xref: /linux/fs/btrfs/volumes.h (revision b8321ed4a40c02054f930ca59d3570caa27bc86c)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 2007 Oracle.  All rights reserved.
4  */
5 
6 #ifndef BTRFS_VOLUMES_H
7 #define BTRFS_VOLUMES_H
8 
9 #include <linux/bio.h>
10 #include <linux/sort.h>
11 #include <linux/btrfs.h>
12 #include "async-thread.h"
13 
14 #define BTRFS_MAX_DATA_CHUNK_SIZE	(10ULL * SZ_1G)
15 
16 extern struct mutex uuid_mutex;
17 
18 #define BTRFS_STRIPE_LEN	SZ_64K
19 
20 struct btrfs_io_geometry {
21 	/* remaining bytes before crossing a stripe */
22 	u64 len;
23 	/* offset of logical address in chunk */
24 	u64 offset;
25 	/* length of single IO stripe */
26 	u64 stripe_len;
27 	/* number of stripe where address falls */
28 	u64 stripe_nr;
29 	/* offset of address in stripe */
30 	u64 stripe_offset;
31 	/* offset of raid56 stripe into the chunk */
32 	u64 raid56_stripe_offset;
33 };
34 
35 /*
36  * Use sequence counter to get consistent device stat data on
37  * 32-bit processors.
38  */
39 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
40 #include <linux/seqlock.h>
41 #define __BTRFS_NEED_DEVICE_DATA_ORDERED
42 #define btrfs_device_data_ordered_init(device)	\
43 	seqcount_init(&device->data_seqcount)
44 #else
45 #define btrfs_device_data_ordered_init(device) do { } while (0)
46 #endif
47 
48 #define BTRFS_DEV_STATE_WRITEABLE	(0)
49 #define BTRFS_DEV_STATE_IN_FS_METADATA	(1)
50 #define BTRFS_DEV_STATE_MISSING		(2)
51 #define BTRFS_DEV_STATE_REPLACE_TGT	(3)
52 #define BTRFS_DEV_STATE_FLUSH_SENT	(4)
53 #define BTRFS_DEV_STATE_NO_READA	(5)
54 
55 struct btrfs_zoned_device_info;
56 
57 struct btrfs_device {
58 	struct list_head dev_list; /* device_list_mutex */
59 	struct list_head dev_alloc_list; /* chunk mutex */
60 	struct list_head post_commit_list; /* chunk mutex */
61 	struct btrfs_fs_devices *fs_devices;
62 	struct btrfs_fs_info *fs_info;
63 
64 	struct rcu_string __rcu *name;
65 
66 	u64 generation;
67 
68 	struct block_device *bdev;
69 
70 	struct btrfs_zoned_device_info *zone_info;
71 
72 	/* the mode sent to blkdev_get */
73 	fmode_t mode;
74 
75 	/*
76 	 * Device's major-minor number. Must be set even if the device is not
77 	 * opened (bdev == NULL), unless the device is missing.
78 	 */
79 	dev_t devt;
80 	unsigned long dev_state;
81 	blk_status_t last_flush_error;
82 
83 #ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
84 	seqcount_t data_seqcount;
85 #endif
86 
87 	/* the internal btrfs device id */
88 	u64 devid;
89 
90 	/* size of the device in memory */
91 	u64 total_bytes;
92 
93 	/* size of the device on disk */
94 	u64 disk_total_bytes;
95 
96 	/* bytes used */
97 	u64 bytes_used;
98 
99 	/* optimal io alignment for this device */
100 	u32 io_align;
101 
102 	/* optimal io width for this device */
103 	u32 io_width;
104 	/* type and info about this device */
105 	u64 type;
106 
107 	/* minimal io size for this device */
108 	u32 sector_size;
109 
110 	/* physical drive uuid (or lvm uuid) */
111 	u8 uuid[BTRFS_UUID_SIZE];
112 
113 	/*
114 	 * size of the device on the current transaction
115 	 *
116 	 * This variant is update when committing the transaction,
117 	 * and protected by chunk mutex
118 	 */
119 	u64 commit_total_bytes;
120 
121 	/* bytes used on the current transaction */
122 	u64 commit_bytes_used;
123 
124 	/* for sending down flush barriers */
125 	struct bio *flush_bio;
126 	struct completion flush_wait;
127 
128 	/* per-device scrub information */
129 	struct scrub_ctx *scrub_ctx;
130 
131 	/* disk I/O failure stats. For detailed description refer to
132 	 * enum btrfs_dev_stat_values in ioctl.h */
133 	int dev_stats_valid;
134 
135 	/* Counter to record the change of device stats */
136 	atomic_t dev_stats_ccnt;
137 	atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
138 
139 	struct extent_io_tree alloc_state;
140 
141 	struct completion kobj_unregister;
142 	/* For sysfs/FSID/devinfo/devid/ */
143 	struct kobject devid_kobj;
144 
145 	/* Bandwidth limit for scrub, in bytes */
146 	u64 scrub_speed_max;
147 };
148 
149 /*
150  * If we read those variants at the context of their own lock, we needn't
151  * use the following helpers, reading them directly is safe.
152  */
153 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
154 #define BTRFS_DEVICE_GETSET_FUNCS(name)					\
155 static inline u64							\
156 btrfs_device_get_##name(const struct btrfs_device *dev)			\
157 {									\
158 	u64 size;							\
159 	unsigned int seq;						\
160 									\
161 	do {								\
162 		seq = read_seqcount_begin(&dev->data_seqcount);		\
163 		size = dev->name;					\
164 	} while (read_seqcount_retry(&dev->data_seqcount, seq));	\
165 	return size;							\
166 }									\
167 									\
168 static inline void							\
169 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
170 {									\
171 	preempt_disable();						\
172 	write_seqcount_begin(&dev->data_seqcount);			\
173 	dev->name = size;						\
174 	write_seqcount_end(&dev->data_seqcount);			\
175 	preempt_enable();						\
176 }
177 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
178 #define BTRFS_DEVICE_GETSET_FUNCS(name)					\
179 static inline u64							\
180 btrfs_device_get_##name(const struct btrfs_device *dev)			\
181 {									\
182 	u64 size;							\
183 									\
184 	preempt_disable();						\
185 	size = dev->name;						\
186 	preempt_enable();						\
187 	return size;							\
188 }									\
189 									\
190 static inline void							\
191 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
192 {									\
193 	preempt_disable();						\
194 	dev->name = size;						\
195 	preempt_enable();						\
196 }
197 #else
198 #define BTRFS_DEVICE_GETSET_FUNCS(name)					\
199 static inline u64							\
200 btrfs_device_get_##name(const struct btrfs_device *dev)			\
201 {									\
202 	return dev->name;						\
203 }									\
204 									\
205 static inline void							\
206 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
207 {									\
208 	dev->name = size;						\
209 }
210 #endif
211 
212 BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
213 BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
214 BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
215 
216 enum btrfs_chunk_allocation_policy {
217 	BTRFS_CHUNK_ALLOC_REGULAR,
218 	BTRFS_CHUNK_ALLOC_ZONED,
219 };
220 
221 /*
222  * Read policies for mirrored block group profiles, read picks the stripe based
223  * on these policies.
224  */
225 enum btrfs_read_policy {
226 	/* Use process PID to choose the stripe */
227 	BTRFS_READ_POLICY_PID,
228 	BTRFS_NR_READ_POLICY,
229 };
230 
231 struct btrfs_fs_devices {
232 	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
233 	u8 metadata_uuid[BTRFS_FSID_SIZE];
234 	bool fsid_change;
235 	struct list_head fs_list;
236 
237 	/*
238 	 * Number of devices under this fsid including missing and
239 	 * replace-target device and excludes seed devices.
240 	 */
241 	u64 num_devices;
242 
243 	/*
244 	 * The number of devices that successfully opened, including
245 	 * replace-target, excludes seed devices.
246 	 */
247 	u64 open_devices;
248 
249 	/* The number of devices that are under the chunk allocation list. */
250 	u64 rw_devices;
251 
252 	/* Count of missing devices under this fsid excluding seed device. */
253 	u64 missing_devices;
254 	u64 total_rw_bytes;
255 
256 	/*
257 	 * Count of devices from btrfs_super_block::num_devices for this fsid,
258 	 * which includes the seed device, excludes the transient replace-target
259 	 * device.
260 	 */
261 	u64 total_devices;
262 
263 	/* Highest generation number of seen devices */
264 	u64 latest_generation;
265 
266 	/*
267 	 * The mount device or a device with highest generation after removal
268 	 * or replace.
269 	 */
270 	struct btrfs_device *latest_dev;
271 
272 	/* all of the devices in the FS, protected by a mutex
273 	 * so we can safely walk it to write out the supers without
274 	 * worrying about add/remove by the multi-device code.
275 	 * Scrubbing super can kick off supers writing by holding
276 	 * this mutex lock.
277 	 */
278 	struct mutex device_list_mutex;
279 
280 	/* List of all devices, protected by device_list_mutex */
281 	struct list_head devices;
282 
283 	/*
284 	 * Devices which can satisfy space allocation. Protected by
285 	 * chunk_mutex
286 	 */
287 	struct list_head alloc_list;
288 
289 	struct list_head seed_list;
290 	bool seeding;
291 
292 	int opened;
293 
294 	/* set when we find or add a device that doesn't have the
295 	 * nonrot flag set
296 	 */
297 	bool rotating;
298 
299 	struct btrfs_fs_info *fs_info;
300 	/* sysfs kobjects */
301 	struct kobject fsid_kobj;
302 	struct kobject *devices_kobj;
303 	struct kobject *devinfo_kobj;
304 	struct completion kobj_unregister;
305 
306 	enum btrfs_chunk_allocation_policy chunk_alloc_policy;
307 
308 	/* Policy used to read the mirrored stripes */
309 	enum btrfs_read_policy read_policy;
310 };
311 
312 #define BTRFS_BIO_INLINE_CSUM_SIZE	64
313 
314 #define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info)	\
315 			- sizeof(struct btrfs_chunk))		\
316 			/ sizeof(struct btrfs_stripe) + 1)
317 
318 #define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE	\
319 				- 2 * sizeof(struct btrfs_disk_key)	\
320 				- 2 * sizeof(struct btrfs_chunk))	\
321 				/ sizeof(struct btrfs_stripe) + 1)
322 
323 /*
324  * Additional info to pass along bio.
325  *
326  * Mostly for btrfs specific features like csum and mirror_num.
327  */
328 struct btrfs_bio {
329 	unsigned int mirror_num;
330 
331 	/* @device is for stripe IO submission. */
332 	struct btrfs_device *device;
333 	u8 *csum;
334 	u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
335 	struct bvec_iter iter;
336 
337 	/*
338 	 * This member must come last, bio_alloc_bioset will allocate enough
339 	 * bytes for entire btrfs_bio but relies on bio being last.
340 	 */
341 	struct bio bio;
342 };
343 
344 static inline struct btrfs_bio *btrfs_bio(struct bio *bio)
345 {
346 	return container_of(bio, struct btrfs_bio, bio);
347 }
348 
349 static inline void btrfs_bio_free_csum(struct btrfs_bio *bbio)
350 {
351 	if (bbio->csum != bbio->csum_inline) {
352 		kfree(bbio->csum);
353 		bbio->csum = NULL;
354 	}
355 }
356 
357 struct btrfs_io_stripe {
358 	struct btrfs_device *dev;
359 	u64 physical;
360 	u64 length; /* only used for discard mappings */
361 };
362 
363 /*
364  * Context for IO subsmission for device stripe.
365  *
366  * - Track the unfinished mirrors for mirror based profiles
367  *   Mirror based profiles are SINGLE/DUP/RAID1/RAID10.
368  *
369  * - Contain the logical -> physical mapping info
370  *   Used by submit_stripe_bio() for mapping logical bio
371  *   into physical device address.
372  *
373  * - Contain device replace info
374  *   Used by handle_ops_on_dev_replace() to copy logical bios
375  *   into the new device.
376  *
377  * - Contain RAID56 full stripe logical bytenrs
378  */
379 struct btrfs_io_context {
380 	refcount_t refs;
381 	atomic_t stripes_pending;
382 	struct btrfs_fs_info *fs_info;
383 	u64 map_type; /* get from map_lookup->type */
384 	bio_end_io_t *end_io;
385 	struct bio *orig_bio;
386 	void *private;
387 	atomic_t error;
388 	int max_errors;
389 	int num_stripes;
390 	int mirror_num;
391 	int num_tgtdevs;
392 	int *tgtdev_map;
393 	/*
394 	 * logical block numbers for the start of each stripe
395 	 * The last one or two are p/q.  These are sorted,
396 	 * so raid_map[0] is the start of our full stripe
397 	 */
398 	u64 *raid_map;
399 	struct btrfs_io_stripe stripes[];
400 };
401 
402 struct btrfs_device_info {
403 	struct btrfs_device *dev;
404 	u64 dev_offset;
405 	u64 max_avail;
406 	u64 total_avail;
407 };
408 
409 struct btrfs_raid_attr {
410 	u8 sub_stripes;		/* sub_stripes info for map */
411 	u8 dev_stripes;		/* stripes per dev */
412 	u8 devs_max;		/* max devs to use */
413 	u8 devs_min;		/* min devs needed */
414 	u8 tolerated_failures;	/* max tolerated fail devs */
415 	u8 devs_increment;	/* ndevs has to be a multiple of this */
416 	u8 ncopies;		/* how many copies to data has */
417 	u8 nparity;		/* number of stripes worth of bytes to store
418 				 * parity information */
419 	u8 mindev_error;	/* error code if min devs requisite is unmet */
420 	const char raid_name[8]; /* name of the raid */
421 	u64 bg_flag;		/* block group flag of the raid */
422 };
423 
424 extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
425 
426 struct map_lookup {
427 	u64 type;
428 	int io_align;
429 	int io_width;
430 	u64 stripe_len;
431 	int num_stripes;
432 	int sub_stripes;
433 	int verified_stripes; /* For mount time dev extent verification */
434 	struct btrfs_io_stripe stripes[];
435 };
436 
437 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
438 			    (sizeof(struct btrfs_io_stripe) * (n)))
439 
440 struct btrfs_balance_args;
441 struct btrfs_balance_progress;
442 struct btrfs_balance_control {
443 	struct btrfs_balance_args data;
444 	struct btrfs_balance_args meta;
445 	struct btrfs_balance_args sys;
446 
447 	u64 flags;
448 
449 	struct btrfs_balance_progress stat;
450 };
451 
452 /*
453  * Search for a given device by the set parameters
454  */
455 struct btrfs_dev_lookup_args {
456 	u64 devid;
457 	u8 *uuid;
458 	u8 *fsid;
459 	bool missing;
460 };
461 
462 /* We have to initialize to -1 because BTRFS_DEV_REPLACE_DEVID is 0 */
463 #define BTRFS_DEV_LOOKUP_ARGS_INIT { .devid = (u64)-1 }
464 
465 #define BTRFS_DEV_LOOKUP_ARGS(name) \
466 	struct btrfs_dev_lookup_args name = BTRFS_DEV_LOOKUP_ARGS_INIT
467 
468 enum btrfs_map_op {
469 	BTRFS_MAP_READ,
470 	BTRFS_MAP_WRITE,
471 	BTRFS_MAP_DISCARD,
472 	BTRFS_MAP_GET_READ_MIRRORS,
473 };
474 
475 static inline enum btrfs_map_op btrfs_op(struct bio *bio)
476 {
477 	switch (bio_op(bio)) {
478 	case REQ_OP_DISCARD:
479 		return BTRFS_MAP_DISCARD;
480 	case REQ_OP_WRITE:
481 	case REQ_OP_ZONE_APPEND:
482 		return BTRFS_MAP_WRITE;
483 	default:
484 		WARN_ON_ONCE(1);
485 		fallthrough;
486 	case REQ_OP_READ:
487 		return BTRFS_MAP_READ;
488 	}
489 }
490 
491 void btrfs_get_bioc(struct btrfs_io_context *bioc);
492 void btrfs_put_bioc(struct btrfs_io_context *bioc);
493 int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
494 		    u64 logical, u64 *length,
495 		    struct btrfs_io_context **bioc_ret, int mirror_num);
496 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
497 		     u64 logical, u64 *length,
498 		     struct btrfs_io_context **bioc_ret);
499 int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, struct extent_map *map,
500 			  enum btrfs_map_op op, u64 logical,
501 			  struct btrfs_io_geometry *io_geom);
502 int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
503 int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
504 struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans,
505 					    u64 type);
506 void btrfs_mapping_tree_free(struct extent_map_tree *tree);
507 blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
508 			   int mirror_num);
509 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
510 		       fmode_t flags, void *holder);
511 struct btrfs_device *btrfs_scan_one_device(const char *path,
512 					   fmode_t flags, void *holder);
513 int btrfs_forget_devices(dev_t devt);
514 void btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
515 void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices);
516 void btrfs_assign_next_active_device(struct btrfs_device *device,
517 				     struct btrfs_device *this_dev);
518 struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
519 						  u64 devid,
520 						  const char *devpath);
521 int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
522 				 struct btrfs_dev_lookup_args *args,
523 				 const char *path);
524 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
525 					const u64 *devid,
526 					const u8 *uuid);
527 void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args);
528 void btrfs_free_device(struct btrfs_device *device);
529 int btrfs_rm_device(struct btrfs_fs_info *fs_info,
530 		    struct btrfs_dev_lookup_args *args,
531 		    struct block_device **bdev, fmode_t *mode);
532 void __exit btrfs_cleanup_fs_uuids(void);
533 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
534 int btrfs_grow_device(struct btrfs_trans_handle *trans,
535 		      struct btrfs_device *device, u64 new_size);
536 struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices,
537 				       const struct btrfs_dev_lookup_args *args);
538 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
539 int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
540 int btrfs_balance(struct btrfs_fs_info *fs_info,
541 		  struct btrfs_balance_control *bctl,
542 		  struct btrfs_ioctl_balance_args *bargs);
543 void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
544 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
545 int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
546 int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
547 int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset);
548 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
549 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
550 int btrfs_uuid_scan_kthread(void *data);
551 bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset);
552 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
553 			 u64 *start, u64 *max_avail);
554 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
555 int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
556 			struct btrfs_ioctl_get_dev_stats *stats);
557 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
558 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
559 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans);
560 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);
561 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);
562 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);
563 int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
564 			   u64 logical, u64 len);
565 unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
566 				    u64 logical);
567 int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans,
568 				     struct btrfs_block_group *bg);
569 int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);
570 struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
571 				       u64 logical, u64 length);
572 void btrfs_release_disk_super(struct btrfs_super_block *super);
573 
574 static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
575 				      int index)
576 {
577 	atomic_inc(dev->dev_stat_values + index);
578 	/*
579 	 * This memory barrier orders stores updating statistics before stores
580 	 * updating dev_stats_ccnt.
581 	 *
582 	 * It pairs with smp_rmb() in btrfs_run_dev_stats().
583 	 */
584 	smp_mb__before_atomic();
585 	atomic_inc(&dev->dev_stats_ccnt);
586 }
587 
588 static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
589 				      int index)
590 {
591 	return atomic_read(dev->dev_stat_values + index);
592 }
593 
594 static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
595 						int index)
596 {
597 	int ret;
598 
599 	ret = atomic_xchg(dev->dev_stat_values + index, 0);
600 	/*
601 	 * atomic_xchg implies a full memory barriers as per atomic_t.txt:
602 	 * - RMW operations that have a return value are fully ordered;
603 	 *
604 	 * This implicit memory barriers is paired with the smp_rmb in
605 	 * btrfs_run_dev_stats
606 	 */
607 	atomic_inc(&dev->dev_stats_ccnt);
608 	return ret;
609 }
610 
611 static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
612 				      int index, unsigned long val)
613 {
614 	atomic_set(dev->dev_stat_values + index, val);
615 	/*
616 	 * This memory barrier orders stores updating statistics before stores
617 	 * updating dev_stats_ccnt.
618 	 *
619 	 * It pairs with smp_rmb() in btrfs_run_dev_stats().
620 	 */
621 	smp_mb__before_atomic();
622 	atomic_inc(&dev->dev_stats_ccnt);
623 }
624 
625 void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
626 
627 struct list_head * __attribute_const__ btrfs_get_fs_uuids(void);
628 bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
629 					struct btrfs_device *failing_dev);
630 void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info,
631 			       struct block_device *bdev,
632 			       const char *device_path);
633 
634 enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags);
635 int btrfs_bg_type_to_factor(u64 flags);
636 const char *btrfs_bg_type_to_raid_name(u64 flags);
637 int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
638 bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical);
639 
640 #endif
641