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v5.4
  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
 
 
 
 
 
 
 16extern struct mutex uuid_mutex;
 17
 18#define BTRFS_STRIPE_LEN	SZ_64K
 
 
 
 
 
 
 
 19
 20struct buffer_head;
 21struct btrfs_pending_bios {
 22	struct bio *head;
 23	struct bio *tail;
 24};
 25
 26struct btrfs_io_geometry {
 27	/* remaining bytes before crossing a stripe */
 28	u64 len;
 29	/* offset of logical address in chunk */
 30	u64 offset;
 31	/* length of single IO stripe */
 32	u64 stripe_len;
 33	/* number of stripe where address falls */
 34	u64 stripe_nr;
 35	/* offset of address in stripe */
 36	u64 stripe_offset;
 37	/* offset of raid56 stripe into the chunk */
 38	u64 raid56_stripe_offset;
 
 
 
 
 
 
 
 
 
 
 39};
 40
 41/*
 42 * Use sequence counter to get consistent device stat data on
 43 * 32-bit processors.
 44 */
 45#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 46#include <linux/seqlock.h>
 47#define __BTRFS_NEED_DEVICE_DATA_ORDERED
 48#define btrfs_device_data_ordered_init(device)	\
 49	seqcount_init(&device->data_seqcount)
 50#else
 51#define btrfs_device_data_ordered_init(device) do { } while (0)
 52#endif
 53
 54#define BTRFS_DEV_STATE_WRITEABLE	(0)
 55#define BTRFS_DEV_STATE_IN_FS_METADATA	(1)
 56#define BTRFS_DEV_STATE_MISSING		(2)
 57#define BTRFS_DEV_STATE_REPLACE_TGT	(3)
 58#define BTRFS_DEV_STATE_FLUSH_SENT	(4)
 
 
 
 
 
 
 59
 60struct btrfs_device {
 61	struct list_head dev_list; /* device_list_mutex */
 62	struct list_head dev_alloc_list; /* chunk mutex */
 63	struct list_head post_commit_list; /* chunk mutex */
 64	struct btrfs_fs_devices *fs_devices;
 65	struct btrfs_fs_info *fs_info;
 66
 67	struct rcu_string *name;
 68
 69	u64 generation;
 70
 71	spinlock_t io_lock ____cacheline_aligned;
 72	int running_pending;
 73	/* regular prio bios */
 74	struct btrfs_pending_bios pending_bios;
 75	/* sync bios */
 76	struct btrfs_pending_bios pending_sync_bios;
 77
 78	struct block_device *bdev;
 79
 80	/* the mode sent to blkdev_get */
 81	fmode_t mode;
 82
 
 
 
 
 
 83	unsigned long dev_state;
 84	blk_status_t last_flush_error;
 85
 86#ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
 87	seqcount_t data_seqcount;
 88#endif
 89
 90	/* the internal btrfs device id */
 91	u64 devid;
 92
 93	/* size of the device in memory */
 94	u64 total_bytes;
 95
 96	/* size of the device on disk */
 97	u64 disk_total_bytes;
 98
 99	/* bytes used */
100	u64 bytes_used;
101
102	/* optimal io alignment for this device */
103	u32 io_align;
104
105	/* optimal io width for this device */
106	u32 io_width;
107	/* type and info about this device */
108	u64 type;
109
 
 
 
 
 
 
110	/* minimal io size for this device */
111	u32 sector_size;
112
113	/* physical drive uuid (or lvm uuid) */
114	u8 uuid[BTRFS_UUID_SIZE];
115
116	/*
117	 * size of the device on the current transaction
118	 *
119	 * This variant is update when committing the transaction,
120	 * and protected by chunk mutex
121	 */
122	u64 commit_total_bytes;
123
124	/* bytes used on the current transaction */
125	u64 commit_bytes_used;
126
127	/* for sending down flush barriers */
128	struct bio *flush_bio;
129	struct completion flush_wait;
130
131	/* per-device scrub information */
132	struct scrub_ctx *scrub_ctx;
133
134	struct btrfs_work work;
135
136	/* readahead state */
137	atomic_t reada_in_flight;
138	u64 reada_next;
139	struct reada_zone *reada_curr_zone;
140	struct radix_tree_root reada_zones;
141	struct radix_tree_root reada_extents;
142
143	/* disk I/O failure stats. For detailed description refer to
144	 * enum btrfs_dev_stat_values in ioctl.h */
145	int dev_stats_valid;
146
147	/* Counter to record the change of device stats */
148	atomic_t dev_stats_ccnt;
149	atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
150
151	struct extent_io_tree alloc_state;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
152};
153
154/*
155 * If we read those variants at the context of their own lock, we needn't
156 * use the following helpers, reading them directly is safe.
157 */
158#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
159#define BTRFS_DEVICE_GETSET_FUNCS(name)					\
160static inline u64							\
161btrfs_device_get_##name(const struct btrfs_device *dev)			\
162{									\
163	u64 size;							\
164	unsigned int seq;						\
165									\
166	do {								\
167		seq = read_seqcount_begin(&dev->data_seqcount);		\
168		size = dev->name;					\
169	} while (read_seqcount_retry(&dev->data_seqcount, seq));	\
170	return size;							\
171}									\
172									\
173static inline void							\
174btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
175{									\
176	preempt_disable();						\
177	write_seqcount_begin(&dev->data_seqcount);			\
178	dev->name = size;						\
179	write_seqcount_end(&dev->data_seqcount);			\
180	preempt_enable();						\
181}
182#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
183#define BTRFS_DEVICE_GETSET_FUNCS(name)					\
184static inline u64							\
185btrfs_device_get_##name(const struct btrfs_device *dev)			\
186{									\
187	u64 size;							\
188									\
189	preempt_disable();						\
190	size = dev->name;						\
191	preempt_enable();						\
192	return size;							\
193}									\
194									\
195static inline void							\
196btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
197{									\
198	preempt_disable();						\
199	dev->name = size;						\
200	preempt_enable();						\
201}
202#else
203#define BTRFS_DEVICE_GETSET_FUNCS(name)					\
204static inline u64							\
205btrfs_device_get_##name(const struct btrfs_device *dev)			\
206{									\
207	return dev->name;						\
208}									\
209									\
210static inline void							\
211btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
212{									\
213	dev->name = size;						\
214}
215#endif
216
217BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
218BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
219BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
220
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
221struct btrfs_fs_devices {
222	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
223	u8 metadata_uuid[BTRFS_FSID_SIZE];
224	bool fsid_change;
225	struct list_head fs_list;
226
 
 
 
 
227	u64 num_devices;
 
 
 
 
 
228	u64 open_devices;
 
 
229	u64 rw_devices;
 
 
230	u64 missing_devices;
231	u64 total_rw_bytes;
 
 
 
 
 
 
232	u64 total_devices;
233
234	/* Highest generation number of seen devices */
235	u64 latest_generation;
236
237	struct block_device *latest_bdev;
 
 
 
 
238
239	/* all of the devices in the FS, protected by a mutex
240	 * so we can safely walk it to write out the supers without
241	 * worrying about add/remove by the multi-device code.
242	 * Scrubbing super can kick off supers writing by holding
243	 * this mutex lock.
244	 */
245	struct mutex device_list_mutex;
246
247	/* List of all devices, protected by device_list_mutex */
248	struct list_head devices;
249
250	/*
251	 * Devices which can satisfy space allocation. Protected by
252	 * chunk_mutex
253	 */
254	struct list_head alloc_list;
255
256	struct btrfs_fs_devices *seed;
257	int seeding;
258
 
259	int opened;
260
261	/* set when we find or add a device that doesn't have the
262	 * nonrot flag set
263	 */
264	int rotating;
 
 
 
 
265
266	struct btrfs_fs_info *fs_info;
267	/* sysfs kobjects */
268	struct kobject fsid_kobj;
269	struct kobject *device_dir_kobj;
 
270	struct completion kobj_unregister;
271};
272
273#define BTRFS_BIO_INLINE_CSUM_SIZE	64
 
 
 
 
 
 
 
 
 
274
275#define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info)	\
276			- sizeof(struct btrfs_chunk))		\
277			/ sizeof(struct btrfs_stripe) + 1)
278
279#define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE	\
280				- 2 * sizeof(struct btrfs_disk_key)	\
281				- 2 * sizeof(struct btrfs_chunk))	\
282				/ sizeof(struct btrfs_stripe) + 1)
283
284/*
285 * we need the mirror number and stripe index to be passed around
286 * the call chain while we are processing end_io (especially errors).
287 * Really, what we need is a btrfs_bio structure that has this info
288 * and is properly sized with its stripe array, but we're not there
289 * quite yet.  We have our own btrfs bioset, and all of the bios
290 * we allocate are actually btrfs_io_bios.  We'll cram as much of
291 * struct btrfs_bio as we can into this over time.
292 */
293struct btrfs_io_bio {
294	unsigned int mirror_num;
295	unsigned int stripe_index;
296	u64 logical;
297	u8 *csum;
298	u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
299	struct bvec_iter iter;
300	/*
301	 * This member must come last, bio_alloc_bioset will allocate enough
302	 * bytes for entire btrfs_io_bio but relies on bio being last.
303	 */
304	struct bio bio;
305};
306
307static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
308{
309	return container_of(bio, struct btrfs_io_bio, bio);
310}
311
312static inline void btrfs_io_bio_free_csum(struct btrfs_io_bio *io_bio)
313{
314	if (io_bio->csum != io_bio->csum_inline) {
315		kfree(io_bio->csum);
316		io_bio->csum = NULL;
317	}
318}
319
320struct btrfs_bio_stripe {
321	struct btrfs_device *dev;
322	u64 physical;
323	u64 length; /* only used for discard mappings */
324};
325
326struct btrfs_bio {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
327	refcount_t refs;
328	atomic_t stripes_pending;
329	struct btrfs_fs_info *fs_info;
330	u64 map_type; /* get from map_lookup->type */
331	bio_end_io_t *end_io;
332	struct bio *orig_bio;
333	unsigned long flags;
334	void *private;
335	atomic_t error;
336	int max_errors;
337	int num_stripes;
338	int mirror_num;
339	int num_tgtdevs;
340	int *tgtdev_map;
341	/*
342	 * logical block numbers for the start of each stripe
343	 * The last one or two are p/q.  These are sorted,
344	 * so raid_map[0] is the start of our full stripe
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
345	 */
346	u64 *raid_map;
347	struct btrfs_bio_stripe stripes[];
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
348};
349
350struct btrfs_device_info {
351	struct btrfs_device *dev;
352	u64 dev_offset;
353	u64 max_avail;
354	u64 total_avail;
355};
356
357struct btrfs_raid_attr {
358	u8 sub_stripes;		/* sub_stripes info for map */
359	u8 dev_stripes;		/* stripes per dev */
360	u8 devs_max;		/* max devs to use */
361	u8 devs_min;		/* min devs needed */
362	u8 tolerated_failures;	/* max tolerated fail devs */
363	u8 devs_increment;	/* ndevs has to be a multiple of this */
364	u8 ncopies;		/* how many copies to data has */
365	u8 nparity;		/* number of stripes worth of bytes to store
366				 * parity information */
367	u8 mindev_error;	/* error code if min devs requisite is unmet */
368	const char raid_name[8]; /* name of the raid */
369	u64 bg_flag;		/* block group flag of the raid */
370};
371
372extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
373
374struct map_lookup {
 
 
 
 
 
 
 
375	u64 type;
376	int io_align;
377	int io_width;
378	u64 stripe_len;
379	int num_stripes;
380	int sub_stripes;
381	int verified_stripes; /* For mount time dev extent verification */
382	struct btrfs_bio_stripe stripes[];
383};
384
385#define map_lookup_size(n) (sizeof(struct map_lookup) + \
386			    (sizeof(struct btrfs_bio_stripe) * (n)))
 
 
 
 
 
 
 
 
387
388struct btrfs_balance_args;
389struct btrfs_balance_progress;
390struct btrfs_balance_control {
391	struct btrfs_balance_args data;
392	struct btrfs_balance_args meta;
393	struct btrfs_balance_args sys;
394
395	u64 flags;
396
397	struct btrfs_balance_progress stat;
398};
399
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
400enum btrfs_map_op {
401	BTRFS_MAP_READ,
402	BTRFS_MAP_WRITE,
403	BTRFS_MAP_DISCARD,
404	BTRFS_MAP_GET_READ_MIRRORS,
405};
406
407static inline enum btrfs_map_op btrfs_op(struct bio *bio)
408{
409	switch (bio_op(bio)) {
410	case REQ_OP_DISCARD:
411		return BTRFS_MAP_DISCARD;
412	case REQ_OP_WRITE:
 
413		return BTRFS_MAP_WRITE;
414	default:
415		WARN_ON_ONCE(1);
416		/* fall through */
417	case REQ_OP_READ:
418		return BTRFS_MAP_READ;
419	}
420}
421
422void btrfs_get_bbio(struct btrfs_bio *bbio);
423void btrfs_put_bbio(struct btrfs_bio *bbio);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
424int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
425		    u64 logical, u64 *length,
426		    struct btrfs_bio **bbio_ret, int mirror_num);
427int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
428		     u64 logical, u64 *length,
429		     struct btrfs_bio **bbio_ret);
430int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
431		u64 logical, u64 len, struct btrfs_io_geometry *io_geom);
432int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
433		     u64 physical, u64 **logical, int *naddrs, int *stripe_len);
434int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
435int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
436int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, u64 type);
437void btrfs_mapping_tree_free(struct extent_map_tree *tree);
438blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
439			   int mirror_num, int async_submit);
440int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
441		       fmode_t flags, void *holder);
442struct btrfs_device *btrfs_scan_one_device(const char *path,
443					   fmode_t flags, void *holder);
444int btrfs_forget_devices(const char *path);
445int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
446void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices, int step);
447void btrfs_assign_next_active_device(struct btrfs_device *device,
448				     struct btrfs_device *this_dev);
449struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
450						  u64 devid,
451						  const char *devpath);
 
 
 
452struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
453					const u64 *devid,
454					const u8 *uuid);
455void btrfs_free_device(struct btrfs_device *device);
456int btrfs_rm_device(struct btrfs_fs_info *fs_info,
457		    const char *device_path, u64 devid);
 
458void __exit btrfs_cleanup_fs_uuids(void);
459int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
460int btrfs_grow_device(struct btrfs_trans_handle *trans,
461		      struct btrfs_device *device, u64 new_size);
462struct btrfs_device *btrfs_find_device(struct btrfs_fs_devices *fs_devices,
463				       u64 devid, u8 *uuid, u8 *fsid, bool seed);
464int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
465int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
466int btrfs_balance(struct btrfs_fs_info *fs_info,
467		  struct btrfs_balance_control *bctl,
468		  struct btrfs_ioctl_balance_args *bargs);
469void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
470int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
471int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
472int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
 
473int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
474int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
475int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info);
476int btrfs_chunk_readonly(struct btrfs_fs_info *fs_info, u64 chunk_offset);
477int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
478			 u64 *start, u64 *max_avail);
479void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
480int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
481			struct btrfs_ioctl_get_dev_stats *stats);
482void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
483int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
484int btrfs_run_dev_stats(struct btrfs_trans_handle *trans);
485void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);
486void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);
487void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);
488void btrfs_scratch_superblocks(struct block_device *bdev, const char *device_path);
489int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
490			   u64 logical, u64 len);
491unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
492				    u64 logical);
493int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
494			     u64 chunk_offset, u64 chunk_size);
 
 
495int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);
496struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
497				       u64 logical, u64 length);
 
 
 
 
 
 
 
 
 
 
 
 
498
499static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
500				      int index)
501{
502	atomic_inc(dev->dev_stat_values + index);
503	/*
504	 * This memory barrier orders stores updating statistics before stores
505	 * updating dev_stats_ccnt.
506	 *
507	 * It pairs with smp_rmb() in btrfs_run_dev_stats().
508	 */
509	smp_mb__before_atomic();
510	atomic_inc(&dev->dev_stats_ccnt);
511}
512
513static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
514				      int index)
515{
516	return atomic_read(dev->dev_stat_values + index);
517}
518
519static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
520						int index)
521{
522	int ret;
523
524	ret = atomic_xchg(dev->dev_stat_values + index, 0);
525	/*
526	 * atomic_xchg implies a full memory barriers as per atomic_t.txt:
527	 * - RMW operations that have a return value are fully ordered;
528	 *
529	 * This implicit memory barriers is paired with the smp_rmb in
530	 * btrfs_run_dev_stats
531	 */
532	atomic_inc(&dev->dev_stats_ccnt);
533	return ret;
534}
535
536static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
537				      int index, unsigned long val)
538{
539	atomic_set(dev->dev_stat_values + index, val);
540	/*
541	 * This memory barrier orders stores updating statistics before stores
542	 * updating dev_stats_ccnt.
543	 *
544	 * It pairs with smp_rmb() in btrfs_run_dev_stats().
545	 */
546	smp_mb__before_atomic();
547	atomic_inc(&dev->dev_stats_ccnt);
548}
549
550/*
551 * Convert block group flags (BTRFS_BLOCK_GROUP_*) to btrfs_raid_types, which
552 * can be used as index to access btrfs_raid_array[].
553 */
554static inline enum btrfs_raid_types btrfs_bg_flags_to_raid_index(u64 flags)
555{
556	if (flags & BTRFS_BLOCK_GROUP_RAID10)
557		return BTRFS_RAID_RAID10;
558	else if (flags & BTRFS_BLOCK_GROUP_RAID1)
559		return BTRFS_RAID_RAID1;
560	else if (flags & BTRFS_BLOCK_GROUP_DUP)
561		return BTRFS_RAID_DUP;
562	else if (flags & BTRFS_BLOCK_GROUP_RAID0)
563		return BTRFS_RAID_RAID0;
564	else if (flags & BTRFS_BLOCK_GROUP_RAID5)
565		return BTRFS_RAID_RAID5;
566	else if (flags & BTRFS_BLOCK_GROUP_RAID6)
567		return BTRFS_RAID_RAID6;
568
569	return BTRFS_RAID_SINGLE; /* BTRFS_BLOCK_GROUP_SINGLE */
570}
571
572void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
573
574struct list_head *btrfs_get_fs_uuids(void);
575void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info);
576void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info);
577bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
578					struct btrfs_device *failing_dev);
 
579
 
580int btrfs_bg_type_to_factor(u64 flags);
581const char *btrfs_bg_type_to_raid_name(u64 flags);
582int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
 
 
 
 
 
 
 
 
 
583
584#endif
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