xref: /linux/fs/btrfs/space-info.h (revision c92b4d3dd59f9f71ac34b42d4603d2323a499ab0)
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 	/*
25 	 * Used when we can't flush or don't need:
26 	 *
27 	 * 1) We are holding a transaction handle open, so we can't flush as
28 	 *    that could deadlock.
29 	 *
30 	 * 2) For a nowait write we don't want to block when reserving delalloc.
31 	 *
32 	 * 3) Joining a transaction or attaching a transaction, we don't want
33 	 *    to wait and we don't need to reserve anything (any needed space
34 	 *    was reserved before in a dedicated block reserve, or we rely on
35 	 *    the global block reserve, see btrfs_init_root_block_rsv()).
36 	 *
37 	 * 4) Starting a transaction when we don't need to reserve space, as
38 	 *    we don't need it because we previously reserved in a dedicated
39 	 *    block reserve or rely on the global block reserve, like the above
40 	 *    case.
41 	 */
42 	BTRFS_RESERVE_NO_FLUSH,
43 
44 	/*
45 	 * Flush space by:
46 	 * - Running delayed inode items
47 	 * - Allocating a new chunk
48 	 */
49 	BTRFS_RESERVE_FLUSH_LIMIT,
50 
51 	/*
52 	 * Flush space by:
53 	 * - Running delayed inode items
54 	 * - Running delayed refs
55 	 * - Running delalloc and waiting for ordered extents
56 	 * - Allocating a new chunk
57 	 * - Committing transaction
58 	 */
59 	BTRFS_RESERVE_FLUSH_EVICT,
60 
61 	/*
62 	 * Flush space by above mentioned methods and by:
63 	 * - Running delayed iputs
64 	 * - Committing transaction
65 	 *
66 	 * Can be interrupted by a fatal signal.
67 	 */
68 	BTRFS_RESERVE_FLUSH_DATA,
69 	BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE,
70 	BTRFS_RESERVE_FLUSH_ALL,
71 
72 	/*
73 	 * Pretty much the same as FLUSH_ALL, but can also steal space from
74 	 * global rsv.
75 	 *
76 	 * Can be interrupted by a fatal signal.
77 	 */
78 	BTRFS_RESERVE_FLUSH_ALL_STEAL,
79 
80 	/*
81 	 * This is for btrfs_use_block_rsv only.  We have exhausted our block
82 	 * rsv and our global block rsv.  This can happen for things like
83 	 * delalloc where we are overwriting a lot of extents with a single
84 	 * extent and didn't reserve enough space.  Alternatively it can happen
85 	 * with delalloc where we reserve 1 extents worth for a large extent but
86 	 * fragmentation leads to multiple extents being created.  This will
87 	 * give us the reservation in the case of
88 	 *
89 	 * if (num_bytes < (space_info->total_bytes -
90 	 *		    btrfs_space_info_used(space_info, false))
91 	 *
92 	 * Which ignores bytes_may_use.  This is potentially dangerous, but our
93 	 * reservation system is generally pessimistic so is able to absorb this
94 	 * style of mistake.
95 	 */
96 	BTRFS_RESERVE_FLUSH_EMERGENCY,
97 };
98 
99 /*
100  * Please be aware that the order of enum values will be the order of the reclaim
101  * process in btrfs_async_reclaim_metadata_space().
102  */
103 enum btrfs_flush_state {
104 	FLUSH_DELAYED_ITEMS_NR	= 1,
105 	FLUSH_DELAYED_ITEMS	= 2,
106 	FLUSH_DELAYED_REFS_NR	= 3,
107 	FLUSH_DELAYED_REFS	= 4,
108 	FLUSH_DELALLOC		= 5,
109 	FLUSH_DELALLOC_WAIT	= 6,
110 	FLUSH_DELALLOC_FULL	= 7,
111 	ALLOC_CHUNK		= 8,
112 	ALLOC_CHUNK_FORCE	= 9,
113 	RUN_DELAYED_IPUTS	= 10,
114 	COMMIT_TRANS		= 11,
115 	RESET_ZONES		= 12,
116 	RECLAIM_ZONES		= 13,
117 };
118 
119 enum btrfs_space_info_sub_group {
120 	BTRFS_SUB_GROUP_PRIMARY,
121 	BTRFS_SUB_GROUP_DATA_RELOC,
122 	BTRFS_SUB_GROUP_TREELOG,
123 };
124 
125 #define BTRFS_SPACE_INFO_SUB_GROUP_MAX 1
126 struct btrfs_space_info {
127 	struct btrfs_fs_info *fs_info;
128 	struct btrfs_space_info *parent;
129 	struct btrfs_space_info *sub_group[BTRFS_SPACE_INFO_SUB_GROUP_MAX];
130 	int subgroup_id;
131 	spinlock_t lock;
132 
133 	u64 total_bytes;	/* total bytes in the space,
134 				   this doesn't take mirrors into account */
135 	u64 bytes_used;		/* total bytes used,
136 				   this doesn't take mirrors into account */
137 	u64 bytes_pinned;	/* total bytes pinned, will be freed when the
138 				   transaction finishes */
139 	u64 bytes_reserved;	/* total bytes the allocator has reserved for
140 				   current allocations */
141 	u64 bytes_may_use;	/* number of bytes that may be used for
142 				   delalloc/allocations */
143 	u64 bytes_readonly;	/* total bytes that are read only */
144 	u64 bytes_zone_unusable;	/* total bytes that are unusable until
145 					   resetting the device zone */
146 
147 	u64 max_extent_size;	/* This will hold the maximum extent size of
148 				   the space info if we had an ENOSPC in the
149 				   allocator. */
150 	/* Chunk size in bytes */
151 	u64 chunk_size;
152 
153 	/*
154 	 * Once a block group drops below this threshold (percents) we'll
155 	 * schedule it for reclaim.
156 	 */
157 	int bg_reclaim_threshold;
158 
159 	int clamp;		/* Used to scale our threshold for preemptive
160 				   flushing. The value is >> clamp, so turns
161 				   out to be a 2^clamp divisor. */
162 
163 	bool full;		/* indicates that we cannot allocate any more
164 				   chunks for this space */
165 	bool chunk_alloc;	/* set if we are allocating a chunk */
166 
167 	bool flush;		/* set if we are trying to make space */
168 
169 	unsigned int force_alloc;	/* set if we need to force a chunk
170 					   alloc for this space */
171 
172 	u64 disk_used;		/* total bytes used on disk */
173 	u64 disk_total;		/* total bytes on disk, takes mirrors into
174 				   account */
175 
176 	u64 flags;
177 
178 	struct list_head list;
179 	/* Protected by the spinlock 'lock'. */
180 	struct list_head ro_bgs;
181 	struct list_head priority_tickets;
182 	struct list_head tickets;
183 
184 	/*
185 	 * Size of space that needs to be reclaimed in order to satisfy pending
186 	 * tickets
187 	 */
188 	u64 reclaim_size;
189 
190 	/*
191 	 * tickets_id just indicates the next ticket will be handled, so note
192 	 * it's not stored per ticket.
193 	 */
194 	u64 tickets_id;
195 
196 	struct rw_semaphore groups_sem;
197 	/* for block groups in our same type */
198 	struct list_head block_groups[BTRFS_NR_RAID_TYPES];
199 
200 	struct kobject kobj;
201 	struct kobject *block_group_kobjs[BTRFS_NR_RAID_TYPES];
202 
203 	/*
204 	 * Monotonically increasing counter of block group reclaim attempts
205 	 * Exposed in /sys/fs/<uuid>/allocation/<type>/reclaim_count
206 	 */
207 	u64 reclaim_count;
208 
209 	/*
210 	 * Monotonically increasing counter of reclaimed bytes
211 	 * Exposed in /sys/fs/<uuid>/allocation/<type>/reclaim_bytes
212 	 */
213 	u64 reclaim_bytes;
214 
215 	/*
216 	 * Monotonically increasing counter of reclaim errors
217 	 * Exposed in /sys/fs/<uuid>/allocation/<type>/reclaim_errors
218 	 */
219 	u64 reclaim_errors;
220 
221 	/*
222 	 * If true, use the dynamic relocation threshold, instead of the
223 	 * fixed bg_reclaim_threshold.
224 	 */
225 	bool dynamic_reclaim;
226 
227 	/*
228 	 * Periodically check all block groups against the reclaim
229 	 * threshold in the cleaner thread.
230 	 */
231 	bool periodic_reclaim;
232 
233 	/*
234 	 * Periodic reclaim should be a no-op if a space_info hasn't
235 	 * freed any space since the last time we tried.
236 	 */
237 	bool periodic_reclaim_ready;
238 
239 	/*
240 	 * Net bytes freed or allocated since the last reclaim pass.
241 	 */
242 	s64 reclaimable_bytes;
243 };
244 
btrfs_mixed_space_info(const struct btrfs_space_info * space_info)245 static inline bool btrfs_mixed_space_info(const struct btrfs_space_info *space_info)
246 {
247 	return ((space_info->flags & BTRFS_BLOCK_GROUP_METADATA) &&
248 		(space_info->flags & BTRFS_BLOCK_GROUP_DATA));
249 }
250 
251 /*
252  *
253  * Declare a helper function to detect underflow of various space info members
254  */
255 #define DECLARE_SPACE_INFO_UPDATE(name, trace_name)			\
256 static inline void							\
257 btrfs_space_info_update_##name(struct btrfs_space_info *sinfo,		\
258 			       s64 bytes)				\
259 {									\
260 	struct btrfs_fs_info *fs_info = sinfo->fs_info;			\
261 	const u64 abs_bytes = (bytes < 0) ? -bytes : bytes;		\
262 	lockdep_assert_held(&sinfo->lock);				\
263 	trace_update_##name(fs_info, sinfo, sinfo->name, bytes);	\
264 	trace_btrfs_space_reservation(fs_info, trace_name,		\
265 				      sinfo->flags, abs_bytes,		\
266 				      bytes > 0);			\
267 	if (bytes < 0 && sinfo->name < -bytes) {			\
268 		WARN_ON(1);						\
269 		sinfo->name = 0;					\
270 		return;							\
271 	}								\
272 	sinfo->name += bytes;						\
273 }
274 
275 DECLARE_SPACE_INFO_UPDATE(bytes_may_use, "space_info");
276 DECLARE_SPACE_INFO_UPDATE(bytes_pinned, "pinned");
277 DECLARE_SPACE_INFO_UPDATE(bytes_zone_unusable, "zone_unusable");
278 
btrfs_space_info_used(const struct btrfs_space_info * s_info,bool may_use_included)279 static inline u64 btrfs_space_info_used(const struct btrfs_space_info *s_info,
280 					bool may_use_included)
281 {
282 	lockdep_assert_held(&s_info->lock);
283 
284 	return s_info->bytes_used + s_info->bytes_reserved +
285 		s_info->bytes_pinned + s_info->bytes_readonly +
286 		s_info->bytes_zone_unusable +
287 		(may_use_included ? s_info->bytes_may_use : 0);
288 }
289 
290 int btrfs_init_space_info(struct btrfs_fs_info *fs_info);
291 void btrfs_add_bg_to_space_info(struct btrfs_fs_info *info,
292 				struct btrfs_block_group *block_group);
293 void btrfs_update_space_info_chunk_size(struct btrfs_space_info *space_info,
294 					u64 chunk_size);
295 struct btrfs_space_info *btrfs_find_space_info(const struct btrfs_fs_info *info,
296 					       u64 flags);
297 void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
298 void btrfs_dump_space_info(struct btrfs_space_info *info, u64 bytes,
299 			   bool dump_block_groups);
300 int btrfs_reserve_metadata_bytes(struct btrfs_space_info *space_info,
301 				 u64 orig_bytes,
302 				 enum btrfs_reserve_flush_enum flush);
303 void btrfs_try_granting_tickets(struct btrfs_space_info *space_info);
304 bool btrfs_can_overcommit(const struct btrfs_space_info *space_info, u64 bytes,
305 			  enum btrfs_reserve_flush_enum flush);
306 
btrfs_space_info_free_bytes_may_use(struct btrfs_space_info * space_info,u64 num_bytes)307 static inline void btrfs_space_info_free_bytes_may_use(
308 				struct btrfs_space_info *space_info,
309 				u64 num_bytes)
310 {
311 	spin_lock(&space_info->lock);
312 	btrfs_space_info_update_bytes_may_use(space_info, -num_bytes);
313 	btrfs_try_granting_tickets(space_info);
314 	spin_unlock(&space_info->lock);
315 }
316 int btrfs_reserve_data_bytes(struct btrfs_space_info *space_info, u64 bytes,
317 			     enum btrfs_reserve_flush_enum flush);
318 void btrfs_dump_space_info_for_trans_abort(struct btrfs_fs_info *fs_info);
319 void btrfs_init_async_reclaim_work(struct btrfs_fs_info *fs_info);
320 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo);
321 
322 void btrfs_space_info_update_reclaimable(struct btrfs_space_info *space_info, s64 bytes);
323 void btrfs_set_periodic_reclaim_ready(struct btrfs_space_info *space_info, bool ready);
324 int btrfs_calc_reclaim_threshold(const struct btrfs_space_info *space_info);
325 void btrfs_reclaim_sweep(const struct btrfs_fs_info *fs_info);
326 void btrfs_return_free_space(struct btrfs_space_info *space_info, u64 len);
327 
btrfs_space_info_type_str(const struct btrfs_space_info * space_info)328 static inline const char *btrfs_space_info_type_str(const struct btrfs_space_info *space_info)
329 {
330 	switch (space_info->flags) {
331 	case BTRFS_BLOCK_GROUP_SYSTEM:
332 		return "SYSTEM";
333 	case BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA:
334 		return "DATA+METADATA";
335 	case BTRFS_BLOCK_GROUP_DATA:
336 		return "DATA";
337 	case BTRFS_BLOCK_GROUP_METADATA:
338 		return "METADATA";
339 	default:
340 		return "UNKNOWN";
341 	}
342 }
343 
344 #endif /* BTRFS_SPACE_INFO_H */
345