1
2
3
4
5#include <linux/gfp.h>
6#include <linux/list.h>
7#include <linux/init.h>
8#include <linux/module.h>
9#include <linux/mm.h>
10#include <linux/seq_file.h>
11#include <linux/sysctl.h>
12#include <linux/highmem.h>
13#include <linux/mmu_notifier.h>
14#include <linux/nodemask.h>
15#include <linux/pagemap.h>
16#include <linux/mempolicy.h>
17#include <linux/cpuset.h>
18#include <linux/mutex.h>
19#include <linux/bootmem.h>
20#include <linux/sysfs.h>
21
22#include <asm/page.h>
23#include <asm/pgtable.h>
24#include <asm/io.h>
25
26#include <linux/hugetlb.h>
27#include "internal.h"
28
29const unsigned long hugetlb_zero = 0, hugetlb_infinity = ~0UL;
30static gfp_t htlb_alloc_mask = GFP_HIGHUSER;
31unsigned long hugepages_treat_as_movable;
32
33static int max_hstate;
34unsigned int default_hstate_idx;
35struct hstate hstates[HUGE_MAX_HSTATE];
36
37__initdata LIST_HEAD(huge_boot_pages);
38
39
40static struct hstate * __initdata parsed_hstate;
41static unsigned long __initdata default_hstate_max_huge_pages;
42static unsigned long __initdata default_hstate_size;
43
44#define for_each_hstate(h) \
45 for ((h) = hstates; (h) < &hstates[max_hstate]; (h)++)
46
47
48
49
50static DEFINE_SPINLOCK(hugetlb_lock);
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66struct file_region {
67 struct list_head link;
68 long from;
69 long to;
70};
71
72static long region_add(struct list_head *head, long f, long t)
73{
74 struct file_region *rg, *nrg, *trg;
75
76
77 list_for_each_entry(rg, head, link)
78 if (f <= rg->to)
79 break;
80
81
82 if (f > rg->from)
83 f = rg->from;
84
85
86 nrg = rg;
87 list_for_each_entry_safe(rg, trg, rg->link.prev, link) {
88 if (&rg->link == head)
89 break;
90 if (rg->from > t)
91 break;
92
93
94
95
96 if (rg->to > t)
97 t = rg->to;
98 if (rg != nrg) {
99 list_del(&rg->link);
100 kfree(rg);
101 }
102 }
103 nrg->from = f;
104 nrg->to = t;
105 return 0;
106}
107
108static long region_chg(struct list_head *head, long f, long t)
109{
110 struct file_region *rg, *nrg;
111 long chg = 0;
112
113
114 list_for_each_entry(rg, head, link)
115 if (f <= rg->to)
116 break;
117
118
119
120
121 if (&rg->link == head || t < rg->from) {
122 nrg = kmalloc(sizeof(*nrg), GFP_KERNEL);
123 if (!nrg)
124 return -ENOMEM;
125 nrg->from = f;
126 nrg->to = f;
127 INIT_LIST_HEAD(&nrg->link);
128 list_add(&nrg->link, rg->link.prev);
129
130 return t - f;
131 }
132
133
134 if (f > rg->from)
135 f = rg->from;
136 chg = t - f;
137
138
139 list_for_each_entry(rg, rg->link.prev, link) {
140 if (&rg->link == head)
141 break;
142 if (rg->from > t)
143 return chg;
144
145
146
147
148 if (rg->to > t) {
149 chg += rg->to - t;
150 t = rg->to;
151 }
152 chg -= rg->to - rg->from;
153 }
154 return chg;
155}
156
157static long region_truncate(struct list_head *head, long end)
158{
159 struct file_region *rg, *trg;
160 long chg = 0;
161
162
163 list_for_each_entry(rg, head, link)
164 if (end <= rg->to)
165 break;
166 if (&rg->link == head)
167 return 0;
168
169
170 if (end > rg->from) {
171 chg = rg->to - end;
172 rg->to = end;
173 rg = list_entry(rg->link.next, typeof(*rg), link);
174 }
175
176
177 list_for_each_entry_safe(rg, trg, rg->link.prev, link) {
178 if (&rg->link == head)
179 break;
180 chg += rg->to - rg->from;
181 list_del(&rg->link);
182 kfree(rg);
183 }
184 return chg;
185}
186
187static long region_count(struct list_head *head, long f, long t)
188{
189 struct file_region *rg;
190 long chg = 0;
191
192
193 list_for_each_entry(rg, head, link) {
194 int seg_from;
195 int seg_to;
196
197 if (rg->to <= f)
198 continue;
199 if (rg->from >= t)
200 break;
201
202 seg_from = max(rg->from, f);
203 seg_to = min(rg->to, t);
204
205 chg += seg_to - seg_from;
206 }
207
208 return chg;
209}
210
211
212
213
214
215static pgoff_t vma_hugecache_offset(struct hstate *h,
216 struct vm_area_struct *vma, unsigned long address)
217{
218 return ((address - vma->vm_start) >> huge_page_shift(h)) +
219 (vma->vm_pgoff >> huge_page_order(h));
220}
221
222
223
224
225
226
227#define HPAGE_RESV_OWNER (1UL << 0)
228#define HPAGE_RESV_UNMAPPED (1UL << 1)
229#define HPAGE_RESV_MASK (HPAGE_RESV_OWNER | HPAGE_RESV_UNMAPPED)
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250static unsigned long get_vma_private_data(struct vm_area_struct *vma)
251{
252 return (unsigned long)vma->vm_private_data;
253}
254
255static void set_vma_private_data(struct vm_area_struct *vma,
256 unsigned long value)
257{
258 vma->vm_private_data = (void *)value;
259}
260
261struct resv_map {
262 struct kref refs;
263 struct list_head regions;
264};
265
266static struct resv_map *resv_map_alloc(void)
267{
268 struct resv_map *resv_map = kmalloc(sizeof(*resv_map), GFP_KERNEL);
269 if (!resv_map)
270 return NULL;
271
272 kref_init(&resv_map->refs);
273 INIT_LIST_HEAD(&resv_map->regions);
274
275 return resv_map;
276}
277
278static void resv_map_release(struct kref *ref)
279{
280 struct resv_map *resv_map = container_of(ref, struct resv_map, refs);
281
282
283 region_truncate(&resv_map->regions, 0);
284 kfree(resv_map);
285}
286
287static struct resv_map *vma_resv_map(struct vm_area_struct *vma)
288{
289 VM_BUG_ON(!is_vm_hugetlb_page(vma));
290 if (!(vma->vm_flags & VM_SHARED))
291 return (struct resv_map *)(get_vma_private_data(vma) &
292 ~HPAGE_RESV_MASK);
293 return NULL;
294}
295
296static void set_vma_resv_map(struct vm_area_struct *vma, struct resv_map *map)
297{
298 VM_BUG_ON(!is_vm_hugetlb_page(vma));
299 VM_BUG_ON(vma->vm_flags & VM_SHARED);
300
301 set_vma_private_data(vma, (get_vma_private_data(vma) &
302 HPAGE_RESV_MASK) | (unsigned long)map);
303}
304
305static void set_vma_resv_flags(struct vm_area_struct *vma, unsigned long flags)
306{
307 VM_BUG_ON(!is_vm_hugetlb_page(vma));
308 VM_BUG_ON(vma->vm_flags & VM_SHARED);
309
310 set_vma_private_data(vma, get_vma_private_data(vma) | flags);
311}
312
313static int is_vma_resv_set(struct vm_area_struct *vma, unsigned long flag)
314{
315 VM_BUG_ON(!is_vm_hugetlb_page(vma));
316
317 return (get_vma_private_data(vma) & flag) != 0;
318}
319
320
321static void decrement_hugepage_resv_vma(struct hstate *h,
322 struct vm_area_struct *vma)
323{
324 if (vma->vm_flags & VM_NORESERVE)
325 return;
326
327 if (vma->vm_flags & VM_SHARED) {
328
329 h->resv_huge_pages--;
330 } else if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) {
331
332
333
334
335 h->resv_huge_pages--;
336 }
337}
338
339
340void reset_vma_resv_huge_pages(struct vm_area_struct *vma)
341{
342 VM_BUG_ON(!is_vm_hugetlb_page(vma));
343 if (!(vma->vm_flags & VM_SHARED))
344 vma->vm_private_data = (void *)0;
345}
346
347
348static int vma_has_reserves(struct vm_area_struct *vma)
349{
350 if (vma->vm_flags & VM_SHARED)
351 return 1;
352 if (is_vma_resv_set(vma, HPAGE_RESV_OWNER))
353 return 1;
354 return 0;
355}
356
357static void clear_gigantic_page(struct page *page,
358 unsigned long addr, unsigned long sz)
359{
360 int i;
361 struct page *p = page;
362
363 might_sleep();
364 for (i = 0; i < sz/PAGE_SIZE; i++, p = mem_map_next(p, page, i)) {
365 cond_resched();
366 clear_user_highpage(p, addr + i * PAGE_SIZE);
367 }
368}
369static void clear_huge_page(struct page *page,
370 unsigned long addr, unsigned long sz)
371{
372 int i;
373
374 if (unlikely(sz > MAX_ORDER_NR_PAGES))
375 return clear_gigantic_page(page, addr, sz);
376
377 might_sleep();
378 for (i = 0; i < sz/PAGE_SIZE; i++) {
379 cond_resched();
380 clear_user_highpage(page + i, addr + i * PAGE_SIZE);
381 }
382}
383
384static void copy_gigantic_page(struct page *dst, struct page *src,
385 unsigned long addr, struct vm_area_struct *vma)
386{
387 int i;
388 struct hstate *h = hstate_vma(vma);
389 struct page *dst_base = dst;
390 struct page *src_base = src;
391 might_sleep();
392 for (i = 0; i < pages_per_huge_page(h); ) {
393 cond_resched();
394 copy_user_highpage(dst, src, addr + i*PAGE_SIZE, vma);
395
396 i++;
397 dst = mem_map_next(dst, dst_base, i);
398 src = mem_map_next(src, src_base, i);
399 }
400}
401static void copy_huge_page(struct page *dst, struct page *src,
402 unsigned long addr, struct vm_area_struct *vma)
403{
404 int i;
405 struct hstate *h = hstate_vma(vma);
406
407 if (unlikely(pages_per_huge_page(h) > MAX_ORDER_NR_PAGES))
408 return copy_gigantic_page(dst, src, addr, vma);
409
410 might_sleep();
411 for (i = 0; i < pages_per_huge_page(h); i++) {
412 cond_resched();
413 copy_user_highpage(dst + i, src + i, addr + i*PAGE_SIZE, vma);
414 }
415}
416
417static void enqueue_huge_page(struct hstate *h, struct page *page)
418{
419 int nid = page_to_nid(page);
420 list_add(&page->lru, &h->hugepage_freelists[nid]);
421 h->free_huge_pages++;
422 h->free_huge_pages_node[nid]++;
423}
424
425static struct page *dequeue_huge_page(struct hstate *h)
426{
427 int nid;
428 struct page *page = NULL;
429
430 for (nid = 0; nid < MAX_NUMNODES; ++nid) {
431 if (!list_empty(&h->hugepage_freelists[nid])) {
432 page = list_entry(h->hugepage_freelists[nid].next,
433 struct page, lru);
434 list_del(&page->lru);
435 h->free_huge_pages--;
436 h->free_huge_pages_node[nid]--;
437 break;
438 }
439 }
440 return page;
441}
442
443static struct page *dequeue_huge_page_vma(struct hstate *h,
444 struct vm_area_struct *vma,
445 unsigned long address, int avoid_reserve)
446{
447 int nid;
448 struct page *page = NULL;
449 struct mempolicy *mpol;
450 nodemask_t *nodemask;
451 struct zonelist *zonelist = huge_zonelist(vma, address,
452 htlb_alloc_mask, &mpol, &nodemask);
453 struct zone *zone;
454 struct zoneref *z;
455
456
457
458
459
460
461 if (!vma_has_reserves(vma) &&
462 h->free_huge_pages - h->resv_huge_pages == 0)
463 return NULL;
464
465
466 if (avoid_reserve && h->free_huge_pages - h->resv_huge_pages == 0)
467 return NULL;
468
469 for_each_zone_zonelist_nodemask(zone, z, zonelist,
470 MAX_NR_ZONES - 1, nodemask) {
471 nid = zone_to_nid(zone);
472 if (cpuset_zone_allowed_softwall(zone, htlb_alloc_mask) &&
473 !list_empty(&h->hugepage_freelists[nid])) {
474 page = list_entry(h->hugepage_freelists[nid].next,
475 struct page, lru);
476 list_del(&page->lru);
477 h->free_huge_pages--;
478 h->free_huge_pages_node[nid]--;
479
480 if (!avoid_reserve)
481 decrement_hugepage_resv_vma(h, vma);
482
483 break;
484 }
485 }
486 mpol_cond_put(mpol);
487 return page;
488}
489
490static void update_and_free_page(struct hstate *h, struct page *page)
491{
492 int i;
493
494 VM_BUG_ON(h->order >= MAX_ORDER);
495
496 h->nr_huge_pages--;
497 h->nr_huge_pages_node[page_to_nid(page)]--;
498 for (i = 0; i < pages_per_huge_page(h); i++) {
499 page[i].flags &= ~(1 << PG_locked | 1 << PG_error | 1 << PG_referenced |
500 1 << PG_dirty | 1 << PG_active | 1 << PG_reserved |
501 1 << PG_private | 1<< PG_writeback);
502 }
503 set_compound_page_dtor(page, NULL);
504 set_page_refcounted(page);
505 arch_release_hugepage(page);
506 __free_pages(page, huge_page_order(h));
507}
508
509struct hstate *size_to_hstate(unsigned long size)
510{
511 struct hstate *h;
512
513 for_each_hstate(h) {
514 if (huge_page_size(h) == size)
515 return h;
516 }
517 return NULL;
518}
519
520static void free_huge_page(struct page *page)
521{
522
523
524
525
526 struct hstate *h = page_hstate(page);
527 int nid = page_to_nid(page);
528 struct address_space *mapping;
529
530 mapping = (struct address_space *) page_private(page);
531 set_page_private(page, 0);
532 BUG_ON(page_count(page));
533 INIT_LIST_HEAD(&page->lru);
534
535 spin_lock(&hugetlb_lock);
536 if (h->surplus_huge_pages_node[nid] && huge_page_order(h) < MAX_ORDER) {
537 update_and_free_page(h, page);
538 h->surplus_huge_pages--;
539 h->surplus_huge_pages_node[nid]--;
540 } else {
541 enqueue_huge_page(h, page);
542 }
543 spin_unlock(&hugetlb_lock);
544 if (mapping)
545 hugetlb_put_quota(mapping, 1);
546}
547
548
549
550
551
552
553static int adjust_pool_surplus(struct hstate *h, int delta)
554{
555 static int prev_nid;
556 int nid = prev_nid;
557 int ret = 0;
558
559 VM_BUG_ON(delta != -1 && delta != 1);
560 do {
561 nid = next_node(nid, node_online_map);
562 if (nid == MAX_NUMNODES)
563 nid = first_node(node_online_map);
564
565
566 if (delta < 0 && !h->surplus_huge_pages_node[nid])
567 continue;
568
569 if (delta > 0 && h->surplus_huge_pages_node[nid] >=
570 h->nr_huge_pages_node[nid])
571 continue;
572
573 h->surplus_huge_pages += delta;
574 h->surplus_huge_pages_node[nid] += delta;
575 ret = 1;
576 break;
577 } while (nid != prev_nid);
578
579 prev_nid = nid;
580 return ret;
581}
582
583static void prep_new_huge_page(struct hstate *h, struct page *page, int nid)
584{
585 set_compound_page_dtor(page, free_huge_page);
586 spin_lock(&hugetlb_lock);
587 h->nr_huge_pages++;
588 h->nr_huge_pages_node[nid]++;
589 spin_unlock(&hugetlb_lock);
590 put_page(page);
591}
592
593static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid)
594{
595 struct page *page;
596
597 if (h->order >= MAX_ORDER)
598 return NULL;
599
600 page = alloc_pages_node(nid,
601 htlb_alloc_mask|__GFP_COMP|__GFP_THISNODE|
602 __GFP_REPEAT|__GFP_NOWARN,
603 huge_page_order(h));
604 if (page) {
605 if (arch_prepare_hugepage(page)) {
606 __free_pages(page, huge_page_order(h));
607 return NULL;
608 }
609 prep_new_huge_page(h, page, nid);
610 }
611
612 return page;
613}
614
615
616
617
618
619
620
621
622
623
624
625
626static int hstate_next_node(struct hstate *h)
627{
628 int next_nid;
629 next_nid = next_node(h->hugetlb_next_nid, node_online_map);
630 if (next_nid == MAX_NUMNODES)
631 next_nid = first_node(node_online_map);
632 h->hugetlb_next_nid = next_nid;
633 return next_nid;
634}
635
636static int alloc_fresh_huge_page(struct hstate *h)
637{
638 struct page *page;
639 int start_nid;
640 int next_nid;
641 int ret = 0;
642
643 start_nid = h->hugetlb_next_nid;
644
645 do {
646 page = alloc_fresh_huge_page_node(h, h->hugetlb_next_nid);
647 if (page)
648 ret = 1;
649 next_nid = hstate_next_node(h);
650 } while (!page && h->hugetlb_next_nid != start_nid);
651
652 if (ret)
653 count_vm_event(HTLB_BUDDY_PGALLOC);
654 else
655 count_vm_event(HTLB_BUDDY_PGALLOC_FAIL);
656
657 return ret;
658}
659
660static struct page *alloc_buddy_huge_page(struct hstate *h,
661 struct vm_area_struct *vma, unsigned long address)
662{
663 struct page *page;
664 unsigned int nid;
665
666 if (h->order >= MAX_ORDER)
667 return NULL;
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692 spin_lock(&hugetlb_lock);
693 if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages) {
694 spin_unlock(&hugetlb_lock);
695 return NULL;
696 } else {
697 h->nr_huge_pages++;
698 h->surplus_huge_pages++;
699 }
700 spin_unlock(&hugetlb_lock);
701
702 page = alloc_pages(htlb_alloc_mask|__GFP_COMP|
703 __GFP_REPEAT|__GFP_NOWARN,
704 huge_page_order(h));
705
706 if (page && arch_prepare_hugepage(page)) {
707 __free_pages(page, huge_page_order(h));
708 return NULL;
709 }
710
711 spin_lock(&hugetlb_lock);
712 if (page) {
713
714
715
716
717 put_page_testzero(page);
718 VM_BUG_ON(page_count(page));
719 nid = page_to_nid(page);
720 set_compound_page_dtor(page, free_huge_page);
721
722
723
724 h->nr_huge_pages_node[nid]++;
725 h->surplus_huge_pages_node[nid]++;
726 __count_vm_event(HTLB_BUDDY_PGALLOC);
727 } else {
728 h->nr_huge_pages--;
729 h->surplus_huge_pages--;
730 __count_vm_event(HTLB_BUDDY_PGALLOC_FAIL);
731 }
732 spin_unlock(&hugetlb_lock);
733
734 return page;
735}
736
737
738
739
740
741static int gather_surplus_pages(struct hstate *h, int delta)
742{
743 struct list_head surplus_list;
744 struct page *page, *tmp;
745 int ret, i;
746 int needed, allocated;
747
748 needed = (h->resv_huge_pages + delta) - h->free_huge_pages;
749 if (needed <= 0) {
750 h->resv_huge_pages += delta;
751 return 0;
752 }
753
754 allocated = 0;
755 INIT_LIST_HEAD(&surplus_list);
756
757 ret = -ENOMEM;
758retry:
759 spin_unlock(&hugetlb_lock);
760 for (i = 0; i < needed; i++) {
761 page = alloc_buddy_huge_page(h, NULL, 0);
762 if (!page) {
763
764
765
766
767
768 spin_lock(&hugetlb_lock);
769 needed = 0;
770 goto free;
771 }
772
773 list_add(&page->lru, &surplus_list);
774 }
775 allocated += needed;
776
777
778
779
780
781 spin_lock(&hugetlb_lock);
782 needed = (h->resv_huge_pages + delta) -
783 (h->free_huge_pages + allocated);
784 if (needed > 0)
785 goto retry;
786
787
788
789
790
791
792
793
794
795 needed += allocated;
796 h->resv_huge_pages += delta;
797 ret = 0;
798free:
799
800 list_for_each_entry_safe(page, tmp, &surplus_list, lru) {
801 if ((--needed) < 0)
802 break;
803 list_del(&page->lru);
804 enqueue_huge_page(h, page);
805 }
806
807
808 if (!list_empty(&surplus_list)) {
809 spin_unlock(&hugetlb_lock);
810 list_for_each_entry_safe(page, tmp, &surplus_list, lru) {
811 list_del(&page->lru);
812
813
814
815
816
817
818
819 free_huge_page(page);
820 }
821 spin_lock(&hugetlb_lock);
822 }
823
824 return ret;
825}
826
827
828
829
830
831
832static void return_unused_surplus_pages(struct hstate *h,
833 unsigned long unused_resv_pages)
834{
835 static int nid = -1;
836 struct page *page;
837 unsigned long nr_pages;
838
839
840
841
842
843
844
845 unsigned long remaining_iterations = num_online_nodes();
846
847
848 h->resv_huge_pages -= unused_resv_pages;
849
850
851 if (h->order >= MAX_ORDER)
852 return;
853
854 nr_pages = min(unused_resv_pages, h->surplus_huge_pages);
855
856 while (remaining_iterations-- && nr_pages) {
857 nid = next_node(nid, node_online_map);
858 if (nid == MAX_NUMNODES)
859 nid = first_node(node_online_map);
860
861 if (!h->surplus_huge_pages_node[nid])
862 continue;
863
864 if (!list_empty(&h->hugepage_freelists[nid])) {
865 page = list_entry(h->hugepage_freelists[nid].next,
866 struct page, lru);
867 list_del(&page->lru);
868 update_and_free_page(h, page);
869 h->free_huge_pages--;
870 h->free_huge_pages_node[nid]--;
871 h->surplus_huge_pages--;
872 h->surplus_huge_pages_node[nid]--;
873 nr_pages--;
874 remaining_iterations = num_online_nodes();
875 }
876 }
877}
878
879
880
881
882
883
884
885
886
887
888static int vma_needs_reservation(struct hstate *h,
889 struct vm_area_struct *vma, unsigned long addr)
890{
891 struct address_space *mapping = vma->vm_file->f_mapping;
892 struct inode *inode = mapping->host;
893
894 if (vma->vm_flags & VM_SHARED) {
895 pgoff_t idx = vma_hugecache_offset(h, vma, addr);
896 return region_chg(&inode->i_mapping->private_list,
897 idx, idx + 1);
898
899 } else if (!is_vma_resv_set(vma, HPAGE_RESV_OWNER)) {
900 return 1;
901
902 } else {
903 int err;
904 pgoff_t idx = vma_hugecache_offset(h, vma, addr);
905 struct resv_map *reservations = vma_resv_map(vma);
906
907 err = region_chg(&reservations->regions, idx, idx + 1);
908 if (err < 0)
909 return err;
910 return 0;
911 }
912}
913static void vma_commit_reservation(struct hstate *h,
914 struct vm_area_struct *vma, unsigned long addr)
915{
916 struct address_space *mapping = vma->vm_file->f_mapping;
917 struct inode *inode = mapping->host;
918
919 if (vma->vm_flags & VM_SHARED) {
920 pgoff_t idx = vma_hugecache_offset(h, vma, addr);
921 region_add(&inode->i_mapping->private_list, idx, idx + 1);
922
923 } else if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) {
924 pgoff_t idx = vma_hugecache_offset(h, vma, addr);
925 struct resv_map *reservations = vma_resv_map(vma);
926
927
928 region_add(&reservations->regions, idx, idx + 1);
929 }
930}
931
932static struct page *alloc_huge_page(struct vm_area_struct *vma,
933 unsigned long addr, int avoid_reserve)
934{
935 struct hstate *h = hstate_vma(vma);
936 struct page *page;
937 struct address_space *mapping = vma->vm_file->f_mapping;
938 struct inode *inode = mapping->host;
939 unsigned int chg;
940
941
942
943
944
945
946
947
948 chg = vma_needs_reservation(h, vma, addr);
949 if (chg < 0)
950 return ERR_PTR(chg);
951 if (chg)
952 if (hugetlb_get_quota(inode->i_mapping, chg))
953 return ERR_PTR(-ENOSPC);
954
955 spin_lock(&hugetlb_lock);
956 page = dequeue_huge_page_vma(h, vma, addr, avoid_reserve);
957 spin_unlock(&hugetlb_lock);
958
959 if (!page) {
960 page = alloc_buddy_huge_page(h, vma, addr);
961 if (!page) {
962 hugetlb_put_quota(inode->i_mapping, chg);
963 return ERR_PTR(-VM_FAULT_OOM);
964 }
965 }
966
967 set_page_refcounted(page);
968 set_page_private(page, (unsigned long) mapping);
969
970 vma_commit_reservation(h, vma, addr);
971
972 return page;
973}
974
975__attribute__((weak)) int alloc_bootmem_huge_page(struct hstate *h)
976{
977 struct huge_bootmem_page *m;
978 int nr_nodes = nodes_weight(node_online_map);
979
980 while (nr_nodes) {
981 void *addr;
982
983 addr = __alloc_bootmem_node_nopanic(
984 NODE_DATA(h->hugetlb_next_nid),
985 huge_page_size(h), huge_page_size(h), 0);
986
987 if (addr) {
988
989
990
991
992
993 m = addr;
994 if (m)
995 goto found;
996 }
997 hstate_next_node(h);
998 nr_nodes--;
999 }
1000 return 0;
1001
1002found:
1003 BUG_ON((unsigned long)virt_to_phys(m) & (huge_page_size(h) - 1));
1004
1005 list_add(&m->list, &huge_boot_pages);
1006 m->hstate = h;
1007 return 1;
1008}
1009
1010static void prep_compound_huge_page(struct page *page, int order)
1011{
1012 if (unlikely(order > (MAX_ORDER - 1)))
1013 prep_compound_gigantic_page(page, order);
1014 else
1015 prep_compound_page(page, order);
1016}
1017
1018
1019static void __init gather_bootmem_prealloc(void)
1020{
1021 struct huge_bootmem_page *m;
1022
1023 list_for_each_entry(m, &huge_boot_pages, list) {
1024 struct page *page = virt_to_page(m);
1025 struct hstate *h = m->hstate;
1026 __ClearPageReserved(page);
1027 WARN_ON(page_count(page) != 1);
1028 prep_compound_huge_page(page, h->order);
1029 prep_new_huge_page(h, page, page_to_nid(page));
1030 }
1031}
1032
1033static void __init hugetlb_hstate_alloc_pages(struct hstate *h)
1034{
1035 unsigned long i;
1036
1037 for (i = 0; i < h->max_huge_pages; ++i) {
1038 if (h->order >= MAX_ORDER) {
1039 if (!alloc_bootmem_huge_page(h))
1040 break;
1041 } else if (!alloc_fresh_huge_page(h))
1042 break;
1043 }
1044 h->max_huge_pages = i;
1045}
1046
1047static void __init hugetlb_init_hstates(void)
1048{
1049 struct hstate *h;
1050
1051 for_each_hstate(h) {
1052
1053 if (h->order < MAX_ORDER)
1054 hugetlb_hstate_alloc_pages(h);
1055 }
1056}
1057
1058static char * __init memfmt(char *buf, unsigned long n)
1059{
1060 if (n >= (1UL << 30))
1061 sprintf(buf, "%lu GB", n >> 30);
1062 else if (n >= (1UL << 20))
1063 sprintf(buf, "%lu MB", n >> 20);
1064 else
1065 sprintf(buf, "%lu KB", n >> 10);
1066 return buf;
1067}
1068
1069static void __init report_hugepages(void)
1070{
1071 struct hstate *h;
1072
1073 for_each_hstate(h) {
1074 char buf[32];
1075 printk(KERN_INFO "HugeTLB registered %s page size, "
1076 "pre-allocated %ld pages\n",
1077 memfmt(buf, huge_page_size(h)),
1078 h->free_huge_pages);
1079 }
1080}
1081
1082#ifdef CONFIG_HIGHMEM
1083static void try_to_free_low(struct hstate *h, unsigned long count)
1084{
1085 int i;
1086
1087 if (h->order >= MAX_ORDER)
1088 return;
1089
1090 for (i = 0; i < MAX_NUMNODES; ++i) {
1091 struct page *page, *next;
1092 struct list_head *freel = &h->hugepage_freelists[i];
1093 list_for_each_entry_safe(page, next, freel, lru) {
1094 if (count >= h->nr_huge_pages)
1095 return;
1096 if (PageHighMem(page))
1097 continue;
1098 list_del(&page->lru);
1099 update_and_free_page(h, page);
1100 h->free_huge_pages--;
1101 h->free_huge_pages_node[page_to_nid(page)]--;
1102 }
1103 }
1104}
1105#else
1106static inline void try_to_free_low(struct hstate *h, unsigned long count)
1107{
1108}
1109#endif
1110
1111#define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages)
1112static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count)
1113{
1114 unsigned long min_count, ret;
1115
1116 if (h->order >= MAX_ORDER)
1117 return h->max_huge_pages;
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130 spin_lock(&hugetlb_lock);
1131 while (h->surplus_huge_pages && count > persistent_huge_pages(h)) {
1132 if (!adjust_pool_surplus(h, -1))
1133 break;
1134 }
1135
1136 while (count > persistent_huge_pages(h)) {
1137
1138
1139
1140
1141
1142 spin_unlock(&hugetlb_lock);
1143 ret = alloc_fresh_huge_page(h);
1144 spin_lock(&hugetlb_lock);
1145 if (!ret)
1146 goto out;
1147
1148 }
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165 min_count = h->resv_huge_pages + h->nr_huge_pages - h->free_huge_pages;
1166 min_count = max(count, min_count);
1167 try_to_free_low(h, min_count);
1168 while (min_count < persistent_huge_pages(h)) {
1169 struct page *page = dequeue_huge_page(h);
1170 if (!page)
1171 break;
1172 update_and_free_page(h, page);
1173 }
1174 while (count < persistent_huge_pages(h)) {
1175 if (!adjust_pool_surplus(h, 1))
1176 break;
1177 }
1178out:
1179 ret = persistent_huge_pages(h);
1180 spin_unlock(&hugetlb_lock);
1181 return ret;
1182}
1183
1184#define HSTATE_ATTR_RO(_name) \
1185 static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
1186
1187#define HSTATE_ATTR(_name) \
1188 static struct kobj_attribute _name##_attr = \
1189 __ATTR(_name, 0644, _name##_show, _name##_store)
1190
1191static struct kobject *hugepages_kobj;
1192static struct kobject *hstate_kobjs[HUGE_MAX_HSTATE];
1193
1194static struct hstate *kobj_to_hstate(struct kobject *kobj)
1195{
1196 int i;
1197 for (i = 0; i < HUGE_MAX_HSTATE; i++)
1198 if (hstate_kobjs[i] == kobj)
1199 return &hstates[i];
1200 BUG();
1201 return NULL;
1202}
1203
1204static ssize_t nr_hugepages_show(struct kobject *kobj,
1205 struct kobj_attribute *attr, char *buf)
1206{
1207 struct hstate *h = kobj_to_hstate(kobj);
1208 return sprintf(buf, "%lu\n", h->nr_huge_pages);
1209}
1210static ssize_t nr_hugepages_store(struct kobject *kobj,
1211 struct kobj_attribute *attr, const char *buf, size_t count)
1212{
1213 int err;
1214 unsigned long input;
1215 struct hstate *h = kobj_to_hstate(kobj);
1216
1217 err = strict_strtoul(buf, 10, &input);
1218 if (err)
1219 return 0;
1220
1221 h->max_huge_pages = set_max_huge_pages(h, input);
1222
1223 return count;
1224}
1225HSTATE_ATTR(nr_hugepages);
1226
1227static ssize_t nr_overcommit_hugepages_show(struct kobject *kobj,
1228 struct kobj_attribute *attr, char *buf)
1229{
1230 struct hstate *h = kobj_to_hstate(kobj);
1231 return sprintf(buf, "%lu\n", h->nr_overcommit_huge_pages);
1232}
1233static ssize_t nr_overcommit_hugepages_store(struct kobject *kobj,
1234 struct kobj_attribute *attr, const char *buf, size_t count)
1235{
1236 int err;
1237 unsigned long input;
1238 struct hstate *h = kobj_to_hstate(kobj);
1239
1240 err = strict_strtoul(buf, 10, &input);
1241 if (err)
1242 return 0;
1243
1244 spin_lock(&hugetlb_lock);
1245 h->nr_overcommit_huge_pages = input;
1246 spin_unlock(&hugetlb_lock);
1247
1248 return count;
1249}
1250HSTATE_ATTR(nr_overcommit_hugepages);
1251
1252static ssize_t free_hugepages_show(struct kobject *kobj,
1253 struct kobj_attribute *attr, char *buf)
1254{
1255 struct hstate *h = kobj_to_hstate(kobj);
1256 return sprintf(buf, "%lu\n", h->free_huge_pages);
1257}
1258HSTATE_ATTR_RO(free_hugepages);
1259
1260static ssize_t resv_hugepages_show(struct kobject *kobj,
1261 struct kobj_attribute *attr, char *buf)
1262{
1263 struct hstate *h = kobj_to_hstate(kobj);
1264 return sprintf(buf, "%lu\n", h->resv_huge_pages);
1265}
1266HSTATE_ATTR_RO(resv_hugepages);
1267
1268static ssize_t surplus_hugepages_show(struct kobject *kobj,
1269 struct kobj_attribute *attr, char *buf)
1270{
1271 struct hstate *h = kobj_to_hstate(kobj);
1272 return sprintf(buf, "%lu\n", h->surplus_huge_pages);
1273}
1274HSTATE_ATTR_RO(surplus_hugepages);
1275
1276static struct attribute *hstate_attrs[] = {
1277 &nr_hugepages_attr.attr,
1278 &nr_overcommit_hugepages_attr.attr,
1279 &free_hugepages_attr.attr,
1280 &resv_hugepages_attr.attr,
1281 &surplus_hugepages_attr.attr,
1282 NULL,
1283};
1284
1285static struct attribute_group hstate_attr_group = {
1286 .attrs = hstate_attrs,
1287};
1288
1289static int __init hugetlb_sysfs_add_hstate(struct hstate *h)
1290{
1291 int retval;
1292
1293 hstate_kobjs[h - hstates] = kobject_create_and_add(h->name,
1294 hugepages_kobj);
1295 if (!hstate_kobjs[h - hstates])
1296 return -ENOMEM;
1297
1298 retval = sysfs_create_group(hstate_kobjs[h - hstates],
1299 &hstate_attr_group);
1300 if (retval)
1301 kobject_put(hstate_kobjs[h - hstates]);
1302
1303 return retval;
1304}
1305
1306static void __init hugetlb_sysfs_init(void)
1307{
1308 struct hstate *h;
1309 int err;
1310
1311 hugepages_kobj = kobject_create_and_add("hugepages", mm_kobj);
1312 if (!hugepages_kobj)
1313 return;
1314
1315 for_each_hstate(h) {
1316 err = hugetlb_sysfs_add_hstate(h);
1317 if (err)
1318 printk(KERN_ERR "Hugetlb: Unable to add hstate %s",
1319 h->name);
1320 }
1321}
1322
1323static void __exit hugetlb_exit(void)
1324{
1325 struct hstate *h;
1326
1327 for_each_hstate(h) {
1328 kobject_put(hstate_kobjs[h - hstates]);
1329 }
1330
1331 kobject_put(hugepages_kobj);
1332}
1333module_exit(hugetlb_exit);
1334
1335static int __init hugetlb_init(void)
1336{
1337
1338
1339
1340
1341 if (HPAGE_SHIFT == 0)
1342 return 0;
1343
1344 if (!size_to_hstate(default_hstate_size)) {
1345 default_hstate_size = HPAGE_SIZE;
1346 if (!size_to_hstate(default_hstate_size))
1347 hugetlb_add_hstate(HUGETLB_PAGE_ORDER);
1348 }
1349 default_hstate_idx = size_to_hstate(default_hstate_size) - hstates;
1350 if (default_hstate_max_huge_pages)
1351 default_hstate.max_huge_pages = default_hstate_max_huge_pages;
1352
1353 hugetlb_init_hstates();
1354
1355 gather_bootmem_prealloc();
1356
1357 report_hugepages();
1358
1359 hugetlb_sysfs_init();
1360
1361 return 0;
1362}
1363module_init(hugetlb_init);
1364
1365
1366void __init hugetlb_add_hstate(unsigned order)
1367{
1368 struct hstate *h;
1369 unsigned long i;
1370
1371 if (size_to_hstate(PAGE_SIZE << order)) {
1372 printk(KERN_WARNING "hugepagesz= specified twice, ignoring\n");
1373 return;
1374 }
1375 BUG_ON(max_hstate >= HUGE_MAX_HSTATE);
1376 BUG_ON(order == 0);
1377 h = &hstates[max_hstate++];
1378 h->order = order;
1379 h->mask = ~((1ULL << (order + PAGE_SHIFT)) - 1);
1380 h->nr_huge_pages = 0;
1381 h->free_huge_pages = 0;
1382 for (i = 0; i < MAX_NUMNODES; ++i)
1383 INIT_LIST_HEAD(&h->hugepage_freelists[i]);
1384 h->hugetlb_next_nid = first_node(node_online_map);
1385 snprintf(h->name, HSTATE_NAME_LEN, "hugepages-%lukB",
1386 huge_page_size(h)/1024);
1387
1388 parsed_hstate = h;
1389}
1390
1391static int __init hugetlb_nrpages_setup(char *s)
1392{
1393 unsigned long *mhp;
1394 static unsigned long *last_mhp;
1395
1396
1397
1398
1399
1400 if (!max_hstate)
1401 mhp = &default_hstate_max_huge_pages;
1402 else
1403 mhp = &parsed_hstate->max_huge_pages;
1404
1405 if (mhp == last_mhp) {
1406 printk(KERN_WARNING "hugepages= specified twice without "
1407 "interleaving hugepagesz=, ignoring\n");
1408 return 1;
1409 }
1410
1411 if (sscanf(s, "%lu", mhp) <= 0)
1412 *mhp = 0;
1413
1414
1415
1416
1417
1418
1419 if (max_hstate && parsed_hstate->order >= MAX_ORDER)
1420 hugetlb_hstate_alloc_pages(parsed_hstate);
1421
1422 last_mhp = mhp;
1423
1424 return 1;
1425}
1426__setup("hugepages=", hugetlb_nrpages_setup);
1427
1428static int __init hugetlb_default_setup(char *s)
1429{
1430 default_hstate_size = memparse(s, &s);
1431 return 1;
1432}
1433__setup("default_hugepagesz=", hugetlb_default_setup);
1434
1435static unsigned int cpuset_mems_nr(unsigned int *array)
1436{
1437 int node;
1438 unsigned int nr = 0;
1439
1440 for_each_node_mask(node, cpuset_current_mems_allowed)
1441 nr += array[node];
1442
1443 return nr;
1444}
1445
1446#ifdef CONFIG_SYSCTL
1447int hugetlb_sysctl_handler(struct ctl_table *table, int write,
1448 struct file *file, void __user *buffer,
1449 size_t *length, loff_t *ppos)
1450{
1451 struct hstate *h = &default_hstate;
1452 unsigned long tmp;
1453
1454 if (!write)
1455 tmp = h->max_huge_pages;
1456
1457 table->data = &tmp;
1458 table->maxlen = sizeof(unsigned long);
1459 proc_doulongvec_minmax(table, write, file, buffer, length, ppos);
1460
1461 if (write)
1462 h->max_huge_pages = set_max_huge_pages(h, tmp);
1463
1464 return 0;
1465}
1466
1467int hugetlb_treat_movable_handler(struct ctl_table *table, int write,
1468 struct file *file, void __user *buffer,
1469 size_t *length, loff_t *ppos)
1470{
1471 proc_dointvec(table, write, file, buffer, length, ppos);
1472 if (hugepages_treat_as_movable)
1473 htlb_alloc_mask = GFP_HIGHUSER_MOVABLE;
1474 else
1475 htlb_alloc_mask = GFP_HIGHUSER;
1476 return 0;
1477}
1478
1479int hugetlb_overcommit_handler(struct ctl_table *table, int write,
1480 struct file *file, void __user *buffer,
1481 size_t *length, loff_t *ppos)
1482{
1483 struct hstate *h = &default_hstate;
1484 unsigned long tmp;
1485
1486 if (!write)
1487 tmp = h->nr_overcommit_huge_pages;
1488
1489 table->data = &tmp;
1490 table->maxlen = sizeof(unsigned long);
1491 proc_doulongvec_minmax(table, write, file, buffer, length, ppos);
1492
1493 if (write) {
1494 spin_lock(&hugetlb_lock);
1495 h->nr_overcommit_huge_pages = tmp;
1496 spin_unlock(&hugetlb_lock);
1497 }
1498
1499 return 0;
1500}
1501
1502#endif
1503
1504void hugetlb_report_meminfo(struct seq_file *m)
1505{
1506 struct hstate *h = &default_hstate;
1507 seq_printf(m,
1508 "HugePages_Total: %5lu\n"
1509 "HugePages_Free: %5lu\n"
1510 "HugePages_Rsvd: %5lu\n"
1511 "HugePages_Surp: %5lu\n"
1512 "Hugepagesize: %8lu kB\n",
1513 h->nr_huge_pages,
1514 h->free_huge_pages,
1515 h->resv_huge_pages,
1516 h->surplus_huge_pages,
1517 1UL << (huge_page_order(h) + PAGE_SHIFT - 10));
1518}
1519
1520int hugetlb_report_node_meminfo(int nid, char *buf)
1521{
1522 struct hstate *h = &default_hstate;
1523 return sprintf(buf,
1524 "Node %d HugePages_Total: %5u\n"
1525 "Node %d HugePages_Free: %5u\n"
1526 "Node %d HugePages_Surp: %5u\n",
1527 nid, h->nr_huge_pages_node[nid],
1528 nid, h->free_huge_pages_node[nid],
1529 nid, h->surplus_huge_pages_node[nid]);
1530}
1531
1532
1533unsigned long hugetlb_total_pages(void)
1534{
1535 struct hstate *h = &default_hstate;
1536 return h->nr_huge_pages * pages_per_huge_page(h);
1537}
1538
1539static int hugetlb_acct_memory(struct hstate *h, long delta)
1540{
1541 int ret = -ENOMEM;
1542
1543 spin_lock(&hugetlb_lock);
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561 if (delta > 0) {
1562 if (gather_surplus_pages(h, delta) < 0)
1563 goto out;
1564
1565 if (delta > cpuset_mems_nr(h->free_huge_pages_node)) {
1566 return_unused_surplus_pages(h, delta);
1567 goto out;
1568 }
1569 }
1570
1571 ret = 0;
1572 if (delta < 0)
1573 return_unused_surplus_pages(h, (unsigned long) -delta);
1574
1575out:
1576 spin_unlock(&hugetlb_lock);
1577 return ret;
1578}
1579
1580static void hugetlb_vm_op_open(struct vm_area_struct *vma)
1581{
1582 struct resv_map *reservations = vma_resv_map(vma);
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592 if (reservations)
1593 kref_get(&reservations->refs);
1594}
1595
1596static void hugetlb_vm_op_close(struct vm_area_struct *vma)
1597{
1598 struct hstate *h = hstate_vma(vma);
1599 struct resv_map *reservations = vma_resv_map(vma);
1600 unsigned long reserve;
1601 unsigned long start;
1602 unsigned long end;
1603
1604 if (reservations) {
1605 start = vma_hugecache_offset(h, vma, vma->vm_start);
1606 end = vma_hugecache_offset(h, vma, vma->vm_end);
1607
1608 reserve = (end - start) -
1609 region_count(&reservations->regions, start, end);
1610
1611 kref_put(&reservations->refs, resv_map_release);
1612
1613 if (reserve) {
1614 hugetlb_acct_memory(h, -reserve);
1615 hugetlb_put_quota(vma->vm_file->f_mapping, reserve);
1616 }
1617 }
1618}
1619
1620
1621
1622
1623
1624
1625
1626static int hugetlb_vm_op_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1627{
1628 BUG();
1629 return 0;
1630}
1631
1632struct vm_operations_struct hugetlb_vm_ops = {
1633 .fault = hugetlb_vm_op_fault,
1634 .open = hugetlb_vm_op_open,
1635 .close = hugetlb_vm_op_close,
1636};
1637
1638static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page,
1639 int writable)
1640{
1641 pte_t entry;
1642
1643 if (writable) {
1644 entry =
1645 pte_mkwrite(pte_mkdirty(mk_pte(page, vma->vm_page_prot)));
1646 } else {
1647 entry = huge_pte_wrprotect(mk_pte(page, vma->vm_page_prot));
1648 }
1649 entry = pte_mkyoung(entry);
1650 entry = pte_mkhuge(entry);
1651
1652 return entry;
1653}
1654
1655static void set_huge_ptep_writable(struct vm_area_struct *vma,
1656 unsigned long address, pte_t *ptep)
1657{
1658 pte_t entry;
1659
1660 entry = pte_mkwrite(pte_mkdirty(huge_ptep_get(ptep)));
1661 if (huge_ptep_set_access_flags(vma, address, ptep, entry, 1)) {
1662 update_mmu_cache(vma, address, entry);
1663 }
1664}
1665
1666
1667int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
1668 struct vm_area_struct *vma)
1669{
1670 pte_t *src_pte, *dst_pte, entry;
1671 struct page *ptepage;
1672 unsigned long addr;
1673 int cow;
1674 struct hstate *h = hstate_vma(vma);
1675 unsigned long sz = huge_page_size(h);
1676
1677 cow = (vma->vm_flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE;
1678
1679 for (addr = vma->vm_start; addr < vma->vm_end; addr += sz) {
1680 src_pte = huge_pte_offset(src, addr);
1681 if (!src_pte)
1682 continue;
1683 dst_pte = huge_pte_alloc(dst, addr, sz);
1684 if (!dst_pte)
1685 goto nomem;
1686
1687
1688 if (dst_pte == src_pte)
1689 continue;
1690
1691 spin_lock(&dst->page_table_lock);
1692 spin_lock_nested(&src->page_table_lock, SINGLE_DEPTH_NESTING);
1693 if (!huge_pte_none(huge_ptep_get(src_pte))) {
1694 if (cow)
1695 huge_ptep_set_wrprotect(src, addr, src_pte);
1696 entry = huge_ptep_get(src_pte);
1697 ptepage = pte_page(entry);
1698 get_page(ptepage);
1699 set_huge_pte_at(dst, addr, dst_pte, entry);
1700 }
1701 spin_unlock(&src->page_table_lock);
1702 spin_unlock(&dst->page_table_lock);
1703 }
1704 return 0;
1705
1706nomem:
1707 return -ENOMEM;
1708}
1709
1710void __unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
1711 unsigned long end, struct page *ref_page)
1712{
1713 struct mm_struct *mm = vma->vm_mm;
1714 unsigned long address;
1715 pte_t *ptep;
1716 pte_t pte;
1717 struct page *page;
1718 struct page *tmp;
1719 struct hstate *h = hstate_vma(vma);
1720 unsigned long sz = huge_page_size(h);
1721
1722
1723
1724
1725
1726
1727 LIST_HEAD(page_list);
1728
1729 WARN_ON(!is_vm_hugetlb_page(vma));
1730 BUG_ON(start & ~huge_page_mask(h));
1731 BUG_ON(end & ~huge_page_mask(h));
1732
1733 mmu_notifier_invalidate_range_start(mm, start, end);
1734 spin_lock(&mm->page_table_lock);
1735 for (address = start; address < end; address += sz) {
1736 ptep = huge_pte_offset(mm, address);
1737 if (!ptep)
1738 continue;
1739
1740 if (huge_pmd_unshare(mm, &address, ptep))
1741 continue;
1742
1743
1744
1745
1746
1747
1748 if (ref_page) {
1749 pte = huge_ptep_get(ptep);
1750 if (huge_pte_none(pte))
1751 continue;
1752 page = pte_page(pte);
1753 if (page != ref_page)
1754 continue;
1755
1756
1757
1758
1759
1760
1761 set_vma_resv_flags(vma, HPAGE_RESV_UNMAPPED);
1762 }
1763
1764 pte = huge_ptep_get_and_clear(mm, address, ptep);
1765 if (huge_pte_none(pte))
1766 continue;
1767
1768 page = pte_page(pte);
1769 if (pte_dirty(pte))
1770 set_page_dirty(page);
1771 list_add(&page->lru, &page_list);
1772 }
1773 spin_unlock(&mm->page_table_lock);
1774 flush_tlb_range(vma, start, end);
1775 mmu_notifier_invalidate_range_end(mm, start, end);
1776 list_for_each_entry_safe(page, tmp, &page_list, lru) {
1777 list_del(&page->lru);
1778 put_page(page);
1779 }
1780}
1781
1782void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
1783 unsigned long end, struct page *ref_page)
1784{
1785 spin_lock(&vma->vm_file->f_mapping->i_mmap_lock);
1786 __unmap_hugepage_range(vma, start, end, ref_page);
1787 spin_unlock(&vma->vm_file->f_mapping->i_mmap_lock);
1788}
1789
1790
1791
1792
1793
1794
1795
1796static int unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma,
1797 struct page *page, unsigned long address)
1798{
1799 struct hstate *h = hstate_vma(vma);
1800 struct vm_area_struct *iter_vma;
1801 struct address_space *mapping;
1802 struct prio_tree_iter iter;
1803 pgoff_t pgoff;
1804
1805
1806
1807
1808
1809 address = address & huge_page_mask(h);
1810 pgoff = ((address - vma->vm_start) >> PAGE_SHIFT)
1811 + (vma->vm_pgoff >> PAGE_SHIFT);
1812 mapping = (struct address_space *)page_private(page);
1813
1814 vma_prio_tree_foreach(iter_vma, &iter, &mapping->i_mmap, pgoff, pgoff) {
1815
1816 if (iter_vma == vma)
1817 continue;
1818
1819
1820
1821
1822
1823
1824
1825
1826 if (!is_vma_resv_set(iter_vma, HPAGE_RESV_OWNER))
1827 unmap_hugepage_range(iter_vma,
1828 address, address + huge_page_size(h),
1829 page);
1830 }
1831
1832 return 1;
1833}
1834
1835static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma,
1836 unsigned long address, pte_t *ptep, pte_t pte,
1837 struct page *pagecache_page)
1838{
1839 struct hstate *h = hstate_vma(vma);
1840 struct page *old_page, *new_page;
1841 int avoidcopy;
1842 int outside_reserve = 0;
1843
1844 old_page = pte_page(pte);
1845
1846retry_avoidcopy:
1847
1848
1849 avoidcopy = (page_count(old_page) == 1);
1850 if (avoidcopy) {
1851 set_huge_ptep_writable(vma, address, ptep);
1852 return 0;
1853 }
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864 if (!(vma->vm_flags & VM_SHARED) &&
1865 is_vma_resv_set(vma, HPAGE_RESV_OWNER) &&
1866 old_page != pagecache_page)
1867 outside_reserve = 1;
1868
1869 page_cache_get(old_page);
1870 new_page = alloc_huge_page(vma, address, outside_reserve);
1871
1872 if (IS_ERR(new_page)) {
1873 page_cache_release(old_page);
1874
1875
1876
1877
1878
1879
1880
1881
1882 if (outside_reserve) {
1883 BUG_ON(huge_pte_none(pte));
1884 if (unmap_ref_private(mm, vma, old_page, address)) {
1885 BUG_ON(page_count(old_page) != 1);
1886 BUG_ON(huge_pte_none(pte));
1887 goto retry_avoidcopy;
1888 }
1889 WARN_ON_ONCE(1);
1890 }
1891
1892 return -PTR_ERR(new_page);
1893 }
1894
1895 spin_unlock(&mm->page_table_lock);
1896 copy_huge_page(new_page, old_page, address, vma);
1897 __SetPageUptodate(new_page);
1898 spin_lock(&mm->page_table_lock);
1899
1900 ptep = huge_pte_offset(mm, address & huge_page_mask(h));
1901 if (likely(pte_same(huge_ptep_get(ptep), pte))) {
1902
1903 huge_ptep_clear_flush(vma, address, ptep);
1904 set_huge_pte_at(mm, address, ptep,
1905 make_huge_pte(vma, new_page, 1));
1906
1907 new_page = old_page;
1908 }
1909 page_cache_release(new_page);
1910 page_cache_release(old_page);
1911 return 0;
1912}
1913
1914
1915static struct page *hugetlbfs_pagecache_page(struct hstate *h,
1916 struct vm_area_struct *vma, unsigned long address)
1917{
1918 struct address_space *mapping;
1919 pgoff_t idx;
1920
1921 mapping = vma->vm_file->f_mapping;
1922 idx = vma_hugecache_offset(h, vma, address);
1923
1924 return find_lock_page(mapping, idx);
1925}
1926
1927static int hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma,
1928 unsigned long address, pte_t *ptep, int write_access)
1929{
1930 struct hstate *h = hstate_vma(vma);
1931 int ret = VM_FAULT_SIGBUS;
1932 pgoff_t idx;
1933 unsigned long size;
1934 struct page *page;
1935 struct address_space *mapping;
1936 pte_t new_pte;
1937
1938
1939
1940
1941
1942
1943 if (is_vma_resv_set(vma, HPAGE_RESV_UNMAPPED)) {
1944 printk(KERN_WARNING
1945 "PID %d killed due to inadequate hugepage pool\n",
1946 current->pid);
1947 return ret;
1948 }
1949
1950 mapping = vma->vm_file->f_mapping;
1951 idx = vma_hugecache_offset(h, vma, address);
1952
1953
1954
1955
1956
1957retry:
1958 page = find_lock_page(mapping, idx);
1959 if (!page) {
1960 size = i_size_read(mapping->host) >> huge_page_shift(h);
1961 if (idx >= size)
1962 goto out;
1963 page = alloc_huge_page(vma, address, 0);
1964 if (IS_ERR(page)) {
1965 ret = -PTR_ERR(page);
1966 goto out;
1967 }
1968 clear_huge_page(page, address, huge_page_size(h));
1969 __SetPageUptodate(page);
1970
1971 if (vma->vm_flags & VM_SHARED) {
1972 int err;
1973 struct inode *inode = mapping->host;
1974
1975 err = add_to_page_cache(page, mapping, idx, GFP_KERNEL);
1976 if (err) {
1977 put_page(page);
1978 if (err == -EEXIST)
1979 goto retry;
1980 goto out;
1981 }
1982
1983 spin_lock(&inode->i_lock);
1984 inode->i_blocks += blocks_per_huge_page(h);
1985 spin_unlock(&inode->i_lock);
1986 } else
1987 lock_page(page);
1988 }
1989
1990
1991
1992
1993
1994
1995
1996 if (write_access && !(vma->vm_flags & VM_SHARED))
1997 if (vma_needs_reservation(h, vma, address) < 0) {
1998 ret = VM_FAULT_OOM;
1999 goto backout_unlocked;
2000 }
2001
2002 spin_lock(&mm->page_table_lock);
2003 size = i_size_read(mapping->host) >> huge_page_shift(h);
2004 if (idx >= size)
2005 goto backout;
2006
2007 ret = 0;
2008 if (!huge_pte_none(huge_ptep_get(ptep)))
2009 goto backout;
2010
2011 new_pte = make_huge_pte(vma, page, ((vma->vm_flags & VM_WRITE)
2012 && (vma->vm_flags & VM_SHARED)));
2013 set_huge_pte_at(mm, address, ptep, new_pte);
2014
2015 if (write_access && !(vma->vm_flags & VM_SHARED)) {
2016
2017 ret = hugetlb_cow(mm, vma, address, ptep, new_pte, page);
2018 }
2019
2020 spin_unlock(&mm->page_table_lock);
2021 unlock_page(page);
2022out:
2023 return ret;
2024
2025backout:
2026 spin_unlock(&mm->page_table_lock);
2027backout_unlocked:
2028 unlock_page(page);
2029 put_page(page);
2030 goto out;
2031}
2032
2033int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
2034 unsigned long address, int write_access)
2035{
2036 pte_t *ptep;
2037 pte_t entry;
2038 int ret;
2039 struct page *pagecache_page = NULL;
2040 static DEFINE_MUTEX(hugetlb_instantiation_mutex);
2041 struct hstate *h = hstate_vma(vma);
2042
2043 ptep = huge_pte_alloc(mm, address, huge_page_size(h));
2044 if (!ptep)
2045 return VM_FAULT_OOM;
2046
2047
2048
2049
2050
2051
2052 mutex_lock(&hugetlb_instantiation_mutex);
2053 entry = huge_ptep_get(ptep);
2054 if (huge_pte_none(entry)) {
2055 ret = hugetlb_no_page(mm, vma, address, ptep, write_access);
2056 goto out_mutex;
2057 }
2058
2059 ret = 0;
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069 if (write_access && !pte_write(entry)) {
2070 if (vma_needs_reservation(h, vma, address) < 0) {
2071 ret = VM_FAULT_OOM;
2072 goto out_mutex;
2073 }
2074
2075 if (!(vma->vm_flags & VM_SHARED))
2076 pagecache_page = hugetlbfs_pagecache_page(h,
2077 vma, address);
2078 }
2079
2080 spin_lock(&mm->page_table_lock);
2081
2082 if (unlikely(!pte_same(entry, huge_ptep_get(ptep))))
2083 goto out_page_table_lock;
2084
2085
2086 if (write_access) {
2087 if (!pte_write(entry)) {
2088 ret = hugetlb_cow(mm, vma, address, ptep, entry,
2089 pagecache_page);
2090 goto out_page_table_lock;
2091 }
2092 entry = pte_mkdirty(entry);
2093 }
2094 entry = pte_mkyoung(entry);
2095 if (huge_ptep_set_access_flags(vma, address, ptep, entry, write_access))
2096 update_mmu_cache(vma, address, entry);
2097
2098out_page_table_lock:
2099 spin_unlock(&mm->page_table_lock);
2100
2101 if (pagecache_page) {
2102 unlock_page(pagecache_page);
2103 put_page(pagecache_page);
2104 }
2105
2106out_mutex:
2107 mutex_unlock(&hugetlb_instantiation_mutex);
2108
2109 return ret;
2110}
2111
2112
2113__attribute__((weak)) struct page *
2114follow_huge_pud(struct mm_struct *mm, unsigned long address,
2115 pud_t *pud, int write)
2116{
2117 BUG();
2118 return NULL;
2119}
2120
2121static int huge_zeropage_ok(pte_t *ptep, int write, int shared)
2122{
2123 if (!ptep || write || shared)
2124 return 0;
2125 else
2126 return huge_pte_none(huge_ptep_get(ptep));
2127}
2128
2129int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
2130 struct page **pages, struct vm_area_struct **vmas,
2131 unsigned long *position, int *length, int i,
2132 int write)
2133{
2134 unsigned long pfn_offset;
2135 unsigned long vaddr = *position;
2136 int remainder = *length;
2137 struct hstate *h = hstate_vma(vma);
2138 int zeropage_ok = 0;
2139 int shared = vma->vm_flags & VM_SHARED;
2140
2141 spin_lock(&mm->page_table_lock);
2142 while (vaddr < vma->vm_end && remainder) {
2143 pte_t *pte;
2144 struct page *page;
2145
2146
2147
2148
2149
2150
2151 pte = huge_pte_offset(mm, vaddr & huge_page_mask(h));
2152 if (huge_zeropage_ok(pte, write, shared))
2153 zeropage_ok = 1;
2154
2155 if (!pte ||
2156 (huge_pte_none(huge_ptep_get(pte)) && !zeropage_ok) ||
2157 (write && !pte_write(huge_ptep_get(pte)))) {
2158 int ret;
2159
2160 spin_unlock(&mm->page_table_lock);
2161 ret = hugetlb_fault(mm, vma, vaddr, write);
2162 spin_lock(&mm->page_table_lock);
2163 if (!(ret & VM_FAULT_ERROR))
2164 continue;
2165
2166 remainder = 0;
2167 if (!i)
2168 i = -EFAULT;
2169 break;
2170 }
2171
2172 pfn_offset = (vaddr & ~huge_page_mask(h)) >> PAGE_SHIFT;
2173 page = pte_page(huge_ptep_get(pte));
2174same_page:
2175 if (pages) {
2176 if (zeropage_ok)
2177 pages[i] = ZERO_PAGE(0);
2178 else
2179 pages[i] = mem_map_offset(page, pfn_offset);
2180 get_page(pages[i]);
2181 }
2182
2183 if (vmas)
2184 vmas[i] = vma;
2185
2186 vaddr += PAGE_SIZE;
2187 ++pfn_offset;
2188 --remainder;
2189 ++i;
2190 if (vaddr < vma->vm_end && remainder &&
2191 pfn_offset < pages_per_huge_page(h)) {
2192
2193
2194
2195
2196 goto same_page;
2197 }
2198 }
2199 spin_unlock(&mm->page_table_lock);
2200 *length = remainder;
2201 *position = vaddr;
2202
2203 return i;
2204}
2205
2206void hugetlb_change_protection(struct vm_area_struct *vma,
2207 unsigned long address, unsigned long end, pgprot_t newprot)
2208{
2209 struct mm_struct *mm = vma->vm_mm;
2210 unsigned long start = address;
2211 pte_t *ptep;
2212 pte_t pte;
2213 struct hstate *h = hstate_vma(vma);
2214
2215 BUG_ON(address >= end);
2216 flush_cache_range(vma, address, end);
2217
2218 spin_lock(&vma->vm_file->f_mapping->i_mmap_lock);
2219 spin_lock(&mm->page_table_lock);
2220 for (; address < end; address += huge_page_size(h)) {
2221 ptep = huge_pte_offset(mm, address);
2222 if (!ptep)
2223 continue;
2224 if (huge_pmd_unshare(mm, &address, ptep))
2225 continue;
2226 if (!huge_pte_none(huge_ptep_get(ptep))) {
2227 pte = huge_ptep_get_and_clear(mm, address, ptep);
2228 pte = pte_mkhuge(pte_modify(pte, newprot));
2229 set_huge_pte_at(mm, address, ptep, pte);
2230 }
2231 }
2232 spin_unlock(&mm->page_table_lock);
2233 spin_unlock(&vma->vm_file->f_mapping->i_mmap_lock);
2234
2235 flush_tlb_range(vma, start, end);
2236}
2237
2238int hugetlb_reserve_pages(struct inode *inode,
2239 long from, long to,
2240 struct vm_area_struct *vma)
2241{
2242 long ret, chg;
2243 struct hstate *h = hstate_inode(inode);
2244
2245 if (vma && vma->vm_flags & VM_NORESERVE)
2246 return 0;
2247
2248
2249
2250
2251
2252
2253
2254 if (!vma || vma->vm_flags & VM_SHARED)
2255 chg = region_chg(&inode->i_mapping->private_list, from, to);
2256 else {
2257 struct resv_map *resv_map = resv_map_alloc();
2258 if (!resv_map)
2259 return -ENOMEM;
2260
2261 chg = to - from;
2262
2263 set_vma_resv_map(vma, resv_map);
2264 set_vma_resv_flags(vma, HPAGE_RESV_OWNER);
2265 }
2266
2267 if (chg < 0)
2268 return chg;
2269
2270 if (hugetlb_get_quota(inode->i_mapping, chg))
2271 return -ENOSPC;
2272 ret = hugetlb_acct_memory(h, chg);
2273 if (ret < 0) {
2274 hugetlb_put_quota(inode->i_mapping, chg);
2275 return ret;
2276 }
2277 if (!vma || vma->vm_flags & VM_SHARED)
2278 region_add(&inode->i_mapping->private_list, from, to);
2279 return 0;
2280}
2281
2282void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed)
2283{
2284 struct hstate *h = hstate_inode(inode);
2285 long chg = region_truncate(&inode->i_mapping->private_list, offset);
2286
2287 spin_lock(&inode->i_lock);
2288 inode->i_blocks -= blocks_per_huge_page(h);
2289 spin_unlock(&inode->i_lock);
2290
2291 hugetlb_put_quota(inode->i_mapping, (chg - freed));
2292 hugetlb_acct_memory(h, -(chg - freed));
2293}