xref: /linux/fs/btrfs/volumes.h (revision aec499c75cf8e0b599be4d559e6922b613085f8f)
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 	unsigned long dev_state;
76 	blk_status_t last_flush_error;
77 
78 #ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
79 	seqcount_t data_seqcount;
80 #endif
81 
82 	/* the internal btrfs device id */
83 	u64 devid;
84 
85 	/* size of the device in memory */
86 	u64 total_bytes;
87 
88 	/* size of the device on disk */
89 	u64 disk_total_bytes;
90 
91 	/* bytes used */
92 	u64 bytes_used;
93 
94 	/* optimal io alignment for this device */
95 	u32 io_align;
96 
97 	/* optimal io width for this device */
98 	u32 io_width;
99 	/* type and info about this device */
100 	u64 type;
101 
102 	/* minimal io size for this device */
103 	u32 sector_size;
104 
105 	/* physical drive uuid (or lvm uuid) */
106 	u8 uuid[BTRFS_UUID_SIZE];
107 
108 	/*
109 	 * size of the device on the current transaction
110 	 *
111 	 * This variant is update when committing the transaction,
112 	 * and protected by chunk mutex
113 	 */
114 	u64 commit_total_bytes;
115 
116 	/* bytes used on the current transaction */
117 	u64 commit_bytes_used;
118 
119 	/* for sending down flush barriers */
120 	struct bio *flush_bio;
121 	struct completion flush_wait;
122 
123 	/* per-device scrub information */
124 	struct scrub_ctx *scrub_ctx;
125 
126 	/* disk I/O failure stats. For detailed description refer to
127 	 * enum btrfs_dev_stat_values in ioctl.h */
128 	int dev_stats_valid;
129 
130 	/* Counter to record the change of device stats */
131 	atomic_t dev_stats_ccnt;
132 	atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
133 
134 	struct extent_io_tree alloc_state;
135 
136 	struct completion kobj_unregister;
137 	/* For sysfs/FSID/devinfo/devid/ */
138 	struct kobject devid_kobj;
139 
140 	/* Bandwidth limit for scrub, in bytes */
141 	u64 scrub_speed_max;
142 };
143 
144 /*
145  * If we read those variants at the context of their own lock, we needn't
146  * use the following helpers, reading them directly is safe.
147  */
148 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
149 #define BTRFS_DEVICE_GETSET_FUNCS(name)					\
150 static inline u64							\
151 btrfs_device_get_##name(const struct btrfs_device *dev)			\
152 {									\
153 	u64 size;							\
154 	unsigned int seq;						\
155 									\
156 	do {								\
157 		seq = read_seqcount_begin(&dev->data_seqcount);		\
158 		size = dev->name;					\
159 	} while (read_seqcount_retry(&dev->data_seqcount, seq));	\
160 	return size;							\
161 }									\
162 									\
163 static inline void							\
164 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
165 {									\
166 	preempt_disable();						\
167 	write_seqcount_begin(&dev->data_seqcount);			\
168 	dev->name = size;						\
169 	write_seqcount_end(&dev->data_seqcount);			\
170 	preempt_enable();						\
171 }
172 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
173 #define BTRFS_DEVICE_GETSET_FUNCS(name)					\
174 static inline u64							\
175 btrfs_device_get_##name(const struct btrfs_device *dev)			\
176 {									\
177 	u64 size;							\
178 									\
179 	preempt_disable();						\
180 	size = dev->name;						\
181 	preempt_enable();						\
182 	return size;							\
183 }									\
184 									\
185 static inline void							\
186 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
187 {									\
188 	preempt_disable();						\
189 	dev->name = size;						\
190 	preempt_enable();						\
191 }
192 #else
193 #define BTRFS_DEVICE_GETSET_FUNCS(name)					\
194 static inline u64							\
195 btrfs_device_get_##name(const struct btrfs_device *dev)			\
196 {									\
197 	return dev->name;						\
198 }									\
199 									\
200 static inline void							\
201 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
202 {									\
203 	dev->name = size;						\
204 }
205 #endif
206 
207 BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
208 BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
209 BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
210 
211 enum btrfs_chunk_allocation_policy {
212 	BTRFS_CHUNK_ALLOC_REGULAR,
213 	BTRFS_CHUNK_ALLOC_ZONED,
214 };
215 
216 /*
217  * Read policies for mirrored block group profiles, read picks the stripe based
218  * on these policies.
219  */
220 enum btrfs_read_policy {
221 	/* Use process PID to choose the stripe */
222 	BTRFS_READ_POLICY_PID,
223 	BTRFS_NR_READ_POLICY,
224 };
225 
226 struct btrfs_fs_devices {
227 	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
228 	u8 metadata_uuid[BTRFS_FSID_SIZE];
229 	bool fsid_change;
230 	struct list_head fs_list;
231 
232 	/*
233 	 * Number of devices under this fsid including missing and
234 	 * replace-target device and excludes seed devices.
235 	 */
236 	u64 num_devices;
237 
238 	/*
239 	 * The number of devices that successfully opened, including
240 	 * replace-target, excludes seed devices.
241 	 */
242 	u64 open_devices;
243 
244 	/* The number of devices that are under the chunk allocation list. */
245 	u64 rw_devices;
246 
247 	/* Count of missing devices under this fsid excluding seed device. */
248 	u64 missing_devices;
249 	u64 total_rw_bytes;
250 
251 	/*
252 	 * Count of devices from btrfs_super_block::num_devices for this fsid,
253 	 * which includes the seed device, excludes the transient replace-target
254 	 * device.
255 	 */
256 	u64 total_devices;
257 
258 	/* Highest generation number of seen devices */
259 	u64 latest_generation;
260 
261 	/*
262 	 * The mount device or a device with highest generation after removal
263 	 * or replace.
264 	 */
265 	struct btrfs_device *latest_dev;
266 
267 	/* all of the devices in the FS, protected by a mutex
268 	 * so we can safely walk it to write out the supers without
269 	 * worrying about add/remove by the multi-device code.
270 	 * Scrubbing super can kick off supers writing by holding
271 	 * this mutex lock.
272 	 */
273 	struct mutex device_list_mutex;
274 
275 	/* List of all devices, protected by device_list_mutex */
276 	struct list_head devices;
277 
278 	/*
279 	 * Devices which can satisfy space allocation. Protected by
280 	 * chunk_mutex
281 	 */
282 	struct list_head alloc_list;
283 
284 	struct list_head seed_list;
285 	bool seeding;
286 
287 	int opened;
288 
289 	/* set when we find or add a device that doesn't have the
290 	 * nonrot flag set
291 	 */
292 	bool rotating;
293 
294 	struct btrfs_fs_info *fs_info;
295 	/* sysfs kobjects */
296 	struct kobject fsid_kobj;
297 	struct kobject *devices_kobj;
298 	struct kobject *devinfo_kobj;
299 	struct completion kobj_unregister;
300 
301 	enum btrfs_chunk_allocation_policy chunk_alloc_policy;
302 
303 	/* Policy used to read the mirrored stripes */
304 	enum btrfs_read_policy read_policy;
305 };
306 
307 #define BTRFS_BIO_INLINE_CSUM_SIZE	64
308 
309 #define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info)	\
310 			- sizeof(struct btrfs_chunk))		\
311 			/ sizeof(struct btrfs_stripe) + 1)
312 
313 #define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE	\
314 				- 2 * sizeof(struct btrfs_disk_key)	\
315 				- 2 * sizeof(struct btrfs_chunk))	\
316 				/ sizeof(struct btrfs_stripe) + 1)
317 
318 /*
319  * Additional info to pass along bio.
320  *
321  * Mostly for btrfs specific features like csum and mirror_num.
322  */
323 struct btrfs_bio {
324 	unsigned int mirror_num;
325 
326 	/* @device is for stripe IO submission. */
327 	struct btrfs_device *device;
328 	u8 *csum;
329 	u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
330 	struct bvec_iter iter;
331 
332 	/*
333 	 * This member must come last, bio_alloc_bioset will allocate enough
334 	 * bytes for entire btrfs_bio but relies on bio being last.
335 	 */
336 	struct bio bio;
337 };
338 
339 static inline struct btrfs_bio *btrfs_bio(struct bio *bio)
340 {
341 	return container_of(bio, struct btrfs_bio, bio);
342 }
343 
344 static inline void btrfs_bio_free_csum(struct btrfs_bio *bbio)
345 {
346 	if (bbio->csum != bbio->csum_inline) {
347 		kfree(bbio->csum);
348 		bbio->csum = NULL;
349 	}
350 }
351 
352 struct btrfs_io_stripe {
353 	struct btrfs_device *dev;
354 	u64 physical;
355 	u64 length; /* only used for discard mappings */
356 };
357 
358 /*
359  * Context for IO subsmission for device stripe.
360  *
361  * - Track the unfinished mirrors for mirror based profiles
362  *   Mirror based profiles are SINGLE/DUP/RAID1/RAID10.
363  *
364  * - Contain the logical -> physical mapping info
365  *   Used by submit_stripe_bio() for mapping logical bio
366  *   into physical device address.
367  *
368  * - Contain device replace info
369  *   Used by handle_ops_on_dev_replace() to copy logical bios
370  *   into the new device.
371  *
372  * - Contain RAID56 full stripe logical bytenrs
373  */
374 struct btrfs_io_context {
375 	refcount_t refs;
376 	atomic_t stripes_pending;
377 	struct btrfs_fs_info *fs_info;
378 	u64 map_type; /* get from map_lookup->type */
379 	bio_end_io_t *end_io;
380 	struct bio *orig_bio;
381 	void *private;
382 	atomic_t error;
383 	int max_errors;
384 	int num_stripes;
385 	int mirror_num;
386 	int num_tgtdevs;
387 	int *tgtdev_map;
388 	/*
389 	 * logical block numbers for the start of each stripe
390 	 * The last one or two are p/q.  These are sorted,
391 	 * so raid_map[0] is the start of our full stripe
392 	 */
393 	u64 *raid_map;
394 	struct btrfs_io_stripe stripes[];
395 };
396 
397 struct btrfs_device_info {
398 	struct btrfs_device *dev;
399 	u64 dev_offset;
400 	u64 max_avail;
401 	u64 total_avail;
402 };
403 
404 struct btrfs_raid_attr {
405 	u8 sub_stripes;		/* sub_stripes info for map */
406 	u8 dev_stripes;		/* stripes per dev */
407 	u8 devs_max;		/* max devs to use */
408 	u8 devs_min;		/* min devs needed */
409 	u8 tolerated_failures;	/* max tolerated fail devs */
410 	u8 devs_increment;	/* ndevs has to be a multiple of this */
411 	u8 ncopies;		/* how many copies to data has */
412 	u8 nparity;		/* number of stripes worth of bytes to store
413 				 * parity information */
414 	u8 mindev_error;	/* error code if min devs requisite is unmet */
415 	const char raid_name[8]; /* name of the raid */
416 	u64 bg_flag;		/* block group flag of the raid */
417 };
418 
419 extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
420 
421 struct map_lookup {
422 	u64 type;
423 	int io_align;
424 	int io_width;
425 	u64 stripe_len;
426 	int num_stripes;
427 	int sub_stripes;
428 	int verified_stripes; /* For mount time dev extent verification */
429 	struct btrfs_io_stripe stripes[];
430 };
431 
432 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
433 			    (sizeof(struct btrfs_io_stripe) * (n)))
434 
435 struct btrfs_balance_args;
436 struct btrfs_balance_progress;
437 struct btrfs_balance_control {
438 	struct btrfs_balance_args data;
439 	struct btrfs_balance_args meta;
440 	struct btrfs_balance_args sys;
441 
442 	u64 flags;
443 
444 	struct btrfs_balance_progress stat;
445 };
446 
447 /*
448  * Search for a given device by the set parameters
449  */
450 struct btrfs_dev_lookup_args {
451 	u64 devid;
452 	u8 *uuid;
453 	u8 *fsid;
454 	bool missing;
455 };
456 
457 /* We have to initialize to -1 because BTRFS_DEV_REPLACE_DEVID is 0 */
458 #define BTRFS_DEV_LOOKUP_ARGS_INIT { .devid = (u64)-1 }
459 
460 #define BTRFS_DEV_LOOKUP_ARGS(name) \
461 	struct btrfs_dev_lookup_args name = BTRFS_DEV_LOOKUP_ARGS_INIT
462 
463 enum btrfs_map_op {
464 	BTRFS_MAP_READ,
465 	BTRFS_MAP_WRITE,
466 	BTRFS_MAP_DISCARD,
467 	BTRFS_MAP_GET_READ_MIRRORS,
468 };
469 
470 static inline enum btrfs_map_op btrfs_op(struct bio *bio)
471 {
472 	switch (bio_op(bio)) {
473 	case REQ_OP_DISCARD:
474 		return BTRFS_MAP_DISCARD;
475 	case REQ_OP_WRITE:
476 	case REQ_OP_ZONE_APPEND:
477 		return BTRFS_MAP_WRITE;
478 	default:
479 		WARN_ON_ONCE(1);
480 		fallthrough;
481 	case REQ_OP_READ:
482 		return BTRFS_MAP_READ;
483 	}
484 }
485 
486 void btrfs_get_bioc(struct btrfs_io_context *bioc);
487 void btrfs_put_bioc(struct btrfs_io_context *bioc);
488 int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
489 		    u64 logical, u64 *length,
490 		    struct btrfs_io_context **bioc_ret, int mirror_num);
491 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
492 		     u64 logical, u64 *length,
493 		     struct btrfs_io_context **bioc_ret);
494 int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, struct extent_map *map,
495 			  enum btrfs_map_op op, u64 logical,
496 			  struct btrfs_io_geometry *io_geom);
497 int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
498 int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
499 struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans,
500 					    u64 type);
501 void btrfs_mapping_tree_free(struct extent_map_tree *tree);
502 blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
503 			   int mirror_num);
504 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
505 		       fmode_t flags, void *holder);
506 struct btrfs_device *btrfs_scan_one_device(const char *path,
507 					   fmode_t flags, void *holder);
508 int btrfs_forget_devices(const char *path);
509 void btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
510 void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices);
511 void btrfs_assign_next_active_device(struct btrfs_device *device,
512 				     struct btrfs_device *this_dev);
513 struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
514 						  u64 devid,
515 						  const char *devpath);
516 int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
517 				 struct btrfs_dev_lookup_args *args,
518 				 const char *path);
519 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
520 					const u64 *devid,
521 					const u8 *uuid);
522 void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args);
523 void btrfs_free_device(struct btrfs_device *device);
524 int btrfs_rm_device(struct btrfs_fs_info *fs_info,
525 		    struct btrfs_dev_lookup_args *args,
526 		    struct block_device **bdev, fmode_t *mode);
527 void __exit btrfs_cleanup_fs_uuids(void);
528 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
529 int btrfs_grow_device(struct btrfs_trans_handle *trans,
530 		      struct btrfs_device *device, u64 new_size);
531 struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices,
532 				       const struct btrfs_dev_lookup_args *args);
533 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
534 int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
535 int btrfs_balance(struct btrfs_fs_info *fs_info,
536 		  struct btrfs_balance_control *bctl,
537 		  struct btrfs_ioctl_balance_args *bargs);
538 void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
539 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
540 int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
541 int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
542 int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset);
543 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
544 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
545 int btrfs_uuid_scan_kthread(void *data);
546 bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset);
547 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
548 			 u64 *start, u64 *max_avail);
549 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
550 int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
551 			struct btrfs_ioctl_get_dev_stats *stats);
552 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
553 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
554 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans);
555 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);
556 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);
557 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);
558 int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
559 			   u64 logical, u64 len);
560 unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
561 				    u64 logical);
562 int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans,
563 				     struct btrfs_block_group *bg);
564 int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);
565 struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
566 				       u64 logical, u64 length);
567 void btrfs_release_disk_super(struct btrfs_super_block *super);
568 
569 static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
570 				      int index)
571 {
572 	atomic_inc(dev->dev_stat_values + index);
573 	/*
574 	 * This memory barrier orders stores updating statistics before stores
575 	 * updating dev_stats_ccnt.
576 	 *
577 	 * It pairs with smp_rmb() in btrfs_run_dev_stats().
578 	 */
579 	smp_mb__before_atomic();
580 	atomic_inc(&dev->dev_stats_ccnt);
581 }
582 
583 static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
584 				      int index)
585 {
586 	return atomic_read(dev->dev_stat_values + index);
587 }
588 
589 static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
590 						int index)
591 {
592 	int ret;
593 
594 	ret = atomic_xchg(dev->dev_stat_values + index, 0);
595 	/*
596 	 * atomic_xchg implies a full memory barriers as per atomic_t.txt:
597 	 * - RMW operations that have a return value are fully ordered;
598 	 *
599 	 * This implicit memory barriers is paired with the smp_rmb in
600 	 * btrfs_run_dev_stats
601 	 */
602 	atomic_inc(&dev->dev_stats_ccnt);
603 	return ret;
604 }
605 
606 static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
607 				      int index, unsigned long val)
608 {
609 	atomic_set(dev->dev_stat_values + index, val);
610 	/*
611 	 * This memory barrier orders stores updating statistics before stores
612 	 * updating dev_stats_ccnt.
613 	 *
614 	 * It pairs with smp_rmb() in btrfs_run_dev_stats().
615 	 */
616 	smp_mb__before_atomic();
617 	atomic_inc(&dev->dev_stats_ccnt);
618 }
619 
620 void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
621 
622 struct list_head * __attribute_const__ btrfs_get_fs_uuids(void);
623 bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
624 					struct btrfs_device *failing_dev);
625 void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info,
626 			       struct block_device *bdev,
627 			       const char *device_path);
628 
629 enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags);
630 int btrfs_bg_type_to_factor(u64 flags);
631 const char *btrfs_bg_type_to_raid_name(u64 flags);
632 int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
633 bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical);
634 
635 #endif
636