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/kernel.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/buffer_head.h> /* for invalidate_bdev */
  43 #include <linux/poll.h>
  44 #include <linux/mutex.h>
  45 #include <linux/ctype.h>
  46 #include <linux/freezer.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 static void md_print_devices(void);
  76
  77 #define MD_BUG(x...) { printk("md: bug in file %s, line %d\n", __FILE__, __LINE__); md_print_devices(); }
  78
  79 /*
  80  * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
  81  * is 1000 KB/sec, so the extra system load does not show up that much.
  82  * Increase it if you want to have more _guaranteed_ speed. Note that
  83  * the RAID driver will use the maximum available bandwidth if the IO
  84  * subsystem is idle. There is also an 'absolute maximum' reconstruction
  85  * speed limit - in case reconstruction slows down your system despite
  86  * idle IO detection.
  87  *
  88  * you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
  89  * or /sys/block/mdX/md/sync_speed_{min,max}
  90  */
  91
  92 static int sysctl_speed_limit_min = 1000;
  93 static int sysctl_speed_limit_max = 200000;
  94 static inline int speed_min(mddev_t *mddev)
  95 {
  96         return mddev->sync_speed_min ?
  97                 mddev->sync_speed_min : sysctl_speed_limit_min;
  98 }
  99
 100 static inline int speed_max(mddev_t *mddev)
 101 {
 102         return mddev->sync_speed_max ?
 103                 mddev->sync_speed_max : sysctl_speed_limit_max;
 104 }
 105
 106 static struct ctl_table_header *raid_table_header;
 107
 108 static ctl_table raid_table[] = {
 109         {
 110                 .ctl_name       = DEV_RAID_SPEED_LIMIT_MIN,
 111                 .procname       = "speed_limit_min",
 112                 .data           = &sysctl_speed_limit_min,
 113                 .maxlen         = sizeof(int),
 114                 .mode           = S_IRUGO|S_IWUSR,
 115                 .proc_handler   = &proc_dointvec,
 116         },
 117         {
 118                 .ctl_name       = DEV_RAID_SPEED_LIMIT_MAX,
 119                 .procname       = "speed_limit_max",
 120                 .data           = &sysctl_speed_limit_max,
 121                 .maxlen         = sizeof(int),
 122                 .mode           = S_IRUGO|S_IWUSR,
 123                 .proc_handler   = &proc_dointvec,
 124         },
 125         { .ctl_name = 0 }
 126 };
 127
 128 static ctl_table raid_dir_table[] = {
 129         {
 130                 .ctl_name       = DEV_RAID,
 131                 .procname       = "raid",
 132                 .maxlen         = 0,
 133                 .mode           = S_IRUGO|S_IXUGO,
 134                 .child          = raid_table,
 135         },
 136         { .ctl_name = 0 }
 137 };
 138
 139 static ctl_table raid_root_table[] = {
 140         {
 141                 .ctl_name       = CTL_DEV,
 142                 .procname       = "dev",
 143                 .maxlen         = 0,
 144                 .mode           = 0555,
 145                 .child          = raid_dir_table,
 146         },
 147         { .ctl_name = 0 }
 148 };
 149
 150 static struct block_device_operations md_fops;
 151
 152 static int start_readonly;
 153
 154 /*
 155  * We have a system wide 'event count' that is incremented
 156  * on any 'interesting' event, and readers of /proc/mdstat
 157  * can use 'poll' or 'select' to find out when the event
 158  * count increases.
 159  *
 160  * Events are:
 161  *  start array, stop array, error, add device, remove device,
 162  *  start build, activate spare
 163  */
 164 static DECLARE_WAIT_QUEUE_HEAD(md_event_waiters);
 165 static atomic_t md_event_count;
 166 void md_new_event(mddev_t *mddev)
 167 {
 168         atomic_inc(&md_event_count);
 169         wake_up(&md_event_waiters);
 170         sysfs_notify(&mddev->kobj, NULL, "sync_action");
 171 }
 172 EXPORT_SYMBOL_GPL(md_new_event);
 173
 174 /* Alternate version that can be called from interrupts
 175  * when calling sysfs_notify isn't needed.
 176  */
 177 static void md_new_event_inintr(mddev_t *mddev)
 178 {
 179         atomic_inc(&md_event_count);
 180         wake_up(&md_event_waiters);
 181 }
 182
 183 /*
 184  * Enables to iterate over all existing md arrays
 185  * all_mddevs_lock protects this list.
 186  */
 187 static LIST_HEAD(all_mddevs);
 188 static DEFINE_SPINLOCK(all_mddevs_lock);
 189
 190
 191 /*
 192  * iterates through all used mddevs in the system.
 193  * We take care to grab the all_mddevs_lock whenever navigating
 194  * the list, and to always hold a refcount when unlocked.
 195  * Any code which breaks out of this loop while own
 196  * a reference to the current mddev and must mddev_put it.
 197  */
 198 #define for_each_mddev(mddev,tmp)                                       \
 199                                                                         \
 200         for (({ spin_lock(&all_mddevs_lock);                            \
 201                 tmp = all_mddevs.next;                                  \
 202                 mddev = NULL;});                                        \
 203              ({ if (tmp != &all_mddevs)                                 \
 204                         mddev_get(list_entry(tmp, mddev_t, all_mddevs));\
 205                 spin_unlock(&all_mddevs_lock);                          \
 206                 if (mddev) mddev_put(mddev);                            \
 207                 mddev = list_entry(tmp, mddev_t, all_mddevs);           \
 208                 tmp != &all_mddevs;});                                  \
 209              ({ spin_lock(&all_mddevs_lock);                            \
 210                 tmp = tmp->next;})                                      \
 211                 )
 212
 213
 214 static int md_fail_request (struct request_queue *q, struct bio *bio)
 215 {
 216         bio_io_error(bio);
 217         return 0;
 218 }
 219
 220 static inline mddev_t *mddev_get(mddev_t *mddev)
 221 {
 222         atomic_inc(&mddev->active);
 223         return mddev;
 224 }
 225
 226 static void mddev_put(mddev_t *mddev)
 227 {
 228         if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
 229                 return;
 230         if (!mddev->raid_disks && list_empty(&mddev->disks)) {
 231                 list_del(&mddev->all_mddevs);
 232                 spin_unlock(&all_mddevs_lock);
 233                 blk_cleanup_queue(mddev->queue);
 234                 kobject_put(&mddev->kobj);
 235         } else
 236                 spin_unlock(&all_mddevs_lock);
 237 }
 238
 239 static mddev_t * mddev_find(dev_t unit)
 240 {
 241         mddev_t *mddev, *new = NULL;
 242
 243  retry:
 244         spin_lock(&all_mddevs_lock);
 245         list_for_each_entry(mddev, &all_mddevs, all_mddevs)
 246                 if (mddev->unit == unit) {
 247                         mddev_get(mddev);
 248                         spin_unlock(&all_mddevs_lock);
 249                         kfree(new);
 250                         return mddev;
 251                 }
 252
 253         if (new) {
 254                 list_add(&new->all_mddevs, &all_mddevs);
 255                 spin_unlock(&all_mddevs_lock);
 256                 return new;
 257         }
 258         spin_unlock(&all_mddevs_lock);
 259
 260         new = kzalloc(sizeof(*new), GFP_KERNEL);
 261         if (!new)
 262                 return NULL;
 263
 264         new->unit = unit;
 265         if (MAJOR(unit) == MD_MAJOR)
 266                 new->md_minor = MINOR(unit);
 267         else
 268                 new->md_minor = MINOR(unit) >> MdpMinorShift;
 269
 270         mutex_init(&new->reconfig_mutex);
 271         INIT_LIST_HEAD(&new->disks);
 272         INIT_LIST_HEAD(&new->all_mddevs);
 273         init_timer(&new->safemode_timer);
 274         atomic_set(&new->active, 1);
 275         spin_lock_init(&new->write_lock);
 276         init_waitqueue_head(&new->sb_wait);
 277         new->reshape_position = MaxSector;
 278         new->resync_max = MaxSector;
 279
 280         new->queue = blk_alloc_queue(GFP_KERNEL);
 281         if (!new->queue) {
 282                 kfree(new);
 283                 return NULL;
 284         }
 285         set_bit(QUEUE_FLAG_CLUSTER, &new->queue->queue_flags);
 286
 287         blk_queue_make_request(new->queue, md_fail_request);
 288
 289         goto retry;
 290 }
 291
 292 static inline int mddev_lock(mddev_t * mddev)
 293 {
 294         return mutex_lock_interruptible(&mddev->reconfig_mutex);
 295 }
 296
 297 static inline int mddev_trylock(mddev_t * mddev)
 298 {
 299         return mutex_trylock(&mddev->reconfig_mutex);
 300 }
 301
 302 static inline void mddev_unlock(mddev_t * mddev)
 303 {
 304         mutex_unlock(&mddev->reconfig_mutex);
 305
 306         md_wakeup_thread(mddev->thread);
 307 }
 308
 309 static mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr)
 310 {
 311         mdk_rdev_t * rdev;
 312         struct list_head *tmp;
 313
 314         rdev_for_each(rdev, tmp, mddev) {
 315                 if (rdev->desc_nr == nr)
 316                         return rdev;
 317         }
 318         return NULL;
 319 }
 320
 321 static mdk_rdev_t * find_rdev(mddev_t * mddev, dev_t dev)
 322 {
 323         struct list_head *tmp;
 324         mdk_rdev_t *rdev;
 325
 326         rdev_for_each(rdev, tmp, mddev) {
 327                 if (rdev->bdev->bd_dev == dev)
 328                         return rdev;
 329         }
 330         return NULL;
 331 }
 332
 333 static struct mdk_personality *find_pers(int level, char *clevel)
 334 {
 335         struct mdk_personality *pers;
 336         list_for_each_entry(pers, &pers_list, list) {
 337                 if (level != LEVEL_NONE && pers->level == level)
 338                         return pers;
 339                 if (strcmp(pers->name, clevel)==0)
 340                         return pers;
 341         }
 342         return NULL;
 343 }
 344
 345 static inline sector_t calc_dev_sboffset(struct block_device *bdev)
 346 {
 347         sector_t size = bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
 348         return MD_NEW_SIZE_BLOCKS(size);
 349 }
 350
 351 static sector_t calc_dev_size(mdk_rdev_t *rdev, unsigned chunk_size)
 352 {
 353         sector_t size;
 354
 355         size = rdev->sb_offset;
 356
 357         if (chunk_size)
 358                 size &= ~((sector_t)chunk_size/1024 - 1);
 359         return size;
 360 }
 361
 362 static int alloc_disk_sb(mdk_rdev_t * rdev)
 363 {
 364         if (rdev->sb_page)
 365                 MD_BUG();
 366
 367         rdev->sb_page = alloc_page(GFP_KERNEL);
 368         if (!rdev->sb_page) {
 369                 printk(KERN_ALERT "md: out of memory.\n");
 370                 return -EINVAL;
 371         }
 372
 373         return 0;
 374 }
 375
 376 static void free_disk_sb(mdk_rdev_t * rdev)
 377 {
 378         if (rdev->sb_page) {
 379                 put_page(rdev->sb_page);
 380                 rdev->sb_loaded = 0;
 381                 rdev->sb_page = NULL;
 382                 rdev->sb_offset = 0;
 383                 rdev->size = 0;
 384         }
 385 }
 386
 387
 388 static void super_written(struct bio *bio, int error)
 389 {
 390         mdk_rdev_t *rdev = bio->bi_private;
 391         mddev_t *mddev = rdev->mddev;
 392
 393         if (error || !test_bit(BIO_UPTODATE, &bio->bi_flags)) {
 394                 printk("md: super_written gets error=%d, uptodate=%d\n",
 395                        error, test_bit(BIO_UPTODATE, &bio->bi_flags));
 396                 WARN_ON(test_bit(BIO_UPTODATE, &bio->bi_flags));
 397                 md_error(mddev, rdev);
 398         }
 399
 400         if (atomic_dec_and_test(&mddev->pending_writes))
 401                 wake_up(&mddev->sb_wait);
 402         bio_put(bio);
 403 }
 404
 405 static void super_written_barrier(struct bio *bio, int error)
 406 {
 407         struct bio *bio2 = bio->bi_private;
 408         mdk_rdev_t *rdev = bio2->bi_private;
 409         mddev_t *mddev = rdev->mddev;
 410
 411         if (!test_bit(BIO_UPTODATE, &bio->bi_flags) &&
 412             error == -EOPNOTSUPP) {
 413                 unsigned long flags;
 414                 /* barriers don't appear to be supported :-( */
 415                 set_bit(BarriersNotsupp, &rdev->flags);
 416                 mddev->barriers_work = 0;
 417                 spin_lock_irqsave(&mddev->write_lock, flags);
 418                 bio2->bi_next = mddev->biolist;
 419                 mddev->biolist = bio2;
 420                 spin_unlock_irqrestore(&mddev->write_lock, flags);
 421                 wake_up(&mddev->sb_wait);
 422                 bio_put(bio);
 423         } else {
 424                 bio_put(bio2);
 425                 bio->bi_private = rdev;
 426                 super_written(bio, error);
 427         }
 428 }
 429
 430 void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev,
 431                    sector_t sector, int size, struct page *page)
 432 {
 433         /* write first size bytes of page to sector of rdev
 434          * Increment mddev->pending_writes before returning
 435          * and decrement it on completion, waking up sb_wait
 436          * if zero is reached.
 437          * If an error occurred, call md_error
 438          *
 439          * As we might need to resubmit the request if BIO_RW_BARRIER
 440          * causes ENOTSUPP, we allocate a spare bio...
 441          */
 442         struct bio *bio = bio_alloc(GFP_NOIO, 1);
 443         int rw = (1<<BIO_RW) | (1<<BIO_RW_SYNC);
 444
 445         bio->bi_bdev = rdev->bdev;
 446         bio->bi_sector = sector;
 447         bio_add_page(bio, page, size, 0);
 448         bio->bi_private = rdev;
 449         bio->bi_end_io = super_written;
 450         bio->bi_rw = rw;
 451
 452         atomic_inc(&mddev->pending_writes);
 453         if (!test_bit(BarriersNotsupp, &rdev->flags)) {
 454                 struct bio *rbio;
 455                 rw |= (1<<BIO_RW_BARRIER);
 456                 rbio = bio_clone(bio, GFP_NOIO);
 457                 rbio->bi_private = bio;
 458                 rbio->bi_end_io = super_written_barrier;
 459                 submit_bio(rw, rbio);
 460         } else
 461                 submit_bio(rw, bio);
 462 }
 463
 464 void md_super_wait(mddev_t *mddev)
 465 {
 466         /* wait for all superblock writes that were scheduled to complete.
 467          * if any had to be retried (due to BARRIER problems), retry them
 468          */
 469         DEFINE_WAIT(wq);
 470         for(;;) {
 471                 prepare_to_wait(&mddev->sb_wait, &wq, TASK_UNINTERRUPTIBLE);
 472                 if (atomic_read(&mddev->pending_writes)==0)
 473                         break;
 474                 while (mddev->biolist) {
 475                         struct bio *bio;
 476                         spin_lock_irq(&mddev->write_lock);
 477                         bio = mddev->biolist;
 478                         mddev->biolist = bio->bi_next ;
 479                         bio->bi_next = NULL;
 480                         spin_unlock_irq(&mddev->write_lock);
 481                         submit_bio(bio->bi_rw, bio);
 482                 }
 483                 schedule();
 484         }
 485         finish_wait(&mddev->sb_wait, &wq);
 486 }
 487
 488 static void bi_complete(struct bio *bio, int error)
 489 {
 490         complete((struct completion*)bio->bi_private);
 491 }
 492
 493 int sync_page_io(struct block_device *bdev, sector_t sector, int size,
 494                    struct page *page, int rw)
 495 {
 496         struct bio *bio = bio_alloc(GFP_NOIO, 1);
 497         struct completion event;
 498         int ret;
 499
 500         rw |= (1 << BIO_RW_SYNC);
 501
 502         bio->bi_bdev = bdev;
 503         bio->bi_sector = sector;
 504         bio_add_page(bio, page, size, 0);
 505         init_completion(&event);
 506         bio->bi_private = &event;
 507         bio->bi_end_io = bi_complete;
 508         submit_bio(rw, bio);
 509         wait_for_completion(&event);
 510
 511         ret = test_bit(BIO_UPTODATE, &bio->bi_flags);
 512         bio_put(bio);
 513         return ret;
 514 }
 515 EXPORT_SYMBOL_GPL(sync_page_io);
 516
 517 static int read_disk_sb(mdk_rdev_t * rdev, int size)
 518 {
 519         char b[BDEVNAME_SIZE];
 520         if (!rdev->sb_page) {
 521                 MD_BUG();
 522                 return -EINVAL;
 523         }
 524         if (rdev->sb_loaded)
 525                 return 0;
 526
 527
 528         if (!sync_page_io(rdev->bdev, rdev->sb_offset<<1, size, rdev->sb_page, READ))
 529                 goto fail;
 530         rdev->sb_loaded = 1;
 531         return 0;
 532
 533 fail:
 534         printk(KERN_WARNING "md: disabled device %s, could not read superblock.\n",
 535                 bdevname(rdev->bdev,b));
 536         return -EINVAL;
 537 }
 538
 539 static int uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 540 {
 541         if (    (sb1->set_uuid0 == sb2->set_uuid0) &&
 542                 (sb1->set_uuid1 == sb2->set_uuid1) &&
 543                 (sb1->set_uuid2 == sb2->set_uuid2) &&
 544                 (sb1->set_uuid3 == sb2->set_uuid3))
 545
 546                 return 1;
 547
 548         return 0;
 549 }
 550
 551
 552 static int sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 553 {
 554         int ret;
 555         mdp_super_t *tmp1, *tmp2;
 556
 557         tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
 558         tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
 559
 560         if (!tmp1 || !tmp2) {
 561                 ret = 0;
 562                 printk(KERN_INFO "md.c: sb1 is not equal to sb2!\n");
 563                 goto abort;
 564         }
 565
 566         *tmp1 = *sb1;
 567         *tmp2 = *sb2;
 568
 569         /*
 570          * nr_disks is not constant
 571          */
 572         tmp1->nr_disks = 0;
 573         tmp2->nr_disks = 0;
 574
 575         if (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4))
 576                 ret = 0;
 577         else
 578                 ret = 1;
 579
 580 abort:
 581         kfree(tmp1);
 582         kfree(tmp2);
 583         return ret;
 584 }
 585
 586
 587 static u32 md_csum_fold(u32 csum)
 588 {
 589         csum = (csum & 0xffff) + (csum >> 16);
 590         return (csum & 0xffff) + (csum >> 16);
 591 }
 592
 593 static unsigned int calc_sb_csum(mdp_super_t * sb)
 594 {
 595         u64 newcsum = 0;
 596         u32 *sb32 = (u32*)sb;
 597         int i;
 598         unsigned int disk_csum, csum;
 599
 600         disk_csum = sb->sb_csum;
 601         sb->sb_csum = 0;
 602
 603         for (i = 0; i < MD_SB_BYTES/4 ; i++)
 604                 newcsum += sb32[i];
 605         csum = (newcsum & 0xffffffff) + (newcsum>>32);
 606
 607
 608 #ifdef CONFIG_ALPHA
 609         /* This used to use csum_partial, which was wrong for several
 610          * reasons including that different results are returned on
 611          * different architectures.  It isn't critical that we get exactly
 612          * the same return value as before (we always csum_fold before
 613          * testing, and that removes any differences).  However as we
 614          * know that csum_partial always returned a 16bit value on
 615          * alphas, do a fold to maximise conformity to previous behaviour.
 616          */
 617         sb->sb_csum = md_csum_fold(disk_csum);
 618 #else
 619         sb->sb_csum = disk_csum;
 620 #endif
 621         return csum;
 622 }
 623
 624
 625 /*
 626  * Handle superblock details.
 627  * We want to be able to handle multiple superblock formats
 628  * so we have a common interface to them all, and an array of
 629  * different handlers.
 630  * We rely on user-space to write the initial superblock, and support
 631  * reading and updating of superblocks.
 632  * Interface methods are:
 633  *   int load_super(mdk_rdev_t *dev, mdk_rdev_t *refdev, int minor_version)
 634  *      loads and validates a superblock on dev.
 635  *      if refdev != NULL, compare superblocks on both devices
 636  *    Return:
 637  *      0 - dev has a superblock that is compatible with refdev
 638  *      1 - dev has a superblock that is compatible and newer than refdev
 639  *          so dev should be used as the refdev in future
 640  *     -EINVAL superblock incompatible or invalid
 641  *     -othererror e.g. -EIO
 642  *
 643  *   int validate_super(mddev_t *mddev, mdk_rdev_t *dev)
 644  *      Verify that dev is acceptable into mddev.
 645  *       The first time, mddev->raid_disks will be 0, and data from
 646  *       dev should be merged in.  Subsequent calls check that dev
 647  *       is new enough.  Return 0 or -EINVAL
 648  *
 649  *   void sync_super(mddev_t *mddev, mdk_rdev_t *dev)
 650  *     Update the superblock for rdev with data in mddev
 651  *     This does not write to disc.
 652  *
 653  */
 654
 655 struct super_type  {
 656         char            *name;
 657         struct module   *owner;
 658         int             (*load_super)(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version);
 659         int             (*validate_super)(mddev_t *mddev, mdk_rdev_t *rdev);
 660         void            (*sync_super)(mddev_t *mddev, mdk_rdev_t *rdev);
 661 };
 662
 663 /*
 664  * load_super for 0.90.0
 665  */
 666 static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
 667 {
 668         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
 669         mdp_super_t *sb;
 670         int ret;
 671         sector_t sb_offset;
 672
 673         /*
 674          * Calculate the position of the superblock,
 675          * it's at the end of the disk.
 676          *
 677          * It also happens to be a multiple of 4Kb.
 678          */
 679         sb_offset = calc_dev_sboffset(rdev->bdev);
 680         rdev->sb_offset = sb_offset;
 681
 682         ret = read_disk_sb(rdev, MD_SB_BYTES);
 683         if (ret) return ret;
 684
 685         ret = -EINVAL;
 686
 687         bdevname(rdev->bdev, b);
 688         sb = (mdp_super_t*)page_address(rdev->sb_page);
 689
 690         if (sb->md_magic != MD_SB_MAGIC) {
 691                 printk(KERN_ERR "md: invalid raid superblock magic on %s\n",
 692                        b);
 693                 goto abort;
 694         }
 695
 696         if (sb->major_version != 0 ||
 697             sb->minor_version < 90 ||
 698             sb->minor_version > 91) {
 699                 printk(KERN_WARNING "Bad version number %d.%d on %s\n",
 700                         sb->major_version, sb->minor_version,
 701                         b);
 702                 goto abort;
 703         }
 704
 705         if (sb->raid_disks <= 0)
 706                 goto abort;
 707
 708         if (md_csum_fold(calc_sb_csum(sb)) != md_csum_fold(sb->sb_csum)) {
 709                 printk(KERN_WARNING "md: invalid superblock checksum on %s\n",
 710                         b);
 711                 goto abort;
 712         }
 713
 714         rdev->preferred_minor = sb->md_minor;
 715         rdev->data_offset = 0;
 716         rdev->sb_size = MD_SB_BYTES;
 717
 718         if (sb->state & (1<<MD_SB_BITMAP_PRESENT)) {
 719                 if (sb->level != 1 && sb->level != 4
 720                     && sb->level != 5 && sb->level != 6
 721                     && sb->level != 10) {
 722                         /* FIXME use a better test */
 723                         printk(KERN_WARNING
 724                                "md: bitmaps not supported for this level.\n");
 725                         goto abort;
 726                 }
 727         }
 728
 729         if (sb->level == LEVEL_MULTIPATH)
 730                 rdev->desc_nr = -1;
 731         else
 732                 rdev->desc_nr = sb->this_disk.number;
 733
 734         if (refdev == 0)
 735                 ret = 1;
 736         else {
 737                 __u64 ev1, ev2;
 738                 mdp_super_t *refsb = (mdp_super_t*)page_address(refdev->sb_page);
 739                 if (!uuid_equal(refsb, sb)) {
 740                         printk(KERN_WARNING "md: %s has different UUID to %s\n",
 741                                 b, bdevname(refdev->bdev,b2));
 742                         goto abort;
 743                 }
 744                 if (!sb_equal(refsb, sb)) {
 745                         printk(KERN_WARNING "md: %s has same UUID"
 746                                " but different superblock to %s\n",
 747                                b, bdevname(refdev->bdev, b2));
 748                         goto abort;
 749                 }
 750                 ev1 = md_event(sb);
 751                 ev2 = md_event(refsb);
 752                 if (ev1 > ev2)
 753                         ret = 1;
 754                 else
 755                         ret = 0;
 756         }
 757         rdev->size = calc_dev_size(rdev, sb->chunk_size);
 758
 759         if (rdev->size < sb->size && sb->level > 1)
 760                 /* "this cannot possibly happen" ... */
 761                 ret = -EINVAL;
 762
 763  abort:
 764         return ret;
 765 }
 766
 767 /*
 768  * validate_super for 0.90.0
 769  */
 770 static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
 771 {
 772         mdp_disk_t *desc;
 773         mdp_super_t *sb = (mdp_super_t *)page_address(rdev->sb_page);
 774         __u64 ev1 = md_event(sb);
 775
 776         rdev->raid_disk = -1;
 777         clear_bit(Faulty, &rdev->flags);
 778         clear_bit(In_sync, &rdev->flags);
 779         clear_bit(WriteMostly, &rdev->flags);
 780         clear_bit(BarriersNotsupp, &rdev->flags);
 781
 782         if (mddev->raid_disks == 0) {
 783                 mddev->major_version = 0;
 784                 mddev->minor_version = sb->minor_version;
 785                 mddev->patch_version = sb->patch_version;
 786                 mddev->external = 0;
 787                 mddev->chunk_size = sb->chunk_size;
 788                 mddev->ctime = sb->ctime;
 789                 mddev->utime = sb->utime;
 790                 mddev->level = sb->level;
 791                 mddev->clevel[0] = 0;
 792                 mddev->layout = sb->layout;
 793                 mddev->raid_disks = sb->raid_disks;
 794                 mddev->size = sb->size;
 795                 mddev->events = ev1;
 796                 mddev->bitmap_offset = 0;
 797                 mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
 798
 799                 if (mddev->minor_version >= 91) {
 800                         mddev->reshape_position = sb->reshape_position;
 801                         mddev->delta_disks = sb->delta_disks;
 802                         mddev->new_level = sb->new_level;
 803                         mddev->new_layout = sb->new_layout;
 804                         mddev->new_chunk = sb->new_chunk;
 805                 } else {
 806                         mddev->reshape_position = MaxSector;
 807                         mddev->delta_disks = 0;
 808                         mddev->new_level = mddev->level;
 809                         mddev->new_layout = mddev->layout;
 810                         mddev->new_chunk = mddev->chunk_size;
 811                 }
 812
 813                 if (sb->state & (1<<MD_SB_CLEAN))
 814                         mddev->recovery_cp = MaxSector;
 815                 else {
 816                         if (sb->events_hi == sb->cp_events_hi &&
 817                                 sb->events_lo == sb->cp_events_lo) {
 818                                 mddev->recovery_cp = sb->recovery_cp;
 819                         } else
 820                                 mddev->recovery_cp = 0;
 821                 }
 822
 823                 memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
 824                 memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
 825                 memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
 826                 memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
 827
 828                 mddev->max_disks = MD_SB_DISKS;
 829
 830                 if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
 831                     mddev->bitmap_file == NULL)
 832                         mddev->bitmap_offset = mddev->default_bitmap_offset;
 833
 834         } else if (mddev->pers == NULL) {
 835                 /* Insist on good event counter while assembling */
 836                 ++ev1;
 837                 if (ev1 < mddev->events)
 838                         return -EINVAL;
 839         } else if (mddev->bitmap) {
 840                 /* if adding to array with a bitmap, then we can accept an
 841                  * older device ... but not too old.
 842                  */
 843                 if (ev1 < mddev->bitmap->events_cleared)
 844                         return 0;
 845         } else {
 846                 if (ev1 < mddev->events)
 847                         /* just a hot-add of a new device, leave raid_disk at -1 */
 848                         return 0;
 849         }
 850
 851         if (mddev->level != LEVEL_MULTIPATH) {
 852                 desc = sb->disks + rdev->desc_nr;
 853
 854                 if (desc->state & (1<<MD_DISK_FAULTY))
 855                         set_bit(Faulty, &rdev->flags);
 856                 else if (desc->state & (1<<MD_DISK_SYNC) /* &&
 857                             desc->raid_disk < mddev->raid_disks */) {
 858                         set_bit(In_sync, &rdev->flags);
 859                         rdev->raid_disk = desc->raid_disk;
 860                 }
 861                 if (desc->state & (1<<MD_DISK_WRITEMOSTLY))
 862                         set_bit(WriteMostly, &rdev->flags);
 863         } else /* MULTIPATH are always insync */
 864                 set_bit(In_sync, &rdev->flags);
 865         return 0;
 866 }
 867
 868 /*
 869  * sync_super for 0.90.0
 870  */
 871 static void super_90_sync(mddev_t *mddev, mdk_rdev_t *rdev)
 872 {
 873         mdp_super_t *sb;
 874         struct list_head *tmp;
 875         mdk_rdev_t *rdev2;
 876         int next_spare = mddev->raid_disks;
 877
 878
 879         /* make rdev->sb match mddev data..
 880          *
 881          * 1/ zero out disks
 882          * 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
 883          * 3/ any empty disks < next_spare become removed
 884          *
 885          * disks[0] gets initialised to REMOVED because
 886          * we cannot be sure from other fields if it has
 887          * been initialised or not.
 888          */
 889         int i;
 890         int active=0, working=0,failed=0,spare=0,nr_disks=0;
 891
 892         rdev->sb_size = MD_SB_BYTES;
 893
 894         sb = (mdp_super_t*)page_address(rdev->sb_page);
 895
 896         memset(sb, 0, sizeof(*sb));
 897
 898         sb->md_magic = MD_SB_MAGIC;
 899         sb->major_version = mddev->major_version;
 900         sb->patch_version = mddev->patch_version;
 901         sb->gvalid_words  = 0; /* ignored */
 902         memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
 903         memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
 904         memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
 905         memcpy(&sb->set_uuid3, mddev->uuid+12,4);
 906
 907         sb->ctime = mddev->ctime;
 908         sb->level = mddev->level;
 909         sb->size  = mddev->size;
 910         sb->raid_disks = mddev->raid_disks;
 911         sb->md_minor = mddev->md_minor;
 912         sb->not_persistent = 0;
 913         sb->utime = mddev->utime;
 914         sb->state = 0;
 915         sb->events_hi = (mddev->events>>32);
 916         sb->events_lo = (u32)mddev->events;
 917
 918         if (mddev->reshape_position == MaxSector)
 919                 sb->minor_version = 90;
 920         else {
 921                 sb->minor_version = 91;
 922                 sb->reshape_position = mddev->reshape_position;
 923                 sb->new_level = mddev->new_level;
 924                 sb->delta_disks = mddev->delta_disks;
 925                 sb->new_layout = mddev->new_layout;
 926                 sb->new_chunk = mddev->new_chunk;
 927         }
 928         mddev->minor_version = sb->minor_version;
 929         if (mddev->in_sync)
 930         {
 931                 sb->recovery_cp = mddev->recovery_cp;
 932                 sb->cp_events_hi = (mddev->events>>32);
 933                 sb->cp_events_lo = (u32)mddev->events;
 934                 if (mddev->recovery_cp == MaxSector)
 935                         sb->state = (1<< MD_SB_CLEAN);
 936         } else
 937                 sb->recovery_cp = 0;
 938
 939         sb->layout = mddev->layout;
 940         sb->chunk_size = mddev->chunk_size;
 941
 942         if (mddev->bitmap && mddev->bitmap_file == NULL)
 943                 sb->state |= (1<<MD_SB_BITMAP_PRESENT);
 944
 945         sb->disks[0].state = (1<<MD_DISK_REMOVED);
 946         rdev_for_each(rdev2, tmp, mddev) {
 947                 mdp_disk_t *d;
 948                 int desc_nr;
 949                 if (rdev2->raid_disk >= 0 && test_bit(In_sync, &rdev2->flags)
 950                     && !test_bit(Faulty, &rdev2->flags))
 951                         desc_nr = rdev2->raid_disk;
 952                 else
 953                         desc_nr = next_spare++;
 954                 rdev2->desc_nr = desc_nr;
 955                 d = &sb->disks[rdev2->desc_nr];
 956                 nr_disks++;
 957                 d->number = rdev2->desc_nr;
 958                 d->major = MAJOR(rdev2->bdev->bd_dev);
 959                 d->minor = MINOR(rdev2->bdev->bd_dev);
 960                 if (rdev2->raid_disk >= 0 && test_bit(In_sync, &rdev2->flags)
 961                     && !test_bit(Faulty, &rdev2->flags))
 962                         d->raid_disk = rdev2->raid_disk;
 963                 else
 964                         d->raid_disk = rdev2->desc_nr; /* compatibility */
 965                 if (test_bit(Faulty, &rdev2->flags))
 966                         d->state = (1<<MD_DISK_FAULTY);
 967                 else if (test_bit(In_sync, &rdev2->flags)) {
 968                         d->state = (1<<MD_DISK_ACTIVE);
 969                         d->state |= (1<<MD_DISK_SYNC);
 970                         active++;
 971                         working++;
 972                 } else {
 973                         d->state = 0;
 974                         spare++;
 975                         working++;
 976                 }
 977                 if (test_bit(WriteMostly, &rdev2->flags))
 978                         d->state |= (1<<MD_DISK_WRITEMOSTLY);
 979         }
 980         /* now set the "removed" and "faulty" bits on any missing devices */
 981         for (i=0 ; i < mddev->raid_disks ; i++) {
 982                 mdp_disk_t *d = &sb->disks[i];
 983                 if (d->state == 0 && d->number == 0) {
 984                         d->number = i;
 985                         d->raid_disk = i;
 986                         d->state = (1<<MD_DISK_REMOVED);
 987                         d->state |= (1<<MD_DISK_FAULTY);
 988                         failed++;
 989                 }
 990         }
 991         sb->nr_disks = nr_disks;
 992         sb->active_disks = active;
 993         sb->working_disks = working;
 994         sb->failed_disks = failed;
 995         sb->spare_disks = spare;
 996
 997         sb->this_disk = sb->disks[rdev->desc_nr];
 998         sb->sb_csum = calc_sb_csum(sb);
 999 }
1000
1001 /*
1002  * version 1 superblock
1003  */
1004
1005 static __le32 calc_sb_1_csum(struct mdp_superblock_1 * sb)
1006 {
1007         __le32 disk_csum;
1008         u32 csum;
1009         unsigned long long newcsum;
1010         int size = 256 + le32_to_cpu(sb->max_dev)*2;
1011         __le32 *isuper = (__le32*)sb;
1012         int i;
1013
1014         disk_csum = sb->sb_csum;
1015         sb->sb_csum = 0;
1016         newcsum = 0;
1017         for (i=0; size>=4; size -= 4 )
1018                 newcsum += le32_to_cpu(*isuper++);
1019
1020         if (size == 2)
1021                 newcsum += le16_to_cpu(*(__le16*) isuper);
1022
1023         csum = (newcsum & 0xffffffff) + (newcsum >> 32);
1024         sb->sb_csum = disk_csum;
1025         return cpu_to_le32(csum);
1026 }
1027
1028 static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
1029 {
1030         struct mdp_superblock_1 *sb;
1031         int ret;
1032         sector_t sb_offset;
1033         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1034         int bmask;
1035
1036         /*
1037          * Calculate the position of the superblock.
1038          * It is always aligned to a 4K boundary and
1039          * depeding on minor_version, it can be:
1040          * 0: At least 8K, but less than 12K, from end of device
1041          * 1: At start of device
1042          * 2: 4K from start of device.
1043          */
1044         switch(minor_version) {
1045         case 0:
1046                 sb_offset = rdev->bdev->bd_inode->i_size >> 9;
1047                 sb_offset -= 8*2;
1048                 sb_offset &= ~(sector_t)(4*2-1);
1049                 /* convert from sectors to K */
1050                 sb_offset /= 2;
1051                 break;
1052         case 1:
1053                 sb_offset = 0;
1054                 break;
1055         case 2:
1056                 sb_offset = 4;
1057                 break;
1058         default:
1059                 return -EINVAL;
1060         }
1061         rdev->sb_offset = sb_offset;
1062
1063         /* superblock is rarely larger than 1K, but it can be larger,
1064          * and it is safe to read 4k, so we do that
1065          */
1066         ret = read_disk_sb(rdev, 4096);
1067         if (ret) return ret;
1068
1069
1070         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1071
1072         if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
1073             sb->major_version != cpu_to_le32(1) ||
1074             le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
1075             le64_to_cpu(sb->super_offset) != (rdev->sb_offset<<1) ||
1076             (le32_to_cpu(sb->feature_map) & ~MD_FEATURE_ALL) != 0)
1077                 return -EINVAL;
1078
1079         if (calc_sb_1_csum(sb) != sb->sb_csum) {
1080                 printk("md: invalid superblock checksum on %s\n",
1081                         bdevname(rdev->bdev,b));
1082                 return -EINVAL;
1083         }
1084         if (le64_to_cpu(sb->data_size) < 10) {
1085                 printk("md: data_size too small on %s\n",
1086                        bdevname(rdev->bdev,b));
1087                 return -EINVAL;
1088         }
1089         if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET)) {
1090                 if (sb->level != cpu_to_le32(1) &&
1091                     sb->level != cpu_to_le32(4) &&
1092                     sb->level != cpu_to_le32(5) &&
1093                     sb->level != cpu_to_le32(6) &&
1094                     sb->level != cpu_to_le32(10)) {
1095                         printk(KERN_WARNING
1096                                "md: bitmaps not supported for this level.\n");
1097                         return -EINVAL;
1098                 }
1099         }
1100
1101         rdev->preferred_minor = 0xffff;
1102         rdev->data_offset = le64_to_cpu(sb->data_offset);
1103         atomic_set(&rdev->corrected_errors, le32_to_cpu(sb->cnt_corrected_read));
1104
1105         rdev->sb_size = le32_to_cpu(sb->max_dev) * 2 + 256;
1106         bmask = queue_hardsect_size(rdev->bdev->bd_disk->queue)-1;
1107         if (rdev->sb_size & bmask)
1108                 rdev->sb_size = (rdev->sb_size | bmask) + 1;
1109
1110         if (minor_version
1111             && rdev->data_offset < sb_offset + (rdev->sb_size/512))
1112                 return -EINVAL;
1113
1114         if (sb->level == cpu_to_le32(LEVEL_MULTIPATH))
1115                 rdev->desc_nr = -1;
1116         else
1117                 rdev->desc_nr = le32_to_cpu(sb->dev_number);
1118
1119         if (refdev == 0)
1120                 ret = 1;
1121         else {
1122                 __u64 ev1, ev2;
1123                 struct mdp_superblock_1 *refsb =
1124                         (struct mdp_superblock_1*)page_address(refdev->sb_page);
1125
1126                 if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
1127                     sb->level != refsb->level ||
1128                     sb->layout != refsb->layout ||
1129                     sb->chunksize != refsb->chunksize) {
1130                         printk(KERN_WARNING "md: %s has strangely different"
1131                                 " superblock to %s\n",
1132                                 bdevname(rdev->bdev,b),
1133                                 bdevname(refdev->bdev,b2));
1134                         return -EINVAL;
1135                 }
1136                 ev1 = le64_to_cpu(sb->events);
1137                 ev2 = le64_to_cpu(refsb->events);
1138
1139                 if (ev1 > ev2)
1140                         ret = 1;
1141                 else
1142                         ret = 0;
1143         }
1144         if (minor_version)
1145                 rdev->size = ((rdev->bdev->bd_inode->i_size>>9) - le64_to_cpu(sb->data_offset)) / 2;
1146         else
1147                 rdev->size = rdev->sb_offset;
1148         if (rdev->size < le64_to_cpu(sb->data_size)/2)
1149                 return -EINVAL;
1150         rdev->size = le64_to_cpu(sb->data_size)/2;
1151         if (le32_to_cpu(sb->chunksize))
1152                 rdev->size &= ~((sector_t)le32_to_cpu(sb->chunksize)/2 - 1);
1153
1154         if (le64_to_cpu(sb->size) > rdev->size*2)
1155                 return -EINVAL;
1156         return ret;
1157 }
1158
1159 static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
1160 {
1161         struct mdp_superblock_1 *sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1162         __u64 ev1 = le64_to_cpu(sb->events);
1163
1164         rdev->raid_disk = -1;
1165         clear_bit(Faulty, &rdev->flags);
1166         clear_bit(In_sync, &rdev->flags);
1167         clear_bit(WriteMostly, &rdev->flags);
1168         clear_bit(BarriersNotsupp, &rdev->flags);
1169
1170         if (mddev->raid_disks == 0) {
1171                 mddev->major_version = 1;
1172                 mddev->patch_version = 0;
1173                 mddev->external = 0;
1174                 mddev->chunk_size = le32_to_cpu(sb->chunksize) << 9;
1175                 mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);
1176                 mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);
1177                 mddev->level = le32_to_cpu(sb->level);
1178                 mddev->clevel[0] = 0;
1179                 mddev->layout = le32_to_cpu(sb->layout);
1180                 mddev->raid_disks = le32_to_cpu(sb->raid_disks);
1181                 mddev->size = le64_to_cpu(sb->size)/2;
1182                 mddev->events = ev1;
1183                 mddev->bitmap_offset = 0;
1184                 mddev->default_bitmap_offset = 1024 >> 9;
1185
1186                 mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
1187                 memcpy(mddev->uuid, sb->set_uuid, 16);
1188
1189                 mddev->max_disks =  (4096-256)/2;
1190
1191                 if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET) &&
1192                     mddev->bitmap_file == NULL )
1193                         mddev->bitmap_offset = (__s32)le32_to_cpu(sb->bitmap_offset);
1194
1195                 if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE)) {
1196                         mddev->reshape_position = le64_to_cpu(sb->reshape_position);
1197                         mddev->delta_disks = le32_to_cpu(sb->delta_disks);
1198                         mddev->new_level = le32_to_cpu(sb->new_level);
1199                         mddev->new_layout = le32_to_cpu(sb->new_layout);
1200                         mddev->new_chunk = le32_to_cpu(sb->new_chunk)<<9;
1201                 } else {
1202                         mddev->reshape_position = MaxSector;
1203                         mddev->delta_disks = 0;
1204                         mddev->new_level = mddev->level;
1205                         mddev->new_layout = mddev->layout;
1206                         mddev->new_chunk = mddev->chunk_size;
1207                 }
1208
1209         } else if (mddev->pers == NULL) {
1210                 /* Insist of good event counter while assembling */
1211                 ++ev1;
1212                 if (ev1 < mddev->events)
1213                         return -EINVAL;
1214         } else if (mddev->bitmap) {
1215                 /* If adding to array with a bitmap, then we can accept an
1216                  * older device, but not too old.
1217                  */
1218                 if (ev1 < mddev->bitmap->events_cleared)
1219                         return 0;
1220         } else {
1221                 if (ev1 < mddev->events)
1222                         /* just a hot-add of a new device, leave raid_disk at -1 */
1223                         return 0;
1224         }
1225         if (mddev->level != LEVEL_MULTIPATH) {
1226                 int role;
1227                 role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
1228                 switch(role) {
1229                 case 0xffff: /* spare */
1230                         break;
1231                 case 0xfffe: /* faulty */
1232                         set_bit(Faulty, &rdev->flags);
1233                         break;
1234                 default:
1235                         if ((le32_to_cpu(sb->feature_map) &
1236                              MD_FEATURE_RECOVERY_OFFSET))
1237                                 rdev->recovery_offset = le64_to_cpu(sb->recovery_offset);
1238                         else
1239                                 set_bit(In_sync, &rdev->flags);
1240                         rdev->raid_disk = role;
1241                         break;
1242                 }
1243                 if (sb->devflags & WriteMostly1)
1244                         set_bit(WriteMostly, &rdev->flags);
1245         } else /* MULTIPATH are always insync */
1246                 set_bit(In_sync, &rdev->flags);
1247
1248         return 0;
1249 }
1250
1251 static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
1252 {
1253         struct mdp_superblock_1 *sb;
1254         struct list_head *tmp;
1255         mdk_rdev_t *rdev2;
1256         int max_dev, i;
1257         /* make rdev->sb match mddev and rdev data. */
1258
1259         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1260
1261         sb->feature_map = 0;
1262         sb->pad0 = 0;
1263         sb->recovery_offset = cpu_to_le64(0);
1264         memset(sb->pad1, 0, sizeof(sb->pad1));
1265         memset(sb->pad2, 0, sizeof(sb->pad2));
1266         memset(sb->pad3, 0, sizeof(sb->pad3));
1267
1268         sb->utime = cpu_to_le64((__u64)mddev->utime);
1269         sb->events = cpu_to_le64(mddev->events);
1270         if (mddev->in_sync)
1271                 sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
1272         else
1273                 sb->resync_offset = cpu_to_le64(0);
1274
1275         sb->cnt_corrected_read = cpu_to_le32(atomic_read(&rdev->corrected_errors));
1276
1277         sb->raid_disks = cpu_to_le32(mddev->raid_disks);
1278         sb->size = cpu_to_le64(mddev->size<<1);
1279
1280         if (mddev->bitmap && mddev->bitmap_file == NULL) {
1281                 sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_offset);
1282                 sb->feature_map = cpu_to_le32(MD_FEATURE_BITMAP_OFFSET);
1283         }
1284
1285         if (rdev->raid_disk >= 0 &&
1286             !test_bit(In_sync, &rdev->flags) &&
1287             rdev->recovery_offset > 0) {
1288                 sb->feature_map |= cpu_to_le32(MD_FEATURE_RECOVERY_OFFSET);
1289                 sb->recovery_offset = cpu_to_le64(rdev->recovery_offset);
1290         }
1291
1292         if (mddev->reshape_position != MaxSector) {
1293                 sb->feature_map |= cpu_to_le32(MD_FEATURE_RESHAPE_ACTIVE);
1294                 sb->reshape_position = cpu_to_le64(mddev->reshape_position);
1295                 sb->new_layout = cpu_to_le32(mddev->new_layout);
1296                 sb->delta_disks = cpu_to_le32(mddev->delta_disks);
1297                 sb->new_level = cpu_to_le32(mddev->new_level);
1298                 sb->new_chunk = cpu_to_le32(mddev->new_chunk>>9);
1299         }
1300
1301         max_dev = 0;
1302         rdev_for_each(rdev2, tmp, mddev)
1303                 if (rdev2->desc_nr+1 > max_dev)
1304                         max_dev = rdev2->desc_nr+1;
1305
1306         if (max_dev > le32_to_cpu(sb->max_dev))
1307                 sb->max_dev = cpu_to_le32(max_dev);
1308         for (i=0; i<max_dev;i++)
1309                 sb->dev_roles[i] = cpu_to_le16(0xfffe);
1310
1311         rdev_for_each(rdev2, tmp, mddev) {
1312                 i = rdev2->desc_nr;
1313                 if (test_bit(Faulty, &rdev2->flags))
1314                         sb->dev_roles[i] = cpu_to_le16(0xfffe);
1315                 else if (test_bit(In_sync, &rdev2->flags))
1316                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1317                 else if (rdev2->raid_disk >= 0 && rdev2->recovery_offset > 0)
1318                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1319                 else
1320                         sb->dev_roles[i] = cpu_to_le16(0xffff);
1321         }
1322
1323         sb->sb_csum = calc_sb_1_csum(sb);
1324 }
1325
1326
1327 static struct super_type super_types[] = {
1328         [0] = {
1329                 .name   = "0.90.0",
1330                 .owner  = THIS_MODULE,
1331                 .load_super     = super_90_load,
1332                 .validate_super = super_90_validate,
1333                 .sync_super     = super_90_sync,
1334         },
1335         [1] = {
1336                 .name   = "md-1",
1337                 .owner  = THIS_MODULE,
1338                 .load_super     = super_1_load,
1339                 .validate_super = super_1_validate,
1340                 .sync_super     = super_1_sync,
1341         },
1342 };
1343
1344 static int match_mddev_units(mddev_t *mddev1, mddev_t *mddev2)
1345 {
1346         struct list_head *tmp, *tmp2;
1347         mdk_rdev_t *rdev, *rdev2;
1348
1349         rdev_for_each(rdev, tmp, mddev1)
1350                 rdev_for_each(rdev2, tmp2, mddev2)
1351                         if (rdev->bdev->bd_contains ==
1352                             rdev2->bdev->bd_contains)
1353                                 return 1;
1354
1355         return 0;
1356 }
1357
1358 static LIST_HEAD(pending_raid_disks);
1359
1360 static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
1361 {
1362         char b[BDEVNAME_SIZE];
1363         struct kobject *ko;
1364         char *s;
1365         int err;
1366
1367         if (rdev->mddev) {
1368                 MD_BUG();
1369                 return -EINVAL;
1370         }
1371         /* make sure rdev->size exceeds mddev->size */
1372         if (rdev->size && (mddev->size == 0 || rdev->size < mddev->size)) {
1373                 if (mddev->pers) {
1374                         /* Cannot change size, so fail
1375                          * If mddev->level <= 0, then we don't care
1376                          * about aligning sizes (e.g. linear)
1377                          */
1378                         if (mddev->level > 0)
1379                                 return -ENOSPC;
1380                 } else
1381                         mddev->size = rdev->size;
1382         }
1383
1384         /* Verify rdev->desc_nr is unique.
1385          * If it is -1, assign a free number, else
1386          * check number is not in use
1387          */
1388         if (rdev->desc_nr < 0) {
1389                 int choice = 0;
1390                 if (mddev->pers) choice = mddev->raid_disks;
1391                 while (find_rdev_nr(mddev, choice))
1392                         choice++;
1393                 rdev->desc_nr = choice;
1394         } else {
1395                 if (find_rdev_nr(mddev, rdev->desc_nr))
1396                         return -EBUSY;
1397         }
1398         bdevname(rdev->bdev,b);
1399         while ( (s=strchr(b, '/')) != NULL)
1400                 *s = '!';
1401
1402         rdev->mddev = mddev;
1403         printk(KERN_INFO "md: bind<%s>\n", b);
1404
1405         if ((err = kobject_add(&rdev->kobj, &mddev->kobj, "dev-%s", b)))
1406                 goto fail;
1407
1408         if (rdev->bdev->bd_part)
1409                 ko = &rdev->bdev->bd_part->dev.kobj;
1410         else
1411                 ko = &rdev->bdev->bd_disk->dev.kobj;
1412         if ((err = sysfs_create_link(&rdev->kobj, ko, "block"))) {
1413                 kobject_del(&rdev->kobj);
1414                 goto fail;
1415         }
1416         list_add(&rdev->same_set, &mddev->disks);
1417         bd_claim_by_disk(rdev->bdev, rdev->bdev->bd_holder, mddev->gendisk);
1418         return 0;
1419
1420  fail:
1421         printk(KERN_WARNING "md: failed to register dev-%s for %s\n",
1422                b, mdname(mddev));
1423         return err;
1424 }
1425
1426 static void md_delayed_delete(struct work_struct *ws)
1427 {
1428         mdk_rdev_t *rdev = container_of(ws, mdk_rdev_t, del_work);
1429         kobject_del(&rdev->kobj);
1430         kobject_put(&rdev->kobj);
1431 }
1432
1433 static void unbind_rdev_from_array(mdk_rdev_t * rdev)
1434 {
1435         char b[BDEVNAME_SIZE];
1436         if (!rdev->mddev) {
1437                 MD_BUG();
1438                 return;
1439         }
1440         bd_release_from_disk(rdev->bdev, rdev->mddev->gendisk);
1441         list_del_init(&rdev->same_set);
1442         printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
1443         rdev->mddev = NULL;
1444         sysfs_remove_link(&rdev->kobj, "block");
1445
1446         /* We need to delay this, otherwise we can deadlock when
1447          * writing to 'remove' to "dev/state"
1448          */
1449         INIT_WORK(&rdev->del_work, md_delayed_delete);
1450         kobject_get(&rdev->kobj);
1451         schedule_work(&rdev->del_work);
1452 }
1453
1454 /*
1455  * prevent the device from being mounted, repartitioned or
1456  * otherwise reused by a RAID array (or any other kernel
1457  * subsystem), by bd_claiming the device.
1458  */
1459 static int lock_rdev(mdk_rdev_t *rdev, dev_t dev, int shared)
1460 {
1461         int err = 0;
1462         struct block_device *bdev;
1463         char b[BDEVNAME_SIZE];
1464
1465         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
1466         if (IS_ERR(bdev)) {
1467                 printk(KERN_ERR "md: could not open %s.\n",
1468                         __bdevname(dev, b));
1469                 return PTR_ERR(bdev);
1470         }
1471         err = bd_claim(bdev, shared ? (mdk_rdev_t *)lock_rdev : rdev);
1472         if (err) {
1473                 printk(KERN_ERR "md: could not bd_claim %s.\n",
1474                         bdevname(bdev, b));
1475                 blkdev_put(bdev);
1476                 return err;
1477         }
1478         if (!shared)
1479                 set_bit(AllReserved, &rdev->flags);
1480         rdev->bdev = bdev;
1481         return err;
1482 }
1483
1484 static void unlock_rdev(mdk_rdev_t *rdev)
1485 {
1486         struct block_device *bdev = rdev->bdev;
1487         rdev->bdev = NULL;
1488         if (!bdev)
1489                 MD_BUG();
1490         bd_release(bdev);
1491         blkdev_put(bdev);
1492 }
1493
1494 void md_autodetect_dev(dev_t dev);
1495
1496 static void export_rdev(mdk_rdev_t * rdev)
1497 {
1498         char b[BDEVNAME_SIZE];
1499         printk(KERN_INFO "md: export_rdev(%s)\n",
1500                 bdevname(rdev->bdev,b));
1501         if (rdev->mddev)
1502                 MD_BUG();
1503         free_disk_sb(rdev);
1504         list_del_init(&rdev->same_set);
1505 #ifndef MODULE
1506         if (test_bit(AutoDetected, &rdev->flags))
1507                 md_autodetect_dev(rdev->bdev->bd_dev);
1508 #endif
1509         unlock_rdev(rdev);
1510         kobject_put(&rdev->kobj);
1511 }
1512
1513 static void kick_rdev_from_array(mdk_rdev_t * rdev)
1514 {
1515         unbind_rdev_from_array(rdev);
1516         export_rdev(rdev);
1517 }
1518
1519 static void export_array(mddev_t *mddev)
1520 {
1521         struct list_head *tmp;
1522         mdk_rdev_t *rdev;
1523
1524         rdev_for_each(rdev, tmp, mddev) {
1525                 if (!rdev->mddev) {
1526                         MD_BUG();
1527                         continue;
1528                 }
1529                 kick_rdev_from_array(rdev);
1530         }
1531         if (!list_empty(&mddev->disks))
1532                 MD_BUG();
1533         mddev->raid_disks = 0;
1534         mddev->major_version = 0;
1535 }
1536
1537 static void print_desc(mdp_disk_t *desc)
1538 {
1539         printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
1540                 desc->major,desc->minor,desc->raid_disk,desc->state);
1541 }
1542
1543 static void print_sb(mdp_super_t *sb)
1544 {
1545         int i;
1546
1547         printk(KERN_INFO
1548                 "md:  SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
1549                 sb->major_version, sb->minor_version, sb->patch_version,
1550                 sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
1551                 sb->ctime);
1552         printk(KERN_INFO "md:     L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
1553                 sb->level, sb->size, sb->nr_disks, sb->raid_disks,
1554                 sb->md_minor, sb->layout, sb->chunk_size);
1555         printk(KERN_INFO "md:     UT:%08x ST:%d AD:%d WD:%d"
1556                 " FD:%d SD:%d CSUM:%08x E:%08lx\n",
1557                 sb->utime, sb->state, sb->active_disks, sb->working_disks,
1558                 sb->failed_disks, sb->spare_disks,
1559                 sb->sb_csum, (unsigned long)sb->events_lo);
1560
1561         printk(KERN_INFO);
1562         for (i = 0; i < MD_SB_DISKS; i++) {
1563                 mdp_disk_t *desc;
1564
1565                 desc = sb->disks + i;
1566                 if (desc->number || desc->major || desc->minor ||
1567                     desc->raid_disk || (desc->state && (desc->state != 4))) {
1568                         printk("     D %2d: ", i);
1569                         print_desc(desc);
1570                 }
1571         }
1572         printk(KERN_INFO "md:     THIS: ");
1573         print_desc(&sb->this_disk);
1574
1575 }
1576
1577 static void print_rdev(mdk_rdev_t *rdev)
1578 {
1579         char b[BDEVNAME_SIZE];
1580         printk(KERN_INFO "md: rdev %s, SZ:%08llu F:%d S:%d DN:%u\n",
1581                 bdevname(rdev->bdev,b), (unsigned long long)rdev->size,
1582                 test_bit(Faulty, &rdev->flags), test_bit(In_sync, &rdev->flags),
1583                 rdev->desc_nr);
1584         if (rdev->sb_loaded) {
1585                 printk(KERN_INFO "md: rdev superblock:\n");
1586                 print_sb((mdp_super_t*)page_address(rdev->sb_page));
1587         } else
1588                 printk(KERN_INFO "md: no rdev superblock!\n");
1589 }
1590
1591 static void md_print_devices(void)
1592 {
1593         struct list_head *tmp, *tmp2;
1594         mdk_rdev_t *rdev;
1595         mddev_t *mddev;
1596         char b[BDEVNAME_SIZE];
1597
1598         printk("\n");
1599         printk("md:     **********************************\n");
1600         printk("md:     * <COMPLETE RAID STATE PRINTOUT> *\n");
1601         printk("md:     **********************************\n");
1602         for_each_mddev(mddev, tmp) {
1603
1604                 if (mddev->bitmap)
1605                         bitmap_print_sb(mddev->bitmap);
1606                 else
1607                         printk("%s: ", mdname(mddev));
1608                 rdev_for_each(rdev, tmp2, mddev)
1609                         printk("<%s>", bdevname(rdev->bdev,b));
1610                 printk("\n");
1611
1612                 rdev_for_each(rdev, tmp2, mddev)
1613                         print_rdev(rdev);
1614         }
1615         printk("md:     **********************************\n");
1616         printk("\n");
1617 }
1618
1619
1620 static void sync_sbs(mddev_t * mddev, int nospares)
1621 {
1622         /* Update each superblock (in-memory image), but
1623          * if we are allowed to, skip spares which already
1624          * have the right event counter, or have one earlier
1625          * (which would mean they aren't being marked as dirty
1626          * with the rest of the array)
1627          */
1628         mdk_rdev_t *rdev;
1629         struct list_head *tmp;
1630
1631         rdev_for_each(rdev, tmp, mddev) {
1632                 if (rdev->sb_events == mddev->events ||
1633                     (nospares &&
1634                      rdev->raid_disk < 0 &&
1635                      (rdev->sb_events&1)==0 &&
1636                      rdev->sb_events+1 == mddev->events)) {
1637                         /* Don't update this superblock */
1638                         rdev->sb_loaded = 2;
1639                 } else {
1640                         super_types[mddev->major_version].
1641                                 sync_super(mddev, rdev);
1642                         rdev->sb_loaded = 1;
1643                 }
1644         }
1645 }
1646
1647 static void md_update_sb(mddev_t * mddev, int force_change)
1648 {
1649         struct list_head *tmp;
1650         mdk_rdev_t *rdev;
1651         int sync_req;
1652         int nospares = 0;
1653
1654 repeat:
1655         spin_lock_irq(&mddev->write_lock);
1656
1657         set_bit(MD_CHANGE_PENDING, &mddev->flags);
1658         if (test_and_clear_bit(MD_CHANGE_DEVS, &mddev->flags))
1659                 force_change = 1;
1660         if (test_and_clear_bit(MD_CHANGE_CLEAN, &mddev->flags))
1661                 /* just a clean<-> dirty transition, possibly leave spares alone,
1662                  * though if events isn't the right even/odd, we will have to do
1663                  * spares after all
1664                  */
1665                 nospares = 1;
1666         if (force_change)
1667                 nospares = 0;
1668         if (mddev->degraded)
1669                 /* If the array is degraded, then skipping spares is both
1670                  * dangerous and fairly pointless.
1671                  * Dangerous because a device that was removed from the array
1672                  * might have a event_count that still looks up-to-date,
1673                  * so it can be re-added without a resync.
1674                  * Pointless because if there are any spares to skip,
1675                  * then a recovery will happen and soon that array won't
1676                  * be degraded any more and the spare can go back to sleep then.
1677                  */
1678                 nospares = 0;
1679
1680         sync_req = mddev->in_sync;
1681         mddev->utime = get_seconds();
1682
1683         /* If this is just a dirty<->clean transition, and the array is clean
1684          * and 'events' is odd, we can roll back to the previous clean state */
1685         if (nospares
1686             && (mddev->in_sync && mddev->recovery_cp == MaxSector)
1687             && (mddev->events & 1)
1688             && mddev->events != 1)
1689                 mddev->events--;
1690         else {
1691                 /* otherwise we have to go forward and ... */
1692                 mddev->events ++;
1693                 if (!mddev->in_sync || mddev->recovery_cp != MaxSector) { /* not clean */
1694                         /* .. if the array isn't clean, insist on an odd 'events' */
1695                         if ((mddev->events&1)==0) {
1696                                 mddev->events++;
1697                                 nospares = 0;
1698                         }
1699                 } else {
1700                         /* otherwise insist on an even 'events' (for clean states) */
1701                         if ((mddev->events&1)) {
1702                                 mddev->events++;
1703                                 nospares = 0;
1704                         }
1705                 }
1706         }
1707
1708         if (!mddev->events) {
1709                 /*
1710                  * oops, this 64-bit counter should never wrap.
1711                  * Either we are in around ~1 trillion A.C., assuming
1712                  * 1 reboot per second, or we have a bug:
1713                  */
1714                 MD_BUG();
1715                 mddev->events --;
1716         }
1717
1718         /*
1719          * do not write anything to disk if using
1720          * nonpersistent superblocks
1721          */
1722         if (!mddev->persistent) {
1723                 if (!mddev->external)
1724                         clear_bit(MD_CHANGE_PENDING, &mddev->flags);
1725
1726                 spin_unlock_irq(&mddev->write_lock);
1727                 wake_up(&mddev->sb_wait);
1728                 return;
1729         }
1730         sync_sbs(mddev, nospares);
1731         spin_unlock_irq(&mddev->write_lock);
1732
1733         dprintk(KERN_INFO
1734                 "md: updating %s RAID superblock on device (in sync %d)\n",
1735                 mdname(mddev),mddev->in_sync);
1736
1737         bitmap_update_sb(mddev->bitmap);
1738         rdev_for_each(rdev, tmp, mddev) {
1739                 char b[BDEVNAME_SIZE];
1740                 dprintk(KERN_INFO "md: ");
1741                 if (rdev->sb_loaded != 1)
1742                         continue; /* no noise on spare devices */
1743                 if (test_bit(Faulty, &rdev->flags))
1744                         dprintk("(skipping faulty ");
1745
1746                 dprintk("%s ", bdevname(rdev->bdev,b));
1747                 if (!test_bit(Faulty, &rdev->flags)) {
1748                         md_super_write(mddev,rdev,
1749                                        rdev->sb_offset<<1, rdev->sb_size,
1750                                        rdev->sb_page);
1751                         dprintk(KERN_INFO "(write) %s's sb offset: %llu\n",
1752                                 bdevname(rdev->bdev,b),
1753                                 (unsigned long long)rdev->sb_offset);
1754                         rdev->sb_events = mddev->events;
1755
1756                 } else
1757                         dprintk(")\n");
1758                 if (mddev->level == LEVEL_MULTIPATH)
1759                         /* only need to write one superblock... */
1760                         break;
1761         }
1762         md_super_wait(mddev);
1763         /* if there was a failure, MD_CHANGE_DEVS was set, and we re-write super */
1764
1765         spin_lock_irq(&mddev->write_lock);
1766         if (mddev->in_sync != sync_req ||
1767             test_bit(MD_CHANGE_DEVS, &mddev->flags)) {
1768                 /* have to write it out again */
1769                 spin_unlock_irq(&mddev->write_lock);
1770                 goto repeat;
1771         }
1772         clear_bit(MD_CHANGE_PENDING, &mddev->flags);
1773         spin_unlock_irq(&mddev->write_lock);
1774         wake_up(&mddev->sb_wait);
1775
1776 }
1777
1778 /* words written to sysfs files may, or my not, be \n terminated.
1779  * We want to accept with case. For this we use cmd_match.
1780  */
1781 static int cmd_match(const char *cmd, const char *str)
1782 {
1783         /* See if cmd, written into a sysfs file, matches
1784          * str.  They must either be the same, or cmd can
1785          * have a trailing newline
1786          */
1787         while (*cmd && *str && *cmd == *str) {
1788                 cmd++;
1789                 str++;
1790         }
1791         if (*cmd == '\n')
1792                 cmd++;
1793         if (*str || *cmd)
1794                 return 0;
1795         return 1;
1796 }
1797
1798 struct rdev_sysfs_entry {
1799         struct attribute attr;
1800         ssize_t (*show)(mdk_rdev_t *, char *);
1801         ssize_t (*store)(mdk_rdev_t *, const char *, size_t);
1802 };
1803
1804 static ssize_t
1805 state_show(mdk_rdev_t *rdev, char *page)
1806 {
1807         char *sep = "";
1808         size_t len = 0;
1809
1810         if (test_bit(Faulty, &rdev->flags)) {
1811                 len+= sprintf(page+len, "%sfaulty",sep);
1812                 sep = ",";
1813         }
1814         if (test_bit(In_sync, &rdev->flags)) {
1815                 len += sprintf(page+len, "%sin_sync",sep);
1816                 sep = ",";
1817         }
1818         if (test_bit(WriteMostly, &rdev->flags)) {
1819                 len += sprintf(page+len, "%swrite_mostly",sep);
1820                 sep = ",";
1821         }
1822         if (!test_bit(Faulty, &rdev->flags) &&
1823             !test_bit(In_sync, &rdev->flags)) {
1824                 len += sprintf(page+len, "%sspare", sep);
1825                 sep = ",";
1826         }
1827         return len+sprintf(page+len, "\n");
1828 }
1829
1830 static ssize_t
1831 state_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1832 {
1833         /* can write
1834          *  faulty  - simulates and error
1835          *  remove  - disconnects the device
1836          *  writemostly - sets write_mostly
1837          *  -writemostly - clears write_mostly
1838          */
1839         int err = -EINVAL;
1840         if (cmd_match(buf, "faulty") && rdev->mddev->pers) {
1841                 md_error(rdev->mddev, rdev);
1842                 err = 0;
1843         } else if (cmd_match(buf, "remove")) {
1844                 if (rdev->raid_disk >= 0)
1845                         err = -EBUSY;
1846                 else {
1847                         mddev_t *mddev = rdev->mddev;
1848                         kick_rdev_from_array(rdev);
1849                         if (mddev->pers)
1850                                 md_update_sb(mddev, 1);
1851                         md_new_event(mddev);
1852                         err = 0;
1853                 }
1854         } else if (cmd_match(buf, "writemostly")) {
1855                 set_bit(WriteMostly, &rdev->flags);
1856                 err = 0;
1857         } else if (cmd_match(buf, "-writemostly")) {
1858                 clear_bit(WriteMostly, &rdev->flags);
1859                 err = 0;
1860         }
1861         return err ? err : len;
1862 }
1863 static struct rdev_sysfs_entry rdev_state =
1864 __ATTR(state, S_IRUGO|S_IWUSR, state_show, state_store);
1865
1866 static ssize_t
1867 super_show(mdk_rdev_t *rdev, char *page)
1868 {
1869         if (rdev->sb_loaded && rdev->sb_size) {
1870                 memcpy(page, page_address(rdev->sb_page), rdev->sb_size);
1871                 return rdev->sb_size;
1872         } else
1873                 return 0;
1874 }
1875 static struct rdev_sysfs_entry rdev_super = __ATTR_RO(super);
1876
1877 static ssize_t
1878 errors_show(mdk_rdev_t *rdev, char *page)
1879 {
1880         return sprintf(page, "%d\n", atomic_read(&rdev->corrected_errors));
1881 }
1882
1883 static ssize_t
1884 errors_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1885 {
1886         char *e;
1887         unsigned long n = simple_strtoul(buf, &e, 10);
1888         if (*buf && (*e == 0 || *e == '\n')) {
1889                 atomic_set(&rdev->corrected_errors, n);
1890                 return len;
1891         }
1892         return -EINVAL;
1893 }
1894 static struct rdev_sysfs_entry rdev_errors =
1895 __ATTR(errors, S_IRUGO|S_IWUSR, errors_show, errors_store);
1896
1897 static ssize_t
1898 slot_show(mdk_rdev_t *rdev, char *page)
1899 {
1900         if (rdev->raid_disk < 0)
1901                 return sprintf(page, "none\n");
1902         else
1903                 return sprintf(page, "%d\n", rdev->raid_disk);
1904 }
1905
1906 static ssize_t
1907 slot_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1908 {
1909         char *e;
1910         int err;
1911         char nm[20];
1912         int slot = simple_strtoul(buf, &e, 10);
1913         if (strncmp(buf, "none", 4)==0)
1914                 slot = -1;
1915         else if (e==buf || (*e && *e!= '\n'))
1916                 return -EINVAL;
1917         if (rdev->mddev->pers) {
1918                 /* Setting 'slot' on an active array requires also
1919                  * updating the 'rd%d' link, and communicating
1920                  * with the personality with ->hot_*_disk.
1921                  * For now we only support removing
1922                  * failed/spare devices.  This normally happens automatically,
1923                  * but not when the metadata is externally managed.
1924                  */
1925                 if (slot != -1)
1926                         return -EBUSY;
1927                 if (rdev->raid_disk == -1)
1928                         return -EEXIST;
1929                 /* personality does all needed checks */
1930                 if (rdev->mddev->pers->hot_add_disk == NULL)
1931                         return -EINVAL;
1932                 err = rdev->mddev->pers->
1933                         hot_remove_disk(rdev->mddev, rdev->raid_disk);
1934                 if (err)
1935                         return err;
1936                 sprintf(nm, "rd%d", rdev->raid_disk);
1937                 sysfs_remove_link(&rdev->mddev->kobj, nm);
1938                 set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
1939                 md_wakeup_thread(rdev->mddev->thread);
1940         } else {
1941                 if (slot >= rdev->mddev->raid_disks)
1942                         return -ENOSPC;
1943                 rdev->raid_disk = slot;
1944                 /* assume it is working */
1945                 clear_bit(Faulty, &rdev->flags);
1946                 clear_bit(WriteMostly, &rdev->flags);
1947                 set_bit(In_sync, &rdev->flags);
1948         }
1949         return len;
1950 }
1951
1952
1953 static struct rdev_sysfs_entry rdev_slot =
1954 __ATTR(slot, S_IRUGO|S_IWUSR, slot_show, slot_store);
1955
1956 static ssize_t
1957 offset_show(mdk_rdev_t *rdev, char *page)
1958 {
1959         return sprintf(page, "%llu\n", (unsigned long long)rdev->data_offset);
1960 }
1961
1962 static ssize_t
1963 offset_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1964 {
1965         char *e;
1966         unsigned long long offset = simple_strtoull(buf, &e, 10);
1967         if (e==buf || (*e && *e != '\n'))
1968                 return -EINVAL;
1969         if (rdev->mddev->pers)
1970                 return -EBUSY;
1971         if (rdev->size && rdev->mddev->external)
1972                 /* Must set offset before size, so overlap checks
1973                  * can be sane */
1974                 return -EBUSY;
1975         rdev->data_offset = offset;
1976         return len;
1977 }
1978
1979 static struct rdev_sysfs_entry rdev_offset =
1980 __ATTR(offset, S_IRUGO|S_IWUSR, offset_show, offset_store);
1981
1982 static ssize_t
1983 rdev_size_show(mdk_rdev_t *rdev, char *page)
1984 {
1985         return sprintf(page, "%llu\n", (unsigned long long)rdev->size);
1986 }
1987
1988 static int overlaps(sector_t s1, sector_t l1, sector_t s2, sector_t l2)
1989 {
1990         /* check if two start/length pairs overlap */
1991         if (s1+l1 <= s2)
1992                 return 0;
1993         if (s2+l2 <= s1)
1994                 return 0;
1995         return 1;
1996 }
1997
1998 static ssize_t
1999 rdev_size_store(mdk_rdev_t *rdev, const char *buf, size_t len)
2000 {
2001         char *e;
2002         unsigned long long size = simple_strtoull(buf, &e, 10);
2003         unsigned long long oldsize = rdev->size;
2004         mddev_t *my_mddev = rdev->mddev;
2005
2006         if (e==buf || (*e && *e != '\n'))
2007                 return -EINVAL;
2008         if (my_mddev->pers)
2009                 return -EBUSY;
2010         rdev->size = size;
2011         if (size > oldsize && rdev->mddev->external) {
2012                 /* need to check that all other rdevs with the same ->bdev
2013                  * do not overlap.  We need to unlock the mddev to avoid
2014                  * a deadlock.  We have already changed rdev->size, and if
2015                  * we have to change it back, we will have the lock again.
2016                  */
2017                 mddev_t *mddev;
2018                 int overlap = 0;
2019                 struct list_head *tmp, *tmp2;
2020
2021                 mddev_unlock(my_mddev);
2022                 for_each_mddev(mddev, tmp) {
2023                         mdk_rdev_t *rdev2;
2024
2025                         mddev_lock(mddev);
2026                         rdev_for_each(rdev2, tmp2, mddev)
2027                                 if (test_bit(AllReserved, &rdev2->flags) ||
2028                                     (rdev->bdev == rdev2->bdev &&
2029                                      rdev != rdev2 &&
2030                                      overlaps(rdev->data_offset, rdev->size,
2031                                             rdev2->data_offset, rdev2->size))) {
2032                                         overlap = 1;
2033                                         break;
2034                                 }
2035                         mddev_unlock(mddev);
2036                         if (overlap) {
2037                                 mddev_put(mddev);
2038                                 break;
2039                         }
2040                 }
2041                 mddev_lock(my_mddev);
2042                 if (overlap) {
2043                         /* Someone else could have slipped in a size
2044                          * change here, but doing so is just silly.
2045                          * We put oldsize back because we *know* it is
2046                          * safe, and trust userspace not to race with
2047                          * itself
2048                          */
2049                         rdev->size = oldsize;
2050                         return -EBUSY;
2051                 }
2052         }
2053         if (size < my_mddev->size || my_mddev->size == 0)
2054                 my_mddev->size = size;
2055         return len;
2056 }
2057
2058 static struct rdev_sysfs_entry rdev_size =
2059 __ATTR(size, S_IRUGO|S_IWUSR, rdev_size_show, rdev_size_store);
2060
2061 static struct attribute *rdev_default_attrs[] = {
2062         &rdev_state.attr,
2063         &rdev_super.attr,
2064         &rdev_errors.attr,
2065         &rdev_slot.attr,
2066         &rdev_offset.attr,
2067         &rdev_size.attr,
2068         NULL,
2069 };
2070 static ssize_t
2071 rdev_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
2072 {
2073         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
2074         mdk_rdev_t *rdev = container_of(kobj, mdk_rdev_t, kobj);
2075         mddev_t *mddev = rdev->mddev;
2076         ssize_t rv;
2077
2078         if (!entry->show)
2079                 return -EIO;
2080
2081         rv = mddev ? mddev_lock(mddev) : -EBUSY;
2082         if (!rv) {
2083                 if (rdev->mddev == NULL)
2084                         rv = -EBUSY;
2085                 else
2086                         rv = entry->show(rdev, page);
2087                 mddev_unlock(mddev);
2088         }
2089         return rv;
2090 }
2091
2092 static ssize_t
2093 rdev_attr_store(struct kobject *kobj, struct attribute *attr,
2094               const char *page, size_t length)
2095 {
2096         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
2097         mdk_rdev_t *rdev = container_of(kobj, mdk_rdev_t, kobj);
2098         ssize_t rv;
2099         mddev_t *mddev = rdev->mddev;
2100
2101         if (!entry->store)
2102                 return -EIO;
2103         if (!capable(CAP_SYS_ADMIN))
2104                 return -EACCES;
2105         rv = mddev ? mddev_lock(mddev): -EBUSY;
2106         if (!rv) {
2107                 if (rdev->mddev == NULL)
2108                         rv = -EBUSY;
2109                 else
2110                         rv = entry->store(rdev, page, length);
2111                 mddev_unlock(rdev->mddev);
2112         }
2113         return rv;
2114 }
2115
2116 static void rdev_free(struct kobject *ko)
2117 {
2118         mdk_rdev_t *rdev = container_of(ko, mdk_rdev_t, kobj);
2119         kfree(rdev);
2120 }
2121 static struct sysfs_ops rdev_sysfs_ops = {
2122         .show           = rdev_attr_show,
2123         .store          = rdev_attr_store,
2124 };
2125 static struct kobj_type rdev_ktype = {
2126         .release        = rdev_free,
2127         .sysfs_ops      = &rdev_sysfs_ops,
2128         .default_attrs  = rdev_default_attrs,
2129 };
2130
2131 /*
2132  * Import a device. If 'super_format' >= 0, then sanity check the superblock
2133  *
2134  * mark the device faulty if:
2135  *
2136  *   - the device is nonexistent (zero size)
2137  *   - the device has no valid superblock
2138  *
2139  * a faulty rdev _never_ has rdev->sb set.
2140  */
2141 static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_minor)
2142 {
2143         char b[BDEVNAME_SIZE];
2144         int err;
2145         mdk_rdev_t *rdev;
2146         sector_t size;
2147
2148         rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
2149         if (!rdev) {
2150                 printk(KERN_ERR "md: could not alloc mem for new device!\n");
2151                 return ERR_PTR(-ENOMEM);
2152         }
2153
2154         if ((err = alloc_disk_sb(rdev)))
2155                 goto abort_free;
2156
2157         err = lock_rdev(rdev, newdev, super_format == -2);
2158         if (err)
2159                 goto abort_free;
2160
2161         kobject_init(&rdev->kobj, &rdev_ktype);
2162
2163         rdev->desc_nr = -1;
2164         rdev->saved_raid_disk = -1;
2165         rdev->raid_disk = -1;
2166         rdev->flags = 0;
2167         rdev->data_offset = 0;
2168         rdev->sb_events = 0;
2169         atomic_set(&rdev->nr_pending, 0);
2170         atomic_set(&rdev->read_errors, 0);
2171         atomic_set(&rdev->corrected_errors, 0);
2172
2173         size = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
2174         if (!size) {
2175                 printk(KERN_WARNING
2176                         "md: %s has zero or unknown size, marking faulty!\n",
2177                         bdevname(rdev->bdev,b));
2178                 err = -EINVAL;
2179                 goto abort_free;
2180         }
2181
2182         if (super_format >= 0) {
2183                 err = super_types[super_format].
2184                         load_super(rdev, NULL, super_minor);
2185                 if (err == -EINVAL) {
2186                         printk(KERN_WARNING
2187                                 "md: %s does not have a valid v%d.%d "
2188                                "superblock, not importing!\n",
2189                                 bdevname(rdev->bdev,b),
2190                                super_format, super_minor);
2191                         goto abort_free;
2192                 }
2193                 if (err < 0) {
2194                         printk(KERN_WARNING
2195                                 "md: could not read %s's sb, not importing!\n",
2196                                 bdevname(rdev->bdev,b));
2197                         goto abort_free;
2198                 }
2199         }
2200         INIT_LIST_HEAD(&rdev->same_set);
2201
2202         return rdev;
2203
2204 abort_free:
2205         if (rdev->sb_page) {
2206                 if (rdev->bdev)
2207                         unlock_rdev(rdev);
2208                 free_disk_sb(rdev);
2209         }
2210         kfree(rdev);
2211         return ERR_PTR(err);
2212 }
2213
2214 /*
2215  * Check a full RAID array for plausibility
2216  */
2217
2218
2219 static void analyze_sbs(mddev_t * mddev)
2220 {
2221         int i;
2222         struct list_head *tmp;
2223         mdk_rdev_t *rdev, *freshest;
2224         char b[BDEVNAME_SIZE];
2225
2226         freshest = NULL;
2227         rdev_for_each(rdev, tmp, mddev)
2228                 switch (super_types[mddev->major_version].
2229                         load_super(rdev, freshest, mddev->minor_version)) {
2230                 case 1:
2231                         freshest = rdev;
2232                         break;
2233                 case 0:
2234                         break;
2235                 default:
2236                         printk( KERN_ERR \
2237                                 "md: fatal superblock inconsistency in %s"
2238                                 " -- removing from array\n",
2239                                 bdevname(rdev->bdev,b));
2240                         kick_rdev_from_array(rdev);
2241                 }
2242
2243
2244         super_types[mddev->major_version].
2245                 validate_super(mddev, freshest);
2246
2247         i = 0;
2248         rdev_for_each(rdev, tmp, mddev) {
2249                 if (rdev != freshest)
2250                         if (super_types[mddev->major_version].
2251                             validate_super(mddev, rdev)) {
2252                                 printk(KERN_WARNING "md: kicking non-fresh %s"
2253                                         " from array!\n",
2254                                         bdevname(rdev->bdev,b));
2255                                 kick_rdev_from_array(rdev);
2256                                 continue;
2257                         }
2258                 if (mddev->level == LEVEL_MULTIPATH) {
2259                         rdev->desc_nr = i++;
2260                         rdev->raid_disk = rdev->desc_nr;
2261                         set_bit(In_sync, &rdev->flags);
2262                 } else if (rdev->raid_disk >= mddev->raid_disks) {
2263                         rdev->raid_disk = -1;
2264                         clear_bit(In_sync, &rdev->flags);
2265                 }
2266         }
2267
2268
2269
2270         if (mddev->recovery_cp != MaxSector &&
2271             mddev->level >= 1)
2272                 printk(KERN_ERR "md: %s: raid array is not clean"
2273                        " -- starting background reconstruction\n",
2274                        mdname(mddev));
2275
2276 }
2277
2278 static ssize_t
2279 safe_delay_show(mddev_t *mddev, char *page)
2280 {
2281         int msec = (mddev->safemode_delay*1000)/HZ;
2282         return sprintf(page, "%d.%03d\n", msec/1000, msec%1000);
2283 }
2284 static ssize_t
2285 safe_delay_store(mddev_t *mddev, const char *cbuf, size_t len)
2286 {
2287         int scale=1;
2288         int dot=0;
2289         int i;
2290         unsigned long msec;
2291         char buf[30];
2292         char *e;
2293         /* remove a period, and count digits after it */
2294         if (len >= sizeof(buf))
2295                 return -EINVAL;
2296         strlcpy(buf, cbuf, len);
2297         buf[len] = 0;
2298         for (i=0; i<len; i++) {
2299                 if (dot) {
2300                         if (isdigit(buf[i])) {
2301                                 buf[i-1] = buf[i];
2302                                 scale *= 10;
2303                         }
2304                         buf[i] = 0;
2305                 } else if (buf[i] == '.') {
2306                         dot=1;
2307                         buf[i] = 0;
2308                 }
2309         }
2310         msec = simple_strtoul(buf, &e, 10);
2311         if (e == buf || (*e && *e != '\n'))
2312                 return -EINVAL;
2313         msec = (msec * 1000) / scale;
2314         if (msec == 0)
2315                 mddev->safemode_delay = 0;
2316         else {
2317                 mddev->safemode_delay = (msec*HZ)/1000;
2318                 if (mddev->safemode_delay == 0)
2319                         mddev->safemode_delay = 1;
2320         }
2321         return len;
2322 }
2323 static struct md_sysfs_entry md_safe_delay =
2324 __ATTR(safe_mode_delay, S_IRUGO|S_IWUSR,safe_delay_show, safe_delay_store);
2325
2326 static ssize_t
2327 level_show(mddev_t *mddev, char *page)
2328 {
2329         struct mdk_personality *p = mddev->pers;
2330         if (p)
2331                 return sprintf(page, "%s\n", p->name);
2332         else if (mddev->clevel[0])
2333                 return sprintf(page, "%s\n", mddev->clevel);
2334         else if (mddev->level != LEVEL_NONE)
2335                 return sprintf(page, "%d\n", mddev->level);
2336         else
2337                 return 0;
2338 }
2339
2340 static ssize_t
2341 level_store(mddev_t *mddev, const char *buf, size_t len)
2342 {
2343         ssize_t rv = len;
2344         if (mddev->pers)
2345                 return -EBUSY;
2346         if (len == 0)
2347                 return 0;
2348         if (len >= sizeof(mddev->clevel))
2349                 return -ENOSPC;
2350         strncpy(mddev->clevel, buf, len);
2351         if (mddev->clevel[len-1] == '\n')
2352                 len--;
2353         mddev->clevel[len] = 0;
2354         mddev->level = LEVEL_NONE;
2355         return rv;
2356 }
2357
2358 static struct md_sysfs_entry md_level =
2359 __ATTR(level, S_IRUGO|S_IWUSR, level_show, level_store);
2360
2361
2362 static ssize_t
2363 layout_show(mddev_t *mddev, char *page)
2364 {
2365         /* just a number, not meaningful for all levels */
2366         if (mddev->reshape_position != MaxSector &&
2367             mddev->layout != mddev->new_layout)
2368                 return sprintf(page, "%d (%d)\n",
2369                                mddev->new_layout, mddev->layout);
2370         return sprintf(page, "%d\n", mddev->layout);
2371 }
2372
2373 static ssize_t
2374 layout_store(mddev_t *mddev, const char *buf, size_t len)
2375 {
2376         char *e;
2377         unsigned long n = simple_strtoul(buf, &e, 10);
2378
2379         if (!*buf || (*e && *e != '\n'))
2380                 return -EINVAL;
2381
2382         if (mddev->pers)
2383                 return -EBUSY;
2384         if (mddev->reshape_position != MaxSector)
2385                 mddev->new_layout = n;
2386         else
2387                 mddev->layout = n;
2388         return len;
2389 }
2390 static struct md_sysfs_entry md_layout =
2391 __ATTR(layout, S_IRUGO|S_IWUSR, layout_show, layout_store);
2392
2393
2394 static ssize_t
2395 raid_disks_show(mddev_t *mddev, char *page)
2396 {
2397         if (mddev->raid_disks == 0)
2398                 return 0;
2399         if (mddev->reshape_position != MaxSector &&
2400             mddev->delta_disks != 0)
2401                 return sprintf(page, "%d (%d)\n", mddev->raid_disks,
2402                                mddev->raid_disks - mddev->delta_disks);
2403         return sprintf(page, "%d\n", mddev->raid_disks);
2404 }
2405
2406 static int update_raid_disks(mddev_t *mddev, int raid_disks);
2407
2408 static ssize_t
2409 raid_disks_store(mddev_t *mddev, const char *buf, size_t len)
2410 {
2411         char *e;
2412         int rv = 0;
2413         unsigned long n = simple_strtoul(buf, &e, 10);
2414
2415         if (!*buf || (*e && *e != '\n'))
2416                 return -EINVAL;
2417
2418         if (mddev->pers)
2419                 rv = update_raid_disks(mddev, n);
2420         else if (mddev->reshape_position != MaxSector) {
2421                 int olddisks = mddev->raid_disks - mddev->delta_disks;
2422                 mddev->delta_disks = n - olddisks;
2423                 mddev->raid_disks = n;
2424         } else
2425                 mddev->raid_disks = n;
2426         return rv ? rv : len;
2427 }
2428 static struct md_sysfs_entry md_raid_disks =
2429 __ATTR(raid_disks, S_IRUGO|S_IWUSR, raid_disks_show, raid_disks_store);
2430
2431 static ssize_t
2432 chunk_size_show(mddev_t *mddev, char *page)
2433 {
2434         if (mddev->reshape_position != MaxSector &&
2435             mddev->chunk_size != mddev->new_chunk)
2436                 return sprintf(page, "%d (%d)\n", mddev->new_chunk,
2437                                mddev->chunk_size);
2438         return sprintf(page, "%d\n", mddev->chunk_size);
2439 }
2440
2441 static ssize_t
2442 chunk_size_store(mddev_t *mddev, const char *buf, size_t len)
2443 {
2444         /* can only set chunk_size if array is not yet active */
2445         char *e;
2446         unsigned long n = simple_strtoul(buf, &e, 10);
2447
2448         if (!*buf || (*e && *e != '\n'))
2449                 return -EINVAL;
2450
2451         if (mddev->pers)
2452                 return -EBUSY;
2453         else if (mddev->reshape_position != MaxSector)
2454                 mddev->new_chunk = n;
2455         else
2456                 mddev->chunk_size = n;
2457         return len;
2458 }
2459 static struct md_sysfs_entry md_chunk_size =
2460 __ATTR(chunk_size, S_IRUGO|S_IWUSR, chunk_size_show, chunk_size_store);
2461
2462 static ssize_t
2463 resync_start_show(mddev_t *mddev, char *page)
2464 {
2465         return sprintf(page, "%llu\n", (unsigned long long)mddev->recovery_cp);
2466 }
2467
2468 static ssize_t
2469 resync_start_store(mddev_t *mddev, const char *buf, size_t len)
2470 {
2471         /* can only set chunk_size if array is not yet active */
2472         char *e;
2473         unsigned long long n = simple_strtoull(buf, &e, 10);
2474
2475         if (mddev->pers)
2476                 return -EBUSY;
2477         if (!*buf || (*e && *e != '\n'))
2478                 return -EINVAL;
2479
2480         mddev->recovery_cp = n;
2481         return len;
2482 }
2483 static struct md_sysfs_entry md_resync_start =
2484 __ATTR(resync_start, S_IRUGO|S_IWUSR, resync_start_show, resync_start_store);
2485
2486 /*
2487  * The array state can be:
2488  *
2489  * clear
2490  *     No devices, no size, no level
2491  *     Equivalent to STOP_ARRAY ioctl
2492  * inactive
2493  *     May have some settings, but array is not active
2494  *        all IO results in error
2495  *     When written, doesn't tear down array, but just stops it
2496  * suspended (not supported yet)
2497  *     All IO requests will block. The array can be reconfigured.
2498  *     Writing this, if accepted, will block until array is quiessent
2499  * readonly
2500  *     no resync can happen.  no superblocks get written.
2501  *     write requests fail
2502  * read-auto
2503  *     like readonly, but behaves like 'clean' on a write request.
2504  *
2505  * clean - no pending writes, but otherwise active.
2506  *     When written to inactive array, starts without resync
2507  *     If a write request arrives then
2508  *       if metadata is known, mark 'dirty' and switch to 'active'.
2509  *       if not known, block and switch to write-pending
2510  *     If written to an active array that has pending writes, then fails.
2511  * active
2512  *     fully active: IO and resync can be happening.
2513  *     When written to inactive array, starts with resync
2514  *
2515  * write-pending
2516  *     clean, but writes are blocked waiting for 'active' to be written.
2517  *
2518  * active-idle
2519  *     like active, but no writes have been seen for a while (100msec).
2520  *
2521  */
2522 enum array_state { clear, inactive, suspended, readonly, read_auto, clean, active,
2523                    write_pending, active_idle, bad_word};
2524 static char *array_states[] = {
2525         "clear", "inactive", "suspended", "readonly", "read-auto", "clean", "active",
2526         "write-pending", "active-idle", NULL };
2527
2528 static int match_word(const char *word, char **list)
2529 {
2530         int n;
2531         for (n=0; list[n]; n++)
2532                 if (cmd_match(word, list[n]))
2533                         break;
2534         return n;
2535 }
2536
2537 static ssize_t
2538 array_state_show(mddev_t *mddev, char *page)
2539 {
2540         enum array_state st = inactive;
2541
2542         if (mddev->pers)
2543                 switch(mddev->ro) {
2544                 case 1:
2545                         st = readonly;
2546                         break;
2547                 case 2:
2548                         st = read_auto;
2549                         break;
2550                 case 0:
2551                         if (mddev->in_sync)
2552                                 st = clean;
2553                         else if (test_bit(MD_CHANGE_CLEAN, &mddev->flags))
2554                                 st = write_pending;
2555                         else if (mddev->safemode)
2556                                 st = active_idle;
2557                         else
2558                                 st = active;
2559                 }
2560         else {
2561                 if (list_empty(&mddev->disks) &&
2562                     mddev->raid_disks == 0 &&
2563                     mddev->size == 0)
2564                         st = clear;
2565                 else
2566                         st = inactive;
2567         }
2568         return sprintf(page, "%s\n", array_states[st]);
2569 }
2570
2571 static int do_md_stop(mddev_t * mddev, int ro);
2572 static int do_md_run(mddev_t * mddev);
2573 static int restart_array(mddev_t *mddev);
2574
2575 static ssize_t
2576 array_state_store(mddev_t *mddev, const char *buf, size_t len)
2577 {
2578         int err = -EINVAL;
2579         enum array_state st = match_word(buf, array_states);
2580         switch(st) {
2581         case bad_word:
2582                 break;
2583         case clear:
2584                 /* stopping an active array */
2585                 if (atomic_read(&mddev->active) > 1)
2586                         return -EBUSY;
2587                 err = do_md_stop(mddev, 0);
2588                 break;
2589         case inactive:
2590                 /* stopping an active array */
2591                 if (mddev->pers) {
2592                         if (atomic_read(&mddev->active) > 1)
2593                                 return -EBUSY;
2594                         err = do_md_stop(mddev, 2);
2595                 } else
2596                         err = 0; /* already inactive */
2597                 break;
2598         case suspended:
2599                 break; /* not supported yet */
2600         case readonly:
2601                 if (mddev->pers)
2602                         err = do_md_stop(mddev, 1);
2603                 else {
2604                         mddev->ro = 1;
2605                         err = do_md_run(mddev);
2606                 }
2607                 break;
2608         case read_auto:
2609                 /* stopping an active array */
2610                 if (mddev->pers) {
2611                         err = do_md_stop(mddev, 1);
2612                         if (err == 0)
2613                                 mddev->ro = 2; /* FIXME mark devices writable */
2614                 } else {
2615                         mddev->ro = 2;
2616                         err = do_md_run(mddev);
2617                 }
2618                 break;
2619         case clean:
2620                 if (mddev->pers) {
2621                         restart_array(mddev);
2622                         spin_lock_irq(&mddev->write_lock);
2623                         if (atomic_read(&mddev->writes_pending) == 0) {
2624                                 if (mddev->in_sync == 0) {
2625                                         mddev->in_sync = 1;
2626                                         if (mddev->persistent)
2627                                                 set_bit(MD_CHANGE_CLEAN,
2628                                                         &mddev->flags);
2629                                 }
2630                                 err = 0;
2631                         } else
2632                                 err = -EBUSY;
2633                         spin_unlock_irq(&mddev->write_lock);
2634                 } else {
2635                         mddev->ro = 0;
2636                         mddev->recovery_cp = MaxSector;
2637                         err = do_md_run(mddev);
2638                 }
2639                 break;
2640         case active:
2641                 if (mddev->pers) {
2642                         restart_array(mddev);
2643                         if (mddev->external)
2644                                 clear_bit(MD_CHANGE_CLEAN, &mddev->flags);
2645                         wake_up(&mddev->sb_wait);
2646                         err = 0;
2647                 } else {
2648                         mddev->ro = 0;
2649                         err = do_md_run(mddev);
2650                 }
2651                 break;
2652         case write_pending:
2653         case active_idle:
2654                 /* these cannot be set */
2655                 break;
2656         }
2657         if (err)
2658                 return err;
2659         else
2660                 return len;
2661 }
2662 static struct md_sysfs_entry md_array_state =
2663 __ATTR(array_state, S_IRUGO|S_IWUSR, array_state_show, array_state_store);
2664
2665 static ssize_t
2666 null_show(mddev_t *mddev, char *page)
2667 {
2668         return -EINVAL;
2669 }
2670
2671 static ssize_t
2672 new_dev_store(mddev_t *mddev, const char *buf, size_t len)
2673 {
2674         /* buf must be %d:%d\n? giving major and minor numbers */
2675         /* The new device is added to the array.
2676          * If the array has a persistent superblock, we read the
2677          * superblock to initialise info and check validity.
2678          * Otherwise, only checking done is that in bind_rdev_to_array,
2679          * which mainly checks size.
2680          */
2681         char *e;
2682         int major = simple_strtoul(buf, &e, 10);
2683         int minor;
2684         dev_t dev;
2685         mdk_rdev_t *rdev;
2686         int err;
2687
2688         if (!*buf || *e != ':' || !e[1] || e[1] == '\n')
2689                 return -EINVAL;
2690         minor = simple_strtoul(e+1, &e, 10);
2691         if (*e && *e != '\n')
2692                 return -EINVAL;
2693         dev = MKDEV(major, minor);
2694         if (major != MAJOR(dev) ||
2695             minor != MINOR(dev))
2696                 return -EOVERFLOW;
2697
2698
2699         if (mddev->persistent) {
2700                 rdev = md_import_device(dev, mddev->major_version,
2701                                         mddev->minor_version);
2702                 if (!IS_ERR(rdev) && !list_empty(&mddev->disks)) {
2703                         mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
2704                                                        mdk_rdev_t, same_set);
2705                         err = super_types[mddev->major_version]
2706                                 .load_super(rdev, rdev0, mddev->minor_version);
2707                         if (err < 0)
2708                                 goto out;
2709                 }
2710         } else if (mddev->external)
2711                 rdev = md_import_device(dev, -2, -1);
2712         else
2713                 rdev = md_import_device(dev, -1, -1);
2714
2715         if (IS_ERR(rdev))
2716                 return PTR_ERR(rdev);
2717         err = bind_rdev_to_array(rdev, mddev);
2718  out:
2719         if (err)
2720                 export_rdev(rdev);
2721         return err ? err : len;
2722 }
2723
2724 static struct md_sysfs_entry md_new_device =
2725 __ATTR(new_dev, S_IWUSR, null_show, new_dev_store);
2726
2727 static ssize_t
2728 bitmap_store(mddev_t *mddev, const char *buf, size_t len)
2729 {
2730         char *end;
2731         unsigned long chunk, end_chunk;
2732
2733         if (!mddev->bitmap)
2734                 goto out;
2735         /* buf should be <chunk> <chunk> ... or <chunk>-<chunk> ... (range) */
2736         while (*buf) {
2737                 chunk = end_chunk = simple_strtoul(buf, &end, 0);
2738                 if (buf == end) break;
2739                 if (*end == '-') { /* range */
2740                         buf = end + 1;
2741                         end_chunk = simple_strtoul(buf, &end, 0);
2742                         if (buf == end) break;
2743                 }
2744                 if (*end && !isspace(*end)) break;
2745                 bitmap_dirty_bits(mddev->bitmap, chunk, end_chunk);
2746                 buf = end;
2747                 while (isspace(*buf)) buf++;
2748         }
2749         bitmap_unplug(mddev->bitmap); /* flush the bits to disk */
2750 out:
2751         return len;
2752 }
2753
2754 static struct md_sysfs_entry md_bitmap =
2755 __ATTR(bitmap_set_bits, S_IWUSR, null_show, bitmap_store);
2756
2757 static ssize_t
2758 size_show(mddev_t *mddev, char *page)
2759 {
2760         return sprintf(page, "%llu\n", (unsigned long long)mddev->size);
2761 }
2762
2763 static int update_size(mddev_t *mddev, unsigned long size);
2764
2765 static ssize_t
2766 size_store(mddev_t *mddev, const char *buf, size_t len)
2767 {
2768         /* If array is inactive, we can reduce the component size, but
2769          * not increase it (except from 0).
2770          * If array is active, we can try an on-line resize
2771          */
2772         char *e;
2773         int err = 0;
2774         unsigned long long size = simple_strtoull(buf, &e, 10);
2775         if (!*buf || *buf == '\n' ||
2776             (*e && *e != '\n'))
2777                 return -EINVAL;
2778
2779         if (mddev->pers) {
2780                 err = update_size(mddev, size);
2781                 md_update_sb(mddev, 1);
2782         } else {
2783                 if (mddev->size == 0 ||
2784                     mddev->size > size)
2785                         mddev->size = size;
2786                 else
2787                         err = -ENOSPC;
2788         }
2789         return err ? err : len;
2790 }
2791
2792 static struct md_sysfs_entry md_size =
2793 __ATTR(component_size, S_IRUGO|S_IWUSR, size_show, size_store);
2794
2795
2796 /* Metdata version.
2797  * This is one of
2798  *   'none' for arrays with no metadata (good luck...)
2799  *   'external' for arrays with externally managed metadata,
2800  * or N.M for internally known formats
2801  */
2802 static ssize_t
2803 metadata_show(mddev_t *mddev, char *page)
2804 {
2805         if (mddev->persistent)
2806                 return sprintf(page, "%d.%d\n",
2807                                mddev->major_version, mddev->minor_version);
2808         else if (mddev->external)
2809                 return sprintf(page, "external:%s\n", mddev->metadata_type);
2810         else
2811                 return sprintf(page, "none\n");
2812 }
2813
2814 static ssize_t
2815 metadata_store(mddev_t *mddev, const char *buf, size_t len)
2816 {
2817         int major, minor;
2818         char *e;
2819         if (!list_empty(&mddev->disks))
2820                 return -EBUSY;
2821
2822         if (cmd_match(buf, "none")) {
2823                 mddev->persistent = 0;
2824                 mddev->external = 0;
2825                 mddev->major_version = 0;
2826                 mddev->minor_version = 90;
2827                 return len;
2828         }
2829         if (strncmp(buf, "external:", 9) == 0) {
2830                 size_t namelen = len-9;
2831                 if (namelen >= sizeof(mddev->metadata_type))
2832                         namelen = sizeof(mddev->metadata_type)-1;
2833                 strncpy(mddev->metadata_type, buf+9, namelen);
2834                 mddev->metadata_type[namelen] = 0;
2835                 if (namelen && mddev->metadata_type[namelen-1] == '\n')
2836                         mddev->metadata_type[--namelen] = 0;
2837                 mddev->persistent = 0;
2838                 mddev->external = 1;
2839                 mddev->major_version = 0;
2840                 mddev->minor_version = 90;
2841                 return len;
2842         }
2843         major = simple_strtoul(buf, &e, 10);
2844         if (e==buf || *e != '.')
2845                 return -EINVAL;
2846         buf = e+1;
2847         minor = simple_strtoul(buf, &e, 10);
2848         if (e==buf || (*e && *e != '\n') )
2849                 return -EINVAL;
2850         if (major >= ARRAY_SIZE(super_types) || super_types[major].name == NULL)
2851                 return -ENOENT;
2852         mddev->major_version = major;
2853         mddev->minor_version = minor;
2854         mddev->persistent = 1;
2855         mddev->external = 0;
2856         return len;
2857 }
2858
2859 static struct md_sysfs_entry md_metadata =
2860 __ATTR(metadata_version, S_IRUGO|S_IWUSR, metadata_show, metadata_store);
2861
2862 static ssize_t
2863 action_show(mddev_t *mddev, char *page)
2864 {
2865         char *type = "idle";
2866         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
2867             (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) {
2868                 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
2869                         type = "reshape";
2870                 else if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
2871                         if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2872                                 type = "resync";
2873                         else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
2874                                 type = "check";
2875                         else
2876                                 type = "repair";
2877                 } else
2878                         type = "recover";
2879         }
2880         return sprintf(page, "%s\n", type);
2881 }
2882
2883 static ssize_t
2884 action_store(mddev_t *mddev, const char *page, size_t len)
2885 {
2886         if (!mddev->pers || !mddev->pers->sync_request)
2887                 return -EINVAL;
2888
2889         if (cmd_match(page, "idle")) {
2890                 if (mddev->sync_thread) {
2891                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2892                         md_unregister_thread(mddev->sync_thread);
2893                         mddev->sync_thread = NULL;
2894                         mddev->recovery = 0;
2895                 }
2896         } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
2897                    test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
2898                 return -EBUSY;
2899         else if (cmd_match(page, "resync") || cmd_match(page, "recover"))
2900                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2901         else if (cmd_match(page, "reshape")) {
2902                 int err;
2903                 if (mddev->pers->start_reshape == NULL)
2904                         return -EINVAL;
2905                 err = mddev->pers->start_reshape(mddev);
2906                 if (err)
2907                         return err;
2908         } else {
2909                 if (cmd_match(page, "check"))
2910                         set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
2911                 else if (!cmd_match(page, "repair"))
2912                         return -EINVAL;
2913                 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
2914                 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
2915         }
2916         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2917         md_wakeup_thread(mddev->thread);
2918         return len;
2919 }
2920
2921 static ssize_t
2922 mismatch_cnt_show(mddev_t *mddev, char *page)
2923 {
2924         return sprintf(page, "%llu\n",
2925                        (unsigned long long) mddev->resync_mismatches);
2926 }
2927
2928 static struct md_sysfs_entry md_scan_mode =
2929 __ATTR(sync_action, S_IRUGO|S_IWUSR, action_show, action_store);
2930
2931
2932 static struct md_sysfs_entry md_mismatches = __ATTR_RO(mismatch_cnt);
2933
2934 static ssize_t
2935 sync_min_show(mddev_t *mddev, char *page)
2936 {
2937         return sprintf(page, "%d (%s)\n", speed_min(mddev),
2938                        mddev->sync_speed_min ? "local": "system");
2939 }
2940
2941 static ssize_t
2942 sync_min_store(mddev_t *mddev, const char *buf, size_t len)
2943 {
2944         int min;
2945         char *e;
2946         if (strncmp(buf, "system", 6)==0) {
2947                 mddev->sync_speed_min = 0;
2948                 return len;
2949         }
2950         min = simple_strtoul(buf, &e, 10);
2951         if (buf == e || (*e && *e != '\n') || min <= 0)
2952                 return -EINVAL;
2953         mddev->sync_speed_min = min;
2954         return len;
2955 }
2956
2957 static struct md_sysfs_entry md_sync_min =
2958 __ATTR(sync_speed_min, S_IRUGO|S_IWUSR, sync_min_show, sync_min_store);
2959
2960 static ssize_t
2961 sync_max_show(mddev_t *mddev, char *page)
2962 {
2963         return sprintf(page, "%d (%s)\n", speed_max(mddev),
2964                        mddev->sync_speed_max ? "local": "system");
2965 }
2966
2967 static ssize_t
2968 sync_max_store(mddev_t *mddev, const char *buf, size_t len)
2969 {
2970         int max;
2971         char *e;
2972         if (strncmp(buf, "system", 6)==0) {
2973                 mddev->sync_speed_max = 0;
2974                 return len;
2975         }
2976         max = simple_strtoul(buf, &e, 10);
2977         if (buf == e || (*e && *e != '\n') || max <= 0)
2978                 return -EINVAL;
2979         mddev->sync_speed_max = max;
2980         return len;
2981 }
2982
2983 static struct md_sysfs_entry md_sync_max =
2984 __ATTR(sync_speed_max, S_IRUGO|S_IWUSR, sync_max_show, sync_max_store);
2985
2986 static ssize_t
2987 degraded_show(mddev_t *mddev, char *page)
2988 {
2989         return sprintf(page, "%d\n", mddev->degraded);
2990 }
2991 static struct md_sysfs_entry md_degraded = __ATTR_RO(degraded);
2992
2993 static ssize_t
2994 sync_speed_show(mddev_t *mddev, char *page)
2995 {
2996         unsigned long resync, dt, db;
2997         resync = (mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active));
2998         dt = ((jiffies - mddev->resync_mark) / HZ);
2999         if (!dt) dt++;
3000         db = resync - (mddev->resync_mark_cnt);
3001         return sprintf(page, "%ld\n", db/dt/2); /* K/sec */
3002 }
3003
3004 static struct md_sysfs_entry md_sync_speed = __ATTR_RO(sync_speed);
3005
3006 static ssize_t
3007 sync_completed_show(mddev_t *mddev, char *page)
3008 {
3009         unsigned long max_blocks, resync;
3010
3011         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
3012                 max_blocks = mddev->resync_max_sectors;
3013         else
3014                 max_blocks = mddev->size << 1;
3015
3016         resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active));
3017         return sprintf(page, "%lu / %lu\n", resync, max_blocks);
3018 }
3019
3020 static struct md_sysfs_entry md_sync_completed = __ATTR_RO(sync_completed);
3021
3022 static ssize_t
3023 max_sync_show(mddev_t *mddev, char *page)
3024 {
3025         if (mddev->resync_max == MaxSector)
3026                 return sprintf(page, "max\n");
3027         else
3028                 return sprintf(page, "%llu\n",
3029                                (unsigned long long)mddev->resync_max);
3030 }
3031 static ssize_t
3032 max_sync_store(mddev_t *mddev, const char *buf, size_t len)
3033 {
3034         if (strncmp(buf, "max", 3) == 0)
3035                 mddev->resync_max = MaxSector;
3036         else {
3037                 char *ep;
3038                 unsigned long long max = simple_strtoull(buf, &ep, 10);
3039                 if (ep == buf || (*ep != 0 && *ep != '\n'))
3040                         return -EINVAL;
3041                 if (max < mddev->resync_max &&
3042                     test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
3043                         return -EBUSY;
3044
3045                 /* Must be a multiple of chunk_size */
3046                 if (mddev->chunk_size) {
3047                         if (max & (sector_t)((mddev->chunk_size>>9)-1))
3048                                 return -EINVAL;
3049                 }
3050                 mddev->resync_max = max;
3051         }
3052         wake_up(&mddev->recovery_wait);
3053         return len;
3054 }
3055
3056 static struct md_sysfs_entry md_max_sync =
3057 __ATTR(sync_max, S_IRUGO|S_IWUSR, max_sync_show, max_sync_store);
3058
3059 static ssize_t
3060 suspend_lo_show(mddev_t *mddev, char *page)
3061 {
3062         return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_lo);
3063 }
3064
3065 static ssize_t
3066 suspend_lo_store(mddev_t *mddev, const char *buf, size_t len)
3067 {
3068         char *e;
3069         unsigned long long new = simple_strtoull(buf, &e, 10);
3070
3071         if (mddev->pers->quiesce == NULL)
3072                 return -EINVAL;
3073         if (buf == e || (*e && *e != '\n'))
3074                 return -EINVAL;
3075         if (new >= mddev->suspend_hi ||
3076             (new > mddev->suspend_lo && new < mddev->suspend_hi)) {
3077                 mddev->suspend_lo = new;
3078                 mddev->pers->quiesce(mddev, 2);
3079                 return len;
3080         } else
3081                 return -EINVAL;
3082 }
3083 static struct md_sysfs_entry md_suspend_lo =
3084 __ATTR(suspend_lo, S_IRUGO|S_IWUSR, suspend_lo_show, suspend_lo_store);
3085
3086
3087 static ssize_t
3088 suspend_hi_show(mddev_t *mddev, char *page)
3089 {
3090         return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_hi);
3091 }
3092
3093 static ssize_t
3094 suspend_hi_store(mddev_t *mddev, const char *buf, size_t len)
3095 {
3096         char *e;
3097         unsigned long long new = simple_strtoull(buf, &e, 10);
3098
3099         if (mddev->pers->quiesce == NULL)
3100                 return -EINVAL;
3101         if (buf == e || (*e && *e != '\n'))
3102                 return -EINVAL;
3103         if ((new <= mddev->suspend_lo && mddev->suspend_lo >= mddev->suspend_hi) ||
3104             (new > mddev->suspend_lo && new > mddev->suspend_hi)) {
3105                 mddev->suspend_hi = new;
3106                 mddev->pers->quiesce(mddev, 1);
3107                 mddev->pers->quiesce(mddev, 0);
3108                 return len;
3109         } else
3110                 return -EINVAL;
3111 }
3112 static struct md_sysfs_entry md_suspend_hi =
3113 __ATTR(suspend_hi, S_IRUGO|S_IWUSR, suspend_hi_show, suspend_hi_store);
3114
3115 static ssize_t
3116 reshape_position_show(mddev_t *mddev, char *page)
3117 {
3118         if (mddev->reshape_position != MaxSector)
3119                 return sprintf(page, "%llu\n",
3120                                (unsigned long long)mddev->reshape_position);
3121         strcpy(page, "none\n");
3122         return 5;
3123 }
3124
3125 static ssize_t
3126 reshape_position_store(mddev_t *mddev, const char *buf, size_t len)
3127 {
3128         char *e;
3129         unsigned long long new = simple_strtoull(buf, &e, 10);
3130         if (mddev->pers)
3131                 return -EBUSY;
3132         if (buf == e || (*e && *e != '\n'))
3133                 return -EINVAL;
3134         mddev->reshape_position = new;
3135         mddev->delta_disks = 0;
3136         mddev->new_level = mddev->level;
3137         mddev->new_layout = mddev->layout;
3138         mddev->new_chunk = mddev->chunk_size;
3139         return len;
3140 }
3141
3142 static struct md_sysfs_entry md_reshape_position =
3143 __ATTR(reshape_position, S_IRUGO|S_IWUSR, reshape_position_show,
3144        reshape_position_store);
3145
3146
3147 static struct attribute *md_default_attrs[] = {
3148         &md_level.attr,
3149         &md_layout.attr,
3150         &md_raid_disks.attr,
3151         &md_chunk_size.attr,
3152         &md_size.attr,
3153         &md_resync_start.attr,
3154         &md_metadata.attr,
3155         &md_new_device.attr,
3156         &md_safe_delay.attr,
3157         &md_array_state.attr,
3158         &md_reshape_position.attr,
3159         NULL,
3160 };
3161
3162 static struct attribute *md_redundancy_attrs[] = {
3163         &md_scan_mode.attr,
3164         &md_mismatches.attr,
3165         &md_sync_min.attr,
3166         &md_sync_max.attr,
3167         &md_sync_speed.attr,
3168         &md_sync_completed.attr,
3169         &md_max_sync.attr,
3170         &md_suspend_lo.attr,
3171         &md_suspend_hi.attr,
3172         &md_bitmap.attr,
3173         &md_degraded.attr,
3174         NULL,
3175 };
3176 static struct attribute_group md_redundancy_group = {
3177         .name = NULL,
3178         .attrs = md_redundancy_attrs,
3179 };
3180
3181
3182 static ssize_t
3183 md_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
3184 {
3185         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
3186         mddev_t *mddev = container_of(kobj, struct mddev_s, kobj);
3187         ssize_t rv;
3188
3189         if (!entry->show)
3190                 return -EIO;
3191         rv = mddev_lock(mddev);
3192         if (!rv) {
3193                 rv = entry->show(mddev, page);
3194                 mddev_unlock(mddev);
3195         }
3196         return rv;
3197 }
3198
3199 static ssize_t
3200 md_attr_store(struct kobject *kobj, struct attribute *attr,
3201               const char *page, size_t length)
3202 {
3203         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
3204         mddev_t *mddev = container_of(kobj, struct mddev_s, kobj);
3205         ssize_t rv;
3206
3207         if (!entry->store)
3208                 return -EIO;
3209         if (!capable(CAP_SYS_ADMIN))
3210                 return -EACCES;
3211         rv = mddev_lock(mddev);
3212         if (!rv) {
3213                 rv = entry->store(mddev, page, length);
3214                 mddev_unlock(mddev);
3215         }
3216         return rv;
3217 }
3218
3219 static void md_free(struct kobject *ko)
3220 {
3221         mddev_t *mddev = container_of(ko, mddev_t, kobj);
3222         kfree(mddev);
3223 }
3224
3225 static struct sysfs_ops md_sysfs_ops = {
3226         .show   = md_attr_show,
3227         .store  = md_attr_store,
3228 };
3229 static struct kobj_type md_ktype = {
3230         .release        = md_free,
3231         .sysfs_ops      = &md_sysfs_ops,
3232         .default_attrs  = md_default_attrs,
3233 };
3234
3235 int mdp_major = 0;
3236
3237 static struct kobject *md_probe(dev_t dev, int *part, void *data)
3238 {
3239         static DEFINE_MUTEX(disks_mutex);
3240         mddev_t *mddev = mddev_find(dev);
3241         struct gendisk *disk;
3242         int partitioned = (MAJOR(dev) != MD_MAJOR);
3243         int shift = partitioned ? MdpMinorShift : 0;
3244         int unit = MINOR(dev) >> shift;
3245         int error;
3246
3247         if (!mddev)
3248                 return NULL;
3249
3250         mutex_lock(&disks_mutex);
3251         if (mddev->gendisk) {
3252                 mutex_unlock(&disks_mutex);
3253                 mddev_put(mddev);
3254                 return NULL;
3255         }
3256         disk = alloc_disk(1 << shift);
3257         if (!disk) {
3258                 mutex_unlock(&disks_mutex);
3259                 mddev_put(mddev);
3260                 return NULL;
3261         }
3262         disk->major = MAJOR(dev);
3263         disk->first_minor = unit << shift;
3264         if (partitioned)
3265                 sprintf(disk->disk_name, "md_d%d", unit);
3266         else
3267                 sprintf(disk->disk_name, "md%d", unit);
3268         disk->fops = &md_fops;
3269         disk->private_data = mddev;
3270         disk->queue = mddev->queue;
3271         add_disk(disk);
3272         mddev->gendisk = disk;
3273         mutex_unlock(&disks_mutex);
3274         error = kobject_init_and_add(&mddev->kobj, &md_ktype, &disk->dev.kobj,
3275                                      "%s", "md");
3276         if (error)
3277                 printk(KERN_WARNING "md: cannot register %s/md - name in use\n",
3278                        disk->disk_name);
3279         else
3280                 kobject_uevent(&mddev->kobj, KOBJ_ADD);
3281         return NULL;
3282 }
3283
3284 static void md_safemode_timeout(unsigned long data)
3285 {
3286         mddev_t *mddev = (mddev_t *) data;
3287
3288         mddev->safemode = 1;
3289         md_wakeup_thread(mddev->thread);
3290 }
3291
3292 static int start_dirty_degraded;
3293
3294 static int do_md_run(mddev_t * mddev)
3295 {
3296         int err;
3297         int chunk_size;
3298         struct list_head *tmp;
3299         mdk_rdev_t *rdev;
3300         struct gendisk *disk;
3301         struct mdk_personality *pers;
3302         char b[BDEVNAME_SIZE];
3303
3304         if (list_empty(&mddev->disks))
3305                 /* cannot run an array with no devices.. */
3306                 return -EINVAL;
3307
3308         if (mddev->pers)
3309                 return -EBUSY;
3310
3311         /*
3312          * Analyze all RAID superblock(s)
3313          */
3314         if (!mddev->raid_disks) {
3315                 if (!mddev->persistent)
3316                         return -EINVAL;
3317                 analyze_sbs(mddev);
3318         }
3319
3320         chunk_size = mddev->chunk_size;
3321
3322         if (chunk_size) {
3323                 if (chunk_size > MAX_CHUNK_SIZE) {
3324                         printk(KERN_ERR "too big chunk_size: %d > %d\n",
3325                                 chunk_size, MAX_CHUNK_SIZE);
3326                         return -EINVAL;
3327                 }
3328                 /*
3329                  * chunk-size has to be a power of 2 and multiples of PAGE_SIZE
3330                  */
3331                 if ( (1 << ffz(~chunk_size)) != chunk_size) {
3332                         printk(KERN_ERR "chunk_size of %d not valid\n", chunk_size);
3333                         return -EINVAL;
3334                 }
3335                 if (chunk_size < PAGE_SIZE) {
3336                         printk(KERN_ERR "too small chunk_size: %d < %ld\n",
3337                                 chunk_size, PAGE_SIZE);
3338                         return -EINVAL;
3339                 }
3340
3341                 /* devices must have minimum size of one chunk */
3342                 rdev_for_each(rdev, tmp, mddev) {
3343                         if (test_bit(Faulty, &rdev->flags))
3344                                 continue;
3345                         if (rdev->size < chunk_size / 1024) {
3346                                 printk(KERN_WARNING
3347                                         "md: Dev %s smaller than chunk_size:"
3348                                         " %lluk < %dk\n",
3349                                         bdevname(rdev->bdev,b),
3350                                         (unsigned long long)rdev->size,
3351                                         chunk_size / 1024);
3352                                 return -EINVAL;
3353                         }
3354                 }
3355         }
3356
3357 #ifdef CONFIG_KMOD
3358         if (mddev->level != LEVEL_NONE)
3359                 request_module("md-level-%d", mddev->level);
3360         else if (mddev->clevel[0])
3361                 request_module("md-%s", mddev->clevel);
3362 #endif
3363
3364         /*
3365          * Drop all container device buffers, from now on
3366          * the only valid external interface is through the md
3367          * device.
3368          */
3369         rdev_for_each(rdev, tmp, mddev) {
3370                 if (test_bit(Faulty, &rdev->flags))
3371                         continue;
3372                 sync_blockdev(rdev->bdev);
3373                 invalidate_bdev(rdev->bdev);
3374
3375                 /* perform some consistency tests on the device.
3376                  * We don't want the data to overlap the metadata,
3377                  * Internal Bitmap issues has handled elsewhere.
3378                  */
3379                 if (rdev->data_offset < rdev->sb_offset) {
3380                         if (mddev->size &&
3381                             rdev->data_offset + mddev->size*2
3382                             > rdev->sb_offset*2) {
3383                                 printk("md: %s: data overlaps metadata\n",
3384                                        mdname(mddev));
3385                                 return -EINVAL;
3386                         }
3387                 } else {
3388                         if (rdev->sb_offset*2 + rdev->sb_size/512
3389                             > rdev->data_offset) {
3390                                 printk("md: %s: metadata overlaps data\n",
3391                                        mdname(mddev));
3392                                 return -EINVAL;
3393                         }
3394                 }
3395         }
3396
3397         md_probe(mddev->unit, NULL, NULL);
3398         disk = mddev->gendisk;
3399         if (!disk)
3400                 return -ENOMEM;
3401
3402         spin_lock(&pers_lock);
3403         pers = find_pers(mddev->level, mddev->clevel);
3404         if (!pers || !try_module_get(pers->owner)) {
3405                 spin_unlock(&pers_lock);
3406                 if (mddev->level != LEVEL_NONE)
3407                         printk(KERN_WARNING "md: personality for level %d is not loaded!\n",
3408                                mddev->level);
3409                 else
3410                         printk(KERN_WARNING "md: personality for level %s is not loaded!\n",
3411                                mddev->clevel);
3412                 return -EINVAL;
3413         }
3414         mddev->pers = pers;
3415         spin_unlock(&pers_lock);
3416         mddev->level = pers->level;
3417         strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
3418
3419         if (mddev->reshape_position != MaxSector &&
3420             pers->start_reshape == NULL) {
3421                 /* This personality cannot handle reshaping... */
3422                 mddev->pers = NULL;
3423                 module_put(pers->owner);
3424                 return -EINVAL;
3425         }
3426
3427         if (pers->sync_request) {
3428                 /* Warn if this is a potentially silly
3429                  * configuration.
3430                  */
3431                 char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
3432                 mdk_rdev_t *rdev2;
3433                 struct list_head *tmp2;
3434                 int warned = 0;
3435                 rdev_for_each(rdev, tmp, mddev) {
3436                         rdev_for_each(rdev2, tmp2, mddev) {
3437                                 if (rdev < rdev2 &&
3438                                     rdev->bdev->bd_contains ==
3439                                     rdev2->bdev->bd_contains) {
3440                                         printk(KERN_WARNING
3441                                                "%s: WARNING: %s appears to be"
3442                                                " on the same physical disk as"
3443                                                " %s.\n",
3444                                                mdname(mddev),
3445                                                bdevname(rdev->bdev,b),
3446                                                bdevname(rdev2->bdev,b2));
3447                                         warned = 1;
3448                                 }
3449                         }
3450                 }
3451                 if (warned)
3452                         printk(KERN_WARNING
3453                                "True protection against single-disk"
3454                                " failure might be compromised.\n");
3455         }
3456
3457         mddev->recovery = 0;
3458         mddev->resync_max_sectors = mddev->size << 1; /* may be over-ridden by personality */
3459         mddev->barriers_work = 1;
3460         mddev->ok_start_degraded = start_dirty_degraded;
3461
3462         if (start_readonly)
3463                 mddev->ro = 2; /* read-only, but switch on first write */
3464
3465         err = mddev->pers->run(mddev);
3466         if (!err && mddev->pers->sync_request) {
3467                 err = bitmap_create(mddev);
3468                 if (err) {
3469                         printk(KERN_ERR "%s: failed to create bitmap (%d)\n",
3470                                mdname(mddev), err);
3471                         mddev->pers->stop(mddev);
3472                 }
3473         }
3474         if (err) {
3475                 printk(KERN_ERR "md: pers->run() failed ...\n");
3476                 module_put(mddev->pers->owner);
3477                 mddev->pers = NULL;
3478                 bitmap_destroy(mddev);
3479                 return err;
3480         }
3481         if (mddev->pers->sync_request) {
3482                 if (sysfs_create_group(&mddev->kobj, &md_redundancy_group))
3483                         printk(KERN_WARNING
3484                                "md: cannot register extra attributes for %s\n",
3485                                mdname(mddev));
3486         } else if (mddev->ro == 2) /* auto-readonly not meaningful */
3487                 mddev->ro = 0;
3488
3489         atomic_set(&mddev->writes_pending,0);
3490         mddev->safemode = 0;
3491         mddev->safemode_timer.function = md_safemode_timeout;
3492         mddev->safemode_timer.data = (unsigned long) mddev;
3493         mddev->safemode_delay = (200 * HZ)/1000 +1; /* 200 msec delay */
3494         mddev->in_sync = 1;
3495
3496         rdev_for_each(rdev, tmp, mddev)
3497                 if (rdev->raid_disk >= 0) {
3498                         char nm[20];
3499                         sprintf(nm, "rd%d", rdev->raid_disk);
3500                         if (sysfs_create_link(&mddev->kobj, &rdev->kobj, nm))
3501                                 printk("md: cannot register %s for %s\n",
3502                                        nm, mdname(mddev));
3503                 }
3504
3505         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3506
3507         if (mddev->flags)
3508                 md_update_sb(mddev, 0);
3509
3510         set_capacity(disk, mddev->array_size<<1);
3511
3512         /* If we call blk_queue_make_request here, it will
3513          * re-initialise max_sectors etc which may have been
3514          * refined inside -> run.  So just set the bits we need to set.
3515          * Most initialisation happended when we called
3516          * blk_queue_make_request(..., md_fail_request)
3517          * earlier.
3518          */
3519         mddev->queue->queuedata = mddev;
3520         mddev->queue->make_request_fn = mddev->pers->make_request;
3521
3522         /* If there is a partially-recovered drive we need to
3523          * start recovery here.  If we leave it to md_check_recovery,
3524          * it will remove the drives and not do the right thing
3525          */
3526         if (mddev->degraded && !mddev->sync_thread) {
3527                 struct list_head *rtmp;
3528                 int spares = 0;
3529                 rdev_for_each(rdev, rtmp, mddev)
3530                         if (rdev->raid_disk >= 0 &&
3531                             !test_bit(In_sync, &rdev->flags) &&
3532                             !test_bit(Faulty, &rdev->flags))
3533                                 /* complete an interrupted recovery */
3534                                 spares++;
3535                 if (spares && mddev->pers->sync_request) {
3536                         mddev->recovery = 0;
3537                         set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
3538                         mddev->sync_thread = md_register_thread(md_do_sync,
3539                                                                 mddev,
3540                                                                 "%s_resync");
3541                         if (!mddev->sync_thread) {
3542                                 printk(KERN_ERR "%s: could not start resync"
3543                                        " thread...\n",
3544                                        mdname(mddev));
3545                                 /* leave the spares where they are, it shouldn't hurt */
3546                                 mddev->recovery = 0;
3547                         }
3548                 }
3549         }
3550         md_wakeup_thread(mddev->thread);
3551         md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
3552
3553         mddev->changed = 1;
3554         md_new_event(mddev);
3555         kobject_uevent(&mddev->gendisk->dev.kobj, KOBJ_CHANGE);
3556         return 0;
3557 }
3558
3559 static int restart_array(mddev_t *mddev)
3560 {
3561         struct gendisk *disk = mddev->gendisk;
3562         int err;
3563
3564         /*
3565          * Complain if it has no devices
3566          */
3567         err = -ENXIO;
3568         if (list_empty(&mddev->disks))
3569                 goto out;
3570
3571         if (mddev->pers) {
3572                 err = -EBUSY;
3573                 if (!mddev->ro)
3574                         goto out;
3575
3576                 mddev->safemode = 0;
3577                 mddev->ro = 0;
3578                 set_disk_ro(disk, 0);
3579
3580                 printk(KERN_INFO "md: %s switched to read-write mode.\n",
3581                         mdname(mddev));
3582                 /*
3583                  * Kick recovery or resync if necessary
3584                  */
3585                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3586                 md_wakeup_thread(mddev->thread);
3587                 md_wakeup_thread(mddev->sync_thread);
3588                 err = 0;
3589         } else
3590                 err = -EINVAL;
3591
3592 out:
3593         return err;
3594 }
3595
3596 /* similar to deny_write_access, but accounts for our holding a reference
3597  * to the file ourselves */
3598 static int deny_bitmap_write_access(struct file * file)
3599 {
3600         struct inode *inode = file->f_mapping->host;
3601
3602         spin_lock(&inode->i_lock);
3603         if (atomic_read(&inode->i_writecount) > 1) {
3604                 spin_unlock(&inode->i_lock);
3605                 return -ETXTBSY;
3606         }
3607         atomic_set(&inode->i_writecount, -1);
3608         spin_unlock(&inode->i_lock);
3609
3610         return 0;
3611 }
3612
3613 static void restore_bitmap_write_access(struct file *file)
3614 {
3615         struct inode *inode = file->f_mapping->host;
3616
3617         spin_lock(&inode->i_lock);
3618         atomic_set(&inode->i_writecount, 1);
3619         spin_unlock(&inode->i_lock);
3620 }
3621
3622 /* mode:
3623  *   0 - completely stop and dis-assemble array
3624  *   1 - switch to readonly
3625  *   2 - stop but do not disassemble array
3626  */
3627 static int do_md_stop(mddev_t * mddev, int mode)
3628 {
3629         int err = 0;
3630         struct gendisk *disk = mddev->gendisk;
3631
3632         if (mddev->pers) {
3633                 if (atomic_read(&mddev->active)>2) {
3634                         printk("md: %s still in use.\n",mdname(mddev));
3635                         return -EBUSY;
3636                 }
3637
3638                 if (mddev->sync_thread) {
3639                         set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3640                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3641                         md_unregister_thread(mddev->sync_thread);
3642                         mddev->sync_thread = NULL;
3643                 }
3644
3645                 del_timer_sync(&mddev->safemode_timer);
3646
3647                 invalidate_partition(disk, 0);
3648
3649                 switch(mode) {
3650                 case 1: /* readonly */
3651                         err  = -ENXIO;
3652                         if (mddev->ro==1)
3653                                 goto out;
3654                         mddev->ro = 1;
3655                         break;
3656                 case 0: /* disassemble */
3657                 case 2: /* stop */
3658                         bitmap_flush(mddev);
3659                         md_super_wait(mddev);
3660                         if (mddev->ro)
3661                                 set_disk_ro(disk, 0);
3662                         blk_queue_make_request(mddev->queue, md_fail_request);
3663                         mddev->pers->stop(mddev);
3664                         mddev->queue->merge_bvec_fn = NULL;
3665                         mddev->queue->unplug_fn = NULL;
3666                         mddev->queue->backing_dev_info.congested_fn = NULL;
3667                         if (mddev->pers->sync_request)
3668                                 sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
3669
3670                         module_put(mddev->pers->owner);
3671                         mddev->pers = NULL;
3672
3673                         set_capacity(disk, 0);
3674                         mddev->changed = 1;
3675
3676                         if (mddev->ro)
3677                                 mddev->ro = 0;
3678                 }
3679                 if (!mddev->in_sync || mddev->flags) {
3680                         /* mark array as shutdown cleanly */
3681                         mddev->in_sync = 1;
3682                         md_update_sb(mddev, 1);
3683                 }
3684                 if (mode == 1)
3685                         set_disk_ro(disk, 1);
3686                 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3687         }
3688
3689         /*
3690          * Free resources if final stop
3691          */
3692         if (mode == 0) {
3693                 mdk_rdev_t *rdev;
3694                 struct list_head *tmp;
3695
3696                 printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
3697
3698                 bitmap_destroy(mddev);
3699                 if (mddev->bitmap_file) {
3700                         restore_bitmap_write_access(mddev->bitmap_file);
3701                         fput(mddev->bitmap_file);
3702                         mddev->bitmap_file = NULL;
3703                 }
3704                 mddev->bitmap_offset = 0;
3705
3706                 rdev_for_each(rdev, tmp, mddev)
3707                         if (rdev->raid_disk >= 0) {
3708                                 char nm[20];
3709                                 sprintf(nm, "rd%d", rdev->raid_disk);
3710                                 sysfs_remove_link(&mddev->kobj, nm);
3711                         }
3712
3713                 /* make sure all md_delayed_delete calls have finished */
3714                 flush_scheduled_work();
3715
3716                 export_array(mddev);
3717
3718                 mddev->array_size = 0;
3719                 mddev->size = 0;
3720                 mddev->raid_disks = 0;
3721                 mddev->recovery_cp = 0;
3722                 mddev->resync_max = MaxSector;
3723                 mddev->reshape_position = MaxSector;
3724                 mddev->external = 0;
3725                 mddev->persistent = 0;
3726
3727         } else if (mddev->pers)
3728                 printk(KERN_INFO "md: %s switched to read-only mode.\n",
3729                         mdname(mddev));
3730         err = 0;
3731         md_new_event(mddev);
3732 out:
3733         return err;
3734 }
3735
3736 #ifndef MODULE
3737 static void autorun_array(mddev_t *mddev)
3738 {
3739         mdk_rdev_t *rdev;
3740         struct list_head *tmp;
3741         int err;
3742
3743         if (list_empty(&mddev->disks))
3744                 return;
3745
3746         printk(KERN_INFO "md: running: ");
3747
3748         rdev_for_each(rdev, tmp, mddev) {
3749                 char b[BDEVNAME_SIZE];
3750                 printk("<%s>", bdevname(rdev->bdev,b));
3751         }
3752         printk("\n");
3753
3754         err = do_md_run (mddev);
3755         if (err) {
3756                 printk(KERN_WARNING "md: do_md_run() returned %d\n", err);
3757                 do_md_stop (mddev, 0);
3758         }
3759 }
3760
3761 /*
3762  * lets try to run arrays based on all disks that have arrived
3763  * until now. (those are in pending_raid_disks)
3764  *
3765  * the method: pick the first pending disk, collect all disks with
3766  * the same UUID, remove all from the pending list and put them into
3767  * the 'same_array' list. Then order this list based on superblock
3768  * update time (freshest comes first), kick out 'old' disks and
3769  * compare superblocks. If everything's fine then run it.
3770  *
3771  * If "unit" is allocated, then bump its reference count
3772  */
3773 static void autorun_devices(int part)
3774 {
3775         struct list_head *tmp;
3776         mdk_rdev_t *rdev0, *rdev;
3777         mddev_t *mddev;
3778         char b[BDEVNAME_SIZE];
3779
3780         printk(KERN_INFO "md: autorun ...\n");
3781         while (!list_empty(&pending_raid_disks)) {
3782                 int unit;
3783                 dev_t dev;
3784                 LIST_HEAD(candidates);
3785                 rdev0 = list_entry(pending_raid_disks.next,
3786                                          mdk_rdev_t, same_set);
3787
3788                 printk(KERN_INFO "md: considering %s ...\n",
3789                         bdevname(rdev0->bdev,b));
3790                 INIT_LIST_HEAD(&candidates);
3791                 rdev_for_each_list(rdev, tmp, pending_raid_disks)
3792                         if (super_90_load(rdev, rdev0, 0) >= 0) {
3793                                 printk(KERN_INFO "md:  adding %s ...\n",
3794                                         bdevname(rdev->bdev,b));
3795                                 list_move(&rdev->same_set, &candidates);
3796                         }
3797                 /*
3798                  * now we have a set of devices, with all of them having
3799                  * mostly sane superblocks. It's time to allocate the
3800                  * mddev.
3801                  */
3802                 if (part) {
3803                         dev = MKDEV(mdp_major,
3804                                     rdev0->preferred_minor << MdpMinorShift);
3805                         unit = MINOR(dev) >> MdpMinorShift;
3806                 } else {
3807                         dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
3808                         unit = MINOR(dev);
3809                 }
3810                 if (rdev0->preferred_minor != unit) {
3811                         printk(KERN_INFO "md: unit number in %s is bad: %d\n",
3812                                bdevname(rdev0->bdev, b), rdev0->preferred_minor);
3813                         break;
3814                 }
3815
3816                 md_probe(dev, NULL, NULL);
3817                 mddev = mddev_find(dev);
3818                 if (!mddev) {
3819                         printk(KERN_ERR
3820                                 "md: cannot allocate memory for md drive.\n");
3821                         break;
3822                 }
3823                 if (mddev_lock(mddev))
3824                         printk(KERN_WARNING "md: %s locked, cannot run\n",
3825                                mdname(mddev));
3826                 else if (mddev->raid_disks || mddev->major_version
3827                          || !list_empty(&mddev->disks)) {
3828                         printk(KERN_WARNING
3829                                 "md: %s already running, cannot run %s\n",
3830                                 mdname(mddev), bdevname(rdev0->bdev,b));
3831                         mddev_unlock(mddev);
3832                 } else {
3833                         printk(KERN_INFO "md: created %s\n", mdname(mddev));
3834                         mddev->persistent = 1;
3835                         rdev_for_each_list(rdev, tmp, candidates) {
3836                                 list_del_init(&rdev->same_set);
3837                                 if (bind_rdev_to_array(rdev, mddev))
3838                                         export_rdev(rdev);
3839                         }
3840                         autorun_array(mddev);
3841                         mddev_unlock(mddev);
3842                 }
3843                 /* on success, candidates will be empty, on error
3844                  * it won't...
3845                  */
3846                 rdev_for_each_list(rdev, tmp, candidates)
3847                         export_rdev(rdev);
3848                 mddev_put(mddev);
3849         }
3850         printk(KERN_INFO "md: ... autorun DONE.\n");
3851 }
3852 #endif /* !MODULE */
3853
3854 static int get_version(void __user * arg)
3855 {
3856         mdu_version_t ver;
3857
3858         ver.major = MD_MAJOR_VERSION;
3859         ver.minor = MD_MINOR_VERSION;
3860         ver.patchlevel = MD_PATCHLEVEL_VERSION;
3861
3862         if (copy_to_user(arg, &ver, sizeof(ver)))
3863                 return -EFAULT;
3864
3865         return 0;
3866 }
3867
3868 static int get_array_info(mddev_t * mddev, void __user * arg)
3869 {
3870         mdu_array_info_t info;
3871         int nr,working,active,failed,spare;
3872         mdk_rdev_t *rdev;
3873         struct list_head *tmp;
3874
3875         nr=working=active=failed=spare=0;
3876         rdev_for_each(rdev, tmp, mddev) {
3877                 nr++;
3878                 if (test_bit(Faulty, &rdev->flags))
3879                         failed++;
3880                 else {
3881                         working++;
3882                         if (test_bit(In_sync, &rdev->flags))
3883                                 active++;
3884                         else
3885                                 spare++;
3886                 }
3887         }
3888
3889         info.major_version = mddev->major_version;
3890         info.minor_version = mddev->minor_version;
3891         info.patch_version = MD_PATCHLEVEL_VERSION;
3892         info.ctime         = mddev->ctime;
3893         info.level         = mddev->level;
3894         info.size          = mddev->size;
3895         if (info.size != mddev->size) /* overflow */
3896                 info.size = -1;
3897         info.nr_disks      = nr;
3898         info.raid_disks    = mddev->raid_disks;
3899         info.md_minor      = mddev->md_minor;
3900         info.not_persistent= !mddev->persistent;
3901
3902         info.utime         = mddev->utime;
3903         info.state         = 0;
3904         if (mddev->in_sync)
3905                 info.state = (1<<MD_SB_CLEAN);
3906         if (mddev->bitmap && mddev->bitmap_offset)
3907                 info.state = (1<<MD_SB_BITMAP_PRESENT);
3908         info.active_disks  = active;
3909         info.working_disks = working;
3910         info.failed_disks  = failed;
3911         info.spare_disks   = spare;
3912
3913         info.layout        = mddev->layout;
3914         info.chunk_size    = mddev->chunk_size;
3915
3916         if (copy_to_user(arg, &info, sizeof(info)))
3917                 return -EFAULT;
3918
3919         return 0;
3920 }
3921
3922 static int get_bitmap_file(mddev_t * mddev, void __user * arg)
3923 {
3924         mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
3925         char *ptr, *buf = NULL;
3926         int err = -ENOMEM;
3927
3928         md_allow_write(mddev);
3929
3930         file = kmalloc(sizeof(*file), GFP_KERNEL);
3931         if (!file)
3932                 goto out;
3933
3934         /* bitmap disabled, zero the first byte and copy out */
3935         if (!mddev->bitmap || !mddev->bitmap->file) {
3936                 file->pathname[0] = '\0';
3937                 goto copy_out;
3938         }
3939
3940         buf = kmalloc(sizeof(file->pathname), GFP_KERNEL);
3941         if (!buf)
3942                 goto out;
3943
3944         ptr = file_path(mddev->bitmap->file, buf, sizeof(file->pathname));
3945         if (!ptr)
3946                 goto out;
3947
3948         strcpy(file->pathname, ptr);
3949
3950 copy_out:
3951         err = 0;
3952         if (copy_to_user(arg, file, sizeof(*file)))
3953                 err = -EFAULT;
3954 out:
3955         kfree(buf);
3956         kfree(file);
3957         return err;
3958 }
3959
3960 static int get_disk_info(mddev_t * mddev, void __user * arg)
3961 {
3962         mdu_disk_info_t info;
3963         unsigned int nr;
3964         mdk_rdev_t *rdev;
3965
3966         if (copy_from_user(&info, arg, sizeof(info)))
3967                 return -EFAULT;
3968
3969         nr = info.number;
3970
3971         rdev = find_rdev_nr(mddev, nr);
3972         if (rdev) {
3973                 info.major = MAJOR(rdev->bdev->bd_dev);
3974                 info.minor = MINOR(rdev->bdev->bd_dev);
3975                 info.raid_disk = rdev->raid_disk;
3976                 info.state = 0;
3977                 if (test_bit(Faulty, &rdev->flags))
3978                         info.state |= (1<<MD_DISK_FAULTY);
3979                 else if (test_bit(In_sync, &rdev->flags)) {
3980                         info.state |= (1<<MD_DISK_ACTIVE);
3981                         info.state |= (1<<MD_DISK_SYNC);
3982                 }
3983                 if (test_bit(WriteMostly, &rdev->flags))
3984                         info.state |= (1<<MD_DISK_WRITEMOSTLY);
3985         } else {
3986                 info.major = info.minor = 0;
3987                 info.raid_disk = -1;
3988                 info.state = (1<<MD_DISK_REMOVED);
3989         }
3990
3991         if (copy_to_user(arg, &info, sizeof(info)))
3992                 return -EFAULT;
3993
3994         return 0;
3995 }
3996
3997 static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
3998 {
3999         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
4000         mdk_rdev_t *rdev;
4001         dev_t dev = MKDEV(info->major,info->minor);
4002
4003         if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
4004                 return -EOVERFLOW;
4005
4006         if (!mddev->raid_disks) {
4007                 int err;
4008                 /* expecting a device which has a superblock */
4009                 rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
4010                 if (IS_ERR(rdev)) {
4011                         printk(KERN_WARNING
4012                                 "md: md_import_device returned %ld\n",
4013                                 PTR_ERR(rdev));
4014                         return PTR_ERR(rdev);
4015                 }
4016                 if (!list_empty(&mddev->disks)) {
4017                         mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
4018                                                         mdk_rdev_t, same_set);
4019                         int err = super_types[mddev->major_version]
4020                                 .load_super(rdev, rdev0, mddev->minor_version);
4021                         if (err < 0) {
4022                                 printk(KERN_WARNING
4023                                         "md: %s has different UUID to %s\n",
4024                                         bdevname(rdev->bdev,b),
4025                                         bdevname(rdev0->bdev,b2));
4026                                 export_rdev(rdev);
4027                                 return -EINVAL;
4028                         }
4029                 }
4030                 err = bind_rdev_to_array(rdev, mddev);
4031                 if (err)
4032                         export_rdev(rdev);
4033                 return err;
4034         }
4035
4036         /*
4037          * add_new_disk can be used once the array is assembled
4038          * to add "hot spares".  They must already have a superblock
4039          * written
4040          */
4041         if (mddev->pers) {
4042                 int err;
4043                 if (!mddev->pers->hot_add_disk) {
4044                         printk(KERN_WARNING
4045                                 "%s: personality does not support diskops!\n",
4046                                mdname(mddev));
4047                         return -EINVAL;
4048                 }
4049                 if (mddev->persistent)
4050                         rdev = md_import_device(dev, mddev->major_version,
4051                                                 mddev->minor_version);
4052                 else
4053                         rdev = md_import_device(dev, -1, -1);
4054                 if (IS_ERR(rdev)) {
4055                         printk(KERN_WARNING
4056                                 "md: md_import_device returned %ld\n",
4057                                 PTR_ERR(rdev));
4058                         return PTR_ERR(rdev);
4059                 }
4060                 /* set save_raid_disk if appropriate */
4061                 if (!mddev->persistent) {
4062                         if (info->state & (1<<MD_DISK_SYNC)  &&
4063                             info->raid_disk < mddev->raid_disks)
4064                                 rdev->raid_disk = info->raid_disk;
4065                         else
4066                                 rdev->raid_disk = -1;
4067                 } else
4068                         super_types[mddev->major_version].
4069                                 validate_super(mddev, rdev);
4070                 rdev->saved_raid_disk = rdev->raid_disk;
4071
4072                 clear_bit(In_sync, &rdev->flags); /* just to be sure */
4073                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
4074                         set_bit(WriteMostly, &rdev->flags);
4075
4076                 rdev->raid_disk = -1;
4077                 err = bind_rdev_to_array(rdev, mddev);
4078                 if (!err && !mddev->pers->hot_remove_disk) {
4079                         /* If there is hot_add_disk but no hot_remove_disk
4080                          * then added disks for geometry changes,
4081                          * and should be added immediately.
4082                          */
4083                         super_types[mddev->major_version].
4084                                 validate_super(mddev, rdev);
4085                         err = mddev->pers->hot_add_disk(mddev, rdev);
4086                         if (err)
4087                                 unbind_rdev_from_array(rdev);
4088                 }
4089                 if (err)
4090                         export_rdev(rdev);
4091
4092                 md_update_sb(mddev, 1);
4093                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4094                 md_wakeup_thread(mddev->thread);
4095                 return err;
4096         }
4097
4098         /* otherwise, add_new_disk is only allowed
4099          * for major_version==0 superblocks
4100          */
4101         if (mddev->major_version != 0) {
4102                 printk(KERN_WARNING "%s: ADD_NEW_DISK not supported\n",
4103                        mdname(mddev));
4104                 return -EINVAL;
4105         }
4106
4107         if (!(info->state & (1<<MD_DISK_FAULTY))) {
4108                 int err;
4109                 rdev = md_import_device (dev, -1, 0);
4110                 if (IS_ERR(rdev)) {
4111                         printk(KERN_WARNING
4112                                 "md: error, md_import_device() returned %ld\n",
4113                                 PTR_ERR(rdev));
4114                         return PTR_ERR(rdev);
4115                 }
4116                 rdev->desc_nr = info->number;
4117                 if (info->raid_disk < mddev->raid_disks)
4118                         rdev->raid_disk = info->raid_disk;
4119                 else
4120                         rdev->raid_disk = -1;
4121
4122                 if (rdev->raid_disk < mddev->raid_disks)
4123                         if (info->state & (1<<MD_DISK_SYNC))
4124                                 set_bit(In_sync, &rdev->flags);
4125
4126                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
4127                         set_bit(WriteMostly, &rdev->flags);
4128
4129                 if (!mddev->persistent) {
4130                         printk(KERN_INFO "md: nonpersistent superblock ...\n");
4131                         rdev->sb_offset = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
4132                 } else
4133                         rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
4134                 rdev->size = calc_dev_size(rdev, mddev->chunk_size);
4135
4136                 err = bind_rdev_to_array(rdev, mddev);
4137                 if (err) {
4138                         export_rdev(rdev);
4139                         return err;
4140                 }
4141         }
4142
4143         return 0;
4144 }
4145
4146 static int hot_remove_disk(mddev_t * mddev, dev_t dev)
4147 {
4148         char b[BDEVNAME_SIZE];
4149         mdk_rdev_t *rdev;
4150
4151         if (!mddev->pers)
4152                 return -ENODEV;
4153
4154         rdev = find_rdev(mddev, dev);
4155         if (!rdev)
4156                 return -ENXIO;
4157
4158         if (rdev->raid_disk >= 0)
4159                 goto busy;
4160
4161         kick_rdev_from_array(rdev);
4162         md_update_sb(mddev, 1);
4163         md_new_event(mddev);
4164
4165         return 0;
4166 busy:
4167         printk(KERN_WARNING "md: cannot remove active disk %s from %s ... \n",
4168                 bdevname(rdev->bdev,b), mdname(mddev));
4169         return -EBUSY;
4170 }
4171
4172 static int hot_add_disk(mddev_t * mddev, dev_t dev)
4173 {
4174         char b[BDEVNAME_SIZE];
4175         int err;
4176         unsigned int size;
4177         mdk_rdev_t *rdev;
4178
4179         if (!mddev->pers)
4180                 return -ENODEV;
4181
4182         if (mddev->major_version != 0) {
4183                 printk(KERN_WARNING "%s: HOT_ADD may only be used with"
4184                         " version-0 superblocks.\n",
4185                         mdname(mddev));
4186                 return -EINVAL;
4187         }
4188         if (!mddev->pers->hot_add_disk) {
4189                 printk(KERN_WARNING
4190                         "%s: personality does not support diskops!\n",
4191                         mdname(mddev));
4192                 return -EINVAL;
4193         }
4194
4195         rdev = md_import_device (dev, -1, 0);
4196         if (IS_ERR(rdev)) {
4197                 printk(KERN_WARNING
4198                         "md: error, md_import_device() returned %ld\n",
4199                         PTR_ERR(rdev));
4200                 return -EINVAL;
4201         }
4202
4203         if (mddev->persistent)
4204                 rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
4205         else
4206                 rdev->sb_offset =
4207                         rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
4208
4209         size = calc_dev_size(rdev, mddev->chunk_size);
4210         rdev->size = size;
4211
4212         if (test_bit(Faulty, &rdev->flags)) {
4213                 printk(KERN_WARNING
4214                         "md: can not hot-add faulty %s disk to %s!\n",
4215                         bdevname(rdev->bdev,b), mdname(mddev));
4216                 err = -EINVAL;
4217                 goto abort_export;
4218         }
4219         clear_bit(In_sync, &rdev->flags);
4220         rdev->desc_nr = -1;
4221         rdev->saved_raid_disk = -1;
4222         err = bind_rdev_to_array(rdev, mddev);
4223         if (err)
4224                 goto abort_export;
4225
4226         /*
4227          * The rest should better be atomic, we can have disk failures
4228          * noticed in interrupt contexts ...
4229          */
4230
4231         if (rdev->desc_nr == mddev->max_disks) {
4232                 printk(KERN_WARNING "%s: can not hot-add to full array!\n",
4233                         mdname(mddev));
4234                 err = -EBUSY;
4235                 goto abort_unbind_export;
4236         }
4237
4238         rdev->raid_disk = -1;
4239
4240         md_update_sb(mddev, 1);
4241
4242         /*
4243          * Kick recovery, maybe this spare has to be added to the
4244          * array immediately.
4245          */
4246         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4247         md_wakeup_thread(mddev->thread);
4248         md_new_event(mddev);
4249         return 0;
4250
4251 abort_unbind_export:
4252         unbind_rdev_from_array(rdev);
4253
4254 abort_export:
4255         export_rdev(rdev);
4256         return err;
4257 }
4258
4259 static int set_bitmap_file(mddev_t *mddev, int fd)
4260 {
4261         int err;
4262
4263         if (mddev->pers) {
4264                 if (!mddev->pers->quiesce)
4265                         return -EBUSY;
4266                 if (mddev->recovery || mddev->sync_thread)
4267                         return -EBUSY;
4268                 /* we should be able to change the bitmap.. */
4269         }
4270
4271
4272         if (fd >= 0) {
4273                 if (mddev->bitmap)
4274                         return -EEXIST; /* cannot add when bitmap is present */
4275                 mddev->bitmap_file = fget(fd);
4276
4277                 if (mddev->bitmap_file == NULL) {
4278                         printk(KERN_ERR "%s: error: failed to get bitmap file\n",
4279                                mdname(mddev));
4280                         return -EBADF;
4281                 }
4282
4283                 err = deny_bitmap_write_access(mddev->bitmap_file);
4284                 if (err) {
4285                         printk(KERN_ERR "%s: error: bitmap file is already in use\n",
4286                                mdname(mddev));
4287                         fput(mddev->bitmap_file);
4288                         mddev->bitmap_file = NULL;
4289                         return err;
4290                 }
4291                 mddev->bitmap_offset = 0; /* file overrides offset */
4292         } else if (mddev->bitmap == NULL)
4293                 return -ENOENT; /* cannot remove what isn't there */
4294         err = 0;
4295         if (mddev->pers) {
4296                 mddev->pers->quiesce(mddev, 1);
4297                 if (fd >= 0)
4298                         err = bitmap_create(mddev);
4299                 if (fd < 0 || err) {
4300                         bitmap_destroy(mddev);
4301                         fd = -1; /* make sure to put the file */
4302                 }
4303                 mddev->pers->quiesce(mddev, 0);
4304         }
4305         if (fd < 0) {
4306                 if (mddev->bitmap_file) {
4307                         restore_bitmap_write_access(mddev->bitmap_file);
4308                         fput(mddev->bitmap_file);
4309                 }
4310                 mddev->bitmap_file = NULL;
4311         }
4312
4313         return err;
4314 }
4315
4316 /*
4317  * set_array_info is used two different ways
4318  * The original usage is when creating a new array.
4319  * In this usage, raid_disks is > 0 and it together with
4320  *  level, size, not_persistent,layout,chunksize determine the
4321  *  shape of the array.
4322  *  This will always create an array with a type-0.90.0 superblock.
4323  * The newer usage is when assembling an array.
4324  *  In this case raid_disks will be 0, and the major_version field is
4325  *  use to determine which style super-blocks are to be found on the devices.
4326  *  The minor and patch _version numbers are also kept incase the
4327  *  super_block handler wishes to interpret them.
4328  */
4329 static int set_array_info(mddev_t * mddev, mdu_array_info_t *info)
4330 {
4331
4332         if (info->raid_disks == 0) {
4333                 /* just setting version number for superblock loading */
4334                 if (info->major_version < 0 ||
4335                     info->major_version >= ARRAY_SIZE(super_types) ||
4336                     super_types[info->major_version].name == NULL) {
4337                         /* maybe try to auto-load a module? */
4338                         printk(KERN_INFO
4339                                 "md: superblock version %d not known\n",
4340                                 info->major_version);
4341                         return -EINVAL;
4342                 }
4343                 mddev->major_version = info->major_version;
4344                 mddev->minor_version = info->minor_version;
4345                 mddev->patch_version = info->patch_version;
4346                 mddev->persistent = !info->not_persistent;
4347                 return 0;
4348         }
4349         mddev->major_version = MD_MAJOR_VERSION;
4350         mddev->minor_version = MD_MINOR_VERSION;
4351         mddev->patch_version = MD_PATCHLEVEL_VERSION;
4352         mddev->ctime         = get_seconds();
4353
4354         mddev->level         = info->level;
4355         mddev->clevel[0]     = 0;
4356         mddev->size          = info->size;
4357         mddev->raid_disks    = info->raid_disks;
4358         /* don't set md_minor, it is determined by which /dev/md* was
4359          * openned
4360          */
4361         if (info->state & (1<<MD_SB_CLEAN))
4362                 mddev->recovery_cp = MaxSector;
4363         else
4364                 mddev->recovery_cp = 0;
4365         mddev->persistent    = ! info->not_persistent;
4366         mddev->external      = 0;
4367
4368         mddev->layout        = info->layout;
4369         mddev->chunk_size    = info->chunk_size;
4370
4371         mddev->max_disks     = MD_SB_DISKS;
4372
4373         if (mddev->persistent)
4374                 mddev->flags         = 0;
4375         set_bit(MD_CHANGE_DEVS, &mddev->flags);
4376
4377         mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
4378         mddev->bitmap_offset = 0;
4379
4380         mddev->reshape_position = MaxSector;
4381
4382         /*
4383          * Generate a 128 bit UUID
4384          */
4385         get_random_bytes(mddev->uuid, 16);
4386
4387         mddev->new_level = mddev->level;
4388         mddev->new_chunk = mddev->chunk_size;
4389         mddev->new_layout = mddev->layout;
4390         mddev->delta_disks = 0;
4391
4392         return 0;
4393 }
4394
4395 static int update_size(mddev_t *mddev, unsigned long size)
4396 {
4397         mdk_rdev_t * rdev;
4398         int rv;
4399         struct list_head *tmp;
4400         int fit = (size == 0);
4401
4402         if (mddev->pers->resize == NULL)
4403                 return -EINVAL;
4404         /* The "size" is the amount of each device that is used.
4405          * This can only make sense for arrays with redundancy.
4406          * linear and raid0 always use whatever space is available
4407          * We can only consider changing the size if no resync
4408          * or reconstruction is happening, and if the new size
4409          * is acceptable. It must fit before the sb_offset or,
4410          * if that is <data_offset, it must fit before the
4411          * size of each device.
4412          * If size is zero, we find the largest size that fits.
4413          */
4414         if (mddev->sync_thread)
4415                 return -EBUSY;
4416         rdev_for_each(rdev, tmp, mddev) {
4417                 sector_t avail;
4418                 avail = rdev->size * 2;
4419
4420                 if (fit && (size == 0 || size > avail/2))
4421                         size = avail/2;
4422                 if (avail < ((sector_t)size << 1))
4423                         return -ENOSPC;
4424         }
4425         rv = mddev->pers->resize(mddev, (sector_t)size *2);
4426         if (!rv) {
4427                 struct block_device *bdev;
4428
4429                 bdev = bdget_disk(mddev->gendisk, 0);
4430                 if (bdev) {
4431                         mutex_lock(&bdev->bd_inode->i_mutex);
4432                         i_size_write(bdev->bd_inode, (loff_t)mddev->array_size << 10);
4433                         mutex_unlock(&bdev->bd_inode->i_mutex);
4434                         bdput(bdev);
4435                 }
4436         }
4437         return rv;
4438 }
4439
4440 static int update_raid_disks(mddev_t *mddev, int raid_disks)
4441 {
4442         int rv;
4443         /* change the number of raid disks */
4444         if (mddev->pers->check_reshape == NULL)
4445                 return -EINVAL;
4446         if (raid_disks <= 0 ||
4447             raid_disks >= mddev->max_disks)
4448                 return -EINVAL;
4449         if (mddev->sync_thread || mddev->reshape_position != MaxSector)
4450                 return -EBUSY;
4451         mddev->delta_disks = raid_disks - mddev->raid_disks;
4452
4453         rv = mddev->pers->check_reshape(mddev);
4454         return rv;
4455 }
4456
4457
4458 /*
4459  * update_array_info is used to change the configuration of an
4460  * on-line array.
4461  * The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
4462  * fields in the info are checked against the array.
4463  * Any differences that cannot be handled will cause an error.
4464  * Normally, only one change can be managed at a time.
4465  */
4466 static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
4467 {
4468         int rv = 0;
4469         int cnt = 0;
4470         int state = 0;
4471
4472         /* calculate expected state,ignoring low bits */
4473         if (mddev->bitmap && mddev->bitmap_offset)
4474                 state |= (1 << MD_SB_BITMAP_PRESENT);
4475
4476         if (mddev->major_version != info->major_version ||
4477             mddev->minor_version != info->minor_version ||
4478 /*          mddev->patch_version != info->patch_version || */
4479             mddev->ctime         != info->ctime         ||
4480             mddev->level         != info->level         ||
4481 /*          mddev->layout        != info->layout        || */
4482             !mddev->persistent   != info->not_persistent||
4483             mddev->chunk_size    != info->chunk_size    ||
4484             /* ignore bottom 8 bits of state, and allow SB_BITMAP_PRESENT to change */
4485             ((state^info->state) & 0xfffffe00)
4486                 )
4487                 return -EINVAL;
4488         /* Check there is only one change */
4489         if (info->size >= 0 && mddev->size != info->size) cnt++;
4490         if (mddev->raid_disks != info->raid_disks) cnt++;
4491         if (mddev->layout != info->layout) cnt++;
4492         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) cnt++;
4493         if (cnt == 0) return 0;
4494         if (cnt > 1) return -EINVAL;
4495
4496         if (mddev->layout != info->layout) {
4497                 /* Change layout
4498                  * we don't need to do anything at the md level, the
4499                  * personality will take care of it all.
4500                  */
4501                 if (mddev->pers->reconfig == NULL)
4502                         return -EINVAL;
4503                 else
4504                         return mddev->pers->reconfig(mddev, info->layout, -1);
4505         }
4506         if (info->size >= 0 && mddev->size != info->size)
4507                 rv = update_size(mddev, info->size);
4508
4509         if (mddev->raid_disks    != info->raid_disks)
4510                 rv = update_raid_disks(mddev, info->raid_disks);
4511
4512         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) {
4513                 if (mddev->pers->quiesce == NULL)
4514                         return -EINVAL;
4515                 if (mddev->recovery || mddev->sync_thread)
4516                         return -EBUSY;
4517                 if (info->state & (1<<MD_SB_BITMAP_PRESENT)) {
4518                         /* add the bitmap */
4519                         if (mddev->bitmap)
4520                                 return -EEXIST;
4521                         if (mddev->default_bitmap_offset == 0)
4522                                 return -EINVAL;
4523                         mddev->bitmap_offset = mddev->default_bitmap_offset;
4524                         mddev->pers->quiesce(mddev, 1);
4525                         rv = bitmap_create(mddev);
4526                         if (rv)
4527                                 bitmap_destroy(mddev);
4528                         mddev->pers->quiesce(mddev, 0);
4529                 } else {
4530                         /* remove the bitmap */
4531                         if (!mddev->bitmap)
4532                                 return -ENOENT;
4533                         if (mddev->bitmap->file)
4534                                 return -EINVAL;
4535                         mddev->pers->quiesce(mddev, 1);
4536                         bitmap_destroy(mddev);
4537                         mddev->pers->quiesce(mddev, 0);
4538                         mddev->bitmap_offset = 0;
4539                 }
4540         }
4541         md_update_sb(mddev, 1);
4542         return rv;
4543 }
4544
4545 static int set_disk_faulty(mddev_t *mddev, dev_t dev)
4546 {
4547         mdk_rdev_t *rdev;
4548
4549         if (mddev->pers == NULL)
4550                 return -ENODEV;
4551
4552         rdev = find_rdev(mddev, dev);
4553         if (!rdev)
4554                 return -ENODEV;
4555
4556         md_error(mddev, rdev);
4557         return 0;
4558 }
4559
4560 static int md_getgeo(struct block_device *bdev, struct hd_geometry *geo)
4561 {
4562         mddev_t *mddev = bdev->bd_disk->private_data;
4563
4564         geo->heads = 2;
4565         geo->sectors = 4;
4566         geo->cylinders = get_capacity(mddev->gendisk) / 8;
4567         return 0;
4568 }
4569
4570 static int md_ioctl(struct inode *inode, struct file *file,
4571                         unsigned int cmd, unsigned long arg)
4572 {
4573         int err = 0;
4574         void __user *argp = (void __user *)arg;
4575         mddev_t *mddev = NULL;
4576
4577         if (!capable(CAP_SYS_ADMIN))
4578                 return -EACCES;
4579
4580         /*
4581          * Commands dealing with the RAID driver but not any
4582          * particular array:
4583          */
4584         switch (cmd)
4585         {
4586                 case RAID_VERSION:
4587                         err = get_version(argp);
4588                         goto done;
4589
4590                 case PRINT_RAID_DEBUG:
4591                         err = 0;
4592                         md_print_devices();
4593                         goto done;
4594
4595 #ifndef MODULE
4596                 case RAID_AUTORUN:
4597                         err = 0;
4598                         autostart_arrays(arg);
4599                         goto done;
4600 #endif
4601                 default:;
4602         }
4603
4604         /*
4605          * Commands creating/starting a new array:
4606          */
4607
4608         mddev = inode->i_bdev->bd_disk->private_data;
4609
4610         if (!mddev) {
4611                 BUG();
4612                 goto abort;
4613         }
4614
4615         err = mddev_lock(mddev);
4616         if (err) {
4617                 printk(KERN_INFO
4618                         "md: ioctl lock interrupted, reason %d, cmd %d\n",
4619                         err, cmd);
4620                 goto abort;
4621         }
4622
4623         switch (cmd)
4624         {
4625                 case SET_ARRAY_INFO:
4626                         {
4627                                 mdu_array_info_t info;
4628                                 if (!arg)
4629                                         memset(&info, 0, sizeof(info));
4630                                 else if (copy_from_user(&info, argp, sizeof(info))) {
4631                                         err = -EFAULT;
4632                                         goto abort_unlock;
4633                                 }
4634                                 if (mddev->pers) {
4635                                         err = update_array_info(mddev, &info);
4636                                         if (err) {
4637                                                 printk(KERN_WARNING "md: couldn't update"
4638                                                        " array info. %d\n", err);
4639                                                 goto abort_unlock;
4640                                         }
4641                                         goto done_unlock;
4642                                 }
4643                                 if (!list_empty(&mddev->disks)) {
4644                                         printk(KERN_WARNING
4645                                                "md: array %s already has disks!\n",
4646                                                mdname(mddev));
4647                                         err = -EBUSY;
4648                                         goto abort_unlock;
4649                                 }
4650                                 if (mddev->raid_disks) {
4651                                         printk(KERN_WARNING
4652                                                "md: array %s already initialised!\n",
4653                                                mdname(mddev));
4654                                         err = -EBUSY;
4655                                         goto abort_unlock;
4656                                 }
4657                                 err = set_array_info(mddev, &info);
4658                                 if (err) {
4659                                         printk(KERN_WARNING "md: couldn't set"
4660                                                " array info. %d\n", err);
4661                                         goto abort_unlock;
4662                                 }
4663                         }
4664                         goto done_unlock;
4665
4666                 default:;
4667         }
4668
4669         /*
4670          * Commands querying/configuring an existing array:
4671          */
4672         /* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
4673          * RUN_ARRAY, and GET_ and SET_BITMAP_FILE are allowed */
4674         if ((!mddev->raid_disks && !mddev->external)
4675             && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
4676             && cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE
4677             && cmd != GET_BITMAP_FILE) {
4678                 err = -ENODEV;
4679                 goto abort_unlock;
4680         }
4681
4682         /*
4683          * Commands even a read-only array can execute:
4684          */
4685         switch (cmd)
4686         {
4687                 case GET_ARRAY_INFO:
4688                         err = get_array_info(mddev, argp);
4689                         goto done_unlock;
4690
4691                 case GET_BITMAP_FILE:
4692                         err = get_bitmap_file(mddev, argp);
4693                         goto done_unlock;
4694
4695                 case GET_DISK_INFO:
4696                         err = get_disk_info(mddev, argp);
4697                         goto done_unlock;
4698
4699                 case RESTART_ARRAY_RW:
4700                         err = restart_array(mddev);
4701                         goto done_unlock;
4702
4703                 case STOP_ARRAY:
4704                         err = do_md_stop (mddev, 0);
4705                         goto done_unlock;
4706
4707                 case STOP_ARRAY_RO:
4708                         err = do_md_stop (mddev, 1);
4709                         goto done_unlock;
4710
4711         /*
4712          * We have a problem here : there is no easy way to give a CHS
4713          * virtual geometry. We currently pretend that we have a 2 heads
4714          * 4 sectors (with a BIG number of cylinders...). This drives
4715          * dosfs just mad... ;-)
4716          */
4717         }
4718
4719         /*
4720          * The remaining ioctls are changing the state of the
4721          * superblock, so we do not allow them on read-only arrays.
4722          * However non-MD ioctls (e.g. get-size) will still come through
4723          * here and hit the 'default' below, so only disallow
4724          * 'md' ioctls, and switch to rw mode if started auto-readonly.
4725          */
4726         if (_IOC_TYPE(cmd) == MD_MAJOR &&
4727             mddev->ro && mddev->pers) {
4728                 if (mddev->ro == 2) {
4729                         mddev->ro = 0;
4730                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4731                 md_wakeup_thread(mddev->thread);
4732
4733                 } else {
4734                         err = -EROFS;
4735                         goto abort_unlock;
4736                 }
4737         }
4738
4739         switch (cmd)
4740         {
4741                 case ADD_NEW_DISK:
4742                 {
4743                         mdu_disk_info_t info;
4744                         if (copy_from_user(&info, argp, sizeof(info)))
4745                                 err = -EFAULT;
4746                         else
4747                                 err = add_new_disk(mddev, &info);
4748                         goto done_unlock;
4749                 }
4750
4751                 case HOT_REMOVE_DISK:
4752                         err = hot_remove_disk(mddev, new_decode_dev(arg));
4753                         goto done_unlock;
4754
4755                 case HOT_ADD_DISK:
4756                         err = hot_add_disk(mddev, new_decode_dev(arg));
4757                         goto done_unlock;
4758
4759                 case SET_DISK_FAULTY:
4760                         err = set_disk_faulty(mddev, new_decode_dev(arg));
4761                         goto done_unlock;
4762
4763                 case RUN_ARRAY:
4764                         err = do_md_run (mddev);
4765                         goto done_unlock;
4766
4767                 case SET_BITMAP_FILE:
4768                         err = set_bitmap_file(mddev, (int)arg);
4769                         goto done_unlock;
4770
4771                 default:
4772                         err = -EINVAL;
4773                         goto abort_unlock;
4774         }
4775
4776 done_unlock:
4777 abort_unlock:
4778         mddev_unlock(mddev);
4779
4780         return err;
4781 done:
4782         if (err)
4783                 MD_BUG();
4784 abort:
4785         return err;
4786 }
4787
4788 static int md_open(struct inode *inode, struct file *file)
4789 {
4790         /*
4791          * Succeed if we can lock the mddev, which confirms that
4792          * it isn't being stopped right now.
4793          */
4794         mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
4795         int err;
4796
4797         if ((err = mutex_lock_interruptible_nested(&mddev->reconfig_mutex, 1)))
4798                 goto out;
4799
4800         err = 0;
4801         mddev_get(mddev);
4802         mddev_unlock(mddev);
4803
4804         check_disk_change(inode->i_bdev);
4805  out:
4806         return err;
4807 }
4808
4809 static int md_release(struct inode *inode, struct file * file)
4810 {
4811         mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
4812
4813         BUG_ON(!mddev);
4814         mddev_put(mddev);
4815
4816         return 0;
4817 }
4818
4819 static int md_media_changed(struct gendisk *disk)
4820 {
4821         mddev_t *mddev = disk->private_data;
4822
4823         return mddev->changed;
4824 }
4825
4826 static int md_revalidate(struct gendisk *disk)
4827 {
4828         mddev_t *mddev = disk->private_data;
4829
4830         mddev->changed = 0;
4831         return 0;
4832 }
4833 static struct block_device_operations md_fops =
4834 {
4835         .owner          = THIS_MODULE,
4836         .open           = md_open,
4837         .release        = md_release,
4838         .ioctl          = md_ioctl,
4839         .getgeo         = md_getgeo,
4840         .media_changed  = md_media_changed,
4841         .revalidate_disk= md_revalidate,
4842 };
4843
4844 static int md_thread(void * arg)
4845 {
4846         mdk_thread_t *thread = arg;
4847
4848         /*
4849          * md_thread is a 'system-thread', it's priority should be very
4850          * high. We avoid resource deadlocks individually in each
4851          * raid personality. (RAID5 does preallocation) We also use RR and
4852          * the very same RT priority as kswapd, thus we will never get
4853          * into a priority inversion deadlock.
4854          *
4855          * we definitely have to have equal or higher priority than
4856          * bdflush, otherwise bdflush will deadlock if there are too
4857          * many dirty RAID5 blocks.
4858          */
4859
4860         allow_signal(SIGKILL);
4861         while (!kthread_should_stop()) {
4862
4863                 /* We need to wait INTERRUPTIBLE so that
4864                  * we don't add to the load-average.
4865                  * That means we need to be sure no signals are
4866                  * pending
4867                  */
4868                 if (signal_pending(current))
4869                         flush_signals(current);
4870
4871                 wait_event_interruptible_timeout
4872                         (thread->wqueue,
4873                          test_bit(THREAD_WAKEUP, &thread->flags)
4874                          || kthread_should_stop(),
4875                          thread->timeout);
4876
4877                 clear_bit(THREAD_WAKEUP, &thread->flags);
4878
4879                 thread->run(thread->mddev);
4880         }
4881
4882         return 0;
4883 }
4884
4885 void md_wakeup_thread(mdk_thread_t *thread)
4886 {
4887         if (thread) {
4888                 dprintk("md: waking up MD thread %s.\n", thread->tsk->comm);
4889                 set_bit(THREAD_WAKEUP, &thread->flags);
4890                 wake_up(&thread->wqueue);
4891         }
4892 }
4893
4894 mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev,
4895                                  const char *name)
4896 {
4897         mdk_thread_t *thread;
4898
4899         thread = kzalloc(sizeof(mdk_thread_t), GFP_KERNEL);
4900         if (!thread)
4901                 return NULL;
4902
4903         init_waitqueue_head(&thread->wqueue);
4904
4905         thread->run = run;
4906         thread->mddev = mddev;
4907         thread->timeout = MAX_SCHEDULE_TIMEOUT;
4908         thread->tsk = kthread_run(md_thread, thread, name, mdname(thread->mddev));
4909         if (IS_ERR(thread->tsk)) {
4910                 kfree(thread);
4911                 return NULL;
4912         }
4913         return thread;
4914 }
4915
4916 void md_unregister_thread(mdk_thread_t *thread)
4917 {
4918         dprintk("interrupting MD-thread pid %d\n", task_pid_nr(thread->tsk));
4919
4920         kthread_stop(thread->tsk);
4921         kfree(thread);
4922 }
4923
4924 void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
4925 {
4926         if (!mddev) {
4927                 MD_BUG();
4928                 return;
4929         }
4930
4931         if (!rdev || test_bit(Faulty, &rdev->flags))
4932                 return;
4933 /*
4934         dprintk("md_error dev:%s, rdev:(%d:%d), (caller: %p,%p,%p,%p).\n",
4935                 mdname(mddev),
4936                 MAJOR(rdev->bdev->bd_dev), MINOR(rdev->bdev->bd_dev),
4937                 __builtin_return_address(0),__builtin_return_address(1),
4938                 __builtin_return_address(2),__builtin_return_address(3));
4939 */
4940         if (!mddev->pers)
4941                 return;
4942         if (!mddev->pers->error_handler)
4943                 return;
4944         mddev->pers->error_handler(mddev,rdev);
4945         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
4946         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4947         md_wakeup_thread(mddev->thread);
4948         md_new_event_inintr(mddev);
4949 }
4950
4951 /* seq_file implementation /proc/mdstat */
4952
4953 static void status_unused(struct seq_file *seq)
4954 {
4955         int i = 0;
4956         mdk_rdev_t *rdev;
4957         struct list_head *tmp;
4958
4959         seq_printf(seq, "unused devices: ");
4960
4961         rdev_for_each_list(rdev, tmp, pending_raid_disks) {
4962                 char b[BDEVNAME_SIZE];
4963                 i++;
4964                 seq_printf(seq, "%s ",
4965                               bdevname(rdev->bdev,b));
4966         }
4967         if (!i)
4968                 seq_printf(seq, "<none>");
4969
4970         seq_printf(seq, "\n");
4971 }
4972
4973
4974 static void status_resync(struct seq_file *seq, mddev_t * mddev)
4975 {
4976         sector_t max_blocks, resync, res;
4977         unsigned long dt, db, rt;
4978         int scale;
4979         unsigned int per_milli;
4980
4981         resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active))/2;
4982
4983         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
4984                 max_blocks = mddev->resync_max_sectors >> 1;
4985         else
4986                 max_blocks = mddev->size;
4987
4988         /*
4989          * Should not happen.
4990          */
4991         if (!max_blocks) {
4992                 MD_BUG();
4993                 return;
4994         }
4995         /* Pick 'scale' such that (resync>>scale)*1000 will fit
4996          * in a sector_t, and (max_blocks>>scale) will fit in a
4997          * u32, as those are the requirements for sector_div.
4998          * Thus 'scale' must be at least 10
4999          */
5000         scale = 10;
5001         if (sizeof(sector_t) > sizeof(unsigned long)) {
5002                 while ( max_blocks/2 > (1ULL<<(scale+32)))
5003                         scale++;
5004         }
5005         res = (resync>>scale)*1000;
5006         sector_div(res, (u32)((max_blocks>>scale)+1));
5007
5008         per_milli = res;
5009         {
5010                 int i, x = per_milli/50, y = 20-x;
5011                 seq_printf(seq, "[");
5012                 for (i = 0; i < x; i++)
5013                         seq_printf(seq, "=");
5014                 seq_printf(seq, ">");
5015                 for (i = 0; i < y; i++)
5016                         seq_printf(seq, ".");
5017                 seq_printf(seq, "] ");
5018         }
5019         seq_printf(seq, " %s =%3u.%u%% (%llu/%llu)",
5020                    (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)?
5021                     "reshape" :
5022                     (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)?
5023                      "check" :
5024                      (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
5025                       "resync" : "recovery"))),
5026                    per_milli/10, per_milli % 10,
5027                    (unsigned long long) resync,
5028                    (unsigned long long) max_blocks);
5029
5030         /*
5031          * We do not want to overflow, so the order of operands and
5032          * the * 100 / 100 trick are important. We do a +1 to be
5033          * safe against division by zero. We only estimate anyway.
5034          *
5035          * dt: time from mark until now
5036          * db: blocks written from mark until now
5037          * rt: remaining time
5038          */
5039         dt = ((jiffies - mddev->resync_mark) / HZ);
5040         if (!dt) dt++;
5041         db = (mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active))
5042                 - mddev->resync_mark_cnt;
5043         rt = (dt * ((unsigned long)(max_blocks-resync) / (db/2/100+1)))/100;
5044
5045         seq_printf(seq, " finish=%lu.%lumin", rt / 60, (rt % 60)/6);
5046
5047         seq_printf(seq, " speed=%ldK/sec", db/2/dt);
5048 }
5049
5050 static void *md_seq_start(struct seq_file *seq, loff_t *pos)
5051 {
5052         struct list_head *tmp;
5053         loff_t l = *pos;
5054         mddev_t *mddev;
5055
5056         if (l >= 0x10000)
5057                 return NULL;
5058         if (!l--)
5059                 /* header */
5060                 return (void*)1;
5061
5062         spin_lock(&all_mddevs_lock);
5063         list_for_each(tmp,&all_mddevs)
5064                 if (!l--) {
5065                         mddev = list_entry(tmp, mddev_t, all_mddevs);
5066                         mddev_get(mddev);
5067                         spin_unlock(&all_mddevs_lock);
5068                         return mddev;
5069                 }
5070         spin_unlock(&all_mddevs_lock);
5071         if (!l--)
5072                 return (void*)2;/* tail */
5073         return NULL;
5074 }
5075
5076 static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
5077 {
5078         struct list_head *tmp;
5079         mddev_t *next_mddev, *mddev = v;
5080
5081         ++*pos;
5082         if (v == (void*)2)
5083                 return NULL;
5084
5085         spin_lock(&all_mddevs_lock);
5086         if (v == (void*)1)
5087                 tmp = all_mddevs.next;
5088         else
5089                 tmp = mddev->all_mddevs.next;
5090         if (tmp != &all_mddevs)
5091                 next_mddev = mddev_get(list_entry(tmp,mddev_t,all_mddevs));
5092         else {
5093                 next_mddev = (void*)2;
5094                 *pos = 0x10000;
5095         }
5096         spin_unlock(&all_mddevs_lock);
5097
5098         if (v != (void*)1)
5099                 mddev_put(mddev);
5100         return next_mddev;
5101
5102 }
5103
5104 static void md_seq_stop(struct seq_file *seq, void *v)
5105 {
5106         mddev_t *mddev = v;
5107
5108         if (mddev && v != (void*)1 && v != (void*)2)
5109                 mddev_put(mddev);
5110 }
5111
5112 struct mdstat_info {
5113         int event;
5114 };
5115
5116 static int md_seq_show(struct seq_file *seq, void *v)
5117 {
5118         mddev_t *mddev = v;
5119         sector_t size;
5120         struct list_head *tmp2;
5121         mdk_rdev_t *rdev;
5122         struct mdstat_info *mi = seq->private;
5123         struct bitmap *bitmap;
5124
5125         if (v == (void*)1) {
5126                 struct mdk_personality *pers;
5127                 seq_printf(seq, "Personalities : ");
5128                 spin_lock(&pers_lock);
5129                 list_for_each_entry(pers, &pers_list, list)
5130                         seq_printf(seq, "[%s] ", pers->name);
5131
5132                 spin_unlock(&pers_lock);
5133                 seq_printf(seq, "\n");
5134                 mi->event = atomic_read(&md_event_count);
5135                 return 0;
5136         }
5137         if (v == (void*)2) {
5138                 status_unused(seq);
5139                 return 0;
5140         }
5141
5142         if (mddev_lock(mddev) < 0)
5143                 return -EINTR;
5144
5145         if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
5146                 seq_printf(seq, "%s : %sactive", mdname(mddev),
5147                                                 mddev->pers ? "" : "in");
5148                 if (mddev->pers) {
5149                         if (mddev->ro==1)
5150                                 seq_printf(seq, " (read-only)");
5151                         if (mddev->ro==2)
5152                                 seq_printf(seq, " (auto-read-only)");
5153                         seq_printf(seq, " %s", mddev->pers->name);
5154                 }
5155
5156                 size = 0;
5157                 rdev_for_each(rdev, tmp2, mddev) {
5158                         char b[BDEVNAME_SIZE];
5159                         seq_printf(seq, " %s[%d]",
5160                                 bdevname(rdev->bdev,b), rdev->desc_nr);
5161                         if (test_bit(WriteMostly, &rdev->flags))
5162                                 seq_printf(seq, "(W)");
5163                         if (test_bit(Faulty, &rdev->flags)) {
5164                                 seq_printf(seq, "(F)");
5165                                 continue;
5166                         } else if (rdev->raid_disk < 0)
5167                                 seq_printf(seq, "(S)"); /* spare */
5168                         size += rdev->size;
5169                 }
5170
5171                 if (!list_empty(&mddev->disks)) {
5172                         if (mddev->pers)
5173                                 seq_printf(seq, "\n      %llu blocks",
5174                                         (unsigned long long)mddev->array_size);
5175                         else
5176                                 seq_printf(seq, "\n      %llu blocks",
5177                                         (unsigned long long)size);
5178                 }
5179                 if (mddev->persistent) {
5180                         if (mddev->major_version != 0 ||
5181                             mddev->minor_version != 90) {
5182                                 seq_printf(seq," super %d.%d",
5183                                            mddev->major_version,
5184                                            mddev->minor_version);
5185                         }
5186                 } else if (mddev->external)
5187                         seq_printf(seq, " super external:%s",
5188                                    mddev->metadata_type);
5189                 else
5190                         seq_printf(seq, " super non-persistent");
5191
5192                 if (mddev->pers) {
5193                         mddev->pers->status (seq, mddev);
5194                         seq_printf(seq, "\n      ");
5195                         if (mddev->pers->sync_request) {
5196                                 if (mddev->curr_resync > 2) {
5197                                         status_resync (seq, mddev);
5198                                         seq_printf(seq, "\n      ");
5199                                 } else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
5200                                         seq_printf(seq, "\tresync=DELAYED\n      ");
5201                                 else if (mddev->recovery_cp < MaxSector)
5202                                         seq_printf(seq, "\tresync=PENDING\n      ");
5203                         }
5204                 } else
5205                         seq_printf(seq, "\n       ");
5206
5207                 if ((bitmap = mddev->bitmap)) {
5208                         unsigned long chunk_kb;
5209                         unsigned long flags;
5210                         spin_lock_irqsave(&bitmap->lock, flags);
5211                         chunk_kb = bitmap->chunksize >> 10;
5212                         seq_printf(seq, "bitmap: %lu/%lu pages [%luKB], "
5213                                 "%lu%s chunk",
5214                                 bitmap->pages - bitmap->missing_pages,
5215                                 bitmap->pages,
5216                                 (bitmap->pages - bitmap->missing_pages)
5217                                         << (PAGE_SHIFT - 10),
5218                                 chunk_kb ? chunk_kb : bitmap->chunksize,
5219                                 chunk_kb ? "KB" : "B");
5220                         if (bitmap->file) {
5221                                 seq_printf(seq, ", file: ");
5222                                 seq_path(seq, &bitmap->file->f_path, " \t\n");
5223                         }
5224
5225                         seq_printf(seq, "\n");
5226                         spin_unlock_irqrestore(&bitmap->lock, flags);
5227                 }
5228
5229                 seq_printf(seq, "\n");
5230         }
5231         mddev_unlock(mddev);
5232
5233         return 0;
5234 }
5235
5236 static struct seq_operations md_seq_ops = {
5237         .start  = md_seq_start,
5238         .next   = md_seq_next,
5239         .stop   = md_seq_stop,
5240         .show   = md_seq_show,
5241 };
5242
5243 static int md_seq_open(struct inode *inode, struct file *file)
5244 {
5245         int error;
5246         struct mdstat_info *mi = kmalloc(sizeof(*mi), GFP_KERNEL);
5247         if (mi == NULL)
5248                 return -ENOMEM;
5249
5250         error = seq_open(file, &md_seq_ops);
5251         if (error)
5252                 kfree(mi);
5253         else {
5254                 struct seq_file *p = file->private_data;
5255                 p->private = mi;
5256                 mi->event = atomic_read(&md_event_count);
5257         }
5258         return error;
5259 }
5260
5261 static unsigned int mdstat_poll(struct file *filp, poll_table *wait)
5262 {
5263         struct seq_file *m = filp->private_data;
5264         struct mdstat_info *mi = m->private;
5265         int mask;
5266
5267         poll_wait(filp, &md_event_waiters, wait);
5268
5269         /* always allow read */
5270         mask = POLLIN | POLLRDNORM;
5271
5272         if (mi->event != atomic_read(&md_event_count))
5273                 mask |= POLLERR | POLLPRI;
5274         return mask;
5275 }
5276
5277 static const struct file_operations md_seq_fops = {
5278         .owner          = THIS_MODULE,
5279         .open           = md_seq_open,
5280         .read           = seq_read,
5281         .llseek         = seq_lseek,
5282         .release        = seq_release_private,
5283         .poll           = mdstat_poll,
5284 };
5285
5286 int register_md_personality(struct mdk_personality *p)
5287 {
5288         spin_lock(&pers_lock);
5289         list_add_tail(&p->list, &pers_list);
5290         printk(KERN_INFO "md: %s personality registered for level %d\n", p->name, p->level);
5291         spin_unlock(&pers_lock);
5292         return 0;
5293 }
5294
5295 int unregister_md_personality(struct mdk_personality *p)
5296 {
5297         printk(KERN_INFO "md: %s personality unregistered\n", p->name);
5298         spin_lock(&pers_lock);
5299         list_del_init(&p->list);
5300         spin_unlock(&pers_lock);
5301         return 0;
5302 }
5303
5304 static int is_mddev_idle(mddev_t *mddev)
5305 {
5306         mdk_rdev_t * rdev;
5307         struct list_head *tmp;
5308         int idle;
5309         long curr_events;
5310
5311         idle = 1;
5312         rdev_for_each(rdev, tmp, mddev) {
5313                 struct gendisk *disk = rdev->bdev->bd_contains->bd_disk;
5314                 curr_events = disk_stat_read(disk, sectors[0]) +
5315                                 disk_stat_read(disk, sectors[1]) -
5316                                 atomic_read(&disk->sync_io);
5317                 /* sync IO will cause sync_io to increase before the disk_stats
5318                  * as sync_io is counted when a request starts, and
5319                  * disk_stats is counted when it completes.
5320                  * So resync activity will cause curr_events to be smaller than
5321                  * when there was no such activity.
5322                  * non-sync IO will cause disk_stat to increase without
5323                  * increasing sync_io so curr_events will (eventually)
5324                  * be larger than it was before.  Once it becomes
5325                  * substantially larger, the test below will cause
5326                  * the array to appear non-idle, and resync will slow
5327                  * down.
5328                  * If there is a lot of outstanding resync activity when
5329                  * we set last_event to curr_events, then all that activity
5330                  * completing might cause the array to appear non-idle
5331                  * and resync will be slowed down even though there might
5332                  * not have been non-resync activity.  This will only
5333                  * happen once though.  'last_events' will soon reflect
5334                  * the state where there is little or no outstanding
5335                  * resync requests, and further resync activity will
5336                  * always make curr_events less than last_events.
5337                  *
5338                  */
5339                 if (curr_events - rdev->last_events > 4096) {
5340                         rdev->last_events = curr_events;
5341                         idle = 0;
5342                 }
5343         }
5344         return idle;
5345 }
5346
5347 void md_done_sync(mddev_t *mddev, int blocks, int ok)
5348 {
5349         /* another "blocks" (512byte) blocks have been synced */
5350         atomic_sub(blocks, &mddev->recovery_active);
5351         wake_up(&mddev->recovery_wait);
5352         if (!ok) {
5353                 set_bit(MD_RECOVERY_ERR, &mddev->recovery);
5354                 md_wakeup_thread(mddev->thread);
5355                 // stop recovery, signal do_sync ....
5356         }
5357 }
5358
5359
5360 /* md_write_start(mddev, bi)
5361  * If we need to update some array metadata (e.g. 'active' flag
5362  * in superblock) before writing, schedule a superblock update
5363  * and wait for it to complete.
5364  */
5365 void md_write_start(mddev_t *mddev, struct bio *bi)
5366 {
5367         if (bio_data_dir(bi) != WRITE)
5368                 return;
5369
5370         BUG_ON(mddev->ro == 1);
5371         if (mddev->ro == 2) {
5372                 /* need to switch to read/write */
5373                 mddev->ro = 0;
5374                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5375                 md_wakeup_thread(mddev->thread);
5376                 md_wakeup_thread(mddev->sync_thread);
5377         }
5378         atomic_inc(&mddev->writes_pending);
5379         if (mddev->in_sync) {
5380                 spin_lock_irq(&mddev->write_lock);
5381                 if (mddev->in_sync) {
5382                         mddev->in_sync = 0;
5383                         set_bit(MD_CHANGE_CLEAN, &mddev->flags);
5384                         md_wakeup_thread(mddev->thread);
5385                 }
5386                 spin_unlock_irq(&mddev->write_lock);
5387         }
5388         wait_event(mddev->sb_wait, mddev->flags==0);
5389 }
5390
5391 void md_write_end(mddev_t *mddev)
5392 {
5393         if (atomic_dec_and_test(&mddev->writes_pending)) {
5394                 if (mddev->safemode == 2)
5395                         md_wakeup_thread(mddev->thread);
5396                 else if (mddev->safemode_delay)
5397                         mod_timer(&mddev->safemode_timer, jiffies + mddev->safemode_delay);
5398         }
5399 }
5400
5401 /* md_allow_write(mddev)
5402  * Calling this ensures that the array is marked 'active' so that writes
5403  * may proceed without blocking.  It is important to call this before
5404  * attempting a GFP_KERNEL allocation while holding the mddev lock.
5405  * Must be called with mddev_lock held.
5406  */
5407 void md_allow_write(mddev_t *mddev)
5408 {
5409         if (!mddev->pers)
5410                 return;
5411         if (mddev->ro)
5412                 return;
5413
5414         spin_lock_irq(&mddev->write_lock);
5415         if (mddev->in_sync) {
5416                 mddev->in_sync = 0;
5417                 set_bit(MD_CHANGE_CLEAN, &mddev->flags);
5418                 if (mddev->safemode_delay &&
5419                     mddev->safemode == 0)
5420                         mddev->safemode = 1;
5421                 spin_unlock_irq(&mddev->write_lock);
5422                 md_update_sb(mddev, 0);
5423         } else
5424                 spin_unlock_irq(&mddev->write_lock);
5425 }
5426 EXPORT_SYMBOL_GPL(md_allow_write);
5427
5428 static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
5429
5430 #define SYNC_MARKS      10
5431 #define SYNC_MARK_STEP  (3*HZ)
5432 void md_do_sync(mddev_t *mddev)
5433 {
5434         mddev_t *mddev2;
5435         unsigned int currspeed = 0,
5436                  window;
5437         sector_t max_sectors,j, io_sectors;
5438         unsigned long mark[SYNC_MARKS];
5439         sector_t mark_cnt[SYNC_MARKS];
5440         int last_mark,m;
5441         struct list_head *tmp;
5442         sector_t last_check;
5443         int skipped = 0;
5444         struct list_head *rtmp;
5445         mdk_rdev_t *rdev;
5446         char *desc;
5447
5448         /* just incase thread restarts... */
5449         if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
5450                 return;
5451         if (mddev->ro) /* never try to sync a read-only array */
5452                 return;
5453
5454         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
5455                 if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
5456                         desc = "data-check";
5457                 else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
5458                         desc = "requested-resync";
5459                 else
5460                         desc = "resync";
5461         } else if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
5462                 desc = "reshape";
5463         else
5464                 desc = "recovery";
5465
5466         /* we overload curr_resync somewhat here.
5467          * 0 == not engaged in resync at all
5468          * 2 == checking that there is no conflict with another sync
5469          * 1 == like 2, but have yielded to allow conflicting resync to
5470          *              commense
5471          * other == active in resync - this many blocks
5472          *
5473          * Before starting a resync we must have set curr_resync to
5474          * 2, and then checked that every "conflicting" array has curr_resync
5475          * less than ours.  When we find one that is the same or higher
5476          * we wait on resync_wait.  To avoid deadlock, we reduce curr_resync
5477          * to 1 if we choose to yield (based arbitrarily on address of mddev structure).
5478          * This will mean we have to start checking from the beginning again.
5479          *
5480          */
5481
5482         do {
5483                 mddev->curr_resync = 2;
5484
5485         try_again:
5486                 if (kthread_should_stop()) {
5487                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
5488                         goto skip;
5489                 }
5490                 for_each_mddev(mddev2, tmp) {
5491                         if (mddev2 == mddev)
5492                                 continue;
5493                         if (mddev2->curr_resync &&
5494                             match_mddev_units(mddev,mddev2)) {
5495                                 DEFINE_WAIT(wq);
5496                                 if (mddev < mddev2 && mddev->curr_resync == 2) {
5497                                         /* arbitrarily yield */
5498                                         mddev->curr_resync = 1;
5499                                         wake_up(&resync_wait);
5500                                 }
5501                                 if (mddev > mddev2 && mddev->curr_resync == 1)
5502                                         /* no need to wait here, we can wait the next
5503                                          * time 'round when curr_resync == 2
5504                                          */
5505                                         continue;
5506                                 prepare_to_wait(&resync_wait, &wq, TASK_UNINTERRUPTIBLE);
5507                                 if (!kthread_should_stop() &&
5508                                     mddev2->curr_resync >= mddev->curr_resync) {
5509                                         printk(KERN_INFO "md: delaying %s of %s"
5510                                                " until %s has finished (they"
5511                                                " share one or more physical units)\n",
5512                                                desc, mdname(mddev), mdname(mddev2));
5513                                         mddev_put(mddev2);
5514                                         schedule();
5515                                         finish_wait(&resync_wait, &wq);
5516                                         goto try_again;
5517                                 }
5518                                 finish_wait(&resync_wait, &wq);
5519                         }
5520                 }
5521         } while (mddev->curr_resync < 2);
5522
5523         j = 0;
5524         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
5525                 /* resync follows the size requested by the personality,
5526                  * which defaults to physical size, but can be virtual size
5527                  */
5528                 max_sectors = mddev->resync_max_sectors;
5529                 mddev->resync_mismatches = 0;
5530                 /* we don't use the checkpoint if there's a bitmap */
5531                 if (!mddev->bitmap &&
5532                     !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
5533                         j = mddev->recovery_cp;
5534         } else if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
5535                 max_sectors = mddev->size << 1;
5536         else {
5537                 /* recovery follows the physical size of devices */
5538                 max_sectors = mddev->size << 1;
5539                 j = MaxSector;
5540                 rdev_for_each(rdev, rtmp, mddev)
5541                         if (rdev->raid_disk >= 0 &&
5542                             !test_bit(Faulty, &rdev->flags) &&
5543                             !test_bit(In_sync, &rdev->flags) &&
5544                             rdev->recovery_offset < j)
5545                                 j = rdev->recovery_offset;
5546         }
5547
5548         printk(KERN_INFO "md: %s of RAID array %s\n", desc, mdname(mddev));
5549         printk(KERN_INFO "md: minimum _guaranteed_  speed:"
5550                 " %d KB/sec/disk.\n", speed_min(mddev));
5551         printk(KERN_INFO "md: using maximum available idle IO bandwidth "
5552                "(but not more than %d KB/sec) for %s.\n",
5553                speed_max(mddev), desc);
5554
5555         is_mddev_idle(mddev); /* this also initializes IO event counters */
5556
5557         io_sectors = 0;
5558         for (m = 0; m < SYNC_MARKS; m++) {
5559                 mark[m] = jiffies;
5560                 mark_cnt[m] = io_sectors;
5561         }
5562         last_mark = 0;
5563         mddev->resync_mark = mark[last_mark];
5564         mddev->resync_mark_cnt = mark_cnt[last_mark];
5565
5566         /*
5567          * Tune reconstruction:
5568          */
5569         window = 32*(PAGE_SIZE/512);
5570         printk(KERN_INFO "md: using %dk window, over a total of %llu blocks.\n",
5571                 window/2,(unsigned long long) max_sectors/2);
5572
5573         atomic_set(&mddev->recovery_active, 0);
5574         init_waitqueue_head(&mddev->recovery_wait);
5575         last_check = 0;
5576
5577         if (j>2) {
5578                 printk(KERN_INFO
5579                        "md: resuming %s of %s from checkpoint.\n",
5580                        desc, mdname(mddev));
5581                 mddev->curr_resync = j;
5582         }
5583
5584         while (j < max_sectors) {
5585                 sector_t sectors;
5586
5587                 skipped = 0;
5588                 if (j >= mddev->resync_max) {
5589                         sysfs_notify(&mddev->kobj, NULL, "sync_completed");
5590                         wait_event(mddev->recovery_wait,
5591                                    mddev->resync_max > j
5592                                    || kthread_should_stop());
5593                 }
5594                 if (kthread_should_stop())
5595                         goto interrupted;
5596                 sectors = mddev->pers->sync_request(mddev, j, &skipped,
5597                                                   currspeed < speed_min(mddev));
5598                 if (sectors == 0) {
5599                         set_bit(MD_RECOVERY_ERR, &mddev->recovery);
5600                         goto out;
5601                 }
5602
5603                 if (!skipped) { /* actual IO requested */
5604                         io_sectors += sectors;
5605                         atomic_add(sectors, &mddev->recovery_active);
5606                 }
5607
5608                 j += sectors;
5609                 if (j>1) mddev->curr_resync = j;
5610                 mddev->curr_mark_cnt = io_sectors;
5611                 if (last_check == 0)
5612                         /* this is the earliers that rebuilt will be
5613                          * visible in /proc/mdstat
5614                          */
5615                         md_new_event(mddev);
5616
5617                 if (last_check + window > io_sectors || j == max_sectors)
5618                         continue;
5619
5620                 last_check = io_sectors;
5621
5622                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery) ||
5623                     test_bit(MD_RECOVERY_ERR, &mddev->recovery))
5624                         break;
5625
5626         repeat:
5627                 if (time_after_eq(jiffies, mark[last_mark] + SYNC_MARK_STEP )) {
5628                         /* step marks */
5629                         int next = (last_mark+1) % SYNC_MARKS;
5630
5631                         mddev->resync_mark = mark[next];
5632                         mddev->resync_mark_cnt = mark_cnt[next];
5633                         mark[next] = jiffies;
5634                         mark_cnt[next] = io_sectors - atomic_read(&mddev->recovery_active);
5635                         last_mark = next;
5636                 }
5637
5638
5639                 if (kthread_should_stop())
5640                         goto interrupted;
5641
5642
5643                 /*
5644                  * this loop exits only if either when we are slower than
5645                  * the 'hard' speed limit, or the system was IO-idle for
5646                  * a jiffy.
5647                  * the system might be non-idle CPU-wise, but we only care
5648                  * about not overloading the IO subsystem. (things like an
5649                  * e2fsck being done on the RAID array should execute fast)
5650                  */
5651                 blk_unplug(mddev->queue);
5652                 cond_resched();
5653
5654                 currspeed = ((unsigned long)(io_sectors-mddev->resync_mark_cnt))/2
5655                         /((jiffies-mddev->resync_mark)/HZ +1) +1;
5656
5657                 if (currspeed > speed_min(mddev)) {
5658                         if ((currspeed > speed_max(mddev)) ||
5659                                         !is_mddev_idle(mddev)) {
5660                                 msleep(500);
5661                                 goto repeat;
5662                         }
5663                 }
5664         }
5665         printk(KERN_INFO "md: %s: %s done.\n",mdname(mddev), desc);
5666         /*
5667          * this also signals 'finished resyncing' to md_stop
5668          */
5669  out:
5670         blk_unplug(mddev->queue);
5671
5672         wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
5673
5674         /* tell personality that we are finished */
5675         mddev->pers->sync_request(mddev, max_sectors, &skipped, 1);
5676
5677         if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
5678             !test_bit(MD_RECOVERY_CHECK, &mddev->recovery) &&
5679             mddev->curr_resync > 2) {
5680                 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
5681                         if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
5682                                 if (mddev->curr_resync >= mddev->recovery_cp) {
5683                                         printk(KERN_INFO
5684                                                "md: checkpointing %s of %s.\n",
5685                                                desc, mdname(mddev));
5686                                         mddev->recovery_cp = mddev->curr_resync;
5687                                 }
5688                         } else
5689                                 mddev->recovery_cp = MaxSector;
5690                 } else {
5691                         if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery))
5692                                 mddev->curr_resync = MaxSector;
5693                         rdev_for_each(rdev, rtmp, mddev)
5694                                 if (rdev->raid_disk >= 0 &&
5695                                     !test_bit(Faulty, &rdev->flags) &&
5696                                     !test_bit(In_sync, &rdev->flags) &&
5697                                     rdev->recovery_offset < mddev->curr_resync)
5698                                         rdev->recovery_offset = mddev->curr_resync;
5699                 }
5700         }
5701         set_bit(MD_CHANGE_DEVS, &mddev->flags);
5702
5703  skip:
5704         mddev->curr_resync = 0;
5705         mddev->resync_max = MaxSector;
5706         sysfs_notify(&mddev->kobj, NULL, "sync_completed");
5707         wake_up(&resync_wait);
5708         set_bit(MD_RECOVERY_DONE, &mddev->recovery);
5709         md_wakeup_thread(mddev->thread);
5710         return;
5711
5712  interrupted:
5713         /*
5714          * got a signal, exit.
5715          */
5716         printk(KERN_INFO
5717                "md: md_do_sync() got signal ... exiting\n");
5718         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
5719         goto out;
5720
5721 }
5722 EXPORT_SYMBOL_GPL(md_do_sync);
5723
5724
5725 static int remove_and_add_spares(mddev_t *mddev)
5726 {
5727         mdk_rdev_t *rdev;
5728         struct list_head *rtmp;
5729         int spares = 0;
5730
5731         rdev_for_each(rdev, rtmp, mddev)
5732                 if (rdev->raid_disk >= 0 &&
5733                     !mddev->external &&
5734                     (test_bit(Faulty, &rdev->flags) ||
5735                      ! test_bit(In_sync, &rdev->flags)) &&
5736                     atomic_read(&rdev->nr_pending)==0) {
5737                         if (mddev->pers->hot_remove_disk(
5738                                     mddev, rdev->raid_disk)==0) {
5739                                 char nm[20];
5740                                 sprintf(nm,"rd%d", rdev->raid_disk);
5741                                 sysfs_remove_link(&mddev->kobj, nm);
5742                                 rdev->raid_disk = -1;
5743                         }
5744                 }
5745
5746         if (mddev->degraded) {
5747                 rdev_for_each(rdev, rtmp, mddev)
5748                         if (rdev->raid_disk < 0
5749                             && !test_bit(Faulty, &rdev->flags)) {
5750                                 rdev->recovery_offset = 0;
5751                                 if (mddev->pers->hot_add_disk(mddev,rdev)) {
5752                                         char nm[20];
5753                                         sprintf(nm, "rd%d", rdev->raid_disk);
5754                                         if (sysfs_create_link(&mddev->kobj,
5755                                                               &rdev->kobj, nm))
5756                                                 printk(KERN_WARNING
5757                                                        "md: cannot register "
5758                                                        "%s for %s\n",
5759                                                        nm, mdname(mddev));
5760                                         spares++;
5761                                         md_new_event(mddev);
5762                                 } else
5763                                         break;
5764                         }
5765         }
5766         return spares;
5767 }
5768 /*
5769  * This routine is regularly called by all per-raid-array threads to
5770  * deal with generic issues like resync and super-block update.
5771  * Raid personalities that don't have a thread (linear/raid0) do not
5772  * need this as they never do any recovery or update the superblock.
5773  *
5774  * It does not do any resync itself, but rather "forks" off other threads
5775  * to do that as needed.
5776  * When it is determined that resync is needed, we set MD_RECOVERY_RUNNING in
5777  * "->recovery" and create a thread at ->sync_thread.
5778  * When the thread finishes it sets MD_RECOVERY_DONE (and might set MD_RECOVERY_ERR)
5779  * and wakeups up this thread which will reap the thread and finish up.
5780  * This thread also removes any faulty devices (with nr_pending == 0).
5781  *
5782  * The overall approach is:
5783  *  1/ if the superblock needs updating, update it.
5784  *  2/ If a recovery thread is running, don't do anything else.
5785  *  3/ If recovery has finished, clean up, possibly marking spares active.
5786  *  4/ If there are any faulty devices, remove them.
5787  *  5/ If array is degraded, try to add spares devices
5788  *  6/ If array has spares or is not in-sync, start a resync thread.
5789  */
5790 void md_check_recovery(mddev_t *mddev)
5791 {
5792         mdk_rdev_t *rdev;
5793         struct list_head *rtmp;
5794
5795
5796         if (mddev->bitmap)
5797                 bitmap_daemon_work(mddev->bitmap);
5798
5799         if (mddev->ro)
5800                 return;
5801
5802         if (signal_pending(current)) {
5803                 if (mddev->pers->sync_request) {
5804                         printk(KERN_INFO "md: %s in immediate safe mode\n",
5805                                mdname(mddev));
5806                         mddev->safemode = 2;
5807                 }
5808                 flush_signals(current);
5809         }
5810
5811         if ( ! (
5812                 (mddev->flags && !mddev->external) ||
5813                 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
5814                 test_bit(MD_RECOVERY_DONE, &mddev->recovery) ||
5815                 (mddev->safemode == 1) ||
5816                 (mddev->safemode == 2 && ! atomic_read(&mddev->writes_pending)
5817                  && !mddev->in_sync && mddev->recovery_cp == MaxSector)
5818                 ))
5819                 return;
5820
5821         if (mddev_trylock(mddev)) {
5822                 int spares = 0;
5823
5824                 spin_lock_irq(&mddev->write_lock);
5825                 if (mddev->safemode && !atomic_read(&mddev->writes_pending) &&
5826                     !mddev->in_sync && mddev->recovery_cp == MaxSector) {
5827                         mddev->in_sync = 1;
5828                         if (mddev->persistent)
5829                                 set_bit(MD_CHANGE_CLEAN, &mddev->flags);
5830                 }
5831                 if (mddev->safemode == 1)
5832                         mddev->safemode = 0;
5833                 spin_unlock_irq(&mddev->write_lock);
5834
5835                 if (mddev->flags)
5836                         md_update_sb(mddev, 0);
5837
5838
5839                 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
5840                     !test_bit(MD_RECOVERY_DONE, &mddev->recovery)) {
5841                         /* resync/recovery still happening */
5842                         clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5843                         goto unlock;
5844                 }
5845                 if (mddev->sync_thread) {
5846                         /* resync has finished, collect result */
5847                         md_unregister_thread(mddev->sync_thread);
5848                         mddev->sync_thread = NULL;
5849                         if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
5850                             !test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
5851                                 /* success...*/
5852                                 /* activate any spares */
5853                                 mddev->pers->spare_active(mddev);
5854                         }
5855                         md_update_sb(mddev, 1);
5856
5857                         /* if array is no-longer degraded, then any saved_raid_disk
5858                          * information must be scrapped
5859                          */
5860                         if (!mddev->degraded)
5861                                 rdev_for_each(rdev, rtmp, mddev)
5862                                         rdev->saved_raid_disk = -1;
5863
5864                         mddev->recovery = 0;
5865                         /* flag recovery needed just to double check */
5866                         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5867                         md_new_event(mddev);
5868                         goto unlock;
5869                 }
5870                 /* Clear some bits that don't mean anything, but
5871                  * might be left set
5872                  */
5873                 clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5874                 clear_bit(MD_RECOVERY_ERR, &mddev->recovery);
5875                 clear_bit(MD_RECOVERY_INTR, &mddev->recovery);
5876                 clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
5877
5878                 if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
5879                         goto unlock;
5880                 /* no recovery is running.
5881                  * remove any failed drives, then
5882                  * add spares if possible.
5883                  * Spare are also removed and re-added, to allow
5884                  * the personality to fail the re-add.
5885                  */
5886
5887                 if (mddev->reshape_position != MaxSector) {
5888                         if (mddev->pers->check_reshape(mddev) != 0)
5889                                 /* Cannot proceed */
5890                                 goto unlock;
5891                         set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
5892                 } else if ((spares = remove_and_add_spares(mddev))) {
5893                         clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
5894                         clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
5895                 } else if (mddev->recovery_cp < MaxSector) {
5896                         set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
5897                 } else if (!test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
5898                         /* nothing to be done ... */
5899                         goto unlock;
5900
5901                 if (mddev->pers->sync_request) {
5902                         set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
5903                         if (spares && mddev->bitmap && ! mddev->bitmap->file) {
5904                                 /* We are adding a device or devices to an array
5905                                  * which has the bitmap stored on all devices.
5906                                  * So make sure all bitmap pages get written
5907                                  */
5908                                 bitmap_write_all(mddev->bitmap);
5909                         }
5910                         mddev->sync_thread = md_register_thread(md_do_sync,
5911                                                                 mddev,
5912                                                                 "%s_resync");
5913                         if (!mddev->sync_thread) {
5914                                 printk(KERN_ERR "%s: could not start resync"
5915                                         " thread...\n",
5916                                         mdname(mddev));
5917                                 /* leave the spares where they are, it shouldn't hurt */
5918                                 mddev->recovery = 0;
5919                         } else
5920                                 md_wakeup_thread(mddev->sync_thread);
5921                         md_new_event(mddev);
5922                 }
5923         unlock:
5924                 mddev_unlock(mddev);
5925         }
5926 }
5927
5928 static int md_notify_reboot(struct notifier_block *this,
5929                             unsigned long code, void *x)
5930 {
5931         struct list_head *tmp;
5932         mddev_t *mddev;
5933
5934         if ((code == SYS_DOWN) || (code == SYS_HALT) || (code == SYS_POWER_OFF)) {
5935
5936                 printk(KERN_INFO "md: stopping all md devices.\n");
5937
5938                 for_each_mddev(mddev, tmp)
5939                         if (mddev_trylock(mddev)) {
5940                                 do_md_stop (mddev, 1);
5941                                 mddev_unlock(mddev);
5942                         }
5943                 /*
5944                  * certain more exotic SCSI devices are known to be
5945                  * volatile wrt too early system reboots. While the
5946                  * right place to handle this issue is the given
5947                  * driver, we do want to have a safe RAID driver ...
5948                  */
5949                 mdelay(1000*1);
5950         }
5951         return NOTIFY_DONE;
5952 }
5953
5954 static struct notifier_block md_notifier = {
5955         .notifier_call  = md_notify_reboot,
5956         .next           = NULL,
5957         .priority       = INT_MAX, /* before any real devices */
5958 };
5959
5960 static void md_geninit(void)
5961 {
5962         struct proc_dir_entry *p;
5963
5964         dprintk("md: sizeof(mdp_super_t) = %d\n", (int)sizeof(mdp_super_t));
5965
5966         p = create_proc_entry("mdstat", S_IRUGO, NULL);
5967         if (p)
5968                 p->proc_fops = &md_seq_fops;
5969 }
5970
5971 static int __init md_init(void)
5972 {
5973         if (register_blkdev(MAJOR_NR, "md"))
5974                 return -1;
5975         if ((mdp_major=register_blkdev(0, "mdp"))<=0) {
5976                 unregister_blkdev(MAJOR_NR, "md");
5977                 return -1;
5978         }
5979         blk_register_region(MKDEV(MAJOR_NR, 0), 1UL<<MINORBITS, THIS_MODULE,
5980                             md_probe, NULL, NULL);
5981         blk_register_region(MKDEV(mdp_major, 0), 1UL<<MINORBITS, THIS_MODULE,
5982                             md_probe, NULL, NULL);
5983
5984         register_reboot_notifier(&md_notifier);
5985         raid_table_header = register_sysctl_table(raid_root_table);
5986
5987         md_geninit();
5988         return (0);
5989 }
5990
5991
5992 #ifndef MODULE
5993
5994 /*
5995  * Searches all registered partitions for autorun RAID arrays
5996  * at boot time.
5997  */
5998
5999 static LIST_HEAD(all_detected_devices);
6000 struct detected_devices_node {
6001         struct list_head list;
6002         dev_t dev;
6003 };
6004
6005 void md_autodetect_dev(dev_t dev)
6006 {
6007         struct detected_devices_node *node_detected_dev;
6008
6009         node_detected_dev = kzalloc(sizeof(*node_detected_dev), GFP_KERNEL);
6010         if (node_detected_dev) {
6011                 node_detected_dev->dev = dev;
6012                 list_add_tail(&node_detected_dev->list, &all_detected_devices);
6013         } else {
6014                 printk(KERN_CRIT "md: md_autodetect_dev: kzalloc failed"
6015                         ", skipping dev(%d,%d)\n", MAJOR(dev), MINOR(dev));
6016         }
6017 }
6018
6019
6020 static void autostart_arrays(int part)
6021 {
6022         mdk_rdev_t *rdev;
6023         struct detected_devices_node *node_detected_dev;
6024         dev_t dev;
6025         int i_scanned, i_passed;
6026
6027         i_scanned = 0;
6028         i_passed = 0;
6029
6030         printk(KERN_INFO "md: Autodetecting RAID arrays.\n");
6031
6032         while (!list_empty(&all_detected_devices) && i_scanned < INT_MAX) {
6033                 i_scanned++;
6034                 node_detected_dev = list_entry(all_detected_devices.next,
6035                                         struct detected_devices_node, list);
6036                 list_del(&node_detected_dev->list);
6037                 dev = node_detected_dev->dev;
6038                 kfree(node_detected_dev);
6039                 rdev = md_import_device(dev,0, 90);
6040                 if (IS_ERR(rdev))
6041                         continue;
6042
6043                 if (test_bit(Faulty, &rdev->flags)) {
6044                         MD_BUG();
6045                         continue;
6046                 }
6047                 set_bit(AutoDetected, &rdev->flags);
6048                 list_add(&rdev->same_set, &pending_raid_disks);
6049                 i_passed++;
6050         }
6051
6052         printk(KERN_INFO "md: Scanned %d and added %d devices.\n",
6053                                                 i_scanned, i_passed);
6054
6055         autorun_devices(part);
6056 }
6057
6058 #endif /* !MODULE */
6059
6060 static __exit void md_exit(void)
6061 {
6062         mddev_t *mddev;
6063         struct list_head *tmp;
6064
6065         blk_unregister_region(MKDEV(MAJOR_NR,0), 1U << MINORBITS);
6066         blk_unregister_region(MKDEV(mdp_major,0), 1U << MINORBITS);
6067
6068         unregister_blkdev(MAJOR_NR,"md");
6069         unregister_blkdev(mdp_major, "mdp");
6070         unregister_reboot_notifier(&md_notifier);
6071         unregister_sysctl_table(raid_table_header);
6072         remove_proc_entry("mdstat", NULL);
6073         for_each_mddev(mddev, tmp) {
6074                 struct gendisk *disk = mddev->gendisk;
6075                 if (!disk)
6076                         continue;
6077                 export_array(mddev);
6078                 del_gendisk(disk);
6079                 put_disk(disk);
6080                 mddev->gendisk = NULL;
6081                 mddev_put(mddev);
6082         }
6083 }
6084
6085 subsys_initcall(md_init);
6086 module_exit(md_exit)
6087
6088 static int get_ro(char *buffer, struct kernel_param *kp)
6089 {
6090         return sprintf(buffer, "%d", start_readonly);
6091 }
6092 static int set_ro(const char *val, struct kernel_param *kp)
6093 {
6094         char *e;
6095         int num = simple_strtoul(val, &e, 10);
6096         if (*val && (*e == '\0' || *e == '\n')) {
6097                 start_readonly = num;
6098                 return 0;
6099         }
6100         return -EINVAL;
6101 }
6102
6103 module_param_call(start_ro, set_ro, get_ro, NULL, S_IRUSR|S_IWUSR);
6104 module_param(start_dirty_degraded, int, S_IRUGO|S_IWUSR);
6105
6106
6107 EXPORT_SYMBOL(register_md_personality);
6108 EXPORT_SYMBOL(unregister_md_personality);
6109 EXPORT_SYMBOL(md_error);
6110 EXPORT_SYMBOL(md_done_sync);
6111 EXPORT_SYMBOL(md_write_start);
6112 EXPORT_SYMBOL(md_write_end);
6113 EXPORT_SYMBOL(md_register_thread);
6114 EXPORT_SYMBOL(md_unregister_thread);
6115 EXPORT_SYMBOL(md_wakeup_thread);
6116 EXPORT_SYMBOL(md_check_recovery);
6117 MODULE_LICENSE("GPL");
6118 MODULE_ALIAS("md");
6119 MODULE_ALIAS_BLOCKDEV_MAJOR(MD_MAJOR);