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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 <linux/btrfs_tree.h>
10#include "compression.h"
11#include "ulist.h"
12#include "misc.h"
13
14enum {
15 EXTENT_BUFFER_UPTODATE,
16 EXTENT_BUFFER_DIRTY,
17 EXTENT_BUFFER_CORRUPT,
18 /* this got triggered by readahead */
19 EXTENT_BUFFER_READAHEAD,
20 EXTENT_BUFFER_TREE_REF,
21 EXTENT_BUFFER_STALE,
22 EXTENT_BUFFER_WRITEBACK,
23 /* read IO error */
24 EXTENT_BUFFER_READ_ERR,
25 EXTENT_BUFFER_UNMAPPED,
26 EXTENT_BUFFER_IN_TREE,
27 /* write IO error */
28 EXTENT_BUFFER_WRITE_ERR,
29 EXTENT_BUFFER_NO_CHECK,
30};
31
32/* these are flags for __process_pages_contig */
33enum {
34 ENUM_BIT(PAGE_UNLOCK),
35 /* Page starts writeback, clear dirty bit and set writeback bit */
36 ENUM_BIT(PAGE_START_WRITEBACK),
37 ENUM_BIT(PAGE_END_WRITEBACK),
38 ENUM_BIT(PAGE_SET_ORDERED),
39 ENUM_BIT(PAGE_SET_ERROR),
40 ENUM_BIT(PAGE_LOCK),
41};
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_bio;
64struct btrfs_root;
65struct btrfs_inode;
66struct btrfs_fs_info;
67struct io_failure_record;
68struct extent_io_tree;
69struct btrfs_tree_parent_check;
70
71int __init extent_buffer_init_cachep(void);
72void __cold extent_buffer_free_cachep(void);
73
74#define INLINE_EXTENT_BUFFER_PAGES (BTRFS_MAX_METADATA_BLOCKSIZE / PAGE_SIZE)
75struct extent_buffer {
76 u64 start;
77 unsigned long len;
78 unsigned long bflags;
79 struct btrfs_fs_info *fs_info;
80 spinlock_t refs_lock;
81 atomic_t refs;
82 atomic_t io_pages;
83 int read_mirror;
84 struct rcu_head rcu_head;
85 pid_t lock_owner;
86 /* >= 0 if eb belongs to a log tree, -1 otherwise */
87 s8 log_index;
88
89 struct rw_semaphore lock;
90
91 struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
92 struct list_head release_list;
93#ifdef CONFIG_BTRFS_DEBUG
94 struct list_head leak_list;
95#endif
96};
97
98/*
99 * Get the correct offset inside the page of extent buffer.
100 *
101 * @eb: target extent buffer
102 * @start: offset inside the extent buffer
103 *
104 * Will handle both sectorsize == PAGE_SIZE and sectorsize < PAGE_SIZE cases.
105 */
106static inline size_t get_eb_offset_in_page(const struct extent_buffer *eb,
107 unsigned long offset)
108{
109 /*
110 * For sectorsize == PAGE_SIZE case, eb->start will always be aligned
111 * to PAGE_SIZE, thus adding it won't cause any difference.
112 *
113 * For sectorsize < PAGE_SIZE, we must only read the data that belongs
114 * to the eb, thus we have to take the eb->start into consideration.
115 */
116 return offset_in_page(offset + eb->start);
117}
118
119static inline unsigned long get_eb_page_index(unsigned long offset)
120{
121 /*
122 * For sectorsize == PAGE_SIZE case, plain >> PAGE_SHIFT is enough.
123 *
124 * For sectorsize < PAGE_SIZE case, we only support 64K PAGE_SIZE,
125 * and have ensured that all tree blocks are contained in one page,
126 * thus we always get index == 0.
127 */
128 return offset >> PAGE_SHIFT;
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 u64 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
176struct extent_map_tree;
177
178int try_release_extent_mapping(struct page *page, gfp_t mask);
179int try_release_extent_buffer(struct page *page);
180
181int btrfs_read_folio(struct file *file, struct folio *folio);
182int extent_write_locked_range(struct inode *inode, u64 start, u64 end);
183int extent_writepages(struct address_space *mapping,
184 struct writeback_control *wbc);
185int btree_write_cache_pages(struct address_space *mapping,
186 struct writeback_control *wbc);
187void extent_readahead(struct readahead_control *rac);
188int extent_fiemap(struct btrfs_inode *inode, struct fiemap_extent_info *fieinfo,
189 u64 start, u64 len);
190int set_page_extent_mapped(struct page *page);
191void clear_page_extent_mapped(struct page *page);
192
193struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
194 u64 start, u64 owner_root, int level);
195struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
196 u64 start, unsigned long len);
197struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
198 u64 start);
199struct extent_buffer *btrfs_clone_extent_buffer(const struct extent_buffer *src);
200struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
201 u64 start);
202void free_extent_buffer(struct extent_buffer *eb);
203void free_extent_buffer_stale(struct extent_buffer *eb);
204#define WAIT_NONE 0
205#define WAIT_COMPLETE 1
206#define WAIT_PAGE_LOCK 2
207int read_extent_buffer_pages(struct extent_buffer *eb, int wait, int mirror_num,
208 struct btrfs_tree_parent_check *parent_check);
209void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
210void btrfs_readahead_tree_block(struct btrfs_fs_info *fs_info,
211 u64 bytenr, u64 owner_root, u64 gen, int level);
212void btrfs_readahead_node_child(struct extent_buffer *node, int slot);
213
214static inline int num_extent_pages(const struct extent_buffer *eb)
215{
216 /*
217 * For sectorsize == PAGE_SIZE case, since nodesize is always aligned to
218 * sectorsize, it's just eb->len >> PAGE_SHIFT.
219 *
220 * For sectorsize < PAGE_SIZE case, we could have nodesize < PAGE_SIZE,
221 * thus have to ensure we get at least one page.
222 */
223 return (eb->len >> PAGE_SHIFT) ?: 1;
224}
225
226static inline int extent_buffer_uptodate(const struct extent_buffer *eb)
227{
228 return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
229}
230
231int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv,
232 unsigned long start, unsigned long len);
233void read_extent_buffer(const struct extent_buffer *eb, void *dst,
234 unsigned long start,
235 unsigned long len);
236int read_extent_buffer_to_user_nofault(const struct extent_buffer *eb,
237 void __user *dst, unsigned long start,
238 unsigned long len);
239void write_extent_buffer_fsid(const struct extent_buffer *eb, const void *src);
240void write_extent_buffer_chunk_tree_uuid(const struct extent_buffer *eb,
241 const void *src);
242void write_extent_buffer(const struct extent_buffer *eb, const void *src,
243 unsigned long start, unsigned long len);
244void copy_extent_buffer_full(const struct extent_buffer *dst,
245 const struct extent_buffer *src);
246void copy_extent_buffer(const struct extent_buffer *dst,
247 const struct extent_buffer *src,
248 unsigned long dst_offset, unsigned long src_offset,
249 unsigned long len);
250void memcpy_extent_buffer(const struct extent_buffer *dst,
251 unsigned long dst_offset, unsigned long src_offset,
252 unsigned long len);
253void memmove_extent_buffer(const struct extent_buffer *dst,
254 unsigned long dst_offset, unsigned long src_offset,
255 unsigned long len);
256void memzero_extent_buffer(const struct extent_buffer *eb, unsigned long start,
257 unsigned long len);
258int extent_buffer_test_bit(const struct extent_buffer *eb, unsigned long start,
259 unsigned long pos);
260void extent_buffer_bitmap_set(const struct extent_buffer *eb, unsigned long start,
261 unsigned long pos, unsigned long len);
262void extent_buffer_bitmap_clear(const struct extent_buffer *eb,
263 unsigned long start, unsigned long pos,
264 unsigned long len);
265void clear_extent_buffer_dirty(const struct extent_buffer *eb);
266bool set_extent_buffer_dirty(struct extent_buffer *eb);
267void set_extent_buffer_uptodate(struct extent_buffer *eb);
268void clear_extent_buffer_uptodate(struct extent_buffer *eb);
269int extent_buffer_under_io(const struct extent_buffer *eb);
270void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
271void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
272void extent_clear_unlock_delalloc(struct btrfs_inode *inode, u64 start, u64 end,
273 struct page *locked_page,
274 u32 bits_to_clear, unsigned long page_ops);
275int extent_invalidate_folio(struct extent_io_tree *tree,
276 struct folio *folio, size_t offset);
277
278int btrfs_alloc_page_array(unsigned int nr_pages, struct page **page_array);
279
280void end_extent_writepage(struct page *page, int err, u64 start, u64 end);
281
282/*
283 * When IO fails, either with EIO or csum verification fails, we
284 * try other mirrors that might have a good copy of the data. This
285 * io_failure_record is used to record state as we go through all the
286 * mirrors. If another mirror has good data, the sector is set up to date
287 * and things continue. If a good mirror can't be found, the original
288 * bio end_io callback is called to indicate things have failed.
289 */
290struct io_failure_record {
291 /* Use rb_simple_node for search/insert */
292 struct {
293 struct rb_node rb_node;
294 u64 bytenr;
295 };
296 struct page *page;
297 u64 len;
298 u64 logical;
299 int this_mirror;
300 int failed_mirror;
301 int num_copies;
302};
303
304int btrfs_repair_one_sector(struct btrfs_inode *inode, struct btrfs_bio *failed_bbio,
305 u32 bio_offset, struct page *page, unsigned int pgoff,
306 bool submit_buffered);
307void btrfs_free_io_failure_record(struct btrfs_inode *inode, u64 start, u64 end);
308int btrfs_clean_io_failure(struct btrfs_inode *inode, u64 start,
309 struct page *page, unsigned int pg_offset);
310
311#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
312bool find_lock_delalloc_range(struct inode *inode,
313 struct page *locked_page, u64 *start,
314 u64 *end);
315#endif
316struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
317 u64 start);
318
319#ifdef CONFIG_BTRFS_DEBUG
320void btrfs_extent_buffer_leak_debug_check(struct btrfs_fs_info *fs_info);
321#else
322#define btrfs_extent_buffer_leak_debug_check(fs_info) do {} while (0)
323#endif
324
325#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