xref: /openbmc/linux/fs/btrfs/transaction.h (revision 827634ad)
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 struct btrfs_transaction {
36 	u64 transid;
37 	/*
38 	 * total external writers(USERSPACE/START/ATTACH) in this
39 	 * transaction, it must be zero before the transaction is
40 	 * being committed
41 	 */
42 	atomic_t num_extwriters;
43 	/*
44 	 * total writers in this transaction, it must be zero before the
45 	 * transaction can end
46 	 */
47 	atomic_t num_writers;
48 	atomic_t use_count;
49 
50 	/*
51 	 * true if there is free bgs operations in this transaction
52 	 */
53 	int have_free_bgs;
54 
55 	/* Be protected by fs_info->trans_lock when we want to change it. */
56 	enum btrfs_trans_state state;
57 	struct list_head list;
58 	struct extent_io_tree dirty_pages;
59 	unsigned long start_time;
60 	wait_queue_head_t writer_wait;
61 	wait_queue_head_t commit_wait;
62 	struct list_head pending_snapshots;
63 	struct list_head pending_chunks;
64 	struct list_head pending_ordered;
65 	struct list_head switch_commits;
66 	struct list_head dirty_bgs;
67 	struct list_head io_bgs;
68 	u64 num_dirty_bgs;
69 
70 	/*
71 	 * we need to make sure block group deletion doesn't race with
72 	 * free space cache writeout.  This mutex keeps them from stomping
73 	 * on each other
74 	 */
75 	struct mutex cache_write_mutex;
76 	spinlock_t dirty_bgs_lock;
77 	struct btrfs_delayed_ref_root delayed_refs;
78 	int aborted;
79 	int dirty_bg_run;
80 };
81 
82 #define __TRANS_FREEZABLE	(1U << 0)
83 
84 #define __TRANS_USERSPACE	(1U << 8)
85 #define __TRANS_START		(1U << 9)
86 #define __TRANS_ATTACH		(1U << 10)
87 #define __TRANS_JOIN		(1U << 11)
88 #define __TRANS_JOIN_NOLOCK	(1U << 12)
89 #define __TRANS_DUMMY		(1U << 13)
90 
91 #define TRANS_USERSPACE		(__TRANS_USERSPACE | __TRANS_FREEZABLE)
92 #define TRANS_START		(__TRANS_START | __TRANS_FREEZABLE)
93 #define TRANS_ATTACH		(__TRANS_ATTACH)
94 #define TRANS_JOIN		(__TRANS_JOIN | __TRANS_FREEZABLE)
95 #define TRANS_JOIN_NOLOCK	(__TRANS_JOIN_NOLOCK)
96 
97 #define TRANS_EXTWRITERS	(__TRANS_USERSPACE | __TRANS_START |	\
98 				 __TRANS_ATTACH)
99 
100 #define BTRFS_SEND_TRANS_STUB	((void *)1)
101 
102 struct btrfs_trans_handle {
103 	u64 transid;
104 	u64 bytes_reserved;
105 	u64 qgroup_reserved;
106 	unsigned long use_count;
107 	unsigned long blocks_reserved;
108 	unsigned long blocks_used;
109 	unsigned long delayed_ref_updates;
110 	struct btrfs_transaction *transaction;
111 	struct btrfs_block_rsv *block_rsv;
112 	struct btrfs_block_rsv *orig_rsv;
113 	short aborted;
114 	short adding_csums;
115 	bool allocating_chunk;
116 	bool reloc_reserved;
117 	bool sync;
118 	unsigned int type;
119 	/*
120 	 * this root is only needed to validate that the root passed to
121 	 * start_transaction is the same as the one passed to end_transaction.
122 	 * Subvolume quota depends on this
123 	 */
124 	struct btrfs_root *root;
125 	struct seq_list delayed_ref_elem;
126 	struct list_head ordered;
127 	struct list_head qgroup_ref_list;
128 	struct list_head new_bgs;
129 };
130 
131 struct btrfs_pending_snapshot {
132 	struct dentry *dentry;
133 	struct inode *dir;
134 	struct btrfs_root *root;
135 	struct btrfs_root *snap;
136 	struct btrfs_qgroup_inherit *inherit;
137 	/* block reservation for the operation */
138 	struct btrfs_block_rsv block_rsv;
139 	u64 qgroup_reserved;
140 	/* extra metadata reseration for relocation */
141 	int error;
142 	bool readonly;
143 	struct list_head list;
144 };
145 
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 int btrfs_end_transaction(struct btrfs_trans_handle *trans,
157 			  struct btrfs_root *root);
158 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
159 						   int num_items);
160 struct btrfs_trans_handle *btrfs_start_transaction_lflush(
161 					struct btrfs_root *root, int num_items);
162 struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root);
163 struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root);
164 struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root);
165 struct btrfs_trans_handle *btrfs_attach_transaction_barrier(
166 					struct btrfs_root *root);
167 struct btrfs_trans_handle *btrfs_start_ioctl_transaction(struct btrfs_root *root);
168 int btrfs_wait_for_commit(struct btrfs_root *root, u64 transid);
169 
170 void btrfs_add_dead_root(struct btrfs_root *root);
171 int btrfs_defrag_root(struct btrfs_root *root);
172 int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root);
173 int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
174 			     struct btrfs_root *root);
175 int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
176 				   struct btrfs_root *root,
177 				   int wait_for_unblock);
178 int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans,
179 				   struct btrfs_root *root);
180 int btrfs_should_end_transaction(struct btrfs_trans_handle *trans,
181 				 struct btrfs_root *root);
182 void btrfs_throttle(struct btrfs_root *root);
183 int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
184 				struct btrfs_root *root);
185 int btrfs_write_marked_extents(struct btrfs_root *root,
186 				struct extent_io_tree *dirty_pages, int mark);
187 int btrfs_wait_marked_extents(struct btrfs_root *root,
188 				struct extent_io_tree *dirty_pages, int mark);
189 int btrfs_transaction_blocked(struct btrfs_fs_info *info);
190 int btrfs_transaction_in_commit(struct btrfs_fs_info *info);
191 void btrfs_put_transaction(struct btrfs_transaction *transaction);
192 void btrfs_apply_pending_changes(struct btrfs_fs_info *fs_info);
193 
194 #endif
195