diff options
Diffstat (limited to 'fs/btrfs/extent_io.h')
-rw-r--r-- | fs/btrfs/extent_io.h | 26 |
1 files changed, 24 insertions, 2 deletions
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h index 28cd88fccc7e..ab31d145227e 100644 --- a/fs/btrfs/extent_io.h +++ b/fs/btrfs/extent_io.h @@ -59,6 +59,28 @@ */ #define EXTENT_PAGE_PRIVATE 1 +/* + * The extent buffer bitmap operations are done with byte granularity instead of + * word granularity for two reasons: + * 1. The bitmaps must be little-endian on disk. + * 2. Bitmap items are not guaranteed to be aligned to a word and therefore a + * single word in a bitmap may straddle two pages in the extent buffer. + */ +#define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE) +#define BYTE_MASK ((1 << BITS_PER_BYTE) - 1) +#define BITMAP_FIRST_BYTE_MASK(start) \ + ((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK) +#define BITMAP_LAST_BYTE_MASK(nbits) \ + (BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1))) + +static inline int le_test_bit(int nr, const u8 *addr) +{ + return 1U & (addr[BIT_BYTE(nr)] >> (nr & (BITS_PER_BYTE-1))); +} + +extern void le_bitmap_set(u8 *map, unsigned int start, int len); +extern void le_bitmap_clear(u8 *map, unsigned int start, int len); + struct extent_state; struct btrfs_root; struct btrfs_io_bio; @@ -359,7 +381,7 @@ void free_extent_buffer_stale(struct extent_buffer *eb); #define WAIT_COMPLETE 1 #define WAIT_PAGE_LOCK 2 int read_extent_buffer_pages(struct extent_io_tree *tree, - struct extent_buffer *eb, u64 start, int wait, + struct extent_buffer *eb, int wait, get_extent_t *get_extent, int mirror_num); void wait_on_extent_buffer_writeback(struct extent_buffer *eb); @@ -413,7 +435,7 @@ int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset, void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end); void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end); void extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end, - struct page *locked_page, + u64 delalloc_end, struct page *locked_page, unsigned bits_to_clear, unsigned long page_ops); struct bio * |