linux/drivers/md/md.c
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   1/*
   2   md.c : Multiple Devices driver for Linux
   3          Copyright (C) 1998, 1999, 2000 Ingo Molnar
   4
   5     completely rewritten, based on the MD driver code from Marc Zyngier
   6
   7   Changes:
   8
   9   - RAID-1/RAID-5 extensions by Miguel de Icaza, Gadi Oxman, Ingo Molnar
  10   - RAID-6 extensions by H. Peter Anvin <hpa@zytor.com>
  11   - boot support for linear and striped mode by Harald Hoyer <HarryH@Royal.Net>
  12   - kerneld support by Boris Tobotras <boris@xtalk.msk.su>
  13   - kmod support by: Cyrus Durgin
  14   - RAID0 bugfixes: Mark Anthony Lisher <markal@iname.com>
  15   - Devfs support by Richard Gooch <rgooch@atnf.csiro.au>
  16
  17   - lots of fixes and improvements to the RAID1/RAID5 and generic
  18     RAID code (such as request based resynchronization):
  19
  20     Neil Brown <neilb@cse.unsw.edu.au>.
  21
  22   - persistent bitmap code
  23     Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.
  24
  25   This program is free software; you can redistribute it and/or modify
  26   it under the terms of the GNU General Public License as published by
  27   the Free Software Foundation; either version 2, or (at your option)
  28   any later version.
  29
  30   You should have received a copy of the GNU General Public License
  31   (for example /usr/src/linux/COPYING); if not, write to the Free
  32   Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  33*/
  34
  35#include <linux/kthread.h>
  36#include <linux/blkdev.h>
  37#include <linux/sysctl.h>
  38#include <linux/seq_file.h>
  39#include <linux/fs.h>
  40#include <linux/poll.h>
  41#include <linux/ctype.h>
  42#include <linux/string.h>
  43#include <linux/hdreg.h>
  44#include <linux/proc_fs.h>
  45#include <linux/random.h>
  46#include <linux/module.h>
  47#include <linux/reboot.h>
  48#include <linux/file.h>
  49#include <linux/compat.h>
  50#include <linux/delay.h>
  51#include <linux/raid/md_p.h>
  52#include <linux/raid/md_u.h>
  53#include <linux/slab.h>
  54#include "md.h"
  55#include "bitmap.h"
  56
  57#ifndef MODULE
  58static void autostart_arrays(int part);
  59#endif
  60
  61/* pers_list is a list of registered personalities protected
  62 * by pers_lock.
  63 * pers_lock does extra service to protect accesses to
  64 * mddev->thread when the mutex cannot be held.
  65 */
  66static LIST_HEAD(pers_list);
  67static DEFINE_SPINLOCK(pers_lock);
  68
  69static void md_print_devices(void);
  70
  71static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
  72static struct workqueue_struct *md_wq;
  73static struct workqueue_struct *md_misc_wq;
  74
  75static int remove_and_add_spares(struct mddev *mddev,
  76                                 struct md_rdev *this);
  77
  78#define MD_BUG(x...) { printk("md: bug in file %s, line %d\n", __FILE__, __LINE__); md_print_devices(); }
  79
  80/*
  81 * Default number of read corrections we'll attempt on an rdev
  82 * before ejecting it from the array. We divide the read error
  83 * count by 2 for every hour elapsed between read errors.
  84 */
  85#define MD_DEFAULT_MAX_CORRECTED_READ_ERRORS 20
  86/*
  87 * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
  88 * is 1000 KB/sec, so the extra system load does not show up that much.
  89 * Increase it if you want to have more _guaranteed_ speed. Note that
  90 * the RAID driver will use the maximum available bandwidth if the IO
  91 * subsystem is idle. There is also an 'absolute maximum' reconstruction
  92 * speed limit - in case reconstruction slows down your system despite
  93 * idle IO detection.
  94 *
  95 * you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
  96 * or /sys/block/mdX/md/sync_speed_{min,max}
  97 */
  98
  99static int sysctl_speed_limit_min = 1000;
 100static int sysctl_speed_limit_max = 200000;
 101static inline int speed_min(struct mddev *mddev)
 102{
 103        return mddev->sync_speed_min ?
 104                mddev->sync_speed_min : sysctl_speed_limit_min;
 105}
 106
 107static inline int speed_max(struct mddev *mddev)
 108{
 109        return mddev->sync_speed_max ?
 110                mddev->sync_speed_max : sysctl_speed_limit_max;
 111}
 112
 113static struct ctl_table_header *raid_table_header;
 114
 115static ctl_table raid_table[] = {
 116        {
 117                .procname       = "speed_limit_min",
 118                .data           = &sysctl_speed_limit_min,
 119                .maxlen         = sizeof(int),
 120                .mode           = S_IRUGO|S_IWUSR,
 121                .proc_handler   = proc_dointvec,
 122        },
 123        {
 124                .procname       = "speed_limit_max",
 125                .data           = &sysctl_speed_limit_max,
 126                .maxlen         = sizeof(int),
 127                .mode           = S_IRUGO|S_IWUSR,
 128                .proc_handler   = proc_dointvec,
 129        },
 130        { }
 131};
 132
 133static ctl_table raid_dir_table[] = {
 134        {
 135                .procname       = "raid",
 136                .maxlen         = 0,
 137                .mode           = S_IRUGO|S_IXUGO,
 138                .child          = raid_table,
 139        },
 140        { }
 141};
 142
 143static ctl_table raid_root_table[] = {
 144        {
 145                .procname       = "dev",
 146                .maxlen         = 0,
 147                .mode           = 0555,
 148                .child          = raid_dir_table,
 149        },
 150        {  }
 151};
 152
 153static const struct block_device_operations md_fops;
 154
 155static int start_readonly;
 156
 157/* bio_clone_mddev
 158 * like bio_clone, but with a local bio set
 159 */
 160
 161struct bio *bio_alloc_mddev(gfp_t gfp_mask, int nr_iovecs,
 162                            struct mddev *mddev)
 163{
 164        struct bio *b;
 165
 166        if (!mddev || !mddev->bio_set)
 167                return bio_alloc(gfp_mask, nr_iovecs);
 168
 169        b = bio_alloc_bioset(gfp_mask, nr_iovecs, mddev->bio_set);
 170        if (!b)
 171                return NULL;
 172        return b;
 173}
 174EXPORT_SYMBOL_GPL(bio_alloc_mddev);
 175
 176struct bio *bio_clone_mddev(struct bio *bio, gfp_t gfp_mask,
 177                            struct mddev *mddev)
 178{
 179        if (!mddev || !mddev->bio_set)
 180                return bio_clone(bio, gfp_mask);
 181
 182        return bio_clone_bioset(bio, gfp_mask, mddev->bio_set);
 183}
 184EXPORT_SYMBOL_GPL(bio_clone_mddev);
 185
 186void md_trim_bio(struct bio *bio, int offset, int size)
 187{
 188        /* 'bio' is a cloned bio which we need to trim to match
 189         * the given offset and size.
 190         * This requires adjusting bi_sector, bi_size, and bi_io_vec
 191         */
 192        int i;
 193        struct bio_vec *bvec;
 194        int sofar = 0;
 195
 196        size <<= 9;
 197        if (offset == 0 && size == bio->bi_size)
 198                return;
 199
 200        clear_bit(BIO_SEG_VALID, &bio->bi_flags);
 201
 202        bio_advance(bio, offset << 9);
 203
 204        bio->bi_size = size;
 205
 206        /* avoid any complications with bi_idx being non-zero*/
 207        if (bio->bi_idx) {
 208                memmove(bio->bi_io_vec, bio->bi_io_vec+bio->bi_idx,
 209                        (bio->bi_vcnt - bio->bi_idx) * sizeof(struct bio_vec));
 210                bio->bi_vcnt -= bio->bi_idx;
 211                bio->bi_idx = 0;
 212        }
 213        /* Make sure vcnt and last bv are not too big */
 214        bio_for_each_segment(bvec, bio, i) {
 215                if (sofar + bvec->bv_len > size)
 216                        bvec->bv_len = size - sofar;
 217                if (bvec->bv_len == 0) {
 218                        bio->bi_vcnt = i;
 219                        break;
 220                }
 221                sofar += bvec->bv_len;
 222        }
 223}
 224EXPORT_SYMBOL_GPL(md_trim_bio);
 225
 226/*
 227 * We have a system wide 'event count' that is incremented
 228 * on any 'interesting' event, and readers of /proc/mdstat
 229 * can use 'poll' or 'select' to find out when the event
 230 * count increases.
 231 *
 232 * Events are:
 233 *  start array, stop array, error, add device, remove device,
 234 *  start build, activate spare
 235 */
 236static DECLARE_WAIT_QUEUE_HEAD(md_event_waiters);
 237static atomic_t md_event_count;
 238void md_new_event(struct mddev *mddev)
 239{
 240        atomic_inc(&md_event_count);
 241        wake_up(&md_event_waiters);
 242}
 243EXPORT_SYMBOL_GPL(md_new_event);
 244
 245/* Alternate version that can be called from interrupts
 246 * when calling sysfs_notify isn't needed.
 247 */
 248static void md_new_event_inintr(struct mddev *mddev)
 249{
 250        atomic_inc(&md_event_count);
 251        wake_up(&md_event_waiters);
 252}
 253
 254/*
 255 * Enables to iterate over all existing md arrays
 256 * all_mddevs_lock protects this list.
 257 */
 258static LIST_HEAD(all_mddevs);
 259static DEFINE_SPINLOCK(all_mddevs_lock);
 260
 261
 262/*
 263 * iterates through all used mddevs in the system.
 264 * We take care to grab the all_mddevs_lock whenever navigating
 265 * the list, and to always hold a refcount when unlocked.
 266 * Any code which breaks out of this loop while own
 267 * a reference to the current mddev and must mddev_put it.
 268 */
 269#define for_each_mddev(_mddev,_tmp)                                     \
 270                                                                        \
 271        for (({ spin_lock(&all_mddevs_lock);                            \
 272                _tmp = all_mddevs.next;                                 \
 273                _mddev = NULL;});                                       \
 274             ({ if (_tmp != &all_mddevs)                                \
 275                        mddev_get(list_entry(_tmp, struct mddev, all_mddevs));\
 276                spin_unlock(&all_mddevs_lock);                          \
 277                if (_mddev) mddev_put(_mddev);                          \
 278                _mddev = list_entry(_tmp, struct mddev, all_mddevs);    \
 279                _tmp != &all_mddevs;});                                 \
 280             ({ spin_lock(&all_mddevs_lock);                            \
 281                _tmp = _tmp->next;})                                    \
 282                )
 283
 284
 285/* Rather than calling directly into the personality make_request function,
 286 * IO requests come here first so that we can check if the device is
 287 * being suspended pending a reconfiguration.
 288 * We hold a refcount over the call to ->make_request.  By the time that
 289 * call has finished, the bio has been linked into some internal structure
 290 * and so is visible to ->quiesce(), so we don't need the refcount any more.
 291 */
 292static void md_make_request(struct request_queue *q, struct bio *bio)
 293{
 294        const int rw = bio_data_dir(bio);
 295        struct mddev *mddev = q->queuedata;
 296        int cpu;
 297        unsigned int sectors;
 298
 299        if (mddev == NULL || mddev->pers == NULL
 300            || !mddev->ready) {
 301                bio_io_error(bio);
 302                return;
 303        }
 304        if (mddev->ro == 1 && unlikely(rw == WRITE)) {
 305                bio_endio(bio, bio_sectors(bio) == 0 ? 0 : -EROFS);
 306                return;
 307        }
 308        smp_rmb(); /* Ensure implications of  'active' are visible */
 309        rcu_read_lock();
 310        if (mddev->suspended) {
 311                DEFINE_WAIT(__wait);
 312                for (;;) {
 313                        prepare_to_wait(&mddev->sb_wait, &__wait,
 314                                        TASK_UNINTERRUPTIBLE);
 315                        if (!mddev->suspended)
 316                                break;
 317                        rcu_read_unlock();
 318                        schedule();
 319                        rcu_read_lock();
 320                }
 321                finish_wait(&mddev->sb_wait, &__wait);
 322        }
 323        atomic_inc(&mddev->active_io);
 324        rcu_read_unlock();
 325
 326        /*
 327         * save the sectors now since our bio can
 328         * go away inside make_request
 329         */
 330        sectors = bio_sectors(bio);
 331        mddev->pers->make_request(mddev, bio);
 332
 333        cpu = part_stat_lock();
 334        part_stat_inc(cpu, &mddev->gendisk->part0, ios[rw]);
 335        part_stat_add(cpu, &mddev->gendisk->part0, sectors[rw], sectors);
 336        part_stat_unlock();
 337
 338        if (atomic_dec_and_test(&mddev->active_io) && mddev->suspended)
 339                wake_up(&mddev->sb_wait);
 340}
 341
 342/* mddev_suspend makes sure no new requests are submitted
 343 * to the device, and that any requests that have been submitted
 344 * are completely handled.
 345 * Once ->stop is called and completes, the module will be completely
 346 * unused.
 347 */
 348void mddev_suspend(struct mddev *mddev)
 349{
 350        BUG_ON(mddev->suspended);
 351        mddev->suspended = 1;
 352        synchronize_rcu();
 353        wait_event(mddev->sb_wait, atomic_read(&mddev->active_io) == 0);
 354        mddev->pers->quiesce(mddev, 1);
 355
 356        del_timer_sync(&mddev->safemode_timer);
 357}
 358EXPORT_SYMBOL_GPL(mddev_suspend);
 359
 360void mddev_resume(struct mddev *mddev)
 361{
 362        mddev->suspended = 0;
 363        wake_up(&mddev->sb_wait);
 364        mddev->pers->quiesce(mddev, 0);
 365
 366        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
 367        md_wakeup_thread(mddev->thread);
 368        md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
 369}
 370EXPORT_SYMBOL_GPL(mddev_resume);
 371
 372int mddev_congested(struct mddev *mddev, int bits)
 373{
 374        return mddev->suspended;
 375}
 376EXPORT_SYMBOL(mddev_congested);
 377
 378/*
 379 * Generic flush handling for md
 380 */
 381
 382static void md_end_flush(struct bio *bio, int err)
 383{
 384        struct md_rdev *rdev = bio->bi_private;
 385        struct mddev *mddev = rdev->mddev;
 386
 387        rdev_dec_pending(rdev, mddev);
 388
 389        if (atomic_dec_and_test(&mddev->flush_pending)) {
 390                /* The pre-request flush has finished */
 391                queue_work(md_wq, &mddev->flush_work);
 392        }
 393        bio_put(bio);
 394}
 395
 396static void md_submit_flush_data(struct work_struct *ws);
 397
 398static void submit_flushes(struct work_struct *ws)
 399{
 400        struct mddev *mddev = container_of(ws, struct mddev, flush_work);
 401        struct md_rdev *rdev;
 402
 403        INIT_WORK(&mddev->flush_work, md_submit_flush_data);
 404        atomic_set(&mddev->flush_pending, 1);
 405        rcu_read_lock();
 406        rdev_for_each_rcu(rdev, mddev)
 407                if (rdev->raid_disk >= 0 &&
 408                    !test_bit(Faulty, &rdev->flags)) {
 409                        /* Take two references, one is dropped
 410                         * when request finishes, one after
 411                         * we reclaim rcu_read_lock
 412                         */
 413                        struct bio *bi;
 414                        atomic_inc(&rdev->nr_pending);
 415                        atomic_inc(&rdev->nr_pending);
 416                        rcu_read_unlock();
 417                        bi = bio_alloc_mddev(GFP_NOIO, 0, mddev);
 418                        bi->bi_end_io = md_end_flush;
 419                        bi->bi_private = rdev;
 420                        bi->bi_bdev = rdev->bdev;
 421                        atomic_inc(&mddev->flush_pending);
 422                        submit_bio(WRITE_FLUSH, bi);
 423                        rcu_read_lock();
 424                        rdev_dec_pending(rdev, mddev);
 425                }
 426        rcu_read_unlock();
 427        if (atomic_dec_and_test(&mddev->flush_pending))
 428                queue_work(md_wq, &mddev->flush_work);
 429}
 430
 431static void md_submit_flush_data(struct work_struct *ws)
 432{
 433        struct mddev *mddev = container_of(ws, struct mddev, flush_work);
 434        struct bio *bio = mddev->flush_bio;
 435
 436        if (bio->bi_size == 0)
 437                /* an empty barrier - all done */
 438                bio_endio(bio, 0);
 439        else {
 440                bio->bi_rw &= ~REQ_FLUSH;
 441                mddev->pers->make_request(mddev, bio);
 442        }
 443
 444        mddev->flush_bio = NULL;
 445        wake_up(&mddev->sb_wait);
 446}
 447
 448void md_flush_request(struct mddev *mddev, struct bio *bio)
 449{
 450        spin_lock_irq(&mddev->write_lock);
 451        wait_event_lock_irq(mddev->sb_wait,
 452                            !mddev->flush_bio,
 453                            mddev->write_lock);
 454        mddev->flush_bio = bio;
 455        spin_unlock_irq(&mddev->write_lock);
 456
 457        INIT_WORK(&mddev->flush_work, submit_flushes);
 458        queue_work(md_wq, &mddev->flush_work);
 459}
 460EXPORT_SYMBOL(md_flush_request);
 461
 462void md_unplug(struct blk_plug_cb *cb, bool from_schedule)
 463{
 464        struct mddev *mddev = cb->data;
 465        md_wakeup_thread(mddev->thread);
 466        kfree(cb);
 467}
 468EXPORT_SYMBOL(md_unplug);
 469
 470static inline struct mddev *mddev_get(struct mddev *mddev)
 471{
 472        atomic_inc(&mddev->active);
 473        return mddev;
 474}
 475
 476static void mddev_delayed_delete(struct work_struct *ws);
 477
 478static void mddev_put(struct mddev *mddev)
 479{
 480        struct bio_set *bs = NULL;
 481
 482        if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
 483                return;
 484        if (!mddev->raid_disks && list_empty(&mddev->disks) &&
 485            mddev->ctime == 0 && !mddev->hold_active) {
 486                /* Array is not configured at all, and not held active,
 487                 * so destroy it */
 488                list_del_init(&mddev->all_mddevs);
 489                bs = mddev->bio_set;
 490                mddev->bio_set = NULL;
 491                if (mddev->gendisk) {
 492                        /* We did a probe so need to clean up.  Call
 493                         * queue_work inside the spinlock so that
 494                         * flush_workqueue() after mddev_find will
 495                         * succeed in waiting for the work to be done.
 496                         */
 497                        INIT_WORK(&mddev->del_work, mddev_delayed_delete);
 498                        queue_work(md_misc_wq, &mddev->del_work);
 499                } else
 500                        kfree(mddev);
 501        }
 502        spin_unlock(&all_mddevs_lock);
 503        if (bs)
 504                bioset_free(bs);
 505}
 506
 507void mddev_init(struct mddev *mddev)
 508{
 509        mutex_init(&mddev->open_mutex);
 510        mutex_init(&mddev->reconfig_mutex);
 511        mutex_init(&mddev->bitmap_info.mutex);
 512        INIT_LIST_HEAD(&mddev->disks);
 513        INIT_LIST_HEAD(&mddev->all_mddevs);
 514        init_timer(&mddev->safemode_timer);
 515        atomic_set(&mddev->active, 1);
 516        atomic_set(&mddev->openers, 0);
 517        atomic_set(&mddev->active_io, 0);
 518        spin_lock_init(&mddev->write_lock);
 519        atomic_set(&mddev->flush_pending, 0);
 520        init_waitqueue_head(&mddev->sb_wait);
 521        init_waitqueue_head(&mddev->recovery_wait);
 522        mddev->reshape_position = MaxSector;
 523        mddev->reshape_backwards = 0;
 524        mddev->resync_min = 0;
 525        mddev->resync_max = MaxSector;
 526        mddev->level = LEVEL_NONE;
 527}
 528EXPORT_SYMBOL_GPL(mddev_init);
 529
 530static struct mddev * mddev_find(dev_t unit)
 531{
 532        struct mddev *mddev, *new = NULL;
 533
 534        if (unit && MAJOR(unit) != MD_MAJOR)
 535                unit &= ~((1<<MdpMinorShift)-1);
 536
 537 retry:
 538        spin_lock(&all_mddevs_lock);
 539
 540        if (unit) {
 541                list_for_each_entry(mddev, &all_mddevs, all_mddevs)
 542                        if (mddev->unit == unit) {
 543                                mddev_get(mddev);
 544                                spin_unlock(&all_mddevs_lock);
 545                                kfree(new);
 546                                return mddev;
 547                        }
 548
 549                if (new) {
 550                        list_add(&new->all_mddevs, &all_mddevs);
 551                        spin_unlock(&all_mddevs_lock);
 552                        new->hold_active = UNTIL_IOCTL;
 553                        return new;
 554                }
 555        } else if (new) {
 556                /* find an unused unit number */
 557                static int next_minor = 512;
 558                int start = next_minor;
 559                int is_free = 0;
 560                int dev = 0;
 561                while (!is_free) {
 562                        dev = MKDEV(MD_MAJOR, next_minor);
 563                        next_minor++;
 564                        if (next_minor > MINORMASK)
 565                                next_minor = 0;
 566                        if (next_minor == start) {
 567                                /* Oh dear, all in use. */
 568                                spin_unlock(&all_mddevs_lock);
 569                                kfree(new);
 570                                return NULL;
 571                        }
 572                                
 573                        is_free = 1;
 574                        list_for_each_entry(mddev, &all_mddevs, all_mddevs)
 575                                if (mddev->unit == dev) {
 576                                        is_free = 0;
 577                                        break;
 578                                }
 579                }
 580                new->unit = dev;
 581                new->md_minor = MINOR(dev);
 582                new->hold_active = UNTIL_STOP;
 583                list_add(&new->all_mddevs, &all_mddevs);
 584                spin_unlock(&all_mddevs_lock);
 585                return new;
 586        }
 587        spin_unlock(&all_mddevs_lock);
 588
 589        new = kzalloc(sizeof(*new), GFP_KERNEL);
 590        if (!new)
 591                return NULL;
 592
 593        new->unit = unit;
 594        if (MAJOR(unit) == MD_MAJOR)
 595                new->md_minor = MINOR(unit);
 596        else
 597                new->md_minor = MINOR(unit) >> MdpMinorShift;
 598
 599        mddev_init(new);
 600
 601        goto retry;
 602}
 603
 604static inline int mddev_lock(struct mddev * mddev)
 605{
 606        return mutex_lock_interruptible(&mddev->reconfig_mutex);
 607}
 608
 609static inline int mddev_is_locked(struct mddev *mddev)
 610{
 611        return mutex_is_locked(&mddev->reconfig_mutex);
 612}
 613
 614static inline int mddev_trylock(struct mddev * mddev)
 615{
 616        return mutex_trylock(&mddev->reconfig_mutex);
 617}
 618
 619static struct attribute_group md_redundancy_group;
 620
 621static void mddev_unlock(struct mddev * mddev)
 622{
 623        if (mddev->to_remove) {
 624                /* These cannot be removed under reconfig_mutex as
 625                 * an access to the files will try to take reconfig_mutex
 626                 * while holding the file unremovable, which leads to
 627                 * a deadlock.
 628                 * So hold set sysfs_active while the remove in happeing,
 629                 * and anything else which might set ->to_remove or my
 630                 * otherwise change the sysfs namespace will fail with
 631                 * -EBUSY if sysfs_active is still set.
 632                 * We set sysfs_active under reconfig_mutex and elsewhere
 633                 * test it under the same mutex to ensure its correct value
 634                 * is seen.
 635                 */
 636                struct attribute_group *to_remove = mddev->to_remove;
 637                mddev->to_remove = NULL;
 638                mddev->sysfs_active = 1;
 639                mutex_unlock(&mddev->reconfig_mutex);
 640
 641                if (mddev->kobj.sd) {
 642                        if (to_remove != &md_redundancy_group)
 643                                sysfs_remove_group(&mddev->kobj, to_remove);
 644                        if (mddev->pers == NULL ||
 645                            mddev->pers->sync_request == NULL) {
 646                                sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
 647                                if (mddev->sysfs_action)
 648                                        sysfs_put(mddev->sysfs_action);
 649                                mddev->sysfs_action = NULL;
 650                        }
 651                }
 652                mddev->sysfs_active = 0;
 653        } else
 654                mutex_unlock(&mddev->reconfig_mutex);
 655
 656        /* As we've dropped the mutex we need a spinlock to
 657         * make sure the thread doesn't disappear
 658         */
 659        spin_lock(&pers_lock);
 660        md_wakeup_thread(mddev->thread);
 661        spin_unlock(&pers_lock);
 662}
 663
 664static struct md_rdev * find_rdev_nr(struct mddev *mddev, int nr)
 665{
 666        struct md_rdev *rdev;
 667
 668        rdev_for_each(rdev, mddev)
 669                if (rdev->desc_nr == nr)
 670                        return rdev;
 671
 672        return NULL;
 673}
 674
 675static struct md_rdev *find_rdev_nr_rcu(struct mddev *mddev, int nr)
 676{
 677        struct md_rdev *rdev;
 678
 679        rdev_for_each_rcu(rdev, mddev)
 680                if (rdev->desc_nr == nr)
 681                        return rdev;
 682
 683        return NULL;
 684}
 685
 686static struct md_rdev *find_rdev(struct mddev *mddev, dev_t dev)
 687{
 688        struct md_rdev *rdev;
 689
 690        rdev_for_each(rdev, mddev)
 691                if (rdev->bdev->bd_dev == dev)
 692                        return rdev;
 693
 694        return NULL;
 695}
 696
 697static struct md_rdev *find_rdev_rcu(struct mddev *mddev, dev_t dev)
 698{
 699        struct md_rdev *rdev;
 700
 701        rdev_for_each_rcu(rdev, mddev)
 702                if (rdev->bdev->bd_dev == dev)
 703                        return rdev;
 704
 705        return NULL;
 706}
 707
 708static struct md_personality *find_pers(int level, char *clevel)
 709{
 710        struct md_personality *pers;
 711        list_for_each_entry(pers, &pers_list, list) {
 712                if (level != LEVEL_NONE && pers->level == level)
 713                        return pers;
 714                if (strcmp(pers->name, clevel)==0)
 715                        return pers;
 716        }
 717        return NULL;
 718}
 719
 720/* return the offset of the super block in 512byte sectors */
 721static inline sector_t calc_dev_sboffset(struct md_rdev *rdev)
 722{
 723        sector_t num_sectors = i_size_read(rdev->bdev->bd_inode) / 512;
 724        return MD_NEW_SIZE_SECTORS(num_sectors);
 725}
 726
 727static int alloc_disk_sb(struct md_rdev * rdev)
 728{
 729        if (rdev->sb_page)
 730                MD_BUG();
 731
 732        rdev->sb_page = alloc_page(GFP_KERNEL);
 733        if (!rdev->sb_page) {
 734                printk(KERN_ALERT "md: out of memory.\n");
 735                return -ENOMEM;
 736        }
 737
 738        return 0;
 739}
 740
 741void md_rdev_clear(struct md_rdev *rdev)
 742{
 743        if (rdev->sb_page) {
 744                put_page(rdev->sb_page);
 745                rdev->sb_loaded = 0;
 746                rdev->sb_page = NULL;
 747                rdev->sb_start = 0;
 748                rdev->sectors = 0;
 749        }
 750        if (rdev->bb_page) {
 751                put_page(rdev->bb_page);
 752                rdev->bb_page = NULL;
 753        }
 754        kfree(rdev->badblocks.page);
 755        rdev->badblocks.page = NULL;
 756}
 757EXPORT_SYMBOL_GPL(md_rdev_clear);
 758
 759static void super_written(struct bio *bio, int error)
 760{
 761        struct md_rdev *rdev = bio->bi_private;
 762        struct mddev *mddev = rdev->mddev;
 763
 764        if (error || !test_bit(BIO_UPTODATE, &bio->bi_flags)) {
 765                printk("md: super_written gets error=%d, uptodate=%d\n",
 766                       error, test_bit(BIO_UPTODATE, &bio->bi_flags));
 767                WARN_ON(test_bit(BIO_UPTODATE, &bio->bi_flags));
 768                md_error(mddev, rdev);
 769        }
 770
 771        if (atomic_dec_and_test(&mddev->pending_writes))
 772                wake_up(&mddev->sb_wait);
 773        bio_put(bio);
 774}
 775
 776void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
 777                   sector_t sector, int size, struct page *page)
 778{
 779        /* write first size bytes of page to sector of rdev
 780         * Increment mddev->pending_writes before returning
 781         * and decrement it on completion, waking up sb_wait
 782         * if zero is reached.
 783         * If an error occurred, call md_error
 784         */
 785        struct bio *bio = bio_alloc_mddev(GFP_NOIO, 1, mddev);
 786
 787        bio->bi_bdev = rdev->meta_bdev ? rdev->meta_bdev : rdev->bdev;
 788        bio->bi_sector = sector;
 789        bio_add_page(bio, page, size, 0);
 790        bio->bi_private = rdev;
 791        bio->bi_end_io = super_written;
 792
 793        atomic_inc(&mddev->pending_writes);
 794        submit_bio(WRITE_FLUSH_FUA, bio);
 795}
 796
 797void md_super_wait(struct mddev *mddev)
 798{
 799        /* wait for all superblock writes that were scheduled to complete */
 800        DEFINE_WAIT(wq);
 801        for(;;) {
 802                prepare_to_wait(&mddev->sb_wait, &wq, TASK_UNINTERRUPTIBLE);
 803                if (atomic_read(&mddev->pending_writes)==0)
 804                        break;
 805                schedule();
 806        }
 807        finish_wait(&mddev->sb_wait, &wq);
 808}
 809
 810static void bi_complete(struct bio *bio, int error)
 811{
 812        complete((struct completion*)bio->bi_private);
 813}
 814
 815int sync_page_io(struct md_rdev *rdev, sector_t sector, int size,
 816                 struct page *page, int rw, bool metadata_op)
 817{
 818        struct bio *bio = bio_alloc_mddev(GFP_NOIO, 1, rdev->mddev);
 819        struct completion event;
 820        int ret;
 821
 822        rw |= REQ_SYNC;
 823
 824        bio->bi_bdev = (metadata_op && rdev->meta_bdev) ?
 825                rdev->meta_bdev : rdev->bdev;
 826        if (metadata_op)
 827                bio->bi_sector = sector + rdev->sb_start;
 828        else if (rdev->mddev->reshape_position != MaxSector &&
 829                 (rdev->mddev->reshape_backwards ==
 830                  (sector >= rdev->mddev->reshape_position)))
 831                bio->bi_sector = sector + rdev->new_data_offset;
 832        else
 833                bio->bi_sector = sector + rdev->data_offset;
 834        bio_add_page(bio, page, size, 0);
 835        init_completion(&event);
 836        bio->bi_private = &event;
 837        bio->bi_end_io = bi_complete;
 838        submit_bio(rw, bio);
 839        wait_for_completion(&event);
 840
 841        ret = test_bit(BIO_UPTODATE, &bio->bi_flags);
 842        bio_put(bio);
 843        return ret;
 844}
 845EXPORT_SYMBOL_GPL(sync_page_io);
 846
 847static int read_disk_sb(struct md_rdev * rdev, int size)
 848{
 849        char b[BDEVNAME_SIZE];
 850        if (!rdev->sb_page) {
 851                MD_BUG();
 852                return -EINVAL;
 853        }
 854        if (rdev->sb_loaded)
 855                return 0;
 856
 857
 858        if (!sync_page_io(rdev, 0, size, rdev->sb_page, READ, true))
 859                goto fail;
 860        rdev->sb_loaded = 1;
 861        return 0;
 862
 863fail:
 864        printk(KERN_WARNING "md: disabled device %s, could not read superblock.\n",
 865                bdevname(rdev->bdev,b));
 866        return -EINVAL;
 867}
 868
 869static int uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 870{
 871        return  sb1->set_uuid0 == sb2->set_uuid0 &&
 872                sb1->set_uuid1 == sb2->set_uuid1 &&
 873                sb1->set_uuid2 == sb2->set_uuid2 &&
 874                sb1->set_uuid3 == sb2->set_uuid3;
 875}
 876
 877static int sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 878{
 879        int ret;
 880        mdp_super_t *tmp1, *tmp2;
 881
 882        tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
 883        tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
 884
 885        if (!tmp1 || !tmp2) {
 886                ret = 0;
 887                printk(KERN_INFO "md.c sb_equal(): failed to allocate memory!\n");
 888                goto abort;
 889        }
 890
 891        *tmp1 = *sb1;
 892        *tmp2 = *sb2;
 893
 894        /*
 895         * nr_disks is not constant
 896         */
 897        tmp1->nr_disks = 0;
 898        tmp2->nr_disks = 0;
 899
 900        ret = (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4) == 0);
 901abort:
 902        kfree(tmp1);
 903        kfree(tmp2);
 904        return ret;
 905}
 906
 907
 908static u32 md_csum_fold(u32 csum)
 909{
 910        csum = (csum & 0xffff) + (csum >> 16);
 911        return (csum & 0xffff) + (csum >> 16);
 912}
 913
 914static unsigned int calc_sb_csum(mdp_super_t * sb)
 915{
 916        u64 newcsum = 0;
 917        u32 *sb32 = (u32*)sb;
 918        int i;
 919        unsigned int disk_csum, csum;
 920
 921        disk_csum = sb->sb_csum;
 922        sb->sb_csum = 0;
 923
 924        for (i = 0; i < MD_SB_BYTES/4 ; i++)
 925                newcsum += sb32[i];
 926        csum = (newcsum & 0xffffffff) + (newcsum>>32);
 927
 928
 929#ifdef CONFIG_ALPHA
 930        /* This used to use csum_partial, which was wrong for several
 931         * reasons including that different results are returned on
 932         * different architectures.  It isn't critical that we get exactly
 933         * the same return value as before (we always csum_fold before
 934         * testing, and that removes any differences).  However as we
 935         * know that csum_partial always returned a 16bit value on
 936         * alphas, do a fold to maximise conformity to previous behaviour.
 937         */
 938        sb->sb_csum = md_csum_fold(disk_csum);
 939#else
 940        sb->sb_csum = disk_csum;
 941#endif
 942        return csum;
 943}
 944
 945
 946/*
 947 * Handle superblock details.
 948 * We want to be able to handle multiple superblock formats
 949 * so we have a common interface to them all, and an array of
 950 * different handlers.
 951 * We rely on user-space to write the initial superblock, and support
 952 * reading and updating of superblocks.
 953 * Interface methods are:
 954 *   int load_super(struct md_rdev *dev, struct md_rdev *refdev, int minor_version)
 955 *      loads and validates a superblock on dev.
 956 *      if refdev != NULL, compare superblocks on both devices
 957 *    Return:
 958 *      0 - dev has a superblock that is compatible with refdev
 959 *      1 - dev has a superblock that is compatible and newer than refdev
 960 *          so dev should be used as the refdev in future
 961 *     -EINVAL superblock incompatible or invalid
 962 *     -othererror e.g. -EIO
 963 *
 964 *   int validate_super(struct mddev *mddev, struct md_rdev *dev)
 965 *      Verify that dev is acceptable into mddev.
 966 *       The first time, mddev->raid_disks will be 0, and data from
 967 *       dev should be merged in.  Subsequent calls check that dev
 968 *       is new enough.  Return 0 or -EINVAL
 969 *
 970 *   void sync_super(struct mddev *mddev, struct md_rdev *dev)
 971 *     Update the superblock for rdev with data in mddev
 972 *     This does not write to disc.
 973 *
 974 */
 975
 976struct super_type  {
 977        char                *name;
 978        struct module       *owner;
 979        int                 (*load_super)(struct md_rdev *rdev,
 980                                          struct md_rdev *refdev,
 981                                          int minor_version);
 982        int                 (*validate_super)(struct mddev *mddev,
 983                                              struct md_rdev *rdev);
 984        void                (*sync_super)(struct mddev *mddev,
 985                                          struct md_rdev *rdev);
 986        unsigned long long  (*rdev_size_change)(struct md_rdev *rdev,
 987                                                sector_t num_sectors);
 988        int                 (*allow_new_offset)(struct md_rdev *rdev,
 989                                                unsigned long long new_offset);
 990};
 991
 992/*
 993 * Check that the given mddev has no bitmap.
 994 *
 995 * This function is called from the run method of all personalities that do not
 996 * support bitmaps. It prints an error message and returns non-zero if mddev
 997 * has a bitmap. Otherwise, it returns 0.
 998 *
 999 */
1000int md_check_no_bitmap(struct mddev *mddev)
1001{
1002        if (!mddev->bitmap_info.file && !mddev->bitmap_info.offset)
1003                return 0;
1004        printk(KERN_ERR "%s: bitmaps are not supported for %s\n",
1005                mdname(mddev), mddev->pers->name);
1006        return 1;
1007}
1008EXPORT_SYMBOL(md_check_no_bitmap);
1009
1010/*
1011 * load_super for 0.90.0 
1012 */
1013static int super_90_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor_version)
1014{
1015        char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1016        mdp_super_t *sb;
1017        int ret;
1018
1019        /*
1020         * Calculate the position of the superblock (512byte sectors),
1021         * it's at the end of the disk.
1022         *
1023         * It also happens to be a multiple of 4Kb.
1024         */
1025        rdev->sb_start = calc_dev_sboffset(rdev);
1026
1027        ret = read_disk_sb(rdev, MD_SB_BYTES);
1028        if (ret) return ret;
1029
1030        ret = -EINVAL;
1031
1032        bdevname(rdev->bdev, b);
1033        sb = page_address(rdev->sb_page);
1034
1035        if (sb->md_magic != MD_SB_MAGIC) {
1036                printk(KERN_ERR "md: invalid raid superblock magic on %s\n",
1037                       b);
1038                goto abort;
1039        }
1040
1041        if (sb->major_version != 0 ||
1042            sb->minor_version < 90 ||
1043            sb->minor_version > 91) {
1044                printk(KERN_WARNING "Bad version number %d.%d on %s\n",
1045                        sb->major_version, sb->minor_version,
1046                        b);
1047                goto abort;
1048        }
1049
1050        if (sb->raid_disks <= 0)
1051                goto abort;
1052
1053        if (md_csum_fold(calc_sb_csum(sb)) != md_csum_fold(sb->sb_csum)) {
1054                printk(KERN_WARNING "md: invalid superblock checksum on %s\n",
1055                        b);
1056                goto abort;
1057        }
1058
1059        rdev->preferred_minor = sb->md_minor;
1060        rdev->data_offset = 0;
1061        rdev->new_data_offset = 0;
1062        rdev->sb_size = MD_SB_BYTES;
1063        rdev->badblocks.shift = -1;
1064
1065        if (sb->level == LEVEL_MULTIPATH)
1066                rdev->desc_nr = -1;
1067        else
1068                rdev->desc_nr = sb->this_disk.number;
1069
1070        if (!refdev) {
1071                ret = 1;
1072        } else {
1073                __u64 ev1, ev2;
1074                mdp_super_t *refsb = page_address(refdev->sb_page);
1075                if (!uuid_equal(refsb, sb)) {
1076                        printk(KERN_WARNING "md: %s has different UUID to %s\n",
1077                                b, bdevname(refdev->bdev,b2));
1078                        goto abort;
1079                }
1080                if (!sb_equal(refsb, sb)) {
1081                        printk(KERN_WARNING "md: %s has same UUID"
1082                               " but different superblock to %s\n",
1083                               b, bdevname(refdev->bdev, b2));
1084                        goto abort;
1085                }
1086                ev1 = md_event(sb);
1087                ev2 = md_event(refsb);
1088                if (ev1 > ev2)
1089                        ret = 1;
1090                else 
1091                        ret = 0;
1092        }
1093        rdev->sectors = rdev->sb_start;
1094        /* Limit to 4TB as metadata cannot record more than that.
1095         * (not needed for Linear and RAID0 as metadata doesn't
1096         * record this size)
1097         */
1098        if (rdev->sectors >= (2ULL << 32) && sb->level >= 1)
1099                rdev->sectors = (2ULL << 32) - 2;
1100
1101        if (rdev->sectors < ((sector_t)sb->size) * 2 && sb->level >= 1)
1102                /* "this cannot possibly happen" ... */
1103                ret = -EINVAL;
1104
1105 abort:
1106        return ret;
1107}
1108
1109/*
1110 * validate_super for 0.90.0
1111 */
1112static int super_90_validate(struct mddev *mddev, struct md_rdev *rdev)
1113{
1114        mdp_disk_t *desc;
1115        mdp_super_t *sb = page_address(rdev->sb_page);
1116        __u64 ev1 = md_event(sb);
1117
1118        rdev->raid_disk = -1;
1119        clear_bit(Faulty, &rdev->flags);
1120        clear_bit(In_sync, &rdev->flags);
1121        clear_bit(WriteMostly, &rdev->flags);
1122
1123        if (mddev->raid_disks == 0) {
1124                mddev->major_version = 0;
1125                mddev->minor_version = sb->minor_version;
1126                mddev->patch_version = sb->patch_version;
1127                mddev->external = 0;
1128                mddev->chunk_sectors = sb->chunk_size >> 9;
1129                mddev->ctime = sb->ctime;
1130                mddev->utime = sb->utime;
1131                mddev->level = sb->level;
1132                mddev->clevel[0] = 0;
1133                mddev->layout = sb->layout;
1134                mddev->raid_disks = sb->raid_disks;
1135                mddev->dev_sectors = ((sector_t)sb->size) * 2;
1136                mddev->events = ev1;
1137                mddev->bitmap_info.offset = 0;
1138                mddev->bitmap_info.space = 0;
1139                /* bitmap can use 60 K after the 4K superblocks */
1140                mddev->bitmap_info.default_offset = MD_SB_BYTES >> 9;
1141                mddev->bitmap_info.default_space = 64*2 - (MD_SB_BYTES >> 9);
1142                mddev->reshape_backwards = 0;
1143
1144                if (mddev->minor_version >= 91) {
1145                        mddev->reshape_position = sb->reshape_position;
1146                        mddev->delta_disks = sb->delta_disks;
1147                        mddev->new_level = sb->new_level;
1148                        mddev->new_layout = sb->new_layout;
1149                        mddev->new_chunk_sectors = sb->new_chunk >> 9;
1150                        if (mddev->delta_disks < 0)
1151                                mddev->reshape_backwards = 1;
1152                } else {
1153                        mddev->reshape_position = MaxSector;
1154                        mddev->delta_disks = 0;
1155                        mddev->new_level = mddev->level;
1156                        mddev->new_layout = mddev->layout;
1157                        mddev->new_chunk_sectors = mddev->chunk_sectors;
1158                }
1159
1160                if (sb->state & (1<<MD_SB_CLEAN))
1161                        mddev->recovery_cp = MaxSector;
1162                else {
1163                        if (sb->events_hi == sb->cp_events_hi && 
1164                                sb->events_lo == sb->cp_events_lo) {
1165                                mddev->recovery_cp = sb->recovery_cp;
1166                        } else
1167                                mddev->recovery_cp = 0;
1168                }
1169
1170                memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
1171                memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
1172                memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
1173                memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
1174
1175                mddev->max_disks = MD_SB_DISKS;
1176
1177                if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
1178                    mddev->bitmap_info.file == NULL) {
1179                        mddev->bitmap_info.offset =
1180                                mddev->bitmap_info.default_offset;
1181                        mddev->bitmap_info.space =
1182                                mddev->bitmap_info.space;
1183                }
1184
1185        } else if (mddev->pers == NULL) {
1186                /* Insist on good event counter while assembling, except
1187                 * for spares (which don't need an event count) */
1188                ++ev1;
1189                if (sb->disks[rdev->desc_nr].state & (
1190                            (1<<MD_DISK_SYNC) | (1 << MD_DISK_ACTIVE)))
1191                        if (ev1 < mddev->events) 
1192                                return -EINVAL;
1193        } else if (mddev->bitmap) {
1194                /* if adding to array with a bitmap, then we can accept an
1195                 * older device ... but not too old.
1196                 */
1197                if (ev1 < mddev->bitmap->events_cleared)
1198                        return 0;
1199        } else {
1200                if (ev1 < mddev->events)
1201                        /* just a hot-add of a new device, leave raid_disk at -1 */
1202                        return 0;
1203        }
1204
1205        if (mddev->level != LEVEL_MULTIPATH) {
1206                desc = sb->disks + rdev->desc_nr;
1207
1208                if (desc->state & (1<<MD_DISK_FAULTY))
1209                        set_bit(Faulty, &rdev->flags);
1210                else if (desc->state & (1<<MD_DISK_SYNC) /* &&
1211                            desc->raid_disk < mddev->raid_disks */) {
1212                        set_bit(In_sync, &rdev->flags);
1213                        rdev->raid_disk = desc->raid_disk;
1214                } else if (desc->state & (1<<MD_DISK_ACTIVE)) {
1215                        /* active but not in sync implies recovery up to
1216                         * reshape position.  We don't know exactly where
1217                         * that is, so set to zero for now */
1218                        if (mddev->minor_version >= 91) {
1219                                rdev->recovery_offset = 0;
1220                                rdev->raid_disk = desc->raid_disk;
1221                        }
1222                }
1223                if (desc->state & (1<<MD_DISK_WRITEMOSTLY))
1224                        set_bit(WriteMostly, &rdev->flags);
1225        } else /* MULTIPATH are always insync */
1226                set_bit(In_sync, &rdev->flags);
1227        return 0;
1228}
1229
1230/*
1231 * sync_super for 0.90.0
1232 */
1233static void super_90_sync(struct mddev *mddev, struct md_rdev *rdev)
1234{
1235        mdp_super_t *sb;
1236        struct md_rdev *rdev2;
1237        int next_spare = mddev->raid_disks;
1238
1239
1240        /* make rdev->sb match mddev data..
1241         *
1242         * 1/ zero out disks
1243         * 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
1244         * 3/ any empty disks < next_spare become removed
1245         *
1246         * disks[0] gets initialised to REMOVED because
1247         * we cannot be sure from other fields if it has
1248         * been initialised or not.
1249         */
1250        int i;
1251        int active=0, working=0,failed=0,spare=0,nr_disks=0;
1252
1253        rdev->sb_size = MD_SB_BYTES;
1254
1255        sb = page_address(rdev->sb_page);
1256
1257        memset(sb, 0, sizeof(*sb));
1258
1259        sb->md_magic = MD_SB_MAGIC;
1260        sb->major_version = mddev->major_version;
1261        sb->patch_version = mddev->patch_version;
1262        sb->gvalid_words  = 0; /* ignored */
1263        memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
1264        memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
1265        memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
1266        memcpy(&sb->set_uuid3, mddev->uuid+12,4);
1267
1268        sb->ctime = mddev->ctime;
1269        sb->level = mddev->level;
1270        sb->size = mddev->dev_sectors / 2;
1271        sb->raid_disks = mddev->raid_disks;
1272        sb->md_minor = mddev->md_minor;
1273        sb->not_persistent = 0;
1274        sb->utime = mddev->utime;
1275        sb->state = 0;
1276        sb->events_hi = (mddev->events>>32);
1277        sb->events_lo = (u32)mddev->events;
1278
1279        if (mddev->reshape_position == MaxSector)
1280                sb->minor_version = 90;
1281        else {
1282                sb->minor_version = 91;
1283                sb->reshape_position = mddev->reshape_position;
1284                sb->new_level = mddev->new_level;
1285                sb->delta_disks = mddev->delta_disks;
1286                sb->new_layout = mddev->new_layout;
1287                sb->new_chunk = mddev->new_chunk_sectors << 9;
1288        }
1289        mddev->minor_version = sb->minor_version;
1290        if (mddev->in_sync)
1291        {
1292                sb->recovery_cp = mddev->recovery_cp;
1293                sb->cp_events_hi = (mddev->events>>32);
1294                sb->cp_events_lo = (u32)mddev->events;
1295                if (mddev->recovery_cp == MaxSector)
1296                        sb->state = (1<< MD_SB_CLEAN);
1297        } else
1298                sb->recovery_cp = 0;
1299
1300        sb->layout = mddev->layout;
1301        sb->chunk_size = mddev->chunk_sectors << 9;
1302
1303        if (mddev->bitmap && mddev->bitmap_info.file == NULL)
1304                sb->state |= (1<<MD_SB_BITMAP_PRESENT);
1305
1306        sb->disks[0].state = (1<<MD_DISK_REMOVED);
1307        rdev_for_each(rdev2, mddev) {
1308                mdp_disk_t *d;
1309                int desc_nr;
1310                int is_active = test_bit(In_sync, &rdev2->flags);
1311
1312                if (rdev2->raid_disk >= 0 &&
1313                    sb->minor_version >= 91)
1314                        /* we have nowhere to store the recovery_offset,
1315                         * but if it is not below the reshape_position,
1316                         * we can piggy-back on that.
1317                         */
1318                        is_active = 1;
1319                if (rdev2->raid_disk < 0 ||
1320                    test_bit(Faulty, &rdev2->flags))
1321                        is_active = 0;
1322                if (is_active)
1323                        desc_nr = rdev2->raid_disk;
1324                else
1325                        desc_nr = next_spare++;
1326                rdev2->desc_nr = desc_nr;
1327                d = &sb->disks[rdev2->desc_nr];
1328                nr_disks++;
1329                d->number = rdev2->desc_nr;
1330                d->major = MAJOR(rdev2->bdev->bd_dev);
1331                d->minor = MINOR(rdev2->bdev->bd_dev);
1332                if (is_active)
1333                        d->raid_disk = rdev2->raid_disk;
1334                else
1335                        d->raid_disk = rdev2->desc_nr; /* compatibility */
1336                if (test_bit(Faulty, &rdev2->flags))
1337                        d->state = (1<<MD_DISK_FAULTY);
1338                else if (is_active) {
1339                        d->state = (1<<MD_DISK_ACTIVE);
1340                        if (test_bit(In_sync, &rdev2->flags))
1341                                d->state |= (1<<MD_DISK_SYNC);
1342                        active++;
1343                        working++;
1344                } else {
1345                        d->state = 0;
1346                        spare++;
1347                        working++;
1348                }
1349                if (test_bit(WriteMostly, &rdev2->flags))
1350                        d->state |= (1<<MD_DISK_WRITEMOSTLY);
1351        }
1352        /* now set the "removed" and "faulty" bits on any missing devices */
1353        for (i=0 ; i < mddev->raid_disks ; i++) {
1354                mdp_disk_t *d = &sb->disks[i];
1355                if (d->state == 0 && d->number == 0) {
1356                        d->number = i;
1357                        d->raid_disk = i;
1358                        d->state = (1<<MD_DISK_REMOVED);
1359                        d->state |= (1<<MD_DISK_FAULTY);
1360                        failed++;
1361                }
1362        }
1363        sb->nr_disks = nr_disks;
1364        sb->active_disks = active;
1365        sb->working_disks = working;
1366        sb->failed_disks = failed;
1367        sb->spare_disks = spare;
1368
1369        sb->this_disk = sb->disks[rdev->desc_nr];
1370        sb->sb_csum = calc_sb_csum(sb);
1371}
1372
1373/*
1374 * rdev_size_change for 0.90.0
1375 */
1376static unsigned long long
1377super_90_rdev_size_change(struct md_rdev *rdev, sector_t num_sectors)
1378{
1379        if (num_sectors && num_sectors < rdev->mddev->dev_sectors)
1380                return 0; /* component must fit device */
1381        if (rdev->mddev->bitmap_info.offset)
1382                return 0; /* can't move bitmap */
1383        rdev->sb_start = calc_dev_sboffset(rdev);
1384        if (!num_sectors || num_sectors > rdev->sb_start)
1385                num_sectors = rdev->sb_start;
1386        /* Limit to 4TB as metadata cannot record more than that.
1387         * 4TB == 2^32 KB, or 2*2^32 sectors.
1388         */
1389        if (num_sectors >= (2ULL << 32) && rdev->mddev->level >= 1)
1390                num_sectors = (2ULL << 32) - 2;
1391        md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
1392                       rdev->sb_page);
1393        md_super_wait(rdev->mddev);
1394        return num_sectors;
1395}
1396
1397static int
1398super_90_allow_new_offset(struct md_rdev *rdev, unsigned long long new_offset)
1399{
1400        /* non-zero offset changes not possible with v0.90 */
1401        return new_offset == 0;
1402}
1403
1404/*
1405 * version 1 superblock
1406 */
1407
1408static __le32 calc_sb_1_csum(struct mdp_superblock_1 * sb)
1409{
1410        __le32 disk_csum;
1411        u32 csum;
1412        unsigned long long newcsum;
1413        int size = 256 + le32_to_cpu(sb->max_dev)*2;
1414        __le32 *isuper = (__le32*)sb;
1415
1416        disk_csum = sb->sb_csum;
1417        sb->sb_csum = 0;
1418        newcsum = 0;
1419        for (; size >= 4; size -= 4)
1420                newcsum += le32_to_cpu(*isuper++);
1421
1422        if (size == 2)
1423                newcsum += le16_to_cpu(*(__le16*) isuper);
1424
1425        csum = (newcsum & 0xffffffff) + (newcsum >> 32);
1426        sb->sb_csum = disk_csum;
1427        return cpu_to_le32(csum);
1428}
1429
1430static int md_set_badblocks(struct badblocks *bb, sector_t s, int sectors,
1431                            int acknowledged);
1432static int super_1_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor_version)
1433{
1434        struct mdp_superblock_1 *sb;
1435        int ret;
1436        sector_t sb_start;
1437        sector_t sectors;
1438        char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1439        int bmask;
1440
1441        /*
1442         * Calculate the position of the superblock in 512byte sectors.
1443         * It is always aligned to a 4K boundary and
1444         * depeding on minor_version, it can be:
1445         * 0: At least 8K, but less than 12K, from end of device
1446         * 1: At start of device
1447         * 2: 4K from start of device.
1448         */
1449        switch(minor_version) {
1450        case 0:
1451                sb_start = i_size_read(rdev->bdev->bd_inode) >> 9;
1452                sb_start -= 8*2;
1453                sb_start &= ~(sector_t)(4*2-1);
1454                break;
1455        case 1:
1456                sb_start = 0;
1457                break;
1458        case 2:
1459                sb_start = 8;
1460                break;
1461        default:
1462                return -EINVAL;
1463        }
1464        rdev->sb_start = sb_start;
1465
1466        /* superblock is rarely larger than 1K, but it can be larger,
1467         * and it is safe to read 4k, so we do that
1468         */
1469        ret = read_disk_sb(rdev, 4096);
1470        if (ret) return ret;
1471
1472
1473        sb = page_address(rdev->sb_page);
1474
1475        if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
1476            sb->major_version != cpu_to_le32(1) ||
1477            le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
1478            le64_to_cpu(sb->super_offset) != rdev->sb_start ||
1479            (le32_to_cpu(sb->feature_map) & ~MD_FEATURE_ALL) != 0)
1480                return -EINVAL;
1481
1482        if (calc_sb_1_csum(sb) != sb->sb_csum) {
1483                printk("md: invalid superblock checksum on %s\n",
1484                        bdevname(rdev->bdev,b));
1485                return -EINVAL;
1486        }
1487        if (le64_to_cpu(sb->data_size) < 10) {
1488                printk("md: data_size too small on %s\n",
1489                       bdevname(rdev->bdev,b));
1490                return -EINVAL;
1491        }
1492        if (sb->pad0 ||
1493            sb->pad3[0] ||
1494            memcmp(sb->pad3, sb->pad3+1, sizeof(sb->pad3) - sizeof(sb->pad3[1])))
1495                /* Some padding is non-zero, might be a new feature */
1496                return -EINVAL;
1497
1498        rdev->preferred_minor = 0xffff;
1499        rdev->data_offset = le64_to_cpu(sb->data_offset);
1500        rdev->new_data_offset = rdev->data_offset;
1501        if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE) &&
1502            (le32_to_cpu(sb->feature_map) & MD_FEATURE_NEW_OFFSET))
1503                rdev->new_data_offset += (s32)le32_to_cpu(sb->new_offset);
1504        atomic_set(&rdev->corrected_errors, le32_to_cpu(sb->cnt_corrected_read));
1505
1506        rdev->sb_size = le32_to_cpu(sb->max_dev) * 2 + 256;
1507        bmask = queue_logical_block_size(rdev->bdev->bd_disk->queue)-1;
1508        if (rdev->sb_size & bmask)
1509                rdev->sb_size = (rdev->sb_size | bmask) + 1;
1510
1511        if (minor_version
1512            && rdev->data_offset < sb_start + (rdev->sb_size/512))
1513                return -EINVAL;
1514        if (minor_version
1515            && rdev->new_data_offset < sb_start + (rdev->sb_size/512))
1516                return -EINVAL;
1517
1518        if (sb->level == cpu_to_le32(LEVEL_MULTIPATH))
1519                rdev->desc_nr = -1;
1520        else
1521                rdev->desc_nr = le32_to_cpu(sb->dev_number);
1522
1523        if (!rdev->bb_page) {
1524                rdev->bb_page = alloc_page(GFP_KERNEL);
1525                if (!rdev->bb_page)
1526                        return -ENOMEM;
1527        }
1528        if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BAD_BLOCKS) &&
1529            rdev->badblocks.count == 0) {
1530                /* need to load the bad block list.
1531                 * Currently we limit it to one page.
1532                 */
1533                s32 offset;
1534                sector_t bb_sector;
1535                u64 *bbp;
1536                int i;
1537                int sectors = le16_to_cpu(sb->bblog_size);
1538                if (sectors > (PAGE_SIZE / 512))
1539                        return -EINVAL;
1540                offset = le32_to_cpu(sb->bblog_offset);
1541                if (offset == 0)
1542                        return -EINVAL;
1543                bb_sector = (long long)offset;
1544                if (!sync_page_io(rdev, bb_sector, sectors << 9,
1545                                  rdev->bb_page, READ, true))
1546                        return -EIO;
1547                bbp = (u64 *)page_address(rdev->bb_page);
1548                rdev->badblocks.shift = sb->bblog_shift;
1549                for (i = 0 ; i < (sectors << (9-3)) ; i++, bbp++) {
1550                        u64 bb = le64_to_cpu(*bbp);
1551                        int count = bb & (0x3ff);
1552                        u64 sector = bb >> 10;
1553                        sector <<= sb->bblog_shift;
1554                        count <<= sb->bblog_shift;
1555                        if (bb + 1 == 0)
1556                                break;
1557                        if (md_set_badblocks(&rdev->badblocks,
1558                                             sector, count, 1) == 0)
1559                                return -EINVAL;
1560                }
1561        } else if (sb->bblog_offset != 0)
1562                rdev->badblocks.shift = 0;
1563
1564        if (!refdev) {
1565                ret = 1;
1566        } else {
1567                __u64 ev1, ev2;
1568                struct mdp_superblock_1 *refsb = page_address(refdev->sb_page);
1569
1570                if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
1571                    sb->level != refsb->level ||
1572                    sb->layout != refsb->layout ||
1573                    sb->chunksize != refsb->chunksize) {
1574                        printk(KERN_WARNING "md: %s has strangely different"
1575                                " superblock to %s\n",
1576                                bdevname(rdev->bdev,b),
1577                                bdevname(refdev->bdev,b2));
1578                        return -EINVAL;
1579                }
1580                ev1 = le64_to_cpu(sb->events);
1581                ev2 = le64_to_cpu(refsb->events);
1582
1583                if (ev1 > ev2)
1584                        ret = 1;
1585                else
1586                        ret = 0;
1587        }
1588        if (minor_version) {
1589                sectors = (i_size_read(rdev->bdev->bd_inode) >> 9);
1590                sectors -= rdev->data_offset;
1591        } else
1592                sectors = rdev->sb_start;
1593        if (sectors < le64_to_cpu(sb->data_size))
1594                return -EINVAL;
1595        rdev->sectors = le64_to_cpu(sb->data_size);
1596        return ret;
1597}
1598
1599static int super_1_validate(struct mddev *mddev, struct md_rdev *rdev)
1600{
1601        struct mdp_superblock_1 *sb = page_address(rdev->sb_page);
1602        __u64 ev1 = le64_to_cpu(sb->events);
1603
1604        rdev->raid_disk = -1;
1605        clear_bit(Faulty, &rdev->flags);
1606        clear_bit(In_sync, &rdev->flags);
1607        clear_bit(WriteMostly, &rdev->flags);
1608
1609        if (mddev->raid_disks == 0) {
1610                mddev->major_version = 1;
1611                mddev->patch_version = 0;
1612                mddev->external = 0;
1613                mddev->chunk_sectors = le32_to_cpu(sb->chunksize);
1614                mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);
1615                mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);
1616                mddev->level = le32_to_cpu(sb->level);
1617                mddev->clevel[0] = 0;
1618                mddev->layout = le32_to_cpu(sb->layout);
1619                mddev->raid_disks = le32_to_cpu(sb->raid_disks);
1620                mddev->dev_sectors = le64_to_cpu(sb->size);
1621                mddev->events = ev1;
1622                mddev->bitmap_info.offset = 0;
1623                mddev->bitmap_info.space = 0;
1624                /* Default location for bitmap is 1K after superblock
1625                 * using 3K - total of 4K
1626                 */
1627                mddev->bitmap_info.default_offset = 1024 >> 9;
1628                mddev->bitmap_info.default_space = (4096-1024) >> 9;
1629                mddev->reshape_backwards = 0;
1630
1631                mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
1632                memcpy(mddev->uuid, sb->set_uuid, 16);
1633
1634                mddev->max_disks =  (4096-256)/2;
1635
1636                if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET) &&
1637                    mddev->bitmap_info.file == NULL) {
1638                        mddev->bitmap_info.offset =
1639                                (__s32)le32_to_cpu(sb->bitmap_offset);
1640                        /* Metadata doesn't record how much space is available.
1641                         * For 1.0, we assume we can use up to the superblock
1642                         * if before, else to 4K beyond superblock.
1643                         * For others, assume no change is possible.
1644                         */
1645                        if (mddev->minor_version > 0)
1646                                mddev->bitmap_info.space = 0;
1647                        else if (mddev->bitmap_info.offset > 0)
1648                                mddev->bitmap_info.space =
1649                                        8 - mddev->bitmap_info.offset;
1650                        else
1651                                mddev->bitmap_info.space =
1652                                        -mddev->bitmap_info.offset;
1653                }
1654
1655                if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE)) {
1656                        mddev->reshape_position = le64_to_cpu(sb->reshape_position);
1657                        mddev->delta_disks = le32_to_cpu(sb->delta_disks);
1658                        mddev->new_level = le32_to_cpu(sb->new_level);
1659                        mddev->new_layout = le32_to_cpu(sb->new_layout);
1660                        mddev->new_chunk_sectors = le32_to_cpu(sb->new_chunk);
1661                        if (mddev->delta_disks < 0 ||
1662                            (mddev->delta_disks == 0 &&
1663                             (le32_to_cpu(sb->feature_map)
1664                              & MD_FEATURE_RESHAPE_BACKWARDS)))
1665                                mddev->reshape_backwards = 1;
1666                } else {
1667                        mddev->reshape_position = MaxSector;
1668                        mddev->delta_disks = 0;
1669                        mddev->new_level = mddev->level;
1670                        mddev->new_layout = mddev->layout;
1671                        mddev->new_chunk_sectors = mddev->chunk_sectors;
1672                }
1673
1674        } else if (mddev->pers == NULL) {
1675                /* Insist of good event counter while assembling, except for
1676                 * spares (which don't need an event count) */
1677                ++ev1;
1678                if (rdev->desc_nr >= 0 &&
1679                    rdev->desc_nr < le32_to_cpu(sb->max_dev) &&
1680                    le16_to_cpu(sb->dev_roles[rdev->desc_nr]) < 0xfffe)
1681                        if (ev1 < mddev->events)
1682                                return -EINVAL;
1683        } else if (mddev->bitmap) {
1684                /* If adding to array with a bitmap, then we can accept an
1685                 * older device, but not too old.
1686                 */
1687                if (ev1 < mddev->bitmap->events_cleared)
1688                        return 0;
1689        } else {
1690                if (ev1 < mddev->events)
1691                        /* just a hot-add of a new device, leave raid_disk at -1 */
1692                        return 0;
1693        }
1694        if (mddev->level != LEVEL_MULTIPATH) {
1695                int role;
1696                if (rdev->desc_nr < 0 ||
1697                    rdev->desc_nr >= le32_to_cpu(sb->max_dev)) {
1698                        role = 0xffff;
1699                        rdev->desc_nr = -1;
1700                } else
1701                        role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
1702                switch(role) {
1703                case 0xffff: /* spare */
1704                        break;
1705                case 0xfffe: /* faulty */
1706                        set_bit(Faulty, &rdev->flags);
1707                        break;
1708                default:
1709                        if ((le32_to_cpu(sb->feature_map) &
1710                             MD_FEATURE_RECOVERY_OFFSET))
1711                                rdev->recovery_offset = le64_to_cpu(sb->recovery_offset);
1712                        else
1713                                set_bit(In_sync, &rdev->flags);
1714                        rdev->raid_disk = role;
1715                        break;
1716                }
1717                if (sb->devflags & WriteMostly1)
1718                        set_bit(WriteMostly, &rdev->flags);
1719                if (le32_to_cpu(sb->feature_map) & MD_FEATURE_REPLACEMENT)
1720                        set_bit(Replacement, &rdev->flags);
1721        } else /* MULTIPATH are always insync */
1722                set_bit(In_sync, &rdev->flags);
1723
1724        return 0;
1725}
1726
1727static void super_1_sync(struct mddev *mddev, struct md_rdev *rdev)
1728{
1729        struct mdp_superblock_1 *sb;
1730        struct md_rdev *rdev2;
1731        int max_dev, i;
1732        /* make rdev->sb match mddev and rdev data. */
1733
1734        sb = page_address(rdev->sb_page);
1735
1736        sb->feature_map = 0;
1737        sb->pad0 = 0;
1738        sb->recovery_offset = cpu_to_le64(0);
1739        memset(sb->pad3, 0, sizeof(sb->pad3));
1740
1741        sb->utime = cpu_to_le64((__u64)mddev->utime);
1742        sb->events = cpu_to_le64(mddev->events);
1743        if (mddev->in_sync)
1744                sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
1745        else
1746                sb->resync_offset = cpu_to_le64(0);
1747
1748        sb->cnt_corrected_read = cpu_to_le32(atomic_read(&rdev->corrected_errors));
1749
1750        sb->raid_disks = cpu_to_le32(mddev->raid_disks);
1751        sb->size = cpu_to_le64(mddev->dev_sectors);
1752        sb->chunksize = cpu_to_le32(mddev->chunk_sectors);
1753        sb->level = cpu_to_le32(mddev->level);
1754        sb->layout = cpu_to_le32(mddev->layout);
1755
1756        if (test_bit(WriteMostly, &rdev->flags))
1757                sb->devflags |= WriteMostly1;
1758        else
1759                sb->devflags &= ~WriteMostly1;
1760        sb->data_offset = cpu_to_le64(rdev->data_offset);
1761        sb->data_size = cpu_to_le64(rdev->sectors);
1762
1763        if (mddev->bitmap && mddev->bitmap_info.file == NULL) {
1764                sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_info.offset);
1765                sb->feature_map = cpu_to_le32(MD_FEATURE_BITMAP_OFFSET);
1766        }
1767
1768        if (rdev->raid_disk >= 0 &&
1769            !test_bit(In_sync, &rdev->flags)) {
1770                sb->feature_map |=
1771                        cpu_to_le32(MD_FEATURE_RECOVERY_OFFSET);
1772                sb->recovery_offset =
1773                        cpu_to_le64(rdev->recovery_offset);
1774        }
1775        if (test_bit(Replacement, &rdev->flags))
1776                sb->feature_map |=
1777                        cpu_to_le32(MD_FEATURE_REPLACEMENT);
1778
1779        if (mddev->reshape_position != MaxSector) {
1780                sb->feature_map |= cpu_to_le32(MD_FEATURE_RESHAPE_ACTIVE);
1781                sb->reshape_position = cpu_to_le64(mddev->reshape_position);
1782                sb->new_layout = cpu_to_le32(mddev->new_layout);
1783                sb->delta_disks = cpu_to_le32(mddev->delta_disks);
1784                sb->new_level = cpu_to_le32(mddev->new_level);
1785                sb->new_chunk = cpu_to_le32(mddev->new_chunk_sectors);
1786                if (mddev->delta_disks == 0 &&
1787                    mddev->reshape_backwards)
1788                        sb->feature_map
1789                                |= cpu_to_le32(MD_FEATURE_RESHAPE_BACKWARDS);
1790                if (rdev->new_data_offset != rdev->data_offset) {
1791                        sb->feature_map
1792                                |= cpu_to_le32(MD_FEATURE_NEW_OFFSET);
1793                        sb->new_offset = cpu_to_le32((__u32)(rdev->new_data_offset
1794                                                             - rdev->data_offset));
1795                }
1796        }
1797
1798        if (rdev->badblocks.count == 0)
1799                /* Nothing to do for bad blocks*/ ;
1800        else if (sb->bblog_offset == 0)
1801                /* Cannot record bad blocks on this device */
1802                md_error(mddev, rdev);
1803        else {
1804                struct badblocks *bb = &rdev->badblocks;
1805                u64 *bbp = (u64 *)page_address(rdev->bb_page);
1806                u64 *p = bb->page;
1807                sb->feature_map |= cpu_to_le32(MD_FEATURE_BAD_BLOCKS);
1808                if (bb->changed) {
1809                        unsigned seq;
1810
1811retry:
1812                        seq = read_seqbegin(&bb->lock);
1813
1814                        memset(bbp, 0xff, PAGE_SIZE);
1815
1816                        for (i = 0 ; i < bb->count ; i++) {
1817                                u64 internal_bb = p[i];
1818                                u64 store_bb = ((BB_OFFSET(internal_bb) << 10)
1819                                                | BB_LEN(internal_bb));
1820                                bbp[i] = cpu_to_le64(store_bb);
1821                        }
1822                        bb->changed = 0;
1823                        if (read_seqretry(&bb->lock, seq))
1824                                goto retry;
1825
1826                        bb->sector = (rdev->sb_start +
1827                                      (int)le32_to_cpu(sb->bblog_offset));
1828                        bb->size = le16_to_cpu(sb->bblog_size);
1829                }
1830        }
1831
1832        max_dev = 0;
1833        rdev_for_each(rdev2, mddev)
1834                if (rdev2->desc_nr+1 > max_dev)
1835                        max_dev = rdev2->desc_nr+1;
1836
1837        if (max_dev > le32_to_cpu(sb->max_dev)) {
1838                int bmask;
1839                sb->max_dev = cpu_to_le32(max_dev);
1840                rdev->sb_size = max_dev * 2 + 256;
1841                bmask = queue_logical_block_size(rdev->bdev->bd_disk->queue)-1;
1842                if (rdev->sb_size & bmask)
1843                        rdev->sb_size = (rdev->sb_size | bmask) + 1;
1844        } else
1845                max_dev = le32_to_cpu(sb->max_dev);
1846
1847        for (i=0; i<max_dev;i++)
1848                sb->dev_roles[i] = cpu_to_le16(0xfffe);
1849        
1850        rdev_for_each(rdev2, mddev) {
1851                i = rdev2->desc_nr;
1852                if (test_bit(Faulty, &rdev2->flags))
1853                        sb->dev_roles[i] = cpu_to_le16(0xfffe);
1854                else if (test_bit(In_sync, &rdev2->flags))
1855                        sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1856                else if (rdev2->raid_disk >= 0)
1857                        sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1858                else
1859                        sb->dev_roles[i] = cpu_to_le16(0xffff);
1860        }
1861
1862        sb->sb_csum = calc_sb_1_csum(sb);
1863}
1864
1865static unsigned long long
1866super_1_rdev_size_change(struct md_rdev *rdev, sector_t num_sectors)
1867{
1868        struct mdp_superblock_1 *sb;
1869        sector_t max_sectors;
1870        if (num_sectors && num_sectors < rdev->mddev->dev_sectors)
1871                return 0; /* component must fit device */
1872        if (rdev->data_offset != rdev->new_data_offset)
1873                return 0; /* too confusing */
1874        if (rdev->sb_start < rdev->data_offset) {
1875                /* minor versions 1 and 2; superblock before data */
1876                max_sectors = i_size_read(rdev->bdev->bd_inode) >> 9;
1877                max_sectors -= rdev->data_offset;
1878                if (!num_sectors || num_sectors > max_sectors)
1879                        num_sectors = max_sectors;
1880        } else if (rdev->mddev->bitmap_info.offset) {
1881                /* minor version 0 with bitmap we can't move */
1882                return 0;
1883        } else {
1884                /* minor version 0; superblock after data */
1885                sector_t sb_start;
1886                sb_start = (i_size_read(rdev->bdev->bd_inode) >> 9) - 8*2;
1887                sb_start &= ~(sector_t)(4*2 - 1);
1888                max_sectors = rdev->sectors + sb_start - rdev->sb_start;
1889                if (!num_sectors || num_sectors > max_sectors)
1890                        num_sectors = max_sectors;
1891                rdev->sb_start = sb_start;
1892        }
1893        sb = page_address(rdev->sb_page);
1894        sb->data_size = cpu_to_le64(num_sectors);
1895        sb->super_offset = rdev->sb_start;
1896        sb->sb_csum = calc_sb_1_csum(sb);
1897        md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
1898                       rdev->sb_page);
1899        md_super_wait(rdev->mddev);
1900        return num_sectors;
1901
1902}
1903
1904static int
1905super_1_allow_new_offset(struct md_rdev *rdev,
1906                         unsigned long long new_offset)
1907{
1908        /* All necessary checks on new >= old have been done */
1909        struct bitmap *bitmap;
1910        if (new_offset >= rdev->data_offset)
1911                return 1;
1912
1913        /* with 1.0 metadata, there is no metadata to tread on
1914         * so we can always move back */
1915        if (rdev->mddev->minor_version == 0)
1916                return 1;
1917
1918        /* otherwise we must be sure not to step on
1919         * any metadata, so stay:
1920         * 36K beyond start of superblock
1921         * beyond end of badblocks
1922         * beyond write-intent bitmap
1923         */
1924        if (rdev->sb_start + (32+4)*2 > new_offset)
1925                return 0;
1926        bitmap = rdev->mddev->bitmap;
1927        if (bitmap && !rdev->mddev->bitmap_info.file &&
1928            rdev->sb_start + rdev->mddev->bitmap_info.offset +
1929            bitmap->storage.file_pages * (PAGE_SIZE>>9) > new_offset)
1930                return 0;
1931        if (rdev->badblocks.sector + rdev->badblocks.size > new_offset)
1932                return 0;
1933
1934        return 1;
1935}
1936
1937static struct super_type super_types[] = {
1938        [0] = {
1939                .name   = "0.90.0",
1940                .owner  = THIS_MODULE,
1941                .load_super         = super_90_load,
1942                .validate_super     = super_90_validate,
1943                .sync_super         = super_90_sync,
1944                .rdev_size_change   = super_90_rdev_size_change,
1945                .allow_new_offset   = super_90_allow_new_offset,
1946        },
1947        [1] = {
1948                .name   = "md-1",
1949                .owner  = THIS_MODULE,
1950                .load_super         = super_1_load,
1951                .validate_super     = super_1_validate,
1952                .sync_super         = super_1_sync,
1953                .rdev_size_change   = super_1_rdev_size_change,
1954                .allow_new_offset   = super_1_allow_new_offset,
1955        },
1956};
1957
1958static void sync_super(struct mddev *mddev, struct md_rdev *rdev)
1959{
1960        if (mddev->sync_super) {
1961                mddev->sync_super(mddev, rdev);
1962                return;
1963        }
1964
1965        BUG_ON(mddev->major_version >= ARRAY_SIZE(super_types));
1966
1967        super_types[mddev->major_version].sync_super(mddev, rdev);
1968}
1969
1970static int match_mddev_units(struct mddev *mddev1, struct mddev *mddev2)
1971{
1972        struct md_rdev *rdev, *rdev2;
1973
1974        rcu_read_lock();
1975        rdev_for_each_rcu(rdev, mddev1)
1976                rdev_for_each_rcu(rdev2, mddev2)
1977                        if (rdev->bdev->bd_contains ==
1978                            rdev2->bdev->bd_contains) {
1979                                rcu_read_unlock();
1980                                return 1;
1981                        }
1982        rcu_read_unlock();
1983        return 0;
1984}
1985
1986static LIST_HEAD(pending_raid_disks);
1987
1988/*
1989 * Try to register data integrity profile for an mddev
1990 *
1991 * This is called when an array is started and after a disk has been kicked
1992 * from the array. It only succeeds if all working and active component devices
1993 * are integrity capable with matching profiles.
1994 */
1995int md_integrity_register(struct mddev *mddev)
1996{
1997        struct md_rdev *rdev, *reference = NULL;
1998
1999        if (list_empty(&mddev->disks))
2000                return 0; /* nothing to do */
2001        if (!mddev->gendisk || blk_get_integrity(mddev->gendisk))
2002                return 0; /* shouldn't register, or already is */
2003        rdev_for_each(rdev, mddev) {
2004                /* skip spares and non-functional disks */
2005                if (test_bit(Faulty, &rdev->flags))
2006                        continue;
2007                if (rdev->raid_disk < 0)
2008                        continue;
2009                if (!reference) {
2010                        /* Use the first rdev as the reference */
2011                        reference = rdev;
2012                        continue;
2013                }
2014                /* does this rdev's profile match the reference profile? */
2015                if (blk_integrity_compare(reference->bdev->bd_disk,
2016                                rdev->bdev->bd_disk) < 0)
2017                        return -EINVAL;
2018        }
2019        if (!reference || !bdev_get_integrity(reference->bdev))
2020                return 0;
2021        /*
2022         * All component devices are integrity capable and have matching
2023         * profiles, register the common profile for the md device.
2024         */
2025        if (blk_integrity_register(mddev->gendisk,
2026                        bdev_get_integrity(reference->bdev)) != 0) {
2027                printk(KERN_ERR "md: failed to register integrity for %s\n",
2028                        mdname(mddev));
2029                return -EINVAL;
2030        }
2031        printk(KERN_NOTICE "md: data integrity enabled on %s\n", mdname(mddev));
2032        if (bioset_integrity_create(mddev->bio_set, BIO_POOL_SIZE)) {
2033                printk(KERN_ERR "md: failed to create integrity pool for %s\n",
2034                       mdname(mddev));
2035                return -EINVAL;
2036        }
2037        return 0;
2038}
2039EXPORT_SYMBOL(md_integrity_register);
2040
2041/* Disable data integrity if non-capable/non-matching disk is being added */
2042void md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev)
2043{
2044        struct blk_integrity *bi_rdev;
2045        struct blk_integrity *bi_mddev;
2046
2047        if (!mddev->gendisk)
2048                return;
2049
2050        bi_rdev = bdev_get_integrity(rdev->bdev);
2051        bi_mddev = blk_get_integrity(mddev->gendisk);
2052
2053        if (!bi_mddev) /* nothing to do */
2054                return;
2055        if (rdev->raid_disk < 0) /* skip spares */
2056                return;
2057        if (bi_rdev && blk_integrity_compare(mddev->gendisk,
2058                                             rdev->bdev->bd_disk) >= 0)
2059                return;
2060        printk(KERN_NOTICE "disabling data integrity on %s\n", mdname(mddev));
2061        blk_integrity_unregister(mddev->gendisk);
2062}
2063EXPORT_SYMBOL(md_integrity_add_rdev);
2064
2065static int bind_rdev_to_array(struct md_rdev * rdev, struct mddev * mddev)
2066{
2067        char b[BDEVNAME_SIZE];
2068        struct kobject *ko;
2069        char *s;
2070        int err;
2071
2072        if (rdev->mddev) {
2073                MD_BUG();
2074                return -EINVAL;
2075        }
2076
2077        /* prevent duplicates */
2078        if (find_rdev(mddev, rdev->bdev->bd_dev))
2079                return -EEXIST;
2080
2081        /* make sure rdev->sectors exceeds mddev->dev_sectors */
2082        if (rdev->sectors && (mddev->dev_sectors == 0 ||
2083                        rdev->sectors < mddev->dev_sectors)) {
2084                if (mddev->pers) {
2085                        /* Cannot change size, so fail
2086                         * If mddev->level <= 0, then we don't care
2087                         * about aligning sizes (e.g. linear)
2088                         */
2089                        if (mddev->level > 0)
2090                                return -ENOSPC;
2091                } else
2092                        mddev->dev_sectors = rdev->sectors;
2093        }
2094
2095        /* Verify rdev->desc_nr is unique.
2096         * If it is -1, assign a free number, else
2097         * check number is not in use
2098         */
2099        if (rdev->desc_nr < 0) {
2100                int choice = 0;
2101                if (mddev->pers) choice = mddev->raid_disks;
2102                while (find_rdev_nr(mddev, choice))
2103                        choice++;
2104                rdev->desc_nr = choice;
2105        } else {
2106                if (find_rdev_nr(mddev, rdev->desc_nr))
2107                        return -EBUSY;
2108        }
2109        if (mddev->max_disks && rdev->desc_nr >= mddev->max_disks) {
2110                printk(KERN_WARNING "md: %s: array is limited to %d devices\n",
2111                       mdname(mddev), mddev->max_disks);
2112                return -EBUSY;
2113        }
2114        bdevname(rdev->bdev,b);
2115        while ( (s=strchr(b, '/')) != NULL)
2116                *s = '!';
2117
2118        rdev->mddev = mddev;
2119        printk(KERN_INFO "md: bind<%s>\n", b);
2120
2121        if ((err = kobject_add(&rdev->kobj, &mddev->kobj, "dev-%s", b)))
2122                goto fail;
2123
2124        ko = &part_to_dev(rdev->bdev->bd_part)->kobj;
2125        if (sysfs_create_link(&rdev->kobj, ko, "block"))
2126                /* failure here is OK */;
2127        rdev->sysfs_state = sysfs_get_dirent_safe(rdev->kobj.sd, "state");
2128
2129        list_add_rcu(&rdev->same_set, &mddev->disks);
2130        bd_link_disk_holder(rdev->bdev, mddev->gendisk);
2131
2132        /* May as well allow recovery to be retried once */
2133        mddev->recovery_disabled++;
2134
2135        return 0;
2136
2137 fail:
2138        printk(KERN_WARNING "md: failed to register dev-%s for %s\n",
2139               b, mdname(mddev));
2140        return err;
2141}
2142
2143static void md_delayed_delete(struct work_struct *ws)
2144{
2145        struct md_rdev *rdev = container_of(ws, struct md_rdev, del_work);
2146        kobject_del(&rdev->kobj);
2147        kobject_put(&rdev->kobj);
2148}
2149
2150static void unbind_rdev_from_array(struct md_rdev * rdev)
2151{
2152        char b[BDEVNAME_SIZE];
2153        if (!rdev->mddev) {
2154                MD_BUG();
2155                return;
2156        }
2157        bd_unlink_disk_holder(rdev->bdev, rdev->mddev->gendisk);
2158        list_del_rcu(&rdev->same_set);
2159        printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
2160        rdev->mddev = NULL;
2161        sysfs_remove_link(&rdev->kobj, "block");
2162        sysfs_put(rdev->sysfs_state);
2163        rdev->sysfs_state = NULL;
2164        rdev->badblocks.count = 0;
2165        /* We need to delay this, otherwise we can deadlock when
2166         * writing to 'remove' to "dev/state".  We also need
2167         * to delay it due to rcu usage.
2168         */
2169        synchronize_rcu();
2170        INIT_WORK(&rdev->del_work, md_delayed_delete);
2171        kobject_get(&rdev->kobj);
2172        queue_work(md_misc_wq, &rdev->del_work);
2173}
2174
2175/*
2176 * prevent the device from being mounted, repartitioned or
2177 * otherwise reused by a RAID array (or any other kernel
2178 * subsystem), by bd_claiming the device.
2179 */
2180static int lock_rdev(struct md_rdev *rdev, dev_t dev, int shared)
2181{
2182        int err = 0;
2183        struct block_device *bdev;
2184        char b[BDEVNAME_SIZE];
2185
2186        bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL,
2187                                 shared ? (struct md_rdev *)lock_rdev : rdev);
2188        if (IS_ERR(bdev)) {
2189                printk(KERN_ERR "md: could not open %s.\n",
2190                        __bdevname(dev, b));
2191                return PTR_ERR(bdev);
2192        }
2193        rdev->bdev = bdev;
2194        return err;
2195}
2196
2197static void unlock_rdev(struct md_rdev *rdev)
2198{
2199        struct block_device *bdev = rdev->bdev;
2200        rdev->bdev = NULL;
2201        if (!bdev)
2202                MD_BUG();
2203        blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
2204}
2205
2206void md_autodetect_dev(dev_t dev);
2207
2208static void export_rdev(struct md_rdev * rdev)
2209{
2210        char b[BDEVNAME_SIZE];
2211        printk(KERN_INFO "md: export_rdev(%s)\n",
2212                bdevname(rdev->bdev,b));
2213        if (rdev->mddev)
2214                MD_BUG();
2215        md_rdev_clear(rdev);
2216#ifndef MODULE
2217        if (test_bit(AutoDetected, &rdev->flags))
2218                md_autodetect_dev(rdev->bdev->bd_dev);
2219#endif
2220        unlock_rdev(rdev);
2221        kobject_put(&rdev->kobj);
2222}
2223
2224static void kick_rdev_from_array(struct md_rdev * rdev)
2225{
2226        unbind_rdev_from_array(rdev);
2227        export_rdev(rdev);
2228}
2229
2230static void export_array(struct mddev *mddev)
2231{
2232        struct md_rdev *rdev, *tmp;
2233
2234        rdev_for_each_safe(rdev, tmp, mddev) {
2235                if (!rdev->mddev) {
2236                        MD_BUG();
2237                        continue;
2238                }
2239                kick_rdev_from_array(rdev);
2240        }
2241        if (!list_empty(&mddev->disks))
2242                MD_BUG();
2243        mddev->raid_disks = 0;
2244        mddev->major_version = 0;
2245}
2246
2247static void print_desc(mdp_disk_t *desc)
2248{
2249        printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
2250                desc->major,desc->minor,desc->raid_disk,desc->state);
2251}
2252
2253static void print_sb_90(mdp_super_t *sb)
2254{
2255        int i;
2256
2257        printk(KERN_INFO 
2258                "md:  SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
2259                sb->major_version, sb->minor_version, sb->patch_version,
2260                sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
2261                sb->ctime);
2262        printk(KERN_INFO "md:     L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
2263                sb->level, sb->size, sb->nr_disks, sb->raid_disks,
2264                sb->md_minor, sb->layout, sb->chunk_size);
2265        printk(KERN_INFO "md:     UT:%08x ST:%d AD:%d WD:%d"
2266                " FD:%d SD:%d CSUM:%08x E:%08lx\n",
2267                sb->utime, sb->state, sb->active_disks, sb->working_disks,
2268                sb->failed_disks, sb->spare_disks,
2269                sb->sb_csum, (unsigned long)sb->events_lo);
2270
2271        printk(KERN_INFO);
2272        for (i = 0; i < MD_SB_DISKS; i++) {
2273                mdp_disk_t *desc;
2274
2275                desc = sb->disks + i;
2276                if (desc->number || desc->major || desc->minor ||
2277                    desc->raid_disk || (desc->state && (desc->state != 4))) {
2278                        printk("     D %2d: ", i);
2279                        print_desc(desc);
2280                }
2281        }
2282        printk(KERN_INFO "md:     THIS: ");
2283        print_desc(&sb->this_disk);
2284}
2285
2286static void print_sb_1(struct mdp_superblock_1 *sb)
2287{
2288        __u8 *uuid;
2289
2290        uuid = sb->set_uuid;
2291        printk(KERN_INFO
2292               "md:  SB: (V:%u) (F:0x%08x) Array-ID:<%pU>\n"
2293               "md:    Name: \"%s\" CT:%llu\n",
2294                le32_to_cpu(sb->major_version),
2295                le32_to_cpu(sb->feature_map),
2296                uuid,
2297                sb->set_name,
2298                (unsigned long long)le64_to_cpu(sb->ctime)
2299                       & MD_SUPERBLOCK_1_TIME_SEC_MASK);
2300
2301        uuid = sb->device_uuid;
2302        printk(KERN_INFO
2303               "md:       L%u SZ%llu RD:%u LO:%u CS:%u DO:%llu DS:%llu SO:%llu"
2304                        " RO:%llu\n"
2305               "md:     Dev:%08x UUID: %pU\n"
2306               "md:       (F:0x%08x) UT:%llu Events:%llu ResyncOffset:%llu CSUM:0x%08x\n"
2307               "md:         (MaxDev:%u) \n",
2308                le32_to_cpu(sb->level),
2309                (unsigned long long)le64_to_cpu(sb->size),
2310                le32_to_cpu(sb->raid_disks),
2311                le32_to_cpu(sb->layout),
2312                le32_to_cpu(sb->chunksize),
2313                (unsigned long long)le64_to_cpu(sb->data_offset),
2314                (unsigned long long)le64_to_cpu(sb->data_size),
2315                (unsigned long long)le64_to_cpu(sb->super_offset),
2316                (unsigned long long)le64_to_cpu(sb->recovery_offset),
2317                le32_to_cpu(sb->dev_number),
2318                uuid,
2319                sb->devflags,
2320                (unsigned long long)le64_to_cpu(sb->utime) & MD_SUPERBLOCK_1_TIME_SEC_MASK,
2321                (unsigned long long)le64_to_cpu(sb->events),
2322                (unsigned long long)le64_to_cpu(sb->resync_offset),
2323                le32_to_cpu(sb->sb_csum),
2324                le32_to_cpu(sb->max_dev)
2325                );
2326}
2327
2328static void print_rdev(struct md_rdev *rdev, int major_version)
2329{
2330        char b[BDEVNAME_SIZE];
2331        printk(KERN_INFO "md: rdev %s, Sect:%08llu F:%d S:%d DN:%u\n",
2332                bdevname(rdev->bdev, b), (unsigned long long)rdev->sectors,
2333                test_bit(Faulty, &rdev->flags), test_bit(In_sync, &rdev->flags),
2334                rdev->desc_nr);
2335        if (rdev->sb_loaded) {
2336                printk(KERN_INFO "md: rdev superblock (MJ:%d):\n", major_version);
2337                switch (major_version) {
2338                case 0:
2339                        print_sb_90(page_address(rdev->sb_page));
2340                        break;
2341                case 1:
2342                        print_sb_1(page_address(rdev->sb_page));
2343                        break;
2344                }
2345        } else
2346                printk(KERN_INFO "md: no rdev superblock!\n");
2347}
2348
2349static void md_print_devices(void)
2350{
2351        struct list_head *tmp;
2352        struct md_rdev *rdev;
2353        struct mddev *mddev;
2354        char b[BDEVNAME_SIZE];
2355
2356        printk("\n");
2357        printk("md:     **********************************\n");
2358        printk("md:     * <COMPLETE RAID STATE PRINTOUT> *\n");
2359        printk("md:     **********************************\n");
2360        for_each_mddev(mddev, tmp) {
2361
2362                if (mddev->bitmap)
2363                        bitmap_print_sb(mddev->bitmap);
2364                else
2365                        printk("%s: ", mdname(mddev));
2366                rdev_for_each(rdev, mddev)
2367                        printk("<%s>", bdevname(rdev->bdev,b));
2368                printk("\n");
2369
2370                rdev_for_each(rdev, mddev)
2371                        print_rdev(rdev, mddev->major_version);
2372        }
2373        printk("md:     **********************************\n");
2374        printk("\n");
2375}
2376
2377
2378static void sync_sbs(struct mddev * mddev, int nospares)
2379{
2380        /* Update each superblock (in-memory image), but
2381         * if we are allowed to, skip spares which already
2382         * have the right event counter, or have one earlier
2383         * (which would mean they aren't being marked as dirty
2384         * with the rest of the array)
2385         */
2386        struct md_rdev *rdev;
2387        rdev_for_each(rdev, mddev) {
2388                if (rdev->sb_events == mddev->events ||
2389                    (nospares &&
2390                     rdev->raid_disk < 0 &&
2391                     rdev->sb_events+1 == mddev->events)) {
2392                        /* Don't update this superblock */
2393                        rdev->sb_loaded = 2;
2394                } else {
2395                        sync_super(mddev, rdev);
2396                        rdev->sb_loaded = 1;
2397                }
2398        }
2399}
2400
2401static void md_update_sb(struct mddev * mddev, int force_change)
2402{
2403        struct md_rdev *rdev;
2404        int sync_req;
2405        int nospares = 0;
2406        int any_badblocks_changed = 0;
2407
2408        if (mddev->ro) {
2409                if (force_change)
2410                        set_bit(MD_CHANGE_DEVS, &mddev->flags);
2411                return;
2412        }
2413repeat:
2414        /* First make sure individual recovery_offsets are correct */
2415        rdev_for_each(rdev, mddev) {
2416                if (rdev->raid_disk >= 0 &&
2417                    mddev->delta_disks >= 0 &&
2418                    !test_bit(In_sync, &rdev->flags) &&
2419                    mddev->curr_resync_completed > rdev->recovery_offset)
2420                                rdev->recovery_offset = mddev->curr_resync_completed;
2421
2422        }       
2423        if (!mddev->persistent) {
2424                clear_bit(MD_CHANGE_CLEAN, &mddev->flags);
2425                clear_bit(MD_CHANGE_DEVS, &mddev->flags);
2426                if (!mddev->external) {
2427                        clear_bit(MD_CHANGE_PENDING, &mddev->flags);
2428                        rdev_for_each(rdev, mddev) {
2429                                if (rdev->badblocks.changed) {
2430                                        rdev->badblocks.changed = 0;
2431                                        md_ack_all_badblocks(&rdev->badblocks);
2432                                        md_error(mddev, rdev);
2433                                }
2434                                clear_bit(Blocked, &rdev->flags);
2435                                clear_bit(BlockedBadBlocks, &rdev->flags);
2436                                wake_up(&rdev->blocked_wait);
2437                        }
2438                }
2439                wake_up(&mddev->sb_wait);
2440                return;
2441        }
2442
2443        spin_lock_irq(&mddev->write_lock);
2444
2445        mddev->utime = get_seconds();
2446
2447        if (test_and_clear_bit(MD_CHANGE_DEVS, &mddev->flags))
2448                force_change = 1;
2449        if (test_and_clear_bit(MD_CHANGE_CLEAN, &mddev->flags))
2450                /* just a clean<-> dirty transition, possibly leave spares alone,
2451                 * though if events isn't the right even/odd, we will have to do
2452                 * spares after all
2453                 */
2454                nospares = 1;
2455        if (force_change)
2456                nospares = 0;
2457        if (mddev->degraded)
2458                /* If the array is degraded, then skipping spares is both
2459                 * dangerous and fairly pointless.
2460                 * Dangerous because a device that was removed from the array
2461                 * might have a event_count that still looks up-to-date,
2462                 * so it can be re-added without a resync.
2463                 * Pointless because if there are any spares to skip,
2464                 * then a recovery will happen and soon that array won't
2465                 * be degraded any more and the spare can go back to sleep then.
2466                 */
2467                nospares = 0;
2468
2469        sync_req = mddev->in_sync;
2470
2471        /* If this is just a dirty<->clean transition, and the array is clean
2472         * and 'events' is odd, we can roll back to the previous clean state */
2473        if (nospares
2474            && (mddev->in_sync && mddev->recovery_cp == MaxSector)
2475            && mddev->can_decrease_events
2476            && mddev->events != 1) {
2477                mddev->events--;
2478                mddev->can_decrease_events = 0;
2479        } else {
2480                /* otherwise we have to go forward and ... */
2481                mddev->events ++;
2482                mddev->can_decrease_events = nospares;
2483        }
2484
2485        if (!mddev->events) {
2486                /*
2487                 * oops, this 64-bit counter should never wrap.
2488                 * Either we are in around ~1 trillion A.C., assuming
2489                 * 1 reboot per second, or we have a bug:
2490                 */
2491                MD_BUG();
2492                mddev->events --;
2493        }
2494
2495        rdev_for_each(rdev, mddev) {
2496                if (rdev->badblocks.changed)
2497                        any_badblocks_changed++;
2498                if (test_bit(Faulty, &rdev->flags))
2499                        set_bit(FaultRecorded, &rdev->flags);
2500        }
2501
2502        sync_sbs(mddev, nospares);
2503        spin_unlock_irq(&mddev->write_lock);
2504
2505        pr_debug("md: updating %s RAID superblock on device (in sync %d)\n",
2506                 mdname(mddev), mddev->in_sync);
2507
2508        bitmap_update_sb(mddev->bitmap);
2509        rdev_for_each(rdev, mddev) {
2510                char b[BDEVNAME_SIZE];
2511
2512                if (rdev->sb_loaded != 1)
2513                        continue; /* no noise on spare devices */
2514
2515                if (!test_bit(Faulty, &rdev->flags) &&
2516                    rdev->saved_raid_disk == -1) {
2517                        md_super_write(mddev,rdev,
2518                                       rdev->sb_start, rdev->sb_size,
2519                                       rdev->sb_page);
2520                        pr_debug("md: (write) %s's sb offset: %llu\n",
2521                                 bdevname(rdev->bdev, b),
2522                                 (unsigned long long)rdev->sb_start);
2523                        rdev->sb_events = mddev->events;
2524                        if (rdev->badblocks.size) {
2525                                md_super_write(mddev, rdev,
2526                                               rdev->badblocks.sector,
2527                                               rdev->badblocks.size << 9,
2528                                               rdev->bb_page);
2529                                rdev->badblocks.size = 0;
2530                        }
2531
2532                } else if (test_bit(Faulty, &rdev->flags))
2533                        pr_debug("md: %s (skipping faulty)\n",
2534                                 bdevname(rdev->bdev, b));
2535                else
2536                        pr_debug("(skipping incremental s/r ");
2537
2538                if (mddev->level == LEVEL_MULTIPATH)
2539                        /* only need to write one superblock... */
2540                        break;
2541        }
2542        md_super_wait(mddev);
2543        /* if there was a failure, MD_CHANGE_DEVS was set, and we re-write super */
2544
2545        spin_lock_irq(&mddev->write_lock);
2546        if (mddev->in_sync != sync_req ||
2547            test_bit(MD_CHANGE_DEVS, &mddev->flags)) {
2548                /* have to write it out again */
2549                spin_unlock_irq(&mddev->write_lock);
2550                goto repeat;
2551        }
2552        clear_bit(MD_CHANGE_PENDING, &mddev->flags);
2553        spin_unlock_irq(&mddev->write_lock);
2554        wake_up(&mddev->sb_wait);
2555        if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
2556                sysfs_notify(&mddev->kobj, NULL, "sync_completed");
2557
2558        rdev_for_each(rdev, mddev) {
2559                if (test_and_clear_bit(FaultRecorded, &rdev->flags))
2560                        clear_bit(Blocked, &rdev->flags);
2561
2562                if (any_badblocks_changed)
2563                        md_ack_all_badblocks(&rdev->badblocks);
2564                clear_bit(BlockedBadBlocks, &rdev->flags);
2565                wake_up(&rdev->blocked_wait);
2566        }
2567}
2568
2569/* words written to sysfs files may, or may not, be \n terminated.
2570 * We want to accept with case. For this we use cmd_match.
2571 */
2572static int cmd_match(const char *cmd, const char *str)
2573{
2574        /* See if cmd, written into a sysfs file, matches
2575         * str.  They must either be the same, or cmd can
2576         * have a trailing newline
2577         */
2578        while (*cmd && *str && *cmd == *str) {
2579                cmd++;
2580                str++;
2581        }
2582        if (*cmd == '\n')
2583                cmd++;
2584        if (*str || *cmd)
2585                return 0;
2586        return 1;
2587}
2588
2589struct rdev_sysfs_entry {
2590        struct attribute attr;
2591        ssize_t (*show)(struct md_rdev *, char *);
2592        ssize_t (*store)(struct md_rdev *, const char *, size_t);
2593};
2594
2595static ssize_t
2596state_show(struct md_rdev *rdev, char *page)
2597{
2598        char *sep = "";
2599        size_t len = 0;
2600
2601        if (test_bit(Faulty, &rdev->flags) ||
2602            rdev->badblocks.unacked_exist) {
2603                len+= sprintf(page+len, "%sfaulty",sep);
2604                sep = ",";
2605        }
2606        if (test_bit(In_sync, &rdev->flags)) {
2607                len += sprintf(page+len, "%sin_sync",sep);
2608                sep = ",";
2609        }
2610        if (test_bit(WriteMostly, &rdev->flags)) {
2611                len += sprintf(page+len, "%swrite_mostly",sep);
2612                sep = ",";
2613        }
2614        if (test_bit(Blocked, &rdev->flags) ||
2615            (rdev->badblocks.unacked_exist
2616             && !test_bit(Faulty, &rdev->flags))) {
2617                len += sprintf(page+len, "%sblocked", sep);
2618                sep = ",";
2619        }
2620        if (!test_bit(Faulty, &rdev->flags) &&
2621            !test_bit(In_sync, &rdev->flags)) {
2622                len += sprintf(page+len, "%sspare", sep);
2623                sep = ",";
2624        }
2625        if (test_bit(WriteErrorSeen, &rdev->flags)) {
2626                len += sprintf(page+len, "%swrite_error", sep);
2627                sep = ",";
2628        }
2629        if (test_bit(WantReplacement, &rdev->flags)) {
2630                len += sprintf(page+len, "%swant_replacement", sep);
2631                sep = ",";
2632        }
2633        if (test_bit(Replacement, &rdev->flags)) {
2634                len += sprintf(page+len, "%sreplacement", sep);
2635                sep = ",";
2636        }
2637
2638        return len+sprintf(page+len, "\n");
2639}
2640
2641static ssize_t
2642state_store(struct md_rdev *rdev, const char *buf, size_t len)
2643{
2644        /* can write
2645         *  faulty  - simulates an error
2646         *  remove  - disconnects the device
2647         *  writemostly - sets write_mostly
2648         *  -writemostly - clears write_mostly
2649         *  blocked - sets the Blocked flags
2650         *  -blocked - clears the Blocked and possibly simulates an error
2651         *  insync - sets Insync providing device isn't active
2652         *  write_error - sets WriteErrorSeen
2653         *  -write_error - clears WriteErrorSeen
2654         */
2655        int err = -EINVAL;
2656        if (cmd_match(buf, "faulty") && rdev->mddev->pers) {
2657                md_error(rdev->mddev, rdev);
2658                if (test_bit(Faulty, &rdev->flags))
2659                        err = 0;
2660                else
2661                        err = -EBUSY;
2662        } else if (cmd_match(buf, "remove")) {
2663                if (rdev->raid_disk >= 0)
2664                        err = -EBUSY;
2665                else {
2666                        struct mddev *mddev = rdev->mddev;
2667                        kick_rdev_from_array(rdev);
2668                        if (mddev->pers)
2669                                md_update_sb(mddev, 1);
2670                        md_new_event(mddev);
2671                        err = 0;
2672                }
2673        } else if (cmd_match(buf, "writemostly")) {
2674                set_bit(WriteMostly, &rdev->flags);
2675                err = 0;
2676        } else if (cmd_match(buf, "-writemostly")) {
2677                clear_bit(WriteMostly, &rdev->flags);
2678                err = 0;
2679        } else if (cmd_match(buf, "blocked")) {
2680                set_bit(Blocked, &rdev->flags);
2681                err = 0;
2682        } else if (cmd_match(buf, "-blocked")) {
2683                if (!test_bit(Faulty, &rdev->flags) &&
2684                    rdev->badblocks.unacked_exist) {
2685                        /* metadata handler doesn't understand badblocks,
2686                         * so we need to fail the device
2687                         */
2688                        md_error(rdev->mddev, rdev);
2689                }
2690                clear_bit(Blocked, &rdev->flags);
2691                clear_bit(BlockedBadBlocks, &rdev->flags);
2692                wake_up(&rdev->blocked_wait);
2693                set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
2694                md_wakeup_thread(rdev->mddev->thread);
2695
2696                err = 0;
2697        } else if (cmd_match(buf, "insync") && rdev->raid_disk == -1) {
2698                set_bit(In_sync, &rdev->flags);
2699                err = 0;
2700        } else if (cmd_match(buf, "write_error")) {
2701                set_bit(WriteErrorSeen, &rdev->flags);
2702                err = 0;
2703        } else if (cmd_match(buf, "-write_error")) {
2704                clear_bit(WriteErrorSeen, &rdev->flags);
2705                err = 0;
2706        } else if (cmd_match(buf, "want_replacement")) {
2707                /* Any non-spare device that is not a replacement can
2708                 * become want_replacement at any time, but we then need to
2709                 * check if recovery is needed.
2710                 */
2711                if (rdev->raid_disk >= 0 &&
2712                    !test_bit(Replacement, &rdev->flags))
2713                        set_bit(WantReplacement, &rdev->flags);
2714                set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
2715                md_wakeup_thread(rdev->mddev->thread);
2716                err = 0;
2717        } else if (cmd_match(buf, "-want_replacement")) {
2718                /* Clearing 'want_replacement' is always allowed.
2719                 * Once replacements starts it is too late though.
2720                 */
2721                err = 0;
2722                clear_bit(WantReplacement, &rdev->flags);
2723        } else if (cmd_match(buf, "replacement")) {
2724                /* Can only set a device as a replacement when array has not
2725                 * yet been started.  Once running, replacement is automatic
2726                 * from spares, or by assigning 'slot'.
2727                 */
2728                if (rdev->mddev->pers)
2729                        err = -EBUSY;
2730                else {
2731                        set_bit(Replacement, &rdev->flags);
2732                        err = 0;
2733                }
2734        } else if (cmd_match(buf, "-replacement")) {
2735                /* Similarly, can only clear Replacement before start */
2736                if (rdev->mddev->pers)
2737                        err = -EBUSY;
2738                else {
2739                        clear_bit(Replacement, &rdev->flags);
2740                        err = 0;
2741                }
2742        }
2743        if (!err)
2744                sysfs_notify_dirent_safe(rdev->sysfs_state);
2745        return err ? err : len;
2746}
2747static struct rdev_sysfs_entry rdev_state =
2748__ATTR(state, S_IRUGO|S_IWUSR, state_show, state_store);
2749
2750static ssize_t
2751errors_show(struct md_rdev *rdev, char *page)
2752{
2753        return sprintf(page, "%d\n", atomic_read(&rdev->corrected_errors));
2754}
2755
2756static ssize_t
2757errors_store(struct md_rdev *rdev, const char *buf, size_t len)
2758{
2759        char *e;
2760        unsigned long n = simple_strtoul(buf, &e, 10);
2761        if (*buf && (*e == 0 || *e == '\n')) {
2762                atomic_set(&rdev->corrected_errors, n);
2763                return len;
2764        }
2765        return -EINVAL;
2766}
2767static struct rdev_sysfs_entry rdev_errors =
2768__ATTR(errors, S_IRUGO|S_IWUSR, errors_show, errors_store);
2769
2770static ssize_t
2771slot_show(struct md_rdev *rdev, char *page)
2772{
2773        if (rdev->raid_disk < 0)
2774                return sprintf(page, "none\n");
2775        else
2776                return sprintf(page, "%d\n", rdev->raid_disk);
2777}
2778
2779static ssize_t
2780slot_store(struct md_rdev *rdev, const char *buf, size_t len)
2781{
2782        char *e;
2783        int err;
2784        int slot = simple_strtoul(buf, &e, 10);
2785        if (strncmp(buf, "none", 4)==0)
2786                slot = -1;
2787        else if (e==buf || (*e && *e!= '\n'))
2788                return -EINVAL;
2789        if (rdev->mddev->pers && slot == -1) {
2790                /* Setting 'slot' on an active array requires also
2791                 * updating the 'rd%d' link, and communicating
2792                 * with the personality with ->hot_*_disk.
2793                 * For now we only support removing
2794                 * failed/spare devices.  This normally happens automatically,
2795                 * but not when the metadata is externally managed.
2796                 */
2797                if (rdev->raid_disk == -1)
2798                        return -EEXIST;
2799                /* personality does all needed checks */
2800                if (rdev->mddev->pers->hot_remove_disk == NULL)
2801                        return -EINVAL;
2802                clear_bit(Blocked, &rdev->flags);
2803                remove_and_add_spares(rdev->mddev, rdev);
2804                if (rdev->raid_disk >= 0)
2805                        return -EBUSY;
2806                set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
2807                md_wakeup_thread(rdev->mddev->thread);
2808        } else if (rdev->mddev->pers) {
2809                /* Activating a spare .. or possibly reactivating
2810                 * if we ever get bitmaps working here.
2811                 */
2812
2813                if (rdev->raid_disk != -1)
2814                        return -EBUSY;
2815
2816                if (test_bit(MD_RECOVERY_RUNNING, &rdev->mddev->recovery))
2817                        return -EBUSY;
2818
2819                if (rdev->mddev->pers->hot_add_disk == NULL)
2820                        return -EINVAL;
2821
2822                if (slot >= rdev->mddev->raid_disks &&
2823                    slot >= rdev->mddev->raid_disks + rdev->mddev->delta_disks)
2824                        return -ENOSPC;
2825
2826                rdev->raid_disk = slot;
2827                if (test_bit(In_sync, &rdev->flags))
2828                        rdev->saved_raid_disk = slot;
2829                else
2830                        rdev->saved_raid_disk = -1;
2831                clear_bit(In_sync, &rdev->flags);
2832                err = rdev->mddev->pers->
2833                        hot_add_disk(rdev->mddev, rdev);
2834                if (err) {
2835                        rdev->raid_disk = -1;
2836                        return err;
2837                } else
2838                        sysfs_notify_dirent_safe(rdev->sysfs_state);
2839                if (sysfs_link_rdev(rdev->mddev, rdev))
2840                        /* failure here is OK */;
2841                /* don't wakeup anyone, leave that to userspace. */
2842        } else {
2843                if (slot >= rdev->mddev->raid_disks &&
2844                    slot >= rdev->mddev->raid_disks + rdev->mddev->delta_disks)
2845                        return -ENOSPC;
2846                rdev->raid_disk = slot;
2847                /* assume it is working */
2848                clear_bit(Faulty, &rdev->flags);
2849                clear_bit(WriteMostly, &rdev->flags);
2850                set_bit(In_sync, &rdev->flags);
2851                sysfs_notify_dirent_safe(rdev->sysfs_state);
2852        }
2853        return len;
2854}
2855
2856
2857static struct rdev_sysfs_entry rdev_slot =
2858__ATTR(slot, S_IRUGO|S_IWUSR, slot_show, slot_store);
2859
2860static ssize_t
2861offset_show(struct md_rdev *rdev, char *page)
2862{
2863        return sprintf(page, "%llu\n", (unsigned long long)rdev->data_offset);
2864}
2865
2866static ssize_t
2867offset_store(struct md_rdev *rdev, const char *buf, size_t len)
2868{
2869        unsigned long long offset;
2870        if (strict_strtoull(buf, 10, &offset) < 0)
2871                return -EINVAL;
2872        if (rdev->mddev->pers && rdev->raid_disk >= 0)
2873                return -EBUSY;
2874        if (rdev->sectors && rdev->mddev->external)
2875                /* Must set offset before size, so overlap checks
2876                 * can be sane */
2877                return -EBUSY;
2878        rdev->data_offset = offset;
2879        rdev->new_data_offset = offset;
2880        return len;
2881}
2882
2883static struct rdev_sysfs_entry rdev_offset =
2884__ATTR(offset, S_IRUGO|S_IWUSR, offset_show, offset_store);
2885
2886static ssize_t new_offset_show(struct md_rdev *rdev, char *page)
2887{
2888        return sprintf(page, "%llu\n",
2889                       (unsigned long long)rdev->new_data_offset);
2890}
2891
2892static ssize_t new_offset_store(struct md_rdev *rdev,
2893                                const char *buf, size_t len)
2894{
2895        unsigned long long new_offset;
2896        struct mddev *mddev = rdev->mddev;
2897
2898        if (strict_strtoull(buf, 10, &new_offset) < 0)
2899                return -EINVAL;
2900
2901        if (mddev->sync_thread)
2902                return -EBUSY;
2903        if (new_offset == rdev->data_offset)
2904                /* reset is always permitted */
2905                ;
2906        else if (new_offset > rdev->data_offset) {
2907                /* must not push array size beyond rdev_sectors */
2908                if (new_offset - rdev->data_offset
2909                    + mddev->dev_sectors > rdev->sectors)
2910                                return -E2BIG;
2911        }
2912        /* Metadata worries about other space details. */
2913
2914        /* decreasing the offset is inconsistent with a backwards
2915         * reshape.
2916         */
2917        if (new_offset < rdev->data_offset &&
2918            mddev->reshape_backwards)
2919                return -EINVAL;
2920        /* Increasing offset is inconsistent with forwards
2921         * reshape.  reshape_direction should be set to
2922         * 'backwards' first.
2923         */
2924        if (new_offset > rdev->data_offset &&
2925            !mddev->reshape_backwards)
2926                return -EINVAL;
2927
2928        if (mddev->pers && mddev->persistent &&
2929            !super_types[mddev->major_version]
2930            .allow_new_offset(rdev, new_offset))
2931                return -E2BIG;
2932        rdev->new_data_offset = new_offset;
2933        if (new_offset > rdev->data_offset)
2934                mddev->reshape_backwards = 1;
2935        else if (new_offset < rdev->data_offset)
2936                mddev->reshape_backwards = 0;
2937
2938        return len;
2939}
2940static struct rdev_sysfs_entry rdev_new_offset =
2941__ATTR(new_offset, S_IRUGO|S_IWUSR, new_offset_show, new_offset_store);
2942
2943static ssize_t
2944rdev_size_show(struct md_rdev *rdev, char *page)
2945{
2946        return sprintf(page, "%llu\n", (unsigned long long)rdev->sectors / 2);
2947}
2948
2949static int overlaps(sector_t s1, sector_t l1, sector_t s2, sector_t l2)
2950{
2951        /* check if two start/length pairs overlap */
2952        if (s1+l1 <= s2)
2953                return 0;
2954        if (s2+l2 <= s1)
2955                return 0;
2956        return 1;
2957}
2958
2959static int strict_blocks_to_sectors(const char *buf, sector_t *sectors)
2960{
2961        unsigned long long blocks;
2962        sector_t new;
2963
2964        if (strict_strtoull(buf, 10, &blocks) < 0)
2965                return -EINVAL;
2966
2967        if (blocks & 1ULL << (8 * sizeof(blocks) - 1))
2968                return -EINVAL; /* sector conversion overflow */
2969
2970        new = blocks * 2;
2971        if (new != blocks * 2)
2972                return -EINVAL; /* unsigned long long to sector_t overflow */
2973
2974        *sectors = new;
2975        return 0;
2976}
2977
2978static ssize_t
2979rdev_size_store(struct md_rdev *rdev, const char *buf, size_t len)
2980{
2981        struct mddev *my_mddev = rdev->mddev;
2982        sector_t oldsectors = rdev->sectors;
2983        sector_t sectors;
2984
2985        if (strict_blocks_to_sectors(buf, &sectors) < 0)
2986                return -EINVAL;
2987        if (rdev->data_offset != rdev->new_data_offset)
2988                return -EINVAL; /* too confusing */
2989        if (my_mddev->pers && rdev->raid_disk >= 0) {
2990                if (my_mddev->persistent) {
2991                        sectors = super_types[my_mddev->major_version].
2992                                rdev_size_change(rdev, sectors);
2993                        if (!sectors)
2994                                return -EBUSY;
2995                } else if (!sectors)
2996                        sectors = (i_size_read(rdev->bdev->bd_inode) >> 9) -
2997                                rdev->data_offset;
2998                if (!my_mddev->pers->resize)
2999                        /* Cannot change size for RAID0 or Linear etc */
3000                        return -EINVAL;
3001        }
3002        if (sectors < my_mddev->dev_sectors)
3003                return -EINVAL; /* component must fit device */
3004
3005        rdev->sectors = sectors;
3006        if (sectors > oldsectors && my_mddev->external) {
3007                /* need to check that all other rdevs with the same ->bdev
3008                 * do not overlap.  We need to unlock the mddev to avoid
3009                 * a deadlock.  We have already changed rdev->sectors, and if
3010                 * we have to change it back, we will have the lock again.
3011                 */
3012                struct mddev *mddev;
3013                int overlap = 0;
3014                struct list_head *tmp;
3015
3016                mddev_unlock(my_mddev);
3017                for_each_mddev(mddev, tmp) {
3018                        struct md_rdev *rdev2;
3019
3020                        mddev_lock(mddev);
3021                        rdev_for_each(rdev2, mddev)
3022                                if (rdev->bdev == rdev2->bdev &&
3023                                    rdev != rdev2 &&
3024                                    overlaps(rdev->data_offset, rdev->sectors,
3025                                             rdev2->data_offset,
3026                                             rdev2->sectors)) {
3027                                        overlap = 1;
3028                                        break;
3029                                }
3030                        mddev_unlock(mddev);
3031                        if (overlap) {
3032                                mddev_put(mddev);
3033                                break;
3034                        }
3035                }
3036                mddev_lock(my_mddev);
3037                if (overlap) {
3038                        /* Someone else could have slipped in a size
3039                         * change here, but doing so is just silly.
3040                         * We put oldsectors back because we *know* it is
3041                         * safe, and trust userspace not to race with
3042                         * itself
3043                         */
3044                        rdev->sectors = oldsectors;
3045                        return -EBUSY;
3046                }
3047        }
3048        return len;
3049}
3050
3051static struct rdev_sysfs_entry rdev_size =
3052__ATTR(size, S_IRUGO|S_IWUSR, rdev_size_show, rdev_size_store);
3053
3054
3055static ssize_t recovery_start_show(struct md_rdev *rdev, char *page)
3056{
3057        unsigned long long recovery_start = rdev->recovery_offset;
3058
3059        if (test_bit(In_sync, &rdev->flags) ||
3060            recovery_start == MaxSector)
3061                return sprintf(page, "none\n");
3062
3063        return sprintf(page, "%llu\n", recovery_start);
3064}
3065
3066static ssize_t recovery_start_store(struct md_rdev *rdev, const char *buf, size_t len)
3067{
3068        unsigned long long recovery_start;
3069
3070        if (cmd_match(buf, "none"))
3071                recovery_start = MaxSector;
3072        else if (strict_strtoull(buf, 10, &recovery_start))
3073                return -EINVAL;
3074
3075        if (rdev->mddev->pers &&
3076            rdev->raid_disk >= 0)
3077                return -EBUSY;
3078
3079        rdev->recovery_offset = recovery_start;
3080        if (recovery_start == MaxSector)
3081                set_bit(In_sync, &rdev->flags);
3082        else
3083                clear_bit(In_sync, &rdev->flags);
3084        return len;
3085}
3086
3087static struct rdev_sysfs_entry rdev_recovery_start =
3088__ATTR(recovery_start, S_IRUGO|S_IWUSR, recovery_start_show, recovery_start_store);
3089
3090
3091static ssize_t
3092badblocks_show(struct badblocks *bb, char *page, int unack);
3093static ssize_t
3094badblocks_store(struct badblocks *bb, const char *page, size_t len, int unack);
3095
3096static ssize_t bb_show(struct md_rdev *rdev, char *page)
3097{
3098        return badblocks_show(&rdev->badblocks, page, 0);
3099}
3100static ssize_t bb_store(struct md_rdev *rdev, const char *page, size_t len)
3101{
3102        int rv = badblocks_store(&rdev->badblocks, page, len, 0);
3103        /* Maybe that ack was all we needed */
3104        if (test_and_clear_bit(BlockedBadBlocks, &rdev->flags))
3105                wake_up(&rdev->blocked_wait);
3106        return rv;
3107}
3108static struct rdev_sysfs_entry rdev_bad_blocks =
3109__ATTR(bad_blocks, S_IRUGO|S_IWUSR, bb_show, bb_store);
3110
3111
3112static ssize_t ubb_show(struct md_rdev *rdev, char *page)
3113{
3114        return badblocks_show(&rdev->badblocks, page, 1);
3115}
3116static ssize_t ubb_store(struct md_rdev *rdev, const char *page, size_t len)
3117{
3118        return badblocks_store(&rdev->badblocks, page, len, 1);
3119}
3120static struct rdev_sysfs_entry rdev_unack_bad_blocks =
3121__ATTR(unacknowledged_bad_blocks, S_IRUGO|S_IWUSR, ubb_show, ubb_store);
3122
3123static struct attribute *rdev_default_attrs[] = {
3124        &rdev_state.attr,
3125        &rdev_errors.attr,
3126        &rdev_slot.attr,
3127        &rdev_offset.attr,
3128        &rdev_new_offset.attr,
3129        &rdev_size.attr,
3130        &rdev_recovery_start.attr,
3131        &rdev_bad_blocks.attr,
3132        &rdev_unack_bad_blocks.attr,
3133        NULL,
3134};
3135static ssize_t
3136rdev_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
3137{
3138        struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
3139        struct md_rdev *rdev = container_of(kobj, struct md_rdev, kobj);
3140        struct mddev *mddev = rdev->mddev;
3141        ssize_t rv;
3142
3143        if (!entry->show)
3144                return -EIO;
3145
3146        rv = mddev ? mddev_lock(mddev) : -EBUSY;
3147        if (!rv) {
3148                if (rdev->mddev == NULL)
3149                        rv = -EBUSY;
3150                else
3151                        rv = entry->show(rdev, page);
3152                mddev_unlock(mddev);
3153        }
3154        return rv;
3155}
3156
3157static ssize_t
3158rdev_attr_store(struct kobject *kobj, struct attribute *attr,
3159              const char *page, size_t length)
3160{
3161        struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
3162        struct md_rdev *rdev = container_of(kobj, struct md_rdev, kobj);
3163        ssize_t rv;
3164        struct mddev *mddev = rdev->mddev;
3165
3166        if (!entry->store)
3167                return -EIO;
3168        if (!capable(CAP_SYS_ADMIN))
3169                return -EACCES;
3170        rv = mddev ? mddev_lock(mddev): -EBUSY;
3171        if (!rv) {
3172                if (rdev->mddev == NULL)
3173                        rv = -EBUSY;
3174                else
3175                        rv = entry->store(rdev, page, length);
3176                mddev_unlock(mddev);
3177        }
3178        return rv;
3179}
3180
3181static void rdev_free(struct kobject *ko)
3182{
3183        struct md_rdev *rdev = container_of(ko, struct md_rdev, kobj);
3184        kfree(rdev);
3185}
3186static const struct sysfs_ops rdev_sysfs_ops = {
3187        .show           = rdev_attr_show,
3188        .store          = rdev_attr_store,
3189};
3190static struct kobj_type rdev_ktype = {
3191        .release        = rdev_free,
3192        .sysfs_ops      = &rdev_sysfs_ops,
3193        .default_attrs  = rdev_default_attrs,
3194};
3195
3196int md_rdev_init(struct md_rdev *rdev)
3197{
3198        rdev->desc_nr = -1;
3199        rdev->saved_raid_disk = -1;
3200        rdev->raid_disk = -1;
3201        rdev->flags = 0;
3202        rdev->data_offset = 0;
3203        rdev->new_data_offset = 0;
3204        rdev->sb_events = 0;
3205        rdev->last_read_error.tv_sec  = 0;
3206        rdev->last_read_error.tv_nsec = 0;
3207        rdev->sb_loaded = 0;
3208        rdev->bb_page = NULL;
3209        atomic_set(&rdev->nr_pending, 0);
3210        atomic_set(&rdev->read_errors, 0);
3211        atomic_set(&rdev->corrected_errors, 0);
3212
3213        INIT_LIST_HEAD(&rdev->same_set);
3214        init_waitqueue_head(&rdev->blocked_wait);
3215
3216        /* Add space to store bad block list.
3217         * This reserves the space even on arrays where it cannot
3218         * be used - I wonder if that matters
3219         */
3220        rdev->badblocks.count = 0;
3221        rdev->badblocks.shift = -1; /* disabled until explicitly enabled */
3222        rdev->badblocks.page = kmalloc(PAGE_SIZE, GFP_KERNEL);
3223        seqlock_init(&rdev->badblocks.lock);
3224        if (rdev->badblocks.page == NULL)
3225                return -ENOMEM;
3226
3227        return 0;
3228}
3229EXPORT_SYMBOL_GPL(md_rdev_init);
3230/*
3231 * Import a device. If 'super_format' >= 0, then sanity check the superblock
3232 *
3233 * mark the device faulty if:
3234 *
3235 *   - the device is nonexistent (zero size)
3236 *   - the device has no valid superblock
3237 *
3238 * a faulty rdev _never_ has rdev->sb set.
3239 */
3240static struct md_rdev *md_import_device(dev_t newdev, int super_format, int super_minor)
3241{
3242        char b[BDEVNAME_SIZE];
3243        int err;
3244        struct md_rdev *rdev;
3245        sector_t size;
3246
3247        rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
3248        if (!rdev) {
3249                printk(KERN_ERR "md: could not alloc mem for new device!\n");
3250                return ERR_PTR(-ENOMEM);
3251        }
3252
3253        err = md_rdev_init(rdev);
3254        if (err)
3255                goto abort_free;
3256        err = alloc_disk_sb(rdev);
3257        if (err)
3258                goto abort_free;
3259
3260        err = lock_rdev(rdev, newdev, super_format == -2);
3261        if (err)
3262                goto abort_free;
3263
3264        kobject_init(&rdev->kobj, &rdev_ktype);
3265
3266        size = i_size_read(rdev->bdev->bd_inode) >> BLOCK_SIZE_BITS;
3267        if (!size) {
3268                printk(KERN_WARNING 
3269                        "md: %s has zero or unknown size, marking faulty!\n",
3270                        bdevname(rdev->bdev,b));
3271                err = -EINVAL;
3272                goto abort_free;
3273        }
3274
3275        if (super_format >= 0) {
3276                err = super_types[super_format].
3277                        load_super(rdev, NULL, super_minor);
3278                if (err == -EINVAL) {
3279                        printk(KERN_WARNING
3280                                "md: %s does not have a valid v%d.%d "
3281                               "superblock, not importing!\n",
3282                                bdevname(rdev->bdev,b),
3283                               super_format, super_minor);
3284                        goto abort_free;
3285                }
3286                if (err < 0) {
3287                        printk(KERN_WARNING 
3288                                "md: could not read %s's sb, not importing!\n",
3289                                bdevname(rdev->bdev,b));
3290                        goto abort_free;
3291                }
3292        }
3293
3294        return rdev;
3295
3296abort_free:
3297        if (rdev->bdev)
3298                unlock_rdev(rdev);
3299        md_rdev_clear(rdev);
3300        kfree(rdev);
3301        return ERR_PTR(err);
3302}
3303
3304/*
3305 * Check a full RAID array for plausibility
3306 */
3307
3308
3309static void analyze_sbs(struct mddev * mddev)
3310{
3311        int i;
3312        struct md_rdev *rdev, *freshest, *tmp;
3313        char b[BDEVNAME_SIZE];
3314
3315        freshest = NULL;
3316        rdev_for_each_safe(rdev, tmp, mddev)
3317                switch (super_types[mddev->major_version].
3318                        load_super(rdev, freshest, mddev->minor_version)) {
3319                case 1:
3320                        freshest = rdev;
3321                        break;
3322                case 0:
3323                        break;
3324                default:
3325                        printk( KERN_ERR \
3326                                "md: fatal superblock inconsistency in %s"
3327                                " -- removing from array\n", 
3328                                bdevname(rdev->bdev,b));
3329                        kick_rdev_from_array(rdev);
3330                }
3331
3332
3333        super_types[mddev->major_version].
3334                validate_super(mddev, freshest);
3335
3336        i = 0;
3337        rdev_for_each_safe(rdev, tmp, mddev) {
3338                if (mddev->max_disks &&
3339                    (rdev->desc_nr >= mddev->max_disks ||
3340                     i > mddev->max_disks)) {
3341                        printk(KERN_WARNING
3342                               "md: %s: %s: only %d devices permitted\n",
3343                               mdname(mddev), bdevname(rdev->bdev, b),
3344                               mddev->max_disks);
3345                        kick_rdev_from_array(rdev);
3346                        continue;
3347                }
3348                if (rdev != freshest)
3349                        if (super_types[mddev->major_version].
3350                            validate_super(mddev, rdev)) {
3351                                printk(KERN_WARNING "md: kicking non-fresh %s"
3352                                        " from array!\n",
3353                                        bdevname(rdev->bdev,b));
3354                                kick_rdev_from_array(rdev);
3355                                continue;
3356                        }
3357                if (mddev->level == LEVEL_MULTIPATH) {
3358                        rdev->desc_nr = i++;
3359                        rdev->raid_disk = rdev->desc_nr;
3360                        set_bit(In_sync, &rdev->flags);
3361                } else if (rdev->raid_disk >= (mddev->raid_disks - min(0, mddev->delta_disks))) {
3362                        rdev->raid_disk = -1;
3363                        clear_bit(In_sync, &rdev->flags);
3364                }
3365        }
3366}
3367
3368/* Read a fixed-point number.
3369 * Numbers in sysfs attributes should be in "standard" units where
3370 * possible, so time should be in seconds.
3371 * However we internally use a a much smaller unit such as 
3372 * milliseconds or jiffies.
3373 * This function takes a decimal number with a possible fractional
3374 * component, and produces an integer which is the result of
3375 * multiplying that number by 10^'scale'.
3376 * all without any floating-point arithmetic.
3377 */
3378int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale)
3379{
3380        unsigned long result = 0;
3381        long decimals = -1;
3382        while (isdigit(*cp) || (*cp == '.' && decimals < 0)) {
3383                if (*cp == '.')
3384                        decimals = 0;
3385                else if (decimals < scale) {
3386                        unsigned int value;
3387                        value = *cp - '0';
3388                        result = result * 10 + value;
3389                        if (decimals >= 0)
3390                                decimals++;
3391                }
3392                cp++;
3393        }
3394        if (*cp == '\n')
3395                cp++;
3396        if (*cp)
3397                return -EINVAL;
3398        if (decimals < 0)
3399                decimals = 0;
3400        while (decimals < scale) {
3401                result *= 10;
3402                decimals ++;
3403        }
3404        *res = result;
3405        return 0;
3406}
3407
3408
3409static void md_safemode_timeout(unsigned long data);
3410
3411static ssize_t
3412safe_delay_show(struct mddev *mddev, char *page)
3413{
3414        int msec = (mddev->safemode_delay*1000)/HZ;
3415        return sprintf(page, "%d.%03d\n", msec/1000, msec%1000);
3416}
3417static ssize_t
3418safe_delay_store(struct mddev *mddev, const char *cbuf, size_t len)
3419{
3420        unsigned long msec;
3421
3422        if (strict_strtoul_scaled(cbuf, &msec, 3) < 0)
3423                return -EINVAL;
3424        if (msec == 0)
3425                mddev->safemode_delay = 0;
3426        else {
3427                unsigned long old_delay = mddev->safemode_delay;
3428                mddev->safemode_delay = (msec*HZ)/1000;
3429                if (mddev->safemode_delay == 0)
3430                        mddev->safemode_delay = 1;
3431                if (mddev->safemode_delay < old_delay)
3432                        md_safemode_timeout((unsigned long)mddev);
3433        }
3434        return len;
3435}
3436static struct md_sysfs_entry md_safe_delay =
3437__ATTR(safe_mode_delay, S_IRUGO|S_IWUSR,safe_delay_show, safe_delay_store);
3438
3439static ssize_t
3440level_show(struct mddev *mddev, char *page)
3441{
3442        struct md_personality *p = mddev->pers;
3443        if (p)
3444                return sprintf(page, "%s\n", p->name);
3445        else if (mddev->clevel[0])
3446                return sprintf(page, "%s\n", mddev->clevel);
3447        else if (mddev->level != LEVEL_NONE)
3448                return sprintf(page, "%d\n", mddev->level);
3449        else
3450                return 0;
3451}
3452
3453static ssize_t
3454level_store(struct mddev *mddev, const char *buf, size_t len)
3455{
3456        char clevel[16];
3457        ssize_t rv = len;
3458        struct md_personality *pers;
3459        long level;
3460        void *priv;
3461        struct md_rdev *rdev;
3462
3463        if (mddev->pers == NULL) {
3464                if (len == 0)
3465                        return 0;
3466                if (len >= sizeof(mddev->clevel))
3467                        return -ENOSPC;
3468                strncpy(mddev->clevel, buf, len);
3469                if (mddev->clevel[len-1] == '\n')
3470                        len--;
3471                mddev->clevel[len] = 0;
3472                mddev->level = LEVEL_NONE;
3473                return rv;
3474        }
3475
3476        /* request to change the personality.  Need to ensure:
3477         *  - array is not engaged in resync/recovery/reshape
3478         *  - old personality can be suspended
3479         *  - new personality will access other array.
3480         */
3481
3482        if (mddev->sync_thread ||
3483            mddev->reshape_position != MaxSector ||
3484            mddev->sysfs_active)
3485                return -EBUSY;
3486
3487        if (!mddev->pers->quiesce) {
3488                printk(KERN_WARNING "md: %s: %s does not support online personality change\n",
3489                       mdname(mddev), mddev->pers->name);
3490                return -EINVAL;
3491        }
3492
3493        /* Now find the new personality */
3494        if (len == 0 || len >= sizeof(clevel))
3495                return -EINVAL;
3496        strncpy(clevel, buf, len);
3497        if (clevel[len-1] == '\n')
3498                len--;
3499        clevel[len] = 0;
3500        if (strict_strtol(clevel, 10, &level))
3501                level = LEVEL_NONE;
3502
3503        if (request_module("md-%s", clevel) != 0)
3504                request_module("md-level-%s", clevel);
3505        spin_lock(&pers_lock);
3506        pers = find_pers(level, clevel);
3507        if (!pers || !try_module_get(pers->owner)) {
3508                spin_unlock(&pers_lock);
3509                printk(KERN_WARNING "md: personality %s not loaded\n", clevel);
3510                return -EINVAL;
3511        }
3512        spin_unlock(&pers_lock);
3513
3514        if (pers == mddev->pers) {
3515                /* Nothing to do! */
3516                module_put(pers->owner);
3517                return rv;
3518        }
3519        if (!pers->takeover) {
3520                module_put(pers->owner);
3521                printk(KERN_WARNING "md: %s: %s does not support personality takeover\n",
3522                       mdname(mddev), clevel);
3523                return -EINVAL;
3524        }
3525
3526        rdev_for_each(rdev, mddev)
3527                rdev->new_raid_disk = rdev->raid_disk;
3528
3529        /* ->takeover must set new_* and/or delta_disks
3530         * if it succeeds, and may set them when it fails.
3531         */
3532        priv = pers->takeover(mddev);
3533        if (IS_ERR(priv)) {
3534                mddev->new_level = mddev->level;
3535                mddev->new_layout = mddev->layout;
3536                mddev->new_chunk_sectors = mddev->chunk_sectors;
3537                mddev->raid_disks -= mddev->delta_disks;
3538                mddev->delta_disks = 0;
3539                mddev->reshape_backwards = 0;
3540                module_put(pers->owner);
3541                printk(KERN_WARNING "md: %s: %s would not accept array\n",
3542                       mdname(mddev), clevel);
3543                return PTR_ERR(priv);
3544        }
3545
3546        /* Looks like we have a winner */
3547        mddev_suspend(mddev);
3548        mddev->pers->stop(mddev);
3549        
3550        if (mddev->pers->sync_request == NULL &&
3551            pers->sync_request != NULL) {
3552                /* need to add the md_redundancy_group */
3553                if (sysfs_create_group(&mddev->kobj, &md_redundancy_group))
3554                        printk(KERN_WARNING
3555                               "md: cannot register extra attributes for %s\n",
3556                               mdname(mddev));
3557                mddev->sysfs_action = sysfs_get_dirent(mddev->kobj.sd, NULL, "sync_action");
3558        }               
3559        if (mddev->pers->sync_request != NULL &&
3560            pers->sync_request == NULL) {
3561                /* need to remove the md_redundancy_group */
3562                if (mddev->to_remove == NULL)
3563                        mddev->to_remove = &md_redundancy_group;
3564        }
3565
3566        if (mddev->pers->sync_request == NULL &&
3567            mddev->external) {
3568                /* We are converting from a no-redundancy array
3569                 * to a redundancy array and metadata is managed
3570                 * externally so we need to be sure that writes
3571                 * won't block due to a need to transition
3572                 *      clean->dirty
3573                 * until external management is started.
3574                 */
3575                mddev->in_sync = 0;
3576                mddev->safemode_delay = 0;
3577                mddev->safemode = 0;
3578        }
3579
3580        rdev_for_each(rdev, mddev) {
3581                if (rdev->raid_disk < 0)
3582                        continue;
3583                if (rdev->new_raid_disk >= mddev->raid_disks)
3584                        rdev->new_raid_disk = -1;
3585                if (rdev->new_raid_disk == rdev->raid_disk)
3586                        continue;
3587                sysfs_unlink_rdev(mddev, rdev);
3588        }
3589        rdev_for_each(rdev, mddev) {
3590                if (rdev->raid_disk < 0)
3591                        continue;
3592                if (rdev->new_raid_disk == rdev->raid_disk)
3593                        continue;
3594                rdev->raid_disk = rdev->new_raid_disk;
3595                if (rdev->raid_disk < 0)
3596                        clear_bit(In_sync, &rdev->flags);
3597                else {
3598                        if (sysfs_link_rdev(mddev, rdev))
3599                                printk(KERN_WARNING "md: cannot register rd%d"
3600                                       " for %s after level change\n",
3601                                       rdev->raid_disk, mdname(mddev));
3602                }
3603        }
3604
3605        module_put(mddev->pers->owner);
3606        mddev->pers = pers;
3607        mddev->private = priv;
3608        strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
3609        mddev->level = mddev->new_level;
3610        mddev->layout = mddev->new_layout;
3611        mddev->chunk_sectors = mddev->new_chunk_sectors;
3612        mddev->delta_disks = 0;
3613        mddev->reshape_backwards = 0;
3614        mddev->degraded = 0;
3615        if (mddev->pers->sync_request == NULL) {
3616                /* this is now an array without redundancy, so
3617                 * it must always be in_sync
3618                 */
3619                mddev->in_sync = 1;
3620                del_timer_sync(&mddev->safemode_timer);
3621        }
3622        pers->run(mddev);
3623        set_bit(MD_CHANGE_DEVS, &mddev->flags);
3624        mddev_resume(mddev);
3625        sysfs_notify(&mddev->kobj, NULL, "level");
3626        md_new_event(mddev);
3627        return rv;
3628}
3629
3630static struct md_sysfs_entry md_level =
3631__ATTR(level, S_IRUGO|S_IWUSR, level_show, level_store);
3632
3633
3634static ssize_t
3635layout_show(struct mddev *mddev, char *page)
3636{
3637        /* just a number, not meaningful for all levels */
3638        if (mddev->reshape_position != MaxSector &&
3639            mddev->layout != mddev->new_layout)
3640                return sprintf(page, "%d (%d)\n",
3641                               mddev->new_layout, mddev->layout);
3642        return sprintf(page, "%d\n", mddev->layout);
3643}
3644
3645static ssize_t
3646layout_store(struct mddev *mddev, const char *buf, size_t len)
3647{
3648        char *e;
3649        unsigned long n = simple_strtoul(buf, &e, 10);
3650
3651        if (!*buf || (*e && *e != '\n'))
3652                return -EINVAL;
3653
3654        if (mddev->pers) {
3655                int err;
3656                if (mddev->pers->check_reshape == NULL)
3657                        return -EBUSY;
3658                mddev->new_layout = n;
3659                err = mddev->pers->check_reshape(mddev);
3660                if (err) {
3661                        mddev->new_layout = mddev->layout;
3662                        return err;
3663                }
3664        } else {
3665                mddev->new_layout = n;
3666                if (mddev->reshape_position == MaxSector)
3667                        mddev->layout = n;
3668        }
3669        return len;
3670}
3671static struct md_sysfs_entry md_layout =
3672__ATTR(layout, S_IRUGO|S_IWUSR, layout_show, layout_store);
3673
3674
3675static ssize_t
3676raid_disks_show(struct mddev *mddev, char *page)
3677{
3678        if (mddev->raid_disks == 0)
3679                return 0;
3680        if (mddev->reshape_position != MaxSector &&
3681            mddev->delta_disks != 0)
3682                return sprintf(page, "%d (%d)\n", mddev->raid_disks,
3683                               mddev->raid_disks - mddev->delta_disks);
3684        return sprintf(page, "%d\n", mddev->raid_disks);
3685}
3686
3687static int update_raid_disks(struct mddev *mddev, int raid_disks);
3688
3689static ssize_t
3690raid_disks_store(struct mddev *mddev, const char *buf, size_t len)
3691{
3692        char *e;
3693        int rv = 0;
3694        unsigned long n = simple_strtoul(buf, &e, 10);
3695
3696        if (!*buf || (*e && *e != '\n'))
3697                return -EINVAL;
3698
3699        if (mddev->pers)
3700                rv = update_raid_disks(mddev, n);
3701        else if (mddev->reshape_position != MaxSector) {
3702                struct md_rdev *rdev;
3703                int olddisks = mddev->raid_disks - mddev->delta_disks;
3704
3705                rdev_for_each(rdev, mddev) {
3706                        if (olddisks < n &&
3707                            rdev->data_offset < rdev->new_data_offset)
3708                                return -EINVAL;
3709                        if (olddisks > n &&
3710                            rdev->data_offset > rdev->new_data_offset)
3711                                return -EINVAL;
3712                }
3713                mddev->delta_disks = n - olddisks;
3714                mddev->raid_disks = n;
3715                mddev->reshape_backwards = (mddev->delta_disks < 0);
3716        } else
3717                mddev->raid_disks = n;
3718        return rv ? rv : len;
3719}
3720static struct md_sysfs_entry md_raid_disks =
3721__ATTR(raid_disks, S_IRUGO|S_IWUSR, raid_disks_show, raid_disks_store);
3722
3723static ssize_t
3724chunk_size_show(struct mddev *mddev, char *page)
3725{
3726        if (mddev->reshape_position != MaxSector &&
3727            mddev->chunk_sectors != mddev->new_chunk_sectors)
3728                return sprintf(page, "%d (%d)\n",
3729                               mddev->new_chunk_sectors << 9,
3730                               mddev->chunk_sectors << 9);
3731        return sprintf(page, "%d\n", mddev->chunk_sectors << 9);
3732}
3733
3734static ssize_t
3735chunk_size_store(struct mddev *mddev, const char *buf, size_t len)
3736{
3737        char *e;
3738        unsigned long n = simple_strtoul(buf, &e, 10);
3739
3740        if (!*buf || (*e && *e != '\n'))
3741                return -EINVAL;
3742
3743        if (mddev->pers) {
3744                int err;
3745                if (mddev->pers->check_reshape == NULL)
3746                        return -EBUSY;
3747                mddev->new_chunk_sectors = n >> 9;
3748                err = mddev->pers->check_reshape(mddev);
3749                if (err) {
3750                        mddev->new_chunk_sectors = mddev->chunk_sectors;
3751                        return err;
3752                }
3753        } else {
3754                mddev->new_chunk_sectors = n >> 9;
3755                if (mddev->reshape_position == MaxSector)
3756                        mddev->chunk_sectors = n >> 9;
3757        }
3758        return len;
3759}
3760static struct md_sysfs_entry md_chunk_size =
3761__ATTR(chunk_size, S_IRUGO|S_IWUSR, chunk_size_show, chunk_size_store);
3762
3763static ssize_t
3764resync_start_show(struct mddev *mddev, char *page)
3765{
3766        if (mddev->recovery_cp == MaxSector)
3767                return sprintf(page, "none\n");
3768        return sprintf(page, "%llu\n", (unsigned long long)mddev->recovery_cp);
3769}
3770
3771static ssize_t
3772resync_start_store(struct mddev *mddev, const char *buf, size_t len)
3773{
3774        char *e;
3775        unsigned long long n = simple_strtoull(buf, &e, 10);
3776
3777        if (mddev->pers && !test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
3778                return -EBUSY;
3779        if (cmd_match(buf, "none"))
3780                n = MaxSector;
3781        else if (!*buf || (*e && *e != '\n'))
3782                return -EINVAL;
3783
3784        mddev->recovery_cp = n;
3785        if (mddev->pers)
3786                set_bit(MD_CHANGE_CLEAN, &mddev->flags);
3787        return len;
3788}
3789static struct md_sysfs_entry md_resync_start =
3790__ATTR(resync_start, S_IRUGO|S_IWUSR, resync_start_show, resync_start_store);
3791
3792/*
3793 * The array state can be:
3794 *
3795 * clear
3796 *     No devices, no size, no level
3797 *     Equivalent to STOP_ARRAY ioctl
3798 * inactive
3799 *     May have some settings, but array is not active
3800 *        all IO results in error
3801 *     When written, doesn't tear down array, but just stops it
3802 * suspended (not supported yet)
3803 *     All IO requests will block. The array can be reconfigured.
3804 *     Writing this, if accepted, will block until array is quiescent
3805 * readonly
3806 *     no resync can happen.  no superblocks get written.
3807 *     write requests fail
3808 * read-auto
3809 *     like readonly, but behaves like 'clean' on a write request.
3810 *
3811 * clean - no pending writes, but otherwise active.
3812 *     When written to inactive array, starts without resync
3813 *     If a write request arrives then
3814 *       if metadata is known, mark 'dirty' and switch to 'active'.
3815 *       if not known, block and switch to write-pending
3816 *     If written to an active array that has pending writes, then fails.
3817 * active
3818 *     fully active: IO and resync can be happening.
3819 *     When written to inactive array, starts with resync
3820 *
3821 * write-pending
3822 *     clean, but writes are blocked waiting for 'active' to be written.
3823 *
3824 * active-idle
3825 *     like active, but no writes have been seen for a while (100msec).
3826 *
3827 */
3828enum array_state { clear, inactive, suspended, readonly, read_auto, clean, active,
3829                   write_pending, active_idle, bad_word};
3830static char *array_states[] = {
3831        "clear", "inactive", "suspended", "readonly", "read-auto", "clean", "active",
3832        "write-pending", "active-idle", NULL };
3833
3834static int match_word(const char *word, char **list)
3835{
3836        int n;
3837        for (n=0; list[n]; n++)
3838                if (cmd_match(word, list[n]))
3839                        break;
3840        return n;
3841}
3842
3843static ssize_t
3844array_state_show(struct mddev *mddev, char *page)
3845{
3846        enum array_state st = inactive;
3847
3848        if (mddev->pers)
3849                switch(mddev->ro) {
3850                case 1:
3851                        st = readonly;
3852                        break;
3853                case 2:
3854                        st = read_auto;
3855                        break;
3856                case 0:
3857                        if (mddev->in_sync)
3858                                st = clean;
3859                        else if (test_bit(MD_CHANGE_PENDING, &mddev->flags))
3860                                st = write_pending;
3861                        else if (mddev->safemode)
3862                                st = active_idle;
3863                        else
3864                                st = active;
3865                }
3866        else {
3867                if (list_empty(&mddev->disks) &&
3868                    mddev->raid_disks == 0 &&
3869                    mddev->dev_sectors == 0)
3870                        st = clear;
3871                else
3872                        st = inactive;
3873        }
3874        return sprintf(page, "%s\n", array_states[st]);
3875}
3876
3877static int do_md_stop(struct mddev * mddev, int ro, struct block_device *bdev);
3878static int md_set_readonly(struct mddev * mddev, struct block_device *bdev);
3879static int do_md_run(struct mddev * mddev);
3880static int restart_array(struct mddev *mddev);
3881
3882static ssize_t
3883array_state_store(struct mddev *mddev, const char *buf, size_t len)
3884{
3885        int err = -EINVAL;
3886        enum array_state st = match_word(buf, array_states);
3887        switch(st) {
3888        case bad_word:
3889                break;
3890        case clear:
3891                /* stopping an active array */
3892                err = do_md_stop(mddev, 0, NULL);
3893                break;
3894        case inactive:
3895                /* stopping an active array */
3896                if (mddev->pers)
3897                        err = do_md_stop(mddev, 2, NULL);
3898                else
3899                        err = 0; /* already inactive */
3900                break;
3901        case suspended:
3902                break; /* not supported yet */
3903        case readonly:
3904                if (mddev->pers)
3905                        err = md_set_readonly(mddev, NULL);
3906                else {
3907                        mddev->ro = 1;
3908                        set_disk_ro(mddev->gendisk, 1);
3909                        err = do_md_run(mddev);
3910                }
3911                break;
3912        case read_auto:
3913                if (mddev->pers) {
3914                        if (mddev->ro == 0)
3915                                err = md_set_readonly(mddev, NULL);
3916                        else if (mddev->ro == 1)
3917                                err = restart_array(mddev);
3918                        if (err == 0) {
3919                                mddev->ro = 2;
3920                                set_disk_ro(mddev->gendisk, 0);
3921                        }
3922                } else {
3923                        mddev->ro = 2;
3924                        err = do_md_run(mddev);
3925                }
3926                break;
3927        case clean:
3928                if (mddev->pers) {
3929                        restart_array(mddev);
3930                        spin_lock_irq(&mddev->write_lock);
3931                        if (atomic_read(&mddev->writes_pending) == 0) {
3932                                if (mddev->in_sync == 0) {
3933                                        mddev->in_sync = 1;
3934                                        if (mddev->safemode == 1)
3935                                                mddev->safemode = 0;
3936                                        set_bit(MD_CHANGE_CLEAN, &mddev->flags);
3937                                }
3938                                err = 0;
3939                        } else
3940                                err = -EBUSY;
3941                        spin_unlock_irq(&mddev->write_lock);
3942                } else
3943                        err = -EINVAL;
3944                break;
3945        case active:
3946                if (mddev->pers) {
3947                        restart_array(mddev);
3948                        clear_bit(MD_CHANGE_PENDING, &mddev->flags);
3949                        wake_up(&mddev->sb_wait);
3950                        err = 0;
3951                } else {
3952                        mddev->ro = 0;
3953                        set_disk_ro(mddev->gendisk, 0);
3954                        err = do_md_run(mddev);
3955                }
3956                break;
3957        case write_pending:
3958        case active_idle:
3959                /* these cannot be set */
3960                break;
3961        }
3962        if (err)
3963                return err;
3964        else {
3965                if (mddev->hold_active == UNTIL_IOCTL)
3966                        mddev->hold_active = 0;
3967                sysfs_notify_dirent_safe(mddev->sysfs_state);
3968                return len;
3969        }
3970}
3971static struct md_sysfs_entry md_array_state =
3972__ATTR(array_state, S_IRUGO|S_IWUSR, array_state_show, array_state_store);
3973
3974static ssize_t
3975max_corrected_read_errors_show(struct mddev *mddev, char *page) {
3976        return sprintf(page, "%d\n",
3977                       atomic_read(&mddev->max_corr_read_errors));
3978}
3979
3980static ssize_t
3981max_corrected_read_errors_store(struct mddev *mddev, const char *buf, size_t len)
3982{
3983        char *e;
3984        unsigned long n = simple_strtoul(buf, &e, 10);
3985
3986        if (*buf && (*e == 0 || *e == '\n')) {
3987                atomic_set(&mddev->max_corr_read_errors, n);
3988                return len;
3989        }
3990        return -EINVAL;
3991}
3992
3993static struct md_sysfs_entry max_corr_read_errors =
3994__ATTR(max_read_errors, S_IRUGO|S_IWUSR, max_corrected_read_errors_show,
3995        max_corrected_read_errors_store);
3996
3997static ssize_t
3998null_show(struct mddev *mddev, char *page)
3999{
4000        return -EINVAL;
4001}
4002
4003static ssize_t
4004new_dev_store(struct mddev *mddev, const char *buf, size_t len)
4005{
4006        /* buf must be %d:%d\n? giving major and minor numbers */
4007        /* The new device is added to the array.
4008         * If the array has a persistent superblock, we read the
4009         * superblock to initialise info and check validity.
4010         * Otherwise, only checking done is that in bind_rdev_to_array,
4011         * which mainly checks size.
4012         */
4013        char *e;
4014        int major = simple_strtoul(buf, &e, 10);
4015        int minor;
4016        dev_t dev;
4017        struct md_rdev *rdev;
4018        int err;
4019
4020        if (!*buf || *e != ':' || !e[1] || e[1] == '\n')
4021                return -EINVAL;
4022        minor = simple_strtoul(e+1, &e, 10);
4023        if (*e && *e != '\n')
4024                return -EINVAL;
4025        dev = MKDEV(major, minor);
4026        if (major != MAJOR(dev) ||
4027            minor != MINOR(dev))
4028                return -EOVERFLOW;
4029
4030
4031        if (mddev->persistent) {
4032                rdev = md_import_device(dev, mddev->major_version,
4033                                        mddev->minor_version);
4034                if (!IS_ERR(rdev) && !list_empty(&mddev->disks)) {
4035                        struct md_rdev *rdev0
4036                                = list_entry(mddev->disks.next,
4037                                             struct md_rdev, same_set);
4038                        err = super_types[mddev->major_version]
4039                                .load_super(rdev, rdev0, mddev->minor_version);
4040                        if (err < 0)
4041                                goto out;
4042                }
4043        } else if (mddev->external)
4044                rdev = md_import_device(dev, -2, -1);
4045        else
4046                rdev = md_import_device(dev, -1, -1);
4047
4048        if (IS_ERR(rdev))
4049                return PTR_ERR(rdev);
4050        err = bind_rdev_to_array(rdev, mddev);
4051 out:
4052        if (err)
4053                export_rdev(rdev);
4054        return err ? err : len;
4055}
4056
4057static struct md_sysfs_entry md_new_device =
4058__ATTR(new_dev, S_IWUSR, null_show, new_dev_store);
4059
4060static ssize_t
4061bitmap_store(struct mddev *mddev, const char *buf, size_t len)
4062{
4063        char *end;
4064        unsigned long chunk, end_chunk;
4065
4066        if (!mddev->bitmap)
4067                goto out;
4068        /* buf should be <chunk> <chunk> ... or <chunk>-<chunk> ... (range) */
4069        while (*buf) {
4070                chunk = end_chunk = simple_strtoul(buf, &end, 0);
4071                if (buf == end) break;
4072                if (*end == '-') { /* range */
4073                        buf = end + 1;
4074                        end_chunk = simple_strtoul(buf, &end, 0);
4075                        if (buf == end) break;
4076                }
4077                if (*end && !isspace(*end)) break;
4078                bitmap_dirty_bits(mddev->bitmap, chunk, end_chunk);
4079                buf = skip_spaces(end);
4080        }
4081        bitmap_unplug(mddev->bitmap); /* flush the bits to disk */
4082out:
4083        return len;
4084}
4085
4086static struct md_sysfs_entry md_bitmap =
4087__ATTR(bitmap_set_bits, S_IWUSR, null_show, bitmap_store);
4088
4089static ssize_t
4090size_show(struct mddev *mddev, char *page)
4091{
4092        return sprintf(page, "%llu\n",
4093                (unsigned long long)mddev->dev_sectors / 2);
4094}
4095
4096static int update_size(struct mddev *mddev, sector_t num_sectors);
4097
4098static ssize_t
4099size_store(struct mddev *mddev, const char *buf, size_t len)
4100{
4101        /* If array is inactive, we can reduce the component size, but
4102         * not increase it (except from 0).
4103         * If array is active, we can try an on-line resize
4104         */
4105        sector_t sectors;
4106        int err = strict_blocks_to_sectors(buf, &sectors);
4107
4108        if (err < 0)
4109                return err;
4110        if (mddev->pers) {
4111                err = update_size(mddev, sectors);
4112                md_update_sb(mddev, 1);
4113        } else {
4114                if (mddev->dev_sectors == 0 ||
4115                    mddev->dev_sectors > sectors)
4116                        mddev->dev_sectors = sectors;
4117                else
4118                        err = -ENOSPC;
4119        }
4120        return err ? err : len;
4121}
4122
4123static struct md_sysfs_entry md_size =
4124__ATTR(component_size, S_IRUGO|S_IWUSR, size_show, size_store);
4125
4126
4127/* Metadata version.
4128 * This is one of
4129 *   'none' for arrays with no metadata (good luck...)
4130 *   'external' for arrays with externally managed metadata,
4131 * or N.M for internally known formats
4132 */
4133static ssize_t
4134metadata_show(struct mddev *mddev, char *page)
4135{
4136        if (mddev->persistent)
4137                return sprintf(page, "%d.%d\n",
4138                               mddev->major_version, mddev->minor_version);
4139        else if (mddev->external)
4140                return sprintf(page, "external:%s\n", mddev->metadata_type);
4141        else
4142                return sprintf(page, "none\n");
4143}
4144
4145static ssize_t
4146metadata_store(struct mddev *mddev, const char *buf, size_t len)
4147{
4148        int major, minor;
4149        char *e;
4150        /* Changing the details of 'external' metadata is
4151         * always permitted.  Otherwise there must be
4152         * no devices attached to the array.
4153         */
4154        if (mddev->external && strncmp(buf, "external:", 9) == 0)
4155                ;
4156        else if (!list_empty(&mddev->disks))
4157                return -EBUSY;
4158
4159        if (cmd_match(buf, "none")) {
4160                mddev->persistent = 0;
4161                mddev->external = 0;
4162                mddev->major_version = 0;
4163                mddev->minor_version = 90;
4164                return len;
4165        }
4166        if (strncmp(buf, "external:", 9) == 0) {
4167                size_t namelen = len-9;
4168                if (namelen >= sizeof(mddev->metadata_type))
4169                        namelen = sizeof(mddev->metadata_type)-1;
4170                strncpy(mddev->metadata_type, buf+9, namelen);
4171                mddev->metadata_type[namelen] = 0;
4172                if (namelen && mddev->metadata_type[namelen-1] == '\n')
4173                        mddev->metadata_type[--namelen] = 0;
4174                mddev->persistent = 0;
4175                mddev->external = 1;
4176                mddev->major_version = 0;
4177                mddev->minor_version = 90;
4178                return len;
4179        }
4180        major = simple_strtoul(buf, &e, 10);
4181        if (e==buf || *e != '.')
4182                return -EINVAL;
4183        buf = e+1;
4184        minor = simple_strtoul(buf, &e, 10);
4185        if (e==buf || (*e && *e != '\n') )
4186                return -EINVAL;
4187        if (major >= ARRAY_SIZE(super_types) || super_types[major].name == NULL)
4188                return -ENOENT;
4189        mddev->major_version = major;
4190        mddev->minor_version = minor;
4191        mddev->persistent = 1;
4192        mddev->external = 0;
4193        return len;
4194}
4195
4196static struct md_sysfs_entry md_metadata =
4197__ATTR(metadata_version, S_IRUGO|S_IWUSR, metadata_show, metadata_store);
4198
4199static ssize_t
4200action_show(struct mddev *mddev, char *page)
4201{
4202        char *type = "idle";
4203        if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
4204                type = "frozen";
4205        else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
4206            (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) {
4207                if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
4208                        type = "reshape";
4209                else if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
4210                        if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
4211                                type = "resync";
4212                        else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
4213                                type = "check";
4214                        else
4215                                type = "repair";
4216                } else if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery))
4217                        type = "recover";
4218        }
4219        return sprintf(page, "%s\n", type);
4220}
4221
4222static ssize_t
4223action_store(struct mddev *mddev, const char *page, size_t len)
4224{
4225        if (!mddev->pers || !mddev->pers->sync_request)
4226                return -EINVAL;
4227
4228        if (cmd_match(page, "frozen"))
4229                set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4230        else
4231                clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4232
4233        if (cmd_match(page, "idle") || cmd_match(page, "frozen")) {
4234                if (mddev->sync_thread) {
4235                        set_bit(MD_RECOVERY_INTR, &mddev->recovery);
4236                        md_reap_sync_thread(mddev);
4237                }
4238        } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
4239                   test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
4240                return -EBUSY;
4241        else if (cmd_match(page, "resync"))
4242                set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4243        else if (cmd_match(page, "recover")) {
4244                set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
4245                set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4246        } else if (cmd_match(page, "reshape")) {
4247                int err;
4248                if (mddev->pers->start_reshape == NULL)
4249                        return -EINVAL;
4250                err = mddev->pers->start_reshape(mddev);
4251                if (err)
4252                        return err;
4253                sysfs_notify(&mddev->kobj, NULL, "degraded");
4254        } else {
4255                if (cmd_match(page, "check"))
4256                        set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
4257                else if (!cmd_match(page, "repair"))
4258                        return -EINVAL;
4259                set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
4260                set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
4261        }
4262        if (mddev->ro == 2) {
4263                /* A write to sync_action is enough to justify
4264                 * canceling read-auto mode
4265                 */
4266                mddev->ro = 0;
4267                md_wakeup_thread(mddev->sync_thread);
4268        }
4269        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4270        md_wakeup_thread(mddev->thread);
4271        sysfs_notify_dirent_safe(mddev->sysfs_action);
4272        return len;
4273}
4274
4275static ssize_t
4276mismatch_cnt_show(struct mddev *mddev, char *page)
4277{
4278        return sprintf(page, "%llu\n",
4279                       (unsigned long long)
4280                       atomic64_read(&mddev->resync_mismatches));
4281}
4282
4283static struct md_sysfs_entry md_scan_mode =
4284__ATTR(sync_action, S_IRUGO|S_IWUSR, action_show, action_store);
4285
4286
4287static struct md_sysfs_entry md_mismatches = __ATTR_RO(mismatch_cnt);
4288
4289static ssize_t
4290sync_min_show(struct mddev *mddev, char *page)
4291{
4292        return sprintf(page, "%d (%s)\n", speed_min(mddev),
4293                       mddev->sync_speed_min ? "local": "system");
4294}
4295
4296static ssize_t
4297sync_min_store(struct mddev *mddev, const char *buf, size_t len)
4298{
4299        int min;
4300        char *e;
4301        if (strncmp(buf, "system", 6)==0) {
4302                mddev->sync_speed_min = 0;
4303                return len;
4304        }
4305        min = simple_strtoul(buf, &e, 10);
4306        if (buf == e || (*e && *e != '\n') || min <= 0)
4307                return -EINVAL;
4308        mddev->sync_speed_min = min;
4309        return len;
4310}
4311
4312static struct md_sysfs_entry md_sync_min =
4313__ATTR(sync_speed_min, S_IRUGO|S_IWUSR, sync_min_show, sync_min_store);
4314
4315static ssize_t
4316sync_max_show(struct mddev *mddev, char *page)
4317{
4318        return sprintf(page, "%d (%s)\n", speed_max(mddev),
4319                       mddev->sync_speed_max ? "local": "system");
4320}
4321
4322static ssize_t
4323sync_max_store(struct mddev *mddev, const char *buf, size_t len)
4324{
4325        int max;
4326        char *e;
4327        if (strncmp(buf, "system", 6)==0) {
4328                mddev->sync_speed_max = 0;
4329                return len;
4330        }
4331        max = simple_strtoul(buf, &e, 10);
4332        if (buf == e || (*e && *e != '\n') || max <= 0)
4333                return -EINVAL;
4334        mddev->sync_speed_max = max;
4335        return len;
4336}
4337
4338static struct md_sysfs_entry md_sync_max =
4339__ATTR(sync_speed_max, S_IRUGO|S_IWUSR, sync_max_show, sync_max_store);
4340
4341static ssize_t
4342degraded_show(struct mddev *mddev, char *page)
4343{
4344        return sprintf(page, "%d\n", mddev->degraded);
4345}
4346static struct md_sysfs_entry md_degraded = __ATTR_RO(degraded);
4347
4348static ssize_t
4349sync_force_parallel_show(struct mddev *mddev, char *page)
4350{
4351        return sprintf(page, "%d\n", mddev->parallel_resync);
4352}
4353
4354static ssize_t
4355sync_force_parallel_store(struct mddev *mddev, const char *buf, size_t len)
4356{
4357        long n;
4358
4359        if (strict_strtol(buf, 10, &n))
4360                return -EINVAL;
4361
4362        if (n != 0 && n != 1)
4363                return -EINVAL;
4364
4365        mddev->parallel_resync = n;
4366
4367        if (mddev->sync_thread)
4368                wake_up(&resync_wait);
4369
4370        return len;
4371}
4372
4373/* force parallel resync, even with shared block devices */
4374static struct md_sysfs_entry md_sync_force_parallel =
4375__ATTR(sync_force_parallel, S_IRUGO|S_IWUSR,
4376       sync_force_parallel_show, sync_force_parallel_store);
4377
4378static ssize_t
4379sync_speed_show(struct mddev *mddev, char *page)
4380{
4381        unsigned long resync, dt, db;
4382        if (mddev->curr_resync == 0)
4383                return sprintf(page, "none\n");
4384        resync = mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active);
4385        dt = (jiffies - mddev->resync_mark) / HZ;
4386        if (!dt) dt++;
4387        db = resync - mddev->resync_mark_cnt;
4388        return sprintf(page, "%lu\n", db/dt/2); /* K/sec */
4389}
4390
4391static struct md_sysfs_entry md_sync_speed = __ATTR_RO(sync_speed);
4392
4393static ssize_t
4394sync_completed_show(struct mddev *mddev, char *page)
4395{
4396        unsigned long long max_sectors, resync;
4397
4398        if (!test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
4399                return sprintf(page, "none\n");
4400
4401        if (mddev->curr_resync == 1 ||
4402            mddev->curr_resync == 2)
4403                return sprintf(page, "delayed\n");
4404
4405        if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ||
4406            test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
4407                max_sectors = mddev->resync_max_sectors;
4408        else
4409                max_sectors = mddev->dev_sectors;
4410
4411        resync = mddev->curr_resync_completed;
4412        return sprintf(page, "%llu / %llu\n", resync, max_sectors);
4413}
4414
4415static struct md_sysfs_entry md_sync_completed = __ATTR_RO(sync_completed);
4416
4417static ssize_t
4418min_sync_show(struct mddev *mddev, char *page)
4419{
4420        return sprintf(page, "%llu\n",
4421                       (unsigned long long)mddev->resync_min);
4422}
4423static ssize_t
4424min_sync_store(struct mddev *mddev, const char *buf, size_t len)
4425{
4426        unsigned long long min;
4427        if (strict_strtoull(buf, 10, &min))
4428                return -EINVAL;
4429        if (min > mddev->resync_max)
4430                return -EINVAL;
4431        if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
4432                return -EBUSY;
4433
4434        /* Must be a multiple of chunk_size */
4435        if (mddev->chunk_sectors) {
4436                sector_t temp = min;
4437                if (sector_div(temp, mddev->chunk_sectors))
4438                        return -EINVAL;
4439        }
4440        mddev->resync_min = min;
4441
4442        return len;
4443}
4444
4445static struct md_sysfs_entry md_min_sync =
4446__ATTR(sync_min, S_IRUGO|S_IWUSR, min_sync_show, min_sync_store);
4447
4448static ssize_t
4449max_sync_show(struct mddev *mddev, char *page)
4450{
4451        if (mddev->resync_max == MaxSector)
4452                return sprintf(page, "max\n");
4453        else
4454                return sprintf(page, "%llu\n",
4455                               (unsigned long long)mddev->resync_max);
4456}
4457static ssize_t
4458max_sync_store(struct mddev *mddev, const char *buf, size_t len)
4459{
4460        if (strncmp(buf, "max", 3) == 0)
4461                mddev->resync_max = MaxSector;
4462        else {
4463                unsigned long long max;
4464                if (strict_strtoull(buf, 10, &max))
4465                        return -EINVAL;
4466                if (max < mddev->resync_min)
4467                        return -EINVAL;
4468                if (max < mddev->resync_max &&
4469                    mddev->ro == 0 &&
4470                    test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
4471                        return -EBUSY;
4472
4473                /* Must be a multiple of chunk_size */
4474                if (mddev->chunk_sectors) {
4475                        sector_t temp = max;
4476                        if (sector_div(temp, mddev->chunk_sectors))
4477                                return -EINVAL;
4478                }
4479                mddev->resync_max = max;
4480        }
4481        wake_up(&mddev->recovery_wait);
4482        return len;
4483}
4484
4485static struct md_sysfs_entry md_max_sync =
4486__ATTR(sync_max, S_IRUGO|S_IWUSR, max_sync_show, max_sync_store);
4487
4488static ssize_t
4489suspend_lo_show(struct mddev *mddev, char *page)
4490{
4491        return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_lo);
4492}
4493
4494static ssize_t
4495suspend_lo_store(struct mddev *mddev, const char *buf, size_t len)
4496{
4497        char *e;
4498        unsigned long long new = simple_strtoull(buf, &e, 10);
4499        unsigned long long old = mddev->suspend_lo;
4500
4501        if (mddev->pers == NULL || 
4502            mddev->pers->quiesce == NULL)
4503                return -EINVAL;
4504        if (buf == e || (*e && *e != '\n'))
4505                return -EINVAL;
4506
4507        mddev->suspend_lo = new;
4508        if (new >= old)
4509                /* Shrinking suspended region */
4510                mddev->pers->quiesce(mddev, 2);
4511        else {
4512                /* Expanding suspended region - need to wait */
4513                mddev->pers->quiesce(mddev, 1);
4514                mddev->pers->quiesce(mddev, 0);
4515        }
4516        return len;
4517}
4518static struct md_sysfs_entry md_suspend_lo =
4519__ATTR(suspend_lo, S_IRUGO|S_IWUSR, suspend_lo_show, suspend_lo_store);
4520
4521
4522static ssize_t
4523suspend_hi_show(struct mddev *mddev, char *page)
4524{
4525        return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_hi);
4526}
4527
4528static ssize_t
4529suspend_hi_store(struct mddev *mddev, const char *buf, size_t len)
4530{
4531        char *e;
4532        unsigned long long new = simple_strtoull(buf, &e, 10);
4533        unsigned long long old = mddev->suspend_hi;
4534
4535        if (mddev->pers == NULL ||
4536            mddev->pers->quiesce == NULL)
4537                return -EINVAL;
4538        if (buf == e || (*e && *e != '\n'))
4539                return -EINVAL;
4540
4541        mddev->suspend_hi = new;
4542        if (new <= old)
4543                /* Shrinking suspended region */
4544                mddev->pers->quiesce(mddev, 2);
4545        else {
4546                /* Expanding suspended region - need to wait */
4547                mddev->pers->quiesce(mddev, 1);
4548                mddev->pers->quiesce(mddev, 0);
4549        }
4550        return len;
4551}
4552static struct md_sysfs_entry md_suspend_hi =
4553__ATTR(suspend_hi, S_IRUGO|S_IWUSR, suspend_hi_show, suspend_hi_store);
4554
4555static ssize_t
4556reshape_position_show(struct mddev *mddev, char *page)
4557{
4558        if (mddev->reshape_position != MaxSector)
4559                return sprintf(page, "%llu\n",
4560                               (unsigned long long)mddev->reshape_position);
4561        strcpy(page, "none\n");
4562        return 5;
4563}
4564
4565static ssize_t
4566reshape_position_store(struct mddev *mddev, const char *buf, size_t len)
4567{
4568        struct md_rdev *rdev;
4569        char *e;
4570        unsigned long long new = simple_strtoull(buf, &e, 10);
4571        if (mddev->pers)
4572                return -EBUSY;
4573        if (buf == e || (*e && *e != '\n'))
4574                return -EINVAL;
4575        mddev->reshape_position = new;
4576        mddev->delta_disks = 0;
4577        mddev->reshape_backwards = 0;
4578        mddev->new_level = mddev->level;
4579        mddev->new_layout = mddev->layout;
4580        mddev->new_chunk_sectors = mddev->chunk_sectors;
4581        rdev_for_each(rdev, mddev)
4582                rdev->new_data_offset = rdev->data_offset;
4583        return len;
4584}
4585
4586static struct md_sysfs_entry md_reshape_position =
4587__ATTR(reshape_position, S_IRUGO|S_IWUSR, reshape_position_show,
4588       reshape_position_store);
4589
4590static ssize_t
4591reshape_direction_show(struct mddev *mddev, char *page)
4592{
4593        return sprintf(page, "%s\n",
4594                       mddev->reshape_backwards ? "backwards" : "forwards");
4595}
4596
4597static ssize_t
4598reshape_direction_store(struct mddev *mddev, const char *buf, size_t len)
4599{
4600        int backwards = 0;
4601        if (cmd_match(buf, "forwards"))
4602                backwards = 0;
4603        else if (cmd_match(buf, "backwards"))
4604                backwards = 1;
4605        else
4606                return -EINVAL;
4607        if (mddev->reshape_backwards == backwards)
4608                return len;
4609
4610        /* check if we are allowed to change */
4611        if (mddev->delta_disks)
4612                return -EBUSY;
4613
4614        if (mddev->persistent &&
4615            mddev->major_version == 0)
4616                return -EINVAL;
4617
4618        mddev->reshape_backwards = backwards;
4619        return len;
4620}
4621
4622static struct md_sysfs_entry md_reshape_direction =
4623__ATTR(reshape_direction, S_IRUGO|S_IWUSR, reshape_direction_show,
4624       reshape_direction_store);
4625
4626static ssize_t
4627array_size_show(struct mddev *mddev, char *page)
4628{
4629        if (mddev->external_size)
4630                return sprintf(page, "%llu\n",
4631                               (unsigned long long)mddev->array_sectors/2);
4632        else
4633                return sprintf(page, "default\n");
4634}
4635
4636static ssize_t
4637array_size_store(struct mddev *mddev, const char *buf, size_t len)
4638{
4639        sector_t sectors;
4640
4641        if (strncmp(buf, "default", 7) == 0) {
4642                if (mddev->pers)
4643                        sectors = mddev->pers->size(mddev, 0, 0);
4644                else
4645                        sectors = mddev->array_sectors;
4646
4647                mddev->external_size = 0;
4648        } else {
4649                if (strict_blocks_to_sectors(buf, &sectors) < 0)
4650                        return -EINVAL;
4651                if (mddev->pers && mddev->pers->size(mddev, 0, 0) < sectors)
4652                        return -E2BIG;
4653
4654                mddev->external_size = 1;
4655        }
4656
4657        mddev->array_sectors = sectors;
4658        if (mddev->pers) {
4659                set_capacity(mddev->gendisk, mddev->array_sectors);
4660                revalidate_disk(mddev->gendisk);
4661        }
4662        return len;
4663}
4664
4665static struct md_sysfs_entry md_array_size =
4666__ATTR(array_size, S_IRUGO|S_IWUSR, array_size_show,
4667       array_size_store);
4668
4669static struct attribute *md_default_attrs[] = {
4670        &md_level.attr,
4671        &md_layout.attr,
4672        &md_raid_disks.attr,
4673        &md_chunk_size.attr,
4674        &md_size.attr,
4675        &md_resync_start.attr,
4676        &md_metadata.attr,
4677        &md_new_device.attr,
4678        &md_safe_delay.attr,
4679        &md_array_state.attr,
4680        &md_reshape_position.attr,
4681        &md_reshape_direction.attr,
4682        &md_array_size.attr,
4683        &max_corr_read_errors.attr,
4684        NULL,
4685};
4686
4687static struct attribute *md_redundancy_attrs[] = {
4688        &md_scan_mode.attr,
4689        &md_mismatches.attr,
4690        &md_sync_min.attr,
4691        &md_sync_max.attr,
4692        &md_sync_speed.attr,
4693        &md_sync_force_parallel.attr,
4694        &md_sync_completed.attr,
4695        &md_min_sync.attr,
4696        &md_max_sync.attr,
4697        &md_suspend_lo.attr,
4698        &md_suspend_hi.attr,
4699        &md_bitmap.attr,
4700        &md_degraded.attr,
4701        NULL,
4702};
4703static struct attribute_group md_redundancy_group = {
4704        .name = NULL,
4705        .attrs = md_redundancy_attrs,
4706};
4707
4708
4709static ssize_t
4710md_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
4711{
4712        struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
4713        struct mddev *mddev = container_of(kobj, struct mddev, kobj);
4714        ssize_t rv;
4715
4716        if (!entry->show)
4717                return -EIO;
4718        spin_lock(&all_mddevs_lock);
4719        if (list_empty(&mddev->all_mddevs)) {
4720                spin_unlock(&all_mddevs_lock);
4721                return -EBUSY;
4722        }
4723        mddev_get(mddev);
4724        spin_unlock(&all_mddevs_lock);
4725
4726        rv = mddev_lock(mddev);
4727        if (!rv) {
4728                rv = entry->show(mddev, page);
4729                mddev_unlock(mddev);
4730        }
4731        mddev_put(mddev);
4732        return rv;
4733}
4734
4735static ssize_t
4736md_attr_store(struct kobject *kobj, struct attribute *attr,
4737              const char *page, size_t length)
4738{
4739        struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
4740        struct mddev *mddev = container_of(kobj, struct mddev, kobj);
4741        ssize_t rv;
4742
4743        if (!entry->store)
4744                return -EIO;
4745        if (!capable(CAP_SYS_ADMIN))
4746                return -EACCES;
4747        spin_lock(&all_mddevs_lock);
4748        if (list_empty(&mddev->all_mddevs)) {
4749                spin_unlock(&all_mddevs_lock);
4750                return -EBUSY;
4751        }
4752        mddev_get(mddev);
4753        spin_unlock(&all_mddevs_lock);
4754        if (entry->store == new_dev_store)
4755                flush_workqueue(md_misc_wq);
4756        rv = mddev_lock(mddev);
4757        if (!rv) {
4758                rv = entry->store(mddev, page, length);
4759                mddev_unlock(mddev);
4760        }
4761        mddev_put(mddev);
4762        return rv;
4763}
4764
4765static void md_free(struct kobject *ko)
4766{
4767        struct mddev *mddev = container_of(ko, struct mddev, kobj);
4768
4769        if (mddev->sysfs_state)
4770                sysfs_put(mddev->sysfs_state);
4771
4772        if (mddev->gendisk) {
4773                del_gendisk(mddev->gendisk);
4774                put_disk(mddev->gendisk);
4775        }
4776        if (mddev->queue)
4777                blk_cleanup_queue(mddev->queue);
4778
4779        kfree(mddev);
4780}
4781
4782static const struct sysfs_ops md_sysfs_ops = {
4783        .show   = md_attr_show,
4784        .store  = md_attr_store,
4785};
4786static struct kobj_type md_ktype = {
4787        .release        = md_free,
4788        .sysfs_ops      = &md_sysfs_ops,
4789        .default_attrs  = md_default_attrs,
4790};
4791
4792int mdp_major = 0;
4793
4794static void mddev_delayed_delete(struct work_struct *ws)
4795{
4796        struct mddev *mddev = container_of(ws, struct mddev, del_work);
4797
4798        sysfs_remove_group(&mddev->kobj, &md_bitmap_group);
4799        kobject_del(&mddev->kobj);
4800        kobject_put(&mddev->kobj);
4801}
4802
4803static int md_alloc(dev_t dev, char *name)
4804{
4805        static DEFINE_MUTEX(disks_mutex);
4806        struct mddev *mddev = mddev_find(dev);
4807        struct gendisk *disk;
4808        int partitioned;
4809        int shift;
4810        int unit;
4811        int error;
4812
4813        if (!mddev)
4814                return -ENODEV;
4815
4816        partitioned = (MAJOR(mddev->unit) != MD_MAJOR);
4817        shift = partitioned ? MdpMinorShift : 0;
4818        unit = MINOR(mddev->unit) >> shift;
4819
4820        /* wait for any previous instance of this device to be
4821         * completely removed (mddev_delayed_delete).
4822         */
4823        flush_workqueue(md_misc_wq);
4824
4825        mutex_lock(&disks_mutex);
4826        error = -EEXIST;
4827        if (mddev->gendisk)
4828                goto abort;
4829
4830        if (name) {
4831                /* Need to ensure that 'name' is not a duplicate.
4832                 */
4833                struct mddev *mddev2;
4834                spin_lock(&all_mddevs_lock);
4835
4836                list_for_each_entry(mddev2, &all_mddevs, all_mddevs)
4837                        if (mddev2->gendisk &&
4838                            strcmp(mddev2->gendisk->disk_name, name) == 0) {
4839                                spin_unlock(&all_mddevs_lock);
4840                                goto abort;
4841                        }
4842                spin_unlock(&all_mddevs_lock);
4843        }
4844
4845        error = -ENOMEM;
4846        mddev->queue = blk_alloc_queue(GFP_KERNEL);
4847        if (!mddev->queue)
4848                goto abort;
4849        mddev->queue->queuedata = mddev;
4850
4851        blk_queue_make_request(mddev->queue, md_make_request);
4852        blk_set_stacking_limits(&mddev->queue->limits);
4853
4854        disk = alloc_disk(1 << shift);
4855        if (!disk) {
4856                blk_cleanup_queue(mddev->queue);
4857                mddev->queue = NULL;
4858                goto abort;
4859        }
4860        disk->major = MAJOR(mddev->unit);
4861        disk->first_minor = unit << shift;
4862        if (name)
4863                strcpy(disk->disk_name, name);
4864        else if (partitioned)
4865                sprintf(disk->disk_name, "md_d%d", unit);
4866        else
4867                sprintf(disk->disk_name, "md%d", unit);
4868        disk->fops = &md_fops;
4869        disk->private_data = mddev;
4870        disk->queue = mddev->queue;
4871        blk_queue_flush(mddev->queue, REQ_FLUSH | REQ_FUA);
4872        /* Allow extended partitions.  This makes the
4873         * 'mdp' device redundant, but we can't really
4874         * remove it now.
4875         */
4876        disk->flags |= GENHD_FL_EXT_DEVT;
4877        mddev->gendisk = disk;
4878        /* As soon as we call add_disk(), another thread could get
4879         * through to md_open, so make sure it doesn't get too far
4880         */
4881        mutex_lock(&mddev->open_mutex);
4882        add_disk(disk);
4883
4884        error = kobject_init_and_add(&mddev->kobj, &md_ktype,
4885                                     &disk_to_dev(disk)->kobj, "%s", "md");
4886        if (error) {
4887                /* This isn't possible, but as kobject_init_and_add is marked
4888                 * __must_check, we must do something with the result
4889                 */
4890                printk(KERN_WARNING "md: cannot register %s/md - name in use\n",
4891                       disk->disk_name);
4892                error = 0;
4893        }
4894        if (mddev->kobj.sd &&
4895            sysfs_create_group(&mddev->kobj, &md_bitmap_group))
4896                printk(KERN_DEBUG "pointless warning\n");
4897        mutex_unlock(&mddev->open_mutex);
4898 abort:
4899        mutex_unlock(&disks_mutex);
4900        if (!error && mddev->kobj.sd) {
4901                kobject_uevent(&mddev->kobj, KOBJ_ADD);
4902                mddev->sysfs_state = sysfs_get_dirent_safe(mddev->kobj.sd, "array_state");
4903        }
4904        mddev_put(mddev);
4905        return error;
4906}
4907
4908static struct kobject *md_probe(dev_t dev, int *part, void *data)
4909{
4910        md_alloc(dev, NULL);
4911        return NULL;
4912}
4913
4914static int add_named_array(const char *val, struct kernel_param *kp)
4915{
4916        /* val must be "md_*" where * is not all digits.
4917         * We allocate an array with a large free minor number, and
4918         * set the name to val.  val must not already be an active name.
4919         */
4920        int len = strlen(val);
4921        char buf[DISK_NAME_LEN];
4922
4923        while (len && val[len-1] == '\n')
4924                len--;
4925        if (len >= DISK_NAME_LEN)
4926                return -E2BIG;
4927        strlcpy(buf, val, len+1);
4928        if (strncmp(buf, "md_", 3) != 0)
4929                return -EINVAL;
4930        return md_alloc(0, buf);
4931}
4932
4933static void md_safemode_timeout(unsigned long data)
4934{
4935        struct mddev *mddev = (struct mddev *) data;
4936
4937        if (!atomic_read(&mddev->writes_pending)) {
4938                mddev->safemode = 1;
4939                if (mddev->external)
4940                        sysfs_notify_dirent_safe(mddev->sysfs_state);
4941        }
4942        md_wakeup_thread(mddev->thread);
4943}
4944
4945static int start_dirty_degraded;
4946
4947int md_run(struct mddev *mddev)
4948{
4949        int err;
4950        struct md_rdev *rdev;
4951        struct md_personality *pers;
4952
4953        if (list_empty(&mddev->disks))
4954                /* cannot run an array with no devices.. */
4955                return -EINVAL;
4956
4957        if (mddev->pers)
4958                return -EBUSY;
4959        /* Cannot run until previous stop completes properly */
4960        if (mddev->sysfs_active)
4961                return -EBUSY;
4962
4963        /*
4964         * Analyze all RAID superblock(s)
4965         */
4966        if (!mddev->raid_disks) {
4967                if (!mddev->persistent)
4968                        return -EINVAL;
4969                analyze_sbs(mddev);
4970        }
4971
4972        if (mddev->level != LEVEL_NONE)
4973                request_module("md-level-%d", mddev->level);
4974        else if (mddev->clevel[0])
4975                request_module("md-%s", mddev->clevel);
4976
4977        /*
4978         * Drop all container device buffers, from now on
4979         * the only valid external interface is through the md
4980         * device.
4981         */
4982        rdev_for_each(rdev, mddev) {
4983                if (test_bit(Faulty, &rdev->flags))
4984                        continue;
4985                sync_blockdev(rdev->bdev);
4986                invalidate_bdev(rdev->bdev);
4987
4988                /* perform some consistency tests on the device.
4989                 * We don't want the data to overlap the metadata,
4990                 * Internal Bitmap issues have been handled elsewhere.
4991                 */
4992                if (rdev->meta_bdev) {
4993                        /* Nothing to check */;
4994                } else if (rdev->data_offset < rdev->sb_start) {
4995                        if (mddev->dev_sectors &&
4996                            rdev->data_offset + mddev->dev_sectors
4997                            > rdev->sb_start) {
4998                                printk("md: %s: data overlaps metadata\n",
4999                                       mdname(mddev));
5000                                return -EINVAL;
5001                        }
5002                } else {
5003                        if (rdev->sb_start + rdev->sb_size/512
5004                            > rdev->data_offset) {
5005                                printk("md: %s: metadata overlaps data\n",
5006                                       mdname(mddev));
5007                                return -EINVAL;
5008                        }
5009                }
5010                sysfs_notify_dirent_safe(rdev->sysfs_state);
5011        }
5012
5013        if (mddev->bio_set == NULL)
5014                mddev->bio_set = bioset_create(BIO_POOL_SIZE, 0);
5015
5016        spin_lock(&pers_lock);
5017        pers = find_pers(mddev->level, mddev->clevel);
5018        if (!pers || !try_module_get(pers->owner)) {
5019                spin_unlock(&pers_lock);
5020                if (mddev->level != LEVEL_NONE)
5021                        printk(KERN_WARNING "md: personality for level %d is not loaded!\n",
5022                               mddev->level);
5023                else
5024                        printk(KERN_WARNING "md: personality for level %s is not loaded!\n",
5025                               mddev->clevel);
5026                return -EINVAL;
5027        }
5028        mddev->pers = pers;
5029        spin_unlock(&pers_lock);
5030        if (mddev->level != pers->level) {
5031                mddev->level = pers->level;
5032                mddev->new_level = pers->level;
5033        }
5034        strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
5035
5036        if (mddev->reshape_position != MaxSector &&
5037            pers->start_reshape == NULL) {
5038                /* This personality cannot handle reshaping... */
5039                mddev->pers = NULL;
5040                module_put(pers->owner);
5041                return -EINVAL;
5042        }
5043
5044        if (pers->sync_request) {
5045                /* Warn if this is a potentially silly
5046                 * configuration.
5047                 */
5048                char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
5049                struct md_rdev *rdev2;
5050                int warned = 0;
5051
5052                rdev_for_each(rdev, mddev)
5053                        rdev_for_each(rdev2, mddev) {
5054                                if (rdev < rdev2 &&
5055                                    rdev->bdev->bd_contains ==
5056                                    rdev2->bdev->bd_contains) {
5057                                        printk(KERN_WARNING
5058                                               "%s: WARNING: %s appears to be"
5059                                               " on the same physical disk as"
5060                                               " %s.\n",
5061                                               mdname(mddev),
5062                                               bdevname(rdev->bdev,b),
5063                                               bdevname(rdev2->bdev,b2));
5064                                        warned = 1;
5065                                }
5066                        }
5067
5068                if (warned)
5069                        printk(KERN_WARNING
5070                               "True protection against single-disk"
5071                               " failure might be compromised.\n");
5072        }
5073
5074        mddev->recovery = 0;
5075        /* may be over-ridden by personality */
5076        mddev->resync_max_sectors = mddev->dev_sectors;
5077
5078        mddev->ok_start_degraded = start_dirty_degraded;
5079
5080        if (start_readonly && mddev->ro == 0)
5081                mddev->ro = 2; /* read-only, but switch on first write */
5082
5083        err = mddev->pers->run(mddev);
5084        if (err)
5085                printk(KERN_ERR "md: pers->run() failed ...\n");
5086        else if (mddev->pers->size(mddev, 0, 0) < mddev->array_sectors) {
5087                WARN_ONCE(!mddev->external_size, "%s: default size too small,"
5088                          " but 'external_size' not in effect?\n", __func__);
5089                printk(KERN_ERR
5090                       "md: invalid array_size %llu > default size %llu\n",
5091                       (unsigned long long)mddev->array_sectors / 2,
5092                       (unsigned long long)mddev->pers->size(mddev, 0, 0) / 2);
5093                err = -EINVAL;
5094                mddev->pers->stop(mddev);
5095        }
5096        if (err == 0 && mddev->pers->sync_request &&
5097            (mddev->bitmap_info.file || mddev->bitmap_info.offset)) {
5098                err = bitmap_create(mddev);
5099                if (err) {
5100                        printk(KERN_ERR "%s: failed to create bitmap (%d)\n",
5101                               mdname(mddev), err);
5102                        mddev->pers->stop(mddev);
5103                }
5104        }
5105        if (err) {
5106                module_put(mddev->pers->owner);
5107                mddev->pers = NULL;
5108                bitmap_destroy(mddev);
5109                return err;
5110        }
5111        if (mddev->pers->sync_request) {
5112                if (mddev->kobj.sd &&
5113                    sysfs_create_group(&mddev->kobj, &md_redundancy_group))
5114                        printk(KERN_WARNING
5115                               "md: cannot register extra attributes for %s\n",
5116                               mdname(mddev));
5117                mddev->sysfs_action = sysfs_get_dirent_safe(mddev->kobj.sd, "sync_action");
5118        } else if (mddev->ro == 2) /* auto-readonly not meaningful */
5119                mddev->ro = 0;
5120
5121        atomic_set(&mddev->writes_pending,0);
5122        atomic_set(&mddev->max_corr_read_errors,
5123                   MD_DEFAULT_MAX_CORRECTED_READ_ERRORS);
5124        mddev->safemode = 0;
5125        mddev->safemode_timer.function = md_safemode_timeout;
5126        mddev->safemode_timer.data = (unsigned long) mddev;
5127        mddev->safemode_delay = (200 * HZ)/1000 +1; /* 200 msec delay */
5128        mddev->in_sync = 1;
5129        smp_wmb();
5130        mddev->ready = 1;
5131        rdev_for_each(rdev, mddev)
5132                if (rdev->raid_disk >= 0)
5133                        if (sysfs_link_rdev(mddev, rdev))
5134                                /* failure here is OK */;
5135        
5136        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5137        
5138        if (mddev->flags)
5139                md_update_sb(mddev, 0);
5140
5141        md_new_event(mddev);
5142        sysfs_notify_dirent_safe(mddev->sysfs_state);
5143        sysfs_notify_dirent_safe(mddev->sysfs_action);
5144        sysfs_notify(&mddev->kobj, NULL, "degraded");
5145        return 0;
5146}
5147EXPORT_SYMBOL_GPL(md_run);
5148
5149static int do_md_run(struct mddev *mddev)
5150{
5151        int err;
5152
5153        err = md_run(mddev);
5154        if (err)
5155                goto out;
5156        err = bitmap_load(mddev);
5157        if (err) {
5158                bitmap_destroy(mddev);
5159                goto out;
5160        }
5161
5162        md_wakeup_thread(mddev->thread);
5163        md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
5164
5165        set_capacity(mddev->gendisk, mddev->array_sectors);
5166        revalidate_disk(mddev->gendisk);
5167        mddev->changed = 1;
5168        kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
5169out:
5170        return err;
5171}
5172
5173static int restart_array(struct mddev *mddev)
5174{
5175        struct gendisk *disk = mddev->gendisk;