xref: /openbmc/linux/fs/btrfs/extent_io.h (revision 7bcae826)
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_CLEAR_DATA_RESV	(1U << 17)
24 #define EXTENT_IOBITS		(EXTENT_LOCKED | EXTENT_WRITEBACK)
25 #define EXTENT_CTLBITS		(EXTENT_DO_ACCOUNTING | EXTENT_FIRST_DELALLOC)
26 
27 /*
28  * flags for bio submission. The high bits indicate the compression
29  * type for this bio
30  */
31 #define EXTENT_BIO_COMPRESSED 1
32 #define EXTENT_BIO_TREE_LOG 2
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 __process_pages_contig */
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 #define PAGE_LOCK		(1 << 6)
56 
57 /*
58  * page->private values.  Every page that is controlled by the extent
59  * map has page->private set to one.
60  */
61 #define EXTENT_PAGE_PRIVATE 1
62 
63 /*
64  * The extent buffer bitmap operations are done with byte granularity instead of
65  * word granularity for two reasons:
66  * 1. The bitmaps must be little-endian on disk.
67  * 2. Bitmap items are not guaranteed to be aligned to a word and therefore a
68  *    single word in a bitmap may straddle two pages in the extent buffer.
69  */
70 #define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE)
71 #define BYTE_MASK ((1 << BITS_PER_BYTE) - 1)
72 #define BITMAP_FIRST_BYTE_MASK(start) \
73 	((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK)
74 #define BITMAP_LAST_BYTE_MASK(nbits) \
75 	(BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1)))
76 
77 static inline int le_test_bit(int nr, const u8 *addr)
78 {
79 	return 1U & (addr[BIT_BYTE(nr)] >> (nr & (BITS_PER_BYTE-1)));
80 }
81 
82 extern void le_bitmap_set(u8 *map, unsigned int start, int len);
83 extern void le_bitmap_clear(u8 *map, unsigned int start, int len);
84 
85 struct extent_state;
86 struct btrfs_root;
87 struct btrfs_io_bio;
88 struct io_failure_record;
89 
90 typedef	int (extent_submit_bio_hook_t)(struct inode *inode, struct bio *bio,
91 				       int mirror_num, unsigned long bio_flags,
92 				       u64 bio_offset);
93 struct extent_io_ops {
94 	int (*fill_delalloc)(struct inode *inode, struct page *locked_page,
95 			     u64 start, u64 end, int *page_started,
96 			     unsigned long *nr_written);
97 	int (*writepage_start_hook)(struct page *page, u64 start, u64 end);
98 	extent_submit_bio_hook_t *submit_bio_hook;
99 	int (*merge_bio_hook)(struct page *page, unsigned long offset,
100 			      size_t size, struct bio *bio,
101 			      unsigned long bio_flags);
102 	int (*readpage_io_failed_hook)(struct page *page, int failed_mirror);
103 	int (*readpage_end_io_hook)(struct btrfs_io_bio *io_bio, u64 phy_offset,
104 				    struct page *page, u64 start, u64 end,
105 				    int mirror);
106 	int (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
107 				      struct extent_state *state, int uptodate);
108 	void (*set_bit_hook)(struct inode *inode, struct extent_state *state,
109 			     unsigned *bits);
110 	void (*clear_bit_hook)(struct inode *inode, struct extent_state *state,
111 			       unsigned *bits);
112 	void (*merge_extent_hook)(struct inode *inode,
113 				  struct extent_state *new,
114 				  struct extent_state *other);
115 	void (*split_extent_hook)(struct inode *inode,
116 				  struct extent_state *orig, u64 split);
117 };
118 
119 struct extent_io_tree {
120 	struct rb_root state;
121 	struct address_space *mapping;
122 	u64 dirty_bytes;
123 	int track_uptodate;
124 	spinlock_t lock;
125 	const struct extent_io_ops *ops;
126 };
127 
128 struct extent_state {
129 	u64 start;
130 	u64 end; /* inclusive */
131 	struct rb_node rb_node;
132 
133 	/* ADD NEW ELEMENTS AFTER THIS */
134 	wait_queue_head_t wq;
135 	atomic_t refs;
136 	unsigned state;
137 
138 	struct io_failure_record *failrec;
139 
140 #ifdef CONFIG_BTRFS_DEBUG
141 	struct list_head leak_list;
142 #endif
143 };
144 
145 #define INLINE_EXTENT_BUFFER_PAGES 16
146 #define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_SIZE)
147 struct extent_buffer {
148 	u64 start;
149 	unsigned long len;
150 	unsigned long bflags;
151 	struct btrfs_fs_info *fs_info;
152 	spinlock_t refs_lock;
153 	atomic_t refs;
154 	atomic_t io_pages;
155 	int read_mirror;
156 	struct rcu_head rcu_head;
157 	pid_t lock_owner;
158 
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 
170 	/* protects write locks */
171 	rwlock_t lock;
172 
173 	/* readers use lock_wq while they wait for the write
174 	 * lock holders to unlock
175 	 */
176 	wait_queue_head_t write_lock_wq;
177 
178 	/* writers use read_lock_wq while they wait for readers
179 	 * to unlock
180 	 */
181 	wait_queue_head_t read_lock_wq;
182 	struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
183 #ifdef CONFIG_BTRFS_DEBUG
184 	struct list_head leak_list;
185 #endif
186 };
187 
188 /*
189  * Structure to record how many bytes and which ranges are set/cleared
190  */
191 struct extent_changeset {
192 	/* How many bytes are set/cleared in this operation */
193 	u64 bytes_changed;
194 
195 	/* Changed ranges */
196 	struct ulist range_changed;
197 };
198 
199 static inline void extent_set_compress_type(unsigned long *bio_flags,
200 					    int compress_type)
201 {
202 	*bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT;
203 }
204 
205 static inline int extent_compress_type(unsigned long bio_flags)
206 {
207 	return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
208 }
209 
210 struct extent_map_tree;
211 
212 typedef struct extent_map *(get_extent_t)(struct inode *inode,
213 					  struct page *page,
214 					  size_t pg_offset,
215 					  u64 start, u64 len,
216 					  int create);
217 
218 void extent_io_tree_init(struct extent_io_tree *tree,
219 			 struct address_space *mapping);
220 int try_release_extent_mapping(struct extent_map_tree *map,
221 			       struct extent_io_tree *tree, struct page *page,
222 			       gfp_t mask);
223 int try_release_extent_buffer(struct page *page);
224 int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
225 		     struct extent_state **cached);
226 
227 static inline int lock_extent(struct extent_io_tree *tree, u64 start, u64 end)
228 {
229 	return lock_extent_bits(tree, start, end, NULL);
230 }
231 
232 int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
233 int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
234 			  get_extent_t *get_extent, int mirror_num);
235 int __init extent_io_init(void);
236 void extent_io_exit(void);
237 
238 u64 count_range_bits(struct extent_io_tree *tree,
239 		     u64 *start, u64 search_end,
240 		     u64 max_bytes, unsigned bits, int contig);
241 
242 void free_extent_state(struct extent_state *state);
243 int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
244 		   unsigned bits, int filled,
245 		   struct extent_state *cached_state);
246 int clear_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
247 		unsigned bits, struct extent_changeset *changeset);
248 int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
249 		     unsigned bits, int wake, int delete,
250 		     struct extent_state **cached, gfp_t mask);
251 
252 static inline int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end)
253 {
254 	return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL,
255 				GFP_NOFS);
256 }
257 
258 static inline int unlock_extent_cached(struct extent_io_tree *tree, u64 start,
259 		u64 end, struct extent_state **cached, gfp_t mask)
260 {
261 	return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
262 				mask);
263 }
264 
265 static inline int clear_extent_bits(struct extent_io_tree *tree, u64 start,
266 		u64 end, unsigned bits)
267 {
268 	int wake = 0;
269 
270 	if (bits & EXTENT_LOCKED)
271 		wake = 1;
272 
273 	return clear_extent_bit(tree, start, end, bits, wake, 0, NULL,
274 			GFP_NOFS);
275 }
276 
277 int set_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
278 			   unsigned bits, struct extent_changeset *changeset);
279 int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
280 		   unsigned bits, u64 *failed_start,
281 		   struct extent_state **cached_state, gfp_t mask);
282 
283 static inline int set_extent_bits(struct extent_io_tree *tree, u64 start,
284 		u64 end, unsigned bits)
285 {
286 	return set_extent_bit(tree, start, end, bits, NULL, NULL, GFP_NOFS);
287 }
288 
289 static inline int clear_extent_uptodate(struct extent_io_tree *tree, u64 start,
290 		u64 end, struct extent_state **cached_state, gfp_t mask)
291 {
292 	return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0,
293 				cached_state, mask);
294 }
295 
296 static inline int set_extent_dirty(struct extent_io_tree *tree, u64 start,
297 		u64 end, gfp_t mask)
298 {
299 	return set_extent_bit(tree, start, end, EXTENT_DIRTY, NULL,
300 			      NULL, mask);
301 }
302 
303 static inline int clear_extent_dirty(struct extent_io_tree *tree, u64 start,
304 		u64 end)
305 {
306 	return clear_extent_bit(tree, start, end,
307 				EXTENT_DIRTY | EXTENT_DELALLOC |
308 				EXTENT_DO_ACCOUNTING, 0, 0, NULL, GFP_NOFS);
309 }
310 
311 int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
312 		       unsigned bits, unsigned clear_bits,
313 		       struct extent_state **cached_state);
314 
315 static inline int set_extent_delalloc(struct extent_io_tree *tree, u64 start,
316 		u64 end, struct extent_state **cached_state)
317 {
318 	return set_extent_bit(tree, start, end,
319 			      EXTENT_DELALLOC | EXTENT_UPTODATE,
320 			      NULL, cached_state, GFP_NOFS);
321 }
322 
323 static inline int set_extent_defrag(struct extent_io_tree *tree, u64 start,
324 		u64 end, struct extent_state **cached_state)
325 {
326 	return set_extent_bit(tree, start, end,
327 			      EXTENT_DELALLOC | EXTENT_UPTODATE | EXTENT_DEFRAG,
328 			      NULL, cached_state, GFP_NOFS);
329 }
330 
331 static inline int set_extent_new(struct extent_io_tree *tree, u64 start,
332 		u64 end)
333 {
334 	return set_extent_bit(tree, start, end, EXTENT_NEW, NULL, NULL,
335 			GFP_NOFS);
336 }
337 
338 static inline int set_extent_uptodate(struct extent_io_tree *tree, u64 start,
339 		u64 end, struct extent_state **cached_state, gfp_t mask)
340 {
341 	return set_extent_bit(tree, start, end, EXTENT_UPTODATE, NULL,
342 			      cached_state, mask);
343 }
344 
345 int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
346 			  u64 *start_ret, u64 *end_ret, unsigned bits,
347 			  struct extent_state **cached_state);
348 int extent_invalidatepage(struct extent_io_tree *tree,
349 			  struct page *page, unsigned long offset);
350 int extent_write_full_page(struct extent_io_tree *tree, struct page *page,
351 			  get_extent_t *get_extent,
352 			  struct writeback_control *wbc);
353 int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode,
354 			      u64 start, u64 end, get_extent_t *get_extent,
355 			      int mode);
356 int extent_writepages(struct extent_io_tree *tree,
357 		      struct address_space *mapping,
358 		      get_extent_t *get_extent,
359 		      struct writeback_control *wbc);
360 int btree_write_cache_pages(struct address_space *mapping,
361 			    struct writeback_control *wbc);
362 int extent_readpages(struct extent_io_tree *tree,
363 		     struct address_space *mapping,
364 		     struct list_head *pages, unsigned nr_pages,
365 		     get_extent_t get_extent);
366 int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
367 		__u64 start, __u64 len, get_extent_t *get_extent);
368 void set_page_extent_mapped(struct page *page);
369 
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 			     get_extent_t *get_extent, int mirror_num);
387 void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
388 
389 static inline unsigned long num_extent_pages(u64 start, u64 len)
390 {
391 	return ((start + len + PAGE_SIZE - 1) >> PAGE_SHIFT) -
392 		(start >> PAGE_SHIFT);
393 }
394 
395 static inline void extent_buffer_get(struct extent_buffer *eb)
396 {
397 	atomic_inc(&eb->refs);
398 }
399 
400 int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
401 			  unsigned long start,
402 			  unsigned long len);
403 void read_extent_buffer(struct extent_buffer *eb, void *dst,
404 			unsigned long start,
405 			unsigned long len);
406 int read_extent_buffer_to_user(struct extent_buffer *eb, void __user *dst,
407 			       unsigned long start,
408 			       unsigned long len);
409 void write_extent_buffer_fsid(struct extent_buffer *eb, const void *src);
410 void write_extent_buffer_chunk_tree_uuid(struct extent_buffer *eb,
411 		const void *src);
412 void write_extent_buffer(struct extent_buffer *eb, const void *src,
413 			 unsigned long start, unsigned long len);
414 void copy_extent_buffer_full(struct extent_buffer *dst,
415 			     struct extent_buffer *src);
416 void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
417 			unsigned long dst_offset, unsigned long src_offset,
418 			unsigned long len);
419 void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
420 			   unsigned long src_offset, unsigned long len);
421 void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
422 			   unsigned long src_offset, unsigned long len);
423 void memzero_extent_buffer(struct extent_buffer *eb, unsigned long start,
424 			   unsigned long len);
425 int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start,
426 			   unsigned long pos);
427 void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start,
428 			      unsigned long pos, unsigned long len);
429 void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start,
430 				unsigned long pos, unsigned long len);
431 void clear_extent_buffer_dirty(struct extent_buffer *eb);
432 int set_extent_buffer_dirty(struct extent_buffer *eb);
433 void set_extent_buffer_uptodate(struct extent_buffer *eb);
434 void clear_extent_buffer_uptodate(struct extent_buffer *eb);
435 int extent_buffer_uptodate(struct extent_buffer *eb);
436 int extent_buffer_under_io(struct extent_buffer *eb);
437 int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
438 		      unsigned long min_len, char **map,
439 		      unsigned long *map_start,
440 		      unsigned long *map_len);
441 void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
442 void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
443 void extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end,
444 				 u64 delalloc_end, struct page *locked_page,
445 				 unsigned bits_to_clear,
446 				 unsigned long page_ops);
447 struct bio *
448 btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
449 		gfp_t gfp_flags);
450 struct bio *btrfs_io_bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs);
451 struct bio *btrfs_bio_clone(struct bio *bio, gfp_t gfp_mask);
452 
453 struct btrfs_fs_info;
454 
455 int repair_io_failure(struct inode *inode, u64 start, u64 length, u64 logical,
456 		      struct page *page, unsigned int pg_offset,
457 		      int mirror_num);
458 int clean_io_failure(struct inode *inode, u64 start, struct page *page,
459 		     unsigned int pg_offset);
460 void end_extent_writepage(struct page *page, int err, u64 start, u64 end);
461 int repair_eb_io_failure(struct btrfs_fs_info *fs_info,
462 			 struct extent_buffer *eb, int mirror_num);
463 
464 /*
465  * When IO fails, either with EIO or csum verification fails, we
466  * try other mirrors that might have a good copy of the data.  This
467  * io_failure_record is used to record state as we go through all the
468  * mirrors.  If another mirror has good data, the page is set up to date
469  * and things continue.  If a good mirror can't be found, the original
470  * bio end_io callback is called to indicate things have failed.
471  */
472 struct io_failure_record {
473 	struct page *page;
474 	u64 start;
475 	u64 len;
476 	u64 logical;
477 	unsigned long bio_flags;
478 	int this_mirror;
479 	int failed_mirror;
480 	int in_validation;
481 };
482 
483 void btrfs_free_io_failure_record(struct inode *inode, u64 start, u64 end);
484 int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
485 				struct io_failure_record **failrec_ret);
486 int btrfs_check_repairable(struct inode *inode, struct bio *failed_bio,
487 			   struct io_failure_record *failrec, int fail_mirror);
488 struct bio *btrfs_create_repair_bio(struct inode *inode, struct bio *failed_bio,
489 				    struct io_failure_record *failrec,
490 				    struct page *page, int pg_offset, int icsum,
491 				    bio_end_io_t *endio_func, void *data);
492 int free_io_failure(struct inode *inode, struct io_failure_record *rec);
493 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
494 noinline u64 find_lock_delalloc_range(struct inode *inode,
495 				      struct extent_io_tree *tree,
496 				      struct page *locked_page, u64 *start,
497 				      u64 *end, u64 max_bytes);
498 #endif
499 struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
500 					       u64 start);
501 #endif
502