1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (C) 2009 Oracle. All rights reserved.
4 */
5
6#ifndef BTRFS_FREE_SPACE_CACHE_H
7#define BTRFS_FREE_SPACE_CACHE_H
8
9#include <linux/rbtree.h>
10#include <linux/list.h>
11#include <linux/spinlock.h>
12#include <linux/mutex.h>
13#include <linux/freezer.h>
14#include "fs.h"
15
16struct inode;
17struct page;
18struct btrfs_fs_info;
19struct btrfs_path;
20struct btrfs_trans_handle;
21struct btrfs_trim_block_group;
22
23/*
24 * This is the trim state of an extent or bitmap.
25 *
26 * BTRFS_TRIM_STATE_TRIMMING is special and used to maintain the state of a
27 * bitmap as we may need several trims to fully trim a single bitmap entry.
28 * This is reset should any free space other than trimmed space be added to the
29 * bitmap.
30 */
31enum btrfs_trim_state {
32 BTRFS_TRIM_STATE_UNTRIMMED,
33 BTRFS_TRIM_STATE_TRIMMED,
34 BTRFS_TRIM_STATE_TRIMMING,
35};
36
37struct btrfs_free_space {
38 struct rb_node offset_index;
39 struct rb_node bytes_index;
40 u64 offset;
41 u64 bytes;
42 u64 max_extent_size;
43 unsigned long *bitmap;
44 struct list_head list;
45 enum btrfs_trim_state trim_state;
46 s32 bitmap_extents;
47};
48
49static inline bool btrfs_free_space_trimmed(struct btrfs_free_space *info)
50{
51 return (info->trim_state == BTRFS_TRIM_STATE_TRIMMED);
52}
53
54static inline bool btrfs_free_space_trimming_bitmap(
55 struct btrfs_free_space *info)
56{
57 return (info->trim_state == BTRFS_TRIM_STATE_TRIMMING);
58}
59
60static inline bool btrfs_trim_interrupted(void)
61{
62 return fatal_signal_pending(current) || freezing(current);
63}
64
65/*
66 * Deltas are an effective way to populate global statistics. Give macro names
67 * to make it clear what we're doing. An example is discard_extents in
68 * btrfs_free_space_ctl.
69 */
70enum {
71 BTRFS_STAT_CURR,
72 BTRFS_STAT_PREV,
73 BTRFS_STAT_NR_ENTRIES,
74};
75
76struct btrfs_free_space_ctl {
77 spinlock_t tree_lock;
78 struct rb_root free_space_offset;
79 struct rb_root_cached free_space_bytes;
80 u64 free_space;
81 int extents_thresh;
82 int free_extents;
83 int total_bitmaps;
84 int unit;
85 u64 start;
86 s32 discardable_extents[BTRFS_STAT_NR_ENTRIES];
87 s64 discardable_bytes[BTRFS_STAT_NR_ENTRIES];
88 const struct btrfs_free_space_op *op;
89 struct btrfs_block_group *block_group;
90 struct mutex cache_writeout_mutex;
91 struct list_head trimming_ranges;
92};
93
94struct btrfs_free_space_op {
95 bool (*use_bitmap)(struct btrfs_free_space_ctl *ctl,
96 struct btrfs_free_space *info);
97};
98
99struct btrfs_io_ctl {
100 void *cur, *orig;
101 struct page *page;
102 struct page **pages;
103 struct btrfs_fs_info *fs_info;
104 struct inode *inode;
105 unsigned long size;
106 int index;
107 int num_pages;
108 int entries;
109 int bitmaps;
110};
111
112int __init btrfs_free_space_init(void);
113void __cold btrfs_free_space_exit(void);
114struct inode *lookup_free_space_inode(struct btrfs_block_group *block_group,
115 struct btrfs_path *path);
116int create_free_space_inode(struct btrfs_trans_handle *trans,
117 struct btrfs_block_group *block_group,
118 struct btrfs_path *path);
119int btrfs_remove_free_space_inode(struct btrfs_trans_handle *trans,
120 struct inode *inode,
121 struct btrfs_block_group *block_group);
122
123int btrfs_truncate_free_space_cache(struct btrfs_trans_handle *trans,
124 struct btrfs_block_group *block_group,
125 struct inode *inode);
126int load_free_space_cache(struct btrfs_block_group *block_group);
127int btrfs_wait_cache_io(struct btrfs_trans_handle *trans,
128 struct btrfs_block_group *block_group,
129 struct btrfs_path *path);
130int btrfs_write_out_cache(struct btrfs_trans_handle *trans,
131 struct btrfs_block_group *block_group,
132 struct btrfs_path *path);
133
134void btrfs_init_free_space_ctl(struct btrfs_block_group *block_group,
135 struct btrfs_free_space_ctl *ctl);
136int btrfs_add_free_space(struct btrfs_block_group *block_group,
137 u64 bytenr, u64 size);
138int btrfs_add_free_space_unused(struct btrfs_block_group *block_group,
139 u64 bytenr, u64 size);
140int btrfs_add_free_space_async_trimmed(struct btrfs_block_group *block_group,
141 u64 bytenr, u64 size);
142int btrfs_remove_free_space(struct btrfs_block_group *block_group,
143 u64 bytenr, u64 size);
144void btrfs_remove_free_space_cache(struct btrfs_block_group *block_group);
145bool btrfs_is_free_space_trimmed(struct btrfs_block_group *block_group);
146u64 btrfs_find_space_for_alloc(struct btrfs_block_group *block_group,
147 u64 offset, u64 bytes, u64 empty_size,
148 u64 *max_extent_size);
149void btrfs_dump_free_space(struct btrfs_block_group *block_group,
150 u64 bytes);
151int btrfs_find_space_cluster(struct btrfs_block_group *block_group,
152 struct btrfs_free_cluster *cluster,
153 u64 offset, u64 bytes, u64 empty_size);
154void btrfs_init_free_cluster(struct btrfs_free_cluster *cluster);
155u64 btrfs_alloc_from_cluster(struct btrfs_block_group *block_group,
156 struct btrfs_free_cluster *cluster, u64 bytes,
157 u64 min_start, u64 *max_extent_size);
158void btrfs_return_cluster_to_free_space(
159 struct btrfs_block_group *block_group,
160 struct btrfs_free_cluster *cluster);
161int btrfs_trim_block_group(struct btrfs_block_group *block_group,
162 u64 *trimmed, u64 start, u64 end, u64 minlen);
163int btrfs_trim_block_group_extents(struct btrfs_block_group *block_group,
164 u64 *trimmed, u64 start, u64 end, u64 minlen,
165 bool async);
166int btrfs_trim_block_group_bitmaps(struct btrfs_block_group *block_group,
167 u64 *trimmed, u64 start, u64 end, u64 minlen,
168 u64 maxlen, bool async);
169
170bool btrfs_free_space_cache_v1_active(struct btrfs_fs_info *fs_info);
171int btrfs_set_free_space_cache_v1_active(struct btrfs_fs_info *fs_info, bool active);
172/* Support functions for running our sanity tests */
173#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
174int test_add_free_space_entry(struct btrfs_block_group *cache,
175 u64 offset, u64 bytes, bool bitmap);
176int test_check_exists(struct btrfs_block_group *cache, u64 offset, u64 bytes);
177#endif
178
179#endif
180

source code of linux/fs/btrfs/free-space-cache.h