1/* SPDX-License-Identifier: GPL-2.0 */
2
3#ifndef BTRFS_BLOCK_RSV_H
4#define BTRFS_BLOCK_RSV_H
5
6#include <linux/types.h>
7#include <linux/compiler.h>
8#include <linux/spinlock.h>
9
10struct btrfs_trans_handle;
11struct btrfs_root;
12struct btrfs_space_info;
13struct btrfs_block_rsv;
14struct btrfs_fs_info;
15enum btrfs_reserve_flush_enum;
16
17/*
18 * Types of block reserves
19 */
20enum btrfs_rsv_type {
21 BTRFS_BLOCK_RSV_GLOBAL,
22 BTRFS_BLOCK_RSV_DELALLOC,
23 BTRFS_BLOCK_RSV_TRANS,
24 BTRFS_BLOCK_RSV_CHUNK,
25 BTRFS_BLOCK_RSV_DELOPS,
26 BTRFS_BLOCK_RSV_DELREFS,
27 BTRFS_BLOCK_RSV_TREELOG,
28 BTRFS_BLOCK_RSV_EMPTY,
29 BTRFS_BLOCK_RSV_TEMP,
30};
31
32struct btrfs_block_rsv {
33 u64 size;
34 u64 reserved;
35 struct btrfs_space_info *space_info;
36 spinlock_t lock;
37 bool full;
38 bool failfast;
39 /* Block reserve type, one of BTRFS_BLOCK_RSV_* */
40 enum btrfs_rsv_type type:8;
41
42 /*
43 * Qgroup equivalent for @size @reserved
44 *
45 * Unlike normal @size/@reserved for inode rsv, qgroup doesn't care
46 * about things like csum size nor how many tree blocks it will need to
47 * reserve.
48 *
49 * Qgroup cares more about net change of the extent usage.
50 *
51 * So for one newly inserted file extent, in worst case it will cause
52 * leaf split and level increase, nodesize for each file extent is
53 * already too much.
54 *
55 * In short, qgroup_size/reserved is the upper limit of possible needed
56 * qgroup metadata reservation.
57 */
58 u64 qgroup_rsv_size;
59 u64 qgroup_rsv_reserved;
60};
61
62void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv, enum btrfs_rsv_type type);
63void btrfs_init_root_block_rsv(struct btrfs_root *root);
64struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_fs_info *fs_info,
65 enum btrfs_rsv_type type);
66void btrfs_init_metadata_block_rsv(struct btrfs_fs_info *fs_info,
67 struct btrfs_block_rsv *rsv,
68 enum btrfs_rsv_type type);
69void btrfs_free_block_rsv(struct btrfs_fs_info *fs_info,
70 struct btrfs_block_rsv *rsv);
71int btrfs_block_rsv_add(struct btrfs_fs_info *fs_info,
72 struct btrfs_block_rsv *block_rsv, u64 num_bytes,
73 enum btrfs_reserve_flush_enum flush);
74int btrfs_block_rsv_check(struct btrfs_block_rsv *block_rsv, int min_percent);
75int btrfs_block_rsv_refill(struct btrfs_fs_info *fs_info,
76 struct btrfs_block_rsv *block_rsv, u64 num_bytes,
77 enum btrfs_reserve_flush_enum flush);
78int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
79 struct btrfs_block_rsv *dst_rsv, u64 num_bytes,
80 bool update_size);
81int btrfs_block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv, u64 num_bytes);
82void btrfs_block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
83 u64 num_bytes, bool update_size);
84u64 btrfs_block_rsv_release(struct btrfs_fs_info *fs_info,
85 struct btrfs_block_rsv *block_rsv,
86 u64 num_bytes, u64 *qgroup_to_release);
87void btrfs_update_global_block_rsv(struct btrfs_fs_info *fs_info);
88void btrfs_init_global_block_rsv(struct btrfs_fs_info *fs_info);
89void btrfs_release_global_block_rsv(struct btrfs_fs_info *fs_info);
90struct btrfs_block_rsv *btrfs_use_block_rsv(struct btrfs_trans_handle *trans,
91 struct btrfs_root *root,
92 u32 blocksize);
93int btrfs_check_trunc_cache_free_space(const struct btrfs_fs_info *fs_info,
94 struct btrfs_block_rsv *rsv);
95static inline void btrfs_unuse_block_rsv(struct btrfs_fs_info *fs_info,
96 struct btrfs_block_rsv *block_rsv,
97 u32 blocksize)
98{
99 btrfs_block_rsv_add_bytes(block_rsv, num_bytes: blocksize, update_size: false);
100 btrfs_block_rsv_release(fs_info, block_rsv, num_bytes: 0, NULL);
101}
102
103/*
104 * Fast path to check if the reserve is full, may be carefully used outside of
105 * locks.
106 */
107static inline bool btrfs_block_rsv_full(const struct btrfs_block_rsv *rsv)
108{
109 return data_race(rsv->full);
110}
111
112/*
113 * Get the reserved mount of a block reserve in a context where getting a stale
114 * value is acceptable, instead of accessing it directly and trigger data race
115 * warning from KCSAN.
116 */
117static inline u64 btrfs_block_rsv_reserved(struct btrfs_block_rsv *rsv)
118{
119 u64 ret;
120
121 spin_lock(lock: &rsv->lock);
122 ret = rsv->reserved;
123 spin_unlock(lock: &rsv->lock);
124
125 return ret;
126}
127
128/*
129 * Get the size of a block reserve in a context where getting a stale value is
130 * acceptable, instead of accessing it directly and trigger data race warning
131 * from KCSAN.
132 */
133static inline u64 btrfs_block_rsv_size(struct btrfs_block_rsv *rsv)
134{
135 u64 ret;
136
137 spin_lock(lock: &rsv->lock);
138 ret = rsv->size;
139 spin_unlock(lock: &rsv->lock);
140
141 return ret;
142}
143
144#endif /* BTRFS_BLOCK_RSV_H */
145

source code of linux/fs/btrfs/block-rsv.h