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	(64 * 1024)
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
55	struct btrfs_root *dev_root;
56
57	struct rcu_string *name;
58
59	u64 generation;
60
61	spinlock_t io_lock ____cacheline_aligned;
62	int running_pending;
63	/* regular prio bios */
64	struct btrfs_pending_bios pending_bios;
65	/* WRITE_SYNC bios */
66	struct btrfs_pending_bios pending_sync_bios;
67
68	struct block_device *bdev;
69
70	/* the mode sent to blkdev_get */
71	fmode_t mode;
72
73	int writeable;
74	int in_fs_metadata;
75	int missing;
76	int can_discard;
77	int is_tgtdev_for_dev_replace;
78
79#ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
80	seqcount_t data_seqcount;
81#endif
82
83	/* the internal btrfs device id */
84	u64 devid;
85
86	/* size of the device in memory */
87	u64 total_bytes;
88
89	/* size of the device on disk */
90	u64 disk_total_bytes;
91
92	/* bytes used */
93	u64 bytes_used;
94
95	/* optimal io alignment for this device */
96	u32 io_align;
97
98	/* optimal io width for this device */
99	u32 io_width;
100	/* type and info about this device */
101	u64 type;
102
103	/* minimal io size for this device */
104	u32 sector_size;
105
106	/* physical drive uuid (or lvm uuid) */
107	u8 uuid[BTRFS_UUID_SIZE];
108
109	/*
110	 * size of the device on the current transaction
111	 *
112	 * This variant is update when committing the transaction,
113	 * and protected by device_list_mutex
114	 */
115	u64 commit_total_bytes;
116
117	/* bytes used on the current transaction */
118	u64 commit_bytes_used;
119	/*
120	 * used to manage the device which is resized
121	 *
122	 * It is protected by chunk_lock.
123	 */
124	struct list_head resized_list;
125
126	/* for sending down flush barriers */
127	int nobarriers;
128	struct bio *flush_bio;
129	struct completion flush_wait;
130
131	/* per-device scrub information */
132	struct scrub_ctx *scrub_device;
133
134	struct btrfs_work work;
135	struct rcu_head rcu;
136	struct work_struct rcu_work;
137
138	/* readahead state */
139	spinlock_t reada_lock;
140	atomic_t reada_in_flight;
141	u64 reada_next;
142	struct reada_zone *reada_curr_zone;
143	struct radix_tree_root reada_zones;
144	struct radix_tree_root reada_extents;
145
146	/* disk I/O failure stats. For detailed description refer to
147	 * enum btrfs_dev_stat_values in ioctl.h */
148	int dev_stats_valid;
149
150	/* Counter to record the change of device stats */
151	atomic_t dev_stats_ccnt;
152	atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
153};
154
155/*
156 * If we read those variants at the context of their own lock, we needn't
157 * use the following helpers, reading them directly is safe.
158 */
159#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
160#define BTRFS_DEVICE_GETSET_FUNCS(name)					\
161static inline u64							\
162btrfs_device_get_##name(const struct btrfs_device *dev)			\
163{									\
164	u64 size;							\
165	unsigned int seq;						\
166									\
167	do {								\
168		seq = read_seqcount_begin(&dev->data_seqcount);		\
169		size = dev->name;					\
170	} while (read_seqcount_retry(&dev->data_seqcount, seq));	\
171	return size;							\
172}									\
173									\
174static inline void							\
175btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
176{									\
177	preempt_disable();						\
178	write_seqcount_begin(&dev->data_seqcount);			\
179	dev->name = size;						\
180	write_seqcount_end(&dev->data_seqcount);			\
181	preempt_enable();						\
182}
183#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
184#define BTRFS_DEVICE_GETSET_FUNCS(name)					\
185static inline u64							\
186btrfs_device_get_##name(const struct btrfs_device *dev)			\
187{									\
188	u64 size;							\
189									\
190	preempt_disable();						\
191	size = dev->name;						\
192	preempt_enable();						\
193	return size;							\
194}									\
195									\
196static inline void							\
197btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
198{									\
199	preempt_disable();						\
200	dev->name = size;						\
201	preempt_enable();						\
202}
203#else
204#define BTRFS_DEVICE_GETSET_FUNCS(name)					\
205static inline u64							\
206btrfs_device_get_##name(const struct btrfs_device *dev)			\
207{									\
208	return dev->name;						\
209}									\
210									\
211static inline void							\
212btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
213{									\
214	dev->name = size;						\
215}
216#endif
217
218BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
219BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
220BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
221
222struct btrfs_fs_devices {
223	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
224
225	u64 num_devices;
226	u64 open_devices;
227	u64 rw_devices;
228	u64 missing_devices;
229	u64 total_rw_bytes;
230	u64 total_devices;
231	struct block_device *latest_bdev;
232
233	/* all of the devices in the FS, protected by a mutex
234	 * so we can safely walk it to write out the supers without
235	 * worrying about add/remove by the multi-device code.
236	 * Scrubbing super can kick off supers writing by holding
237	 * this mutex lock.
238	 */
239	struct mutex device_list_mutex;
240	struct list_head devices;
241
242	struct list_head resized_devices;
243	/* devices not currently being allocated */
244	struct list_head alloc_list;
245	struct list_head list;
246
247	struct btrfs_fs_devices *seed;
248	int seeding;
249
250	int opened;
251
252	/* set when we find or add a device that doesn't have the
253	 * nonrot flag set
254	 */
255	int rotating;
256};
257
258#define BTRFS_BIO_INLINE_CSUM_SIZE	64
259
260/*
261 * we need the mirror number and stripe index to be passed around
262 * the call chain while we are processing end_io (especially errors).
263 * Really, what we need is a btrfs_bio structure that has this info
264 * and is properly sized with its stripe array, but we're not there
265 * quite yet.  We have our own btrfs bioset, and all of the bios
266 * we allocate are actually btrfs_io_bios.  We'll cram as much of
267 * struct btrfs_bio as we can into this over time.
268 */
269typedef void (btrfs_io_bio_end_io_t) (struct btrfs_io_bio *bio, int err);
270struct btrfs_io_bio {
271	unsigned int mirror_num;
272	unsigned int stripe_index;
273	u64 logical;
274	u8 *csum;
275	u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
276	u8 *csum_allocated;
277	btrfs_io_bio_end_io_t *end_io;
278	struct bio bio;
279};
280
281static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
282{
283	return container_of(bio, struct btrfs_io_bio, bio);
284}
285
286struct btrfs_bio_stripe {
287	struct btrfs_device *dev;
288	u64 physical;
289	u64 length; /* only used for discard mappings */
290};
291
292struct btrfs_bio;
293typedef void (btrfs_bio_end_io_t) (struct btrfs_bio *bio, int err);
294
295#define BTRFS_BIO_ORIG_BIO_SUBMITTED	(1 << 0)
296
297struct btrfs_bio {
298	atomic_t refs;
299	atomic_t stripes_pending;
300	struct btrfs_fs_info *fs_info;
301	u64 map_type; /* get from map_lookup->type */
302	bio_end_io_t *end_io;
303	struct bio *orig_bio;
304	unsigned long flags;
305	void *private;
306	atomic_t error;
307	int max_errors;
308	int num_stripes;
309	int mirror_num;
310	int num_tgtdevs;
311	int *tgtdev_map;
312	/*
313	 * logical block numbers for the start of each stripe
314	 * The last one or two are p/q.  These are sorted,
315	 * so raid_map[0] is the start of our full stripe
316	 */
317	u64 *raid_map;
318	struct btrfs_bio_stripe stripes[];
319};
320
321struct btrfs_device_info {
322	struct btrfs_device *dev;
323	u64 dev_offset;
324	u64 max_avail;
325	u64 total_avail;
326};
327
328struct btrfs_raid_attr {
329	int sub_stripes;	/* sub_stripes info for map */
330	int dev_stripes;	/* stripes per dev */
331	int devs_max;		/* max devs to use */
332	int devs_min;		/* min devs needed */
333	int devs_increment;	/* ndevs has to be a multiple of this */
334	int ncopies;		/* how many copies to data has */
335};
336
337struct map_lookup {
338	u64 type;
339	int io_align;
340	int io_width;
341	int stripe_len;
342	int sector_size;
343	int num_stripes;
344	int sub_stripes;
345	struct btrfs_bio_stripe stripes[];
346};
347
348#define map_lookup_size(n) (sizeof(struct map_lookup) + \
349			    (sizeof(struct btrfs_bio_stripe) * (n)))
350
351/*
352 * Restriper's general type filter
353 */
354#define BTRFS_BALANCE_DATA		(1ULL << 0)
355#define BTRFS_BALANCE_SYSTEM		(1ULL << 1)
356#define BTRFS_BALANCE_METADATA		(1ULL << 2)
357
358#define BTRFS_BALANCE_TYPE_MASK		(BTRFS_BALANCE_DATA |	    \
359					 BTRFS_BALANCE_SYSTEM |	    \
360					 BTRFS_BALANCE_METADATA)
361
362#define BTRFS_BALANCE_FORCE		(1ULL << 3)
363#define BTRFS_BALANCE_RESUME		(1ULL << 4)
364
365/*
366 * Balance filters
367 */
368#define BTRFS_BALANCE_ARGS_PROFILES	(1ULL << 0)
369#define BTRFS_BALANCE_ARGS_USAGE	(1ULL << 1)
370#define BTRFS_BALANCE_ARGS_DEVID	(1ULL << 2)
371#define BTRFS_BALANCE_ARGS_DRANGE	(1ULL << 3)
372#define BTRFS_BALANCE_ARGS_VRANGE	(1ULL << 4)
373#define BTRFS_BALANCE_ARGS_LIMIT	(1ULL << 5)
374
375#define BTRFS_BALANCE_ARGS_MASK			\
376	(BTRFS_BALANCE_ARGS_PROFILES |		\
377	 BTRFS_BALANCE_ARGS_USAGE |		\
378	 BTRFS_BALANCE_ARGS_DEVID | 		\
379	 BTRFS_BALANCE_ARGS_DRANGE |		\
380	 BTRFS_BALANCE_ARGS_VRANGE |		\
381	 BTRFS_BALANCE_ARGS_LIMIT)
382
383/*
384 * Profile changing flags.  When SOFT is set we won't relocate chunk if
385 * it already has the target profile (even though it may be
386 * half-filled).
387 */
388#define BTRFS_BALANCE_ARGS_CONVERT	(1ULL << 8)
389#define BTRFS_BALANCE_ARGS_SOFT		(1ULL << 9)
390
391struct btrfs_balance_args;
392struct btrfs_balance_progress;
393struct btrfs_balance_control {
394	struct btrfs_fs_info *fs_info;
395
396	struct btrfs_balance_args data;
397	struct btrfs_balance_args meta;
398	struct btrfs_balance_args sys;
399
400	u64 flags;
401
402	struct btrfs_balance_progress stat;
403};
404
405int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
406				   u64 end, u64 *length);
407void btrfs_get_bbio(struct btrfs_bio *bbio);
408void btrfs_put_bbio(struct btrfs_bio *bbio);
409int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
410		    u64 logical, u64 *length,
411		    struct btrfs_bio **bbio_ret, int mirror_num);
412int btrfs_map_sblock(struct btrfs_fs_info *fs_info, int rw,
413		     u64 logical, u64 *length,
414		     struct btrfs_bio **bbio_ret, int mirror_num,
415		     int need_raid_map);
416int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
417		     u64 chunk_start, u64 physical, u64 devid,
418		     u64 **logical, int *naddrs, int *stripe_len);
419int btrfs_read_sys_array(struct btrfs_root *root);
420int btrfs_read_chunk_tree(struct btrfs_root *root);
421int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
422		      struct btrfs_root *extent_root, u64 type);
423void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
424void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
425int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
426		  int mirror_num, int async_submit);
427int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
428		       fmode_t flags, void *holder);
429int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
430			  struct btrfs_fs_devices **fs_devices_ret);
431int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
432void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices, int step);
433int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
434					 char *device_path,
435					 struct btrfs_device **device);
436struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
437					const u64 *devid,
438					const u8 *uuid);
439int btrfs_rm_device(struct btrfs_root *root, char *device_path);
440void btrfs_cleanup_fs_uuids(void);
441int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
442int btrfs_grow_device(struct btrfs_trans_handle *trans,
443		      struct btrfs_device *device, u64 new_size);
444struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
445				       u8 *uuid, u8 *fsid);
446int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
447int btrfs_init_new_device(struct btrfs_root *root, char *path);
448int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
449				  struct btrfs_device *srcdev,
450				  struct btrfs_device **device_out);
451int btrfs_balance(struct btrfs_balance_control *bctl,
452		  struct btrfs_ioctl_balance_args *bargs);
453int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
454int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
455int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
456int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
457int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
458int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info);
459int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
460int find_free_dev_extent(struct btrfs_trans_handle *trans,
461			 struct btrfs_device *device, u64 num_bytes,
462			 u64 *start, u64 *max_avail);
463void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
464int btrfs_get_dev_stats(struct btrfs_root *root,
465			struct btrfs_ioctl_get_dev_stats *stats);
466void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
467int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
468int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
469			struct btrfs_fs_info *fs_info);
470void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
471					struct btrfs_device *srcdev);
472void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
473				      struct btrfs_device *srcdev);
474void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
475				      struct btrfs_device *tgtdev);
476void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
477					      struct btrfs_device *tgtdev);
478int btrfs_scratch_superblock(struct btrfs_device *device);
479int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
480			   u64 logical, u64 len, int mirror_num);
481unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
482				    struct btrfs_mapping_tree *map_tree,
483				    u64 logical);
484int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
485				struct btrfs_root *extent_root,
486				u64 chunk_offset, u64 chunk_size);
487int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
488		       struct btrfs_root *root, u64 chunk_offset);
489
490static inline int btrfs_dev_stats_dirty(struct btrfs_device *dev)
491{
492	return atomic_read(&dev->dev_stats_ccnt);
493}
494
495static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
496				      int index)
497{
498	atomic_inc(dev->dev_stat_values + index);
499	smp_mb__before_atomic();
500	atomic_inc(&dev->dev_stats_ccnt);
501}
502
503static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
504				      int index)
505{
506	return atomic_read(dev->dev_stat_values + index);
507}
508
509static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
510						int index)
511{
512	int ret;
513
514	ret = atomic_xchg(dev->dev_stat_values + index, 0);
515	smp_mb__before_atomic();
516	atomic_inc(&dev->dev_stats_ccnt);
517	return ret;
518}
519
520static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
521				      int index, unsigned long val)
522{
523	atomic_set(dev->dev_stat_values + index, val);
524	smp_mb__before_atomic();
525	atomic_inc(&dev->dev_stats_ccnt);
526}
527
528static inline void btrfs_dev_stat_reset(struct btrfs_device *dev,
529					int index)
530{
531	btrfs_dev_stat_set(dev, index, 0);
532}
533
534void btrfs_update_commit_device_size(struct btrfs_fs_info *fs_info);
535void btrfs_update_commit_device_bytes_used(struct btrfs_root *root,
536					struct btrfs_transaction *transaction);
537
538static inline void lock_chunks(struct btrfs_root *root)
539{
540	mutex_lock(&root->fs_info->chunk_mutex);
541}
542
543static inline void unlock_chunks(struct btrfs_root *root)
544{
545	mutex_unlock(&root->fs_info->chunk_mutex);
546}
547
548
549#endif
550