1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 md.h : kernel internal structure of the Linux MD driver
4 Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman
5
6 */
7
8 #ifndef _MD_MD_H
9 #define _MD_MD_H
10
11 #include <linux/blkdev.h>
12 #include <linux/backing-dev.h>
13 #include <linux/badblocks.h>
14 #include <linux/kobject.h>
15 #include <linux/list.h>
16 #include <linux/mm.h>
17 #include <linux/mutex.h>
18 #include <linux/timer.h>
19 #include <linux/wait.h>
20 #include <linux/workqueue.h>
21 #include <trace/events/block.h>
22 #include "md-cluster.h"
23
24 #define MaxSector (~(sector_t)0)
25
26 /*
27 * These flags should really be called "NO_RETRY" rather than
28 * "FAILFAST" because they don't make any promise about time lapse,
29 * only about the number of retries, which will be zero.
30 * REQ_FAILFAST_DRIVER is not included because
31 * Commit: 4a27446f3e39 ("[SCSI] modify scsi to handle new fail fast flags.")
32 * seems to suggest that the errors it avoids retrying should usually
33 * be retried.
34 */
35 #define MD_FAILFAST (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT)
36
37 /* Status of sync thread. */
38 enum sync_action {
39 /*
40 * Represent by MD_RECOVERY_SYNC, start when:
41 * 1) after assemble, sync data from first rdev to other copies, this
42 * must be done first before other sync actions and will only execute
43 * once;
44 * 2) resize the array(notice that this is not reshape), sync data for
45 * the new range;
46 */
47 ACTION_RESYNC,
48 /*
49 * Represent by MD_RECOVERY_RECOVER, start when:
50 * 1) for new replacement, sync data based on the replace rdev or
51 * available copies from other rdev;
52 * 2) for new member disk while the array is degraded, sync data from
53 * other rdev;
54 * 3) reassemble after power failure or re-add a hot removed rdev, sync
55 * data from first rdev to other copies based on bitmap;
56 */
57 ACTION_RECOVER,
58 /*
59 * Represent by MD_RECOVERY_SYNC | MD_RECOVERY_REQUESTED |
60 * MD_RECOVERY_CHECK, start when user echo "check" to sysfs api
61 * sync_action, used to check if data copies from differenct rdev are
62 * the same. The number of mismatch sectors will be exported to user
63 * by sysfs api mismatch_cnt;
64 */
65 ACTION_CHECK,
66 /*
67 * Represent by MD_RECOVERY_SYNC | MD_RECOVERY_REQUESTED, start when
68 * user echo "repair" to sysfs api sync_action, usually paired with
69 * ACTION_CHECK, used to force syncing data once user found that there
70 * are inconsistent data,
71 */
72 ACTION_REPAIR,
73 /*
74 * Represent by MD_RECOVERY_RESHAPE, start when new member disk is added
75 * to the conf, notice that this is different from spares or
76 * replacement;
77 */
78 ACTION_RESHAPE,
79 /*
80 * Represent by MD_RECOVERY_FROZEN, can be set by sysfs api sync_action
81 * or internal usage like setting the array read-only, will forbid above
82 * actions.
83 */
84 ACTION_FROZEN,
85 /*
86 * All above actions don't match.
87 */
88 ACTION_IDLE,
89 NR_SYNC_ACTIONS,
90 };
91
92 /*
93 * The struct embedded in rdev is used to serialize IO.
94 */
95 struct serial_in_rdev {
96 struct rb_root_cached serial_rb;
97 spinlock_t serial_lock;
98 wait_queue_head_t serial_io_wait;
99 };
100
101 /*
102 * MD's 'extended' device
103 */
104 struct md_rdev {
105 struct list_head same_set; /* RAID devices within the same set */
106
107 sector_t sectors; /* Device size (in 512bytes sectors) */
108 struct mddev *mddev; /* RAID array if running */
109 int last_events; /* IO event timestamp */
110
111 /*
112 * If meta_bdev is non-NULL, it means that a separate device is
113 * being used to store the metadata (superblock/bitmap) which
114 * would otherwise be contained on the same device as the data (bdev).
115 */
116 struct block_device *meta_bdev;
117 struct block_device *bdev; /* block device handle */
118 struct file *bdev_file; /* Handle from open for bdev */
119
120 struct page *sb_page, *bb_page;
121 int sb_loaded;
122 __u64 sb_events;
123 sector_t data_offset; /* start of data in array */
124 sector_t new_data_offset;/* only relevant while reshaping */
125 sector_t sb_start; /* offset of the super block (in 512byte sectors) */
126 int sb_size; /* bytes in the superblock */
127 int preferred_minor; /* autorun support */
128
129 struct kobject kobj;
130
131 /* A device can be in one of three states based on two flags:
132 * Not working: faulty==1 in_sync==0
133 * Fully working: faulty==0 in_sync==1
134 * Working, but not
135 * in sync with array
136 * faulty==0 in_sync==0
137 *
138 * It can never have faulty==1, in_sync==1
139 * This reduces the burden of testing multiple flags in many cases
140 */
141
142 unsigned long flags; /* bit set of 'enum flag_bits' bits. */
143 wait_queue_head_t blocked_wait;
144
145 int desc_nr; /* descriptor index in the superblock */
146 int raid_disk; /* role of device in array */
147 int new_raid_disk; /* role that the device will have in
148 * the array after a level-change completes.
149 */
150 int saved_raid_disk; /* role that device used to have in the
151 * array and could again if we did a partial
152 * resync from the bitmap
153 */
154 union {
155 sector_t recovery_offset;/* If this device has been partially
156 * recovered, this is where we were
157 * up to.
158 */
159 sector_t journal_tail; /* If this device is a journal device,
160 * this is the journal tail (journal
161 * recovery start point)
162 */
163 };
164
165 atomic_t nr_pending; /* number of pending requests.
166 * only maintained for arrays that
167 * support hot removal
168 */
169 atomic_t read_errors; /* number of consecutive read errors that
170 * we have tried to ignore.
171 */
172 time64_t last_read_error; /* monotonic time since our
173 * last read error
174 */
175 atomic_t corrected_errors; /* number of corrected read errors,
176 * for reporting to userspace and storing
177 * in superblock.
178 */
179
180 struct serial_in_rdev *serial; /* used for raid1 io serialization */
181
182 struct kernfs_node *sysfs_state; /* handle for 'state'
183 * sysfs entry */
184 /* handle for 'unacknowledged_bad_blocks' sysfs dentry */
185 struct kernfs_node *sysfs_unack_badblocks;
186 /* handle for 'bad_blocks' sysfs dentry */
187 struct kernfs_node *sysfs_badblocks;
188 struct badblocks badblocks;
189
190 struct {
191 short offset; /* Offset from superblock to start of PPL.
192 * Not used by external metadata. */
193 unsigned int size; /* Size in sectors of the PPL space */
194 sector_t sector; /* First sector of the PPL space */
195 } ppl;
196 };
197 enum flag_bits {
198 Faulty, /* device is known to have a fault */
199 In_sync, /* device is in_sync with rest of array */
200 Bitmap_sync, /* ..actually, not quite In_sync. Need a
201 * bitmap-based recovery to get fully in sync.
202 * The bit is only meaningful before device
203 * has been passed to pers->hot_add_disk.
204 */
205 WriteMostly, /* Avoid reading if at all possible */
206 AutoDetected, /* added by auto-detect */
207 Blocked, /* An error occurred but has not yet
208 * been acknowledged by the metadata
209 * handler, so don't allow writes
210 * until it is cleared */
211 WriteErrorSeen, /* A write error has been seen on this
212 * device
213 */
214 FaultRecorded, /* Intermediate state for clearing
215 * Blocked. The Fault is/will-be
216 * recorded in the metadata, but that
217 * metadata hasn't been stored safely
218 * on disk yet.
219 */
220 BlockedBadBlocks, /* A writer is blocked because they
221 * found an unacknowledged bad-block.
222 * This can safely be cleared at any
223 * time, and the writer will re-check.
224 * It may be set at any time, and at
225 * worst the writer will timeout and
226 * re-check. So setting it as
227 * accurately as possible is good, but
228 * not absolutely critical.
229 */
230 WantReplacement, /* This device is a candidate to be
231 * hot-replaced, either because it has
232 * reported some faults, or because
233 * of explicit request.
234 */
235 Replacement, /* This device is a replacement for
236 * a want_replacement device with same
237 * raid_disk number.
238 */
239 Candidate, /* For clustered environments only:
240 * This device is seen locally but not
241 * by the whole cluster
242 */
243 Journal, /* This device is used as journal for
244 * raid-5/6.
245 * Usually, this device should be faster
246 * than other devices in the array
247 */
248 ClusterRemove,
249 ExternalBbl, /* External metadata provides bad
250 * block management for a disk
251 */
252 FailFast, /* Minimal retries should be attempted on
253 * this device, so use REQ_FAILFAST_DEV.
254 * Also don't try to repair failed reads.
255 * It is expects that no bad block log
256 * is present.
257 */
258 LastDev, /* Seems to be the last working dev as
259 * it didn't fail, so don't use FailFast
260 * any more for metadata
261 */
262 CollisionCheck, /*
263 * check if there is collision between raid1
264 * serial bios.
265 */
266 Nonrot, /* non-rotational device (SSD) */
267 };
268
is_badblock(struct md_rdev * rdev,sector_t s,int sectors,sector_t * first_bad,int * bad_sectors)269 static inline int is_badblock(struct md_rdev *rdev, sector_t s, int sectors,
270 sector_t *first_bad, int *bad_sectors)
271 {
272 if (unlikely(rdev->badblocks.count)) {
273 int rv = badblocks_check(&rdev->badblocks, rdev->data_offset + s,
274 sectors,
275 first_bad, bad_sectors);
276 if (rv)
277 *first_bad -= rdev->data_offset;
278 return rv;
279 }
280 return 0;
281 }
282
rdev_has_badblock(struct md_rdev * rdev,sector_t s,int sectors)283 static inline int rdev_has_badblock(struct md_rdev *rdev, sector_t s,
284 int sectors)
285 {
286 sector_t first_bad;
287 int bad_sectors;
288
289 return is_badblock(rdev, s, sectors, &first_bad, &bad_sectors);
290 }
291
292 extern int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
293 int is_new);
294 extern int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
295 int is_new);
296 struct md_cluster_info;
297
298 /**
299 * enum mddev_flags - md device flags.
300 * @MD_ARRAY_FIRST_USE: First use of array, needs initialization.
301 * @MD_CLOSING: If set, we are closing the array, do not open it then.
302 * @MD_JOURNAL_CLEAN: A raid with journal is already clean.
303 * @MD_HAS_JOURNAL: The raid array has journal feature set.
304 * @MD_CLUSTER_RESYNC_LOCKED: cluster raid only, which means node, already took
305 * resync lock, need to release the lock.
306 * @MD_FAILFAST_SUPPORTED: Using MD_FAILFAST on metadata writes is supported as
307 * calls to md_error() will never cause the array to
308 * become failed.
309 * @MD_HAS_PPL: The raid array has PPL feature set.
310 * @MD_HAS_MULTIPLE_PPLS: The raid array has multiple PPLs feature set.
311 * @MD_NOT_READY: do_md_run() is active, so 'array_state', ust not report that
312 * array is ready yet.
313 * @MD_BROKEN: This is used to stop writes and mark array as failed.
314 * @MD_DELETED: This device is being deleted
315 *
316 * change UNSUPPORTED_MDDEV_FLAGS for each array type if new flag is added
317 */
318 enum mddev_flags {
319 MD_ARRAY_FIRST_USE,
320 MD_CLOSING,
321 MD_JOURNAL_CLEAN,
322 MD_HAS_JOURNAL,
323 MD_CLUSTER_RESYNC_LOCKED,
324 MD_FAILFAST_SUPPORTED,
325 MD_HAS_PPL,
326 MD_HAS_MULTIPLE_PPLS,
327 MD_NOT_READY,
328 MD_BROKEN,
329 MD_DELETED,
330 };
331
332 enum mddev_sb_flags {
333 MD_SB_CHANGE_DEVS, /* Some device status has changed */
334 MD_SB_CHANGE_CLEAN, /* transition to or from 'clean' */
335 MD_SB_CHANGE_PENDING, /* switch from 'clean' to 'active' in progress */
336 MD_SB_NEED_REWRITE, /* metadata write needs to be repeated */
337 };
338
339 #define NR_SERIAL_INFOS 8
340 /* record current range of serialize IOs */
341 struct serial_info {
342 struct rb_node node;
343 sector_t start; /* start sector of rb node */
344 sector_t last; /* end sector of rb node */
345 sector_t _subtree_last; /* highest sector in subtree of rb node */
346 };
347
348 /*
349 * mddev->curr_resync stores the current sector of the resync but
350 * also has some overloaded values.
351 */
352 enum {
353 /* No resync in progress */
354 MD_RESYNC_NONE = 0,
355 /* Yielded to allow another conflicting resync to commence */
356 MD_RESYNC_YIELDED = 1,
357 /* Delayed to check that there is no conflict with another sync */
358 MD_RESYNC_DELAYED = 2,
359 /* Any value greater than or equal to this is in an active resync */
360 MD_RESYNC_ACTIVE = 3,
361 };
362
363 struct mddev {
364 void *private;
365 struct md_personality *pers;
366 dev_t unit;
367 int md_minor;
368 struct list_head disks;
369 unsigned long flags;
370 unsigned long sb_flags;
371
372 int suspended;
373 struct mutex suspend_mutex;
374 struct percpu_ref active_io;
375 int ro;
376 int sysfs_active; /* set when sysfs deletes
377 * are happening, so run/
378 * takeover/stop are not safe
379 */
380 struct gendisk *gendisk;
381
382 struct kobject kobj;
383 int hold_active;
384 #define UNTIL_IOCTL 1
385 #define UNTIL_STOP 2
386
387 /* Superblock information */
388 int major_version,
389 minor_version,
390 patch_version;
391 int persistent;
392 int external; /* metadata is
393 * managed externally */
394 char metadata_type[17]; /* externally set*/
395 int chunk_sectors;
396 time64_t ctime, utime;
397 int level, layout;
398 char clevel[16];
399 int raid_disks;
400 int max_disks;
401 sector_t dev_sectors; /* used size of
402 * component devices */
403 sector_t array_sectors; /* exported array size */
404 int external_size; /* size managed
405 * externally */
406 __u64 events;
407 /* If the last 'event' was simply a clean->dirty transition, and
408 * we didn't write it to the spares, then it is safe and simple
409 * to just decrement the event count on a dirty->clean transition.
410 * So we record that possibility here.
411 */
412 int can_decrease_events;
413
414 char uuid[16];
415
416 /* If the array is being reshaped, we need to record the
417 * new shape and an indication of where we are up to.
418 * This is written to the superblock.
419 * If reshape_position is MaxSector, then no reshape is happening (yet).
420 */
421 sector_t reshape_position;
422 int delta_disks, new_level, new_layout;
423 int new_chunk_sectors;
424 int reshape_backwards;
425
426 struct md_thread __rcu *thread; /* management thread */
427 struct md_thread __rcu *sync_thread; /* doing resync or reconstruct */
428
429 /*
430 * Set when a sync operation is started. It holds this value even
431 * when the sync thread is "frozen" (interrupted) or "idle" (stopped
432 * or finished). It is overwritten when a new sync operation is begun.
433 */
434 enum sync_action last_sync_action;
435 sector_t curr_resync; /* last block scheduled */
436 /* As resync requests can complete out of order, we cannot easily track
437 * how much resync has been completed. So we occasionally pause until
438 * everything completes, then set curr_resync_completed to curr_resync.
439 * As such it may be well behind the real resync mark, but it is a value
440 * we are certain of.
441 */
442 sector_t curr_resync_completed;
443 unsigned long resync_mark; /* a recent timestamp */
444 sector_t resync_mark_cnt;/* blocks written at resync_mark */
445 sector_t curr_mark_cnt; /* blocks scheduled now */
446
447 sector_t resync_max_sectors; /* may be set by personality */
448
449 atomic64_t resync_mismatches; /* count of sectors where
450 * parity/replica mismatch found
451 */
452
453 /* allow user-space to request suspension of IO to regions of the array */
454 sector_t suspend_lo;
455 sector_t suspend_hi;
456 /* if zero, use the system-wide default */
457 int sync_speed_min;
458 int sync_speed_max;
459
460 /* resync even though the same disks are shared among md-devices */
461 int parallel_resync;
462
463 int ok_start_degraded;
464
465 unsigned long recovery;
466 /* If a RAID personality determines that recovery (of a particular
467 * device) will fail due to a read error on the source device, it
468 * takes a copy of this number and does not attempt recovery again
469 * until this number changes.
470 */
471 int recovery_disabled;
472
473 int in_sync; /* know to not need resync */
474 /* 'open_mutex' avoids races between 'md_open' and 'do_md_stop', so
475 * that we are never stopping an array while it is open.
476 * 'reconfig_mutex' protects all other reconfiguration.
477 * These locks are separate due to conflicting interactions
478 * with disk->open_mutex.
479 * Lock ordering is:
480 * reconfig_mutex -> disk->open_mutex
481 * disk->open_mutex -> open_mutex: e.g. __blkdev_get -> md_open
482 */
483 struct mutex open_mutex;
484 struct mutex reconfig_mutex;
485 atomic_t active; /* general refcount */
486 atomic_t openers; /* number of active opens */
487
488 int changed; /* True if we might need to
489 * reread partition info */
490 int degraded; /* whether md should consider
491 * adding a spare
492 */
493
494 atomic_t recovery_active; /* blocks scheduled, but not written */
495 wait_queue_head_t recovery_wait;
496 sector_t recovery_cp;
497 sector_t resync_min; /* user requested sync
498 * starts here */
499 sector_t resync_max; /* resync should pause
500 * when it gets here */
501
502 struct kernfs_node *sysfs_state; /* handle for 'array_state'
503 * file in sysfs.
504 */
505 struct kernfs_node *sysfs_action; /* handle for 'sync_action' */
506 struct kernfs_node *sysfs_completed; /*handle for 'sync_completed' */
507 struct kernfs_node *sysfs_degraded; /*handle for 'degraded' */
508 struct kernfs_node *sysfs_level; /*handle for 'level' */
509
510 /* used for delayed sysfs removal */
511 struct work_struct del_work;
512 /* used for register new sync thread */
513 struct work_struct sync_work;
514
515 /* "lock" protects:
516 * flush_bio transition from NULL to !NULL
517 * rdev superblocks, events
518 * clearing MD_CHANGE_*
519 * in_sync - and related safemode and MD_CHANGE changes
520 * pers (also protected by reconfig_mutex and pending IO).
521 * clearing ->bitmap
522 * clearing ->bitmap_info.file
523 * changing ->resync_{min,max}
524 * setting MD_RECOVERY_RUNNING (which interacts with resync_{min,max})
525 */
526 spinlock_t lock;
527 wait_queue_head_t sb_wait; /* for waiting on superblock updates */
528 atomic_t pending_writes; /* number of active superblock writes */
529
530 unsigned int safemode; /* if set, update "clean" superblock
531 * when no writes pending.
532 */
533 unsigned int safemode_delay;
534 struct timer_list safemode_timer;
535 struct percpu_ref writes_pending;
536 int sync_checkers; /* # of threads checking writes_pending */
537
538 void *bitmap; /* the bitmap for the device */
539 struct bitmap_operations *bitmap_ops;
540 struct {
541 struct file *file; /* the bitmap file */
542 loff_t offset; /* offset from superblock of
543 * start of bitmap. May be
544 * negative, but not '0'
545 * For external metadata, offset
546 * from start of device.
547 */
548 unsigned long space; /* space available at this offset */
549 loff_t default_offset; /* this is the offset to use when
550 * hot-adding a bitmap. It should
551 * eventually be settable by sysfs.
552 */
553 unsigned long default_space; /* space available at
554 * default offset */
555 struct mutex mutex;
556 unsigned long chunksize;
557 unsigned long daemon_sleep; /* how many jiffies between updates? */
558 unsigned long max_write_behind; /* write-behind mode */
559 int external;
560 int nodes; /* Maximum number of nodes in the cluster */
561 char cluster_name[64]; /* Name of the cluster */
562 } bitmap_info;
563
564 atomic_t max_corr_read_errors; /* max read retries */
565 struct list_head all_mddevs;
566
567 const struct attribute_group *to_remove;
568
569 struct bio_set bio_set;
570 struct bio_set sync_set; /* for sync operations like
571 * metadata and bitmap writes
572 */
573 struct bio_set io_clone_set;
574
575 struct work_struct event_work; /* used by dm to report failure event */
576 mempool_t *serial_info_pool;
577 void (*sync_super)(struct mddev *mddev, struct md_rdev *rdev);
578 struct md_cluster_info *cluster_info;
579 unsigned int good_device_nr; /* good device num within cluster raid */
580 unsigned int noio_flag; /* for memalloc scope API */
581
582 /*
583 * Temporarily store rdev that will be finally removed when
584 * reconfig_mutex is unlocked, protected by reconfig_mutex.
585 */
586 struct list_head deleting;
587
588 /* The sequence number for sync thread */
589 atomic_t sync_seq;
590
591 bool has_superblocks:1;
592 bool fail_last_dev:1;
593 bool serialize_policy:1;
594 };
595
596 enum recovery_flags {
597 /* flags for sync thread running status */
598
599 /*
600 * set when one of sync action is set and new sync thread need to be
601 * registered, or just add/remove spares from conf.
602 */
603 MD_RECOVERY_NEEDED,
604 /* sync thread is running, or about to be started */
605 MD_RECOVERY_RUNNING,
606 /* sync thread needs to be aborted for some reason */
607 MD_RECOVERY_INTR,
608 /* sync thread is done and is waiting to be unregistered */
609 MD_RECOVERY_DONE,
610 /* running sync thread must abort immediately, and not restart */
611 MD_RECOVERY_FROZEN,
612 /* waiting for pers->start() to finish */
613 MD_RECOVERY_WAIT,
614 /* interrupted because io-error */
615 MD_RECOVERY_ERROR,
616
617 /* flags determines sync action, see details in enum sync_action */
618
619 /* if just this flag is set, action is resync. */
620 MD_RECOVERY_SYNC,
621 /*
622 * paired with MD_RECOVERY_SYNC, if MD_RECOVERY_CHECK is not set,
623 * action is repair, means user requested resync.
624 */
625 MD_RECOVERY_REQUESTED,
626 /*
627 * paired with MD_RECOVERY_SYNC and MD_RECOVERY_REQUESTED, action is
628 * check.
629 */
630 MD_RECOVERY_CHECK,
631 /* recovery, or need to try it */
632 MD_RECOVERY_RECOVER,
633 /* reshape */
634 MD_RECOVERY_RESHAPE,
635 /* remote node is running resync thread */
636 MD_RESYNCING_REMOTE,
637 };
638
639 enum md_ro_state {
640 MD_RDWR,
641 MD_RDONLY,
642 MD_AUTO_READ,
643 MD_MAX_STATE
644 };
645
md_is_rdwr(struct mddev * mddev)646 static inline bool md_is_rdwr(struct mddev *mddev)
647 {
648 return (mddev->ro == MD_RDWR);
649 }
650
reshape_interrupted(struct mddev * mddev)651 static inline bool reshape_interrupted(struct mddev *mddev)
652 {
653 /* reshape never start */
654 if (mddev->reshape_position == MaxSector)
655 return false;
656
657 /* interrupted */
658 if (!test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
659 return true;
660
661 /* running reshape will be interrupted soon. */
662 if (test_bit(MD_RECOVERY_WAIT, &mddev->recovery) ||
663 test_bit(MD_RECOVERY_INTR, &mddev->recovery) ||
664 test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
665 return true;
666
667 return false;
668 }
669
mddev_lock(struct mddev * mddev)670 static inline int __must_check mddev_lock(struct mddev *mddev)
671 {
672 return mutex_lock_interruptible(&mddev->reconfig_mutex);
673 }
674
675 /* Sometimes we need to take the lock in a situation where
676 * failure due to interrupts is not acceptable.
677 */
mddev_lock_nointr(struct mddev * mddev)678 static inline void mddev_lock_nointr(struct mddev *mddev)
679 {
680 mutex_lock(&mddev->reconfig_mutex);
681 }
682
mddev_trylock(struct mddev * mddev)683 static inline int mddev_trylock(struct mddev *mddev)
684 {
685 return mutex_trylock(&mddev->reconfig_mutex);
686 }
687 extern void mddev_unlock(struct mddev *mddev);
688
md_sync_acct(struct block_device * bdev,unsigned long nr_sectors)689 static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors)
690 {
691 if (blk_queue_io_stat(bdev->bd_disk->queue))
692 atomic_add(nr_sectors, &bdev->bd_disk->sync_io);
693 }
694
md_sync_acct_bio(struct bio * bio,unsigned long nr_sectors)695 static inline void md_sync_acct_bio(struct bio *bio, unsigned long nr_sectors)
696 {
697 md_sync_acct(bio->bi_bdev, nr_sectors);
698 }
699
700 struct md_personality
701 {
702 char *name;
703 int level;
704 struct list_head list;
705 struct module *owner;
706 bool __must_check (*make_request)(struct mddev *mddev, struct bio *bio);
707 /*
708 * start up works that do NOT require md_thread. tasks that
709 * requires md_thread should go into start()
710 */
711 int (*run)(struct mddev *mddev);
712 /* start up works that require md threads */
713 int (*start)(struct mddev *mddev);
714 void (*free)(struct mddev *mddev, void *priv);
715 void (*status)(struct seq_file *seq, struct mddev *mddev);
716 /* error_handler must set ->faulty and clear ->in_sync
717 * if appropriate, and should abort recovery if needed
718 */
719 void (*error_handler)(struct mddev *mddev, struct md_rdev *rdev);
720 int (*hot_add_disk) (struct mddev *mddev, struct md_rdev *rdev);
721 int (*hot_remove_disk) (struct mddev *mddev, struct md_rdev *rdev);
722 int (*spare_active) (struct mddev *mddev);
723 sector_t (*sync_request)(struct mddev *mddev, sector_t sector_nr,
724 sector_t max_sector, int *skipped);
725 int (*resize) (struct mddev *mddev, sector_t sectors);
726 sector_t (*size) (struct mddev *mddev, sector_t sectors, int raid_disks);
727 int (*check_reshape) (struct mddev *mddev);
728 int (*start_reshape) (struct mddev *mddev);
729 void (*finish_reshape) (struct mddev *mddev);
730 void (*update_reshape_pos) (struct mddev *mddev);
731 void (*prepare_suspend) (struct mddev *mddev);
732 /* quiesce suspends or resumes internal processing.
733 * 1 - stop new actions and wait for action io to complete
734 * 0 - return to normal behaviour
735 */
736 void (*quiesce) (struct mddev *mddev, int quiesce);
737 /* takeover is used to transition an array from one
738 * personality to another. The new personality must be able
739 * to handle the data in the current layout.
740 * e.g. 2drive raid1 -> 2drive raid5
741 * ndrive raid5 -> degraded n+1drive raid6 with special layout
742 * If the takeover succeeds, a new 'private' structure is returned.
743 * This needs to be installed and then ->run used to activate the
744 * array.
745 */
746 void *(*takeover) (struct mddev *mddev);
747 /* Changes the consistency policy of an active array. */
748 int (*change_consistency_policy)(struct mddev *mddev, const char *buf);
749 };
750
751 struct md_sysfs_entry {
752 struct attribute attr;
753 ssize_t (*show)(struct mddev *, char *);
754 ssize_t (*store)(struct mddev *, const char *, size_t);
755 };
756 extern const struct attribute_group md_bitmap_group;
757
sysfs_get_dirent_safe(struct kernfs_node * sd,char * name)758 static inline struct kernfs_node *sysfs_get_dirent_safe(struct kernfs_node *sd, char *name)
759 {
760 if (sd)
761 return sysfs_get_dirent(sd, name);
762 return sd;
763 }
sysfs_notify_dirent_safe(struct kernfs_node * sd)764 static inline void sysfs_notify_dirent_safe(struct kernfs_node *sd)
765 {
766 if (sd)
767 sysfs_notify_dirent(sd);
768 }
769
mdname(struct mddev * mddev)770 static inline char * mdname (struct mddev * mddev)
771 {
772 return mddev->gendisk ? mddev->gendisk->disk_name : "mdX";
773 }
774
sysfs_link_rdev(struct mddev * mddev,struct md_rdev * rdev)775 static inline int sysfs_link_rdev(struct mddev *mddev, struct md_rdev *rdev)
776 {
777 char nm[20];
778 if (!test_bit(Replacement, &rdev->flags) &&
779 !test_bit(Journal, &rdev->flags) &&
780 mddev->kobj.sd) {
781 sprintf(nm, "rd%d", rdev->raid_disk);
782 return sysfs_create_link(&mddev->kobj, &rdev->kobj, nm);
783 } else
784 return 0;
785 }
786
sysfs_unlink_rdev(struct mddev * mddev,struct md_rdev * rdev)787 static inline void sysfs_unlink_rdev(struct mddev *mddev, struct md_rdev *rdev)
788 {
789 char nm[20];
790 if (!test_bit(Replacement, &rdev->flags) &&
791 !test_bit(Journal, &rdev->flags) &&
792 mddev->kobj.sd) {
793 sprintf(nm, "rd%d", rdev->raid_disk);
794 sysfs_remove_link(&mddev->kobj, nm);
795 }
796 }
797
798 /*
799 * iterates through some rdev ringlist. It's safe to remove the
800 * current 'rdev'. Dont touch 'tmp' though.
801 */
802 #define rdev_for_each_list(rdev, tmp, head) \
803 list_for_each_entry_safe(rdev, tmp, head, same_set)
804
805 /*
806 * iterates through the 'same array disks' ringlist
807 */
808 #define rdev_for_each(rdev, mddev) \
809 list_for_each_entry(rdev, &((mddev)->disks), same_set)
810
811 #define rdev_for_each_safe(rdev, tmp, mddev) \
812 list_for_each_entry_safe(rdev, tmp, &((mddev)->disks), same_set)
813
814 #define rdev_for_each_rcu(rdev, mddev) \
815 list_for_each_entry_rcu(rdev, &((mddev)->disks), same_set)
816
817 struct md_thread {
818 void (*run) (struct md_thread *thread);
819 struct mddev *mddev;
820 wait_queue_head_t wqueue;
821 unsigned long flags;
822 struct task_struct *tsk;
823 unsigned long timeout;
824 void *private;
825 };
826
827 struct md_io_clone {
828 struct mddev *mddev;
829 struct bio *orig_bio;
830 unsigned long start_time;
831 struct bio bio_clone;
832 };
833
834 #define THREAD_WAKEUP 0
835
safe_put_page(struct page * p)836 static inline void safe_put_page(struct page *p)
837 {
838 if (p) put_page(p);
839 }
840
841 extern int register_md_personality(struct md_personality *p);
842 extern int unregister_md_personality(struct md_personality *p);
843 extern int register_md_cluster_operations(const struct md_cluster_operations *ops,
844 struct module *module);
845 extern int unregister_md_cluster_operations(void);
846 extern int md_setup_cluster(struct mddev *mddev, int nodes);
847 extern void md_cluster_stop(struct mddev *mddev);
848 extern struct md_thread *md_register_thread(
849 void (*run)(struct md_thread *thread),
850 struct mddev *mddev,
851 const char *name);
852 extern void md_unregister_thread(struct mddev *mddev, struct md_thread __rcu **threadp);
853 extern void md_wakeup_thread(struct md_thread __rcu *thread);
854 extern void md_check_recovery(struct mddev *mddev);
855 extern void md_reap_sync_thread(struct mddev *mddev);
856 extern enum sync_action md_sync_action(struct mddev *mddev);
857 extern enum sync_action md_sync_action_by_name(const char *page);
858 extern const char *md_sync_action_name(enum sync_action action);
859 extern void md_write_start(struct mddev *mddev, struct bio *bi);
860 extern void md_write_inc(struct mddev *mddev, struct bio *bi);
861 extern void md_write_end(struct mddev *mddev);
862 extern void md_done_sync(struct mddev *mddev, int blocks, int ok);
863 extern void md_error(struct mddev *mddev, struct md_rdev *rdev);
864 extern void md_finish_reshape(struct mddev *mddev);
865 void md_submit_discard_bio(struct mddev *mddev, struct md_rdev *rdev,
866 struct bio *bio, sector_t start, sector_t size);
867 void md_account_bio(struct mddev *mddev, struct bio **bio);
868 void md_free_cloned_bio(struct bio *bio);
869
870 extern bool __must_check md_flush_request(struct mddev *mddev, struct bio *bio);
871 extern void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
872 sector_t sector, int size, struct page *page);
873 extern int md_super_wait(struct mddev *mddev);
874 extern int sync_page_io(struct md_rdev *rdev, sector_t sector, int size,
875 struct page *page, blk_opf_t opf, bool metadata_op);
876 extern void md_do_sync(struct md_thread *thread);
877 extern void md_new_event(void);
878 extern void md_allow_write(struct mddev *mddev);
879 extern void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev);
880 extern void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors);
881 extern int md_check_no_bitmap(struct mddev *mddev);
882 extern int md_integrity_register(struct mddev *mddev);
883 extern int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale);
884
885 extern int mddev_init(struct mddev *mddev);
886 extern void mddev_destroy(struct mddev *mddev);
887 void md_init_stacking_limits(struct queue_limits *lim);
888 struct mddev *md_alloc(dev_t dev, char *name);
889 void mddev_put(struct mddev *mddev);
890 extern int md_run(struct mddev *mddev);
891 extern int md_start(struct mddev *mddev);
892 extern void md_stop(struct mddev *mddev);
893 extern void md_stop_writes(struct mddev *mddev);
894 extern int md_rdev_init(struct md_rdev *rdev);
895 extern void md_rdev_clear(struct md_rdev *rdev);
896
897 extern bool md_handle_request(struct mddev *mddev, struct bio *bio);
898 extern int mddev_suspend(struct mddev *mddev, bool interruptible);
899 extern void mddev_resume(struct mddev *mddev);
900 extern void md_idle_sync_thread(struct mddev *mddev);
901 extern void md_frozen_sync_thread(struct mddev *mddev);
902 extern void md_unfrozen_sync_thread(struct mddev *mddev);
903
904 extern void md_reload_sb(struct mddev *mddev, int raid_disk);
905 extern void md_update_sb(struct mddev *mddev, int force);
906 extern void mddev_create_serial_pool(struct mddev *mddev, struct md_rdev *rdev);
907 extern void mddev_destroy_serial_pool(struct mddev *mddev,
908 struct md_rdev *rdev);
909 struct md_rdev *md_find_rdev_nr_rcu(struct mddev *mddev, int nr);
910 struct md_rdev *md_find_rdev_rcu(struct mddev *mddev, dev_t dev);
911
is_rdev_broken(struct md_rdev * rdev)912 static inline bool is_rdev_broken(struct md_rdev *rdev)
913 {
914 return !disk_live(rdev->bdev->bd_disk);
915 }
916
rdev_dec_pending(struct md_rdev * rdev,struct mddev * mddev)917 static inline void rdev_dec_pending(struct md_rdev *rdev, struct mddev *mddev)
918 {
919 int faulty = test_bit(Faulty, &rdev->flags);
920 if (atomic_dec_and_test(&rdev->nr_pending) && faulty) {
921 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
922 md_wakeup_thread(mddev->thread);
923 }
924 }
925
926 extern const struct md_cluster_operations *md_cluster_ops;
mddev_is_clustered(struct mddev * mddev)927 static inline int mddev_is_clustered(struct mddev *mddev)
928 {
929 return mddev->cluster_info && mddev->bitmap_info.nodes > 1;
930 }
931
932 /* clear unsupported mddev_flags */
mddev_clear_unsupported_flags(struct mddev * mddev,unsigned long unsupported_flags)933 static inline void mddev_clear_unsupported_flags(struct mddev *mddev,
934 unsigned long unsupported_flags)
935 {
936 mddev->flags &= ~unsupported_flags;
937 }
938
mddev_check_write_zeroes(struct mddev * mddev,struct bio * bio)939 static inline void mddev_check_write_zeroes(struct mddev *mddev, struct bio *bio)
940 {
941 if (bio_op(bio) == REQ_OP_WRITE_ZEROES &&
942 !bio->bi_bdev->bd_disk->queue->limits.max_write_zeroes_sectors)
943 mddev->gendisk->queue->limits.max_write_zeroes_sectors = 0;
944 }
945
mddev_suspend_and_lock(struct mddev * mddev)946 static inline int mddev_suspend_and_lock(struct mddev *mddev)
947 {
948 int ret;
949
950 ret = mddev_suspend(mddev, true);
951 if (ret)
952 return ret;
953
954 ret = mddev_lock(mddev);
955 if (ret)
956 mddev_resume(mddev);
957
958 return ret;
959 }
960
mddev_suspend_and_lock_nointr(struct mddev * mddev)961 static inline void mddev_suspend_and_lock_nointr(struct mddev *mddev)
962 {
963 mddev_suspend(mddev, false);
964 mutex_lock(&mddev->reconfig_mutex);
965 }
966
mddev_unlock_and_resume(struct mddev * mddev)967 static inline void mddev_unlock_and_resume(struct mddev *mddev)
968 {
969 mddev_unlock(mddev);
970 mddev_resume(mddev);
971 }
972
973 struct mdu_array_info_s;
974 struct mdu_disk_info_s;
975
976 extern int mdp_major;
977 extern struct workqueue_struct *md_bitmap_wq;
978 void md_autostart_arrays(int part);
979 int md_set_array_info(struct mddev *mddev, struct mdu_array_info_s *info);
980 int md_add_new_disk(struct mddev *mddev, struct mdu_disk_info_s *info);
981 int do_md_run(struct mddev *mddev);
982 #define MDDEV_STACK_INTEGRITY (1u << 0)
983 int mddev_stack_rdev_limits(struct mddev *mddev, struct queue_limits *lim,
984 unsigned int flags);
985 int mddev_stack_new_rdev(struct mddev *mddev, struct md_rdev *rdev);
986 void mddev_update_io_opt(struct mddev *mddev, unsigned int nr_stripes);
987
988 extern const struct block_device_operations md_fops;
989
990 /*
991 * MD devices can be used undeneath by DM, in which case ->gendisk is NULL.
992 */
mddev_is_dm(struct mddev * mddev)993 static inline bool mddev_is_dm(struct mddev *mddev)
994 {
995 return !mddev->gendisk;
996 }
997
mddev_trace_remap(struct mddev * mddev,struct bio * bio,sector_t sector)998 static inline void mddev_trace_remap(struct mddev *mddev, struct bio *bio,
999 sector_t sector)
1000 {
1001 if (!mddev_is_dm(mddev))
1002 trace_block_bio_remap(bio, disk_devt(mddev->gendisk), sector);
1003 }
1004
rdev_blocked(struct md_rdev * rdev)1005 static inline bool rdev_blocked(struct md_rdev *rdev)
1006 {
1007 /*
1008 * Blocked will be set by error handler and cleared by daemon after
1009 * updating superblock, meanwhile write IO should be blocked to prevent
1010 * reading old data after power failure.
1011 */
1012 if (test_bit(Blocked, &rdev->flags))
1013 return true;
1014
1015 /*
1016 * Faulty device should not be accessed anymore, there is no need to
1017 * wait for bad block to be acknowledged.
1018 */
1019 if (test_bit(Faulty, &rdev->flags))
1020 return false;
1021
1022 /* rdev is blocked by badblocks. */
1023 if (test_bit(BlockedBadBlocks, &rdev->flags))
1024 return true;
1025
1026 return false;
1027 }
1028
1029 #define mddev_add_trace_msg(mddev, fmt, args...) \
1030 do { \
1031 if (!mddev_is_dm(mddev)) \
1032 blk_add_trace_msg((mddev)->gendisk->queue, fmt, ##args); \
1033 } while (0)
1034
1035 #endif /* _MD_MD_H */
1036