | |
6520 | folio_put(folio); | |
cb900f41 KS |
6521 | out_ptl: |
6522 | spin_unlock(ptl); | |
57303d80 | 6523 | |
371607a3 SK |
6524 | if (pagecache_folio) { |
6525 | folio_unlock(pagecache_folio); | |
6526 | folio_put(pagecache_folio); | |
57303d80 | 6527 | } |
b4d1d99f | 6528 | out_mutex: |
40549ba8 | 6529 | hugetlb_vma_unlock_read(vma); |
c672c7f2 | 6530 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); |
0f792cf9 NH |
6531 | /* |
6532 | * Generally it's safe to hold refcount during waiting page lock. But | |
6533 | * here we just wait to defer the next page fault to avoid busy loop and | |
6534 | * the page is not used after unlocked before returning from the current | |
6535 | * page fault. So we are safe from accessing freed page, even if we wait | |
6536 | * here without taking refcount. | |
6537 | */ | |
6538 | if (need_wait_lock) | |
061e62e8 | 6539 | folio_wait_locked(folio); |
1e8f889b | 6540 | return ret; |
86e5216f AL |
6541 | } |
6542 | ||
714c1891 | 6543 | #ifdef CONFIG_USERFAULTFD |
72e315f7 HD |
6544 | /* |
6545 | * Can probably be eliminated, but still used by hugetlb_mfill_atomic_pte(). | |
6546 | */ | |
6547 | static struct folio *alloc_hugetlb_folio_vma(struct hstate *h, | |
6548 | struct vm_area_struct *vma, unsigned long address) | |
6549 | { | |
6550 | struct mempolicy *mpol; | |
6551 | nodemask_t *nodemask; | |
6552 | struct folio *folio; | |
6553 | gfp_t gfp_mask; | |
6554 | int node; | |
6555 | ||
6556 | gfp_mask = htlb_alloc_mask(h); | |
6557 | node = huge_node(vma, address, gfp_mask, &mpol, &nodemask); | |
6558 | folio = alloc_hugetlb_folio_nodemask(h, node, nodemask, gfp_mask); | |
6559 | mpol_cond_put(mpol); | |
6560 | ||
6561 | return folio; | |
6562 | } | |
6563 | ||
8fb5debc | 6564 | /* |
a734991c AR |
6565 | * Used by userfaultfd UFFDIO_* ioctls. Based on userfaultfd's mfill_atomic_pte |
6566 | * with modifications for hugetlb pages. | |
8fb5debc | 6567 | */ |
61c50040 | 6568 | int hugetlb_mfill_atomic_pte(pte_t *dst_pte, |
a734991c AR |
6569 | struct vm_area_struct *dst_vma, |
6570 | unsigned long dst_addr, | |
6571 | unsigned long src_addr, | |
d9712937 | 6572 | uffd_flags_t flags, |
0169fd51 | 6573 | struct folio **foliop) |
8fb5debc | 6574 | { |
61c50040 | 6575 | struct mm_struct *dst_mm = dst_vma->vm_mm; |
d9712937 AR |
6576 | bool is_continue = uffd_flags_mode_is(flags, MFILL_ATOMIC_CONTINUE); |
6577 | bool wp_enabled = (flags & MFILL_ATOMIC_WP); | |
8cc5fcbb MA |
6578 | struct hstate *h = hstate_vma(dst_vma); |
6579 | struct address_space *mapping = dst_vma->vm_file->f_mapping; | |
6580 | pgoff_t idx = vma_hugecache_offset(h, dst_vma, dst_addr); | |
1e392147 | 6581 | unsigned long size; |
1c9e8def | 6582 | int vm_shared = dst_vma->vm_flags & VM_SHARED; |
8fb5debc MK |
6583 | pte_t _dst_pte; |
6584 | spinlock_t *ptl; | |
8cc5fcbb | 6585 | int ret = -ENOMEM; |
d0ce0e47 | 6586 | struct folio *folio; |
f6191471 | 6587 | int writable; |
d0ce0e47 | 6588 | bool folio_in_pagecache = false; |
8fb5debc | 6589 | |
8a13897f AR |
6590 | if (uffd_flags_mode_is(flags, MFILL_ATOMIC_POISON)) { |
6591 | ptl = huge_pte_lock(h, dst_mm, dst_pte); | |
6592 | ||
6593 | /* Don't overwrite any existing PTEs (even markers) */ | |
6594 | if (!huge_pte_none(huge_ptep_get(dst_pte))) { | |
6595 | spin_unlock(ptl); | |
6596 | return -EEXIST; | |
6597 | } | |
6598 | ||
6599 | _dst_pte = make_pte_marker(PTE_MARKER_POISONED); | |
935d4f0c RR |
6600 | set_huge_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte, |
6601 | huge_page_size(h)); | |
8a13897f AR |
6602 | |
6603 | /* No need to invalidate - it was non-present before */ | |
6604 | update_mmu_cache(dst_vma, dst_addr, dst_pte); | |
6605 | ||
6606 | spin_unlock(ptl); | |
6607 | return 0; | |
6608 | } | |
6609 | ||
f6191471 AR |
6610 | if (is_continue) { |
6611 | ret = -EFAULT; | |
a08c7193 | 6612 | folio = filemap_lock_hugetlb_folio(h, mapping, idx); |
66dabbb6 | 6613 | if (IS_ERR(folio)) |
f6191471 | 6614 | goto out; |
d0ce0e47 | 6615 | folio_in_pagecache = true; |
0169fd51 Z |
6616 | } else if (!*foliop) { |
6617 | /* If a folio already exists, then it's UFFDIO_COPY for | |
d84cf06e MA |
6618 | * a non-missing case. Return -EEXIST. |
6619 | */ | |
6620 | if (vm_shared && | |
6621 | hugetlbfs_pagecache_present(h, dst_vma, dst_addr)) { | |
6622 | ret = -EEXIST; | |
6623 | goto out; | |
6624 | } | |
6625 | ||
d0ce0e47 SK |
6626 | folio = alloc_hugetlb_folio(dst_vma, dst_addr, 0); |
6627 | if (IS_ERR(folio)) { | |
d84cf06e | 6628 | ret = -ENOMEM; |
8fb5debc | 6629 | goto out; |
d84cf06e | 6630 | } |
8fb5debc | 6631 | |
e87340ca Z |
6632 | ret = copy_folio_from_user(folio, (const void __user *) src_addr, |
6633 | false); | |
8fb5debc | 6634 | |
c1e8d7c6 | 6635 | /* fallback to copy_from_user outside mmap_lock */ |
8fb5debc | 6636 | if (unlikely(ret)) { |
9e368259 | 6637 | ret = -ENOENT; |
d0ce0e47 | 6638 | /* Free the allocated folio which may have |
8cc5fcbb MA |
6639 | * consumed a reservation. |
6640 | */ | |
d2d7bb44 | 6641 | restore_reserve_on_error(h, dst_vma, dst_addr, folio); |
d0ce0e47 | 6642 | folio_put(folio); |
8cc5fcbb | 6643 | |
d0ce0e47 | 6644 | /* Allocate a temporary folio to hold the copied |
8cc5fcbb MA |
6645 | * contents. |
6646 | */ | |
d0ce0e47 SK |
6647 | folio = alloc_hugetlb_folio_vma(h, dst_vma, dst_addr); |
6648 | if (!folio) { | |
8cc5fcbb MA |
6649 | ret = -ENOMEM; |
6650 | goto out; | |
6651 | } | |
0169fd51 Z |
6652 | *foliop = folio; |
6653 | /* Set the outparam foliop and return to the caller to | |
8cc5fcbb | 6654 | * copy the contents outside the lock. Don't free the |
0169fd51 | 6655 | * folio. |
8cc5fcbb | 6656 | */ |
8fb5debc MK |
6657 | goto out; |
6658 | } | |
6659 | } else { | |
8cc5fcbb MA |
6660 | if (vm_shared && |
6661 | hugetlbfs_pagecache_present(h, dst_vma, dst_addr)) { | |
0169fd51 | 6662 | folio_put(*foliop); |
8cc5fcbb | 6663 | ret = -EEXIST; |
0169fd51 | 6664 | *foliop = NULL; |
8cc5fcbb MA |
6665 | goto out; |
6666 | } | |
6667 | ||
d0ce0e47 SK |
6668 | folio = alloc_hugetlb_folio(dst_vma, dst_addr, 0); |
6669 | if (IS_ERR(folio)) { | |
0169fd51 | 6670 | folio_put(*foliop); |
8cc5fcbb | 6671 | ret = -ENOMEM; |
0169fd51 | 6672 | *foliop = NULL; |
8cc5fcbb MA |
6673 | goto out; |
6674 | } | |
1cb9dc4b | 6675 | ret = copy_user_large_folio(folio, *foliop, dst_addr, dst_vma); |
0169fd51 Z |
6676 | folio_put(*foliop); |
6677 | *foliop = NULL; | |
1cb9dc4b LS |
6678 | if (ret) { |
6679 | folio_put(folio); | |
8cc5fcbb MA |
6680 | goto out; |
6681 | } | |
8fb5debc MK |
6682 | } |
6683 | ||
6684 | /* | |
d0ce0e47 | 6685 | * The memory barrier inside __folio_mark_uptodate makes sure that |
8fb5debc MK |
6686 | * preceding stores to the page contents become visible before |
6687 | * the set_pte_at() write. | |
6688 | */ | |
d0ce0e47 | 6689 | __folio_mark_uptodate(folio); |
8fb5debc | 6690 | |
f6191471 AR |
6691 | /* Add shared, newly allocated pages to the page cache. */ |
6692 | if (vm_shared && !is_continue) { | |
1e392147 AA |
6693 | size = i_size_read(mapping->host) >> huge_page_shift(h); |
6694 | ret = -EFAULT; | |
6695 | if (idx >= size) | |
6696 | goto out_release_nounlock; | |
1c9e8def | 6697 | |
1e392147 AA |
6698 | /* |
6699 | * Serialization between remove_inode_hugepages() and | |
7e1813d4 | 6700 | * hugetlb_add_to_page_cache() below happens through the |
1e392147 AA |
6701 | * hugetlb_fault_mutex_table that here must be hold by |
6702 | * the caller. | |
6703 | */ | |
9b91c0e2 | 6704 | ret = hugetlb_add_to_page_cache(folio, mapping, idx); |
1c9e8def MK |
6705 | if (ret) |
6706 | goto out_release_nounlock; | |
d0ce0e47 | 6707 | folio_in_pagecache = true; |
1c9e8def MK |
6708 | } |
6709 | ||
bcc66543 | 6710 | ptl = huge_pte_lock(h, dst_mm, dst_pte); |
8fb5debc | 6711 | |
8625147c | 6712 | ret = -EIO; |
d0ce0e47 | 6713 | if (folio_test_hwpoison(folio)) |
8625147c JH |
6714 | goto out_release_unlock; |
6715 | ||
6041c691 PX |
6716 | /* |
6717 | * We allow to overwrite a pte marker: consider when both MISSING|WP | |
6718 | * registered, we firstly wr-protect a none pte which has no page cache | |
6719 | * page backing it, then access the page. | |
6720 | */ | |
fa27759a | 6721 | ret = -EEXIST; |
6041c691 | 6722 | if (!huge_pte_none_mostly(huge_ptep_get(dst_pte))) |
8fb5debc MK |
6723 | goto out_release_unlock; |
6724 | ||
d0ce0e47 SK |
6725 | if (folio_in_pagecache) |
6726 | page_dup_file_rmap(&folio->page, true); | |
4781593d | 6727 | else |
d0ce0e47 | 6728 | hugepage_add_new_anon_rmap(folio, dst_vma, dst_addr); |
8fb5debc | 6729 | |
6041c691 PX |
6730 | /* |
6731 | * For either: (1) CONTINUE on a non-shared VMA, or (2) UFFDIO_COPY | |
6732 | * with wp flag set, don't set pte write bit. | |
6733 | */ | |
d9712937 | 6734 | if (wp_enabled || (is_continue && !vm_shared)) |
f6191471 AR |
6735 | writable = 0; |
6736 | else | |
6737 | writable = dst_vma->vm_flags & VM_WRITE; | |
6738 | ||
d0ce0e47 | 6739 | _dst_pte = make_huge_pte(dst_vma, &folio->page, writable); |
6041c691 PX |
6740 | /* |
6741 | * Always mark UFFDIO_COPY page dirty; note that this may not be | |
6742 | * extremely important for hugetlbfs for now since swapping is not | |
6743 | * supported, but we should still be clear in that this page cannot be | |
6744 | * thrown away at will, even if write bit not set. | |
6745 | */ | |
6746 | _dst_pte = huge_pte_mkdirty(_dst_pte); | |
8fb5debc MK |
6747 | _dst_pte = pte_mkyoung(_dst_pte); |
6748 | ||
d9712937 | 6749 | if (wp_enabled) |
6041c691 PX |
6750 | _dst_pte = huge_pte_mkuffd_wp(_dst_pte); |
6751 | ||
935d4f0c | 6752 | set_huge_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte, huge_page_size(h)); |
8fb5debc | 6753 | |
8fb5debc MK |
6754 | hugetlb_count_add(pages_per_huge_page(h), dst_mm); |
6755 | ||
6756 | /* No need to invalidate - it was non-present before */ | |
6757 | update_mmu_cache(dst_vma, dst_addr, dst_pte); | |
6758 | ||
6759 | spin_unlock(ptl); | |
f6191471 | 6760 | if (!is_continue) |
d0ce0e47 | 6761 | folio_set_hugetlb_migratable(folio); |
f6191471 | 6762 | if (vm_shared || is_continue) |
d0ce0e47 | 6763 | folio_unlock(folio); |
8fb5debc MK |
6764 | ret = 0; |
6765 | out: | |
6766 | return ret; | |
6767 | out_release_unlock: | |
6768 | spin_unlock(ptl); | |
f6191471 | 6769 | if (vm_shared || is_continue) |
d0ce0e47 | 6770 | folio_unlock(folio); |
5af10dfd | 6771 | out_release_nounlock: |
d0ce0e47 | 6772 | if (!folio_in_pagecache) |
d2d7bb44 | 6773 | restore_reserve_on_error(h, dst_vma, dst_addr, folio); |
d0ce0e47 | 6774 | folio_put(folio); |
8fb5debc MK |
6775 | goto out; |
6776 | } | |
714c1891 | 6777 | #endif /* CONFIG_USERFAULTFD */ |
8fb5debc | 6778 | |
57a196a5 | 6779 | struct page *hugetlb_follow_page_mask(struct vm_area_struct *vma, |
5502ea44 PX |
6780 | unsigned long address, unsigned int flags, |
6781 | unsigned int *page_mask) | |
57a196a5 MK |
6782 | { |
6783 | struct hstate *h = hstate_vma(vma); | |
6784 | struct mm_struct *mm = vma->vm_mm; | |
6785 | unsigned long haddr = address & huge_page_mask(h); | |
6786 | struct page *page = NULL; | |
6787 | spinlock_t *ptl; | |
6788 | pte_t *pte, entry; | |
458568c9 | 6789 | int ret; |
57a196a5 | 6790 | |
7d049f3a | 6791 | hugetlb_vma_lock_read(vma); |
9c67a207 | 6792 | pte = hugetlb_walk(vma, haddr, huge_page_size(h)); |
57a196a5 | 6793 | if (!pte) |
7d049f3a | 6794 | goto out_unlock; |
57a196a5 MK |
6795 | |
6796 | ptl = huge_pte_lock(h, mm, pte); | |
6797 | entry = huge_ptep_get(pte); | |
6798 | if (pte_present(entry)) { | |
458568c9 PX |
6799 | page = pte_page(entry); |
6800 | ||
6801 | if (!huge_pte_write(entry)) { | |
6802 | if (flags & FOLL_WRITE) { | |
6803 | page = NULL; | |
6804 | goto out; | |
6805 | } | |
6806 | ||
6807 | if (gup_must_unshare(vma, flags, page)) { | |
6808 | /* Tell the caller to do unsharing */ | |
6809 | page = ERR_PTR(-EMLINK); | |
6810 | goto out; | |
6811 | } | |
6812 | } | |
6813 | ||
426056ef | 6814 | page = nth_page(page, ((address & ~huge_page_mask(h)) >> PAGE_SHIFT)); |
458568c9 | 6815 | |
57a196a5 MK |
6816 | /* |
6817 | * Note that page may be a sub-page, and with vmemmap | |
6818 | * optimizations the page struct may be read only. | |
6819 | * try_grab_page() will increase the ref count on the | |
6820 | * head page, so this will be OK. | |
6821 | * | |
e2ca6ba6 LT |
6822 | * try_grab_page() should always be able to get the page here, |
6823 | * because we hold the ptl lock and have verified pte_present(). | |
57a196a5 | 6824 | */ |
458568c9 PX |
6825 | ret = try_grab_page(page, flags); |
6826 | ||
6827 | if (WARN_ON_ONCE(ret)) { | |
6828 | page = ERR_PTR(ret); | |
57a196a5 MK |
6829 | goto out; |
6830 | } | |
5502ea44 PX |
6831 | |
6832 | *page_mask = (1U << huge_page_order(h)) - 1; | |
57a196a5 MK |
6833 | } |
6834 | out: | |
6835 | spin_unlock(ptl); | |
7d049f3a PX |
6836 | out_unlock: |
6837 | hugetlb_vma_unlock_read(vma); | |
dd767aaa PX |
6838 | |
6839 | /* | |
6840 | * Fixup retval for dump requests: if pagecache doesn't exist, | |
6841 | * don't try to allocate a new page but just skip it. | |
6842 | */ | |
6843 | if (!page && (flags & FOLL_DUMP) && | |
6844 | !hugetlbfs_pagecache_present(h, vma, address)) | |
6845 | page = ERR_PTR(-EFAULT); | |
6846 | ||
57a196a5 MK |
6847 | return page; |
6848 | } | |
6849 | ||
a79390f5 | 6850 | long hugetlb_change_protection(struct vm_area_struct *vma, |
5a90d5a1 PX |
6851 | unsigned long address, unsigned long end, |
6852 | pgprot_t newprot, unsigned long cp_flags) | |
8f860591 ZY |
6853 | { |
6854 | struct mm_struct *mm = vma->vm_mm; | |
6855 | unsigned long start = address; | |
6856 | pte_t *ptep; | |
6857 | pte_t pte; | |
a5516438 | 6858 | struct hstate *h = hstate_vma(vma); |
a79390f5 | 6859 | long pages = 0, psize = huge_page_size(h); |
dff11abe | 6860 | bool shared_pmd = false; |
ac46d4f3 | 6861 | struct mmu_notifier_range range; |
e95a9851 | 6862 | unsigned long last_addr_mask; |
5a90d5a1 PX |
6863 | bool uffd_wp = cp_flags & MM_CP_UFFD_WP; |
6864 | bool uffd_wp_resolve = cp_flags & MM_CP_UFFD_WP_RESOLVE; | |
dff11abe MK |
6865 | |
6866 | /* | |
6867 | * In the case of shared PMDs, the area to flush could be beyond | |
ac46d4f3 | 6868 | * start/end. Set range.start/range.end to cover the maximum possible |
dff11abe MK |
6869 | * range if PMD sharing is possible. |
6870 | */ | |
7269f999 | 6871 | mmu_notifier_range_init(&range, MMU_NOTIFY_PROTECTION_VMA, |
7d4a8be0 | 6872 | 0, mm, start, end); |
ac46d4f3 | 6873 | adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end); |
8f860591 ZY |
6874 | |
6875 | BUG_ON(address >= end); | |
ac46d4f3 | 6876 | flush_cache_range(vma, range.start, range.end); |
8f860591 | 6877 | |
ac46d4f3 | 6878 | mmu_notifier_invalidate_range_start(&range); |
40549ba8 | 6879 | hugetlb_vma_lock_write(vma); |
83cde9e8 | 6880 | i_mmap_lock_write(vma->vm_file->f_mapping); |
40549ba8 | 6881 | last_addr_mask = hugetlb_mask_last_page(h); |
60dfaad6 | 6882 | for (; address < end; address += psize) { |
cb900f41 | 6883 | spinlock_t *ptl; |
9c67a207 | 6884 | ptep = hugetlb_walk(vma, address, psize); |
e95a9851 | 6885 | if (!ptep) { |
fed15f13 PX |
6886 | if (!uffd_wp) { |
6887 | address |= last_addr_mask; | |
6888 | continue; | |
6889 | } | |
6890 | /* | |
6891 | * Userfaultfd wr-protect requires pgtable | |
6892 | * pre-allocations to install pte markers. | |
6893 | */ | |
6894 | ptep = huge_pte_alloc(mm, vma, address, psize); | |
d1751118 PX |
6895 | if (!ptep) { |
6896 | pages = -ENOMEM; | |
fed15f13 | 6897 | break; |
d1751118 | 6898 | } |
e95a9851 | 6899 | } |
cb900f41 | 6900 | ptl = huge_pte_lock(h, mm, ptep); |
4ddb4d91 | 6901 | if (huge_pmd_unshare(mm, vma, address, ptep)) { |
60dfaad6 PX |
6902 | /* |
6903 | * When uffd-wp is enabled on the vma, unshare | |
6904 | * shouldn't happen at all. Warn about it if it | |
6905 | * happened due to some reason. | |
6906 | */ | |
6907 | WARN_ON_ONCE(uffd_wp || uffd_wp_resolve); | |
7da4d641 | 6908 | pages++; |
cb900f41 | 6909 | spin_unlock(ptl); |
dff11abe | 6910 | shared_pmd = true; |
4ddb4d91 | 6911 | address |= last_addr_mask; |
39dde65c | 6912 | continue; |
7da4d641 | 6913 | } |
a8bda28d NH |
6914 | pte = huge_ptep_get(ptep); |
6915 | if (unlikely(is_hugetlb_entry_hwpoisoned(pte))) { | |
0e678153 DH |
6916 | /* Nothing to do. */ |
6917 | } else if (unlikely(is_hugetlb_entry_migration(pte))) { | |
a8bda28d | 6918 | swp_entry_t entry = pte_to_swp_entry(pte); |
6c287605 | 6919 | struct page *page = pfn_swap_entry_to_page(entry); |
44f86392 | 6920 | pte_t newpte = pte; |
a8bda28d | 6921 | |
44f86392 | 6922 | if (is_writable_migration_entry(entry)) { |
6c287605 DH |
6923 | if (PageAnon(page)) |
6924 | entry = make_readable_exclusive_migration_entry( | |
6925 | swp_offset(entry)); | |
6926 | else | |
6927 | entry = make_readable_migration_entry( | |
6928 | swp_offset(entry)); | |
a8bda28d | 6929 | newpte = swp_entry_to_pte(entry); |
a8bda28d NH |
6930 | pages++; |
6931 | } | |
44f86392 DH |
6932 | |
6933 | if (uffd_wp) | |
6934 | newpte = pte_swp_mkuffd_wp(newpte); | |
6935 | else if (uffd_wp_resolve) | |
6936 | newpte = pte_swp_clear_uffd_wp(newpte); | |
6937 | if (!pte_same(pte, newpte)) | |
935d4f0c | 6938 | set_huge_pte_at(mm, address, ptep, newpte, psize); |
0e678153 DH |
6939 | } else if (unlikely(is_pte_marker(pte))) { |
6940 | /* No other markers apply for now. */ | |
6941 | WARN_ON_ONCE(!pte_marker_uffd_wp(pte)); | |
60dfaad6 | 6942 | if (uffd_wp_resolve) |
0e678153 | 6943 | /* Safe to modify directly (non-present->none). */ |
60dfaad6 | 6944 | huge_pte_clear(mm, address, ptep, psize); |
0e678153 | 6945 | } else if (!huge_pte_none(pte)) { |
023bdd00 | 6946 | pte_t old_pte; |
79c1c594 | 6947 | unsigned int shift = huge_page_shift(hstate_vma(vma)); |
023bdd00 AK |
6948 | |
6949 | old_pte = huge_ptep_modify_prot_start(vma, address, ptep); | |
16785bd7 | 6950 | pte = huge_pte_modify(old_pte, newprot); |
79c1c594 | 6951 | pte = arch_make_huge_pte(pte, shift, vma->vm_flags); |
5a90d5a1 | 6952 | if (uffd_wp) |
f1eb1bac | 6953 | pte = huge_pte_mkuffd_wp(pte); |
5a90d5a1 PX |
6954 | else if (uffd_wp_resolve) |
6955 | pte = huge_pte_clear_uffd_wp(pte); | |
023bdd00 | 6956 | huge_ptep_modify_prot_commit(vma, address, ptep, old_pte, pte); |
7da4d641 | 6957 | pages++; |
60dfaad6 PX |
6958 | } else { |
6959 | /* None pte */ | |
6960 | if (unlikely(uffd_wp)) | |
6961 | /* Safe to modify directly (none->non-present). */ | |
6962 | set_huge_pte_at(mm, address, ptep, | |
935d4f0c RR |
6963 | make_pte_marker(PTE_MARKER_UFFD_WP), |
6964 | psize); | |
8f860591 | 6965 | } |
cb900f41 | 6966 | spin_unlock(ptl); |
8f860591 | 6967 | } |
d833352a | 6968 | /* |
c8c06efa | 6969 | * Must flush TLB before releasing i_mmap_rwsem: x86's huge_pmd_unshare |
d833352a | 6970 | * may have cleared our pud entry and done put_page on the page table: |
c8c06efa | 6971 | * once we release i_mmap_rwsem, another task can do the final put_page |
dff11abe MK |
6972 | * and that page table be reused and filled with junk. If we actually |
6973 | * did unshare a page of pmds, flush the range corresponding to the pud. | |
d833352a | 6974 | */ |
dff11abe | 6975 | if (shared_pmd) |
ac46d4f3 | 6976 | flush_hugetlb_tlb_range(vma, range.start, range.end); |
dff11abe MK |
6977 | else |
6978 | flush_hugetlb_tlb_range(vma, start, end); | |
0f10851e | 6979 | /* |
1af5a810 AP |
6980 | * No need to call mmu_notifier_arch_invalidate_secondary_tlbs() we are |
6981 | * downgrading page table protection not changing it to point to a new | |
6982 | * page. | |
0f10851e | 6983 | * |
ee65728e | 6984 | * See Documentation/mm/mmu_notifier.rst |
0f10851e | 6985 | */ |
83cde9e8 | 6986 | i_mmap_unlock_write(vma->vm_file->f_mapping); |
40549ba8 | 6987 | hugetlb_vma_unlock_write(vma); |
ac46d4f3 | 6988 | mmu_notifier_invalidate_range_end(&range); |
7da4d641 | 6989 | |
d1751118 | 6990 | return pages > 0 ? (pages << h->order) : pages; |
8f860591 ZY |
6991 | } |
6992 | ||
33b8f84a MK |
6993 | /* Return true if reservation was successful, false otherwise. */ |
6994 | bool hugetlb_reserve_pages(struct inode *inode, | |
a1e78772 | 6995 | long from, long to, |
5a6fe125 | 6996 | struct vm_area_struct *vma, |
ca16d140 | 6997 | vm_flags_t vm_flags) |
e4e574b7 | 6998 | { |
c5094ec7 | 6999 | long chg = -1, add = -1; |
a5516438 | 7000 | struct hstate *h = hstate_inode(inode); |
90481622 | 7001 | struct hugepage_subpool *spool = subpool_inode(inode); |
9119a41e | 7002 | struct resv_map *resv_map; |
075a61d0 | 7003 | struct hugetlb_cgroup *h_cg = NULL; |
0db9d74e | 7004 | long gbl_reserve, regions_needed = 0; |
e4e574b7 | 7005 | |
63489f8e MK |
7006 | /* This should never happen */ |
7007 | if (from > to) { | |
7008 | VM_WARN(1, "%s called with a negative range\n", __func__); | |
33b8f84a | 7009 | return false; |
63489f8e MK |
7010 | } |
7011 | ||
8d9bfb26 | 7012 | /* |
e700898f MK |
7013 | * vma specific semaphore used for pmd sharing and fault/truncation |
7014 | * synchronization | |
8d9bfb26 MK |
7015 | */ |
7016 | hugetlb_vma_lock_alloc(vma); | |
7017 | ||
17c9d12e MG |
7018 | /* |
7019 | * Only apply hugepage reservation if asked. At fault time, an | |
7020 | * attempt will be made for VM_NORESERVE to allocate a page | |
90481622 | 7021 | * without using reserves |
17c9d12e | 7022 | */ |
ca16d140 | 7023 | if (vm_flags & VM_NORESERVE) |
33b8f84a | 7024 | return true; |
17c9d12e | 7025 | |
a1e78772 MG |
7026 | /* |
7027 | * Shared mappings base their reservation on the number of pages that | |
7028 | * are already allocated on behalf of the file. Private mappings need | |
7029 | * to reserve the full area even if read-only as mprotect() may be | |
7030 | * called to make the mapping read-write. Assume !vma is a shm mapping | |
7031 | */ | |
9119a41e | 7032 | if (!vma || vma->vm_flags & VM_MAYSHARE) { |
f27a5136 MK |
7033 | /* |
7034 | * resv_map can not be NULL as hugetlb_reserve_pages is only | |
7035 | * called for inodes for which resv_maps were created (see | |
7036 | * hugetlbfs_get_inode). | |
7037 | */ | |
4e35f483 | 7038 | resv_map = inode_resv_map(inode); |
9119a41e | 7039 | |
0db9d74e | 7040 | chg = region_chg(resv_map, from, to, ®ions_needed); |
9119a41e | 7041 | } else { |
e9fe92ae | 7042 | /* Private mapping. */ |
9119a41e | 7043 | resv_map = resv_map_alloc(); |
17c9d12e | 7044 | if (!resv_map) |
8d9bfb26 | 7045 | goto out_err; |
17c9d12e | 7046 | |
a1e78772 | 7047 | chg = to - from; |
84afd99b | 7048 | |
17c9d12e MG |
7049 | set_vma_resv_map(vma, resv_map); |
7050 | set_vma_resv_flags(vma, HPAGE_RESV_OWNER); | |
7051 | } | |
7052 | ||
33b8f84a | 7053 | if (chg < 0) |
c50ac050 | 7054 | goto out_err; |
8a630112 | 7055 | |
33b8f84a MK |
7056 | if (hugetlb_cgroup_charge_cgroup_rsvd(hstate_index(h), |
7057 | chg * pages_per_huge_page(h), &h_cg) < 0) | |
075a61d0 | 7058 | goto out_err; |
075a61d0 MA |
7059 | |
7060 | if (vma && !(vma->vm_flags & VM_MAYSHARE) && h_cg) { | |
7061 | /* For private mappings, the hugetlb_cgroup uncharge info hangs | |
7062 | * of the resv_map. | |
7063 | */ | |
7064 | resv_map_set_hugetlb_cgroup_uncharge_info(resv_map, h_cg, h); | |
7065 | } | |
7066 | ||
1c5ecae3 MK |
7067 | /* |
7068 | * There must be enough pages in the subpool for the mapping. If | |
7069 | * the subpool has a minimum size, there may be some global | |
7070 | * reservations already in place (gbl_reserve). | |
7071 | */ | |
7072 | gbl_reserve = hugepage_subpool_get_pages(spool, chg); | |
33b8f84a | 7073 | if (gbl_reserve < 0) |
075a61d0 | 7074 | goto out_uncharge_cgroup; |
5a6fe125 MG |
7075 | |
7076 | /* | |
17c9d12e | 7077 | * Check enough hugepages are available for the reservation. |
90481622 | 7078 | * Hand the pages back to the subpool if there are not |
5a6fe125 | 7079 | */ |
33b8f84a | 7080 | if (hugetlb_acct_memory(h, gbl_reserve) < 0) |
075a61d0 | 7081 | goto out_put_pages; |
17c9d12e MG |
7082 | |
7083 | /* | |
7084 | * Account for the reservations made. Shared mappings record regions | |
7085 | * that have reservations as they are shared by multiple VMAs. | |
7086 | * When the last VMA disappears, the region map says how much | |
7087 | * the reservation was and the page cache tells how much of | |
7088 | * the reservation was consumed. Private mappings are per-VMA and | |
7089 | * only the consumed reservations are tracked. When the VMA | |
7090 | * disappears, the original reservation is the VMA size and the | |
7091 | * consumed reservations are stored in the map. Hence, nothing | |
7092 | * else has to be done for private mappings here | |
7093 | */ | |
33039678 | 7094 | if (!vma || vma->vm_flags & VM_MAYSHARE) { |
075a61d0 | 7095 | add = region_add(resv_map, from, to, regions_needed, h, h_cg); |
0db9d74e MA |
7096 | |
7097 | if (unlikely(add < 0)) { | |
7098 | hugetlb_acct_memory(h, -gbl_reserve); | |
075a61d0 | 7099 | goto out_put_pages; |
0db9d74e | 7100 | } else if (unlikely(chg > add)) { |
33039678 MK |
7101 | /* |
7102 | * pages in this range were added to the reserve | |
7103 | * map between region_chg and region_add. This | |
d0ce0e47 | 7104 | * indicates a race with alloc_hugetlb_folio. Adjust |
33039678 MK |
7105 | * the subpool and reserve counts modified above |
7106 | * based on the difference. | |
7107 | */ | |
7108 | long rsv_adjust; | |
7109 | ||
d85aecf2 ML |
7110 | /* |
7111 | * hugetlb_cgroup_uncharge_cgroup_rsvd() will put the | |
7112 | * reference to h_cg->css. See comment below for detail. | |
7113 | */ | |
075a61d0 MA |
7114 | hugetlb_cgroup_uncharge_cgroup_rsvd( |
7115 | hstate_index(h), | |
7116 | (chg - add) * pages_per_huge_page(h), h_cg); | |
7117 | ||
33039678 MK |
7118 | rsv_adjust = hugepage_subpool_put_pages(spool, |
7119 | chg - add); | |
7120 | hugetlb_acct_memory(h, -rsv_adjust); | |
d85aecf2 ML |
7121 | } else if (h_cg) { |
7122 | /* | |
7123 | * The file_regions will hold their own reference to | |
7124 | * h_cg->css. So we should release the reference held | |
7125 | * via hugetlb_cgroup_charge_cgroup_rsvd() when we are | |
7126 | * done. | |
7127 | */ | |
7128 | hugetlb_cgroup_put_rsvd_cgroup(h_cg); | |
33039678 MK |
7129 | } |
7130 | } | |
33b8f84a MK |
7131 | return true; |
7132 | ||
075a61d0 MA |
7133 | out_put_pages: |
7134 | /* put back original number of pages, chg */ | |
7135 | (void)hugepage_subpool_put_pages(spool, chg); | |
7136 | out_uncharge_cgroup: | |
7137 | hugetlb_cgroup_uncharge_cgroup_rsvd(hstate_index(h), | |
7138 | chg * pages_per_huge_page(h), h_cg); | |
c50ac050 | 7139 | out_err: |
8d9bfb26 | 7140 | hugetlb_vma_lock_free(vma); |
5e911373 | 7141 | if (!vma || vma->vm_flags & VM_MAYSHARE) |
0db9d74e MA |
7142 | /* Only call region_abort if the region_chg succeeded but the |
7143 | * region_add failed or didn't run. | |
7144 | */ | |
7145 | if (chg >= 0 && add < 0) | |
7146 | region_abort(resv_map, from, to, regions_needed); | |
92fe9dcb | 7147 | if (vma && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { |
f031dd27 | 7148 | kref_put(&resv_map->refs, resv_map_release); |
92fe9dcb RR |
7149 | set_vma_resv_map(vma, NULL); |
7150 | } | |
33b8f84a | 7151 | return false; |
a43a8c39 CK |
7152 | } |
7153 | ||
b5cec28d MK |
7154 | long hugetlb_unreserve_pages(struct inode *inode, long start, long end, |
7155 | long freed) | |
a43a8c39 | 7156 | { |
a5516438 | 7157 | struct hstate *h = hstate_inode(inode); |
4e35f483 | 7158 | struct resv_map *resv_map = inode_resv_map(inode); |
9119a41e | 7159 | long chg = 0; |
90481622 | 7160 | struct hugepage_subpool *spool = subpool_inode(inode); |
1c5ecae3 | 7161 | long gbl_reserve; |
45c682a6 | 7162 | |
f27a5136 MK |
7163 | /* |
7164 | * Since this routine can be called in the evict inode path for all | |
7165 | * hugetlbfs inodes, resv_map could be NULL. | |
7166 | */ | |
b5cec28d MK |
7167 | if (resv_map) { |
7168 | chg = region_del(resv_map, start, end); | |
7169 | /* | |
7170 | * region_del() can fail in the rare case where a region | |
7171 | * must be split and another region descriptor can not be | |
7172 | * allocated. If end == LONG_MAX, it will not fail. | |
7173 | */ | |
7174 | if (chg < 0) | |
7175 | return chg; | |
7176 | } | |
7177 | ||
45c682a6 | 7178 | spin_lock(&inode->i_lock); |
e4c6f8be | 7179 | inode->i_blocks -= (blocks_per_huge_page(h) * freed); |
45c682a6 KC |
7180 | spin_unlock(&inode->i_lock); |
7181 | ||
1c5ecae3 MK |
7182 | /* |
7183 | * If the subpool has a minimum size, the number of global | |
7184 | * reservations to be released may be adjusted. | |
dddf31a4 ML |
7185 | * |
7186 | * Note that !resv_map implies freed == 0. So (chg - freed) | |
7187 | * won't go negative. | |
1c5ecae3 MK |
7188 | */ |
7189 | gbl_reserve = hugepage_subpool_put_pages(spool, (chg - freed)); | |
7190 | hugetlb_acct_memory(h, -gbl_reserve); | |
b5cec28d MK |
7191 | |
7192 | return 0; | |
a43a8c39 | 7193 | } |
93f70f90 | 7194 | |
3212b535 SC |
7195 | #ifdef CONFIG_ARCH_WANT_HUGE_PMD_SHARE |
7196 | static unsigned long page_table_shareable(struct vm_area_struct *svma, | |
7197 | struct vm_area_struct *vma, | |
7198 | unsigned long addr, pgoff_t idx) | |
7199 | { | |
7200 | unsigned long saddr = ((idx - svma->vm_pgoff) << PAGE_SHIFT) + | |
7201 | svma->vm_start; | |
7202 | unsigned long sbase = saddr & PUD_MASK; | |
7203 | unsigned long s_end = sbase + PUD_SIZE; | |
7204 | ||
7205 | /* Allow segments to share if only one is marked locked */ | |
e430a95a SB |
7206 | unsigned long vm_flags = vma->vm_flags & ~VM_LOCKED_MASK; |
7207 | unsigned long svm_flags = svma->vm_flags & ~VM_LOCKED_MASK; | |
3212b535 SC |
7208 | |
7209 | /* | |
7210 | * match the virtual addresses, permission and the alignment of the | |
7211 | * page table page. | |
131a79b4 MK |
7212 | * |
7213 | * Also, vma_lock (vm_private_data) is required for sharing. | |
3212b535 SC |
7214 | */ |
7215 | if (pmd_index(addr) != pmd_index(saddr) || | |
7216 | vm_flags != svm_flags || | |
131a79b4 MK |
7217 | !range_in_vma(svma, sbase, s_end) || |
7218 | !svma->vm_private_data) | |
3212b535 SC |
7219 | return 0; |
7220 | ||
7221 | return saddr; | |
7222 | } | |
7223 | ||
bbff39cc | 7224 | bool want_pmd_share(struct vm_area_struct *vma, unsigned long addr) |
3212b535 | 7225 | { |
bbff39cc MK |
7226 | unsigned long start = addr & PUD_MASK; |
7227 | unsigned long end = start + PUD_SIZE; | |
7228 | ||
8d9bfb26 MK |
7229 | #ifdef CONFIG_USERFAULTFD |
7230 | if (uffd_disable_huge_pmd_share(vma)) | |
7231 | return false; | |
7232 | #endif | |
3212b535 SC |
7233 | /* |
7234 | * check on proper vm_flags and page table alignment | |
7235 | */ | |
8d9bfb26 MK |
7236 | if (!(vma->vm_flags & VM_MAYSHARE)) |
7237 | return false; | |
bbff39cc | 7238 | if (!vma->vm_private_data) /* vma lock required for sharing */ |
8d9bfb26 MK |
7239 | return false; |
7240 | if (!range_in_vma(vma, start, end)) | |
7241 | return false; | |
7242 | return true; | |
7243 | } | |
7244 | ||
017b1660 MK |
7245 | /* |
7246 | * Determine if start,end range within vma could be mapped by shared pmd. | |
7247 | * If yes, adjust start and end to cover range associated with possible | |
7248 | * shared pmd mappings. | |
7249 | */ | |
7250 | void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma, | |
7251 | unsigned long *start, unsigned long *end) | |
7252 | { | |
a1ba9da8 LX |
7253 | unsigned long v_start = ALIGN(vma->vm_start, PUD_SIZE), |
7254 | v_end = ALIGN_DOWN(vma->vm_end, PUD_SIZE); | |
017b1660 | 7255 | |
a1ba9da8 | 7256 | /* |
f0953a1b IM |
7257 | * vma needs to span at least one aligned PUD size, and the range |
7258 | * must be at least partially within in. | |
a1ba9da8 LX |
7259 | */ |
7260 | if (!(vma->vm_flags & VM_MAYSHARE) || !(v_end > v_start) || | |
7261 | (*end <= v_start) || (*start >= v_end)) | |
017b1660 MK |
7262 | return; |
7263 | ||
75802ca6 | 7264 | /* Extend the range to be PUD aligned for a worst case scenario */ |
a1ba9da8 LX |
7265 | if (*start > v_start) |
7266 | *start = ALIGN_DOWN(*start, PUD_SIZE); | |
017b1660 | 7267 | |
a1ba9da8 LX |
7268 | if (*end < v_end) |
7269 | *end = ALIGN(*end, PUD_SIZE); | |
017b1660 MK |
7270 | } |
7271 | ||
3212b535 SC |
7272 | /* |
7273 | * Search for a shareable pmd page for hugetlb. In any case calls pmd_alloc() | |
7274 | * and returns the corresponding pte. While this is not necessary for the | |
7275 | * !shared pmd case because we can allocate the pmd later as well, it makes the | |
3a47c54f MK |
7276 | * code much cleaner. pmd allocation is essential for the shared case because |
7277 | * pud has to be populated inside the same i_mmap_rwsem section - otherwise | |
7278 | * racing tasks could either miss the sharing (see huge_pte_offset) or select a | |
7279 | * bad pmd for sharing. | |
3212b535 | 7280 | */ |
aec44e0f PX |
7281 | pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma, |
7282 | unsigned long addr, pud_t *pud) | |
3212b535 | 7283 | { |
3212b535 SC |
7284 | struct address_space *mapping = vma->vm_file->f_mapping; |
7285 | pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) + | |
7286 | vma->vm_pgoff; | |
7287 | struct vm_area_struct *svma; | |
7288 | unsigned long saddr; | |
7289 | pte_t *spte = NULL; | |
7290 | pte_t *pte; | |
7291 | ||
3a47c54f | 7292 | i_mmap_lock_read(mapping); |
3212b535 SC |
7293 | vma_interval_tree_foreach(svma, &mapping->i_mmap, idx, idx) { |
7294 | if (svma == vma) | |
7295 | continue; | |
7296 | ||
7297 | saddr = page_table_shareable(svma, vma, addr, idx); | |
7298 | if (saddr) { | |
9c67a207 PX |
7299 | spte = hugetlb_walk(svma, saddr, |
7300 | vma_mmu_pagesize(svma)); | |
3212b535 SC |
7301 | if (spte) { |
7302 | get_page(virt_to_page(spte)); | |
7303 | break; | |
7304 | } | |
7305 | } | |
7306 | } | |
7307 | ||
7308 | if (!spte) | |
7309 | goto out; | |
7310 | ||
349d1670 | 7311 | spin_lock(&mm->page_table_lock); |
dc6c9a35 | 7312 | if (pud_none(*pud)) { |
3212b535 SC |
7313 | pud_populate(mm, pud, |
7314 | (pmd_t *)((unsigned long)spte & PAGE_MASK)); | |
c17b1f42 | 7315 | mm_inc_nr_pmds(mm); |
dc6c9a35 | 7316 | } else { |
3212b535 | 7317 | put_page(virt_to_page(spte)); |
dc6c9a35 | 7318 | } |
349d1670 | 7319 | spin_unlock(&mm->page_table_lock); |
3212b535 SC |
7320 | out: |
7321 | pte = (pte_t *)pmd_alloc(mm, pud, addr); | |
3a47c54f | 7322 | i_mmap_unlock_read(mapping); |
3212b535 SC |
7323 | return pte; |
7324 | } | |
7325 | ||
7326 | /* | |
7327 | * unmap huge page backed by shared pte. | |
7328 | * | |
7329 | * Hugetlb pte page is ref counted at the time of mapping. If pte is shared | |
7330 | * indicated by page_count > 1, unmap is achieved by clearing pud and | |
7331 | * decrementing the ref count. If count == 1, the pte page is not shared. | |
7332 | * | |
3a47c54f | 7333 | * Called with page table lock held. |
3212b535 SC |
7334 | * |
7335 | * returns: 1 successfully unmapped a shared pte page | |
7336 | * 0 the underlying pte page is not shared, or it is the last user | |
7337 | */ | |
34ae204f | 7338 | int huge_pmd_unshare(struct mm_struct *mm, struct vm_area_struct *vma, |
4ddb4d91 | 7339 | unsigned long addr, pte_t *ptep) |
3212b535 | 7340 | { |
4ddb4d91 MK |
7341 | pgd_t *pgd = pgd_offset(mm, addr); |
7342 | p4d_t *p4d = p4d_offset(pgd, addr); | |
7343 | pud_t *pud = pud_offset(p4d, addr); | |
3212b535 | 7344 | |
34ae204f | 7345 | i_mmap_assert_write_locked(vma->vm_file->f_mapping); |
40549ba8 | 7346 | hugetlb_vma_assert_locked(vma); |
3212b535 SC |
7347 | BUG_ON(page_count(virt_to_page(ptep)) == 0); |
7348 | if (page_count(virt_to_page(ptep)) == 1) | |
7349 | return 0; | |
7350 | ||
7351 | pud_clear(pud); | |
7352 | put_page(virt_to_page(ptep)); | |
dc6c9a35 | 7353 | mm_dec_nr_pmds(mm); |
3212b535 SC |
7354 | return 1; |
7355 | } | |
c1991e07 | 7356 | |
9e5fc74c | 7357 | #else /* !CONFIG_ARCH_WANT_HUGE_PMD_SHARE */ |
8d9bfb26 | 7358 | |
aec44e0f PX |
7359 | pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma, |
7360 | unsigned long addr, pud_t *pud) | |
9e5fc74c SC |
7361 | { |
7362 | return NULL; | |
7363 | } | |
e81f2d22 | 7364 | |
34ae204f | 7365 | int huge_pmd_unshare(struct mm_struct *mm, struct vm_area_struct *vma, |
4ddb4d91 | 7366 | unsigned long addr, pte_t *ptep) |
e81f2d22 ZZ |
7367 | { |
7368 | return 0; | |
7369 | } | |
017b1660 MK |
7370 | |
7371 | void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma, | |
7372 | unsigned long *start, unsigned long *end) | |
7373 | { | |
7374 | } | |
c1991e07 PX |
7375 | |
7376 | bool want_pmd_share(struct vm_area_struct *vma, unsigned long addr) | |
7377 | { | |
7378 | return false; | |
7379 | } | |
3212b535 SC |
7380 | #endif /* CONFIG_ARCH_WANT_HUGE_PMD_SHARE */ |
7381 | ||
9e5fc74c | 7382 | #ifdef CONFIG_ARCH_WANT_GENERAL_HUGETLB |
aec44e0f | 7383 | pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, |
9e5fc74c SC |
7384 | unsigned long addr, unsigned long sz) |
7385 | { | |
7386 | pgd_t *pgd; | |
c2febafc | 7387 | p4d_t *p4d; |
9e5fc74c SC |
7388 | pud_t *pud; |
7389 | pte_t *pte = NULL; | |
7390 | ||
7391 | pgd = pgd_offset(mm, addr); | |
f4f0a3d8 KS |
7392 | p4d = p4d_alloc(mm, pgd, addr); |
7393 | if (!p4d) | |
7394 | return NULL; | |
c2febafc | 7395 | pud = pud_alloc(mm, p4d, addr); |
9e5fc74c SC |
7396 | if (pud) { |
7397 | if (sz == PUD_SIZE) { | |
7398 | pte = (pte_t *)pud; | |
7399 | } else { | |
7400 | BUG_ON(sz != PMD_SIZE); | |
c1991e07 | 7401 | if (want_pmd_share(vma, addr) && pud_none(*pud)) |
aec44e0f | 7402 | pte = huge_pmd_share(mm, vma, addr, pud); |
9e5fc74c SC |
7403 | else |
7404 | pte = (pte_t *)pmd_alloc(mm, pud, addr); | |
7405 | } | |
7406 | } | |
191fcdb6 JH |
7407 | |
7408 | if (pte) { | |
7409 | pte_t pteval = ptep_get_lockless(pte); | |
7410 | ||
7411 | BUG_ON(pte_present(pteval) && !pte_huge(pteval)); | |
7412 | } | |
9e5fc74c SC |
7413 | |
7414 | return pte; | |
7415 | } | |
7416 | ||
9b19df29 PA |
7417 | /* |
7418 | * huge_pte_offset() - Walk the page table to resolve the hugepage | |
7419 | * entry at address @addr | |
7420 | * | |
8ac0b81a LX |
7421 | * Return: Pointer to page table entry (PUD or PMD) for |
7422 | * address @addr, or NULL if a !p*d_present() entry is encountered and the | |
9b19df29 PA |
7423 | * size @sz doesn't match the hugepage size at this level of the page |
7424 | * table. | |
7425 | */ | |
7868a208 PA |
7426 | pte_t *huge_pte_offset(struct mm_struct *mm, |
7427 | unsigned long addr, unsigned long sz) | |
9e5fc74c SC |
7428 | { |
7429 | pgd_t *pgd; | |
c2febafc | 7430 | p4d_t *p4d; |
8ac0b81a LX |
7431 | pud_t *pud; |
7432 | pmd_t *pmd; | |
9e5fc74c SC |
7433 | |
7434 | pgd = pgd_offset(mm, addr); | |
c2febafc KS |
7435 | if (!pgd_present(*pgd)) |
7436 | return NULL; | |
7437 | p4d = p4d_offset(pgd, addr); | |
7438 | if (!p4d_present(*p4d)) | |
7439 | return NULL; | |
9b19df29 | 7440 | |
c2febafc | 7441 | pud = pud_offset(p4d, addr); |
8ac0b81a LX |
7442 | if (sz == PUD_SIZE) |
7443 | /* must be pud huge, non-present or none */ | |
c2febafc | 7444 | return (pte_t *)pud; |
8ac0b81a | 7445 | if (!pud_present(*pud)) |
9b19df29 | 7446 | return NULL; |
8ac0b81a | 7447 | /* must have a valid entry and size to go further */ |
9b19df29 | 7448 | |
8ac0b81a LX |
7449 | pmd = pmd_offset(pud, addr); |
7450 | /* must be pmd huge, non-present or none */ | |
7451 | return (pte_t *)pmd; | |
9e5fc74c SC |
7452 | } |
7453 | ||
e95a9851 MK |
7454 | /* |
7455 | * Return a mask that can be used to update an address to the last huge | |
7456 | * page in a page table page mapping size. Used to skip non-present | |
7457 | * page table entries when linearly scanning address ranges. Architectures | |
7458 | * with unique huge page to page table relationships can define their own | |
7459 | * version of this routine. | |
7460 | */ | |
7461 | unsigned long hugetlb_mask_last_page(struct hstate *h) | |
7462 | { | |
7463 | unsigned long hp_size = huge_page_size(h); | |
7464 | ||
7465 | if (hp_size == PUD_SIZE) | |
7466 | return P4D_SIZE - PUD_SIZE; | |
7467 | else if (hp_size == PMD_SIZE) | |
7468 | return PUD_SIZE - PMD_SIZE; | |
7469 | else | |
7470 | return 0UL; | |
7471 | } | |
7472 | ||
7473 | #else | |
7474 | ||
7475 | /* See description above. Architectures can provide their own version. */ | |
7476 | __weak unsigned long hugetlb_mask_last_page(struct hstate *h) | |
7477 | { | |
4ddb4d91 MK |
7478 | #ifdef CONFIG_ARCH_WANT_HUGE_PMD_SHARE |
7479 | if (huge_page_size(h) == PMD_SIZE) | |
7480 | return PUD_SIZE - PMD_SIZE; | |
7481 | #endif | |
e95a9851 MK |
7482 | return 0UL; |
7483 | } | |
7484 | ||
61f77eda NH |
7485 | #endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */ |
7486 | ||
7487 | /* | |
7488 | * These functions are overwritable if your architecture needs its own | |
7489 | * behavior. | |
7490 | */ | |
9747b9e9 | 7491 | bool isolate_hugetlb(struct folio *folio, struct list_head *list) |
31caf665 | 7492 | { |
9747b9e9 | 7493 | bool ret = true; |
bcc54222 | 7494 | |
db71ef79 | 7495 | spin_lock_irq(&hugetlb_lock); |
6aa3a920 SK |
7496 | if (!folio_test_hugetlb(folio) || |
7497 | !folio_test_hugetlb_migratable(folio) || | |
7498 | !folio_try_get(folio)) { | |
9747b9e9 | 7499 | ret = false; |
bcc54222 NH |
7500 | goto unlock; |
7501 | } | |
6aa3a920 SK |
7502 | folio_clear_hugetlb_migratable(folio); |
7503 | list_move_tail(&folio->lru, list); | |
bcc54222 | 7504 | unlock: |
db71ef79 | 7505 | spin_unlock_irq(&hugetlb_lock); |
bcc54222 | 7506 | return ret; |
31caf665 NH |
7507 | } |
7508 | ||
04bac040 | 7509 | int get_hwpoison_hugetlb_folio(struct folio *folio, bool *hugetlb, bool unpoison) |
25182f05 NH |
7510 | { |
7511 | int ret = 0; | |
7512 | ||
7513 | *hugetlb = false; | |
7514 | spin_lock_irq(&hugetlb_lock); | |
04bac040 | 7515 | if (folio_test_hugetlb(folio)) { |
25182f05 | 7516 | *hugetlb = true; |
04bac040 | 7517 | if (folio_test_hugetlb_freed(folio)) |
b283d983 | 7518 | ret = 0; |
04bac040 SK |
7519 | else if (folio_test_hugetlb_migratable(folio) || unpoison) |
7520 | ret = folio_try_get(folio); | |
0ed950d1 NH |
7521 | else |
7522 | ret = -EBUSY; | |
25182f05 NH |
7523 | } |
7524 | spin_unlock_irq(&hugetlb_lock); | |
7525 | return ret; | |
7526 | } | |
7527 | ||
e591ef7d NH |
7528 | int get_huge_page_for_hwpoison(unsigned long pfn, int flags, |
7529 | bool *migratable_cleared) | |
405ce051 NH |
7530 | { |
7531 | int ret; | |
7532 | ||
7533 | spin_lock_irq(&hugetlb_lock); | |
e591ef7d | 7534 | ret = __get_huge_page_for_hwpoison(pfn, flags, migratable_cleared); |
405ce051 NH |
7535 | spin_unlock_irq(&hugetlb_lock); |
7536 | return ret; | |
7537 | } | |
7538 | ||
ea8e72f4 | 7539 | void folio_putback_active_hugetlb(struct folio *folio) |
31caf665 | 7540 | { |
db71ef79 | 7541 | spin_lock_irq(&hugetlb_lock); |
ea8e72f4 SK |
7542 | folio_set_hugetlb_migratable(folio); |
7543 | list_move_tail(&folio->lru, &(folio_hstate(folio))->hugepage_activelist); | |
db71ef79 | 7544 | spin_unlock_irq(&hugetlb_lock); |
ea8e72f4 | 7545 | folio_put(folio); |
31caf665 | 7546 | } |
ab5ac90a | 7547 | |
345c62d1 | 7548 | void move_hugetlb_state(struct folio *old_folio, struct folio *new_folio, int reason) |
ab5ac90a | 7549 | { |
345c62d1 | 7550 | struct hstate *h = folio_hstate(old_folio); |
ab5ac90a | 7551 | |
345c62d1 SK |
7552 | hugetlb_cgroup_migrate(old_folio, new_folio); |
7553 | set_page_owner_migrate_reason(&new_folio->page, reason); | |
ab5ac90a MH |
7554 | |
7555 | /* | |
345c62d1 | 7556 | * transfer temporary state of the new hugetlb folio. This is |
ab5ac90a MH |
7557 | * reverse to other transitions because the newpage is going to |
7558 | * be final while the old one will be freed so it takes over | |
7559 | * the temporary status. | |
7560 | * | |
7561 | * Also note that we have to transfer the per-node surplus state | |
7562 | * here as well otherwise the global surplus count will not match | |
7563 | * the per-node's. | |
7564 | */ | |
345c62d1 SK |
7565 | if (folio_test_hugetlb_temporary(new_folio)) { |
7566 | int old_nid = folio_nid(old_folio); | |
7567 | int new_nid = folio_nid(new_folio); | |
7568 | ||
345c62d1 SK |
7569 | folio_set_hugetlb_temporary(old_folio); |
7570 | folio_clear_hugetlb_temporary(new_folio); | |
ab5ac90a | 7571 | |
ab5ac90a | 7572 | |
5af1ab1d ML |
7573 | /* |
7574 | * There is no need to transfer the per-node surplus state | |
7575 | * when we do not cross the node. | |
7576 | */ | |
7577 | if (new_nid == old_nid) | |
7578 | return; | |
db71ef79 | 7579 | spin_lock_irq(&hugetlb_lock); |
ab5ac90a MH |
7580 | if (h->surplus_huge_pages_node[old_nid]) { |
7581 | h->surplus_huge_pages_node[old_nid]--; | |
7582 | h->surplus_huge_pages_node[new_nid]++; | |
7583 | } | |
db71ef79 | 7584 | spin_unlock_irq(&hugetlb_lock); |
ab5ac90a MH |
7585 | } |
7586 | } | |
cf11e85f | 7587 | |
b30c14cd JH |
7588 | static void hugetlb_unshare_pmds(struct vm_area_struct *vma, |
7589 | unsigned long start, | |
7590 | unsigned long end) | |
6dfeaff9 PX |
7591 | { |
7592 | struct hstate *h = hstate_vma(vma); | |
7593 | unsigned long sz = huge_page_size(h); | |
7594 | struct mm_struct *mm = vma->vm_mm; | |
7595 | struct mmu_notifier_range range; | |
b30c14cd | 7596 | unsigned long address; |
6dfeaff9 PX |
7597 | spinlock_t *ptl; |
7598 | pte_t *ptep; | |
7599 | ||
7600 | if (!(vma->vm_flags & VM_MAYSHARE)) | |
7601 | return; | |
7602 | ||
6dfeaff9 PX |
7603 | if (start >= end) |
7604 | return; | |
7605 | ||
9c8bbfac | 7606 | flush_cache_range(vma, start, end); |
6dfeaff9 PX |
7607 | /* |
7608 | * No need to call adjust_range_if_pmd_sharing_possible(), because | |
7609 | * we have already done the PUD_SIZE alignment. | |
7610 | */ | |
7d4a8be0 | 7611 | mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm, |
6dfeaff9 PX |
7612 | start, end); |
7613 | mmu_notifier_invalidate_range_start(&range); | |
40549ba8 | 7614 | hugetlb_vma_lock_write(vma); |
6dfeaff9 PX |
7615 | i_mmap_lock_write(vma->vm_file->f_mapping); |
7616 | for (address = start; address < end; address += PUD_SIZE) { | |
9c67a207 | 7617 | ptep = hugetlb_walk(vma, address, sz); |
6dfeaff9 PX |
7618 | if (!ptep) |
7619 | continue; | |
7620 | ptl = huge_pte_lock(h, mm, ptep); | |
4ddb4d91 | 7621 | huge_pmd_unshare(mm, vma, address, ptep); |
6dfeaff9 PX |
7622 | spin_unlock(ptl); |
7623 | } | |
7624 | flush_hugetlb_tlb_range(vma, start, end); | |
7625 | i_mmap_unlock_write(vma->vm_file->f_mapping); | |
40549ba8 | 7626 | hugetlb_vma_unlock_write(vma); |
6dfeaff9 | 7627 | /* |
1af5a810 | 7628 | * No need to call mmu_notifier_arch_invalidate_secondary_tlbs(), see |
ee65728e | 7629 | * Documentation/mm/mmu_notifier.rst. |
6dfeaff9 PX |
7630 | */ |
7631 | mmu_notifier_invalidate_range_end(&range); | |
7632 | } | |
7633 | ||
b30c14cd JH |
7634 | /* |
7635 | * This function will unconditionally remove all the shared pmd pgtable entries | |
7636 | * within the specific vma for a hugetlbfs memory range. | |
7637 | */ | |
7638 | void hugetlb_unshare_all_pmds(struct vm_area_struct *vma) | |
7639 | { | |
7640 | hugetlb_unshare_pmds(vma, ALIGN(vma->vm_start, PUD_SIZE), | |
7641 | ALIGN_DOWN(vma->vm_end, PUD_SIZE)); | |
7642 | } | |
7643 | ||
cf11e85f | 7644 | #ifdef CONFIG_CMA |
cf11e85f RG |
7645 | static bool cma_reserve_called __initdata; |
7646 | ||
7647 | static int __init cmdline_parse_hugetlb_cma(char *p) | |
7648 | { | |
38e719ab BW |
7649 | int nid, count = 0; |
7650 | unsigned long tmp; | |
7651 | char *s = p; | |
7652 | ||
7653 | while (*s) { | |
7654 | if (sscanf(s, "%lu%n", &tmp, &count) != 1) | |
7655 | break; | |
7656 | ||
7657 | if (s[count] == ':') { | |
f9317f77 | 7658 | if (tmp >= MAX_NUMNODES) |
38e719ab | 7659 | break; |
f9317f77 | 7660 | nid = array_index_nospec(tmp, MAX_NUMNODES); |
38e719ab BW |
7661 | |
7662 | s += count + 1; | |
7663 | tmp = memparse(s, &s); | |
7664 | hugetlb_cma_size_in_node[nid] = tmp; | |
7665 | hugetlb_cma_size += tmp; | |
7666 | ||
7667 | /* | |
7668 | * Skip the separator if have one, otherwise | |
7669 | * break the parsing. | |
7670 | */ | |
7671 | if (*s == ',') | |
7672 | s++; | |
7673 | else | |
7674 | break; | |
7675 | } else { | |
7676 | hugetlb_cma_size = memparse(p, &p); | |
7677 | break; | |
7678 | } | |
7679 | } | |
7680 | ||
cf11e85f RG |
7681 | return 0; |
7682 | } | |
7683 | ||
7684 | early_param("hugetlb_cma", cmdline_parse_hugetlb_cma); | |
7685 | ||
7686 | void __init hugetlb_cma_reserve(int order) | |
7687 | { | |
7688 | unsigned long size, reserved, per_node; | |
38e719ab | 7689 | bool node_specific_cma_alloc = false; |
cf11e85f RG |
7690 | int nid; |
7691 | ||
7692 | cma_reserve_called = true; | |
7693 | ||
38e719ab BW |
7694 | if (!hugetlb_cma_size) |
7695 | return; | |
7696 | ||
7697 | for (nid = 0; nid < MAX_NUMNODES; nid++) { | |
7698 | if (hugetlb_cma_size_in_node[nid] == 0) | |
7699 | continue; | |
7700 | ||
30a51400 | 7701 | if (!node_online(nid)) { |
38e719ab BW |
7702 | pr_warn("hugetlb_cma: invalid node %d specified\n", nid); |
7703 | hugetlb_cma_size -= hugetlb_cma_size_in_node[nid]; | |
7704 | hugetlb_cma_size_in_node[nid] = 0; | |
7705 | continue; | |
7706 | } | |
7707 | ||
7708 | if (hugetlb_cma_size_in_node[nid] < (PAGE_SIZE << order)) { | |
7709 | pr_warn("hugetlb_cma: cma area of node %d should be at least %lu MiB\n", | |
7710 | nid, (PAGE_SIZE << order) / SZ_1M); | |
7711 | hugetlb_cma_size -= hugetlb_cma_size_in_node[nid]; | |
7712 | hugetlb_cma_size_in_node[nid] = 0; | |
7713 | } else { | |
7714 | node_specific_cma_alloc = true; | |
7715 | } | |
7716 | } | |
7717 | ||
7718 | /* Validate the CMA size again in case some invalid nodes specified. */ | |
cf11e85f RG |
7719 | if (!hugetlb_cma_size) |
7720 | return; | |
7721 | ||
7722 | if (hugetlb_cma_size < (PAGE_SIZE << order)) { | |
7723 | pr_warn("hugetlb_cma: cma area should be at least %lu MiB\n", | |
7724 | (PAGE_SIZE << order) / SZ_1M); | |
a01f4390 | 7725 | hugetlb_cma_size = 0; |
cf11e85f RG |
7726 | return; |
7727 | } | |
7728 | ||
38e719ab BW |
7729 | if (!node_specific_cma_alloc) { |
7730 | /* | |
7731 | * If 3 GB area is requested on a machine with 4 numa nodes, | |
7732 | * let's allocate 1 GB on first three nodes and ignore the last one. | |
7733 | */ | |
7734 | per_node = DIV_ROUND_UP(hugetlb_cma_size, nr_online_nodes); | |
7735 | pr_info("hugetlb_cma: reserve %lu MiB, up to %lu MiB per node\n", | |
7736 | hugetlb_cma_size / SZ_1M, per_node / SZ_1M); | |
7737 | } | |
cf11e85f RG |
7738 | |
7739 | reserved = 0; | |
30a51400 | 7740 | for_each_online_node(nid) { |
cf11e85f | 7741 | int res; |
2281f797 | 7742 | char name[CMA_MAX_NAME]; |
cf11e85f | 7743 | |
38e719ab BW |
7744 | if (node_specific_cma_alloc) { |
7745 | if (hugetlb_cma_size_in_node[nid] == 0) | |
7746 | continue; | |
7747 | ||
7748 | size = hugetlb_cma_size_in_node[nid]; | |
7749 | } else { | |
7750 | size = min(per_node, hugetlb_cma_size - reserved); | |
7751 | } | |
7752 | ||
cf11e85f RG |
7753 | size = round_up(size, PAGE_SIZE << order); |
7754 | ||
2281f797 | 7755 | snprintf(name, sizeof(name), "hugetlb%d", nid); |
a01f4390 MK |
7756 | /* |
7757 | * Note that 'order per bit' is based on smallest size that | |
7758 | * may be returned to CMA allocator in the case of | |
7759 | * huge page demotion. | |
7760 | */ | |
7761 | res = cma_declare_contiguous_nid(0, size, 0, | |
7762 | PAGE_SIZE << HUGETLB_PAGE_ORDER, | |
29d0f41d | 7763 | 0, false, name, |
cf11e85f RG |
7764 | &hugetlb_cma[nid], nid); |
7765 | if (res) { | |
7766 | pr_warn("hugetlb_cma: reservation failed: err %d, node %d", | |
7767 | res, nid); | |
7768 | continue; | |
7769 | } | |
7770 | ||
7771 | reserved += size; | |
7772 | pr_info("hugetlb_cma: reserved %lu MiB on node %d\n", | |
7773 | size / SZ_1M, nid); | |
7774 | ||
7775 | if (reserved >= hugetlb_cma_size) | |
7776 | break; | |
7777 | } | |
a01f4390 MK |
7778 | |
7779 | if (!reserved) | |
7780 | /* | |
7781 | * hugetlb_cma_size is used to determine if allocations from | |
7782 | * cma are possible. Set to zero if no cma regions are set up. | |
7783 | */ | |
7784 | hugetlb_cma_size = 0; | |
cf11e85f RG |
7785 | } |
7786 | ||
263b8998 | 7787 | static void __init hugetlb_cma_check(void) |
cf11e85f RG |
7788 | { |
7789 | if (!hugetlb_cma_size || cma_reserve_called) | |
7790 | return; | |
7791 | ||
7792 | pr_warn("hugetlb_cma: the option isn't supported by current arch\n"); | |
7793 | } | |
7794 | ||
7795 | #endif /* CONFIG_CMA */ |