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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef BTRFS_EXTENT_MAP_H
#define BTRFS_EXTENT_MAP_H
#include <linux/rbtree.h>
#include <linux/refcount.h>
#define EXTENT_MAP_LAST_BYTE ((u64)-4)
#define EXTENT_MAP_HOLE ((u64)-3)
#define EXTENT_MAP_INLINE ((u64)-2)
/* used only during fiemap calls */
#define EXTENT_MAP_DELALLOC ((u64)-1)
/* bits for the extent_map::flags field */
enum {
/* this entry not yet on disk, don't free it */
EXTENT_FLAG_PINNED,
EXTENT_FLAG_COMPRESSED,
/* pre-allocated extent */
EXTENT_FLAG_PREALLOC,
/* Logging this extent */
EXTENT_FLAG_LOGGING,
/* Filling in a preallocated extent */
EXTENT_FLAG_FILLING,
/* filesystem extent mapping type */
EXTENT_FLAG_FS_MAPPING,
/* This em is merged from two or more physically adjacent ems */
EXTENT_FLAG_MERGED,
};
struct extent_map {
struct rb_node rb_node;
/* all of these are in bytes */
u64 start;
u64 len;
u64 mod_start;
u64 mod_len;
u64 orig_start;
u64 orig_block_len;
u64 ram_bytes;
u64 block_start;
u64 block_len;
/*
* Generation of the extent map, for merged em it's the highest
* generation of all merged ems.
* For non-merged extents, it's from btrfs_file_extent_item::generation.
*/
u64 generation;
unsigned long flags;
/* Used for chunk mappings, flag EXTENT_FLAG_FS_MAPPING must be set */
struct map_lookup *map_lookup;
refcount_t refs;
unsigned int compress_type;
struct list_head list;
};
struct extent_map_tree {
struct rb_root_cached map;
struct list_head modified_extents;
rwlock_t lock;
};
static inline int extent_map_in_tree(const struct extent_map *em)
{
return !RB_EMPTY_NODE(&em->rb_node);
}
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->block_len < em->block_start)
return (u64)-1;
return em->block_start + em->block_len;
}
void extent_map_tree_init(struct extent_map_tree *tree);
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 modified);
void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
void replace_extent_mapping(struct extent_map_tree *tree,
struct extent_map *cur,
struct extent_map *new,
int modified);
struct extent_map *alloc_extent_map(void);
void free_extent_map(struct extent_map *em);
int __init extent_map_init(void);
void __cold extent_map_exit(void);
int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen);
void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em);
struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
u64 start, u64 len);
int btrfs_add_extent_mapping(struct btrfs_fs_info *fs_info,
struct extent_map_tree *em_tree,
struct extent_map **em_in, u64 start, u64 len);
#endif
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