1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6 #ifndef BTRFS_TRANSACTION_H
7 #define BTRFS_TRANSACTION_H
8
9 #include <linux/refcount.h>
10 #include "btrfs_inode.h"
11 #include "delayed-ref.h"
12 #include "ctree.h"
13
14 enum btrfs_trans_state {
15 TRANS_STATE_RUNNING = 0,
16 TRANS_STATE_BLOCKED = 1,
17 TRANS_STATE_COMMIT_START = 2,
18 TRANS_STATE_COMMIT_DOING = 3,
19 TRANS_STATE_UNBLOCKED = 4,
20 TRANS_STATE_COMPLETED = 5,
21 TRANS_STATE_MAX = 6,
22 };
23
24 #define BTRFS_TRANS_HAVE_FREE_BGS 0
25 #define BTRFS_TRANS_DIRTY_BG_RUN 1
26 #define BTRFS_TRANS_CACHE_ENOSPC 2
27
28 struct btrfs_transaction {
29 u64 transid;
30 /*
31 * total external writers(USERSPACE/START/ATTACH) in this
32 * transaction, it must be zero before the transaction is
33 * being committed
34 */
35 atomic_t num_extwriters;
36 /*
37 * total writers in this transaction, it must be zero before the
38 * transaction can end
39 */
40 atomic_t num_writers;
41 refcount_t use_count;
42 atomic_t pending_ordered;
43
44 unsigned long flags;
45
46 /* Be protected by fs_info->trans_lock when we want to change it. */
47 enum btrfs_trans_state state;
48 int aborted;
49 struct list_head list;
50 struct extent_io_tree dirty_pages;
51 time64_t start_time;
52 wait_queue_head_t writer_wait;
53 wait_queue_head_t commit_wait;
54 wait_queue_head_t pending_wait;
55 struct list_head pending_snapshots;
56 struct list_head pending_chunks;
57 struct list_head switch_commits;
58 struct list_head dirty_bgs;
59
60 /*
61 * There is no explicit lock which protects io_bgs, rather its
62 * consistency is implied by the fact that all the sites which modify
63 * it do so under some form of transaction critical section, namely:
64 *
65 * - btrfs_start_dirty_block_groups - This function can only ever be
66 * run by one of the transaction committers. Refer to
67 * BTRFS_TRANS_DIRTY_BG_RUN usage in btrfs_commit_transaction
68 *
69 * - btrfs_write_dirty_blockgroups - this is called by
70 * commit_cowonly_roots from transaction critical section
71 * (TRANS_STATE_COMMIT_DOING)
72 *
73 * - btrfs_cleanup_dirty_bgs - called on transaction abort
74 */
75 struct list_head io_bgs;
76 struct list_head dropped_roots;
77
78 /*
79 * we need to make sure block group deletion doesn't race with
80 * free space cache writeout. This mutex keeps them from stomping
81 * on each other
82 */
83 struct mutex cache_write_mutex;
84 spinlock_t dirty_bgs_lock;
85 unsigned int num_dirty_bgs;
86 /* Protected by spin lock fs_info->unused_bgs_lock. */
87 struct list_head deleted_bgs;
88 spinlock_t dropped_roots_lock;
89 struct btrfs_delayed_ref_root delayed_refs;
90 struct btrfs_fs_info *fs_info;
91 };
92
93 #define __TRANS_FREEZABLE (1U << 0)
94
95 #define __TRANS_START (1U << 9)
96 #define __TRANS_ATTACH (1U << 10)
97 #define __TRANS_JOIN (1U << 11)
98 #define __TRANS_JOIN_NOLOCK (1U << 12)
99 #define __TRANS_DUMMY (1U << 13)
100
101 #define TRANS_START (__TRANS_START | __TRANS_FREEZABLE)
102 #define TRANS_ATTACH (__TRANS_ATTACH)
103 #define TRANS_JOIN (__TRANS_JOIN | __TRANS_FREEZABLE)
104 #define TRANS_JOIN_NOLOCK (__TRANS_JOIN_NOLOCK)
105
106 #define TRANS_EXTWRITERS (__TRANS_START | __TRANS_ATTACH)
107
108 #define BTRFS_SEND_TRANS_STUB ((void *)1)
109
110 struct btrfs_trans_handle {
111 u64 transid;
112 u64 bytes_reserved;
113 u64 chunk_bytes_reserved;
114 unsigned long delayed_ref_updates;
115 struct btrfs_transaction *transaction;
116 struct btrfs_block_rsv *block_rsv;
117 struct btrfs_block_rsv *orig_rsv;
118 refcount_t use_count;
119 unsigned int type;
120 short aborted;
121 bool adding_csums;
122 bool allocating_chunk;
123 bool can_flush_pending_bgs;
124 bool reloc_reserved;
125 bool sync;
126 bool dirty;
127 struct btrfs_root *root;
128 struct btrfs_fs_info *fs_info;
129 struct list_head new_bgs;
130 };
131
132 struct btrfs_pending_snapshot {
133 struct dentry *dentry;
134 struct inode *dir;
135 struct btrfs_root *root;
136 struct btrfs_root_item *root_item;
137 struct btrfs_root *snap;
138 struct btrfs_qgroup_inherit *inherit;
139 struct btrfs_path *path;
140 /* block reservation for the operation */
141 struct btrfs_block_rsv block_rsv;
142 /* extra metadata reservation for relocation */
143 int error;
144 bool readonly;
145 struct list_head list;
146 };
147
btrfs_set_inode_last_trans(struct btrfs_trans_handle * trans,struct inode * inode)148 static inline void btrfs_set_inode_last_trans(struct btrfs_trans_handle *trans,
149 struct inode *inode)
150 {
151 spin_lock(&BTRFS_I(inode)->lock);
152 BTRFS_I(inode)->last_trans = trans->transaction->transid;
153 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
154 BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit;
155 spin_unlock(&BTRFS_I(inode)->lock);
156 }
157
158 /*
159 * Make qgroup codes to skip given qgroupid, means the old/new_roots for
160 * qgroup won't contain the qgroupid in it.
161 */
btrfs_set_skip_qgroup(struct btrfs_trans_handle * trans,u64 qgroupid)162 static inline void btrfs_set_skip_qgroup(struct btrfs_trans_handle *trans,
163 u64 qgroupid)
164 {
165 struct btrfs_delayed_ref_root *delayed_refs;
166
167 delayed_refs = &trans->transaction->delayed_refs;
168 WARN_ON(delayed_refs->qgroup_to_skip);
169 delayed_refs->qgroup_to_skip = qgroupid;
170 }
171
btrfs_clear_skip_qgroup(struct btrfs_trans_handle * trans)172 static inline void btrfs_clear_skip_qgroup(struct btrfs_trans_handle *trans)
173 {
174 struct btrfs_delayed_ref_root *delayed_refs;
175
176 delayed_refs = &trans->transaction->delayed_refs;
177 WARN_ON(!delayed_refs->qgroup_to_skip);
178 delayed_refs->qgroup_to_skip = 0;
179 }
180
181 int btrfs_end_transaction(struct btrfs_trans_handle *trans);
182 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
183 unsigned int num_items);
184 struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv(
185 struct btrfs_root *root,
186 unsigned int num_items,
187 int min_factor);
188 struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root);
189 struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root);
190 struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root);
191 struct btrfs_trans_handle *btrfs_attach_transaction_barrier(
192 struct btrfs_root *root);
193 int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid);
194
195 void btrfs_add_dead_root(struct btrfs_root *root);
196 int btrfs_defrag_root(struct btrfs_root *root);
197 int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root);
198 int btrfs_commit_transaction(struct btrfs_trans_handle *trans);
199 int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
200 int wait_for_unblock);
201
202 /*
203 * Try to commit transaction asynchronously, so this is safe to call
204 * even holding a spinlock.
205 *
206 * It's done by informing transaction_kthread to commit transaction without
207 * waiting for commit interval.
208 */
btrfs_commit_transaction_locksafe(struct btrfs_fs_info * fs_info)209 static inline void btrfs_commit_transaction_locksafe(
210 struct btrfs_fs_info *fs_info)
211 {
212 set_bit(BTRFS_FS_NEED_ASYNC_COMMIT, &fs_info->flags);
213 wake_up_process(fs_info->transaction_kthread);
214 }
215 int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans);
216 int btrfs_should_end_transaction(struct btrfs_trans_handle *trans);
217 void btrfs_throttle(struct btrfs_fs_info *fs_info);
218 int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
219 struct btrfs_root *root);
220 int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info,
221 struct extent_io_tree *dirty_pages, int mark);
222 int btrfs_wait_extents(struct btrfs_fs_info *fs_info,
223 struct extent_io_tree *dirty_pages);
224 int btrfs_wait_tree_log_extents(struct btrfs_root *root, int mark);
225 int btrfs_transaction_blocked(struct btrfs_fs_info *info);
226 int btrfs_transaction_in_commit(struct btrfs_fs_info *info);
227 void btrfs_put_transaction(struct btrfs_transaction *transaction);
228 void btrfs_apply_pending_changes(struct btrfs_fs_info *fs_info);
229 void btrfs_add_dropped_root(struct btrfs_trans_handle *trans,
230 struct btrfs_root *root);
231
232 #endif
233
