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v4.10.11
  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 <linux/btrfs.h>
 25#include "async-thread.h"
 26
 27extern struct mutex uuid_mutex;
 28
 29#define BTRFS_STRIPE_LEN	SZ_64K
 30
 31struct buffer_head;
 32struct btrfs_pending_bios {
 33	struct bio *head;
 34	struct bio *tail;
 35};
 36
 37/*
 38 * Use sequence counter to get consistent device stat data on
 39 * 32-bit processors.
 40 */
 41#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 42#include <linux/seqlock.h>
 43#define __BTRFS_NEED_DEVICE_DATA_ORDERED
 44#define btrfs_device_data_ordered_init(device)	\
 45	seqcount_init(&device->data_seqcount)
 46#else
 47#define btrfs_device_data_ordered_init(device) do { } while (0)
 48#endif
 49
 50struct btrfs_device {
 51	struct list_head dev_list;
 52	struct list_head dev_alloc_list;
 53	struct btrfs_fs_devices *fs_devices;
 54	struct btrfs_fs_info *fs_info;
 55
 56	struct rcu_string *name;
 57
 58	u64 generation;
 59
 60	spinlock_t io_lock ____cacheline_aligned;
 61	int running_pending;
 62	/* regular prio bios */
 63	struct btrfs_pending_bios pending_bios;
 64	/* sync bios */
 65	struct btrfs_pending_bios pending_sync_bios;
 66
 67	struct block_device *bdev;
 68
 69	/* the mode sent to blkdev_get */
 70	fmode_t mode;
 71
 72	int writeable;
 73	int in_fs_metadata;
 74	int missing;
 75	int can_discard;
 76	int is_tgtdev_for_dev_replace;
 77
 78#ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
 79	seqcount_t data_seqcount;
 80#endif
 
 
 
 
 
 81
 82	/* the internal btrfs device id */
 83	u64 devid;
 84
 85	/* size of the device in memory */
 86	u64 total_bytes;
 87
 88	/* size of the device on disk */
 89	u64 disk_total_bytes;
 90
 91	/* bytes used */
 92	u64 bytes_used;
 93
 94	/* optimal io alignment for this device */
 95	u32 io_align;
 96
 97	/* optimal io width for this device */
 98	u32 io_width;
 99	/* type and info about this device */
100	u64 type;
101
102	/* minimal io size for this device */
103	u32 sector_size;
104
 
 
 
105	/* physical drive uuid (or lvm uuid) */
106	u8 uuid[BTRFS_UUID_SIZE];
107
108	/*
109	 * size of the device on the current transaction
110	 *
111	 * This variant is update when committing the transaction,
112	 * and protected by device_list_mutex
113	 */
114	u64 commit_total_bytes;
115
116	/* bytes used on the current transaction */
117	u64 commit_bytes_used;
118	/*
119	 * used to manage the device which is resized
120	 *
121	 * It is protected by chunk_lock.
122	 */
123	struct list_head resized_list;
124
125	/* for sending down flush barriers */
126	int nobarriers;
127	struct bio *flush_bio;
128	struct completion flush_wait;
129
130	/* per-device scrub information */
131	struct scrub_ctx *scrub_device;
132
133	struct btrfs_work work;
134	struct rcu_head rcu;
135	struct work_struct rcu_work;
136
137	/* readahead state */
138	spinlock_t reada_lock;
139	atomic_t reada_in_flight;
140	u64 reada_next;
141	struct reada_zone *reada_curr_zone;
142	struct radix_tree_root reada_zones;
143	struct radix_tree_root reada_extents;
144
145	/* disk I/O failure stats. For detailed description refer to
146	 * enum btrfs_dev_stat_values in ioctl.h */
147	int dev_stats_valid;
148
149	/* Counter to record the change of device stats */
150	atomic_t dev_stats_ccnt;
151	atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
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
 
 
 
224	u64 num_devices;
225	u64 open_devices;
226	u64 rw_devices;
227	u64 missing_devices;
228	u64 total_rw_bytes;
229	u64 total_devices;
230	struct block_device *latest_bdev;
231
232	/* all of the devices in the FS, protected by a mutex
233	 * so we can safely walk it to write out the supers without
234	 * worrying about add/remove by the multi-device code.
235	 * Scrubbing super can kick off supers writing by holding
236	 * this mutex lock.
237	 */
238	struct mutex device_list_mutex;
239	struct list_head devices;
240
241	struct list_head resized_devices;
242	/* devices not currently being allocated */
243	struct list_head alloc_list;
244	struct list_head list;
245
246	struct btrfs_fs_devices *seed;
247	int seeding;
248
249	int opened;
250
251	/* set when we find or add a device that doesn't have the
252	 * nonrot flag set
253	 */
254	int rotating;
255
256	struct btrfs_fs_info *fs_info;
257	/* sysfs kobjects */
258	struct kobject fsid_kobj;
259	struct kobject *device_dir_kobj;
260	struct completion kobj_unregister;
261};
262
263#define BTRFS_BIO_INLINE_CSUM_SIZE	64
264
265/*
266 * we need the mirror number and stripe index to be passed around
267 * the call chain while we are processing end_io (especially errors).
268 * Really, what we need is a btrfs_bio structure that has this info
269 * and is properly sized with its stripe array, but we're not there
270 * quite yet.  We have our own btrfs bioset, and all of the bios
271 * we allocate are actually btrfs_io_bios.  We'll cram as much of
272 * struct btrfs_bio as we can into this over time.
273 */
274typedef void (btrfs_io_bio_end_io_t) (struct btrfs_io_bio *bio, int err);
275struct btrfs_io_bio {
276	unsigned int mirror_num;
277	unsigned int stripe_index;
278	u64 logical;
279	u8 *csum;
280	u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
281	u8 *csum_allocated;
282	btrfs_io_bio_end_io_t *end_io;
283	struct bio bio;
284};
285
286static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
287{
288	return container_of(bio, struct btrfs_io_bio, bio);
289}
290
291struct btrfs_bio_stripe {
292	struct btrfs_device *dev;
293	u64 physical;
294	u64 length; /* only used for discard mappings */
295};
296
297struct btrfs_bio;
298typedef void (btrfs_bio_end_io_t) (struct btrfs_bio *bio, int err);
299
300struct btrfs_bio {
301	atomic_t refs;
302	atomic_t stripes_pending;
303	struct btrfs_fs_info *fs_info;
304	u64 map_type; /* get from map_lookup->type */
305	bio_end_io_t *end_io;
306	struct bio *orig_bio;
307	unsigned long flags;
308	void *private;
309	atomic_t error;
310	int max_errors;
311	int num_stripes;
312	int mirror_num;
313	int num_tgtdevs;
314	int *tgtdev_map;
315	/*
316	 * logical block numbers for the start of each stripe
317	 * The last one or two are p/q.  These are sorted,
318	 * so raid_map[0] is the start of our full stripe
319	 */
320	u64 *raid_map;
321	struct btrfs_bio_stripe stripes[];
322};
323
324struct btrfs_device_info {
325	struct btrfs_device *dev;
326	u64 dev_offset;
327	u64 max_avail;
328	u64 total_avail;
329};
330
331struct btrfs_raid_attr {
332	int sub_stripes;	/* sub_stripes info for map */
333	int dev_stripes;	/* stripes per dev */
334	int devs_max;		/* max devs to use */
335	int devs_min;		/* min devs needed */
336	int tolerated_failures; /* max tolerated fail devs */
337	int devs_increment;	/* ndevs has to be a multiple of this */
338	int ncopies;		/* how many copies to data has */
339};
340
341extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
342extern const int btrfs_raid_mindev_error[BTRFS_NR_RAID_TYPES];
343extern const u64 btrfs_raid_group[BTRFS_NR_RAID_TYPES];
344
345struct map_lookup {
346	u64 type;
347	int io_align;
348	int io_width;
349	u64 stripe_len;
350	int sector_size;
351	int num_stripes;
352	int sub_stripes;
353	struct btrfs_bio_stripe stripes[];
354};
355
356#define map_lookup_size(n) (sizeof(struct map_lookup) + \
357			    (sizeof(struct btrfs_bio_stripe) * (n)))
358
359struct btrfs_balance_args;
360struct btrfs_balance_progress;
361struct btrfs_balance_control {
362	struct btrfs_fs_info *fs_info;
363
364	struct btrfs_balance_args data;
365	struct btrfs_balance_args meta;
366	struct btrfs_balance_args sys;
367
368	u64 flags;
369
370	struct btrfs_balance_progress stat;
371};
372
373enum btrfs_map_op {
374	BTRFS_MAP_READ,
375	BTRFS_MAP_WRITE,
376	BTRFS_MAP_DISCARD,
377	BTRFS_MAP_GET_READ_MIRRORS,
378};
379
380static inline enum btrfs_map_op btrfs_op(struct bio *bio)
381{
382	switch (bio_op(bio)) {
383	case REQ_OP_DISCARD:
384		return BTRFS_MAP_DISCARD;
385	case REQ_OP_WRITE:
386		return BTRFS_MAP_WRITE;
387	default:
388		WARN_ON_ONCE(1);
389	case REQ_OP_READ:
390		return BTRFS_MAP_READ;
391	}
392}
393
394int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
395				   u64 end, u64 *length);
396void btrfs_get_bbio(struct btrfs_bio *bbio);
397void btrfs_put_bbio(struct btrfs_bio *bbio);
398int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
 
 
 
 
 
 
399		    u64 logical, u64 *length,
400		    struct btrfs_bio **bbio_ret, int mirror_num);
401int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
402		     u64 logical, u64 *length,
403		     struct btrfs_bio **bbio_ret, int mirror_num,
404		     int need_raid_map);
405int btrfs_rmap_block(struct btrfs_fs_info *fs_info,
406		     u64 chunk_start, u64 physical, u64 devid,
407		     u64 **logical, int *naddrs, int *stripe_len);
408int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
409int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
410int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
411		      struct btrfs_fs_info *fs_info, u64 type);
412void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
413void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
414int btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
415		  int mirror_num, int async_submit);
416int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
417		       fmode_t flags, void *holder);
418int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
419			  struct btrfs_fs_devices **fs_devices_ret);
420int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
421void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices, int step);
422void btrfs_assign_next_active_device(struct btrfs_fs_info *fs_info,
423		struct btrfs_device *device, struct btrfs_device *this_dev);
424int btrfs_find_device_missing_or_by_path(struct btrfs_fs_info *fs_info,
425					 char *device_path,
426					 struct btrfs_device **device);
427int btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info, u64 devid,
428					 char *devpath,
429					 struct btrfs_device **device);
430struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
431					const u64 *devid,
432					const u8 *uuid);
433int btrfs_rm_device(struct btrfs_fs_info *fs_info,
434		    char *device_path, u64 devid);
435void btrfs_cleanup_fs_uuids(void);
436int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
437int btrfs_grow_device(struct btrfs_trans_handle *trans,
438		      struct btrfs_device *device, u64 new_size);
439struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
440				       u8 *uuid, u8 *fsid);
441int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
442int btrfs_init_new_device(struct btrfs_fs_info *fs_info, char *path);
443int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
444				  char *device_path,
445				  struct btrfs_device *srcdev,
446				  struct btrfs_device **device_out);
447int btrfs_balance(struct btrfs_balance_control *bctl,
448		  struct btrfs_ioctl_balance_args *bargs);
449int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
450int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
451int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
452int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
453int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
454int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info);
455int btrfs_chunk_readonly(struct btrfs_fs_info *fs_info, u64 chunk_offset);
456int find_free_dev_extent_start(struct btrfs_transaction *transaction,
457			 struct btrfs_device *device, u64 num_bytes,
458			 u64 search_start, u64 *start, u64 *max_avail);
459int find_free_dev_extent(struct btrfs_trans_handle *trans,
460			 struct btrfs_device *device, u64 num_bytes,
461			 u64 *start, u64 *max_avail);
462void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
463int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
464			struct btrfs_ioctl_get_dev_stats *stats);
465void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
466int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
467int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
468			struct btrfs_fs_info *fs_info);
469void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
470					struct btrfs_device *srcdev);
471void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
472				      struct btrfs_device *srcdev);
473void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
474				      struct btrfs_device *tgtdev);
475void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
476					      struct btrfs_device *tgtdev);
477void btrfs_scratch_superblocks(struct block_device *bdev, char *device_path);
478int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
479			   u64 logical, u64 len, int mirror_num);
480unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
481				    struct btrfs_mapping_tree *map_tree,
482				    u64 logical);
483int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
484				struct btrfs_fs_info *fs_info,
485				u64 chunk_offset, u64 chunk_size);
486int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
487		       struct btrfs_fs_info *fs_info, u64 chunk_offset);
488
489static inline int btrfs_dev_stats_dirty(struct btrfs_device *dev)
490{
491	return atomic_read(&dev->dev_stats_ccnt);
492}
493
494static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
495				      int index)
496{
497	atomic_inc(dev->dev_stat_values + index);
498	smp_mb__before_atomic();
499	atomic_inc(&dev->dev_stats_ccnt);
500}
501
502static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
503				      int index)
504{
505	return atomic_read(dev->dev_stat_values + index);
506}
507
508static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
509						int index)
510{
511	int ret;
512
513	ret = atomic_xchg(dev->dev_stat_values + index, 0);
514	smp_mb__before_atomic();
515	atomic_inc(&dev->dev_stats_ccnt);
516	return ret;
517}
518
519static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
520				      int index, unsigned long val)
521{
522	atomic_set(dev->dev_stat_values + index, val);
523	smp_mb__before_atomic();
524	atomic_inc(&dev->dev_stats_ccnt);
525}
526
527static inline void btrfs_dev_stat_reset(struct btrfs_device *dev,
528					int index)
529{
530	btrfs_dev_stat_set(dev, index, 0);
531}
532
533void btrfs_update_commit_device_size(struct btrfs_fs_info *fs_info);
534void btrfs_update_commit_device_bytes_used(struct btrfs_fs_info *fs_info,
535					struct btrfs_transaction *transaction);
536
537struct list_head *btrfs_get_fs_uuids(void);
538void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info);
539void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info);
540
541#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