1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6 #ifndef BTRFS_VOLUMES_H
7 #define BTRFS_VOLUMES_H
8
9 #include <linux/bio.h>
10 #include <linux/sort.h>
11 #include <linux/btrfs.h>
12 #include "async-thread.h"
13
14 #define BTRFS_MAX_DATA_CHUNK_SIZE (10ULL * SZ_1G)
15
16 extern struct mutex uuid_mutex;
17
18 #define BTRFS_STRIPE_LEN SZ_64K
19
20 struct buffer_head;
21 struct btrfs_pending_bios {
22 struct bio *head;
23 struct bio *tail;
24 };
25
26 struct btrfs_io_geometry {
27 /* remaining bytes before crossing a stripe */
28 u64 len;
29 /* offset of logical address in chunk */
30 u64 offset;
31 /* length of single IO stripe */
32 u64 stripe_len;
33 /* number of stripe where address falls */
34 u64 stripe_nr;
35 /* offset of address in stripe */
36 u64 stripe_offset;
37 /* offset of raid56 stripe into the chunk */
38 u64 raid56_stripe_offset;
39 };
40
41 /*
42 * Use sequence counter to get consistent device stat data on
43 * 32-bit processors.
44 */
45 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
46 #include <linux/seqlock.h>
47 #define __BTRFS_NEED_DEVICE_DATA_ORDERED
48 #define btrfs_device_data_ordered_init(device) \
49 seqcount_init(&device->data_seqcount)
50 #else
51 #define btrfs_device_data_ordered_init(device) do { } while (0)
52 #endif
53
54 #define BTRFS_DEV_STATE_WRITEABLE (0)
55 #define BTRFS_DEV_STATE_IN_FS_METADATA (1)
56 #define BTRFS_DEV_STATE_MISSING (2)
57 #define BTRFS_DEV_STATE_REPLACE_TGT (3)
58 #define BTRFS_DEV_STATE_FLUSH_SENT (4)
59
60 struct btrfs_device {
61 struct list_head dev_list; /* device_list_mutex */
62 struct list_head dev_alloc_list; /* chunk mutex */
63 struct list_head post_commit_list; /* chunk mutex */
64 struct btrfs_fs_devices *fs_devices;
65 struct btrfs_fs_info *fs_info;
66
67 struct rcu_string *name;
68
69 u64 generation;
70
71 spinlock_t io_lock ____cacheline_aligned;
72 int running_pending;
73 /* regular prio bios */
74 struct btrfs_pending_bios pending_bios;
75 /* sync bios */
76 struct btrfs_pending_bios pending_sync_bios;
77
78 struct block_device *bdev;
79
80 /* the mode sent to blkdev_get */
81 fmode_t mode;
82
83 unsigned long dev_state;
84 blk_status_t last_flush_error;
85
86 #ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
87 seqcount_t data_seqcount;
88 #endif
89
90 /* the internal btrfs device id */
91 u64 devid;
92
93 /* size of the device in memory */
94 u64 total_bytes;
95
96 /* size of the device on disk */
97 u64 disk_total_bytes;
98
99 /* bytes used */
100 u64 bytes_used;
101
102 /* optimal io alignment for this device */
103 u32 io_align;
104
105 /* optimal io width for this device */
106 u32 io_width;
107 /* type and info about this device */
108 u64 type;
109
110 /* minimal io size for this device */
111 u32 sector_size;
112
113 /* physical drive uuid (or lvm uuid) */
114 u8 uuid[BTRFS_UUID_SIZE];
115
116 /*
117 * size of the device on the current transaction
118 *
119 * This variant is update when committing the transaction,
120 * and protected by chunk mutex
121 */
122 u64 commit_total_bytes;
123
124 /* bytes used on the current transaction */
125 u64 commit_bytes_used;
126
127 /* for sending down flush barriers */
128 struct bio *flush_bio;
129 struct completion flush_wait;
130
131 /* per-device scrub information */
132 struct scrub_ctx *scrub_ctx;
133
134 struct btrfs_work work;
135
136 /* readahead state */
137 atomic_t reada_in_flight;
138 u64 reada_next;
139 struct reada_zone *reada_curr_zone;
140 struct radix_tree_root reada_zones;
141 struct radix_tree_root reada_extents;
142
143 /* disk I/O failure stats. For detailed description refer to
144 * enum btrfs_dev_stat_values in ioctl.h */
145 int dev_stats_valid;
146
147 /* Counter to record the change of device stats */
148 atomic_t dev_stats_ccnt;
149 atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
150
151 struct extent_io_tree alloc_state;
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) \
160 static inline u64 \
161 btrfs_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 \
173 static inline void \
174 btrfs_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) \
184 static inline u64 \
185 btrfs_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 \
195 static inline void \
196 btrfs_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) \
204 static inline u64 \
205 btrfs_device_get_##name(const struct btrfs_device *dev) \
206 { \
207 return dev->name; \
208 } \
209 \
210 static inline void \
211 btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
212 { \
213 dev->name = size; \
214 }
215 #endif
216
217 BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
218 BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
219 BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
220
221 struct btrfs_fs_devices {
222 u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
223 u8 metadata_uuid[BTRFS_FSID_SIZE];
224 bool fsid_change;
225 struct list_head fs_list;
226
227 u64 num_devices;
228 u64 open_devices;
229 u64 rw_devices;
230 u64 missing_devices;
231 u64 total_rw_bytes;
232 u64 total_devices;
233
234 /* Highest generation number of seen devices */
235 u64 latest_generation;
236
237 struct block_device *latest_bdev;
238
239 /* all of the devices in the FS, protected by a mutex
240 * so we can safely walk it to write out the supers without
241 * worrying about add/remove by the multi-device code.
242 * Scrubbing super can kick off supers writing by holding
243 * this mutex lock.
244 */
245 struct mutex device_list_mutex;
246
247 /* List of all devices, protected by device_list_mutex */
248 struct list_head devices;
249
250 /*
251 * Devices which can satisfy space allocation. Protected by
252 * chunk_mutex
253 */
254 struct list_head alloc_list;
255
256 struct btrfs_fs_devices *seed;
257 int seeding;
258
259 int opened;
260
261 /* set when we find or add a device that doesn't have the
262 * nonrot flag set
263 */
264 int rotating;
265
266 struct btrfs_fs_info *fs_info;
267 /* sysfs kobjects */
268 struct kobject fsid_kobj;
269 struct kobject *device_dir_kobj;
270 struct completion kobj_unregister;
271 };
272
273 #define BTRFS_BIO_INLINE_CSUM_SIZE 64
274
275 #define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info) \
276 - sizeof(struct btrfs_chunk)) \
277 / sizeof(struct btrfs_stripe) + 1)
278
279 #define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE \
280 - 2 * sizeof(struct btrfs_disk_key) \
281 - 2 * sizeof(struct btrfs_chunk)) \
282 / sizeof(struct btrfs_stripe) + 1)
283
284 /*
285 * we need the mirror number and stripe index to be passed around
286 * the call chain while we are processing end_io (especially errors).
287 * Really, what we need is a btrfs_bio structure that has this info
288 * and is properly sized with its stripe array, but we're not there
289 * quite yet. We have our own btrfs bioset, and all of the bios
290 * we allocate are actually btrfs_io_bios. We'll cram as much of
291 * struct btrfs_bio as we can into this over time.
292 */
293 struct btrfs_io_bio {
294 unsigned int mirror_num;
295 unsigned int stripe_index;
296 u64 logical;
297 u8 *csum;
298 u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
299 struct bvec_iter iter;
300 /*
301 * This member must come last, bio_alloc_bioset will allocate enough
302 * bytes for entire btrfs_io_bio but relies on bio being last.
303 */
304 struct bio bio;
305 };
306
btrfs_io_bio(struct bio * bio)307 static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
308 {
309 return container_of(bio, struct btrfs_io_bio, bio);
310 }
311
btrfs_io_bio_free_csum(struct btrfs_io_bio * io_bio)312 static inline void btrfs_io_bio_free_csum(struct btrfs_io_bio *io_bio)
313 {
314 if (io_bio->csum != io_bio->csum_inline) {
315 kfree(io_bio->csum);
316 io_bio->csum = NULL;
317 }
318 }
319
320 struct btrfs_bio_stripe {
321 struct btrfs_device *dev;
322 u64 physical;
323 u64 length; /* only used for discard mappings */
324 };
325
326 struct btrfs_bio {
327 refcount_t refs;
328 atomic_t stripes_pending;
329 struct btrfs_fs_info *fs_info;
330 u64 map_type; /* get from map_lookup->type */
331 bio_end_io_t *end_io;
332 struct bio *orig_bio;
333 void *private;
334 atomic_t error;
335 int max_errors;
336 int num_stripes;
337 int mirror_num;
338 int num_tgtdevs;
339 int *tgtdev_map;
340 /*
341 * logical block numbers for the start of each stripe
342 * The last one or two are p/q. These are sorted,
343 * so raid_map[0] is the start of our full stripe
344 */
345 u64 *raid_map;
346 struct btrfs_bio_stripe stripes[];
347 };
348
349 struct btrfs_device_info {
350 struct btrfs_device *dev;
351 u64 dev_offset;
352 u64 max_avail;
353 u64 total_avail;
354 };
355
356 struct btrfs_raid_attr {
357 u8 sub_stripes; /* sub_stripes info for map */
358 u8 dev_stripes; /* stripes per dev */
359 u8 devs_max; /* max devs to use */
360 u8 devs_min; /* min devs needed */
361 u8 tolerated_failures; /* max tolerated fail devs */
362 u8 devs_increment; /* ndevs has to be a multiple of this */
363 u8 ncopies; /* how many copies to data has */
364 u8 nparity; /* number of stripes worth of bytes to store
365 * parity information */
366 u8 mindev_error; /* error code if min devs requisite is unmet */
367 const char raid_name[8]; /* name of the raid */
368 u64 bg_flag; /* block group flag of the raid */
369 };
370
371 extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
372
373 struct map_lookup {
374 u64 type;
375 int io_align;
376 int io_width;
377 u64 stripe_len;
378 int num_stripes;
379 int sub_stripes;
380 int verified_stripes; /* For mount time dev extent verification */
381 struct btrfs_bio_stripe stripes[];
382 };
383
384 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
385 (sizeof(struct btrfs_bio_stripe) * (n)))
386
387 struct btrfs_balance_args;
388 struct btrfs_balance_progress;
389 struct btrfs_balance_control {
390 struct btrfs_balance_args data;
391 struct btrfs_balance_args meta;
392 struct btrfs_balance_args sys;
393
394 u64 flags;
395
396 struct btrfs_balance_progress stat;
397 };
398
399 enum btrfs_map_op {
400 BTRFS_MAP_READ,
401 BTRFS_MAP_WRITE,
402 BTRFS_MAP_DISCARD,
403 BTRFS_MAP_GET_READ_MIRRORS,
404 };
405
btrfs_op(struct bio * bio)406 static inline enum btrfs_map_op btrfs_op(struct bio *bio)
407 {
408 switch (bio_op(bio)) {
409 case REQ_OP_DISCARD:
410 return BTRFS_MAP_DISCARD;
411 case REQ_OP_WRITE:
412 return BTRFS_MAP_WRITE;
413 default:
414 WARN_ON_ONCE(1);
415 /* fall through */
416 case REQ_OP_READ:
417 return BTRFS_MAP_READ;
418 }
419 }
420
421 void btrfs_get_bbio(struct btrfs_bio *bbio);
422 void btrfs_put_bbio(struct btrfs_bio *bbio);
423 int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
424 u64 logical, u64 *length,
425 struct btrfs_bio **bbio_ret, int mirror_num);
426 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
427 u64 logical, u64 *length,
428 struct btrfs_bio **bbio_ret);
429 int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
430 u64 logical, u64 len, struct btrfs_io_geometry *io_geom);
431 int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
432 u64 physical, u64 **logical, int *naddrs, int *stripe_len);
433 int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
434 int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
435 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, u64 type);
436 void btrfs_mapping_tree_free(struct extent_map_tree *tree);
437 blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
438 int mirror_num, int async_submit);
439 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
440 fmode_t flags, void *holder);
441 struct btrfs_device *btrfs_scan_one_device(const char *path,
442 fmode_t flags, void *holder);
443 int btrfs_forget_devices(const char *path);
444 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
445 void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices, int step);
446 void btrfs_assign_next_active_device(struct btrfs_device *device,
447 struct btrfs_device *this_dev);
448 struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
449 u64 devid,
450 const char *devpath);
451 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
452 const u64 *devid,
453 const u8 *uuid);
454 void btrfs_free_device(struct btrfs_device *device);
455 int btrfs_rm_device(struct btrfs_fs_info *fs_info,
456 const char *device_path, u64 devid);
457 void __exit btrfs_cleanup_fs_uuids(void);
458 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
459 int btrfs_grow_device(struct btrfs_trans_handle *trans,
460 struct btrfs_device *device, u64 new_size);
461 struct btrfs_device *btrfs_find_device(struct btrfs_fs_devices *fs_devices,
462 u64 devid, u8 *uuid, u8 *fsid, bool seed);
463 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
464 int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
465 int btrfs_balance(struct btrfs_fs_info *fs_info,
466 struct btrfs_balance_control *bctl,
467 struct btrfs_ioctl_balance_args *bargs);
468 void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
469 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
470 int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
471 int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
472 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
473 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
474 int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info);
475 int btrfs_chunk_readonly(struct btrfs_fs_info *fs_info, u64 chunk_offset);
476 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
477 u64 *start, u64 *max_avail);
478 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
479 int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
480 struct btrfs_ioctl_get_dev_stats *stats);
481 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
482 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
483 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans);
484 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);
485 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);
486 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);
487 void btrfs_scratch_superblocks(struct block_device *bdev, const char *device_path);
488 int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
489 u64 logical, u64 len);
490 unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
491 u64 logical);
492 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
493 u64 chunk_offset, u64 chunk_size);
494 int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);
495 struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
496 u64 logical, u64 length);
497
btrfs_dev_stat_inc(struct btrfs_device * dev,int index)498 static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
499 int index)
500 {
501 atomic_inc(dev->dev_stat_values + index);
502 /*
503 * This memory barrier orders stores updating statistics before stores
504 * updating dev_stats_ccnt.
505 *
506 * It pairs with smp_rmb() in btrfs_run_dev_stats().
507 */
508 smp_mb__before_atomic();
509 atomic_inc(&dev->dev_stats_ccnt);
510 }
511
btrfs_dev_stat_read(struct btrfs_device * dev,int index)512 static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
513 int index)
514 {
515 return atomic_read(dev->dev_stat_values + index);
516 }
517
btrfs_dev_stat_read_and_reset(struct btrfs_device * dev,int index)518 static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
519 int index)
520 {
521 int ret;
522
523 ret = atomic_xchg(dev->dev_stat_values + index, 0);
524 /*
525 * atomic_xchg implies a full memory barriers as per atomic_t.txt:
526 * - RMW operations that have a return value are fully ordered;
527 *
528 * This implicit memory barriers is paired with the smp_rmb in
529 * btrfs_run_dev_stats
530 */
531 atomic_inc(&dev->dev_stats_ccnt);
532 return ret;
533 }
534
btrfs_dev_stat_set(struct btrfs_device * dev,int index,unsigned long val)535 static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
536 int index, unsigned long val)
537 {
538 atomic_set(dev->dev_stat_values + index, val);
539 /*
540 * This memory barrier orders stores updating statistics before stores
541 * updating dev_stats_ccnt.
542 *
543 * It pairs with smp_rmb() in btrfs_run_dev_stats().
544 */
545 smp_mb__before_atomic();
546 atomic_inc(&dev->dev_stats_ccnt);
547 }
548
549 /*
550 * Convert block group flags (BTRFS_BLOCK_GROUP_*) to btrfs_raid_types, which
551 * can be used as index to access btrfs_raid_array[].
552 */
btrfs_bg_flags_to_raid_index(u64 flags)553 static inline enum btrfs_raid_types btrfs_bg_flags_to_raid_index(u64 flags)
554 {
555 if (flags & BTRFS_BLOCK_GROUP_RAID10)
556 return BTRFS_RAID_RAID10;
557 else if (flags & BTRFS_BLOCK_GROUP_RAID1)
558 return BTRFS_RAID_RAID1;
559 else if (flags & BTRFS_BLOCK_GROUP_DUP)
560 return BTRFS_RAID_DUP;
561 else if (flags & BTRFS_BLOCK_GROUP_RAID0)
562 return BTRFS_RAID_RAID0;
563 else if (flags & BTRFS_BLOCK_GROUP_RAID5)
564 return BTRFS_RAID_RAID5;
565 else if (flags & BTRFS_BLOCK_GROUP_RAID6)
566 return BTRFS_RAID_RAID6;
567
568 return BTRFS_RAID_SINGLE; /* BTRFS_BLOCK_GROUP_SINGLE */
569 }
570
571 void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
572
573 struct list_head *btrfs_get_fs_uuids(void);
574 void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info);
575 void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info);
576 bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
577 struct btrfs_device *failing_dev);
578
579 int btrfs_bg_type_to_factor(u64 flags);
580 const char *btrfs_bg_type_to_raid_name(u64 flags);
581 int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
582
583 #endif
584