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1/* SPDX-License-Identifier: GPL-2.0-or-later */2/*3 md.h : kernel internal structure of the Linux MD driver4 Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman5 6*/7 8#ifndef _MD_MD_H9#define _MD_MD_H10 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 than28 * "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 because31 * Commit: 4a27446f3e39 ("[SCSI] modify scsi to handle new fail fast flags.")32 * seems to suggest that the errors it avoids retrying should usually33 * be retried.34 */35#define MD_FAILFAST (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT)36 37/* Status of sync thread. */38enum sync_action {39 /*40 * Represent by MD_RECOVERY_SYNC, start when:41 * 1) after assemble, sync data from first rdev to other copies, this42 * must be done first before other sync actions and will only execute43 * once;44 * 2) resize the array(notice that this is not reshape), sync data for45 * 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 or51 * available copies from other rdev;52 * 2) for new member disk while the array is degraded, sync data from53 * other rdev;54 * 3) reassemble after power failure or re-add a hot removed rdev, sync55 * 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 api61 * sync_action, used to check if data copies from differenct rdev are62 * the same. The number of mismatch sectors will be exported to user63 * by sysfs api mismatch_cnt;64 */65 ACTION_CHECK,66 /*67 * Represent by MD_RECOVERY_SYNC | MD_RECOVERY_REQUESTED, start when68 * user echo "repair" to sysfs api sync_action, usually paired with69 * ACTION_CHECK, used to force syncing data once user found that there70 * are inconsistent data,71 */72 ACTION_REPAIR,73 /*74 * Represent by MD_RECOVERY_RESHAPE, start when new member disk is added75 * to the conf, notice that this is different from spares or76 * replacement;77 */78 ACTION_RESHAPE,79 /*80 * Represent by MD_RECOVERY_FROZEN, can be set by sysfs api sync_action81 * or internal usage like setting the array read-only, will forbid above82 * 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 */95struct 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' device103 */104struct 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 is113 * being used to store the metadata (superblock/bitmap) which114 * 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==0133 * Fully working: faulty==0 in_sync==1134 * Working, but not135 * in sync with array136 * faulty==0 in_sync==0137 *138 * It can never have faulty==1, in_sync==1139 * This reduces the burden of testing multiple flags in many cases140 */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 in148 * the array after a level-change completes.149 */150 int saved_raid_disk; /* role that device used to have in the151 * array and could again if we did a partial152 * resync from the bitmap153 */154 union {155 sector_t recovery_offset;/* If this device has been partially156 * recovered, this is where we were157 * up to.158 */159 sector_t journal_tail; /* If this device is a journal device,160 * this is the journal tail (journal161 * recovery start point)162 */163 };164 165 atomic_t nr_pending; /* number of pending requests.166 * only maintained for arrays that167 * support hot removal168 */169 atomic_t read_errors; /* number of consecutive read errors that170 * we have tried to ignore.171 */172 time64_t last_read_error; /* monotonic time since our173 * last read error174 */175 atomic_t corrected_errors; /* number of corrected read errors,176 * for reporting to userspace and storing177 * 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};197enum 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 a201 * bitmap-based recovery to get fully in sync.202 * The bit is only meaningful before device203 * 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 yet208 * been acknowledged by the metadata209 * handler, so don't allow writes210 * until it is cleared */211 WriteErrorSeen, /* A write error has been seen on this212 * device213 */214 FaultRecorded, /* Intermediate state for clearing215 * Blocked. The Fault is/will-be216 * recorded in the metadata, but that217 * metadata hasn't been stored safely218 * on disk yet.219 */220 BlockedBadBlocks, /* A writer is blocked because they221 * found an unacknowledged bad-block.222 * This can safely be cleared at any223 * time, and the writer will re-check.224 * It may be set at any time, and at225 * worst the writer will timeout and226 * re-check. So setting it as227 * accurately as possible is good, but228 * not absolutely critical.229 */230 WantReplacement, /* This device is a candidate to be231 * hot-replaced, either because it has232 * reported some faults, or because233 * of explicit request.234 */235 Replacement, /* This device is a replacement for236 * a want_replacement device with same237 * raid_disk number.238 */239 Candidate, /* For clustered environments only:240 * This device is seen locally but not241 * by the whole cluster242 */243 Journal, /* This device is used as journal for244 * raid-5/6.245 * Usually, this device should be faster246 * than other devices in the array247 */248 ClusterRemove,249 ExternalBbl, /* External metadata provides bad250 * block management for a disk251 */252 FailFast, /* Minimal retries should be attempted on253 * this device, so use REQ_FAILFAST_DEV.254 * Also don't try to repair failed reads.255 * It is expects that no bad block log256 * is present.257 */258 LastDev, /* Seems to be the last working dev as259 * it didn't fail, so don't use FailFast260 * any more for metadata261 */262 CollisionCheck, /*263 * check if there is collision between raid1264 * serial bios.265 */266 Nonrot, /* non-rotational device (SSD) */267};268 269static 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 283static 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 292extern int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors,293 int is_new);294extern int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors,295 int is_new);296struct 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 took305 * resync lock, need to release the lock.306 * @MD_FAILFAST_SUPPORTED: Using MD_FAILFAST on metadata writes is supported as307 * calls to md_error() will never cause the array to308 * 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 that312 * 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 deleted315 *316 * change UNSUPPORTED_MDDEV_FLAGS for each array type if new flag is added317 */318enum 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 332enum 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 8340/* record current range of serialize IOs */341struct 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 but350 * also has some overloaded values.351 */352enum {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 363struct 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 deletes377 * are happening, so run/378 * takeover/stop are not safe379 */380 struct gendisk *gendisk;381 382 struct kobject kobj;383 int hold_active;384#define UNTIL_IOCTL 1385#define UNTIL_STOP 2386 387 /* Superblock information */388 int major_version,389 minor_version,390 patch_version;391 int persistent;392 int external; /* metadata is393 * 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 of402 * component devices */403 sector_t array_sectors; /* exported array size */404 int external_size; /* size managed405 * externally */406 __u64 events;407 /* If the last 'event' was simply a clean->dirty transition, and408 * we didn't write it to the spares, then it is safe and simple409 * 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 the417 * 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 even431 * when the sync thread is "frozen" (interrupted) or "idle" (stopped432 * 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 track437 * how much resync has been completed. So we occasionally pause until438 * 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 value440 * 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 where450 * parity/replica mismatch found451 */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 particular467 * device) will fail due to a read error on the source device, it468 * takes a copy of this number and does not attempt recovery again469 * 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', so475 * 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 interactions478 * with disk->open_mutex.479 * Lock ordering is:480 * reconfig_mutex -> disk->open_mutex481 * disk->open_mutex -> open_mutex: e.g. __blkdev_get -> md_open482 */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 to489 * reread partition info */490 int degraded; /* whether md should consider491 * adding a spare492 */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 sync498 * starts here */499 sector_t resync_max; /* resync should pause500 * 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 !NULL517 * rdev superblocks, events518 * clearing MD_CHANGE_*519 * in_sync - and related safemode and MD_CHANGE changes520 * pers (also protected by reconfig_mutex and pending IO).521 * clearing ->bitmap522 * clearing ->bitmap_info.file523 * 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" superblock531 * 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 of543 * start of bitmap. May be544 * negative, but not '0'545 * For external metadata, offset546 * 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 when550 * hot-adding a bitmap. It should551 * eventually be settable by sysfs.552 */553 unsigned long default_space; /* space available at554 * 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 like571 * metadata and bitmap writes572 */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 when584 * 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 596enum 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 be601 * 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 is628 * 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 639enum md_ro_state {640 MD_RDWR,641 MD_RDONLY,642 MD_AUTO_READ,643 MD_MAX_STATE644};645 646static inline bool md_is_rdwr(struct mddev *mddev)647{648 return (mddev->ro == MD_RDWR);649}650 651static 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 670static 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 where676 * failure due to interrupts is not acceptable.677 */678static inline void mddev_lock_nointr(struct mddev *mddev)679{680 mutex_lock(&mddev->reconfig_mutex);681}682 683static inline int mddev_trylock(struct mddev *mddev)684{685 return mutex_trylock(&mddev->reconfig_mutex);686}687extern void mddev_unlock(struct mddev *mddev);688 689static 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 695static 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 700struct md_personality701{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 that709 * 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_sync717 * if appropriate, and should abort recovery if needed718 */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 complete734 * 0 - return to normal behaviour735 */736 void (*quiesce) (struct mddev *mddev, int quiesce);737 /* takeover is used to transition an array from one738 * personality to another. The new personality must be able739 * to handle the data in the current layout.740 * e.g. 2drive raid1 -> 2drive raid5741 * ndrive raid5 -> degraded n+1drive raid6 with special layout742 * If the takeover succeeds, a new 'private' structure is returned.743 * This needs to be installed and then ->run used to activate the744 * 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 751struct 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};756extern const struct attribute_group md_bitmap_group;757 758static 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}764static inline void sysfs_notify_dirent_safe(struct kernfs_node *sd)765{766 if (sd)767 sysfs_notify_dirent(sd);768}769 770static inline char * mdname (struct mddev * mddev)771{772 return mddev->gendisk ? mddev->gendisk->disk_name : "mdX";773}774 775static 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 } else784 return 0;785}786 787static 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 the800 * 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' ringlist807 */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 817struct 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 827struct 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 0835 836static inline void safe_put_page(struct page *p)837{838 if (p) put_page(p);839}840 841extern int register_md_personality(struct md_personality *p);842extern int unregister_md_personality(struct md_personality *p);843extern int register_md_cluster_operations(const struct md_cluster_operations *ops,844 struct module *module);845extern int unregister_md_cluster_operations(void);846extern int md_setup_cluster(struct mddev *mddev, int nodes);847extern void md_cluster_stop(struct mddev *mddev);848extern struct md_thread *md_register_thread(849 void (*run)(struct md_thread *thread),850 struct mddev *mddev,851 const char *name);852extern void md_unregister_thread(struct mddev *mddev, struct md_thread __rcu **threadp);853extern void md_wakeup_thread(struct md_thread __rcu *thread);854extern void md_check_recovery(struct mddev *mddev);855extern void md_reap_sync_thread(struct mddev *mddev);856extern enum sync_action md_sync_action(struct mddev *mddev);857extern enum sync_action md_sync_action_by_name(const char *page);858extern const char *md_sync_action_name(enum sync_action action);859extern void md_write_start(struct mddev *mddev, struct bio *bi);860extern void md_write_inc(struct mddev *mddev, struct bio *bi);861extern void md_write_end(struct mddev *mddev);862extern void md_done_sync(struct mddev *mddev, int blocks, int ok);863extern void md_error(struct mddev *mddev, struct md_rdev *rdev);864extern void md_finish_reshape(struct mddev *mddev);865void md_submit_discard_bio(struct mddev *mddev, struct md_rdev *rdev,866 struct bio *bio, sector_t start, sector_t size);867void md_account_bio(struct mddev *mddev, struct bio **bio);868void md_free_cloned_bio(struct bio *bio);869 870extern bool __must_check md_flush_request(struct mddev *mddev, struct bio *bio);871extern void md_super_write(struct mddev *mddev, struct md_rdev *rdev,872 sector_t sector, int size, struct page *page);873extern int md_super_wait(struct mddev *mddev);874extern int sync_page_io(struct md_rdev *rdev, sector_t sector, int size,875 struct page *page, blk_opf_t opf, bool metadata_op);876extern void md_do_sync(struct md_thread *thread);877extern void md_new_event(void);878extern void md_allow_write(struct mddev *mddev);879extern void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev);880extern void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors);881extern int md_check_no_bitmap(struct mddev *mddev);882extern int md_integrity_register(struct mddev *mddev);883extern int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale);884 885extern int mddev_init(struct mddev *mddev);886extern void mddev_destroy(struct mddev *mddev);887void md_init_stacking_limits(struct queue_limits *lim);888struct mddev *md_alloc(dev_t dev, char *name);889void mddev_put(struct mddev *mddev);890extern int md_run(struct mddev *mddev);891extern int md_start(struct mddev *mddev);892extern void md_stop(struct mddev *mddev);893extern void md_stop_writes(struct mddev *mddev);894extern int md_rdev_init(struct md_rdev *rdev);895extern void md_rdev_clear(struct md_rdev *rdev);896 897extern bool md_handle_request(struct mddev *mddev, struct bio *bio);898extern int mddev_suspend(struct mddev *mddev, bool interruptible);899extern void mddev_resume(struct mddev *mddev);900extern void md_idle_sync_thread(struct mddev *mddev);901extern void md_frozen_sync_thread(struct mddev *mddev);902extern void md_unfrozen_sync_thread(struct mddev *mddev);903 904extern void md_reload_sb(struct mddev *mddev, int raid_disk);905extern void md_update_sb(struct mddev *mddev, int force);906extern void mddev_create_serial_pool(struct mddev *mddev, struct md_rdev *rdev);907extern void mddev_destroy_serial_pool(struct mddev *mddev,908 struct md_rdev *rdev);909struct md_rdev *md_find_rdev_nr_rcu(struct mddev *mddev, int nr);910struct md_rdev *md_find_rdev_rcu(struct mddev *mddev, dev_t dev);911 912static inline bool is_rdev_broken(struct md_rdev *rdev)913{914 return !disk_live(rdev->bdev->bd_disk);915}916 917static 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 926extern const struct md_cluster_operations *md_cluster_ops;927static 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 */933static inline void mddev_clear_unsupported_flags(struct mddev *mddev,934 unsigned long unsupported_flags)935{936 mddev->flags &= ~unsupported_flags;937}938 939static 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 946static 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 961static inline void mddev_suspend_and_lock_nointr(struct mddev *mddev)962{963 mddev_suspend(mddev, false);964 mutex_lock(&mddev->reconfig_mutex);965}966 967static inline void mddev_unlock_and_resume(struct mddev *mddev)968{969 mddev_unlock(mddev);970 mddev_resume(mddev);971}972 973struct mdu_array_info_s;974struct mdu_disk_info_s;975 976extern int mdp_major;977extern struct workqueue_struct *md_bitmap_wq;978void md_autostart_arrays(int part);979int md_set_array_info(struct mddev *mddev, struct mdu_array_info_s *info);980int md_add_new_disk(struct mddev *mddev, struct mdu_disk_info_s *info);981int do_md_run(struct mddev *mddev);982#define MDDEV_STACK_INTEGRITY (1u << 0)983int mddev_stack_rdev_limits(struct mddev *mddev, struct queue_limits *lim,984 unsigned int flags);985int mddev_stack_new_rdev(struct mddev *mddev, struct md_rdev *rdev);986void mddev_update_io_opt(struct mddev *mddev, unsigned int nr_stripes);987 988extern 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 */993static inline bool mddev_is_dm(struct mddev *mddev)994{995 return !mddev->gendisk;996}997 998static 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 1005#define mddev_add_trace_msg(mddev, fmt, args...) \1006do { \1007 if (!mddev_is_dm(mddev)) \1008 blk_add_trace_msg((mddev)->gendisk->queue, fmt, ##args); \1009} while (0)1010 1011#endif /* _MD_MD_H */1012