xref: /linux/fs/btrfs/volumes.h (revision 23c48a124b469cee2eb0c75e6d22d366d1caa118)
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 /* Used by sanity check for btrfs_raid_types. */
21 #define const_ffs(n) (__builtin_ctzll(n) + 1)
22 
23 /*
24  * The conversion from BTRFS_BLOCK_GROUP_* bits to btrfs_raid_type requires
25  * RAID0 always to be the lowest profile bit.
26  * Although it's part of on-disk format and should never change, do extra
27  * compile-time sanity checks.
28  */
29 static_assert(const_ffs(BTRFS_BLOCK_GROUP_RAID0) <
30 	      const_ffs(BTRFS_BLOCK_GROUP_PROFILE_MASK & ~BTRFS_BLOCK_GROUP_RAID0));
31 static_assert(const_ilog2(BTRFS_BLOCK_GROUP_RAID0) >
32 	      ilog2(BTRFS_BLOCK_GROUP_TYPE_MASK));
33 
34 /* ilog2() can handle both constants and variables */
35 #define BTRFS_BG_FLAG_TO_INDEX(profile)					\
36 	ilog2((profile) >> (ilog2(BTRFS_BLOCK_GROUP_RAID0) - 1))
37 
38 enum btrfs_raid_types {
39 	/* SINGLE is the special one as it doesn't have on-disk bit. */
40 	BTRFS_RAID_SINGLE  = 0,
41 
42 	BTRFS_RAID_RAID0   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID0),
43 	BTRFS_RAID_RAID1   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1),
44 	BTRFS_RAID_DUP	   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_DUP),
45 	BTRFS_RAID_RAID10  = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID10),
46 	BTRFS_RAID_RAID5   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID5),
47 	BTRFS_RAID_RAID6   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID6),
48 	BTRFS_RAID_RAID1C3 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C3),
49 	BTRFS_RAID_RAID1C4 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C4),
50 
51 	BTRFS_NR_RAID_TYPES
52 };
53 
54 struct btrfs_io_geometry {
55 	/* remaining bytes before crossing a stripe */
56 	u64 len;
57 	/* offset of logical address in chunk */
58 	u64 offset;
59 	/* length of single IO stripe */
60 	u32 stripe_len;
61 	/* offset of address in stripe */
62 	u32 stripe_offset;
63 	/* number of stripe where address falls */
64 	u64 stripe_nr;
65 	/* offset of raid56 stripe into the chunk */
66 	u64 raid56_stripe_offset;
67 };
68 
69 /*
70  * Use sequence counter to get consistent device stat data on
71  * 32-bit processors.
72  */
73 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
74 #include <linux/seqlock.h>
75 #define __BTRFS_NEED_DEVICE_DATA_ORDERED
76 #define btrfs_device_data_ordered_init(device)	\
77 	seqcount_init(&device->data_seqcount)
78 #else
79 #define btrfs_device_data_ordered_init(device) do { } while (0)
80 #endif
81 
82 #define BTRFS_DEV_STATE_WRITEABLE	(0)
83 #define BTRFS_DEV_STATE_IN_FS_METADATA	(1)
84 #define BTRFS_DEV_STATE_MISSING		(2)
85 #define BTRFS_DEV_STATE_REPLACE_TGT	(3)
86 #define BTRFS_DEV_STATE_FLUSH_SENT	(4)
87 #define BTRFS_DEV_STATE_NO_READA	(5)
88 
89 struct btrfs_zoned_device_info;
90 
91 struct btrfs_device {
92 	struct list_head dev_list; /* device_list_mutex */
93 	struct list_head dev_alloc_list; /* chunk mutex */
94 	struct list_head post_commit_list; /* chunk mutex */
95 	struct btrfs_fs_devices *fs_devices;
96 	struct btrfs_fs_info *fs_info;
97 
98 	struct rcu_string __rcu *name;
99 
100 	u64 generation;
101 
102 	struct block_device *bdev;
103 
104 	struct btrfs_zoned_device_info *zone_info;
105 
106 	/* the mode sent to blkdev_get */
107 	fmode_t mode;
108 
109 	/*
110 	 * Device's major-minor number. Must be set even if the device is not
111 	 * opened (bdev == NULL), unless the device is missing.
112 	 */
113 	dev_t devt;
114 	unsigned long dev_state;
115 	blk_status_t last_flush_error;
116 
117 #ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
118 	seqcount_t data_seqcount;
119 #endif
120 
121 	/* the internal btrfs device id */
122 	u64 devid;
123 
124 	/* size of the device in memory */
125 	u64 total_bytes;
126 
127 	/* size of the device on disk */
128 	u64 disk_total_bytes;
129 
130 	/* bytes used */
131 	u64 bytes_used;
132 
133 	/* optimal io alignment for this device */
134 	u32 io_align;
135 
136 	/* optimal io width for this device */
137 	u32 io_width;
138 	/* type and info about this device */
139 	u64 type;
140 
141 	/* minimal io size for this device */
142 	u32 sector_size;
143 
144 	/* physical drive uuid (or lvm uuid) */
145 	u8 uuid[BTRFS_UUID_SIZE];
146 
147 	/*
148 	 * size of the device on the current transaction
149 	 *
150 	 * This variant is update when committing the transaction,
151 	 * and protected by chunk mutex
152 	 */
153 	u64 commit_total_bytes;
154 
155 	/* bytes used on the current transaction */
156 	u64 commit_bytes_used;
157 
158 	/* Bio used for flushing device barriers */
159 	struct bio flush_bio;
160 	struct completion flush_wait;
161 
162 	/* per-device scrub information */
163 	struct scrub_ctx *scrub_ctx;
164 
165 	/* disk I/O failure stats. For detailed description refer to
166 	 * enum btrfs_dev_stat_values in ioctl.h */
167 	int dev_stats_valid;
168 
169 	/* Counter to record the change of device stats */
170 	atomic_t dev_stats_ccnt;
171 	atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
172 
173 	struct extent_io_tree alloc_state;
174 
175 	struct completion kobj_unregister;
176 	/* For sysfs/FSID/devinfo/devid/ */
177 	struct kobject devid_kobj;
178 
179 	/* Bandwidth limit for scrub, in bytes */
180 	u64 scrub_speed_max;
181 };
182 
183 /*
184  * If we read those variants at the context of their own lock, we needn't
185  * use the following helpers, reading them directly is safe.
186  */
187 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
188 #define BTRFS_DEVICE_GETSET_FUNCS(name)					\
189 static inline u64							\
190 btrfs_device_get_##name(const struct btrfs_device *dev)			\
191 {									\
192 	u64 size;							\
193 	unsigned int seq;						\
194 									\
195 	do {								\
196 		seq = read_seqcount_begin(&dev->data_seqcount);		\
197 		size = dev->name;					\
198 	} while (read_seqcount_retry(&dev->data_seqcount, seq));	\
199 	return size;							\
200 }									\
201 									\
202 static inline void							\
203 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
204 {									\
205 	preempt_disable();						\
206 	write_seqcount_begin(&dev->data_seqcount);			\
207 	dev->name = size;						\
208 	write_seqcount_end(&dev->data_seqcount);			\
209 	preempt_enable();						\
210 }
211 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
212 #define BTRFS_DEVICE_GETSET_FUNCS(name)					\
213 static inline u64							\
214 btrfs_device_get_##name(const struct btrfs_device *dev)			\
215 {									\
216 	u64 size;							\
217 									\
218 	preempt_disable();						\
219 	size = dev->name;						\
220 	preempt_enable();						\
221 	return size;							\
222 }									\
223 									\
224 static inline void							\
225 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
226 {									\
227 	preempt_disable();						\
228 	dev->name = size;						\
229 	preempt_enable();						\
230 }
231 #else
232 #define BTRFS_DEVICE_GETSET_FUNCS(name)					\
233 static inline u64							\
234 btrfs_device_get_##name(const struct btrfs_device *dev)			\
235 {									\
236 	return dev->name;						\
237 }									\
238 									\
239 static inline void							\
240 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
241 {									\
242 	dev->name = size;						\
243 }
244 #endif
245 
246 BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
247 BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
248 BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
249 
250 enum btrfs_chunk_allocation_policy {
251 	BTRFS_CHUNK_ALLOC_REGULAR,
252 	BTRFS_CHUNK_ALLOC_ZONED,
253 };
254 
255 /*
256  * Read policies for mirrored block group profiles, read picks the stripe based
257  * on these policies.
258  */
259 enum btrfs_read_policy {
260 	/* Use process PID to choose the stripe */
261 	BTRFS_READ_POLICY_PID,
262 	BTRFS_NR_READ_POLICY,
263 };
264 
265 struct btrfs_fs_devices {
266 	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
267 	u8 metadata_uuid[BTRFS_FSID_SIZE];
268 	bool fsid_change;
269 	struct list_head fs_list;
270 
271 	/*
272 	 * Number of devices under this fsid including missing and
273 	 * replace-target device and excludes seed devices.
274 	 */
275 	u64 num_devices;
276 
277 	/*
278 	 * The number of devices that successfully opened, including
279 	 * replace-target, excludes seed devices.
280 	 */
281 	u64 open_devices;
282 
283 	/* The number of devices that are under the chunk allocation list. */
284 	u64 rw_devices;
285 
286 	/* Count of missing devices under this fsid excluding seed device. */
287 	u64 missing_devices;
288 	u64 total_rw_bytes;
289 
290 	/*
291 	 * Count of devices from btrfs_super_block::num_devices for this fsid,
292 	 * which includes the seed device, excludes the transient replace-target
293 	 * device.
294 	 */
295 	u64 total_devices;
296 
297 	/* Highest generation number of seen devices */
298 	u64 latest_generation;
299 
300 	/*
301 	 * The mount device or a device with highest generation after removal
302 	 * or replace.
303 	 */
304 	struct btrfs_device *latest_dev;
305 
306 	/* all of the devices in the FS, protected by a mutex
307 	 * so we can safely walk it to write out the supers without
308 	 * worrying about add/remove by the multi-device code.
309 	 * Scrubbing super can kick off supers writing by holding
310 	 * this mutex lock.
311 	 */
312 	struct mutex device_list_mutex;
313 
314 	/* List of all devices, protected by device_list_mutex */
315 	struct list_head devices;
316 
317 	/*
318 	 * Devices which can satisfy space allocation. Protected by
319 	 * chunk_mutex
320 	 */
321 	struct list_head alloc_list;
322 
323 	struct list_head seed_list;
324 	bool seeding;
325 
326 	int opened;
327 
328 	/* set when we find or add a device that doesn't have the
329 	 * nonrot flag set
330 	 */
331 	bool rotating;
332 
333 	struct btrfs_fs_info *fs_info;
334 	/* sysfs kobjects */
335 	struct kobject fsid_kobj;
336 	struct kobject *devices_kobj;
337 	struct kobject *devinfo_kobj;
338 	struct completion kobj_unregister;
339 
340 	enum btrfs_chunk_allocation_policy chunk_alloc_policy;
341 
342 	/* Policy used to read the mirrored stripes */
343 	enum btrfs_read_policy read_policy;
344 };
345 
346 #define BTRFS_BIO_INLINE_CSUM_SIZE	64
347 
348 #define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info)	\
349 			- sizeof(struct btrfs_chunk))		\
350 			/ sizeof(struct btrfs_stripe) + 1)
351 
352 #define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE	\
353 				- 2 * sizeof(struct btrfs_disk_key)	\
354 				- 2 * sizeof(struct btrfs_chunk))	\
355 				/ sizeof(struct btrfs_stripe) + 1)
356 
357 /*
358  * Maximum number of sectors for a single bio to limit the size of the
359  * checksum array.  This matches the number of bio_vecs per bio and thus the
360  * I/O size for buffered I/O.
361  */
362 #define BTRFS_MAX_BIO_SECTORS				(256)
363 
364 /*
365  * Additional info to pass along bio.
366  *
367  * Mostly for btrfs specific features like csum and mirror_num.
368  */
369 struct btrfs_bio {
370 	unsigned int mirror_num;
371 
372 	/* for direct I/O */
373 	u64 file_offset;
374 
375 	/* @device is for stripe IO submission. */
376 	struct btrfs_device *device;
377 	u8 *csum;
378 	u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
379 	struct bvec_iter iter;
380 
381 	/* For read end I/O handling */
382 	struct work_struct end_io_work;
383 
384 	/*
385 	 * This member must come last, bio_alloc_bioset will allocate enough
386 	 * bytes for entire btrfs_bio but relies on bio being last.
387 	 */
388 	struct bio bio;
389 };
390 
391 static inline struct btrfs_bio *btrfs_bio(struct bio *bio)
392 {
393 	return container_of(bio, struct btrfs_bio, bio);
394 }
395 
396 static inline void btrfs_bio_free_csum(struct btrfs_bio *bbio)
397 {
398 	if (bbio->csum != bbio->csum_inline) {
399 		kfree(bbio->csum);
400 		bbio->csum = NULL;
401 	}
402 }
403 
404 /*
405  * Iterate through a btrfs_bio (@bbio) on a per-sector basis.
406  *
407  * bvl        - struct bio_vec
408  * bbio       - struct btrfs_bio
409  * iters      - struct bvec_iter
410  * bio_offset - unsigned int
411  */
412 #define btrfs_bio_for_each_sector(fs_info, bvl, bbio, iter, bio_offset)	\
413 	for ((iter) = (bbio)->iter, (bio_offset) = 0;			\
414 	     (iter).bi_size &&					\
415 	     (((bvl) = bio_iter_iovec((&(bbio)->bio), (iter))), 1);	\
416 	     (bio_offset) += fs_info->sectorsize,			\
417 	     bio_advance_iter_single(&(bbio)->bio, &(iter),		\
418 	     (fs_info)->sectorsize))
419 
420 struct btrfs_io_stripe {
421 	struct btrfs_device *dev;
422 	union {
423 		/* Block mapping */
424 		u64 physical;
425 		/* For the endio handler */
426 		struct btrfs_io_context *bioc;
427 	};
428 };
429 
430 struct btrfs_discard_stripe {
431 	struct btrfs_device *dev;
432 	u64 physical;
433 	u64 length;
434 };
435 
436 /*
437  * Context for IO subsmission for device stripe.
438  *
439  * - Track the unfinished mirrors for mirror based profiles
440  *   Mirror based profiles are SINGLE/DUP/RAID1/RAID10.
441  *
442  * - Contain the logical -> physical mapping info
443  *   Used by submit_stripe_bio() for mapping logical bio
444  *   into physical device address.
445  *
446  * - Contain device replace info
447  *   Used by handle_ops_on_dev_replace() to copy logical bios
448  *   into the new device.
449  *
450  * - Contain RAID56 full stripe logical bytenrs
451  */
452 struct btrfs_io_context {
453 	refcount_t refs;
454 	atomic_t stripes_pending;
455 	struct btrfs_fs_info *fs_info;
456 	u64 map_type; /* get from map_lookup->type */
457 	bio_end_io_t *end_io;
458 	struct bio *orig_bio;
459 	void *private;
460 	atomic_t error;
461 	int max_errors;
462 	int num_stripes;
463 	int mirror_num;
464 	int num_tgtdevs;
465 	int *tgtdev_map;
466 	/*
467 	 * logical block numbers for the start of each stripe
468 	 * The last one or two are p/q.  These are sorted,
469 	 * so raid_map[0] is the start of our full stripe
470 	 */
471 	u64 *raid_map;
472 	struct btrfs_io_stripe stripes[];
473 };
474 
475 struct btrfs_device_info {
476 	struct btrfs_device *dev;
477 	u64 dev_offset;
478 	u64 max_avail;
479 	u64 total_avail;
480 };
481 
482 struct btrfs_raid_attr {
483 	u8 sub_stripes;		/* sub_stripes info for map */
484 	u8 dev_stripes;		/* stripes per dev */
485 	u8 devs_max;		/* max devs to use */
486 	u8 devs_min;		/* min devs needed */
487 	u8 tolerated_failures;	/* max tolerated fail devs */
488 	u8 devs_increment;	/* ndevs has to be a multiple of this */
489 	u8 ncopies;		/* how many copies to data has */
490 	u8 nparity;		/* number of stripes worth of bytes to store
491 				 * parity information */
492 	u8 mindev_error;	/* error code if min devs requisite is unmet */
493 	const char raid_name[8]; /* name of the raid */
494 	u64 bg_flag;		/* block group flag of the raid */
495 };
496 
497 extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
498 
499 struct map_lookup {
500 	u64 type;
501 	int io_align;
502 	int io_width;
503 	u32 stripe_len;
504 	int num_stripes;
505 	int sub_stripes;
506 	int verified_stripes; /* For mount time dev extent verification */
507 	struct btrfs_io_stripe stripes[];
508 };
509 
510 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
511 			    (sizeof(struct btrfs_io_stripe) * (n)))
512 
513 struct btrfs_balance_args;
514 struct btrfs_balance_progress;
515 struct btrfs_balance_control {
516 	struct btrfs_balance_args data;
517 	struct btrfs_balance_args meta;
518 	struct btrfs_balance_args sys;
519 
520 	u64 flags;
521 
522 	struct btrfs_balance_progress stat;
523 };
524 
525 /*
526  * Search for a given device by the set parameters
527  */
528 struct btrfs_dev_lookup_args {
529 	u64 devid;
530 	u8 *uuid;
531 	u8 *fsid;
532 	bool missing;
533 };
534 
535 /* We have to initialize to -1 because BTRFS_DEV_REPLACE_DEVID is 0 */
536 #define BTRFS_DEV_LOOKUP_ARGS_INIT { .devid = (u64)-1 }
537 
538 #define BTRFS_DEV_LOOKUP_ARGS(name) \
539 	struct btrfs_dev_lookup_args name = BTRFS_DEV_LOOKUP_ARGS_INIT
540 
541 enum btrfs_map_op {
542 	BTRFS_MAP_READ,
543 	BTRFS_MAP_WRITE,
544 	BTRFS_MAP_DISCARD,
545 	BTRFS_MAP_GET_READ_MIRRORS,
546 };
547 
548 static inline enum btrfs_map_op btrfs_op(struct bio *bio)
549 {
550 	switch (bio_op(bio)) {
551 	case REQ_OP_DISCARD:
552 		return BTRFS_MAP_DISCARD;
553 	case REQ_OP_WRITE:
554 	case REQ_OP_ZONE_APPEND:
555 		return BTRFS_MAP_WRITE;
556 	default:
557 		WARN_ON_ONCE(1);
558 		fallthrough;
559 	case REQ_OP_READ:
560 		return BTRFS_MAP_READ;
561 	}
562 }
563 
564 void btrfs_get_bioc(struct btrfs_io_context *bioc);
565 void btrfs_put_bioc(struct btrfs_io_context *bioc);
566 int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
567 		    u64 logical, u64 *length,
568 		    struct btrfs_io_context **bioc_ret, int mirror_num);
569 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
570 		     u64 logical, u64 *length,
571 		     struct btrfs_io_context **bioc_ret);
572 struct btrfs_discard_stripe *btrfs_map_discard(struct btrfs_fs_info *fs_info,
573 					       u64 logical, u64 *length_ret,
574 					       u32 *num_stripes);
575 int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, struct extent_map *map,
576 			  enum btrfs_map_op op, u64 logical,
577 			  struct btrfs_io_geometry *io_geom);
578 int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
579 int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
580 struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans,
581 					    u64 type);
582 void btrfs_mapping_tree_free(struct extent_map_tree *tree);
583 void btrfs_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio, int mirror_num);
584 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
585 		       fmode_t flags, void *holder);
586 struct btrfs_device *btrfs_scan_one_device(const char *path,
587 					   fmode_t flags, void *holder);
588 int btrfs_forget_devices(dev_t devt);
589 void btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
590 void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices);
591 void btrfs_assign_next_active_device(struct btrfs_device *device,
592 				     struct btrfs_device *this_dev);
593 struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
594 						  u64 devid,
595 						  const char *devpath);
596 int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
597 				 struct btrfs_dev_lookup_args *args,
598 				 const char *path);
599 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
600 					const u64 *devid,
601 					const u8 *uuid);
602 void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args);
603 void btrfs_free_device(struct btrfs_device *device);
604 int btrfs_rm_device(struct btrfs_fs_info *fs_info,
605 		    struct btrfs_dev_lookup_args *args,
606 		    struct block_device **bdev, fmode_t *mode);
607 void __exit btrfs_cleanup_fs_uuids(void);
608 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
609 int btrfs_grow_device(struct btrfs_trans_handle *trans,
610 		      struct btrfs_device *device, u64 new_size);
611 struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices,
612 				       const struct btrfs_dev_lookup_args *args);
613 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
614 int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
615 int btrfs_balance(struct btrfs_fs_info *fs_info,
616 		  struct btrfs_balance_control *bctl,
617 		  struct btrfs_ioctl_balance_args *bargs);
618 void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
619 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
620 int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
621 int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
622 int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset);
623 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
624 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
625 int btrfs_uuid_scan_kthread(void *data);
626 bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset);
627 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
628 			 u64 *start, u64 *max_avail);
629 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
630 int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
631 			struct btrfs_ioctl_get_dev_stats *stats);
632 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
633 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
634 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans);
635 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);
636 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);
637 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);
638 int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
639 			   u64 logical, u64 len);
640 unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
641 				    u64 logical);
642 u64 btrfs_calc_stripe_length(const struct extent_map *em);
643 int btrfs_nr_parity_stripes(u64 type);
644 int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans,
645 				     struct btrfs_block_group *bg);
646 int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);
647 struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
648 				       u64 logical, u64 length);
649 void btrfs_release_disk_super(struct btrfs_super_block *super);
650 
651 static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
652 				      int index)
653 {
654 	atomic_inc(dev->dev_stat_values + index);
655 	/*
656 	 * This memory barrier orders stores updating statistics before stores
657 	 * updating dev_stats_ccnt.
658 	 *
659 	 * It pairs with smp_rmb() in btrfs_run_dev_stats().
660 	 */
661 	smp_mb__before_atomic();
662 	atomic_inc(&dev->dev_stats_ccnt);
663 }
664 
665 static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
666 				      int index)
667 {
668 	return atomic_read(dev->dev_stat_values + index);
669 }
670 
671 static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
672 						int index)
673 {
674 	int ret;
675 
676 	ret = atomic_xchg(dev->dev_stat_values + index, 0);
677 	/*
678 	 * atomic_xchg implies a full memory barriers as per atomic_t.txt:
679 	 * - RMW operations that have a return value are fully ordered;
680 	 *
681 	 * This implicit memory barriers is paired with the smp_rmb in
682 	 * btrfs_run_dev_stats
683 	 */
684 	atomic_inc(&dev->dev_stats_ccnt);
685 	return ret;
686 }
687 
688 static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
689 				      int index, unsigned long val)
690 {
691 	atomic_set(dev->dev_stat_values + index, val);
692 	/*
693 	 * This memory barrier orders stores updating statistics before stores
694 	 * updating dev_stats_ccnt.
695 	 *
696 	 * It pairs with smp_rmb() in btrfs_run_dev_stats().
697 	 */
698 	smp_mb__before_atomic();
699 	atomic_inc(&dev->dev_stats_ccnt);
700 }
701 
702 void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
703 
704 struct list_head * __attribute_const__ btrfs_get_fs_uuids(void);
705 bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
706 					struct btrfs_device *failing_dev);
707 void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info,
708 			       struct block_device *bdev,
709 			       const char *device_path);
710 
711 enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags);
712 int btrfs_bg_type_to_factor(u64 flags);
713 const char *btrfs_bg_type_to_raid_name(u64 flags);
714 int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
715 bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical);
716 
717 #endif
718