summaryrefslogtreecommitdiff
path: root/fs/btrfs/ordered-data.h
blob: 260bf95dfe0cd4960b36f07e96fee1ea356092d4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
/*
 * Copyright (C) 2007 Oracle.  All rights reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public
 * License v2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 021110-1307, USA.
 */

#ifndef __BTRFS_ORDERED_DATA__
#define __BTRFS_ORDERED_DATA__

/* one of these per inode */
struct btrfs_ordered_inode_tree {
	struct mutex mutex;
	struct rb_root tree;
	struct rb_node *last;
};

/*
 * these are used to collect checksums done just before bios submission.
 * They are attached via a list into the ordered extent, and
 * checksum items are inserted into the tree after all the blocks in
 * the ordered extent are on disk
 */
struct btrfs_sector_sum {
	u64 offset;
	u32 sum;
};

struct btrfs_ordered_sum {
	u64 file_offset;
	/*
	 * this is the length in bytes covered by the sums array below.
	 * But, the sums array may not be contiguous in the file.
	 */
	unsigned long len;
	struct list_head list;
	/* last field is a variable length array of btrfs_sector_sums */
	struct btrfs_sector_sum sums[];
};

/*
 * bits for the flags field:
 *
 * BTRFS_ORDERED_IO_DONE is set when all of the blocks are written.
 * It is used to make sure metadata is inserted into the tree only once
 * per extent.
 *
 * BTRFS_ORDERED_COMPLETE is set when the extent is removed from the
 * rbtree, just before waking any waiters.  It is used to indicate the
 * IO is done and any metadata is inserted into the tree.
 */
#define BTRFS_ORDERED_IO_DONE 0 /* set when all the pages are written */

#define BTRFS_ORDERED_COMPLETE 1 /* set when removed from the tree */

#define BTRFS_ORDERED_NOCOW 2 /* set when we want to write in place */

#define BTRFS_ORDERED_COMPRESSED 3 /* writing a compressed extent */

#define BTRFS_ORDERED_PREALLOC 4 /* set when writing to prealloced extent */

struct btrfs_ordered_extent {
	/* logical offset in the file */
	u64 file_offset;

	/* disk byte number */
	u64 start;

	/* ram length of the extent in bytes */
	u64 len;

	/* extent length on disk */
	u64 disk_len;

	/* flags (described above) */
	unsigned long flags;

	/* reference count */
	atomic_t refs;

	/* the inode we belong to */
	struct inode *inode;

	/* list of checksums for insertion when the extent io is done */
	struct list_head list;

	/* used to wait for the BTRFS_ORDERED_COMPLETE bit */
	wait_queue_head_t wait;

	/* our friendly rbtree entry */
	struct rb_node rb_node;

	/* a per root list of all the pending ordered extents */
	struct list_head root_extent_list;
};


/*
 * calculates the total size you need to allocate for an ordered sum
 * structure spanning 'bytes' in the file
 */
static inline int btrfs_ordered_sum_size(struct btrfs_root *root,
					 unsigned long bytes)
{
	unsigned long num_sectors = (bytes + root->sectorsize - 1) /
		root->sectorsize;
	num_sectors++;
	return sizeof(struct btrfs_ordered_sum) +
		num_sectors * sizeof(struct btrfs_sector_sum);
}

static inline void
btrfs_ordered_inode_tree_init(struct btrfs_ordered_inode_tree *t)
{
	mutex_init(&t->mutex);
	t->tree.rb_node = NULL;
	t->last = NULL;
}

int btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry);
int btrfs_remove_ordered_extent(struct inode *inode,
				struct btrfs_ordered_extent *entry);
int btrfs_dec_test_ordered_pending(struct inode *inode,
				       u64 file_offset, u64 io_size);
int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
			     u64 start, u64 len, u64 disk_len, int tyep);
int btrfs_add_ordered_sum(struct inode *inode,
			  struct btrfs_ordered_extent *entry,
			  struct btrfs_ordered_sum *sum);
struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
							 u64 file_offset);
void btrfs_start_ordered_extent(struct inode *inode,
				struct btrfs_ordered_extent *entry, int wait);
int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len);
struct btrfs_ordered_extent *
btrfs_lookup_first_ordered_extent(struct inode * inode, u64 file_offset);
int btrfs_ordered_update_i_size(struct inode *inode,
				struct btrfs_ordered_extent *ordered);
int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u32 *sum);
int btrfs_wait_on_page_writeback_range(struct address_space *mapping,
				       pgoff_t start, pgoff_t end);
int btrfs_fdatawrite_range(struct address_space *mapping, loff_t start,
			   loff_t end, int sync_mode);
int btrfs_wait_ordered_extents(struct btrfs_root *root, int nocow_only);
#endif