Commit | Line | Data |
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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> |
d6606683 | 34 | |
63551ae0 | 35 | #include <asm/page.h> |
ca15ca40 | 36 | #include <asm/pgalloc.h> |
24669e58 | 37 | #include <asm/tlb.h> |
63551ae0 | 38 | |
24669e58 | 39 | #include <linux/io.h> |
63551ae0 | 40 | #include <linux/hugetlb.h> |
9dd540e2 | 41 | #include <linux/hugetlb_cgroup.h> |
9a305230 | 42 | #include <linux/node.h> |
ab5ac90a | 43 | #include <linux/page_owner.h> |
7835e98b | 44 | #include "internal.h" |
f41f2ed4 | 45 | #include "hugetlb_vmemmap.h" |
1da177e4 | 46 | |
c3f38a38 | 47 | int hugetlb_max_hstate __read_mostly; |
e5ff2159 AK |
48 | unsigned int default_hstate_idx; |
49 | struct hstate hstates[HUGE_MAX_HSTATE]; | |
cf11e85f | 50 | |
dbda8fea | 51 | #ifdef CONFIG_CMA |
cf11e85f | 52 | static struct cma *hugetlb_cma[MAX_NUMNODES]; |
dbda8fea BS |
53 | #endif |
54 | static unsigned long hugetlb_cma_size __initdata; | |
cf11e85f | 55 | |
641844f5 NH |
56 | /* |
57 | * Minimum page order among possible hugepage sizes, set to a proper value | |
58 | * at boot time. | |
59 | */ | |
60 | static unsigned int minimum_order __read_mostly = UINT_MAX; | |
e5ff2159 | 61 | |
53ba51d2 JT |
62 | __initdata LIST_HEAD(huge_boot_pages); |
63 | ||
e5ff2159 AK |
64 | /* for command line parsing */ |
65 | static struct hstate * __initdata parsed_hstate; | |
66 | static unsigned long __initdata default_hstate_max_huge_pages; | |
9fee021d | 67 | static bool __initdata parsed_valid_hugepagesz = true; |
282f4214 | 68 | static bool __initdata parsed_default_hugepagesz; |
e5ff2159 | 69 | |
3935baa9 | 70 | /* |
31caf665 NH |
71 | * Protects updates to hugepage_freelists, hugepage_activelist, nr_huge_pages, |
72 | * free_huge_pages, and surplus_huge_pages. | |
3935baa9 | 73 | */ |
c3f38a38 | 74 | DEFINE_SPINLOCK(hugetlb_lock); |
0bd0f9fb | 75 | |
8382d914 DB |
76 | /* |
77 | * Serializes faults on the same logical page. This is used to | |
78 | * prevent spurious OOMs when the hugepage pool is fully utilized. | |
79 | */ | |
80 | static int num_fault_mutexes; | |
c672c7f2 | 81 | struct mutex *hugetlb_fault_mutex_table ____cacheline_aligned_in_smp; |
8382d914 | 82 | |
7ca02d0a MK |
83 | /* Forward declaration */ |
84 | static int hugetlb_acct_memory(struct hstate *h, long delta); | |
85 | ||
1d88433b | 86 | static inline bool subpool_is_free(struct hugepage_subpool *spool) |
90481622 | 87 | { |
1d88433b ML |
88 | if (spool->count) |
89 | return false; | |
90 | if (spool->max_hpages != -1) | |
91 | return spool->used_hpages == 0; | |
92 | if (spool->min_hpages != -1) | |
93 | return spool->rsv_hpages == spool->min_hpages; | |
94 | ||
95 | return true; | |
96 | } | |
90481622 | 97 | |
db71ef79 MK |
98 | static inline void unlock_or_release_subpool(struct hugepage_subpool *spool, |
99 | unsigned long irq_flags) | |
1d88433b | 100 | { |
db71ef79 | 101 | spin_unlock_irqrestore(&spool->lock, irq_flags); |
90481622 DG |
102 | |
103 | /* If no pages are used, and no other handles to the subpool | |
7c8de358 | 104 | * remain, give up any reservations based on minimum size and |
7ca02d0a | 105 | * free the subpool */ |
1d88433b | 106 | if (subpool_is_free(spool)) { |
7ca02d0a MK |
107 | if (spool->min_hpages != -1) |
108 | hugetlb_acct_memory(spool->hstate, | |
109 | -spool->min_hpages); | |
90481622 | 110 | kfree(spool); |
7ca02d0a | 111 | } |
90481622 DG |
112 | } |
113 | ||
7ca02d0a MK |
114 | struct hugepage_subpool *hugepage_new_subpool(struct hstate *h, long max_hpages, |
115 | long min_hpages) | |
90481622 DG |
116 | { |
117 | struct hugepage_subpool *spool; | |
118 | ||
c6a91820 | 119 | spool = kzalloc(sizeof(*spool), GFP_KERNEL); |
90481622 DG |
120 | if (!spool) |
121 | return NULL; | |
122 | ||
123 | spin_lock_init(&spool->lock); | |
124 | spool->count = 1; | |
7ca02d0a MK |
125 | spool->max_hpages = max_hpages; |
126 | spool->hstate = h; | |
127 | spool->min_hpages = min_hpages; | |
128 | ||
129 | if (min_hpages != -1 && hugetlb_acct_memory(h, min_hpages)) { | |
130 | kfree(spool); | |
131 | return NULL; | |
132 | } | |
133 | spool->rsv_hpages = min_hpages; | |
90481622 DG |
134 | |
135 | return spool; | |
136 | } | |
137 | ||
138 | void hugepage_put_subpool(struct hugepage_subpool *spool) | |
139 | { | |
db71ef79 MK |
140 | unsigned long flags; |
141 | ||
142 | spin_lock_irqsave(&spool->lock, flags); | |
90481622 DG |
143 | BUG_ON(!spool->count); |
144 | spool->count--; | |
db71ef79 | 145 | unlock_or_release_subpool(spool, flags); |
90481622 DG |
146 | } |
147 | ||
1c5ecae3 MK |
148 | /* |
149 | * Subpool accounting for allocating and reserving pages. | |
150 | * Return -ENOMEM if there are not enough resources to satisfy the | |
9e7ee400 | 151 | * request. Otherwise, return the number of pages by which the |
1c5ecae3 MK |
152 | * global pools must be adjusted (upward). The returned value may |
153 | * only be different than the passed value (delta) in the case where | |
7c8de358 | 154 | * a subpool minimum size must be maintained. |
1c5ecae3 MK |
155 | */ |
156 | static long hugepage_subpool_get_pages(struct hugepage_subpool *spool, | |
90481622 DG |
157 | long delta) |
158 | { | |
1c5ecae3 | 159 | long ret = delta; |
90481622 DG |
160 | |
161 | if (!spool) | |
1c5ecae3 | 162 | return ret; |
90481622 | 163 | |
db71ef79 | 164 | spin_lock_irq(&spool->lock); |
1c5ecae3 MK |
165 | |
166 | if (spool->max_hpages != -1) { /* maximum size accounting */ | |
167 | if ((spool->used_hpages + delta) <= spool->max_hpages) | |
168 | spool->used_hpages += delta; | |
169 | else { | |
170 | ret = -ENOMEM; | |
171 | goto unlock_ret; | |
172 | } | |
90481622 | 173 | } |
90481622 | 174 | |
09a95e29 MK |
175 | /* minimum size accounting */ |
176 | if (spool->min_hpages != -1 && spool->rsv_hpages) { | |
1c5ecae3 MK |
177 | if (delta > spool->rsv_hpages) { |
178 | /* | |
179 | * Asking for more reserves than those already taken on | |
180 | * behalf of subpool. Return difference. | |
181 | */ | |
182 | ret = delta - spool->rsv_hpages; | |
183 | spool->rsv_hpages = 0; | |
184 | } else { | |
185 | ret = 0; /* reserves already accounted for */ | |
186 | spool->rsv_hpages -= delta; | |
187 | } | |
188 | } | |
189 | ||
190 | unlock_ret: | |
db71ef79 | 191 | spin_unlock_irq(&spool->lock); |
90481622 DG |
192 | return ret; |
193 | } | |
194 | ||
1c5ecae3 MK |
195 | /* |
196 | * Subpool accounting for freeing and unreserving pages. | |
197 | * Return the number of global page reservations that must be dropped. | |
198 | * The return value may only be different than the passed value (delta) | |
199 | * in the case where a subpool minimum size must be maintained. | |
200 | */ | |
201 | static long hugepage_subpool_put_pages(struct hugepage_subpool *spool, | |
90481622 DG |
202 | long delta) |
203 | { | |
1c5ecae3 | 204 | long ret = delta; |
db71ef79 | 205 | unsigned long flags; |
1c5ecae3 | 206 | |
90481622 | 207 | if (!spool) |
1c5ecae3 | 208 | return delta; |
90481622 | 209 | |
db71ef79 | 210 | spin_lock_irqsave(&spool->lock, flags); |
1c5ecae3 MK |
211 | |
212 | if (spool->max_hpages != -1) /* maximum size accounting */ | |
213 | spool->used_hpages -= delta; | |
214 | ||
09a95e29 MK |
215 | /* minimum size accounting */ |
216 | if (spool->min_hpages != -1 && spool->used_hpages < spool->min_hpages) { | |
1c5ecae3 MK |
217 | if (spool->rsv_hpages + delta <= spool->min_hpages) |
218 | ret = 0; | |
219 | else | |
220 | ret = spool->rsv_hpages + delta - spool->min_hpages; | |
221 | ||
222 | spool->rsv_hpages += delta; | |
223 | if (spool->rsv_hpages > spool->min_hpages) | |
224 | spool->rsv_hpages = spool->min_hpages; | |
225 | } | |
226 | ||
227 | /* | |
228 | * If hugetlbfs_put_super couldn't free spool due to an outstanding | |
229 | * quota reference, free it now. | |
230 | */ | |
db71ef79 | 231 | unlock_or_release_subpool(spool, flags); |
1c5ecae3 MK |
232 | |
233 | return ret; | |
90481622 DG |
234 | } |
235 | ||
236 | static inline struct hugepage_subpool *subpool_inode(struct inode *inode) | |
237 | { | |
238 | return HUGETLBFS_SB(inode->i_sb)->spool; | |
239 | } | |
240 | ||
241 | static inline struct hugepage_subpool *subpool_vma(struct vm_area_struct *vma) | |
242 | { | |
496ad9aa | 243 | return subpool_inode(file_inode(vma->vm_file)); |
90481622 DG |
244 | } |
245 | ||
0db9d74e MA |
246 | /* Helper that removes a struct file_region from the resv_map cache and returns |
247 | * it for use. | |
248 | */ | |
249 | static struct file_region * | |
250 | get_file_region_entry_from_cache(struct resv_map *resv, long from, long to) | |
251 | { | |
252 | struct file_region *nrg = NULL; | |
253 | ||
254 | VM_BUG_ON(resv->region_cache_count <= 0); | |
255 | ||
256 | resv->region_cache_count--; | |
257 | nrg = list_first_entry(&resv->region_cache, struct file_region, link); | |
0db9d74e MA |
258 | list_del(&nrg->link); |
259 | ||
260 | nrg->from = from; | |
261 | nrg->to = to; | |
262 | ||
263 | return nrg; | |
264 | } | |
265 | ||
075a61d0 MA |
266 | static void copy_hugetlb_cgroup_uncharge_info(struct file_region *nrg, |
267 | struct file_region *rg) | |
268 | { | |
269 | #ifdef CONFIG_CGROUP_HUGETLB | |
270 | nrg->reservation_counter = rg->reservation_counter; | |
271 | nrg->css = rg->css; | |
272 | if (rg->css) | |
273 | css_get(rg->css); | |
274 | #endif | |
275 | } | |
276 | ||
277 | /* Helper that records hugetlb_cgroup uncharge info. */ | |
278 | static void record_hugetlb_cgroup_uncharge_info(struct hugetlb_cgroup *h_cg, | |
279 | struct hstate *h, | |
280 | struct resv_map *resv, | |
281 | struct file_region *nrg) | |
282 | { | |
283 | #ifdef CONFIG_CGROUP_HUGETLB | |
284 | if (h_cg) { | |
285 | nrg->reservation_counter = | |
286 | &h_cg->rsvd_hugepage[hstate_index(h)]; | |
287 | nrg->css = &h_cg->css; | |
d85aecf2 ML |
288 | /* |
289 | * The caller will hold exactly one h_cg->css reference for the | |
290 | * whole contiguous reservation region. But this area might be | |
291 | * scattered when there are already some file_regions reside in | |
292 | * it. As a result, many file_regions may share only one css | |
293 | * reference. In order to ensure that one file_region must hold | |
294 | * exactly one h_cg->css reference, we should do css_get for | |
295 | * each file_region and leave the reference held by caller | |
296 | * untouched. | |
297 | */ | |
298 | css_get(&h_cg->css); | |
075a61d0 MA |
299 | if (!resv->pages_per_hpage) |
300 | resv->pages_per_hpage = pages_per_huge_page(h); | |
301 | /* pages_per_hpage should be the same for all entries in | |
302 | * a resv_map. | |
303 | */ | |
304 | VM_BUG_ON(resv->pages_per_hpage != pages_per_huge_page(h)); | |
305 | } else { | |
306 | nrg->reservation_counter = NULL; | |
307 | nrg->css = NULL; | |
308 | } | |
309 | #endif | |
310 | } | |
311 | ||
d85aecf2 ML |
312 | static void put_uncharge_info(struct file_region *rg) |
313 | { | |
314 | #ifdef CONFIG_CGROUP_HUGETLB | |
315 | if (rg->css) | |
316 | css_put(rg->css); | |
317 | #endif | |
318 | } | |
319 | ||
a9b3f867 MA |
320 | static bool has_same_uncharge_info(struct file_region *rg, |
321 | struct file_region *org) | |
322 | { | |
323 | #ifdef CONFIG_CGROUP_HUGETLB | |
324 | return rg && org && | |
325 | rg->reservation_counter == org->reservation_counter && | |
326 | rg->css == org->css; | |
327 | ||
328 | #else | |
329 | return true; | |
330 | #endif | |
331 | } | |
332 | ||
333 | static void coalesce_file_region(struct resv_map *resv, struct file_region *rg) | |
334 | { | |
335 | struct file_region *nrg = NULL, *prg = NULL; | |
336 | ||
337 | prg = list_prev_entry(rg, link); | |
338 | if (&prg->link != &resv->regions && prg->to == rg->from && | |
339 | has_same_uncharge_info(prg, rg)) { | |
340 | prg->to = rg->to; | |
341 | ||
342 | list_del(&rg->link); | |
d85aecf2 | 343 | put_uncharge_info(rg); |
a9b3f867 MA |
344 | kfree(rg); |
345 | ||
7db5e7b6 | 346 | rg = prg; |
a9b3f867 MA |
347 | } |
348 | ||
349 | nrg = list_next_entry(rg, link); | |
350 | if (&nrg->link != &resv->regions && nrg->from == rg->to && | |
351 | has_same_uncharge_info(nrg, rg)) { | |
352 | nrg->from = rg->from; | |
353 | ||
354 | list_del(&rg->link); | |
d85aecf2 | 355 | put_uncharge_info(rg); |
a9b3f867 | 356 | kfree(rg); |
a9b3f867 MA |
357 | } |
358 | } | |
359 | ||
2103cf9c PX |
360 | static inline long |
361 | hugetlb_resv_map_add(struct resv_map *map, struct file_region *rg, long from, | |
362 | long to, struct hstate *h, struct hugetlb_cgroup *cg, | |
363 | long *regions_needed) | |
364 | { | |
365 | struct file_region *nrg; | |
366 | ||
367 | if (!regions_needed) { | |
368 | nrg = get_file_region_entry_from_cache(map, from, to); | |
369 | record_hugetlb_cgroup_uncharge_info(cg, h, map, nrg); | |
370 | list_add(&nrg->link, rg->link.prev); | |
371 | coalesce_file_region(map, nrg); | |
372 | } else | |
373 | *regions_needed += 1; | |
374 | ||
375 | return to - from; | |
376 | } | |
377 | ||
972a3da3 WY |
378 | /* |
379 | * Must be called with resv->lock held. | |
380 | * | |
381 | * Calling this with regions_needed != NULL will count the number of pages | |
382 | * to be added but will not modify the linked list. And regions_needed will | |
383 | * indicate the number of file_regions needed in the cache to carry out to add | |
384 | * the regions for this range. | |
d75c6af9 MA |
385 | */ |
386 | static long add_reservation_in_range(struct resv_map *resv, long f, long t, | |
075a61d0 | 387 | struct hugetlb_cgroup *h_cg, |
972a3da3 | 388 | struct hstate *h, long *regions_needed) |
d75c6af9 | 389 | { |
0db9d74e | 390 | long add = 0; |
d75c6af9 | 391 | struct list_head *head = &resv->regions; |
0db9d74e | 392 | long last_accounted_offset = f; |
2103cf9c | 393 | struct file_region *rg = NULL, *trg = NULL; |
d75c6af9 | 394 | |
0db9d74e MA |
395 | if (regions_needed) |
396 | *regions_needed = 0; | |
d75c6af9 | 397 | |
0db9d74e MA |
398 | /* In this loop, we essentially handle an entry for the range |
399 | * [last_accounted_offset, rg->from), at every iteration, with some | |
400 | * bounds checking. | |
401 | */ | |
402 | list_for_each_entry_safe(rg, trg, head, link) { | |
403 | /* Skip irrelevant regions that start before our range. */ | |
404 | if (rg->from < f) { | |
405 | /* If this region ends after the last accounted offset, | |
406 | * then we need to update last_accounted_offset. | |
407 | */ | |
408 | if (rg->to > last_accounted_offset) | |
409 | last_accounted_offset = rg->to; | |
410 | continue; | |
411 | } | |
d75c6af9 | 412 | |
0db9d74e MA |
413 | /* When we find a region that starts beyond our range, we've |
414 | * finished. | |
415 | */ | |
ca7e0457 | 416 | if (rg->from >= t) |
d75c6af9 MA |
417 | break; |
418 | ||
0db9d74e MA |
419 | /* Add an entry for last_accounted_offset -> rg->from, and |
420 | * update last_accounted_offset. | |
421 | */ | |
2103cf9c PX |
422 | if (rg->from > last_accounted_offset) |
423 | add += hugetlb_resv_map_add(resv, rg, | |
424 | last_accounted_offset, | |
425 | rg->from, h, h_cg, | |
426 | regions_needed); | |
0db9d74e MA |
427 | |
428 | last_accounted_offset = rg->to; | |
429 | } | |
430 | ||
431 | /* Handle the case where our range extends beyond | |
432 | * last_accounted_offset. | |
433 | */ | |
2103cf9c PX |
434 | if (last_accounted_offset < t) |
435 | add += hugetlb_resv_map_add(resv, rg, last_accounted_offset, | |
436 | t, h, h_cg, regions_needed); | |
0db9d74e MA |
437 | |
438 | VM_BUG_ON(add < 0); | |
439 | return add; | |
440 | } | |
441 | ||
442 | /* Must be called with resv->lock acquired. Will drop lock to allocate entries. | |
443 | */ | |
444 | static int allocate_file_region_entries(struct resv_map *resv, | |
445 | int regions_needed) | |
446 | __must_hold(&resv->lock) | |
447 | { | |
448 | struct list_head allocated_regions; | |
449 | int to_allocate = 0, i = 0; | |
450 | struct file_region *trg = NULL, *rg = NULL; | |
451 | ||
452 | VM_BUG_ON(regions_needed < 0); | |
453 | ||
454 | INIT_LIST_HEAD(&allocated_regions); | |
455 | ||
456 | /* | |
457 | * Check for sufficient descriptors in the cache to accommodate | |
458 | * the number of in progress add operations plus regions_needed. | |
459 | * | |
460 | * This is a while loop because when we drop the lock, some other call | |
461 | * to region_add or region_del may have consumed some region_entries, | |
462 | * so we keep looping here until we finally have enough entries for | |
463 | * (adds_in_progress + regions_needed). | |
464 | */ | |
465 | while (resv->region_cache_count < | |
466 | (resv->adds_in_progress + regions_needed)) { | |
467 | to_allocate = resv->adds_in_progress + regions_needed - | |
468 | resv->region_cache_count; | |
469 | ||
470 | /* At this point, we should have enough entries in the cache | |
f0953a1b | 471 | * for all the existing adds_in_progress. We should only be |
0db9d74e | 472 | * needing to allocate for regions_needed. |
d75c6af9 | 473 | */ |
0db9d74e MA |
474 | VM_BUG_ON(resv->region_cache_count < resv->adds_in_progress); |
475 | ||
476 | spin_unlock(&resv->lock); | |
477 | for (i = 0; i < to_allocate; i++) { | |
478 | trg = kmalloc(sizeof(*trg), GFP_KERNEL); | |
479 | if (!trg) | |
480 | goto out_of_memory; | |
481 | list_add(&trg->link, &allocated_regions); | |
d75c6af9 | 482 | } |
d75c6af9 | 483 | |
0db9d74e MA |
484 | spin_lock(&resv->lock); |
485 | ||
d3ec7b6e WY |
486 | list_splice(&allocated_regions, &resv->region_cache); |
487 | resv->region_cache_count += to_allocate; | |
d75c6af9 MA |
488 | } |
489 | ||
0db9d74e | 490 | return 0; |
d75c6af9 | 491 | |
0db9d74e MA |
492 | out_of_memory: |
493 | list_for_each_entry_safe(rg, trg, &allocated_regions, link) { | |
494 | list_del(&rg->link); | |
495 | kfree(rg); | |
496 | } | |
497 | return -ENOMEM; | |
d75c6af9 MA |
498 | } |
499 | ||
1dd308a7 MK |
500 | /* |
501 | * Add the huge page range represented by [f, t) to the reserve | |
0db9d74e MA |
502 | * map. Regions will be taken from the cache to fill in this range. |
503 | * Sufficient regions should exist in the cache due to the previous | |
504 | * call to region_chg with the same range, but in some cases the cache will not | |
505 | * have sufficient entries due to races with other code doing region_add or | |
506 | * region_del. The extra needed entries will be allocated. | |
cf3ad20b | 507 | * |
0db9d74e MA |
508 | * regions_needed is the out value provided by a previous call to region_chg. |
509 | * | |
510 | * Return the number of new huge pages added to the map. This number is greater | |
511 | * than or equal to zero. If file_region entries needed to be allocated for | |
7c8de358 | 512 | * this operation and we were not able to allocate, it returns -ENOMEM. |
0db9d74e MA |
513 | * region_add of regions of length 1 never allocate file_regions and cannot |
514 | * fail; region_chg will always allocate at least 1 entry and a region_add for | |
515 | * 1 page will only require at most 1 entry. | |
1dd308a7 | 516 | */ |
0db9d74e | 517 | static long region_add(struct resv_map *resv, long f, long t, |
075a61d0 MA |
518 | long in_regions_needed, struct hstate *h, |
519 | struct hugetlb_cgroup *h_cg) | |
96822904 | 520 | { |
0db9d74e | 521 | long add = 0, actual_regions_needed = 0; |
96822904 | 522 | |
7b24d861 | 523 | spin_lock(&resv->lock); |
0db9d74e MA |
524 | retry: |
525 | ||
526 | /* Count how many regions are actually needed to execute this add. */ | |
972a3da3 WY |
527 | add_reservation_in_range(resv, f, t, NULL, NULL, |
528 | &actual_regions_needed); | |
96822904 | 529 | |
5e911373 | 530 | /* |
0db9d74e MA |
531 | * Check for sufficient descriptors in the cache to accommodate |
532 | * this add operation. Note that actual_regions_needed may be greater | |
533 | * than in_regions_needed, as the resv_map may have been modified since | |
534 | * the region_chg call. In this case, we need to make sure that we | |
535 | * allocate extra entries, such that we have enough for all the | |
536 | * existing adds_in_progress, plus the excess needed for this | |
537 | * operation. | |
5e911373 | 538 | */ |
0db9d74e MA |
539 | if (actual_regions_needed > in_regions_needed && |
540 | resv->region_cache_count < | |
541 | resv->adds_in_progress + | |
542 | (actual_regions_needed - in_regions_needed)) { | |
543 | /* region_add operation of range 1 should never need to | |
544 | * allocate file_region entries. | |
545 | */ | |
546 | VM_BUG_ON(t - f <= 1); | |
5e911373 | 547 | |
0db9d74e MA |
548 | if (allocate_file_region_entries( |
549 | resv, actual_regions_needed - in_regions_needed)) { | |
550 | return -ENOMEM; | |
551 | } | |
5e911373 | 552 | |
0db9d74e | 553 | goto retry; |
5e911373 MK |
554 | } |
555 | ||
972a3da3 | 556 | add = add_reservation_in_range(resv, f, t, h_cg, h, NULL); |
0db9d74e MA |
557 | |
558 | resv->adds_in_progress -= in_regions_needed; | |
cf3ad20b | 559 | |
7b24d861 | 560 | spin_unlock(&resv->lock); |
cf3ad20b | 561 | return add; |
96822904 AW |
562 | } |
563 | ||
1dd308a7 MK |
564 | /* |
565 | * Examine the existing reserve map and determine how many | |
566 | * huge pages in the specified range [f, t) are NOT currently | |
567 | * represented. This routine is called before a subsequent | |
568 | * call to region_add that will actually modify the reserve | |
569 | * map to add the specified range [f, t). region_chg does | |
570 | * not change the number of huge pages represented by the | |
0db9d74e MA |
571 | * map. A number of new file_region structures is added to the cache as a |
572 | * placeholder, for the subsequent region_add call to use. At least 1 | |
573 | * file_region structure is added. | |
574 | * | |
575 | * out_regions_needed is the number of regions added to the | |
576 | * resv->adds_in_progress. This value needs to be provided to a follow up call | |
577 | * to region_add or region_abort for proper accounting. | |
5e911373 MK |
578 | * |
579 | * Returns the number of huge pages that need to be added to the existing | |
580 | * reservation map for the range [f, t). This number is greater or equal to | |
581 | * zero. -ENOMEM is returned if a new file_region structure or cache entry | |
582 | * is needed and can not be allocated. | |
1dd308a7 | 583 | */ |
0db9d74e MA |
584 | static long region_chg(struct resv_map *resv, long f, long t, |
585 | long *out_regions_needed) | |
96822904 | 586 | { |
96822904 AW |
587 | long chg = 0; |
588 | ||
7b24d861 | 589 | spin_lock(&resv->lock); |
5e911373 | 590 | |
972a3da3 | 591 | /* Count how many hugepages in this range are NOT represented. */ |
075a61d0 | 592 | chg = add_reservation_in_range(resv, f, t, NULL, NULL, |
972a3da3 | 593 | out_regions_needed); |
5e911373 | 594 | |
0db9d74e MA |
595 | if (*out_regions_needed == 0) |
596 | *out_regions_needed = 1; | |
5e911373 | 597 | |
0db9d74e MA |
598 | if (allocate_file_region_entries(resv, *out_regions_needed)) |
599 | return -ENOMEM; | |
5e911373 | 600 | |
0db9d74e | 601 | resv->adds_in_progress += *out_regions_needed; |
7b24d861 | 602 | |
7b24d861 | 603 | spin_unlock(&resv->lock); |
96822904 AW |
604 | return chg; |
605 | } | |
606 | ||
5e911373 MK |
607 | /* |
608 | * Abort the in progress add operation. The adds_in_progress field | |
609 | * of the resv_map keeps track of the operations in progress between | |
610 | * calls to region_chg and region_add. Operations are sometimes | |
611 | * aborted after the call to region_chg. In such cases, region_abort | |
0db9d74e MA |
612 | * is called to decrement the adds_in_progress counter. regions_needed |
613 | * is the value returned by the region_chg call, it is used to decrement | |
614 | * the adds_in_progress counter. | |
5e911373 MK |
615 | * |
616 | * NOTE: The range arguments [f, t) are not needed or used in this | |
617 | * routine. They are kept to make reading the calling code easier as | |
618 | * arguments will match the associated region_chg call. | |
619 | */ | |
0db9d74e MA |
620 | static void region_abort(struct resv_map *resv, long f, long t, |
621 | long regions_needed) | |
5e911373 MK |
622 | { |
623 | spin_lock(&resv->lock); | |
624 | VM_BUG_ON(!resv->region_cache_count); | |
0db9d74e | 625 | resv->adds_in_progress -= regions_needed; |
5e911373 MK |
626 | spin_unlock(&resv->lock); |
627 | } | |
628 | ||
1dd308a7 | 629 | /* |
feba16e2 MK |
630 | * Delete the specified range [f, t) from the reserve map. If the |
631 | * t parameter is LONG_MAX, this indicates that ALL regions after f | |
632 | * should be deleted. Locate the regions which intersect [f, t) | |
633 | * and either trim, delete or split the existing regions. | |
634 | * | |
635 | * Returns the number of huge pages deleted from the reserve map. | |
636 | * In the normal case, the return value is zero or more. In the | |
637 | * case where a region must be split, a new region descriptor must | |
638 | * be allocated. If the allocation fails, -ENOMEM will be returned. | |
639 | * NOTE: If the parameter t == LONG_MAX, then we will never split | |
640 | * a region and possibly return -ENOMEM. Callers specifying | |
641 | * t == LONG_MAX do not need to check for -ENOMEM error. | |
1dd308a7 | 642 | */ |
feba16e2 | 643 | static long region_del(struct resv_map *resv, long f, long t) |
96822904 | 644 | { |
1406ec9b | 645 | struct list_head *head = &resv->regions; |
96822904 | 646 | struct file_region *rg, *trg; |
feba16e2 MK |
647 | struct file_region *nrg = NULL; |
648 | long del = 0; | |
96822904 | 649 | |
feba16e2 | 650 | retry: |
7b24d861 | 651 | spin_lock(&resv->lock); |
feba16e2 | 652 | list_for_each_entry_safe(rg, trg, head, link) { |
dbe409e4 MK |
653 | /* |
654 | * Skip regions before the range to be deleted. file_region | |
655 | * ranges are normally of the form [from, to). However, there | |
656 | * may be a "placeholder" entry in the map which is of the form | |
657 | * (from, to) with from == to. Check for placeholder entries | |
658 | * at the beginning of the range to be deleted. | |
659 | */ | |
660 | if (rg->to <= f && (rg->to != rg->from || rg->to != f)) | |
feba16e2 | 661 | continue; |
dbe409e4 | 662 | |
feba16e2 | 663 | if (rg->from >= t) |
96822904 | 664 | break; |
96822904 | 665 | |
feba16e2 MK |
666 | if (f > rg->from && t < rg->to) { /* Must split region */ |
667 | /* | |
668 | * Check for an entry in the cache before dropping | |
669 | * lock and attempting allocation. | |
670 | */ | |
671 | if (!nrg && | |
672 | resv->region_cache_count > resv->adds_in_progress) { | |
673 | nrg = list_first_entry(&resv->region_cache, | |
674 | struct file_region, | |
675 | link); | |
676 | list_del(&nrg->link); | |
677 | resv->region_cache_count--; | |
678 | } | |
96822904 | 679 | |
feba16e2 MK |
680 | if (!nrg) { |
681 | spin_unlock(&resv->lock); | |
682 | nrg = kmalloc(sizeof(*nrg), GFP_KERNEL); | |
683 | if (!nrg) | |
684 | return -ENOMEM; | |
685 | goto retry; | |
686 | } | |
687 | ||
688 | del += t - f; | |
79aa925b | 689 | hugetlb_cgroup_uncharge_file_region( |
d85aecf2 | 690 | resv, rg, t - f, false); |
feba16e2 MK |
691 | |
692 | /* New entry for end of split region */ | |
693 | nrg->from = t; | |
694 | nrg->to = rg->to; | |
075a61d0 MA |
695 | |
696 | copy_hugetlb_cgroup_uncharge_info(nrg, rg); | |
697 | ||
feba16e2 MK |
698 | INIT_LIST_HEAD(&nrg->link); |
699 | ||
700 | /* Original entry is trimmed */ | |
701 | rg->to = f; | |
702 | ||
703 | list_add(&nrg->link, &rg->link); | |
704 | nrg = NULL; | |
96822904 | 705 | break; |
feba16e2 MK |
706 | } |
707 | ||
708 | if (f <= rg->from && t >= rg->to) { /* Remove entire region */ | |
709 | del += rg->to - rg->from; | |
075a61d0 | 710 | hugetlb_cgroup_uncharge_file_region(resv, rg, |
d85aecf2 | 711 | rg->to - rg->from, true); |
feba16e2 MK |
712 | list_del(&rg->link); |
713 | kfree(rg); | |
714 | continue; | |
715 | } | |
716 | ||
717 | if (f <= rg->from) { /* Trim beginning of region */ | |
075a61d0 | 718 | hugetlb_cgroup_uncharge_file_region(resv, rg, |
d85aecf2 | 719 | t - rg->from, false); |
075a61d0 | 720 | |
79aa925b MK |
721 | del += t - rg->from; |
722 | rg->from = t; | |
723 | } else { /* Trim end of region */ | |
075a61d0 | 724 | hugetlb_cgroup_uncharge_file_region(resv, rg, |
d85aecf2 | 725 | rg->to - f, false); |
79aa925b MK |
726 | |
727 | del += rg->to - f; | |
728 | rg->to = f; | |
feba16e2 | 729 | } |
96822904 | 730 | } |
7b24d861 | 731 | |
7b24d861 | 732 | spin_unlock(&resv->lock); |
feba16e2 MK |
733 | kfree(nrg); |
734 | return del; | |
96822904 AW |
735 | } |
736 | ||
b5cec28d MK |
737 | /* |
738 | * A rare out of memory error was encountered which prevented removal of | |
739 | * the reserve map region for a page. The huge page itself was free'ed | |
740 | * and removed from the page cache. This routine will adjust the subpool | |
741 | * usage count, and the global reserve count if needed. By incrementing | |
742 | * these counts, the reserve map entry which could not be deleted will | |
743 | * appear as a "reserved" entry instead of simply dangling with incorrect | |
744 | * counts. | |
745 | */ | |
72e2936c | 746 | void hugetlb_fix_reserve_counts(struct inode *inode) |
b5cec28d MK |
747 | { |
748 | struct hugepage_subpool *spool = subpool_inode(inode); | |
749 | long rsv_adjust; | |
da56388c | 750 | bool reserved = false; |
b5cec28d MK |
751 | |
752 | rsv_adjust = hugepage_subpool_get_pages(spool, 1); | |
da56388c | 753 | if (rsv_adjust > 0) { |
b5cec28d MK |
754 | struct hstate *h = hstate_inode(inode); |
755 | ||
da56388c ML |
756 | if (!hugetlb_acct_memory(h, 1)) |
757 | reserved = true; | |
758 | } else if (!rsv_adjust) { | |
759 | reserved = true; | |
b5cec28d | 760 | } |
da56388c ML |
761 | |
762 | if (!reserved) | |
763 | pr_warn("hugetlb: Huge Page Reserved count may go negative.\n"); | |
b5cec28d MK |
764 | } |
765 | ||
1dd308a7 MK |
766 | /* |
767 | * Count and return the number of huge pages in the reserve map | |
768 | * that intersect with the range [f, t). | |
769 | */ | |
1406ec9b | 770 | static long region_count(struct resv_map *resv, long f, long t) |
84afd99b | 771 | { |
1406ec9b | 772 | struct list_head *head = &resv->regions; |
84afd99b AW |
773 | struct file_region *rg; |
774 | long chg = 0; | |
775 | ||
7b24d861 | 776 | spin_lock(&resv->lock); |
84afd99b AW |
777 | /* Locate each segment we overlap with, and count that overlap. */ |
778 | list_for_each_entry(rg, head, link) { | |
f2135a4a WSH |
779 | long seg_from; |
780 | long seg_to; | |
84afd99b AW |
781 | |
782 | if (rg->to <= f) | |
783 | continue; | |
784 | if (rg->from >= t) | |
785 | break; | |
786 | ||
787 | seg_from = max(rg->from, f); | |
788 | seg_to = min(rg->to, t); | |
789 | ||
790 | chg += seg_to - seg_from; | |
791 | } | |
7b24d861 | 792 | spin_unlock(&resv->lock); |
84afd99b AW |
793 | |
794 | return chg; | |
795 | } | |
796 | ||
e7c4b0bf AW |
797 | /* |
798 | * Convert the address within this vma to the page offset within | |
799 | * the mapping, in pagecache page units; huge pages here. | |
800 | */ | |
a5516438 AK |
801 | static pgoff_t vma_hugecache_offset(struct hstate *h, |
802 | struct vm_area_struct *vma, unsigned long address) | |
e7c4b0bf | 803 | { |
a5516438 AK |
804 | return ((address - vma->vm_start) >> huge_page_shift(h)) + |
805 | (vma->vm_pgoff >> huge_page_order(h)); | |
e7c4b0bf AW |
806 | } |
807 | ||
0fe6e20b NH |
808 | pgoff_t linear_hugepage_index(struct vm_area_struct *vma, |
809 | unsigned long address) | |
810 | { | |
811 | return vma_hugecache_offset(hstate_vma(vma), vma, address); | |
812 | } | |
dee41079 | 813 | EXPORT_SYMBOL_GPL(linear_hugepage_index); |
0fe6e20b | 814 | |
08fba699 MG |
815 | /* |
816 | * Return the size of the pages allocated when backing a VMA. In the majority | |
817 | * cases this will be same size as used by the page table entries. | |
818 | */ | |
819 | unsigned long vma_kernel_pagesize(struct vm_area_struct *vma) | |
820 | { | |
05ea8860 DW |
821 | if (vma->vm_ops && vma->vm_ops->pagesize) |
822 | return vma->vm_ops->pagesize(vma); | |
823 | return PAGE_SIZE; | |
08fba699 | 824 | } |
f340ca0f | 825 | EXPORT_SYMBOL_GPL(vma_kernel_pagesize); |
08fba699 | 826 | |
3340289d MG |
827 | /* |
828 | * Return the page size being used by the MMU to back a VMA. In the majority | |
829 | * of cases, the page size used by the kernel matches the MMU size. On | |
09135cc5 DW |
830 | * architectures where it differs, an architecture-specific 'strong' |
831 | * version of this symbol is required. | |
3340289d | 832 | */ |
09135cc5 | 833 | __weak unsigned long vma_mmu_pagesize(struct vm_area_struct *vma) |
3340289d MG |
834 | { |
835 | return vma_kernel_pagesize(vma); | |
836 | } | |
3340289d | 837 | |
84afd99b AW |
838 | /* |
839 | * Flags for MAP_PRIVATE reservations. These are stored in the bottom | |
840 | * bits of the reservation map pointer, which are always clear due to | |
841 | * alignment. | |
842 | */ | |
843 | #define HPAGE_RESV_OWNER (1UL << 0) | |
844 | #define HPAGE_RESV_UNMAPPED (1UL << 1) | |
04f2cbe3 | 845 | #define HPAGE_RESV_MASK (HPAGE_RESV_OWNER | HPAGE_RESV_UNMAPPED) |
84afd99b | 846 | |
a1e78772 MG |
847 | /* |
848 | * These helpers are used to track how many pages are reserved for | |
849 | * faults in a MAP_PRIVATE mapping. Only the process that called mmap() | |
850 | * is guaranteed to have their future faults succeed. | |
851 | * | |
852 | * With the exception of reset_vma_resv_huge_pages() which is called at fork(), | |
853 | * the reserve counters are updated with the hugetlb_lock held. It is safe | |
854 | * to reset the VMA at fork() time as it is not in use yet and there is no | |
855 | * chance of the global counters getting corrupted as a result of the values. | |
84afd99b AW |
856 | * |
857 | * The private mapping reservation is represented in a subtly different | |
858 | * manner to a shared mapping. A shared mapping has a region map associated | |
859 | * with the underlying file, this region map represents the backing file | |
860 | * pages which have ever had a reservation assigned which this persists even | |
861 | * after the page is instantiated. A private mapping has a region map | |
862 | * associated with the original mmap which is attached to all VMAs which | |
863 | * reference it, this region map represents those offsets which have consumed | |
864 | * reservation ie. where pages have been instantiated. | |
a1e78772 | 865 | */ |
e7c4b0bf AW |
866 | static unsigned long get_vma_private_data(struct vm_area_struct *vma) |
867 | { | |
868 | return (unsigned long)vma->vm_private_data; | |
869 | } | |
870 | ||
871 | static void set_vma_private_data(struct vm_area_struct *vma, | |
872 | unsigned long value) | |
873 | { | |
874 | vma->vm_private_data = (void *)value; | |
875 | } | |
876 | ||
e9fe92ae MA |
877 | static void |
878 | resv_map_set_hugetlb_cgroup_uncharge_info(struct resv_map *resv_map, | |
879 | struct hugetlb_cgroup *h_cg, | |
880 | struct hstate *h) | |
881 | { | |
882 | #ifdef CONFIG_CGROUP_HUGETLB | |
883 | if (!h_cg || !h) { | |
884 | resv_map->reservation_counter = NULL; | |
885 | resv_map->pages_per_hpage = 0; | |
886 | resv_map->css = NULL; | |
887 | } else { | |
888 | resv_map->reservation_counter = | |
889 | &h_cg->rsvd_hugepage[hstate_index(h)]; | |
890 | resv_map->pages_per_hpage = pages_per_huge_page(h); | |
891 | resv_map->css = &h_cg->css; | |
892 | } | |
893 | #endif | |
894 | } | |
895 | ||
9119a41e | 896 | struct resv_map *resv_map_alloc(void) |
84afd99b AW |
897 | { |
898 | struct resv_map *resv_map = kmalloc(sizeof(*resv_map), GFP_KERNEL); | |
5e911373 MK |
899 | struct file_region *rg = kmalloc(sizeof(*rg), GFP_KERNEL); |
900 | ||
901 | if (!resv_map || !rg) { | |
902 | kfree(resv_map); | |
903 | kfree(rg); | |
84afd99b | 904 | return NULL; |
5e911373 | 905 | } |
84afd99b AW |
906 | |
907 | kref_init(&resv_map->refs); | |
7b24d861 | 908 | spin_lock_init(&resv_map->lock); |
84afd99b AW |
909 | INIT_LIST_HEAD(&resv_map->regions); |
910 | ||
5e911373 | 911 | resv_map->adds_in_progress = 0; |
e9fe92ae MA |
912 | /* |
913 | * Initialize these to 0. On shared mappings, 0's here indicate these | |
914 | * fields don't do cgroup accounting. On private mappings, these will be | |
915 | * re-initialized to the proper values, to indicate that hugetlb cgroup | |
916 | * reservations are to be un-charged from here. | |
917 | */ | |
918 | resv_map_set_hugetlb_cgroup_uncharge_info(resv_map, NULL, NULL); | |
5e911373 MK |
919 | |
920 | INIT_LIST_HEAD(&resv_map->region_cache); | |
921 | list_add(&rg->link, &resv_map->region_cache); | |
922 | resv_map->region_cache_count = 1; | |
923 | ||
84afd99b AW |
924 | return resv_map; |
925 | } | |
926 | ||
9119a41e | 927 | void resv_map_release(struct kref *ref) |
84afd99b AW |
928 | { |
929 | struct resv_map *resv_map = container_of(ref, struct resv_map, refs); | |
5e911373 MK |
930 | struct list_head *head = &resv_map->region_cache; |
931 | struct file_region *rg, *trg; | |
84afd99b AW |
932 | |
933 | /* Clear out any active regions before we release the map. */ | |
feba16e2 | 934 | region_del(resv_map, 0, LONG_MAX); |
5e911373 MK |
935 | |
936 | /* ... and any entries left in the cache */ | |
937 | list_for_each_entry_safe(rg, trg, head, link) { | |
938 | list_del(&rg->link); | |
939 | kfree(rg); | |
940 | } | |
941 | ||
942 | VM_BUG_ON(resv_map->adds_in_progress); | |
943 | ||
84afd99b AW |
944 | kfree(resv_map); |
945 | } | |
946 | ||
4e35f483 JK |
947 | static inline struct resv_map *inode_resv_map(struct inode *inode) |
948 | { | |
f27a5136 MK |
949 | /* |
950 | * At inode evict time, i_mapping may not point to the original | |
951 | * address space within the inode. This original address space | |
952 | * contains the pointer to the resv_map. So, always use the | |
953 | * address space embedded within the inode. | |
954 | * The VERY common case is inode->mapping == &inode->i_data but, | |
955 | * this may not be true for device special inodes. | |
956 | */ | |
957 | return (struct resv_map *)(&inode->i_data)->private_data; | |
4e35f483 JK |
958 | } |
959 | ||
84afd99b | 960 | static struct resv_map *vma_resv_map(struct vm_area_struct *vma) |
a1e78772 | 961 | { |
81d1b09c | 962 | VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); |
4e35f483 JK |
963 | if (vma->vm_flags & VM_MAYSHARE) { |
964 | struct address_space *mapping = vma->vm_file->f_mapping; | |
965 | struct inode *inode = mapping->host; | |
966 | ||
967 | return inode_resv_map(inode); | |
968 | ||
969 | } else { | |
84afd99b AW |
970 | return (struct resv_map *)(get_vma_private_data(vma) & |
971 | ~HPAGE_RESV_MASK); | |
4e35f483 | 972 | } |
a1e78772 MG |
973 | } |
974 | ||
84afd99b | 975 | static void set_vma_resv_map(struct vm_area_struct *vma, struct resv_map *map) |
a1e78772 | 976 | { |
81d1b09c SL |
977 | VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); |
978 | VM_BUG_ON_VMA(vma->vm_flags & VM_MAYSHARE, vma); | |
a1e78772 | 979 | |
84afd99b AW |
980 | set_vma_private_data(vma, (get_vma_private_data(vma) & |
981 | HPAGE_RESV_MASK) | (unsigned long)map); | |
04f2cbe3 MG |
982 | } |
983 | ||
984 | static void set_vma_resv_flags(struct vm_area_struct *vma, unsigned long flags) | |
985 | { | |
81d1b09c SL |
986 | VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); |
987 | VM_BUG_ON_VMA(vma->vm_flags & VM_MAYSHARE, vma); | |
e7c4b0bf AW |
988 | |
989 | set_vma_private_data(vma, get_vma_private_data(vma) | flags); | |
04f2cbe3 MG |
990 | } |
991 | ||
992 | static int is_vma_resv_set(struct vm_area_struct *vma, unsigned long flag) | |
993 | { | |
81d1b09c | 994 | VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); |
e7c4b0bf AW |
995 | |
996 | return (get_vma_private_data(vma) & flag) != 0; | |
a1e78772 MG |
997 | } |
998 | ||
04f2cbe3 | 999 | /* Reset counters to 0 and clear all HPAGE_RESV_* flags */ |
a1e78772 MG |
1000 | void reset_vma_resv_huge_pages(struct vm_area_struct *vma) |
1001 | { | |
81d1b09c | 1002 | VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); |
f83a275d | 1003 | if (!(vma->vm_flags & VM_MAYSHARE)) |
a1e78772 MG |
1004 | vma->vm_private_data = (void *)0; |
1005 | } | |
1006 | ||
1007 | /* Returns true if the VMA has associated reserve pages */ | |
559ec2f8 | 1008 | static bool vma_has_reserves(struct vm_area_struct *vma, long chg) |
a1e78772 | 1009 | { |
af0ed73e JK |
1010 | if (vma->vm_flags & VM_NORESERVE) { |
1011 | /* | |
1012 | * This address is already reserved by other process(chg == 0), | |
1013 | * so, we should decrement reserved count. Without decrementing, | |
1014 | * reserve count remains after releasing inode, because this | |
1015 | * allocated page will go into page cache and is regarded as | |
1016 | * coming from reserved pool in releasing step. Currently, we | |
1017 | * don't have any other solution to deal with this situation | |
1018 | * properly, so add work-around here. | |
1019 | */ | |
1020 | if (vma->vm_flags & VM_MAYSHARE && chg == 0) | |
559ec2f8 | 1021 | return true; |
af0ed73e | 1022 | else |
559ec2f8 | 1023 | return false; |
af0ed73e | 1024 | } |
a63884e9 JK |
1025 | |
1026 | /* Shared mappings always use reserves */ | |
1fb1b0e9 MK |
1027 | if (vma->vm_flags & VM_MAYSHARE) { |
1028 | /* | |
1029 | * We know VM_NORESERVE is not set. Therefore, there SHOULD | |
1030 | * be a region map for all pages. The only situation where | |
1031 | * there is no region map is if a hole was punched via | |
7c8de358 | 1032 | * fallocate. In this case, there really are no reserves to |
1fb1b0e9 MK |
1033 | * use. This situation is indicated if chg != 0. |
1034 | */ | |
1035 | if (chg) | |
1036 | return false; | |
1037 | else | |
1038 | return true; | |
1039 | } | |
a63884e9 JK |
1040 | |
1041 | /* | |
1042 | * Only the process that called mmap() has reserves for | |
1043 | * private mappings. | |
1044 | */ | |
67961f9d MK |
1045 | if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { |
1046 | /* | |
1047 | * Like the shared case above, a hole punch or truncate | |
1048 | * could have been performed on the private mapping. | |
1049 | * Examine the value of chg to determine if reserves | |
1050 | * actually exist or were previously consumed. | |
1051 | * Very Subtle - The value of chg comes from a previous | |
1052 | * call to vma_needs_reserves(). The reserve map for | |
1053 | * private mappings has different (opposite) semantics | |
1054 | * than that of shared mappings. vma_needs_reserves() | |
1055 | * has already taken this difference in semantics into | |
1056 | * account. Therefore, the meaning of chg is the same | |
1057 | * as in the shared case above. Code could easily be | |
1058 | * combined, but keeping it separate draws attention to | |
1059 | * subtle differences. | |
1060 | */ | |
1061 | if (chg) | |
1062 | return false; | |
1063 | else | |
1064 | return true; | |
1065 | } | |
a63884e9 | 1066 | |
559ec2f8 | 1067 | return false; |
a1e78772 MG |
1068 | } |
1069 | ||
a5516438 | 1070 | static void enqueue_huge_page(struct hstate *h, struct page *page) |
1da177e4 LT |
1071 | { |
1072 | int nid = page_to_nid(page); | |
9487ca60 MK |
1073 | |
1074 | lockdep_assert_held(&hugetlb_lock); | |
0edaecfa | 1075 | list_move(&page->lru, &h->hugepage_freelists[nid]); |
a5516438 AK |
1076 | h->free_huge_pages++; |
1077 | h->free_huge_pages_node[nid]++; | |
6c037149 | 1078 | SetHPageFreed(page); |
1da177e4 LT |
1079 | } |
1080 | ||
94310cbc | 1081 | static struct page *dequeue_huge_page_node_exact(struct hstate *h, int nid) |
bf50bab2 NH |
1082 | { |
1083 | struct page *page; | |
1a08ae36 | 1084 | bool pin = !!(current->flags & PF_MEMALLOC_PIN); |
bbe88753 | 1085 | |
9487ca60 | 1086 | lockdep_assert_held(&hugetlb_lock); |
bbe88753 | 1087 | list_for_each_entry(page, &h->hugepage_freelists[nid], lru) { |
8e3560d9 | 1088 | if (pin && !is_pinnable_page(page)) |
bbe88753 | 1089 | continue; |
bf50bab2 | 1090 | |
6664bfc8 WY |
1091 | if (PageHWPoison(page)) |
1092 | continue; | |
1093 | ||
1094 | list_move(&page->lru, &h->hugepage_activelist); | |
1095 | set_page_refcounted(page); | |
6c037149 | 1096 | ClearHPageFreed(page); |
6664bfc8 WY |
1097 | h->free_huge_pages--; |
1098 | h->free_huge_pages_node[nid]--; | |
1099 | return page; | |
bbe88753 JK |
1100 | } |
1101 | ||
6664bfc8 | 1102 | return NULL; |
bf50bab2 NH |
1103 | } |
1104 | ||
3e59fcb0 MH |
1105 | static struct page *dequeue_huge_page_nodemask(struct hstate *h, gfp_t gfp_mask, int nid, |
1106 | nodemask_t *nmask) | |
94310cbc | 1107 | { |
3e59fcb0 MH |
1108 | unsigned int cpuset_mems_cookie; |
1109 | struct zonelist *zonelist; | |
1110 | struct zone *zone; | |
1111 | struct zoneref *z; | |
98fa15f3 | 1112 | int node = NUMA_NO_NODE; |
94310cbc | 1113 | |
3e59fcb0 MH |
1114 | zonelist = node_zonelist(nid, gfp_mask); |
1115 | ||
1116 | retry_cpuset: | |
1117 | cpuset_mems_cookie = read_mems_allowed_begin(); | |
1118 | for_each_zone_zonelist_nodemask(zone, z, zonelist, gfp_zone(gfp_mask), nmask) { | |
1119 | struct page *page; | |
1120 | ||
1121 | if (!cpuset_zone_allowed(zone, gfp_mask)) | |
1122 | continue; | |
1123 | /* | |
1124 | * no need to ask again on the same node. Pool is node rather than | |
1125 | * zone aware | |
1126 | */ | |
1127 | if (zone_to_nid(zone) == node) | |
1128 | continue; | |
1129 | node = zone_to_nid(zone); | |
94310cbc | 1130 | |
94310cbc AK |
1131 | page = dequeue_huge_page_node_exact(h, node); |
1132 | if (page) | |
1133 | return page; | |
1134 | } | |
3e59fcb0 MH |
1135 | if (unlikely(read_mems_allowed_retry(cpuset_mems_cookie))) |
1136 | goto retry_cpuset; | |
1137 | ||
94310cbc AK |
1138 | return NULL; |
1139 | } | |
1140 | ||
a5516438 AK |
1141 | static struct page *dequeue_huge_page_vma(struct hstate *h, |
1142 | struct vm_area_struct *vma, | |
af0ed73e JK |
1143 | unsigned long address, int avoid_reserve, |
1144 | long chg) | |
1da177e4 | 1145 | { |
3e59fcb0 | 1146 | struct page *page; |
480eccf9 | 1147 | struct mempolicy *mpol; |
04ec6264 | 1148 | gfp_t gfp_mask; |
3e59fcb0 | 1149 | nodemask_t *nodemask; |
04ec6264 | 1150 | int nid; |
1da177e4 | 1151 | |
a1e78772 MG |
1152 | /* |
1153 | * A child process with MAP_PRIVATE mappings created by their parent | |
1154 | * have no page reserves. This check ensures that reservations are | |
1155 | * not "stolen". The child may still get SIGKILLed | |
1156 | */ | |
af0ed73e | 1157 | if (!vma_has_reserves(vma, chg) && |
a5516438 | 1158 | h->free_huge_pages - h->resv_huge_pages == 0) |
c0ff7453 | 1159 | goto err; |
a1e78772 | 1160 | |
04f2cbe3 | 1161 | /* If reserves cannot be used, ensure enough pages are in the pool */ |
a5516438 | 1162 | if (avoid_reserve && h->free_huge_pages - h->resv_huge_pages == 0) |
6eab04a8 | 1163 | goto err; |
04f2cbe3 | 1164 | |
04ec6264 VB |
1165 | gfp_mask = htlb_alloc_mask(h); |
1166 | nid = huge_node(vma, address, gfp_mask, &mpol, &nodemask); | |
3e59fcb0 MH |
1167 | page = dequeue_huge_page_nodemask(h, gfp_mask, nid, nodemask); |
1168 | if (page && !avoid_reserve && vma_has_reserves(vma, chg)) { | |
d6995da3 | 1169 | SetHPageRestoreReserve(page); |
3e59fcb0 | 1170 | h->resv_huge_pages--; |
1da177e4 | 1171 | } |
cc9a6c87 | 1172 | |
52cd3b07 | 1173 | mpol_cond_put(mpol); |
1da177e4 | 1174 | return page; |
cc9a6c87 MG |
1175 | |
1176 | err: | |
cc9a6c87 | 1177 | return NULL; |
1da177e4 LT |
1178 | } |
1179 | ||
1cac6f2c LC |
1180 | /* |
1181 | * common helper functions for hstate_next_node_to_{alloc|free}. | |
1182 | * We may have allocated or freed a huge page based on a different | |
1183 | * nodes_allowed previously, so h->next_node_to_{alloc|free} might | |
1184 | * be outside of *nodes_allowed. Ensure that we use an allowed | |
1185 | * node for alloc or free. | |
1186 | */ | |
1187 | static int next_node_allowed(int nid, nodemask_t *nodes_allowed) | |
1188 | { | |
0edaf86c | 1189 | nid = next_node_in(nid, *nodes_allowed); |
1cac6f2c LC |
1190 | VM_BUG_ON(nid >= MAX_NUMNODES); |
1191 | ||
1192 | return nid; | |
1193 | } | |
1194 | ||
1195 | static int get_valid_node_allowed(int nid, nodemask_t *nodes_allowed) | |
1196 | { | |
1197 | if (!node_isset(nid, *nodes_allowed)) | |
1198 | nid = next_node_allowed(nid, nodes_allowed); | |
1199 | return nid; | |
1200 | } | |
1201 | ||
1202 | /* | |
1203 | * returns the previously saved node ["this node"] from which to | |
1204 | * allocate a persistent huge page for the pool and advance the | |
1205 | * next node from which to allocate, handling wrap at end of node | |
1206 | * mask. | |
1207 | */ | |
1208 | static int hstate_next_node_to_alloc(struct hstate *h, | |
1209 | nodemask_t *nodes_allowed) | |
1210 | { | |
1211 | int nid; | |
1212 | ||
1213 | VM_BUG_ON(!nodes_allowed); | |
1214 | ||
1215 | nid = get_valid_node_allowed(h->next_nid_to_alloc, nodes_allowed); | |
1216 | h->next_nid_to_alloc = next_node_allowed(nid, nodes_allowed); | |
1217 | ||
1218 | return nid; | |
1219 | } | |
1220 | ||
1221 | /* | |
10c6ec49 | 1222 | * helper for remove_pool_huge_page() - return the previously saved |
1cac6f2c LC |
1223 | * node ["this node"] from which to free a huge page. Advance the |
1224 | * next node id whether or not we find a free huge page to free so | |
1225 | * that the next attempt to free addresses the next node. | |
1226 | */ | |
1227 | static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed) | |
1228 | { | |
1229 | int nid; | |
1230 | ||
1231 | VM_BUG_ON(!nodes_allowed); | |
1232 | ||
1233 | nid = get_valid_node_allowed(h->next_nid_to_free, nodes_allowed); | |
1234 | h->next_nid_to_free = next_node_allowed(nid, nodes_allowed); | |
1235 | ||
1236 | return nid; | |
1237 | } | |
1238 | ||
1239 | #define for_each_node_mask_to_alloc(hs, nr_nodes, node, mask) \ | |
1240 | for (nr_nodes = nodes_weight(*mask); \ | |
1241 | nr_nodes > 0 && \ | |
1242 | ((node = hstate_next_node_to_alloc(hs, mask)) || 1); \ | |
1243 | nr_nodes--) | |
1244 | ||
1245 | #define for_each_node_mask_to_free(hs, nr_nodes, node, mask) \ | |
1246 | for (nr_nodes = nodes_weight(*mask); \ | |
1247 | nr_nodes > 0 && \ | |
1248 | ((node = hstate_next_node_to_free(hs, mask)) || 1); \ | |
1249 | nr_nodes--) | |
1250 | ||
e1073d1e | 1251 | #ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE |
944d9fec | 1252 | static void destroy_compound_gigantic_page(struct page *page, |
d00181b9 | 1253 | unsigned int order) |
944d9fec LC |
1254 | { |
1255 | int i; | |
1256 | int nr_pages = 1 << order; | |
1257 | struct page *p = page + 1; | |
1258 | ||
c8cc708a | 1259 | atomic_set(compound_mapcount_ptr(page), 0); |
5291c09b | 1260 | atomic_set(compound_pincount_ptr(page), 0); |
47e29d32 | 1261 | |
944d9fec | 1262 | for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) { |
1d798ca3 | 1263 | clear_compound_head(p); |
944d9fec | 1264 | set_page_refcounted(p); |
944d9fec LC |
1265 | } |
1266 | ||
1267 | set_compound_order(page, 0); | |
ba9c1201 | 1268 | page[1].compound_nr = 0; |
944d9fec LC |
1269 | __ClearPageHead(page); |
1270 | } | |
1271 | ||
d00181b9 | 1272 | static void free_gigantic_page(struct page *page, unsigned int order) |
944d9fec | 1273 | { |
cf11e85f RG |
1274 | /* |
1275 | * If the page isn't allocated using the cma allocator, | |
1276 | * cma_release() returns false. | |
1277 | */ | |
dbda8fea BS |
1278 | #ifdef CONFIG_CMA |
1279 | if (cma_release(hugetlb_cma[page_to_nid(page)], page, 1 << order)) | |
cf11e85f | 1280 | return; |
dbda8fea | 1281 | #endif |
cf11e85f | 1282 | |
944d9fec LC |
1283 | free_contig_range(page_to_pfn(page), 1 << order); |
1284 | } | |
1285 | ||
4eb0716e | 1286 | #ifdef CONFIG_CONTIG_ALLOC |
d9cc948f MH |
1287 | static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask, |
1288 | int nid, nodemask_t *nodemask) | |
944d9fec | 1289 | { |
04adbc3f | 1290 | unsigned long nr_pages = pages_per_huge_page(h); |
953f064a LX |
1291 | if (nid == NUMA_NO_NODE) |
1292 | nid = numa_mem_id(); | |
944d9fec | 1293 | |
dbda8fea BS |
1294 | #ifdef CONFIG_CMA |
1295 | { | |
cf11e85f RG |
1296 | struct page *page; |
1297 | int node; | |
1298 | ||
953f064a LX |
1299 | if (hugetlb_cma[nid]) { |
1300 | page = cma_alloc(hugetlb_cma[nid], nr_pages, | |
1301 | huge_page_order(h), true); | |
cf11e85f RG |
1302 | if (page) |
1303 | return page; | |
1304 | } | |
953f064a LX |
1305 | |
1306 | if (!(gfp_mask & __GFP_THISNODE)) { | |
1307 | for_each_node_mask(node, *nodemask) { | |
1308 | if (node == nid || !hugetlb_cma[node]) | |
1309 | continue; | |
1310 | ||
1311 | page = cma_alloc(hugetlb_cma[node], nr_pages, | |
1312 | huge_page_order(h), true); | |
1313 | if (page) | |
1314 | return page; | |
1315 | } | |
1316 | } | |
cf11e85f | 1317 | } |
dbda8fea | 1318 | #endif |
cf11e85f | 1319 | |
5e27a2df | 1320 | return alloc_contig_pages(nr_pages, gfp_mask, nid, nodemask); |
944d9fec LC |
1321 | } |
1322 | ||
4eb0716e AG |
1323 | #else /* !CONFIG_CONTIG_ALLOC */ |
1324 | static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask, | |
1325 | int nid, nodemask_t *nodemask) | |
1326 | { | |
1327 | return NULL; | |
1328 | } | |
1329 | #endif /* CONFIG_CONTIG_ALLOC */ | |
944d9fec | 1330 | |
e1073d1e | 1331 | #else /* !CONFIG_ARCH_HAS_GIGANTIC_PAGE */ |
d9cc948f | 1332 | static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask, |
4eb0716e AG |
1333 | int nid, nodemask_t *nodemask) |
1334 | { | |
1335 | return NULL; | |
1336 | } | |
d00181b9 | 1337 | static inline void free_gigantic_page(struct page *page, unsigned int order) { } |
944d9fec | 1338 | static inline void destroy_compound_gigantic_page(struct page *page, |
d00181b9 | 1339 | unsigned int order) { } |
944d9fec LC |
1340 | #endif |
1341 | ||
6eb4e88a MK |
1342 | /* |
1343 | * Remove hugetlb page from lists, and update dtor so that page appears | |
1344 | * as just a compound page. A reference is held on the page. | |
1345 | * | |
1346 | * Must be called with hugetlb lock held. | |
1347 | */ | |
1348 | static void remove_hugetlb_page(struct hstate *h, struct page *page, | |
1349 | bool adjust_surplus) | |
1350 | { | |
1351 | int nid = page_to_nid(page); | |
1352 | ||
1353 | VM_BUG_ON_PAGE(hugetlb_cgroup_from_page(page), page); | |
1354 | VM_BUG_ON_PAGE(hugetlb_cgroup_from_page_rsvd(page), page); | |
1355 | ||
9487ca60 | 1356 | lockdep_assert_held(&hugetlb_lock); |
6eb4e88a MK |
1357 | if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) |
1358 | return; | |
1359 | ||
1360 | list_del(&page->lru); | |
1361 | ||
1362 | if (HPageFreed(page)) { | |
1363 | h->free_huge_pages--; | |
1364 | h->free_huge_pages_node[nid]--; | |
1365 | } | |
1366 | if (adjust_surplus) { | |
1367 | h->surplus_huge_pages--; | |
1368 | h->surplus_huge_pages_node[nid]--; | |
1369 | } | |
1370 | ||
1371 | set_page_refcounted(page); | |
1372 | set_compound_page_dtor(page, NULL_COMPOUND_DTOR); | |
1373 | ||
1374 | h->nr_huge_pages--; | |
1375 | h->nr_huge_pages_node[nid]--; | |
1376 | } | |
1377 | ||
ad2fa371 MS |
1378 | static void add_hugetlb_page(struct hstate *h, struct page *page, |
1379 | bool adjust_surplus) | |
1380 | { | |
1381 | int zeroed; | |
1382 | int nid = page_to_nid(page); | |
1383 | ||
1384 | VM_BUG_ON_PAGE(!HPageVmemmapOptimized(page), page); | |
1385 | ||
1386 | lockdep_assert_held(&hugetlb_lock); | |
1387 | ||
1388 | INIT_LIST_HEAD(&page->lru); | |
1389 | h->nr_huge_pages++; | |
1390 | h->nr_huge_pages_node[nid]++; | |
1391 | ||
1392 | if (adjust_surplus) { | |
1393 | h->surplus_huge_pages++; | |
1394 | h->surplus_huge_pages_node[nid]++; | |
1395 | } | |
1396 | ||
1397 | set_compound_page_dtor(page, HUGETLB_PAGE_DTOR); | |
1398 | set_page_private(page, 0); | |
1399 | SetHPageVmemmapOptimized(page); | |
1400 | ||
1401 | /* | |
1402 | * This page is now managed by the hugetlb allocator and has | |
1403 | * no users -- drop the last reference. | |
1404 | */ | |
1405 | zeroed = put_page_testzero(page); | |
1406 | VM_BUG_ON_PAGE(!zeroed, page); | |
1407 | arch_clear_hugepage_flags(page); | |
1408 | enqueue_huge_page(h, page); | |
1409 | } | |
1410 | ||
b65d4adb | 1411 | static void __update_and_free_page(struct hstate *h, struct page *page) |
6af2acb6 AL |
1412 | { |
1413 | int i; | |
dbfee5ae | 1414 | struct page *subpage = page; |
a5516438 | 1415 | |
4eb0716e | 1416 | if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) |
944d9fec | 1417 | return; |
18229df5 | 1418 | |
ad2fa371 MS |
1419 | if (alloc_huge_page_vmemmap(h, page)) { |
1420 | spin_lock_irq(&hugetlb_lock); | |
1421 | /* | |
1422 | * If we cannot allocate vmemmap pages, just refuse to free the | |
1423 | * page and put the page back on the hugetlb free list and treat | |
1424 | * as a surplus page. | |
1425 | */ | |
1426 | add_hugetlb_page(h, page, true); | |
1427 | spin_unlock_irq(&hugetlb_lock); | |
1428 | return; | |
1429 | } | |
1430 | ||
dbfee5ae MK |
1431 | for (i = 0; i < pages_per_huge_page(h); |
1432 | i++, subpage = mem_map_next(subpage, page, i)) { | |
1433 | subpage->flags &= ~(1 << PG_locked | 1 << PG_error | | |
32f84528 | 1434 | 1 << PG_referenced | 1 << PG_dirty | |
a7407a27 LC |
1435 | 1 << PG_active | 1 << PG_private | |
1436 | 1 << PG_writeback); | |
6af2acb6 | 1437 | } |
944d9fec LC |
1438 | if (hstate_is_gigantic(h)) { |
1439 | destroy_compound_gigantic_page(page, huge_page_order(h)); | |
1440 | free_gigantic_page(page, huge_page_order(h)); | |
1441 | } else { | |
944d9fec LC |
1442 | __free_pages(page, huge_page_order(h)); |
1443 | } | |
6af2acb6 AL |
1444 | } |
1445 | ||
b65d4adb MS |
1446 | /* |
1447 | * As update_and_free_page() can be called under any context, so we cannot | |
1448 | * use GFP_KERNEL to allocate vmemmap pages. However, we can defer the | |
1449 | * actual freeing in a workqueue to prevent from using GFP_ATOMIC to allocate | |
1450 | * the vmemmap pages. | |
1451 | * | |
1452 | * free_hpage_workfn() locklessly retrieves the linked list of pages to be | |
1453 | * freed and frees them one-by-one. As the page->mapping pointer is going | |
1454 | * to be cleared in free_hpage_workfn() anyway, it is reused as the llist_node | |
1455 | * structure of a lockless linked list of huge pages to be freed. | |
1456 | */ | |
1457 | static LLIST_HEAD(hpage_freelist); | |
1458 | ||
1459 | static void free_hpage_workfn(struct work_struct *work) | |
1460 | { | |
1461 | struct llist_node *node; | |
1462 | ||
1463 | node = llist_del_all(&hpage_freelist); | |
1464 | ||
1465 | while (node) { | |
1466 | struct page *page; | |
1467 | struct hstate *h; | |
1468 | ||
1469 | page = container_of((struct address_space **)node, | |
1470 | struct page, mapping); | |
1471 | node = node->next; | |
1472 | page->mapping = NULL; | |
1473 | /* | |
1474 | * The VM_BUG_ON_PAGE(!PageHuge(page), page) in page_hstate() | |
1475 | * is going to trigger because a previous call to | |
1476 | * remove_hugetlb_page() will set_compound_page_dtor(page, | |
1477 | * NULL_COMPOUND_DTOR), so do not use page_hstate() directly. | |
1478 | */ | |
1479 | h = size_to_hstate(page_size(page)); | |
1480 | ||
1481 | __update_and_free_page(h, page); | |
1482 | ||
1483 | cond_resched(); | |
1484 | } | |
1485 | } | |
1486 | static DECLARE_WORK(free_hpage_work, free_hpage_workfn); | |
1487 | ||
1488 | static inline void flush_free_hpage_work(struct hstate *h) | |
1489 | { | |
1490 | if (free_vmemmap_pages_per_hpage(h)) | |
1491 | flush_work(&free_hpage_work); | |
1492 | } | |
1493 | ||
1494 | static void update_and_free_page(struct hstate *h, struct page *page, | |
1495 | bool atomic) | |
1496 | { | |
ad2fa371 | 1497 | if (!HPageVmemmapOptimized(page) || !atomic) { |
b65d4adb MS |
1498 | __update_and_free_page(h, page); |
1499 | return; | |
1500 | } | |
1501 | ||
1502 | /* | |
1503 | * Defer freeing to avoid using GFP_ATOMIC to allocate vmemmap pages. | |
1504 | * | |
1505 | * Only call schedule_work() if hpage_freelist is previously | |
1506 | * empty. Otherwise, schedule_work() had been called but the workfn | |
1507 | * hasn't retrieved the list yet. | |
1508 | */ | |
1509 | if (llist_add((struct llist_node *)&page->mapping, &hpage_freelist)) | |
1510 | schedule_work(&free_hpage_work); | |
1511 | } | |
1512 | ||
10c6ec49 MK |
1513 | static void update_and_free_pages_bulk(struct hstate *h, struct list_head *list) |
1514 | { | |
1515 | struct page *page, *t_page; | |
1516 | ||
1517 | list_for_each_entry_safe(page, t_page, list, lru) { | |
b65d4adb | 1518 | update_and_free_page(h, page, false); |
10c6ec49 MK |
1519 | cond_resched(); |
1520 | } | |
1521 | } | |
1522 | ||
e5ff2159 AK |
1523 | struct hstate *size_to_hstate(unsigned long size) |
1524 | { | |
1525 | struct hstate *h; | |
1526 | ||
1527 | for_each_hstate(h) { | |
1528 | if (huge_page_size(h) == size) | |
1529 | return h; | |
1530 | } | |
1531 | return NULL; | |
1532 | } | |
1533 | ||
db71ef79 | 1534 | void free_huge_page(struct page *page) |
27a85ef1 | 1535 | { |
a5516438 AK |
1536 | /* |
1537 | * Can't pass hstate in here because it is called from the | |
1538 | * compound page destructor. | |
1539 | */ | |
e5ff2159 | 1540 | struct hstate *h = page_hstate(page); |
7893d1d5 | 1541 | int nid = page_to_nid(page); |
d6995da3 | 1542 | struct hugepage_subpool *spool = hugetlb_page_subpool(page); |
07443a85 | 1543 | bool restore_reserve; |
db71ef79 | 1544 | unsigned long flags; |
27a85ef1 | 1545 | |
b4330afb MK |
1546 | VM_BUG_ON_PAGE(page_count(page), page); |
1547 | VM_BUG_ON_PAGE(page_mapcount(page), page); | |
8ace22bc | 1548 | |
d6995da3 | 1549 | hugetlb_set_page_subpool(page, NULL); |
8ace22bc | 1550 | page->mapping = NULL; |
d6995da3 MK |
1551 | restore_reserve = HPageRestoreReserve(page); |
1552 | ClearHPageRestoreReserve(page); | |
27a85ef1 | 1553 | |
1c5ecae3 | 1554 | /* |
d6995da3 | 1555 | * If HPageRestoreReserve was set on page, page allocation consumed a |
0919e1b6 MK |
1556 | * reservation. If the page was associated with a subpool, there |
1557 | * would have been a page reserved in the subpool before allocation | |
1558 | * via hugepage_subpool_get_pages(). Since we are 'restoring' the | |
6c26d310 | 1559 | * reservation, do not call hugepage_subpool_put_pages() as this will |
0919e1b6 | 1560 | * remove the reserved page from the subpool. |
1c5ecae3 | 1561 | */ |
0919e1b6 MK |
1562 | if (!restore_reserve) { |
1563 | /* | |
1564 | * A return code of zero implies that the subpool will be | |
1565 | * under its minimum size if the reservation is not restored | |
1566 | * after page is free. Therefore, force restore_reserve | |
1567 | * operation. | |
1568 | */ | |
1569 | if (hugepage_subpool_put_pages(spool, 1) == 0) | |
1570 | restore_reserve = true; | |
1571 | } | |
1c5ecae3 | 1572 | |
db71ef79 | 1573 | spin_lock_irqsave(&hugetlb_lock, flags); |
8f251a3d | 1574 | ClearHPageMigratable(page); |
6d76dcf4 AK |
1575 | hugetlb_cgroup_uncharge_page(hstate_index(h), |
1576 | pages_per_huge_page(h), page); | |
08cf9faf MA |
1577 | hugetlb_cgroup_uncharge_page_rsvd(hstate_index(h), |
1578 | pages_per_huge_page(h), page); | |
07443a85 JK |
1579 | if (restore_reserve) |
1580 | h->resv_huge_pages++; | |
1581 | ||
9157c311 | 1582 | if (HPageTemporary(page)) { |
6eb4e88a | 1583 | remove_hugetlb_page(h, page, false); |
db71ef79 | 1584 | spin_unlock_irqrestore(&hugetlb_lock, flags); |
b65d4adb | 1585 | update_and_free_page(h, page, true); |
ab5ac90a | 1586 | } else if (h->surplus_huge_pages_node[nid]) { |
0edaecfa | 1587 | /* remove the page from active list */ |
6eb4e88a | 1588 | remove_hugetlb_page(h, page, true); |
db71ef79 | 1589 | spin_unlock_irqrestore(&hugetlb_lock, flags); |
b65d4adb | 1590 | update_and_free_page(h, page, true); |
7893d1d5 | 1591 | } else { |
5d3a551c | 1592 | arch_clear_hugepage_flags(page); |
a5516438 | 1593 | enqueue_huge_page(h, page); |
db71ef79 | 1594 | spin_unlock_irqrestore(&hugetlb_lock, flags); |
c77c0a8a | 1595 | } |
c77c0a8a WL |
1596 | } |
1597 | ||
d3d99fcc OS |
1598 | /* |
1599 | * Must be called with the hugetlb lock held | |
1600 | */ | |
1601 | static void __prep_account_new_huge_page(struct hstate *h, int nid) | |
1602 | { | |
1603 | lockdep_assert_held(&hugetlb_lock); | |
1604 | h->nr_huge_pages++; | |
1605 | h->nr_huge_pages_node[nid]++; | |
1606 | } | |
1607 | ||
f41f2ed4 | 1608 | static void __prep_new_huge_page(struct hstate *h, struct page *page) |
b7ba30c6 | 1609 | { |
f41f2ed4 | 1610 | free_huge_page_vmemmap(h, page); |
0edaecfa | 1611 | INIT_LIST_HEAD(&page->lru); |
f1e61557 | 1612 | set_compound_page_dtor(page, HUGETLB_PAGE_DTOR); |
ff546117 | 1613 | hugetlb_set_page_subpool(page, NULL); |
9dd540e2 | 1614 | set_hugetlb_cgroup(page, NULL); |
1adc4d41 | 1615 | set_hugetlb_cgroup_rsvd(page, NULL); |
d3d99fcc OS |
1616 | } |
1617 | ||
1618 | static void prep_new_huge_page(struct hstate *h, struct page *page, int nid) | |
1619 | { | |
f41f2ed4 | 1620 | __prep_new_huge_page(h, page); |
db71ef79 | 1621 | spin_lock_irq(&hugetlb_lock); |
d3d99fcc | 1622 | __prep_account_new_huge_page(h, nid); |
db71ef79 | 1623 | spin_unlock_irq(&hugetlb_lock); |
b7ba30c6 AK |
1624 | } |
1625 | ||
7118fc29 | 1626 | static bool prep_compound_gigantic_page(struct page *page, unsigned int order) |
20a0307c | 1627 | { |
7118fc29 | 1628 | int i, j; |
20a0307c WF |
1629 | int nr_pages = 1 << order; |
1630 | struct page *p = page + 1; | |
1631 | ||
1632 | /* we rely on prep_new_huge_page to set the destructor */ | |
1633 | set_compound_order(page, order); | |
ef5a22be | 1634 | __ClearPageReserved(page); |
de09d31d | 1635 | __SetPageHead(page); |
20a0307c | 1636 | for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) { |
ef5a22be AA |
1637 | /* |
1638 | * For gigantic hugepages allocated through bootmem at | |
1639 | * boot, it's safer to be consistent with the not-gigantic | |
1640 | * hugepages and clear the PG_reserved bit from all tail pages | |
7c8de358 | 1641 | * too. Otherwise drivers using get_user_pages() to access tail |
ef5a22be AA |
1642 | * pages may get the reference counting wrong if they see |
1643 | * PG_reserved set on a tail page (despite the head page not | |
1644 | * having PG_reserved set). Enforcing this consistency between | |
1645 | * head and tail pages allows drivers to optimize away a check | |
1646 | * on the head page when they need know if put_page() is needed | |
1647 | * after get_user_pages(). | |
1648 | */ | |
1649 | __ClearPageReserved(p); | |
7118fc29 MK |
1650 | /* |
1651 | * Subtle and very unlikely | |
1652 | * | |
1653 | * Gigantic 'page allocators' such as memblock or cma will | |
1654 | * return a set of pages with each page ref counted. We need | |
1655 | * to turn this set of pages into a compound page with tail | |
1656 | * page ref counts set to zero. Code such as speculative page | |
1657 | * cache adding could take a ref on a 'to be' tail page. | |
1658 | * We need to respect any increased ref count, and only set | |
1659 | * the ref count to zero if count is currently 1. If count | |
1660 | * is not 1, we call synchronize_rcu in the hope that a rcu | |
1661 | * grace period will cause ref count to drop and then retry. | |
1662 | * If count is still inflated on retry we return an error and | |
1663 | * must discard the pages. | |
1664 | */ | |
1665 | if (!page_ref_freeze(p, 1)) { | |
1666 | pr_info("HugeTLB unexpected inflated ref count on freshly allocated page\n"); | |
1667 | synchronize_rcu(); | |
1668 | if (!page_ref_freeze(p, 1)) | |
1669 | goto out_error; | |
1670 | } | |
58a84aa9 | 1671 | set_page_count(p, 0); |
1d798ca3 | 1672 | set_compound_head(p, page); |
20a0307c | 1673 | } |
b4330afb | 1674 | atomic_set(compound_mapcount_ptr(page), -1); |
5291c09b | 1675 | atomic_set(compound_pincount_ptr(page), 0); |
7118fc29 MK |
1676 | return true; |
1677 | ||
1678 | out_error: | |
1679 | /* undo tail page modifications made above */ | |
1680 | p = page + 1; | |
1681 | for (j = 1; j < i; j++, p = mem_map_next(p, page, j)) { | |
1682 | clear_compound_head(p); | |
1683 | set_page_refcounted(p); | |
1684 | } | |
1685 | /* need to clear PG_reserved on remaining tail pages */ | |
1686 | for (; j < nr_pages; j++, p = mem_map_next(p, page, j)) | |
1687 | __ClearPageReserved(p); | |
1688 | set_compound_order(page, 0); | |
1689 | page[1].compound_nr = 0; | |
1690 | __ClearPageHead(page); | |
1691 | return false; | |
20a0307c WF |
1692 | } |
1693 | ||
7795912c AM |
1694 | /* |
1695 | * PageHuge() only returns true for hugetlbfs pages, but not for normal or | |
1696 | * transparent huge pages. See the PageTransHuge() documentation for more | |
1697 | * details. | |
1698 | */ | |
20a0307c WF |
1699 | int PageHuge(struct page *page) |
1700 | { | |
20a0307c WF |
1701 | if (!PageCompound(page)) |
1702 | return 0; | |
1703 | ||
1704 | page = compound_head(page); | |
f1e61557 | 1705 | return page[1].compound_dtor == HUGETLB_PAGE_DTOR; |
20a0307c | 1706 | } |
43131e14 NH |
1707 | EXPORT_SYMBOL_GPL(PageHuge); |
1708 | ||
27c73ae7 AA |
1709 | /* |
1710 | * PageHeadHuge() only returns true for hugetlbfs head page, but not for | |
1711 | * normal or transparent huge pages. | |
1712 | */ | |
1713 | int PageHeadHuge(struct page *page_head) | |
1714 | { | |
27c73ae7 AA |
1715 | if (!PageHead(page_head)) |
1716 | return 0; | |
1717 | ||
d4af73e3 | 1718 | return page_head[1].compound_dtor == HUGETLB_PAGE_DTOR; |
27c73ae7 | 1719 | } |
27c73ae7 | 1720 | |
c0d0381a MK |
1721 | /* |
1722 | * Find and lock address space (mapping) in write mode. | |
1723 | * | |
336bf30e MK |
1724 | * Upon entry, the page is locked which means that page_mapping() is |
1725 | * stable. Due to locking order, we can only trylock_write. If we can | |
1726 | * not get the lock, simply return NULL to caller. | |
c0d0381a MK |
1727 | */ |
1728 | struct address_space *hugetlb_page_mapping_lock_write(struct page *hpage) | |
1729 | { | |
336bf30e | 1730 | struct address_space *mapping = page_mapping(hpage); |
c0d0381a | 1731 | |
c0d0381a MK |
1732 | if (!mapping) |
1733 | return mapping; | |
1734 | ||
c0d0381a MK |
1735 | if (i_mmap_trylock_write(mapping)) |
1736 | return mapping; | |
1737 | ||
336bf30e | 1738 | return NULL; |
c0d0381a MK |
1739 | } |
1740 | ||
fe19bd3d | 1741 | pgoff_t hugetlb_basepage_index(struct page *page) |
13d60f4b ZY |
1742 | { |
1743 | struct page *page_head = compound_head(page); | |
1744 | pgoff_t index = page_index(page_head); | |
1745 | unsigned long compound_idx; | |
1746 | ||
13d60f4b ZY |
1747 | if (compound_order(page_head) >= MAX_ORDER) |
1748 | compound_idx = page_to_pfn(page) - page_to_pfn(page_head); | |
1749 | else | |
1750 | compound_idx = page - page_head; | |
1751 | ||
1752 | return (index << compound_order(page_head)) + compound_idx; | |
1753 | } | |
1754 | ||
0c397dae | 1755 | static struct page *alloc_buddy_huge_page(struct hstate *h, |
f60858f9 MK |
1756 | gfp_t gfp_mask, int nid, nodemask_t *nmask, |
1757 | nodemask_t *node_alloc_noretry) | |
1da177e4 | 1758 | { |
af0fb9df | 1759 | int order = huge_page_order(h); |
1da177e4 | 1760 | struct page *page; |
f60858f9 | 1761 | bool alloc_try_hard = true; |
f96efd58 | 1762 | |
f60858f9 MK |
1763 | /* |
1764 | * By default we always try hard to allocate the page with | |
1765 | * __GFP_RETRY_MAYFAIL flag. However, if we are allocating pages in | |
1766 | * a loop (to adjust global huge page counts) and previous allocation | |
1767 | * failed, do not continue to try hard on the same node. Use the | |
1768 | * node_alloc_noretry bitmap to manage this state information. | |
1769 | */ | |
1770 | if (node_alloc_noretry && node_isset(nid, *node_alloc_noretry)) | |
1771 | alloc_try_hard = false; | |
1772 | gfp_mask |= __GFP_COMP|__GFP_NOWARN; | |
1773 | if (alloc_try_hard) | |
1774 | gfp_mask |= __GFP_RETRY_MAYFAIL; | |
af0fb9df MH |
1775 | if (nid == NUMA_NO_NODE) |
1776 | nid = numa_mem_id(); | |
84172f4b | 1777 | page = __alloc_pages(gfp_mask, order, nid, nmask); |
af0fb9df MH |
1778 | if (page) |
1779 | __count_vm_event(HTLB_BUDDY_PGALLOC); | |
1780 | else | |
1781 | __count_vm_event(HTLB_BUDDY_PGALLOC_FAIL); | |
63b4613c | 1782 | |
f60858f9 MK |
1783 | /* |
1784 | * If we did not specify __GFP_RETRY_MAYFAIL, but still got a page this | |
1785 | * indicates an overall state change. Clear bit so that we resume | |
1786 | * normal 'try hard' allocations. | |
1787 | */ | |
1788 | if (node_alloc_noretry && page && !alloc_try_hard) | |
1789 | node_clear(nid, *node_alloc_noretry); | |
1790 | ||
1791 | /* | |
1792 | * If we tried hard to get a page but failed, set bit so that | |
1793 | * subsequent attempts will not try as hard until there is an | |
1794 | * overall state change. | |
1795 | */ | |
1796 | if (node_alloc_noretry && !page && alloc_try_hard) | |
1797 | node_set(nid, *node_alloc_noretry); | |
1798 | ||
63b4613c NA |
1799 | return page; |
1800 | } | |
1801 | ||
0c397dae MH |
1802 | /* |
1803 | * Common helper to allocate a fresh hugetlb page. All specific allocators | |
1804 | * should use this function to get new hugetlb pages | |
1805 | */ | |
1806 | static struct page *alloc_fresh_huge_page(struct hstate *h, | |
f60858f9 MK |
1807 | gfp_t gfp_mask, int nid, nodemask_t *nmask, |
1808 | nodemask_t *node_alloc_noretry) | |
0c397dae MH |
1809 | { |
1810 | struct page *page; | |
7118fc29 | 1811 | bool retry = false; |
0c397dae | 1812 | |
7118fc29 | 1813 | retry: |
0c397dae MH |
1814 | if (hstate_is_gigantic(h)) |
1815 | page = alloc_gigantic_page(h, gfp_mask, nid, nmask); | |
1816 | else | |
1817 | page = alloc_buddy_huge_page(h, gfp_mask, | |
f60858f9 | 1818 | nid, nmask, node_alloc_noretry); |
0c397dae MH |
1819 | if (!page) |
1820 | return NULL; | |
1821 | ||
7118fc29 MK |
1822 | if (hstate_is_gigantic(h)) { |
1823 | if (!prep_compound_gigantic_page(page, huge_page_order(h))) { | |
1824 | /* | |
1825 | * Rare failure to convert pages to compound page. | |
1826 | * Free pages and try again - ONCE! | |
1827 | */ | |
1828 | free_gigantic_page(page, huge_page_order(h)); | |
1829 | if (!retry) { | |
1830 | retry = true; | |
1831 | goto retry; | |
1832 | } | |
1833 | pr_warn("HugeTLB page can not be used due to unexpected inflated ref count\n"); | |
1834 | return NULL; | |
1835 | } | |
1836 | } | |
0c397dae MH |
1837 | prep_new_huge_page(h, page, page_to_nid(page)); |
1838 | ||
1839 | return page; | |
1840 | } | |
1841 | ||
af0fb9df MH |
1842 | /* |
1843 | * Allocates a fresh page to the hugetlb allocator pool in the node interleaved | |
1844 | * manner. | |
1845 | */ | |
f60858f9 MK |
1846 | static int alloc_pool_huge_page(struct hstate *h, nodemask_t *nodes_allowed, |
1847 | nodemask_t *node_alloc_noretry) | |
b2261026 JK |
1848 | { |
1849 | struct page *page; | |
1850 | int nr_nodes, node; | |
af0fb9df | 1851 | gfp_t gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE; |
b2261026 JK |
1852 | |
1853 | for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) { | |
f60858f9 MK |
1854 | page = alloc_fresh_huge_page(h, gfp_mask, node, nodes_allowed, |
1855 | node_alloc_noretry); | |
af0fb9df | 1856 | if (page) |
b2261026 | 1857 | break; |
b2261026 JK |
1858 | } |
1859 | ||
af0fb9df MH |
1860 | if (!page) |
1861 | return 0; | |
b2261026 | 1862 | |
af0fb9df MH |
1863 | put_page(page); /* free it into the hugepage allocator */ |
1864 | ||
1865 | return 1; | |
b2261026 JK |
1866 | } |
1867 | ||
e8c5c824 | 1868 | /* |
10c6ec49 MK |
1869 | * Remove huge page from pool from next node to free. Attempt to keep |
1870 | * persistent huge pages more or less balanced over allowed nodes. | |
1871 | * This routine only 'removes' the hugetlb page. The caller must make | |
1872 | * an additional call to free the page to low level allocators. | |
e8c5c824 LS |
1873 | * Called with hugetlb_lock locked. |
1874 | */ | |
10c6ec49 MK |
1875 | static struct page *remove_pool_huge_page(struct hstate *h, |
1876 | nodemask_t *nodes_allowed, | |
1877 | bool acct_surplus) | |
e8c5c824 | 1878 | { |
b2261026 | 1879 | int nr_nodes, node; |
10c6ec49 | 1880 | struct page *page = NULL; |
e8c5c824 | 1881 | |
9487ca60 | 1882 | lockdep_assert_held(&hugetlb_lock); |
b2261026 | 1883 | for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { |
685f3457 LS |
1884 | /* |
1885 | * If we're returning unused surplus pages, only examine | |
1886 | * nodes with surplus pages. | |
1887 | */ | |
b2261026 JK |
1888 | if ((!acct_surplus || h->surplus_huge_pages_node[node]) && |
1889 | !list_empty(&h->hugepage_freelists[node])) { | |
10c6ec49 | 1890 | page = list_entry(h->hugepage_freelists[node].next, |
e8c5c824 | 1891 | struct page, lru); |
6eb4e88a | 1892 | remove_hugetlb_page(h, page, acct_surplus); |
9a76db09 | 1893 | break; |
e8c5c824 | 1894 | } |
b2261026 | 1895 | } |
e8c5c824 | 1896 | |
10c6ec49 | 1897 | return page; |
e8c5c824 LS |
1898 | } |
1899 | ||
c8721bbb NH |
1900 | /* |
1901 | * Dissolve a given free hugepage into free buddy pages. This function does | |
faf53def NH |
1902 | * nothing for in-use hugepages and non-hugepages. |
1903 | * This function returns values like below: | |
1904 | * | |
ad2fa371 MS |
1905 | * -ENOMEM: failed to allocate vmemmap pages to free the freed hugepages |
1906 | * when the system is under memory pressure and the feature of | |
1907 | * freeing unused vmemmap pages associated with each hugetlb page | |
1908 | * is enabled. | |
1909 | * -EBUSY: failed to dissolved free hugepages or the hugepage is in-use | |
1910 | * (allocated or reserved.) | |
1911 | * 0: successfully dissolved free hugepages or the page is not a | |
1912 | * hugepage (considered as already dissolved) | |
c8721bbb | 1913 | */ |
c3114a84 | 1914 | int dissolve_free_huge_page(struct page *page) |
c8721bbb | 1915 | { |
6bc9b564 | 1916 | int rc = -EBUSY; |
082d5b6b | 1917 | |
7ffddd49 | 1918 | retry: |
faf53def NH |
1919 | /* Not to disrupt normal path by vainly holding hugetlb_lock */ |
1920 | if (!PageHuge(page)) | |
1921 | return 0; | |
1922 | ||
db71ef79 | 1923 | spin_lock_irq(&hugetlb_lock); |
faf53def NH |
1924 | if (!PageHuge(page)) { |
1925 | rc = 0; | |
1926 | goto out; | |
1927 | } | |
1928 | ||
1929 | if (!page_count(page)) { | |
2247bb33 GS |
1930 | struct page *head = compound_head(page); |
1931 | struct hstate *h = page_hstate(head); | |
6bc9b564 | 1932 | if (h->free_huge_pages - h->resv_huge_pages == 0) |
082d5b6b | 1933 | goto out; |
7ffddd49 MS |
1934 | |
1935 | /* | |
1936 | * We should make sure that the page is already on the free list | |
1937 | * when it is dissolved. | |
1938 | */ | |
6c037149 | 1939 | if (unlikely(!HPageFreed(head))) { |
db71ef79 | 1940 | spin_unlock_irq(&hugetlb_lock); |
7ffddd49 MS |
1941 | cond_resched(); |
1942 | ||
1943 | /* | |
1944 | * Theoretically, we should return -EBUSY when we | |
1945 | * encounter this race. In fact, we have a chance | |
1946 | * to successfully dissolve the page if we do a | |
1947 | * retry. Because the race window is quite small. | |
1948 | * If we seize this opportunity, it is an optimization | |
1949 | * for increasing the success rate of dissolving page. | |
1950 | */ | |
1951 | goto retry; | |
1952 | } | |
1953 | ||
0c5da357 | 1954 | remove_hugetlb_page(h, head, false); |
c1470b33 | 1955 | h->max_huge_pages--; |
db71ef79 | 1956 | spin_unlock_irq(&hugetlb_lock); |
ad2fa371 MS |
1957 | |
1958 | /* | |
1959 | * Normally update_and_free_page will allocate required vmemmmap | |
1960 | * before freeing the page. update_and_free_page will fail to | |
1961 | * free the page if it can not allocate required vmemmap. We | |
1962 | * need to adjust max_huge_pages if the page is not freed. | |
1963 | * Attempt to allocate vmemmmap here so that we can take | |
1964 | * appropriate action on failure. | |
1965 | */ | |
1966 | rc = alloc_huge_page_vmemmap(h, head); | |
1967 | if (!rc) { | |
1968 | /* | |
1969 | * Move PageHWPoison flag from head page to the raw | |
1970 | * error page, which makes any subpages rather than | |
1971 | * the error page reusable. | |
1972 | */ | |
1973 | if (PageHWPoison(head) && page != head) { | |
1974 | SetPageHWPoison(page); | |
1975 | ClearPageHWPoison(head); | |
1976 | } | |
1977 | update_and_free_page(h, head, false); | |
1978 | } else { | |
1979 | spin_lock_irq(&hugetlb_lock); | |
1980 | add_hugetlb_page(h, head, false); | |
1981 | h->max_huge_pages++; | |
1982 | spin_unlock_irq(&hugetlb_lock); | |
1983 | } | |
1984 | ||
1985 | return rc; | |
c8721bbb | 1986 | } |
082d5b6b | 1987 | out: |
db71ef79 | 1988 | spin_unlock_irq(&hugetlb_lock); |
082d5b6b | 1989 | return rc; |
c8721bbb NH |
1990 | } |
1991 | ||
1992 | /* | |
1993 | * Dissolve free hugepages in a given pfn range. Used by memory hotplug to | |
1994 | * make specified memory blocks removable from the system. | |
2247bb33 GS |
1995 | * Note that this will dissolve a free gigantic hugepage completely, if any |
1996 | * part of it lies within the given range. | |
082d5b6b GS |
1997 | * Also note that if dissolve_free_huge_page() returns with an error, all |
1998 | * free hugepages that were dissolved before that error are lost. | |
c8721bbb | 1999 | */ |
082d5b6b | 2000 | int dissolve_free_huge_pages(unsigned long start_pfn, unsigned long end_pfn) |
c8721bbb | 2001 | { |
c8721bbb | 2002 | unsigned long pfn; |
eb03aa00 | 2003 | struct page *page; |
082d5b6b | 2004 | int rc = 0; |
c8721bbb | 2005 | |
d0177639 | 2006 | if (!hugepages_supported()) |
082d5b6b | 2007 | return rc; |
d0177639 | 2008 | |
eb03aa00 GS |
2009 | for (pfn = start_pfn; pfn < end_pfn; pfn += 1 << minimum_order) { |
2010 | page = pfn_to_page(pfn); | |
faf53def NH |
2011 | rc = dissolve_free_huge_page(page); |
2012 | if (rc) | |
2013 | break; | |
eb03aa00 | 2014 | } |
082d5b6b GS |
2015 | |
2016 | return rc; | |
c8721bbb NH |
2017 | } |
2018 | ||
ab5ac90a MH |
2019 | /* |
2020 | * Allocates a fresh surplus page from the page allocator. | |
2021 | */ | |
0c397dae | 2022 | static struct page *alloc_surplus_huge_page(struct hstate *h, gfp_t gfp_mask, |
aaf14e40 | 2023 | int nid, nodemask_t *nmask) |
7893d1d5 | 2024 | { |
9980d744 | 2025 | struct page *page = NULL; |
7893d1d5 | 2026 | |
bae7f4ae | 2027 | if (hstate_is_gigantic(h)) |
aa888a74 AK |
2028 | return NULL; |
2029 | ||
db71ef79 | 2030 | spin_lock_irq(&hugetlb_lock); |
9980d744 MH |
2031 | if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages) |
2032 | goto out_unlock; | |
db71ef79 | 2033 | spin_unlock_irq(&hugetlb_lock); |
d1c3fb1f | 2034 | |
f60858f9 | 2035 | page = alloc_fresh_huge_page(h, gfp_mask, nid, nmask, NULL); |
9980d744 | 2036 | if (!page) |
0c397dae | 2037 | return NULL; |
d1c3fb1f | 2038 | |
db71ef79 | 2039 | spin_lock_irq(&hugetlb_lock); |
9980d744 MH |
2040 | /* |
2041 | * We could have raced with the pool size change. | |
2042 | * Double check that and simply deallocate the new page | |
2043 | * if we would end up overcommiting the surpluses. Abuse | |
2044 | * temporary page to workaround the nasty free_huge_page | |
2045 | * codeflow | |
2046 | */ | |
2047 | if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages) { | |
9157c311 | 2048 | SetHPageTemporary(page); |
db71ef79 | 2049 | spin_unlock_irq(&hugetlb_lock); |
9980d744 | 2050 | put_page(page); |
2bf753e6 | 2051 | return NULL; |
9980d744 | 2052 | } else { |
9980d744 | 2053 | h->surplus_huge_pages++; |
4704dea3 | 2054 | h->surplus_huge_pages_node[page_to_nid(page)]++; |
7893d1d5 | 2055 | } |
9980d744 MH |
2056 | |
2057 | out_unlock: | |
db71ef79 | 2058 | spin_unlock_irq(&hugetlb_lock); |
7893d1d5 AL |
2059 | |
2060 | return page; | |
2061 | } | |
2062 | ||
bbe88753 | 2063 | static struct page *alloc_migrate_huge_page(struct hstate *h, gfp_t gfp_mask, |
9a4e9f3b | 2064 | int nid, nodemask_t *nmask) |
ab5ac90a MH |
2065 | { |
2066 | struct page *page; | |
2067 | ||
2068 | if (hstate_is_gigantic(h)) | |
2069 | return NULL; | |
2070 | ||
f60858f9 | 2071 | page = alloc_fresh_huge_page(h, gfp_mask, nid, nmask, NULL); |
ab5ac90a MH |
2072 | if (!page) |
2073 | return NULL; | |
2074 | ||
2075 | /* | |
2076 | * We do not account these pages as surplus because they are only | |
2077 | * temporary and will be released properly on the last reference | |
2078 | */ | |
9157c311 | 2079 | SetHPageTemporary(page); |
ab5ac90a MH |
2080 | |
2081 | return page; | |
2082 | } | |
2083 | ||
099730d6 DH |
2084 | /* |
2085 | * Use the VMA's mpolicy to allocate a huge page from the buddy. | |
2086 | */ | |
e0ec90ee | 2087 | static |
0c397dae | 2088 | struct page *alloc_buddy_huge_page_with_mpol(struct hstate *h, |
099730d6 DH |
2089 | struct vm_area_struct *vma, unsigned long addr) |
2090 | { | |
aaf14e40 MH |
2091 | struct page *page; |
2092 | struct mempolicy *mpol; | |
2093 | gfp_t gfp_mask = htlb_alloc_mask(h); | |
2094 | int nid; | |
2095 | nodemask_t *nodemask; | |
2096 | ||
2097 | nid = huge_node(vma, addr, gfp_mask, &mpol, &nodemask); | |
0c397dae | 2098 | page = alloc_surplus_huge_page(h, gfp_mask, nid, nodemask); |
aaf14e40 MH |
2099 | mpol_cond_put(mpol); |
2100 | ||
2101 | return page; | |
099730d6 DH |
2102 | } |
2103 | ||
ab5ac90a | 2104 | /* page migration callback function */ |
3e59fcb0 | 2105 | struct page *alloc_huge_page_nodemask(struct hstate *h, int preferred_nid, |
d92bbc27 | 2106 | nodemask_t *nmask, gfp_t gfp_mask) |
4db9b2ef | 2107 | { |
db71ef79 | 2108 | spin_lock_irq(&hugetlb_lock); |
4db9b2ef | 2109 | if (h->free_huge_pages - h->resv_huge_pages > 0) { |
3e59fcb0 MH |
2110 | struct page *page; |
2111 | ||
2112 | page = dequeue_huge_page_nodemask(h, gfp_mask, preferred_nid, nmask); | |
2113 | if (page) { | |
db71ef79 | 2114 | spin_unlock_irq(&hugetlb_lock); |
3e59fcb0 | 2115 | return page; |
4db9b2ef MH |
2116 | } |
2117 | } | |
db71ef79 | 2118 | spin_unlock_irq(&hugetlb_lock); |
4db9b2ef | 2119 | |
0c397dae | 2120 | return alloc_migrate_huge_page(h, gfp_mask, preferred_nid, nmask); |
4db9b2ef MH |
2121 | } |
2122 | ||
ebd63723 | 2123 | /* mempolicy aware migration callback */ |
389c8178 MH |
2124 | struct page *alloc_huge_page_vma(struct hstate *h, struct vm_area_struct *vma, |
2125 | unsigned long address) | |
ebd63723 MH |
2126 | { |
2127 | struct mempolicy *mpol; | |
2128 | nodemask_t *nodemask; | |
2129 | struct page *page; | |
ebd63723 MH |
2130 | gfp_t gfp_mask; |
2131 | int node; | |
2132 | ||
ebd63723 MH |
2133 | gfp_mask = htlb_alloc_mask(h); |
2134 | node = huge_node(vma, address, gfp_mask, &mpol, &nodemask); | |
d92bbc27 | 2135 | page = alloc_huge_page_nodemask(h, node, nodemask, gfp_mask); |
ebd63723 MH |
2136 | mpol_cond_put(mpol); |
2137 | ||
2138 | return page; | |
2139 | } | |
2140 | ||
e4e574b7 | 2141 | /* |
25985edc | 2142 | * Increase the hugetlb pool such that it can accommodate a reservation |
e4e574b7 AL |
2143 | * of size 'delta'. |
2144 | */ | |
0a4f3d1b | 2145 | static int gather_surplus_pages(struct hstate *h, long delta) |
1b2a1e7b | 2146 | __must_hold(&hugetlb_lock) |
e4e574b7 AL |
2147 | { |
2148 | struct list_head surplus_list; | |
2149 | struct page *page, *tmp; | |
0a4f3d1b LX |
2150 | int ret; |
2151 | long i; | |
2152 | long needed, allocated; | |
28073b02 | 2153 | bool alloc_ok = true; |
e4e574b7 | 2154 | |
9487ca60 | 2155 | lockdep_assert_held(&hugetlb_lock); |
a5516438 | 2156 | needed = (h->resv_huge_pages + delta) - h->free_huge_pages; |
ac09b3a1 | 2157 | if (needed <= 0) { |
a5516438 | 2158 | h->resv_huge_pages += delta; |
e4e574b7 | 2159 | return 0; |
ac09b3a1 | 2160 | } |
e4e574b7 AL |
2161 | |
2162 | allocated = 0; | |
2163 | INIT_LIST_HEAD(&surplus_list); | |
2164 | ||
2165 | ret = -ENOMEM; | |
2166 | retry: | |
db71ef79 | 2167 | spin_unlock_irq(&hugetlb_lock); |
e4e574b7 | 2168 | for (i = 0; i < needed; i++) { |
0c397dae | 2169 | page = alloc_surplus_huge_page(h, htlb_alloc_mask(h), |
aaf14e40 | 2170 | NUMA_NO_NODE, NULL); |
28073b02 HD |
2171 | if (!page) { |
2172 | alloc_ok = false; | |
2173 | break; | |
2174 | } | |
e4e574b7 | 2175 | list_add(&page->lru, &surplus_list); |
69ed779a | 2176 | cond_resched(); |
e4e574b7 | 2177 | } |
28073b02 | 2178 | allocated += i; |
e4e574b7 AL |
2179 | |
2180 | /* | |
2181 | * After retaking hugetlb_lock, we need to recalculate 'needed' | |
2182 | * because either resv_huge_pages or free_huge_pages may have changed. | |
2183 | */ | |
db71ef79 | 2184 | spin_lock_irq(&hugetlb_lock); |
a5516438 AK |
2185 | needed = (h->resv_huge_pages + delta) - |
2186 | (h->free_huge_pages + allocated); | |
28073b02 HD |
2187 | if (needed > 0) { |
2188 | if (alloc_ok) | |
2189 | goto retry; | |
2190 | /* | |
2191 | * We were not able to allocate enough pages to | |
2192 | * satisfy the entire reservation so we free what | |
2193 | * we've allocated so far. | |
2194 | */ | |
2195 | goto free; | |
2196 | } | |
e4e574b7 AL |
2197 | /* |
2198 | * The surplus_list now contains _at_least_ the number of extra pages | |
25985edc | 2199 | * needed to accommodate the reservation. Add the appropriate number |
e4e574b7 | 2200 | * of pages to the hugetlb pool and free the extras back to the buddy |
ac09b3a1 AL |
2201 | * allocator. Commit the entire reservation here to prevent another |
2202 | * process from stealing the pages as they are added to the pool but | |
2203 | * before they are reserved. | |
e4e574b7 AL |
2204 | */ |
2205 | needed += allocated; | |
a5516438 | 2206 | h->resv_huge_pages += delta; |
e4e574b7 | 2207 | ret = 0; |
a9869b83 | 2208 | |
19fc3f0a | 2209 | /* Free the needed pages to the hugetlb pool */ |
e4e574b7 | 2210 | list_for_each_entry_safe(page, tmp, &surplus_list, lru) { |
e558464b MS |
2211 | int zeroed; |
2212 | ||
19fc3f0a AL |
2213 | if ((--needed) < 0) |
2214 | break; | |
a9869b83 NH |
2215 | /* |
2216 | * This page is now managed by the hugetlb allocator and has | |
2217 | * no users -- drop the buddy allocator's reference. | |
2218 | */ | |
e558464b MS |
2219 | zeroed = put_page_testzero(page); |
2220 | VM_BUG_ON_PAGE(!zeroed, page); | |
a5516438 | 2221 | enqueue_huge_page(h, page); |
19fc3f0a | 2222 | } |
28073b02 | 2223 | free: |
db71ef79 | 2224 | spin_unlock_irq(&hugetlb_lock); |
19fc3f0a AL |
2225 | |
2226 | /* Free unnecessary surplus pages to the buddy allocator */ | |
c0d934ba JK |
2227 | list_for_each_entry_safe(page, tmp, &surplus_list, lru) |
2228 | put_page(page); | |
db71ef79 | 2229 | spin_lock_irq(&hugetlb_lock); |
e4e574b7 AL |
2230 | |
2231 | return ret; | |
2232 | } | |
2233 | ||
2234 | /* | |
e5bbc8a6 MK |
2235 | * This routine has two main purposes: |
2236 | * 1) Decrement the reservation count (resv_huge_pages) by the value passed | |
2237 | * in unused_resv_pages. This corresponds to the prior adjustments made | |
2238 | * to the associated reservation map. | |
2239 | * 2) Free any unused surplus pages that may have been allocated to satisfy | |
2240 | * the reservation. As many as unused_resv_pages may be freed. | |
e4e574b7 | 2241 | */ |
a5516438 AK |
2242 | static void return_unused_surplus_pages(struct hstate *h, |
2243 | unsigned long unused_resv_pages) | |
e4e574b7 | 2244 | { |
e4e574b7 | 2245 | unsigned long nr_pages; |
10c6ec49 MK |
2246 | struct page *page; |
2247 | LIST_HEAD(page_list); | |
2248 | ||
9487ca60 | 2249 | lockdep_assert_held(&hugetlb_lock); |
10c6ec49 MK |
2250 | /* Uncommit the reservation */ |
2251 | h->resv_huge_pages -= unused_resv_pages; | |
e4e574b7 | 2252 | |
aa888a74 | 2253 | /* Cannot return gigantic pages currently */ |
bae7f4ae | 2254 | if (hstate_is_gigantic(h)) |
e5bbc8a6 | 2255 | goto out; |
aa888a74 | 2256 | |
e5bbc8a6 MK |
2257 | /* |
2258 | * Part (or even all) of the reservation could have been backed | |
2259 | * by pre-allocated pages. Only free surplus pages. | |
2260 | */ | |
a5516438 | 2261 | nr_pages = min(unused_resv_pages, h->surplus_huge_pages); |
e4e574b7 | 2262 | |
685f3457 LS |
2263 | /* |
2264 | * We want to release as many surplus pages as possible, spread | |
9b5e5d0f LS |
2265 | * evenly across all nodes with memory. Iterate across these nodes |
2266 | * until we can no longer free unreserved surplus pages. This occurs | |
2267 | * when the nodes with surplus pages have no free pages. | |
10c6ec49 | 2268 | * remove_pool_huge_page() will balance the freed pages across the |
9b5e5d0f | 2269 | * on-line nodes with memory and will handle the hstate accounting. |
685f3457 LS |
2270 | */ |
2271 | while (nr_pages--) { | |
10c6ec49 MK |
2272 | page = remove_pool_huge_page(h, &node_states[N_MEMORY], 1); |
2273 | if (!page) | |
e5bbc8a6 | 2274 | goto out; |
10c6ec49 MK |
2275 | |
2276 | list_add(&page->lru, &page_list); | |
e4e574b7 | 2277 | } |
e5bbc8a6 MK |
2278 | |
2279 | out: | |
db71ef79 | 2280 | spin_unlock_irq(&hugetlb_lock); |
10c6ec49 | 2281 | update_and_free_pages_bulk(h, &page_list); |
db71ef79 | 2282 | spin_lock_irq(&hugetlb_lock); |
e4e574b7 AL |
2283 | } |
2284 | ||
5e911373 | 2285 | |
c37f9fb1 | 2286 | /* |
feba16e2 | 2287 | * vma_needs_reservation, vma_commit_reservation and vma_end_reservation |
5e911373 | 2288 | * are used by the huge page allocation routines to manage reservations. |
cf3ad20b MK |
2289 | * |
2290 | * vma_needs_reservation is called to determine if the huge page at addr | |
2291 | * within the vma has an associated reservation. If a reservation is | |
2292 | * needed, the value 1 is returned. The caller is then responsible for | |
2293 | * managing the global reservation and subpool usage counts. After | |
2294 | * the huge page has been allocated, vma_commit_reservation is called | |
feba16e2 MK |
2295 | * to add the page to the reservation map. If the page allocation fails, |
2296 | * the reservation must be ended instead of committed. vma_end_reservation | |
2297 | * is called in such cases. | |
cf3ad20b MK |
2298 | * |
2299 | * In the normal case, vma_commit_reservation returns the same value | |
2300 | * as the preceding vma_needs_reservation call. The only time this | |
2301 | * is not the case is if a reserve map was changed between calls. It | |
2302 | * is the responsibility of the caller to notice the difference and | |
2303 | * take appropriate action. | |
96b96a96 MK |
2304 | * |
2305 | * vma_add_reservation is used in error paths where a reservation must | |
2306 | * be restored when a newly allocated huge page must be freed. It is | |
2307 | * to be called after calling vma_needs_reservation to determine if a | |
2308 | * reservation exists. | |
846be085 MK |
2309 | * |
2310 | * vma_del_reservation is used in error paths where an entry in the reserve | |
2311 | * map was created during huge page allocation and must be removed. It is to | |
2312 | * be called after calling vma_needs_reservation to determine if a reservation | |
2313 | * exists. | |
c37f9fb1 | 2314 | */ |
5e911373 MK |
2315 | enum vma_resv_mode { |
2316 | VMA_NEEDS_RESV, | |
2317 | VMA_COMMIT_RESV, | |
feba16e2 | 2318 | VMA_END_RESV, |
96b96a96 | 2319 | VMA_ADD_RESV, |
846be085 | 2320 | VMA_DEL_RESV, |
5e911373 | 2321 | }; |
cf3ad20b MK |
2322 | static long __vma_reservation_common(struct hstate *h, |
2323 | struct vm_area_struct *vma, unsigned long addr, | |
5e911373 | 2324 | enum vma_resv_mode mode) |
c37f9fb1 | 2325 | { |
4e35f483 JK |
2326 | struct resv_map *resv; |
2327 | pgoff_t idx; | |
cf3ad20b | 2328 | long ret; |
0db9d74e | 2329 | long dummy_out_regions_needed; |
c37f9fb1 | 2330 | |
4e35f483 JK |
2331 | resv = vma_resv_map(vma); |
2332 | if (!resv) | |
84afd99b | 2333 | return 1; |
c37f9fb1 | 2334 | |
4e35f483 | 2335 | idx = vma_hugecache_offset(h, vma, addr); |
5e911373 MK |
2336 | switch (mode) { |
2337 | case VMA_NEEDS_RESV: | |
0db9d74e MA |
2338 | ret = region_chg(resv, idx, idx + 1, &dummy_out_regions_needed); |
2339 | /* We assume that vma_reservation_* routines always operate on | |
2340 | * 1 page, and that adding to resv map a 1 page entry can only | |
2341 | * ever require 1 region. | |
2342 | */ | |
2343 | VM_BUG_ON(dummy_out_regions_needed != 1); | |
5e911373 MK |
2344 | break; |
2345 | case VMA_COMMIT_RESV: | |
075a61d0 | 2346 | ret = region_add(resv, idx, idx + 1, 1, NULL, NULL); |
0db9d74e MA |
2347 | /* region_add calls of range 1 should never fail. */ |
2348 | VM_BUG_ON(ret < 0); | |
5e911373 | 2349 | break; |
feba16e2 | 2350 | case VMA_END_RESV: |
0db9d74e | 2351 | region_abort(resv, idx, idx + 1, 1); |
5e911373 MK |
2352 | ret = 0; |
2353 | break; | |
96b96a96 | 2354 | case VMA_ADD_RESV: |
0db9d74e | 2355 | if (vma->vm_flags & VM_MAYSHARE) { |
075a61d0 | 2356 | ret = region_add(resv, idx, idx + 1, 1, NULL, NULL); |
0db9d74e MA |
2357 | /* region_add calls of range 1 should never fail. */ |
2358 | VM_BUG_ON(ret < 0); | |
2359 | } else { | |
2360 | region_abort(resv, idx, idx + 1, 1); | |
96b96a96 MK |
2361 | ret = region_del(resv, idx, idx + 1); |
2362 | } | |
2363 | break; | |
846be085 MK |
2364 | case VMA_DEL_RESV: |
2365 | if (vma->vm_flags & VM_MAYSHARE) { | |
2366 | region_abort(resv, idx, idx + 1, 1); | |
2367 | ret = region_del(resv, idx, idx + 1); | |
2368 | } else { | |
2369 | ret = region_add(resv, idx, idx + 1, 1, NULL, NULL); | |
2370 | /* region_add calls of range 1 should never fail. */ | |
2371 | VM_BUG_ON(ret < 0); | |
2372 | } | |
2373 | break; | |
5e911373 MK |
2374 | default: |
2375 | BUG(); | |
2376 | } | |
84afd99b | 2377 | |
846be085 | 2378 | if (vma->vm_flags & VM_MAYSHARE || mode == VMA_DEL_RESV) |
cf3ad20b | 2379 | return ret; |
bf3d12b9 ML |
2380 | /* |
2381 | * We know private mapping must have HPAGE_RESV_OWNER set. | |
2382 | * | |
2383 | * In most cases, reserves always exist for private mappings. | |
2384 | * However, a file associated with mapping could have been | |
2385 | * hole punched or truncated after reserves were consumed. | |
2386 | * As subsequent fault on such a range will not use reserves. | |
2387 | * Subtle - The reserve map for private mappings has the | |
2388 | * opposite meaning than that of shared mappings. If NO | |
2389 | * entry is in the reserve map, it means a reservation exists. | |
2390 | * If an entry exists in the reserve map, it means the | |
2391 | * reservation has already been consumed. As a result, the | |
2392 | * return value of this routine is the opposite of the | |
2393 | * value returned from reserve map manipulation routines above. | |
2394 | */ | |
2395 | if (ret > 0) | |
2396 | return 0; | |
2397 | if (ret == 0) | |
2398 | return 1; | |
2399 | return ret; | |
c37f9fb1 | 2400 | } |
cf3ad20b MK |
2401 | |
2402 | static long vma_needs_reservation(struct hstate *h, | |
a5516438 | 2403 | struct vm_area_struct *vma, unsigned long addr) |
c37f9fb1 | 2404 | { |
5e911373 | 2405 | return __vma_reservation_common(h, vma, addr, VMA_NEEDS_RESV); |
cf3ad20b | 2406 | } |
84afd99b | 2407 | |
cf3ad20b MK |
2408 | static long vma_commit_reservation(struct hstate *h, |
2409 | struct vm_area_struct *vma, unsigned long addr) | |
2410 | { | |
5e911373 MK |
2411 | return __vma_reservation_common(h, vma, addr, VMA_COMMIT_RESV); |
2412 | } | |
2413 | ||
feba16e2 | 2414 | static void vma_end_reservation(struct hstate *h, |
5e911373 MK |
2415 | struct vm_area_struct *vma, unsigned long addr) |
2416 | { | |
feba16e2 | 2417 | (void)__vma_reservation_common(h, vma, addr, VMA_END_RESV); |
c37f9fb1 AW |
2418 | } |
2419 | ||
96b96a96 MK |
2420 | static long vma_add_reservation(struct hstate *h, |
2421 | struct vm_area_struct *vma, unsigned long addr) | |
2422 | { | |
2423 | return __vma_reservation_common(h, vma, addr, VMA_ADD_RESV); | |
2424 | } | |
2425 | ||
846be085 MK |
2426 | static long vma_del_reservation(struct hstate *h, |
2427 | struct vm_area_struct *vma, unsigned long addr) | |
2428 | { | |
2429 | return __vma_reservation_common(h, vma, addr, VMA_DEL_RESV); | |
2430 | } | |
2431 | ||
96b96a96 | 2432 | /* |
846be085 MK |
2433 | * This routine is called to restore reservation information on error paths. |
2434 | * It should ONLY be called for pages allocated via alloc_huge_page(), and | |
2435 | * the hugetlb mutex should remain held when calling this routine. | |
2436 | * | |
2437 | * It handles two specific cases: | |
2438 | * 1) A reservation was in place and the page consumed the reservation. | |
2439 | * HPageRestoreReserve is set in the page. | |
2440 | * 2) No reservation was in place for the page, so HPageRestoreReserve is | |
2441 | * not set. However, alloc_huge_page always updates the reserve map. | |
2442 | * | |
2443 | * In case 1, free_huge_page later in the error path will increment the | |
2444 | * global reserve count. But, free_huge_page does not have enough context | |
2445 | * to adjust the reservation map. This case deals primarily with private | |
2446 | * mappings. Adjust the reserve map here to be consistent with global | |
2447 | * reserve count adjustments to be made by free_huge_page. Make sure the | |
2448 | * reserve map indicates there is a reservation present. | |
2449 | * | |
2450 | * In case 2, simply undo reserve map modifications done by alloc_huge_page. | |
96b96a96 | 2451 | */ |
846be085 MK |
2452 | void restore_reserve_on_error(struct hstate *h, struct vm_area_struct *vma, |
2453 | unsigned long address, struct page *page) | |
96b96a96 | 2454 | { |
846be085 | 2455 | long rc = vma_needs_reservation(h, vma, address); |
96b96a96 | 2456 | |
846be085 MK |
2457 | if (HPageRestoreReserve(page)) { |
2458 | if (unlikely(rc < 0)) | |
96b96a96 MK |
2459 | /* |
2460 | * Rare out of memory condition in reserve map | |
d6995da3 | 2461 | * manipulation. Clear HPageRestoreReserve so that |
96b96a96 MK |
2462 | * global reserve count will not be incremented |
2463 | * by free_huge_page. This will make it appear | |
2464 | * as though the reservation for this page was | |
2465 | * consumed. This may prevent the task from | |
2466 | * faulting in the page at a later time. This | |
2467 | * is better than inconsistent global huge page | |
2468 | * accounting of reserve counts. | |
2469 | */ | |
d6995da3 | 2470 | ClearHPageRestoreReserve(page); |
846be085 MK |
2471 | else if (rc) |
2472 | (void)vma_add_reservation(h, vma, address); | |
2473 | else | |
2474 | vma_end_reservation(h, vma, address); | |
2475 | } else { | |
2476 | if (!rc) { | |
2477 | /* | |
2478 | * This indicates there is an entry in the reserve map | |
2479 | * added by alloc_huge_page. We know it was added | |
2480 | * before the alloc_huge_page call, otherwise | |
2481 | * HPageRestoreReserve would be set on the page. | |
2482 | * Remove the entry so that a subsequent allocation | |
2483 | * does not consume a reservation. | |
2484 | */ | |
2485 | rc = vma_del_reservation(h, vma, address); | |
2486 | if (rc < 0) | |
96b96a96 | 2487 | /* |
846be085 MK |
2488 | * VERY rare out of memory condition. Since |
2489 | * we can not delete the entry, set | |
2490 | * HPageRestoreReserve so that the reserve | |
2491 | * count will be incremented when the page | |
2492 | * is freed. This reserve will be consumed | |
2493 | * on a subsequent allocation. | |
96b96a96 | 2494 | */ |
846be085 MK |
2495 | SetHPageRestoreReserve(page); |
2496 | } else if (rc < 0) { | |
2497 | /* | |
2498 | * Rare out of memory condition from | |
2499 | * vma_needs_reservation call. Memory allocation is | |
2500 | * only attempted if a new entry is needed. Therefore, | |
2501 | * this implies there is not an entry in the | |
2502 | * reserve map. | |
2503 | * | |
2504 | * For shared mappings, no entry in the map indicates | |
2505 | * no reservation. We are done. | |
2506 | */ | |
2507 | if (!(vma->vm_flags & VM_MAYSHARE)) | |
2508 | /* | |
2509 | * For private mappings, no entry indicates | |
2510 | * a reservation is present. Since we can | |
2511 | * not add an entry, set SetHPageRestoreReserve | |
2512 | * on the page so reserve count will be | |
2513 | * incremented when freed. This reserve will | |
2514 | * be consumed on a subsequent allocation. | |
2515 | */ | |
2516 | SetHPageRestoreReserve(page); | |
96b96a96 | 2517 | } else |
846be085 MK |
2518 | /* |
2519 | * No reservation present, do nothing | |
2520 | */ | |
2521 | vma_end_reservation(h, vma, address); | |
96b96a96 MK |
2522 | } |
2523 | } | |
2524 | ||
369fa227 OS |
2525 | /* |
2526 | * alloc_and_dissolve_huge_page - Allocate a new page and dissolve the old one | |
2527 | * @h: struct hstate old page belongs to | |
2528 | * @old_page: Old page to dissolve | |
ae37c7ff | 2529 | * @list: List to isolate the page in case we need to |
369fa227 OS |
2530 | * Returns 0 on success, otherwise negated error. |
2531 | */ | |
ae37c7ff OS |
2532 | static int alloc_and_dissolve_huge_page(struct hstate *h, struct page *old_page, |
2533 | struct list_head *list) | |
369fa227 OS |
2534 | { |
2535 | gfp_t gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE; | |
2536 | int nid = page_to_nid(old_page); | |
2537 | struct page *new_page; | |
2538 | int ret = 0; | |
2539 | ||
2540 | /* | |
2541 | * Before dissolving the page, we need to allocate a new one for the | |
f41f2ed4 MS |
2542 | * pool to remain stable. Here, we allocate the page and 'prep' it |
2543 | * by doing everything but actually updating counters and adding to | |
2544 | * the pool. This simplifies and let us do most of the processing | |
2545 | * under the lock. | |
369fa227 OS |
2546 | */ |
2547 | new_page = alloc_buddy_huge_page(h, gfp_mask, nid, NULL, NULL); | |
2548 | if (!new_page) | |
2549 | return -ENOMEM; | |
f41f2ed4 | 2550 | __prep_new_huge_page(h, new_page); |
369fa227 OS |
2551 | |
2552 | retry: | |
2553 | spin_lock_irq(&hugetlb_lock); | |
2554 | if (!PageHuge(old_page)) { | |
2555 | /* | |
2556 | * Freed from under us. Drop new_page too. | |
2557 | */ | |
2558 | goto free_new; | |
2559 | } else if (page_count(old_page)) { | |
2560 | /* | |
ae37c7ff OS |
2561 | * Someone has grabbed the page, try to isolate it here. |
2562 | * Fail with -EBUSY if not possible. | |
369fa227 | 2563 | */ |
ae37c7ff OS |
2564 | spin_unlock_irq(&hugetlb_lock); |
2565 | if (!isolate_huge_page(old_page, list)) | |
2566 | ret = -EBUSY; | |
2567 | spin_lock_irq(&hugetlb_lock); | |
369fa227 OS |
2568 | goto free_new; |
2569 | } else if (!HPageFreed(old_page)) { | |
2570 | /* | |
2571 | * Page's refcount is 0 but it has not been enqueued in the | |
2572 | * freelist yet. Race window is small, so we can succeed here if | |
2573 | * we retry. | |
2574 | */ | |
2575 | spin_unlock_irq(&hugetlb_lock); | |
2576 | cond_resched(); | |
2577 | goto retry; | |
2578 | } else { | |
2579 | /* | |
2580 | * Ok, old_page is still a genuine free hugepage. Remove it from | |
2581 | * the freelist and decrease the counters. These will be | |
2582 | * incremented again when calling __prep_account_new_huge_page() | |
2583 | * and enqueue_huge_page() for new_page. The counters will remain | |
2584 | * stable since this happens under the lock. | |
2585 | */ | |
2586 | remove_hugetlb_page(h, old_page, false); | |
2587 | ||
2588 | /* | |
369fa227 OS |
2589 | * Reference count trick is needed because allocator gives us |
2590 | * referenced page but the pool requires pages with 0 refcount. | |
2591 | */ | |
369fa227 OS |
2592 | __prep_account_new_huge_page(h, nid); |
2593 | page_ref_dec(new_page); | |
2594 | enqueue_huge_page(h, new_page); | |
2595 | ||
2596 | /* | |
2597 | * Pages have been replaced, we can safely free the old one. | |
2598 | */ | |
2599 | spin_unlock_irq(&hugetlb_lock); | |
b65d4adb | 2600 | update_and_free_page(h, old_page, false); |
369fa227 OS |
2601 | } |
2602 | ||
2603 | return ret; | |
2604 | ||
2605 | free_new: | |
2606 | spin_unlock_irq(&hugetlb_lock); | |
b65d4adb | 2607 | update_and_free_page(h, new_page, false); |
369fa227 OS |
2608 | |
2609 | return ret; | |
2610 | } | |
2611 | ||
ae37c7ff | 2612 | int isolate_or_dissolve_huge_page(struct page *page, struct list_head *list) |
369fa227 OS |
2613 | { |
2614 | struct hstate *h; | |
2615 | struct page *head; | |
ae37c7ff | 2616 | int ret = -EBUSY; |
369fa227 OS |
2617 | |
2618 | /* | |
2619 | * The page might have been dissolved from under our feet, so make sure | |
2620 | * to carefully check the state under the lock. | |
2621 | * Return success when racing as if we dissolved the page ourselves. | |
2622 | */ | |
2623 | spin_lock_irq(&hugetlb_lock); | |
2624 | if (PageHuge(page)) { | |
2625 | head = compound_head(page); | |
2626 | h = page_hstate(head); | |
2627 | } else { | |
2628 | spin_unlock_irq(&hugetlb_lock); | |
2629 | return 0; | |
2630 | } | |
2631 | spin_unlock_irq(&hugetlb_lock); | |
2632 | ||
2633 | /* | |
2634 | * Fence off gigantic pages as there is a cyclic dependency between | |
2635 | * alloc_contig_range and them. Return -ENOMEM as this has the effect | |
2636 | * of bailing out right away without further retrying. | |
2637 | */ | |
2638 | if (hstate_is_gigantic(h)) | |
2639 | return -ENOMEM; | |
2640 | ||
ae37c7ff OS |
2641 | if (page_count(head) && isolate_huge_page(head, list)) |
2642 | ret = 0; | |
2643 | else if (!page_count(head)) | |
2644 | ret = alloc_and_dissolve_huge_page(h, head, list); | |
2645 | ||
2646 | return ret; | |
369fa227 OS |
2647 | } |
2648 | ||
70c3547e | 2649 | struct page *alloc_huge_page(struct vm_area_struct *vma, |
04f2cbe3 | 2650 | unsigned long addr, int avoid_reserve) |
1da177e4 | 2651 | { |
90481622 | 2652 | struct hugepage_subpool *spool = subpool_vma(vma); |
a5516438 | 2653 | struct hstate *h = hstate_vma(vma); |
348ea204 | 2654 | struct page *page; |
d85f69b0 MK |
2655 | long map_chg, map_commit; |
2656 | long gbl_chg; | |
6d76dcf4 AK |
2657 | int ret, idx; |
2658 | struct hugetlb_cgroup *h_cg; | |
08cf9faf | 2659 | bool deferred_reserve; |
a1e78772 | 2660 | |
6d76dcf4 | 2661 | idx = hstate_index(h); |
a1e78772 | 2662 | /* |
d85f69b0 MK |
2663 | * Examine the region/reserve map to determine if the process |
2664 | * has a reservation for the page to be allocated. A return | |
2665 | * code of zero indicates a reservation exists (no change). | |
a1e78772 | 2666 | */ |
d85f69b0 MK |
2667 | map_chg = gbl_chg = vma_needs_reservation(h, vma, addr); |
2668 | if (map_chg < 0) | |
76dcee75 | 2669 | return ERR_PTR(-ENOMEM); |
d85f69b0 MK |
2670 | |
2671 | /* | |
2672 | * Processes that did not create the mapping will have no | |
2673 | * reserves as indicated by the region/reserve map. Check | |
2674 | * that the allocation will not exceed the subpool limit. | |
2675 | * Allocations for MAP_NORESERVE mappings also need to be | |
2676 | * checked against any subpool limit. | |
2677 | */ | |
2678 | if (map_chg || avoid_reserve) { | |
2679 | gbl_chg = hugepage_subpool_get_pages(spool, 1); | |
2680 | if (gbl_chg < 0) { | |
feba16e2 | 2681 | vma_end_reservation(h, vma, addr); |
76dcee75 | 2682 | return ERR_PTR(-ENOSPC); |
5e911373 | 2683 | } |
1da177e4 | 2684 | |
d85f69b0 MK |
2685 | /* |
2686 | * Even though there was no reservation in the region/reserve | |
2687 | * map, there could be reservations associated with the | |
2688 | * subpool that can be used. This would be indicated if the | |
2689 | * return value of hugepage_subpool_get_pages() is zero. | |
2690 | * However, if avoid_reserve is specified we still avoid even | |
2691 | * the subpool reservations. | |
2692 | */ | |
2693 | if (avoid_reserve) | |
2694 | gbl_chg = 1; | |
2695 | } | |
2696 | ||
08cf9faf MA |
2697 | /* If this allocation is not consuming a reservation, charge it now. |
2698 | */ | |
6501fe5f | 2699 | deferred_reserve = map_chg || avoid_reserve; |
08cf9faf MA |
2700 | if (deferred_reserve) { |
2701 | ret = hugetlb_cgroup_charge_cgroup_rsvd( | |
2702 | idx, pages_per_huge_page(h), &h_cg); | |
2703 | if (ret) | |
2704 | goto out_subpool_put; | |
2705 | } | |
2706 | ||
6d76dcf4 | 2707 | ret = hugetlb_cgroup_charge_cgroup(idx, pages_per_huge_page(h), &h_cg); |
8f34af6f | 2708 | if (ret) |
08cf9faf | 2709 | goto out_uncharge_cgroup_reservation; |
8f34af6f | 2710 | |
db71ef79 | 2711 | spin_lock_irq(&hugetlb_lock); |
d85f69b0 MK |
2712 | /* |
2713 | * glb_chg is passed to indicate whether or not a page must be taken | |
2714 | * from the global free pool (global change). gbl_chg == 0 indicates | |
2715 | * a reservation exists for the allocation. | |
2716 | */ | |
2717 | page = dequeue_huge_page_vma(h, vma, addr, avoid_reserve, gbl_chg); | |
81a6fcae | 2718 | if (!page) { |
db71ef79 | 2719 | spin_unlock_irq(&hugetlb_lock); |
0c397dae | 2720 | page = alloc_buddy_huge_page_with_mpol(h, vma, addr); |
8f34af6f JZ |
2721 | if (!page) |
2722 | goto out_uncharge_cgroup; | |
a88c7695 | 2723 | if (!avoid_reserve && vma_has_reserves(vma, gbl_chg)) { |
d6995da3 | 2724 | SetHPageRestoreReserve(page); |
a88c7695 NH |
2725 | h->resv_huge_pages--; |
2726 | } | |
db71ef79 | 2727 | spin_lock_irq(&hugetlb_lock); |
15a8d68e | 2728 | list_add(&page->lru, &h->hugepage_activelist); |
81a6fcae | 2729 | /* Fall through */ |
68842c9b | 2730 | } |
81a6fcae | 2731 | hugetlb_cgroup_commit_charge(idx, pages_per_huge_page(h), h_cg, page); |
08cf9faf MA |
2732 | /* If allocation is not consuming a reservation, also store the |
2733 | * hugetlb_cgroup pointer on the page. | |
2734 | */ | |
2735 | if (deferred_reserve) { | |
2736 | hugetlb_cgroup_commit_charge_rsvd(idx, pages_per_huge_page(h), | |
2737 | h_cg, page); | |
2738 | } | |
2739 | ||
db71ef79 | 2740 | spin_unlock_irq(&hugetlb_lock); |
348ea204 | 2741 | |
d6995da3 | 2742 | hugetlb_set_page_subpool(page, spool); |
90d8b7e6 | 2743 | |
d85f69b0 MK |
2744 | map_commit = vma_commit_reservation(h, vma, addr); |
2745 | if (unlikely(map_chg > map_commit)) { | |
33039678 MK |
2746 | /* |
2747 | * The page was added to the reservation map between | |
2748 | * vma_needs_reservation and vma_commit_reservation. | |
2749 | * This indicates a race with hugetlb_reserve_pages. | |
2750 | * Adjust for the subpool count incremented above AND | |
2751 | * in hugetlb_reserve_pages for the same page. Also, | |
2752 | * the reservation count added in hugetlb_reserve_pages | |
2753 | * no longer applies. | |
2754 | */ | |
2755 | long rsv_adjust; | |
2756 | ||
2757 | rsv_adjust = hugepage_subpool_put_pages(spool, 1); | |
2758 | hugetlb_acct_memory(h, -rsv_adjust); | |
79aa925b MK |
2759 | if (deferred_reserve) |
2760 | hugetlb_cgroup_uncharge_page_rsvd(hstate_index(h), | |
2761 | pages_per_huge_page(h), page); | |
33039678 | 2762 | } |
90d8b7e6 | 2763 | return page; |
8f34af6f JZ |
2764 | |
2765 | out_uncharge_cgroup: | |
2766 | hugetlb_cgroup_uncharge_cgroup(idx, pages_per_huge_page(h), h_cg); | |
08cf9faf MA |
2767 | out_uncharge_cgroup_reservation: |
2768 | if (deferred_reserve) | |
2769 | hugetlb_cgroup_uncharge_cgroup_rsvd(idx, pages_per_huge_page(h), | |
2770 | h_cg); | |
8f34af6f | 2771 | out_subpool_put: |
d85f69b0 | 2772 | if (map_chg || avoid_reserve) |
8f34af6f | 2773 | hugepage_subpool_put_pages(spool, 1); |
feba16e2 | 2774 | vma_end_reservation(h, vma, addr); |
8f34af6f | 2775 | return ERR_PTR(-ENOSPC); |
b45b5bd6 DG |
2776 | } |
2777 | ||
e24a1307 AK |
2778 | int alloc_bootmem_huge_page(struct hstate *h) |
2779 | __attribute__ ((weak, alias("__alloc_bootmem_huge_page"))); | |
2780 | int __alloc_bootmem_huge_page(struct hstate *h) | |
aa888a74 AK |
2781 | { |
2782 | struct huge_bootmem_page *m; | |
b2261026 | 2783 | int nr_nodes, node; |
aa888a74 | 2784 | |
b2261026 | 2785 | for_each_node_mask_to_alloc(h, nr_nodes, node, &node_states[N_MEMORY]) { |
aa888a74 AK |
2786 | void *addr; |
2787 | ||
eb31d559 | 2788 | addr = memblock_alloc_try_nid_raw( |
8b89a116 | 2789 | huge_page_size(h), huge_page_size(h), |
97ad1087 | 2790 | 0, MEMBLOCK_ALLOC_ACCESSIBLE, node); |
aa888a74 AK |
2791 | if (addr) { |
2792 | /* | |
2793 | * Use the beginning of the huge page to store the | |
2794 | * huge_bootmem_page struct (until gather_bootmem | |
2795 | * puts them into the mem_map). | |
2796 | */ | |
2797 | m = addr; | |
91f47662 | 2798 | goto found; |
aa888a74 | 2799 | } |
aa888a74 AK |
2800 | } |
2801 | return 0; | |
2802 | ||
2803 | found: | |
df994ead | 2804 | BUG_ON(!IS_ALIGNED(virt_to_phys(m), huge_page_size(h))); |
aa888a74 | 2805 | /* Put them into a private list first because mem_map is not up yet */ |
330d6e48 | 2806 | INIT_LIST_HEAD(&m->list); |
aa888a74 AK |
2807 | list_add(&m->list, &huge_boot_pages); |
2808 | m->hstate = h; | |
2809 | return 1; | |
2810 | } | |
2811 | ||
48b8d744 MK |
2812 | /* |
2813 | * Put bootmem huge pages into the standard lists after mem_map is up. | |
2814 | * Note: This only applies to gigantic (order > MAX_ORDER) pages. | |
2815 | */ | |
aa888a74 AK |
2816 | static void __init gather_bootmem_prealloc(void) |
2817 | { | |
2818 | struct huge_bootmem_page *m; | |
2819 | ||
2820 | list_for_each_entry(m, &huge_boot_pages, list) { | |
40d18ebf | 2821 | struct page *page = virt_to_page(m); |
aa888a74 | 2822 | struct hstate *h = m->hstate; |
ee8f248d | 2823 | |
48b8d744 | 2824 | VM_BUG_ON(!hstate_is_gigantic(h)); |
aa888a74 | 2825 | WARN_ON(page_count(page) != 1); |
7118fc29 MK |
2826 | if (prep_compound_gigantic_page(page, huge_page_order(h))) { |
2827 | WARN_ON(PageReserved(page)); | |
2828 | prep_new_huge_page(h, page, page_to_nid(page)); | |
2829 | put_page(page); /* add to the hugepage allocator */ | |
2830 | } else { | |
2831 | free_gigantic_page(page, huge_page_order(h)); | |
2832 | pr_warn("HugeTLB page can not be used due to unexpected inflated ref count\n"); | |
2833 | } | |
af0fb9df | 2834 | |
b0320c7b | 2835 | /* |
48b8d744 MK |
2836 | * We need to restore the 'stolen' pages to totalram_pages |
2837 | * in order to fix confusing memory reports from free(1) and | |
2838 | * other side-effects, like CommitLimit going negative. | |
b0320c7b | 2839 | */ |
48b8d744 | 2840 | adjust_managed_page_count(page, pages_per_huge_page(h)); |
520495fe | 2841 | cond_resched(); |
aa888a74 AK |
2842 | } |
2843 | } | |
2844 | ||
8faa8b07 | 2845 | static void __init hugetlb_hstate_alloc_pages(struct hstate *h) |
1da177e4 LT |
2846 | { |
2847 | unsigned long i; | |
f60858f9 MK |
2848 | nodemask_t *node_alloc_noretry; |
2849 | ||
2850 | if (!hstate_is_gigantic(h)) { | |
2851 | /* | |
2852 | * Bit mask controlling how hard we retry per-node allocations. | |
2853 | * Ignore errors as lower level routines can deal with | |
2854 | * node_alloc_noretry == NULL. If this kmalloc fails at boot | |
2855 | * time, we are likely in bigger trouble. | |
2856 | */ | |
2857 | node_alloc_noretry = kmalloc(sizeof(*node_alloc_noretry), | |
2858 | GFP_KERNEL); | |
2859 | } else { | |
2860 | /* allocations done at boot time */ | |
2861 | node_alloc_noretry = NULL; | |
2862 | } | |
2863 | ||
2864 | /* bit mask controlling how hard we retry per-node allocations */ | |
2865 | if (node_alloc_noretry) | |
2866 | nodes_clear(*node_alloc_noretry); | |
a5516438 | 2867 | |
e5ff2159 | 2868 | for (i = 0; i < h->max_huge_pages; ++i) { |
bae7f4ae | 2869 | if (hstate_is_gigantic(h)) { |
dbda8fea | 2870 | if (hugetlb_cma_size) { |
cf11e85f | 2871 | pr_warn_once("HugeTLB: hugetlb_cma is enabled, skip boot time allocation\n"); |
7ecc9565 | 2872 | goto free; |
cf11e85f | 2873 | } |
aa888a74 AK |
2874 | if (!alloc_bootmem_huge_page(h)) |
2875 | break; | |
0c397dae | 2876 | } else if (!alloc_pool_huge_page(h, |
f60858f9 MK |
2877 | &node_states[N_MEMORY], |
2878 | node_alloc_noretry)) | |
1da177e4 | 2879 | break; |
69ed779a | 2880 | cond_resched(); |
1da177e4 | 2881 | } |
d715cf80 LH |
2882 | if (i < h->max_huge_pages) { |
2883 | char buf[32]; | |
2884 | ||
c6247f72 | 2885 | string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32); |
d715cf80 LH |
2886 | pr_warn("HugeTLB: allocating %lu of page size %s failed. Only allocated %lu hugepages.\n", |
2887 | h->max_huge_pages, buf, i); | |
2888 | h->max_huge_pages = i; | |
2889 | } | |
7ecc9565 | 2890 | free: |
f60858f9 | 2891 | kfree(node_alloc_noretry); |
e5ff2159 AK |
2892 | } |
2893 | ||
2894 | static void __init hugetlb_init_hstates(void) | |
2895 | { | |
2896 | struct hstate *h; | |
2897 | ||
2898 | for_each_hstate(h) { | |
641844f5 NH |
2899 | if (minimum_order > huge_page_order(h)) |
2900 | minimum_order = huge_page_order(h); | |
2901 | ||
8faa8b07 | 2902 | /* oversize hugepages were init'ed in early boot */ |
bae7f4ae | 2903 | if (!hstate_is_gigantic(h)) |
8faa8b07 | 2904 | hugetlb_hstate_alloc_pages(h); |
e5ff2159 | 2905 | } |
641844f5 | 2906 | VM_BUG_ON(minimum_order == UINT_MAX); |
e5ff2159 AK |
2907 | } |
2908 | ||
2909 | static void __init report_hugepages(void) | |
2910 | { | |
2911 | struct hstate *h; | |
2912 | ||
2913 | for_each_hstate(h) { | |
4abd32db | 2914 | char buf[32]; |
c6247f72 MW |
2915 | |
2916 | string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32); | |
ffb22af5 | 2917 | pr_info("HugeTLB registered %s page size, pre-allocated %ld pages\n", |
c6247f72 | 2918 | buf, h->free_huge_pages); |
e5ff2159 AK |
2919 | } |
2920 | } | |
2921 | ||
1da177e4 | 2922 | #ifdef CONFIG_HIGHMEM |
6ae11b27 LS |
2923 | static void try_to_free_low(struct hstate *h, unsigned long count, |
2924 | nodemask_t *nodes_allowed) | |
1da177e4 | 2925 | { |
4415cc8d | 2926 | int i; |
1121828a | 2927 | LIST_HEAD(page_list); |
4415cc8d | 2928 | |
9487ca60 | 2929 | lockdep_assert_held(&hugetlb_lock); |
bae7f4ae | 2930 | if (hstate_is_gigantic(h)) |
aa888a74 AK |
2931 | return; |
2932 | ||
1121828a MK |
2933 | /* |
2934 | * Collect pages to be freed on a list, and free after dropping lock | |
2935 | */ | |
6ae11b27 | 2936 | for_each_node_mask(i, *nodes_allowed) { |
10c6ec49 | 2937 | struct page *page, *next; |
a5516438 AK |
2938 | struct list_head *freel = &h->hugepage_freelists[i]; |
2939 | list_for_each_entry_safe(page, next, freel, lru) { | |
2940 | if (count >= h->nr_huge_pages) | |
1121828a | 2941 | goto out; |
1da177e4 LT |
2942 | if (PageHighMem(page)) |
2943 | continue; | |
6eb4e88a | 2944 | remove_hugetlb_page(h, page, false); |
1121828a | 2945 | list_add(&page->lru, &page_list); |
1da177e4 LT |
2946 | } |
2947 | } | |
1121828a MK |
2948 | |
2949 | out: | |
db71ef79 | 2950 | spin_unlock_irq(&hugetlb_lock); |
10c6ec49 | 2951 | update_and_free_pages_bulk(h, &page_list); |
db71ef79 | 2952 | spin_lock_irq(&hugetlb_lock); |
1da177e4 LT |
2953 | } |
2954 | #else | |
6ae11b27 LS |
2955 | static inline void try_to_free_low(struct hstate *h, unsigned long count, |
2956 | nodemask_t *nodes_allowed) | |
1da177e4 LT |
2957 | { |
2958 | } | |
2959 | #endif | |
2960 | ||
20a0307c WF |
2961 | /* |
2962 | * Increment or decrement surplus_huge_pages. Keep node-specific counters | |
2963 | * balanced by operating on them in a round-robin fashion. | |
2964 | * Returns 1 if an adjustment was made. | |
2965 | */ | |
6ae11b27 LS |
2966 | static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed, |
2967 | int delta) | |
20a0307c | 2968 | { |
b2261026 | 2969 | int nr_nodes, node; |
20a0307c | 2970 | |
9487ca60 | 2971 | lockdep_assert_held(&hugetlb_lock); |
20a0307c | 2972 | VM_BUG_ON(delta != -1 && delta != 1); |
20a0307c | 2973 | |
b2261026 JK |
2974 | if (delta < 0) { |
2975 | for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) { | |
2976 | if (h->surplus_huge_pages_node[node]) | |
2977 | goto found; | |
e8c5c824 | 2978 | } |
b2261026 JK |
2979 | } else { |
2980 | for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { | |
2981 | if (h->surplus_huge_pages_node[node] < | |
2982 | h->nr_huge_pages_node[node]) | |
2983 | goto found; | |
e8c5c824 | 2984 | } |
b2261026 JK |
2985 | } |
2986 | return 0; | |
20a0307c | 2987 | |
b2261026 JK |
2988 | found: |
2989 | h->surplus_huge_pages += delta; | |
2990 | h->surplus_huge_pages_node[node] += delta; | |
2991 | return 1; | |
20a0307c WF |
2992 | } |
2993 | ||
a5516438 | 2994 | #define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages) |
fd875dca | 2995 | static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid, |
4eb0716e | 2996 | nodemask_t *nodes_allowed) |
1da177e4 | 2997 | { |
7893d1d5 | 2998 | unsigned long min_count, ret; |
10c6ec49 MK |
2999 | struct page *page; |
3000 | LIST_HEAD(page_list); | |
f60858f9 MK |
3001 | NODEMASK_ALLOC(nodemask_t, node_alloc_noretry, GFP_KERNEL); |
3002 | ||
3003 | /* | |
3004 | * Bit mask controlling how hard we retry per-node allocations. | |
3005 | * If we can not allocate the bit mask, do not attempt to allocate | |
3006 | * the requested huge pages. | |
3007 | */ | |
3008 | if (node_alloc_noretry) | |
3009 | nodes_clear(*node_alloc_noretry); | |
3010 | else | |
3011 | return -ENOMEM; | |
1da177e4 | 3012 | |
29383967 MK |
3013 | /* |
3014 | * resize_lock mutex prevents concurrent adjustments to number of | |
3015 | * pages in hstate via the proc/sysfs interfaces. | |
3016 | */ | |
3017 | mutex_lock(&h->resize_lock); | |
b65d4adb | 3018 | flush_free_hpage_work(h); |
db71ef79 | 3019 | spin_lock_irq(&hugetlb_lock); |
4eb0716e | 3020 | |
fd875dca MK |
3021 | /* |
3022 | * Check for a node specific request. | |
3023 | * Changing node specific huge page count may require a corresponding | |
3024 | * change to the global count. In any case, the passed node mask | |
3025 | * (nodes_allowed) will restrict alloc/free to the specified node. | |
3026 | */ | |
3027 | if (nid != NUMA_NO_NODE) { | |
3028 | unsigned long old_count = count; | |
3029 | ||
3030 | count += h->nr_huge_pages - h->nr_huge_pages_node[nid]; | |
3031 | /* | |
3032 | * User may have specified a large count value which caused the | |
3033 | * above calculation to overflow. In this case, they wanted | |
3034 | * to allocate as many huge pages as possible. Set count to | |
3035 | * largest possible value to align with their intention. | |
3036 | */ | |
3037 | if (count < old_count) | |
3038 | count = ULONG_MAX; | |
3039 | } | |
3040 | ||
4eb0716e AG |
3041 | /* |
3042 | * Gigantic pages runtime allocation depend on the capability for large | |
3043 | * page range allocation. | |
3044 | * If the system does not provide this feature, return an error when | |
3045 | * the user tries to allocate gigantic pages but let the user free the | |
3046 | * boottime allocated gigantic pages. | |
3047 | */ | |
3048 | if (hstate_is_gigantic(h) && !IS_ENABLED(CONFIG_CONTIG_ALLOC)) { | |
3049 | if (count > persistent_huge_pages(h)) { | |
db71ef79 | 3050 | spin_unlock_irq(&hugetlb_lock); |
29383967 | 3051 | mutex_unlock(&h->resize_lock); |
f60858f9 | 3052 | NODEMASK_FREE(node_alloc_noretry); |
4eb0716e AG |
3053 | return -EINVAL; |
3054 | } | |
3055 | /* Fall through to decrease pool */ | |
3056 | } | |
aa888a74 | 3057 | |
7893d1d5 AL |
3058 | /* |
3059 | * Increase the pool size | |
3060 | * First take pages out of surplus state. Then make up the | |
3061 | * remaining difference by allocating fresh huge pages. | |
d1c3fb1f | 3062 | * |
0c397dae | 3063 | * We might race with alloc_surplus_huge_page() here and be unable |
d1c3fb1f NA |
3064 | * to convert a surplus huge page to a normal huge page. That is |
3065 | * not critical, though, it just means the overall size of the | |
3066 | * pool might be one hugepage larger than it needs to be, but | |
3067 | * within all the constraints specified by the sysctls. | |
7893d1d5 | 3068 | */ |
a5516438 | 3069 | while (h->surplus_huge_pages && count > persistent_huge_pages(h)) { |
6ae11b27 | 3070 | if (!adjust_pool_surplus(h, nodes_allowed, -1)) |
7893d1d5 AL |
3071 | break; |
3072 | } | |
3073 | ||
a5516438 | 3074 | while (count > persistent_huge_pages(h)) { |
7893d1d5 AL |
3075 | /* |
3076 | * If this allocation races such that we no longer need the | |
3077 | * page, free_huge_page will handle it by freeing the page | |
3078 | * and reducing the surplus. | |
3079 | */ | |
db71ef79 | 3080 | spin_unlock_irq(&hugetlb_lock); |
649920c6 JH |
3081 | |
3082 | /* yield cpu to avoid soft lockup */ | |
3083 | cond_resched(); | |
3084 | ||
f60858f9 MK |
3085 | ret = alloc_pool_huge_page(h, nodes_allowed, |
3086 | node_alloc_noretry); | |
db71ef79 | 3087 | spin_lock_irq(&hugetlb_lock); |
7893d1d5 AL |
3088 | if (!ret) |
3089 | goto out; | |
3090 | ||
536240f2 MG |
3091 | /* Bail for signals. Probably ctrl-c from user */ |
3092 | if (signal_pending(current)) | |
3093 | goto out; | |
7893d1d5 | 3094 | } |
7893d1d5 AL |
3095 | |
3096 | /* | |
3097 | * Decrease the pool size | |
3098 | * First return free pages to the buddy allocator (being careful | |
3099 | * to keep enough around to satisfy reservations). Then place | |
3100 | * pages into surplus state as needed so the pool will shrink | |
3101 | * to the desired size as pages become free. | |
d1c3fb1f NA |
3102 | * |
3103 | * By placing pages into the surplus state independent of the | |
3104 | * overcommit value, we are allowing the surplus pool size to | |
3105 | * exceed overcommit. There are few sane options here. Since | |
0c397dae | 3106 | * alloc_surplus_huge_page() is checking the global counter, |
d1c3fb1f NA |
3107 | * though, we'll note that we're not allowed to exceed surplus |
3108 | * and won't grow the pool anywhere else. Not until one of the | |
3109 | * sysctls are changed, or the surplus pages go out of use. | |
7893d1d5 | 3110 | */ |
a5516438 | 3111 | min_count = h->resv_huge_pages + h->nr_huge_pages - h->free_huge_pages; |
6b0c880d | 3112 | min_count = max(count, min_count); |
6ae11b27 | 3113 | try_to_free_low(h, min_count, nodes_allowed); |
10c6ec49 MK |
3114 | |
3115 | /* | |
3116 | * Collect pages to be removed on list without dropping lock | |
3117 | */ | |
a5516438 | 3118 | while (min_count < persistent_huge_pages(h)) { |
10c6ec49 MK |
3119 | page = remove_pool_huge_page(h, nodes_allowed, 0); |
3120 | if (!page) | |
1da177e4 | 3121 | break; |
10c6ec49 MK |
3122 | |
3123 | list_add(&page->lru, &page_list); | |
1da177e4 | 3124 | } |
10c6ec49 | 3125 | /* free the pages after dropping lock */ |
db71ef79 | 3126 | spin_unlock_irq(&hugetlb_lock); |
10c6ec49 | 3127 | update_and_free_pages_bulk(h, &page_list); |
b65d4adb | 3128 | flush_free_hpage_work(h); |
db71ef79 | 3129 | spin_lock_irq(&hugetlb_lock); |
10c6ec49 | 3130 | |
a5516438 | 3131 | while (count < persistent_huge_pages(h)) { |
6ae11b27 | 3132 | if (!adjust_pool_surplus(h, nodes_allowed, 1)) |
7893d1d5 AL |
3133 | break; |
3134 | } | |
3135 | out: | |
4eb0716e | 3136 | h->max_huge_pages = persistent_huge_pages(h); |
db71ef79 | 3137 | spin_unlock_irq(&hugetlb_lock); |
29383967 | 3138 | mutex_unlock(&h->resize_lock); |
4eb0716e | 3139 | |
f60858f9 MK |
3140 | NODEMASK_FREE(node_alloc_noretry); |
3141 | ||
4eb0716e | 3142 | return 0; |
1da177e4 LT |
3143 | } |
3144 | ||
a3437870 NA |
3145 | #define HSTATE_ATTR_RO(_name) \ |
3146 | static struct kobj_attribute _name##_attr = __ATTR_RO(_name) | |
3147 | ||
3148 | #define HSTATE_ATTR(_name) \ | |
3149 | static struct kobj_attribute _name##_attr = \ | |
3150 | __ATTR(_name, 0644, _name##_show, _name##_store) | |
3151 | ||
3152 | static struct kobject *hugepages_kobj; | |
3153 | static struct kobject *hstate_kobjs[HUGE_MAX_HSTATE]; | |
3154 | ||
9a305230 LS |
3155 | static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp); |
3156 | ||
3157 | static struct hstate *kobj_to_hstate(struct kobject *kobj, int *nidp) | |
a3437870 NA |
3158 | { |
3159 | int i; | |
9a305230 | 3160 | |
a3437870 | 3161 | for (i = 0; i < HUGE_MAX_HSTATE; i++) |
9a305230 LS |
3162 | if (hstate_kobjs[i] == kobj) { |
3163 | if (nidp) | |
3164 | *nidp = NUMA_NO_NODE; | |
a3437870 | 3165 | return &hstates[i]; |
9a305230 LS |
3166 | } |
3167 | ||
3168 | return kobj_to_node_hstate(kobj, nidp); | |
a3437870 NA |
3169 | } |
3170 | ||
06808b08 | 3171 | static ssize_t nr_hugepages_show_common(struct kobject *kobj, |
a3437870 NA |
3172 | struct kobj_attribute *attr, char *buf) |
3173 | { | |
9a305230 LS |
3174 | struct hstate *h; |
3175 | unsigned long nr_huge_pages; | |
3176 | int nid; | |
3177 | ||
3178 | h = kobj_to_hstate(kobj, &nid); | |
3179 | if (nid == NUMA_NO_NODE) | |
3180 | nr_huge_pages = h->nr_huge_pages; | |
3181 | else | |
3182 | nr_huge_pages = h->nr_huge_pages_node[nid]; | |
3183 | ||
ae7a927d | 3184 | return sysfs_emit(buf, "%lu\n", nr_huge_pages); |
a3437870 | 3185 | } |
adbe8726 | 3186 | |
238d3c13 DR |
3187 | static ssize_t __nr_hugepages_store_common(bool obey_mempolicy, |
3188 | struct hstate *h, int nid, | |
3189 | unsigned long count, size_t len) | |
a3437870 NA |
3190 | { |
3191 | int err; | |
2d0adf7e | 3192 | nodemask_t nodes_allowed, *n_mask; |
a3437870 | 3193 | |
2d0adf7e OS |
3194 | if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) |
3195 | return -EINVAL; | |
adbe8726 | 3196 | |
9a305230 LS |
3197 | if (nid == NUMA_NO_NODE) { |
3198 | /* | |
3199 | * global hstate attribute | |
3200 | */ | |
3201 | if (!(obey_mempolicy && | |
2d0adf7e OS |
3202 | init_nodemask_of_mempolicy(&nodes_allowed))) |
3203 | n_mask = &node_states[N_MEMORY]; | |
3204 | else | |
3205 | n_mask = &nodes_allowed; | |
3206 | } else { | |
9a305230 | 3207 | /* |
fd875dca MK |
3208 | * Node specific request. count adjustment happens in |
3209 | * set_max_huge_pages() after acquiring hugetlb_lock. | |
9a305230 | 3210 | */ |
2d0adf7e OS |
3211 | init_nodemask_of_node(&nodes_allowed, nid); |
3212 | n_mask = &nodes_allowed; | |
fd875dca | 3213 | } |
9a305230 | 3214 | |
2d0adf7e | 3215 | err = set_max_huge_pages(h, count, nid, n_mask); |
06808b08 | 3216 | |
4eb0716e | 3217 | return err ? err : len; |
06808b08 LS |
3218 | } |
3219 | ||
238d3c13 DR |
3220 | static ssize_t nr_hugepages_store_common(bool obey_mempolicy, |
3221 | struct kobject *kobj, const char *buf, | |
3222 | size_t len) | |
3223 | { | |
3224 | struct hstate *h; | |
3225 | unsigned long count; | |
3226 | int nid; | |
3227 | int err; | |
3228 | ||
3229 | err = kstrtoul(buf, 10, &count); | |
3230 | if (err) | |
3231 | return err; | |
3232 | ||
3233 | h = kobj_to_hstate(kobj, &nid); | |
3234 | return __nr_hugepages_store_common(obey_mempolicy, h, nid, count, len); | |
3235 | } | |
3236 | ||
06808b08 LS |
3237 | static ssize_t nr_hugepages_show(struct kobject *kobj, |
3238 | struct kobj_attribute *attr, char *buf) | |
3239 | { | |
3240 | return nr_hugepages_show_common(kobj, attr, buf); | |
3241 | } | |
3242 | ||
3243 | static ssize_t nr_hugepages_store(struct kobject *kobj, | |
3244 | struct kobj_attribute *attr, const char *buf, size_t len) | |
3245 | { | |
238d3c13 | 3246 | return nr_hugepages_store_common(false, kobj, buf, len); |
a3437870 NA |
3247 | } |
3248 | HSTATE_ATTR(nr_hugepages); | |
3249 | ||
06808b08 LS |
3250 | #ifdef CONFIG_NUMA |
3251 | ||
3252 | /* | |
3253 | * hstate attribute for optionally mempolicy-based constraint on persistent | |
3254 | * huge page alloc/free. | |
3255 | */ | |
3256 | static ssize_t nr_hugepages_mempolicy_show(struct kobject *kobj, | |
ae7a927d JP |
3257 | struct kobj_attribute *attr, |
3258 | char *buf) | |
06808b08 LS |
3259 | { |
3260 | return nr_hugepages_show_common(kobj, attr, buf); | |
3261 | } | |
3262 | ||
3263 | static ssize_t nr_hugepages_mempolicy_store(struct kobject *kobj, | |
3264 | struct kobj_attribute *attr, const char *buf, size_t len) | |
3265 | { | |
238d3c13 | 3266 | return nr_hugepages_store_common(true, kobj, buf, len); |
06808b08 LS |
3267 | } |
3268 | HSTATE_ATTR(nr_hugepages_mempolicy); | |
3269 | #endif | |
3270 | ||
3271 | ||
a3437870 NA |
3272 | static ssize_t nr_overcommit_hugepages_show(struct kobject *kobj, |
3273 | struct kobj_attribute *attr, char *buf) | |
3274 | { | |
9a305230 | 3275 | struct hstate *h = kobj_to_hstate(kobj, NULL); |
ae7a927d | 3276 | return sysfs_emit(buf, "%lu\n", h->nr_overcommit_huge_pages); |
a3437870 | 3277 | } |
adbe8726 | 3278 | |
a3437870 NA |
3279 | static ssize_t nr_overcommit_hugepages_store(struct kobject *kobj, |
3280 | struct kobj_attribute *attr, const char *buf, size_t count) | |
3281 | { | |
3282 | int err; | |
3283 | unsigned long input; | |
9a305230 | 3284 | struct hstate *h = kobj_to_hstate(kobj, NULL); |
a3437870 | 3285 | |
bae7f4ae | 3286 | if (hstate_is_gigantic(h)) |
adbe8726 EM |
3287 | return -EINVAL; |
3288 | ||
3dbb95f7 | 3289 | err = kstrtoul(buf, 10, &input); |
a3437870 | 3290 | if (err) |
73ae31e5 | 3291 | return err; |
a3437870 | 3292 | |
db71ef79 | 3293 | spin_lock_irq(&hugetlb_lock); |
a3437870 | 3294 | h->nr_overcommit_huge_pages = input; |
db71ef79 | 3295 | spin_unlock_irq(&hugetlb_lock); |
a3437870 NA |
3296 | |
3297 | return count; | |
3298 | } | |
3299 | HSTATE_ATTR(nr_overcommit_hugepages); | |
3300 | ||
3301 | static ssize_t free_hugepages_show(struct kobject *kobj, | |
3302 | struct kobj_attribute *attr, char *buf) | |
3303 | { | |
9a305230 LS |
3304 | struct hstate *h; |
3305 | unsigned long free_huge_pages; | |
3306 | int nid; | |
3307 | ||
3308 | h = kobj_to_hstate(kobj, &nid); | |
3309 | if (nid == NUMA_NO_NODE) | |
3310 | free_huge_pages = h->free_huge_pages; | |
3311 | else | |
3312 | free_huge_pages = h->free_huge_pages_node[nid]; | |
3313 | ||
ae7a927d | 3314 | return sysfs_emit(buf, "%lu\n", free_huge_pages); |
a3437870 NA |
3315 | } |
3316 | HSTATE_ATTR_RO(free_hugepages); | |
3317 | ||
3318 | static ssize_t resv_hugepages_show(struct kobject *kobj, | |
3319 | struct kobj_attribute *attr, char *buf) | |
3320 | { | |
9a305230 | 3321 | struct hstate *h = kobj_to_hstate(kobj, NULL); |
ae7a927d | 3322 | return sysfs_emit(buf, "%lu\n", h->resv_huge_pages); |
a3437870 NA |
3323 | } |
3324 | HSTATE_ATTR_RO(resv_hugepages); | |
3325 | ||
3326 | static ssize_t surplus_hugepages_show(struct kobject *kobj, | |
3327 | struct kobj_attribute *attr, char *buf) | |
3328 | { | |
9a305230 LS |
3329 | struct hstate *h; |
3330 | unsigned long surplus_huge_pages; | |
3331 | int nid; | |
3332 | ||
3333 | h = kobj_to_hstate(kobj, &nid); | |
3334 | if (nid == NUMA_NO_NODE) | |
3335 | surplus_huge_pages = h->surplus_huge_pages; | |
3336 | else | |
3337 | surplus_huge_pages = h->surplus_huge_pages_node[nid]; | |
3338 | ||
ae7a927d | 3339 | return sysfs_emit(buf, "%lu\n", surplus_huge_pages); |
a3437870 NA |
3340 | } |
3341 | HSTATE_ATTR_RO(surplus_hugepages); | |
3342 | ||
3343 | static struct attribute *hstate_attrs[] = { | |
3344 | &nr_hugepages_attr.attr, | |
3345 | &nr_overcommit_hugepages_attr.attr, | |
3346 | &free_hugepages_attr.attr, | |
3347 | &resv_hugepages_attr.attr, | |
3348 | &surplus_hugepages_attr.attr, | |
06808b08 LS |
3349 | #ifdef CONFIG_NUMA |
3350 | &nr_hugepages_mempolicy_attr.attr, | |
3351 | #endif | |
a3437870 NA |
3352 | NULL, |
3353 | }; | |
3354 | ||
67e5ed96 | 3355 | static const struct attribute_group hstate_attr_group = { |
a3437870 NA |
3356 | .attrs = hstate_attrs, |
3357 | }; | |
3358 | ||
094e9539 JM |
3359 | static int hugetlb_sysfs_add_hstate(struct hstate *h, struct kobject *parent, |
3360 | struct kobject **hstate_kobjs, | |
67e5ed96 | 3361 | const struct attribute_group *hstate_attr_group) |
a3437870 NA |
3362 | { |
3363 | int retval; | |
972dc4de | 3364 | int hi = hstate_index(h); |
a3437870 | 3365 | |
9a305230 LS |
3366 | hstate_kobjs[hi] = kobject_create_and_add(h->name, parent); |
3367 | if (!hstate_kobjs[hi]) | |
a3437870 NA |
3368 | return -ENOMEM; |
3369 | ||
9a305230 | 3370 | retval = sysfs_create_group(hstate_kobjs[hi], hstate_attr_group); |
cc2205a6 | 3371 | if (retval) { |
9a305230 | 3372 | kobject_put(hstate_kobjs[hi]); |
cc2205a6 ML |
3373 | hstate_kobjs[hi] = NULL; |
3374 | } | |
a3437870 NA |
3375 | |
3376 | return retval; | |
3377 | } | |
3378 | ||
3379 | static void __init hugetlb_sysfs_init(void) | |
3380 | { | |
3381 | struct hstate *h; | |
3382 | int err; | |
3383 | ||
3384 | hugepages_kobj = kobject_create_and_add("hugepages", mm_kobj); | |
3385 | if (!hugepages_kobj) | |
3386 | return; | |
3387 | ||
3388 | for_each_hstate(h) { | |
9a305230 LS |
3389 | err = hugetlb_sysfs_add_hstate(h, hugepages_kobj, |
3390 | hstate_kobjs, &hstate_attr_group); | |
a3437870 | 3391 | if (err) |
282f4214 | 3392 | pr_err("HugeTLB: Unable to add hstate %s", h->name); |
a3437870 NA |
3393 | } |
3394 | } | |
3395 | ||
9a305230 LS |
3396 | #ifdef CONFIG_NUMA |
3397 | ||
3398 | /* | |
3399 | * node_hstate/s - associate per node hstate attributes, via their kobjects, | |
10fbcf4c KS |
3400 | * with node devices in node_devices[] using a parallel array. The array |
3401 | * index of a node device or _hstate == node id. | |
3402 | * This is here to avoid any static dependency of the node device driver, in | |
9a305230 LS |
3403 | * the base kernel, on the hugetlb module. |
3404 | */ | |
3405 | struct node_hstate { | |
3406 | struct kobject *hugepages_kobj; | |
3407 | struct kobject *hstate_kobjs[HUGE_MAX_HSTATE]; | |
3408 | }; | |
b4e289a6 | 3409 | static struct node_hstate node_hstates[MAX_NUMNODES]; |
9a305230 LS |
3410 | |
3411 | /* | |
10fbcf4c | 3412 | * A subset of global hstate attributes for node devices |
9a305230 LS |
3413 | */ |
3414 | static struct attribute *per_node_hstate_attrs[] = { | |
3415 | &nr_hugepages_attr.attr, | |
3416 | &free_hugepages_attr.attr, | |
3417 | &surplus_hugepages_attr.attr, | |
3418 | NULL, | |
3419 | }; | |
3420 | ||
67e5ed96 | 3421 | static const struct attribute_group per_node_hstate_attr_group = { |
9a305230 LS |
3422 | .attrs = per_node_hstate_attrs, |
3423 | }; | |
3424 | ||
3425 | /* | |
10fbcf4c | 3426 | * kobj_to_node_hstate - lookup global hstate for node device hstate attr kobj. |
9a305230 LS |
3427 | * Returns node id via non-NULL nidp. |
3428 | */ | |
3429 | static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) | |
3430 | { | |
3431 | int nid; | |
3432 | ||
3433 | for (nid = 0; nid < nr_node_ids; nid++) { | |
3434 | struct node_hstate *nhs = &node_hstates[nid]; | |
3435 | int i; | |
3436 | for (i = 0; i < HUGE_MAX_HSTATE; i++) | |
3437 | if (nhs->hstate_kobjs[i] == kobj) { | |
3438 | if (nidp) | |
3439 | *nidp = nid; | |
3440 | return &hstates[i]; | |
3441 | } | |
3442 | } | |
3443 | ||
3444 | BUG(); | |
3445 | return NULL; | |
3446 | } | |
3447 | ||
3448 | /* | |
10fbcf4c | 3449 | * Unregister hstate attributes from a single node device. |
9a305230 LS |
3450 | * No-op if no hstate attributes attached. |
3451 | */ | |
3cd8b44f | 3452 | static void hugetlb_unregister_node(struct node *node) |
9a305230 LS |
3453 | { |
3454 | struct hstate *h; | |
10fbcf4c | 3455 | struct node_hstate *nhs = &node_hstates[node->dev.id]; |
9a305230 LS |
3456 | |
3457 | if (!nhs->hugepages_kobj) | |
9b5e5d0f | 3458 | return; /* no hstate attributes */ |
9a305230 | 3459 | |
972dc4de AK |
3460 | for_each_hstate(h) { |
3461 | int idx = hstate_index(h); | |
3462 | if (nhs->hstate_kobjs[idx]) { | |
3463 | kobject_put(nhs->hstate_kobjs[idx]); | |
3464 | nhs->hstate_kobjs[idx] = NULL; | |
9a305230 | 3465 | } |
972dc4de | 3466 | } |
9a305230 LS |
3467 | |
3468 | kobject_put(nhs->hugepages_kobj); | |
3469 | nhs->hugepages_kobj = NULL; | |
3470 | } | |
3471 | ||
9a305230 LS |
3472 | |
3473 | /* | |
10fbcf4c | 3474 | * Register hstate attributes for a single node device. |
9a305230 LS |
3475 | * No-op if attributes already registered. |
3476 | */ | |
3cd8b44f | 3477 | static void hugetlb_register_node(struct node *node) |
9a305230 LS |
3478 | { |
3479 | struct hstate *h; | |
10fbcf4c | 3480 | struct node_hstate *nhs = &node_hstates[node->dev.id]; |
9a305230 LS |
3481 | int err; |
3482 | ||
3483 | if (nhs->hugepages_kobj) | |
3484 | return; /* already allocated */ | |
3485 | ||
3486 | nhs->hugepages_kobj = kobject_create_and_add("hugepages", | |
10fbcf4c | 3487 | &node->dev.kobj); |
9a305230 LS |
3488 | if (!nhs->hugepages_kobj) |
3489 | return; | |
3490 | ||
3491 | for_each_hstate(h) { | |
3492 | err = hugetlb_sysfs_add_hstate(h, nhs->hugepages_kobj, | |
3493 | nhs->hstate_kobjs, | |
3494 | &per_node_hstate_attr_group); | |
3495 | if (err) { | |
282f4214 | 3496 | pr_err("HugeTLB: Unable to add hstate %s for node %d\n", |
ffb22af5 | 3497 | h->name, node->dev.id); |
9a305230 LS |
3498 | hugetlb_unregister_node(node); |
3499 | break; | |
3500 | } | |
3501 | } | |
3502 | } | |
3503 | ||
3504 | /* | |
9b5e5d0f | 3505 | * hugetlb init time: register hstate attributes for all registered node |
10fbcf4c KS |
3506 | * devices of nodes that have memory. All on-line nodes should have |
3507 | * registered their associated device by this time. | |
9a305230 | 3508 | */ |
7d9ca000 | 3509 | static void __init hugetlb_register_all_nodes(void) |
9a305230 LS |
3510 | { |
3511 | int nid; | |
3512 | ||
8cebfcd0 | 3513 | for_each_node_state(nid, N_MEMORY) { |
8732794b | 3514 | struct node *node = node_devices[nid]; |
10fbcf4c | 3515 | if (node->dev.id == nid) |
9a305230 LS |
3516 | hugetlb_register_node(node); |
3517 | } | |
3518 | ||
3519 | /* | |
10fbcf4c | 3520 | * Let the node device driver know we're here so it can |
9a305230 LS |
3521 | * [un]register hstate attributes on node hotplug. |
3522 | */ | |
3523 | register_hugetlbfs_with_node(hugetlb_register_node, | |
3524 | hugetlb_unregister_node); | |
3525 | } | |
3526 | #else /* !CONFIG_NUMA */ | |
3527 | ||
3528 | static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) | |
3529 | { | |
3530 | BUG(); | |
3531 | if (nidp) | |
3532 | *nidp = -1; | |
3533 | return NULL; | |
3534 | } | |
3535 | ||
9a305230 LS |
3536 | static void hugetlb_register_all_nodes(void) { } |
3537 | ||
3538 | #endif | |
3539 | ||
a3437870 NA |
3540 | static int __init hugetlb_init(void) |
3541 | { | |
8382d914 DB |
3542 | int i; |
3543 | ||
d6995da3 MK |
3544 | BUILD_BUG_ON(sizeof_field(struct page, private) * BITS_PER_BYTE < |
3545 | __NR_HPAGEFLAGS); | |
3546 | ||
c2833a5b MK |
3547 | if (!hugepages_supported()) { |
3548 | if (hugetlb_max_hstate || default_hstate_max_huge_pages) | |
3549 | pr_warn("HugeTLB: huge pages not supported, ignoring associated command-line parameters\n"); | |
0ef89d25 | 3550 | return 0; |
c2833a5b | 3551 | } |
a3437870 | 3552 | |
282f4214 MK |
3553 | /* |
3554 | * Make sure HPAGE_SIZE (HUGETLB_PAGE_ORDER) hstate exists. Some | |
3555 | * architectures depend on setup being done here. | |
3556 | */ | |
3557 | hugetlb_add_hstate(HUGETLB_PAGE_ORDER); | |
3558 | if (!parsed_default_hugepagesz) { | |
3559 | /* | |
3560 | * If we did not parse a default huge page size, set | |
3561 | * default_hstate_idx to HPAGE_SIZE hstate. And, if the | |
3562 | * number of huge pages for this default size was implicitly | |
3563 | * specified, set that here as well. | |
3564 | * Note that the implicit setting will overwrite an explicit | |
3565 | * setting. A warning will be printed in this case. | |
3566 | */ | |
3567 | default_hstate_idx = hstate_index(size_to_hstate(HPAGE_SIZE)); | |
3568 | if (default_hstate_max_huge_pages) { | |
3569 | if (default_hstate.max_huge_pages) { | |
3570 | char buf[32]; | |
3571 | ||
3572 | string_get_size(huge_page_size(&default_hstate), | |
3573 | 1, STRING_UNITS_2, buf, 32); | |
3574 | pr_warn("HugeTLB: Ignoring hugepages=%lu associated with %s page size\n", | |
3575 | default_hstate.max_huge_pages, buf); | |
3576 | pr_warn("HugeTLB: Using hugepages=%lu for number of default huge pages\n", | |
3577 | default_hstate_max_huge_pages); | |
3578 | } | |
3579 | default_hstate.max_huge_pages = | |
3580 | default_hstate_max_huge_pages; | |
d715cf80 | 3581 | } |
f8b74815 | 3582 | } |
a3437870 | 3583 | |
cf11e85f | 3584 | hugetlb_cma_check(); |
a3437870 | 3585 | hugetlb_init_hstates(); |
aa888a74 | 3586 | gather_bootmem_prealloc(); |
a3437870 NA |
3587 | report_hugepages(); |
3588 | ||
3589 | hugetlb_sysfs_init(); | |
9a305230 | 3590 | hugetlb_register_all_nodes(); |
7179e7bf | 3591 | hugetlb_cgroup_file_init(); |
9a305230 | 3592 | |
8382d914 DB |
3593 | #ifdef CONFIG_SMP |
3594 | num_fault_mutexes = roundup_pow_of_two(8 * num_possible_cpus()); | |
3595 | #else | |
3596 | num_fault_mutexes = 1; | |
3597 | #endif | |
c672c7f2 | 3598 | hugetlb_fault_mutex_table = |
6da2ec56 KC |
3599 | kmalloc_array(num_fault_mutexes, sizeof(struct mutex), |
3600 | GFP_KERNEL); | |
c672c7f2 | 3601 | BUG_ON(!hugetlb_fault_mutex_table); |
8382d914 DB |
3602 | |
3603 | for (i = 0; i < num_fault_mutexes; i++) | |
c672c7f2 | 3604 | mutex_init(&hugetlb_fault_mutex_table[i]); |
a3437870 NA |
3605 | return 0; |
3606 | } | |
3e89e1c5 | 3607 | subsys_initcall(hugetlb_init); |
a3437870 | 3608 | |
ae94da89 MK |
3609 | /* Overwritten by architectures with more huge page sizes */ |
3610 | bool __init __attribute((weak)) arch_hugetlb_valid_size(unsigned long size) | |
9fee021d | 3611 | { |
ae94da89 | 3612 | return size == HPAGE_SIZE; |
9fee021d VT |
3613 | } |
3614 | ||
d00181b9 | 3615 | void __init hugetlb_add_hstate(unsigned int order) |
a3437870 NA |
3616 | { |
3617 | struct hstate *h; | |
8faa8b07 AK |
3618 | unsigned long i; |
3619 | ||
a3437870 | 3620 | if (size_to_hstate(PAGE_SIZE << order)) { |
a3437870 NA |
3621 | return; |
3622 | } | |
47d38344 | 3623 | BUG_ON(hugetlb_max_hstate >= HUGE_MAX_HSTATE); |
a3437870 | 3624 | BUG_ON(order == 0); |
47d38344 | 3625 | h = &hstates[hugetlb_max_hstate++]; |
29383967 | 3626 | mutex_init(&h->resize_lock); |
a3437870 | 3627 | h->order = order; |
aca78307 | 3628 | h->mask = ~(huge_page_size(h) - 1); |
8faa8b07 AK |
3629 | for (i = 0; i < MAX_NUMNODES; ++i) |
3630 | INIT_LIST_HEAD(&h->hugepage_freelists[i]); | |
0edaecfa | 3631 | INIT_LIST_HEAD(&h->hugepage_activelist); |
54f18d35 AM |
3632 | h->next_nid_to_alloc = first_memory_node; |
3633 | h->next_nid_to_free = first_memory_node; | |
a3437870 NA |
3634 | snprintf(h->name, HSTATE_NAME_LEN, "hugepages-%lukB", |
3635 | huge_page_size(h)/1024); | |
77490587 | 3636 | hugetlb_vmemmap_init(h); |
8faa8b07 | 3637 | |
a3437870 NA |
3638 | parsed_hstate = h; |
3639 | } | |
3640 | ||
282f4214 MK |
3641 | /* |
3642 | * hugepages command line processing | |
3643 | * hugepages normally follows a valid hugepagsz or default_hugepagsz | |
3644 | * specification. If not, ignore the hugepages value. hugepages can also | |
3645 | * be the first huge page command line option in which case it implicitly | |
3646 | * specifies the number of huge pages for the default size. | |
3647 | */ | |
3648 | static int __init hugepages_setup(char *s) | |
a3437870 NA |
3649 | { |
3650 | unsigned long *mhp; | |
8faa8b07 | 3651 | static unsigned long *last_mhp; |
a3437870 | 3652 | |
9fee021d | 3653 | if (!parsed_valid_hugepagesz) { |
282f4214 | 3654 | pr_warn("HugeTLB: hugepages=%s does not follow a valid hugepagesz, ignoring\n", s); |
9fee021d | 3655 | parsed_valid_hugepagesz = true; |
282f4214 | 3656 | return 0; |
9fee021d | 3657 | } |
282f4214 | 3658 | |
a3437870 | 3659 | /* |
282f4214 MK |
3660 | * !hugetlb_max_hstate means we haven't parsed a hugepagesz= parameter |
3661 | * yet, so this hugepages= parameter goes to the "default hstate". | |
3662 | * Otherwise, it goes with the previously parsed hugepagesz or | |
3663 | * default_hugepagesz. | |
a3437870 | 3664 | */ |
9fee021d | 3665 | else if (!hugetlb_max_hstate) |
a3437870 NA |
3666 | mhp = &default_hstate_max_huge_pages; |
3667 | else | |
3668 | mhp = &parsed_hstate->max_huge_pages; | |
3669 | ||
8faa8b07 | 3670 | if (mhp == last_mhp) { |
282f4214 MK |
3671 | pr_warn("HugeTLB: hugepages= specified twice without interleaving hugepagesz=, ignoring hugepages=%s\n", s); |
3672 | return 0; | |
8faa8b07 AK |
3673 | } |
3674 | ||
a3437870 NA |
3675 | if (sscanf(s, "%lu", mhp) <= 0) |
3676 | *mhp = 0; | |
3677 | ||
8faa8b07 AK |
3678 | /* |
3679 | * Global state is always initialized later in hugetlb_init. | |
04adbc3f | 3680 | * But we need to allocate gigantic hstates here early to still |
8faa8b07 AK |
3681 | * use the bootmem allocator. |
3682 | */ | |
04adbc3f | 3683 | if (hugetlb_max_hstate && hstate_is_gigantic(parsed_hstate)) |
8faa8b07 AK |
3684 | hugetlb_hstate_alloc_pages(parsed_hstate); |
3685 | ||
3686 | last_mhp = mhp; | |
3687 | ||
a3437870 NA |
3688 | return 1; |
3689 | } | |
282f4214 | 3690 | __setup("hugepages=", hugepages_setup); |
e11bfbfc | 3691 | |
282f4214 MK |
3692 | /* |
3693 | * hugepagesz command line processing | |
3694 | * A specific huge page size can only be specified once with hugepagesz. | |
3695 | * hugepagesz is followed by hugepages on the command line. The global | |
3696 | * variable 'parsed_valid_hugepagesz' is used to determine if prior | |
3697 | * hugepagesz argument was valid. | |
3698 | */ | |
359f2544 | 3699 | static int __init hugepagesz_setup(char *s) |
e11bfbfc | 3700 | { |
359f2544 | 3701 | unsigned long size; |
282f4214 MK |
3702 | struct hstate *h; |
3703 | ||
3704 | parsed_valid_hugepagesz = false; | |
359f2544 MK |
3705 | size = (unsigned long)memparse(s, NULL); |
3706 | ||
3707 | if (!arch_hugetlb_valid_size(size)) { | |
282f4214 | 3708 | pr_err("HugeTLB: unsupported hugepagesz=%s\n", s); |
359f2544 MK |
3709 | return 0; |
3710 | } | |
3711 | ||
282f4214 MK |
3712 | h = size_to_hstate(size); |
3713 | if (h) { | |
3714 | /* | |
3715 | * hstate for this size already exists. This is normally | |
3716 | * an error, but is allowed if the existing hstate is the | |
3717 | * default hstate. More specifically, it is only allowed if | |
3718 | * the number of huge pages for the default hstate was not | |
3719 | * previously specified. | |
3720 | */ | |
3721 | if (!parsed_default_hugepagesz || h != &default_hstate || | |
3722 | default_hstate.max_huge_pages) { | |
3723 | pr_warn("HugeTLB: hugepagesz=%s specified twice, ignoring\n", s); | |
3724 | return 0; | |
3725 | } | |
3726 | ||
3727 | /* | |
3728 | * No need to call hugetlb_add_hstate() as hstate already | |
3729 | * exists. But, do set parsed_hstate so that a following | |
3730 | * hugepages= parameter will be applied to this hstate. | |
3731 | */ | |
3732 | parsed_hstate = h; | |
3733 | parsed_valid_hugepagesz = true; | |
3734 | return 1; | |
38237830 MK |
3735 | } |
3736 | ||
359f2544 | 3737 | hugetlb_add_hstate(ilog2(size) - PAGE_SHIFT); |
282f4214 | 3738 | parsed_valid_hugepagesz = true; |
e11bfbfc NP |
3739 | return 1; |
3740 | } | |
359f2544 MK |
3741 | __setup("hugepagesz=", hugepagesz_setup); |
3742 | ||
282f4214 MK |
3743 | /* |
3744 | * default_hugepagesz command line input | |
3745 | * Only one instance of default_hugepagesz allowed on command line. | |
3746 | */ | |
ae94da89 | 3747 | static int __init default_hugepagesz_setup(char *s) |
e11bfbfc | 3748 | { |
ae94da89 MK |
3749 | unsigned long size; |
3750 | ||
282f4214 | 3751 | parsed_valid_hugepagesz = false; |
282f4214 MK |
3752 | if (parsed_default_hugepagesz) { |
3753 | pr_err("HugeTLB: default_hugepagesz previously specified, ignoring %s\n", s); | |
3754 | return 0; | |
3755 | } | |
3756 | ||
ae94da89 MK |
3757 | size = (unsigned long)memparse(s, NULL); |
3758 | ||
3759 | if (!arch_hugetlb_valid_size(size)) { | |
282f4214 | 3760 | pr_err("HugeTLB: unsupported default_hugepagesz=%s\n", s); |
ae94da89 MK |
3761 | return 0; |
3762 | } | |
3763 | ||
282f4214 MK |
3764 | hugetlb_add_hstate(ilog2(size) - PAGE_SHIFT); |
3765 | parsed_valid_hugepagesz = true; | |
3766 | parsed_default_hugepagesz = true; | |
3767 | default_hstate_idx = hstate_index(size_to_hstate(size)); | |
3768 | ||
3769 | /* | |
3770 | * The number of default huge pages (for this size) could have been | |
3771 | * specified as the first hugetlb parameter: hugepages=X. If so, | |
3772 | * then default_hstate_max_huge_pages is set. If the default huge | |
3773 | * page size is gigantic (>= MAX_ORDER), then the pages must be | |
3774 | * allocated here from bootmem allocator. | |
3775 | */ | |
3776 | if (default_hstate_max_huge_pages) { | |
3777 | default_hstate.max_huge_pages = default_hstate_max_huge_pages; | |
3778 | if (hstate_is_gigantic(&default_hstate)) | |
3779 | hugetlb_hstate_alloc_pages(&default_hstate); | |
3780 | default_hstate_max_huge_pages = 0; | |
3781 | } | |
3782 | ||
e11bfbfc NP |
3783 | return 1; |
3784 | } | |
ae94da89 | 3785 | __setup("default_hugepagesz=", default_hugepagesz_setup); |
a3437870 | 3786 | |
8ca39e68 | 3787 | static unsigned int allowed_mems_nr(struct hstate *h) |
8a213460 NA |
3788 | { |
3789 | int node; | |
3790 | unsigned int nr = 0; | |
8ca39e68 MS |
3791 | nodemask_t *mpol_allowed; |
3792 | unsigned int *array = h->free_huge_pages_node; | |
3793 | gfp_t gfp_mask = htlb_alloc_mask(h); | |
3794 | ||
3795 | mpol_allowed = policy_nodemask_current(gfp_mask); | |
8a213460 | 3796 | |
8ca39e68 | 3797 | for_each_node_mask(node, cpuset_current_mems_allowed) { |
c93b0a99 | 3798 | if (!mpol_allowed || node_isset(node, *mpol_allowed)) |
8ca39e68 MS |
3799 | nr += array[node]; |
3800 | } | |
8a213460 NA |
3801 | |
3802 | return nr; | |
3803 | } | |
3804 | ||
3805 | #ifdef CONFIG_SYSCTL | |
17743798 MS |
3806 | static int proc_hugetlb_doulongvec_minmax(struct ctl_table *table, int write, |
3807 | void *buffer, size_t *length, | |
3808 | loff_t *ppos, unsigned long *out) | |
3809 | { | |
3810 | struct ctl_table dup_table; | |
3811 | ||
3812 | /* | |
3813 | * In order to avoid races with __do_proc_doulongvec_minmax(), we | |
3814 | * can duplicate the @table and alter the duplicate of it. | |
3815 | */ | |
3816 | dup_table = *table; | |
3817 | dup_table.data = out; | |
3818 | ||
3819 | return proc_doulongvec_minmax(&dup_table, write, buffer, length, ppos); | |
3820 | } | |
3821 | ||
06808b08 LS |
3822 | static int hugetlb_sysctl_handler_common(bool obey_mempolicy, |
3823 | struct ctl_table *table, int write, | |
32927393 | 3824 | void *buffer, size_t *length, loff_t *ppos) |
1da177e4 | 3825 | { |
e5ff2159 | 3826 | struct hstate *h = &default_hstate; |
238d3c13 | 3827 | unsigned long tmp = h->max_huge_pages; |
08d4a246 | 3828 | int ret; |
e5ff2159 | 3829 | |
457c1b27 | 3830 | if (!hugepages_supported()) |
86613628 | 3831 | return -EOPNOTSUPP; |
457c1b27 | 3832 | |
17743798 MS |
3833 | ret = proc_hugetlb_doulongvec_minmax(table, write, buffer, length, ppos, |
3834 | &tmp); | |
08d4a246 MH |
3835 | if (ret) |
3836 | goto out; | |
e5ff2159 | 3837 | |
238d3c13 DR |
3838 | if (write) |
3839 | ret = __nr_hugepages_store_common(obey_mempolicy, h, | |
3840 | NUMA_NO_NODE, tmp, *length); | |
08d4a246 MH |
3841 | out: |
3842 | return ret; | |
1da177e4 | 3843 | } |
396faf03 | 3844 | |
06808b08 | 3845 | int hugetlb_sysctl_handler(struct ctl_table *table, int write, |
32927393 | 3846 | void *buffer, size_t *length, loff_t *ppos) |
06808b08 LS |
3847 | { |
3848 | ||
3849 | return hugetlb_sysctl_handler_common(false, table, write, | |
3850 | buffer, length, ppos); | |
3851 | } | |
3852 | ||
3853 | #ifdef CONFIG_NUMA | |
3854 | int hugetlb_mempolicy_sysctl_handler(struct ctl_table *table, int write, | |
32927393 | 3855 | void *buffer, size_t *length, loff_t *ppos) |
06808b08 LS |
3856 | { |
3857 | return hugetlb_sysctl_handler_common(true, table, write, | |
3858 | buffer, length, ppos); | |
3859 | } | |
3860 | #endif /* CONFIG_NUMA */ | |
3861 | ||
a3d0c6aa | 3862 | int hugetlb_overcommit_handler(struct ctl_table *table, int write, |
32927393 | 3863 | void *buffer, size_t *length, loff_t *ppos) |
a3d0c6aa | 3864 | { |
a5516438 | 3865 | struct hstate *h = &default_hstate; |
e5ff2159 | 3866 | unsigned long tmp; |
08d4a246 | 3867 | int ret; |
e5ff2159 | 3868 | |
457c1b27 | 3869 | if (!hugepages_supported()) |
86613628 | 3870 | return -EOPNOTSUPP; |
457c1b27 | 3871 | |
c033a93c | 3872 | tmp = h->nr_overcommit_huge_pages; |
e5ff2159 | 3873 | |
bae7f4ae | 3874 | if (write && hstate_is_gigantic(h)) |
adbe8726 EM |
3875 | return -EINVAL; |
3876 | ||
17743798 MS |
3877 | ret = proc_hugetlb_doulongvec_minmax(table, write, buffer, length, ppos, |
3878 | &tmp); | |
08d4a246 MH |
3879 | if (ret) |
3880 | goto out; | |
e5ff2159 AK |
3881 | |
3882 | if (write) { | |
db71ef79 | 3883 | spin_lock_irq(&hugetlb_lock); |
e5ff2159 | 3884 | h->nr_overcommit_huge_pages = tmp; |
db71ef79 | 3885 | spin_unlock_irq(&hugetlb_lock); |
e5ff2159 | 3886 | } |
08d4a246 MH |
3887 | out: |
3888 | return ret; | |
a3d0c6aa NA |
3889 | } |
3890 | ||
1da177e4 LT |
3891 | #endif /* CONFIG_SYSCTL */ |
3892 | ||
e1759c21 | 3893 | void hugetlb_report_meminfo(struct seq_file *m) |
1da177e4 | 3894 | { |
fcb2b0c5 RG |
3895 | struct hstate *h; |
3896 | unsigned long total = 0; | |
3897 | ||
457c1b27 NA |
3898 | if (!hugepages_supported()) |
3899 | return; | |
fcb2b0c5 RG |
3900 | |
3901 | for_each_hstate(h) { | |
3902 | unsigned long count = h->nr_huge_pages; | |
3903 | ||
aca78307 | 3904 | total += huge_page_size(h) * count; |
fcb2b0c5 RG |
3905 | |
3906 | if (h == &default_hstate) | |
3907 | seq_printf(m, | |
3908 | "HugePages_Total: %5lu\n" | |
3909 | "HugePages_Free: %5lu\n" | |
3910 | "HugePages_Rsvd: %5lu\n" | |
3911 | "HugePages_Surp: %5lu\n" | |
3912 | "Hugepagesize: %8lu kB\n", | |
3913 | count, | |
3914 | h->free_huge_pages, | |
3915 | h->resv_huge_pages, | |
3916 | h->surplus_huge_pages, | |
aca78307 | 3917 | huge_page_size(h) / SZ_1K); |
fcb2b0c5 RG |
3918 | } |
3919 | ||
aca78307 | 3920 | seq_printf(m, "Hugetlb: %8lu kB\n", total / SZ_1K); |
1da177e4 LT |
3921 | } |
3922 | ||
7981593b | 3923 | int hugetlb_report_node_meminfo(char *buf, int len, int nid) |
1da177e4 | 3924 | { |
a5516438 | 3925 | struct hstate *h = &default_hstate; |
7981593b | 3926 | |
457c1b27 NA |
3927 | if (!hugepages_supported()) |
3928 | return 0; | |
7981593b JP |
3929 | |
3930 | return sysfs_emit_at(buf, len, | |
3931 | "Node %d HugePages_Total: %5u\n" | |
3932 | "Node %d HugePages_Free: %5u\n" | |
3933 | "Node %d HugePages_Surp: %5u\n", | |
3934 | nid, h->nr_huge_pages_node[nid], | |
3935 | nid, h->free_huge_pages_node[nid], | |
3936 | nid, h->surplus_huge_pages_node[nid]); | |
1da177e4 LT |
3937 | } |
3938 | ||
949f7ec5 DR |
3939 | void hugetlb_show_meminfo(void) |
3940 | { | |
3941 | struct hstate *h; | |
3942 | int nid; | |
3943 | ||
457c1b27 NA |
3944 | if (!hugepages_supported()) |
3945 | return; | |
3946 | ||
949f7ec5 DR |
3947 | for_each_node_state(nid, N_MEMORY) |
3948 | for_each_hstate(h) | |
3949 | pr_info("Node %d hugepages_total=%u hugepages_free=%u hugepages_surp=%u hugepages_size=%lukB\n", | |
3950 | nid, | |
3951 | h->nr_huge_pages_node[nid], | |
3952 | h->free_huge_pages_node[nid], | |
3953 | h->surplus_huge_pages_node[nid], | |
aca78307 | 3954 | huge_page_size(h) / SZ_1K); |
949f7ec5 DR |
3955 | } |
3956 | ||
5d317b2b NH |
3957 | void hugetlb_report_usage(struct seq_file *m, struct mm_struct *mm) |
3958 | { | |
3959 | seq_printf(m, "HugetlbPages:\t%8lu kB\n", | |
3960 | atomic_long_read(&mm->hugetlb_usage) << (PAGE_SHIFT - 10)); | |
3961 | } | |
3962 | ||
1da177e4 LT |
3963 | /* Return the number pages of memory we physically have, in PAGE_SIZE units. */ |
3964 | unsigned long hugetlb_total_pages(void) | |
3965 | { | |
d0028588 WL |
3966 | struct hstate *h; |
3967 | unsigned long nr_total_pages = 0; | |
3968 | ||
3969 | for_each_hstate(h) | |
3970 | nr_total_pages += h->nr_huge_pages * pages_per_huge_page(h); | |
3971 | return nr_total_pages; | |
1da177e4 | 3972 | } |
1da177e4 | 3973 | |
a5516438 | 3974 | static int hugetlb_acct_memory(struct hstate *h, long delta) |
fc1b8a73 MG |
3975 | { |
3976 | int ret = -ENOMEM; | |
3977 | ||
0aa7f354 ML |
3978 | if (!delta) |
3979 | return 0; | |
3980 | ||
db71ef79 | 3981 | spin_lock_irq(&hugetlb_lock); |
fc1b8a73 MG |
3982 | /* |
3983 | * When cpuset is configured, it breaks the strict hugetlb page | |
3984 | * reservation as the accounting is done on a global variable. Such | |
3985 | * reservation is completely rubbish in the presence of cpuset because | |
3986 | * the reservation is not checked against page availability for the | |
3987 | * current cpuset. Application can still potentially OOM'ed by kernel | |
3988 | * with lack of free htlb page in cpuset that the task is in. | |
3989 | * Attempt to enforce strict accounting with cpuset is almost | |
3990 | * impossible (or too ugly) because cpuset is too fluid that | |
3991 | * task or memory node can be dynamically moved between cpusets. | |
3992 | * | |
3993 | * The change of semantics for shared hugetlb mapping with cpuset is | |
3994 | * undesirable. However, in order to preserve some of the semantics, | |
3995 | * we fall back to check against current free page availability as | |
3996 | * a best attempt and hopefully to minimize the impact of changing | |
3997 | * semantics that cpuset has. | |
8ca39e68 MS |
3998 | * |
3999 | * Apart from cpuset, we also have memory policy mechanism that | |
4000 | * also determines from which node the kernel will allocate memory | |
4001 | * in a NUMA system. So similar to cpuset, we also should consider | |
4002 | * the memory policy of the current task. Similar to the description | |
4003 | * above. | |
fc1b8a73 MG |
4004 | */ |
4005 | if (delta > 0) { | |
a5516438 | 4006 | if (gather_surplus_pages(h, delta) < 0) |
fc1b8a73 MG |
4007 | goto out; |
4008 | ||
8ca39e68 | 4009 | if (delta > allowed_mems_nr(h)) { |
a5516438 | 4010 | return_unused_surplus_pages(h, delta); |
fc1b8a73 MG |
4011 | goto out; |
4012 | } | |
4013 | } | |
4014 | ||
4015 | ret = 0; | |
4016 | if (delta < 0) | |
a5516438 | 4017 | return_unused_surplus_pages(h, (unsigned long) -delta); |
fc1b8a73 MG |
4018 | |
4019 | out: | |
db71ef79 | 4020 | spin_unlock_irq(&hugetlb_lock); |
fc1b8a73 MG |
4021 | return ret; |
4022 | } | |
4023 | ||
84afd99b AW |
4024 | static void hugetlb_vm_op_open(struct vm_area_struct *vma) |
4025 | { | |
f522c3ac | 4026 | struct resv_map *resv = vma_resv_map(vma); |
84afd99b AW |
4027 | |
4028 | /* | |
4029 | * This new VMA should share its siblings reservation map if present. | |
4030 | * The VMA will only ever have a valid reservation map pointer where | |
4031 | * it is being copied for another still existing VMA. As that VMA | |
25985edc | 4032 | * has a reference to the reservation map it cannot disappear until |
84afd99b AW |
4033 | * after this open call completes. It is therefore safe to take a |
4034 | * new reference here without additional locking. | |
4035 | */ | |
4e35f483 | 4036 | if (resv && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) |
f522c3ac | 4037 | kref_get(&resv->refs); |
84afd99b AW |
4038 | } |
4039 | ||
a1e78772 MG |
4040 | static void hugetlb_vm_op_close(struct vm_area_struct *vma) |
4041 | { | |
a5516438 | 4042 | struct hstate *h = hstate_vma(vma); |
f522c3ac | 4043 | struct resv_map *resv = vma_resv_map(vma); |
90481622 | 4044 | struct hugepage_subpool *spool = subpool_vma(vma); |
4e35f483 | 4045 | unsigned long reserve, start, end; |
1c5ecae3 | 4046 | long gbl_reserve; |
84afd99b | 4047 | |
4e35f483 JK |
4048 | if (!resv || !is_vma_resv_set(vma, HPAGE_RESV_OWNER)) |
4049 | return; | |
84afd99b | 4050 | |
4e35f483 JK |
4051 | start = vma_hugecache_offset(h, vma, vma->vm_start); |
4052 | end = vma_hugecache_offset(h, vma, vma->vm_end); | |
84afd99b | 4053 | |
4e35f483 | 4054 | reserve = (end - start) - region_count(resv, start, end); |
e9fe92ae | 4055 | hugetlb_cgroup_uncharge_counter(resv, start, end); |
4e35f483 | 4056 | if (reserve) { |
1c5ecae3 MK |
4057 | /* |
4058 | * Decrement reserve counts. The global reserve count may be | |
4059 | * adjusted if the subpool has a minimum size. | |
4060 | */ | |
4061 | gbl_reserve = hugepage_subpool_put_pages(spool, reserve); | |
4062 | hugetlb_acct_memory(h, -gbl_reserve); | |
84afd99b | 4063 | } |
e9fe92ae MA |
4064 | |
4065 | kref_put(&resv->refs, resv_map_release); | |
a1e78772 MG |
4066 | } |
4067 | ||
31383c68 DW |
4068 | static int hugetlb_vm_op_split(struct vm_area_struct *vma, unsigned long addr) |
4069 | { | |
4070 | if (addr & ~(huge_page_mask(hstate_vma(vma)))) | |
4071 | return -EINVAL; | |
4072 | return 0; | |
4073 | } | |
4074 | ||
05ea8860 DW |
4075 | static unsigned long hugetlb_vm_op_pagesize(struct vm_area_struct *vma) |
4076 | { | |
aca78307 | 4077 | return huge_page_size(hstate_vma(vma)); |
05ea8860 DW |
4078 | } |
4079 | ||
1da177e4 LT |
4080 | /* |
4081 | * We cannot handle pagefaults against hugetlb pages at all. They cause | |
4082 | * handle_mm_fault() to try to instantiate regular-sized pages in the | |
6c26d310 | 4083 | * hugepage VMA. do_page_fault() is supposed to trap this, so BUG is we get |
1da177e4 LT |
4084 | * this far. |
4085 | */ | |
b3ec9f33 | 4086 | static vm_fault_t hugetlb_vm_op_fault(struct vm_fault *vmf) |
1da177e4 LT |
4087 | { |
4088 | BUG(); | |
d0217ac0 | 4089 | return 0; |
1da177e4 LT |
4090 | } |
4091 | ||
eec3636a JC |
4092 | /* |
4093 | * When a new function is introduced to vm_operations_struct and added | |
4094 | * to hugetlb_vm_ops, please consider adding the function to shm_vm_ops. | |
4095 | * This is because under System V memory model, mappings created via | |
4096 | * shmget/shmat with "huge page" specified are backed by hugetlbfs files, | |
4097 | * their original vm_ops are overwritten with shm_vm_ops. | |
4098 | */ | |
f0f37e2f | 4099 | const struct vm_operations_struct hugetlb_vm_ops = { |
d0217ac0 | 4100 | .fault = hugetlb_vm_op_fault, |
84afd99b | 4101 | .open = hugetlb_vm_op_open, |
a1e78772 | 4102 | .close = hugetlb_vm_op_close, |
dd3b614f | 4103 | .may_split = hugetlb_vm_op_split, |
05ea8860 | 4104 | .pagesize = hugetlb_vm_op_pagesize, |
1da177e4 LT |
4105 | }; |
4106 | ||
1e8f889b DG |
4107 | static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page, |
4108 | int writable) | |
63551ae0 DG |
4109 | { |
4110 | pte_t entry; | |
79c1c594 | 4111 | unsigned int shift = huge_page_shift(hstate_vma(vma)); |
63551ae0 | 4112 | |
1e8f889b | 4113 | if (writable) { |
106c992a GS |
4114 | entry = huge_pte_mkwrite(huge_pte_mkdirty(mk_huge_pte(page, |
4115 | vma->vm_page_prot))); | |
63551ae0 | 4116 | } else { |
106c992a GS |
4117 | entry = huge_pte_wrprotect(mk_huge_pte(page, |
4118 | vma->vm_page_prot)); | |
63551ae0 DG |
4119 | } |
4120 | entry = pte_mkyoung(entry); | |
4121 | entry = pte_mkhuge(entry); | |
79c1c594 | 4122 | entry = arch_make_huge_pte(entry, shift, vma->vm_flags); |
63551ae0 DG |
4123 | |
4124 | return entry; | |
4125 | } | |
4126 | ||
1e8f889b DG |
4127 | static void set_huge_ptep_writable(struct vm_area_struct *vma, |
4128 | unsigned long address, pte_t *ptep) | |
4129 | { | |
4130 | pte_t entry; | |
4131 | ||
106c992a | 4132 | entry = huge_pte_mkwrite(huge_pte_mkdirty(huge_ptep_get(ptep))); |
32f84528 | 4133 | if (huge_ptep_set_access_flags(vma, address, ptep, entry, 1)) |
4b3073e1 | 4134 | update_mmu_cache(vma, address, ptep); |
1e8f889b DG |
4135 | } |
4136 | ||
d5ed7444 | 4137 | bool is_hugetlb_entry_migration(pte_t pte) |
4a705fef NH |
4138 | { |
4139 | swp_entry_t swp; | |
4140 | ||
4141 | if (huge_pte_none(pte) || pte_present(pte)) | |
d5ed7444 | 4142 | return false; |
4a705fef | 4143 | swp = pte_to_swp_entry(pte); |
d79d176a | 4144 | if (is_migration_entry(swp)) |
d5ed7444 | 4145 | return true; |
4a705fef | 4146 | else |
d5ed7444 | 4147 | return false; |
4a705fef NH |
4148 | } |
4149 | ||
3e5c3600 | 4150 | static bool is_hugetlb_entry_hwpoisoned(pte_t pte) |
4a705fef NH |
4151 | { |
4152 | swp_entry_t swp; | |
4153 | ||
4154 | if (huge_pte_none(pte) || pte_present(pte)) | |
3e5c3600 | 4155 | return false; |
4a705fef | 4156 | swp = pte_to_swp_entry(pte); |
d79d176a | 4157 | if (is_hwpoison_entry(swp)) |
3e5c3600 | 4158 | return true; |
4a705fef | 4159 | else |
3e5c3600 | 4160 | return false; |
4a705fef | 4161 | } |
1e8f889b | 4162 | |
4eae4efa PX |
4163 | static void |
4164 | hugetlb_install_page(struct vm_area_struct *vma, pte_t *ptep, unsigned long addr, | |
4165 | struct page *new_page) | |
4166 | { | |
4167 | __SetPageUptodate(new_page); | |
4168 | set_huge_pte_at(vma->vm_mm, addr, ptep, make_huge_pte(vma, new_page, 1)); | |
4169 | hugepage_add_new_anon_rmap(new_page, vma, addr); | |
4170 | hugetlb_count_add(pages_per_huge_page(hstate_vma(vma)), vma->vm_mm); | |
4171 | ClearHPageRestoreReserve(new_page); | |
4172 | SetHPageMigratable(new_page); | |
4173 | } | |
4174 | ||
63551ae0 DG |
4175 | int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, |
4176 | struct vm_area_struct *vma) | |
4177 | { | |
5e41540c | 4178 | pte_t *src_pte, *dst_pte, entry, dst_entry; |
63551ae0 | 4179 | struct page *ptepage; |
1c59827d | 4180 | unsigned long addr; |
ca6eb14d | 4181 | bool cow = is_cow_mapping(vma->vm_flags); |
a5516438 AK |
4182 | struct hstate *h = hstate_vma(vma); |
4183 | unsigned long sz = huge_page_size(h); | |
4eae4efa | 4184 | unsigned long npages = pages_per_huge_page(h); |
c0d0381a | 4185 | struct address_space *mapping = vma->vm_file->f_mapping; |
ac46d4f3 | 4186 | struct mmu_notifier_range range; |
e8569dd2 | 4187 | int ret = 0; |
1e8f889b | 4188 | |
ac46d4f3 | 4189 | if (cow) { |
7269f999 | 4190 | mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, src, |
6f4f13e8 | 4191 | vma->vm_start, |
ac46d4f3 JG |
4192 | vma->vm_end); |
4193 | mmu_notifier_invalidate_range_start(&range); | |
c0d0381a MK |
4194 | } else { |
4195 | /* | |
4196 | * For shared mappings i_mmap_rwsem must be held to call | |
4197 | * huge_pte_alloc, otherwise the returned ptep could go | |
4198 | * away if part of a shared pmd and another thread calls | |
4199 | * huge_pmd_unshare. | |
4200 | */ | |
4201 | i_mmap_lock_read(mapping); | |
ac46d4f3 | 4202 | } |
e8569dd2 | 4203 | |
a5516438 | 4204 | for (addr = vma->vm_start; addr < vma->vm_end; addr += sz) { |
cb900f41 | 4205 | spinlock_t *src_ptl, *dst_ptl; |
7868a208 | 4206 | src_pte = huge_pte_offset(src, addr, sz); |
c74df32c HD |
4207 | if (!src_pte) |
4208 | continue; | |
aec44e0f | 4209 | dst_pte = huge_pte_alloc(dst, vma, addr, sz); |
e8569dd2 AS |
4210 | if (!dst_pte) { |
4211 | ret = -ENOMEM; | |
4212 | break; | |
4213 | } | |
c5c99429 | 4214 | |
5e41540c MK |
4215 | /* |
4216 | * If the pagetables are shared don't copy or take references. | |
4217 | * dst_pte == src_pte is the common case of src/dest sharing. | |
4218 | * | |
4219 | * However, src could have 'unshared' and dst shares with | |
4220 | * another vma. If dst_pte !none, this implies sharing. | |
4221 | * Check here before taking page table lock, and once again | |
4222 | * after taking the lock below. | |
4223 | */ | |
4224 | dst_entry = huge_ptep_get(dst_pte); | |
4225 | if ((dst_pte == src_pte) || !huge_pte_none(dst_entry)) | |
c5c99429 LW |
4226 | continue; |
4227 | ||
cb900f41 KS |
4228 | dst_ptl = huge_pte_lock(h, dst, dst_pte); |
4229 | src_ptl = huge_pte_lockptr(h, src, src_pte); | |
4230 | spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING); | |
4a705fef | 4231 | entry = huge_ptep_get(src_pte); |
5e41540c | 4232 | dst_entry = huge_ptep_get(dst_pte); |
4eae4efa | 4233 | again: |
5e41540c MK |
4234 | if (huge_pte_none(entry) || !huge_pte_none(dst_entry)) { |
4235 | /* | |
4236 | * Skip if src entry none. Also, skip in the | |
4237 | * unlikely case dst entry !none as this implies | |
4238 | * sharing with another vma. | |
4239 | */ | |
4a705fef NH |
4240 | ; |
4241 | } else if (unlikely(is_hugetlb_entry_migration(entry) || | |
4242 | is_hugetlb_entry_hwpoisoned(entry))) { | |
4243 | swp_entry_t swp_entry = pte_to_swp_entry(entry); | |
4244 | ||
4dd845b5 | 4245 | if (is_writable_migration_entry(swp_entry) && cow) { |
4a705fef NH |
4246 | /* |
4247 | * COW mappings require pages in both | |
4248 | * parent and child to be set to read. | |
4249 | */ | |
4dd845b5 AP |
4250 | swp_entry = make_readable_migration_entry( |
4251 | swp_offset(swp_entry)); | |
4a705fef | 4252 | entry = swp_entry_to_pte(swp_entry); |
e5251fd4 PA |
4253 | set_huge_swap_pte_at(src, addr, src_pte, |
4254 | entry, sz); | |
4a705fef | 4255 | } |
e5251fd4 | 4256 | set_huge_swap_pte_at(dst, addr, dst_pte, entry, sz); |
4a705fef | 4257 | } else { |
4eae4efa PX |
4258 | entry = huge_ptep_get(src_pte); |
4259 | ptepage = pte_page(entry); | |
4260 | get_page(ptepage); | |
4261 | ||
4262 | /* | |
4263 | * This is a rare case where we see pinned hugetlb | |
4264 | * pages while they're prone to COW. We need to do the | |
4265 | * COW earlier during fork. | |
4266 | * | |
4267 | * When pre-allocating the page or copying data, we | |
4268 | * need to be without the pgtable locks since we could | |
4269 | * sleep during the process. | |
4270 | */ | |
4271 | if (unlikely(page_needs_cow_for_dma(vma, ptepage))) { | |
4272 | pte_t src_pte_old = entry; | |
4273 | struct page *new; | |
4274 | ||
4275 | spin_unlock(src_ptl); | |
4276 | spin_unlock(dst_ptl); | |
4277 | /* Do not use reserve as it's private owned */ | |
4278 | new = alloc_huge_page(vma, addr, 1); | |
4279 | if (IS_ERR(new)) { | |
4280 | put_page(ptepage); | |
4281 | ret = PTR_ERR(new); | |
4282 | break; | |
4283 | } | |
4284 | copy_user_huge_page(new, ptepage, addr, vma, | |
4285 | npages); | |
4286 | put_page(ptepage); | |
4287 | ||
4288 | /* Install the new huge page if src pte stable */ | |
4289 | dst_ptl = huge_pte_lock(h, dst, dst_pte); | |
4290 | src_ptl = huge_pte_lockptr(h, src, src_pte); | |
4291 | spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING); | |
4292 | entry = huge_ptep_get(src_pte); | |
4293 | if (!pte_same(src_pte_old, entry)) { | |
846be085 MK |
4294 | restore_reserve_on_error(h, vma, addr, |
4295 | new); | |
4eae4efa PX |
4296 | put_page(new); |
4297 | /* dst_entry won't change as in child */ | |
4298 | goto again; | |
4299 | } | |
4300 | hugetlb_install_page(vma, dst_pte, addr, new); | |
4301 | spin_unlock(src_ptl); | |
4302 | spin_unlock(dst_ptl); | |
4303 | continue; | |
4304 | } | |
4305 | ||
34ee645e | 4306 | if (cow) { |
0f10851e JG |
4307 | /* |
4308 | * No need to notify as we are downgrading page | |
4309 | * table protection not changing it to point | |
4310 | * to a new page. | |
4311 | * | |
ad56b738 | 4312 | * See Documentation/vm/mmu_notifier.rst |
0f10851e | 4313 | */ |
7f2e9525 | 4314 | huge_ptep_set_wrprotect(src, addr, src_pte); |
84894e1c | 4315 | entry = huge_pte_wrprotect(entry); |
34ee645e | 4316 | } |
4eae4efa | 4317 | |
53f9263b | 4318 | page_dup_rmap(ptepage, true); |
1c59827d | 4319 | set_huge_pte_at(dst, addr, dst_pte, entry); |
4eae4efa | 4320 | hugetlb_count_add(npages, dst); |
1c59827d | 4321 | } |
cb900f41 KS |
4322 | spin_unlock(src_ptl); |
4323 | spin_unlock(dst_ptl); | |
63551ae0 | 4324 | } |
63551ae0 | 4325 | |
e8569dd2 | 4326 | if (cow) |
ac46d4f3 | 4327 | mmu_notifier_invalidate_range_end(&range); |
c0d0381a MK |
4328 | else |
4329 | i_mmap_unlock_read(mapping); | |
e8569dd2 AS |
4330 | |
4331 | return ret; | |
63551ae0 DG |
4332 | } |
4333 | ||
24669e58 AK |
4334 | void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, |
4335 | unsigned long start, unsigned long end, | |
4336 | struct page *ref_page) | |
63551ae0 DG |
4337 | { |
4338 | struct mm_struct *mm = vma->vm_mm; | |
4339 | unsigned long address; | |
c7546f8f | 4340 | pte_t *ptep; |
63551ae0 | 4341 | pte_t pte; |
cb900f41 | 4342 | spinlock_t *ptl; |
63551ae0 | 4343 | struct page *page; |
a5516438 AK |
4344 | struct hstate *h = hstate_vma(vma); |
4345 | unsigned long sz = huge_page_size(h); | |
ac46d4f3 | 4346 | struct mmu_notifier_range range; |
a5516438 | 4347 | |
63551ae0 | 4348 | WARN_ON(!is_vm_hugetlb_page(vma)); |
a5516438 AK |
4349 | BUG_ON(start & ~huge_page_mask(h)); |
4350 | BUG_ON(end & ~huge_page_mask(h)); | |
63551ae0 | 4351 | |
07e32661 AK |
4352 | /* |
4353 | * This is a hugetlb vma, all the pte entries should point | |
4354 | * to huge page. | |
4355 | */ | |
ed6a7935 | 4356 | tlb_change_page_size(tlb, sz); |
24669e58 | 4357 | tlb_start_vma(tlb, vma); |
dff11abe MK |
4358 | |
4359 | /* | |
4360 | * If sharing possible, alert mmu notifiers of worst case. | |
4361 | */ | |
6f4f13e8 JG |
4362 | mmu_notifier_range_init(&range, MMU_NOTIFY_UNMAP, 0, vma, mm, start, |
4363 | end); | |
ac46d4f3 JG |
4364 | adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end); |
4365 | mmu_notifier_invalidate_range_start(&range); | |
569f48b8 | 4366 | address = start; |
569f48b8 | 4367 | for (; address < end; address += sz) { |
7868a208 | 4368 | ptep = huge_pte_offset(mm, address, sz); |
4c887265 | 4369 | if (!ptep) |
c7546f8f DG |
4370 | continue; |
4371 | ||
cb900f41 | 4372 | ptl = huge_pte_lock(h, mm, ptep); |
34ae204f | 4373 | if (huge_pmd_unshare(mm, vma, &address, ptep)) { |
31d49da5 | 4374 | spin_unlock(ptl); |
dff11abe MK |
4375 | /* |
4376 | * We just unmapped a page of PMDs by clearing a PUD. | |
4377 | * The caller's TLB flush range should cover this area. | |
4378 | */ | |
31d49da5 AK |
4379 | continue; |
4380 | } | |
39dde65c | 4381 | |
6629326b | 4382 | pte = huge_ptep_get(ptep); |
31d49da5 AK |
4383 | if (huge_pte_none(pte)) { |
4384 | spin_unlock(ptl); | |
4385 | continue; | |
4386 | } | |
6629326b HD |
4387 | |
4388 | /* | |
9fbc1f63 NH |
4389 | * Migrating hugepage or HWPoisoned hugepage is already |
4390 | * unmapped and its refcount is dropped, so just clear pte here. | |
6629326b | 4391 | */ |
9fbc1f63 | 4392 | if (unlikely(!pte_present(pte))) { |
9386fac3 | 4393 | huge_pte_clear(mm, address, ptep, sz); |
31d49da5 AK |
4394 | spin_unlock(ptl); |
4395 | continue; | |
8c4894c6 | 4396 | } |
6629326b HD |
4397 | |
4398 | page = pte_page(pte); | |
04f2cbe3 MG |
4399 | /* |
4400 | * If a reference page is supplied, it is because a specific | |
4401 | * page is being unmapped, not a range. Ensure the page we | |
4402 | * are about to unmap is the actual page of interest. | |
4403 | */ | |
4404 | if (ref_page) { | |
31d49da5 AK |
4405 | if (page != ref_page) { |
4406 | spin_unlock(ptl); | |
4407 | continue; | |
4408 | } | |
04f2cbe3 MG |
4409 | /* |
4410 | * Mark the VMA as having unmapped its page so that | |
4411 | * future faults in this VMA will fail rather than | |
4412 | * looking like data was lost | |
4413 | */ | |
4414 | set_vma_resv_flags(vma, HPAGE_RESV_UNMAPPED); | |
4415 | } | |
4416 | ||
c7546f8f | 4417 | pte = huge_ptep_get_and_clear(mm, address, ptep); |
b528e4b6 | 4418 | tlb_remove_huge_tlb_entry(h, tlb, ptep, address); |
106c992a | 4419 | if (huge_pte_dirty(pte)) |
6649a386 | 4420 | set_page_dirty(page); |
9e81130b | 4421 | |
5d317b2b | 4422 | hugetlb_count_sub(pages_per_huge_page(h), mm); |
d281ee61 | 4423 | page_remove_rmap(page, true); |
31d49da5 | 4424 | |
cb900f41 | 4425 | spin_unlock(ptl); |
e77b0852 | 4426 | tlb_remove_page_size(tlb, page, huge_page_size(h)); |
31d49da5 AK |
4427 | /* |
4428 | * Bail out after unmapping reference page if supplied | |
4429 | */ | |
4430 | if (ref_page) | |
4431 | break; | |
fe1668ae | 4432 | } |
ac46d4f3 | 4433 | mmu_notifier_invalidate_range_end(&range); |
24669e58 | 4434 | tlb_end_vma(tlb, vma); |
1da177e4 | 4435 | } |
63551ae0 | 4436 | |
d833352a MG |
4437 | void __unmap_hugepage_range_final(struct mmu_gather *tlb, |
4438 | struct vm_area_struct *vma, unsigned long start, | |
4439 | unsigned long end, struct page *ref_page) | |
4440 | { | |
4441 | __unmap_hugepage_range(tlb, vma, start, end, ref_page); | |
4442 | ||
4443 | /* | |
4444 | * Clear this flag so that x86's huge_pmd_share page_table_shareable | |
4445 | * test will fail on a vma being torn down, and not grab a page table | |
4446 | * on its way out. We're lucky that the flag has such an appropriate | |
4447 | * name, and can in fact be safely cleared here. We could clear it | |
4448 | * before the __unmap_hugepage_range above, but all that's necessary | |
c8c06efa | 4449 | * is to clear it before releasing the i_mmap_rwsem. This works |
d833352a | 4450 | * because in the context this is called, the VMA is about to be |
c8c06efa | 4451 | * destroyed and the i_mmap_rwsem is held. |
d833352a MG |
4452 | */ |
4453 | vma->vm_flags &= ~VM_MAYSHARE; | |
4454 | } | |
4455 | ||
502717f4 | 4456 | void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, |
04f2cbe3 | 4457 | unsigned long end, struct page *ref_page) |
502717f4 | 4458 | { |
24669e58 | 4459 | struct mmu_gather tlb; |
dff11abe | 4460 | |
a72afd87 | 4461 | tlb_gather_mmu(&tlb, vma->vm_mm); |
24669e58 | 4462 | __unmap_hugepage_range(&tlb, vma, start, end, ref_page); |
ae8eba8b | 4463 | tlb_finish_mmu(&tlb); |
502717f4 CK |
4464 | } |
4465 | ||
04f2cbe3 MG |
4466 | /* |
4467 | * This is called when the original mapper is failing to COW a MAP_PRIVATE | |
578b7725 | 4468 | * mapping it owns the reserve page for. The intention is to unmap the page |
04f2cbe3 MG |
4469 | * from other VMAs and let the children be SIGKILLed if they are faulting the |
4470 | * same region. | |
4471 | */ | |
2f4612af DB |
4472 | static void unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma, |
4473 | struct page *page, unsigned long address) | |
04f2cbe3 | 4474 | { |
7526674d | 4475 | struct hstate *h = hstate_vma(vma); |
04f2cbe3 MG |
4476 | struct vm_area_struct *iter_vma; |
4477 | struct address_space *mapping; | |
04f2cbe3 MG |
4478 | pgoff_t pgoff; |
4479 | ||
4480 | /* | |
4481 | * vm_pgoff is in PAGE_SIZE units, hence the different calculation | |
4482 | * from page cache lookup which is in HPAGE_SIZE units. | |
4483 | */ | |
7526674d | 4484 | address = address & huge_page_mask(h); |
36e4f20a MH |
4485 | pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) + |
4486 | vma->vm_pgoff; | |
93c76a3d | 4487 | mapping = vma->vm_file->f_mapping; |
04f2cbe3 | 4488 | |
4eb2b1dc MG |
4489 | /* |
4490 | * Take the mapping lock for the duration of the table walk. As | |
4491 | * this mapping should be shared between all the VMAs, | |
4492 | * __unmap_hugepage_range() is called as the lock is already held | |
4493 | */ | |
83cde9e8 | 4494 | i_mmap_lock_write(mapping); |
6b2dbba8 | 4495 | vma_interval_tree_foreach(iter_vma, &mapping->i_mmap, pgoff, pgoff) { |
04f2cbe3 MG |
4496 | /* Do not unmap the current VMA */ |
4497 | if (iter_vma == vma) | |
4498 | continue; | |
4499 | ||
2f84a899 MG |
4500 | /* |
4501 | * Shared VMAs have their own reserves and do not affect | |
4502 | * MAP_PRIVATE accounting but it is possible that a shared | |
4503 | * VMA is using the same page so check and skip such VMAs. | |
4504 | */ | |
4505 | if (iter_vma->vm_flags & VM_MAYSHARE) | |
4506 | continue; | |
4507 | ||
04f2cbe3 MG |
4508 | /* |
4509 | * Unmap the page from other VMAs without their own reserves. | |
4510 | * They get marked to be SIGKILLed if they fault in these | |
4511 | * areas. This is because a future no-page fault on this VMA | |
4512 | * could insert a zeroed page instead of the data existing | |
4513 | * from the time of fork. This would look like data corruption | |
4514 | */ | |
4515 | if (!is_vma_resv_set(iter_vma, HPAGE_RESV_OWNER)) | |
24669e58 AK |
4516 | unmap_hugepage_range(iter_vma, address, |
4517 | address + huge_page_size(h), page); | |
04f2cbe3 | 4518 | } |
83cde9e8 | 4519 | i_mmap_unlock_write(mapping); |
04f2cbe3 MG |
4520 | } |
4521 | ||
0fe6e20b NH |
4522 | /* |
4523 | * Hugetlb_cow() should be called with page lock of the original hugepage held. | |
ef009b25 MH |
4524 | * Called with hugetlb_instantiation_mutex held and pte_page locked so we |
4525 | * cannot race with other handlers or page migration. | |
4526 | * Keep the pte_same checks anyway to make transition from the mutex easier. | |
0fe6e20b | 4527 | */ |
2b740303 | 4528 | static vm_fault_t hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma, |
974e6d66 | 4529 | unsigned long address, pte_t *ptep, |
3999f52e | 4530 | struct page *pagecache_page, spinlock_t *ptl) |
1e8f889b | 4531 | { |
3999f52e | 4532 | pte_t pte; |
a5516438 | 4533 | struct hstate *h = hstate_vma(vma); |
1e8f889b | 4534 | struct page *old_page, *new_page; |
2b740303 SJ |
4535 | int outside_reserve = 0; |
4536 | vm_fault_t ret = 0; | |
974e6d66 | 4537 | unsigned long haddr = address & huge_page_mask(h); |
ac46d4f3 | 4538 | struct mmu_notifier_range range; |
1e8f889b | 4539 | |
3999f52e | 4540 | pte = huge_ptep_get(ptep); |
1e8f889b DG |
4541 | old_page = pte_page(pte); |
4542 | ||
04f2cbe3 | 4543 | retry_avoidcopy: |
1e8f889b DG |
4544 | /* If no-one else is actually using this page, avoid the copy |
4545 | * and just make the page writable */ | |
37a2140d | 4546 | if (page_mapcount(old_page) == 1 && PageAnon(old_page)) { |
5a49973d | 4547 | page_move_anon_rmap(old_page, vma); |
5b7a1d40 | 4548 | set_huge_ptep_writable(vma, haddr, ptep); |
83c54070 | 4549 | return 0; |
1e8f889b DG |
4550 | } |
4551 | ||
04f2cbe3 MG |
4552 | /* |
4553 | * If the process that created a MAP_PRIVATE mapping is about to | |
4554 | * perform a COW due to a shared page count, attempt to satisfy | |
4555 | * the allocation without using the existing reserves. The pagecache | |
4556 | * page is used to determine if the reserve at this address was | |
4557 | * consumed or not. If reserves were used, a partial faulted mapping | |
4558 | * at the time of fork() could consume its reserves on COW instead | |
4559 | * of the full address range. | |
4560 | */ | |
5944d011 | 4561 | if (is_vma_resv_set(vma, HPAGE_RESV_OWNER) && |
04f2cbe3 MG |
4562 | old_page != pagecache_page) |
4563 | outside_reserve = 1; | |
4564 | ||
09cbfeaf | 4565 | get_page(old_page); |
b76c8cfb | 4566 | |
ad4404a2 DB |
4567 | /* |
4568 | * Drop page table lock as buddy allocator may be called. It will | |
4569 | * be acquired again before returning to the caller, as expected. | |
4570 | */ | |
cb900f41 | 4571 | spin_unlock(ptl); |
5b7a1d40 | 4572 | new_page = alloc_huge_page(vma, haddr, outside_reserve); |
1e8f889b | 4573 | |
2fc39cec | 4574 | if (IS_ERR(new_page)) { |
04f2cbe3 MG |
4575 | /* |
4576 | * If a process owning a MAP_PRIVATE mapping fails to COW, | |
4577 | * it is due to references held by a child and an insufficient | |
4578 | * huge page pool. To guarantee the original mappers | |
4579 | * reliability, unmap the page from child processes. The child | |
4580 | * may get SIGKILLed if it later faults. | |
4581 | */ | |
4582 | if (outside_reserve) { | |
e7dd91c4 MK |
4583 | struct address_space *mapping = vma->vm_file->f_mapping; |
4584 | pgoff_t idx; | |
4585 | u32 hash; | |
4586 | ||
09cbfeaf | 4587 | put_page(old_page); |
04f2cbe3 | 4588 | BUG_ON(huge_pte_none(pte)); |
e7dd91c4 MK |
4589 | /* |
4590 | * Drop hugetlb_fault_mutex and i_mmap_rwsem before | |
4591 | * unmapping. unmapping needs to hold i_mmap_rwsem | |
4592 | * in write mode. Dropping i_mmap_rwsem in read mode | |
4593 | * here is OK as COW mappings do not interact with | |
4594 | * PMD sharing. | |
4595 | * | |
4596 | * Reacquire both after unmap operation. | |
4597 | */ | |
4598 | idx = vma_hugecache_offset(h, vma, haddr); | |
4599 | hash = hugetlb_fault_mutex_hash(mapping, idx); | |
4600 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); | |
4601 | i_mmap_unlock_read(mapping); | |
4602 | ||
5b7a1d40 | 4603 | unmap_ref_private(mm, vma, old_page, haddr); |
e7dd91c4 MK |
4604 | |
4605 | i_mmap_lock_read(mapping); | |
4606 | mutex_lock(&hugetlb_fault_mutex_table[hash]); | |
2f4612af | 4607 | spin_lock(ptl); |
5b7a1d40 | 4608 | ptep = huge_pte_offset(mm, haddr, huge_page_size(h)); |
2f4612af DB |
4609 | if (likely(ptep && |
4610 | pte_same(huge_ptep_get(ptep), pte))) | |
4611 | goto retry_avoidcopy; | |
4612 | /* | |
4613 | * race occurs while re-acquiring page table | |
4614 | * lock, and our job is done. | |
4615 | */ | |
4616 | return 0; | |
04f2cbe3 MG |
4617 | } |
4618 | ||
2b740303 | 4619 | ret = vmf_error(PTR_ERR(new_page)); |
ad4404a2 | 4620 | goto out_release_old; |
1e8f889b DG |
4621 | } |
4622 | ||
0fe6e20b NH |
4623 | /* |
4624 | * When the original hugepage is shared one, it does not have | |
4625 | * anon_vma prepared. | |
4626 | */ | |
44e2aa93 | 4627 | if (unlikely(anon_vma_prepare(vma))) { |
ad4404a2 DB |
4628 | ret = VM_FAULT_OOM; |
4629 | goto out_release_all; | |
44e2aa93 | 4630 | } |
0fe6e20b | 4631 | |
974e6d66 | 4632 | copy_user_huge_page(new_page, old_page, address, vma, |
47ad8475 | 4633 | pages_per_huge_page(h)); |
0ed361de | 4634 | __SetPageUptodate(new_page); |
1e8f889b | 4635 | |
7269f999 | 4636 | mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, mm, haddr, |
6f4f13e8 | 4637 | haddr + huge_page_size(h)); |
ac46d4f3 | 4638 | mmu_notifier_invalidate_range_start(&range); |
ad4404a2 | 4639 | |
b76c8cfb | 4640 | /* |
cb900f41 | 4641 | * Retake the page table lock to check for racing updates |
b76c8cfb LW |
4642 | * before the page tables are altered |
4643 | */ | |
cb900f41 | 4644 | spin_lock(ptl); |
5b7a1d40 | 4645 | ptep = huge_pte_offset(mm, haddr, huge_page_size(h)); |
a9af0c5d | 4646 | if (likely(ptep && pte_same(huge_ptep_get(ptep), pte))) { |
d6995da3 | 4647 | ClearHPageRestoreReserve(new_page); |
07443a85 | 4648 | |
1e8f889b | 4649 | /* Break COW */ |
5b7a1d40 | 4650 | huge_ptep_clear_flush(vma, haddr, ptep); |
ac46d4f3 | 4651 | mmu_notifier_invalidate_range(mm, range.start, range.end); |
5b7a1d40 | 4652 | set_huge_pte_at(mm, haddr, ptep, |
1e8f889b | 4653 | make_huge_pte(vma, new_page, 1)); |
d281ee61 | 4654 | page_remove_rmap(old_page, true); |
5b7a1d40 | 4655 | hugepage_add_new_anon_rmap(new_page, vma, haddr); |
8f251a3d | 4656 | SetHPageMigratable(new_page); |
1e8f889b DG |
4657 | /* Make the old page be freed below */ |
4658 | new_page = old_page; | |
4659 | } | |
cb900f41 | 4660 | spin_unlock(ptl); |
ac46d4f3 | 4661 | mmu_notifier_invalidate_range_end(&range); |
ad4404a2 | 4662 | out_release_all: |
5b7a1d40 | 4663 | restore_reserve_on_error(h, vma, haddr, new_page); |
09cbfeaf | 4664 | put_page(new_page); |
ad4404a2 | 4665 | out_release_old: |
09cbfeaf | 4666 | put_page(old_page); |
8312034f | 4667 | |
ad4404a2 DB |
4668 | spin_lock(ptl); /* Caller expects lock to be held */ |
4669 | return ret; | |
1e8f889b DG |
4670 | } |
4671 | ||
04f2cbe3 | 4672 | /* Return the pagecache page at a given address within a VMA */ |
a5516438 AK |
4673 | static struct page *hugetlbfs_pagecache_page(struct hstate *h, |
4674 | struct vm_area_struct *vma, unsigned long address) | |
04f2cbe3 MG |
4675 | { |
4676 | struct address_space *mapping; | |
e7c4b0bf | 4677 | pgoff_t idx; |
04f2cbe3 MG |
4678 | |
4679 | mapping = vma->vm_file->f_mapping; | |
a5516438 | 4680 | idx = vma_hugecache_offset(h, vma, address); |
04f2cbe3 MG |
4681 | |
4682 | return find_lock_page(mapping, idx); | |
4683 | } | |
4684 | ||
3ae77f43 HD |
4685 | /* |
4686 | * Return whether there is a pagecache page to back given address within VMA. | |
4687 | * Caller follow_hugetlb_page() holds page_table_lock so we cannot lock_page. | |
4688 | */ | |
4689 | static bool hugetlbfs_pagecache_present(struct hstate *h, | |
2a15efc9 HD |
4690 | struct vm_area_struct *vma, unsigned long address) |
4691 | { | |
4692 | struct address_space *mapping; | |
4693 | pgoff_t idx; | |
4694 | struct page *page; | |
4695 | ||
4696 | mapping = vma->vm_file->f_mapping; | |
4697 | idx = vma_hugecache_offset(h, vma, address); | |
4698 | ||
4699 | page = find_get_page(mapping, idx); | |
4700 | if (page) | |
4701 | put_page(page); | |
4702 | return page != NULL; | |
4703 | } | |
4704 | ||
ab76ad54 MK |
4705 | int huge_add_to_page_cache(struct page *page, struct address_space *mapping, |
4706 | pgoff_t idx) | |
4707 | { | |
4708 | struct inode *inode = mapping->host; | |
4709 | struct hstate *h = hstate_inode(inode); | |
4710 | int err = add_to_page_cache(page, mapping, idx, GFP_KERNEL); | |
4711 | ||
4712 | if (err) | |
4713 | return err; | |
d6995da3 | 4714 | ClearHPageRestoreReserve(page); |
ab76ad54 | 4715 | |
22146c3c MK |
4716 | /* |
4717 | * set page dirty so that it will not be removed from cache/file | |
4718 | * by non-hugetlbfs specific code paths. | |
4719 | */ | |
4720 | set_page_dirty(page); | |
4721 | ||
ab76ad54 MK |
4722 | spin_lock(&inode->i_lock); |
4723 | inode->i_blocks += blocks_per_huge_page(h); | |
4724 | spin_unlock(&inode->i_lock); | |
4725 | return 0; | |
4726 | } | |
4727 | ||
7677f7fd AR |
4728 | static inline vm_fault_t hugetlb_handle_userfault(struct vm_area_struct *vma, |
4729 | struct address_space *mapping, | |
4730 | pgoff_t idx, | |
4731 | unsigned int flags, | |
4732 | unsigned long haddr, | |
4733 | unsigned long reason) | |
4734 | { | |
4735 | vm_fault_t ret; | |
4736 | u32 hash; | |
4737 | struct vm_fault vmf = { | |
4738 | .vma = vma, | |
4739 | .address = haddr, | |
4740 | .flags = flags, | |
4741 | ||
4742 | /* | |
4743 | * Hard to debug if it ends up being | |
4744 | * used by a callee that assumes | |
4745 | * something about the other | |
4746 | * uninitialized fields... same as in | |
4747 | * memory.c | |
4748 | */ | |
4749 | }; | |
4750 | ||
4751 | /* | |
4752 | * hugetlb_fault_mutex and i_mmap_rwsem must be | |
4753 | * dropped before handling userfault. Reacquire | |
4754 | * after handling fault to make calling code simpler. | |
4755 | */ | |
4756 | hash = hugetlb_fault_mutex_hash(mapping, idx); | |
4757 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); | |
4758 | i_mmap_unlock_read(mapping); | |
4759 | ret = handle_userfault(&vmf, reason); | |
4760 | i_mmap_lock_read(mapping); | |
4761 | mutex_lock(&hugetlb_fault_mutex_table[hash]); | |
4762 | ||
4763 | return ret; | |
4764 | } | |
4765 | ||
2b740303 SJ |
4766 | static vm_fault_t hugetlb_no_page(struct mm_struct *mm, |
4767 | struct vm_area_struct *vma, | |
4768 | struct address_space *mapping, pgoff_t idx, | |
4769 | unsigned long address, pte_t *ptep, unsigned int flags) | |
ac9b9c66 | 4770 | { |
a5516438 | 4771 | struct hstate *h = hstate_vma(vma); |
2b740303 | 4772 | vm_fault_t ret = VM_FAULT_SIGBUS; |
409eb8c2 | 4773 | int anon_rmap = 0; |
4c887265 | 4774 | unsigned long size; |
4c887265 | 4775 | struct page *page; |
1e8f889b | 4776 | pte_t new_pte; |
cb900f41 | 4777 | spinlock_t *ptl; |
285b8dca | 4778 | unsigned long haddr = address & huge_page_mask(h); |
cb6acd01 | 4779 | bool new_page = false; |
4c887265 | 4780 | |
04f2cbe3 MG |
4781 | /* |
4782 | * Currently, we are forced to kill the process in the event the | |
4783 | * original mapper has unmapped pages from the child due to a failed | |
25985edc | 4784 | * COW. Warn that such a situation has occurred as it may not be obvious |
04f2cbe3 MG |
4785 | */ |
4786 | if (is_vma_resv_set(vma, HPAGE_RESV_UNMAPPED)) { | |
910154d5 | 4787 | pr_warn_ratelimited("PID %d killed due to inadequate hugepage pool\n", |
ffb22af5 | 4788 | current->pid); |
04f2cbe3 MG |
4789 | return ret; |
4790 | } | |
4791 | ||
4c887265 | 4792 | /* |
87bf91d3 MK |
4793 | * We can not race with truncation due to holding i_mmap_rwsem. |
4794 | * i_size is modified when holding i_mmap_rwsem, so check here | |
4795 | * once for faults beyond end of file. | |
4c887265 | 4796 | */ |
87bf91d3 MK |
4797 | size = i_size_read(mapping->host) >> huge_page_shift(h); |
4798 | if (idx >= size) | |
4799 | goto out; | |
4800 | ||
6bda666a CL |
4801 | retry: |
4802 | page = find_lock_page(mapping, idx); | |
4803 | if (!page) { | |
7677f7fd | 4804 | /* Check for page in userfault range */ |
1a1aad8a | 4805 | if (userfaultfd_missing(vma)) { |
7677f7fd AR |
4806 | ret = hugetlb_handle_userfault(vma, mapping, idx, |
4807 | flags, haddr, | |
4808 | VM_UFFD_MISSING); | |
1a1aad8a MK |
4809 | goto out; |
4810 | } | |
4811 | ||
285b8dca | 4812 | page = alloc_huge_page(vma, haddr, 0); |
2fc39cec | 4813 | if (IS_ERR(page)) { |
4643d67e MK |
4814 | /* |
4815 | * Returning error will result in faulting task being | |
4816 | * sent SIGBUS. The hugetlb fault mutex prevents two | |
4817 | * tasks from racing to fault in the same page which | |
4818 | * could result in false unable to allocate errors. | |
4819 | * Page migration does not take the fault mutex, but | |
4820 | * does a clear then write of pte's under page table | |
4821 | * lock. Page fault code could race with migration, | |
4822 | * notice the clear pte and try to allocate a page | |
4823 | * here. Before returning error, get ptl and make | |
4824 | * sure there really is no pte entry. | |
4825 | */ | |
4826 | ptl = huge_pte_lock(h, mm, ptep); | |
d83e6c8a ML |
4827 | ret = 0; |
4828 | if (huge_pte_none(huge_ptep_get(ptep))) | |
4829 | ret = vmf_error(PTR_ERR(page)); | |
4643d67e | 4830 | spin_unlock(ptl); |
6bda666a CL |
4831 | goto out; |
4832 | } | |
47ad8475 | 4833 | clear_huge_page(page, address, pages_per_huge_page(h)); |
0ed361de | 4834 | __SetPageUptodate(page); |
cb6acd01 | 4835 | new_page = true; |
ac9b9c66 | 4836 | |
f83a275d | 4837 | if (vma->vm_flags & VM_MAYSHARE) { |
ab76ad54 | 4838 | int err = huge_add_to_page_cache(page, mapping, idx); |
6bda666a CL |
4839 | if (err) { |
4840 | put_page(page); | |
6bda666a CL |
4841 | if (err == -EEXIST) |
4842 | goto retry; | |
4843 | goto out; | |
4844 | } | |
23be7468 | 4845 | } else { |
6bda666a | 4846 | lock_page(page); |
0fe6e20b NH |
4847 | if (unlikely(anon_vma_prepare(vma))) { |
4848 | ret = VM_FAULT_OOM; | |
4849 | goto backout_unlocked; | |
4850 | } | |
409eb8c2 | 4851 | anon_rmap = 1; |
23be7468 | 4852 | } |
0fe6e20b | 4853 | } else { |
998b4382 NH |
4854 | /* |
4855 | * If memory error occurs between mmap() and fault, some process | |
4856 | * don't have hwpoisoned swap entry for errored virtual address. | |
4857 | * So we need to block hugepage fault by PG_hwpoison bit check. | |
4858 | */ | |
4859 | if (unlikely(PageHWPoison(page))) { | |
0eb98f15 | 4860 | ret = VM_FAULT_HWPOISON_LARGE | |
972dc4de | 4861 | VM_FAULT_SET_HINDEX(hstate_index(h)); |
998b4382 NH |
4862 | goto backout_unlocked; |
4863 | } | |
7677f7fd AR |
4864 | |
4865 | /* Check for page in userfault range. */ | |
4866 | if (userfaultfd_minor(vma)) { | |
4867 | unlock_page(page); | |
4868 | put_page(page); | |
4869 | ret = hugetlb_handle_userfault(vma, mapping, idx, | |
4870 | flags, haddr, | |
4871 | VM_UFFD_MINOR); | |
4872 | goto out; | |
4873 | } | |
6bda666a | 4874 | } |
1e8f889b | 4875 | |
57303d80 AW |
4876 | /* |
4877 | * If we are going to COW a private mapping later, we examine the | |
4878 | * pending reservations for this page now. This will ensure that | |
4879 | * any allocations necessary to record that reservation occur outside | |
4880 | * the spinlock. | |
4881 | */ | |
5e911373 | 4882 | if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) { |
285b8dca | 4883 | if (vma_needs_reservation(h, vma, haddr) < 0) { |
2b26736c AW |
4884 | ret = VM_FAULT_OOM; |
4885 | goto backout_unlocked; | |
4886 | } | |
5e911373 | 4887 | /* Just decrements count, does not deallocate */ |
285b8dca | 4888 | vma_end_reservation(h, vma, haddr); |
5e911373 | 4889 | } |
57303d80 | 4890 | |
8bea8052 | 4891 | ptl = huge_pte_lock(h, mm, ptep); |
83c54070 | 4892 | ret = 0; |
7f2e9525 | 4893 | if (!huge_pte_none(huge_ptep_get(ptep))) |
4c887265 AL |
4894 | goto backout; |
4895 | ||
07443a85 | 4896 | if (anon_rmap) { |
d6995da3 | 4897 | ClearHPageRestoreReserve(page); |
285b8dca | 4898 | hugepage_add_new_anon_rmap(page, vma, haddr); |
ac714904 | 4899 | } else |
53f9263b | 4900 | page_dup_rmap(page, true); |
1e8f889b DG |
4901 | new_pte = make_huge_pte(vma, page, ((vma->vm_flags & VM_WRITE) |
4902 | && (vma->vm_flags & VM_SHARED))); | |
285b8dca | 4903 | set_huge_pte_at(mm, haddr, ptep, new_pte); |
1e8f889b | 4904 | |
5d317b2b | 4905 | hugetlb_count_add(pages_per_huge_page(h), mm); |
788c7df4 | 4906 | if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) { |
1e8f889b | 4907 | /* Optimization, do the COW without a second fault */ |
974e6d66 | 4908 | ret = hugetlb_cow(mm, vma, address, ptep, page, ptl); |
1e8f889b DG |
4909 | } |
4910 | ||
cb900f41 | 4911 | spin_unlock(ptl); |
cb6acd01 MK |
4912 | |
4913 | /* | |
8f251a3d MK |
4914 | * Only set HPageMigratable in newly allocated pages. Existing pages |
4915 | * found in the pagecache may not have HPageMigratableset if they have | |
4916 | * been isolated for migration. | |
cb6acd01 MK |
4917 | */ |
4918 | if (new_page) | |
8f251a3d | 4919 | SetHPageMigratable(page); |
cb6acd01 | 4920 | |
4c887265 AL |
4921 | unlock_page(page); |
4922 | out: | |
ac9b9c66 | 4923 | return ret; |
4c887265 AL |
4924 | |
4925 | backout: | |
cb900f41 | 4926 | spin_unlock(ptl); |
2b26736c | 4927 | backout_unlocked: |
4c887265 | 4928 | unlock_page(page); |
285b8dca | 4929 | restore_reserve_on_error(h, vma, haddr, page); |
4c887265 AL |
4930 | put_page(page); |
4931 | goto out; | |
ac9b9c66 HD |
4932 | } |
4933 | ||
8382d914 | 4934 | #ifdef CONFIG_SMP |
188b04a7 | 4935 | u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx) |
8382d914 DB |
4936 | { |
4937 | unsigned long key[2]; | |
4938 | u32 hash; | |
4939 | ||
1b426bac MK |
4940 | key[0] = (unsigned long) mapping; |
4941 | key[1] = idx; | |
8382d914 | 4942 | |
55254636 | 4943 | hash = jhash2((u32 *)&key, sizeof(key)/(sizeof(u32)), 0); |
8382d914 DB |
4944 | |
4945 | return hash & (num_fault_mutexes - 1); | |
4946 | } | |
4947 | #else | |
4948 | /* | |
6c26d310 | 4949 | * For uniprocessor systems we always use a single mutex, so just |
8382d914 DB |
4950 | * return 0 and avoid the hashing overhead. |
4951 | */ | |
188b04a7 | 4952 | u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx) |
8382d914 DB |
4953 | { |
4954 | return 0; | |
4955 | } | |
4956 | #endif | |
4957 | ||
2b740303 | 4958 | vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, |
788c7df4 | 4959 | unsigned long address, unsigned int flags) |
86e5216f | 4960 | { |
8382d914 | 4961 | pte_t *ptep, entry; |
cb900f41 | 4962 | spinlock_t *ptl; |
2b740303 | 4963 | vm_fault_t ret; |
8382d914 DB |
4964 | u32 hash; |
4965 | pgoff_t idx; | |
0fe6e20b | 4966 | struct page *page = NULL; |
57303d80 | 4967 | struct page *pagecache_page = NULL; |
a5516438 | 4968 | struct hstate *h = hstate_vma(vma); |
8382d914 | 4969 | struct address_space *mapping; |
0f792cf9 | 4970 | int need_wait_lock = 0; |
285b8dca | 4971 | unsigned long haddr = address & huge_page_mask(h); |
86e5216f | 4972 | |
285b8dca | 4973 | ptep = huge_pte_offset(mm, haddr, huge_page_size(h)); |
fd6a03ed | 4974 | if (ptep) { |
c0d0381a MK |
4975 | /* |
4976 | * Since we hold no locks, ptep could be stale. That is | |
4977 | * OK as we are only making decisions based on content and | |
4978 | * not actually modifying content here. | |
4979 | */ | |
fd6a03ed | 4980 | entry = huge_ptep_get(ptep); |
290408d4 | 4981 | if (unlikely(is_hugetlb_entry_migration(entry))) { |
cb900f41 | 4982 | migration_entry_wait_huge(vma, mm, ptep); |
290408d4 NH |
4983 | return 0; |
4984 | } else if (unlikely(is_hugetlb_entry_hwpoisoned(entry))) | |
32f84528 | 4985 | return VM_FAULT_HWPOISON_LARGE | |
972dc4de | 4986 | VM_FAULT_SET_HINDEX(hstate_index(h)); |
fd6a03ed NH |
4987 | } |
4988 | ||
c0d0381a MK |
4989 | /* |
4990 | * Acquire i_mmap_rwsem before calling huge_pte_alloc and hold | |
87bf91d3 MK |
4991 | * until finished with ptep. This serves two purposes: |
4992 | * 1) It prevents huge_pmd_unshare from being called elsewhere | |
4993 | * and making the ptep no longer valid. | |
4994 | * 2) It synchronizes us with i_size modifications during truncation. | |
c0d0381a MK |
4995 | * |
4996 | * ptep could have already be assigned via huge_pte_offset. That | |
4997 | * is OK, as huge_pte_alloc will return the same value unless | |
4998 | * something has changed. | |
4999 | */ | |
8382d914 | 5000 | mapping = vma->vm_file->f_mapping; |
c0d0381a | 5001 | i_mmap_lock_read(mapping); |
aec44e0f | 5002 | ptep = huge_pte_alloc(mm, vma, haddr, huge_page_size(h)); |
c0d0381a MK |
5003 | if (!ptep) { |
5004 | i_mmap_unlock_read(mapping); | |
5005 | return VM_FAULT_OOM; | |
5006 | } | |
8382d914 | 5007 | |
3935baa9 DG |
5008 | /* |
5009 | * Serialize hugepage allocation and instantiation, so that we don't | |
5010 | * get spurious allocation failures if two CPUs race to instantiate | |
5011 | * the same page in the page cache. | |
5012 | */ | |
c0d0381a | 5013 | idx = vma_hugecache_offset(h, vma, haddr); |
188b04a7 | 5014 | hash = hugetlb_fault_mutex_hash(mapping, idx); |
c672c7f2 | 5015 | mutex_lock(&hugetlb_fault_mutex_table[hash]); |
8382d914 | 5016 | |
7f2e9525 GS |
5017 | entry = huge_ptep_get(ptep); |
5018 | if (huge_pte_none(entry)) { | |
8382d914 | 5019 | ret = hugetlb_no_page(mm, vma, mapping, idx, address, ptep, flags); |
b4d1d99f | 5020 | goto out_mutex; |
3935baa9 | 5021 | } |
86e5216f | 5022 | |
83c54070 | 5023 | ret = 0; |
1e8f889b | 5024 | |
0f792cf9 NH |
5025 | /* |
5026 | * entry could be a migration/hwpoison entry at this point, so this | |
5027 | * check prevents the kernel from going below assuming that we have | |
7c8de358 EP |
5028 | * an active hugepage in pagecache. This goto expects the 2nd page |
5029 | * fault, and is_hugetlb_entry_(migration|hwpoisoned) check will | |
5030 | * properly handle it. | |
0f792cf9 NH |
5031 | */ |
5032 | if (!pte_present(entry)) | |
5033 | goto out_mutex; | |
5034 | ||
57303d80 AW |
5035 | /* |
5036 | * If we are going to COW the mapping later, we examine the pending | |
5037 | * reservations for this page now. This will ensure that any | |
5038 | * allocations necessary to record that reservation occur outside the | |
5039 | * spinlock. For private mappings, we also lookup the pagecache | |
5040 | * page now as it is used to determine if a reservation has been | |
5041 | * consumed. | |
5042 | */ | |
106c992a | 5043 | if ((flags & FAULT_FLAG_WRITE) && !huge_pte_write(entry)) { |
285b8dca | 5044 | if (vma_needs_reservation(h, vma, haddr) < 0) { |
2b26736c | 5045 | ret = VM_FAULT_OOM; |
b4d1d99f | 5046 | goto out_mutex; |
2b26736c | 5047 | } |
5e911373 | 5048 | /* Just decrements count, does not deallocate */ |
285b8dca | 5049 | vma_end_reservation(h, vma, haddr); |
57303d80 | 5050 | |
f83a275d | 5051 | if (!(vma->vm_flags & VM_MAYSHARE)) |
57303d80 | 5052 | pagecache_page = hugetlbfs_pagecache_page(h, |
285b8dca | 5053 | vma, haddr); |
57303d80 AW |
5054 | } |
5055 | ||
0f792cf9 NH |
5056 | ptl = huge_pte_lock(h, mm, ptep); |
5057 | ||
5058 | /* Check for a racing update before calling hugetlb_cow */ | |
5059 | if (unlikely(!pte_same(entry, huge_ptep_get(ptep)))) | |
5060 | goto out_ptl; | |
5061 | ||
56c9cfb1 NH |
5062 | /* |
5063 | * hugetlb_cow() requires page locks of pte_page(entry) and | |
5064 | * pagecache_page, so here we need take the former one | |
5065 | * when page != pagecache_page or !pagecache_page. | |
56c9cfb1 NH |
5066 | */ |
5067 | page = pte_page(entry); | |
5068 | if (page != pagecache_page) | |
0f792cf9 NH |
5069 | if (!trylock_page(page)) { |
5070 | need_wait_lock = 1; | |
5071 | goto out_ptl; | |
5072 | } | |
b4d1d99f | 5073 | |
0f792cf9 | 5074 | get_page(page); |
b4d1d99f | 5075 | |
788c7df4 | 5076 | if (flags & FAULT_FLAG_WRITE) { |
106c992a | 5077 | if (!huge_pte_write(entry)) { |
974e6d66 | 5078 | ret = hugetlb_cow(mm, vma, address, ptep, |
3999f52e | 5079 | pagecache_page, ptl); |
0f792cf9 | 5080 | goto out_put_page; |
b4d1d99f | 5081 | } |
106c992a | 5082 | entry = huge_pte_mkdirty(entry); |
b4d1d99f DG |
5083 | } |
5084 | entry = pte_mkyoung(entry); | |
285b8dca | 5085 | if (huge_ptep_set_access_flags(vma, haddr, ptep, entry, |
788c7df4 | 5086 | flags & FAULT_FLAG_WRITE)) |
285b8dca | 5087 | update_mmu_cache(vma, haddr, ptep); |
0f792cf9 NH |
5088 | out_put_page: |
5089 | if (page != pagecache_page) | |
5090 | unlock_page(page); | |
5091 | put_page(page); | |
cb900f41 KS |
5092 | out_ptl: |
5093 | spin_unlock(ptl); | |
57303d80 AW |
5094 | |
5095 | if (pagecache_page) { | |
5096 | unlock_page(pagecache_page); | |
5097 | put_page(pagecache_page); | |
5098 | } | |
b4d1d99f | 5099 | out_mutex: |
c672c7f2 | 5100 | mutex_unlock(&hugetlb_fault_mutex_table[hash]); |
c0d0381a | 5101 | i_mmap_unlock_read(mapping); |
0f792cf9 NH |
5102 | /* |
5103 | * Generally it's safe to hold refcount during waiting page lock. But | |
5104 | * here we just wait to defer the next page fault to avoid busy loop and | |
5105 | * the page is not used after unlocked before returning from the current | |
5106 | * page fault. So we are safe from accessing freed page, even if we wait | |
5107 | * here without taking refcount. | |
5108 | */ | |
5109 | if (need_wait_lock) | |
5110 | wait_on_page_locked(page); | |
1e8f889b | 5111 | return ret; |
86e5216f AL |
5112 | } |
5113 | ||
714c1891 | 5114 | #ifdef CONFIG_USERFAULTFD |
8fb5debc MK |
5115 | /* |
5116 | * Used by userfaultfd UFFDIO_COPY. Based on mcopy_atomic_pte with | |
5117 | * modifications for huge pages. | |
5118 | */ | |
5119 | int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm, | |
5120 | pte_t *dst_pte, | |
5121 | struct vm_area_struct *dst_vma, | |
5122 | unsigned long dst_addr, | |
5123 | unsigned long src_addr, | |
f6191471 | 5124 | enum mcopy_atomic_mode mode, |
8fb5debc MK |
5125 | struct page **pagep) |
5126 | { | |
f6191471 | 5127 | bool is_continue = (mode == MCOPY_ATOMIC_CONTINUE); |
8cc5fcbb MA |
5128 | struct hstate *h = hstate_vma(dst_vma); |
5129 | struct address_space *mapping = dst_vma->vm_file->f_mapping; | |
5130 | pgoff_t idx = vma_hugecache_offset(h, dst_vma, dst_addr); | |
1e392147 | 5131 | unsigned long size; |
1c9e8def | 5132 | int vm_shared = dst_vma->vm_flags & VM_SHARED; |
8fb5debc MK |
5133 | pte_t _dst_pte; |
5134 | spinlock_t *ptl; | |
8cc5fcbb | 5135 | int ret = -ENOMEM; |
8fb5debc | 5136 | struct page *page; |
f6191471 | 5137 | int writable; |
8fb5debc | 5138 | |
f6191471 AR |
5139 | if (is_continue) { |
5140 | ret = -EFAULT; | |
5141 | page = find_lock_page(mapping, idx); | |
5142 | if (!page) | |
5143 | goto out; | |
5144 | } else if (!*pagep) { | |
d84cf06e MA |
5145 | /* If a page already exists, then it's UFFDIO_COPY for |
5146 | * a non-missing case. Return -EEXIST. | |
5147 | */ | |
5148 | if (vm_shared && | |
5149 | hugetlbfs_pagecache_present(h, dst_vma, dst_addr)) { | |
5150 | ret = -EEXIST; | |
5151 | goto out; | |
5152 | } | |
5153 | ||
8fb5debc | 5154 | page = alloc_huge_page(dst_vma, dst_addr, 0); |
d84cf06e MA |
5155 | if (IS_ERR(page)) { |
5156 | ret = -ENOMEM; | |
8fb5debc | 5157 | goto out; |
d84cf06e | 5158 | } |
8fb5debc MK |
5159 | |
5160 | ret = copy_huge_page_from_user(page, | |
5161 | (const void __user *) src_addr, | |
810a56b9 | 5162 | pages_per_huge_page(h), false); |
8fb5debc | 5163 | |
c1e8d7c6 | 5164 | /* fallback to copy_from_user outside mmap_lock */ |
8fb5debc | 5165 | if (unlikely(ret)) { |
9e368259 | 5166 | ret = -ENOENT; |
8cc5fcbb MA |
5167 | /* Free the allocated page which may have |
5168 | * consumed a reservation. | |
5169 | */ | |
5170 | restore_reserve_on_error(h, dst_vma, dst_addr, page); | |
5171 | put_page(page); | |
5172 | ||
5173 | /* Allocate a temporary page to hold the copied | |
5174 | * contents. | |
5175 | */ | |
5176 | page = alloc_huge_page_vma(h, dst_vma, dst_addr); | |
5177 | if (!page) { | |
5178 | ret = -ENOMEM; | |
5179 | goto out; | |
5180 | } | |
8fb5debc | 5181 | *pagep = page; |
8cc5fcbb MA |
5182 | /* Set the outparam pagep and return to the caller to |
5183 | * copy the contents outside the lock. Don't free the | |
5184 | * page. | |
5185 | */ | |
8fb5debc MK |
5186 | goto out; |
5187 | } | |
5188 | } else { | |
8cc5fcbb MA |
5189 | if (vm_shared && |
5190 | hugetlbfs_pagecache_present(h, dst_vma, dst_addr)) { | |
5191 | put_page(*pagep); | |
5192 | ret = -EEXIST; | |
5193 | *pagep = NULL; | |
5194 | goto out; | |
5195 | } | |
5196 | ||
5197 | page = alloc_huge_page(dst_vma, dst_addr, 0); | |
5198 | if (IS_ERR(page)) { | |
5199 | ret = -ENOMEM; | |
5200 | *pagep = NULL; | |
5201 | goto out; | |
5202 | } | |
5203 | copy_huge_page(page, *pagep); | |
5204 | put_page(*pagep); | |
8fb5debc MK |
5205 | *pagep = NULL; |
5206 | } | |
5207 | ||
5208 | /* | |
5209 | * The memory barrier inside __SetPageUptodate makes sure that | |
5210 | * preceding stores to the page contents become visible before | |
5211 | * the set_pte_at() write. | |
5212 | */ | |
5213 | __SetPageUptodate(page); | |
8fb5debc | 5214 | |
f6191471 AR |
5215 | /* Add shared, newly allocated pages to the page cache. */ |
5216 | if (vm_shared && !is_continue) { | |
1e392147 AA |
5217 | size = i_size_read(mapping->host) >> huge_page_shift(h); |
5218 | ret = -EFAULT; | |
5219 | if (idx >= size) | |
5220 | goto out_release_nounlock; | |
1c9e8def | 5221 | |
1e392147 AA |
5222 | /* |
5223 | * Serialization between remove_inode_hugepages() and | |
5224 | * huge_add_to_page_cache() below happens through the | |
5225 | * hugetlb_fault_mutex_table that here must be hold by | |
5226 | * the caller. | |
5227 | */ | |
1c9e8def MK |
5228 | ret = huge_add_to_page_cache(page, mapping, idx); |
5229 | if (ret) | |
5230 | goto out_release_nounlock; | |
5231 | } | |
5232 | ||
8fb5debc MK |
5233 | ptl = huge_pte_lockptr(h, dst_mm, dst_pte); |
5234 | spin_lock(ptl); | |
5235 | ||
1e392147 AA |
5236 | /* |
5237 | * Recheck the i_size after holding PT lock to make sure not | |
5238 | * to leave any page mapped (as page_mapped()) beyond the end | |
5239 | * of the i_size (remove_inode_hugepages() is strict about | |
5240 | * enforcing that). If we bail out here, we'll also leave a | |
5241 | * page in the radix tree in the vm_shared case beyond the end | |
5242 | * of the i_size, but remove_inode_hugepages() will take care | |
5243 | * of it as soon as we drop the hugetlb_fault_mutex_table. | |
5244 | */ | |
5245 | size = i_size_read(mapping->host) >> huge_page_shift(h); | |
5246 | ret = -EFAULT; | |
5247 | if (idx >= size) | |
5248 | goto out_release_unlock; | |
5249 | ||
8fb5debc MK |
5250 | ret = -EEXIST; |
5251 | if (!huge_pte_none(huge_ptep_get(dst_pte))) | |
5252 | goto out_release_unlock; | |
5253 | ||
1c9e8def MK |
5254 | if (vm_shared) { |
5255 | page_dup_rmap(page, true); | |
5256 | } else { | |
d6995da3 | 5257 | ClearHPageRestoreReserve(page); |
1c9e8def MK |
5258 | hugepage_add_new_anon_rmap(page, dst_vma, dst_addr); |
5259 | } | |
8fb5debc | 5260 | |
f6191471 AR |
5261 | /* For CONTINUE on a non-shared VMA, don't set VM_WRITE for CoW. */ |
5262 | if (is_continue && !vm_shared) | |
5263 | writable = 0; | |
5264 | else | |
5265 | writable = dst_vma->vm_flags & VM_WRITE; | |
5266 | ||
5267 | _dst_pte = make_huge_pte(dst_vma, page, writable); | |
5268 | if (writable) | |
8fb5debc MK |
5269 | _dst_pte = huge_pte_mkdirty(_dst_pte); |
5270 | _dst_pte = pte_mkyoung(_dst_pte); | |
5271 | ||
5272 | set_huge_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte); | |
5273 | ||
5274 | (void)huge_ptep_set_access_flags(dst_vma, dst_addr, dst_pte, _dst_pte, | |
5275 | dst_vma->vm_flags & VM_WRITE); | |
5276 | hugetlb_count_add(pages_per_huge_page(h), dst_mm); | |
5277 | ||
5278 | /* No need to invalidate - it was non-present before */ | |
5279 | update_mmu_cache(dst_vma, dst_addr, dst_pte); | |
5280 | ||
5281 | spin_unlock(ptl); | |
f6191471 AR |
5282 | if (!is_continue) |
5283 | SetHPageMigratable(page); | |
5284 | if (vm_shared || is_continue) | |
1c9e8def | 5285 | unlock_page(page); |
8fb5debc MK |
5286 | ret = 0; |
5287 | out: | |
5288 | return ret; | |
5289 | out_release_unlock: | |
5290 | spin_unlock(ptl); | |
f6191471 | 5291 | if (vm_shared || is_continue) |
1c9e8def | 5292 | unlock_page(page); |
5af10dfd | 5293 | out_release_nounlock: |
846be085 | 5294 | restore_reserve_on_error(h, dst_vma, dst_addr, page); |
8fb5debc MK |
5295 | put_page(page); |
5296 | goto out; | |
5297 | } | |
714c1891 | 5298 | #endif /* CONFIG_USERFAULTFD */ |
8fb5debc | 5299 | |
82e5d378 JM |
5300 | static void record_subpages_vmas(struct page *page, struct vm_area_struct *vma, |
5301 | int refs, struct page **pages, | |
5302 | struct vm_area_struct **vmas) | |
5303 | { | |
5304 | int nr; | |
5305 | ||
5306 | for (nr = 0; nr < refs; nr++) { | |
5307 | if (likely(pages)) | |
5308 | pages[nr] = mem_map_offset(page, nr); | |
5309 | if (vmas) | |
5310 | vmas[nr] = vma; | |
5311 | } | |
5312 | } | |
5313 | ||
28a35716 ML |
5314 | long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, |
5315 | struct page **pages, struct vm_area_struct **vmas, | |
5316 | unsigned long *position, unsigned long *nr_pages, | |
4f6da934 | 5317 | long i, unsigned int flags, int *locked) |
63551ae0 | 5318 | { |
d5d4b0aa CK |
5319 | unsigned long pfn_offset; |
5320 | unsigned long vaddr = *position; | |
28a35716 | 5321 | unsigned long remainder = *nr_pages; |
a5516438 | 5322 | struct hstate *h = hstate_vma(vma); |
0fa5bc40 | 5323 | int err = -EFAULT, refs; |
63551ae0 | 5324 | |
63551ae0 | 5325 | while (vaddr < vma->vm_end && remainder) { |
4c887265 | 5326 | pte_t *pte; |
cb900f41 | 5327 | spinlock_t *ptl = NULL; |
2a15efc9 | 5328 | int absent; |
4c887265 | 5329 | struct page *page; |
63551ae0 | 5330 | |
02057967 DR |
5331 | /* |
5332 | * If we have a pending SIGKILL, don't keep faulting pages and | |
5333 | * potentially allocating memory. | |
5334 | */ | |
fa45f116 | 5335 | if (fatal_signal_pending(current)) { |
02057967 DR |
5336 | remainder = 0; |
5337 | break; | |
5338 | } | |
5339 | ||
4c887265 AL |
5340 | /* |
5341 | * Some archs (sparc64, sh*) have multiple pte_ts to | |
2a15efc9 | 5342 | * each hugepage. We have to make sure we get the |
4c887265 | 5343 | * first, for the page indexing below to work. |
cb900f41 KS |
5344 | * |
5345 | * Note that page table lock is not held when pte is null. | |
4c887265 | 5346 | */ |
7868a208 PA |
5347 | pte = huge_pte_offset(mm, vaddr & huge_page_mask(h), |
5348 | huge_page_size(h)); | |
cb900f41 KS |
5349 | if (pte) |
5350 | ptl = huge_pte_lock(h, mm, pte); | |
2a15efc9 HD |
5351 | absent = !pte || huge_pte_none(huge_ptep_get(pte)); |
5352 | ||
5353 | /* | |
5354 | * When coredumping, it suits get_dump_page if we just return | |
3ae77f43 HD |
5355 | * an error where there's an empty slot with no huge pagecache |
5356 | * to back it. This way, we avoid allocating a hugepage, and | |
5357 | * the sparse dumpfile avoids allocating disk blocks, but its | |
5358 | * huge holes still show up with zeroes where they need to be. | |
2a15efc9 | 5359 | */ |
3ae77f43 HD |
5360 | if (absent && (flags & FOLL_DUMP) && |
5361 | !hugetlbfs_pagecache_present(h, vma, vaddr)) { | |
cb900f41 KS |
5362 | if (pte) |
5363 | spin_unlock(ptl); | |
2a15efc9 HD |
5364 | remainder = 0; |
5365 | break; | |
5366 | } | |
63551ae0 | 5367 | |
9cc3a5bd NH |
5368 | /* |
5369 | * We need call hugetlb_fault for both hugepages under migration | |
5370 | * (in which case hugetlb_fault waits for the migration,) and | |
5371 | * hwpoisoned hugepages (in which case we need to prevent the | |
5372 | * caller from accessing to them.) In order to do this, we use | |
5373 | * here is_swap_pte instead of is_hugetlb_entry_migration and | |
5374 | * is_hugetlb_entry_hwpoisoned. This is because it simply covers | |
5375 | * both cases, and because we can't follow correct pages | |
5376 | * directly from any kind of swap entries. | |
5377 | */ | |
5378 | if (absent || is_swap_pte(huge_ptep_get(pte)) || | |
106c992a GS |
5379 | ((flags & FOLL_WRITE) && |
5380 | !huge_pte_write(huge_ptep_get(pte)))) { | |
2b740303 | 5381 | vm_fault_t ret; |
87ffc118 | 5382 | unsigned int fault_flags = 0; |
63551ae0 | 5383 | |
cb900f41 KS |
5384 | if (pte) |
5385 | spin_unlock(ptl); | |
87ffc118 AA |
5386 | if (flags & FOLL_WRITE) |
5387 | fault_flags |= FAULT_FLAG_WRITE; | |
4f6da934 | 5388 | if (locked) |
71335f37 PX |
5389 | fault_flags |= FAULT_FLAG_ALLOW_RETRY | |
5390 | FAULT_FLAG_KILLABLE; | |
87ffc118 AA |
5391 | if (flags & FOLL_NOWAIT) |
5392 | fault_flags |= FAULT_FLAG_ALLOW_RETRY | | |
5393 | FAULT_FLAG_RETRY_NOWAIT; | |
5394 | if (flags & FOLL_TRIED) { | |
4426e945 PX |
5395 | /* |
5396 | * Note: FAULT_FLAG_ALLOW_RETRY and | |
5397 | * FAULT_FLAG_TRIED can co-exist | |
5398 | */ | |
87ffc118 AA |
5399 | fault_flags |= FAULT_FLAG_TRIED; |
5400 | } | |
5401 | ret = hugetlb_fault(mm, vma, vaddr, fault_flags); | |
5402 | if (ret & VM_FAULT_ERROR) { | |
2be7cfed | 5403 | err = vm_fault_to_errno(ret, flags); |
87ffc118 AA |
5404 | remainder = 0; |
5405 | break; | |
5406 | } | |
5407 | if (ret & VM_FAULT_RETRY) { | |
4f6da934 | 5408 | if (locked && |
1ac25013 | 5409 | !(fault_flags & FAULT_FLAG_RETRY_NOWAIT)) |
4f6da934 | 5410 | *locked = 0; |
87ffc118 AA |
5411 | *nr_pages = 0; |
5412 | /* | |
5413 | * VM_FAULT_RETRY must not return an | |
5414 | * error, it will return zero | |
5415 | * instead. | |
5416 | * | |
5417 | * No need to update "position" as the | |
5418 | * caller will not check it after | |
5419 | * *nr_pages is set to 0. | |
5420 | */ | |
5421 | return i; | |
5422 | } | |
5423 | continue; | |
4c887265 AL |
5424 | } |
5425 | ||
a5516438 | 5426 | pfn_offset = (vaddr & ~huge_page_mask(h)) >> PAGE_SHIFT; |
7f2e9525 | 5427 | page = pte_page(huge_ptep_get(pte)); |
8fde12ca | 5428 | |
acbfb087 ZL |
5429 | /* |
5430 | * If subpage information not requested, update counters | |
5431 | * and skip the same_page loop below. | |
5432 | */ | |
5433 | if (!pages && !vmas && !pfn_offset && | |
5434 | (vaddr + huge_page_size(h) < vma->vm_end) && | |
5435 | (remainder >= pages_per_huge_page(h))) { | |
5436 | vaddr += huge_page_size(h); | |
5437 | remainder -= pages_per_huge_page(h); | |
5438 | i += pages_per_huge_page(h); | |
5439 | spin_unlock(ptl); | |
5440 | continue; | |
5441 | } | |
5442 | ||
82e5d378 JM |
5443 | refs = min3(pages_per_huge_page(h) - pfn_offset, |
5444 | (vma->vm_end - vaddr) >> PAGE_SHIFT, remainder); | |
0fa5bc40 | 5445 | |
82e5d378 JM |
5446 | if (pages || vmas) |
5447 | record_subpages_vmas(mem_map_offset(page, pfn_offset), | |
5448 | vma, refs, | |
5449 | likely(pages) ? pages + i : NULL, | |
5450 | vmas ? vmas + i : NULL); | |
63551ae0 | 5451 | |
82e5d378 | 5452 | if (pages) { |
0fa5bc40 JM |
5453 | /* |
5454 | * try_grab_compound_head() should always succeed here, | |
5455 | * because: a) we hold the ptl lock, and b) we've just | |
5456 | * checked that the huge page is present in the page | |
5457 | * tables. If the huge page is present, then the tail | |
5458 | * pages must also be present. The ptl prevents the | |
5459 | * head page and tail pages from being rearranged in | |
5460 | * any way. So this page must be available at this | |
5461 | * point, unless the page refcount overflowed: | |
5462 | */ | |
82e5d378 | 5463 | if (WARN_ON_ONCE(!try_grab_compound_head(pages[i], |
0fa5bc40 JM |
5464 | refs, |
5465 | flags))) { | |
5466 | spin_unlock(ptl); | |
5467 | remainder = 0; | |
5468 | err = -ENOMEM; | |
5469 | break; | |
5470 | } | |
d5d4b0aa | 5471 | } |
82e5d378 JM |
5472 | |
5473 | vaddr += (refs << PAGE_SHIFT); | |
5474 | remainder -= refs; | |
5475 | i += refs; | |
5476 | ||
cb900f41 | 5477 | spin_unlock(ptl); |
63551ae0 | 5478 | } |
28a35716 | 5479 | *nr_pages = remainder; |
87ffc118 AA |
5480 | /* |
5481 | * setting position is actually required only if remainder is | |
5482 | * not zero but it's faster not to add a "if (remainder)" | |
5483 | * branch. | |
5484 | */ | |
63551ae0 DG |
5485 | *position = vaddr; |
5486 | ||
2be7cfed | 5487 | return i ? i : err; |
63551ae0 | 5488 | } |
8f860591 | 5489 | |
7da4d641 | 5490 | unsigned long hugetlb_change_protection(struct vm_area_struct *vma, |
8f860591 ZY |
5491 | unsigned long address, unsigned long end, pgprot_t newprot) |
5492 | { | |
5493 | struct mm_struct *mm = vma->vm_mm; | |
5494 | unsigned long start = address; | |
5495 | pte_t *ptep; | |
5496 | pte_t pte; | |
a5516438 | 5497 | struct hstate *h = hstate_vma(vma); |
7da4d641 | 5498 | unsigned long pages = 0; |
dff11abe | 5499 | bool shared_pmd = false; |
ac46d4f3 | 5500 | struct mmu_notifier_range range; |
dff11abe MK |
5501 | |
5502 | /* | |
5503 | * In the case of shared PMDs, the area to flush could be beyond | |
ac46d4f3 | 5504 | * start/end. Set range.start/range.end to cover the maximum possible |
dff11abe MK |
5505 | * range if PMD sharing is possible. |
5506 | */ | |
7269f999 JG |
5507 | mmu_notifier_range_init(&range, MMU_NOTIFY_PROTECTION_VMA, |
5508 | 0, vma, mm, start, end); | |
ac46d4f3 | 5509 | adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end); |
8f860591 ZY |
5510 | |
5511 | BUG_ON(address >= end); | |
ac46d4f3 | 5512 | flush_cache_range(vma, range.start, range.end); |
8f860591 | 5513 | |
ac46d4f3 | 5514 | mmu_notifier_invalidate_range_start(&range); |
83cde9e8 | 5515 | i_mmap_lock_write(vma->vm_file->f_mapping); |
a5516438 | 5516 | for (; address < end; address += huge_page_size(h)) { |
cb900f41 | 5517 | spinlock_t *ptl; |
7868a208 | 5518 | ptep = huge_pte_offset(mm, address, huge_page_size(h)); |
8f860591 ZY |
5519 | if (!ptep) |
5520 | continue; | |
cb900f41 | 5521 | ptl = huge_pte_lock(h, mm, ptep); |
34ae204f | 5522 | if (huge_pmd_unshare(mm, vma, &address, ptep)) { |
7da4d641 | 5523 | pages++; |
cb900f41 | 5524 | spin_unlock(ptl); |
dff11abe | 5525 | shared_pmd = true; |
39dde65c | 5526 | continue; |
7da4d641 | 5527 | } |
a8bda28d NH |
5528 | pte = huge_ptep_get(ptep); |
5529 | if (unlikely(is_hugetlb_entry_hwpoisoned(pte))) { | |
5530 | spin_unlock(ptl); | |
5531 | continue; | |
5532 | } | |
5533 | if (unlikely(is_hugetlb_entry_migration(pte))) { | |
5534 | swp_entry_t entry = pte_to_swp_entry(pte); | |
5535 | ||
4dd845b5 | 5536 | if (is_writable_migration_entry(entry)) { |
a8bda28d NH |
5537 | pte_t newpte; |
5538 | ||
4dd845b5 AP |
5539 | entry = make_readable_migration_entry( |
5540 | swp_offset(entry)); | |
a8bda28d | 5541 | newpte = swp_entry_to_pte(entry); |
e5251fd4 PA |
5542 | set_huge_swap_pte_at(mm, address, ptep, |
5543 | newpte, huge_page_size(h)); | |
a8bda28d NH |
5544 | pages++; |
5545 | } | |
5546 | spin_unlock(ptl); | |
5547 | continue; | |
5548 | } | |
5549 | if (!huge_pte_none(pte)) { | |
023bdd00 | 5550 | pte_t old_pte; |
79c1c594 | 5551 | unsigned int shift = huge_page_shift(hstate_vma(vma)); |
023bdd00 AK |
5552 | |
5553 | old_pte = huge_ptep_modify_prot_start(vma, address, ptep); | |
5554 | pte = pte_mkhuge(huge_pte_modify(old_pte, newprot)); | |
79c1c594 | 5555 | pte = arch_make_huge_pte(pte, shift, vma->vm_flags); |
023bdd00 | 5556 | huge_ptep_modify_prot_commit(vma, address, ptep, old_pte, pte); |
7da4d641 | 5557 | pages++; |
8f860591 | 5558 | } |
cb900f41 | 5559 | spin_unlock(ptl); |
8f860591 | 5560 | } |
d833352a | 5561 | /* |
c8c06efa | 5562 | * Must flush TLB before releasing i_mmap_rwsem: x86's huge_pmd_unshare |
d833352a | 5563 | * may have cleared our pud entry and done put_page on the page table: |
c8c06efa | 5564 | * once we release i_mmap_rwsem, another task can do the final put_page |
dff11abe MK |
5565 | * and that page table be reused and filled with junk. If we actually |
5566 | * did unshare a page of pmds, flush the range corresponding to the pud. | |
d833352a | 5567 | */ |
dff11abe | 5568 | if (shared_pmd) |
ac46d4f3 | 5569 | flush_hugetlb_tlb_range(vma, range.start, range.end); |
dff11abe MK |
5570 | else |
5571 | flush_hugetlb_tlb_range(vma, start, end); | |
0f10851e JG |
5572 | /* |
5573 | * No need to call mmu_notifier_invalidate_range() we are downgrading | |
5574 | * page table protection not changing it to point to a new page. | |
5575 | * | |
ad56b738 | 5576 | * See Documentation/vm/mmu_notifier.rst |
0f10851e | 5577 | */ |
83cde9e8 | 5578 | i_mmap_unlock_write(vma->vm_file->f_mapping); |
ac46d4f3 | 5579 | mmu_notifier_invalidate_range_end(&range); |
7da4d641 PZ |
5580 | |
5581 | return pages << h->order; | |
8f860591 ZY |
5582 | } |
5583 | ||
33b8f84a MK |
5584 | /* Return true if reservation was successful, false otherwise. */ |
5585 | bool hugetlb_reserve_pages(struct inode *inode, | |
a1e78772 | 5586 | long from, long to, |
5a6fe125 | 5587 | struct vm_area_struct *vma, |
ca16d140 | 5588 | vm_flags_t vm_flags) |
e4e574b7 | 5589 | { |
33b8f84a | 5590 | long chg, add = -1; |
a5516438 | 5591 | struct hstate *h = hstate_inode(inode); |
90481622 | 5592 | struct hugepage_subpool *spool = subpool_inode(inode); |
9119a41e | 5593 | struct resv_map *resv_map; |
075a61d0 | 5594 | struct hugetlb_cgroup *h_cg = NULL; |
0db9d74e | 5595 | long gbl_reserve, regions_needed = 0; |
e4e574b7 | 5596 | |
63489f8e MK |
5597 | /* This should never happen */ |
5598 | if (from > to) { | |
5599 | VM_WARN(1, "%s called with a negative range\n", __func__); | |
33b8f84a | 5600 | return false; |
63489f8e MK |
5601 | } |
5602 | ||
17c9d12e MG |
5603 | /* |
5604 | * Only apply hugepage reservation if asked. At fault time, an | |
5605 | * attempt will be made for VM_NORESERVE to allocate a page | |
90481622 | 5606 | * without using reserves |
17c9d12e | 5607 | */ |
ca16d140 | 5608 | if (vm_flags & VM_NORESERVE) |
33b8f84a | 5609 | return true; |
17c9d12e | 5610 | |
a1e78772 MG |
5611 | /* |
5612 | * Shared mappings base their reservation on the number of pages that | |
5613 | * are already allocated on behalf of the file. Private mappings need | |
5614 | * to reserve the full area even if read-only as mprotect() may be | |
5615 | * called to make the mapping read-write. Assume !vma is a shm mapping | |
5616 | */ | |
9119a41e | 5617 | if (!vma || vma->vm_flags & VM_MAYSHARE) { |
f27a5136 MK |
5618 | /* |
5619 | * resv_map can not be NULL as hugetlb_reserve_pages is only | |
5620 | * called for inodes for which resv_maps were created (see | |
5621 | * hugetlbfs_get_inode). | |
5622 | */ | |
4e35f483 | 5623 | resv_map = inode_resv_map(inode); |
9119a41e | 5624 | |
0db9d74e | 5625 | chg = region_chg(resv_map, from, to, ®ions_needed); |
9119a41e JK |
5626 | |
5627 | } else { | |
e9fe92ae | 5628 | /* Private mapping. */ |
9119a41e | 5629 | resv_map = resv_map_alloc(); |
17c9d12e | 5630 | if (!resv_map) |
33b8f84a | 5631 | return false; |
17c9d12e | 5632 | |
a1e78772 | 5633 | chg = to - from; |
84afd99b | 5634 | |
17c9d12e MG |
5635 | set_vma_resv_map(vma, resv_map); |
5636 | set_vma_resv_flags(vma, HPAGE_RESV_OWNER); | |
5637 | } | |
5638 | ||
33b8f84a | 5639 | if (chg < 0) |
c50ac050 | 5640 | goto out_err; |
8a630112 | 5641 | |
33b8f84a MK |
5642 | if (hugetlb_cgroup_charge_cgroup_rsvd(hstate_index(h), |
5643 | chg * pages_per_huge_page(h), &h_cg) < 0) | |
075a61d0 | 5644 | goto out_err; |
075a61d0 MA |
5645 | |
5646 | if (vma && !(vma->vm_flags & VM_MAYSHARE) && h_cg) { | |
5647 | /* For private mappings, the hugetlb_cgroup uncharge info hangs | |
5648 | * of the resv_map. | |
5649 | */ | |
5650 | resv_map_set_hugetlb_cgroup_uncharge_info(resv_map, h_cg, h); | |
5651 | } | |
5652 | ||
1c5ecae3 MK |
5653 | /* |
5654 | * There must be enough pages in the subpool for the mapping. If | |
5655 | * the subpool has a minimum size, there may be some global | |
5656 | * reservations already in place (gbl_reserve). | |
5657 | */ | |
5658 | gbl_reserve = hugepage_subpool_get_pages(spool, chg); | |
33b8f84a | 5659 | if (gbl_reserve < 0) |
075a61d0 | 5660 | goto out_uncharge_cgroup; |
5a6fe125 MG |
5661 | |
5662 | /* | |
17c9d12e | 5663 | * Check enough hugepages are available for the reservation. |
90481622 | 5664 | * Hand the pages back to the subpool if there are not |
5a6fe125 | 5665 | */ |
33b8f84a | 5666 | if (hugetlb_acct_memory(h, gbl_reserve) < 0) |
075a61d0 | 5667 | goto out_put_pages; |
17c9d12e MG |
5668 | |
5669 | /* | |
5670 | * Account for the reservations made. Shared mappings record regions | |
5671 | * that have reservations as they are shared by multiple VMAs. | |
5672 | * When the last VMA disappears, the region map says how much | |
5673 | * the reservation was and the page cache tells how much of | |
5674 | * the reservation was consumed. Private mappings are per-VMA and | |
5675 | * only the consumed reservations are tracked. When the VMA | |
5676 | * disappears, the original reservation is the VMA size and the | |
5677 | * consumed reservations are stored in the map. Hence, nothing | |
5678 | * else has to be done for private mappings here | |
5679 | */ | |
33039678 | 5680 | if (!vma || vma->vm_flags & VM_MAYSHARE) { |
075a61d0 | 5681 | add = region_add(resv_map, from, to, regions_needed, h, h_cg); |
0db9d74e MA |
5682 | |
5683 | if (unlikely(add < 0)) { | |
5684 | hugetlb_acct_memory(h, -gbl_reserve); | |
075a61d0 | 5685 | goto out_put_pages; |
0db9d74e | 5686 | } else if (unlikely(chg > add)) { |
33039678 MK |
5687 | /* |
5688 | * pages in this range were added to the reserve | |
5689 | * map between region_chg and region_add. This | |
5690 | * indicates a race with alloc_huge_page. Adjust | |
5691 | * the subpool and reserve counts modified above | |
5692 | * based on the difference. | |
5693 | */ | |
5694 | long rsv_adjust; | |
5695 | ||
d85aecf2 ML |
5696 | /* |
5697 | * hugetlb_cgroup_uncharge_cgroup_rsvd() will put the | |
5698 | * reference to h_cg->css. See comment below for detail. | |
5699 | */ | |
075a61d0 MA |
5700 | hugetlb_cgroup_uncharge_cgroup_rsvd( |
5701 | hstate_index(h), | |
5702 | (chg - add) * pages_per_huge_page(h), h_cg); | |
5703 | ||
33039678 MK |
5704 | rsv_adjust = hugepage_subpool_put_pages(spool, |
5705 | chg - add); | |
5706 | hugetlb_acct_memory(h, -rsv_adjust); | |
d85aecf2 ML |
5707 | } else if (h_cg) { |
5708 | /* | |
5709 | * The file_regions will hold their own reference to | |
5710 | * h_cg->css. So we should release the reference held | |
5711 | * via hugetlb_cgroup_charge_cgroup_rsvd() when we are | |
5712 | * done. | |
5713 | */ | |
5714 | hugetlb_cgroup_put_rsvd_cgroup(h_cg); | |
33039678 MK |
5715 | } |
5716 | } | |
33b8f84a MK |
5717 | return true; |
5718 | ||
075a61d0 MA |
5719 | out_put_pages: |
5720 | /* put back original number of pages, chg */ | |
5721 | (void)hugepage_subpool_put_pages(spool, chg); | |
5722 | out_uncharge_cgroup: | |
5723 | hugetlb_cgroup_uncharge_cgroup_rsvd(hstate_index(h), | |
5724 | chg * pages_per_huge_page(h), h_cg); | |
c50ac050 | 5725 | out_err: |
5e911373 | 5726 | if (!vma || vma->vm_flags & VM_MAYSHARE) |
0db9d74e MA |
5727 | /* Only call region_abort if the region_chg succeeded but the |
5728 | * region_add failed or didn't run. | |
5729 | */ | |
5730 | if (chg >= 0 && add < 0) | |
5731 | region_abort(resv_map, from, to, regions_needed); | |
f031dd27 JK |
5732 | if (vma && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) |
5733 | kref_put(&resv_map->refs, resv_map_release); | |
33b8f84a | 5734 | return false; |
a43a8c39 CK |
5735 | } |
5736 | ||
b5cec28d MK |
5737 | long hugetlb_unreserve_pages(struct inode *inode, long start, long end, |
5738 | long freed) | |
a43a8c39 | 5739 | { |
a5516438 | 5740 | struct hstate *h = hstate_inode(inode); |
4e35f483 | 5741 | struct resv_map *resv_map = inode_resv_map(inode); |
9119a41e | 5742 | long chg = 0; |
90481622 | 5743 | struct hugepage_subpool *spool = subpool_inode(inode); |
1c5ecae3 | 5744 | long gbl_reserve; |
45c682a6 | 5745 | |
f27a5136 MK |
5746 | /* |
5747 | * Since this routine can be called in the evict inode path for all | |
5748 | * hugetlbfs inodes, resv_map could be NULL. | |
5749 | */ | |
b5cec28d MK |
5750 | if (resv_map) { |
5751 | chg = region_del(resv_map, start, end); | |
5752 | /* | |
5753 | * region_del() can fail in the rare case where a region | |
5754 | * must be split and another region descriptor can not be | |
5755 | * allocated. If end == LONG_MAX, it will not fail. | |
5756 | */ | |
5757 | if (chg < 0) | |
5758 | return chg; | |
5759 | } | |
5760 | ||
45c682a6 | 5761 | spin_lock(&inode->i_lock); |
e4c6f8be | 5762 | inode->i_blocks -= (blocks_per_huge_page(h) * freed); |
45c682a6 KC |
5763 | spin_unlock(&inode->i_lock); |
5764 | ||
1c5ecae3 MK |
5765 | /* |
5766 | * If the subpool has a minimum size, the number of global | |
5767 | * reservations to be released may be adjusted. | |
dddf31a4 ML |
5768 | * |
5769 | * Note that !resv_map implies freed == 0. So (chg - freed) | |
5770 | * won't go negative. | |
1c5ecae3 MK |
5771 | */ |
5772 | gbl_reserve = hugepage_subpool_put_pages(spool, (chg - freed)); | |
5773 | hugetlb_acct_memory(h, -gbl_reserve); | |
b5cec28d MK |
5774 | |
5775 | return 0; | |
a43a8c39 | 5776 | } |
93f70f90 | 5777 | |
3212b535 SC |
5778 | #ifdef CONFIG_ARCH_WANT_HUGE_PMD_SHARE |
5779 | static unsigned long page_table_shareable(struct vm_area_struct *svma, | |
5780 | struct vm_area_struct *vma, | |
5781 | unsigned long addr, pgoff_t idx) | |
5782 | { | |
5783 | unsigned long saddr = ((idx - svma->vm_pgoff) << PAGE_SHIFT) + | |
5784 | svma->vm_start; | |
5785 | unsigned long sbase = saddr & PUD_MASK; | |
5786 | unsigned long s_end = sbase + PUD_SIZE; | |
5787 | ||
5788 | /* Allow segments to share if only one is marked locked */ | |
de60f5f1 EM |
5789 | unsigned long vm_flags = vma->vm_flags & VM_LOCKED_CLEAR_MASK; |
5790 | unsigned long svm_flags = svma->vm_flags & VM_LOCKED_CLEAR_MASK; | |
3212b535 SC |
5791 | |
5792 | /* | |
5793 | * match the virtual addresses, permission and the alignment of the | |
5794 | * page table page. | |
5795 | */ | |
5796 | if (pmd_index(addr) != pmd_index(saddr) || | |
5797 | vm_flags != svm_flags || | |
07e51edf | 5798 | !range_in_vma(svma, sbase, s_end)) |
3212b535 SC |
5799 | return 0; |
5800 | ||
5801 | return saddr; | |
5802 | } | |
5803 | ||
31aafb45 | 5804 | static bool vma_shareable(struct vm_area_struct *vma, unsigned long addr) |
3212b535 SC |
5805 | { |
5806 | unsigned long base = addr & PUD_MASK; | |
5807 | unsigned long end = base + PUD_SIZE; | |
5808 | ||
5809 | /* | |
5810 | * check on proper vm_flags and page table alignment | |
5811 | */ | |
017b1660 | 5812 | if (vma->vm_flags & VM_MAYSHARE && range_in_vma(vma, base, end)) |
31aafb45 NK |
5813 | return true; |
5814 | return false; | |
3212b535 SC |
5815 | } |
5816 | ||
c1991e07 PX |
5817 | bool want_pmd_share(struct vm_area_struct *vma, unsigned long addr) |
5818 | { | |
5819 | #ifdef CONFIG_USERFAULTFD | |
5820 | if (uffd_disable_huge_pmd_share(vma)) | |
5821 | return false; | |
5822 | #endif | |
5823 | return vma_shareable(vma, addr); | |
5824 | } | |
5825 | ||
017b1660 MK |
5826 | /* |
5827 | * Determine if start,end range within vma could be mapped by shared pmd. | |
5828 | * If yes, adjust start and end to cover range associated with possible | |
5829 | * shared pmd mappings. | |
5830 | */ | |
5831 | void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma, | |
5832 | unsigned long *start, unsigned long *end) | |
5833 | { | |
a1ba9da8 LX |
5834 | unsigned long v_start = ALIGN(vma->vm_start, PUD_SIZE), |
5835 | v_end = ALIGN_DOWN(vma->vm_end, PUD_SIZE); | |
017b1660 | 5836 | |
a1ba9da8 | 5837 | /* |
f0953a1b IM |
5838 | * vma needs to span at least one aligned PUD size, and the range |
5839 | * must be at least partially within in. | |
a1ba9da8 LX |
5840 | */ |
5841 | if (!(vma->vm_flags & VM_MAYSHARE) || !(v_end > v_start) || | |
5842 | (*end <= v_start) || (*start >= v_end)) | |
017b1660 MK |
5843 | return; |
5844 | ||
75802ca6 | 5845 | /* Extend the range to be PUD aligned for a worst case scenario */ |
a1ba9da8 LX |
5846 | if (*start > v_start) |
5847 | *start = ALIGN_DOWN(*start, PUD_SIZE); | |
017b1660 | 5848 | |
a1ba9da8 LX |
5849 | if (*end < v_end) |
5850 | *end = ALIGN(*end, PUD_SIZE); | |
017b1660 MK |
5851 | } |
5852 | ||
3212b535 SC |
5853 | /* |
5854 | * Search for a shareable pmd page for hugetlb. In any case calls pmd_alloc() | |
5855 | * and returns the corresponding pte. While this is not necessary for the | |
5856 | * !shared pmd case because we can allocate the pmd later as well, it makes the | |
c0d0381a MK |
5857 | * code much cleaner. |
5858 | * | |
0bf7b64e MK |
5859 | * This routine must be called with i_mmap_rwsem held in at least read mode if |
5860 | * sharing is possible. For hugetlbfs, this prevents removal of any page | |
5861 | * table entries associated with the address space. This is important as we | |
5862 | * are setting up sharing based on existing page table entries (mappings). | |
5863 | * | |
5864 | * NOTE: This routine is only called from huge_pte_alloc. Some callers of | |
5865 | * huge_pte_alloc know that sharing is not possible and do not take | |
5866 | * i_mmap_rwsem as a performance optimization. This is handled by the | |
5867 | * if !vma_shareable check at the beginning of the routine. i_mmap_rwsem is | |
5868 | * only required for subsequent processing. | |
3212b535 | 5869 | */ |
aec44e0f PX |
5870 | pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma, |
5871 | unsigned long addr, pud_t *pud) | |
3212b535 | 5872 | { |
3212b535 SC |
5873 | struct address_space *mapping = vma->vm_file->f_mapping; |
5874 | pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) + | |
5875 | vma->vm_pgoff; | |
5876 | struct vm_area_struct *svma; | |
5877 | unsigned long saddr; | |
5878 | pte_t *spte = NULL; | |
5879 | pte_t *pte; | |
cb900f41 | 5880 | spinlock_t *ptl; |
3212b535 | 5881 | |
0bf7b64e | 5882 | i_mmap_assert_locked(mapping); |
3212b535 SC |
5883 | vma_interval_tree_foreach(svma, &mapping->i_mmap, idx, idx) { |
5884 | if (svma == vma) | |
5885 | continue; | |
5886 | ||
5887 | saddr = page_table_shareable(svma, vma, addr, idx); | |
5888 | if (saddr) { | |
7868a208 PA |
5889 | spte = huge_pte_offset(svma->vm_mm, saddr, |
5890 | vma_mmu_pagesize(svma)); | |
3212b535 SC |
5891 | if (spte) { |
5892 | get_page(virt_to_page(spte)); | |
5893 | break; | |
5894 | } | |
5895 | } | |
5896 | } | |
5897 | ||
5898 | if (!spte) | |
5899 | goto out; | |
5900 | ||
8bea8052 | 5901 | ptl = huge_pte_lock(hstate_vma(vma), mm, spte); |
dc6c9a35 | 5902 | if (pud_none(*pud)) { |
3212b535 SC |
5903 | pud_populate(mm, pud, |
5904 | (pmd_t *)((unsigned long)spte & PAGE_MASK)); | |
c17b1f42 | 5905 | mm_inc_nr_pmds(mm); |
dc6c9a35 | 5906 | } else { |
3212b535 | 5907 | put_page(virt_to_page(spte)); |
dc6c9a35 | 5908 | } |
cb900f41 | 5909 | spin_unlock(ptl); |
3212b535 SC |
5910 | out: |
5911 | pte = (pte_t *)pmd_alloc(mm, pud, addr); | |
3212b535 SC |
5912 | return pte; |
5913 | } | |
5914 | ||
5915 | /* | |
5916 | * unmap huge page backed by shared pte. | |
5917 | * | |
5918 | * Hugetlb pte page is ref counted at the time of mapping. If pte is shared | |
5919 | * indicated by page_count > 1, unmap is achieved by clearing pud and | |
5920 | * decrementing the ref count. If count == 1, the pte page is not shared. | |
5921 | * | |
c0d0381a | 5922 | * Called with page table lock held and i_mmap_rwsem held in write mode. |
3212b535 SC |
5923 | * |
5924 | * returns: 1 successfully unmapped a shared pte page | |
5925 | * 0 the underlying pte page is not shared, or it is the last user | |
5926 | */ | |
34ae204f MK |
5927 | int huge_pmd_unshare(struct mm_struct *mm, struct vm_area_struct *vma, |
5928 | unsigned long *addr, pte_t *ptep) | |
3212b535 SC |
5929 | { |
5930 | pgd_t *pgd = pgd_offset(mm, *addr); | |
c2febafc KS |
5931 | p4d_t *p4d = p4d_offset(pgd, *addr); |
5932 | pud_t *pud = pud_offset(p4d, *addr); | |
3212b535 | 5933 | |
34ae204f | 5934 | i_mmap_assert_write_locked(vma->vm_file->f_mapping); |
3212b535 SC |
5935 | BUG_ON(page_count(virt_to_page(ptep)) == 0); |
5936 | if (page_count(virt_to_page(ptep)) == 1) | |
5937 | return 0; | |
5938 | ||
5939 | pud_clear(pud); | |
5940 | put_page(virt_to_page(ptep)); | |
dc6c9a35 | 5941 | mm_dec_nr_pmds(mm); |
3212b535 SC |
5942 | *addr = ALIGN(*addr, HPAGE_SIZE * PTRS_PER_PTE) - HPAGE_SIZE; |
5943 | return 1; | |
5944 | } | |
c1991e07 | 5945 | |
9e5fc74c | 5946 | #else /* !CONFIG_ARCH_WANT_HUGE_PMD_SHARE */ |
aec44e0f PX |
5947 | pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma, |
5948 | unsigned long addr, pud_t *pud) | |
9e5fc74c SC |
5949 | { |
5950 | return NULL; | |
5951 | } | |
e81f2d22 | 5952 | |
34ae204f MK |
5953 | int huge_pmd_unshare(struct mm_struct *mm, struct vm_area_struct *vma, |
5954 | unsigned long *addr, pte_t *ptep) | |
e81f2d22 ZZ |
5955 | { |
5956 | return 0; | |
5957 | } | |
017b1660 MK |
5958 | |
5959 | void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma, | |
5960 | unsigned long *start, unsigned long *end) | |
5961 | { | |
5962 | } | |
c1991e07 PX |
5963 | |
5964 | bool want_pmd_share(struct vm_area_struct *vma, unsigned long addr) | |
5965 | { | |
5966 | return false; | |
5967 | } | |
3212b535 SC |
5968 | #endif /* CONFIG_ARCH_WANT_HUGE_PMD_SHARE */ |
5969 | ||
9e5fc74c | 5970 | #ifdef CONFIG_ARCH_WANT_GENERAL_HUGETLB |
aec44e0f | 5971 | pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, |
9e5fc74c SC |
5972 | unsigned long addr, unsigned long sz) |
5973 | { | |
5974 | pgd_t *pgd; | |
c2febafc | 5975 | p4d_t *p4d; |
9e5fc74c SC |
5976 | pud_t *pud; |
5977 | pte_t *pte = NULL; | |
5978 | ||
5979 | pgd = pgd_offset(mm, addr); | |
f4f0a3d8 KS |
5980 | p4d = p4d_alloc(mm, pgd, addr); |
5981 | if (!p4d) | |
5982 | return NULL; | |
c2febafc | 5983 | pud = pud_alloc(mm, p4d, addr); |
9e5fc74c SC |
5984 | if (pud) { |
5985 | if (sz == PUD_SIZE) { | |
5986 | pte = (pte_t *)pud; | |
5987 | } else { | |
5988 | BUG_ON(sz != PMD_SIZE); | |
c1991e07 | 5989 | if (want_pmd_share(vma, addr) && pud_none(*pud)) |
aec44e0f | 5990 | pte = huge_pmd_share(mm, vma, addr, pud); |
9e5fc74c SC |
5991 | else |
5992 | pte = (pte_t *)pmd_alloc(mm, pud, addr); | |
5993 | } | |
5994 | } | |
4e666314 | 5995 | BUG_ON(pte && pte_present(*pte) && !pte_huge(*pte)); |
9e5fc74c SC |
5996 | |
5997 | return pte; | |
5998 | } | |
5999 | ||
9b19df29 PA |
6000 | /* |
6001 | * huge_pte_offset() - Walk the page table to resolve the hugepage | |
6002 | * entry at address @addr | |
6003 | * | |
8ac0b81a LX |
6004 | * Return: Pointer to page table entry (PUD or PMD) for |
6005 | * address @addr, or NULL if a !p*d_present() entry is encountered and the | |
9b19df29 PA |
6006 | * size @sz doesn't match the hugepage size at this level of the page |
6007 | * table. | |
6008 | */ | |
7868a208 PA |
6009 | pte_t *huge_pte_offset(struct mm_struct *mm, |
6010 | unsigned long addr, unsigned long sz) | |
9e5fc74c SC |
6011 | { |
6012 | pgd_t *pgd; | |
c2febafc | 6013 | p4d_t *p4d; |
8ac0b81a LX |
6014 | pud_t *pud; |
6015 | pmd_t *pmd; | |
9e5fc74c SC |
6016 | |
6017 | pgd = pgd_offset(mm, addr); | |
c2febafc KS |
6018 | if (!pgd_present(*pgd)) |
6019 | return NULL; | |
6020 | p4d = p4d_offset(pgd, addr); | |
6021 | if (!p4d_present(*p4d)) | |
6022 | return NULL; | |
9b19df29 | 6023 | |
c2febafc | 6024 | pud = pud_offset(p4d, addr); |
8ac0b81a LX |
6025 | if (sz == PUD_SIZE) |
6026 | /* must be pud huge, non-present or none */ | |
c2febafc | 6027 | return (pte_t *)pud; |
8ac0b81a | 6028 | if (!pud_present(*pud)) |
9b19df29 | 6029 | return NULL; |
8ac0b81a | 6030 | /* must have a valid entry and size to go further */ |
9b19df29 | 6031 | |
8ac0b81a LX |
6032 | pmd = pmd_offset(pud, addr); |
6033 | /* must be pmd huge, non-present or none */ | |
6034 | return (pte_t *)pmd; | |
9e5fc74c SC |
6035 | } |
6036 | ||
61f77eda NH |
6037 | #endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */ |
6038 | ||
6039 | /* | |
6040 | * These functions are overwritable if your architecture needs its own | |
6041 | * behavior. | |
6042 | */ | |
6043 | struct page * __weak | |
6044 | follow_huge_addr(struct mm_struct *mm, unsigned long address, | |
6045 | int write) | |
6046 | { | |
6047 | return ERR_PTR(-EINVAL); | |
6048 | } | |
6049 | ||
4dc71451 AK |
6050 | struct page * __weak |
6051 | follow_huge_pd(struct vm_area_struct *vma, | |
6052 | unsigned long address, hugepd_t hpd, int flags, int pdshift) | |
6053 | { | |
6054 | WARN(1, "hugepd follow called with no support for hugepage directory format\n"); | |
6055 | return NULL; | |
6056 | } | |
6057 | ||
61f77eda | 6058 | struct page * __weak |
9e5fc74c | 6059 | follow_huge_pmd(struct mm_struct *mm, unsigned long address, |
e66f17ff | 6060 | pmd_t *pmd, int flags) |
9e5fc74c | 6061 | { |
e66f17ff NH |
6062 | struct page *page = NULL; |
6063 | spinlock_t *ptl; | |
c9d398fa | 6064 | pte_t pte; |
3faa52c0 JH |
6065 | |
6066 | /* FOLL_GET and FOLL_PIN are mutually exclusive. */ | |
6067 | if (WARN_ON_ONCE((flags & (FOLL_PIN | FOLL_GET)) == | |
6068 | (FOLL_PIN | FOLL_GET))) | |
6069 | return NULL; | |
6070 | ||
e66f17ff NH |
6071 | retry: |
6072 | ptl = pmd_lockptr(mm, pmd); | |
6073 | spin_lock(ptl); | |
6074 | /* | |
6075 | * make sure that the address range covered by this pmd is not | |
6076 | * unmapped from other threads. | |
6077 | */ | |
6078 | if (!pmd_huge(*pmd)) | |
6079 | goto out; | |
c9d398fa NH |
6080 | pte = huge_ptep_get((pte_t *)pmd); |
6081 | if (pte_present(pte)) { | |
97534127 | 6082 | page = pmd_page(*pmd) + ((address & ~PMD_MASK) >> PAGE_SHIFT); |
3faa52c0 JH |
6083 | /* |
6084 | * try_grab_page() should always succeed here, because: a) we | |
6085 | * hold the pmd (ptl) lock, and b) we've just checked that the | |
6086 | * huge pmd (head) page is present in the page tables. The ptl | |
6087 | * prevents the head page and tail pages from being rearranged | |
6088 | * in any way. So this page must be available at this point, | |
6089 | * unless the page refcount overflowed: | |
6090 | */ | |
6091 | if (WARN_ON_ONCE(!try_grab_page(page, flags))) { | |
6092 | page = NULL; | |
6093 | goto out; | |
6094 | } | |
e66f17ff | 6095 | } else { |
c9d398fa | 6096 | if (is_hugetlb_entry_migration(pte)) { |
e66f17ff NH |
6097 | spin_unlock(ptl); |
6098 | __migration_entry_wait(mm, (pte_t *)pmd, ptl); | |
6099 | goto retry; | |
6100 | } | |
6101 | /* | |
6102 | * hwpoisoned entry is treated as no_page_table in | |
6103 | * follow_page_mask(). | |
6104 | */ | |
6105 | } | |
6106 | out: | |
6107 | spin_unlock(ptl); | |
9e5fc74c SC |
6108 | return page; |
6109 | } | |
6110 | ||
61f77eda | 6111 | struct page * __weak |
9e5fc74c | 6112 | follow_huge_pud(struct mm_struct *mm, unsigned long address, |
e66f17ff | 6113 | pud_t *pud, int flags) |
9e5fc74c | 6114 | { |
3faa52c0 | 6115 | if (flags & (FOLL_GET | FOLL_PIN)) |
e66f17ff | 6116 | return NULL; |
9e5fc74c | 6117 | |
e66f17ff | 6118 | return pte_page(*(pte_t *)pud) + ((address & ~PUD_MASK) >> PAGE_SHIFT); |
9e5fc74c SC |
6119 | } |
6120 | ||
faaa5b62 AK |
6121 | struct page * __weak |
6122 | follow_huge_pgd(struct mm_struct *mm, unsigned long address, pgd_t *pgd, int flags) | |
6123 | { | |
3faa52c0 | 6124 | if (flags & (FOLL_GET | FOLL_PIN)) |
faaa5b62 AK |
6125 | return NULL; |
6126 | ||
6127 | return pte_page(*(pte_t *)pgd) + ((address & ~PGDIR_MASK) >> PAGE_SHIFT); | |
6128 | } | |
6129 | ||
31caf665 NH |
6130 | bool isolate_huge_page(struct page *page, struct list_head *list) |
6131 | { | |
bcc54222 NH |
6132 | bool ret = true; |
6133 | ||
db71ef79 | 6134 | spin_lock_irq(&hugetlb_lock); |
8f251a3d MK |
6135 | if (!PageHeadHuge(page) || |
6136 | !HPageMigratable(page) || | |
0eb2df2b | 6137 | !get_page_unless_zero(page)) { |
bcc54222 NH |
6138 | ret = false; |
6139 | goto unlock; | |
6140 | } | |
8f251a3d | 6141 | ClearHPageMigratable(page); |
31caf665 | 6142 | list_move_tail(&page->lru, list); |
bcc54222 | 6143 | unlock: |
db71ef79 | 6144 | spin_unlock_irq(&hugetlb_lock); |
bcc54222 | 6145 | return ret; |
31caf665 NH |
6146 | } |
6147 | ||
25182f05 NH |
6148 | int get_hwpoison_huge_page(struct page *page, bool *hugetlb) |
6149 | { | |
6150 | int ret = 0; | |
6151 | ||
6152 | *hugetlb = false; | |
6153 | spin_lock_irq(&hugetlb_lock); | |
6154 | if (PageHeadHuge(page)) { | |
6155 | *hugetlb = true; | |
6156 | if (HPageFreed(page) || HPageMigratable(page)) | |
6157 | ret = get_page_unless_zero(page); | |
0ed950d1 NH |
6158 | else |
6159 | ret = -EBUSY; | |
25182f05 NH |
6160 | } |
6161 | spin_unlock_irq(&hugetlb_lock); | |
6162 | return ret; | |
6163 | } | |
6164 | ||
31caf665 NH |
6165 | void putback_active_hugepage(struct page *page) |
6166 | { | |
db71ef79 | 6167 | spin_lock_irq(&hugetlb_lock); |
8f251a3d | 6168 | SetHPageMigratable(page); |
31caf665 | 6169 | list_move_tail(&page->lru, &(page_hstate(page))->hugepage_activelist); |
db71ef79 | 6170 | spin_unlock_irq(&hugetlb_lock); |
31caf665 NH |
6171 | put_page(page); |
6172 | } | |
ab5ac90a MH |
6173 | |
6174 | void move_hugetlb_state(struct page *oldpage, struct page *newpage, int reason) | |
6175 | { | |
6176 | struct hstate *h = page_hstate(oldpage); | |
6177 | ||
6178 | hugetlb_cgroup_migrate(oldpage, newpage); | |
6179 | set_page_owner_migrate_reason(newpage, reason); | |
6180 | ||
6181 | /* | |
6182 | * transfer temporary state of the new huge page. This is | |
6183 | * reverse to other transitions because the newpage is going to | |
6184 | * be final while the old one will be freed so it takes over | |
6185 | * the temporary status. | |
6186 | * | |
6187 | * Also note that we have to transfer the per-node surplus state | |
6188 | * here as well otherwise the global surplus count will not match | |
6189 | * the per-node's. | |
6190 | */ | |
9157c311 | 6191 | if (HPageTemporary(newpage)) { |
ab5ac90a MH |
6192 | int old_nid = page_to_nid(oldpage); |
6193 | int new_nid = page_to_nid(newpage); | |
6194 | ||
9157c311 MK |
6195 | SetHPageTemporary(oldpage); |
6196 | ClearHPageTemporary(newpage); | |
ab5ac90a | 6197 | |
5af1ab1d ML |
6198 | /* |
6199 | * There is no need to transfer the per-node surplus state | |
6200 | * when we do not cross the node. | |
6201 | */ | |
6202 | if (new_nid == old_nid) | |
6203 | return; | |
db71ef79 | 6204 | spin_lock_irq(&hugetlb_lock); |
ab5ac90a MH |
6205 | if (h->surplus_huge_pages_node[old_nid]) { |
6206 | h->surplus_huge_pages_node[old_nid]--; | |
6207 | h->surplus_huge_pages_node[new_nid]++; | |
6208 | } | |
db71ef79 | 6209 | spin_unlock_irq(&hugetlb_lock); |
ab5ac90a MH |
6210 | } |
6211 | } | |
cf11e85f | 6212 | |
6dfeaff9 PX |
6213 | /* |
6214 | * This function will unconditionally remove all the shared pmd pgtable entries | |
6215 | * within the specific vma for a hugetlbfs memory range. | |
6216 | */ | |
6217 | void hugetlb_unshare_all_pmds(struct vm_area_struct *vma) | |
6218 | { | |
6219 | struct hstate *h = hstate_vma(vma); | |
6220 | unsigned long sz = huge_page_size(h); | |
6221 | struct mm_struct *mm = vma->vm_mm; | |
6222 | struct mmu_notifier_range range; | |
6223 | unsigned long address, start, end; | |
6224 | spinlock_t *ptl; | |
6225 | pte_t *ptep; | |
6226 | ||
6227 | if (!(vma->vm_flags & VM_MAYSHARE)) | |
6228 | return; | |
6229 | ||
6230 | start = ALIGN(vma->vm_start, PUD_SIZE); | |
6231 | end = ALIGN_DOWN(vma->vm_end, PUD_SIZE); | |
6232 | ||
6233 | if (start >= end) | |
6234 | return; | |
6235 | ||
6236 | /* | |
6237 | * No need to call adjust_range_if_pmd_sharing_possible(), because | |
6238 | * we have already done the PUD_SIZE alignment. | |
6239 | */ | |
6240 | mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, mm, | |
6241 | start, end); | |
6242 | mmu_notifier_invalidate_range_start(&range); | |
6243 | i_mmap_lock_write(vma->vm_file->f_mapping); | |
6244 | for (address = start; address < end; address += PUD_SIZE) { | |
6245 | unsigned long tmp = address; | |
6246 | ||
6247 | ptep = huge_pte_offset(mm, address, sz); | |
6248 | if (!ptep) | |
6249 | continue; | |
6250 | ptl = huge_pte_lock(h, mm, ptep); | |
6251 | /* We don't want 'address' to be changed */ | |
6252 | huge_pmd_unshare(mm, vma, &tmp, ptep); | |
6253 | spin_unlock(ptl); | |
6254 | } | |
6255 | flush_hugetlb_tlb_range(vma, start, end); | |
6256 | i_mmap_unlock_write(vma->vm_file->f_mapping); | |
6257 | /* | |
6258 | * No need to call mmu_notifier_invalidate_range(), see | |
6259 | * Documentation/vm/mmu_notifier.rst. | |
6260 | */ | |
6261 | mmu_notifier_invalidate_range_end(&range); | |
6262 | } | |
6263 | ||
cf11e85f | 6264 | #ifdef CONFIG_CMA |
cf11e85f RG |
6265 | static bool cma_reserve_called __initdata; |
6266 | ||
6267 | static int __init cmdline_parse_hugetlb_cma(char *p) | |
6268 | { | |
6269 | hugetlb_cma_size = memparse(p, &p); | |
6270 | return 0; | |
6271 | } | |
6272 | ||
6273 | early_param("hugetlb_cma", cmdline_parse_hugetlb_cma); | |
6274 | ||
6275 | void __init hugetlb_cma_reserve(int order) | |
6276 | { | |
6277 | unsigned long size, reserved, per_node; | |
6278 | int nid; | |
6279 | ||
6280 | cma_reserve_called = true; | |
6281 | ||
6282 | if (!hugetlb_cma_size) | |
6283 | return; | |
6284 | ||
6285 | if (hugetlb_cma_size < (PAGE_SIZE << order)) { | |
6286 | pr_warn("hugetlb_cma: cma area should be at least %lu MiB\n", | |
6287 | (PAGE_SIZE << order) / SZ_1M); | |
6288 | return; | |
6289 | } | |
6290 | ||
6291 | /* | |
6292 | * If 3 GB area is requested on a machine with 4 numa nodes, | |
6293 | * let's allocate 1 GB on first three nodes and ignore the last one. | |
6294 | */ | |
6295 | per_node = DIV_ROUND_UP(hugetlb_cma_size, nr_online_nodes); | |
6296 | pr_info("hugetlb_cma: reserve %lu MiB, up to %lu MiB per node\n", | |
6297 | hugetlb_cma_size / SZ_1M, per_node / SZ_1M); | |
6298 | ||
6299 | reserved = 0; | |
6300 | for_each_node_state(nid, N_ONLINE) { | |
6301 | int res; | |
2281f797 | 6302 | char name[CMA_MAX_NAME]; |
cf11e85f RG |
6303 | |
6304 | size = min(per_node, hugetlb_cma_size - reserved); | |
6305 | size = round_up(size, PAGE_SIZE << order); | |
6306 | ||
2281f797 | 6307 | snprintf(name, sizeof(name), "hugetlb%d", nid); |
cf11e85f | 6308 | res = cma_declare_contiguous_nid(0, size, 0, PAGE_SIZE << order, |
29d0f41d | 6309 | 0, false, name, |
cf11e85f RG |
6310 | &hugetlb_cma[nid], nid); |
6311 | if (res) { | |
6312 | pr_warn("hugetlb_cma: reservation failed: err %d, node %d", | |
6313 | res, nid); | |
6314 | continue; | |
6315 | } | |
6316 | ||
6317 | reserved += size; | |
6318 | pr_info("hugetlb_cma: reserved %lu MiB on node %d\n", | |
6319 | size / SZ_1M, nid); | |
6320 | ||
6321 | if (reserved >= hugetlb_cma_size) | |
6322 | break; | |
6323 | } | |
6324 | } | |
6325 | ||
6326 | void __init hugetlb_cma_check(void) | |
6327 | { | |
6328 | if (!hugetlb_cma_size || cma_reserve_called) | |
6329 | return; | |
6330 | ||
6331 | pr_warn("hugetlb_cma: the option isn't supported by current arch\n"); | |
6332 | } | |
6333 | ||
6334 | #endif /* CONFIG_CMA */ |