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