From d1310b2e0cd98eb1348553e69b73827b436dca7b Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Thu, 24 Jan 2008 16:13:08 -0500 Subject: Btrfs: Split the extent_map code into two parts There is now extent_map for mapping offsets in the file to disk and extent_io for state tracking, IO submission and extent_bufers. The new extent_map code shifts from [start,end] pairs to [start,len], and pushes the locking out into the caller. This allows a few performance optimizations and is easier to use. A number of extent_map usage bugs were fixed, mostly with failing to remove extent_map entries when changing the file. Signed-off-by: Chris Mason --- fs/btrfs/extent_map.h | 214 ++++++-------------------------------------------- 1 file changed, 26 insertions(+), 188 deletions(-) (limited to 'fs/btrfs/extent_map.h') diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h index ea60f5447b5..56314217cfc 100644 --- a/fs/btrfs/extent_map.h +++ b/fs/btrfs/extent_map.h @@ -3,215 +3,53 @@ #include +#define EXTENT_MAP_LAST_BYTE (u64)-4 #define EXTENT_MAP_HOLE (u64)-3 #define EXTENT_MAP_INLINE (u64)-2 #define EXTENT_MAP_DELALLOC (u64)-1 -/* bits for the extent state */ -#define EXTENT_DIRTY 1 -#define EXTENT_WRITEBACK (1 << 1) -#define EXTENT_UPTODATE (1 << 2) -#define EXTENT_LOCKED (1 << 3) -#define EXTENT_NEW (1 << 4) -#define EXTENT_DELALLOC (1 << 5) -#define EXTENT_DEFRAG (1 << 6) -#define EXTENT_DEFRAG_DONE (1 << 7) -#define EXTENT_BUFFER_FILLED (1 << 8) -#define EXTENT_CSUM (1 << 9) -#define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK) - -/* - * page->private values. Every page that is controlled by the extent - * map has page->private set to one. - */ -#define EXTENT_PAGE_PRIVATE 1 -#define EXTENT_PAGE_PRIVATE_FIRST_PAGE 3 - - -struct extent_map_ops { - int (*fill_delalloc)(struct inode *inode, u64 start, u64 end); - int (*writepage_io_hook)(struct page *page, u64 start, u64 end); - int (*readpage_io_hook)(struct page *page, u64 start, u64 end); - int (*readpage_end_io_hook)(struct page *page, u64 start, u64 end); - void (*writepage_end_io_hook)(struct page *page, u64 start, u64 end); -}; - -struct extent_map_tree { - struct rb_root map; - struct rb_root state; - struct address_space *mapping; - u64 dirty_bytes; - rwlock_t lock; - struct extent_map_ops *ops; - spinlock_t lru_lock; - struct list_head buffer_lru; - int lru_size; -}; - -/* note, this must start with the same fields as fs/extent_map.c:tree_entry */ struct extent_map { - u64 start; - u64 end; /* inclusive */ - int in_tree; struct rb_node rb_node; - /* block_start and block_end are in bytes */ + + /* all of these are in bytes */ + u64 start; + u64 len; u64 block_start; - u64 block_end; /* inclusive */ + unsigned long flags; struct block_device *bdev; atomic_t refs; -}; - -/* note, this must start with the same fields as fs/extent_map.c:tree_entry */ -struct extent_state { - u64 start; - u64 end; /* inclusive */ int in_tree; - struct rb_node rb_node; - wait_queue_head_t wq; - atomic_t refs; - unsigned long state; - - /* for use by the FS */ - u64 private; - - struct list_head list; }; -struct extent_buffer { - u64 start; - unsigned long len; - char *map_token; - char *kaddr; - unsigned long map_start; - unsigned long map_len; - struct page *first_page; - struct list_head lru; - atomic_t refs; - int flags; +struct extent_map_tree { + struct rb_root map; + struct extent_map *last; + spinlock_t lock; }; -typedef struct extent_map *(get_extent_t)(struct inode *inode, - struct page *page, - size_t page_offset, - u64 start, u64 end, - int create); +static inline u64 extent_map_end(struct extent_map *em) +{ + if (em->start + em->len < em->start) + return (u64)-1; + return em->start + em->len; +} + +static inline u64 extent_map_block_end(struct extent_map *em) +{ + if (em->block_start + em->len < em->block_start) + return (u64)-1; + return em->block_start + em->len; +} -void extent_map_tree_init(struct extent_map_tree *tree, - struct address_space *mapping, gfp_t mask); -void extent_map_tree_empty_lru(struct extent_map_tree *tree); +void extent_map_tree_init(struct extent_map_tree *tree, gfp_t mask); struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, - u64 start, u64 end); + u64 start, u64 len); int add_extent_mapping(struct extent_map_tree *tree, struct extent_map *em); int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em); -int try_release_extent_mapping(struct extent_map_tree *tree, struct page *page); -int lock_extent(struct extent_map_tree *tree, u64 start, u64 end, gfp_t mask); -int unlock_extent(struct extent_map_tree *tree, u64 start, u64 end, gfp_t mask); + struct extent_map *alloc_extent_map(gfp_t mask); void free_extent_map(struct extent_map *em); -int extent_read_full_page(struct extent_map_tree *tree, struct page *page, - get_extent_t *get_extent); int __init extent_map_init(void); void extent_map_exit(void); - -u64 count_range_bits(struct extent_map_tree *tree, - u64 *start, u64 search_end, - u64 max_bytes, unsigned long bits); - -int test_range_bit(struct extent_map_tree *tree, u64 start, u64 end, - int bits, int filled); -int clear_extent_bits(struct extent_map_tree *tree, u64 start, u64 end, - int bits, gfp_t mask); -int set_extent_bits(struct extent_map_tree *tree, u64 start, u64 end, - int bits, gfp_t mask); -int set_extent_uptodate(struct extent_map_tree *tree, u64 start, u64 end, - gfp_t mask); -int set_extent_new(struct extent_map_tree *tree, u64 start, u64 end, - gfp_t mask); -int set_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end, - gfp_t mask); -int clear_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end, - gfp_t mask); -int set_extent_delalloc(struct extent_map_tree *tree, u64 start, u64 end, - gfp_t mask); -int find_first_extent_bit(struct extent_map_tree *tree, u64 start, - u64 *start_ret, u64 *end_ret, int bits); -int extent_invalidatepage(struct extent_map_tree *tree, - struct page *page, unsigned long offset); -int extent_write_full_page(struct extent_map_tree *tree, struct page *page, - get_extent_t *get_extent, - struct writeback_control *wbc); -int extent_writepages(struct extent_map_tree *tree, - struct address_space *mapping, - get_extent_t *get_extent, - struct writeback_control *wbc); -int extent_readpages(struct extent_map_tree *tree, - struct address_space *mapping, - struct list_head *pages, unsigned nr_pages, - get_extent_t get_extent); -int extent_prepare_write(struct extent_map_tree *tree, - struct inode *inode, struct page *page, - unsigned from, unsigned to, get_extent_t *get_extent); -int extent_commit_write(struct extent_map_tree *tree, - struct inode *inode, struct page *page, - unsigned from, unsigned to); -sector_t extent_bmap(struct address_space *mapping, sector_t iblock, - get_extent_t *get_extent); -int set_range_dirty(struct extent_map_tree *tree, u64 start, u64 end); -int set_state_private(struct extent_map_tree *tree, u64 start, u64 private); -int get_state_private(struct extent_map_tree *tree, u64 start, u64 *private); -void set_page_extent_mapped(struct page *page); - -struct extent_buffer *alloc_extent_buffer(struct extent_map_tree *tree, - u64 start, unsigned long len, - struct page *page0, - gfp_t mask); -struct extent_buffer *find_extent_buffer(struct extent_map_tree *tree, - u64 start, unsigned long len, - gfp_t mask); -void free_extent_buffer(struct extent_buffer *eb); -int read_extent_buffer_pages(struct extent_map_tree *tree, - struct extent_buffer *eb, u64 start, int wait); - -static inline void extent_buffer_get(struct extent_buffer *eb) -{ - atomic_inc(&eb->refs); -} - -int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv, - unsigned long start, - unsigned long len); -void read_extent_buffer(struct extent_buffer *eb, void *dst, - unsigned long start, - unsigned long len); -void write_extent_buffer(struct extent_buffer *eb, const void *src, - unsigned long start, unsigned long len); -void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, - unsigned long dst_offset, unsigned long src_offset, - unsigned long len); -void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, - unsigned long src_offset, unsigned long len); -void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, - unsigned long src_offset, unsigned long len); -void memset_extent_buffer(struct extent_buffer *eb, char c, - unsigned long start, unsigned long len); -int wait_on_extent_buffer_writeback(struct extent_map_tree *tree, - struct extent_buffer *eb); -int clear_extent_buffer_dirty(struct extent_map_tree *tree, - struct extent_buffer *eb); -int set_extent_buffer_dirty(struct extent_map_tree *tree, - struct extent_buffer *eb); -int set_extent_buffer_uptodate(struct extent_map_tree *tree, - struct extent_buffer *eb); -int extent_buffer_uptodate(struct extent_map_tree *tree, - struct extent_buffer *eb); -int map_extent_buffer(struct extent_buffer *eb, unsigned long offset, - unsigned long min_len, char **token, char **map, - unsigned long *map_start, - unsigned long *map_len, int km); -int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset, - unsigned long min_len, char **token, char **map, - unsigned long *map_start, - unsigned long *map_len, int km); -void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km); #endif -- cgit v1.2.3-18-g5258