linux/fs/btrfs/extent_map.h
Chris Mason 7f3c74fb83 Btrfs: Keep extent mappings in ram until pending ordered extents are done
It was possible for stale mappings from disk to be used instead of the
new pending ordered extent.  This adds a flag to the extent map struct
to keep it pinned until the pending ordered extent is actually on disk.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:05 -04:00

58 lines
1.4 KiB
C

#ifndef __EXTENTMAP__
#define __EXTENTMAP__
#include <linux/rbtree.h>
#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 flags field */
#define EXTENT_FLAG_PINNED 0 /* this entry not yet on disk, don't free it */
struct extent_map {
struct rb_node rb_node;
/* all of these are in bytes */
u64 start;
u64 len;
u64 block_start;
unsigned long flags;
struct block_device *bdev;
atomic_t refs;
int in_tree;
};
struct extent_map_tree {
struct rb_root map;
struct extent_map *last;
spinlock_t lock;
};
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, gfp_t mask);
struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
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);
struct extent_map *alloc_extent_map(gfp_t mask);
void free_extent_map(struct extent_map *em);
int __init extent_map_init(void);
void extent_map_exit(void);
#endif