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1/*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19#ifndef __BTRFS_VOLUMES_
20#define __BTRFS_VOLUMES_
21
22#include <linux/bio.h>
23#include <linux/sort.h>
24#include <linux/btrfs.h>
25#include "async-thread.h"
26
27extern struct mutex uuid_mutex;
28
29#define BTRFS_STRIPE_LEN SZ_64K
30
31struct buffer_head;
32struct btrfs_pending_bios {
33 struct bio *head;
34 struct bio *tail;
35};
36
37/*
38 * Use sequence counter to get consistent device stat data on
39 * 32-bit processors.
40 */
41#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
42#include <linux/seqlock.h>
43#define __BTRFS_NEED_DEVICE_DATA_ORDERED
44#define btrfs_device_data_ordered_init(device) \
45 seqcount_init(&device->data_seqcount)
46#else
47#define btrfs_device_data_ordered_init(device) do { } while (0)
48#endif
49
50struct btrfs_device {
51 struct list_head dev_list;
52 struct list_head dev_alloc_list;
53 struct btrfs_fs_devices *fs_devices;
54 struct btrfs_fs_info *fs_info;
55
56 struct rcu_string *name;
57
58 u64 generation;
59
60 spinlock_t io_lock ____cacheline_aligned;
61 int running_pending;
62 /* regular prio bios */
63 struct btrfs_pending_bios pending_bios;
64 /* sync bios */
65 struct btrfs_pending_bios pending_sync_bios;
66
67 struct block_device *bdev;
68
69 /* the mode sent to blkdev_get */
70 fmode_t mode;
71
72 int writeable;
73 int in_fs_metadata;
74 int missing;
75 int can_discard;
76 int is_tgtdev_for_dev_replace;
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 device_list_mutex
113 */
114 u64 commit_total_bytes;
115
116 /* bytes used on the current transaction */
117 u64 commit_bytes_used;
118 /*
119 * used to manage the device which is resized
120 *
121 * It is protected by chunk_lock.
122 */
123 struct list_head resized_list;
124
125 /* for sending down flush barriers */
126 int nobarriers;
127 struct bio *flush_bio;
128 struct completion flush_wait;
129
130 /* per-device scrub information */
131 struct scrub_ctx *scrub_device;
132
133 struct btrfs_work work;
134 struct rcu_head rcu;
135 struct work_struct rcu_work;
136
137 /* readahead state */
138 spinlock_t reada_lock;
139 atomic_t reada_in_flight;
140 u64 reada_next;
141 struct reada_zone *reada_curr_zone;
142 struct radix_tree_root reada_zones;
143 struct radix_tree_root reada_extents;
144
145 /* disk I/O failure stats. For detailed description refer to
146 * enum btrfs_dev_stat_values in ioctl.h */
147 int dev_stats_valid;
148
149 /* Counter to record the change of device stats */
150 atomic_t dev_stats_ccnt;
151 atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
152};
153
154/*
155 * If we read those variants at the context of their own lock, we needn't
156 * use the following helpers, reading them directly is safe.
157 */
158#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
159#define BTRFS_DEVICE_GETSET_FUNCS(name) \
160static inline u64 \
161btrfs_device_get_##name(const struct btrfs_device *dev) \
162{ \
163 u64 size; \
164 unsigned int seq; \
165 \
166 do { \
167 seq = read_seqcount_begin(&dev->data_seqcount); \
168 size = dev->name; \
169 } while (read_seqcount_retry(&dev->data_seqcount, seq)); \
170 return size; \
171} \
172 \
173static inline void \
174btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
175{ \
176 preempt_disable(); \
177 write_seqcount_begin(&dev->data_seqcount); \
178 dev->name = size; \
179 write_seqcount_end(&dev->data_seqcount); \
180 preempt_enable(); \
181}
182#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
183#define BTRFS_DEVICE_GETSET_FUNCS(name) \
184static inline u64 \
185btrfs_device_get_##name(const struct btrfs_device *dev) \
186{ \
187 u64 size; \
188 \
189 preempt_disable(); \
190 size = dev->name; \
191 preempt_enable(); \
192 return size; \
193} \
194 \
195static inline void \
196btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
197{ \
198 preempt_disable(); \
199 dev->name = size; \
200 preempt_enable(); \
201}
202#else
203#define BTRFS_DEVICE_GETSET_FUNCS(name) \
204static inline u64 \
205btrfs_device_get_##name(const struct btrfs_device *dev) \
206{ \
207 return dev->name; \
208} \
209 \
210static inline void \
211btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
212{ \
213 dev->name = size; \
214}
215#endif
216
217BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
218BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
219BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
220
221struct btrfs_fs_devices {
222 u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
223
224 u64 num_devices;
225 u64 open_devices;
226 u64 rw_devices;
227 u64 missing_devices;
228 u64 total_rw_bytes;
229 u64 total_devices;
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 struct list_head devices;
240
241 struct list_head resized_devices;
242 /* devices not currently being allocated */
243 struct list_head alloc_list;
244 struct list_head list;
245
246 struct btrfs_fs_devices *seed;
247 int seeding;
248
249 int opened;
250
251 /* set when we find or add a device that doesn't have the
252 * nonrot flag set
253 */
254 int rotating;
255
256 struct btrfs_fs_info *fs_info;
257 /* sysfs kobjects */
258 struct kobject fsid_kobj;
259 struct kobject *device_dir_kobj;
260 struct completion kobj_unregister;
261};
262
263#define BTRFS_BIO_INLINE_CSUM_SIZE 64
264
265/*
266 * we need the mirror number and stripe index to be passed around
267 * the call chain while we are processing end_io (especially errors).
268 * Really, what we need is a btrfs_bio structure that has this info
269 * and is properly sized with its stripe array, but we're not there
270 * quite yet. We have our own btrfs bioset, and all of the bios
271 * we allocate are actually btrfs_io_bios. We'll cram as much of
272 * struct btrfs_bio as we can into this over time.
273 */
274typedef void (btrfs_io_bio_end_io_t) (struct btrfs_io_bio *bio, int err);
275struct btrfs_io_bio {
276 unsigned int mirror_num;
277 unsigned int stripe_index;
278 u64 logical;
279 u8 *csum;
280 u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
281 u8 *csum_allocated;
282 btrfs_io_bio_end_io_t *end_io;
283 struct bio bio;
284};
285
286static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
287{
288 return container_of(bio, struct btrfs_io_bio, bio);
289}
290
291struct btrfs_bio_stripe {
292 struct btrfs_device *dev;
293 u64 physical;
294 u64 length; /* only used for discard mappings */
295};
296
297struct btrfs_bio;
298typedef void (btrfs_bio_end_io_t) (struct btrfs_bio *bio, int err);
299
300struct btrfs_bio {
301 atomic_t refs;
302 atomic_t stripes_pending;
303 struct btrfs_fs_info *fs_info;
304 u64 map_type; /* get from map_lookup->type */
305 bio_end_io_t *end_io;
306 struct bio *orig_bio;
307 unsigned long flags;
308 void *private;
309 atomic_t error;
310 int max_errors;
311 int num_stripes;
312 int mirror_num;
313 int num_tgtdevs;
314 int *tgtdev_map;
315 /*
316 * logical block numbers for the start of each stripe
317 * The last one or two are p/q. These are sorted,
318 * so raid_map[0] is the start of our full stripe
319 */
320 u64 *raid_map;
321 struct btrfs_bio_stripe stripes[];
322};
323
324struct btrfs_device_info {
325 struct btrfs_device *dev;
326 u64 dev_offset;
327 u64 max_avail;
328 u64 total_avail;
329};
330
331struct btrfs_raid_attr {
332 int sub_stripes; /* sub_stripes info for map */
333 int dev_stripes; /* stripes per dev */
334 int devs_max; /* max devs to use */
335 int devs_min; /* min devs needed */
336 int tolerated_failures; /* max tolerated fail devs */
337 int devs_increment; /* ndevs has to be a multiple of this */
338 int ncopies; /* how many copies to data has */
339};
340
341extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
342extern const int btrfs_raid_mindev_error[BTRFS_NR_RAID_TYPES];
343extern const u64 btrfs_raid_group[BTRFS_NR_RAID_TYPES];
344
345struct map_lookup {
346 u64 type;
347 int io_align;
348 int io_width;
349 u64 stripe_len;
350 int sector_size;
351 int num_stripes;
352 int sub_stripes;
353 struct btrfs_bio_stripe stripes[];
354};
355
356#define map_lookup_size(n) (sizeof(struct map_lookup) + \
357 (sizeof(struct btrfs_bio_stripe) * (n)))
358
359struct btrfs_balance_args;
360struct btrfs_balance_progress;
361struct btrfs_balance_control {
362 struct btrfs_fs_info *fs_info;
363
364 struct btrfs_balance_args data;
365 struct btrfs_balance_args meta;
366 struct btrfs_balance_args sys;
367
368 u64 flags;
369
370 struct btrfs_balance_progress stat;
371};
372
373enum btrfs_map_op {
374 BTRFS_MAP_READ,
375 BTRFS_MAP_WRITE,
376 BTRFS_MAP_DISCARD,
377 BTRFS_MAP_GET_READ_MIRRORS,
378};
379
380static inline enum btrfs_map_op btrfs_op(struct bio *bio)
381{
382 switch (bio_op(bio)) {
383 case REQ_OP_DISCARD:
384 return BTRFS_MAP_DISCARD;
385 case REQ_OP_WRITE:
386 return BTRFS_MAP_WRITE;
387 default:
388 WARN_ON_ONCE(1);
389 case REQ_OP_READ:
390 return BTRFS_MAP_READ;
391 }
392}
393
394int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
395 u64 end, u64 *length);
396void btrfs_get_bbio(struct btrfs_bio *bbio);
397void btrfs_put_bbio(struct btrfs_bio *bbio);
398int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
399 u64 logical, u64 *length,
400 struct btrfs_bio **bbio_ret, int mirror_num);
401int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
402 u64 logical, u64 *length,
403 struct btrfs_bio **bbio_ret, int mirror_num,
404 int need_raid_map);
405int btrfs_rmap_block(struct btrfs_fs_info *fs_info,
406 u64 chunk_start, u64 physical, u64 devid,
407 u64 **logical, int *naddrs, int *stripe_len);
408int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
409int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
410int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
411 struct btrfs_fs_info *fs_info, u64 type);
412void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
413void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
414int btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
415 int mirror_num, int async_submit);
416int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
417 fmode_t flags, void *holder);
418int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
419 struct btrfs_fs_devices **fs_devices_ret);
420int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
421void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices, int step);
422void btrfs_assign_next_active_device(struct btrfs_fs_info *fs_info,
423 struct btrfs_device *device, struct btrfs_device *this_dev);
424int btrfs_find_device_missing_or_by_path(struct btrfs_fs_info *fs_info,
425 char *device_path,
426 struct btrfs_device **device);
427int btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info, u64 devid,
428 char *devpath,
429 struct btrfs_device **device);
430struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
431 const u64 *devid,
432 const u8 *uuid);
433int btrfs_rm_device(struct btrfs_fs_info *fs_info,
434 char *device_path, u64 devid);
435void btrfs_cleanup_fs_uuids(void);
436int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
437int btrfs_grow_device(struct btrfs_trans_handle *trans,
438 struct btrfs_device *device, u64 new_size);
439struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
440 u8 *uuid, u8 *fsid);
441int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
442int btrfs_init_new_device(struct btrfs_fs_info *fs_info, char *path);
443int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
444 char *device_path,
445 struct btrfs_device *srcdev,
446 struct btrfs_device **device_out);
447int btrfs_balance(struct btrfs_balance_control *bctl,
448 struct btrfs_ioctl_balance_args *bargs);
449int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
450int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
451int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
452int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
453int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
454int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info);
455int btrfs_chunk_readonly(struct btrfs_fs_info *fs_info, u64 chunk_offset);
456int find_free_dev_extent_start(struct btrfs_transaction *transaction,
457 struct btrfs_device *device, u64 num_bytes,
458 u64 search_start, u64 *start, u64 *max_avail);
459int find_free_dev_extent(struct btrfs_trans_handle *trans,
460 struct btrfs_device *device, u64 num_bytes,
461 u64 *start, u64 *max_avail);
462void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
463int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
464 struct btrfs_ioctl_get_dev_stats *stats);
465void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
466int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
467int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
468 struct btrfs_fs_info *fs_info);
469void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
470 struct btrfs_device *srcdev);
471void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
472 struct btrfs_device *srcdev);
473void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
474 struct btrfs_device *tgtdev);
475void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
476 struct btrfs_device *tgtdev);
477void btrfs_scratch_superblocks(struct block_device *bdev, char *device_path);
478int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
479 u64 logical, u64 len, int mirror_num);
480unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
481 struct btrfs_mapping_tree *map_tree,
482 u64 logical);
483int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
484 struct btrfs_fs_info *fs_info,
485 u64 chunk_offset, u64 chunk_size);
486int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
487 struct btrfs_fs_info *fs_info, u64 chunk_offset);
488
489static inline int btrfs_dev_stats_dirty(struct btrfs_device *dev)
490{
491 return atomic_read(&dev->dev_stats_ccnt);
492}
493
494static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
495 int index)
496{
497 atomic_inc(dev->dev_stat_values + index);
498 smp_mb__before_atomic();
499 atomic_inc(&dev->dev_stats_ccnt);
500}
501
502static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
503 int index)
504{
505 return atomic_read(dev->dev_stat_values + index);
506}
507
508static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
509 int index)
510{
511 int ret;
512
513 ret = atomic_xchg(dev->dev_stat_values + index, 0);
514 smp_mb__before_atomic();
515 atomic_inc(&dev->dev_stats_ccnt);
516 return ret;
517}
518
519static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
520 int index, unsigned long val)
521{
522 atomic_set(dev->dev_stat_values + index, val);
523 smp_mb__before_atomic();
524 atomic_inc(&dev->dev_stats_ccnt);
525}
526
527static inline void btrfs_dev_stat_reset(struct btrfs_device *dev,
528 int index)
529{
530 btrfs_dev_stat_set(dev, index, 0);
531}
532
533void btrfs_update_commit_device_size(struct btrfs_fs_info *fs_info);
534void btrfs_update_commit_device_bytes_used(struct btrfs_fs_info *fs_info,
535 struct btrfs_transaction *transaction);
536
537struct list_head *btrfs_get_fs_uuids(void);
538void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info);
539void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info);
540
541#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/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#define BTRFS_STRIPE_LEN_SHIFT (16)
22#define BTRFS_STRIPE_LEN_MASK (BTRFS_STRIPE_LEN - 1)
23
24static_assert(const_ilog2(BTRFS_STRIPE_LEN) == BTRFS_STRIPE_LEN_SHIFT);
25
26/* Used by sanity check for btrfs_raid_types. */
27#define const_ffs(n) (__builtin_ctzll(n) + 1)
28
29/*
30 * The conversion from BTRFS_BLOCK_GROUP_* bits to btrfs_raid_type requires
31 * RAID0 always to be the lowest profile bit.
32 * Although it's part of on-disk format and should never change, do extra
33 * compile-time sanity checks.
34 */
35static_assert(const_ffs(BTRFS_BLOCK_GROUP_RAID0) <
36 const_ffs(BTRFS_BLOCK_GROUP_PROFILE_MASK & ~BTRFS_BLOCK_GROUP_RAID0));
37static_assert(const_ilog2(BTRFS_BLOCK_GROUP_RAID0) >
38 ilog2(BTRFS_BLOCK_GROUP_TYPE_MASK));
39
40/* ilog2() can handle both constants and variables */
41#define BTRFS_BG_FLAG_TO_INDEX(profile) \
42 ilog2((profile) >> (ilog2(BTRFS_BLOCK_GROUP_RAID0) - 1))
43
44enum btrfs_raid_types {
45 /* SINGLE is the special one as it doesn't have on-disk bit. */
46 BTRFS_RAID_SINGLE = 0,
47
48 BTRFS_RAID_RAID0 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID0),
49 BTRFS_RAID_RAID1 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1),
50 BTRFS_RAID_DUP = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_DUP),
51 BTRFS_RAID_RAID10 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID10),
52 BTRFS_RAID_RAID5 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID5),
53 BTRFS_RAID_RAID6 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID6),
54 BTRFS_RAID_RAID1C3 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C3),
55 BTRFS_RAID_RAID1C4 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C4),
56
57 BTRFS_NR_RAID_TYPES
58};
59
60/*
61 * Use sequence counter to get consistent device stat data on
62 * 32-bit processors.
63 */
64#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
65#include <linux/seqlock.h>
66#define __BTRFS_NEED_DEVICE_DATA_ORDERED
67#define btrfs_device_data_ordered_init(device) \
68 seqcount_init(&device->data_seqcount)
69#else
70#define btrfs_device_data_ordered_init(device) do { } while (0)
71#endif
72
73#define BTRFS_DEV_STATE_WRITEABLE (0)
74#define BTRFS_DEV_STATE_IN_FS_METADATA (1)
75#define BTRFS_DEV_STATE_MISSING (2)
76#define BTRFS_DEV_STATE_REPLACE_TGT (3)
77#define BTRFS_DEV_STATE_FLUSH_SENT (4)
78#define BTRFS_DEV_STATE_NO_READA (5)
79
80struct btrfs_zoned_device_info;
81
82struct btrfs_device {
83 struct list_head dev_list; /* device_list_mutex */
84 struct list_head dev_alloc_list; /* chunk mutex */
85 struct list_head post_commit_list; /* chunk mutex */
86 struct btrfs_fs_devices *fs_devices;
87 struct btrfs_fs_info *fs_info;
88
89 struct rcu_string __rcu *name;
90
91 u64 generation;
92
93 struct bdev_handle *bdev_handle;
94 struct block_device *bdev;
95
96 struct btrfs_zoned_device_info *zone_info;
97
98 /*
99 * Device's major-minor number. Must be set even if the device is not
100 * opened (bdev == NULL), unless the device is missing.
101 */
102 dev_t devt;
103 unsigned long dev_state;
104 blk_status_t last_flush_error;
105
106#ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
107 seqcount_t data_seqcount;
108#endif
109
110 /* the internal btrfs device id */
111 u64 devid;
112
113 /* size of the device in memory */
114 u64 total_bytes;
115
116 /* size of the device on disk */
117 u64 disk_total_bytes;
118
119 /* bytes used */
120 u64 bytes_used;
121
122 /* optimal io alignment for this device */
123 u32 io_align;
124
125 /* optimal io width for this device */
126 u32 io_width;
127 /* type and info about this device */
128 u64 type;
129
130 /* minimal io size for this device */
131 u32 sector_size;
132
133 /* physical drive uuid (or lvm uuid) */
134 u8 uuid[BTRFS_UUID_SIZE];
135
136 /*
137 * size of the device on the current transaction
138 *
139 * This variant is update when committing the transaction,
140 * and protected by chunk mutex
141 */
142 u64 commit_total_bytes;
143
144 /* bytes used on the current transaction */
145 u64 commit_bytes_used;
146
147 /* Bio used for flushing device barriers */
148 struct bio flush_bio;
149 struct completion flush_wait;
150
151 /* per-device scrub information */
152 struct scrub_ctx *scrub_ctx;
153
154 /* disk I/O failure stats. For detailed description refer to
155 * enum btrfs_dev_stat_values in ioctl.h */
156 int dev_stats_valid;
157
158 /* Counter to record the change of device stats */
159 atomic_t dev_stats_ccnt;
160 atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
161
162 struct extent_io_tree alloc_state;
163
164 struct completion kobj_unregister;
165 /* For sysfs/FSID/devinfo/devid/ */
166 struct kobject devid_kobj;
167
168 /* Bandwidth limit for scrub, in bytes */
169 u64 scrub_speed_max;
170};
171
172/*
173 * Block group or device which contains an active swapfile. Used for preventing
174 * unsafe operations while a swapfile is active.
175 *
176 * These are sorted on (ptr, inode) (note that a block group or device can
177 * contain more than one swapfile). We compare the pointer values because we
178 * don't actually care what the object is, we just need a quick check whether
179 * the object exists in the rbtree.
180 */
181struct btrfs_swapfile_pin {
182 struct rb_node node;
183 void *ptr;
184 struct inode *inode;
185 /*
186 * If true, ptr points to a struct btrfs_block_group. Otherwise, ptr
187 * points to a struct btrfs_device.
188 */
189 bool is_block_group;
190 /*
191 * Only used when 'is_block_group' is true and it is the number of
192 * extents used by a swapfile for this block group ('ptr' field).
193 */
194 int bg_extent_count;
195};
196
197/*
198 * If we read those variants at the context of their own lock, we needn't
199 * use the following helpers, reading them directly is safe.
200 */
201#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
202#define BTRFS_DEVICE_GETSET_FUNCS(name) \
203static inline u64 \
204btrfs_device_get_##name(const struct btrfs_device *dev) \
205{ \
206 u64 size; \
207 unsigned int seq; \
208 \
209 do { \
210 seq = read_seqcount_begin(&dev->data_seqcount); \
211 size = dev->name; \
212 } while (read_seqcount_retry(&dev->data_seqcount, seq)); \
213 return size; \
214} \
215 \
216static inline void \
217btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
218{ \
219 preempt_disable(); \
220 write_seqcount_begin(&dev->data_seqcount); \
221 dev->name = size; \
222 write_seqcount_end(&dev->data_seqcount); \
223 preempt_enable(); \
224}
225#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
226#define BTRFS_DEVICE_GETSET_FUNCS(name) \
227static inline u64 \
228btrfs_device_get_##name(const struct btrfs_device *dev) \
229{ \
230 u64 size; \
231 \
232 preempt_disable(); \
233 size = dev->name; \
234 preempt_enable(); \
235 return size; \
236} \
237 \
238static inline void \
239btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
240{ \
241 preempt_disable(); \
242 dev->name = size; \
243 preempt_enable(); \
244}
245#else
246#define BTRFS_DEVICE_GETSET_FUNCS(name) \
247static inline u64 \
248btrfs_device_get_##name(const struct btrfs_device *dev) \
249{ \
250 return dev->name; \
251} \
252 \
253static inline void \
254btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
255{ \
256 dev->name = size; \
257}
258#endif
259
260BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
261BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
262BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
263
264enum btrfs_chunk_allocation_policy {
265 BTRFS_CHUNK_ALLOC_REGULAR,
266 BTRFS_CHUNK_ALLOC_ZONED,
267};
268
269/*
270 * Read policies for mirrored block group profiles, read picks the stripe based
271 * on these policies.
272 */
273enum btrfs_read_policy {
274 /* Use process PID to choose the stripe */
275 BTRFS_READ_POLICY_PID,
276 BTRFS_NR_READ_POLICY,
277};
278
279struct btrfs_fs_devices {
280 u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
281
282 /*
283 * UUID written into the btree blocks:
284 *
285 * - If metadata_uuid != fsid then super block must have
286 * BTRFS_FEATURE_INCOMPAT_METADATA_UUID flag set.
287 *
288 * - Following shall be true at all times:
289 * - metadata_uuid == btrfs_header::fsid
290 * - metadata_uuid == btrfs_dev_item::fsid
291 *
292 * - Relations between fsid and metadata_uuid in sb and fs_devices:
293 * - Normal:
294 * fs_devices->fsid == fs_devices->metadata_uuid == sb->fsid
295 * sb->metadata_uuid == 0
296 *
297 * - When the BTRFS_FEATURE_INCOMPAT_METADATA_UUID flag is set:
298 * fs_devices->fsid == sb->fsid
299 * fs_devices->metadata_uuid == sb->metadata_uuid
300 *
301 * - When in-memory fs_devices->temp_fsid is true
302 * fs_devices->fsid = random
303 * fs_devices->metadata_uuid == sb->fsid
304 */
305 u8 metadata_uuid[BTRFS_FSID_SIZE];
306
307 struct list_head fs_list;
308
309 /*
310 * Number of devices under this fsid including missing and
311 * replace-target device and excludes seed devices.
312 */
313 u64 num_devices;
314
315 /*
316 * The number of devices that successfully opened, including
317 * replace-target, excludes seed devices.
318 */
319 u64 open_devices;
320
321 /* The number of devices that are under the chunk allocation list. */
322 u64 rw_devices;
323
324 /* Count of missing devices under this fsid excluding seed device. */
325 u64 missing_devices;
326 u64 total_rw_bytes;
327
328 /*
329 * Count of devices from btrfs_super_block::num_devices for this fsid,
330 * which includes the seed device, excludes the transient replace-target
331 * device.
332 */
333 u64 total_devices;
334
335 /* Highest generation number of seen devices */
336 u64 latest_generation;
337
338 /*
339 * The mount device or a device with highest generation after removal
340 * or replace.
341 */
342 struct btrfs_device *latest_dev;
343
344 /*
345 * All of the devices in the filesystem, protected by a mutex so we can
346 * safely walk it to write out the super blocks without worrying about
347 * adding/removing by the multi-device code. Scrubbing super block can
348 * kick off supers writing by holding this mutex lock.
349 */
350 struct mutex device_list_mutex;
351
352 /* List of all devices, protected by device_list_mutex */
353 struct list_head devices;
354
355 /* Devices which can satisfy space allocation. Protected by * chunk_mutex. */
356 struct list_head alloc_list;
357
358 struct list_head seed_list;
359
360 /* Count fs-devices opened. */
361 int opened;
362
363 /* Set when we find or add a device that doesn't have the nonrot flag set. */
364 bool rotating;
365 /* Devices support TRIM/discard commands. */
366 bool discardable;
367 /* The filesystem is a seed filesystem. */
368 bool seeding;
369 /* The mount needs to use a randomly generated fsid. */
370 bool temp_fsid;
371
372 struct btrfs_fs_info *fs_info;
373 /* sysfs kobjects */
374 struct kobject fsid_kobj;
375 struct kobject *devices_kobj;
376 struct kobject *devinfo_kobj;
377 struct completion kobj_unregister;
378
379 enum btrfs_chunk_allocation_policy chunk_alloc_policy;
380
381 /* Policy used to read the mirrored stripes. */
382 enum btrfs_read_policy read_policy;
383};
384
385#define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info) \
386 - sizeof(struct btrfs_chunk)) \
387 / sizeof(struct btrfs_stripe) + 1)
388
389#define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE \
390 - 2 * sizeof(struct btrfs_disk_key) \
391 - 2 * sizeof(struct btrfs_chunk)) \
392 / sizeof(struct btrfs_stripe) + 1)
393
394struct btrfs_io_stripe {
395 struct btrfs_device *dev;
396 /* Block mapping. */
397 u64 physical;
398 u64 length;
399 bool is_scrub;
400 /* For the endio handler. */
401 struct btrfs_io_context *bioc;
402};
403
404struct btrfs_discard_stripe {
405 struct btrfs_device *dev;
406 u64 physical;
407 u64 length;
408};
409
410/*
411 * Context for IO subsmission for device stripe.
412 *
413 * - Track the unfinished mirrors for mirror based profiles
414 * Mirror based profiles are SINGLE/DUP/RAID1/RAID10.
415 *
416 * - Contain the logical -> physical mapping info
417 * Used by submit_stripe_bio() for mapping logical bio
418 * into physical device address.
419 *
420 * - Contain device replace info
421 * Used by handle_ops_on_dev_replace() to copy logical bios
422 * into the new device.
423 *
424 * - Contain RAID56 full stripe logical bytenrs
425 */
426struct btrfs_io_context {
427 refcount_t refs;
428 struct btrfs_fs_info *fs_info;
429 /* Taken from struct btrfs_chunk_map::type. */
430 u64 map_type;
431 struct bio *orig_bio;
432 atomic_t error;
433 u16 max_errors;
434
435 u64 logical;
436 u64 size;
437 /* Raid stripe tree ordered entry. */
438 struct list_head rst_ordered_entry;
439
440 /*
441 * The total number of stripes, including the extra duplicated
442 * stripe for replace.
443 */
444 u16 num_stripes;
445
446 /*
447 * The mirror_num of this bioc.
448 *
449 * This is for reads which use 0 as mirror_num, thus we should return a
450 * valid mirror_num (>0) for the reader.
451 */
452 u16 mirror_num;
453
454 /*
455 * The following two members are for dev-replace case only.
456 *
457 * @replace_nr_stripes: Number of duplicated stripes which need to be
458 * written to replace target.
459 * Should be <= 2 (2 for DUP, otherwise <= 1).
460 * @replace_stripe_src: The array indicates where the duplicated stripes
461 * are from.
462 *
463 * The @replace_stripe_src[] array is mostly for RAID56 cases.
464 * As non-RAID56 stripes share the same contents of the mapped range,
465 * thus no need to bother where the duplicated ones are from.
466 *
467 * But for RAID56 case, all stripes contain different contents, thus
468 * we need a way to know the mapping.
469 *
470 * There is an example for the two members, using a RAID5 write:
471 *
472 * num_stripes: 4 (3 + 1 duplicated write)
473 * stripes[0]: dev = devid 1, physical = X
474 * stripes[1]: dev = devid 2, physical = Y
475 * stripes[2]: dev = devid 3, physical = Z
476 * stripes[3]: dev = devid 0, physical = Y
477 *
478 * replace_nr_stripes = 1
479 * replace_stripe_src = 1 <- Means stripes[1] is involved in replace.
480 * The duplicated stripe index would be
481 * (@num_stripes - 1).
482 *
483 * Note, that we can still have cases replace_nr_stripes = 2 for DUP.
484 * In that case, all stripes share the same content, thus we don't
485 * need to bother @replace_stripe_src value at all.
486 */
487 u16 replace_nr_stripes;
488 s16 replace_stripe_src;
489 /*
490 * Logical bytenr of the full stripe start, only for RAID56 cases.
491 *
492 * When this value is set to other than (u64)-1, the stripes[] should
493 * follow this pattern:
494 *
495 * (real_stripes = num_stripes - replace_nr_stripes)
496 * (data_stripes = (is_raid6) ? (real_stripes - 2) : (real_stripes - 1))
497 *
498 * stripes[0]: The first data stripe
499 * stripes[1]: The second data stripe
500 * ...
501 * stripes[data_stripes - 1]: The last data stripe
502 * stripes[data_stripes]: The P stripe
503 * stripes[data_stripes + 1]: The Q stripe (only for RAID6).
504 */
505 u64 full_stripe_logical;
506 struct btrfs_io_stripe stripes[];
507};
508
509struct btrfs_device_info {
510 struct btrfs_device *dev;
511 u64 dev_offset;
512 u64 max_avail;
513 u64 total_avail;
514};
515
516struct btrfs_raid_attr {
517 u8 sub_stripes; /* sub_stripes info for map */
518 u8 dev_stripes; /* stripes per dev */
519 u8 devs_max; /* max devs to use */
520 u8 devs_min; /* min devs needed */
521 u8 tolerated_failures; /* max tolerated fail devs */
522 u8 devs_increment; /* ndevs has to be a multiple of this */
523 u8 ncopies; /* how many copies to data has */
524 u8 nparity; /* number of stripes worth of bytes to store
525 * parity information */
526 u8 mindev_error; /* error code if min devs requisite is unmet */
527 const char raid_name[8]; /* name of the raid */
528 u64 bg_flag; /* block group flag of the raid */
529};
530
531extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
532
533struct btrfs_chunk_map {
534 struct rb_node rb_node;
535 /* For mount time dev extent verification. */
536 int verified_stripes;
537 refcount_t refs;
538 u64 start;
539 u64 chunk_len;
540 u64 stripe_size;
541 u64 type;
542 int io_align;
543 int io_width;
544 int num_stripes;
545 int sub_stripes;
546 struct btrfs_io_stripe stripes[];
547};
548
549#define btrfs_chunk_map_size(n) (sizeof(struct btrfs_chunk_map) + \
550 (sizeof(struct btrfs_io_stripe) * (n)))
551
552static inline void btrfs_free_chunk_map(struct btrfs_chunk_map *map)
553{
554 if (map && refcount_dec_and_test(&map->refs)) {
555 ASSERT(RB_EMPTY_NODE(&map->rb_node));
556 kfree(map);
557 }
558}
559
560struct btrfs_balance_args;
561struct btrfs_balance_progress;
562struct btrfs_balance_control {
563 struct btrfs_balance_args data;
564 struct btrfs_balance_args meta;
565 struct btrfs_balance_args sys;
566
567 u64 flags;
568
569 struct btrfs_balance_progress stat;
570};
571
572/*
573 * Search for a given device by the set parameters
574 */
575struct btrfs_dev_lookup_args {
576 u64 devid;
577 u8 *uuid;
578 u8 *fsid;
579 bool missing;
580};
581
582/* We have to initialize to -1 because BTRFS_DEV_REPLACE_DEVID is 0 */
583#define BTRFS_DEV_LOOKUP_ARGS_INIT { .devid = (u64)-1 }
584
585#define BTRFS_DEV_LOOKUP_ARGS(name) \
586 struct btrfs_dev_lookup_args name = BTRFS_DEV_LOOKUP_ARGS_INIT
587
588enum btrfs_map_op {
589 BTRFS_MAP_READ,
590 BTRFS_MAP_WRITE,
591 BTRFS_MAP_GET_READ_MIRRORS,
592};
593
594static inline enum btrfs_map_op btrfs_op(struct bio *bio)
595{
596 switch (bio_op(bio)) {
597 case REQ_OP_WRITE:
598 case REQ_OP_ZONE_APPEND:
599 return BTRFS_MAP_WRITE;
600 default:
601 WARN_ON_ONCE(1);
602 fallthrough;
603 case REQ_OP_READ:
604 return BTRFS_MAP_READ;
605 }
606}
607
608static inline unsigned long btrfs_chunk_item_size(int num_stripes)
609{
610 ASSERT(num_stripes);
611 return sizeof(struct btrfs_chunk) +
612 sizeof(struct btrfs_stripe) * (num_stripes - 1);
613}
614
615/*
616 * Do the type safe conversion from stripe_nr to offset inside the chunk.
617 *
618 * @stripe_nr is u32, with left shift it can overflow u32 for chunks larger
619 * than 4G. This does the proper type cast to avoid overflow.
620 */
621static inline u64 btrfs_stripe_nr_to_offset(u32 stripe_nr)
622{
623 return (u64)stripe_nr << BTRFS_STRIPE_LEN_SHIFT;
624}
625
626void btrfs_get_bioc(struct btrfs_io_context *bioc);
627void btrfs_put_bioc(struct btrfs_io_context *bioc);
628int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
629 u64 logical, u64 *length,
630 struct btrfs_io_context **bioc_ret,
631 struct btrfs_io_stripe *smap, int *mirror_num_ret);
632int btrfs_map_repair_block(struct btrfs_fs_info *fs_info,
633 struct btrfs_io_stripe *smap, u64 logical,
634 u32 length, int mirror_num);
635struct btrfs_discard_stripe *btrfs_map_discard(struct btrfs_fs_info *fs_info,
636 u64 logical, u64 *length_ret,
637 u32 *num_stripes);
638int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
639int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
640struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans,
641 u64 type);
642void btrfs_mapping_tree_free(struct btrfs_fs_info *fs_info);
643int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
644 blk_mode_t flags, void *holder);
645struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags,
646 bool mount_arg_dev);
647int btrfs_forget_devices(dev_t devt);
648void btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
649void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices);
650void btrfs_assign_next_active_device(struct btrfs_device *device,
651 struct btrfs_device *this_dev);
652struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
653 u64 devid,
654 const char *devpath);
655int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
656 struct btrfs_dev_lookup_args *args,
657 const char *path);
658struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
659 const u64 *devid, const u8 *uuid,
660 const char *path);
661void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args);
662int btrfs_rm_device(struct btrfs_fs_info *fs_info,
663 struct btrfs_dev_lookup_args *args,
664 struct bdev_handle **bdev_handle);
665void __exit btrfs_cleanup_fs_uuids(void);
666int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
667int btrfs_grow_device(struct btrfs_trans_handle *trans,
668 struct btrfs_device *device, u64 new_size);
669struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices,
670 const struct btrfs_dev_lookup_args *args);
671int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
672int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
673int btrfs_balance(struct btrfs_fs_info *fs_info,
674 struct btrfs_balance_control *bctl,
675 struct btrfs_ioctl_balance_args *bargs);
676void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
677int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
678int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
679int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
680int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset);
681int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
682int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
683int btrfs_uuid_scan_kthread(void *data);
684bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset);
685void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
686int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
687 struct btrfs_ioctl_get_dev_stats *stats);
688int btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
689int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
690int btrfs_run_dev_stats(struct btrfs_trans_handle *trans);
691void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);
692void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);
693void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);
694int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
695 u64 logical, u64 len);
696unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
697 u64 logical);
698u64 btrfs_calc_stripe_length(const struct btrfs_chunk_map *map);
699int btrfs_nr_parity_stripes(u64 type);
700int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans,
701 struct btrfs_block_group *bg);
702int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);
703
704#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
705struct btrfs_chunk_map *btrfs_alloc_chunk_map(int num_stripes, gfp_t gfp);
706int btrfs_add_chunk_map(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map);
707#endif
708
709struct btrfs_chunk_map *btrfs_clone_chunk_map(struct btrfs_chunk_map *map, gfp_t gfp);
710struct btrfs_chunk_map *btrfs_find_chunk_map(struct btrfs_fs_info *fs_info,
711 u64 logical, u64 length);
712struct btrfs_chunk_map *btrfs_find_chunk_map_nolock(struct btrfs_fs_info *fs_info,
713 u64 logical, u64 length);
714struct btrfs_chunk_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
715 u64 logical, u64 length);
716void btrfs_remove_chunk_map(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map);
717void btrfs_release_disk_super(struct btrfs_super_block *super);
718
719static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
720 int index)
721{
722 atomic_inc(dev->dev_stat_values + index);
723 /*
724 * This memory barrier orders stores updating statistics before stores
725 * updating dev_stats_ccnt.
726 *
727 * It pairs with smp_rmb() in btrfs_run_dev_stats().
728 */
729 smp_mb__before_atomic();
730 atomic_inc(&dev->dev_stats_ccnt);
731}
732
733static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
734 int index)
735{
736 return atomic_read(dev->dev_stat_values + index);
737}
738
739static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
740 int index)
741{
742 int ret;
743
744 ret = atomic_xchg(dev->dev_stat_values + index, 0);
745 /*
746 * atomic_xchg implies a full memory barriers as per atomic_t.txt:
747 * - RMW operations that have a return value are fully ordered;
748 *
749 * This implicit memory barriers is paired with the smp_rmb in
750 * btrfs_run_dev_stats
751 */
752 atomic_inc(&dev->dev_stats_ccnt);
753 return ret;
754}
755
756static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
757 int index, unsigned long val)
758{
759 atomic_set(dev->dev_stat_values + index, val);
760 /*
761 * This memory barrier orders stores updating statistics before stores
762 * updating dev_stats_ccnt.
763 *
764 * It pairs with smp_rmb() in btrfs_run_dev_stats().
765 */
766 smp_mb__before_atomic();
767 atomic_inc(&dev->dev_stats_ccnt);
768}
769
770static inline const char *btrfs_dev_name(const struct btrfs_device *device)
771{
772 if (!device || test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state))
773 return "<missing disk>";
774 else
775 return rcu_str_deref(device->name);
776}
777
778void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
779
780struct list_head * __attribute_const__ btrfs_get_fs_uuids(void);
781bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
782 struct btrfs_device *failing_dev);
783void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info,
784 struct block_device *bdev,
785 const char *device_path);
786
787enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags);
788int btrfs_bg_type_to_factor(u64 flags);
789const char *btrfs_bg_type_to_raid_name(u64 flags);
790int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
791bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical);
792
793bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr);
794u8 *btrfs_sb_fsid_ptr(struct btrfs_super_block *sb);
795
796#endif