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 <linux/raid/md_u.h>
22 #include <trace/events/block.h>
23
24 #define MaxSector (~(sector_t)0)
25
26 enum md_submodule_type {
27 MD_PERSONALITY = 0,
28 MD_CLUSTER,
29 MD_BITMAP, /* TODO */
30 };
31
32 enum md_submodule_id {
33 ID_LINEAR = LEVEL_LINEAR,
34 ID_RAID0 = 0,
35 ID_RAID1 = 1,
36 ID_RAID4 = 4,
37 ID_RAID5 = 5,
38 ID_RAID6 = 6,
39 ID_RAID10 = 10,
40 ID_CLUSTER,
41 ID_BITMAP, /* TODO */
42 ID_LLBITMAP, /* TODO */
43 };
44
45 struct md_submodule_head {
46 enum md_submodule_type type;
47 enum md_submodule_id id;
48 const char *name;
49 struct module *owner;
50 };
51
52 /*
53 * These flags should really be called "NO_RETRY" rather than
54 * "FAILFAST" because they don't make any promise about time lapse,
55 * only about the number of retries, which will be zero.
56 * REQ_FAILFAST_DRIVER is not included because
57 * Commit: 4a27446f3e39 ("[SCSI] modify scsi to handle new fail fast flags.")
58 * seems to suggest that the errors it avoids retrying should usually
59 * be retried.
60 */
61 #define MD_FAILFAST (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT)
62
63 /* Status of sync thread. */
64 enum sync_action {
65 /*
66 * Represent by MD_RECOVERY_SYNC, start when:
67 * 1) after assemble, sync data from first rdev to other copies, this
68 * must be done first before other sync actions and will only execute
69 * once;
70 * 2) resize the array(notice that this is not reshape), sync data for
71 * the new range;
72 */
73 ACTION_RESYNC,
74 /*
75 * Represent by MD_RECOVERY_RECOVER, start when:
76 * 1) for new replacement, sync data based on the replace rdev or
77 * available copies from other rdev;
78 * 2) for new member disk while the array is degraded, sync data from
79 * other rdev;
80 * 3) reassemble after power failure or re-add a hot removed rdev, sync
81 * data from first rdev to other copies based on bitmap;
82 */
83 ACTION_RECOVER,
84 /*
85 * Represent by MD_RECOVERY_SYNC | MD_RECOVERY_REQUESTED |
86 * MD_RECOVERY_CHECK, start when user echo "check" to sysfs api
87 * sync_action, used to check if data copies from differenct rdev are
88 * the same. The number of mismatch sectors will be exported to user
89 * by sysfs api mismatch_cnt;
90 */
91 ACTION_CHECK,
92 /*
93 * Represent by MD_RECOVERY_SYNC | MD_RECOVERY_REQUESTED, start when
94 * user echo "repair" to sysfs api sync_action, usually paired with
95 * ACTION_CHECK, used to force syncing data once user found that there
96 * are inconsistent data,
97 */
98 ACTION_REPAIR,
99 /*
100 * Represent by MD_RECOVERY_RESHAPE, start when new member disk is added
101 * to the conf, notice that this is different from spares or
102 * replacement;
103 */
104 ACTION_RESHAPE,
105 /*
106 * Represent by MD_RECOVERY_FROZEN, can be set by sysfs api sync_action
107 * or internal usage like setting the array read-only, will forbid above
108 * actions.
109 */
110 ACTION_FROZEN,
111 /*
112 * All above actions don't match.
113 */
114 ACTION_IDLE,
115 NR_SYNC_ACTIONS,
116 };
117
118 /*
119 * The struct embedded in rdev is used to serialize IO.
120 */
121 struct serial_in_rdev {
122 struct rb_root_cached serial_rb;
123 spinlock_t serial_lock;
124 wait_queue_head_t serial_io_wait;
125 };
126
127 /*
128 * MD's 'extended' device
129 */
130 struct md_rdev {
131 struct list_head same_set; /* RAID devices within the same set */
132
133 sector_t sectors; /* Device size (in 512bytes sectors) */
134 struct mddev *mddev; /* RAID array if running */
135 unsigned long last_events; /* IO event timestamp */
136
137 /*
138 * If meta_bdev is non-NULL, it means that a separate device is
139 * being used to store the metadata (superblock/bitmap) which
140 * would otherwise be contained on the same device as the data (bdev).
141 */
142 struct block_device *meta_bdev;
143 struct block_device *bdev; /* block device handle */
144 struct file *bdev_file; /* Handle from open for bdev */
145
146 struct page *sb_page, *bb_page;
147 int sb_loaded;
148 __u64 sb_events;
149 sector_t data_offset; /* start of data in array */
150 sector_t new_data_offset;/* only relevant while reshaping */
151 sector_t sb_start; /* offset of the super block (in 512byte sectors) */
152 int sb_size; /* bytes in the superblock */
153 int preferred_minor; /* autorun support */
154
155 struct kobject kobj;
156
157 /* A device can be in one of three states based on two flags:
158 * Not working: faulty==1 in_sync==0
159 * Fully working: faulty==0 in_sync==1
160 * Working, but not
161 * in sync with array
162 * faulty==0 in_sync==0
163 *
164 * It can never have faulty==1, in_sync==1
165 * This reduces the burden of testing multiple flags in many cases
166 */
167
168 unsigned long flags; /* bit set of 'enum flag_bits' bits. */
169 wait_queue_head_t blocked_wait;
170
171 int desc_nr; /* descriptor index in the superblock */
172 int raid_disk; /* role of device in array */
173 int new_raid_disk; /* role that the device will have in
174 * the array after a level-change completes.
175 */
176 int saved_raid_disk; /* role that device used to have in the
177 * array and could again if we did a partial
178 * resync from the bitmap
179 */
180 union {
181 sector_t recovery_offset;/* If this device has been partially
182 * recovered, this is where we were
183 * up to.
184 */
185 sector_t journal_tail; /* If this device is a journal device,
186 * this is the journal tail (journal
187 * recovery start point)
188 */
189 };
190
191 atomic_t nr_pending; /* number of pending requests.
192 * only maintained for arrays that
193 * support hot removal
194 */
195 atomic_t read_errors; /* number of consecutive read errors that
196 * we have tried to ignore.
197 */
198 time64_t last_read_error; /* monotonic time since our
199 * last read error
200 */
201 atomic_t corrected_errors; /* number of corrected read errors,
202 * for reporting to userspace and storing
203 * in superblock.
204 */
205
206 struct serial_in_rdev *serial; /* used for raid1 io serialization */
207
208 struct kernfs_node *sysfs_state; /* handle for 'state'
209 * sysfs entry */
210 /* handle for 'unacknowledged_bad_blocks' sysfs dentry */
211 struct kernfs_node *sysfs_unack_badblocks;
212 /* handle for 'bad_blocks' sysfs dentry */
213 struct kernfs_node *sysfs_badblocks;
214 struct badblocks badblocks;
215
216 struct {
217 short offset; /* Offset from superblock to start of PPL.
218 * Not used by external metadata. */
219 unsigned int size; /* Size in sectors of the PPL space */
220 sector_t sector; /* First sector of the PPL space */
221 } ppl;
222 };
223 enum flag_bits {
224 Faulty, /* device is known to have a fault */
225 In_sync, /* device is in_sync with rest of array */
226 Bitmap_sync, /* ..actually, not quite In_sync. Need a
227 * bitmap-based recovery to get fully in sync.
228 * The bit is only meaningful before device
229 * has been passed to pers->hot_add_disk.
230 */
231 WriteMostly, /* Avoid reading if at all possible */
232 AutoDetected, /* added by auto-detect */
233 Blocked, /* An error occurred but has not yet
234 * been acknowledged by the metadata
235 * handler, so don't allow writes
236 * until it is cleared */
237 WriteErrorSeen, /* A write error has been seen on this
238 * device
239 */
240 FaultRecorded, /* Intermediate state for clearing
241 * Blocked. The Fault is/will-be
242 * recorded in the metadata, but that
243 * metadata hasn't been stored safely
244 * on disk yet.
245 */
246 BlockedBadBlocks, /* A writer is blocked because they
247 * found an unacknowledged bad-block.
248 * This can safely be cleared at any
249 * time, and the writer will re-check.
250 * It may be set at any time, and at
251 * worst the writer will timeout and
252 * re-check. So setting it as
253 * accurately as possible is good, but
254 * not absolutely critical.
255 */
256 WantReplacement, /* This device is a candidate to be
257 * hot-replaced, either because it has
258 * reported some faults, or because
259 * of explicit request.
260 */
261 Replacement, /* This device is a replacement for
262 * a want_replacement device with same
263 * raid_disk number.
264 */
265 Candidate, /* For clustered environments only:
266 * This device is seen locally but not
267 * by the whole cluster
268 */
269 Journal, /* This device is used as journal for
270 * raid-5/6.
271 * Usually, this device should be faster
272 * than other devices in the array
273 */
274 ClusterRemove,
275 ExternalBbl, /* External metadata provides bad
276 * block management for a disk
277 */
278 FailFast, /* Minimal retries should be attempted on
279 * this device, so use REQ_FAILFAST_DEV.
280 * Also don't try to repair failed reads.
281 * It is expects that no bad block log
282 * is present.
283 */
284 LastDev, /* Seems to be the last working dev as
285 * it didn't fail, so don't use FailFast
286 * any more for metadata
287 */
288 CollisionCheck, /*
289 * check if there is collision between raid1
290 * serial bios.
291 */
292 Nonrot, /* non-rotational device (SSD) */
293 };
294
is_badblock(struct md_rdev * rdev,sector_t s,sector_t sectors,sector_t * first_bad,sector_t * bad_sectors)295 static inline int is_badblock(struct md_rdev *rdev, sector_t s, sector_t sectors,
296 sector_t *first_bad, sector_t *bad_sectors)
297 {
298 if (unlikely(rdev->badblocks.count)) {
299 int rv = badblocks_check(&rdev->badblocks, rdev->data_offset + s,
300 sectors,
301 first_bad, bad_sectors);
302 if (rv)
303 *first_bad -= rdev->data_offset;
304 return rv;
305 }
306 return 0;
307 }
308
rdev_has_badblock(struct md_rdev * rdev,sector_t s,int sectors)309 static inline int rdev_has_badblock(struct md_rdev *rdev, sector_t s,
310 int sectors)
311 {
312 sector_t first_bad;
313 sector_t bad_sectors;
314
315 return is_badblock(rdev, s, sectors, &first_bad, &bad_sectors);
316 }
317
318 extern bool rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
319 int is_new);
320 extern void rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
321 int is_new);
322 struct md_cluster_info;
323 struct md_cluster_operations;
324
325 /**
326 * enum mddev_flags - md device flags.
327 * @MD_ARRAY_FIRST_USE: First use of array, needs initialization.
328 * @MD_CLOSING: If set, we are closing the array, do not open it then.
329 * @MD_JOURNAL_CLEAN: A raid with journal is already clean.
330 * @MD_HAS_JOURNAL: The raid array has journal feature set.
331 * @MD_CLUSTER_RESYNC_LOCKED: cluster raid only, which means node, already took
332 * resync lock, need to release the lock.
333 * @MD_FAILFAST_SUPPORTED: Using MD_FAILFAST on metadata writes is supported as
334 * calls to md_error() will never cause the array to
335 * become failed.
336 * @MD_HAS_PPL: The raid array has PPL feature set.
337 * @MD_HAS_MULTIPLE_PPLS: The raid array has multiple PPLs feature set.
338 * @MD_NOT_READY: do_md_run() is active, so 'array_state', ust not report that
339 * array is ready yet.
340 * @MD_BROKEN: This is used to stop writes and mark array as failed.
341 * @MD_DELETED: This device is being deleted
342 *
343 * change UNSUPPORTED_MDDEV_FLAGS for each array type if new flag is added
344 */
345 enum mddev_flags {
346 MD_ARRAY_FIRST_USE,
347 MD_CLOSING,
348 MD_JOURNAL_CLEAN,
349 MD_HAS_JOURNAL,
350 MD_CLUSTER_RESYNC_LOCKED,
351 MD_FAILFAST_SUPPORTED,
352 MD_HAS_PPL,
353 MD_HAS_MULTIPLE_PPLS,
354 MD_NOT_READY,
355 MD_BROKEN,
356 MD_DELETED,
357 };
358
359 enum mddev_sb_flags {
360 MD_SB_CHANGE_DEVS, /* Some device status has changed */
361 MD_SB_CHANGE_CLEAN, /* transition to or from 'clean' */
362 MD_SB_CHANGE_PENDING, /* switch from 'clean' to 'active' in progress */
363 MD_SB_NEED_REWRITE, /* metadata write needs to be repeated */
364 };
365
366 #define NR_SERIAL_INFOS 8
367 /* record current range of serialize IOs */
368 struct serial_info {
369 struct rb_node node;
370 sector_t start; /* start sector of rb node */
371 sector_t last; /* end sector of rb node */
372 sector_t _subtree_last; /* highest sector in subtree of rb node */
373 };
374
375 /*
376 * mddev->curr_resync stores the current sector of the resync but
377 * also has some overloaded values.
378 */
379 enum {
380 /* No resync in progress */
381 MD_RESYNC_NONE = 0,
382 /* Yielded to allow another conflicting resync to commence */
383 MD_RESYNC_YIELDED = 1,
384 /* Delayed to check that there is no conflict with another sync */
385 MD_RESYNC_DELAYED = 2,
386 /* Any value greater than or equal to this is in an active resync */
387 MD_RESYNC_ACTIVE = 3,
388 };
389
390 struct mddev {
391 void *private;
392 struct md_personality *pers;
393 dev_t unit;
394 int md_minor;
395 struct list_head disks;
396 unsigned long flags;
397 unsigned long sb_flags;
398
399 int suspended;
400 struct mutex suspend_mutex;
401 struct percpu_ref active_io;
402 int ro;
403 int sysfs_active; /* set when sysfs deletes
404 * are happening, so run/
405 * takeover/stop are not safe
406 */
407 struct gendisk *gendisk; /* mdraid gendisk */
408 struct gendisk *dm_gendisk; /* dm-raid gendisk */
409
410 struct kobject kobj;
411 int hold_active;
412 #define UNTIL_IOCTL 1
413 #define UNTIL_STOP 2
414
415 /* Superblock information */
416 int major_version,
417 minor_version,
418 patch_version;
419 int persistent;
420 int external; /* metadata is
421 * managed externally */
422 char metadata_type[17]; /* externally set*/
423 int chunk_sectors;
424 time64_t ctime, utime;
425 int level, layout;
426 char clevel[16];
427 int raid_disks;
428 int max_disks;
429 sector_t dev_sectors; /* used size of
430 * component devices */
431 sector_t array_sectors; /* exported array size */
432 int external_size; /* size managed
433 * externally */
434 __u64 events;
435 /* If the last 'event' was simply a clean->dirty transition, and
436 * we didn't write it to the spares, then it is safe and simple
437 * to just decrement the event count on a dirty->clean transition.
438 * So we record that possibility here.
439 */
440 int can_decrease_events;
441
442 char uuid[16];
443
444 /* If the array is being reshaped, we need to record the
445 * new shape and an indication of where we are up to.
446 * This is written to the superblock.
447 * If reshape_position is MaxSector, then no reshape is happening (yet).
448 */
449 sector_t reshape_position;
450 int delta_disks, new_level, new_layout;
451 int new_chunk_sectors;
452 int reshape_backwards;
453
454 struct md_thread __rcu *thread; /* management thread */
455 struct md_thread __rcu *sync_thread; /* doing resync or reconstruct */
456
457 /*
458 * Set when a sync operation is started. It holds this value even
459 * when the sync thread is "frozen" (interrupted) or "idle" (stopped
460 * or finished). It is overwritten when a new sync operation is begun.
461 */
462 enum sync_action last_sync_action;
463 sector_t curr_resync; /* last block scheduled */
464 /* As resync requests can complete out of order, we cannot easily track
465 * how much resync has been completed. So we occasionally pause until
466 * everything completes, then set curr_resync_completed to curr_resync.
467 * As such it may be well behind the real resync mark, but it is a value
468 * we are certain of.
469 */
470 sector_t curr_resync_completed;
471 unsigned long resync_mark; /* a recent timestamp */
472 sector_t resync_mark_cnt;/* blocks written at resync_mark */
473 sector_t curr_mark_cnt; /* blocks scheduled now */
474
475 sector_t resync_max_sectors; /* may be set by personality */
476
477 atomic64_t resync_mismatches; /* count of sectors where
478 * parity/replica mismatch found
479 */
480
481 /* allow user-space to request suspension of IO to regions of the array */
482 sector_t suspend_lo;
483 sector_t suspend_hi;
484 /* if zero, use the system-wide default */
485 int sync_speed_min;
486 int sync_speed_max;
487 int sync_io_depth;
488
489 /* resync even though the same disks are shared among md-devices */
490 int parallel_resync;
491
492 int ok_start_degraded;
493
494 unsigned long recovery;
495 /* If a RAID personality determines that recovery (of a particular
496 * device) will fail due to a read error on the source device, it
497 * takes a copy of this number and does not attempt recovery again
498 * until this number changes.
499 */
500 int recovery_disabled;
501
502 int in_sync; /* know to not need resync */
503 /* 'open_mutex' avoids races between 'md_open' and 'do_md_stop', so
504 * that we are never stopping an array while it is open.
505 * 'reconfig_mutex' protects all other reconfiguration.
506 * These locks are separate due to conflicting interactions
507 * with disk->open_mutex.
508 * Lock ordering is:
509 * reconfig_mutex -> disk->open_mutex
510 * disk->open_mutex -> open_mutex: e.g. __blkdev_get -> md_open
511 */
512 struct mutex open_mutex;
513 struct mutex reconfig_mutex;
514 atomic_t active; /* general refcount */
515 atomic_t openers; /* number of active opens */
516
517 int changed; /* True if we might need to
518 * reread partition info */
519 int degraded; /* whether md should consider
520 * adding a spare
521 */
522
523 unsigned long normal_io_events; /* IO event timestamp */
524 atomic_t recovery_active; /* blocks scheduled, but not written */
525 wait_queue_head_t recovery_wait;
526 sector_t resync_offset;
527 sector_t resync_min; /* user requested sync
528 * starts here */
529 sector_t resync_max; /* resync should pause
530 * when it gets here */
531
532 struct kernfs_node *sysfs_state; /* handle for 'array_state'
533 * file in sysfs.
534 */
535 struct kernfs_node *sysfs_action; /* handle for 'sync_action' */
536 struct kernfs_node *sysfs_completed; /*handle for 'sync_completed' */
537 struct kernfs_node *sysfs_degraded; /*handle for 'degraded' */
538 struct kernfs_node *sysfs_level; /*handle for 'level' */
539
540 /* used for delayed sysfs removal */
541 struct work_struct del_work;
542 /* used for register new sync thread */
543 struct work_struct sync_work;
544
545 /* "lock" protects:
546 * flush_bio transition from NULL to !NULL
547 * rdev superblocks, events
548 * clearing MD_CHANGE_*
549 * in_sync - and related safemode and MD_CHANGE changes
550 * pers (also protected by reconfig_mutex and pending IO).
551 * clearing ->bitmap
552 * clearing ->bitmap_info.file
553 * changing ->resync_{min,max}
554 * setting MD_RECOVERY_RUNNING (which interacts with resync_{min,max})
555 */
556 spinlock_t lock;
557 wait_queue_head_t sb_wait; /* for waiting on superblock updates */
558 atomic_t pending_writes; /* number of active superblock writes */
559
560 unsigned int safemode; /* if set, update "clean" superblock
561 * when no writes pending.
562 */
563 unsigned int safemode_delay;
564 struct timer_list safemode_timer;
565 struct percpu_ref writes_pending;
566 int sync_checkers; /* # of threads checking writes_pending */
567
568 void *bitmap; /* the bitmap for the device */
569 struct bitmap_operations *bitmap_ops;
570 struct {
571 struct file *file; /* the bitmap file */
572 loff_t offset; /* offset from superblock of
573 * start of bitmap. May be
574 * negative, but not '0'
575 * For external metadata, offset
576 * from start of device.
577 */
578 unsigned long space; /* space available at this offset */
579 loff_t default_offset; /* this is the offset to use when
580 * hot-adding a bitmap. It should
581 * eventually be settable by sysfs.
582 */
583 unsigned long default_space; /* space available at
584 * default offset */
585 struct mutex mutex;
586 unsigned long chunksize;
587 unsigned long daemon_sleep; /* how many jiffies between updates? */
588 unsigned long max_write_behind; /* write-behind mode */
589 int external;
590 int nodes; /* Maximum number of nodes in the cluster */
591 char cluster_name[64]; /* Name of the cluster */
592 } bitmap_info;
593
594 atomic_t max_corr_read_errors; /* max read retries */
595 struct list_head all_mddevs;
596
597 const struct attribute_group *to_remove;
598
599 struct bio_set bio_set;
600 struct bio_set sync_set; /* for sync operations like
601 * metadata and bitmap writes
602 */
603 struct bio_set io_clone_set;
604
605 struct work_struct event_work; /* used by dm to report failure event */
606 mempool_t *serial_info_pool;
607 void (*sync_super)(struct mddev *mddev, struct md_rdev *rdev);
608 struct md_cluster_info *cluster_info;
609 struct md_cluster_operations *cluster_ops;
610 unsigned int good_device_nr; /* good device num within cluster raid */
611 unsigned int noio_flag; /* for memalloc scope API */
612
613 /*
614 * Temporarily store rdev that will be finally removed when
615 * reconfig_mutex is unlocked, protected by reconfig_mutex.
616 */
617 struct list_head deleting;
618
619 /* The sequence number for sync thread */
620 atomic_t sync_seq;
621
622 bool has_superblocks:1;
623 bool fail_last_dev:1;
624 bool serialize_policy:1;
625 };
626
627 enum recovery_flags {
628 /* flags for sync thread running status */
629
630 /*
631 * set when one of sync action is set and new sync thread need to be
632 * registered, or just add/remove spares from conf.
633 */
634 MD_RECOVERY_NEEDED,
635 /* sync thread is running, or about to be started */
636 MD_RECOVERY_RUNNING,
637 /* sync thread needs to be aborted for some reason */
638 MD_RECOVERY_INTR,
639 /* sync thread is done and is waiting to be unregistered */
640 MD_RECOVERY_DONE,
641 /* running sync thread must abort immediately, and not restart */
642 MD_RECOVERY_FROZEN,
643 /* waiting for pers->start() to finish */
644 MD_RECOVERY_WAIT,
645 /* interrupted because io-error */
646 MD_RECOVERY_ERROR,
647
648 /* flags determines sync action, see details in enum sync_action */
649
650 /* if just this flag is set, action is resync. */
651 MD_RECOVERY_SYNC,
652 /*
653 * paired with MD_RECOVERY_SYNC, if MD_RECOVERY_CHECK is not set,
654 * action is repair, means user requested resync.
655 */
656 MD_RECOVERY_REQUESTED,
657 /*
658 * paired with MD_RECOVERY_SYNC and MD_RECOVERY_REQUESTED, action is
659 * check.
660 */
661 MD_RECOVERY_CHECK,
662 /* recovery, or need to try it */
663 MD_RECOVERY_RECOVER,
664 /* reshape */
665 MD_RECOVERY_RESHAPE,
666 /* remote node is running resync thread */
667 MD_RESYNCING_REMOTE,
668 };
669
670 enum md_ro_state {
671 MD_RDWR,
672 MD_RDONLY,
673 MD_AUTO_READ,
674 MD_MAX_STATE
675 };
676
md_is_rdwr(struct mddev * mddev)677 static inline bool md_is_rdwr(struct mddev *mddev)
678 {
679 return (mddev->ro == MD_RDWR);
680 }
681
reshape_interrupted(struct mddev * mddev)682 static inline bool reshape_interrupted(struct mddev *mddev)
683 {
684 /* reshape never start */
685 if (mddev->reshape_position == MaxSector)
686 return false;
687
688 /* interrupted */
689 if (!test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
690 return true;
691
692 /* running reshape will be interrupted soon. */
693 if (test_bit(MD_RECOVERY_WAIT, &mddev->recovery) ||
694 test_bit(MD_RECOVERY_INTR, &mddev->recovery) ||
695 test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
696 return true;
697
698 return false;
699 }
700
mddev_lock(struct mddev * mddev)701 static inline int __must_check mddev_lock(struct mddev *mddev)
702 {
703 int ret;
704
705 ret = mutex_lock_interruptible(&mddev->reconfig_mutex);
706
707 /* MD_DELETED is set in do_md_stop with reconfig_mutex.
708 * So check it here.
709 */
710 if (!ret && test_bit(MD_DELETED, &mddev->flags)) {
711 ret = -ENODEV;
712 mutex_unlock(&mddev->reconfig_mutex);
713 }
714
715 return ret;
716 }
717
718 /* Sometimes we need to take the lock in a situation where
719 * failure due to interrupts is not acceptable.
720 * It doesn't need to check MD_DELETED here, the owner which
721 * holds the lock here can't be stopped. And all paths can't
722 * call this function after do_md_stop.
723 */
mddev_lock_nointr(struct mddev * mddev)724 static inline void mddev_lock_nointr(struct mddev *mddev)
725 {
726 mutex_lock(&mddev->reconfig_mutex);
727 }
728
mddev_trylock(struct mddev * mddev)729 static inline int mddev_trylock(struct mddev *mddev)
730 {
731 int ret;
732
733 ret = mutex_trylock(&mddev->reconfig_mutex);
734 if (!ret && test_bit(MD_DELETED, &mddev->flags)) {
735 ret = -ENODEV;
736 mutex_unlock(&mddev->reconfig_mutex);
737 }
738 return ret;
739 }
740 extern void mddev_unlock(struct mddev *mddev);
741
742 struct md_personality
743 {
744 struct md_submodule_head head;
745
746 bool __must_check (*make_request)(struct mddev *mddev, struct bio *bio);
747 /*
748 * start up works that do NOT require md_thread. tasks that
749 * requires md_thread should go into start()
750 */
751 int (*run)(struct mddev *mddev);
752 /* start up works that require md threads */
753 int (*start)(struct mddev *mddev);
754 void (*free)(struct mddev *mddev, void *priv);
755 void (*status)(struct seq_file *seq, struct mddev *mddev);
756 /* error_handler must set ->faulty and clear ->in_sync
757 * if appropriate, and should abort recovery if needed
758 */
759 void (*error_handler)(struct mddev *mddev, struct md_rdev *rdev);
760 int (*hot_add_disk) (struct mddev *mddev, struct md_rdev *rdev);
761 int (*hot_remove_disk) (struct mddev *mddev, struct md_rdev *rdev);
762 int (*spare_active) (struct mddev *mddev);
763 sector_t (*sync_request)(struct mddev *mddev, sector_t sector_nr,
764 sector_t max_sector, int *skipped);
765 int (*resize) (struct mddev *mddev, sector_t sectors);
766 sector_t (*size) (struct mddev *mddev, sector_t sectors, int raid_disks);
767 int (*check_reshape) (struct mddev *mddev);
768 int (*start_reshape) (struct mddev *mddev);
769 void (*finish_reshape) (struct mddev *mddev);
770 void (*update_reshape_pos) (struct mddev *mddev);
771 void (*prepare_suspend) (struct mddev *mddev);
772 /* quiesce suspends or resumes internal processing.
773 * 1 - stop new actions and wait for action io to complete
774 * 0 - return to normal behaviour
775 */
776 void (*quiesce) (struct mddev *mddev, int quiesce);
777 /* takeover is used to transition an array from one
778 * personality to another. The new personality must be able
779 * to handle the data in the current layout.
780 * e.g. 2drive raid1 -> 2drive raid5
781 * ndrive raid5 -> degraded n+1drive raid6 with special layout
782 * If the takeover succeeds, a new 'private' structure is returned.
783 * This needs to be installed and then ->run used to activate the
784 * array.
785 */
786 void *(*takeover) (struct mddev *mddev);
787 /* Changes the consistency policy of an active array. */
788 int (*change_consistency_policy)(struct mddev *mddev, const char *buf);
789 /* convert io ranges from array to bitmap */
790 void (*bitmap_sector)(struct mddev *mddev, sector_t *offset,
791 unsigned long *sectors);
792 };
793
794 struct md_sysfs_entry {
795 struct attribute attr;
796 ssize_t (*show)(struct mddev *, char *);
797 ssize_t (*store)(struct mddev *, const char *, size_t);
798 };
799 extern const struct attribute_group md_bitmap_group;
800
sysfs_get_dirent_safe(struct kernfs_node * sd,char * name)801 static inline struct kernfs_node *sysfs_get_dirent_safe(struct kernfs_node *sd, char *name)
802 {
803 if (sd)
804 return sysfs_get_dirent(sd, name);
805 return sd;
806 }
sysfs_notify_dirent_safe(struct kernfs_node * sd)807 static inline void sysfs_notify_dirent_safe(struct kernfs_node *sd)
808 {
809 if (sd)
810 sysfs_notify_dirent(sd);
811 }
812
mdname(struct mddev * mddev)813 static inline char * mdname (struct mddev * mddev)
814 {
815 return mddev->gendisk ? mddev->gendisk->disk_name : "mdX";
816 }
817
sysfs_link_rdev(struct mddev * mddev,struct md_rdev * rdev)818 static inline int sysfs_link_rdev(struct mddev *mddev, struct md_rdev *rdev)
819 {
820 char nm[20];
821 if (!test_bit(Replacement, &rdev->flags) &&
822 !test_bit(Journal, &rdev->flags) &&
823 mddev->kobj.sd) {
824 sprintf(nm, "rd%d", rdev->raid_disk);
825 return sysfs_create_link(&mddev->kobj, &rdev->kobj, nm);
826 } else
827 return 0;
828 }
829
sysfs_unlink_rdev(struct mddev * mddev,struct md_rdev * rdev)830 static inline void sysfs_unlink_rdev(struct mddev *mddev, struct md_rdev *rdev)
831 {
832 char nm[20];
833 if (!test_bit(Replacement, &rdev->flags) &&
834 !test_bit(Journal, &rdev->flags) &&
835 mddev->kobj.sd) {
836 sprintf(nm, "rd%d", rdev->raid_disk);
837 sysfs_remove_link(&mddev->kobj, nm);
838 }
839 }
840
841 /*
842 * iterates through some rdev ringlist. It's safe to remove the
843 * current 'rdev'. Dont touch 'tmp' though.
844 */
845 #define rdev_for_each_list(rdev, tmp, head) \
846 list_for_each_entry_safe(rdev, tmp, head, same_set)
847
848 /*
849 * iterates through the 'same array disks' ringlist
850 */
851 #define rdev_for_each(rdev, mddev) \
852 list_for_each_entry(rdev, &((mddev)->disks), same_set)
853
854 #define rdev_for_each_safe(rdev, tmp, mddev) \
855 list_for_each_entry_safe(rdev, tmp, &((mddev)->disks), same_set)
856
857 #define rdev_for_each_rcu(rdev, mddev) \
858 list_for_each_entry_rcu(rdev, &((mddev)->disks), same_set)
859
860 struct md_thread {
861 void (*run) (struct md_thread *thread);
862 struct mddev *mddev;
863 wait_queue_head_t wqueue;
864 unsigned long flags;
865 struct task_struct *tsk;
866 unsigned long timeout;
867 void *private;
868 };
869
870 struct md_io_clone {
871 struct mddev *mddev;
872 struct bio *orig_bio;
873 unsigned long start_time;
874 sector_t offset;
875 unsigned long sectors;
876 struct bio bio_clone;
877 };
878
879 #define THREAD_WAKEUP 0
880
safe_put_page(struct page * p)881 static inline void safe_put_page(struct page *p)
882 {
883 if (p) put_page(p);
884 }
885
886 int register_md_submodule(struct md_submodule_head *msh);
887 void unregister_md_submodule(struct md_submodule_head *msh);
888
889 extern struct md_thread *md_register_thread(
890 void (*run)(struct md_thread *thread),
891 struct mddev *mddev,
892 const char *name);
893 extern void md_unregister_thread(struct mddev *mddev, struct md_thread __rcu **threadp);
894 extern void md_wakeup_thread(struct md_thread __rcu *thread);
895 extern void md_check_recovery(struct mddev *mddev);
896 extern void md_reap_sync_thread(struct mddev *mddev);
897 extern enum sync_action md_sync_action(struct mddev *mddev);
898 extern enum sync_action md_sync_action_by_name(const char *page);
899 extern const char *md_sync_action_name(enum sync_action action);
900 extern void md_write_start(struct mddev *mddev, struct bio *bi);
901 extern void md_write_inc(struct mddev *mddev, struct bio *bi);
902 extern void md_write_end(struct mddev *mddev);
903 extern void md_done_sync(struct mddev *mddev, int blocks, int ok);
904 extern void md_error(struct mddev *mddev, struct md_rdev *rdev);
905 extern void md_finish_reshape(struct mddev *mddev);
906 void md_submit_discard_bio(struct mddev *mddev, struct md_rdev *rdev,
907 struct bio *bio, sector_t start, sector_t size);
908 void md_account_bio(struct mddev *mddev, struct bio **bio);
909 void md_free_cloned_bio(struct bio *bio);
910
911 extern bool __must_check md_flush_request(struct mddev *mddev, struct bio *bio);
912 extern void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
913 sector_t sector, int size, struct page *page);
914 extern int md_super_wait(struct mddev *mddev);
915 extern int sync_page_io(struct md_rdev *rdev, sector_t sector, int size,
916 struct page *page, blk_opf_t opf, bool metadata_op);
917 extern void md_do_sync(struct md_thread *thread);
918 extern void md_new_event(void);
919 extern void md_allow_write(struct mddev *mddev);
920 extern void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev);
921 extern void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors);
922 extern int md_check_no_bitmap(struct mddev *mddev);
923 extern int md_integrity_register(struct mddev *mddev);
924 extern int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale);
925
926 extern int mddev_init(struct mddev *mddev);
927 extern void mddev_destroy(struct mddev *mddev);
928 void md_init_stacking_limits(struct queue_limits *lim);
929 struct mddev *md_alloc(dev_t dev, char *name);
930 void mddev_put(struct mddev *mddev);
931 extern int md_run(struct mddev *mddev);
932 extern int md_start(struct mddev *mddev);
933 extern void md_stop(struct mddev *mddev);
934 extern void md_stop_writes(struct mddev *mddev);
935 extern int md_rdev_init(struct md_rdev *rdev);
936 extern void md_rdev_clear(struct md_rdev *rdev);
937
938 extern bool md_handle_request(struct mddev *mddev, struct bio *bio);
939 extern int mddev_suspend(struct mddev *mddev, bool interruptible);
940 extern void mddev_resume(struct mddev *mddev);
941 extern void md_idle_sync_thread(struct mddev *mddev);
942 extern void md_frozen_sync_thread(struct mddev *mddev);
943 extern void md_unfrozen_sync_thread(struct mddev *mddev);
944
945 extern void md_update_sb(struct mddev *mddev, int force);
946 extern void mddev_create_serial_pool(struct mddev *mddev, struct md_rdev *rdev);
947 extern void mddev_destroy_serial_pool(struct mddev *mddev,
948 struct md_rdev *rdev);
949 struct md_rdev *md_find_rdev_nr_rcu(struct mddev *mddev, int nr);
950 struct md_rdev *md_find_rdev_rcu(struct mddev *mddev, dev_t dev);
951
is_rdev_broken(struct md_rdev * rdev)952 static inline bool is_rdev_broken(struct md_rdev *rdev)
953 {
954 return !disk_live(rdev->bdev->bd_disk);
955 }
956
rdev_dec_pending(struct md_rdev * rdev,struct mddev * mddev)957 static inline void rdev_dec_pending(struct md_rdev *rdev, struct mddev *mddev)
958 {
959 int faulty = test_bit(Faulty, &rdev->flags);
960 if (atomic_dec_and_test(&rdev->nr_pending) && faulty) {
961 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
962 md_wakeup_thread(mddev->thread);
963 }
964 }
965
mddev_is_clustered(struct mddev * mddev)966 static inline int mddev_is_clustered(struct mddev *mddev)
967 {
968 return mddev->cluster_info && mddev->bitmap_info.nodes > 1;
969 }
970
971 /* clear unsupported mddev_flags */
mddev_clear_unsupported_flags(struct mddev * mddev,unsigned long unsupported_flags)972 static inline void mddev_clear_unsupported_flags(struct mddev *mddev,
973 unsigned long unsupported_flags)
974 {
975 mddev->flags &= ~unsupported_flags;
976 }
977
mddev_check_write_zeroes(struct mddev * mddev,struct bio * bio)978 static inline void mddev_check_write_zeroes(struct mddev *mddev, struct bio *bio)
979 {
980 if (bio_op(bio) == REQ_OP_WRITE_ZEROES &&
981 !bio->bi_bdev->bd_disk->queue->limits.max_write_zeroes_sectors)
982 mddev->gendisk->queue->limits.max_write_zeroes_sectors = 0;
983 }
984
mddev_suspend_and_lock(struct mddev * mddev)985 static inline int mddev_suspend_and_lock(struct mddev *mddev)
986 {
987 int ret;
988
989 ret = mddev_suspend(mddev, true);
990 if (ret)
991 return ret;
992
993 ret = mddev_lock(mddev);
994 if (ret)
995 mddev_resume(mddev);
996
997 return ret;
998 }
999
mddev_suspend_and_lock_nointr(struct mddev * mddev)1000 static inline void mddev_suspend_and_lock_nointr(struct mddev *mddev)
1001 {
1002 mddev_suspend(mddev, false);
1003 mutex_lock(&mddev->reconfig_mutex);
1004 }
1005
mddev_unlock_and_resume(struct mddev * mddev)1006 static inline void mddev_unlock_and_resume(struct mddev *mddev)
1007 {
1008 mddev_unlock(mddev);
1009 mddev_resume(mddev);
1010 }
1011
1012 struct mdu_array_info_s;
1013 struct mdu_disk_info_s;
1014
1015 extern int mdp_major;
1016 extern struct workqueue_struct *md_bitmap_wq;
1017 void md_autostart_arrays(int part);
1018 int md_set_array_info(struct mddev *mddev, struct mdu_array_info_s *info);
1019 int md_add_new_disk(struct mddev *mddev, struct mdu_disk_info_s *info);
1020 int do_md_run(struct mddev *mddev);
1021 #define MDDEV_STACK_INTEGRITY (1u << 0)
1022 int mddev_stack_rdev_limits(struct mddev *mddev, struct queue_limits *lim,
1023 unsigned int flags);
1024 int mddev_stack_new_rdev(struct mddev *mddev, struct md_rdev *rdev);
1025 void mddev_update_io_opt(struct mddev *mddev, unsigned int nr_stripes);
1026
1027 extern const struct block_device_operations md_fops;
1028
1029 /*
1030 * MD devices can be used undeneath by DM, in which case ->gendisk is NULL.
1031 */
mddev_is_dm(struct mddev * mddev)1032 static inline bool mddev_is_dm(struct mddev *mddev)
1033 {
1034 return !mddev->gendisk;
1035 }
1036
mddev_trace_remap(struct mddev * mddev,struct bio * bio,sector_t sector)1037 static inline void mddev_trace_remap(struct mddev *mddev, struct bio *bio,
1038 sector_t sector)
1039 {
1040 if (!mddev_is_dm(mddev))
1041 trace_block_bio_remap(bio, disk_devt(mddev->gendisk), sector);
1042 }
1043
rdev_blocked(struct md_rdev * rdev)1044 static inline bool rdev_blocked(struct md_rdev *rdev)
1045 {
1046 /*
1047 * Blocked will be set by error handler and cleared by daemon after
1048 * updating superblock, meanwhile write IO should be blocked to prevent
1049 * reading old data after power failure.
1050 */
1051 if (test_bit(Blocked, &rdev->flags))
1052 return true;
1053
1054 /*
1055 * Faulty device should not be accessed anymore, there is no need to
1056 * wait for bad block to be acknowledged.
1057 */
1058 if (test_bit(Faulty, &rdev->flags))
1059 return false;
1060
1061 /* rdev is blocked by badblocks. */
1062 if (test_bit(BlockedBadBlocks, &rdev->flags))
1063 return true;
1064
1065 return false;
1066 }
1067
1068 #define mddev_add_trace_msg(mddev, fmt, args...) \
1069 do { \
1070 if (!mddev_is_dm(mddev)) \
1071 blk_add_trace_msg((mddev)->gendisk->queue, fmt, ##args); \
1072 } while (0)
1073
1074 #endif /* _MD_MD_H */
1075