Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Generic hugetlb support. | |
3 | * (C) William Irwin, April 2004 | |
4 | */ | |
1da177e4 LT |
5 | #include <linux/list.h> |
6 | #include <linux/init.h> | |
7 | #include <linux/module.h> | |
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> |
aea47ff3 | 16 | #include <linux/cpuset.h> |
3935baa9 | 17 | #include <linux/mutex.h> |
aa888a74 | 18 | #include <linux/bootmem.h> |
a3437870 | 19 | #include <linux/sysfs.h> |
5a0e3ad6 | 20 | #include <linux/slab.h> |
0fe6e20b | 21 | #include <linux/rmap.h> |
fd6a03ed NH |
22 | #include <linux/swap.h> |
23 | #include <linux/swapops.h> | |
d6606683 | 24 | |
63551ae0 DG |
25 | #include <asm/page.h> |
26 | #include <asm/pgtable.h> | |
24669e58 | 27 | #include <asm/tlb.h> |
63551ae0 | 28 | |
24669e58 | 29 | #include <linux/io.h> |
63551ae0 | 30 | #include <linux/hugetlb.h> |
9dd540e2 | 31 | #include <linux/hugetlb_cgroup.h> |
9a305230 | 32 | #include <linux/node.h> |
abb8206c | 33 | #include <linux/hugetlb_cgroup.h> |
7835e98b | 34 | #include "internal.h" |
1da177e4 LT |
35 | |
36 | const unsigned long hugetlb_zero = 0, hugetlb_infinity = ~0UL; | |
396faf03 MG |
37 | static gfp_t htlb_alloc_mask = GFP_HIGHUSER; |
38 | unsigned long hugepages_treat_as_movable; | |
a5516438 | 39 | |
c3f38a38 | 40 | int hugetlb_max_hstate __read_mostly; |
e5ff2159 AK |
41 | unsigned int default_hstate_idx; |
42 | struct hstate hstates[HUGE_MAX_HSTATE]; | |
43 | ||
53ba51d2 JT |
44 | __initdata LIST_HEAD(huge_boot_pages); |
45 | ||
e5ff2159 AK |
46 | /* for command line parsing */ |
47 | static struct hstate * __initdata parsed_hstate; | |
48 | static unsigned long __initdata default_hstate_max_huge_pages; | |
e11bfbfc | 49 | static unsigned long __initdata default_hstate_size; |
e5ff2159 | 50 | |
3935baa9 DG |
51 | /* |
52 | * Protects updates to hugepage_freelists, nr_huge_pages, and free_huge_pages | |
53 | */ | |
c3f38a38 | 54 | DEFINE_SPINLOCK(hugetlb_lock); |
0bd0f9fb | 55 | |
90481622 DG |
56 | static inline void unlock_or_release_subpool(struct hugepage_subpool *spool) |
57 | { | |
58 | bool free = (spool->count == 0) && (spool->used_hpages == 0); | |
59 | ||
60 | spin_unlock(&spool->lock); | |
61 | ||
62 | /* If no pages are used, and no other handles to the subpool | |
63 | * remain, free the subpool the subpool remain */ | |
64 | if (free) | |
65 | kfree(spool); | |
66 | } | |
67 | ||
68 | struct hugepage_subpool *hugepage_new_subpool(long nr_blocks) | |
69 | { | |
70 | struct hugepage_subpool *spool; | |
71 | ||
72 | spool = kmalloc(sizeof(*spool), GFP_KERNEL); | |
73 | if (!spool) | |
74 | return NULL; | |
75 | ||
76 | spin_lock_init(&spool->lock); | |
77 | spool->count = 1; | |
78 | spool->max_hpages = nr_blocks; | |
79 | spool->used_hpages = 0; | |
80 | ||
81 | return spool; | |
82 | } | |
83 | ||
84 | void hugepage_put_subpool(struct hugepage_subpool *spool) | |
85 | { | |
86 | spin_lock(&spool->lock); | |
87 | BUG_ON(!spool->count); | |
88 | spool->count--; | |
89 | unlock_or_release_subpool(spool); | |
90 | } | |
91 | ||
92 | static int hugepage_subpool_get_pages(struct hugepage_subpool *spool, | |
93 | long delta) | |
94 | { | |
95 | int ret = 0; | |
96 | ||
97 | if (!spool) | |
98 | return 0; | |
99 | ||
100 | spin_lock(&spool->lock); | |
101 | if ((spool->used_hpages + delta) <= spool->max_hpages) { | |
102 | spool->used_hpages += delta; | |
103 | } else { | |
104 | ret = -ENOMEM; | |
105 | } | |
106 | spin_unlock(&spool->lock); | |
107 | ||
108 | return ret; | |
109 | } | |
110 | ||
111 | static void hugepage_subpool_put_pages(struct hugepage_subpool *spool, | |
112 | long delta) | |
113 | { | |
114 | if (!spool) | |
115 | return; | |
116 | ||
117 | spin_lock(&spool->lock); | |
118 | spool->used_hpages -= delta; | |
119 | /* If hugetlbfs_put_super couldn't free spool due to | |
120 | * an outstanding quota reference, free it now. */ | |
121 | unlock_or_release_subpool(spool); | |
122 | } | |
123 | ||
124 | static inline struct hugepage_subpool *subpool_inode(struct inode *inode) | |
125 | { | |
126 | return HUGETLBFS_SB(inode->i_sb)->spool; | |
127 | } | |
128 | ||
129 | static inline struct hugepage_subpool *subpool_vma(struct vm_area_struct *vma) | |
130 | { | |
131 | return subpool_inode(vma->vm_file->f_dentry->d_inode); | |
132 | } | |
133 | ||
96822904 AW |
134 | /* |
135 | * Region tracking -- allows tracking of reservations and instantiated pages | |
136 | * across the pages in a mapping. | |
84afd99b AW |
137 | * |
138 | * The region data structures are protected by a combination of the mmap_sem | |
139 | * and the hugetlb_instantion_mutex. To access or modify a region the caller | |
140 | * must either hold the mmap_sem for write, or the mmap_sem for read and | |
141 | * the hugetlb_instantiation mutex: | |
142 | * | |
32f84528 | 143 | * down_write(&mm->mmap_sem); |
84afd99b | 144 | * or |
32f84528 CF |
145 | * down_read(&mm->mmap_sem); |
146 | * mutex_lock(&hugetlb_instantiation_mutex); | |
96822904 AW |
147 | */ |
148 | struct file_region { | |
149 | struct list_head link; | |
150 | long from; | |
151 | long to; | |
152 | }; | |
153 | ||
154 | static long region_add(struct list_head *head, long f, long t) | |
155 | { | |
156 | struct file_region *rg, *nrg, *trg; | |
157 | ||
158 | /* Locate the region we are either in or before. */ | |
159 | list_for_each_entry(rg, head, link) | |
160 | if (f <= rg->to) | |
161 | break; | |
162 | ||
163 | /* Round our left edge to the current segment if it encloses us. */ | |
164 | if (f > rg->from) | |
165 | f = rg->from; | |
166 | ||
167 | /* Check for and consume any regions we now overlap with. */ | |
168 | nrg = rg; | |
169 | list_for_each_entry_safe(rg, trg, rg->link.prev, link) { | |
170 | if (&rg->link == head) | |
171 | break; | |
172 | if (rg->from > t) | |
173 | break; | |
174 | ||
175 | /* If this area reaches higher then extend our area to | |
176 | * include it completely. If this is not the first area | |
177 | * which we intend to reuse, free it. */ | |
178 | if (rg->to > t) | |
179 | t = rg->to; | |
180 | if (rg != nrg) { | |
181 | list_del(&rg->link); | |
182 | kfree(rg); | |
183 | } | |
184 | } | |
185 | nrg->from = f; | |
186 | nrg->to = t; | |
187 | return 0; | |
188 | } | |
189 | ||
190 | static long region_chg(struct list_head *head, long f, long t) | |
191 | { | |
192 | struct file_region *rg, *nrg; | |
193 | long chg = 0; | |
194 | ||
195 | /* Locate the region we are before or in. */ | |
196 | list_for_each_entry(rg, head, link) | |
197 | if (f <= rg->to) | |
198 | break; | |
199 | ||
200 | /* If we are below the current region then a new region is required. | |
201 | * Subtle, allocate a new region at the position but make it zero | |
202 | * size such that we can guarantee to record the reservation. */ | |
203 | if (&rg->link == head || t < rg->from) { | |
204 | nrg = kmalloc(sizeof(*nrg), GFP_KERNEL); | |
205 | if (!nrg) | |
206 | return -ENOMEM; | |
207 | nrg->from = f; | |
208 | nrg->to = f; | |
209 | INIT_LIST_HEAD(&nrg->link); | |
210 | list_add(&nrg->link, rg->link.prev); | |
211 | ||
212 | return t - f; | |
213 | } | |
214 | ||
215 | /* Round our left edge to the current segment if it encloses us. */ | |
216 | if (f > rg->from) | |
217 | f = rg->from; | |
218 | chg = t - f; | |
219 | ||
220 | /* Check for and consume any regions we now overlap with. */ | |
221 | list_for_each_entry(rg, rg->link.prev, link) { | |
222 | if (&rg->link == head) | |
223 | break; | |
224 | if (rg->from > t) | |
225 | return chg; | |
226 | ||
25985edc | 227 | /* We overlap with this area, if it extends further than |
96822904 AW |
228 | * us then we must extend ourselves. Account for its |
229 | * existing reservation. */ | |
230 | if (rg->to > t) { | |
231 | chg += rg->to - t; | |
232 | t = rg->to; | |
233 | } | |
234 | chg -= rg->to - rg->from; | |
235 | } | |
236 | return chg; | |
237 | } | |
238 | ||
239 | static long region_truncate(struct list_head *head, long end) | |
240 | { | |
241 | struct file_region *rg, *trg; | |
242 | long chg = 0; | |
243 | ||
244 | /* Locate the region we are either in or before. */ | |
245 | list_for_each_entry(rg, head, link) | |
246 | if (end <= rg->to) | |
247 | break; | |
248 | if (&rg->link == head) | |
249 | return 0; | |
250 | ||
251 | /* If we are in the middle of a region then adjust it. */ | |
252 | if (end > rg->from) { | |
253 | chg = rg->to - end; | |
254 | rg->to = end; | |
255 | rg = list_entry(rg->link.next, typeof(*rg), link); | |
256 | } | |
257 | ||
258 | /* Drop any remaining regions. */ | |
259 | list_for_each_entry_safe(rg, trg, rg->link.prev, link) { | |
260 | if (&rg->link == head) | |
261 | break; | |
262 | chg += rg->to - rg->from; | |
263 | list_del(&rg->link); | |
264 | kfree(rg); | |
265 | } | |
266 | return chg; | |
267 | } | |
268 | ||
84afd99b AW |
269 | static long region_count(struct list_head *head, long f, long t) |
270 | { | |
271 | struct file_region *rg; | |
272 | long chg = 0; | |
273 | ||
274 | /* Locate each segment we overlap with, and count that overlap. */ | |
275 | list_for_each_entry(rg, head, link) { | |
f2135a4a WSH |
276 | long seg_from; |
277 | long seg_to; | |
84afd99b AW |
278 | |
279 | if (rg->to <= f) | |
280 | continue; | |
281 | if (rg->from >= t) | |
282 | break; | |
283 | ||
284 | seg_from = max(rg->from, f); | |
285 | seg_to = min(rg->to, t); | |
286 | ||
287 | chg += seg_to - seg_from; | |
288 | } | |
289 | ||
290 | return chg; | |
291 | } | |
292 | ||
e7c4b0bf AW |
293 | /* |
294 | * Convert the address within this vma to the page offset within | |
295 | * the mapping, in pagecache page units; huge pages here. | |
296 | */ | |
a5516438 AK |
297 | static pgoff_t vma_hugecache_offset(struct hstate *h, |
298 | struct vm_area_struct *vma, unsigned long address) | |
e7c4b0bf | 299 | { |
a5516438 AK |
300 | return ((address - vma->vm_start) >> huge_page_shift(h)) + |
301 | (vma->vm_pgoff >> huge_page_order(h)); | |
e7c4b0bf AW |
302 | } |
303 | ||
0fe6e20b NH |
304 | pgoff_t linear_hugepage_index(struct vm_area_struct *vma, |
305 | unsigned long address) | |
306 | { | |
307 | return vma_hugecache_offset(hstate_vma(vma), vma, address); | |
308 | } | |
309 | ||
08fba699 MG |
310 | /* |
311 | * Return the size of the pages allocated when backing a VMA. In the majority | |
312 | * cases this will be same size as used by the page table entries. | |
313 | */ | |
314 | unsigned long vma_kernel_pagesize(struct vm_area_struct *vma) | |
315 | { | |
316 | struct hstate *hstate; | |
317 | ||
318 | if (!is_vm_hugetlb_page(vma)) | |
319 | return PAGE_SIZE; | |
320 | ||
321 | hstate = hstate_vma(vma); | |
322 | ||
323 | return 1UL << (hstate->order + PAGE_SHIFT); | |
324 | } | |
f340ca0f | 325 | EXPORT_SYMBOL_GPL(vma_kernel_pagesize); |
08fba699 | 326 | |
3340289d MG |
327 | /* |
328 | * Return the page size being used by the MMU to back a VMA. In the majority | |
329 | * of cases, the page size used by the kernel matches the MMU size. On | |
330 | * architectures where it differs, an architecture-specific version of this | |
331 | * function is required. | |
332 | */ | |
333 | #ifndef vma_mmu_pagesize | |
334 | unsigned long vma_mmu_pagesize(struct vm_area_struct *vma) | |
335 | { | |
336 | return vma_kernel_pagesize(vma); | |
337 | } | |
338 | #endif | |
339 | ||
84afd99b AW |
340 | /* |
341 | * Flags for MAP_PRIVATE reservations. These are stored in the bottom | |
342 | * bits of the reservation map pointer, which are always clear due to | |
343 | * alignment. | |
344 | */ | |
345 | #define HPAGE_RESV_OWNER (1UL << 0) | |
346 | #define HPAGE_RESV_UNMAPPED (1UL << 1) | |
04f2cbe3 | 347 | #define HPAGE_RESV_MASK (HPAGE_RESV_OWNER | HPAGE_RESV_UNMAPPED) |
84afd99b | 348 | |
a1e78772 MG |
349 | /* |
350 | * These helpers are used to track how many pages are reserved for | |
351 | * faults in a MAP_PRIVATE mapping. Only the process that called mmap() | |
352 | * is guaranteed to have their future faults succeed. | |
353 | * | |
354 | * With the exception of reset_vma_resv_huge_pages() which is called at fork(), | |
355 | * the reserve counters are updated with the hugetlb_lock held. It is safe | |
356 | * to reset the VMA at fork() time as it is not in use yet and there is no | |
357 | * chance of the global counters getting corrupted as a result of the values. | |
84afd99b AW |
358 | * |
359 | * The private mapping reservation is represented in a subtly different | |
360 | * manner to a shared mapping. A shared mapping has a region map associated | |
361 | * with the underlying file, this region map represents the backing file | |
362 | * pages which have ever had a reservation assigned which this persists even | |
363 | * after the page is instantiated. A private mapping has a region map | |
364 | * associated with the original mmap which is attached to all VMAs which | |
365 | * reference it, this region map represents those offsets which have consumed | |
366 | * reservation ie. where pages have been instantiated. | |
a1e78772 | 367 | */ |
e7c4b0bf AW |
368 | static unsigned long get_vma_private_data(struct vm_area_struct *vma) |
369 | { | |
370 | return (unsigned long)vma->vm_private_data; | |
371 | } | |
372 | ||
373 | static void set_vma_private_data(struct vm_area_struct *vma, | |
374 | unsigned long value) | |
375 | { | |
376 | vma->vm_private_data = (void *)value; | |
377 | } | |
378 | ||
84afd99b AW |
379 | struct resv_map { |
380 | struct kref refs; | |
381 | struct list_head regions; | |
382 | }; | |
383 | ||
2a4b3ded | 384 | static struct resv_map *resv_map_alloc(void) |
84afd99b AW |
385 | { |
386 | struct resv_map *resv_map = kmalloc(sizeof(*resv_map), GFP_KERNEL); | |
387 | if (!resv_map) | |
388 | return NULL; | |
389 | ||
390 | kref_init(&resv_map->refs); | |
391 | INIT_LIST_HEAD(&resv_map->regions); | |
392 | ||
393 | return resv_map; | |
394 | } | |
395 | ||
2a4b3ded | 396 | static void resv_map_release(struct kref *ref) |
84afd99b AW |
397 | { |
398 | struct resv_map *resv_map = container_of(ref, struct resv_map, refs); | |
399 | ||
400 | /* Clear out any active regions before we release the map. */ | |
401 | region_truncate(&resv_map->regions, 0); | |
402 | kfree(resv_map); | |
403 | } | |
404 | ||
405 | static struct resv_map *vma_resv_map(struct vm_area_struct *vma) | |
a1e78772 MG |
406 | { |
407 | VM_BUG_ON(!is_vm_hugetlb_page(vma)); | |
f83a275d | 408 | if (!(vma->vm_flags & VM_MAYSHARE)) |
84afd99b AW |
409 | return (struct resv_map *)(get_vma_private_data(vma) & |
410 | ~HPAGE_RESV_MASK); | |
2a4b3ded | 411 | return NULL; |
a1e78772 MG |
412 | } |
413 | ||
84afd99b | 414 | static void set_vma_resv_map(struct vm_area_struct *vma, struct resv_map *map) |
a1e78772 MG |
415 | { |
416 | VM_BUG_ON(!is_vm_hugetlb_page(vma)); | |
f83a275d | 417 | VM_BUG_ON(vma->vm_flags & VM_MAYSHARE); |
a1e78772 | 418 | |
84afd99b AW |
419 | set_vma_private_data(vma, (get_vma_private_data(vma) & |
420 | HPAGE_RESV_MASK) | (unsigned long)map); | |
04f2cbe3 MG |
421 | } |
422 | ||
423 | static void set_vma_resv_flags(struct vm_area_struct *vma, unsigned long flags) | |
424 | { | |
04f2cbe3 | 425 | VM_BUG_ON(!is_vm_hugetlb_page(vma)); |
f83a275d | 426 | VM_BUG_ON(vma->vm_flags & VM_MAYSHARE); |
e7c4b0bf AW |
427 | |
428 | set_vma_private_data(vma, get_vma_private_data(vma) | flags); | |
04f2cbe3 MG |
429 | } |
430 | ||
431 | static int is_vma_resv_set(struct vm_area_struct *vma, unsigned long flag) | |
432 | { | |
433 | VM_BUG_ON(!is_vm_hugetlb_page(vma)); | |
e7c4b0bf AW |
434 | |
435 | return (get_vma_private_data(vma) & flag) != 0; | |
a1e78772 MG |
436 | } |
437 | ||
438 | /* Decrement the reserved pages in the hugepage pool by one */ | |
a5516438 AK |
439 | static void decrement_hugepage_resv_vma(struct hstate *h, |
440 | struct vm_area_struct *vma) | |
a1e78772 | 441 | { |
c37f9fb1 AW |
442 | if (vma->vm_flags & VM_NORESERVE) |
443 | return; | |
444 | ||
f83a275d | 445 | if (vma->vm_flags & VM_MAYSHARE) { |
a1e78772 | 446 | /* Shared mappings always use reserves */ |
a5516438 | 447 | h->resv_huge_pages--; |
84afd99b | 448 | } else if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { |
a1e78772 MG |
449 | /* |
450 | * Only the process that called mmap() has reserves for | |
451 | * private mappings. | |
452 | */ | |
a5516438 | 453 | h->resv_huge_pages--; |
a1e78772 MG |
454 | } |
455 | } | |
456 | ||
04f2cbe3 | 457 | /* Reset counters to 0 and clear all HPAGE_RESV_* flags */ |
a1e78772 MG |
458 | void reset_vma_resv_huge_pages(struct vm_area_struct *vma) |
459 | { | |
460 | VM_BUG_ON(!is_vm_hugetlb_page(vma)); | |
f83a275d | 461 | if (!(vma->vm_flags & VM_MAYSHARE)) |
a1e78772 MG |
462 | vma->vm_private_data = (void *)0; |
463 | } | |
464 | ||
465 | /* Returns true if the VMA has associated reserve pages */ | |
7f09ca51 | 466 | static int vma_has_reserves(struct vm_area_struct *vma) |
a1e78772 | 467 | { |
f83a275d | 468 | if (vma->vm_flags & VM_MAYSHARE) |
7f09ca51 MG |
469 | return 1; |
470 | if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) | |
471 | return 1; | |
472 | return 0; | |
a1e78772 MG |
473 | } |
474 | ||
0ebabb41 NH |
475 | static void copy_gigantic_page(struct page *dst, struct page *src) |
476 | { | |
477 | int i; | |
478 | struct hstate *h = page_hstate(src); | |
479 | struct page *dst_base = dst; | |
480 | struct page *src_base = src; | |
481 | ||
482 | for (i = 0; i < pages_per_huge_page(h); ) { | |
483 | cond_resched(); | |
484 | copy_highpage(dst, src); | |
485 | ||
486 | i++; | |
487 | dst = mem_map_next(dst, dst_base, i); | |
488 | src = mem_map_next(src, src_base, i); | |
489 | } | |
490 | } | |
491 | ||
492 | void copy_huge_page(struct page *dst, struct page *src) | |
493 | { | |
494 | int i; | |
495 | struct hstate *h = page_hstate(src); | |
496 | ||
497 | if (unlikely(pages_per_huge_page(h) > MAX_ORDER_NR_PAGES)) { | |
498 | copy_gigantic_page(dst, src); | |
499 | return; | |
500 | } | |
501 | ||
502 | might_sleep(); | |
503 | for (i = 0; i < pages_per_huge_page(h); i++) { | |
504 | cond_resched(); | |
505 | copy_highpage(dst + i, src + i); | |
506 | } | |
507 | } | |
508 | ||
a5516438 | 509 | static void enqueue_huge_page(struct hstate *h, struct page *page) |
1da177e4 LT |
510 | { |
511 | int nid = page_to_nid(page); | |
0edaecfa | 512 | list_move(&page->lru, &h->hugepage_freelists[nid]); |
a5516438 AK |
513 | h->free_huge_pages++; |
514 | h->free_huge_pages_node[nid]++; | |
1da177e4 LT |
515 | } |
516 | ||
bf50bab2 NH |
517 | static struct page *dequeue_huge_page_node(struct hstate *h, int nid) |
518 | { | |
519 | struct page *page; | |
520 | ||
521 | if (list_empty(&h->hugepage_freelists[nid])) | |
522 | return NULL; | |
523 | page = list_entry(h->hugepage_freelists[nid].next, struct page, lru); | |
0edaecfa | 524 | list_move(&page->lru, &h->hugepage_activelist); |
a9869b83 | 525 | set_page_refcounted(page); |
bf50bab2 NH |
526 | h->free_huge_pages--; |
527 | h->free_huge_pages_node[nid]--; | |
528 | return page; | |
529 | } | |
530 | ||
a5516438 AK |
531 | static struct page *dequeue_huge_page_vma(struct hstate *h, |
532 | struct vm_area_struct *vma, | |
04f2cbe3 | 533 | unsigned long address, int avoid_reserve) |
1da177e4 | 534 | { |
b1c12cbc | 535 | struct page *page = NULL; |
480eccf9 | 536 | struct mempolicy *mpol; |
19770b32 | 537 | nodemask_t *nodemask; |
c0ff7453 | 538 | struct zonelist *zonelist; |
dd1a239f MG |
539 | struct zone *zone; |
540 | struct zoneref *z; | |
cc9a6c87 | 541 | unsigned int cpuset_mems_cookie; |
1da177e4 | 542 | |
cc9a6c87 MG |
543 | retry_cpuset: |
544 | cpuset_mems_cookie = get_mems_allowed(); | |
c0ff7453 MX |
545 | zonelist = huge_zonelist(vma, address, |
546 | htlb_alloc_mask, &mpol, &nodemask); | |
a1e78772 MG |
547 | /* |
548 | * A child process with MAP_PRIVATE mappings created by their parent | |
549 | * have no page reserves. This check ensures that reservations are | |
550 | * not "stolen". The child may still get SIGKILLed | |
551 | */ | |
7f09ca51 | 552 | if (!vma_has_reserves(vma) && |
a5516438 | 553 | h->free_huge_pages - h->resv_huge_pages == 0) |
c0ff7453 | 554 | goto err; |
a1e78772 | 555 | |
04f2cbe3 | 556 | /* If reserves cannot be used, ensure enough pages are in the pool */ |
a5516438 | 557 | if (avoid_reserve && h->free_huge_pages - h->resv_huge_pages == 0) |
6eab04a8 | 558 | goto err; |
04f2cbe3 | 559 | |
19770b32 MG |
560 | for_each_zone_zonelist_nodemask(zone, z, zonelist, |
561 | MAX_NR_ZONES - 1, nodemask) { | |
bf50bab2 NH |
562 | if (cpuset_zone_allowed_softwall(zone, htlb_alloc_mask)) { |
563 | page = dequeue_huge_page_node(h, zone_to_nid(zone)); | |
564 | if (page) { | |
565 | if (!avoid_reserve) | |
566 | decrement_hugepage_resv_vma(h, vma); | |
567 | break; | |
568 | } | |
3abf7afd | 569 | } |
1da177e4 | 570 | } |
cc9a6c87 | 571 | |
52cd3b07 | 572 | mpol_cond_put(mpol); |
cc9a6c87 MG |
573 | if (unlikely(!put_mems_allowed(cpuset_mems_cookie) && !page)) |
574 | goto retry_cpuset; | |
1da177e4 | 575 | return page; |
cc9a6c87 MG |
576 | |
577 | err: | |
578 | mpol_cond_put(mpol); | |
579 | return NULL; | |
1da177e4 LT |
580 | } |
581 | ||
a5516438 | 582 | static void update_and_free_page(struct hstate *h, struct page *page) |
6af2acb6 AL |
583 | { |
584 | int i; | |
a5516438 | 585 | |
18229df5 AW |
586 | VM_BUG_ON(h->order >= MAX_ORDER); |
587 | ||
a5516438 AK |
588 | h->nr_huge_pages--; |
589 | h->nr_huge_pages_node[page_to_nid(page)]--; | |
590 | for (i = 0; i < pages_per_huge_page(h); i++) { | |
32f84528 CF |
591 | page[i].flags &= ~(1 << PG_locked | 1 << PG_error | |
592 | 1 << PG_referenced | 1 << PG_dirty | | |
593 | 1 << PG_active | 1 << PG_reserved | | |
594 | 1 << PG_private | 1 << PG_writeback); | |
6af2acb6 | 595 | } |
9dd540e2 | 596 | VM_BUG_ON(hugetlb_cgroup_from_page(page)); |
6af2acb6 AL |
597 | set_compound_page_dtor(page, NULL); |
598 | set_page_refcounted(page); | |
7f2e9525 | 599 | arch_release_hugepage(page); |
a5516438 | 600 | __free_pages(page, huge_page_order(h)); |
6af2acb6 AL |
601 | } |
602 | ||
e5ff2159 AK |
603 | struct hstate *size_to_hstate(unsigned long size) |
604 | { | |
605 | struct hstate *h; | |
606 | ||
607 | for_each_hstate(h) { | |
608 | if (huge_page_size(h) == size) | |
609 | return h; | |
610 | } | |
611 | return NULL; | |
612 | } | |
613 | ||
27a85ef1 DG |
614 | static void free_huge_page(struct page *page) |
615 | { | |
a5516438 AK |
616 | /* |
617 | * Can't pass hstate in here because it is called from the | |
618 | * compound page destructor. | |
619 | */ | |
e5ff2159 | 620 | struct hstate *h = page_hstate(page); |
7893d1d5 | 621 | int nid = page_to_nid(page); |
90481622 DG |
622 | struct hugepage_subpool *spool = |
623 | (struct hugepage_subpool *)page_private(page); | |
27a85ef1 | 624 | |
e5df70ab | 625 | set_page_private(page, 0); |
23be7468 | 626 | page->mapping = NULL; |
7893d1d5 | 627 | BUG_ON(page_count(page)); |
0fe6e20b | 628 | BUG_ON(page_mapcount(page)); |
27a85ef1 DG |
629 | |
630 | spin_lock(&hugetlb_lock); | |
6d76dcf4 AK |
631 | hugetlb_cgroup_uncharge_page(hstate_index(h), |
632 | pages_per_huge_page(h), page); | |
aa888a74 | 633 | if (h->surplus_huge_pages_node[nid] && huge_page_order(h) < MAX_ORDER) { |
0edaecfa AK |
634 | /* remove the page from active list */ |
635 | list_del(&page->lru); | |
a5516438 AK |
636 | update_and_free_page(h, page); |
637 | h->surplus_huge_pages--; | |
638 | h->surplus_huge_pages_node[nid]--; | |
7893d1d5 | 639 | } else { |
a5516438 | 640 | enqueue_huge_page(h, page); |
7893d1d5 | 641 | } |
27a85ef1 | 642 | spin_unlock(&hugetlb_lock); |
90481622 | 643 | hugepage_subpool_put_pages(spool, 1); |
27a85ef1 DG |
644 | } |
645 | ||
a5516438 | 646 | static void prep_new_huge_page(struct hstate *h, struct page *page, int nid) |
b7ba30c6 | 647 | { |
0edaecfa | 648 | INIT_LIST_HEAD(&page->lru); |
b7ba30c6 AK |
649 | set_compound_page_dtor(page, free_huge_page); |
650 | spin_lock(&hugetlb_lock); | |
9dd540e2 | 651 | set_hugetlb_cgroup(page, NULL); |
a5516438 AK |
652 | h->nr_huge_pages++; |
653 | h->nr_huge_pages_node[nid]++; | |
b7ba30c6 AK |
654 | spin_unlock(&hugetlb_lock); |
655 | put_page(page); /* free it into the hugepage allocator */ | |
656 | } | |
657 | ||
20a0307c WF |
658 | static void prep_compound_gigantic_page(struct page *page, unsigned long order) |
659 | { | |
660 | int i; | |
661 | int nr_pages = 1 << order; | |
662 | struct page *p = page + 1; | |
663 | ||
664 | /* we rely on prep_new_huge_page to set the destructor */ | |
665 | set_compound_order(page, order); | |
666 | __SetPageHead(page); | |
667 | for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) { | |
668 | __SetPageTail(p); | |
58a84aa9 | 669 | set_page_count(p, 0); |
20a0307c WF |
670 | p->first_page = page; |
671 | } | |
672 | } | |
673 | ||
674 | int PageHuge(struct page *page) | |
675 | { | |
676 | compound_page_dtor *dtor; | |
677 | ||
678 | if (!PageCompound(page)) | |
679 | return 0; | |
680 | ||
681 | page = compound_head(page); | |
682 | dtor = get_compound_page_dtor(page); | |
683 | ||
684 | return dtor == free_huge_page; | |
685 | } | |
43131e14 NH |
686 | EXPORT_SYMBOL_GPL(PageHuge); |
687 | ||
a5516438 | 688 | static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid) |
1da177e4 | 689 | { |
1da177e4 | 690 | struct page *page; |
f96efd58 | 691 | |
aa888a74 AK |
692 | if (h->order >= MAX_ORDER) |
693 | return NULL; | |
694 | ||
6484eb3e | 695 | page = alloc_pages_exact_node(nid, |
551883ae NA |
696 | htlb_alloc_mask|__GFP_COMP|__GFP_THISNODE| |
697 | __GFP_REPEAT|__GFP_NOWARN, | |
a5516438 | 698 | huge_page_order(h)); |
1da177e4 | 699 | if (page) { |
7f2e9525 | 700 | if (arch_prepare_hugepage(page)) { |
caff3a2c | 701 | __free_pages(page, huge_page_order(h)); |
7b8ee84d | 702 | return NULL; |
7f2e9525 | 703 | } |
a5516438 | 704 | prep_new_huge_page(h, page, nid); |
1da177e4 | 705 | } |
63b4613c NA |
706 | |
707 | return page; | |
708 | } | |
709 | ||
9a76db09 | 710 | /* |
6ae11b27 LS |
711 | * common helper functions for hstate_next_node_to_{alloc|free}. |
712 | * We may have allocated or freed a huge page based on a different | |
713 | * nodes_allowed previously, so h->next_node_to_{alloc|free} might | |
714 | * be outside of *nodes_allowed. Ensure that we use an allowed | |
715 | * node for alloc or free. | |
9a76db09 | 716 | */ |
6ae11b27 | 717 | static int next_node_allowed(int nid, nodemask_t *nodes_allowed) |
9a76db09 | 718 | { |
6ae11b27 | 719 | nid = next_node(nid, *nodes_allowed); |
9a76db09 | 720 | if (nid == MAX_NUMNODES) |
6ae11b27 | 721 | nid = first_node(*nodes_allowed); |
9a76db09 LS |
722 | VM_BUG_ON(nid >= MAX_NUMNODES); |
723 | ||
724 | return nid; | |
725 | } | |
726 | ||
6ae11b27 LS |
727 | static int get_valid_node_allowed(int nid, nodemask_t *nodes_allowed) |
728 | { | |
729 | if (!node_isset(nid, *nodes_allowed)) | |
730 | nid = next_node_allowed(nid, nodes_allowed); | |
731 | return nid; | |
732 | } | |
733 | ||
5ced66c9 | 734 | /* |
6ae11b27 LS |
735 | * returns the previously saved node ["this node"] from which to |
736 | * allocate a persistent huge page for the pool and advance the | |
737 | * next node from which to allocate, handling wrap at end of node | |
738 | * mask. | |
5ced66c9 | 739 | */ |
6ae11b27 LS |
740 | static int hstate_next_node_to_alloc(struct hstate *h, |
741 | nodemask_t *nodes_allowed) | |
5ced66c9 | 742 | { |
6ae11b27 LS |
743 | int nid; |
744 | ||
745 | VM_BUG_ON(!nodes_allowed); | |
746 | ||
747 | nid = get_valid_node_allowed(h->next_nid_to_alloc, nodes_allowed); | |
748 | h->next_nid_to_alloc = next_node_allowed(nid, nodes_allowed); | |
9a76db09 | 749 | |
9a76db09 | 750 | return nid; |
5ced66c9 AK |
751 | } |
752 | ||
6ae11b27 | 753 | static int alloc_fresh_huge_page(struct hstate *h, nodemask_t *nodes_allowed) |
63b4613c NA |
754 | { |
755 | struct page *page; | |
756 | int start_nid; | |
757 | int next_nid; | |
758 | int ret = 0; | |
759 | ||
6ae11b27 | 760 | start_nid = hstate_next_node_to_alloc(h, nodes_allowed); |
e8c5c824 | 761 | next_nid = start_nid; |
63b4613c NA |
762 | |
763 | do { | |
e8c5c824 | 764 | page = alloc_fresh_huge_page_node(h, next_nid); |
9a76db09 | 765 | if (page) { |
63b4613c | 766 | ret = 1; |
9a76db09 LS |
767 | break; |
768 | } | |
6ae11b27 | 769 | next_nid = hstate_next_node_to_alloc(h, nodes_allowed); |
9a76db09 | 770 | } while (next_nid != start_nid); |
63b4613c | 771 | |
3b116300 AL |
772 | if (ret) |
773 | count_vm_event(HTLB_BUDDY_PGALLOC); | |
774 | else | |
775 | count_vm_event(HTLB_BUDDY_PGALLOC_FAIL); | |
776 | ||
63b4613c | 777 | return ret; |
1da177e4 LT |
778 | } |
779 | ||
e8c5c824 | 780 | /* |
6ae11b27 LS |
781 | * helper for free_pool_huge_page() - return the previously saved |
782 | * node ["this node"] from which to free a huge page. Advance the | |
783 | * next node id whether or not we find a free huge page to free so | |
784 | * that the next attempt to free addresses the next node. | |
e8c5c824 | 785 | */ |
6ae11b27 | 786 | static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed) |
e8c5c824 | 787 | { |
6ae11b27 LS |
788 | int nid; |
789 | ||
790 | VM_BUG_ON(!nodes_allowed); | |
791 | ||
792 | nid = get_valid_node_allowed(h->next_nid_to_free, nodes_allowed); | |
793 | h->next_nid_to_free = next_node_allowed(nid, nodes_allowed); | |
9a76db09 | 794 | |
9a76db09 | 795 | return nid; |
e8c5c824 LS |
796 | } |
797 | ||
798 | /* | |
799 | * Free huge page from pool from next node to free. | |
800 | * Attempt to keep persistent huge pages more or less | |
801 | * balanced over allowed nodes. | |
802 | * Called with hugetlb_lock locked. | |
803 | */ | |
6ae11b27 LS |
804 | static int free_pool_huge_page(struct hstate *h, nodemask_t *nodes_allowed, |
805 | bool acct_surplus) | |
e8c5c824 LS |
806 | { |
807 | int start_nid; | |
808 | int next_nid; | |
809 | int ret = 0; | |
810 | ||
6ae11b27 | 811 | start_nid = hstate_next_node_to_free(h, nodes_allowed); |
e8c5c824 LS |
812 | next_nid = start_nid; |
813 | ||
814 | do { | |
685f3457 LS |
815 | /* |
816 | * If we're returning unused surplus pages, only examine | |
817 | * nodes with surplus pages. | |
818 | */ | |
819 | if ((!acct_surplus || h->surplus_huge_pages_node[next_nid]) && | |
820 | !list_empty(&h->hugepage_freelists[next_nid])) { | |
e8c5c824 LS |
821 | struct page *page = |
822 | list_entry(h->hugepage_freelists[next_nid].next, | |
823 | struct page, lru); | |
824 | list_del(&page->lru); | |
825 | h->free_huge_pages--; | |
826 | h->free_huge_pages_node[next_nid]--; | |
685f3457 LS |
827 | if (acct_surplus) { |
828 | h->surplus_huge_pages--; | |
829 | h->surplus_huge_pages_node[next_nid]--; | |
830 | } | |
e8c5c824 LS |
831 | update_and_free_page(h, page); |
832 | ret = 1; | |
9a76db09 | 833 | break; |
e8c5c824 | 834 | } |
6ae11b27 | 835 | next_nid = hstate_next_node_to_free(h, nodes_allowed); |
9a76db09 | 836 | } while (next_nid != start_nid); |
e8c5c824 LS |
837 | |
838 | return ret; | |
839 | } | |
840 | ||
bf50bab2 | 841 | static struct page *alloc_buddy_huge_page(struct hstate *h, int nid) |
7893d1d5 AL |
842 | { |
843 | struct page *page; | |
bf50bab2 | 844 | unsigned int r_nid; |
7893d1d5 | 845 | |
aa888a74 AK |
846 | if (h->order >= MAX_ORDER) |
847 | return NULL; | |
848 | ||
d1c3fb1f NA |
849 | /* |
850 | * Assume we will successfully allocate the surplus page to | |
851 | * prevent racing processes from causing the surplus to exceed | |
852 | * overcommit | |
853 | * | |
854 | * This however introduces a different race, where a process B | |
855 | * tries to grow the static hugepage pool while alloc_pages() is | |
856 | * called by process A. B will only examine the per-node | |
857 | * counters in determining if surplus huge pages can be | |
858 | * converted to normal huge pages in adjust_pool_surplus(). A | |
859 | * won't be able to increment the per-node counter, until the | |
860 | * lock is dropped by B, but B doesn't drop hugetlb_lock until | |
861 | * no more huge pages can be converted from surplus to normal | |
862 | * state (and doesn't try to convert again). Thus, we have a | |
863 | * case where a surplus huge page exists, the pool is grown, and | |
864 | * the surplus huge page still exists after, even though it | |
865 | * should just have been converted to a normal huge page. This | |
866 | * does not leak memory, though, as the hugepage will be freed | |
867 | * once it is out of use. It also does not allow the counters to | |
868 | * go out of whack in adjust_pool_surplus() as we don't modify | |
869 | * the node values until we've gotten the hugepage and only the | |
870 | * per-node value is checked there. | |
871 | */ | |
872 | spin_lock(&hugetlb_lock); | |
a5516438 | 873 | if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages) { |
d1c3fb1f NA |
874 | spin_unlock(&hugetlb_lock); |
875 | return NULL; | |
876 | } else { | |
a5516438 AK |
877 | h->nr_huge_pages++; |
878 | h->surplus_huge_pages++; | |
d1c3fb1f NA |
879 | } |
880 | spin_unlock(&hugetlb_lock); | |
881 | ||
bf50bab2 NH |
882 | if (nid == NUMA_NO_NODE) |
883 | page = alloc_pages(htlb_alloc_mask|__GFP_COMP| | |
884 | __GFP_REPEAT|__GFP_NOWARN, | |
885 | huge_page_order(h)); | |
886 | else | |
887 | page = alloc_pages_exact_node(nid, | |
888 | htlb_alloc_mask|__GFP_COMP|__GFP_THISNODE| | |
889 | __GFP_REPEAT|__GFP_NOWARN, huge_page_order(h)); | |
d1c3fb1f | 890 | |
caff3a2c GS |
891 | if (page && arch_prepare_hugepage(page)) { |
892 | __free_pages(page, huge_page_order(h)); | |
ea5768c7 | 893 | page = NULL; |
caff3a2c GS |
894 | } |
895 | ||
d1c3fb1f | 896 | spin_lock(&hugetlb_lock); |
7893d1d5 | 897 | if (page) { |
0edaecfa | 898 | INIT_LIST_HEAD(&page->lru); |
bf50bab2 | 899 | r_nid = page_to_nid(page); |
7893d1d5 | 900 | set_compound_page_dtor(page, free_huge_page); |
9dd540e2 | 901 | set_hugetlb_cgroup(page, NULL); |
d1c3fb1f NA |
902 | /* |
903 | * We incremented the global counters already | |
904 | */ | |
bf50bab2 NH |
905 | h->nr_huge_pages_node[r_nid]++; |
906 | h->surplus_huge_pages_node[r_nid]++; | |
3b116300 | 907 | __count_vm_event(HTLB_BUDDY_PGALLOC); |
d1c3fb1f | 908 | } else { |
a5516438 AK |
909 | h->nr_huge_pages--; |
910 | h->surplus_huge_pages--; | |
3b116300 | 911 | __count_vm_event(HTLB_BUDDY_PGALLOC_FAIL); |
7893d1d5 | 912 | } |
d1c3fb1f | 913 | spin_unlock(&hugetlb_lock); |
7893d1d5 AL |
914 | |
915 | return page; | |
916 | } | |
917 | ||
bf50bab2 NH |
918 | /* |
919 | * This allocation function is useful in the context where vma is irrelevant. | |
920 | * E.g. soft-offlining uses this function because it only cares physical | |
921 | * address of error page. | |
922 | */ | |
923 | struct page *alloc_huge_page_node(struct hstate *h, int nid) | |
924 | { | |
925 | struct page *page; | |
926 | ||
927 | spin_lock(&hugetlb_lock); | |
928 | page = dequeue_huge_page_node(h, nid); | |
929 | spin_unlock(&hugetlb_lock); | |
930 | ||
94ae8ba7 | 931 | if (!page) |
bf50bab2 NH |
932 | page = alloc_buddy_huge_page(h, nid); |
933 | ||
934 | return page; | |
935 | } | |
936 | ||
e4e574b7 | 937 | /* |
25985edc | 938 | * Increase the hugetlb pool such that it can accommodate a reservation |
e4e574b7 AL |
939 | * of size 'delta'. |
940 | */ | |
a5516438 | 941 | static int gather_surplus_pages(struct hstate *h, int delta) |
e4e574b7 AL |
942 | { |
943 | struct list_head surplus_list; | |
944 | struct page *page, *tmp; | |
945 | int ret, i; | |
946 | int needed, allocated; | |
28073b02 | 947 | bool alloc_ok = true; |
e4e574b7 | 948 | |
a5516438 | 949 | needed = (h->resv_huge_pages + delta) - h->free_huge_pages; |
ac09b3a1 | 950 | if (needed <= 0) { |
a5516438 | 951 | h->resv_huge_pages += delta; |
e4e574b7 | 952 | return 0; |
ac09b3a1 | 953 | } |
e4e574b7 AL |
954 | |
955 | allocated = 0; | |
956 | INIT_LIST_HEAD(&surplus_list); | |
957 | ||
958 | ret = -ENOMEM; | |
959 | retry: | |
960 | spin_unlock(&hugetlb_lock); | |
961 | for (i = 0; i < needed; i++) { | |
bf50bab2 | 962 | page = alloc_buddy_huge_page(h, NUMA_NO_NODE); |
28073b02 HD |
963 | if (!page) { |
964 | alloc_ok = false; | |
965 | break; | |
966 | } | |
e4e574b7 AL |
967 | list_add(&page->lru, &surplus_list); |
968 | } | |
28073b02 | 969 | allocated += i; |
e4e574b7 AL |
970 | |
971 | /* | |
972 | * After retaking hugetlb_lock, we need to recalculate 'needed' | |
973 | * because either resv_huge_pages or free_huge_pages may have changed. | |
974 | */ | |
975 | spin_lock(&hugetlb_lock); | |
a5516438 AK |
976 | needed = (h->resv_huge_pages + delta) - |
977 | (h->free_huge_pages + allocated); | |
28073b02 HD |
978 | if (needed > 0) { |
979 | if (alloc_ok) | |
980 | goto retry; | |
981 | /* | |
982 | * We were not able to allocate enough pages to | |
983 | * satisfy the entire reservation so we free what | |
984 | * we've allocated so far. | |
985 | */ | |
986 | goto free; | |
987 | } | |
e4e574b7 AL |
988 | /* |
989 | * The surplus_list now contains _at_least_ the number of extra pages | |
25985edc | 990 | * needed to accommodate the reservation. Add the appropriate number |
e4e574b7 | 991 | * of pages to the hugetlb pool and free the extras back to the buddy |
ac09b3a1 AL |
992 | * allocator. Commit the entire reservation here to prevent another |
993 | * process from stealing the pages as they are added to the pool but | |
994 | * before they are reserved. | |
e4e574b7 AL |
995 | */ |
996 | needed += allocated; | |
a5516438 | 997 | h->resv_huge_pages += delta; |
e4e574b7 | 998 | ret = 0; |
a9869b83 | 999 | |
19fc3f0a | 1000 | /* Free the needed pages to the hugetlb pool */ |
e4e574b7 | 1001 | list_for_each_entry_safe(page, tmp, &surplus_list, lru) { |
19fc3f0a AL |
1002 | if ((--needed) < 0) |
1003 | break; | |
a9869b83 NH |
1004 | /* |
1005 | * This page is now managed by the hugetlb allocator and has | |
1006 | * no users -- drop the buddy allocator's reference. | |
1007 | */ | |
1008 | put_page_testzero(page); | |
1009 | VM_BUG_ON(page_count(page)); | |
a5516438 | 1010 | enqueue_huge_page(h, page); |
19fc3f0a | 1011 | } |
28073b02 | 1012 | free: |
b0365c8d | 1013 | spin_unlock(&hugetlb_lock); |
19fc3f0a AL |
1014 | |
1015 | /* Free unnecessary surplus pages to the buddy allocator */ | |
1016 | if (!list_empty(&surplus_list)) { | |
19fc3f0a | 1017 | list_for_each_entry_safe(page, tmp, &surplus_list, lru) { |
a9869b83 | 1018 | put_page(page); |
af767cbd | 1019 | } |
e4e574b7 | 1020 | } |
a9869b83 | 1021 | spin_lock(&hugetlb_lock); |
e4e574b7 AL |
1022 | |
1023 | return ret; | |
1024 | } | |
1025 | ||
1026 | /* | |
1027 | * When releasing a hugetlb pool reservation, any surplus pages that were | |
1028 | * allocated to satisfy the reservation must be explicitly freed if they were | |
1029 | * never used. | |
685f3457 | 1030 | * Called with hugetlb_lock held. |
e4e574b7 | 1031 | */ |
a5516438 AK |
1032 | static void return_unused_surplus_pages(struct hstate *h, |
1033 | unsigned long unused_resv_pages) | |
e4e574b7 | 1034 | { |
e4e574b7 AL |
1035 | unsigned long nr_pages; |
1036 | ||
ac09b3a1 | 1037 | /* Uncommit the reservation */ |
a5516438 | 1038 | h->resv_huge_pages -= unused_resv_pages; |
ac09b3a1 | 1039 | |
aa888a74 AK |
1040 | /* Cannot return gigantic pages currently */ |
1041 | if (h->order >= MAX_ORDER) | |
1042 | return; | |
1043 | ||
a5516438 | 1044 | nr_pages = min(unused_resv_pages, h->surplus_huge_pages); |
e4e574b7 | 1045 | |
685f3457 LS |
1046 | /* |
1047 | * We want to release as many surplus pages as possible, spread | |
9b5e5d0f LS |
1048 | * evenly across all nodes with memory. Iterate across these nodes |
1049 | * until we can no longer free unreserved surplus pages. This occurs | |
1050 | * when the nodes with surplus pages have no free pages. | |
1051 | * free_pool_huge_page() will balance the the freed pages across the | |
1052 | * on-line nodes with memory and will handle the hstate accounting. | |
685f3457 LS |
1053 | */ |
1054 | while (nr_pages--) { | |
9b5e5d0f | 1055 | if (!free_pool_huge_page(h, &node_states[N_HIGH_MEMORY], 1)) |
685f3457 | 1056 | break; |
e4e574b7 AL |
1057 | } |
1058 | } | |
1059 | ||
c37f9fb1 AW |
1060 | /* |
1061 | * Determine if the huge page at addr within the vma has an associated | |
1062 | * reservation. Where it does not we will need to logically increase | |
90481622 DG |
1063 | * reservation and actually increase subpool usage before an allocation |
1064 | * can occur. Where any new reservation would be required the | |
1065 | * reservation change is prepared, but not committed. Once the page | |
1066 | * has been allocated from the subpool and instantiated the change should | |
1067 | * be committed via vma_commit_reservation. No action is required on | |
1068 | * failure. | |
c37f9fb1 | 1069 | */ |
e2f17d94 | 1070 | static long vma_needs_reservation(struct hstate *h, |
a5516438 | 1071 | struct vm_area_struct *vma, unsigned long addr) |
c37f9fb1 AW |
1072 | { |
1073 | struct address_space *mapping = vma->vm_file->f_mapping; | |
1074 | struct inode *inode = mapping->host; | |
1075 | ||
f83a275d | 1076 | if (vma->vm_flags & VM_MAYSHARE) { |
a5516438 | 1077 | pgoff_t idx = vma_hugecache_offset(h, vma, addr); |
c37f9fb1 AW |
1078 | return region_chg(&inode->i_mapping->private_list, |
1079 | idx, idx + 1); | |
1080 | ||
84afd99b AW |
1081 | } else if (!is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { |
1082 | return 1; | |
c37f9fb1 | 1083 | |
84afd99b | 1084 | } else { |
e2f17d94 | 1085 | long err; |
a5516438 | 1086 | pgoff_t idx = vma_hugecache_offset(h, vma, addr); |
84afd99b AW |
1087 | struct resv_map *reservations = vma_resv_map(vma); |
1088 | ||
1089 | err = region_chg(&reservations->regions, idx, idx + 1); | |
1090 | if (err < 0) | |
1091 | return err; | |
1092 | return 0; | |
1093 | } | |
c37f9fb1 | 1094 | } |
a5516438 AK |
1095 | static void vma_commit_reservation(struct hstate *h, |
1096 | struct vm_area_struct *vma, unsigned long addr) | |
c37f9fb1 AW |
1097 | { |
1098 | struct address_space *mapping = vma->vm_file->f_mapping; | |
1099 | struct inode *inode = mapping->host; | |
1100 | ||
f83a275d | 1101 | if (vma->vm_flags & VM_MAYSHARE) { |
a5516438 | 1102 | pgoff_t idx = vma_hugecache_offset(h, vma, addr); |
c37f9fb1 | 1103 | region_add(&inode->i_mapping->private_list, idx, idx + 1); |
84afd99b AW |
1104 | |
1105 | } else if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { | |
a5516438 | 1106 | pgoff_t idx = vma_hugecache_offset(h, vma, addr); |
84afd99b AW |
1107 | struct resv_map *reservations = vma_resv_map(vma); |
1108 | ||
1109 | /* Mark this page used in the map. */ | |
1110 | region_add(&reservations->regions, idx, idx + 1); | |
c37f9fb1 AW |
1111 | } |
1112 | } | |
1113 | ||
a1e78772 | 1114 | static struct page *alloc_huge_page(struct vm_area_struct *vma, |
04f2cbe3 | 1115 | unsigned long addr, int avoid_reserve) |
1da177e4 | 1116 | { |
90481622 | 1117 | struct hugepage_subpool *spool = subpool_vma(vma); |
a5516438 | 1118 | struct hstate *h = hstate_vma(vma); |
348ea204 | 1119 | struct page *page; |
e2f17d94 | 1120 | long chg; |
6d76dcf4 AK |
1121 | int ret, idx; |
1122 | struct hugetlb_cgroup *h_cg; | |
a1e78772 | 1123 | |
6d76dcf4 | 1124 | idx = hstate_index(h); |
a1e78772 | 1125 | /* |
90481622 DG |
1126 | * Processes that did not create the mapping will have no |
1127 | * reserves and will not have accounted against subpool | |
1128 | * limit. Check that the subpool limit can be made before | |
1129 | * satisfying the allocation MAP_NORESERVE mappings may also | |
1130 | * need pages and subpool limit allocated allocated if no reserve | |
1131 | * mapping overlaps. | |
a1e78772 | 1132 | */ |
a5516438 | 1133 | chg = vma_needs_reservation(h, vma, addr); |
c37f9fb1 | 1134 | if (chg < 0) |
76dcee75 | 1135 | return ERR_PTR(-ENOMEM); |
c37f9fb1 | 1136 | if (chg) |
90481622 | 1137 | if (hugepage_subpool_get_pages(spool, chg)) |
76dcee75 | 1138 | return ERR_PTR(-ENOSPC); |
1da177e4 | 1139 | |
6d76dcf4 AK |
1140 | ret = hugetlb_cgroup_charge_cgroup(idx, pages_per_huge_page(h), &h_cg); |
1141 | if (ret) { | |
1142 | hugepage_subpool_put_pages(spool, chg); | |
1143 | return ERR_PTR(-ENOSPC); | |
1144 | } | |
1da177e4 | 1145 | spin_lock(&hugetlb_lock); |
a5516438 | 1146 | page = dequeue_huge_page_vma(h, vma, addr, avoid_reserve); |
94ae8ba7 AK |
1147 | if (page) { |
1148 | /* update page cgroup details */ | |
1149 | hugetlb_cgroup_commit_charge(idx, pages_per_huge_page(h), | |
1150 | h_cg, page); | |
1151 | spin_unlock(&hugetlb_lock); | |
1152 | } else { | |
1153 | spin_unlock(&hugetlb_lock); | |
bf50bab2 | 1154 | page = alloc_buddy_huge_page(h, NUMA_NO_NODE); |
68842c9b | 1155 | if (!page) { |
6d76dcf4 AK |
1156 | hugetlb_cgroup_uncharge_cgroup(idx, |
1157 | pages_per_huge_page(h), | |
1158 | h_cg); | |
90481622 | 1159 | hugepage_subpool_put_pages(spool, chg); |
76dcee75 | 1160 | return ERR_PTR(-ENOSPC); |
68842c9b | 1161 | } |
79dbb236 | 1162 | spin_lock(&hugetlb_lock); |
94ae8ba7 AK |
1163 | hugetlb_cgroup_commit_charge(idx, pages_per_huge_page(h), |
1164 | h_cg, page); | |
79dbb236 AK |
1165 | list_move(&page->lru, &h->hugepage_activelist); |
1166 | spin_unlock(&hugetlb_lock); | |
68842c9b | 1167 | } |
348ea204 | 1168 | |
90481622 | 1169 | set_page_private(page, (unsigned long)spool); |
90d8b7e6 | 1170 | |
a5516438 | 1171 | vma_commit_reservation(h, vma, addr); |
90d8b7e6 | 1172 | return page; |
b45b5bd6 DG |
1173 | } |
1174 | ||
91f47662 | 1175 | int __weak alloc_bootmem_huge_page(struct hstate *h) |
aa888a74 AK |
1176 | { |
1177 | struct huge_bootmem_page *m; | |
9b5e5d0f | 1178 | int nr_nodes = nodes_weight(node_states[N_HIGH_MEMORY]); |
aa888a74 AK |
1179 | |
1180 | while (nr_nodes) { | |
1181 | void *addr; | |
1182 | ||
1183 | addr = __alloc_bootmem_node_nopanic( | |
6ae11b27 | 1184 | NODE_DATA(hstate_next_node_to_alloc(h, |
9b5e5d0f | 1185 | &node_states[N_HIGH_MEMORY])), |
aa888a74 AK |
1186 | huge_page_size(h), huge_page_size(h), 0); |
1187 | ||
1188 | if (addr) { | |
1189 | /* | |
1190 | * Use the beginning of the huge page to store the | |
1191 | * huge_bootmem_page struct (until gather_bootmem | |
1192 | * puts them into the mem_map). | |
1193 | */ | |
1194 | m = addr; | |
91f47662 | 1195 | goto found; |
aa888a74 | 1196 | } |
aa888a74 AK |
1197 | nr_nodes--; |
1198 | } | |
1199 | return 0; | |
1200 | ||
1201 | found: | |
1202 | BUG_ON((unsigned long)virt_to_phys(m) & (huge_page_size(h) - 1)); | |
1203 | /* Put them into a private list first because mem_map is not up yet */ | |
1204 | list_add(&m->list, &huge_boot_pages); | |
1205 | m->hstate = h; | |
1206 | return 1; | |
1207 | } | |
1208 | ||
18229df5 AW |
1209 | static void prep_compound_huge_page(struct page *page, int order) |
1210 | { | |
1211 | if (unlikely(order > (MAX_ORDER - 1))) | |
1212 | prep_compound_gigantic_page(page, order); | |
1213 | else | |
1214 | prep_compound_page(page, order); | |
1215 | } | |
1216 | ||
aa888a74 AK |
1217 | /* Put bootmem huge pages into the standard lists after mem_map is up */ |
1218 | static void __init gather_bootmem_prealloc(void) | |
1219 | { | |
1220 | struct huge_bootmem_page *m; | |
1221 | ||
1222 | list_for_each_entry(m, &huge_boot_pages, list) { | |
aa888a74 | 1223 | struct hstate *h = m->hstate; |
ee8f248d BB |
1224 | struct page *page; |
1225 | ||
1226 | #ifdef CONFIG_HIGHMEM | |
1227 | page = pfn_to_page(m->phys >> PAGE_SHIFT); | |
1228 | free_bootmem_late((unsigned long)m, | |
1229 | sizeof(struct huge_bootmem_page)); | |
1230 | #else | |
1231 | page = virt_to_page(m); | |
1232 | #endif | |
aa888a74 AK |
1233 | __ClearPageReserved(page); |
1234 | WARN_ON(page_count(page) != 1); | |
18229df5 | 1235 | prep_compound_huge_page(page, h->order); |
aa888a74 | 1236 | prep_new_huge_page(h, page, page_to_nid(page)); |
b0320c7b RA |
1237 | /* |
1238 | * If we had gigantic hugepages allocated at boot time, we need | |
1239 | * to restore the 'stolen' pages to totalram_pages in order to | |
1240 | * fix confusing memory reports from free(1) and another | |
1241 | * side-effects, like CommitLimit going negative. | |
1242 | */ | |
1243 | if (h->order > (MAX_ORDER - 1)) | |
1244 | totalram_pages += 1 << h->order; | |
aa888a74 AK |
1245 | } |
1246 | } | |
1247 | ||
8faa8b07 | 1248 | static void __init hugetlb_hstate_alloc_pages(struct hstate *h) |
1da177e4 LT |
1249 | { |
1250 | unsigned long i; | |
a5516438 | 1251 | |
e5ff2159 | 1252 | for (i = 0; i < h->max_huge_pages; ++i) { |
aa888a74 AK |
1253 | if (h->order >= MAX_ORDER) { |
1254 | if (!alloc_bootmem_huge_page(h)) | |
1255 | break; | |
9b5e5d0f LS |
1256 | } else if (!alloc_fresh_huge_page(h, |
1257 | &node_states[N_HIGH_MEMORY])) | |
1da177e4 | 1258 | break; |
1da177e4 | 1259 | } |
8faa8b07 | 1260 | h->max_huge_pages = i; |
e5ff2159 AK |
1261 | } |
1262 | ||
1263 | static void __init hugetlb_init_hstates(void) | |
1264 | { | |
1265 | struct hstate *h; | |
1266 | ||
1267 | for_each_hstate(h) { | |
8faa8b07 AK |
1268 | /* oversize hugepages were init'ed in early boot */ |
1269 | if (h->order < MAX_ORDER) | |
1270 | hugetlb_hstate_alloc_pages(h); | |
e5ff2159 AK |
1271 | } |
1272 | } | |
1273 | ||
4abd32db AK |
1274 | static char * __init memfmt(char *buf, unsigned long n) |
1275 | { | |
1276 | if (n >= (1UL << 30)) | |
1277 | sprintf(buf, "%lu GB", n >> 30); | |
1278 | else if (n >= (1UL << 20)) | |
1279 | sprintf(buf, "%lu MB", n >> 20); | |
1280 | else | |
1281 | sprintf(buf, "%lu KB", n >> 10); | |
1282 | return buf; | |
1283 | } | |
1284 | ||
e5ff2159 AK |
1285 | static void __init report_hugepages(void) |
1286 | { | |
1287 | struct hstate *h; | |
1288 | ||
1289 | for_each_hstate(h) { | |
4abd32db AK |
1290 | char buf[32]; |
1291 | printk(KERN_INFO "HugeTLB registered %s page size, " | |
1292 | "pre-allocated %ld pages\n", | |
1293 | memfmt(buf, huge_page_size(h)), | |
1294 | h->free_huge_pages); | |
e5ff2159 AK |
1295 | } |
1296 | } | |
1297 | ||
1da177e4 | 1298 | #ifdef CONFIG_HIGHMEM |
6ae11b27 LS |
1299 | static void try_to_free_low(struct hstate *h, unsigned long count, |
1300 | nodemask_t *nodes_allowed) | |
1da177e4 | 1301 | { |
4415cc8d CL |
1302 | int i; |
1303 | ||
aa888a74 AK |
1304 | if (h->order >= MAX_ORDER) |
1305 | return; | |
1306 | ||
6ae11b27 | 1307 | for_each_node_mask(i, *nodes_allowed) { |
1da177e4 | 1308 | struct page *page, *next; |
a5516438 AK |
1309 | struct list_head *freel = &h->hugepage_freelists[i]; |
1310 | list_for_each_entry_safe(page, next, freel, lru) { | |
1311 | if (count >= h->nr_huge_pages) | |
6b0c880d | 1312 | return; |
1da177e4 LT |
1313 | if (PageHighMem(page)) |
1314 | continue; | |
1315 | list_del(&page->lru); | |
e5ff2159 | 1316 | update_and_free_page(h, page); |
a5516438 AK |
1317 | h->free_huge_pages--; |
1318 | h->free_huge_pages_node[page_to_nid(page)]--; | |
1da177e4 LT |
1319 | } |
1320 | } | |
1321 | } | |
1322 | #else | |
6ae11b27 LS |
1323 | static inline void try_to_free_low(struct hstate *h, unsigned long count, |
1324 | nodemask_t *nodes_allowed) | |
1da177e4 LT |
1325 | { |
1326 | } | |
1327 | #endif | |
1328 | ||
20a0307c WF |
1329 | /* |
1330 | * Increment or decrement surplus_huge_pages. Keep node-specific counters | |
1331 | * balanced by operating on them in a round-robin fashion. | |
1332 | * Returns 1 if an adjustment was made. | |
1333 | */ | |
6ae11b27 LS |
1334 | static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed, |
1335 | int delta) | |
20a0307c | 1336 | { |
e8c5c824 | 1337 | int start_nid, next_nid; |
20a0307c WF |
1338 | int ret = 0; |
1339 | ||
1340 | VM_BUG_ON(delta != -1 && delta != 1); | |
20a0307c | 1341 | |
e8c5c824 | 1342 | if (delta < 0) |
6ae11b27 | 1343 | start_nid = hstate_next_node_to_alloc(h, nodes_allowed); |
e8c5c824 | 1344 | else |
6ae11b27 | 1345 | start_nid = hstate_next_node_to_free(h, nodes_allowed); |
e8c5c824 LS |
1346 | next_nid = start_nid; |
1347 | ||
1348 | do { | |
1349 | int nid = next_nid; | |
1350 | if (delta < 0) { | |
e8c5c824 LS |
1351 | /* |
1352 | * To shrink on this node, there must be a surplus page | |
1353 | */ | |
9a76db09 | 1354 | if (!h->surplus_huge_pages_node[nid]) { |
6ae11b27 LS |
1355 | next_nid = hstate_next_node_to_alloc(h, |
1356 | nodes_allowed); | |
e8c5c824 | 1357 | continue; |
9a76db09 | 1358 | } |
e8c5c824 LS |
1359 | } |
1360 | if (delta > 0) { | |
e8c5c824 LS |
1361 | /* |
1362 | * Surplus cannot exceed the total number of pages | |
1363 | */ | |
1364 | if (h->surplus_huge_pages_node[nid] >= | |
9a76db09 | 1365 | h->nr_huge_pages_node[nid]) { |
6ae11b27 LS |
1366 | next_nid = hstate_next_node_to_free(h, |
1367 | nodes_allowed); | |
e8c5c824 | 1368 | continue; |
9a76db09 | 1369 | } |
e8c5c824 | 1370 | } |
20a0307c WF |
1371 | |
1372 | h->surplus_huge_pages += delta; | |
1373 | h->surplus_huge_pages_node[nid] += delta; | |
1374 | ret = 1; | |
1375 | break; | |
e8c5c824 | 1376 | } while (next_nid != start_nid); |
20a0307c | 1377 | |
20a0307c WF |
1378 | return ret; |
1379 | } | |
1380 | ||
a5516438 | 1381 | #define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages) |
6ae11b27 LS |
1382 | static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count, |
1383 | nodemask_t *nodes_allowed) | |
1da177e4 | 1384 | { |
7893d1d5 | 1385 | unsigned long min_count, ret; |
1da177e4 | 1386 | |
aa888a74 AK |
1387 | if (h->order >= MAX_ORDER) |
1388 | return h->max_huge_pages; | |
1389 | ||
7893d1d5 AL |
1390 | /* |
1391 | * Increase the pool size | |
1392 | * First take pages out of surplus state. Then make up the | |
1393 | * remaining difference by allocating fresh huge pages. | |
d1c3fb1f NA |
1394 | * |
1395 | * We might race with alloc_buddy_huge_page() here and be unable | |
1396 | * to convert a surplus huge page to a normal huge page. That is | |
1397 | * not critical, though, it just means the overall size of the | |
1398 | * pool might be one hugepage larger than it needs to be, but | |
1399 | * within all the constraints specified by the sysctls. | |
7893d1d5 | 1400 | */ |
1da177e4 | 1401 | spin_lock(&hugetlb_lock); |
a5516438 | 1402 | while (h->surplus_huge_pages && count > persistent_huge_pages(h)) { |
6ae11b27 | 1403 | if (!adjust_pool_surplus(h, nodes_allowed, -1)) |
7893d1d5 AL |
1404 | break; |
1405 | } | |
1406 | ||
a5516438 | 1407 | while (count > persistent_huge_pages(h)) { |
7893d1d5 AL |
1408 | /* |
1409 | * If this allocation races such that we no longer need the | |
1410 | * page, free_huge_page will handle it by freeing the page | |
1411 | * and reducing the surplus. | |
1412 | */ | |
1413 | spin_unlock(&hugetlb_lock); | |
6ae11b27 | 1414 | ret = alloc_fresh_huge_page(h, nodes_allowed); |
7893d1d5 AL |
1415 | spin_lock(&hugetlb_lock); |
1416 | if (!ret) | |
1417 | goto out; | |
1418 | ||
536240f2 MG |
1419 | /* Bail for signals. Probably ctrl-c from user */ |
1420 | if (signal_pending(current)) | |
1421 | goto out; | |
7893d1d5 | 1422 | } |
7893d1d5 AL |
1423 | |
1424 | /* | |
1425 | * Decrease the pool size | |
1426 | * First return free pages to the buddy allocator (being careful | |
1427 | * to keep enough around to satisfy reservations). Then place | |
1428 | * pages into surplus state as needed so the pool will shrink | |
1429 | * to the desired size as pages become free. | |
d1c3fb1f NA |
1430 | * |
1431 | * By placing pages into the surplus state independent of the | |
1432 | * overcommit value, we are allowing the surplus pool size to | |
1433 | * exceed overcommit. There are few sane options here. Since | |
1434 | * alloc_buddy_huge_page() is checking the global counter, | |
1435 | * though, we'll note that we're not allowed to exceed surplus | |
1436 | * and won't grow the pool anywhere else. Not until one of the | |
1437 | * sysctls are changed, or the surplus pages go out of use. | |
7893d1d5 | 1438 | */ |
a5516438 | 1439 | min_count = h->resv_huge_pages + h->nr_huge_pages - h->free_huge_pages; |
6b0c880d | 1440 | min_count = max(count, min_count); |
6ae11b27 | 1441 | try_to_free_low(h, min_count, nodes_allowed); |
a5516438 | 1442 | while (min_count < persistent_huge_pages(h)) { |
6ae11b27 | 1443 | if (!free_pool_huge_page(h, nodes_allowed, 0)) |
1da177e4 | 1444 | break; |
1da177e4 | 1445 | } |
a5516438 | 1446 | while (count < persistent_huge_pages(h)) { |
6ae11b27 | 1447 | if (!adjust_pool_surplus(h, nodes_allowed, 1)) |
7893d1d5 AL |
1448 | break; |
1449 | } | |
1450 | out: | |
a5516438 | 1451 | ret = persistent_huge_pages(h); |
1da177e4 | 1452 | spin_unlock(&hugetlb_lock); |
7893d1d5 | 1453 | return ret; |
1da177e4 LT |
1454 | } |
1455 | ||
a3437870 NA |
1456 | #define HSTATE_ATTR_RO(_name) \ |
1457 | static struct kobj_attribute _name##_attr = __ATTR_RO(_name) | |
1458 | ||
1459 | #define HSTATE_ATTR(_name) \ | |
1460 | static struct kobj_attribute _name##_attr = \ | |
1461 | __ATTR(_name, 0644, _name##_show, _name##_store) | |
1462 | ||
1463 | static struct kobject *hugepages_kobj; | |
1464 | static struct kobject *hstate_kobjs[HUGE_MAX_HSTATE]; | |
1465 | ||
9a305230 LS |
1466 | static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp); |
1467 | ||
1468 | static struct hstate *kobj_to_hstate(struct kobject *kobj, int *nidp) | |
a3437870 NA |
1469 | { |
1470 | int i; | |
9a305230 | 1471 | |
a3437870 | 1472 | for (i = 0; i < HUGE_MAX_HSTATE; i++) |
9a305230 LS |
1473 | if (hstate_kobjs[i] == kobj) { |
1474 | if (nidp) | |
1475 | *nidp = NUMA_NO_NODE; | |
a3437870 | 1476 | return &hstates[i]; |
9a305230 LS |
1477 | } |
1478 | ||
1479 | return kobj_to_node_hstate(kobj, nidp); | |
a3437870 NA |
1480 | } |
1481 | ||
06808b08 | 1482 | static ssize_t nr_hugepages_show_common(struct kobject *kobj, |
a3437870 NA |
1483 | struct kobj_attribute *attr, char *buf) |
1484 | { | |
9a305230 LS |
1485 | struct hstate *h; |
1486 | unsigned long nr_huge_pages; | |
1487 | int nid; | |
1488 | ||
1489 | h = kobj_to_hstate(kobj, &nid); | |
1490 | if (nid == NUMA_NO_NODE) | |
1491 | nr_huge_pages = h->nr_huge_pages; | |
1492 | else | |
1493 | nr_huge_pages = h->nr_huge_pages_node[nid]; | |
1494 | ||
1495 | return sprintf(buf, "%lu\n", nr_huge_pages); | |
a3437870 | 1496 | } |
adbe8726 | 1497 | |
06808b08 LS |
1498 | static ssize_t nr_hugepages_store_common(bool obey_mempolicy, |
1499 | struct kobject *kobj, struct kobj_attribute *attr, | |
1500 | const char *buf, size_t len) | |
a3437870 NA |
1501 | { |
1502 | int err; | |
9a305230 | 1503 | int nid; |
06808b08 | 1504 | unsigned long count; |
9a305230 | 1505 | struct hstate *h; |
bad44b5b | 1506 | NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | __GFP_NORETRY); |
a3437870 | 1507 | |
06808b08 | 1508 | err = strict_strtoul(buf, 10, &count); |
73ae31e5 | 1509 | if (err) |
adbe8726 | 1510 | goto out; |
a3437870 | 1511 | |
9a305230 | 1512 | h = kobj_to_hstate(kobj, &nid); |
adbe8726 EM |
1513 | if (h->order >= MAX_ORDER) { |
1514 | err = -EINVAL; | |
1515 | goto out; | |
1516 | } | |
1517 | ||
9a305230 LS |
1518 | if (nid == NUMA_NO_NODE) { |
1519 | /* | |
1520 | * global hstate attribute | |
1521 | */ | |
1522 | if (!(obey_mempolicy && | |
1523 | init_nodemask_of_mempolicy(nodes_allowed))) { | |
1524 | NODEMASK_FREE(nodes_allowed); | |
1525 | nodes_allowed = &node_states[N_HIGH_MEMORY]; | |
1526 | } | |
1527 | } else if (nodes_allowed) { | |
1528 | /* | |
1529 | * per node hstate attribute: adjust count to global, | |
1530 | * but restrict alloc/free to the specified node. | |
1531 | */ | |
1532 | count += h->nr_huge_pages - h->nr_huge_pages_node[nid]; | |
1533 | init_nodemask_of_node(nodes_allowed, nid); | |
1534 | } else | |
1535 | nodes_allowed = &node_states[N_HIGH_MEMORY]; | |
1536 | ||
06808b08 | 1537 | h->max_huge_pages = set_max_huge_pages(h, count, nodes_allowed); |
a3437870 | 1538 | |
9b5e5d0f | 1539 | if (nodes_allowed != &node_states[N_HIGH_MEMORY]) |
06808b08 LS |
1540 | NODEMASK_FREE(nodes_allowed); |
1541 | ||
1542 | return len; | |
adbe8726 EM |
1543 | out: |
1544 | NODEMASK_FREE(nodes_allowed); | |
1545 | return err; | |
06808b08 LS |
1546 | } |
1547 | ||
1548 | static ssize_t nr_hugepages_show(struct kobject *kobj, | |
1549 | struct kobj_attribute *attr, char *buf) | |
1550 | { | |
1551 | return nr_hugepages_show_common(kobj, attr, buf); | |
1552 | } | |
1553 | ||
1554 | static ssize_t nr_hugepages_store(struct kobject *kobj, | |
1555 | struct kobj_attribute *attr, const char *buf, size_t len) | |
1556 | { | |
1557 | return nr_hugepages_store_common(false, kobj, attr, buf, len); | |
a3437870 NA |
1558 | } |
1559 | HSTATE_ATTR(nr_hugepages); | |
1560 | ||
06808b08 LS |
1561 | #ifdef CONFIG_NUMA |
1562 | ||
1563 | /* | |
1564 | * hstate attribute for optionally mempolicy-based constraint on persistent | |
1565 | * huge page alloc/free. | |
1566 | */ | |
1567 | static ssize_t nr_hugepages_mempolicy_show(struct kobject *kobj, | |
1568 | struct kobj_attribute *attr, char *buf) | |
1569 | { | |
1570 | return nr_hugepages_show_common(kobj, attr, buf); | |
1571 | } | |
1572 | ||
1573 | static ssize_t nr_hugepages_mempolicy_store(struct kobject *kobj, | |
1574 | struct kobj_attribute *attr, const char *buf, size_t len) | |
1575 | { | |
1576 | return nr_hugepages_store_common(true, kobj, attr, buf, len); | |
1577 | } | |
1578 | HSTATE_ATTR(nr_hugepages_mempolicy); | |
1579 | #endif | |
1580 | ||
1581 | ||
a3437870 NA |
1582 | static ssize_t nr_overcommit_hugepages_show(struct kobject *kobj, |
1583 | struct kobj_attribute *attr, char *buf) | |
1584 | { | |
9a305230 | 1585 | struct hstate *h = kobj_to_hstate(kobj, NULL); |
a3437870 NA |
1586 | return sprintf(buf, "%lu\n", h->nr_overcommit_huge_pages); |
1587 | } | |
adbe8726 | 1588 | |
a3437870 NA |
1589 | static ssize_t nr_overcommit_hugepages_store(struct kobject *kobj, |
1590 | struct kobj_attribute *attr, const char *buf, size_t count) | |
1591 | { | |
1592 | int err; | |
1593 | unsigned long input; | |
9a305230 | 1594 | struct hstate *h = kobj_to_hstate(kobj, NULL); |
a3437870 | 1595 | |
adbe8726 EM |
1596 | if (h->order >= MAX_ORDER) |
1597 | return -EINVAL; | |
1598 | ||
a3437870 NA |
1599 | err = strict_strtoul(buf, 10, &input); |
1600 | if (err) | |
73ae31e5 | 1601 | return err; |
a3437870 NA |
1602 | |
1603 | spin_lock(&hugetlb_lock); | |
1604 | h->nr_overcommit_huge_pages = input; | |
1605 | spin_unlock(&hugetlb_lock); | |
1606 | ||
1607 | return count; | |
1608 | } | |
1609 | HSTATE_ATTR(nr_overcommit_hugepages); | |
1610 | ||
1611 | static ssize_t free_hugepages_show(struct kobject *kobj, | |
1612 | struct kobj_attribute *attr, char *buf) | |
1613 | { | |
9a305230 LS |
1614 | struct hstate *h; |
1615 | unsigned long free_huge_pages; | |
1616 | int nid; | |
1617 | ||
1618 | h = kobj_to_hstate(kobj, &nid); | |
1619 | if (nid == NUMA_NO_NODE) | |
1620 | free_huge_pages = h->free_huge_pages; | |
1621 | else | |
1622 | free_huge_pages = h->free_huge_pages_node[nid]; | |
1623 | ||
1624 | return sprintf(buf, "%lu\n", free_huge_pages); | |
a3437870 NA |
1625 | } |
1626 | HSTATE_ATTR_RO(free_hugepages); | |
1627 | ||
1628 | static ssize_t resv_hugepages_show(struct kobject *kobj, | |
1629 | struct kobj_attribute *attr, char *buf) | |
1630 | { | |
9a305230 | 1631 | struct hstate *h = kobj_to_hstate(kobj, NULL); |
a3437870 NA |
1632 | return sprintf(buf, "%lu\n", h->resv_huge_pages); |
1633 | } | |
1634 | HSTATE_ATTR_RO(resv_hugepages); | |
1635 | ||
1636 | static ssize_t surplus_hugepages_show(struct kobject *kobj, | |
1637 | struct kobj_attribute *attr, char *buf) | |
1638 | { | |
9a305230 LS |
1639 | struct hstate *h; |
1640 | unsigned long surplus_huge_pages; | |
1641 | int nid; | |
1642 | ||
1643 | h = kobj_to_hstate(kobj, &nid); | |
1644 | if (nid == NUMA_NO_NODE) | |
1645 | surplus_huge_pages = h->surplus_huge_pages; | |
1646 | else | |
1647 | surplus_huge_pages = h->surplus_huge_pages_node[nid]; | |
1648 | ||
1649 | return sprintf(buf, "%lu\n", surplus_huge_pages); | |
a3437870 NA |
1650 | } |
1651 | HSTATE_ATTR_RO(surplus_hugepages); | |
1652 | ||
1653 | static struct attribute *hstate_attrs[] = { | |
1654 | &nr_hugepages_attr.attr, | |
1655 | &nr_overcommit_hugepages_attr.attr, | |
1656 | &free_hugepages_attr.attr, | |
1657 | &resv_hugepages_attr.attr, | |
1658 | &surplus_hugepages_attr.attr, | |
06808b08 LS |
1659 | #ifdef CONFIG_NUMA |
1660 | &nr_hugepages_mempolicy_attr.attr, | |
1661 | #endif | |
a3437870 NA |
1662 | NULL, |
1663 | }; | |
1664 | ||
1665 | static struct attribute_group hstate_attr_group = { | |
1666 | .attrs = hstate_attrs, | |
1667 | }; | |
1668 | ||
094e9539 JM |
1669 | static int hugetlb_sysfs_add_hstate(struct hstate *h, struct kobject *parent, |
1670 | struct kobject **hstate_kobjs, | |
1671 | struct attribute_group *hstate_attr_group) | |
a3437870 NA |
1672 | { |
1673 | int retval; | |
972dc4de | 1674 | int hi = hstate_index(h); |
a3437870 | 1675 | |
9a305230 LS |
1676 | hstate_kobjs[hi] = kobject_create_and_add(h->name, parent); |
1677 | if (!hstate_kobjs[hi]) | |
a3437870 NA |
1678 | return -ENOMEM; |
1679 | ||
9a305230 | 1680 | retval = sysfs_create_group(hstate_kobjs[hi], hstate_attr_group); |
a3437870 | 1681 | if (retval) |
9a305230 | 1682 | kobject_put(hstate_kobjs[hi]); |
a3437870 NA |
1683 | |
1684 | return retval; | |
1685 | } | |
1686 | ||
1687 | static void __init hugetlb_sysfs_init(void) | |
1688 | { | |
1689 | struct hstate *h; | |
1690 | int err; | |
1691 | ||
1692 | hugepages_kobj = kobject_create_and_add("hugepages", mm_kobj); | |
1693 | if (!hugepages_kobj) | |
1694 | return; | |
1695 | ||
1696 | for_each_hstate(h) { | |
9a305230 LS |
1697 | err = hugetlb_sysfs_add_hstate(h, hugepages_kobj, |
1698 | hstate_kobjs, &hstate_attr_group); | |
a3437870 NA |
1699 | if (err) |
1700 | printk(KERN_ERR "Hugetlb: Unable to add hstate %s", | |
1701 | h->name); | |
1702 | } | |
1703 | } | |
1704 | ||
9a305230 LS |
1705 | #ifdef CONFIG_NUMA |
1706 | ||
1707 | /* | |
1708 | * node_hstate/s - associate per node hstate attributes, via their kobjects, | |
10fbcf4c KS |
1709 | * with node devices in node_devices[] using a parallel array. The array |
1710 | * index of a node device or _hstate == node id. | |
1711 | * This is here to avoid any static dependency of the node device driver, in | |
9a305230 LS |
1712 | * the base kernel, on the hugetlb module. |
1713 | */ | |
1714 | struct node_hstate { | |
1715 | struct kobject *hugepages_kobj; | |
1716 | struct kobject *hstate_kobjs[HUGE_MAX_HSTATE]; | |
1717 | }; | |
1718 | struct node_hstate node_hstates[MAX_NUMNODES]; | |
1719 | ||
1720 | /* | |
10fbcf4c | 1721 | * A subset of global hstate attributes for node devices |
9a305230 LS |
1722 | */ |
1723 | static struct attribute *per_node_hstate_attrs[] = { | |
1724 | &nr_hugepages_attr.attr, | |
1725 | &free_hugepages_attr.attr, | |
1726 | &surplus_hugepages_attr.attr, | |
1727 | NULL, | |
1728 | }; | |
1729 | ||
1730 | static struct attribute_group per_node_hstate_attr_group = { | |
1731 | .attrs = per_node_hstate_attrs, | |
1732 | }; | |
1733 | ||
1734 | /* | |
10fbcf4c | 1735 | * kobj_to_node_hstate - lookup global hstate for node device hstate attr kobj. |
9a305230 LS |
1736 | * Returns node id via non-NULL nidp. |
1737 | */ | |
1738 | static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) | |
1739 | { | |
1740 | int nid; | |
1741 | ||
1742 | for (nid = 0; nid < nr_node_ids; nid++) { | |
1743 | struct node_hstate *nhs = &node_hstates[nid]; | |
1744 | int i; | |
1745 | for (i = 0; i < HUGE_MAX_HSTATE; i++) | |
1746 | if (nhs->hstate_kobjs[i] == kobj) { | |
1747 | if (nidp) | |
1748 | *nidp = nid; | |
1749 | return &hstates[i]; | |
1750 | } | |
1751 | } | |
1752 | ||
1753 | BUG(); | |
1754 | return NULL; | |
1755 | } | |
1756 | ||
1757 | /* | |
10fbcf4c | 1758 | * Unregister hstate attributes from a single node device. |
9a305230 LS |
1759 | * No-op if no hstate attributes attached. |
1760 | */ | |
1761 | void hugetlb_unregister_node(struct node *node) | |
1762 | { | |
1763 | struct hstate *h; | |
10fbcf4c | 1764 | struct node_hstate *nhs = &node_hstates[node->dev.id]; |
9a305230 LS |
1765 | |
1766 | if (!nhs->hugepages_kobj) | |
9b5e5d0f | 1767 | return; /* no hstate attributes */ |
9a305230 | 1768 | |
972dc4de AK |
1769 | for_each_hstate(h) { |
1770 | int idx = hstate_index(h); | |
1771 | if (nhs->hstate_kobjs[idx]) { | |
1772 | kobject_put(nhs->hstate_kobjs[idx]); | |
1773 | nhs->hstate_kobjs[idx] = NULL; | |
9a305230 | 1774 | } |
972dc4de | 1775 | } |
9a305230 LS |
1776 | |
1777 | kobject_put(nhs->hugepages_kobj); | |
1778 | nhs->hugepages_kobj = NULL; | |
1779 | } | |
1780 | ||
1781 | /* | |
10fbcf4c | 1782 | * hugetlb module exit: unregister hstate attributes from node devices |
9a305230 LS |
1783 | * that have them. |
1784 | */ | |
1785 | static void hugetlb_unregister_all_nodes(void) | |
1786 | { | |
1787 | int nid; | |
1788 | ||
1789 | /* | |
10fbcf4c | 1790 | * disable node device registrations. |
9a305230 LS |
1791 | */ |
1792 | register_hugetlbfs_with_node(NULL, NULL); | |
1793 | ||
1794 | /* | |
1795 | * remove hstate attributes from any nodes that have them. | |
1796 | */ | |
1797 | for (nid = 0; nid < nr_node_ids; nid++) | |
1798 | hugetlb_unregister_node(&node_devices[nid]); | |
1799 | } | |
1800 | ||
1801 | /* | |
10fbcf4c | 1802 | * Register hstate attributes for a single node device. |
9a305230 LS |
1803 | * No-op if attributes already registered. |
1804 | */ | |
1805 | void hugetlb_register_node(struct node *node) | |
1806 | { | |
1807 | struct hstate *h; | |
10fbcf4c | 1808 | struct node_hstate *nhs = &node_hstates[node->dev.id]; |
9a305230 LS |
1809 | int err; |
1810 | ||
1811 | if (nhs->hugepages_kobj) | |
1812 | return; /* already allocated */ | |
1813 | ||
1814 | nhs->hugepages_kobj = kobject_create_and_add("hugepages", | |
10fbcf4c | 1815 | &node->dev.kobj); |
9a305230 LS |
1816 | if (!nhs->hugepages_kobj) |
1817 | return; | |
1818 | ||
1819 | for_each_hstate(h) { | |
1820 | err = hugetlb_sysfs_add_hstate(h, nhs->hugepages_kobj, | |
1821 | nhs->hstate_kobjs, | |
1822 | &per_node_hstate_attr_group); | |
1823 | if (err) { | |
1824 | printk(KERN_ERR "Hugetlb: Unable to add hstate %s" | |
1825 | " for node %d\n", | |
10fbcf4c | 1826 | h->name, node->dev.id); |
9a305230 LS |
1827 | hugetlb_unregister_node(node); |
1828 | break; | |
1829 | } | |
1830 | } | |
1831 | } | |
1832 | ||
1833 | /* | |
9b5e5d0f | 1834 | * hugetlb init time: register hstate attributes for all registered node |
10fbcf4c KS |
1835 | * devices of nodes that have memory. All on-line nodes should have |
1836 | * registered their associated device by this time. | |
9a305230 LS |
1837 | */ |
1838 | static void hugetlb_register_all_nodes(void) | |
1839 | { | |
1840 | int nid; | |
1841 | ||
9b5e5d0f | 1842 | for_each_node_state(nid, N_HIGH_MEMORY) { |
9a305230 | 1843 | struct node *node = &node_devices[nid]; |
10fbcf4c | 1844 | if (node->dev.id == nid) |
9a305230 LS |
1845 | hugetlb_register_node(node); |
1846 | } | |
1847 | ||
1848 | /* | |
10fbcf4c | 1849 | * Let the node device driver know we're here so it can |
9a305230 LS |
1850 | * [un]register hstate attributes on node hotplug. |
1851 | */ | |
1852 | register_hugetlbfs_with_node(hugetlb_register_node, | |
1853 | hugetlb_unregister_node); | |
1854 | } | |
1855 | #else /* !CONFIG_NUMA */ | |
1856 | ||
1857 | static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) | |
1858 | { | |
1859 | BUG(); | |
1860 | if (nidp) | |
1861 | *nidp = -1; | |
1862 | return NULL; | |
1863 | } | |
1864 | ||
1865 | static void hugetlb_unregister_all_nodes(void) { } | |
1866 | ||
1867 | static void hugetlb_register_all_nodes(void) { } | |
1868 | ||
1869 | #endif | |
1870 | ||
a3437870 NA |
1871 | static void __exit hugetlb_exit(void) |
1872 | { | |
1873 | struct hstate *h; | |
1874 | ||
9a305230 LS |
1875 | hugetlb_unregister_all_nodes(); |
1876 | ||
a3437870 | 1877 | for_each_hstate(h) { |
972dc4de | 1878 | kobject_put(hstate_kobjs[hstate_index(h)]); |
a3437870 NA |
1879 | } |
1880 | ||
1881 | kobject_put(hugepages_kobj); | |
1882 | } | |
1883 | module_exit(hugetlb_exit); | |
1884 | ||
1885 | static int __init hugetlb_init(void) | |
1886 | { | |
0ef89d25 BH |
1887 | /* Some platform decide whether they support huge pages at boot |
1888 | * time. On these, such as powerpc, HPAGE_SHIFT is set to 0 when | |
1889 | * there is no such support | |
1890 | */ | |
1891 | if (HPAGE_SHIFT == 0) | |
1892 | return 0; | |
a3437870 | 1893 | |
e11bfbfc NP |
1894 | if (!size_to_hstate(default_hstate_size)) { |
1895 | default_hstate_size = HPAGE_SIZE; | |
1896 | if (!size_to_hstate(default_hstate_size)) | |
1897 | hugetlb_add_hstate(HUGETLB_PAGE_ORDER); | |
a3437870 | 1898 | } |
972dc4de | 1899 | default_hstate_idx = hstate_index(size_to_hstate(default_hstate_size)); |
e11bfbfc NP |
1900 | if (default_hstate_max_huge_pages) |
1901 | default_hstate.max_huge_pages = default_hstate_max_huge_pages; | |
a3437870 NA |
1902 | |
1903 | hugetlb_init_hstates(); | |
1904 | ||
aa888a74 AK |
1905 | gather_bootmem_prealloc(); |
1906 | ||
a3437870 NA |
1907 | report_hugepages(); |
1908 | ||
1909 | hugetlb_sysfs_init(); | |
1910 | ||
9a305230 LS |
1911 | hugetlb_register_all_nodes(); |
1912 | ||
a3437870 NA |
1913 | return 0; |
1914 | } | |
1915 | module_init(hugetlb_init); | |
1916 | ||
1917 | /* Should be called on processing a hugepagesz=... option */ | |
1918 | void __init hugetlb_add_hstate(unsigned order) | |
1919 | { | |
1920 | struct hstate *h; | |
8faa8b07 AK |
1921 | unsigned long i; |
1922 | ||
a3437870 NA |
1923 | if (size_to_hstate(PAGE_SIZE << order)) { |
1924 | printk(KERN_WARNING "hugepagesz= specified twice, ignoring\n"); | |
1925 | return; | |
1926 | } | |
47d38344 | 1927 | BUG_ON(hugetlb_max_hstate >= HUGE_MAX_HSTATE); |
a3437870 | 1928 | BUG_ON(order == 0); |
47d38344 | 1929 | h = &hstates[hugetlb_max_hstate++]; |
a3437870 NA |
1930 | h->order = order; |
1931 | h->mask = ~((1ULL << (order + PAGE_SHIFT)) - 1); | |
8faa8b07 AK |
1932 | h->nr_huge_pages = 0; |
1933 | h->free_huge_pages = 0; | |
1934 | for (i = 0; i < MAX_NUMNODES; ++i) | |
1935 | INIT_LIST_HEAD(&h->hugepage_freelists[i]); | |
0edaecfa | 1936 | INIT_LIST_HEAD(&h->hugepage_activelist); |
9b5e5d0f LS |
1937 | h->next_nid_to_alloc = first_node(node_states[N_HIGH_MEMORY]); |
1938 | h->next_nid_to_free = first_node(node_states[N_HIGH_MEMORY]); | |
a3437870 NA |
1939 | snprintf(h->name, HSTATE_NAME_LEN, "hugepages-%lukB", |
1940 | huge_page_size(h)/1024); | |
abb8206c AK |
1941 | /* |
1942 | * Add cgroup control files only if the huge page consists | |
1943 | * of more than two normal pages. This is because we use | |
1944 | * page[2].lru.next for storing cgoup details. | |
1945 | */ | |
1946 | if (order >= HUGETLB_CGROUP_MIN_ORDER) | |
1947 | hugetlb_cgroup_file_init(hugetlb_max_hstate - 1); | |
8faa8b07 | 1948 | |
a3437870 NA |
1949 | parsed_hstate = h; |
1950 | } | |
1951 | ||
e11bfbfc | 1952 | static int __init hugetlb_nrpages_setup(char *s) |
a3437870 NA |
1953 | { |
1954 | unsigned long *mhp; | |
8faa8b07 | 1955 | static unsigned long *last_mhp; |
a3437870 NA |
1956 | |
1957 | /* | |
47d38344 | 1958 | * !hugetlb_max_hstate means we haven't parsed a hugepagesz= parameter yet, |
a3437870 NA |
1959 | * so this hugepages= parameter goes to the "default hstate". |
1960 | */ | |
47d38344 | 1961 | if (!hugetlb_max_hstate) |
a3437870 NA |
1962 | mhp = &default_hstate_max_huge_pages; |
1963 | else | |
1964 | mhp = &parsed_hstate->max_huge_pages; | |
1965 | ||
8faa8b07 AK |
1966 | if (mhp == last_mhp) { |
1967 | printk(KERN_WARNING "hugepages= specified twice without " | |
1968 | "interleaving hugepagesz=, ignoring\n"); | |
1969 | return 1; | |
1970 | } | |
1971 | ||
a3437870 NA |
1972 | if (sscanf(s, "%lu", mhp) <= 0) |
1973 | *mhp = 0; | |
1974 | ||
8faa8b07 AK |
1975 | /* |
1976 | * Global state is always initialized later in hugetlb_init. | |
1977 | * But we need to allocate >= MAX_ORDER hstates here early to still | |
1978 | * use the bootmem allocator. | |
1979 | */ | |
47d38344 | 1980 | if (hugetlb_max_hstate && parsed_hstate->order >= MAX_ORDER) |
8faa8b07 AK |
1981 | hugetlb_hstate_alloc_pages(parsed_hstate); |
1982 | ||
1983 | last_mhp = mhp; | |
1984 | ||
a3437870 NA |
1985 | return 1; |
1986 | } | |
e11bfbfc NP |
1987 | __setup("hugepages=", hugetlb_nrpages_setup); |
1988 | ||
1989 | static int __init hugetlb_default_setup(char *s) | |
1990 | { | |
1991 | default_hstate_size = memparse(s, &s); | |
1992 | return 1; | |
1993 | } | |
1994 | __setup("default_hugepagesz=", hugetlb_default_setup); | |
a3437870 | 1995 | |
8a213460 NA |
1996 | static unsigned int cpuset_mems_nr(unsigned int *array) |
1997 | { | |
1998 | int node; | |
1999 | unsigned int nr = 0; | |
2000 | ||
2001 | for_each_node_mask(node, cpuset_current_mems_allowed) | |
2002 | nr += array[node]; | |
2003 | ||
2004 | return nr; | |
2005 | } | |
2006 | ||
2007 | #ifdef CONFIG_SYSCTL | |
06808b08 LS |
2008 | static int hugetlb_sysctl_handler_common(bool obey_mempolicy, |
2009 | struct ctl_table *table, int write, | |
2010 | void __user *buffer, size_t *length, loff_t *ppos) | |
1da177e4 | 2011 | { |
e5ff2159 AK |
2012 | struct hstate *h = &default_hstate; |
2013 | unsigned long tmp; | |
08d4a246 | 2014 | int ret; |
e5ff2159 | 2015 | |
c033a93c | 2016 | tmp = h->max_huge_pages; |
e5ff2159 | 2017 | |
adbe8726 EM |
2018 | if (write && h->order >= MAX_ORDER) |
2019 | return -EINVAL; | |
2020 | ||
e5ff2159 AK |
2021 | table->data = &tmp; |
2022 | table->maxlen = sizeof(unsigned long); | |
08d4a246 MH |
2023 | ret = proc_doulongvec_minmax(table, write, buffer, length, ppos); |
2024 | if (ret) | |
2025 | goto out; | |
e5ff2159 | 2026 | |
06808b08 | 2027 | if (write) { |
bad44b5b DR |
2028 | NODEMASK_ALLOC(nodemask_t, nodes_allowed, |
2029 | GFP_KERNEL | __GFP_NORETRY); | |
06808b08 LS |
2030 | if (!(obey_mempolicy && |
2031 | init_nodemask_of_mempolicy(nodes_allowed))) { | |
2032 | NODEMASK_FREE(nodes_allowed); | |
2033 | nodes_allowed = &node_states[N_HIGH_MEMORY]; | |
2034 | } | |
2035 | h->max_huge_pages = set_max_huge_pages(h, tmp, nodes_allowed); | |
2036 | ||
2037 | if (nodes_allowed != &node_states[N_HIGH_MEMORY]) | |
2038 | NODEMASK_FREE(nodes_allowed); | |
2039 | } | |
08d4a246 MH |
2040 | out: |
2041 | return ret; | |
1da177e4 | 2042 | } |
396faf03 | 2043 | |
06808b08 LS |
2044 | int hugetlb_sysctl_handler(struct ctl_table *table, int write, |
2045 | void __user *buffer, size_t *length, loff_t *ppos) | |
2046 | { | |
2047 | ||
2048 | return hugetlb_sysctl_handler_common(false, table, write, | |
2049 | buffer, length, ppos); | |
2050 | } | |
2051 | ||
2052 | #ifdef CONFIG_NUMA | |
2053 | int hugetlb_mempolicy_sysctl_handler(struct ctl_table *table, int write, | |
2054 | void __user *buffer, size_t *length, loff_t *ppos) | |
2055 | { | |
2056 | return hugetlb_sysctl_handler_common(true, table, write, | |
2057 | buffer, length, ppos); | |
2058 | } | |
2059 | #endif /* CONFIG_NUMA */ | |
2060 | ||
396faf03 | 2061 | int hugetlb_treat_movable_handler(struct ctl_table *table, int write, |
8d65af78 | 2062 | void __user *buffer, |
396faf03 MG |
2063 | size_t *length, loff_t *ppos) |
2064 | { | |
8d65af78 | 2065 | proc_dointvec(table, write, buffer, length, ppos); |
396faf03 MG |
2066 | if (hugepages_treat_as_movable) |
2067 | htlb_alloc_mask = GFP_HIGHUSER_MOVABLE; | |
2068 | else | |
2069 | htlb_alloc_mask = GFP_HIGHUSER; | |
2070 | return 0; | |
2071 | } | |
2072 | ||
a3d0c6aa | 2073 | int hugetlb_overcommit_handler(struct ctl_table *table, int write, |
8d65af78 | 2074 | void __user *buffer, |
a3d0c6aa NA |
2075 | size_t *length, loff_t *ppos) |
2076 | { | |
a5516438 | 2077 | struct hstate *h = &default_hstate; |
e5ff2159 | 2078 | unsigned long tmp; |
08d4a246 | 2079 | int ret; |
e5ff2159 | 2080 | |
c033a93c | 2081 | tmp = h->nr_overcommit_huge_pages; |
e5ff2159 | 2082 | |
adbe8726 EM |
2083 | if (write && h->order >= MAX_ORDER) |
2084 | return -EINVAL; | |
2085 | ||
e5ff2159 AK |
2086 | table->data = &tmp; |
2087 | table->maxlen = sizeof(unsigned long); | |
08d4a246 MH |
2088 | ret = proc_doulongvec_minmax(table, write, buffer, length, ppos); |
2089 | if (ret) | |
2090 | goto out; | |
e5ff2159 AK |
2091 | |
2092 | if (write) { | |
2093 | spin_lock(&hugetlb_lock); | |
2094 | h->nr_overcommit_huge_pages = tmp; | |
2095 | spin_unlock(&hugetlb_lock); | |
2096 | } | |
08d4a246 MH |
2097 | out: |
2098 | return ret; | |
a3d0c6aa NA |
2099 | } |
2100 | ||
1da177e4 LT |
2101 | #endif /* CONFIG_SYSCTL */ |
2102 | ||
e1759c21 | 2103 | void hugetlb_report_meminfo(struct seq_file *m) |
1da177e4 | 2104 | { |
a5516438 | 2105 | struct hstate *h = &default_hstate; |
e1759c21 | 2106 | seq_printf(m, |
4f98a2fe RR |
2107 | "HugePages_Total: %5lu\n" |
2108 | "HugePages_Free: %5lu\n" | |
2109 | "HugePages_Rsvd: %5lu\n" | |
2110 | "HugePages_Surp: %5lu\n" | |
2111 | "Hugepagesize: %8lu kB\n", | |
a5516438 AK |
2112 | h->nr_huge_pages, |
2113 | h->free_huge_pages, | |
2114 | h->resv_huge_pages, | |
2115 | h->surplus_huge_pages, | |
2116 | 1UL << (huge_page_order(h) + PAGE_SHIFT - 10)); | |
1da177e4 LT |
2117 | } |
2118 | ||
2119 | int hugetlb_report_node_meminfo(int nid, char *buf) | |
2120 | { | |
a5516438 | 2121 | struct hstate *h = &default_hstate; |
1da177e4 LT |
2122 | return sprintf(buf, |
2123 | "Node %d HugePages_Total: %5u\n" | |
a1de0919 NA |
2124 | "Node %d HugePages_Free: %5u\n" |
2125 | "Node %d HugePages_Surp: %5u\n", | |
a5516438 AK |
2126 | nid, h->nr_huge_pages_node[nid], |
2127 | nid, h->free_huge_pages_node[nid], | |
2128 | nid, h->surplus_huge_pages_node[nid]); | |
1da177e4 LT |
2129 | } |
2130 | ||
1da177e4 LT |
2131 | /* Return the number pages of memory we physically have, in PAGE_SIZE units. */ |
2132 | unsigned long hugetlb_total_pages(void) | |
2133 | { | |
a5516438 AK |
2134 | struct hstate *h = &default_hstate; |
2135 | return h->nr_huge_pages * pages_per_huge_page(h); | |
1da177e4 | 2136 | } |
1da177e4 | 2137 | |
a5516438 | 2138 | static int hugetlb_acct_memory(struct hstate *h, long delta) |
fc1b8a73 MG |
2139 | { |
2140 | int ret = -ENOMEM; | |
2141 | ||
2142 | spin_lock(&hugetlb_lock); | |
2143 | /* | |
2144 | * When cpuset is configured, it breaks the strict hugetlb page | |
2145 | * reservation as the accounting is done on a global variable. Such | |
2146 | * reservation is completely rubbish in the presence of cpuset because | |
2147 | * the reservation is not checked against page availability for the | |
2148 | * current cpuset. Application can still potentially OOM'ed by kernel | |
2149 | * with lack of free htlb page in cpuset that the task is in. | |
2150 | * Attempt to enforce strict accounting with cpuset is almost | |
2151 | * impossible (or too ugly) because cpuset is too fluid that | |
2152 | * task or memory node can be dynamically moved between cpusets. | |
2153 | * | |
2154 | * The change of semantics for shared hugetlb mapping with cpuset is | |
2155 | * undesirable. However, in order to preserve some of the semantics, | |
2156 | * we fall back to check against current free page availability as | |
2157 | * a best attempt and hopefully to minimize the impact of changing | |
2158 | * semantics that cpuset has. | |
2159 | */ | |
2160 | if (delta > 0) { | |
a5516438 | 2161 | if (gather_surplus_pages(h, delta) < 0) |
fc1b8a73 MG |
2162 | goto out; |
2163 | ||
a5516438 AK |
2164 | if (delta > cpuset_mems_nr(h->free_huge_pages_node)) { |
2165 | return_unused_surplus_pages(h, delta); | |
fc1b8a73 MG |
2166 | goto out; |
2167 | } | |
2168 | } | |
2169 | ||
2170 | ret = 0; | |
2171 | if (delta < 0) | |
a5516438 | 2172 | return_unused_surplus_pages(h, (unsigned long) -delta); |
fc1b8a73 MG |
2173 | |
2174 | out: | |
2175 | spin_unlock(&hugetlb_lock); | |
2176 | return ret; | |
2177 | } | |
2178 | ||
84afd99b AW |
2179 | static void hugetlb_vm_op_open(struct vm_area_struct *vma) |
2180 | { | |
2181 | struct resv_map *reservations = vma_resv_map(vma); | |
2182 | ||
2183 | /* | |
2184 | * This new VMA should share its siblings reservation map if present. | |
2185 | * The VMA will only ever have a valid reservation map pointer where | |
2186 | * it is being copied for another still existing VMA. As that VMA | |
25985edc | 2187 | * has a reference to the reservation map it cannot disappear until |
84afd99b AW |
2188 | * after this open call completes. It is therefore safe to take a |
2189 | * new reference here without additional locking. | |
2190 | */ | |
2191 | if (reservations) | |
2192 | kref_get(&reservations->refs); | |
2193 | } | |
2194 | ||
c50ac050 DH |
2195 | static void resv_map_put(struct vm_area_struct *vma) |
2196 | { | |
2197 | struct resv_map *reservations = vma_resv_map(vma); | |
2198 | ||
2199 | if (!reservations) | |
2200 | return; | |
2201 | kref_put(&reservations->refs, resv_map_release); | |
2202 | } | |
2203 | ||
a1e78772 MG |
2204 | static void hugetlb_vm_op_close(struct vm_area_struct *vma) |
2205 | { | |
a5516438 | 2206 | struct hstate *h = hstate_vma(vma); |
84afd99b | 2207 | struct resv_map *reservations = vma_resv_map(vma); |
90481622 | 2208 | struct hugepage_subpool *spool = subpool_vma(vma); |
84afd99b AW |
2209 | unsigned long reserve; |
2210 | unsigned long start; | |
2211 | unsigned long end; | |
2212 | ||
2213 | if (reservations) { | |
a5516438 AK |
2214 | start = vma_hugecache_offset(h, vma, vma->vm_start); |
2215 | end = vma_hugecache_offset(h, vma, vma->vm_end); | |
84afd99b AW |
2216 | |
2217 | reserve = (end - start) - | |
2218 | region_count(&reservations->regions, start, end); | |
2219 | ||
c50ac050 | 2220 | resv_map_put(vma); |
84afd99b | 2221 | |
7251ff78 | 2222 | if (reserve) { |
a5516438 | 2223 | hugetlb_acct_memory(h, -reserve); |
90481622 | 2224 | hugepage_subpool_put_pages(spool, reserve); |
7251ff78 | 2225 | } |
84afd99b | 2226 | } |
a1e78772 MG |
2227 | } |
2228 | ||
1da177e4 LT |
2229 | /* |
2230 | * We cannot handle pagefaults against hugetlb pages at all. They cause | |
2231 | * handle_mm_fault() to try to instantiate regular-sized pages in the | |
2232 | * hugegpage VMA. do_page_fault() is supposed to trap this, so BUG is we get | |
2233 | * this far. | |
2234 | */ | |
d0217ac0 | 2235 | static int hugetlb_vm_op_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
1da177e4 LT |
2236 | { |
2237 | BUG(); | |
d0217ac0 | 2238 | return 0; |
1da177e4 LT |
2239 | } |
2240 | ||
f0f37e2f | 2241 | const struct vm_operations_struct hugetlb_vm_ops = { |
d0217ac0 | 2242 | .fault = hugetlb_vm_op_fault, |
84afd99b | 2243 | .open = hugetlb_vm_op_open, |
a1e78772 | 2244 | .close = hugetlb_vm_op_close, |
1da177e4 LT |
2245 | }; |
2246 | ||
1e8f889b DG |
2247 | static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page, |
2248 | int writable) | |
63551ae0 DG |
2249 | { |
2250 | pte_t entry; | |
2251 | ||
1e8f889b | 2252 | if (writable) { |
63551ae0 DG |
2253 | entry = |
2254 | pte_mkwrite(pte_mkdirty(mk_pte(page, vma->vm_page_prot))); | |
2255 | } else { | |
7f2e9525 | 2256 | entry = huge_pte_wrprotect(mk_pte(page, vma->vm_page_prot)); |
63551ae0 DG |
2257 | } |
2258 | entry = pte_mkyoung(entry); | |
2259 | entry = pte_mkhuge(entry); | |
d9ed9faa | 2260 | entry = arch_make_huge_pte(entry, vma, page, writable); |
63551ae0 DG |
2261 | |
2262 | return entry; | |
2263 | } | |
2264 | ||
1e8f889b DG |
2265 | static void set_huge_ptep_writable(struct vm_area_struct *vma, |
2266 | unsigned long address, pte_t *ptep) | |
2267 | { | |
2268 | pte_t entry; | |
2269 | ||
7f2e9525 | 2270 | entry = pte_mkwrite(pte_mkdirty(huge_ptep_get(ptep))); |
32f84528 | 2271 | if (huge_ptep_set_access_flags(vma, address, ptep, entry, 1)) |
4b3073e1 | 2272 | update_mmu_cache(vma, address, ptep); |
1e8f889b DG |
2273 | } |
2274 | ||
2275 | ||
63551ae0 DG |
2276 | int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, |
2277 | struct vm_area_struct *vma) | |
2278 | { | |
2279 | pte_t *src_pte, *dst_pte, entry; | |
2280 | struct page *ptepage; | |
1c59827d | 2281 | unsigned long addr; |
1e8f889b | 2282 | int cow; |
a5516438 AK |
2283 | struct hstate *h = hstate_vma(vma); |
2284 | unsigned long sz = huge_page_size(h); | |
1e8f889b DG |
2285 | |
2286 | cow = (vma->vm_flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE; | |
63551ae0 | 2287 | |
a5516438 | 2288 | for (addr = vma->vm_start; addr < vma->vm_end; addr += sz) { |
c74df32c HD |
2289 | src_pte = huge_pte_offset(src, addr); |
2290 | if (!src_pte) | |
2291 | continue; | |
a5516438 | 2292 | dst_pte = huge_pte_alloc(dst, addr, sz); |
63551ae0 DG |
2293 | if (!dst_pte) |
2294 | goto nomem; | |
c5c99429 LW |
2295 | |
2296 | /* If the pagetables are shared don't copy or take references */ | |
2297 | if (dst_pte == src_pte) | |
2298 | continue; | |
2299 | ||
c74df32c | 2300 | spin_lock(&dst->page_table_lock); |
46478758 | 2301 | spin_lock_nested(&src->page_table_lock, SINGLE_DEPTH_NESTING); |
7f2e9525 | 2302 | if (!huge_pte_none(huge_ptep_get(src_pte))) { |
1e8f889b | 2303 | if (cow) |
7f2e9525 GS |
2304 | huge_ptep_set_wrprotect(src, addr, src_pte); |
2305 | entry = huge_ptep_get(src_pte); | |
1c59827d HD |
2306 | ptepage = pte_page(entry); |
2307 | get_page(ptepage); | |
0fe6e20b | 2308 | page_dup_rmap(ptepage); |
1c59827d HD |
2309 | set_huge_pte_at(dst, addr, dst_pte, entry); |
2310 | } | |
2311 | spin_unlock(&src->page_table_lock); | |
c74df32c | 2312 | spin_unlock(&dst->page_table_lock); |
63551ae0 DG |
2313 | } |
2314 | return 0; | |
2315 | ||
2316 | nomem: | |
2317 | return -ENOMEM; | |
2318 | } | |
2319 | ||
290408d4 NH |
2320 | static int is_hugetlb_entry_migration(pte_t pte) |
2321 | { | |
2322 | swp_entry_t swp; | |
2323 | ||
2324 | if (huge_pte_none(pte) || pte_present(pte)) | |
2325 | return 0; | |
2326 | swp = pte_to_swp_entry(pte); | |
32f84528 | 2327 | if (non_swap_entry(swp) && is_migration_entry(swp)) |
290408d4 | 2328 | return 1; |
32f84528 | 2329 | else |
290408d4 NH |
2330 | return 0; |
2331 | } | |
2332 | ||
fd6a03ed NH |
2333 | static int is_hugetlb_entry_hwpoisoned(pte_t pte) |
2334 | { | |
2335 | swp_entry_t swp; | |
2336 | ||
2337 | if (huge_pte_none(pte) || pte_present(pte)) | |
2338 | return 0; | |
2339 | swp = pte_to_swp_entry(pte); | |
32f84528 | 2340 | if (non_swap_entry(swp) && is_hwpoison_entry(swp)) |
fd6a03ed | 2341 | return 1; |
32f84528 | 2342 | else |
fd6a03ed NH |
2343 | return 0; |
2344 | } | |
2345 | ||
24669e58 AK |
2346 | void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, |
2347 | unsigned long start, unsigned long end, | |
2348 | struct page *ref_page) | |
63551ae0 | 2349 | { |
24669e58 | 2350 | int force_flush = 0; |
63551ae0 DG |
2351 | struct mm_struct *mm = vma->vm_mm; |
2352 | unsigned long address; | |
c7546f8f | 2353 | pte_t *ptep; |
63551ae0 DG |
2354 | pte_t pte; |
2355 | struct page *page; | |
a5516438 AK |
2356 | struct hstate *h = hstate_vma(vma); |
2357 | unsigned long sz = huge_page_size(h); | |
2358 | ||
63551ae0 | 2359 | WARN_ON(!is_vm_hugetlb_page(vma)); |
a5516438 AK |
2360 | BUG_ON(start & ~huge_page_mask(h)); |
2361 | BUG_ON(end & ~huge_page_mask(h)); | |
63551ae0 | 2362 | |
24669e58 | 2363 | tlb_start_vma(tlb, vma); |
cddb8a5c | 2364 | mmu_notifier_invalidate_range_start(mm, start, end); |
24669e58 | 2365 | again: |
508034a3 | 2366 | spin_lock(&mm->page_table_lock); |
a5516438 | 2367 | for (address = start; address < end; address += sz) { |
c7546f8f | 2368 | ptep = huge_pte_offset(mm, address); |
4c887265 | 2369 | if (!ptep) |
c7546f8f DG |
2370 | continue; |
2371 | ||
39dde65c CK |
2372 | if (huge_pmd_unshare(mm, &address, ptep)) |
2373 | continue; | |
2374 | ||
6629326b HD |
2375 | pte = huge_ptep_get(ptep); |
2376 | if (huge_pte_none(pte)) | |
2377 | continue; | |
2378 | ||
2379 | /* | |
2380 | * HWPoisoned hugepage is already unmapped and dropped reference | |
2381 | */ | |
2382 | if (unlikely(is_hugetlb_entry_hwpoisoned(pte))) | |
2383 | continue; | |
2384 | ||
2385 | page = pte_page(pte); | |
04f2cbe3 MG |
2386 | /* |
2387 | * If a reference page is supplied, it is because a specific | |
2388 | * page is being unmapped, not a range. Ensure the page we | |
2389 | * are about to unmap is the actual page of interest. | |
2390 | */ | |
2391 | if (ref_page) { | |
04f2cbe3 MG |
2392 | if (page != ref_page) |
2393 | continue; | |
2394 | ||
2395 | /* | |
2396 | * Mark the VMA as having unmapped its page so that | |
2397 | * future faults in this VMA will fail rather than | |
2398 | * looking like data was lost | |
2399 | */ | |
2400 | set_vma_resv_flags(vma, HPAGE_RESV_UNMAPPED); | |
2401 | } | |
2402 | ||
c7546f8f | 2403 | pte = huge_ptep_get_and_clear(mm, address, ptep); |
24669e58 | 2404 | tlb_remove_tlb_entry(tlb, ptep, address); |
6649a386 KC |
2405 | if (pte_dirty(pte)) |
2406 | set_page_dirty(page); | |
9e81130b | 2407 | |
24669e58 AK |
2408 | page_remove_rmap(page); |
2409 | force_flush = !__tlb_remove_page(tlb, page); | |
2410 | if (force_flush) | |
2411 | break; | |
9e81130b HD |
2412 | /* Bail out after unmapping reference page if supplied */ |
2413 | if (ref_page) | |
2414 | break; | |
63551ae0 | 2415 | } |
cd2934a3 | 2416 | spin_unlock(&mm->page_table_lock); |
24669e58 AK |
2417 | /* |
2418 | * mmu_gather ran out of room to batch pages, we break out of | |
2419 | * the PTE lock to avoid doing the potential expensive TLB invalidate | |
2420 | * and page-free while holding it. | |
2421 | */ | |
2422 | if (force_flush) { | |
2423 | force_flush = 0; | |
2424 | tlb_flush_mmu(tlb); | |
2425 | if (address < end && !ref_page) | |
2426 | goto again; | |
fe1668ae | 2427 | } |
24669e58 AK |
2428 | mmu_notifier_invalidate_range_end(mm, start, end); |
2429 | tlb_end_vma(tlb, vma); | |
1da177e4 | 2430 | } |
63551ae0 | 2431 | |
d833352a MG |
2432 | void __unmap_hugepage_range_final(struct mmu_gather *tlb, |
2433 | struct vm_area_struct *vma, unsigned long start, | |
2434 | unsigned long end, struct page *ref_page) | |
2435 | { | |
2436 | __unmap_hugepage_range(tlb, vma, start, end, ref_page); | |
2437 | ||
2438 | /* | |
2439 | * Clear this flag so that x86's huge_pmd_share page_table_shareable | |
2440 | * test will fail on a vma being torn down, and not grab a page table | |
2441 | * on its way out. We're lucky that the flag has such an appropriate | |
2442 | * name, and can in fact be safely cleared here. We could clear it | |
2443 | * before the __unmap_hugepage_range above, but all that's necessary | |
2444 | * is to clear it before releasing the i_mmap_mutex. This works | |
2445 | * because in the context this is called, the VMA is about to be | |
2446 | * destroyed and the i_mmap_mutex is held. | |
2447 | */ | |
2448 | vma->vm_flags &= ~VM_MAYSHARE; | |
2449 | } | |
2450 | ||
502717f4 | 2451 | void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, |
04f2cbe3 | 2452 | unsigned long end, struct page *ref_page) |
502717f4 | 2453 | { |
24669e58 AK |
2454 | struct mm_struct *mm; |
2455 | struct mmu_gather tlb; | |
2456 | ||
2457 | mm = vma->vm_mm; | |
2458 | ||
2459 | tlb_gather_mmu(&tlb, mm, 0); | |
2460 | __unmap_hugepage_range(&tlb, vma, start, end, ref_page); | |
2461 | tlb_finish_mmu(&tlb, start, end); | |
502717f4 CK |
2462 | } |
2463 | ||
04f2cbe3 MG |
2464 | /* |
2465 | * This is called when the original mapper is failing to COW a MAP_PRIVATE | |
2466 | * mappping it owns the reserve page for. The intention is to unmap the page | |
2467 | * from other VMAs and let the children be SIGKILLed if they are faulting the | |
2468 | * same region. | |
2469 | */ | |
2a4b3ded HH |
2470 | static int unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma, |
2471 | struct page *page, unsigned long address) | |
04f2cbe3 | 2472 | { |
7526674d | 2473 | struct hstate *h = hstate_vma(vma); |
04f2cbe3 MG |
2474 | struct vm_area_struct *iter_vma; |
2475 | struct address_space *mapping; | |
2476 | struct prio_tree_iter iter; | |
2477 | pgoff_t pgoff; | |
2478 | ||
2479 | /* | |
2480 | * vm_pgoff is in PAGE_SIZE units, hence the different calculation | |
2481 | * from page cache lookup which is in HPAGE_SIZE units. | |
2482 | */ | |
7526674d | 2483 | address = address & huge_page_mask(h); |
0c176d52 | 2484 | pgoff = vma_hugecache_offset(h, vma, address); |
90481622 | 2485 | mapping = vma->vm_file->f_dentry->d_inode->i_mapping; |
04f2cbe3 | 2486 | |
4eb2b1dc MG |
2487 | /* |
2488 | * Take the mapping lock for the duration of the table walk. As | |
2489 | * this mapping should be shared between all the VMAs, | |
2490 | * __unmap_hugepage_range() is called as the lock is already held | |
2491 | */ | |
3d48ae45 | 2492 | mutex_lock(&mapping->i_mmap_mutex); |
04f2cbe3 MG |
2493 | vma_prio_tree_foreach(iter_vma, &iter, &mapping->i_mmap, pgoff, pgoff) { |
2494 | /* Do not unmap the current VMA */ | |
2495 | if (iter_vma == vma) | |
2496 | continue; | |
2497 | ||
2498 | /* | |
2499 | * Unmap the page from other VMAs without their own reserves. | |
2500 | * They get marked to be SIGKILLed if they fault in these | |
2501 | * areas. This is because a future no-page fault on this VMA | |
2502 | * could insert a zeroed page instead of the data existing | |
2503 | * from the time of fork. This would look like data corruption | |
2504 | */ | |
2505 | if (!is_vma_resv_set(iter_vma, HPAGE_RESV_OWNER)) | |
24669e58 AK |
2506 | unmap_hugepage_range(iter_vma, address, |
2507 | address + huge_page_size(h), page); | |
04f2cbe3 | 2508 | } |
3d48ae45 | 2509 | mutex_unlock(&mapping->i_mmap_mutex); |
04f2cbe3 MG |
2510 | |
2511 | return 1; | |
2512 | } | |
2513 | ||
0fe6e20b NH |
2514 | /* |
2515 | * Hugetlb_cow() should be called with page lock of the original hugepage held. | |
ef009b25 MH |
2516 | * Called with hugetlb_instantiation_mutex held and pte_page locked so we |
2517 | * cannot race with other handlers or page migration. | |
2518 | * Keep the pte_same checks anyway to make transition from the mutex easier. | |
0fe6e20b | 2519 | */ |
1e8f889b | 2520 | static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma, |
04f2cbe3 MG |
2521 | unsigned long address, pte_t *ptep, pte_t pte, |
2522 | struct page *pagecache_page) | |
1e8f889b | 2523 | { |
a5516438 | 2524 | struct hstate *h = hstate_vma(vma); |
1e8f889b | 2525 | struct page *old_page, *new_page; |
79ac6ba4 | 2526 | int avoidcopy; |
04f2cbe3 | 2527 | int outside_reserve = 0; |
1e8f889b DG |
2528 | |
2529 | old_page = pte_page(pte); | |
2530 | ||
04f2cbe3 | 2531 | retry_avoidcopy: |
1e8f889b DG |
2532 | /* If no-one else is actually using this page, avoid the copy |
2533 | * and just make the page writable */ | |
0fe6e20b | 2534 | avoidcopy = (page_mapcount(old_page) == 1); |
1e8f889b | 2535 | if (avoidcopy) { |
56c9cfb1 NH |
2536 | if (PageAnon(old_page)) |
2537 | page_move_anon_rmap(old_page, vma, address); | |
1e8f889b | 2538 | set_huge_ptep_writable(vma, address, ptep); |
83c54070 | 2539 | return 0; |
1e8f889b DG |
2540 | } |
2541 | ||
04f2cbe3 MG |
2542 | /* |
2543 | * If the process that created a MAP_PRIVATE mapping is about to | |
2544 | * perform a COW due to a shared page count, attempt to satisfy | |
2545 | * the allocation without using the existing reserves. The pagecache | |
2546 | * page is used to determine if the reserve at this address was | |
2547 | * consumed or not. If reserves were used, a partial faulted mapping | |
2548 | * at the time of fork() could consume its reserves on COW instead | |
2549 | * of the full address range. | |
2550 | */ | |
f83a275d | 2551 | if (!(vma->vm_flags & VM_MAYSHARE) && |
04f2cbe3 MG |
2552 | is_vma_resv_set(vma, HPAGE_RESV_OWNER) && |
2553 | old_page != pagecache_page) | |
2554 | outside_reserve = 1; | |
2555 | ||
1e8f889b | 2556 | page_cache_get(old_page); |
b76c8cfb LW |
2557 | |
2558 | /* Drop page_table_lock as buddy allocator may be called */ | |
2559 | spin_unlock(&mm->page_table_lock); | |
04f2cbe3 | 2560 | new_page = alloc_huge_page(vma, address, outside_reserve); |
1e8f889b | 2561 | |
2fc39cec | 2562 | if (IS_ERR(new_page)) { |
76dcee75 | 2563 | long err = PTR_ERR(new_page); |
1e8f889b | 2564 | page_cache_release(old_page); |
04f2cbe3 MG |
2565 | |
2566 | /* | |
2567 | * If a process owning a MAP_PRIVATE mapping fails to COW, | |
2568 | * it is due to references held by a child and an insufficient | |
2569 | * huge page pool. To guarantee the original mappers | |
2570 | * reliability, unmap the page from child processes. The child | |
2571 | * may get SIGKILLed if it later faults. | |
2572 | */ | |
2573 | if (outside_reserve) { | |
2574 | BUG_ON(huge_pte_none(pte)); | |
2575 | if (unmap_ref_private(mm, vma, old_page, address)) { | |
04f2cbe3 | 2576 | BUG_ON(huge_pte_none(pte)); |
b76c8cfb | 2577 | spin_lock(&mm->page_table_lock); |
a734bcc8 HD |
2578 | ptep = huge_pte_offset(mm, address & huge_page_mask(h)); |
2579 | if (likely(pte_same(huge_ptep_get(ptep), pte))) | |
2580 | goto retry_avoidcopy; | |
2581 | /* | |
2582 | * race occurs while re-acquiring page_table_lock, and | |
2583 | * our job is done. | |
2584 | */ | |
2585 | return 0; | |
04f2cbe3 MG |
2586 | } |
2587 | WARN_ON_ONCE(1); | |
2588 | } | |
2589 | ||
b76c8cfb LW |
2590 | /* Caller expects lock to be held */ |
2591 | spin_lock(&mm->page_table_lock); | |
76dcee75 AK |
2592 | if (err == -ENOMEM) |
2593 | return VM_FAULT_OOM; | |
2594 | else | |
2595 | return VM_FAULT_SIGBUS; | |
1e8f889b DG |
2596 | } |
2597 | ||
0fe6e20b NH |
2598 | /* |
2599 | * When the original hugepage is shared one, it does not have | |
2600 | * anon_vma prepared. | |
2601 | */ | |
44e2aa93 | 2602 | if (unlikely(anon_vma_prepare(vma))) { |
ea4039a3 HD |
2603 | page_cache_release(new_page); |
2604 | page_cache_release(old_page); | |
44e2aa93 DN |
2605 | /* Caller expects lock to be held */ |
2606 | spin_lock(&mm->page_table_lock); | |
0fe6e20b | 2607 | return VM_FAULT_OOM; |
44e2aa93 | 2608 | } |
0fe6e20b | 2609 | |
47ad8475 AA |
2610 | copy_user_huge_page(new_page, old_page, address, vma, |
2611 | pages_per_huge_page(h)); | |
0ed361de | 2612 | __SetPageUptodate(new_page); |
1e8f889b | 2613 | |
b76c8cfb LW |
2614 | /* |
2615 | * Retake the page_table_lock to check for racing updates | |
2616 | * before the page tables are altered | |
2617 | */ | |
2618 | spin_lock(&mm->page_table_lock); | |
a5516438 | 2619 | ptep = huge_pte_offset(mm, address & huge_page_mask(h)); |
7f2e9525 | 2620 | if (likely(pte_same(huge_ptep_get(ptep), pte))) { |
1e8f889b | 2621 | /* Break COW */ |
3edd4fc9 DD |
2622 | mmu_notifier_invalidate_range_start(mm, |
2623 | address & huge_page_mask(h), | |
2624 | (address & huge_page_mask(h)) + huge_page_size(h)); | |
8fe627ec | 2625 | huge_ptep_clear_flush(vma, address, ptep); |
1e8f889b DG |
2626 | set_huge_pte_at(mm, address, ptep, |
2627 | make_huge_pte(vma, new_page, 1)); | |
0fe6e20b | 2628 | page_remove_rmap(old_page); |
cd67f0d2 | 2629 | hugepage_add_new_anon_rmap(new_page, vma, address); |
1e8f889b DG |
2630 | /* Make the old page be freed below */ |
2631 | new_page = old_page; | |
3edd4fc9 DD |
2632 | mmu_notifier_invalidate_range_end(mm, |
2633 | address & huge_page_mask(h), | |
2634 | (address & huge_page_mask(h)) + huge_page_size(h)); | |
1e8f889b DG |
2635 | } |
2636 | page_cache_release(new_page); | |
2637 | page_cache_release(old_page); | |
83c54070 | 2638 | return 0; |
1e8f889b DG |
2639 | } |
2640 | ||
04f2cbe3 | 2641 | /* Return the pagecache page at a given address within a VMA */ |
a5516438 AK |
2642 | static struct page *hugetlbfs_pagecache_page(struct hstate *h, |
2643 | struct vm_area_struct *vma, unsigned long address) | |
04f2cbe3 MG |
2644 | { |
2645 | struct address_space *mapping; | |
e7c4b0bf | 2646 | pgoff_t idx; |
04f2cbe3 MG |
2647 | |
2648 | mapping = vma->vm_file->f_mapping; | |
a5516438 | 2649 | idx = vma_hugecache_offset(h, vma, address); |
04f2cbe3 MG |
2650 | |
2651 | return find_lock_page(mapping, idx); | |
2652 | } | |
2653 | ||
3ae77f43 HD |
2654 | /* |
2655 | * Return whether there is a pagecache page to back given address within VMA. | |
2656 | * Caller follow_hugetlb_page() holds page_table_lock so we cannot lock_page. | |
2657 | */ | |
2658 | static bool hugetlbfs_pagecache_present(struct hstate *h, | |
2a15efc9 HD |
2659 | struct vm_area_struct *vma, unsigned long address) |
2660 | { | |
2661 | struct address_space *mapping; | |
2662 | pgoff_t idx; | |
2663 | struct page *page; | |
2664 | ||
2665 | mapping = vma->vm_file->f_mapping; | |
2666 | idx = vma_hugecache_offset(h, vma, address); | |
2667 | ||
2668 | page = find_get_page(mapping, idx); | |
2669 | if (page) | |
2670 | put_page(page); | |
2671 | return page != NULL; | |
2672 | } | |
2673 | ||
a1ed3dda | 2674 | static int hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma, |
788c7df4 | 2675 | unsigned long address, pte_t *ptep, unsigned int flags) |
ac9b9c66 | 2676 | { |
a5516438 | 2677 | struct hstate *h = hstate_vma(vma); |
ac9b9c66 | 2678 | int ret = VM_FAULT_SIGBUS; |
409eb8c2 | 2679 | int anon_rmap = 0; |
e7c4b0bf | 2680 | pgoff_t idx; |
4c887265 | 2681 | unsigned long size; |
4c887265 AL |
2682 | struct page *page; |
2683 | struct address_space *mapping; | |
1e8f889b | 2684 | pte_t new_pte; |
4c887265 | 2685 | |
04f2cbe3 MG |
2686 | /* |
2687 | * Currently, we are forced to kill the process in the event the | |
2688 | * original mapper has unmapped pages from the child due to a failed | |
25985edc | 2689 | * COW. Warn that such a situation has occurred as it may not be obvious |
04f2cbe3 MG |
2690 | */ |
2691 | if (is_vma_resv_set(vma, HPAGE_RESV_UNMAPPED)) { | |
2692 | printk(KERN_WARNING | |
2693 | "PID %d killed due to inadequate hugepage pool\n", | |
2694 | current->pid); | |
2695 | return ret; | |
2696 | } | |
2697 | ||
4c887265 | 2698 | mapping = vma->vm_file->f_mapping; |
a5516438 | 2699 | idx = vma_hugecache_offset(h, vma, address); |
4c887265 AL |
2700 | |
2701 | /* | |
2702 | * Use page lock to guard against racing truncation | |
2703 | * before we get page_table_lock. | |
2704 | */ | |
6bda666a CL |
2705 | retry: |
2706 | page = find_lock_page(mapping, idx); | |
2707 | if (!page) { | |
a5516438 | 2708 | size = i_size_read(mapping->host) >> huge_page_shift(h); |
ebed4bfc HD |
2709 | if (idx >= size) |
2710 | goto out; | |
04f2cbe3 | 2711 | page = alloc_huge_page(vma, address, 0); |
2fc39cec | 2712 | if (IS_ERR(page)) { |
76dcee75 AK |
2713 | ret = PTR_ERR(page); |
2714 | if (ret == -ENOMEM) | |
2715 | ret = VM_FAULT_OOM; | |
2716 | else | |
2717 | ret = VM_FAULT_SIGBUS; | |
6bda666a CL |
2718 | goto out; |
2719 | } | |
47ad8475 | 2720 | clear_huge_page(page, address, pages_per_huge_page(h)); |
0ed361de | 2721 | __SetPageUptodate(page); |
ac9b9c66 | 2722 | |
f83a275d | 2723 | if (vma->vm_flags & VM_MAYSHARE) { |
6bda666a | 2724 | int err; |
45c682a6 | 2725 | struct inode *inode = mapping->host; |
6bda666a CL |
2726 | |
2727 | err = add_to_page_cache(page, mapping, idx, GFP_KERNEL); | |
2728 | if (err) { | |
2729 | put_page(page); | |
6bda666a CL |
2730 | if (err == -EEXIST) |
2731 | goto retry; | |
2732 | goto out; | |
2733 | } | |
45c682a6 KC |
2734 | |
2735 | spin_lock(&inode->i_lock); | |
a5516438 | 2736 | inode->i_blocks += blocks_per_huge_page(h); |
45c682a6 | 2737 | spin_unlock(&inode->i_lock); |
23be7468 | 2738 | } else { |
6bda666a | 2739 | lock_page(page); |
0fe6e20b NH |
2740 | if (unlikely(anon_vma_prepare(vma))) { |
2741 | ret = VM_FAULT_OOM; | |
2742 | goto backout_unlocked; | |
2743 | } | |
409eb8c2 | 2744 | anon_rmap = 1; |
23be7468 | 2745 | } |
0fe6e20b | 2746 | } else { |
998b4382 NH |
2747 | /* |
2748 | * If memory error occurs between mmap() and fault, some process | |
2749 | * don't have hwpoisoned swap entry for errored virtual address. | |
2750 | * So we need to block hugepage fault by PG_hwpoison bit check. | |
2751 | */ | |
2752 | if (unlikely(PageHWPoison(page))) { | |
32f84528 | 2753 | ret = VM_FAULT_HWPOISON | |
972dc4de | 2754 | VM_FAULT_SET_HINDEX(hstate_index(h)); |
998b4382 NH |
2755 | goto backout_unlocked; |
2756 | } | |
6bda666a | 2757 | } |
1e8f889b | 2758 | |
57303d80 AW |
2759 | /* |
2760 | * If we are going to COW a private mapping later, we examine the | |
2761 | * pending reservations for this page now. This will ensure that | |
2762 | * any allocations necessary to record that reservation occur outside | |
2763 | * the spinlock. | |
2764 | */ | |
788c7df4 | 2765 | if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) |
2b26736c AW |
2766 | if (vma_needs_reservation(h, vma, address) < 0) { |
2767 | ret = VM_FAULT_OOM; | |
2768 | goto backout_unlocked; | |
2769 | } | |
57303d80 | 2770 | |
ac9b9c66 | 2771 | spin_lock(&mm->page_table_lock); |
a5516438 | 2772 | size = i_size_read(mapping->host) >> huge_page_shift(h); |
4c887265 AL |
2773 | if (idx >= size) |
2774 | goto backout; | |
2775 | ||
83c54070 | 2776 | ret = 0; |
7f2e9525 | 2777 | if (!huge_pte_none(huge_ptep_get(ptep))) |
4c887265 AL |
2778 | goto backout; |
2779 | ||
409eb8c2 HD |
2780 | if (anon_rmap) |
2781 | hugepage_add_new_anon_rmap(page, vma, address); | |
2782 | else | |
2783 | page_dup_rmap(page); | |
1e8f889b DG |
2784 | new_pte = make_huge_pte(vma, page, ((vma->vm_flags & VM_WRITE) |
2785 | && (vma->vm_flags & VM_SHARED))); | |
2786 | set_huge_pte_at(mm, address, ptep, new_pte); | |
2787 | ||
788c7df4 | 2788 | if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) { |
1e8f889b | 2789 | /* Optimization, do the COW without a second fault */ |
04f2cbe3 | 2790 | ret = hugetlb_cow(mm, vma, address, ptep, new_pte, page); |
1e8f889b DG |
2791 | } |
2792 | ||
ac9b9c66 | 2793 | spin_unlock(&mm->page_table_lock); |
4c887265 AL |
2794 | unlock_page(page); |
2795 | out: | |
ac9b9c66 | 2796 | return ret; |
4c887265 AL |
2797 | |
2798 | backout: | |
2799 | spin_unlock(&mm->page_table_lock); | |
2b26736c | 2800 | backout_unlocked: |
4c887265 AL |
2801 | unlock_page(page); |
2802 | put_page(page); | |
2803 | goto out; | |
ac9b9c66 HD |
2804 | } |
2805 | ||
86e5216f | 2806 | int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, |
788c7df4 | 2807 | unsigned long address, unsigned int flags) |
86e5216f AL |
2808 | { |
2809 | pte_t *ptep; | |
2810 | pte_t entry; | |
1e8f889b | 2811 | int ret; |
0fe6e20b | 2812 | struct page *page = NULL; |
57303d80 | 2813 | struct page *pagecache_page = NULL; |
3935baa9 | 2814 | static DEFINE_MUTEX(hugetlb_instantiation_mutex); |
a5516438 | 2815 | struct hstate *h = hstate_vma(vma); |
86e5216f | 2816 | |
1e16a539 KH |
2817 | address &= huge_page_mask(h); |
2818 | ||
fd6a03ed NH |
2819 | ptep = huge_pte_offset(mm, address); |
2820 | if (ptep) { | |
2821 | entry = huge_ptep_get(ptep); | |
290408d4 NH |
2822 | if (unlikely(is_hugetlb_entry_migration(entry))) { |
2823 | migration_entry_wait(mm, (pmd_t *)ptep, address); | |
2824 | return 0; | |
2825 | } else if (unlikely(is_hugetlb_entry_hwpoisoned(entry))) | |
32f84528 | 2826 | return VM_FAULT_HWPOISON_LARGE | |
972dc4de | 2827 | VM_FAULT_SET_HINDEX(hstate_index(h)); |
fd6a03ed NH |
2828 | } |
2829 | ||
a5516438 | 2830 | ptep = huge_pte_alloc(mm, address, huge_page_size(h)); |
86e5216f AL |
2831 | if (!ptep) |
2832 | return VM_FAULT_OOM; | |
2833 | ||
3935baa9 DG |
2834 | /* |
2835 | * Serialize hugepage allocation and instantiation, so that we don't | |
2836 | * get spurious allocation failures if two CPUs race to instantiate | |
2837 | * the same page in the page cache. | |
2838 | */ | |
2839 | mutex_lock(&hugetlb_instantiation_mutex); | |
7f2e9525 GS |
2840 | entry = huge_ptep_get(ptep); |
2841 | if (huge_pte_none(entry)) { | |
788c7df4 | 2842 | ret = hugetlb_no_page(mm, vma, address, ptep, flags); |
b4d1d99f | 2843 | goto out_mutex; |
3935baa9 | 2844 | } |
86e5216f | 2845 | |
83c54070 | 2846 | ret = 0; |
1e8f889b | 2847 | |
57303d80 AW |
2848 | /* |
2849 | * If we are going to COW the mapping later, we examine the pending | |
2850 | * reservations for this page now. This will ensure that any | |
2851 | * allocations necessary to record that reservation occur outside the | |
2852 | * spinlock. For private mappings, we also lookup the pagecache | |
2853 | * page now as it is used to determine if a reservation has been | |
2854 | * consumed. | |
2855 | */ | |
788c7df4 | 2856 | if ((flags & FAULT_FLAG_WRITE) && !pte_write(entry)) { |
2b26736c AW |
2857 | if (vma_needs_reservation(h, vma, address) < 0) { |
2858 | ret = VM_FAULT_OOM; | |
b4d1d99f | 2859 | goto out_mutex; |
2b26736c | 2860 | } |
57303d80 | 2861 | |
f83a275d | 2862 | if (!(vma->vm_flags & VM_MAYSHARE)) |
57303d80 AW |
2863 | pagecache_page = hugetlbfs_pagecache_page(h, |
2864 | vma, address); | |
2865 | } | |
2866 | ||
56c9cfb1 NH |
2867 | /* |
2868 | * hugetlb_cow() requires page locks of pte_page(entry) and | |
2869 | * pagecache_page, so here we need take the former one | |
2870 | * when page != pagecache_page or !pagecache_page. | |
2871 | * Note that locking order is always pagecache_page -> page, | |
2872 | * so no worry about deadlock. | |
2873 | */ | |
2874 | page = pte_page(entry); | |
66aebce7 | 2875 | get_page(page); |
56c9cfb1 | 2876 | if (page != pagecache_page) |
0fe6e20b | 2877 | lock_page(page); |
0fe6e20b | 2878 | |
1e8f889b DG |
2879 | spin_lock(&mm->page_table_lock); |
2880 | /* Check for a racing update before calling hugetlb_cow */ | |
b4d1d99f DG |
2881 | if (unlikely(!pte_same(entry, huge_ptep_get(ptep)))) |
2882 | goto out_page_table_lock; | |
2883 | ||
2884 | ||
788c7df4 | 2885 | if (flags & FAULT_FLAG_WRITE) { |
b4d1d99f | 2886 | if (!pte_write(entry)) { |
57303d80 AW |
2887 | ret = hugetlb_cow(mm, vma, address, ptep, entry, |
2888 | pagecache_page); | |
b4d1d99f DG |
2889 | goto out_page_table_lock; |
2890 | } | |
2891 | entry = pte_mkdirty(entry); | |
2892 | } | |
2893 | entry = pte_mkyoung(entry); | |
788c7df4 HD |
2894 | if (huge_ptep_set_access_flags(vma, address, ptep, entry, |
2895 | flags & FAULT_FLAG_WRITE)) | |
4b3073e1 | 2896 | update_mmu_cache(vma, address, ptep); |
b4d1d99f DG |
2897 | |
2898 | out_page_table_lock: | |
1e8f889b | 2899 | spin_unlock(&mm->page_table_lock); |
57303d80 AW |
2900 | |
2901 | if (pagecache_page) { | |
2902 | unlock_page(pagecache_page); | |
2903 | put_page(pagecache_page); | |
2904 | } | |
1f64d69c DN |
2905 | if (page != pagecache_page) |
2906 | unlock_page(page); | |
66aebce7 | 2907 | put_page(page); |
57303d80 | 2908 | |
b4d1d99f | 2909 | out_mutex: |
3935baa9 | 2910 | mutex_unlock(&hugetlb_instantiation_mutex); |
1e8f889b DG |
2911 | |
2912 | return ret; | |
86e5216f AL |
2913 | } |
2914 | ||
ceb86879 AK |
2915 | /* Can be overriden by architectures */ |
2916 | __attribute__((weak)) struct page * | |
2917 | follow_huge_pud(struct mm_struct *mm, unsigned long address, | |
2918 | pud_t *pud, int write) | |
2919 | { | |
2920 | BUG(); | |
2921 | return NULL; | |
2922 | } | |
2923 | ||
63551ae0 DG |
2924 | int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, |
2925 | struct page **pages, struct vm_area_struct **vmas, | |
5b23dbe8 | 2926 | unsigned long *position, int *length, int i, |
2a15efc9 | 2927 | unsigned int flags) |
63551ae0 | 2928 | { |
d5d4b0aa CK |
2929 | unsigned long pfn_offset; |
2930 | unsigned long vaddr = *position; | |
63551ae0 | 2931 | int remainder = *length; |
a5516438 | 2932 | struct hstate *h = hstate_vma(vma); |
63551ae0 | 2933 | |
1c59827d | 2934 | spin_lock(&mm->page_table_lock); |
63551ae0 | 2935 | while (vaddr < vma->vm_end && remainder) { |
4c887265 | 2936 | pte_t *pte; |
2a15efc9 | 2937 | int absent; |
4c887265 | 2938 | struct page *page; |
63551ae0 | 2939 | |
4c887265 AL |
2940 | /* |
2941 | * Some archs (sparc64, sh*) have multiple pte_ts to | |
2a15efc9 | 2942 | * each hugepage. We have to make sure we get the |
4c887265 AL |
2943 | * first, for the page indexing below to work. |
2944 | */ | |
a5516438 | 2945 | pte = huge_pte_offset(mm, vaddr & huge_page_mask(h)); |
2a15efc9 HD |
2946 | absent = !pte || huge_pte_none(huge_ptep_get(pte)); |
2947 | ||
2948 | /* | |
2949 | * When coredumping, it suits get_dump_page if we just return | |
3ae77f43 HD |
2950 | * an error where there's an empty slot with no huge pagecache |
2951 | * to back it. This way, we avoid allocating a hugepage, and | |
2952 | * the sparse dumpfile avoids allocating disk blocks, but its | |
2953 | * huge holes still show up with zeroes where they need to be. | |
2a15efc9 | 2954 | */ |
3ae77f43 HD |
2955 | if (absent && (flags & FOLL_DUMP) && |
2956 | !hugetlbfs_pagecache_present(h, vma, vaddr)) { | |
2a15efc9 HD |
2957 | remainder = 0; |
2958 | break; | |
2959 | } | |
63551ae0 | 2960 | |
2a15efc9 HD |
2961 | if (absent || |
2962 | ((flags & FOLL_WRITE) && !pte_write(huge_ptep_get(pte)))) { | |
4c887265 | 2963 | int ret; |
63551ae0 | 2964 | |
4c887265 | 2965 | spin_unlock(&mm->page_table_lock); |
2a15efc9 HD |
2966 | ret = hugetlb_fault(mm, vma, vaddr, |
2967 | (flags & FOLL_WRITE) ? FAULT_FLAG_WRITE : 0); | |
4c887265 | 2968 | spin_lock(&mm->page_table_lock); |
a89182c7 | 2969 | if (!(ret & VM_FAULT_ERROR)) |
4c887265 | 2970 | continue; |
63551ae0 | 2971 | |
4c887265 | 2972 | remainder = 0; |
4c887265 AL |
2973 | break; |
2974 | } | |
2975 | ||
a5516438 | 2976 | pfn_offset = (vaddr & ~huge_page_mask(h)) >> PAGE_SHIFT; |
7f2e9525 | 2977 | page = pte_page(huge_ptep_get(pte)); |
d5d4b0aa | 2978 | same_page: |
d6692183 | 2979 | if (pages) { |
2a15efc9 | 2980 | pages[i] = mem_map_offset(page, pfn_offset); |
4b2e38ad | 2981 | get_page(pages[i]); |
d6692183 | 2982 | } |
63551ae0 DG |
2983 | |
2984 | if (vmas) | |
2985 | vmas[i] = vma; | |
2986 | ||
2987 | vaddr += PAGE_SIZE; | |
d5d4b0aa | 2988 | ++pfn_offset; |
63551ae0 DG |
2989 | --remainder; |
2990 | ++i; | |
d5d4b0aa | 2991 | if (vaddr < vma->vm_end && remainder && |
a5516438 | 2992 | pfn_offset < pages_per_huge_page(h)) { |
d5d4b0aa CK |
2993 | /* |
2994 | * We use pfn_offset to avoid touching the pageframes | |
2995 | * of this compound page. | |
2996 | */ | |
2997 | goto same_page; | |
2998 | } | |
63551ae0 | 2999 | } |
1c59827d | 3000 | spin_unlock(&mm->page_table_lock); |
63551ae0 DG |
3001 | *length = remainder; |
3002 | *position = vaddr; | |
3003 | ||
2a15efc9 | 3004 | return i ? i : -EFAULT; |
63551ae0 | 3005 | } |
8f860591 ZY |
3006 | |
3007 | void hugetlb_change_protection(struct vm_area_struct *vma, | |
3008 | unsigned long address, unsigned long end, pgprot_t newprot) | |
3009 | { | |
3010 | struct mm_struct *mm = vma->vm_mm; | |
3011 | unsigned long start = address; | |
3012 | pte_t *ptep; | |
3013 | pte_t pte; | |
a5516438 | 3014 | struct hstate *h = hstate_vma(vma); |
8f860591 ZY |
3015 | |
3016 | BUG_ON(address >= end); | |
3017 | flush_cache_range(vma, address, end); | |
3018 | ||
3d48ae45 | 3019 | mutex_lock(&vma->vm_file->f_mapping->i_mmap_mutex); |
8f860591 | 3020 | spin_lock(&mm->page_table_lock); |
a5516438 | 3021 | for (; address < end; address += huge_page_size(h)) { |
8f860591 ZY |
3022 | ptep = huge_pte_offset(mm, address); |
3023 | if (!ptep) | |
3024 | continue; | |
39dde65c CK |
3025 | if (huge_pmd_unshare(mm, &address, ptep)) |
3026 | continue; | |
7f2e9525 | 3027 | if (!huge_pte_none(huge_ptep_get(ptep))) { |
8f860591 ZY |
3028 | pte = huge_ptep_get_and_clear(mm, address, ptep); |
3029 | pte = pte_mkhuge(pte_modify(pte, newprot)); | |
3030 | set_huge_pte_at(mm, address, ptep, pte); | |
8f860591 ZY |
3031 | } |
3032 | } | |
3033 | spin_unlock(&mm->page_table_lock); | |
d833352a MG |
3034 | /* |
3035 | * Must flush TLB before releasing i_mmap_mutex: x86's huge_pmd_unshare | |
3036 | * may have cleared our pud entry and done put_page on the page table: | |
3037 | * once we release i_mmap_mutex, another task can do the final put_page | |
3038 | * and that page table be reused and filled with junk. | |
3039 | */ | |
8f860591 | 3040 | flush_tlb_range(vma, start, end); |
d833352a | 3041 | mutex_unlock(&vma->vm_file->f_mapping->i_mmap_mutex); |
8f860591 ZY |
3042 | } |
3043 | ||
a1e78772 MG |
3044 | int hugetlb_reserve_pages(struct inode *inode, |
3045 | long from, long to, | |
5a6fe125 | 3046 | struct vm_area_struct *vma, |
ca16d140 | 3047 | vm_flags_t vm_flags) |
e4e574b7 | 3048 | { |
17c9d12e | 3049 | long ret, chg; |
a5516438 | 3050 | struct hstate *h = hstate_inode(inode); |
90481622 | 3051 | struct hugepage_subpool *spool = subpool_inode(inode); |
e4e574b7 | 3052 | |
17c9d12e MG |
3053 | /* |
3054 | * Only apply hugepage reservation if asked. At fault time, an | |
3055 | * attempt will be made for VM_NORESERVE to allocate a page | |
90481622 | 3056 | * without using reserves |
17c9d12e | 3057 | */ |
ca16d140 | 3058 | if (vm_flags & VM_NORESERVE) |
17c9d12e MG |
3059 | return 0; |
3060 | ||
a1e78772 MG |
3061 | /* |
3062 | * Shared mappings base their reservation on the number of pages that | |
3063 | * are already allocated on behalf of the file. Private mappings need | |
3064 | * to reserve the full area even if read-only as mprotect() may be | |
3065 | * called to make the mapping read-write. Assume !vma is a shm mapping | |
3066 | */ | |
f83a275d | 3067 | if (!vma || vma->vm_flags & VM_MAYSHARE) |
a1e78772 | 3068 | chg = region_chg(&inode->i_mapping->private_list, from, to); |
17c9d12e MG |
3069 | else { |
3070 | struct resv_map *resv_map = resv_map_alloc(); | |
3071 | if (!resv_map) | |
3072 | return -ENOMEM; | |
3073 | ||
a1e78772 | 3074 | chg = to - from; |
84afd99b | 3075 | |
17c9d12e MG |
3076 | set_vma_resv_map(vma, resv_map); |
3077 | set_vma_resv_flags(vma, HPAGE_RESV_OWNER); | |
3078 | } | |
3079 | ||
c50ac050 DH |
3080 | if (chg < 0) { |
3081 | ret = chg; | |
3082 | goto out_err; | |
3083 | } | |
8a630112 | 3084 | |
90481622 | 3085 | /* There must be enough pages in the subpool for the mapping */ |
c50ac050 DH |
3086 | if (hugepage_subpool_get_pages(spool, chg)) { |
3087 | ret = -ENOSPC; | |
3088 | goto out_err; | |
3089 | } | |
5a6fe125 MG |
3090 | |
3091 | /* | |
17c9d12e | 3092 | * Check enough hugepages are available for the reservation. |
90481622 | 3093 | * Hand the pages back to the subpool if there are not |
5a6fe125 | 3094 | */ |
a5516438 | 3095 | ret = hugetlb_acct_memory(h, chg); |
68842c9b | 3096 | if (ret < 0) { |
90481622 | 3097 | hugepage_subpool_put_pages(spool, chg); |
c50ac050 | 3098 | goto out_err; |
68842c9b | 3099 | } |
17c9d12e MG |
3100 | |
3101 | /* | |
3102 | * Account for the reservations made. Shared mappings record regions | |
3103 | * that have reservations as they are shared by multiple VMAs. | |
3104 | * When the last VMA disappears, the region map says how much | |
3105 | * the reservation was and the page cache tells how much of | |
3106 | * the reservation was consumed. Private mappings are per-VMA and | |
3107 | * only the consumed reservations are tracked. When the VMA | |
3108 | * disappears, the original reservation is the VMA size and the | |
3109 | * consumed reservations are stored in the map. Hence, nothing | |
3110 | * else has to be done for private mappings here | |
3111 | */ | |
f83a275d | 3112 | if (!vma || vma->vm_flags & VM_MAYSHARE) |
a1e78772 | 3113 | region_add(&inode->i_mapping->private_list, from, to); |
a43a8c39 | 3114 | return 0; |
c50ac050 | 3115 | out_err: |
4523e145 DH |
3116 | if (vma) |
3117 | resv_map_put(vma); | |
c50ac050 | 3118 | return ret; |
a43a8c39 CK |
3119 | } |
3120 | ||
3121 | void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed) | |
3122 | { | |
a5516438 | 3123 | struct hstate *h = hstate_inode(inode); |
a43a8c39 | 3124 | long chg = region_truncate(&inode->i_mapping->private_list, offset); |
90481622 | 3125 | struct hugepage_subpool *spool = subpool_inode(inode); |
45c682a6 KC |
3126 | |
3127 | spin_lock(&inode->i_lock); | |
e4c6f8be | 3128 | inode->i_blocks -= (blocks_per_huge_page(h) * freed); |
45c682a6 KC |
3129 | spin_unlock(&inode->i_lock); |
3130 | ||
90481622 | 3131 | hugepage_subpool_put_pages(spool, (chg - freed)); |
a5516438 | 3132 | hugetlb_acct_memory(h, -(chg - freed)); |
a43a8c39 | 3133 | } |
93f70f90 | 3134 | |
d5bd9106 AK |
3135 | #ifdef CONFIG_MEMORY_FAILURE |
3136 | ||
6de2b1aa NH |
3137 | /* Should be called in hugetlb_lock */ |
3138 | static int is_hugepage_on_freelist(struct page *hpage) | |
3139 | { | |
3140 | struct page *page; | |
3141 | struct page *tmp; | |
3142 | struct hstate *h = page_hstate(hpage); | |
3143 | int nid = page_to_nid(hpage); | |
3144 | ||
3145 | list_for_each_entry_safe(page, tmp, &h->hugepage_freelists[nid], lru) | |
3146 | if (page == hpage) | |
3147 | return 1; | |
3148 | return 0; | |
3149 | } | |
3150 | ||
93f70f90 NH |
3151 | /* |
3152 | * This function is called from memory failure code. | |
3153 | * Assume the caller holds page lock of the head page. | |
3154 | */ | |
6de2b1aa | 3155 | int dequeue_hwpoisoned_huge_page(struct page *hpage) |
93f70f90 NH |
3156 | { |
3157 | struct hstate *h = page_hstate(hpage); | |
3158 | int nid = page_to_nid(hpage); | |
6de2b1aa | 3159 | int ret = -EBUSY; |
93f70f90 NH |
3160 | |
3161 | spin_lock(&hugetlb_lock); | |
6de2b1aa NH |
3162 | if (is_hugepage_on_freelist(hpage)) { |
3163 | list_del(&hpage->lru); | |
8c6c2ecb | 3164 | set_page_refcounted(hpage); |
6de2b1aa NH |
3165 | h->free_huge_pages--; |
3166 | h->free_huge_pages_node[nid]--; | |
3167 | ret = 0; | |
3168 | } | |
93f70f90 | 3169 | spin_unlock(&hugetlb_lock); |
6de2b1aa | 3170 | return ret; |
93f70f90 | 3171 | } |
6de2b1aa | 3172 | #endif |