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