xref: /linux/fs/btrfs/extent_io.h (revision c0c914eca7f251c70facc37dfebeaf176601918d)
1 #ifndef __EXTENTIO__
2 #define __EXTENTIO__
3 
4 #include <linux/rbtree.h>
5 #include "ulist.h"
6 
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_DO_ACCOUNTING	(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_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_FLAG_SHIFT 16
33 
34 /* these are bit numbers for test/set bit */
35 #define EXTENT_BUFFER_UPTODATE 0
36 #define EXTENT_BUFFER_DIRTY 2
37 #define EXTENT_BUFFER_CORRUPT 3
38 #define EXTENT_BUFFER_READAHEAD 4	/* this got triggered by readahead */
39 #define EXTENT_BUFFER_TREE_REF 5
40 #define EXTENT_BUFFER_STALE 6
41 #define EXTENT_BUFFER_WRITEBACK 7
42 #define EXTENT_BUFFER_READ_ERR 8        /* read IO error */
43 #define EXTENT_BUFFER_DUMMY 9
44 #define EXTENT_BUFFER_IN_TREE 10
45 #define EXTENT_BUFFER_WRITE_ERR 11    /* write IO error */
46 
47 /* these are flags for extent_clear_unlock_delalloc */
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 
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 struct extent_state;
62 struct btrfs_root;
63 struct btrfs_io_bio;
64 
65 typedef	int (extent_submit_bio_hook_t)(struct inode *inode, int rw,
66 				       struct bio *bio, int mirror_num,
67 				       unsigned long bio_flags, u64 bio_offset);
68 struct extent_io_ops {
69 	int (*fill_delalloc)(struct inode *inode, struct page *locked_page,
70 			     u64 start, u64 end, int *page_started,
71 			     unsigned long *nr_written);
72 	int (*writepage_start_hook)(struct page *page, u64 start, u64 end);
73 	int (*writepage_io_hook)(struct page *page, u64 start, u64 end);
74 	extent_submit_bio_hook_t *submit_bio_hook;
75 	int (*merge_bio_hook)(int rw, struct page *page, unsigned long offset,
76 			      size_t size, struct bio *bio,
77 			      unsigned long bio_flags);
78 	int (*readpage_io_failed_hook)(struct page *page, int failed_mirror);
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 	int (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
83 				      struct extent_state *state, int uptodate);
84 	void (*set_bit_hook)(struct inode *inode, struct extent_state *state,
85 			     unsigned *bits);
86 	void (*clear_bit_hook)(struct inode *inode, struct extent_state *state,
87 			       unsigned *bits);
88 	void (*merge_extent_hook)(struct inode *inode,
89 				  struct extent_state *new,
90 				  struct extent_state *other);
91 	void (*split_extent_hook)(struct inode *inode,
92 				  struct extent_state *orig, u64 split);
93 };
94 
95 struct extent_io_tree {
96 	struct rb_root state;
97 	struct address_space *mapping;
98 	u64 dirty_bytes;
99 	int track_uptodate;
100 	spinlock_t lock;
101 	const struct extent_io_ops *ops;
102 };
103 
104 struct extent_state {
105 	u64 start;
106 	u64 end; /* inclusive */
107 	struct rb_node rb_node;
108 
109 	/* ADD NEW ELEMENTS AFTER THIS */
110 	wait_queue_head_t wq;
111 	atomic_t refs;
112 	unsigned state;
113 
114 	/* for use by the FS */
115 	u64 private;
116 
117 #ifdef CONFIG_BTRFS_DEBUG
118 	struct list_head leak_list;
119 #endif
120 };
121 
122 #define INLINE_EXTENT_BUFFER_PAGES 16
123 #define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_CACHE_SIZE)
124 struct extent_buffer {
125 	u64 start;
126 	unsigned long len;
127 	unsigned long bflags;
128 	struct btrfs_fs_info *fs_info;
129 	spinlock_t refs_lock;
130 	atomic_t refs;
131 	atomic_t io_pages;
132 	int read_mirror;
133 	struct rcu_head rcu_head;
134 	pid_t lock_owner;
135 
136 	/* count of read lock holders on the extent buffer */
137 	atomic_t write_locks;
138 	atomic_t read_locks;
139 	atomic_t blocking_writers;
140 	atomic_t blocking_readers;
141 	atomic_t spinning_readers;
142 	atomic_t spinning_writers;
143 	short lock_nested;
144 	/* >= 0 if eb belongs to a log tree, -1 otherwise */
145 	short log_index;
146 
147 	/* protects write locks */
148 	rwlock_t lock;
149 
150 	/* readers use lock_wq while they wait for the write
151 	 * lock holders to unlock
152 	 */
153 	wait_queue_head_t write_lock_wq;
154 
155 	/* writers use read_lock_wq while they wait for readers
156 	 * to unlock
157 	 */
158 	wait_queue_head_t read_lock_wq;
159 	struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
160 #ifdef CONFIG_BTRFS_DEBUG
161 	struct list_head leak_list;
162 #endif
163 };
164 
165 /*
166  * Structure to record how many bytes and which ranges are set/cleared
167  */
168 struct extent_changeset {
169 	/* How many bytes are set/cleared in this operation */
170 	u64 bytes_changed;
171 
172 	/* Changed ranges */
173 	struct ulist *range_changed;
174 };
175 
176 static 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 
182 static inline int extent_compress_type(unsigned long bio_flags)
183 {
184 	return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
185 }
186 
187 struct extent_map_tree;
188 
189 typedef struct extent_map *(get_extent_t)(struct inode *inode,
190 					  struct page *page,
191 					  size_t pg_offset,
192 					  u64 start, u64 len,
193 					  int create);
194 
195 void extent_io_tree_init(struct extent_io_tree *tree,
196 			 struct address_space *mapping);
197 int try_release_extent_mapping(struct extent_map_tree *map,
198 			       struct extent_io_tree *tree, struct page *page,
199 			       gfp_t mask);
200 int try_release_extent_buffer(struct page *page);
201 int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
202 		     struct extent_state **cached);
203 
204 static inline int lock_extent(struct extent_io_tree *tree, u64 start, u64 end)
205 {
206 	return lock_extent_bits(tree, start, end, NULL);
207 }
208 
209 int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
210 int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
211 			  get_extent_t *get_extent, int mirror_num);
212 int __init extent_io_init(void);
213 void extent_io_exit(void);
214 
215 u64 count_range_bits(struct extent_io_tree *tree,
216 		     u64 *start, u64 search_end,
217 		     u64 max_bytes, unsigned bits, int contig);
218 
219 void free_extent_state(struct extent_state *state);
220 int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
221 		   unsigned bits, int filled,
222 		   struct extent_state *cached_state);
223 int clear_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
224 			     unsigned bits, gfp_t mask,
225 			     struct extent_changeset *changeset);
226 int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
227 		     unsigned bits, int wake, int delete,
228 		     struct extent_state **cached, gfp_t mask);
229 
230 static inline int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end)
231 {
232 	return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL,
233 				GFP_NOFS);
234 }
235 
236 static inline int unlock_extent_cached(struct extent_io_tree *tree, u64 start,
237 		u64 end, struct extent_state **cached, gfp_t mask)
238 {
239 	return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
240 				mask);
241 }
242 
243 static inline int clear_extent_bits(struct extent_io_tree *tree, u64 start,
244 		u64 end, unsigned bits, gfp_t mask)
245 {
246 	int wake = 0;
247 
248 	if (bits & EXTENT_LOCKED)
249 		wake = 1;
250 
251 	return clear_extent_bit(tree, start, end, bits, wake, 0, NULL, mask);
252 }
253 
254 int set_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
255 			   unsigned bits, gfp_t mask,
256 			   struct extent_changeset *changeset);
257 int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
258 		   unsigned bits, u64 *failed_start,
259 		   struct extent_state **cached_state, gfp_t mask);
260 
261 static inline int set_extent_bits(struct extent_io_tree *tree, u64 start,
262 		u64 end, unsigned bits, gfp_t mask)
263 {
264 	return set_extent_bit(tree, start, end, bits, NULL, NULL, mask);
265 }
266 
267 static inline int clear_extent_uptodate(struct extent_io_tree *tree, u64 start,
268 		u64 end, struct extent_state **cached_state, gfp_t mask)
269 {
270 	return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0,
271 				cached_state, mask);
272 }
273 
274 static inline int set_extent_dirty(struct extent_io_tree *tree, u64 start,
275 		u64 end, gfp_t mask)
276 {
277 	return set_extent_bit(tree, start, end, EXTENT_DIRTY, NULL,
278 			      NULL, mask);
279 }
280 
281 static inline int clear_extent_dirty(struct extent_io_tree *tree, u64 start,
282 		u64 end, gfp_t mask)
283 {
284 	return clear_extent_bit(tree, start, end,
285 				EXTENT_DIRTY | EXTENT_DELALLOC |
286 				EXTENT_DO_ACCOUNTING, 0, 0, NULL, mask);
287 }
288 
289 int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
290 		       unsigned bits, unsigned clear_bits,
291 		       struct extent_state **cached_state, gfp_t mask);
292 
293 static inline int set_extent_delalloc(struct extent_io_tree *tree, u64 start,
294 		u64 end, struct extent_state **cached_state, gfp_t mask)
295 {
296 	return set_extent_bit(tree, start, end,
297 			      EXTENT_DELALLOC | EXTENT_UPTODATE,
298 			      NULL, cached_state, mask);
299 }
300 
301 static inline int set_extent_defrag(struct extent_io_tree *tree, u64 start,
302 		u64 end, struct extent_state **cached_state, gfp_t mask)
303 {
304 	return set_extent_bit(tree, start, end,
305 			      EXTENT_DELALLOC | EXTENT_UPTODATE | EXTENT_DEFRAG,
306 			      NULL, cached_state, mask);
307 }
308 
309 static inline int set_extent_new(struct extent_io_tree *tree, u64 start,
310 		u64 end, gfp_t mask)
311 {
312 	return set_extent_bit(tree, start, end, EXTENT_NEW, NULL, NULL, mask);
313 }
314 
315 static inline int set_extent_uptodate(struct extent_io_tree *tree, u64 start,
316 		u64 end, struct extent_state **cached_state, gfp_t mask)
317 {
318 	return set_extent_bit(tree, start, end, EXTENT_UPTODATE, NULL,
319 			      cached_state, mask);
320 }
321 
322 int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
323 			  u64 *start_ret, u64 *end_ret, unsigned bits,
324 			  struct extent_state **cached_state);
325 int extent_invalidatepage(struct extent_io_tree *tree,
326 			  struct page *page, unsigned long offset);
327 int extent_write_full_page(struct extent_io_tree *tree, struct page *page,
328 			  get_extent_t *get_extent,
329 			  struct writeback_control *wbc);
330 int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode,
331 			      u64 start, u64 end, get_extent_t *get_extent,
332 			      int mode);
333 int extent_writepages(struct extent_io_tree *tree,
334 		      struct address_space *mapping,
335 		      get_extent_t *get_extent,
336 		      struct writeback_control *wbc);
337 int btree_write_cache_pages(struct address_space *mapping,
338 			    struct writeback_control *wbc);
339 int extent_readpages(struct extent_io_tree *tree,
340 		     struct address_space *mapping,
341 		     struct list_head *pages, unsigned nr_pages,
342 		     get_extent_t get_extent);
343 int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
344 		__u64 start, __u64 len, get_extent_t *get_extent);
345 int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private);
346 void set_page_extent_mapped(struct page *page);
347 
348 struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
349 					  u64 start);
350 struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
351 						  u64 start, unsigned long len);
352 struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
353 						u64 start);
354 struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
355 struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
356 					 u64 start);
357 void free_extent_buffer(struct extent_buffer *eb);
358 void free_extent_buffer_stale(struct extent_buffer *eb);
359 #define WAIT_NONE	0
360 #define WAIT_COMPLETE	1
361 #define WAIT_PAGE_LOCK	2
362 int read_extent_buffer_pages(struct extent_io_tree *tree,
363 			     struct extent_buffer *eb, u64 start, int wait,
364 			     get_extent_t *get_extent, int mirror_num);
365 void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
366 
367 static inline unsigned long num_extent_pages(u64 start, u64 len)
368 {
369 	return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) -
370 		(start >> PAGE_CACHE_SHIFT);
371 }
372 
373 static inline void extent_buffer_get(struct extent_buffer *eb)
374 {
375 	atomic_inc(&eb->refs);
376 }
377 
378 int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
379 			  unsigned long start,
380 			  unsigned long len);
381 void read_extent_buffer(struct extent_buffer *eb, void *dst,
382 			unsigned long start,
383 			unsigned long len);
384 int read_extent_buffer_to_user(struct extent_buffer *eb, void __user *dst,
385 			       unsigned long start,
386 			       unsigned long len);
387 void write_extent_buffer(struct extent_buffer *eb, const void *src,
388 			 unsigned long start, unsigned long len);
389 void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
390 			unsigned long dst_offset, unsigned long src_offset,
391 			unsigned long len);
392 void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
393 			   unsigned long src_offset, unsigned long len);
394 void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
395 			   unsigned long src_offset, unsigned long len);
396 void memset_extent_buffer(struct extent_buffer *eb, char c,
397 			  unsigned long start, unsigned long len);
398 int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start,
399 			   unsigned long pos);
400 void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start,
401 			      unsigned long pos, unsigned long len);
402 void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start,
403 				unsigned long pos, unsigned long len);
404 void clear_extent_buffer_dirty(struct extent_buffer *eb);
405 int set_extent_buffer_dirty(struct extent_buffer *eb);
406 void set_extent_buffer_uptodate(struct extent_buffer *eb);
407 void clear_extent_buffer_uptodate(struct extent_buffer *eb);
408 int extent_buffer_uptodate(struct extent_buffer *eb);
409 int extent_buffer_under_io(struct extent_buffer *eb);
410 int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
411 		      unsigned long min_len, char **map,
412 		      unsigned long *map_start,
413 		      unsigned long *map_len);
414 void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
415 void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
416 void extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end,
417 				 struct page *locked_page,
418 				 unsigned bits_to_clear,
419 				 unsigned long page_ops);
420 struct bio *
421 btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
422 		gfp_t gfp_flags);
423 struct bio *btrfs_io_bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs);
424 struct bio *btrfs_bio_clone(struct bio *bio, gfp_t gfp_mask);
425 
426 struct btrfs_fs_info;
427 
428 int repair_io_failure(struct inode *inode, u64 start, u64 length, u64 logical,
429 		      struct page *page, unsigned int pg_offset,
430 		      int mirror_num);
431 int clean_io_failure(struct inode *inode, u64 start, struct page *page,
432 		     unsigned int pg_offset);
433 void end_extent_writepage(struct page *page, int err, u64 start, u64 end);
434 int repair_eb_io_failure(struct btrfs_root *root, struct extent_buffer *eb,
435 			 int mirror_num);
436 
437 /*
438  * When IO fails, either with EIO or csum verification fails, we
439  * try other mirrors that might have a good copy of the data.  This
440  * io_failure_record is used to record state as we go through all the
441  * mirrors.  If another mirror has good data, the page is set up to date
442  * and things continue.  If a good mirror can't be found, the original
443  * bio end_io callback is called to indicate things have failed.
444  */
445 struct io_failure_record {
446 	struct page *page;
447 	u64 start;
448 	u64 len;
449 	u64 logical;
450 	unsigned long bio_flags;
451 	int this_mirror;
452 	int failed_mirror;
453 	int in_validation;
454 };
455 
456 void btrfs_free_io_failure_record(struct inode *inode, u64 start, u64 end);
457 int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
458 				struct io_failure_record **failrec_ret);
459 int btrfs_check_repairable(struct inode *inode, struct bio *failed_bio,
460 			   struct io_failure_record *failrec, int fail_mirror);
461 struct bio *btrfs_create_repair_bio(struct inode *inode, struct bio *failed_bio,
462 				    struct io_failure_record *failrec,
463 				    struct page *page, int pg_offset, int icsum,
464 				    bio_end_io_t *endio_func, void *data);
465 int free_io_failure(struct inode *inode, struct io_failure_record *rec);
466 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
467 noinline u64 find_lock_delalloc_range(struct inode *inode,
468 				      struct extent_io_tree *tree,
469 				      struct page *locked_page, u64 *start,
470 				      u64 *end, u64 max_bytes);
471 #endif
472 struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
473 					       u64 start);
474 #endif
475