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Linux kernel mirror (for testing)
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2
3#ifndef BTRFS_EXTENT_IO_H
4#define BTRFS_EXTENT_IO_H
5
6#include <linux/rbtree.h>
7#include <linux/refcount.h>
8#include "ulist.h"
9
10/*
11 * flags for bio submission. The high bits indicate the compression
12 * type for this bio
13 */
14#define EXTENT_BIO_COMPRESSED 1
15#define EXTENT_BIO_FLAG_SHIFT 16
16
17enum {
18 EXTENT_BUFFER_UPTODATE,
19 EXTENT_BUFFER_DIRTY,
20 EXTENT_BUFFER_CORRUPT,
21 /* this got triggered by readahead */
22 EXTENT_BUFFER_READAHEAD,
23 EXTENT_BUFFER_TREE_REF,
24 EXTENT_BUFFER_STALE,
25 EXTENT_BUFFER_WRITEBACK,
26 /* read IO error */
27 EXTENT_BUFFER_READ_ERR,
28 EXTENT_BUFFER_UNMAPPED,
29 EXTENT_BUFFER_IN_TREE,
30 /* write IO error */
31 EXTENT_BUFFER_WRITE_ERR,
32};
33
34/* these are flags for __process_pages_contig */
35#define PAGE_UNLOCK (1 << 0)
36#define PAGE_CLEAR_DIRTY (1 << 1)
37#define PAGE_SET_WRITEBACK (1 << 2)
38#define PAGE_END_WRITEBACK (1 << 3)
39#define PAGE_SET_PRIVATE2 (1 << 4)
40#define PAGE_SET_ERROR (1 << 5)
41#define PAGE_LOCK (1 << 6)
42
43/*
44 * page->private values. Every page that is controlled by the extent
45 * map has page->private set to one.
46 */
47#define EXTENT_PAGE_PRIVATE 1
48
49/*
50 * The extent buffer bitmap operations are done with byte granularity instead of
51 * word granularity for two reasons:
52 * 1. The bitmaps must be little-endian on disk.
53 * 2. Bitmap items are not guaranteed to be aligned to a word and therefore a
54 * single word in a bitmap may straddle two pages in the extent buffer.
55 */
56#define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE)
57#define BYTE_MASK ((1 << BITS_PER_BYTE) - 1)
58#define BITMAP_FIRST_BYTE_MASK(start) \
59 ((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK)
60#define BITMAP_LAST_BYTE_MASK(nbits) \
61 (BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1)))
62
63struct btrfs_root;
64struct btrfs_inode;
65struct btrfs_io_bio;
66struct io_failure_record;
67struct extent_io_tree;
68
69typedef blk_status_t (extent_submit_bio_start_t)(void *private_data,
70 struct bio *bio, u64 bio_offset);
71
72struct extent_io_ops {
73 /*
74 * The following callbacks must be always defined, the function
75 * pointer will be called unconditionally.
76 */
77 blk_status_t (*submit_bio_hook)(struct inode *inode, struct bio *bio,
78 int mirror_num, unsigned long bio_flags);
79 int (*readpage_end_io_hook)(struct btrfs_io_bio *io_bio, u64 phy_offset,
80 struct page *page, u64 start, u64 end,
81 int mirror);
82};
83
84
85#define INLINE_EXTENT_BUFFER_PAGES 16
86#define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_SIZE)
87struct extent_buffer {
88 u64 start;
89 unsigned long len;
90 unsigned long bflags;
91 struct btrfs_fs_info *fs_info;
92 spinlock_t refs_lock;
93 atomic_t refs;
94 atomic_t io_pages;
95 int read_mirror;
96 struct rcu_head rcu_head;
97 pid_t lock_owner;
98
99 int blocking_writers;
100 atomic_t blocking_readers;
101 bool lock_nested;
102 /* >= 0 if eb belongs to a log tree, -1 otherwise */
103 short log_index;
104
105 /* protects write locks */
106 rwlock_t lock;
107
108 /* readers use lock_wq while they wait for the write
109 * lock holders to unlock
110 */
111 wait_queue_head_t write_lock_wq;
112
113 /* writers use read_lock_wq while they wait for readers
114 * to unlock
115 */
116 wait_queue_head_t read_lock_wq;
117 struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
118#ifdef CONFIG_BTRFS_DEBUG
119 int spinning_writers;
120 atomic_t spinning_readers;
121 atomic_t read_locks;
122 int write_locks;
123 struct list_head leak_list;
124#endif
125};
126
127/*
128 * Structure to record how many bytes and which ranges are set/cleared
129 */
130struct extent_changeset {
131 /* How many bytes are set/cleared in this operation */
132 unsigned int bytes_changed;
133
134 /* Changed ranges */
135 struct ulist range_changed;
136};
137
138static inline void extent_changeset_init(struct extent_changeset *changeset)
139{
140 changeset->bytes_changed = 0;
141 ulist_init(&changeset->range_changed);
142}
143
144static inline struct extent_changeset *extent_changeset_alloc(void)
145{
146 struct extent_changeset *ret;
147
148 ret = kmalloc(sizeof(*ret), GFP_KERNEL);
149 if (!ret)
150 return NULL;
151
152 extent_changeset_init(ret);
153 return ret;
154}
155
156static inline void extent_changeset_release(struct extent_changeset *changeset)
157{
158 if (!changeset)
159 return;
160 changeset->bytes_changed = 0;
161 ulist_release(&changeset->range_changed);
162}
163
164static inline void extent_changeset_free(struct extent_changeset *changeset)
165{
166 if (!changeset)
167 return;
168 extent_changeset_release(changeset);
169 kfree(changeset);
170}
171
172static inline void extent_set_compress_type(unsigned long *bio_flags,
173 int compress_type)
174{
175 *bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT;
176}
177
178static inline int extent_compress_type(unsigned long bio_flags)
179{
180 return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
181}
182
183struct extent_map_tree;
184
185typedef struct extent_map *(get_extent_t)(struct btrfs_inode *inode,
186 struct page *page,
187 size_t pg_offset,
188 u64 start, u64 len,
189 int create);
190
191int try_release_extent_mapping(struct page *page, gfp_t mask);
192int try_release_extent_buffer(struct page *page);
193
194int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
195 get_extent_t *get_extent, int mirror_num);
196int extent_write_full_page(struct page *page, struct writeback_control *wbc);
197int extent_write_locked_range(struct inode *inode, u64 start, u64 end,
198 int mode);
199int extent_writepages(struct address_space *mapping,
200 struct writeback_control *wbc);
201int btree_write_cache_pages(struct address_space *mapping,
202 struct writeback_control *wbc);
203int extent_readpages(struct address_space *mapping, struct list_head *pages,
204 unsigned nr_pages);
205int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
206 __u64 start, __u64 len);
207void set_page_extent_mapped(struct page *page);
208
209struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
210 u64 start);
211struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
212 u64 start, unsigned long len);
213struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
214 u64 start);
215struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
216struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
217 u64 start);
218void free_extent_buffer(struct extent_buffer *eb);
219void free_extent_buffer_stale(struct extent_buffer *eb);
220#define WAIT_NONE 0
221#define WAIT_COMPLETE 1
222#define WAIT_PAGE_LOCK 2
223int read_extent_buffer_pages(struct extent_buffer *eb, int wait,
224 int mirror_num);
225void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
226
227static inline int num_extent_pages(const struct extent_buffer *eb)
228{
229 return (round_up(eb->start + eb->len, PAGE_SIZE) >> PAGE_SHIFT) -
230 (eb->start >> PAGE_SHIFT);
231}
232
233static inline int extent_buffer_uptodate(struct extent_buffer *eb)
234{
235 return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
236}
237
238int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv,
239 unsigned long start, unsigned long len);
240void read_extent_buffer(const struct extent_buffer *eb, void *dst,
241 unsigned long start,
242 unsigned long len);
243int read_extent_buffer_to_user(const struct extent_buffer *eb,
244 void __user *dst, unsigned long start,
245 unsigned long len);
246void write_extent_buffer_fsid(struct extent_buffer *eb, const void *src);
247void write_extent_buffer_chunk_tree_uuid(struct extent_buffer *eb,
248 const void *src);
249void write_extent_buffer(struct extent_buffer *eb, const void *src,
250 unsigned long start, unsigned long len);
251void copy_extent_buffer_full(struct extent_buffer *dst,
252 struct extent_buffer *src);
253void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
254 unsigned long dst_offset, unsigned long src_offset,
255 unsigned long len);
256void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
257 unsigned long src_offset, unsigned long len);
258void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
259 unsigned long src_offset, unsigned long len);
260void memzero_extent_buffer(struct extent_buffer *eb, unsigned long start,
261 unsigned long len);
262int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start,
263 unsigned long pos);
264void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start,
265 unsigned long pos, unsigned long len);
266void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start,
267 unsigned long pos, unsigned long len);
268void clear_extent_buffer_dirty(struct extent_buffer *eb);
269bool set_extent_buffer_dirty(struct extent_buffer *eb);
270void set_extent_buffer_uptodate(struct extent_buffer *eb);
271void clear_extent_buffer_uptodate(struct extent_buffer *eb);
272int extent_buffer_under_io(struct extent_buffer *eb);
273int map_private_extent_buffer(const struct extent_buffer *eb,
274 unsigned long offset, unsigned long min_len,
275 char **map, unsigned long *map_start,
276 unsigned long *map_len);
277void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
278void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
279void extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end,
280 struct page *locked_page,
281 unsigned bits_to_clear,
282 unsigned long page_ops);
283struct bio *btrfs_bio_alloc(u64 first_byte);
284struct bio *btrfs_io_bio_alloc(unsigned int nr_iovecs);
285struct bio *btrfs_bio_clone(struct bio *bio);
286struct bio *btrfs_bio_clone_partial(struct bio *orig, int offset, int size);
287
288struct btrfs_fs_info;
289struct btrfs_inode;
290
291int repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start,
292 u64 length, u64 logical, struct page *page,
293 unsigned int pg_offset, int mirror_num);
294void end_extent_writepage(struct page *page, int err, u64 start, u64 end);
295int btrfs_repair_eb_io_failure(struct extent_buffer *eb, int mirror_num);
296
297/*
298 * When IO fails, either with EIO or csum verification fails, we
299 * try other mirrors that might have a good copy of the data. This
300 * io_failure_record is used to record state as we go through all the
301 * mirrors. If another mirror has good data, the page is set up to date
302 * and things continue. If a good mirror can't be found, the original
303 * bio end_io callback is called to indicate things have failed.
304 */
305struct io_failure_record {
306 struct page *page;
307 u64 start;
308 u64 len;
309 u64 logical;
310 unsigned long bio_flags;
311 int this_mirror;
312 int failed_mirror;
313 int in_validation;
314};
315
316
317bool btrfs_check_repairable(struct inode *inode, unsigned failed_bio_pages,
318 struct io_failure_record *failrec, int fail_mirror);
319struct bio *btrfs_create_repair_bio(struct inode *inode, struct bio *failed_bio,
320 struct io_failure_record *failrec,
321 struct page *page, int pg_offset, int icsum,
322 bio_end_io_t *endio_func, void *data);
323#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
324bool find_lock_delalloc_range(struct inode *inode,
325 struct page *locked_page, u64 *start,
326 u64 *end);
327#endif
328struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
329 u64 start);
330#endif