SAFE public projects git trees. - safe/jmp/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/config.h>
  37 #include <linux/linkage.h>
  38 #include <linux/raid/md.h>
  39 #include <linux/raid/bitmap.h>
  40 #include <linux/sysctl.h>
  41 #include <linux/devfs_fs_kernel.h>
  42 #include <linux/buffer_head.h> /* for invalidate_bdev */
  43 #include <linux/suspend.h>
  44
  45 #include <linux/init.h>
  46
  47 #include <linux/file.h>
  48
  49 #ifdef CONFIG_KMOD
  50 #include <linux/kmod.h>
  51 #endif
  52
  53 #include <asm/unaligned.h>
  54
  55 #define MAJOR_NR MD_MAJOR
  56 #define MD_DRIVER
  57
  58 /* 63 partitions with the alternate major number (mdp) */
  59 #define MdpMinorShift 6
  60
  61 #define DEBUG 0
  62 #define dprintk(x...) ((void)(DEBUG && printk(x)))
  63
  64
  65 #ifndef MODULE
  66 static void autostart_arrays (int part);
  67 #endif
  68
  69 static mdk_personality_t *pers[MAX_PERSONALITY];
  70 static DEFINE_SPINLOCK(pers_lock);
  71
  72 /*
  73  * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
  74  * is 1000 KB/sec, so the extra system load does not show up that much.
  75  * Increase it if you want to have more _guaranteed_ speed. Note that
  76  * the RAID driver will use the maximum available bandwith if the IO
  77  * subsystem is idle. There is also an 'absolute maximum' reconstruction
  78  * speed limit - in case reconstruction slows down your system despite
  79  * idle IO detection.
  80  *
  81  * you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
  82  */
  83
  84 static int sysctl_speed_limit_min = 1000;
  85 static int sysctl_speed_limit_max = 200000;
  86
  87 static struct ctl_table_header *raid_table_header;
  88
  89 static ctl_table raid_table[] = {
  90         {
  91                 .ctl_name       = DEV_RAID_SPEED_LIMIT_MIN,
  92                 .procname       = "speed_limit_min",
  93                 .data           = &sysctl_speed_limit_min,
  94                 .maxlen         = sizeof(int),
  95                 .mode           = 0644,
  96                 .proc_handler   = &proc_dointvec,
  97         },
  98         {
  99                 .ctl_name       = DEV_RAID_SPEED_LIMIT_MAX,
 100                 .procname       = "speed_limit_max",
 101                 .data           = &sysctl_speed_limit_max,
 102                 .maxlen         = sizeof(int),
 103                 .mode           = 0644,
 104                 .proc_handler   = &proc_dointvec,
 105         },
 106         { .ctl_name = 0 }
 107 };
 108
 109 static ctl_table raid_dir_table[] = {
 110         {
 111                 .ctl_name       = DEV_RAID,
 112                 .procname       = "raid",
 113                 .maxlen         = 0,
 114                 .mode           = 0555,
 115                 .child          = raid_table,
 116         },
 117         { .ctl_name = 0 }
 118 };
 119
 120 static ctl_table raid_root_table[] = {
 121         {
 122                 .ctl_name       = CTL_DEV,
 123                 .procname       = "dev",
 124                 .maxlen         = 0,
 125                 .mode           = 0555,
 126                 .child          = raid_dir_table,
 127         },
 128         { .ctl_name = 0 }
 129 };
 130
 131 static struct block_device_operations md_fops;
 132
 133 /*
 134  * Enables to iterate over all existing md arrays
 135  * all_mddevs_lock protects this list.
 136  */
 137 static LIST_HEAD(all_mddevs);
 138 static DEFINE_SPINLOCK(all_mddevs_lock);
 139
 140
 141 /*
 142  * iterates through all used mddevs in the system.
 143  * We take care to grab the all_mddevs_lock whenever navigating
 144  * the list, and to always hold a refcount when unlocked.
 145  * Any code which breaks out of this loop while own
 146  * a reference to the current mddev and must mddev_put it.
 147  */
 148 #define ITERATE_MDDEV(mddev,tmp)                                        \
 149                                                                         \
 150         for (({ spin_lock(&all_mddevs_lock);                            \
 151                 tmp = all_mddevs.next;                                  \
 152                 mddev = NULL;});                                        \
 153              ({ if (tmp != &all_mddevs)                                 \
 154                         mddev_get(list_entry(tmp, mddev_t, all_mddevs));\
 155                 spin_unlock(&all_mddevs_lock);                          \
 156                 if (mddev) mddev_put(mddev);                            \
 157                 mddev = list_entry(tmp, mddev_t, all_mddevs);           \
 158                 tmp != &all_mddevs;});                                  \
 159              ({ spin_lock(&all_mddevs_lock);                            \
 160                 tmp = tmp->next;})                                      \
 161                 )
 162
 163
 164 static int md_fail_request (request_queue_t *q, struct bio *bio)
 165 {
 166         bio_io_error(bio, bio->bi_size);
 167         return 0;
 168 }
 169
 170 static inline mddev_t *mddev_get(mddev_t *mddev)
 171 {
 172         atomic_inc(&mddev->active);
 173         return mddev;
 174 }
 175
 176 static void mddev_put(mddev_t *mddev)
 177 {
 178         if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
 179                 return;
 180         if (!mddev->raid_disks && list_empty(&mddev->disks)) {
 181                 list_del(&mddev->all_mddevs);
 182                 blk_put_queue(mddev->queue);
 183                 kfree(mddev);
 184         }
 185         spin_unlock(&all_mddevs_lock);
 186 }
 187
 188 static mddev_t * mddev_find(dev_t unit)
 189 {
 190         mddev_t *mddev, *new = NULL;
 191
 192  retry:
 193         spin_lock(&all_mddevs_lock);
 194         list_for_each_entry(mddev, &all_mddevs, all_mddevs)
 195                 if (mddev->unit == unit) {
 196                         mddev_get(mddev);
 197                         spin_unlock(&all_mddevs_lock);
 198                         kfree(new);
 199                         return mddev;
 200                 }
 201
 202         if (new) {
 203                 list_add(&new->all_mddevs, &all_mddevs);
 204                 spin_unlock(&all_mddevs_lock);
 205                 return new;
 206         }
 207         spin_unlock(&all_mddevs_lock);
 208
 209         new = (mddev_t *) kmalloc(sizeof(*new), GFP_KERNEL);
 210         if (!new)
 211                 return NULL;
 212
 213         memset(new, 0, sizeof(*new));
 214
 215         new->unit = unit;
 216         if (MAJOR(unit) == MD_MAJOR)
 217                 new->md_minor = MINOR(unit);
 218         else
 219                 new->md_minor = MINOR(unit) >> MdpMinorShift;
 220
 221         init_MUTEX(&new->reconfig_sem);
 222         INIT_LIST_HEAD(&new->disks);
 223         INIT_LIST_HEAD(&new->all_mddevs);
 224         init_timer(&new->safemode_timer);
 225         atomic_set(&new->active, 1);
 226         spin_lock_init(&new->write_lock);
 227         init_waitqueue_head(&new->sb_wait);
 228
 229         new->queue = blk_alloc_queue(GFP_KERNEL);
 230         if (!new->queue) {
 231                 kfree(new);
 232                 return NULL;
 233         }
 234
 235         blk_queue_make_request(new->queue, md_fail_request);
 236
 237         goto retry;
 238 }
 239
 240 static inline int mddev_lock(mddev_t * mddev)
 241 {
 242         return down_interruptible(&mddev->reconfig_sem);
 243 }
 244
 245 static inline void mddev_lock_uninterruptible(mddev_t * mddev)
 246 {
 247         down(&mddev->reconfig_sem);
 248 }
 249
 250 static inline int mddev_trylock(mddev_t * mddev)
 251 {
 252         return down_trylock(&mddev->reconfig_sem);
 253 }
 254
 255 static inline void mddev_unlock(mddev_t * mddev)
 256 {
 257         up(&mddev->reconfig_sem);
 258
 259         if (mddev->thread)
 260                 md_wakeup_thread(mddev->thread);
 261 }
 262
 263 mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr)
 264 {
 265         mdk_rdev_t * rdev;
 266         struct list_head *tmp;
 267
 268         ITERATE_RDEV(mddev,rdev,tmp) {
 269                 if (rdev->desc_nr == nr)
 270                         return rdev;
 271         }
 272         return NULL;
 273 }
 274
 275 static mdk_rdev_t * find_rdev(mddev_t * mddev, dev_t dev)
 276 {
 277         struct list_head *tmp;
 278         mdk_rdev_t *rdev;
 279
 280         ITERATE_RDEV(mddev,rdev,tmp) {
 281                 if (rdev->bdev->bd_dev == dev)
 282                         return rdev;
 283         }
 284         return NULL;
 285 }
 286
 287 inline static sector_t calc_dev_sboffset(struct block_device *bdev)
 288 {
 289         sector_t size = bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
 290         return MD_NEW_SIZE_BLOCKS(size);
 291 }
 292
 293 static sector_t calc_dev_size(mdk_rdev_t *rdev, unsigned chunk_size)
 294 {
 295         sector_t size;
 296
 297         size = rdev->sb_offset;
 298
 299         if (chunk_size)
 300                 size &= ~((sector_t)chunk_size/1024 - 1);
 301         return size;
 302 }
 303
 304 static int alloc_disk_sb(mdk_rdev_t * rdev)
 305 {
 306         if (rdev->sb_page)
 307                 MD_BUG();
 308
 309         rdev->sb_page = alloc_page(GFP_KERNEL);
 310         if (!rdev->sb_page) {
 311                 printk(KERN_ALERT "md: out of memory.\n");
 312                 return -EINVAL;
 313         }
 314
 315         return 0;
 316 }
 317
 318 static void free_disk_sb(mdk_rdev_t * rdev)
 319 {
 320         if (rdev->sb_page) {
 321                 page_cache_release(rdev->sb_page);
 322                 rdev->sb_loaded = 0;
 323                 rdev->sb_page = NULL;
 324                 rdev->sb_offset = 0;
 325                 rdev->size = 0;
 326         }
 327 }
 328
 329
 330 static int super_written(struct bio *bio, unsigned int bytes_done, int error)
 331 {
 332         mdk_rdev_t *rdev = bio->bi_private;
 333         if (bio->bi_size)
 334                 return 1;
 335
 336         if (error || !test_bit(BIO_UPTODATE, &bio->bi_flags))
 337                 md_error(rdev->mddev, rdev);
 338
 339         if (atomic_dec_and_test(&rdev->mddev->pending_writes))
 340                 wake_up(&rdev->mddev->sb_wait);
 341         return 0;
 342 }
 343
 344 void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev,
 345                    sector_t sector, int size, struct page *page)
 346 {
 347         /* write first size bytes of page to sector of rdev
 348          * Increment mddev->pending_writes before returning
 349          * and decrement it on completion, waking up sb_wait
 350          * if zero is reached.
 351          * If an error occurred, call md_error
 352          */
 353         struct bio *bio = bio_alloc(GFP_NOIO, 1);
 354
 355         bio->bi_bdev = rdev->bdev;
 356         bio->bi_sector = sector;
 357         bio_add_page(bio, page, size, 0);
 358         bio->bi_private = rdev;
 359         bio->bi_end_io = super_written;
 360         atomic_inc(&mddev->pending_writes);
 361         submit_bio((1<<BIO_RW)|(1<<BIO_RW_SYNC), bio);
 362 }
 363
 364 static int bi_complete(struct bio *bio, unsigned int bytes_done, int error)
 365 {
 366         if (bio->bi_size)
 367                 return 1;
 368
 369         complete((struct completion*)bio->bi_private);
 370         return 0;
 371 }
 372
 373 int sync_page_io(struct block_device *bdev, sector_t sector, int size,
 374                    struct page *page, int rw)
 375 {
 376         struct bio *bio = bio_alloc(GFP_NOIO, 1);
 377         struct completion event;
 378         int ret;
 379
 380         rw |= (1 << BIO_RW_SYNC);
 381
 382         bio->bi_bdev = bdev;
 383         bio->bi_sector = sector;
 384         bio_add_page(bio, page, size, 0);
 385         init_completion(&event);
 386         bio->bi_private = &event;
 387         bio->bi_end_io = bi_complete;
 388         submit_bio(rw, bio);
 389         wait_for_completion(&event);
 390
 391         ret = test_bit(BIO_UPTODATE, &bio->bi_flags);
 392         bio_put(bio);
 393         return ret;
 394 }
 395
 396 static int read_disk_sb(mdk_rdev_t * rdev)
 397 {
 398         char b[BDEVNAME_SIZE];
 399         if (!rdev->sb_page) {
 400                 MD_BUG();
 401                 return -EINVAL;
 402         }
 403         if (rdev->sb_loaded)
 404                 return 0;
 405
 406
 407         if (!sync_page_io(rdev->bdev, rdev->sb_offset<<1, MD_SB_BYTES, rdev->sb_page, READ))
 408                 goto fail;
 409         rdev->sb_loaded = 1;
 410         return 0;
 411
 412 fail:
 413         printk(KERN_WARNING "md: disabled device %s, could not read superblock.\n",
 414                 bdevname(rdev->bdev,b));
 415         return -EINVAL;
 416 }
 417
 418 static int uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 419 {
 420         if (    (sb1->set_uuid0 == sb2->set_uuid0) &&
 421                 (sb1->set_uuid1 == sb2->set_uuid1) &&
 422                 (sb1->set_uuid2 == sb2->set_uuid2) &&
 423                 (sb1->set_uuid3 == sb2->set_uuid3))
 424
 425                 return 1;
 426
 427         return 0;
 428 }
 429
 430
 431 static int sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 432 {
 433         int ret;
 434         mdp_super_t *tmp1, *tmp2;
 435
 436         tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
 437         tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
 438
 439         if (!tmp1 || !tmp2) {
 440                 ret = 0;
 441                 printk(KERN_INFO "md.c: sb1 is not equal to sb2!\n");
 442                 goto abort;
 443         }
 444
 445         *tmp1 = *sb1;
 446         *tmp2 = *sb2;
 447
 448         /*
 449          * nr_disks is not constant
 450          */
 451         tmp1->nr_disks = 0;
 452         tmp2->nr_disks = 0;
 453
 454         if (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4))
 455                 ret = 0;
 456         else
 457                 ret = 1;
 458
 459 abort:
 460         kfree(tmp1);
 461         kfree(tmp2);
 462         return ret;
 463 }
 464
 465 static unsigned int calc_sb_csum(mdp_super_t * sb)
 466 {
 467         unsigned int disk_csum, csum;
 468
 469         disk_csum = sb->sb_csum;
 470         sb->sb_csum = 0;
 471         csum = csum_partial((void *)sb, MD_SB_BYTES, 0);
 472         sb->sb_csum = disk_csum;
 473         return csum;
 474 }
 475
 476
 477 /*
 478  * Handle superblock details.
 479  * We want to be able to handle multiple superblock formats
 480  * so we have a common interface to them all, and an array of
 481  * different handlers.
 482  * We rely on user-space to write the initial superblock, and support
 483  * reading and updating of superblocks.
 484  * Interface methods are:
 485  *   int load_super(mdk_rdev_t *dev, mdk_rdev_t *refdev, int minor_version)
 486  *      loads and validates a superblock on dev.
 487  *      if refdev != NULL, compare superblocks on both devices
 488  *    Return:
 489  *      0 - dev has a superblock that is compatible with refdev
 490  *      1 - dev has a superblock that is compatible and newer than refdev
 491  *          so dev should be used as the refdev in future
 492  *     -EINVAL superblock incompatible or invalid
 493  *     -othererror e.g. -EIO
 494  *
 495  *   int validate_super(mddev_t *mddev, mdk_rdev_t *dev)
 496  *      Verify that dev is acceptable into mddev.
 497  *       The first time, mddev->raid_disks will be 0, and data from
 498  *       dev should be merged in.  Subsequent calls check that dev
 499  *       is new enough.  Return 0 or -EINVAL
 500  *
 501  *   void sync_super(mddev_t *mddev, mdk_rdev_t *dev)
 502  *     Update the superblock for rdev with data in mddev
 503  *     This does not write to disc.
 504  *
 505  */
 506
 507 struct super_type  {
 508         char            *name;
 509         struct module   *owner;
 510         int             (*load_super)(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version);
 511         int             (*validate_super)(mddev_t *mddev, mdk_rdev_t *rdev);
 512         void            (*sync_super)(mddev_t *mddev, mdk_rdev_t *rdev);
 513 };
 514
 515 /*
 516  * load_super for 0.90.0
 517  */
 518 static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
 519 {
 520         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
 521         mdp_super_t *sb;
 522         int ret;
 523         sector_t sb_offset;
 524
 525         /*
 526          * Calculate the position of the superblock,
 527          * it's at the end of the disk.
 528          *
 529          * It also happens to be a multiple of 4Kb.
 530          */
 531         sb_offset = calc_dev_sboffset(rdev->bdev);
 532         rdev->sb_offset = sb_offset;
 533
 534         ret = read_disk_sb(rdev);
 535         if (ret) return ret;
 536
 537         ret = -EINVAL;
 538
 539         bdevname(rdev->bdev, b);
 540         sb = (mdp_super_t*)page_address(rdev->sb_page);
 541
 542         if (sb->md_magic != MD_SB_MAGIC) {
 543                 printk(KERN_ERR "md: invalid raid superblock magic on %s\n",
 544                        b);
 545                 goto abort;
 546         }
 547
 548         if (sb->major_version != 0 ||
 549             sb->minor_version != 90) {
 550                 printk(KERN_WARNING "Bad version number %d.%d on %s\n",
 551                         sb->major_version, sb->minor_version,
 552                         b);
 553                 goto abort;
 554         }
 555
 556         if (sb->raid_disks <= 0)
 557                 goto abort;
 558
 559         if (csum_fold(calc_sb_csum(sb)) != csum_fold(sb->sb_csum)) {
 560                 printk(KERN_WARNING "md: invalid superblock checksum on %s\n",
 561                         b);
 562                 goto abort;
 563         }
 564
 565         rdev->preferred_minor = sb->md_minor;
 566         rdev->data_offset = 0;
 567
 568         if (sb->level == LEVEL_MULTIPATH)
 569                 rdev->desc_nr = -1;
 570         else
 571                 rdev->desc_nr = sb->this_disk.number;
 572
 573         if (refdev == 0)
 574                 ret = 1;
 575         else {
 576                 __u64 ev1, ev2;
 577                 mdp_super_t *refsb = (mdp_super_t*)page_address(refdev->sb_page);
 578                 if (!uuid_equal(refsb, sb)) {
 579                         printk(KERN_WARNING "md: %s has different UUID to %s\n",
 580                                 b, bdevname(refdev->bdev,b2));
 581                         goto abort;
 582                 }
 583                 if (!sb_equal(refsb, sb)) {
 584                         printk(KERN_WARNING "md: %s has same UUID"
 585                                " but different superblock to %s\n",
 586                                b, bdevname(refdev->bdev, b2));
 587                         goto abort;
 588                 }
 589                 ev1 = md_event(sb);
 590                 ev2 = md_event(refsb);
 591                 if (ev1 > ev2)
 592                         ret = 1;
 593                 else
 594                         ret = 0;
 595         }
 596         rdev->size = calc_dev_size(rdev, sb->chunk_size);
 597
 598  abort:
 599         return ret;
 600 }
 601
 602 /*
 603  * validate_super for 0.90.0
 604  */
 605 static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
 606 {
 607         mdp_disk_t *desc;
 608         mdp_super_t *sb = (mdp_super_t *)page_address(rdev->sb_page);
 609
 610         rdev->raid_disk = -1;
 611         rdev->in_sync = 0;
 612         if (mddev->raid_disks == 0) {
 613                 mddev->major_version = 0;
 614                 mddev->minor_version = sb->minor_version;
 615                 mddev->patch_version = sb->patch_version;
 616                 mddev->persistent = ! sb->not_persistent;
 617                 mddev->chunk_size = sb->chunk_size;
 618                 mddev->ctime = sb->ctime;
 619                 mddev->utime = sb->utime;
 620                 mddev->level = sb->level;
 621                 mddev->layout = sb->layout;
 622                 mddev->raid_disks = sb->raid_disks;
 623                 mddev->size = sb->size;
 624                 mddev->events = md_event(sb);
 625
 626                 if (sb->state & (1<<MD_SB_CLEAN))
 627                         mddev->recovery_cp = MaxSector;
 628                 else {
 629                         if (sb->events_hi == sb->cp_events_hi &&
 630                                 sb->events_lo == sb->cp_events_lo) {
 631                                 mddev->recovery_cp = sb->recovery_cp;
 632                         } else
 633                                 mddev->recovery_cp = 0;
 634                 }
 635
 636                 memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
 637                 memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
 638                 memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
 639                 memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
 640
 641                 mddev->max_disks = MD_SB_DISKS;
 642
 643                 if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
 644                     mddev->bitmap_file == NULL) {
 645                         if (mddev->level != 1) {
 646                                 /* FIXME use a better test */
 647                                 printk(KERN_WARNING "md: bitmaps only support for raid1\n");
 648                                 return -EINVAL;
 649                         }
 650                         mddev->bitmap_offset = (MD_SB_BYTES >> 9);
 651                 }
 652
 653         } else if (mddev->pers == NULL) {
 654                 /* Insist on good event counter while assembling */
 655                 __u64 ev1 = md_event(sb);
 656                 ++ev1;
 657                 if (ev1 < mddev->events)
 658                         return -EINVAL;
 659         } else if (mddev->bitmap) {
 660                 /* if adding to array with a bitmap, then we can accept an
 661                  * older device ... but not too old.
 662                  */
 663                 __u64 ev1 = md_event(sb);
 664                 if (ev1 < mddev->bitmap->events_cleared)
 665                         return 0;
 666         } else /* just a hot-add of a new device, leave raid_disk at -1 */
 667                 return 0;
 668
 669         if (mddev->level != LEVEL_MULTIPATH) {
 670                 rdev->faulty = 0;
 671                 desc = sb->disks + rdev->desc_nr;
 672
 673                 if (desc->state & (1<<MD_DISK_FAULTY))
 674                         rdev->faulty = 1;
 675                 else if (desc->state & (1<<MD_DISK_SYNC) &&
 676                          desc->raid_disk < mddev->raid_disks) {
 677                         rdev->in_sync = 1;
 678                         rdev->raid_disk = desc->raid_disk;
 679                 }
 680         } else /* MULTIPATH are always insync */
 681                 rdev->in_sync = 1;
 682         return 0;
 683 }
 684
 685 /*
 686  * sync_super for 0.90.0
 687  */
 688 static void super_90_sync(mddev_t *mddev, mdk_rdev_t *rdev)
 689 {
 690         mdp_super_t *sb;
 691         struct list_head *tmp;
 692         mdk_rdev_t *rdev2;
 693         int next_spare = mddev->raid_disks;
 694
 695         /* make rdev->sb match mddev data..
 696          *
 697          * 1/ zero out disks
 698          * 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
 699          * 3/ any empty disks < next_spare become removed
 700          *
 701          * disks[0] gets initialised to REMOVED because
 702          * we cannot be sure from other fields if it has
 703          * been initialised or not.
 704          */
 705         int i;
 706         int active=0, working=0,failed=0,spare=0,nr_disks=0;
 707
 708         sb = (mdp_super_t*)page_address(rdev->sb_page);
 709
 710         memset(sb, 0, sizeof(*sb));
 711
 712         sb->md_magic = MD_SB_MAGIC;
 713         sb->major_version = mddev->major_version;
 714         sb->minor_version = mddev->minor_version;
 715         sb->patch_version = mddev->patch_version;
 716         sb->gvalid_words  = 0; /* ignored */
 717         memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
 718         memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
 719         memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
 720         memcpy(&sb->set_uuid3, mddev->uuid+12,4);
 721
 722         sb->ctime = mddev->ctime;
 723         sb->level = mddev->level;
 724         sb->size  = mddev->size;
 725         sb->raid_disks = mddev->raid_disks;
 726         sb->md_minor = mddev->md_minor;
 727         sb->not_persistent = !mddev->persistent;
 728         sb->utime = mddev->utime;
 729         sb->state = 0;
 730         sb->events_hi = (mddev->events>>32);
 731         sb->events_lo = (u32)mddev->events;
 732
 733         if (mddev->in_sync)
 734         {
 735                 sb->recovery_cp = mddev->recovery_cp;
 736                 sb->cp_events_hi = (mddev->events>>32);
 737                 sb->cp_events_lo = (u32)mddev->events;
 738                 if (mddev->recovery_cp == MaxSector)
 739                         sb->state = (1<< MD_SB_CLEAN);
 740         } else
 741                 sb->recovery_cp = 0;
 742
 743         sb->layout = mddev->layout;
 744         sb->chunk_size = mddev->chunk_size;
 745
 746         if (mddev->bitmap && mddev->bitmap_file == NULL)
 747                 sb->state |= (1<<MD_SB_BITMAP_PRESENT);
 748
 749         sb->disks[0].state = (1<<MD_DISK_REMOVED);
 750         ITERATE_RDEV(mddev,rdev2,tmp) {
 751                 mdp_disk_t *d;
 752                 if (rdev2->raid_disk >= 0 && rdev2->in_sync && !rdev2->faulty)
 753                         rdev2->desc_nr = rdev2->raid_disk;
 754                 else
 755                         rdev2->desc_nr = next_spare++;
 756                 d = &sb->disks[rdev2->desc_nr];
 757                 nr_disks++;
 758                 d->number = rdev2->desc_nr;
 759                 d->major = MAJOR(rdev2->bdev->bd_dev);
 760                 d->minor = MINOR(rdev2->bdev->bd_dev);
 761                 if (rdev2->raid_disk >= 0 && rdev->in_sync && !rdev2->faulty)
 762                         d->raid_disk = rdev2->raid_disk;
 763                 else
 764                         d->raid_disk = rdev2->desc_nr; /* compatibility */
 765                 if (rdev2->faulty) {
 766                         d->state = (1<<MD_DISK_FAULTY);
 767                         failed++;
 768                 } else if (rdev2->in_sync) {
 769                         d->state = (1<<MD_DISK_ACTIVE);
 770                         d->state |= (1<<MD_DISK_SYNC);
 771                         active++;
 772                         working++;
 773                 } else {
 774                         d->state = 0;
 775                         spare++;
 776                         working++;
 777                 }
 778         }
 779
 780         /* now set the "removed" and "faulty" bits on any missing devices */
 781         for (i=0 ; i < mddev->raid_disks ; i++) {
 782                 mdp_disk_t *d = &sb->disks[i];
 783                 if (d->state == 0 && d->number == 0) {
 784                         d->number = i;
 785                         d->raid_disk = i;
 786                         d->state = (1<<MD_DISK_REMOVED);
 787                         d->state |= (1<<MD_DISK_FAULTY);
 788                         failed++;
 789                 }
 790         }
 791         sb->nr_disks = nr_disks;
 792         sb->active_disks = active;
 793         sb->working_disks = working;
 794         sb->failed_disks = failed;
 795         sb->spare_disks = spare;
 796
 797         sb->this_disk = sb->disks[rdev->desc_nr];
 798         sb->sb_csum = calc_sb_csum(sb);
 799 }
 800
 801 /*
 802  * version 1 superblock
 803  */
 804
 805 static unsigned int calc_sb_1_csum(struct mdp_superblock_1 * sb)
 806 {
 807         unsigned int disk_csum, csum;
 808         unsigned long long newcsum;
 809         int size = 256 + le32_to_cpu(sb->max_dev)*2;
 810         unsigned int *isuper = (unsigned int*)sb;
 811         int i;
 812
 813         disk_csum = sb->sb_csum;
 814         sb->sb_csum = 0;
 815         newcsum = 0;
 816         for (i=0; size>=4; size -= 4 )
 817                 newcsum += le32_to_cpu(*isuper++);
 818
 819         if (size == 2)
 820                 newcsum += le16_to_cpu(*(unsigned short*) isuper);
 821
 822         csum = (newcsum & 0xffffffff) + (newcsum >> 32);
 823         sb->sb_csum = disk_csum;
 824         return cpu_to_le32(csum);
 825 }
 826
 827 static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
 828 {
 829         struct mdp_superblock_1 *sb;
 830         int ret;
 831         sector_t sb_offset;
 832         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
 833
 834         /*
 835          * Calculate the position of the superblock.
 836          * It is always aligned to a 4K boundary and
 837          * depeding on minor_version, it can be:
 838          * 0: At least 8K, but less than 12K, from end of device
 839          * 1: At start of device
 840          * 2: 4K from start of device.
 841          */
 842         switch(minor_version) {
 843         case 0:
 844                 sb_offset = rdev->bdev->bd_inode->i_size >> 9;
 845                 sb_offset -= 8*2;
 846                 sb_offset &= ~(sector_t)(4*2-1);
 847                 /* convert from sectors to K */
 848                 sb_offset /= 2;
 849                 break;
 850         case 1:
 851                 sb_offset = 0;
 852                 break;
 853         case 2:
 854                 sb_offset = 4;
 855                 break;
 856         default:
 857                 return -EINVAL;
 858         }
 859         rdev->sb_offset = sb_offset;
 860
 861         ret = read_disk_sb(rdev);
 862         if (ret) return ret;
 863
 864
 865         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
 866
 867         if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
 868             sb->major_version != cpu_to_le32(1) ||
 869             le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
 870             le64_to_cpu(sb->super_offset) != (rdev->sb_offset<<1) ||
 871             sb->feature_map != 0)
 872                 return -EINVAL;
 873
 874         if (calc_sb_1_csum(sb) != sb->sb_csum) {
 875                 printk("md: invalid superblock checksum on %s\n",
 876                         bdevname(rdev->bdev,b));
 877                 return -EINVAL;
 878         }
 879         if (le64_to_cpu(sb->data_size) < 10) {
 880                 printk("md: data_size too small on %s\n",
 881                        bdevname(rdev->bdev,b));
 882                 return -EINVAL;
 883         }
 884         rdev->preferred_minor = 0xffff;
 885         rdev->data_offset = le64_to_cpu(sb->data_offset);
 886
 887         if (refdev == 0)
 888                 return 1;
 889         else {
 890                 __u64 ev1, ev2;
 891                 struct mdp_superblock_1 *refsb =
 892                         (struct mdp_superblock_1*)page_address(refdev->sb_page);
 893
 894                 if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
 895                     sb->level != refsb->level ||
 896                     sb->layout != refsb->layout ||
 897                     sb->chunksize != refsb->chunksize) {
 898                         printk(KERN_WARNING "md: %s has strangely different"
 899                                 " superblock to %s\n",
 900                                 bdevname(rdev->bdev,b),
 901                                 bdevname(refdev->bdev,b2));
 902                         return -EINVAL;
 903                 }
 904                 ev1 = le64_to_cpu(sb->events);
 905                 ev2 = le64_to_cpu(refsb->events);
 906
 907                 if (ev1 > ev2)
 908                         return 1;
 909         }
 910         if (minor_version)
 911                 rdev->size = ((rdev->bdev->bd_inode->i_size>>9) - le64_to_cpu(sb->data_offset)) / 2;
 912         else
 913                 rdev->size = rdev->sb_offset;
 914         if (rdev->size < le64_to_cpu(sb->data_size)/2)
 915                 return -EINVAL;
 916         rdev->size = le64_to_cpu(sb->data_size)/2;
 917         if (le32_to_cpu(sb->chunksize))
 918                 rdev->size &= ~((sector_t)le32_to_cpu(sb->chunksize)/2 - 1);
 919         return 0;
 920 }
 921
 922 static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
 923 {
 924         struct mdp_superblock_1 *sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
 925
 926         rdev->raid_disk = -1;
 927         rdev->in_sync = 0;
 928         if (mddev->raid_disks == 0) {
 929                 mddev->major_version = 1;
 930                 mddev->patch_version = 0;
 931                 mddev->persistent = 1;
 932                 mddev->chunk_size = le32_to_cpu(sb->chunksize) << 9;
 933                 mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);
 934                 mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);
 935                 mddev->level = le32_to_cpu(sb->level);
 936                 mddev->layout = le32_to_cpu(sb->layout);
 937                 mddev->raid_disks = le32_to_cpu(sb->raid_disks);
 938                 mddev->size = le64_to_cpu(sb->size)/2;
 939                 mddev->events = le64_to_cpu(sb->events);
 940
 941                 mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
 942                 memcpy(mddev->uuid, sb->set_uuid, 16);
 943
 944                 mddev->max_disks =  (4096-256)/2;
 945
 946                 if ((le32_to_cpu(sb->feature_map) & 1) &&
 947                     mddev->bitmap_file == NULL ) {
 948                         if (mddev->level != 1) {
 949                                 printk(KERN_WARNING "md: bitmaps only supported for raid1\n");
 950                                 return -EINVAL;
 951                         }
 952                         mddev->bitmap_offset = (__s32)le32_to_cpu(sb->bitmap_offset);
 953                 }
 954         } else if (mddev->pers == NULL) {
 955                 /* Insist of good event counter while assembling */
 956                 __u64 ev1 = le64_to_cpu(sb->events);
 957                 ++ev1;
 958                 if (ev1 < mddev->events)
 959                         return -EINVAL;
 960         } else if (mddev->bitmap) {
 961                 /* If adding to array with a bitmap, then we can accept an
 962                  * older device, but not too old.
 963                  */
 964                 __u64 ev1 = le64_to_cpu(sb->events);
 965                 if (ev1 < mddev->bitmap->events_cleared)
 966                         return 0;
 967         } else /* just a hot-add of a new device, leave raid_disk at -1 */
 968                 return 0;
 969
 970         if (mddev->level != LEVEL_MULTIPATH) {
 971                 int role;
 972                 rdev->desc_nr = le32_to_cpu(sb->dev_number);
 973                 role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
 974                 switch(role) {
 975                 case 0xffff: /* spare */
 976                         rdev->faulty = 0;
 977                         break;
 978                 case 0xfffe: /* faulty */
 979                         rdev->faulty = 1;
 980                         break;
 981                 default:
 982                         rdev->in_sync = 1;
 983                         rdev->faulty = 0;
 984                         rdev->raid_disk = role;
 985                         break;
 986                 }
 987         } else /* MULTIPATH are always insync */
 988                 rdev->in_sync = 1;
 989
 990         return 0;
 991 }
 992
 993 static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
 994 {
 995         struct mdp_superblock_1 *sb;
 996         struct list_head *tmp;
 997         mdk_rdev_t *rdev2;
 998         int max_dev, i;
 999         /* make rdev->sb match mddev and rdev data. */
1000
1001         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1002
1003         sb->feature_map = 0;
1004         sb->pad0 = 0;
1005         memset(sb->pad1, 0, sizeof(sb->pad1));
1006         memset(sb->pad2, 0, sizeof(sb->pad2));
1007         memset(sb->pad3, 0, sizeof(sb->pad3));
1008
1009         sb->utime = cpu_to_le64((__u64)mddev->utime);
1010         sb->events = cpu_to_le64(mddev->events);
1011         if (mddev->in_sync)
1012                 sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
1013         else
1014                 sb->resync_offset = cpu_to_le64(0);
1015
1016         if (mddev->bitmap && mddev->bitmap_file == NULL) {
1017                 sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_offset);
1018                 sb->feature_map = cpu_to_le32(1);
1019         }
1020
1021         max_dev = 0;
1022         ITERATE_RDEV(mddev,rdev2,tmp)
1023                 if (rdev2->desc_nr+1 > max_dev)
1024                         max_dev = rdev2->desc_nr+1;
1025
1026         sb->max_dev = cpu_to_le32(max_dev);
1027         for (i=0; i<max_dev;i++)
1028                 sb->dev_roles[i] = cpu_to_le16(0xfffe);
1029
1030         ITERATE_RDEV(mddev,rdev2,tmp) {
1031                 i = rdev2->desc_nr;
1032                 if (rdev2->faulty)
1033                         sb->dev_roles[i] = cpu_to_le16(0xfffe);
1034                 else if (rdev2->in_sync)
1035                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1036                 else
1037                         sb->dev_roles[i] = cpu_to_le16(0xffff);
1038         }
1039
1040         sb->recovery_offset = cpu_to_le64(0); /* not supported yet */
1041         sb->sb_csum = calc_sb_1_csum(sb);
1042 }
1043
1044
1045 static struct super_type super_types[] = {
1046         [0] = {
1047                 .name   = "0.90.0",
1048                 .owner  = THIS_MODULE,
1049                 .load_super     = super_90_load,
1050                 .validate_super = super_90_validate,
1051                 .sync_super     = super_90_sync,
1052         },
1053         [1] = {
1054                 .name   = "md-1",
1055                 .owner  = THIS_MODULE,
1056                 .load_super     = super_1_load,
1057                 .validate_super = super_1_validate,
1058                 .sync_super     = super_1_sync,
1059         },
1060 };
1061
1062 static mdk_rdev_t * match_dev_unit(mddev_t *mddev, mdk_rdev_t *dev)
1063 {
1064         struct list_head *tmp;
1065         mdk_rdev_t *rdev;
1066
1067         ITERATE_RDEV(mddev,rdev,tmp)
1068                 if (rdev->bdev->bd_contains == dev->bdev->bd_contains)
1069                         return rdev;
1070
1071         return NULL;
1072 }
1073
1074 static int match_mddev_units(mddev_t *mddev1, mddev_t *mddev2)
1075 {
1076         struct list_head *tmp;
1077         mdk_rdev_t *rdev;
1078
1079         ITERATE_RDEV(mddev1,rdev,tmp)
1080                 if (match_dev_unit(mddev2, rdev))
1081                         return 1;
1082
1083         return 0;
1084 }
1085
1086 static LIST_HEAD(pending_raid_disks);
1087
1088 static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
1089 {
1090         mdk_rdev_t *same_pdev;
1091         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1092
1093         if (rdev->mddev) {
1094                 MD_BUG();
1095                 return -EINVAL;
1096         }
1097         same_pdev = match_dev_unit(mddev, rdev);
1098         if (same_pdev)
1099                 printk(KERN_WARNING
1100                         "%s: WARNING: %s appears to be on the same physical"
1101                         " disk as %s. True\n     protection against single-disk"
1102                         " failure might be compromised.\n",
1103                         mdname(mddev), bdevname(rdev->bdev,b),
1104                         bdevname(same_pdev->bdev,b2));
1105
1106         /* Verify rdev->desc_nr is unique.
1107          * If it is -1, assign a free number, else
1108          * check number is not in use
1109          */
1110         if (rdev->desc_nr < 0) {
1111                 int choice = 0;
1112                 if (mddev->pers) choice = mddev->raid_disks;
1113                 while (find_rdev_nr(mddev, choice))
1114                         choice++;
1115                 rdev->desc_nr = choice;
1116         } else {
1117                 if (find_rdev_nr(mddev, rdev->desc_nr))
1118                         return -EBUSY;
1119         }
1120
1121         list_add(&rdev->same_set, &mddev->disks);
1122         rdev->mddev = mddev;
1123         printk(KERN_INFO "md: bind<%s>\n", bdevname(rdev->bdev,b));
1124         return 0;
1125 }
1126
1127 static void unbind_rdev_from_array(mdk_rdev_t * rdev)
1128 {
1129         char b[BDEVNAME_SIZE];
1130         if (!rdev->mddev) {
1131                 MD_BUG();
1132                 return;
1133         }
1134         list_del_init(&rdev->same_set);
1135         printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
1136         rdev->mddev = NULL;
1137 }
1138
1139 /*
1140  * prevent the device from being mounted, repartitioned or
1141  * otherwise reused by a RAID array (or any other kernel
1142  * subsystem), by bd_claiming the device.
1143  */
1144 static int lock_rdev(mdk_rdev_t *rdev, dev_t dev)
1145 {
1146         int err = 0;
1147         struct block_device *bdev;
1148         char b[BDEVNAME_SIZE];
1149
1150         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
1151         if (IS_ERR(bdev)) {
1152                 printk(KERN_ERR "md: could not open %s.\n",
1153                         __bdevname(dev, b));
1154                 return PTR_ERR(bdev);
1155         }
1156         err = bd_claim(bdev, rdev);
1157         if (err) {
1158                 printk(KERN_ERR "md: could not bd_claim %s.\n",
1159                         bdevname(bdev, b));
1160                 blkdev_put(bdev);
1161                 return err;
1162         }
1163         rdev->bdev = bdev;
1164         return err;
1165 }
1166
1167 static void unlock_rdev(mdk_rdev_t *rdev)
1168 {
1169         struct block_device *bdev = rdev->bdev;
1170         rdev->bdev = NULL;
1171         if (!bdev)
1172                 MD_BUG();
1173         bd_release(bdev);
1174         blkdev_put(bdev);
1175 }
1176
1177 void md_autodetect_dev(dev_t dev);
1178
1179 static void export_rdev(mdk_rdev_t * rdev)
1180 {
1181         char b[BDEVNAME_SIZE];
1182         printk(KERN_INFO "md: export_rdev(%s)\n",
1183                 bdevname(rdev->bdev,b));
1184         if (rdev->mddev)
1185                 MD_BUG();
1186         free_disk_sb(rdev);
1187         list_del_init(&rdev->same_set);
1188 #ifndef MODULE
1189         md_autodetect_dev(rdev->bdev->bd_dev);
1190 #endif
1191         unlock_rdev(rdev);
1192         kfree(rdev);
1193 }
1194
1195 static void kick_rdev_from_array(mdk_rdev_t * rdev)
1196 {
1197         unbind_rdev_from_array(rdev);
1198         export_rdev(rdev);
1199 }
1200
1201 static void export_array(mddev_t *mddev)
1202 {
1203         struct list_head *tmp;
1204         mdk_rdev_t *rdev;
1205
1206         ITERATE_RDEV(mddev,rdev,tmp) {
1207                 if (!rdev->mddev) {
1208                         MD_BUG();
1209                         continue;
1210                 }
1211                 kick_rdev_from_array(rdev);
1212         }
1213         if (!list_empty(&mddev->disks))
1214                 MD_BUG();
1215         mddev->raid_disks = 0;
1216         mddev->major_version = 0;
1217 }
1218
1219 static void print_desc(mdp_disk_t *desc)
1220 {
1221         printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
1222                 desc->major,desc->minor,desc->raid_disk,desc->state);
1223 }
1224
1225 static void print_sb(mdp_super_t *sb)
1226 {
1227         int i;
1228
1229         printk(KERN_INFO
1230                 "md:  SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
1231                 sb->major_version, sb->minor_version, sb->patch_version,
1232                 sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
1233                 sb->ctime);
1234         printk(KERN_INFO "md:     L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
1235                 sb->level, sb->size, sb->nr_disks, sb->raid_disks,
1236                 sb->md_minor, sb->layout, sb->chunk_size);
1237         printk(KERN_INFO "md:     UT:%08x ST:%d AD:%d WD:%d"
1238                 " FD:%d SD:%d CSUM:%08x E:%08lx\n",
1239                 sb->utime, sb->state, sb->active_disks, sb->working_disks,
1240                 sb->failed_disks, sb->spare_disks,
1241                 sb->sb_csum, (unsigned long)sb->events_lo);
1242
1243         printk(KERN_INFO);
1244         for (i = 0; i < MD_SB_DISKS; i++) {
1245                 mdp_disk_t *desc;
1246
1247                 desc = sb->disks + i;
1248                 if (desc->number || desc->major || desc->minor ||
1249                     desc->raid_disk || (desc->state && (desc->state != 4))) {
1250                         printk("     D %2d: ", i);
1251                         print_desc(desc);
1252                 }
1253         }
1254         printk(KERN_INFO "md:     THIS: ");
1255         print_desc(&sb->this_disk);
1256
1257 }
1258
1259 static void print_rdev(mdk_rdev_t *rdev)
1260 {
1261         char b[BDEVNAME_SIZE];
1262         printk(KERN_INFO "md: rdev %s, SZ:%08llu F:%d S:%d DN:%u\n",
1263                 bdevname(rdev->bdev,b), (unsigned long long)rdev->size,
1264                 rdev->faulty, rdev->in_sync, rdev->desc_nr);
1265         if (rdev->sb_loaded) {
1266                 printk(KERN_INFO "md: rdev superblock:\n");
1267                 print_sb((mdp_super_t*)page_address(rdev->sb_page));
1268         } else
1269                 printk(KERN_INFO "md: no rdev superblock!\n");
1270 }
1271
1272 void md_print_devices(void)
1273 {
1274         struct list_head *tmp, *tmp2;
1275         mdk_rdev_t *rdev;
1276         mddev_t *mddev;
1277         char b[BDEVNAME_SIZE];
1278
1279         printk("\n");
1280         printk("md:     **********************************\n");
1281         printk("md:     * <COMPLETE RAID STATE PRINTOUT> *\n");
1282         printk("md:     **********************************\n");
1283         ITERATE_MDDEV(mddev,tmp) {
1284
1285                 if (mddev->bitmap)
1286                         bitmap_print_sb(mddev->bitmap);
1287                 else
1288                         printk("%s: ", mdname(mddev));
1289                 ITERATE_RDEV(mddev,rdev,tmp2)
1290                         printk("<%s>", bdevname(rdev->bdev,b));
1291                 printk("\n");
1292
1293                 ITERATE_RDEV(mddev,rdev,tmp2)
1294                         print_rdev(rdev);
1295         }
1296         printk("md:     **********************************\n");
1297         printk("\n");
1298 }
1299
1300
1301 static void sync_sbs(mddev_t * mddev)
1302 {
1303         mdk_rdev_t *rdev;
1304         struct list_head *tmp;
1305
1306         ITERATE_RDEV(mddev,rdev,tmp) {
1307                 super_types[mddev->major_version].
1308                         sync_super(mddev, rdev);
1309                 rdev->sb_loaded = 1;
1310         }
1311 }
1312
1313 static void md_update_sb(mddev_t * mddev)
1314 {
1315         int err;
1316         struct list_head *tmp;
1317         mdk_rdev_t *rdev;
1318         int sync_req;
1319
1320 repeat:
1321         spin_lock(&mddev->write_lock);
1322         sync_req = mddev->in_sync;
1323         mddev->utime = get_seconds();
1324         mddev->events ++;
1325
1326         if (!mddev->events) {
1327                 /*
1328                  * oops, this 64-bit counter should never wrap.
1329                  * Either we are in around ~1 trillion A.C., assuming
1330                  * 1 reboot per second, or we have a bug:
1331                  */
1332                 MD_BUG();
1333                 mddev->events --;
1334         }
1335         mddev->sb_dirty = 2;
1336         sync_sbs(mddev);
1337
1338         /*
1339          * do not write anything to disk if using
1340          * nonpersistent superblocks
1341          */
1342         if (!mddev->persistent) {
1343                 mddev->sb_dirty = 0;
1344                 spin_unlock(&mddev->write_lock);
1345                 wake_up(&mddev->sb_wait);
1346                 return;
1347         }
1348         spin_unlock(&mddev->write_lock);
1349
1350         dprintk(KERN_INFO
1351                 "md: updating %s RAID superblock on device (in sync %d)\n",
1352                 mdname(mddev),mddev->in_sync);
1353
1354         err = bitmap_update_sb(mddev->bitmap);
1355         ITERATE_RDEV(mddev,rdev,tmp) {
1356                 char b[BDEVNAME_SIZE];
1357                 dprintk(KERN_INFO "md: ");
1358                 if (rdev->faulty)
1359                         dprintk("(skipping faulty ");
1360
1361                 dprintk("%s ", bdevname(rdev->bdev,b));
1362                 if (!rdev->faulty) {
1363                         md_super_write(mddev,rdev,
1364                                        rdev->sb_offset<<1, MD_SB_BYTES,
1365                                        rdev->sb_page);
1366                         dprintk(KERN_INFO "(write) %s's sb offset: %llu\n",
1367                                 bdevname(rdev->bdev,b),
1368                                 (unsigned long long)rdev->sb_offset);
1369
1370                 } else
1371                         dprintk(")\n");
1372                 if (mddev->level == LEVEL_MULTIPATH)
1373                         /* only need to write one superblock... */
1374                         break;
1375         }
1376         wait_event(mddev->sb_wait, atomic_read(&mddev->pending_writes)==0);
1377         /* if there was a failure, sb_dirty was set to 1, and we re-write super */
1378
1379         spin_lock(&mddev->write_lock);
1380         if (mddev->in_sync != sync_req|| mddev->sb_dirty == 1) {
1381                 /* have to write it out again */
1382                 spin_unlock(&mddev->write_lock);
1383                 goto repeat;
1384         }
1385         mddev->sb_dirty = 0;
1386         spin_unlock(&mddev->write_lock);
1387         wake_up(&mddev->sb_wait);
1388
1389 }
1390
1391 /*
1392  * Import a device. If 'super_format' >= 0, then sanity check the superblock
1393  *
1394  * mark the device faulty if:
1395  *
1396  *   - the device is nonexistent (zero size)
1397  *   - the device has no valid superblock
1398  *
1399  * a faulty rdev _never_ has rdev->sb set.
1400  */
1401 static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_minor)
1402 {
1403         char b[BDEVNAME_SIZE];
1404         int err;
1405         mdk_rdev_t *rdev;
1406         sector_t size;
1407
1408         rdev = (mdk_rdev_t *) kmalloc(sizeof(*rdev), GFP_KERNEL);
1409         if (!rdev) {
1410                 printk(KERN_ERR "md: could not alloc mem for new device!\n");
1411                 return ERR_PTR(-ENOMEM);
1412         }
1413         memset(rdev, 0, sizeof(*rdev));
1414
1415         if ((err = alloc_disk_sb(rdev)))
1416                 goto abort_free;
1417
1418         err = lock_rdev(rdev, newdev);
1419         if (err)
1420                 goto abort_free;
1421
1422         rdev->desc_nr = -1;
1423         rdev->faulty = 0;
1424         rdev->in_sync = 0;
1425         rdev->data_offset = 0;
1426         atomic_set(&rdev->nr_pending, 0);
1427
1428         size = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
1429         if (!size) {
1430                 printk(KERN_WARNING
1431                         "md: %s has zero or unknown size, marking faulty!\n",
1432                         bdevname(rdev->bdev,b));
1433                 err = -EINVAL;
1434                 goto abort_free;
1435         }
1436
1437         if (super_format >= 0) {
1438                 err = super_types[super_format].
1439                         load_super(rdev, NULL, super_minor);
1440                 if (err == -EINVAL) {
1441                         printk(KERN_WARNING
1442                                 "md: %s has invalid sb, not importing!\n",
1443                                 bdevname(rdev->bdev,b));
1444                         goto abort_free;
1445                 }
1446                 if (err < 0) {
1447                         printk(KERN_WARNING
1448                                 "md: could not read %s's sb, not importing!\n",
1449                                 bdevname(rdev->bdev,b));
1450                         goto abort_free;
1451                 }
1452         }
1453         INIT_LIST_HEAD(&rdev->same_set);
1454
1455         return rdev;
1456
1457 abort_free:
1458         if (rdev->sb_page) {
1459                 if (rdev->bdev)
1460                         unlock_rdev(rdev);
1461                 free_disk_sb(rdev);
1462         }
1463         kfree(rdev);
1464         return ERR_PTR(err);
1465 }
1466
1467 /*
1468  * Check a full RAID array for plausibility
1469  */
1470
1471
1472 static void analyze_sbs(mddev_t * mddev)
1473 {
1474         int i;
1475         struct list_head *tmp;
1476         mdk_rdev_t *rdev, *freshest;
1477         char b[BDEVNAME_SIZE];
1478
1479         freshest = NULL;
1480         ITERATE_RDEV(mddev,rdev,tmp)
1481                 switch (super_types[mddev->major_version].
1482                         load_super(rdev, freshest, mddev->minor_version)) {
1483                 case 1:
1484                         freshest = rdev;
1485                         break;
1486                 case 0:
1487                         break;
1488                 default:
1489                         printk( KERN_ERR \
1490                                 "md: fatal superblock inconsistency in %s"
1491                                 " -- removing from array\n",
1492                                 bdevname(rdev->bdev,b));
1493                         kick_rdev_from_array(rdev);
1494                 }
1495
1496
1497         super_types[mddev->major_version].
1498                 validate_super(mddev, freshest);
1499
1500         i = 0;
1501         ITERATE_RDEV(mddev,rdev,tmp) {
1502                 if (rdev != freshest)
1503                         if (super_types[mddev->major_version].
1504                             validate_super(mddev, rdev)) {
1505                                 printk(KERN_WARNING "md: kicking non-fresh %s"
1506                                         " from array!\n",
1507                                         bdevname(rdev->bdev,b));
1508                                 kick_rdev_from_array(rdev);
1509                                 continue;
1510                         }
1511                 if (mddev->level == LEVEL_MULTIPATH) {
1512                         rdev->desc_nr = i++;
1513                         rdev->raid_disk = rdev->desc_nr;
1514                         rdev->in_sync = 1;
1515                 }
1516         }
1517
1518
1519
1520         if (mddev->recovery_cp != MaxSector &&
1521             mddev->level >= 1)
1522                 printk(KERN_ERR "md: %s: raid array is not clean"
1523                        " -- starting background reconstruction\n",
1524                        mdname(mddev));
1525
1526 }
1527
1528 int mdp_major = 0;
1529
1530 static struct kobject *md_probe(dev_t dev, int *part, void *data)
1531 {
1532         static DECLARE_MUTEX(disks_sem);
1533         mddev_t *mddev = mddev_find(dev);
1534         struct gendisk *disk;
1535         int partitioned = (MAJOR(dev) != MD_MAJOR);
1536         int shift = partitioned ? MdpMinorShift : 0;
1537         int unit = MINOR(dev) >> shift;
1538
1539         if (!mddev)
1540                 return NULL;
1541
1542         down(&disks_sem);
1543         if (mddev->gendisk) {
1544                 up(&disks_sem);
1545                 mddev_put(mddev);
1546                 return NULL;
1547         }
1548         disk = alloc_disk(1 << shift);
1549         if (!disk) {
1550                 up(&disks_sem);
1551                 mddev_put(mddev);
1552                 return NULL;
1553         }
1554         disk->major = MAJOR(dev);
1555         disk->first_minor = unit << shift;
1556         if (partitioned) {
1557                 sprintf(disk->disk_name, "md_d%d", unit);
1558                 sprintf(disk->devfs_name, "md/d%d", unit);
1559         } else {
1560                 sprintf(disk->disk_name, "md%d", unit);
1561                 sprintf(disk->devfs_name, "md/%d", unit);
1562         }
1563         disk->fops = &md_fops;
1564         disk->private_data = mddev;
1565         disk->queue = mddev->queue;
1566         add_disk(disk);
1567         mddev->gendisk = disk;
1568         up(&disks_sem);
1569         return NULL;
1570 }
1571
1572 void md_wakeup_thread(mdk_thread_t *thread);
1573
1574 static void md_safemode_timeout(unsigned long data)
1575 {
1576         mddev_t *mddev = (mddev_t *) data;
1577
1578         mddev->safemode = 1;
1579         md_wakeup_thread(mddev->thread);
1580 }
1581
1582
1583 static int do_md_run(mddev_t * mddev)
1584 {
1585         int pnum, err;
1586         int chunk_size;
1587         struct list_head *tmp;
1588         mdk_rdev_t *rdev;
1589         struct gendisk *disk;
1590         char b[BDEVNAME_SIZE];
1591
1592         if (list_empty(&mddev->disks))
1593                 /* cannot run an array with no devices.. */
1594                 return -EINVAL;
1595
1596         if (mddev->pers)
1597                 return -EBUSY;
1598
1599         /*
1600          * Analyze all RAID superblock(s)
1601          */
1602         if (!mddev->raid_disks)
1603                 analyze_sbs(mddev);
1604
1605         chunk_size = mddev->chunk_size;
1606         pnum = level_to_pers(mddev->level);
1607
1608         if ((pnum != MULTIPATH) && (pnum != RAID1)) {
1609                 if (!chunk_size) {
1610                         /*
1611                          * 'default chunksize' in the old md code used to
1612                          * be PAGE_SIZE, baaad.
1613                          * we abort here to be on the safe side. We don't
1614                          * want to continue the bad practice.
1615                          */
1616                         printk(KERN_ERR
1617                                 "no chunksize specified, see 'man raidtab'\n");
1618                         return -EINVAL;
1619                 }
1620                 if (chunk_size > MAX_CHUNK_SIZE) {
1621                         printk(KERN_ERR "too big chunk_size: %d > %d\n",
1622                                 chunk_size, MAX_CHUNK_SIZE);
1623                         return -EINVAL;
1624                 }
1625                 /*
1626                  * chunk-size has to be a power of 2 and multiples of PAGE_SIZE
1627                  */
1628                 if ( (1 << ffz(~chunk_size)) != chunk_size) {
1629                         printk(KERN_ERR "chunk_size of %d not valid\n", chunk_size);
1630                         return -EINVAL;
1631                 }
1632                 if (chunk_size < PAGE_SIZE) {
1633                         printk(KERN_ERR "too small chunk_size: %d < %ld\n",
1634                                 chunk_size, PAGE_SIZE);
1635                         return -EINVAL;
1636                 }
1637
1638                 /* devices must have minimum size of one chunk */
1639                 ITERATE_RDEV(mddev,rdev,tmp) {
1640                         if (rdev->faulty)
1641                                 continue;
1642                         if (rdev->size < chunk_size / 1024) {
1643                                 printk(KERN_WARNING
1644                                         "md: Dev %s smaller than chunk_size:"
1645                                         " %lluk < %dk\n",
1646                                         bdevname(rdev->bdev,b),
1647                                         (unsigned long long)rdev->size,
1648                                         chunk_size / 1024);
1649                                 return -EINVAL;
1650                         }
1651                 }
1652         }
1653
1654 #ifdef CONFIG_KMOD
1655         if (!pers[pnum])
1656         {
1657                 request_module("md-personality-%d", pnum);
1658         }
1659 #endif
1660
1661         /*
1662          * Drop all container device buffers, from now on
1663          * the only valid external interface is through the md
1664          * device.
1665          * Also find largest hardsector size
1666          */
1667         ITERATE_RDEV(mddev,rdev,tmp) {
1668                 if (rdev->faulty)
1669                         continue;
1670                 sync_blockdev(rdev->bdev);
1671                 invalidate_bdev(rdev->bdev, 0);
1672         }
1673
1674         md_probe(mddev->unit, NULL, NULL);
1675         disk = mddev->gendisk;
1676         if (!disk)
1677                 return -ENOMEM;
1678
1679         spin_lock(&pers_lock);
1680         if (!pers[pnum] || !try_module_get(pers[pnum]->owner)) {
1681                 spin_unlock(&pers_lock);
1682                 printk(KERN_WARNING "md: personality %d is not loaded!\n",
1683                        pnum);
1684                 return -EINVAL;
1685         }
1686
1687         mddev->pers = pers[pnum];
1688         spin_unlock(&pers_lock);
1689
1690         mddev->resync_max_sectors = mddev->size << 1; /* may be over-ridden by personality */
1691
1692         /* before we start the array running, initialise the bitmap */
1693         err = bitmap_create(mddev);
1694         if (err)
1695                 printk(KERN_ERR "%s: failed to create bitmap (%d)\n",
1696                         mdname(mddev), err);
1697         else
1698                 err = mddev->pers->run(mddev);
1699         if (err) {
1700                 printk(KERN_ERR "md: pers->run() failed ...\n");
1701                 module_put(mddev->pers->owner);
1702                 mddev->pers = NULL;
1703                 bitmap_destroy(mddev);
1704                 return err;
1705         }
1706         atomic_set(&mddev->writes_pending,0);
1707         mddev->safemode = 0;
1708         mddev->safemode_timer.function = md_safemode_timeout;
1709         mddev->safemode_timer.data = (unsigned long) mddev;
1710         mddev->safemode_delay = (20 * HZ)/1000 +1; /* 20 msec delay */
1711         mddev->in_sync = 1;
1712
1713         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
1714
1715         if (mddev->sb_dirty)
1716                 md_update_sb(mddev);
1717
1718         set_capacity(disk, mddev->array_size<<1);
1719
1720         /* If we call blk_queue_make_request here, it will
1721          * re-initialise max_sectors etc which may have been
1722          * refined inside -> run.  So just set the bits we need to set.
1723          * Most initialisation happended when we called
1724          * blk_queue_make_request(..., md_fail_request)
1725          * earlier.
1726          */
1727         mddev->queue->queuedata = mddev;
1728         mddev->queue->make_request_fn = mddev->pers->make_request;
1729
1730         mddev->changed = 1;
1731         return 0;
1732 }
1733
1734 static int restart_array(mddev_t *mddev)
1735 {
1736         struct gendisk *disk = mddev->gendisk;
1737         int err;
1738
1739         /*
1740          * Complain if it has no devices
1741          */
1742         err = -ENXIO;
1743         if (list_empty(&mddev->disks))
1744                 goto out;
1745
1746         if (mddev->pers) {
1747                 err = -EBUSY;
1748                 if (!mddev->ro)
1749                         goto out;
1750
1751                 mddev->safemode = 0;
1752                 mddev->ro = 0;
1753                 set_disk_ro(disk, 0);
1754
1755                 printk(KERN_INFO "md: %s switched to read-write mode.\n",
1756                         mdname(mddev));
1757                 /*
1758                  * Kick recovery or resync if necessary
1759                  */
1760                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
1761                 md_wakeup_thread(mddev->thread);
1762                 err = 0;
1763         } else {
1764                 printk(KERN_ERR "md: %s has no personality assigned.\n",
1765                         mdname(mddev));
1766                 err = -EINVAL;
1767         }
1768
1769 out:
1770         return err;
1771 }
1772
1773 static int do_md_stop(mddev_t * mddev, int ro)
1774 {
1775         int err = 0;
1776         struct gendisk *disk = mddev->gendisk;
1777
1778         if (mddev->pers) {
1779                 if (atomic_read(&mddev->active)>2) {
1780                         printk("md: %s still in use.\n",mdname(mddev));
1781                         return -EBUSY;
1782                 }
1783
1784                 if (mddev->sync_thread) {
1785                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
1786                         md_unregister_thread(mddev->sync_thread);
1787                         mddev->sync_thread = NULL;
1788                 }
1789
1790                 del_timer_sync(&mddev->safemode_timer);
1791
1792                 invalidate_partition(disk, 0);
1793
1794                 if (ro) {
1795                         err  = -ENXIO;
1796                         if (mddev->ro)
1797                                 goto out;
1798                         mddev->ro = 1;
1799                 } else {
1800                         if (mddev->ro)
1801                                 set_disk_ro(disk, 0);
1802                         blk_queue_make_request(mddev->queue, md_fail_request);
1803                         mddev->pers->stop(mddev);
1804                         module_put(mddev->pers->owner);
1805                         mddev->pers = NULL;
1806                         if (mddev->ro)
1807                                 mddev->ro = 0;
1808                 }
1809                 if (!mddev->in_sync) {
1810                         /* mark array as shutdown cleanly */
1811                         mddev->in_sync = 1;
1812                         md_update_sb(mddev);
1813                 }
1814                 if (ro)
1815                         set_disk_ro(disk, 1);
1816         }
1817
1818         bitmap_destroy(mddev);
1819         if (mddev->bitmap_file) {
1820                 atomic_set(&mddev->bitmap_file->f_dentry->d_inode->i_writecount, 1);
1821                 fput(mddev->bitmap_file);
1822                 mddev->bitmap_file = NULL;
1823         }
1824
1825         /*
1826          * Free resources if final stop
1827          */
1828         if (!ro) {
1829                 struct gendisk *disk;
1830                 printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
1831
1832                 export_array(mddev);
1833
1834                 mddev->array_size = 0;
1835                 disk = mddev->gendisk;
1836                 if (disk)
1837                         set_capacity(disk, 0);
1838                 mddev->changed = 1;
1839         } else
1840                 printk(KERN_INFO "md: %s switched to read-only mode.\n",
1841                         mdname(mddev));
1842         err = 0;
1843 out:
1844         return err;
1845 }
1846
1847 static void autorun_array(mddev_t *mddev)
1848 {
1849         mdk_rdev_t *rdev;
1850         struct list_head *tmp;
1851         int err;
1852
1853         if (list_empty(&mddev->disks))
1854                 return;
1855
1856         printk(KERN_INFO "md: running: ");
1857
1858         ITERATE_RDEV(mddev,rdev,tmp) {
1859                 char b[BDEVNAME_SIZE];
1860                 printk("<%s>", bdevname(rdev->bdev,b));
1861         }
1862         printk("\n");
1863
1864         err = do_md_run (mddev);
1865         if (err) {
1866                 printk(KERN_WARNING "md: do_md_run() returned %d\n", err);
1867                 do_md_stop (mddev, 0);
1868         }
1869 }
1870
1871 /*
1872  * lets try to run arrays based on all disks that have arrived
1873  * until now. (those are in pending_raid_disks)
1874  *
1875  * the method: pick the first pending disk, collect all disks with
1876  * the same UUID, remove all from the pending list and put them into
1877  * the 'same_array' list. Then order this list based on superblock
1878  * update time (freshest comes first), kick out 'old' disks and
1879  * compare superblocks. If everything's fine then run it.
1880  *
1881  * If "unit" is allocated, then bump its reference count
1882  */
1883 static void autorun_devices(int part)
1884 {
1885         struct list_head candidates;
1886         struct list_head *tmp;
1887         mdk_rdev_t *rdev0, *rdev;
1888         mddev_t *mddev;
1889         char b[BDEVNAME_SIZE];
1890
1891         printk(KERN_INFO "md: autorun ...\n");
1892         while (!list_empty(&pending_raid_disks)) {
1893                 dev_t dev;
1894                 rdev0 = list_entry(pending_raid_disks.next,
1895                                          mdk_rdev_t, same_set);
1896
1897                 printk(KERN_INFO "md: considering %s ...\n",
1898                         bdevname(rdev0->bdev,b));
1899                 INIT_LIST_HEAD(&candidates);
1900                 ITERATE_RDEV_PENDING(rdev,tmp)
1901                         if (super_90_load(rdev, rdev0, 0) >= 0) {
1902                                 printk(KERN_INFO "md:  adding %s ...\n",
1903                                         bdevname(rdev->bdev,b));
1904                                 list_move(&rdev->same_set, &candidates);
1905                         }
1906                 /*
1907                  * now we have a set of devices, with all of them having
1908                  * mostly sane superblocks. It's time to allocate the
1909                  * mddev.
1910                  */
1911                 if (rdev0->preferred_minor < 0 || rdev0->preferred_minor >= MAX_MD_DEVS) {
1912                         printk(KERN_INFO "md: unit number in %s is bad: %d\n",
1913                                bdevname(rdev0->bdev, b), rdev0->preferred_minor);
1914                         break;
1915                 }
1916                 if (part)
1917                         dev = MKDEV(mdp_major,
1918                                     rdev0->preferred_minor << MdpMinorShift);
1919                 else
1920                         dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
1921
1922                 md_probe(dev, NULL, NULL);
1923                 mddev = mddev_find(dev);
1924                 if (!mddev) {
1925                         printk(KERN_ERR
1926                                 "md: cannot allocate memory for md drive.\n");
1927                         break;
1928                 }
1929                 if (mddev_lock(mddev))
1930                         printk(KERN_WARNING "md: %s locked, cannot run\n",
1931                                mdname(mddev));
1932                 else if (mddev->raid_disks || mddev->major_version
1933                          || !list_empty(&mddev->disks)) {
1934                         printk(KERN_WARNING
1935                                 "md: %s already running, cannot run %s\n",
1936                                 mdname(mddev), bdevname(rdev0->bdev,b));
1937                         mddev_unlock(mddev);
1938                 } else {
1939                         printk(KERN_INFO "md: created %s\n", mdname(mddev));
1940                         ITERATE_RDEV_GENERIC(candidates,rdev,tmp) {
1941                                 list_del_init(&rdev->same_set);
1942                                 if (bind_rdev_to_array(rdev, mddev))
1943                                         export_rdev(rdev);
1944                         }
1945                         autorun_array(mddev);
1946                         mddev_unlock(mddev);
1947                 }
1948                 /* on success, candidates will be empty, on error
1949                  * it won't...
1950                  */
1951                 ITERATE_RDEV_GENERIC(candidates,rdev,tmp)
1952                         export_rdev(rdev);
1953                 mddev_put(mddev);
1954         }
1955         printk(KERN_INFO "md: ... autorun DONE.\n");
1956 }
1957
1958 /*
1959  * import RAID devices based on one partition
1960  * if possible, the array gets run as well.
1961  */
1962
1963 static int autostart_array(dev_t startdev)
1964 {
1965         char b[BDEVNAME_SIZE];
1966         int err = -EINVAL, i;
1967         mdp_super_t *sb = NULL;
1968         mdk_rdev_t *start_rdev = NULL, *rdev;
1969
1970         start_rdev = md_import_device(startdev, 0, 0);
1971         if (IS_ERR(start_rdev))
1972                 return err;
1973
1974
1975         /* NOTE: this can only work for 0.90.0 superblocks */
1976         sb = (mdp_super_t*)page_address(start_rdev->sb_page);
1977         if (sb->major_version != 0 ||
1978             sb->minor_version != 90 ) {
1979                 printk(KERN_WARNING "md: can only autostart 0.90.0 arrays\n");
1980                 export_rdev(start_rdev);
1981                 return err;
1982         }
1983
1984         if (start_rdev->faulty) {
1985                 printk(KERN_WARNING
1986                         "md: can not autostart based on faulty %s!\n",
1987                         bdevname(start_rdev->bdev,b));
1988                 export_rdev(start_rdev);
1989                 return err;
1990         }
1991         list_add(&start_rdev->same_set, &pending_raid_disks);
1992
1993         for (i = 0; i < MD_SB_DISKS; i++) {
1994                 mdp_disk_t *desc = sb->disks + i;
1995                 dev_t dev = MKDEV(desc->major, desc->minor);
1996
1997                 if (!dev)
1998                         continue;
1999                 if (dev == startdev)
2000                         continue;
2001                 if (MAJOR(dev) != desc->major || MINOR(dev) != desc->minor)
2002                         continue;
2003                 rdev = md_import_device(dev, 0, 0);
2004                 if (IS_ERR(rdev))
2005                         continue;
2006
2007                 list_add(&rdev->same_set, &pending_raid_disks);
2008         }
2009
2010         /*
2011          * possibly return codes
2012          */
2013         autorun_devices(0);
2014         return 0;
2015
2016 }
2017
2018
2019 static int get_version(void __user * arg)
2020 {
2021         mdu_version_t ver;
2022
2023         ver.major = MD_MAJOR_VERSION;
2024         ver.minor = MD_MINOR_VERSION;
2025         ver.patchlevel = MD_PATCHLEVEL_VERSION;
2026
2027         if (copy_to_user(arg, &ver, sizeof(ver)))
2028                 return -EFAULT;
2029
2030         return 0;
2031 }
2032
2033 static int get_array_info(mddev_t * mddev, void __user * arg)
2034 {
2035         mdu_array_info_t info;
2036         int nr,working,active,failed,spare;
2037         mdk_rdev_t *rdev;
2038         struct list_head *tmp;
2039
2040         nr=working=active=failed=spare=0;
2041         ITERATE_RDEV(mddev,rdev,tmp) {
2042                 nr++;
2043                 if (rdev->faulty)
2044                         failed++;
2045                 else {
2046                         working++;
2047                         if (rdev->in_sync)
2048                                 active++;
2049                         else
2050                                 spare++;
2051                 }
2052         }
2053
2054         info.major_version = mddev->major_version;
2055         info.minor_version = mddev->minor_version;
2056         info.patch_version = MD_PATCHLEVEL_VERSION;
2057         info.ctime         = mddev->ctime;
2058         info.level         = mddev->level;
2059         info.size          = mddev->size;
2060         info.nr_disks      = nr;
2061         info.raid_disks    = mddev->raid_disks;
2062         info.md_minor      = mddev->md_minor;
2063         info.not_persistent= !mddev->persistent;
2064
2065         info.utime         = mddev->utime;
2066         info.state         = 0;
2067         if (mddev->in_sync)
2068                 info.state = (1<<MD_SB_CLEAN);
2069         info.active_disks  = active;
2070         info.working_disks = working;
2071         info.failed_disks  = failed;
2072         info.spare_disks   = spare;
2073
2074         info.layout        = mddev->layout;
2075         info.chunk_size    = mddev->chunk_size;
2076
2077         if (copy_to_user(arg, &info, sizeof(info)))
2078                 return -EFAULT;
2079
2080         return 0;
2081 }
2082
2083 static int get_bitmap_file(mddev_t * mddev, void * arg)
2084 {
2085         mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
2086         char *ptr, *buf = NULL;
2087         int err = -ENOMEM;
2088
2089         file = kmalloc(sizeof(*file), GFP_KERNEL);
2090         if (!file)
2091                 goto out;
2092
2093         /* bitmap disabled, zero the first byte and copy out */
2094         if (!mddev->bitmap || !mddev->bitmap->file) {
2095                 file->pathname[0] = '\0';
2096                 goto copy_out;
2097         }
2098
2099         buf = kmalloc(sizeof(file->pathname), GFP_KERNEL);
2100         if (!buf)
2101                 goto out;
2102
2103         ptr = file_path(mddev->bitmap->file, buf, sizeof(file->pathname));
2104         if (!ptr)
2105                 goto out;
2106
2107         strcpy(file->pathname, ptr);
2108
2109 copy_out:
2110         err = 0;
2111         if (copy_to_user(arg, file, sizeof(*file)))
2112                 err = -EFAULT;
2113 out:
2114         kfree(buf);
2115         kfree(file);
2116         return err;
2117 }
2118
2119 static int get_disk_info(mddev_t * mddev, void __user * arg)
2120 {
2121         mdu_disk_info_t info;
2122         unsigned int nr;
2123         mdk_rdev_t *rdev;
2124
2125         if (copy_from_user(&info, arg, sizeof(info)))
2126                 return -EFAULT;
2127
2128         nr = info.number;
2129
2130         rdev = find_rdev_nr(mddev, nr);
2131         if (rdev) {
2132                 info.major = MAJOR(rdev->bdev->bd_dev);
2133                 info.minor = MINOR(rdev->bdev->bd_dev);
2134                 info.raid_disk = rdev->raid_disk;
2135                 info.state = 0;
2136                 if (rdev->faulty)
2137                         info.state |= (1<<MD_DISK_FAULTY);
2138                 else if (rdev->in_sync) {
2139                         info.state |= (1<<MD_DISK_ACTIVE);
2140                         info.state |= (1<<MD_DISK_SYNC);
2141                 }
2142         } else {
2143                 info.major = info.minor = 0;
2144                 info.raid_disk = -1;
2145                 info.state = (1<<MD_DISK_REMOVED);
2146         }
2147
2148         if (copy_to_user(arg, &info, sizeof(info)))
2149                 return -EFAULT;
2150
2151         return 0;
2152 }
2153
2154 static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
2155 {
2156         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
2157         mdk_rdev_t *rdev;
2158         dev_t dev = MKDEV(info->major,info->minor);
2159
2160         if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
2161                 return -EOVERFLOW;
2162
2163         if (!mddev->raid_disks) {
2164                 int err;
2165                 /* expecting a device which has a superblock */
2166                 rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
2167                 if (IS_ERR(rdev)) {
2168                         printk(KERN_WARNING
2169                                 "md: md_import_device returned %ld\n",
2170                                 PTR_ERR(rdev));
2171                         return PTR_ERR(rdev);
2172                 }
2173                 if (!list_empty(&mddev->disks)) {
2174                         mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
2175                                                         mdk_rdev_t, same_set);
2176                         int err = super_types[mddev->major_version]
2177                                 .load_super(rdev, rdev0, mddev->minor_version);
2178                         if (err < 0) {
2179                                 printk(KERN_WARNING
2180                                         "md: %s has different UUID to %s\n",
2181                                         bdevname(rdev->bdev,b),
2182                                         bdevname(rdev0->bdev,b2));
2183                                 export_rdev(rdev);
2184                                 return -EINVAL;
2185                         }
2186                 }
2187                 err = bind_rdev_to_array(rdev, mddev);
2188                 if (err)
2189                         export_rdev(rdev);
2190                 return err;
2191         }
2192
2193         /*
2194          * add_new_disk can be used once the array is assembled
2195          * to add "hot spares".  They must already have a superblock
2196          * written
2197          */
2198         if (mddev->pers) {
2199                 int err;
2200                 if (!mddev->pers->hot_add_disk) {
2201                         printk(KERN_WARNING
2202                                 "%s: personality does not support diskops!\n",
2203                                mdname(mddev));
2204                         return -EINVAL;
2205                 }
2206                 rdev = md_import_device(dev, mddev->major_version,
2207                                         mddev->minor_version);
2208                 if (IS_ERR(rdev)) {
2209                         printk(KERN_WARNING
2210                                 "md: md_import_device returned %ld\n",
2211                                 PTR_ERR(rdev));
2212                         return PTR_ERR(rdev);
2213                 }
2214                 /* set save_raid_disk if appropriate */
2215                 if (!mddev->persistent) {
2216                         if (info->state & (1<<MD_DISK_SYNC)  &&
2217                             info->raid_disk < mddev->raid_disks)
2218                                 rdev->raid_disk = info->raid_disk;
2219                         else
2220                                 rdev->raid_disk = -1;
2221                 } else
2222                         super_types[mddev->major_version].
2223                                 validate_super(mddev, rdev);
2224                 rdev->saved_raid_disk = rdev->raid_disk;
2225
2226                 rdev->in_sync = 0; /* just to be sure */
2227                 rdev->raid_disk = -1;
2228                 err = bind_rdev_to_array(rdev, mddev);
2229                 if (err)
2230                         export_rdev(rdev);
2231
2232                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2233                 if (mddev->thread)
2234                         md_wakeup_thread(mddev->thread);
2235                 return err;
2236         }
2237
2238         /* otherwise, add_new_disk is only allowed
2239          * for major_version==0 superblocks
2240          */
2241         if (mddev->major_version != 0) {
2242                 printk(KERN_WARNING "%s: ADD_NEW_DISK not supported\n",
2243                        mdname(mddev));
2244                 return -EINVAL;
2245         }
2246
2247         if (!(info->state & (1<<MD_DISK_FAULTY))) {
2248                 int err;
2249                 rdev = md_import_device (dev, -1, 0);
2250                 if (IS_ERR(rdev)) {
2251                         printk(KERN_WARNING
2252                                 "md: error, md_import_device() returned %ld\n",
2253                                 PTR_ERR(rdev));
2254                         return PTR_ERR(rdev);
2255                 }
2256                 rdev->desc_nr = info->number;
2257                 if (info->raid_disk < mddev->raid_disks)
2258                         rdev->raid_disk = info->raid_disk;
2259                 else
2260                         rdev->raid_disk = -1;
2261
2262                 rdev->faulty = 0;
2263                 if (rdev->raid_disk < mddev->raid_disks)
2264                         rdev->in_sync = (info->state & (1<<MD_DISK_SYNC));
2265                 else
2266                         rdev->in_sync = 0;
2267
2268                 err = bind_rdev_to_array(rdev, mddev);
2269                 if (err) {
2270                         export_rdev(rdev);
2271                         return err;
2272                 }
2273
2274                 if (!mddev->persistent) {
2275                         printk(KERN_INFO "md: nonpersistent superblock ...\n");
2276                         rdev->sb_offset = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
2277                 } else
2278                         rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
2279                 rdev->size = calc_dev_size(rdev, mddev->chunk_size);
2280
2281                 if (!mddev->size || (mddev->size > rdev->size))
2282                         mddev->size = rdev->size;
2283         }
2284
2285         return 0;
2286 }
2287
2288 static int hot_remove_disk(mddev_t * mddev, dev_t dev)
2289 {
2290         char b[BDEVNAME_SIZE];
2291         mdk_rdev_t *rdev;
2292
2293         if (!mddev->pers)
2294                 return -ENODEV;
2295
2296         rdev = find_rdev(mddev, dev);
2297         if (!rdev)
2298                 return -ENXIO;
2299
2300         if (rdev->raid_disk >= 0)
2301                 goto busy;
2302
2303         kick_rdev_from_array(rdev);
2304         md_update_sb(mddev);
2305
2306         return 0;
2307 busy:
2308         printk(KERN_WARNING "md: cannot remove active disk %s from %s ... \n",
2309                 bdevname(rdev->bdev,b), mdname(mddev));
2310         return -EBUSY;
2311 }
2312
2313 static int hot_add_disk(mddev_t * mddev, dev_t dev)
2314 {
2315         char b[BDEVNAME_SIZE];
2316         int err;
2317         unsigned int size;
2318         mdk_rdev_t *rdev;
2319
2320         if (!mddev->pers)
2321                 return -ENODEV;
2322
2323         if (mddev->major_version != 0) {
2324                 printk(KERN_WARNING "%s: HOT_ADD may only be used with"
2325                         " version-0 superblocks.\n",
2326                         mdname(mddev));
2327                 return -EINVAL;
2328         }
2329         if (!mddev->pers->hot_add_disk) {
2330                 printk(KERN_WARNING
2331                         "%s: personality does not support diskops!\n",
2332                         mdname(mddev));
2333                 return -EINVAL;
2334         }
2335
2336         rdev = md_import_device (dev, -1, 0);
2337         if (IS_ERR(rdev)) {
2338                 printk(KERN_WARNING
2339                         "md: error, md_import_device() returned %ld\n",
2340                         PTR_ERR(rdev));
2341                 return -EINVAL;
2342         }
2343
2344         if (mddev->persistent)
2345                 rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
2346         else
2347                 rdev->sb_offset =
2348                         rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
2349
2350         size = calc_dev_size(rdev, mddev->chunk_size);
2351         rdev->size = size;
2352
2353         if (size < mddev->size) {
2354                 printk(KERN_WARNING
2355                         "%s: disk size %llu blocks < array size %llu\n",
2356                         mdname(mddev), (unsigned long long)size,
2357                         (unsigned long long)mddev->size);
2358                 err = -ENOSPC;
2359                 goto abort_export;
2360         }
2361
2362         if (rdev->faulty) {
2363                 printk(KERN_WARNING
2364                         "md: can not hot-add faulty %s disk to %s!\n",
2365                         bdevname(rdev->bdev,b), mdname(mddev));
2366                 err = -EINVAL;
2367                 goto abort_export;
2368         }
2369         rdev->in_sync = 0;
2370         rdev->desc_nr = -1;
2371         bind_rdev_to_array(rdev, mddev);
2372
2373         /*
2374          * The rest should better be atomic, we can have disk failures
2375          * noticed in interrupt contexts ...
2376          */
2377
2378         if (rdev->desc_nr == mddev->max_disks) {
2379                 printk(KERN_WARNING "%s: can not hot-add to full array!\n",
2380                         mdname(mddev));
2381                 err = -EBUSY;
2382                 goto abort_unbind_export;
2383         }
2384
2385         rdev->raid_disk = -1;
2386
2387         md_update_sb(mddev);
2388
2389         /*
2390          * Kick recovery, maybe this spare has to be added to the
2391          * array immediately.
2392          */
2393         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2394         md_wakeup_thread(mddev->thread);
2395
2396         return 0;
2397
2398 abort_unbind_export:
2399         unbind_rdev_from_array(rdev);
2400
2401 abort_export:
2402         export_rdev(rdev);
2403         return err;
2404 }
2405
2406 /* similar to deny_write_access, but accounts for our holding a reference
2407  * to the file ourselves */
2408 static int deny_bitmap_write_access(struct file * file)
2409 {
2410         struct inode *inode = file->f_mapping->host;
2411
2412         spin_lock(&inode->i_lock);
2413         if (atomic_read(&inode->i_writecount) > 1) {
2414                 spin_unlock(&inode->i_lock);
2415                 return -ETXTBSY;
2416         }
2417         atomic_set(&inode->i_writecount, -1);
2418         spin_unlock(&inode->i_lock);
2419
2420         return 0;
2421 }
2422
2423 static int set_bitmap_file(mddev_t *mddev, int fd)
2424 {
2425         int err;
2426
2427         if (mddev->pers)
2428                 return -EBUSY;
2429
2430         mddev->bitmap_file = fget(fd);
2431
2432         if (mddev->bitmap_file == NULL) {
2433                 printk(KERN_ERR "%s: error: failed to get bitmap file\n",
2434                         mdname(mddev));
2435                 return -EBADF;
2436         }
2437
2438         err = deny_bitmap_write_access(mddev->bitmap_file);
2439         if (err) {
2440                 printk(KERN_ERR "%s: error: bitmap file is already in use\n",
2441                         mdname(mddev));
2442                 fput(mddev->bitmap_file);
2443                 mddev->bitmap_file = NULL;
2444         } else
2445                 mddev->bitmap_offset = 0; /* file overrides offset */
2446         return err;
2447 }
2448
2449 /*
2450  * set_array_info is used two different ways
2451  * The original usage is when creating a new array.
2452  * In this usage, raid_disks is > 0 and it together with
2453  *  level, size, not_persistent,layout,chunksize determine the
2454  *  shape of the array.
2455  *  This will always create an array with a type-0.90.0 superblock.
2456  * The newer usage is when assembling an array.
2457  *  In this case raid_disks will be 0, and the major_version field is
2458  *  use to determine which style super-blocks are to be found on the devices.
2459  *  The minor and patch _version numbers are also kept incase the
2460  *  super_block handler wishes to interpret them.
2461  */
2462 static int set_array_info(mddev_t * mddev, mdu_array_info_t *info)
2463 {
2464
2465         if (info->raid_disks == 0) {
2466                 /* just setting version number for superblock loading */
2467                 if (info->major_version < 0 ||
2468                     info->major_version >= sizeof(super_types)/sizeof(super_types[0]) ||
2469                     super_types[info->major_version].name == NULL) {
2470                         /* maybe try to auto-load a module? */
2471                         printk(KERN_INFO
2472                                 "md: superblock version %d not known\n",
2473                                 info->major_version);
2474                         return -EINVAL;
2475                 }
2476                 mddev->major_version = info->major_version;
2477                 mddev->minor_version = info->minor_version;
2478                 mddev->patch_version = info->patch_version;
2479                 return 0;
2480         }
2481         mddev->major_version = MD_MAJOR_VERSION;
2482         mddev->minor_version = MD_MINOR_VERSION;
2483         mddev->patch_version = MD_PATCHLEVEL_VERSION;
2484         mddev->ctime         = get_seconds();
2485
2486         mddev->level         = info->level;
2487         mddev->size          = info->size;
2488         mddev->raid_disks    = info->raid_disks;
2489         /* don't set md_minor, it is determined by which /dev/md* was
2490          * openned
2491          */
2492         if (info->state & (1<<MD_SB_CLEAN))
2493                 mddev->recovery_cp = MaxSector;
2494         else
2495                 mddev->recovery_cp = 0;
2496         mddev->persistent    = ! info->not_persistent;
2497
2498         mddev->layout        = info->layout;
2499         mddev->chunk_size    = info->chunk_size;
2500
2501         mddev->max_disks     = MD_SB_DISKS;
2502
2503         mddev->sb_dirty      = 1;
2504
2505         /*
2506          * Generate a 128 bit UUID
2507          */
2508         get_random_bytes(mddev->uuid, 16);
2509
2510         return 0;
2511 }
2512
2513 /*
2514  * update_array_info is used to change the configuration of an
2515  * on-line array.
2516  * The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
2517  * fields in the info are checked against the array.
2518  * Any differences that cannot be handled will cause an error.
2519  * Normally, only one change can be managed at a time.
2520  */
2521 static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
2522 {
2523         int rv = 0;
2524         int cnt = 0;
2525
2526         if (mddev->major_version != info->major_version ||
2527             mddev->minor_version != info->minor_version ||
2528 /*          mddev->patch_version != info->patch_version || */
2529             mddev->ctime         != info->ctime         ||
2530             mddev->level         != info->level         ||
2531 /*          mddev->layout        != info->layout        || */
2532             !mddev->persistent   != info->not_persistent||
2533             mddev->chunk_size    != info->chunk_size    )
2534                 return -EINVAL;
2535         /* Check there is only one change */
2536         if (mddev->size != info->size) cnt++;
2537         if (mddev->raid_disks != info->raid_disks) cnt++;
2538         if (mddev->layout != info->layout) cnt++;
2539         if (cnt == 0) return 0;
2540         if (cnt > 1) return -EINVAL;
2541
2542         if (mddev->layout != info->layout) {
2543                 /* Change layout
2544                  * we don't need to do anything at the md level, the
2545                  * personality will take care of it all.
2546                  */
2547                 if (mddev->pers->reconfig == NULL)
2548                         return -EINVAL;
2549                 else
2550                         return mddev->pers->reconfig(mddev, info->layout, -1);
2551         }
2552         if (mddev->size != info->size) {
2553                 mdk_rdev_t * rdev;
2554                 struct list_head *tmp;
2555                 if (mddev->pers->resize == NULL)
2556                         return -EINVAL;
2557                 /* The "size" is the amount of each device that is used.
2558                  * This can only make sense for arrays with redundancy.
2559                  * linear and raid0 always use whatever space is available
2560                  * We can only consider changing the size if no resync
2561                  * or reconstruction is happening, and if the new size
2562                  * is acceptable. It must fit before the sb_offset or,
2563                  * if that is <data_offset, it must fit before the
2564                  * size of each device.
2565                  * If size is zero, we find the largest size that fits.
2566                  */
2567                 if (mddev->sync_thread)
2568                         return -EBUSY;
2569                 ITERATE_RDEV(mddev,rdev,tmp) {
2570                         sector_t avail;
2571                         int fit = (info->size == 0);
2572                         if (rdev->sb_offset > rdev->data_offset)
2573                                 avail = (rdev->sb_offset*2) - rdev->data_offset;
2574                         else
2575                                 avail = get_capacity(rdev->bdev->bd_disk)
2576                                         - rdev->data_offset;
2577                         if (fit && (info->size == 0 || info->size > avail/2))
2578                                 info->size = avail/2;
2579                         if (avail < ((sector_t)info->size << 1))
2580                                 return -ENOSPC;
2581                 }
2582                 rv = mddev->pers->resize(mddev, (sector_t)info->size *2);
2583                 if (!rv) {
2584                         struct block_device *bdev;
2585
2586                         bdev = bdget_disk(mddev->gendisk, 0);
2587                         if (bdev) {
2588                                 down(&bdev->bd_inode->i_sem);
2589                                 i_size_write(bdev->bd_inode, mddev->array_size << 10);
2590                                 up(&bdev->bd_inode->i_sem);
2591                                 bdput(bdev);
2592                         }
2593                 }
2594         }
2595         if (mddev->raid_disks    != info->raid_disks) {
2596                 /* change the number of raid disks */
2597                 if (mddev->pers->reshape == NULL)
2598                         return -EINVAL;
2599                 if (info->raid_disks <= 0 ||
2600                     info->raid_disks >= mddev->max_disks)
2601                         return -EINVAL;
2602                 if (mddev->sync_thread)
2603                         return -EBUSY;
2604                 rv = mddev->pers->reshape(mddev, info->raid_disks);
2605                 if (!rv) {
2606                         struct block_device *bdev;
2607
2608                         bdev = bdget_disk(mddev->gendisk, 0);
2609                         if (bdev) {
2610                                 down(&bdev->bd_inode->i_sem);
2611                                 i_size_write(bdev->bd_inode, mddev->array_size << 10);
2612                                 up(&bdev->bd_inode->i_sem);
2613                                 bdput(bdev);
2614                         }
2615                 }
2616         }
2617         md_update_sb(mddev);
2618         return rv;
2619 }
2620
2621 static int set_disk_faulty(mddev_t *mddev, dev_t dev)
2622 {
2623         mdk_rdev_t *rdev;
2624
2625         if (mddev->pers == NULL)
2626                 return -ENODEV;
2627
2628         rdev = find_rdev(mddev, dev);
2629         if (!rdev)
2630                 return -ENODEV;
2631
2632         md_error(mddev, rdev);
2633         return 0;
2634 }
2635
2636 static int md_ioctl(struct inode *inode, struct file *file,
2637                         unsigned int cmd, unsigned long arg)
2638 {
2639         int err = 0;
2640         void __user *argp = (void __user *)arg;
2641         struct hd_geometry __user *loc = argp;
2642         mddev_t *mddev = NULL;
2643
2644         if (!capable(CAP_SYS_ADMIN))
2645                 return -EACCES;
2646
2647         /*
2648          * Commands dealing with the RAID driver but not any
2649          * particular array:
2650          */
2651         switch (cmd)
2652         {
2653                 case RAID_VERSION:
2654                         err = get_version(argp);
2655                         goto done;
2656
2657                 case PRINT_RAID_DEBUG:
2658                         err = 0;
2659                         md_print_devices();
2660                         goto done;
2661
2662 #ifndef MODULE
2663                 case RAID_AUTORUN:
2664                         err = 0;
2665                         autostart_arrays(arg);
2666                         goto done;
2667 #endif
2668                 default:;
2669         }
2670
2671         /*
2672          * Commands creating/starting a new array:
2673          */
2674
2675         mddev = inode->i_bdev->bd_disk->private_data;
2676
2677         if (!mddev) {
2678                 BUG();
2679                 goto abort;
2680         }
2681
2682
2683         if (cmd == START_ARRAY) {
2684                 /* START_ARRAY doesn't need to lock the array as autostart_array
2685                  * does the locking, and it could even be a different array
2686                  */
2687                 static int cnt = 3;
2688                 if (cnt > 0 ) {
2689                         printk(KERN_WARNING
2690                                "md: %s(pid %d) used deprecated START_ARRAY ioctl. "
2691                                "This will not be supported beyond 2.6\n",
2692                                current->comm, current->pid);
2693                         cnt--;
2694                 }
2695                 err = autostart_array(new_decode_dev(arg));
2696                 if (err) {
2697                         printk(KERN_WARNING "md: autostart failed!\n");
2698                         goto abort;
2699                 }
2700                 goto done;
2701         }
2702
2703         err = mddev_lock(mddev);
2704         if (err) {
2705                 printk(KERN_INFO
2706                         "md: ioctl lock interrupted, reason %d, cmd %d\n",
2707                         err, cmd);
2708                 goto abort;
2709         }
2710
2711         switch (cmd)
2712         {
2713                 case SET_ARRAY_INFO:
2714                         {
2715                                 mdu_array_info_t info;
2716                                 if (!arg)
2717                                         memset(&info, 0, sizeof(info));
2718                                 else if (copy_from_user(&info, argp, sizeof(info))) {
2719                                         err = -EFAULT;
2720                                         goto abort_unlock;
2721                                 }
2722                                 if (mddev->pers) {
2723                                         err = update_array_info(mddev, &info);
2724                                         if (err) {
2725                                                 printk(KERN_WARNING "md: couldn't update"
2726                                                        " array info. %d\n", err);
2727                                                 goto abort_unlock;
2728                                         }
2729                                         goto done_unlock;
2730                                 }
2731                                 if (!list_empty(&mddev->disks)) {
2732                                         printk(KERN_WARNING
2733                                                "md: array %s already has disks!\n",
2734                                                mdname(mddev));
2735                                         err = -EBUSY;
2736                                         goto abort_unlock;
2737                                 }
2738                                 if (mddev->raid_disks) {
2739                                         printk(KERN_WARNING
2740                                                "md: array %s already initialised!\n",
2741                                                mdname(mddev));
2742                                         err = -EBUSY;
2743                                         goto abort_unlock;
2744                                 }
2745                                 err = set_array_info(mddev, &info);
2746                                 if (err) {
2747                                         printk(KERN_WARNING "md: couldn't set"
2748                                                " array info. %d\n", err);
2749                                         goto abort_unlock;
2750                                 }
2751                         }
2752                         goto done_unlock;
2753
2754                 default:;
2755         }
2756
2757         /*
2758          * Commands querying/configuring an existing array:
2759          */
2760         /* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
2761          * RUN_ARRAY, and SET_BITMAP_FILE are allowed */
2762         if (!mddev->raid_disks && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
2763                         && cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE) {
2764                 err = -ENODEV;
2765                 goto abort_unlock;
2766         }
2767
2768         /*
2769          * Commands even a read-only array can execute:
2770          */
2771         switch (cmd)
2772         {
2773                 case GET_ARRAY_INFO:
2774                         err = get_array_info(mddev, argp);
2775                         goto done_unlock;
2776
2777                 case GET_BITMAP_FILE:
2778                         err = get_bitmap_file(mddev, (void *)arg);
2779                         goto done_unlock;
2780
2781                 case GET_DISK_INFO:
2782                         err = get_disk_info(mddev, argp);
2783                         goto done_unlock;
2784
2785                 case RESTART_ARRAY_RW:
2786                         err = restart_array(mddev);
2787                         goto done_unlock;
2788
2789                 case STOP_ARRAY:
2790                         err = do_md_stop (mddev, 0);
2791                         goto done_unlock;
2792
2793                 case STOP_ARRAY_RO:
2794                         err = do_md_stop (mddev, 1);
2795                         goto done_unlock;
2796
2797         /*
2798          * We have a problem here : there is no easy way to give a CHS
2799          * virtual geometry. We currently pretend that we have a 2 heads
2800          * 4 sectors (with a BIG number of cylinders...). This drives
2801          * dosfs just mad... ;-)
2802          */
2803                 case HDIO_GETGEO:
2804                         if (!loc) {
2805                                 err = -EINVAL;
2806                                 goto abort_unlock;
2807                         }
2808                         err = put_user (2, (char __user *) &loc->heads);
2809                         if (err)
2810                                 goto abort_unlock;
2811                         err = put_user (4, (char __user *) &loc->sectors);
2812                         if (err)
2813                                 goto abort_unlock;
2814                         err = put_user(get_capacity(mddev->gendisk)/8,
2815                                         (short __user *) &loc->cylinders);
2816                         if (err)
2817                                 goto abort_unlock;
2818                         err = put_user (get_start_sect(inode->i_bdev),
2819                                                 (long __user *) &loc->start);
2820                         goto done_unlock;
2821         }
2822
2823         /*
2824          * The remaining ioctls are changing the state of the
2825          * superblock, so we do not allow read-only arrays
2826          * here:
2827          */
2828         if (mddev->ro) {
2829                 err = -EROFS;
2830                 goto abort_unlock;
2831         }
2832
2833         switch (cmd)
2834         {
2835                 case ADD_NEW_DISK:
2836                 {
2837                         mdu_disk_info_t info;
2838                         if (copy_from_user(&info, argp, sizeof(info)))
2839                                 err = -EFAULT;
2840                         else
2841                                 err = add_new_disk(mddev, &info);
2842                         goto done_unlock;
2843                 }
2844
2845                 case HOT_REMOVE_DISK:
2846                         err = hot_remove_disk(mddev, new_decode_dev(arg));
2847                         goto done_unlock;
2848
2849                 case HOT_ADD_DISK:
2850                         err = hot_add_disk(mddev, new_decode_dev(arg));
2851                         goto done_unlock;
2852
2853                 case SET_DISK_FAULTY:
2854                         err = set_disk_faulty(mddev, new_decode_dev(arg));
2855                         goto done_unlock;
2856
2857                 case RUN_ARRAY:
2858                         err = do_md_run (mddev);
2859                         goto done_unlock;
2860
2861                 case SET_BITMAP_FILE:
2862                         err = set_bitmap_file(mddev, (int)arg);
2863                         goto done_unlock;
2864
2865                 default:
2866                         if (_IOC_TYPE(cmd) == MD_MAJOR)
2867                                 printk(KERN_WARNING "md: %s(pid %d) used"
2868                                         " obsolete MD ioctl, upgrade your"
2869                                         " software to use new ictls.\n",
2870                                         current->comm, current->pid);
2871                         err = -EINVAL;
2872                         goto abort_unlock;
2873         }
2874
2875 done_unlock:
2876 abort_unlock:
2877         mddev_unlock(mddev);
2878
2879         return err;
2880 done:
2881         if (err)
2882                 MD_BUG();
2883 abort:
2884         return err;
2885 }
2886
2887 static int md_open(struct inode *inode, struct file *file)
2888 {
2889         /*
2890          * Succeed if we can lock the mddev, which confirms that
2891          * it isn't being stopped right now.
2892          */
2893         mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
2894         int err;
2895
2896         if ((err = mddev_lock(mddev)))
2897                 goto out;
2898
2899         err = 0;
2900         mddev_get(mddev);
2901         mddev_unlock(mddev);
2902
2903         check_disk_change(inode->i_bdev);
2904  out:
2905         return err;
2906 }
2907
2908 static int md_release(struct inode *inode, struct file * file)
2909 {
2910         mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
2911
2912         if (!mddev)
2913                 BUG();
2914         mddev_put(mddev);
2915
2916         return 0;
2917 }
2918
2919 static int md_media_changed(struct gendisk *disk)
2920 {
2921         mddev_t *mddev = disk->private_data;
2922
2923         return mddev->changed;
2924 }
2925
2926 static int md_revalidate(struct gendisk *disk)
2927 {
2928         mddev_t *mddev = disk->private_data;
2929
2930         mddev->changed = 0;
2931         return 0;
2932 }
2933 static struct block_device_operations md_fops =
2934 {
2935         .owner          = THIS_MODULE,
2936         .open           = md_open,
2937         .release        = md_release,
2938         .ioctl          = md_ioctl,
2939         .media_changed  = md_media_changed,
2940         .revalidate_disk= md_revalidate,
2941 };
2942
2943 static int md_thread(void * arg)
2944 {
2945         mdk_thread_t *thread = arg;
2946
2947         lock_kernel();
2948
2949         /*
2950          * Detach thread
2951          */
2952
2953         daemonize(thread->name, mdname(thread->mddev));
2954
2955         current->exit_signal = SIGCHLD;
2956         allow_signal(SIGKILL);
2957         thread->tsk = current;
2958
2959         /*
2960          * md_thread is a 'system-thread', it's priority should be very
2961          * high. We avoid resource deadlocks individually in each
2962          * raid personality. (RAID5 does preallocation) We also use RR and
2963          * the very same RT priority as kswapd, thus we will never get
2964          * into a priority inversion deadlock.
2965          *
2966          * we definitely have to have equal or higher priority than
2967          * bdflush, otherwise bdflush will deadlock if there are too
2968          * many dirty RAID5 blocks.
2969          */
2970         unlock_kernel();
2971
2972         complete(thread->event);
2973         while (thread->run) {
2974                 void (*run)(mddev_t *);
2975
2976                 wait_event_interruptible_timeout(thread->wqueue,
2977                                                  test_bit(THREAD_WAKEUP, &thread->flags),
2978                                                  thread->timeout);
2979                 try_to_freeze();
2980
2981                 clear_bit(THREAD_WAKEUP, &thread->flags);
2982
2983                 run = thread->run;
2984                 if (run)
2985                         run(thread->mddev);
2986
2987                 if (signal_pending(current))
2988                         flush_signals(current);
2989         }
2990         complete(thread->event);
2991         return 0;
2992 }
2993
2994 void md_wakeup_thread(mdk_thread_t *thread)
2995 {
2996         if (thread) {
2997                 dprintk("md: waking up MD thread %s.\n", thread->tsk->comm);
2998                 set_bit(THREAD_WAKEUP, &thread->flags);
2999                 wake_up(&thread->wqueue);
3000         }
3001 }
3002
3003 mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev,
3004                                  const char *name)
3005 {
3006         mdk_thread_t *thread;
3007         int ret;
3008         struct completion event;
3009
3010         thread = (mdk_thread_t *) kmalloc
3011                                 (sizeof(mdk_thread_t), GFP_KERNEL);
3012         if (!thread)
3013                 return NULL;
3014
3015         memset(thread, 0, sizeof(mdk_thread_t));
3016         init_waitqueue_head(&thread->wqueue);
3017
3018         init_completion(&event);
3019         thread->event = &event;
3020         thread->run = run;
3021         thread->mddev = mddev;
3022         thread->name = name;
3023         thread->timeout = MAX_SCHEDULE_TIMEOUT;
3024         ret = kernel_thread(md_thread, thread, 0);
3025         if (ret < 0) {
3026                 kfree(thread);
3027                 return NULL;
3028         }
3029         wait_for_completion(&event);
3030         return thread;
3031 }
3032
3033 void md_unregister_thread(mdk_thread_t *thread)
3034 {
3035         struct completion event;
3036
3037         init_completion(&event);
3038
3039         thread->event = &event;
3040
3041         /* As soon as ->run is set to NULL, the task could disappear,
3042          * so we need to hold tasklist_lock until we have sent the signal
3043          */
3044         dprintk("interrupting MD-thread pid %d\n", thread->tsk->pid);
3045         read_lock(&tasklist_lock);
3046         thread->run = NULL;
3047         send_sig(SIGKILL, thread->tsk, 1);
3048         read_unlock(&tasklist_lock);
3049         wait_for_completion(&event);
3050         kfree(thread);
3051 }
3052
3053 void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
3054 {
3055         if (!mddev) {
3056                 MD_BUG();
3057                 return;
3058         }
3059
3060         if (!rdev || rdev->faulty)
3061                 return;
3062 /*
3063         dprintk("md_error dev:%s, rdev:(%d:%d), (caller: %p,%p,%p,%p).\n",
3064                 mdname(mddev),
3065                 MAJOR(rdev->bdev->bd_dev), MINOR(rdev->bdev->bd_dev),
3066                 __builtin_return_address(0),__builtin_return_address(1),
3067                 __builtin_return_address(2),__builtin_return_address(3));
3068 */
3069         if (!mddev->pers->error_handler)
3070                 return;
3071         mddev->pers->error_handler(mddev,rdev);
3072         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3073         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3074         md_wakeup_thread(mddev->thread);
3075 }
3076
3077 /* seq_file implementation /proc/mdstat */
3078
3079 static void status_unused(struct seq_file *seq)
3080 {
3081         int i = 0;
3082         mdk_rdev_t *rdev;
3083         struct list_head *tmp;
3084
3085         seq_printf(seq, "unused devices: ");
3086
3087         ITERATE_RDEV_PENDING(rdev,tmp) {
3088                 char b[BDEVNAME_SIZE];
3089                 i++;
3090                 seq_printf(seq, "%s ",
3091                               bdevname(rdev->bdev,b));
3092         }
3093         if (!i)
3094                 seq_printf(seq, "<none>");
3095
3096         seq_printf(seq, "\n");
3097 }
3098
3099
3100 static void status_resync(struct seq_file *seq, mddev_t * mddev)
3101 {
3102         unsigned long max_blocks, resync, res, dt, db, rt;
3103
3104         resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active))/2;
3105
3106         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
3107                 max_blocks = mddev->resync_max_sectors >> 1;
3108         else
3109                 max_blocks = mddev->size;
3110
3111         /*
3112          * Should not happen.
3113          */
3114         if (!max_blocks) {
3115                 MD_BUG();
3116                 return;
3117         }
3118         res = (resync/1024)*1000/(max_blocks/1024 + 1);
3119         {
3120                 int i, x = res/50, y = 20-x;
3121                 seq_printf(seq, "[");
3122                 for (i = 0; i < x; i++)
3123                         seq_printf(seq, "=");
3124                 seq_printf(seq, ">");
3125                 for (i = 0; i < y; i++)
3126                         seq_printf(seq, ".");
3127                 seq_printf(seq, "] ");
3128         }
3129         seq_printf(seq, " %s =%3lu.%lu%% (%lu/%lu)",
3130                       (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
3131                        "resync" : "recovery"),
3132                       res/10, res % 10, resync, max_blocks);
3133
3134         /*
3135          * We do not want to overflow, so the order of operands and
3136          * the * 100 / 100 trick are important. We do a +1 to be
3137          * safe against division by zero. We only estimate anyway.
3138          *
3139          * dt: time from mark until now
3140          * db: blocks written from mark until now
3141          * rt: remaining time
3142          */
3143         dt = ((jiffies - mddev->resync_mark) / HZ);
3144         if (!dt) dt++;
3145         db = resync - (mddev->resync_mark_cnt/2);
3146         rt = (dt * ((max_blocks-resync) / (db/100+1)))/100;
3147
3148         seq_printf(seq, " finish=%lu.%lumin", rt / 60, (rt % 60)/6);
3149
3150         seq_printf(seq, " speed=%ldK/sec", db/dt);
3151 }
3152
3153 static void *md_seq_start(struct seq_file *seq, loff_t *pos)
3154 {
3155         struct list_head *tmp;
3156         loff_t l = *pos;
3157         mddev_t *mddev;
3158
3159         if (l >= 0x10000)
3160                 return NULL;
3161         if (!l--)
3162                 /* header */
3163                 return (void*)1;
3164
3165         spin_lock(&all_mddevs_lock);
3166         list_for_each(tmp,&all_mddevs)
3167                 if (!l--) {
3168                         mddev = list_entry(tmp, mddev_t, all_mddevs);
3169                         mddev_get(mddev);
3170                         spin_unlock(&all_mddevs_lock);
3171                         return mddev;
3172                 }
3173         spin_unlock(&all_mddevs_lock);
3174         if (!l--)
3175                 return (void*)2;/* tail */
3176         return NULL;
3177 }
3178
3179 static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3180 {
3181         struct list_head *tmp;
3182         mddev_t *next_mddev, *mddev = v;
3183
3184         ++*pos;
3185         if (v == (void*)2)
3186                 return NULL;
3187
3188         spin_lock(&all_mddevs_lock);
3189         if (v == (void*)1)
3190                 tmp = all_mddevs.next;
3191         else
3192                 tmp = mddev->all_mddevs.next;
3193         if (tmp != &all_mddevs)
3194                 next_mddev = mddev_get(list_entry(tmp,mddev_t,all_mddevs));
3195         else {
3196                 next_mddev = (void*)2;
3197                 *pos = 0x10000;
3198         }
3199         spin_unlock(&all_mddevs_lock);
3200
3201         if (v != (void*)1)
3202                 mddev_put(mddev);
3203         return next_mddev;
3204
3205 }
3206
3207 static void md_seq_stop(struct seq_file *seq, void *v)
3208 {
3209         mddev_t *mddev = v;
3210
3211         if (mddev && v != (void*)1 && v != (void*)2)
3212                 mddev_put(mddev);
3213 }
3214
3215 static int md_seq_show(struct seq_file *seq, void *v)
3216 {
3217         mddev_t *mddev = v;
3218         sector_t size;
3219         struct list_head *tmp2;
3220         mdk_rdev_t *rdev;
3221         int i;
3222         struct bitmap *bitmap;
3223
3224         if (v == (void*)1) {
3225                 seq_printf(seq, "Personalities : ");
3226                 spin_lock(&pers_lock);
3227                 for (i = 0; i < MAX_PERSONALITY; i++)
3228                         if (pers[i])
3229                                 seq_printf(seq, "[%s] ", pers[i]->name);
3230
3231                 spin_unlock(&pers_lock);
3232                 seq_printf(seq, "\n");
3233                 return 0;
3234         }
3235         if (v == (void*)2) {
3236                 status_unused(seq);
3237                 return 0;
3238         }
3239
3240         if (mddev_lock(mddev)!=0)
3241                 return -EINTR;
3242         if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
3243                 seq_printf(seq, "%s : %sactive", mdname(mddev),
3244                                                 mddev->pers ? "" : "in");
3245                 if (mddev->pers) {
3246                         if (mddev->ro)
3247                                 seq_printf(seq, " (read-only)");
3248                         seq_printf(seq, " %s", mddev->pers->name);
3249                 }
3250
3251                 size = 0;
3252                 ITERATE_RDEV(mddev,rdev,tmp2) {
3253                         char b[BDEVNAME_SIZE];
3254                         seq_printf(seq, " %s[%d]",
3255                                 bdevname(rdev->bdev,b), rdev->desc_nr);
3256                         if (rdev->faulty) {
3257                                 seq_printf(seq, "(F)");
3258                                 continue;
3259                         }
3260                         size += rdev->size;
3261                 }
3262
3263                 if (!list_empty(&mddev->disks)) {
3264                         if (mddev->pers)
3265                                 seq_printf(seq, "\n      %llu blocks",
3266                                         (unsigned long long)mddev->array_size);
3267                         else
3268                                 seq_printf(seq, "\n      %llu blocks",
3269                                         (unsigned long long)size);
3270                 }
3271
3272                 if (mddev->pers) {
3273                         mddev->pers->status (seq, mddev);
3274                         seq_printf(seq, "\n      ");
3275                         if (mddev->curr_resync > 2) {
3276                                 status_resync (seq, mddev);
3277                                 seq_printf(seq, "\n      ");
3278                         } else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
3279                                 seq_printf(seq, "       resync=DELAYED\n      ");
3280                 } else
3281                         seq_printf(seq, "\n       ");
3282
3283                 if ((bitmap = mddev->bitmap)) {
3284                         unsigned long chunk_kb;
3285                         unsigned long flags;
3286                         spin_lock_irqsave(&bitmap->lock, flags);
3287                         chunk_kb = bitmap->chunksize >> 10;
3288                         seq_printf(seq, "bitmap: %lu/%lu pages [%luKB], "
3289                                 "%lu%s chunk",
3290                                 bitmap->pages - bitmap->missing_pages,
3291                                 bitmap->pages,
3292                                 (bitmap->pages - bitmap->missing_pages)
3293                                         << (PAGE_SHIFT - 10),
3294                                 chunk_kb ? chunk_kb : bitmap->chunksize,
3295                                 chunk_kb ? "KB" : "B");
3296                         if (bitmap->file) {
3297                                 seq_printf(seq, ", file: ");
3298                                 seq_path(seq, bitmap->file->f_vfsmnt,
3299                                          bitmap->file->f_dentry," \t\n");
3300                         }
3301
3302                         seq_printf(seq, "\n");
3303                         spin_unlock_irqrestore(&bitmap->lock, flags);
3304                 }
3305
3306                 seq_printf(seq, "\n");
3307         }
3308         mddev_unlock(mddev);
3309
3310         return 0;
3311 }
3312
3313 static struct seq_operations md_seq_ops = {
3314         .start  = md_seq_start,
3315         .next   = md_seq_next,
3316         .stop   = md_seq_stop,
3317         .show   = md_seq_show,
3318 };
3319
3320 static int md_seq_open(struct inode *inode, struct file *file)
3321 {
3322         int error;
3323
3324         error = seq_open(file, &md_seq_ops);
3325         return error;
3326 }
3327
3328 static struct file_operations md_seq_fops = {
3329         .open           = md_seq_open,
3330         .read           = seq_read,
3331         .llseek         = seq_lseek,
3332         .release        = seq_release,
3333 };
3334
3335 int register_md_personality(int pnum, mdk_personality_t *p)
3336 {
3337         if (pnum >= MAX_PERSONALITY) {
3338                 printk(KERN_ERR
3339                        "md: tried to install personality %s as nr %d, but max is %lu\n",
3340                        p->name, pnum, MAX_PERSONALITY-1);
3341                 return -EINVAL;
3342         }
3343
3344         spin_lock(&pers_lock);
3345         if (pers[pnum]) {
3346                 spin_unlock(&pers_lock);
3347                 return -EBUSY;
3348         }
3349
3350         pers[pnum] = p;
3351         printk(KERN_INFO "md: %s personality registered as nr %d\n", p->name, pnum);
3352         spin_unlock(&pers_lock);
3353         return 0;
3354 }
3355
3356 int unregister_md_personality(int pnum)
3357 {
3358         if (pnum >= MAX_PERSONALITY)
3359                 return -EINVAL;
3360
3361         printk(KERN_INFO "md: %s personality unregistered\n", pers[pnum]->name);
3362         spin_lock(&pers_lock);
3363         pers[pnum] = NULL;
3364         spin_unlock(&pers_lock);
3365         return 0;
3366 }
3367
3368 static int is_mddev_idle(mddev_t *mddev)
3369 {
3370         mdk_rdev_t * rdev;
3371         struct list_head *tmp;
3372         int idle;
3373         unsigned long curr_events;
3374
3375         idle = 1;
3376         ITERATE_RDEV(mddev,rdev,tmp) {
3377                 struct gendisk *disk = rdev->bdev->bd_contains->bd_disk;
3378                 curr_events = disk_stat_read(disk, read_sectors) +
3379                                 disk_stat_read(disk, write_sectors) -
3380                                 atomic_read(&disk->sync_io);
3381                 /* Allow some slack between valud of curr_events and last_events,
3382                  * as there are some uninteresting races.
3383                  * Note: the following is an unsigned comparison.
3384                  */
3385                 if ((curr_events - rdev->last_events + 32) > 64) {
3386                         rdev->last_events = curr_events;
3387                         idle = 0;
3388                 }
3389         }
3390         return idle;
3391 }
3392
3393 void md_done_sync(mddev_t *mddev, int blocks, int ok)
3394 {
3395         /* another "blocks" (512byte) blocks have been synced */
3396         atomic_sub(blocks, &mddev->recovery_active);
3397         wake_up(&mddev->recovery_wait);
3398         if (!ok) {
3399                 set_bit(MD_RECOVERY_ERR, &mddev->recovery);
3400                 md_wakeup_thread(mddev->thread);
3401                 // stop recovery, signal do_sync ....
3402         }
3403 }
3404
3405
3406 /* md_write_start(mddev, bi)
3407  * If we need to update some array metadata (e.g. 'active' flag
3408  * in superblock) before writing, schedule a superblock update
3409  * and wait for it to complete.
3410  */
3411 void md_write_start(mddev_t *mddev, struct bio *bi)
3412 {
3413         DEFINE_WAIT(w);
3414         if (bio_data_dir(bi) != WRITE)
3415                 return;
3416
3417         atomic_inc(&mddev->writes_pending);
3418         if (mddev->in_sync) {
3419                 spin_lock(&mddev->write_lock);
3420                 if (mddev->in_sync) {
3421                         mddev->in_sync = 0;
3422                         mddev->sb_dirty = 1;
3423                         md_wakeup_thread(mddev->thread);
3424                 }
3425                 spin_unlock(&mddev->write_lock);
3426         }
3427         wait_event(mddev->sb_wait, mddev->sb_dirty==0);
3428 }
3429
3430 void md_write_end(mddev_t *mddev)
3431 {
3432         if (atomic_dec_and_test(&mddev->writes_pending)) {
3433                 if (mddev->safemode == 2)
3434                         md_wakeup_thread(mddev->thread);
3435                 else
3436                         mod_timer(&mddev->safemode_timer, jiffies + mddev->safemode_delay);
3437         }
3438 }
3439
3440 static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
3441
3442 #define SYNC_MARKS      10
3443 #define SYNC_MARK_STEP  (3*HZ)
3444 static void md_do_sync(mddev_t *mddev)
3445 {
3446         mddev_t *mddev2;
3447         unsigned int currspeed = 0,
3448                  window;
3449         sector_t max_sectors,j, io_sectors;
3450         unsigned long mark[SYNC_MARKS];
3451         sector_t mark_cnt[SYNC_MARKS];
3452         int last_mark,m;
3453         struct list_head *tmp;
3454         sector_t last_check;
3455         int skipped = 0;
3456
3457         /* just incase thread restarts... */
3458         if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
3459                 return;
3460
3461         /* we overload curr_resync somewhat here.
3462          * 0 == not engaged in resync at all
3463          * 2 == checking that there is no conflict with another sync
3464          * 1 == like 2, but have yielded to allow conflicting resync to
3465          *              commense
3466          * other == active in resync - this many blocks
3467          *
3468          * Before starting a resync we must have set curr_resync to
3469          * 2, and then checked that every "conflicting" array has curr_resync
3470          * less than ours.  When we find one that is the same or higher
3471          * we wait on resync_wait.  To avoid deadlock, we reduce curr_resync
3472          * to 1 if we choose to yield (based arbitrarily on address of mddev structure).
3473          * This will mean we have to start checking from the beginning again.
3474          *
3475          */
3476
3477         do {
3478                 mddev->curr_resync = 2;
3479
3480         try_again:
3481                 if (signal_pending(current)) {
3482                         flush_signals(current);
3483                         goto skip;
3484                 }
3485                 ITERATE_MDDEV(mddev2,tmp) {
3486                         printk(".");
3487                         if (mddev2 == mddev)
3488                                 continue;
3489                         if (mddev2->curr_resync &&
3490                             match_mddev_units(mddev,mddev2)) {
3491                                 DEFINE_WAIT(wq);
3492                                 if (mddev < mddev2 && mddev->curr_resync == 2) {
3493                                         /* arbitrarily yield */
3494                                         mddev->curr_resync = 1;
3495                                         wake_up(&resync_wait);
3496                                 }
3497                                 if (mddev > mddev2 && mddev->curr_resync == 1)
3498                                         /* no need to wait here, we can wait the next
3499                                          * time 'round when curr_resync == 2
3500                                          */
3501                                         continue;
3502                                 prepare_to_wait(&resync_wait, &wq, TASK_INTERRUPTIBLE);
3503                                 if (!signal_pending(current)
3504                                     && mddev2->curr_resync >= mddev->curr_resync) {
3505                                         printk(KERN_INFO "md: delaying resync of %s"
3506                                                " until %s has finished resync (they"
3507                                                " share one or more physical units)\n",
3508                                                mdname(mddev), mdname(mddev2));
3509                                         mddev_put(mddev2);
3510                                         schedule();
3511                                         finish_wait(&resync_wait, &wq);
3512                                         goto try_again;
3513                                 }
3514                                 finish_wait(&resync_wait, &wq);
3515                         }
3516                 }
3517         } while (mddev->curr_resync < 2);
3518
3519         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
3520                 /* resync follows the size requested by the personality,
3521                  * which defaults to physical size, but can be virtual size
3522                  */
3523                 max_sectors = mddev->resync_max_sectors;
3524         else
3525                 /* recovery follows the physical size of devices */
3526                 max_sectors = mddev->size << 1;
3527
3528         printk(KERN_INFO "md: syncing RAID array %s\n", mdname(mddev));
3529         printk(KERN_INFO "md: minimum _guaranteed_ reconstruction speed:"
3530                 " %d KB/sec/disc.\n", sysctl_speed_limit_min);
3531         printk(KERN_INFO "md: using maximum available idle IO bandwith "
3532                "(but not more than %d KB/sec) for reconstruction.\n",
3533                sysctl_speed_limit_max);
3534
3535         is_mddev_idle(mddev); /* this also initializes IO event counters */
3536         /* we don't use the checkpoint if there's a bitmap */
3537         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && !mddev->bitmap)
3538                 j = mddev->recovery_cp;
3539         else
3540                 j = 0;
3541         io_sectors = 0;
3542         for (m = 0; m < SYNC_MARKS; m++) {
3543                 mark[m] = jiffies;
3544                 mark_cnt[m] = io_sectors;
3545         }
3546         last_mark = 0;
3547         mddev->resync_mark = mark[last_mark];
3548         mddev->resync_mark_cnt = mark_cnt[last_mark];
3549
3550         /*
3551          * Tune reconstruction:
3552          */
3553         window = 32*(PAGE_SIZE/512);
3554         printk(KERN_INFO "md: using %dk window, over a total of %llu blocks.\n",
3555                 window/2,(unsigned long long) max_sectors/2);
3556
3557         atomic_set(&mddev->recovery_active, 0);
3558         init_waitqueue_head(&mddev->recovery_wait);
3559         last_check = 0;
3560
3561         if (j>2) {
3562                 printk(KERN_INFO
3563                         "md: resuming recovery of %s from checkpoint.\n",
3564                         mdname(mddev));
3565                 mddev->curr_resync = j;
3566         }
3567
3568         while (j < max_sectors) {
3569                 sector_t sectors;
3570
3571                 skipped = 0;
3572                 sectors = mddev->pers->sync_request(mddev, j, &skipped,
3573                                             currspeed < sysctl_speed_limit_min);
3574                 if (sectors == 0) {
3575                         set_bit(MD_RECOVERY_ERR, &mddev->recovery);
3576                         goto out;
3577                 }
3578
3579                 if (!skipped) { /* actual IO requested */
3580                         io_sectors += sectors;
3581                         atomic_add(sectors, &mddev->recovery_active);
3582                 }
3583
3584                 j += sectors;
3585                 if (j>1) mddev->curr_resync = j;
3586
3587
3588                 if (last_check + window > io_sectors || j == max_sectors)
3589                         continue;
3590
3591                 last_check = io_sectors;
3592
3593                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery) ||
3594                     test_bit(MD_RECOVERY_ERR, &mddev->recovery))
3595                         break;
3596
3597         repeat:
3598                 if (time_after_eq(jiffies, mark[last_mark] + SYNC_MARK_STEP )) {
3599                         /* step marks */
3600                         int next = (last_mark+1) % SYNC_MARKS;
3601
3602                         mddev->resync_mark = mark[next];
3603                         mddev->resync_mark_cnt = mark_cnt[next];
3604                         mark[next] = jiffies;
3605                         mark_cnt[next] = io_sectors - atomic_read(&mddev->recovery_active);
3606                         last_mark = next;
3607                 }
3608
3609
3610                 if (signal_pending(current)) {
3611                         /*
3612                          * got a signal, exit.
3613                          */
3614                         printk(KERN_INFO
3615                                 "md: md_do_sync() got signal ... exiting\n");
3616                         flush_signals(current);
3617                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3618                         goto out;
3619                 }
3620
3621                 /*
3622                  * this loop exits only if either when we are slower than
3623                  * the 'hard' speed limit, or the system was IO-idle for
3624                  * a jiffy.
3625                  * the system might be non-idle CPU-wise, but we only care
3626                  * about not overloading the IO subsystem. (things like an
3627                  * e2fsck being done on the RAID array should execute fast)
3628                  */
3629                 mddev->queue->unplug_fn(mddev->queue);
3630                 cond_resched();
3631
3632                 currspeed = ((unsigned long)(io_sectors-mddev->resync_mark_cnt))/2
3633                         /((jiffies-mddev->resync_mark)/HZ +1) +1;
3634
3635                 if (currspeed > sysctl_speed_limit_min) {
3636                         if ((currspeed > sysctl_speed_limit_max) ||
3637                                         !is_mddev_idle(mddev)) {
3638                                 msleep_interruptible(250);
3639                                 goto repeat;
3640                         }
3641                 }
3642         }
3643         printk(KERN_INFO "md: %s: sync done.\n",mdname(mddev));
3644         /*
3645          * this also signals 'finished resyncing' to md_stop
3646          */
3647  out:
3648         mddev->queue->unplug_fn(mddev->queue);
3649
3650         wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
3651
3652         /* tell personality that we are finished */
3653         mddev->pers->sync_request(mddev, max_sectors, &skipped, 1);
3654
3655         if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
3656             mddev->curr_resync > 2 &&
3657             mddev->curr_resync >= mddev->recovery_cp) {
3658                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
3659                         printk(KERN_INFO
3660                                 "md: checkpointing recovery of %s.\n",
3661                                 mdname(mddev));
3662                         mddev->recovery_cp = mddev->curr_resync;
3663                 } else
3664                         mddev->recovery_cp = MaxSector;
3665         }
3666
3667  skip:
3668         mddev->curr_resync = 0;
3669         wake_up(&resync_wait);
3670         set_bit(MD_RECOVERY_DONE, &mddev->recovery);
3671         md_wakeup_thread(mddev->thread);
3672 }
3673
3674
3675 /*
3676  * This routine is regularly called by all per-raid-array threads to
3677  * deal with generic issues like resync and super-block update.
3678  * Raid personalities that don't have a thread (linear/raid0) do not
3679  * need this as they never do any recovery or update the superblock.
3680  *
3681  * It does not do any resync itself, but rather "forks" off other threads
3682  * to do that as needed.
3683  * When it is determined that resync is needed, we set MD_RECOVERY_RUNNING in
3684  * "->recovery" and create a thread at ->sync_thread.
3685  * When the thread finishes it sets MD_RECOVERY_DONE (and might set MD_RECOVERY_ERR)
3686  * and wakeups up this thread which will reap the thread and finish up.
3687  * This thread also removes any faulty devices (with nr_pending == 0).
3688  *
3689  * The overall approach is:
3690  *  1/ if the superblock needs updating, update it.
3691  *  2/ If a recovery thread is running, don't do anything else.
3692  *  3/ If recovery has finished, clean up, possibly marking spares active.
3693  *  4/ If there are any faulty devices, remove them.
3694  *  5/ If array is degraded, try to add spares devices
3695  *  6/ If array has spares or is not in-sync, start a resync thread.
3696  */
3697 void md_check_recovery(mddev_t *mddev)
3698 {
3699         mdk_rdev_t *rdev;
3700         struct list_head *rtmp;
3701
3702
3703         if (mddev->bitmap)
3704                 bitmap_daemon_work(mddev->bitmap);
3705
3706         if (mddev->ro)
3707                 return;
3708
3709         if (signal_pending(current)) {
3710                 if (mddev->pers->sync_request) {
3711                         printk(KERN_INFO "md: %s in immediate safe mode\n",
3712                                mdname(mddev));
3713                         mddev->safemode = 2;
3714                 }
3715                 flush_signals(current);
3716         }
3717
3718         if ( ! (
3719                 mddev->sb_dirty ||
3720                 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
3721                 test_bit(MD_RECOVERY_DONE, &mddev->recovery) ||
3722                 (mddev->safemode == 1) ||
3723                 (mddev->safemode == 2 && ! atomic_read(&mddev->writes_pending)
3724                  && !mddev->in_sync && mddev->recovery_cp == MaxSector)
3725                 ))
3726                 return;
3727
3728         if (mddev_trylock(mddev)==0) {
3729                 int spares =0;
3730
3731                 spin_lock(&mddev->write_lock);
3732                 if (mddev->safemode && !atomic_read(&mddev->writes_pending) &&
3733                     !mddev->in_sync && mddev->recovery_cp == MaxSector) {
3734                         mddev->in_sync = 1;
3735                         mddev->sb_dirty = 1;
3736                 }
3737                 if (mddev->safemode == 1)
3738                         mddev->safemode = 0;
3739                 spin_unlock(&mddev->write_lock);
3740
3741                 if (mddev->sb_dirty)
3742                         md_update_sb(mddev);
3743
3744
3745                 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
3746                     !test_bit(MD_RECOVERY_DONE, &mddev->recovery)) {
3747                         /* resync/recovery still happening */
3748                         clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3749                         goto unlock;
3750                 }
3751                 if (mddev->sync_thread) {
3752                         /* resync has finished, collect result */
3753                         md_unregister_thread(mddev->sync_thread);
3754                         mddev->sync_thread = NULL;
3755                         if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
3756                             !test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
3757                                 /* success...*/
3758                                 /* activate any spares */
3759                                 mddev->pers->spare_active(mddev);
3760                         }
3761                         md_update_sb(mddev);
3762
3763                         /* if array is no-longer degraded, then any saved_raid_disk
3764                          * information must be scrapped
3765                          */
3766                         if (!mddev->degraded)
3767                                 ITERATE_RDEV(mddev,rdev,rtmp)
3768                                         rdev->saved_raid_disk = -1;
3769
3770                         mddev->recovery = 0;
3771                         /* flag recovery needed just to double check */
3772                         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3773                         goto unlock;
3774                 }
3775                 if (mddev->recovery)
3776                         /* probably just the RECOVERY_NEEDED flag */
3777                         mddev->recovery = 0;
3778
3779                 /* no recovery is running.
3780                  * remove any failed drives, then
3781                  * add spares if possible.
3782                  * Spare are also removed and re-added, to allow
3783                  * the personality to fail the re-add.
3784                  */
3785                 ITERATE_RDEV(mddev,rdev,rtmp)
3786                         if (rdev->raid_disk >= 0 &&
3787                             (rdev->faulty || ! rdev->in_sync) &&
3788                             atomic_read(&rdev->nr_pending)==0) {
3789                                 if (mddev->pers->hot_remove_disk(mddev, rdev->raid_disk)==0)
3790                                         rdev->raid_disk = -1;
3791                         }
3792
3793                 if (mddev->degraded) {
3794                         ITERATE_RDEV(mddev,rdev,rtmp)
3795                                 if (rdev->raid_disk < 0
3796                                     && !rdev->faulty) {
3797                                         if (mddev->pers->hot_add_disk(mddev,rdev))
3798                                                 spares++;
3799                                         else
3800                                                 break;
3801                                 }
3802                 }
3803
3804                 if (!spares && (mddev->recovery_cp == MaxSector )) {
3805                         /* nothing we can do ... */
3806                         goto unlock;
3807                 }
3808                 if (mddev->pers->sync_request) {
3809                         set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
3810                         if (!spares)
3811                                 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3812                         if (spares && mddev->bitmap && ! mddev->bitmap->file) {
3813                                 /* We are adding a device or devices to an array
3814                                  * which has the bitmap stored on all devices.
3815                                  * So make sure all bitmap pages get written
3816                                  */
3817                                 bitmap_write_all(mddev->bitmap);
3818                         }
3819                         mddev->sync_thread = md_register_thread(md_do_sync,
3820                                                                 mddev,
3821                                                                 "%s_resync");
3822                         if (!mddev->sync_thread) {
3823                                 printk(KERN_ERR "%s: could not start resync"
3824                                         " thread...\n",
3825                                         mdname(mddev));
3826                                 /* leave the spares where they are, it shouldn't hurt */
3827                                 mddev->recovery = 0;
3828                         } else {
3829                                 md_wakeup_thread(mddev->sync_thread);
3830                         }
3831                 }
3832         unlock:
3833                 mddev_unlock(mddev);
3834         }
3835 }
3836
3837 static int md_notify_reboot(struct notifier_block *this,
3838                             unsigned long code, void *x)
3839 {
3840         struct list_head *tmp;
3841         mddev_t *mddev;
3842
3843         if ((code == SYS_DOWN) || (code == SYS_HALT) || (code == SYS_POWER_OFF)) {
3844
3845                 printk(KERN_INFO "md: stopping all md devices.\n");
3846
3847                 ITERATE_MDDEV(mddev,tmp)
3848                         if (mddev_trylock(mddev)==0)
3849                                 do_md_stop (mddev, 1);
3850                 /*
3851                  * certain more exotic SCSI devices are known to be
3852                  * volatile wrt too early system reboots. While the
3853                  * right place to handle this issue is the given
3854                  * driver, we do want to have a safe RAID driver ...
3855                  */
3856                 mdelay(1000*1);
3857         }
3858         return NOTIFY_DONE;
3859 }
3860
3861 static struct notifier_block md_notifier = {
3862         .notifier_call  = md_notify_reboot,
3863         .next           = NULL,
3864         .priority       = INT_MAX, /* before any real devices */
3865 };
3866
3867 static void md_geninit(void)
3868 {
3869         struct proc_dir_entry *p;
3870
3871         dprintk("md: sizeof(mdp_super_t) = %d\n", (int)sizeof(mdp_super_t));
3872
3873         p = create_proc_entry("mdstat", S_IRUGO, NULL);
3874         if (p)
3875                 p->proc_fops = &md_seq_fops;
3876 }
3877
3878 static int __init md_init(void)
3879 {
3880         int minor;
3881
3882         printk(KERN_INFO "md: md driver %d.%d.%d MAX_MD_DEVS=%d,"
3883                         " MD_SB_DISKS=%d\n",
3884                         MD_MAJOR_VERSION, MD_MINOR_VERSION,
3885                         MD_PATCHLEVEL_VERSION, MAX_MD_DEVS, MD_SB_DISKS);
3886         printk(KERN_INFO "md: bitmap version %d.%d\n", BITMAP_MAJOR,
3887                         BITMAP_MINOR);
3888
3889         if (register_blkdev(MAJOR_NR, "md"))
3890                 return -1;
3891         if ((mdp_major=register_blkdev(0, "mdp"))<=0) {
3892                 unregister_blkdev(MAJOR_NR, "md");
3893                 return -1;
3894         }
3895         devfs_mk_dir("md");
3896         blk_register_region(MKDEV(MAJOR_NR, 0), MAX_MD_DEVS, THIS_MODULE,
3897                                 md_probe, NULL, NULL);
3898         blk_register_region(MKDEV(mdp_major, 0), MAX_MD_DEVS<<MdpMinorShift, THIS_MODULE,
3899                             md_probe, NULL, NULL);
3900
3901         for (minor=0; minor < MAX_MD_DEVS; ++minor)
3902                 devfs_mk_bdev(MKDEV(MAJOR_NR, minor),
3903                                 S_IFBLK|S_IRUSR|S_IWUSR,
3904                                 "md/%d", minor);
3905
3906         for (minor=0; minor < MAX_MD_DEVS; ++minor)
3907                 devfs_mk_bdev(MKDEV(mdp_major, minor<<MdpMinorShift),
3908                               S_IFBLK|S_IRUSR|S_IWUSR,
3909                               "md/mdp%d", minor);
3910
3911
3912         register_reboot_notifier(&md_notifier);
3913         raid_table_header = register_sysctl_table(raid_root_table, 1);
3914
3915         md_geninit();
3916         return (0);
3917 }
3918
3919
3920 #ifndef MODULE
3921
3922 /*
3923  * Searches all registered partitions for autorun RAID arrays
3924  * at boot time.
3925  */
3926 static dev_t detected_devices[128];
3927 static int dev_cnt;
3928
3929 void md_autodetect_dev(dev_t dev)
3930 {
3931         if (dev_cnt >= 0 && dev_cnt < 127)
3932                 detected_devices[dev_cnt++] = dev;
3933 }
3934
3935
3936 static void autostart_arrays(int part)
3937 {
3938         mdk_rdev_t *rdev;
3939         int i;
3940
3941         printk(KERN_INFO "md: Autodetecting RAID arrays.\n");
3942
3943         for (i = 0; i < dev_cnt; i++) {
3944                 dev_t dev = detected_devices[i];
3945
3946                 rdev = md_import_device(dev,0, 0);
3947                 if (IS_ERR(rdev))
3948                         continue;
3949
3950                 if (rdev->faulty) {
3951                         MD_BUG();
3952                         continue;
3953                 }
3954                 list_add(&rdev->same_set, &pending_raid_disks);
3955         }
3956         dev_cnt = 0;
3957
3958         autorun_devices(part);
3959 }
3960
3961 #endif
3962
3963 static __exit void md_exit(void)
3964 {
3965         mddev_t *mddev;
3966         struct list_head *tmp;
3967         int i;
3968         blk_unregister_region(MKDEV(MAJOR_NR,0), MAX_MD_DEVS);
3969         blk_unregister_region(MKDEV(mdp_major,0), MAX_MD_DEVS << MdpMinorShift);
3970         for (i=0; i < MAX_MD_DEVS; i++)
3971                 devfs_remove("md/%d", i);
3972         for (i=0; i < MAX_MD_DEVS; i++)
3973                 devfs_remove("md/d%d", i);
3974
3975         devfs_remove("md");
3976
3977         unregister_blkdev(MAJOR_NR,"md");
3978         unregister_blkdev(mdp_major, "mdp");
3979         unregister_reboot_notifier(&md_notifier);
3980         unregister_sysctl_table(raid_table_header);
3981         remove_proc_entry("mdstat", NULL);
3982         ITERATE_MDDEV(mddev,tmp) {
3983                 struct gendisk *disk = mddev->gendisk;
3984                 if (!disk)
3985                         continue;
3986                 export_array(mddev);
3987                 del_gendisk(disk);
3988                 put_disk(disk);
3989                 mddev->gendisk = NULL;
3990                 mddev_put(mddev);
3991         }
3992 }
3993
3994 module_init(md_init)
3995 module_exit(md_exit)
3996
3997 EXPORT_SYMBOL(register_md_personality);
3998 EXPORT_SYMBOL(unregister_md_personality);
3999 EXPORT_SYMBOL(md_error);
4000 EXPORT_SYMBOL(md_done_sync);
4001 EXPORT_SYMBOL(md_write_start);
4002 EXPORT_SYMBOL(md_write_end);
4003 EXPORT_SYMBOL(md_register_thread);
4004 EXPORT_SYMBOL(md_unregister_thread);
4005 EXPORT_SYMBOL(md_wakeup_thread);
4006 EXPORT_SYMBOL(md_print_devices);
4007 EXPORT_SYMBOL(md_check_recovery);
4008 MODULE_LICENSE("GPL");