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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/sort.h>
10#include <linux/btrfs.h>
11#include "async-thread.h"
12#include "messages.h"
13#include "tree-checker.h"
14#include "rcu-string.h"
15
16#define BTRFS_MAX_DATA_CHUNK_SIZE (10ULL * SZ_1G)
17
18extern struct mutex uuid_mutex;
19
20#define BTRFS_STRIPE_LEN SZ_64K
21
22/* Used by sanity check for btrfs_raid_types. */
23#define const_ffs(n) (__builtin_ctzll(n) + 1)
24
25/*
26 * The conversion from BTRFS_BLOCK_GROUP_* bits to btrfs_raid_type requires
27 * RAID0 always to be the lowest profile bit.
28 * Although it's part of on-disk format and should never change, do extra
29 * compile-time sanity checks.
30 */
31static_assert(const_ffs(BTRFS_BLOCK_GROUP_RAID0) <
32 const_ffs(BTRFS_BLOCK_GROUP_PROFILE_MASK & ~BTRFS_BLOCK_GROUP_RAID0));
33static_assert(const_ilog2(BTRFS_BLOCK_GROUP_RAID0) >
34 ilog2(BTRFS_BLOCK_GROUP_TYPE_MASK));
35
36/* ilog2() can handle both constants and variables */
37#define BTRFS_BG_FLAG_TO_INDEX(profile) \
38 ilog2((profile) >> (ilog2(BTRFS_BLOCK_GROUP_RAID0) - 1))
39
40enum btrfs_raid_types {
41 /* SINGLE is the special one as it doesn't have on-disk bit. */
42 BTRFS_RAID_SINGLE = 0,
43
44 BTRFS_RAID_RAID0 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID0),
45 BTRFS_RAID_RAID1 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1),
46 BTRFS_RAID_DUP = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_DUP),
47 BTRFS_RAID_RAID10 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID10),
48 BTRFS_RAID_RAID5 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID5),
49 BTRFS_RAID_RAID6 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID6),
50 BTRFS_RAID_RAID1C3 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C3),
51 BTRFS_RAID_RAID1C4 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C4),
52
53 BTRFS_NR_RAID_TYPES
54};
55
56struct btrfs_io_geometry {
57 /* remaining bytes before crossing a stripe */
58 u64 len;
59 /* offset of logical address in chunk */
60 u64 offset;
61 /* length of single IO stripe */
62 u32 stripe_len;
63 /* offset of address in stripe */
64 u32 stripe_offset;
65 /* number of stripe where address falls */
66 u64 stripe_nr;
67 /* offset of raid56 stripe into the chunk */
68 u64 raid56_stripe_offset;
69};
70
71/*
72 * Use sequence counter to get consistent device stat data on
73 * 32-bit processors.
74 */
75#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
76#include <linux/seqlock.h>
77#define __BTRFS_NEED_DEVICE_DATA_ORDERED
78#define btrfs_device_data_ordered_init(device) \
79 seqcount_init(&device->data_seqcount)
80#else
81#define btrfs_device_data_ordered_init(device) do { } while (0)
82#endif
83
84#define BTRFS_DEV_STATE_WRITEABLE (0)
85#define BTRFS_DEV_STATE_IN_FS_METADATA (1)
86#define BTRFS_DEV_STATE_MISSING (2)
87#define BTRFS_DEV_STATE_REPLACE_TGT (3)
88#define BTRFS_DEV_STATE_FLUSH_SENT (4)
89#define BTRFS_DEV_STATE_NO_READA (5)
90
91struct btrfs_zoned_device_info;
92
93struct btrfs_device {
94 struct list_head dev_list; /* device_list_mutex */
95 struct list_head dev_alloc_list; /* chunk mutex */
96 struct list_head post_commit_list; /* chunk mutex */
97 struct btrfs_fs_devices *fs_devices;
98 struct btrfs_fs_info *fs_info;
99
100 struct rcu_string __rcu *name;
101
102 u64 generation;
103
104 struct block_device *bdev;
105
106 struct btrfs_zoned_device_info *zone_info;
107
108 /* the mode sent to blkdev_get */
109 fmode_t mode;
110
111 /*
112 * Device's major-minor number. Must be set even if the device is not
113 * opened (bdev == NULL), unless the device is missing.
114 */
115 dev_t devt;
116 unsigned long dev_state;
117 blk_status_t last_flush_error;
118
119#ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
120 seqcount_t data_seqcount;
121#endif
122
123 /* the internal btrfs device id */
124 u64 devid;
125
126 /* size of the device in memory */
127 u64 total_bytes;
128
129 /* size of the device on disk */
130 u64 disk_total_bytes;
131
132 /* bytes used */
133 u64 bytes_used;
134
135 /* optimal io alignment for this device */
136 u32 io_align;
137
138 /* optimal io width for this device */
139 u32 io_width;
140 /* type and info about this device */
141 u64 type;
142
143 /* minimal io size for this device */
144 u32 sector_size;
145
146 /* physical drive uuid (or lvm uuid) */
147 u8 uuid[BTRFS_UUID_SIZE];
148
149 /*
150 * size of the device on the current transaction
151 *
152 * This variant is update when committing the transaction,
153 * and protected by chunk mutex
154 */
155 u64 commit_total_bytes;
156
157 /* bytes used on the current transaction */
158 u64 commit_bytes_used;
159
160 /* Bio used for flushing device barriers */
161 struct bio flush_bio;
162 struct completion flush_wait;
163
164 /* per-device scrub information */
165 struct scrub_ctx *scrub_ctx;
166
167 /* disk I/O failure stats. For detailed description refer to
168 * enum btrfs_dev_stat_values in ioctl.h */
169 int dev_stats_valid;
170
171 /* Counter to record the change of device stats */
172 atomic_t dev_stats_ccnt;
173 atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
174
175 struct extent_io_tree alloc_state;
176
177 struct completion kobj_unregister;
178 /* For sysfs/FSID/devinfo/devid/ */
179 struct kobject devid_kobj;
180
181 /* Bandwidth limit for scrub, in bytes */
182 u64 scrub_speed_max;
183};
184
185/*
186 * Block group or device which contains an active swapfile. Used for preventing
187 * unsafe operations while a swapfile is active.
188 *
189 * These are sorted on (ptr, inode) (note that a block group or device can
190 * contain more than one swapfile). We compare the pointer values because we
191 * don't actually care what the object is, we just need a quick check whether
192 * the object exists in the rbtree.
193 */
194struct btrfs_swapfile_pin {
195 struct rb_node node;
196 void *ptr;
197 struct inode *inode;
198 /*
199 * If true, ptr points to a struct btrfs_block_group. Otherwise, ptr
200 * points to a struct btrfs_device.
201 */
202 bool is_block_group;
203 /*
204 * Only used when 'is_block_group' is true and it is the number of
205 * extents used by a swapfile for this block group ('ptr' field).
206 */
207 int bg_extent_count;
208};
209
210/*
211 * If we read those variants at the context of their own lock, we needn't
212 * use the following helpers, reading them directly is safe.
213 */
214#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
215#define BTRFS_DEVICE_GETSET_FUNCS(name) \
216static inline u64 \
217btrfs_device_get_##name(const struct btrfs_device *dev) \
218{ \
219 u64 size; \
220 unsigned int seq; \
221 \
222 do { \
223 seq = read_seqcount_begin(&dev->data_seqcount); \
224 size = dev->name; \
225 } while (read_seqcount_retry(&dev->data_seqcount, seq)); \
226 return size; \
227} \
228 \
229static inline void \
230btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
231{ \
232 preempt_disable(); \
233 write_seqcount_begin(&dev->data_seqcount); \
234 dev->name = size; \
235 write_seqcount_end(&dev->data_seqcount); \
236 preempt_enable(); \
237}
238#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
239#define BTRFS_DEVICE_GETSET_FUNCS(name) \
240static inline u64 \
241btrfs_device_get_##name(const struct btrfs_device *dev) \
242{ \
243 u64 size; \
244 \
245 preempt_disable(); \
246 size = dev->name; \
247 preempt_enable(); \
248 return size; \
249} \
250 \
251static inline void \
252btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
253{ \
254 preempt_disable(); \
255 dev->name = size; \
256 preempt_enable(); \
257}
258#else
259#define BTRFS_DEVICE_GETSET_FUNCS(name) \
260static inline u64 \
261btrfs_device_get_##name(const struct btrfs_device *dev) \
262{ \
263 return dev->name; \
264} \
265 \
266static inline void \
267btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
268{ \
269 dev->name = size; \
270}
271#endif
272
273BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
274BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
275BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
276
277enum btrfs_chunk_allocation_policy {
278 BTRFS_CHUNK_ALLOC_REGULAR,
279 BTRFS_CHUNK_ALLOC_ZONED,
280};
281
282/*
283 * Read policies for mirrored block group profiles, read picks the stripe based
284 * on these policies.
285 */
286enum btrfs_read_policy {
287 /* Use process PID to choose the stripe */
288 BTRFS_READ_POLICY_PID,
289 BTRFS_NR_READ_POLICY,
290};
291
292struct btrfs_fs_devices {
293 u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
294 u8 metadata_uuid[BTRFS_FSID_SIZE];
295 bool fsid_change;
296 struct list_head fs_list;
297
298 /*
299 * Number of devices under this fsid including missing and
300 * replace-target device and excludes seed devices.
301 */
302 u64 num_devices;
303
304 /*
305 * The number of devices that successfully opened, including
306 * replace-target, excludes seed devices.
307 */
308 u64 open_devices;
309
310 /* The number of devices that are under the chunk allocation list. */
311 u64 rw_devices;
312
313 /* Count of missing devices under this fsid excluding seed device. */
314 u64 missing_devices;
315 u64 total_rw_bytes;
316
317 /*
318 * Count of devices from btrfs_super_block::num_devices for this fsid,
319 * which includes the seed device, excludes the transient replace-target
320 * device.
321 */
322 u64 total_devices;
323
324 /* Highest generation number of seen devices */
325 u64 latest_generation;
326
327 /*
328 * The mount device or a device with highest generation after removal
329 * or replace.
330 */
331 struct btrfs_device *latest_dev;
332
333 /* all of the devices in the FS, protected by a mutex
334 * so we can safely walk it to write out the supers without
335 * worrying about add/remove by the multi-device code.
336 * Scrubbing super can kick off supers writing by holding
337 * this mutex lock.
338 */
339 struct mutex device_list_mutex;
340
341 /* List of all devices, protected by device_list_mutex */
342 struct list_head devices;
343
344 /*
345 * Devices which can satisfy space allocation. Protected by
346 * chunk_mutex
347 */
348 struct list_head alloc_list;
349
350 struct list_head seed_list;
351 bool seeding;
352
353 int opened;
354
355 /* set when we find or add a device that doesn't have the
356 * nonrot flag set
357 */
358 bool rotating;
359 /* Devices support TRIM/discard commands */
360 bool discardable;
361
362 struct btrfs_fs_info *fs_info;
363 /* sysfs kobjects */
364 struct kobject fsid_kobj;
365 struct kobject *devices_kobj;
366 struct kobject *devinfo_kobj;
367 struct completion kobj_unregister;
368
369 enum btrfs_chunk_allocation_policy chunk_alloc_policy;
370
371 /* Policy used to read the mirrored stripes */
372 enum btrfs_read_policy read_policy;
373};
374
375#define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info) \
376 - sizeof(struct btrfs_chunk)) \
377 / sizeof(struct btrfs_stripe) + 1)
378
379#define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE \
380 - 2 * sizeof(struct btrfs_disk_key) \
381 - 2 * sizeof(struct btrfs_chunk)) \
382 / sizeof(struct btrfs_stripe) + 1)
383
384struct btrfs_io_stripe {
385 struct btrfs_device *dev;
386 union {
387 /* Block mapping */
388 u64 physical;
389 /* For the endio handler */
390 struct btrfs_io_context *bioc;
391 };
392};
393
394struct btrfs_discard_stripe {
395 struct btrfs_device *dev;
396 u64 physical;
397 u64 length;
398};
399
400/*
401 * Context for IO subsmission for device stripe.
402 *
403 * - Track the unfinished mirrors for mirror based profiles
404 * Mirror based profiles are SINGLE/DUP/RAID1/RAID10.
405 *
406 * - Contain the logical -> physical mapping info
407 * Used by submit_stripe_bio() for mapping logical bio
408 * into physical device address.
409 *
410 * - Contain device replace info
411 * Used by handle_ops_on_dev_replace() to copy logical bios
412 * into the new device.
413 *
414 * - Contain RAID56 full stripe logical bytenrs
415 */
416struct btrfs_io_context {
417 refcount_t refs;
418 struct btrfs_fs_info *fs_info;
419 u64 map_type; /* get from map_lookup->type */
420 struct bio *orig_bio;
421 atomic_t error;
422 int max_errors;
423 int num_stripes;
424 int mirror_num;
425 int num_tgtdevs;
426 int *tgtdev_map;
427 /*
428 * logical block numbers for the start of each stripe
429 * The last one or two are p/q. These are sorted,
430 * so raid_map[0] is the start of our full stripe
431 */
432 u64 *raid_map;
433 struct btrfs_io_stripe stripes[];
434};
435
436struct btrfs_device_info {
437 struct btrfs_device *dev;
438 u64 dev_offset;
439 u64 max_avail;
440 u64 total_avail;
441};
442
443struct btrfs_raid_attr {
444 u8 sub_stripes; /* sub_stripes info for map */
445 u8 dev_stripes; /* stripes per dev */
446 u8 devs_max; /* max devs to use */
447 u8 devs_min; /* min devs needed */
448 u8 tolerated_failures; /* max tolerated fail devs */
449 u8 devs_increment; /* ndevs has to be a multiple of this */
450 u8 ncopies; /* how many copies to data has */
451 u8 nparity; /* number of stripes worth of bytes to store
452 * parity information */
453 u8 mindev_error; /* error code if min devs requisite is unmet */
454 const char raid_name[8]; /* name of the raid */
455 u64 bg_flag; /* block group flag of the raid */
456};
457
458extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
459
460struct map_lookup {
461 u64 type;
462 int io_align;
463 int io_width;
464 u32 stripe_len;
465 int num_stripes;
466 int sub_stripes;
467 int verified_stripes; /* For mount time dev extent verification */
468 struct btrfs_io_stripe stripes[];
469};
470
471#define map_lookup_size(n) (sizeof(struct map_lookup) + \
472 (sizeof(struct btrfs_io_stripe) * (n)))
473
474struct btrfs_balance_args;
475struct btrfs_balance_progress;
476struct btrfs_balance_control {
477 struct btrfs_balance_args data;
478 struct btrfs_balance_args meta;
479 struct btrfs_balance_args sys;
480
481 u64 flags;
482
483 struct btrfs_balance_progress stat;
484};
485
486/*
487 * Search for a given device by the set parameters
488 */
489struct btrfs_dev_lookup_args {
490 u64 devid;
491 u8 *uuid;
492 u8 *fsid;
493 bool missing;
494};
495
496/* We have to initialize to -1 because BTRFS_DEV_REPLACE_DEVID is 0 */
497#define BTRFS_DEV_LOOKUP_ARGS_INIT { .devid = (u64)-1 }
498
499#define BTRFS_DEV_LOOKUP_ARGS(name) \
500 struct btrfs_dev_lookup_args name = BTRFS_DEV_LOOKUP_ARGS_INIT
501
502enum btrfs_map_op {
503 BTRFS_MAP_READ,
504 BTRFS_MAP_WRITE,
505 BTRFS_MAP_DISCARD,
506 BTRFS_MAP_GET_READ_MIRRORS,
507};
508
509static inline enum btrfs_map_op btrfs_op(struct bio *bio)
510{
511 switch (bio_op(bio)) {
512 case REQ_OP_DISCARD:
513 return BTRFS_MAP_DISCARD;
514 case REQ_OP_WRITE:
515 case REQ_OP_ZONE_APPEND:
516 return BTRFS_MAP_WRITE;
517 default:
518 WARN_ON_ONCE(1);
519 fallthrough;
520 case REQ_OP_READ:
521 return BTRFS_MAP_READ;
522 }
523}
524
525static inline unsigned long btrfs_chunk_item_size(int num_stripes)
526{
527 ASSERT(num_stripes);
528 return sizeof(struct btrfs_chunk) +
529 sizeof(struct btrfs_stripe) * (num_stripes - 1);
530}
531
532void btrfs_get_bioc(struct btrfs_io_context *bioc);
533void btrfs_put_bioc(struct btrfs_io_context *bioc);
534int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
535 u64 logical, u64 *length,
536 struct btrfs_io_context **bioc_ret, int mirror_num);
537int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
538 u64 logical, u64 *length,
539 struct btrfs_io_context **bioc_ret);
540int __btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
541 u64 logical, u64 *length,
542 struct btrfs_io_context **bioc_ret,
543 struct btrfs_io_stripe *smap, int *mirror_num_ret,
544 int need_raid_map);
545struct btrfs_discard_stripe *btrfs_map_discard(struct btrfs_fs_info *fs_info,
546 u64 logical, u64 *length_ret,
547 u32 *num_stripes);
548int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, struct extent_map *map,
549 enum btrfs_map_op op, u64 logical,
550 struct btrfs_io_geometry *io_geom);
551int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
552int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
553struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans,
554 u64 type);
555void btrfs_mapping_tree_free(struct extent_map_tree *tree);
556int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
557 fmode_t flags, void *holder);
558struct btrfs_device *btrfs_scan_one_device(const char *path,
559 fmode_t flags, void *holder);
560int btrfs_forget_devices(dev_t devt);
561void btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
562void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices);
563void btrfs_assign_next_active_device(struct btrfs_device *device,
564 struct btrfs_device *this_dev);
565struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
566 u64 devid,
567 const char *devpath);
568int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
569 struct btrfs_dev_lookup_args *args,
570 const char *path);
571struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
572 const u64 *devid, const u8 *uuid,
573 const char *path);
574void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args);
575void btrfs_free_device(struct btrfs_device *device);
576int btrfs_rm_device(struct btrfs_fs_info *fs_info,
577 struct btrfs_dev_lookup_args *args,
578 struct block_device **bdev, fmode_t *mode);
579void __exit btrfs_cleanup_fs_uuids(void);
580int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
581int btrfs_grow_device(struct btrfs_trans_handle *trans,
582 struct btrfs_device *device, u64 new_size);
583struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices,
584 const struct btrfs_dev_lookup_args *args);
585int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
586int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
587int btrfs_balance(struct btrfs_fs_info *fs_info,
588 struct btrfs_balance_control *bctl,
589 struct btrfs_ioctl_balance_args *bargs);
590void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
591int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
592int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
593int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
594int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset);
595int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
596int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
597int btrfs_uuid_scan_kthread(void *data);
598bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset);
599int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
600 u64 *start, u64 *max_avail);
601void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
602int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
603 struct btrfs_ioctl_get_dev_stats *stats);
604int btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
605int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
606int btrfs_run_dev_stats(struct btrfs_trans_handle *trans);
607void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);
608void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);
609void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);
610int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
611 u64 logical, u64 len);
612unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
613 u64 logical);
614u64 btrfs_calc_stripe_length(const struct extent_map *em);
615int btrfs_nr_parity_stripes(u64 type);
616int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans,
617 struct btrfs_block_group *bg);
618int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);
619struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
620 u64 logical, u64 length);
621void btrfs_release_disk_super(struct btrfs_super_block *super);
622
623static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
624 int index)
625{
626 atomic_inc(dev->dev_stat_values + index);
627 /*
628 * This memory barrier orders stores updating statistics before stores
629 * updating dev_stats_ccnt.
630 *
631 * It pairs with smp_rmb() in btrfs_run_dev_stats().
632 */
633 smp_mb__before_atomic();
634 atomic_inc(&dev->dev_stats_ccnt);
635}
636
637static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
638 int index)
639{
640 return atomic_read(dev->dev_stat_values + index);
641}
642
643static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
644 int index)
645{
646 int ret;
647
648 ret = atomic_xchg(dev->dev_stat_values + index, 0);
649 /*
650 * atomic_xchg implies a full memory barriers as per atomic_t.txt:
651 * - RMW operations that have a return value are fully ordered;
652 *
653 * This implicit memory barriers is paired with the smp_rmb in
654 * btrfs_run_dev_stats
655 */
656 atomic_inc(&dev->dev_stats_ccnt);
657 return ret;
658}
659
660static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
661 int index, unsigned long val)
662{
663 atomic_set(dev->dev_stat_values + index, val);
664 /*
665 * This memory barrier orders stores updating statistics before stores
666 * updating dev_stats_ccnt.
667 *
668 * It pairs with smp_rmb() in btrfs_run_dev_stats().
669 */
670 smp_mb__before_atomic();
671 atomic_inc(&dev->dev_stats_ccnt);
672}
673
674static inline const char *btrfs_dev_name(const struct btrfs_device *device)
675{
676 if (!device || test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state))
677 return "<missing disk>";
678 else
679 return rcu_str_deref(device->name);
680}
681
682void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
683
684struct list_head * __attribute_const__ btrfs_get_fs_uuids(void);
685bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
686 struct btrfs_device *failing_dev);
687void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info,
688 struct block_device *bdev,
689 const char *device_path);
690
691enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags);
692int btrfs_bg_type_to_factor(u64 flags);
693const char *btrfs_bg_type_to_raid_name(u64 flags);
694int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
695bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical);
696
697bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr);
698
699#endif
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
16extern struct mutex uuid_mutex;
17
18#define BTRFS_STRIPE_LEN SZ_64K
19
20struct 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
54struct btrfs_device {
55 struct list_head dev_list; /* device_list_mutex */
56 struct list_head dev_alloc_list; /* chunk mutex */
57 struct list_head post_commit_list; /* chunk mutex */
58 struct btrfs_fs_devices *fs_devices;
59 struct btrfs_fs_info *fs_info;
60
61 struct rcu_string *name;
62
63 u64 generation;
64
65 struct block_device *bdev;
66
67 /* the mode sent to blkdev_get */
68 fmode_t mode;
69
70 unsigned long dev_state;
71 blk_status_t last_flush_error;
72
73#ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
74 seqcount_t data_seqcount;
75#endif
76
77 /* the internal btrfs device id */
78 u64 devid;
79
80 /* size of the device in memory */
81 u64 total_bytes;
82
83 /* size of the device on disk */
84 u64 disk_total_bytes;
85
86 /* bytes used */
87 u64 bytes_used;
88
89 /* optimal io alignment for this device */
90 u32 io_align;
91
92 /* optimal io width for this device */
93 u32 io_width;
94 /* type and info about this device */
95 u64 type;
96
97 /* minimal io size for this device */
98 u32 sector_size;
99
100 /* physical drive uuid (or lvm uuid) */
101 u8 uuid[BTRFS_UUID_SIZE];
102
103 /*
104 * size of the device on the current transaction
105 *
106 * This variant is update when committing the transaction,
107 * and protected by chunk mutex
108 */
109 u64 commit_total_bytes;
110
111 /* bytes used on the current transaction */
112 u64 commit_bytes_used;
113
114 /* for sending down flush barriers */
115 struct bio *flush_bio;
116 struct completion flush_wait;
117
118 /* per-device scrub information */
119 struct scrub_ctx *scrub_ctx;
120
121 /* readahead state */
122 atomic_t reada_in_flight;
123 u64 reada_next;
124 struct reada_zone *reada_curr_zone;
125 struct radix_tree_root reada_zones;
126 struct radix_tree_root reada_extents;
127
128 /* disk I/O failure stats. For detailed description refer to
129 * enum btrfs_dev_stat_values in ioctl.h */
130 int dev_stats_valid;
131
132 /* Counter to record the change of device stats */
133 atomic_t dev_stats_ccnt;
134 atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
135
136 struct extent_io_tree alloc_state;
137
138 struct completion kobj_unregister;
139 /* For sysfs/FSID/devinfo/devid/ */
140 struct kobject devid_kobj;
141};
142
143/*
144 * If we read those variants at the context of their own lock, we needn't
145 * use the following helpers, reading them directly is safe.
146 */
147#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
148#define BTRFS_DEVICE_GETSET_FUNCS(name) \
149static inline u64 \
150btrfs_device_get_##name(const struct btrfs_device *dev) \
151{ \
152 u64 size; \
153 unsigned int seq; \
154 \
155 do { \
156 seq = read_seqcount_begin(&dev->data_seqcount); \
157 size = dev->name; \
158 } while (read_seqcount_retry(&dev->data_seqcount, seq)); \
159 return size; \
160} \
161 \
162static inline void \
163btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
164{ \
165 preempt_disable(); \
166 write_seqcount_begin(&dev->data_seqcount); \
167 dev->name = size; \
168 write_seqcount_end(&dev->data_seqcount); \
169 preempt_enable(); \
170}
171#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
172#define BTRFS_DEVICE_GETSET_FUNCS(name) \
173static inline u64 \
174btrfs_device_get_##name(const struct btrfs_device *dev) \
175{ \
176 u64 size; \
177 \
178 preempt_disable(); \
179 size = dev->name; \
180 preempt_enable(); \
181 return size; \
182} \
183 \
184static inline void \
185btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
186{ \
187 preempt_disable(); \
188 dev->name = size; \
189 preempt_enable(); \
190}
191#else
192#define BTRFS_DEVICE_GETSET_FUNCS(name) \
193static inline u64 \
194btrfs_device_get_##name(const struct btrfs_device *dev) \
195{ \
196 return dev->name; \
197} \
198 \
199static inline void \
200btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
201{ \
202 dev->name = size; \
203}
204#endif
205
206BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
207BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
208BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
209
210enum btrfs_chunk_allocation_policy {
211 BTRFS_CHUNK_ALLOC_REGULAR,
212};
213
214struct btrfs_fs_devices {
215 u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
216 u8 metadata_uuid[BTRFS_FSID_SIZE];
217 bool fsid_change;
218 struct list_head fs_list;
219
220 u64 num_devices;
221 u64 open_devices;
222 u64 rw_devices;
223 u64 missing_devices;
224 u64 total_rw_bytes;
225 u64 total_devices;
226
227 /* Highest generation number of seen devices */
228 u64 latest_generation;
229
230 struct block_device *latest_bdev;
231
232 /* all of the devices in the FS, protected by a mutex
233 * so we can safely walk it to write out the supers without
234 * worrying about add/remove by the multi-device code.
235 * Scrubbing super can kick off supers writing by holding
236 * this mutex lock.
237 */
238 struct mutex device_list_mutex;
239
240 /* List of all devices, protected by device_list_mutex */
241 struct list_head devices;
242
243 /*
244 * Devices which can satisfy space allocation. Protected by
245 * chunk_mutex
246 */
247 struct list_head alloc_list;
248
249 struct btrfs_fs_devices *seed;
250 bool seeding;
251
252 int opened;
253
254 /* set when we find or add a device that doesn't have the
255 * nonrot flag set
256 */
257 bool rotating;
258
259 struct btrfs_fs_info *fs_info;
260 /* sysfs kobjects */
261 struct kobject fsid_kobj;
262 struct kobject *devices_kobj;
263 struct kobject *devinfo_kobj;
264 struct completion kobj_unregister;
265
266 enum btrfs_chunk_allocation_policy chunk_alloc_policy;
267};
268
269#define BTRFS_BIO_INLINE_CSUM_SIZE 64
270
271#define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info) \
272 - sizeof(struct btrfs_chunk)) \
273 / sizeof(struct btrfs_stripe) + 1)
274
275#define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE \
276 - 2 * sizeof(struct btrfs_disk_key) \
277 - 2 * sizeof(struct btrfs_chunk)) \
278 / sizeof(struct btrfs_stripe) + 1)
279
280/*
281 * we need the mirror number and stripe index to be passed around
282 * the call chain while we are processing end_io (especially errors).
283 * Really, what we need is a btrfs_bio structure that has this info
284 * and is properly sized with its stripe array, but we're not there
285 * quite yet. We have our own btrfs bioset, and all of the bios
286 * we allocate are actually btrfs_io_bios. We'll cram as much of
287 * struct btrfs_bio as we can into this over time.
288 */
289struct btrfs_io_bio {
290 unsigned int mirror_num;
291 struct btrfs_device *device;
292 u64 logical;
293 u8 *csum;
294 u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
295 struct bvec_iter iter;
296 /*
297 * This member must come last, bio_alloc_bioset will allocate enough
298 * bytes for entire btrfs_io_bio but relies on bio being last.
299 */
300 struct bio bio;
301};
302
303static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
304{
305 return container_of(bio, struct btrfs_io_bio, bio);
306}
307
308static inline void btrfs_io_bio_free_csum(struct btrfs_io_bio *io_bio)
309{
310 if (io_bio->csum != io_bio->csum_inline) {
311 kfree(io_bio->csum);
312 io_bio->csum = NULL;
313 }
314}
315
316struct btrfs_bio_stripe {
317 struct btrfs_device *dev;
318 u64 physical;
319 u64 length; /* only used for discard mappings */
320};
321
322struct btrfs_bio {
323 refcount_t refs;
324 atomic_t stripes_pending;
325 struct btrfs_fs_info *fs_info;
326 u64 map_type; /* get from map_lookup->type */
327 bio_end_io_t *end_io;
328 struct bio *orig_bio;
329 void *private;
330 atomic_t error;
331 int max_errors;
332 int num_stripes;
333 int mirror_num;
334 int num_tgtdevs;
335 int *tgtdev_map;
336 /*
337 * logical block numbers for the start of each stripe
338 * The last one or two are p/q. These are sorted,
339 * so raid_map[0] is the start of our full stripe
340 */
341 u64 *raid_map;
342 struct btrfs_bio_stripe stripes[];
343};
344
345struct btrfs_device_info {
346 struct btrfs_device *dev;
347 u64 dev_offset;
348 u64 max_avail;
349 u64 total_avail;
350};
351
352struct btrfs_raid_attr {
353 u8 sub_stripes; /* sub_stripes info for map */
354 u8 dev_stripes; /* stripes per dev */
355 u8 devs_max; /* max devs to use */
356 u8 devs_min; /* min devs needed */
357 u8 tolerated_failures; /* max tolerated fail devs */
358 u8 devs_increment; /* ndevs has to be a multiple of this */
359 u8 ncopies; /* how many copies to data has */
360 u8 nparity; /* number of stripes worth of bytes to store
361 * parity information */
362 u8 mindev_error; /* error code if min devs requisite is unmet */
363 const char raid_name[8]; /* name of the raid */
364 u64 bg_flag; /* block group flag of the raid */
365};
366
367extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
368
369struct map_lookup {
370 u64 type;
371 int io_align;
372 int io_width;
373 u64 stripe_len;
374 int num_stripes;
375 int sub_stripes;
376 int verified_stripes; /* For mount time dev extent verification */
377 struct btrfs_bio_stripe stripes[];
378};
379
380#define map_lookup_size(n) (sizeof(struct map_lookup) + \
381 (sizeof(struct btrfs_bio_stripe) * (n)))
382
383struct btrfs_balance_args;
384struct btrfs_balance_progress;
385struct btrfs_balance_control {
386 struct btrfs_balance_args data;
387 struct btrfs_balance_args meta;
388 struct btrfs_balance_args sys;
389
390 u64 flags;
391
392 struct btrfs_balance_progress stat;
393};
394
395enum btrfs_map_op {
396 BTRFS_MAP_READ,
397 BTRFS_MAP_WRITE,
398 BTRFS_MAP_DISCARD,
399 BTRFS_MAP_GET_READ_MIRRORS,
400};
401
402static inline enum btrfs_map_op btrfs_op(struct bio *bio)
403{
404 switch (bio_op(bio)) {
405 case REQ_OP_DISCARD:
406 return BTRFS_MAP_DISCARD;
407 case REQ_OP_WRITE:
408 return BTRFS_MAP_WRITE;
409 default:
410 WARN_ON_ONCE(1);
411 fallthrough;
412 case REQ_OP_READ:
413 return BTRFS_MAP_READ;
414 }
415}
416
417void btrfs_get_bbio(struct btrfs_bio *bbio);
418void btrfs_put_bbio(struct btrfs_bio *bbio);
419int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
420 u64 logical, u64 *length,
421 struct btrfs_bio **bbio_ret, int mirror_num);
422int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
423 u64 logical, u64 *length,
424 struct btrfs_bio **bbio_ret);
425int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
426 u64 logical, u64 len, struct btrfs_io_geometry *io_geom);
427int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
428int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
429int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, u64 type);
430void btrfs_mapping_tree_free(struct extent_map_tree *tree);
431blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
432 int mirror_num);
433int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
434 fmode_t flags, void *holder);
435struct btrfs_device *btrfs_scan_one_device(const char *path,
436 fmode_t flags, void *holder);
437int btrfs_forget_devices(const char *path);
438int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
439void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices, int step);
440void btrfs_assign_next_active_device(struct btrfs_device *device,
441 struct btrfs_device *this_dev);
442struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
443 u64 devid,
444 const char *devpath);
445struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
446 const u64 *devid,
447 const u8 *uuid);
448void btrfs_free_device(struct btrfs_device *device);
449int btrfs_rm_device(struct btrfs_fs_info *fs_info,
450 const char *device_path, u64 devid);
451void __exit btrfs_cleanup_fs_uuids(void);
452int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
453int btrfs_grow_device(struct btrfs_trans_handle *trans,
454 struct btrfs_device *device, u64 new_size);
455struct btrfs_device *btrfs_find_device(struct btrfs_fs_devices *fs_devices,
456 u64 devid, u8 *uuid, u8 *fsid, bool seed);
457int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
458int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
459int btrfs_balance(struct btrfs_fs_info *fs_info,
460 struct btrfs_balance_control *bctl,
461 struct btrfs_ioctl_balance_args *bargs);
462void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
463int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
464int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
465int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
466int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
467int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
468int btrfs_uuid_scan_kthread(void *data);
469int btrfs_chunk_readonly(struct btrfs_fs_info *fs_info, u64 chunk_offset);
470int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
471 u64 *start, u64 *max_avail);
472void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
473int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
474 struct btrfs_ioctl_get_dev_stats *stats);
475void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
476int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
477int btrfs_run_dev_stats(struct btrfs_trans_handle *trans);
478void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);
479void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);
480void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);
481int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
482 u64 logical, u64 len);
483unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
484 u64 logical);
485int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
486 u64 chunk_offset, u64 chunk_size);
487int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);
488struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
489 u64 logical, u64 length);
490void btrfs_release_disk_super(struct btrfs_super_block *super);
491
492static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
493 int index)
494{
495 atomic_inc(dev->dev_stat_values + index);
496 /*
497 * This memory barrier orders stores updating statistics before stores
498 * updating dev_stats_ccnt.
499 *
500 * It pairs with smp_rmb() in btrfs_run_dev_stats().
501 */
502 smp_mb__before_atomic();
503 atomic_inc(&dev->dev_stats_ccnt);
504}
505
506static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
507 int index)
508{
509 return atomic_read(dev->dev_stat_values + index);
510}
511
512static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
513 int index)
514{
515 int ret;
516
517 ret = atomic_xchg(dev->dev_stat_values + index, 0);
518 /*
519 * atomic_xchg implies a full memory barriers as per atomic_t.txt:
520 * - RMW operations that have a return value are fully ordered;
521 *
522 * This implicit memory barriers is paired with the smp_rmb in
523 * btrfs_run_dev_stats
524 */
525 atomic_inc(&dev->dev_stats_ccnt);
526 return ret;
527}
528
529static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
530 int index, unsigned long val)
531{
532 atomic_set(dev->dev_stat_values + index, val);
533 /*
534 * This memory barrier orders stores updating statistics before stores
535 * updating dev_stats_ccnt.
536 *
537 * It pairs with smp_rmb() in btrfs_run_dev_stats().
538 */
539 smp_mb__before_atomic();
540 atomic_inc(&dev->dev_stats_ccnt);
541}
542
543/*
544 * Convert block group flags (BTRFS_BLOCK_GROUP_*) to btrfs_raid_types, which
545 * can be used as index to access btrfs_raid_array[].
546 */
547static inline enum btrfs_raid_types btrfs_bg_flags_to_raid_index(u64 flags)
548{
549 if (flags & BTRFS_BLOCK_GROUP_RAID10)
550 return BTRFS_RAID_RAID10;
551 else if (flags & BTRFS_BLOCK_GROUP_RAID1)
552 return BTRFS_RAID_RAID1;
553 else if (flags & BTRFS_BLOCK_GROUP_RAID1C3)
554 return BTRFS_RAID_RAID1C3;
555 else if (flags & BTRFS_BLOCK_GROUP_RAID1C4)
556 return BTRFS_RAID_RAID1C4;
557 else if (flags & BTRFS_BLOCK_GROUP_DUP)
558 return BTRFS_RAID_DUP;
559 else if (flags & BTRFS_BLOCK_GROUP_RAID0)
560 return BTRFS_RAID_RAID0;
561 else if (flags & BTRFS_BLOCK_GROUP_RAID5)
562 return BTRFS_RAID_RAID5;
563 else if (flags & BTRFS_BLOCK_GROUP_RAID6)
564 return BTRFS_RAID_RAID6;
565
566 return BTRFS_RAID_SINGLE; /* BTRFS_BLOCK_GROUP_SINGLE */
567}
568
569void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
570
571struct list_head * __attribute_const__ btrfs_get_fs_uuids(void);
572void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info);
573void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info);
574bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
575 struct btrfs_device *failing_dev);
576void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info,
577 struct block_device *bdev,
578 const char *device_path);
579
580int btrfs_bg_type_to_factor(u64 flags);
581const char *btrfs_bg_type_to_raid_name(u64 flags);
582int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
583
584#endif