* objects. The main list's elements are of type struct zone_bitmap
* and each of them corresonds to one zone. For each zone bitmap
* object there is a list of objects of type struct bm_block that
- * represent each blocks of bit chunks in which information is
- * stored.
+ * represent each blocks of bitmap in which information is stored.
*
* struct memory_bitmap contains a pointer to the main list of zone
* bitmap objects, a struct bm_position used for browsing the bitmap,
* pfns that correspond to the start and end of the represented zone.
*
* struct bm_block contains a pointer to the memory page in which
- * information is stored (in the form of a block of bit chunks
- * of type unsigned long each). It also contains the pfns that
- * correspond to the start and end of the represented memory area and
- * the number of bit chunks in the block.
+ * information is stored (in the form of a block of bitmap)
+ * It also contains the pfns that correspond to the start and end of
+ * the represented memory area.
*/
#define BM_END_OF_MAP (~0UL)
-#define BM_CHUNKS_PER_BLOCK (PAGE_SIZE / sizeof(long))
-#define BM_BITS_PER_CHUNK (sizeof(long) << 3)
#define BM_BITS_PER_BLOCK (PAGE_SIZE << 3)
struct bm_block {
struct bm_block *next; /* next element of the list */
unsigned long start_pfn; /* pfn represented by the first bit */
unsigned long end_pfn; /* pfn represented by the last bit plus 1 */
- unsigned int size; /* number of bit chunks */
- unsigned long *data; /* chunks of bits representing pages */
+ unsigned long *data; /* bitmap representing pages */
};
+static inline unsigned long bm_block_bits(struct bm_block *bb)
+{
+ 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 */
struct bm_position {
struct zone_bitmap *zone_bm;
struct bm_block *block;
- int chunk;
int bit;
};
/* Functions that operate on memory bitmaps */
-static inline void memory_bm_reset_chunk(struct memory_bitmap *bm)
-{
- bm->cur.chunk = 0;
- bm->cur.bit = -1;
-}
-
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;
- memory_bm_reset_chunk(bm);
+ bm->cur.bit = 0;
}
static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free);
bb->start_pfn = pfn;
if (nr >= BM_BITS_PER_BLOCK) {
pfn += BM_BITS_PER_BLOCK;
- bb->size = BM_CHUNKS_PER_BLOCK;
nr -= BM_BITS_PER_BLOCK;
} else {
/* This is executed only once in the loop */
pfn += nr;
- bb->size = DIV_ROUND_UP(nr, BM_BITS_PER_CHUNK);
}
bb->end_pfn = pfn;
bb = bb->next;
* of @bm->cur_zone_bm are updated.
*/
-static void memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
+static int memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
void **addr, unsigned int *bit_nr)
{
struct zone_bitmap *zone_bm;
while (pfn < zone_bm->start_pfn || pfn >= zone_bm->end_pfn) {
zone_bm = zone_bm->next;
- BUG_ON(!zone_bm);
+ if (!zone_bm)
+ return -EFAULT;
}
bm->cur.zone_bm = zone_bm;
}
}
zone_bm->cur_block = bb;
pfn -= bb->start_pfn;
- *bit_nr = pfn % BM_BITS_PER_CHUNK;
- *addr = bb->data + pfn / BM_BITS_PER_CHUNK;
+ *bit_nr = pfn;
+ *addr = bb->data;
+ return 0;
}
static void memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn)
{
void *addr;
unsigned int bit;
+ int error;
- memory_bm_find_bit(bm, pfn, &addr, &bit);
+ error = memory_bm_find_bit(bm, pfn, &addr, &bit);
+ BUG_ON(error);
set_bit(bit, addr);
}
-static void memory_bm_clear_bit(struct memory_bitmap *bm, unsigned long pfn)
+static int mem_bm_set_bit_check(struct memory_bitmap *bm, unsigned long pfn)
{
void *addr;
unsigned int bit;
+ int error;
- memory_bm_find_bit(bm, pfn, &addr, &bit);
- clear_bit(bit, addr);
+ error = memory_bm_find_bit(bm, pfn, &addr, &bit);
+ if (!error)
+ set_bit(bit, addr);
+ return error;
}
-static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn)
+static void memory_bm_clear_bit(struct memory_bitmap *bm, unsigned long pfn)
{
void *addr;
unsigned int bit;
+ int error;
- memory_bm_find_bit(bm, pfn, &addr, &bit);
- return test_bit(bit, addr);
-}
-
-/* Two auxiliary functions for memory_bm_next_pfn */
-
-/* Find the first set bit in the given chunk, if there is one */
-
-static inline int next_bit_in_chunk(int bit, unsigned long *chunk_p)
-{
- bit++;
- while (bit < BM_BITS_PER_CHUNK) {
- if (test_bit(bit, chunk_p))
- return bit;
-
- bit++;
- }
- return -1;
+ error = memory_bm_find_bit(bm, pfn, &addr, &bit);
+ BUG_ON(error);
+ clear_bit(bit, addr);
}
-/* Find a chunk containing some bits set in given block of bits */
-
-static inline int next_chunk_in_block(int n, struct bm_block *bb)
+static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn)
{
- n++;
- while (n < bb->size) {
- if (bb->data[n])
- return n;
+ void *addr;
+ unsigned int bit;
+ int error;
- n++;
- }
- return -1;
+ error = memory_bm_find_bit(bm, pfn, &addr, &bit);
+ BUG_ON(error);
+ return test_bit(bit, addr);
}
/**
{
struct zone_bitmap *zone_bm;
struct bm_block *bb;
- int chunk;
int bit;
do {
bb = bm->cur.block;
do {
- chunk = bm->cur.chunk;
bit = bm->cur.bit;
- do {
- bit = next_bit_in_chunk(bit, bb->data + chunk);
- if (bit >= 0)
- goto Return_pfn;
-
- chunk = next_chunk_in_block(chunk, bb);
- bit = -1;
- } while (chunk >= 0);
+ 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;
- memory_bm_reset_chunk(bm);
+ 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;
- memory_bm_reset_chunk(bm);
+ bm->cur.bit = 0;
}
} while (zone_bm);
memory_bm_position_reset(bm);
return BM_END_OF_MAP;
Return_pfn:
- bm->cur.chunk = chunk;
- bm->cur.bit = bit;
- return bb->start_pfn + chunk * BM_BITS_PER_CHUNK + bit;
+ bm->cur.bit = bit + 1;
+ return bb->start_pfn + bit;
}
/**
region->end_pfn << PAGE_SHIFT);
for (pfn = region->start_pfn; pfn < region->end_pfn; pfn++)
- if (pfn_valid(pfn))
- memory_bm_set_bit(bm, pfn);
+ if (pfn_valid(pfn)) {
+ /*
+ * It is safe to ignore the result of
+ * mem_bm_set_bit_check() here, since we won't
+ * touch the PFNs for which the error is
+ * returned anyway.
+ */
+ mem_bm_set_bit_check(bm, pfn);
+ }
}
}
#endif /* CONFIG_HIGHMEM */
/**
- * saveable - Determine whether a non-highmem page should be included in
- * the suspend image.
+ * saveable_page - Determine whether a non-highmem page should be included
+ * in the suspend image.
*
* We should save the page if it isn't Nosave, and is not in the range
* of pages statically defined as 'unsaveable', and it isn't a part of
if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page))
return NULL;
- if (PageReserved(page) && pfn_is_nosave(pfn))
+ if (PageReserved(page)
+ && (!kernel_page_present(page) || pfn_is_nosave(pfn)))
return NULL;
return page;
*dst++ = *src++;
}
+
+/**
+ * safe_copy_page - check if the page we are going to copy is marked as
+ * present in the kernel page tables (this always is the case if
+ * CONFIG_DEBUG_PAGEALLOC is not set and in that case
+ * kernel_page_present() always returns 'true').
+ */
+static void safe_copy_page(void *dst, struct page *s_page)
+{
+ if (kernel_page_present(s_page)) {
+ do_copy_page(dst, page_address(s_page));
+ } else {
+ kernel_map_pages(s_page, 1, 1);
+ do_copy_page(dst, page_address(s_page));
+ kernel_map_pages(s_page, 1, 0);
+ }
+}
+
+
#ifdef CONFIG_HIGHMEM
static inline struct page *
page_is_saveable(struct zone *zone, unsigned long pfn)
saveable_highmem_page(pfn) : saveable_page(pfn);
}
-static inline void
-copy_data_page(unsigned long dst_pfn, unsigned long src_pfn)
+static void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn)
{
struct page *s_page, *d_page;
void *src, *dst;
kunmap_atomic(src, KM_USER0);
kunmap_atomic(dst, KM_USER1);
} else {
- src = page_address(s_page);
if (PageHighMem(d_page)) {
/* Page pointed to by src may contain some kernel
* data modified by kmap_atomic()
*/
- do_copy_page(buffer, src);
+ safe_copy_page(buffer, s_page);
dst = kmap_atomic(pfn_to_page(dst_pfn), KM_USER0);
memcpy(dst, buffer, PAGE_SIZE);
kunmap_atomic(dst, KM_USER0);
} else {
- dst = page_address(d_page);
- do_copy_page(dst, src);
+ safe_copy_page(page_address(d_page), s_page);
}
}
}
#else
#define page_is_saveable(zone, pfn) saveable_page(pfn)
-static inline void
-copy_data_page(unsigned long dst_pfn, unsigned long src_pfn)
+static inline void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn)
{
- do_copy_page(page_address(pfn_to_page(dst_pfn)),
- page_address(pfn_to_page(src_pfn)));
+ safe_copy_page(page_address(pfn_to_page(dst_pfn)),
+ pfn_to_page(src_pfn));
}
#endif /* CONFIG_HIGHMEM */
projects / linux-2.6-omap-h63xx.git / blobdiff