extent_io.h 19 KB

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  1. /* SPDX-License-Identifier: GPL-2.0 */
  2. #ifndef __EXTENTIO__
  3. #define __EXTENTIO__
  4. #include <linux/rbtree.h>
  5. #include <linux/refcount.h>
  6. #include "ulist.h"
  7. /* bits for the extent state */
  8. #define EXTENT_DIRTY (1U << 0)
  9. #define EXTENT_WRITEBACK (1U << 1)
  10. #define EXTENT_UPTODATE (1U << 2)
  11. #define EXTENT_LOCKED (1U << 3)
  12. #define EXTENT_NEW (1U << 4)
  13. #define EXTENT_DELALLOC (1U << 5)
  14. #define EXTENT_DEFRAG (1U << 6)
  15. #define EXTENT_BOUNDARY (1U << 9)
  16. #define EXTENT_NODATASUM (1U << 10)
  17. #define EXTENT_CLEAR_META_RESV (1U << 11)
  18. #define EXTENT_FIRST_DELALLOC (1U << 12)
  19. #define EXTENT_NEED_WAIT (1U << 13)
  20. #define EXTENT_DAMAGED (1U << 14)
  21. #define EXTENT_NORESERVE (1U << 15)
  22. #define EXTENT_QGROUP_RESERVED (1U << 16)
  23. #define EXTENT_CLEAR_DATA_RESV (1U << 17)
  24. #define EXTENT_DELALLOC_NEW (1U << 18)
  25. #define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
  26. #define EXTENT_DO_ACCOUNTING (EXTENT_CLEAR_META_RESV | \
  27. EXTENT_CLEAR_DATA_RESV)
  28. #define EXTENT_CTLBITS (EXTENT_DO_ACCOUNTING | EXTENT_FIRST_DELALLOC)
  29. /*
  30. * flags for bio submission. The high bits indicate the compression
  31. * type for this bio
  32. */
  33. #define EXTENT_BIO_COMPRESSED 1
  34. #define EXTENT_BIO_FLAG_SHIFT 16
  35. /* these are bit numbers for test/set bit */
  36. #define EXTENT_BUFFER_UPTODATE 0
  37. #define EXTENT_BUFFER_DIRTY 2
  38. #define EXTENT_BUFFER_CORRUPT 3
  39. #define EXTENT_BUFFER_READAHEAD 4 /* this got triggered by readahead */
  40. #define EXTENT_BUFFER_TREE_REF 5
  41. #define EXTENT_BUFFER_STALE 6
  42. #define EXTENT_BUFFER_WRITEBACK 7
  43. #define EXTENT_BUFFER_READ_ERR 8 /* read IO error */
  44. #define EXTENT_BUFFER_DUMMY 9
  45. #define EXTENT_BUFFER_IN_TREE 10
  46. #define EXTENT_BUFFER_WRITE_ERR 11 /* write IO error */
  47. /* these are flags for __process_pages_contig */
  48. #define PAGE_UNLOCK (1 << 0)
  49. #define PAGE_CLEAR_DIRTY (1 << 1)
  50. #define PAGE_SET_WRITEBACK (1 << 2)
  51. #define PAGE_END_WRITEBACK (1 << 3)
  52. #define PAGE_SET_PRIVATE2 (1 << 4)
  53. #define PAGE_SET_ERROR (1 << 5)
  54. #define PAGE_LOCK (1 << 6)
  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. /*
  61. * The extent buffer bitmap operations are done with byte granularity instead of
  62. * word granularity for two reasons:
  63. * 1. The bitmaps must be little-endian on disk.
  64. * 2. Bitmap items are not guaranteed to be aligned to a word and therefore a
  65. * single word in a bitmap may straddle two pages in the extent buffer.
  66. */
  67. #define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE)
  68. #define BYTE_MASK ((1 << BITS_PER_BYTE) - 1)
  69. #define BITMAP_FIRST_BYTE_MASK(start) \
  70. ((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK)
  71. #define BITMAP_LAST_BYTE_MASK(nbits) \
  72. (BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1)))
  73. static inline int le_test_bit(int nr, const u8 *addr)
  74. {
  75. return 1U & (addr[BIT_BYTE(nr)] >> (nr & (BITS_PER_BYTE-1)));
  76. }
  77. extern void le_bitmap_set(u8 *map, unsigned int start, int len);
  78. extern void le_bitmap_clear(u8 *map, unsigned int start, int len);
  79. struct extent_state;
  80. struct btrfs_root;
  81. struct btrfs_inode;
  82. struct btrfs_io_bio;
  83. struct io_failure_record;
  84. typedef blk_status_t (extent_submit_bio_hook_t)(void *private_data, struct bio *bio,
  85. int mirror_num, unsigned long bio_flags,
  86. u64 bio_offset);
  87. struct extent_io_ops {
  88. /*
  89. * The following callbacks must be allways defined, the function
  90. * pointer will be called unconditionally.
  91. */
  92. extent_submit_bio_hook_t *submit_bio_hook;
  93. int (*readpage_end_io_hook)(struct btrfs_io_bio *io_bio, u64 phy_offset,
  94. struct page *page, u64 start, u64 end,
  95. int mirror);
  96. int (*merge_bio_hook)(struct page *page, unsigned long offset,
  97. size_t size, struct bio *bio,
  98. unsigned long bio_flags);
  99. int (*readpage_io_failed_hook)(struct page *page, int failed_mirror);
  100. struct btrfs_fs_info *(*tree_fs_info)(void *private_data);
  101. void (*set_range_writeback)(void *private_data, u64 start, u64 end);
  102. /*
  103. * Optional hooks, called if the pointer is not NULL
  104. */
  105. int (*fill_delalloc)(void *private_data, struct page *locked_page,
  106. u64 start, u64 end, int *page_started,
  107. unsigned long *nr_written,
  108. struct writeback_control *wbc);
  109. int (*writepage_start_hook)(struct page *page, u64 start, u64 end);
  110. void (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
  111. struct extent_state *state, int uptodate);
  112. void (*set_bit_hook)(void *private_data, struct extent_state *state,
  113. unsigned *bits);
  114. void (*clear_bit_hook)(void *private_data,
  115. struct extent_state *state,
  116. unsigned *bits);
  117. void (*merge_extent_hook)(void *private_data,
  118. struct extent_state *new,
  119. struct extent_state *other);
  120. void (*split_extent_hook)(void *private_data,
  121. struct extent_state *orig, u64 split);
  122. void (*check_extent_io_range)(void *private_data, const char *caller,
  123. u64 start, u64 end);
  124. };
  125. struct extent_io_tree {
  126. struct rb_root state;
  127. void *private_data;
  128. u64 dirty_bytes;
  129. int track_uptodate;
  130. spinlock_t lock;
  131. const struct extent_io_ops *ops;
  132. };
  133. struct extent_state {
  134. u64 start;
  135. u64 end; /* inclusive */
  136. struct rb_node rb_node;
  137. /* ADD NEW ELEMENTS AFTER THIS */
  138. wait_queue_head_t wq;
  139. refcount_t refs;
  140. unsigned state;
  141. struct io_failure_record *failrec;
  142. #ifdef CONFIG_BTRFS_DEBUG
  143. struct list_head leak_list;
  144. #endif
  145. };
  146. #define INLINE_EXTENT_BUFFER_PAGES 16
  147. #define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_SIZE)
  148. struct extent_buffer {
  149. u64 start;
  150. unsigned long len;
  151. unsigned long bflags;
  152. struct btrfs_fs_info *fs_info;
  153. spinlock_t refs_lock;
  154. atomic_t refs;
  155. atomic_t io_pages;
  156. int read_mirror;
  157. struct rcu_head rcu_head;
  158. pid_t lock_owner;
  159. /* count of read lock holders on the extent buffer */
  160. atomic_t write_locks;
  161. atomic_t read_locks;
  162. atomic_t blocking_writers;
  163. atomic_t blocking_readers;
  164. atomic_t spinning_readers;
  165. atomic_t spinning_writers;
  166. short lock_nested;
  167. /* >= 0 if eb belongs to a log tree, -1 otherwise */
  168. short log_index;
  169. /* protects write locks */
  170. rwlock_t lock;
  171. /* readers use lock_wq while they wait for the write
  172. * lock holders to unlock
  173. */
  174. wait_queue_head_t write_lock_wq;
  175. /* writers use read_lock_wq while they wait for readers
  176. * to unlock
  177. */
  178. wait_queue_head_t read_lock_wq;
  179. struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
  180. #ifdef CONFIG_BTRFS_DEBUG
  181. struct list_head leak_list;
  182. #endif
  183. };
  184. /*
  185. * Structure to record how many bytes and which ranges are set/cleared
  186. */
  187. struct extent_changeset {
  188. /* How many bytes are set/cleared in this operation */
  189. unsigned int bytes_changed;
  190. /* Changed ranges */
  191. struct ulist range_changed;
  192. };
  193. static inline void extent_changeset_init(struct extent_changeset *changeset)
  194. {
  195. changeset->bytes_changed = 0;
  196. ulist_init(&changeset->range_changed);
  197. }
  198. static inline struct extent_changeset *extent_changeset_alloc(void)
  199. {
  200. struct extent_changeset *ret;
  201. ret = kmalloc(sizeof(*ret), GFP_KERNEL);
  202. if (!ret)
  203. return NULL;
  204. extent_changeset_init(ret);
  205. return ret;
  206. }
  207. static inline void extent_changeset_release(struct extent_changeset *changeset)
  208. {
  209. if (!changeset)
  210. return;
  211. changeset->bytes_changed = 0;
  212. ulist_release(&changeset->range_changed);
  213. }
  214. static inline void extent_changeset_free(struct extent_changeset *changeset)
  215. {
  216. if (!changeset)
  217. return;
  218. extent_changeset_release(changeset);
  219. kfree(changeset);
  220. }
  221. static inline void extent_set_compress_type(unsigned long *bio_flags,
  222. int compress_type)
  223. {
  224. *bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT;
  225. }
  226. static inline int extent_compress_type(unsigned long bio_flags)
  227. {
  228. return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
  229. }
  230. struct extent_map_tree;
  231. typedef struct extent_map *(get_extent_t)(struct btrfs_inode *inode,
  232. struct page *page,
  233. size_t pg_offset,
  234. u64 start, u64 len,
  235. int create);
  236. void extent_io_tree_init(struct extent_io_tree *tree, void *private_data);
  237. int try_release_extent_mapping(struct extent_map_tree *map,
  238. struct extent_io_tree *tree, struct page *page,
  239. gfp_t mask);
  240. int try_release_extent_buffer(struct page *page);
  241. int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
  242. struct extent_state **cached);
  243. static inline int lock_extent(struct extent_io_tree *tree, u64 start, u64 end)
  244. {
  245. return lock_extent_bits(tree, start, end, NULL);
  246. }
  247. int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
  248. int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
  249. get_extent_t *get_extent, int mirror_num);
  250. int __init extent_io_init(void);
  251. void extent_io_exit(void);
  252. u64 count_range_bits(struct extent_io_tree *tree,
  253. u64 *start, u64 search_end,
  254. u64 max_bytes, unsigned bits, int contig);
  255. void free_extent_state(struct extent_state *state);
  256. int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
  257. unsigned bits, int filled,
  258. struct extent_state *cached_state);
  259. int clear_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
  260. unsigned bits, struct extent_changeset *changeset);
  261. int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
  262. unsigned bits, int wake, int delete,
  263. struct extent_state **cached);
  264. int __clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
  265. unsigned bits, int wake, int delete,
  266. struct extent_state **cached, gfp_t mask,
  267. struct extent_changeset *changeset);
  268. static inline int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end)
  269. {
  270. return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL);
  271. }
  272. static inline int unlock_extent_cached(struct extent_io_tree *tree, u64 start,
  273. u64 end, struct extent_state **cached)
  274. {
  275. return __clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
  276. GFP_NOFS, NULL);
  277. }
  278. static inline int unlock_extent_cached_atomic(struct extent_io_tree *tree,
  279. u64 start, u64 end, struct extent_state **cached)
  280. {
  281. return __clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
  282. GFP_ATOMIC, NULL);
  283. }
  284. static inline int clear_extent_bits(struct extent_io_tree *tree, u64 start,
  285. u64 end, unsigned bits)
  286. {
  287. int wake = 0;
  288. if (bits & EXTENT_LOCKED)
  289. wake = 1;
  290. return clear_extent_bit(tree, start, end, bits, wake, 0, NULL);
  291. }
  292. int set_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
  293. unsigned bits, struct extent_changeset *changeset);
  294. int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
  295. unsigned bits, u64 *failed_start,
  296. struct extent_state **cached_state, gfp_t mask);
  297. static inline int set_extent_bits(struct extent_io_tree *tree, u64 start,
  298. u64 end, unsigned bits)
  299. {
  300. return set_extent_bit(tree, start, end, bits, NULL, NULL, GFP_NOFS);
  301. }
  302. static inline int clear_extent_uptodate(struct extent_io_tree *tree, u64 start,
  303. u64 end, struct extent_state **cached_state)
  304. {
  305. return __clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0,
  306. cached_state, GFP_NOFS, NULL);
  307. }
  308. static inline int set_extent_dirty(struct extent_io_tree *tree, u64 start,
  309. u64 end, gfp_t mask)
  310. {
  311. return set_extent_bit(tree, start, end, EXTENT_DIRTY, NULL,
  312. NULL, mask);
  313. }
  314. static inline int clear_extent_dirty(struct extent_io_tree *tree, u64 start,
  315. u64 end)
  316. {
  317. return clear_extent_bit(tree, start, end,
  318. EXTENT_DIRTY | EXTENT_DELALLOC |
  319. EXTENT_DO_ACCOUNTING, 0, 0, NULL);
  320. }
  321. int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
  322. unsigned bits, unsigned clear_bits,
  323. struct extent_state **cached_state);
  324. static inline int set_extent_delalloc(struct extent_io_tree *tree, u64 start,
  325. u64 end, unsigned int extra_bits,
  326. struct extent_state **cached_state)
  327. {
  328. return set_extent_bit(tree, start, end,
  329. EXTENT_DELALLOC | EXTENT_UPTODATE | extra_bits,
  330. NULL, cached_state, GFP_NOFS);
  331. }
  332. static inline int set_extent_defrag(struct extent_io_tree *tree, u64 start,
  333. u64 end, struct extent_state **cached_state)
  334. {
  335. return set_extent_bit(tree, start, end,
  336. EXTENT_DELALLOC | EXTENT_UPTODATE | EXTENT_DEFRAG,
  337. NULL, cached_state, GFP_NOFS);
  338. }
  339. static inline int set_extent_new(struct extent_io_tree *tree, u64 start,
  340. u64 end)
  341. {
  342. return set_extent_bit(tree, start, end, EXTENT_NEW, NULL, NULL,
  343. GFP_NOFS);
  344. }
  345. static inline int set_extent_uptodate(struct extent_io_tree *tree, u64 start,
  346. u64 end, struct extent_state **cached_state, gfp_t mask)
  347. {
  348. return set_extent_bit(tree, start, end, EXTENT_UPTODATE, NULL,
  349. cached_state, mask);
  350. }
  351. int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
  352. u64 *start_ret, u64 *end_ret, unsigned bits,
  353. struct extent_state **cached_state);
  354. int extent_invalidatepage(struct extent_io_tree *tree,
  355. struct page *page, unsigned long offset);
  356. int extent_write_full_page(struct page *page, struct writeback_control *wbc);
  357. int extent_write_locked_range(struct inode *inode, u64 start, u64 end,
  358. int mode);
  359. int extent_writepages(struct extent_io_tree *tree,
  360. struct address_space *mapping,
  361. struct writeback_control *wbc);
  362. int btree_write_cache_pages(struct address_space *mapping,
  363. struct writeback_control *wbc);
  364. int extent_readpages(struct extent_io_tree *tree,
  365. struct address_space *mapping,
  366. struct list_head *pages, unsigned nr_pages);
  367. int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
  368. __u64 start, __u64 len);
  369. void set_page_extent_mapped(struct page *page);
  370. struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
  371. u64 start);
  372. struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
  373. u64 start, unsigned long len);
  374. struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
  375. u64 start);
  376. struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
  377. struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
  378. u64 start);
  379. void free_extent_buffer(struct extent_buffer *eb);
  380. void free_extent_buffer_stale(struct extent_buffer *eb);
  381. #define WAIT_NONE 0
  382. #define WAIT_COMPLETE 1
  383. #define WAIT_PAGE_LOCK 2
  384. int read_extent_buffer_pages(struct extent_io_tree *tree,
  385. struct extent_buffer *eb, int wait,
  386. int mirror_num);
  387. void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
  388. static inline unsigned long num_extent_pages(u64 start, u64 len)
  389. {
  390. return ((start + len + PAGE_SIZE - 1) >> PAGE_SHIFT) -
  391. (start >> PAGE_SHIFT);
  392. }
  393. static inline void extent_buffer_get(struct extent_buffer *eb)
  394. {
  395. atomic_inc(&eb->refs);
  396. }
  397. int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv,
  398. unsigned long start, unsigned long len);
  399. void read_extent_buffer(const struct extent_buffer *eb, void *dst,
  400. unsigned long start,
  401. unsigned long len);
  402. int read_extent_buffer_to_user(const struct extent_buffer *eb,
  403. void __user *dst, unsigned long start,
  404. unsigned long len);
  405. void write_extent_buffer_fsid(struct extent_buffer *eb, const void *src);
  406. void write_extent_buffer_chunk_tree_uuid(struct extent_buffer *eb,
  407. const void *src);
  408. void write_extent_buffer(struct extent_buffer *eb, const void *src,
  409. unsigned long start, unsigned long len);
  410. void copy_extent_buffer_full(struct extent_buffer *dst,
  411. struct extent_buffer *src);
  412. void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
  413. unsigned long dst_offset, unsigned long src_offset,
  414. unsigned long len);
  415. void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
  416. unsigned long src_offset, unsigned long len);
  417. void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
  418. unsigned long src_offset, unsigned long len);
  419. void memzero_extent_buffer(struct extent_buffer *eb, unsigned long start,
  420. unsigned long len);
  421. int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start,
  422. unsigned long pos);
  423. void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start,
  424. unsigned long pos, unsigned long len);
  425. void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start,
  426. unsigned long pos, unsigned long len);
  427. void clear_extent_buffer_dirty(struct extent_buffer *eb);
  428. int set_extent_buffer_dirty(struct extent_buffer *eb);
  429. void set_extent_buffer_uptodate(struct extent_buffer *eb);
  430. void clear_extent_buffer_uptodate(struct extent_buffer *eb);
  431. int extent_buffer_uptodate(struct extent_buffer *eb);
  432. int extent_buffer_under_io(struct extent_buffer *eb);
  433. int map_private_extent_buffer(const struct extent_buffer *eb,
  434. unsigned long offset, unsigned long min_len,
  435. char **map, unsigned long *map_start,
  436. unsigned long *map_len);
  437. void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
  438. void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
  439. void extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end,
  440. u64 delalloc_end, struct page *locked_page,
  441. unsigned bits_to_clear,
  442. unsigned long page_ops);
  443. struct bio *btrfs_bio_alloc(struct block_device *bdev, u64 first_byte);
  444. struct bio *btrfs_io_bio_alloc(unsigned int nr_iovecs);
  445. struct bio *btrfs_bio_clone(struct bio *bio);
  446. struct bio *btrfs_bio_clone_partial(struct bio *orig, int offset, int size);
  447. struct btrfs_fs_info;
  448. struct btrfs_inode;
  449. int repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start,
  450. u64 length, u64 logical, struct page *page,
  451. unsigned int pg_offset, int mirror_num);
  452. int clean_io_failure(struct btrfs_fs_info *fs_info,
  453. struct extent_io_tree *failure_tree,
  454. struct extent_io_tree *io_tree, u64 start,
  455. struct page *page, u64 ino, unsigned int pg_offset);
  456. void end_extent_writepage(struct page *page, int err, u64 start, u64 end);
  457. int repair_eb_io_failure(struct btrfs_fs_info *fs_info,
  458. struct extent_buffer *eb, int mirror_num);
  459. /*
  460. * When IO fails, either with EIO or csum verification fails, we
  461. * try other mirrors that might have a good copy of the data. This
  462. * io_failure_record is used to record state as we go through all the
  463. * mirrors. If another mirror has good data, the page is set up to date
  464. * and things continue. If a good mirror can't be found, the original
  465. * bio end_io callback is called to indicate things have failed.
  466. */
  467. struct io_failure_record {
  468. struct page *page;
  469. u64 start;
  470. u64 len;
  471. u64 logical;
  472. unsigned long bio_flags;
  473. int this_mirror;
  474. int failed_mirror;
  475. int in_validation;
  476. };
  477. void btrfs_free_io_failure_record(struct btrfs_inode *inode, u64 start,
  478. u64 end);
  479. int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
  480. struct io_failure_record **failrec_ret);
  481. bool btrfs_check_repairable(struct inode *inode, unsigned failed_bio_pages,
  482. struct io_failure_record *failrec, int fail_mirror);
  483. struct bio *btrfs_create_repair_bio(struct inode *inode, struct bio *failed_bio,
  484. struct io_failure_record *failrec,
  485. struct page *page, int pg_offset, int icsum,
  486. bio_end_io_t *endio_func, void *data);
  487. int free_io_failure(struct extent_io_tree *failure_tree,
  488. struct extent_io_tree *io_tree,
  489. struct io_failure_record *rec);
  490. #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
  491. noinline u64 find_lock_delalloc_range(struct inode *inode,
  492. struct extent_io_tree *tree,
  493. struct page *locked_page, u64 *start,
  494. u64 *end, u64 max_bytes);
  495. #endif
  496. struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
  497. u64 start);
  498. #endif