err.no Git - linux-2.6/blob - drivers/md/md.c

   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/module.h>
  36 #include <linux/kernel.h>
  37 #include <linux/kthread.h>
  38 #include <linux/linkage.h>
  39 #include <linux/raid/md.h>
  40 #include <linux/raid/bitmap.h>
  41 #include <linux/sysctl.h>
  42 #include <linux/buffer_head.h> /* for invalidate_bdev */
  43 #include <linux/poll.h>
  44 #include <linux/mutex.h>
  45 #include <linux/ctype.h>
  46 #include <linux/freezer.h>
  47
  48 #include <linux/init.h>
  49
  50 #include <linux/file.h>
  51
  52 #ifdef CONFIG_KMOD
  53 #include <linux/kmod.h>
  54 #endif
  55
  56 #include <asm/unaligned.h>
  57
  58 #define MAJOR_NR MD_MAJOR
  59 #define MD_DRIVER
  60
  61 /* 63 partitions with the alternate major number (mdp) */
  62 #define MdpMinorShift 6
  63
  64 #define DEBUG 0
  65 #define dprintk(x...) ((void)(DEBUG && printk(x)))
  66
  67
  68 #ifndef MODULE
  69 static void autostart_arrays (int part);
  70 #endif
  71
  72 static LIST_HEAD(pers_list);
  73 static DEFINE_SPINLOCK(pers_lock);
  74
  75 static void md_print_devices(void);
  76
  77 static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
  78
  79 #define MD_BUG(x...) { printk("md: bug in file %s, line %d\n", __FILE__, __LINE__); md_print_devices(); }
  80
  81 /*
  82  * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
  83  * is 1000 KB/sec, so the extra system load does not show up that much.
  84  * Increase it if you want to have more _guaranteed_ speed. Note that
  85  * the RAID driver will use the maximum available bandwidth if the IO
  86  * subsystem is idle. There is also an 'absolute maximum' reconstruction
  87  * speed limit - in case reconstruction slows down your system despite
  88  * idle IO detection.
  89  *
  90  * you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
  91  * or /sys/block/mdX/md/sync_speed_{min,max}
  92  */
  93
  94 static int sysctl_speed_limit_min = 1000;
  95 static int sysctl_speed_limit_max = 200000;
  96 static inline int speed_min(mddev_t *mddev)
  97 {
  98         return mddev->sync_speed_min ?
  99                 mddev->sync_speed_min : sysctl_speed_limit_min;
 100 }
 101
 102 static inline int speed_max(mddev_t *mddev)
 103 {
 104         return mddev->sync_speed_max ?
 105                 mddev->sync_speed_max : sysctl_speed_limit_max;
 106 }
 107
 108 static struct ctl_table_header *raid_table_header;
 109
 110 static ctl_table raid_table[] = {
 111         {
 112                 .ctl_name       = DEV_RAID_SPEED_LIMIT_MIN,
 113                 .procname       = "speed_limit_min",
 114                 .data           = &sysctl_speed_limit_min,
 115                 .maxlen         = sizeof(int),
 116                 .mode           = S_IRUGO|S_IWUSR,
 117                 .proc_handler   = &proc_dointvec,
 118         },
 119         {
 120                 .ctl_name       = DEV_RAID_SPEED_LIMIT_MAX,
 121                 .procname       = "speed_limit_max",
 122                 .data           = &sysctl_speed_limit_max,
 123                 .maxlen         = sizeof(int),
 124                 .mode           = S_IRUGO|S_IWUSR,
 125                 .proc_handler   = &proc_dointvec,
 126         },
 127         { .ctl_name = 0 }
 128 };
 129
 130 static ctl_table raid_dir_table[] = {
 131         {
 132                 .ctl_name       = DEV_RAID,
 133                 .procname       = "raid",
 134                 .maxlen         = 0,
 135                 .mode           = S_IRUGO|S_IXUGO,
 136                 .child          = raid_table,
 137         },
 138         { .ctl_name = 0 }
 139 };
 140
 141 static ctl_table raid_root_table[] = {
 142         {
 143                 .ctl_name       = CTL_DEV,
 144                 .procname       = "dev",
 145                 .maxlen         = 0,
 146                 .mode           = 0555,
 147                 .child          = raid_dir_table,
 148         },
 149         { .ctl_name = 0 }
 150 };
 151
 152 static struct block_device_operations md_fops;
 153
 154 static int start_readonly;
 155
 156 /*
 157  * We have a system wide 'event count' that is incremented
 158  * on any 'interesting' event, and readers of /proc/mdstat
 159  * can use 'poll' or 'select' to find out when the event
 160  * count increases.
 161  *
 162  * Events are:
 163  *  start array, stop array, error, add device, remove device,
 164  *  start build, activate spare
 165  */
 166 static DECLARE_WAIT_QUEUE_HEAD(md_event_waiters);
 167 static atomic_t md_event_count;
 168 void md_new_event(mddev_t *mddev)
 169 {
 170         atomic_inc(&md_event_count);
 171         wake_up(&md_event_waiters);
 172 }
 173 EXPORT_SYMBOL_GPL(md_new_event);
 174
 175 /* Alternate version that can be called from interrupts
 176  * when calling sysfs_notify isn't needed.
 177  */
 178 static void md_new_event_inintr(mddev_t *mddev)
 179 {
 180         atomic_inc(&md_event_count);
 181         wake_up(&md_event_waiters);
 182 }
 183
 184 /*
 185  * Enables to iterate over all existing md arrays
 186  * all_mddevs_lock protects this list.
 187  */
 188 static LIST_HEAD(all_mddevs);
 189 static DEFINE_SPINLOCK(all_mddevs_lock);
 190
 191
 192 /*
 193  * iterates through all used mddevs in the system.
 194  * We take care to grab the all_mddevs_lock whenever navigating
 195  * the list, and to always hold a refcount when unlocked.
 196  * Any code which breaks out of this loop while own
 197  * a reference to the current mddev and must mddev_put it.
 198  */
 199 #define for_each_mddev(mddev,tmp)                                       \
 200                                                                         \
 201         for (({ spin_lock(&all_mddevs_lock);                            \
 202                 tmp = all_mddevs.next;                                  \
 203                 mddev = NULL;});                                        \
 204              ({ if (tmp != &all_mddevs)                                 \
 205                         mddev_get(list_entry(tmp, mddev_t, all_mddevs));\
 206                 spin_unlock(&all_mddevs_lock);                          \
 207                 if (mddev) mddev_put(mddev);                            \
 208                 mddev = list_entry(tmp, mddev_t, all_mddevs);           \
 209                 tmp != &all_mddevs;});                                  \
 210              ({ spin_lock(&all_mddevs_lock);                            \
 211                 tmp = tmp->next;})                                      \
 212                 )
 213
 214
 215 static int md_fail_request (struct request_queue *q, struct bio *bio)
 216 {
 217         bio_io_error(bio);
 218         return 0;
 219 }
 220
 221 static inline mddev_t *mddev_get(mddev_t *mddev)
 222 {
 223         atomic_inc(&mddev->active);
 224         return mddev;
 225 }
 226
 227 static void mddev_put(mddev_t *mddev)
 228 {
 229         if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
 230                 return;
 231         if (!mddev->raid_disks && list_empty(&mddev->disks)) {
 232                 list_del(&mddev->all_mddevs);
 233                 spin_unlock(&all_mddevs_lock);
 234                 blk_cleanup_queue(mddev->queue);
 235                 kobject_put(&mddev->kobj);
 236         } else
 237                 spin_unlock(&all_mddevs_lock);
 238 }
 239
 240 static mddev_t * mddev_find(dev_t unit)
 241 {
 242         mddev_t *mddev, *new = NULL;
 243
 244  retry:
 245         spin_lock(&all_mddevs_lock);
 246         list_for_each_entry(mddev, &all_mddevs, all_mddevs)
 247                 if (mddev->unit == unit) {
 248                         mddev_get(mddev);
 249                         spin_unlock(&all_mddevs_lock);
 250                         kfree(new);
 251                         return mddev;
 252                 }
 253
 254         if (new) {
 255                 list_add(&new->all_mddevs, &all_mddevs);
 256                 spin_unlock(&all_mddevs_lock);
 257                 return new;
 258         }
 259         spin_unlock(&all_mddevs_lock);
 260
 261         new = kzalloc(sizeof(*new), GFP_KERNEL);
 262         if (!new)
 263                 return NULL;
 264
 265         new->unit = unit;
 266         if (MAJOR(unit) == MD_MAJOR)
 267                 new->md_minor = MINOR(unit);
 268         else
 269                 new->md_minor = MINOR(unit) >> MdpMinorShift;
 270
 271         mutex_init(&new->reconfig_mutex);
 272         INIT_LIST_HEAD(&new->disks);
 273         INIT_LIST_HEAD(&new->all_mddevs);
 274         init_timer(&new->safemode_timer);
 275         atomic_set(&new->active, 1);
 276         spin_lock_init(&new->write_lock);
 277         init_waitqueue_head(&new->sb_wait);
 278         init_waitqueue_head(&new->recovery_wait);
 279         new->reshape_position = MaxSector;
 280         new->resync_min = 0;
 281         new->resync_max = MaxSector;
 282         new->level = LEVEL_NONE;
 283
 284         new->queue = blk_alloc_queue(GFP_KERNEL);
 285         if (!new->queue) {
 286                 kfree(new);
 287                 return NULL;
 288         }
 289         /* Can be unlocked because the queue is new: no concurrency */
 290         queue_flag_set_unlocked(QUEUE_FLAG_CLUSTER, new->queue);
 291
 292         blk_queue_make_request(new->queue, md_fail_request);
 293
 294         goto retry;
 295 }
 296
 297 static inline int mddev_lock(mddev_t * mddev)
 298 {
 299         return mutex_lock_interruptible(&mddev->reconfig_mutex);
 300 }
 301
 302 static inline int mddev_trylock(mddev_t * mddev)
 303 {
 304         return mutex_trylock(&mddev->reconfig_mutex);
 305 }
 306
 307 static inline void mddev_unlock(mddev_t * mddev)
 308 {
 309         mutex_unlock(&mddev->reconfig_mutex);
 310
 311         md_wakeup_thread(mddev->thread);
 312 }
 313
 314 static mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr)
 315 {
 316         mdk_rdev_t * rdev;
 317         struct list_head *tmp;
 318
 319         rdev_for_each(rdev, tmp, mddev) {
 320                 if (rdev->desc_nr == nr)
 321                         return rdev;
 322         }
 323         return NULL;
 324 }
 325
 326 static mdk_rdev_t * find_rdev(mddev_t * mddev, dev_t dev)
 327 {
 328         struct list_head *tmp;
 329         mdk_rdev_t *rdev;
 330
 331         rdev_for_each(rdev, tmp, mddev) {
 332                 if (rdev->bdev->bd_dev == dev)
 333                         return rdev;
 334         }
 335         return NULL;
 336 }
 337
 338 static struct mdk_personality *find_pers(int level, char *clevel)
 339 {
 340         struct mdk_personality *pers;
 341         list_for_each_entry(pers, &pers_list, list) {
 342                 if (level != LEVEL_NONE && pers->level == level)
 343                         return pers;
 344                 if (strcmp(pers->name, clevel)==0)
 345                         return pers;
 346         }
 347         return NULL;
 348 }
 349
 350 /* return the offset of the super block in 512byte sectors */
 351 static inline sector_t calc_dev_sboffset(struct block_device *bdev)
 352 {
 353         sector_t num_sectors = bdev->bd_inode->i_size / 512;
 354         return MD_NEW_SIZE_SECTORS(num_sectors);
 355 }
 356
 357 static sector_t calc_num_sectors(mdk_rdev_t *rdev, unsigned chunk_size)
 358 {
 359         sector_t num_sectors = rdev->sb_start;
 360
 361         if (chunk_size)
 362                 num_sectors &= ~((sector_t)chunk_size/512 - 1);
 363         return num_sectors;
 364 }
 365
 366 static int alloc_disk_sb(mdk_rdev_t * rdev)
 367 {
 368         if (rdev->sb_page)
 369                 MD_BUG();
 370
 371         rdev->sb_page = alloc_page(GFP_KERNEL);
 372         if (!rdev->sb_page) {
 373                 printk(KERN_ALERT "md: out of memory.\n");
 374                 return -ENOMEM;
 375         }
 376
 377         return 0;
 378 }
 379
 380 static void free_disk_sb(mdk_rdev_t * rdev)
 381 {
 382         if (rdev->sb_page) {
 383                 put_page(rdev->sb_page);
 384                 rdev->sb_loaded = 0;
 385                 rdev->sb_page = NULL;
 386                 rdev->sb_start = 0;
 387                 rdev->size = 0;
 388         }
 389 }
 390
 391
 392 static void super_written(struct bio *bio, int error)
 393 {
 394         mdk_rdev_t *rdev = bio->bi_private;
 395         mddev_t *mddev = rdev->mddev;
 396
 397         if (error || !test_bit(BIO_UPTODATE, &bio->bi_flags)) {
 398                 printk("md: super_written gets error=%d, uptodate=%d\n",
 399                        error, test_bit(BIO_UPTODATE, &bio->bi_flags));
 400                 WARN_ON(test_bit(BIO_UPTODATE, &bio->bi_flags));
 401                 md_error(mddev, rdev);
 402         }
 403
 404         if (atomic_dec_and_test(&mddev->pending_writes))
 405                 wake_up(&mddev->sb_wait);
 406         bio_put(bio);
 407 }
 408
 409 static void super_written_barrier(struct bio *bio, int error)
 410 {
 411         struct bio *bio2 = bio->bi_private;
 412         mdk_rdev_t *rdev = bio2->bi_private;
 413         mddev_t *mddev = rdev->mddev;
 414
 415         if (!test_bit(BIO_UPTODATE, &bio->bi_flags) &&
 416             error == -EOPNOTSUPP) {
 417                 unsigned long flags;
 418                 /* barriers don't appear to be supported :-( */
 419                 set_bit(BarriersNotsupp, &rdev->flags);
 420                 mddev->barriers_work = 0;
 421                 spin_lock_irqsave(&mddev->write_lock, flags);
 422                 bio2->bi_next = mddev->biolist;
 423                 mddev->biolist = bio2;
 424                 spin_unlock_irqrestore(&mddev->write_lock, flags);
 425                 wake_up(&mddev->sb_wait);
 426                 bio_put(bio);
 427         } else {
 428                 bio_put(bio2);
 429                 bio->bi_private = rdev;
 430                 super_written(bio, error);
 431         }
 432 }
 433
 434 void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev,
 435                    sector_t sector, int size, struct page *page)
 436 {
 437         /* write first size bytes of page to sector of rdev
 438          * Increment mddev->pending_writes before returning
 439          * and decrement it on completion, waking up sb_wait
 440          * if zero is reached.
 441          * If an error occurred, call md_error
 442          *
 443          * As we might need to resubmit the request if BIO_RW_BARRIER
 444          * causes ENOTSUPP, we allocate a spare bio...
 445          */
 446         struct bio *bio = bio_alloc(GFP_NOIO, 1);
 447         int rw = (1<<BIO_RW) | (1<<BIO_RW_SYNC);
 448
 449         bio->bi_bdev = rdev->bdev;
 450         bio->bi_sector = sector;
 451         bio_add_page(bio, page, size, 0);
 452         bio->bi_private = rdev;
 453         bio->bi_end_io = super_written;
 454         bio->bi_rw = rw;
 455
 456         atomic_inc(&mddev->pending_writes);
 457         if (!test_bit(BarriersNotsupp, &rdev->flags)) {
 458                 struct bio *rbio;
 459                 rw |= (1<<BIO_RW_BARRIER);
 460                 rbio = bio_clone(bio, GFP_NOIO);
 461                 rbio->bi_private = bio;
 462                 rbio->bi_end_io = super_written_barrier;
 463                 submit_bio(rw, rbio);
 464         } else
 465                 submit_bio(rw, bio);
 466 }
 467
 468 void md_super_wait(mddev_t *mddev)
 469 {
 470         /* wait for all superblock writes that were scheduled to complete.
 471          * if any had to be retried (due to BARRIER problems), retry them
 472          */
 473         DEFINE_WAIT(wq);
 474         for(;;) {
 475                 prepare_to_wait(&mddev->sb_wait, &wq, TASK_UNINTERRUPTIBLE);
 476                 if (atomic_read(&mddev->pending_writes)==0)
 477                         break;
 478                 while (mddev->biolist) {
 479                         struct bio *bio;
 480                         spin_lock_irq(&mddev->write_lock);
 481                         bio = mddev->biolist;
 482                         mddev->biolist = bio->bi_next ;
 483                         bio->bi_next = NULL;
 484                         spin_unlock_irq(&mddev->write_lock);
 485                         submit_bio(bio->bi_rw, bio);
 486                 }
 487                 schedule();
 488         }
 489         finish_wait(&mddev->sb_wait, &wq);
 490 }
 491
 492 static void bi_complete(struct bio *bio, int error)
 493 {
 494         complete((struct completion*)bio->bi_private);
 495 }
 496
 497 int sync_page_io(struct block_device *bdev, sector_t sector, int size,
 498                    struct page *page, int rw)
 499 {
 500         struct bio *bio = bio_alloc(GFP_NOIO, 1);
 501         struct completion event;
 502         int ret;
 503
 504         rw |= (1 << BIO_RW_SYNC);
 505
 506         bio->bi_bdev = bdev;
 507         bio->bi_sector = sector;
 508         bio_add_page(bio, page, size, 0);
 509         init_completion(&event);
 510         bio->bi_private = &event;
 511         bio->bi_end_io = bi_complete;
 512         submit_bio(rw, bio);
 513         wait_for_completion(&event);
 514
 515         ret = test_bit(BIO_UPTODATE, &bio->bi_flags);
 516         bio_put(bio);
 517         return ret;
 518 }
 519 EXPORT_SYMBOL_GPL(sync_page_io);
 520
 521 static int read_disk_sb(mdk_rdev_t * rdev, int size)
 522 {
 523         char b[BDEVNAME_SIZE];
 524         if (!rdev->sb_page) {
 525                 MD_BUG();
 526                 return -EINVAL;
 527         }
 528         if (rdev->sb_loaded)
 529                 return 0;
 530
 531
 532         if (!sync_page_io(rdev->bdev, rdev->sb_start, size, rdev->sb_page, READ))
 533                 goto fail;
 534         rdev->sb_loaded = 1;
 535         return 0;
 536
 537 fail:
 538         printk(KERN_WARNING "md: disabled device %s, could not read superblock.\n",
 539                 bdevname(rdev->bdev,b));
 540         return -EINVAL;
 541 }
 542
 543 static int uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 544 {
 545         return  sb1->set_uuid0 == sb2->set_uuid0 &&
 546                 sb1->set_uuid1 == sb2->set_uuid1 &&
 547                 sb1->set_uuid2 == sb2->set_uuid2 &&
 548                 sb1->set_uuid3 == sb2->set_uuid3;
 549 }
 550
 551 static int sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 552 {
 553         int ret;
 554         mdp_super_t *tmp1, *tmp2;
 555
 556         tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
 557         tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
 558
 559         if (!tmp1 || !tmp2) {
 560                 ret = 0;
 561                 printk(KERN_INFO "md.c sb_equal(): failed to allocate memory!\n");
 562                 goto abort;
 563         }
 564
 565         *tmp1 = *sb1;
 566         *tmp2 = *sb2;
 567
 568         /*
 569          * nr_disks is not constant
 570          */
 571         tmp1->nr_disks = 0;
 572         tmp2->nr_disks = 0;
 573
 574         ret = (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4) == 0);
 575 abort:
 576         kfree(tmp1);
 577         kfree(tmp2);
 578         return ret;
 579 }
 580
 581
 582 static u32 md_csum_fold(u32 csum)
 583 {
 584         csum = (csum & 0xffff) + (csum >> 16);
 585         return (csum & 0xffff) + (csum >> 16);
 586 }
 587
 588 static unsigned int calc_sb_csum(mdp_super_t * sb)
 589 {
 590         u64 newcsum = 0;
 591         u32 *sb32 = (u32*)sb;
 592         int i;
 593         unsigned int disk_csum, csum;
 594
 595         disk_csum = sb->sb_csum;
 596         sb->sb_csum = 0;
 597
 598         for (i = 0; i < MD_SB_BYTES/4 ; i++)
 599                 newcsum += sb32[i];
 600         csum = (newcsum & 0xffffffff) + (newcsum>>32);
 601
 602
 603 #ifdef CONFIG_ALPHA
 604         /* This used to use csum_partial, which was wrong for several
 605          * reasons including that different results are returned on
 606          * different architectures.  It isn't critical that we get exactly
 607          * the same return value as before (we always csum_fold before
 608          * testing, and that removes any differences).  However as we
 609          * know that csum_partial always returned a 16bit value on
 610          * alphas, do a fold to maximise conformity to previous behaviour.
 611          */
 612         sb->sb_csum = md_csum_fold(disk_csum);
 613 #else
 614         sb->sb_csum = disk_csum;
 615 #endif
 616         return csum;
 617 }
 618
 619
 620 /*
 621  * Handle superblock details.
 622  * We want to be able to handle multiple superblock formats
 623  * so we have a common interface to them all, and an array of
 624  * different handlers.
 625  * We rely on user-space to write the initial superblock, and support
 626  * reading and updating of superblocks.
 627  * Interface methods are:
 628  *   int load_super(mdk_rdev_t *dev, mdk_rdev_t *refdev, int minor_version)
 629  *      loads and validates a superblock on dev.
 630  *      if refdev != NULL, compare superblocks on both devices
 631  *    Return:
 632  *      0 - dev has a superblock that is compatible with refdev
 633  *      1 - dev has a superblock that is compatible and newer than refdev
 634  *          so dev should be used as the refdev in future
 635  *     -EINVAL superblock incompatible or invalid
 636  *     -othererror e.g. -EIO
 637  *
 638  *   int validate_super(mddev_t *mddev, mdk_rdev_t *dev)
 639  *      Verify that dev is acceptable into mddev.
 640  *       The first time, mddev->raid_disks will be 0, and data from
 641  *       dev should be merged in.  Subsequent calls check that dev
 642  *       is new enough.  Return 0 or -EINVAL
 643  *
 644  *   void sync_super(mddev_t *mddev, mdk_rdev_t *dev)
 645  *     Update the superblock for rdev with data in mddev
 646  *     This does not write to disc.
 647  *
 648  */
 649
 650 struct super_type  {
 651         char                *name;
 652         struct module       *owner;
 653         int                 (*load_super)(mdk_rdev_t *rdev, mdk_rdev_t *refdev,
 654                                           int minor_version);
 655         int                 (*validate_super)(mddev_t *mddev, mdk_rdev_t *rdev);
 656         void                (*sync_super)(mddev_t *mddev, mdk_rdev_t *rdev);
 657         unsigned long long  (*rdev_size_change)(mdk_rdev_t *rdev,
 658                                                 sector_t num_sectors);
 659 };
 660
 661 /*
 662  * load_super for 0.90.0
 663  */
 664 static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
 665 {
 666         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
 667         mdp_super_t *sb;
 668         int ret;
 669
 670         /*
 671          * Calculate the position of the superblock (512byte sectors),
 672          * it's at the end of the disk.
 673          *
 674          * It also happens to be a multiple of 4Kb.
 675          */
 676         rdev->sb_start = calc_dev_sboffset(rdev->bdev);
 677
 678         ret = read_disk_sb(rdev, MD_SB_BYTES);
 679         if (ret) return ret;
 680
 681         ret = -EINVAL;
 682
 683         bdevname(rdev->bdev, b);
 684         sb = (mdp_super_t*)page_address(rdev->sb_page);
 685
 686         if (sb->md_magic != MD_SB_MAGIC) {
 687                 printk(KERN_ERR "md: invalid raid superblock magic on %s\n",
 688                        b);
 689                 goto abort;
 690         }
 691
 692         if (sb->major_version != 0 ||
 693             sb->minor_version < 90 ||
 694             sb->minor_version > 91) {
 695                 printk(KERN_WARNING "Bad version number %d.%d on %s\n",
 696                         sb->major_version, sb->minor_version,
 697                         b);
 698                 goto abort;
 699         }
 700
 701         if (sb->raid_disks <= 0)
 702                 goto abort;
 703
 704         if (md_csum_fold(calc_sb_csum(sb)) != md_csum_fold(sb->sb_csum)) {
 705                 printk(KERN_WARNING "md: invalid superblock checksum on %s\n",
 706                         b);
 707                 goto abort;
 708         }
 709
 710         rdev->preferred_minor = sb->md_minor;
 711         rdev->data_offset = 0;
 712         rdev->sb_size = MD_SB_BYTES;
 713
 714         if (sb->state & (1<<MD_SB_BITMAP_PRESENT)) {
 715                 if (sb->level != 1 && sb->level != 4
 716                     && sb->level != 5 && sb->level != 6
 717                     && sb->level != 10) {
 718                         /* FIXME use a better test */
 719                         printk(KERN_WARNING
 720                                "md: bitmaps not supported for this level.\n");
 721                         goto abort;
 722                 }
 723         }
 724
 725         if (sb->level == LEVEL_MULTIPATH)
 726                 rdev->desc_nr = -1;
 727         else
 728                 rdev->desc_nr = sb->this_disk.number;
 729
 730         if (!refdev) {
 731                 ret = 1;
 732         } else {
 733                 __u64 ev1, ev2;
 734                 mdp_super_t *refsb = (mdp_super_t*)page_address(refdev->sb_page);
 735                 if (!uuid_equal(refsb, sb)) {
 736                         printk(KERN_WARNING "md: %s has different UUID to %s\n",
 737                                 b, bdevname(refdev->bdev,b2));
 738                         goto abort;
 739                 }
 740                 if (!sb_equal(refsb, sb)) {
 741                         printk(KERN_WARNING "md: %s has same UUID"
 742                                " but different superblock to %s\n",
 743                                b, bdevname(refdev->bdev, b2));
 744                         goto abort;
 745                 }
 746                 ev1 = md_event(sb);
 747                 ev2 = md_event(refsb);
 748                 if (ev1 > ev2)
 749                         ret = 1;
 750                 else
 751                         ret = 0;
 752         }
 753         rdev->size = calc_num_sectors(rdev, sb->chunk_size) / 2;
 754
 755         if (rdev->size < sb->size && sb->level > 1)
 756                 /* "this cannot possibly happen" ... */
 757                 ret = -EINVAL;
 758
 759  abort:
 760         return ret;
 761 }
 762
 763 /*
 764  * validate_super for 0.90.0
 765  */
 766 static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
 767 {
 768         mdp_disk_t *desc;
 769         mdp_super_t *sb = (mdp_super_t *)page_address(rdev->sb_page);
 770         __u64 ev1 = md_event(sb);
 771
 772         rdev->raid_disk = -1;
 773         clear_bit(Faulty, &rdev->flags);
 774         clear_bit(In_sync, &rdev->flags);
 775         clear_bit(WriteMostly, &rdev->flags);
 776         clear_bit(BarriersNotsupp, &rdev->flags);
 777
 778         if (mddev->raid_disks == 0) {
 779                 mddev->major_version = 0;
 780                 mddev->minor_version = sb->minor_version;
 781                 mddev->patch_version = sb->patch_version;
 782                 mddev->external = 0;
 783                 mddev->chunk_size = sb->chunk_size;
 784                 mddev->ctime = sb->ctime;
 785                 mddev->utime = sb->utime;
 786                 mddev->level = sb->level;
 787                 mddev->clevel[0] = 0;
 788                 mddev->layout = sb->layout;
 789                 mddev->raid_disks = sb->raid_disks;
 790                 mddev->size = sb->size;
 791                 mddev->events = ev1;
 792                 mddev->bitmap_offset = 0;
 793                 mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
 794
 795                 if (mddev->minor_version >= 91) {
 796                         mddev->reshape_position = sb->reshape_position;
 797                         mddev->delta_disks = sb->delta_disks;
 798                         mddev->new_level = sb->new_level;
 799                         mddev->new_layout = sb->new_layout;
 800                         mddev->new_chunk = sb->new_chunk;
 801                 } else {
 802                         mddev->reshape_position = MaxSector;
 803                         mddev->delta_disks = 0;
 804                         mddev->new_level = mddev->level;
 805                         mddev->new_layout = mddev->layout;
 806                         mddev->new_chunk = mddev->chunk_size;
 807                 }
 808
 809                 if (sb->state & (1<<MD_SB_CLEAN))
 810                         mddev->recovery_cp = MaxSector;
 811                 else {
 812                         if (sb->events_hi == sb->cp_events_hi &&
 813                                 sb->events_lo == sb->cp_events_lo) {
 814                                 mddev->recovery_cp = sb->recovery_cp;
 815                         } else
 816                                 mddev->recovery_cp = 0;
 817                 }
 818
 819                 memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
 820                 memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
 821                 memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
 822                 memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
 823
 824                 mddev->max_disks = MD_SB_DISKS;
 825
 826                 if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
 827                     mddev->bitmap_file == NULL)
 828                         mddev->bitmap_offset = mddev->default_bitmap_offset;
 829
 830         } else if (mddev->pers == NULL) {
 831                 /* Insist on good event counter while assembling */
 832                 ++ev1;
 833                 if (ev1 < mddev->events)
 834                         return -EINVAL;
 835         } else if (mddev->bitmap) {
 836                 /* if adding to array with a bitmap, then we can accept an
 837                  * older device ... but not too old.
 838                  */
 839                 if (ev1 < mddev->bitmap->events_cleared)
 840                         return 0;
 841         } else {
 842                 if (ev1 < mddev->events)
 843                         /* just a hot-add of a new device, leave raid_disk at -1 */
 844                         return 0;
 845         }
 846
 847         if (mddev->level != LEVEL_MULTIPATH) {
 848                 desc = sb->disks + rdev->desc_nr;
 849
 850                 if (desc->state & (1<<MD_DISK_FAULTY))
 851                         set_bit(Faulty, &rdev->flags);
 852                 else if (desc->state & (1<<MD_DISK_SYNC) /* &&
 853                             desc->raid_disk < mddev->raid_disks */) {
 854                         set_bit(In_sync, &rdev->flags);
 855                         rdev->raid_disk = desc->raid_disk;
 856                 }
 857                 if (desc->state & (1<<MD_DISK_WRITEMOSTLY))
 858                         set_bit(WriteMostly, &rdev->flags);
 859         } else /* MULTIPATH are always insync */
 860                 set_bit(In_sync, &rdev->flags);
 861         return 0;
 862 }
 863
 864 /*
 865  * sync_super for 0.90.0
 866  */
 867 static void super_90_sync(mddev_t *mddev, mdk_rdev_t *rdev)
 868 {
 869         mdp_super_t *sb;
 870         struct list_head *tmp;
 871         mdk_rdev_t *rdev2;
 872         int next_spare = mddev->raid_disks;
 873
 874
 875         /* make rdev->sb match mddev data..
 876          *
 877          * 1/ zero out disks
 878          * 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
 879          * 3/ any empty disks < next_spare become removed
 880          *
 881          * disks[0] gets initialised to REMOVED because
 882          * we cannot be sure from other fields if it has
 883          * been initialised or not.
 884          */
 885         int i;
 886         int active=0, working=0,failed=0,spare=0,nr_disks=0;
 887
 888         rdev->sb_size = MD_SB_BYTES;
 889
 890         sb = (mdp_super_t*)page_address(rdev->sb_page);
 891
 892         memset(sb, 0, sizeof(*sb));
 893
 894         sb->md_magic = MD_SB_MAGIC;
 895         sb->major_version = mddev->major_version;
 896         sb->patch_version = mddev->patch_version;
 897         sb->gvalid_words  = 0; /* ignored */
 898         memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
 899         memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
 900         memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
 901         memcpy(&sb->set_uuid3, mddev->uuid+12,4);
 902
 903         sb->ctime = mddev->ctime;
 904         sb->level = mddev->level;
 905         sb->size  = mddev->size;
 906         sb->raid_disks = mddev->raid_disks;
 907         sb->md_minor = mddev->md_minor;
 908         sb->not_persistent = 0;
 909         sb->utime = mddev->utime;
 910         sb->state = 0;
 911         sb->events_hi = (mddev->events>>32);
 912         sb->events_lo = (u32)mddev->events;
 913
 914         if (mddev->reshape_position == MaxSector)
 915                 sb->minor_version = 90;
 916         else {
 917                 sb->minor_version = 91;
 918                 sb->reshape_position = mddev->reshape_position;
 919                 sb->new_level = mddev->new_level;
 920                 sb->delta_disks = mddev->delta_disks;
 921                 sb->new_layout = mddev->new_layout;
 922                 sb->new_chunk = mddev->new_chunk;
 923         }
 924         mddev->minor_version = sb->minor_version;
 925         if (mddev->in_sync)
 926         {
 927                 sb->recovery_cp = mddev->recovery_cp;
 928                 sb->cp_events_hi = (mddev->events>>32);
 929                 sb->cp_events_lo = (u32)mddev->events;
 930                 if (mddev->recovery_cp == MaxSector)
 931                         sb->state = (1<< MD_SB_CLEAN);
 932         } else
 933                 sb->recovery_cp = 0;
 934
 935         sb->layout = mddev->layout;
 936         sb->chunk_size = mddev->chunk_size;
 937
 938         if (mddev->bitmap && mddev->bitmap_file == NULL)
 939                 sb->state |= (1<<MD_SB_BITMAP_PRESENT);
 940
 941         sb->disks[0].state = (1<<MD_DISK_REMOVED);
 942         rdev_for_each(rdev2, tmp, mddev) {
 943                 mdp_disk_t *d;
 944                 int desc_nr;
 945                 if (rdev2->raid_disk >= 0 && test_bit(In_sync, &rdev2->flags)
 946                     && !test_bit(Faulty, &rdev2->flags))
 947                         desc_nr = rdev2->raid_disk;
 948                 else
 949                         desc_nr = next_spare++;
 950                 rdev2->desc_nr = desc_nr;
 951                 d = &sb->disks[rdev2->desc_nr];
 952                 nr_disks++;
 953                 d->number = rdev2->desc_nr;
 954                 d->major = MAJOR(rdev2->bdev->bd_dev);
 955                 d->minor = MINOR(rdev2->bdev->bd_dev);
 956                 if (rdev2->raid_disk >= 0 && test_bit(In_sync, &rdev2->flags)
 957                     && !test_bit(Faulty, &rdev2->flags))
 958                         d->raid_disk = rdev2->raid_disk;
 959                 else
 960                         d->raid_disk = rdev2->desc_nr; /* compatibility */
 961                 if (test_bit(Faulty, &rdev2->flags))
 962                         d->state = (1<<MD_DISK_FAULTY);
 963                 else if (test_bit(In_sync, &rdev2->flags)) {
 964                         d->state = (1<<MD_DISK_ACTIVE);
 965                         d->state |= (1<<MD_DISK_SYNC);
 966                         active++;
 967                         working++;
 968                 } else {
 969                         d->state = 0;
 970                         spare++;
 971                         working++;
 972                 }
 973                 if (test_bit(WriteMostly, &rdev2->flags))
 974                         d->state |= (1<<MD_DISK_WRITEMOSTLY);
 975         }
 976         /* now set the "removed" and "faulty" bits on any missing devices */
 977         for (i=0 ; i < mddev->raid_disks ; i++) {
 978                 mdp_disk_t *d = &sb->disks[i];
 979                 if (d->state == 0 && d->number == 0) {
 980                         d->number = i;
 981                         d->raid_disk = i;
 982                         d->state = (1<<MD_DISK_REMOVED);
 983                         d->state |= (1<<MD_DISK_FAULTY);
 984                         failed++;
 985                 }
 986         }
 987         sb->nr_disks = nr_disks;
 988         sb->active_disks = active;
 989         sb->working_disks = working;
 990         sb->failed_disks = failed;
 991         sb->spare_disks = spare;
 992
 993         sb->this_disk = sb->disks[rdev->desc_nr];
 994         sb->sb_csum = calc_sb_csum(sb);
 995 }
 996
 997 /*
 998  * rdev_size_change for 0.90.0
 999  */
1000 static unsigned long long
1001 super_90_rdev_size_change(mdk_rdev_t *rdev, sector_t num_sectors)
1002 {
1003         if (num_sectors && num_sectors < rdev->mddev->size * 2)
1004                 return 0; /* component must fit device */
1005         if (rdev->mddev->bitmap_offset)
1006                 return 0; /* can't move bitmap */
1007         rdev->sb_start = calc_dev_sboffset(rdev->bdev);
1008         if (!num_sectors || num_sectors > rdev->sb_start)
1009                 num_sectors = rdev->sb_start;
1010         md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
1011                        rdev->sb_page);
1012         md_super_wait(rdev->mddev);
1013         return num_sectors / 2; /* kB for sysfs */
1014 }
1015
1016
1017 /*
1018  * version 1 superblock
1019  */
1020
1021 static __le32 calc_sb_1_csum(struct mdp_superblock_1 * sb)
1022 {
1023         __le32 disk_csum;
1024         u32 csum;
1025         unsigned long long newcsum;
1026         int size = 256 + le32_to_cpu(sb->max_dev)*2;
1027         __le32 *isuper = (__le32*)sb;
1028         int i;
1029
1030         disk_csum = sb->sb_csum;
1031         sb->sb_csum = 0;
1032         newcsum = 0;
1033         for (i=0; size>=4; size -= 4 )
1034                 newcsum += le32_to_cpu(*isuper++);
1035
1036         if (size == 2)
1037                 newcsum += le16_to_cpu(*(__le16*) isuper);
1038
1039         csum = (newcsum & 0xffffffff) + (newcsum >> 32);
1040         sb->sb_csum = disk_csum;
1041         return cpu_to_le32(csum);
1042 }
1043
1044 static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
1045 {
1046         struct mdp_superblock_1 *sb;
1047         int ret;
1048         sector_t sb_start;
1049         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1050         int bmask;
1051
1052         /*
1053          * Calculate the position of the superblock in 512byte sectors.
1054          * It is always aligned to a 4K boundary and
1055          * depeding on minor_version, it can be:
1056          * 0: At least 8K, but less than 12K, from end of device
1057          * 1: At start of device
1058          * 2: 4K from start of device.
1059          */
1060         switch(minor_version) {
1061         case 0:
1062                 sb_start = rdev->bdev->bd_inode->i_size >> 9;
1063                 sb_start -= 8*2;
1064                 sb_start &= ~(sector_t)(4*2-1);
1065                 break;
1066         case 1:
1067                 sb_start = 0;
1068                 break;
1069         case 2:
1070                 sb_start = 8;
1071                 break;
1072         default:
1073                 return -EINVAL;
1074         }
1075         rdev->sb_start = sb_start;
1076
1077         /* superblock is rarely larger than 1K, but it can be larger,
1078          * and it is safe to read 4k, so we do that
1079          */
1080         ret = read_disk_sb(rdev, 4096);
1081         if (ret) return ret;
1082
1083
1084         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1085
1086         if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
1087             sb->major_version != cpu_to_le32(1) ||
1088             le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
1089             le64_to_cpu(sb->super_offset) != rdev->sb_start ||
1090             (le32_to_cpu(sb->feature_map) & ~MD_FEATURE_ALL) != 0)
1091                 return -EINVAL;
1092
1093         if (calc_sb_1_csum(sb) != sb->sb_csum) {
1094                 printk("md: invalid superblock checksum on %s\n",
1095                         bdevname(rdev->bdev,b));
1096                 return -EINVAL;
1097         }
1098         if (le64_to_cpu(sb->data_size) < 10) {
1099                 printk("md: data_size too small on %s\n",
1100                        bdevname(rdev->bdev,b));
1101                 return -EINVAL;
1102         }
1103         if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET)) {
1104                 if (sb->level != cpu_to_le32(1) &&
1105                     sb->level != cpu_to_le32(4) &&
1106                     sb->level != cpu_to_le32(5) &&
1107                     sb->level != cpu_to_le32(6) &&
1108                     sb->level != cpu_to_le32(10)) {
1109                         printk(KERN_WARNING
1110                                "md: bitmaps not supported for this level.\n");
1111                         return -EINVAL;
1112                 }
1113         }
1114
1115         rdev->preferred_minor = 0xffff;
1116         rdev->data_offset = le64_to_cpu(sb->data_offset);
1117         atomic_set(&rdev->corrected_errors, le32_to_cpu(sb->cnt_corrected_read));
1118
1119         rdev->sb_size = le32_to_cpu(sb->max_dev) * 2 + 256;
1120         bmask = queue_hardsect_size(rdev->bdev->bd_disk->queue)-1;
1121         if (rdev->sb_size & bmask)
1122                 rdev->sb_size = (rdev->sb_size | bmask) + 1;
1123
1124         if (minor_version
1125             && rdev->data_offset < sb_start + (rdev->sb_size/512))
1126                 return -EINVAL;
1127
1128         if (sb->level == cpu_to_le32(LEVEL_MULTIPATH))
1129                 rdev->desc_nr = -1;
1130         else
1131                 rdev->desc_nr = le32_to_cpu(sb->dev_number);
1132
1133         if (!refdev) {
1134                 ret = 1;
1135         } else {
1136                 __u64 ev1, ev2;
1137                 struct mdp_superblock_1 *refsb =
1138                         (struct mdp_superblock_1*)page_address(refdev->sb_page);
1139
1140                 if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
1141                     sb->level != refsb->level ||
1142                     sb->layout != refsb->layout ||
1143                     sb->chunksize != refsb->chunksize) {
1144                         printk(KERN_WARNING "md: %s has strangely different"
1145                                 " superblock to %s\n",
1146                                 bdevname(rdev->bdev,b),
1147                                 bdevname(refdev->bdev,b2));
1148                         return -EINVAL;
1149                 }
1150                 ev1 = le64_to_cpu(sb->events);
1151                 ev2 = le64_to_cpu(refsb->events);
1152
1153                 if (ev1 > ev2)
1154                         ret = 1;
1155                 else
1156                         ret = 0;
1157         }
1158         if (minor_version)
1159                 rdev->size = ((rdev->bdev->bd_inode->i_size>>9) - le64_to_cpu(sb->data_offset)) / 2;
1160         else
1161                 rdev->size = rdev->sb_start / 2;
1162         if (rdev->size < le64_to_cpu(sb->data_size)/2)
1163                 return -EINVAL;
1164         rdev->size = le64_to_cpu(sb->data_size)/2;
1165         if (le32_to_cpu(sb->chunksize))
1166                 rdev->size &= ~((sector_t)le32_to_cpu(sb->chunksize)/2 - 1);
1167
1168         if (le64_to_cpu(sb->size) > rdev->size*2)
1169                 return -EINVAL;
1170         return ret;
1171 }
1172
1173 static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
1174 {
1175         struct mdp_superblock_1 *sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1176         __u64 ev1 = le64_to_cpu(sb->events);
1177
1178         rdev->raid_disk = -1;
1179         clear_bit(Faulty, &rdev->flags);
1180         clear_bit(In_sync, &rdev->flags);
1181         clear_bit(WriteMostly, &rdev->flags);
1182         clear_bit(BarriersNotsupp, &rdev->flags);
1183
1184         if (mddev->raid_disks == 0) {
1185                 mddev->major_version = 1;
1186                 mddev->patch_version = 0;
1187                 mddev->external = 0;
1188                 mddev->chunk_size = le32_to_cpu(sb->chunksize) << 9;
1189                 mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);
1190                 mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);
1191                 mddev->level = le32_to_cpu(sb->level);
1192                 mddev->clevel[0] = 0;
1193                 mddev->layout = le32_to_cpu(sb->layout);
1194                 mddev->raid_disks = le32_to_cpu(sb->raid_disks);
1195                 mddev->size = le64_to_cpu(sb->size)/2;
1196                 mddev->events = ev1;
1197                 mddev->bitmap_offset = 0;
1198                 mddev->default_bitmap_offset = 1024 >> 9;
1199
1200                 mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
1201                 memcpy(mddev->uuid, sb->set_uuid, 16);
1202
1203                 mddev->max_disks =  (4096-256)/2;
1204
1205                 if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET) &&
1206                     mddev->bitmap_file == NULL )
1207                         mddev->bitmap_offset = (__s32)le32_to_cpu(sb->bitmap_offset);
1208
1209                 if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE)) {
1210                         mddev->reshape_position = le64_to_cpu(sb->reshape_position);
1211                         mddev->delta_disks = le32_to_cpu(sb->delta_disks);
1212                         mddev->new_level = le32_to_cpu(sb->new_level);
1213                         mddev->new_layout = le32_to_cpu(sb->new_layout);
1214                         mddev->new_chunk = le32_to_cpu(sb->new_chunk)<<9;
1215                 } else {
1216                         mddev->reshape_position = MaxSector;
1217                         mddev->delta_disks = 0;
1218                         mddev->new_level = mddev->level;
1219                         mddev->new_layout = mddev->layout;
1220                         mddev->new_chunk = mddev->chunk_size;
1221                 }
1222
1223         } else if (mddev->pers == NULL) {
1224                 /* Insist of good event counter while assembling */
1225                 ++ev1;
1226                 if (ev1 < mddev->events)
1227                         return -EINVAL;
1228         } else if (mddev->bitmap) {
1229                 /* If adding to array with a bitmap, then we can accept an
1230                  * older device, but not too old.
1231                  */
1232                 if (ev1 < mddev->bitmap->events_cleared)
1233                         return 0;
1234         } else {
1235                 if (ev1 < mddev->events)
1236                         /* just a hot-add of a new device, leave raid_disk at -1 */
1237                         return 0;
1238         }
1239         if (mddev->level != LEVEL_MULTIPATH) {
1240                 int role;
1241                 role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
1242                 switch(role) {
1243                 case 0xffff: /* spare */
1244                         break;
1245                 case 0xfffe: /* faulty */
1246                         set_bit(Faulty, &rdev->flags);
1247                         break;
1248                 default:
1249                         if ((le32_to_cpu(sb->feature_map) &
1250                              MD_FEATURE_RECOVERY_OFFSET))
1251                                 rdev->recovery_offset = le64_to_cpu(sb->recovery_offset);
1252                         else
1253                                 set_bit(In_sync, &rdev->flags);
1254                         rdev->raid_disk = role;
1255                         break;
1256                 }
1257                 if (sb->devflags & WriteMostly1)
1258                         set_bit(WriteMostly, &rdev->flags);
1259         } else /* MULTIPATH are always insync */
1260                 set_bit(In_sync, &rdev->flags);
1261
1262         return 0;
1263 }
1264
1265 static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
1266 {
1267         struct mdp_superblock_1 *sb;
1268         struct list_head *tmp;
1269         mdk_rdev_t *rdev2;
1270         int max_dev, i;
1271         /* make rdev->sb match mddev and rdev data. */
1272
1273         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1274
1275         sb->feature_map = 0;
1276         sb->pad0 = 0;
1277         sb->recovery_offset = cpu_to_le64(0);
1278         memset(sb->pad1, 0, sizeof(sb->pad1));
1279         memset(sb->pad2, 0, sizeof(sb->pad2));
1280         memset(sb->pad3, 0, sizeof(sb->pad3));
1281
1282         sb->utime = cpu_to_le64((__u64)mddev->utime);
1283         sb->events = cpu_to_le64(mddev->events);
1284         if (mddev->in_sync)
1285                 sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
1286         else
1287                 sb->resync_offset = cpu_to_le64(0);
1288
1289         sb->cnt_corrected_read = cpu_to_le32(atomic_read(&rdev->corrected_errors));
1290
1291         sb->raid_disks = cpu_to_le32(mddev->raid_disks);
1292         sb->size = cpu_to_le64(mddev->size<<1);
1293
1294         if (mddev->bitmap && mddev->bitmap_file == NULL) {
1295                 sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_offset);
1296                 sb->feature_map = cpu_to_le32(MD_FEATURE_BITMAP_OFFSET);
1297         }
1298
1299         if (rdev->raid_disk >= 0 &&
1300             !test_bit(In_sync, &rdev->flags) &&
1301             rdev->recovery_offset > 0) {
1302                 sb->feature_map |= cpu_to_le32(MD_FEATURE_RECOVERY_OFFSET);
1303                 sb->recovery_offset = cpu_to_le64(rdev->recovery_offset);
1304         }
1305
1306         if (mddev->reshape_position != MaxSector) {
1307                 sb->feature_map |= cpu_to_le32(MD_FEATURE_RESHAPE_ACTIVE);
1308                 sb->reshape_position = cpu_to_le64(mddev->reshape_position);
1309                 sb->new_layout = cpu_to_le32(mddev->new_layout);
1310                 sb->delta_disks = cpu_to_le32(mddev->delta_disks);
1311                 sb->new_level = cpu_to_le32(mddev->new_level);
1312                 sb->new_chunk = cpu_to_le32(mddev->new_chunk>>9);
1313         }
1314
1315         max_dev = 0;
1316         rdev_for_each(rdev2, tmp, mddev)
1317                 if (rdev2->desc_nr+1 > max_dev)
1318                         max_dev = rdev2->desc_nr+1;
1319
1320         if (max_dev > le32_to_cpu(sb->max_dev))
1321                 sb->max_dev = cpu_to_le32(max_dev);
1322         for (i=0; i<max_dev;i++)
1323                 sb->dev_roles[i] = cpu_to_le16(0xfffe);
1324
1325         rdev_for_each(rdev2, tmp, mddev) {
1326                 i = rdev2->desc_nr;
1327                 if (test_bit(Faulty, &rdev2->flags))
1328                         sb->dev_roles[i] = cpu_to_le16(0xfffe);
1329                 else if (test_bit(In_sync, &rdev2->flags))
1330                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1331                 else if (rdev2->raid_disk >= 0 && rdev2->recovery_offset > 0)
1332                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1333                 else
1334                         sb->dev_roles[i] = cpu_to_le16(0xffff);
1335         }
1336
1337         sb->sb_csum = calc_sb_1_csum(sb);
1338 }
1339
1340 static unsigned long long
1341 super_1_rdev_size_change(mdk_rdev_t *rdev, sector_t num_sectors)
1342 {
1343         struct mdp_superblock_1 *sb;
1344         sector_t max_sectors;
1345         if (num_sectors && num_sectors < rdev->mddev->size * 2)
1346                 return 0; /* component must fit device */
1347         if (rdev->sb_start < rdev->data_offset) {
1348                 /* minor versions 1 and 2; superblock before data */
1349                 max_sectors = rdev->bdev->bd_inode->i_size >> 9;
1350                 max_sectors -= rdev->data_offset;
1351                 if (!num_sectors || num_sectors > max_sectors)
1352                         num_sectors = max_sectors;
1353         } else if (rdev->mddev->bitmap_offset) {
1354                 /* minor version 0 with bitmap we can't move */
1355                 return 0;
1356         } else {
1357                 /* minor version 0; superblock after data */
1358                 sector_t sb_start;
1359                 sb_start = (rdev->bdev->bd_inode->i_size >> 9) - 8*2;
1360                 sb_start &= ~(sector_t)(4*2 - 1);
1361                 max_sectors = rdev->size * 2 + sb_start - rdev->sb_start;
1362                 if (!num_sectors || num_sectors > max_sectors)
1363                         num_sectors = max_sectors;
1364                 rdev->sb_start = sb_start;
1365         }
1366         sb = (struct mdp_superblock_1 *) page_address(rdev->sb_page);
1367         sb->data_size = cpu_to_le64(num_sectors);
1368         sb->super_offset = rdev->sb_start;
1369         sb->sb_csum = calc_sb_1_csum(sb);
1370         md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
1371                        rdev->sb_page);
1372         md_super_wait(rdev->mddev);
1373         return num_sectors / 2; /* kB for sysfs */
1374 }
1375
1376 static struct super_type super_types[] = {
1377         [0] = {
1378                 .name   = "0.90.0",
1379                 .owner  = THIS_MODULE,
1380                 .load_super         = super_90_load,
1381                 .validate_super     = super_90_validate,
1382                 .sync_super         = super_90_sync,
1383                 .rdev_size_change   = super_90_rdev_size_change,
1384         },
1385         [1] = {
1386                 .name   = "md-1",
1387                 .owner  = THIS_MODULE,
1388                 .load_super         = super_1_load,
1389                 .validate_super     = super_1_validate,
1390                 .sync_super         = super_1_sync,
1391                 .rdev_size_change   = super_1_rdev_size_change,
1392         },
1393 };
1394
1395 static int match_mddev_units(mddev_t *mddev1, mddev_t *mddev2)
1396 {
1397         struct list_head *tmp, *tmp2;
1398         mdk_rdev_t *rdev, *rdev2;
1399
1400         rdev_for_each(rdev, tmp, mddev1)
1401                 rdev_for_each(rdev2, tmp2, mddev2)
1402                         if (rdev->bdev->bd_contains ==
1403                             rdev2->bdev->bd_contains)
1404                                 return 1;
1405
1406         return 0;
1407 }
1408
1409 static LIST_HEAD(pending_raid_disks);
1410
1411 static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
1412 {
1413         char b[BDEVNAME_SIZE];
1414         struct kobject *ko;
1415         char *s;
1416         int err;
1417
1418         if (rdev->mddev) {
1419                 MD_BUG();
1420                 return -EINVAL;
1421         }
1422
1423         /* prevent duplicates */
1424         if (find_rdev(mddev, rdev->bdev->bd_dev))
1425                 return -EEXIST;
1426
1427         /* make sure rdev->size exceeds mddev->size */
1428         if (rdev->size && (mddev->size == 0 || rdev->size < mddev->size)) {
1429                 if (mddev->pers) {
1430                         /* Cannot change size, so fail
1431                          * If mddev->level <= 0, then we don't care
1432                          * about aligning sizes (e.g. linear)
1433                          */
1434                         if (mddev->level > 0)
1435                                 return -ENOSPC;
1436                 } else
1437                         mddev->size = rdev->size;
1438         }
1439
1440         /* Verify rdev->desc_nr is unique.
1441          * If it is -1, assign a free number, else
1442          * check number is not in use
1443          */
1444         if (rdev->desc_nr < 0) {
1445                 int choice = 0;
1446                 if (mddev->pers) choice = mddev->raid_disks;
1447                 while (find_rdev_nr(mddev, choice))
1448                         choice++;
1449                 rdev->desc_nr = choice;
1450         } else {
1451                 if (find_rdev_nr(mddev, rdev->desc_nr))
1452                         return -EBUSY;
1453         }
1454         bdevname(rdev->bdev,b);
1455         while ( (s=strchr(b, '/')) != NULL)
1456                 *s = '!';
1457
1458         rdev->mddev = mddev;
1459         printk(KERN_INFO "md: bind<%s>\n", b);
1460
1461         if ((err = kobject_add(&rdev->kobj, &mddev->kobj, "dev-%s", b)))
1462                 goto fail;
1463
1464         if (rdev->bdev->bd_part)
1465                 ko = &rdev->bdev->bd_part->dev.kobj;
1466         else
1467                 ko = &rdev->bdev->bd_disk->dev.kobj;
1468         if ((err = sysfs_create_link(&rdev->kobj, ko, "block"))) {
1469                 kobject_del(&rdev->kobj);
1470                 goto fail;
1471         }
1472         list_add(&rdev->same_set, &mddev->disks);
1473         bd_claim_by_disk(rdev->bdev, rdev->bdev->bd_holder, mddev->gendisk);
1474         return 0;
1475
1476  fail:
1477         printk(KERN_WARNING "md: failed to register dev-%s for %s\n",
1478                b, mdname(mddev));
1479         return err;
1480 }
1481
1482 static void md_delayed_delete(struct work_struct *ws)
1483 {
1484         mdk_rdev_t *rdev = container_of(ws, mdk_rdev_t, del_work);
1485         kobject_del(&rdev->kobj);
1486         kobject_put(&rdev->kobj);
1487 }
1488
1489 static void unbind_rdev_from_array(mdk_rdev_t * rdev)
1490 {
1491         char b[BDEVNAME_SIZE];
1492         if (!rdev->mddev) {
1493                 MD_BUG();
1494                 return;
1495         }
1496         bd_release_from_disk(rdev->bdev, rdev->mddev->gendisk);
1497         list_del_init(&rdev->same_set);
1498         printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
1499         rdev->mddev = NULL;
1500         sysfs_remove_link(&rdev->kobj, "block");
1501
1502         /* We need to delay this, otherwise we can deadlock when
1503          * writing to 'remove' to "dev/state"
1504          */
1505         INIT_WORK(&rdev->del_work, md_delayed_delete);
1506         kobject_get(&rdev->kobj);
1507         schedule_work(&rdev->del_work);
1508 }
1509
1510 /*
1511  * prevent the device from being mounted, repartitioned or
1512  * otherwise reused by a RAID array (or any other kernel
1513  * subsystem), by bd_claiming the device.
1514  */
1515 static int lock_rdev(mdk_rdev_t *rdev, dev_t dev, int shared)
1516 {
1517         int err = 0;
1518         struct block_device *bdev;
1519         char b[BDEVNAME_SIZE];
1520
1521         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
1522         if (IS_ERR(bdev)) {
1523                 printk(KERN_ERR "md: could not open %s.\n",
1524                         __bdevname(dev, b));
1525                 return PTR_ERR(bdev);
1526         }
1527         err = bd_claim(bdev, shared ? (mdk_rdev_t *)lock_rdev : rdev);
1528         if (err) {
1529                 printk(KERN_ERR "md: could not bd_claim %s.\n",
1530                         bdevname(bdev, b));
1531                 blkdev_put(bdev);
1532                 return err;
1533         }
1534         if (!shared)
1535                 set_bit(AllReserved, &rdev->flags);
1536         rdev->bdev = bdev;
1537         return err;
1538 }
1539
1540 static void unlock_rdev(mdk_rdev_t *rdev)
1541 {
1542         struct block_device *bdev = rdev->bdev;
1543         rdev->bdev = NULL;
1544         if (!bdev)
1545                 MD_BUG();
1546         bd_release(bdev);
1547         blkdev_put(bdev);
1548 }
1549
1550 void md_autodetect_dev(dev_t dev);
1551
1552 static void export_rdev(mdk_rdev_t * rdev)
1553 {
1554         char b[BDEVNAME_SIZE];
1555         printk(KERN_INFO "md: export_rdev(%s)\n",
1556                 bdevname(rdev->bdev,b));
1557         if (rdev->mddev)
1558                 MD_BUG();
1559         free_disk_sb(rdev);
1560         list_del_init(&rdev->same_set);
1561 #ifndef MODULE
1562         if (test_bit(AutoDetected, &rdev->flags))
1563                 md_autodetect_dev(rdev->bdev->bd_dev);
1564 #endif
1565         unlock_rdev(rdev);
1566         kobject_put(&rdev->kobj);
1567 }
1568
1569 static void kick_rdev_from_array(mdk_rdev_t * rdev)
1570 {
1571         unbind_rdev_from_array(rdev);
1572         export_rdev(rdev);
1573 }
1574
1575 static void export_array(mddev_t *mddev)
1576 {
1577         struct list_head *tmp;
1578         mdk_rdev_t *rdev;
1579
1580         rdev_for_each(rdev, tmp, mddev) {
1581                 if (!rdev->mddev) {
1582                         MD_BUG();
1583                         continue;
1584                 }
1585                 kick_rdev_from_array(rdev);
1586         }
1587         if (!list_empty(&mddev->disks))
1588                 MD_BUG();
1589         mddev->raid_disks = 0;
1590         mddev->major_version = 0;
1591 }
1592
1593 static void print_desc(mdp_disk_t *desc)
1594 {
1595         printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
1596                 desc->major,desc->minor,desc->raid_disk,desc->state);
1597 }
1598
1599 static void print_sb(mdp_super_t *sb)
1600 {
1601         int i;
1602
1603         printk(KERN_INFO
1604                 "md:  SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
1605                 sb->major_version, sb->minor_version, sb->patch_version,
1606                 sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
1607                 sb->ctime);
1608         printk(KERN_INFO "md:     L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
1609                 sb->level, sb->size, sb->nr_disks, sb->raid_disks,
1610                 sb->md_minor, sb->layout, sb->chunk_size);
1611         printk(KERN_INFO "md:     UT:%08x ST:%d AD:%d WD:%d"
1612                 " FD:%d SD:%d CSUM:%08x E:%08lx\n",
1613                 sb->utime, sb->state, sb->active_disks, sb->working_disks,
1614                 sb->failed_disks, sb->spare_disks,
1615                 sb->sb_csum, (unsigned long)sb->events_lo);
1616
1617         printk(KERN_INFO);
1618         for (i = 0; i < MD_SB_DISKS; i++) {
1619                 mdp_disk_t *desc;
1620
1621                 desc = sb->disks + i;
1622                 if (desc->number || desc->major || desc->minor ||
1623                     desc->raid_disk || (desc->state && (desc->state != 4))) {
1624                         printk("     D %2d: ", i);
1625                         print_desc(desc);
1626                 }
1627         }
1628         printk(KERN_INFO "md:     THIS: ");
1629         print_desc(&sb->this_disk);
1630
1631 }
1632
1633 static void print_rdev(mdk_rdev_t *rdev)
1634 {
1635         char b[BDEVNAME_SIZE];
1636         printk(KERN_INFO "md: rdev %s, SZ:%08llu F:%d S:%d DN:%u\n",
1637                 bdevname(rdev->bdev,b), (unsigned long long)rdev->size,
1638                 test_bit(Faulty, &rdev->flags), test_bit(In_sync, &rdev->flags),
1639                 rdev->desc_nr);
1640         if (rdev->sb_loaded) {
1641                 printk(KERN_INFO "md: rdev superblock:\n");
1642                 print_sb((mdp_super_t*)page_address(rdev->sb_page));
1643         } else
1644                 printk(KERN_INFO "md: no rdev superblock!\n");
1645 }
1646
1647 static void md_print_devices(void)
1648 {
1649         struct list_head *tmp, *tmp2;
1650         mdk_rdev_t *rdev;
1651         mddev_t *mddev;
1652         char b[BDEVNAME_SIZE];
1653
1654         printk("\n");
1655         printk("md:     **********************************\n");
1656         printk("md:     * <COMPLETE RAID STATE PRINTOUT> *\n");
1657         printk("md:     **********************************\n");
1658         for_each_mddev(mddev, tmp) {
1659
1660                 if (mddev->bitmap)
1661                         bitmap_print_sb(mddev->bitmap);
1662                 else
1663                         printk("%s: ", mdname(mddev));
1664                 rdev_for_each(rdev, tmp2, mddev)
1665                         printk("<%s>", bdevname(rdev->bdev,b));
1666                 printk("\n");
1667
1668                 rdev_for_each(rdev, tmp2, mddev)
1669                         print_rdev(rdev);
1670         }
1671         printk("md:     **********************************\n");
1672         printk("\n");
1673 }
1674
1675
1676 static void sync_sbs(mddev_t * mddev, int nospares)
1677 {
1678         /* Update each superblock (in-memory image), but
1679          * if we are allowed to, skip spares which already
1680          * have the right event counter, or have one earlier
1681          * (which would mean they aren't being marked as dirty
1682          * with the rest of the array)
1683          */
1684         mdk_rdev_t *rdev;
1685         struct list_head *tmp;
1686
1687         rdev_for_each(rdev, tmp, mddev) {
1688                 if (rdev->sb_events == mddev->events ||
1689                     (nospares &&
1690                      rdev->raid_disk < 0 &&
1691                      (rdev->sb_events&1)==0 &&
1692                      rdev->sb_events+1 == mddev->events)) {
1693                         /* Don't update this superblock */
1694                         rdev->sb_loaded = 2;
1695                 } else {
1696                         super_types[mddev->major_version].
1697                                 sync_super(mddev, rdev);
1698                         rdev->sb_loaded = 1;
1699                 }
1700         }
1701 }
1702
1703 static void md_update_sb(mddev_t * mddev, int force_change)
1704 {
1705         struct list_head *tmp;
1706         mdk_rdev_t *rdev;
1707         int sync_req;
1708         int nospares = 0;
1709
1710         if (mddev->external)
1711                 return;
1712 repeat:
1713         spin_lock_irq(&mddev->write_lock);
1714
1715         set_bit(MD_CHANGE_PENDING, &mddev->flags);
1716         if (test_and_clear_bit(MD_CHANGE_DEVS, &mddev->flags))
1717                 force_change = 1;
1718         if (test_and_clear_bit(MD_CHANGE_CLEAN, &mddev->flags))
1719                 /* just a clean<-> dirty transition, possibly leave spares alone,
1720                  * though if events isn't the right even/odd, we will have to do
1721                  * spares after all
1722                  */
1723                 nospares = 1;
1724         if (force_change)
1725                 nospares = 0;
1726         if (mddev->degraded)
1727                 /* If the array is degraded, then skipping spares is both
1728                  * dangerous and fairly pointless.
1729                  * Dangerous because a device that was removed from the array
1730                  * might have a event_count that still looks up-to-date,
1731                  * so it can be re-added without a resync.
1732                  * Pointless because if there are any spares to skip,
1733                  * then a recovery will happen and soon that array won't
1734                  * be degraded any more and the spare can go back to sleep then.
1735                  */
1736                 nospares = 0;
1737
1738         sync_req = mddev->in_sync;
1739         mddev->utime = get_seconds();
1740
1741         /* If this is just a dirty<->clean transition, and the array is clean
1742          * and 'events' is odd, we can roll back to the previous clean state */
1743         if (nospares
1744             && (mddev->in_sync && mddev->recovery_cp == MaxSector)
1745             && (mddev->events & 1)
1746             && mddev->events != 1)
1747                 mddev->events--;
1748         else {
1749                 /* otherwise we have to go forward and ... */
1750                 mddev->events ++;
1751                 if (!mddev->in_sync || mddev->recovery_cp != MaxSector) { /* not clean */
1752                         /* .. if the array isn't clean, insist on an odd 'events' */
1753                         if ((mddev->events&1)==0) {
1754                                 mddev->events++;
1755                                 nospares = 0;
1756                         }
1757                 } else {
1758                         /* otherwise insist on an even 'events' (for clean states) */
1759                         if ((mddev->events&1)) {
1760                                 mddev->events++;
1761                                 nospares = 0;
1762                         }
1763                 }
1764         }
1765
1766         if (!mddev->events) {
1767                 /*
1768                  * oops, this 64-bit counter should never wrap.
1769                  * Either we are in around ~1 trillion A.C., assuming
1770                  * 1 reboot per second, or we have a bug:
1771                  */
1772                 MD_BUG();
1773                 mddev->events --;
1774         }
1775
1776         /*
1777          * do not write anything to disk if using
1778          * nonpersistent superblocks
1779          */
1780         if (!mddev->persistent) {
1781                 if (!mddev->external)
1782                         clear_bit(MD_CHANGE_PENDING, &mddev->flags);
1783
1784                 spin_unlock_irq(&mddev->write_lock);
1785                 wake_up(&mddev->sb_wait);
1786                 return;
1787         }
1788         sync_sbs(mddev, nospares);
1789         spin_unlock_irq(&mddev->write_lock);
1790
1791         dprintk(KERN_INFO
1792                 "md: updating %s RAID superblock on device (in sync %d)\n",
1793                 mdname(mddev),mddev->in_sync);
1794
1795         bitmap_update_sb(mddev->bitmap);
1796         rdev_for_each(rdev, tmp, mddev) {
1797                 char b[BDEVNAME_SIZE];
1798                 dprintk(KERN_INFO "md: ");
1799                 if (rdev->sb_loaded != 1)
1800                         continue; /* no noise on spare devices */
1801                 if (test_bit(Faulty, &rdev->flags))
1802                         dprintk("(skipping faulty ");
1803
1804                 dprintk("%s ", bdevname(rdev->bdev,b));
1805                 if (!test_bit(Faulty, &rdev->flags)) {
1806                         md_super_write(mddev,rdev,
1807                                        rdev->sb_start, rdev->sb_size,
1808                                        rdev->sb_page);
1809                         dprintk(KERN_INFO "(write) %s's sb offset: %llu\n",
1810                                 bdevname(rdev->bdev,b),
1811                                 (unsigned long long)rdev->sb_start);
1812                         rdev->sb_events = mddev->events;
1813
1814                 } else
1815                         dprintk(")\n");
1816                 if (mddev->level == LEVEL_MULTIPATH)
1817                         /* only need to write one superblock... */
1818                         break;
1819         }
1820         md_super_wait(mddev);
1821         /* if there was a failure, MD_CHANGE_DEVS was set, and we re-write super */
1822
1823         spin_lock_irq(&mddev->write_lock);
1824         if (mddev->in_sync != sync_req ||
1825             test_bit(MD_CHANGE_DEVS, &mddev->flags)) {
1826                 /* have to write it out again */
1827                 spin_unlock_irq(&mddev->write_lock);
1828                 goto repeat;
1829         }
1830         clear_bit(MD_CHANGE_PENDING, &mddev->flags);
1831         spin_unlock_irq(&mddev->write_lock);
1832         wake_up(&mddev->sb_wait);
1833
1834 }
1835
1836 /* words written to sysfs files may, or may not, be \n terminated.
1837  * We want to accept with case. For this we use cmd_match.
1838  */
1839 static int cmd_match(const char *cmd, const char *str)
1840 {
1841         /* See if cmd, written into a sysfs file, matches
1842          * str.  They must either be the same, or cmd can
1843          * have a trailing newline
1844          */
1845         while (*cmd && *str && *cmd == *str) {
1846                 cmd++;
1847                 str++;
1848         }
1849         if (*cmd == '\n')
1850                 cmd++;
1851         if (*str || *cmd)
1852                 return 0;
1853         return 1;
1854 }
1855
1856 struct rdev_sysfs_entry {
1857         struct attribute attr;
1858         ssize_t (*show)(mdk_rdev_t *, char *);
1859         ssize_t (*store)(mdk_rdev_t *, const char *, size_t);
1860 };
1861
1862 static ssize_t
1863 state_show(mdk_rdev_t *rdev, char *page)
1864 {
1865         char *sep = "";
1866         size_t len = 0;
1867
1868         if (test_bit(Faulty, &rdev->flags)) {
1869                 len+= sprintf(page+len, "%sfaulty",sep);
1870                 sep = ",";
1871         }
1872         if (test_bit(In_sync, &rdev->flags)) {
1873                 len += sprintf(page+len, "%sin_sync",sep);
1874                 sep = ",";
1875         }
1876         if (test_bit(WriteMostly, &rdev->flags)) {
1877                 len += sprintf(page+len, "%swrite_mostly",sep);
1878                 sep = ",";
1879         }
1880         if (test_bit(Blocked, &rdev->flags)) {
1881                 len += sprintf(page+len, "%sblocked", sep);
1882                 sep = ",";
1883         }
1884         if (!test_bit(Faulty, &rdev->flags) &&
1885             !test_bit(In_sync, &rdev->flags)) {
1886                 len += sprintf(page+len, "%sspare", sep);
1887                 sep = ",";
1888         }
1889         return len+sprintf(page+len, "\n");
1890 }
1891
1892 static ssize_t
1893 state_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1894 {
1895         /* can write
1896          *  faulty  - simulates and error
1897          *  remove  - disconnects the device
1898          *  writemostly - sets write_mostly
1899          *  -writemostly - clears write_mostly
1900          *  blocked - sets the Blocked flag
1901          *  -blocked - clears the Blocked flag
1902          */
1903         int err = -EINVAL;
1904         if (cmd_match(buf, "faulty") && rdev->mddev->pers) {
1905                 md_error(rdev->mddev, rdev);
1906                 err = 0;
1907         } else if (cmd_match(buf, "remove")) {
1908                 if (rdev->raid_disk >= 0)
1909                         err = -EBUSY;
1910                 else {
1911                         mddev_t *mddev = rdev->mddev;
1912                         kick_rdev_from_array(rdev);
1913                         if (mddev->pers)
1914                                 md_update_sb(mddev, 1);
1915                         md_new_event(mddev);
1916                         err = 0;
1917                 }
1918         } else if (cmd_match(buf, "writemostly")) {
1919                 set_bit(WriteMostly, &rdev->flags);
1920                 err = 0;
1921         } else if (cmd_match(buf, "-writemostly")) {
1922                 clear_bit(WriteMostly, &rdev->flags);
1923                 err = 0;
1924         } else if (cmd_match(buf, "blocked")) {
1925                 set_bit(Blocked, &rdev->flags);
1926                 err = 0;
1927         } else if (cmd_match(buf, "-blocked")) {
1928                 clear_bit(Blocked, &rdev->flags);
1929                 wake_up(&rdev->blocked_wait);
1930                 set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
1931                 md_wakeup_thread(rdev->mddev->thread);
1932
1933                 err = 0;
1934         }
1935         if (!err)
1936                 sysfs_notify(&rdev->kobj, NULL, "state");
1937         return err ? err : len;
1938 }
1939 static struct rdev_sysfs_entry rdev_state =
1940 __ATTR(state, S_IRUGO|S_IWUSR, state_show, state_store);
1941
1942 static ssize_t
1943 errors_show(mdk_rdev_t *rdev, char *page)
1944 {
1945         return sprintf(page, "%d\n", atomic_read(&rdev->corrected_errors));
1946 }
1947
1948 static ssize_t
1949 errors_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1950 {
1951         char *e;
1952         unsigned long n = simple_strtoul(buf, &e, 10);
1953         if (*buf && (*e == 0 || *e == '\n')) {
1954                 atomic_set(&rdev->corrected_errors, n);
1955                 return len;
1956         }
1957         return -EINVAL;
1958 }
1959 static struct rdev_sysfs_entry rdev_errors =
1960 __ATTR(errors, S_IRUGO|S_IWUSR, errors_show, errors_store);
1961
1962 static ssize_t
1963 slot_show(mdk_rdev_t *rdev, char *page)
1964 {
1965         if (rdev->raid_disk < 0)
1966                 return sprintf(page, "none\n");
1967         else
1968                 return sprintf(page, "%d\n", rdev->raid_disk);
1969 }
1970
1971 static ssize_t
1972 slot_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1973 {
1974         char *e;
1975         int err;
1976         char nm[20];
1977         int slot = simple_strtoul(buf, &e, 10);
1978         if (strncmp(buf, "none", 4)==0)
1979                 slot = -1;
1980         else if (e==buf || (*e && *e!= '\n'))
1981                 return -EINVAL;
1982         if (rdev->mddev->pers && slot == -1) {
1983                 /* Setting 'slot' on an active array requires also
1984                  * updating the 'rd%d' link, and communicating
1985                  * with the personality with ->hot_*_disk.
1986                  * For now we only support removing
1987                  * failed/spare devices.  This normally happens automatically,
1988                  * but not when the metadata is externally managed.
1989                  */
1990                 if (rdev->raid_disk == -1)
1991                         return -EEXIST;
1992                 /* personality does all needed checks */
1993                 if (rdev->mddev->pers->hot_add_disk == NULL)
1994                         return -EINVAL;
1995                 err = rdev->mddev->pers->
1996                         hot_remove_disk(rdev->mddev, rdev->raid_disk);
1997                 if (err)
1998                         return err;
1999                 sprintf(nm, "rd%d", rdev->raid_disk);
2000                 sysfs_remove_link(&rdev->mddev->kobj, nm);
2001                 set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
2002                 md_wakeup_thread(rdev->mddev->thread);
2003         } else if (rdev->mddev->pers) {
2004                 mdk_rdev_t *rdev2;
2005                 struct list_head *tmp;
2006                 /* Activating a spare .. or possibly reactivating
2007                  * if we every get bitmaps working here.
2008                  */
2009
2010                 if (rdev->raid_disk != -1)
2011                         return -EBUSY;
2012
2013                 if (rdev->mddev->pers->hot_add_disk == NULL)
2014                         return -EINVAL;
2015
2016                 rdev_for_each(rdev2, tmp, rdev->mddev)
2017                         if (rdev2->raid_disk == slot)
2018                                 return -EEXIST;
2019
2020                 rdev->raid_disk = slot;
2021                 if (test_bit(In_sync, &rdev->flags))
2022                         rdev->saved_raid_disk = slot;
2023                 else
2024                         rdev->saved_raid_disk = -1;
2025                 err = rdev->mddev->pers->
2026                         hot_add_disk(rdev->mddev, rdev);
2027                 if (err) {
2028                         rdev->raid_disk = -1;
2029                         return err;
2030                 } else
2031                         sysfs_notify(&rdev->kobj, NULL, "state");
2032                 sprintf(nm, "rd%d", rdev->raid_disk);
2033                 if (sysfs_create_link(&rdev->mddev->kobj, &rdev->kobj, nm))
2034                         printk(KERN_WARNING
2035                                "md: cannot register "
2036                                "%s for %s\n",
2037                                nm, mdname(rdev->mddev));
2038
2039                 /* don't wakeup anyone, leave that to userspace. */
2040         } else {
2041                 if (slot >= rdev->mddev->raid_disks)
2042                         return -ENOSPC;
2043                 rdev->raid_disk = slot;
2044                 /* assume it is working */
2045                 clear_bit(Faulty, &rdev->flags);
2046                 clear_bit(WriteMostly, &rdev->flags);
2047                 set_bit(In_sync, &rdev->flags);
2048                 sysfs_notify(&rdev->kobj, NULL, "state");
2049         }
2050         return len;
2051 }
2052
2053
2054 static struct rdev_sysfs_entry rdev_slot =
2055 __ATTR(slot, S_IRUGO|S_IWUSR, slot_show, slot_store);
2056
2057 static ssize_t
2058 offset_show(mdk_rdev_t *rdev, char *page)
2059 {
2060         return sprintf(page, "%llu\n", (unsigned long long)rdev->data_offset);
2061 }
2062
2063 static ssize_t
2064 offset_store(mdk_rdev_t *rdev, const char *buf, size_t len)
2065 {
2066         char *e;
2067         unsigned long long offset = simple_strtoull(buf, &e, 10);
2068         if (e==buf || (*e && *e != '\n'))
2069                 return -EINVAL;
2070         if (rdev->mddev->pers && rdev->raid_disk >= 0)
2071                 return -EBUSY;
2072         if (rdev->size && rdev->mddev->external)
2073                 /* Must set offset before size, so overlap checks
2074                  * can be sane */
2075                 return -EBUSY;
2076         rdev->data_offset = offset;
2077         return len;
2078 }
2079
2080 static struct rdev_sysfs_entry rdev_offset =
2081 __ATTR(offset, S_IRUGO|S_IWUSR, offset_show, offset_store);
2082
2083 static ssize_t
2084 rdev_size_show(mdk_rdev_t *rdev, char *page)
2085 {
2086         return sprintf(page, "%llu\n", (unsigned long long)rdev->size);
2087 }
2088
2089 static int overlaps(sector_t s1, sector_t l1, sector_t s2, sector_t l2)
2090 {
2091         /* check if two start/length pairs overlap */
2092         if (s1+l1 <= s2)
2093                 return 0;
2094         if (s2+l2 <= s1)
2095                 return 0;
2096         return 1;
2097 }
2098
2099 static ssize_t
2100 rdev_size_store(mdk_rdev_t *rdev, const char *buf, size_t len)
2101 {
2102         unsigned long long size;
2103         unsigned long long oldsize = rdev->size;
2104         mddev_t *my_mddev = rdev->mddev;
2105
2106         if (strict_strtoull(buf, 10, &size) < 0)
2107                 return -EINVAL;
2108         if (size < my_mddev->size)
2109                 return -EINVAL;
2110         if (my_mddev->pers && rdev->raid_disk >= 0) {
2111                 if (my_mddev->persistent) {
2112                         size = super_types[my_mddev->major_version].
2113                                 rdev_size_change(rdev, size * 2);
2114                         if (!size)
2115                                 return -EBUSY;
2116                 } else if (!size) {
2117                         size = (rdev->bdev->bd_inode->i_size >> 10);
2118                         size -= rdev->data_offset/2;
2119                 }
2120                 if (size < my_mddev->size)
2121                         return -EINVAL; /* component must fit device */
2122         }
2123
2124         rdev->size = size;
2125         if (size > oldsize && my_mddev->external) {
2126                 /* need to check that all other rdevs with the same ->bdev
2127                  * do not overlap.  We need to unlock the mddev to avoid
2128                  * a deadlock.  We have already changed rdev->size, and if
2129                  * we have to change it back, we will have the lock again.
2130                  */
2131                 mddev_t *mddev;
2132                 int overlap = 0;
2133                 struct list_head *tmp, *tmp2;
2134
2135                 mddev_unlock(my_mddev);
2136                 for_each_mddev(mddev, tmp) {
2137                         mdk_rdev_t *rdev2;
2138
2139                         mddev_lock(mddev);
2140                         rdev_for_each(rdev2, tmp2, mddev)
2141                                 if (test_bit(AllReserved, &rdev2->flags) ||
2142                                     (rdev->bdev == rdev2->bdev &&
2143                                      rdev != rdev2 &&
2144                                      overlaps(rdev->data_offset, rdev->size * 2,
2145                                               rdev2->data_offset,
2146                                               rdev2->size * 2))) {
2147                                         overlap = 1;
2148                                         break;
2149                                 }
2150                         mddev_unlock(mddev);
2151                         if (overlap) {
2152                                 mddev_put(mddev);
2153                                 break;
2154                         }
2155                 }
2156                 mddev_lock(my_mddev);
2157                 if (overlap) {
2158                         /* Someone else could have slipped in a size
2159                          * change here, but doing so is just silly.
2160                          * We put oldsize back because we *know* it is
2161                          * safe, and trust userspace not to race with
2162                          * itself
2163                          */
2164                         rdev->size = oldsize;
2165                         return -EBUSY;
2166                 }
2167         }
2168         return len;
2169 }
2170
2171 static struct rdev_sysfs_entry rdev_size =
2172 __ATTR(size, S_IRUGO|S_IWUSR, rdev_size_show, rdev_size_store);
2173
2174 static struct attribute *rdev_default_attrs[] = {
2175         &rdev_state.attr,
2176         &rdev_errors.attr,
2177         &rdev_slot.attr,
2178         &rdev_offset.attr,
2179         &rdev_size.attr,
2180         NULL,
2181 };
2182 static ssize_t
2183 rdev_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
2184 {
2185         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
2186         mdk_rdev_t *rdev = container_of(kobj, mdk_rdev_t, kobj);
2187         mddev_t *mddev = rdev->mddev;
2188         ssize_t rv;
2189
2190         if (!entry->show)
2191                 return -EIO;
2192
2193         rv = mddev ? mddev_lock(mddev) : -EBUSY;
2194         if (!rv) {
2195                 if (rdev->mddev == NULL)
2196                         rv = -EBUSY;
2197                 else
2198                         rv = entry->show(rdev, page);
2199                 mddev_unlock(mddev);
2200         }
2201         return rv;
2202 }
2203
2204 static ssize_t
2205 rdev_attr_store(struct kobject *kobj, struct attribute *attr,
2206               const char *page, size_t length)
2207 {
2208         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
2209         mdk_rdev_t *rdev = container_of(kobj, mdk_rdev_t, kobj);
2210         ssize_t rv;
2211         mddev_t *mddev = rdev->mddev;
2212
2213         if (!entry->store)
2214                 return -EIO;
2215         if (!capable(CAP_SYS_ADMIN))
2216                 return -EACCES;
2217         rv = mddev ? mddev_lock(mddev): -EBUSY;
2218         if (!rv) {
2219                 if (rdev->mddev == NULL)
2220                         rv = -EBUSY;
2221                 else
2222                         rv = entry->store(rdev, page, length);
2223                 mddev_unlock(mddev);
2224         }
2225         return rv;
2226 }
2227
2228 static void rdev_free(struct kobject *ko)
2229 {
2230         mdk_rdev_t *rdev = container_of(ko, mdk_rdev_t, kobj);
2231         kfree(rdev);
2232 }
2233 static struct sysfs_ops rdev_sysfs_ops = {
2234         .show           = rdev_attr_show,
2235         .store          = rdev_attr_store,
2236 };
2237 static struct kobj_type rdev_ktype = {
2238         .release        = rdev_free,
2239         .sysfs_ops      = &rdev_sysfs_ops,
2240         .default_attrs  = rdev_default_attrs,
2241 };
2242
2243 /*
2244  * Import a device. If 'super_format' >= 0, then sanity check the superblock
2245  *
2246  * mark the device faulty if:
2247  *
2248  *   - the device is nonexistent (zero size)
2249  *   - the device has no valid superblock
2250  *
2251  * a faulty rdev _never_ has rdev->sb set.
2252  */
2253 static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_minor)
2254 {
2255         char b[BDEVNAME_SIZE];
2256         int err;
2257         mdk_rdev_t *rdev;
2258         sector_t size;
2259
2260         rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
2261         if (!rdev) {
2262                 printk(KERN_ERR "md: could not alloc mem for new device!\n");
2263                 return ERR_PTR(-ENOMEM);
2264         }
2265
2266         if ((err = alloc_disk_sb(rdev)))
2267                 goto abort_free;
2268
2269         err = lock_rdev(rdev, newdev, super_format == -2);
2270         if (err)
2271                 goto abort_free;
2272
2273         kobject_init(&rdev->kobj, &rdev_ktype);
2274
2275         rdev->desc_nr = -1;
2276         rdev->saved_raid_disk = -1;
2277         rdev->raid_disk = -1;
2278         rdev->flags = 0;
2279         rdev->data_offset = 0;
2280         rdev->sb_events = 0;
2281         atomic_set(&rdev->nr_pending, 0);
2282         atomic_set(&rdev->read_errors, 0);
2283         atomic_set(&rdev->corrected_errors, 0);
2284
2285         size = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
2286         if (!size) {
2287                 printk(KERN_WARNING
2288                         "md: %s has zero or unknown size, marking faulty!\n",
2289                         bdevname(rdev->bdev,b));
2290                 err = -EINVAL;
2291                 goto abort_free;
2292         }
2293
2294         if (super_format >= 0) {
2295                 err = super_types[super_format].
2296                         load_super(rdev, NULL, super_minor);
2297                 if (err == -EINVAL) {
2298                         printk(KERN_WARNING
2299                                 "md: %s does not have a valid v%d.%d "
2300                                "superblock, not importing!\n",
2301                                 bdevname(rdev->bdev,b),
2302                                super_format, super_minor);
2303                         goto abort_free;
2304                 }
2305                 if (err < 0) {
2306                         printk(KERN_WARNING
2307                                 "md: could not read %s's sb, not importing!\n",
2308                                 bdevname(rdev->bdev,b));
2309                         goto abort_free;
2310                 }
2311         }
2312
2313         INIT_LIST_HEAD(&rdev->same_set);
2314         init_waitqueue_head(&rdev->blocked_wait);
2315
2316         return rdev;
2317
2318 abort_free:
2319         if (rdev->sb_page) {
2320                 if (rdev->bdev)
2321                         unlock_rdev(rdev);
2322                 free_disk_sb(rdev);
2323         }
2324         kfree(rdev);
2325         return ERR_PTR(err);
2326 }
2327
2328 /*
2329  * Check a full RAID array for plausibility
2330  */
2331
2332
2333 static void analyze_sbs(mddev_t * mddev)
2334 {
2335         int i;
2336         struct list_head *tmp;
2337         mdk_rdev_t *rdev, *freshest;
2338         char b[BDEVNAME_SIZE];
2339
2340         freshest = NULL;
2341         rdev_for_each(rdev, tmp, mddev)
2342                 switch (super_types[mddev->major_version].
2343                         load_super(rdev, freshest, mddev->minor_version)) {
2344                 case 1:
2345                         freshest = rdev;
2346                         break;
2347                 case 0:
2348                         break;
2349                 default:
2350                         printk( KERN_ERR \
2351                                 "md: fatal superblock inconsistency in %s"
2352                                 " -- removing from array\n",
2353                                 bdevname(rdev->bdev,b));
2354                         kick_rdev_from_array(rdev);
2355                 }
2356
2357
2358         super_types[mddev->major_version].
2359                 validate_super(mddev, freshest);
2360
2361         i = 0;
2362         rdev_for_each(rdev, tmp, mddev) {
2363                 if (rdev != freshest)
2364                         if (super_types[mddev->major_version].
2365                             validate_super(mddev, rdev)) {
2366                                 printk(KERN_WARNING "md: kicking non-fresh %s"
2367                                         " from array!\n",
2368                                         bdevname(rdev->bdev,b));
2369                                 kick_rdev_from_array(rdev);
2370                                 continue;
2371                         }
2372                 if (mddev->level == LEVEL_MULTIPATH) {
2373                         rdev->desc_nr = i++;
2374                         rdev->raid_disk = rdev->desc_nr;
2375                         set_bit(In_sync, &rdev->flags);
2376                 } else if (rdev->raid_disk >= mddev->raid_disks) {
2377                         rdev->raid_disk = -1;
2378                         clear_bit(In_sync, &rdev->flags);
2379                 }
2380         }
2381
2382
2383
2384         if (mddev->recovery_cp != MaxSector &&
2385             mddev->level >= 1)
2386                 printk(KERN_ERR "md: %s: raid array is not clean"
2387                        " -- starting background reconstruction\n",
2388                        mdname(mddev));
2389
2390 }
2391
2392 static ssize_t
2393 safe_delay_show(mddev_t *mddev, char *page)
2394 {
2395         int msec = (mddev->safemode_delay*1000)/HZ;
2396         return sprintf(page, "%d.%03d\n", msec/1000, msec%1000);
2397 }
2398 static ssize_t
2399 safe_delay_store(mddev_t *mddev, const char *cbuf, size_t len)
2400 {
2401         int scale=1;
2402         int dot=0;
2403         int i;
2404         unsigned long msec;
2405         char buf[30];
2406         char *e;
2407         /* remove a period, and count digits after it */
2408         if (len >= sizeof(buf))
2409                 return -EINVAL;
2410         strlcpy(buf, cbuf, len);
2411         buf[len] = 0;
2412         for (i=0; i<len; i++) {
2413                 if (dot) {
2414                         if (isdigit(buf[i])) {
2415                                 buf[i-1] = buf[i];
2416                                 scale *= 10;
2417                         }
2418                         buf[i] = 0;
2419                 } else if (buf[i] == '.') {
2420                         dot=1;
2421                         buf[i] = 0;
2422                 }
2423         }
2424         msec = simple_strtoul(buf, &e, 10);
2425         if (e == buf || (*e && *e != '\n'))
2426                 return -EINVAL;
2427         msec = (msec * 1000) / scale;
2428         if (msec == 0)
2429                 mddev->safemode_delay = 0;
2430         else {
2431                 mddev->safemode_delay = (msec*HZ)/1000;
2432                 if (mddev->safemode_delay == 0)
2433                         mddev->safemode_delay = 1;
2434         }
2435         return len;
2436 }
2437 static struct md_sysfs_entry md_safe_delay =
2438 __ATTR(safe_mode_delay, S_IRUGO|S_IWUSR,safe_delay_show, safe_delay_store);
2439
2440 static ssize_t
2441 level_show(mddev_t *mddev, char *page)
2442 {
2443         struct mdk_personality *p = mddev->pers;
2444         if (p)
2445                 return sprintf(page, "%s\n", p->name);
2446         else if (mddev->clevel[0])
2447                 return sprintf(page, "%s\n", mddev->clevel);
2448         else if (mddev->level != LEVEL_NONE)
2449                 return sprintf(page, "%d\n", mddev->level);
2450         else
2451                 return 0;
2452 }
2453
2454 static ssize_t
2455 level_store(mddev_t *mddev, const char *buf, size_t len)
2456 {
2457         ssize_t rv = len;
2458         if (mddev->pers)
2459                 return -EBUSY;
2460         if (len == 0)
2461                 return 0;
2462         if (len >= sizeof(mddev->clevel))
2463                 return -ENOSPC;
2464         strncpy(mddev->clevel, buf, len);
2465         if (mddev->clevel[len-1] == '\n')
2466                 len--;
2467         mddev->clevel[len] = 0;
2468         mddev->level = LEVEL_NONE;
2469         return rv;
2470 }
2471
2472 static struct md_sysfs_entry md_level =
2473 __ATTR(level, S_IRUGO|S_IWUSR, level_show, level_store);
2474
2475
2476 static ssize_t
2477 layout_show(mddev_t *mddev, char *page)
2478 {
2479         /* just a number, not meaningful for all levels */
2480         if (mddev->reshape_position != MaxSector &&
2481             mddev->layout != mddev->new_layout)
2482                 return sprintf(page, "%d (%d)\n",
2483                                mddev->new_layout, mddev->layout);
2484         return sprintf(page, "%d\n", mddev->layout);
2485 }
2486
2487 static ssize_t
2488 layout_store(mddev_t *mddev, const char *buf, size_t len)
2489 {
2490         char *e;
2491         unsigned long n = simple_strtoul(buf, &e, 10);
2492
2493         if (!*buf || (*e && *e != '\n'))
2494                 return -EINVAL;
2495
2496         if (mddev->pers)
2497                 return -EBUSY;
2498         if (mddev->reshape_position != MaxSector)
2499                 mddev->new_layout = n;
2500         else
2501                 mddev->layout = n;
2502         return len;
2503 }
2504 static struct md_sysfs_entry md_layout =
2505 __ATTR(layout, S_IRUGO|S_IWUSR, layout_show, layout_store);
2506
2507
2508 static ssize_t
2509 raid_disks_show(mddev_t *mddev, char *page)
2510 {
2511         if (mddev->raid_disks == 0)
2512                 return 0;
2513         if (mddev->reshape_position != MaxSector &&
2514             mddev->delta_disks != 0)
2515                 return sprintf(page, "%d (%d)\n", mddev->raid_disks,
2516                                mddev->raid_disks - mddev->delta_disks);
2517         return sprintf(page, "%d\n", mddev->raid_disks);
2518 }
2519
2520 static int update_raid_disks(mddev_t *mddev, int raid_disks);
2521
2522 static ssize_t
2523 raid_disks_store(mddev_t *mddev, const char *buf, size_t len)
2524 {
2525         char *e;
2526         int rv = 0;
2527         unsigned long n = simple_strtoul(buf, &e, 10);
2528
2529         if (!*buf || (*e && *e != '\n'))
2530                 return -EINVAL;
2531
2532         if (mddev->pers)
2533                 rv = update_raid_disks(mddev, n);
2534         else if (mddev->reshape_position != MaxSector) {
2535                 int olddisks = mddev->raid_disks - mddev->delta_disks;
2536                 mddev->delta_disks = n - olddisks;
2537                 mddev->raid_disks = n;
2538         } else
2539                 mddev->raid_disks = n;
2540         return rv ? rv : len;
2541 }
2542 static struct md_sysfs_entry md_raid_disks =
2543 __ATTR(raid_disks, S_IRUGO|S_IWUSR, raid_disks_show, raid_disks_store);
2544
2545 static ssize_t
2546 chunk_size_show(mddev_t *mddev, char *page)
2547 {
2548         if (mddev->reshape_position != MaxSector &&
2549             mddev->chunk_size != mddev->new_chunk)
2550                 return sprintf(page, "%d (%d)\n", mddev->new_chunk,
2551                                mddev->chunk_size);
2552         return sprintf(page, "%d\n", mddev->chunk_size);
2553 }
2554
2555 static ssize_t
2556 chunk_size_store(mddev_t *mddev, const char *buf, size_t len)
2557 {
2558         /* can only set chunk_size if array is not yet active */
2559         char *e;
2560         unsigned long n = simple_strtoul(buf, &e, 10);
2561
2562         if (!*buf || (*e && *e != '\n'))
2563                 return -EINVAL;
2564
2565         if (mddev->pers)
2566                 return -EBUSY;
2567         else if (mddev->reshape_position != MaxSector)
2568                 mddev->new_chunk = n;
2569         else
2570                 mddev->chunk_size = n;
2571         return len;
2572 }
2573 static struct md_sysfs_entry md_chunk_size =
2574 __ATTR(chunk_size, S_IRUGO|S_IWUSR, chunk_size_show, chunk_size_store);
2575
2576 static ssize_t
2577 resync_start_show(mddev_t *mddev, char *page)
2578 {
2579         return sprintf(page, "%llu\n", (unsigned long long)mddev->recovery_cp);
2580 }
2581
2582 static ssize_t
2583 resync_start_store(mddev_t *mddev, const char *buf, size_t len)
2584 {
2585         char *e;
2586         unsigned long long n = simple_strtoull(buf, &e, 10);
2587
2588         if (mddev->pers)
2589                 return -EBUSY;
2590         if (!*buf || (*e && *e != '\n'))
2591                 return -EINVAL;
2592
2593         mddev->recovery_cp = n;
2594         return len;
2595 }
2596 static struct md_sysfs_entry md_resync_start =
2597 __ATTR(resync_start, S_IRUGO|S_IWUSR, resync_start_show, resync_start_store);
2598
2599 /*
2600  * The array state can be:
2601  *
2602  * clear
2603  *     No devices, no size, no level
2604  *     Equivalent to STOP_ARRAY ioctl
2605  * inactive
2606  *     May have some settings, but array is not active
2607  *        all IO results in error
2608  *     When written, doesn't tear down array, but just stops it
2609  * suspended (not supported yet)
2610  *     All IO requests will block. The array can be reconfigured.
2611  *     Writing this, if accepted, will block until array is quiescent
2612  * readonly
2613  *     no resync can happen.  no superblocks get written.
2614  *     write requests fail
2615  * read-auto
2616  *     like readonly, but behaves like 'clean' on a write request.
2617  *
2618  * clean - no pending writes, but otherwise active.
2619  *     When written to inactive array, starts without resync
2620  *     If a write request arrives then
2621  *       if metadata is known, mark 'dirty' and switch to 'active'.
2622  *       if not known, block and switch to write-pending
2623  *     If written to an active array that has pending writes, then fails.
2624  * active
2625  *     fully active: IO and resync can be happening.
2626  *     When written to inactive array, starts with resync
2627  *
2628  * write-pending
2629  *     clean, but writes are blocked waiting for 'active' to be written.
2630  *
2631  * active-idle
2632  *     like active, but no writes have been seen for a while (100msec).
2633  *
2634  */
2635 enum array_state { clear, inactive, suspended, readonly, read_auto, clean, active,
2636                    write_pending, active_idle, bad_word};
2637 static char *array_states[] = {
2638         "clear", "inactive", "suspended", "readonly", "read-auto", "clean", "active",
2639         "write-pending", "active-idle", NULL };
2640
2641 static int match_word(const char *word, char **list)
2642 {
2643         int n;
2644         for (n=0; list[n]; n++)
2645                 if (cmd_match(word, list[n]))
2646                         break;
2647         return n;
2648 }
2649
2650 static ssize_t
2651 array_state_show(mddev_t *mddev, char *page)
2652 {
2653         enum array_state st = inactive;
2654
2655         if (mddev->pers)
2656                 switch(mddev->ro) {
2657                 case 1:
2658                         st = readonly;
2659                         break;
2660                 case 2:
2661                         st = read_auto;
2662                         break;
2663                 case 0:
2664                         if (mddev->in_sync)
2665                                 st = clean;
2666                         else if (test_bit(MD_CHANGE_CLEAN, &mddev->flags))
2667                                 st = write_pending;
2668                         else if (mddev->safemode)
2669                                 st = active_idle;
2670                         else
2671                                 st = active;
2672                 }
2673         else {
2674                 if (list_empty(&mddev->disks) &&
2675                     mddev->raid_disks == 0 &&
2676                     mddev->size == 0)
2677                         st = clear;
2678                 else
2679                         st = inactive;
2680         }
2681         return sprintf(page, "%s\n", array_states[st]);
2682 }
2683
2684 static int do_md_stop(mddev_t * mddev, int ro, int is_open);
2685 static int do_md_run(mddev_t * mddev);
2686 static int restart_array(mddev_t *mddev);
2687
2688 static ssize_t
2689 array_state_store(mddev_t *mddev, const char *buf, size_t len)
2690 {
2691         int err = -EINVAL;
2692         enum array_state st = match_word(buf, array_states);
2693         switch(st) {
2694         case bad_word:
2695                 break;
2696         case clear:
2697                 /* stopping an active array */
2698                 if (atomic_read(&mddev->active) > 1)
2699                         return -EBUSY;
2700                 err = do_md_stop(mddev, 0, 0);
2701                 break;
2702         case inactive:
2703                 /* stopping an active array */
2704                 if (mddev->pers) {
2705                         if (atomic_read(&mddev->active) > 1)
2706                                 return -EBUSY;
2707                         err = do_md_stop(mddev, 2, 0);
2708                 } else
2709                         err = 0; /* already inactive */
2710                 break;
2711         case suspended:
2712                 break; /* not supported yet */
2713         case readonly:
2714                 if (mddev->pers)
2715                         err = do_md_stop(mddev, 1, 0);
2716                 else {
2717                         mddev->ro = 1;
2718                         set_disk_ro(mddev->gendisk, 1);
2719                         err = do_md_run(mddev);
2720                 }
2721                 break;
2722         case read_auto:
2723                 if (mddev->pers) {
2724                         if (mddev->ro != 1)
2725                                 err = do_md_stop(mddev, 1, 0);
2726                         else
2727                                 err = restart_array(mddev);
2728                         if (err == 0) {
2729                                 mddev->ro = 2;
2730                                 set_disk_ro(mddev->gendisk, 0);
2731                         }
2732                 } else {
2733                         mddev->ro = 2;
2734                         err = do_md_run(mddev);
2735                 }
2736                 break;
2737         case clean:
2738                 if (mddev->pers) {
2739                         restart_array(mddev);
2740                         spin_lock_irq(&mddev->write_lock);
2741                         if (atomic_read(&mddev->writes_pending) == 0) {
2742                                 if (mddev->in_sync == 0) {
2743                                         mddev->in_sync = 1;
2744                                         if (mddev->safemode == 1)
2745                                                 mddev->safemode = 0;
2746                                         if (mddev->persistent)
2747                                                 set_bit(MD_CHANGE_CLEAN,
2748                                                         &mddev->flags);
2749                                 }
2750                                 err = 0;
2751                         } else
2752                                 err = -EBUSY;
2753                         spin_unlock_irq(&mddev->write_lock);
2754                 } else {
2755                         mddev->ro = 0;
2756                         mddev->recovery_cp = MaxSector;
2757                         err = do_md_run(mddev);
2758                 }
2759                 break;
2760         case active:
2761                 if (mddev->pers) {
2762                         restart_array(mddev);
2763                         if (mddev->external)
2764                                 clear_bit(MD_CHANGE_CLEAN, &mddev->flags);
2765                         wake_up(&mddev->sb_wait);
2766                         err = 0;
2767                 } else {
2768                         mddev->ro = 0;
2769                         set_disk_ro(mddev->gendisk, 0);
2770                         err = do_md_run(mddev);
2771                 }
2772                 break;
2773         case write_pending:
2774         case active_idle:
2775                 /* these cannot be set */
2776                 break;
2777         }
2778         if (err)
2779                 return err;
2780         else {
2781                 sysfs_notify(&mddev->kobj, NULL, "array_state");
2782                 return len;
2783         }
2784 }
2785 static struct md_sysfs_entry md_array_state =
2786 __ATTR(array_state, S_IRUGO|S_IWUSR, array_state_show, array_state_store);
2787
2788 static ssize_t
2789 null_show(mddev_t *mddev, char *page)
2790 {
2791         return -EINVAL;
2792 }
2793
2794 static ssize_t
2795 new_dev_store(mddev_t *mddev, const char *buf, size_t len)
2796 {
2797         /* buf must be %d:%d\n? giving major and minor numbers */
2798         /* The new device is added to the array.
2799          * If the array has a persistent superblock, we read the
2800          * superblock to initialise info and check validity.
2801          * Otherwise, only checking done is that in bind_rdev_to_array,
2802          * which mainly checks size.
2803          */
2804         char *e;
2805         int major = simple_strtoul(buf, &e, 10);
2806         int minor;
2807         dev_t dev;
2808         mdk_rdev_t *rdev;
2809         int err;
2810
2811         if (!*buf || *e != ':' || !e[1] || e[1] == '\n')
2812                 return -EINVAL;
2813         minor = simple_strtoul(e+1, &e, 10);
2814         if (*e && *e != '\n')
2815                 return -EINVAL;
2816         dev = MKDEV(major, minor);
2817         if (major != MAJOR(dev) ||
2818             minor != MINOR(dev))
2819                 return -EOVERFLOW;
2820
2821
2822         if (mddev->persistent) {
2823                 rdev = md_import_device(dev, mddev->major_version,
2824                                         mddev->minor_version);
2825                 if (!IS_ERR(rdev) && !list_empty(&mddev->disks)) {
2826                         mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
2827                                                        mdk_rdev_t, same_set);
2828                         err = super_types[mddev->major_version]
2829                                 .load_super(rdev, rdev0, mddev->minor_version);
2830                         if (err < 0)
2831                                 goto out;
2832                 }
2833         } else if (mddev->external)
2834                 rdev = md_import_device(dev, -2, -1);
2835         else
2836                 rdev = md_import_device(dev, -1, -1);
2837
2838         if (IS_ERR(rdev))
2839                 return PTR_ERR(rdev);
2840         err = bind_rdev_to_array(rdev, mddev);
2841  out:
2842         if (err)
2843                 export_rdev(rdev);
2844         return err ? err : len;
2845 }
2846
2847 static struct md_sysfs_entry md_new_device =
2848 __ATTR(new_dev, S_IWUSR, null_show, new_dev_store);
2849
2850 static ssize_t
2851 bitmap_store(mddev_t *mddev, const char *buf, size_t len)
2852 {
2853         char *end;
2854         unsigned long chunk, end_chunk;
2855
2856         if (!mddev->bitmap)
2857                 goto out;
2858         /* buf should be <chunk> <chunk> ... or <chunk>-<chunk> ... (range) */
2859         while (*buf) {
2860                 chunk = end_chunk = simple_strtoul(buf, &end, 0);
2861                 if (buf == end) break;
2862                 if (*end == '-') { /* range */
2863                         buf = end + 1;
2864                         end_chunk = simple_strtoul(buf, &end, 0);
2865                         if (buf == end) break;
2866                 }
2867                 if (*end && !isspace(*end)) break;
2868                 bitmap_dirty_bits(mddev->bitmap, chunk, end_chunk);
2869                 buf = end;
2870                 while (isspace(*buf)) buf++;
2871         }
2872         bitmap_unplug(mddev->bitmap); /* flush the bits to disk */
2873 out:
2874         return len;
2875 }
2876
2877 static struct md_sysfs_entry md_bitmap =
2878 __ATTR(bitmap_set_bits, S_IWUSR, null_show, bitmap_store);
2879
2880 static ssize_t
2881 size_show(mddev_t *mddev, char *page)
2882 {
2883         return sprintf(page, "%llu\n", (unsigned long long)mddev->size);
2884 }
2885
2886 static int update_size(mddev_t *mddev, sector_t num_sectors);
2887
2888 static ssize_t
2889 size_store(mddev_t *mddev, const char *buf, size_t len)
2890 {
2891         /* If array is inactive, we can reduce the component size, but
2892          * not increase it (except from 0).
2893          * If array is active, we can try an on-line resize
2894          */
2895         char *e;
2896         int err = 0;
2897         unsigned long long size = simple_strtoull(buf, &e, 10);
2898         if (!*buf || *buf == '\n' ||
2899             (*e && *e != '\n'))
2900                 return -EINVAL;
2901
2902         if (mddev->pers) {
2903                 err = update_size(mddev, size * 2);
2904                 md_update_sb(mddev, 1);
2905         } else {
2906                 if (mddev->size == 0 ||
2907                     mddev->size > size)
2908                         mddev->size = size;
2909                 else
2910                         err = -ENOSPC;
2911         }
2912         return err ? err : len;
2913 }
2914
2915 static struct md_sysfs_entry md_size =
2916 __ATTR(component_size, S_IRUGO|S_IWUSR, size_show, size_store);
2917
2918
2919 /* Metdata version.
2920  * This is one of
2921  *   'none' for arrays with no metadata (good luck...)
2922  *   'external' for arrays with externally managed metadata,
2923  * or N.M for internally known formats
2924  */
2925 static ssize_t
2926 metadata_show(mddev_t *mddev, char *page)
2927 {
2928         if (mddev->persistent)
2929                 return sprintf(page, "%d.%d\n",
2930                                mddev->major_version, mddev->minor_version);
2931         else if (mddev->external)
2932                 return sprintf(page, "external:%s\n", mddev->metadata_type);
2933         else
2934                 return sprintf(page, "none\n");
2935 }
2936
2937 static ssize_t
2938 metadata_store(mddev_t *mddev, const char *buf, size_t len)
2939 {
2940         int major, minor;
2941         char *e;
2942         if (!list_empty(&mddev->disks))
2943                 return -EBUSY;
2944
2945         if (cmd_match(buf, "none")) {
2946                 mddev->persistent = 0;
2947                 mddev->external = 0;
2948                 mddev->major_version = 0;
2949                 mddev->minor_version = 90;
2950                 return len;
2951         }
2952         if (strncmp(buf, "external:", 9) == 0) {
2953                 size_t namelen = len-9;
2954                 if (namelen >= sizeof(mddev->metadata_type))
2955                         namelen = sizeof(mddev->metadata_type)-1;
2956                 strncpy(mddev->metadata_type, buf+9, namelen);
2957                 mddev->metadata_type[namelen] = 0;
2958                 if (namelen && mddev->metadata_type[namelen-1] == '\n')
2959                         mddev->metadata_type[--namelen] = 0;
2960                 mddev->persistent = 0;
2961                 mddev->external = 1;
2962                 mddev->major_version = 0;
2963                 mddev->minor_version = 90;
2964                 return len;
2965         }
2966         major = simple_strtoul(buf, &e, 10);
2967         if (e==buf || *e != '.')
2968                 return -EINVAL;
2969         buf = e+1;
2970         minor = simple_strtoul(buf, &e, 10);
2971         if (e==buf || (*e && *e != '\n') )
2972                 return -EINVAL;
2973         if (major >= ARRAY_SIZE(super_types) || super_types[major].name == NULL)
2974                 return -ENOENT;
2975         mddev->major_version = major;
2976         mddev->minor_version = minor;
2977         mddev->persistent = 1;
2978         mddev->external = 0;
2979         return len;
2980 }
2981
2982 static struct md_sysfs_entry md_metadata =
2983 __ATTR(metadata_version, S_IRUGO|S_IWUSR, metadata_show, metadata_store);
2984
2985 static ssize_t
2986 action_show(mddev_t *mddev, char *page)
2987 {
2988         char *type = "idle";
2989         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
2990             (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) {
2991                 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
2992                         type = "reshape";
2993                 else if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
2994                         if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2995                                 type = "resync";
2996                         else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
2997                                 type = "check";
2998                         else
2999                                 type = "repair";
3000                 } else if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery))
3001                         type = "recover";
3002         }
3003         return sprintf(page, "%s\n", type);
3004 }
3005
3006 static ssize_t
3007 action_store(mddev_t *mddev, const char *page, size_t len)
3008 {
3009         if (!mddev->pers || !mddev->pers->sync_request)
3010                 return -EINVAL;
3011
3012         if (cmd_match(page, "idle")) {
3013                 if (mddev->sync_thread) {
3014                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3015                         md_unregister_thread(mddev->sync_thread);
3016                         mddev->sync_thread = NULL;
3017                         mddev->recovery = 0;
3018                 }
3019         } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
3020                    test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
3021                 return -EBUSY;
3022         else if (cmd_match(page, "resync"))
3023                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3024         else if (cmd_match(page, "recover")) {
3025                 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
3026                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3027         } else if (cmd_match(page, "reshape")) {
3028                 int err;
3029                 if (mddev->pers->start_reshape == NULL)
3030                         return -EINVAL;
3031                 err = mddev->pers->start_reshape(mddev);
3032                 if (err)
3033                         return err;
3034                 sysfs_notify(&mddev->kobj, NULL, "degraded");
3035         } else {
3036                 if (cmd_match(page, "check"))
3037                         set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
3038                 else if (!cmd_match(page, "repair"))
3039                         return -EINVAL;
3040                 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
3041                 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3042         }
3043         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3044         md_wakeup_thread(mddev->thread);
3045         sysfs_notify(&mddev->kobj, NULL, "sync_action");
3046         return len;
3047 }
3048
3049 static ssize_t
3050 mismatch_cnt_show(mddev_t *mddev, char *page)
3051 {
3052         return sprintf(page, "%llu\n",
3053                        (unsigned long long) mddev->resync_mismatches);
3054 }
3055
3056 static struct md_sysfs_entry md_scan_mode =
3057 __ATTR(sync_action, S_IRUGO|S_IWUSR, action_show, action_store);
3058
3059
3060 static struct md_sysfs_entry md_mismatches = __ATTR_RO(mismatch_cnt);
3061
3062 static ssize_t
3063 sync_min_show(mddev_t *mddev, char *page)
3064 {
3065         return sprintf(page, "%d (%s)\n", speed_min(mddev),
3066                        mddev->sync_speed_min ? "local": "system");
3067 }
3068
3069 static ssize_t
3070 sync_min_store(mddev_t *mddev, const char *buf, size_t len)
3071 {
3072         int min;
3073         char *e;
3074         if (strncmp(buf, "system", 6)==0) {
3075                 mddev->sync_speed_min = 0;
3076                 return len;
3077         }
3078         min = simple_strtoul(buf, &e, 10);
3079         if (buf == e || (*e && *e != '\n') || min <= 0)
3080                 return -EINVAL;
3081         mddev->sync_speed_min = min;
3082         return len;
3083 }
3084
3085 static struct md_sysfs_entry md_sync_min =
3086 __ATTR(sync_speed_min, S_IRUGO|S_IWUSR, sync_min_show, sync_min_store);
3087
3088 static ssize_t
3089 sync_max_show(mddev_t *mddev, char *page)
3090 {
3091         return sprintf(page, "%d (%s)\n", speed_max(mddev),
3092                        mddev->sync_speed_max ? "local": "system");
3093 }
3094
3095 static ssize_t
3096 sync_max_store(mddev_t *mddev, const char *buf, size_t len)
3097 {
3098         int max;
3099         char *e;
3100         if (strncmp(buf, "system", 6)==0) {
3101                 mddev->sync_speed_max = 0;
3102                 return len;
3103         }
3104         max = simple_strtoul(buf, &e, 10);
3105         if (buf == e || (*e && *e != '\n') || max <= 0)
3106                 return -EINVAL;
3107         mddev->sync_speed_max = max;
3108         return len;
3109 }
3110
3111 static struct md_sysfs_entry md_sync_max =
3112 __ATTR(sync_speed_max, S_IRUGO|S_IWUSR, sync_max_show, sync_max_store);
3113
3114 static ssize_t
3115 degraded_show(mddev_t *mddev, char *page)
3116 {
3117         return sprintf(page, "%d\n", mddev->degraded);
3118 }
3119 static struct md_sysfs_entry md_degraded = __ATTR_RO(degraded);
3120
3121 static ssize_t
3122 sync_force_parallel_show(mddev_t *mddev, char *page)
3123 {
3124         return sprintf(page, "%d\n", mddev->parallel_resync);
3125 }
3126
3127 static ssize_t
3128 sync_force_parallel_store(mddev_t *mddev, const char *buf, size_t len)
3129 {
3130         long n;
3131
3132         if (strict_strtol(buf, 10, &n))
3133                 return -EINVAL;
3134
3135         if (n != 0 && n != 1)
3136                 return -EINVAL;
3137
3138         mddev->parallel_resync = n;
3139
3140         if (mddev->sync_thread)
3141                 wake_up(&resync_wait);
3142
3143         return len;
3144 }
3145
3146 /* force parallel resync, even with shared block devices */
3147 static struct md_sysfs_entry md_sync_force_parallel =
3148 __ATTR(sync_force_parallel, S_IRUGO|S_IWUSR,
3149        sync_force_parallel_show, sync_force_parallel_store);
3150
3151 static ssize_t
3152 sync_speed_show(mddev_t *mddev, char *page)
3153 {
3154         unsigned long resync, dt, db;
3155         resync = mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active);
3156         dt = (jiffies - mddev->resync_mark) / HZ;
3157         if (!dt) dt++;
3158         db = resync - mddev->resync_mark_cnt;
3159         return sprintf(page, "%lu\n", db/dt/2); /* K/sec */
3160 }
3161
3162 static struct md_sysfs_entry md_sync_speed = __ATTR_RO(sync_speed);
3163
3164 static ssize_t
3165 sync_completed_show(mddev_t *mddev, char *page)
3166 {
3167         unsigned long max_blocks, resync;
3168
3169         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
3170                 max_blocks = mddev->resync_max_sectors;
3171         else
3172                 max_blocks = mddev->size << 1;
3173
3174         resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active));
3175         return sprintf(page, "%lu / %lu\n", resync, max_blocks);
3176 }
3177
3178 static struct md_sysfs_entry md_sync_completed = __ATTR_RO(sync_completed);
3179
3180 static ssize_t
3181 min_sync_show(mddev_t *mddev, char *page)
3182 {
3183         return sprintf(page, "%llu\n",
3184                        (unsigned long long)mddev->resync_min);
3185 }
3186 static ssize_t
3187 min_sync_store(mddev_t *mddev, const char *buf, size_t len)
3188 {
3189         unsigned long long min;
3190         if (strict_strtoull(buf, 10, &min))
3191                 return -EINVAL;
3192         if (min > mddev->resync_max)
3193                 return -EINVAL;
3194         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
3195                 return -EBUSY;
3196
3197         /* Must be a multiple of chunk_size */
3198         if (mddev->chunk_size) {
3199                 if (min & (sector_t)((mddev->chunk_size>>9)-1))
3200                         return -EINVAL;
3201         }
3202         mddev->resync_min = min;
3203
3204         return len;
3205 }
3206
3207 static struct md_sysfs_entry md_min_sync =
3208 __ATTR(sync_min, S_IRUGO|S_IWUSR, min_sync_show, min_sync_store);
3209
3210 static ssize_t
3211 max_sync_show(mddev_t *mddev, char *page)
3212 {
3213         if (mddev->resync_max == MaxSector)
3214                 return sprintf(page, "max\n");
3215         else
3216                 return sprintf(page, "%llu\n",
3217                                (unsigned long long)mddev->resync_max);
3218 }
3219 static ssize_t
3220 max_sync_store(mddev_t *mddev, const char *buf, size_t len)
3221 {
3222         if (strncmp(buf, "max", 3) == 0)
3223                 mddev->resync_max = MaxSector;
3224         else {
3225                 unsigned long long max;
3226                 if (strict_strtoull(buf, 10, &max))
3227                         return -EINVAL;
3228                 if (max < mddev->resync_min)
3229                         return -EINVAL;
3230                 if (max < mddev->resync_max &&
3231                     test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
3232                         return -EBUSY;
3233
3234                 /* Must be a multiple of chunk_size */
3235                 if (mddev->chunk_size) {
3236                         if (max & (sector_t)((mddev->chunk_size>>9)-1))
3237                                 return -EINVAL;
3238                 }
3239                 mddev->resync_max = max;
3240         }
3241         wake_up(&mddev->recovery_wait);
3242         return len;
3243 }
3244
3245 static struct md_sysfs_entry md_max_sync =
3246 __ATTR(sync_max, S_IRUGO|S_IWUSR, max_sync_show, max_sync_store);
3247
3248 static ssize_t
3249 suspend_lo_show(mddev_t *mddev, char *page)
3250 {
3251         return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_lo);
3252 }
3253
3254 static ssize_t
3255 suspend_lo_store(mddev_t *mddev, const char *buf, size_t len)
3256 {
3257         char *e;
3258         unsigned long long new = simple_strtoull(buf, &e, 10);
3259
3260         if (mddev->pers->quiesce == NULL)
3261                 return -EINVAL;
3262         if (buf == e || (*e && *e != '\n'))
3263                 return -EINVAL;
3264         if (new >= mddev->suspend_hi ||
3265             (new > mddev->suspend_lo && new < mddev->suspend_hi)) {
3266                 mddev->suspend_lo = new;
3267                 mddev->pers->quiesce(mddev, 2);
3268                 return len;
3269         } else
3270                 return -EINVAL;
3271 }
3272 static struct md_sysfs_entry md_suspend_lo =
3273 __ATTR(suspend_lo, S_IRUGO|S_IWUSR, suspend_lo_show, suspend_lo_store);
3274
3275
3276 static ssize_t
3277 suspend_hi_show(mddev_t *mddev, char *page)
3278 {
3279         return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_hi);
3280 }
3281
3282 static ssize_t
3283 suspend_hi_store(mddev_t *mddev, const char *buf, size_t len)
3284 {
3285         char *e;
3286         unsigned long long new = simple_strtoull(buf, &e, 10);
3287
3288         if (mddev->pers->quiesce == NULL)
3289                 return -EINVAL;
3290         if (buf == e || (*e && *e != '\n'))
3291                 return -EINVAL;
3292         if ((new <= mddev->suspend_lo && mddev->suspend_lo >= mddev->suspend_hi) ||
3293             (new > mddev->suspend_lo && new > mddev->suspend_hi)) {
3294                 mddev->suspend_hi = new;
3295                 mddev->pers->quiesce(mddev, 1);
3296                 mddev->pers->quiesce(mddev, 0);
3297                 return len;
3298         } else
3299                 return -EINVAL;
3300 }
3301 static struct md_sysfs_entry md_suspend_hi =
3302 __ATTR(suspend_hi, S_IRUGO|S_IWUSR, suspend_hi_show, suspend_hi_store);
3303
3304 static ssize_t
3305 reshape_position_show(mddev_t *mddev, char *page)
3306 {
3307         if (mddev->reshape_position != MaxSector)
3308                 return sprintf(page, "%llu\n",
3309                                (unsigned long long)mddev->reshape_position);
3310         strcpy(page, "none\n");
3311         return 5;
3312 }
3313
3314 static ssize_t
3315 reshape_position_store(mddev_t *mddev, const char *buf, size_t len)
3316 {
3317         char *e;
3318         unsigned long long new = simple_strtoull(buf, &e, 10);
3319         if (mddev->pers)
3320                 return -EBUSY;
3321         if (buf == e || (*e && *e != '\n'))
3322                 return -EINVAL;
3323         mddev->reshape_position = new;
3324         mddev->delta_disks = 0;
3325         mddev->new_level = mddev->level;
3326         mddev->new_layout = mddev->layout;
3327         mddev->new_chunk = mddev->chunk_size;
3328         return len;
3329 }
3330
3331 static struct md_sysfs_entry md_reshape_position =
3332 __ATTR(reshape_position, S_IRUGO|S_IWUSR, reshape_position_show,
3333        reshape_position_store);
3334
3335
3336 static struct attribute *md_default_attrs[] = {
3337         &md_level.attr,
3338         &md_layout.attr,
3339         &md_raid_disks.attr,
3340         &md_chunk_size.attr,
3341         &md_size.attr,
3342         &md_resync_start.attr,
3343         &md_metadata.attr,
3344         &md_new_device.attr,
3345         &md_safe_delay.attr,
3346         &md_array_state.attr,
3347         &md_reshape_position.attr,
3348         NULL,
3349 };
3350
3351 static struct attribute *md_redundancy_attrs[] = {
3352         &md_scan_mode.attr,
3353         &md_mismatches.attr,
3354         &md_sync_min.attr,
3355         &md_sync_max.attr,
3356         &md_sync_speed.attr,
3357         &md_sync_force_parallel.attr,
3358         &md_sync_completed.attr,
3359         &md_min_sync.attr,
3360         &md_max_sync.attr,
3361         &md_suspend_lo.attr,
3362         &md_suspend_hi.attr,
3363         &md_bitmap.attr,
3364         &md_degraded.attr,
3365         NULL,
3366 };
3367 static struct attribute_group md_redundancy_group = {
3368         .name = NULL,
3369         .attrs = md_redundancy_attrs,
3370 };
3371
3372
3373 static ssize_t
3374 md_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
3375 {
3376         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
3377         mddev_t *mddev = container_of(kobj, struct mddev_s, kobj);
3378         ssize_t rv;
3379
3380         if (!entry->show)
3381                 return -EIO;
3382         rv = mddev_lock(mddev);
3383         if (!rv) {
3384                 rv = entry->show(mddev, page);
3385                 mddev_unlock(mddev);
3386         }
3387         return rv;
3388 }
3389
3390 static ssize_t
3391 md_attr_store(struct kobject *kobj, struct attribute *attr,
3392               const char *page, size_t length)
3393 {
3394         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
3395         mddev_t *mddev = container_of(kobj, struct mddev_s, kobj);
3396         ssize_t rv;
3397
3398         if (!entry->store)
3399                 return -EIO;
3400         if (!capable(CAP_SYS_ADMIN))
3401                 return -EACCES;
3402         rv = mddev_lock(mddev);
3403         if (!rv) {
3404                 rv = entry->store(mddev, page, length);
3405                 mddev_unlock(mddev);
3406         }
3407         return rv;
3408 }
3409
3410 static void md_free(struct kobject *ko)
3411 {
3412         mddev_t *mddev = container_of(ko, mddev_t, kobj);
3413         kfree(mddev);
3414 }
3415
3416 static struct sysfs_ops md_sysfs_ops = {
3417         .show   = md_attr_show,
3418         .store  = md_attr_store,
3419 };
3420 static struct kobj_type md_ktype = {
3421         .release        = md_free,
3422         .sysfs_ops      = &md_sysfs_ops,
3423         .default_attrs  = md_default_attrs,
3424 };
3425
3426 int mdp_major = 0;
3427
3428 static struct kobject *md_probe(dev_t dev, int *part, void *data)
3429 {
3430         static DEFINE_MUTEX(disks_mutex);
3431         mddev_t *mddev = mddev_find(dev);
3432         struct gendisk *disk;
3433         int partitioned = (MAJOR(dev) != MD_MAJOR);
3434         int shift = partitioned ? MdpMinorShift : 0;
3435         int unit = MINOR(dev) >> shift;
3436         int error;
3437
3438         if (!mddev)
3439                 return NULL;
3440
3441         mutex_lock(&disks_mutex);
3442         if (mddev->gendisk) {
3443                 mutex_unlock(&disks_mutex);
3444                 mddev_put(mddev);
3445                 return NULL;
3446         }
3447         disk = alloc_disk(1 << shift);
3448         if (!disk) {
3449                 mutex_unlock(&disks_mutex);
3450                 mddev_put(mddev);
3451                 return NULL;
3452         }
3453         disk->major = MAJOR(dev);
3454         disk->first_minor = unit << shift;
3455         if (partitioned)
3456                 sprintf(disk->disk_name, "md_d%d", unit);
3457         else
3458                 sprintf(disk->disk_name, "md%d", unit);
3459         disk->fops = &md_fops;
3460         disk->private_data = mddev;
3461         disk->queue = mddev->queue;
3462         add_disk(disk);
3463         mddev->gendisk = disk;
3464         error = kobject_init_and_add(&mddev->kobj, &md_ktype, &disk->dev.kobj,
3465                                      "%s", "md");
3466         mutex_unlock(&disks_mutex);
3467         if (error)
3468                 printk(KERN_WARNING "md: cannot register %s/md - name in use\n",
3469                        disk->disk_name);
3470         else
3471                 kobject_uevent(&mddev->kobj, KOBJ_ADD);
3472         return NULL;
3473 }
3474
3475 static void md_safemode_timeout(unsigned long data)
3476 {
3477         mddev_t *mddev = (mddev_t *) data;
3478
3479         if (!atomic_read(&mddev->writes_pending)) {
3480                 mddev->safemode = 1;
3481                 if (mddev->external)
3482                         sysfs_notify(&mddev->kobj, NULL, "array_state");
3483         }
3484         md_wakeup_thread(mddev->thread);
3485 }
3486
3487 static int start_dirty_degraded;
3488
3489 static int do_md_run(mddev_t * mddev)
3490 {
3491         int err;
3492         int chunk_size;
3493         struct list_head *tmp;
3494         mdk_rdev_t *rdev;
3495         struct gendisk *disk;
3496         struct mdk_personality *pers;
3497         char b[BDEVNAME_SIZE];
3498
3499         if (list_empty(&mddev->disks))
3500                 /* cannot run an array with no devices.. */
3501                 return -EINVAL;
3502
3503         if (mddev->pers)
3504                 return -EBUSY;
3505
3506         /*
3507          * Analyze all RAID superblock(s)
3508          */
3509         if (!mddev->raid_disks) {
3510                 if (!mddev->persistent)
3511                         return -EINVAL;
3512                 analyze_sbs(mddev);
3513         }
3514
3515         chunk_size = mddev->chunk_size;
3516
3517         if (chunk_size) {
3518                 if (chunk_size > MAX_CHUNK_SIZE) {
3519                         printk(KERN_ERR "too big chunk_size: %d > %d\n",
3520                                 chunk_size, MAX_CHUNK_SIZE);
3521                         return -EINVAL;
3522                 }
3523                 /*
3524                  * chunk-size has to be a power of 2 and multiples of PAGE_SIZE
3525                  */
3526                 if ( (1 << ffz(~chunk_size)) != chunk_size) {
3527                         printk(KERN_ERR "chunk_size of %d not valid\n", chunk_size);
3528                         return -EINVAL;
3529                 }
3530                 if (chunk_size < PAGE_SIZE) {
3531                         printk(KERN_ERR "too small chunk_size: %d < %ld\n",
3532                                 chunk_size, PAGE_SIZE);
3533                         return -EINVAL;
3534                 }
3535
3536                 /* devices must have minimum size of one chunk */
3537                 rdev_for_each(rdev, tmp, mddev) {
3538                         if (test_bit(Faulty, &rdev->flags))
3539                                 continue;
3540                         if (rdev->size < chunk_size / 1024) {
3541                                 printk(KERN_WARNING
3542                                         "md: Dev %s smaller than chunk_size:"
3543                                         " %lluk < %dk\n",
3544                                         bdevname(rdev->bdev,b),
3545                                         (unsigned long long)rdev->size,
3546                                         chunk_size / 1024);
3547                                 return -EINVAL;
3548                         }
3549                 }
3550         }
3551
3552 #ifdef CONFIG_KMOD
3553         if (mddev->level != LEVEL_NONE)
3554                 request_module("md-level-%d", mddev->level);
3555         else if (mddev->clevel[0])
3556                 request_module("md-%s", mddev->clevel);
3557 #endif
3558
3559         /*
3560          * Drop all container device buffers, from now on
3561          * the only valid external interface is through the md
3562          * device.
3563          */
3564         rdev_for_each(rdev, tmp, mddev) {
3565                 if (test_bit(Faulty, &rdev->flags))
3566                         continue;
3567                 sync_blockdev(rdev->bdev);
3568                 invalidate_bdev(rdev->bdev);
3569
3570                 /* perform some consistency tests on the device.
3571                  * We don't want the data to overlap the metadata,
3572                  * Internal Bitmap issues has handled elsewhere.
3573                  */
3574                 if (rdev->data_offset < rdev->sb_start) {
3575                         if (mddev->size &&
3576                             rdev->data_offset + mddev->size*2
3577                             > rdev->sb_start) {
3578                                 printk("md: %s: data overlaps metadata\n",
3579                                        mdname(mddev));
3580                                 return -EINVAL;
3581                         }
3582                 } else {
3583                         if (rdev->sb_start + rdev->sb_size/512
3584                             > rdev->data_offset) {
3585                                 printk("md: %s: metadata overlaps data\n",
3586                                        mdname(mddev));
3587                                 return -EINVAL;
3588                         }
3589                 }
3590                 sysfs_notify(&rdev->kobj, NULL, "state");
3591         }
3592
3593         md_probe(mddev->unit, NULL, NULL);
3594         disk = mddev->gendisk;
3595         if (!disk)
3596                 return -ENOMEM;
3597
3598         spin_lock(&pers_lock);
3599         pers = find_pers(mddev->level, mddev->clevel);
3600         if (!pers || !try_module_get(pers->owner)) {
3601                 spin_unlock(&pers_lock);
3602                 if (mddev->level != LEVEL_NONE)
3603                         printk(KERN_WARNING "md: personality for level %d is not loaded!\n",
3604                                mddev->level);
3605                 else
3606                         printk(KERN_WARNING "md: personality for level %s is not loaded!\n",
3607                                mddev->clevel);
3608                 return -EINVAL;
3609         }
3610         mddev->pers = pers;
3611         spin_unlock(&pers_lock);
3612         mddev->level = pers->level;
3613         strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
3614
3615         if (mddev->reshape_position != MaxSector &&
3616             pers->start_reshape == NULL) {
3617                 /* This personality cannot handle reshaping... */
3618                 mddev->pers = NULL;
3619                 module_put(pers->owner);
3620                 return -EINVAL;
3621         }
3622
3623         if (pers->sync_request) {
3624                 /* Warn if this is a potentially silly
3625                  * configuration.
3626                  */
3627                 char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
3628                 mdk_rdev_t *rdev2;
3629                 struct list_head *tmp2;
3630                 int warned = 0;
3631                 rdev_for_each(rdev, tmp, mddev) {
3632                         rdev_for_each(rdev2, tmp2, mddev) {
3633                                 if (rdev < rdev2 &&
3634                                     rdev->bdev->bd_contains ==
3635                                     rdev2->bdev->bd_contains) {
3636                                         printk(KERN_WARNING
3637                                                "%s: WARNING: %s appears to be"
3638                                                " on the same physical disk as"
3639                                                " %s.\n",
3640                                                mdname(mddev),
3641                                                bdevname(rdev->bdev,b),
3642                                                bdevname(rdev2->bdev,b2));
3643                                         warned = 1;
3644                                 }
3645                         }
3646                 }
3647                 if (warned)
3648                         printk(KERN_WARNING
3649                                "True protection against single-disk"
3650                                " failure might be compromised.\n");
3651         }
3652
3653         mddev->recovery = 0;
3654         mddev->resync_max_sectors = mddev->size << 1; /* may be over-ridden by personality */
3655         mddev->barriers_work = 1;
3656         mddev->ok_start_degraded = start_dirty_degraded;
3657
3658         if (start_readonly)
3659                 mddev->ro = 2; /* read-only, but switch on first write */
3660
3661         err = mddev->pers->run(mddev);
3662         if (err)
3663                 printk(KERN_ERR "md: pers->run() failed ...\n");
3664         else if (mddev->pers->sync_request) {
3665                 err = bitmap_create(mddev);
3666                 if (err) {
3667                         printk(KERN_ERR "%s: failed to create bitmap (%d)\n",
3668                                mdname(mddev), err);
3669                         mddev->pers->stop(mddev);
3670                 }
3671         }
3672         if (err) {
3673                 module_put(mddev->pers->owner);
3674                 mddev->pers = NULL;
3675                 bitmap_destroy(mddev);
3676                 return err;
3677         }
3678         if (mddev->pers->sync_request) {
3679                 if (sysfs_create_group(&mddev->kobj, &md_redundancy_group))
3680                         printk(KERN_WARNING
3681                                "md: cannot register extra attributes for %s\n",
3682                                mdname(mddev));
3683         } else if (mddev->ro == 2) /* auto-readonly not meaningful */
3684                 mddev->ro = 0;
3685
3686         atomic_set(&mddev->writes_pending,0);
3687         mddev->safemode = 0;
3688         mddev->safemode_timer.function = md_safemode_timeout;
3689         mddev->safemode_timer.data = (unsigned long) mddev;
3690         mddev->safemode_delay = (200 * HZ)/1000 +1; /* 200 msec delay */
3691         mddev->in_sync = 1;
3692
3693         rdev_for_each(rdev, tmp, mddev)
3694                 if (rdev->raid_disk >= 0) {
3695                         char nm[20];
3696                         sprintf(nm, "rd%d", rdev->raid_disk);
3697                         if (sysfs_create_link(&mddev->kobj, &rdev->kobj, nm))
3698                                 printk("md: cannot register %s for %s\n",
3699                                        nm, mdname(mddev));
3700                 }
3701
3702         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3703
3704         if (mddev->flags)
3705                 md_update_sb(mddev, 0);
3706
3707         set_capacity(disk, mddev->array_size<<1);
3708
3709         /* If we call blk_queue_make_request here, it will
3710          * re-initialise max_sectors etc which may have been
3711          * refined inside -> run.  So just set the bits we need to set.
3712          * Most initialisation happended when we called
3713          * blk_queue_make_request(..., md_fail_request)
3714          * earlier.
3715          */
3716         mddev->queue->queuedata = mddev;
3717         mddev->queue->make_request_fn = mddev->pers->make_request;
3718
3719         /* If there is a partially-recovered drive we need to
3720          * start recovery here.  If we leave it to md_check_recovery,
3721          * it will remove the drives and not do the right thing
3722          */
3723         if (mddev->degraded && !mddev->sync_thread) {
3724                 struct list_head *rtmp;
3725                 int spares = 0;
3726                 rdev_for_each(rdev, rtmp, mddev)
3727                         if (rdev->raid_disk >= 0 &&
3728                             !test_bit(In_sync, &rdev->flags) &&
3729                             !test_bit(Faulty, &rdev->flags))
3730                                 /* complete an interrupted recovery */
3731                                 spares++;
3732                 if (spares && mddev->pers->sync_request) {
3733                         mddev->recovery = 0;
3734                         set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
3735                         mddev->sync_thread = md_register_thread(md_do_sync,
3736                                                                 mddev,
3737                                                                 "%s_resync");
3738                         if (!mddev->sync_thread) {
3739                                 printk(KERN_ERR "%s: could not start resync"
3740                                        " thread...\n",
3741                                        mdname(mddev));
3742                                 /* leave the spares where they are, it shouldn't hurt */
3743                                 mddev->recovery = 0;
3744                         }
3745                 }
3746         }
3747         md_wakeup_thread(mddev->thread);
3748         md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
3749
3750         mddev->changed = 1;
3751         md_new_event(mddev);
3752         sysfs_notify(&mddev->kobj, NULL, "array_state");
3753         sysfs_notify(&mddev->kobj, NULL, "sync_action");
3754         sysfs_notify(&mddev->kobj, NULL, "degraded");
3755         kobject_uevent(&mddev->gendisk->dev.kobj, KOBJ_CHANGE);
3756         return 0;
3757 }
3758
3759 static int restart_array(mddev_t *mddev)
3760 {
3761         struct gendisk *disk = mddev->gendisk;
3762
3763         /* Complain if it has no devices */
3764         if (list_empty(&mddev->disks))
3765                 return -ENXIO;
3766         if (!mddev->pers)
3767                 return -EINVAL;
3768         if (!mddev->ro)
3769                 return -EBUSY;
3770         mddev->safemode = 0;
3771         mddev->ro = 0;
3772         set_disk_ro(disk, 0);
3773         printk(KERN_INFO "md: %s switched to read-write mode.\n",
3774                 mdname(mddev));
3775         /* Kick recovery or resync if necessary */
3776         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3777         md_wakeup_thread(mddev->thread);
3778         md_wakeup_thread(mddev->sync_thread);
3779         sysfs_notify(&mddev->kobj, NULL, "array_state");
3780         return 0;
3781 }
3782
3783 /* similar to deny_write_access, but accounts for our holding a reference
3784  * to the file ourselves */
3785 static int deny_bitmap_write_access(struct file * file)
3786 {
3787         struct inode *inode = file->f_mapping->host;
3788
3789         spin_lock(&inode->i_lock);
3790         if (atomic_read(&inode->i_writecount) > 1) {
3791                 spin_unlock(&inode->i_lock);
3792                 return -ETXTBSY;
3793         }
3794         atomic_set(&inode->i_writecount, -1);
3795         spin_unlock(&inode->i_lock);
3796
3797         return 0;
3798 }
3799
3800 static void restore_bitmap_write_access(struct file *file)
3801 {
3802         struct inode *inode = file->f_mapping->host;
3803
3804         spin_lock(&inode->i_lock);
3805         atomic_set(&inode->i_writecount, 1);
3806         spin_unlock(&inode->i_lock);
3807 }
3808
3809 /* mode:
3810  *   0 - completely stop and dis-assemble array
3811  *   1 - switch to readonly
3812  *   2 - stop but do not disassemble array
3813  */
3814 static int do_md_stop(mddev_t * mddev, int mode, int is_open)
3815 {
3816         int err = 0;
3817         struct gendisk *disk = mddev->gendisk;
3818
3819         if (atomic_read(&mddev->active) > 1 + is_open) {
3820                 printk("md: %s still in use.\n",mdname(mddev));
3821                 return -EBUSY;
3822         }
3823
3824         if (mddev->pers) {
3825
3826                 if (mddev->sync_thread) {
3827                         set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3828                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3829                         md_unregister_thread(mddev->sync_thread);
3830                         mddev->sync_thread = NULL;
3831                 }
3832
3833                 del_timer_sync(&mddev->safemode_timer);
3834
3835                 invalidate_partition(disk, 0);
3836
3837                 switch(mode) {
3838                 case 1: /* readonly */
3839                         err  = -ENXIO;
3840                         if (mddev->ro==1)
3841                                 goto out;
3842                         mddev->ro = 1;
3843                         break;
3844                 case 0: /* disassemble */
3845                 case 2: /* stop */
3846                         bitmap_flush(mddev);
3847                         md_super_wait(mddev);
3848                         if (mddev->ro)
3849                                 set_disk_ro(disk, 0);
3850                         blk_queue_make_request(mddev->queue, md_fail_request);
3851                         mddev->pers->stop(mddev);
3852                         mddev->queue->merge_bvec_fn = NULL;
3853                         mddev->queue->unplug_fn = NULL;
3854                         mddev->queue->backing_dev_info.congested_fn = NULL;
3855                         if (mddev->pers->sync_request)
3856                                 sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
3857
3858                         module_put(mddev->pers->owner);
3859                         mddev->pers = NULL;
3860                         /* tell userspace to handle 'inactive' */
3861                         sysfs_notify(&mddev->kobj, NULL, "array_state");
3862
3863                         set_capacity(disk, 0);
3864                         mddev->changed = 1;
3865
3866                         if (mddev->ro)
3867                                 mddev->ro = 0;
3868                 }
3869                 if (!mddev->in_sync || mddev->flags) {
3870                         /* mark array as shutdown cleanly */
3871                         mddev->in_sync = 1;
3872                         md_update_sb(mddev, 1);
3873                 }
3874                 if (mode == 1)
3875                         set_disk_ro(disk, 1);
3876                 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3877         }
3878
3879         /*
3880          * Free resources if final stop
3881          */
3882         if (mode == 0) {
3883                 mdk_rdev_t *rdev;
3884                 struct list_head *tmp;
3885
3886                 printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
3887
3888                 bitmap_destroy(mddev);
3889                 if (mddev->bitmap_file) {
3890                         restore_bitmap_write_access(mddev->bitmap_file);
3891                         fput(mddev->bitmap_file);
3892                         mddev->bitmap_file = NULL;
3893                 }
3894                 mddev->bitmap_offset = 0;
3895
3896                 rdev_for_each(rdev, tmp, mddev)
3897                         if (rdev->raid_disk >= 0) {
3898                                 char nm[20];
3899                                 sprintf(nm, "rd%d", rdev->raid_disk);
3900                                 sysfs_remove_link(&mddev->kobj, nm);
3901                         }
3902
3903                 /* make sure all md_delayed_delete calls have finished */
3904                 flush_scheduled_work();
3905
3906                 export_array(mddev);
3907
3908                 mddev->array_size = 0;
3909                 mddev->size = 0;
3910                 mddev->raid_disks = 0;
3911                 mddev->recovery_cp = 0;
3912                 mddev->resync_min = 0;
3913                 mddev->resync_max = MaxSector;
3914                 mddev->reshape_position = MaxSector;
3915                 mddev->external = 0;
3916                 mddev->persistent = 0;
3917                 mddev->level = LEVEL_NONE;
3918                 mddev->clevel[0] = 0;
3919                 mddev->flags = 0;
3920                 mddev->ro = 0;
3921                 mddev->metadata_type[0] = 0;
3922                 mddev->chunk_size = 0;
3923                 mddev->ctime = mddev->utime = 0;
3924                 mddev->layout = 0;
3925                 mddev->max_disks = 0;
3926                 mddev->events = 0;
3927                 mddev->delta_disks = 0;
3928                 mddev->new_level = LEVEL_NONE;
3929                 mddev->new_layout = 0;
3930                 mddev->new_chunk = 0;
3931                 mddev->curr_resync = 0;
3932                 mddev->resync_mismatches = 0;
3933                 mddev->suspend_lo = mddev->suspend_hi = 0;
3934                 mddev->sync_speed_min = mddev->sync_speed_max = 0;
3935                 mddev->recovery = 0;
3936                 mddev->in_sync = 0;
3937                 mddev->changed = 0;
3938                 mddev->degraded = 0;
3939                 mddev->barriers_work = 0;
3940                 mddev->safemode = 0;
3941
3942         } else if (mddev->pers)
3943                 printk(KERN_INFO "md: %s switched to read-only mode.\n",
3944                         mdname(mddev));
3945         err = 0;
3946         md_new_event(mddev);
3947         sysfs_notify(&mddev->kobj, NULL, "array_state");
3948 out:
3949         return err;
3950 }
3951
3952 #ifndef MODULE
3953 static void autorun_array(mddev_t *mddev)
3954 {
3955         mdk_rdev_t *rdev;
3956         struct list_head *tmp;
3957         int err;
3958
3959         if (list_empty(&mddev->disks))
3960                 return;
3961
3962         printk(KERN_INFO "md: running: ");
3963
3964         rdev_for_each(rdev, tmp, mddev) {
3965                 char b[BDEVNAME_SIZE];
3966                 printk("<%s>", bdevname(rdev->bdev,b));
3967         }
3968         printk("\n");
3969
3970         err = do_md_run (mddev);
3971         if (err) {
3972                 printk(KERN_WARNING "md: do_md_run() returned %d\n", err);
3973                 do_md_stop (mddev, 0, 0);
3974         }
3975 }
3976
3977 /*
3978  * lets try to run arrays based on all disks that have arrived
3979  * until now. (those are in pending_raid_disks)
3980  *
3981  * the method: pick the first pending disk, collect all disks with
3982  * the same UUID, remove all from the pending list and put them into
3983  * the 'same_array' list. Then order this list based on superblock
3984  * update time (freshest comes first), kick out 'old' disks and
3985  * compare superblocks. If everything's fine then run it.
3986  *
3987  * If "unit" is allocated, then bump its reference count
3988  */
3989 static void autorun_devices(int part)
3990 {
3991         struct list_head *tmp;
3992         mdk_rdev_t *rdev0, *rdev;
3993         mddev_t *mddev;
3994         char b[BDEVNAME_SIZE];
3995
3996         printk(KERN_INFO "md: autorun ...\n");
3997         while (!list_empty(&pending_raid_disks)) {
3998                 int unit;
3999                 dev_t dev;
4000                 LIST_HEAD(candidates);
4001                 rdev0 = list_entry(pending_raid_disks.next,
4002                                          mdk_rdev_t, same_set);
4003
4004                 printk(KERN_INFO "md: considering %s ...\n",
4005                         bdevname(rdev0->bdev,b));
4006                 INIT_LIST_HEAD(&candidates);
4007                 rdev_for_each_list(rdev, tmp, pending_raid_disks)
4008                         if (super_90_load(rdev, rdev0, 0) >= 0) {
4009                                 printk(KERN_INFO "md:  adding %s ...\n",
4010                                         bdevname(rdev->bdev,b));
4011                                 list_move(&rdev->same_set, &candidates);
4012                         }
4013                 /*
4014                  * now we have a set of devices, with all of them having
4015                  * mostly sane superblocks. It's time to allocate the
4016                  * mddev.
4017                  */
4018                 if (part) {
4019                         dev = MKDEV(mdp_major,
4020                                     rdev0->preferred_minor << MdpMinorShift);
4021                         unit = MINOR(dev) >> MdpMinorShift;
4022                 } else {
4023                         dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
4024                         unit = MINOR(dev);
4025                 }
4026                 if (rdev0->preferred_minor != unit) {
4027                         printk(KERN_INFO "md: unit number in %s is bad: %d\n",
4028                                bdevname(rdev0->bdev, b), rdev0->preferred_minor);
4029                         break;
4030                 }
4031
4032                 md_probe(dev, NULL, NULL);
4033                 mddev = mddev_find(dev);
4034                 if (!mddev || !mddev->gendisk) {
4035                         if (mddev)
4036                                 mddev_put(mddev);
4037                         printk(KERN_ERR
4038                                 "md: cannot allocate memory for md drive.\n");
4039                         break;
4040                 }
4041                 if (mddev_lock(mddev))
4042                         printk(KERN_WARNING "md: %s locked, cannot run\n",
4043                                mdname(mddev));
4044                 else if (mddev->raid_disks || mddev->major_version
4045                          || !list_empty(&mddev->disks)) {
4046                         printk(KERN_WARNING
4047                                 "md: %s already running, cannot run %s\n",
4048                                 mdname(mddev), bdevname(rdev0->bdev,b));
4049                         mddev_unlock(mddev);
4050                 } else {
4051                         printk(KERN_INFO "md: created %s\n", mdname(mddev));
4052                         mddev->persistent = 1;
4053                         rdev_for_each_list(rdev, tmp, candidates) {
4054                                 list_del_init(&rdev->same_set);
4055                                 if (bind_rdev_to_array(rdev, mddev))
4056                                         export_rdev(rdev);
4057                         }
4058                         autorun_array(mddev);
4059                         mddev_unlock(mddev);
4060                 }
4061                 /* on success, candidates will be empty, on error
4062                  * it won't...
4063                  */
4064                 rdev_for_each_list(rdev, tmp, candidates)
4065                         export_rdev(rdev);
4066                 mddev_put(mddev);
4067         }
4068         printk(KERN_INFO "md: ... autorun DONE.\n");
4069 }
4070 #endif /* !MODULE */
4071
4072 static int get_version(void __user * arg)
4073 {
4074         mdu_version_t ver;
4075
4076         ver.major = MD_MAJOR_VERSION;
4077         ver.minor = MD_MINOR_VERSION;
4078         ver.patchlevel = MD_PATCHLEVEL_VERSION;
4079
4080         if (copy_to_user(arg, &ver, sizeof(ver)))
4081                 return -EFAULT;
4082
4083         return 0;
4084 }
4085
4086 static int get_array_info(mddev_t * mddev, void __user * arg)
4087 {
4088         mdu_array_info_t info;
4089         int nr,working,active,failed,spare;
4090         mdk_rdev_t *rdev;
4091         struct list_head *tmp;
4092
4093         nr=working=active=failed=spare=0;
4094         rdev_for_each(rdev, tmp, mddev) {
4095                 nr++;
4096                 if (test_bit(Faulty, &rdev->flags))
4097                         failed++;
4098                 else {
4099                         working++;
4100                         if (test_bit(In_sync, &rdev->flags))
4101                                 active++;
4102                         else
4103                                 spare++;
4104                 }
4105         }
4106
4107         info.major_version = mddev->major_version;
4108         info.minor_version = mddev->minor_version;
4109         info.patch_version = MD_PATCHLEVEL_VERSION;
4110         info.ctime         = mddev->ctime;
4111         info.level         = mddev->level;
4112         info.size          = mddev->size;
4113         if (info.size != mddev->size) /* overflow */
4114                 info.size = -1;
4115         info.nr_disks      = nr;
4116         info.raid_disks    = mddev->raid_disks;
4117         info.md_minor      = mddev->md_minor;
4118         info.not_persistent= !mddev->persistent;
4119
4120         info.utime         = mddev->utime;
4121         info.state         = 0;
4122         if (mddev->in_sync)
4123                 info.state = (1<<MD_SB_CLEAN);
4124         if (mddev->bitmap && mddev->bitmap_offset)
4125                 info.state = (1<<MD_SB_BITMAP_PRESENT);
4126         info.active_disks  = active;
4127         info.working_disks = working;
4128         info.failed_disks  = failed;
4129         info.spare_disks   = spare;
4130
4131         info.layout        = mddev->layout;
4132         info.chunk_size    = mddev->chunk_size;
4133
4134         if (copy_to_user(arg, &info, sizeof(info)))
4135                 return -EFAULT;
4136
4137         return 0;
4138 }
4139
4140 static int get_bitmap_file(mddev_t * mddev, void __user * arg)
4141 {
4142         mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
4143         char *ptr, *buf = NULL;
4144         int err = -ENOMEM;
4145
4146         if (md_allow_write(mddev))
4147                 file = kmalloc(sizeof(*file), GFP_NOIO);
4148         else
4149                 file = kmalloc(sizeof(*file), GFP_KERNEL);
4150
4151         if (!file)
4152                 goto out;
4153
4154         /* bitmap disabled, zero the first byte and copy out */
4155         if (!mddev->bitmap || !mddev->bitmap->file) {
4156                 file->pathname[0] = '\0';
4157                 goto copy_out;
4158         }
4159
4160         buf = kmalloc(sizeof(file->pathname), GFP_KERNEL);
4161         if (!buf)
4162                 goto out;
4163
4164         ptr = d_path(&mddev->bitmap->file->f_path, buf, sizeof(file->pathname));
4165         if (IS_ERR(ptr))
4166                 goto out;
4167
4168         strcpy(file->pathname, ptr);
4169
4170 copy_out:
4171         err = 0;
4172         if (copy_to_user(arg, file, sizeof(*file)))
4173                 err = -EFAULT;
4174 out:
4175         kfree(buf);
4176         kfree(file);
4177         return err;
4178 }
4179
4180 static int get_disk_info(mddev_t * mddev, void __user * arg)
4181 {
4182         mdu_disk_info_t info;
4183         mdk_rdev_t *rdev;
4184
4185         if (copy_from_user(&info, arg, sizeof(info)))
4186                 return -EFAULT;
4187
4188         rdev = find_rdev_nr(mddev, info.number);
4189         if (rdev) {
4190                 info.major = MAJOR(rdev->bdev->bd_dev);
4191                 info.minor = MINOR(rdev->bdev->bd_dev);
4192                 info.raid_disk = rdev->raid_disk;
4193                 info.state = 0;
4194                 if (test_bit(Faulty, &rdev->flags))
4195                         info.state |= (1<<MD_DISK_FAULTY);
4196                 else if (test_bit(In_sync, &rdev->flags)) {
4197                         info.state |= (1<<MD_DISK_ACTIVE);
4198                         info.state |= (1<<MD_DISK_SYNC);
4199                 }
4200                 if (test_bit(WriteMostly, &rdev->flags))
4201                         info.state |= (1<<MD_DISK_WRITEMOSTLY);
4202         } else {
4203                 info.major = info.minor = 0;
4204                 info.raid_disk = -1;
4205                 info.state = (1<<MD_DISK_REMOVED);
4206         }
4207
4208         if (copy_to_user(arg, &info, sizeof(info)))
4209                 return -EFAULT;
4210
4211         return 0;
4212 }
4213
4214 static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
4215 {
4216         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
4217         mdk_rdev_t *rdev;
4218         dev_t dev = MKDEV(info->major,info->minor);
4219
4220         if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
4221                 return -EOVERFLOW;
4222
4223         if (!mddev->raid_disks) {
4224                 int err;
4225                 /* expecting a device which has a superblock */
4226                 rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
4227                 if (IS_ERR(rdev)) {
4228                         printk(KERN_WARNING
4229                                 "md: md_import_device returned %ld\n",
4230                                 PTR_ERR(rdev));
4231                         return PTR_ERR(rdev);
4232                 }
4233                 if (!list_empty(&mddev->disks)) {
4234                         mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
4235                                                         mdk_rdev_t, same_set);
4236                         int err = super_types[mddev->major_version]
4237                                 .load_super(rdev, rdev0, mddev->minor_version);
4238                         if (err < 0) {
4239                                 printk(KERN_WARNING
4240                                         "md: %s has different UUID to %s\n",
4241                                         bdevname(rdev->bdev,b),
4242                                         bdevname(rdev0->bdev,b2));
4243                                 export_rdev(rdev);
4244                                 return -EINVAL;
4245                         }
4246                 }
4247                 err = bind_rdev_to_array(rdev, mddev);
4248                 if (err)
4249                         export_rdev(rdev);
4250                 return err;
4251         }
4252
4253         /*
4254          * add_new_disk can be used once the array is assembled
4255          * to add "hot spares".  They must already have a superblock
4256          * written
4257          */
4258         if (mddev->pers) {
4259                 int err;
4260                 if (!mddev->pers->hot_add_disk) {
4261                         printk(KERN_WARNING
4262                                 "%s: personality does not support diskops!\n",
4263                                mdname(mddev));
4264                         return -EINVAL;
4265                 }
4266                 if (mddev->persistent)
4267                         rdev = md_import_device(dev, mddev->major_version,
4268                                                 mddev->minor_version);
4269                 else
4270                         rdev = md_import_device(dev, -1, -1);
4271                 if (IS_ERR(rdev)) {
4272                         printk(KERN_WARNING
4273                                 "md: md_import_device returned %ld\n",
4274                                 PTR_ERR(rdev));
4275                         return PTR_ERR(rdev);
4276                 }
4277                 /* set save_raid_disk if appropriate */
4278                 if (!mddev->persistent) {
4279                         if (info->state & (1<<MD_DISK_SYNC)  &&
4280                             info->raid_disk < mddev->raid_disks)
4281                                 rdev->raid_disk = info->raid_disk;
4282                         else
4283                                 rdev->raid_disk = -1;
4284                 } else
4285                         super_types[mddev->major_version].
4286                                 validate_super(mddev, rdev);
4287                 rdev->saved_raid_disk = rdev->raid_disk;
4288
4289                 clear_bit(In_sync, &rdev->flags); /* just to be sure */
4290                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
4291                         set_bit(WriteMostly, &rdev->flags);
4292
4293                 rdev->raid_disk = -1;
4294                 err = bind_rdev_to_array(rdev, mddev);
4295                 if (!err && !mddev->pers->hot_remove_disk) {
4296                         /* If there is hot_add_disk but no hot_remove_disk
4297                          * then added disks for geometry changes,
4298                          * and should be added immediately.
4299                          */
4300                         super_types[mddev->major_version].
4301                                 validate_super(mddev, rdev);
4302                         err = mddev->pers->hot_add_disk(mddev, rdev);
4303                         if (err)
4304                                 unbind_rdev_from_array(rdev);
4305                 }
4306                 if (err)
4307                         export_rdev(rdev);
4308                 else
4309                         sysfs_notify(&rdev->kobj, NULL, "state");
4310
4311                 md_update_sb(mddev, 1);
4312                 if (mddev->degraded)
4313                         set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
4314                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4315                 md_wakeup_thread(mddev->thread);
4316                 return err;
4317         }
4318
4319         /* otherwise, add_new_disk is only allowed
4320          * for major_version==0 superblocks
4321          */
4322         if (mddev->major_version != 0) {
4323                 printk(KERN_WARNING "%s: ADD_NEW_DISK not supported\n",
4324                        mdname(mddev));
4325                 return -EINVAL;
4326         }
4327
4328         if (!(info->state & (1<<MD_DISK_FAULTY))) {
4329                 int err;
4330                 rdev = md_import_device (dev, -1, 0);
4331                 if (IS_ERR(rdev)) {
4332                         printk(KERN_WARNING
4333                                 "md: error, md_import_device() returned %ld\n",
4334                                 PTR_ERR(rdev));
4335                         return PTR_ERR(rdev);
4336                 }
4337                 rdev->desc_nr = info->number;
4338                 if (info->raid_disk < mddev->raid_disks)
4339                         rdev->raid_disk = info->raid_disk;
4340                 else
4341                         rdev->raid_disk = -1;
4342
4343                 if (rdev->raid_disk < mddev->raid_disks)
4344                         if (info->state & (1<<MD_DISK_SYNC))
4345                                 set_bit(In_sync, &rdev->flags);
4346
4347                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
4348                         set_bit(WriteMostly, &rdev->flags);
4349
4350                 if (!mddev->persistent) {
4351                         printk(KERN_INFO "md: nonpersistent superblock ...\n");
4352                         rdev->sb_start = rdev->bdev->bd_inode->i_size / 512;
4353                 } else
4354                         rdev->sb_start = calc_dev_sboffset(rdev->bdev);
4355                 rdev->size = calc_num_sectors(rdev, mddev->chunk_size) / 2;
4356
4357                 err = bind_rdev_to_array(rdev, mddev);
4358                 if (err) {
4359                         export_rdev(rdev);
4360                         return err;
4361                 }
4362         }
4363
4364         return 0;
4365 }
4366
4367 static int hot_remove_disk(mddev_t * mddev, dev_t dev)
4368 {
4369         char b[BDEVNAME_SIZE];
4370         mdk_rdev_t *rdev;
4371
4372         rdev = find_rdev(mddev, dev);
4373         if (!rdev)
4374                 return -ENXIO;
4375
4376         if (rdev->raid_disk >= 0)
4377                 goto busy;
4378
4379         kick_rdev_from_array(rdev);
4380         md_update_sb(mddev, 1);
4381         md_new_event(mddev);
4382
4383         return 0;
4384 busy:
4385         printk(KERN_WARNING "md: cannot remove active disk %s from %s ...\n",
4386                 bdevname(rdev->bdev,b), mdname(mddev));
4387         return -EBUSY;
4388 }
4389
4390 static int hot_add_disk(mddev_t * mddev, dev_t dev)
4391 {
4392         char b[BDEVNAME_SIZE];
4393         int err;
4394         mdk_rdev_t *rdev;
4395
4396         if (!mddev->pers)
4397                 return -ENODEV;
4398
4399         if (mddev->major_version != 0) {
4400                 printk(KERN_WARNING "%s: HOT_ADD may only be used with"
4401                         " version-0 superblocks.\n",
4402                         mdname(mddev));
4403                 return -EINVAL;
4404         }
4405         if (!mddev->pers->hot_add_disk) {
4406                 printk(KERN_WARNING
4407                         "%s: personality does not support diskops!\n",
4408                         mdname(mddev));
4409                 return -EINVAL;
4410         }
4411
4412         rdev = md_import_device (dev, -1, 0);
4413         if (IS_ERR(rdev)) {
4414                 printk(KERN_WARNING
4415                         "md: error, md_import_device() returned %ld\n",
4416                         PTR_ERR(rdev));
4417                 return -EINVAL;
4418         }
4419
4420         if (mddev->persistent)
4421                 rdev->sb_start = calc_dev_sboffset(rdev->bdev);
4422         else
4423                 rdev->sb_start = rdev->bdev->bd_inode->i_size / 512;
4424
4425         rdev->size = calc_num_sectors(rdev, mddev->chunk_size) / 2;
4426
4427         if (test_bit(Faulty, &rdev->flags)) {
4428                 printk(KERN_WARNING
4429                         "md: can not hot-add faulty %s disk to %s!\n",
4430                         bdevname(rdev->bdev,b), mdname(mddev));
4431                 err = -EINVAL;
4432                 goto abort_export;
4433         }
4434         clear_bit(In_sync, &rdev->flags);
4435         rdev->desc_nr = -1;
4436         rdev->saved_raid_disk = -1;
4437         err = bind_rdev_to_array(rdev, mddev);
4438         if (err)
4439                 goto abort_export;
4440
4441         /*
4442          * The rest should better be atomic, we can have disk failures
4443          * noticed in interrupt contexts ...
4444          */
4445
4446         if (rdev->desc_nr == mddev->max_disks) {
4447                 printk(KERN_WARNING "%s: can not hot-add to full array!\n",
4448                         mdname(mddev));
4449                 err = -EBUSY;
4450                 goto abort_unbind_export;
4451         }
4452
4453         rdev->raid_disk = -1;
4454
4455         md_update_sb(mddev, 1);
4456
4457         /*
4458          * Kick recovery, maybe this spare has to be added to the
4459          * array immediately.
4460          */
4461         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4462         md_wakeup_thread(mddev->thread);
4463         md_new_event(mddev);
4464         return 0;
4465
4466 abort_unbind_export:
4467         unbind_rdev_from_array(rdev);
4468
4469 abort_export:
4470         export_rdev(rdev);
4471         return err;
4472 }
4473
4474 static int set_bitmap_file(mddev_t *mddev, int fd)
4475 {
4476         int err;
4477
4478         if (mddev->pers) {
4479                 if (!mddev->pers->quiesce)
4480                         return -EBUSY;
4481                 if (mddev->recovery || mddev->sync_thread)
4482                         return -EBUSY;
4483                 /* we should be able to change the bitmap.. */
4484         }
4485
4486
4487         if (fd >= 0) {
4488                 if (mddev->bitmap)
4489                         return -EEXIST; /* cannot add when bitmap is present */
4490                 mddev->bitmap_file = fget(fd);
4491
4492                 if (mddev->bitmap_file == NULL) {
4493                         printk(KERN_ERR "%s: error: failed to get bitmap file\n",
4494                                mdname(mddev));
4495                         return -EBADF;
4496                 }
4497
4498                 err = deny_bitmap_write_access(mddev->bitmap_file);
4499                 if (err) {
4500                         printk(KERN_ERR "%s: error: bitmap file is already in use\n",
4501                                mdname(mddev));
4502                         fput(mddev->bitmap_file);
4503                         mddev->bitmap_file = NULL;
4504                         return err;
4505                 }
4506                 mddev->bitmap_offset = 0; /* file overrides offset */
4507         } else if (mddev->bitmap == NULL)
4508                 return -ENOENT; /* cannot remove what isn't there */
4509         err = 0;
4510         if (mddev->pers) {
4511                 mddev->pers->quiesce(mddev, 1);
4512                 if (fd >= 0)
4513                         err = bitmap_create(mddev);
4514                 if (fd < 0 || err) {
4515                         bitmap_destroy(mddev);
4516                         fd = -1; /* make sure to put the file */
4517                 }
4518                 mddev->pers->quiesce(mddev, 0);
4519         }
4520         if (fd < 0) {
4521                 if (mddev->bitmap_file) {
4522                         restore_bitmap_write_access(mddev->bitmap_file);
4523                         fput(mddev->bitmap_file);
4524                 }
4525                 mddev->bitmap_file = NULL;
4526         }
4527
4528         return err;
4529 }
4530
4531 /*
4532  * set_array_info is used two different ways
4533  * The original usage is when creating a new array.
4534  * In this usage, raid_disks is > 0 and it together with
4535  *  level, size, not_persistent,layout,chunksize determine the
4536  *  shape of the array.
4537  *  This will always create an array with a type-0.90.0 superblock.
4538  * The newer usage is when assembling an array.
4539  *  In this case raid_disks will be 0, and the major_version field is
4540  *  use to determine which style super-blocks are to be found on the devices.
4541  *  The minor and patch _version numbers are also kept incase the
4542  *  super_block handler wishes to interpret them.
4543  */
4544 static int set_array_info(mddev_t * mddev, mdu_array_info_t *info)
4545 {
4546
4547         if (info->raid_disks == 0) {
4548                 /* just setting version number for superblock loading */
4549                 if (info->major_version < 0 ||
4550                     info->major_version >= ARRAY_SIZE(super_types) ||
4551                     super_types[info->major_version].name == NULL) {
4552                         /* maybe try to auto-load a module? */
4553                         printk(KERN_INFO
4554                                 "md: superblock version %d not known\n",
4555                                 info->major_version);
4556                         return -EINVAL;
4557                 }
4558                 mddev->major_version = info->major_version;
4559                 mddev->minor_version = info->minor_version;
4560                 mddev->patch_version = info->patch_version;
4561                 mddev->persistent = !info->not_persistent;
4562                 return 0;
4563         }
4564         mddev->major_version = MD_MAJOR_VERSION;
4565         mddev->minor_version = MD_MINOR_VERSION;
4566         mddev->patch_version = MD_PATCHLEVEL_VERSION;
4567         mddev->ctime         = get_seconds();
4568
4569         mddev->level         = info->level;
4570         mddev->clevel[0]     = 0;
4571         mddev->size          = info->size;
4572         mddev->raid_disks    = info->raid_disks;
4573         /* don't set md_minor, it is determined by which /dev/md* was
4574          * openned
4575          */
4576         if (info->state & (1<<MD_SB_CLEAN))
4577                 mddev->recovery_cp = MaxSector;
4578         else
4579                 mddev->recovery_cp = 0;
4580         mddev->persistent    = ! info->not_persistent;
4581         mddev->external      = 0;
4582
4583         mddev->layout        = info->layout;
4584         mddev->chunk_size    = info->chunk_size;
4585
4586         mddev->max_disks     = MD_SB_DISKS;
4587
4588         if (mddev->persistent)
4589                 mddev->flags         = 0;
4590         set_bit(MD_CHANGE_DEVS, &mddev->flags);
4591
4592         mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
4593         mddev->bitmap_offset = 0;
4594
4595         mddev->reshape_position = MaxSector;
4596
4597         /*
4598          * Generate a 128 bit UUID
4599          */
4600         get_random_bytes(mddev->uuid, 16);
4601
4602         mddev->new_level = mddev->level;
4603         mddev->new_chunk = mddev->chunk_size;
4604         mddev->new_layout = mddev->layout;
4605         mddev->delta_disks = 0;
4606
4607         return 0;
4608 }
4609
4610 static int update_size(mddev_t *mddev, sector_t num_sectors)
4611 {
4612         mdk_rdev_t * rdev;
4613         int rv;
4614         struct list_head *tmp;
4615         int fit = (num_sectors == 0);
4616
4617         if (mddev->pers->resize == NULL)
4618                 return -EINVAL;
4619         /* The "num_sectors" is the number of sectors of each device that
4620          * is used.  This can only make sense for arrays with redundancy.
4621          * linear and raid0 always use whatever space is available. We can only
4622          * consider changing this number if no resync or reconstruction is
4623          * happening, and if the new size is acceptable. It must fit before the
4624          * sb_start or, if that is <data_offset, it must fit before the size
4625          * of each device.  If num_sectors is zero, we find the largest size
4626          * that fits.
4627
4628          */
4629         if (mddev->sync_thread)
4630                 return -EBUSY;
4631         rdev_for_each(rdev, tmp, mddev) {
4632                 sector_t avail;
4633                 avail = rdev->size * 2;
4634
4635                 if (fit && (num_sectors == 0 || num_sectors > avail))
4636                         num_sectors = avail;
4637                 if (avail < num_sectors)
4638                         return -ENOSPC;
4639         }
4640         rv = mddev->pers->resize(mddev, num_sectors);
4641         if (!rv) {
4642                 struct block_device *bdev;
4643
4644                 bdev = bdget_disk(mddev->gendisk, 0);
4645                 if (bdev) {
4646                         mutex_lock(&bdev->bd_inode->i_mutex);
4647                         i_size_write(bdev->bd_inode, (loff_t)mddev->array_size << 10);
4648                         mutex_unlock(&bdev->bd_inode->i_mutex);
4649                         bdput(bdev);
4650                 }
4651         }
4652         return rv;
4653 }
4654
4655 static int update_raid_disks(mddev_t *mddev, int raid_disks)
4656 {
4657         int rv;
4658         /* change the number of raid disks */
4659         if (mddev->pers->check_reshape == NULL)
4660                 return -EINVAL;
4661         if (raid_disks <= 0 ||
4662             raid_disks >= mddev->max_disks)
4663                 return -EINVAL;
4664         if (mddev->sync_thread || mddev->reshape_position != MaxSector)
4665                 return -EBUSY;
4666         mddev->delta_disks = raid_disks - mddev->raid_disks;
4667
4668         rv = mddev->pers->check_reshape(mddev);
4669         return rv;
4670 }
4671
4672
4673 /*
4674  * update_array_info is used to change the configuration of an
4675  * on-line array.
4676  * The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
4677  * fields in the info are checked against the array.
4678  * Any differences that cannot be handled will cause an error.
4679  * Normally, only one change can be managed at a time.
4680  */
4681 static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
4682 {
4683         int rv = 0;
4684         int cnt = 0;
4685         int state = 0;
4686
4687         /* calculate expected state,ignoring low bits */
4688         if (mddev->bitmap && mddev->bitmap_offset)
4689                 state |= (1 << MD_SB_BITMAP_PRESENT);
4690
4691         if (mddev->major_version != info->major_version ||
4692             mddev->minor_version != info->minor_version ||
4693 /*          mddev->patch_version != info->patch_version || */
4694             mddev->ctime         != info->ctime         ||
4695             mddev->level         != info->level         ||
4696 /*          mddev->layout        != info->layout        || */
4697             !mddev->persistent   != info->not_persistent||
4698             mddev->chunk_size    != info->chunk_size    ||
4699             /* ignore bottom 8 bits of state, and allow SB_BITMAP_PRESENT to change */
4700             ((state^info->state) & 0xfffffe00)
4701                 )
4702                 return -EINVAL;
4703         /* Check there is only one change */
4704         if (info->size >= 0 && mddev->size != info->size) cnt++;
4705         if (mddev->raid_disks != info->raid_disks) cnt++;
4706         if (mddev->layout != info->layout) cnt++;
4707         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) cnt++;
4708         if (cnt == 0) return 0;
4709         if (cnt > 1) return -EINVAL;
4710
4711         if (mddev->layout != info->layout) {
4712                 /* Change layout
4713                  * we don't need to do anything at the md level, the
4714                  * personality will take care of it all.
4715                  */
4716                 if (mddev->pers->reconfig == NULL)
4717                         return -EINVAL;
4718                 else
4719                         return mddev->pers->reconfig(mddev, info->layout, -1);
4720         }
4721         if (info->size >= 0 && mddev->size != info->size)
4722                 rv = update_size(mddev, (sector_t)info->size * 2);
4723
4724         if (mddev->raid_disks    != info->raid_disks)
4725                 rv = update_raid_disks(mddev, info->raid_disks);
4726
4727         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) {
4728                 if (mddev->pers->quiesce == NULL)
4729                         return -EINVAL;
4730                 if (mddev->recovery || mddev->sync_thread)
4731                         return -EBUSY;
4732                 if (info->state & (1<<MD_SB_BITMAP_PRESENT)) {
4733                         /* add the bitmap */
4734                         if (mddev->bitmap)
4735                                 return -EEXIST;
4736                         if (mddev->default_bitmap_offset == 0)
4737                                 return -EINVAL;
4738                         mddev->bitmap_offset = mddev->default_bitmap_offset;
4739                         mddev->pers->quiesce(mddev, 1);
4740                         rv = bitmap_create(mddev);
4741                         if (rv)
4742                                 bitmap_destroy(mddev);
4743                         mddev->pers->quiesce(mddev, 0);
4744                 } else {
4745                         /* remove the bitmap */
4746                         if (!mddev->bitmap)
4747                                 return -ENOENT;
4748                         if (mddev->bitmap->file)
4749                                 return -EINVAL;
4750                         mddev->pers->quiesce(mddev, 1);
4751                         bitmap_destroy(mddev);
4752                         mddev->pers->quiesce(mddev, 0);
4753                         mddev->bitmap_offset = 0;
4754                 }
4755         }
4756         md_update_sb(mddev, 1);
4757         return rv;
4758 }
4759
4760 static int set_disk_faulty(mddev_t *mddev, dev_t dev)
4761 {
4762         mdk_rdev_t *rdev;
4763
4764         if (mddev->pers == NULL)
4765                 return -ENODEV;
4766
4767         rdev = find_rdev(mddev, dev);
4768         if (!rdev)
4769                 return -ENODEV;
4770
4771         md_error(mddev, rdev);
4772         return 0;
4773 }
4774
4775 /*
4776  * We have a problem here : there is no easy way to give a CHS
4777  * virtual geometry. We currently pretend that we have a 2 heads
4778  * 4 sectors (with a BIG number of cylinders...). This drives
4779  * dosfs just mad... ;-)
4780  */
4781 static int md_getgeo(struct block_device *bdev, struct hd_geometry *geo)
4782 {
4783         mddev_t *mddev = bdev->bd_disk->private_data;
4784
4785         geo->heads = 2;
4786         geo->sectors = 4;
4787         geo->cylinders = get_capacity(mddev->gendisk) / 8;
4788         return 0;
4789 }
4790
4791 static int md_ioctl(struct inode *inode, struct file *file,
4792                         unsigned int cmd, unsigned long arg)
4793 {
4794         int err = 0;
4795         void __user *argp = (void __user *)arg;
4796         mddev_t *mddev = NULL;
4797
4798         if (!capable(CAP_SYS_ADMIN))
4799                 return -EACCES;
4800
4801         /*
4802          * Commands dealing with the RAID driver but not any
4803          * particular array:
4804          */
4805         switch (cmd)
4806         {
4807                 case RAID_VERSION:
4808                         err = get_version(argp);
4809                         goto done;
4810
4811                 case PRINT_RAID_DEBUG:
4812                         err = 0;
4813                         md_print_devices();
4814                         goto done;
4815
4816 #ifndef MODULE
4817                 case RAID_AUTORUN:
4818                         err = 0;
4819                         autostart_arrays(arg);
4820                         goto done;
4821 #endif
4822                 default:;
4823         }
4824
4825         /*
4826          * Commands creating/starting a new array:
4827          */
4828
4829         mddev = inode->i_bdev->bd_disk->private_data;
4830
4831         if (!mddev) {
4832                 BUG();
4833                 goto abort;
4834         }
4835
4836         err = mddev_lock(mddev);
4837         if (err) {
4838                 printk(KERN_INFO
4839                         "md: ioctl lock interrupted, reason %d, cmd %d\n",
4840                         err, cmd);
4841                 goto abort;
4842         }
4843
4844         switch (cmd)
4845         {
4846                 case SET_ARRAY_INFO:
4847                         {
4848                                 mdu_array_info_t info;
4849                                 if (!arg)
4850                                         memset(&info, 0, sizeof(info));
4851                                 else if (copy_from_user(&info, argp, sizeof(info))) {
4852                                         err = -EFAULT;
4853                                         goto abort_unlock;
4854                                 }
4855                                 if (mddev->pers) {
4856                                         err = update_array_info(mddev, &info);
4857                                         if (err) {
4858                                                 printk(KERN_WARNING "md: couldn't update"
4859                                                        " array info. %d\n", err);
4860                                                 goto abort_unlock;
4861                                         }
4862                                         goto done_unlock;
4863                                 }
4864                                 if (!list_empty(&mddev->disks)) {
4865                                         printk(KERN_WARNING
4866                                                "md: array %s already has disks!\n",
4867                                                mdname(mddev));
4868                                         err = -EBUSY;
4869                                         goto abort_unlock;
4870                                 }
4871                                 if (mddev->raid_disks) {
4872                                         printk(KERN_WARNING
4873                                                "md: array %s already initialised!\n",
4874                                                mdname(mddev));
4875                                         err = -EBUSY;
4876                                         goto abort_unlock;
4877                                 }
4878                                 err = set_array_info(mddev, &info);
4879                                 if (err) {
4880                                         printk(KERN_WARNING "md: couldn't set"
4881                                                " array info. %d\n", err);
4882                                         goto abort_unlock;
4883                                 }
4884                         }
4885                         goto done_unlock;
4886
4887                 default:;
4888         }
4889
4890         /*
4891          * Commands querying/configuring an existing array:
4892          */
4893         /* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
4894          * RUN_ARRAY, and GET_ and SET_BITMAP_FILE are allowed */
4895         if ((!mddev->raid_disks && !mddev->external)
4896             && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
4897             && cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE
4898             && cmd != GET_BITMAP_FILE) {
4899                 err = -ENODEV;
4900                 goto abort_unlock;
4901         }
4902
4903         /*
4904          * Commands even a read-only array can execute:
4905          */
4906         switch (cmd)
4907         {
4908                 case GET_ARRAY_INFO:
4909                         err = get_array_info(mddev, argp);
4910                         goto done_unlock;
4911
4912                 case GET_BITMAP_FILE:
4913                         err = get_bitmap_file(mddev, argp);
4914                         goto done_unlock;
4915
4916                 case GET_DISK_INFO:
4917                         err = get_disk_info(mddev, argp);
4918                         goto done_unlock;
4919
4920                 case RESTART_ARRAY_RW:
4921                         err = restart_array(mddev);
4922                         goto done_unlock;
4923
4924                 case STOP_ARRAY:
4925                         err = do_md_stop (mddev, 0, 1);
4926                         goto done_unlock;
4927
4928                 case STOP_ARRAY_RO:
4929                         err = do_md_stop (mddev, 1, 1);
4930                         goto done_unlock;
4931
4932         }
4933
4934         /*
4935          * The remaining ioctls are changing the state of the
4936          * superblock, so we do not allow them on read-only arrays.
4937          * However non-MD ioctls (e.g. get-size) will still come through
4938          * here and hit the 'default' below, so only disallow
4939          * 'md' ioctls, and switch to rw mode if started auto-readonly.
4940          */
4941         if (_IOC_TYPE(cmd) == MD_MAJOR && mddev->ro && mddev->pers) {
4942                 if (mddev->ro == 2) {
4943                         mddev->ro = 0;
4944                         sysfs_notify(&mddev->kobj, NULL, "array_state");
4945                         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4946                         md_wakeup_thread(mddev->thread);
4947                 } else {
4948                         err = -EROFS;
4949                         goto abort_unlock;
4950                 }
4951         }
4952
4953         switch (cmd)
4954         {
4955                 case ADD_NEW_DISK:
4956                 {
4957                         mdu_disk_info_t info;
4958                         if (copy_from_user(&info, argp, sizeof(info)))
4959                                 err = -EFAULT;
4960                         else
4961                                 err = add_new_disk(mddev, &info);
4962                         goto done_unlock;
4963                 }
4964
4965                 case HOT_REMOVE_DISK:
4966                         err = hot_remove_disk(mddev, new_decode_dev(arg));
4967                         goto done_unlock;
4968
4969                 case HOT_ADD_DISK:
4970                         err = hot_add_disk(mddev, new_decode_dev(arg));
4971                         goto done_unlock;
4972
4973                 case SET_DISK_FAULTY:
4974                         err = set_disk_faulty(mddev, new_decode_dev(arg));
4975                         goto done_unlock;
4976
4977                 case RUN_ARRAY:
4978                         err = do_md_run (mddev);
4979                         goto done_unlock;
4980
4981                 case SET_BITMAP_FILE:
4982                         err = set_bitmap_file(mddev, (int)arg);
4983                         goto done_unlock;
4984
4985                 default:
4986                         err = -EINVAL;
4987                         goto abort_unlock;
4988         }
4989
4990 done_unlock:
4991 abort_unlock:
4992         mddev_unlock(mddev);
4993
4994         return err;
4995 done:
4996         if (err)
4997                 MD_BUG();
4998 abort:
4999         return err;
5000 }
5001
5002 static int md_open(struct inode *inode, struct file *file)
5003 {
5004         /*
5005          * Succeed if we can lock the mddev, which confirms that
5006          * it isn't being stopped right now.
5007          */
5008         mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
5009         int err;
5010
5011         if ((err = mutex_lock_interruptible_nested(&mddev->reconfig_mutex, 1)))
5012                 goto out;
5013
5014         err = 0;
5015         mddev_get(mddev);
5016         mddev_unlock(mddev);
5017
5018         check_disk_change(inode->i_bdev);
5019  out:
5020         return err;
5021 }
5022
5023 static int md_release(struct inode *inode, struct file * file)
5024 {
5025         mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
5026
5027         BUG_ON(!mddev);
5028         mddev_put(mddev);
5029
5030         return 0;
5031 }
5032
5033 static int md_media_changed(struct gendisk *disk)
5034 {
5035         mddev_t *mddev = disk->private_data;
5036
5037         return mddev->changed;
5038 }
5039
5040 static int md_revalidate(struct gendisk *disk)
5041 {
5042         mddev_t *mddev = disk->private_data;
5043
5044         mddev->changed = 0;
5045         return 0;
5046 }
5047 static struct block_device_operations md_fops =
5048 {
5049         .owner          = THIS_MODULE,
5050         .open           = md_open,
5051         .release        = md_release,
5052         .ioctl          = md_ioctl,
5053         .getgeo         = md_getgeo,
5054         .media_changed  = md_media_changed,
5055         .revalidate_disk= md_revalidate,
5056 };
5057
5058 static int md_thread(void * arg)
5059 {
5060         mdk_thread_t *thread = arg;
5061
5062         /*
5063          * md_thread is a 'system-thread', it's priority should be very
5064          * high. We avoid resource deadlocks individually in each
5065          * raid personality. (RAID5 does preallocation) We also use RR and
5066          * the very same RT priority as kswapd, thus we will never get
5067          * into a priority inversion deadlock.
5068          *
5069          * we definitely have to have equal or higher priority than
5070          * bdflush, otherwise bdflush will deadlock if there are too
5071          * many dirty RAID5 blocks.
5072          */
5073
5074         allow_signal(SIGKILL);
5075         while (!kthread_should_stop()) {
5076
5077                 /* We need to wait INTERRUPTIBLE so that
5078                  * we don't add to the load-average.
5079                  * That means we need to be sure no signals are
5080                  * pending
5081                  */
5082                 if (signal_pending(current))
5083                         flush_signals(current);
5084
5085                 wait_event_interruptible_timeout
5086                         (thread->wqueue,
5087                          test_bit(THREAD_WAKEUP, &thread->flags)
5088                          || kthread_should_stop(),
5089                          thread->timeout);
5090
5091                 clear_bit(THREAD_WAKEUP, &thread->flags);
5092
5093                 thread->run(thread->mddev);
5094         }
5095
5096         return 0;
5097 }
5098
5099 void md_wakeup_thread(mdk_thread_t *thread)
5100 {
5101         if (thread) {
5102                 dprintk("md: waking up MD thread %s.\n", thread->tsk->comm);
5103                 set_bit(THREAD_WAKEUP, &thread->flags);
5104                 wake_up(&thread->wqueue);
5105         }
5106 }
5107
5108 mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev,
5109                                  const char *name)
5110 {
5111         mdk_thread_t *thread;
5112
5113         thread = kzalloc(sizeof(mdk_thread_t), GFP_KERNEL);
5114         if (!thread)
5115                 return NULL;
5116
5117         init_waitqueue_head(&thread->wqueue);
5118
5119         thread->run = run;
5120         thread->mddev = mddev;
5121         thread->timeout = MAX_SCHEDULE_TIMEOUT;
5122         thread->tsk = kthread_run(md_thread, thread, name, mdname(thread->mddev));
5123         if (IS_ERR(thread->tsk)) {
5124                 kfree(thread);
5125                 return NULL;
5126         }
5127         return thread;
5128 }
5129
5130 void md_unregister_thread(mdk_thread_t *thread)
5131 {
5132         dprintk("interrupting MD-thread pid %d\n", task_pid_nr(thread->tsk));
5133
5134         kthread_stop(thread->tsk);
5135         kfree(thread);
5136 }
5137
5138 void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
5139 {
5140         if (!mddev) {
5141                 MD_BUG();
5142                 return;
5143         }
5144
5145         if (!rdev || test_bit(Faulty, &rdev->flags))
5146                 return;
5147
5148         if (mddev->external)
5149                 set_bit(Blocked, &rdev->flags);
5150 /*
5151         dprintk("md_error dev:%s, rdev:(%d:%d), (caller: %p,%p,%p,%p).\n",
5152                 mdname(mddev),
5153                 MAJOR(rdev->bdev->bd_dev), MINOR(rdev->bdev->bd_dev),
5154                 __builtin_return_address(0),__builtin_return_address(1),
5155                 __builtin_return_address(2),__builtin_return_address(3));
5156 */
5157         if (!mddev->pers)
5158                 return;
5159         if (!mddev->pers->error_handler)
5160                 return;
5161         mddev->pers->error_handler(mddev,rdev);
5162         if (mddev->degraded)
5163                 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
5164         set_bit(StateChanged, &rdev->flags);
5165         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
5166         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5167         md_wakeup_thread(mddev->thread);
5168         md_new_event_inintr(mddev);
5169 }
5170
5171 /* seq_file implementation /proc/mdstat */
5172
5173 static void status_unused(struct seq_file *seq)
5174 {
5175         int i = 0;
5176         mdk_rdev_t *rdev;
5177         struct list_head *tmp;
5178
5179         seq_printf(seq, "unused devices: ");
5180
5181         rdev_for_each_list(rdev, tmp, pending_raid_disks) {
5182                 char b[BDEVNAME_SIZE];
5183                 i++;
5184                 seq_printf(seq, "%s ",
5185                               bdevname(rdev->bdev,b));
5186         }
5187         if (!i)
5188                 seq_printf(seq, "<none>");
5189
5190         seq_printf(seq, "\n");
5191 }
5192
5193
5194 static void status_resync(struct seq_file *seq, mddev_t * mddev)
5195 {
5196         sector_t max_blocks, resync, res;
5197         unsigned long dt, db, rt;
5198         int scale;
5199         unsigned int per_milli;
5200
5201         resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active))/2;
5202
5203         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
5204                 max_blocks = mddev->resync_max_sectors >> 1;
5205         else
5206                 max_blocks = mddev->size;
5207
5208         /*
5209          * Should not happen.
5210          */
5211         if (!max_blocks) {
5212                 MD_BUG();
5213                 return;
5214         }
5215         /* Pick 'scale' such that (resync>>scale)*1000 will fit
5216          * in a sector_t, and (max_blocks>>scale) will fit in a
5217          * u32, as those are the requirements for sector_div.
5218          * Thus 'scale' must be at least 10
5219          */
5220         scale = 10;
5221         if (sizeof(sector_t) > sizeof(unsigned long)) {
5222                 while ( max_blocks/2 > (1ULL<<(scale+32)))
5223                         scale++;
5224         }
5225         res = (resync>>scale)*1000;
5226         sector_div(res, (u32)((max_blocks>>scale)+1));
5227
5228         per_milli = res;
5229         {
5230                 int i, x = per_milli/50, y = 20-x;
5231                 seq_printf(seq, "[");
5232                 for (i = 0; i < x; i++)
5233                         seq_printf(seq, "=");
5234                 seq_printf(seq, ">");
5235                 for (i = 0; i < y; i++)
5236                         seq_printf(seq, ".");
5237                 seq_printf(seq, "] ");
5238         }
5239         seq_printf(seq, " %s =%3u.%u%% (%llu/%llu)",
5240                    (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)?
5241                     "reshape" :
5242                     (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)?
5243                      "check" :
5244                      (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
5245                       "resync" : "recovery"))),
5246                    per_milli/10, per_milli % 10,
5247                    (unsigned long long) resync,
5248                    (unsigned long long) max_blocks);
5249
5250         /*
5251          * We do not want to overflow, so the order of operands and
5252          * the * 100 / 100 trick are important. We do a +1 to be
5253          * safe against division by zero. We only estimate anyway.
5254          *
5255          * dt: time from mark until now
5256          * db: blocks written from mark until now
5257          * rt: remaining time
5258          */
5259         dt = ((jiffies - mddev->resync_mark) / HZ);
5260         if (!dt) dt++;
5261         db = (mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active))
5262                 - mddev->resync_mark_cnt;
5263         rt = (dt * ((unsigned long)(max_blocks-resync) / (db/2/100+1)))/100;
5264
5265         seq_printf(seq, " finish=%lu.%lumin", rt / 60, (rt % 60)/6);
5266
5267         seq_printf(seq, " speed=%ldK/sec", db/2/dt);
5268 }
5269
5270 static void *md_seq_start(struct seq_file *seq, loff_t *pos)
5271 {
5272         struct list_head *tmp;
5273         loff_t l = *pos;
5274         mddev_t *mddev;
5275
5276         if (l >= 0x10000)
5277                 return NULL;
5278         if (!l--)
5279                 /* header */
5280                 return (void*)1;
5281
5282         spin_lock(&all_mddevs_lock);
5283         list_for_each(tmp,&all_mddevs)
5284                 if (!l--) {
5285                         mddev = list_entry(tmp, mddev_t, all_mddevs);
5286                         mddev_get(mddev);
5287                         spin_unlock(&all_mddevs_lock);
5288                         return mddev;
5289                 }
5290         spin_unlock(&all_mddevs_lock);
5291         if (!l--)
5292                 return (void*)2;/* tail */
5293         return NULL;
5294 }
5295
5296 static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
5297 {
5298         struct list_head *tmp;
5299         mddev_t *next_mddev, *mddev = v;
5300
5301         ++*pos;
5302         if (v == (void*)2)
5303                 return NULL;
5304
5305         spin_lock(&all_mddevs_lock);
5306         if (v == (void*)1)
5307                 tmp = all_mddevs.next;
5308         else
5309                 tmp = mddev->all_mddevs.next;
5310         if (tmp != &all_mddevs)
5311                 next_mddev = mddev_get(list_entry(tmp,mddev_t,all_mddevs));
5312         else {
5313                 next_mddev = (void*)2;
5314                 *pos = 0x10000;
5315         }
5316         spin_unlock(&all_mddevs_lock);
5317
5318         if (v != (void*)1)
5319                 mddev_put(mddev);
5320         return next_mddev;
5321
5322 }
5323
5324 static void md_seq_stop(struct seq_file *seq, void *v)
5325 {
5326         mddev_t *mddev = v;
5327
5328         if (mddev && v != (void*)1 && v != (void*)2)
5329                 mddev_put(mddev);
5330 }
5331
5332 struct mdstat_info {
5333         int event;
5334 };
5335
5336 static int md_seq_show(struct seq_file *seq, void *v)
5337 {
5338         mddev_t *mddev = v;
5339         sector_t size;
5340         struct list_head *tmp2;
5341         mdk_rdev_t *rdev;
5342         struct mdstat_info *mi = seq->private;
5343         struct bitmap *bitmap;
5344
5345         if (v == (void*)1) {
5346                 struct mdk_personality *pers;
5347                 seq_printf(seq, "Personalities : ");
5348                 spin_lock(&pers_lock);
5349                 list_for_each_entry(pers, &pers_list, list)
5350                         seq_printf(seq, "[%s] ", pers->name);
5351
5352                 spin_unlock(&pers_lock);
5353                 seq_printf(seq, "\n");
5354                 mi->event = atomic_read(&md_event_count);
5355                 return 0;
5356         }
5357         if (v == (void*)2) {
5358                 status_unused(seq);
5359                 return 0;
5360         }
5361
5362         if (mddev_lock(mddev) < 0)
5363                 return -EINTR;
5364
5365         if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
5366                 seq_printf(seq, "%s : %sactive", mdname(mddev),
5367                                                 mddev->pers ? "" : "in");
5368                 if (mddev->pers) {
5369                         if (mddev->ro==1)
5370                                 seq_printf(seq, " (read-only)");
5371                         if (mddev->ro==2)
5372                                 seq_printf(seq, " (auto-read-only)");
5373                         seq_printf(seq, " %s", mddev->pers->name);
5374                 }
5375
5376                 size = 0;
5377                 rdev_for_each(rdev, tmp2, mddev) {
5378                         char b[BDEVNAME_SIZE];
5379                         seq_printf(seq, " %s[%d]",
5380                                 bdevname(rdev->bdev,b), rdev->desc_nr);
5381                         if (test_bit(WriteMostly, &rdev->flags))
5382                                 seq_printf(seq, "(W)");
5383                         if (test_bit(Faulty, &rdev->flags)) {
5384                                 seq_printf(seq, "(F)");
5385                                 continue;
5386                         } else if (rdev->raid_disk < 0)
5387                                 seq_printf(seq, "(S)"); /* spare */
5388                         size += rdev->size;
5389                 }
5390
5391                 if (!list_empty(&mddev->disks)) {
5392                         if (mddev->pers)
5393                                 seq_printf(seq, "\n      %llu blocks",
5394                                         (unsigned long long)mddev->array_size);
5395                         else
5396                                 seq_printf(seq, "\n      %llu blocks",
5397                                         (unsigned long long)size);
5398                 }
5399                 if (mddev->persistent) {
5400                         if (mddev->major_version != 0 ||
5401                             mddev->minor_version != 90) {
5402                                 seq_printf(seq," super %d.%d",
5403                                            mddev->major_version,
5404                                            mddev->minor_version);
5405                         }
5406                 } else if (mddev->external)
5407                         seq_printf(seq, " super external:%s",
5408                                    mddev->metadata_type);
5409                 else
5410                         seq_printf(seq, " super non-persistent");
5411
5412                 if (mddev->pers) {
5413                         mddev->pers->status (seq, mddev);
5414                         seq_printf(seq, "\n      ");
5415                         if (mddev->pers->sync_request) {
5416                                 if (mddev->curr_resync > 2) {
5417                                         status_resync (seq, mddev);
5418                                         seq_printf(seq, "\n      ");
5419                                 } else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
5420                                         seq_printf(seq, "\tresync=DELAYED\n      ");
5421                                 else if (mddev->recovery_cp < MaxSector)
5422                                         seq_printf(seq, "\tresync=PENDING\n      ");
5423                         }
5424                 } else
5425                         seq_printf(seq, "\n       ");
5426
5427                 if ((bitmap = mddev->bitmap)) {
5428                         unsigned long chunk_kb;
5429                         unsigned long flags;
5430                         spin_lock_irqsave(&bitmap->lock, flags);
5431                         chunk_kb = bitmap->chunksize >> 10;
5432                         seq_printf(seq, "bitmap: %lu/%lu pages [%luKB], "
5433                                 "%lu%s chunk",
5434                                 bitmap->pages - bitmap->missing_pages,
5435                                 bitmap->pages,
5436                                 (bitmap->pages - bitmap->missing_pages)
5437                                         << (PAGE_SHIFT - 10),
5438                                 chunk_kb ? chunk_kb : bitmap->chunksize,
5439                                 chunk_kb ? "KB" : "B");
5440                         if (bitmap->file) {
5441                                 seq_printf(seq, ", file: ");
5442                                 seq_path(seq, &bitmap->file->f_path, " \t\n");
5443                         }
5444
5445                         seq_printf(seq, "\n");
5446                         spin_unlock_irqrestore(&bitmap->lock, flags);
5447                 }
5448
5449                 seq_printf(seq, "\n");
5450         }
5451         mddev_unlock(mddev);
5452
5453         return 0;
5454 }
5455
5456 static struct seq_operations md_seq_ops = {
5457         .start  = md_seq_start,
5458         .next   = md_seq_next,
5459         .stop   = md_seq_stop,
5460         .show   = md_seq_show,
5461 };
5462
5463 static int md_seq_open(struct inode *inode, struct file *file)
5464 {
5465         int error;
5466         struct mdstat_info *mi = kmalloc(sizeof(*mi), GFP_KERNEL);
5467         if (mi == NULL)
5468                 return -ENOMEM;
5469
5470         error = seq_open(file, &md_seq_ops);
5471         if (error)
5472                 kfree(mi);
5473         else {
5474                 struct seq_file *p = file->private_data;
5475                 p->private = mi;
5476                 mi->event = atomic_read(&md_event_count);
5477         }
5478         return error;
5479 }
5480
5481 static unsigned int mdstat_poll(struct file *filp, poll_table *wait)
5482 {
5483         struct seq_file *m = filp->private_data;
5484         struct mdstat_info *mi = m->private;
5485         int mask;
5486
5487         poll_wait(filp, &md_event_waiters, wait);
5488
5489         /* always allow read */
5490         mask = POLLIN | POLLRDNORM;
5491
5492         if (mi->event != atomic_read(&md_event_count))
5493                 mask |= POLLERR | POLLPRI;
5494         return mask;
5495 }
5496
5497 static const struct file_operations md_seq_fops = {
5498         .owner          = THIS_MODULE,
5499         .open           = md_seq_open,
5500         .read           = seq_read,
5501         .llseek         = seq_lseek,
5502         .release        = seq_release_private,
5503         .poll           = mdstat_poll,
5504 };
5505
5506 int register_md_personality(struct mdk_personality *p)
5507 {
5508         spin_lock(&pers_lock);
5509         list_add_tail(&p->list, &pers_list);
5510         printk(KERN_INFO "md: %s personality registered for level %d\n", p->name, p->level);
5511         spin_unlock(&pers_lock);
5512         return 0;
5513 }
5514
5515 int unregister_md_personality(struct mdk_personality *p)
5516 {
5517         printk(KERN_INFO "md: %s personality unregistered\n", p->name);
5518         spin_lock(&pers_lock);
5519         list_del_init(&p->list);
5520         spin_unlock(&pers_lock);
5521         return 0;
5522 }
5523
5524 static int is_mddev_idle(mddev_t *mddev)
5525 {
5526         mdk_rdev_t * rdev;
5527         struct list_head *tmp;
5528         int idle;
5529         long curr_events;
5530
5531         idle = 1;
5532         rdev_for_each(rdev, tmp, mddev) {
5533                 struct gendisk *disk = rdev->bdev->bd_contains->bd_disk;
5534                 curr_events = disk_stat_read(disk, sectors[0]) +
5535                                 disk_stat_read(disk, sectors[1]) -
5536                                 atomic_read(&disk->sync_io);
5537                 /* sync IO will cause sync_io to increase before the disk_stats
5538                  * as sync_io is counted when a request starts, and
5539                  * disk_stats is counted when it completes.
5540                  * So resync activity will cause curr_events to be smaller than
5541                  * when there was no such activity.
5542                  * non-sync IO will cause disk_stat to increase without
5543                  * increasing sync_io so curr_events will (eventually)
5544                  * be larger than it was before.  Once it becomes
5545                  * substantially larger, the test below will cause
5546                  * the array to appear non-idle, and resync will slow
5547                  * down.
5548                  * If there is a lot of outstanding resync activity when
5549                  * we set last_event to curr_events, then all that activity
5550                  * completing might cause the array to appear non-idle
5551                  * and resync will be slowed down even though there might
5552                  * not have been non-resync activity.  This will only
5553                  * happen once though.  'last_events' will soon reflect
5554                  * the state where there is little or no outstanding
5555                  * resync requests, and further resync activity will
5556                  * always make curr_events less than last_events.
5557                  *
5558                  */
5559                 if (curr_events - rdev->last_events > 4096) {
5560                         rdev->last_events = curr_events;
5561                         idle = 0;
5562                 }
5563         }
5564         return idle;
5565 }
5566
5567 void md_done_sync(mddev_t *mddev, int blocks, int ok)
5568 {
5569         /* another "blocks" (512byte) blocks have been synced */
5570         atomic_sub(blocks, &mddev->recovery_active);
5571         wake_up(&mddev->recovery_wait);
5572         if (!ok) {
5573                 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
5574                 md_wakeup_thread(mddev->thread);
5575                 // stop recovery, signal do_sync ....
5576         }
5577 }
5578
5579
5580 /* md_write_start(mddev, bi)
5581  * If we need to update some array metadata (e.g. 'active' flag
5582  * in superblock) before writing, schedule a superblock update
5583  * and wait for it to complete.
5584  */
5585 void md_write_start(mddev_t *mddev, struct bio *bi)
5586 {
5587         int did_change = 0;
5588         if (bio_data_dir(bi) != WRITE)
5589                 return;
5590
5591         BUG_ON(mddev->ro == 1);
5592         if (mddev->ro == 2) {
5593                 /* need to switch to read/write */
5594                 mddev->ro = 0;
5595                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5596                 md_wakeup_thread(mddev->thread);
5597                 md_wakeup_thread(mddev->sync_thread);
5598                 did_change = 1;
5599         }
5600         atomic_inc(&mddev->writes_pending);
5601         if (mddev->safemode == 1)
5602                 mddev->safemode = 0;
5603         if (mddev->in_sync) {
5604                 spin_lock_irq(&mddev->write_lock);
5605                 if (mddev->in_sync) {
5606                         mddev->in_sync = 0;
5607                         set_bit(MD_CHANGE_CLEAN, &mddev->flags);
5608                         md_wakeup_thread(mddev->thread);
5609                         did_change = 1;
5610                 }
5611                 spin_unlock_irq(&mddev->write_lock);
5612         }
5613         if (did_change)
5614                 sysfs_notify(&mddev->kobj, NULL, "array_state");
5615         wait_event(mddev->sb_wait,
5616                    !test_bit(MD_CHANGE_CLEAN, &mddev->flags) &&
5617                    !test_bit(MD_CHANGE_PENDING, &mddev->flags));
5618 }
5619
5620 void md_write_end(mddev_t *mddev)
5621 {
5622         if (atomic_dec_and_test(&mddev->writes_pending)) {
5623                 if (mddev->safemode == 2)
5624                         md_wakeup_thread(mddev->thread);
5625                 else if (mddev->safemode_delay)
5626                         mod_timer(&mddev->safemode_timer, jiffies + mddev->safemode_delay);
5627         }
5628 }
5629
5630 /* md_allow_write(mddev)
5631  * Calling this ensures that the array is marked 'active' so that writes
5632  * may proceed without blocking.  It is important to call this before
5633  * attempting a GFP_KERNEL allocation while holding the mddev lock.
5634  * Must be called with mddev_lock held.
5635  *
5636  * In the ->external case MD_CHANGE_CLEAN can not be cleared until mddev->lock
5637  * is dropped, so return -EAGAIN after notifying userspace.
5638  */
5639 int md_allow_write(mddev_t *mddev)
5640 {
5641         if (!mddev->pers)
5642                 return 0;
5643         if (mddev->ro)
5644                 return 0;
5645         if (!mddev->pers->sync_request)
5646                 return 0;
5647
5648         spin_lock_irq(&mddev->write_lock);
5649         if (mddev->in_sync) {
5650                 mddev->in_sync = 0;
5651                 set_bit(MD_CHANGE_CLEAN, &mddev->flags);
5652                 if (mddev->safemode_delay &&
5653                     mddev->safemode == 0)
5654                         mddev->safemode = 1;
5655                 spin_unlock_irq(&mddev->write_lock);
5656                 md_update_sb(mddev, 0);
5657                 sysfs_notify(&mddev->kobj, NULL, "array_state");
5658         } else
5659                 spin_unlock_irq(&mddev->write_lock);
5660
5661         if (test_bit(MD_CHANGE_CLEAN, &mddev->flags))
5662                 return -EAGAIN;
5663         else
5664                 return 0;
5665 }
5666 EXPORT_SYMBOL_GPL(md_allow_write);
5667
5668 #define SYNC_MARKS      10
5669 #define SYNC_MARK_STEP  (3*HZ)
5670 void md_do_sync(mddev_t *mddev)
5671 {
5672         mddev_t *mddev2;
5673         unsigned int currspeed = 0,
5674                  window;
5675         sector_t max_sectors,j, io_sectors;
5676         unsigned long mark[SYNC_MARKS];
5677         sector_t mark_cnt[SYNC_MARKS];
5678         int last_mark,m;
5679         struct list_head *tmp;
5680         sector_t last_check;
5681         int skipped = 0;
5682         struct list_head *rtmp;
5683         mdk_rdev_t *rdev;
5684         char *desc;
5685
5686         /* just incase thread restarts... */
5687         if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
5688                 return;
5689         if (mddev->ro) /* never try to sync a read-only array */
5690                 return;
5691
5692         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
5693                 if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
5694                         desc = "data-check";
5695                 else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
5696                         desc = "requested-resync";
5697                 else
5698                         desc = "resync";
5699         } else if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
5700                 desc = "reshape";
5701         else
5702                 desc = "recovery";
5703
5704         /* we overload curr_resync somewhat here.
5705          * 0 == not engaged in resync at all
5706          * 2 == checking that there is no conflict with another sync
5707          * 1 == like 2, but have yielded to allow conflicting resync to
5708          *              commense
5709          * other == active in resync - this many blocks
5710          *
5711          * Before starting a resync we must have set curr_resync to
5712          * 2, and then checked that every "conflicting" array has curr_resync
5713          * less than ours.  When we find one that is the same or higher
5714          * we wait on resync_wait.  To avoid deadlock, we reduce curr_resync
5715          * to 1 if we choose to yield (based arbitrarily on address of mddev structure).
5716          * This will mean we have to start checking from the beginning again.
5717          *
5718          */
5719
5720         do {
5721                 mddev->curr_resync = 2;
5722
5723         try_again:
5724                 if (kthread_should_stop()) {
5725                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
5726                         goto skip;
5727                 }
5728                 for_each_mddev(mddev2, tmp) {
5729                         if (mddev2 == mddev)
5730                                 continue;
5731                         if (!mddev->parallel_resync
5732                         &&  mddev2->curr_resync
5733                         &&  match_mddev_units(mddev, mddev2)) {
5734                                 DEFINE_WAIT(wq);
5735                                 if (mddev < mddev2 && mddev->curr_resync == 2) {
5736                                         /* arbitrarily yield */
5737                                         mddev->curr_resync = 1;
5738                                         wake_up(&resync_wait);
5739                                 }
5740                                 if (mddev > mddev2 && mddev->curr_resync == 1)
5741                                         /* no need to wait here, we can wait the next
5742                                          * time 'round when curr_resync == 2
5743                                          */
5744                                         continue;
5745                                 prepare_to_wait(&resync_wait, &wq, TASK_UNINTERRUPTIBLE);
5746                                 if (!kthread_should_stop() &&
5747                                     mddev2->curr_resync >= mddev->curr_resync) {
5748                                         printk(KERN_INFO "md: delaying %s of %s"
5749                                                " until %s has finished (they"
5750                                                " share one or more physical units)\n",
5751                                                desc, mdname(mddev), mdname(mddev2));
5752                                         mddev_put(mddev2);
5753                                         schedule();
5754                                         finish_wait(&resync_wait, &wq);
5755                                         goto try_again;
5756                                 }
5757                                 finish_wait(&resync_wait, &wq);
5758                         }
5759                 }
5760         } while (mddev->curr_resync < 2);
5761
5762         j = 0;
5763         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
5764                 /* resync follows the size requested by the personality,
5765                  * which defaults to physical size, but can be virtual size
5766                  */
5767                 max_sectors = mddev->resync_max_sectors;
5768                 mddev->resync_mismatches = 0;
5769                 /* we don't use the checkpoint if there's a bitmap */
5770                 if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
5771                         j = mddev->resync_min;
5772                 else if (!mddev->bitmap)
5773                         j = mddev->recovery_cp;
5774
5775         } else if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
5776                 max_sectors = mddev->size << 1;
5777         else {
5778                 /* recovery follows the physical size of devices */
5779                 max_sectors = mddev->size << 1;
5780                 j = MaxSector;
5781                 rdev_for_each(rdev, rtmp, mddev)
5782                         if (rdev->raid_disk >= 0 &&
5783                             !test_bit(Faulty, &rdev->flags) &&
5784                             !test_bit(In_sync, &rdev->flags) &&
5785                             rdev->recovery_offset < j)
5786                                 j = rdev->recovery_offset;
5787         }
5788
5789         printk(KERN_INFO "md: %s of RAID array %s\n", desc, mdname(mddev));
5790         printk(KERN_INFO "md: minimum _guaranteed_  speed:"
5791                 " %d KB/sec/disk.\n", speed_min(mddev));
5792         printk(KERN_INFO "md: using maximum available idle IO bandwidth "
5793                "(but not more than %d KB/sec) for %s.\n",
5794                speed_max(mddev), desc);
5795
5796         is_mddev_idle(mddev); /* this also initializes IO event counters */
5797
5798         io_sectors = 0;
5799         for (m = 0; m < SYNC_MARKS; m++) {
5800                 mark[m] = jiffies;
5801                 mark_cnt[m] = io_sectors;
5802         }
5803         last_mark = 0;
5804         mddev->resync_mark = mark[last_mark];
5805         mddev->resync_mark_cnt = mark_cnt[last_mark];
5806
5807         /*
5808          * Tune reconstruction:
5809          */
5810         window = 32*(PAGE_SIZE/512);
5811         printk(KERN_INFO "md: using %dk window, over a total of %llu blocks.\n",
5812                 window/2,(unsigned long long) max_sectors/2);
5813
5814         atomic_set(&mddev->recovery_active, 0);
5815         last_check = 0;
5816
5817         if (j>2) {
5818                 printk(KERN_INFO
5819                        "md: resuming %s of %s from checkpoint.\n",
5820                        desc, mdname(mddev));
5821                 mddev->curr_resync = j;
5822         }
5823
5824         while (j < max_sectors) {
5825                 sector_t sectors;
5826
5827                 skipped = 0;
5828                 if (j >= mddev->resync_max) {
5829                         sysfs_notify(&mddev->kobj, NULL, "sync_completed");
5830                         wait_event(mddev->recovery_wait,
5831                                    mddev->resync_max > j
5832                                    || kthread_should_stop());
5833                 }
5834                 if (kthread_should_stop())
5835                         goto interrupted;
5836                 sectors = mddev->pers->sync_request(mddev, j, &skipped,
5837                                                   currspeed < speed_min(mddev));
5838                 if (sectors == 0) {
5839                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
5840                         goto out;
5841                 }
5842
5843                 if (!skipped) { /* actual IO requested */
5844                         io_sectors += sectors;
5845                         atomic_add(sectors, &mddev->recovery_active);
5846                 }
5847
5848                 j += sectors;
5849                 if (j>1) mddev->curr_resync = j;
5850                 mddev->curr_mark_cnt = io_sectors;
5851                 if (last_check == 0)
5852                         /* this is the earliers that rebuilt will be
5853                          * visible in /proc/mdstat
5854                          */
5855                         md_new_event(mddev);
5856
5857                 if (last_check + window > io_sectors || j == max_sectors)
5858                         continue;
5859
5860                 last_check = io_sectors;
5861
5862                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
5863                         break;
5864
5865         repeat:
5866                 if (time_after_eq(jiffies, mark[last_mark] + SYNC_MARK_STEP )) {
5867                         /* step marks */
5868                         int next = (last_mark+1) % SYNC_MARKS;
5869
5870                         mddev->resync_mark = mark[next];
5871                         mddev->resync_mark_cnt = mark_cnt[next];
5872                         mark[next] = jiffies;
5873                         mark_cnt[next] = io_sectors - atomic_read(&mddev->recovery_active);
5874                         last_mark = next;
5875                 }
5876
5877
5878                 if (kthread_should_stop())
5879                         goto interrupted;
5880
5881
5882                 /*
5883                  * this loop exits only if either when we are slower than
5884                  * the 'hard' speed limit, or the system was IO-idle for
5885                  * a jiffy.
5886                  * the system might be non-idle CPU-wise, but we only care
5887                  * about not overloading the IO subsystem. (things like an
5888                  * e2fsck being done on the RAID array should execute fast)
5889                  */
5890                 blk_unplug(mddev->queue);
5891                 cond_resched();
5892
5893                 currspeed = ((unsigned long)(io_sectors-mddev->resync_mark_cnt))/2
5894                         /((jiffies-mddev->resync_mark)/HZ +1) +1;
5895
5896                 if (currspeed > speed_min(mddev)) {
5897                         if ((currspeed > speed_max(mddev)) ||
5898                                         !is_mddev_idle(mddev)) {
5899                                 msleep(500);
5900                                 goto repeat;
5901                         }
5902                 }
5903         }
5904         printk(KERN_INFO "md: %s: %s done.\n",mdname(mddev), desc);
5905         /*
5906          * this also signals 'finished resyncing' to md_stop
5907          */
5908  out:
5909         blk_unplug(mddev->queue);
5910
5911         wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
5912
5913         /* tell personality that we are finished */
5914         mddev->pers->sync_request(mddev, max_sectors, &skipped, 1);
5915
5916         if (!test_bit(MD_RECOVERY_CHECK, &mddev->recovery) &&
5917             mddev->curr_resync > 2) {
5918                 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
5919                         if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
5920                                 if (mddev->curr_resync >= mddev->recovery_cp) {
5921                                         printk(KERN_INFO
5922                                                "md: checkpointing %s of %s.\n",
5923                                                desc, mdname(mddev));
5924                                         mddev->recovery_cp = mddev->curr_resync;
5925                                 }
5926                         } else
5927                                 mddev->recovery_cp = MaxSector;
5928                 } else {
5929                         if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery))
5930                                 mddev->curr_resync = MaxSector;
5931                         rdev_for_each(rdev, rtmp, mddev)
5932                                 if (rdev->raid_disk >= 0 &&
5933                                     !test_bit(Faulty, &rdev->flags) &&
5934                                     !test_bit(In_sync, &rdev->flags) &&
5935                                     rdev->recovery_offset < mddev->curr_resync)
5936                                         rdev->recovery_offset = mddev->curr_resync;
5937                 }
5938         }
5939         set_bit(MD_CHANGE_DEVS, &mddev->flags);
5940
5941  skip:
5942         mddev->curr_resync = 0;
5943         mddev->resync_min = 0;
5944         mddev->resync_max = MaxSector;
5945         sysfs_notify(&mddev->kobj, NULL, "sync_completed");
5946         wake_up(&resync_wait);
5947         set_bit(MD_RECOVERY_DONE, &mddev->recovery);
5948         md_wakeup_thread(mddev->thread);
5949         return;
5950
5951  interrupted:
5952         /*
5953          * got a signal, exit.
5954          */
5955         printk(KERN_INFO
5956                "md: md_do_sync() got signal ... exiting\n");
5957         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
5958         goto out;
5959
5960 }
5961 EXPORT_SYMBOL_GPL(md_do_sync);
5962
5963
5964 static int remove_and_add_spares(mddev_t *mddev)
5965 {
5966         mdk_rdev_t *rdev;
5967         struct list_head *rtmp;
5968         int spares = 0;
5969
5970         rdev_for_each(rdev, rtmp, mddev)
5971                 if (rdev->raid_disk >= 0 &&
5972                     !test_bit(Blocked, &rdev->flags) &&
5973                     (test_bit(Faulty, &rdev->flags) ||
5974                      ! test_bit(In_sync, &rdev->flags)) &&
5975                     atomic_read(&rdev->nr_pending)==0) {
5976                         if (mddev->pers->hot_remove_disk(
5977                                     mddev, rdev->raid_disk)==0) {
5978                                 char nm[20];
5979                                 sprintf(nm,"rd%d", rdev->raid_disk);
5980                                 sysfs_remove_link(&mddev->kobj, nm);
5981                                 rdev->raid_disk = -1;
5982                         }
5983                 }
5984
5985         if (mddev->degraded) {
5986                 rdev_for_each(rdev, rtmp, mddev) {
5987                         if (rdev->raid_disk >= 0 &&
5988                             !test_bit(In_sync, &rdev->flags))
5989                                 spares++;
5990                         if (rdev->raid_disk < 0
5991                             && !test_bit(Faulty, &rdev->flags)) {
5992                                 rdev->recovery_offset = 0;
5993                                 if (mddev->pers->
5994                                     hot_add_disk(mddev, rdev) == 0) {
5995                                         char nm[20];
5996                                         sprintf(nm, "rd%d", rdev->raid_disk);
5997                                         if (sysfs_create_link(&mddev->kobj,
5998                                                               &rdev->kobj, nm))
5999                                                 printk(KERN_WARNING
6000                                                        "md: cannot register "
6001                                                        "%s for %s\n",
6002                                                        nm, mdname(mddev));
6003                                         spares++;
6004                                         md_new_event(mddev);
6005                                 } else
6006                                         break;
6007                         }
6008                 }
6009         }
6010         return spares;
6011 }
6012 /*
6013  * This routine is regularly called by all per-raid-array threads to
6014  * deal with generic issues like resync and super-block update.
6015  * Raid personalities that don't have a thread (linear/raid0) do not
6016  * need this as they never do any recovery or update the superblock.
6017  *
6018  * It does not do any resync itself, but rather "forks" off other threads
6019  * to do that as needed.
6020  * When it is determined that resync is needed, we set MD_RECOVERY_RUNNING in
6021  * "->recovery" and create a thread at ->sync_thread.
6022  * When the thread finishes it sets MD_RECOVERY_DONE
6023  * and wakeups up this thread which will reap the thread and finish up.
6024  * This thread also removes any faulty devices (with nr_pending == 0).
6025  *
6026  * The overall approach is:
6027  *  1/ if the superblock needs updating, update it.
6028  *  2/ If a recovery thread is running, don't do anything else.
6029  *  3/ If recovery has finished, clean up, possibly marking spares active.
6030  *  4/ If there are any faulty devices, remove them.
6031  *  5/ If array is degraded, try to add spares devices
6032  *  6/ If array has spares or is not in-sync, start a resync thread.
6033  */
6034 void md_check_recovery(mddev_t *mddev)
6035 {
6036         mdk_rdev_t *rdev;
6037         struct list_head *rtmp;
6038
6039
6040         if (mddev->bitmap)
6041                 bitmap_daemon_work(mddev->bitmap);
6042
6043         if (mddev->ro)
6044                 return;
6045
6046         if (signal_pending(current)) {
6047                 if (mddev->pers->sync_request && !mddev->external) {
6048                         printk(KERN_INFO "md: %s in immediate safe mode\n",
6049                                mdname(mddev));
6050                         mddev->safemode = 2;
6051                 }
6052                 flush_signals(current);
6053         }
6054
6055         if ( ! (
6056                 (mddev->flags && !mddev->external) ||
6057                 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
6058                 test_bit(MD_RECOVERY_DONE, &mddev->recovery) ||
6059                 (mddev->external == 0 && mddev->safemode == 1) ||
6060                 (mddev->safemode == 2 && ! atomic_read(&mddev->writes_pending)
6061                  && !mddev->in_sync && mddev->recovery_cp == MaxSector)
6062                 ))
6063                 return;
6064
6065         if (mddev_trylock(mddev)) {
6066                 int spares = 0;
6067
6068                 if (!mddev->external) {
6069                         int did_change = 0;
6070                         spin_lock_irq(&mddev->write_lock);
6071                         if (mddev->safemode &&
6072                             !atomic_read(&mddev->writes_pending) &&
6073                             !mddev->in_sync &&
6074                             mddev->recovery_cp == MaxSector) {
6075                                 mddev->in_sync = 1;
6076                                 did_change = 1;
6077                                 if (mddev->persistent)
6078                                         set_bit(MD_CHANGE_CLEAN, &mddev->flags);
6079                         }
6080                         if (mddev->safemode == 1)
6081                                 mddev->safemode = 0;
6082                         spin_unlock_irq(&mddev->write_lock);
6083                         if (did_change)
6084                                 sysfs_notify(&mddev->kobj, NULL, "array_state");
6085                 }
6086
6087                 if (mddev->flags)
6088                         md_update_sb(mddev, 0);
6089
6090                 rdev_for_each(rdev, rtmp, mddev)
6091                         if (test_and_clear_bit(StateChanged, &rdev->flags))
6092                                 sysfs_notify(&rdev->kobj, NULL, "state");
6093
6094
6095                 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
6096                     !test_bit(MD_RECOVERY_DONE, &mddev->recovery)) {
6097                         /* resync/recovery still happening */
6098                         clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6099                         goto unlock;
6100                 }
6101                 if (mddev->sync_thread) {
6102                         /* resync has finished, collect result */
6103                         md_unregister_thread(mddev->sync_thread);
6104                         mddev->sync_thread = NULL;
6105                         if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
6106                                 /* success...*/
6107                                 /* activate any spares */
6108                                 if (mddev->pers->spare_active(mddev))
6109                                         sysfs_notify(&mddev->kobj, NULL,
6110                                                      "degraded");
6111                         }
6112                         md_update_sb(mddev, 1);
6113
6114                         /* if array is no-longer degraded, then any saved_raid_disk
6115                          * information must be scrapped
6116                          */
6117                         if (!mddev->degraded)
6118                                 rdev_for_each(rdev, rtmp, mddev)
6119                                         rdev->saved_raid_disk = -1;
6120
6121                         mddev->recovery = 0;
6122                         /* flag recovery needed just to double check */
6123                         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6124                         sysfs_notify(&mddev->kobj, NULL, "sync_action");
6125                         md_new_event(mddev);
6126                         goto unlock;
6127                 }
6128                 /* Set RUNNING before clearing NEEDED to avoid
6129                  * any transients in the value of "sync_action".
6130                  */
6131                 set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
6132                 clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6133                 /* Clear some bits that don't mean anything, but
6134                  * might be left set
6135                  */
6136                 clear_bit(MD_RECOVERY_INTR, &mddev->recovery);
6137                 clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
6138
6139                 if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
6140                         goto unlock;
6141                 /* no recovery is running.
6142                  * remove any failed drives, then
6143                  * add spares if possible.
6144                  * Spare are also removed and re-added, to allow
6145                  * the personality to fail the re-add.
6146                  */
6147
6148                 if (mddev->reshape_position != MaxSector) {
6149                         if (mddev->pers->check_reshape(mddev) != 0)
6150                                 /* Cannot proceed */
6151                                 goto unlock;
6152                         set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
6153                         clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
6154                 } else if ((spares = remove_and_add_spares(mddev))) {
6155                         clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
6156                         clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
6157                         set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
6158                 } else if (mddev->recovery_cp < MaxSector) {
6159                         set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
6160                         clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
6161                 } else if (!test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
6162                         /* nothing to be done ... */
6163                         goto unlock;
6164
6165                 if (mddev->pers->sync_request) {
6166                         if (spares && mddev->bitmap && ! mddev->bitmap->file) {
6167                                 /* We are adding a device or devices to an array
6168                                  * which has the bitmap stored on all devices.
6169                                  * So make sure all bitmap pages get written
6170                                  */
6171                                 bitmap_write_all(mddev->bitmap);
6172                         }
6173                         mddev->sync_thread = md_register_thread(md_do_sync,
6174                                                                 mddev,
6175                                                                 "%s_resync");
6176                         if (!mddev->sync_thread) {
6177                                 printk(KERN_ERR "%s: could not start resync"
6178                                         " thread...\n",
6179                                         mdname(mddev));
6180                                 /* leave the spares where they are, it shouldn't hurt */
6181                                 mddev->recovery = 0;
6182                         } else
6183                                 md_wakeup_thread(mddev->sync_thread);
6184                         sysfs_notify(&mddev->kobj, NULL, "sync_action");
6185                         md_new_event(mddev);
6186                 }
6187         unlock:
6188                 if (!mddev->sync_thread) {
6189                         clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
6190                         if (test_and_clear_bit(MD_RECOVERY_RECOVER,
6191                                                &mddev->recovery))
6192                                 sysfs_notify(&mddev->kobj, NULL, "sync_action");
6193                 }
6194                 mddev_unlock(mddev);
6195         }
6196 }
6197
6198 void md_wait_for_blocked_rdev(mdk_rdev_t *rdev, mddev_t *mddev)
6199 {
6200         sysfs_notify(&rdev->kobj, NULL, "state");
6201         wait_event_timeout(rdev->blocked_wait,
6202                            !test_bit(Blocked, &rdev->flags),
6203                            msecs_to_jiffies(5000));
6204         rdev_dec_pending(rdev, mddev);
6205 }
6206 EXPORT_SYMBOL(md_wait_for_blocked_rdev);
6207
6208 static int md_notify_reboot(struct notifier_block *this,
6209                             unsigned long code, void *x)
6210 {
6211         struct list_head *tmp;
6212         mddev_t *mddev;
6213
6214         if ((code == SYS_DOWN) || (code == SYS_HALT) || (code == SYS_POWER_OFF)) {
6215
6216                 printk(KERN_INFO "md: stopping all md devices.\n");
6217
6218                 for_each_mddev(mddev, tmp)
6219                         if (mddev_trylock(mddev)) {
6220                                 do_md_stop (mddev, 1, 0);
6221                                 mddev_unlock(mddev);
6222                         }
6223                 /*
6224                  * certain more exotic SCSI devices are known to be
6225                  * volatile wrt too early system reboots. While the
6226                  * right place to handle this issue is the given
6227                  * driver, we do want to have a safe RAID driver ...
6228                  */
6229                 mdelay(1000*1);
6230         }
6231         return NOTIFY_DONE;
6232 }
6233
6234 static struct notifier_block md_notifier = {
6235         .notifier_call  = md_notify_reboot,
6236         .next           = NULL,
6237         .priority       = INT_MAX, /* before any real devices */
6238 };
6239
6240 static void md_geninit(void)
6241 {
6242         dprintk("md: sizeof(mdp_super_t) = %d\n", (int)sizeof(mdp_super_t));
6243
6244         proc_create("mdstat", S_IRUGO, NULL, &md_seq_fops);
6245 }
6246
6247 static int __init md_init(void)
6248 {
6249         if (register_blkdev(MAJOR_NR, "md"))
6250                 return -1;
6251         if ((mdp_major=register_blkdev(0, "mdp"))<=0) {
6252                 unregister_blkdev(MAJOR_NR, "md");
6253                 return -1;
6254         }
6255         blk_register_region(MKDEV(MAJOR_NR, 0), 1UL<<MINORBITS, THIS_MODULE,
6256                             md_probe, NULL, NULL);
6257         blk_register_region(MKDEV(mdp_major, 0), 1UL<<MINORBITS, THIS_MODULE,
6258                             md_probe, NULL, NULL);
6259
6260         register_reboot_notifier(&md_notifier);
6261         raid_table_header = register_sysctl_table(raid_root_table);
6262
6263         md_geninit();
6264         return (0);
6265 }
6266
6267
6268 #ifndef MODULE
6269
6270 /*
6271  * Searches all registered partitions for autorun RAID arrays
6272  * at boot time.
6273  */
6274
6275 static LIST_HEAD(all_detected_devices);
6276 struct detected_devices_node {
6277         struct list_head list;
6278         dev_t dev;
6279 };
6280
6281 void md_autodetect_dev(dev_t dev)
6282 {
6283         struct detected_devices_node *node_detected_dev;
6284
6285         node_detected_dev = kzalloc(sizeof(*node_detected_dev), GFP_KERNEL);
6286         if (node_detected_dev) {
6287                 node_detected_dev->dev = dev;
6288                 list_add_tail(&node_detected_dev->list, &all_detected_devices);
6289         } else {
6290                 printk(KERN_CRIT "md: md_autodetect_dev: kzalloc failed"
6291                         ", skipping dev(%d,%d)\n", MAJOR(dev), MINOR(dev));
6292         }
6293 }
6294
6295
6296 static void autostart_arrays(int part)
6297 {
6298         mdk_rdev_t *rdev;
6299         struct detected_devices_node *node_detected_dev;
6300         dev_t dev;
6301         int i_scanned, i_passed;
6302
6303         i_scanned = 0;
6304         i_passed = 0;
6305
6306         printk(KERN_INFO "md: Autodetecting RAID arrays.\n");
6307
6308         while (!list_empty(&all_detected_devices) && i_scanned < INT_MAX) {
6309                 i_scanned++;
6310                 node_detected_dev = list_entry(all_detected_devices.next,
6311                                         struct detected_devices_node, list);
6312                 list_del(&node_detected_dev->list);
6313                 dev = node_detected_dev->dev;
6314                 kfree(node_detected_dev);
6315                 rdev = md_import_device(dev,0, 90);
6316                 if (IS_ERR(rdev))
6317                         continue;
6318
6319                 if (test_bit(Faulty, &rdev->flags)) {
6320                         MD_BUG();
6321                         continue;
6322                 }
6323                 set_bit(AutoDetected, &rdev->flags);
6324                 list_add(&rdev->same_set, &pending_raid_disks);
6325                 i_passed++;
6326         }
6327
6328         printk(KERN_INFO "md: Scanned %d and added %d devices.\n",
6329                                                 i_scanned, i_passed);
6330
6331         autorun_devices(part);
6332 }
6333
6334 #endif /* !MODULE */
6335
6336 static __exit void md_exit(void)
6337 {
6338         mddev_t *mddev;
6339         struct list_head *tmp;
6340
6341         blk_unregister_region(MKDEV(MAJOR_NR,0), 1U << MINORBITS);
6342         blk_unregister_region(MKDEV(mdp_major,0), 1U << MINORBITS);
6343
6344         unregister_blkdev(MAJOR_NR,"md");
6345         unregister_blkdev(mdp_major, "mdp");
6346         unregister_reboot_notifier(&md_notifier);
6347         unregister_sysctl_table(raid_table_header);
6348         remove_proc_entry("mdstat", NULL);
6349         for_each_mddev(mddev, tmp) {
6350                 struct gendisk *disk = mddev->gendisk;
6351                 if (!disk)
6352                         continue;
6353                 export_array(mddev);
6354                 del_gendisk(disk);
6355                 put_disk(disk);
6356                 mddev->gendisk = NULL;
6357                 mddev_put(mddev);
6358         }
6359 }
6360
6361 subsys_initcall(md_init);
6362 module_exit(md_exit)
6363
6364 static int get_ro(char *buffer, struct kernel_param *kp)
6365 {
6366         return sprintf(buffer, "%d", start_readonly);
6367 }
6368 static int set_ro(const char *val, struct kernel_param *kp)
6369 {
6370         char *e;
6371         int num = simple_strtoul(val, &e, 10);
6372         if (*val && (*e == '\0' || *e == '\n')) {
6373                 start_readonly = num;
6374                 return 0;
6375         }
6376         return -EINVAL;
6377 }
6378
6379 module_param_call(start_ro, set_ro, get_ro, NULL, S_IRUSR|S_IWUSR);
6380 module_param(start_dirty_degraded, int, S_IRUGO|S_IWUSR);
6381
6382
6383 EXPORT_SYMBOL(register_md_personality);
6384 EXPORT_SYMBOL(unregister_md_personality);
6385 EXPORT_SYMBOL(md_error);
6386 EXPORT_SYMBOL(md_done_sync);
6387 EXPORT_SYMBOL(md_write_start);
6388 EXPORT_SYMBOL(md_write_end);
6389 EXPORT_SYMBOL(md_register_thread);
6390 EXPORT_SYMBOL(md_unregister_thread);
6391 EXPORT_SYMBOL(md_wakeup_thread);
6392 EXPORT_SYMBOL(md_check_recovery);
6393 MODULE_LICENSE("GPL");
6394 MODULE_ALIAS("md");
6395 MODULE_ALIAS_BLOCKDEV_MAJOR(MD_MAJOR);