xref: /openbmc/linux/fs/btrfs/volumes.h (revision 4949009e)
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 
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  */
269 typedef void (btrfs_io_bio_end_io_t) (struct btrfs_io_bio *bio, int err);
270 struct 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 
281 static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
282 {
283 	return container_of(bio, struct btrfs_io_bio, bio);
284 }
285 
286 struct btrfs_bio_stripe {
287 	struct btrfs_device *dev;
288 	u64 physical;
289 	u64 length; /* only used for discard mappings */
290 };
291 
292 struct btrfs_bio;
293 typedef void (btrfs_bio_end_io_t) (struct btrfs_bio *bio, int err);
294 
295 #define BTRFS_BIO_ORIG_BIO_SUBMITTED	(1 << 0)
296 
297 struct btrfs_bio {
298 	atomic_t stripes_pending;
299 	struct btrfs_fs_info *fs_info;
300 	bio_end_io_t *end_io;
301 	struct bio *orig_bio;
302 	unsigned long flags;
303 	void *private;
304 	atomic_t error;
305 	int max_errors;
306 	int num_stripes;
307 	int mirror_num;
308 	int num_tgtdevs;
309 	int *tgtdev_map;
310 	struct btrfs_bio_stripe stripes[];
311 };
312 
313 struct btrfs_device_info {
314 	struct btrfs_device *dev;
315 	u64 dev_offset;
316 	u64 max_avail;
317 	u64 total_avail;
318 };
319 
320 struct btrfs_raid_attr {
321 	int sub_stripes;	/* sub_stripes info for map */
322 	int dev_stripes;	/* stripes per dev */
323 	int devs_max;		/* max devs to use */
324 	int devs_min;		/* min devs needed */
325 	int devs_increment;	/* ndevs has to be a multiple of this */
326 	int ncopies;		/* how many copies to data has */
327 };
328 
329 struct map_lookup {
330 	u64 type;
331 	int io_align;
332 	int io_width;
333 	int stripe_len;
334 	int sector_size;
335 	int num_stripes;
336 	int sub_stripes;
337 	struct btrfs_bio_stripe stripes[];
338 };
339 
340 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
341 			    (sizeof(struct btrfs_bio_stripe) * (n)))
342 
343 /*
344  * Restriper's general type filter
345  */
346 #define BTRFS_BALANCE_DATA		(1ULL << 0)
347 #define BTRFS_BALANCE_SYSTEM		(1ULL << 1)
348 #define BTRFS_BALANCE_METADATA		(1ULL << 2)
349 
350 #define BTRFS_BALANCE_TYPE_MASK		(BTRFS_BALANCE_DATA |	    \
351 					 BTRFS_BALANCE_SYSTEM |	    \
352 					 BTRFS_BALANCE_METADATA)
353 
354 #define BTRFS_BALANCE_FORCE		(1ULL << 3)
355 #define BTRFS_BALANCE_RESUME		(1ULL << 4)
356 
357 /*
358  * Balance filters
359  */
360 #define BTRFS_BALANCE_ARGS_PROFILES	(1ULL << 0)
361 #define BTRFS_BALANCE_ARGS_USAGE	(1ULL << 1)
362 #define BTRFS_BALANCE_ARGS_DEVID	(1ULL << 2)
363 #define BTRFS_BALANCE_ARGS_DRANGE	(1ULL << 3)
364 #define BTRFS_BALANCE_ARGS_VRANGE	(1ULL << 4)
365 #define BTRFS_BALANCE_ARGS_LIMIT	(1ULL << 5)
366 
367 /*
368  * Profile changing flags.  When SOFT is set we won't relocate chunk if
369  * it already has the target profile (even though it may be
370  * half-filled).
371  */
372 #define BTRFS_BALANCE_ARGS_CONVERT	(1ULL << 8)
373 #define BTRFS_BALANCE_ARGS_SOFT		(1ULL << 9)
374 
375 struct btrfs_balance_args;
376 struct btrfs_balance_progress;
377 struct btrfs_balance_control {
378 	struct btrfs_fs_info *fs_info;
379 
380 	struct btrfs_balance_args data;
381 	struct btrfs_balance_args meta;
382 	struct btrfs_balance_args sys;
383 
384 	u64 flags;
385 
386 	struct btrfs_balance_progress stat;
387 };
388 
389 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
390 				   u64 end, u64 *length);
391 
392 #define btrfs_bio_size(total_stripes, real_stripes)		\
393 	(sizeof(struct btrfs_bio) +				\
394 	 (sizeof(struct btrfs_bio_stripe) * (total_stripes)) +	\
395 	 (sizeof(int) * (real_stripes)))
396 
397 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
398 		    u64 logical, u64 *length,
399 		    struct btrfs_bio **bbio_ret, int mirror_num);
400 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, int rw,
401 		     u64 logical, u64 *length,
402 		     struct btrfs_bio **bbio_ret, int mirror_num,
403 		     u64 **raid_map_ret);
404 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
405 		     u64 chunk_start, u64 physical, u64 devid,
406 		     u64 **logical, int *naddrs, int *stripe_len);
407 int btrfs_read_sys_array(struct btrfs_root *root);
408 int btrfs_read_chunk_tree(struct btrfs_root *root);
409 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
410 		      struct btrfs_root *extent_root, u64 type);
411 void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
412 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
413 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
414 		  int mirror_num, int async_submit);
415 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
416 		       fmode_t flags, void *holder);
417 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
418 			  struct btrfs_fs_devices **fs_devices_ret);
419 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
420 void btrfs_close_extra_devices(struct btrfs_fs_info *fs_info,
421 			       struct btrfs_fs_devices *fs_devices, int step);
422 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
423 					 char *device_path,
424 					 struct btrfs_device **device);
425 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
426 					const u64 *devid,
427 					const u8 *uuid);
428 int btrfs_rm_device(struct btrfs_root *root, char *device_path);
429 void btrfs_cleanup_fs_uuids(void);
430 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
431 int btrfs_grow_device(struct btrfs_trans_handle *trans,
432 		      struct btrfs_device *device, u64 new_size);
433 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
434 				       u8 *uuid, u8 *fsid);
435 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
436 int btrfs_init_new_device(struct btrfs_root *root, char *path);
437 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
438 				  struct btrfs_device *srcdev,
439 				  struct btrfs_device **device_out);
440 int btrfs_balance(struct btrfs_balance_control *bctl,
441 		  struct btrfs_ioctl_balance_args *bargs);
442 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
443 int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
444 int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
445 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
446 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
447 int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info);
448 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
449 int find_free_dev_extent(struct btrfs_trans_handle *trans,
450 			 struct btrfs_device *device, u64 num_bytes,
451 			 u64 *start, u64 *max_avail);
452 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
453 int btrfs_get_dev_stats(struct btrfs_root *root,
454 			struct btrfs_ioctl_get_dev_stats *stats);
455 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
456 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
457 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
458 			struct btrfs_fs_info *fs_info);
459 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
460 					struct btrfs_device *srcdev);
461 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
462 				      struct btrfs_device *srcdev);
463 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
464 				      struct btrfs_device *tgtdev);
465 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
466 					      struct btrfs_device *tgtdev);
467 int btrfs_scratch_superblock(struct btrfs_device *device);
468 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
469 			   u64 logical, u64 len, int mirror_num);
470 unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
471 				    struct btrfs_mapping_tree *map_tree,
472 				    u64 logical);
473 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
474 				struct btrfs_root *extent_root,
475 				u64 chunk_offset, u64 chunk_size);
476 int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
477 		       struct btrfs_root *root, u64 chunk_offset);
478 
479 static inline int btrfs_dev_stats_dirty(struct btrfs_device *dev)
480 {
481 	return atomic_read(&dev->dev_stats_ccnt);
482 }
483 
484 static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
485 				      int index)
486 {
487 	atomic_inc(dev->dev_stat_values + index);
488 	smp_mb__before_atomic();
489 	atomic_inc(&dev->dev_stats_ccnt);
490 }
491 
492 static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
493 				      int index)
494 {
495 	return atomic_read(dev->dev_stat_values + index);
496 }
497 
498 static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
499 						int index)
500 {
501 	int ret;
502 
503 	ret = atomic_xchg(dev->dev_stat_values + index, 0);
504 	smp_mb__before_atomic();
505 	atomic_inc(&dev->dev_stats_ccnt);
506 	return ret;
507 }
508 
509 static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
510 				      int index, unsigned long val)
511 {
512 	atomic_set(dev->dev_stat_values + index, val);
513 	smp_mb__before_atomic();
514 	atomic_inc(&dev->dev_stats_ccnt);
515 }
516 
517 static inline void btrfs_dev_stat_reset(struct btrfs_device *dev,
518 					int index)
519 {
520 	btrfs_dev_stat_set(dev, index, 0);
521 }
522 
523 void btrfs_update_commit_device_size(struct btrfs_fs_info *fs_info);
524 void btrfs_update_commit_device_bytes_used(struct btrfs_root *root,
525 					struct btrfs_transaction *transaction);
526 
527 static inline void lock_chunks(struct btrfs_root *root)
528 {
529 	mutex_lock(&root->fs_info->chunk_mutex);
530 }
531 
532 static inline void unlock_chunks(struct btrfs_root *root)
533 {
534 	mutex_unlock(&root->fs_info->chunk_mutex);
535 }
536 
537 
538 #endif
539