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 #include <linux/mutex.h>
  47
  48 #include <linux/init.h>
  49
  50 #include <linux/file.h>
  51
  52 #ifdef CONFIG_KMOD
  53 #include <linux/kmod.h>
  54 #endif
  55
  56 #include <asm/unaligned.h>
  57
  58 #define MAJOR_NR MD_MAJOR
  59 #define MD_DRIVER
  60
  61 /* 63 partitions with the alternate major number (mdp) */
  62 #define MdpMinorShift 6
  63
  64 #define DEBUG 0
  65 #define dprintk(x...) ((void)(DEBUG && printk(x)))
  66
  67
  68 #ifndef MODULE
  69 static void autostart_arrays (int part);
  70 #endif
  71
  72 static LIST_HEAD(pers_list);
  73 static DEFINE_SPINLOCK(pers_lock);
  74
  75 /*
  76  * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
  77  * is 1000 KB/sec, so the extra system load does not show up that much.
  78  * Increase it if you want to have more _guaranteed_ speed. Note that
  79  * the RAID driver will use the maximum available bandwidth if the IO
  80  * subsystem is idle. There is also an 'absolute maximum' reconstruction
  81  * speed limit - in case reconstruction slows down your system despite
  82  * idle IO detection.
  83  *
  84  * you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
  85  * or /sys/block/mdX/md/sync_speed_{min,max}
  86  */
  87
  88 static int sysctl_speed_limit_min = 1000;
  89 static int sysctl_speed_limit_max = 200000;
  90 static inline int speed_min(mddev_t *mddev)
  91 {
  92         return mddev->sync_speed_min ?
  93                 mddev->sync_speed_min : sysctl_speed_limit_min;
  94 }
  95
  96 static inline int speed_max(mddev_t *mddev)
  97 {
  98         return mddev->sync_speed_max ?
  99                 mddev->sync_speed_max : sysctl_speed_limit_max;
 100 }
 101
 102 static struct ctl_table_header *raid_table_header;
 103
 104 static ctl_table raid_table[] = {
 105         {
 106                 .ctl_name       = DEV_RAID_SPEED_LIMIT_MIN,
 107                 .procname       = "speed_limit_min",
 108                 .data           = &sysctl_speed_limit_min,
 109                 .maxlen         = sizeof(int),
 110                 .mode           = 0644,
 111                 .proc_handler   = &proc_dointvec,
 112         },
 113         {
 114                 .ctl_name       = DEV_RAID_SPEED_LIMIT_MAX,
 115                 .procname       = "speed_limit_max",
 116                 .data           = &sysctl_speed_limit_max,
 117                 .maxlen         = sizeof(int),
 118                 .mode           = 0644,
 119                 .proc_handler   = &proc_dointvec,
 120         },
 121         { .ctl_name = 0 }
 122 };
 123
 124 static ctl_table raid_dir_table[] = {
 125         {
 126                 .ctl_name       = DEV_RAID,
 127                 .procname       = "raid",
 128                 .maxlen         = 0,
 129                 .mode           = 0555,
 130                 .child          = raid_table,
 131         },
 132         { .ctl_name = 0 }
 133 };
 134
 135 static ctl_table raid_root_table[] = {
 136         {
 137                 .ctl_name       = CTL_DEV,
 138                 .procname       = "dev",
 139                 .maxlen         = 0,
 140                 .mode           = 0555,
 141                 .child          = raid_dir_table,
 142         },
 143         { .ctl_name = 0 }
 144 };
 145
 146 static struct block_device_operations md_fops;
 147
 148 static int start_readonly;
 149
 150 /*
 151  * We have a system wide 'event count' that is incremented
 152  * on any 'interesting' event, and readers of /proc/mdstat
 153  * can use 'poll' or 'select' to find out when the event
 154  * count increases.
 155  *
 156  * Events are:
 157  *  start array, stop array, error, add device, remove device,
 158  *  start build, activate spare
 159  */
 160 static DECLARE_WAIT_QUEUE_HEAD(md_event_waiters);
 161 static atomic_t md_event_count;
 162 void md_new_event(mddev_t *mddev)
 163 {
 164         atomic_inc(&md_event_count);
 165         wake_up(&md_event_waiters);
 166         sysfs_notify(&mddev->kobj, NULL, "sync_action");
 167 }
 168 EXPORT_SYMBOL_GPL(md_new_event);
 169
 170 /* Alternate version that can be called from interrupts
 171  * when calling sysfs_notify isn't needed.
 172  */
 173 void md_new_event_inintr(mddev_t *mddev)
 174 {
 175         atomic_inc(&md_event_count);
 176         wake_up(&md_event_waiters);
 177 }
 178
 179 /*
 180  * Enables to iterate over all existing md arrays
 181  * all_mddevs_lock protects this list.
 182  */
 183 static LIST_HEAD(all_mddevs);
 184 static DEFINE_SPINLOCK(all_mddevs_lock);
 185
 186
 187 /*
 188  * iterates through all used mddevs in the system.
 189  * We take care to grab the all_mddevs_lock whenever navigating
 190  * the list, and to always hold a refcount when unlocked.
 191  * Any code which breaks out of this loop while own
 192  * a reference to the current mddev and must mddev_put it.
 193  */
 194 #define ITERATE_MDDEV(mddev,tmp)                                        \
 195                                                                         \
 196         for (({ spin_lock(&all_mddevs_lock);                            \
 197                 tmp = all_mddevs.next;                                  \
 198                 mddev = NULL;});                                        \
 199              ({ if (tmp != &all_mddevs)                                 \
 200                         mddev_get(list_entry(tmp, mddev_t, all_mddevs));\
 201                 spin_unlock(&all_mddevs_lock);                          \
 202                 if (mddev) mddev_put(mddev);                            \
 203                 mddev = list_entry(tmp, mddev_t, all_mddevs);           \
 204                 tmp != &all_mddevs;});                                  \
 205              ({ spin_lock(&all_mddevs_lock);                            \
 206                 tmp = tmp->next;})                                      \
 207                 )
 208
 209
 210 static int md_fail_request (request_queue_t *q, struct bio *bio)
 211 {
 212         bio_io_error(bio, bio->bi_size);
 213         return 0;
 214 }
 215
 216 static inline mddev_t *mddev_get(mddev_t *mddev)
 217 {
 218         atomic_inc(&mddev->active);
 219         return mddev;
 220 }
 221
 222 static void mddev_put(mddev_t *mddev)
 223 {
 224         if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
 225                 return;
 226         if (!mddev->raid_disks && list_empty(&mddev->disks)) {
 227                 list_del(&mddev->all_mddevs);
 228                 spin_unlock(&all_mddevs_lock);
 229                 blk_cleanup_queue(mddev->queue);
 230                 kobject_unregister(&mddev->kobj);
 231         } else
 232                 spin_unlock(&all_mddevs_lock);
 233 }
 234
 235 static mddev_t * mddev_find(dev_t unit)
 236 {
 237         mddev_t *mddev, *new = NULL;
 238
 239  retry:
 240         spin_lock(&all_mddevs_lock);
 241         list_for_each_entry(mddev, &all_mddevs, all_mddevs)
 242                 if (mddev->unit == unit) {
 243                         mddev_get(mddev);
 244                         spin_unlock(&all_mddevs_lock);
 245                         kfree(new);
 246                         return mddev;
 247                 }
 248
 249         if (new) {
 250                 list_add(&new->all_mddevs, &all_mddevs);
 251                 spin_unlock(&all_mddevs_lock);
 252                 return new;
 253         }
 254         spin_unlock(&all_mddevs_lock);
 255
 256         new = kzalloc(sizeof(*new), GFP_KERNEL);
 257         if (!new)
 258                 return NULL;
 259
 260         new->unit = unit;
 261         if (MAJOR(unit) == MD_MAJOR)
 262                 new->md_minor = MINOR(unit);
 263         else
 264                 new->md_minor = MINOR(unit) >> MdpMinorShift;
 265
 266         mutex_init(&new->reconfig_mutex);
 267         INIT_LIST_HEAD(&new->disks);
 268         INIT_LIST_HEAD(&new->all_mddevs);
 269         init_timer(&new->safemode_timer);
 270         atomic_set(&new->active, 1);
 271         spin_lock_init(&new->write_lock);
 272         init_waitqueue_head(&new->sb_wait);
 273
 274         new->queue = blk_alloc_queue(GFP_KERNEL);
 275         if (!new->queue) {
 276                 kfree(new);
 277                 return NULL;
 278         }
 279         set_bit(QUEUE_FLAG_CLUSTER, &new->queue->queue_flags);
 280
 281         blk_queue_make_request(new->queue, md_fail_request);
 282
 283         goto retry;
 284 }
 285
 286 static inline int mddev_lock(mddev_t * mddev)
 287 {
 288         return mutex_lock_interruptible(&mddev->reconfig_mutex);
 289 }
 290
 291 static inline int mddev_trylock(mddev_t * mddev)
 292 {
 293         return mutex_trylock(&mddev->reconfig_mutex);
 294 }
 295
 296 static inline void mddev_unlock(mddev_t * mddev)
 297 {
 298         mutex_unlock(&mddev->reconfig_mutex);
 299
 300         md_wakeup_thread(mddev->thread);
 301 }
 302
 303 static mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr)
 304 {
 305         mdk_rdev_t * rdev;
 306         struct list_head *tmp;
 307
 308         ITERATE_RDEV(mddev,rdev,tmp) {
 309                 if (rdev->desc_nr == nr)
 310                         return rdev;
 311         }
 312         return NULL;
 313 }
 314
 315 static mdk_rdev_t * find_rdev(mddev_t * mddev, dev_t dev)
 316 {
 317         struct list_head *tmp;
 318         mdk_rdev_t *rdev;
 319
 320         ITERATE_RDEV(mddev,rdev,tmp) {
 321                 if (rdev->bdev->bd_dev == dev)
 322                         return rdev;
 323         }
 324         return NULL;
 325 }
 326
 327 static struct mdk_personality *find_pers(int level, char *clevel)
 328 {
 329         struct mdk_personality *pers;
 330         list_for_each_entry(pers, &pers_list, list) {
 331                 if (level != LEVEL_NONE && pers->level == level)
 332                         return pers;
 333                 if (strcmp(pers->name, clevel)==0)
 334                         return pers;
 335         }
 336         return NULL;
 337 }
 338
 339 static inline sector_t calc_dev_sboffset(struct block_device *bdev)
 340 {
 341         sector_t size = bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
 342         return MD_NEW_SIZE_BLOCKS(size);
 343 }
 344
 345 static sector_t calc_dev_size(mdk_rdev_t *rdev, unsigned chunk_size)
 346 {
 347         sector_t size;
 348
 349         size = rdev->sb_offset;
 350
 351         if (chunk_size)
 352                 size &= ~((sector_t)chunk_size/1024 - 1);
 353         return size;
 354 }
 355
 356 static int alloc_disk_sb(mdk_rdev_t * rdev)
 357 {
 358         if (rdev->sb_page)
 359                 MD_BUG();
 360
 361         rdev->sb_page = alloc_page(GFP_KERNEL);
 362         if (!rdev->sb_page) {
 363                 printk(KERN_ALERT "md: out of memory.\n");
 364                 return -EINVAL;
 365         }
 366
 367         return 0;
 368 }
 369
 370 static void free_disk_sb(mdk_rdev_t * rdev)
 371 {
 372         if (rdev->sb_page) {
 373                 put_page(rdev->sb_page);
 374                 rdev->sb_loaded = 0;
 375                 rdev->sb_page = NULL;
 376                 rdev->sb_offset = 0;
 377                 rdev->size = 0;
 378         }
 379 }
 380
 381
 382 static int super_written(struct bio *bio, unsigned int bytes_done, int error)
 383 {
 384         mdk_rdev_t *rdev = bio->bi_private;
 385         mddev_t *mddev = rdev->mddev;
 386         if (bio->bi_size)
 387                 return 1;
 388
 389         if (error || !test_bit(BIO_UPTODATE, &bio->bi_flags))
 390                 md_error(mddev, rdev);
 391
 392         if (atomic_dec_and_test(&mddev->pending_writes))
 393                 wake_up(&mddev->sb_wait);
 394         bio_put(bio);
 395         return 0;
 396 }
 397
 398 static int super_written_barrier(struct bio *bio, unsigned int bytes_done, int error)
 399 {
 400         struct bio *bio2 = bio->bi_private;
 401         mdk_rdev_t *rdev = bio2->bi_private;
 402         mddev_t *mddev = rdev->mddev;
 403         if (bio->bi_size)
 404                 return 1;
 405
 406         if (!test_bit(BIO_UPTODATE, &bio->bi_flags) &&
 407             error == -EOPNOTSUPP) {
 408                 unsigned long flags;
 409                 /* barriers don't appear to be supported :-( */
 410                 set_bit(BarriersNotsupp, &rdev->flags);
 411                 mddev->barriers_work = 0;
 412                 spin_lock_irqsave(&mddev->write_lock, flags);
 413                 bio2->bi_next = mddev->biolist;
 414                 mddev->biolist = bio2;
 415                 spin_unlock_irqrestore(&mddev->write_lock, flags);
 416                 wake_up(&mddev->sb_wait);
 417                 bio_put(bio);
 418                 return 0;
 419         }
 420         bio_put(bio2);
 421         bio->bi_private = rdev;
 422         return super_written(bio, bytes_done, error);
 423 }
 424
 425 void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev,
 426                    sector_t sector, int size, struct page *page)
 427 {
 428         /* write first size bytes of page to sector of rdev
 429          * Increment mddev->pending_writes before returning
 430          * and decrement it on completion, waking up sb_wait
 431          * if zero is reached.
 432          * If an error occurred, call md_error
 433          *
 434          * As we might need to resubmit the request if BIO_RW_BARRIER
 435          * causes ENOTSUPP, we allocate a spare bio...
 436          */
 437         struct bio *bio = bio_alloc(GFP_NOIO, 1);
 438         int rw = (1<<BIO_RW) | (1<<BIO_RW_SYNC);
 439
 440         bio->bi_bdev = rdev->bdev;
 441         bio->bi_sector = sector;
 442         bio_add_page(bio, page, size, 0);
 443         bio->bi_private = rdev;
 444         bio->bi_end_io = super_written;
 445         bio->bi_rw = rw;
 446
 447         atomic_inc(&mddev->pending_writes);
 448         if (!test_bit(BarriersNotsupp, &rdev->flags)) {
 449                 struct bio *rbio;
 450                 rw |= (1<<BIO_RW_BARRIER);
 451                 rbio = bio_clone(bio, GFP_NOIO);
 452                 rbio->bi_private = bio;
 453                 rbio->bi_end_io = super_written_barrier;
 454                 submit_bio(rw, rbio);
 455         } else
 456                 submit_bio(rw, bio);
 457 }
 458
 459 void md_super_wait(mddev_t *mddev)
 460 {
 461         /* wait for all superblock writes that were scheduled to complete.
 462          * if any had to be retried (due to BARRIER problems), retry them
 463          */
 464         DEFINE_WAIT(wq);
 465         for(;;) {
 466                 prepare_to_wait(&mddev->sb_wait, &wq, TASK_UNINTERRUPTIBLE);
 467                 if (atomic_read(&mddev->pending_writes)==0)
 468                         break;
 469                 while (mddev->biolist) {
 470                         struct bio *bio;
 471                         spin_lock_irq(&mddev->write_lock);
 472                         bio = mddev->biolist;
 473                         mddev->biolist = bio->bi_next ;
 474                         bio->bi_next = NULL;
 475                         spin_unlock_irq(&mddev->write_lock);
 476                         submit_bio(bio->bi_rw, bio);
 477                 }
 478                 schedule();
 479         }
 480         finish_wait(&mddev->sb_wait, &wq);
 481 }
 482
 483 static int bi_complete(struct bio *bio, unsigned int bytes_done, int error)
 484 {
 485         if (bio->bi_size)
 486                 return 1;
 487
 488         complete((struct completion*)bio->bi_private);
 489         return 0;
 490 }
 491
 492 int sync_page_io(struct block_device *bdev, sector_t sector, int size,
 493                    struct page *page, int rw)
 494 {
 495         struct bio *bio = bio_alloc(GFP_NOIO, 1);
 496         struct completion event;
 497         int ret;
 498
 499         rw |= (1 << BIO_RW_SYNC);
 500
 501         bio->bi_bdev = bdev;
 502         bio->bi_sector = sector;
 503         bio_add_page(bio, page, size, 0);
 504         init_completion(&event);
 505         bio->bi_private = &event;
 506         bio->bi_end_io = bi_complete;
 507         submit_bio(rw, bio);
 508         wait_for_completion(&event);
 509
 510         ret = test_bit(BIO_UPTODATE, &bio->bi_flags);
 511         bio_put(bio);
 512         return ret;
 513 }
 514 EXPORT_SYMBOL_GPL(sync_page_io);
 515
 516 static int read_disk_sb(mdk_rdev_t * rdev, int size)
 517 {
 518         char b[BDEVNAME_SIZE];
 519         if (!rdev->sb_page) {
 520                 MD_BUG();
 521                 return -EINVAL;
 522         }
 523         if (rdev->sb_loaded)
 524                 return 0;
 525
 526
 527         if (!sync_page_io(rdev->bdev, rdev->sb_offset<<1, size, rdev->sb_page, READ))
 528                 goto fail;
 529         rdev->sb_loaded = 1;
 530         return 0;
 531
 532 fail:
 533         printk(KERN_WARNING "md: disabled device %s, could not read superblock.\n",
 534                 bdevname(rdev->bdev,b));
 535         return -EINVAL;
 536 }
 537
 538 static int uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 539 {
 540         if (    (sb1->set_uuid0 == sb2->set_uuid0) &&
 541                 (sb1->set_uuid1 == sb2->set_uuid1) &&
 542                 (sb1->set_uuid2 == sb2->set_uuid2) &&
 543                 (sb1->set_uuid3 == sb2->set_uuid3))
 544
 545                 return 1;
 546
 547         return 0;
 548 }
 549
 550
 551 static int sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 552 {
 553         int ret;
 554         mdp_super_t *tmp1, *tmp2;
 555
 556         tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
 557         tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
 558
 559         if (!tmp1 || !tmp2) {
 560                 ret = 0;
 561                 printk(KERN_INFO "md.c: sb1 is not equal to sb2!\n");
 562                 goto abort;
 563         }
 564
 565         *tmp1 = *sb1;
 566         *tmp2 = *sb2;
 567
 568         /*
 569          * nr_disks is not constant
 570          */
 571         tmp1->nr_disks = 0;
 572         tmp2->nr_disks = 0;
 573
 574         if (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4))
 575                 ret = 0;
 576         else
 577                 ret = 1;
 578
 579 abort:
 580         kfree(tmp1);
 581         kfree(tmp2);
 582         return ret;
 583 }
 584
 585 static unsigned int calc_sb_csum(mdp_super_t * sb)
 586 {
 587         unsigned int disk_csum, csum;
 588
 589         disk_csum = sb->sb_csum;
 590         sb->sb_csum = 0;
 591         csum = csum_partial((void *)sb, MD_SB_BYTES, 0);
 592         sb->sb_csum = disk_csum;
 593         return csum;
 594 }
 595
 596
 597 /*
 598  * Handle superblock details.
 599  * We want to be able to handle multiple superblock formats
 600  * so we have a common interface to them all, and an array of
 601  * different handlers.
 602  * We rely on user-space to write the initial superblock, and support
 603  * reading and updating of superblocks.
 604  * Interface methods are:
 605  *   int load_super(mdk_rdev_t *dev, mdk_rdev_t *refdev, int minor_version)
 606  *      loads and validates a superblock on dev.
 607  *      if refdev != NULL, compare superblocks on both devices
 608  *    Return:
 609  *      0 - dev has a superblock that is compatible with refdev
 610  *      1 - dev has a superblock that is compatible and newer than refdev
 611  *          so dev should be used as the refdev in future
 612  *     -EINVAL superblock incompatible or invalid
 613  *     -othererror e.g. -EIO
 614  *
 615  *   int validate_super(mddev_t *mddev, mdk_rdev_t *dev)
 616  *      Verify that dev is acceptable into mddev.
 617  *       The first time, mddev->raid_disks will be 0, and data from
 618  *       dev should be merged in.  Subsequent calls check that dev
 619  *       is new enough.  Return 0 or -EINVAL
 620  *
 621  *   void sync_super(mddev_t *mddev, mdk_rdev_t *dev)
 622  *     Update the superblock for rdev with data in mddev
 623  *     This does not write to disc.
 624  *
 625  */
 626
 627 struct super_type  {
 628         char            *name;
 629         struct module   *owner;
 630         int             (*load_super)(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version);
 631         int             (*validate_super)(mddev_t *mddev, mdk_rdev_t *rdev);
 632         void            (*sync_super)(mddev_t *mddev, mdk_rdev_t *rdev);
 633 };
 634
 635 /*
 636  * load_super for 0.90.0
 637  */
 638 static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
 639 {
 640         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
 641         mdp_super_t *sb;
 642         int ret;
 643         sector_t sb_offset;
 644
 645         /*
 646          * Calculate the position of the superblock,
 647          * it's at the end of the disk.
 648          *
 649          * It also happens to be a multiple of 4Kb.
 650          */
 651         sb_offset = calc_dev_sboffset(rdev->bdev);
 652         rdev->sb_offset = sb_offset;
 653
 654         ret = read_disk_sb(rdev, MD_SB_BYTES);
 655         if (ret) return ret;
 656
 657         ret = -EINVAL;
 658
 659         bdevname(rdev->bdev, b);
 660         sb = (mdp_super_t*)page_address(rdev->sb_page);
 661
 662         if (sb->md_magic != MD_SB_MAGIC) {
 663                 printk(KERN_ERR "md: invalid raid superblock magic on %s\n",
 664                        b);
 665                 goto abort;
 666         }
 667
 668         if (sb->major_version != 0 ||
 669             sb->minor_version < 90 ||
 670             sb->minor_version > 91) {
 671                 printk(KERN_WARNING "Bad version number %d.%d on %s\n",
 672                         sb->major_version, sb->minor_version,
 673                         b);
 674                 goto abort;
 675         }
 676
 677         if (sb->raid_disks <= 0)
 678                 goto abort;
 679
 680         if (csum_fold(calc_sb_csum(sb)) != csum_fold(sb->sb_csum)) {
 681                 printk(KERN_WARNING "md: invalid superblock checksum on %s\n",
 682                         b);
 683                 goto abort;
 684         }
 685
 686         rdev->preferred_minor = sb->md_minor;
 687         rdev->data_offset = 0;
 688         rdev->sb_size = MD_SB_BYTES;
 689
 690         if (sb->level == LEVEL_MULTIPATH)
 691                 rdev->desc_nr = -1;
 692         else
 693                 rdev->desc_nr = sb->this_disk.number;
 694
 695         if (refdev == 0)
 696                 ret = 1;
 697         else {
 698                 __u64 ev1, ev2;
 699                 mdp_super_t *refsb = (mdp_super_t*)page_address(refdev->sb_page);
 700                 if (!uuid_equal(refsb, sb)) {
 701                         printk(KERN_WARNING "md: %s has different UUID to %s\n",
 702                                 b, bdevname(refdev->bdev,b2));
 703                         goto abort;
 704                 }
 705                 if (!sb_equal(refsb, sb)) {
 706                         printk(KERN_WARNING "md: %s has same UUID"
 707                                " but different superblock to %s\n",
 708                                b, bdevname(refdev->bdev, b2));
 709                         goto abort;
 710                 }
 711                 ev1 = md_event(sb);
 712                 ev2 = md_event(refsb);
 713                 if (ev1 > ev2)
 714                         ret = 1;
 715                 else
 716                         ret = 0;
 717         }
 718         rdev->size = calc_dev_size(rdev, sb->chunk_size);
 719
 720         if (rdev->size < sb->size && sb->level > 1)
 721                 /* "this cannot possibly happen" ... */
 722                 ret = -EINVAL;
 723
 724  abort:
 725         return ret;
 726 }
 727
 728 /*
 729  * validate_super for 0.90.0
 730  */
 731 static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
 732 {
 733         mdp_disk_t *desc;
 734         mdp_super_t *sb = (mdp_super_t *)page_address(rdev->sb_page);
 735
 736         rdev->raid_disk = -1;
 737         rdev->flags = 0;
 738         if (mddev->raid_disks == 0) {
 739                 mddev->major_version = 0;
 740                 mddev->minor_version = sb->minor_version;
 741                 mddev->patch_version = sb->patch_version;
 742                 mddev->persistent = ! sb->not_persistent;
 743                 mddev->chunk_size = sb->chunk_size;
 744                 mddev->ctime = sb->ctime;
 745                 mddev->utime = sb->utime;
 746                 mddev->level = sb->level;
 747                 mddev->clevel[0] = 0;
 748                 mddev->layout = sb->layout;
 749                 mddev->raid_disks = sb->raid_disks;
 750                 mddev->size = sb->size;
 751                 mddev->events = md_event(sb);
 752                 mddev->bitmap_offset = 0;
 753                 mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
 754
 755                 if (mddev->minor_version >= 91) {
 756                         mddev->reshape_position = sb->reshape_position;
 757                         mddev->delta_disks = sb->delta_disks;
 758                         mddev->new_level = sb->new_level;
 759                         mddev->new_layout = sb->new_layout;
 760                         mddev->new_chunk = sb->new_chunk;
 761                 } else {
 762                         mddev->reshape_position = MaxSector;
 763                         mddev->delta_disks = 0;
 764                         mddev->new_level = mddev->level;
 765                         mddev->new_layout = mddev->layout;
 766                         mddev->new_chunk = mddev->chunk_size;
 767                 }
 768
 769                 if (sb->state & (1<<MD_SB_CLEAN))
 770                         mddev->recovery_cp = MaxSector;
 771                 else {
 772                         if (sb->events_hi == sb->cp_events_hi &&
 773                                 sb->events_lo == sb->cp_events_lo) {
 774                                 mddev->recovery_cp = sb->recovery_cp;
 775                         } else
 776                                 mddev->recovery_cp = 0;
 777                 }
 778
 779                 memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
 780                 memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
 781                 memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
 782                 memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
 783
 784                 mddev->max_disks = MD_SB_DISKS;
 785
 786                 if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
 787                     mddev->bitmap_file == NULL) {
 788                         if (mddev->level != 1 && mddev->level != 4
 789                             && mddev->level != 5 && mddev->level != 6
 790                             && mddev->level != 10) {
 791                                 /* FIXME use a better test */
 792                                 printk(KERN_WARNING "md: bitmaps not supported for this level.\n");
 793                                 return -EINVAL;
 794                         }
 795                         mddev->bitmap_offset = mddev->default_bitmap_offset;
 796                 }
 797
 798         } else if (mddev->pers == NULL) {
 799                 /* Insist on good event counter while assembling */
 800                 __u64 ev1 = md_event(sb);
 801                 ++ev1;
 802                 if (ev1 < mddev->events)
 803                         return -EINVAL;
 804         } else if (mddev->bitmap) {
 805                 /* if adding to array with a bitmap, then we can accept an
 806                  * older device ... but not too old.
 807                  */
 808                 __u64 ev1 = md_event(sb);
 809                 if (ev1 < mddev->bitmap->events_cleared)
 810                         return 0;
 811         } else /* just a hot-add of a new device, leave raid_disk at -1 */
 812                 return 0;
 813
 814         if (mddev->level != LEVEL_MULTIPATH) {
 815                 desc = sb->disks + rdev->desc_nr;
 816
 817                 if (desc->state & (1<<MD_DISK_FAULTY))
 818                         set_bit(Faulty, &rdev->flags);
 819                 else if (desc->state & (1<<MD_DISK_SYNC) &&
 820                          desc->raid_disk < mddev->raid_disks) {
 821                         set_bit(In_sync, &rdev->flags);
 822                         rdev->raid_disk = desc->raid_disk;
 823                 }
 824                 if (desc->state & (1<<MD_DISK_WRITEMOSTLY))
 825                         set_bit(WriteMostly, &rdev->flags);
 826         } else /* MULTIPATH are always insync */
 827                 set_bit(In_sync, &rdev->flags);
 828         return 0;
 829 }
 830
 831 /*
 832  * sync_super for 0.90.0
 833  */
 834 static void super_90_sync(mddev_t *mddev, mdk_rdev_t *rdev)
 835 {
 836         mdp_super_t *sb;
 837         struct list_head *tmp;
 838         mdk_rdev_t *rdev2;
 839         int next_spare = mddev->raid_disks;
 840
 841
 842         /* make rdev->sb match mddev data..
 843          *
 844          * 1/ zero out disks
 845          * 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
 846          * 3/ any empty disks < next_spare become removed
 847          *
 848          * disks[0] gets initialised to REMOVED because
 849          * we cannot be sure from other fields if it has
 850          * been initialised or not.
 851          */
 852         int i;
 853         int active=0, working=0,failed=0,spare=0,nr_disks=0;
 854
 855         rdev->sb_size = MD_SB_BYTES;
 856
 857         sb = (mdp_super_t*)page_address(rdev->sb_page);
 858
 859         memset(sb, 0, sizeof(*sb));
 860
 861         sb->md_magic = MD_SB_MAGIC;
 862         sb->major_version = mddev->major_version;
 863         sb->patch_version = mddev->patch_version;
 864         sb->gvalid_words  = 0; /* ignored */
 865         memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
 866         memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
 867         memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
 868         memcpy(&sb->set_uuid3, mddev->uuid+12,4);
 869
 870         sb->ctime = mddev->ctime;
 871         sb->level = mddev->level;
 872         sb->size  = mddev->size;
 873         sb->raid_disks = mddev->raid_disks;
 874         sb->md_minor = mddev->md_minor;
 875         sb->not_persistent = !mddev->persistent;
 876         sb->utime = mddev->utime;
 877         sb->state = 0;
 878         sb->events_hi = (mddev->events>>32);
 879         sb->events_lo = (u32)mddev->events;
 880
 881         if (mddev->reshape_position == MaxSector)
 882                 sb->minor_version = 90;
 883         else {
 884                 sb->minor_version = 91;
 885                 sb->reshape_position = mddev->reshape_position;
 886                 sb->new_level = mddev->new_level;
 887                 sb->delta_disks = mddev->delta_disks;
 888                 sb->new_layout = mddev->new_layout;
 889                 sb->new_chunk = mddev->new_chunk;
 890         }
 891         mddev->minor_version = sb->minor_version;
 892         if (mddev->in_sync)
 893         {
 894                 sb->recovery_cp = mddev->recovery_cp;
 895                 sb->cp_events_hi = (mddev->events>>32);
 896                 sb->cp_events_lo = (u32)mddev->events;
 897                 if (mddev->recovery_cp == MaxSector)
 898                         sb->state = (1<< MD_SB_CLEAN);
 899         } else
 900                 sb->recovery_cp = 0;
 901
 902         sb->layout = mddev->layout;
 903         sb->chunk_size = mddev->chunk_size;
 904
 905         if (mddev->bitmap && mddev->bitmap_file == NULL)
 906                 sb->state |= (1<<MD_SB_BITMAP_PRESENT);
 907
 908         sb->disks[0].state = (1<<MD_DISK_REMOVED);
 909         ITERATE_RDEV(mddev,rdev2,tmp) {
 910                 mdp_disk_t *d;
 911                 int desc_nr;
 912                 if (rdev2->raid_disk >= 0 && test_bit(In_sync, &rdev2->flags)
 913                     && !test_bit(Faulty, &rdev2->flags))
 914                         desc_nr = rdev2->raid_disk;
 915                 else
 916                         desc_nr = next_spare++;
 917                 rdev2->desc_nr = desc_nr;
 918                 d = &sb->disks[rdev2->desc_nr];
 919                 nr_disks++;
 920                 d->number = rdev2->desc_nr;
 921                 d->major = MAJOR(rdev2->bdev->bd_dev);
 922                 d->minor = MINOR(rdev2->bdev->bd_dev);
 923                 if (rdev2->raid_disk >= 0 && test_bit(In_sync, &rdev2->flags)
 924                     && !test_bit(Faulty, &rdev2->flags))
 925                         d->raid_disk = rdev2->raid_disk;
 926                 else
 927                         d->raid_disk = rdev2->desc_nr; /* compatibility */
 928                 if (test_bit(Faulty, &rdev2->flags))
 929                         d->state = (1<<MD_DISK_FAULTY);
 930                 else if (test_bit(In_sync, &rdev2->flags)) {
 931                         d->state = (1<<MD_DISK_ACTIVE);
 932                         d->state |= (1<<MD_DISK_SYNC);
 933                         active++;
 934                         working++;
 935                 } else {
 936                         d->state = 0;
 937                         spare++;
 938                         working++;
 939                 }
 940                 if (test_bit(WriteMostly, &rdev2->flags))
 941                         d->state |= (1<<MD_DISK_WRITEMOSTLY);
 942         }
 943         /* now set the "removed" and "faulty" bits on any missing devices */
 944         for (i=0 ; i < mddev->raid_disks ; i++) {
 945                 mdp_disk_t *d = &sb->disks[i];
 946                 if (d->state == 0 && d->number == 0) {
 947                         d->number = i;
 948                         d->raid_disk = i;
 949                         d->state = (1<<MD_DISK_REMOVED);
 950                         d->state |= (1<<MD_DISK_FAULTY);
 951                         failed++;
 952                 }
 953         }
 954         sb->nr_disks = nr_disks;
 955         sb->active_disks = active;
 956         sb->working_disks = working;
 957         sb->failed_disks = failed;
 958         sb->spare_disks = spare;
 959
 960         sb->this_disk = sb->disks[rdev->desc_nr];
 961         sb->sb_csum = calc_sb_csum(sb);
 962 }
 963
 964 /*
 965  * version 1 superblock
 966  */
 967
 968 static unsigned int calc_sb_1_csum(struct mdp_superblock_1 * sb)
 969 {
 970         unsigned int disk_csum, csum;
 971         unsigned long long newcsum;
 972         int size = 256 + le32_to_cpu(sb->max_dev)*2;
 973         unsigned int *isuper = (unsigned int*)sb;
 974         int i;
 975
 976         disk_csum = sb->sb_csum;
 977         sb->sb_csum = 0;
 978         newcsum = 0;
 979         for (i=0; size>=4; size -= 4 )
 980                 newcsum += le32_to_cpu(*isuper++);
 981
 982         if (size == 2)
 983                 newcsum += le16_to_cpu(*(unsigned short*) isuper);
 984
 985         csum = (newcsum & 0xffffffff) + (newcsum >> 32);
 986         sb->sb_csum = disk_csum;
 987         return cpu_to_le32(csum);
 988 }
 989
 990 static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
 991 {
 992         struct mdp_superblock_1 *sb;
 993         int ret;
 994         sector_t sb_offset;
 995         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
 996         int bmask;
 997
 998         /*
 999          * Calculate the position of the superblock.
1000          * It is always aligned to a 4K boundary and
1001          * depeding on minor_version, it can be:
1002          * 0: At least 8K, but less than 12K, from end of device
1003          * 1: At start of device
1004          * 2: 4K from start of device.
1005          */
1006         switch(minor_version) {
1007         case 0:
1008                 sb_offset = rdev->bdev->bd_inode->i_size >> 9;
1009                 sb_offset -= 8*2;
1010                 sb_offset &= ~(sector_t)(4*2-1);
1011                 /* convert from sectors to K */
1012                 sb_offset /= 2;
1013                 break;
1014         case 1:
1015                 sb_offset = 0;
1016                 break;
1017         case 2:
1018                 sb_offset = 4;
1019                 break;
1020         default:
1021                 return -EINVAL;
1022         }
1023         rdev->sb_offset = sb_offset;
1024
1025         /* superblock is rarely larger than 1K, but it can be larger,
1026          * and it is safe to read 4k, so we do that
1027          */
1028         ret = read_disk_sb(rdev, 4096);
1029         if (ret) return ret;
1030
1031
1032         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1033
1034         if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
1035             sb->major_version != cpu_to_le32(1) ||
1036             le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
1037             le64_to_cpu(sb->super_offset) != (rdev->sb_offset<<1) ||
1038             (le32_to_cpu(sb->feature_map) & ~MD_FEATURE_ALL) != 0)
1039                 return -EINVAL;
1040
1041         if (calc_sb_1_csum(sb) != sb->sb_csum) {
1042                 printk("md: invalid superblock checksum on %s\n",
1043                         bdevname(rdev->bdev,b));
1044                 return -EINVAL;
1045         }
1046         if (le64_to_cpu(sb->data_size) < 10) {
1047                 printk("md: data_size too small on %s\n",
1048                        bdevname(rdev->bdev,b));
1049                 return -EINVAL;
1050         }
1051         rdev->preferred_minor = 0xffff;
1052         rdev->data_offset = le64_to_cpu(sb->data_offset);
1053         atomic_set(&rdev->corrected_errors, le32_to_cpu(sb->cnt_corrected_read));
1054
1055         rdev->sb_size = le32_to_cpu(sb->max_dev) * 2 + 256;
1056         bmask = queue_hardsect_size(rdev->bdev->bd_disk->queue)-1;
1057         if (rdev->sb_size & bmask)
1058                 rdev-> sb_size = (rdev->sb_size | bmask)+1;
1059
1060         if (refdev == 0)
1061                 ret = 1;
1062         else {
1063                 __u64 ev1, ev2;
1064                 struct mdp_superblock_1 *refsb =
1065                         (struct mdp_superblock_1*)page_address(refdev->sb_page);
1066
1067                 if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
1068                     sb->level != refsb->level ||
1069                     sb->layout != refsb->layout ||
1070                     sb->chunksize != refsb->chunksize) {
1071                         printk(KERN_WARNING "md: %s has strangely different"
1072                                 " superblock to %s\n",
1073                                 bdevname(rdev->bdev,b),
1074                                 bdevname(refdev->bdev,b2));
1075                         return -EINVAL;
1076                 }
1077                 ev1 = le64_to_cpu(sb->events);
1078                 ev2 = le64_to_cpu(refsb->events);
1079
1080                 if (ev1 > ev2)
1081                         ret = 1;
1082                 else
1083                         ret = 0;
1084         }
1085         if (minor_version)
1086                 rdev->size = ((rdev->bdev->bd_inode->i_size>>9) - le64_to_cpu(sb->data_offset)) / 2;
1087         else
1088                 rdev->size = rdev->sb_offset;
1089         if (rdev->size < le64_to_cpu(sb->data_size)/2)
1090                 return -EINVAL;
1091         rdev->size = le64_to_cpu(sb->data_size)/2;
1092         if (le32_to_cpu(sb->chunksize))
1093                 rdev->size &= ~((sector_t)le32_to_cpu(sb->chunksize)/2 - 1);
1094
1095         if (le32_to_cpu(sb->size) > rdev->size*2)
1096                 return -EINVAL;
1097         return ret;
1098 }
1099
1100 static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
1101 {
1102         struct mdp_superblock_1 *sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1103
1104         rdev->raid_disk = -1;
1105         rdev->flags = 0;
1106         if (mddev->raid_disks == 0) {
1107                 mddev->major_version = 1;
1108                 mddev->patch_version = 0;
1109                 mddev->persistent = 1;
1110                 mddev->chunk_size = le32_to_cpu(sb->chunksize) << 9;
1111                 mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);
1112                 mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);
1113                 mddev->level = le32_to_cpu(sb->level);
1114                 mddev->clevel[0] = 0;
1115                 mddev->layout = le32_to_cpu(sb->layout);
1116                 mddev->raid_disks = le32_to_cpu(sb->raid_disks);
1117                 mddev->size = le64_to_cpu(sb->size)/2;
1118                 mddev->events = le64_to_cpu(sb->events);
1119                 mddev->bitmap_offset = 0;
1120                 mddev->default_bitmap_offset = 1024 >> 9;
1121
1122                 mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
1123                 memcpy(mddev->uuid, sb->set_uuid, 16);
1124
1125                 mddev->max_disks =  (4096-256)/2;
1126
1127                 if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET) &&
1128                     mddev->bitmap_file == NULL ) {
1129                         if (mddev->level != 1 && mddev->level != 5 && mddev->level != 6
1130                             && mddev->level != 10) {
1131                                 printk(KERN_WARNING "md: bitmaps not supported for this level.\n");
1132                                 return -EINVAL;
1133                         }
1134                         mddev->bitmap_offset = (__s32)le32_to_cpu(sb->bitmap_offset);
1135                 }
1136                 if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE)) {
1137                         mddev->reshape_position = le64_to_cpu(sb->reshape_position);
1138                         mddev->delta_disks = le32_to_cpu(sb->delta_disks);
1139                         mddev->new_level = le32_to_cpu(sb->new_level);
1140                         mddev->new_layout = le32_to_cpu(sb->new_layout);
1141                         mddev->new_chunk = le32_to_cpu(sb->new_chunk)<<9;
1142                 } else {
1143                         mddev->reshape_position = MaxSector;
1144                         mddev->delta_disks = 0;
1145                         mddev->new_level = mddev->level;
1146                         mddev->new_layout = mddev->layout;
1147                         mddev->new_chunk = mddev->chunk_size;
1148                 }
1149
1150         } else if (mddev->pers == NULL) {
1151                 /* Insist of good event counter while assembling */
1152                 __u64 ev1 = le64_to_cpu(sb->events);
1153                 ++ev1;
1154                 if (ev1 < mddev->events)
1155                         return -EINVAL;
1156         } else if (mddev->bitmap) {
1157                 /* If adding to array with a bitmap, then we can accept an
1158                  * older device, but not too old.
1159                  */
1160                 __u64 ev1 = le64_to_cpu(sb->events);
1161                 if (ev1 < mddev->bitmap->events_cleared)
1162                         return 0;
1163         } else /* just a hot-add of a new device, leave raid_disk at -1 */
1164                 return 0;
1165
1166         if (mddev->level != LEVEL_MULTIPATH) {
1167                 int role;
1168                 rdev->desc_nr = le32_to_cpu(sb->dev_number);
1169                 role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
1170                 switch(role) {
1171                 case 0xffff: /* spare */
1172                         break;
1173                 case 0xfffe: /* faulty */
1174                         set_bit(Faulty, &rdev->flags);
1175                         break;
1176                 default:
1177                         set_bit(In_sync, &rdev->flags);
1178                         rdev->raid_disk = role;
1179                         break;
1180                 }
1181                 if (sb->devflags & WriteMostly1)
1182                         set_bit(WriteMostly, &rdev->flags);
1183         } else /* MULTIPATH are always insync */
1184                 set_bit(In_sync, &rdev->flags);
1185
1186         return 0;
1187 }
1188
1189 static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
1190 {
1191         struct mdp_superblock_1 *sb;
1192         struct list_head *tmp;
1193         mdk_rdev_t *rdev2;
1194         int max_dev, i;
1195         /* make rdev->sb match mddev and rdev data. */
1196
1197         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1198
1199         sb->feature_map = 0;
1200         sb->pad0 = 0;
1201         memset(sb->pad1, 0, sizeof(sb->pad1));
1202         memset(sb->pad2, 0, sizeof(sb->pad2));
1203         memset(sb->pad3, 0, sizeof(sb->pad3));
1204
1205         sb->utime = cpu_to_le64((__u64)mddev->utime);
1206         sb->events = cpu_to_le64(mddev->events);
1207         if (mddev->in_sync)
1208                 sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
1209         else
1210                 sb->resync_offset = cpu_to_le64(0);
1211
1212         sb->cnt_corrected_read = atomic_read(&rdev->corrected_errors);
1213
1214         sb->raid_disks = cpu_to_le32(mddev->raid_disks);
1215         sb->size = cpu_to_le64(mddev->size<<1);
1216
1217         if (mddev->bitmap && mddev->bitmap_file == NULL) {
1218                 sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_offset);
1219                 sb->feature_map = cpu_to_le32(MD_FEATURE_BITMAP_OFFSET);
1220         }
1221         if (mddev->reshape_position != MaxSector) {
1222                 sb->feature_map |= cpu_to_le32(MD_FEATURE_RESHAPE_ACTIVE);
1223                 sb->reshape_position = cpu_to_le64(mddev->reshape_position);
1224                 sb->new_layout = cpu_to_le32(mddev->new_layout);
1225                 sb->delta_disks = cpu_to_le32(mddev->delta_disks);
1226                 sb->new_level = cpu_to_le32(mddev->new_level);
1227                 sb->new_chunk = cpu_to_le32(mddev->new_chunk>>9);
1228         }
1229
1230         max_dev = 0;
1231         ITERATE_RDEV(mddev,rdev2,tmp)
1232                 if (rdev2->desc_nr+1 > max_dev)
1233                         max_dev = rdev2->desc_nr+1;
1234
1235         sb->max_dev = cpu_to_le32(max_dev);
1236         for (i=0; i<max_dev;i++)
1237                 sb->dev_roles[i] = cpu_to_le16(0xfffe);
1238
1239         ITERATE_RDEV(mddev,rdev2,tmp) {
1240                 i = rdev2->desc_nr;
1241                 if (test_bit(Faulty, &rdev2->flags))
1242                         sb->dev_roles[i] = cpu_to_le16(0xfffe);
1243                 else if (test_bit(In_sync, &rdev2->flags))
1244                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1245                 else
1246                         sb->dev_roles[i] = cpu_to_le16(0xffff);
1247         }
1248
1249         sb->recovery_offset = cpu_to_le64(0); /* not supported yet */
1250         sb->sb_csum = calc_sb_1_csum(sb);
1251 }
1252
1253
1254 static struct super_type super_types[] = {
1255         [0] = {
1256                 .name   = "0.90.0",
1257                 .owner  = THIS_MODULE,
1258                 .load_super     = super_90_load,
1259                 .validate_super = super_90_validate,
1260                 .sync_super     = super_90_sync,
1261         },
1262         [1] = {
1263                 .name   = "md-1",
1264                 .owner  = THIS_MODULE,
1265                 .load_super     = super_1_load,
1266                 .validate_super = super_1_validate,
1267                 .sync_super     = super_1_sync,
1268         },
1269 };
1270
1271 static mdk_rdev_t * match_dev_unit(mddev_t *mddev, mdk_rdev_t *dev)
1272 {
1273         struct list_head *tmp;
1274         mdk_rdev_t *rdev;
1275
1276         ITERATE_RDEV(mddev,rdev,tmp)
1277                 if (rdev->bdev->bd_contains == dev->bdev->bd_contains)
1278                         return rdev;
1279
1280         return NULL;
1281 }
1282
1283 static int match_mddev_units(mddev_t *mddev1, mddev_t *mddev2)
1284 {
1285         struct list_head *tmp;
1286         mdk_rdev_t *rdev;
1287
1288         ITERATE_RDEV(mddev1,rdev,tmp)
1289                 if (match_dev_unit(mddev2, rdev))
1290                         return 1;
1291
1292         return 0;
1293 }
1294
1295 static LIST_HEAD(pending_raid_disks);
1296
1297 static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
1298 {
1299         mdk_rdev_t *same_pdev;
1300         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1301         struct kobject *ko;
1302         char *s;
1303
1304         if (rdev->mddev) {
1305                 MD_BUG();
1306                 return -EINVAL;
1307         }
1308         /* make sure rdev->size exceeds mddev->size */
1309         if (rdev->size && (mddev->size == 0 || rdev->size < mddev->size)) {
1310                 if (mddev->pers)
1311                         /* Cannot change size, so fail */
1312                         return -ENOSPC;
1313                 else
1314                         mddev->size = rdev->size;
1315         }
1316         same_pdev = match_dev_unit(mddev, rdev);
1317         if (same_pdev)
1318                 printk(KERN_WARNING
1319                         "%s: WARNING: %s appears to be on the same physical"
1320                         " disk as %s. True\n     protection against single-disk"
1321                         " failure might be compromised.\n",
1322                         mdname(mddev), bdevname(rdev->bdev,b),
1323                         bdevname(same_pdev->bdev,b2));
1324
1325         /* Verify rdev->desc_nr is unique.
1326          * If it is -1, assign a free number, else
1327          * check number is not in use
1328          */
1329         if (rdev->desc_nr < 0) {
1330                 int choice = 0;
1331                 if (mddev->pers) choice = mddev->raid_disks;
1332                 while (find_rdev_nr(mddev, choice))
1333                         choice++;
1334                 rdev->desc_nr = choice;
1335         } else {
1336                 if (find_rdev_nr(mddev, rdev->desc_nr))
1337                         return -EBUSY;
1338         }
1339         bdevname(rdev->bdev,b);
1340         if (kobject_set_name(&rdev->kobj, "dev-%s", b) < 0)
1341                 return -ENOMEM;
1342         while ( (s=strchr(rdev->kobj.k_name, '/')) != NULL)
1343                 *s = '!';
1344
1345         list_add(&rdev->same_set, &mddev->disks);
1346         rdev->mddev = mddev;
1347         printk(KERN_INFO "md: bind<%s>\n", b);
1348
1349         rdev->kobj.parent = &mddev->kobj;
1350         kobject_add(&rdev->kobj);
1351
1352         if (rdev->bdev->bd_part)
1353                 ko = &rdev->bdev->bd_part->kobj;
1354         else
1355                 ko = &rdev->bdev->bd_disk->kobj;
1356         sysfs_create_link(&rdev->kobj, ko, "block");
1357         bd_claim_by_disk(rdev->bdev, rdev, mddev->gendisk);
1358         return 0;
1359 }
1360
1361 static void unbind_rdev_from_array(mdk_rdev_t * rdev)
1362 {
1363         char b[BDEVNAME_SIZE];
1364         if (!rdev->mddev) {
1365                 MD_BUG();
1366                 return;
1367         }
1368         bd_release_from_disk(rdev->bdev, rdev->mddev->gendisk);
1369         list_del_init(&rdev->same_set);
1370         printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
1371         rdev->mddev = NULL;
1372         sysfs_remove_link(&rdev->kobj, "block");
1373         kobject_del(&rdev->kobj);
1374 }
1375
1376 /*
1377  * prevent the device from being mounted, repartitioned or
1378  * otherwise reused by a RAID array (or any other kernel
1379  * subsystem), by bd_claiming the device.
1380  */
1381 static int lock_rdev(mdk_rdev_t *rdev, dev_t dev)
1382 {
1383         int err = 0;
1384         struct block_device *bdev;
1385         char b[BDEVNAME_SIZE];
1386
1387         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
1388         if (IS_ERR(bdev)) {
1389                 printk(KERN_ERR "md: could not open %s.\n",
1390                         __bdevname(dev, b));
1391                 return PTR_ERR(bdev);
1392         }
1393         err = bd_claim(bdev, rdev);
1394         if (err) {
1395                 printk(KERN_ERR "md: could not bd_claim %s.\n",
1396                         bdevname(bdev, b));
1397                 blkdev_put(bdev);
1398                 return err;
1399         }
1400         rdev->bdev = bdev;
1401         return err;
1402 }
1403
1404 static void unlock_rdev(mdk_rdev_t *rdev)
1405 {
1406         struct block_device *bdev = rdev->bdev;
1407         rdev->bdev = NULL;
1408         if (!bdev)
1409                 MD_BUG();
1410         bd_release(bdev);
1411         blkdev_put(bdev);
1412 }
1413
1414 void md_autodetect_dev(dev_t dev);
1415
1416 static void export_rdev(mdk_rdev_t * rdev)
1417 {
1418         char b[BDEVNAME_SIZE];
1419         printk(KERN_INFO "md: export_rdev(%s)\n",
1420                 bdevname(rdev->bdev,b));
1421         if (rdev->mddev)
1422                 MD_BUG();
1423         free_disk_sb(rdev);
1424         list_del_init(&rdev->same_set);
1425 #ifndef MODULE
1426         md_autodetect_dev(rdev->bdev->bd_dev);
1427 #endif
1428         unlock_rdev(rdev);
1429         kobject_put(&rdev->kobj);
1430 }
1431
1432 static void kick_rdev_from_array(mdk_rdev_t * rdev)
1433 {
1434         unbind_rdev_from_array(rdev);
1435         export_rdev(rdev);
1436 }
1437
1438 static void export_array(mddev_t *mddev)
1439 {
1440         struct list_head *tmp;
1441         mdk_rdev_t *rdev;
1442
1443         ITERATE_RDEV(mddev,rdev,tmp) {
1444                 if (!rdev->mddev) {
1445                         MD_BUG();
1446                         continue;
1447                 }
1448                 kick_rdev_from_array(rdev);
1449         }
1450         if (!list_empty(&mddev->disks))
1451                 MD_BUG();
1452         mddev->raid_disks = 0;
1453         mddev->major_version = 0;
1454 }
1455
1456 static void print_desc(mdp_disk_t *desc)
1457 {
1458         printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
1459                 desc->major,desc->minor,desc->raid_disk,desc->state);
1460 }
1461
1462 static void print_sb(mdp_super_t *sb)
1463 {
1464         int i;
1465
1466         printk(KERN_INFO
1467                 "md:  SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
1468                 sb->major_version, sb->minor_version, sb->patch_version,
1469                 sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
1470                 sb->ctime);
1471         printk(KERN_INFO "md:     L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
1472                 sb->level, sb->size, sb->nr_disks, sb->raid_disks,
1473                 sb->md_minor, sb->layout, sb->chunk_size);
1474         printk(KERN_INFO "md:     UT:%08x ST:%d AD:%d WD:%d"
1475                 " FD:%d SD:%d CSUM:%08x E:%08lx\n",
1476                 sb->utime, sb->state, sb->active_disks, sb->working_disks,
1477                 sb->failed_disks, sb->spare_disks,
1478                 sb->sb_csum, (unsigned long)sb->events_lo);
1479
1480         printk(KERN_INFO);
1481         for (i = 0; i < MD_SB_DISKS; i++) {
1482                 mdp_disk_t *desc;
1483
1484                 desc = sb->disks + i;
1485                 if (desc->number || desc->major || desc->minor ||
1486                     desc->raid_disk || (desc->state && (desc->state != 4))) {
1487                         printk("     D %2d: ", i);
1488                         print_desc(desc);
1489                 }
1490         }
1491         printk(KERN_INFO "md:     THIS: ");
1492         print_desc(&sb->this_disk);
1493
1494 }
1495
1496 static void print_rdev(mdk_rdev_t *rdev)
1497 {
1498         char b[BDEVNAME_SIZE];
1499         printk(KERN_INFO "md: rdev %s, SZ:%08llu F:%d S:%d DN:%u\n",
1500                 bdevname(rdev->bdev,b), (unsigned long long)rdev->size,
1501                 test_bit(Faulty, &rdev->flags), test_bit(In_sync, &rdev->flags),
1502                 rdev->desc_nr);
1503         if (rdev->sb_loaded) {
1504                 printk(KERN_INFO "md: rdev superblock:\n");
1505                 print_sb((mdp_super_t*)page_address(rdev->sb_page));
1506         } else
1507                 printk(KERN_INFO "md: no rdev superblock!\n");
1508 }
1509
1510 void md_print_devices(void)
1511 {
1512         struct list_head *tmp, *tmp2;
1513         mdk_rdev_t *rdev;
1514         mddev_t *mddev;
1515         char b[BDEVNAME_SIZE];
1516
1517         printk("\n");
1518         printk("md:     **********************************\n");
1519         printk("md:     * <COMPLETE RAID STATE PRINTOUT> *\n");
1520         printk("md:     **********************************\n");
1521         ITERATE_MDDEV(mddev,tmp) {
1522
1523                 if (mddev->bitmap)
1524                         bitmap_print_sb(mddev->bitmap);
1525                 else
1526                         printk("%s: ", mdname(mddev));
1527                 ITERATE_RDEV(mddev,rdev,tmp2)
1528                         printk("<%s>", bdevname(rdev->bdev,b));
1529                 printk("\n");
1530
1531                 ITERATE_RDEV(mddev,rdev,tmp2)
1532                         print_rdev(rdev);
1533         }
1534         printk("md:     **********************************\n");
1535         printk("\n");
1536 }
1537
1538
1539 static void sync_sbs(mddev_t * mddev)
1540 {
1541         mdk_rdev_t *rdev;
1542         struct list_head *tmp;
1543
1544         ITERATE_RDEV(mddev,rdev,tmp) {
1545                 super_types[mddev->major_version].
1546                         sync_super(mddev, rdev);
1547                 rdev->sb_loaded = 1;
1548         }
1549 }
1550
1551 void md_update_sb(mddev_t * mddev)
1552 {
1553         int err;
1554         struct list_head *tmp;
1555         mdk_rdev_t *rdev;
1556         int sync_req;
1557
1558 repeat:
1559         spin_lock_irq(&mddev->write_lock);
1560         sync_req = mddev->in_sync;
1561         mddev->utime = get_seconds();
1562         mddev->events ++;
1563
1564         if (!mddev->events) {
1565                 /*
1566                  * oops, this 64-bit counter should never wrap.
1567                  * Either we are in around ~1 trillion A.C., assuming
1568                  * 1 reboot per second, or we have a bug:
1569                  */
1570                 MD_BUG();
1571                 mddev->events --;
1572         }
1573         mddev->sb_dirty = 2;
1574         sync_sbs(mddev);
1575
1576         /*
1577          * do not write anything to disk if using
1578          * nonpersistent superblocks
1579          */
1580         if (!mddev->persistent) {
1581                 mddev->sb_dirty = 0;
1582                 spin_unlock_irq(&mddev->write_lock);
1583                 wake_up(&mddev->sb_wait);
1584                 return;
1585         }
1586         spin_unlock_irq(&mddev->write_lock);
1587
1588         dprintk(KERN_INFO
1589                 "md: updating %s RAID superblock on device (in sync %d)\n",
1590                 mdname(mddev),mddev->in_sync);
1591
1592         err = bitmap_update_sb(mddev->bitmap);
1593         ITERATE_RDEV(mddev,rdev,tmp) {
1594                 char b[BDEVNAME_SIZE];
1595                 dprintk(KERN_INFO "md: ");
1596                 if (test_bit(Faulty, &rdev->flags))
1597                         dprintk("(skipping faulty ");
1598
1599                 dprintk("%s ", bdevname(rdev->bdev,b));
1600                 if (!test_bit(Faulty, &rdev->flags)) {
1601                         md_super_write(mddev,rdev,
1602                                        rdev->sb_offset<<1, rdev->sb_size,
1603                                        rdev->sb_page);
1604                         dprintk(KERN_INFO "(write) %s's sb offset: %llu\n",
1605                                 bdevname(rdev->bdev,b),
1606                                 (unsigned long long)rdev->sb_offset);
1607
1608                 } else
1609                         dprintk(")\n");
1610                 if (mddev->level == LEVEL_MULTIPATH)
1611                         /* only need to write one superblock... */
1612                         break;
1613         }
1614         md_super_wait(mddev);
1615         /* if there was a failure, sb_dirty was set to 1, and we re-write super */
1616
1617         spin_lock_irq(&mddev->write_lock);
1618         if (mddev->in_sync != sync_req|| mddev->sb_dirty == 1) {
1619                 /* have to write it out again */
1620                 spin_unlock_irq(&mddev->write_lock);
1621                 goto repeat;
1622         }
1623         mddev->sb_dirty = 0;
1624         spin_unlock_irq(&mddev->write_lock);
1625         wake_up(&mddev->sb_wait);
1626
1627 }
1628 EXPORT_SYMBOL_GPL(md_update_sb);
1629
1630 /* words written to sysfs files may, or my not, be \n terminated.
1631  * We want to accept with case. For this we use cmd_match.
1632  */
1633 static int cmd_match(const char *cmd, const char *str)
1634 {
1635         /* See if cmd, written into a sysfs file, matches
1636          * str.  They must either be the same, or cmd can
1637          * have a trailing newline
1638          */
1639         while (*cmd && *str && *cmd == *str) {
1640                 cmd++;
1641                 str++;
1642         }
1643         if (*cmd == '\n')
1644                 cmd++;
1645         if (*str || *cmd)
1646                 return 0;
1647         return 1;
1648 }
1649
1650 struct rdev_sysfs_entry {
1651         struct attribute attr;
1652         ssize_t (*show)(mdk_rdev_t *, char *);
1653         ssize_t (*store)(mdk_rdev_t *, const char *, size_t);
1654 };
1655
1656 static ssize_t
1657 state_show(mdk_rdev_t *rdev, char *page)
1658 {
1659         char *sep = "";
1660         int len=0;
1661
1662         if (test_bit(Faulty, &rdev->flags)) {
1663                 len+= sprintf(page+len, "%sfaulty",sep);
1664                 sep = ",";
1665         }
1666         if (test_bit(In_sync, &rdev->flags)) {
1667                 len += sprintf(page+len, "%sin_sync",sep);
1668                 sep = ",";
1669         }
1670         if (!test_bit(Faulty, &rdev->flags) &&
1671             !test_bit(In_sync, &rdev->flags)) {
1672                 len += sprintf(page+len, "%sspare", sep);
1673                 sep = ",";
1674         }
1675         return len+sprintf(page+len, "\n");
1676 }
1677
1678 static struct rdev_sysfs_entry
1679 rdev_state = __ATTR_RO(state);
1680
1681 static ssize_t
1682 super_show(mdk_rdev_t *rdev, char *page)
1683 {
1684         if (rdev->sb_loaded && rdev->sb_size) {
1685                 memcpy(page, page_address(rdev->sb_page), rdev->sb_size);
1686                 return rdev->sb_size;
1687         } else
1688                 return 0;
1689 }
1690 static struct rdev_sysfs_entry rdev_super = __ATTR_RO(super);
1691
1692 static ssize_t
1693 errors_show(mdk_rdev_t *rdev, char *page)
1694 {
1695         return sprintf(page, "%d\n", atomic_read(&rdev->corrected_errors));
1696 }
1697
1698 static ssize_t
1699 errors_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1700 {
1701         char *e;
1702         unsigned long n = simple_strtoul(buf, &e, 10);
1703         if (*buf && (*e == 0 || *e == '\n')) {
1704                 atomic_set(&rdev->corrected_errors, n);
1705                 return len;
1706         }
1707         return -EINVAL;
1708 }
1709 static struct rdev_sysfs_entry rdev_errors =
1710 __ATTR(errors, 0644, errors_show, errors_store);
1711
1712 static ssize_t
1713 slot_show(mdk_rdev_t *rdev, char *page)
1714 {
1715         if (rdev->raid_disk < 0)
1716                 return sprintf(page, "none\n");
1717         else
1718                 return sprintf(page, "%d\n", rdev->raid_disk);
1719 }
1720
1721 static ssize_t
1722 slot_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1723 {
1724         char *e;
1725         int slot = simple_strtoul(buf, &e, 10);
1726         if (strncmp(buf, "none", 4)==0)
1727                 slot = -1;
1728         else if (e==buf || (*e && *e!= '\n'))
1729                 return -EINVAL;
1730         if (rdev->mddev->pers)
1731                 /* Cannot set slot in active array (yet) */
1732                 return -EBUSY;
1733         if (slot >= rdev->mddev->raid_disks)
1734                 return -ENOSPC;
1735         rdev->raid_disk = slot;
1736         /* assume it is working */
1737         rdev->flags = 0;
1738         set_bit(In_sync, &rdev->flags);
1739         return len;
1740 }
1741
1742
1743 static struct rdev_sysfs_entry rdev_slot =
1744 __ATTR(slot, 0644, slot_show, slot_store);
1745
1746 static ssize_t
1747 offset_show(mdk_rdev_t *rdev, char *page)
1748 {
1749         return sprintf(page, "%llu\n", (unsigned long long)rdev->data_offset);
1750 }
1751
1752 static ssize_t
1753 offset_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1754 {
1755         char *e;
1756         unsigned long long offset = simple_strtoull(buf, &e, 10);
1757         if (e==buf || (*e && *e != '\n'))
1758                 return -EINVAL;
1759         if (rdev->mddev->pers)
1760                 return -EBUSY;
1761         rdev->data_offset = offset;
1762         return len;
1763 }
1764
1765 static struct rdev_sysfs_entry rdev_offset =
1766 __ATTR(offset, 0644, offset_show, offset_store);
1767
1768 static ssize_t
1769 rdev_size_show(mdk_rdev_t *rdev, char *page)
1770 {
1771         return sprintf(page, "%llu\n", (unsigned long long)rdev->size);
1772 }
1773
1774 static ssize_t
1775 rdev_size_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1776 {
1777         char *e;
1778         unsigned long long size = simple_strtoull(buf, &e, 10);
1779         if (e==buf || (*e && *e != '\n'))
1780                 return -EINVAL;
1781         if (rdev->mddev->pers)
1782                 return -EBUSY;
1783         rdev->size = size;
1784         if (size < rdev->mddev->size || rdev->mddev->size == 0)
1785                 rdev->mddev->size = size;
1786         return len;
1787 }
1788
1789 static struct rdev_sysfs_entry rdev_size =
1790 __ATTR(size, 0644, rdev_size_show, rdev_size_store);
1791
1792 static struct attribute *rdev_default_attrs[] = {
1793         &rdev_state.attr,
1794         &rdev_super.attr,
1795         &rdev_errors.attr,
1796         &rdev_slot.attr,
1797         &rdev_offset.attr,
1798         &rdev_size.attr,
1799         NULL,
1800 };
1801 static ssize_t
1802 rdev_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
1803 {
1804         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
1805         mdk_rdev_t *rdev = container_of(kobj, mdk_rdev_t, kobj);
1806
1807         if (!entry->show)
1808                 return -EIO;
1809         return entry->show(rdev, page);
1810 }
1811
1812 static ssize_t
1813 rdev_attr_store(struct kobject *kobj, struct attribute *attr,
1814               const char *page, size_t length)
1815 {
1816         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
1817         mdk_rdev_t *rdev = container_of(kobj, mdk_rdev_t, kobj);
1818
1819         if (!entry->store)
1820                 return -EIO;
1821         return entry->store(rdev, page, length);
1822 }
1823
1824 static void rdev_free(struct kobject *ko)
1825 {
1826         mdk_rdev_t *rdev = container_of(ko, mdk_rdev_t, kobj);
1827         kfree(rdev);
1828 }
1829 static struct sysfs_ops rdev_sysfs_ops = {
1830         .show           = rdev_attr_show,
1831         .store          = rdev_attr_store,
1832 };
1833 static struct kobj_type rdev_ktype = {
1834         .release        = rdev_free,
1835         .sysfs_ops      = &rdev_sysfs_ops,
1836         .default_attrs  = rdev_default_attrs,
1837 };
1838
1839 /*
1840  * Import a device. If 'super_format' >= 0, then sanity check the superblock
1841  *
1842  * mark the device faulty if:
1843  *
1844  *   - the device is nonexistent (zero size)
1845  *   - the device has no valid superblock
1846  *
1847  * a faulty rdev _never_ has rdev->sb set.
1848  */
1849 static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_minor)
1850 {
1851         char b[BDEVNAME_SIZE];
1852         int err;
1853         mdk_rdev_t *rdev;
1854         sector_t size;
1855
1856         rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
1857         if (!rdev) {
1858                 printk(KERN_ERR "md: could not alloc mem for new device!\n");
1859                 return ERR_PTR(-ENOMEM);
1860         }
1861
1862         if ((err = alloc_disk_sb(rdev)))
1863                 goto abort_free;
1864
1865         err = lock_rdev(rdev, newdev);
1866         if (err)
1867                 goto abort_free;
1868
1869         rdev->kobj.parent = NULL;
1870         rdev->kobj.ktype = &rdev_ktype;
1871         kobject_init(&rdev->kobj);
1872
1873         rdev->desc_nr = -1;
1874         rdev->flags = 0;
1875         rdev->data_offset = 0;
1876         atomic_set(&rdev->nr_pending, 0);
1877         atomic_set(&rdev->read_errors, 0);
1878         atomic_set(&rdev->corrected_errors, 0);
1879
1880         size = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
1881         if (!size) {
1882                 printk(KERN_WARNING
1883                         "md: %s has zero or unknown size, marking faulty!\n",
1884                         bdevname(rdev->bdev,b));
1885                 err = -EINVAL;
1886                 goto abort_free;
1887         }
1888
1889         if (super_format >= 0) {
1890                 err = super_types[super_format].
1891                         load_super(rdev, NULL, super_minor);
1892                 if (err == -EINVAL) {
1893                         printk(KERN_WARNING
1894                                 "md: %s has invalid sb, not importing!\n",
1895                                 bdevname(rdev->bdev,b));
1896                         goto abort_free;
1897                 }
1898                 if (err < 0) {
1899                         printk(KERN_WARNING
1900                                 "md: could not read %s's sb, not importing!\n",
1901                                 bdevname(rdev->bdev,b));
1902                         goto abort_free;
1903                 }
1904         }
1905         INIT_LIST_HEAD(&rdev->same_set);
1906
1907         return rdev;
1908
1909 abort_free:
1910         if (rdev->sb_page) {
1911                 if (rdev->bdev)
1912                         unlock_rdev(rdev);
1913                 free_disk_sb(rdev);
1914         }
1915         kfree(rdev);
1916         return ERR_PTR(err);
1917 }
1918
1919 /*
1920  * Check a full RAID array for plausibility
1921  */
1922
1923
1924 static void analyze_sbs(mddev_t * mddev)
1925 {
1926         int i;
1927         struct list_head *tmp;
1928         mdk_rdev_t *rdev, *freshest;
1929         char b[BDEVNAME_SIZE];
1930
1931         freshest = NULL;
1932         ITERATE_RDEV(mddev,rdev,tmp)
1933                 switch (super_types[mddev->major_version].
1934                         load_super(rdev, freshest, mddev->minor_version)) {
1935                 case 1:
1936                         freshest = rdev;
1937                         break;
1938                 case 0:
1939                         break;
1940                 default:
1941                         printk( KERN_ERR \
1942                                 "md: fatal superblock inconsistency in %s"
1943                                 " -- removing from array\n",
1944                                 bdevname(rdev->bdev,b));
1945                         kick_rdev_from_array(rdev);
1946                 }
1947
1948
1949         super_types[mddev->major_version].
1950                 validate_super(mddev, freshest);
1951
1952         i = 0;
1953         ITERATE_RDEV(mddev,rdev,tmp) {
1954                 if (rdev != freshest)
1955                         if (super_types[mddev->major_version].
1956                             validate_super(mddev, rdev)) {
1957                                 printk(KERN_WARNING "md: kicking non-fresh %s"
1958                                         " from array!\n",
1959                                         bdevname(rdev->bdev,b));
1960                                 kick_rdev_from_array(rdev);
1961                                 continue;
1962                         }
1963                 if (mddev->level == LEVEL_MULTIPATH) {
1964                         rdev->desc_nr = i++;
1965                         rdev->raid_disk = rdev->desc_nr;
1966                         set_bit(In_sync, &rdev->flags);
1967                 }
1968         }
1969
1970
1971
1972         if (mddev->recovery_cp != MaxSector &&
1973             mddev->level >= 1)
1974                 printk(KERN_ERR "md: %s: raid array is not clean"
1975                        " -- starting background reconstruction\n",
1976                        mdname(mddev));
1977
1978 }
1979
1980 static ssize_t
1981 level_show(mddev_t *mddev, char *page)
1982 {
1983         struct mdk_personality *p = mddev->pers;
1984         if (p)
1985                 return sprintf(page, "%s\n", p->name);
1986         else if (mddev->clevel[0])
1987                 return sprintf(page, "%s\n", mddev->clevel);
1988         else if (mddev->level != LEVEL_NONE)
1989                 return sprintf(page, "%d\n", mddev->level);
1990         else
1991                 return 0;
1992 }
1993
1994 static ssize_t
1995 level_store(mddev_t *mddev, const char *buf, size_t len)
1996 {
1997         int rv = len;
1998         if (mddev->pers)
1999                 return -EBUSY;
2000         if (len == 0)
2001                 return 0;
2002         if (len >= sizeof(mddev->clevel))
2003                 return -ENOSPC;
2004         strncpy(mddev->clevel, buf, len);
2005         if (mddev->clevel[len-1] == '\n')
2006                 len--;
2007         mddev->clevel[len] = 0;
2008         mddev->level = LEVEL_NONE;
2009         return rv;
2010 }
2011
2012 static struct md_sysfs_entry md_level =
2013 __ATTR(level, 0644, level_show, level_store);
2014
2015 static ssize_t
2016 raid_disks_show(mddev_t *mddev, char *page)
2017 {
2018         if (mddev->raid_disks == 0)
2019                 return 0;
2020         return sprintf(page, "%d\n", mddev->raid_disks);
2021 }
2022
2023 static int update_raid_disks(mddev_t *mddev, int raid_disks);
2024
2025 static ssize_t
2026 raid_disks_store(mddev_t *mddev, const char *buf, size_t len)
2027 {
2028         /* can only set raid_disks if array is not yet active */
2029         char *e;
2030         int rv = 0;
2031         unsigned long n = simple_strtoul(buf, &e, 10);
2032
2033         if (!*buf || (*e && *e != '\n'))
2034                 return -EINVAL;
2035
2036         if (mddev->pers)
2037                 rv = update_raid_disks(mddev, n);
2038         else
2039                 mddev->raid_disks = n;
2040         return rv ? rv : len;
2041 }
2042 static struct md_sysfs_entry md_raid_disks =
2043 __ATTR(raid_disks, 0644, raid_disks_show, raid_disks_store);
2044
2045 static ssize_t
2046 chunk_size_show(mddev_t *mddev, char *page)
2047 {
2048         return sprintf(page, "%d\n", mddev->chunk_size);
2049 }
2050
2051 static ssize_t
2052 chunk_size_store(mddev_t *mddev, const char *buf, size_t len)
2053 {
2054         /* can only set chunk_size if array is not yet active */
2055         char *e;
2056         unsigned long n = simple_strtoul(buf, &e, 10);
2057
2058         if (mddev->pers)
2059                 return -EBUSY;
2060         if (!*buf || (*e && *e != '\n'))
2061                 return -EINVAL;
2062
2063         mddev->chunk_size = n;
2064         return len;
2065 }
2066 static struct md_sysfs_entry md_chunk_size =
2067 __ATTR(chunk_size, 0644, chunk_size_show, chunk_size_store);
2068
2069 static ssize_t
2070 null_show(mddev_t *mddev, char *page)
2071 {
2072         return -EINVAL;
2073 }
2074
2075 static ssize_t
2076 new_dev_store(mddev_t *mddev, const char *buf, size_t len)
2077 {
2078         /* buf must be %d:%d\n? giving major and minor numbers */
2079         /* The new device is added to the array.
2080          * If the array has a persistent superblock, we read the
2081          * superblock to initialise info and check validity.
2082          * Otherwise, only checking done is that in bind_rdev_to_array,
2083          * which mainly checks size.
2084          */
2085         char *e;
2086         int major = simple_strtoul(buf, &e, 10);
2087         int minor;
2088         dev_t dev;
2089         mdk_rdev_t *rdev;
2090         int err;
2091
2092         if (!*buf || *e != ':' || !e[1] || e[1] == '\n')
2093                 return -EINVAL;
2094         minor = simple_strtoul(e+1, &e, 10);
2095         if (*e && *e != '\n')
2096                 return -EINVAL;
2097         dev = MKDEV(major, minor);
2098         if (major != MAJOR(dev) ||
2099             minor != MINOR(dev))
2100                 return -EOVERFLOW;
2101
2102
2103         if (mddev->persistent) {
2104                 rdev = md_import_device(dev, mddev->major_version,
2105                                         mddev->minor_version);
2106                 if (!IS_ERR(rdev) && !list_empty(&mddev->disks)) {
2107                         mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
2108                                                        mdk_rdev_t, same_set);
2109                         err = super_types[mddev->major_version]
2110                                 .load_super(rdev, rdev0, mddev->minor_version);
2111                         if (err < 0)
2112                                 goto out;
2113                 }
2114         } else
2115                 rdev = md_import_device(dev, -1, -1);
2116
2117         if (IS_ERR(rdev))
2118                 return PTR_ERR(rdev);
2119         err = bind_rdev_to_array(rdev, mddev);
2120  out:
2121         if (err)
2122                 export_rdev(rdev);
2123         return err ? err : len;
2124 }
2125
2126 static struct md_sysfs_entry md_new_device =
2127 __ATTR(new_dev, 0200, null_show, new_dev_store);
2128
2129 static ssize_t
2130 size_show(mddev_t *mddev, char *page)
2131 {
2132         return sprintf(page, "%llu\n", (unsigned long long)mddev->size);
2133 }
2134
2135 static int update_size(mddev_t *mddev, unsigned long size);
2136
2137 static ssize_t
2138 size_store(mddev_t *mddev, const char *buf, size_t len)
2139 {
2140         /* If array is inactive, we can reduce the component size, but
2141          * not increase it (except from 0).
2142          * If array is active, we can try an on-line resize
2143          */
2144         char *e;
2145         int err = 0;
2146         unsigned long long size = simple_strtoull(buf, &e, 10);
2147         if (!*buf || *buf == '\n' ||
2148             (*e && *e != '\n'))
2149                 return -EINVAL;
2150
2151         if (mddev->pers) {
2152                 err = update_size(mddev, size);
2153                 md_update_sb(mddev);
2154         } else {
2155                 if (mddev->size == 0 ||
2156                     mddev->size > size)
2157                         mddev->size = size;
2158                 else
2159                         err = -ENOSPC;
2160         }
2161         return err ? err : len;
2162 }
2163
2164 static struct md_sysfs_entry md_size =
2165 __ATTR(component_size, 0644, size_show, size_store);
2166
2167
2168 /* Metdata version.
2169  * This is either 'none' for arrays with externally managed metadata,
2170  * or N.M for internally known formats
2171  */
2172 static ssize_t
2173 metadata_show(mddev_t *mddev, char *page)
2174 {
2175         if (mddev->persistent)
2176                 return sprintf(page, "%d.%d\n",
2177                                mddev->major_version, mddev->minor_version);
2178         else
2179                 return sprintf(page, "none\n");
2180 }
2181
2182 static ssize_t
2183 metadata_store(mddev_t *mddev, const char *buf, size_t len)
2184 {
2185         int major, minor;
2186         char *e;
2187         if (!list_empty(&mddev->disks))
2188                 return -EBUSY;
2189
2190         if (cmd_match(buf, "none")) {
2191                 mddev->persistent = 0;
2192                 mddev->major_version = 0;
2193                 mddev->minor_version = 90;
2194                 return len;
2195         }
2196         major = simple_strtoul(buf, &e, 10);
2197         if (e==buf || *e != '.')
2198                 return -EINVAL;
2199         buf = e+1;
2200         minor = simple_strtoul(buf, &e, 10);
2201         if (e==buf || *e != '\n')
2202                 return -EINVAL;
2203         if (major >= sizeof(super_types)/sizeof(super_types[0]) ||
2204             super_types[major].name == NULL)
2205                 return -ENOENT;
2206         mddev->major_version = major;
2207         mddev->minor_version = minor;
2208         mddev->persistent = 1;
2209         return len;
2210 }
2211
2212 static struct md_sysfs_entry md_metadata =
2213 __ATTR(metadata_version, 0644, metadata_show, metadata_store);
2214
2215 static ssize_t
2216 action_show(mddev_t *mddev, char *page)
2217 {
2218         char *type = "idle";
2219         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
2220             test_bit(MD_RECOVERY_NEEDED, &mddev->recovery)) {
2221                 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
2222                         type = "reshape";
2223                 else if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
2224                         if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2225                                 type = "resync";
2226                         else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
2227                                 type = "check";
2228                         else
2229                                 type = "repair";
2230                 } else
2231                         type = "recover";
2232         }
2233         return sprintf(page, "%s\n", type);
2234 }
2235
2236 static ssize_t
2237 action_store(mddev_t *mddev, const char *page, size_t len)
2238 {
2239         if (!mddev->pers || !mddev->pers->sync_request)
2240                 return -EINVAL;
2241
2242         if (cmd_match(page, "idle")) {
2243                 if (mddev->sync_thread) {
2244                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2245                         md_unregister_thread(mddev->sync_thread);
2246                         mddev->sync_thread = NULL;
2247                         mddev->recovery = 0;
2248                 }
2249         } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
2250                    test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
2251                 return -EBUSY;
2252         else if (cmd_match(page, "resync") || cmd_match(page, "recover"))
2253                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2254         else if (cmd_match(page, "reshape")) {
2255                 int err;
2256                 if (mddev->pers->start_reshape == NULL)
2257                         return -EINVAL;
2258                 err = mddev->pers->start_reshape(mddev);
2259                 if (err)
2260                         return err;
2261         } else {
2262                 if (cmd_match(page, "check"))
2263                         set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
2264                 else if (!cmd_match(page, "repair"))
2265                         return -EINVAL;
2266                 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
2267                 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
2268         }
2269         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2270         md_wakeup_thread(mddev->thread);
2271         return len;
2272 }
2273
2274 static ssize_t
2275 mismatch_cnt_show(mddev_t *mddev, char *page)
2276 {
2277         return sprintf(page, "%llu\n",
2278                        (unsigned long long) mddev->resync_mismatches);
2279 }
2280
2281 static struct md_sysfs_entry
2282 md_scan_mode = __ATTR(sync_action, S_IRUGO|S_IWUSR, action_show, action_store);
2283
2284
2285 static struct md_sysfs_entry
2286 md_mismatches = __ATTR_RO(mismatch_cnt);
2287
2288 static ssize_t
2289 sync_min_show(mddev_t *mddev, char *page)
2290 {
2291         return sprintf(page, "%d (%s)\n", speed_min(mddev),
2292                        mddev->sync_speed_min ? "local": "system");
2293 }
2294
2295 static ssize_t
2296 sync_min_store(mddev_t *mddev, const char *buf, size_t len)
2297 {
2298         int min;
2299         char *e;
2300         if (strncmp(buf, "system", 6)==0) {
2301                 mddev->sync_speed_min = 0;
2302                 return len;
2303         }
2304         min = simple_strtoul(buf, &e, 10);
2305         if (buf == e || (*e && *e != '\n') || min <= 0)
2306                 return -EINVAL;
2307         mddev->sync_speed_min = min;
2308         return len;
2309 }
2310
2311 static struct md_sysfs_entry md_sync_min =
2312 __ATTR(sync_speed_min, S_IRUGO|S_IWUSR, sync_min_show, sync_min_store);
2313
2314 static ssize_t
2315 sync_max_show(mddev_t *mddev, char *page)
2316 {
2317         return sprintf(page, "%d (%s)\n", speed_max(mddev),
2318                        mddev->sync_speed_max ? "local": "system");
2319 }
2320
2321 static ssize_t
2322 sync_max_store(mddev_t *mddev, const char *buf, size_t len)
2323 {
2324         int max;
2325         char *e;
2326         if (strncmp(buf, "system", 6)==0) {
2327                 mddev->sync_speed_max = 0;
2328                 return len;
2329         }
2330         max = simple_strtoul(buf, &e, 10);
2331         if (buf == e || (*e && *e != '\n') || max <= 0)
2332                 return -EINVAL;
2333         mddev->sync_speed_max = max;
2334         return len;
2335 }
2336
2337 static struct md_sysfs_entry md_sync_max =
2338 __ATTR(sync_speed_max, S_IRUGO|S_IWUSR, sync_max_show, sync_max_store);
2339
2340
2341 static ssize_t
2342 sync_speed_show(mddev_t *mddev, char *page)
2343 {
2344         unsigned long resync, dt, db;
2345         resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active));
2346         dt = ((jiffies - mddev->resync_mark) / HZ);
2347         if (!dt) dt++;
2348         db = resync - (mddev->resync_mark_cnt);
2349         return sprintf(page, "%ld\n", db/dt/2); /* K/sec */
2350 }
2351
2352 static struct md_sysfs_entry
2353 md_sync_speed = __ATTR_RO(sync_speed);
2354
2355 static ssize_t
2356 sync_completed_show(mddev_t *mddev, char *page)
2357 {
2358         unsigned long max_blocks, resync;
2359
2360         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
2361                 max_blocks = mddev->resync_max_sectors;
2362         else
2363                 max_blocks = mddev->size << 1;
2364
2365         resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active));
2366         return sprintf(page, "%lu / %lu\n", resync, max_blocks);
2367 }
2368
2369 static struct md_sysfs_entry
2370 md_sync_completed = __ATTR_RO(sync_completed);
2371
2372 static ssize_t
2373 suspend_lo_show(mddev_t *mddev, char *page)
2374 {
2375         return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_lo);
2376 }
2377
2378 static ssize_t
2379 suspend_lo_store(mddev_t *mddev, const char *buf, size_t len)
2380 {
2381         char *e;
2382         unsigned long long new = simple_strtoull(buf, &e, 10);
2383
2384         if (mddev->pers->quiesce == NULL)
2385                 return -EINVAL;
2386         if (buf == e || (*e && *e != '\n'))
2387                 return -EINVAL;
2388         if (new >= mddev->suspend_hi ||
2389             (new > mddev->suspend_lo && new < mddev->suspend_hi)) {
2390                 mddev->suspend_lo = new;
2391                 mddev->pers->quiesce(mddev, 2);
2392                 return len;
2393         } else
2394                 return -EINVAL;
2395 }
2396 static struct md_sysfs_entry md_suspend_lo =
2397 __ATTR(suspend_lo, S_IRUGO|S_IWUSR, suspend_lo_show, suspend_lo_store);
2398
2399
2400 static ssize_t
2401 suspend_hi_show(mddev_t *mddev, char *page)
2402 {
2403         return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_hi);
2404 }
2405
2406 static ssize_t
2407 suspend_hi_store(mddev_t *mddev, const char *buf, size_t len)
2408 {
2409         char *e;
2410         unsigned long long new = simple_strtoull(buf, &e, 10);
2411
2412         if (mddev->pers->quiesce == NULL)
2413                 return -EINVAL;
2414         if (buf == e || (*e && *e != '\n'))
2415                 return -EINVAL;
2416         if ((new <= mddev->suspend_lo && mddev->suspend_lo >= mddev->suspend_hi) ||
2417             (new > mddev->suspend_lo && new > mddev->suspend_hi)) {
2418                 mddev->suspend_hi = new;
2419                 mddev->pers->quiesce(mddev, 1);
2420                 mddev->pers->quiesce(mddev, 0);
2421                 return len;
2422         } else
2423                 return -EINVAL;
2424 }
2425 static struct md_sysfs_entry md_suspend_hi =
2426 __ATTR(suspend_hi, S_IRUGO|S_IWUSR, suspend_hi_show, suspend_hi_store);
2427
2428
2429 static struct attribute *md_default_attrs[] = {
2430         &md_level.attr,
2431         &md_raid_disks.attr,
2432         &md_chunk_size.attr,
2433         &md_size.attr,
2434         &md_metadata.attr,
2435         &md_new_device.attr,
2436         NULL,
2437 };
2438
2439 static struct attribute *md_redundancy_attrs[] = {
2440         &md_scan_mode.attr,
2441         &md_mismatches.attr,
2442         &md_sync_min.attr,
2443         &md_sync_max.attr,
2444         &md_sync_speed.attr,
2445         &md_sync_completed.attr,
2446         &md_suspend_lo.attr,
2447         &md_suspend_hi.attr,
2448         NULL,
2449 };
2450 static struct attribute_group md_redundancy_group = {
2451         .name = NULL,
2452         .attrs = md_redundancy_attrs,
2453 };
2454
2455
2456 static ssize_t
2457 md_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
2458 {
2459         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
2460         mddev_t *mddev = container_of(kobj, struct mddev_s, kobj);
2461         ssize_t rv;
2462
2463         if (!entry->show)
2464                 return -EIO;
2465         rv = mddev_lock(mddev);
2466         if (!rv) {
2467                 rv = entry->show(mddev, page);
2468                 mddev_unlock(mddev);
2469         }
2470         return rv;
2471 }
2472
2473 static ssize_t
2474 md_attr_store(struct kobject *kobj, struct attribute *attr,
2475               const char *page, size_t length)
2476 {
2477         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
2478         mddev_t *mddev = container_of(kobj, struct mddev_s, kobj);
2479         ssize_t rv;
2480
2481         if (!entry->store)
2482                 return -EIO;
2483         rv = mddev_lock(mddev);
2484         if (!rv) {
2485                 rv = entry->store(mddev, page, length);
2486                 mddev_unlock(mddev);
2487         }
2488         return rv;
2489 }
2490
2491 static void md_free(struct kobject *ko)
2492 {
2493         mddev_t *mddev = container_of(ko, mddev_t, kobj);
2494         kfree(mddev);
2495 }
2496
2497 static struct sysfs_ops md_sysfs_ops = {
2498         .show   = md_attr_show,
2499         .store  = md_attr_store,
2500 };
2501 static struct kobj_type md_ktype = {
2502         .release        = md_free,
2503         .sysfs_ops      = &md_sysfs_ops,
2504         .default_attrs  = md_default_attrs,
2505 };
2506
2507 int mdp_major = 0;
2508
2509 static struct kobject *md_probe(dev_t dev, int *part, void *data)
2510 {
2511         static DEFINE_MUTEX(disks_mutex);
2512         mddev_t *mddev = mddev_find(dev);
2513         struct gendisk *disk;
2514         int partitioned = (MAJOR(dev) != MD_MAJOR);
2515         int shift = partitioned ? MdpMinorShift : 0;
2516         int unit = MINOR(dev) >> shift;
2517
2518         if (!mddev)
2519                 return NULL;
2520
2521         mutex_lock(&disks_mutex);
2522         if (mddev->gendisk) {
2523                 mutex_unlock(&disks_mutex);
2524                 mddev_put(mddev);
2525                 return NULL;
2526         }
2527         disk = alloc_disk(1 << shift);
2528         if (!disk) {
2529                 mutex_unlock(&disks_mutex);
2530                 mddev_put(mddev);
2531                 return NULL;
2532         }
2533         disk->major = MAJOR(dev);
2534         disk->first_minor = unit << shift;
2535         if (partitioned) {
2536                 sprintf(disk->disk_name, "md_d%d", unit);
2537                 sprintf(disk->devfs_name, "md/d%d", unit);
2538         } else {
2539                 sprintf(disk->disk_name, "md%d", unit);
2540                 sprintf(disk->devfs_name, "md/%d", unit);
2541         }
2542         disk->fops = &md_fops;
2543         disk->private_data = mddev;
2544         disk->queue = mddev->queue;
2545         add_disk(disk);
2546         mddev->gendisk = disk;
2547         mutex_unlock(&disks_mutex);
2548         mddev->kobj.parent = &disk->kobj;
2549         mddev->kobj.k_name = NULL;
2550         snprintf(mddev->kobj.name, KOBJ_NAME_LEN, "%s", "md");
2551         mddev->kobj.ktype = &md_ktype;
2552         kobject_register(&mddev->kobj);
2553         return NULL;
2554 }
2555
2556 void md_wakeup_thread(mdk_thread_t *thread);
2557
2558 static void md_safemode_timeout(unsigned long data)
2559 {
2560         mddev_t *mddev = (mddev_t *) data;
2561
2562         mddev->safemode = 1;
2563         md_wakeup_thread(mddev->thread);
2564 }
2565
2566 static int start_dirty_degraded;
2567
2568 static int do_md_run(mddev_t * mddev)
2569 {
2570         int err;
2571         int chunk_size;
2572         struct list_head *tmp;
2573         mdk_rdev_t *rdev;
2574         struct gendisk *disk;
2575         struct mdk_personality *pers;
2576         char b[BDEVNAME_SIZE];
2577
2578         if (list_empty(&mddev->disks))
2579                 /* cannot run an array with no devices.. */
2580                 return -EINVAL;
2581
2582         if (mddev->pers)
2583                 return -EBUSY;
2584
2585         /*
2586          * Analyze all RAID superblock(s)
2587          */
2588         if (!mddev->raid_disks)
2589                 analyze_sbs(mddev);
2590
2591         chunk_size = mddev->chunk_size;
2592
2593         if (chunk_size) {
2594                 if (chunk_size > MAX_CHUNK_SIZE) {
2595                         printk(KERN_ERR "too big chunk_size: %d > %d\n",
2596                                 chunk_size, MAX_CHUNK_SIZE);
2597                         return -EINVAL;
2598                 }
2599                 /*
2600                  * chunk-size has to be a power of 2 and multiples of PAGE_SIZE
2601                  */
2602                 if ( (1 << ffz(~chunk_size)) != chunk_size) {
2603                         printk(KERN_ERR "chunk_size of %d not valid\n", chunk_size);
2604                         return -EINVAL;
2605                 }
2606                 if (chunk_size < PAGE_SIZE) {
2607                         printk(KERN_ERR "too small chunk_size: %d < %ld\n",
2608                                 chunk_size, PAGE_SIZE);
2609                         return -EINVAL;
2610                 }
2611
2612                 /* devices must have minimum size of one chunk */
2613                 ITERATE_RDEV(mddev,rdev,tmp) {
2614                         if (test_bit(Faulty, &rdev->flags))
2615                                 continue;
2616                         if (rdev->size < chunk_size / 1024) {
2617                                 printk(KERN_WARNING
2618                                         "md: Dev %s smaller than chunk_size:"
2619                                         " %lluk < %dk\n",
2620                                         bdevname(rdev->bdev,b),
2621                                         (unsigned long long)rdev->size,
2622                                         chunk_size / 1024);
2623                                 return -EINVAL;
2624                         }
2625                 }
2626         }
2627
2628 #ifdef CONFIG_KMOD
2629         if (mddev->level != LEVEL_NONE)
2630                 request_module("md-level-%d", mddev->level);
2631         else if (mddev->clevel[0])
2632                 request_module("md-%s", mddev->clevel);
2633 #endif
2634
2635         /*
2636          * Drop all container device buffers, from now on
2637          * the only valid external interface is through the md
2638          * device.
2639          * Also find largest hardsector size
2640          */
2641         ITERATE_RDEV(mddev,rdev,tmp) {
2642                 if (test_bit(Faulty, &rdev->flags))
2643                         continue;
2644                 sync_blockdev(rdev->bdev);
2645                 invalidate_bdev(rdev->bdev, 0);
2646         }
2647
2648         md_probe(mddev->unit, NULL, NULL);
2649         disk = mddev->gendisk;
2650         if (!disk)
2651                 return -ENOMEM;
2652
2653         spin_lock(&pers_lock);
2654         pers = find_pers(mddev->level, mddev->clevel);
2655         if (!pers || !try_module_get(pers->owner)) {
2656                 spin_unlock(&pers_lock);
2657                 if (mddev->level != LEVEL_NONE)
2658                         printk(KERN_WARNING "md: personality for level %d is not loaded!\n",
2659                                mddev->level);
2660                 else
2661                         printk(KERN_WARNING "md: personality for level %s is not loaded!\n",
2662                                mddev->clevel);
2663                 return -EINVAL;
2664         }
2665         mddev->pers = pers;
2666         spin_unlock(&pers_lock);
2667         mddev->level = pers->level;
2668         strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
2669
2670         if (mddev->reshape_position != MaxSector &&
2671             pers->start_reshape == NULL) {
2672                 /* This personality cannot handle reshaping... */
2673                 mddev->pers = NULL;
2674                 module_put(pers->owner);
2675                 return -EINVAL;
2676         }
2677
2678         mddev->recovery = 0;
2679         mddev->resync_max_sectors = mddev->size << 1; /* may be over-ridden by personality */
2680         mddev->barriers_work = 1;
2681         mddev->ok_start_degraded = start_dirty_degraded;
2682
2683         if (start_readonly)
2684                 mddev->ro = 2; /* read-only, but switch on first write */
2685
2686         err = mddev->pers->run(mddev);
2687         if (!err && mddev->pers->sync_request) {
2688                 err = bitmap_create(mddev);
2689                 if (err) {
2690                         printk(KERN_ERR "%s: failed to create bitmap (%d)\n",
2691                                mdname(mddev), err);
2692                         mddev->pers->stop(mddev);
2693                 }
2694         }
2695         if (err) {
2696                 printk(KERN_ERR "md: pers->run() failed ...\n");
2697                 module_put(mddev->pers->owner);
2698                 mddev->pers = NULL;
2699                 bitmap_destroy(mddev);
2700                 return err;
2701         }
2702         if (mddev->pers->sync_request)
2703                 sysfs_create_group(&mddev->kobj, &md_redundancy_group);
2704         else if (mddev->ro == 2) /* auto-readonly not meaningful */
2705                 mddev->ro = 0;
2706
2707         atomic_set(&mddev->writes_pending,0);
2708         mddev->safemode = 0;
2709         mddev->safemode_timer.function = md_safemode_timeout;
2710         mddev->safemode_timer.data = (unsigned long) mddev;
2711         mddev->safemode_delay = (20 * HZ)/1000 +1; /* 20 msec delay */
2712         mddev->in_sync = 1;
2713
2714         ITERATE_RDEV(mddev,rdev,tmp)
2715                 if (rdev->raid_disk >= 0) {
2716                         char nm[20];
2717                         sprintf(nm, "rd%d", rdev->raid_disk);
2718                         sysfs_create_link(&mddev->kobj, &rdev->kobj, nm);
2719                 }
2720
2721         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2722         md_wakeup_thread(mddev->thread);
2723
2724         if (mddev->sb_dirty)
2725                 md_update_sb(mddev);
2726
2727         set_capacity(disk, mddev->array_size<<1);
2728
2729         /* If we call blk_queue_make_request here, it will
2730          * re-initialise max_sectors etc which may have been
2731          * refined inside -> run.  So just set the bits we need to set.
2732          * Most initialisation happended when we called
2733          * blk_queue_make_request(..., md_fail_request)
2734          * earlier.
2735          */
2736         mddev->queue->queuedata = mddev;
2737         mddev->queue->make_request_fn = mddev->pers->make_request;
2738
2739         mddev->changed = 1;
2740         md_new_event(mddev);
2741         return 0;
2742 }
2743
2744 static int restart_array(mddev_t *mddev)
2745 {
2746         struct gendisk *disk = mddev->gendisk;
2747         int err;
2748
2749         /*
2750          * Complain if it has no devices
2751          */
2752         err = -ENXIO;
2753         if (list_empty(&mddev->disks))
2754                 goto out;
2755
2756         if (mddev->pers) {
2757                 err = -EBUSY;
2758                 if (!mddev->ro)
2759                         goto out;
2760
2761                 mddev->safemode = 0;
2762                 mddev->ro = 0;
2763                 set_disk_ro(disk, 0);
2764
2765                 printk(KERN_INFO "md: %s switched to read-write mode.\n",
2766                         mdname(mddev));
2767                 /*
2768                  * Kick recovery or resync if necessary
2769                  */
2770                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2771                 md_wakeup_thread(mddev->thread);
2772                 err = 0;
2773         } else {
2774                 printk(KERN_ERR "md: %s has no personality assigned.\n",
2775                         mdname(mddev));
2776                 err = -EINVAL;
2777         }
2778
2779 out:
2780         return err;
2781 }
2782
2783 static int do_md_stop(mddev_t * mddev, int ro)
2784 {
2785         int err = 0;
2786         struct gendisk *disk = mddev->gendisk;
2787
2788         if (mddev->pers) {
2789                 if (atomic_read(&mddev->active)>2) {
2790                         printk("md: %s still in use.\n",mdname(mddev));
2791                         return -EBUSY;
2792                 }
2793
2794                 if (mddev->sync_thread) {
2795                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2796                         md_unregister_thread(mddev->sync_thread);
2797                         mddev->sync_thread = NULL;
2798                 }
2799
2800                 del_timer_sync(&mddev->safemode_timer);
2801
2802                 invalidate_partition(disk, 0);
2803
2804                 if (ro) {
2805                         err  = -ENXIO;
2806                         if (mddev->ro==1)
2807                                 goto out;
2808                         mddev->ro = 1;
2809                 } else {
2810                         bitmap_flush(mddev);
2811                         md_super_wait(mddev);
2812                         if (mddev->ro)
2813                                 set_disk_ro(disk, 0);
2814                         blk_queue_make_request(mddev->queue, md_fail_request);
2815                         mddev->pers->stop(mddev);
2816                         if (mddev->pers->sync_request)
2817                                 sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
2818
2819                         module_put(mddev->pers->owner);
2820                         mddev->pers = NULL;
2821                         if (mddev->ro)
2822                                 mddev->ro = 0;
2823                 }
2824                 if (!mddev->in_sync) {
2825                         /* mark array as shutdown cleanly */
2826                         mddev->in_sync = 1;
2827                         md_update_sb(mddev);
2828                 }
2829                 if (ro)
2830                         set_disk_ro(disk, 1);
2831         }
2832
2833         /*
2834          * Free resources if final stop
2835          */
2836         if (!ro) {
2837                 mdk_rdev_t *rdev;
2838                 struct list_head *tmp;
2839                 struct gendisk *disk;
2840                 printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
2841
2842                 bitmap_destroy(mddev);
2843                 if (mddev->bitmap_file) {
2844                         atomic_set(&mddev->bitmap_file->f_dentry->d_inode->i_writecount, 1);
2845                         fput(mddev->bitmap_file);
2846                         mddev->bitmap_file = NULL;
2847                 }
2848                 mddev->bitmap_offset = 0;
2849
2850                 ITERATE_RDEV(mddev,rdev,tmp)
2851                         if (rdev->raid_disk >= 0) {
2852                                 char nm[20];
2853                                 sprintf(nm, "rd%d", rdev->raid_disk);
2854                                 sysfs_remove_link(&mddev->kobj, nm);
2855                         }
2856
2857                 export_array(mddev);
2858
2859                 mddev->array_size = 0;
2860                 disk = mddev->gendisk;
2861                 if (disk)
2862                         set_capacity(disk, 0);
2863                 mddev->changed = 1;
2864         } else
2865                 printk(KERN_INFO "md: %s switched to read-only mode.\n",
2866                         mdname(mddev));
2867         err = 0;
2868         md_new_event(mddev);
2869 out:
2870         return err;
2871 }
2872
2873 static void autorun_array(mddev_t *mddev)
2874 {
2875         mdk_rdev_t *rdev;
2876         struct list_head *tmp;
2877         int err;
2878
2879         if (list_empty(&mddev->disks))
2880                 return;
2881
2882         printk(KERN_INFO "md: running: ");
2883
2884         ITERATE_RDEV(mddev,rdev,tmp) {
2885                 char b[BDEVNAME_SIZE];
2886                 printk("<%s>", bdevname(rdev->bdev,b));
2887         }
2888         printk("\n");
2889
2890         err = do_md_run (mddev);
2891         if (err) {
2892                 printk(KERN_WARNING "md: do_md_run() returned %d\n", err);
2893                 do_md_stop (mddev, 0);
2894         }
2895 }
2896
2897 /*
2898  * lets try to run arrays based on all disks that have arrived
2899  * until now. (those are in pending_raid_disks)
2900  *
2901  * the method: pick the first pending disk, collect all disks with
2902  * the same UUID, remove all from the pending list and put them into
2903  * the 'same_array' list. Then order this list based on superblock
2904  * update time (freshest comes first), kick out 'old' disks and
2905  * compare superblocks. If everything's fine then run it.
2906  *
2907  * If "unit" is allocated, then bump its reference count
2908  */
2909 static void autorun_devices(int part)
2910 {
2911         struct list_head *tmp;
2912         mdk_rdev_t *rdev0, *rdev;
2913         mddev_t *mddev;
2914         char b[BDEVNAME_SIZE];
2915
2916         printk(KERN_INFO "md: autorun ...\n");
2917         while (!list_empty(&pending_raid_disks)) {
2918                 dev_t dev;
2919                 LIST_HEAD(candidates);
2920                 rdev0 = list_entry(pending_raid_disks.next,
2921                                          mdk_rdev_t, same_set);
2922
2923                 printk(KERN_INFO "md: considering %s ...\n",
2924                         bdevname(rdev0->bdev,b));
2925                 INIT_LIST_HEAD(&candidates);
2926                 ITERATE_RDEV_PENDING(rdev,tmp)
2927                         if (super_90_load(rdev, rdev0, 0) >= 0) {
2928                                 printk(KERN_INFO "md:  adding %s ...\n",
2929                                         bdevname(rdev->bdev,b));
2930                                 list_move(&rdev->same_set, &candidates);
2931                         }
2932                 /*
2933                  * now we have a set of devices, with all of them having
2934                  * mostly sane superblocks. It's time to allocate the
2935                  * mddev.
2936                  */
2937                 if (rdev0->preferred_minor < 0 || rdev0->preferred_minor >= MAX_MD_DEVS) {
2938                         printk(KERN_INFO "md: unit number in %s is bad: %d\n",
2939                                bdevname(rdev0->bdev, b), rdev0->preferred_minor);
2940                         break;
2941                 }
2942                 if (part)
2943                         dev = MKDEV(mdp_major,
2944                                     rdev0->preferred_minor << MdpMinorShift);
2945                 else
2946                         dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
2947
2948                 md_probe(dev, NULL, NULL);
2949                 mddev = mddev_find(dev);
2950                 if (!mddev) {
2951                         printk(KERN_ERR
2952                                 "md: cannot allocate memory for md drive.\n");
2953                         break;
2954                 }
2955                 if (mddev_lock(mddev))
2956                         printk(KERN_WARNING "md: %s locked, cannot run\n",
2957                                mdname(mddev));
2958                 else if (mddev->raid_disks || mddev->major_version
2959                          || !list_empty(&mddev->disks)) {
2960                         printk(KERN_WARNING
2961                                 "md: %s already running, cannot run %s\n",
2962                                 mdname(mddev), bdevname(rdev0->bdev,b));
2963                         mddev_unlock(mddev);
2964                 } else {
2965                         printk(KERN_INFO "md: created %s\n", mdname(mddev));
2966                         ITERATE_RDEV_GENERIC(candidates,rdev,tmp) {
2967                                 list_del_init(&rdev->same_set);
2968                                 if (bind_rdev_to_array(rdev, mddev))
2969                                         export_rdev(rdev);
2970                         }
2971                         autorun_array(mddev);
2972                         mddev_unlock(mddev);
2973                 }
2974                 /* on success, candidates will be empty, on error
2975                  * it won't...
2976                  */
2977                 ITERATE_RDEV_GENERIC(candidates,rdev,tmp)
2978                         export_rdev(rdev);
2979                 mddev_put(mddev);
2980         }
2981         printk(KERN_INFO "md: ... autorun DONE.\n");
2982 }
2983
2984 /*
2985  * import RAID devices based on one partition
2986  * if possible, the array gets run as well.
2987  */
2988
2989 static int autostart_array(dev_t startdev)
2990 {
2991         char b[BDEVNAME_SIZE];
2992         int err = -EINVAL, i;
2993         mdp_super_t *sb = NULL;
2994         mdk_rdev_t *start_rdev = NULL, *rdev;
2995
2996         start_rdev = md_import_device(startdev, 0, 0);
2997         if (IS_ERR(start_rdev))
2998                 return err;
2999
3000
3001         /* NOTE: this can only work for 0.90.0 superblocks */
3002         sb = (mdp_super_t*)page_address(start_rdev->sb_page);
3003         if (sb->major_version != 0 ||
3004             sb->minor_version != 90 ) {
3005                 printk(KERN_WARNING "md: can only autostart 0.90.0 arrays\n");
3006                 export_rdev(start_rdev);
3007                 return err;
3008         }
3009
3010         if (test_bit(Faulty, &start_rdev->flags)) {
3011                 printk(KERN_WARNING
3012                         "md: can not autostart based on faulty %s!\n",
3013                         bdevname(start_rdev->bdev,b));
3014                 export_rdev(start_rdev);
3015                 return err;
3016         }
3017         list_add(&start_rdev->same_set, &pending_raid_disks);
3018
3019         for (i = 0; i < MD_SB_DISKS; i++) {
3020                 mdp_disk_t *desc = sb->disks + i;
3021                 dev_t dev = MKDEV(desc->major, desc->minor);
3022
3023                 if (!dev)
3024                         continue;
3025                 if (dev == startdev)
3026                         continue;
3027                 if (MAJOR(dev) != desc->major || MINOR(dev) != desc->minor)
3028                         continue;
3029                 rdev = md_import_device(dev, 0, 0);
3030                 if (IS_ERR(rdev))
3031                         continue;
3032
3033                 list_add(&rdev->same_set, &pending_raid_disks);
3034         }
3035
3036         /*
3037          * possibly return codes
3038          */
3039         autorun_devices(0);
3040         return 0;
3041
3042 }
3043
3044
3045 static int get_version(void __user * arg)
3046 {
3047         mdu_version_t ver;
3048
3049         ver.major = MD_MAJOR_VERSION;
3050         ver.minor = MD_MINOR_VERSION;
3051         ver.patchlevel = MD_PATCHLEVEL_VERSION;
3052
3053         if (copy_to_user(arg, &ver, sizeof(ver)))
3054                 return -EFAULT;
3055
3056         return 0;
3057 }
3058
3059 static int get_array_info(mddev_t * mddev, void __user * arg)
3060 {
3061         mdu_array_info_t info;
3062         int nr,working,active,failed,spare;
3063         mdk_rdev_t *rdev;
3064         struct list_head *tmp;
3065
3066         nr=working=active=failed=spare=0;
3067         ITERATE_RDEV(mddev,rdev,tmp) {
3068                 nr++;
3069                 if (test_bit(Faulty, &rdev->flags))
3070                         failed++;
3071                 else {
3072                         working++;
3073                         if (test_bit(In_sync, &rdev->flags))
3074                                 active++;
3075                         else
3076                                 spare++;
3077                 }
3078         }
3079
3080         info.major_version = mddev->major_version;
3081         info.minor_version = mddev->minor_version;
3082         info.patch_version = MD_PATCHLEVEL_VERSION;
3083         info.ctime         = mddev->ctime;
3084         info.level         = mddev->level;
3085         info.size          = mddev->size;
3086         if (info.size != mddev->size) /* overflow */
3087                 info.size = -1;
3088         info.nr_disks      = nr;
3089         info.raid_disks    = mddev->raid_disks;
3090         info.md_minor      = mddev->md_minor;
3091         info.not_persistent= !mddev->persistent;
3092
3093         info.utime         = mddev->utime;
3094         info.state         = 0;
3095         if (mddev->in_sync)
3096                 info.state = (1<<MD_SB_CLEAN);
3097         if (mddev->bitmap && mddev->bitmap_offset)
3098                 info.state = (1<<MD_SB_BITMAP_PRESENT);
3099         info.active_disks  = active;
3100         info.working_disks = working;
3101         info.failed_disks  = failed;
3102         info.spare_disks   = spare;
3103
3104         info.layout        = mddev->layout;
3105         info.chunk_size    = mddev->chunk_size;
3106
3107         if (copy_to_user(arg, &info, sizeof(info)))
3108                 return -EFAULT;
3109
3110         return 0;
3111 }
3112
3113 static int get_bitmap_file(mddev_t * mddev, void __user * arg)
3114 {
3115         mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
3116         char *ptr, *buf = NULL;
3117         int err = -ENOMEM;
3118
3119         file = kmalloc(sizeof(*file), GFP_KERNEL);
3120         if (!file)
3121                 goto out;
3122
3123         /* bitmap disabled, zero the first byte and copy out */
3124         if (!mddev->bitmap || !mddev->bitmap->file) {
3125                 file->pathname[0] = '\0';
3126                 goto copy_out;
3127         }
3128
3129         buf = kmalloc(sizeof(file->pathname), GFP_KERNEL);
3130         if (!buf)
3131                 goto out;
3132
3133         ptr = file_path(mddev->bitmap->file, buf, sizeof(file->pathname));
3134         if (!ptr)
3135                 goto out;
3136
3137         strcpy(file->pathname, ptr);
3138
3139 copy_out:
3140         err = 0;
3141         if (copy_to_user(arg, file, sizeof(*file)))
3142                 err = -EFAULT;
3143 out:
3144         kfree(buf);
3145         kfree(file);
3146         return err;
3147 }
3148
3149 static int get_disk_info(mddev_t * mddev, void __user * arg)
3150 {
3151         mdu_disk_info_t info;
3152         unsigned int nr;
3153         mdk_rdev_t *rdev;
3154
3155         if (copy_from_user(&info, arg, sizeof(info)))
3156                 return -EFAULT;
3157
3158         nr = info.number;
3159
3160         rdev = find_rdev_nr(mddev, nr);
3161         if (rdev) {
3162                 info.major = MAJOR(rdev->bdev->bd_dev);
3163                 info.minor = MINOR(rdev->bdev->bd_dev);
3164                 info.raid_disk = rdev->raid_disk;
3165                 info.state = 0;
3166                 if (test_bit(Faulty, &rdev->flags))
3167                         info.state |= (1<<MD_DISK_FAULTY);
3168                 else if (test_bit(In_sync, &rdev->flags)) {
3169                         info.state |= (1<<MD_DISK_ACTIVE);
3170                         info.state |= (1<<MD_DISK_SYNC);
3171                 }
3172                 if (test_bit(WriteMostly, &rdev->flags))
3173                         info.state |= (1<<MD_DISK_WRITEMOSTLY);
3174         } else {
3175                 info.major = info.minor = 0;
3176                 info.raid_disk = -1;
3177                 info.state = (1<<MD_DISK_REMOVED);
3178         }
3179
3180         if (copy_to_user(arg, &info, sizeof(info)))
3181                 return -EFAULT;
3182
3183         return 0;
3184 }
3185
3186 static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
3187 {
3188         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
3189         mdk_rdev_t *rdev;
3190         dev_t dev = MKDEV(info->major,info->minor);
3191
3192         if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
3193                 return -EOVERFLOW;
3194
3195         if (!mddev->raid_disks) {
3196                 int err;
3197                 /* expecting a device which has a superblock */
3198                 rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
3199                 if (IS_ERR(rdev)) {
3200                         printk(KERN_WARNING
3201                                 "md: md_import_device returned %ld\n",
3202                                 PTR_ERR(rdev));
3203                         return PTR_ERR(rdev);
3204                 }
3205                 if (!list_empty(&mddev->disks)) {
3206                         mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
3207                                                         mdk_rdev_t, same_set);
3208                         int err = super_types[mddev->major_version]
3209                                 .load_super(rdev, rdev0, mddev->minor_version);
3210                         if (err < 0) {
3211                                 printk(KERN_WARNING
3212                                         "md: %s has different UUID to %s\n",
3213                                         bdevname(rdev->bdev,b),
3214                                         bdevname(rdev0->bdev,b2));
3215                                 export_rdev(rdev);
3216                                 return -EINVAL;
3217                         }
3218                 }
3219                 err = bind_rdev_to_array(rdev, mddev);
3220                 if (err)
3221                         export_rdev(rdev);
3222                 return err;
3223         }
3224
3225         /*
3226          * add_new_disk can be used once the array is assembled
3227          * to add "hot spares".  They must already have a superblock
3228          * written
3229          */
3230         if (mddev->pers) {
3231                 int err;
3232                 if (!mddev->pers->hot_add_disk) {
3233                         printk(KERN_WARNING
3234                                 "%s: personality does not support diskops!\n",
3235                                mdname(mddev));
3236                         return -EINVAL;
3237                 }
3238                 if (mddev->persistent)
3239                         rdev = md_import_device(dev, mddev->major_version,
3240                                                 mddev->minor_version);
3241                 else
3242                         rdev = md_import_device(dev, -1, -1);
3243                 if (IS_ERR(rdev)) {
3244                         printk(KERN_WARNING
3245                                 "md: md_import_device returned %ld\n",
3246                                 PTR_ERR(rdev));
3247                         return PTR_ERR(rdev);
3248                 }
3249                 /* set save_raid_disk if appropriate */
3250                 if (!mddev->persistent) {
3251                         if (info->state & (1<<MD_DISK_SYNC)  &&
3252                             info->raid_disk < mddev->raid_disks)
3253                                 rdev->raid_disk = info->raid_disk;
3254                         else
3255                                 rdev->raid_disk = -1;
3256                 } else
3257                         super_types[mddev->major_version].
3258                                 validate_super(mddev, rdev);
3259                 rdev->saved_raid_disk = rdev->raid_disk;
3260
3261                 clear_bit(In_sync, &rdev->flags); /* just to be sure */
3262                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
3263                         set_bit(WriteMostly, &rdev->flags);
3264
3265                 rdev->raid_disk = -1;
3266                 err = bind_rdev_to_array(rdev, mddev);
3267                 if (err)
3268                         export_rdev(rdev);
3269
3270                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3271                 md_wakeup_thread(mddev->thread);
3272                 return err;
3273         }
3274
3275         /* otherwise, add_new_disk is only allowed
3276          * for major_version==0 superblocks
3277          */
3278         if (mddev->major_version != 0) {
3279                 printk(KERN_WARNING "%s: ADD_NEW_DISK not supported\n",
3280                        mdname(mddev));
3281                 return -EINVAL;
3282         }
3283
3284         if (!(info->state & (1<<MD_DISK_FAULTY))) {
3285                 int err;
3286                 rdev = md_import_device (dev, -1, 0);
3287                 if (IS_ERR(rdev)) {
3288                         printk(KERN_WARNING
3289                                 "md: error, md_import_device() returned %ld\n",
3290                                 PTR_ERR(rdev));
3291                         return PTR_ERR(rdev);
3292                 }
3293                 rdev->desc_nr = info->number;
3294                 if (info->raid_disk < mddev->raid_disks)
3295                         rdev->raid_disk = info->raid_disk;
3296                 else
3297                         rdev->raid_disk = -1;
3298
3299                 rdev->flags = 0;
3300
3301                 if (rdev->raid_disk < mddev->raid_disks)
3302                         if (info->state & (1<<MD_DISK_SYNC))
3303                                 set_bit(In_sync, &rdev->flags);
3304
3305                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
3306                         set_bit(WriteMostly, &rdev->flags);
3307
3308                 if (!mddev->persistent) {
3309                         printk(KERN_INFO "md: nonpersistent superblock ...\n");
3310                         rdev->sb_offset = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
3311                 } else
3312                         rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
3313                 rdev->size = calc_dev_size(rdev, mddev->chunk_size);
3314
3315                 err = bind_rdev_to_array(rdev, mddev);
3316                 if (err) {
3317                         export_rdev(rdev);
3318                         return err;
3319                 }
3320         }
3321
3322         return 0;
3323 }
3324
3325 static int hot_remove_disk(mddev_t * mddev, dev_t dev)
3326 {
3327         char b[BDEVNAME_SIZE];
3328         mdk_rdev_t *rdev;
3329
3330         if (!mddev->pers)
3331                 return -ENODEV;
3332
3333         rdev = find_rdev(mddev, dev);
3334         if (!rdev)
3335                 return -ENXIO;
3336
3337         if (rdev->raid_disk >= 0)
3338                 goto busy;
3339
3340         kick_rdev_from_array(rdev);
3341         md_update_sb(mddev);
3342         md_new_event(mddev);
3343
3344         return 0;
3345 busy:
3346         printk(KERN_WARNING "md: cannot remove active disk %s from %s ... \n",
3347                 bdevname(rdev->bdev,b), mdname(mddev));
3348         return -EBUSY;
3349 }
3350
3351 static int hot_add_disk(mddev_t * mddev, dev_t dev)
3352 {
3353         char b[BDEVNAME_SIZE];
3354         int err;
3355         unsigned int size;
3356         mdk_rdev_t *rdev;
3357
3358         if (!mddev->pers)
3359                 return -ENODEV;
3360
3361         if (mddev->major_version != 0) {
3362                 printk(KERN_WARNING "%s: HOT_ADD may only be used with"
3363                         " version-0 superblocks.\n",
3364                         mdname(mddev));
3365                 return -EINVAL;
3366         }
3367         if (!mddev->pers->hot_add_disk) {
3368                 printk(KERN_WARNING
3369                         "%s: personality does not support diskops!\n",
3370                         mdname(mddev));
3371                 return -EINVAL;
3372         }
3373
3374         rdev = md_import_device (dev, -1, 0);
3375         if (IS_ERR(rdev)) {
3376                 printk(KERN_WARNING
3377                         "md: error, md_import_device() returned %ld\n",
3378                         PTR_ERR(rdev));
3379                 return -EINVAL;
3380         }
3381
3382         if (mddev->persistent)
3383                 rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
3384         else
3385                 rdev->sb_offset =
3386                         rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
3387
3388         size = calc_dev_size(rdev, mddev->chunk_size);
3389         rdev->size = size;
3390
3391         if (test_bit(Faulty, &rdev->flags)) {
3392                 printk(KERN_WARNING
3393                         "md: can not hot-add faulty %s disk to %s!\n",
3394                         bdevname(rdev->bdev,b), mdname(mddev));
3395                 err = -EINVAL;
3396                 goto abort_export;
3397         }
3398         clear_bit(In_sync, &rdev->flags);
3399         rdev->desc_nr = -1;
3400         err = bind_rdev_to_array(rdev, mddev);
3401         if (err)
3402                 goto abort_export;
3403
3404         /*
3405          * The rest should better be atomic, we can have disk failures
3406          * noticed in interrupt contexts ...
3407          */
3408
3409         if (rdev->desc_nr == mddev->max_disks) {
3410                 printk(KERN_WARNING "%s: can not hot-add to full array!\n",
3411                         mdname(mddev));
3412                 err = -EBUSY;
3413                 goto abort_unbind_export;
3414         }
3415
3416         rdev->raid_disk = -1;
3417
3418         md_update_sb(mddev);
3419
3420         /*
3421          * Kick recovery, maybe this spare has to be added to the
3422          * array immediately.
3423          */
3424         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3425         md_wakeup_thread(mddev->thread);
3426         md_new_event(mddev);
3427         return 0;
3428
3429 abort_unbind_export:
3430         unbind_rdev_from_array(rdev);
3431
3432 abort_export:
3433         export_rdev(rdev);
3434         return err;
3435 }
3436
3437 /* similar to deny_write_access, but accounts for our holding a reference
3438  * to the file ourselves */
3439 static int deny_bitmap_write_access(struct file * file)
3440 {
3441         struct inode *inode = file->f_mapping->host;
3442
3443         spin_lock(&inode->i_lock);
3444         if (atomic_read(&inode->i_writecount) > 1) {
3445                 spin_unlock(&inode->i_lock);
3446                 return -ETXTBSY;
3447         }
3448         atomic_set(&inode->i_writecount, -1);
3449         spin_unlock(&inode->i_lock);
3450
3451         return 0;
3452 }
3453
3454 static int set_bitmap_file(mddev_t *mddev, int fd)
3455 {
3456         int err;
3457
3458         if (mddev->pers) {
3459                 if (!mddev->pers->quiesce)
3460                         return -EBUSY;
3461                 if (mddev->recovery || mddev->sync_thread)
3462                         return -EBUSY;
3463                 /* we should be able to change the bitmap.. */
3464         }
3465
3466
3467         if (fd >= 0) {
3468                 if (mddev->bitmap)
3469                         return -EEXIST; /* cannot add when bitmap is present */
3470                 mddev->bitmap_file = fget(fd);
3471
3472                 if (mddev->bitmap_file == NULL) {
3473                         printk(KERN_ERR "%s: error: failed to get bitmap file\n",
3474                                mdname(mddev));
3475                         return -EBADF;
3476                 }
3477
3478                 err = deny_bitmap_write_access(mddev->bitmap_file);
3479                 if (err) {
3480                         printk(KERN_ERR "%s: error: bitmap file is already in use\n",
3481                                mdname(mddev));
3482                         fput(mddev->bitmap_file);
3483                         mddev->bitmap_file = NULL;
3484                         return err;
3485                 }
3486                 mddev->bitmap_offset = 0; /* file overrides offset */
3487         } else if (mddev->bitmap == NULL)
3488                 return -ENOENT; /* cannot remove what isn't there */
3489         err = 0;
3490         if (mddev->pers) {
3491                 mddev->pers->quiesce(mddev, 1);
3492                 if (fd >= 0)
3493                         err = bitmap_create(mddev);
3494                 if (fd < 0 || err)
3495                         bitmap_destroy(mddev);
3496                 mddev->pers->quiesce(mddev, 0);
3497         } else if (fd < 0) {
3498                 if (mddev->bitmap_file)
3499                         fput(mddev->bitmap_file);
3500                 mddev->bitmap_file = NULL;
3501         }
3502
3503         return err;
3504 }
3505
3506 /*
3507  * set_array_info is used two different ways
3508  * The original usage is when creating a new array.
3509  * In this usage, raid_disks is > 0 and it together with
3510  *  level, size, not_persistent,layout,chunksize determine the
3511  *  shape of the array.
3512  *  This will always create an array with a type-0.90.0 superblock.
3513  * The newer usage is when assembling an array.
3514  *  In this case raid_disks will be 0, and the major_version field is
3515  *  use to determine which style super-blocks are to be found on the devices.
3516  *  The minor and patch _version numbers are also kept incase the
3517  *  super_block handler wishes to interpret them.
3518  */
3519 static int set_array_info(mddev_t * mddev, mdu_array_info_t *info)
3520 {
3521
3522         if (info->raid_disks == 0) {
3523                 /* just setting version number for superblock loading */
3524                 if (info->major_version < 0 ||
3525                     info->major_version >= sizeof(super_types)/sizeof(super_types[0]) ||
3526                     super_types[info->major_version].name == NULL) {
3527                         /* maybe try to auto-load a module? */
3528                         printk(KERN_INFO
3529                                 "md: superblock version %d not known\n",
3530                                 info->major_version);
3531                         return -EINVAL;
3532                 }
3533                 mddev->major_version = info->major_version;
3534                 mddev->minor_version = info->minor_version;
3535                 mddev->patch_version = info->patch_version;
3536                 return 0;
3537         }
3538         mddev->major_version = MD_MAJOR_VERSION;
3539         mddev->minor_version = MD_MINOR_VERSION;
3540         mddev->patch_version = MD_PATCHLEVEL_VERSION;
3541         mddev->ctime         = get_seconds();
3542
3543         mddev->level         = info->level;
3544         mddev->clevel[0]     = 0;
3545         mddev->size          = info->size;
3546         mddev->raid_disks    = info->raid_disks;
3547         /* don't set md_minor, it is determined by which /dev/md* was
3548          * openned
3549          */
3550         if (info->state & (1<<MD_SB_CLEAN))
3551                 mddev->recovery_cp = MaxSector;
3552         else
3553                 mddev->recovery_cp = 0;
3554         mddev->persistent    = ! info->not_persistent;
3555
3556         mddev->layout        = info->layout;
3557         mddev->chunk_size    = info->chunk_size;
3558
3559         mddev->max_disks     = MD_SB_DISKS;
3560
3561         mddev->sb_dirty      = 1;
3562
3563         mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
3564         mddev->bitmap_offset = 0;
3565
3566         mddev->reshape_position = MaxSector;
3567
3568         /*
3569          * Generate a 128 bit UUID
3570          */
3571         get_random_bytes(mddev->uuid, 16);
3572
3573         mddev->new_level = mddev->level;
3574         mddev->new_chunk = mddev->chunk_size;
3575         mddev->new_layout = mddev->layout;
3576         mddev->delta_disks = 0;
3577
3578         return 0;
3579 }
3580
3581 static int update_size(mddev_t *mddev, unsigned long size)
3582 {
3583         mdk_rdev_t * rdev;
3584         int rv;
3585         struct list_head *tmp;
3586         int fit = (size == 0);
3587
3588         if (mddev->pers->resize == NULL)
3589                 return -EINVAL;
3590         /* The "size" is the amount of each device that is used.
3591          * This can only make sense for arrays with redundancy.
3592          * linear and raid0 always use whatever space is available
3593          * We can only consider changing the size if no resync
3594          * or reconstruction is happening, and if the new size
3595          * is acceptable. It must fit before the sb_offset or,
3596          * if that is <data_offset, it must fit before the
3597          * size of each device.
3598          * If size is zero, we find the largest size that fits.
3599          */
3600         if (mddev->sync_thread)
3601                 return -EBUSY;
3602         ITERATE_RDEV(mddev,rdev,tmp) {
3603                 sector_t avail;
3604                 if (rdev->sb_offset > rdev->data_offset)
3605                         avail = (rdev->sb_offset*2) - rdev->data_offset;
3606                 else
3607                         avail = get_capacity(rdev->bdev->bd_disk)
3608                                 - rdev->data_offset;
3609                 if (fit && (size == 0 || size > avail/2))
3610                         size = avail/2;
3611                 if (avail < ((sector_t)size << 1))
3612                         return -ENOSPC;
3613         }
3614         rv = mddev->pers->resize(mddev, (sector_t)size *2);
3615         if (!rv) {
3616                 struct block_device *bdev;
3617
3618                 bdev = bdget_disk(mddev->gendisk, 0);
3619                 if (bdev) {
3620                         mutex_lock(&bdev->bd_inode->i_mutex);
3621                         i_size_write(bdev->bd_inode, (loff_t)mddev->array_size << 10);
3622                         mutex_unlock(&bdev->bd_inode->i_mutex);
3623                         bdput(bdev);
3624                 }
3625         }
3626         return rv;
3627 }
3628
3629 static int update_raid_disks(mddev_t *mddev, int raid_disks)
3630 {
3631         int rv;
3632         /* change the number of raid disks */
3633         if (mddev->pers->check_reshape == NULL)
3634                 return -EINVAL;
3635         if (raid_disks <= 0 ||
3636             raid_disks >= mddev->max_disks)
3637                 return -EINVAL;
3638         if (mddev->sync_thread || mddev->reshape_position != MaxSector)
3639                 return -EBUSY;
3640         mddev->delta_disks = raid_disks - mddev->raid_disks;
3641
3642         rv = mddev->pers->check_reshape(mddev);
3643         return rv;
3644 }
3645
3646
3647 /*
3648  * update_array_info is used to change the configuration of an
3649  * on-line array.
3650  * The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
3651  * fields in the info are checked against the array.
3652  * Any differences that cannot be handled will cause an error.
3653  * Normally, only one change can be managed at a time.
3654  */
3655 static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
3656 {
3657         int rv = 0;
3658         int cnt = 0;
3659         int state = 0;
3660
3661         /* calculate expected state,ignoring low bits */
3662         if (mddev->bitmap && mddev->bitmap_offset)
3663                 state |= (1 << MD_SB_BITMAP_PRESENT);
3664
3665         if (mddev->major_version != info->major_version ||
3666             mddev->minor_version != info->minor_version ||
3667 /*          mddev->patch_version != info->patch_version || */
3668             mddev->ctime         != info->ctime         ||
3669             mddev->level         != info->level         ||
3670 /*          mddev->layout        != info->layout        || */
3671             !mddev->persistent   != info->not_persistent||
3672             mddev->chunk_size    != info->chunk_size    ||
3673             /* ignore bottom 8 bits of state, and allow SB_BITMAP_PRESENT to change */
3674             ((state^info->state) & 0xfffffe00)
3675                 )
3676                 return -EINVAL;
3677         /* Check there is only one change */
3678         if (info->size >= 0 && mddev->size != info->size) cnt++;
3679         if (mddev->raid_disks != info->raid_disks) cnt++;
3680         if (mddev->layout != info->layout) cnt++;
3681         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) cnt++;
3682         if (cnt == 0) return 0;
3683         if (cnt > 1) return -EINVAL;
3684
3685         if (mddev->layout != info->layout) {
3686                 /* Change layout
3687                  * we don't need to do anything at the md level, the
3688                  * personality will take care of it all.
3689                  */
3690                 if (mddev->pers->reconfig == NULL)
3691                         return -EINVAL;
3692                 else
3693                         return mddev->pers->reconfig(mddev, info->layout, -1);
3694         }
3695         if (info->size >= 0 && mddev->size != info->size)
3696                 rv = update_size(mddev, info->size);
3697
3698         if (mddev->raid_disks    != info->raid_disks)
3699                 rv = update_raid_disks(mddev, info->raid_disks);
3700
3701         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) {
3702                 if (mddev->pers->quiesce == NULL)
3703                         return -EINVAL;
3704                 if (mddev->recovery || mddev->sync_thread)
3705                         return -EBUSY;
3706                 if (info->state & (1<<MD_SB_BITMAP_PRESENT)) {
3707                         /* add the bitmap */
3708                         if (mddev->bitmap)
3709                                 return -EEXIST;
3710                         if (mddev->default_bitmap_offset == 0)
3711                                 return -EINVAL;
3712                         mddev->bitmap_offset = mddev->default_bitmap_offset;
3713                         mddev->pers->quiesce(mddev, 1);
3714                         rv = bitmap_create(mddev);
3715                         if (rv)
3716                                 bitmap_destroy(mddev);
3717                         mddev->pers->quiesce(mddev, 0);
3718                 } else {
3719                         /* remove the bitmap */
3720                         if (!mddev->bitmap)
3721                                 return -ENOENT;
3722                         if (mddev->bitmap->file)
3723                                 return -EINVAL;
3724                         mddev->pers->quiesce(mddev, 1);
3725                         bitmap_destroy(mddev);
3726                         mddev->pers->quiesce(mddev, 0);
3727                         mddev->bitmap_offset = 0;
3728                 }
3729         }
3730         md_update_sb(mddev);
3731         return rv;
3732 }
3733
3734 static int set_disk_faulty(mddev_t *mddev, dev_t dev)
3735 {
3736         mdk_rdev_t *rdev;
3737
3738         if (mddev->pers == NULL)
3739                 return -ENODEV;
3740
3741         rdev = find_rdev(mddev, dev);
3742         if (!rdev)
3743                 return -ENODEV;
3744
3745         md_error(mddev, rdev);
3746         return 0;
3747 }
3748
3749 static int md_getgeo(struct block_device *bdev, struct hd_geometry *geo)
3750 {
3751         mddev_t *mddev = bdev->bd_disk->private_data;
3752
3753         geo->heads = 2;
3754         geo->sectors = 4;
3755         geo->cylinders = get_capacity(mddev->gendisk) / 8;
3756         return 0;
3757 }
3758
3759 static int md_ioctl(struct inode *inode, struct file *file,
3760                         unsigned int cmd, unsigned long arg)
3761 {
3762         int err = 0;
3763         void __user *argp = (void __user *)arg;
3764         mddev_t *mddev = NULL;
3765
3766         if (!capable(CAP_SYS_ADMIN))
3767                 return -EACCES;
3768
3769         /*
3770          * Commands dealing with the RAID driver but not any
3771          * particular array:
3772          */
3773         switch (cmd)
3774         {
3775                 case RAID_VERSION:
3776                         err = get_version(argp);
3777                         goto done;
3778
3779                 case PRINT_RAID_DEBUG:
3780                         err = 0;
3781                         md_print_devices();
3782                         goto done;
3783
3784 #ifndef MODULE
3785                 case RAID_AUTORUN:
3786                         err = 0;
3787                         autostart_arrays(arg);
3788                         goto done;
3789 #endif
3790                 default:;
3791         }
3792
3793         /*
3794          * Commands creating/starting a new array:
3795          */
3796
3797         mddev = inode->i_bdev->bd_disk->private_data;
3798
3799         if (!mddev) {
3800                 BUG();
3801                 goto abort;
3802         }
3803
3804
3805         if (cmd == START_ARRAY) {
3806                 /* START_ARRAY doesn't need to lock the array as autostart_array
3807                  * does the locking, and it could even be a different array
3808                  */
3809                 static int cnt = 3;
3810                 if (cnt > 0 ) {
3811                         printk(KERN_WARNING
3812                                "md: %s(pid %d) used deprecated START_ARRAY ioctl. "
3813                                "This will not be supported beyond July 2006\n",
3814                                current->comm, current->pid);
3815                         cnt--;
3816                 }
3817                 err = autostart_array(new_decode_dev(arg));
3818                 if (err) {
3819                         printk(KERN_WARNING "md: autostart failed!\n");
3820                         goto abort;
3821                 }
3822                 goto done;
3823         }
3824
3825         err = mddev_lock(mddev);
3826         if (err) {
3827                 printk(KERN_INFO
3828                         "md: ioctl lock interrupted, reason %d, cmd %d\n",
3829                         err, cmd);
3830                 goto abort;
3831         }
3832
3833         switch (cmd)
3834         {
3835                 case SET_ARRAY_INFO:
3836                         {
3837                                 mdu_array_info_t info;
3838                                 if (!arg)
3839                                         memset(&info, 0, sizeof(info));
3840                                 else if (copy_from_user(&info, argp, sizeof(info))) {
3841                                         err = -EFAULT;
3842                                         goto abort_unlock;
3843                                 }
3844                                 if (mddev->pers) {
3845                                         err = update_array_info(mddev, &info);
3846                                         if (err) {
3847                                                 printk(KERN_WARNING "md: couldn't update"
3848                                                        " array info. %d\n", err);
3849                                                 goto abort_unlock;
3850                                         }
3851                                         goto done_unlock;
3852                                 }
3853                                 if (!list_empty(&mddev->disks)) {
3854                                         printk(KERN_WARNING
3855                                                "md: array %s already has disks!\n",
3856                                                mdname(mddev));
3857                                         err = -EBUSY;
3858                                         goto abort_unlock;
3859                                 }
3860                                 if (mddev->raid_disks) {
3861                                         printk(KERN_WARNING
3862                                                "md: array %s already initialised!\n",
3863                                                mdname(mddev));
3864                                         err = -EBUSY;
3865                                         goto abort_unlock;
3866                                 }
3867                                 err = set_array_info(mddev, &info);
3868                                 if (err) {
3869                                         printk(KERN_WARNING "md: couldn't set"
3870                                                " array info. %d\n", err);
3871                                         goto abort_unlock;
3872                                 }
3873                         }
3874                         goto done_unlock;
3875
3876                 default:;
3877         }
3878
3879         /*
3880          * Commands querying/configuring an existing array:
3881          */
3882         /* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
3883          * RUN_ARRAY, and SET_BITMAP_FILE are allowed */
3884         if (!mddev->raid_disks && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
3885                         && cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE) {
3886                 err = -ENODEV;
3887                 goto abort_unlock;
3888         }
3889
3890         /*
3891          * Commands even a read-only array can execute:
3892          */
3893         switch (cmd)
3894         {
3895                 case GET_ARRAY_INFO:
3896                         err = get_array_info(mddev, argp);
3897                         goto done_unlock;
3898
3899                 case GET_BITMAP_FILE:
3900                         err = get_bitmap_file(mddev, argp);
3901                         goto done_unlock;
3902
3903                 case GET_DISK_INFO:
3904                         err = get_disk_info(mddev, argp);
3905                         goto done_unlock;
3906
3907                 case RESTART_ARRAY_RW:
3908                         err = restart_array(mddev);
3909                         goto done_unlock;
3910
3911                 case STOP_ARRAY:
3912                         err = do_md_stop (mddev, 0);
3913                         goto done_unlock;
3914
3915                 case STOP_ARRAY_RO:
3916                         err = do_md_stop (mddev, 1);
3917                         goto done_unlock;
3918
3919         /*
3920          * We have a problem here : there is no easy way to give a CHS
3921          * virtual geometry. We currently pretend that we have a 2 heads
3922          * 4 sectors (with a BIG number of cylinders...). This drives
3923          * dosfs just mad... ;-)
3924          */
3925         }
3926
3927         /*
3928          * The remaining ioctls are changing the state of the
3929          * superblock, so we do not allow them on read-only arrays.
3930          * However non-MD ioctls (e.g. get-size) will still come through
3931          * here and hit the 'default' below, so only disallow
3932          * 'md' ioctls, and switch to rw mode if started auto-readonly.
3933          */
3934         if (_IOC_TYPE(cmd) == MD_MAJOR &&
3935             mddev->ro && mddev->pers) {
3936                 if (mddev->ro == 2) {
3937                         mddev->ro = 0;
3938                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3939                 md_wakeup_thread(mddev->thread);
3940
3941                 } else {
3942                         err = -EROFS;
3943                         goto abort_unlock;
3944                 }
3945         }
3946
3947         switch (cmd)
3948         {
3949                 case ADD_NEW_DISK:
3950                 {
3951                         mdu_disk_info_t info;
3952                         if (copy_from_user(&info, argp, sizeof(info)))
3953                                 err = -EFAULT;
3954                         else
3955                                 err = add_new_disk(mddev, &info);
3956                         goto done_unlock;
3957                 }
3958
3959                 case HOT_REMOVE_DISK:
3960                         err = hot_remove_disk(mddev, new_decode_dev(arg));
3961                         goto done_unlock;
3962
3963                 case HOT_ADD_DISK:
3964                         err = hot_add_disk(mddev, new_decode_dev(arg));
3965                         goto done_unlock;
3966
3967                 case SET_DISK_FAULTY:
3968                         err = set_disk_faulty(mddev, new_decode_dev(arg));
3969                         goto done_unlock;
3970
3971                 case RUN_ARRAY:
3972                         err = do_md_run (mddev);
3973                         goto done_unlock;
3974
3975                 case SET_BITMAP_FILE:
3976                         err = set_bitmap_file(mddev, (int)arg);
3977                         goto done_unlock;
3978
3979                 default:
3980                         if (_IOC_TYPE(cmd) == MD_MAJOR)
3981                                 printk(KERN_WARNING "md: %s(pid %d) used"
3982                                         " obsolete MD ioctl, upgrade your"
3983                                         " software to use new ictls.\n",
3984                                         current->comm, current->pid);
3985                         err = -EINVAL;
3986                         goto abort_unlock;
3987         }
3988
3989 done_unlock:
3990 abort_unlock:
3991         mddev_unlock(mddev);
3992
3993         return err;
3994 done:
3995         if (err)
3996                 MD_BUG();
3997 abort:
3998         return err;
3999 }
4000
4001 static int md_open(struct inode *inode, struct file *file)
4002 {
4003         /*
4004          * Succeed if we can lock the mddev, which confirms that
4005          * it isn't being stopped right now.
4006          */
4007         mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
4008         int err;
4009
4010         if ((err = mddev_lock(mddev)))
4011                 goto out;
4012
4013         err = 0;
4014         mddev_get(mddev);
4015         mddev_unlock(mddev);
4016
4017         check_disk_change(inode->i_bdev);
4018  out:
4019         return err;
4020 }
4021
4022 static int md_release(struct inode *inode, struct file * file)
4023 {
4024         mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
4025
4026         if (!mddev)
4027                 BUG();
4028         mddev_put(mddev);
4029
4030         return 0;
4031 }
4032
4033 static int md_media_changed(struct gendisk *disk)
4034 {
4035         mddev_t *mddev = disk->private_data;
4036
4037         return mddev->changed;
4038 }
4039
4040 static int md_revalidate(struct gendisk *disk)
4041 {
4042         mddev_t *mddev = disk->private_data;
4043
4044         mddev->changed = 0;
4045         return 0;
4046 }
4047 static struct block_device_operations md_fops =
4048 {
4049         .owner          = THIS_MODULE,
4050         .open           = md_open,
4051         .release        = md_release,
4052         .ioctl          = md_ioctl,
4053         .getgeo         = md_getgeo,
4054         .media_changed  = md_media_changed,
4055         .revalidate_disk= md_revalidate,
4056 };
4057
4058 static int md_thread(void * arg)
4059 {
4060         mdk_thread_t *thread = arg;
4061
4062         /*
4063          * md_thread is a 'system-thread', it's priority should be very
4064          * high. We avoid resource deadlocks individually in each
4065          * raid personality. (RAID5 does preallocation) We also use RR and
4066          * the very same RT priority as kswapd, thus we will never get
4067          * into a priority inversion deadlock.
4068          *
4069          * we definitely have to have equal or higher priority than
4070          * bdflush, otherwise bdflush will deadlock if there are too
4071          * many dirty RAID5 blocks.
4072          */
4073
4074         allow_signal(SIGKILL);
4075         while (!kthread_should_stop()) {
4076
4077                 /* We need to wait INTERRUPTIBLE so that
4078                  * we don't add to the load-average.
4079                  * That means we need to be sure no signals are
4080                  * pending
4081                  */
4082                 if (signal_pending(current))
4083                         flush_signals(current);
4084
4085                 wait_event_interruptible_timeout
4086                         (thread->wqueue,
4087                          test_bit(THREAD_WAKEUP, &thread->flags)
4088                          || kthread_should_stop(),
4089                          thread->timeout);
4090                 try_to_freeze();
4091
4092                 clear_bit(THREAD_WAKEUP, &thread->flags);
4093
4094                 thread->run(thread->mddev);
4095         }
4096
4097         return 0;
4098 }
4099
4100 void md_wakeup_thread(mdk_thread_t *thread)
4101 {
4102         if (thread) {
4103                 dprintk("md: waking up MD thread %s.\n", thread->tsk->comm);
4104                 set_bit(THREAD_WAKEUP, &thread->flags);
4105                 wake_up(&thread->wqueue);
4106         }
4107 }
4108
4109 mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev,
4110                                  const char *name)
4111 {
4112         mdk_thread_t *thread;
4113
4114         thread = kzalloc(sizeof(mdk_thread_t), GFP_KERNEL);
4115         if (!thread)
4116                 return NULL;
4117
4118         init_waitqueue_head(&thread->wqueue);
4119
4120         thread->run = run;
4121         thread->mddev = mddev;
4122         thread->timeout = MAX_SCHEDULE_TIMEOUT;
4123         thread->tsk = kthread_run(md_thread, thread, name, mdname(thread->mddev));
4124         if (IS_ERR(thread->tsk)) {
4125                 kfree(thread);
4126                 return NULL;
4127         }
4128         return thread;
4129 }
4130
4131 void md_unregister_thread(mdk_thread_t *thread)
4132 {
4133         dprintk("interrupting MD-thread pid %d\n", thread->tsk->pid);
4134
4135         kthread_stop(thread->tsk);
4136         kfree(thread);
4137 }
4138
4139 void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
4140 {
4141         if (!mddev) {
4142                 MD_BUG();
4143                 return;
4144         }
4145
4146         if (!rdev || test_bit(Faulty, &rdev->flags))
4147                 return;
4148 /*
4149         dprintk("md_error dev:%s, rdev:(%d:%d), (caller: %p,%p,%p,%p).\n",
4150                 mdname(mddev),
4151                 MAJOR(rdev->bdev->bd_dev), MINOR(rdev->bdev->bd_dev),
4152                 __builtin_return_address(0),__builtin_return_address(1),
4153                 __builtin_return_address(2),__builtin_return_address(3));
4154 */
4155         if (!mddev->pers->error_handler)
4156                 return;
4157         mddev->pers->error_handler(mddev,rdev);
4158         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
4159         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4160         md_wakeup_thread(mddev->thread);
4161         md_new_event_inintr(mddev);
4162 }
4163
4164 /* seq_file implementation /proc/mdstat */
4165
4166 static void status_unused(struct seq_file *seq)
4167 {
4168         int i = 0;
4169         mdk_rdev_t *rdev;
4170         struct list_head *tmp;
4171
4172         seq_printf(seq, "unused devices: ");
4173
4174         ITERATE_RDEV_PENDING(rdev,tmp) {
4175                 char b[BDEVNAME_SIZE];
4176                 i++;
4177                 seq_printf(seq, "%s ",
4178                               bdevname(rdev->bdev,b));
4179         }
4180         if (!i)
4181                 seq_printf(seq, "<none>");
4182
4183         seq_printf(seq, "\n");
4184 }
4185
4186
4187 static void status_resync(struct seq_file *seq, mddev_t * mddev)
4188 {
4189         sector_t max_blocks, resync, res;
4190         unsigned long dt, db, rt;
4191         int scale;
4192         unsigned int per_milli;
4193
4194         resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active))/2;
4195
4196         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
4197                 max_blocks = mddev->resync_max_sectors >> 1;
4198         else
4199                 max_blocks = mddev->size;
4200
4201         /*
4202          * Should not happen.
4203          */
4204         if (!max_blocks) {
4205                 MD_BUG();
4206                 return;
4207         }
4208         /* Pick 'scale' such that (resync>>scale)*1000 will fit
4209          * in a sector_t, and (max_blocks>>scale) will fit in a
4210          * u32, as those are the requirements for sector_div.
4211          * Thus 'scale' must be at least 10
4212          */
4213         scale = 10;
4214         if (sizeof(sector_t) > sizeof(unsigned long)) {
4215                 while ( max_blocks/2 > (1ULL<<(scale+32)))
4216                         scale++;
4217         }
4218         res = (resync>>scale)*1000;
4219         sector_div(res, (u32)((max_blocks>>scale)+1));
4220
4221         per_milli = res;
4222         {
4223                 int i, x = per_milli/50, y = 20-x;
4224                 seq_printf(seq, "[");
4225                 for (i = 0; i < x; i++)
4226                         seq_printf(seq, "=");
4227                 seq_printf(seq, ">");
4228                 for (i = 0; i < y; i++)
4229                         seq_printf(seq, ".");
4230                 seq_printf(seq, "] ");
4231         }
4232         seq_printf(seq, " %s =%3u.%u%% (%llu/%llu)",
4233                    (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)?
4234                     "reshape" :
4235                       (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
4236                        "resync" : "recovery")),
4237                       per_milli/10, per_milli % 10,
4238                    (unsigned long long) resync,
4239                    (unsigned long long) max_blocks);
4240
4241         /*
4242          * We do not want to overflow, so the order of operands and
4243          * the * 100 / 100 trick are important. We do a +1 to be
4244          * safe against division by zero. We only estimate anyway.
4245          *
4246          * dt: time from mark until now
4247          * db: blocks written from mark until now
4248          * rt: remaining time
4249          */
4250         dt = ((jiffies - mddev->resync_mark) / HZ);
4251         if (!dt) dt++;
4252         db = resync - (mddev->resync_mark_cnt/2);
4253         rt = (dt * ((unsigned long)(max_blocks-resync) / (db/100+1)))/100;
4254
4255         seq_printf(seq, " finish=%lu.%lumin", rt / 60, (rt % 60)/6);
4256
4257         seq_printf(seq, " speed=%ldK/sec", db/dt);
4258 }
4259
4260 static void *md_seq_start(struct seq_file *seq, loff_t *pos)
4261 {
4262         struct list_head *tmp;
4263         loff_t l = *pos;
4264         mddev_t *mddev;
4265
4266         if (l >= 0x10000)
4267                 return NULL;
4268         if (!l--)
4269                 /* header */
4270                 return (void*)1;
4271
4272         spin_lock(&all_mddevs_lock);
4273         list_for_each(tmp,&all_mddevs)
4274                 if (!l--) {
4275                         mddev = list_entry(tmp, mddev_t, all_mddevs);
4276                         mddev_get(mddev);
4277                         spin_unlock(&all_mddevs_lock);
4278                         return mddev;
4279                 }
4280         spin_unlock(&all_mddevs_lock);
4281         if (!l--)
4282                 return (void*)2;/* tail */
4283         return NULL;
4284 }
4285
4286 static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4287 {
4288         struct list_head *tmp;
4289         mddev_t *next_mddev, *mddev = v;
4290
4291         ++*pos;
4292         if (v == (void*)2)
4293                 return NULL;
4294
4295         spin_lock(&all_mddevs_lock);
4296         if (v == (void*)1)
4297                 tmp = all_mddevs.next;
4298         else
4299                 tmp = mddev->all_mddevs.next;
4300         if (tmp != &all_mddevs)
4301                 next_mddev = mddev_get(list_entry(tmp,mddev_t,all_mddevs));
4302         else {
4303                 next_mddev = (void*)2;
4304                 *pos = 0x10000;
4305         }
4306         spin_unlock(&all_mddevs_lock);
4307
4308         if (v != (void*)1)
4309                 mddev_put(mddev);
4310         return next_mddev;
4311
4312 }
4313
4314 static void md_seq_stop(struct seq_file *seq, void *v)
4315 {
4316         mddev_t *mddev = v;
4317
4318         if (mddev && v != (void*)1 && v != (void*)2)
4319                 mddev_put(mddev);
4320 }
4321
4322 struct mdstat_info {
4323         int event;
4324 };
4325
4326 static int md_seq_show(struct seq_file *seq, void *v)
4327 {
4328         mddev_t *mddev = v;
4329         sector_t size;
4330         struct list_head *tmp2;
4331         mdk_rdev_t *rdev;
4332         struct mdstat_info *mi = seq->private;
4333         struct bitmap *bitmap;
4334
4335         if (v == (void*)1) {
4336                 struct mdk_personality *pers;
4337                 seq_printf(seq, "Personalities : ");
4338                 spin_lock(&pers_lock);
4339                 list_for_each_entry(pers, &pers_list, list)
4340                         seq_printf(seq, "[%s] ", pers->name);
4341
4342                 spin_unlock(&pers_lock);
4343                 seq_printf(seq, "\n");
4344                 mi->event = atomic_read(&md_event_count);
4345                 return 0;
4346         }
4347         if (v == (void*)2) {
4348                 status_unused(seq);
4349                 return 0;
4350         }
4351
4352         if (mddev_lock(mddev) < 0)
4353                 return -EINTR;
4354
4355         if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
4356                 seq_printf(seq, "%s : %sactive", mdname(mddev),
4357                                                 mddev->pers ? "" : "in");
4358                 if (mddev->pers) {
4359                         if (mddev->ro==1)
4360                                 seq_printf(seq, " (read-only)");
4361                         if (mddev->ro==2)
4362                                 seq_printf(seq, "(auto-read-only)");
4363                         seq_printf(seq, " %s", mddev->pers->name);
4364                 }
4365
4366                 size = 0;
4367                 ITERATE_RDEV(mddev,rdev,tmp2) {
4368                         char b[BDEVNAME_SIZE];
4369                         seq_printf(seq, " %s[%d]",
4370                                 bdevname(rdev->bdev,b), rdev->desc_nr);
4371                         if (test_bit(WriteMostly, &rdev->flags))
4372                                 seq_printf(seq, "(W)");
4373                         if (test_bit(Faulty, &rdev->flags)) {
4374                                 seq_printf(seq, "(F)");
4375                                 continue;
4376                         } else if (rdev->raid_disk < 0)
4377                                 seq_printf(seq, "(S)"); /* spare */
4378                         size += rdev->size;
4379                 }
4380
4381                 if (!list_empty(&mddev->disks)) {
4382                         if (mddev->pers)
4383                                 seq_printf(seq, "\n      %llu blocks",
4384                                         (unsigned long long)mddev->array_size);
4385                         else
4386                                 seq_printf(seq, "\n      %llu blocks",
4387                                         (unsigned long long)size);
4388                 }
4389                 if (mddev->persistent) {
4390                         if (mddev->major_version != 0 ||
4391                             mddev->minor_version != 90) {
4392                                 seq_printf(seq," super %d.%d",
4393                                            mddev->major_version,
4394                                            mddev->minor_version);
4395                         }
4396                 } else
4397                         seq_printf(seq, " super non-persistent");
4398
4399                 if (mddev->pers) {
4400                         mddev->pers->status (seq, mddev);
4401                         seq_printf(seq, "\n      ");
4402                         if (mddev->pers->sync_request) {
4403                                 if (mddev->curr_resync > 2) {
4404                                         status_resync (seq, mddev);
4405                                         seq_printf(seq, "\n      ");
4406                                 } else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
4407                                         seq_printf(seq, "\tresync=DELAYED\n      ");
4408                                 else if (mddev->recovery_cp < MaxSector)
4409                                         seq_printf(seq, "\tresync=PENDING\n      ");
4410                         }
4411                 } else
4412                         seq_printf(seq, "\n       ");
4413
4414                 if ((bitmap = mddev->bitmap)) {
4415                         unsigned long chunk_kb;
4416                         unsigned long flags;
4417                         spin_lock_irqsave(&bitmap->lock, flags);
4418                         chunk_kb = bitmap->chunksize >> 10;
4419                         seq_printf(seq, "bitmap: %lu/%lu pages [%luKB], "
4420                                 "%lu%s chunk",
4421                                 bitmap->pages - bitmap->missing_pages,
4422                                 bitmap->pages,
4423                                 (bitmap->pages - bitmap->missing_pages)
4424                                         << (PAGE_SHIFT - 10),
4425                                 chunk_kb ? chunk_kb : bitmap->chunksize,
4426                                 chunk_kb ? "KB" : "B");
4427                         if (bitmap->file) {
4428                                 seq_printf(seq, ", file: ");
4429                                 seq_path(seq, bitmap->file->f_vfsmnt,
4430                                          bitmap->file->f_dentry," \t\n");
4431                         }
4432
4433                         seq_printf(seq, "\n");
4434                         spin_unlock_irqrestore(&bitmap->lock, flags);
4435                 }
4436
4437                 seq_printf(seq, "\n");
4438         }
4439         mddev_unlock(mddev);
4440
4441         return 0;
4442 }
4443
4444 static struct seq_operations md_seq_ops = {
4445         .start  = md_seq_start,
4446         .next   = md_seq_next,
4447         .stop   = md_seq_stop,
4448         .show   = md_seq_show,
4449 };
4450
4451 static int md_seq_open(struct inode *inode, struct file *file)
4452 {
4453         int error;
4454         struct mdstat_info *mi = kmalloc(sizeof(*mi), GFP_KERNEL);
4455         if (mi == NULL)
4456                 return -ENOMEM;
4457
4458         error = seq_open(file, &md_seq_ops);
4459         if (error)
4460                 kfree(mi);
4461         else {
4462                 struct seq_file *p = file->private_data;
4463                 p->private = mi;
4464                 mi->event = atomic_read(&md_event_count);
4465         }
4466         return error;
4467 }
4468
4469 static int md_seq_release(struct inode *inode, struct file *file)
4470 {
4471         struct seq_file *m = file->private_data;
4472         struct mdstat_info *mi = m->private;
4473         m->private = NULL;
4474         kfree(mi);
4475         return seq_release(inode, file);
4476 }
4477
4478 static unsigned int mdstat_poll(struct file *filp, poll_table *wait)
4479 {
4480         struct seq_file *m = filp->private_data;
4481         struct mdstat_info *mi = m->private;
4482         int mask;
4483
4484         poll_wait(filp, &md_event_waiters, wait);
4485
4486         /* always allow read */
4487         mask = POLLIN | POLLRDNORM;
4488
4489         if (mi->event != atomic_read(&md_event_count))
4490                 mask |= POLLERR | POLLPRI;
4491         return mask;
4492 }
4493
4494 static struct file_operations md_seq_fops = {
4495         .open           = md_seq_open,
4496         .read           = seq_read,
4497         .llseek         = seq_lseek,
4498         .release        = md_seq_release,
4499         .poll           = mdstat_poll,
4500 };
4501
4502 int register_md_personality(struct mdk_personality *p)
4503 {
4504         spin_lock(&pers_lock);
4505         list_add_tail(&p->list, &pers_list);
4506         printk(KERN_INFO "md: %s personality registered for level %d\n", p->name, p->level);
4507         spin_unlock(&pers_lock);
4508         return 0;
4509 }
4510
4511 int unregister_md_personality(struct mdk_personality *p)
4512 {
4513         printk(KERN_INFO "md: %s personality unregistered\n", p->name);
4514         spin_lock(&pers_lock);
4515         list_del_init(&p->list);
4516         spin_unlock(&pers_lock);
4517         return 0;
4518 }
4519
4520 static int is_mddev_idle(mddev_t *mddev)
4521 {
4522         mdk_rdev_t * rdev;
4523         struct list_head *tmp;
4524         int idle;
4525         unsigned long curr_events;
4526
4527         idle = 1;
4528         ITERATE_RDEV(mddev,rdev,tmp) {
4529                 struct gendisk *disk = rdev->bdev->bd_contains->bd_disk;
4530                 curr_events = disk_stat_read(disk, sectors[0]) +
4531                                 disk_stat_read(disk, sectors[1]) -
4532                                 atomic_read(&disk->sync_io);
4533                 /* The difference between curr_events and last_events
4534                  * will be affected by any new non-sync IO (making
4535                  * curr_events bigger) and any difference in the amount of
4536                  * in-flight syncio (making current_events bigger or smaller)
4537                  * The amount in-flight is currently limited to
4538                  * 32*64K in raid1/10 and 256*PAGE_SIZE in raid5/6
4539                  * which is at most 4096 sectors.
4540                  * These numbers are fairly fragile and should be made
4541                  * more robust, probably by enforcing the
4542                  * 'window size' that md_do_sync sort-of uses.
4543                  *
4544                  * Note: the following is an unsigned comparison.
4545                  */
4546                 if ((curr_events - rdev->last_events + 4096) > 8192) {
4547                         rdev->last_events = curr_events;
4548                         idle = 0;
4549                 }
4550         }
4551         return idle;
4552 }
4553
4554 void md_done_sync(mddev_t *mddev, int blocks, int ok)
4555 {
4556         /* another "blocks" (512byte) blocks have been synced */
4557         atomic_sub(blocks, &mddev->recovery_active);
4558         wake_up(&mddev->recovery_wait);
4559         if (!ok) {
4560                 set_bit(MD_RECOVERY_ERR, &mddev->recovery);
4561                 md_wakeup_thread(mddev->thread);
4562                 // stop recovery, signal do_sync ....
4563         }
4564 }
4565
4566
4567 /* md_write_start(mddev, bi)
4568  * If we need to update some array metadata (e.g. 'active' flag
4569  * in superblock) before writing, schedule a superblock update
4570  * and wait for it to complete.
4571  */
4572 void md_write_start(mddev_t *mddev, struct bio *bi)
4573 {
4574         if (bio_data_dir(bi) != WRITE)
4575                 return;
4576
4577         BUG_ON(mddev->ro == 1);
4578         if (mddev->ro == 2) {
4579                 /* need to switch to read/write */
4580                 mddev->ro = 0;
4581                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4582                 md_wakeup_thread(mddev->thread);
4583         }
4584         atomic_inc(&mddev->writes_pending);
4585         if (mddev->in_sync) {
4586                 spin_lock_irq(&mddev->write_lock);
4587                 if (mddev->in_sync) {
4588                         mddev->in_sync = 0;
4589                         mddev->sb_dirty = 1;
4590                         md_wakeup_thread(mddev->thread);
4591                 }
4592                 spin_unlock_irq(&mddev->write_lock);
4593         }
4594         wait_event(mddev->sb_wait, mddev->sb_dirty==0);
4595 }
4596
4597 void md_write_end(mddev_t *mddev)
4598 {
4599         if (atomic_dec_and_test(&mddev->writes_pending)) {
4600                 if (mddev->safemode == 2)
4601                         md_wakeup_thread(mddev->thread);
4602                 else
4603                         mod_timer(&mddev->safemode_timer, jiffies + mddev->safemode_delay);
4604         }
4605 }
4606
4607 static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
4608
4609 #define SYNC_MARKS      10
4610 #define SYNC_MARK_STEP  (3*HZ)
4611 void md_do_sync(mddev_t *mddev)
4612 {
4613         mddev_t *mddev2;
4614         unsigned int currspeed = 0,
4615                  window;
4616         sector_t max_sectors,j, io_sectors;
4617         unsigned long mark[SYNC_MARKS];
4618         sector_t mark_cnt[SYNC_MARKS];
4619         int last_mark,m;
4620         struct list_head *tmp;
4621         sector_t last_check;
4622         int skipped = 0;
4623
4624         /* just incase thread restarts... */
4625         if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
4626                 return;
4627
4628         /* we overload curr_resync somewhat here.
4629          * 0 == not engaged in resync at all
4630          * 2 == checking that there is no conflict with another sync
4631          * 1 == like 2, but have yielded to allow conflicting resync to
4632          *              commense
4633          * other == active in resync - this many blocks
4634          *
4635          * Before starting a resync we must have set curr_resync to
4636          * 2, and then checked that every "conflicting" array has curr_resync
4637          * less than ours.  When we find one that is the same or higher
4638          * we wait on resync_wait.  To avoid deadlock, we reduce curr_resync
4639          * to 1 if we choose to yield (based arbitrarily on address of mddev structure).
4640          * This will mean we have to start checking from the beginning again.
4641          *
4642          */
4643
4644         do {
4645                 mddev->curr_resync = 2;
4646
4647         try_again:
4648                 if (kthread_should_stop()) {
4649                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
4650                         goto skip;
4651                 }
4652                 ITERATE_MDDEV(mddev2,tmp) {
4653                         if (mddev2 == mddev)
4654                                 continue;
4655                         if (mddev2->curr_resync &&
4656                             match_mddev_units(mddev,mddev2)) {
4657                                 DEFINE_WAIT(wq);
4658                                 if (mddev < mddev2 && mddev->curr_resync == 2) {
4659                                         /* arbitrarily yield */
4660                                         mddev->curr_resync = 1;
4661                                         wake_up(&resync_wait);
4662                                 }
4663                                 if (mddev > mddev2 && mddev->curr_resync == 1)
4664                                         /* no need to wait here, we can wait the next
4665                                          * time 'round when curr_resync == 2
4666                                          */
4667                                         continue;
4668                                 prepare_to_wait(&resync_wait, &wq, TASK_UNINTERRUPTIBLE);
4669                                 if (!kthread_should_stop() &&
4670                                     mddev2->curr_resync >= mddev->curr_resync) {
4671                                         printk(KERN_INFO "md: delaying resync of %s"
4672                                                " until %s has finished resync (they"
4673                                                " share one or more physical units)\n",
4674                                                mdname(mddev), mdname(mddev2));
4675                                         mddev_put(mddev2);
4676                                         schedule();
4677                                         finish_wait(&resync_wait, &wq);
4678                                         goto try_again;
4679                                 }
4680                                 finish_wait(&resync_wait, &wq);
4681                         }
4682                 }
4683         } while (mddev->curr_resync < 2);
4684
4685         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
4686                 /* resync follows the size requested by the personality,
4687                  * which defaults to physical size, but can be virtual size
4688                  */
4689                 max_sectors = mddev->resync_max_sectors;
4690                 mddev->resync_mismatches = 0;
4691         } else if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
4692                 max_sectors = mddev->size << 1;
4693         else
4694                 /* recovery follows the physical size of devices */
4695                 max_sectors = mddev->size << 1;
4696
4697         printk(KERN_INFO "md: syncing RAID array %s\n", mdname(mddev));
4698         printk(KERN_INFO "md: minimum _guaranteed_ reconstruction speed:"
4699                 " %d KB/sec/disc.\n", speed_min(mddev));
4700         printk(KERN_INFO "md: using maximum available idle IO bandwidth "
4701                "(but not more than %d KB/sec) for reconstruction.\n",
4702                speed_max(mddev));
4703
4704         is_mddev_idle(mddev); /* this also initializes IO event counters */
4705         /* we don't use the checkpoint if there's a bitmap */
4706         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && !mddev->bitmap
4707             && ! test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
4708                 j = mddev->recovery_cp;
4709         else
4710                 j = 0;
4711         io_sectors = 0;
4712         for (m = 0; m < SYNC_MARKS; m++) {
4713                 mark[m] = jiffies;
4714                 mark_cnt[m] = io_sectors;
4715         }
4716         last_mark = 0;
4717         mddev->resync_mark = mark[last_mark];
4718         mddev->resync_mark_cnt = mark_cnt[last_mark];
4719
4720         /*
4721          * Tune reconstruction:
4722          */
4723         window = 32*(PAGE_SIZE/512);
4724         printk(KERN_INFO "md: using %dk window, over a total of %llu blocks.\n",
4725                 window/2,(unsigned long long) max_sectors/2);
4726
4727         atomic_set(&mddev->recovery_active, 0);
4728         init_waitqueue_head(&mddev->recovery_wait);
4729         last_check = 0;
4730
4731         if (j>2) {
4732                 printk(KERN_INFO
4733                         "md: resuming recovery of %s from checkpoint.\n",
4734                         mdname(mddev));
4735                 mddev->curr_resync = j;
4736         }
4737
4738         while (j < max_sectors) {
4739                 sector_t sectors;
4740
4741                 skipped = 0;
4742                 sectors = mddev->pers->sync_request(mddev, j, &skipped,
4743                                             currspeed < speed_min(mddev));
4744                 if (sectors == 0) {
4745                         set_bit(MD_RECOVERY_ERR, &mddev->recovery);
4746                         goto out;
4747                 }
4748
4749                 if (!skipped) { /* actual IO requested */
4750                         io_sectors += sectors;
4751                         atomic_add(sectors, &mddev->recovery_active);
4752                 }
4753
4754                 j += sectors;
4755                 if (j>1) mddev->curr_resync = j;
4756                 if (last_check == 0)
4757                         /* this is the earliers that rebuilt will be
4758                          * visible in /proc/mdstat
4759                          */
4760                         md_new_event(mddev);
4761
4762                 if (last_check + window > io_sectors || j == max_sectors)
4763                         continue;
4764
4765                 last_check = io_sectors;
4766
4767                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery) ||
4768                     test_bit(MD_RECOVERY_ERR, &mddev->recovery))
4769                         break;
4770
4771         repeat:
4772                 if (time_after_eq(jiffies, mark[last_mark] + SYNC_MARK_STEP )) {
4773                         /* step marks */
4774                         int next = (last_mark+1) % SYNC_MARKS;
4775
4776                         mddev->resync_mark = mark[next];
4777                         mddev->resync_mark_cnt = mark_cnt[next];
4778                         mark[next] = jiffies;
4779                         mark_cnt[next] = io_sectors - atomic_read(&mddev->recovery_active);
4780                         last_mark = next;
4781                 }
4782
4783
4784                 if (kthread_should_stop()) {
4785                         /*
4786                          * got a signal, exit.
4787                          */
4788                         printk(KERN_INFO
4789                                 "md: md_do_sync() got signal ... exiting\n");
4790                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
4791                         goto out;
4792                 }
4793
4794                 /*
4795                  * this loop exits only if either when we are slower than
4796                  * the 'hard' speed limit, or the system was IO-idle for
4797                  * a jiffy.
4798                  * the system might be non-idle CPU-wise, but we only care
4799                  * about not overloading the IO subsystem. (things like an
4800                  * e2fsck being done on the RAID array should execute fast)
4801                  */
4802                 mddev->queue->unplug_fn(mddev->queue);
4803                 cond_resched();
4804
4805                 currspeed = ((unsigned long)(io_sectors-mddev->resync_mark_cnt))/2
4806                         /((jiffies-mddev->resync_mark)/HZ +1) +1;
4807
4808                 if (currspeed > speed_min(mddev)) {
4809                         if ((currspeed > speed_max(mddev)) ||
4810                                         !is_mddev_idle(mddev)) {
4811                                 msleep(500);
4812                                 goto repeat;
4813                         }
4814                 }
4815         }
4816         printk(KERN_INFO "md: %s: sync done.\n",mdname(mddev));
4817         /*
4818          * this also signals 'finished resyncing' to md_stop
4819          */
4820  out:
4821         mddev->queue->unplug_fn(mddev->queue);
4822
4823         wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
4824
4825         /* tell personality that we are finished */
4826         mddev->pers->sync_request(mddev, max_sectors, &skipped, 1);
4827
4828         if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
4829             test_bit(MD_RECOVERY_SYNC, &mddev->recovery) &&
4830             !test_bit(MD_RECOVERY_CHECK, &mddev->recovery) &&
4831             mddev->curr_resync > 2 &&
4832             mddev->curr_resync >= mddev->recovery_cp) {
4833                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
4834                         printk(KERN_INFO
4835                                 "md: checkpointing recovery of %s.\n",
4836                                 mdname(mddev));
4837                         mddev->recovery_cp = mddev->curr_resync;
4838                 } else
4839                         mddev->recovery_cp = MaxSector;
4840         }
4841
4842  skip:
4843         mddev->curr_resync = 0;
4844         wake_up(&resync_wait);
4845         set_bit(MD_RECOVERY_DONE, &mddev->recovery);
4846         md_wakeup_thread(mddev->thread);
4847 }
4848 EXPORT_SYMBOL_GPL(md_do_sync);
4849
4850
4851 /*
4852  * This routine is regularly called by all per-raid-array threads to
4853  * deal with generic issues like resync and super-block update.
4854  * Raid personalities that don't have a thread (linear/raid0) do not
4855  * need this as they never do any recovery or update the superblock.
4856  *
4857  * It does not do any resync itself, but rather "forks" off other threads
4858  * to do that as needed.
4859  * When it is determined that resync is needed, we set MD_RECOVERY_RUNNING in
4860  * "->recovery" and create a thread at ->sync_thread.
4861  * When the thread finishes it sets MD_RECOVERY_DONE (and might set MD_RECOVERY_ERR)
4862  * and wakeups up this thread which will reap the thread and finish up.
4863  * This thread also removes any faulty devices (with nr_pending == 0).
4864  *
4865  * The overall approach is:
4866  *  1/ if the superblock needs updating, update it.
4867  *  2/ If a recovery thread is running, don't do anything else.
4868  *  3/ If recovery has finished, clean up, possibly marking spares active.
4869  *  4/ If there are any faulty devices, remove them.
4870  *  5/ If array is degraded, try to add spares devices
4871  *  6/ If array has spares or is not in-sync, start a resync thread.
4872  */
4873 void md_check_recovery(mddev_t *mddev)
4874 {
4875         mdk_rdev_t *rdev;
4876         struct list_head *rtmp;
4877
4878
4879         if (mddev->bitmap)
4880                 bitmap_daemon_work(mddev->bitmap);
4881
4882         if (mddev->ro)
4883                 return;
4884
4885         if (signal_pending(current)) {
4886                 if (mddev->pers->sync_request) {
4887                         printk(KERN_INFO "md: %s in immediate safe mode\n",
4888                                mdname(mddev));
4889                         mddev->safemode = 2;
4890                 }
4891                 flush_signals(current);
4892         }
4893
4894         if ( ! (
4895                 mddev->sb_dirty ||
4896                 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
4897                 test_bit(MD_RECOVERY_DONE, &mddev->recovery) ||
4898                 (mddev->safemode == 1) ||
4899                 (mddev->safemode == 2 && ! atomic_read(&mddev->writes_pending)
4900                  && !mddev->in_sync && mddev->recovery_cp == MaxSector)
4901                 ))
4902                 return;
4903
4904         if (mddev_trylock(mddev)) {
4905                 int spares =0;
4906
4907                 spin_lock_irq(&mddev->write_lock);
4908                 if (mddev->safemode && !atomic_read(&mddev->writes_pending) &&
4909                     !mddev->in_sync && mddev->recovery_cp == MaxSector) {
4910                         mddev->in_sync = 1;
4911                         mddev->sb_dirty = 1;
4912                 }
4913                 if (mddev->safemode == 1)
4914                         mddev->safemode = 0;
4915                 spin_unlock_irq(&mddev->write_lock);
4916
4917                 if (mddev->sb_dirty)
4918                         md_update_sb(mddev);
4919
4920
4921                 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
4922                     !test_bit(MD_RECOVERY_DONE, &mddev->recovery)) {
4923                         /* resync/recovery still happening */
4924                         clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4925                         goto unlock;
4926                 }
4927                 if (mddev->sync_thread) {
4928                         /* resync has finished, collect result */
4929                         md_unregister_thread(mddev->sync_thread);
4930                         mddev->sync_thread = NULL;
4931                         if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
4932                             !test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
4933                                 /* success...*/
4934                                 /* activate any spares */
4935                                 mddev->pers->spare_active(mddev);
4936                         }
4937                         md_update_sb(mddev);
4938
4939                         /* if array is no-longer degraded, then any saved_raid_disk
4940                          * information must be scrapped
4941                          */
4942                         if (!mddev->degraded)
4943                                 ITERATE_RDEV(mddev,rdev,rtmp)
4944                                         rdev->saved_raid_disk = -1;
4945
4946                         mddev->recovery = 0;
4947                         /* flag recovery needed just to double check */
4948                         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4949                         md_new_event(mddev);
4950                         goto unlock;
4951                 }
4952                 /* Clear some bits that don't mean anything, but
4953                  * might be left set
4954                  */
4955                 clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4956                 clear_bit(MD_RECOVERY_ERR, &mddev->recovery);
4957                 clear_bit(MD_RECOVERY_INTR, &mddev->recovery);
4958                 clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
4959
4960                 /* no recovery is running.
4961                  * remove any failed drives, then
4962                  * add spares if possible.
4963                  * Spare are also removed and re-added, to allow
4964                  * the personality to fail the re-add.
4965                  */
4966                 ITERATE_RDEV(mddev,rdev,rtmp)
4967                         if (rdev->raid_disk >= 0 &&
4968                             (test_bit(Faulty, &rdev->flags) || ! test_bit(In_sync, &rdev->flags)) &&
4969                             atomic_read(&rdev->nr_pending)==0) {
4970                                 if (mddev->pers->hot_remove_disk(mddev, rdev->raid_disk)==0) {
4971                                         char nm[20];
4972                                         sprintf(nm,"rd%d", rdev->raid_disk);
4973                                         sysfs_remove_link(&mddev->kobj, nm);
4974                                         rdev->raid_disk = -1;
4975                                 }
4976                         }
4977
4978                 if (mddev->degraded) {
4979                         ITERATE_RDEV(mddev,rdev,rtmp)
4980                                 if (rdev->raid_disk < 0
4981                                     && !test_bit(Faulty, &rdev->flags)) {
4982                                         if (mddev->pers->hot_add_disk(mddev,rdev)) {
4983                                                 char nm[20];
4984                                                 sprintf(nm, "rd%d", rdev->raid_disk);
4985                                                 sysfs_create_link(&mddev->kobj, &rdev->kobj, nm);
4986                                                 spares++;
4987                                                 md_new_event(mddev);
4988                                         } else
4989                                                 break;
4990                                 }
4991                 }
4992
4993                 if (spares) {
4994                         clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
4995                         clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
4996                 } else if (mddev->recovery_cp < MaxSector) {
4997                         set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
4998                 } else if (!test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
4999                         /* nothing to be done ... */
5000                         goto unlock;
5001
5002                 if (mddev->pers->sync_request) {
5003                         set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
5004                         if (spares && mddev->bitmap && ! mddev->bitmap->file) {
5005                                 /* We are adding a device or devices to an array
5006                                  * which has the bitmap stored on all devices.
5007                                  * So make sure all bitmap pages get written
5008                                  */
5009                                 bitmap_write_all(mddev->bitmap);
5010                         }
5011                         mddev->sync_thread = md_register_thread(md_do_sync,
5012                                                                 mddev,
5013                                                                 "%s_resync");
5014                         if (!mddev->sync_thread) {
5015                                 printk(KERN_ERR "%s: could not start resync"
5016                                         " thread...\n",
5017                                         mdname(mddev));
5018                                 /* leave the spares where they are, it shouldn't hurt */
5019                                 mddev->recovery = 0;
5020                         } else
5021                                 md_wakeup_thread(mddev->sync_thread);
5022                         md_new_event(mddev);
5023                 }
5024         unlock:
5025                 mddev_unlock(mddev);
5026         }
5027 }
5028
5029 static int md_notify_reboot(struct notifier_block *this,
5030                             unsigned long code, void *x)
5031 {
5032         struct list_head *tmp;
5033         mddev_t *mddev;
5034
5035         if ((code == SYS_DOWN) || (code == SYS_HALT) || (code == SYS_POWER_OFF)) {
5036
5037                 printk(KERN_INFO "md: stopping all md devices.\n");
5038
5039                 ITERATE_MDDEV(mddev,tmp)
5040                         if (mddev_trylock(mddev)) {
5041                                 do_md_stop (mddev, 1);
5042                                 mddev_unlock(mddev);
5043                         }
5044                 /*
5045                  * certain more exotic SCSI devices are known to be
5046                  * volatile wrt too early system reboots. While the
5047                  * right place to handle this issue is the given
5048                  * driver, we do want to have a safe RAID driver ...
5049                  */
5050                 mdelay(1000*1);
5051         }
5052         return NOTIFY_DONE;
5053 }
5054
5055 static struct notifier_block md_notifier = {
5056         .notifier_call  = md_notify_reboot,
5057         .next           = NULL,
5058         .priority       = INT_MAX, /* before any real devices */
5059 };
5060
5061 static void md_geninit(void)
5062 {
5063         struct proc_dir_entry *p;
5064
5065         dprintk("md: sizeof(mdp_super_t) = %d\n", (int)sizeof(mdp_super_t));
5066
5067         p = create_proc_entry("mdstat", S_IRUGO, NULL);
5068         if (p)
5069                 p->proc_fops = &md_seq_fops;
5070 }
5071
5072 static int __init md_init(void)
5073 {
5074         int minor;
5075
5076         printk(KERN_INFO "md: md driver %d.%d.%d MAX_MD_DEVS=%d,"
5077                         " MD_SB_DISKS=%d\n",
5078                         MD_MAJOR_VERSION, MD_MINOR_VERSION,
5079                         MD_PATCHLEVEL_VERSION, MAX_MD_DEVS, MD_SB_DISKS);
5080         printk(KERN_INFO "md: bitmap version %d.%d\n", BITMAP_MAJOR_HI,
5081                         BITMAP_MINOR);
5082
5083         if (register_blkdev(MAJOR_NR, "md"))
5084                 return -1;
5085         if ((mdp_major=register_blkdev(0, "mdp"))<=0) {
5086                 unregister_blkdev(MAJOR_NR, "md");
5087                 return -1;
5088         }
5089         devfs_mk_dir("md");
5090         blk_register_region(MKDEV(MAJOR_NR, 0), MAX_MD_DEVS, THIS_MODULE,
5091                                 md_probe, NULL, NULL);
5092         blk_register_region(MKDEV(mdp_major, 0), MAX_MD_DEVS<<MdpMinorShift, THIS_MODULE,
5093                             md_probe, NULL, NULL);
5094
5095         for (minor=0; minor < MAX_MD_DEVS; ++minor)
5096                 devfs_mk_bdev(MKDEV(MAJOR_NR, minor),
5097                                 S_IFBLK|S_IRUSR|S_IWUSR,
5098                                 "md/%d", minor);
5099
5100         for (minor=0; minor < MAX_MD_DEVS; ++minor)
5101                 devfs_mk_bdev(MKDEV(mdp_major, minor<<MdpMinorShift),
5102                               S_IFBLK|S_IRUSR|S_IWUSR,
5103                               "md/mdp%d", minor);
5104
5105
5106         register_reboot_notifier(&md_notifier);
5107         raid_table_header = register_sysctl_table(raid_root_table, 1);
5108
5109         md_geninit();
5110         return (0);
5111 }
5112
5113
5114 #ifndef MODULE
5115
5116 /*
5117  * Searches all registered partitions for autorun RAID arrays
5118  * at boot time.
5119  */
5120 static dev_t detected_devices[128];
5121 static int dev_cnt;
5122
5123 void md_autodetect_dev(dev_t dev)
5124 {
5125         if (dev_cnt >= 0 && dev_cnt < 127)
5126                 detected_devices[dev_cnt++] = dev;
5127 }
5128
5129
5130 static void autostart_arrays(int part)
5131 {
5132         mdk_rdev_t *rdev;
5133         int i;
5134
5135         printk(KERN_INFO "md: Autodetecting RAID arrays.\n");
5136
5137         for (i = 0; i < dev_cnt; i++) {
5138                 dev_t dev = detected_devices[i];
5139
5140                 rdev = md_import_device(dev,0, 0);
5141                 if (IS_ERR(rdev))
5142                         continue;
5143
5144                 if (test_bit(Faulty, &rdev->flags)) {
5145                         MD_BUG();
5146                         continue;
5147                 }
5148                 list_add(&rdev->same_set, &pending_raid_disks);
5149         }
5150         dev_cnt = 0;
5151
5152         autorun_devices(part);
5153 }
5154
5155 #endif
5156
5157 static __exit void md_exit(void)
5158 {
5159         mddev_t *mddev;
5160         struct list_head *tmp;
5161         int i;
5162         blk_unregister_region(MKDEV(MAJOR_NR,0), MAX_MD_DEVS);
5163         blk_unregister_region(MKDEV(mdp_major,0), MAX_MD_DEVS << MdpMinorShift);
5164         for (i=0; i < MAX_MD_DEVS; i++)
5165                 devfs_remove("md/%d", i);
5166         for (i=0; i < MAX_MD_DEVS; i++)
5167                 devfs_remove("md/d%d", i);
5168
5169         devfs_remove("md");
5170
5171         unregister_blkdev(MAJOR_NR,"md");
5172         unregister_blkdev(mdp_major, "mdp");
5173         unregister_reboot_notifier(&md_notifier);
5174         unregister_sysctl_table(raid_table_header);
5175         remove_proc_entry("mdstat", NULL);
5176         ITERATE_MDDEV(mddev,tmp) {
5177                 struct gendisk *disk = mddev->gendisk;
5178                 if (!disk)
5179                         continue;
5180                 export_array(mddev);
5181                 del_gendisk(disk);
5182                 put_disk(disk);
5183                 mddev->gendisk = NULL;
5184                 mddev_put(mddev);
5185         }
5186 }
5187
5188 module_init(md_init)
5189 module_exit(md_exit)
5190
5191 static int get_ro(char *buffer, struct kernel_param *kp)
5192 {
5193         return sprintf(buffer, "%d", start_readonly);
5194 }
5195 static int set_ro(const char *val, struct kernel_param *kp)
5196 {
5197         char *e;
5198         int num = simple_strtoul(val, &e, 10);
5199         if (*val && (*e == '\0' || *e == '\n')) {
5200                 start_readonly = num;
5201                 return 0;
5202         }
5203         return -EINVAL;
5204 }
5205
5206 module_param_call(start_ro, set_ro, get_ro, NULL, 0600);
5207 module_param(start_dirty_degraded, int, 0644);
5208
5209
5210 EXPORT_SYMBOL(register_md_personality);
5211 EXPORT_SYMBOL(unregister_md_personality);
5212 EXPORT_SYMBOL(md_error);
5213 EXPORT_SYMBOL(md_done_sync);
5214 EXPORT_SYMBOL(md_write_start);
5215 EXPORT_SYMBOL(md_write_end);
5216 EXPORT_SYMBOL(md_register_thread);
5217 EXPORT_SYMBOL(md_unregister_thread);
5218 EXPORT_SYMBOL(md_wakeup_thread);
5219 EXPORT_SYMBOL(md_print_devices);
5220 EXPORT_SYMBOL(md_check_recovery);
5221 MODULE_LICENSE("GPL");
5222 MODULE_ALIAS("md");
5223 MODULE_ALIAS_BLOCKDEV_MAJOR(MD_MAJOR);