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_io.h | 193 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 193 insertions(+) create mode 100644 fs/btrfs/extent_io.h (limited to 'fs/btrfs/extent_io.h') diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h new file mode 100644 index 00000000000..06be1fe84b2 --- /dev/null +++ b/fs/btrfs/extent_io.h @@ -0,0 +1,193 @@ +#ifndef __EXTENTIO__ +#define __EXTENTIO__ + +#include + +/* 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_io_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_io_tree { + struct rb_root state; + struct address_space *mapping; + u64 dirty_bytes; + rwlock_t lock; + struct extent_io_ops *ops; + spinlock_t lru_lock; + struct list_head buffer_lru; + int lru_size; +}; + +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; + +typedef struct extent_map *(get_extent_t)(struct inode *inode, + struct page *page, + size_t page_offset, + u64 start, u64 len, + int create); + +void extent_io_tree_init(struct extent_io_tree *tree, + struct address_space *mapping, gfp_t mask); +void extent_io_tree_empty_lru(struct extent_io_tree *tree); +int try_release_extent_mapping(struct extent_map_tree *map, + struct extent_io_tree *tree, struct page *page); +int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask); +int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask); +int extent_read_full_page(struct extent_io_tree *tree, struct page *page, + get_extent_t *get_extent); +int __init extent_io_init(void); +void extent_io_exit(void); + +u64 count_range_bits(struct extent_io_tree *tree, + u64 *start, u64 search_end, + u64 max_bytes, unsigned long bits); + +int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end, + int bits, int filled); +int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, + int bits, gfp_t mask); +int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, + int bits, gfp_t mask); +int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end, + gfp_t mask); +int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end, + gfp_t mask); +int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, + gfp_t mask); +int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, + gfp_t mask); +int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end, + gfp_t mask); +int find_first_extent_bit(struct extent_io_tree *tree, u64 start, + u64 *start_ret, u64 *end_ret, int bits); +int extent_invalidatepage(struct extent_io_tree *tree, + struct page *page, unsigned long offset); +int extent_write_full_page(struct extent_io_tree *tree, struct page *page, + get_extent_t *get_extent, + struct writeback_control *wbc); +int extent_writepages(struct extent_io_tree *tree, + struct address_space *mapping, + get_extent_t *get_extent, + struct writeback_control *wbc); +int extent_readpages(struct extent_io_tree *tree, + struct address_space *mapping, + struct list_head *pages, unsigned nr_pages, + get_extent_t get_extent); +int extent_prepare_write(struct extent_io_tree *tree, + struct inode *inode, struct page *page, + unsigned from, unsigned to, get_extent_t *get_extent); +int extent_commit_write(struct extent_io_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_io_tree *tree, u64 start, u64 end); +int set_state_private(struct extent_io_tree *tree, u64 start, u64 private); +int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private); +void set_page_extent_mapped(struct page *page); + +struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree, + u64 start, unsigned long len, + struct page *page0, + gfp_t mask); +struct extent_buffer *find_extent_buffer(struct extent_io_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_io_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_io_tree *tree, + struct extent_buffer *eb); +int clear_extent_buffer_dirty(struct extent_io_tree *tree, + struct extent_buffer *eb); +int set_extent_buffer_dirty(struct extent_io_tree *tree, + struct extent_buffer *eb); +int set_extent_buffer_uptodate(struct extent_io_tree *tree, + struct extent_buffer *eb); +int extent_buffer_uptodate(struct extent_io_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 v1.2.3-70-g09d2