Merge branch 'for-linus-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/mason...
[cascardo/linux.git] / fs / btrfs / transaction.h
1 /*
2  * Copyright (C) 2007 Oracle.  All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public
6  * License v2 as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
11  * General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public
14  * License along with this program; if not, write to the
15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16  * Boston, MA 021110-1307, USA.
17  */
18
19 #ifndef __BTRFS_TRANSACTION__
20 #define __BTRFS_TRANSACTION__
21 #include "btrfs_inode.h"
22 #include "delayed-ref.h"
23 #include "ctree.h"
24
25 enum btrfs_trans_state {
26         TRANS_STATE_RUNNING             = 0,
27         TRANS_STATE_BLOCKED             = 1,
28         TRANS_STATE_COMMIT_START        = 2,
29         TRANS_STATE_COMMIT_DOING        = 3,
30         TRANS_STATE_UNBLOCKED           = 4,
31         TRANS_STATE_COMPLETED           = 5,
32         TRANS_STATE_MAX                 = 6,
33 };
34
35 #define BTRFS_TRANS_HAVE_FREE_BGS       0
36 #define BTRFS_TRANS_DIRTY_BG_RUN        1
37 #define BTRFS_TRANS_CACHE_ENOSPC        2
38
39 struct btrfs_transaction {
40         u64 transid;
41         /*
42          * total external writers(USERSPACE/START/ATTACH) in this
43          * transaction, it must be zero before the transaction is
44          * being committed
45          */
46         atomic_t num_extwriters;
47         /*
48          * total writers in this transaction, it must be zero before the
49          * transaction can end
50          */
51         atomic_t num_writers;
52         atomic_t use_count;
53         atomic_t pending_ordered;
54
55         unsigned long flags;
56
57         /* Be protected by fs_info->trans_lock when we want to change it. */
58         enum btrfs_trans_state state;
59         struct list_head list;
60         struct extent_io_tree dirty_pages;
61         unsigned long start_time;
62         wait_queue_head_t writer_wait;
63         wait_queue_head_t commit_wait;
64         wait_queue_head_t pending_wait;
65         struct list_head pending_snapshots;
66         struct list_head pending_chunks;
67         struct list_head switch_commits;
68         struct list_head dirty_bgs;
69         struct list_head io_bgs;
70         struct list_head dropped_roots;
71         u64 num_dirty_bgs;
72
73         /*
74          * we need to make sure block group deletion doesn't race with
75          * free space cache writeout.  This mutex keeps them from stomping
76          * on each other
77          */
78         struct mutex cache_write_mutex;
79         spinlock_t dirty_bgs_lock;
80         /* Protected by spin lock fs_info->unused_bgs_lock. */
81         struct list_head deleted_bgs;
82         spinlock_t dropped_roots_lock;
83         struct btrfs_delayed_ref_root delayed_refs;
84         int aborted;
85         struct btrfs_fs_info *fs_info;
86 };
87
88 #define __TRANS_FREEZABLE       (1U << 0)
89
90 #define __TRANS_USERSPACE       (1U << 8)
91 #define __TRANS_START           (1U << 9)
92 #define __TRANS_ATTACH          (1U << 10)
93 #define __TRANS_JOIN            (1U << 11)
94 #define __TRANS_JOIN_NOLOCK     (1U << 12)
95 #define __TRANS_DUMMY           (1U << 13)
96
97 #define TRANS_USERSPACE         (__TRANS_USERSPACE | __TRANS_FREEZABLE)
98 #define TRANS_START             (__TRANS_START | __TRANS_FREEZABLE)
99 #define TRANS_ATTACH            (__TRANS_ATTACH)
100 #define TRANS_JOIN              (__TRANS_JOIN | __TRANS_FREEZABLE)
101 #define TRANS_JOIN_NOLOCK       (__TRANS_JOIN_NOLOCK)
102
103 #define TRANS_EXTWRITERS        (__TRANS_USERSPACE | __TRANS_START |    \
104                                  __TRANS_ATTACH)
105
106 #define BTRFS_SEND_TRANS_STUB   ((void *)1)
107
108 struct btrfs_trans_handle {
109         u64 transid;
110         u64 bytes_reserved;
111         u64 chunk_bytes_reserved;
112         unsigned long use_count;
113         unsigned long blocks_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         short aborted;
119         short adding_csums;
120         bool allocating_chunk;
121         bool can_flush_pending_bgs;
122         bool reloc_reserved;
123         bool sync;
124         bool dirty;
125         unsigned int type;
126         /*
127          * this root is only needed to validate that the root passed to
128          * start_transaction is the same as the one passed to end_transaction.
129          * Subvolume quota depends on this
130          */
131         struct btrfs_root *root;
132         struct btrfs_fs_info *fs_info;
133         struct seq_list delayed_ref_elem;
134         struct list_head qgroup_ref_list;
135         struct list_head new_bgs;
136 };
137
138 struct btrfs_pending_snapshot {
139         struct dentry *dentry;
140         struct inode *dir;
141         struct btrfs_root *root;
142         struct btrfs_root_item *root_item;
143         struct btrfs_root *snap;
144         struct btrfs_qgroup_inherit *inherit;
145         struct btrfs_path *path;
146         /* block reservation for the operation */
147         struct btrfs_block_rsv block_rsv;
148         u64 qgroup_reserved;
149         /* extra metadata reservation for relocation */
150         int error;
151         bool readonly;
152         struct list_head list;
153 };
154
155 static inline void btrfs_set_inode_last_trans(struct btrfs_trans_handle *trans,
156                                               struct inode *inode)
157 {
158         spin_lock(&BTRFS_I(inode)->lock);
159         BTRFS_I(inode)->last_trans = trans->transaction->transid;
160         BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
161         BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit;
162         spin_unlock(&BTRFS_I(inode)->lock);
163 }
164
165 /*
166  * Make qgroup codes to skip given qgroupid, means the old/new_roots for
167  * qgroup won't contain the qgroupid in it.
168  */
169 static inline void btrfs_set_skip_qgroup(struct btrfs_trans_handle *trans,
170                                          u64 qgroupid)
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 = qgroupid;
177 }
178
179 static inline void btrfs_clear_skip_qgroup(struct btrfs_trans_handle *trans)
180 {
181         struct btrfs_delayed_ref_root *delayed_refs;
182
183         delayed_refs = &trans->transaction->delayed_refs;
184         WARN_ON(!delayed_refs->qgroup_to_skip);
185         delayed_refs->qgroup_to_skip = 0;
186 }
187
188 int btrfs_end_transaction(struct btrfs_trans_handle *trans,
189                           struct btrfs_root *root);
190 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
191                                                    unsigned int num_items);
192 struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv(
193                                         struct btrfs_root *root,
194                                         unsigned int num_items,
195                                         int min_factor);
196 struct btrfs_trans_handle *btrfs_start_transaction_lflush(
197                                         struct btrfs_root *root,
198                                         unsigned int num_items);
199 struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root);
200 struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root);
201 struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root);
202 struct btrfs_trans_handle *btrfs_attach_transaction_barrier(
203                                         struct btrfs_root *root);
204 struct btrfs_trans_handle *btrfs_start_ioctl_transaction(struct btrfs_root *root);
205 int btrfs_wait_for_commit(struct btrfs_root *root, u64 transid);
206
207 void btrfs_add_dead_root(struct btrfs_root *root);
208 int btrfs_defrag_root(struct btrfs_root *root);
209 int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root);
210 int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
211                              struct btrfs_root *root);
212 int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
213                                    struct btrfs_root *root,
214                                    int wait_for_unblock);
215 int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans,
216                                    struct btrfs_root *root);
217 int btrfs_should_end_transaction(struct btrfs_trans_handle *trans,
218                                  struct btrfs_root *root);
219 void btrfs_throttle(struct btrfs_root *root);
220 int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
221                                 struct btrfs_root *root);
222 int btrfs_write_marked_extents(struct btrfs_root *root,
223                                 struct extent_io_tree *dirty_pages, int mark);
224 int btrfs_wait_marked_extents(struct btrfs_root *root,
225                                 struct extent_io_tree *dirty_pages, int mark);
226 int btrfs_transaction_blocked(struct btrfs_fs_info *info);
227 int btrfs_transaction_in_commit(struct btrfs_fs_info *info);
228 void btrfs_put_transaction(struct btrfs_transaction *transaction);
229 void btrfs_apply_pending_changes(struct btrfs_fs_info *fs_info);
230 void btrfs_add_dropped_root(struct btrfs_trans_handle *trans,
231                             struct btrfs_root *root);
232 #endif