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