1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 md.h : kernel internal structure of the Linux MD driver
4 Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman
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>
17 #include <linux/mutex.h>
18 #include <linux/timer.h>
19 #include <linux/wait.h>
20 #include <linux/workqueue.h>
21 #include "md-cluster.h"
23 #define MaxSector (~(sector_t)0)
26 * These flags should really be called "NO_RETRY" rather than
27 * "FAILFAST" because they don't make any promise about time lapse,
28 * only about the number of retries, which will be zero.
29 * REQ_FAILFAST_DRIVER is not included because
30 * Commit: 4a27446f3e39 ("[SCSI] modify scsi to handle new fail fast flags.")
31 * seems to suggest that the errors it avoids retrying should usually
34 #define MD_FAILFAST (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT)
37 * The struct embedded in rdev is used to serialize IO.
39 struct serial_in_rdev {
40 struct rb_root_cached serial_rb;
41 spinlock_t serial_lock;
42 wait_queue_head_t serial_io_wait;
46 * MD's 'extended' device
49 struct list_head same_set; /* RAID devices within the same set */
51 sector_t sectors; /* Device size (in 512bytes sectors) */
52 struct mddev *mddev; /* RAID array if running */
53 int last_events; /* IO event timestamp */
56 * If meta_bdev is non-NULL, it means that a separate device is
57 * being used to store the metadata (superblock/bitmap) which
58 * would otherwise be contained on the same device as the data (bdev).
60 struct block_device *meta_bdev;
61 struct block_device *bdev; /* block device handle */
62 struct bdev_handle *bdev_handle; /* Handle from open for bdev */
64 struct page *sb_page, *bb_page;
67 sector_t data_offset; /* start of data in array */
68 sector_t new_data_offset;/* only relevant while reshaping */
69 sector_t sb_start; /* offset of the super block (in 512byte sectors) */
70 int sb_size; /* bytes in the superblock */
71 int preferred_minor; /* autorun support */
75 /* A device can be in one of three states based on two flags:
76 * Not working: faulty==1 in_sync==0
77 * Fully working: faulty==0 in_sync==1
80 * faulty==0 in_sync==0
82 * It can never have faulty==1, in_sync==1
83 * This reduces the burden of testing multiple flags in many cases
86 unsigned long flags; /* bit set of 'enum flag_bits' bits. */
87 wait_queue_head_t blocked_wait;
89 int desc_nr; /* descriptor index in the superblock */
90 int raid_disk; /* role of device in array */
91 int new_raid_disk; /* role that the device will have in
92 * the array after a level-change completes.
94 int saved_raid_disk; /* role that device used to have in the
95 * array and could again if we did a partial
96 * resync from the bitmap
99 sector_t recovery_offset;/* If this device has been partially
100 * recovered, this is where we were
103 sector_t journal_tail; /* If this device is a journal device,
104 * this is the journal tail (journal
105 * recovery start point)
109 atomic_t nr_pending; /* number of pending requests.
110 * only maintained for arrays that
111 * support hot removal
113 atomic_t read_errors; /* number of consecutive read errors that
114 * we have tried to ignore.
116 time64_t last_read_error; /* monotonic time since our
119 atomic_t corrected_errors; /* number of corrected read errors,
120 * for reporting to userspace and storing
124 struct serial_in_rdev *serial; /* used for raid1 io serialization */
126 struct kernfs_node *sysfs_state; /* handle for 'state'
128 /* handle for 'unacknowledged_bad_blocks' sysfs dentry */
129 struct kernfs_node *sysfs_unack_badblocks;
130 /* handle for 'bad_blocks' sysfs dentry */
131 struct kernfs_node *sysfs_badblocks;
132 struct badblocks badblocks;
135 short offset; /* Offset from superblock to start of PPL.
136 * Not used by external metadata. */
137 unsigned int size; /* Size in sectors of the PPL space */
138 sector_t sector; /* First sector of the PPL space */
142 Faulty, /* device is known to have a fault */
143 In_sync, /* device is in_sync with rest of array */
144 Bitmap_sync, /* ..actually, not quite In_sync. Need a
145 * bitmap-based recovery to get fully in sync.
146 * The bit is only meaningful before device
147 * has been passed to pers->hot_add_disk.
149 WriteMostly, /* Avoid reading if at all possible */
150 AutoDetected, /* added by auto-detect */
151 Blocked, /* An error occurred but has not yet
152 * been acknowledged by the metadata
153 * handler, so don't allow writes
154 * until it is cleared */
155 WriteErrorSeen, /* A write error has been seen on this
158 FaultRecorded, /* Intermediate state for clearing
159 * Blocked. The Fault is/will-be
160 * recorded in the metadata, but that
161 * metadata hasn't been stored safely
164 BlockedBadBlocks, /* A writer is blocked because they
165 * found an unacknowledged bad-block.
166 * This can safely be cleared at any
167 * time, and the writer will re-check.
168 * It may be set at any time, and at
169 * worst the writer will timeout and
170 * re-check. So setting it as
171 * accurately as possible is good, but
172 * not absolutely critical.
174 WantReplacement, /* This device is a candidate to be
175 * hot-replaced, either because it has
176 * reported some faults, or because
177 * of explicit request.
179 Replacement, /* This device is a replacement for
180 * a want_replacement device with same
183 Candidate, /* For clustered environments only:
184 * This device is seen locally but not
185 * by the whole cluster
187 Journal, /* This device is used as journal for
189 * Usually, this device should be faster
190 * than other devices in the array
193 RemoveSynchronized, /* synchronize_rcu() was called after
194 * this device was known to be faulty,
195 * so it is safe to remove without
196 * another synchronize_rcu() call.
198 ExternalBbl, /* External metadata provides bad
199 * block management for a disk
201 FailFast, /* Minimal retries should be attempted on
202 * this device, so use REQ_FAILFAST_DEV.
203 * Also don't try to repair failed reads.
204 * It is expects that no bad block log
207 LastDev, /* Seems to be the last working dev as
208 * it didn't fail, so don't use FailFast
209 * any more for metadata
212 * check if there is collision between raid1
217 static inline int is_badblock(struct md_rdev *rdev, sector_t s, int sectors,
218 sector_t *first_bad, int *bad_sectors)
220 if (unlikely(rdev->badblocks.count)) {
221 int rv = badblocks_check(&rdev->badblocks, rdev->data_offset + s,
223 first_bad, bad_sectors);
225 *first_bad -= rdev->data_offset;
230 extern int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
232 extern int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
234 struct md_cluster_info;
237 * enum mddev_flags - md device flags.
238 * @MD_ARRAY_FIRST_USE: First use of array, needs initialization.
239 * @MD_CLOSING: If set, we are closing the array, do not open it then.
240 * @MD_JOURNAL_CLEAN: A raid with journal is already clean.
241 * @MD_HAS_JOURNAL: The raid array has journal feature set.
242 * @MD_CLUSTER_RESYNC_LOCKED: cluster raid only, which means node, already took
243 * resync lock, need to release the lock.
244 * @MD_FAILFAST_SUPPORTED: Using MD_FAILFAST on metadata writes is supported as
245 * calls to md_error() will never cause the array to
247 * @MD_HAS_PPL: The raid array has PPL feature set.
248 * @MD_HAS_MULTIPLE_PPLS: The raid array has multiple PPLs feature set.
249 * @MD_NOT_READY: do_md_run() is active, so 'array_state', ust not report that
250 * array is ready yet.
251 * @MD_BROKEN: This is used to stop writes and mark array as failed.
252 * @MD_DELETED: This device is being deleted
254 * change UNSUPPORTED_MDDEV_FLAGS for each array type if new flag is added
261 MD_CLUSTER_RESYNC_LOCKED,
262 MD_FAILFAST_SUPPORTED,
264 MD_HAS_MULTIPLE_PPLS,
270 enum mddev_sb_flags {
271 MD_SB_CHANGE_DEVS, /* Some device status has changed */
272 MD_SB_CHANGE_CLEAN, /* transition to or from 'clean' */
273 MD_SB_CHANGE_PENDING, /* switch from 'clean' to 'active' in progress */
274 MD_SB_NEED_REWRITE, /* metadata write needs to be repeated */
277 #define NR_SERIAL_INFOS 8
278 /* record current range of serialize IOs */
281 sector_t start; /* start sector of rb node */
282 sector_t last; /* end sector of rb node */
283 sector_t _subtree_last; /* highest sector in subtree of rb node */
287 * mddev->curr_resync stores the current sector of the resync but
288 * also has some overloaded values.
291 /* No resync in progress */
293 /* Yielded to allow another conflicting resync to commence */
294 MD_RESYNC_YIELDED = 1,
295 /* Delayed to check that there is no conflict with another sync */
296 MD_RESYNC_DELAYED = 2,
297 /* Any value greater than or equal to this is in an active resync */
298 MD_RESYNC_ACTIVE = 3,
303 struct md_personality *pers;
306 struct list_head disks;
308 unsigned long sb_flags;
311 struct mutex suspend_mutex;
312 struct percpu_ref active_io;
314 int sysfs_active; /* set when sysfs deletes
315 * are happening, so run/
316 * takeover/stop are not safe
318 struct gendisk *gendisk;
322 #define UNTIL_IOCTL 1
325 /* Superblock information */
330 int external; /* metadata is
331 * managed externally */
332 char metadata_type[17]; /* externally set*/
334 time64_t ctime, utime;
339 sector_t dev_sectors; /* used size of
340 * component devices */
341 sector_t array_sectors; /* exported array size */
342 int external_size; /* size managed
345 /* If the last 'event' was simply a clean->dirty transition, and
346 * we didn't write it to the spares, then it is safe and simple
347 * to just decrement the event count on a dirty->clean transition.
348 * So we record that possibility here.
350 int can_decrease_events;
354 /* If the array is being reshaped, we need to record the
355 * new shape and an indication of where we are up to.
356 * This is written to the superblock.
357 * If reshape_position is MaxSector, then no reshape is happening (yet).
359 sector_t reshape_position;
360 int delta_disks, new_level, new_layout;
361 int new_chunk_sectors;
362 int reshape_backwards;
364 struct md_thread __rcu *thread; /* management thread */
365 struct md_thread __rcu *sync_thread; /* doing resync or reconstruct */
367 /* 'last_sync_action' is initialized to "none". It is set when a
368 * sync operation (i.e "data-check", "requested-resync", "resync",
369 * "recovery", or "reshape") is started. It holds this value even
370 * when the sync thread is "frozen" (interrupted) or "idle" (stopped
371 * or finished). It is overwritten when a new sync operation is begun.
373 char *last_sync_action;
374 sector_t curr_resync; /* last block scheduled */
375 /* As resync requests can complete out of order, we cannot easily track
376 * how much resync has been completed. So we occasionally pause until
377 * everything completes, then set curr_resync_completed to curr_resync.
378 * As such it may be well behind the real resync mark, but it is a value
381 sector_t curr_resync_completed;
382 unsigned long resync_mark; /* a recent timestamp */
383 sector_t resync_mark_cnt;/* blocks written at resync_mark */
384 sector_t curr_mark_cnt; /* blocks scheduled now */
386 sector_t resync_max_sectors; /* may be set by personality */
388 atomic64_t resync_mismatches; /* count of sectors where
389 * parity/replica mismatch found
392 /* allow user-space to request suspension of IO to regions of the array */
395 /* if zero, use the system-wide default */
399 /* resync even though the same disks are shared among md-devices */
402 int ok_start_degraded;
404 unsigned long recovery;
405 /* If a RAID personality determines that recovery (of a particular
406 * device) will fail due to a read error on the source device, it
407 * takes a copy of this number and does not attempt recovery again
408 * until this number changes.
410 int recovery_disabled;
412 int in_sync; /* know to not need resync */
413 /* 'open_mutex' avoids races between 'md_open' and 'do_md_stop', so
414 * that we are never stopping an array while it is open.
415 * 'reconfig_mutex' protects all other reconfiguration.
416 * These locks are separate due to conflicting interactions
417 * with disk->open_mutex.
419 * reconfig_mutex -> disk->open_mutex
420 * disk->open_mutex -> open_mutex: e.g. __blkdev_get -> md_open
422 struct mutex open_mutex;
423 struct mutex reconfig_mutex;
424 atomic_t active; /* general refcount */
425 atomic_t openers; /* number of active opens */
427 int changed; /* True if we might need to
428 * reread partition info */
429 int degraded; /* whether md should consider
433 atomic_t recovery_active; /* blocks scheduled, but not written */
434 wait_queue_head_t recovery_wait;
435 sector_t recovery_cp;
436 sector_t resync_min; /* user requested sync
438 sector_t resync_max; /* resync should pause
439 * when it gets here */
441 struct kernfs_node *sysfs_state; /* handle for 'array_state'
444 struct kernfs_node *sysfs_action; /* handle for 'sync_action' */
445 struct kernfs_node *sysfs_completed; /*handle for 'sync_completed' */
446 struct kernfs_node *sysfs_degraded; /*handle for 'degraded' */
447 struct kernfs_node *sysfs_level; /*handle for 'level' */
449 /* used for delayed sysfs removal */
450 struct work_struct del_work;
451 /* used for register new sync thread */
452 struct work_struct sync_work;
455 * flush_bio transition from NULL to !NULL
456 * rdev superblocks, events
457 * clearing MD_CHANGE_*
458 * in_sync - and related safemode and MD_CHANGE changes
459 * pers (also protected by reconfig_mutex and pending IO).
461 * clearing ->bitmap_info.file
462 * changing ->resync_{min,max}
463 * setting MD_RECOVERY_RUNNING (which interacts with resync_{min,max})
466 wait_queue_head_t sb_wait; /* for waiting on superblock updates */
467 atomic_t pending_writes; /* number of active superblock writes */
469 unsigned int safemode; /* if set, update "clean" superblock
470 * when no writes pending.
472 unsigned int safemode_delay;
473 struct timer_list safemode_timer;
474 struct percpu_ref writes_pending;
475 int sync_checkers; /* # of threads checking writes_pending */
476 struct request_queue *queue; /* for plugging ... */
478 struct bitmap *bitmap; /* the bitmap for the device */
480 struct file *file; /* the bitmap file */
481 loff_t offset; /* offset from superblock of
482 * start of bitmap. May be
483 * negative, but not '0'
484 * For external metadata, offset
485 * from start of device.
487 unsigned long space; /* space available at this offset */
488 loff_t default_offset; /* this is the offset to use when
489 * hot-adding a bitmap. It should
490 * eventually be settable by sysfs.
492 unsigned long default_space; /* space available at
495 unsigned long chunksize;
496 unsigned long daemon_sleep; /* how many jiffies between updates? */
497 unsigned long max_write_behind; /* write-behind mode */
499 int nodes; /* Maximum number of nodes in the cluster */
500 char cluster_name[64]; /* Name of the cluster */
503 atomic_t max_corr_read_errors; /* max read retries */
504 struct list_head all_mddevs;
506 const struct attribute_group *to_remove;
508 struct bio_set bio_set;
509 struct bio_set sync_set; /* for sync operations like
510 * metadata and bitmap writes
512 struct bio_set io_clone_set;
514 /* Generic flush handling.
515 * The last to finish preflush schedules a worker to submit
516 * the rest of the request (without the REQ_PREFLUSH flag).
518 struct bio *flush_bio;
519 atomic_t flush_pending;
520 ktime_t start_flush, prev_flush_start; /* prev_flush_start is when the previous completed
523 struct work_struct flush_work;
524 struct work_struct event_work; /* used by dm to report failure event */
525 mempool_t *serial_info_pool;
526 void (*sync_super)(struct mddev *mddev, struct md_rdev *rdev);
527 struct md_cluster_info *cluster_info;
528 unsigned int good_device_nr; /* good device num within cluster raid */
529 unsigned int noio_flag; /* for memalloc scope API */
532 * Temporarily store rdev that will be finally removed when
533 * reconfig_mutex is unlocked, protected by reconfig_mutex.
535 struct list_head deleting;
537 /* Used to synchronize idle and frozen for action_store() */
538 struct mutex sync_mutex;
539 /* The sequence number for sync thread */
542 bool has_superblocks:1;
543 bool fail_last_dev:1;
544 bool serialize_policy:1;
547 enum recovery_flags {
549 * If neither SYNC or RESHAPE are set, then it is a recovery.
551 MD_RECOVERY_RUNNING, /* a thread is running, or about to be started */
552 MD_RECOVERY_SYNC, /* actually doing a resync, not a recovery */
553 MD_RECOVERY_RECOVER, /* doing recovery, or need to try it. */
554 MD_RECOVERY_INTR, /* resync needs to be aborted for some reason */
555 MD_RECOVERY_DONE, /* thread is done and is waiting to be reaped */
556 MD_RECOVERY_NEEDED, /* we might need to start a resync/recover */
557 MD_RECOVERY_REQUESTED, /* user-space has requested a sync (used with SYNC) */
558 MD_RECOVERY_CHECK, /* user-space request for check-only, no repair */
559 MD_RECOVERY_RESHAPE, /* A reshape is happening */
560 MD_RECOVERY_FROZEN, /* User request to abort, and not restart, any action */
561 MD_RECOVERY_ERROR, /* sync-action interrupted because io-error */
562 MD_RECOVERY_WAIT, /* waiting for pers->start() to finish */
563 MD_RESYNCING_REMOTE, /* remote node is running resync thread */
566 static inline int __must_check mddev_lock(struct mddev *mddev)
568 return mutex_lock_interruptible(&mddev->reconfig_mutex);
571 /* Sometimes we need to take the lock in a situation where
572 * failure due to interrupts is not acceptable.
574 static inline void mddev_lock_nointr(struct mddev *mddev)
576 mutex_lock(&mddev->reconfig_mutex);
579 static inline int mddev_trylock(struct mddev *mddev)
581 return mutex_trylock(&mddev->reconfig_mutex);
583 extern void mddev_unlock(struct mddev *mddev);
585 static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors)
587 atomic_add(nr_sectors, &bdev->bd_disk->sync_io);
590 static inline void md_sync_acct_bio(struct bio *bio, unsigned long nr_sectors)
592 md_sync_acct(bio->bi_bdev, nr_sectors);
595 struct md_personality
599 struct list_head list;
600 struct module *owner;
601 bool __must_check (*make_request)(struct mddev *mddev, struct bio *bio);
603 * start up works that do NOT require md_thread. tasks that
604 * requires md_thread should go into start()
606 int (*run)(struct mddev *mddev);
607 /* start up works that require md threads */
608 int (*start)(struct mddev *mddev);
609 void (*free)(struct mddev *mddev, void *priv);
610 void (*status)(struct seq_file *seq, struct mddev *mddev);
611 /* error_handler must set ->faulty and clear ->in_sync
612 * if appropriate, and should abort recovery if needed
614 void (*error_handler)(struct mddev *mddev, struct md_rdev *rdev);
615 int (*hot_add_disk) (struct mddev *mddev, struct md_rdev *rdev);
616 int (*hot_remove_disk) (struct mddev *mddev, struct md_rdev *rdev);
617 int (*spare_active) (struct mddev *mddev);
618 sector_t (*sync_request)(struct mddev *mddev, sector_t sector_nr, int *skipped);
619 int (*resize) (struct mddev *mddev, sector_t sectors);
620 sector_t (*size) (struct mddev *mddev, sector_t sectors, int raid_disks);
621 int (*check_reshape) (struct mddev *mddev);
622 int (*start_reshape) (struct mddev *mddev);
623 void (*finish_reshape) (struct mddev *mddev);
624 void (*update_reshape_pos) (struct mddev *mddev);
625 /* quiesce suspends or resumes internal processing.
626 * 1 - stop new actions and wait for action io to complete
627 * 0 - return to normal behaviour
629 void (*quiesce) (struct mddev *mddev, int quiesce);
630 /* takeover is used to transition an array from one
631 * personality to another. The new personality must be able
632 * to handle the data in the current layout.
633 * e.g. 2drive raid1 -> 2drive raid5
634 * ndrive raid5 -> degraded n+1drive raid6 with special layout
635 * If the takeover succeeds, a new 'private' structure is returned.
636 * This needs to be installed and then ->run used to activate the
639 void *(*takeover) (struct mddev *mddev);
640 /* Changes the consistency policy of an active array. */
641 int (*change_consistency_policy)(struct mddev *mddev, const char *buf);
644 struct md_sysfs_entry {
645 struct attribute attr;
646 ssize_t (*show)(struct mddev *, char *);
647 ssize_t (*store)(struct mddev *, const char *, size_t);
649 extern const struct attribute_group md_bitmap_group;
651 static inline struct kernfs_node *sysfs_get_dirent_safe(struct kernfs_node *sd, char *name)
654 return sysfs_get_dirent(sd, name);
657 static inline void sysfs_notify_dirent_safe(struct kernfs_node *sd)
660 sysfs_notify_dirent(sd);
663 static inline char * mdname (struct mddev * mddev)
665 return mddev->gendisk ? mddev->gendisk->disk_name : "mdX";
668 static inline int sysfs_link_rdev(struct mddev *mddev, struct md_rdev *rdev)
671 if (!test_bit(Replacement, &rdev->flags) &&
672 !test_bit(Journal, &rdev->flags) &&
674 sprintf(nm, "rd%d", rdev->raid_disk);
675 return sysfs_create_link(&mddev->kobj, &rdev->kobj, nm);
680 static inline void sysfs_unlink_rdev(struct mddev *mddev, struct md_rdev *rdev)
683 if (!test_bit(Replacement, &rdev->flags) &&
684 !test_bit(Journal, &rdev->flags) &&
686 sprintf(nm, "rd%d", rdev->raid_disk);
687 sysfs_remove_link(&mddev->kobj, nm);
692 * iterates through some rdev ringlist. It's safe to remove the
693 * current 'rdev'. Dont touch 'tmp' though.
695 #define rdev_for_each_list(rdev, tmp, head) \
696 list_for_each_entry_safe(rdev, tmp, head, same_set)
699 * iterates through the 'same array disks' ringlist
701 #define rdev_for_each(rdev, mddev) \
702 list_for_each_entry(rdev, &((mddev)->disks), same_set)
704 #define rdev_for_each_safe(rdev, tmp, mddev) \
705 list_for_each_entry_safe(rdev, tmp, &((mddev)->disks), same_set)
707 #define rdev_for_each_rcu(rdev, mddev) \
708 list_for_each_entry_rcu(rdev, &((mddev)->disks), same_set)
711 void (*run) (struct md_thread *thread);
713 wait_queue_head_t wqueue;
715 struct task_struct *tsk;
716 unsigned long timeout;
722 struct bio *orig_bio;
723 unsigned long start_time;
724 struct bio bio_clone;
727 #define THREAD_WAKEUP 0
729 static inline void safe_put_page(struct page *p)
734 extern int register_md_personality(struct md_personality *p);
735 extern int unregister_md_personality(struct md_personality *p);
736 extern int register_md_cluster_operations(struct md_cluster_operations *ops,
737 struct module *module);
738 extern int unregister_md_cluster_operations(void);
739 extern int md_setup_cluster(struct mddev *mddev, int nodes);
740 extern void md_cluster_stop(struct mddev *mddev);
741 extern struct md_thread *md_register_thread(
742 void (*run)(struct md_thread *thread),
745 extern void md_unregister_thread(struct mddev *mddev, struct md_thread __rcu **threadp);
746 extern void md_wakeup_thread(struct md_thread __rcu *thread);
747 extern void md_check_recovery(struct mddev *mddev);
748 extern void md_reap_sync_thread(struct mddev *mddev);
749 extern bool md_write_start(struct mddev *mddev, struct bio *bi);
750 extern void md_write_inc(struct mddev *mddev, struct bio *bi);
751 extern void md_write_end(struct mddev *mddev);
752 extern void md_done_sync(struct mddev *mddev, int blocks, int ok);
753 extern void md_error(struct mddev *mddev, struct md_rdev *rdev);
754 extern void md_finish_reshape(struct mddev *mddev);
755 void md_submit_discard_bio(struct mddev *mddev, struct md_rdev *rdev,
756 struct bio *bio, sector_t start, sector_t size);
757 void md_account_bio(struct mddev *mddev, struct bio **bio);
759 extern bool __must_check md_flush_request(struct mddev *mddev, struct bio *bio);
760 extern void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
761 sector_t sector, int size, struct page *page);
762 extern int md_super_wait(struct mddev *mddev);
763 extern int sync_page_io(struct md_rdev *rdev, sector_t sector, int size,
764 struct page *page, blk_opf_t opf, bool metadata_op);
765 extern void md_do_sync(struct md_thread *thread);
766 extern void md_new_event(void);
767 extern void md_allow_write(struct mddev *mddev);
768 extern void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev);
769 extern void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors);
770 extern int md_check_no_bitmap(struct mddev *mddev);
771 extern int md_integrity_register(struct mddev *mddev);
772 extern int md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev);
773 extern int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale);
775 extern int mddev_init(struct mddev *mddev);
776 extern void mddev_destroy(struct mddev *mddev);
777 struct mddev *md_alloc(dev_t dev, char *name);
778 void mddev_put(struct mddev *mddev);
779 extern int md_run(struct mddev *mddev);
780 extern int md_start(struct mddev *mddev);
781 extern void md_stop(struct mddev *mddev);
782 extern void md_stop_writes(struct mddev *mddev);
783 extern int md_rdev_init(struct md_rdev *rdev);
784 extern void md_rdev_clear(struct md_rdev *rdev);
786 extern void md_handle_request(struct mddev *mddev, struct bio *bio);
787 extern int mddev_suspend(struct mddev *mddev, bool interruptible);
788 extern void mddev_resume(struct mddev *mddev);
790 extern void md_reload_sb(struct mddev *mddev, int raid_disk);
791 extern void md_update_sb(struct mddev *mddev, int force);
792 extern void mddev_create_serial_pool(struct mddev *mddev, struct md_rdev *rdev);
793 extern void mddev_destroy_serial_pool(struct mddev *mddev,
794 struct md_rdev *rdev);
795 struct md_rdev *md_find_rdev_nr_rcu(struct mddev *mddev, int nr);
796 struct md_rdev *md_find_rdev_rcu(struct mddev *mddev, dev_t dev);
798 static inline bool is_rdev_broken(struct md_rdev *rdev)
800 return !disk_live(rdev->bdev->bd_disk);
803 static inline void rdev_dec_pending(struct md_rdev *rdev, struct mddev *mddev)
805 int faulty = test_bit(Faulty, &rdev->flags);
806 if (atomic_dec_and_test(&rdev->nr_pending) && faulty) {
807 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
808 md_wakeup_thread(mddev->thread);
812 extern struct md_cluster_operations *md_cluster_ops;
813 static inline int mddev_is_clustered(struct mddev *mddev)
815 return mddev->cluster_info && mddev->bitmap_info.nodes > 1;
818 /* clear unsupported mddev_flags */
819 static inline void mddev_clear_unsupported_flags(struct mddev *mddev,
820 unsigned long unsupported_flags)
822 mddev->flags &= ~unsupported_flags;
825 static inline void mddev_check_write_zeroes(struct mddev *mddev, struct bio *bio)
827 if (bio_op(bio) == REQ_OP_WRITE_ZEROES &&
828 !bio->bi_bdev->bd_disk->queue->limits.max_write_zeroes_sectors)
829 mddev->queue->limits.max_write_zeroes_sectors = 0;
832 static inline int mddev_suspend_and_lock(struct mddev *mddev)
836 ret = mddev_suspend(mddev, true);
840 ret = mddev_lock(mddev);
847 static inline void mddev_suspend_and_lock_nointr(struct mddev *mddev)
849 mddev_suspend(mddev, false);
850 mutex_lock(&mddev->reconfig_mutex);
853 static inline void mddev_unlock_and_resume(struct mddev *mddev)
859 struct mdu_array_info_s;
860 struct mdu_disk_info_s;
862 extern int mdp_major;
863 extern struct workqueue_struct *md_bitmap_wq;
864 void md_autostart_arrays(int part);
865 int md_set_array_info(struct mddev *mddev, struct mdu_array_info_s *info);
866 int md_add_new_disk(struct mddev *mddev, struct mdu_disk_info_s *info);
867 int do_md_run(struct mddev *mddev);
869 extern const struct block_device_operations md_fops;
871 #endif /* _MD_MD_H */