edf53112a6f209c0a0fc4669debcd53c82428f2e
[sfrench/cifs-2.6.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
22 #include <linux/refcount.h>
23 #include "btrfs_inode.h"
24 #include "delayed-ref.h"
25 #include "ctree.h"
26
27 enum btrfs_trans_state {
28         TRANS_STATE_RUNNING             = 0,
29         TRANS_STATE_BLOCKED             = 1,
30         TRANS_STATE_COMMIT_START        = 2,
31         TRANS_STATE_COMMIT_DOING        = 3,
32         TRANS_STATE_UNBLOCKED           = 4,
33         TRANS_STATE_COMPLETED           = 5,
34         TRANS_STATE_MAX                 = 6,
35 };
36
37 #define BTRFS_TRANS_HAVE_FREE_BGS       0
38 #define BTRFS_TRANS_DIRTY_BG_RUN        1
39 #define BTRFS_TRANS_CACHE_ENOSPC        2
40
41 struct btrfs_transaction {
42         u64 transid;
43         /*
44          * total external writers(USERSPACE/START/ATTACH) in this
45          * transaction, it must be zero before the transaction is
46          * being committed
47          */
48         atomic_t num_extwriters;
49         /*
50          * total writers in this transaction, it must be zero before the
51          * transaction can end
52          */
53         atomic_t num_writers;
54         refcount_t use_count;
55         atomic_t pending_ordered;
56
57         unsigned long flags;
58
59         /* Be protected by fs_info->trans_lock when we want to change it. */
60         enum btrfs_trans_state state;
61         struct list_head list;
62         struct extent_io_tree dirty_pages;
63         unsigned long start_time;
64         wait_queue_head_t writer_wait;
65         wait_queue_head_t commit_wait;
66         wait_queue_head_t pending_wait;
67         struct list_head pending_snapshots;
68         struct list_head pending_chunks;
69         struct list_head switch_commits;
70         struct list_head dirty_bgs;
71         struct list_head io_bgs;
72         struct list_head dropped_roots;
73         u64 num_dirty_bgs;
74
75         /*
76          * we need to make sure block group deletion doesn't race with
77          * free space cache writeout.  This mutex keeps them from stomping
78          * on each other
79          */
80         struct mutex cache_write_mutex;
81         spinlock_t dirty_bgs_lock;
82         /* Protected by spin lock fs_info->unused_bgs_lock. */
83         struct list_head deleted_bgs;
84         spinlock_t dropped_roots_lock;
85         struct btrfs_delayed_ref_root delayed_refs;
86         int aborted;
87         struct btrfs_fs_info *fs_info;
88 };
89
90 #define __TRANS_FREEZABLE       (1U << 0)
91
92 #define __TRANS_USERSPACE       (1U << 8)
93 #define __TRANS_START           (1U << 9)
94 #define __TRANS_ATTACH          (1U << 10)
95 #define __TRANS_JOIN            (1U << 11)
96 #define __TRANS_JOIN_NOLOCK     (1U << 12)
97 #define __TRANS_DUMMY           (1U << 13)
98
99 #define TRANS_USERSPACE         (__TRANS_USERSPACE | __TRANS_FREEZABLE)
100 #define TRANS_START             (__TRANS_START | __TRANS_FREEZABLE)
101 #define TRANS_ATTACH            (__TRANS_ATTACH)
102 #define TRANS_JOIN              (__TRANS_JOIN | __TRANS_FREEZABLE)
103 #define TRANS_JOIN_NOLOCK       (__TRANS_JOIN_NOLOCK)
104
105 #define TRANS_EXTWRITERS        (__TRANS_USERSPACE | __TRANS_START |    \
106                                  __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         u64 qgroup_reserved;
143         /* extra metadata reservation for relocation */
144         int error;
145         bool readonly;
146         struct list_head list;
147 };
148
149 static inline void btrfs_set_inode_last_trans(struct btrfs_trans_handle *trans,
150                                               struct inode *inode)
151 {
152         spin_lock(&BTRFS_I(inode)->lock);
153         BTRFS_I(inode)->last_trans = trans->transaction->transid;
154         BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
155         BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit;
156         spin_unlock(&BTRFS_I(inode)->lock);
157 }
158
159 /*
160  * Make qgroup codes to skip given qgroupid, means the old/new_roots for
161  * qgroup won't contain the qgroupid in it.
162  */
163 static inline void btrfs_set_skip_qgroup(struct btrfs_trans_handle *trans,
164                                          u64 qgroupid)
165 {
166         struct btrfs_delayed_ref_root *delayed_refs;
167
168         delayed_refs = &trans->transaction->delayed_refs;
169         WARN_ON(delayed_refs->qgroup_to_skip);
170         delayed_refs->qgroup_to_skip = qgroupid;
171 }
172
173 static inline void btrfs_clear_skip_qgroup(struct btrfs_trans_handle *trans)
174 {
175         struct btrfs_delayed_ref_root *delayed_refs;
176
177         delayed_refs = &trans->transaction->delayed_refs;
178         WARN_ON(!delayed_refs->qgroup_to_skip);
179         delayed_refs->qgroup_to_skip = 0;
180 }
181
182 int btrfs_end_transaction(struct btrfs_trans_handle *trans);
183 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
184                                                    unsigned int num_items);
185 struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv(
186                                         struct btrfs_root *root,
187                                         unsigned int num_items,
188                                         int min_factor);
189 struct btrfs_trans_handle *btrfs_start_transaction_lflush(
190                                         struct btrfs_root *root,
191                                         unsigned int num_items);
192 struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root);
193 struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root);
194 struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root);
195 struct btrfs_trans_handle *btrfs_attach_transaction_barrier(
196                                         struct btrfs_root *root);
197 struct btrfs_trans_handle *btrfs_start_ioctl_transaction(struct btrfs_root *root);
198 int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid);
199
200 void btrfs_add_dead_root(struct btrfs_root *root);
201 int btrfs_defrag_root(struct btrfs_root *root);
202 int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root);
203 int btrfs_commit_transaction(struct btrfs_trans_handle *trans);
204 int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
205                                    int wait_for_unblock);
206 int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans);
207 int btrfs_should_end_transaction(struct btrfs_trans_handle *trans);
208 void btrfs_throttle(struct btrfs_fs_info *fs_info);
209 int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
210                                 struct btrfs_root *root);
211 int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info,
212                                 struct extent_io_tree *dirty_pages, int mark);
213 int btrfs_wait_extents(struct btrfs_fs_info *fs_info,
214                        struct extent_io_tree *dirty_pages);
215 int btrfs_wait_tree_log_extents(struct btrfs_root *root, int mark);
216 int btrfs_transaction_blocked(struct btrfs_fs_info *info);
217 int btrfs_transaction_in_commit(struct btrfs_fs_info *info);
218 void btrfs_put_transaction(struct btrfs_transaction *transaction);
219 void btrfs_apply_pending_changes(struct btrfs_fs_info *fs_info);
220 void btrfs_add_dropped_root(struct btrfs_trans_handle *trans,
221                             struct btrfs_root *root);
222 #endif