linux/fs/btrfs/extent_map.h
Chris Mason 3ab2fb5a8c Btrfs: Add readpages support
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:57 -04:00

213 lines
7.6 KiB
C

#ifndef __EXTENTMAP__
#define __EXTENTMAP__
#include <linux/rbtree.h>
#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;
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 */
u64 block_start;
u64 block_end; /* inclusive */
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;
};
typedef struct extent_map *(get_extent_t)(struct inode *inode,
struct page *page,
size_t page_offset,
u64 start, u64 end,
int create);
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);
struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
u64 start, u64 end);
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);
void __init extent_map_init(void);
void __exit extent_map_exit(void);
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