xref: /kernel/linux/linux-6.6/fs/btrfs/space-info.h (revision 62306a36)
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 */
13enum 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
72enum 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
86struct 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
160struct reserve_ticket {
161	u64 bytes;
162	int error;
163	bool steal;
164	struct list_head list;
165	wait_queue_head_t wait;
166};
167
168static 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)			\
179static inline void							\
180btrfs_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
198DECLARE_SPACE_INFO_UPDATE(bytes_may_use, "space_info");
199DECLARE_SPACE_INFO_UPDATE(bytes_pinned, "pinned");
200
201int btrfs_init_space_info(struct btrfs_fs_info *fs_info);
202void btrfs_add_bg_to_space_info(struct btrfs_fs_info *info,
203				struct btrfs_block_group *block_group);
204void btrfs_update_space_info_chunk_size(struct btrfs_space_info *space_info,
205					u64 chunk_size);
206struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
207					       u64 flags);
208u64 __pure btrfs_space_info_used(struct btrfs_space_info *s_info,
209			  bool may_use_included);
210void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
211void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
212			   struct btrfs_space_info *info, u64 bytes,
213			   int dump_block_groups);
214int btrfs_reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
215				 struct btrfs_block_rsv *block_rsv,
216				 u64 orig_bytes,
217				 enum btrfs_reserve_flush_enum flush);
218void btrfs_try_granting_tickets(struct btrfs_fs_info *fs_info,
219				struct btrfs_space_info *space_info);
220int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
221			 struct btrfs_space_info *space_info, u64 bytes,
222			 enum btrfs_reserve_flush_enum flush);
223
224static inline void btrfs_space_info_free_bytes_may_use(
225				struct btrfs_fs_info *fs_info,
226				struct btrfs_space_info *space_info,
227				u64 num_bytes)
228{
229	spin_lock(&space_info->lock);
230	btrfs_space_info_update_bytes_may_use(fs_info, space_info, -num_bytes);
231	btrfs_try_granting_tickets(fs_info, space_info);
232	spin_unlock(&space_info->lock);
233}
234int btrfs_reserve_data_bytes(struct btrfs_fs_info *fs_info, u64 bytes,
235			     enum btrfs_reserve_flush_enum flush);
236void btrfs_dump_space_info_for_trans_abort(struct btrfs_fs_info *fs_info);
237void btrfs_init_async_reclaim_work(struct btrfs_fs_info *fs_info);
238u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo);
239
240#endif /* BTRFS_SPACE_INFO_H */
241