xref: /openbmc/linux/fs/btrfs/volumes.h (revision 66a28915)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 2007 Oracle.  All rights reserved.
4  */
5 
6 #ifndef BTRFS_VOLUMES_H
7 #define BTRFS_VOLUMES_H
8 
9 #include <linux/bio.h>
10 #include <linux/sort.h>
11 #include <linux/btrfs.h>
12 #include "async-thread.h"
13 
14 #define BTRFS_MAX_DATA_CHUNK_SIZE	(10ULL * SZ_1G)
15 
16 extern struct mutex uuid_mutex;
17 
18 #define BTRFS_STRIPE_LEN	SZ_64K
19 
20 struct btrfs_io_geometry {
21 	/* remaining bytes before crossing a stripe */
22 	u64 len;
23 	/* offset of logical address in chunk */
24 	u64 offset;
25 	/* length of single IO stripe */
26 	u64 stripe_len;
27 	/* number of stripe where address falls */
28 	u64 stripe_nr;
29 	/* offset of address in stripe */
30 	u64 stripe_offset;
31 	/* offset of raid56 stripe into the chunk */
32 	u64 raid56_stripe_offset;
33 };
34 
35 /*
36  * Use sequence counter to get consistent device stat data on
37  * 32-bit processors.
38  */
39 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
40 #include <linux/seqlock.h>
41 #define __BTRFS_NEED_DEVICE_DATA_ORDERED
42 #define btrfs_device_data_ordered_init(device, info)				\
43 	seqcount_mutex_init(&device->data_seqcount, &info->chunk_mutex)
44 #else
45 #define btrfs_device_data_ordered_init(device, info) do { } while (0)
46 #endif
47 
48 #define BTRFS_DEV_STATE_WRITEABLE	(0)
49 #define BTRFS_DEV_STATE_IN_FS_METADATA	(1)
50 #define BTRFS_DEV_STATE_MISSING		(2)
51 #define BTRFS_DEV_STATE_REPLACE_TGT	(3)
52 #define BTRFS_DEV_STATE_FLUSH_SENT	(4)
53 #define BTRFS_DEV_STATE_NO_READA	(5)
54 
55 struct btrfs_zoned_device_info;
56 
57 struct btrfs_device {
58 	struct list_head dev_list; /* device_list_mutex */
59 	struct list_head dev_alloc_list; /* chunk mutex */
60 	struct list_head post_commit_list; /* chunk mutex */
61 	struct btrfs_fs_devices *fs_devices;
62 	struct btrfs_fs_info *fs_info;
63 
64 	struct rcu_string __rcu *name;
65 
66 	u64 generation;
67 
68 	struct block_device *bdev;
69 
70 	struct btrfs_zoned_device_info *zone_info;
71 
72 	/* the mode sent to blkdev_get */
73 	fmode_t mode;
74 
75 	unsigned long dev_state;
76 	blk_status_t last_flush_error;
77 
78 #ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
79 	/* A seqcount_t with associated chunk_mutex (for lockdep) */
80 	seqcount_mutex_t data_seqcount;
81 #endif
82 
83 	/* the internal btrfs device id */
84 	u64 devid;
85 
86 	/* size of the device in memory */
87 	u64 total_bytes;
88 
89 	/* size of the device on disk */
90 	u64 disk_total_bytes;
91 
92 	/* bytes used */
93 	u64 bytes_used;
94 
95 	/* optimal io alignment for this device */
96 	u32 io_align;
97 
98 	/* optimal io width for this device */
99 	u32 io_width;
100 	/* type and info about this device */
101 	u64 type;
102 
103 	/* minimal io size for this device */
104 	u32 sector_size;
105 
106 	/* physical drive uuid (or lvm uuid) */
107 	u8 uuid[BTRFS_UUID_SIZE];
108 
109 	/*
110 	 * size of the device on the current transaction
111 	 *
112 	 * This variant is update when committing the transaction,
113 	 * and protected by chunk mutex
114 	 */
115 	u64 commit_total_bytes;
116 
117 	/* bytes used on the current transaction */
118 	u64 commit_bytes_used;
119 
120 	/* for sending down flush barriers */
121 	struct bio *flush_bio;
122 	struct completion flush_wait;
123 
124 	/* per-device scrub information */
125 	struct scrub_ctx *scrub_ctx;
126 
127 	/* readahead state */
128 	atomic_t reada_in_flight;
129 	u64 reada_next;
130 	struct reada_zone *reada_curr_zone;
131 	struct radix_tree_root reada_zones;
132 	struct radix_tree_root reada_extents;
133 
134 	/* disk I/O failure stats. For detailed description refer to
135 	 * enum btrfs_dev_stat_values in ioctl.h */
136 	int dev_stats_valid;
137 
138 	/* Counter to record the change of device stats */
139 	atomic_t dev_stats_ccnt;
140 	atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
141 
142 	struct extent_io_tree alloc_state;
143 
144 	struct completion kobj_unregister;
145 	/* For sysfs/FSID/devinfo/devid/ */
146 	struct kobject devid_kobj;
147 };
148 
149 /*
150  * If we read those variants at the context of their own lock, we needn't
151  * use the following helpers, reading them directly is safe.
152  */
153 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
154 #define BTRFS_DEVICE_GETSET_FUNCS(name)					\
155 static inline u64							\
156 btrfs_device_get_##name(const struct btrfs_device *dev)			\
157 {									\
158 	u64 size;							\
159 	unsigned int seq;						\
160 									\
161 	do {								\
162 		seq = read_seqcount_begin(&dev->data_seqcount);		\
163 		size = dev->name;					\
164 	} while (read_seqcount_retry(&dev->data_seqcount, seq));	\
165 	return size;							\
166 }									\
167 									\
168 static inline void							\
169 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
170 {									\
171 	write_seqcount_begin(&dev->data_seqcount);			\
172 	dev->name = size;						\
173 	write_seqcount_end(&dev->data_seqcount);			\
174 }
175 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
176 #define BTRFS_DEVICE_GETSET_FUNCS(name)					\
177 static inline u64							\
178 btrfs_device_get_##name(const struct btrfs_device *dev)			\
179 {									\
180 	u64 size;							\
181 									\
182 	preempt_disable();						\
183 	size = dev->name;						\
184 	preempt_enable();						\
185 	return size;							\
186 }									\
187 									\
188 static inline void							\
189 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
190 {									\
191 	preempt_disable();						\
192 	dev->name = size;						\
193 	preempt_enable();						\
194 }
195 #else
196 #define BTRFS_DEVICE_GETSET_FUNCS(name)					\
197 static inline u64							\
198 btrfs_device_get_##name(const struct btrfs_device *dev)			\
199 {									\
200 	return dev->name;						\
201 }									\
202 									\
203 static inline void							\
204 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
205 {									\
206 	dev->name = size;						\
207 }
208 #endif
209 
210 BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
211 BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
212 BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
213 
214 enum btrfs_chunk_allocation_policy {
215 	BTRFS_CHUNK_ALLOC_REGULAR,
216 };
217 
218 /*
219  * Read policies for mirrored block group profiles, read picks the stripe based
220  * on these policies.
221  */
222 enum btrfs_read_policy {
223 	/* Use process PID to choose the stripe */
224 	BTRFS_READ_POLICY_PID,
225 	BTRFS_NR_READ_POLICY,
226 };
227 
228 struct btrfs_fs_devices {
229 	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
230 	u8 metadata_uuid[BTRFS_FSID_SIZE];
231 	bool fsid_change;
232 	struct list_head fs_list;
233 
234 	u64 num_devices;
235 	u64 open_devices;
236 	u64 rw_devices;
237 	u64 missing_devices;
238 	u64 total_rw_bytes;
239 	u64 total_devices;
240 
241 	/* Highest generation number of seen devices */
242 	u64 latest_generation;
243 
244 	struct block_device *latest_bdev;
245 
246 	/* all of the devices in the FS, protected by a mutex
247 	 * so we can safely walk it to write out the supers without
248 	 * worrying about add/remove by the multi-device code.
249 	 * Scrubbing super can kick off supers writing by holding
250 	 * this mutex lock.
251 	 */
252 	struct mutex device_list_mutex;
253 
254 	/* List of all devices, protected by device_list_mutex */
255 	struct list_head devices;
256 
257 	/*
258 	 * Devices which can satisfy space allocation. Protected by
259 	 * chunk_mutex
260 	 */
261 	struct list_head alloc_list;
262 
263 	struct list_head seed_list;
264 	bool seeding;
265 
266 	int opened;
267 
268 	/* set when we find or add a device that doesn't have the
269 	 * nonrot flag set
270 	 */
271 	bool rotating;
272 
273 	struct btrfs_fs_info *fs_info;
274 	/* sysfs kobjects */
275 	struct kobject fsid_kobj;
276 	struct kobject *devices_kobj;
277 	struct kobject *devinfo_kobj;
278 	struct completion kobj_unregister;
279 
280 	enum btrfs_chunk_allocation_policy chunk_alloc_policy;
281 
282 	/* Policy used to read the mirrored stripes */
283 	enum btrfs_read_policy read_policy;
284 };
285 
286 #define BTRFS_BIO_INLINE_CSUM_SIZE	64
287 
288 #define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info)	\
289 			- sizeof(struct btrfs_chunk))		\
290 			/ sizeof(struct btrfs_stripe) + 1)
291 
292 #define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE	\
293 				- 2 * sizeof(struct btrfs_disk_key)	\
294 				- 2 * sizeof(struct btrfs_chunk))	\
295 				/ sizeof(struct btrfs_stripe) + 1)
296 
297 /*
298  * we need the mirror number and stripe index to be passed around
299  * the call chain while we are processing end_io (especially errors).
300  * Really, what we need is a btrfs_bio structure that has this info
301  * and is properly sized with its stripe array, but we're not there
302  * quite yet.  We have our own btrfs bioset, and all of the bios
303  * we allocate are actually btrfs_io_bios.  We'll cram as much of
304  * struct btrfs_bio as we can into this over time.
305  */
306 struct btrfs_io_bio {
307 	unsigned int mirror_num;
308 	struct btrfs_device *device;
309 	u64 logical;
310 	u8 *csum;
311 	u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
312 	struct bvec_iter iter;
313 	/*
314 	 * This member must come last, bio_alloc_bioset will allocate enough
315 	 * bytes for entire btrfs_io_bio but relies on bio being last.
316 	 */
317 	struct bio bio;
318 };
319 
320 static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
321 {
322 	return container_of(bio, struct btrfs_io_bio, bio);
323 }
324 
325 static inline void btrfs_io_bio_free_csum(struct btrfs_io_bio *io_bio)
326 {
327 	if (io_bio->csum != io_bio->csum_inline) {
328 		kfree(io_bio->csum);
329 		io_bio->csum = NULL;
330 	}
331 }
332 
333 struct btrfs_bio_stripe {
334 	struct btrfs_device *dev;
335 	u64 physical;
336 	u64 length; /* only used for discard mappings */
337 };
338 
339 struct btrfs_bio {
340 	refcount_t refs;
341 	atomic_t stripes_pending;
342 	struct btrfs_fs_info *fs_info;
343 	u64 map_type; /* get from map_lookup->type */
344 	bio_end_io_t *end_io;
345 	struct bio *orig_bio;
346 	void *private;
347 	atomic_t error;
348 	int max_errors;
349 	int num_stripes;
350 	int mirror_num;
351 	int num_tgtdevs;
352 	int *tgtdev_map;
353 	/*
354 	 * logical block numbers for the start of each stripe
355 	 * The last one or two are p/q.  These are sorted,
356 	 * so raid_map[0] is the start of our full stripe
357 	 */
358 	u64 *raid_map;
359 	struct btrfs_bio_stripe stripes[];
360 };
361 
362 struct btrfs_device_info {
363 	struct btrfs_device *dev;
364 	u64 dev_offset;
365 	u64 max_avail;
366 	u64 total_avail;
367 };
368 
369 struct btrfs_raid_attr {
370 	u8 sub_stripes;		/* sub_stripes info for map */
371 	u8 dev_stripes;		/* stripes per dev */
372 	u8 devs_max;		/* max devs to use */
373 	u8 devs_min;		/* min devs needed */
374 	u8 tolerated_failures;	/* max tolerated fail devs */
375 	u8 devs_increment;	/* ndevs has to be a multiple of this */
376 	u8 ncopies;		/* how many copies to data has */
377 	u8 nparity;		/* number of stripes worth of bytes to store
378 				 * parity information */
379 	u8 mindev_error;	/* error code if min devs requisite is unmet */
380 	const char raid_name[8]; /* name of the raid */
381 	u64 bg_flag;		/* block group flag of the raid */
382 };
383 
384 extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
385 
386 struct map_lookup {
387 	u64 type;
388 	int io_align;
389 	int io_width;
390 	u64 stripe_len;
391 	int num_stripes;
392 	int sub_stripes;
393 	int verified_stripes; /* For mount time dev extent verification */
394 	struct btrfs_bio_stripe stripes[];
395 };
396 
397 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
398 			    (sizeof(struct btrfs_bio_stripe) * (n)))
399 
400 struct btrfs_balance_args;
401 struct btrfs_balance_progress;
402 struct btrfs_balance_control {
403 	struct btrfs_balance_args data;
404 	struct btrfs_balance_args meta;
405 	struct btrfs_balance_args sys;
406 
407 	u64 flags;
408 
409 	struct btrfs_balance_progress stat;
410 };
411 
412 enum btrfs_map_op {
413 	BTRFS_MAP_READ,
414 	BTRFS_MAP_WRITE,
415 	BTRFS_MAP_DISCARD,
416 	BTRFS_MAP_GET_READ_MIRRORS,
417 };
418 
419 static inline enum btrfs_map_op btrfs_op(struct bio *bio)
420 {
421 	switch (bio_op(bio)) {
422 	case REQ_OP_DISCARD:
423 		return BTRFS_MAP_DISCARD;
424 	case REQ_OP_WRITE:
425 		return BTRFS_MAP_WRITE;
426 	default:
427 		WARN_ON_ONCE(1);
428 		fallthrough;
429 	case REQ_OP_READ:
430 		return BTRFS_MAP_READ;
431 	}
432 }
433 
434 void btrfs_get_bbio(struct btrfs_bio *bbio);
435 void btrfs_put_bbio(struct btrfs_bio *bbio);
436 int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
437 		    u64 logical, u64 *length,
438 		    struct btrfs_bio **bbio_ret, int mirror_num);
439 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
440 		     u64 logical, u64 *length,
441 		     struct btrfs_bio **bbio_ret);
442 int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
443 		u64 logical, u64 len, struct btrfs_io_geometry *io_geom);
444 int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
445 int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
446 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, u64 type);
447 void btrfs_mapping_tree_free(struct extent_map_tree *tree);
448 blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
449 			   int mirror_num);
450 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
451 		       fmode_t flags, void *holder);
452 struct btrfs_device *btrfs_scan_one_device(const char *path,
453 					   fmode_t flags, void *holder);
454 int btrfs_forget_devices(const char *path);
455 void btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
456 void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices);
457 void btrfs_assign_next_active_device(struct btrfs_device *device,
458 				     struct btrfs_device *this_dev);
459 struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
460 						  u64 devid,
461 						  const char *devpath);
462 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
463 					const u64 *devid,
464 					const u8 *uuid);
465 void btrfs_free_device(struct btrfs_device *device);
466 int btrfs_rm_device(struct btrfs_fs_info *fs_info,
467 		    const char *device_path, u64 devid);
468 void __exit btrfs_cleanup_fs_uuids(void);
469 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
470 int btrfs_grow_device(struct btrfs_trans_handle *trans,
471 		      struct btrfs_device *device, u64 new_size);
472 struct btrfs_device *btrfs_find_device(struct btrfs_fs_devices *fs_devices,
473 				       u64 devid, u8 *uuid, u8 *fsid);
474 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
475 int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
476 int btrfs_balance(struct btrfs_fs_info *fs_info,
477 		  struct btrfs_balance_control *bctl,
478 		  struct btrfs_ioctl_balance_args *bargs);
479 void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
480 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
481 int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
482 int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
483 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
484 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
485 int btrfs_uuid_scan_kthread(void *data);
486 int btrfs_chunk_readonly(struct btrfs_fs_info *fs_info, u64 chunk_offset);
487 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
488 			 u64 *start, u64 *max_avail);
489 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
490 int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
491 			struct btrfs_ioctl_get_dev_stats *stats);
492 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
493 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
494 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans);
495 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);
496 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);
497 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);
498 int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
499 			   u64 logical, u64 len);
500 unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
501 				    u64 logical);
502 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
503 			     u64 chunk_offset, u64 chunk_size);
504 int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);
505 struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
506 				       u64 logical, u64 length);
507 void btrfs_release_disk_super(struct btrfs_super_block *super);
508 
509 static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
510 				      int index)
511 {
512 	atomic_inc(dev->dev_stat_values + index);
513 	/*
514 	 * This memory barrier orders stores updating statistics before stores
515 	 * updating dev_stats_ccnt.
516 	 *
517 	 * It pairs with smp_rmb() in btrfs_run_dev_stats().
518 	 */
519 	smp_mb__before_atomic();
520 	atomic_inc(&dev->dev_stats_ccnt);
521 }
522 
523 static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
524 				      int index)
525 {
526 	return atomic_read(dev->dev_stat_values + index);
527 }
528 
529 static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
530 						int index)
531 {
532 	int ret;
533 
534 	ret = atomic_xchg(dev->dev_stat_values + index, 0);
535 	/*
536 	 * atomic_xchg implies a full memory barriers as per atomic_t.txt:
537 	 * - RMW operations that have a return value are fully ordered;
538 	 *
539 	 * This implicit memory barriers is paired with the smp_rmb in
540 	 * btrfs_run_dev_stats
541 	 */
542 	atomic_inc(&dev->dev_stats_ccnt);
543 	return ret;
544 }
545 
546 static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
547 				      int index, unsigned long val)
548 {
549 	atomic_set(dev->dev_stat_values + index, val);
550 	/*
551 	 * This memory barrier orders stores updating statistics before stores
552 	 * updating dev_stats_ccnt.
553 	 *
554 	 * It pairs with smp_rmb() in btrfs_run_dev_stats().
555 	 */
556 	smp_mb__before_atomic();
557 	atomic_inc(&dev->dev_stats_ccnt);
558 }
559 
560 /*
561  * Convert block group flags (BTRFS_BLOCK_GROUP_*) to btrfs_raid_types, which
562  * can be used as index to access btrfs_raid_array[].
563  */
564 static inline enum btrfs_raid_types btrfs_bg_flags_to_raid_index(u64 flags)
565 {
566 	if (flags & BTRFS_BLOCK_GROUP_RAID10)
567 		return BTRFS_RAID_RAID10;
568 	else if (flags & BTRFS_BLOCK_GROUP_RAID1)
569 		return BTRFS_RAID_RAID1;
570 	else if (flags & BTRFS_BLOCK_GROUP_RAID1C3)
571 		return BTRFS_RAID_RAID1C3;
572 	else if (flags & BTRFS_BLOCK_GROUP_RAID1C4)
573 		return BTRFS_RAID_RAID1C4;
574 	else if (flags & BTRFS_BLOCK_GROUP_DUP)
575 		return BTRFS_RAID_DUP;
576 	else if (flags & BTRFS_BLOCK_GROUP_RAID0)
577 		return BTRFS_RAID_RAID0;
578 	else if (flags & BTRFS_BLOCK_GROUP_RAID5)
579 		return BTRFS_RAID_RAID5;
580 	else if (flags & BTRFS_BLOCK_GROUP_RAID6)
581 		return BTRFS_RAID_RAID6;
582 
583 	return BTRFS_RAID_SINGLE; /* BTRFS_BLOCK_GROUP_SINGLE */
584 }
585 
586 void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
587 
588 struct list_head * __attribute_const__ btrfs_get_fs_uuids(void);
589 bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
590 					struct btrfs_device *failing_dev);
591 void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info,
592 			       struct block_device *bdev,
593 			       const char *device_path);
594 
595 int btrfs_bg_type_to_factor(u64 flags);
596 const char *btrfs_bg_type_to_raid_name(u64 flags);
597 int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
598 
599 #endif
600