xref: /openbmc/linux/fs/btrfs/ordered-data.h (revision 0c874100)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 2007 Oracle.  All rights reserved.
4  */
5 
6 #ifndef BTRFS_ORDERED_DATA_H
7 #define BTRFS_ORDERED_DATA_H
8 
9 /* one of these per inode */
10 struct btrfs_ordered_inode_tree {
11 	spinlock_t lock;
12 	struct rb_root tree;
13 	struct rb_node *last;
14 };
15 
16 struct btrfs_ordered_sum {
17 	/* bytenr is the start of this extent on disk */
18 	u64 bytenr;
19 
20 	/*
21 	 * this is the length in bytes covered by the sums array below.
22 	 */
23 	int len;
24 	struct list_head list;
25 	/* last field is a variable length array of csums */
26 	u32 sums[];
27 };
28 
29 /*
30  * bits for the flags field:
31  *
32  * BTRFS_ORDERED_IO_DONE is set when all of the blocks are written.
33  * It is used to make sure metadata is inserted into the tree only once
34  * per extent.
35  *
36  * BTRFS_ORDERED_COMPLETE is set when the extent is removed from the
37  * rbtree, just before waking any waiters.  It is used to indicate the
38  * IO is done and any metadata is inserted into the tree.
39  */
40 #define BTRFS_ORDERED_IO_DONE 0 /* set when all the pages are written */
41 
42 #define BTRFS_ORDERED_COMPLETE 1 /* set when removed from the tree */
43 
44 #define BTRFS_ORDERED_NOCOW 2 /* set when we want to write in place */
45 
46 #define BTRFS_ORDERED_COMPRESSED 3 /* writing a zlib compressed extent */
47 
48 #define BTRFS_ORDERED_PREALLOC 4 /* set when writing to preallocated extent */
49 
50 #define BTRFS_ORDERED_DIRECT 5 /* set when we're doing DIO with this extent */
51 
52 #define BTRFS_ORDERED_IOERR 6 /* We had an io error when writing this out */
53 
54 #define BTRFS_ORDERED_UPDATED_ISIZE 7 /* indicates whether this ordered extent
55 				       * has done its due diligence in updating
56 				       * the isize. */
57 #define BTRFS_ORDERED_TRUNCATED 8 /* Set when we have to truncate an extent */
58 
59 #define BTRFS_ORDERED_PENDING 9 /* We are waiting for this ordered extent to
60 				  * complete in the current transaction. */
61 #define BTRFS_ORDERED_REGULAR 10 /* Regular IO for COW */
62 
63 struct btrfs_ordered_extent {
64 	/* logical offset in the file */
65 	u64 file_offset;
66 
67 	/* disk byte number */
68 	u64 start;
69 
70 	/* ram length of the extent in bytes */
71 	u64 len;
72 
73 	/* extent length on disk */
74 	u64 disk_len;
75 
76 	/* number of bytes that still need writing */
77 	u64 bytes_left;
78 
79 	/*
80 	 * the end of the ordered extent which is behind it but
81 	 * didn't update disk_i_size. Please see the comment of
82 	 * btrfs_ordered_update_i_size();
83 	 */
84 	u64 outstanding_isize;
85 
86 	/*
87 	 * If we get truncated we need to adjust the file extent we enter for
88 	 * this ordered extent so that we do not expose stale data.
89 	 */
90 	u64 truncated_len;
91 
92 	/* flags (described above) */
93 	unsigned long flags;
94 
95 	/* compression algorithm */
96 	int compress_type;
97 
98 	/* reference count */
99 	refcount_t refs;
100 
101 	/* the inode we belong to */
102 	struct inode *inode;
103 
104 	/* list of checksums for insertion when the extent io is done */
105 	struct list_head list;
106 
107 	/* If we need to wait on this to be done */
108 	struct list_head log_list;
109 
110 	/* If the transaction needs to wait on this ordered extent */
111 	struct list_head trans_list;
112 
113 	/* used to wait for the BTRFS_ORDERED_COMPLETE bit */
114 	wait_queue_head_t wait;
115 
116 	/* our friendly rbtree entry */
117 	struct rb_node rb_node;
118 
119 	/* a per root list of all the pending ordered extents */
120 	struct list_head root_extent_list;
121 
122 	struct btrfs_work work;
123 
124 	struct completion completion;
125 	struct btrfs_work flush_work;
126 	struct list_head work_list;
127 };
128 
129 /*
130  * calculates the total size you need to allocate for an ordered sum
131  * structure spanning 'bytes' in the file
132  */
133 static inline int btrfs_ordered_sum_size(struct btrfs_fs_info *fs_info,
134 					 unsigned long bytes)
135 {
136 	int num_sectors = (int)DIV_ROUND_UP(bytes, fs_info->sectorsize);
137 	int csum_size = btrfs_super_csum_size(fs_info->super_copy);
138 
139 	return sizeof(struct btrfs_ordered_sum) + num_sectors * csum_size;
140 }
141 
142 static inline void
143 btrfs_ordered_inode_tree_init(struct btrfs_ordered_inode_tree *t)
144 {
145 	spin_lock_init(&t->lock);
146 	t->tree = RB_ROOT;
147 	t->last = NULL;
148 }
149 
150 void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry);
151 void btrfs_remove_ordered_extent(struct inode *inode,
152 				struct btrfs_ordered_extent *entry);
153 int btrfs_dec_test_ordered_pending(struct inode *inode,
154 				   struct btrfs_ordered_extent **cached,
155 				   u64 file_offset, u64 io_size, int uptodate);
156 int btrfs_dec_test_first_ordered_pending(struct inode *inode,
157 				   struct btrfs_ordered_extent **cached,
158 				   u64 *file_offset, u64 io_size,
159 				   int uptodate);
160 int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
161 			     u64 start, u64 len, u64 disk_len, int type);
162 int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
163 				 u64 start, u64 len, u64 disk_len, int type);
164 int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
165 				      u64 start, u64 len, u64 disk_len,
166 				      int type, int compress_type);
167 void btrfs_add_ordered_sum(struct inode *inode,
168 			   struct btrfs_ordered_extent *entry,
169 			   struct btrfs_ordered_sum *sum);
170 struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
171 							 u64 file_offset);
172 void btrfs_start_ordered_extent(struct inode *inode,
173 				struct btrfs_ordered_extent *entry, int wait);
174 int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len);
175 struct btrfs_ordered_extent *
176 btrfs_lookup_first_ordered_extent(struct inode * inode, u64 file_offset);
177 struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
178 		struct btrfs_inode *inode,
179 		u64 file_offset,
180 		u64 len);
181 int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
182 				struct btrfs_ordered_extent *ordered);
183 int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
184 			   u32 *sum, int len);
185 u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
186 			       const u64 range_start, const u64 range_len);
187 u64 btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
188 			      const u64 range_start, const u64 range_len);
189 int __init ordered_data_init(void);
190 void __cold ordered_data_exit(void);
191 
192 #endif
193