aboutsummaryrefslogtreecommitdiffstats
path: root/kernel/power/snapshot.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/power/snapshot.c')
-rw-r--r--kernel/power/snapshot.c851
1 files changed, 637 insertions, 214 deletions
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 99f9b7d177d6..fd8251d40eb8 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -1,15 +1,15 @@
1/* 1/*
2 * linux/kernel/power/snapshot.c 2 * linux/kernel/power/snapshot.c
3 * 3 *
4 * This file provide system snapshot/restore functionality. 4 * This file provides system snapshot/restore functionality for swsusp.
5 * 5 *
6 * Copyright (C) 1998-2005 Pavel Machek <pavel@suse.cz> 6 * Copyright (C) 1998-2005 Pavel Machek <pavel@suse.cz>
7 * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl>
7 * 8 *
8 * This file is released under the GPLv2, and is based on swsusp.c. 9 * This file is released under the GPLv2.
9 * 10 *
10 */ 11 */
11 12
12
13#include <linux/version.h> 13#include <linux/version.h>
14#include <linux/module.h> 14#include <linux/module.h>
15#include <linux/mm.h> 15#include <linux/mm.h>
@@ -34,137 +34,24 @@
34 34
35#include "power.h" 35#include "power.h"
36 36
37/* List of PBEs used for creating and restoring the suspend image */ 37/* List of PBEs needed for restoring the pages that were allocated before
38 * the suspend and included in the suspend image, but have also been
39 * allocated by the "resume" kernel, so their contents cannot be written
40 * directly to their "original" page frames.
41 */
38struct pbe *restore_pblist; 42struct pbe *restore_pblist;
39 43
40static unsigned int nr_copy_pages; 44/* Pointer to an auxiliary buffer (1 page) */
41static unsigned int nr_meta_pages;
42static void *buffer; 45static void *buffer;
43 46
44#ifdef CONFIG_HIGHMEM
45unsigned int count_highmem_pages(void)
46{
47 struct zone *zone;
48 unsigned long zone_pfn;
49 unsigned int n = 0;
50
51 for_each_zone (zone)
52 if (is_highmem(zone)) {
53 mark_free_pages(zone);
54 for (zone_pfn = 0; zone_pfn < zone->spanned_pages; zone_pfn++) {
55 struct page *page;
56 unsigned long pfn = zone_pfn + zone->zone_start_pfn;
57 if (!pfn_valid(pfn))
58 continue;
59 page = pfn_to_page(pfn);
60 if (PageReserved(page))
61 continue;
62 if (PageNosaveFree(page))
63 continue;
64 n++;
65 }
66 }
67 return n;
68}
69
70struct highmem_page {
71 char *data;
72 struct page *page;
73 struct highmem_page *next;
74};
75
76static struct highmem_page *highmem_copy;
77
78static int save_highmem_zone(struct zone *zone)
79{
80 unsigned long zone_pfn;
81 mark_free_pages(zone);
82 for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) {
83 struct page *page;
84 struct highmem_page *save;
85 void *kaddr;
86 unsigned long pfn = zone_pfn + zone->zone_start_pfn;
87
88 if (!(pfn%10000))
89 printk(".");
90 if (!pfn_valid(pfn))
91 continue;
92 page = pfn_to_page(pfn);
93 /*
94 * This condition results from rvmalloc() sans vmalloc_32()
95 * and architectural memory reservations. This should be
96 * corrected eventually when the cases giving rise to this
97 * are better understood.
98 */
99 if (PageReserved(page))
100 continue;
101 BUG_ON(PageNosave(page));
102 if (PageNosaveFree(page))
103 continue;
104 save = kmalloc(sizeof(struct highmem_page), GFP_ATOMIC);
105 if (!save)
106 return -ENOMEM;
107 save->next = highmem_copy;
108 save->page = page;
109 save->data = (void *) get_zeroed_page(GFP_ATOMIC);
110 if (!save->data) {
111 kfree(save);
112 return -ENOMEM;
113 }
114 kaddr = kmap_atomic(page, KM_USER0);
115 memcpy(save->data, kaddr, PAGE_SIZE);
116 kunmap_atomic(kaddr, KM_USER0);
117 highmem_copy = save;
118 }
119 return 0;
120}
121
122int save_highmem(void)
123{
124 struct zone *zone;
125 int res = 0;
126
127 pr_debug("swsusp: Saving Highmem");
128 drain_local_pages();
129 for_each_zone (zone) {
130 if (is_highmem(zone))
131 res = save_highmem_zone(zone);
132 if (res)
133 return res;
134 }
135 printk("\n");
136 return 0;
137}
138
139int restore_highmem(void)
140{
141 printk("swsusp: Restoring Highmem\n");
142 while (highmem_copy) {
143 struct highmem_page *save = highmem_copy;
144 void *kaddr;
145 highmem_copy = save->next;
146
147 kaddr = kmap_atomic(save->page, KM_USER0);
148 memcpy(kaddr, save->data, PAGE_SIZE);
149 kunmap_atomic(kaddr, KM_USER0);
150 free_page((long) save->data);
151 kfree(save);
152 }
153 return 0;
154}
155#else
156static inline unsigned int count_highmem_pages(void) {return 0;}
157static inline int save_highmem(void) {return 0;}
158static inline int restore_highmem(void) {return 0;}
159#endif
160
161/** 47/**
162 * @safe_needed - on resume, for storing the PBE list and the image, 48 * @safe_needed - on resume, for storing the PBE list and the image,
163 * we can only use memory pages that do not conflict with the pages 49 * we can only use memory pages that do not conflict with the pages
164 * used before suspend. 50 * used before suspend. The unsafe pages have PageNosaveFree set
51 * and we count them using unsafe_pages.
165 * 52 *
166 * The unsafe pages are marked with the PG_nosave_free flag 53 * Each allocated image page is marked as PageNosave and PageNosaveFree
167 * and we count them using unsafe_pages 54 * so that swsusp_free() can release it.
168 */ 55 */
169 56
170#define PG_ANY 0 57#define PG_ANY 0
@@ -174,7 +61,7 @@ static inline int restore_highmem(void) {return 0;}
174 61
175static unsigned int allocated_unsafe_pages; 62static unsigned int allocated_unsafe_pages;
176 63
177static void *alloc_image_page(gfp_t gfp_mask, int safe_needed) 64static void *get_image_page(gfp_t gfp_mask, int safe_needed)
178{ 65{
179 void *res; 66 void *res;
180 67
@@ -195,20 +82,38 @@ static void *alloc_image_page(gfp_t gfp_mask, int safe_needed)
195 82
196unsigned long get_safe_page(gfp_t gfp_mask) 83unsigned long get_safe_page(gfp_t gfp_mask)
197{ 84{
198 return (unsigned long)alloc_image_page(gfp_mask, PG_SAFE); 85 return (unsigned long)get_image_page(gfp_mask, PG_SAFE);
86}
87
88static struct page *alloc_image_page(gfp_t gfp_mask) {
89 struct page *page;
90
91 page = alloc_page(gfp_mask);
92 if (page) {
93 SetPageNosave(page);
94 SetPageNosaveFree(page);
95 }
96 return page;
199} 97}
200 98
201/** 99/**
202 * free_image_page - free page represented by @addr, allocated with 100 * free_image_page - free page represented by @addr, allocated with
203 * alloc_image_page (page flags set by it must be cleared) 101 * get_image_page (page flags set by it must be cleared)
204 */ 102 */
205 103
206static inline void free_image_page(void *addr, int clear_nosave_free) 104static inline void free_image_page(void *addr, int clear_nosave_free)
207{ 105{
208 ClearPageNosave(virt_to_page(addr)); 106 struct page *page;
107
108 BUG_ON(!virt_addr_valid(addr));
109
110 page = virt_to_page(addr);
111
112 ClearPageNosave(page);
209 if (clear_nosave_free) 113 if (clear_nosave_free)
210 ClearPageNosaveFree(virt_to_page(addr)); 114 ClearPageNosaveFree(page);
211 free_page((unsigned long)addr); 115
116 __free_page(page);
212} 117}
213 118
214/* struct linked_page is used to build chains of pages */ 119/* struct linked_page is used to build chains of pages */
@@ -269,7 +174,7 @@ static void *chain_alloc(struct chain_allocator *ca, unsigned int size)
269 if (LINKED_PAGE_DATA_SIZE - ca->used_space < size) { 174 if (LINKED_PAGE_DATA_SIZE - ca->used_space < size) {
270 struct linked_page *lp; 175 struct linked_page *lp;
271 176
272 lp = alloc_image_page(ca->gfp_mask, ca->safe_needed); 177 lp = get_image_page(ca->gfp_mask, ca->safe_needed);
273 if (!lp) 178 if (!lp)
274 return NULL; 179 return NULL;
275 180
@@ -446,8 +351,8 @@ memory_bm_create(struct memory_bitmap *bm, gfp_t gfp_mask, int safe_needed)
446 351
447 /* Compute the number of zones */ 352 /* Compute the number of zones */
448 nr = 0; 353 nr = 0;
449 for_each_zone (zone) 354 for_each_zone(zone)
450 if (populated_zone(zone) && !is_highmem(zone)) 355 if (populated_zone(zone))
451 nr++; 356 nr++;
452 357
453 /* Allocate the list of zones bitmap objects */ 358 /* Allocate the list of zones bitmap objects */
@@ -459,10 +364,10 @@ memory_bm_create(struct memory_bitmap *bm, gfp_t gfp_mask, int safe_needed)
459 } 364 }
460 365
461 /* Initialize the zone bitmap objects */ 366 /* Initialize the zone bitmap objects */
462 for_each_zone (zone) { 367 for_each_zone(zone) {
463 unsigned long pfn; 368 unsigned long pfn;
464 369
465 if (!populated_zone(zone) || is_highmem(zone)) 370 if (!populated_zone(zone))
466 continue; 371 continue;
467 372
468 zone_bm->start_pfn = zone->zone_start_pfn; 373 zone_bm->start_pfn = zone->zone_start_pfn;
@@ -481,7 +386,7 @@ memory_bm_create(struct memory_bitmap *bm, gfp_t gfp_mask, int safe_needed)
481 while (bb) { 386 while (bb) {
482 unsigned long *ptr; 387 unsigned long *ptr;
483 388
484 ptr = alloc_image_page(gfp_mask, safe_needed); 389 ptr = get_image_page(gfp_mask, safe_needed);
485 bb->data = ptr; 390 bb->data = ptr;
486 if (!ptr) 391 if (!ptr)
487 goto Free; 392 goto Free;
@@ -669,9 +574,81 @@ unsigned int snapshot_additional_pages(struct zone *zone)
669 574
670 res = DIV_ROUND_UP(zone->spanned_pages, BM_BITS_PER_BLOCK); 575 res = DIV_ROUND_UP(zone->spanned_pages, BM_BITS_PER_BLOCK);
671 res += DIV_ROUND_UP(res * sizeof(struct bm_block), PAGE_SIZE); 576 res += DIV_ROUND_UP(res * sizeof(struct bm_block), PAGE_SIZE);
672 return res; 577 return 2 * res;
673} 578}
674 579
580#ifdef CONFIG_HIGHMEM
581/**
582 * count_free_highmem_pages - compute the total number of free highmem
583 * pages, system-wide.
584 */
585
586static unsigned int count_free_highmem_pages(void)
587{
588 struct zone *zone;
589 unsigned int cnt = 0;
590
591 for_each_zone(zone)
592 if (populated_zone(zone) && is_highmem(zone))
593 cnt += zone->free_pages;
594
595 return cnt;
596}
597
598/**
599 * saveable_highmem_page - Determine whether a highmem page should be
600 * included in the suspend image.
601 *
602 * We should save the page if it isn't Nosave or NosaveFree, or Reserved,
603 * and it isn't a part of a free chunk of pages.
604 */
605
606static struct page *saveable_highmem_page(unsigned long pfn)
607{
608 struct page *page;
609
610 if (!pfn_valid(pfn))
611 return NULL;
612
613 page = pfn_to_page(pfn);
614
615 BUG_ON(!PageHighMem(page));
616
617 if (PageNosave(page) || PageReserved(page) || PageNosaveFree(page))
618 return NULL;
619
620 return page;
621}
622
623/**
624 * count_highmem_pages - compute the total number of saveable highmem
625 * pages.
626 */
627
628unsigned int count_highmem_pages(void)
629{
630 struct zone *zone;
631 unsigned int n = 0;
632
633 for_each_zone(zone) {
634 unsigned long pfn, max_zone_pfn;
635
636 if (!is_highmem(zone))
637 continue;
638
639 mark_free_pages(zone);
640 max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
641 for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
642 if (saveable_highmem_page(pfn))
643 n++;
644 }
645 return n;
646}
647#else
648static inline void *saveable_highmem_page(unsigned long pfn) { return NULL; }
649static inline unsigned int count_highmem_pages(void) { return 0; }
650#endif /* CONFIG_HIGHMEM */
651
675/** 652/**
676 * pfn_is_nosave - check if given pfn is in the 'nosave' section 653 * pfn_is_nosave - check if given pfn is in the 'nosave' section
677 */ 654 */
@@ -684,12 +661,12 @@ static inline int pfn_is_nosave(unsigned long pfn)
684} 661}
685 662
686/** 663/**
687 * saveable - Determine whether a page should be cloned or not. 664 * saveable - Determine whether a non-highmem page should be included in
688 * @pfn: The page 665 * the suspend image.
689 * 666 *
690 * We save a page if it isn't Nosave, and is not in the range of pages 667 * We should save the page if it isn't Nosave, and is not in the range
691 * statically defined as 'unsaveable', and it 668 * of pages statically defined as 'unsaveable', and it isn't a part of
692 * isn't a part of a free chunk of pages. 669 * a free chunk of pages.
693 */ 670 */
694 671
695static struct page *saveable_page(unsigned long pfn) 672static struct page *saveable_page(unsigned long pfn)
@@ -701,76 +678,130 @@ static struct page *saveable_page(unsigned long pfn)
701 678
702 page = pfn_to_page(pfn); 679 page = pfn_to_page(pfn);
703 680
704 if (PageNosave(page)) 681 BUG_ON(PageHighMem(page));
682
683 if (PageNosave(page) || PageNosaveFree(page))
705 return NULL; 684 return NULL;
685
706 if (PageReserved(page) && pfn_is_nosave(pfn)) 686 if (PageReserved(page) && pfn_is_nosave(pfn))
707 return NULL; 687 return NULL;
708 if (PageNosaveFree(page))
709 return NULL;
710 688
711 return page; 689 return page;
712} 690}
713 691
692/**
693 * count_data_pages - compute the total number of saveable non-highmem
694 * pages.
695 */
696
714unsigned int count_data_pages(void) 697unsigned int count_data_pages(void)
715{ 698{
716 struct zone *zone; 699 struct zone *zone;
717 unsigned long pfn, max_zone_pfn; 700 unsigned long pfn, max_zone_pfn;
718 unsigned int n = 0; 701 unsigned int n = 0;
719 702
720 for_each_zone (zone) { 703 for_each_zone(zone) {
721 if (is_highmem(zone)) 704 if (is_highmem(zone))
722 continue; 705 continue;
706
723 mark_free_pages(zone); 707 mark_free_pages(zone);
724 max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; 708 max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
725 for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) 709 for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
726 n += !!saveable_page(pfn); 710 if(saveable_page(pfn))
711 n++;
727 } 712 }
728 return n; 713 return n;
729} 714}
730 715
731static inline void copy_data_page(long *dst, long *src) 716/* This is needed, because copy_page and memcpy are not usable for copying
717 * task structs.
718 */
719static inline void do_copy_page(long *dst, long *src)
732{ 720{
733 int n; 721 int n;
734 722
735 /* copy_page and memcpy are not usable for copying task structs. */
736 for (n = PAGE_SIZE / sizeof(long); n; n--) 723 for (n = PAGE_SIZE / sizeof(long); n; n--)
737 *dst++ = *src++; 724 *dst++ = *src++;
738} 725}
739 726
727#ifdef CONFIG_HIGHMEM
728static inline struct page *
729page_is_saveable(struct zone *zone, unsigned long pfn)
730{
731 return is_highmem(zone) ?
732 saveable_highmem_page(pfn) : saveable_page(pfn);
733}
734
735static inline void
736copy_data_page(unsigned long dst_pfn, unsigned long src_pfn)
737{
738 struct page *s_page, *d_page;
739 void *src, *dst;
740
741 s_page = pfn_to_page(src_pfn);
742 d_page = pfn_to_page(dst_pfn);
743 if (PageHighMem(s_page)) {
744 src = kmap_atomic(s_page, KM_USER0);
745 dst = kmap_atomic(d_page, KM_USER1);
746 do_copy_page(dst, src);
747 kunmap_atomic(src, KM_USER0);
748 kunmap_atomic(dst, KM_USER1);
749 } else {
750 src = page_address(s_page);
751 if (PageHighMem(d_page)) {
752 /* Page pointed to by src may contain some kernel
753 * data modified by kmap_atomic()
754 */
755 do_copy_page(buffer, src);
756 dst = kmap_atomic(pfn_to_page(dst_pfn), KM_USER0);
757 memcpy(dst, buffer, PAGE_SIZE);
758 kunmap_atomic(dst, KM_USER0);
759 } else {
760 dst = page_address(d_page);
761 do_copy_page(dst, src);
762 }
763 }
764}
765#else
766#define page_is_saveable(zone, pfn) saveable_page(pfn)
767
768static inline void
769copy_data_page(unsigned long dst_pfn, unsigned long src_pfn)
770{
771 do_copy_page(page_address(pfn_to_page(dst_pfn)),
772 page_address(pfn_to_page(src_pfn)));
773}
774#endif /* CONFIG_HIGHMEM */
775
740static void 776static void
741copy_data_pages(struct memory_bitmap *copy_bm, struct memory_bitmap *orig_bm) 777copy_data_pages(struct memory_bitmap *copy_bm, struct memory_bitmap *orig_bm)
742{ 778{
743 struct zone *zone; 779 struct zone *zone;
744 unsigned long pfn; 780 unsigned long pfn;
745 781
746 for_each_zone (zone) { 782 for_each_zone(zone) {
747 unsigned long max_zone_pfn; 783 unsigned long max_zone_pfn;
748 784
749 if (is_highmem(zone))
750 continue;
751
752 mark_free_pages(zone); 785 mark_free_pages(zone);
753 max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; 786 max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
754 for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) 787 for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
755 if (saveable_page(pfn)) 788 if (page_is_saveable(zone, pfn))
756 memory_bm_set_bit(orig_bm, pfn); 789 memory_bm_set_bit(orig_bm, pfn);
757 } 790 }
758 memory_bm_position_reset(orig_bm); 791 memory_bm_position_reset(orig_bm);
759 memory_bm_position_reset(copy_bm); 792 memory_bm_position_reset(copy_bm);
760 do { 793 do {
761 pfn = memory_bm_next_pfn(orig_bm); 794 pfn = memory_bm_next_pfn(orig_bm);
762 if (likely(pfn != BM_END_OF_MAP)) { 795 if (likely(pfn != BM_END_OF_MAP))
763 struct page *page; 796 copy_data_page(memory_bm_next_pfn(copy_bm), pfn);
764 void *src;
765
766 page = pfn_to_page(pfn);
767 src = page_address(page);
768 page = pfn_to_page(memory_bm_next_pfn(copy_bm));
769 copy_data_page(page_address(page), src);
770 }
771 } while (pfn != BM_END_OF_MAP); 797 } while (pfn != BM_END_OF_MAP);
772} 798}
773 799
800/* Total number of image pages */
801static unsigned int nr_copy_pages;
802/* Number of pages needed for saving the original pfns of the image pages */
803static unsigned int nr_meta_pages;
804
774/** 805/**
775 * swsusp_free - free pages allocated for the suspend. 806 * swsusp_free - free pages allocated for the suspend.
776 * 807 *
@@ -792,7 +823,7 @@ void swsusp_free(void)
792 if (PageNosave(page) && PageNosaveFree(page)) { 823 if (PageNosave(page) && PageNosaveFree(page)) {
793 ClearPageNosave(page); 824 ClearPageNosave(page);
794 ClearPageNosaveFree(page); 825 ClearPageNosaveFree(page);
795 free_page((long) page_address(page)); 826 __free_page(page);
796 } 827 }
797 } 828 }
798 } 829 }
@@ -802,34 +833,108 @@ void swsusp_free(void)
802 buffer = NULL; 833 buffer = NULL;
803} 834}
804 835
836#ifdef CONFIG_HIGHMEM
837/**
838 * count_pages_for_highmem - compute the number of non-highmem pages
839 * that will be necessary for creating copies of highmem pages.
840 */
841
842static unsigned int count_pages_for_highmem(unsigned int nr_highmem)
843{
844 unsigned int free_highmem = count_free_highmem_pages();
845
846 if (free_highmem >= nr_highmem)
847 nr_highmem = 0;
848 else
849 nr_highmem -= free_highmem;
850
851 return nr_highmem;
852}
853#else
854static unsigned int
855count_pages_for_highmem(unsigned int nr_highmem) { return 0; }
856#endif /* CONFIG_HIGHMEM */
805 857
806/** 858/**
807 * enough_free_mem - Make sure we enough free memory to snapshot. 859 * enough_free_mem - Make sure we have enough free memory for the
808 * 860 * snapshot image.
809 * Returns TRUE or FALSE after checking the number of available
810 * free pages.
811 */ 861 */
812 862
813static int enough_free_mem(unsigned int nr_pages) 863static int enough_free_mem(unsigned int nr_pages, unsigned int nr_highmem)
814{ 864{
815 struct zone *zone; 865 struct zone *zone;
816 unsigned int free = 0, meta = 0; 866 unsigned int free = 0, meta = 0;
817 867
818 for_each_zone (zone) 868 for_each_zone(zone) {
819 if (!is_highmem(zone)) { 869 meta += snapshot_additional_pages(zone);
870 if (!is_highmem(zone))
820 free += zone->free_pages; 871 free += zone->free_pages;
821 meta += snapshot_additional_pages(zone); 872 }
822 }
823 873
824 pr_debug("swsusp: pages needed: %u + %u + %u, available pages: %u\n", 874 nr_pages += count_pages_for_highmem(nr_highmem);
875 pr_debug("swsusp: Normal pages needed: %u + %u + %u, available pages: %u\n",
825 nr_pages, PAGES_FOR_IO, meta, free); 876 nr_pages, PAGES_FOR_IO, meta, free);
826 877
827 return free > nr_pages + PAGES_FOR_IO + meta; 878 return free > nr_pages + PAGES_FOR_IO + meta;
828} 879}
829 880
881#ifdef CONFIG_HIGHMEM
882/**
883 * get_highmem_buffer - if there are some highmem pages in the suspend
884 * image, we may need the buffer to copy them and/or load their data.
885 */
886
887static inline int get_highmem_buffer(int safe_needed)
888{
889 buffer = get_image_page(GFP_ATOMIC | __GFP_COLD, safe_needed);
890 return buffer ? 0 : -ENOMEM;
891}
892
893/**
894 * alloc_highmem_image_pages - allocate some highmem pages for the image.
895 * Try to allocate as many pages as needed, but if the number of free
896 * highmem pages is lesser than that, allocate them all.
897 */
898
899static inline unsigned int
900alloc_highmem_image_pages(struct memory_bitmap *bm, unsigned int nr_highmem)
901{
902 unsigned int to_alloc = count_free_highmem_pages();
903
904 if (to_alloc > nr_highmem)
905 to_alloc = nr_highmem;
906
907 nr_highmem -= to_alloc;
908 while (to_alloc-- > 0) {
909 struct page *page;
910
911 page = alloc_image_page(__GFP_HIGHMEM);
912 memory_bm_set_bit(bm, page_to_pfn(page));
913 }
914 return nr_highmem;
915}
916#else
917static inline int get_highmem_buffer(int safe_needed) { return 0; }
918
919static inline unsigned int
920alloc_highmem_image_pages(struct memory_bitmap *bm, unsigned int n) { return 0; }
921#endif /* CONFIG_HIGHMEM */
922
923/**
924 * swsusp_alloc - allocate memory for the suspend image
925 *
926 * We first try to allocate as many highmem pages as there are
927 * saveable highmem pages in the system. If that fails, we allocate
928 * non-highmem pages for the copies of the remaining highmem ones.
929 *
930 * In this approach it is likely that the copies of highmem pages will
931 * also be located in the high memory, because of the way in which
932 * copy_data_pages() works.
933 */
934
830static int 935static int
831swsusp_alloc(struct memory_bitmap *orig_bm, struct memory_bitmap *copy_bm, 936swsusp_alloc(struct memory_bitmap *orig_bm, struct memory_bitmap *copy_bm,
832 unsigned int nr_pages) 937 unsigned int nr_pages, unsigned int nr_highmem)
833{ 938{
834 int error; 939 int error;
835 940
@@ -841,13 +946,19 @@ swsusp_alloc(struct memory_bitmap *orig_bm, struct memory_bitmap *copy_bm,
841 if (error) 946 if (error)
842 goto Free; 947 goto Free;
843 948
949 if (nr_highmem > 0) {
950 error = get_highmem_buffer(PG_ANY);
951 if (error)
952 goto Free;
953
954 nr_pages += alloc_highmem_image_pages(copy_bm, nr_highmem);
955 }
844 while (nr_pages-- > 0) { 956 while (nr_pages-- > 0) {
845 struct page *page = alloc_page(GFP_ATOMIC | __GFP_COLD); 957 struct page *page = alloc_image_page(GFP_ATOMIC | __GFP_COLD);
958
846 if (!page) 959 if (!page)
847 goto Free; 960 goto Free;
848 961
849 SetPageNosave(page);
850 SetPageNosaveFree(page);
851 memory_bm_set_bit(copy_bm, page_to_pfn(page)); 962 memory_bm_set_bit(copy_bm, page_to_pfn(page));
852 } 963 }
853 return 0; 964 return 0;
@@ -857,30 +968,39 @@ Free:
857 return -ENOMEM; 968 return -ENOMEM;
858} 969}
859 970
860/* Memory bitmap used for marking saveable pages */ 971/* Memory bitmap used for marking saveable pages (during suspend) or the
972 * suspend image pages (during resume)
973 */
861static struct memory_bitmap orig_bm; 974static struct memory_bitmap orig_bm;
862/* Memory bitmap used for marking allocated pages that will contain the copies 975/* Memory bitmap used on suspend for marking allocated pages that will contain
863 * of saveable pages 976 * the copies of saveable pages. During resume it is initially used for
977 * marking the suspend image pages, but then its set bits are duplicated in
978 * @orig_bm and it is released. Next, on systems with high memory, it may be
979 * used for marking "safe" highmem pages, but it has to be reinitialized for
980 * this purpose.
864 */ 981 */
865static struct memory_bitmap copy_bm; 982static struct memory_bitmap copy_bm;
866 983
867asmlinkage int swsusp_save(void) 984asmlinkage int swsusp_save(void)
868{ 985{
869 unsigned int nr_pages; 986 unsigned int nr_pages, nr_highmem;
870 987
871 pr_debug("swsusp: critical section: \n"); 988 printk("swsusp: critical section: \n");
872 989
873 drain_local_pages(); 990 drain_local_pages();
874 nr_pages = count_data_pages(); 991 nr_pages = count_data_pages();
875 printk("swsusp: Need to copy %u pages\n", nr_pages); 992 nr_highmem = count_highmem_pages();
993 printk("swsusp: Need to copy %u pages\n", nr_pages + nr_highmem);
876 994
877 if (!enough_free_mem(nr_pages)) { 995 if (!enough_free_mem(nr_pages, nr_highmem)) {
878 printk(KERN_ERR "swsusp: Not enough free memory\n"); 996 printk(KERN_ERR "swsusp: Not enough free memory\n");
879 return -ENOMEM; 997 return -ENOMEM;
880 } 998 }
881 999
882 if (swsusp_alloc(&orig_bm, &copy_bm, nr_pages)) 1000 if (swsusp_alloc(&orig_bm, &copy_bm, nr_pages, nr_highmem)) {
1001 printk(KERN_ERR "swsusp: Memory allocation failed\n");
883 return -ENOMEM; 1002 return -ENOMEM;
1003 }
884 1004
885 /* During allocating of suspend pagedir, new cold pages may appear. 1005 /* During allocating of suspend pagedir, new cold pages may appear.
886 * Kill them. 1006 * Kill them.
@@ -894,10 +1014,12 @@ asmlinkage int swsusp_save(void)
894 * touch swap space! Except we must write out our image of course. 1014 * touch swap space! Except we must write out our image of course.
895 */ 1015 */
896 1016
1017 nr_pages += nr_highmem;
897 nr_copy_pages = nr_pages; 1018 nr_copy_pages = nr_pages;
898 nr_meta_pages = (nr_pages * sizeof(long) + PAGE_SIZE - 1) >> PAGE_SHIFT; 1019 nr_meta_pages = DIV_ROUND_UP(nr_pages * sizeof(long), PAGE_SIZE);
899 1020
900 printk("swsusp: critical section/: done (%d pages copied)\n", nr_pages); 1021 printk("swsusp: critical section/: done (%d pages copied)\n", nr_pages);
1022
901 return 0; 1023 return 0;
902} 1024}
903 1025
@@ -960,7 +1082,7 @@ int snapshot_read_next(struct snapshot_handle *handle, size_t count)
960 1082
961 if (!buffer) { 1083 if (!buffer) {
962 /* This makes the buffer be freed by swsusp_free() */ 1084 /* This makes the buffer be freed by swsusp_free() */
963 buffer = alloc_image_page(GFP_ATOMIC, PG_ANY); 1085 buffer = get_image_page(GFP_ATOMIC, PG_ANY);
964 if (!buffer) 1086 if (!buffer)
965 return -ENOMEM; 1087 return -ENOMEM;
966 } 1088 }
@@ -975,9 +1097,23 @@ int snapshot_read_next(struct snapshot_handle *handle, size_t count)
975 memset(buffer, 0, PAGE_SIZE); 1097 memset(buffer, 0, PAGE_SIZE);
976 pack_pfns(buffer, &orig_bm); 1098 pack_pfns(buffer, &orig_bm);
977 } else { 1099 } else {
978 unsigned long pfn = memory_bm_next_pfn(&copy_bm); 1100 struct page *page;
979 1101
980 handle->buffer = page_address(pfn_to_page(pfn)); 1102 page = pfn_to_page(memory_bm_next_pfn(&copy_bm));
1103 if (PageHighMem(page)) {
1104 /* Highmem pages are copied to the buffer,
1105 * because we can't return with a kmapped
1106 * highmem page (we may not be called again).
1107 */
1108 void *kaddr;
1109
1110 kaddr = kmap_atomic(page, KM_USER0);
1111 memcpy(buffer, kaddr, PAGE_SIZE);
1112 kunmap_atomic(kaddr, KM_USER0);
1113 handle->buffer = buffer;
1114 } else {
1115 handle->buffer = page_address(page);
1116 }
981 } 1117 }
982 handle->prev = handle->cur; 1118 handle->prev = handle->cur;
983 } 1119 }
@@ -1005,7 +1141,7 @@ static int mark_unsafe_pages(struct memory_bitmap *bm)
1005 unsigned long pfn, max_zone_pfn; 1141 unsigned long pfn, max_zone_pfn;
1006 1142
1007 /* Clear page flags */ 1143 /* Clear page flags */
1008 for_each_zone (zone) { 1144 for_each_zone(zone) {
1009 max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; 1145 max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
1010 for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) 1146 for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
1011 if (pfn_valid(pfn)) 1147 if (pfn_valid(pfn))
@@ -1101,6 +1237,218 @@ unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm)
1101 } 1237 }
1102} 1238}
1103 1239
1240/* List of "safe" pages that may be used to store data loaded from the suspend
1241 * image
1242 */
1243static struct linked_page *safe_pages_list;
1244
1245#ifdef CONFIG_HIGHMEM
1246/* struct highmem_pbe is used for creating the list of highmem pages that
1247 * should be restored atomically during the resume from disk, because the page
1248 * frames they have occupied before the suspend are in use.
1249 */
1250struct highmem_pbe {
1251 struct page *copy_page; /* data is here now */
1252 struct page *orig_page; /* data was here before the suspend */
1253 struct highmem_pbe *next;
1254};
1255
1256/* List of highmem PBEs needed for restoring the highmem pages that were
1257 * allocated before the suspend and included in the suspend image, but have
1258 * also been allocated by the "resume" kernel, so their contents cannot be
1259 * written directly to their "original" page frames.
1260 */
1261static struct highmem_pbe *highmem_pblist;
1262
1263/**
1264 * count_highmem_image_pages - compute the number of highmem pages in the
1265 * suspend image. The bits in the memory bitmap @bm that correspond to the
1266 * image pages are assumed to be set.
1267 */
1268
1269static unsigned int count_highmem_image_pages(struct memory_bitmap *bm)
1270{
1271 unsigned long pfn;
1272 unsigned int cnt = 0;
1273
1274 memory_bm_position_reset(bm);
1275 pfn = memory_bm_next_pfn(bm);
1276 while (pfn != BM_END_OF_MAP) {
1277 if (PageHighMem(pfn_to_page(pfn)))
1278 cnt++;
1279
1280 pfn = memory_bm_next_pfn(bm);
1281 }
1282 return cnt;
1283}
1284
1285/**
1286 * prepare_highmem_image - try to allocate as many highmem pages as
1287 * there are highmem image pages (@nr_highmem_p points to the variable
1288 * containing the number of highmem image pages). The pages that are
1289 * "safe" (ie. will not be overwritten when the suspend image is
1290 * restored) have the corresponding bits set in @bm (it must be
1291 * unitialized).
1292 *
1293 * NOTE: This function should not be called if there are no highmem
1294 * image pages.
1295 */
1296
1297static unsigned int safe_highmem_pages;
1298
1299static struct memory_bitmap *safe_highmem_bm;
1300
1301static int
1302prepare_highmem_image(struct memory_bitmap *bm, unsigned int *nr_highmem_p)
1303{
1304 unsigned int to_alloc;
1305
1306 if (memory_bm_create(bm, GFP_ATOMIC, PG_SAFE))
1307 return -ENOMEM;
1308
1309 if (get_highmem_buffer(PG_SAFE))
1310 return -ENOMEM;
1311
1312 to_alloc = count_free_highmem_pages();
1313 if (to_alloc > *nr_highmem_p)
1314 to_alloc = *nr_highmem_p;
1315 else
1316 *nr_highmem_p = to_alloc;
1317
1318 safe_highmem_pages = 0;
1319 while (to_alloc-- > 0) {
1320 struct page *page;
1321
1322 page = alloc_page(__GFP_HIGHMEM);
1323 if (!PageNosaveFree(page)) {
1324 /* The page is "safe", set its bit the bitmap */
1325 memory_bm_set_bit(bm, page_to_pfn(page));
1326 safe_highmem_pages++;
1327 }
1328 /* Mark the page as allocated */
1329 SetPageNosave(page);
1330 SetPageNosaveFree(page);
1331 }
1332 memory_bm_position_reset(bm);
1333 safe_highmem_bm = bm;
1334 return 0;
1335}
1336
1337/**
1338 * get_highmem_page_buffer - for given highmem image page find the buffer
1339 * that suspend_write_next() should set for its caller to write to.
1340 *
1341 * If the page is to be saved to its "original" page frame or a copy of
1342 * the page is to be made in the highmem, @buffer is returned. Otherwise,
1343 * the copy of the page is to be made in normal memory, so the address of
1344 * the copy is returned.
1345 *
1346 * If @buffer is returned, the caller of suspend_write_next() will write
1347 * the page's contents to @buffer, so they will have to be copied to the
1348 * right location on the next call to suspend_write_next() and it is done
1349 * with the help of copy_last_highmem_page(). For this purpose, if
1350 * @buffer is returned, @last_highmem page is set to the page to which
1351 * the data will have to be copied from @buffer.
1352 */
1353
1354static struct page *last_highmem_page;
1355
1356static void *
1357get_highmem_page_buffer(struct page *page, struct chain_allocator *ca)
1358{
1359 struct highmem_pbe *pbe;
1360 void *kaddr;
1361
1362 if (PageNosave(page) && PageNosaveFree(page)) {
1363 /* We have allocated the "original" page frame and we can
1364 * use it directly to store the loaded page.
1365 */
1366 last_highmem_page = page;
1367 return buffer;
1368 }
1369 /* The "original" page frame has not been allocated and we have to
1370 * use a "safe" page frame to store the loaded page.
1371 */
1372 pbe = chain_alloc(ca, sizeof(struct highmem_pbe));
1373 if (!pbe) {
1374 swsusp_free();
1375 return NULL;
1376 }
1377 pbe->orig_page = page;
1378 if (safe_highmem_pages > 0) {
1379 struct page *tmp;
1380
1381 /* Copy of the page will be stored in high memory */
1382 kaddr = buffer;
1383 tmp = pfn_to_page(memory_bm_next_pfn(safe_highmem_bm));
1384 safe_highmem_pages--;
1385 last_highmem_page = tmp;
1386 pbe->copy_page = tmp;
1387 } else {
1388 /* Copy of the page will be stored in normal memory */
1389 kaddr = safe_pages_list;
1390 safe_pages_list = safe_pages_list->next;
1391 pbe->copy_page = virt_to_page(kaddr);
1392 }
1393 pbe->next = highmem_pblist;
1394 highmem_pblist = pbe;
1395 return kaddr;
1396}
1397
1398/**
1399 * copy_last_highmem_page - copy the contents of a highmem image from
1400 * @buffer, where the caller of snapshot_write_next() has place them,
1401 * to the right location represented by @last_highmem_page .
1402 */
1403
1404static void copy_last_highmem_page(void)
1405{
1406 if (last_highmem_page) {
1407 void *dst;
1408
1409 dst = kmap_atomic(last_highmem_page, KM_USER0);
1410 memcpy(dst, buffer, PAGE_SIZE);
1411 kunmap_atomic(dst, KM_USER0);
1412 last_highmem_page = NULL;
1413 }
1414}
1415
1416static inline int last_highmem_page_copied(void)
1417{
1418 return !last_highmem_page;
1419}
1420
1421static inline void free_highmem_data(void)
1422{
1423 if (safe_highmem_bm)
1424 memory_bm_free(safe_highmem_bm, PG_UNSAFE_CLEAR);
1425
1426 if (buffer)
1427 free_image_page(buffer, PG_UNSAFE_CLEAR);
1428}
1429#else
1430static inline int get_safe_write_buffer(void) { return 0; }
1431
1432static unsigned int
1433count_highmem_image_pages(struct memory_bitmap *bm) { return 0; }
1434
1435static inline int
1436prepare_highmem_image(struct memory_bitmap *bm, unsigned int *nr_highmem_p)
1437{
1438 return 0;
1439}
1440
1441static inline void *
1442get_highmem_page_buffer(struct page *page, struct chain_allocator *ca)
1443{
1444 return NULL;
1445}
1446
1447static inline void copy_last_highmem_page(void) {}
1448static inline int last_highmem_page_copied(void) { return 1; }
1449static inline void free_highmem_data(void) {}
1450#endif /* CONFIG_HIGHMEM */
1451
1104/** 1452/**
1105 * prepare_image - use the memory bitmap @bm to mark the pages that will 1453 * prepare_image - use the memory bitmap @bm to mark the pages that will
1106 * be overwritten in the process of restoring the system memory state 1454 * be overwritten in the process of restoring the system memory state
@@ -1110,20 +1458,25 @@ unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm)
1110 * The idea is to allocate a new memory bitmap first and then allocate 1458 * The idea is to allocate a new memory bitmap first and then allocate
1111 * as many pages as needed for the image data, but not to assign these 1459 * as many pages as needed for the image data, but not to assign these
1112 * pages to specific tasks initially. Instead, we just mark them as 1460 * pages to specific tasks initially. Instead, we just mark them as
1113 * allocated and create a list of "safe" pages that will be used later. 1461 * allocated and create a lists of "safe" pages that will be used
1462 * later. On systems with high memory a list of "safe" highmem pages is
1463 * also created.
1114 */ 1464 */
1115 1465
1116#define PBES_PER_LINKED_PAGE (LINKED_PAGE_DATA_SIZE / sizeof(struct pbe)) 1466#define PBES_PER_LINKED_PAGE (LINKED_PAGE_DATA_SIZE / sizeof(struct pbe))
1117 1467
1118static struct linked_page *safe_pages_list;
1119
1120static int 1468static int
1121prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm) 1469prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm)
1122{ 1470{
1123 unsigned int nr_pages; 1471 unsigned int nr_pages, nr_highmem;
1124 struct linked_page *sp_list, *lp; 1472 struct linked_page *sp_list, *lp;
1125 int error; 1473 int error;
1126 1474
1475 /* If there is no highmem, the buffer will not be necessary */
1476 free_image_page(buffer, PG_UNSAFE_CLEAR);
1477 buffer = NULL;
1478
1479 nr_highmem = count_highmem_image_pages(bm);
1127 error = mark_unsafe_pages(bm); 1480 error = mark_unsafe_pages(bm);
1128 if (error) 1481 if (error)
1129 goto Free; 1482 goto Free;
@@ -1134,6 +1487,11 @@ prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm)
1134 1487
1135 duplicate_memory_bitmap(new_bm, bm); 1488 duplicate_memory_bitmap(new_bm, bm);
1136 memory_bm_free(bm, PG_UNSAFE_KEEP); 1489 memory_bm_free(bm, PG_UNSAFE_KEEP);
1490 if (nr_highmem > 0) {
1491 error = prepare_highmem_image(bm, &nr_highmem);
1492 if (error)
1493 goto Free;
1494 }
1137 /* Reserve some safe pages for potential later use. 1495 /* Reserve some safe pages for potential later use.
1138 * 1496 *
1139 * NOTE: This way we make sure there will be enough safe pages for the 1497 * NOTE: This way we make sure there will be enough safe pages for the
@@ -1142,10 +1500,10 @@ prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm)
1142 */ 1500 */
1143 sp_list = NULL; 1501 sp_list = NULL;
1144 /* nr_copy_pages cannot be lesser than allocated_unsafe_pages */ 1502 /* nr_copy_pages cannot be lesser than allocated_unsafe_pages */
1145 nr_pages = nr_copy_pages - allocated_unsafe_pages; 1503 nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages;
1146 nr_pages = DIV_ROUND_UP(nr_pages, PBES_PER_LINKED_PAGE); 1504 nr_pages = DIV_ROUND_UP(nr_pages, PBES_PER_LINKED_PAGE);
1147 while (nr_pages > 0) { 1505 while (nr_pages > 0) {
1148 lp = alloc_image_page(GFP_ATOMIC, PG_SAFE); 1506 lp = get_image_page(GFP_ATOMIC, PG_SAFE);
1149 if (!lp) { 1507 if (!lp) {
1150 error = -ENOMEM; 1508 error = -ENOMEM;
1151 goto Free; 1509 goto Free;
@@ -1156,7 +1514,7 @@ prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm)
1156 } 1514 }
1157 /* Preallocate memory for the image */ 1515 /* Preallocate memory for the image */
1158 safe_pages_list = NULL; 1516 safe_pages_list = NULL;
1159 nr_pages = nr_copy_pages - allocated_unsafe_pages; 1517 nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages;
1160 while (nr_pages > 0) { 1518 while (nr_pages > 0) {
1161 lp = (struct linked_page *)get_zeroed_page(GFP_ATOMIC); 1519 lp = (struct linked_page *)get_zeroed_page(GFP_ATOMIC);
1162 if (!lp) { 1520 if (!lp) {
@@ -1196,6 +1554,9 @@ static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca)
1196 struct pbe *pbe; 1554 struct pbe *pbe;
1197 struct page *page = pfn_to_page(memory_bm_next_pfn(bm)); 1555 struct page *page = pfn_to_page(memory_bm_next_pfn(bm));
1198 1556
1557 if (PageHighMem(page))
1558 return get_highmem_page_buffer(page, ca);
1559
1199 if (PageNosave(page) && PageNosaveFree(page)) 1560 if (PageNosave(page) && PageNosaveFree(page))
1200 /* We have allocated the "original" page frame and we can 1561 /* We have allocated the "original" page frame and we can
1201 * use it directly to store the loaded page. 1562 * use it directly to store the loaded page.
@@ -1210,12 +1571,12 @@ static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca)
1210 swsusp_free(); 1571 swsusp_free();
1211 return NULL; 1572 return NULL;
1212 } 1573 }
1213 pbe->orig_address = (unsigned long)page_address(page); 1574 pbe->orig_address = page_address(page);
1214 pbe->address = (unsigned long)safe_pages_list; 1575 pbe->address = safe_pages_list;
1215 safe_pages_list = safe_pages_list->next; 1576 safe_pages_list = safe_pages_list->next;
1216 pbe->next = restore_pblist; 1577 pbe->next = restore_pblist;
1217 restore_pblist = pbe; 1578 restore_pblist = pbe;
1218 return (void *)pbe->address; 1579 return pbe->address;
1219} 1580}
1220 1581
1221/** 1582/**
@@ -1249,14 +1610,16 @@ int snapshot_write_next(struct snapshot_handle *handle, size_t count)
1249 if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages) 1610 if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages)
1250 return 0; 1611 return 0;
1251 1612
1252 if (!buffer) { 1613 if (handle->offset == 0) {
1253 /* This makes the buffer be freed by swsusp_free() */ 1614 if (!buffer)
1254 buffer = alloc_image_page(GFP_ATOMIC, PG_ANY); 1615 /* This makes the buffer be freed by swsusp_free() */
1616 buffer = get_image_page(GFP_ATOMIC, PG_ANY);
1617
1255 if (!buffer) 1618 if (!buffer)
1256 return -ENOMEM; 1619 return -ENOMEM;
1257 } 1620
1258 if (!handle->offset)
1259 handle->buffer = buffer; 1621 handle->buffer = buffer;
1622 }
1260 handle->sync_read = 1; 1623 handle->sync_read = 1;
1261 if (handle->prev < handle->cur) { 1624 if (handle->prev < handle->cur) {
1262 if (handle->prev == 0) { 1625 if (handle->prev == 0) {
@@ -1284,8 +1647,10 @@ int snapshot_write_next(struct snapshot_handle *handle, size_t count)
1284 return -ENOMEM; 1647 return -ENOMEM;
1285 } 1648 }
1286 } else { 1649 } else {
1650 copy_last_highmem_page();
1287 handle->buffer = get_buffer(&orig_bm, &ca); 1651 handle->buffer = get_buffer(&orig_bm, &ca);
1288 handle->sync_read = 0; 1652 if (handle->buffer != buffer)
1653 handle->sync_read = 0;
1289 } 1654 }
1290 handle->prev = handle->cur; 1655 handle->prev = handle->cur;
1291 } 1656 }
@@ -1301,15 +1666,73 @@ int snapshot_write_next(struct snapshot_handle *handle, size_t count)
1301 return count; 1666 return count;
1302} 1667}
1303 1668
1669/**
1670 * snapshot_write_finalize - must be called after the last call to
1671 * snapshot_write_next() in case the last page in the image happens
1672 * to be a highmem page and its contents should be stored in the
1673 * highmem. Additionally, it releases the memory that will not be
1674 * used any more.
1675 */
1676
1677void snapshot_write_finalize(struct snapshot_handle *handle)
1678{
1679 copy_last_highmem_page();
1680 /* Free only if we have loaded the image entirely */
1681 if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages) {
1682 memory_bm_free(&orig_bm, PG_UNSAFE_CLEAR);
1683 free_highmem_data();
1684 }
1685}
1686
1304int snapshot_image_loaded(struct snapshot_handle *handle) 1687int snapshot_image_loaded(struct snapshot_handle *handle)
1305{ 1688{
1306 return !(!nr_copy_pages || 1689 return !(!nr_copy_pages || !last_highmem_page_copied() ||
1307 handle->cur <= nr_meta_pages + nr_copy_pages); 1690 handle->cur <= nr_meta_pages + nr_copy_pages);
1308} 1691}
1309 1692
1310void snapshot_free_unused_memory(struct snapshot_handle *handle) 1693#ifdef CONFIG_HIGHMEM
1694/* Assumes that @buf is ready and points to a "safe" page */
1695static inline void
1696swap_two_pages_data(struct page *p1, struct page *p2, void *buf)
1311{ 1697{
1312 /* Free only if we have loaded the image entirely */ 1698 void *kaddr1, *kaddr2;
1313 if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages) 1699
1314 memory_bm_free(&orig_bm, PG_UNSAFE_CLEAR); 1700 kaddr1 = kmap_atomic(p1, KM_USER0);
1701 kaddr2 = kmap_atomic(p2, KM_USER1);
1702 memcpy(buf, kaddr1, PAGE_SIZE);
1703 memcpy(kaddr1, kaddr2, PAGE_SIZE);
1704 memcpy(kaddr2, buf, PAGE_SIZE);
1705 kunmap_atomic(kaddr1, KM_USER0);
1706 kunmap_atomic(kaddr2, KM_USER1);
1707}
1708
1709/**
1710 * restore_highmem - for each highmem page that was allocated before
1711 * the suspend and included in the suspend image, and also has been
1712 * allocated by the "resume" kernel swap its current (ie. "before
1713 * resume") contents with the previous (ie. "before suspend") one.
1714 *
1715 * If the resume eventually fails, we can call this function once
1716 * again and restore the "before resume" highmem state.
1717 */
1718
1719int restore_highmem(void)
1720{
1721 struct highmem_pbe *pbe = highmem_pblist;
1722 void *buf;
1723
1724 if (!pbe)
1725 return 0;
1726
1727 buf = get_image_page(GFP_ATOMIC, PG_SAFE);
1728 if (!buf)
1729 return -ENOMEM;
1730
1731 while (pbe) {
1732 swap_two_pages_data(pbe->copy_page, pbe->orig_page, buf);
1733 pbe = pbe->next;
1734 }
1735 free_image_page(buf, PG_UNSAFE_CLEAR);
1736 return 0;
1315} 1737}
1738#endif /* CONFIG_HIGHMEM */