xref: /linux/fs/btrfs/space-info.h (revision f92b71ffca8c7e45e194aecc85e31bd11582f4d2)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 
3 #ifndef BTRFS_SPACE_INFO_H
4 #define BTRFS_SPACE_INFO_H
5 
6 #include <trace/events/btrfs.h>
7 #include <linux/spinlock.h>
8 #include <linux/list.h>
9 #include <linux/kobject.h>
10 #include <linux/lockdep.h>
11 #include <linux/wait.h>
12 #include <linux/rwsem.h>
13 #include "volumes.h"
14 
15 struct btrfs_fs_info;
16 struct btrfs_block_group;
17 
18 /*
19  * Different levels for to flush space when doing space reservations.
20  *
21  * The higher the level, the more methods we try to reclaim space.
22  */
23 enum btrfs_reserve_flush_enum {
24 	/* If we are in the transaction, we can't flush anything.*/
25 	BTRFS_RESERVE_NO_FLUSH,
26 
27 	/*
28 	 * Flush space by:
29 	 * - Running delayed inode items
30 	 * - Allocating a new chunk
31 	 */
32 	BTRFS_RESERVE_FLUSH_LIMIT,
33 
34 	/*
35 	 * Flush space by:
36 	 * - Running delayed inode items
37 	 * - Running delayed refs
38 	 * - Running delalloc and waiting for ordered extents
39 	 * - Allocating a new chunk
40 	 * - Committing transaction
41 	 */
42 	BTRFS_RESERVE_FLUSH_EVICT,
43 
44 	/*
45 	 * Flush space by above mentioned methods and by:
46 	 * - Running delayed iputs
47 	 * - Committing transaction
48 	 *
49 	 * Can be interrupted by a fatal signal.
50 	 */
51 	BTRFS_RESERVE_FLUSH_DATA,
52 	BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE,
53 	BTRFS_RESERVE_FLUSH_ALL,
54 
55 	/*
56 	 * Pretty much the same as FLUSH_ALL, but can also steal space from
57 	 * global rsv.
58 	 *
59 	 * Can be interrupted by a fatal signal.
60 	 */
61 	BTRFS_RESERVE_FLUSH_ALL_STEAL,
62 
63 	/*
64 	 * This is for btrfs_use_block_rsv only.  We have exhausted our block
65 	 * rsv and our global block rsv.  This can happen for things like
66 	 * delalloc where we are overwriting a lot of extents with a single
67 	 * extent and didn't reserve enough space.  Alternatively it can happen
68 	 * with delalloc where we reserve 1 extents worth for a large extent but
69 	 * fragmentation leads to multiple extents being created.  This will
70 	 * give us the reservation in the case of
71 	 *
72 	 * if (num_bytes < (space_info->total_bytes -
73 	 *		    btrfs_space_info_used(space_info, false))
74 	 *
75 	 * Which ignores bytes_may_use.  This is potentially dangerous, but our
76 	 * reservation system is generally pessimistic so is able to absorb this
77 	 * style of mistake.
78 	 */
79 	BTRFS_RESERVE_FLUSH_EMERGENCY,
80 };
81 
82 /*
83  * Please be aware that the order of enum values will be the order of the reclaim
84  * process in btrfs_async_reclaim_metadata_space().
85  */
86 enum btrfs_flush_state {
87 	FLUSH_DELAYED_ITEMS_NR	= 1,
88 	FLUSH_DELAYED_ITEMS	= 2,
89 	FLUSH_DELAYED_REFS_NR	= 3,
90 	FLUSH_DELAYED_REFS	= 4,
91 	FLUSH_DELALLOC		= 5,
92 	FLUSH_DELALLOC_WAIT	= 6,
93 	FLUSH_DELALLOC_FULL	= 7,
94 	ALLOC_CHUNK		= 8,
95 	ALLOC_CHUNK_FORCE	= 9,
96 	RUN_DELAYED_IPUTS	= 10,
97 	COMMIT_TRANS		= 11,
98 	RESET_ZONES		= 12,
99 };
100 
101 enum btrfs_space_info_sub_group {
102 	BTRFS_SUB_GROUP_PRIMARY,
103 	BTRFS_SUB_GROUP_DATA_RELOC,
104 	BTRFS_SUB_GROUP_TREELOG,
105 };
106 
107 #define BTRFS_SPACE_INFO_SUB_GROUP_MAX 1
108 struct btrfs_space_info {
109 	struct btrfs_fs_info *fs_info;
110 	struct btrfs_space_info *parent;
111 	struct btrfs_space_info *sub_group[BTRFS_SPACE_INFO_SUB_GROUP_MAX];
112 	int subgroup_id;
113 	spinlock_t lock;
114 
115 	u64 total_bytes;	/* total bytes in the space,
116 				   this doesn't take mirrors into account */
117 	u64 bytes_used;		/* total bytes used,
118 				   this doesn't take mirrors into account */
119 	u64 bytes_pinned;	/* total bytes pinned, will be freed when the
120 				   transaction finishes */
121 	u64 bytes_reserved;	/* total bytes the allocator has reserved for
122 				   current allocations */
123 	u64 bytes_may_use;	/* number of bytes that may be used for
124 				   delalloc/allocations */
125 	u64 bytes_readonly;	/* total bytes that are read only */
126 	u64 bytes_zone_unusable;	/* total bytes that are unusable until
127 					   resetting the device zone */
128 
129 	u64 max_extent_size;	/* This will hold the maximum extent size of
130 				   the space info if we had an ENOSPC in the
131 				   allocator. */
132 	/* Chunk size in bytes */
133 	u64 chunk_size;
134 
135 	/*
136 	 * Once a block group drops below this threshold (percents) we'll
137 	 * schedule it for reclaim.
138 	 */
139 	int bg_reclaim_threshold;
140 
141 	int clamp;		/* Used to scale our threshold for preemptive
142 				   flushing. The value is >> clamp, so turns
143 				   out to be a 2^clamp divisor. */
144 
145 	unsigned int full:1;	/* indicates that we cannot allocate any more
146 				   chunks for this space */
147 	unsigned int chunk_alloc:1;	/* set if we are allocating a chunk */
148 
149 	unsigned int flush:1;		/* set if we are trying to make space */
150 
151 	unsigned int force_alloc;	/* set if we need to force a chunk
152 					   alloc for this space */
153 
154 	u64 disk_used;		/* total bytes used on disk */
155 	u64 disk_total;		/* total bytes on disk, takes mirrors into
156 				   account */
157 
158 	u64 flags;
159 
160 	struct list_head list;
161 	/* Protected by the spinlock 'lock'. */
162 	struct list_head ro_bgs;
163 	struct list_head priority_tickets;
164 	struct list_head tickets;
165 
166 	/*
167 	 * Size of space that needs to be reclaimed in order to satisfy pending
168 	 * tickets
169 	 */
170 	u64 reclaim_size;
171 
172 	/*
173 	 * tickets_id just indicates the next ticket will be handled, so note
174 	 * it's not stored per ticket.
175 	 */
176 	u64 tickets_id;
177 
178 	struct rw_semaphore groups_sem;
179 	/* for block groups in our same type */
180 	struct list_head block_groups[BTRFS_NR_RAID_TYPES];
181 
182 	struct kobject kobj;
183 	struct kobject *block_group_kobjs[BTRFS_NR_RAID_TYPES];
184 
185 	/*
186 	 * Monotonically increasing counter of block group reclaim attempts
187 	 * Exposed in /sys/fs/<uuid>/allocation/<type>/reclaim_count
188 	 */
189 	u64 reclaim_count;
190 
191 	/*
192 	 * Monotonically increasing counter of reclaimed bytes
193 	 * Exposed in /sys/fs/<uuid>/allocation/<type>/reclaim_bytes
194 	 */
195 	u64 reclaim_bytes;
196 
197 	/*
198 	 * Monotonically increasing counter of reclaim errors
199 	 * Exposed in /sys/fs/<uuid>/allocation/<type>/reclaim_errors
200 	 */
201 	u64 reclaim_errors;
202 
203 	/*
204 	 * If true, use the dynamic relocation threshold, instead of the
205 	 * fixed bg_reclaim_threshold.
206 	 */
207 	bool dynamic_reclaim;
208 
209 	/*
210 	 * Periodically check all block groups against the reclaim
211 	 * threshold in the cleaner thread.
212 	 */
213 	bool periodic_reclaim;
214 
215 	/*
216 	 * Periodic reclaim should be a no-op if a space_info hasn't
217 	 * freed any space since the last time we tried.
218 	 */
219 	bool periodic_reclaim_ready;
220 
221 	/*
222 	 * Net bytes freed or allocated since the last reclaim pass.
223 	 */
224 	s64 reclaimable_bytes;
225 };
226 
227 struct reserve_ticket {
228 	u64 bytes;
229 	int error;
230 	bool steal;
231 	struct list_head list;
232 	wait_queue_head_t wait;
233 };
234 
btrfs_mixed_space_info(const struct btrfs_space_info * space_info)235 static inline bool btrfs_mixed_space_info(const struct btrfs_space_info *space_info)
236 {
237 	return ((space_info->flags & BTRFS_BLOCK_GROUP_METADATA) &&
238 		(space_info->flags & BTRFS_BLOCK_GROUP_DATA));
239 }
240 
241 /*
242  *
243  * Declare a helper function to detect underflow of various space info members
244  */
245 #define DECLARE_SPACE_INFO_UPDATE(name, trace_name)			\
246 static inline void							\
247 btrfs_space_info_update_##name(struct btrfs_space_info *sinfo,		\
248 			       s64 bytes)				\
249 {									\
250 	struct btrfs_fs_info *fs_info = sinfo->fs_info;			\
251 	const u64 abs_bytes = (bytes < 0) ? -bytes : bytes;		\
252 	lockdep_assert_held(&sinfo->lock);				\
253 	trace_update_##name(fs_info, sinfo, sinfo->name, bytes);	\
254 	trace_btrfs_space_reservation(fs_info, trace_name,		\
255 				      sinfo->flags, abs_bytes,		\
256 				      bytes > 0);			\
257 	if (bytes < 0 && sinfo->name < -bytes) {			\
258 		WARN_ON(1);						\
259 		sinfo->name = 0;					\
260 		return;							\
261 	}								\
262 	sinfo->name += bytes;						\
263 }
264 
265 DECLARE_SPACE_INFO_UPDATE(bytes_may_use, "space_info");
266 DECLARE_SPACE_INFO_UPDATE(bytes_pinned, "pinned");
267 DECLARE_SPACE_INFO_UPDATE(bytes_zone_unusable, "zone_unusable");
268 
269 int btrfs_init_space_info(struct btrfs_fs_info *fs_info);
270 void btrfs_add_bg_to_space_info(struct btrfs_fs_info *info,
271 				struct btrfs_block_group *block_group);
272 void btrfs_update_space_info_chunk_size(struct btrfs_space_info *space_info,
273 					u64 chunk_size);
274 struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
275 					       u64 flags);
276 u64 __pure btrfs_space_info_used(const struct btrfs_space_info *s_info,
277 			  bool may_use_included);
278 void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
279 void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
280 			   struct btrfs_space_info *info, u64 bytes,
281 			   bool dump_block_groups);
282 int btrfs_reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
283 				 struct btrfs_space_info *space_info,
284 				 u64 orig_bytes,
285 				 enum btrfs_reserve_flush_enum flush);
286 void btrfs_try_granting_tickets(struct btrfs_fs_info *fs_info,
287 				struct btrfs_space_info *space_info);
288 int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
289 			 const struct btrfs_space_info *space_info, u64 bytes,
290 			 enum btrfs_reserve_flush_enum flush);
291 
btrfs_space_info_free_bytes_may_use(struct btrfs_space_info * space_info,u64 num_bytes)292 static inline void btrfs_space_info_free_bytes_may_use(
293 				struct btrfs_space_info *space_info,
294 				u64 num_bytes)
295 {
296 	spin_lock(&space_info->lock);
297 	btrfs_space_info_update_bytes_may_use(space_info, -num_bytes);
298 	btrfs_try_granting_tickets(space_info->fs_info, space_info);
299 	spin_unlock(&space_info->lock);
300 }
301 int btrfs_reserve_data_bytes(struct btrfs_space_info *space_info, u64 bytes,
302 			     enum btrfs_reserve_flush_enum flush);
303 void btrfs_dump_space_info_for_trans_abort(struct btrfs_fs_info *fs_info);
304 void btrfs_init_async_reclaim_work(struct btrfs_fs_info *fs_info);
305 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo);
306 
307 void btrfs_space_info_update_reclaimable(struct btrfs_space_info *space_info, s64 bytes);
308 void btrfs_set_periodic_reclaim_ready(struct btrfs_space_info *space_info, bool ready);
309 int btrfs_calc_reclaim_threshold(const struct btrfs_space_info *space_info);
310 void btrfs_reclaim_sweep(const struct btrfs_fs_info *fs_info);
311 void btrfs_return_free_space(struct btrfs_space_info *space_info, u64 len);
312 
313 #endif /* BTRFS_SPACE_INFO_H */
314