xref: /openbmc/linux/fs/btrfs/ordered-data.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_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 struct btrfs_ordered_sum {
30 	/* bytenr is the start of this extent on disk */
31 	u64 bytenr;
32 
33 	/*
34 	 * this is the length in bytes covered by the sums array below.
35 	 */
36 	int len;
37 	struct list_head list;
38 	/* last field is a variable length array of csums */
39 	u32 sums[];
40 };
41 
42 /*
43  * bits for the flags field:
44  *
45  * BTRFS_ORDERED_IO_DONE is set when all of the blocks are written.
46  * It is used to make sure metadata is inserted into the tree only once
47  * per extent.
48  *
49  * BTRFS_ORDERED_COMPLETE is set when the extent is removed from the
50  * rbtree, just before waking any waiters.  It is used to indicate the
51  * IO is done and any metadata is inserted into the tree.
52  */
53 #define BTRFS_ORDERED_IO_DONE 0 /* set when all the pages are written */
54 
55 #define BTRFS_ORDERED_COMPLETE 1 /* set when removed from the tree */
56 
57 #define BTRFS_ORDERED_NOCOW 2 /* set when we want to write in place */
58 
59 #define BTRFS_ORDERED_COMPRESSED 3 /* writing a zlib compressed extent */
60 
61 #define BTRFS_ORDERED_PREALLOC 4 /* set when writing to prealloced extent */
62 
63 #define BTRFS_ORDERED_DIRECT 5 /* set when we're doing DIO with this extent */
64 
65 #define BTRFS_ORDERED_IOERR 6 /* We had an io error when writing this out */
66 
67 #define BTRFS_ORDERED_UPDATED_ISIZE 7 /* indicates whether this ordered extent
68 				       * has done its due diligence in updating
69 				       * the isize. */
70 #define BTRFS_ORDERED_LOGGED_CSUM 8 /* We've logged the csums on this ordered
71 				       ordered extent */
72 #define BTRFS_ORDERED_TRUNCATED 9 /* Set when we have to truncate an extent */
73 
74 #define BTRFS_ORDERED_LOGGED 10 /* Set when we've waited on this ordered extent
75 				 * in the logging code. */
76 struct btrfs_ordered_extent {
77 	/* logical offset in the file */
78 	u64 file_offset;
79 
80 	/* disk byte number */
81 	u64 start;
82 
83 	/* ram length of the extent in bytes */
84 	u64 len;
85 
86 	/* extent length on disk */
87 	u64 disk_len;
88 
89 	/* number of bytes that still need writing */
90 	u64 bytes_left;
91 
92 	/* number of bytes that still need csumming */
93 	u64 csum_bytes_left;
94 
95 	/*
96 	 * the end of the ordered extent which is behind it but
97 	 * didn't update disk_i_size. Please see the comment of
98 	 * btrfs_ordered_update_i_size();
99 	 */
100 	u64 outstanding_isize;
101 
102 	/*
103 	 * If we get truncated we need to adjust the file extent we enter for
104 	 * this ordered extent so that we do not expose stale data.
105 	 */
106 	u64 truncated_len;
107 
108 	/* flags (described above) */
109 	unsigned long flags;
110 
111 	/* compression algorithm */
112 	int compress_type;
113 
114 	/* reference count */
115 	atomic_t refs;
116 
117 	/* the inode we belong to */
118 	struct inode *inode;
119 
120 	/* list of checksums for insertion when the extent io is done */
121 	struct list_head list;
122 
123 	/* If we need to wait on this to be done */
124 	struct list_head log_list;
125 
126 	/* If the transaction needs to wait on this ordered extent */
127 	struct list_head trans_list;
128 
129 	/* used to wait for the BTRFS_ORDERED_COMPLETE bit */
130 	wait_queue_head_t wait;
131 
132 	/* our friendly rbtree entry */
133 	struct rb_node rb_node;
134 
135 	/* a per root list of all the pending ordered extents */
136 	struct list_head root_extent_list;
137 
138 	struct btrfs_work work;
139 
140 	struct completion completion;
141 	struct btrfs_work flush_work;
142 	struct list_head work_list;
143 };
144 
145 /*
146  * calculates the total size you need to allocate for an ordered sum
147  * structure spanning 'bytes' in the file
148  */
149 static inline int btrfs_ordered_sum_size(struct btrfs_root *root,
150 					 unsigned long bytes)
151 {
152 	int num_sectors = (int)DIV_ROUND_UP(bytes, root->sectorsize);
153 	return sizeof(struct btrfs_ordered_sum) + num_sectors * sizeof(u32);
154 }
155 
156 static inline void
157 btrfs_ordered_inode_tree_init(struct btrfs_ordered_inode_tree *t)
158 {
159 	spin_lock_init(&t->lock);
160 	t->tree = RB_ROOT;
161 	t->last = NULL;
162 }
163 
164 void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry);
165 void btrfs_remove_ordered_extent(struct inode *inode,
166 				struct btrfs_ordered_extent *entry);
167 int btrfs_dec_test_ordered_pending(struct inode *inode,
168 				   struct btrfs_ordered_extent **cached,
169 				   u64 file_offset, u64 io_size, int uptodate);
170 int btrfs_dec_test_first_ordered_pending(struct inode *inode,
171 				   struct btrfs_ordered_extent **cached,
172 				   u64 *file_offset, u64 io_size,
173 				   int uptodate);
174 int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
175 			     u64 start, u64 len, u64 disk_len, int type);
176 int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
177 				 u64 start, u64 len, u64 disk_len, int type);
178 int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
179 				      u64 start, u64 len, u64 disk_len,
180 				      int type, int compress_type);
181 void btrfs_add_ordered_sum(struct inode *inode,
182 			   struct btrfs_ordered_extent *entry,
183 			   struct btrfs_ordered_sum *sum);
184 struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
185 							 u64 file_offset);
186 void btrfs_start_ordered_extent(struct inode *inode,
187 				struct btrfs_ordered_extent *entry, int wait);
188 int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len);
189 struct btrfs_ordered_extent *
190 btrfs_lookup_first_ordered_extent(struct inode * inode, u64 file_offset);
191 struct btrfs_ordered_extent *btrfs_lookup_ordered_range(struct inode *inode,
192 							u64 file_offset,
193 							u64 len);
194 int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
195 				struct btrfs_ordered_extent *ordered);
196 int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
197 			   u32 *sum, int len);
198 int btrfs_wait_ordered_extents(struct btrfs_root *root, int nr);
199 void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, int nr);
200 void btrfs_get_logged_extents(struct inode *inode,
201 			      struct list_head *logged_list,
202 			      const loff_t start,
203 			      const loff_t end);
204 void btrfs_put_logged_extents(struct list_head *logged_list);
205 void btrfs_submit_logged_extents(struct list_head *logged_list,
206 				 struct btrfs_root *log);
207 void btrfs_wait_logged_extents(struct btrfs_trans_handle *trans,
208 			       struct btrfs_root *log, u64 transid);
209 void btrfs_free_logged_extents(struct btrfs_root *log, u64 transid);
210 int __init ordered_data_init(void);
211 void ordered_data_exit(void);
212 #endif
213