SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/md/md.c

   1 /*
   2    md.c : Multiple Devices driver for Linux
   3           Copyright (C) 1998, 1999, 2000 Ingo Molnar
   4
   5      completely rewritten, based on the MD driver code from Marc Zyngier
   6
   7    Changes:
   8
   9    - RAID-1/RAID-5 extensions by Miguel de Icaza, Gadi Oxman, Ingo Molnar
  10    - RAID-6 extensions by H. Peter Anvin <hpa@zytor.com>
  11    - boot support for linear and striped mode by Harald Hoyer <HarryH@Royal.Net>
  12    - kerneld support by Boris Tobotras <boris@xtalk.msk.su>
  13    - kmod support by: Cyrus Durgin
  14    - RAID0 bugfixes: Mark Anthony Lisher <markal@iname.com>
  15    - Devfs support by Richard Gooch <rgooch@atnf.csiro.au>
  16
  17    - lots of fixes and improvements to the RAID1/RAID5 and generic
  18      RAID code (such as request based resynchronization):
  19
  20      Neil Brown <neilb@cse.unsw.edu.au>.
  21
  22    This program is free software; you can redistribute it and/or modify
  23    it under the terms of the GNU General Public License as published by
  24    the Free Software Foundation; either version 2, or (at your option)
  25    any later version.
  26
  27    You should have received a copy of the GNU General Public License
  28    (for example /usr/src/linux/COPYING); if not, write to the Free
  29    Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  30 */
  31
  32 #include <linux/module.h>
  33 #include <linux/config.h>
  34 #include <linux/linkage.h>
  35 #include <linux/raid/md.h>
  36 #include <linux/sysctl.h>
  37 #include <linux/devfs_fs_kernel.h>
  38 #include <linux/buffer_head.h> /* for invalidate_bdev */
  39 #include <linux/suspend.h>
  40
  41 #include <linux/init.h>
  42
  43 #ifdef CONFIG_KMOD
  44 #include <linux/kmod.h>
  45 #endif
  46
  47 #include <asm/unaligned.h>
  48
  49 #define MAJOR_NR MD_MAJOR
  50 #define MD_DRIVER
  51
  52 /* 63 partitions with the alternate major number (mdp) */
  53 #define MdpMinorShift 6
  54
  55 #define DEBUG 0
  56 #define dprintk(x...) ((void)(DEBUG && printk(x)))
  57
  58
  59 #ifndef MODULE
  60 static void autostart_arrays (int part);
  61 #endif
  62
  63 static mdk_personality_t *pers[MAX_PERSONALITY];
  64 static DEFINE_SPINLOCK(pers_lock);
  65
  66 /*
  67  * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
  68  * is 1000 KB/sec, so the extra system load does not show up that much.
  69  * Increase it if you want to have more _guaranteed_ speed. Note that
  70  * the RAID driver will use the maximum available bandwith if the IO
  71  * subsystem is idle. There is also an 'absolute maximum' reconstruction
  72  * speed limit - in case reconstruction slows down your system despite
  73  * idle IO detection.
  74  *
  75  * you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
  76  */
  77
  78 static int sysctl_speed_limit_min = 1000;
  79 static int sysctl_speed_limit_max = 200000;
  80
  81 static struct ctl_table_header *raid_table_header;
  82
  83 static ctl_table raid_table[] = {
  84         {
  85                 .ctl_name       = DEV_RAID_SPEED_LIMIT_MIN,
  86                 .procname       = "speed_limit_min",
  87                 .data           = &sysctl_speed_limit_min,
  88                 .maxlen         = sizeof(int),
  89                 .mode           = 0644,
  90                 .proc_handler   = &proc_dointvec,
  91         },
  92         {
  93                 .ctl_name       = DEV_RAID_SPEED_LIMIT_MAX,
  94                 .procname       = "speed_limit_max",
  95                 .data           = &sysctl_speed_limit_max,
  96                 .maxlen         = sizeof(int),
  97                 .mode           = 0644,
  98                 .proc_handler   = &proc_dointvec,
  99         },
 100         { .ctl_name = 0 }
 101 };
 102
 103 static ctl_table raid_dir_table[] = {
 104         {
 105                 .ctl_name       = DEV_RAID,
 106                 .procname       = "raid",
 107                 .maxlen         = 0,
 108                 .mode           = 0555,
 109                 .child          = raid_table,
 110         },
 111         { .ctl_name = 0 }
 112 };
 113
 114 static ctl_table raid_root_table[] = {
 115         {
 116                 .ctl_name       = CTL_DEV,
 117                 .procname       = "dev",
 118                 .maxlen         = 0,
 119                 .mode           = 0555,
 120                 .child          = raid_dir_table,
 121         },
 122         { .ctl_name = 0 }
 123 };
 124
 125 static struct block_device_operations md_fops;
 126
 127 /*
 128  * Enables to iterate over all existing md arrays
 129  * all_mddevs_lock protects this list.
 130  */
 131 static LIST_HEAD(all_mddevs);
 132 static DEFINE_SPINLOCK(all_mddevs_lock);
 133
 134
 135 /*
 136  * iterates through all used mddevs in the system.
 137  * We take care to grab the all_mddevs_lock whenever navigating
 138  * the list, and to always hold a refcount when unlocked.
 139  * Any code which breaks out of this loop while own
 140  * a reference to the current mddev and must mddev_put it.
 141  */
 142 #define ITERATE_MDDEV(mddev,tmp)                                        \
 143                                                                         \
 144         for (({ spin_lock(&all_mddevs_lock);                            \
 145                 tmp = all_mddevs.next;                                  \
 146                 mddev = NULL;});                                        \
 147              ({ if (tmp != &all_mddevs)                                 \
 148                         mddev_get(list_entry(tmp, mddev_t, all_mddevs));\
 149                 spin_unlock(&all_mddevs_lock);                          \
 150                 if (mddev) mddev_put(mddev);                            \
 151                 mddev = list_entry(tmp, mddev_t, all_mddevs);           \
 152                 tmp != &all_mddevs;});                                  \
 153              ({ spin_lock(&all_mddevs_lock);                            \
 154                 tmp = tmp->next;})                                      \
 155                 )
 156
 157
 158 static int md_fail_request (request_queue_t *q, struct bio *bio)
 159 {
 160         bio_io_error(bio, bio->bi_size);
 161         return 0;
 162 }
 163
 164 static inline mddev_t *mddev_get(mddev_t *mddev)
 165 {
 166         atomic_inc(&mddev->active);
 167         return mddev;
 168 }
 169
 170 static void mddev_put(mddev_t *mddev)
 171 {
 172         if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
 173                 return;
 174         if (!mddev->raid_disks && list_empty(&mddev->disks)) {
 175                 list_del(&mddev->all_mddevs);
 176                 blk_put_queue(mddev->queue);
 177                 kfree(mddev);
 178         }
 179         spin_unlock(&all_mddevs_lock);
 180 }
 181
 182 static mddev_t * mddev_find(dev_t unit)
 183 {
 184         mddev_t *mddev, *new = NULL;
 185
 186  retry:
 187         spin_lock(&all_mddevs_lock);
 188         list_for_each_entry(mddev, &all_mddevs, all_mddevs)
 189                 if (mddev->unit == unit) {
 190                         mddev_get(mddev);
 191                         spin_unlock(&all_mddevs_lock);
 192                         if (new)
 193                                 kfree(new);
 194                         return mddev;
 195                 }
 196
 197         if (new) {
 198                 list_add(&new->all_mddevs, &all_mddevs);
 199                 spin_unlock(&all_mddevs_lock);
 200                 return new;
 201         }
 202         spin_unlock(&all_mddevs_lock);
 203
 204         new = (mddev_t *) kmalloc(sizeof(*new), GFP_KERNEL);
 205         if (!new)
 206                 return NULL;
 207
 208         memset(new, 0, sizeof(*new));
 209
 210         new->unit = unit;
 211         if (MAJOR(unit) == MD_MAJOR)
 212                 new->md_minor = MINOR(unit);
 213         else
 214                 new->md_minor = MINOR(unit) >> MdpMinorShift;
 215
 216         init_MUTEX(&new->reconfig_sem);
 217         INIT_LIST_HEAD(&new->disks);
 218         INIT_LIST_HEAD(&new->all_mddevs);
 219         init_timer(&new->safemode_timer);
 220         atomic_set(&new->active, 1);
 221
 222         new->queue = blk_alloc_queue(GFP_KERNEL);
 223         if (!new->queue) {
 224                 kfree(new);
 225                 return NULL;
 226         }
 227
 228         blk_queue_make_request(new->queue, md_fail_request);
 229
 230         goto retry;
 231 }
 232
 233 static inline int mddev_lock(mddev_t * mddev)
 234 {
 235         return down_interruptible(&mddev->reconfig_sem);
 236 }
 237
 238 static inline void mddev_lock_uninterruptible(mddev_t * mddev)
 239 {
 240         down(&mddev->reconfig_sem);
 241 }
 242
 243 static inline int mddev_trylock(mddev_t * mddev)
 244 {
 245         return down_trylock(&mddev->reconfig_sem);
 246 }
 247
 248 static inline void mddev_unlock(mddev_t * mddev)
 249 {
 250         up(&mddev->reconfig_sem);
 251
 252         if (mddev->thread)
 253                 md_wakeup_thread(mddev->thread);
 254 }
 255
 256 mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr)
 257 {
 258         mdk_rdev_t * rdev;
 259         struct list_head *tmp;
 260
 261         ITERATE_RDEV(mddev,rdev,tmp) {
 262                 if (rdev->desc_nr == nr)
 263                         return rdev;
 264         }
 265         return NULL;
 266 }
 267
 268 static mdk_rdev_t * find_rdev(mddev_t * mddev, dev_t dev)
 269 {
 270         struct list_head *tmp;
 271         mdk_rdev_t *rdev;
 272
 273         ITERATE_RDEV(mddev,rdev,tmp) {
 274                 if (rdev->bdev->bd_dev == dev)
 275                         return rdev;
 276         }
 277         return NULL;
 278 }
 279
 280 inline static sector_t calc_dev_sboffset(struct block_device *bdev)
 281 {
 282         sector_t size = bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
 283         return MD_NEW_SIZE_BLOCKS(size);
 284 }
 285
 286 static sector_t calc_dev_size(mdk_rdev_t *rdev, unsigned chunk_size)
 287 {
 288         sector_t size;
 289
 290         size = rdev->sb_offset;
 291
 292         if (chunk_size)
 293                 size &= ~((sector_t)chunk_size/1024 - 1);
 294         return size;
 295 }
 296
 297 static int alloc_disk_sb(mdk_rdev_t * rdev)
 298 {
 299         if (rdev->sb_page)
 300                 MD_BUG();
 301
 302         rdev->sb_page = alloc_page(GFP_KERNEL);
 303         if (!rdev->sb_page) {
 304                 printk(KERN_ALERT "md: out of memory.\n");
 305                 return -EINVAL;
 306         }
 307
 308         return 0;
 309 }
 310
 311 static void free_disk_sb(mdk_rdev_t * rdev)
 312 {
 313         if (rdev->sb_page) {
 314                 page_cache_release(rdev->sb_page);
 315                 rdev->sb_loaded = 0;
 316                 rdev->sb_page = NULL;
 317                 rdev->sb_offset = 0;
 318                 rdev->size = 0;
 319         }
 320 }
 321
 322
 323 static int bi_complete(struct bio *bio, unsigned int bytes_done, int error)
 324 {
 325         if (bio->bi_size)
 326                 return 1;
 327
 328         complete((struct completion*)bio->bi_private);
 329         return 0;
 330 }
 331
 332 static int sync_page_io(struct block_device *bdev, sector_t sector, int size,
 333                    struct page *page, int rw)
 334 {
 335         struct bio *bio = bio_alloc(GFP_NOIO, 1);
 336         struct completion event;
 337         int ret;
 338
 339         rw |= (1 << BIO_RW_SYNC);
 340
 341         bio->bi_bdev = bdev;
 342         bio->bi_sector = sector;
 343         bio_add_page(bio, page, size, 0);
 344         init_completion(&event);
 345         bio->bi_private = &event;
 346         bio->bi_end_io = bi_complete;
 347         submit_bio(rw, bio);
 348         wait_for_completion(&event);
 349
 350         ret = test_bit(BIO_UPTODATE, &bio->bi_flags);
 351         bio_put(bio);
 352         return ret;
 353 }
 354
 355 static int read_disk_sb(mdk_rdev_t * rdev)
 356 {
 357         char b[BDEVNAME_SIZE];
 358         if (!rdev->sb_page) {
 359                 MD_BUG();
 360                 return -EINVAL;
 361         }
 362         if (rdev->sb_loaded)
 363                 return 0;
 364
 365
 366         if (!sync_page_io(rdev->bdev, rdev->sb_offset<<1, MD_SB_BYTES, rdev->sb_page, READ))
 367                 goto fail;
 368         rdev->sb_loaded = 1;
 369         return 0;
 370
 371 fail:
 372         printk(KERN_WARNING "md: disabled device %s, could not read superblock.\n",
 373                 bdevname(rdev->bdev,b));
 374         return -EINVAL;
 375 }
 376
 377 static int uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 378 {
 379         if (    (sb1->set_uuid0 == sb2->set_uuid0) &&
 380                 (sb1->set_uuid1 == sb2->set_uuid1) &&
 381                 (sb1->set_uuid2 == sb2->set_uuid2) &&
 382                 (sb1->set_uuid3 == sb2->set_uuid3))
 383
 384                 return 1;
 385
 386         return 0;
 387 }
 388
 389
 390 static int sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 391 {
 392         int ret;
 393         mdp_super_t *tmp1, *tmp2;
 394
 395         tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
 396         tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
 397
 398         if (!tmp1 || !tmp2) {
 399                 ret = 0;
 400                 printk(KERN_INFO "md.c: sb1 is not equal to sb2!\n");
 401                 goto abort;
 402         }
 403
 404         *tmp1 = *sb1;
 405         *tmp2 = *sb2;
 406
 407         /*
 408          * nr_disks is not constant
 409          */
 410         tmp1->nr_disks = 0;
 411         tmp2->nr_disks = 0;
 412
 413         if (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4))
 414                 ret = 0;
 415         else
 416                 ret = 1;
 417
 418 abort:
 419         if (tmp1)
 420                 kfree(tmp1);
 421         if (tmp2)
 422                 kfree(tmp2);
 423
 424         return ret;
 425 }
 426
 427 static unsigned int calc_sb_csum(mdp_super_t * sb)
 428 {
 429         unsigned int disk_csum, csum;
 430
 431         disk_csum = sb->sb_csum;
 432         sb->sb_csum = 0;
 433         csum = csum_partial((void *)sb, MD_SB_BYTES, 0);
 434         sb->sb_csum = disk_csum;
 435         return csum;
 436 }
 437
 438
 439 /*
 440  * Handle superblock details.
 441  * We want to be able to handle multiple superblock formats
 442  * so we have a common interface to them all, and an array of
 443  * different handlers.
 444  * We rely on user-space to write the initial superblock, and support
 445  * reading and updating of superblocks.
 446  * Interface methods are:
 447  *   int load_super(mdk_rdev_t *dev, mdk_rdev_t *refdev, int minor_version)
 448  *      loads and validates a superblock on dev.
 449  *      if refdev != NULL, compare superblocks on both devices
 450  *    Return:
 451  *      0 - dev has a superblock that is compatible with refdev
 452  *      1 - dev has a superblock that is compatible and newer than refdev
 453  *          so dev should be used as the refdev in future
 454  *     -EINVAL superblock incompatible or invalid
 455  *     -othererror e.g. -EIO
 456  *
 457  *   int validate_super(mddev_t *mddev, mdk_rdev_t *dev)
 458  *      Verify that dev is acceptable into mddev.
 459  *       The first time, mddev->raid_disks will be 0, and data from
 460  *       dev should be merged in.  Subsequent calls check that dev
 461  *       is new enough.  Return 0 or -EINVAL
 462  *
 463  *   void sync_super(mddev_t *mddev, mdk_rdev_t *dev)
 464  *     Update the superblock for rdev with data in mddev
 465  *     This does not write to disc.
 466  *
 467  */
 468
 469 struct super_type  {
 470         char            *name;
 471         struct module   *owner;
 472         int             (*load_super)(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version);
 473         int             (*validate_super)(mddev_t *mddev, mdk_rdev_t *rdev);
 474         void            (*sync_super)(mddev_t *mddev, mdk_rdev_t *rdev);
 475 };
 476
 477 /*
 478  * load_super for 0.90.0
 479  */
 480 static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
 481 {
 482         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
 483         mdp_super_t *sb;
 484         int ret;
 485         sector_t sb_offset;
 486
 487         /*
 488          * Calculate the position of the superblock,
 489          * it's at the end of the disk.
 490          *
 491          * It also happens to be a multiple of 4Kb.
 492          */
 493         sb_offset = calc_dev_sboffset(rdev->bdev);
 494         rdev->sb_offset = sb_offset;
 495
 496         ret = read_disk_sb(rdev);
 497         if (ret) return ret;
 498
 499         ret = -EINVAL;
 500
 501         bdevname(rdev->bdev, b);
 502         sb = (mdp_super_t*)page_address(rdev->sb_page);
 503
 504         if (sb->md_magic != MD_SB_MAGIC) {
 505                 printk(KERN_ERR "md: invalid raid superblock magic on %s\n",
 506                        b);
 507                 goto abort;
 508         }
 509
 510         if (sb->major_version != 0 ||
 511             sb->minor_version != 90) {
 512                 printk(KERN_WARNING "Bad version number %d.%d on %s\n",
 513                         sb->major_version, sb->minor_version,
 514                         b);
 515                 goto abort;
 516         }
 517
 518         if (sb->raid_disks <= 0)
 519                 goto abort;
 520
 521         if (csum_fold(calc_sb_csum(sb)) != csum_fold(sb->sb_csum)) {
 522                 printk(KERN_WARNING "md: invalid superblock checksum on %s\n",
 523                         b);
 524                 goto abort;
 525         }
 526
 527         rdev->preferred_minor = sb->md_minor;
 528         rdev->data_offset = 0;
 529
 530         if (sb->level == LEVEL_MULTIPATH)
 531                 rdev->desc_nr = -1;
 532         else
 533                 rdev->desc_nr = sb->this_disk.number;
 534
 535         if (refdev == 0)
 536                 ret = 1;
 537         else {
 538                 __u64 ev1, ev2;
 539                 mdp_super_t *refsb = (mdp_super_t*)page_address(refdev->sb_page);
 540                 if (!uuid_equal(refsb, sb)) {
 541                         printk(KERN_WARNING "md: %s has different UUID to %s\n",
 542                                 b, bdevname(refdev->bdev,b2));
 543                         goto abort;
 544                 }
 545                 if (!sb_equal(refsb, sb)) {
 546                         printk(KERN_WARNING "md: %s has same UUID"
 547                                " but different superblock to %s\n",
 548                                b, bdevname(refdev->bdev, b2));
 549                         goto abort;
 550                 }
 551                 ev1 = md_event(sb);
 552                 ev2 = md_event(refsb);
 553                 if (ev1 > ev2)
 554                         ret = 1;
 555                 else
 556                         ret = 0;
 557         }
 558         rdev->size = calc_dev_size(rdev, sb->chunk_size);
 559
 560  abort:
 561         return ret;
 562 }
 563
 564 /*
 565  * validate_super for 0.90.0
 566  */
 567 static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
 568 {
 569         mdp_disk_t *desc;
 570         mdp_super_t *sb = (mdp_super_t *)page_address(rdev->sb_page);
 571
 572         if (mddev->raid_disks == 0) {
 573                 mddev->major_version = 0;
 574                 mddev->minor_version = sb->minor_version;
 575                 mddev->patch_version = sb->patch_version;
 576                 mddev->persistent = ! sb->not_persistent;
 577                 mddev->chunk_size = sb->chunk_size;
 578                 mddev->ctime = sb->ctime;
 579                 mddev->utime = sb->utime;
 580                 mddev->level = sb->level;
 581                 mddev->layout = sb->layout;
 582                 mddev->raid_disks = sb->raid_disks;
 583                 mddev->size = sb->size;
 584                 mddev->events = md_event(sb);
 585
 586                 if (sb->state & (1<<MD_SB_CLEAN))
 587                         mddev->recovery_cp = MaxSector;
 588                 else {
 589                         if (sb->events_hi == sb->cp_events_hi &&
 590                                 sb->events_lo == sb->cp_events_lo) {
 591                                 mddev->recovery_cp = sb->recovery_cp;
 592                         } else
 593                                 mddev->recovery_cp = 0;
 594                 }
 595
 596                 memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
 597                 memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
 598                 memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
 599                 memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
 600
 601                 mddev->max_disks = MD_SB_DISKS;
 602         } else {
 603                 __u64 ev1;
 604                 ev1 = md_event(sb);
 605                 ++ev1;
 606                 if (ev1 < mddev->events)
 607                         return -EINVAL;
 608         }
 609         if (mddev->level != LEVEL_MULTIPATH) {
 610                 rdev->raid_disk = -1;
 611                 rdev->in_sync = rdev->faulty = 0;
 612                 desc = sb->disks + rdev->desc_nr;
 613
 614                 if (desc->state & (1<<MD_DISK_FAULTY))
 615                         rdev->faulty = 1;
 616                 else if (desc->state & (1<<MD_DISK_SYNC) &&
 617                          desc->raid_disk < mddev->raid_disks) {
 618                         rdev->in_sync = 1;
 619                         rdev->raid_disk = desc->raid_disk;
 620                 }
 621         }
 622         return 0;
 623 }
 624
 625 /*
 626  * sync_super for 0.90.0
 627  */
 628 static void super_90_sync(mddev_t *mddev, mdk_rdev_t *rdev)
 629 {
 630         mdp_super_t *sb;
 631         struct list_head *tmp;
 632         mdk_rdev_t *rdev2;
 633         int next_spare = mddev->raid_disks;
 634
 635         /* make rdev->sb match mddev data..
 636          *
 637          * 1/ zero out disks
 638          * 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
 639          * 3/ any empty disks < next_spare become removed
 640          *
 641          * disks[0] gets initialised to REMOVED because
 642          * we cannot be sure from other fields if it has
 643          * been initialised or not.
 644          */
 645         int i;
 646         int active=0, working=0,failed=0,spare=0,nr_disks=0;
 647
 648         sb = (mdp_super_t*)page_address(rdev->sb_page);
 649
 650         memset(sb, 0, sizeof(*sb));
 651
 652         sb->md_magic = MD_SB_MAGIC;
 653         sb->major_version = mddev->major_version;
 654         sb->minor_version = mddev->minor_version;
 655         sb->patch_version = mddev->patch_version;
 656         sb->gvalid_words  = 0; /* ignored */
 657         memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
 658         memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
 659         memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
 660         memcpy(&sb->set_uuid3, mddev->uuid+12,4);
 661
 662         sb->ctime = mddev->ctime;
 663         sb->level = mddev->level;
 664         sb->size  = mddev->size;
 665         sb->raid_disks = mddev->raid_disks;
 666         sb->md_minor = mddev->md_minor;
 667         sb->not_persistent = !mddev->persistent;
 668         sb->utime = mddev->utime;
 669         sb->state = 0;
 670         sb->events_hi = (mddev->events>>32);
 671         sb->events_lo = (u32)mddev->events;
 672
 673         if (mddev->in_sync)
 674         {
 675                 sb->recovery_cp = mddev->recovery_cp;
 676                 sb->cp_events_hi = (mddev->events>>32);
 677                 sb->cp_events_lo = (u32)mddev->events;
 678                 if (mddev->recovery_cp == MaxSector)
 679                         sb->state = (1<< MD_SB_CLEAN);
 680         } else
 681                 sb->recovery_cp = 0;
 682
 683         sb->layout = mddev->layout;
 684         sb->chunk_size = mddev->chunk_size;
 685
 686         sb->disks[0].state = (1<<MD_DISK_REMOVED);
 687         ITERATE_RDEV(mddev,rdev2,tmp) {
 688                 mdp_disk_t *d;
 689                 if (rdev2->raid_disk >= 0 && rdev2->in_sync && !rdev2->faulty)
 690                         rdev2->desc_nr = rdev2->raid_disk;
 691                 else
 692                         rdev2->desc_nr = next_spare++;
 693                 d = &sb->disks[rdev2->desc_nr];
 694                 nr_disks++;
 695                 d->number = rdev2->desc_nr;
 696                 d->major = MAJOR(rdev2->bdev->bd_dev);
 697                 d->minor = MINOR(rdev2->bdev->bd_dev);
 698                 if (rdev2->raid_disk >= 0 && rdev->in_sync && !rdev2->faulty)
 699                         d->raid_disk = rdev2->raid_disk;
 700                 else
 701                         d->raid_disk = rdev2->desc_nr; /* compatibility */
 702                 if (rdev2->faulty) {
 703                         d->state = (1<<MD_DISK_FAULTY);
 704                         failed++;
 705                 } else if (rdev2->in_sync) {
 706                         d->state = (1<<MD_DISK_ACTIVE);
 707                         d->state |= (1<<MD_DISK_SYNC);
 708                         active++;
 709                         working++;
 710                 } else {
 711                         d->state = 0;
 712                         spare++;
 713                         working++;
 714                 }
 715         }
 716
 717         /* now set the "removed" and "faulty" bits on any missing devices */
 718         for (i=0 ; i < mddev->raid_disks ; i++) {
 719                 mdp_disk_t *d = &sb->disks[i];
 720                 if (d->state == 0 && d->number == 0) {
 721                         d->number = i;
 722                         d->raid_disk = i;
 723                         d->state = (1<<MD_DISK_REMOVED);
 724                         d->state |= (1<<MD_DISK_FAULTY);
 725                         failed++;
 726                 }
 727         }
 728         sb->nr_disks = nr_disks;
 729         sb->active_disks = active;
 730         sb->working_disks = working;
 731         sb->failed_disks = failed;
 732         sb->spare_disks = spare;
 733
 734         sb->this_disk = sb->disks[rdev->desc_nr];
 735         sb->sb_csum = calc_sb_csum(sb);
 736 }
 737
 738 /*
 739  * version 1 superblock
 740  */
 741
 742 static unsigned int calc_sb_1_csum(struct mdp_superblock_1 * sb)
 743 {
 744         unsigned int disk_csum, csum;
 745         unsigned long long newcsum;
 746         int size = 256 + le32_to_cpu(sb->max_dev)*2;
 747         unsigned int *isuper = (unsigned int*)sb;
 748         int i;
 749
 750         disk_csum = sb->sb_csum;
 751         sb->sb_csum = 0;
 752         newcsum = 0;
 753         for (i=0; size>=4; size -= 4 )
 754                 newcsum += le32_to_cpu(*isuper++);
 755
 756         if (size == 2)
 757                 newcsum += le16_to_cpu(*(unsigned short*) isuper);
 758
 759         csum = (newcsum & 0xffffffff) + (newcsum >> 32);
 760         sb->sb_csum = disk_csum;
 761         return cpu_to_le32(csum);
 762 }
 763
 764 static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
 765 {
 766         struct mdp_superblock_1 *sb;
 767         int ret;
 768         sector_t sb_offset;
 769         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
 770
 771         /*
 772          * Calculate the position of the superblock.
 773          * It is always aligned to a 4K boundary and
 774          * depeding on minor_version, it can be:
 775          * 0: At least 8K, but less than 12K, from end of device
 776          * 1: At start of device
 777          * 2: 4K from start of device.
 778          */
 779         switch(minor_version) {
 780         case 0:
 781                 sb_offset = rdev->bdev->bd_inode->i_size >> 9;
 782                 sb_offset -= 8*2;
 783                 sb_offset &= ~(4*2-1);
 784                 /* convert from sectors to K */
 785                 sb_offset /= 2;
 786                 break;
 787         case 1:
 788                 sb_offset = 0;
 789                 break;
 790         case 2:
 791                 sb_offset = 4;
 792                 break;
 793         default:
 794                 return -EINVAL;
 795         }
 796         rdev->sb_offset = sb_offset;
 797
 798         ret = read_disk_sb(rdev);
 799         if (ret) return ret;
 800
 801
 802         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
 803
 804         if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
 805             sb->major_version != cpu_to_le32(1) ||
 806             le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
 807             le64_to_cpu(sb->super_offset) != (rdev->sb_offset<<1) ||
 808             sb->feature_map != 0)
 809                 return -EINVAL;
 810
 811         if (calc_sb_1_csum(sb) != sb->sb_csum) {
 812                 printk("md: invalid superblock checksum on %s\n",
 813                         bdevname(rdev->bdev,b));
 814                 return -EINVAL;
 815         }
 816         if (le64_to_cpu(sb->data_size) < 10) {
 817                 printk("md: data_size too small on %s\n",
 818                        bdevname(rdev->bdev,b));
 819                 return -EINVAL;
 820         }
 821         rdev->preferred_minor = 0xffff;
 822         rdev->data_offset = le64_to_cpu(sb->data_offset);
 823
 824         if (refdev == 0)
 825                 return 1;
 826         else {
 827                 __u64 ev1, ev2;
 828                 struct mdp_superblock_1 *refsb =
 829                         (struct mdp_superblock_1*)page_address(refdev->sb_page);
 830
 831                 if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
 832                     sb->level != refsb->level ||
 833                     sb->layout != refsb->layout ||
 834                     sb->chunksize != refsb->chunksize) {
 835                         printk(KERN_WARNING "md: %s has strangely different"
 836                                 " superblock to %s\n",
 837                                 bdevname(rdev->bdev,b),
 838                                 bdevname(refdev->bdev,b2));
 839                         return -EINVAL;
 840                 }
 841                 ev1 = le64_to_cpu(sb->events);
 842                 ev2 = le64_to_cpu(refsb->events);
 843
 844                 if (ev1 > ev2)
 845                         return 1;
 846         }
 847         if (minor_version)
 848                 rdev->size = ((rdev->bdev->bd_inode->i_size>>9) - le64_to_cpu(sb->data_offset)) / 2;
 849         else
 850                 rdev->size = rdev->sb_offset;
 851         if (rdev->size < le64_to_cpu(sb->data_size)/2)
 852                 return -EINVAL;
 853         rdev->size = le64_to_cpu(sb->data_size)/2;
 854         if (le32_to_cpu(sb->chunksize))
 855                 rdev->size &= ~((sector_t)le32_to_cpu(sb->chunksize)/2 - 1);
 856         return 0;
 857 }
 858
 859 static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
 860 {
 861         struct mdp_superblock_1 *sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
 862
 863         if (mddev->raid_disks == 0) {
 864                 mddev->major_version = 1;
 865                 mddev->patch_version = 0;
 866                 mddev->persistent = 1;
 867                 mddev->chunk_size = le32_to_cpu(sb->chunksize) << 9;
 868                 mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);
 869                 mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);
 870                 mddev->level = le32_to_cpu(sb->level);
 871                 mddev->layout = le32_to_cpu(sb->layout);
 872                 mddev->raid_disks = le32_to_cpu(sb->raid_disks);
 873                 mddev->size = le64_to_cpu(sb->size)/2;
 874                 mddev->events = le64_to_cpu(sb->events);
 875
 876                 mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
 877                 memcpy(mddev->uuid, sb->set_uuid, 16);
 878
 879                 mddev->max_disks =  (4096-256)/2;
 880         } else {
 881                 __u64 ev1;
 882                 ev1 = le64_to_cpu(sb->events);
 883                 ++ev1;
 884                 if (ev1 < mddev->events)
 885                         return -EINVAL;
 886         }
 887
 888         if (mddev->level != LEVEL_MULTIPATH) {
 889                 int role;
 890                 rdev->desc_nr = le32_to_cpu(sb->dev_number);
 891                 role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
 892                 switch(role) {
 893                 case 0xffff: /* spare */
 894                         rdev->in_sync = 0;
 895                         rdev->faulty = 0;
 896                         rdev->raid_disk = -1;
 897                         break;
 898                 case 0xfffe: /* faulty */
 899                         rdev->in_sync = 0;
 900                         rdev->faulty = 1;
 901                         rdev->raid_disk = -1;
 902                         break;
 903                 default:
 904                         rdev->in_sync = 1;
 905                         rdev->faulty = 0;
 906                         rdev->raid_disk = role;
 907                         break;
 908                 }
 909         }
 910         return 0;
 911 }
 912
 913 static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
 914 {
 915         struct mdp_superblock_1 *sb;
 916         struct list_head *tmp;
 917         mdk_rdev_t *rdev2;
 918         int max_dev, i;
 919         /* make rdev->sb match mddev and rdev data. */
 920
 921         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
 922
 923         sb->feature_map = 0;
 924         sb->pad0 = 0;
 925         memset(sb->pad1, 0, sizeof(sb->pad1));
 926         memset(sb->pad2, 0, sizeof(sb->pad2));
 927         memset(sb->pad3, 0, sizeof(sb->pad3));
 928
 929         sb->utime = cpu_to_le64((__u64)mddev->utime);
 930         sb->events = cpu_to_le64(mddev->events);
 931         if (mddev->in_sync)
 932                 sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
 933         else
 934                 sb->resync_offset = cpu_to_le64(0);
 935
 936         max_dev = 0;
 937         ITERATE_RDEV(mddev,rdev2,tmp)
 938                 if (rdev2->desc_nr+1 > max_dev)
 939                         max_dev = rdev2->desc_nr+1;
 940
 941         sb->max_dev = cpu_to_le32(max_dev);
 942         for (i=0; i<max_dev;i++)
 943                 sb->dev_roles[i] = cpu_to_le16(0xfffe);
 944
 945         ITERATE_RDEV(mddev,rdev2,tmp) {
 946                 i = rdev2->desc_nr;
 947                 if (rdev2->faulty)
 948                         sb->dev_roles[i] = cpu_to_le16(0xfffe);
 949                 else if (rdev2->in_sync)
 950                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
 951                 else
 952                         sb->dev_roles[i] = cpu_to_le16(0xffff);
 953         }
 954
 955         sb->recovery_offset = cpu_to_le64(0); /* not supported yet */
 956         sb->sb_csum = calc_sb_1_csum(sb);
 957 }
 958
 959
 960 static struct super_type super_types[] = {
 961         [0] = {
 962                 .name   = "0.90.0",
 963                 .owner  = THIS_MODULE,
 964                 .load_super     = super_90_load,
 965                 .validate_super = super_90_validate,
 966                 .sync_super     = super_90_sync,
 967         },
 968         [1] = {
 969                 .name   = "md-1",
 970                 .owner  = THIS_MODULE,
 971                 .load_super     = super_1_load,
 972                 .validate_super = super_1_validate,
 973                 .sync_super     = super_1_sync,
 974         },
 975 };
 976
 977 static mdk_rdev_t * match_dev_unit(mddev_t *mddev, mdk_rdev_t *dev)
 978 {
 979         struct list_head *tmp;
 980         mdk_rdev_t *rdev;
 981
 982         ITERATE_RDEV(mddev,rdev,tmp)
 983                 if (rdev->bdev->bd_contains == dev->bdev->bd_contains)
 984                         return rdev;
 985
 986         return NULL;
 987 }
 988
 989 static int match_mddev_units(mddev_t *mddev1, mddev_t *mddev2)
 990 {
 991         struct list_head *tmp;
 992         mdk_rdev_t *rdev;
 993
 994         ITERATE_RDEV(mddev1,rdev,tmp)
 995                 if (match_dev_unit(mddev2, rdev))
 996                         return 1;
 997
 998         return 0;
 999 }
1000
1001 static LIST_HEAD(pending_raid_disks);
1002
1003 static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
1004 {
1005         mdk_rdev_t *same_pdev;
1006         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1007
1008         if (rdev->mddev) {
1009                 MD_BUG();
1010                 return -EINVAL;
1011         }
1012         same_pdev = match_dev_unit(mddev, rdev);
1013         if (same_pdev)
1014                 printk(KERN_WARNING
1015                         "%s: WARNING: %s appears to be on the same physical"
1016                         " disk as %s. True\n     protection against single-disk"
1017                         " failure might be compromised.\n",
1018                         mdname(mddev), bdevname(rdev->bdev,b),
1019                         bdevname(same_pdev->bdev,b2));
1020
1021         /* Verify rdev->desc_nr is unique.
1022          * If it is -1, assign a free number, else
1023          * check number is not in use
1024          */
1025         if (rdev->desc_nr < 0) {
1026                 int choice = 0;
1027                 if (mddev->pers) choice = mddev->raid_disks;
1028                 while (find_rdev_nr(mddev, choice))
1029                         choice++;
1030                 rdev->desc_nr = choice;
1031         } else {
1032                 if (find_rdev_nr(mddev, rdev->desc_nr))
1033                         return -EBUSY;
1034         }
1035
1036         list_add(&rdev->same_set, &mddev->disks);
1037         rdev->mddev = mddev;
1038         printk(KERN_INFO "md: bind<%s>\n", bdevname(rdev->bdev,b));
1039         return 0;
1040 }
1041
1042 static void unbind_rdev_from_array(mdk_rdev_t * rdev)
1043 {
1044         char b[BDEVNAME_SIZE];
1045         if (!rdev->mddev) {
1046                 MD_BUG();
1047                 return;
1048         }
1049         list_del_init(&rdev->same_set);
1050         printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
1051         rdev->mddev = NULL;
1052 }
1053
1054 /*
1055  * prevent the device from being mounted, repartitioned or
1056  * otherwise reused by a RAID array (or any other kernel
1057  * subsystem), by bd_claiming the device.
1058  */
1059 static int lock_rdev(mdk_rdev_t *rdev, dev_t dev)
1060 {
1061         int err = 0;
1062         struct block_device *bdev;
1063         char b[BDEVNAME_SIZE];
1064
1065         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
1066         if (IS_ERR(bdev)) {
1067                 printk(KERN_ERR "md: could not open %s.\n",
1068                         __bdevname(dev, b));
1069                 return PTR_ERR(bdev);
1070         }
1071         err = bd_claim(bdev, rdev);
1072         if (err) {
1073                 printk(KERN_ERR "md: could not bd_claim %s.\n",
1074                         bdevname(bdev, b));
1075                 blkdev_put(bdev);
1076                 return err;
1077         }
1078         rdev->bdev = bdev;
1079         return err;
1080 }
1081
1082 static void unlock_rdev(mdk_rdev_t *rdev)
1083 {
1084         struct block_device *bdev = rdev->bdev;
1085         rdev->bdev = NULL;
1086         if (!bdev)
1087                 MD_BUG();
1088         bd_release(bdev);
1089         blkdev_put(bdev);
1090 }
1091
1092 void md_autodetect_dev(dev_t dev);
1093
1094 static void export_rdev(mdk_rdev_t * rdev)
1095 {
1096         char b[BDEVNAME_SIZE];
1097         printk(KERN_INFO "md: export_rdev(%s)\n",
1098                 bdevname(rdev->bdev,b));
1099         if (rdev->mddev)
1100                 MD_BUG();
1101         free_disk_sb(rdev);
1102         list_del_init(&rdev->same_set);
1103 #ifndef MODULE
1104         md_autodetect_dev(rdev->bdev->bd_dev);
1105 #endif
1106         unlock_rdev(rdev);
1107         kfree(rdev);
1108 }
1109
1110 static void kick_rdev_from_array(mdk_rdev_t * rdev)
1111 {
1112         unbind_rdev_from_array(rdev);
1113         export_rdev(rdev);
1114 }
1115
1116 static void export_array(mddev_t *mddev)
1117 {
1118         struct list_head *tmp;
1119         mdk_rdev_t *rdev;
1120
1121         ITERATE_RDEV(mddev,rdev,tmp) {
1122                 if (!rdev->mddev) {
1123                         MD_BUG();
1124                         continue;
1125                 }
1126                 kick_rdev_from_array(rdev);
1127         }
1128         if (!list_empty(&mddev->disks))
1129                 MD_BUG();
1130         mddev->raid_disks = 0;
1131         mddev->major_version = 0;
1132 }
1133
1134 static void print_desc(mdp_disk_t *desc)
1135 {
1136         printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
1137                 desc->major,desc->minor,desc->raid_disk,desc->state);
1138 }
1139
1140 static void print_sb(mdp_super_t *sb)
1141 {
1142         int i;
1143
1144         printk(KERN_INFO
1145                 "md:  SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
1146                 sb->major_version, sb->minor_version, sb->patch_version,
1147                 sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
1148                 sb->ctime);
1149         printk(KERN_INFO "md:     L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
1150                 sb->level, sb->size, sb->nr_disks, sb->raid_disks,
1151                 sb->md_minor, sb->layout, sb->chunk_size);
1152         printk(KERN_INFO "md:     UT:%08x ST:%d AD:%d WD:%d"
1153                 " FD:%d SD:%d CSUM:%08x E:%08lx\n",
1154                 sb->utime, sb->state, sb->active_disks, sb->working_disks,
1155                 sb->failed_disks, sb->spare_disks,
1156                 sb->sb_csum, (unsigned long)sb->events_lo);
1157
1158         printk(KERN_INFO);
1159         for (i = 0; i < MD_SB_DISKS; i++) {
1160                 mdp_disk_t *desc;
1161
1162                 desc = sb->disks + i;
1163                 if (desc->number || desc->major || desc->minor ||
1164                     desc->raid_disk || (desc->state && (desc->state != 4))) {
1165                         printk("     D %2d: ", i);
1166                         print_desc(desc);
1167                 }
1168         }
1169         printk(KERN_INFO "md:     THIS: ");
1170         print_desc(&sb->this_disk);
1171
1172 }
1173
1174 static void print_rdev(mdk_rdev_t *rdev)
1175 {
1176         char b[BDEVNAME_SIZE];
1177         printk(KERN_INFO "md: rdev %s, SZ:%08llu F:%d S:%d DN:%u\n",
1178                 bdevname(rdev->bdev,b), (unsigned long long)rdev->size,
1179                 rdev->faulty, rdev->in_sync, rdev->desc_nr);
1180         if (rdev->sb_loaded) {
1181                 printk(KERN_INFO "md: rdev superblock:\n");
1182                 print_sb((mdp_super_t*)page_address(rdev->sb_page));
1183         } else
1184                 printk(KERN_INFO "md: no rdev superblock!\n");
1185 }
1186
1187 void md_print_devices(void)
1188 {
1189         struct list_head *tmp, *tmp2;
1190         mdk_rdev_t *rdev;
1191         mddev_t *mddev;
1192         char b[BDEVNAME_SIZE];
1193
1194         printk("\n");
1195         printk("md:     **********************************\n");
1196         printk("md:     * <COMPLETE RAID STATE PRINTOUT> *\n");
1197         printk("md:     **********************************\n");
1198         ITERATE_MDDEV(mddev,tmp) {
1199                 printk("%s: ", mdname(mddev));
1200
1201                 ITERATE_RDEV(mddev,rdev,tmp2)
1202                         printk("<%s>", bdevname(rdev->bdev,b));
1203                 printk("\n");
1204
1205                 ITERATE_RDEV(mddev,rdev,tmp2)
1206                         print_rdev(rdev);
1207         }
1208         printk("md:     **********************************\n");
1209         printk("\n");
1210 }
1211
1212
1213 static int write_disk_sb(mdk_rdev_t * rdev)
1214 {
1215         char b[BDEVNAME_SIZE];
1216         if (!rdev->sb_loaded) {
1217                 MD_BUG();
1218                 return 1;
1219         }
1220         if (rdev->faulty) {
1221                 MD_BUG();
1222                 return 1;
1223         }
1224
1225         dprintk(KERN_INFO "(write) %s's sb offset: %llu\n",
1226                 bdevname(rdev->bdev,b),
1227                (unsigned long long)rdev->sb_offset);
1228
1229         if (sync_page_io(rdev->bdev, rdev->sb_offset<<1, MD_SB_BYTES, rdev->sb_page, WRITE))
1230                 return 0;
1231
1232         printk("md: write_disk_sb failed for device %s\n",
1233                 bdevname(rdev->bdev,b));
1234         return 1;
1235 }
1236
1237 static void sync_sbs(mddev_t * mddev)
1238 {
1239         mdk_rdev_t *rdev;
1240         struct list_head *tmp;
1241
1242         ITERATE_RDEV(mddev,rdev,tmp) {
1243                 super_types[mddev->major_version].
1244                         sync_super(mddev, rdev);
1245                 rdev->sb_loaded = 1;
1246         }
1247 }
1248
1249 static void md_update_sb(mddev_t * mddev)
1250 {
1251         int err, count = 100;
1252         struct list_head *tmp;
1253         mdk_rdev_t *rdev;
1254
1255         mddev->sb_dirty = 0;
1256 repeat:
1257         mddev->utime = get_seconds();
1258         mddev->events ++;
1259
1260         if (!mddev->events) {
1261                 /*
1262                  * oops, this 64-bit counter should never wrap.
1263                  * Either we are in around ~1 trillion A.C., assuming
1264                  * 1 reboot per second, or we have a bug:
1265                  */
1266                 MD_BUG();
1267                 mddev->events --;
1268         }
1269         sync_sbs(mddev);
1270
1271         /*
1272          * do not write anything to disk if using
1273          * nonpersistent superblocks
1274          */
1275         if (!mddev->persistent)
1276                 return;
1277
1278         dprintk(KERN_INFO
1279                 "md: updating %s RAID superblock on device (in sync %d)\n",
1280                 mdname(mddev),mddev->in_sync);
1281
1282         err = 0;
1283         ITERATE_RDEV(mddev,rdev,tmp) {
1284                 char b[BDEVNAME_SIZE];
1285                 dprintk(KERN_INFO "md: ");
1286                 if (rdev->faulty)
1287                         dprintk("(skipping faulty ");
1288
1289                 dprintk("%s ", bdevname(rdev->bdev,b));
1290                 if (!rdev->faulty) {
1291                         err += write_disk_sb(rdev);
1292                 } else
1293                         dprintk(")\n");
1294                 if (!err && mddev->level == LEVEL_MULTIPATH)
1295                         /* only need to write one superblock... */
1296                         break;
1297         }
1298         if (err) {
1299                 if (--count) {
1300                         printk(KERN_ERR "md: errors occurred during superblock"
1301                                 " update, repeating\n");
1302                         goto repeat;
1303                 }
1304                 printk(KERN_ERR \
1305                         "md: excessive errors occurred during superblock update, exiting\n");
1306         }
1307 }
1308
1309 /*
1310  * Import a device. If 'super_format' >= 0, then sanity check the superblock
1311  *
1312  * mark the device faulty if:
1313  *
1314  *   - the device is nonexistent (zero size)
1315  *   - the device has no valid superblock
1316  *
1317  * a faulty rdev _never_ has rdev->sb set.
1318  */
1319 static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_minor)
1320 {
1321         char b[BDEVNAME_SIZE];
1322         int err;
1323         mdk_rdev_t *rdev;
1324         sector_t size;
1325
1326         rdev = (mdk_rdev_t *) kmalloc(sizeof(*rdev), GFP_KERNEL);
1327         if (!rdev) {
1328                 printk(KERN_ERR "md: could not alloc mem for new device!\n");
1329                 return ERR_PTR(-ENOMEM);
1330         }
1331         memset(rdev, 0, sizeof(*rdev));
1332
1333         if ((err = alloc_disk_sb(rdev)))
1334                 goto abort_free;
1335
1336         err = lock_rdev(rdev, newdev);
1337         if (err)
1338                 goto abort_free;
1339
1340         rdev->desc_nr = -1;
1341         rdev->faulty = 0;
1342         rdev->in_sync = 0;
1343         rdev->data_offset = 0;
1344         atomic_set(&rdev->nr_pending, 0);
1345
1346         size = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
1347         if (!size) {
1348                 printk(KERN_WARNING
1349                         "md: %s has zero or unknown size, marking faulty!\n",
1350                         bdevname(rdev->bdev,b));
1351                 err = -EINVAL;
1352                 goto abort_free;
1353         }
1354
1355         if (super_format >= 0) {
1356                 err = super_types[super_format].
1357                         load_super(rdev, NULL, super_minor);
1358                 if (err == -EINVAL) {
1359                         printk(KERN_WARNING
1360                                 "md: %s has invalid sb, not importing!\n",
1361                                 bdevname(rdev->bdev,b));
1362                         goto abort_free;
1363                 }
1364                 if (err < 0) {
1365                         printk(KERN_WARNING
1366                                 "md: could not read %s's sb, not importing!\n",
1367                                 bdevname(rdev->bdev,b));
1368                         goto abort_free;
1369                 }
1370         }
1371         INIT_LIST_HEAD(&rdev->same_set);
1372
1373         return rdev;
1374
1375 abort_free:
1376         if (rdev->sb_page) {
1377                 if (rdev->bdev)
1378                         unlock_rdev(rdev);
1379                 free_disk_sb(rdev);
1380         }
1381         kfree(rdev);
1382         return ERR_PTR(err);
1383 }
1384
1385 /*
1386  * Check a full RAID array for plausibility
1387  */
1388
1389
1390 static void analyze_sbs(mddev_t * mddev)
1391 {
1392         int i;
1393         struct list_head *tmp;
1394         mdk_rdev_t *rdev, *freshest;
1395         char b[BDEVNAME_SIZE];
1396
1397         freshest = NULL;
1398         ITERATE_RDEV(mddev,rdev,tmp)
1399                 switch (super_types[mddev->major_version].
1400                         load_super(rdev, freshest, mddev->minor_version)) {
1401                 case 1:
1402                         freshest = rdev;
1403                         break;
1404                 case 0:
1405                         break;
1406                 default:
1407                         printk( KERN_ERR \
1408                                 "md: fatal superblock inconsistency in %s"
1409                                 " -- removing from array\n",
1410                                 bdevname(rdev->bdev,b));
1411                         kick_rdev_from_array(rdev);
1412                 }
1413
1414
1415         super_types[mddev->major_version].
1416                 validate_super(mddev, freshest);
1417
1418         i = 0;
1419         ITERATE_RDEV(mddev,rdev,tmp) {
1420                 if (rdev != freshest)
1421                         if (super_types[mddev->major_version].
1422                             validate_super(mddev, rdev)) {
1423                                 printk(KERN_WARNING "md: kicking non-fresh %s"
1424                                         " from array!\n",
1425                                         bdevname(rdev->bdev,b));
1426                                 kick_rdev_from_array(rdev);
1427                                 continue;
1428                         }
1429                 if (mddev->level == LEVEL_MULTIPATH) {
1430                         rdev->desc_nr = i++;
1431                         rdev->raid_disk = rdev->desc_nr;
1432                         rdev->in_sync = 1;
1433                 }
1434         }
1435
1436
1437
1438         if (mddev->recovery_cp != MaxSector &&
1439             mddev->level >= 1)
1440                 printk(KERN_ERR "md: %s: raid array is not clean"
1441                        " -- starting background reconstruction\n",
1442                        mdname(mddev));
1443
1444 }
1445
1446 int mdp_major = 0;
1447
1448 static struct kobject *md_probe(dev_t dev, int *part, void *data)
1449 {
1450         static DECLARE_MUTEX(disks_sem);
1451         mddev_t *mddev = mddev_find(dev);
1452         struct gendisk *disk;
1453         int partitioned = (MAJOR(dev) != MD_MAJOR);
1454         int shift = partitioned ? MdpMinorShift : 0;
1455         int unit = MINOR(dev) >> shift;
1456
1457         if (!mddev)
1458                 return NULL;
1459
1460         down(&disks_sem);
1461         if (mddev->gendisk) {
1462                 up(&disks_sem);
1463                 mddev_put(mddev);
1464                 return NULL;
1465         }
1466         disk = alloc_disk(1 << shift);
1467         if (!disk) {
1468                 up(&disks_sem);
1469                 mddev_put(mddev);
1470                 return NULL;
1471         }
1472         disk->major = MAJOR(dev);
1473         disk->first_minor = unit << shift;
1474         if (partitioned) {
1475                 sprintf(disk->disk_name, "md_d%d", unit);
1476                 sprintf(disk->devfs_name, "md/d%d", unit);
1477         } else {
1478                 sprintf(disk->disk_name, "md%d", unit);
1479                 sprintf(disk->devfs_name, "md/%d", unit);
1480         }
1481         disk->fops = &md_fops;
1482         disk->private_data = mddev;
1483         disk->queue = mddev->queue;
1484         add_disk(disk);
1485         mddev->gendisk = disk;
1486         up(&disks_sem);
1487         return NULL;
1488 }
1489
1490 void md_wakeup_thread(mdk_thread_t *thread);
1491
1492 static void md_safemode_timeout(unsigned long data)
1493 {
1494         mddev_t *mddev = (mddev_t *) data;
1495
1496         mddev->safemode = 1;
1497         md_wakeup_thread(mddev->thread);
1498 }
1499
1500
1501 static int do_md_run(mddev_t * mddev)
1502 {
1503         int pnum, err;
1504         int chunk_size;
1505         struct list_head *tmp;
1506         mdk_rdev_t *rdev;
1507         struct gendisk *disk;
1508         char b[BDEVNAME_SIZE];
1509
1510         if (list_empty(&mddev->disks))
1511                 /* cannot run an array with no devices.. */
1512                 return -EINVAL;
1513
1514         if (mddev->pers)
1515                 return -EBUSY;
1516
1517         /*
1518          * Analyze all RAID superblock(s)
1519          */
1520         if (!mddev->raid_disks)
1521                 analyze_sbs(mddev);
1522
1523         chunk_size = mddev->chunk_size;
1524         pnum = level_to_pers(mddev->level);
1525
1526         if ((pnum != MULTIPATH) && (pnum != RAID1)) {
1527                 if (!chunk_size) {
1528                         /*
1529                          * 'default chunksize' in the old md code used to
1530                          * be PAGE_SIZE, baaad.
1531                          * we abort here to be on the safe side. We don't
1532                          * want to continue the bad practice.
1533                          */
1534                         printk(KERN_ERR
1535                                 "no chunksize specified, see 'man raidtab'\n");
1536                         return -EINVAL;
1537                 }
1538                 if (chunk_size > MAX_CHUNK_SIZE) {
1539                         printk(KERN_ERR "too big chunk_size: %d > %d\n",
1540                                 chunk_size, MAX_CHUNK_SIZE);
1541                         return -EINVAL;
1542                 }
1543                 /*
1544                  * chunk-size has to be a power of 2 and multiples of PAGE_SIZE
1545                  */
1546                 if ( (1 << ffz(~chunk_size)) != chunk_size) {
1547                         printk(KERN_ERR "chunk_size of %d not valid\n", chunk_size);
1548                         return -EINVAL;
1549                 }
1550                 if (chunk_size < PAGE_SIZE) {
1551                         printk(KERN_ERR "too small chunk_size: %d < %ld\n",
1552                                 chunk_size, PAGE_SIZE);
1553                         return -EINVAL;
1554                 }
1555
1556                 /* devices must have minimum size of one chunk */
1557                 ITERATE_RDEV(mddev,rdev,tmp) {
1558                         if (rdev->faulty)
1559                                 continue;
1560                         if (rdev->size < chunk_size / 1024) {
1561                                 printk(KERN_WARNING
1562                                         "md: Dev %s smaller than chunk_size:"
1563                                         " %lluk < %dk\n",
1564                                         bdevname(rdev->bdev,b),
1565                                         (unsigned long long)rdev->size,
1566                                         chunk_size / 1024);
1567                                 return -EINVAL;
1568                         }
1569                 }
1570         }
1571
1572 #ifdef CONFIG_KMOD
1573         if (!pers[pnum])
1574         {
1575                 request_module("md-personality-%d", pnum);
1576         }
1577 #endif
1578
1579         /*
1580          * Drop all container device buffers, from now on
1581          * the only valid external interface is through the md
1582          * device.
1583          * Also find largest hardsector size
1584          */
1585         ITERATE_RDEV(mddev,rdev,tmp) {
1586                 if (rdev->faulty)
1587                         continue;
1588                 sync_blockdev(rdev->bdev);
1589                 invalidate_bdev(rdev->bdev, 0);
1590         }
1591
1592         md_probe(mddev->unit, NULL, NULL);
1593         disk = mddev->gendisk;
1594         if (!disk)
1595                 return -ENOMEM;
1596
1597         spin_lock(&pers_lock);
1598         if (!pers[pnum] || !try_module_get(pers[pnum]->owner)) {
1599                 spin_unlock(&pers_lock);
1600                 printk(KERN_WARNING "md: personality %d is not loaded!\n",
1601                        pnum);
1602                 return -EINVAL;
1603         }
1604
1605         mddev->pers = pers[pnum];
1606         spin_unlock(&pers_lock);
1607
1608         mddev->resync_max_sectors = mddev->size << 1; /* may be over-ridden by personality */
1609
1610         err = mddev->pers->run(mddev);
1611         if (err) {
1612                 printk(KERN_ERR "md: pers->run() failed ...\n");
1613                 module_put(mddev->pers->owner);
1614                 mddev->pers = NULL;
1615                 return -EINVAL;
1616         }
1617         atomic_set(&mddev->writes_pending,0);
1618         mddev->safemode = 0;
1619         mddev->safemode_timer.function = md_safemode_timeout;
1620         mddev->safemode_timer.data = (unsigned long) mddev;
1621         mddev->safemode_delay = (20 * HZ)/1000 +1; /* 20 msec delay */
1622         mddev->in_sync = 1;
1623
1624         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
1625
1626         if (mddev->sb_dirty)
1627                 md_update_sb(mddev);
1628
1629         set_capacity(disk, mddev->array_size<<1);
1630
1631         /* If we call blk_queue_make_request here, it will
1632          * re-initialise max_sectors etc which may have been
1633          * refined inside -> run.  So just set the bits we need to set.
1634          * Most initialisation happended when we called
1635          * blk_queue_make_request(..., md_fail_request)
1636          * earlier.
1637          */
1638         mddev->queue->queuedata = mddev;
1639         mddev->queue->make_request_fn = mddev->pers->make_request;
1640
1641         mddev->changed = 1;
1642         return 0;
1643 }
1644
1645 static int restart_array(mddev_t *mddev)
1646 {
1647         struct gendisk *disk = mddev->gendisk;
1648         int err;
1649
1650         /*
1651          * Complain if it has no devices
1652          */
1653         err = -ENXIO;
1654         if (list_empty(&mddev->disks))
1655                 goto out;
1656
1657         if (mddev->pers) {
1658                 err = -EBUSY;
1659                 if (!mddev->ro)
1660                         goto out;
1661
1662                 mddev->safemode = 0;
1663                 mddev->ro = 0;
1664                 set_disk_ro(disk, 0);
1665
1666                 printk(KERN_INFO "md: %s switched to read-write mode.\n",
1667                         mdname(mddev));
1668                 /*
1669                  * Kick recovery or resync if necessary
1670                  */
1671                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
1672                 md_wakeup_thread(mddev->thread);
1673                 err = 0;
1674         } else {
1675                 printk(KERN_ERR "md: %s has no personality assigned.\n",
1676                         mdname(mddev));
1677                 err = -EINVAL;
1678         }
1679
1680 out:
1681         return err;
1682 }
1683
1684 static int do_md_stop(mddev_t * mddev, int ro)
1685 {
1686         int err = 0;
1687         struct gendisk *disk = mddev->gendisk;
1688
1689         if (mddev->pers) {
1690                 if (atomic_read(&mddev->active)>2) {
1691                         printk("md: %s still in use.\n",mdname(mddev));
1692                         return -EBUSY;
1693                 }
1694
1695                 if (mddev->sync_thread) {
1696                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
1697                         md_unregister_thread(mddev->sync_thread);
1698                         mddev->sync_thread = NULL;
1699                 }
1700
1701                 del_timer_sync(&mddev->safemode_timer);
1702
1703                 invalidate_partition(disk, 0);
1704
1705                 if (ro) {
1706                         err  = -ENXIO;
1707                         if (mddev->ro)
1708                                 goto out;
1709                         mddev->ro = 1;
1710                 } else {
1711                         if (mddev->ro)
1712                                 set_disk_ro(disk, 0);
1713                         blk_queue_make_request(mddev->queue, md_fail_request);
1714                         mddev->pers->stop(mddev);
1715                         module_put(mddev->pers->owner);
1716                         mddev->pers = NULL;
1717                         if (mddev->ro)
1718                                 mddev->ro = 0;
1719                 }
1720                 if (!mddev->in_sync) {
1721                         /* mark array as shutdown cleanly */
1722                         mddev->in_sync = 1;
1723                         md_update_sb(mddev);
1724                 }
1725                 if (ro)
1726                         set_disk_ro(disk, 1);
1727         }
1728         /*
1729          * Free resources if final stop
1730          */
1731         if (!ro) {
1732                 struct gendisk *disk;
1733                 printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
1734
1735                 export_array(mddev);
1736
1737                 mddev->array_size = 0;
1738                 disk = mddev->gendisk;
1739                 if (disk)
1740                         set_capacity(disk, 0);
1741                 mddev->changed = 1;
1742         } else
1743                 printk(KERN_INFO "md: %s switched to read-only mode.\n",
1744                         mdname(mddev));
1745         err = 0;
1746 out:
1747         return err;
1748 }
1749
1750 static void autorun_array(mddev_t *mddev)
1751 {
1752         mdk_rdev_t *rdev;
1753         struct list_head *tmp;
1754         int err;
1755
1756         if (list_empty(&mddev->disks))
1757                 return;
1758
1759         printk(KERN_INFO "md: running: ");
1760
1761         ITERATE_RDEV(mddev,rdev,tmp) {
1762                 char b[BDEVNAME_SIZE];
1763                 printk("<%s>", bdevname(rdev->bdev,b));
1764         }
1765         printk("\n");
1766
1767         err = do_md_run (mddev);
1768         if (err) {
1769                 printk(KERN_WARNING "md: do_md_run() returned %d\n", err);
1770                 do_md_stop (mddev, 0);
1771         }
1772 }
1773
1774 /*
1775  * lets try to run arrays based on all disks that have arrived
1776  * until now. (those are in pending_raid_disks)
1777  *
1778  * the method: pick the first pending disk, collect all disks with
1779  * the same UUID, remove all from the pending list and put them into
1780  * the 'same_array' list. Then order this list based on superblock
1781  * update time (freshest comes first), kick out 'old' disks and
1782  * compare superblocks. If everything's fine then run it.
1783  *
1784  * If "unit" is allocated, then bump its reference count
1785  */
1786 static void autorun_devices(int part)
1787 {
1788         struct list_head candidates;
1789         struct list_head *tmp;
1790         mdk_rdev_t *rdev0, *rdev;
1791         mddev_t *mddev;
1792         char b[BDEVNAME_SIZE];
1793
1794         printk(KERN_INFO "md: autorun ...\n");
1795         while (!list_empty(&pending_raid_disks)) {
1796                 dev_t dev;
1797                 rdev0 = list_entry(pending_raid_disks.next,
1798                                          mdk_rdev_t, same_set);
1799
1800                 printk(KERN_INFO "md: considering %s ...\n",
1801                         bdevname(rdev0->bdev,b));
1802                 INIT_LIST_HEAD(&candidates);
1803                 ITERATE_RDEV_PENDING(rdev,tmp)
1804                         if (super_90_load(rdev, rdev0, 0) >= 0) {
1805                                 printk(KERN_INFO "md:  adding %s ...\n",
1806                                         bdevname(rdev->bdev,b));
1807                                 list_move(&rdev->same_set, &candidates);
1808                         }
1809                 /*
1810                  * now we have a set of devices, with all of them having
1811                  * mostly sane superblocks. It's time to allocate the
1812                  * mddev.
1813                  */
1814                 if (rdev0->preferred_minor < 0 || rdev0->preferred_minor >= MAX_MD_DEVS) {
1815                         printk(KERN_INFO "md: unit number in %s is bad: %d\n",
1816                                bdevname(rdev0->bdev, b), rdev0->preferred_minor);
1817                         break;
1818                 }
1819                 if (part)
1820                         dev = MKDEV(mdp_major,
1821                                     rdev0->preferred_minor << MdpMinorShift);
1822                 else
1823                         dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
1824
1825                 md_probe(dev, NULL, NULL);
1826                 mddev = mddev_find(dev);
1827                 if (!mddev) {
1828                         printk(KERN_ERR
1829                                 "md: cannot allocate memory for md drive.\n");
1830                         break;
1831                 }
1832                 if (mddev_lock(mddev))
1833                         printk(KERN_WARNING "md: %s locked, cannot run\n",
1834                                mdname(mddev));
1835                 else if (mddev->raid_disks || mddev->major_version
1836                          || !list_empty(&mddev->disks)) {
1837                         printk(KERN_WARNING
1838                                 "md: %s already running, cannot run %s\n",
1839                                 mdname(mddev), bdevname(rdev0->bdev,b));
1840                         mddev_unlock(mddev);
1841                 } else {
1842                         printk(KERN_INFO "md: created %s\n", mdname(mddev));
1843                         ITERATE_RDEV_GENERIC(candidates,rdev,tmp) {
1844                                 list_del_init(&rdev->same_set);
1845                                 if (bind_rdev_to_array(rdev, mddev))
1846                                         export_rdev(rdev);
1847                         }
1848                         autorun_array(mddev);
1849                         mddev_unlock(mddev);
1850                 }
1851                 /* on success, candidates will be empty, on error
1852                  * it won't...
1853                  */
1854                 ITERATE_RDEV_GENERIC(candidates,rdev,tmp)
1855                         export_rdev(rdev);
1856                 mddev_put(mddev);
1857         }
1858         printk(KERN_INFO "md: ... autorun DONE.\n");
1859 }
1860
1861 /*
1862  * import RAID devices based on one partition
1863  * if possible, the array gets run as well.
1864  */
1865
1866 static int autostart_array(dev_t startdev)
1867 {
1868         char b[BDEVNAME_SIZE];
1869         int err = -EINVAL, i;
1870         mdp_super_t *sb = NULL;
1871         mdk_rdev_t *start_rdev = NULL, *rdev;
1872
1873         start_rdev = md_import_device(startdev, 0, 0);
1874         if (IS_ERR(start_rdev))
1875                 return err;
1876
1877
1878         /* NOTE: this can only work for 0.90.0 superblocks */
1879         sb = (mdp_super_t*)page_address(start_rdev->sb_page);
1880         if (sb->major_version != 0 ||
1881             sb->minor_version != 90 ) {
1882                 printk(KERN_WARNING "md: can only autostart 0.90.0 arrays\n");
1883                 export_rdev(start_rdev);
1884                 return err;
1885         }
1886
1887         if (start_rdev->faulty) {
1888                 printk(KERN_WARNING
1889                         "md: can not autostart based on faulty %s!\n",
1890                         bdevname(start_rdev->bdev,b));
1891                 export_rdev(start_rdev);
1892                 return err;
1893         }
1894         list_add(&start_rdev->same_set, &pending_raid_disks);
1895
1896         for (i = 0; i < MD_SB_DISKS; i++) {
1897                 mdp_disk_t *desc = sb->disks + i;
1898                 dev_t dev = MKDEV(desc->major, desc->minor);
1899
1900                 if (!dev)
1901                         continue;
1902                 if (dev == startdev)
1903                         continue;
1904                 if (MAJOR(dev) != desc->major || MINOR(dev) != desc->minor)
1905                         continue;
1906                 rdev = md_import_device(dev, 0, 0);
1907                 if (IS_ERR(rdev))
1908                         continue;
1909
1910                 list_add(&rdev->same_set, &pending_raid_disks);
1911         }
1912
1913         /*
1914          * possibly return codes
1915          */
1916         autorun_devices(0);
1917         return 0;
1918
1919 }
1920
1921
1922 static int get_version(void __user * arg)
1923 {
1924         mdu_version_t ver;
1925
1926         ver.major = MD_MAJOR_VERSION;
1927         ver.minor = MD_MINOR_VERSION;
1928         ver.patchlevel = MD_PATCHLEVEL_VERSION;
1929
1930         if (copy_to_user(arg, &ver, sizeof(ver)))
1931                 return -EFAULT;
1932
1933         return 0;
1934 }
1935
1936 static int get_array_info(mddev_t * mddev, void __user * arg)
1937 {
1938         mdu_array_info_t info;
1939         int nr,working,active,failed,spare;
1940         mdk_rdev_t *rdev;
1941         struct list_head *tmp;
1942
1943         nr=working=active=failed=spare=0;
1944         ITERATE_RDEV(mddev,rdev,tmp) {
1945                 nr++;
1946                 if (rdev->faulty)
1947                         failed++;
1948                 else {
1949                         working++;
1950                         if (rdev->in_sync)
1951                                 active++;
1952                         else
1953                                 spare++;
1954                 }
1955         }
1956
1957         info.major_version = mddev->major_version;
1958         info.minor_version = mddev->minor_version;
1959         info.patch_version = MD_PATCHLEVEL_VERSION;
1960         info.ctime         = mddev->ctime;
1961         info.level         = mddev->level;
1962         info.size          = mddev->size;
1963         info.nr_disks      = nr;
1964         info.raid_disks    = mddev->raid_disks;
1965         info.md_minor      = mddev->md_minor;
1966         info.not_persistent= !mddev->persistent;
1967
1968         info.utime         = mddev->utime;
1969         info.state         = 0;
1970         if (mddev->in_sync)
1971                 info.state = (1<<MD_SB_CLEAN);
1972         info.active_disks  = active;
1973         info.working_disks = working;
1974         info.failed_disks  = failed;
1975         info.spare_disks   = spare;
1976
1977         info.layout        = mddev->layout;
1978         info.chunk_size    = mddev->chunk_size;
1979
1980         if (copy_to_user(arg, &info, sizeof(info)))
1981                 return -EFAULT;
1982
1983         return 0;
1984 }
1985
1986 static int get_disk_info(mddev_t * mddev, void __user * arg)
1987 {
1988         mdu_disk_info_t info;
1989         unsigned int nr;
1990         mdk_rdev_t *rdev;
1991
1992         if (copy_from_user(&info, arg, sizeof(info)))
1993                 return -EFAULT;
1994
1995         nr = info.number;
1996
1997         rdev = find_rdev_nr(mddev, nr);
1998         if (rdev) {
1999                 info.major = MAJOR(rdev->bdev->bd_dev);
2000                 info.minor = MINOR(rdev->bdev->bd_dev);
2001                 info.raid_disk = rdev->raid_disk;
2002                 info.state = 0;
2003                 if (rdev->faulty)
2004                         info.state |= (1<<MD_DISK_FAULTY);
2005                 else if (rdev->in_sync) {
2006                         info.state |= (1<<MD_DISK_ACTIVE);
2007                         info.state |= (1<<MD_DISK_SYNC);
2008                 }
2009         } else {
2010                 info.major = info.minor = 0;
2011                 info.raid_disk = -1;
2012                 info.state = (1<<MD_DISK_REMOVED);
2013         }
2014
2015         if (copy_to_user(arg, &info, sizeof(info)))
2016                 return -EFAULT;
2017
2018         return 0;
2019 }
2020
2021 static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
2022 {
2023         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
2024         mdk_rdev_t *rdev;
2025         dev_t dev = MKDEV(info->major,info->minor);
2026
2027         if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
2028                 return -EOVERFLOW;
2029
2030         if (!mddev->raid_disks) {
2031                 int err;
2032                 /* expecting a device which has a superblock */
2033                 rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
2034                 if (IS_ERR(rdev)) {
2035                         printk(KERN_WARNING
2036                                 "md: md_import_device returned %ld\n",
2037                                 PTR_ERR(rdev));
2038                         return PTR_ERR(rdev);
2039                 }
2040                 if (!list_empty(&mddev->disks)) {
2041                         mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
2042                                                         mdk_rdev_t, same_set);
2043                         int err = super_types[mddev->major_version]
2044                                 .load_super(rdev, rdev0, mddev->minor_version);
2045                         if (err < 0) {
2046                                 printk(KERN_WARNING
2047                                         "md: %s has different UUID to %s\n",
2048                                         bdevname(rdev->bdev,b),
2049                                         bdevname(rdev0->bdev,b2));
2050                                 export_rdev(rdev);
2051                                 return -EINVAL;
2052                         }
2053                 }
2054                 err = bind_rdev_to_array(rdev, mddev);
2055                 if (err)
2056                         export_rdev(rdev);
2057                 return err;
2058         }
2059
2060         /*
2061          * add_new_disk can be used once the array is assembled
2062          * to add "hot spares".  They must already have a superblock
2063          * written
2064          */
2065         if (mddev->pers) {
2066                 int err;
2067                 if (!mddev->pers->hot_add_disk) {
2068                         printk(KERN_WARNING
2069                                 "%s: personality does not support diskops!\n",
2070                                mdname(mddev));
2071                         return -EINVAL;
2072                 }
2073                 rdev = md_import_device(dev, mddev->major_version,
2074                                         mddev->minor_version);
2075                 if (IS_ERR(rdev)) {
2076                         printk(KERN_WARNING
2077                                 "md: md_import_device returned %ld\n",
2078                                 PTR_ERR(rdev));
2079                         return PTR_ERR(rdev);
2080                 }
2081                 rdev->in_sync = 0; /* just to be sure */
2082                 rdev->raid_disk = -1;
2083                 err = bind_rdev_to_array(rdev, mddev);
2084                 if (err)
2085                         export_rdev(rdev);
2086
2087                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2088                 if (mddev->thread)
2089                         md_wakeup_thread(mddev->thread);
2090                 return err;
2091         }
2092
2093         /* otherwise, add_new_disk is only allowed
2094          * for major_version==0 superblocks
2095          */
2096         if (mddev->major_version != 0) {
2097                 printk(KERN_WARNING "%s: ADD_NEW_DISK not supported\n",
2098                        mdname(mddev));
2099                 return -EINVAL;
2100         }
2101
2102         if (!(info->state & (1<<MD_DISK_FAULTY))) {
2103                 int err;
2104                 rdev = md_import_device (dev, -1, 0);
2105                 if (IS_ERR(rdev)) {
2106                         printk(KERN_WARNING
2107                                 "md: error, md_import_device() returned %ld\n",
2108                                 PTR_ERR(rdev));
2109                         return PTR_ERR(rdev);
2110                 }
2111                 rdev->desc_nr = info->number;
2112                 if (info->raid_disk < mddev->raid_disks)
2113                         rdev->raid_disk = info->raid_disk;
2114                 else
2115                         rdev->raid_disk = -1;
2116
2117                 rdev->faulty = 0;
2118                 if (rdev->raid_disk < mddev->raid_disks)
2119                         rdev->in_sync = (info->state & (1<<MD_DISK_SYNC));
2120                 else
2121                         rdev->in_sync = 0;
2122
2123                 err = bind_rdev_to_array(rdev, mddev);
2124                 if (err) {
2125                         export_rdev(rdev);
2126                         return err;
2127                 }
2128
2129                 if (!mddev->persistent) {
2130                         printk(KERN_INFO "md: nonpersistent superblock ...\n");
2131                         rdev->sb_offset = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
2132                 } else
2133                         rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
2134                 rdev->size = calc_dev_size(rdev, mddev->chunk_size);
2135
2136                 if (!mddev->size || (mddev->size > rdev->size))
2137                         mddev->size = rdev->size;
2138         }
2139
2140         return 0;
2141 }
2142
2143 static int hot_remove_disk(mddev_t * mddev, dev_t dev)
2144 {
2145         char b[BDEVNAME_SIZE];
2146         mdk_rdev_t *rdev;
2147
2148         if (!mddev->pers)
2149                 return -ENODEV;
2150
2151         rdev = find_rdev(mddev, dev);
2152         if (!rdev)
2153                 return -ENXIO;
2154
2155         if (rdev->raid_disk >= 0)
2156                 goto busy;
2157
2158         kick_rdev_from_array(rdev);
2159         md_update_sb(mddev);
2160
2161         return 0;
2162 busy:
2163         printk(KERN_WARNING "md: cannot remove active disk %s from %s ... \n",
2164                 bdevname(rdev->bdev,b), mdname(mddev));
2165         return -EBUSY;
2166 }
2167
2168 static int hot_add_disk(mddev_t * mddev, dev_t dev)
2169 {
2170         char b[BDEVNAME_SIZE];
2171         int err;
2172         unsigned int size;
2173         mdk_rdev_t *rdev;
2174
2175         if (!mddev->pers)
2176                 return -ENODEV;
2177
2178         if (mddev->major_version != 0) {
2179                 printk(KERN_WARNING "%s: HOT_ADD may only be used with"
2180                         " version-0 superblocks.\n",
2181                         mdname(mddev));
2182                 return -EINVAL;
2183         }
2184         if (!mddev->pers->hot_add_disk) {
2185                 printk(KERN_WARNING
2186                         "%s: personality does not support diskops!\n",
2187                         mdname(mddev));
2188                 return -EINVAL;
2189         }
2190
2191         rdev = md_import_device (dev, -1, 0);
2192         if (IS_ERR(rdev)) {
2193                 printk(KERN_WARNING
2194                         "md: error, md_import_device() returned %ld\n",
2195                         PTR_ERR(rdev));
2196                 return -EINVAL;
2197         }
2198
2199         if (mddev->persistent)
2200                 rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
2201         else
2202                 rdev->sb_offset =
2203                         rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
2204
2205         size = calc_dev_size(rdev, mddev->chunk_size);
2206         rdev->size = size;
2207
2208         if (size < mddev->size) {
2209                 printk(KERN_WARNING
2210                         "%s: disk size %llu blocks < array size %llu\n",
2211                         mdname(mddev), (unsigned long long)size,
2212                         (unsigned long long)mddev->size);
2213                 err = -ENOSPC;
2214                 goto abort_export;
2215         }
2216
2217         if (rdev->faulty) {
2218                 printk(KERN_WARNING
2219                         "md: can not hot-add faulty %s disk to %s!\n",
2220                         bdevname(rdev->bdev,b), mdname(mddev));
2221                 err = -EINVAL;
2222                 goto abort_export;
2223         }
2224         rdev->in_sync = 0;
2225         rdev->desc_nr = -1;
2226         bind_rdev_to_array(rdev, mddev);
2227
2228         /*
2229          * The rest should better be atomic, we can have disk failures
2230          * noticed in interrupt contexts ...
2231          */
2232
2233         if (rdev->desc_nr == mddev->max_disks) {
2234                 printk(KERN_WARNING "%s: can not hot-add to full array!\n",
2235                         mdname(mddev));
2236                 err = -EBUSY;
2237                 goto abort_unbind_export;
2238         }
2239
2240         rdev->raid_disk = -1;
2241
2242         md_update_sb(mddev);
2243
2244         /*
2245          * Kick recovery, maybe this spare has to be added to the
2246          * array immediately.
2247          */
2248         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2249         md_wakeup_thread(mddev->thread);
2250
2251         return 0;
2252
2253 abort_unbind_export:
2254         unbind_rdev_from_array(rdev);
2255
2256 abort_export:
2257         export_rdev(rdev);
2258         return err;
2259 }
2260
2261 /*
2262  * set_array_info is used two different ways
2263  * The original usage is when creating a new array.
2264  * In this usage, raid_disks is > 0 and it together with
2265  *  level, size, not_persistent,layout,chunksize determine the
2266  *  shape of the array.
2267  *  This will always create an array with a type-0.90.0 superblock.
2268  * The newer usage is when assembling an array.
2269  *  In this case raid_disks will be 0, and the major_version field is
2270  *  use to determine which style super-blocks are to be found on the devices.
2271  *  The minor and patch _version numbers are also kept incase the
2272  *  super_block handler wishes to interpret them.
2273  */
2274 static int set_array_info(mddev_t * mddev, mdu_array_info_t *info)
2275 {
2276
2277         if (info->raid_disks == 0) {
2278                 /* just setting version number for superblock loading */
2279                 if (info->major_version < 0 ||
2280                     info->major_version >= sizeof(super_types)/sizeof(super_types[0]) ||
2281                     super_types[info->major_version].name == NULL) {
2282                         /* maybe try to auto-load a module? */
2283                         printk(KERN_INFO
2284                                 "md: superblock version %d not known\n",
2285                                 info->major_version);
2286                         return -EINVAL;
2287                 }
2288                 mddev->major_version = info->major_version;
2289                 mddev->minor_version = info->minor_version;
2290                 mddev->patch_version = info->patch_version;
2291                 return 0;
2292         }
2293         mddev->major_version = MD_MAJOR_VERSION;
2294         mddev->minor_version = MD_MINOR_VERSION;
2295         mddev->patch_version = MD_PATCHLEVEL_VERSION;
2296         mddev->ctime         = get_seconds();
2297
2298         mddev->level         = info->level;
2299         mddev->size          = info->size;
2300         mddev->raid_disks    = info->raid_disks;
2301         /* don't set md_minor, it is determined by which /dev/md* was
2302          * openned
2303          */
2304         if (info->state & (1<<MD_SB_CLEAN))
2305                 mddev->recovery_cp = MaxSector;
2306         else
2307                 mddev->recovery_cp = 0;
2308         mddev->persistent    = ! info->not_persistent;
2309
2310         mddev->layout        = info->layout;
2311         mddev->chunk_size    = info->chunk_size;
2312
2313         mddev->max_disks     = MD_SB_DISKS;
2314
2315         mddev->sb_dirty      = 1;
2316
2317         /*
2318          * Generate a 128 bit UUID
2319          */
2320         get_random_bytes(mddev->uuid, 16);
2321
2322         return 0;
2323 }
2324
2325 /*
2326  * update_array_info is used to change the configuration of an
2327  * on-line array.
2328  * The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
2329  * fields in the info are checked against the array.
2330  * Any differences that cannot be handled will cause an error.
2331  * Normally, only one change can be managed at a time.
2332  */
2333 static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
2334 {
2335         int rv = 0;
2336         int cnt = 0;
2337
2338         if (mddev->major_version != info->major_version ||
2339             mddev->minor_version != info->minor_version ||
2340 /*          mddev->patch_version != info->patch_version || */
2341             mddev->ctime         != info->ctime         ||
2342             mddev->level         != info->level         ||
2343 /*          mddev->layout        != info->layout        || */
2344             !mddev->persistent   != info->not_persistent||
2345             mddev->chunk_size    != info->chunk_size    )
2346                 return -EINVAL;
2347         /* Check there is only one change */
2348         if (mddev->size != info->size) cnt++;
2349         if (mddev->raid_disks != info->raid_disks) cnt++;
2350         if (mddev->layout != info->layout) cnt++;
2351         if (cnt == 0) return 0;
2352         if (cnt > 1) return -EINVAL;
2353
2354         if (mddev->layout != info->layout) {
2355                 /* Change layout
2356                  * we don't need to do anything at the md level, the
2357                  * personality will take care of it all.
2358                  */
2359                 if (mddev->pers->reconfig == NULL)
2360                         return -EINVAL;
2361                 else
2362                         return mddev->pers->reconfig(mddev, info->layout, -1);
2363         }
2364         if (mddev->size != info->size) {
2365                 mdk_rdev_t * rdev;
2366                 struct list_head *tmp;
2367                 if (mddev->pers->resize == NULL)
2368                         return -EINVAL;
2369                 /* The "size" is the amount of each device that is used.
2370                  * This can only make sense for arrays with redundancy.
2371                  * linear and raid0 always use whatever space is available
2372                  * We can only consider changing the size if no resync
2373                  * or reconstruction is happening, and if the new size
2374                  * is acceptable. It must fit before the sb_offset or,
2375                  * if that is <data_offset, it must fit before the
2376                  * size of each device.
2377                  * If size is zero, we find the largest size that fits.
2378                  */
2379                 if (mddev->sync_thread)
2380                         return -EBUSY;
2381                 ITERATE_RDEV(mddev,rdev,tmp) {
2382                         sector_t avail;
2383                         int fit = (info->size == 0);
2384                         if (rdev->sb_offset > rdev->data_offset)
2385                                 avail = (rdev->sb_offset*2) - rdev->data_offset;
2386                         else
2387                                 avail = get_capacity(rdev->bdev->bd_disk)
2388                                         - rdev->data_offset;
2389                         if (fit && (info->size == 0 || info->size > avail/2))
2390                                 info->size = avail/2;
2391                         if (avail < ((sector_t)info->size << 1))
2392                                 return -ENOSPC;
2393                 }
2394                 rv = mddev->pers->resize(mddev, (sector_t)info->size *2);
2395                 if (!rv) {
2396                         struct block_device *bdev;
2397
2398                         bdev = bdget_disk(mddev->gendisk, 0);
2399                         if (bdev) {
2400                                 down(&bdev->bd_inode->i_sem);
2401                                 i_size_write(bdev->bd_inode, mddev->array_size << 10);
2402                                 up(&bdev->bd_inode->i_sem);
2403                                 bdput(bdev);
2404                         }
2405                 }
2406         }
2407         if (mddev->raid_disks    != info->raid_disks) {
2408                 /* change the number of raid disks */
2409                 if (mddev->pers->reshape == NULL)
2410                         return -EINVAL;
2411                 if (info->raid_disks <= 0 ||
2412                     info->raid_disks >= mddev->max_disks)
2413                         return -EINVAL;
2414                 if (mddev->sync_thread)
2415                         return -EBUSY;
2416                 rv = mddev->pers->reshape(mddev, info->raid_disks);
2417                 if (!rv) {
2418                         struct block_device *bdev;
2419
2420                         bdev = bdget_disk(mddev->gendisk, 0);
2421                         if (bdev) {
2422                                 down(&bdev->bd_inode->i_sem);
2423                                 i_size_write(bdev->bd_inode, mddev->array_size << 10);
2424                                 up(&bdev->bd_inode->i_sem);
2425                                 bdput(bdev);
2426                         }
2427                 }
2428         }
2429         md_update_sb(mddev);
2430         return rv;
2431 }
2432
2433 static int set_disk_faulty(mddev_t *mddev, dev_t dev)
2434 {
2435         mdk_rdev_t *rdev;
2436
2437         if (mddev->pers == NULL)
2438                 return -ENODEV;
2439
2440         rdev = find_rdev(mddev, dev);
2441         if (!rdev)
2442                 return -ENODEV;
2443
2444         md_error(mddev, rdev);
2445         return 0;
2446 }
2447
2448 static int md_ioctl(struct inode *inode, struct file *file,
2449                         unsigned int cmd, unsigned long arg)
2450 {
2451         int err = 0;
2452         void __user *argp = (void __user *)arg;
2453         struct hd_geometry __user *loc = argp;
2454         mddev_t *mddev = NULL;
2455
2456         if (!capable(CAP_SYS_ADMIN))
2457                 return -EACCES;
2458
2459         /*
2460          * Commands dealing with the RAID driver but not any
2461          * particular array:
2462          */
2463         switch (cmd)
2464         {
2465                 case RAID_VERSION:
2466                         err = get_version(argp);
2467                         goto done;
2468
2469                 case PRINT_RAID_DEBUG:
2470                         err = 0;
2471                         md_print_devices();
2472                         goto done;
2473
2474 #ifndef MODULE
2475                 case RAID_AUTORUN:
2476                         err = 0;
2477                         autostart_arrays(arg);
2478                         goto done;
2479 #endif
2480                 default:;
2481         }
2482
2483         /*
2484          * Commands creating/starting a new array:
2485          */
2486
2487         mddev = inode->i_bdev->bd_disk->private_data;
2488
2489         if (!mddev) {
2490                 BUG();
2491                 goto abort;
2492         }
2493
2494
2495         if (cmd == START_ARRAY) {
2496                 /* START_ARRAY doesn't need to lock the array as autostart_array
2497                  * does the locking, and it could even be a different array
2498                  */
2499                 static int cnt = 3;
2500                 if (cnt > 0 ) {
2501                         printk(KERN_WARNING
2502                                "md: %s(pid %d) used deprecated START_ARRAY ioctl. "
2503                                "This will not be supported beyond 2.6\n",
2504                                current->comm, current->pid);
2505                         cnt--;
2506                 }
2507                 err = autostart_array(new_decode_dev(arg));
2508                 if (err) {
2509                         printk(KERN_WARNING "md: autostart failed!\n");
2510                         goto abort;
2511                 }
2512                 goto done;
2513         }
2514
2515         err = mddev_lock(mddev);
2516         if (err) {
2517                 printk(KERN_INFO
2518                         "md: ioctl lock interrupted, reason %d, cmd %d\n",
2519                         err, cmd);
2520                 goto abort;
2521         }
2522
2523         switch (cmd)
2524         {
2525                 case SET_ARRAY_INFO:
2526                         {
2527                                 mdu_array_info_t info;
2528                                 if (!arg)
2529                                         memset(&info, 0, sizeof(info));
2530                                 else if (copy_from_user(&info, argp, sizeof(info))) {
2531                                         err = -EFAULT;
2532                                         goto abort_unlock;
2533                                 }
2534                                 if (mddev->pers) {
2535                                         err = update_array_info(mddev, &info);
2536                                         if (err) {
2537                                                 printk(KERN_WARNING "md: couldn't update"
2538                                                        " array info. %d\n", err);
2539                                                 goto abort_unlock;
2540                                         }
2541                                         goto done_unlock;
2542                                 }
2543                                 if (!list_empty(&mddev->disks)) {
2544                                         printk(KERN_WARNING
2545                                                "md: array %s already has disks!\n",
2546                                                mdname(mddev));
2547                                         err = -EBUSY;
2548                                         goto abort_unlock;
2549                                 }
2550                                 if (mddev->raid_disks) {
2551                                         printk(KERN_WARNING
2552                                                "md: array %s already initialised!\n",
2553                                                mdname(mddev));
2554                                         err = -EBUSY;
2555                                         goto abort_unlock;
2556                                 }
2557                                 err = set_array_info(mddev, &info);
2558                                 if (err) {
2559                                         printk(KERN_WARNING "md: couldn't set"
2560                                                " array info. %d\n", err);
2561                                         goto abort_unlock;
2562                                 }
2563                         }
2564                         goto done_unlock;
2565
2566                 default:;
2567         }
2568
2569         /*
2570          * Commands querying/configuring an existing array:
2571          */
2572         /* if we are initialised yet, only ADD_NEW_DISK or STOP_ARRAY is allowed */
2573         if (!mddev->raid_disks && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY && cmd != RUN_ARRAY) {
2574                 err = -ENODEV;
2575                 goto abort_unlock;
2576         }
2577
2578         /*
2579          * Commands even a read-only array can execute:
2580          */
2581         switch (cmd)
2582         {
2583                 case GET_ARRAY_INFO:
2584                         err = get_array_info(mddev, argp);
2585                         goto done_unlock;
2586
2587                 case GET_DISK_INFO:
2588                         err = get_disk_info(mddev, argp);
2589                         goto done_unlock;
2590
2591                 case RESTART_ARRAY_RW:
2592                         err = restart_array(mddev);
2593                         goto done_unlock;
2594
2595                 case STOP_ARRAY:
2596                         err = do_md_stop (mddev, 0);
2597                         goto done_unlock;
2598
2599                 case STOP_ARRAY_RO:
2600                         err = do_md_stop (mddev, 1);
2601                         goto done_unlock;
2602
2603         /*
2604          * We have a problem here : there is no easy way to give a CHS
2605          * virtual geometry. We currently pretend that we have a 2 heads
2606          * 4 sectors (with a BIG number of cylinders...). This drives
2607          * dosfs just mad... ;-)
2608          */
2609                 case HDIO_GETGEO:
2610                         if (!loc) {
2611                                 err = -EINVAL;
2612                                 goto abort_unlock;
2613                         }
2614                         err = put_user (2, (char __user *) &loc->heads);
2615                         if (err)
2616                                 goto abort_unlock;
2617                         err = put_user (4, (char __user *) &loc->sectors);
2618                         if (err)
2619                                 goto abort_unlock;
2620                         err = put_user(get_capacity(mddev->gendisk)/8,
2621                                         (short __user *) &loc->cylinders);
2622                         if (err)
2623                                 goto abort_unlock;
2624                         err = put_user (get_start_sect(inode->i_bdev),
2625                                                 (long __user *) &loc->start);
2626                         goto done_unlock;
2627         }
2628
2629         /*
2630          * The remaining ioctls are changing the state of the
2631          * superblock, so we do not allow read-only arrays
2632          * here:
2633          */
2634         if (mddev->ro) {
2635                 err = -EROFS;
2636                 goto abort_unlock;
2637         }
2638
2639         switch (cmd)
2640         {
2641                 case ADD_NEW_DISK:
2642                 {
2643                         mdu_disk_info_t info;
2644                         if (copy_from_user(&info, argp, sizeof(info)))
2645                                 err = -EFAULT;
2646                         else
2647                                 err = add_new_disk(mddev, &info);
2648                         goto done_unlock;
2649                 }
2650
2651                 case HOT_REMOVE_DISK:
2652                         err = hot_remove_disk(mddev, new_decode_dev(arg));
2653                         goto done_unlock;
2654
2655                 case HOT_ADD_DISK:
2656                         err = hot_add_disk(mddev, new_decode_dev(arg));
2657                         goto done_unlock;
2658
2659                 case SET_DISK_FAULTY:
2660                         err = set_disk_faulty(mddev, new_decode_dev(arg));
2661                         goto done_unlock;
2662
2663                 case RUN_ARRAY:
2664                         err = do_md_run (mddev);
2665                         goto done_unlock;
2666
2667                 default:
2668                         if (_IOC_TYPE(cmd) == MD_MAJOR)
2669                                 printk(KERN_WARNING "md: %s(pid %d) used"
2670                                         " obsolete MD ioctl, upgrade your"
2671                                         " software to use new ictls.\n",
2672                                         current->comm, current->pid);
2673                         err = -EINVAL;
2674                         goto abort_unlock;
2675         }
2676
2677 done_unlock:
2678 abort_unlock:
2679         mddev_unlock(mddev);
2680
2681         return err;
2682 done:
2683         if (err)
2684                 MD_BUG();
2685 abort:
2686         return err;
2687 }
2688
2689 static int md_open(struct inode *inode, struct file *file)
2690 {
2691         /*
2692          * Succeed if we can lock the mddev, which confirms that
2693          * it isn't being stopped right now.
2694          */
2695         mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
2696         int err;
2697
2698         if ((err = mddev_lock(mddev)))
2699                 goto out;
2700
2701         err = 0;
2702         mddev_get(mddev);
2703         mddev_unlock(mddev);
2704
2705         check_disk_change(inode->i_bdev);
2706  out:
2707         return err;
2708 }
2709
2710 static int md_release(struct inode *inode, struct file * file)
2711 {
2712         mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
2713
2714         if (!mddev)
2715                 BUG();
2716         mddev_put(mddev);
2717
2718         return 0;
2719 }
2720
2721 static int md_media_changed(struct gendisk *disk)
2722 {
2723         mddev_t *mddev = disk->private_data;
2724
2725         return mddev->changed;
2726 }
2727
2728 static int md_revalidate(struct gendisk *disk)
2729 {
2730         mddev_t *mddev = disk->private_data;
2731
2732         mddev->changed = 0;
2733         return 0;
2734 }
2735 static struct block_device_operations md_fops =
2736 {
2737         .owner          = THIS_MODULE,
2738         .open           = md_open,
2739         .release        = md_release,
2740         .ioctl          = md_ioctl,
2741         .media_changed  = md_media_changed,
2742         .revalidate_disk= md_revalidate,
2743 };
2744
2745 static int md_thread(void * arg)
2746 {
2747         mdk_thread_t *thread = arg;
2748
2749         lock_kernel();
2750
2751         /*
2752          * Detach thread
2753          */
2754
2755         daemonize(thread->name, mdname(thread->mddev));
2756
2757         current->exit_signal = SIGCHLD;
2758         allow_signal(SIGKILL);
2759         thread->tsk = current;
2760
2761         /*
2762          * md_thread is a 'system-thread', it's priority should be very
2763          * high. We avoid resource deadlocks individually in each
2764          * raid personality. (RAID5 does preallocation) We also use RR and
2765          * the very same RT priority as kswapd, thus we will never get
2766          * into a priority inversion deadlock.
2767          *
2768          * we definitely have to have equal or higher priority than
2769          * bdflush, otherwise bdflush will deadlock if there are too
2770          * many dirty RAID5 blocks.
2771          */
2772         unlock_kernel();
2773
2774         complete(thread->event);
2775         while (thread->run) {
2776                 void (*run)(mddev_t *);
2777
2778                 wait_event_interruptible(thread->wqueue,
2779                                          test_bit(THREAD_WAKEUP, &thread->flags));
2780                 if (current->flags & PF_FREEZE)
2781                         refrigerator(PF_FREEZE);
2782
2783                 clear_bit(THREAD_WAKEUP, &thread->flags);
2784
2785                 run = thread->run;
2786                 if (run)
2787                         run(thread->mddev);
2788
2789                 if (signal_pending(current))
2790                         flush_signals(current);
2791         }
2792         complete(thread->event);
2793         return 0;
2794 }
2795
2796 void md_wakeup_thread(mdk_thread_t *thread)
2797 {
2798         if (thread) {
2799                 dprintk("md: waking up MD thread %s.\n", thread->tsk->comm);
2800                 set_bit(THREAD_WAKEUP, &thread->flags);
2801                 wake_up(&thread->wqueue);
2802         }
2803 }
2804
2805 mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev,
2806                                  const char *name)
2807 {
2808         mdk_thread_t *thread;
2809         int ret;
2810         struct completion event;
2811
2812         thread = (mdk_thread_t *) kmalloc
2813                                 (sizeof(mdk_thread_t), GFP_KERNEL);
2814         if (!thread)
2815                 return NULL;
2816
2817         memset(thread, 0, sizeof(mdk_thread_t));
2818         init_waitqueue_head(&thread->wqueue);
2819
2820         init_completion(&event);
2821         thread->event = &event;
2822         thread->run = run;
2823         thread->mddev = mddev;
2824         thread->name = name;
2825         ret = kernel_thread(md_thread, thread, 0);
2826         if (ret < 0) {
2827                 kfree(thread);
2828                 return NULL;
2829         }
2830         wait_for_completion(&event);
2831         return thread;
2832 }
2833
2834 void md_unregister_thread(mdk_thread_t *thread)
2835 {
2836         struct completion event;
2837
2838         init_completion(&event);
2839
2840         thread->event = &event;
2841
2842         /* As soon as ->run is set to NULL, the task could disappear,
2843          * so we need to hold tasklist_lock until we have sent the signal
2844          */
2845         dprintk("interrupting MD-thread pid %d\n", thread->tsk->pid);
2846         read_lock(&tasklist_lock);
2847         thread->run = NULL;
2848         send_sig(SIGKILL, thread->tsk, 1);
2849         read_unlock(&tasklist_lock);
2850         wait_for_completion(&event);
2851         kfree(thread);
2852 }
2853
2854 void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
2855 {
2856         if (!mddev) {
2857                 MD_BUG();
2858                 return;
2859         }
2860
2861         if (!rdev || rdev->faulty)
2862                 return;
2863
2864         dprintk("md_error dev:%s, rdev:(%d:%d), (caller: %p,%p,%p,%p).\n",
2865                 mdname(mddev),
2866                 MAJOR(rdev->bdev->bd_dev), MINOR(rdev->bdev->bd_dev),
2867                 __builtin_return_address(0),__builtin_return_address(1),
2868                 __builtin_return_address(2),__builtin_return_address(3));
2869
2870         if (!mddev->pers->error_handler)
2871                 return;
2872         mddev->pers->error_handler(mddev,rdev);
2873         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2874         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2875         md_wakeup_thread(mddev->thread);
2876 }
2877
2878 /* seq_file implementation /proc/mdstat */
2879
2880 static void status_unused(struct seq_file *seq)
2881 {
2882         int i = 0;
2883         mdk_rdev_t *rdev;
2884         struct list_head *tmp;
2885
2886         seq_printf(seq, "unused devices: ");
2887
2888         ITERATE_RDEV_PENDING(rdev,tmp) {
2889                 char b[BDEVNAME_SIZE];
2890                 i++;
2891                 seq_printf(seq, "%s ",
2892                               bdevname(rdev->bdev,b));
2893         }
2894         if (!i)
2895                 seq_printf(seq, "<none>");
2896
2897         seq_printf(seq, "\n");
2898 }
2899
2900
2901 static void status_resync(struct seq_file *seq, mddev_t * mddev)
2902 {
2903         unsigned long max_blocks, resync, res, dt, db, rt;
2904
2905         resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active))/2;
2906
2907         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
2908                 max_blocks = mddev->resync_max_sectors >> 1;
2909         else
2910                 max_blocks = mddev->size;
2911
2912         /*
2913          * Should not happen.
2914          */
2915         if (!max_blocks) {
2916                 MD_BUG();
2917                 return;
2918         }
2919         res = (resync/1024)*1000/(max_blocks/1024 + 1);
2920         {
2921                 int i, x = res/50, y = 20-x;
2922                 seq_printf(seq, "[");
2923                 for (i = 0; i < x; i++)
2924                         seq_printf(seq, "=");
2925                 seq_printf(seq, ">");
2926                 for (i = 0; i < y; i++)
2927                         seq_printf(seq, ".");
2928                 seq_printf(seq, "] ");
2929         }
2930         seq_printf(seq, " %s =%3lu.%lu%% (%lu/%lu)",
2931                       (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
2932                        "resync" : "recovery"),
2933                       res/10, res % 10, resync, max_blocks);
2934
2935         /*
2936          * We do not want to overflow, so the order of operands and
2937          * the * 100 / 100 trick are important. We do a +1 to be
2938          * safe against division by zero. We only estimate anyway.
2939          *
2940          * dt: time from mark until now
2941          * db: blocks written from mark until now
2942          * rt: remaining time
2943          */
2944         dt = ((jiffies - mddev->resync_mark) / HZ);
2945         if (!dt) dt++;
2946         db = resync - (mddev->resync_mark_cnt/2);
2947         rt = (dt * ((max_blocks-resync) / (db/100+1)))/100;
2948
2949         seq_printf(seq, " finish=%lu.%lumin", rt / 60, (rt % 60)/6);
2950
2951         seq_printf(seq, " speed=%ldK/sec", db/dt);
2952 }
2953
2954 static void *md_seq_start(struct seq_file *seq, loff_t *pos)
2955 {
2956         struct list_head *tmp;
2957         loff_t l = *pos;
2958         mddev_t *mddev;
2959
2960         if (l >= 0x10000)
2961                 return NULL;
2962         if (!l--)
2963                 /* header */
2964                 return (void*)1;
2965
2966         spin_lock(&all_mddevs_lock);
2967         list_for_each(tmp,&all_mddevs)
2968                 if (!l--) {
2969                         mddev = list_entry(tmp, mddev_t, all_mddevs);
2970                         mddev_get(mddev);
2971                         spin_unlock(&all_mddevs_lock);
2972                         return mddev;
2973                 }
2974         spin_unlock(&all_mddevs_lock);
2975         if (!l--)
2976                 return (void*)2;/* tail */
2977         return NULL;
2978 }
2979
2980 static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2981 {
2982         struct list_head *tmp;
2983         mddev_t *next_mddev, *mddev = v;
2984
2985         ++*pos;
2986         if (v == (void*)2)
2987                 return NULL;
2988
2989         spin_lock(&all_mddevs_lock);
2990         if (v == (void*)1)
2991                 tmp = all_mddevs.next;
2992         else
2993                 tmp = mddev->all_mddevs.next;
2994         if (tmp != &all_mddevs)
2995                 next_mddev = mddev_get(list_entry(tmp,mddev_t,all_mddevs));
2996         else {
2997                 next_mddev = (void*)2;
2998                 *pos = 0x10000;
2999         }
3000         spin_unlock(&all_mddevs_lock);
3001
3002         if (v != (void*)1)
3003                 mddev_put(mddev);
3004         return next_mddev;
3005
3006 }
3007
3008 static void md_seq_stop(struct seq_file *seq, void *v)
3009 {
3010         mddev_t *mddev = v;
3011
3012         if (mddev && v != (void*)1 && v != (void*)2)
3013                 mddev_put(mddev);
3014 }
3015
3016 static int md_seq_show(struct seq_file *seq, void *v)
3017 {
3018         mddev_t *mddev = v;
3019         sector_t size;
3020         struct list_head *tmp2;
3021         mdk_rdev_t *rdev;
3022         int i;
3023
3024         if (v == (void*)1) {
3025                 seq_printf(seq, "Personalities : ");
3026                 spin_lock(&pers_lock);
3027                 for (i = 0; i < MAX_PERSONALITY; i++)
3028                         if (pers[i])
3029                                 seq_printf(seq, "[%s] ", pers[i]->name);
3030
3031                 spin_unlock(&pers_lock);
3032                 seq_printf(seq, "\n");
3033                 return 0;
3034         }
3035         if (v == (void*)2) {
3036                 status_unused(seq);
3037                 return 0;
3038         }
3039
3040         if (mddev_lock(mddev)!=0)
3041                 return -EINTR;
3042         if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
3043                 seq_printf(seq, "%s : %sactive", mdname(mddev),
3044                                                 mddev->pers ? "" : "in");
3045                 if (mddev->pers) {
3046                         if (mddev->ro)
3047                                 seq_printf(seq, " (read-only)");
3048                         seq_printf(seq, " %s", mddev->pers->name);
3049                 }
3050
3051                 size = 0;
3052                 ITERATE_RDEV(mddev,rdev,tmp2) {
3053                         char b[BDEVNAME_SIZE];
3054                         seq_printf(seq, " %s[%d]",
3055                                 bdevname(rdev->bdev,b), rdev->desc_nr);
3056                         if (rdev->faulty) {
3057                                 seq_printf(seq, "(F)");
3058                                 continue;
3059                         }
3060                         size += rdev->size;
3061                 }
3062
3063                 if (!list_empty(&mddev->disks)) {
3064                         if (mddev->pers)
3065                                 seq_printf(seq, "\n      %llu blocks",
3066                                         (unsigned long long)mddev->array_size);
3067                         else
3068                                 seq_printf(seq, "\n      %llu blocks",
3069                                         (unsigned long long)size);
3070                 }
3071
3072                 if (mddev->pers) {
3073                         mddev->pers->status (seq, mddev);
3074                         seq_printf(seq, "\n      ");
3075                         if (mddev->curr_resync > 2)
3076                                 status_resync (seq, mddev);
3077                         else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
3078                                 seq_printf(seq, "       resync=DELAYED");
3079                 }
3080
3081                 seq_printf(seq, "\n");
3082         }
3083         mddev_unlock(mddev);
3084
3085         return 0;
3086 }
3087
3088 static struct seq_operations md_seq_ops = {
3089         .start  = md_seq_start,
3090         .next   = md_seq_next,
3091         .stop   = md_seq_stop,
3092         .show   = md_seq_show,
3093 };
3094
3095 static int md_seq_open(struct inode *inode, struct file *file)
3096 {
3097         int error;
3098
3099         error = seq_open(file, &md_seq_ops);
3100         return error;
3101 }
3102
3103 static struct file_operations md_seq_fops = {
3104         .open           = md_seq_open,
3105         .read           = seq_read,
3106         .llseek         = seq_lseek,
3107         .release        = seq_release,
3108 };
3109
3110 int register_md_personality(int pnum, mdk_personality_t *p)
3111 {
3112         if (pnum >= MAX_PERSONALITY) {
3113                 printk(KERN_ERR
3114                        "md: tried to install personality %s as nr %d, but max is %lu\n",
3115                        p->name, pnum, MAX_PERSONALITY-1);
3116                 return -EINVAL;
3117         }
3118
3119         spin_lock(&pers_lock);
3120         if (pers[pnum]) {
3121                 spin_unlock(&pers_lock);
3122                 return -EBUSY;
3123         }
3124
3125         pers[pnum] = p;
3126         printk(KERN_INFO "md: %s personality registered as nr %d\n", p->name, pnum);
3127         spin_unlock(&pers_lock);
3128         return 0;
3129 }
3130
3131 int unregister_md_personality(int pnum)
3132 {
3133         if (pnum >= MAX_PERSONALITY)
3134                 return -EINVAL;
3135
3136         printk(KERN_INFO "md: %s personality unregistered\n", pers[pnum]->name);
3137         spin_lock(&pers_lock);
3138         pers[pnum] = NULL;
3139         spin_unlock(&pers_lock);
3140         return 0;
3141 }
3142
3143 static int is_mddev_idle(mddev_t *mddev)
3144 {
3145         mdk_rdev_t * rdev;
3146         struct list_head *tmp;
3147         int idle;
3148         unsigned long curr_events;
3149
3150         idle = 1;
3151         ITERATE_RDEV(mddev,rdev,tmp) {
3152                 struct gendisk *disk = rdev->bdev->bd_contains->bd_disk;
3153                 curr_events = disk_stat_read(disk, read_sectors) +
3154                                 disk_stat_read(disk, write_sectors) -
3155                                 atomic_read(&disk->sync_io);
3156                 /* Allow some slack between valud of curr_events and last_events,
3157                  * as there are some uninteresting races.
3158                  * Note: the following is an unsigned comparison.
3159                  */
3160                 if ((curr_events - rdev->last_events + 32) > 64) {
3161                         rdev->last_events = curr_events;
3162                         idle = 0;
3163                 }
3164         }
3165         return idle;
3166 }
3167
3168 void md_done_sync(mddev_t *mddev, int blocks, int ok)
3169 {
3170         /* another "blocks" (512byte) blocks have been synced */
3171         atomic_sub(blocks, &mddev->recovery_active);
3172         wake_up(&mddev->recovery_wait);
3173         if (!ok) {
3174                 set_bit(MD_RECOVERY_ERR, &mddev->recovery);
3175                 md_wakeup_thread(mddev->thread);
3176                 // stop recovery, signal do_sync ....
3177         }
3178 }
3179
3180
3181 void md_write_start(mddev_t *mddev)
3182 {
3183         if (!atomic_read(&mddev->writes_pending)) {
3184                 mddev_lock_uninterruptible(mddev);
3185                 if (mddev->in_sync) {
3186                         mddev->in_sync = 0;
3187                         del_timer(&mddev->safemode_timer);
3188                         md_update_sb(mddev);
3189                 }
3190                 atomic_inc(&mddev->writes_pending);
3191                 mddev_unlock(mddev);
3192         } else
3193                 atomic_inc(&mddev->writes_pending);
3194 }
3195
3196 void md_write_end(mddev_t *mddev)
3197 {
3198         if (atomic_dec_and_test(&mddev->writes_pending)) {
3199                 if (mddev->safemode == 2)
3200                         md_wakeup_thread(mddev->thread);
3201                 else
3202                         mod_timer(&mddev->safemode_timer, jiffies + mddev->safemode_delay);
3203         }
3204 }
3205
3206 static inline void md_enter_safemode(mddev_t *mddev)
3207 {
3208         if (!mddev->safemode) return;
3209         if (mddev->safemode == 2 &&
3210             (atomic_read(&mddev->writes_pending) || mddev->in_sync ||
3211                     mddev->recovery_cp != MaxSector))
3212                 return; /* avoid the lock */
3213         mddev_lock_uninterruptible(mddev);
3214         if (mddev->safemode && !atomic_read(&mddev->writes_pending) &&
3215             !mddev->in_sync && mddev->recovery_cp == MaxSector) {
3216                 mddev->in_sync = 1;
3217                 md_update_sb(mddev);
3218         }
3219         mddev_unlock(mddev);
3220
3221         if (mddev->safemode == 1)
3222                 mddev->safemode = 0;
3223 }
3224
3225 void md_handle_safemode(mddev_t *mddev)
3226 {
3227         if (signal_pending(current)) {
3228                 printk(KERN_INFO "md: %s in immediate safe mode\n",
3229                         mdname(mddev));
3230                 mddev->safemode = 2;
3231                 flush_signals(current);
3232         }
3233         md_enter_safemode(mddev);
3234 }
3235
3236
3237 static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
3238
3239 #define SYNC_MARKS      10
3240 #define SYNC_MARK_STEP  (3*HZ)
3241 static void md_do_sync(mddev_t *mddev)
3242 {
3243         mddev_t *mddev2;
3244         unsigned int currspeed = 0,
3245                  window;
3246         sector_t max_sectors,j;
3247         unsigned long mark[SYNC_MARKS];
3248         sector_t mark_cnt[SYNC_MARKS];
3249         int last_mark,m;
3250         struct list_head *tmp;
3251         sector_t last_check;
3252
3253         /* just incase thread restarts... */
3254         if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
3255                 return;
3256
3257         /* we overload curr_resync somewhat here.
3258          * 0 == not engaged in resync at all
3259          * 2 == checking that there is no conflict with another sync
3260          * 1 == like 2, but have yielded to allow conflicting resync to
3261          *              commense
3262          * other == active in resync - this many blocks
3263          *
3264          * Before starting a resync we must have set curr_resync to
3265          * 2, and then checked that every "conflicting" array has curr_resync
3266          * less than ours.  When we find one that is the same or higher
3267          * we wait on resync_wait.  To avoid deadlock, we reduce curr_resync
3268          * to 1 if we choose to yield (based arbitrarily on address of mddev structure).
3269          * This will mean we have to start checking from the beginning again.
3270          *
3271          */
3272
3273         do {
3274                 mddev->curr_resync = 2;
3275
3276         try_again:
3277                 if (signal_pending(current)) {
3278                         flush_signals(current);
3279                         goto skip;
3280                 }
3281                 ITERATE_MDDEV(mddev2,tmp) {
3282                         printk(".");
3283                         if (mddev2 == mddev)
3284                                 continue;
3285                         if (mddev2->curr_resync &&
3286                             match_mddev_units(mddev,mddev2)) {
3287                                 DEFINE_WAIT(wq);
3288                                 if (mddev < mddev2 && mddev->curr_resync == 2) {
3289                                         /* arbitrarily yield */
3290                                         mddev->curr_resync = 1;
3291                                         wake_up(&resync_wait);
3292                                 }
3293                                 if (mddev > mddev2 && mddev->curr_resync == 1)
3294                                         /* no need to wait here, we can wait the next
3295                                          * time 'round when curr_resync == 2
3296                                          */
3297                                         continue;
3298                                 prepare_to_wait(&resync_wait, &wq, TASK_INTERRUPTIBLE);
3299                                 if (!signal_pending(current)
3300                                     && mddev2->curr_resync >= mddev->curr_resync) {
3301                                         printk(KERN_INFO "md: delaying resync of %s"
3302                                                " until %s has finished resync (they"
3303                                                " share one or more physical units)\n",
3304                                                mdname(mddev), mdname(mddev2));
3305                                         mddev_put(mddev2);
3306                                         schedule();
3307                                         finish_wait(&resync_wait, &wq);
3308                                         goto try_again;
3309                                 }
3310                                 finish_wait(&resync_wait, &wq);
3311                         }
3312                 }
3313         } while (mddev->curr_resync < 2);
3314
3315         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
3316                 /* resync follows the size requested by the personality,
3317                  * which default to physical size, but can be virtual size
3318                  */
3319                 max_sectors = mddev->resync_max_sectors;
3320         else
3321                 /* recovery follows the physical size of devices */
3322                 max_sectors = mddev->size << 1;
3323
3324         printk(KERN_INFO "md: syncing RAID array %s\n", mdname(mddev));
3325         printk(KERN_INFO "md: minimum _guaranteed_ reconstruction speed:"
3326                 " %d KB/sec/disc.\n", sysctl_speed_limit_min);
3327         printk(KERN_INFO "md: using maximum available idle IO bandwith "
3328                "(but not more than %d KB/sec) for reconstruction.\n",
3329                sysctl_speed_limit_max);
3330
3331         is_mddev_idle(mddev); /* this also initializes IO event counters */
3332         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
3333                 j = mddev->recovery_cp;
3334         else
3335                 j = 0;
3336         for (m = 0; m < SYNC_MARKS; m++) {
3337                 mark[m] = jiffies;
3338                 mark_cnt[m] = j;
3339         }
3340         last_mark = 0;
3341         mddev->resync_mark = mark[last_mark];
3342         mddev->resync_mark_cnt = mark_cnt[last_mark];
3343
3344         /*
3345          * Tune reconstruction:
3346          */
3347         window = 32*(PAGE_SIZE/512);
3348         printk(KERN_INFO "md: using %dk window, over a total of %llu blocks.\n",
3349                 window/2,(unsigned long long) max_sectors/2);
3350
3351         atomic_set(&mddev->recovery_active, 0);
3352         init_waitqueue_head(&mddev->recovery_wait);
3353         last_check = 0;
3354
3355         if (j>2) {
3356                 printk(KERN_INFO
3357                         "md: resuming recovery of %s from checkpoint.\n",
3358                         mdname(mddev));
3359                 mddev->curr_resync = j;
3360         }
3361
3362         while (j < max_sectors) {
3363                 int sectors;
3364
3365                 sectors = mddev->pers->sync_request(mddev, j, currspeed < sysctl_speed_limit_min);
3366                 if (sectors < 0) {
3367                         set_bit(MD_RECOVERY_ERR, &mddev->recovery);
3368                         goto out;
3369                 }
3370                 atomic_add(sectors, &mddev->recovery_active);
3371                 j += sectors;
3372                 if (j>1) mddev->curr_resync = j;
3373
3374                 if (last_check + window > j || j == max_sectors)
3375                         continue;
3376
3377                 last_check = j;
3378
3379                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery) ||
3380                     test_bit(MD_RECOVERY_ERR, &mddev->recovery))
3381                         break;
3382
3383         repeat:
3384                 if (time_after_eq(jiffies, mark[last_mark] + SYNC_MARK_STEP )) {
3385                         /* step marks */
3386                         int next = (last_mark+1) % SYNC_MARKS;
3387
3388                         mddev->resync_mark = mark[next];
3389                         mddev->resync_mark_cnt = mark_cnt[next];
3390                         mark[next] = jiffies;
3391                         mark_cnt[next] = j - atomic_read(&mddev->recovery_active);
3392                         last_mark = next;
3393                 }
3394
3395
3396                 if (signal_pending(current)) {
3397                         /*
3398                          * got a signal, exit.
3399                          */
3400                         printk(KERN_INFO
3401                                 "md: md_do_sync() got signal ... exiting\n");
3402                         flush_signals(current);
3403                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3404                         goto out;
3405                 }
3406
3407                 /*
3408                  * this loop exits only if either when we are slower than
3409                  * the 'hard' speed limit, or the system was IO-idle for
3410                  * a jiffy.
3411                  * the system might be non-idle CPU-wise, but we only care
3412                  * about not overloading the IO subsystem. (things like an
3413                  * e2fsck being done on the RAID array should execute fast)
3414                  */
3415                 mddev->queue->unplug_fn(mddev->queue);
3416                 cond_resched();
3417
3418                 currspeed = ((unsigned long)(j-mddev->resync_mark_cnt))/2/((jiffies-mddev->resync_mark)/HZ +1) +1;
3419
3420                 if (currspeed > sysctl_speed_limit_min) {
3421                         if ((currspeed > sysctl_speed_limit_max) ||
3422                                         !is_mddev_idle(mddev)) {
3423                                 msleep_interruptible(250);
3424                                 goto repeat;
3425                         }
3426                 }
3427         }
3428         printk(KERN_INFO "md: %s: sync done.\n",mdname(mddev));
3429         /*
3430          * this also signals 'finished resyncing' to md_stop
3431          */
3432  out:
3433         mddev->queue->unplug_fn(mddev->queue);
3434
3435         wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
3436
3437         /* tell personality that we are finished */
3438         mddev->pers->sync_request(mddev, max_sectors, 1);
3439
3440         if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
3441             mddev->curr_resync > 2 &&
3442             mddev->curr_resync >= mddev->recovery_cp) {
3443                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
3444                         printk(KERN_INFO
3445                                 "md: checkpointing recovery of %s.\n",
3446                                 mdname(mddev));
3447                         mddev->recovery_cp = mddev->curr_resync;
3448                 } else
3449                         mddev->recovery_cp = MaxSector;
3450         }
3451
3452         md_enter_safemode(mddev);
3453  skip:
3454         mddev->curr_resync = 0;
3455         wake_up(&resync_wait);
3456         set_bit(MD_RECOVERY_DONE, &mddev->recovery);
3457         md_wakeup_thread(mddev->thread);
3458 }
3459
3460
3461 /*
3462  * This routine is regularly called by all per-raid-array threads to
3463  * deal with generic issues like resync and super-block update.
3464  * Raid personalities that don't have a thread (linear/raid0) do not
3465  * need this as they never do any recovery or update the superblock.
3466  *
3467  * It does not do any resync itself, but rather "forks" off other threads
3468  * to do that as needed.
3469  * When it is determined that resync is needed, we set MD_RECOVERY_RUNNING in
3470  * "->recovery" and create a thread at ->sync_thread.
3471  * When the thread finishes it sets MD_RECOVERY_DONE (and might set MD_RECOVERY_ERR)
3472  * and wakeups up this thread which will reap the thread and finish up.
3473  * This thread also removes any faulty devices (with nr_pending == 0).
3474  *
3475  * The overall approach is:
3476  *  1/ if the superblock needs updating, update it.
3477  *  2/ If a recovery thread is running, don't do anything else.
3478  *  3/ If recovery has finished, clean up, possibly marking spares active.
3479  *  4/ If there are any faulty devices, remove them.
3480  *  5/ If array is degraded, try to add spares devices
3481  *  6/ If array has spares or is not in-sync, start a resync thread.
3482  */
3483 void md_check_recovery(mddev_t *mddev)
3484 {
3485         mdk_rdev_t *rdev;
3486         struct list_head *rtmp;
3487
3488
3489         dprintk(KERN_INFO "md: recovery thread got woken up ...\n");
3490
3491         if (mddev->ro)
3492                 return;
3493         if ( ! (
3494                 mddev->sb_dirty ||
3495                 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
3496                 test_bit(MD_RECOVERY_DONE, &mddev->recovery)
3497                 ))
3498                 return;
3499         if (mddev_trylock(mddev)==0) {
3500                 int spares =0;
3501                 if (mddev->sb_dirty)
3502                         md_update_sb(mddev);
3503                 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
3504                     !test_bit(MD_RECOVERY_DONE, &mddev->recovery)) {
3505                         /* resync/recovery still happening */
3506                         clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3507                         goto unlock;
3508                 }
3509                 if (mddev->sync_thread) {
3510                         /* resync has finished, collect result */
3511                         md_unregister_thread(mddev->sync_thread);
3512                         mddev->sync_thread = NULL;
3513                         if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
3514                             !test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
3515                                 /* success...*/
3516                                 /* activate any spares */
3517                                 mddev->pers->spare_active(mddev);
3518                         }
3519                         md_update_sb(mddev);
3520                         mddev->recovery = 0;
3521                         /* flag recovery needed just to double check */
3522                         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3523                         goto unlock;
3524                 }
3525                 if (mddev->recovery)
3526                         /* probably just the RECOVERY_NEEDED flag */
3527                         mddev->recovery = 0;
3528
3529                 /* no recovery is running.
3530                  * remove any failed drives, then
3531                  * add spares if possible.
3532                  * Spare are also removed and re-added, to allow
3533                  * the personality to fail the re-add.
3534                  */
3535                 ITERATE_RDEV(mddev,rdev,rtmp)
3536                         if (rdev->raid_disk >= 0 &&
3537                             (rdev->faulty || ! rdev->in_sync) &&
3538                             atomic_read(&rdev->nr_pending)==0) {
3539                                 if (mddev->pers->hot_remove_disk(mddev, rdev->raid_disk)==0)
3540                                         rdev->raid_disk = -1;
3541                         }
3542
3543                 if (mddev->degraded) {
3544                         ITERATE_RDEV(mddev,rdev,rtmp)
3545                                 if (rdev->raid_disk < 0
3546                                     && !rdev->faulty) {
3547                                         if (mddev->pers->hot_add_disk(mddev,rdev))
3548                                                 spares++;
3549                                         else
3550                                                 break;
3551                                 }
3552                 }
3553
3554                 if (!spares && (mddev->recovery_cp == MaxSector )) {
3555                         /* nothing we can do ... */
3556                         goto unlock;
3557                 }
3558                 if (mddev->pers->sync_request) {
3559                         set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
3560                         if (!spares)
3561                                 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3562                         mddev->sync_thread = md_register_thread(md_do_sync,
3563                                                                 mddev,
3564                                                                 "%s_resync");
3565                         if (!mddev->sync_thread) {
3566                                 printk(KERN_ERR "%s: could not start resync"
3567                                         " thread...\n",
3568                                         mdname(mddev));
3569                                 /* leave the spares where they are, it shouldn't hurt */
3570                                 mddev->recovery = 0;
3571                         } else {
3572                                 md_wakeup_thread(mddev->sync_thread);
3573                         }
3574                 }
3575         unlock:
3576                 mddev_unlock(mddev);
3577         }
3578 }
3579
3580 static int md_notify_reboot(struct notifier_block *this,
3581                             unsigned long code, void *x)
3582 {
3583         struct list_head *tmp;
3584         mddev_t *mddev;
3585
3586         if ((code == SYS_DOWN) || (code == SYS_HALT) || (code == SYS_POWER_OFF)) {
3587
3588                 printk(KERN_INFO "md: stopping all md devices.\n");
3589
3590                 ITERATE_MDDEV(mddev,tmp)
3591                         if (mddev_trylock(mddev)==0)
3592                                 do_md_stop (mddev, 1);
3593                 /*
3594                  * certain more exotic SCSI devices are known to be
3595                  * volatile wrt too early system reboots. While the
3596                  * right place to handle this issue is the given
3597                  * driver, we do want to have a safe RAID driver ...
3598                  */
3599                 mdelay(1000*1);
3600         }
3601         return NOTIFY_DONE;
3602 }
3603
3604 static struct notifier_block md_notifier = {
3605         .notifier_call  = md_notify_reboot,
3606         .next           = NULL,
3607         .priority       = INT_MAX, /* before any real devices */
3608 };
3609
3610 static void md_geninit(void)
3611 {
3612         struct proc_dir_entry *p;
3613
3614         dprintk("md: sizeof(mdp_super_t) = %d\n", (int)sizeof(mdp_super_t));
3615
3616         p = create_proc_entry("mdstat", S_IRUGO, NULL);
3617         if (p)
3618                 p->proc_fops = &md_seq_fops;
3619 }
3620
3621 static int __init md_init(void)
3622 {
3623         int minor;
3624
3625         printk(KERN_INFO "md: md driver %d.%d.%d MAX_MD_DEVS=%d,"
3626                         " MD_SB_DISKS=%d\n",
3627                         MD_MAJOR_VERSION, MD_MINOR_VERSION,
3628                         MD_PATCHLEVEL_VERSION, MAX_MD_DEVS, MD_SB_DISKS);
3629
3630         if (register_blkdev(MAJOR_NR, "md"))
3631                 return -1;
3632         if ((mdp_major=register_blkdev(0, "mdp"))<=0) {
3633                 unregister_blkdev(MAJOR_NR, "md");
3634                 return -1;
3635         }
3636         devfs_mk_dir("md");
3637         blk_register_region(MKDEV(MAJOR_NR, 0), MAX_MD_DEVS, THIS_MODULE,
3638                                 md_probe, NULL, NULL);
3639         blk_register_region(MKDEV(mdp_major, 0), MAX_MD_DEVS<<MdpMinorShift, THIS_MODULE,
3640                             md_probe, NULL, NULL);
3641
3642         for (minor=0; minor < MAX_MD_DEVS; ++minor)
3643                 devfs_mk_bdev(MKDEV(MAJOR_NR, minor),
3644                                 S_IFBLK|S_IRUSR|S_IWUSR,
3645                                 "md/%d", minor);
3646
3647         for (minor=0; minor < MAX_MD_DEVS; ++minor)
3648                 devfs_mk_bdev(MKDEV(mdp_major, minor<<MdpMinorShift),
3649                               S_IFBLK|S_IRUSR|S_IWUSR,
3650                               "md/mdp%d", minor);
3651
3652
3653         register_reboot_notifier(&md_notifier);
3654         raid_table_header = register_sysctl_table(raid_root_table, 1);
3655
3656         md_geninit();
3657         return (0);
3658 }
3659
3660
3661 #ifndef MODULE
3662
3663 /*
3664  * Searches all registered partitions for autorun RAID arrays
3665  * at boot time.
3666  */
3667 static dev_t detected_devices[128];
3668 static int dev_cnt;
3669
3670 void md_autodetect_dev(dev_t dev)
3671 {
3672         if (dev_cnt >= 0 && dev_cnt < 127)
3673                 detected_devices[dev_cnt++] = dev;
3674 }
3675
3676
3677 static void autostart_arrays(int part)
3678 {
3679         mdk_rdev_t *rdev;
3680         int i;
3681
3682         printk(KERN_INFO "md: Autodetecting RAID arrays.\n");
3683
3684         for (i = 0; i < dev_cnt; i++) {
3685                 dev_t dev = detected_devices[i];
3686
3687                 rdev = md_import_device(dev,0, 0);
3688                 if (IS_ERR(rdev))
3689                         continue;
3690
3691                 if (rdev->faulty) {
3692                         MD_BUG();
3693                         continue;
3694                 }
3695                 list_add(&rdev->same_set, &pending_raid_disks);
3696         }
3697         dev_cnt = 0;
3698
3699         autorun_devices(part);
3700 }
3701
3702 #endif
3703
3704 static __exit void md_exit(void)
3705 {
3706         mddev_t *mddev;
3707         struct list_head *tmp;
3708         int i;
3709         blk_unregister_region(MKDEV(MAJOR_NR,0), MAX_MD_DEVS);
3710         blk_unregister_region(MKDEV(mdp_major,0), MAX_MD_DEVS << MdpMinorShift);
3711         for (i=0; i < MAX_MD_DEVS; i++)
3712                 devfs_remove("md/%d", i);
3713         for (i=0; i < MAX_MD_DEVS; i++)
3714                 devfs_remove("md/d%d", i);
3715
3716         devfs_remove("md");
3717
3718         unregister_blkdev(MAJOR_NR,"md");
3719         unregister_blkdev(mdp_major, "mdp");
3720         unregister_reboot_notifier(&md_notifier);
3721         unregister_sysctl_table(raid_table_header);
3722         remove_proc_entry("mdstat", NULL);
3723         ITERATE_MDDEV(mddev,tmp) {
3724                 struct gendisk *disk = mddev->gendisk;
3725                 if (!disk)
3726                         continue;
3727                 export_array(mddev);
3728                 del_gendisk(disk);
3729                 put_disk(disk);
3730                 mddev->gendisk = NULL;
3731                 mddev_put(mddev);
3732         }
3733 }
3734
3735 module_init(md_init)
3736 module_exit(md_exit)
3737
3738 EXPORT_SYMBOL(register_md_personality);
3739 EXPORT_SYMBOL(unregister_md_personality);
3740 EXPORT_SYMBOL(md_error);
3741 EXPORT_SYMBOL(md_done_sync);
3742 EXPORT_SYMBOL(md_write_start);
3743 EXPORT_SYMBOL(md_write_end);
3744 EXPORT_SYMBOL(md_handle_safemode);
3745 EXPORT_SYMBOL(md_register_thread);
3746 EXPORT_SYMBOL(md_unregister_thread);
3747 EXPORT_SYMBOL(md_wakeup_thread);
3748 EXPORT_SYMBOL(md_print_devices);
3749 EXPORT_SYMBOL(md_check_recovery);
3750 MODULE_LICENSE("GPL");