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
15struct btrfs_fs_info;
16struct 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 */
23enum 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
82enum btrfs_flush_state {
83	FLUSH_DELAYED_ITEMS_NR	= 1,
84	FLUSH_DELAYED_ITEMS	= 2,
85	FLUSH_DELAYED_REFS_NR	= 3,
86	FLUSH_DELAYED_REFS	= 4,
87	FLUSH_DELALLOC		= 5,
88	FLUSH_DELALLOC_WAIT	= 6,
89	FLUSH_DELALLOC_FULL	= 7,
90	ALLOC_CHUNK		= 8,
91	ALLOC_CHUNK_FORCE	= 9,
92	RUN_DELAYED_IPUTS	= 10,
93	COMMIT_TRANS		= 11,
94};
95
96struct btrfs_space_info {
97	spinlock_t lock;
98
99	u64 total_bytes;	/* total bytes in the space,
100				   this doesn't take mirrors into account */
101	u64 bytes_used;		/* total bytes used,
102				   this doesn't take mirrors into account */
103	u64 bytes_pinned;	/* total bytes pinned, will be freed when the
104				   transaction finishes */
105	u64 bytes_reserved;	/* total bytes the allocator has reserved for
106				   current allocations */
107	u64 bytes_may_use;	/* number of bytes that may be used for
108				   delalloc/allocations */
109	u64 bytes_readonly;	/* total bytes that are read only */
110	u64 bytes_zone_unusable;	/* total bytes that are unusable until
111					   resetting the device zone */
112
113	u64 max_extent_size;	/* This will hold the maximum extent size of
114				   the space info if we had an ENOSPC in the
115				   allocator. */
116	/* Chunk size in bytes */
117	u64 chunk_size;
118
119	/*
120	 * Once a block group drops below this threshold (percents) we'll
121	 * schedule it for reclaim.
122	 */
123	int bg_reclaim_threshold;
124
125	int clamp;		/* Used to scale our threshold for preemptive
126				   flushing. The value is >> clamp, so turns
127				   out to be a 2^clamp divisor. */
128
129	unsigned int full:1;	/* indicates that we cannot allocate any more
130				   chunks for this space */
131	unsigned int chunk_alloc:1;	/* set if we are allocating a chunk */
132
133	unsigned int flush:1;		/* set if we are trying to make space */
134
135	unsigned int force_alloc;	/* set if we need to force a chunk
136					   alloc for this space */
137
138	u64 disk_used;		/* total bytes used on disk */
139	u64 disk_total;		/* total bytes on disk, takes mirrors into
140				   account */
141
142	u64 flags;
143
144	struct list_head list;
145	/* Protected by the spinlock 'lock'. */
146	struct list_head ro_bgs;
147	struct list_head priority_tickets;
148	struct list_head tickets;
149
150	/*
151	 * Size of space that needs to be reclaimed in order to satisfy pending
152	 * tickets
153	 */
154	u64 reclaim_size;
155
156	/*
157	 * tickets_id just indicates the next ticket will be handled, so note
158	 * it's not stored per ticket.
159	 */
160	u64 tickets_id;
161
162	struct rw_semaphore groups_sem;
163	/* for block groups in our same type */
164	struct list_head block_groups[BTRFS_NR_RAID_TYPES];
165
166	struct kobject kobj;
167	struct kobject *block_group_kobjs[BTRFS_NR_RAID_TYPES];
168};
169
170struct reserve_ticket {
171	u64 bytes;
172	int error;
173	bool steal;
174	struct list_head list;
175	wait_queue_head_t wait;
176};
177
178static inline bool btrfs_mixed_space_info(struct btrfs_space_info *space_info)
179{
180	return ((space_info->flags & BTRFS_BLOCK_GROUP_METADATA) &&
181		(space_info->flags & BTRFS_BLOCK_GROUP_DATA));
182}
183
184/*
185 *
186 * Declare a helper function to detect underflow of various space info members
187 */
188#define DECLARE_SPACE_INFO_UPDATE(name, trace_name)			\
189static inline void							\
190btrfs_space_info_update_##name(struct btrfs_fs_info *fs_info,		\
191			       struct btrfs_space_info *sinfo,		\
192			       s64 bytes)				\
193{									\
194	const u64 abs_bytes = (bytes < 0) ? -bytes : bytes;		\
195	lockdep_assert_held(&sinfo->lock);				\
196	trace_update_##name(fs_info, sinfo, sinfo->name, bytes);	\
197	trace_btrfs_space_reservation(fs_info, trace_name,		\
198				      sinfo->flags, abs_bytes,		\
199				      bytes > 0);			\
200	if (bytes < 0 && sinfo->name < -bytes) {			\
201		WARN_ON(1);						\
202		sinfo->name = 0;					\
203		return;							\
204	}								\
205	sinfo->name += bytes;						\
206}
207
208DECLARE_SPACE_INFO_UPDATE(bytes_may_use, "space_info");
209DECLARE_SPACE_INFO_UPDATE(bytes_pinned, "pinned");
210
211int btrfs_init_space_info(struct btrfs_fs_info *fs_info);
212void btrfs_add_bg_to_space_info(struct btrfs_fs_info *info,
213				struct btrfs_block_group *block_group);
214void btrfs_update_space_info_chunk_size(struct btrfs_space_info *space_info,
215					u64 chunk_size);
216struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
217					       u64 flags);
218u64 __pure btrfs_space_info_used(struct btrfs_space_info *s_info,
219			  bool may_use_included);
220void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
221void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
222			   struct btrfs_space_info *info, u64 bytes,
223			   int dump_block_groups);
224int btrfs_reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
225				 struct btrfs_space_info *space_info,
226				 u64 orig_bytes,
227				 enum btrfs_reserve_flush_enum flush);
228void btrfs_try_granting_tickets(struct btrfs_fs_info *fs_info,
229				struct btrfs_space_info *space_info);
230int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
231			 struct btrfs_space_info *space_info, u64 bytes,
232			 enum btrfs_reserve_flush_enum flush);
233
234static inline void btrfs_space_info_free_bytes_may_use(
235				struct btrfs_fs_info *fs_info,
236				struct btrfs_space_info *space_info,
237				u64 num_bytes)
238{
239	spin_lock(&space_info->lock);
240	btrfs_space_info_update_bytes_may_use(fs_info, space_info, -num_bytes);
241	btrfs_try_granting_tickets(fs_info, space_info);
242	spin_unlock(&space_info->lock);
243}
244int btrfs_reserve_data_bytes(struct btrfs_fs_info *fs_info, u64 bytes,
245			     enum btrfs_reserve_flush_enum flush);
246void btrfs_dump_space_info_for_trans_abort(struct btrfs_fs_info *fs_info);
247void btrfs_init_async_reclaim_work(struct btrfs_fs_info *fs_info);
248u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo);
249
250#endif /* BTRFS_SPACE_INFO_H */
251