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