xref: /openbmc/linux/fs/btrfs/volumes.h (revision 162736b0)
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 
18 extern 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  */
31 static_assert(const_ffs(BTRFS_BLOCK_GROUP_RAID0) <
32 	      const_ffs(BTRFS_BLOCK_GROUP_PROFILE_MASK & ~BTRFS_BLOCK_GROUP_RAID0));
33 static_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 
40 enum 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 
56 struct 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 
91 struct btrfs_zoned_device_info;
92 
93 struct 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  */
194 struct 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)					\
216 static inline u64							\
217 btrfs_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 									\
229 static inline void							\
230 btrfs_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)					\
240 static inline u64							\
241 btrfs_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 									\
251 static inline void							\
252 btrfs_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)					\
260 static inline u64							\
261 btrfs_device_get_##name(const struct btrfs_device *dev)			\
262 {									\
263 	return dev->name;						\
264 }									\
265 									\
266 static inline void							\
267 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
268 {									\
269 	dev->name = size;						\
270 }
271 #endif
272 
273 BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
274 BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
275 BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
276 
277 enum 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  */
286 enum btrfs_read_policy {
287 	/* Use process PID to choose the stripe */
288 	BTRFS_READ_POLICY_PID,
289 	BTRFS_NR_READ_POLICY,
290 };
291 
292 struct 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 
384 struct 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 
394 struct 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  */
416 struct 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 
436 struct btrfs_device_info {
437 	struct btrfs_device *dev;
438 	u64 dev_offset;
439 	u64 max_avail;
440 	u64 total_avail;
441 };
442 
443 struct 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 
458 extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
459 
460 struct 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 
474 struct btrfs_balance_args;
475 struct btrfs_balance_progress;
476 struct 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  */
489 struct 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 
502 enum btrfs_map_op {
503 	BTRFS_MAP_READ,
504 	BTRFS_MAP_WRITE,
505 	BTRFS_MAP_DISCARD,
506 	BTRFS_MAP_GET_READ_MIRRORS,
507 };
508 
509 static 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 
525 static 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 
532 void btrfs_get_bioc(struct btrfs_io_context *bioc);
533 void btrfs_put_bioc(struct btrfs_io_context *bioc);
534 int 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);
537 int 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);
540 int __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);
545 struct btrfs_discard_stripe *btrfs_map_discard(struct btrfs_fs_info *fs_info,
546 					       u64 logical, u64 *length_ret,
547 					       u32 *num_stripes);
548 int 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);
551 int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
552 int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
553 struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans,
554 					    u64 type);
555 void btrfs_mapping_tree_free(struct extent_map_tree *tree);
556 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
557 		       fmode_t flags, void *holder);
558 struct btrfs_device *btrfs_scan_one_device(const char *path,
559 					   fmode_t flags, void *holder);
560 int btrfs_forget_devices(dev_t devt);
561 void btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
562 void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices);
563 void btrfs_assign_next_active_device(struct btrfs_device *device,
564 				     struct btrfs_device *this_dev);
565 struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
566 						  u64 devid,
567 						  const char *devpath);
568 int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
569 				 struct btrfs_dev_lookup_args *args,
570 				 const char *path);
571 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
572 					const u64 *devid, const u8 *uuid,
573 					const char *path);
574 void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args);
575 void btrfs_free_device(struct btrfs_device *device);
576 int btrfs_rm_device(struct btrfs_fs_info *fs_info,
577 		    struct btrfs_dev_lookup_args *args,
578 		    struct block_device **bdev, fmode_t *mode);
579 void __exit btrfs_cleanup_fs_uuids(void);
580 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
581 int btrfs_grow_device(struct btrfs_trans_handle *trans,
582 		      struct btrfs_device *device, u64 new_size);
583 struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices,
584 				       const struct btrfs_dev_lookup_args *args);
585 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
586 int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
587 int btrfs_balance(struct btrfs_fs_info *fs_info,
588 		  struct btrfs_balance_control *bctl,
589 		  struct btrfs_ioctl_balance_args *bargs);
590 void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
591 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
592 int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
593 int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
594 int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset);
595 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
596 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
597 int btrfs_uuid_scan_kthread(void *data);
598 bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset);
599 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
600 			 u64 *start, u64 *max_avail);
601 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
602 int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
603 			struct btrfs_ioctl_get_dev_stats *stats);
604 int btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
605 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
606 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans);
607 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);
608 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);
609 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);
610 int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
611 			   u64 logical, u64 len);
612 unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
613 				    u64 logical);
614 u64 btrfs_calc_stripe_length(const struct extent_map *em);
615 int btrfs_nr_parity_stripes(u64 type);
616 int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans,
617 				     struct btrfs_block_group *bg);
618 int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);
619 struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
620 				       u64 logical, u64 length);
621 void btrfs_release_disk_super(struct btrfs_super_block *super);
622 
623 static 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 
637 static 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 
643 static 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 
660 static 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 
674 static 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 
682 void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
683 
684 struct list_head * __attribute_const__ btrfs_get_fs_uuids(void);
685 bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
686 					struct btrfs_device *failing_dev);
687 void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info,
688 			       struct block_device *bdev,
689 			       const char *device_path);
690 
691 enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags);
692 int btrfs_bg_type_to_factor(u64 flags);
693 const char *btrfs_bg_type_to_raid_name(u64 flags);
694 int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
695 bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical);
696 
697 bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr);
698 
699 #endif
700