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 <chris.mason@oracle.com>
This commit is contained in:
Chris Mason
193
fs/btrfs/extent_io.h
Normal file
193
fs/btrfs/extent_io.h
Normal file
@@ -0,0 +1,193 @@
|
||||
#ifndef __EXTENTIO__
|
||||
#define __EXTENTIO__
|
||||
|
||||
#include <linux/rbtree.h>
|
||||
|
||||
/* 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
|
||||
Reference in New Issue
Block a user