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_ORDERED_DATA__
20 #define __BTRFS_ORDERED_DATA__
21
22 /* one of these per inode */
23 struct btrfs_ordered_inode_tree {
24 struct mutex mutex;
25 struct rb_root tree;
26 struct rb_node *last;
27 };
28
29 /*
30 * these are used to collect checksums done just before bios submission.
31 * They are attached via a list into the ordered extent, and
32 * checksum items are inserted into the tree after all the blocks in
33 * the ordered extent are on disk
34 */
35 struct btrfs_sector_sum {
36 /* bytenr on disk */
37 u64 bytenr;
38 u32 sum;
39 };
40
41 struct btrfs_ordered_sum {
42 /* bytenr is the start of this extent on disk */
43 u64 bytenr;
44
45 /*
46 * this is the length in bytes covered by the sums array below.
47 */
48 unsigned long len;
49 struct list_head list;
50 /* last field is a variable length array of btrfs_sector_sums */
51 struct btrfs_sector_sum sums[];
52 };
53
54 /*
55 * bits for the flags field:
56 *
57 * BTRFS_ORDERED_IO_DONE is set when all of the blocks are written.
58 * It is used to make sure metadata is inserted into the tree only once
59 * per extent.
60 *
61 * BTRFS_ORDERED_COMPLETE is set when the extent is removed from the
62 * rbtree, just before waking any waiters. It is used to indicate the
63 * IO is done and any metadata is inserted into the tree.
64 */
65 #define BTRFS_ORDERED_IO_DONE 0 /* set when all the pages are written */
66
67 #define BTRFS_ORDERED_COMPLETE 1 /* set when removed from the tree */
68
69 #define BTRFS_ORDERED_NOCOW 2 /* set when we want to write in place */
70
71 #define BTRFS_ORDERED_COMPRESSED 3 /* writing a compressed extent */
72
73 #define BTRFS_ORDERED_PREALLOC 4 /* set when writing to prealloced extent */
74
75 struct btrfs_ordered_extent {
76 /* logical offset in the file */
77 u64 file_offset;
78
79 /* disk byte number */
80 u64 start;
81
82 /* ram length of the extent in bytes */
83 u64 len;
84
85 /* extent length on disk */
86 u64 disk_len;
87
88 /* flags (described above) */
89 unsigned long flags;
90
91 /* reference count */
92 atomic_t refs;
93
94 /* the inode we belong to */
95 struct inode *inode;
96
97 /* list of checksums for insertion when the extent io is done */
98 struct list_head list;
99
100 /* used to wait for the BTRFS_ORDERED_COMPLETE bit */
101 wait_queue_head_t wait;
102
103 /* our friendly rbtree entry */
104 struct rb_node rb_node;
105
106 /* a per root list of all the pending ordered extents */
107 struct list_head root_extent_list;
108 };
109
110
111 /*
112 * calculates the total size you need to allocate for an ordered sum
113 * structure spanning 'bytes' in the file
114 */
btrfs_ordered_sum_size(struct btrfs_root * root,unsigned long bytes)115 static inline int btrfs_ordered_sum_size(struct btrfs_root *root,
116 unsigned long bytes)
117 {
118 unsigned long num_sectors = (bytes + root->sectorsize - 1) /
119 root->sectorsize;
120 num_sectors++;
121 return sizeof(struct btrfs_ordered_sum) +
122 num_sectors * sizeof(struct btrfs_sector_sum);
123 }
124
125 static inline void
btrfs_ordered_inode_tree_init(struct btrfs_ordered_inode_tree * t)126 btrfs_ordered_inode_tree_init(struct btrfs_ordered_inode_tree *t)
127 {
128 mutex_init(&t->mutex);
129 t->tree.rb_node = NULL;
130 t->last = NULL;
131 }
132
133 int btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry);
134 int btrfs_remove_ordered_extent(struct inode *inode,
135 struct btrfs_ordered_extent *entry);
136 int btrfs_dec_test_ordered_pending(struct inode *inode,
137 u64 file_offset, u64 io_size);
138 int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
139 u64 start, u64 len, u64 disk_len, int tyep);
140 int btrfs_add_ordered_sum(struct inode *inode,
141 struct btrfs_ordered_extent *entry,
142 struct btrfs_ordered_sum *sum);
143 struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
144 u64 file_offset);
145 void btrfs_start_ordered_extent(struct inode *inode,
146 struct btrfs_ordered_extent *entry, int wait);
147 int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len);
148 struct btrfs_ordered_extent *
149 btrfs_lookup_first_ordered_extent(struct inode * inode, u64 file_offset);
150 int btrfs_ordered_update_i_size(struct inode *inode,
151 struct btrfs_ordered_extent *ordered);
152 int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr, u32 *sum);
153 int btrfs_wait_on_page_writeback_range(struct address_space *mapping,
154 pgoff_t start, pgoff_t end);
155 int btrfs_fdatawrite_range(struct address_space *mapping, loff_t start,
156 loff_t end, int sync_mode);
157 int btrfs_wait_ordered_extents(struct btrfs_root *root, int nocow_only);
158 #endif
159