drivers/md/md.c

   1 /*
   2    md.c : Multiple Devices driver for Linux
   3           Copyright (C) 1998, 1999, 2000 Ingo Molnar
   4
   5      completely rewritten, based on the MD driver code from Marc Zyngier
   6
   7    Changes:
   8
   9    - RAID-1/RAID-5 extensions by Miguel de Icaza, Gadi Oxman, Ingo Molnar
  10    - RAID-6 extensions by H. Peter Anvin <hpa@zytor.com>
  11    - boot support for linear and striped mode by Harald Hoyer <HarryH@Royal.Net>
  12    - kerneld support by Boris Tobotras <boris@xtalk.msk.su>
  13    - kmod support by: Cyrus Durgin
  14    - RAID0 bugfixes: Mark Anthony Lisher <markal@iname.com>
  15    - Devfs support by Richard Gooch <rgooch@atnf.csiro.au>
  16
  17    - lots of fixes and improvements to the RAID1/RAID5 and generic
  18      RAID code (such as request based resynchronization):
  19
  20      Neil Brown <neilb@cse.unsw.edu.au>.
  21
  22    - persistent bitmap code
  23      Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.
  24
  25    This program is free software; you can redistribute it and/or modify
  26    it under the terms of the GNU General Public License as published by
  27    the Free Software Foundation; either version 2, or (at your option)
  28    any later version.
  29
  30    You should have received a copy of the GNU General Public License
  31    (for example /usr/src/linux/COPYING); if not, write to the Free
  32    Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  33 */
  34
  35 #include <linux/module.h>
  36 #include <linux/config.h>
  37 #include <linux/kthread.h>
  38 #include <linux/linkage.h>
  39 #include <linux/raid/md.h>
  40 #include <linux/raid/bitmap.h>
  41 #include <linux/sysctl.h>
  42 #include <linux/devfs_fs_kernel.h>
  43 #include <linux/buffer_head.h> /* for invalidate_bdev */
  44 #include <linux/suspend.h>
  45 #include <linux/poll.h>
  46
  47 #include <linux/init.h>
  48
  49 #include <linux/file.h>
  50
  51 #ifdef CONFIG_KMOD
  52 #include <linux/kmod.h>
  53 #endif
  54
  55 #include <asm/unaligned.h>
  56
  57 #define MAJOR_NR MD_MAJOR
  58 #define MD_DRIVER
  59
  60 /* 63 partitions with the alternate major number (mdp) */
  61 #define MdpMinorShift 6
  62
  63 #define DEBUG 0
  64 #define dprintk(x...) ((void)(DEBUG && printk(x)))
  65
  66
  67 #ifndef MODULE
  68 static void autostart_arrays (int part);
  69 #endif
  70
  71 static LIST_HEAD(pers_list);
  72 static DEFINE_SPINLOCK(pers_lock);
  73
  74 /*
  75  * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
  76  * is 1000 KB/sec, so the extra system load does not show up that much.
  77  * Increase it if you want to have more _guaranteed_ speed. Note that
  78  * the RAID driver will use the maximum available bandwidth if the IO
  79  * subsystem is idle. There is also an 'absolute maximum' reconstruction
  80  * speed limit - in case reconstruction slows down your system despite
  81  * idle IO detection.
  82  *
  83  * you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
  84  */
  85
  86 static int sysctl_speed_limit_min = 1000;
  87 static int sysctl_speed_limit_max = 200000;
  88
  89 static struct ctl_table_header *raid_table_header;
  90
  91 static ctl_table raid_table[] = {
  92         {
  93                 .ctl_name       = DEV_RAID_SPEED_LIMIT_MIN,
  94                 .procname       = "speed_limit_min",
  95                 .data           = &sysctl_speed_limit_min,
  96                 .maxlen         = sizeof(int),
  97                 .mode           = 0644,
  98                 .proc_handler   = &proc_dointvec,
  99         },
 100         {
 101                 .ctl_name       = DEV_RAID_SPEED_LIMIT_MAX,
 102                 .procname       = "speed_limit_max",
 103                 .data           = &sysctl_speed_limit_max,
 104                 .maxlen         = sizeof(int),
 105                 .mode           = 0644,
 106                 .proc_handler   = &proc_dointvec,
 107         },
 108         { .ctl_name = 0 }
 109 };
 110
 111 static ctl_table raid_dir_table[] = {
 112         {
 113                 .ctl_name       = DEV_RAID,
 114                 .procname       = "raid",
 115                 .maxlen         = 0,
 116                 .mode           = 0555,
 117                 .child          = raid_table,
 118         },
 119         { .ctl_name = 0 }
 120 };
 121
 122 static ctl_table raid_root_table[] = {
 123         {
 124                 .ctl_name       = CTL_DEV,
 125                 .procname       = "dev",
 126                 .maxlen         = 0,
 127                 .mode           = 0555,
 128                 .child          = raid_dir_table,
 129         },
 130         { .ctl_name = 0 }
 131 };
 132
 133 static struct block_device_operations md_fops;
 134
 135 static int start_readonly;
 136
 137 /*
 138  * We have a system wide 'event count' that is incremented
 139  * on any 'interesting' event, and readers of /proc/mdstat
 140  * can use 'poll' or 'select' to find out when the event
 141  * count increases.
 142  *
 143  * Events are:
 144  *  start array, stop array, error, add device, remove device,
 145  *  start build, activate spare
 146  */
 147 static DECLARE_WAIT_QUEUE_HEAD(md_event_waiters);
 148 static atomic_t md_event_count;
 149 static void md_new_event(mddev_t *mddev)
 150 {
 151         atomic_inc(&md_event_count);
 152         wake_up(&md_event_waiters);
 153 }
 154
 155 /*
 156  * Enables to iterate over all existing md arrays
 157  * all_mddevs_lock protects this list.
 158  */
 159 static LIST_HEAD(all_mddevs);
 160 static DEFINE_SPINLOCK(all_mddevs_lock);
 161
 162
 163 /*
 164  * iterates through all used mddevs in the system.
 165  * We take care to grab the all_mddevs_lock whenever navigating
 166  * the list, and to always hold a refcount when unlocked.
 167  * Any code which breaks out of this loop while own
 168  * a reference to the current mddev and must mddev_put it.
 169  */
 170 #define ITERATE_MDDEV(mddev,tmp)                                        \
 171                                                                         \
 172         for (({ spin_lock(&all_mddevs_lock);                            \
 173                 tmp = all_mddevs.next;                                  \
 174                 mddev = NULL;});                                        \
 175              ({ if (tmp != &all_mddevs)                                 \
 176                         mddev_get(list_entry(tmp, mddev_t, all_mddevs));\
 177                 spin_unlock(&all_mddevs_lock);                          \
 178                 if (mddev) mddev_put(mddev);                            \
 179                 mddev = list_entry(tmp, mddev_t, all_mddevs);           \
 180                 tmp != &all_mddevs;});                                  \
 181              ({ spin_lock(&all_mddevs_lock);                            \
 182                 tmp = tmp->next;})                                      \
 183                 )
 184
 185
 186 static int md_fail_request (request_queue_t *q, struct bio *bio)
 187 {
 188         bio_io_error(bio, bio->bi_size);
 189         return 0;
 190 }
 191
 192 static inline mddev_t *mddev_get(mddev_t *mddev)
 193 {
 194         atomic_inc(&mddev->active);
 195         return mddev;
 196 }
 197
 198 static void mddev_put(mddev_t *mddev)
 199 {
 200         if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
 201                 return;
 202         if (!mddev->raid_disks && list_empty(&mddev->disks)) {
 203                 list_del(&mddev->all_mddevs);
 204                 blk_put_queue(mddev->queue);
 205                 kobject_unregister(&mddev->kobj);
 206         }
 207         spin_unlock(&all_mddevs_lock);
 208 }
 209
 210 static mddev_t * mddev_find(dev_t unit)
 211 {
 212         mddev_t *mddev, *new = NULL;
 213
 214  retry:
 215         spin_lock(&all_mddevs_lock);
 216         list_for_each_entry(mddev, &all_mddevs, all_mddevs)
 217                 if (mddev->unit == unit) {
 218                         mddev_get(mddev);
 219                         spin_unlock(&all_mddevs_lock);
 220                         kfree(new);
 221                         return mddev;
 222                 }
 223
 224         if (new) {
 225                 list_add(&new->all_mddevs, &all_mddevs);
 226                 spin_unlock(&all_mddevs_lock);
 227                 return new;
 228         }
 229         spin_unlock(&all_mddevs_lock);
 230
 231         new = kzalloc(sizeof(*new), GFP_KERNEL);
 232         if (!new)
 233                 return NULL;
 234
 235         new->unit = unit;
 236         if (MAJOR(unit) == MD_MAJOR)
 237                 new->md_minor = MINOR(unit);
 238         else
 239                 new->md_minor = MINOR(unit) >> MdpMinorShift;
 240
 241         init_MUTEX(&new->reconfig_sem);
 242         INIT_LIST_HEAD(&new->disks);
 243         INIT_LIST_HEAD(&new->all_mddevs);
 244         init_timer(&new->safemode_timer);
 245         atomic_set(&new->active, 1);
 246         spin_lock_init(&new->write_lock);
 247         init_waitqueue_head(&new->sb_wait);
 248
 249         new->queue = blk_alloc_queue(GFP_KERNEL);
 250         if (!new->queue) {
 251                 kfree(new);
 252                 return NULL;
 253         }
 254
 255         blk_queue_make_request(new->queue, md_fail_request);
 256
 257         goto retry;
 258 }
 259
 260 static inline int mddev_lock(mddev_t * mddev)
 261 {
 262         return down_interruptible(&mddev->reconfig_sem);
 263 }
 264
 265 static inline void mddev_lock_uninterruptible(mddev_t * mddev)
 266 {
 267         down(&mddev->reconfig_sem);
 268 }
 269
 270 static inline int mddev_trylock(mddev_t * mddev)
 271 {
 272         return down_trylock(&mddev->reconfig_sem);
 273 }
 274
 275 static inline void mddev_unlock(mddev_t * mddev)
 276 {
 277         up(&mddev->reconfig_sem);
 278
 279         md_wakeup_thread(mddev->thread);
 280 }
 281
 282 static mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr)
 283 {
 284         mdk_rdev_t * rdev;
 285         struct list_head *tmp;
 286
 287         ITERATE_RDEV(mddev,rdev,tmp) {
 288                 if (rdev->desc_nr == nr)
 289                         return rdev;
 290         }
 291         return NULL;
 292 }
 293
 294 static mdk_rdev_t * find_rdev(mddev_t * mddev, dev_t dev)
 295 {
 296         struct list_head *tmp;
 297         mdk_rdev_t *rdev;
 298
 299         ITERATE_RDEV(mddev,rdev,tmp) {
 300                 if (rdev->bdev->bd_dev == dev)
 301                         return rdev;
 302         }
 303         return NULL;
 304 }
 305
 306 static struct mdk_personality *find_pers(int level, char *clevel)
 307 {
 308         struct mdk_personality *pers;
 309         list_for_each_entry(pers, &pers_list, list) {
 310                 if (level != LEVEL_NONE && pers->level == level)
 311                         return pers;
 312                 if (strcmp(pers->name, clevel)==0)
 313                         return pers;
 314         }
 315         return NULL;
 316 }
 317
 318 static inline sector_t calc_dev_sboffset(struct block_device *bdev)
 319 {
 320         sector_t size = bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
 321         return MD_NEW_SIZE_BLOCKS(size);
 322 }
 323
 324 static sector_t calc_dev_size(mdk_rdev_t *rdev, unsigned chunk_size)
 325 {
 326         sector_t size;
 327
 328         size = rdev->sb_offset;
 329
 330         if (chunk_size)
 331                 size &= ~((sector_t)chunk_size/1024 - 1);
 332         return size;
 333 }
 334
 335 static int alloc_disk_sb(mdk_rdev_t * rdev)
 336 {
 337         if (rdev->sb_page)
 338                 MD_BUG();
 339
 340         rdev->sb_page = alloc_page(GFP_KERNEL);
 341         if (!rdev->sb_page) {
 342                 printk(KERN_ALERT "md: out of memory.\n");
 343                 return -EINVAL;
 344         }
 345
 346         return 0;
 347 }
 348
 349 static void free_disk_sb(mdk_rdev_t * rdev)
 350 {
 351         if (rdev->sb_page) {
 352                 put_page(rdev->sb_page);
 353                 rdev->sb_loaded = 0;
 354                 rdev->sb_page = NULL;
 355                 rdev->sb_offset = 0;
 356                 rdev->size = 0;
 357         }
 358 }
 359
 360
 361 static int super_written(struct bio *bio, unsigned int bytes_done, int error)
 362 {
 363         mdk_rdev_t *rdev = bio->bi_private;
 364         mddev_t *mddev = rdev->mddev;
 365         if (bio->bi_size)
 366                 return 1;
 367
 368         if (error || !test_bit(BIO_UPTODATE, &bio->bi_flags))
 369                 md_error(mddev, rdev);
 370
 371         if (atomic_dec_and_test(&mddev->pending_writes))
 372                 wake_up(&mddev->sb_wait);
 373         bio_put(bio);
 374         return 0;
 375 }
 376
 377 static int super_written_barrier(struct bio *bio, unsigned int bytes_done, int error)
 378 {
 379         struct bio *bio2 = bio->bi_private;
 380         mdk_rdev_t *rdev = bio2->bi_private;
 381         mddev_t *mddev = rdev->mddev;
 382         if (bio->bi_size)
 383                 return 1;
 384
 385         if (!test_bit(BIO_UPTODATE, &bio->bi_flags) &&
 386             error == -EOPNOTSUPP) {
 387                 unsigned long flags;
 388                 /* barriers don't appear to be supported :-( */
 389                 set_bit(BarriersNotsupp, &rdev->flags);
 390                 mddev->barriers_work = 0;
 391                 spin_lock_irqsave(&mddev->write_lock, flags);
 392                 bio2->bi_next = mddev->biolist;
 393                 mddev->biolist = bio2;
 394                 spin_unlock_irqrestore(&mddev->write_lock, flags);
 395                 wake_up(&mddev->sb_wait);
 396                 bio_put(bio);
 397                 return 0;
 398         }
 399         bio_put(bio2);
 400         bio->bi_private = rdev;
 401         return super_written(bio, bytes_done, error);
 402 }
 403
 404 void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev,
 405                    sector_t sector, int size, struct page *page)
 406 {
 407         /* write first size bytes of page to sector of rdev
 408          * Increment mddev->pending_writes before returning
 409          * and decrement it on completion, waking up sb_wait
 410          * if zero is reached.
 411          * If an error occurred, call md_error
 412          *
 413          * As we might need to resubmit the request if BIO_RW_BARRIER
 414          * causes ENOTSUPP, we allocate a spare bio...
 415          */
 416         struct bio *bio = bio_alloc(GFP_NOIO, 1);
 417         int rw = (1<<BIO_RW) | (1<<BIO_RW_SYNC);
 418
 419         bio->bi_bdev = rdev->bdev;
 420         bio->bi_sector = sector;
 421         bio_add_page(bio, page, size, 0);
 422         bio->bi_private = rdev;
 423         bio->bi_end_io = super_written;
 424         bio->bi_rw = rw;
 425
 426         atomic_inc(&mddev->pending_writes);
 427         if (!test_bit(BarriersNotsupp, &rdev->flags)) {
 428                 struct bio *rbio;
 429                 rw |= (1<<BIO_RW_BARRIER);
 430                 rbio = bio_clone(bio, GFP_NOIO);
 431                 rbio->bi_private = bio;
 432                 rbio->bi_end_io = super_written_barrier;
 433                 submit_bio(rw, rbio);
 434         } else
 435                 submit_bio(rw, bio);
 436 }
 437
 438 void md_super_wait(mddev_t *mddev)
 439 {
 440         /* wait for all superblock writes that were scheduled to complete.
 441          * if any had to be retried (due to BARRIER problems), retry them
 442          */
 443         DEFINE_WAIT(wq);
 444         for(;;) {
 445                 prepare_to_wait(&mddev->sb_wait, &wq, TASK_UNINTERRUPTIBLE);
 446                 if (atomic_read(&mddev->pending_writes)==0)
 447                         break;
 448                 while (mddev->biolist) {
 449                         struct bio *bio;
 450                         spin_lock_irq(&mddev->write_lock);
 451                         bio = mddev->biolist;
 452                         mddev->biolist = bio->bi_next ;
 453                         bio->bi_next = NULL;
 454                         spin_unlock_irq(&mddev->write_lock);
 455                         submit_bio(bio->bi_rw, bio);
 456                 }
 457                 schedule();
 458         }
 459         finish_wait(&mddev->sb_wait, &wq);
 460 }
 461
 462 static int bi_complete(struct bio *bio, unsigned int bytes_done, int error)
 463 {
 464         if (bio->bi_size)
 465                 return 1;
 466
 467         complete((struct completion*)bio->bi_private);
 468         return 0;
 469 }
 470
 471 int sync_page_io(struct block_device *bdev, sector_t sector, int size,
 472                    struct page *page, int rw)
 473 {
 474         struct bio *bio = bio_alloc(GFP_NOIO, 1);
 475         struct completion event;
 476         int ret;
 477
 478         rw |= (1 << BIO_RW_SYNC);
 479
 480         bio->bi_bdev = bdev;
 481         bio->bi_sector = sector;
 482         bio_add_page(bio, page, size, 0);
 483         init_completion(&event);
 484         bio->bi_private = &event;
 485         bio->bi_end_io = bi_complete;
 486         submit_bio(rw, bio);
 487         wait_for_completion(&event);
 488
 489         ret = test_bit(BIO_UPTODATE, &bio->bi_flags);
 490         bio_put(bio);
 491         return ret;
 492 }
 493 EXPORT_SYMBOL_GPL(sync_page_io);
 494
 495 static int read_disk_sb(mdk_rdev_t * rdev, int size)
 496 {
 497         char b[BDEVNAME_SIZE];
 498         if (!rdev->sb_page) {
 499                 MD_BUG();
 500                 return -EINVAL;
 501         }
 502         if (rdev->sb_loaded)
 503                 return 0;
 504
 505
 506         if (!sync_page_io(rdev->bdev, rdev->sb_offset<<1, size, rdev->sb_page, READ))
 507                 goto fail;
 508         rdev->sb_loaded = 1;
 509         return 0;
 510
 511 fail:
 512         printk(KERN_WARNING "md: disabled device %s, could not read superblock.\n",
 513                 bdevname(rdev->bdev,b));
 514         return -EINVAL;
 515 }
 516
 517 static int uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 518 {
 519         if (    (sb1->set_uuid0 == sb2->set_uuid0) &&
 520                 (sb1->set_uuid1 == sb2->set_uuid1) &&
 521                 (sb1->set_uuid2 == sb2->set_uuid2) &&
 522                 (sb1->set_uuid3 == sb2->set_uuid3))
 523
 524                 return 1;
 525
 526         return 0;
 527 }
 528
 529
 530 static int sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 531 {
 532         int ret;
 533         mdp_super_t *tmp1, *tmp2;
 534
 535         tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
 536         tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
 537
 538         if (!tmp1 || !tmp2) {
 539                 ret = 0;
 540                 printk(KERN_INFO "md.c: sb1 is not equal to sb2!\n");
 541                 goto abort;
 542         }
 543
 544         *tmp1 = *sb1;
 545         *tmp2 = *sb2;
 546
 547         /*
 548          * nr_disks is not constant
 549          */
 550         tmp1->nr_disks = 0;
 551         tmp2->nr_disks = 0;
 552
 553         if (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4))
 554                 ret = 0;
 555         else
 556                 ret = 1;
 557
 558 abort:
 559         kfree(tmp1);
 560         kfree(tmp2);
 561         return ret;
 562 }
 563
 564 static unsigned int calc_sb_csum(mdp_super_t * sb)
 565 {
 566         unsigned int disk_csum, csum;
 567
 568         disk_csum = sb->sb_csum;
 569         sb->sb_csum = 0;
 570         csum = csum_partial((void *)sb, MD_SB_BYTES, 0);
 571         sb->sb_csum = disk_csum;
 572         return csum;
 573 }
 574
 575
 576 /*
 577  * Handle superblock details.
 578  * We want to be able to handle multiple superblock formats
 579  * so we have a common interface to them all, and an array of
 580  * different handlers.
 581  * We rely on user-space to write the initial superblock, and support
 582  * reading and updating of superblocks.
 583  * Interface methods are:
 584  *   int load_super(mdk_rdev_t *dev, mdk_rdev_t *refdev, int minor_version)
 585  *      loads and validates a superblock on dev.
 586  *      if refdev != NULL, compare superblocks on both devices
 587  *    Return:
 588  *      0 - dev has a superblock that is compatible with refdev
 589  *      1 - dev has a superblock that is compatible and newer than refdev
 590  *          so dev should be used as the refdev in future
 591  *     -EINVAL superblock incompatible or invalid
 592  *     -othererror e.g. -EIO
 593  *
 594  *   int validate_super(mddev_t *mddev, mdk_rdev_t *dev)
 595  *      Verify that dev is acceptable into mddev.
 596  *       The first time, mddev->raid_disks will be 0, and data from
 597  *       dev should be merged in.  Subsequent calls check that dev
 598  *       is new enough.  Return 0 or -EINVAL
 599  *
 600  *   void sync_super(mddev_t *mddev, mdk_rdev_t *dev)
 601  *     Update the superblock for rdev with data in mddev
 602  *     This does not write to disc.
 603  *
 604  */
 605
 606 struct super_type  {
 607         char            *name;
 608         struct module   *owner;
 609         int             (*load_super)(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version);
 610         int             (*validate_super)(mddev_t *mddev, mdk_rdev_t *rdev);
 611         void            (*sync_super)(mddev_t *mddev, mdk_rdev_t *rdev);
 612 };
 613
 614 /*
 615  * load_super for 0.90.0
 616  */
 617 static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
 618 {
 619         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
 620         mdp_super_t *sb;
 621         int ret;
 622         sector_t sb_offset;
 623
 624         /*
 625          * Calculate the position of the superblock,
 626          * it's at the end of the disk.
 627          *
 628          * It also happens to be a multiple of 4Kb.
 629          */
 630         sb_offset = calc_dev_sboffset(rdev->bdev);
 631         rdev->sb_offset = sb_offset;
 632
 633         ret = read_disk_sb(rdev, MD_SB_BYTES);
 634         if (ret) return ret;
 635
 636         ret = -EINVAL;
 637
 638         bdevname(rdev->bdev, b);
 639         sb = (mdp_super_t*)page_address(rdev->sb_page);
 640
 641         if (sb->md_magic != MD_SB_MAGIC) {
 642                 printk(KERN_ERR "md: invalid raid superblock magic on %s\n",
 643                        b);
 644                 goto abort;
 645         }
 646
 647         if (sb->major_version != 0 ||
 648             sb->minor_version != 90) {
 649                 printk(KERN_WARNING "Bad version number %d.%d on %s\n",
 650                         sb->major_version, sb->minor_version,
 651                         b);
 652                 goto abort;
 653         }
 654
 655         if (sb->raid_disks <= 0)
 656                 goto abort;
 657
 658         if (csum_fold(calc_sb_csum(sb)) != csum_fold(sb->sb_csum)) {
 659                 printk(KERN_WARNING "md: invalid superblock checksum on %s\n",
 660                         b);
 661                 goto abort;
 662         }
 663
 664         rdev->preferred_minor = sb->md_minor;
 665         rdev->data_offset = 0;
 666         rdev->sb_size = MD_SB_BYTES;
 667
 668         if (sb->level == LEVEL_MULTIPATH)
 669                 rdev->desc_nr = -1;
 670         else
 671                 rdev->desc_nr = sb->this_disk.number;
 672
 673         if (refdev == 0)
 674                 ret = 1;
 675         else {
 676                 __u64 ev1, ev2;
 677                 mdp_super_t *refsb = (mdp_super_t*)page_address(refdev->sb_page);
 678                 if (!uuid_equal(refsb, sb)) {
 679                         printk(KERN_WARNING "md: %s has different UUID to %s\n",
 680                                 b, bdevname(refdev->bdev,b2));
 681                         goto abort;
 682                 }
 683                 if (!sb_equal(refsb, sb)) {
 684                         printk(KERN_WARNING "md: %s has same UUID"
 685                                " but different superblock to %s\n",
 686                                b, bdevname(refdev->bdev, b2));
 687                         goto abort;
 688                 }
 689                 ev1 = md_event(sb);
 690                 ev2 = md_event(refsb);
 691                 if (ev1 > ev2)
 692                         ret = 1;
 693                 else
 694                         ret = 0;
 695         }
 696         rdev->size = calc_dev_size(rdev, sb->chunk_size);
 697
 698         if (rdev->size < sb->size && sb->level > 1)
 699                 /* "this cannot possibly happen" ... */
 700                 ret = -EINVAL;
 701
 702  abort:
 703         return ret;
 704 }
 705
 706 /*
 707  * validate_super for 0.90.0
 708  */
 709 static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
 710 {
 711         mdp_disk_t *desc;
 712         mdp_super_t *sb = (mdp_super_t *)page_address(rdev->sb_page);
 713
 714         rdev->raid_disk = -1;
 715         rdev->flags = 0;
 716         if (mddev->raid_disks == 0) {
 717                 mddev->major_version = 0;
 718                 mddev->minor_version = sb->minor_version;
 719                 mddev->patch_version = sb->patch_version;
 720                 mddev->persistent = ! sb->not_persistent;
 721                 mddev->chunk_size = sb->chunk_size;
 722                 mddev->ctime = sb->ctime;
 723                 mddev->utime = sb->utime;
 724                 mddev->level = sb->level;
 725                 mddev->clevel[0] = 0;
 726                 mddev->layout = sb->layout;
 727                 mddev->raid_disks = sb->raid_disks;
 728                 mddev->size = sb->size;
 729                 mddev->events = md_event(sb);
 730                 mddev->bitmap_offset = 0;
 731                 mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
 732
 733                 if (sb->state & (1<<MD_SB_CLEAN))
 734                         mddev->recovery_cp = MaxSector;
 735                 else {
 736                         if (sb->events_hi == sb->cp_events_hi &&
 737                                 sb->events_lo == sb->cp_events_lo) {
 738                                 mddev->recovery_cp = sb->recovery_cp;
 739                         } else
 740                                 mddev->recovery_cp = 0;
 741                 }
 742
 743                 memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
 744                 memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
 745                 memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
 746                 memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
 747
 748                 mddev->max_disks = MD_SB_DISKS;
 749
 750                 if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
 751                     mddev->bitmap_file == NULL) {
 752                         if (mddev->level != 1 && mddev->level != 5 && mddev->level != 6
 753                             && mddev->level != 10) {
 754                                 /* FIXME use a better test */
 755                                 printk(KERN_WARNING "md: bitmaps not supported for this level.\n");
 756                                 return -EINVAL;
 757                         }
 758                         mddev->bitmap_offset = mddev->default_bitmap_offset;
 759                 }
 760
 761         } else if (mddev->pers == NULL) {
 762                 /* Insist on good event counter while assembling */
 763                 __u64 ev1 = md_event(sb);
 764                 ++ev1;
 765                 if (ev1 < mddev->events)
 766                         return -EINVAL;
 767         } else if (mddev->bitmap) {
 768                 /* if adding to array with a bitmap, then we can accept an
 769                  * older device ... but not too old.
 770                  */
 771                 __u64 ev1 = md_event(sb);
 772                 if (ev1 < mddev->bitmap->events_cleared)
 773                         return 0;
 774         } else /* just a hot-add of a new device, leave raid_disk at -1 */
 775                 return 0;
 776
 777         if (mddev->level != LEVEL_MULTIPATH) {
 778                 desc = sb->disks + rdev->desc_nr;
 779
 780                 if (desc->state & (1<<MD_DISK_FAULTY))
 781                         set_bit(Faulty, &rdev->flags);
 782                 else if (desc->state & (1<<MD_DISK_SYNC) &&
 783                          desc->raid_disk < mddev->raid_disks) {
 784                         set_bit(In_sync, &rdev->flags);
 785                         rdev->raid_disk = desc->raid_disk;
 786                 }
 787                 if (desc->state & (1<<MD_DISK_WRITEMOSTLY))
 788                         set_bit(WriteMostly, &rdev->flags);
 789         } else /* MULTIPATH are always insync */
 790                 set_bit(In_sync, &rdev->flags);
 791         return 0;
 792 }
 793
 794 /*
 795  * sync_super for 0.90.0
 796  */
 797 static void super_90_sync(mddev_t *mddev, mdk_rdev_t *rdev)
 798 {
 799         mdp_super_t *sb;
 800         struct list_head *tmp;
 801         mdk_rdev_t *rdev2;
 802         int next_spare = mddev->raid_disks;
 803
 804
 805         /* make rdev->sb match mddev data..
 806          *
 807          * 1/ zero out disks
 808          * 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
 809          * 3/ any empty disks < next_spare become removed
 810          *
 811          * disks[0] gets initialised to REMOVED because
 812          * we cannot be sure from other fields if it has
 813          * been initialised or not.
 814          */
 815         int i;
 816         int active=0, working=0,failed=0,spare=0,nr_disks=0;
 817
 818         rdev->sb_size = MD_SB_BYTES;
 819
 820         sb = (mdp_super_t*)page_address(rdev->sb_page);
 821
 822         memset(sb, 0, sizeof(*sb));
 823
 824         sb->md_magic = MD_SB_MAGIC;
 825         sb->major_version = mddev->major_version;
 826         sb->minor_version = mddev->minor_version;
 827         sb->patch_version = mddev->patch_version;
 828         sb->gvalid_words  = 0; /* ignored */
 829         memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
 830         memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
 831         memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
 832         memcpy(&sb->set_uuid3, mddev->uuid+12,4);
 833
 834         sb->ctime = mddev->ctime;
 835         sb->level = mddev->level;
 836         sb->size  = mddev->size;
 837         sb->raid_disks = mddev->raid_disks;
 838         sb->md_minor = mddev->md_minor;
 839         sb->not_persistent = !mddev->persistent;
 840         sb->utime = mddev->utime;
 841         sb->state = 0;
 842         sb->events_hi = (mddev->events>>32);
 843         sb->events_lo = (u32)mddev->events;
 844
 845         if (mddev->in_sync)
 846         {
 847                 sb->recovery_cp = mddev->recovery_cp;
 848                 sb->cp_events_hi = (mddev->events>>32);
 849                 sb->cp_events_lo = (u32)mddev->events;
 850                 if (mddev->recovery_cp == MaxSector)
 851                         sb->state = (1<< MD_SB_CLEAN);
 852         } else
 853                 sb->recovery_cp = 0;
 854
 855         sb->layout = mddev->layout;
 856         sb->chunk_size = mddev->chunk_size;
 857
 858         if (mddev->bitmap && mddev->bitmap_file == NULL)
 859                 sb->state |= (1<<MD_SB_BITMAP_PRESENT);
 860
 861         sb->disks[0].state = (1<<MD_DISK_REMOVED);
 862         ITERATE_RDEV(mddev,rdev2,tmp) {
 863                 mdp_disk_t *d;
 864                 int desc_nr;
 865                 if (rdev2->raid_disk >= 0 && test_bit(In_sync, &rdev2->flags)
 866                     && !test_bit(Faulty, &rdev2->flags))
 867                         desc_nr = rdev2->raid_disk;
 868                 else
 869                         desc_nr = next_spare++;
 870                 rdev2->desc_nr = desc_nr;
 871                 d = &sb->disks[rdev2->desc_nr];
 872                 nr_disks++;
 873                 d->number = rdev2->desc_nr;
 874                 d->major = MAJOR(rdev2->bdev->bd_dev);
 875                 d->minor = MINOR(rdev2->bdev->bd_dev);
 876                 if (rdev2->raid_disk >= 0 && test_bit(In_sync, &rdev2->flags)
 877                     && !test_bit(Faulty, &rdev2->flags))
 878                         d->raid_disk = rdev2->raid_disk;
 879                 else
 880                         d->raid_disk = rdev2->desc_nr; /* compatibility */
 881                 if (test_bit(Faulty, &rdev2->flags)) {
 882                         d->state = (1<<MD_DISK_FAULTY);
 883                         failed++;
 884                 } else if (test_bit(In_sync, &rdev2->flags)) {
 885                         d->state = (1<<MD_DISK_ACTIVE);
 886                         d->state |= (1<<MD_DISK_SYNC);
 887                         active++;
 888                         working++;
 889                 } else {
 890                         d->state = 0;
 891                         spare++;
 892                         working++;
 893                 }
 894                 if (test_bit(WriteMostly, &rdev2->flags))
 895                         d->state |= (1<<MD_DISK_WRITEMOSTLY);
 896         }
 897         /* now set the "removed" and "faulty" bits on any missing devices */
 898         for (i=0 ; i < mddev->raid_disks ; i++) {
 899                 mdp_disk_t *d = &sb->disks[i];
 900                 if (d->state == 0 && d->number == 0) {
 901                         d->number = i;
 902                         d->raid_disk = i;
 903                         d->state = (1<<MD_DISK_REMOVED);
 904                         d->state |= (1<<MD_DISK_FAULTY);
 905                         failed++;
 906                 }
 907         }
 908         sb->nr_disks = nr_disks;
 909         sb->active_disks = active;
 910         sb->working_disks = working;
 911         sb->failed_disks = failed;
 912         sb->spare_disks = spare;
 913
 914         sb->this_disk = sb->disks[rdev->desc_nr];
 915         sb->sb_csum = calc_sb_csum(sb);
 916 }
 917
 918 /*
 919  * version 1 superblock
 920  */
 921
 922 static unsigned int calc_sb_1_csum(struct mdp_superblock_1 * sb)
 923 {
 924         unsigned int disk_csum, csum;
 925         unsigned long long newcsum;
 926         int size = 256 + le32_to_cpu(sb->max_dev)*2;
 927         unsigned int *isuper = (unsigned int*)sb;
 928         int i;
 929
 930         disk_csum = sb->sb_csum;
 931         sb->sb_csum = 0;
 932         newcsum = 0;
 933         for (i=0; size>=4; size -= 4 )
 934                 newcsum += le32_to_cpu(*isuper++);
 935
 936         if (size == 2)
 937                 newcsum += le16_to_cpu(*(unsigned short*) isuper);
 938
 939         csum = (newcsum & 0xffffffff) + (newcsum >> 32);
 940         sb->sb_csum = disk_csum;
 941         return cpu_to_le32(csum);
 942 }
 943
 944 static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
 945 {
 946         struct mdp_superblock_1 *sb;
 947         int ret;
 948         sector_t sb_offset;
 949         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
 950         int bmask;
 951
 952         /*
 953          * Calculate the position of the superblock.
 954          * It is always aligned to a 4K boundary and
 955          * depeding on minor_version, it can be:
 956          * 0: At least 8K, but less than 12K, from end of device
 957          * 1: At start of device
 958          * 2: 4K from start of device.
 959          */
 960         switch(minor_version) {
 961         case 0:
 962                 sb_offset = rdev->bdev->bd_inode->i_size >> 9;
 963                 sb_offset -= 8*2;
 964                 sb_offset &= ~(sector_t)(4*2-1);
 965                 /* convert from sectors to K */
 966                 sb_offset /= 2;
 967                 break;
 968         case 1:
 969                 sb_offset = 0;
 970                 break;
 971         case 2:
 972                 sb_offset = 4;
 973                 break;
 974         default:
 975                 return -EINVAL;
 976         }
 977         rdev->sb_offset = sb_offset;
 978
 979         /* superblock is rarely larger than 1K, but it can be larger,
 980          * and it is safe to read 4k, so we do that
 981          */
 982         ret = read_disk_sb(rdev, 4096);
 983         if (ret) return ret;
 984
 985
 986         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
 987
 988         if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
 989             sb->major_version != cpu_to_le32(1) ||
 990             le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
 991             le64_to_cpu(sb->super_offset) != (rdev->sb_offset<<1) ||
 992             (le32_to_cpu(sb->feature_map) & ~MD_FEATURE_ALL) != 0)
 993                 return -EINVAL;
 994
 995         if (calc_sb_1_csum(sb) != sb->sb_csum) {
 996                 printk("md: invalid superblock checksum on %s\n",
 997                         bdevname(rdev->bdev,b));
 998                 return -EINVAL;
 999         }
1000         if (le64_to_cpu(sb->data_size) < 10) {
1001                 printk("md: data_size too small on %s\n",
1002                        bdevname(rdev->bdev,b));
1003                 return -EINVAL;
1004         }
1005         rdev->preferred_minor = 0xffff;
1006         rdev->data_offset = le64_to_cpu(sb->data_offset);
1007         atomic_set(&rdev->corrected_errors, le32_to_cpu(sb->cnt_corrected_read));
1008
1009         rdev->sb_size = le32_to_cpu(sb->max_dev) * 2 + 256;
1010         bmask = queue_hardsect_size(rdev->bdev->bd_disk->queue)-1;
1011         if (rdev->sb_size & bmask)
1012                 rdev-> sb_size = (rdev->sb_size | bmask)+1;
1013
1014         if (refdev == 0)
1015                 return 1;
1016         else {
1017                 __u64 ev1, ev2;
1018                 struct mdp_superblock_1 *refsb =
1019                         (struct mdp_superblock_1*)page_address(refdev->sb_page);
1020
1021                 if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
1022                     sb->level != refsb->level ||
1023                     sb->layout != refsb->layout ||
1024                     sb->chunksize != refsb->chunksize) {
1025                         printk(KERN_WARNING "md: %s has strangely different"
1026                                 " superblock to %s\n",
1027                                 bdevname(rdev->bdev,b),
1028                                 bdevname(refdev->bdev,b2));
1029                         return -EINVAL;
1030                 }
1031                 ev1 = le64_to_cpu(sb->events);
1032                 ev2 = le64_to_cpu(refsb->events);
1033
1034                 if (ev1 > ev2)
1035                         return 1;
1036         }
1037         if (minor_version)
1038                 rdev->size = ((rdev->bdev->bd_inode->i_size>>9) - le64_to_cpu(sb->data_offset)) / 2;
1039         else
1040                 rdev->size = rdev->sb_offset;
1041         if (rdev->size < le64_to_cpu(sb->data_size)/2)
1042                 return -EINVAL;
1043         rdev->size = le64_to_cpu(sb->data_size)/2;
1044         if (le32_to_cpu(sb->chunksize))
1045                 rdev->size &= ~((sector_t)le32_to_cpu(sb->chunksize)/2 - 1);
1046
1047         if (le32_to_cpu(sb->size) > rdev->size*2)
1048                 return -EINVAL;
1049         return 0;
1050 }
1051
1052 static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
1053 {
1054         struct mdp_superblock_1 *sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1055
1056         rdev->raid_disk = -1;
1057         rdev->flags = 0;
1058         if (mddev->raid_disks == 0) {
1059                 mddev->major_version = 1;
1060                 mddev->patch_version = 0;
1061                 mddev->persistent = 1;
1062                 mddev->chunk_size = le32_to_cpu(sb->chunksize) << 9;
1063                 mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);
1064                 mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);
1065                 mddev->level = le32_to_cpu(sb->level);
1066                 mddev->clevel[0] = 0;
1067                 mddev->layout = le32_to_cpu(sb->layout);
1068                 mddev->raid_disks = le32_to_cpu(sb->raid_disks);
1069                 mddev->size = le64_to_cpu(sb->size)/2;
1070                 mddev->events = le64_to_cpu(sb->events);
1071                 mddev->bitmap_offset = 0;
1072                 mddev->default_bitmap_offset = 1024;
1073
1074                 mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
1075                 memcpy(mddev->uuid, sb->set_uuid, 16);
1076
1077                 mddev->max_disks =  (4096-256)/2;
1078
1079                 if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET) &&
1080                     mddev->bitmap_file == NULL ) {
1081                         if (mddev->level != 1 && mddev->level != 5 && mddev->level != 6
1082                             && mddev->level != 10) {
1083                                 printk(KERN_WARNING "md: bitmaps not supported for this level.\n");
1084                                 return -EINVAL;
1085                         }
1086                         mddev->bitmap_offset = (__s32)le32_to_cpu(sb->bitmap_offset);
1087                 }
1088         } else if (mddev->pers == NULL) {
1089                 /* Insist of good event counter while assembling */
1090                 __u64 ev1 = le64_to_cpu(sb->events);
1091                 ++ev1;
1092                 if (ev1 < mddev->events)
1093                         return -EINVAL;
1094         } else if (mddev->bitmap) {
1095                 /* If adding to array with a bitmap, then we can accept an
1096                  * older device, but not too old.
1097                  */
1098                 __u64 ev1 = le64_to_cpu(sb->events);
1099                 if (ev1 < mddev->bitmap->events_cleared)
1100                         return 0;
1101         } else /* just a hot-add of a new device, leave raid_disk at -1 */
1102                 return 0;
1103
1104         if (mddev->level != LEVEL_MULTIPATH) {
1105                 int role;
1106                 rdev->desc_nr = le32_to_cpu(sb->dev_number);
1107                 role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
1108                 switch(role) {
1109                 case 0xffff: /* spare */
1110                         break;
1111                 case 0xfffe: /* faulty */
1112                         set_bit(Faulty, &rdev->flags);
1113                         break;
1114                 default:
1115                         set_bit(In_sync, &rdev->flags);
1116                         rdev->raid_disk = role;
1117                         break;
1118                 }
1119                 if (sb->devflags & WriteMostly1)
1120                         set_bit(WriteMostly, &rdev->flags);
1121         } else /* MULTIPATH are always insync */
1122                 set_bit(In_sync, &rdev->flags);
1123
1124         return 0;
1125 }
1126
1127 static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
1128 {
1129         struct mdp_superblock_1 *sb;
1130         struct list_head *tmp;
1131         mdk_rdev_t *rdev2;
1132         int max_dev, i;
1133         /* make rdev->sb match mddev and rdev data. */
1134
1135         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1136
1137         sb->feature_map = 0;
1138         sb->pad0 = 0;
1139         memset(sb->pad1, 0, sizeof(sb->pad1));
1140         memset(sb->pad2, 0, sizeof(sb->pad2));
1141         memset(sb->pad3, 0, sizeof(sb->pad3));
1142
1143         sb->utime = cpu_to_le64((__u64)mddev->utime);
1144         sb->events = cpu_to_le64(mddev->events);
1145         if (mddev->in_sync)
1146                 sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
1147         else
1148                 sb->resync_offset = cpu_to_le64(0);
1149
1150         sb->cnt_corrected_read = atomic_read(&rdev->corrected_errors);
1151
1152         if (mddev->bitmap && mddev->bitmap_file == NULL) {
1153                 sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_offset);
1154                 sb->feature_map = cpu_to_le32(MD_FEATURE_BITMAP_OFFSET);
1155         }
1156
1157         max_dev = 0;
1158         ITERATE_RDEV(mddev,rdev2,tmp)
1159                 if (rdev2->desc_nr+1 > max_dev)
1160                         max_dev = rdev2->desc_nr+1;
1161
1162         sb->max_dev = cpu_to_le32(max_dev);
1163         for (i=0; i<max_dev;i++)
1164                 sb->dev_roles[i] = cpu_to_le16(0xfffe);
1165
1166         ITERATE_RDEV(mddev,rdev2,tmp) {
1167                 i = rdev2->desc_nr;
1168                 if (test_bit(Faulty, &rdev2->flags))
1169                         sb->dev_roles[i] = cpu_to_le16(0xfffe);
1170                 else if (test_bit(In_sync, &rdev2->flags))
1171                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1172                 else
1173                         sb->dev_roles[i] = cpu_to_le16(0xffff);
1174         }
1175
1176         sb->recovery_offset = cpu_to_le64(0); /* not supported yet */
1177         sb->sb_csum = calc_sb_1_csum(sb);
1178 }
1179
1180
1181 static struct super_type super_types[] = {
1182         [0] = {
1183                 .name   = "0.90.0",
1184                 .owner  = THIS_MODULE,
1185                 .load_super     = super_90_load,
1186                 .validate_super = super_90_validate,
1187                 .sync_super     = super_90_sync,
1188         },
1189         [1] = {
1190                 .name   = "md-1",
1191                 .owner  = THIS_MODULE,
1192                 .load_super     = super_1_load,
1193                 .validate_super = super_1_validate,
1194                 .sync_super     = super_1_sync,
1195         },
1196 };
1197
1198 static mdk_rdev_t * match_dev_unit(mddev_t *mddev, mdk_rdev_t *dev)
1199 {
1200         struct list_head *tmp;
1201         mdk_rdev_t *rdev;
1202
1203         ITERATE_RDEV(mddev,rdev,tmp)
1204                 if (rdev->bdev->bd_contains == dev->bdev->bd_contains)
1205                         return rdev;
1206
1207         return NULL;
1208 }
1209
1210 static int match_mddev_units(mddev_t *mddev1, mddev_t *mddev2)
1211 {
1212         struct list_head *tmp;
1213         mdk_rdev_t *rdev;
1214
1215         ITERATE_RDEV(mddev1,rdev,tmp)
1216                 if (match_dev_unit(mddev2, rdev))
1217                         return 1;
1218
1219         return 0;
1220 }
1221
1222 static LIST_HEAD(pending_raid_disks);
1223
1224 static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
1225 {
1226         mdk_rdev_t *same_pdev;
1227         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1228         struct kobject *ko;
1229
1230         if (rdev->mddev) {
1231                 MD_BUG();
1232                 return -EINVAL;
1233         }
1234         /* make sure rdev->size exceeds mddev->size */
1235         if (rdev->size && (mddev->size == 0 || rdev->size < mddev->size)) {
1236                 if (mddev->pers)
1237                         /* Cannot change size, so fail */
1238                         return -ENOSPC;
1239                 else
1240                         mddev->size = rdev->size;
1241         }
1242         same_pdev = match_dev_unit(mddev, rdev);
1243         if (same_pdev)
1244                 printk(KERN_WARNING
1245                         "%s: WARNING: %s appears to be on the same physical"
1246                         " disk as %s. True\n     protection against single-disk"
1247                         " failure might be compromised.\n",
1248                         mdname(mddev), bdevname(rdev->bdev,b),
1249                         bdevname(same_pdev->bdev,b2));
1250
1251         /* Verify rdev->desc_nr is unique.
1252          * If it is -1, assign a free number, else
1253          * check number is not in use
1254          */
1255         if (rdev->desc_nr < 0) {
1256                 int choice = 0;
1257                 if (mddev->pers) choice = mddev->raid_disks;
1258                 while (find_rdev_nr(mddev, choice))
1259                         choice++;
1260                 rdev->desc_nr = choice;
1261         } else {
1262                 if (find_rdev_nr(mddev, rdev->desc_nr))
1263                         return -EBUSY;
1264         }
1265         bdevname(rdev->bdev,b);
1266         if (kobject_set_name(&rdev->kobj, "dev-%s", b) < 0)
1267                 return -ENOMEM;
1268
1269         list_add(&rdev->same_set, &mddev->disks);
1270         rdev->mddev = mddev;
1271         printk(KERN_INFO "md: bind<%s>\n", b);
1272
1273         rdev->kobj.parent = &mddev->kobj;
1274         kobject_add(&rdev->kobj);
1275
1276         if (rdev->bdev->bd_part)
1277                 ko = &rdev->bdev->bd_part->kobj;
1278         else
1279                 ko = &rdev->bdev->bd_disk->kobj;
1280         sysfs_create_link(&rdev->kobj, ko, "block");
1281         return 0;
1282 }
1283
1284 static void unbind_rdev_from_array(mdk_rdev_t * rdev)
1285 {
1286         char b[BDEVNAME_SIZE];
1287         if (!rdev->mddev) {
1288                 MD_BUG();
1289                 return;
1290         }
1291         list_del_init(&rdev->same_set);
1292         printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
1293         rdev->mddev = NULL;
1294         sysfs_remove_link(&rdev->kobj, "block");
1295         kobject_del(&rdev->kobj);
1296 }
1297
1298 /*
1299  * prevent the device from being mounted, repartitioned or
1300  * otherwise reused by a RAID array (or any other kernel
1301  * subsystem), by bd_claiming the device.
1302  */
1303 static int lock_rdev(mdk_rdev_t *rdev, dev_t dev)
1304 {
1305         int err = 0;
1306         struct block_device *bdev;
1307         char b[BDEVNAME_SIZE];
1308
1309         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
1310         if (IS_ERR(bdev)) {
1311                 printk(KERN_ERR "md: could not open %s.\n",
1312                         __bdevname(dev, b));
1313                 return PTR_ERR(bdev);
1314         }
1315         err = bd_claim(bdev, rdev);
1316         if (err) {
1317                 printk(KERN_ERR "md: could not bd_claim %s.\n",
1318                         bdevname(bdev, b));
1319                 blkdev_put(bdev);
1320                 return err;
1321         }
1322         rdev->bdev = bdev;
1323         return err;
1324 }
1325
1326 static void unlock_rdev(mdk_rdev_t *rdev)
1327 {
1328         struct block_device *bdev = rdev->bdev;
1329         rdev->bdev = NULL;
1330         if (!bdev)
1331                 MD_BUG();
1332         bd_release(bdev);
1333         blkdev_put(bdev);
1334 }
1335
1336 void md_autodetect_dev(dev_t dev);
1337
1338 static void export_rdev(mdk_rdev_t * rdev)
1339 {
1340         char b[BDEVNAME_SIZE];
1341         printk(KERN_INFO "md: export_rdev(%s)\n",
1342                 bdevname(rdev->bdev,b));
1343         if (rdev->mddev)
1344                 MD_BUG();
1345         free_disk_sb(rdev);
1346         list_del_init(&rdev->same_set);
1347 #ifndef MODULE
1348         md_autodetect_dev(rdev->bdev->bd_dev);
1349 #endif
1350         unlock_rdev(rdev);
1351         kobject_put(&rdev->kobj);
1352 }
1353
1354 static void kick_rdev_from_array(mdk_rdev_t * rdev)
1355 {
1356         unbind_rdev_from_array(rdev);
1357         export_rdev(rdev);
1358 }
1359
1360 static void export_array(mddev_t *mddev)
1361 {
1362         struct list_head *tmp;
1363         mdk_rdev_t *rdev;
1364
1365         ITERATE_RDEV(mddev,rdev,tmp) {
1366                 if (!rdev->mddev) {
1367                         MD_BUG();
1368                         continue;
1369                 }
1370                 kick_rdev_from_array(rdev);
1371         }
1372         if (!list_empty(&mddev->disks))
1373                 MD_BUG();
1374         mddev->raid_disks = 0;
1375         mddev->major_version = 0;
1376 }
1377
1378 static void print_desc(mdp_disk_t *desc)
1379 {
1380         printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
1381                 desc->major,desc->minor,desc->raid_disk,desc->state);
1382 }
1383
1384 static void print_sb(mdp_super_t *sb)
1385 {
1386         int i;
1387
1388         printk(KERN_INFO
1389                 "md:  SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
1390                 sb->major_version, sb->minor_version, sb->patch_version,
1391                 sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
1392                 sb->ctime);
1393         printk(KERN_INFO "md:     L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
1394                 sb->level, sb->size, sb->nr_disks, sb->raid_disks,
1395                 sb->md_minor, sb->layout, sb->chunk_size);
1396         printk(KERN_INFO "md:     UT:%08x ST:%d AD:%d WD:%d"
1397                 " FD:%d SD:%d CSUM:%08x E:%08lx\n",
1398                 sb->utime, sb->state, sb->active_disks, sb->working_disks,
1399                 sb->failed_disks, sb->spare_disks,
1400                 sb->sb_csum, (unsigned long)sb->events_lo);
1401
1402         printk(KERN_INFO);
1403         for (i = 0; i < MD_SB_DISKS; i++) {
1404                 mdp_disk_t *desc;
1405
1406                 desc = sb->disks + i;
1407                 if (desc->number || desc->major || desc->minor ||
1408                     desc->raid_disk || (desc->state && (desc->state != 4))) {
1409                         printk("     D %2d: ", i);
1410                         print_desc(desc);
1411                 }
1412         }
1413         printk(KERN_INFO "md:     THIS: ");
1414         print_desc(&sb->this_disk);
1415
1416 }
1417
1418 static void print_rdev(mdk_rdev_t *rdev)
1419 {
1420         char b[BDEVNAME_SIZE];
1421         printk(KERN_INFO "md: rdev %s, SZ:%08llu F:%d S:%d DN:%u\n",
1422                 bdevname(rdev->bdev,b), (unsigned long long)rdev->size,
1423                 test_bit(Faulty, &rdev->flags), test_bit(In_sync, &rdev->flags),
1424                 rdev->desc_nr);
1425         if (rdev->sb_loaded) {
1426                 printk(KERN_INFO "md: rdev superblock:\n");
1427                 print_sb((mdp_super_t*)page_address(rdev->sb_page));
1428         } else
1429                 printk(KERN_INFO "md: no rdev superblock!\n");
1430 }
1431
1432 void md_print_devices(void)
1433 {
1434         struct list_head *tmp, *tmp2;
1435         mdk_rdev_t *rdev;
1436         mddev_t *mddev;
1437         char b[BDEVNAME_SIZE];
1438
1439         printk("\n");
1440         printk("md:     **********************************\n");
1441         printk("md:     * <COMPLETE RAID STATE PRINTOUT> *\n");
1442         printk("md:     **********************************\n");
1443         ITERATE_MDDEV(mddev,tmp) {
1444
1445                 if (mddev->bitmap)
1446                         bitmap_print_sb(mddev->bitmap);
1447                 else
1448                         printk("%s: ", mdname(mddev));
1449                 ITERATE_RDEV(mddev,rdev,tmp2)
1450                         printk("<%s>", bdevname(rdev->bdev,b));
1451                 printk("\n");
1452
1453                 ITERATE_RDEV(mddev,rdev,tmp2)
1454                         print_rdev(rdev);
1455         }
1456         printk("md:     **********************************\n");
1457         printk("\n");
1458 }
1459
1460
1461 static void sync_sbs(mddev_t * mddev)
1462 {
1463         mdk_rdev_t *rdev;
1464         struct list_head *tmp;
1465
1466         ITERATE_RDEV(mddev,rdev,tmp) {
1467                 super_types[mddev->major_version].
1468                         sync_super(mddev, rdev);
1469                 rdev->sb_loaded = 1;
1470         }
1471 }
1472
1473 static void md_update_sb(mddev_t * mddev)
1474 {
1475         int err;
1476         struct list_head *tmp;
1477         mdk_rdev_t *rdev;
1478         int sync_req;
1479
1480 repeat:
1481         spin_lock_irq(&mddev->write_lock);
1482         sync_req = mddev->in_sync;
1483         mddev->utime = get_seconds();
1484         mddev->events ++;
1485
1486         if (!mddev->events) {
1487                 /*
1488                  * oops, this 64-bit counter should never wrap.
1489                  * Either we are in around ~1 trillion A.C., assuming
1490                  * 1 reboot per second, or we have a bug:
1491                  */
1492                 MD_BUG();
1493                 mddev->events --;
1494         }
1495         mddev->sb_dirty = 2;
1496         sync_sbs(mddev);
1497
1498         /*
1499          * do not write anything to disk if using
1500          * nonpersistent superblocks
1501          */
1502         if (!mddev->persistent) {
1503                 mddev->sb_dirty = 0;
1504                 spin_unlock_irq(&mddev->write_lock);
1505                 wake_up(&mddev->sb_wait);
1506                 return;
1507         }
1508         spin_unlock_irq(&mddev->write_lock);
1509
1510         dprintk(KERN_INFO
1511                 "md: updating %s RAID superblock on device (in sync %d)\n",
1512                 mdname(mddev),mddev->in_sync);
1513
1514         err = bitmap_update_sb(mddev->bitmap);
1515         ITERATE_RDEV(mddev,rdev,tmp) {
1516                 char b[BDEVNAME_SIZE];
1517                 dprintk(KERN_INFO "md: ");
1518                 if (test_bit(Faulty, &rdev->flags))
1519                         dprintk("(skipping faulty ");
1520
1521                 dprintk("%s ", bdevname(rdev->bdev,b));
1522                 if (!test_bit(Faulty, &rdev->flags)) {
1523                         md_super_write(mddev,rdev,
1524                                        rdev->sb_offset<<1, rdev->sb_size,
1525                                        rdev->sb_page);
1526                         dprintk(KERN_INFO "(write) %s's sb offset: %llu\n",
1527                                 bdevname(rdev->bdev,b),
1528                                 (unsigned long long)rdev->sb_offset);
1529
1530                 } else
1531                         dprintk(")\n");
1532                 if (mddev->level == LEVEL_MULTIPATH)
1533                         /* only need to write one superblock... */
1534                         break;
1535         }
1536         md_super_wait(mddev);
1537         /* if there was a failure, sb_dirty was set to 1, and we re-write super */
1538
1539         spin_lock_irq(&mddev->write_lock);
1540         if (mddev->in_sync != sync_req|| mddev->sb_dirty == 1) {
1541                 /* have to write it out again */
1542                 spin_unlock_irq(&mddev->write_lock);
1543                 goto repeat;
1544         }
1545         mddev->sb_dirty = 0;
1546         spin_unlock_irq(&mddev->write_lock);
1547         wake_up(&mddev->sb_wait);
1548
1549 }
1550
1551 /* words written to sysfs files may, or my not, be \n terminated.
1552  * We want to accept with case. For this we use cmd_match.
1553  */
1554 static int cmd_match(const char *cmd, const char *str)
1555 {
1556         /* See if cmd, written into a sysfs file, matches
1557          * str.  They must either be the same, or cmd can
1558          * have a trailing newline
1559          */
1560         while (*cmd && *str && *cmd == *str) {
1561                 cmd++;
1562                 str++;
1563         }
1564         if (*cmd == '\n')
1565                 cmd++;
1566         if (*str || *cmd)
1567                 return 0;
1568         return 1;
1569 }
1570
1571 struct rdev_sysfs_entry {
1572         struct attribute attr;
1573         ssize_t (*show)(mdk_rdev_t *, char *);
1574         ssize_t (*store)(mdk_rdev_t *, const char *, size_t);
1575 };
1576
1577 static ssize_t
1578 state_show(mdk_rdev_t *rdev, char *page)
1579 {
1580         char *sep = "";
1581         int len=0;
1582
1583         if (test_bit(Faulty, &rdev->flags)) {
1584                 len+= sprintf(page+len, "%sfaulty",sep);
1585                 sep = ",";
1586         }
1587         if (test_bit(In_sync, &rdev->flags)) {
1588                 len += sprintf(page+len, "%sin_sync",sep);
1589                 sep = ",";
1590         }
1591         if (!test_bit(Faulty, &rdev->flags) &&
1592             !test_bit(In_sync, &rdev->flags)) {
1593                 len += sprintf(page+len, "%sspare", sep);
1594                 sep = ",";
1595         }
1596         return len+sprintf(page+len, "\n");
1597 }
1598
1599 static struct rdev_sysfs_entry
1600 rdev_state = __ATTR_RO(state);
1601
1602 static ssize_t
1603 super_show(mdk_rdev_t *rdev, char *page)
1604 {
1605         if (rdev->sb_loaded && rdev->sb_size) {
1606                 memcpy(page, page_address(rdev->sb_page), rdev->sb_size);
1607                 return rdev->sb_size;
1608         } else
1609                 return 0;
1610 }
1611 static struct rdev_sysfs_entry rdev_super = __ATTR_RO(super);
1612
1613 static ssize_t
1614 errors_show(mdk_rdev_t *rdev, char *page)
1615 {
1616         return sprintf(page, "%d\n", atomic_read(&rdev->corrected_errors));
1617 }
1618
1619 static ssize_t
1620 errors_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1621 {
1622         char *e;
1623         unsigned long n = simple_strtoul(buf, &e, 10);
1624         if (*buf && (*e == 0 || *e == '\n')) {
1625                 atomic_set(&rdev->corrected_errors, n);
1626                 return len;
1627         }
1628         return -EINVAL;
1629 }
1630 static struct rdev_sysfs_entry rdev_errors =
1631 __ATTR(errors, 0644, errors_show, errors_store);
1632
1633 static ssize_t
1634 slot_show(mdk_rdev_t *rdev, char *page)
1635 {
1636         if (rdev->raid_disk < 0)
1637                 return sprintf(page, "none\n");
1638         else
1639                 return sprintf(page, "%d\n", rdev->raid_disk);
1640 }
1641
1642 static ssize_t
1643 slot_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1644 {
1645         char *e;
1646         int slot = simple_strtoul(buf, &e, 10);
1647         if (strncmp(buf, "none", 4)==0)
1648                 slot = -1;
1649         else if (e==buf || (*e && *e!= '\n'))
1650                 return -EINVAL;
1651         if (rdev->mddev->pers)
1652                 /* Cannot set slot in active array (yet) */
1653                 return -EBUSY;
1654         if (slot >= rdev->mddev->raid_disks)
1655                 return -ENOSPC;
1656         rdev->raid_disk = slot;
1657         /* assume it is working */
1658         rdev->flags = 0;
1659         set_bit(In_sync, &rdev->flags);
1660         return len;
1661 }
1662
1663
1664 static struct rdev_sysfs_entry rdev_slot =
1665 __ATTR(slot, 0644, slot_show, slot_store);
1666
1667 static ssize_t
1668 offset_show(mdk_rdev_t *rdev, char *page)
1669 {
1670         return sprintf(page, "%llu\n", rdev->data_offset);
1671 }
1672
1673 static ssize_t
1674 offset_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1675 {
1676         char *e;
1677         unsigned long long offset = simple_strtoull(buf, &e, 10);
1678         if (e==buf || (*e && *e != '\n'))
1679                 return -EINVAL;
1680         if (rdev->mddev->pers)
1681                 return -EBUSY;
1682         rdev->data_offset = offset;
1683         return len;
1684 }
1685
1686 static struct rdev_sysfs_entry rdev_offset =
1687 __ATTR(offset, 0644, offset_show, offset_store);
1688
1689 static struct attribute *rdev_default_attrs[] = {
1690         &rdev_state.attr,
1691         &rdev_super.attr,
1692         &rdev_errors.attr,
1693         &rdev_slot.attr,
1694         &rdev_offset.attr,
1695         NULL,
1696 };
1697 static ssize_t
1698 rdev_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
1699 {
1700         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
1701         mdk_rdev_t *rdev = container_of(kobj, mdk_rdev_t, kobj);
1702
1703         if (!entry->show)
1704                 return -EIO;
1705         return entry->show(rdev, page);
1706 }
1707
1708 static ssize_t
1709 rdev_attr_store(struct kobject *kobj, struct attribute *attr,
1710               const char *page, size_t length)
1711 {
1712         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
1713         mdk_rdev_t *rdev = container_of(kobj, mdk_rdev_t, kobj);
1714
1715         if (!entry->store)
1716                 return -EIO;
1717         return entry->store(rdev, page, length);
1718 }
1719
1720 static void rdev_free(struct kobject *ko)
1721 {
1722         mdk_rdev_t *rdev = container_of(ko, mdk_rdev_t, kobj);
1723         kfree(rdev);
1724 }
1725 static struct sysfs_ops rdev_sysfs_ops = {
1726         .show           = rdev_attr_show,
1727         .store          = rdev_attr_store,
1728 };
1729 static struct kobj_type rdev_ktype = {
1730         .release        = rdev_free,
1731         .sysfs_ops      = &rdev_sysfs_ops,
1732         .default_attrs  = rdev_default_attrs,
1733 };
1734
1735 /*
1736  * Import a device. If 'super_format' >= 0, then sanity check the superblock
1737  *
1738  * mark the device faulty if:
1739  *
1740  *   - the device is nonexistent (zero size)
1741  *   - the device has no valid superblock
1742  *
1743  * a faulty rdev _never_ has rdev->sb set.
1744  */
1745 static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_minor)
1746 {
1747         char b[BDEVNAME_SIZE];
1748         int err;
1749         mdk_rdev_t *rdev;
1750         sector_t size;
1751
1752         rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
1753         if (!rdev) {
1754                 printk(KERN_ERR "md: could not alloc mem for new device!\n");
1755                 return ERR_PTR(-ENOMEM);
1756         }
1757
1758         if ((err = alloc_disk_sb(rdev)))
1759                 goto abort_free;
1760
1761         err = lock_rdev(rdev, newdev);
1762         if (err)
1763                 goto abort_free;
1764
1765         rdev->kobj.parent = NULL;
1766         rdev->kobj.ktype = &rdev_ktype;
1767         kobject_init(&rdev->kobj);
1768
1769         rdev->desc_nr = -1;
1770         rdev->flags = 0;
1771         rdev->data_offset = 0;
1772         atomic_set(&rdev->nr_pending, 0);
1773         atomic_set(&rdev->read_errors, 0);
1774         atomic_set(&rdev->corrected_errors, 0);
1775
1776         size = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
1777         if (!size) {
1778                 printk(KERN_WARNING
1779                         "md: %s has zero or unknown size, marking faulty!\n",
1780                         bdevname(rdev->bdev,b));
1781                 err = -EINVAL;
1782                 goto abort_free;
1783         }
1784
1785         if (super_format >= 0) {
1786                 err = super_types[super_format].
1787                         load_super(rdev, NULL, super_minor);
1788                 if (err == -EINVAL) {
1789                         printk(KERN_WARNING
1790                                 "md: %s has invalid sb, not importing!\n",
1791                                 bdevname(rdev->bdev,b));
1792                         goto abort_free;
1793                 }
1794                 if (err < 0) {
1795                         printk(KERN_WARNING
1796                                 "md: could not read %s's sb, not importing!\n",
1797                                 bdevname(rdev->bdev,b));
1798                         goto abort_free;
1799                 }
1800         }
1801         INIT_LIST_HEAD(&rdev->same_set);
1802
1803         return rdev;
1804
1805 abort_free:
1806         if (rdev->sb_page) {
1807                 if (rdev->bdev)
1808                         unlock_rdev(rdev);
1809                 free_disk_sb(rdev);
1810         }
1811         kfree(rdev);
1812         return ERR_PTR(err);
1813 }
1814
1815 /*
1816  * Check a full RAID array for plausibility
1817  */
1818
1819
1820 static void analyze_sbs(mddev_t * mddev)
1821 {
1822         int i;
1823         struct list_head *tmp;
1824         mdk_rdev_t *rdev, *freshest;
1825         char b[BDEVNAME_SIZE];
1826
1827         freshest = NULL;
1828         ITERATE_RDEV(mddev,rdev,tmp)
1829                 switch (super_types[mddev->major_version].
1830                         load_super(rdev, freshest, mddev->minor_version)) {
1831                 case 1:
1832                         freshest = rdev;
1833                         break;
1834                 case 0:
1835                         break;
1836                 default:
1837                         printk( KERN_ERR \
1838                                 "md: fatal superblock inconsistency in %s"
1839                                 " -- removing from array\n",
1840                                 bdevname(rdev->bdev,b));
1841                         kick_rdev_from_array(rdev);
1842                 }
1843
1844
1845         super_types[mddev->major_version].
1846                 validate_super(mddev, freshest);
1847
1848         i = 0;
1849         ITERATE_RDEV(mddev,rdev,tmp) {
1850                 if (rdev != freshest)
1851                         if (super_types[mddev->major_version].
1852                             validate_super(mddev, rdev)) {
1853                                 printk(KERN_WARNING "md: kicking non-fresh %s"
1854                                         " from array!\n",
1855                                         bdevname(rdev->bdev,b));
1856                                 kick_rdev_from_array(rdev);
1857                                 continue;
1858                         }
1859                 if (mddev->level == LEVEL_MULTIPATH) {
1860                         rdev->desc_nr = i++;
1861                         rdev->raid_disk = rdev->desc_nr;
1862                         set_bit(In_sync, &rdev->flags);
1863                 }
1864         }
1865
1866
1867
1868         if (mddev->recovery_cp != MaxSector &&
1869             mddev->level >= 1)
1870                 printk(KERN_ERR "md: %s: raid array is not clean"
1871                        " -- starting background reconstruction\n",
1872                        mdname(mddev));
1873
1874 }
1875
1876 static ssize_t
1877 level_show(mddev_t *mddev, char *page)
1878 {
1879         struct mdk_personality *p = mddev->pers;
1880         if (p)
1881                 return sprintf(page, "%s\n", p->name);
1882         else if (mddev->clevel[0])
1883                 return sprintf(page, "%s\n", mddev->clevel);
1884         else if (mddev->level != LEVEL_NONE)
1885                 return sprintf(page, "%d\n", mddev->level);
1886         else
1887                 return 0;
1888 }
1889
1890 static ssize_t
1891 level_store(mddev_t *mddev, const char *buf, size_t len)
1892 {
1893         int rv = len;
1894         if (mddev->pers)
1895                 return -EBUSY;
1896         if (len == 0)
1897                 return 0;
1898         if (len >= sizeof(mddev->clevel))
1899                 return -ENOSPC;
1900         strncpy(mddev->clevel, buf, len);
1901         if (mddev->clevel[len-1] == '\n')
1902                 len--;
1903         mddev->clevel[len] = 0;
1904         mddev->level = LEVEL_NONE;
1905         return rv;
1906 }
1907
1908 static struct md_sysfs_entry md_level =
1909 __ATTR(level, 0644, level_show, level_store);
1910
1911 static ssize_t
1912 raid_disks_show(mddev_t *mddev, char *page)
1913 {
1914         if (mddev->raid_disks == 0)
1915                 return 0;
1916         return sprintf(page, "%d\n", mddev->raid_disks);
1917 }
1918
1919 static int update_raid_disks(mddev_t *mddev, int raid_disks);
1920
1921 static ssize_t
1922 raid_disks_store(mddev_t *mddev, const char *buf, size_t len)
1923 {
1924         /* can only set raid_disks if array is not yet active */
1925         char *e;
1926         int rv = 0;
1927         unsigned long n = simple_strtoul(buf, &e, 10);
1928
1929         if (!*buf || (*e && *e != '\n'))
1930                 return -EINVAL;
1931
1932         if (mddev->pers)
1933                 rv = update_raid_disks(mddev, n);
1934         else
1935                 mddev->raid_disks = n;
1936         return rv ? rv : len;
1937 }
1938 static struct md_sysfs_entry md_raid_disks =
1939 __ATTR(raid_disks, 0644, raid_disks_show, raid_disks_store);
1940
1941 static ssize_t
1942 chunk_size_show(mddev_t *mddev, char *page)
1943 {
1944         return sprintf(page, "%d\n", mddev->chunk_size);
1945 }
1946
1947 static ssize_t
1948 chunk_size_store(mddev_t *mddev, const char *buf, size_t len)
1949 {
1950         /* can only set chunk_size if array is not yet active */
1951         char *e;
1952         unsigned long n = simple_strtoul(buf, &e, 10);
1953
1954         if (mddev->pers)
1955                 return -EBUSY;
1956         if (!*buf || (*e && *e != '\n'))
1957                 return -EINVAL;
1958
1959         mddev->chunk_size = n;
1960         return len;
1961 }
1962 static struct md_sysfs_entry md_chunk_size =
1963 __ATTR(chunk_size, 0644, chunk_size_show, chunk_size_store);
1964
1965
1966 static ssize_t
1967 size_show(mddev_t *mddev, char *page)
1968 {
1969         return sprintf(page, "%llu\n", (unsigned long long)mddev->size);
1970 }
1971
1972 static int update_size(mddev_t *mddev, unsigned long size);
1973
1974 static ssize_t
1975 size_store(mddev_t *mddev, const char *buf, size_t len)
1976 {
1977         /* If array is inactive, we can reduce the component size, but
1978          * not increase it (except from 0).
1979          * If array is active, we can try an on-line resize
1980          */
1981         char *e;
1982         int err = 0;
1983         unsigned long long size = simple_strtoull(buf, &e, 10);
1984         if (!*buf || *buf == '\n' ||
1985             (*e && *e != '\n'))
1986                 return -EINVAL;
1987
1988         if (mddev->pers) {
1989                 err = update_size(mddev, size);
1990                 md_update_sb(mddev);
1991         } else {
1992                 if (mddev->size == 0 ||
1993                     mddev->size > size)
1994                         mddev->size = size;
1995                 else
1996                         err = -ENOSPC;
1997         }
1998         return err ? err : len;
1999 }
2000
2001 static struct md_sysfs_entry md_size =
2002 __ATTR(component_size, 0644, size_show, size_store);
2003
2004
2005 /* Metdata version.
2006  * This is either 'none' for arrays with externally managed metadata,
2007  * or N.M for internally known formats
2008  */
2009 static ssize_t
2010 metadata_show(mddev_t *mddev, char *page)
2011 {
2012         if (mddev->persistent)
2013                 return sprintf(page, "%d.%d\n",
2014                                mddev->major_version, mddev->minor_version);
2015         else
2016                 return sprintf(page, "none\n");
2017 }
2018
2019 static ssize_t
2020 metadata_store(mddev_t *mddev, const char *buf, size_t len)
2021 {
2022         int major, minor;
2023         char *e;
2024         if (!list_empty(&mddev->disks))
2025                 return -EBUSY;
2026
2027         if (cmd_match(buf, "none")) {
2028                 mddev->persistent = 0;
2029                 mddev->major_version = 0;
2030                 mddev->minor_version = 90;
2031                 return len;
2032         }
2033         major = simple_strtoul(buf, &e, 10);
2034         if (e==buf || *e != '.')
2035                 return -EINVAL;
2036         buf = e+1;
2037         minor = simple_strtoul(buf, &e, 10);
2038         if (e==buf || *e != '\n')
2039                 return -EINVAL;
2040         if (major >= sizeof(super_types)/sizeof(super_types[0]) ||
2041             super_types[major].name == NULL)
2042                 return -ENOENT;
2043         mddev->major_version = major;
2044         mddev->minor_version = minor;
2045         mddev->persistent = 1;
2046         return len;
2047 }
2048
2049 static struct md_sysfs_entry md_metadata =
2050 __ATTR(metadata_version, 0644, metadata_show, metadata_store);
2051
2052 static ssize_t
2053 action_show(mddev_t *mddev, char *page)
2054 {
2055         char *type = "idle";
2056         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
2057             test_bit(MD_RECOVERY_NEEDED, &mddev->recovery)) {
2058                 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
2059                         if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2060                                 type = "resync";
2061                         else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
2062                                 type = "check";
2063                         else
2064                                 type = "repair";
2065                 } else
2066                         type = "recover";
2067         }
2068         return sprintf(page, "%s\n", type);
2069 }
2070
2071 static ssize_t
2072 action_store(mddev_t *mddev, const char *page, size_t len)
2073 {
2074         if (!mddev->pers || !mddev->pers->sync_request)
2075                 return -EINVAL;
2076
2077         if (cmd_match(page, "idle")) {
2078                 if (mddev->sync_thread) {
2079                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2080                         md_unregister_thread(mddev->sync_thread);
2081                         mddev->sync_thread = NULL;
2082                         mddev->recovery = 0;
2083                 }
2084         } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
2085                    test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
2086                 return -EBUSY;
2087         else if (cmd_match(page, "resync") || cmd_match(page, "recover"))
2088                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2089         else {
2090                 if (cmd_match(page, "check"))
2091                         set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
2092                 else if (cmd_match(page, "repair"))
2093                         return -EINVAL;
2094                 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
2095                 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
2096         }
2097         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2098         md_wakeup_thread(mddev->thread);
2099         return len;
2100 }
2101
2102 static ssize_t
2103 mismatch_cnt_show(mddev_t *mddev, char *page)
2104 {
2105         return sprintf(page, "%llu\n",
2106                        (unsigned long long) mddev->resync_mismatches);
2107 }
2108
2109 static struct md_sysfs_entry
2110 md_scan_mode = __ATTR(sync_action, S_IRUGO|S_IWUSR, action_show, action_store);
2111
2112
2113 static struct md_sysfs_entry
2114 md_mismatches = __ATTR_RO(mismatch_cnt);
2115
2116 static struct attribute *md_default_attrs[] = {
2117         &md_level.attr,
2118         &md_raid_disks.attr,
2119         &md_chunk_size.attr,
2120         &md_size.attr,
2121         &md_metadata.attr,
2122         NULL,
2123 };
2124
2125 static struct attribute *md_redundancy_attrs[] = {
2126         &md_scan_mode.attr,
2127         &md_mismatches.attr,
2128         NULL,
2129 };
2130 static struct attribute_group md_redundancy_group = {
2131         .name = NULL,
2132         .attrs = md_redundancy_attrs,
2133 };
2134
2135
2136 static ssize_t
2137 md_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
2138 {
2139         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
2140         mddev_t *mddev = container_of(kobj, struct mddev_s, kobj);
2141         ssize_t rv;
2142
2143         if (!entry->show)
2144                 return -EIO;
2145         mddev_lock(mddev);
2146         rv = entry->show(mddev, page);
2147         mddev_unlock(mddev);
2148         return rv;
2149 }
2150
2151 static ssize_t
2152 md_attr_store(struct kobject *kobj, struct attribute *attr,
2153               const char *page, size_t length)
2154 {
2155         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
2156         mddev_t *mddev = container_of(kobj, struct mddev_s, kobj);
2157         ssize_t rv;
2158
2159         if (!entry->store)
2160                 return -EIO;
2161         mddev_lock(mddev);
2162         rv = entry->store(mddev, page, length);
2163         mddev_unlock(mddev);
2164         return rv;
2165 }
2166
2167 static void md_free(struct kobject *ko)
2168 {
2169         mddev_t *mddev = container_of(ko, mddev_t, kobj);
2170         kfree(mddev);
2171 }
2172
2173 static struct sysfs_ops md_sysfs_ops = {
2174         .show   = md_attr_show,
2175         .store  = md_attr_store,
2176 };
2177 static struct kobj_type md_ktype = {
2178         .release        = md_free,
2179         .sysfs_ops      = &md_sysfs_ops,
2180         .default_attrs  = md_default_attrs,
2181 };
2182
2183 int mdp_major = 0;
2184
2185 static struct kobject *md_probe(dev_t dev, int *part, void *data)
2186 {
2187         static DECLARE_MUTEX(disks_sem);
2188         mddev_t *mddev = mddev_find(dev);
2189         struct gendisk *disk;
2190         int partitioned = (MAJOR(dev) != MD_MAJOR);
2191         int shift = partitioned ? MdpMinorShift : 0;
2192         int unit = MINOR(dev) >> shift;
2193
2194         if (!mddev)
2195                 return NULL;
2196
2197         down(&disks_sem);
2198         if (mddev->gendisk) {
2199                 up(&disks_sem);
2200                 mddev_put(mddev);
2201                 return NULL;
2202         }
2203         disk = alloc_disk(1 << shift);
2204         if (!disk) {
2205                 up(&disks_sem);
2206                 mddev_put(mddev);
2207                 return NULL;
2208         }
2209         disk->major = MAJOR(dev);
2210         disk->first_minor = unit << shift;
2211         if (partitioned) {
2212                 sprintf(disk->disk_name, "md_d%d", unit);
2213                 sprintf(disk->devfs_name, "md/d%d", unit);
2214         } else {
2215                 sprintf(disk->disk_name, "md%d", unit);
2216                 sprintf(disk->devfs_name, "md/%d", unit);
2217         }
2218         disk->fops = &md_fops;
2219         disk->private_data = mddev;
2220         disk->queue = mddev->queue;
2221         add_disk(disk);
2222         mddev->gendisk = disk;
2223         up(&disks_sem);
2224         mddev->kobj.parent = &disk->kobj;
2225         mddev->kobj.k_name = NULL;
2226         snprintf(mddev->kobj.name, KOBJ_NAME_LEN, "%s", "md");
2227         mddev->kobj.ktype = &md_ktype;
2228         kobject_register(&mddev->kobj);
2229         return NULL;
2230 }
2231
2232 void md_wakeup_thread(mdk_thread_t *thread);
2233
2234 static void md_safemode_timeout(unsigned long data)
2235 {
2236         mddev_t *mddev = (mddev_t *) data;
2237
2238         mddev->safemode = 1;
2239         md_wakeup_thread(mddev->thread);
2240 }
2241
2242 static int start_dirty_degraded;
2243
2244 static int do_md_run(mddev_t * mddev)
2245 {
2246         int err;
2247         int chunk_size;
2248         struct list_head *tmp;
2249         mdk_rdev_t *rdev;
2250         struct gendisk *disk;
2251         struct mdk_personality *pers;
2252         char b[BDEVNAME_SIZE];
2253
2254         if (list_empty(&mddev->disks))
2255                 /* cannot run an array with no devices.. */
2256                 return -EINVAL;
2257
2258         if (mddev->pers)
2259                 return -EBUSY;
2260
2261         /*
2262          * Analyze all RAID superblock(s)
2263          */
2264         if (!mddev->raid_disks)
2265                 analyze_sbs(mddev);
2266
2267         chunk_size = mddev->chunk_size;
2268
2269         if (chunk_size) {
2270                 if (chunk_size > MAX_CHUNK_SIZE) {
2271                         printk(KERN_ERR "too big chunk_size: %d > %d\n",
2272                                 chunk_size, MAX_CHUNK_SIZE);
2273                         return -EINVAL;
2274                 }
2275                 /*
2276                  * chunk-size has to be a power of 2 and multiples of PAGE_SIZE
2277                  */
2278                 if ( (1 << ffz(~chunk_size)) != chunk_size) {
2279                         printk(KERN_ERR "chunk_size of %d not valid\n", chunk_size);
2280                         return -EINVAL;
2281                 }
2282                 if (chunk_size < PAGE_SIZE) {
2283                         printk(KERN_ERR "too small chunk_size: %d < %ld\n",
2284                                 chunk_size, PAGE_SIZE);
2285                         return -EINVAL;
2286                 }
2287
2288                 /* devices must have minimum size of one chunk */
2289                 ITERATE_RDEV(mddev,rdev,tmp) {
2290                         if (test_bit(Faulty, &rdev->flags))
2291                                 continue;
2292                         if (rdev->size < chunk_size / 1024) {
2293                                 printk(KERN_WARNING
2294                                         "md: Dev %s smaller than chunk_size:"
2295                                         " %lluk < %dk\n",
2296                                         bdevname(rdev->bdev,b),
2297                                         (unsigned long long)rdev->size,
2298                                         chunk_size / 1024);
2299                                 return -EINVAL;
2300                         }
2301                 }
2302         }
2303
2304 #ifdef CONFIG_KMOD
2305         if (mddev->level != LEVEL_NONE)
2306                 request_module("md-level-%d", mddev->level);
2307         else if (mddev->clevel[0])
2308                 request_module("md-%s", mddev->clevel);
2309 #endif
2310
2311         /*
2312          * Drop all container device buffers, from now on
2313          * the only valid external interface is through the md
2314          * device.
2315          * Also find largest hardsector size
2316          */
2317         ITERATE_RDEV(mddev,rdev,tmp) {
2318                 if (test_bit(Faulty, &rdev->flags))
2319                         continue;
2320                 sync_blockdev(rdev->bdev);
2321                 invalidate_bdev(rdev->bdev, 0);
2322         }
2323
2324         md_probe(mddev->unit, NULL, NULL);
2325         disk = mddev->gendisk;
2326         if (!disk)
2327                 return -ENOMEM;
2328
2329         spin_lock(&pers_lock);
2330         pers = find_pers(mddev->level, mddev->clevel);
2331         if (!pers || !try_module_get(pers->owner)) {
2332                 spin_unlock(&pers_lock);
2333                 if (mddev->level != LEVEL_NONE)
2334                         printk(KERN_WARNING "md: personality for level %d is not loaded!\n",
2335                                mddev->level);
2336                 else
2337                         printk(KERN_WARNING "md: personality for level %s is not loaded!\n",
2338                                mddev->clevel);
2339                 return -EINVAL;
2340         }
2341         mddev->pers = pers;
2342         spin_unlock(&pers_lock);
2343         mddev->level = pers->level;
2344         strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
2345
2346         mddev->recovery = 0;
2347         mddev->resync_max_sectors = mddev->size << 1; /* may be over-ridden by personality */
2348         mddev->barriers_work = 1;
2349         mddev->ok_start_degraded = start_dirty_degraded;
2350
2351         if (start_readonly)
2352                 mddev->ro = 2; /* read-only, but switch on first write */
2353
2354         err = mddev->pers->run(mddev);
2355         if (!err && mddev->pers->sync_request) {
2356                 err = bitmap_create(mddev);
2357                 if (err) {
2358                         printk(KERN_ERR "%s: failed to create bitmap (%d)\n",
2359                                mdname(mddev), err);
2360                         mddev->pers->stop(mddev);
2361                 }
2362         }
2363         if (err) {
2364                 printk(KERN_ERR "md: pers->run() failed ...\n");
2365                 module_put(mddev->pers->owner);
2366                 mddev->pers = NULL;
2367                 bitmap_destroy(mddev);
2368                 return err;
2369         }
2370         if (mddev->pers->sync_request)
2371                 sysfs_create_group(&mddev->kobj, &md_redundancy_group);
2372         else if (mddev->ro == 2) /* auto-readonly not meaningful */
2373                 mddev->ro = 0;
2374
2375         atomic_set(&mddev->writes_pending,0);
2376         mddev->safemode = 0;
2377         mddev->safemode_timer.function = md_safemode_timeout;
2378         mddev->safemode_timer.data = (unsigned long) mddev;
2379         mddev->safemode_delay = (20 * HZ)/1000 +1; /* 20 msec delay */
2380         mddev->in_sync = 1;
2381
2382         ITERATE_RDEV(mddev,rdev,tmp)
2383                 if (rdev->raid_disk >= 0) {
2384                         char nm[20];
2385                         sprintf(nm, "rd%d", rdev->raid_disk);
2386                         sysfs_create_link(&mddev->kobj, &rdev->kobj, nm);
2387                 }
2388
2389         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2390         md_wakeup_thread(mddev->thread);
2391
2392         if (mddev->sb_dirty)
2393                 md_update_sb(mddev);
2394
2395         set_capacity(disk, mddev->array_size<<1);
2396
2397         /* If we call blk_queue_make_request here, it will
2398          * re-initialise max_sectors etc which may have been
2399          * refined inside -> run.  So just set the bits we need to set.
2400          * Most initialisation happended when we called
2401          * blk_queue_make_request(..., md_fail_request)
2402          * earlier.
2403          */
2404         mddev->queue->queuedata = mddev;
2405         mddev->queue->make_request_fn = mddev->pers->make_request;
2406
2407         mddev->changed = 1;
2408         md_new_event(mddev);
2409         return 0;
2410 }
2411
2412 static int restart_array(mddev_t *mddev)
2413 {
2414         struct gendisk *disk = mddev->gendisk;
2415         int err;
2416
2417         /*
2418          * Complain if it has no devices
2419          */
2420         err = -ENXIO;
2421         if (list_empty(&mddev->disks))
2422                 goto out;
2423
2424         if (mddev->pers) {
2425                 err = -EBUSY;
2426                 if (!mddev->ro)
2427                         goto out;
2428
2429                 mddev->safemode = 0;
2430                 mddev->ro = 0;
2431                 set_disk_ro(disk, 0);
2432
2433                 printk(KERN_INFO "md: %s switched to read-write mode.\n",
2434                         mdname(mddev));
2435                 /*
2436                  * Kick recovery or resync if necessary
2437                  */
2438                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2439                 md_wakeup_thread(mddev->thread);
2440                 err = 0;
2441         } else {
2442                 printk(KERN_ERR "md: %s has no personality assigned.\n",
2443                         mdname(mddev));
2444                 err = -EINVAL;
2445         }
2446
2447 out:
2448         return err;
2449 }
2450
2451 static int do_md_stop(mddev_t * mddev, int ro)
2452 {
2453         int err = 0;
2454         struct gendisk *disk = mddev->gendisk;
2455
2456         if (mddev->pers) {
2457                 if (atomic_read(&mddev->active)>2) {
2458                         printk("md: %s still in use.\n",mdname(mddev));
2459                         return -EBUSY;
2460                 }
2461
2462                 if (mddev->sync_thread) {
2463                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2464                         md_unregister_thread(mddev->sync_thread);
2465                         mddev->sync_thread = NULL;
2466                 }
2467
2468                 del_timer_sync(&mddev->safemode_timer);
2469
2470                 invalidate_partition(disk, 0);
2471
2472                 if (ro) {
2473                         err  = -ENXIO;
2474                         if (mddev->ro==1)
2475                                 goto out;
2476                         mddev->ro = 1;
2477                 } else {
2478                         bitmap_flush(mddev);
2479                         md_super_wait(mddev);
2480                         if (mddev->ro)
2481                                 set_disk_ro(disk, 0);
2482                         blk_queue_make_request(mddev->queue, md_fail_request);
2483                         mddev->pers->stop(mddev);
2484                         if (mddev->pers->sync_request)
2485                                 sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
2486
2487                         module_put(mddev->pers->owner);
2488                         mddev->pers = NULL;
2489                         if (mddev->ro)
2490                                 mddev->ro = 0;
2491                 }
2492                 if (!mddev->in_sync) {
2493                         /* mark array as shutdown cleanly */
2494                         mddev->in_sync = 1;
2495                         md_update_sb(mddev);
2496                 }
2497                 if (ro)
2498                         set_disk_ro(disk, 1);
2499         }
2500
2501         bitmap_destroy(mddev);
2502         if (mddev->bitmap_file) {
2503                 atomic_set(&mddev->bitmap_file->f_dentry->d_inode->i_writecount, 1);
2504                 fput(mddev->bitmap_file);
2505                 mddev->bitmap_file = NULL;
2506         }
2507         mddev->bitmap_offset = 0;
2508
2509         /*
2510          * Free resources if final stop
2511          */
2512         if (!ro) {
2513                 mdk_rdev_t *rdev;
2514                 struct list_head *tmp;
2515                 struct gendisk *disk;
2516                 printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
2517
2518                 ITERATE_RDEV(mddev,rdev,tmp)
2519                         if (rdev->raid_disk >= 0) {
2520                                 char nm[20];
2521                                 sprintf(nm, "rd%d", rdev->raid_disk);
2522                                 sysfs_remove_link(&mddev->kobj, nm);
2523                         }
2524
2525                 export_array(mddev);
2526
2527                 mddev->array_size = 0;
2528                 disk = mddev->gendisk;
2529                 if (disk)
2530                         set_capacity(disk, 0);
2531                 mddev->changed = 1;
2532         } else
2533                 printk(KERN_INFO "md: %s switched to read-only mode.\n",
2534                         mdname(mddev));
2535         err = 0;
2536         md_new_event(mddev);
2537 out:
2538         return err;
2539 }
2540
2541 static void autorun_array(mddev_t *mddev)
2542 {
2543         mdk_rdev_t *rdev;
2544         struct list_head *tmp;
2545         int err;
2546
2547         if (list_empty(&mddev->disks))
2548                 return;
2549
2550         printk(KERN_INFO "md: running: ");
2551
2552         ITERATE_RDEV(mddev,rdev,tmp) {
2553                 char b[BDEVNAME_SIZE];
2554                 printk("<%s>", bdevname(rdev->bdev,b));
2555         }
2556         printk("\n");
2557
2558         err = do_md_run (mddev);
2559         if (err) {
2560                 printk(KERN_WARNING "md: do_md_run() returned %d\n", err);
2561                 do_md_stop (mddev, 0);
2562         }
2563 }
2564
2565 /*
2566  * lets try to run arrays based on all disks that have arrived
2567  * until now. (those are in pending_raid_disks)
2568  *
2569  * the method: pick the first pending disk, collect all disks with
2570  * the same UUID, remove all from the pending list and put them into
2571  * the 'same_array' list. Then order this list based on superblock
2572  * update time (freshest comes first), kick out 'old' disks and
2573  * compare superblocks. If everything's fine then run it.
2574  *
2575  * If "unit" is allocated, then bump its reference count
2576  */
2577 static void autorun_devices(int part)
2578 {
2579         struct list_head candidates;
2580         struct list_head *tmp;
2581         mdk_rdev_t *rdev0, *rdev;
2582         mddev_t *mddev;
2583         char b[BDEVNAME_SIZE];
2584
2585         printk(KERN_INFO "md: autorun ...\n");
2586         while (!list_empty(&pending_raid_disks)) {
2587                 dev_t dev;
2588                 rdev0 = list_entry(pending_raid_disks.next,
2589                                          mdk_rdev_t, same_set);
2590
2591                 printk(KERN_INFO "md: considering %s ...\n",
2592                         bdevname(rdev0->bdev,b));
2593                 INIT_LIST_HEAD(&candidates);
2594                 ITERATE_RDEV_PENDING(rdev,tmp)
2595                         if (super_90_load(rdev, rdev0, 0) >= 0) {
2596                                 printk(KERN_INFO "md:  adding %s ...\n",
2597                                         bdevname(rdev->bdev,b));
2598                                 list_move(&rdev->same_set, &candidates);
2599                         }
2600                 /*
2601                  * now we have a set of devices, with all of them having
2602                  * mostly sane superblocks. It's time to allocate the
2603                  * mddev.
2604                  */
2605                 if (rdev0->preferred_minor < 0 || rdev0->preferred_minor >= MAX_MD_DEVS) {
2606                         printk(KERN_INFO "md: unit number in %s is bad: %d\n",
2607                                bdevname(rdev0->bdev, b), rdev0->preferred_minor);
2608                         break;
2609                 }
2610                 if (part)
2611                         dev = MKDEV(mdp_major,
2612                                     rdev0->preferred_minor << MdpMinorShift);
2613                 else
2614                         dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
2615
2616                 md_probe(dev, NULL, NULL);
2617                 mddev = mddev_find(dev);
2618                 if (!mddev) {
2619                         printk(KERN_ERR
2620                                 "md: cannot allocate memory for md drive.\n");
2621                         break;
2622                 }
2623                 if (mddev_lock(mddev))
2624                         printk(KERN_WARNING "md: %s locked, cannot run\n",
2625                                mdname(mddev));
2626                 else if (mddev->raid_disks || mddev->major_version
2627                          || !list_empty(&mddev->disks)) {
2628                         printk(KERN_WARNING
2629                                 "md: %s already running, cannot run %s\n",
2630                                 mdname(mddev), bdevname(rdev0->bdev,b));
2631                         mddev_unlock(mddev);
2632                 } else {
2633                         printk(KERN_INFO "md: created %s\n", mdname(mddev));
2634                         ITERATE_RDEV_GENERIC(candidates,rdev,tmp) {
2635                                 list_del_init(&rdev->same_set);
2636                                 if (bind_rdev_to_array(rdev, mddev))
2637                                         export_rdev(rdev);
2638                         }
2639                         autorun_array(mddev);
2640                         mddev_unlock(mddev);
2641                 }
2642                 /* on success, candidates will be empty, on error
2643                  * it won't...
2644                  */
2645                 ITERATE_RDEV_GENERIC(candidates,rdev,tmp)
2646                         export_rdev(rdev);
2647                 mddev_put(mddev);
2648         }
2649         printk(KERN_INFO "md: ... autorun DONE.\n");
2650 }
2651
2652 /*
2653  * import RAID devices based on one partition
2654  * if possible, the array gets run as well.
2655  */
2656
2657 static int autostart_array(dev_t startdev)
2658 {
2659         char b[BDEVNAME_SIZE];
2660         int err = -EINVAL, i;
2661         mdp_super_t *sb = NULL;
2662         mdk_rdev_t *start_rdev = NULL, *rdev;
2663
2664         start_rdev = md_import_device(startdev, 0, 0);
2665         if (IS_ERR(start_rdev))
2666                 return err;
2667
2668
2669         /* NOTE: this can only work for 0.90.0 superblocks */
2670         sb = (mdp_super_t*)page_address(start_rdev->sb_page);
2671         if (sb->major_version != 0 ||
2672             sb->minor_version != 90 ) {
2673                 printk(KERN_WARNING "md: can only autostart 0.90.0 arrays\n");
2674                 export_rdev(start_rdev);
2675                 return err;
2676         }
2677
2678         if (test_bit(Faulty, &start_rdev->flags)) {
2679                 printk(KERN_WARNING
2680                         "md: can not autostart based on faulty %s!\n",
2681                         bdevname(start_rdev->bdev,b));
2682                 export_rdev(start_rdev);
2683                 return err;
2684         }
2685         list_add(&start_rdev->same_set, &pending_raid_disks);
2686
2687         for (i = 0; i < MD_SB_DISKS; i++) {
2688                 mdp_disk_t *desc = sb->disks + i;
2689                 dev_t dev = MKDEV(desc->major, desc->minor);
2690
2691                 if (!dev)
2692                         continue;
2693                 if (dev == startdev)
2694                         continue;
2695                 if (MAJOR(dev) != desc->major || MINOR(dev) != desc->minor)
2696                         continue;
2697                 rdev = md_import_device(dev, 0, 0);
2698                 if (IS_ERR(rdev))
2699                         continue;
2700
2701                 list_add(&rdev->same_set, &pending_raid_disks);
2702         }
2703
2704         /*
2705          * possibly return codes
2706          */
2707         autorun_devices(0);
2708         return 0;
2709
2710 }
2711
2712
2713 static int get_version(void __user * arg)
2714 {
2715         mdu_version_t ver;
2716
2717         ver.major = MD_MAJOR_VERSION;
2718         ver.minor = MD_MINOR_VERSION;
2719         ver.patchlevel = MD_PATCHLEVEL_VERSION;
2720
2721         if (copy_to_user(arg, &ver, sizeof(ver)))
2722                 return -EFAULT;
2723
2724         return 0;
2725 }
2726
2727 static int get_array_info(mddev_t * mddev, void __user * arg)
2728 {
2729         mdu_array_info_t info;
2730         int nr,working,active,failed,spare;
2731         mdk_rdev_t *rdev;
2732         struct list_head *tmp;
2733
2734         nr=working=active=failed=spare=0;
2735         ITERATE_RDEV(mddev,rdev,tmp) {
2736                 nr++;
2737                 if (test_bit(Faulty, &rdev->flags))
2738                         failed++;
2739                 else {
2740                         working++;
2741                         if (test_bit(In_sync, &rdev->flags))
2742                                 active++;
2743                         else
2744                                 spare++;
2745                 }
2746         }
2747
2748         info.major_version = mddev->major_version;
2749         info.minor_version = mddev->minor_version;
2750         info.patch_version = MD_PATCHLEVEL_VERSION;
2751         info.ctime         = mddev->ctime;
2752         info.level         = mddev->level;
2753         info.size          = mddev->size;
2754         info.nr_disks      = nr;
2755         info.raid_disks    = mddev->raid_disks;
2756         info.md_minor      = mddev->md_minor;
2757         info.not_persistent= !mddev->persistent;
2758
2759         info.utime         = mddev->utime;
2760         info.state         = 0;
2761         if (mddev->in_sync)
2762                 info.state = (1<<MD_SB_CLEAN);
2763         if (mddev->bitmap && mddev->bitmap_offset)
2764                 info.state = (1<<MD_SB_BITMAP_PRESENT);
2765         info.active_disks  = active;
2766         info.working_disks = working;
2767         info.failed_disks  = failed;
2768         info.spare_disks   = spare;
2769
2770         info.layout        = mddev->layout;
2771         info.chunk_size    = mddev->chunk_size;
2772
2773         if (copy_to_user(arg, &info, sizeof(info)))
2774                 return -EFAULT;
2775
2776         return 0;
2777 }
2778
2779 static int get_bitmap_file(mddev_t * mddev, void __user * arg)
2780 {
2781         mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
2782         char *ptr, *buf = NULL;
2783         int err = -ENOMEM;
2784
2785         file = kmalloc(sizeof(*file), GFP_KERNEL);
2786         if (!file)
2787                 goto out;
2788
2789         /* bitmap disabled, zero the first byte and copy out */
2790         if (!mddev->bitmap || !mddev->bitmap->file) {
2791                 file->pathname[0] = '\0';
2792                 goto copy_out;
2793         }
2794
2795         buf = kmalloc(sizeof(file->pathname), GFP_KERNEL);
2796         if (!buf)
2797                 goto out;
2798
2799         ptr = file_path(mddev->bitmap->file, buf, sizeof(file->pathname));
2800         if (!ptr)
2801                 goto out;
2802
2803         strcpy(file->pathname, ptr);
2804
2805 copy_out:
2806         err = 0;
2807         if (copy_to_user(arg, file, sizeof(*file)))
2808                 err = -EFAULT;
2809 out:
2810         kfree(buf);
2811         kfree(file);
2812         return err;
2813 }
2814
2815 static int get_disk_info(mddev_t * mddev, void __user * arg)
2816 {
2817         mdu_disk_info_t info;
2818         unsigned int nr;
2819         mdk_rdev_t *rdev;
2820
2821         if (copy_from_user(&info, arg, sizeof(info)))
2822                 return -EFAULT;
2823
2824         nr = info.number;
2825
2826         rdev = find_rdev_nr(mddev, nr);
2827         if (rdev) {
2828                 info.major = MAJOR(rdev->bdev->bd_dev);
2829                 info.minor = MINOR(rdev->bdev->bd_dev);
2830                 info.raid_disk = rdev->raid_disk;
2831                 info.state = 0;
2832                 if (test_bit(Faulty, &rdev->flags))
2833                         info.state |= (1<<MD_DISK_FAULTY);
2834                 else if (test_bit(In_sync, &rdev->flags)) {
2835                         info.state |= (1<<MD_DISK_ACTIVE);
2836                         info.state |= (1<<MD_DISK_SYNC);
2837                 }
2838                 if (test_bit(WriteMostly, &rdev->flags))
2839                         info.state |= (1<<MD_DISK_WRITEMOSTLY);
2840         } else {
2841                 info.major = info.minor = 0;
2842                 info.raid_disk = -1;
2843                 info.state = (1<<MD_DISK_REMOVED);
2844         }
2845
2846         if (copy_to_user(arg, &info, sizeof(info)))
2847                 return -EFAULT;
2848
2849         return 0;
2850 }
2851
2852 static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
2853 {
2854         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
2855         mdk_rdev_t *rdev;
2856         dev_t dev = MKDEV(info->major,info->minor);
2857
2858         if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
2859                 return -EOVERFLOW;
2860
2861         if (!mddev->raid_disks) {
2862                 int err;
2863                 /* expecting a device which has a superblock */
2864                 rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
2865                 if (IS_ERR(rdev)) {
2866                         printk(KERN_WARNING
2867                                 "md: md_import_device returned %ld\n",
2868                                 PTR_ERR(rdev));
2869                         return PTR_ERR(rdev);
2870                 }
2871                 if (!list_empty(&mddev->disks)) {
2872                         mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
2873                                                         mdk_rdev_t, same_set);
2874                         int err = super_types[mddev->major_version]
2875                                 .load_super(rdev, rdev0, mddev->minor_version);
2876                         if (err < 0) {
2877                                 printk(KERN_WARNING
2878                                         "md: %s has different UUID to %s\n",
2879                                         bdevname(rdev->bdev,b),
2880                                         bdevname(rdev0->bdev,b2));
2881                                 export_rdev(rdev);
2882                                 return -EINVAL;
2883                         }
2884                 }
2885                 err = bind_rdev_to_array(rdev, mddev);
2886                 if (err)
2887                         export_rdev(rdev);
2888                 return err;
2889         }
2890
2891         /*
2892          * add_new_disk can be used once the array is assembled
2893          * to add "hot spares".  They must already have a superblock
2894          * written
2895          */
2896         if (mddev->pers) {
2897                 int err;
2898                 if (!mddev->pers->hot_add_disk) {
2899                         printk(KERN_WARNING
2900                                 "%s: personality does not support diskops!\n",
2901                                mdname(mddev));
2902                         return -EINVAL;
2903                 }
2904                 if (mddev->persistent)
2905                         rdev = md_import_device(dev, mddev->major_version,
2906                                                 mddev->minor_version);
2907                 else
2908                         rdev = md_import_device(dev, -1, -1);
2909                 if (IS_ERR(rdev)) {
2910                         printk(KERN_WARNING
2911                                 "md: md_import_device returned %ld\n",
2912                                 PTR_ERR(rdev));
2913                         return PTR_ERR(rdev);
2914                 }
2915                 /* set save_raid_disk if appropriate */
2916                 if (!mddev->persistent) {
2917                         if (info->state & (1<<MD_DISK_SYNC)  &&
2918                             info->raid_disk < mddev->raid_disks)
2919                                 rdev->raid_disk = info->raid_disk;
2920                         else
2921                                 rdev->raid_disk = -1;
2922                 } else
2923                         super_types[mddev->major_version].
2924                                 validate_super(mddev, rdev);
2925                 rdev->saved_raid_disk = rdev->raid_disk;
2926
2927                 clear_bit(In_sync, &rdev->flags); /* just to be sure */
2928                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
2929                         set_bit(WriteMostly, &rdev->flags);
2930
2931                 rdev->raid_disk = -1;
2932                 err = bind_rdev_to_array(rdev, mddev);
2933                 if (err)
2934                         export_rdev(rdev);
2935
2936                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2937                 md_wakeup_thread(mddev->thread);
2938                 return err;
2939         }
2940
2941         /* otherwise, add_new_disk is only allowed
2942          * for major_version==0 superblocks
2943          */
2944         if (mddev->major_version != 0) {
2945                 printk(KERN_WARNING "%s: ADD_NEW_DISK not supported\n",
2946                        mdname(mddev));
2947                 return -EINVAL;
2948         }
2949
2950         if (!(info->state & (1<<MD_DISK_FAULTY))) {
2951                 int err;
2952                 rdev = md_import_device (dev, -1, 0);
2953                 if (IS_ERR(rdev)) {
2954                         printk(KERN_WARNING
2955                                 "md: error, md_import_device() returned %ld\n",
2956                                 PTR_ERR(rdev));
2957                         return PTR_ERR(rdev);
2958                 }
2959                 rdev->desc_nr = info->number;
2960                 if (info->raid_disk < mddev->raid_disks)
2961                         rdev->raid_disk = info->raid_disk;
2962                 else
2963                         rdev->raid_disk = -1;
2964
2965                 rdev->flags = 0;
2966
2967                 if (rdev->raid_disk < mddev->raid_disks)
2968                         if (info->state & (1<<MD_DISK_SYNC))
2969                                 set_bit(In_sync, &rdev->flags);
2970
2971                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
2972                         set_bit(WriteMostly, &rdev->flags);
2973
2974                 if (!mddev->persistent) {
2975                         printk(KERN_INFO "md: nonpersistent superblock ...\n");
2976                         rdev->sb_offset = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
2977                 } else
2978                         rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
2979                 rdev->size = calc_dev_size(rdev, mddev->chunk_size);
2980
2981                 err = bind_rdev_to_array(rdev, mddev);
2982                 if (err) {
2983                         export_rdev(rdev);
2984                         return err;
2985                 }
2986         }
2987
2988         return 0;
2989 }
2990
2991 static int hot_remove_disk(mddev_t * mddev, dev_t dev)
2992 {
2993         char b[BDEVNAME_SIZE];
2994         mdk_rdev_t *rdev;
2995
2996         if (!mddev->pers)
2997                 return -ENODEV;
2998
2999         rdev = find_rdev(mddev, dev);
3000         if (!rdev)
3001                 return -ENXIO;
3002
3003         if (rdev->raid_disk >= 0)
3004                 goto busy;
3005
3006         kick_rdev_from_array(rdev);
3007         md_update_sb(mddev);
3008         md_new_event(mddev);
3009
3010         return 0;
3011 busy:
3012         printk(KERN_WARNING "md: cannot remove active disk %s from %s ... \n",
3013                 bdevname(rdev->bdev,b), mdname(mddev));
3014         return -EBUSY;
3015 }
3016
3017 static int hot_add_disk(mddev_t * mddev, dev_t dev)
3018 {
3019         char b[BDEVNAME_SIZE];
3020         int err;
3021         unsigned int size;
3022         mdk_rdev_t *rdev;
3023
3024         if (!mddev->pers)
3025                 return -ENODEV;
3026
3027         if (mddev->major_version != 0) {
3028                 printk(KERN_WARNING "%s: HOT_ADD may only be used with"
3029                         " version-0 superblocks.\n",
3030                         mdname(mddev));
3031                 return -EINVAL;
3032         }
3033         if (!mddev->pers->hot_add_disk) {
3034                 printk(KERN_WARNING
3035                         "%s: personality does not support diskops!\n",
3036                         mdname(mddev));
3037                 return -EINVAL;
3038         }
3039
3040         rdev = md_import_device (dev, -1, 0);
3041         if (IS_ERR(rdev)) {
3042                 printk(KERN_WARNING
3043                         "md: error, md_import_device() returned %ld\n",
3044                         PTR_ERR(rdev));
3045                 return -EINVAL;
3046         }
3047
3048         if (mddev->persistent)
3049                 rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
3050         else
3051                 rdev->sb_offset =
3052                         rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
3053
3054         size = calc_dev_size(rdev, mddev->chunk_size);
3055         rdev->size = size;
3056
3057         if (test_bit(Faulty, &rdev->flags)) {
3058                 printk(KERN_WARNING
3059                         "md: can not hot-add faulty %s disk to %s!\n",
3060                         bdevname(rdev->bdev,b), mdname(mddev));
3061                 err = -EINVAL;
3062                 goto abort_export;
3063         }
3064         clear_bit(In_sync, &rdev->flags);
3065         rdev->desc_nr = -1;
3066         err = bind_rdev_to_array(rdev, mddev);
3067         if (err)
3068                 goto abort_export;
3069
3070         /*
3071          * The rest should better be atomic, we can have disk failures
3072          * noticed in interrupt contexts ...
3073          */
3074
3075         if (rdev->desc_nr == mddev->max_disks) {
3076                 printk(KERN_WARNING "%s: can not hot-add to full array!\n",
3077                         mdname(mddev));
3078                 err = -EBUSY;
3079                 goto abort_unbind_export;
3080         }
3081
3082         rdev->raid_disk = -1;
3083
3084         md_update_sb(mddev);
3085
3086         /*
3087          * Kick recovery, maybe this spare has to be added to the
3088          * array immediately.
3089          */
3090         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3091         md_wakeup_thread(mddev->thread);
3092         md_new_event(mddev);
3093         return 0;
3094
3095 abort_unbind_export:
3096         unbind_rdev_from_array(rdev);
3097
3098 abort_export:
3099         export_rdev(rdev);
3100         return err;
3101 }
3102
3103 /* similar to deny_write_access, but accounts for our holding a reference
3104  * to the file ourselves */
3105 static int deny_bitmap_write_access(struct file * file)
3106 {
3107         struct inode *inode = file->f_mapping->host;
3108
3109         spin_lock(&inode->i_lock);
3110         if (atomic_read(&inode->i_writecount) > 1) {
3111                 spin_unlock(&inode->i_lock);
3112                 return -ETXTBSY;
3113         }
3114         atomic_set(&inode->i_writecount, -1);
3115         spin_unlock(&inode->i_lock);
3116
3117         return 0;
3118 }
3119
3120 static int set_bitmap_file(mddev_t *mddev, int fd)
3121 {
3122         int err;
3123
3124         if (mddev->pers) {
3125                 if (!mddev->pers->quiesce)
3126                         return -EBUSY;
3127                 if (mddev->recovery || mddev->sync_thread)
3128                         return -EBUSY;
3129                 /* we should be able to change the bitmap.. */
3130         }
3131
3132
3133         if (fd >= 0) {
3134                 if (mddev->bitmap)
3135                         return -EEXIST; /* cannot add when bitmap is present */
3136                 mddev->bitmap_file = fget(fd);
3137
3138                 if (mddev->bitmap_file == NULL) {
3139                         printk(KERN_ERR "%s: error: failed to get bitmap file\n",
3140                                mdname(mddev));
3141                         return -EBADF;
3142                 }
3143
3144                 err = deny_bitmap_write_access(mddev->bitmap_file);
3145                 if (err) {
3146                         printk(KERN_ERR "%s: error: bitmap file is already in use\n",
3147                                mdname(mddev));
3148                         fput(mddev->bitmap_file);
3149                         mddev->bitmap_file = NULL;
3150                         return err;
3151                 }
3152                 mddev->bitmap_offset = 0; /* file overrides offset */
3153         } else if (mddev->bitmap == NULL)
3154                 return -ENOENT; /* cannot remove what isn't there */
3155         err = 0;
3156         if (mddev->pers) {
3157                 mddev->pers->quiesce(mddev, 1);
3158                 if (fd >= 0)
3159                         err = bitmap_create(mddev);
3160                 if (fd < 0 || err)
3161                         bitmap_destroy(mddev);
3162                 mddev->pers->quiesce(mddev, 0);
3163         } else if (fd < 0) {
3164                 if (mddev->bitmap_file)
3165                         fput(mddev->bitmap_file);
3166                 mddev->bitmap_file = NULL;
3167         }
3168
3169         return err;
3170 }
3171
3172 /*
3173  * set_array_info is used two different ways
3174  * The original usage is when creating a new array.
3175  * In this usage, raid_disks is > 0 and it together with
3176  *  level, size, not_persistent,layout,chunksize determine the
3177  *  shape of the array.
3178  *  This will always create an array with a type-0.90.0 superblock.
3179  * The newer usage is when assembling an array.
3180  *  In this case raid_disks will be 0, and the major_version field is
3181  *  use to determine which style super-blocks are to be found on the devices.
3182  *  The minor and patch _version numbers are also kept incase the
3183  *  super_block handler wishes to interpret them.
3184  */
3185 static int set_array_info(mddev_t * mddev, mdu_array_info_t *info)
3186 {
3187
3188         if (info->raid_disks == 0) {
3189                 /* just setting version number for superblock loading */
3190                 if (info->major_version < 0 ||
3191                     info->major_version >= sizeof(super_types)/sizeof(super_types[0]) ||
3192                     super_types[info->major_version].name == NULL) {
3193                         /* maybe try to auto-load a module? */
3194                         printk(KERN_INFO
3195                                 "md: superblock version %d not known\n",
3196                                 info->major_version);
3197                         return -EINVAL;
3198                 }
3199                 mddev->major_version = info->major_version;
3200                 mddev->minor_version = info->minor_version;
3201                 mddev->patch_version = info->patch_version;
3202                 return 0;
3203         }
3204         mddev->major_version = MD_MAJOR_VERSION;
3205         mddev->minor_version = MD_MINOR_VERSION;
3206         mddev->patch_version = MD_PATCHLEVEL_VERSION;
3207         mddev->ctime         = get_seconds();
3208
3209         mddev->level         = info->level;
3210         mddev->size          = info->size;
3211         mddev->raid_disks    = info->raid_disks;
3212         /* don't set md_minor, it is determined by which /dev/md* was
3213          * openned
3214          */
3215         if (info->state & (1<<MD_SB_CLEAN))
3216                 mddev->recovery_cp = MaxSector;
3217         else
3218                 mddev->recovery_cp = 0;
3219         mddev->persistent    = ! info->not_persistent;
3220
3221         mddev->layout        = info->layout;
3222         mddev->chunk_size    = info->chunk_size;
3223
3224         mddev->max_disks     = MD_SB_DISKS;
3225
3226         mddev->sb_dirty      = 1;
3227
3228         mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
3229         mddev->bitmap_offset = 0;
3230
3231         /*
3232          * Generate a 128 bit UUID
3233          */
3234         get_random_bytes(mddev->uuid, 16);
3235
3236         return 0;
3237 }
3238
3239 static int update_size(mddev_t *mddev, unsigned long size)
3240 {
3241         mdk_rdev_t * rdev;
3242         int rv;
3243         struct list_head *tmp;
3244
3245         if (mddev->pers->resize == NULL)
3246                 return -EINVAL;
3247         /* The "size" is the amount of each device that is used.
3248          * This can only make sense for arrays with redundancy.
3249          * linear and raid0 always use whatever space is available
3250          * We can only consider changing the size if no resync
3251          * or reconstruction is happening, and if the new size
3252          * is acceptable. It must fit before the sb_offset or,
3253          * if that is <data_offset, it must fit before the
3254          * size of each device.
3255          * If size is zero, we find the largest size that fits.
3256          */
3257         if (mddev->sync_thread)
3258                 return -EBUSY;
3259         ITERATE_RDEV(mddev,rdev,tmp) {
3260                 sector_t avail;
3261                 int fit = (size == 0);
3262                 if (rdev->sb_offset > rdev->data_offset)
3263                         avail = (rdev->sb_offset*2) - rdev->data_offset;
3264                 else
3265                         avail = get_capacity(rdev->bdev->bd_disk)
3266                                 - rdev->data_offset;
3267                 if (fit && (size == 0 || size > avail/2))
3268                         size = avail/2;
3269                 if (avail < ((sector_t)size << 1))
3270                         return -ENOSPC;
3271         }
3272         rv = mddev->pers->resize(mddev, (sector_t)size *2);
3273         if (!rv) {
3274                 struct block_device *bdev;
3275
3276                 bdev = bdget_disk(mddev->gendisk, 0);
3277                 if (bdev) {
3278                         down(&bdev->bd_inode->i_sem);
3279                         i_size_write(bdev->bd_inode, mddev->array_size << 10);
3280                         up(&bdev->bd_inode->i_sem);
3281                         bdput(bdev);
3282                 }
3283         }
3284         return rv;
3285 }
3286
3287 static int update_raid_disks(mddev_t *mddev, int raid_disks)
3288 {
3289         int rv;
3290         /* change the number of raid disks */
3291         if (mddev->pers->reshape == NULL)
3292                 return -EINVAL;
3293         if (raid_disks <= 0 ||
3294             raid_disks >= mddev->max_disks)
3295                 return -EINVAL;
3296         if (mddev->sync_thread)
3297                 return -EBUSY;
3298         rv = mddev->pers->reshape(mddev, raid_disks);
3299         if (!rv) {
3300                 struct block_device *bdev;
3301
3302                 bdev = bdget_disk(mddev->gendisk, 0);
3303                 if (bdev) {
3304                         down(&bdev->bd_inode->i_sem);
3305                         i_size_write(bdev->bd_inode, mddev->array_size << 10);
3306                         up(&bdev->bd_inode->i_sem);
3307                         bdput(bdev);
3308                 }
3309         }
3310         return rv;
3311 }
3312
3313
3314 /*
3315  * update_array_info is used to change the configuration of an
3316  * on-line array.
3317  * The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
3318  * fields in the info are checked against the array.
3319  * Any differences that cannot be handled will cause an error.
3320  * Normally, only one change can be managed at a time.
3321  */
3322 static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
3323 {
3324         int rv = 0;
3325         int cnt = 0;
3326         int state = 0;
3327
3328         /* calculate expected state,ignoring low bits */
3329         if (mddev->bitmap && mddev->bitmap_offset)
3330                 state |= (1 << MD_SB_BITMAP_PRESENT);
3331
3332         if (mddev->major_version != info->major_version ||
3333             mddev->minor_version != info->minor_version ||
3334 /*          mddev->patch_version != info->patch_version || */
3335             mddev->ctime         != info->ctime         ||
3336             mddev->level         != info->level         ||
3337 /*          mddev->layout        != info->layout        || */
3338             !mddev->persistent   != info->not_persistent||
3339             mddev->chunk_size    != info->chunk_size    ||
3340             /* ignore bottom 8 bits of state, and allow SB_BITMAP_PRESENT to change */
3341             ((state^info->state) & 0xfffffe00)
3342                 )
3343                 return -EINVAL;
3344         /* Check there is only one change */
3345         if (mddev->size != info->size) cnt++;
3346         if (mddev->raid_disks != info->raid_disks) cnt++;
3347         if (mddev->layout != info->layout) cnt++;
3348         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) cnt++;
3349         if (cnt == 0) return 0;
3350         if (cnt > 1) return -EINVAL;
3351
3352         if (mddev->layout != info->layout) {
3353                 /* Change layout
3354                  * we don't need to do anything at the md level, the
3355                  * personality will take care of it all.
3356                  */
3357                 if (mddev->pers->reconfig == NULL)
3358                         return -EINVAL;
3359                 else
3360                         return mddev->pers->reconfig(mddev, info->layout, -1);
3361         }
3362         if (mddev->size != info->size)
3363                 rv = update_size(mddev, info->size);
3364
3365         if (mddev->raid_disks    != info->raid_disks)
3366                 rv = update_raid_disks(mddev, info->raid_disks);
3367
3368         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) {
3369                 if (mddev->pers->quiesce == NULL)
3370                         return -EINVAL;
3371                 if (mddev->recovery || mddev->sync_thread)
3372                         return -EBUSY;
3373                 if (info->state & (1<<MD_SB_BITMAP_PRESENT)) {
3374                         /* add the bitmap */
3375                         if (mddev->bitmap)
3376                                 return -EEXIST;
3377                         if (mddev->default_bitmap_offset == 0)
3378                                 return -EINVAL;
3379                         mddev->bitmap_offset = mddev->default_bitmap_offset;
3380                         mddev->pers->quiesce(mddev, 1);
3381                         rv = bitmap_create(mddev);
3382                         if (rv)
3383                                 bitmap_destroy(mddev);
3384                         mddev->pers->quiesce(mddev, 0);
3385                 } else {
3386                         /* remove the bitmap */
3387                         if (!mddev->bitmap)
3388                                 return -ENOENT;
3389                         if (mddev->bitmap->file)
3390                                 return -EINVAL;
3391                         mddev->pers->quiesce(mddev, 1);
3392                         bitmap_destroy(mddev);
3393                         mddev->pers->quiesce(mddev, 0);
3394                         mddev->bitmap_offset = 0;
3395                 }
3396         }
3397         md_update_sb(mddev);
3398         return rv;
3399 }
3400
3401 static int set_disk_faulty(mddev_t *mddev, dev_t dev)
3402 {
3403         mdk_rdev_t *rdev;
3404
3405         if (mddev->pers == NULL)
3406                 return -ENODEV;
3407
3408         rdev = find_rdev(mddev, dev);
3409         if (!rdev)
3410                 return -ENODEV;
3411
3412         md_error(mddev, rdev);
3413         return 0;
3414 }
3415
3416 static int md_ioctl(struct inode *inode, struct file *file,
3417                         unsigned int cmd, unsigned long arg)
3418 {
3419         int err = 0;
3420         void __user *argp = (void __user *)arg;
3421         struct hd_geometry __user *loc = argp;
3422         mddev_t *mddev = NULL;
3423
3424         if (!capable(CAP_SYS_ADMIN))
3425                 return -EACCES;
3426
3427         /*
3428          * Commands dealing with the RAID driver but not any
3429          * particular array:
3430          */
3431         switch (cmd)
3432         {
3433                 case RAID_VERSION:
3434                         err = get_version(argp);
3435                         goto done;
3436
3437                 case PRINT_RAID_DEBUG:
3438                         err = 0;
3439                         md_print_devices();
3440                         goto done;
3441
3442 #ifndef MODULE
3443                 case RAID_AUTORUN:
3444                         err = 0;
3445                         autostart_arrays(arg);
3446                         goto done;
3447 #endif
3448                 default:;
3449         }
3450
3451         /*
3452          * Commands creating/starting a new array:
3453          */
3454
3455         mddev = inode->i_bdev->bd_disk->private_data;
3456
3457         if (!mddev) {
3458                 BUG();
3459                 goto abort;
3460         }
3461
3462
3463         if (cmd == START_ARRAY) {
3464                 /* START_ARRAY doesn't need to lock the array as autostart_array
3465                  * does the locking, and it could even be a different array
3466                  */
3467                 static int cnt = 3;
3468                 if (cnt > 0 ) {
3469                         printk(KERN_WARNING
3470                                "md: %s(pid %d) used deprecated START_ARRAY ioctl. "
3471                                "This will not be supported beyond July 2006\n",
3472                                current->comm, current->pid);
3473                         cnt--;
3474                 }
3475                 err = autostart_array(new_decode_dev(arg));
3476                 if (err) {
3477                         printk(KERN_WARNING "md: autostart failed!\n");
3478                         goto abort;
3479                 }
3480                 goto done;
3481         }
3482
3483         err = mddev_lock(mddev);
3484         if (err) {
3485                 printk(KERN_INFO
3486                         "md: ioctl lock interrupted, reason %d, cmd %d\n",
3487                         err, cmd);
3488                 goto abort;
3489         }
3490
3491         switch (cmd)
3492         {
3493                 case SET_ARRAY_INFO:
3494                         {
3495                                 mdu_array_info_t info;
3496                                 if (!arg)
3497                                         memset(&info, 0, sizeof(info));
3498                                 else if (copy_from_user(&info, argp, sizeof(info))) {
3499                                         err = -EFAULT;
3500                                         goto abort_unlock;
3501                                 }
3502                                 if (mddev->pers) {
3503                                         err = update_array_info(mddev, &info);
3504                                         if (err) {
3505                                                 printk(KERN_WARNING "md: couldn't update"
3506                                                        " array info. %d\n", err);
3507                                                 goto abort_unlock;
3508                                         }
3509                                         goto done_unlock;
3510                                 }
3511                                 if (!list_empty(&mddev->disks)) {
3512                                         printk(KERN_WARNING
3513                                                "md: array %s already has disks!\n",
3514                                                mdname(mddev));
3515                                         err = -EBUSY;
3516                                         goto abort_unlock;
3517                                 }
3518                                 if (mddev->raid_disks) {
3519                                         printk(KERN_WARNING
3520                                                "md: array %s already initialised!\n",
3521                                                mdname(mddev));
3522                                         err = -EBUSY;
3523                                         goto abort_unlock;
3524                                 }
3525                                 err = set_array_info(mddev, &info);
3526                                 if (err) {
3527                                         printk(KERN_WARNING "md: couldn't set"
3528                                                " array info. %d\n", err);
3529                                         goto abort_unlock;
3530                                 }
3531                         }
3532                         goto done_unlock;
3533
3534                 default:;
3535         }
3536
3537         /*
3538          * Commands querying/configuring an existing array:
3539          */
3540         /* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
3541          * RUN_ARRAY, and SET_BITMAP_FILE are allowed */
3542         if (!mddev->raid_disks && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
3543                         && cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE) {
3544                 err = -ENODEV;
3545                 goto abort_unlock;
3546         }
3547
3548         /*
3549          * Commands even a read-only array can execute:
3550          */
3551         switch (cmd)
3552         {
3553                 case GET_ARRAY_INFO:
3554                         err = get_array_info(mddev, argp);
3555                         goto done_unlock;
3556
3557                 case GET_BITMAP_FILE:
3558                         err = get_bitmap_file(mddev, argp);
3559                         goto done_unlock;
3560
3561                 case GET_DISK_INFO:
3562                         err = get_disk_info(mddev, argp);
3563                         goto done_unlock;
3564
3565                 case RESTART_ARRAY_RW:
3566                         err = restart_array(mddev);
3567                         goto done_unlock;
3568
3569                 case STOP_ARRAY:
3570                         err = do_md_stop (mddev, 0);
3571                         goto done_unlock;
3572
3573                 case STOP_ARRAY_RO:
3574                         err = do_md_stop (mddev, 1);
3575                         goto done_unlock;
3576
3577         /*
3578          * We have a problem here : there is no easy way to give a CHS
3579          * virtual geometry. We currently pretend that we have a 2 heads
3580          * 4 sectors (with a BIG number of cylinders...). This drives
3581          * dosfs just mad... ;-)
3582          */
3583                 case HDIO_GETGEO:
3584                         if (!loc) {
3585                                 err = -EINVAL;
3586                                 goto abort_unlock;
3587                         }
3588                         err = put_user (2, (char __user *) &loc->heads);
3589                         if (err)
3590                                 goto abort_unlock;
3591                         err = put_user (4, (char __user *) &loc->sectors);
3592                         if (err)
3593                                 goto abort_unlock;
3594                         err = put_user(get_capacity(mddev->gendisk)/8,
3595                                         (short __user *) &loc->cylinders);
3596                         if (err)
3597                                 goto abort_unlock;
3598                         err = put_user (get_start_sect(inode->i_bdev),
3599                                                 (long __user *) &loc->start);
3600                         goto done_unlock;
3601         }
3602
3603         /*
3604          * The remaining ioctls are changing the state of the
3605          * superblock, so we do not allow them on read-only arrays.
3606          * However non-MD ioctls (e.g. get-size) will still come through
3607          * here and hit the 'default' below, so only disallow
3608          * 'md' ioctls, and switch to rw mode if started auto-readonly.
3609          */
3610         if (_IOC_TYPE(cmd) == MD_MAJOR &&
3611             mddev->ro && mddev->pers) {
3612                 if (mddev->ro == 2) {
3613                         mddev->ro = 0;
3614                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3615                 md_wakeup_thread(mddev->thread);
3616
3617                 } else {
3618                         err = -EROFS;
3619                         goto abort_unlock;
3620                 }
3621         }
3622
3623         switch (cmd)
3624         {
3625                 case ADD_NEW_DISK:
3626                 {
3627                         mdu_disk_info_t info;
3628                         if (copy_from_user(&info, argp, sizeof(info)))
3629                                 err = -EFAULT;
3630                         else
3631                                 err = add_new_disk(mddev, &info);
3632                         goto done_unlock;
3633                 }
3634
3635                 case HOT_REMOVE_DISK:
3636                         err = hot_remove_disk(mddev, new_decode_dev(arg));
3637                         goto done_unlock;
3638
3639                 case HOT_ADD_DISK:
3640                         err = hot_add_disk(mddev, new_decode_dev(arg));
3641                         goto done_unlock;
3642
3643                 case SET_DISK_FAULTY:
3644                         err = set_disk_faulty(mddev, new_decode_dev(arg));
3645                         goto done_unlock;
3646
3647                 case RUN_ARRAY:
3648                         err = do_md_run (mddev);
3649                         goto done_unlock;
3650
3651                 case SET_BITMAP_FILE:
3652                         err = set_bitmap_file(mddev, (int)arg);
3653                         goto done_unlock;
3654
3655                 default:
3656                         if (_IOC_TYPE(cmd) == MD_MAJOR)
3657                                 printk(KERN_WARNING "md: %s(pid %d) used"
3658                                         " obsolete MD ioctl, upgrade your"
3659                                         " software to use new ictls.\n",
3660                                         current->comm, current->pid);
3661                         err = -EINVAL;
3662                         goto abort_unlock;
3663         }
3664
3665 done_unlock:
3666 abort_unlock:
3667         mddev_unlock(mddev);
3668
3669         return err;
3670 done:
3671         if (err)
3672                 MD_BUG();
3673 abort:
3674         return err;
3675 }
3676
3677 static int md_open(struct inode *inode, struct file *file)
3678 {
3679         /*
3680          * Succeed if we can lock the mddev, which confirms that
3681          * it isn't being stopped right now.
3682          */
3683         mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
3684         int err;
3685
3686         if ((err = mddev_lock(mddev)))
3687                 goto out;
3688
3689         err = 0;
3690         mddev_get(mddev);
3691         mddev_unlock(mddev);
3692
3693         check_disk_change(inode->i_bdev);
3694  out:
3695         return err;
3696 }
3697
3698 static int md_release(struct inode *inode, struct file * file)
3699 {
3700         mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
3701
3702         if (!mddev)
3703                 BUG();
3704         mddev_put(mddev);
3705
3706         return 0;
3707 }
3708
3709 static int md_media_changed(struct gendisk *disk)
3710 {
3711         mddev_t *mddev = disk->private_data;
3712
3713         return mddev->changed;
3714 }
3715
3716 static int md_revalidate(struct gendisk *disk)
3717 {
3718         mddev_t *mddev = disk->private_data;
3719
3720         mddev->changed = 0;
3721         return 0;
3722 }
3723 static struct block_device_operations md_fops =
3724 {
3725         .owner          = THIS_MODULE,
3726         .open           = md_open,
3727         .release        = md_release,
3728         .ioctl          = md_ioctl,
3729         .media_changed  = md_media_changed,
3730         .revalidate_disk= md_revalidate,
3731 };
3732
3733 static int md_thread(void * arg)
3734 {
3735         mdk_thread_t *thread = arg;
3736
3737         /*
3738          * md_thread is a 'system-thread', it's priority should be very
3739          * high. We avoid resource deadlocks individually in each
3740          * raid personality. (RAID5 does preallocation) We also use RR and
3741          * the very same RT priority as kswapd, thus we will never get
3742          * into a priority inversion deadlock.
3743          *
3744          * we definitely have to have equal or higher priority than
3745          * bdflush, otherwise bdflush will deadlock if there are too
3746          * many dirty RAID5 blocks.
3747          */
3748
3749         allow_signal(SIGKILL);
3750         while (!kthread_should_stop()) {
3751
3752                 /* We need to wait INTERRUPTIBLE so that
3753                  * we don't add to the load-average.
3754                  * That means we need to be sure no signals are
3755                  * pending
3756                  */
3757                 if (signal_pending(current))
3758                         flush_signals(current);
3759
3760                 wait_event_interruptible_timeout
3761                         (thread->wqueue,
3762                          test_bit(THREAD_WAKEUP, &thread->flags)
3763                          || kthread_should_stop(),
3764                          thread->timeout);
3765                 try_to_freeze();
3766
3767                 clear_bit(THREAD_WAKEUP, &thread->flags);
3768
3769                 thread->run(thread->mddev);
3770         }
3771
3772         return 0;
3773 }
3774
3775 void md_wakeup_thread(mdk_thread_t *thread)
3776 {
3777         if (thread) {
3778                 dprintk("md: waking up MD thread %s.\n", thread->tsk->comm);
3779                 set_bit(THREAD_WAKEUP, &thread->flags);
3780                 wake_up(&thread->wqueue);
3781         }
3782 }
3783
3784 mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev,
3785                                  const char *name)
3786 {
3787         mdk_thread_t *thread;
3788
3789         thread = kzalloc(sizeof(mdk_thread_t), GFP_KERNEL);
3790         if (!thread)
3791                 return NULL;
3792
3793         init_waitqueue_head(&thread->wqueue);
3794
3795         thread->run = run;
3796         thread->mddev = mddev;
3797         thread->timeout = MAX_SCHEDULE_TIMEOUT;
3798         thread->tsk = kthread_run(md_thread, thread, name, mdname(thread->mddev));
3799         if (IS_ERR(thread->tsk)) {
3800                 kfree(thread);
3801                 return NULL;
3802         }
3803         return thread;
3804 }
3805
3806 void md_unregister_thread(mdk_thread_t *thread)
3807 {
3808         dprintk("interrupting MD-thread pid %d\n", thread->tsk->pid);
3809
3810         kthread_stop(thread->tsk);
3811         kfree(thread);
3812 }
3813
3814 void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
3815 {
3816         if (!mddev) {
3817                 MD_BUG();
3818                 return;
3819         }
3820
3821         if (!rdev || test_bit(Faulty, &rdev->flags))
3822                 return;
3823 /*
3824         dprintk("md_error dev:%s, rdev:(%d:%d), (caller: %p,%p,%p,%p).\n",
3825                 mdname(mddev),
3826                 MAJOR(rdev->bdev->bd_dev), MINOR(rdev->bdev->bd_dev),
3827                 __builtin_return_address(0),__builtin_return_address(1),
3828                 __builtin_return_address(2),__builtin_return_address(3));
3829 */
3830         if (!mddev->pers->error_handler)
3831                 return;
3832         mddev->pers->error_handler(mddev,rdev);
3833         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3834         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3835         md_wakeup_thread(mddev->thread);
3836         md_new_event(mddev);
3837 }
3838
3839 /* seq_file implementation /proc/mdstat */
3840
3841 static void status_unused(struct seq_file *seq)
3842 {
3843         int i = 0;
3844         mdk_rdev_t *rdev;
3845         struct list_head *tmp;
3846
3847         seq_printf(seq, "unused devices: ");
3848
3849         ITERATE_RDEV_PENDING(rdev,tmp) {
3850                 char b[BDEVNAME_SIZE];
3851                 i++;
3852                 seq_printf(seq, "%s ",
3853                               bdevname(rdev->bdev,b));
3854         }
3855         if (!i)
3856                 seq_printf(seq, "<none>");
3857
3858         seq_printf(seq, "\n");
3859 }
3860
3861
3862 static void status_resync(struct seq_file *seq, mddev_t * mddev)
3863 {
3864         unsigned long max_blocks, resync, res, dt, db, rt;
3865
3866         resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active))/2;
3867
3868         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
3869                 max_blocks = mddev->resync_max_sectors >> 1;
3870         else
3871                 max_blocks = mddev->size;
3872
3873         /*
3874          * Should not happen.
3875          */
3876         if (!max_blocks) {
3877                 MD_BUG();
3878                 return;
3879         }
3880         res = (resync/1024)*1000/(max_blocks/1024 + 1);
3881         {
3882                 int i, x = res/50, y = 20-x;
3883                 seq_printf(seq, "[");
3884                 for (i = 0; i < x; i++)
3885                         seq_printf(seq, "=");
3886                 seq_printf(seq, ">");
3887                 for (i = 0; i < y; i++)
3888                         seq_printf(seq, ".");
3889                 seq_printf(seq, "] ");
3890         }
3891         seq_printf(seq, " %s =%3lu.%lu%% (%lu/%lu)",
3892                       (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
3893                        "resync" : "recovery"),
3894                       res/10, res % 10, resync, max_blocks);
3895
3896         /*
3897          * We do not want to overflow, so the order of operands and
3898          * the * 100 / 100 trick are important. We do a +1 to be
3899          * safe against division by zero. We only estimate anyway.
3900          *
3901          * dt: time from mark until now
3902          * db: blocks written from mark until now
3903          * rt: remaining time
3904          */
3905         dt = ((jiffies - mddev->resync_mark) / HZ);
3906         if (!dt) dt++;
3907         db = resync - (mddev->resync_mark_cnt/2);
3908         rt = (dt * ((max_blocks-resync) / (db/100+1)))/100;
3909
3910         seq_printf(seq, " finish=%lu.%lumin", rt / 60, (rt % 60)/6);
3911
3912         seq_printf(seq, " speed=%ldK/sec", db/dt);
3913 }
3914
3915 static void *md_seq_start(struct seq_file *seq, loff_t *pos)
3916 {
3917         struct list_head *tmp;
3918         loff_t l = *pos;
3919         mddev_t *mddev;
3920
3921         if (l >= 0x10000)
3922                 return NULL;
3923         if (!l--)
3924                 /* header */
3925                 return (void*)1;
3926
3927         spin_lock(&all_mddevs_lock);
3928         list_for_each(tmp,&all_mddevs)
3929                 if (!l--) {
3930                         mddev = list_entry(tmp, mddev_t, all_mddevs);
3931                         mddev_get(mddev);
3932                         spin_unlock(&all_mddevs_lock);
3933                         return mddev;
3934                 }
3935         spin_unlock(&all_mddevs_lock);
3936         if (!l--)
3937                 return (void*)2;/* tail */
3938         return NULL;
3939 }
3940
3941 static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3942 {
3943         struct list_head *tmp;
3944         mddev_t *next_mddev, *mddev = v;
3945
3946         ++*pos;
3947         if (v == (void*)2)
3948                 return NULL;
3949
3950         spin_lock(&all_mddevs_lock);
3951         if (v == (void*)1)
3952                 tmp = all_mddevs.next;
3953         else
3954                 tmp = mddev->all_mddevs.next;
3955         if (tmp != &all_mddevs)
3956                 next_mddev = mddev_get(list_entry(tmp,mddev_t,all_mddevs));
3957         else {
3958                 next_mddev = (void*)2;
3959                 *pos = 0x10000;
3960         }
3961         spin_unlock(&all_mddevs_lock);
3962
3963         if (v != (void*)1)
3964                 mddev_put(mddev);
3965         return next_mddev;
3966
3967 }
3968
3969 static void md_seq_stop(struct seq_file *seq, void *v)
3970 {
3971         mddev_t *mddev = v;
3972
3973         if (mddev && v != (void*)1 && v != (void*)2)
3974                 mddev_put(mddev);
3975 }
3976
3977 struct mdstat_info {
3978         int event;
3979 };
3980
3981 static int md_seq_show(struct seq_file *seq, void *v)
3982 {
3983         mddev_t *mddev = v;
3984         sector_t size;
3985         struct list_head *tmp2;
3986         mdk_rdev_t *rdev;
3987         struct mdstat_info *mi = seq->private;
3988         struct bitmap *bitmap;
3989
3990         if (v == (void*)1) {
3991                 struct mdk_personality *pers;
3992                 seq_printf(seq, "Personalities : ");
3993                 spin_lock(&pers_lock);
3994                 list_for_each_entry(pers, &pers_list, list)
3995                         seq_printf(seq, "[%s] ", pers->name);
3996
3997                 spin_unlock(&pers_lock);
3998                 seq_printf(seq, "\n");
3999                 mi->event = atomic_read(&md_event_count);
4000                 return 0;
4001         }
4002         if (v == (void*)2) {
4003                 status_unused(seq);
4004                 return 0;
4005         }
4006
4007         if (mddev_lock(mddev)!=0)
4008                 return -EINTR;
4009         if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
4010                 seq_printf(seq, "%s : %sactive", mdname(mddev),
4011                                                 mddev->pers ? "" : "in");
4012                 if (mddev->pers) {
4013                         if (mddev->ro==1)
4014                                 seq_printf(seq, " (read-only)");
4015                         if (mddev->ro==2)
4016                                 seq_printf(seq, "(auto-read-only)");
4017                         seq_printf(seq, " %s", mddev->pers->name);
4018                 }
4019
4020                 size = 0;
4021                 ITERATE_RDEV(mddev,rdev,tmp2) {
4022                         char b[BDEVNAME_SIZE];
4023                         seq_printf(seq, " %s[%d]",
4024                                 bdevname(rdev->bdev,b), rdev->desc_nr);
4025                         if (test_bit(WriteMostly, &rdev->flags))
4026                                 seq_printf(seq, "(W)");
4027                         if (test_bit(Faulty, &rdev->flags)) {
4028                                 seq_printf(seq, "(F)");
4029                                 continue;
4030                         } else if (rdev->raid_disk < 0)
4031                                 seq_printf(seq, "(S)"); /* spare */
4032                         size += rdev->size;
4033                 }
4034
4035                 if (!list_empty(&mddev->disks)) {
4036                         if (mddev->pers)
4037                                 seq_printf(seq, "\n      %llu blocks",
4038                                         (unsigned long long)mddev->array_size);
4039                         else
4040                                 seq_printf(seq, "\n      %llu blocks",
4041                                         (unsigned long long)size);
4042                 }
4043                 if (mddev->persistent) {
4044                         if (mddev->major_version != 0 ||
4045                             mddev->minor_version != 90) {
4046                                 seq_printf(seq," super %d.%d",
4047                                            mddev->major_version,
4048                                            mddev->minor_version);
4049                         }
4050                 } else
4051                         seq_printf(seq, " super non-persistent");
4052
4053                 if (mddev->pers) {
4054                         mddev->pers->status (seq, mddev);
4055                         seq_printf(seq, "\n      ");
4056                         if (mddev->pers->sync_request) {
4057                                 if (mddev->curr_resync > 2) {
4058                                         status_resync (seq, mddev);
4059                                         seq_printf(seq, "\n      ");
4060                                 } else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
4061                                         seq_printf(seq, "\tresync=DELAYED\n      ");
4062                                 else if (mddev->recovery_cp < MaxSector)
4063                                         seq_printf(seq, "\tresync=PENDING\n      ");
4064                         }
4065                 } else
4066                         seq_printf(seq, "\n       ");
4067
4068                 if ((bitmap = mddev->bitmap)) {
4069                         unsigned long chunk_kb;
4070                         unsigned long flags;
4071                         spin_lock_irqsave(&bitmap->lock, flags);
4072                         chunk_kb = bitmap->chunksize >> 10;
4073                         seq_printf(seq, "bitmap: %lu/%lu pages [%luKB], "
4074                                 "%lu%s chunk",
4075                                 bitmap->pages - bitmap->missing_pages,
4076                                 bitmap->pages,
4077                                 (bitmap->pages - bitmap->missing_pages)
4078                                         << (PAGE_SHIFT - 10),
4079                                 chunk_kb ? chunk_kb : bitmap->chunksize,
4080                                 chunk_kb ? "KB" : "B");
4081                         if (bitmap->file) {
4082                                 seq_printf(seq, ", file: ");
4083                                 seq_path(seq, bitmap->file->f_vfsmnt,
4084                                          bitmap->file->f_dentry," \t\n");
4085                         }
4086
4087                         seq_printf(seq, "\n");
4088                         spin_unlock_irqrestore(&bitmap->lock, flags);
4089                 }
4090
4091                 seq_printf(seq, "\n");
4092         }
4093         mddev_unlock(mddev);
4094
4095         return 0;
4096 }
4097
4098 static struct seq_operations md_seq_ops = {
4099         .start  = md_seq_start,
4100         .next   = md_seq_next,
4101         .stop   = md_seq_stop,
4102         .show   = md_seq_show,
4103 };
4104
4105 static int md_seq_open(struct inode *inode, struct file *file)
4106 {
4107         int error;
4108         struct mdstat_info *mi = kmalloc(sizeof(*mi), GFP_KERNEL);
4109         if (mi == NULL)
4110                 return -ENOMEM;
4111
4112         error = seq_open(file, &md_seq_ops);
4113         if (error)
4114                 kfree(mi);
4115         else {
4116                 struct seq_file *p = file->private_data;
4117                 p->private = mi;
4118                 mi->event = atomic_read(&md_event_count);
4119         }
4120         return error;
4121 }
4122
4123 static int md_seq_release(struct inode *inode, struct file *file)
4124 {
4125         struct seq_file *m = file->private_data;
4126         struct mdstat_info *mi = m->private;
4127         m->private = NULL;
4128         kfree(mi);
4129         return seq_release(inode, file);
4130 }
4131
4132 static unsigned int mdstat_poll(struct file *filp, poll_table *wait)
4133 {
4134         struct seq_file *m = filp->private_data;
4135         struct mdstat_info *mi = m->private;
4136         int mask;
4137
4138         poll_wait(filp, &md_event_waiters, wait);
4139
4140         /* always allow read */
4141         mask = POLLIN | POLLRDNORM;
4142
4143         if (mi->event != atomic_read(&md_event_count))
4144                 mask |= POLLERR | POLLPRI;
4145         return mask;
4146 }
4147
4148 static struct file_operations md_seq_fops = {
4149         .open           = md_seq_open,
4150         .read           = seq_read,
4151         .llseek         = seq_lseek,
4152         .release        = md_seq_release,
4153         .poll           = mdstat_poll,
4154 };
4155
4156 int register_md_personality(struct mdk_personality *p)
4157 {
4158         spin_lock(&pers_lock);
4159         list_add_tail(&p->list, &pers_list);
4160         printk(KERN_INFO "md: %s personality registered for level %d\n", p->name, p->level);
4161         spin_unlock(&pers_lock);
4162         return 0;
4163 }
4164
4165 int unregister_md_personality(struct mdk_personality *p)
4166 {
4167         printk(KERN_INFO "md: %s personality unregistered\n", p->name);
4168         spin_lock(&pers_lock);
4169         list_del_init(&p->list);
4170         spin_unlock(&pers_lock);
4171         return 0;
4172 }
4173
4174 static int is_mddev_idle(mddev_t *mddev)
4175 {
4176         mdk_rdev_t * rdev;
4177         struct list_head *tmp;
4178         int idle;
4179         unsigned long curr_events;
4180
4181         idle = 1;
4182         ITERATE_RDEV(mddev,rdev,tmp) {
4183                 struct gendisk *disk = rdev->bdev->bd_contains->bd_disk;
4184                 curr_events = disk_stat_read(disk, sectors[0]) +
4185                                 disk_stat_read(disk, sectors[1]) -
4186                                 atomic_read(&disk->sync_io);
4187                 /* The difference between curr_events and last_events
4188                  * will be affected by any new non-sync IO (making
4189                  * curr_events bigger) and any difference in the amount of
4190                  * in-flight syncio (making current_events bigger or smaller)
4191                  * The amount in-flight is currently limited to
4192                  * 32*64K in raid1/10 and 256*PAGE_SIZE in raid5/6
4193                  * which is at most 4096 sectors.
4194                  * These numbers are fairly fragile and should be made
4195                  * more robust, probably by enforcing the
4196                  * 'window size' that md_do_sync sort-of uses.
4197                  *
4198                  * Note: the following is an unsigned comparison.
4199                  */
4200                 if ((curr_events - rdev->last_events + 4096) > 8192) {
4201                         rdev->last_events = curr_events;
4202                         idle = 0;
4203                 }
4204         }
4205         return idle;
4206 }
4207
4208 void md_done_sync(mddev_t *mddev, int blocks, int ok)
4209 {
4210         /* another "blocks" (512byte) blocks have been synced */
4211         atomic_sub(blocks, &mddev->recovery_active);
4212         wake_up(&mddev->recovery_wait);
4213         if (!ok) {
4214                 set_bit(MD_RECOVERY_ERR, &mddev->recovery);
4215                 md_wakeup_thread(mddev->thread);
4216                 // stop recovery, signal do_sync ....
4217         }
4218 }
4219
4220
4221 /* md_write_start(mddev, bi)
4222  * If we need to update some array metadata (e.g. 'active' flag
4223  * in superblock) before writing, schedule a superblock update
4224  * and wait for it to complete.
4225  */
4226 void md_write_start(mddev_t *mddev, struct bio *bi)
4227 {
4228         if (bio_data_dir(bi) != WRITE)
4229                 return;
4230
4231         BUG_ON(mddev->ro == 1);
4232         if (mddev->ro == 2) {
4233                 /* need to switch to read/write */
4234                 mddev->ro = 0;
4235                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4236                 md_wakeup_thread(mddev->thread);
4237         }
4238         atomic_inc(&mddev->writes_pending);
4239         if (mddev->in_sync) {
4240                 spin_lock_irq(&mddev->write_lock);
4241                 if (mddev->in_sync) {
4242                         mddev->in_sync = 0;
4243                         mddev->sb_dirty = 1;
4244                         md_wakeup_thread(mddev->thread);
4245                 }
4246                 spin_unlock_irq(&mddev->write_lock);
4247         }
4248         wait_event(mddev->sb_wait, mddev->sb_dirty==0);
4249 }
4250
4251 void md_write_end(mddev_t *mddev)
4252 {
4253         if (atomic_dec_and_test(&mddev->writes_pending)) {
4254                 if (mddev->safemode == 2)
4255                         md_wakeup_thread(mddev->thread);
4256                 else
4257                         mod_timer(&mddev->safemode_timer, jiffies + mddev->safemode_delay);
4258         }
4259 }
4260
4261 static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
4262
4263 #define SYNC_MARKS      10
4264 #define SYNC_MARK_STEP  (3*HZ)
4265 static void md_do_sync(mddev_t *mddev)
4266 {
4267         mddev_t *mddev2;
4268         unsigned int currspeed = 0,
4269                  window;
4270         sector_t max_sectors,j, io_sectors;
4271         unsigned long mark[SYNC_MARKS];
4272         sector_t mark_cnt[SYNC_MARKS];
4273         int last_mark,m;
4274         struct list_head *tmp;
4275         sector_t last_check;
4276         int skipped = 0;
4277
4278         /* just incase thread restarts... */
4279         if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
4280                 return;
4281
4282         /* we overload curr_resync somewhat here.
4283          * 0 == not engaged in resync at all
4284          * 2 == checking that there is no conflict with another sync
4285          * 1 == like 2, but have yielded to allow conflicting resync to
4286          *              commense
4287          * other == active in resync - this many blocks
4288          *
4289          * Before starting a resync we must have set curr_resync to
4290          * 2, and then checked that every "conflicting" array has curr_resync
4291          * less than ours.  When we find one that is the same or higher
4292          * we wait on resync_wait.  To avoid deadlock, we reduce curr_resync
4293          * to 1 if we choose to yield (based arbitrarily on address of mddev structure).
4294          * This will mean we have to start checking from the beginning again.
4295          *
4296          */
4297
4298         do {
4299                 mddev->curr_resync = 2;
4300
4301         try_again:
4302                 if (kthread_should_stop()) {
4303                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
4304                         goto skip;
4305                 }
4306                 ITERATE_MDDEV(mddev2,tmp) {
4307                         if (mddev2 == mddev)
4308                                 continue;
4309                         if (mddev2->curr_resync &&
4310                             match_mddev_units(mddev,mddev2)) {
4311                                 DEFINE_WAIT(wq);
4312                                 if (mddev < mddev2 && mddev->curr_resync == 2) {
4313                                         /* arbitrarily yield */
4314                                         mddev->curr_resync = 1;
4315                                         wake_up(&resync_wait);
4316                                 }
4317                                 if (mddev > mddev2 && mddev->curr_resync == 1)
4318                                         /* no need to wait here, we can wait the next
4319                                          * time 'round when curr_resync == 2
4320                                          */
4321                                         continue;
4322                                 prepare_to_wait(&resync_wait, &wq, TASK_UNINTERRUPTIBLE);
4323                                 if (!kthread_should_stop() &&
4324                                     mddev2->curr_resync >= mddev->curr_resync) {
4325                                         printk(KERN_INFO "md: delaying resync of %s"
4326                                                " until %s has finished resync (they"
4327                                                " share one or more physical units)\n",
4328                                                mdname(mddev), mdname(mddev2));
4329                                         mddev_put(mddev2);
4330                                         schedule();
4331                                         finish_wait(&resync_wait, &wq);
4332                                         goto try_again;
4333                                 }
4334                                 finish_wait(&resync_wait, &wq);
4335                         }
4336                 }
4337         } while (mddev->curr_resync < 2);
4338
4339         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
4340                 /* resync follows the size requested by the personality,
4341                  * which defaults to physical size, but can be virtual size
4342                  */
4343                 max_sectors = mddev->resync_max_sectors;
4344                 mddev->resync_mismatches = 0;
4345         } else
4346                 /* recovery follows the physical size of devices */
4347                 max_sectors = mddev->size << 1;
4348
4349         printk(KERN_INFO "md: syncing RAID array %s\n", mdname(mddev));
4350         printk(KERN_INFO "md: minimum _guaranteed_ reconstruction speed:"
4351                 " %d KB/sec/disc.\n", sysctl_speed_limit_min);
4352         printk(KERN_INFO "md: using maximum available idle IO bandwidth "
4353                "(but not more than %d KB/sec) for reconstruction.\n",
4354                sysctl_speed_limit_max);
4355
4356         is_mddev_idle(mddev); /* this also initializes IO event counters */
4357         /* we don't use the checkpoint if there's a bitmap */
4358         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && !mddev->bitmap
4359             && ! test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
4360                 j = mddev->recovery_cp;
4361         else
4362                 j = 0;
4363         io_sectors = 0;
4364         for (m = 0; m < SYNC_MARKS; m++) {
4365                 mark[m] = jiffies;
4366                 mark_cnt[m] = io_sectors;
4367         }
4368         last_mark = 0;
4369         mddev->resync_mark = mark[last_mark];
4370         mddev->resync_mark_cnt = mark_cnt[last_mark];
4371
4372         /*
4373          * Tune reconstruction:
4374          */
4375         window = 32*(PAGE_SIZE/512);
4376         printk(KERN_INFO "md: using %dk window, over a total of %llu blocks.\n",
4377                 window/2,(unsigned long long) max_sectors/2);
4378
4379         atomic_set(&mddev->recovery_active, 0);
4380         init_waitqueue_head(&mddev->recovery_wait);
4381         last_check = 0;
4382
4383         if (j>2) {
4384                 printk(KERN_INFO
4385                         "md: resuming recovery of %s from checkpoint.\n",
4386                         mdname(mddev));
4387                 mddev->curr_resync = j;
4388         }
4389
4390         while (j < max_sectors) {
4391                 sector_t sectors;
4392
4393                 skipped = 0;
4394                 sectors = mddev->pers->sync_request(mddev, j, &skipped,
4395                                             currspeed < sysctl_speed_limit_min);
4396                 if (sectors == 0) {
4397                         set_bit(MD_RECOVERY_ERR, &mddev->recovery);
4398                         goto out;
4399                 }
4400
4401                 if (!skipped) { /* actual IO requested */
4402                         io_sectors += sectors;
4403                         atomic_add(sectors, &mddev->recovery_active);
4404                 }
4405
4406                 j += sectors;
4407                 if (j>1) mddev->curr_resync = j;
4408                 if (last_check == 0)
4409                         /* this is the earliers that rebuilt will be
4410                          * visible in /proc/mdstat
4411                          */
4412                         md_new_event(mddev);
4413
4414                 if (last_check + window > io_sectors || j == max_sectors)
4415                         continue;
4416
4417                 last_check = io_sectors;
4418
4419                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery) ||
4420                     test_bit(MD_RECOVERY_ERR, &mddev->recovery))
4421                         break;
4422
4423         repeat:
4424                 if (time_after_eq(jiffies, mark[last_mark] + SYNC_MARK_STEP )) {
4425                         /* step marks */
4426                         int next = (last_mark+1) % SYNC_MARKS;
4427
4428                         mddev->resync_mark = mark[next];
4429                         mddev->resync_mark_cnt = mark_cnt[next];
4430                         mark[next] = jiffies;
4431                         mark_cnt[next] = io_sectors - atomic_read(&mddev->recovery_active);
4432                         last_mark = next;
4433                 }
4434
4435
4436                 if (kthread_should_stop()) {
4437                         /*
4438                          * got a signal, exit.
4439                          */
4440                         printk(KERN_INFO
4441                                 "md: md_do_sync() got signal ... exiting\n");
4442                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
4443                         goto out;
4444                 }
4445
4446                 /*
4447                  * this loop exits only if either when we are slower than
4448                  * the 'hard' speed limit, or the system was IO-idle for
4449                  * a jiffy.
4450                  * the system might be non-idle CPU-wise, but we only care
4451                  * about not overloading the IO subsystem. (things like an
4452                  * e2fsck being done on the RAID array should execute fast)
4453                  */
4454                 mddev->queue->unplug_fn(mddev->queue);
4455                 cond_resched();
4456
4457                 currspeed = ((unsigned long)(io_sectors-mddev->resync_mark_cnt))/2
4458                         /((jiffies-mddev->resync_mark)/HZ +1) +1;
4459
4460                 if (currspeed > sysctl_speed_limit_min) {
4461                         if ((currspeed > sysctl_speed_limit_max) ||
4462                                         !is_mddev_idle(mddev)) {
4463                                 msleep(500);
4464                                 goto repeat;
4465                         }
4466                 }
4467         }
4468         printk(KERN_INFO "md: %s: sync done.\n",mdname(mddev));
4469         /*
4470          * this also signals 'finished resyncing' to md_stop
4471          */
4472  out:
4473         mddev->queue->unplug_fn(mddev->queue);
4474
4475         wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
4476
4477         /* tell personality that we are finished */
4478         mddev->pers->sync_request(mddev, max_sectors, &skipped, 1);
4479
4480         if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
4481             mddev->curr_resync > 2 &&
4482             mddev->curr_resync >= mddev->recovery_cp) {
4483                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
4484                         printk(KERN_INFO
4485                                 "md: checkpointing recovery of %s.\n",
4486                                 mdname(mddev));
4487                         mddev->recovery_cp = mddev->curr_resync;
4488                 } else
4489                         mddev->recovery_cp = MaxSector;
4490         }
4491
4492  skip:
4493         mddev->curr_resync = 0;
4494         wake_up(&resync_wait);
4495         set_bit(MD_RECOVERY_DONE, &mddev->recovery);
4496         md_wakeup_thread(mddev->thread);
4497 }
4498
4499
4500 /*
4501  * This routine is regularly called by all per-raid-array threads to
4502  * deal with generic issues like resync and super-block update.
4503  * Raid personalities that don't have a thread (linear/raid0) do not
4504  * need this as they never do any recovery or update the superblock.
4505  *
4506  * It does not do any resync itself, but rather "forks" off other threads
4507  * to do that as needed.
4508  * When it is determined that resync is needed, we set MD_RECOVERY_RUNNING in
4509  * "->recovery" and create a thread at ->sync_thread.
4510  * When the thread finishes it sets MD_RECOVERY_DONE (and might set MD_RECOVERY_ERR)
4511  * and wakeups up this thread which will reap the thread and finish up.
4512  * This thread also removes any faulty devices (with nr_pending == 0).
4513  *
4514  * The overall approach is:
4515  *  1/ if the superblock needs updating, update it.
4516  *  2/ If a recovery thread is running, don't do anything else.
4517  *  3/ If recovery has finished, clean up, possibly marking spares active.
4518  *  4/ If there are any faulty devices, remove them.
4519  *  5/ If array is degraded, try to add spares devices
4520  *  6/ If array has spares or is not in-sync, start a resync thread.
4521  */
4522 void md_check_recovery(mddev_t *mddev)
4523 {
4524         mdk_rdev_t *rdev;
4525         struct list_head *rtmp;
4526
4527
4528         if (mddev->bitmap)
4529                 bitmap_daemon_work(mddev->bitmap);
4530
4531         if (mddev->ro)
4532                 return;
4533
4534         if (signal_pending(current)) {
4535                 if (mddev->pers->sync_request) {
4536                         printk(KERN_INFO "md: %s in immediate safe mode\n",
4537                                mdname(mddev));
4538                         mddev->safemode = 2;
4539                 }
4540                 flush_signals(current);
4541         }
4542
4543         if ( ! (
4544                 mddev->sb_dirty ||
4545                 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
4546                 test_bit(MD_RECOVERY_DONE, &mddev->recovery) ||
4547                 (mddev->safemode == 1) ||
4548                 (mddev->safemode == 2 && ! atomic_read(&mddev->writes_pending)
4549                  && !mddev->in_sync && mddev->recovery_cp == MaxSector)
4550                 ))
4551                 return;
4552
4553         if (mddev_trylock(mddev)==0) {
4554                 int spares =0;
4555
4556                 spin_lock_irq(&mddev->write_lock);
4557                 if (mddev->safemode && !atomic_read(&mddev->writes_pending) &&
4558                     !mddev->in_sync && mddev->recovery_cp == MaxSector) {
4559                         mddev->in_sync = 1;
4560                         mddev->sb_dirty = 1;
4561                 }
4562                 if (mddev->safemode == 1)
4563                         mddev->safemode = 0;
4564                 spin_unlock_irq(&mddev->write_lock);
4565
4566                 if (mddev->sb_dirty)
4567                         md_update_sb(mddev);
4568
4569
4570                 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
4571                     !test_bit(MD_RECOVERY_DONE, &mddev->recovery)) {
4572                         /* resync/recovery still happening */
4573                         clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4574                         goto unlock;
4575                 }
4576                 if (mddev->sync_thread) {
4577                         /* resync has finished, collect result */
4578                         md_unregister_thread(mddev->sync_thread);
4579                         mddev->sync_thread = NULL;
4580                         if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
4581                             !test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
4582                                 /* success...*/
4583                                 /* activate any spares */
4584                                 mddev->pers->spare_active(mddev);
4585                         }
4586                         md_update_sb(mddev);
4587
4588                         /* if array is no-longer degraded, then any saved_raid_disk
4589                          * information must be scrapped
4590                          */
4591                         if (!mddev->degraded)
4592                                 ITERATE_RDEV(mddev,rdev,rtmp)
4593                                         rdev->saved_raid_disk = -1;
4594
4595                         mddev->recovery = 0;
4596                         /* flag recovery needed just to double check */
4597                         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4598                         md_new_event(mddev);
4599                         goto unlock;
4600                 }
4601                 /* Clear some bits that don't mean anything, but
4602                  * might be left set
4603                  */
4604                 clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4605                 clear_bit(MD_RECOVERY_ERR, &mddev->recovery);
4606                 clear_bit(MD_RECOVERY_INTR, &mddev->recovery);
4607                 clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
4608
4609                 /* no recovery is running.
4610                  * remove any failed drives, then
4611                  * add spares if possible.
4612                  * Spare are also removed and re-added, to allow
4613                  * the personality to fail the re-add.
4614                  */
4615                 ITERATE_RDEV(mddev,rdev,rtmp)
4616                         if (rdev->raid_disk >= 0 &&
4617                             (test_bit(Faulty, &rdev->flags) || ! test_bit(In_sync, &rdev->flags)) &&
4618                             atomic_read(&rdev->nr_pending)==0) {
4619                                 if (mddev->pers->hot_remove_disk(mddev, rdev->raid_disk)==0) {
4620                                         char nm[20];
4621                                         sprintf(nm,"rd%d", rdev->raid_disk);
4622                                         sysfs_remove_link(&mddev->kobj, nm);
4623                                         rdev->raid_disk = -1;
4624                                 }
4625                         }
4626
4627                 if (mddev->degraded) {
4628                         ITERATE_RDEV(mddev,rdev,rtmp)
4629                                 if (rdev->raid_disk < 0
4630                                     && !test_bit(Faulty, &rdev->flags)) {
4631                                         if (mddev->pers->hot_add_disk(mddev,rdev)) {
4632                                                 char nm[20];
4633                                                 sprintf(nm, "rd%d", rdev->raid_disk);
4634                                                 sysfs_create_link(&mddev->kobj, &rdev->kobj, nm);
4635                                                 spares++;
4636                                                 md_new_event(mddev);
4637                                         } else
4638                                                 break;
4639                                 }
4640                 }
4641
4642                 if (spares) {
4643                         clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
4644                         clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
4645                 } else if (mddev->recovery_cp < MaxSector) {
4646                         set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
4647                 } else if (!test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
4648                         /* nothing to be done ... */
4649                         goto unlock;
4650
4651                 if (mddev->pers->sync_request) {
4652                         set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
4653                         if (spares && mddev->bitmap && ! mddev->bitmap->file) {
4654                                 /* We are adding a device or devices to an array
4655                                  * which has the bitmap stored on all devices.
4656                                  * So make sure all bitmap pages get written
4657                                  */
4658                                 bitmap_write_all(mddev->bitmap);
4659                         }
4660                         mddev->sync_thread = md_register_thread(md_do_sync,
4661                                                                 mddev,
4662                                                                 "%s_resync");
4663                         if (!mddev->sync_thread) {
4664                                 printk(KERN_ERR "%s: could not start resync"
4665                                         " thread...\n",
4666                                         mdname(mddev));
4667                                 /* leave the spares where they are, it shouldn't hurt */
4668                                 mddev->recovery = 0;
4669                         } else
4670                                 md_wakeup_thread(mddev->sync_thread);
4671                         md_new_event(mddev);
4672                 }
4673         unlock:
4674                 mddev_unlock(mddev);
4675         }
4676 }
4677
4678 static int md_notify_reboot(struct notifier_block *this,
4679                             unsigned long code, void *x)
4680 {
4681         struct list_head *tmp;
4682         mddev_t *mddev;
4683
4684         if ((code == SYS_DOWN) || (code == SYS_HALT) || (code == SYS_POWER_OFF)) {
4685
4686                 printk(KERN_INFO "md: stopping all md devices.\n");
4687
4688                 ITERATE_MDDEV(mddev,tmp)
4689                         if (mddev_trylock(mddev)==0)
4690                                 do_md_stop (mddev, 1);
4691                 /*
4692                  * certain more exotic SCSI devices are known to be
4693                  * volatile wrt too early system reboots. While the
4694                  * right place to handle this issue is the given
4695                  * driver, we do want to have a safe RAID driver ...
4696                  */
4697                 mdelay(1000*1);
4698         }
4699         return NOTIFY_DONE;
4700 }
4701
4702 static struct notifier_block md_notifier = {
4703         .notifier_call  = md_notify_reboot,
4704         .next           = NULL,
4705         .priority       = INT_MAX, /* before any real devices */
4706 };
4707
4708 static void md_geninit(void)
4709 {
4710         struct proc_dir_entry *p;
4711
4712         dprintk("md: sizeof(mdp_super_t) = %d\n", (int)sizeof(mdp_super_t));
4713
4714         p = create_proc_entry("mdstat", S_IRUGO, NULL);
4715         if (p)
4716                 p->proc_fops = &md_seq_fops;
4717 }
4718
4719 static int __init md_init(void)
4720 {
4721         int minor;
4722
4723         printk(KERN_INFO "md: md driver %d.%d.%d MAX_MD_DEVS=%d,"
4724                         " MD_SB_DISKS=%d\n",
4725                         MD_MAJOR_VERSION, MD_MINOR_VERSION,
4726                         MD_PATCHLEVEL_VERSION, MAX_MD_DEVS, MD_SB_DISKS);
4727         printk(KERN_INFO "md: bitmap version %d.%d\n", BITMAP_MAJOR_HI,
4728                         BITMAP_MINOR);
4729
4730         if (register_blkdev(MAJOR_NR, "md"))
4731                 return -1;
4732         if ((mdp_major=register_blkdev(0, "mdp"))<=0) {
4733                 unregister_blkdev(MAJOR_NR, "md");
4734                 return -1;
4735         }
4736         devfs_mk_dir("md");
4737         blk_register_region(MKDEV(MAJOR_NR, 0), MAX_MD_DEVS, THIS_MODULE,
4738                                 md_probe, NULL, NULL);
4739         blk_register_region(MKDEV(mdp_major, 0), MAX_MD_DEVS<<MdpMinorShift, THIS_MODULE,
4740                             md_probe, NULL, NULL);
4741
4742         for (minor=0; minor < MAX_MD_DEVS; ++minor)
4743                 devfs_mk_bdev(MKDEV(MAJOR_NR, minor),
4744                                 S_IFBLK|S_IRUSR|S_IWUSR,
4745                                 "md/%d", minor);
4746
4747         for (minor=0; minor < MAX_MD_DEVS; ++minor)
4748                 devfs_mk_bdev(MKDEV(mdp_major, minor<<MdpMinorShift),
4749                               S_IFBLK|S_IRUSR|S_IWUSR,
4750                               "md/mdp%d", minor);
4751
4752
4753         register_reboot_notifier(&md_notifier);
4754         raid_table_header = register_sysctl_table(raid_root_table, 1);
4755
4756         md_geninit();
4757         return (0);
4758 }
4759
4760
4761 #ifndef MODULE
4762
4763 /*
4764  * Searches all registered partitions for autorun RAID arrays
4765  * at boot time.
4766  */
4767 static dev_t detected_devices[128];
4768 static int dev_cnt;
4769
4770 void md_autodetect_dev(dev_t dev)
4771 {
4772         if (dev_cnt >= 0 && dev_cnt < 127)
4773                 detected_devices[dev_cnt++] = dev;
4774 }
4775
4776
4777 static void autostart_arrays(int part)
4778 {
4779         mdk_rdev_t *rdev;
4780         int i;
4781
4782         printk(KERN_INFO "md: Autodetecting RAID arrays.\n");
4783
4784         for (i = 0; i < dev_cnt; i++) {
4785                 dev_t dev = detected_devices[i];
4786
4787                 rdev = md_import_device(dev,0, 0);
4788                 if (IS_ERR(rdev))
4789                         continue;
4790
4791                 if (test_bit(Faulty, &rdev->flags)) {
4792                         MD_BUG();
4793                         continue;
4794                 }
4795                 list_add(&rdev->same_set, &pending_raid_disks);
4796         }
4797         dev_cnt = 0;
4798
4799         autorun_devices(part);
4800 }
4801
4802 #endif
4803
4804 static __exit void md_exit(void)
4805 {
4806         mddev_t *mddev;
4807         struct list_head *tmp;
4808         int i;
4809         blk_unregister_region(MKDEV(MAJOR_NR,0), MAX_MD_DEVS);
4810         blk_unregister_region(MKDEV(mdp_major,0), MAX_MD_DEVS << MdpMinorShift);
4811         for (i=0; i < MAX_MD_DEVS; i++)
4812                 devfs_remove("md/%d", i);
4813         for (i=0; i < MAX_MD_DEVS; i++)
4814                 devfs_remove("md/d%d", i);
4815
4816         devfs_remove("md");
4817
4818         unregister_blkdev(MAJOR_NR,"md");
4819         unregister_blkdev(mdp_major, "mdp");
4820         unregister_reboot_notifier(&md_notifier);
4821         unregister_sysctl_table(raid_table_header);
4822         remove_proc_entry("mdstat", NULL);
4823         ITERATE_MDDEV(mddev,tmp) {
4824                 struct gendisk *disk = mddev->gendisk;
4825                 if (!disk)
4826                         continue;
4827                 export_array(mddev);
4828                 del_gendisk(disk);
4829                 put_disk(disk);
4830                 mddev->gendisk = NULL;
4831                 mddev_put(mddev);
4832         }
4833 }
4834
4835 module_init(md_init)
4836 module_exit(md_exit)
4837
4838 static int get_ro(char *buffer, struct kernel_param *kp)
4839 {
4840         return sprintf(buffer, "%d", start_readonly);
4841 }
4842 static int set_ro(const char *val, struct kernel_param *kp)
4843 {
4844         char *e;
4845         int num = simple_strtoul(val, &e, 10);
4846         if (*val && (*e == '\0' || *e == '\n')) {
4847                 start_readonly = num;
4848                 return 0;
4849         }
4850         return -EINVAL;
4851 }
4852
4853 module_param_call(start_ro, set_ro, get_ro, NULL, 0600);
4854 module_param(start_dirty_degraded, int, 0644);
4855
4856
4857 EXPORT_SYMBOL(register_md_personality);
4858 EXPORT_SYMBOL(unregister_md_personality);
4859 EXPORT_SYMBOL(md_error);
4860 EXPORT_SYMBOL(md_done_sync);
4861 EXPORT_SYMBOL(md_write_start);
4862 EXPORT_SYMBOL(md_write_end);
4863 EXPORT_SYMBOL(md_register_thread);
4864 EXPORT_SYMBOL(md_unregister_thread);
4865 EXPORT_SYMBOL(md_wakeup_thread);
4866 EXPORT_SYMBOL(md_print_devices);
4867 EXPORT_SYMBOL(md_check_recovery);
4868 MODULE_LICENSE("GPL");
4869 MODULE_ALIAS("md");
4870 MODULE_ALIAS_BLOCKDEV_MAJOR(MD_MAJOR);