1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Copyright (C) 2007 Oracle. All rights reserved.
6 #ifndef BTRFS_TRANSACTION_H
7 #define BTRFS_TRANSACTION_H
9 #include <linux/atomic.h>
10 #include <linux/refcount.h>
11 #include <linux/list.h>
12 #include <linux/time64.h>
13 #include <linux/mutex.h>
14 #include <linux/wait.h>
15 #include "btrfs_inode.h"
16 #include "delayed-ref.h"
17 #include "extent-io-tree.h"
18 #include "block-rsv.h"
24 struct btrfs_pending_snapshot
;
26 struct btrfs_root_item
;
31 * Signal that a direct IO write is in progress, to avoid deadlock for sync
32 * direct IO writes when fsync is called during the direct IO write path.
34 #define BTRFS_TRANS_DIO_WRITE_STUB ((void *) 1)
36 /* Radix-tree tag for roots that are part of the trasaction. */
37 #define BTRFS_ROOT_TRANS_TAG 0
39 enum btrfs_trans_state
{
41 TRANS_STATE_COMMIT_PREP
,
42 TRANS_STATE_COMMIT_START
,
43 TRANS_STATE_COMMIT_DOING
,
44 TRANS_STATE_UNBLOCKED
,
45 TRANS_STATE_SUPER_COMMITTED
,
46 TRANS_STATE_COMPLETED
,
50 #define BTRFS_TRANS_HAVE_FREE_BGS 0
51 #define BTRFS_TRANS_DIRTY_BG_RUN 1
52 #define BTRFS_TRANS_CACHE_ENOSPC 2
54 struct btrfs_transaction
{
57 * total external writers(USERSPACE/START/ATTACH) in this
58 * transaction, it must be zero before the transaction is
61 atomic_t num_extwriters
;
63 * total writers in this transaction, it must be zero before the
71 /* Be protected by fs_info->trans_lock when we want to change it. */
72 enum btrfs_trans_state state
;
74 struct list_head list
;
75 struct extent_io_tree dirty_pages
;
77 wait_queue_head_t writer_wait
;
78 wait_queue_head_t commit_wait
;
79 struct list_head pending_snapshots
;
80 struct list_head dev_update_list
;
81 struct list_head switch_commits
;
82 struct list_head dirty_bgs
;
85 * There is no explicit lock which protects io_bgs, rather its
86 * consistency is implied by the fact that all the sites which modify
87 * it do so under some form of transaction critical section, namely:
89 * - btrfs_start_dirty_block_groups - This function can only ever be
90 * run by one of the transaction committers. Refer to
91 * BTRFS_TRANS_DIRTY_BG_RUN usage in btrfs_commit_transaction
93 * - btrfs_write_dirty_blockgroups - this is called by
94 * commit_cowonly_roots from transaction critical section
95 * (TRANS_STATE_COMMIT_DOING)
97 * - btrfs_cleanup_dirty_bgs - called on transaction abort
99 struct list_head io_bgs
;
100 struct list_head dropped_roots
;
101 struct extent_io_tree pinned_extents
;
104 * we need to make sure block group deletion doesn't race with
105 * free space cache writeout. This mutex keeps them from stomping
108 struct mutex cache_write_mutex
;
109 spinlock_t dirty_bgs_lock
;
110 /* Protected by spin lock fs_info->unused_bgs_lock. */
111 struct list_head deleted_bgs
;
112 spinlock_t dropped_roots_lock
;
113 struct btrfs_delayed_ref_root delayed_refs
;
114 struct btrfs_fs_info
*fs_info
;
117 * Number of ordered extents the transaction must wait for before
118 * committing. These are ordered extents started by a fast fsync.
120 atomic_t pending_ordered
;
121 wait_queue_head_t pending_wait
;
125 ENUM_BIT(__TRANS_FREEZABLE
),
126 ENUM_BIT(__TRANS_START
),
127 ENUM_BIT(__TRANS_ATTACH
),
128 ENUM_BIT(__TRANS_JOIN
),
129 ENUM_BIT(__TRANS_JOIN_NOLOCK
),
130 ENUM_BIT(__TRANS_DUMMY
),
131 ENUM_BIT(__TRANS_JOIN_NOSTART
),
134 #define TRANS_START (__TRANS_START | __TRANS_FREEZABLE)
135 #define TRANS_ATTACH (__TRANS_ATTACH)
136 #define TRANS_JOIN (__TRANS_JOIN | __TRANS_FREEZABLE)
137 #define TRANS_JOIN_NOLOCK (__TRANS_JOIN_NOLOCK)
138 #define TRANS_JOIN_NOSTART (__TRANS_JOIN_NOSTART)
140 #define TRANS_EXTWRITERS (__TRANS_START | __TRANS_ATTACH)
142 struct btrfs_trans_handle
{
145 u64 delayed_refs_bytes_reserved
;
146 u64 chunk_bytes_reserved
;
147 unsigned long delayed_ref_updates
;
148 unsigned long delayed_ref_csum_deletions
;
149 struct btrfs_transaction
*transaction
;
150 struct btrfs_block_rsv
*block_rsv
;
151 struct btrfs_block_rsv
*orig_rsv
;
152 /* Set by a task that wants to create a snapshot. */
153 struct btrfs_pending_snapshot
*pending_snapshot
;
154 refcount_t use_count
;
157 * Error code of transaction abort, set outside of locks and must use
158 * the READ_ONCE/WRITE_ONCE access
162 bool allocating_chunk
;
166 struct btrfs_fs_info
*fs_info
;
167 struct list_head new_bgs
;
168 struct btrfs_block_rsv delayed_rsv
;
172 * The abort status can be changed between calls and is not protected by locks.
173 * This accepts btrfs_transaction and btrfs_trans_handle as types. Once it's
174 * set to a non-zero value it does not change, so the macro should be in checks
175 * but is not necessary for further reads of the value.
177 #define TRANS_ABORTED(trans) (unlikely(READ_ONCE((trans)->aborted)))
179 struct btrfs_pending_snapshot
{
180 struct dentry
*dentry
;
181 struct btrfs_inode
*dir
;
182 struct btrfs_root
*root
;
183 struct btrfs_root_item
*root_item
;
184 struct btrfs_root
*snap
;
185 struct btrfs_qgroup_inherit
*inherit
;
186 struct btrfs_path
*path
;
187 /* block reservation for the operation */
188 struct btrfs_block_rsv block_rsv
;
189 /* extra metadata reservation for relocation */
191 /* Preallocated anonymous block device number */
194 struct list_head list
;
197 static inline void btrfs_set_inode_last_trans(struct btrfs_trans_handle
*trans
,
198 struct btrfs_inode
*inode
)
200 spin_lock(&inode
->lock
);
201 inode
->last_trans
= trans
->transaction
->transid
;
202 inode
->last_sub_trans
= btrfs_get_root_log_transid(inode
->root
);
203 inode
->last_log_commit
= inode
->last_sub_trans
- 1;
204 spin_unlock(&inode
->lock
);
208 * Make qgroup codes to skip given qgroupid, means the old/new_roots for
209 * qgroup won't contain the qgroupid in it.
211 static inline void btrfs_set_skip_qgroup(struct btrfs_trans_handle
*trans
,
214 struct btrfs_delayed_ref_root
*delayed_refs
;
216 delayed_refs
= &trans
->transaction
->delayed_refs
;
217 WARN_ON(delayed_refs
->qgroup_to_skip
);
218 delayed_refs
->qgroup_to_skip
= qgroupid
;
221 static inline void btrfs_clear_skip_qgroup(struct btrfs_trans_handle
*trans
)
223 struct btrfs_delayed_ref_root
*delayed_refs
;
225 delayed_refs
= &trans
->transaction
->delayed_refs
;
226 WARN_ON(!delayed_refs
->qgroup_to_skip
);
227 delayed_refs
->qgroup_to_skip
= 0;
230 bool __cold
abort_should_print_stack(int error
);
233 * Call btrfs_abort_transaction as early as possible when an error condition is
234 * detected, that way the exact stack trace is reported for some errors.
236 #define btrfs_abort_transaction(trans, error) \
238 bool __first = false; \
239 /* Report first abort since mount */ \
240 if (!test_and_set_bit(BTRFS_FS_STATE_TRANS_ABORTED, \
241 &((trans)->fs_info->fs_state))) { \
243 if (WARN(abort_should_print_stack(error), \
245 "BTRFS: Transaction aborted (error %d)\n", \
247 /* Stack trace printed. */ \
249 btrfs_err((trans)->fs_info, \
250 "Transaction aborted (error %d)", \
254 __btrfs_abort_transaction((trans), __func__, \
255 __LINE__, (error), __first); \
258 int btrfs_end_transaction(struct btrfs_trans_handle
*trans
);
259 struct btrfs_trans_handle
*btrfs_start_transaction(struct btrfs_root
*root
,
260 unsigned int num_items
);
261 struct btrfs_trans_handle
*btrfs_start_transaction_fallback_global_rsv(
262 struct btrfs_root
*root
,
263 unsigned int num_items
);
264 struct btrfs_trans_handle
*btrfs_join_transaction(struct btrfs_root
*root
);
265 struct btrfs_trans_handle
*btrfs_join_transaction_spacecache(struct btrfs_root
*root
);
266 struct btrfs_trans_handle
*btrfs_join_transaction_nostart(struct btrfs_root
*root
);
267 struct btrfs_trans_handle
*btrfs_attach_transaction(struct btrfs_root
*root
);
268 struct btrfs_trans_handle
*btrfs_attach_transaction_barrier(
269 struct btrfs_root
*root
);
270 int btrfs_wait_for_commit(struct btrfs_fs_info
*fs_info
, u64 transid
);
272 void btrfs_add_dead_root(struct btrfs_root
*root
);
273 void btrfs_maybe_wake_unfinished_drop(struct btrfs_fs_info
*fs_info
);
274 int btrfs_clean_one_deleted_snapshot(struct btrfs_fs_info
*fs_info
);
275 int btrfs_commit_transaction(struct btrfs_trans_handle
*trans
);
276 void btrfs_commit_transaction_async(struct btrfs_trans_handle
*trans
);
277 int btrfs_commit_current_transaction(struct btrfs_root
*root
);
278 int btrfs_end_transaction_throttle(struct btrfs_trans_handle
*trans
);
279 bool btrfs_should_end_transaction(struct btrfs_trans_handle
*trans
);
280 void btrfs_throttle(struct btrfs_fs_info
*fs_info
);
281 int btrfs_record_root_in_trans(struct btrfs_trans_handle
*trans
,
282 struct btrfs_root
*root
);
283 int btrfs_write_marked_extents(struct btrfs_fs_info
*fs_info
,
284 struct extent_io_tree
*dirty_pages
, int mark
);
285 int btrfs_wait_tree_log_extents(struct btrfs_root
*root
, int mark
);
286 int btrfs_transaction_blocked(struct btrfs_fs_info
*info
);
287 void btrfs_put_transaction(struct btrfs_transaction
*transaction
);
288 void btrfs_add_dropped_root(struct btrfs_trans_handle
*trans
,
289 struct btrfs_root
*root
);
290 void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle
*trans
);
291 void __cold
__btrfs_abort_transaction(struct btrfs_trans_handle
*trans
,
292 const char *function
,
293 unsigned int line
, int error
, bool first_hit
);
295 int __init
btrfs_transaction_init(void);
296 void __cold
btrfs_transaction_exit(void);