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v6.13.7
  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/sizes.h>
 11#include <linux/atomic.h>
 12#include <linux/sort.h>
 13#include <linux/list.h>
 14#include <linux/mutex.h>
 15#include <linux/log2.h>
 16#include <linux/kobject.h>
 17#include <linux/refcount.h>
 18#include <linux/completion.h>
 19#include <linux/rbtree.h>
 20#include <uapi/linux/btrfs.h>
 21#include "messages.h"
 22#include "rcu-string.h"
 23
 24struct block_device;
 25struct bdev_handle;
 26struct btrfs_fs_info;
 27struct btrfs_block_group;
 28struct btrfs_trans_handle;
 29struct btrfs_zoned_device_info;
 30
 31#define BTRFS_MAX_DATA_CHUNK_SIZE	(10ULL * SZ_1G)
 32
 33/*
 34 * Arbitratry maximum size of one discard request to limit potentially long time
 35 * spent in blkdev_issue_discard().
 36 */
 37#define BTRFS_MAX_DISCARD_CHUNK_SIZE	(SZ_1G)
 38
 39extern struct mutex uuid_mutex;
 40
 41#define BTRFS_STRIPE_LEN		SZ_64K
 42#define BTRFS_STRIPE_LEN_SHIFT		(16)
 43#define BTRFS_STRIPE_LEN_MASK		(BTRFS_STRIPE_LEN - 1)
 44
 45static_assert(const_ilog2(BTRFS_STRIPE_LEN) == BTRFS_STRIPE_LEN_SHIFT);
 46
 47/* Used by sanity check for btrfs_raid_types. */
 48#define const_ffs(n) (__builtin_ctzll(n) + 1)
 49
 50/*
 51 * The conversion from BTRFS_BLOCK_GROUP_* bits to btrfs_raid_type requires
 52 * RAID0 always to be the lowest profile bit.
 53 * Although it's part of on-disk format and should never change, do extra
 54 * compile-time sanity checks.
 55 */
 56static_assert(const_ffs(BTRFS_BLOCK_GROUP_RAID0) <
 57	      const_ffs(BTRFS_BLOCK_GROUP_PROFILE_MASK & ~BTRFS_BLOCK_GROUP_RAID0));
 58static_assert(const_ilog2(BTRFS_BLOCK_GROUP_RAID0) >
 59	      ilog2(BTRFS_BLOCK_GROUP_TYPE_MASK));
 60
 61/* ilog2() can handle both constants and variables */
 62#define BTRFS_BG_FLAG_TO_INDEX(profile)					\
 63	ilog2((profile) >> (ilog2(BTRFS_BLOCK_GROUP_RAID0) - 1))
 64
 65enum btrfs_raid_types {
 66	/* SINGLE is the special one as it doesn't have on-disk bit. */
 67	BTRFS_RAID_SINGLE  = 0,
 68
 69	BTRFS_RAID_RAID0   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID0),
 70	BTRFS_RAID_RAID1   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1),
 71	BTRFS_RAID_DUP	   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_DUP),
 72	BTRFS_RAID_RAID10  = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID10),
 73	BTRFS_RAID_RAID5   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID5),
 74	BTRFS_RAID_RAID6   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID6),
 75	BTRFS_RAID_RAID1C3 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C3),
 76	BTRFS_RAID_RAID1C4 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C4),
 77
 78	BTRFS_NR_RAID_TYPES
 79};
 80
 81/*
 82 * Use sequence counter to get consistent device stat data on
 83 * 32-bit processors.
 84 */
 85#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 86#include <linux/seqlock.h>
 87#define __BTRFS_NEED_DEVICE_DATA_ORDERED
 88#define btrfs_device_data_ordered_init(device)	\
 89	seqcount_init(&device->data_seqcount)
 90#else
 91#define btrfs_device_data_ordered_init(device) do { } while (0)
 92#endif
 93
 94#define BTRFS_DEV_STATE_WRITEABLE	(0)
 95#define BTRFS_DEV_STATE_IN_FS_METADATA	(1)
 96#define BTRFS_DEV_STATE_MISSING		(2)
 97#define BTRFS_DEV_STATE_REPLACE_TGT	(3)
 98#define BTRFS_DEV_STATE_FLUSH_SENT	(4)
 99#define BTRFS_DEV_STATE_NO_READA	(5)
100
101/* Special value encoding failure to write primary super block. */
102#define BTRFS_SUPER_PRIMARY_WRITE_ERROR		(INT_MAX / 2)
103
104struct btrfs_fs_devices;
105
106struct btrfs_device {
107	struct list_head dev_list; /* device_list_mutex */
108	struct list_head dev_alloc_list; /* chunk mutex */
109	struct list_head post_commit_list; /* chunk mutex */
110	struct btrfs_fs_devices *fs_devices;
111	struct btrfs_fs_info *fs_info;
112
113	struct rcu_string __rcu *name;
 
 
 
114
 
115	u64 generation;
116
117	struct file *bdev_file;
 
 
 
 
 
 
118	struct block_device *bdev;
119
120	struct btrfs_zoned_device_info *zone_info;
 
121
122	/*
123	 * Device's major-minor number. Must be set even if the device is not
124	 * opened (bdev == NULL), unless the device is missing.
125	 */
126	dev_t devt;
127	unsigned long dev_state;
128	blk_status_t last_flush_error;
129
130#ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
131	seqcount_t data_seqcount;
132#endif
133
134	/* the internal btrfs device id */
135	u64 devid;
136
137	/* size of the device in memory */
138	u64 total_bytes;
139
140	/* size of the device on disk */
141	u64 disk_total_bytes;
142
143	/* bytes used */
144	u64 bytes_used;
145
146	/* optimal io alignment for this device */
147	u32 io_align;
148
149	/* optimal io width for this device */
150	u32 io_width;
151	/* type and info about this device */
152	u64 type;
153
154	/*
155	 * Counter of super block write errors, values larger than
156	 * BTRFS_SUPER_PRIMARY_WRITE_ERROR encode primary super block write failure.
157	 */
158	atomic_t sb_write_errors;
159
160	/* minimal io size for this device */
161	u32 sector_size;
162
 
 
 
163	/* physical drive uuid (or lvm uuid) */
164	u8 uuid[BTRFS_UUID_SIZE];
165
166	/*
167	 * size of the device on the current transaction
168	 *
169	 * This variant is update when committing the transaction,
170	 * and protected by chunk mutex
171	 */
172	u64 commit_total_bytes;
173
174	/* bytes used on the current transaction */
175	u64 commit_bytes_used;
176
177	/* Bio used for flushing device barriers */
178	struct bio flush_bio;
179	struct completion flush_wait;
180
181	/* per-device scrub information */
182	struct scrub_ctx *scrub_ctx;
183
184	/* disk I/O failure stats. For detailed description refer to
185	 * enum btrfs_dev_stat_values in ioctl.h */
186	int dev_stats_valid;
187
188	/* Counter to record the change of device stats */
189	atomic_t dev_stats_ccnt;
190	atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
191
192	struct extent_io_tree alloc_state;
193
194	struct completion kobj_unregister;
195	/* For sysfs/FSID/devinfo/devid/ */
196	struct kobject devid_kobj;
197
198	/* Bandwidth limit for scrub, in bytes */
199	u64 scrub_speed_max;
200};
201
202/*
203 * Block group or device which contains an active swapfile. Used for preventing
204 * unsafe operations while a swapfile is active.
205 *
206 * These are sorted on (ptr, inode) (note that a block group or device can
207 * contain more than one swapfile). We compare the pointer values because we
208 * don't actually care what the object is, we just need a quick check whether
209 * the object exists in the rbtree.
210 */
211struct btrfs_swapfile_pin {
212	struct rb_node node;
213	void *ptr;
214	struct inode *inode;
215	/*
216	 * If true, ptr points to a struct btrfs_block_group. Otherwise, ptr
217	 * points to a struct btrfs_device.
218	 */
219	bool is_block_group;
220	/*
221	 * Only used when 'is_block_group' is true and it is the number of
222	 * extents used by a swapfile for this block group ('ptr' field).
223	 */
224	int bg_extent_count;
225};
226
227/*
228 * If we read those variants at the context of their own lock, we needn't
229 * use the following helpers, reading them directly is safe.
230 */
231#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
232#define BTRFS_DEVICE_GETSET_FUNCS(name)					\
233static inline u64							\
234btrfs_device_get_##name(const struct btrfs_device *dev)			\
235{									\
236	u64 size;							\
237	unsigned int seq;						\
238									\
239	do {								\
240		seq = read_seqcount_begin(&dev->data_seqcount);		\
241		size = dev->name;					\
242	} while (read_seqcount_retry(&dev->data_seqcount, seq));	\
243	return size;							\
244}									\
245									\
246static inline void							\
247btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
248{									\
249	preempt_disable();						\
250	write_seqcount_begin(&dev->data_seqcount);			\
251	dev->name = size;						\
252	write_seqcount_end(&dev->data_seqcount);			\
253	preempt_enable();						\
254}
255#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
256#define BTRFS_DEVICE_GETSET_FUNCS(name)					\
257static inline u64							\
258btrfs_device_get_##name(const struct btrfs_device *dev)			\
259{									\
260	u64 size;							\
261									\
262	preempt_disable();						\
263	size = dev->name;						\
264	preempt_enable();						\
265	return size;							\
266}									\
267									\
268static inline void							\
269btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
270{									\
271	preempt_disable();						\
272	dev->name = size;						\
273	preempt_enable();						\
274}
275#else
276#define BTRFS_DEVICE_GETSET_FUNCS(name)					\
277static inline u64							\
278btrfs_device_get_##name(const struct btrfs_device *dev)			\
279{									\
280	return dev->name;						\
281}									\
282									\
283static inline void							\
284btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
285{									\
286	dev->name = size;						\
287}
288#endif
289
290BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
291BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
292BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
293
294enum btrfs_chunk_allocation_policy {
295	BTRFS_CHUNK_ALLOC_REGULAR,
296	BTRFS_CHUNK_ALLOC_ZONED,
297};
298
299/*
300 * Read policies for mirrored block group profiles, read picks the stripe based
301 * on these policies.
302 */
303enum btrfs_read_policy {
304	/* Use process PID to choose the stripe */
305	BTRFS_READ_POLICY_PID,
306	BTRFS_NR_READ_POLICY,
307};
308
309#ifdef CONFIG_BTRFS_EXPERIMENTAL
310/*
311 * Checksum mode - offload it to workqueues or do it synchronously in
312 * btrfs_submit_chunk().
313 */
314enum btrfs_offload_csum_mode {
315	/*
316	 * Choose offloading checksum or do it synchronously automatically.
317	 * Do it synchronously if the checksum is fast, or offload to workqueues
318	 * otherwise.
319	 */
320	BTRFS_OFFLOAD_CSUM_AUTO,
321	/* Always offload checksum to workqueues. */
322	BTRFS_OFFLOAD_CSUM_FORCE_ON,
323	/* Never offload checksum to workqueues. */
324	BTRFS_OFFLOAD_CSUM_FORCE_OFF,
325};
326#endif
327
328struct btrfs_fs_devices {
329	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
330
331	/*
332	 * UUID written into the btree blocks:
333	 *
334	 * - If metadata_uuid != fsid then super block must have
335	 *   BTRFS_FEATURE_INCOMPAT_METADATA_UUID flag set.
336	 *
337	 * - Following shall be true at all times:
338	 *   - metadata_uuid == btrfs_header::fsid
339	 *   - metadata_uuid == btrfs_dev_item::fsid
340	 *
341	 * - Relations between fsid and metadata_uuid in sb and fs_devices:
342	 *   - Normal:
343	 *       fs_devices->fsid == fs_devices->metadata_uuid == sb->fsid
344	 *       sb->metadata_uuid == 0
345	 *
346	 *   - When the BTRFS_FEATURE_INCOMPAT_METADATA_UUID flag is set:
347	 *       fs_devices->fsid == sb->fsid
348	 *       fs_devices->metadata_uuid == sb->metadata_uuid
349	 *
350	 *   - When in-memory fs_devices->temp_fsid is true
351	 *	 fs_devices->fsid = random
352	 *	 fs_devices->metadata_uuid == sb->fsid
353	 */
354	u8 metadata_uuid[BTRFS_FSID_SIZE];
355
356	struct list_head fs_list;
357
358	/*
359	 * Number of devices under this fsid including missing and
360	 * replace-target device and excludes seed devices.
361	 */
362	u64 num_devices;
363
364	/*
365	 * The number of devices that successfully opened, including
366	 * replace-target, excludes seed devices.
367	 */
368	u64 open_devices;
369
370	/* The number of devices that are under the chunk allocation list. */
371	u64 rw_devices;
372
373	/* Count of missing devices under this fsid excluding seed device. */
374	u64 missing_devices;
375	u64 total_rw_bytes;
 
 
376
377	/*
378	 * Count of devices from btrfs_super_block::num_devices for this fsid,
379	 * which includes the seed device, excludes the transient replace-target
380	 * device.
381	 */
382	u64 total_devices;
383
384	/* Highest generation number of seen devices */
385	u64 latest_generation;
386
387	/*
388	 * The mount device or a device with highest generation after removal
389	 * or replace.
390	 */
391	struct btrfs_device *latest_dev;
392
393	/*
394	 * All of the devices in the filesystem, protected by a mutex so we can
395	 * safely walk it to write out the super blocks without worrying about
396	 * adding/removing by the multi-device code. Scrubbing super block can
397	 * kick off supers writing by holding this mutex lock.
398	 */
399	struct mutex device_list_mutex;
400
401	/* List of all devices, protected by device_list_mutex */
402	struct list_head devices;
403
404	/* Devices which can satisfy space allocation. Protected by * chunk_mutex. */
405	struct list_head alloc_list;
 
406
407	struct list_head seed_list;
 
408
409	/* Count fs-devices opened. */
410	int opened;
411
412	/* Set when we find or add a device that doesn't have the nonrot flag set. */
413	bool rotating;
414	/* Devices support TRIM/discard commands. */
415	bool discardable;
416	/* The filesystem is a seed filesystem. */
417	bool seeding;
418	/* The mount needs to use a randomly generated fsid. */
419	bool temp_fsid;
420
421	struct btrfs_fs_info *fs_info;
422	/* sysfs kobjects */
423	struct kobject fsid_kobj;
424	struct kobject *devices_kobj;
425	struct kobject *devinfo_kobj;
426	struct completion kobj_unregister;
427
428	enum btrfs_chunk_allocation_policy chunk_alloc_policy;
429
430	/* Policy used to read the mirrored stripes. */
431	enum btrfs_read_policy read_policy;
432
433#ifdef CONFIG_BTRFS_EXPERIMENTAL
434	/* Checksum mode - offload it or do it synchronously. */
435	enum btrfs_offload_csum_mode offload_csum_mode;
436#endif
437};
438
439#define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info)	\
440			- sizeof(struct btrfs_chunk))		\
441			/ sizeof(struct btrfs_stripe) + 1)
442
443#define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE	\
444				- 2 * sizeof(struct btrfs_disk_key)	\
445				- 2 * sizeof(struct btrfs_chunk))	\
446				/ sizeof(struct btrfs_stripe) + 1)
447
448struct btrfs_io_stripe {
449	struct btrfs_device *dev;
450	/* Block mapping. */
451	u64 physical;
452	u64 length;
453	bool rst_search_commit_root;
454	/* For the endio handler. */
455	struct btrfs_io_context *bioc;
456};
457
458struct btrfs_discard_stripe {
459	struct btrfs_device *dev;
460	u64 physical;
461	u64 length;
462};
463
464/*
465 * Context for IO subsmission for device stripe.
466 *
467 * - Track the unfinished mirrors for mirror based profiles
468 *   Mirror based profiles are SINGLE/DUP/RAID1/RAID10.
469 *
470 * - Contain the logical -> physical mapping info
471 *   Used by submit_stripe_bio() for mapping logical bio
472 *   into physical device address.
473 *
474 * - Contain device replace info
475 *   Used by handle_ops_on_dev_replace() to copy logical bios
476 *   into the new device.
477 *
478 * - Contain RAID56 full stripe logical bytenrs
479 */
480struct btrfs_io_context {
481	refcount_t refs;
482	struct btrfs_fs_info *fs_info;
483	/* Taken from struct btrfs_chunk_map::type. */
484	u64 map_type;
485	struct bio *orig_bio;
 
486	atomic_t error;
487	u16 max_errors;
488
489	u64 logical;
490	u64 size;
491	/* Raid stripe tree ordered entry. */
492	struct list_head rst_ordered_entry;
493
494	/*
495	 * The total number of stripes, including the extra duplicated
496	 * stripe for replace.
497	 */
498	u16 num_stripes;
499
500	/*
501	 * The mirror_num of this bioc.
502	 *
503	 * This is for reads which use 0 as mirror_num, thus we should return a
504	 * valid mirror_num (>0) for the reader.
505	 */
506	u16 mirror_num;
507
508	/*
509	 * The following two members are for dev-replace case only.
510	 *
511	 * @replace_nr_stripes:	Number of duplicated stripes which need to be
512	 *			written to replace target.
513	 *			Should be <= 2 (2 for DUP, otherwise <= 1).
514	 * @replace_stripe_src:	The array indicates where the duplicated stripes
515	 *			are from.
516	 *
517	 * The @replace_stripe_src[] array is mostly for RAID56 cases.
518	 * As non-RAID56 stripes share the same contents of the mapped range,
519	 * thus no need to bother where the duplicated ones are from.
520	 *
521	 * But for RAID56 case, all stripes contain different contents, thus
522	 * we need a way to know the mapping.
523	 *
524	 * There is an example for the two members, using a RAID5 write:
525	 *
526	 *   num_stripes:	4 (3 + 1 duplicated write)
527	 *   stripes[0]:	dev = devid 1, physical = X
528	 *   stripes[1]:	dev = devid 2, physical = Y
529	 *   stripes[2]:	dev = devid 3, physical = Z
530	 *   stripes[3]:	dev = devid 0, physical = Y
531	 *
532	 * replace_nr_stripes = 1
533	 * replace_stripe_src = 1	<- Means stripes[1] is involved in replace.
534	 *				   The duplicated stripe index would be
535	 *				   (@num_stripes - 1).
536	 *
537	 * Note, that we can still have cases replace_nr_stripes = 2 for DUP.
538	 * In that case, all stripes share the same content, thus we don't
539	 * need to bother @replace_stripe_src value at all.
540	 */
541	u16 replace_nr_stripes;
542	s16 replace_stripe_src;
543	/*
544	 * Logical bytenr of the full stripe start, only for RAID56 cases.
545	 *
546	 * When this value is set to other than (u64)-1, the stripes[] should
547	 * follow this pattern:
548	 *
549	 * (real_stripes = num_stripes - replace_nr_stripes)
550	 * (data_stripes = (is_raid6) ? (real_stripes - 2) : (real_stripes - 1))
551	 *
552	 * stripes[0]:			The first data stripe
553	 * stripes[1]:			The second data stripe
554	 * ...
555	 * stripes[data_stripes - 1]:	The last data stripe
556	 * stripes[data_stripes]:	The P stripe
557	 * stripes[data_stripes + 1]:	The Q stripe (only for RAID6).
558	 */
559	u64 full_stripe_logical;
560	struct btrfs_io_stripe stripes[];
561};
562
563struct btrfs_device_info {
564	struct btrfs_device *dev;
565	u64 dev_offset;
566	u64 max_avail;
567	u64 total_avail;
568};
569
570struct btrfs_raid_attr {
571	u8 sub_stripes;		/* sub_stripes info for map */
572	u8 dev_stripes;		/* stripes per dev */
573	u8 devs_max;		/* max devs to use */
574	u8 devs_min;		/* min devs needed */
575	u8 tolerated_failures;	/* max tolerated fail devs */
576	u8 devs_increment;	/* ndevs has to be a multiple of this */
577	u8 ncopies;		/* how many copies to data has */
578	u8 nparity;		/* number of stripes worth of bytes to store
579				 * parity information */
580	u8 mindev_error;	/* error code if min devs requisite is unmet */
581	const char raid_name[8]; /* name of the raid */
582	u64 bg_flag;		/* block group flag of the raid */
583};
584
585extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
586
587struct btrfs_chunk_map {
588	struct rb_node rb_node;
589	/* For mount time dev extent verification. */
590	int verified_stripes;
591	refcount_t refs;
592	u64 start;
593	u64 chunk_len;
594	u64 stripe_size;
595	u64 type;
596	int io_align;
597	int io_width;
 
 
598	int num_stripes;
599	int sub_stripes;
600	struct btrfs_io_stripe stripes[];
601};
602
603#define btrfs_chunk_map_size(n) (sizeof(struct btrfs_chunk_map) + \
604				 (sizeof(struct btrfs_io_stripe) * (n)))
605
606static inline void btrfs_free_chunk_map(struct btrfs_chunk_map *map)
607{
608	if (map && refcount_dec_and_test(&map->refs)) {
609		ASSERT(RB_EMPTY_NODE(&map->rb_node));
610		kfree(map);
611	}
612}
613
614struct btrfs_balance_control {
615	struct btrfs_balance_args data;
616	struct btrfs_balance_args meta;
617	struct btrfs_balance_args sys;
618
619	u64 flags;
620
621	struct btrfs_balance_progress stat;
622};
623
624/*
625 * Search for a given device by the set parameters
626 */
627struct btrfs_dev_lookup_args {
628	u64 devid;
629	u8 *uuid;
630	u8 *fsid;
631	bool missing;
632};
633
634/* We have to initialize to -1 because BTRFS_DEV_REPLACE_DEVID is 0 */
635#define BTRFS_DEV_LOOKUP_ARGS_INIT { .devid = (u64)-1 }
636
637#define BTRFS_DEV_LOOKUP_ARGS(name) \
638	struct btrfs_dev_lookup_args name = BTRFS_DEV_LOOKUP_ARGS_INIT
639
640enum btrfs_map_op {
641	BTRFS_MAP_READ,
642	BTRFS_MAP_WRITE,
643	BTRFS_MAP_GET_READ_MIRRORS,
644};
645
646static inline enum btrfs_map_op btrfs_op(struct bio *bio)
647{
648	switch (bio_op(bio)) {
649	case REQ_OP_WRITE:
650	case REQ_OP_ZONE_APPEND:
651		return BTRFS_MAP_WRITE;
652	default:
653		WARN_ON_ONCE(1);
654		fallthrough;
655	case REQ_OP_READ:
656		return BTRFS_MAP_READ;
657	}
658}
659
660static inline unsigned long btrfs_chunk_item_size(int num_stripes)
661{
662	ASSERT(num_stripes);
663	return sizeof(struct btrfs_chunk) +
664		sizeof(struct btrfs_stripe) * (num_stripes - 1);
665}
666
667/*
668 * Do the type safe conversion from stripe_nr to offset inside the chunk.
669 *
670 * @stripe_nr is u32, with left shift it can overflow u32 for chunks larger
671 * than 4G.  This does the proper type cast to avoid overflow.
672 */
673static inline u64 btrfs_stripe_nr_to_offset(u32 stripe_nr)
674{
675	return (u64)stripe_nr << BTRFS_STRIPE_LEN_SHIFT;
676}
677
678void btrfs_get_bioc(struct btrfs_io_context *bioc);
679void btrfs_put_bioc(struct btrfs_io_context *bioc);
680int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
681		    u64 logical, u64 *length,
682		    struct btrfs_io_context **bioc_ret,
683		    struct btrfs_io_stripe *smap, int *mirror_num_ret);
684int btrfs_map_repair_block(struct btrfs_fs_info *fs_info,
685			   struct btrfs_io_stripe *smap, u64 logical,
686			   u32 length, int mirror_num);
687struct btrfs_discard_stripe *btrfs_map_discard(struct btrfs_fs_info *fs_info,
688					       u64 logical, u64 *length_ret,
689					       u32 *num_stripes);
690int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
691int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
692struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans,
693					    u64 type);
694void btrfs_mapping_tree_free(struct btrfs_fs_info *fs_info);
695int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
696		       blk_mode_t flags, void *holder);
697struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags,
698					   bool mount_arg_dev);
699int btrfs_forget_devices(dev_t devt);
700void btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
701void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices);
702void btrfs_assign_next_active_device(struct btrfs_device *device,
703				     struct btrfs_device *this_dev);
704struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
705						  u64 devid,
706						  const char *devpath);
707int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
708				 struct btrfs_dev_lookup_args *args,
709				 const char *path);
710struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
711					const u64 *devid, const u8 *uuid,
712					const char *path);
713void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args);
714int btrfs_rm_device(struct btrfs_fs_info *fs_info,
715		    struct btrfs_dev_lookup_args *args,
716		    struct file **bdev_file);
717void __exit btrfs_cleanup_fs_uuids(void);
718int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
719int btrfs_grow_device(struct btrfs_trans_handle *trans,
720		      struct btrfs_device *device, u64 new_size);
721struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices,
722				       const struct btrfs_dev_lookup_args *args);
723int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
724int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
725int btrfs_balance(struct btrfs_fs_info *fs_info,
726		  struct btrfs_balance_control *bctl,
727		  struct btrfs_ioctl_balance_args *bargs);
728void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
729int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
730int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
731int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
732int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset);
733int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
734bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset);
735void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
736int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
737			struct btrfs_ioctl_get_dev_stats *stats);
738int btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
739int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
740int btrfs_run_dev_stats(struct btrfs_trans_handle *trans);
741void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);
742void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);
743void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);
744unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
745				    u64 logical);
746u64 btrfs_calc_stripe_length(const struct btrfs_chunk_map *map);
747int btrfs_nr_parity_stripes(u64 type);
748int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans,
749				     struct btrfs_block_group *bg);
750int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);
751
752#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
753struct btrfs_chunk_map *btrfs_alloc_chunk_map(int num_stripes, gfp_t gfp);
754int btrfs_add_chunk_map(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map);
755#endif
756
757struct btrfs_chunk_map *btrfs_find_chunk_map(struct btrfs_fs_info *fs_info,
758					     u64 logical, u64 length);
759struct btrfs_chunk_map *btrfs_find_chunk_map_nolock(struct btrfs_fs_info *fs_info,
760						    u64 logical, u64 length);
761struct btrfs_chunk_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
762					    u64 logical, u64 length);
763void btrfs_remove_chunk_map(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map);
764void btrfs_release_disk_super(struct btrfs_super_block *super);
765
766static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
767				      int index)
768{
769	atomic_inc(dev->dev_stat_values + index);
770	/*
771	 * This memory barrier orders stores updating statistics before stores
772	 * updating dev_stats_ccnt.
773	 *
774	 * It pairs with smp_rmb() in btrfs_run_dev_stats().
775	 */
776	smp_mb__before_atomic();
777	atomic_inc(&dev->dev_stats_ccnt);
778}
779
780static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
781				      int index)
782{
783	return atomic_read(dev->dev_stat_values + index);
784}
785
786static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
787						int index)
788{
789	int ret;
790
791	ret = atomic_xchg(dev->dev_stat_values + index, 0);
792	/*
793	 * atomic_xchg implies a full memory barriers as per atomic_t.txt:
794	 * - RMW operations that have a return value are fully ordered;
795	 *
796	 * This implicit memory barriers is paired with the smp_rmb in
797	 * btrfs_run_dev_stats
798	 */
799	atomic_inc(&dev->dev_stats_ccnt);
800	return ret;
801}
802
803static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
804				      int index, unsigned long val)
805{
806	atomic_set(dev->dev_stat_values + index, val);
807	/*
808	 * This memory barrier orders stores updating statistics before stores
809	 * updating dev_stats_ccnt.
810	 *
811	 * It pairs with smp_rmb() in btrfs_run_dev_stats().
812	 */
813	smp_mb__before_atomic();
814	atomic_inc(&dev->dev_stats_ccnt);
815}
816
817static inline const char *btrfs_dev_name(const struct btrfs_device *device)
818{
819	if (!device || test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state))
820		return "<missing disk>";
821	else
822		return rcu_str_deref(device->name);
823}
824
825void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
826
827struct list_head * __attribute_const__ btrfs_get_fs_uuids(void);
828bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
829					struct btrfs_device *failing_dev);
830void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info, struct btrfs_device *device);
831
832enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags);
833int btrfs_bg_type_to_factor(u64 flags);
834const char *btrfs_bg_type_to_raid_name(u64 flags);
835int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
836bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical);
837
838bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr);
839const u8 *btrfs_sb_fsid_ptr(const struct btrfs_super_block *sb);
840
841#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
842struct btrfs_io_context *alloc_btrfs_io_context(struct btrfs_fs_info *fs_info,
843						u64 logical, u16 total_stripes);
844#endif
845
846#endif
v3.1
 
  1/*
  2 * Copyright (C) 2007 Oracle.  All rights reserved.
  3 *
  4 * This program is free software; you can redistribute it and/or
  5 * modify it under the terms of the GNU General Public
  6 * License v2 as published by the Free Software Foundation.
  7 *
  8 * This program is distributed in the hope that it will be useful,
  9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 11 * General Public License for more details.
 12 *
 13 * You should have received a copy of the GNU General Public
 14 * License along with this program; if not, write to the
 15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 16 * Boston, MA 021110-1307, USA.
 17 */
 18
 19#ifndef __BTRFS_VOLUMES_
 20#define __BTRFS_VOLUMES_
 21
 22#include <linux/bio.h>
 
 
 23#include <linux/sort.h>
 24#include "async-thread.h"
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 25
 26#define BTRFS_STRIPE_LEN	(64 * 1024)
 27
 28struct buffer_head;
 29struct btrfs_pending_bios {
 30	struct bio *head;
 31	struct bio *tail;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 32};
 33
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 34struct btrfs_device {
 35	struct list_head dev_list;
 36	struct list_head dev_alloc_list;
 
 37	struct btrfs_fs_devices *fs_devices;
 38	struct btrfs_root *dev_root;
 39
 40	/* regular prio bios */
 41	struct btrfs_pending_bios pending_bios;
 42	/* WRITE_SYNC bios */
 43	struct btrfs_pending_bios pending_sync_bios;
 44
 45	int running_pending;
 46	u64 generation;
 47
 48	int writeable;
 49	int in_fs_metadata;
 50	int missing;
 51	int can_discard;
 52
 53	spinlock_t io_lock;
 54
 55	struct block_device *bdev;
 56
 57	/* the mode sent to blkdev_get */
 58	fmode_t mode;
 59
 60	char *name;
 
 
 
 
 
 
 
 
 
 
 61
 62	/* the internal btrfs device id */
 63	u64 devid;
 64
 65	/* size of the device */
 66	u64 total_bytes;
 67
 68	/* size of the disk */
 69	u64 disk_total_bytes;
 70
 71	/* bytes used */
 72	u64 bytes_used;
 73
 74	/* optimal io alignment for this device */
 75	u32 io_align;
 76
 77	/* optimal io width for this device */
 78	u32 io_width;
 
 
 
 
 
 
 
 
 79
 80	/* minimal io size for this device */
 81	u32 sector_size;
 82
 83	/* type and info about this device */
 84	u64 type;
 85
 86	/* physical drive uuid (or lvm uuid) */
 87	u8 uuid[BTRFS_UUID_SIZE];
 88
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 89	/* per-device scrub information */
 90	struct scrub_dev *scrub_device;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 91
 92	struct btrfs_work work;
 93	struct rcu_head rcu;
 94	struct work_struct rcu_work;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 95};
 
 96
 97struct btrfs_fs_devices {
 98	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
 99
100	/* the device with this id has the most recent copy of the super */
101	u64 latest_devid;
102	u64 latest_trans;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
103	u64 num_devices;
 
 
 
 
 
104	u64 open_devices;
 
 
105	u64 rw_devices;
 
 
106	u64 missing_devices;
107	u64 total_rw_bytes;
108	u64 num_can_discard;
109	struct block_device *latest_bdev;
110
111	/* all of the devices in the FS, protected by a mutex
112	 * so we can safely walk it to write out the supers without
113	 * worrying about add/remove by the multi-device code
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
114	 */
115	struct mutex device_list_mutex;
 
 
116	struct list_head devices;
117
118	/* devices not currently being allocated */
119	struct list_head alloc_list;
120	struct list_head list;
121
122	struct btrfs_fs_devices *seed;
123	int seeding;
124
 
125	int opened;
126
127	/* set when we find or add a device that doesn't have the
128	 * nonrot flag set
129	 */
130	int rotating;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
131};
132
133struct btrfs_bio_stripe {
134	struct btrfs_device *dev;
135	u64 physical;
136	u64 length; /* only used for discard mappings */
137};
138
139struct btrfs_multi_bio {
140	atomic_t stripes_pending;
141	bio_end_io_t *end_io;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
142	struct bio *orig_bio;
143	void *private;
144	atomic_t error;
145	int max_errors;
146	int num_stripes;
147	struct btrfs_bio_stripe stripes[];
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
148};
149
150struct btrfs_device_info {
151	struct btrfs_device *dev;
152	u64 dev_offset;
153	u64 max_avail;
154	u64 total_avail;
155};
156
157struct map_lookup {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
158	u64 type;
159	int io_align;
160	int io_width;
161	int stripe_len;
162	int sector_size;
163	int num_stripes;
164	int sub_stripes;
165	struct btrfs_bio_stripe stripes[];
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
166};
167
168#define map_lookup_size(n) (sizeof(struct map_lookup) + \
169			    (sizeof(struct btrfs_bio_stripe) * (n)))
 
 
 
 
 
 
 
170
171int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
172				   u64 end, u64 *length);
 
 
 
 
 
 
 
 
 
173
174#define btrfs_multi_bio_size(n) (sizeof(struct btrfs_multi_bio) + \
175			    (sizeof(struct btrfs_bio_stripe) * (n)))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
176
177int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
178			   struct btrfs_device *device,
179			   u64 chunk_tree, u64 chunk_objectid,
180			   u64 chunk_offset, u64 start, u64 num_bytes);
181int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
 
 
 
 
 
 
 
 
 
182		    u64 logical, u64 *length,
183		    struct btrfs_multi_bio **multi_ret, int mirror_num);
184int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
185		     u64 chunk_start, u64 physical, u64 devid,
186		     u64 **logical, int *naddrs, int *stripe_len);
187int btrfs_read_sys_array(struct btrfs_root *root);
188int btrfs_read_chunk_tree(struct btrfs_root *root);
189int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
190		      struct btrfs_root *extent_root, u64 type);
191void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
192void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
193int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
194		  int mirror_num, int async_submit);
 
195int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
196		       fmode_t flags, void *holder);
197int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
198			  struct btrfs_fs_devices **fs_devices_ret);
199int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
200int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices);
201int btrfs_add_device(struct btrfs_trans_handle *trans,
202		     struct btrfs_root *root,
203		     struct btrfs_device *device);
204int btrfs_rm_device(struct btrfs_root *root, char *device_path);
205int btrfs_cleanup_fs_uuids(void);
206int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len);
 
 
 
 
 
 
 
 
 
 
 
 
207int btrfs_grow_device(struct btrfs_trans_handle *trans,
208		      struct btrfs_device *device, u64 new_size);
209struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
210				       u8 *uuid, u8 *fsid);
211int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
212int btrfs_init_new_device(struct btrfs_root *root, char *path);
213int btrfs_balance(struct btrfs_root *dev_root);
214int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
215int find_free_dev_extent(struct btrfs_trans_handle *trans,
216			 struct btrfs_device *device, u64 num_bytes,
217			 u64 *start, u64 *max_avail);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
218#endif