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         md_wakeup_thread(mddev->thread);
 260 }
 261
 262 mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr)
 263 {
 264         mdk_rdev_t * rdev;
 265         struct list_head *tmp;
 266
 267         ITERATE_RDEV(mddev,rdev,tmp) {
 268                 if (rdev->desc_nr == nr)
 269                         return rdev;
 270         }
 271         return NULL;
 272 }
 273
 274 static mdk_rdev_t * find_rdev(mddev_t * mddev, dev_t dev)
 275 {
 276         struct list_head *tmp;
 277         mdk_rdev_t *rdev;
 278
 279         ITERATE_RDEV(mddev,rdev,tmp) {
 280                 if (rdev->bdev->bd_dev == dev)
 281                         return rdev;
 282         }
 283         return NULL;
 284 }
 285
 286 static inline sector_t calc_dev_sboffset(struct block_device *bdev)
 287 {
 288         sector_t size = bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
 289         return MD_NEW_SIZE_BLOCKS(size);
 290 }
 291
 292 static sector_t calc_dev_size(mdk_rdev_t *rdev, unsigned chunk_size)
 293 {
 294         sector_t size;
 295
 296         size = rdev->sb_offset;
 297
 298         if (chunk_size)
 299                 size &= ~((sector_t)chunk_size/1024 - 1);
 300         return size;
 301 }
 302
 303 static int alloc_disk_sb(mdk_rdev_t * rdev)
 304 {
 305         if (rdev->sb_page)
 306                 MD_BUG();
 307
 308         rdev->sb_page = alloc_page(GFP_KERNEL);
 309         if (!rdev->sb_page) {
 310                 printk(KERN_ALERT "md: out of memory.\n");
 311                 return -EINVAL;
 312         }
 313
 314         return 0;
 315 }
 316
 317 static void free_disk_sb(mdk_rdev_t * rdev)
 318 {
 319         if (rdev->sb_page) {
 320                 page_cache_release(rdev->sb_page);
 321                 rdev->sb_loaded = 0;
 322                 rdev->sb_page = NULL;
 323                 rdev->sb_offset = 0;
 324                 rdev->size = 0;
 325         }
 326 }
 327
 328
 329 static int super_written(struct bio *bio, unsigned int bytes_done, int error)
 330 {
 331         mdk_rdev_t *rdev = bio->bi_private;
 332         if (bio->bi_size)
 333                 return 1;
 334
 335         if (error || !test_bit(BIO_UPTODATE, &bio->bi_flags))
 336                 md_error(rdev->mddev, rdev);
 337
 338         if (atomic_dec_and_test(&rdev->mddev->pending_writes))
 339                 wake_up(&rdev->mddev->sb_wait);
 340         bio_put(bio);
 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                 mddev->bitmap_offset = 0;
 626
 627                 if (sb->state & (1<<MD_SB_CLEAN))
 628                         mddev->recovery_cp = MaxSector;
 629                 else {
 630                         if (sb->events_hi == sb->cp_events_hi &&
 631                                 sb->events_lo == sb->cp_events_lo) {
 632                                 mddev->recovery_cp = sb->recovery_cp;
 633                         } else
 634                                 mddev->recovery_cp = 0;
 635                 }
 636
 637                 memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
 638                 memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
 639                 memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
 640                 memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
 641
 642                 mddev->max_disks = MD_SB_DISKS;
 643
 644                 if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
 645                     mddev->bitmap_file == NULL) {
 646                         if (mddev->level != 1) {
 647                                 /* FIXME use a better test */
 648                                 printk(KERN_WARNING "md: bitmaps only support for raid1\n");
 649                                 return -EINVAL;
 650                         }
 651                         mddev->bitmap_offset = (MD_SB_BYTES >> 9);
 652                 }
 653
 654         } else if (mddev->pers == NULL) {
 655                 /* Insist on good event counter while assembling */
 656                 __u64 ev1 = md_event(sb);
 657                 ++ev1;
 658                 if (ev1 < mddev->events)
 659                         return -EINVAL;
 660         } else if (mddev->bitmap) {
 661                 /* if adding to array with a bitmap, then we can accept an
 662                  * older device ... but not too old.
 663                  */
 664                 __u64 ev1 = md_event(sb);
 665                 if (ev1 < mddev->bitmap->events_cleared)
 666                         return 0;
 667         } else /* just a hot-add of a new device, leave raid_disk at -1 */
 668                 return 0;
 669
 670         if (mddev->level != LEVEL_MULTIPATH) {
 671                 rdev->faulty = 0;
 672                 desc = sb->disks + rdev->desc_nr;
 673
 674                 if (desc->state & (1<<MD_DISK_FAULTY))
 675                         rdev->faulty = 1;
 676                 else if (desc->state & (1<<MD_DISK_SYNC) &&
 677                          desc->raid_disk < mddev->raid_disks) {
 678                         rdev->in_sync = 1;
 679                         rdev->raid_disk = desc->raid_disk;
 680                 }
 681         } else /* MULTIPATH are always insync */
 682                 rdev->in_sync = 1;
 683         return 0;
 684 }
 685
 686 /*
 687  * sync_super for 0.90.0
 688  */
 689 static void super_90_sync(mddev_t *mddev, mdk_rdev_t *rdev)
 690 {
 691         mdp_super_t *sb;
 692         struct list_head *tmp;
 693         mdk_rdev_t *rdev2;
 694         int next_spare = mddev->raid_disks;
 695
 696         /* make rdev->sb match mddev data..
 697          *
 698          * 1/ zero out disks
 699          * 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
 700          * 3/ any empty disks < next_spare become removed
 701          *
 702          * disks[0] gets initialised to REMOVED because
 703          * we cannot be sure from other fields if it has
 704          * been initialised or not.
 705          */
 706         int i;
 707         int active=0, working=0,failed=0,spare=0,nr_disks=0;
 708
 709         sb = (mdp_super_t*)page_address(rdev->sb_page);
 710
 711         memset(sb, 0, sizeof(*sb));
 712
 713         sb->md_magic = MD_SB_MAGIC;
 714         sb->major_version = mddev->major_version;
 715         sb->minor_version = mddev->minor_version;
 716         sb->patch_version = mddev->patch_version;
 717         sb->gvalid_words  = 0; /* ignored */
 718         memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
 719         memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
 720         memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
 721         memcpy(&sb->set_uuid3, mddev->uuid+12,4);
 722
 723         sb->ctime = mddev->ctime;
 724         sb->level = mddev->level;
 725         sb->size  = mddev->size;
 726         sb->raid_disks = mddev->raid_disks;
 727         sb->md_minor = mddev->md_minor;
 728         sb->not_persistent = !mddev->persistent;
 729         sb->utime = mddev->utime;
 730         sb->state = 0;
 731         sb->events_hi = (mddev->events>>32);
 732         sb->events_lo = (u32)mddev->events;
 733
 734         if (mddev->in_sync)
 735         {
 736                 sb->recovery_cp = mddev->recovery_cp;
 737                 sb->cp_events_hi = (mddev->events>>32);
 738                 sb->cp_events_lo = (u32)mddev->events;
 739                 if (mddev->recovery_cp == MaxSector)
 740                         sb->state = (1<< MD_SB_CLEAN);
 741         } else
 742                 sb->recovery_cp = 0;
 743
 744         sb->layout = mddev->layout;
 745         sb->chunk_size = mddev->chunk_size;
 746
 747         if (mddev->bitmap && mddev->bitmap_file == NULL)
 748                 sb->state |= (1<<MD_SB_BITMAP_PRESENT);
 749
 750         sb->disks[0].state = (1<<MD_DISK_REMOVED);
 751         ITERATE_RDEV(mddev,rdev2,tmp) {
 752                 mdp_disk_t *d;
 753                 if (rdev2->raid_disk >= 0 && rdev2->in_sync && !rdev2->faulty)
 754                         rdev2->desc_nr = rdev2->raid_disk;
 755                 else
 756                         rdev2->desc_nr = next_spare++;
 757                 d = &sb->disks[rdev2->desc_nr];
 758                 nr_disks++;
 759                 d->number = rdev2->desc_nr;
 760                 d->major = MAJOR(rdev2->bdev->bd_dev);
 761                 d->minor = MINOR(rdev2->bdev->bd_dev);
 762                 if (rdev2->raid_disk >= 0 && rdev->in_sync && !rdev2->faulty)
 763                         d->raid_disk = rdev2->raid_disk;
 764                 else
 765                         d->raid_disk = rdev2->desc_nr; /* compatibility */
 766                 if (rdev2->faulty) {
 767                         d->state = (1<<MD_DISK_FAULTY);
 768                         failed++;
 769                 } else if (rdev2->in_sync) {
 770                         d->state = (1<<MD_DISK_ACTIVE);
 771                         d->state |= (1<<MD_DISK_SYNC);
 772                         active++;
 773                         working++;
 774                 } else {
 775                         d->state = 0;
 776                         spare++;
 777                         working++;
 778                 }
 779         }
 780
 781         /* now set the "removed" and "faulty" bits on any missing devices */
 782         for (i=0 ; i < mddev->raid_disks ; i++) {
 783                 mdp_disk_t *d = &sb->disks[i];
 784                 if (d->state == 0 && d->number == 0) {
 785                         d->number = i;
 786                         d->raid_disk = i;
 787                         d->state = (1<<MD_DISK_REMOVED);
 788                         d->state |= (1<<MD_DISK_FAULTY);
 789                         failed++;
 790                 }
 791         }
 792         sb->nr_disks = nr_disks;
 793         sb->active_disks = active;
 794         sb->working_disks = working;
 795         sb->failed_disks = failed;
 796         sb->spare_disks = spare;
 797
 798         sb->this_disk = sb->disks[rdev->desc_nr];
 799         sb->sb_csum = calc_sb_csum(sb);
 800 }
 801
 802 /*
 803  * version 1 superblock
 804  */
 805
 806 static unsigned int calc_sb_1_csum(struct mdp_superblock_1 * sb)
 807 {
 808         unsigned int disk_csum, csum;
 809         unsigned long long newcsum;
 810         int size = 256 + le32_to_cpu(sb->max_dev)*2;
 811         unsigned int *isuper = (unsigned int*)sb;
 812         int i;
 813
 814         disk_csum = sb->sb_csum;
 815         sb->sb_csum = 0;
 816         newcsum = 0;
 817         for (i=0; size>=4; size -= 4 )
 818                 newcsum += le32_to_cpu(*isuper++);
 819
 820         if (size == 2)
 821                 newcsum += le16_to_cpu(*(unsigned short*) isuper);
 822
 823         csum = (newcsum & 0xffffffff) + (newcsum >> 32);
 824         sb->sb_csum = disk_csum;
 825         return cpu_to_le32(csum);
 826 }
 827
 828 static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
 829 {
 830         struct mdp_superblock_1 *sb;
 831         int ret;
 832         sector_t sb_offset;
 833         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
 834
 835         /*
 836          * Calculate the position of the superblock.
 837          * It is always aligned to a 4K boundary and
 838          * depeding on minor_version, it can be:
 839          * 0: At least 8K, but less than 12K, from end of device
 840          * 1: At start of device
 841          * 2: 4K from start of device.
 842          */
 843         switch(minor_version) {
 844         case 0:
 845                 sb_offset = rdev->bdev->bd_inode->i_size >> 9;
 846                 sb_offset -= 8*2;
 847                 sb_offset &= ~(sector_t)(4*2-1);
 848                 /* convert from sectors to K */
 849                 sb_offset /= 2;
 850                 break;
 851         case 1:
 852                 sb_offset = 0;
 853                 break;
 854         case 2:
 855                 sb_offset = 4;
 856                 break;
 857         default:
 858                 return -EINVAL;
 859         }
 860         rdev->sb_offset = sb_offset;
 861
 862         ret = read_disk_sb(rdev);
 863         if (ret) return ret;
 864
 865
 866         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
 867
 868         if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
 869             sb->major_version != cpu_to_le32(1) ||
 870             le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
 871             le64_to_cpu(sb->super_offset) != (rdev->sb_offset<<1) ||
 872             sb->feature_map != 0)
 873                 return -EINVAL;
 874
 875         if (calc_sb_1_csum(sb) != sb->sb_csum) {
 876                 printk("md: invalid superblock checksum on %s\n",
 877                         bdevname(rdev->bdev,b));
 878                 return -EINVAL;
 879         }
 880         if (le64_to_cpu(sb->data_size) < 10) {
 881                 printk("md: data_size too small on %s\n",
 882                        bdevname(rdev->bdev,b));
 883                 return -EINVAL;
 884         }
 885         rdev->preferred_minor = 0xffff;
 886         rdev->data_offset = le64_to_cpu(sb->data_offset);
 887
 888         if (refdev == 0)
 889                 return 1;
 890         else {
 891                 __u64 ev1, ev2;
 892                 struct mdp_superblock_1 *refsb =
 893                         (struct mdp_superblock_1*)page_address(refdev->sb_page);
 894
 895                 if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
 896                     sb->level != refsb->level ||
 897                     sb->layout != refsb->layout ||
 898                     sb->chunksize != refsb->chunksize) {
 899                         printk(KERN_WARNING "md: %s has strangely different"
 900                                 " superblock to %s\n",
 901                                 bdevname(rdev->bdev,b),
 902                                 bdevname(refdev->bdev,b2));
 903                         return -EINVAL;
 904                 }
 905                 ev1 = le64_to_cpu(sb->events);
 906                 ev2 = le64_to_cpu(refsb->events);
 907
 908                 if (ev1 > ev2)
 909                         return 1;
 910         }
 911         if (minor_version)
 912                 rdev->size = ((rdev->bdev->bd_inode->i_size>>9) - le64_to_cpu(sb->data_offset)) / 2;
 913         else
 914                 rdev->size = rdev->sb_offset;
 915         if (rdev->size < le64_to_cpu(sb->data_size)/2)
 916                 return -EINVAL;
 917         rdev->size = le64_to_cpu(sb->data_size)/2;
 918         if (le32_to_cpu(sb->chunksize))
 919                 rdev->size &= ~((sector_t)le32_to_cpu(sb->chunksize)/2 - 1);
 920         return 0;
 921 }
 922
 923 static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
 924 {
 925         struct mdp_superblock_1 *sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
 926
 927         rdev->raid_disk = -1;
 928         rdev->in_sync = 0;
 929         if (mddev->raid_disks == 0) {
 930                 mddev->major_version = 1;
 931                 mddev->patch_version = 0;
 932                 mddev->persistent = 1;
 933                 mddev->chunk_size = le32_to_cpu(sb->chunksize) << 9;
 934                 mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);
 935                 mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);
 936                 mddev->level = le32_to_cpu(sb->level);
 937                 mddev->layout = le32_to_cpu(sb->layout);
 938                 mddev->raid_disks = le32_to_cpu(sb->raid_disks);
 939                 mddev->size = le64_to_cpu(sb->size)/2;
 940                 mddev->events = le64_to_cpu(sb->events);
 941                 mddev->bitmap_offset = 0;
 942
 943                 mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
 944                 memcpy(mddev->uuid, sb->set_uuid, 16);
 945
 946                 mddev->max_disks =  (4096-256)/2;
 947
 948                 if ((le32_to_cpu(sb->feature_map) & 1) &&
 949                     mddev->bitmap_file == NULL ) {
 950                         if (mddev->level != 1) {
 951                                 printk(KERN_WARNING "md: bitmaps only supported for raid1\n");
 952                                 return -EINVAL;
 953                         }
 954                         mddev->bitmap_offset = (__s32)le32_to_cpu(sb->bitmap_offset);
 955                 }
 956         } else if (mddev->pers == NULL) {
 957                 /* Insist of good event counter while assembling */
 958                 __u64 ev1 = le64_to_cpu(sb->events);
 959                 ++ev1;
 960                 if (ev1 < mddev->events)
 961                         return -EINVAL;
 962         } else if (mddev->bitmap) {
 963                 /* If adding to array with a bitmap, then we can accept an
 964                  * older device, but not too old.
 965                  */
 966                 __u64 ev1 = le64_to_cpu(sb->events);
 967                 if (ev1 < mddev->bitmap->events_cleared)
 968                         return 0;
 969         } else /* just a hot-add of a new device, leave raid_disk at -1 */
 970                 return 0;
 971
 972         if (mddev->level != LEVEL_MULTIPATH) {
 973                 int role;
 974                 rdev->desc_nr = le32_to_cpu(sb->dev_number);
 975                 role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
 976                 switch(role) {
 977                 case 0xffff: /* spare */
 978                         rdev->faulty = 0;
 979                         break;
 980                 case 0xfffe: /* faulty */
 981                         rdev->faulty = 1;
 982                         break;
 983                 default:
 984                         rdev->in_sync = 1;
 985                         rdev->faulty = 0;
 986                         rdev->raid_disk = role;
 987                         break;
 988                 }
 989         } else /* MULTIPATH are always insync */
 990                 rdev->in_sync = 1;
 991
 992         return 0;
 993 }
 994
 995 static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
 996 {
 997         struct mdp_superblock_1 *sb;
 998         struct list_head *tmp;
 999         mdk_rdev_t *rdev2;
1000         int max_dev, i;
1001         /* make rdev->sb match mddev and rdev data. */
1002
1003         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1004
1005         sb->feature_map = 0;
1006         sb->pad0 = 0;
1007         memset(sb->pad1, 0, sizeof(sb->pad1));
1008         memset(sb->pad2, 0, sizeof(sb->pad2));
1009         memset(sb->pad3, 0, sizeof(sb->pad3));
1010
1011         sb->utime = cpu_to_le64((__u64)mddev->utime);
1012         sb->events = cpu_to_le64(mddev->events);
1013         if (mddev->in_sync)
1014                 sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
1015         else
1016                 sb->resync_offset = cpu_to_le64(0);
1017
1018         if (mddev->bitmap && mddev->bitmap_file == NULL) {
1019                 sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_offset);
1020                 sb->feature_map = cpu_to_le32(1);
1021         }
1022
1023         max_dev = 0;
1024         ITERATE_RDEV(mddev,rdev2,tmp)
1025                 if (rdev2->desc_nr+1 > max_dev)
1026                         max_dev = rdev2->desc_nr+1;
1027
1028         sb->max_dev = cpu_to_le32(max_dev);
1029         for (i=0; i<max_dev;i++)
1030                 sb->dev_roles[i] = cpu_to_le16(0xfffe);
1031
1032         ITERATE_RDEV(mddev,rdev2,tmp) {
1033                 i = rdev2->desc_nr;
1034                 if (rdev2->faulty)
1035                         sb->dev_roles[i] = cpu_to_le16(0xfffe);
1036                 else if (rdev2->in_sync)
1037                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1038                 else
1039                         sb->dev_roles[i] = cpu_to_le16(0xffff);
1040         }
1041
1042         sb->recovery_offset = cpu_to_le64(0); /* not supported yet */
1043         sb->sb_csum = calc_sb_1_csum(sb);
1044 }
1045
1046
1047 static struct super_type super_types[] = {
1048         [0] = {
1049                 .name   = "0.90.0",
1050                 .owner  = THIS_MODULE,
1051                 .load_super     = super_90_load,
1052                 .validate_super = super_90_validate,
1053                 .sync_super     = super_90_sync,
1054         },
1055         [1] = {
1056                 .name   = "md-1",
1057                 .owner  = THIS_MODULE,
1058                 .load_super     = super_1_load,
1059                 .validate_super = super_1_validate,
1060                 .sync_super     = super_1_sync,
1061         },
1062 };
1063
1064 static mdk_rdev_t * match_dev_unit(mddev_t *mddev, mdk_rdev_t *dev)
1065 {
1066         struct list_head *tmp;
1067         mdk_rdev_t *rdev;
1068
1069         ITERATE_RDEV(mddev,rdev,tmp)
1070                 if (rdev->bdev->bd_contains == dev->bdev->bd_contains)
1071                         return rdev;
1072
1073         return NULL;
1074 }
1075
1076 static int match_mddev_units(mddev_t *mddev1, mddev_t *mddev2)
1077 {
1078         struct list_head *tmp;
1079         mdk_rdev_t *rdev;
1080
1081         ITERATE_RDEV(mddev1,rdev,tmp)
1082                 if (match_dev_unit(mddev2, rdev))
1083                         return 1;
1084
1085         return 0;
1086 }
1087
1088 static LIST_HEAD(pending_raid_disks);
1089
1090 static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
1091 {
1092         mdk_rdev_t *same_pdev;
1093         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1094
1095         if (rdev->mddev) {
1096                 MD_BUG();
1097                 return -EINVAL;
1098         }
1099         same_pdev = match_dev_unit(mddev, rdev);
1100         if (same_pdev)
1101                 printk(KERN_WARNING
1102                         "%s: WARNING: %s appears to be on the same physical"
1103                         " disk as %s. True\n     protection against single-disk"
1104                         " failure might be compromised.\n",
1105                         mdname(mddev), bdevname(rdev->bdev,b),
1106                         bdevname(same_pdev->bdev,b2));
1107
1108         /* Verify rdev->desc_nr is unique.
1109          * If it is -1, assign a free number, else
1110          * check number is not in use
1111          */
1112         if (rdev->desc_nr < 0) {
1113                 int choice = 0;
1114                 if (mddev->pers) choice = mddev->raid_disks;
1115                 while (find_rdev_nr(mddev, choice))
1116                         choice++;
1117                 rdev->desc_nr = choice;
1118         } else {
1119                 if (find_rdev_nr(mddev, rdev->desc_nr))
1120                         return -EBUSY;
1121         }
1122
1123         list_add(&rdev->same_set, &mddev->disks);
1124         rdev->mddev = mddev;
1125         printk(KERN_INFO "md: bind<%s>\n", bdevname(rdev->bdev,b));
1126         return 0;
1127 }
1128
1129 static void unbind_rdev_from_array(mdk_rdev_t * rdev)
1130 {
1131         char b[BDEVNAME_SIZE];
1132         if (!rdev->mddev) {
1133                 MD_BUG();
1134                 return;
1135         }
1136         list_del_init(&rdev->same_set);
1137         printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
1138         rdev->mddev = NULL;
1139 }
1140
1141 /*
1142  * prevent the device from being mounted, repartitioned or
1143  * otherwise reused by a RAID array (or any other kernel
1144  * subsystem), by bd_claiming the device.
1145  */
1146 static int lock_rdev(mdk_rdev_t *rdev, dev_t dev)
1147 {
1148         int err = 0;
1149         struct block_device *bdev;
1150         char b[BDEVNAME_SIZE];
1151
1152         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
1153         if (IS_ERR(bdev)) {
1154                 printk(KERN_ERR "md: could not open %s.\n",
1155                         __bdevname(dev, b));
1156                 return PTR_ERR(bdev);
1157         }
1158         err = bd_claim(bdev, rdev);
1159         if (err) {
1160                 printk(KERN_ERR "md: could not bd_claim %s.\n",
1161                         bdevname(bdev, b));
1162                 blkdev_put(bdev);
1163                 return err;
1164         }
1165         rdev->bdev = bdev;
1166         return err;
1167 }
1168
1169 static void unlock_rdev(mdk_rdev_t *rdev)
1170 {
1171         struct block_device *bdev = rdev->bdev;
1172         rdev->bdev = NULL;
1173         if (!bdev)
1174                 MD_BUG();
1175         bd_release(bdev);
1176         blkdev_put(bdev);
1177 }
1178
1179 void md_autodetect_dev(dev_t dev);
1180
1181 static void export_rdev(mdk_rdev_t * rdev)
1182 {
1183         char b[BDEVNAME_SIZE];
1184         printk(KERN_INFO "md: export_rdev(%s)\n",
1185                 bdevname(rdev->bdev,b));
1186         if (rdev->mddev)
1187                 MD_BUG();
1188         free_disk_sb(rdev);
1189         list_del_init(&rdev->same_set);
1190 #ifndef MODULE
1191         md_autodetect_dev(rdev->bdev->bd_dev);
1192 #endif
1193         unlock_rdev(rdev);
1194         kfree(rdev);
1195 }
1196
1197 static void kick_rdev_from_array(mdk_rdev_t * rdev)
1198 {
1199         unbind_rdev_from_array(rdev);
1200         export_rdev(rdev);
1201 }
1202
1203 static void export_array(mddev_t *mddev)
1204 {
1205         struct list_head *tmp;
1206         mdk_rdev_t *rdev;
1207
1208         ITERATE_RDEV(mddev,rdev,tmp) {
1209                 if (!rdev->mddev) {
1210                         MD_BUG();
1211                         continue;
1212                 }
1213                 kick_rdev_from_array(rdev);
1214         }
1215         if (!list_empty(&mddev->disks))
1216                 MD_BUG();
1217         mddev->raid_disks = 0;
1218         mddev->major_version = 0;
1219 }
1220
1221 static void print_desc(mdp_disk_t *desc)
1222 {
1223         printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
1224                 desc->major,desc->minor,desc->raid_disk,desc->state);
1225 }
1226
1227 static void print_sb(mdp_super_t *sb)
1228 {
1229         int i;
1230
1231         printk(KERN_INFO
1232                 "md:  SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
1233                 sb->major_version, sb->minor_version, sb->patch_version,
1234                 sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
1235                 sb->ctime);
1236         printk(KERN_INFO "md:     L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
1237                 sb->level, sb->size, sb->nr_disks, sb->raid_disks,
1238                 sb->md_minor, sb->layout, sb->chunk_size);
1239         printk(KERN_INFO "md:     UT:%08x ST:%d AD:%d WD:%d"
1240                 " FD:%d SD:%d CSUM:%08x E:%08lx\n",
1241                 sb->utime, sb->state, sb->active_disks, sb->working_disks,
1242                 sb->failed_disks, sb->spare_disks,
1243                 sb->sb_csum, (unsigned long)sb->events_lo);
1244
1245         printk(KERN_INFO);
1246         for (i = 0; i < MD_SB_DISKS; i++) {
1247                 mdp_disk_t *desc;
1248
1249                 desc = sb->disks + i;
1250                 if (desc->number || desc->major || desc->minor ||
1251                     desc->raid_disk || (desc->state && (desc->state != 4))) {
1252                         printk("     D %2d: ", i);
1253                         print_desc(desc);
1254                 }
1255         }
1256         printk(KERN_INFO "md:     THIS: ");
1257         print_desc(&sb->this_disk);
1258
1259 }
1260
1261 static void print_rdev(mdk_rdev_t *rdev)
1262 {
1263         char b[BDEVNAME_SIZE];
1264         printk(KERN_INFO "md: rdev %s, SZ:%08llu F:%d S:%d DN:%u\n",
1265                 bdevname(rdev->bdev,b), (unsigned long long)rdev->size,
1266                 rdev->faulty, rdev->in_sync, rdev->desc_nr);
1267         if (rdev->sb_loaded) {
1268                 printk(KERN_INFO "md: rdev superblock:\n");
1269                 print_sb((mdp_super_t*)page_address(rdev->sb_page));
1270         } else
1271                 printk(KERN_INFO "md: no rdev superblock!\n");
1272 }
1273
1274 void md_print_devices(void)
1275 {
1276         struct list_head *tmp, *tmp2;
1277         mdk_rdev_t *rdev;
1278         mddev_t *mddev;
1279         char b[BDEVNAME_SIZE];
1280
1281         printk("\n");
1282         printk("md:     **********************************\n");
1283         printk("md:     * <COMPLETE RAID STATE PRINTOUT> *\n");
1284         printk("md:     **********************************\n");
1285         ITERATE_MDDEV(mddev,tmp) {
1286
1287                 if (mddev->bitmap)
1288                         bitmap_print_sb(mddev->bitmap);
1289                 else
1290                         printk("%s: ", mdname(mddev));
1291                 ITERATE_RDEV(mddev,rdev,tmp2)
1292                         printk("<%s>", bdevname(rdev->bdev,b));
1293                 printk("\n");
1294
1295                 ITERATE_RDEV(mddev,rdev,tmp2)
1296                         print_rdev(rdev);
1297         }
1298         printk("md:     **********************************\n");
1299         printk("\n");
1300 }
1301
1302
1303 static void sync_sbs(mddev_t * mddev)
1304 {
1305         mdk_rdev_t *rdev;
1306         struct list_head *tmp;
1307
1308         ITERATE_RDEV(mddev,rdev,tmp) {
1309                 super_types[mddev->major_version].
1310                         sync_super(mddev, rdev);
1311                 rdev->sb_loaded = 1;
1312         }
1313 }
1314
1315 static void md_update_sb(mddev_t * mddev)
1316 {
1317         int err;
1318         struct list_head *tmp;
1319         mdk_rdev_t *rdev;
1320         int sync_req;
1321
1322 repeat:
1323         spin_lock(&mddev->write_lock);
1324         sync_req = mddev->in_sync;
1325         mddev->utime = get_seconds();
1326         mddev->events ++;
1327
1328         if (!mddev->events) {
1329                 /*
1330                  * oops, this 64-bit counter should never wrap.
1331                  * Either we are in around ~1 trillion A.C., assuming
1332                  * 1 reboot per second, or we have a bug:
1333                  */
1334                 MD_BUG();
1335                 mddev->events --;
1336         }
1337         mddev->sb_dirty = 2;
1338         sync_sbs(mddev);
1339
1340         /*
1341          * do not write anything to disk if using
1342          * nonpersistent superblocks
1343          */
1344         if (!mddev->persistent) {
1345                 mddev->sb_dirty = 0;
1346                 spin_unlock(&mddev->write_lock);
1347                 wake_up(&mddev->sb_wait);
1348                 return;
1349         }
1350         spin_unlock(&mddev->write_lock);
1351
1352         dprintk(KERN_INFO
1353                 "md: updating %s RAID superblock on device (in sync %d)\n",
1354                 mdname(mddev),mddev->in_sync);
1355
1356         err = bitmap_update_sb(mddev->bitmap);
1357         ITERATE_RDEV(mddev,rdev,tmp) {
1358                 char b[BDEVNAME_SIZE];
1359                 dprintk(KERN_INFO "md: ");
1360                 if (rdev->faulty)
1361                         dprintk("(skipping faulty ");
1362
1363                 dprintk("%s ", bdevname(rdev->bdev,b));
1364                 if (!rdev->faulty) {
1365                         md_super_write(mddev,rdev,
1366                                        rdev->sb_offset<<1, MD_SB_BYTES,
1367                                        rdev->sb_page);
1368                         dprintk(KERN_INFO "(write) %s's sb offset: %llu\n",
1369                                 bdevname(rdev->bdev,b),
1370                                 (unsigned long long)rdev->sb_offset);
1371
1372                 } else
1373                         dprintk(")\n");
1374                 if (mddev->level == LEVEL_MULTIPATH)
1375                         /* only need to write one superblock... */
1376                         break;
1377         }
1378         wait_event(mddev->sb_wait, atomic_read(&mddev->pending_writes)==0);
1379         /* if there was a failure, sb_dirty was set to 1, and we re-write super */
1380
1381         spin_lock(&mddev->write_lock);
1382         if (mddev->in_sync != sync_req|| mddev->sb_dirty == 1) {
1383                 /* have to write it out again */
1384                 spin_unlock(&mddev->write_lock);
1385                 goto repeat;
1386         }
1387         mddev->sb_dirty = 0;
1388         spin_unlock(&mddev->write_lock);
1389         wake_up(&mddev->sb_wait);
1390
1391 }
1392
1393 /*
1394  * Import a device. If 'super_format' >= 0, then sanity check the superblock
1395  *
1396  * mark the device faulty if:
1397  *
1398  *   - the device is nonexistent (zero size)
1399  *   - the device has no valid superblock
1400  *
1401  * a faulty rdev _never_ has rdev->sb set.
1402  */
1403 static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_minor)
1404 {
1405         char b[BDEVNAME_SIZE];
1406         int err;
1407         mdk_rdev_t *rdev;
1408         sector_t size;
1409
1410         rdev = (mdk_rdev_t *) kmalloc(sizeof(*rdev), GFP_KERNEL);
1411         if (!rdev) {
1412                 printk(KERN_ERR "md: could not alloc mem for new device!\n");
1413                 return ERR_PTR(-ENOMEM);
1414         }
1415         memset(rdev, 0, sizeof(*rdev));
1416
1417         if ((err = alloc_disk_sb(rdev)))
1418                 goto abort_free;
1419
1420         err = lock_rdev(rdev, newdev);
1421         if (err)
1422                 goto abort_free;
1423
1424         rdev->desc_nr = -1;
1425         rdev->faulty = 0;
1426         rdev->in_sync = 0;
1427         rdev->data_offset = 0;
1428         atomic_set(&rdev->nr_pending, 0);
1429
1430         size = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
1431         if (!size) {
1432                 printk(KERN_WARNING
1433                         "md: %s has zero or unknown size, marking faulty!\n",
1434                         bdevname(rdev->bdev,b));
1435                 err = -EINVAL;
1436                 goto abort_free;
1437         }
1438
1439         if (super_format >= 0) {
1440                 err = super_types[super_format].
1441                         load_super(rdev, NULL, super_minor);
1442                 if (err == -EINVAL) {
1443                         printk(KERN_WARNING
1444                                 "md: %s has invalid sb, not importing!\n",
1445                                 bdevname(rdev->bdev,b));
1446                         goto abort_free;
1447                 }
1448                 if (err < 0) {
1449                         printk(KERN_WARNING
1450                                 "md: could not read %s's sb, not importing!\n",
1451                                 bdevname(rdev->bdev,b));
1452                         goto abort_free;
1453                 }
1454         }
1455         INIT_LIST_HEAD(&rdev->same_set);
1456
1457         return rdev;
1458
1459 abort_free:
1460         if (rdev->sb_page) {
1461                 if (rdev->bdev)
1462                         unlock_rdev(rdev);
1463                 free_disk_sb(rdev);
1464         }
1465         kfree(rdev);
1466         return ERR_PTR(err);
1467 }
1468
1469 /*
1470  * Check a full RAID array for plausibility
1471  */
1472
1473
1474 static void analyze_sbs(mddev_t * mddev)
1475 {
1476         int i;
1477         struct list_head *tmp;
1478         mdk_rdev_t *rdev, *freshest;
1479         char b[BDEVNAME_SIZE];
1480
1481         freshest = NULL;
1482         ITERATE_RDEV(mddev,rdev,tmp)
1483                 switch (super_types[mddev->major_version].
1484                         load_super(rdev, freshest, mddev->minor_version)) {
1485                 case 1:
1486                         freshest = rdev;
1487                         break;
1488                 case 0:
1489                         break;
1490                 default:
1491                         printk( KERN_ERR \
1492                                 "md: fatal superblock inconsistency in %s"
1493                                 " -- removing from array\n",
1494                                 bdevname(rdev->bdev,b));
1495                         kick_rdev_from_array(rdev);
1496                 }
1497
1498
1499         super_types[mddev->major_version].
1500                 validate_super(mddev, freshest);
1501
1502         i = 0;
1503         ITERATE_RDEV(mddev,rdev,tmp) {
1504                 if (rdev != freshest)
1505                         if (super_types[mddev->major_version].
1506                             validate_super(mddev, rdev)) {
1507                                 printk(KERN_WARNING "md: kicking non-fresh %s"
1508                                         " from array!\n",
1509                                         bdevname(rdev->bdev,b));
1510                                 kick_rdev_from_array(rdev);
1511                                 continue;
1512                         }
1513                 if (mddev->level == LEVEL_MULTIPATH) {
1514                         rdev->desc_nr = i++;
1515                         rdev->raid_disk = rdev->desc_nr;
1516                         rdev->in_sync = 1;
1517                 }
1518         }
1519
1520
1521
1522         if (mddev->recovery_cp != MaxSector &&
1523             mddev->level >= 1)
1524                 printk(KERN_ERR "md: %s: raid array is not clean"
1525                        " -- starting background reconstruction\n",
1526                        mdname(mddev));
1527
1528 }
1529
1530 int mdp_major = 0;
1531
1532 static struct kobject *md_probe(dev_t dev, int *part, void *data)
1533 {
1534         static DECLARE_MUTEX(disks_sem);
1535         mddev_t *mddev = mddev_find(dev);
1536         struct gendisk *disk;
1537         int partitioned = (MAJOR(dev) != MD_MAJOR);
1538         int shift = partitioned ? MdpMinorShift : 0;
1539         int unit = MINOR(dev) >> shift;
1540
1541         if (!mddev)
1542                 return NULL;
1543
1544         down(&disks_sem);
1545         if (mddev->gendisk) {
1546                 up(&disks_sem);
1547                 mddev_put(mddev);
1548                 return NULL;
1549         }
1550         disk = alloc_disk(1 << shift);
1551         if (!disk) {
1552                 up(&disks_sem);
1553                 mddev_put(mddev);
1554                 return NULL;
1555         }
1556         disk->major = MAJOR(dev);
1557         disk->first_minor = unit << shift;
1558         if (partitioned) {
1559                 sprintf(disk->disk_name, "md_d%d", unit);
1560                 sprintf(disk->devfs_name, "md/d%d", unit);
1561         } else {
1562                 sprintf(disk->disk_name, "md%d", unit);
1563                 sprintf(disk->devfs_name, "md/%d", unit);
1564         }
1565         disk->fops = &md_fops;
1566         disk->private_data = mddev;
1567         disk->queue = mddev->queue;
1568         add_disk(disk);
1569         mddev->gendisk = disk;
1570         up(&disks_sem);
1571         return NULL;
1572 }
1573
1574 void md_wakeup_thread(mdk_thread_t *thread);
1575
1576 static void md_safemode_timeout(unsigned long data)
1577 {
1578         mddev_t *mddev = (mddev_t *) data;
1579
1580         mddev->safemode = 1;
1581         md_wakeup_thread(mddev->thread);
1582 }
1583
1584
1585 static int do_md_run(mddev_t * mddev)
1586 {
1587         int pnum, err;
1588         int chunk_size;
1589         struct list_head *tmp;
1590         mdk_rdev_t *rdev;
1591         struct gendisk *disk;
1592         char b[BDEVNAME_SIZE];
1593
1594         if (list_empty(&mddev->disks))
1595                 /* cannot run an array with no devices.. */
1596                 return -EINVAL;
1597
1598         if (mddev->pers)
1599                 return -EBUSY;
1600
1601         /*
1602          * Analyze all RAID superblock(s)
1603          */
1604         if (!mddev->raid_disks)
1605                 analyze_sbs(mddev);
1606
1607         chunk_size = mddev->chunk_size;
1608         pnum = level_to_pers(mddev->level);
1609
1610         if ((pnum != MULTIPATH) && (pnum != RAID1)) {
1611                 if (!chunk_size) {
1612                         /*
1613                          * 'default chunksize' in the old md code used to
1614                          * be PAGE_SIZE, baaad.
1615                          * we abort here to be on the safe side. We don't
1616                          * want to continue the bad practice.
1617                          */
1618                         printk(KERN_ERR
1619                                 "no chunksize specified, see 'man raidtab'\n");
1620                         return -EINVAL;
1621                 }
1622                 if (chunk_size > MAX_CHUNK_SIZE) {
1623                         printk(KERN_ERR "too big chunk_size: %d > %d\n",
1624                                 chunk_size, MAX_CHUNK_SIZE);
1625                         return -EINVAL;
1626                 }
1627                 /*
1628                  * chunk-size has to be a power of 2 and multiples of PAGE_SIZE
1629                  */
1630                 if ( (1 << ffz(~chunk_size)) != chunk_size) {
1631                         printk(KERN_ERR "chunk_size of %d not valid\n", chunk_size);
1632                         return -EINVAL;
1633                 }
1634                 if (chunk_size < PAGE_SIZE) {
1635                         printk(KERN_ERR "too small chunk_size: %d < %ld\n",
1636                                 chunk_size, PAGE_SIZE);
1637                         return -EINVAL;
1638                 }
1639
1640                 /* devices must have minimum size of one chunk */
1641                 ITERATE_RDEV(mddev,rdev,tmp) {
1642                         if (rdev->faulty)
1643                                 continue;
1644                         if (rdev->size < chunk_size / 1024) {
1645                                 printk(KERN_WARNING
1646                                         "md: Dev %s smaller than chunk_size:"
1647                                         " %lluk < %dk\n",
1648                                         bdevname(rdev->bdev,b),
1649                                         (unsigned long long)rdev->size,
1650                                         chunk_size / 1024);
1651                                 return -EINVAL;
1652                         }
1653                 }
1654         }
1655
1656 #ifdef CONFIG_KMOD
1657         if (!pers[pnum])
1658         {
1659                 request_module("md-personality-%d", pnum);
1660         }
1661 #endif
1662
1663         /*
1664          * Drop all container device buffers, from now on
1665          * the only valid external interface is through the md
1666          * device.
1667          * Also find largest hardsector size
1668          */
1669         ITERATE_RDEV(mddev,rdev,tmp) {
1670                 if (rdev->faulty)
1671                         continue;
1672                 sync_blockdev(rdev->bdev);
1673                 invalidate_bdev(rdev->bdev, 0);
1674         }
1675
1676         md_probe(mddev->unit, NULL, NULL);
1677         disk = mddev->gendisk;
1678         if (!disk)
1679                 return -ENOMEM;
1680
1681         spin_lock(&pers_lock);
1682         if (!pers[pnum] || !try_module_get(pers[pnum]->owner)) {
1683                 spin_unlock(&pers_lock);
1684                 printk(KERN_WARNING "md: personality %d is not loaded!\n",
1685                        pnum);
1686                 return -EINVAL;
1687         }
1688
1689         mddev->pers = pers[pnum];
1690         spin_unlock(&pers_lock);
1691
1692         mddev->resync_max_sectors = mddev->size << 1; /* may be over-ridden by personality */
1693
1694         /* before we start the array running, initialise the bitmap */
1695         err = bitmap_create(mddev);
1696         if (err)
1697                 printk(KERN_ERR "%s: failed to create bitmap (%d)\n",
1698                         mdname(mddev), err);
1699         else
1700                 err = mddev->pers->run(mddev);
1701         if (err) {
1702                 printk(KERN_ERR "md: pers->run() failed ...\n");
1703                 module_put(mddev->pers->owner);
1704                 mddev->pers = NULL;
1705                 bitmap_destroy(mddev);
1706                 return err;
1707         }
1708         atomic_set(&mddev->writes_pending,0);
1709         mddev->safemode = 0;
1710         mddev->safemode_timer.function = md_safemode_timeout;
1711         mddev->safemode_timer.data = (unsigned long) mddev;
1712         mddev->safemode_delay = (20 * HZ)/1000 +1; /* 20 msec delay */
1713         mddev->in_sync = 1;
1714
1715         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
1716         md_wakeup_thread(mddev->thread);
1717
1718         if (mddev->sb_dirty)
1719                 md_update_sb(mddev);
1720
1721         set_capacity(disk, mddev->array_size<<1);
1722
1723         /* If we call blk_queue_make_request here, it will
1724          * re-initialise max_sectors etc which may have been
1725          * refined inside -> run.  So just set the bits we need to set.
1726          * Most initialisation happended when we called
1727          * blk_queue_make_request(..., md_fail_request)
1728          * earlier.
1729          */
1730         mddev->queue->queuedata = mddev;
1731         mddev->queue->make_request_fn = mddev->pers->make_request;
1732
1733         mddev->changed = 1;
1734         return 0;
1735 }
1736
1737 static int restart_array(mddev_t *mddev)
1738 {
1739         struct gendisk *disk = mddev->gendisk;
1740         int err;
1741
1742         /*
1743          * Complain if it has no devices
1744          */
1745         err = -ENXIO;
1746         if (list_empty(&mddev->disks))
1747                 goto out;
1748
1749         if (mddev->pers) {
1750                 err = -EBUSY;
1751                 if (!mddev->ro)
1752                         goto out;
1753
1754                 mddev->safemode = 0;
1755                 mddev->ro = 0;
1756                 set_disk_ro(disk, 0);
1757
1758                 printk(KERN_INFO "md: %s switched to read-write mode.\n",
1759                         mdname(mddev));
1760                 /*
1761                  * Kick recovery or resync if necessary
1762                  */
1763                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
1764                 md_wakeup_thread(mddev->thread);
1765                 err = 0;
1766         } else {
1767                 printk(KERN_ERR "md: %s has no personality assigned.\n",
1768                         mdname(mddev));
1769                 err = -EINVAL;
1770         }
1771
1772 out:
1773         return err;
1774 }
1775
1776 static int do_md_stop(mddev_t * mddev, int ro)
1777 {
1778         int err = 0;
1779         struct gendisk *disk = mddev->gendisk;
1780
1781         if (mddev->pers) {
1782                 if (atomic_read(&mddev->active)>2) {
1783                         printk("md: %s still in use.\n",mdname(mddev));
1784                         return -EBUSY;
1785                 }
1786
1787                 if (mddev->sync_thread) {
1788                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
1789                         md_unregister_thread(mddev->sync_thread);
1790                         mddev->sync_thread = NULL;
1791                 }
1792
1793                 del_timer_sync(&mddev->safemode_timer);
1794
1795                 invalidate_partition(disk, 0);
1796
1797                 if (ro) {
1798                         err  = -ENXIO;
1799                         if (mddev->ro)
1800                                 goto out;
1801                         mddev->ro = 1;
1802                 } else {
1803                         bitmap_flush(mddev);
1804                         wait_event(mddev->sb_wait, atomic_read(&mddev->pending_writes)==0);
1805                         if (mddev->ro)
1806                                 set_disk_ro(disk, 0);
1807                         blk_queue_make_request(mddev->queue, md_fail_request);
1808                         mddev->pers->stop(mddev);
1809                         module_put(mddev->pers->owner);
1810                         mddev->pers = NULL;
1811                         if (mddev->ro)
1812                                 mddev->ro = 0;
1813                 }
1814                 if (!mddev->in_sync) {
1815                         /* mark array as shutdown cleanly */
1816                         mddev->in_sync = 1;
1817                         md_update_sb(mddev);
1818                 }
1819                 if (ro)
1820                         set_disk_ro(disk, 1);
1821         }
1822
1823         bitmap_destroy(mddev);
1824         if (mddev->bitmap_file) {
1825                 atomic_set(&mddev->bitmap_file->f_dentry->d_inode->i_writecount, 1);
1826                 fput(mddev->bitmap_file);
1827                 mddev->bitmap_file = NULL;
1828         }
1829         mddev->bitmap_offset = 0;
1830
1831         /*
1832          * Free resources if final stop
1833          */
1834         if (!ro) {
1835                 struct gendisk *disk;
1836                 printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
1837
1838                 export_array(mddev);
1839
1840                 mddev->array_size = 0;
1841                 disk = mddev->gendisk;
1842                 if (disk)
1843                         set_capacity(disk, 0);
1844                 mddev->changed = 1;
1845         } else
1846                 printk(KERN_INFO "md: %s switched to read-only mode.\n",
1847                         mdname(mddev));
1848         err = 0;
1849 out:
1850         return err;
1851 }
1852
1853 static void autorun_array(mddev_t *mddev)
1854 {
1855         mdk_rdev_t *rdev;
1856         struct list_head *tmp;
1857         int err;
1858
1859         if (list_empty(&mddev->disks))
1860                 return;
1861
1862         printk(KERN_INFO "md: running: ");
1863
1864         ITERATE_RDEV(mddev,rdev,tmp) {
1865                 char b[BDEVNAME_SIZE];
1866                 printk("<%s>", bdevname(rdev->bdev,b));
1867         }
1868         printk("\n");
1869
1870         err = do_md_run (mddev);
1871         if (err) {
1872                 printk(KERN_WARNING "md: do_md_run() returned %d\n", err);
1873                 do_md_stop (mddev, 0);
1874         }
1875 }
1876
1877 /*
1878  * lets try to run arrays based on all disks that have arrived
1879  * until now. (those are in pending_raid_disks)
1880  *
1881  * the method: pick the first pending disk, collect all disks with
1882  * the same UUID, remove all from the pending list and put them into
1883  * the 'same_array' list. Then order this list based on superblock
1884  * update time (freshest comes first), kick out 'old' disks and
1885  * compare superblocks. If everything's fine then run it.
1886  *
1887  * If "unit" is allocated, then bump its reference count
1888  */
1889 static void autorun_devices(int part)
1890 {
1891         struct list_head candidates;
1892         struct list_head *tmp;
1893         mdk_rdev_t *rdev0, *rdev;
1894         mddev_t *mddev;
1895         char b[BDEVNAME_SIZE];
1896
1897         printk(KERN_INFO "md: autorun ...\n");
1898         while (!list_empty(&pending_raid_disks)) {
1899                 dev_t dev;
1900                 rdev0 = list_entry(pending_raid_disks.next,
1901                                          mdk_rdev_t, same_set);
1902
1903                 printk(KERN_INFO "md: considering %s ...\n",
1904                         bdevname(rdev0->bdev,b));
1905                 INIT_LIST_HEAD(&candidates);
1906                 ITERATE_RDEV_PENDING(rdev,tmp)
1907                         if (super_90_load(rdev, rdev0, 0) >= 0) {
1908                                 printk(KERN_INFO "md:  adding %s ...\n",
1909                                         bdevname(rdev->bdev,b));
1910                                 list_move(&rdev->same_set, &candidates);
1911                         }
1912                 /*
1913                  * now we have a set of devices, with all of them having
1914                  * mostly sane superblocks. It's time to allocate the
1915                  * mddev.
1916                  */
1917                 if (rdev0->preferred_minor < 0 || rdev0->preferred_minor >= MAX_MD_DEVS) {
1918                         printk(KERN_INFO "md: unit number in %s is bad: %d\n",
1919                                bdevname(rdev0->bdev, b), rdev0->preferred_minor);
1920                         break;
1921                 }
1922                 if (part)
1923                         dev = MKDEV(mdp_major,
1924                                     rdev0->preferred_minor << MdpMinorShift);
1925                 else
1926                         dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
1927
1928                 md_probe(dev, NULL, NULL);
1929                 mddev = mddev_find(dev);
1930                 if (!mddev) {
1931                         printk(KERN_ERR
1932                                 "md: cannot allocate memory for md drive.\n");
1933                         break;
1934                 }
1935                 if (mddev_lock(mddev))
1936                         printk(KERN_WARNING "md: %s locked, cannot run\n",
1937                                mdname(mddev));
1938                 else if (mddev->raid_disks || mddev->major_version
1939                          || !list_empty(&mddev->disks)) {
1940                         printk(KERN_WARNING
1941                                 "md: %s already running, cannot run %s\n",
1942                                 mdname(mddev), bdevname(rdev0->bdev,b));
1943                         mddev_unlock(mddev);
1944                 } else {
1945                         printk(KERN_INFO "md: created %s\n", mdname(mddev));
1946                         ITERATE_RDEV_GENERIC(candidates,rdev,tmp) {
1947                                 list_del_init(&rdev->same_set);
1948                                 if (bind_rdev_to_array(rdev, mddev))
1949                                         export_rdev(rdev);
1950                         }
1951                         autorun_array(mddev);
1952                         mddev_unlock(mddev);
1953                 }
1954                 /* on success, candidates will be empty, on error
1955                  * it won't...
1956                  */
1957                 ITERATE_RDEV_GENERIC(candidates,rdev,tmp)
1958                         export_rdev(rdev);
1959                 mddev_put(mddev);
1960         }
1961         printk(KERN_INFO "md: ... autorun DONE.\n");
1962 }
1963
1964 /*
1965  * import RAID devices based on one partition
1966  * if possible, the array gets run as well.
1967  */
1968
1969 static int autostart_array(dev_t startdev)
1970 {
1971         char b[BDEVNAME_SIZE];
1972         int err = -EINVAL, i;
1973         mdp_super_t *sb = NULL;
1974         mdk_rdev_t *start_rdev = NULL, *rdev;
1975
1976         start_rdev = md_import_device(startdev, 0, 0);
1977         if (IS_ERR(start_rdev))
1978                 return err;
1979
1980
1981         /* NOTE: this can only work for 0.90.0 superblocks */
1982         sb = (mdp_super_t*)page_address(start_rdev->sb_page);
1983         if (sb->major_version != 0 ||
1984             sb->minor_version != 90 ) {
1985                 printk(KERN_WARNING "md: can only autostart 0.90.0 arrays\n");
1986                 export_rdev(start_rdev);
1987                 return err;
1988         }
1989
1990         if (start_rdev->faulty) {
1991                 printk(KERN_WARNING
1992                         "md: can not autostart based on faulty %s!\n",
1993                         bdevname(start_rdev->bdev,b));
1994                 export_rdev(start_rdev);
1995                 return err;
1996         }
1997         list_add(&start_rdev->same_set, &pending_raid_disks);
1998
1999         for (i = 0; i < MD_SB_DISKS; i++) {
2000                 mdp_disk_t *desc = sb->disks + i;
2001                 dev_t dev = MKDEV(desc->major, desc->minor);
2002
2003                 if (!dev)
2004                         continue;
2005                 if (dev == startdev)
2006                         continue;
2007                 if (MAJOR(dev) != desc->major || MINOR(dev) != desc->minor)
2008                         continue;
2009                 rdev = md_import_device(dev, 0, 0);
2010                 if (IS_ERR(rdev))
2011                         continue;
2012
2013                 list_add(&rdev->same_set, &pending_raid_disks);
2014         }
2015
2016         /*
2017          * possibly return codes
2018          */
2019         autorun_devices(0);
2020         return 0;
2021
2022 }
2023
2024
2025 static int get_version(void __user * arg)
2026 {
2027         mdu_version_t ver;
2028
2029         ver.major = MD_MAJOR_VERSION;
2030         ver.minor = MD_MINOR_VERSION;
2031         ver.patchlevel = MD_PATCHLEVEL_VERSION;
2032
2033         if (copy_to_user(arg, &ver, sizeof(ver)))
2034                 return -EFAULT;
2035
2036         return 0;
2037 }
2038
2039 static int get_array_info(mddev_t * mddev, void __user * arg)
2040 {
2041         mdu_array_info_t info;
2042         int nr,working,active,failed,spare;
2043         mdk_rdev_t *rdev;
2044         struct list_head *tmp;
2045
2046         nr=working=active=failed=spare=0;
2047         ITERATE_RDEV(mddev,rdev,tmp) {
2048                 nr++;
2049                 if (rdev->faulty)
2050                         failed++;
2051                 else {
2052                         working++;
2053                         if (rdev->in_sync)
2054                                 active++;
2055                         else
2056                                 spare++;
2057                 }
2058         }
2059
2060         info.major_version = mddev->major_version;
2061         info.minor_version = mddev->minor_version;
2062         info.patch_version = MD_PATCHLEVEL_VERSION;
2063         info.ctime         = mddev->ctime;
2064         info.level         = mddev->level;
2065         info.size          = mddev->size;
2066         info.nr_disks      = nr;
2067         info.raid_disks    = mddev->raid_disks;
2068         info.md_minor      = mddev->md_minor;
2069         info.not_persistent= !mddev->persistent;
2070
2071         info.utime         = mddev->utime;
2072         info.state         = 0;
2073         if (mddev->in_sync)
2074                 info.state = (1<<MD_SB_CLEAN);
2075         info.active_disks  = active;
2076         info.working_disks = working;
2077         info.failed_disks  = failed;
2078         info.spare_disks   = spare;
2079
2080         info.layout        = mddev->layout;
2081         info.chunk_size    = mddev->chunk_size;
2082
2083         if (copy_to_user(arg, &info, sizeof(info)))
2084                 return -EFAULT;
2085
2086         return 0;
2087 }
2088
2089 static int get_bitmap_file(mddev_t * mddev, void * arg)
2090 {
2091         mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
2092         char *ptr, *buf = NULL;
2093         int err = -ENOMEM;
2094
2095         file = kmalloc(sizeof(*file), GFP_KERNEL);
2096         if (!file)
2097                 goto out;
2098
2099         /* bitmap disabled, zero the first byte and copy out */
2100         if (!mddev->bitmap || !mddev->bitmap->file) {
2101                 file->pathname[0] = '\0';
2102                 goto copy_out;
2103         }
2104
2105         buf = kmalloc(sizeof(file->pathname), GFP_KERNEL);
2106         if (!buf)
2107                 goto out;
2108
2109         ptr = file_path(mddev->bitmap->file, buf, sizeof(file->pathname));
2110         if (!ptr)
2111                 goto out;
2112
2113         strcpy(file->pathname, ptr);
2114
2115 copy_out:
2116         err = 0;
2117         if (copy_to_user(arg, file, sizeof(*file)))
2118                 err = -EFAULT;
2119 out:
2120         kfree(buf);
2121         kfree(file);
2122         return err;
2123 }
2124
2125 static int get_disk_info(mddev_t * mddev, void __user * arg)
2126 {
2127         mdu_disk_info_t info;
2128         unsigned int nr;
2129         mdk_rdev_t *rdev;
2130
2131         if (copy_from_user(&info, arg, sizeof(info)))
2132                 return -EFAULT;
2133
2134         nr = info.number;
2135
2136         rdev = find_rdev_nr(mddev, nr);
2137         if (rdev) {
2138                 info.major = MAJOR(rdev->bdev->bd_dev);
2139                 info.minor = MINOR(rdev->bdev->bd_dev);
2140                 info.raid_disk = rdev->raid_disk;
2141                 info.state = 0;
2142                 if (rdev->faulty)
2143                         info.state |= (1<<MD_DISK_FAULTY);
2144                 else if (rdev->in_sync) {
2145                         info.state |= (1<<MD_DISK_ACTIVE);
2146                         info.state |= (1<<MD_DISK_SYNC);
2147                 }
2148         } else {
2149                 info.major = info.minor = 0;
2150                 info.raid_disk = -1;
2151                 info.state = (1<<MD_DISK_REMOVED);
2152         }
2153
2154         if (copy_to_user(arg, &info, sizeof(info)))
2155                 return -EFAULT;
2156
2157         return 0;
2158 }
2159
2160 static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
2161 {
2162         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
2163         mdk_rdev_t *rdev;
2164         dev_t dev = MKDEV(info->major,info->minor);
2165
2166         if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
2167                 return -EOVERFLOW;
2168
2169         if (!mddev->raid_disks) {
2170                 int err;
2171                 /* expecting a device which has a superblock */
2172                 rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
2173                 if (IS_ERR(rdev)) {
2174                         printk(KERN_WARNING
2175                                 "md: md_import_device returned %ld\n",
2176                                 PTR_ERR(rdev));
2177                         return PTR_ERR(rdev);
2178                 }
2179                 if (!list_empty(&mddev->disks)) {
2180                         mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
2181                                                         mdk_rdev_t, same_set);
2182                         int err = super_types[mddev->major_version]
2183                                 .load_super(rdev, rdev0, mddev->minor_version);
2184                         if (err < 0) {
2185                                 printk(KERN_WARNING
2186                                         "md: %s has different UUID to %s\n",
2187                                         bdevname(rdev->bdev,b),
2188                                         bdevname(rdev0->bdev,b2));
2189                                 export_rdev(rdev);
2190                                 return -EINVAL;
2191                         }
2192                 }
2193                 err = bind_rdev_to_array(rdev, mddev);
2194                 if (err)
2195                         export_rdev(rdev);
2196                 return err;
2197         }
2198
2199         /*
2200          * add_new_disk can be used once the array is assembled
2201          * to add "hot spares".  They must already have a superblock
2202          * written
2203          */
2204         if (mddev->pers) {
2205                 int err;
2206                 if (!mddev->pers->hot_add_disk) {
2207                         printk(KERN_WARNING
2208                                 "%s: personality does not support diskops!\n",
2209                                mdname(mddev));
2210                         return -EINVAL;
2211                 }
2212                 rdev = md_import_device(dev, mddev->major_version,
2213                                         mddev->minor_version);
2214                 if (IS_ERR(rdev)) {
2215                         printk(KERN_WARNING
2216                                 "md: md_import_device returned %ld\n",
2217                                 PTR_ERR(rdev));
2218                         return PTR_ERR(rdev);
2219                 }
2220                 /* set save_raid_disk if appropriate */
2221                 if (!mddev->persistent) {
2222                         if (info->state & (1<<MD_DISK_SYNC)  &&
2223                             info->raid_disk < mddev->raid_disks)
2224                                 rdev->raid_disk = info->raid_disk;
2225                         else
2226                                 rdev->raid_disk = -1;
2227                 } else
2228                         super_types[mddev->major_version].
2229                                 validate_super(mddev, rdev);
2230                 rdev->saved_raid_disk = rdev->raid_disk;
2231
2232                 rdev->in_sync = 0; /* just to be sure */
2233                 rdev->raid_disk = -1;
2234                 err = bind_rdev_to_array(rdev, mddev);
2235                 if (err)
2236                         export_rdev(rdev);
2237
2238                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2239                 md_wakeup_thread(mddev->thread);
2240                 return err;
2241         }
2242
2243         /* otherwise, add_new_disk is only allowed
2244          * for major_version==0 superblocks
2245          */
2246         if (mddev->major_version != 0) {
2247                 printk(KERN_WARNING "%s: ADD_NEW_DISK not supported\n",
2248                        mdname(mddev));
2249                 return -EINVAL;
2250         }
2251
2252         if (!(info->state & (1<<MD_DISK_FAULTY))) {
2253                 int err;
2254                 rdev = md_import_device (dev, -1, 0);
2255                 if (IS_ERR(rdev)) {
2256                         printk(KERN_WARNING
2257                                 "md: error, md_import_device() returned %ld\n",
2258                                 PTR_ERR(rdev));
2259                         return PTR_ERR(rdev);
2260                 }
2261                 rdev->desc_nr = info->number;
2262                 if (info->raid_disk < mddev->raid_disks)
2263                         rdev->raid_disk = info->raid_disk;
2264                 else
2265                         rdev->raid_disk = -1;
2266
2267                 rdev->faulty = 0;
2268                 if (rdev->raid_disk < mddev->raid_disks)
2269                         rdev->in_sync = (info->state & (1<<MD_DISK_SYNC));
2270                 else
2271                         rdev->in_sync = 0;
2272
2273                 err = bind_rdev_to_array(rdev, mddev);
2274                 if (err) {
2275                         export_rdev(rdev);
2276                         return err;
2277                 }
2278
2279                 if (!mddev->persistent) {
2280                         printk(KERN_INFO "md: nonpersistent superblock ...\n");
2281                         rdev->sb_offset = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
2282                 } else
2283                         rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
2284                 rdev->size = calc_dev_size(rdev, mddev->chunk_size);
2285
2286                 if (!mddev->size || (mddev->size > rdev->size))
2287                         mddev->size = rdev->size;
2288         }
2289
2290         return 0;
2291 }
2292
2293 static int hot_remove_disk(mddev_t * mddev, dev_t dev)
2294 {
2295         char b[BDEVNAME_SIZE];
2296         mdk_rdev_t *rdev;
2297
2298         if (!mddev->pers)
2299                 return -ENODEV;
2300
2301         rdev = find_rdev(mddev, dev);
2302         if (!rdev)
2303                 return -ENXIO;
2304
2305         if (rdev->raid_disk >= 0)
2306                 goto busy;
2307
2308         kick_rdev_from_array(rdev);
2309         md_update_sb(mddev);
2310
2311         return 0;
2312 busy:
2313         printk(KERN_WARNING "md: cannot remove active disk %s from %s ... \n",
2314                 bdevname(rdev->bdev,b), mdname(mddev));
2315         return -EBUSY;
2316 }
2317
2318 static int hot_add_disk(mddev_t * mddev, dev_t dev)
2319 {
2320         char b[BDEVNAME_SIZE];
2321         int err;
2322         unsigned int size;
2323         mdk_rdev_t *rdev;
2324
2325         if (!mddev->pers)
2326                 return -ENODEV;
2327
2328         if (mddev->major_version != 0) {
2329                 printk(KERN_WARNING "%s: HOT_ADD may only be used with"
2330                         " version-0 superblocks.\n",
2331                         mdname(mddev));
2332                 return -EINVAL;
2333         }
2334         if (!mddev->pers->hot_add_disk) {
2335                 printk(KERN_WARNING
2336                         "%s: personality does not support diskops!\n",
2337                         mdname(mddev));
2338                 return -EINVAL;
2339         }
2340
2341         rdev = md_import_device (dev, -1, 0);
2342         if (IS_ERR(rdev)) {
2343                 printk(KERN_WARNING
2344                         "md: error, md_import_device() returned %ld\n",
2345                         PTR_ERR(rdev));
2346                 return -EINVAL;
2347         }
2348
2349         if (mddev->persistent)
2350                 rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
2351         else
2352                 rdev->sb_offset =
2353                         rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
2354
2355         size = calc_dev_size(rdev, mddev->chunk_size);
2356         rdev->size = size;
2357
2358         if (size < mddev->size) {
2359                 printk(KERN_WARNING
2360                         "%s: disk size %llu blocks < array size %llu\n",
2361                         mdname(mddev), (unsigned long long)size,
2362                         (unsigned long long)mddev->size);
2363                 err = -ENOSPC;
2364                 goto abort_export;
2365         }
2366
2367         if (rdev->faulty) {
2368                 printk(KERN_WARNING
2369                         "md: can not hot-add faulty %s disk to %s!\n",
2370                         bdevname(rdev->bdev,b), mdname(mddev));
2371                 err = -EINVAL;
2372                 goto abort_export;
2373         }
2374         rdev->in_sync = 0;
2375         rdev->desc_nr = -1;
2376         bind_rdev_to_array(rdev, mddev);
2377
2378         /*
2379          * The rest should better be atomic, we can have disk failures
2380          * noticed in interrupt contexts ...
2381          */
2382
2383         if (rdev->desc_nr == mddev->max_disks) {
2384                 printk(KERN_WARNING "%s: can not hot-add to full array!\n",
2385                         mdname(mddev));
2386                 err = -EBUSY;
2387                 goto abort_unbind_export;
2388         }
2389
2390         rdev->raid_disk = -1;
2391
2392         md_update_sb(mddev);
2393
2394         /*
2395          * Kick recovery, maybe this spare has to be added to the
2396          * array immediately.
2397          */
2398         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2399         md_wakeup_thread(mddev->thread);
2400
2401         return 0;
2402
2403 abort_unbind_export:
2404         unbind_rdev_from_array(rdev);
2405
2406 abort_export:
2407         export_rdev(rdev);
2408         return err;
2409 }
2410
2411 /* similar to deny_write_access, but accounts for our holding a reference
2412  * to the file ourselves */
2413 static int deny_bitmap_write_access(struct file * file)
2414 {
2415         struct inode *inode = file->f_mapping->host;
2416
2417         spin_lock(&inode->i_lock);
2418         if (atomic_read(&inode->i_writecount) > 1) {
2419                 spin_unlock(&inode->i_lock);
2420                 return -ETXTBSY;
2421         }
2422         atomic_set(&inode->i_writecount, -1);
2423         spin_unlock(&inode->i_lock);
2424
2425         return 0;
2426 }
2427
2428 static int set_bitmap_file(mddev_t *mddev, int fd)
2429 {
2430         int err;
2431
2432         if (mddev->pers)
2433                 return -EBUSY;
2434
2435         mddev->bitmap_file = fget(fd);
2436
2437         if (mddev->bitmap_file == NULL) {
2438                 printk(KERN_ERR "%s: error: failed to get bitmap file\n",
2439                         mdname(mddev));
2440                 return -EBADF;
2441         }
2442
2443         err = deny_bitmap_write_access(mddev->bitmap_file);
2444         if (err) {
2445                 printk(KERN_ERR "%s: error: bitmap file is already in use\n",
2446                         mdname(mddev));
2447                 fput(mddev->bitmap_file);
2448                 mddev->bitmap_file = NULL;
2449         } else
2450                 mddev->bitmap_offset = 0; /* file overrides offset */
2451         return err;
2452 }
2453
2454 /*
2455  * set_array_info is used two different ways
2456  * The original usage is when creating a new array.
2457  * In this usage, raid_disks is > 0 and it together with
2458  *  level, size, not_persistent,layout,chunksize determine the
2459  *  shape of the array.
2460  *  This will always create an array with a type-0.90.0 superblock.
2461  * The newer usage is when assembling an array.
2462  *  In this case raid_disks will be 0, and the major_version field is
2463  *  use to determine which style super-blocks are to be found on the devices.
2464  *  The minor and patch _version numbers are also kept incase the
2465  *  super_block handler wishes to interpret them.
2466  */
2467 static int set_array_info(mddev_t * mddev, mdu_array_info_t *info)
2468 {
2469
2470         if (info->raid_disks == 0) {
2471                 /* just setting version number for superblock loading */
2472                 if (info->major_version < 0 ||
2473                     info->major_version >= sizeof(super_types)/sizeof(super_types[0]) ||
2474                     super_types[info->major_version].name == NULL) {
2475                         /* maybe try to auto-load a module? */
2476                         printk(KERN_INFO
2477                                 "md: superblock version %d not known\n",
2478                                 info->major_version);
2479                         return -EINVAL;
2480                 }
2481                 mddev->major_version = info->major_version;
2482                 mddev->minor_version = info->minor_version;
2483                 mddev->patch_version = info->patch_version;
2484                 return 0;
2485         }
2486         mddev->major_version = MD_MAJOR_VERSION;
2487         mddev->minor_version = MD_MINOR_VERSION;
2488         mddev->patch_version = MD_PATCHLEVEL_VERSION;
2489         mddev->ctime         = get_seconds();
2490
2491         mddev->level         = info->level;
2492         mddev->size          = info->size;
2493         mddev->raid_disks    = info->raid_disks;
2494         /* don't set md_minor, it is determined by which /dev/md* was
2495          * openned
2496          */
2497         if (info->state & (1<<MD_SB_CLEAN))
2498                 mddev->recovery_cp = MaxSector;
2499         else
2500                 mddev->recovery_cp = 0;
2501         mddev->persistent    = ! info->not_persistent;
2502
2503         mddev->layout        = info->layout;
2504         mddev->chunk_size    = info->chunk_size;
2505
2506         mddev->max_disks     = MD_SB_DISKS;
2507
2508         mddev->sb_dirty      = 1;
2509
2510         /*
2511          * Generate a 128 bit UUID
2512          */
2513         get_random_bytes(mddev->uuid, 16);
2514
2515         return 0;
2516 }
2517
2518 /*
2519  * update_array_info is used to change the configuration of an
2520  * on-line array.
2521  * The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
2522  * fields in the info are checked against the array.
2523  * Any differences that cannot be handled will cause an error.
2524  * Normally, only one change can be managed at a time.
2525  */
2526 static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
2527 {
2528         int rv = 0;
2529         int cnt = 0;
2530
2531         if (mddev->major_version != info->major_version ||
2532             mddev->minor_version != info->minor_version ||
2533 /*          mddev->patch_version != info->patch_version || */
2534             mddev->ctime         != info->ctime         ||
2535             mddev->level         != info->level         ||
2536 /*          mddev->layout        != info->layout        || */
2537             !mddev->persistent   != info->not_persistent||
2538             mddev->chunk_size    != info->chunk_size    )
2539                 return -EINVAL;
2540         /* Check there is only one change */
2541         if (mddev->size != info->size) cnt++;
2542         if (mddev->raid_disks != info->raid_disks) cnt++;
2543         if (mddev->layout != info->layout) cnt++;
2544         if (cnt == 0) return 0;
2545         if (cnt > 1) return -EINVAL;
2546
2547         if (mddev->layout != info->layout) {
2548                 /* Change layout
2549                  * we don't need to do anything at the md level, the
2550                  * personality will take care of it all.
2551                  */
2552                 if (mddev->pers->reconfig == NULL)
2553                         return -EINVAL;
2554                 else
2555                         return mddev->pers->reconfig(mddev, info->layout, -1);
2556         }
2557         if (mddev->size != info->size) {
2558                 mdk_rdev_t * rdev;
2559                 struct list_head *tmp;
2560                 if (mddev->pers->resize == NULL)
2561                         return -EINVAL;
2562                 /* The "size" is the amount of each device that is used.
2563                  * This can only make sense for arrays with redundancy.
2564                  * linear and raid0 always use whatever space is available
2565                  * We can only consider changing the size if no resync
2566                  * or reconstruction is happening, and if the new size
2567                  * is acceptable. It must fit before the sb_offset or,
2568                  * if that is <data_offset, it must fit before the
2569                  * size of each device.
2570                  * If size is zero, we find the largest size that fits.
2571                  */
2572                 if (mddev->sync_thread)
2573                         return -EBUSY;
2574                 ITERATE_RDEV(mddev,rdev,tmp) {
2575                         sector_t avail;
2576                         int fit = (info->size == 0);
2577                         if (rdev->sb_offset > rdev->data_offset)
2578                                 avail = (rdev->sb_offset*2) - rdev->data_offset;
2579                         else
2580                                 avail = get_capacity(rdev->bdev->bd_disk)
2581                                         - rdev->data_offset;
2582                         if (fit && (info->size == 0 || info->size > avail/2))
2583                                 info->size = avail/2;
2584                         if (avail < ((sector_t)info->size << 1))
2585                                 return -ENOSPC;
2586                 }
2587                 rv = mddev->pers->resize(mddev, (sector_t)info->size *2);
2588                 if (!rv) {
2589                         struct block_device *bdev;
2590
2591                         bdev = bdget_disk(mddev->gendisk, 0);
2592                         if (bdev) {
2593                                 down(&bdev->bd_inode->i_sem);
2594                                 i_size_write(bdev->bd_inode, mddev->array_size << 10);
2595                                 up(&bdev->bd_inode->i_sem);
2596                                 bdput(bdev);
2597                         }
2598                 }
2599         }
2600         if (mddev->raid_disks    != info->raid_disks) {
2601                 /* change the number of raid disks */
2602                 if (mddev->pers->reshape == NULL)
2603                         return -EINVAL;
2604                 if (info->raid_disks <= 0 ||
2605                     info->raid_disks >= mddev->max_disks)
2606                         return -EINVAL;
2607                 if (mddev->sync_thread)
2608                         return -EBUSY;
2609                 rv = mddev->pers->reshape(mddev, info->raid_disks);
2610                 if (!rv) {
2611                         struct block_device *bdev;
2612
2613                         bdev = bdget_disk(mddev->gendisk, 0);
2614                         if (bdev) {
2615                                 down(&bdev->bd_inode->i_sem);
2616                                 i_size_write(bdev->bd_inode, mddev->array_size << 10);
2617                                 up(&bdev->bd_inode->i_sem);
2618                                 bdput(bdev);
2619                         }
2620                 }
2621         }
2622         md_update_sb(mddev);
2623         return rv;
2624 }
2625
2626 static int set_disk_faulty(mddev_t *mddev, dev_t dev)
2627 {
2628         mdk_rdev_t *rdev;
2629
2630         if (mddev->pers == NULL)
2631                 return -ENODEV;
2632
2633         rdev = find_rdev(mddev, dev);
2634         if (!rdev)
2635                 return -ENODEV;
2636
2637         md_error(mddev, rdev);
2638         return 0;
2639 }
2640
2641 static int md_ioctl(struct inode *inode, struct file *file,
2642                         unsigned int cmd, unsigned long arg)
2643 {
2644         int err = 0;
2645         void __user *argp = (void __user *)arg;
2646         struct hd_geometry __user *loc = argp;
2647         mddev_t *mddev = NULL;
2648
2649         if (!capable(CAP_SYS_ADMIN))
2650                 return -EACCES;
2651
2652         /*
2653          * Commands dealing with the RAID driver but not any
2654          * particular array:
2655          */
2656         switch (cmd)
2657         {
2658                 case RAID_VERSION:
2659                         err = get_version(argp);
2660                         goto done;
2661
2662                 case PRINT_RAID_DEBUG:
2663                         err = 0;
2664                         md_print_devices();
2665                         goto done;
2666
2667 #ifndef MODULE
2668                 case RAID_AUTORUN:
2669                         err = 0;
2670                         autostart_arrays(arg);
2671                         goto done;
2672 #endif
2673                 default:;
2674         }
2675
2676         /*
2677          * Commands creating/starting a new array:
2678          */
2679
2680         mddev = inode->i_bdev->bd_disk->private_data;
2681
2682         if (!mddev) {
2683                 BUG();
2684                 goto abort;
2685         }
2686
2687
2688         if (cmd == START_ARRAY) {
2689                 /* START_ARRAY doesn't need to lock the array as autostart_array
2690                  * does the locking, and it could even be a different array
2691                  */
2692                 static int cnt = 3;
2693                 if (cnt > 0 ) {
2694                         printk(KERN_WARNING
2695                                "md: %s(pid %d) used deprecated START_ARRAY ioctl. "
2696                                "This will not be supported beyond 2.6\n",
2697                                current->comm, current->pid);
2698                         cnt--;
2699                 }
2700                 err = autostart_array(new_decode_dev(arg));
2701                 if (err) {
2702                         printk(KERN_WARNING "md: autostart failed!\n");
2703                         goto abort;
2704                 }
2705                 goto done;
2706         }
2707
2708         err = mddev_lock(mddev);
2709         if (err) {
2710                 printk(KERN_INFO
2711                         "md: ioctl lock interrupted, reason %d, cmd %d\n",
2712                         err, cmd);
2713                 goto abort;
2714         }
2715
2716         switch (cmd)
2717         {
2718                 case SET_ARRAY_INFO:
2719                         {
2720                                 mdu_array_info_t info;
2721                                 if (!arg)
2722                                         memset(&info, 0, sizeof(info));
2723                                 else if (copy_from_user(&info, argp, sizeof(info))) {
2724                                         err = -EFAULT;
2725                                         goto abort_unlock;
2726                                 }
2727                                 if (mddev->pers) {
2728                                         err = update_array_info(mddev, &info);
2729                                         if (err) {
2730                                                 printk(KERN_WARNING "md: couldn't update"
2731                                                        " array info. %d\n", err);
2732                                                 goto abort_unlock;
2733                                         }
2734                                         goto done_unlock;
2735                                 }
2736                                 if (!list_empty(&mddev->disks)) {
2737                                         printk(KERN_WARNING
2738                                                "md: array %s already has disks!\n",
2739                                                mdname(mddev));
2740                                         err = -EBUSY;
2741                                         goto abort_unlock;
2742                                 }
2743                                 if (mddev->raid_disks) {
2744                                         printk(KERN_WARNING
2745                                                "md: array %s already initialised!\n",
2746                                                mdname(mddev));
2747                                         err = -EBUSY;
2748                                         goto abort_unlock;
2749                                 }
2750                                 err = set_array_info(mddev, &info);
2751                                 if (err) {
2752                                         printk(KERN_WARNING "md: couldn't set"
2753                                                " array info. %d\n", err);
2754                                         goto abort_unlock;
2755                                 }
2756                         }
2757                         goto done_unlock;
2758
2759                 default:;
2760         }
2761
2762         /*
2763          * Commands querying/configuring an existing array:
2764          */
2765         /* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
2766          * RUN_ARRAY, and SET_BITMAP_FILE are allowed */
2767         if (!mddev->raid_disks && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
2768                         && cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE) {
2769                 err = -ENODEV;
2770                 goto abort_unlock;
2771         }
2772
2773         /*
2774          * Commands even a read-only array can execute:
2775          */
2776         switch (cmd)
2777         {
2778                 case GET_ARRAY_INFO:
2779                         err = get_array_info(mddev, argp);
2780                         goto done_unlock;
2781
2782                 case GET_BITMAP_FILE:
2783                         err = get_bitmap_file(mddev, (void *)arg);
2784                         goto done_unlock;
2785
2786                 case GET_DISK_INFO:
2787                         err = get_disk_info(mddev, argp);
2788                         goto done_unlock;
2789
2790                 case RESTART_ARRAY_RW:
2791                         err = restart_array(mddev);
2792                         goto done_unlock;
2793
2794                 case STOP_ARRAY:
2795                         err = do_md_stop (mddev, 0);
2796                         goto done_unlock;
2797
2798                 case STOP_ARRAY_RO:
2799                         err = do_md_stop (mddev, 1);
2800                         goto done_unlock;
2801
2802         /*
2803          * We have a problem here : there is no easy way to give a CHS
2804          * virtual geometry. We currently pretend that we have a 2 heads
2805          * 4 sectors (with a BIG number of cylinders...). This drives
2806          * dosfs just mad... ;-)
2807          */
2808                 case HDIO_GETGEO:
2809                         if (!loc) {
2810                                 err = -EINVAL;
2811                                 goto abort_unlock;
2812                         }
2813                         err = put_user (2, (char __user *) &loc->heads);
2814                         if (err)
2815                                 goto abort_unlock;
2816                         err = put_user (4, (char __user *) &loc->sectors);
2817                         if (err)
2818                                 goto abort_unlock;
2819                         err = put_user(get_capacity(mddev->gendisk)/8,
2820                                         (short __user *) &loc->cylinders);
2821                         if (err)
2822                                 goto abort_unlock;
2823                         err = put_user (get_start_sect(inode->i_bdev),
2824                                                 (long __user *) &loc->start);
2825                         goto done_unlock;
2826         }
2827
2828         /*
2829          * The remaining ioctls are changing the state of the
2830          * superblock, so we do not allow read-only arrays
2831          * here:
2832          */
2833         if (mddev->ro) {
2834                 err = -EROFS;
2835                 goto abort_unlock;
2836         }
2837
2838         switch (cmd)
2839         {
2840                 case ADD_NEW_DISK:
2841                 {
2842                         mdu_disk_info_t info;
2843                         if (copy_from_user(&info, argp, sizeof(info)))
2844                                 err = -EFAULT;
2845                         else
2846                                 err = add_new_disk(mddev, &info);
2847                         goto done_unlock;
2848                 }
2849
2850                 case HOT_REMOVE_DISK:
2851                         err = hot_remove_disk(mddev, new_decode_dev(arg));
2852                         goto done_unlock;
2853
2854                 case HOT_ADD_DISK:
2855                         err = hot_add_disk(mddev, new_decode_dev(arg));
2856                         goto done_unlock;
2857
2858                 case SET_DISK_FAULTY:
2859                         err = set_disk_faulty(mddev, new_decode_dev(arg));
2860                         goto done_unlock;
2861
2862                 case RUN_ARRAY:
2863                         err = do_md_run (mddev);
2864                         goto done_unlock;
2865
2866                 case SET_BITMAP_FILE:
2867                         err = set_bitmap_file(mddev, (int)arg);
2868                         goto done_unlock;
2869
2870                 default:
2871                         if (_IOC_TYPE(cmd) == MD_MAJOR)
2872                                 printk(KERN_WARNING "md: %s(pid %d) used"
2873                                         " obsolete MD ioctl, upgrade your"
2874                                         " software to use new ictls.\n",
2875                                         current->comm, current->pid);
2876                         err = -EINVAL;
2877                         goto abort_unlock;
2878         }
2879
2880 done_unlock:
2881 abort_unlock:
2882         mddev_unlock(mddev);
2883
2884         return err;
2885 done:
2886         if (err)
2887                 MD_BUG();
2888 abort:
2889         return err;
2890 }
2891
2892 static int md_open(struct inode *inode, struct file *file)
2893 {
2894         /*
2895          * Succeed if we can lock the mddev, which confirms that
2896          * it isn't being stopped right now.
2897          */
2898         mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
2899         int err;
2900
2901         if ((err = mddev_lock(mddev)))
2902                 goto out;
2903
2904         err = 0;
2905         mddev_get(mddev);
2906         mddev_unlock(mddev);
2907
2908         check_disk_change(inode->i_bdev);
2909  out:
2910         return err;
2911 }
2912
2913 static int md_release(struct inode *inode, struct file * file)
2914 {
2915         mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
2916
2917         if (!mddev)
2918                 BUG();
2919         mddev_put(mddev);
2920
2921         return 0;
2922 }
2923
2924 static int md_media_changed(struct gendisk *disk)
2925 {
2926         mddev_t *mddev = disk->private_data;
2927
2928         return mddev->changed;
2929 }
2930
2931 static int md_revalidate(struct gendisk *disk)
2932 {
2933         mddev_t *mddev = disk->private_data;
2934
2935         mddev->changed = 0;
2936         return 0;
2937 }
2938 static struct block_device_operations md_fops =
2939 {
2940         .owner          = THIS_MODULE,
2941         .open           = md_open,
2942         .release        = md_release,
2943         .ioctl          = md_ioctl,
2944         .media_changed  = md_media_changed,
2945         .revalidate_disk= md_revalidate,
2946 };
2947
2948 static int md_thread(void * arg)
2949 {
2950         mdk_thread_t *thread = arg;
2951
2952         lock_kernel();
2953
2954         /*
2955          * Detach thread
2956          */
2957
2958         daemonize(thread->name, mdname(thread->mddev));
2959
2960         current->exit_signal = SIGCHLD;
2961         allow_signal(SIGKILL);
2962         thread->tsk = current;
2963
2964         /*
2965          * md_thread is a 'system-thread', it's priority should be very
2966          * high. We avoid resource deadlocks individually in each
2967          * raid personality. (RAID5 does preallocation) We also use RR and
2968          * the very same RT priority as kswapd, thus we will never get
2969          * into a priority inversion deadlock.
2970          *
2971          * we definitely have to have equal or higher priority than
2972          * bdflush, otherwise bdflush will deadlock if there are too
2973          * many dirty RAID5 blocks.
2974          */
2975         unlock_kernel();
2976
2977         complete(thread->event);
2978         while (thread->run) {
2979                 void (*run)(mddev_t *);
2980
2981                 wait_event_interruptible_timeout(thread->wqueue,
2982                                                  test_bit(THREAD_WAKEUP, &thread->flags),
2983                                                  thread->timeout);
2984                 try_to_freeze();
2985
2986                 clear_bit(THREAD_WAKEUP, &thread->flags);
2987
2988                 run = thread->run;
2989                 if (run)
2990                         run(thread->mddev);
2991
2992                 if (signal_pending(current))
2993                         flush_signals(current);
2994         }
2995         complete(thread->event);
2996         return 0;
2997 }
2998
2999 void md_wakeup_thread(mdk_thread_t *thread)
3000 {
3001         if (thread) {
3002                 dprintk("md: waking up MD thread %s.\n", thread->tsk->comm);
3003                 set_bit(THREAD_WAKEUP, &thread->flags);
3004                 wake_up(&thread->wqueue);
3005         }
3006 }
3007
3008 mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev,
3009                                  const char *name)
3010 {
3011         mdk_thread_t *thread;
3012         int ret;
3013         struct completion event;
3014
3015         thread = (mdk_thread_t *) kmalloc
3016                                 (sizeof(mdk_thread_t), GFP_KERNEL);
3017         if (!thread)
3018                 return NULL;
3019
3020         memset(thread, 0, sizeof(mdk_thread_t));
3021         init_waitqueue_head(&thread->wqueue);
3022
3023         init_completion(&event);
3024         thread->event = &event;
3025         thread->run = run;
3026         thread->mddev = mddev;
3027         thread->name = name;
3028         thread->timeout = MAX_SCHEDULE_TIMEOUT;
3029         ret = kernel_thread(md_thread, thread, 0);
3030         if (ret < 0) {
3031                 kfree(thread);
3032                 return NULL;
3033         }
3034         wait_for_completion(&event);
3035         return thread;
3036 }
3037
3038 void md_unregister_thread(mdk_thread_t *thread)
3039 {
3040         struct completion event;
3041
3042         init_completion(&event);
3043
3044         thread->event = &event;
3045
3046         /* As soon as ->run is set to NULL, the task could disappear,
3047          * so we need to hold tasklist_lock until we have sent the signal
3048          */
3049         dprintk("interrupting MD-thread pid %d\n", thread->tsk->pid);
3050         read_lock(&tasklist_lock);
3051         thread->run = NULL;
3052         send_sig(SIGKILL, thread->tsk, 1);
3053         read_unlock(&tasklist_lock);
3054         wait_for_completion(&event);
3055         kfree(thread);
3056 }
3057
3058 void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
3059 {
3060         if (!mddev) {
3061                 MD_BUG();
3062                 return;
3063         }
3064
3065         if (!rdev || rdev->faulty)
3066                 return;
3067 /*
3068         dprintk("md_error dev:%s, rdev:(%d:%d), (caller: %p,%p,%p,%p).\n",
3069                 mdname(mddev),
3070                 MAJOR(rdev->bdev->bd_dev), MINOR(rdev->bdev->bd_dev),
3071                 __builtin_return_address(0),__builtin_return_address(1),
3072                 __builtin_return_address(2),__builtin_return_address(3));
3073 */
3074         if (!mddev->pers->error_handler)
3075                 return;
3076         mddev->pers->error_handler(mddev,rdev);
3077         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3078         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3079         md_wakeup_thread(mddev->thread);
3080 }
3081
3082 /* seq_file implementation /proc/mdstat */
3083
3084 static void status_unused(struct seq_file *seq)
3085 {
3086         int i = 0;
3087         mdk_rdev_t *rdev;
3088         struct list_head *tmp;
3089
3090         seq_printf(seq, "unused devices: ");
3091
3092         ITERATE_RDEV_PENDING(rdev,tmp) {
3093                 char b[BDEVNAME_SIZE];
3094                 i++;
3095                 seq_printf(seq, "%s ",
3096                               bdevname(rdev->bdev,b));
3097         }
3098         if (!i)
3099                 seq_printf(seq, "<none>");
3100
3101         seq_printf(seq, "\n");
3102 }
3103
3104
3105 static void status_resync(struct seq_file *seq, mddev_t * mddev)
3106 {
3107         unsigned long max_blocks, resync, res, dt, db, rt;
3108
3109         resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active))/2;
3110
3111         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
3112                 max_blocks = mddev->resync_max_sectors >> 1;
3113         else
3114                 max_blocks = mddev->size;
3115
3116         /*
3117          * Should not happen.
3118          */
3119         if (!max_blocks) {
3120                 MD_BUG();
3121                 return;
3122         }
3123         res = (resync/1024)*1000/(max_blocks/1024 + 1);
3124         {
3125                 int i, x = res/50, y = 20-x;
3126                 seq_printf(seq, "[");
3127                 for (i = 0; i < x; i++)
3128                         seq_printf(seq, "=");
3129                 seq_printf(seq, ">");
3130                 for (i = 0; i < y; i++)
3131                         seq_printf(seq, ".");
3132                 seq_printf(seq, "] ");
3133         }
3134         seq_printf(seq, " %s =%3lu.%lu%% (%lu/%lu)",
3135                       (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
3136                        "resync" : "recovery"),
3137                       res/10, res % 10, resync, max_blocks);
3138
3139         /*
3140          * We do not want to overflow, so the order of operands and
3141          * the * 100 / 100 trick are important. We do a +1 to be
3142          * safe against division by zero. We only estimate anyway.
3143          *
3144          * dt: time from mark until now
3145          * db: blocks written from mark until now
3146          * rt: remaining time
3147          */
3148         dt = ((jiffies - mddev->resync_mark) / HZ);
3149         if (!dt) dt++;
3150         db = resync - (mddev->resync_mark_cnt/2);
3151         rt = (dt * ((max_blocks-resync) / (db/100+1)))/100;
3152
3153         seq_printf(seq, " finish=%lu.%lumin", rt / 60, (rt % 60)/6);
3154
3155         seq_printf(seq, " speed=%ldK/sec", db/dt);
3156 }
3157
3158 static void *md_seq_start(struct seq_file *seq, loff_t *pos)
3159 {
3160         struct list_head *tmp;
3161         loff_t l = *pos;
3162         mddev_t *mddev;
3163
3164         if (l >= 0x10000)
3165                 return NULL;
3166         if (!l--)
3167                 /* header */
3168                 return (void*)1;
3169
3170         spin_lock(&all_mddevs_lock);
3171         list_for_each(tmp,&all_mddevs)
3172                 if (!l--) {
3173                         mddev = list_entry(tmp, mddev_t, all_mddevs);
3174                         mddev_get(mddev);
3175                         spin_unlock(&all_mddevs_lock);
3176                         return mddev;
3177                 }
3178         spin_unlock(&all_mddevs_lock);
3179         if (!l--)
3180                 return (void*)2;/* tail */
3181         return NULL;
3182 }
3183
3184 static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3185 {
3186         struct list_head *tmp;
3187         mddev_t *next_mddev, *mddev = v;
3188
3189         ++*pos;
3190         if (v == (void*)2)
3191                 return NULL;
3192
3193         spin_lock(&all_mddevs_lock);
3194         if (v == (void*)1)
3195                 tmp = all_mddevs.next;
3196         else
3197                 tmp = mddev->all_mddevs.next;
3198         if (tmp != &all_mddevs)
3199                 next_mddev = mddev_get(list_entry(tmp,mddev_t,all_mddevs));
3200         else {
3201                 next_mddev = (void*)2;
3202                 *pos = 0x10000;
3203         }
3204         spin_unlock(&all_mddevs_lock);
3205
3206         if (v != (void*)1)
3207                 mddev_put(mddev);
3208         return next_mddev;
3209
3210 }
3211
3212 static void md_seq_stop(struct seq_file *seq, void *v)
3213 {
3214         mddev_t *mddev = v;
3215
3216         if (mddev && v != (void*)1 && v != (void*)2)
3217                 mddev_put(mddev);
3218 }
3219
3220 static int md_seq_show(struct seq_file *seq, void *v)
3221 {
3222         mddev_t *mddev = v;
3223         sector_t size;
3224         struct list_head *tmp2;
3225         mdk_rdev_t *rdev;
3226         int i;
3227         struct bitmap *bitmap;
3228
3229         if (v == (void*)1) {
3230                 seq_printf(seq, "Personalities : ");
3231                 spin_lock(&pers_lock);
3232                 for (i = 0; i < MAX_PERSONALITY; i++)
3233                         if (pers[i])
3234                                 seq_printf(seq, "[%s] ", pers[i]->name);
3235
3236                 spin_unlock(&pers_lock);
3237                 seq_printf(seq, "\n");
3238                 return 0;
3239         }
3240         if (v == (void*)2) {
3241                 status_unused(seq);
3242                 return 0;
3243         }
3244
3245         if (mddev_lock(mddev)!=0)
3246                 return -EINTR;
3247         if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
3248                 seq_printf(seq, "%s : %sactive", mdname(mddev),
3249                                                 mddev->pers ? "" : "in");
3250                 if (mddev->pers) {
3251                         if (mddev->ro)
3252                                 seq_printf(seq, " (read-only)");
3253                         seq_printf(seq, " %s", mddev->pers->name);
3254                 }
3255
3256                 size = 0;
3257                 ITERATE_RDEV(mddev,rdev,tmp2) {
3258                         char b[BDEVNAME_SIZE];
3259                         seq_printf(seq, " %s[%d]",
3260                                 bdevname(rdev->bdev,b), rdev->desc_nr);
3261                         if (rdev->faulty) {
3262                                 seq_printf(seq, "(F)");
3263                                 continue;
3264                         }
3265                         size += rdev->size;
3266                 }
3267
3268                 if (!list_empty(&mddev->disks)) {
3269                         if (mddev->pers)
3270                                 seq_printf(seq, "\n      %llu blocks",
3271                                         (unsigned long long)mddev->array_size);
3272                         else
3273                                 seq_printf(seq, "\n      %llu blocks",
3274                                         (unsigned long long)size);
3275                 }
3276
3277                 if (mddev->pers) {
3278                         mddev->pers->status (seq, mddev);
3279                         seq_printf(seq, "\n      ");
3280                         if (mddev->curr_resync > 2) {
3281                                 status_resync (seq, mddev);
3282                                 seq_printf(seq, "\n      ");
3283                         } else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
3284                                 seq_printf(seq, "       resync=DELAYED\n      ");
3285                 } else
3286                         seq_printf(seq, "\n       ");
3287
3288                 if ((bitmap = mddev->bitmap)) {
3289                         unsigned long chunk_kb;
3290                         unsigned long flags;
3291                         spin_lock_irqsave(&bitmap->lock, flags);
3292                         chunk_kb = bitmap->chunksize >> 10;
3293                         seq_printf(seq, "bitmap: %lu/%lu pages [%luKB], "
3294                                 "%lu%s chunk",
3295                                 bitmap->pages - bitmap->missing_pages,
3296                                 bitmap->pages,
3297                                 (bitmap->pages - bitmap->missing_pages)
3298                                         << (PAGE_SHIFT - 10),
3299                                 chunk_kb ? chunk_kb : bitmap->chunksize,
3300                                 chunk_kb ? "KB" : "B");
3301                         if (bitmap->file) {
3302                                 seq_printf(seq, ", file: ");
3303                                 seq_path(seq, bitmap->file->f_vfsmnt,
3304                                          bitmap->file->f_dentry," \t\n");
3305                         }
3306
3307                         seq_printf(seq, "\n");
3308                         spin_unlock_irqrestore(&bitmap->lock, flags);
3309                 }
3310
3311                 seq_printf(seq, "\n");
3312         }
3313         mddev_unlock(mddev);
3314
3315         return 0;
3316 }
3317
3318 static struct seq_operations md_seq_ops = {
3319         .start  = md_seq_start,
3320         .next   = md_seq_next,
3321         .stop   = md_seq_stop,
3322         .show   = md_seq_show,
3323 };
3324
3325 static int md_seq_open(struct inode *inode, struct file *file)
3326 {
3327         int error;
3328
3329         error = seq_open(file, &md_seq_ops);
3330         return error;
3331 }
3332
3333 static struct file_operations md_seq_fops = {
3334         .open           = md_seq_open,
3335         .read           = seq_read,
3336         .llseek         = seq_lseek,
3337         .release        = seq_release,
3338 };
3339
3340 int register_md_personality(int pnum, mdk_personality_t *p)
3341 {
3342         if (pnum >= MAX_PERSONALITY) {
3343                 printk(KERN_ERR
3344                        "md: tried to install personality %s as nr %d, but max is %lu\n",
3345                        p->name, pnum, MAX_PERSONALITY-1);
3346                 return -EINVAL;
3347         }
3348
3349         spin_lock(&pers_lock);
3350         if (pers[pnum]) {
3351                 spin_unlock(&pers_lock);
3352                 return -EBUSY;
3353         }
3354
3355         pers[pnum] = p;
3356         printk(KERN_INFO "md: %s personality registered as nr %d\n", p->name, pnum);
3357         spin_unlock(&pers_lock);
3358         return 0;
3359 }
3360
3361 int unregister_md_personality(int pnum)
3362 {
3363         if (pnum >= MAX_PERSONALITY)
3364                 return -EINVAL;
3365
3366         printk(KERN_INFO "md: %s personality unregistered\n", pers[pnum]->name);
3367         spin_lock(&pers_lock);
3368         pers[pnum] = NULL;
3369         spin_unlock(&pers_lock);
3370         return 0;
3371 }
3372
3373 static int is_mddev_idle(mddev_t *mddev)
3374 {
3375         mdk_rdev_t * rdev;
3376         struct list_head *tmp;
3377         int idle;
3378         unsigned long curr_events;
3379
3380         idle = 1;
3381         ITERATE_RDEV(mddev,rdev,tmp) {
3382                 struct gendisk *disk = rdev->bdev->bd_contains->bd_disk;
3383                 curr_events = disk_stat_read(disk, read_sectors) +
3384                                 disk_stat_read(disk, write_sectors) -
3385                                 atomic_read(&disk->sync_io);
3386                 /* Allow some slack between valud of curr_events and last_events,
3387                  * as there are some uninteresting races.
3388                  * Note: the following is an unsigned comparison.
3389                  */
3390                 if ((curr_events - rdev->last_events + 32) > 64) {
3391                         rdev->last_events = curr_events;
3392                         idle = 0;
3393                 }
3394         }
3395         return idle;
3396 }
3397
3398 void md_done_sync(mddev_t *mddev, int blocks, int ok)
3399 {
3400         /* another "blocks" (512byte) blocks have been synced */
3401         atomic_sub(blocks, &mddev->recovery_active);
3402         wake_up(&mddev->recovery_wait);
3403         if (!ok) {
3404                 set_bit(MD_RECOVERY_ERR, &mddev->recovery);
3405                 md_wakeup_thread(mddev->thread);
3406                 // stop recovery, signal do_sync ....
3407         }
3408 }
3409
3410
3411 /* md_write_start(mddev, bi)
3412  * If we need to update some array metadata (e.g. 'active' flag
3413  * in superblock) before writing, schedule a superblock update
3414  * and wait for it to complete.
3415  */
3416 void md_write_start(mddev_t *mddev, struct bio *bi)
3417 {
3418         DEFINE_WAIT(w);
3419         if (bio_data_dir(bi) != WRITE)
3420                 return;
3421
3422         atomic_inc(&mddev->writes_pending);
3423         if (mddev->in_sync) {
3424                 spin_lock(&mddev->write_lock);
3425                 if (mddev->in_sync) {
3426                         mddev->in_sync = 0;
3427                         mddev->sb_dirty = 1;
3428                         md_wakeup_thread(mddev->thread);
3429                 }
3430                 spin_unlock(&mddev->write_lock);
3431         }
3432         wait_event(mddev->sb_wait, mddev->sb_dirty==0);
3433 }
3434
3435 void md_write_end(mddev_t *mddev)
3436 {
3437         if (atomic_dec_and_test(&mddev->writes_pending)) {
3438                 if (mddev->safemode == 2)
3439                         md_wakeup_thread(mddev->thread);
3440                 else
3441                         mod_timer(&mddev->safemode_timer, jiffies + mddev->safemode_delay);
3442         }
3443 }
3444
3445 static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
3446
3447 #define SYNC_MARKS      10
3448 #define SYNC_MARK_STEP  (3*HZ)
3449 static void md_do_sync(mddev_t *mddev)
3450 {
3451         mddev_t *mddev2;
3452         unsigned int currspeed = 0,
3453                  window;
3454         sector_t max_sectors,j, io_sectors;
3455         unsigned long mark[SYNC_MARKS];
3456         sector_t mark_cnt[SYNC_MARKS];
3457         int last_mark,m;
3458         struct list_head *tmp;
3459         sector_t last_check;
3460         int skipped = 0;
3461
3462         /* just incase thread restarts... */
3463         if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
3464                 return;
3465
3466         /* we overload curr_resync somewhat here.
3467          * 0 == not engaged in resync at all
3468          * 2 == checking that there is no conflict with another sync
3469          * 1 == like 2, but have yielded to allow conflicting resync to
3470          *              commense
3471          * other == active in resync - this many blocks
3472          *
3473          * Before starting a resync we must have set curr_resync to
3474          * 2, and then checked that every "conflicting" array has curr_resync
3475          * less than ours.  When we find one that is the same or higher
3476          * we wait on resync_wait.  To avoid deadlock, we reduce curr_resync
3477          * to 1 if we choose to yield (based arbitrarily on address of mddev structure).
3478          * This will mean we have to start checking from the beginning again.
3479          *
3480          */
3481
3482         do {
3483                 mddev->curr_resync = 2;
3484
3485         try_again:
3486                 if (signal_pending(current)) {
3487                         flush_signals(current);
3488                         goto skip;
3489                 }
3490                 ITERATE_MDDEV(mddev2,tmp) {
3491                         if (mddev2 == mddev)
3492                                 continue;
3493                         if (mddev2->curr_resync &&
3494                             match_mddev_units(mddev,mddev2)) {
3495                                 DEFINE_WAIT(wq);
3496                                 if (mddev < mddev2 && mddev->curr_resync == 2) {
3497                                         /* arbitrarily yield */
3498                                         mddev->curr_resync = 1;
3499                                         wake_up(&resync_wait);
3500                                 }
3501                                 if (mddev > mddev2 && mddev->curr_resync == 1)
3502                                         /* no need to wait here, we can wait the next
3503                                          * time 'round when curr_resync == 2
3504                                          */
3505                                         continue;
3506                                 prepare_to_wait(&resync_wait, &wq, TASK_INTERRUPTIBLE);
3507                                 if (!signal_pending(current)
3508                                     && mddev2->curr_resync >= mddev->curr_resync) {
3509                                         printk(KERN_INFO "md: delaying resync of %s"
3510                                                " until %s has finished resync (they"
3511                                                " share one or more physical units)\n",
3512                                                mdname(mddev), mdname(mddev2));
3513                                         mddev_put(mddev2);
3514                                         schedule();
3515                                         finish_wait(&resync_wait, &wq);
3516                                         goto try_again;
3517                                 }
3518                                 finish_wait(&resync_wait, &wq);
3519                         }
3520                 }
3521         } while (mddev->curr_resync < 2);
3522
3523         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
3524                 /* resync follows the size requested by the personality,
3525                  * which defaults to physical size, but can be virtual size
3526                  */
3527                 max_sectors = mddev->resync_max_sectors;
3528         else
3529                 /* recovery follows the physical size of devices */
3530                 max_sectors = mddev->size << 1;
3531
3532         printk(KERN_INFO "md: syncing RAID array %s\n", mdname(mddev));
3533         printk(KERN_INFO "md: minimum _guaranteed_ reconstruction speed:"
3534                 " %d KB/sec/disc.\n", sysctl_speed_limit_min);
3535         printk(KERN_INFO "md: using maximum available idle IO bandwith "
3536                "(but not more than %d KB/sec) for reconstruction.\n",
3537                sysctl_speed_limit_max);
3538
3539         is_mddev_idle(mddev); /* this also initializes IO event counters */
3540         /* we don't use the checkpoint if there's a bitmap */
3541         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && !mddev->bitmap)
3542                 j = mddev->recovery_cp;
3543         else
3544                 j = 0;
3545         io_sectors = 0;
3546         for (m = 0; m < SYNC_MARKS; m++) {
3547                 mark[m] = jiffies;
3548                 mark_cnt[m] = io_sectors;
3549         }
3550         last_mark = 0;
3551         mddev->resync_mark = mark[last_mark];
3552         mddev->resync_mark_cnt = mark_cnt[last_mark];
3553
3554         /*
3555          * Tune reconstruction:
3556          */
3557         window = 32*(PAGE_SIZE/512);
3558         printk(KERN_INFO "md: using %dk window, over a total of %llu blocks.\n",
3559                 window/2,(unsigned long long) max_sectors/2);
3560
3561         atomic_set(&mddev->recovery_active, 0);
3562         init_waitqueue_head(&mddev->recovery_wait);
3563         last_check = 0;
3564
3565         if (j>2) {
3566                 printk(KERN_INFO
3567                         "md: resuming recovery of %s from checkpoint.\n",
3568                         mdname(mddev));
3569                 mddev->curr_resync = j;
3570         }
3571
3572         while (j < max_sectors) {
3573                 sector_t sectors;
3574
3575                 skipped = 0;
3576                 sectors = mddev->pers->sync_request(mddev, j, &skipped,
3577                                             currspeed < sysctl_speed_limit_min);
3578                 if (sectors == 0) {
3579                         set_bit(MD_RECOVERY_ERR, &mddev->recovery);
3580                         goto out;
3581                 }
3582
3583                 if (!skipped) { /* actual IO requested */
3584                         io_sectors += sectors;
3585                         atomic_add(sectors, &mddev->recovery_active);
3586                 }
3587
3588                 j += sectors;
3589                 if (j>1) mddev->curr_resync = j;
3590
3591
3592                 if (last_check + window > io_sectors || j == max_sectors)
3593                         continue;
3594
3595                 last_check = io_sectors;
3596
3597                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery) ||
3598                     test_bit(MD_RECOVERY_ERR, &mddev->recovery))
3599                         break;
3600
3601         repeat:
3602                 if (time_after_eq(jiffies, mark[last_mark] + SYNC_MARK_STEP )) {
3603                         /* step marks */
3604                         int next = (last_mark+1) % SYNC_MARKS;
3605
3606                         mddev->resync_mark = mark[next];
3607                         mddev->resync_mark_cnt = mark_cnt[next];
3608                         mark[next] = jiffies;
3609                         mark_cnt[next] = io_sectors - atomic_read(&mddev->recovery_active);
3610                         last_mark = next;
3611                 }
3612
3613
3614                 if (signal_pending(current)) {
3615                         /*
3616                          * got a signal, exit.
3617                          */
3618                         printk(KERN_INFO
3619                                 "md: md_do_sync() got signal ... exiting\n");
3620                         flush_signals(current);
3621                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3622                         goto out;
3623                 }
3624
3625                 /*
3626                  * this loop exits only if either when we are slower than
3627                  * the 'hard' speed limit, or the system was IO-idle for
3628                  * a jiffy.
3629                  * the system might be non-idle CPU-wise, but we only care
3630                  * about not overloading the IO subsystem. (things like an
3631                  * e2fsck being done on the RAID array should execute fast)
3632                  */
3633                 mddev->queue->unplug_fn(mddev->queue);
3634                 cond_resched();
3635
3636                 currspeed = ((unsigned long)(io_sectors-mddev->resync_mark_cnt))/2
3637                         /((jiffies-mddev->resync_mark)/HZ +1) +1;
3638
3639                 if (currspeed > sysctl_speed_limit_min) {
3640                         if ((currspeed > sysctl_speed_limit_max) ||
3641                                         !is_mddev_idle(mddev)) {
3642                                 msleep_interruptible(250);
3643                                 goto repeat;
3644                         }
3645                 }
3646         }
3647         printk(KERN_INFO "md: %s: sync done.\n",mdname(mddev));
3648         /*
3649          * this also signals 'finished resyncing' to md_stop
3650          */
3651  out:
3652         mddev->queue->unplug_fn(mddev->queue);
3653
3654         wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
3655
3656         /* tell personality that we are finished */
3657         mddev->pers->sync_request(mddev, max_sectors, &skipped, 1);
3658
3659         if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
3660             mddev->curr_resync > 2 &&
3661             mddev->curr_resync >= mddev->recovery_cp) {
3662                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
3663                         printk(KERN_INFO
3664                                 "md: checkpointing recovery of %s.\n",
3665                                 mdname(mddev));
3666                         mddev->recovery_cp = mddev->curr_resync;
3667                 } else
3668                         mddev->recovery_cp = MaxSector;
3669         }
3670
3671  skip:
3672         mddev->curr_resync = 0;
3673         wake_up(&resync_wait);
3674         set_bit(MD_RECOVERY_DONE, &mddev->recovery);
3675         md_wakeup_thread(mddev->thread);
3676 }
3677
3678
3679 /*
3680  * This routine is regularly called by all per-raid-array threads to
3681  * deal with generic issues like resync and super-block update.
3682  * Raid personalities that don't have a thread (linear/raid0) do not
3683  * need this as they never do any recovery or update the superblock.
3684  *
3685  * It does not do any resync itself, but rather "forks" off other threads
3686  * to do that as needed.
3687  * When it is determined that resync is needed, we set MD_RECOVERY_RUNNING in
3688  * "->recovery" and create a thread at ->sync_thread.
3689  * When the thread finishes it sets MD_RECOVERY_DONE (and might set MD_RECOVERY_ERR)
3690  * and wakeups up this thread which will reap the thread and finish up.
3691  * This thread also removes any faulty devices (with nr_pending == 0).
3692  *
3693  * The overall approach is:
3694  *  1/ if the superblock needs updating, update it.
3695  *  2/ If a recovery thread is running, don't do anything else.
3696  *  3/ If recovery has finished, clean up, possibly marking spares active.
3697  *  4/ If there are any faulty devices, remove them.
3698  *  5/ If array is degraded, try to add spares devices
3699  *  6/ If array has spares or is not in-sync, start a resync thread.
3700  */
3701 void md_check_recovery(mddev_t *mddev)
3702 {
3703         mdk_rdev_t *rdev;
3704         struct list_head *rtmp;
3705
3706
3707         if (mddev->bitmap)
3708                 bitmap_daemon_work(mddev->bitmap);
3709
3710         if (mddev->ro)
3711                 return;
3712
3713         if (signal_pending(current)) {
3714                 if (mddev->pers->sync_request) {
3715                         printk(KERN_INFO "md: %s in immediate safe mode\n",
3716                                mdname(mddev));
3717                         mddev->safemode = 2;
3718                 }
3719                 flush_signals(current);
3720         }
3721
3722         if ( ! (
3723                 mddev->sb_dirty ||
3724                 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
3725                 test_bit(MD_RECOVERY_DONE, &mddev->recovery) ||
3726                 (mddev->safemode == 1) ||
3727                 (mddev->safemode == 2 && ! atomic_read(&mddev->writes_pending)
3728                  && !mddev->in_sync && mddev->recovery_cp == MaxSector)
3729                 ))
3730                 return;
3731
3732         if (mddev_trylock(mddev)==0) {
3733                 int spares =0;
3734
3735                 spin_lock(&mddev->write_lock);
3736                 if (mddev->safemode && !atomic_read(&mddev->writes_pending) &&
3737                     !mddev->in_sync && mddev->recovery_cp == MaxSector) {
3738                         mddev->in_sync = 1;
3739                         mddev->sb_dirty = 1;
3740                 }
3741                 if (mddev->safemode == 1)
3742                         mddev->safemode = 0;
3743                 spin_unlock(&mddev->write_lock);
3744
3745                 if (mddev->sb_dirty)
3746                         md_update_sb(mddev);
3747
3748
3749                 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
3750                     !test_bit(MD_RECOVERY_DONE, &mddev->recovery)) {
3751                         /* resync/recovery still happening */
3752                         clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3753                         goto unlock;
3754                 }
3755                 if (mddev->sync_thread) {
3756                         /* resync has finished, collect result */
3757                         md_unregister_thread(mddev->sync_thread);
3758                         mddev->sync_thread = NULL;
3759                         if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
3760                             !test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
3761                                 /* success...*/
3762                                 /* activate any spares */
3763                                 mddev->pers->spare_active(mddev);
3764                         }
3765                         md_update_sb(mddev);
3766
3767                         /* if array is no-longer degraded, then any saved_raid_disk
3768                          * information must be scrapped
3769                          */
3770                         if (!mddev->degraded)
3771                                 ITERATE_RDEV(mddev,rdev,rtmp)
3772                                         rdev->saved_raid_disk = -1;
3773
3774                         mddev->recovery = 0;
3775                         /* flag recovery needed just to double check */
3776                         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3777                         goto unlock;
3778                 }
3779                 if (mddev->recovery)
3780                         /* probably just the RECOVERY_NEEDED flag */
3781                         mddev->recovery = 0;
3782
3783                 /* no recovery is running.
3784                  * remove any failed drives, then
3785                  * add spares if possible.
3786                  * Spare are also removed and re-added, to allow
3787                  * the personality to fail the re-add.
3788                  */
3789                 ITERATE_RDEV(mddev,rdev,rtmp)
3790                         if (rdev->raid_disk >= 0 &&
3791                             (rdev->faulty || ! rdev->in_sync) &&
3792                             atomic_read(&rdev->nr_pending)==0) {
3793                                 if (mddev->pers->hot_remove_disk(mddev, rdev->raid_disk)==0)
3794                                         rdev->raid_disk = -1;
3795                         }
3796
3797                 if (mddev->degraded) {
3798                         ITERATE_RDEV(mddev,rdev,rtmp)
3799                                 if (rdev->raid_disk < 0
3800                                     && !rdev->faulty) {
3801                                         if (mddev->pers->hot_add_disk(mddev,rdev))
3802                                                 spares++;
3803                                         else
3804                                                 break;
3805                                 }
3806                 }
3807
3808                 if (!spares && (mddev->recovery_cp == MaxSector )) {
3809                         /* nothing we can do ... */
3810                         goto unlock;
3811                 }
3812                 if (mddev->pers->sync_request) {
3813                         set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
3814                         if (!spares)
3815                                 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3816                         if (spares && mddev->bitmap && ! mddev->bitmap->file) {
3817                                 /* We are adding a device or devices to an array
3818                                  * which has the bitmap stored on all devices.
3819                                  * So make sure all bitmap pages get written
3820                                  */
3821                                 bitmap_write_all(mddev->bitmap);
3822                         }
3823                         mddev->sync_thread = md_register_thread(md_do_sync,
3824                                                                 mddev,
3825                                                                 "%s_resync");
3826                         if (!mddev->sync_thread) {
3827                                 printk(KERN_ERR "%s: could not start resync"
3828                                         " thread...\n",
3829                                         mdname(mddev));
3830                                 /* leave the spares where they are, it shouldn't hurt */
3831                                 mddev->recovery = 0;
3832                         } else {
3833                                 md_wakeup_thread(mddev->sync_thread);
3834                         }
3835                 }
3836         unlock:
3837                 mddev_unlock(mddev);
3838         }
3839 }
3840
3841 static int md_notify_reboot(struct notifier_block *this,
3842                             unsigned long code, void *x)
3843 {
3844         struct list_head *tmp;
3845         mddev_t *mddev;
3846
3847         if ((code == SYS_DOWN) || (code == SYS_HALT) || (code == SYS_POWER_OFF)) {
3848
3849                 printk(KERN_INFO "md: stopping all md devices.\n");
3850
3851                 ITERATE_MDDEV(mddev,tmp)
3852                         if (mddev_trylock(mddev)==0)
3853                                 do_md_stop (mddev, 1);
3854                 /*
3855                  * certain more exotic SCSI devices are known to be
3856                  * volatile wrt too early system reboots. While the
3857                  * right place to handle this issue is the given
3858                  * driver, we do want to have a safe RAID driver ...
3859                  */
3860                 mdelay(1000*1);
3861         }
3862         return NOTIFY_DONE;
3863 }
3864
3865 static struct notifier_block md_notifier = {
3866         .notifier_call  = md_notify_reboot,
3867         .next           = NULL,
3868         .priority       = INT_MAX, /* before any real devices */
3869 };
3870
3871 static void md_geninit(void)
3872 {
3873         struct proc_dir_entry *p;
3874
3875         dprintk("md: sizeof(mdp_super_t) = %d\n", (int)sizeof(mdp_super_t));
3876
3877         p = create_proc_entry("mdstat", S_IRUGO, NULL);
3878         if (p)
3879                 p->proc_fops = &md_seq_fops;
3880 }
3881
3882 static int __init md_init(void)
3883 {
3884         int minor;
3885
3886         printk(KERN_INFO "md: md driver %d.%d.%d MAX_MD_DEVS=%d,"
3887                         " MD_SB_DISKS=%d\n",
3888                         MD_MAJOR_VERSION, MD_MINOR_VERSION,
3889                         MD_PATCHLEVEL_VERSION, MAX_MD_DEVS, MD_SB_DISKS);
3890         printk(KERN_INFO "md: bitmap version %d.%d\n", BITMAP_MAJOR,
3891                         BITMAP_MINOR);
3892
3893         if (register_blkdev(MAJOR_NR, "md"))
3894                 return -1;
3895         if ((mdp_major=register_blkdev(0, "mdp"))<=0) {
3896                 unregister_blkdev(MAJOR_NR, "md");
3897                 return -1;
3898         }
3899         devfs_mk_dir("md");
3900         blk_register_region(MKDEV(MAJOR_NR, 0), MAX_MD_DEVS, THIS_MODULE,
3901                                 md_probe, NULL, NULL);
3902         blk_register_region(MKDEV(mdp_major, 0), MAX_MD_DEVS<<MdpMinorShift, THIS_MODULE,
3903                             md_probe, NULL, NULL);
3904
3905         for (minor=0; minor < MAX_MD_DEVS; ++minor)
3906                 devfs_mk_bdev(MKDEV(MAJOR_NR, minor),
3907                                 S_IFBLK|S_IRUSR|S_IWUSR,
3908                                 "md/%d", minor);
3909
3910         for (minor=0; minor < MAX_MD_DEVS; ++minor)
3911                 devfs_mk_bdev(MKDEV(mdp_major, minor<<MdpMinorShift),
3912                               S_IFBLK|S_IRUSR|S_IWUSR,
3913                               "md/mdp%d", minor);
3914
3915
3916         register_reboot_notifier(&md_notifier);
3917         raid_table_header = register_sysctl_table(raid_root_table, 1);
3918
3919         md_geninit();
3920         return (0);
3921 }
3922
3923
3924 #ifndef MODULE
3925
3926 /*
3927  * Searches all registered partitions for autorun RAID arrays
3928  * at boot time.
3929  */
3930 static dev_t detected_devices[128];
3931 static int dev_cnt;
3932
3933 void md_autodetect_dev(dev_t dev)
3934 {
3935         if (dev_cnt >= 0 && dev_cnt < 127)
3936                 detected_devices[dev_cnt++] = dev;
3937 }
3938
3939
3940 static void autostart_arrays(int part)
3941 {
3942         mdk_rdev_t *rdev;
3943         int i;
3944
3945         printk(KERN_INFO "md: Autodetecting RAID arrays.\n");
3946
3947         for (i = 0; i < dev_cnt; i++) {
3948                 dev_t dev = detected_devices[i];
3949
3950                 rdev = md_import_device(dev,0, 0);
3951                 if (IS_ERR(rdev))
3952                         continue;
3953
3954                 if (rdev->faulty) {
3955                         MD_BUG();
3956                         continue;
3957                 }
3958                 list_add(&rdev->same_set, &pending_raid_disks);
3959         }
3960         dev_cnt = 0;
3961
3962         autorun_devices(part);
3963 }
3964
3965 #endif
3966
3967 static __exit void md_exit(void)
3968 {
3969         mddev_t *mddev;
3970         struct list_head *tmp;
3971         int i;
3972         blk_unregister_region(MKDEV(MAJOR_NR,0), MAX_MD_DEVS);
3973         blk_unregister_region(MKDEV(mdp_major,0), MAX_MD_DEVS << MdpMinorShift);
3974         for (i=0; i < MAX_MD_DEVS; i++)
3975                 devfs_remove("md/%d", i);
3976         for (i=0; i < MAX_MD_DEVS; i++)
3977                 devfs_remove("md/d%d", i);
3978
3979         devfs_remove("md");
3980
3981         unregister_blkdev(MAJOR_NR,"md");
3982         unregister_blkdev(mdp_major, "mdp");
3983         unregister_reboot_notifier(&md_notifier);
3984         unregister_sysctl_table(raid_table_header);
3985         remove_proc_entry("mdstat", NULL);
3986         ITERATE_MDDEV(mddev,tmp) {
3987                 struct gendisk *disk = mddev->gendisk;
3988                 if (!disk)
3989                         continue;
3990                 export_array(mddev);
3991                 del_gendisk(disk);
3992                 put_disk(disk);
3993                 mddev->gendisk = NULL;
3994                 mddev_put(mddev);
3995         }
3996 }
3997
3998 module_init(md_init)
3999 module_exit(md_exit)
4000
4001 EXPORT_SYMBOL(register_md_personality);
4002 EXPORT_SYMBOL(unregister_md_personality);
4003 EXPORT_SYMBOL(md_error);
4004 EXPORT_SYMBOL(md_done_sync);
4005 EXPORT_SYMBOL(md_write_start);
4006 EXPORT_SYMBOL(md_write_end);
4007 EXPORT_SYMBOL(md_register_thread);
4008 EXPORT_SYMBOL(md_unregister_thread);
4009 EXPORT_SYMBOL(md_wakeup_thread);
4010 EXPORT_SYMBOL(md_print_devices);
4011 EXPORT_SYMBOL(md_check_recovery);
4012 MODULE_LICENSE("GPL");
4013 MODULE_ALIAS("md");