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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 <linux/fiemap.h>
9#include "ulist.h"
10
11/*
12 * flags for bio submission. The high bits indicate the compression
13 * type for this bio
14 */
15#define EXTENT_BIO_COMPRESSED 1
16#define EXTENT_BIO_FLAG_SHIFT 16
17
18enum {
19 EXTENT_BUFFER_UPTODATE,
20 EXTENT_BUFFER_DIRTY,
21 EXTENT_BUFFER_CORRUPT,
22 /* this got triggered by readahead */
23 EXTENT_BUFFER_READAHEAD,
24 EXTENT_BUFFER_TREE_REF,
25 EXTENT_BUFFER_STALE,
26 EXTENT_BUFFER_WRITEBACK,
27 /* read IO error */
28 EXTENT_BUFFER_READ_ERR,
29 EXTENT_BUFFER_UNMAPPED,
30 EXTENT_BUFFER_IN_TREE,
31 /* write IO error */
32 EXTENT_BUFFER_WRITE_ERR,
33};
34
35/* these are flags for __process_pages_contig */
36#define PAGE_UNLOCK (1 << 0)
37#define PAGE_CLEAR_DIRTY (1 << 1)
38#define PAGE_SET_WRITEBACK (1 << 2)
39#define PAGE_END_WRITEBACK (1 << 3)
40#define PAGE_SET_PRIVATE2 (1 << 4)
41#define PAGE_SET_ERROR (1 << 5)
42#define PAGE_LOCK (1 << 6)
43
44/*
45 * page->private values. Every page that is controlled by the extent
46 * map has page->private set to one.
47 */
48#define EXTENT_PAGE_PRIVATE 1
49
50/*
51 * The extent buffer bitmap operations are done with byte granularity instead of
52 * word granularity for two reasons:
53 * 1. The bitmaps must be little-endian on disk.
54 * 2. Bitmap items are not guaranteed to be aligned to a word and therefore a
55 * single word in a bitmap may straddle two pages in the extent buffer.
56 */
57#define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE)
58#define BYTE_MASK ((1 << BITS_PER_BYTE) - 1)
59#define BITMAP_FIRST_BYTE_MASK(start) \
60 ((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK)
61#define BITMAP_LAST_BYTE_MASK(nbits) \
62 (BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1)))
63
64struct btrfs_root;
65struct btrfs_inode;
66struct btrfs_io_bio;
67struct io_failure_record;
68struct extent_io_tree;
69
70typedef blk_status_t (submit_bio_hook_t)(struct inode *inode, struct bio *bio,
71 int mirror_num,
72 unsigned long bio_flags);
73
74typedef blk_status_t (extent_submit_bio_start_t)(void *private_data,
75 struct bio *bio, u64 bio_offset);
76
77struct extent_io_ops {
78 /*
79 * The following callbacks must be always defined, the function
80 * pointer will be called unconditionally.
81 */
82 submit_bio_hook_t *submit_bio_hook;
83 int (*readpage_end_io_hook)(struct btrfs_io_bio *io_bio, u64 phy_offset,
84 struct page *page, u64 start, u64 end,
85 int mirror);
86};
87
88
89#define INLINE_EXTENT_BUFFER_PAGES 16
90#define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_SIZE)
91struct extent_buffer {
92 u64 start;
93 unsigned long len;
94 unsigned long bflags;
95 struct btrfs_fs_info *fs_info;
96 spinlock_t refs_lock;
97 atomic_t refs;
98 atomic_t io_pages;
99 int read_mirror;
100 struct rcu_head rcu_head;
101 pid_t lock_owner;
102
103 int blocking_writers;
104 atomic_t blocking_readers;
105 bool lock_nested;
106 /* >= 0 if eb belongs to a log tree, -1 otherwise */
107 short log_index;
108
109 /* protects write locks */
110 rwlock_t lock;
111
112 /* readers use lock_wq while they wait for the write
113 * lock holders to unlock
114 */
115 wait_queue_head_t write_lock_wq;
116
117 /* writers use read_lock_wq while they wait for readers
118 * to unlock
119 */
120 wait_queue_head_t read_lock_wq;
121 struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
122#ifdef CONFIG_BTRFS_DEBUG
123 int spinning_writers;
124 atomic_t spinning_readers;
125 atomic_t read_locks;
126 int write_locks;
127 struct list_head leak_list;
128#endif
129};
130
131/*
132 * Structure to record how many bytes and which ranges are set/cleared
133 */
134struct extent_changeset {
135 /* How many bytes are set/cleared in this operation */
136 unsigned int bytes_changed;
137
138 /* Changed ranges */
139 struct ulist range_changed;
140};
141
142static inline void extent_changeset_init(struct extent_changeset *changeset)
143{
144 changeset->bytes_changed = 0;
145 ulist_init(&changeset->range_changed);
146}
147
148static inline struct extent_changeset *extent_changeset_alloc(void)
149{
150 struct extent_changeset *ret;
151
152 ret = kmalloc(sizeof(*ret), GFP_KERNEL);
153 if (!ret)
154 return NULL;
155
156 extent_changeset_init(ret);
157 return ret;
158}
159
160static inline void extent_changeset_release(struct extent_changeset *changeset)
161{
162 if (!changeset)
163 return;
164 changeset->bytes_changed = 0;
165 ulist_release(&changeset->range_changed);
166}
167
168static inline void extent_changeset_free(struct extent_changeset *changeset)
169{
170 if (!changeset)
171 return;
172 extent_changeset_release(changeset);
173 kfree(changeset);
174}
175
176static inline void extent_set_compress_type(unsigned long *bio_flags,
177 int compress_type)
178{
179 *bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT;
180}
181
182static inline int extent_compress_type(unsigned long bio_flags)
183{
184 return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
185}
186
187struct extent_map_tree;
188
189typedef struct extent_map *(get_extent_t)(struct btrfs_inode *inode,
190 struct page *page, size_t pg_offset,
191 u64 start, u64 len);
192
193int try_release_extent_mapping(struct page *page, gfp_t mask);
194int try_release_extent_buffer(struct page *page);
195
196int extent_read_full_page(struct page *page, get_extent_t *get_extent,
197 int mirror_num);
198int extent_write_full_page(struct page *page, struct writeback_control *wbc);
199int extent_write_locked_range(struct inode *inode, u64 start, u64 end,
200 int mode);
201int extent_writepages(struct address_space *mapping,
202 struct writeback_control *wbc);
203int btree_write_cache_pages(struct address_space *mapping,
204 struct writeback_control *wbc);
205void extent_readahead(struct readahead_control *rac);
206int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
207 u64 start, u64 len);
208void set_page_extent_mapped(struct page *page);
209
210struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
211 u64 start);
212struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
213 u64 start, unsigned long len);
214struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
215 u64 start);
216struct extent_buffer *btrfs_clone_extent_buffer(const struct extent_buffer *src);
217struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
218 u64 start);
219void free_extent_buffer(struct extent_buffer *eb);
220void free_extent_buffer_stale(struct extent_buffer *eb);
221#define WAIT_NONE 0
222#define WAIT_COMPLETE 1
223#define WAIT_PAGE_LOCK 2
224int read_extent_buffer_pages(struct extent_buffer *eb, int wait,
225 int mirror_num);
226void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
227
228static inline int num_extent_pages(const struct extent_buffer *eb)
229{
230 return (round_up(eb->start + eb->len, PAGE_SIZE) >> PAGE_SHIFT) -
231 (eb->start >> PAGE_SHIFT);
232}
233
234static inline int extent_buffer_uptodate(const struct extent_buffer *eb)
235{
236 return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
237}
238
239int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv,
240 unsigned long start, unsigned long len);
241void read_extent_buffer(const struct extent_buffer *eb, void *dst,
242 unsigned long start,
243 unsigned long len);
244int read_extent_buffer_to_user_nofault(const struct extent_buffer *eb,
245 void __user *dst, unsigned long start,
246 unsigned long len);
247void write_extent_buffer_fsid(const struct extent_buffer *eb, const void *src);
248void write_extent_buffer_chunk_tree_uuid(const struct extent_buffer *eb,
249 const void *src);
250void write_extent_buffer(const struct extent_buffer *eb, const void *src,
251 unsigned long start, unsigned long len);
252void copy_extent_buffer_full(const struct extent_buffer *dst,
253 const struct extent_buffer *src);
254void copy_extent_buffer(const struct extent_buffer *dst,
255 const struct extent_buffer *src,
256 unsigned long dst_offset, unsigned long src_offset,
257 unsigned long len);
258void memcpy_extent_buffer(const struct extent_buffer *dst,
259 unsigned long dst_offset, unsigned long src_offset,
260 unsigned long len);
261void memmove_extent_buffer(const struct extent_buffer *dst,
262 unsigned long dst_offset, unsigned long src_offset,
263 unsigned long len);
264void memzero_extent_buffer(const struct extent_buffer *eb, unsigned long start,
265 unsigned long len);
266int extent_buffer_test_bit(const struct extent_buffer *eb, unsigned long start,
267 unsigned long pos);
268void extent_buffer_bitmap_set(const struct extent_buffer *eb, unsigned long start,
269 unsigned long pos, unsigned long len);
270void extent_buffer_bitmap_clear(const struct extent_buffer *eb,
271 unsigned long start, unsigned long pos,
272 unsigned long len);
273void clear_extent_buffer_dirty(const struct extent_buffer *eb);
274bool set_extent_buffer_dirty(struct extent_buffer *eb);
275void set_extent_buffer_uptodate(struct extent_buffer *eb);
276void clear_extent_buffer_uptodate(struct extent_buffer *eb);
277int extent_buffer_under_io(const struct extent_buffer *eb);
278void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
279void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
280void extent_clear_unlock_delalloc(struct btrfs_inode *inode, u64 start, u64 end,
281 struct page *locked_page,
282 unsigned bits_to_clear,
283 unsigned long page_ops);
284struct bio *btrfs_bio_alloc(u64 first_byte);
285struct bio *btrfs_io_bio_alloc(unsigned int nr_iovecs);
286struct bio *btrfs_bio_clone(struct bio *bio);
287struct bio *btrfs_bio_clone_partial(struct bio *orig, int offset, int size);
288
289struct btrfs_fs_info;
290struct btrfs_inode;
291
292int repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start,
293 u64 length, u64 logical, struct page *page,
294 unsigned int pg_offset, int mirror_num);
295void end_extent_writepage(struct page *page, int err, u64 start, u64 end);
296int btrfs_repair_eb_io_failure(const struct extent_buffer *eb, int mirror_num);
297
298/*
299 * When IO fails, either with EIO or csum verification fails, we
300 * try other mirrors that might have a good copy of the data. This
301 * io_failure_record is used to record state as we go through all the
302 * mirrors. If another mirror has good data, the page is set up to date
303 * and things continue. If a good mirror can't be found, the original
304 * bio end_io callback is called to indicate things have failed.
305 */
306struct io_failure_record {
307 struct page *page;
308 u64 start;
309 u64 len;
310 u64 logical;
311 unsigned long bio_flags;
312 int this_mirror;
313 int failed_mirror;
314 int in_validation;
315};
316
317
318blk_status_t btrfs_submit_read_repair(struct inode *inode,
319 struct bio *failed_bio, u64 phy_offset,
320 struct page *page, unsigned int pgoff,
321 u64 start, u64 end, int failed_mirror,
322 submit_bio_hook_t *submit_bio_hook);
323
324#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
325bool find_lock_delalloc_range(struct inode *inode,
326 struct page *locked_page, u64 *start,
327 u64 *end);
328#endif
329struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
330 u64 start);
331
332#ifdef CONFIG_BTRFS_DEBUG
333void btrfs_extent_buffer_leak_debug_check(struct btrfs_fs_info *fs_info);
334#else
335#define btrfs_extent_buffer_leak_debug_check(fs_info) do {} while (0)
336#endif
337
338#endif
1#ifndef __EXTENTIO__
2#define __EXTENTIO__
3
4#include <linux/rbtree.h>
5
6/* bits for the extent state */
7#define EXTENT_DIRTY 1
8#define EXTENT_WRITEBACK (1 << 1)
9#define EXTENT_UPTODATE (1 << 2)
10#define EXTENT_LOCKED (1 << 3)
11#define EXTENT_NEW (1 << 4)
12#define EXTENT_DELALLOC (1 << 5)
13#define EXTENT_DEFRAG (1 << 6)
14#define EXTENT_DEFRAG_DONE (1 << 7)
15#define EXTENT_BUFFER_FILLED (1 << 8)
16#define EXTENT_BOUNDARY (1 << 9)
17#define EXTENT_NODATASUM (1 << 10)
18#define EXTENT_DO_ACCOUNTING (1 << 11)
19#define EXTENT_FIRST_DELALLOC (1 << 12)
20#define EXTENT_NEED_WAIT (1 << 13)
21#define EXTENT_DAMAGED (1 << 14)
22#define EXTENT_NORESERVE (1 << 15)
23#define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
24#define EXTENT_CTLBITS (EXTENT_DO_ACCOUNTING | EXTENT_FIRST_DELALLOC)
25
26/*
27 * flags for bio submission. The high bits indicate the compression
28 * type for this bio
29 */
30#define EXTENT_BIO_COMPRESSED 1
31#define EXTENT_BIO_TREE_LOG 2
32#define EXTENT_BIO_PARENT_LOCKED 4
33#define EXTENT_BIO_FLAG_SHIFT 16
34
35/* these are bit numbers for test/set bit */
36#define EXTENT_BUFFER_UPTODATE 0
37#define EXTENT_BUFFER_BLOCKING 1
38#define EXTENT_BUFFER_DIRTY 2
39#define EXTENT_BUFFER_CORRUPT 3
40#define EXTENT_BUFFER_READAHEAD 4 /* this got triggered by readahead */
41#define EXTENT_BUFFER_TREE_REF 5
42#define EXTENT_BUFFER_STALE 6
43#define EXTENT_BUFFER_WRITEBACK 7
44#define EXTENT_BUFFER_IOERR 8
45#define EXTENT_BUFFER_DUMMY 9
46#define EXTENT_BUFFER_IN_TREE 10
47
48/* these are flags for extent_clear_unlock_delalloc */
49#define PAGE_UNLOCK (1 << 0)
50#define PAGE_CLEAR_DIRTY (1 << 1)
51#define PAGE_SET_WRITEBACK (1 << 2)
52#define PAGE_END_WRITEBACK (1 << 3)
53#define PAGE_SET_PRIVATE2 (1 << 4)
54
55/*
56 * page->private values. Every page that is controlled by the extent
57 * map has page->private set to one.
58 */
59#define EXTENT_PAGE_PRIVATE 1
60#define EXTENT_PAGE_PRIVATE_FIRST_PAGE 3
61
62struct extent_state;
63struct btrfs_root;
64struct btrfs_io_bio;
65
66typedef int (extent_submit_bio_hook_t)(struct inode *inode, int rw,
67 struct bio *bio, int mirror_num,
68 unsigned long bio_flags, u64 bio_offset);
69struct extent_io_ops {
70 int (*fill_delalloc)(struct inode *inode, struct page *locked_page,
71 u64 start, u64 end, int *page_started,
72 unsigned long *nr_written);
73 int (*writepage_start_hook)(struct page *page, u64 start, u64 end);
74 int (*writepage_io_hook)(struct page *page, u64 start, u64 end);
75 extent_submit_bio_hook_t *submit_bio_hook;
76 int (*merge_bio_hook)(int rw, struct page *page, unsigned long offset,
77 size_t size, struct bio *bio,
78 unsigned long bio_flags);
79 int (*readpage_io_failed_hook)(struct page *page, int failed_mirror);
80 int (*readpage_end_io_hook)(struct btrfs_io_bio *io_bio, u64 phy_offset,
81 struct page *page, u64 start, u64 end,
82 int mirror);
83 int (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
84 struct extent_state *state, int uptodate);
85 void (*set_bit_hook)(struct inode *inode, struct extent_state *state,
86 unsigned long *bits);
87 void (*clear_bit_hook)(struct inode *inode, struct extent_state *state,
88 unsigned long *bits);
89 void (*merge_extent_hook)(struct inode *inode,
90 struct extent_state *new,
91 struct extent_state *other);
92 void (*split_extent_hook)(struct inode *inode,
93 struct extent_state *orig, u64 split);
94};
95
96struct extent_io_tree {
97 struct rb_root state;
98 struct address_space *mapping;
99 u64 dirty_bytes;
100 int track_uptodate;
101 spinlock_t lock;
102 struct extent_io_ops *ops;
103};
104
105struct extent_state {
106 u64 start;
107 u64 end; /* inclusive */
108 struct rb_node rb_node;
109
110 /* ADD NEW ELEMENTS AFTER THIS */
111 struct extent_io_tree *tree;
112 wait_queue_head_t wq;
113 atomic_t refs;
114 unsigned long state;
115
116 /* for use by the FS */
117 u64 private;
118
119#ifdef CONFIG_BTRFS_DEBUG
120 struct list_head leak_list;
121#endif
122};
123
124#define INLINE_EXTENT_BUFFER_PAGES 16
125#define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_CACHE_SIZE)
126struct extent_buffer {
127 u64 start;
128 unsigned long len;
129 unsigned long map_start;
130 unsigned long map_len;
131 unsigned long bflags;
132 struct btrfs_fs_info *fs_info;
133 spinlock_t refs_lock;
134 atomic_t refs;
135 atomic_t io_pages;
136 int read_mirror;
137 struct rcu_head rcu_head;
138 pid_t lock_owner;
139
140 /* count of read lock holders on the extent buffer */
141 atomic_t write_locks;
142 atomic_t read_locks;
143 atomic_t blocking_writers;
144 atomic_t blocking_readers;
145 atomic_t spinning_readers;
146 atomic_t spinning_writers;
147 int lock_nested;
148
149 /* protects write locks */
150 rwlock_t lock;
151
152 /* readers use lock_wq while they wait for the write
153 * lock holders to unlock
154 */
155 wait_queue_head_t write_lock_wq;
156
157 /* writers use read_lock_wq while they wait for readers
158 * to unlock
159 */
160 wait_queue_head_t read_lock_wq;
161 wait_queue_head_t lock_wq;
162 struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
163#ifdef CONFIG_BTRFS_DEBUG
164 struct list_head leak_list;
165#endif
166};
167
168static inline void extent_set_compress_type(unsigned long *bio_flags,
169 int compress_type)
170{
171 *bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT;
172}
173
174static inline int extent_compress_type(unsigned long bio_flags)
175{
176 return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
177}
178
179struct extent_map_tree;
180
181typedef struct extent_map *(get_extent_t)(struct inode *inode,
182 struct page *page,
183 size_t pg_offset,
184 u64 start, u64 len,
185 int create);
186
187void extent_io_tree_init(struct extent_io_tree *tree,
188 struct address_space *mapping);
189int try_release_extent_mapping(struct extent_map_tree *map,
190 struct extent_io_tree *tree, struct page *page,
191 gfp_t mask);
192int try_release_extent_buffer(struct page *page);
193int lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
194int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
195 unsigned long bits, struct extent_state **cached);
196int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end);
197int unlock_extent_cached(struct extent_io_tree *tree, u64 start, u64 end,
198 struct extent_state **cached, gfp_t mask);
199int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
200int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
201 get_extent_t *get_extent, int mirror_num);
202int extent_read_full_page_nolock(struct extent_io_tree *tree, struct page *page,
203 get_extent_t *get_extent, int mirror_num);
204int __init extent_io_init(void);
205void extent_io_exit(void);
206
207u64 count_range_bits(struct extent_io_tree *tree,
208 u64 *start, u64 search_end,
209 u64 max_bytes, unsigned long bits, int contig);
210
211void free_extent_state(struct extent_state *state);
212int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
213 unsigned long bits, int filled,
214 struct extent_state *cached_state);
215int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
216 unsigned long bits, gfp_t mask);
217int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
218 unsigned long bits, int wake, int delete,
219 struct extent_state **cached, gfp_t mask);
220int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
221 unsigned long bits, gfp_t mask);
222int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
223 unsigned long bits, u64 *failed_start,
224 struct extent_state **cached_state, gfp_t mask);
225int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
226 struct extent_state **cached_state, gfp_t mask);
227int clear_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
228 struct extent_state **cached_state, gfp_t mask);
229int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end,
230 gfp_t mask);
231int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
232 gfp_t mask);
233int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
234 gfp_t mask);
235int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
236 unsigned long bits, unsigned long clear_bits,
237 struct extent_state **cached_state, gfp_t mask);
238int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end,
239 struct extent_state **cached_state, gfp_t mask);
240int set_extent_defrag(struct extent_io_tree *tree, u64 start, u64 end,
241 struct extent_state **cached_state, gfp_t mask);
242int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
243 u64 *start_ret, u64 *end_ret, unsigned long bits,
244 struct extent_state **cached_state);
245int extent_invalidatepage(struct extent_io_tree *tree,
246 struct page *page, unsigned long offset);
247int extent_write_full_page(struct extent_io_tree *tree, struct page *page,
248 get_extent_t *get_extent,
249 struct writeback_control *wbc);
250int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode,
251 u64 start, u64 end, get_extent_t *get_extent,
252 int mode);
253int extent_writepages(struct extent_io_tree *tree,
254 struct address_space *mapping,
255 get_extent_t *get_extent,
256 struct writeback_control *wbc);
257int btree_write_cache_pages(struct address_space *mapping,
258 struct writeback_control *wbc);
259int extent_readpages(struct extent_io_tree *tree,
260 struct address_space *mapping,
261 struct list_head *pages, unsigned nr_pages,
262 get_extent_t get_extent);
263int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
264 __u64 start, __u64 len, get_extent_t *get_extent);
265int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private);
266void set_page_extent_mapped(struct page *page);
267
268struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
269 u64 start, unsigned long len);
270struct extent_buffer *alloc_dummy_extent_buffer(u64 start, unsigned long len);
271struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
272struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
273 u64 start);
274void free_extent_buffer(struct extent_buffer *eb);
275void free_extent_buffer_stale(struct extent_buffer *eb);
276#define WAIT_NONE 0
277#define WAIT_COMPLETE 1
278#define WAIT_PAGE_LOCK 2
279int read_extent_buffer_pages(struct extent_io_tree *tree,
280 struct extent_buffer *eb, u64 start, int wait,
281 get_extent_t *get_extent, int mirror_num);
282void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
283
284static inline unsigned long num_extent_pages(u64 start, u64 len)
285{
286 return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) -
287 (start >> PAGE_CACHE_SHIFT);
288}
289
290static inline struct page *extent_buffer_page(struct extent_buffer *eb,
291 unsigned long i)
292{
293 return eb->pages[i];
294}
295
296static inline void extent_buffer_get(struct extent_buffer *eb)
297{
298 atomic_inc(&eb->refs);
299}
300
301int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
302 unsigned long start,
303 unsigned long len);
304void read_extent_buffer(struct extent_buffer *eb, void *dst,
305 unsigned long start,
306 unsigned long len);
307void write_extent_buffer(struct extent_buffer *eb, const void *src,
308 unsigned long start, unsigned long len);
309void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
310 unsigned long dst_offset, unsigned long src_offset,
311 unsigned long len);
312void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
313 unsigned long src_offset, unsigned long len);
314void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
315 unsigned long src_offset, unsigned long len);
316void memset_extent_buffer(struct extent_buffer *eb, char c,
317 unsigned long start, unsigned long len);
318void clear_extent_buffer_dirty(struct extent_buffer *eb);
319int set_extent_buffer_dirty(struct extent_buffer *eb);
320int set_extent_buffer_uptodate(struct extent_buffer *eb);
321int clear_extent_buffer_uptodate(struct extent_buffer *eb);
322int extent_buffer_uptodate(struct extent_buffer *eb);
323int extent_buffer_under_io(struct extent_buffer *eb);
324int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
325 unsigned long min_len, char **map,
326 unsigned long *map_start,
327 unsigned long *map_len);
328int extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
329int extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
330int extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end,
331 struct page *locked_page,
332 unsigned long bits_to_clear,
333 unsigned long page_ops);
334struct bio *
335btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
336 gfp_t gfp_flags);
337struct bio *btrfs_io_bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs);
338struct bio *btrfs_bio_clone(struct bio *bio, gfp_t gfp_mask);
339
340struct btrfs_fs_info;
341
342int repair_io_failure(struct btrfs_fs_info *fs_info, u64 start,
343 u64 length, u64 logical, struct page *page,
344 int mirror_num);
345int end_extent_writepage(struct page *page, int err, u64 start, u64 end);
346int repair_eb_io_failure(struct btrfs_root *root, struct extent_buffer *eb,
347 int mirror_num);
348#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
349noinline u64 find_lock_delalloc_range(struct inode *inode,
350 struct extent_io_tree *tree,
351 struct page *locked_page, u64 *start,
352 u64 *end, u64 max_bytes);
353#endif
354#endif