volumes.h

  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/blk_types.h>
 10#include <linux/blkdev.h>
 11#include <linux/sizes.h>
 12#include <linux/atomic.h>
 13#include <linux/sort.h>
 14#include <linux/list.h>
 15#include <linux/mutex.h>
 16#include <linux/log2.h>
 17#include <linux/kobject.h>
 18#include <linux/refcount.h>
 19#include <linux/completion.h>
 20#include <linux/rbtree.h>
 21#include <uapi/linux/btrfs.h>
 22#include <uapi/linux/btrfs_tree.h>
 23#include "messages.h"
 24#include "extent-io-tree.h"
 25
 26struct block_device;
 27struct bdev_handle;
 28struct btrfs_fs_info;
 29struct btrfs_block_group;
 30struct btrfs_trans_handle;
 31struct btrfs_transaction;
 32struct btrfs_zoned_device_info;
 33
 34#define BTRFS_MAX_DATA_CHUNK_SIZE	(10ULL * SZ_1G)
 35
 36/*
 37 * Arbitrary maximum size of one discard request to limit potentially long time
 38 * spent in blkdev_issue_discard().
 39 */
 40#define BTRFS_MAX_DISCARD_CHUNK_SIZE	(SZ_1G)
 41
 42extern struct mutex uuid_mutex;
 43
 44#define BTRFS_STRIPE_LEN		SZ_64K
 45#define BTRFS_STRIPE_LEN_SHIFT		(16)
 46#define BTRFS_STRIPE_LEN_MASK		(BTRFS_STRIPE_LEN - 1)
 47
 48static_assert(ilog2(BTRFS_STRIPE_LEN) == BTRFS_STRIPE_LEN_SHIFT);
 49
 50/* Used by sanity check for btrfs_raid_types. */
 51#define const_ffs(n) (__builtin_ctzll(n) + 1)
 52
 53/*
 54 * The conversion from BTRFS_BLOCK_GROUP_* bits to btrfs_raid_type requires
 55 * RAID0 always to be the lowest profile bit.
 56 * Although it's part of on-disk format and should never change, do extra
 57 * compile-time sanity checks.
 58 */
 59static_assert(const_ffs(BTRFS_BLOCK_GROUP_RAID0) <
 60	      const_ffs(BTRFS_BLOCK_GROUP_PROFILE_MASK & ~BTRFS_BLOCK_GROUP_RAID0));
 61static_assert(ilog2(BTRFS_BLOCK_GROUP_RAID0) > ilog2(BTRFS_BLOCK_GROUP_TYPE_MASK));
 62
 63/* ilog2() can handle both constants and variables */
 64#define BTRFS_BG_FLAG_TO_INDEX(profile)					\
 65	ilog2((profile) >> (ilog2(BTRFS_BLOCK_GROUP_RAID0) - 1))
 66
 67enum btrfs_raid_types {
 68	/* SINGLE is the special one as it doesn't have on-disk bit. */
 69	BTRFS_RAID_SINGLE  = 0,
 70
 71	BTRFS_RAID_RAID0   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID0),
 72	BTRFS_RAID_RAID1   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1),
 73	BTRFS_RAID_DUP	   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_DUP),
 74	BTRFS_RAID_RAID10  = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID10),
 75	BTRFS_RAID_RAID5   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID5),
 76	BTRFS_RAID_RAID6   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID6),
 77	BTRFS_RAID_RAID1C3 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C3),
 78	BTRFS_RAID_RAID1C4 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C4),
 79
 80	BTRFS_NR_RAID_TYPES
 81};
 82
 83/*
 84 * Use sequence counter to get consistent device stat data on
 85 * 32-bit processors.
 86 */
 87#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 88#include <linux/seqlock.h>
 89#define __BTRFS_NEED_DEVICE_DATA_ORDERED
 90#define btrfs_device_data_ordered_init(device)	\
 91	seqcount_init(&device->data_seqcount)
 92#else
 93#define btrfs_device_data_ordered_init(device) do { } while (0)
 94#endif
 95
 96#define BTRFS_DEV_STATE_WRITEABLE	(0)
 97#define BTRFS_DEV_STATE_IN_FS_METADATA	(1)
 98#define BTRFS_DEV_STATE_MISSING		(2)
 99#define BTRFS_DEV_STATE_REPLACE_TGT	(3)
100#define BTRFS_DEV_STATE_FLUSH_SENT	(4)
101#define BTRFS_DEV_STATE_NO_READA	(5)
102
103/* Set when the device item is found in chunk tree, used to catch unexpected registered device. */
104#define BTRFS_DEV_STATE_ITEM_FOUND	(7)
105
106/* Special value encoding failure to write primary super block. */
107#define BTRFS_SUPER_PRIMARY_WRITE_ERROR		(INT_MAX / 2)
108
109struct btrfs_fs_devices;
110
111struct btrfs_device {
112	struct list_head dev_list; /* device_list_mutex */
113	struct list_head dev_alloc_list; /* chunk mutex */
114	struct list_head post_commit_list; /* chunk mutex */
115	struct btrfs_fs_devices *fs_devices;
116	struct btrfs_fs_info *fs_info;
117
118	/* Device path or NULL if missing. */
119	const char __rcu *name;
120
121	u64 generation;
122
123	struct file *bdev_file;
124	struct block_device *bdev;
125
126	struct btrfs_zoned_device_info *zone_info;
127
128	/*
129	 * Device's major-minor number. Must be set even if the device is not
130	 * opened (bdev == NULL), unless the device is missing.
131	 */
132	dev_t devt;
133	unsigned long dev_state;
134	blk_status_t last_flush_error;
135
136#ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
137	seqcount_t data_seqcount;
138#endif
139
140	/* the internal btrfs device id */
141	u64 devid;
142
143	/* size of the device in memory */
144	u64 total_bytes;
145
146	/* size of the device on disk */
147	u64 disk_total_bytes;
148
149	/* bytes used */
150	u64 bytes_used;
151
152	/* optimal io alignment for this device */
153	u32 io_align;
154
155	/* optimal io width for this device */
156	u32 io_width;
157	/* type and info about this device */
158	u64 type;
159
160	/*
161	 * Counter of super block write errors, values larger than
162	 * BTRFS_SUPER_PRIMARY_WRITE_ERROR encode primary super block write failure.
163	 */
164	atomic_t sb_write_errors;
165
166	/* minimal io size for this device */
167	u32 sector_size;
168
169	/* physical drive uuid (or lvm uuid) */
170	u8 uuid[BTRFS_UUID_SIZE];
171
172	/*
173	 * size of the device on the current transaction
174	 *
175	 * This variant is update when committing the transaction,
176	 * and protected by chunk mutex
177	 */
178	u64 commit_total_bytes;
179
180	/* bytes used on the current transaction */
181	u64 commit_bytes_used;
182
183	/* Bio used for flushing device barriers */
184	struct bio flush_bio;
185	struct completion flush_wait;
186
187	/* per-device scrub information */
188	struct scrub_ctx *scrub_ctx;
189
190	/* disk I/O failure stats. For detailed description refer to
191	 * enum btrfs_dev_stat_values in ioctl.h */
192	int dev_stats_valid;
193
194	/* Counter to record the change of device stats */
195	atomic_t dev_stats_ccnt;
196	atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
197
198	struct extent_io_tree alloc_state;
199
200	struct completion kobj_unregister;
201	/* For sysfs/FSID/devinfo/devid/ */
202	struct kobject devid_kobj;
203
204	/* Bandwidth limit for scrub, in bytes */
205	u64 scrub_speed_max;
206};
207
208/*
209 * Block group or device which contains an active swapfile. Used for preventing
210 * unsafe operations while a swapfile is active.
211 *
212 * These are sorted on (ptr, inode) (note that a block group or device can
213 * contain more than one swapfile). We compare the pointer values because we
214 * don't actually care what the object is, we just need a quick check whether
215 * the object exists in the rbtree.
216 */
217struct btrfs_swapfile_pin {
218	struct rb_node node;
219	void *ptr;
220	struct inode *inode;
221	/*
222	 * If true, ptr points to a struct btrfs_block_group. Otherwise, ptr
223	 * points to a struct btrfs_device.
224	 */
225	bool is_block_group;
226	/*
227	 * Only used when 'is_block_group' is true and it is the number of
228	 * extents used by a swapfile for this block group ('ptr' field).
229	 */
230	int bg_extent_count;
231};
232
233/*
234 * If we read those variants at the context of their own lock, we needn't
235 * use the following helpers, reading them directly is safe.
236 */
237#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
238#define BTRFS_DEVICE_GETSET_FUNCS(name)					\
239static inline u64							\
240btrfs_device_get_##name(const struct btrfs_device *dev)			\
241{									\
242	u64 size;							\
243	unsigned int seq;						\
244									\
245	do {								\
246		seq = read_seqcount_begin(&dev->data_seqcount);		\
247		size = dev->name;					\
248	} while (read_seqcount_retry(&dev->data_seqcount, seq));	\
249	return size;							\
250}									\
251									\
252static inline void							\
253btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
254{									\
255	preempt_disable();						\
256	write_seqcount_begin(&dev->data_seqcount);			\
257	dev->name = size;						\
258	write_seqcount_end(&dev->data_seqcount);			\
259	preempt_enable();						\
260}
261#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
262#define BTRFS_DEVICE_GETSET_FUNCS(name)					\
263static inline u64							\
264btrfs_device_get_##name(const struct btrfs_device *dev)			\
265{									\
266	u64 size;							\
267									\
268	preempt_disable();						\
269	size = dev->name;						\
270	preempt_enable();						\
271	return size;							\
272}									\
273									\
274static inline void							\
275btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
276{									\
277	preempt_disable();						\
278	dev->name = size;						\
279	preempt_enable();						\
280}
281#else
282#define BTRFS_DEVICE_GETSET_FUNCS(name)					\
283static inline u64							\
284btrfs_device_get_##name(const struct btrfs_device *dev)			\
285{									\
286	return dev->name;						\
287}									\
288									\
289static inline void							\
290btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
291{									\
292	dev->name = size;						\
293}
294#endif
295
296BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
297BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
298BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
299
300enum btrfs_chunk_allocation_policy {
301	BTRFS_CHUNK_ALLOC_REGULAR,
302	BTRFS_CHUNK_ALLOC_ZONED,
303};
304
305#define BTRFS_DEFAULT_RR_MIN_CONTIG_READ	(SZ_256K)
306/* Keep in sync with raid_attr table, current maximum is RAID1C4. */
307#define BTRFS_RAID1_MAX_MIRRORS			(4)
308/*
309 * Read policies for mirrored block group profiles, read picks the stripe based
310 * on these policies.
311 */
312enum btrfs_read_policy {
313	/* Use process PID to choose the stripe */
314	BTRFS_READ_POLICY_PID,
315#ifdef CONFIG_BTRFS_EXPERIMENTAL
316	/* Balancing RAID1 reads across all striped devices (round-robin). */
317	BTRFS_READ_POLICY_RR,
318	/* Read from a specific device. */
319	BTRFS_READ_POLICY_DEVID,
320#endif
321	BTRFS_NR_READ_POLICY,
322};
323
324#ifdef CONFIG_BTRFS_EXPERIMENTAL
325/*
326 * Checksum mode - offload it to workqueues or do it synchronously in
327 * btrfs_submit_chunk().
328 */
329enum btrfs_offload_csum_mode {
330	/*
331	 * Choose offloading checksum or do it synchronously automatically.
332	 * Do it synchronously if the checksum is fast, or offload to workqueues
333	 * otherwise.
334	 */
335	BTRFS_OFFLOAD_CSUM_AUTO,
336	/* Always offload checksum to workqueues. */
337	BTRFS_OFFLOAD_CSUM_FORCE_ON,
338	/* Never offload checksum to workqueues. */
339	BTRFS_OFFLOAD_CSUM_FORCE_OFF,
340};
341#endif
342
343struct btrfs_fs_devices {
344	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
345
346	/*
347	 * UUID written into the btree blocks:
348	 *
349	 * - If metadata_uuid != fsid then super block must have
350	 *   BTRFS_FEATURE_INCOMPAT_METADATA_UUID flag set.
351	 *
352	 * - Following shall be true at all times:
353	 *   - metadata_uuid == btrfs_header::fsid
354	 *   - metadata_uuid == btrfs_dev_item::fsid
355	 *
356	 * - Relations between fsid and metadata_uuid in sb and fs_devices:
357	 *   - Normal:
358	 *       fs_devices->fsid == fs_devices->metadata_uuid == sb->fsid
359	 *       sb->metadata_uuid == 0
360	 *
361	 *   - When the BTRFS_FEATURE_INCOMPAT_METADATA_UUID flag is set:
362	 *       fs_devices->fsid == sb->fsid
363	 *       fs_devices->metadata_uuid == sb->metadata_uuid
364	 *
365	 *   - When in-memory fs_devices->temp_fsid is true
366	 *	 fs_devices->fsid = random
367	 *	 fs_devices->metadata_uuid == sb->fsid
368	 */
369	u8 metadata_uuid[BTRFS_FSID_SIZE];
370
371	struct list_head fs_list;
372
373	/*
374	 * Number of devices under this fsid including missing and
375	 * replace-target device and excludes seed devices.
376	 */
377	u64 num_devices;
378
379	/*
380	 * The number of devices that successfully opened, including
381	 * replace-target, excludes seed devices.
382	 */
383	u64 open_devices;
384
385	/* The number of devices that are under the chunk allocation list. */
386	u64 rw_devices;
387
388	/* Count of missing devices under this fsid excluding seed device. */
389	u64 missing_devices;
390	u64 total_rw_bytes;
391
392	/*
393	 * Count of devices from btrfs_super_block::num_devices for this fsid,
394	 * which includes the seed device, excludes the transient replace-target
395	 * device.
396	 */
397	u64 total_devices;
398
399	/* Highest generation number of seen devices */
400	u64 latest_generation;
401
402	/*
403	 * The mount device or a device with highest generation after removal
404	 * or replace.
405	 */
406	struct btrfs_device *latest_dev;
407
408	/*
409	 * All of the devices in the filesystem, protected by a mutex so we can
410	 * safely walk it to write out the super blocks without worrying about
411	 * adding/removing by the multi-device code. Scrubbing super block can
412	 * kick off supers writing by holding this mutex lock.
413	 */
414	struct mutex device_list_mutex;
415
416	/* List of all devices, protected by device_list_mutex */
417	struct list_head devices;
418
419	/* Devices which can satisfy space allocation. Protected by * chunk_mutex. */
420	struct list_head alloc_list;
421
422	struct list_head seed_list;
423
424	/* Count fs-devices opened. */
425	int opened;
426
427	/*
428	 * Counter of the processes that are holding this fs_devices but not
429	 * yet opened.
430	 * This is for mounting handling, as we can only open the fs_devices
431	 * after a super block is created.  But we cannot take uuid_mutex
432	 * during sget_fc(), thus we have to hold the fs_devices (meaning it
433	 * cannot be released) until a super block is returned.
434	 */
435	int holding;
436
437	/* Set when we find or add a device that doesn't have the nonrot flag set. */
438	bool rotating;
439	/* Devices support TRIM/discard commands. */
440	bool discardable;
441	/* The filesystem is a seed filesystem. */
442	bool seeding;
443	/* The mount needs to use a randomly generated fsid. */
444	bool temp_fsid;
445	/* Enable/disable the filesystem stats tracking. */
446	bool collect_fs_stats;
447
448	struct btrfs_fs_info *fs_info;
449	/* sysfs kobjects */
450	struct kobject fsid_kobj;
451	struct kobject *devices_kobj;
452	struct kobject *devinfo_kobj;
453	struct completion kobj_unregister;
454
455	enum btrfs_chunk_allocation_policy chunk_alloc_policy;
456
457	/* Policy used to read the mirrored stripes. */
458	enum btrfs_read_policy read_policy;
459
460#ifdef CONFIG_BTRFS_EXPERIMENTAL
461	/*
462	 * Minimum contiguous reads before switching to next device, the unit
463	 * is one block/sectorsize.
464	 */
465	u32 rr_min_contig_read;
466
467	/* Device to be used for reading in case of RAID1. */
468	u64 read_devid;
469
470	/* Checksum mode - offload it or do it synchronously. */
471	enum btrfs_offload_csum_mode offload_csum_mode;
472#endif
473};
474
475#define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info)	\
476			- sizeof(struct btrfs_chunk))		\
477			/ sizeof(struct btrfs_stripe) + 1)
478
479#define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE	\
480				- 2 * sizeof(struct btrfs_disk_key)	\
481				- 2 * sizeof(struct btrfs_chunk))	\
482				/ sizeof(struct btrfs_stripe) + 1)
483
484struct btrfs_io_stripe {
485	struct btrfs_device *dev;
486	/* Block mapping. */
487	u64 physical;
488	bool rst_search_commit_root;
489	/* For the endio handler. */
490	struct btrfs_io_context *bioc;
491};
492
493struct btrfs_discard_stripe {
494	struct btrfs_device *dev;
495	u64 physical;
496	u64 length;
497};
498
499/*
500 * Context for IO submission for device stripe.
501 *
502 * - Track the unfinished mirrors for mirror based profiles
503 *   Mirror based profiles are SINGLE/DUP/RAID1/RAID10.
504 *
505 * - Contain the logical -> physical mapping info
506 *   Used by submit_stripe_bio() for mapping logical bio
507 *   into physical device address.
508 *
509 * - Contain device replace info
510 *   Used by handle_ops_on_dev_replace() to copy logical bios
511 *   into the new device.
512 *
513 * - Contain RAID56 full stripe logical bytenrs
514 */
515struct btrfs_io_context {
516	refcount_t refs;
517	struct btrfs_fs_info *fs_info;
518	/* Taken from struct btrfs_chunk_map::type. */
519	u64 map_type;
520	struct bio *orig_bio;
521	atomic_t error;
522	u16 max_errors;
523	bool use_rst;
524
525	u64 logical;
526	u64 size;
527	/* Raid stripe tree ordered entry. */
528	struct list_head rst_ordered_entry;
529
530	/*
531	 * The total number of stripes, including the extra duplicated
532	 * stripe for replace.
533	 */
534	u16 num_stripes;
535
536	/*
537	 * The mirror_num of this bioc.
538	 *
539	 * This is for reads which use 0 as mirror_num, thus we should return a
540	 * valid mirror_num (>0) for the reader.
541	 */
542	u16 mirror_num;
543
544	/*
545	 * The following two members are for dev-replace case only.
546	 *
547	 * @replace_nr_stripes:	Number of duplicated stripes which need to be
548	 *			written to replace target.
549	 *			Should be <= 2 (2 for DUP, otherwise <= 1).
550	 * @replace_stripe_src:	The array indicates where the duplicated stripes
551	 *			are from.
552	 *
553	 * The @replace_stripe_src[] array is mostly for RAID56 cases.
554	 * As non-RAID56 stripes share the same contents of the mapped range,
555	 * thus no need to bother where the duplicated ones are from.
556	 *
557	 * But for RAID56 case, all stripes contain different contents, thus
558	 * we need a way to know the mapping.
559	 *
560	 * There is an example for the two members, using a RAID5 write:
561	 *
562	 *   num_stripes:	4 (3 + 1 duplicated write)
563	 *   stripes[0]:	dev = devid 1, physical = X
564	 *   stripes[1]:	dev = devid 2, physical = Y
565	 *   stripes[2]:	dev = devid 3, physical = Z
566	 *   stripes[3]:	dev = devid 0, physical = Y
567	 *
568	 * replace_nr_stripes = 1
569	 * replace_stripe_src = 1	<- Means stripes[1] is involved in replace.
570	 *				   The duplicated stripe index would be
571	 *				   (@num_stripes - 1).
572	 *
573	 * Note, that we can still have cases replace_nr_stripes = 2 for DUP.
574	 * In that case, all stripes share the same content, thus we don't
575	 * need to bother @replace_stripe_src value at all.
576	 */
577	u16 replace_nr_stripes;
578	s16 replace_stripe_src;
579	/*
580	 * Logical bytenr of the full stripe start, only for RAID56 cases.
581	 *
582	 * When this value is set to other than (u64)-1, the stripes[] should
583	 * follow this pattern:
584	 *
585	 * (real_stripes = num_stripes - replace_nr_stripes)
586	 * (data_stripes = (is_raid6) ? (real_stripes - 2) : (real_stripes - 1))
587	 *
588	 * stripes[0]:			The first data stripe
589	 * stripes[1]:			The second data stripe
590	 * ...
591	 * stripes[data_stripes - 1]:	The last data stripe
592	 * stripes[data_stripes]:	The P stripe
593	 * stripes[data_stripes + 1]:	The Q stripe (only for RAID6).
594	 */
595	u64 full_stripe_logical;
596	struct btrfs_io_stripe stripes[];
597};
598
599struct btrfs_device_info {
600	struct btrfs_device *dev;
601	u64 dev_offset;
602	u64 max_avail;
603	u64 total_avail;
604};
605
606struct btrfs_raid_attr {
607	u8 sub_stripes;		/* sub_stripes info for map */
608	u8 dev_stripes;		/* stripes per dev */
609	u8 devs_max;		/* max devs to use */
610	u8 devs_min;		/* min devs needed */
611	u8 tolerated_failures;	/* max tolerated fail devs */
612	u8 devs_increment;	/* ndevs has to be a multiple of this */
613	u8 ncopies;		/* how many copies to data has */
614	u8 nparity;		/* number of stripes worth of bytes to store
615				 * parity information */
616	u8 mindev_error;	/* error code if min devs requisite is unmet */
617	const char raid_name[8]; /* name of the raid */
618	u64 bg_flag;		/* block group flag of the raid */
619};
620
621extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
622
623struct btrfs_chunk_map {
624	struct rb_node rb_node;
625	/* For mount time dev extent verification. */
626	int verified_stripes;
627	refcount_t refs;
628	u64 start;
629	u64 chunk_len;
630	u64 stripe_size;
631	u64 type;
632	int io_align;
633	int io_width;
634	int num_stripes;
635	int sub_stripes;
636	struct btrfs_io_stripe stripes[];
637};
638
639#define btrfs_chunk_map_size(n) (sizeof(struct btrfs_chunk_map) + \
640				 (sizeof(struct btrfs_io_stripe) * (n)))
641
642static inline void btrfs_free_chunk_map(struct btrfs_chunk_map *map)
643{
644	if (map && refcount_dec_and_test(&map->refs)) {
645		ASSERT(RB_EMPTY_NODE(&map->rb_node));
646		kfree(map);
647	}
648}
649
650struct btrfs_balance_control {
651	struct btrfs_balance_args data;
652	struct btrfs_balance_args meta;
653	struct btrfs_balance_args sys;
654
655	u64 flags;
656
657	struct btrfs_balance_progress stat;
658};
659
660/*
661 * Search for a given device by the set parameters
662 */
663struct btrfs_dev_lookup_args {
664	u64 devid;
665	u8 *uuid;
666	u8 *fsid;
667	/*
668	 * If devt is specified, all other members will be ignored as it is
669	 * enough to uniquely locate a device.
670	 */
671	dev_t devt;
672	bool missing;
673};
674
675/* We have to initialize to -1 because BTRFS_DEV_REPLACE_DEVID is 0 */
676#define BTRFS_DEV_LOOKUP_ARGS_INIT { .devid = (u64)-1 }
677
678#define BTRFS_DEV_LOOKUP_ARGS(name) \
679	struct btrfs_dev_lookup_args name = BTRFS_DEV_LOOKUP_ARGS_INIT
680
681enum btrfs_map_op {
682	BTRFS_MAP_READ,
683	BTRFS_MAP_WRITE,
684	BTRFS_MAP_GET_READ_MIRRORS,
685};
686
687static inline enum btrfs_map_op btrfs_op(const struct bio *bio)
688{
689	switch (bio_op(bio)) {
690	case REQ_OP_WRITE:
691	case REQ_OP_ZONE_APPEND:
692		return BTRFS_MAP_WRITE;
693	default:
694		WARN_ON_ONCE(1);
695		fallthrough;
696	case REQ_OP_READ:
697		return BTRFS_MAP_READ;
698	}
699}
700
701static inline unsigned long btrfs_chunk_item_size(int num_stripes)
702{
703	ASSERT(num_stripes);
704	return sizeof(struct btrfs_chunk) +
705		sizeof(struct btrfs_stripe) * (num_stripes - 1);
706}
707
708/*
709 * Do the type safe conversion from stripe_nr to offset inside the chunk.
710 *
711 * @stripe_nr is u32, with left shift it can overflow u32 for chunks larger
712 * than 4G.  This does the proper type cast to avoid overflow.
713 */
714static inline u64 btrfs_stripe_nr_to_offset(u32 stripe_nr)
715{
716	return (u64)stripe_nr << BTRFS_STRIPE_LEN_SHIFT;
717}
718
719void btrfs_get_bioc(struct btrfs_io_context *bioc);
720void btrfs_put_bioc(struct btrfs_io_context *bioc);
721int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
722		    u64 logical, u64 *length,
723		    struct btrfs_io_context **bioc_ret,
724		    struct btrfs_io_stripe *smap, int *mirror_num_ret);
725int btrfs_map_repair_block(struct btrfs_fs_info *fs_info,
726			   struct btrfs_io_stripe *smap, u64 logical,
727			   u32 length, int mirror_num);
728struct btrfs_discard_stripe *btrfs_map_discard(struct btrfs_fs_info *fs_info,
729					       u64 logical, u64 *length_ret,
730					       u32 *num_stripes);
731int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
732int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
733struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans,
734					     struct btrfs_space_info *space_info,
735					     u64 type);
736void btrfs_mapping_tree_free(struct btrfs_fs_info *fs_info);
737int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
738		       blk_mode_t flags, void *holder);
739struct btrfs_device *btrfs_scan_one_device(const char *path, bool mount_arg_dev);
740int btrfs_forget_devices(dev_t devt);
741void btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
742void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices);
743void btrfs_assign_next_active_device(struct btrfs_device *device,
744				     struct btrfs_device *this_dev);
745struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
746						  u64 devid,
747						  const char *devpath);
748int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
749				 struct btrfs_dev_lookup_args *args,
750				 const char *path);
751struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
752					const u64 *devid, const u8 *uuid,
753					const char *path);
754void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args);
755int btrfs_rm_device(struct btrfs_fs_info *fs_info,
756		    struct btrfs_dev_lookup_args *args,
757		    struct file **bdev_file);
758void __exit btrfs_cleanup_fs_uuids(void);
759int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
760int btrfs_grow_device(struct btrfs_trans_handle *trans,
761		      struct btrfs_device *device, u64 new_size);
762struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices,
763				       const struct btrfs_dev_lookup_args *args);
764int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
765int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
766int btrfs_balance(struct btrfs_fs_info *fs_info,
767		  struct btrfs_balance_control *bctl,
768		  struct btrfs_ioctl_balance_args *bargs);
769void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
770int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
771int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
772int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
773int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset,
774			 bool verbose);
775int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
776bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset);
777void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
778int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
779			struct btrfs_ioctl_get_dev_stats *stats);
780int btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
781int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
782int btrfs_run_dev_stats(struct btrfs_trans_handle *trans);
783void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);
784void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);
785void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);
786unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
787				    u64 logical);
788u64 btrfs_calc_stripe_length(const struct btrfs_chunk_map *map);
789int btrfs_nr_parity_stripes(u64 type);
790int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans,
791				     struct btrfs_block_group *bg);
792int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);
793
794#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
795struct btrfs_chunk_map *btrfs_alloc_chunk_map(int num_stripes, gfp_t gfp);
796int btrfs_add_chunk_map(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map);
797#endif
798
799struct btrfs_chunk_map *btrfs_find_chunk_map(struct btrfs_fs_info *fs_info,
800					     u64 logical, u64 length);
801struct btrfs_chunk_map *btrfs_find_chunk_map_nolock(struct btrfs_fs_info *fs_info,
802						    u64 logical, u64 length);
803struct btrfs_chunk_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
804					    u64 logical, u64 length);
805void btrfs_remove_chunk_map(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map);
806struct btrfs_super_block *btrfs_read_disk_super(struct block_device *bdev,
807						int copy_num, bool drop_cache);
808void btrfs_release_disk_super(struct btrfs_super_block *super);
809
810static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
811				      int index)
812{
813	atomic_inc(dev->dev_stat_values + index);
814	/*
815	 * This memory barrier orders stores updating statistics before stores
816	 * updating dev_stats_ccnt.
817	 *
818	 * It pairs with smp_rmb() in btrfs_run_dev_stats().
819	 */
820	smp_mb__before_atomic();
821	atomic_inc(&dev->dev_stats_ccnt);
822}
823
824static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
825				      int index)
826{
827	return atomic_read(dev->dev_stat_values + index);
828}
829
830static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
831						int index)
832{
833	int ret;
834
835	ret = atomic_xchg(dev->dev_stat_values + index, 0);
836	/*
837	 * atomic_xchg implies a full memory barriers as per atomic_t.txt:
838	 * - RMW operations that have a return value are fully ordered;
839	 *
840	 * This implicit memory barriers is paired with the smp_rmb in
841	 * btrfs_run_dev_stats
842	 */
843	atomic_inc(&dev->dev_stats_ccnt);
844	return ret;
845}
846
847static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
848				      int index, unsigned long val)
849{
850	atomic_set(dev->dev_stat_values + index, val);
851	/*
852	 * This memory barrier orders stores updating statistics before stores
853	 * updating dev_stats_ccnt.
854	 *
855	 * It pairs with smp_rmb() in btrfs_run_dev_stats().
856	 */
857	smp_mb__before_atomic();
858	atomic_inc(&dev->dev_stats_ccnt);
859}
860
861static inline const char *btrfs_dev_name(const struct btrfs_device *device)
862{
863	if (!device || test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state))
864		return "<missing disk>";
865	else
866		return rcu_dereference(device->name);
867}
868
869static inline void btrfs_warn_unknown_chunk_allocation(enum btrfs_chunk_allocation_policy pol)
870{
871	WARN_ONCE(1, "unknown allocation policy %d, fallback to regular", pol);
872}
873
874static inline void btrfs_fs_devices_inc_holding(struct btrfs_fs_devices *fs_devices)
875{
876	lockdep_assert_held(&uuid_mutex);
877	ASSERT(fs_devices->holding >= 0);
878	fs_devices->holding++;
879}
880
881static inline void btrfs_fs_devices_dec_holding(struct btrfs_fs_devices *fs_devices)
882{
883	lockdep_assert_held(&uuid_mutex);
884	ASSERT(fs_devices->holding > 0);
885	fs_devices->holding--;
886}
887
888void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
889
890struct list_head * __attribute_const__ btrfs_get_fs_uuids(void);
891bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
892					struct btrfs_device *failing_dev);
893void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info, struct btrfs_device *device);
894
895enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags);
896int btrfs_bg_type_to_factor(u64 flags);
897const char *btrfs_bg_type_to_raid_name(u64 flags);
898int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
899bool btrfs_verify_dev_items(const struct btrfs_fs_info *fs_info);
900bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical);
901
902bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr);
903const u8 *btrfs_sb_fsid_ptr(const struct btrfs_super_block *sb);
904
905#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
906struct btrfs_io_context *alloc_btrfs_io_context(struct btrfs_fs_info *fs_info,
907						u64 logical, u16 total_stripes);
908#endif
909
910#endif