xref: /linux/fs/btrfs/volumes.h (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 
27 extern struct mutex uuid_mutex;
28 
29 #define BTRFS_STRIPE_LEN	(64 * 1024)
30 
31 struct buffer_head;
32 struct 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 
50 struct 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)					\
161 static inline u64							\
162 btrfs_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 									\
174 static inline void							\
175 btrfs_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)					\
185 static inline u64							\
186 btrfs_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 									\
196 static inline void							\
197 btrfs_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)					\
205 static inline u64							\
206 btrfs_device_get_##name(const struct btrfs_device *dev)			\
207 {									\
208 	return dev->name;						\
209 }									\
210 									\
211 static inline void							\
212 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\
213 {									\
214 	dev->name = size;						\
215 }
216 #endif
217 
218 BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
219 BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
220 BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
221 
222 struct 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 	struct btrfs_fs_info *fs_info;
258 	/* sysfs kobjects */
259 	struct kobject super_kobj;
260 	struct kobject *device_dir_kobj;
261 	struct completion kobj_unregister;
262 };
263 
264 #define BTRFS_BIO_INLINE_CSUM_SIZE	64
265 
266 /*
267  * we need the mirror number and stripe index to be passed around
268  * the call chain while we are processing end_io (especially errors).
269  * Really, what we need is a btrfs_bio structure that has this info
270  * and is properly sized with its stripe array, but we're not there
271  * quite yet.  We have our own btrfs bioset, and all of the bios
272  * we allocate are actually btrfs_io_bios.  We'll cram as much of
273  * struct btrfs_bio as we can into this over time.
274  */
275 typedef void (btrfs_io_bio_end_io_t) (struct btrfs_io_bio *bio, int err);
276 struct btrfs_io_bio {
277 	unsigned int mirror_num;
278 	unsigned int stripe_index;
279 	u64 logical;
280 	u8 *csum;
281 	u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
282 	u8 *csum_allocated;
283 	btrfs_io_bio_end_io_t *end_io;
284 	struct bio bio;
285 };
286 
287 static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
288 {
289 	return container_of(bio, struct btrfs_io_bio, bio);
290 }
291 
292 struct btrfs_bio_stripe {
293 	struct btrfs_device *dev;
294 	u64 physical;
295 	u64 length; /* only used for discard mappings */
296 };
297 
298 struct btrfs_bio;
299 typedef void (btrfs_bio_end_io_t) (struct btrfs_bio *bio, int err);
300 
301 struct btrfs_bio {
302 	atomic_t refs;
303 	atomic_t stripes_pending;
304 	struct btrfs_fs_info *fs_info;
305 	u64 map_type; /* get from map_lookup->type */
306 	bio_end_io_t *end_io;
307 	struct bio *orig_bio;
308 	unsigned long flags;
309 	void *private;
310 	atomic_t error;
311 	int max_errors;
312 	int num_stripes;
313 	int mirror_num;
314 	int num_tgtdevs;
315 	int *tgtdev_map;
316 	/*
317 	 * logical block numbers for the start of each stripe
318 	 * The last one or two are p/q.  These are sorted,
319 	 * so raid_map[0] is the start of our full stripe
320 	 */
321 	u64 *raid_map;
322 	struct btrfs_bio_stripe stripes[];
323 };
324 
325 struct btrfs_device_info {
326 	struct btrfs_device *dev;
327 	u64 dev_offset;
328 	u64 max_avail;
329 	u64 total_avail;
330 };
331 
332 struct btrfs_raid_attr {
333 	int sub_stripes;	/* sub_stripes info for map */
334 	int dev_stripes;	/* stripes per dev */
335 	int devs_max;		/* max devs to use */
336 	int devs_min;		/* min devs needed */
337 	int devs_increment;	/* ndevs has to be a multiple of this */
338 	int ncopies;		/* how many copies to data has */
339 };
340 
341 struct map_lookup {
342 	u64 type;
343 	int io_align;
344 	int io_width;
345 	int stripe_len;
346 	int sector_size;
347 	int num_stripes;
348 	int sub_stripes;
349 	struct btrfs_bio_stripe stripes[];
350 };
351 
352 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
353 			    (sizeof(struct btrfs_bio_stripe) * (n)))
354 
355 /*
356  * Restriper's general type filter
357  */
358 #define BTRFS_BALANCE_DATA		(1ULL << 0)
359 #define BTRFS_BALANCE_SYSTEM		(1ULL << 1)
360 #define BTRFS_BALANCE_METADATA		(1ULL << 2)
361 
362 #define BTRFS_BALANCE_TYPE_MASK		(BTRFS_BALANCE_DATA |	    \
363 					 BTRFS_BALANCE_SYSTEM |	    \
364 					 BTRFS_BALANCE_METADATA)
365 
366 #define BTRFS_BALANCE_FORCE		(1ULL << 3)
367 #define BTRFS_BALANCE_RESUME		(1ULL << 4)
368 
369 /*
370  * Balance filters
371  */
372 #define BTRFS_BALANCE_ARGS_PROFILES	(1ULL << 0)
373 #define BTRFS_BALANCE_ARGS_USAGE	(1ULL << 1)
374 #define BTRFS_BALANCE_ARGS_DEVID	(1ULL << 2)
375 #define BTRFS_BALANCE_ARGS_DRANGE	(1ULL << 3)
376 #define BTRFS_BALANCE_ARGS_VRANGE	(1ULL << 4)
377 #define BTRFS_BALANCE_ARGS_LIMIT	(1ULL << 5)
378 
379 #define BTRFS_BALANCE_ARGS_MASK			\
380 	(BTRFS_BALANCE_ARGS_PROFILES |		\
381 	 BTRFS_BALANCE_ARGS_USAGE |		\
382 	 BTRFS_BALANCE_ARGS_DEVID | 		\
383 	 BTRFS_BALANCE_ARGS_DRANGE |		\
384 	 BTRFS_BALANCE_ARGS_VRANGE |		\
385 	 BTRFS_BALANCE_ARGS_LIMIT)
386 
387 /*
388  * Profile changing flags.  When SOFT is set we won't relocate chunk if
389  * it already has the target profile (even though it may be
390  * half-filled).
391  */
392 #define BTRFS_BALANCE_ARGS_CONVERT	(1ULL << 8)
393 #define BTRFS_BALANCE_ARGS_SOFT		(1ULL << 9)
394 
395 struct btrfs_balance_args;
396 struct btrfs_balance_progress;
397 struct btrfs_balance_control {
398 	struct btrfs_fs_info *fs_info;
399 
400 	struct btrfs_balance_args data;
401 	struct btrfs_balance_args meta;
402 	struct btrfs_balance_args sys;
403 
404 	u64 flags;
405 
406 	struct btrfs_balance_progress stat;
407 };
408 
409 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
410 				   u64 end, u64 *length);
411 void btrfs_get_bbio(struct btrfs_bio *bbio);
412 void btrfs_put_bbio(struct btrfs_bio *bbio);
413 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
414 		    u64 logical, u64 *length,
415 		    struct btrfs_bio **bbio_ret, int mirror_num);
416 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, int rw,
417 		     u64 logical, u64 *length,
418 		     struct btrfs_bio **bbio_ret, int mirror_num,
419 		     int need_raid_map);
420 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
421 		     u64 chunk_start, u64 physical, u64 devid,
422 		     u64 **logical, int *naddrs, int *stripe_len);
423 int btrfs_read_sys_array(struct btrfs_root *root);
424 int btrfs_read_chunk_tree(struct btrfs_root *root);
425 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
426 		      struct btrfs_root *extent_root, u64 type);
427 void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
428 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
429 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
430 		  int mirror_num, int async_submit);
431 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
432 		       fmode_t flags, void *holder);
433 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
434 			  struct btrfs_fs_devices **fs_devices_ret);
435 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
436 void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices, int step);
437 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
438 					 char *device_path,
439 					 struct btrfs_device **device);
440 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
441 					const u64 *devid,
442 					const u8 *uuid);
443 int btrfs_rm_device(struct btrfs_root *root, char *device_path);
444 void btrfs_cleanup_fs_uuids(void);
445 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
446 int btrfs_grow_device(struct btrfs_trans_handle *trans,
447 		      struct btrfs_device *device, u64 new_size);
448 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
449 				       u8 *uuid, u8 *fsid);
450 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
451 int btrfs_init_new_device(struct btrfs_root *root, char *path);
452 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
453 				  struct btrfs_device *srcdev,
454 				  struct btrfs_device **device_out);
455 int btrfs_balance(struct btrfs_balance_control *bctl,
456 		  struct btrfs_ioctl_balance_args *bargs);
457 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
458 int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
459 int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
460 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
461 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
462 int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info);
463 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
464 int find_free_dev_extent_start(struct btrfs_transaction *transaction,
465 			 struct btrfs_device *device, u64 num_bytes,
466 			 u64 search_start, u64 *start, u64 *max_avail);
467 int find_free_dev_extent(struct btrfs_trans_handle *trans,
468 			 struct btrfs_device *device, u64 num_bytes,
469 			 u64 *start, u64 *max_avail);
470 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
471 int btrfs_get_dev_stats(struct btrfs_root *root,
472 			struct btrfs_ioctl_get_dev_stats *stats);
473 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
474 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
475 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
476 			struct btrfs_fs_info *fs_info);
477 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
478 					struct btrfs_device *srcdev);
479 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
480 				      struct btrfs_device *srcdev);
481 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
482 				      struct btrfs_device *tgtdev);
483 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
484 					      struct btrfs_device *tgtdev);
485 int btrfs_scratch_superblock(struct btrfs_device *device);
486 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
487 			   u64 logical, u64 len, int mirror_num);
488 unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
489 				    struct btrfs_mapping_tree *map_tree,
490 				    u64 logical);
491 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
492 				struct btrfs_root *extent_root,
493 				u64 chunk_offset, u64 chunk_size);
494 int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
495 		       struct btrfs_root *root, u64 chunk_offset);
496 
497 static inline int btrfs_dev_stats_dirty(struct btrfs_device *dev)
498 {
499 	return atomic_read(&dev->dev_stats_ccnt);
500 }
501 
502 static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
503 				      int index)
504 {
505 	atomic_inc(dev->dev_stat_values + index);
506 	smp_mb__before_atomic();
507 	atomic_inc(&dev->dev_stats_ccnt);
508 }
509 
510 static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
511 				      int index)
512 {
513 	return atomic_read(dev->dev_stat_values + index);
514 }
515 
516 static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
517 						int index)
518 {
519 	int ret;
520 
521 	ret = atomic_xchg(dev->dev_stat_values + index, 0);
522 	smp_mb__before_atomic();
523 	atomic_inc(&dev->dev_stats_ccnt);
524 	return ret;
525 }
526 
527 static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
528 				      int index, unsigned long val)
529 {
530 	atomic_set(dev->dev_stat_values + index, val);
531 	smp_mb__before_atomic();
532 	atomic_inc(&dev->dev_stats_ccnt);
533 }
534 
535 static inline void btrfs_dev_stat_reset(struct btrfs_device *dev,
536 					int index)
537 {
538 	btrfs_dev_stat_set(dev, index, 0);
539 }
540 
541 void btrfs_update_commit_device_size(struct btrfs_fs_info *fs_info);
542 void btrfs_update_commit_device_bytes_used(struct btrfs_root *root,
543 					struct btrfs_transaction *transaction);
544 
545 static inline void lock_chunks(struct btrfs_root *root)
546 {
547 	mutex_lock(&root->fs_info->chunk_mutex);
548 }
549 
550 static inline void unlock_chunks(struct btrfs_root *root)
551 {
552 	mutex_unlock(&root->fs_info->chunk_mutex);
553 }
554 
555 struct list_head *btrfs_get_fs_uuids(void);
556 void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info);
557 void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info);
558 
559 #endif
560