summaryrefslogtreecommitdiff
path: root/fs/btrfs/ordered-data.h
blob: d61ea9c880a32719ed7e80a4b9a4aef011d07838 (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
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright (C) 2007 Oracle.  All rights reserved.
 */

#ifndef BTRFS_ORDERED_DATA_H
#define BTRFS_ORDERED_DATA_H

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

struct btrfs_ordered_sum {
	/* bytenr is the start of this extent on disk */
	u64 bytenr;

	/*
	 * this is the length in bytes covered by the sums array below.
	 */
	int len;
	struct list_head list;
	/* last field is a variable length array of csums */
	u8 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.
 */
enum {
	/* set when all the pages are written */
	BTRFS_ORDERED_IO_DONE,
	/* set when removed from the tree */
	BTRFS_ORDERED_COMPLETE,
	/* set when we want to write in place */
	BTRFS_ORDERED_NOCOW,
	/* writing a zlib compressed extent */
	BTRFS_ORDERED_COMPRESSED,
	/* set when writing to preallocated extent */
	BTRFS_ORDERED_PREALLOC,
	/* set when we're doing DIO with this extent */
	BTRFS_ORDERED_DIRECT,
	/* We had an io error when writing this out */
	BTRFS_ORDERED_IOERR,
	/* Set when we have to truncate an extent */
	BTRFS_ORDERED_TRUNCATED,
	/* Regular IO for COW */
	BTRFS_ORDERED_REGULAR,
};

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

	/*
	 * These fields directly correspond to the same fields in
	 * btrfs_file_extent_item.
	 */
	u64 disk_bytenr;
	u64 num_bytes;
	u64 disk_num_bytes;

	/* number of bytes that still need writing */
	u64 bytes_left;

	/*
	 * the end of the ordered extent which is behind it but
	 * didn't update disk_i_size. Please see the comment of
	 * btrfs_ordered_update_i_size();
	 */
	u64 outstanding_isize;

	/*
	 * If we get truncated we need to adjust the file extent we enter for
	 * this ordered extent so that we do not expose stale data.
	 */
	u64 truncated_len;

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

	/* compression algorithm */
	int compress_type;

	/* Qgroup reserved space */
	int qgroup_rsv;

	/* reference count */
	refcount_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;

	struct btrfs_work work;

	struct completion completion;
	struct btrfs_work flush_work;
	struct list_head work_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_fs_info *fs_info,
					 unsigned long bytes)
{
	int num_sectors = (int)DIV_ROUND_UP(bytes, fs_info->sectorsize);
	int csum_size = btrfs_super_csum_size(fs_info->super_copy);

	return sizeof(struct btrfs_ordered_sum) + num_sectors * csum_size;
}

static inline void
btrfs_ordered_inode_tree_init(struct btrfs_ordered_inode_tree *t)
{
	spin_lock_init(&t->lock);
	t->tree = RB_ROOT;
	t->last = NULL;
}

void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry);
void btrfs_remove_ordered_extent(struct inode *inode,
				struct btrfs_ordered_extent *entry);
int btrfs_dec_test_ordered_pending(struct inode *inode,
				   struct btrfs_ordered_extent **cached,
				   u64 file_offset, u64 io_size, int uptodate);
int btrfs_dec_test_first_ordered_pending(struct btrfs_inode *inode,
				   struct btrfs_ordered_extent **cached,
				   u64 *file_offset, u64 io_size,
				   int uptodate);
int btrfs_add_ordered_extent(struct btrfs_inode *inode, u64 file_offset,
			     u64 disk_bytenr, u64 num_bytes, u64 disk_num_bytes,
			     int type);
int btrfs_add_ordered_extent_dio(struct btrfs_inode *inode, u64 file_offset,
				 u64 disk_bytenr, u64 num_bytes,
				 u64 disk_num_bytes, int type);
int btrfs_add_ordered_extent_compress(struct btrfs_inode *inode, u64 file_offset,
				      u64 disk_bytenr, u64 num_bytes,
				      u64 disk_num_bytes, int type,
				      int compress_type);
void btrfs_add_ordered_sum(struct btrfs_ordered_extent *entry,
			   struct btrfs_ordered_sum *sum);
struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_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);
struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
		struct btrfs_inode *inode,
		u64 file_offset,
		u64 len);
int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
			   u8 *sum, int len);
u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
			       const u64 range_start, const u64 range_len);
void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
			      const u64 range_start, const u64 range_len);
void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start,
					u64 end,
					struct extent_state **cached_state);
int __init ordered_data_init(void);
void __cold ordered_data_exit(void);

#endif