mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-25 05:34:00 +08:00
d1310b2e0c
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>
56 lines
1.3 KiB
C
56 lines
1.3 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
|
|
|
|
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
|