+++ /dev/null
-From: Rafael J. Wysocki <rjw@suse.de>
-Subject: Hibernate: Take overlapping zones into account (rev. 2)
-References: bnc#438914
-Patch-mainline: 846705deb059c352cc0e5806d5964f815b8c6d98
-
-It has been requested to make hibernation work with memory
-hotplugging enabled and for this purpose the hibernation code has to
-be reworked to take the possible overlapping of zones into account.
-Thus, rework the hibernation memory bitmaps code to prevent
-duplication of PFNs from occuring and add checks to make sure that
-one page frame will not be marked as saveable many times.
-
-Additionally, use list.h lists instead of open-coded lists to
-implement the memory bitmaps.
-
-Signed-off-by: Rafael J. Wysocki <rjw@suse.de>
----
- kernel/power/snapshot.c | 327 ++++++++++++++++++++++++------------------------
- 1 file changed, 167 insertions(+), 160 deletions(-)
-
-Index: linux-2.6.27/kernel/power/snapshot.c
-===================================================================
---- linux-2.6.27.orig/kernel/power/snapshot.c
-+++ linux-2.6.27/kernel/power/snapshot.c
-@@ -25,6 +25,7 @@
- #include <linux/syscalls.h>
- #include <linux/console.h>
- #include <linux/highmem.h>
-+#include <linux/list.h>
-
- #include <asm/uaccess.h>
- #include <asm/mmu_context.h>
-@@ -192,12 +193,6 @@ static void *chain_alloc(struct chain_al
- return ret;
- }
-
--static void chain_free(struct chain_allocator *ca, int clear_page_nosave)
--{
-- free_list_of_pages(ca->chain, clear_page_nosave);
-- memset(ca, 0, sizeof(struct chain_allocator));
--}
--
- /**
- * Data types related to memory bitmaps.
- *
-@@ -233,7 +228,7 @@ static void chain_free(struct chain_allo
- #define BM_BITS_PER_BLOCK (PAGE_SIZE << 3)
-
- struct bm_block {
-- struct bm_block *next; /* next element of the list */
-+ struct list_head hook; /* hook into a list of bitmap blocks */
- unsigned long start_pfn; /* pfn represented by the first bit */
- unsigned long end_pfn; /* pfn represented by the last bit plus 1 */
- unsigned long *data; /* bitmap representing pages */
-@@ -244,24 +239,15 @@ static inline unsigned long bm_block_bit
- return bb->end_pfn - bb->start_pfn;
- }
-
--struct zone_bitmap {
-- struct zone_bitmap *next; /* next element of the list */
-- unsigned long start_pfn; /* minimal pfn in this zone */
-- unsigned long end_pfn; /* maximal pfn in this zone plus 1 */
-- struct bm_block *bm_blocks; /* list of bitmap blocks */
-- struct bm_block *cur_block; /* recently used bitmap block */
--};
--
- /* strcut bm_position is used for browsing memory bitmaps */
-
- struct bm_position {
-- struct zone_bitmap *zone_bm;
- struct bm_block *block;
- int bit;
- };
-
- struct memory_bitmap {
-- struct zone_bitmap *zone_bm_list; /* list of zone bitmaps */
-+ struct list_head blocks; /* list of bitmap blocks */
- struct linked_page *p_list; /* list of pages used to store zone
- * bitmap objects and bitmap block
- * objects
-@@ -273,11 +259,7 @@ struct memory_bitmap {
-
- static void memory_bm_position_reset(struct memory_bitmap *bm)
- {
-- struct zone_bitmap *zone_bm;
--
-- zone_bm = bm->zone_bm_list;
-- bm->cur.zone_bm = zone_bm;
-- bm->cur.block = zone_bm->bm_blocks;
-+ bm->cur.block = list_entry(bm->blocks.next, struct bm_block, hook);
- bm->cur.bit = 0;
- }
-
-@@ -285,151 +267,184 @@ static void memory_bm_free(struct memory
-
- /**
- * create_bm_block_list - create a list of block bitmap objects
-- */
--
--static inline struct bm_block *
--create_bm_block_list(unsigned int nr_blocks, struct chain_allocator *ca)
-+ * @nr_blocks - number of blocks to allocate
-+ * @list - list to put the allocated blocks into
-+ * @ca - chain allocator to be used for allocating memory
-+ */
-+static int create_bm_block_list(unsigned long pages,
-+ struct list_head *list,
-+ struct chain_allocator *ca)
- {
-- struct bm_block *bblist = NULL;
-+ unsigned int nr_blocks = DIV_ROUND_UP(pages, BM_BITS_PER_BLOCK);
-
- while (nr_blocks-- > 0) {
- struct bm_block *bb;
-
- bb = chain_alloc(ca, sizeof(struct bm_block));
- if (!bb)
-- return NULL;
--
-- bb->next = bblist;
-- bblist = bb;
-+ return -ENOMEM;
-+ list_add(&bb->hook, list);
- }
-- return bblist;
-+
-+ return 0;
- }
-
-+struct mem_extent {
-+ struct list_head hook;
-+ unsigned long start;
-+ unsigned long end;
-+};
-+
- /**
-- * create_zone_bm_list - create a list of zone bitmap objects
-+ * free_mem_extents - free a list of memory extents
-+ * @list - list of extents to empty
- */
-+static void free_mem_extents(struct list_head *list)
-+{
-+ struct mem_extent *ext, *aux;
-
--static inline struct zone_bitmap *
--create_zone_bm_list(unsigned int nr_zones, struct chain_allocator *ca)
-+ list_for_each_entry_safe(ext, aux, list, hook) {
-+ list_del(&ext->hook);
-+ kfree(ext);
-+ }
-+}
-+
-+/**
-+ * create_mem_extents - create a list of memory extents representing
-+ * contiguous ranges of PFNs
-+ * @list - list to put the extents into
-+ * @gfp_mask - mask to use for memory allocations
-+ */
-+static int create_mem_extents(struct list_head *list, gfp_t gfp_mask)
- {
-- struct zone_bitmap *zbmlist = NULL;
-+ struct zone *zone;
-
-- while (nr_zones-- > 0) {
-- struct zone_bitmap *zbm;
-+ INIT_LIST_HEAD(list);
-
-- zbm = chain_alloc(ca, sizeof(struct zone_bitmap));
-- if (!zbm)
-- return NULL;
-+ for_each_zone(zone) {
-+ unsigned long zone_start, zone_end;
-+ struct mem_extent *ext, *cur, *aux;
-+
-+ if (!populated_zone(zone))
-+ continue;
-+
-+ zone_start = zone->zone_start_pfn;
-+ zone_end = zone->zone_start_pfn + zone->spanned_pages;
-+
-+ list_for_each_entry(ext, list, hook)
-+ if (zone_start <= ext->end)
-+ break;
-+
-+ if (&ext->hook == list || zone_end < ext->start) {
-+ /* New extent is necessary */
-+ struct mem_extent *new_ext;
-+
-+ new_ext = kzalloc(sizeof(struct mem_extent), gfp_mask);
-+ if (!new_ext) {
-+ free_mem_extents(list);
-+ return -ENOMEM;
-+ }
-+ new_ext->start = zone_start;
-+ new_ext->end = zone_end;
-+ list_add_tail(&new_ext->hook, &ext->hook);
-+ continue;
-+ }
-
-- zbm->next = zbmlist;
-- zbmlist = zbm;
-+ /* Merge this zone's range of PFNs with the existing one */
-+ if (zone_start < ext->start)
-+ ext->start = zone_start;
-+ if (zone_end > ext->end)
-+ ext->end = zone_end;
-+
-+ /* More merging may be possible */
-+ cur = ext;
-+ list_for_each_entry_safe_continue(cur, aux, list, hook) {
-+ if (zone_end < cur->start)
-+ break;
-+ if (zone_end < cur->end)
-+ ext->end = cur->end;
-+ list_del(&cur->hook);
-+ kfree(cur);
-+ }
- }
-- return zbmlist;
-+
-+ return 0;
- }
-
- /**
- * memory_bm_create - allocate memory for a memory bitmap
- */
--
- static int
- memory_bm_create(struct memory_bitmap *bm, gfp_t gfp_mask, int safe_needed)
- {
- struct chain_allocator ca;
-- struct zone *zone;
-- struct zone_bitmap *zone_bm;
-- struct bm_block *bb;
-- unsigned int nr;
-+ struct list_head mem_extents;
-+ struct mem_extent *ext;
-+ int error;
-
- chain_init(&ca, gfp_mask, safe_needed);
-+ INIT_LIST_HEAD(&bm->blocks);
-
-- /* Compute the number of zones */
-- nr = 0;
-- for_each_zone(zone)
-- if (populated_zone(zone))
-- nr++;
--
-- /* Allocate the list of zones bitmap objects */
-- zone_bm = create_zone_bm_list(nr, &ca);
-- bm->zone_bm_list = zone_bm;
-- if (!zone_bm) {
-- chain_free(&ca, PG_UNSAFE_CLEAR);
-- return -ENOMEM;
-- }
-+ error = create_mem_extents(&mem_extents, gfp_mask);
-+ if (error)
-+ return error;
-
-- /* Initialize the zone bitmap objects */
-- for_each_zone(zone) {
-- unsigned long pfn;
-+ list_for_each_entry(ext, &mem_extents, hook) {
-+ struct bm_block *bb;
-+ unsigned long pfn = ext->start;
-+ unsigned long pages = ext->end - ext->start;
-
-- if (!populated_zone(zone))
-- continue;
-+ bb = list_entry(bm->blocks.prev, struct bm_block, hook);
-
-- zone_bm->start_pfn = zone->zone_start_pfn;
-- zone_bm->end_pfn = zone->zone_start_pfn + zone->spanned_pages;
-- /* Allocate the list of bitmap block objects */
-- nr = DIV_ROUND_UP(zone->spanned_pages, BM_BITS_PER_BLOCK);
-- bb = create_bm_block_list(nr, &ca);
-- zone_bm->bm_blocks = bb;
-- zone_bm->cur_block = bb;
-- if (!bb)
-- goto Free;
-+ error = create_bm_block_list(pages, bm->blocks.prev, &ca);
-+ if (error)
-+ goto Error;
-
-- nr = zone->spanned_pages;
-- pfn = zone->zone_start_pfn;
-- /* Initialize the bitmap block objects */
-- while (bb) {
-- unsigned long *ptr;
--
-- ptr = get_image_page(gfp_mask, safe_needed);
-- bb->data = ptr;
-- if (!ptr)
-- goto Free;
-+ list_for_each_entry_continue(bb, &bm->blocks, hook) {
-+ bb->data = get_image_page(gfp_mask, safe_needed);
-+ if (!bb->data) {
-+ error = -ENOMEM;
-+ goto Error;
-+ }
-
- bb->start_pfn = pfn;
-- if (nr >= BM_BITS_PER_BLOCK) {
-+ if (pages >= BM_BITS_PER_BLOCK) {
- pfn += BM_BITS_PER_BLOCK;
-- nr -= BM_BITS_PER_BLOCK;
-+ pages -= BM_BITS_PER_BLOCK;
- } else {
- /* This is executed only once in the loop */
-- pfn += nr;
-+ pfn += pages;
- }
- bb->end_pfn = pfn;
-- bb = bb->next;
- }
-- zone_bm = zone_bm->next;
- }
-+
- bm->p_list = ca.chain;
- memory_bm_position_reset(bm);
-- return 0;
-+ Exit:
-+ free_mem_extents(&mem_extents);
-+ return error;
-
-- Free:
-+ Error:
- bm->p_list = ca.chain;
- memory_bm_free(bm, PG_UNSAFE_CLEAR);
-- return -ENOMEM;
-+ goto Exit;
- }
-
- /**
- * memory_bm_free - free memory occupied by the memory bitmap @bm
- */
--
- static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free)
- {
-- struct zone_bitmap *zone_bm;
-+ struct bm_block *bb;
-
-- /* Free the list of bit blocks for each zone_bitmap object */
-- zone_bm = bm->zone_bm_list;
-- while (zone_bm) {
-- struct bm_block *bb;
-+ list_for_each_entry(bb, &bm->blocks, hook)
-+ if (bb->data)
-+ free_image_page(bb->data, clear_nosave_free);
-
-- bb = zone_bm->bm_blocks;
-- while (bb) {
-- if (bb->data)
-- free_image_page(bb->data, clear_nosave_free);
-- bb = bb->next;
-- }
-- zone_bm = zone_bm->next;
-- }
- free_list_of_pages(bm->p_list, clear_nosave_free);
-- bm->zone_bm_list = NULL;
-+
-+ INIT_LIST_HEAD(&bm->blocks);
- }
-
- /**
-@@ -437,38 +452,33 @@ static void memory_bm_free(struct memory
- * to given pfn. The cur_zone_bm member of @bm and the cur_block member
- * of @bm->cur_zone_bm are updated.
- */
--
- static int memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
- void **addr, unsigned int *bit_nr)
- {
-- struct zone_bitmap *zone_bm;
- struct bm_block *bb;
-
-- /* Check if the pfn is from the current zone */
-- zone_bm = bm->cur.zone_bm;
-- if (pfn < zone_bm->start_pfn || pfn >= zone_bm->end_pfn) {
-- zone_bm = bm->zone_bm_list;
-- /* We don't assume that the zones are sorted by pfns */
-- while (pfn < zone_bm->start_pfn || pfn >= zone_bm->end_pfn) {
-- zone_bm = zone_bm->next;
--
-- if (!zone_bm)
-- return -EFAULT;
-- }
-- bm->cur.zone_bm = zone_bm;
-- }
-- /* Check if the pfn corresponds to the current bitmap block */
-- bb = zone_bm->cur_block;
-+ /*
-+ * Check if the pfn corresponds to the current bitmap block and find
-+ * the block where it fits if this is not the case.
-+ */
-+ bb = bm->cur.block;
- if (pfn < bb->start_pfn)
-- bb = zone_bm->bm_blocks;
-+ list_for_each_entry_continue_reverse(bb, &bm->blocks, hook)
-+ if (pfn >= bb->start_pfn)
-+ break;
-+
-+ if (pfn >= bb->end_pfn)
-+ list_for_each_entry_continue(bb, &bm->blocks, hook)
-+ if (pfn >= bb->start_pfn && pfn < bb->end_pfn)
-+ break;
-
-- while (pfn >= bb->end_pfn) {
-- bb = bb->next;
-+ if (&bb->hook == &bm->blocks)
-+ return -EFAULT;
-
-- BUG_ON(!bb);
-- }
-- zone_bm->cur_block = bb;
-+ /* The block has been found */
-+ bm->cur.block = bb;
- pfn -= bb->start_pfn;
-+ bm->cur.bit = pfn + 1;
- *bit_nr = pfn;
- *addr = bb->data;
- return 0;
-@@ -530,29 +540,21 @@ static int memory_bm_test_bit(struct mem
-
- static unsigned long memory_bm_next_pfn(struct memory_bitmap *bm)
- {
-- struct zone_bitmap *zone_bm;
- struct bm_block *bb;
- int bit;
-
-+ bb = bm->cur.block;
- do {
-- bb = bm->cur.block;
-- do {
-- bit = bm->cur.bit;
-- bit = find_next_bit(bb->data, bm_block_bits(bb), bit);
-- if (bit < bm_block_bits(bb))
-- goto Return_pfn;
--
-- bb = bb->next;
-- bm->cur.block = bb;
-- bm->cur.bit = 0;
-- } while (bb);
-- zone_bm = bm->cur.zone_bm->next;
-- if (zone_bm) {
-- bm->cur.zone_bm = zone_bm;
-- bm->cur.block = zone_bm->bm_blocks;
-- bm->cur.bit = 0;
-- }
-- } while (zone_bm);
-+ bit = bm->cur.bit;
-+ bit = find_next_bit(bb->data, bm_block_bits(bb), bit);
-+ if (bit < bm_block_bits(bb))
-+ goto Return_pfn;
-+
-+ bb = list_entry(bb->hook.next, struct bm_block, hook);
-+ bm->cur.block = bb;
-+ bm->cur.bit = 0;
-+ } while (&bb->hook != &bm->blocks);
-+
- memory_bm_position_reset(bm);
- return BM_END_OF_MAP;
-
-@@ -808,8 +810,7 @@ static unsigned int count_free_highmem_p
- * We should save the page if it isn't Nosave or NosaveFree, or Reserved,
- * and it isn't a part of a free chunk of pages.
- */
--
--static struct page *saveable_highmem_page(unsigned long pfn)
-+static struct page *saveable_highmem_page(struct zone *zone, unsigned long pfn)
- {
- struct page *page;
-
-@@ -817,6 +818,8 @@ static struct page *saveable_highmem_pag
- return NULL;
-
- page = pfn_to_page(pfn);
-+ if (page_zone(page) != zone)
-+ return NULL;
-
- BUG_ON(!PageHighMem(page));
-
-@@ -846,13 +849,16 @@ unsigned int count_highmem_pages(void)
- mark_free_pages(zone);
- max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
- for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
-- if (saveable_highmem_page(pfn))
-+ if (saveable_highmem_page(zone, pfn))
- n++;
- }
- return n;
- }
- #else
--static inline void *saveable_highmem_page(unsigned long pfn) { return NULL; }
-+static inline void *saveable_highmem_page(struct zone *z, unsigned long p)
-+{
-+ return NULL;
-+}
- #endif /* CONFIG_HIGHMEM */
-
- /**
-@@ -863,8 +869,7 @@ static inline void *saveable_highmem_pag
- * of pages statically defined as 'unsaveable', and it isn't a part of
- * a free chunk of pages.
- */
--
--static struct page *saveable_page(unsigned long pfn)
-+static struct page *saveable_page(struct zone *zone, unsigned long pfn)
- {
- struct page *page;
-
-@@ -872,6 +877,8 @@ static struct page *saveable_page(unsign
- return NULL;
-
- page = pfn_to_page(pfn);
-+ if (page_zone(page) != zone)
-+ return NULL;
-
- BUG_ON(PageHighMem(page));
-
-@@ -903,7 +910,7 @@ unsigned int count_data_pages(void)
- mark_free_pages(zone);
- max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
- for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
-- if(saveable_page(pfn))
-+ if (saveable_page(zone, pfn))
- n++;
- }
- return n;
-@@ -944,7 +951,7 @@ static inline struct page *
- page_is_saveable(struct zone *zone, unsigned long pfn)
- {
- return is_highmem(zone) ?
-- saveable_highmem_page(pfn) : saveable_page(pfn);
-+ saveable_highmem_page(zone, pfn) : saveable_page(zone, pfn);
- }
-
- static void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn)
-@@ -975,7 +982,7 @@ static void copy_data_page(unsigned long
- }
- }
- #else
--#define page_is_saveable(zone, pfn) saveable_page(pfn)
-+#define page_is_saveable(zone, pfn) saveable_page(zone, pfn)
-
- static inline void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn)
- {
projects / people / teissler / ipfire-2.x.git / blobdiff