linux/fs/btrfs/extent_io.h
Chris Mason 065631f6dc Btrfs: checksum file data at bio submission time instead of during writepage
When we checkum file data during writepage, the checksumming is done one
page at a time, making it difficult to do bulk metadata modifications
to insert checksums for large ranges of the file at once.

This patch changes btrfs to checksum on a per-bio basis instead.  The
bios are checksummed before they are handed off to the block layer, so
each bio is contiguous and only has pages from the same inode.

Checksumming on a bio basis allows us to insert and modify the file
checksum items in large groups.  It also allows the checksumming to
be done more easily by async worker threads.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:00 -04:00

216 lines
7.7 KiB
C

#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_state;
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 (*submit_bio_hook)(int rw, struct bio *bio);
int (*readpage_io_hook)(struct page *page, u64 start, u64 end);
int (*readpage_end_io_hook)(struct page *page, u64 start, u64 end,
struct extent_state *state);
void (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
struct extent_state *state);
int (*set_bit_hook)(struct inode *inode, u64 start, u64 end,
unsigned long old, unsigned long bits);
int (*clear_bit_hook)(struct inode *inode, u64 start, u64 end,
unsigned long old, unsigned long bits);
};
struct extent_io_tree {
struct rb_root state;
struct address_space *mapping;
u64 dirty_bytes;
spinlock_t lock;
struct extent_io_ops *ops;
spinlock_t lru_lock;
struct list_head buffer_lru;
int lru_size;
struct extent_state *last;
};
struct extent_state {
u64 start;
u64 end; /* inclusive */
struct rb_node rb_node;
struct extent_io_tree *tree;
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;
static inline struct extent_state *extent_state_next(struct extent_state *state)
{
struct rb_node *node;
node = rb_next(&state->rb_node);
if (!node)
return NULL;
return rb_entry(node, struct extent_state, rb_node);
}
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,
gfp_t mask);
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);
struct extent_state *find_first_extent_bit_state(struct extent_io_tree *tree,
u64 start, 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,
get_extent_t *get_extent);
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