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/refcount.h>
10 #include "btrfs_inode.h"
11 #include "delayed-ref.h"
15 /* Radix-tree tag for roots that are part of the trasaction. */
16 #define BTRFS_ROOT_TRANS_TAG 0
18 enum btrfs_trans_state {
20 TRANS_STATE_COMMIT_PREP,
21 TRANS_STATE_COMMIT_START,
22 TRANS_STATE_COMMIT_DOING,
23 TRANS_STATE_UNBLOCKED,
24 TRANS_STATE_SUPER_COMMITTED,
25 TRANS_STATE_COMPLETED,
29 #define BTRFS_TRANS_HAVE_FREE_BGS 0
30 #define BTRFS_TRANS_DIRTY_BG_RUN 1
31 #define BTRFS_TRANS_CACHE_ENOSPC 2
33 struct btrfs_transaction {
36 * total external writers(USERSPACE/START/ATTACH) in this
37 * transaction, it must be zero before the transaction is
40 atomic_t num_extwriters;
42 * total writers in this transaction, it must be zero before the
50 /* Be protected by fs_info->trans_lock when we want to change it. */
51 enum btrfs_trans_state state;
53 struct list_head list;
54 struct extent_io_tree dirty_pages;
56 wait_queue_head_t writer_wait;
57 wait_queue_head_t commit_wait;
58 struct list_head pending_snapshots;
59 struct list_head dev_update_list;
60 struct list_head switch_commits;
61 struct list_head dirty_bgs;
64 * There is no explicit lock which protects io_bgs, rather its
65 * consistency is implied by the fact that all the sites which modify
66 * it do so under some form of transaction critical section, namely:
68 * - btrfs_start_dirty_block_groups - This function can only ever be
69 * run by one of the transaction committers. Refer to
70 * BTRFS_TRANS_DIRTY_BG_RUN usage in btrfs_commit_transaction
72 * - btrfs_write_dirty_blockgroups - this is called by
73 * commit_cowonly_roots from transaction critical section
74 * (TRANS_STATE_COMMIT_DOING)
76 * - btrfs_cleanup_dirty_bgs - called on transaction abort
78 struct list_head io_bgs;
79 struct list_head dropped_roots;
80 struct extent_io_tree pinned_extents;
83 * we need to make sure block group deletion doesn't race with
84 * free space cache writeout. This mutex keeps them from stomping
87 struct mutex cache_write_mutex;
88 spinlock_t dirty_bgs_lock;
89 /* Protected by spin lock fs_info->unused_bgs_lock. */
90 struct list_head deleted_bgs;
91 spinlock_t dropped_roots_lock;
92 struct btrfs_delayed_ref_root delayed_refs;
93 struct btrfs_fs_info *fs_info;
96 * Number of ordered extents the transaction must wait for before
97 * committing. These are ordered extents started by a fast fsync.
99 atomic_t pending_ordered;
100 wait_queue_head_t pending_wait;
104 ENUM_BIT(__TRANS_FREEZABLE),
105 ENUM_BIT(__TRANS_START),
106 ENUM_BIT(__TRANS_ATTACH),
107 ENUM_BIT(__TRANS_JOIN),
108 ENUM_BIT(__TRANS_JOIN_NOLOCK),
109 ENUM_BIT(__TRANS_DUMMY),
110 ENUM_BIT(__TRANS_JOIN_NOSTART),
113 #define TRANS_START (__TRANS_START | __TRANS_FREEZABLE)
114 #define TRANS_ATTACH (__TRANS_ATTACH)
115 #define TRANS_JOIN (__TRANS_JOIN | __TRANS_FREEZABLE)
116 #define TRANS_JOIN_NOLOCK (__TRANS_JOIN_NOLOCK)
117 #define TRANS_JOIN_NOSTART (__TRANS_JOIN_NOSTART)
119 #define TRANS_EXTWRITERS (__TRANS_START | __TRANS_ATTACH)
121 struct btrfs_trans_handle {
124 u64 delayed_refs_bytes_reserved;
125 u64 chunk_bytes_reserved;
126 unsigned long delayed_ref_updates;
127 unsigned long delayed_ref_csum_deletions;
128 struct btrfs_transaction *transaction;
129 struct btrfs_block_rsv *block_rsv;
130 struct btrfs_block_rsv *orig_rsv;
131 /* Set by a task that wants to create a snapshot. */
132 struct btrfs_pending_snapshot *pending_snapshot;
133 refcount_t use_count;
136 * Error code of transaction abort, set outside of locks and must use
137 * the READ_ONCE/WRITE_ONCE access
141 bool allocating_chunk;
145 struct btrfs_fs_info *fs_info;
146 struct list_head new_bgs;
147 struct btrfs_block_rsv delayed_rsv;
151 * The abort status can be changed between calls and is not protected by locks.
152 * This accepts btrfs_transaction and btrfs_trans_handle as types. Once it's
153 * set to a non-zero value it does not change, so the macro should be in checks
154 * but is not necessary for further reads of the value.
156 #define TRANS_ABORTED(trans) (unlikely(READ_ONCE((trans)->aborted)))
158 struct btrfs_pending_snapshot {
159 struct dentry *dentry;
161 struct btrfs_root *root;
162 struct btrfs_root_item *root_item;
163 struct btrfs_root *snap;
164 struct btrfs_qgroup_inherit *inherit;
165 struct btrfs_path *path;
166 /* block reservation for the operation */
167 struct btrfs_block_rsv block_rsv;
168 /* extra metadata reservation for relocation */
170 /* Preallocated anonymous block device number */
173 struct list_head list;
176 static inline void btrfs_set_inode_last_trans(struct btrfs_trans_handle *trans,
177 struct btrfs_inode *inode)
179 spin_lock(&inode->lock);
180 inode->last_trans = trans->transaction->transid;
181 inode->last_sub_trans = btrfs_get_root_log_transid(inode->root);
182 inode->last_log_commit = inode->last_sub_trans - 1;
183 spin_unlock(&inode->lock);
187 * Make qgroup codes to skip given qgroupid, means the old/new_roots for
188 * qgroup won't contain the qgroupid in it.
190 static inline void btrfs_set_skip_qgroup(struct btrfs_trans_handle *trans,
193 struct btrfs_delayed_ref_root *delayed_refs;
195 delayed_refs = &trans->transaction->delayed_refs;
196 WARN_ON(delayed_refs->qgroup_to_skip);
197 delayed_refs->qgroup_to_skip = qgroupid;
200 static inline void btrfs_clear_skip_qgroup(struct btrfs_trans_handle *trans)
202 struct btrfs_delayed_ref_root *delayed_refs;
204 delayed_refs = &trans->transaction->delayed_refs;
205 WARN_ON(!delayed_refs->qgroup_to_skip);
206 delayed_refs->qgroup_to_skip = 0;
209 bool __cold abort_should_print_stack(int error);
212 * Call btrfs_abort_transaction as early as possible when an error condition is
213 * detected, that way the exact stack trace is reported for some errors.
215 #define btrfs_abort_transaction(trans, error) \
217 bool first = false; \
218 /* Report first abort since mount */ \
219 if (!test_and_set_bit(BTRFS_FS_STATE_TRANS_ABORTED, \
220 &((trans)->fs_info->fs_state))) { \
222 if (WARN(abort_should_print_stack(error), \
224 "BTRFS: Transaction aborted (error %d)\n", \
226 /* Stack trace printed. */ \
228 btrfs_err((trans)->fs_info, \
229 "Transaction aborted (error %d)", \
233 __btrfs_abort_transaction((trans), __func__, \
234 __LINE__, (error), first); \
237 int btrfs_end_transaction(struct btrfs_trans_handle *trans);
238 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
239 unsigned int num_items);
240 struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv(
241 struct btrfs_root *root,
242 unsigned int num_items);
243 struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root);
244 struct btrfs_trans_handle *btrfs_join_transaction_spacecache(struct btrfs_root *root);
245 struct btrfs_trans_handle *btrfs_join_transaction_nostart(struct btrfs_root *root);
246 struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root);
247 struct btrfs_trans_handle *btrfs_attach_transaction_barrier(
248 struct btrfs_root *root);
249 int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid);
251 void btrfs_add_dead_root(struct btrfs_root *root);
252 void btrfs_maybe_wake_unfinished_drop(struct btrfs_fs_info *fs_info);
253 int btrfs_clean_one_deleted_snapshot(struct btrfs_fs_info *fs_info);
254 int btrfs_commit_transaction(struct btrfs_trans_handle *trans);
255 void btrfs_commit_transaction_async(struct btrfs_trans_handle *trans);
256 int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans);
257 bool btrfs_should_end_transaction(struct btrfs_trans_handle *trans);
258 void btrfs_throttle(struct btrfs_fs_info *fs_info);
259 int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
260 struct btrfs_root *root);
261 int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info,
262 struct extent_io_tree *dirty_pages, int mark);
263 int btrfs_wait_tree_log_extents(struct btrfs_root *root, int mark);
264 int btrfs_transaction_blocked(struct btrfs_fs_info *info);
265 int btrfs_transaction_in_commit(struct btrfs_fs_info *info);
266 void btrfs_put_transaction(struct btrfs_transaction *transaction);
267 void btrfs_add_dropped_root(struct btrfs_trans_handle *trans,
268 struct btrfs_root *root);
269 void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans);
270 void __cold __btrfs_abort_transaction(struct btrfs_trans_handle *trans,
271 const char *function,
272 unsigned int line, int error, bool first_hit);
274 int __init btrfs_transaction_init(void);
275 void __cold btrfs_transaction_exit(void);