xref: /openbmc/linux/fs/btrfs/extent_io.h (revision 78700c0a)
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 struct io_failure_record;
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 	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 	struct io_failure_record *failrec;
115 
116 #ifdef CONFIG_BTRFS_DEBUG
117 	struct list_head leak_list;
118 #endif
119 };
120 
121 #define INLINE_EXTENT_BUFFER_PAGES 16
122 #define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_SIZE)
123 struct extent_buffer {
124 	u64 start;
125 	unsigned long len;
126 	unsigned long bflags;
127 	struct btrfs_fs_info *fs_info;
128 	spinlock_t refs_lock;
129 	atomic_t refs;
130 	atomic_t io_pages;
131 	int read_mirror;
132 	struct rcu_head rcu_head;
133 	pid_t lock_owner;
134 
135 	/* count of read lock holders on the extent buffer */
136 	atomic_t write_locks;
137 	atomic_t read_locks;
138 	atomic_t blocking_writers;
139 	atomic_t blocking_readers;
140 	atomic_t spinning_readers;
141 	atomic_t spinning_writers;
142 	short lock_nested;
143 	/* >= 0 if eb belongs to a log tree, -1 otherwise */
144 	short log_index;
145 
146 	/* protects write locks */
147 	rwlock_t lock;
148 
149 	/* readers use lock_wq while they wait for the write
150 	 * lock holders to unlock
151 	 */
152 	wait_queue_head_t write_lock_wq;
153 
154 	/* writers use read_lock_wq while they wait for readers
155 	 * to unlock
156 	 */
157 	wait_queue_head_t read_lock_wq;
158 	struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
159 #ifdef CONFIG_BTRFS_DEBUG
160 	struct list_head leak_list;
161 #endif
162 };
163 
164 /*
165  * Structure to record how many bytes and which ranges are set/cleared
166  */
167 struct extent_changeset {
168 	/* How many bytes are set/cleared in this operation */
169 	u64 bytes_changed;
170 
171 	/* Changed ranges */
172 	struct ulist *range_changed;
173 };
174 
175 static inline void extent_set_compress_type(unsigned long *bio_flags,
176 					    int compress_type)
177 {
178 	*bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT;
179 }
180 
181 static inline int extent_compress_type(unsigned long bio_flags)
182 {
183 	return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
184 }
185 
186 struct extent_map_tree;
187 
188 typedef struct extent_map *(get_extent_t)(struct inode *inode,
189 					  struct page *page,
190 					  size_t pg_offset,
191 					  u64 start, u64 len,
192 					  int create);
193 
194 void extent_io_tree_init(struct extent_io_tree *tree,
195 			 struct address_space *mapping);
196 int try_release_extent_mapping(struct extent_map_tree *map,
197 			       struct extent_io_tree *tree, struct page *page,
198 			       gfp_t mask);
199 int try_release_extent_buffer(struct page *page);
200 int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
201 		     struct extent_state **cached);
202 
203 static inline int lock_extent(struct extent_io_tree *tree, u64 start, u64 end)
204 {
205 	return lock_extent_bits(tree, start, end, NULL);
206 }
207 
208 int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
209 int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
210 			  get_extent_t *get_extent, int mirror_num);
211 int __init extent_io_init(void);
212 void extent_io_exit(void);
213 
214 u64 count_range_bits(struct extent_io_tree *tree,
215 		     u64 *start, u64 search_end,
216 		     u64 max_bytes, unsigned bits, int contig);
217 
218 void free_extent_state(struct extent_state *state);
219 int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
220 		   unsigned bits, int filled,
221 		   struct extent_state *cached_state);
222 int clear_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
223 		unsigned bits, struct extent_changeset *changeset);
224 int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
225 		     unsigned bits, int wake, int delete,
226 		     struct extent_state **cached, gfp_t mask);
227 
228 static inline int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end)
229 {
230 	return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL,
231 				GFP_NOFS);
232 }
233 
234 static inline int unlock_extent_cached(struct extent_io_tree *tree, u64 start,
235 		u64 end, struct extent_state **cached, gfp_t mask)
236 {
237 	return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
238 				mask);
239 }
240 
241 static inline int clear_extent_bits(struct extent_io_tree *tree, u64 start,
242 		u64 end, unsigned bits)
243 {
244 	int wake = 0;
245 
246 	if (bits & EXTENT_LOCKED)
247 		wake = 1;
248 
249 	return clear_extent_bit(tree, start, end, bits, wake, 0, NULL,
250 			GFP_NOFS);
251 }
252 
253 int set_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
254 			   unsigned bits, struct extent_changeset *changeset);
255 int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
256 		   unsigned bits, u64 *failed_start,
257 		   struct extent_state **cached_state, gfp_t mask);
258 
259 static inline int set_extent_bits(struct extent_io_tree *tree, u64 start,
260 		u64 end, unsigned bits)
261 {
262 	return set_extent_bit(tree, start, end, bits, NULL, NULL, GFP_NOFS);
263 }
264 
265 static inline int clear_extent_uptodate(struct extent_io_tree *tree, u64 start,
266 		u64 end, struct extent_state **cached_state, gfp_t mask)
267 {
268 	return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0,
269 				cached_state, mask);
270 }
271 
272 static inline int set_extent_dirty(struct extent_io_tree *tree, u64 start,
273 		u64 end, gfp_t mask)
274 {
275 	return set_extent_bit(tree, start, end, EXTENT_DIRTY, NULL,
276 			      NULL, mask);
277 }
278 
279 static inline int clear_extent_dirty(struct extent_io_tree *tree, u64 start,
280 		u64 end)
281 {
282 	return clear_extent_bit(tree, start, end,
283 				EXTENT_DIRTY | EXTENT_DELALLOC |
284 				EXTENT_DO_ACCOUNTING, 0, 0, NULL, GFP_NOFS);
285 }
286 
287 int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
288 		       unsigned bits, unsigned clear_bits,
289 		       struct extent_state **cached_state);
290 
291 static inline int set_extent_delalloc(struct extent_io_tree *tree, u64 start,
292 		u64 end, struct extent_state **cached_state)
293 {
294 	return set_extent_bit(tree, start, end,
295 			      EXTENT_DELALLOC | EXTENT_UPTODATE,
296 			      NULL, cached_state, GFP_NOFS);
297 }
298 
299 static inline int set_extent_defrag(struct extent_io_tree *tree, u64 start,
300 		u64 end, struct extent_state **cached_state)
301 {
302 	return set_extent_bit(tree, start, end,
303 			      EXTENT_DELALLOC | EXTENT_UPTODATE | EXTENT_DEFRAG,
304 			      NULL, cached_state, GFP_NOFS);
305 }
306 
307 static inline int set_extent_new(struct extent_io_tree *tree, u64 start,
308 		u64 end)
309 {
310 	return set_extent_bit(tree, start, end, EXTENT_NEW, NULL, NULL,
311 			GFP_NOFS);
312 }
313 
314 static inline int set_extent_uptodate(struct extent_io_tree *tree, u64 start,
315 		u64 end, struct extent_state **cached_state, gfp_t mask)
316 {
317 	return set_extent_bit(tree, start, end, EXTENT_UPTODATE, NULL,
318 			      cached_state, mask);
319 }
320 
321 int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
322 			  u64 *start_ret, u64 *end_ret, unsigned bits,
323 			  struct extent_state **cached_state);
324 int extent_invalidatepage(struct extent_io_tree *tree,
325 			  struct page *page, unsigned long offset);
326 int extent_write_full_page(struct extent_io_tree *tree, struct page *page,
327 			  get_extent_t *get_extent,
328 			  struct writeback_control *wbc);
329 int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode,
330 			      u64 start, u64 end, get_extent_t *get_extent,
331 			      int mode);
332 int extent_writepages(struct extent_io_tree *tree,
333 		      struct address_space *mapping,
334 		      get_extent_t *get_extent,
335 		      struct writeback_control *wbc);
336 int btree_write_cache_pages(struct address_space *mapping,
337 			    struct writeback_control *wbc);
338 int extent_readpages(struct extent_io_tree *tree,
339 		     struct address_space *mapping,
340 		     struct list_head *pages, unsigned nr_pages,
341 		     get_extent_t get_extent);
342 int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
343 		__u64 start, __u64 len, get_extent_t *get_extent);
344 void set_page_extent_mapped(struct page *page);
345 
346 struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
347 					  u64 start);
348 struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
349 						  u64 start, unsigned long len);
350 struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
351 						u64 start);
352 struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
353 struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
354 					 u64 start);
355 void free_extent_buffer(struct extent_buffer *eb);
356 void free_extent_buffer_stale(struct extent_buffer *eb);
357 #define WAIT_NONE	0
358 #define WAIT_COMPLETE	1
359 #define WAIT_PAGE_LOCK	2
360 int read_extent_buffer_pages(struct extent_io_tree *tree,
361 			     struct extent_buffer *eb, u64 start, int wait,
362 			     get_extent_t *get_extent, int mirror_num);
363 void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
364 
365 static inline unsigned long num_extent_pages(u64 start, u64 len)
366 {
367 	return ((start + len + PAGE_SIZE - 1) >> PAGE_SHIFT) -
368 		(start >> PAGE_SHIFT);
369 }
370 
371 static inline void extent_buffer_get(struct extent_buffer *eb)
372 {
373 	atomic_inc(&eb->refs);
374 }
375 
376 int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
377 			  unsigned long start,
378 			  unsigned long len);
379 void read_extent_buffer(struct extent_buffer *eb, void *dst,
380 			unsigned long start,
381 			unsigned long len);
382 int read_extent_buffer_to_user(struct extent_buffer *eb, void __user *dst,
383 			       unsigned long start,
384 			       unsigned long len);
385 void write_extent_buffer(struct extent_buffer *eb, const void *src,
386 			 unsigned long start, unsigned long len);
387 void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
388 			unsigned long dst_offset, unsigned long src_offset,
389 			unsigned long len);
390 void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
391 			   unsigned long src_offset, unsigned long len);
392 void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
393 			   unsigned long src_offset, unsigned long len);
394 void memset_extent_buffer(struct extent_buffer *eb, char c,
395 			  unsigned long start, unsigned long len);
396 int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start,
397 			   unsigned long pos);
398 void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start,
399 			      unsigned long pos, unsigned long len);
400 void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start,
401 				unsigned long pos, unsigned long len);
402 void clear_extent_buffer_dirty(struct extent_buffer *eb);
403 int set_extent_buffer_dirty(struct extent_buffer *eb);
404 void set_extent_buffer_uptodate(struct extent_buffer *eb);
405 void clear_extent_buffer_uptodate(struct extent_buffer *eb);
406 int extent_buffer_uptodate(struct extent_buffer *eb);
407 int extent_buffer_under_io(struct extent_buffer *eb);
408 int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
409 		      unsigned long min_len, char **map,
410 		      unsigned long *map_start,
411 		      unsigned long *map_len);
412 void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
413 void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
414 void extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end,
415 				 struct page *locked_page,
416 				 unsigned bits_to_clear,
417 				 unsigned long page_ops);
418 struct bio *
419 btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
420 		gfp_t gfp_flags);
421 struct bio *btrfs_io_bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs);
422 struct bio *btrfs_bio_clone(struct bio *bio, gfp_t gfp_mask);
423 
424 struct btrfs_fs_info;
425 
426 int repair_io_failure(struct inode *inode, u64 start, u64 length, u64 logical,
427 		      struct page *page, unsigned int pg_offset,
428 		      int mirror_num);
429 int clean_io_failure(struct inode *inode, u64 start, struct page *page,
430 		     unsigned int pg_offset);
431 void end_extent_writepage(struct page *page, int err, u64 start, u64 end);
432 int repair_eb_io_failure(struct btrfs_root *root, struct extent_buffer *eb,
433 			 int mirror_num);
434 
435 /*
436  * When IO fails, either with EIO or csum verification fails, we
437  * try other mirrors that might have a good copy of the data.  This
438  * io_failure_record is used to record state as we go through all the
439  * mirrors.  If another mirror has good data, the page is set up to date
440  * and things continue.  If a good mirror can't be found, the original
441  * bio end_io callback is called to indicate things have failed.
442  */
443 struct io_failure_record {
444 	struct page *page;
445 	u64 start;
446 	u64 len;
447 	u64 logical;
448 	unsigned long bio_flags;
449 	int this_mirror;
450 	int failed_mirror;
451 	int in_validation;
452 };
453 
454 void btrfs_free_io_failure_record(struct inode *inode, u64 start, u64 end);
455 int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
456 				struct io_failure_record **failrec_ret);
457 int btrfs_check_repairable(struct inode *inode, struct bio *failed_bio,
458 			   struct io_failure_record *failrec, int fail_mirror);
459 struct bio *btrfs_create_repair_bio(struct inode *inode, struct bio *failed_bio,
460 				    struct io_failure_record *failrec,
461 				    struct page *page, int pg_offset, int icsum,
462 				    bio_end_io_t *endio_func, void *data);
463 int free_io_failure(struct inode *inode, struct io_failure_record *rec);
464 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
465 noinline u64 find_lock_delalloc_range(struct inode *inode,
466 				      struct extent_io_tree *tree,
467 				      struct page *locked_page, u64 *start,
468 				      u64 *end, u64 max_bytes);
469 #endif
470 struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
471 					       u64 start);
472 #endif
473