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 spinlock_t lock;
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 zlib compressed extent */
72
73 #define BTRFS_ORDERED_PREALLOC 4 /* set when writing to prealloced extent */
74
75 #define BTRFS_ORDERED_DIRECT 5 /* set when we're doing DIO with this extent */
76
77 struct btrfs_ordered_extent {
78 /* logical offset in the file */
79 u64 file_offset;
80
81 /* disk byte number */
82 u64 start;
83
84 /* ram length of the extent in bytes */
85 u64 len;
86
87 /* extent length on disk */
88 u64 disk_len;
89
90 /* number of bytes that still need writing */
91 u64 bytes_left;
92
93 /* flags (described above) */
94 unsigned long flags;
95
96 /* compression algorithm */
97 int compress_type;
98
99 /* reference count */
100 atomic_t refs;
101
102 /* the inode we belong to */
103 struct inode *inode;
104
105 /* list of checksums for insertion when the extent io is done */
106 struct list_head list;
107
108 /* used to wait for the BTRFS_ORDERED_COMPLETE bit */
109 wait_queue_head_t wait;
110
111 /* our friendly rbtree entry */
112 struct rb_node rb_node;
113
114 /* a per root list of all the pending ordered extents */
115 struct list_head root_extent_list;
116 };
117
118
119 /*
120 * calculates the total size you need to allocate for an ordered sum
121 * structure spanning 'bytes' in the file
122 */
btrfs_ordered_sum_size(struct btrfs_root * root,unsigned long bytes)123 static inline int btrfs_ordered_sum_size(struct btrfs_root *root,
124 unsigned long bytes)
125 {
126 unsigned long num_sectors = (bytes + root->sectorsize - 1) /
127 root->sectorsize;
128 num_sectors++;
129 return sizeof(struct btrfs_ordered_sum) +
130 num_sectors * sizeof(struct btrfs_sector_sum);
131 }
132
133 static inline void
btrfs_ordered_inode_tree_init(struct btrfs_ordered_inode_tree * t)134 btrfs_ordered_inode_tree_init(struct btrfs_ordered_inode_tree *t)
135 {
136 spin_lock_init(&t->lock);
137 t->tree = RB_ROOT;
138 t->last = NULL;
139 }
140
141 void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry);
142 void btrfs_remove_ordered_extent(struct inode *inode,
143 struct btrfs_ordered_extent *entry);
144 int btrfs_dec_test_ordered_pending(struct inode *inode,
145 struct btrfs_ordered_extent **cached,
146 u64 file_offset, u64 io_size);
147 int btrfs_dec_test_first_ordered_pending(struct inode *inode,
148 struct btrfs_ordered_extent **cached,
149 u64 *file_offset, u64 io_size);
150 int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
151 u64 start, u64 len, u64 disk_len, int type);
152 int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
153 u64 start, u64 len, u64 disk_len, int type);
154 int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
155 u64 start, u64 len, u64 disk_len,
156 int type, int compress_type);
157 void btrfs_add_ordered_sum(struct inode *inode,
158 struct btrfs_ordered_extent *entry,
159 struct btrfs_ordered_sum *sum);
160 struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
161 u64 file_offset);
162 void btrfs_start_ordered_extent(struct inode *inode,
163 struct btrfs_ordered_extent *entry, int wait);
164 void btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len);
165 struct btrfs_ordered_extent *
166 btrfs_lookup_first_ordered_extent(struct inode * inode, u64 file_offset);
167 struct btrfs_ordered_extent *btrfs_lookup_ordered_range(struct inode *inode,
168 u64 file_offset,
169 u64 len);
170 int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
171 struct btrfs_ordered_extent *ordered);
172 int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr, u32 *sum);
173 void btrfs_run_ordered_operations(struct btrfs_root *root, int wait);
174 void btrfs_add_ordered_operation(struct btrfs_trans_handle *trans,
175 struct btrfs_root *root,
176 struct inode *inode);
177 void btrfs_wait_ordered_extents(struct btrfs_root *root,
178 int nocow_only, int delay_iput);
179 #endif
180