linux/drivers/md/md.h
<<
>>
Prefs
   1/*
   2   md.h : kernel internal structure of the Linux MD driver
   3          Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman
   4          
   5   This program is free software; you can redistribute it and/or modify
   6   it under the terms of the GNU General Public License as published by
   7   the Free Software Foundation; either version 2, or (at your option)
   8   any later version.
   9   
  10   You should have received a copy of the GNU General Public License
  11   (for example /usr/src/linux/COPYING); if not, write to the Free
  12   Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  
  13*/
  14
  15#ifndef _MD_MD_H
  16#define _MD_MD_H
  17
  18#include <linux/blkdev.h>
  19#include <linux/kobject.h>
  20#include <linux/list.h>
  21#include <linux/mm.h>
  22#include <linux/mutex.h>
  23#include <linux/timer.h>
  24#include <linux/wait.h>
  25#include <linux/workqueue.h>
  26
  27#define MaxSector (~(sector_t)0)
  28
  29/* Bad block numbers are stored sorted in a single page.
  30 * 64bits is used for each block or extent.
  31 * 54 bits are sector number, 9 bits are extent size,
  32 * 1 bit is an 'acknowledged' flag.
  33 */
  34#define MD_MAX_BADBLOCKS        (PAGE_SIZE/8)
  35
  36/*
  37 * MD's 'extended' device
  38 */
  39struct md_rdev {
  40        struct list_head same_set;      /* RAID devices within the same set */
  41
  42        sector_t sectors;               /* Device size (in 512bytes sectors) */
  43        struct mddev *mddev;            /* RAID array if running */
  44        int last_events;                /* IO event timestamp */
  45
  46        /*
  47         * If meta_bdev is non-NULL, it means that a separate device is
  48         * being used to store the metadata (superblock/bitmap) which
  49         * would otherwise be contained on the same device as the data (bdev).
  50         */
  51        struct block_device *meta_bdev;
  52        struct block_device *bdev;      /* block device handle */
  53
  54        struct page     *sb_page, *bb_page;
  55        int             sb_loaded;
  56        __u64           sb_events;
  57        sector_t        data_offset;    /* start of data in array */
  58        sector_t        new_data_offset;/* only relevant while reshaping */
  59        sector_t        sb_start;       /* offset of the super block (in 512byte sectors) */
  60        int             sb_size;        /* bytes in the superblock */
  61        int             preferred_minor;        /* autorun support */
  62
  63        struct kobject  kobj;
  64
  65        /* A device can be in one of three states based on two flags:
  66         * Not working:   faulty==1 in_sync==0
  67         * Fully working: faulty==0 in_sync==1
  68         * Working, but not
  69         * in sync with array
  70         *                faulty==0 in_sync==0
  71         *
  72         * It can never have faulty==1, in_sync==1
  73         * This reduces the burden of testing multiple flags in many cases
  74         */
  75
  76        unsigned long   flags;  /* bit set of 'enum flag_bits' bits. */
  77        wait_queue_head_t blocked_wait;
  78
  79        int desc_nr;                    /* descriptor index in the superblock */
  80        int raid_disk;                  /* role of device in array */
  81        int new_raid_disk;              /* role that the device will have in
  82                                         * the array after a level-change completes.
  83                                         */
  84        int saved_raid_disk;            /* role that device used to have in the
  85                                         * array and could again if we did a partial
  86                                         * resync from the bitmap
  87                                         */
  88        sector_t        recovery_offset;/* If this device has been partially
  89                                         * recovered, this is where we were
  90                                         * up to.
  91                                         */
  92
  93        atomic_t        nr_pending;     /* number of pending requests.
  94                                         * only maintained for arrays that
  95                                         * support hot removal
  96                                         */
  97        atomic_t        read_errors;    /* number of consecutive read errors that
  98                                         * we have tried to ignore.
  99                                         */
 100        struct timespec last_read_error;        /* monotonic time since our
 101                                                 * last read error
 102                                                 */
 103        atomic_t        corrected_errors; /* number of corrected read errors,
 104                                           * for reporting to userspace and storing
 105                                           * in superblock.
 106                                           */
 107        struct work_struct del_work;    /* used for delayed sysfs removal */
 108
 109        struct sysfs_dirent *sysfs_state; /* handle for 'state'
 110                                           * sysfs entry */
 111
 112        struct badblocks {
 113                int     count;          /* count of bad blocks */
 114                int     unacked_exist;  /* there probably are unacknowledged
 115                                         * bad blocks.  This is only cleared
 116                                         * when a read discovers none
 117                                         */
 118                int     shift;          /* shift from sectors to block size
 119                                         * a -ve shift means badblocks are
 120                                         * disabled.*/
 121                u64     *page;          /* badblock list */
 122                int     changed;
 123                seqlock_t lock;
 124
 125                sector_t sector;
 126                sector_t size;          /* in sectors */
 127        } badblocks;
 128};
 129enum flag_bits {
 130        Faulty,                 /* device is known to have a fault */
 131        In_sync,                /* device is in_sync with rest of array */
 132        Unmerged,               /* device is being added to array and should
 133                                 * be considerred for bvec_merge_fn but not
 134                                 * yet for actual IO
 135                                 */
 136        WriteMostly,            /* Avoid reading if at all possible */
 137        AutoDetected,           /* added by auto-detect */
 138        Blocked,                /* An error occurred but has not yet
 139                                 * been acknowledged by the metadata
 140                                 * handler, so don't allow writes
 141                                 * until it is cleared */
 142        WriteErrorSeen,         /* A write error has been seen on this
 143                                 * device
 144                                 */
 145        FaultRecorded,          /* Intermediate state for clearing
 146                                 * Blocked.  The Fault is/will-be
 147                                 * recorded in the metadata, but that
 148                                 * metadata hasn't been stored safely
 149                                 * on disk yet.
 150                                 */
 151        BlockedBadBlocks,       /* A writer is blocked because they
 152                                 * found an unacknowledged bad-block.
 153                                 * This can safely be cleared at any
 154                                 * time, and the writer will re-check.
 155                                 * It may be set at any time, and at
 156                                 * worst the writer will timeout and
 157                                 * re-check.  So setting it as
 158                                 * accurately as possible is good, but
 159                                 * not absolutely critical.
 160                                 */
 161        WantReplacement,        /* This device is a candidate to be
 162                                 * hot-replaced, either because it has
 163                                 * reported some faults, or because
 164                                 * of explicit request.
 165                                 */
 166        Replacement,            /* This device is a replacement for
 167                                 * a want_replacement device with same
 168                                 * raid_disk number.
 169                                 */
 170};
 171
 172#define BB_LEN_MASK     (0x00000000000001FFULL)
 173#define BB_OFFSET_MASK  (0x7FFFFFFFFFFFFE00ULL)
 174#define BB_ACK_MASK     (0x8000000000000000ULL)
 175#define BB_MAX_LEN      512
 176#define BB_OFFSET(x)    (((x) & BB_OFFSET_MASK) >> 9)
 177#define BB_LEN(x)       (((x) & BB_LEN_MASK) + 1)
 178#define BB_ACK(x)       (!!((x) & BB_ACK_MASK))
 179#define BB_MAKE(a, l, ack) (((a)<<9) | ((l)-1) | ((u64)(!!(ack)) << 63))
 180
 181extern int md_is_badblock(struct badblocks *bb, sector_t s, int sectors,
 182                          sector_t *first_bad, int *bad_sectors);
 183static inline int is_badblock(struct md_rdev *rdev, sector_t s, int sectors,
 184                              sector_t *first_bad, int *bad_sectors)
 185{
 186        if (unlikely(rdev->badblocks.count)) {
 187                int rv = md_is_badblock(&rdev->badblocks, rdev->data_offset + s,
 188                                        sectors,
 189                                        first_bad, bad_sectors);
 190                if (rv)
 191                        *first_bad -= rdev->data_offset;
 192                return rv;
 193        }
 194        return 0;
 195}
 196extern int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
 197                              int is_new);
 198extern int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
 199                                int is_new);
 200extern void md_ack_all_badblocks(struct badblocks *bb);
 201
 202struct mddev {
 203        void                            *private;
 204        struct md_personality           *pers;
 205        dev_t                           unit;
 206        int                             md_minor;
 207        struct list_head                disks;
 208        unsigned long                   flags;
 209#define MD_CHANGE_DEVS  0       /* Some device status has changed */
 210#define MD_CHANGE_CLEAN 1       /* transition to or from 'clean' */
 211#define MD_CHANGE_PENDING 2     /* switch from 'clean' to 'active' in progress */
 212#define MD_ARRAY_FIRST_USE 3    /* First use of array, needs initialization */
 213
 214        int                             suspended;
 215        atomic_t                        active_io;
 216        int                             ro;
 217        int                             sysfs_active; /* set when sysfs deletes
 218                                                       * are happening, so run/
 219                                                       * takeover/stop are not safe
 220                                                       */
 221        int                             ready; /* See when safe to pass 
 222                                                * IO requests down */
 223        struct gendisk                  *gendisk;
 224
 225        struct kobject                  kobj;
 226        int                             hold_active;
 227#define UNTIL_IOCTL     1
 228#define UNTIL_STOP      2
 229
 230        /* Superblock information */
 231        int                             major_version,
 232                                        minor_version,
 233                                        patch_version;
 234        int                             persistent;
 235        int                             external;       /* metadata is
 236                                                         * managed externally */
 237        char                            metadata_type[17]; /* externally set*/
 238        int                             chunk_sectors;
 239        time_t                          ctime, utime;
 240        int                             level, layout;
 241        char                            clevel[16];
 242        int                             raid_disks;
 243        int                             max_disks;
 244        sector_t                        dev_sectors;    /* used size of
 245                                                         * component devices */
 246        sector_t                        array_sectors; /* exported array size */
 247        int                             external_size; /* size managed
 248                                                        * externally */
 249        __u64                           events;
 250        /* If the last 'event' was simply a clean->dirty transition, and
 251         * we didn't write it to the spares, then it is safe and simple
 252         * to just decrement the event count on a dirty->clean transition.
 253         * So we record that possibility here.
 254         */
 255        int                             can_decrease_events;
 256
 257        char                            uuid[16];
 258
 259        /* If the array is being reshaped, we need to record the
 260         * new shape and an indication of where we are up to.
 261         * This is written to the superblock.
 262         * If reshape_position is MaxSector, then no reshape is happening (yet).
 263         */
 264        sector_t                        reshape_position;
 265        int                             delta_disks, new_level, new_layout;
 266        int                             new_chunk_sectors;
 267        int                             reshape_backwards;
 268
 269        struct md_thread                *thread;        /* management thread */
 270        struct md_thread                *sync_thread;   /* doing resync or reconstruct */
 271
 272        /* 'last_sync_action' is initialized to "none".  It is set when a
 273         * sync operation (i.e "data-check", "requested-resync", "resync",
 274         * "recovery", or "reshape") is started.  It holds this value even
 275         * when the sync thread is "frozen" (interrupted) or "idle" (stopped
 276         * or finished).  It is overwritten when a new sync operation is begun.
 277         */
 278        char                            *last_sync_action;
 279        sector_t                        curr_resync;    /* last block scheduled */
 280        /* As resync requests can complete out of order, we cannot easily track
 281         * how much resync has been completed.  So we occasionally pause until
 282         * everything completes, then set curr_resync_completed to curr_resync.
 283         * As such it may be well behind the real resync mark, but it is a value
 284         * we are certain of.
 285         */
 286        sector_t                        curr_resync_completed;
 287        unsigned long                   resync_mark;    /* a recent timestamp */
 288        sector_t                        resync_mark_cnt;/* blocks written at resync_mark */
 289        sector_t                        curr_mark_cnt; /* blocks scheduled now */
 290
 291        sector_t                        resync_max_sectors; /* may be set by personality */
 292
 293        atomic64_t                      resync_mismatches; /* count of sectors where
 294                                                            * parity/replica mismatch found
 295                                                            */
 296
 297        /* allow user-space to request suspension of IO to regions of the array */
 298        sector_t                        suspend_lo;
 299        sector_t                        suspend_hi;
 300        /* if zero, use the system-wide default */
 301        int                             sync_speed_min;
 302        int                             sync_speed_max;
 303
 304        /* resync even though the same disks are shared among md-devices */
 305        int                             parallel_resync;
 306
 307        int                             ok_start_degraded;
 308        /* recovery/resync flags 
 309         * NEEDED:   we might need to start a resync/recover
 310         * RUNNING:  a thread is running, or about to be started
 311         * SYNC:     actually doing a resync, not a recovery
 312         * RECOVER:  doing recovery, or need to try it.
 313         * INTR:     resync needs to be aborted for some reason
 314         * DONE:     thread is done and is waiting to be reaped
 315         * REQUEST:  user-space has requested a sync (used with SYNC)
 316         * CHECK:    user-space request for check-only, no repair
 317         * RESHAPE:  A reshape is happening
 318         * ERROR:    sync-action interrupted because io-error
 319         *
 320         * If neither SYNC or RESHAPE are set, then it is a recovery.
 321         */
 322#define MD_RECOVERY_RUNNING     0
 323#define MD_RECOVERY_SYNC        1
 324#define MD_RECOVERY_RECOVER     2
 325#define MD_RECOVERY_INTR        3
 326#define MD_RECOVERY_DONE        4
 327#define MD_RECOVERY_NEEDED      5
 328#define MD_RECOVERY_REQUESTED   6
 329#define MD_RECOVERY_CHECK       7
 330#define MD_RECOVERY_RESHAPE     8
 331#define MD_RECOVERY_FROZEN      9
 332#define MD_RECOVERY_ERROR       10
 333
 334        unsigned long                   recovery;
 335        /* If a RAID personality determines that recovery (of a particular
 336         * device) will fail due to a read error on the source device, it
 337         * takes a copy of this number and does not attempt recovery again
 338         * until this number changes.
 339         */
 340        int                             recovery_disabled;
 341
 342        int                             in_sync;        /* know to not need resync */
 343        /* 'open_mutex' avoids races between 'md_open' and 'do_md_stop', so
 344         * that we are never stopping an array while it is open.
 345         * 'reconfig_mutex' protects all other reconfiguration.
 346         * These locks are separate due to conflicting interactions
 347         * with bdev->bd_mutex.
 348         * Lock ordering is:
 349         *  reconfig_mutex -> bd_mutex : e.g. do_md_run -> revalidate_disk
 350         *  bd_mutex -> open_mutex:  e.g. __blkdev_get -> md_open
 351         */
 352        struct mutex                    open_mutex;
 353        struct mutex                    reconfig_mutex;
 354        atomic_t                        active;         /* general refcount */
 355        atomic_t                        openers;        /* number of active opens */
 356
 357        int                             changed;        /* True if we might need to
 358                                                         * reread partition info */
 359        int                             degraded;       /* whether md should consider
 360                                                         * adding a spare
 361                                                         */
 362        int                             merge_check_needed; /* at least one
 363                                                             * member device
 364                                                             * has a
 365                                                             * merge_bvec_fn */
 366
 367        atomic_t                        recovery_active; /* blocks scheduled, but not written */
 368        wait_queue_head_t               recovery_wait;
 369        sector_t                        recovery_cp;
 370        sector_t                        resync_min;     /* user requested sync
 371                                                         * starts here */
 372        sector_t                        resync_max;     /* resync should pause
 373                                                         * when it gets here */
 374
 375        struct sysfs_dirent             *sysfs_state;   /* handle for 'array_state'
 376                                                         * file in sysfs.
 377                                                         */
 378        struct sysfs_dirent             *sysfs_action;  /* handle for 'sync_action' */
 379
 380        struct work_struct del_work;    /* used for delayed sysfs removal */
 381
 382        spinlock_t                      write_lock;
 383        wait_queue_head_t               sb_wait;        /* for waiting on superblock updates */
 384        atomic_t                        pending_writes; /* number of active superblock writes */
 385
 386        unsigned int                    safemode;       /* if set, update "clean" superblock
 387                                                         * when no writes pending.
 388                                                         */ 
 389        unsigned int                    safemode_delay;
 390        struct timer_list               safemode_timer;
 391        atomic_t                        writes_pending; 
 392        struct request_queue            *queue; /* for plugging ... */
 393
 394        struct bitmap                   *bitmap; /* the bitmap for the device */
 395        struct {
 396                struct file             *file; /* the bitmap file */
 397                loff_t                  offset; /* offset from superblock of
 398                                                 * start of bitmap. May be
 399                                                 * negative, but not '0'
 400                                                 * For external metadata, offset
 401                                                 * from start of device. 
 402                                                 */
 403                unsigned long           space; /* space available at this offset */
 404                loff_t                  default_offset; /* this is the offset to use when
 405                                                         * hot-adding a bitmap.  It should
 406                                                         * eventually be settable by sysfs.
 407                                                         */
 408                unsigned long           default_space; /* space available at
 409                                                        * default offset */
 410                struct mutex            mutex;
 411                unsigned long           chunksize;
 412                unsigned long           daemon_sleep; /* how many jiffies between updates? */
 413                unsigned long           max_write_behind; /* write-behind mode */
 414                int                     external;
 415        } bitmap_info;
 416
 417        atomic_t                        max_corr_read_errors; /* max read retries */
 418        struct list_head                all_mddevs;
 419
 420        struct attribute_group          *to_remove;
 421
 422        struct bio_set                  *bio_set;
 423
 424        /* Generic flush handling.
 425         * The last to finish preflush schedules a worker to submit
 426         * the rest of the request (without the REQ_FLUSH flag).
 427         */
 428        struct bio *flush_bio;
 429        atomic_t flush_pending;
 430        struct work_struct flush_work;
 431        struct work_struct event_work;  /* used by dm to report failure event */
 432        void (*sync_super)(struct mddev *mddev, struct md_rdev *rdev);
 433};
 434
 435
 436static inline void rdev_dec_pending(struct md_rdev *rdev, struct mddev *mddev)
 437{
 438        int faulty = test_bit(Faulty, &rdev->flags);
 439        if (atomic_dec_and_test(&rdev->nr_pending) && faulty)
 440                set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
 441}
 442
 443static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors)
 444{
 445        atomic_add(nr_sectors, &bdev->bd_contains->bd_disk->sync_io);
 446}
 447
 448struct md_personality
 449{
 450        char *name;
 451        int level;
 452        struct list_head list;
 453        struct module *owner;
 454        void (*make_request)(struct mddev *mddev, struct bio *bio);
 455        int (*run)(struct mddev *mddev);
 456        int (*stop)(struct mddev *mddev);
 457        void (*status)(struct seq_file *seq, struct mddev *mddev);
 458        /* error_handler must set ->faulty and clear ->in_sync
 459         * if appropriate, and should abort recovery if needed 
 460         */
 461        void (*error_handler)(struct mddev *mddev, struct md_rdev *rdev);
 462        int (*hot_add_disk) (struct mddev *mddev, struct md_rdev *rdev);
 463        int (*hot_remove_disk) (struct mddev *mddev, struct md_rdev *rdev);
 464        int (*spare_active) (struct mddev *mddev);
 465        sector_t (*sync_request)(struct mddev *mddev, sector_t sector_nr, int *skipped, int go_faster);
 466        int (*resize) (struct mddev *mddev, sector_t sectors);
 467        sector_t (*size) (struct mddev *mddev, sector_t sectors, int raid_disks);
 468        int (*check_reshape) (struct mddev *mddev);
 469        int (*start_reshape) (struct mddev *mddev);
 470        void (*finish_reshape) (struct mddev *mddev);
 471        /* quiesce moves between quiescence states
 472         * 0 - fully active
 473         * 1 - no new requests allowed
 474         * others - reserved
 475         */
 476        void (*quiesce) (struct mddev *mddev, int state);
 477        /* takeover is used to transition an array from one
 478         * personality to another.  The new personality must be able
 479         * to handle the data in the current layout.
 480         * e.g. 2drive raid1 -> 2drive raid5
 481         *      ndrive raid5 -> degraded n+1drive raid6 with special layout
 482         * If the takeover succeeds, a new 'private' structure is returned.
 483         * This needs to be installed and then ->run used to activate the
 484         * array.
 485         */
 486        void *(*takeover) (struct mddev *mddev);
 487};
 488
 489
 490struct md_sysfs_entry {
 491        struct attribute attr;
 492        ssize_t (*show)(struct mddev *, char *);
 493        ssize_t (*store)(struct mddev *, const char *, size_t);
 494};
 495extern struct attribute_group md_bitmap_group;
 496
 497static inline struct sysfs_dirent *sysfs_get_dirent_safe(struct sysfs_dirent *sd, char *name)
 498{
 499        if (sd)
 500                return sysfs_get_dirent(sd, NULL, name);
 501        return sd;
 502}
 503static inline void sysfs_notify_dirent_safe(struct sysfs_dirent *sd)
 504{
 505        if (sd)
 506                sysfs_notify_dirent(sd);
 507}
 508
 509static inline char * mdname (struct mddev * mddev)
 510{
 511        return mddev->gendisk ? mddev->gendisk->disk_name : "mdX";
 512}
 513
 514static inline int sysfs_link_rdev(struct mddev *mddev, struct md_rdev *rdev)
 515{
 516        char nm[20];
 517        if (!test_bit(Replacement, &rdev->flags) && mddev->kobj.sd) {
 518                sprintf(nm, "rd%d", rdev->raid_disk);
 519                return sysfs_create_link(&mddev->kobj, &rdev->kobj, nm);
 520        } else
 521                return 0;
 522}
 523
 524static inline void sysfs_unlink_rdev(struct mddev *mddev, struct md_rdev *rdev)
 525{
 526        char nm[20];
 527        if (!test_bit(Replacement, &rdev->flags) && mddev->kobj.sd) {
 528                sprintf(nm, "rd%d", rdev->raid_disk);
 529                sysfs_remove_link(&mddev->kobj, nm);
 530        }
 531}
 532
 533/*
 534 * iterates through some rdev ringlist. It's safe to remove the
 535 * current 'rdev'. Dont touch 'tmp' though.
 536 */
 537#define rdev_for_each_list(rdev, tmp, head)                             \
 538        list_for_each_entry_safe(rdev, tmp, head, same_set)
 539
 540/*
 541 * iterates through the 'same array disks' ringlist
 542 */
 543#define rdev_for_each(rdev, mddev)                              \
 544        list_for_each_entry(rdev, &((mddev)->disks), same_set)
 545
 546#define rdev_for_each_safe(rdev, tmp, mddev)                            \
 547        list_for_each_entry_safe(rdev, tmp, &((mddev)->disks), same_set)
 548
 549#define rdev_for_each_rcu(rdev, mddev)                          \
 550        list_for_each_entry_rcu(rdev, &((mddev)->disks), same_set)
 551
 552struct md_thread {
 553        void                    (*run) (struct md_thread *thread);
 554        struct mddev            *mddev;
 555        wait_queue_head_t       wqueue;
 556        unsigned long           flags;
 557        struct task_struct      *tsk;
 558        unsigned long           timeout;
 559        void                    *private;
 560};
 561
 562#define THREAD_WAKEUP  0
 563
 564static inline void safe_put_page(struct page *p)
 565{
 566        if (p) put_page(p);
 567}
 568
 569extern int register_md_personality(struct md_personality *p);
 570extern int unregister_md_personality(struct md_personality *p);
 571extern struct md_thread *md_register_thread(
 572        void (*run)(struct md_thread *thread),
 573        struct mddev *mddev,
 574        const char *name);
 575extern void md_unregister_thread(struct md_thread **threadp);
 576extern void md_wakeup_thread(struct md_thread *thread);
 577extern void md_check_recovery(struct mddev *mddev);
 578extern void md_reap_sync_thread(struct mddev *mddev);
 579extern void md_write_start(struct mddev *mddev, struct bio *bi);
 580extern void md_write_end(struct mddev *mddev);
 581extern void md_done_sync(struct mddev *mddev, int blocks, int ok);
 582extern void md_error(struct mddev *mddev, struct md_rdev *rdev);
 583extern void md_finish_reshape(struct mddev *mddev);
 584
 585extern int mddev_congested(struct mddev *mddev, int bits);
 586extern void md_flush_request(struct mddev *mddev, struct bio *bio);
 587extern void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
 588                           sector_t sector, int size, struct page *page);
 589extern void md_super_wait(struct mddev *mddev);
 590extern int sync_page_io(struct md_rdev *rdev, sector_t sector, int size, 
 591                        struct page *page, int rw, bool metadata_op);
 592extern void md_do_sync(struct md_thread *thread);
 593extern void md_new_event(struct mddev *mddev);
 594extern int md_allow_write(struct mddev *mddev);
 595extern void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev);
 596extern void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors);
 597extern int md_check_no_bitmap(struct mddev *mddev);
 598extern int md_integrity_register(struct mddev *mddev);
 599extern void md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev);
 600extern int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale);
 601extern void restore_bitmap_write_access(struct file *file);
 602
 603extern void mddev_init(struct mddev *mddev);
 604extern int md_run(struct mddev *mddev);
 605extern void md_stop(struct mddev *mddev);
 606extern void md_stop_writes(struct mddev *mddev);
 607extern int md_rdev_init(struct md_rdev *rdev);
 608extern void md_rdev_clear(struct md_rdev *rdev);
 609
 610extern void mddev_suspend(struct mddev *mddev);
 611extern void mddev_resume(struct mddev *mddev);
 612extern struct bio *bio_clone_mddev(struct bio *bio, gfp_t gfp_mask,
 613                                   struct mddev *mddev);
 614extern struct bio *bio_alloc_mddev(gfp_t gfp_mask, int nr_iovecs,
 615                                   struct mddev *mddev);
 616extern void md_trim_bio(struct bio *bio, int offset, int size);
 617
 618extern void md_unplug(struct blk_plug_cb *cb, bool from_schedule);
 619static inline int mddev_check_plugged(struct mddev *mddev)
 620{
 621        return !!blk_check_plugged(md_unplug, mddev,
 622                                   sizeof(struct blk_plug_cb));
 623}
 624#endif /* _MD_MD_H */
 625
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.