1 /* SPDX-License-Identifier: GPL-2.0 */
2
3 #ifndef BTRFS_SPACE_INFO_H
4 #define BTRFS_SPACE_INFO_H
5
6 #include "volumes.h"
7
8 /*
9 * Different levels for to flush space when doing space reservations.
10 *
11 * The higher the level, the more methods we try to reclaim space.
12 */
13 enum btrfs_reserve_flush_enum {
14 /* If we are in the transaction, we can't flush anything.*/
15 BTRFS_RESERVE_NO_FLUSH,
16
17 /*
18 * Flush space by:
19 * - Running delayed inode items
20 * - Allocating a new chunk
21 */
22 BTRFS_RESERVE_FLUSH_LIMIT,
23
24 /*
25 * Flush space by:
26 * - Running delayed inode items
27 * - Running delayed refs
28 * - Running delalloc and waiting for ordered extents
29 * - Allocating a new chunk
30 * - Committing transaction
31 */
32 BTRFS_RESERVE_FLUSH_EVICT,
33
34 /*
35 * Flush space by above mentioned methods and by:
36 * - Running delayed iputs
37 * - Committing transaction
38 *
39 * Can be interrupted by a fatal signal.
40 */
41 BTRFS_RESERVE_FLUSH_DATA,
42 BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE,
43 BTRFS_RESERVE_FLUSH_ALL,
44
45 /*
46 * Pretty much the same as FLUSH_ALL, but can also steal space from
47 * global rsv.
48 *
49 * Can be interrupted by a fatal signal.
50 */
51 BTRFS_RESERVE_FLUSH_ALL_STEAL,
52
53 /*
54 * This is for btrfs_use_block_rsv only. We have exhausted our block
55 * rsv and our global block rsv. This can happen for things like
56 * delalloc where we are overwriting a lot of extents with a single
57 * extent and didn't reserve enough space. Alternatively it can happen
58 * with delalloc where we reserve 1 extents worth for a large extent but
59 * fragmentation leads to multiple extents being created. This will
60 * give us the reservation in the case of
61 *
62 * if (num_bytes < (space_info->total_bytes -
63 * btrfs_space_info_used(space_info, false))
64 *
65 * Which ignores bytes_may_use. This is potentially dangerous, but our
66 * reservation system is generally pessimistic so is able to absorb this
67 * style of mistake.
68 */
69 BTRFS_RESERVE_FLUSH_EMERGENCY,
70 };
71
72 enum btrfs_flush_state {
73 FLUSH_DELAYED_ITEMS_NR = 1,
74 FLUSH_DELAYED_ITEMS = 2,
75 FLUSH_DELAYED_REFS_NR = 3,
76 FLUSH_DELAYED_REFS = 4,
77 FLUSH_DELALLOC = 5,
78 FLUSH_DELALLOC_WAIT = 6,
79 FLUSH_DELALLOC_FULL = 7,
80 ALLOC_CHUNK = 8,
81 ALLOC_CHUNK_FORCE = 9,
82 RUN_DELAYED_IPUTS = 10,
83 COMMIT_TRANS = 11,
84 };
85
86 struct btrfs_space_info {
87 spinlock_t lock;
88
89 u64 total_bytes; /* total bytes in the space,
90 this doesn't take mirrors into account */
91 u64 bytes_used; /* total bytes used,
92 this doesn't take mirrors into account */
93 u64 bytes_pinned; /* total bytes pinned, will be freed when the
94 transaction finishes */
95 u64 bytes_reserved; /* total bytes the allocator has reserved for
96 current allocations */
97 u64 bytes_may_use; /* number of bytes that may be used for
98 delalloc/allocations */
99 u64 bytes_readonly; /* total bytes that are read only */
100 u64 bytes_zone_unusable; /* total bytes that are unusable until
101 resetting the device zone */
102
103 u64 max_extent_size; /* This will hold the maximum extent size of
104 the space info if we had an ENOSPC in the
105 allocator. */
106 /* Chunk size in bytes */
107 u64 chunk_size;
108
109 /*
110 * Once a block group drops below this threshold (percents) we'll
111 * schedule it for reclaim.
112 */
113 int bg_reclaim_threshold;
114
115 int clamp; /* Used to scale our threshold for preemptive
116 flushing. The value is >> clamp, so turns
117 out to be a 2^clamp divisor. */
118
119 unsigned int full:1; /* indicates that we cannot allocate any more
120 chunks for this space */
121 unsigned int chunk_alloc:1; /* set if we are allocating a chunk */
122
123 unsigned int flush:1; /* set if we are trying to make space */
124
125 unsigned int force_alloc; /* set if we need to force a chunk
126 alloc for this space */
127
128 u64 disk_used; /* total bytes used on disk */
129 u64 disk_total; /* total bytes on disk, takes mirrors into
130 account */
131
132 u64 flags;
133
134 struct list_head list;
135 /* Protected by the spinlock 'lock'. */
136 struct list_head ro_bgs;
137 struct list_head priority_tickets;
138 struct list_head tickets;
139
140 /*
141 * Size of space that needs to be reclaimed in order to satisfy pending
142 * tickets
143 */
144 u64 reclaim_size;
145
146 /*
147 * tickets_id just indicates the next ticket will be handled, so note
148 * it's not stored per ticket.
149 */
150 u64 tickets_id;
151
152 struct rw_semaphore groups_sem;
153 /* for block groups in our same type */
154 struct list_head block_groups[BTRFS_NR_RAID_TYPES];
155
156 struct kobject kobj;
157 struct kobject *block_group_kobjs[BTRFS_NR_RAID_TYPES];
158 };
159
160 struct reserve_ticket {
161 u64 bytes;
162 int error;
163 bool steal;
164 struct list_head list;
165 wait_queue_head_t wait;
166 };
167
btrfs_mixed_space_info(struct btrfs_space_info * space_info)168 static inline bool btrfs_mixed_space_info(struct btrfs_space_info *space_info)
169 {
170 return ((space_info->flags & BTRFS_BLOCK_GROUP_METADATA) &&
171 (space_info->flags & BTRFS_BLOCK_GROUP_DATA));
172 }
173
174 /*
175 *
176 * Declare a helper function to detect underflow of various space info members
177 */
178 #define DECLARE_SPACE_INFO_UPDATE(name, trace_name) \
179 static inline void \
180 btrfs_space_info_update_##name(struct btrfs_fs_info *fs_info, \
181 struct btrfs_space_info *sinfo, \
182 s64 bytes) \
183 { \
184 const u64 abs_bytes = (bytes < 0) ? -bytes : bytes; \
185 lockdep_assert_held(&sinfo->lock); \
186 trace_update_##name(fs_info, sinfo, sinfo->name, bytes); \
187 trace_btrfs_space_reservation(fs_info, trace_name, \
188 sinfo->flags, abs_bytes, \
189 bytes > 0); \
190 if (bytes < 0 && sinfo->name < -bytes) { \
191 WARN_ON(1); \
192 sinfo->name = 0; \
193 return; \
194 } \
195 sinfo->name += bytes; \
196 }
197
198 DECLARE_SPACE_INFO_UPDATE(bytes_may_use, "space_info");
199 DECLARE_SPACE_INFO_UPDATE(bytes_pinned, "pinned");
200 DECLARE_SPACE_INFO_UPDATE(bytes_zone_unusable, "zone_unusable");
201
202 int btrfs_init_space_info(struct btrfs_fs_info *fs_info);
203 void btrfs_add_bg_to_space_info(struct btrfs_fs_info *info,
204 struct btrfs_block_group *block_group);
205 void btrfs_update_space_info_chunk_size(struct btrfs_space_info *space_info,
206 u64 chunk_size);
207 struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
208 u64 flags);
209 u64 __pure btrfs_space_info_used(struct btrfs_space_info *s_info,
210 bool may_use_included);
211 void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
212 void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
213 struct btrfs_space_info *info, u64 bytes,
214 int dump_block_groups);
215 int btrfs_reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
216 struct btrfs_block_rsv *block_rsv,
217 u64 orig_bytes,
218 enum btrfs_reserve_flush_enum flush);
219 void btrfs_try_granting_tickets(struct btrfs_fs_info *fs_info,
220 struct btrfs_space_info *space_info);
221 int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
222 struct btrfs_space_info *space_info, u64 bytes,
223 enum btrfs_reserve_flush_enum flush);
224
btrfs_space_info_free_bytes_may_use(struct btrfs_fs_info * fs_info,struct btrfs_space_info * space_info,u64 num_bytes)225 static inline void btrfs_space_info_free_bytes_may_use(
226 struct btrfs_fs_info *fs_info,
227 struct btrfs_space_info *space_info,
228 u64 num_bytes)
229 {
230 spin_lock(&space_info->lock);
231 btrfs_space_info_update_bytes_may_use(fs_info, space_info, -num_bytes);
232 btrfs_try_granting_tickets(fs_info, space_info);
233 spin_unlock(&space_info->lock);
234 }
235 int btrfs_reserve_data_bytes(struct btrfs_fs_info *fs_info, u64 bytes,
236 enum btrfs_reserve_flush_enum flush);
237 void btrfs_dump_space_info_for_trans_abort(struct btrfs_fs_info *fs_info);
238 void btrfs_init_async_reclaim_work(struct btrfs_fs_info *fs_info);
239 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo);
240
241 #endif /* BTRFS_SPACE_INFO_H */
242