xref: /linux/fs/btrfs/extent_io.h (revision a8fe58cec351c25e09c393bf46117c0c47b5a17c)
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_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_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 
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 #define PAGE_SET_ERROR		(1 << 5)
55 
56 /*
57  * page->private values.  Every page that is controlled by the extent
58  * map has page->private set to one.
59  */
60 #define EXTENT_PAGE_PRIVATE 1
61 
62 struct extent_state;
63 struct btrfs_root;
64 struct btrfs_io_bio;
65 
66 typedef	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);
69 struct 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 *bits);
87 	void (*clear_bit_hook)(struct inode *inode, struct extent_state *state,
88 			       unsigned *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 
96 struct 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 	const struct extent_io_ops *ops;
103 };
104 
105 struct extent_state {
106 	u64 start;
107 	u64 end; /* inclusive */
108 	struct rb_node rb_node;
109 
110 	/* ADD NEW ELEMENTS AFTER THIS */
111 	wait_queue_head_t wq;
112 	atomic_t refs;
113 	unsigned state;
114 
115 	/* for use by the FS */
116 	u64 private;
117 
118 #ifdef CONFIG_BTRFS_DEBUG
119 	struct list_head leak_list;
120 #endif
121 };
122 
123 #define INLINE_EXTENT_BUFFER_PAGES 16
124 #define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_CACHE_SIZE)
125 struct extent_buffer {
126 	u64 start;
127 	unsigned long len;
128 	unsigned long bflags;
129 	struct btrfs_fs_info *fs_info;
130 	spinlock_t refs_lock;
131 	atomic_t refs;
132 	atomic_t io_pages;
133 	int read_mirror;
134 	struct rcu_head rcu_head;
135 	pid_t lock_owner;
136 
137 	/* count of read lock holders on the extent buffer */
138 	atomic_t write_locks;
139 	atomic_t read_locks;
140 	atomic_t blocking_writers;
141 	atomic_t blocking_readers;
142 	atomic_t spinning_readers;
143 	atomic_t spinning_writers;
144 	short lock_nested;
145 	/* >= 0 if eb belongs to a log tree, -1 otherwise */
146 	short log_index;
147 
148 	/* protects write locks */
149 	rwlock_t lock;
150 
151 	/* readers use lock_wq while they wait for the write
152 	 * lock holders to unlock
153 	 */
154 	wait_queue_head_t write_lock_wq;
155 
156 	/* writers use read_lock_wq while they wait for readers
157 	 * to unlock
158 	 */
159 	wait_queue_head_t read_lock_wq;
160 	struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
161 #ifdef CONFIG_BTRFS_DEBUG
162 	struct list_head leak_list;
163 #endif
164 };
165 
166 /*
167  * Structure to record how many bytes and which ranges are set/cleared
168  */
169 struct extent_changeset {
170 	/* How many bytes are set/cleared in this operation */
171 	u64 bytes_changed;
172 
173 	/* Changed ranges */
174 	struct ulist *range_changed;
175 };
176 
177 static inline void extent_set_compress_type(unsigned long *bio_flags,
178 					    int compress_type)
179 {
180 	*bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT;
181 }
182 
183 static inline int extent_compress_type(unsigned long bio_flags)
184 {
185 	return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
186 }
187 
188 struct extent_map_tree;
189 
190 typedef struct extent_map *(get_extent_t)(struct inode *inode,
191 					  struct page *page,
192 					  size_t pg_offset,
193 					  u64 start, u64 len,
194 					  int create);
195 
196 void extent_io_tree_init(struct extent_io_tree *tree,
197 			 struct address_space *mapping);
198 int try_release_extent_mapping(struct extent_map_tree *map,
199 			       struct extent_io_tree *tree, struct page *page,
200 			       gfp_t mask);
201 int try_release_extent_buffer(struct page *page);
202 int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
203 		     struct extent_state **cached);
204 
205 static inline int lock_extent(struct extent_io_tree *tree, u64 start, u64 end)
206 {
207 	return lock_extent_bits(tree, start, end, NULL);
208 }
209 
210 int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
211 int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
212 			  get_extent_t *get_extent, int mirror_num);
213 int extent_read_full_page_nolock(struct extent_io_tree *tree, struct page *page,
214 				 get_extent_t *get_extent, int mirror_num);
215 int __init extent_io_init(void);
216 void extent_io_exit(void);
217 
218 u64 count_range_bits(struct extent_io_tree *tree,
219 		     u64 *start, u64 search_end,
220 		     u64 max_bytes, unsigned bits, int contig);
221 
222 void free_extent_state(struct extent_state *state);
223 int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
224 		   unsigned bits, int filled,
225 		   struct extent_state *cached_state);
226 int clear_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
227 			     unsigned bits, gfp_t mask,
228 			     struct extent_changeset *changeset);
229 int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
230 		     unsigned bits, int wake, int delete,
231 		     struct extent_state **cached, gfp_t mask);
232 
233 static inline int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end)
234 {
235 	return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL,
236 				GFP_NOFS);
237 }
238 
239 static inline int unlock_extent_cached(struct extent_io_tree *tree, u64 start,
240 		u64 end, struct extent_state **cached, gfp_t mask)
241 {
242 	return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
243 				mask);
244 }
245 
246 static inline int clear_extent_bits(struct extent_io_tree *tree, u64 start,
247 		u64 end, unsigned bits, gfp_t mask)
248 {
249 	int wake = 0;
250 
251 	if (bits & EXTENT_LOCKED)
252 		wake = 1;
253 
254 	return clear_extent_bit(tree, start, end, bits, wake, 0, NULL, mask);
255 }
256 
257 int set_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
258 			   unsigned bits, gfp_t mask,
259 			   struct extent_changeset *changeset);
260 int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
261 		   unsigned bits, u64 *failed_start,
262 		   struct extent_state **cached_state, gfp_t mask);
263 
264 static inline int set_extent_bits(struct extent_io_tree *tree, u64 start,
265 		u64 end, unsigned bits, gfp_t mask)
266 {
267 	return set_extent_bit(tree, start, end, bits, NULL, NULL, mask);
268 }
269 
270 static inline int clear_extent_uptodate(struct extent_io_tree *tree, u64 start,
271 		u64 end, struct extent_state **cached_state, gfp_t mask)
272 {
273 	return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0,
274 				cached_state, mask);
275 }
276 
277 static inline int set_extent_dirty(struct extent_io_tree *tree, u64 start,
278 		u64 end, gfp_t mask)
279 {
280 	return set_extent_bit(tree, start, end, EXTENT_DIRTY, NULL,
281 			      NULL, mask);
282 }
283 
284 static inline int clear_extent_dirty(struct extent_io_tree *tree, u64 start,
285 		u64 end, gfp_t mask)
286 {
287 	return clear_extent_bit(tree, start, end,
288 				EXTENT_DIRTY | EXTENT_DELALLOC |
289 				EXTENT_DO_ACCOUNTING, 0, 0, NULL, mask);
290 }
291 
292 int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
293 		       unsigned bits, unsigned clear_bits,
294 		       struct extent_state **cached_state, gfp_t mask);
295 
296 static inline int set_extent_delalloc(struct extent_io_tree *tree, u64 start,
297 		u64 end, struct extent_state **cached_state, gfp_t mask)
298 {
299 	return set_extent_bit(tree, start, end,
300 			      EXTENT_DELALLOC | EXTENT_UPTODATE,
301 			      NULL, cached_state, mask);
302 }
303 
304 static inline int set_extent_defrag(struct extent_io_tree *tree, u64 start,
305 		u64 end, struct extent_state **cached_state, gfp_t mask)
306 {
307 	return set_extent_bit(tree, start, end,
308 			      EXTENT_DELALLOC | EXTENT_UPTODATE | EXTENT_DEFRAG,
309 			      NULL, cached_state, mask);
310 }
311 
312 static inline int set_extent_new(struct extent_io_tree *tree, u64 start,
313 		u64 end, gfp_t mask)
314 {
315 	return set_extent_bit(tree, start, end, EXTENT_NEW, NULL, NULL, mask);
316 }
317 
318 static inline int set_extent_uptodate(struct extent_io_tree *tree, u64 start,
319 		u64 end, struct extent_state **cached_state, gfp_t mask)
320 {
321 	return set_extent_bit(tree, start, end, EXTENT_UPTODATE, NULL,
322 			      cached_state, mask);
323 }
324 
325 int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
326 			  u64 *start_ret, u64 *end_ret, unsigned bits,
327 			  struct extent_state **cached_state);
328 int extent_invalidatepage(struct extent_io_tree *tree,
329 			  struct page *page, unsigned long offset);
330 int extent_write_full_page(struct extent_io_tree *tree, struct page *page,
331 			  get_extent_t *get_extent,
332 			  struct writeback_control *wbc);
333 int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode,
334 			      u64 start, u64 end, get_extent_t *get_extent,
335 			      int mode);
336 int extent_writepages(struct extent_io_tree *tree,
337 		      struct address_space *mapping,
338 		      get_extent_t *get_extent,
339 		      struct writeback_control *wbc);
340 int btree_write_cache_pages(struct address_space *mapping,
341 			    struct writeback_control *wbc);
342 int extent_readpages(struct extent_io_tree *tree,
343 		     struct address_space *mapping,
344 		     struct list_head *pages, unsigned nr_pages,
345 		     get_extent_t get_extent);
346 int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
347 		__u64 start, __u64 len, get_extent_t *get_extent);
348 int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private);
349 void set_page_extent_mapped(struct page *page);
350 
351 struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
352 					  u64 start);
353 struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
354 						  u64 start, unsigned long len);
355 struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
356 						u64 start);
357 struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
358 struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
359 					 u64 start);
360 void free_extent_buffer(struct extent_buffer *eb);
361 void free_extent_buffer_stale(struct extent_buffer *eb);
362 #define WAIT_NONE	0
363 #define WAIT_COMPLETE	1
364 #define WAIT_PAGE_LOCK	2
365 int read_extent_buffer_pages(struct extent_io_tree *tree,
366 			     struct extent_buffer *eb, u64 start, int wait,
367 			     get_extent_t *get_extent, int mirror_num);
368 void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
369 
370 static inline unsigned long num_extent_pages(u64 start, u64 len)
371 {
372 	return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) -
373 		(start >> PAGE_CACHE_SHIFT);
374 }
375 
376 static inline void extent_buffer_get(struct extent_buffer *eb)
377 {
378 	atomic_inc(&eb->refs);
379 }
380 
381 int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
382 			  unsigned long start,
383 			  unsigned long len);
384 void read_extent_buffer(struct extent_buffer *eb, void *dst,
385 			unsigned long start,
386 			unsigned long len);
387 int read_extent_buffer_to_user(struct extent_buffer *eb, void __user *dst,
388 			       unsigned long start,
389 			       unsigned long len);
390 void write_extent_buffer(struct extent_buffer *eb, const void *src,
391 			 unsigned long start, unsigned long len);
392 void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
393 			unsigned long dst_offset, unsigned long src_offset,
394 			unsigned long len);
395 void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
396 			   unsigned long src_offset, unsigned long len);
397 void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
398 			   unsigned long src_offset, unsigned long len);
399 void memset_extent_buffer(struct extent_buffer *eb, char c,
400 			  unsigned long start, unsigned long len);
401 int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start,
402 			   unsigned long pos);
403 void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start,
404 			      unsigned long pos, unsigned long len);
405 void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start,
406 				unsigned long pos, unsigned long len);
407 void clear_extent_buffer_dirty(struct extent_buffer *eb);
408 int set_extent_buffer_dirty(struct extent_buffer *eb);
409 void set_extent_buffer_uptodate(struct extent_buffer *eb);
410 void clear_extent_buffer_uptodate(struct extent_buffer *eb);
411 int extent_buffer_uptodate(struct extent_buffer *eb);
412 int extent_buffer_under_io(struct extent_buffer *eb);
413 int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
414 		      unsigned long min_len, char **map,
415 		      unsigned long *map_start,
416 		      unsigned long *map_len);
417 void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
418 void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
419 void extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end,
420 				 struct page *locked_page,
421 				 unsigned bits_to_clear,
422 				 unsigned long page_ops);
423 struct bio *
424 btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
425 		gfp_t gfp_flags);
426 struct bio *btrfs_io_bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs);
427 struct bio *btrfs_bio_clone(struct bio *bio, gfp_t gfp_mask);
428 
429 struct btrfs_fs_info;
430 
431 int repair_io_failure(struct inode *inode, u64 start, u64 length, u64 logical,
432 		      struct page *page, unsigned int pg_offset,
433 		      int mirror_num);
434 int clean_io_failure(struct inode *inode, u64 start, struct page *page,
435 		     unsigned int pg_offset);
436 void end_extent_writepage(struct page *page, int err, u64 start, u64 end);
437 int repair_eb_io_failure(struct btrfs_root *root, struct extent_buffer *eb,
438 			 int mirror_num);
439 
440 /*
441  * When IO fails, either with EIO or csum verification fails, we
442  * try other mirrors that might have a good copy of the data.  This
443  * io_failure_record is used to record state as we go through all the
444  * mirrors.  If another mirror has good data, the page is set up to date
445  * and things continue.  If a good mirror can't be found, the original
446  * bio end_io callback is called to indicate things have failed.
447  */
448 struct io_failure_record {
449 	struct page *page;
450 	u64 start;
451 	u64 len;
452 	u64 logical;
453 	unsigned long bio_flags;
454 	int this_mirror;
455 	int failed_mirror;
456 	int in_validation;
457 };
458 
459 void btrfs_free_io_failure_record(struct inode *inode, u64 start, u64 end);
460 int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
461 				struct io_failure_record **failrec_ret);
462 int btrfs_check_repairable(struct inode *inode, struct bio *failed_bio,
463 			   struct io_failure_record *failrec, int fail_mirror);
464 struct bio *btrfs_create_repair_bio(struct inode *inode, struct bio *failed_bio,
465 				    struct io_failure_record *failrec,
466 				    struct page *page, int pg_offset, int icsum,
467 				    bio_end_io_t *endio_func, void *data);
468 int free_io_failure(struct inode *inode, struct io_failure_record *rec);
469 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
470 noinline u64 find_lock_delalloc_range(struct inode *inode,
471 				      struct extent_io_tree *tree,
472 				      struct page *locked_page, u64 *start,
473 				      u64 *end, u64 max_bytes);
474 #endif
475 struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
476 					       u64 start);
477 #endif
478