1 files changed, 3766 insertions, 0 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
new file mode 100644
index 000000000000..04562add1920
--- /dev/null
+++ b/drivers/md/md.c
@@ -0,0 +1,3766 @@
+/*
+   md.c : Multiple Devices driver for Linux
+          Copyright (C) 1998, 1999, 2000 Ingo Molnar
+
+     completely rewritten, based on the MD driver code from Marc Zyngier
+
+   Changes:
+
+   - RAID-1/RAID-5 extensions by Miguel de Icaza, Gadi Oxman, Ingo Molnar
+   - RAID-6 extensions by H. Peter Anvin <hpa@zytor.com>
+   - boot support for linear and striped mode by Harald Hoyer <HarryH@Royal.Net>
+   - kerneld support by Boris Tobotras <boris@xtalk.msk.su>
+   - kmod support by: Cyrus Durgin
+   - RAID0 bugfixes: Mark Anthony Lisher <markal@iname.com>
+   - Devfs support by Richard Gooch <rgooch@atnf.csiro.au>
+
+   - lots of fixes and improvements to the RAID1/RAID5 and generic
+     RAID code (such as request based resynchronization):
+
+     Neil Brown <neilb@cse.unsw.edu.au>.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   You should have received a copy of the GNU General Public License
+   (for example /usr/src/linux/COPYING); if not, write to the Free
+   Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include <linux/module.h>
+#include <linux/config.h>
+#include <linux/linkage.h>
+#include <linux/raid/md.h>
+#include <linux/sysctl.h>
+#include <linux/devfs_fs_kernel.h>
+#include <linux/buffer_head.h> /* for invalidate_bdev */
+#include <linux/suspend.h>
+
+#include <linux/init.h>
+
+#ifdef CONFIG_KMOD
+#include <linux/kmod.h>
+#endif
+
+#include <asm/unaligned.h>
+
+#define MAJOR_NR MD_MAJOR
+#define MD_DRIVER
+
+/* 63 partitions with the alternate major number (mdp) */
+#define MdpMinorShift 6
+
+#define DEBUG 0
+#define dprintk(x...) ((void)(DEBUG && printk(x)))
+
+
+#ifndef MODULE
+static void autostart_arrays (int part);
+#endif
+
+static mdk_personality_t *pers[MAX_PERSONALITY];
+static DEFINE_SPINLOCK(pers_lock);
+
+/*
+ * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
+ * is 1000 KB/sec, so the extra system load does not show up that much.
+ * Increase it if you want to have more _guaranteed_ speed. Note that
+ * the RAID driver will use the maximum available bandwith if the IO
+ * subsystem is idle. There is also an 'absolute maximum' reconstruction
+ * speed limit - in case reconstruction slows down your system despite
+ * idle IO detection.
+ *
+ * you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
+ */
+
+static int sysctl_speed_limit_min = 1000;
+static int sysctl_speed_limit_max = 200000;
+
+static struct ctl_table_header *raid_table_header;
+
+static ctl_table raid_table[] = {
+        {
+                .ctl_name       = DEV_RAID_SPEED_LIMIT_MIN,
+                .procname       = "speed_limit_min",
+                .data           = &sysctl_speed_limit_min,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec,
+        },
+        {
+                .ctl_name       = DEV_RAID_SPEED_LIMIT_MAX,
+                .procname       = "speed_limit_max",
+                .data           = &sysctl_speed_limit_max,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec,
+        },
+        { .ctl_name = 0 }
+};
+
+static ctl_table raid_dir_table[] = {
+        {
+                .ctl_name       = DEV_RAID,
+                .procname       = "raid",
+                .maxlen         = 0,
+                .mode           = 0555,
+                .child          = raid_table,
+        },
+        { .ctl_name = 0 }
+};
+
+static ctl_table raid_root_table[] = {
+        {
+                .ctl_name       = CTL_DEV,
+                .procname       = "dev",
+                .maxlen         = 0,
+                .mode           = 0555,
+                .child          = raid_dir_table,
+        },
+        { .ctl_name = 0 }
+};
+
+static struct block_device_operations md_fops;
+
+/*
+ * Enables to iterate over all existing md arrays
+ * all_mddevs_lock protects this list.
+ */
+static LIST_HEAD(all_mddevs);
+static DEFINE_SPINLOCK(all_mddevs_lock);
+
+
+/*
+ * iterates through all used mddevs in the system.
+ * We take care to grab the all_mddevs_lock whenever navigating
+ * the list, and to always hold a refcount when unlocked.
+ * Any code which breaks out of this loop while own
+ * a reference to the current mddev and must mddev_put it.
+ */
+#define ITERATE_MDDEV(mddev,tmp)                                        \
+                                                                        \
+        for (({ spin_lock(&all_mddevs_lock);                            \
+                tmp = all_mddevs.next;                                  \
+                mddev = NULL;});                                        \
+             ({ if (tmp != &all_mddevs)                                 \
+                        mddev_get(list_entry(tmp, mddev_t, all_mddevs));\
+                spin_unlock(&all_mddevs_lock);                          \
+                if (mddev) mddev_put(mddev);                            \
+                mddev = list_entry(tmp, mddev_t, all_mddevs);           \
+                tmp != &all_mddevs;});                                  \
+             ({ spin_lock(&all_mddevs_lock);                            \
+                tmp = tmp->next;})                                      \
+                )
+
+
+static int md_fail_request (request_queue_t *q, struct bio *bio)
+{
+        bio_io_error(bio, bio->bi_size);
+        return 0;
+}
+
+static inline mddev_t *mddev_get(mddev_t *mddev)
+{
+        atomic_inc(&mddev->active);
+        return mddev;
+}
+
+static void mddev_put(mddev_t *mddev)
+{
+        if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
+                return;
+        if (!mddev->raid_disks && list_empty(&mddev->disks)) {
+                list_del(&mddev->all_mddevs);
+                blk_put_queue(mddev->queue);
+                kfree(mddev);
+        }
+        spin_unlock(&all_mddevs_lock);
+}
+
+static mddev_t * mddev_find(dev_t unit)
+{
+        mddev_t *mddev, *new = NULL;
+
+ retry:
+        spin_lock(&all_mddevs_lock);
+        list_for_each_entry(mddev, &all_mddevs, all_mddevs)
+                if (mddev->unit == unit) {
+                        mddev_get(mddev);
+                        spin_unlock(&all_mddevs_lock);
+                        if (new)
+                                kfree(new);
+                        return mddev;
+                }
+
+        if (new) {
+                list_add(&new->all_mddevs, &all_mddevs);
+                spin_unlock(&all_mddevs_lock);
+                return new;
+        }
+        spin_unlock(&all_mddevs_lock);
+
+        new = (mddev_t *) kmalloc(sizeof(*new), GFP_KERNEL);
+        if (!new)
+                return NULL;
+
+        memset(new, 0, sizeof(*new));
+
+        new->unit = unit;
+        if (MAJOR(unit) == MD_MAJOR)
+                new->md_minor = MINOR(unit);
+        else
+                new->md_minor = MINOR(unit) >> MdpMinorShift;
+
+        init_MUTEX(&new->reconfig_sem);
+        INIT_LIST_HEAD(&new->disks);
+        INIT_LIST_HEAD(&new->all_mddevs);
+        init_timer(&new->safemode_timer);
+        atomic_set(&new->active, 1);
+
+        new->queue = blk_alloc_queue(GFP_KERNEL);
+        if (!new->queue) {
+                kfree(new);
+                return NULL;
+        }
+
+        blk_queue_make_request(new->queue, md_fail_request);
+
+        goto retry;
+}
+
+static inline int mddev_lock(mddev_t * mddev)
+{
+        return down_interruptible(&mddev->reconfig_sem);
+}
+
+static inline void mddev_lock_uninterruptible(mddev_t * mddev)
+{
+        down(&mddev->reconfig_sem);
+}
+
+static inline int mddev_trylock(mddev_t * mddev)
+{
+        return down_trylock(&mddev->reconfig_sem);
+}
+
+static inline void mddev_unlock(mddev_t * mddev)
+{
+        up(&mddev->reconfig_sem);
+
+        if (mddev->thread)
+                md_wakeup_thread(mddev->thread);
+}
+
+mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr)
+{
+        mdk_rdev_t * rdev;
+        struct list_head *tmp;
+
+        ITERATE_RDEV(mddev,rdev,tmp) {
+                if (rdev->desc_nr == nr)
+                        return rdev;
+        }
+        return NULL;
+}
+
+static mdk_rdev_t * find_rdev(mddev_t * mddev, dev_t dev)
+{
+        struct list_head *tmp;
+        mdk_rdev_t *rdev;
+
+        ITERATE_RDEV(mddev,rdev,tmp) {
+                if (rdev->bdev->bd_dev == dev)
+                        return rdev;
+        }
+        return NULL;
+}
+
+inline static sector_t calc_dev_sboffset(struct block_device *bdev)
+{
+        sector_t size = bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
+        return MD_NEW_SIZE_BLOCKS(size);
+}
+
+static sector_t calc_dev_size(mdk_rdev_t *rdev, unsigned chunk_size)
+{
+        sector_t size;
+
+        size = rdev->sb_offset;
+
+        if (chunk_size)
+                size &= ~((sector_t)chunk_size/1024 - 1);
+        return size;
+}
+
+static int alloc_disk_sb(mdk_rdev_t * rdev)
+{
+        if (rdev->sb_page)
+                MD_BUG();
+
+        rdev->sb_page = alloc_page(GFP_KERNEL);
+        if (!rdev->sb_page) {
+                printk(KERN_ALERT "md: out of memory.\n");
+                return -EINVAL;
+        }
+
+        return 0;
+}
+
+static void free_disk_sb(mdk_rdev_t * rdev)
+{
+        if (rdev->sb_page) {
+                page_cache_release(rdev->sb_page);
+                rdev->sb_loaded = 0;
+                rdev->sb_page = NULL;
+                rdev->sb_offset = 0;
+                rdev->size = 0;
+        }
+}
+
+
+static int bi_complete(struct bio *bio, unsigned int bytes_done, int error)
+{
+        if (bio->bi_size)
+                return 1;
+
+        complete((struct completion*)bio->bi_private);
+        return 0;
+}
+
+static int sync_page_io(struct block_device *bdev, sector_t sector, int size,
+                   struct page *page, int rw)
+{
+        struct bio *bio = bio_alloc(GFP_KERNEL, 1);
+        struct completion event;
+        int ret;
+
+        rw |= (1 << BIO_RW_SYNC);
+
+        bio->bi_bdev = bdev;
+        bio->bi_sector = sector;
+        bio_add_page(bio, page, size, 0);
+        init_completion(&event);
+        bio->bi_private = &event;
+        bio->bi_end_io = bi_complete;
+        submit_bio(rw, bio);
+        wait_for_completion(&event);
+
+        ret = test_bit(BIO_UPTODATE, &bio->bi_flags);
+        bio_put(bio);
+        return ret;
+}
+
+static int read_disk_sb(mdk_rdev_t * rdev)
+{
+        char b[BDEVNAME_SIZE];
+        if (!rdev->sb_page) {
+                MD_BUG();
+                return -EINVAL;
+        }
+        if (rdev->sb_loaded)
+                return 0;
+
+
+        if (!sync_page_io(rdev->bdev, rdev->sb_offset<<1, MD_SB_BYTES, rdev->sb_page, READ))
+                goto fail;
+        rdev->sb_loaded = 1;
+        return 0;
+
+fail:
+        printk(KERN_WARNING "md: disabled device %s, could not read superblock.\n",
+                bdevname(rdev->bdev,b));
+        return -EINVAL;
+}
+
+static int uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
+{
+        if (    (sb1->set_uuid0 == sb2->set_uuid0) &&
+                (sb1->set_uuid1 == sb2->set_uuid1) &&
+                (sb1->set_uuid2 == sb2->set_uuid2) &&
+                (sb1->set_uuid3 == sb2->set_uuid3))
+
+                return 1;
+
+        return 0;
+}
+
+
+static int sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
+{
+        int ret;
+        mdp_super_t *tmp1, *tmp2;
+
+        tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
+        tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
+
+        if (!tmp1 || !tmp2) {
+                ret = 0;
+                printk(KERN_INFO "md.c: sb1 is not equal to sb2!\n");
+                goto abort;
+        }
+
+        *tmp1 = *sb1;
+        *tmp2 = *sb2;
+
+        /*
+         * nr_disks is not constant
+         */
+        tmp1->nr_disks = 0;
+        tmp2->nr_disks = 0;
+
+        if (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4))
+                ret = 0;
+        else
+                ret = 1;
+
+abort:
+        if (tmp1)
+                kfree(tmp1);
+        if (tmp2)
+                kfree(tmp2);
+
+        return ret;
+}
+
+static unsigned int calc_sb_csum(mdp_super_t * sb)
+{
+        unsigned int disk_csum, csum;
+
+        disk_csum = sb->sb_csum;
+        sb->sb_csum = 0;
+        csum = csum_partial((void *)sb, MD_SB_BYTES, 0);
+        sb->sb_csum = disk_csum;
+        return csum;
+}
+
+
+/*
+ * Handle superblock details.
+ * We want to be able to handle multiple superblock formats
+ * so we have a common interface to them all, and an array of
+ * different handlers.
+ * We rely on user-space to write the initial superblock, and support
+ * reading and updating of superblocks.
+ * Interface methods are:
+ *   int load_super(mdk_rdev_t *dev, mdk_rdev_t *refdev, int minor_version)
+ *      loads and validates a superblock on dev.
+ *      if refdev != NULL, compare superblocks on both devices
+ *    Return:
+ *      0 - dev has a superblock that is compatible with refdev
+ *      1 - dev has a superblock that is compatible and newer than refdev
+ *          so dev should be used as the refdev in future
+ *     -EINVAL superblock incompatible or invalid
+ *     -othererror e.g. -EIO
+ *
+ *   int validate_super(mddev_t *mddev, mdk_rdev_t *dev)
+ *      Verify that dev is acceptable into mddev.
+ *       The first time, mddev->raid_disks will be 0, and data from
+ *       dev should be merged in.  Subsequent calls check that dev
+ *       is new enough.  Return 0 or -EINVAL
+ *
+ *   void sync_super(mddev_t *mddev, mdk_rdev_t *dev)
+ *     Update the superblock for rdev with data in mddev
+ *     This does not write to disc.
+ *
+ */
+
+struct super_type  {
+        char            *name;
+        struct module   *owner;
+        int             (*load_super)(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version);
+        int             (*validate_super)(mddev_t *mddev, mdk_rdev_t *rdev);
+        void            (*sync_super)(mddev_t *mddev, mdk_rdev_t *rdev);
+};
+
+/*
+ * load_super for 0.90.0 
+ */
+static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
+{
+        char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
+        mdp_super_t *sb;
+        int ret;
+        sector_t sb_offset;
+
+        /*
+         * Calculate the position of the superblock,
+         * it's at the end of the disk.
+         *
+         * It also happens to be a multiple of 4Kb.
+         */
+        sb_offset = calc_dev_sboffset(rdev->bdev);
+        rdev->sb_offset = sb_offset;
+
+        ret = read_disk_sb(rdev);
+        if (ret) return ret;
+
+        ret = -EINVAL;
+
+        bdevname(rdev->bdev, b);
+        sb = (mdp_super_t*)page_address(rdev->sb_page);
+
+        if (sb->md_magic != MD_SB_MAGIC) {
+                printk(KERN_ERR "md: invalid raid superblock magic on %s\n",
+                       b);
+                goto abort;
+        }
+
+        if (sb->major_version != 0 ||
+            sb->minor_version != 90) {
+                printk(KERN_WARNING "Bad version number %d.%d on %s\n",
+                        sb->major_version, sb->minor_version,
+                        b);
+                goto abort;
+        }
+
+        if (sb->raid_disks <= 0)
+                goto abort;
+
+        if (csum_fold(calc_sb_csum(sb)) != csum_fold(sb->sb_csum)) {
+                printk(KERN_WARNING "md: invalid superblock checksum on %s\n",
+                        b);
+                goto abort;
+        }
+
+        rdev->preferred_minor = sb->md_minor;
+        rdev->data_offset = 0;
+
+        if (sb->level == LEVEL_MULTIPATH)
+                rdev->desc_nr = -1;
+        else
+                rdev->desc_nr = sb->this_disk.number;
+
+        if (refdev == 0)
+                ret = 1;
+        else {
+                __u64 ev1, ev2;
+                mdp_super_t *refsb = (mdp_super_t*)page_address(refdev->sb_page);
+                if (!uuid_equal(refsb, sb)) {
+                        printk(KERN_WARNING "md: %s has different UUID to %s\n",
+                                b, bdevname(refdev->bdev,b2));
+                        goto abort;
+                }
+                if (!sb_equal(refsb, sb)) {
+                        printk(KERN_WARNING "md: %s has same UUID"
+                               " but different superblock to %s\n",
+                               b, bdevname(refdev->bdev, b2));
+                        goto abort;
+                }
+                ev1 = md_event(sb);
+                ev2 = md_event(refsb);
+                if (ev1 > ev2)
+                        ret = 1;
+                else 
+                        ret = 0;
+        }
+        rdev->size = calc_dev_size(rdev, sb->chunk_size);
+
+ abort:
+        return ret;
+}
+
+/*
+ * validate_super for 0.90.0
+ */
+static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
+{
+        mdp_disk_t *desc;
+        mdp_super_t *sb = (mdp_super_t *)page_address(rdev->sb_page);
+
+        if (mddev->raid_disks == 0) {
+                mddev->major_version = 0;
+                mddev->minor_version = sb->minor_version;
+                mddev->patch_version = sb->patch_version;
+                mddev->persistent = ! sb->not_persistent;
+                mddev->chunk_size = sb->chunk_size;
+                mddev->ctime = sb->ctime;
+                mddev->utime = sb->utime;
+                mddev->level = sb->level;
+                mddev->layout = sb->layout;
+                mddev->raid_disks = sb->raid_disks;
+                mddev->size = sb->size;
+                mddev->events = md_event(sb);
+
+                if (sb->state & (1<<MD_SB_CLEAN))
+                        mddev->recovery_cp = MaxSector;
+                else {
+                        if (sb->events_hi == sb->cp_events_hi && 
+                                sb->events_lo == sb->cp_events_lo) {
+                                mddev->recovery_cp = sb->recovery_cp;
+                        } else
+                                mddev->recovery_cp = 0;
+                }
+
+                memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
+                memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
+                memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
+                memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
+
+                mddev->max_disks = MD_SB_DISKS;
+        } else {
+                __u64 ev1;
+                ev1 = md_event(sb);
+                ++ev1;
+                if (ev1 < mddev->events) 
+                        return -EINVAL;
+        }
+        if (mddev->level != LEVEL_MULTIPATH) {
+                rdev->raid_disk = -1;
+                rdev->in_sync = rdev->faulty = 0;
+                desc = sb->disks + rdev->desc_nr;
+
+                if (desc->state & (1<<MD_DISK_FAULTY))
+                        rdev->faulty = 1;
+                else if (desc->state & (1<<MD_DISK_SYNC) &&
+                         desc->raid_disk < mddev->raid_disks) {
+                        rdev->in_sync = 1;
+                        rdev->raid_disk = desc->raid_disk;
+                }
+        }
+        return 0;
+}
+
+/*
+ * sync_super for 0.90.0
+ */
+static void super_90_sync(mddev_t *mddev, mdk_rdev_t *rdev)
+{
+        mdp_super_t *sb;
+        struct list_head *tmp;
+        mdk_rdev_t *rdev2;
+        int next_spare = mddev->raid_disks;
+
+        /* make rdev->sb match mddev data..
+         *
+         * 1/ zero out disks
+         * 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
+         * 3/ any empty disks < next_spare become removed
+         *
+         * disks[0] gets initialised to REMOVED because
+         * we cannot be sure from other fields if it has
+         * been initialised or not.
+         */
+        int i;
+        int active=0, working=0,failed=0,spare=0,nr_disks=0;
+
+        sb = (mdp_super_t*)page_address(rdev->sb_page);
+
+        memset(sb, 0, sizeof(*sb));
+
+        sb->md_magic = MD_SB_MAGIC;
+        sb->major_version = mddev->major_version;
+        sb->minor_version = mddev->minor_version;
+        sb->patch_version = mddev->patch_version;
+        sb->gvalid_words  = 0; /* ignored */
+        memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
+        memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
+        memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
+        memcpy(&sb->set_uuid3, mddev->uuid+12,4);
+
+        sb->ctime = mddev->ctime;
+        sb->level = mddev->level;
+        sb->size  = mddev->size;
+        sb->raid_disks = mddev->raid_disks;
+        sb->md_minor = mddev->md_minor;
+        sb->not_persistent = !mddev->persistent;
+        sb->utime = mddev->utime;
+        sb->state = 0;
+        sb->events_hi = (mddev->events>>32);
+        sb->events_lo = (u32)mddev->events;
+
+        if (mddev->in_sync)
+        {
+                sb->recovery_cp = mddev->recovery_cp;
+                sb->cp_events_hi = (mddev->events>>32);
+                sb->cp_events_lo = (u32)mddev->events;
+                if (mddev->recovery_cp == MaxSector)
+                        sb->state = (1<< MD_SB_CLEAN);
+        } else
+                sb->recovery_cp = 0;
+
+        sb->layout = mddev->layout;
+        sb->chunk_size = mddev->chunk_size;
+
+        sb->disks[0].state = (1<<MD_DISK_REMOVED);
+        ITERATE_RDEV(mddev,rdev2,tmp) {
+                mdp_disk_t *d;
+                if (rdev2->raid_disk >= 0 && rdev2->in_sync && !rdev2->faulty)
+                        rdev2->desc_nr = rdev2->raid_disk;
+                else
+                        rdev2->desc_nr = next_spare++;
+                d = &sb->disks[rdev2->desc_nr];
+                nr_disks++;
+                d->number = rdev2->desc_nr;
+                d->major = MAJOR(rdev2->bdev->bd_dev);
+                d->minor = MINOR(rdev2->bdev->bd_dev);
+                if (rdev2->raid_disk >= 0 && rdev->in_sync && !rdev2->faulty)
+                        d->raid_disk = rdev2->raid_disk;
+                else
+                        d->raid_disk = rdev2->desc_nr; /* compatibility */
+                if (rdev2->faulty) {
+                        d->state = (1<<MD_DISK_FAULTY);
+                        failed++;
+                } else if (rdev2->in_sync) {
+                        d->state = (1<<MD_DISK_ACTIVE);
+                        d->state |= (1<<MD_DISK_SYNC);
+                        active++;
+                        working++;
+                } else {
+                        d->state = 0;
+                        spare++;
+                        working++;
+                }
+        }
+        
+        /* now set the "removed" and "faulty" bits on any missing devices */
+        for (i=0 ; i < mddev->raid_disks ; i++) {
+                mdp_disk_t *d = &sb->disks[i];
+                if (d->state == 0 && d->number == 0) {
+                        d->number = i;
+                        d->raid_disk = i;
+                        d->state = (1<<MD_DISK_REMOVED);
+                        d->state |= (1<<MD_DISK_FAULTY);
+                        failed++;
+                }
+        }
+        sb->nr_disks = nr_disks;
+        sb->active_disks = active;
+        sb->working_disks = working;
+        sb->failed_disks = failed;
+        sb->spare_disks = spare;
+
+        sb->this_disk = sb->disks[rdev->desc_nr];
+        sb->sb_csum = calc_sb_csum(sb);
+}
+
+/*
+ * version 1 superblock
+ */
+
+static unsigned int calc_sb_1_csum(struct mdp_superblock_1 * sb)
+{
+        unsigned int disk_csum, csum;
+        unsigned long long newcsum;
+        int size = 256 + le32_to_cpu(sb->max_dev)*2;
+        unsigned int *isuper = (unsigned int*)sb;
+        int i;
+
+        disk_csum = sb->sb_csum;
+        sb->sb_csum = 0;
+        newcsum = 0;
+        for (i=0; size>=4; size -= 4 )
+                newcsum += le32_to_cpu(*isuper++);
+
+        if (size == 2)
+                newcsum += le16_to_cpu(*(unsigned short*) isuper);
+
+        csum = (newcsum & 0xffffffff) + (newcsum >> 32);
+        sb->sb_csum = disk_csum;
+        return cpu_to_le32(csum);
+}
+
+static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
+{
+        struct mdp_superblock_1 *sb;
+        int ret;
+        sector_t sb_offset;
+        char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
+
+        /*
+         * Calculate the position of the superblock.
+         * It is always aligned to a 4K boundary and
+         * depeding on minor_version, it can be:
+         * 0: At least 8K, but less than 12K, from end of device
+         * 1: At start of device
+         * 2: 4K from start of device.
+         */
+        switch(minor_version) {
+        case 0:
+                sb_offset = rdev->bdev->bd_inode->i_size >> 9;
+                sb_offset -= 8*2;
+                sb_offset &= ~(4*2-1);
+                /* convert from sectors to K */
+                sb_offset /= 2;
+                break;
+        case 1:
+                sb_offset = 0;
+                break;
+        case 2:
+                sb_offset = 4;
+                break;
+        default:
+                return -EINVAL;
+        }
+        rdev->sb_offset = sb_offset;
+
+        ret = read_disk_sb(rdev);
+        if (ret) return ret;
+
+
+        sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
+
+        if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
+            sb->major_version != cpu_to_le32(1) ||
+            le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
+            le64_to_cpu(sb->super_offset) != (rdev->sb_offset<<1) ||
+            sb->feature_map != 0)
+                return -EINVAL;
+
+        if (calc_sb_1_csum(sb) != sb->sb_csum) {
+                printk("md: invalid superblock checksum on %s\n",
+                        bdevname(rdev->bdev,b));
+                return -EINVAL;
+        }
+        if (le64_to_cpu(sb->data_size) < 10) {
+                printk("md: data_size too small on %s\n",
+                       bdevname(rdev->bdev,b));
+                return -EINVAL;
+        }
+        rdev->preferred_minor = 0xffff;
+        rdev->data_offset = le64_to_cpu(sb->data_offset);
+
+        if (refdev == 0)
+                return 1;
+        else {
+                __u64 ev1, ev2;
+                struct mdp_superblock_1 *refsb = 
+                        (struct mdp_superblock_1*)page_address(refdev->sb_page);
+
+                if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
+                    sb->level != refsb->level ||
+                    sb->layout != refsb->layout ||
+                    sb->chunksize != refsb->chunksize) {
+                        printk(KERN_WARNING "md: %s has strangely different"
+                                " superblock to %s\n",
+                                bdevname(rdev->bdev,b),
+                                bdevname(refdev->bdev,b2));
+                        return -EINVAL;
+                }
+                ev1 = le64_to_cpu(sb->events);
+                ev2 = le64_to_cpu(refsb->events);
+
+                if (ev1 > ev2)
+                        return 1;
+        }
+        if (minor_version) 
+                rdev->size = ((rdev->bdev->bd_inode->i_size>>9) - le64_to_cpu(sb->data_offset)) / 2;
+        else
+                rdev->size = rdev->sb_offset;
+        if (rdev->size < le64_to_cpu(sb->data_size)/2)
+                return -EINVAL;
+        rdev->size = le64_to_cpu(sb->data_size)/2;
+        if (le32_to_cpu(sb->chunksize))
+                rdev->size &= ~((sector_t)le32_to_cpu(sb->chunksize)/2 - 1);
+        return 0;
+}
+
+static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
+{
+        struct mdp_superblock_1 *sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
+
+        if (mddev->raid_disks == 0) {
+                mddev->major_version = 1;
+                mddev->patch_version = 0;
+                mddev->persistent = 1;
+                mddev->chunk_size = le32_to_cpu(sb->chunksize) << 9;
+                mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);
+                mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);
+                mddev->level = le32_to_cpu(sb->level);
+                mddev->layout = le32_to_cpu(sb->layout);
+                mddev->raid_disks = le32_to_cpu(sb->raid_disks);
+                mddev->size = le64_to_cpu(sb->size)/2;
+                mddev->events = le64_to_cpu(sb->events);
+                
+                mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
+                memcpy(mddev->uuid, sb->set_uuid, 16);
+
+                mddev->max_disks =  (4096-256)/2;
+        } else {
+                __u64 ev1;
+                ev1 = le64_to_cpu(sb->events);
+                ++ev1;
+                if (ev1 < mddev->events)
+                        return -EINVAL;
+        }
+
+        if (mddev->level != LEVEL_MULTIPATH) {
+                int role;
+                rdev->desc_nr = le32_to_cpu(sb->dev_number);
+                role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
+                switch(role) {
+                case 0xffff: /* spare */
+                        rdev->in_sync = 0;
+                        rdev->faulty = 0;
+                        rdev->raid_disk = -1;
+                        break;
+                case 0xfffe: /* faulty */
+                        rdev->in_sync = 0;
+                        rdev->faulty = 1;
+                        rdev->raid_disk = -1;
+                        break;
+                default:
+                        rdev->in_sync = 1;
+                        rdev->faulty = 0;
+                        rdev->raid_disk = role;
+                        break;
+                }
+        }
+        return 0;
+}
+
+static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
+{
+        struct mdp_superblock_1 *sb;
+        struct list_head *tmp;
+        mdk_rdev_t *rdev2;
+        int max_dev, i;
+        /* make rdev->sb match mddev and rdev data. */
+
+        sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
+
+        sb->feature_map = 0;
+        sb->pad0 = 0;
+        memset(sb->pad1, 0, sizeof(sb->pad1));
+        memset(sb->pad2, 0, sizeof(sb->pad2));
+        memset(sb->pad3, 0, sizeof(sb->pad3));
+
+        sb->utime = cpu_to_le64((__u64)mddev->utime);
+        sb->events = cpu_to_le64(mddev->events);
+        if (mddev->in_sync)
+                sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
+        else
+                sb->resync_offset = cpu_to_le64(0);
+
+        max_dev = 0;
+        ITERATE_RDEV(mddev,rdev2,tmp)
+                if (rdev2->desc_nr+1 > max_dev)
+                        max_dev = rdev2->desc_nr+1;
+        
+        sb->max_dev = cpu_to_le32(max_dev);
+        for (i=0; i<max_dev;i++)
+                sb->dev_roles[i] = cpu_to_le16(0xfffe);
+        
+        ITERATE_RDEV(mddev,rdev2,tmp) {
+                i = rdev2->desc_nr;
+                if (rdev2->faulty)
+                        sb->dev_roles[i] = cpu_to_le16(0xfffe);
+                else if (rdev2->in_sync)
+                        sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
+                else
+                        sb->dev_roles[i] = cpu_to_le16(0xffff);
+        }
+
+        sb->recovery_offset = cpu_to_le64(0); /* not supported yet */
+        sb->sb_csum = calc_sb_1_csum(sb);
+}
+
+
+struct super_type super_types[] = {
+        [0] = {
+                .name   = "0.90.0",
+                .owner  = THIS_MODULE,
+                .load_super     = super_90_load,
+                .validate_super = super_90_validate,
+                .sync_super     = super_90_sync,
+        },
+        [1] = {
+                .name   = "md-1",
+                .owner  = THIS_MODULE,
+                .load_super     = super_1_load,
+                .validate_super = super_1_validate,
+                .sync_super     = super_1_sync,
+        },
+};
+        
+static mdk_rdev_t * match_dev_unit(mddev_t *mddev, mdk_rdev_t *dev)
+{
+        struct list_head *tmp;
+        mdk_rdev_t *rdev;
+
+        ITERATE_RDEV(mddev,rdev,tmp)
+                if (rdev->bdev->bd_contains == dev->bdev->bd_contains)
+                        return rdev;
+
+        return NULL;
+}
+
+static int match_mddev_units(mddev_t *mddev1, mddev_t *mddev2)
+{
+        struct list_head *tmp;
+        mdk_rdev_t *rdev;
+
+        ITERATE_RDEV(mddev1,rdev,tmp)
+                if (match_dev_unit(mddev2, rdev))
+                        return 1;
+
+        return 0;
+}
+
+static LIST_HEAD(pending_raid_disks);
+
+static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
+{
+        mdk_rdev_t *same_pdev;
+        char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
+
+        if (rdev->mddev) {
+                MD_BUG();
+                return -EINVAL;
+        }
+        same_pdev = match_dev_unit(mddev, rdev);
+        if (same_pdev)
+                printk(KERN_WARNING
+                        "%s: WARNING: %s appears to be on the same physical"
+                        " disk as %s. True\n     protection against single-disk"
+                        " failure might be compromised.\n",
+                        mdname(mddev), bdevname(rdev->bdev,b),
+                        bdevname(same_pdev->bdev,b2));
+
+        /* Verify rdev->desc_nr is unique.
+         * If it is -1, assign a free number, else
+         * check number is not in use
+         */
+        if (rdev->desc_nr < 0) {
+                int choice = 0;
+                if (mddev->pers) choice = mddev->raid_disks;
+                while (find_rdev_nr(mddev, choice))
+                        choice++;
+                rdev->desc_nr = choice;
+        } else {
+                if (find_rdev_nr(mddev, rdev->desc_nr))
+                        return -EBUSY;
+        }
+                        
+        list_add(&rdev->same_set, &mddev->disks);
+        rdev->mddev = mddev;
+        printk(KERN_INFO "md: bind<%s>\n", bdevname(rdev->bdev,b));
+        return 0;
+}
+
+static void unbind_rdev_from_array(mdk_rdev_t * rdev)
+{
+        char b[BDEVNAME_SIZE];
+        if (!rdev->mddev) {
+                MD_BUG();
+                return;
+        }
+        list_del_init(&rdev->same_set);
+        printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
+        rdev->mddev = NULL;
+}
+
+/*
+ * prevent the device from being mounted, repartitioned or
+ * otherwise reused by a RAID array (or any other kernel
+ * subsystem), by bd_claiming the device.
+ */
+static int lock_rdev(mdk_rdev_t *rdev, dev_t dev)
+{
+        int err = 0;
+        struct block_device *bdev;
+        char b[BDEVNAME_SIZE];
+
+        bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
+        if (IS_ERR(bdev)) {
+                printk(KERN_ERR "md: could not open %s.\n",
+                        __bdevname(dev, b));
+                return PTR_ERR(bdev);
+        }
+        err = bd_claim(bdev, rdev);
+        if (err) {
+                printk(KERN_ERR "md: could not bd_claim %s.\n",
+                        bdevname(bdev, b));
+                blkdev_put(bdev);
+                return err;
+        }
+        rdev->bdev = bdev;
+        return err;
+}
+
+static void unlock_rdev(mdk_rdev_t *rdev)
+{
+        struct block_device *bdev = rdev->bdev;
+        rdev->bdev = NULL;
+        if (!bdev)
+                MD_BUG();
+        bd_release(bdev);
+        blkdev_put(bdev);
+}
+
+void md_autodetect_dev(dev_t dev);
+
+static void export_rdev(mdk_rdev_t * rdev)
+{
+        char b[BDEVNAME_SIZE];
+        printk(KERN_INFO "md: export_rdev(%s)\n",
+                bdevname(rdev->bdev,b));
+        if (rdev->mddev)
+                MD_BUG();
+        free_disk_sb(rdev);
+        list_del_init(&rdev->same_set);
+#ifndef MODULE
+        md_autodetect_dev(rdev->bdev->bd_dev);
+#endif
+        unlock_rdev(rdev);
+        kfree(rdev);
+}
+
+static void kick_rdev_from_array(mdk_rdev_t * rdev)
+{
+        unbind_rdev_from_array(rdev);
+        export_rdev(rdev);
+}
+
+static void export_array(mddev_t *mddev)
+{
+        struct list_head *tmp;
+        mdk_rdev_t *rdev;
+
+        ITERATE_RDEV(mddev,rdev,tmp) {
+                if (!rdev->mddev) {
+                        MD_BUG();
+                        continue;
+                }
+                kick_rdev_from_array(rdev);
+        }
+        if (!list_empty(&mddev->disks))
+                MD_BUG();
+        mddev->raid_disks = 0;
+        mddev->major_version = 0;
+}
+
+static void print_desc(mdp_disk_t *desc)
+{
+        printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
+                desc->major,desc->minor,desc->raid_disk,desc->state);
+}
+
+static void print_sb(mdp_super_t *sb)
+{
+        int i;
+
+        printk(KERN_INFO 
+                "md:  SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
+                sb->major_version, sb->minor_version, sb->patch_version,
+                sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
+                sb->ctime);
+        printk(KERN_INFO "md:     L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
+                sb->level, sb->size, sb->nr_disks, sb->raid_disks,
+                sb->md_minor, sb->layout, sb->chunk_size);
+        printk(KERN_INFO "md:     UT:%08x ST:%d AD:%d WD:%d"
+                " FD:%d SD:%d CSUM:%08x E:%08lx\n",
+                sb->utime, sb->state, sb->active_disks, sb->working_disks,
+                sb->failed_disks, sb->spare_disks,
+                sb->sb_csum, (unsigned long)sb->events_lo);
+
+        printk(KERN_INFO);
+        for (i = 0; i < MD_SB_DISKS; i++) {
+                mdp_disk_t *desc;
+
+                desc = sb->disks + i;
+                if (desc->number || desc->major || desc->minor ||
+                    desc->raid_disk || (desc->state && (desc->state != 4))) {
+                        printk("     D %2d: ", i);
+                        print_desc(desc);
+                }
+        }
+        printk(KERN_INFO "md:     THIS: ");
+        print_desc(&sb->this_disk);
+
+}
+
+static void print_rdev(mdk_rdev_t *rdev)
+{
+        char b[BDEVNAME_SIZE];
+        printk(KERN_INFO "md: rdev %s, SZ:%08llu F:%d S:%d DN:%u\n",
+                bdevname(rdev->bdev,b), (unsigned long long)rdev->size,
+                rdev->faulty, rdev->in_sync, rdev->desc_nr);
+        if (rdev->sb_loaded) {
+                printk(KERN_INFO "md: rdev superblock:\n");
+                print_sb((mdp_super_t*)page_address(rdev->sb_page));
+        } else
+                printk(KERN_INFO "md: no rdev superblock!\n");
+}
+
+void md_print_devices(void)
+{
+        struct list_head *tmp, *tmp2;
+        mdk_rdev_t *rdev;
+        mddev_t *mddev;
+        char b[BDEVNAME_SIZE];
+
+        printk("\n");
+        printk("md:     **********************************\n");
+        printk("md:     * <COMPLETE RAID STATE PRINTOUT> *\n");
+        printk("md:     **********************************\n");
+        ITERATE_MDDEV(mddev,tmp) {
+                printk("%s: ", mdname(mddev));
+
+                ITERATE_RDEV(mddev,rdev,tmp2)
+                        printk("<%s>", bdevname(rdev->bdev,b));
+                printk("\n");
+
+                ITERATE_RDEV(mddev,rdev,tmp2)
+                        print_rdev(rdev);
+        }
+        printk("md:     **********************************\n");
+        printk("\n");
+}
+
+
+static int write_disk_sb(mdk_rdev_t * rdev)
+{
+        char b[BDEVNAME_SIZE];
+        if (!rdev->sb_loaded) {
+                MD_BUG();
+                return 1;
+        }
+        if (rdev->faulty) {
+                MD_BUG();
+                return 1;
+        }
+
+        dprintk(KERN_INFO "(write) %s's sb offset: %llu\n",
+                bdevname(rdev->bdev,b),
+               (unsigned long long)rdev->sb_offset);
+  
+        if (sync_page_io(rdev->bdev, rdev->sb_offset<<1, MD_SB_BYTES, rdev->sb_page, WRITE))
+                return 0;
+
+        printk("md: write_disk_sb failed for device %s\n", 
+                bdevname(rdev->bdev,b));
+        return 1;
+}
+
+static void sync_sbs(mddev_t * mddev)
+{
+        mdk_rdev_t *rdev;
+        struct list_head *tmp;
+
+        ITERATE_RDEV(mddev,rdev,tmp) {
+                super_types[mddev->major_version].
+                        sync_super(mddev, rdev);
+                rdev->sb_loaded = 1;
+        }
+}
+
+static void md_update_sb(mddev_t * mddev)
+{
+        int err, count = 100;
+        struct list_head *tmp;
+        mdk_rdev_t *rdev;
+
+        mddev->sb_dirty = 0;
+repeat:
+        mddev->utime = get_seconds();
+        mddev->events ++;
+
+        if (!mddev->events) {
+                /*
+                 * oops, this 64-bit counter should never wrap.
+                 * Either we are in around ~1 trillion A.C., assuming
+                 * 1 reboot per second, or we have a bug:
+                 */
+                MD_BUG();
+                mddev->events --;
+        }
+        sync_sbs(mddev);
+
+        /*
+         * do not write anything to disk if using
+         * nonpersistent superblocks
+         */
+        if (!mddev->persistent)
+                return;
+
+        dprintk(KERN_INFO 
+                "md: updating %s RAID superblock on device (in sync %d)\n",
+                mdname(mddev),mddev->in_sync);
+
+        err = 0;
+        ITERATE_RDEV(mddev,rdev,tmp) {
+                char b[BDEVNAME_SIZE];
+                dprintk(KERN_INFO "md: ");
+                if (rdev->faulty)
+                        dprintk("(skipping faulty ");
+
+                dprintk("%s ", bdevname(rdev->bdev,b));
+                if (!rdev->faulty) {
+                        err += write_disk_sb(rdev);
+                } else
+                        dprintk(")\n");
+                if (!err && mddev->level == LEVEL_MULTIPATH)
+                        /* only need to write one superblock... */
+                        break;
+        }
+        if (err) {
+                if (--count) {
+                        printk(KERN_ERR "md: errors occurred during superblock"
+                                " update, repeating\n");
+                        goto repeat;
+                }
+                printk(KERN_ERR \
+                        "md: excessive errors occurred during superblock update, exiting\n");
+        }
+}
+
+/*
+ * Import a device. If 'super_format' >= 0, then sanity check the superblock
+ *
+ * mark the device faulty if:
+ *
+ *   - the device is nonexistent (zero size)
+ *   - the device has no valid superblock
+ *
+ * a faulty rdev _never_ has rdev->sb set.
+ */
+static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_minor)
+{
+        char b[BDEVNAME_SIZE];
+        int err;
+        mdk_rdev_t *rdev;
+        sector_t size;
+
+        rdev = (mdk_rdev_t *) kmalloc(sizeof(*rdev), GFP_KERNEL);
+        if (!rdev) {
+                printk(KERN_ERR "md: could not alloc mem for new device!\n");
+                return ERR_PTR(-ENOMEM);
+        }
+        memset(rdev, 0, sizeof(*rdev));
+
+        if ((err = alloc_disk_sb(rdev)))
+                goto abort_free;
+
+        err = lock_rdev(rdev, newdev);
+        if (err)
+                goto abort_free;
+
+        rdev->desc_nr = -1;
+        rdev->faulty = 0;
+        rdev->in_sync = 0;
+        rdev->data_offset = 0;
+        atomic_set(&rdev->nr_pending, 0);
+
+        size = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
+        if (!size) {
+                printk(KERN_WARNING 
+                        "md: %s has zero or unknown size, marking faulty!\n",
+                        bdevname(rdev->bdev,b));
+                err = -EINVAL;
+                goto abort_free;
+        }
+
+        if (super_format >= 0) {
+                err = super_types[super_format].
+                        load_super(rdev, NULL, super_minor);
+                if (err == -EINVAL) {
+                        printk(KERN_WARNING 
+                                "md: %s has invalid sb, not importing!\n",
+                                bdevname(rdev->bdev,b));
+                        goto abort_free;
+                }
+                if (err < 0) {
+                        printk(KERN_WARNING 
+                                "md: could not read %s's sb, not importing!\n",
+                                bdevname(rdev->bdev,b));
+                        goto abort_free;
+                }
+        }
+        INIT_LIST_HEAD(&rdev->same_set);
+
+        return rdev;
+
+abort_free:
+        if (rdev->sb_page) {
+                if (rdev->bdev)
+                        unlock_rdev(rdev);
+                free_disk_sb(rdev);
+        }
+        kfree(rdev);
+        return ERR_PTR(err);
+}
+
+/*
+ * Check a full RAID array for plausibility
+ */
+
+
+static int analyze_sbs(mddev_t * mddev)
+{
+        int i;
+        struct list_head *tmp;
+        mdk_rdev_t *rdev, *freshest;
+        char b[BDEVNAME_SIZE];
+
+        freshest = NULL;
+        ITERATE_RDEV(mddev,rdev,tmp)
+                switch (super_types[mddev->major_version].
+                        load_super(rdev, freshest, mddev->minor_version)) {
+                case 1:
+                        freshest = rdev;
+                        break;
+                case 0:
+                        break;
+                default:
+                        printk( KERN_ERR \
+                                "md: fatal superblock inconsistency in %s"
+                                " -- removing from array\n", 
+                                bdevname(rdev->bdev,b));
+                        kick_rdev_from_array(rdev);
+                }
+
+
+        super_types[mddev->major_version].
+                validate_super(mddev, freshest);
+
+        i = 0;
+        ITERATE_RDEV(mddev,rdev,tmp) {
+                if (rdev != freshest)
+                        if (super_types[mddev->major_version].
+                            validate_super(mddev, rdev)) {
+                                printk(KERN_WARNING "md: kicking non-fresh %s"
+                                        " from array!\n",
+                                        bdevname(rdev->bdev,b));
+                                kick_rdev_from_array(rdev);
+                                continue;
+                        }
+                if (mddev->level == LEVEL_MULTIPATH) {
+                        rdev->desc_nr = i++;
+                        rdev->raid_disk = rdev->desc_nr;
+                        rdev->in_sync = 1;
+                }
+        }
+
+
+
+        if (mddev->recovery_cp != MaxSector &&
+            mddev->level >= 1)
+                printk(KERN_ERR "md: %s: raid array is not clean"
+                       " -- starting background reconstruction\n",
+                       mdname(mddev));
+
+        return 0;
+}
+
+int mdp_major = 0;
+
+static struct kobject *md_probe(dev_t dev, int *part, void *data)
+{
+        static DECLARE_MUTEX(disks_sem);
+        mddev_t *mddev = mddev_find(dev);
+        struct gendisk *disk;
+        int partitioned = (MAJOR(dev) != MD_MAJOR);
+        int shift = partitioned ? MdpMinorShift : 0;
+        int unit = MINOR(dev) >> shift;
+
+        if (!mddev)
+                return NULL;
+
+        down(&disks_sem);
+        if (mddev->gendisk) {
+                up(&disks_sem);
+                mddev_put(mddev);
+                return NULL;
+        }
+        disk = alloc_disk(1 << shift);
+        if (!disk) {
+                up(&disks_sem);
+                mddev_put(mddev);
+                return NULL;
+        }
+        disk->major = MAJOR(dev);
+        disk->first_minor = unit << shift;
+        if (partitioned) {
+                sprintf(disk->disk_name, "md_d%d", unit);
+                sprintf(disk->devfs_name, "md/d%d", unit);
+        } else {
+                sprintf(disk->disk_name, "md%d", unit);
+                sprintf(disk->devfs_name, "md/%d", unit);
+        }
+        disk->fops = &md_fops;
+        disk->private_data = mddev;
+        disk->queue = mddev->queue;
+        add_disk(disk);
+        mddev->gendisk = disk;
+        up(&disks_sem);
+        return NULL;
+}
+
+void md_wakeup_thread(mdk_thread_t *thread);
+
+static void md_safemode_timeout(unsigned long data)
+{
+        mddev_t *mddev = (mddev_t *) data;
+
+        mddev->safemode = 1;
+        md_wakeup_thread(mddev->thread);
+}
+
+
+static int do_md_run(mddev_t * mddev)
+{
+        int pnum, err;
+        int chunk_size;
+        struct list_head *tmp;
+        mdk_rdev_t *rdev;
+        struct gendisk *disk;
+        char b[BDEVNAME_SIZE];
+
+        if (list_empty(&mddev->disks)) {
+                MD_BUG();
+                return -EINVAL;
+        }
+
+        if (mddev->pers)
+                return -EBUSY;
+
+        /*
+         * Analyze all RAID superblock(s)
+         */
+        if (!mddev->raid_disks && analyze_sbs(mddev)) {
+                MD_BUG();
+                return -EINVAL;
+        }
+
+        chunk_size = mddev->chunk_size;
+        pnum = level_to_pers(mddev->level);
+
+        if ((pnum != MULTIPATH) && (pnum != RAID1)) {
+                if (!chunk_size) {
+                        /*
+                         * 'default chunksize' in the old md code used to
+                         * be PAGE_SIZE, baaad.
+                         * we abort here to be on the safe side. We don't
+                         * want to continue the bad practice.
+                         */
+                        printk(KERN_ERR 
+                                "no chunksize specified, see 'man raidtab'\n");
+                        return -EINVAL;
+                }
+                if (chunk_size > MAX_CHUNK_SIZE) {
+                        printk(KERN_ERR "too big chunk_size: %d > %d\n",
+                                chunk_size, MAX_CHUNK_SIZE);
+                        return -EINVAL;
+                }
+                /*
+                 * chunk-size has to be a power of 2 and multiples of PAGE_SIZE
+                 */
+                if ( (1 << ffz(~chunk_size)) != chunk_size) {
+                        MD_BUG();
+                        return -EINVAL;
+                }
+                if (chunk_size < PAGE_SIZE) {
+                        printk(KERN_ERR "too small chunk_size: %d < %ld\n",
+                                chunk_size, PAGE_SIZE);
+                        return -EINVAL;
+                }
+
+                /* devices must have minimum size of one chunk */
+                ITERATE_RDEV(mddev,rdev,tmp) {
+                        if (rdev->faulty)
+                                continue;
+                        if (rdev->size < chunk_size / 1024) {
+                                printk(KERN_WARNING
+                                        "md: Dev %s smaller than chunk_size:"
+                                        " %lluk < %dk\n",
+                                        bdevname(rdev->bdev,b),
+                                        (unsigned long long)rdev->size,
+                                        chunk_size / 1024);
+                                return -EINVAL;
+                        }
+                }
+        }
+
+        if (pnum >= MAX_PERSONALITY) {
+                MD_BUG();
+                return -EINVAL;
+        }
+
+#ifdef CONFIG_KMOD
+        if (!pers[pnum])
+        {
+                request_module("md-personality-%d", pnum);
+        }
+#endif
+
+        /*
+         * Drop all container device buffers, from now on
+         * the only valid external interface is through the md
+         * device.
+         * Also find largest hardsector size
+         */
+        ITERATE_RDEV(mddev,rdev,tmp) {
+                if (rdev->faulty)
+                        continue;
+                sync_blockdev(rdev->bdev);
+                invalidate_bdev(rdev->bdev, 0);
+        }
+
+        md_probe(mddev->unit, NULL, NULL);
+        disk = mddev->gendisk;
+        if (!disk)
+                return -ENOMEM;
+
+        spin_lock(&pers_lock);
+        if (!pers[pnum] || !try_module_get(pers[pnum]->owner)) {
+                spin_unlock(&pers_lock);
+                printk(KERN_WARNING "md: personality %d is not loaded!\n",
+                       pnum);
+                return -EINVAL;
+        }
+
+        mddev->pers = pers[pnum];
+        spin_unlock(&pers_lock);
+
+        mddev->resync_max_sectors = mddev->size << 1; /* may be over-ridden by personality */
+
+        err = mddev->pers->run(mddev);
+        if (err) {
+                printk(KERN_ERR "md: pers->run() failed ...\n");
+                module_put(mddev->pers->owner);
+                mddev->pers = NULL;
+                return -EINVAL;
+        }
+        atomic_set(&mddev->writes_pending,0);
+        mddev->safemode = 0;
+        mddev->safemode_timer.function = md_safemode_timeout;
+        mddev->safemode_timer.data = (unsigned long) mddev;
+        mddev->safemode_delay = (20 * HZ)/1000 +1; /* 20 msec delay */
+        mddev->in_sync = 1;
+        
+        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
+        
+        if (mddev->sb_dirty)
+                md_update_sb(mddev);
+
+        set_capacity(disk, mddev->array_size<<1);
+
+        /* If we call blk_queue_make_request here, it will
+         * re-initialise max_sectors etc which may have been
+         * refined inside -> run.  So just set the bits we need to set.
+         * Most initialisation happended when we called
+         * blk_queue_make_request(..., md_fail_request)
+         * earlier.
+         */
+        mddev->queue->queuedata = mddev;
+        mddev->queue->make_request_fn = mddev->pers->make_request;
+
+        mddev->changed = 1;
+        return 0;
+}
+
+static int restart_array(mddev_t *mddev)
+{
+        struct gendisk *disk = mddev->gendisk;
+        int err;
+
+        /*
+         * Complain if it has no devices
+         */
+        err = -ENXIO;
+        if (list_empty(&mddev->disks))
+                goto out;
+
+        if (mddev->pers) {
+                err = -EBUSY;
+                if (!mddev->ro)
+                        goto out;
+
+                mddev->safemode = 0;
+                mddev->ro = 0;
+                set_disk_ro(disk, 0);
+
+                printk(KERN_INFO "md: %s switched to read-write mode.\n",
+                        mdname(mddev));
+                /*
+                 * Kick recovery or resync if necessary
+                 */
+                set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
+                md_wakeup_thread(mddev->thread);
+                err = 0;
+        } else {
+                printk(KERN_ERR "md: %s has no personality assigned.\n",
+                        mdname(mddev));
+                err = -EINVAL;
+        }
+
+out:
+        return err;
+}
+
+static int do_md_stop(mddev_t * mddev, int ro)
+{
+        int err = 0;
+        struct gendisk *disk = mddev->gendisk;
+
+        if (mddev->pers) {
+                if (atomic_read(&mddev->active)>2) {
+                        printk("md: %s still in use.\n",mdname(mddev));
+                        return -EBUSY;
+                }
+
+                if (mddev->sync_thread) {
+                        set_bit(MD_RECOVERY_INTR, &mddev->recovery);
+                        md_unregister_thread(mddev->sync_thread);
+                        mddev->sync_thread = NULL;
+                }
+
+                del_timer_sync(&mddev->safemode_timer);
+
+                invalidate_partition(disk, 0);
+
+                if (ro) {
+                        err  = -ENXIO;
+                        if (mddev->ro)
+                                goto out;
+                        mddev->ro = 1;
+                } else {
+                        if (mddev->ro)
+                                set_disk_ro(disk, 0);
+                        blk_queue_make_request(mddev->queue, md_fail_request);
+                        mddev->pers->stop(mddev);
+                        module_put(mddev->pers->owner);
+                        mddev->pers = NULL;
+                        if (mddev->ro)
+                                mddev->ro = 0;
+                }
+                if (!mddev->in_sync) {
+                        /* mark array as shutdown cleanly */
+                        mddev->in_sync = 1;
+                        md_update_sb(mddev);
+                }
+                if (ro)
+                        set_disk_ro(disk, 1);
+        }
+        /*
+         * Free resources if final stop
+         */
+        if (!ro) {
+                struct gendisk *disk;
+                printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
+
+                export_array(mddev);
+
+                mddev->array_size = 0;
+                disk = mddev->gendisk;
+                if (disk)
+                        set_capacity(disk, 0);
+                mddev->changed = 1;
+        } else
+                printk(KERN_INFO "md: %s switched to read-only mode.\n",
+                        mdname(mddev));
+        err = 0;
+out:
+        return err;
+}
+
+static void autorun_array(mddev_t *mddev)
+{
+        mdk_rdev_t *rdev;
+        struct list_head *tmp;
+        int err;
+
+        if (list_empty(&mddev->disks)) {
+                MD_BUG();
+                return;
+        }
+
+        printk(KERN_INFO "md: running: ");
+
+        ITERATE_RDEV(mddev,rdev,tmp) {
+                char b[BDEVNAME_SIZE];
+                printk("<%s>", bdevname(rdev->bdev,b));
+        }
+        printk("\n");
+
+        err = do_md_run (mddev);
+        if (err) {
+                printk(KERN_WARNING "md: do_md_run() returned %d\n", err);
+                do_md_stop (mddev, 0);
+        }
+}
+
+/*
+ * lets try to run arrays based on all disks that have arrived
+ * until now. (those are in pending_raid_disks)
+ *
+ * the method: pick the first pending disk, collect all disks with
+ * the same UUID, remove all from the pending list and put them into
+ * the 'same_array' list. Then order this list based on superblock
+ * update time (freshest comes first), kick out 'old' disks and
+ * compare superblocks. If everything's fine then run it.
+ *
+ * If "unit" is allocated, then bump its reference count
+ */
+static void autorun_devices(int part)
+{
+        struct list_head candidates;
+        struct list_head *tmp;
+        mdk_rdev_t *rdev0, *rdev;
+        mddev_t *mddev;
+        char b[BDEVNAME_SIZE];
+
+        printk(KERN_INFO "md: autorun ...\n");
+        while (!list_empty(&pending_raid_disks)) {
+                dev_t dev;
+                rdev0 = list_entry(pending_raid_disks.next,
+                                         mdk_rdev_t, same_set);
+
+                printk(KERN_INFO "md: considering %s ...\n",
+                        bdevname(rdev0->bdev,b));
+                INIT_LIST_HEAD(&candidates);
+                ITERATE_RDEV_PENDING(rdev,tmp)
+                        if (super_90_load(rdev, rdev0, 0) >= 0) {
+                                printk(KERN_INFO "md:  adding %s ...\n",
+                                        bdevname(rdev->bdev,b));
+                                list_move(&rdev->same_set, &candidates);
+                        }
+                /*
+                 * now we have a set of devices, with all of them having
+                 * mostly sane superblocks. It's time to allocate the
+                 * mddev.
+                 */
+                if (rdev0->preferred_minor < 0 || rdev0->preferred_minor >= MAX_MD_DEVS) {
+                        printk(KERN_INFO "md: unit number in %s is bad: %d\n",
+                               bdevname(rdev0->bdev, b), rdev0->preferred_minor);
+                        break;
+                }
+                if (part)
+                        dev = MKDEV(mdp_major,
+                                    rdev0->preferred_minor << MdpMinorShift);
+                else
+                        dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
+
+                md_probe(dev, NULL, NULL);
+                mddev = mddev_find(dev);
+                if (!mddev) {
+                        printk(KERN_ERR 
+                                "md: cannot allocate memory for md drive.\n");
+                        break;
+                }
+                if (mddev_lock(mddev)) 
+                        printk(KERN_WARNING "md: %s locked, cannot run\n",
+                               mdname(mddev));
+                else if (mddev->raid_disks || mddev->major_version
+                         || !list_empty(&mddev->disks)) {
+                        printk(KERN_WARNING 
+                                "md: %s already running, cannot run %s\n",
+                                mdname(mddev), bdevname(rdev0->bdev,b));
+                        mddev_unlock(mddev);
+                } else {
+                        printk(KERN_INFO "md: created %s\n", mdname(mddev));
+                        ITERATE_RDEV_GENERIC(candidates,rdev,tmp) {
+                                list_del_init(&rdev->same_set);
+                                if (bind_rdev_to_array(rdev, mddev))
+                                        export_rdev(rdev);
+                        }
+                        autorun_array(mddev);
+                        mddev_unlock(mddev);
+                }
+                /* on success, candidates will be empty, on error
+                 * it won't...
+                 */
+                ITERATE_RDEV_GENERIC(candidates,rdev,tmp)
+                        export_rdev(rdev);
+                mddev_put(mddev);
+        }
+        printk(KERN_INFO "md: ... autorun DONE.\n");
+}
+
+/*
+ * import RAID devices based on one partition
+ * if possible, the array gets run as well.
+ */
+
+static int autostart_array(dev_t startdev)
+{
+        char b[BDEVNAME_SIZE];
+        int err = -EINVAL, i;
+        mdp_super_t *sb = NULL;
+        mdk_rdev_t *start_rdev = NULL, *rdev;
+
+        start_rdev = md_import_device(startdev, 0, 0);
+        if (IS_ERR(start_rdev))
+                return err;
+
+
+        /* NOTE: this can only work for 0.90.0 superblocks */
+        sb = (mdp_super_t*)page_address(start_rdev->sb_page);
+        if (sb->major_version != 0 ||
+            sb->minor_version != 90 ) {
+                printk(KERN_WARNING "md: can only autostart 0.90.0 arrays\n");
+                export_rdev(start_rdev);
+                return err;
+        }
+
+        if (start_rdev->faulty) {
+                printk(KERN_WARNING 
+                        "md: can not autostart based on faulty %s!\n",
+                        bdevname(start_rdev->bdev,b));
+                export_rdev(start_rdev);
+                return err;
+        }
+        list_add(&start_rdev->same_set, &pending_raid_disks);
+
+        for (i = 0; i < MD_SB_DISKS; i++) {
+                mdp_disk_t *desc = sb->disks + i;
+                dev_t dev = MKDEV(desc->major, desc->minor);
+
+                if (!dev)
+                        continue;
+                if (dev == startdev)
+                        continue;
+                if (MAJOR(dev) != desc->major || MINOR(dev) != desc->minor)
+                        continue;
+                rdev = md_import_device(dev, 0, 0);
+                if (IS_ERR(rdev))
+                        continue;
+
+                list_add(&rdev->same_set, &pending_raid_disks);
+        }
+
+        /*
+         * possibly return codes
+         */
+        autorun_devices(0);
+        return 0;
+
+}
+
+
+static int get_version(void __user * arg)
+{
+        mdu_version_t ver;
+
+        ver.major = MD_MAJOR_VERSION;
+        ver.minor = MD_MINOR_VERSION;
+        ver.patchlevel = MD_PATCHLEVEL_VERSION;
+
+        if (copy_to_user(arg, &ver, sizeof(ver)))
+                return -EFAULT;
+
+        return 0;
+}
+
+static int get_array_info(mddev_t * mddev, void __user * arg)
+{
+        mdu_array_info_t info;
+        int nr,working,active,failed,spare;
+        mdk_rdev_t *rdev;
+        struct list_head *tmp;
+
+        nr=working=active=failed=spare=0;
+        ITERATE_RDEV(mddev,rdev,tmp) {
+                nr++;
+                if (rdev->faulty)
+                        failed++;
+                else {
+                        working++;
+                        if (rdev->in_sync)
+                                active++;       
+                        else
+                                spare++;
+                }
+        }
+
+        info.major_version = mddev->major_version;
+        info.minor_version = mddev->minor_version;
+        info.patch_version = MD_PATCHLEVEL_VERSION;
+        info.ctime         = mddev->ctime;
+        info.level         = mddev->level;
+        info.size          = mddev->size;
+        info.nr_disks      = nr;
+        info.raid_disks    = mddev->raid_disks;
+        info.md_minor      = mddev->md_minor;
+        info.not_persistent= !mddev->persistent;
+
+        info.utime         = mddev->utime;
+        info.state         = 0;
+        if (mddev->in_sync)
+                info.state = (1<<MD_SB_CLEAN);
+        info.active_disks  = active;
+        info.working_disks = working;
+        info.failed_disks  = failed;
+        info.spare_disks   = spare;
+
+        info.layout        = mddev->layout;
+        info.chunk_size    = mddev->chunk_size;
+
+        if (copy_to_user(arg, &info, sizeof(info)))
+                return -EFAULT;
+
+        return 0;
+}
+
+static int get_disk_info(mddev_t * mddev, void __user * arg)
+{
+        mdu_disk_info_t info;
+        unsigned int nr;
+        mdk_rdev_t *rdev;
+
+        if (copy_from_user(&info, arg, sizeof(info)))
+                return -EFAULT;
+
+        nr = info.number;
+
+        rdev = find_rdev_nr(mddev, nr);
+        if (rdev) {
+                info.major = MAJOR(rdev->bdev->bd_dev);
+                info.minor = MINOR(rdev->bdev->bd_dev);
+                info.raid_disk = rdev->raid_disk;
+                info.state = 0;
+                if (rdev->faulty)
+                        info.state |= (1<<MD_DISK_FAULTY);
+                else if (rdev->in_sync) {
+                        info.state |= (1<<MD_DISK_ACTIVE);
+                        info.state |= (1<<MD_DISK_SYNC);
+                }
+        } else {
+                info.major = info.minor = 0;
+                info.raid_disk = -1;
+                info.state = (1<<MD_DISK_REMOVED);
+        }
+
+        if (copy_to_user(arg, &info, sizeof(info)))
+                return -EFAULT;
+
+        return 0;
+}
+
+static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
+{
+        char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
+        mdk_rdev_t *rdev;
+        dev_t dev = MKDEV(info->major,info->minor);
+
+        if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
+                return -EOVERFLOW;
+
+        if (!mddev->raid_disks) {
+                int err;
+                /* expecting a device which has a superblock */
+                rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
+                if (IS_ERR(rdev)) {
+                        printk(KERN_WARNING 
+                                "md: md_import_device returned %ld\n",
+                                PTR_ERR(rdev));
+                        return PTR_ERR(rdev);
+                }
+                if (!list_empty(&mddev->disks)) {
+                        mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
+                                                        mdk_rdev_t, same_set);
+                        int err = super_types[mddev->major_version]
+                                .load_super(rdev, rdev0, mddev->minor_version);
+                        if (err < 0) {
+                                printk(KERN_WARNING 
+                                        "md: %s has different UUID to %s\n",
+                                        bdevname(rdev->bdev,b), 
+                                        bdevname(rdev0->bdev,b2));
+                                export_rdev(rdev);
+                                return -EINVAL;
+                        }
+                }
+                err = bind_rdev_to_array(rdev, mddev);
+                if (err)
+                        export_rdev(rdev);
+                return err;
+        }
+
+        /*
+         * add_new_disk can be used once the array is assembled
+         * to add "hot spares".  They must already have a superblock
+         * written
+         */
+        if (mddev->pers) {
+                int err;
+                if (!mddev->pers->hot_add_disk) {
+                        printk(KERN_WARNING 
+                                "%s: personality does not support diskops!\n",
+                               mdname(mddev));
+                        return -EINVAL;
+                }
+                rdev = md_import_device(dev, mddev->major_version,
+                                        mddev->minor_version);
+                if (IS_ERR(rdev)) {
+                        printk(KERN_WARNING 
+                                "md: md_import_device returned %ld\n",
+                                PTR_ERR(rdev));
+                        return PTR_ERR(rdev);
+                }
+                rdev->in_sync = 0; /* just to be sure */
+                rdev->raid_disk = -1;
+                err = bind_rdev_to_array(rdev, mddev);
+                if (err)
+                        export_rdev(rdev);
+                if (mddev->thread)
+                        md_wakeup_thread(mddev->thread);
+                return err;
+        }
+
+        /* otherwise, add_new_disk is only allowed
+         * for major_version==0 superblocks
+         */
+        if (mddev->major_version != 0) {
+                printk(KERN_WARNING "%s: ADD_NEW_DISK not supported\n",
+                       mdname(mddev));
+                return -EINVAL;
+        }
+
+        if (!(info->state & (1<<MD_DISK_FAULTY))) {
+                int err;
+                rdev = md_import_device (dev, -1, 0);
+                if (IS_ERR(rdev)) {
+                        printk(KERN_WARNING 
+                                "md: error, md_import_device() returned %ld\n",
+                                PTR_ERR(rdev));
+                        return PTR_ERR(rdev);
+                }
+                rdev->desc_nr = info->number;
+                if (info->raid_disk < mddev->raid_disks)
+                        rdev->raid_disk = info->raid_disk;
+                else
+                        rdev->raid_disk = -1;
+
+                rdev->faulty = 0;
+                if (rdev->raid_disk < mddev->raid_disks)
+                        rdev->in_sync = (info->state & (1<<MD_DISK_SYNC));
+                else
+                        rdev->in_sync = 0;
+
+                err = bind_rdev_to_array(rdev, mddev);
+                if (err) {
+                        export_rdev(rdev);
+                        return err;
+                }
+
+                if (!mddev->persistent) {
+                        printk(KERN_INFO "md: nonpersistent superblock ...\n");
+                        rdev->sb_offset = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
+                } else 
+                        rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
+                rdev->size = calc_dev_size(rdev, mddev->chunk_size);
+
+                if (!mddev->size || (mddev->size > rdev->size))
+                        mddev->size = rdev->size;
+        }
+
+        return 0;
+}
+
+static int hot_remove_disk(mddev_t * mddev, dev_t dev)
+{
+        char b[BDEVNAME_SIZE];
+        mdk_rdev_t *rdev;
+
+        if (!mddev->pers)
+                return -ENODEV;
+
+        rdev = find_rdev(mddev, dev);
+        if (!rdev)
+                return -ENXIO;
+
+        if (rdev->raid_disk >= 0)
+                goto busy;
+
+        kick_rdev_from_array(rdev);
+        md_update_sb(mddev);
+
+        return 0;
+busy:
+        printk(KERN_WARNING "md: cannot remove active disk %s from %s ... \n",
+                bdevname(rdev->bdev,b), mdname(mddev));
+        return -EBUSY;
+}
+
+static int hot_add_disk(mddev_t * mddev, dev_t dev)
+{
+        char b[BDEVNAME_SIZE];
+        int err;
+        unsigned int size;
+        mdk_rdev_t *rdev;
+
+        if (!mddev->pers)
+                return -ENODEV;
+
+        if (mddev->major_version != 0) {
+                printk(KERN_WARNING "%s: HOT_ADD may only be used with"
+                        " version-0 superblocks.\n",
+                        mdname(mddev));
+                return -EINVAL;
+        }
+        if (!mddev->pers->hot_add_disk) {
+                printk(KERN_WARNING 
+                        "%s: personality does not support diskops!\n",
+                        mdname(mddev));
+                return -EINVAL;
+        }
+
+        rdev = md_import_device (dev, -1, 0);
+        if (IS_ERR(rdev)) {
+                printk(KERN_WARNING 
+                        "md: error, md_import_device() returned %ld\n",
+                        PTR_ERR(rdev));
+                return -EINVAL;
+        }
+
+        if (mddev->persistent)
+                rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
+        else
+                rdev->sb_offset =
+                        rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
+
+        size = calc_dev_size(rdev, mddev->chunk_size);
+        rdev->size = size;
+
+        if (size < mddev->size) {
+                printk(KERN_WARNING 
+                        "%s: disk size %llu blocks < array size %llu\n",
+                        mdname(mddev), (unsigned long long)size,
+                        (unsigned long long)mddev->size);
+                err = -ENOSPC;
+                goto abort_export;
+        }
+
+        if (rdev->faulty) {
+                printk(KERN_WARNING 
+                        "md: can not hot-add faulty %s disk to %s!\n",
+                        bdevname(rdev->bdev,b), mdname(mddev));
+                err = -EINVAL;
+                goto abort_export;
+        }
+        rdev->in_sync = 0;
+        rdev->desc_nr = -1;
+        bind_rdev_to_array(rdev, mddev);
+
+        /*
+         * The rest should better be atomic, we can have disk failures
+         * noticed in interrupt contexts ...
+         */
+
+        if (rdev->desc_nr == mddev->max_disks) {
+                printk(KERN_WARNING "%s: can not hot-add to full array!\n",
+                        mdname(mddev));
+                err = -EBUSY;
+                goto abort_unbind_export;
+        }
+
+        rdev->raid_disk = -1;
+
+        md_update_sb(mddev);
+
+        /*
+         * Kick recovery, maybe this spare has to be added to the
+         * array immediately.
+         */
+        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
+        md_wakeup_thread(mddev->thread);
+
+        return 0;
+
+abort_unbind_export:
+        unbind_rdev_from_array(rdev);
+
+abort_export:
+        export_rdev(rdev);
+        return err;
+}
+
+/*
+ * set_array_info is used two different ways
+ * The original usage is when creating a new array.
+ * In this usage, raid_disks is > 0 and it together with
+ *  level, size, not_persistent,layout,chunksize determine the
+ *  shape of the array.
+ *  This will always create an array with a type-0.90.0 superblock.
+ * The newer usage is when assembling an array.
+ *  In this case raid_disks will be 0, and the major_version field is
+ *  use to determine which style super-blocks are to be found on the devices.
+ *  The minor and patch _version numbers are also kept incase the
+ *  super_block handler wishes to interpret them.
+ */
+static int set_array_info(mddev_t * mddev, mdu_array_info_t *info)
+{
+
+        if (info->raid_disks == 0) {
+                /* just setting version number for superblock loading */
+                if (info->major_version < 0 ||
+                    info->major_version >= sizeof(super_types)/sizeof(super_types[0]) ||
+                    super_types[info->major_version].name == NULL) {
+                        /* maybe try to auto-load a module? */
+                        printk(KERN_INFO 
+                                "md: superblock version %d not known\n",
+                                info->major_version);
+                        return -EINVAL;
+                }
+                mddev->major_version = info->major_version;
+                mddev->minor_version = info->minor_version;
+                mddev->patch_version = info->patch_version;
+                return 0;
+        }
+        mddev->major_version = MD_MAJOR_VERSION;
+        mddev->minor_version = MD_MINOR_VERSION;
+        mddev->patch_version = MD_PATCHLEVEL_VERSION;
+        mddev->ctime         = get_seconds();
+
+        mddev->level         = info->level;
+        mddev->size          = info->size;
+        mddev->raid_disks    = info->raid_disks;
+        /* don't set md_minor, it is determined by which /dev/md* was
+         * openned
+         */
+        if (info->state & (1<<MD_SB_CLEAN))
+                mddev->recovery_cp = MaxSector;
+        else
+                mddev->recovery_cp = 0;
+        mddev->persistent    = ! info->not_persistent;
+
+        mddev->layout        = info->layout;
+        mddev->chunk_size    = info->chunk_size;
+
+        mddev->max_disks     = MD_SB_DISKS;
+
+        mddev->sb_dirty      = 1;
+
+        /*
+         * Generate a 128 bit UUID
+         */
+        get_random_bytes(mddev->uuid, 16);
+
+        return 0;
+}
+
+/*
+ * update_array_info is used to change the configuration of an
+ * on-line array.
+ * The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
+ * fields in the info are checked against the array.
+ * Any differences that cannot be handled will cause an error.
+ * Normally, only one change can be managed at a time.
+ */
+static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
+{
+        int rv = 0;
+        int cnt = 0;
+
+        if (mddev->major_version != info->major_version ||
+            mddev->minor_version != info->minor_version ||
+/*          mddev->patch_version != info->patch_version || */
+            mddev->ctime         != info->ctime         ||
+            mddev->level         != info->level         ||
+/*          mddev->layout        != info->layout        || */
+            !mddev->persistent   != info->not_persistent||
+            mddev->chunk_size    != info->chunk_size    )
+                return -EINVAL;
+        /* Check there is only one change */
+        if (mddev->size != info->size) cnt++;
+        if (mddev->raid_disks != info->raid_disks) cnt++;
+        if (mddev->layout != info->layout) cnt++;
+        if (cnt == 0) return 0;
+        if (cnt > 1) return -EINVAL;
+
+        if (mddev->layout != info->layout) {
+                /* Change layout
+                 * we don't need to do anything at the md level, the
+                 * personality will take care of it all.
+                 */
+                if (mddev->pers->reconfig == NULL)
+                        return -EINVAL;
+                else
+                        return mddev->pers->reconfig(mddev, info->layout, -1);
+        }
+        if (mddev->size != info->size) {
+                mdk_rdev_t * rdev;
+                struct list_head *tmp;
+                if (mddev->pers->resize == NULL)
+                        return -EINVAL;
+                /* The "size" is the amount of each device that is used.
+                 * This can only make sense for arrays with redundancy.
+                 * linear and raid0 always use whatever space is available
+                 * We can only consider changing the size if no resync
+                 * or reconstruction is happening, and if the new size
+                 * is acceptable. It must fit before the sb_offset or,
+                 * if that is <data_offset, it must fit before the
+                 * size of each device.
+                 * If size is zero, we find the largest size that fits.
+                 */
+                if (mddev->sync_thread)
+                        return -EBUSY;
+                ITERATE_RDEV(mddev,rdev,tmp) {
+                        sector_t avail;
+                        int fit = (info->size == 0);
+                        if (rdev->sb_offset > rdev->data_offset)
+                                avail = (rdev->sb_offset*2) - rdev->data_offset;
+                        else
+                                avail = get_capacity(rdev->bdev->bd_disk)
+                                        - rdev->data_offset;
+                        if (fit && (info->size == 0 || info->size > avail/2))
+                                info->size = avail/2;
+                        if (avail < ((sector_t)info->size << 1))
+                                return -ENOSPC;
+                }
+                rv = mddev->pers->resize(mddev, (sector_t)info->size *2);
+                if (!rv) {
+                        struct block_device *bdev;
+
+                        bdev = bdget_disk(mddev->gendisk, 0);
+                        if (bdev) {
+                                down(&bdev->bd_inode->i_sem);
+                                i_size_write(bdev->bd_inode, mddev->array_size << 10);
+                                up(&bdev->bd_inode->i_sem);
+                                bdput(bdev);
+                        }
+                }
+        }
+        if (mddev->raid_disks    != info->raid_disks) {
+                /* change the number of raid disks */
+                if (mddev->pers->reshape == NULL)
+                        return -EINVAL;
+                if (info->raid_disks <= 0 ||
+                    info->raid_disks >= mddev->max_disks)
+                        return -EINVAL;
+                if (mddev->sync_thread)
+                        return -EBUSY;
+                rv = mddev->pers->reshape(mddev, info->raid_disks);
+                if (!rv) {
+                        struct block_device *bdev;
+
+                        bdev = bdget_disk(mddev->gendisk, 0);
+                        if (bdev) {
+                                down(&bdev->bd_inode->i_sem);
+                                i_size_write(bdev->bd_inode, mddev->array_size << 10);
+                                up(&bdev->bd_inode->i_sem);
+                                bdput(bdev);
+                        }
+                }
+        }
+        md_update_sb(mddev);
+        return rv;
+}
+
+static int set_disk_faulty(mddev_t *mddev, dev_t dev)
+{
+        mdk_rdev_t *rdev;
+
+        if (mddev->pers == NULL)
+                return -ENODEV;
+
+        rdev = find_rdev(mddev, dev);
+        if (!rdev)
+                return -ENODEV;
+
+        md_error(mddev, rdev);
+        return 0;
+}
+
+static int md_ioctl(struct inode *inode, struct file *file,
+                        unsigned int cmd, unsigned long arg)
+{
+        int err = 0;
+        void __user *argp = (void __user *)arg;
+        struct hd_geometry __user *loc = argp;
+        mddev_t *mddev = NULL;
+
+        if (!capable(CAP_SYS_ADMIN))
+                return -EACCES;
+
+        /*
+         * Commands dealing with the RAID driver but not any
+         * particular array:
+         */
+        switch (cmd)
+        {
+                case RAID_VERSION:
+                        err = get_version(argp);
+                        goto done;
+
+                case PRINT_RAID_DEBUG:
+                        err = 0;
+                        md_print_devices();
+                        goto done;
+
+#ifndef MODULE
+                case RAID_AUTORUN:
+                        err = 0;
+                        autostart_arrays(arg);
+                        goto done;
+#endif
+                default:;
+        }
+
+        /*
+         * Commands creating/starting a new array:
+         */
+
+        mddev = inode->i_bdev->bd_disk->private_data;
+
+        if (!mddev) {
+                BUG();
+                goto abort;
+        }
+
+
+        if (cmd == START_ARRAY) {
+                /* START_ARRAY doesn't need to lock the array as autostart_array
+                 * does the locking, and it could even be a different array
+                 */
+                static int cnt = 3;
+                if (cnt > 0 ) {
+                        printk(KERN_WARNING
+                               "md: %s(pid %d) used deprecated START_ARRAY ioctl. "
+                               "This will not be supported beyond 2.6\n",
+                               current->comm, current->pid);
+                        cnt--;
+                }
+                err = autostart_array(new_decode_dev(arg));
+                if (err) {
+                        printk(KERN_WARNING "md: autostart failed!\n");
+                        goto abort;
+                }
+                goto done;
+        }
+
+        err = mddev_lock(mddev);
+        if (err) {
+                printk(KERN_INFO 
+                        "md: ioctl lock interrupted, reason %d, cmd %d\n",
+                        err, cmd);
+                goto abort;
+        }
+
+        switch (cmd)
+        {
+                case SET_ARRAY_INFO:
+                        {
+                                mdu_array_info_t info;
+                                if (!arg)
+                                        memset(&info, 0, sizeof(info));
+                                else if (copy_from_user(&info, argp, sizeof(info))) {
+                                        err = -EFAULT;
+                                        goto abort_unlock;
+                                }
+                                if (mddev->pers) {
+                                        err = update_array_info(mddev, &info);
+                                        if (err) {
+                                                printk(KERN_WARNING "md: couldn't update"
+                                                       " array info. %d\n", err);
+                                                goto abort_unlock;
+                                        }
+                                        goto done_unlock;
+                                }
+                                if (!list_empty(&mddev->disks)) {
+                                        printk(KERN_WARNING
+                                               "md: array %s already has disks!\n",
+                                               mdname(mddev));
+                                        err = -EBUSY;
+                                        goto abort_unlock;
+                                }
+                                if (mddev->raid_disks) {
+                                        printk(KERN_WARNING
+                                               "md: array %s already initialised!\n",
+                                               mdname(mddev));
+                                        err = -EBUSY;
+                                        goto abort_unlock;
+                                }
+                                err = set_array_info(mddev, &info);
+                                if (err) {
+                                        printk(KERN_WARNING "md: couldn't set"
+                                               " array info. %d\n", err);
+                                        goto abort_unlock;
+                                }
+                        }
+                        goto done_unlock;
+
+                default:;
+        }
+
+        /*
+         * Commands querying/configuring an existing array:
+         */
+        /* if we are initialised yet, only ADD_NEW_DISK or STOP_ARRAY is allowed */
+        if (!mddev->raid_disks && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY && cmd != RUN_ARRAY) {
+                err = -ENODEV;
+                goto abort_unlock;
+        }
+
+        /*
+         * Commands even a read-only array can execute:
+         */
+        switch (cmd)
+        {
+                case GET_ARRAY_INFO:
+                        err = get_array_info(mddev, argp);
+                        goto done_unlock;
+
+                case GET_DISK_INFO:
+                        err = get_disk_info(mddev, argp);
+                        goto done_unlock;
+
+                case RESTART_ARRAY_RW:
+                        err = restart_array(mddev);
+                        goto done_unlock;
+
+                case STOP_ARRAY:
+                        err = do_md_stop (mddev, 0);
+                        goto done_unlock;
+
+                case STOP_ARRAY_RO:
+                        err = do_md_stop (mddev, 1);
+                        goto done_unlock;
+
+        /*
+         * We have a problem here : there is no easy way to give a CHS
+         * virtual geometry. We currently pretend that we have a 2 heads
+         * 4 sectors (with a BIG number of cylinders...). This drives
+         * dosfs just mad... ;-)
+         */
+                case HDIO_GETGEO:
+                        if (!loc) {
+                                err = -EINVAL;
+                                goto abort_unlock;
+                        }
+                        err = put_user (2, (char __user *) &loc->heads);
+                        if (err)
+                                goto abort_unlock;
+                        err = put_user (4, (char __user *) &loc->sectors);
+                        if (err)
+                                goto abort_unlock;
+                        err = put_user(get_capacity(mddev->gendisk)/8,
+                                        (short __user *) &loc->cylinders);
+                        if (err)
+                                goto abort_unlock;
+                        err = put_user (get_start_sect(inode->i_bdev),
+                                                (long __user *) &loc->start);
+                        goto done_unlock;
+        }
+
+        /*
+         * The remaining ioctls are changing the state of the
+         * superblock, so we do not allow read-only arrays
+         * here:
+         */
+        if (mddev->ro) {
+                err = -EROFS;
+                goto abort_unlock;
+        }
+
+        switch (cmd)
+        {
+                case ADD_NEW_DISK:
+                {
+                        mdu_disk_info_t info;
+                        if (copy_from_user(&info, argp, sizeof(info)))
+                                err = -EFAULT;
+                        else
+                                err = add_new_disk(mddev, &info);
+                        goto done_unlock;
+                }
+
+                case HOT_REMOVE_DISK:
+                        err = hot_remove_disk(mddev, new_decode_dev(arg));
+                        goto done_unlock;
+
+                case HOT_ADD_DISK:
+                        err = hot_add_disk(mddev, new_decode_dev(arg));
+                        goto done_unlock;
+
+                case SET_DISK_FAULTY:
+                        err = set_disk_faulty(mddev, new_decode_dev(arg));
+                        goto done_unlock;
+
+                case RUN_ARRAY:
+                        err = do_md_run (mddev);
+                        goto done_unlock;
+
+                default:
+                        if (_IOC_TYPE(cmd) == MD_MAJOR)
+                                printk(KERN_WARNING "md: %s(pid %d) used"
+                                        " obsolete MD ioctl, upgrade your"
+                                        " software to use new ictls.\n",
+                                        current->comm, current->pid);
+                        err = -EINVAL;
+                        goto abort_unlock;
+        }
+
+done_unlock:
+abort_unlock:
+        mddev_unlock(mddev);
+
+        return err;
+done:
+        if (err)
+                MD_BUG();
+abort:
+        return err;
+}
+
+static int md_open(struct inode *inode, struct file *file)
+{
+        /*
+         * Succeed if we can lock the mddev, which confirms that
+         * it isn't being stopped right now.
+         */
+        mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
+        int err;
+
+        if ((err = mddev_lock(mddev)))
+                goto out;
+
+        err = 0;
+        mddev_get(mddev);
+        mddev_unlock(mddev);
+
+        check_disk_change(inode->i_bdev);
+ out:
+        return err;
+}
+
+static int md_release(struct inode *inode, struct file * file)
+{
+        mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
+
+        if (!mddev)
+                BUG();
+        mddev_put(mddev);
+
+        return 0;
+}
+
+static int md_media_changed(struct gendisk *disk)
+{
+        mddev_t *mddev = disk->private_data;
+
+        return mddev->changed;
+}
+
+static int md_revalidate(struct gendisk *disk)
+{
+        mddev_t *mddev = disk->private_data;
+
+        mddev->changed = 0;
+        return 0;
+}
+static struct block_device_operations md_fops =
+{
+        .owner          = THIS_MODULE,
+        .open           = md_open,
+        .release        = md_release,
+        .ioctl          = md_ioctl,
+        .media_changed  = md_media_changed,
+        .revalidate_disk= md_revalidate,
+};
+
+int md_thread(void * arg)
+{
+        mdk_thread_t *thread = arg;
+
+        lock_kernel();
+
+        /*
+         * Detach thread
+         */
+
+        daemonize(thread->name, mdname(thread->mddev));
+
+        current->exit_signal = SIGCHLD;
+        allow_signal(SIGKILL);
+        thread->tsk = current;
+
+        /*
+         * md_thread is a 'system-thread', it's priority should be very
+         * high. We avoid resource deadlocks individually in each
+         * raid personality. (RAID5 does preallocation) We also use RR and
+         * the very same RT priority as kswapd, thus we will never get
+         * into a priority inversion deadlock.
+         *
+         * we definitely have to have equal or higher priority than
+         * bdflush, otherwise bdflush will deadlock if there are too
+         * many dirty RAID5 blocks.
+         */
+        unlock_kernel();
+
+        complete(thread->event);
+        while (thread->run) {
+                void (*run)(mddev_t *);
+
+                wait_event_interruptible(thread->wqueue,
+                                         test_bit(THREAD_WAKEUP, &thread->flags));
+                if (current->flags & PF_FREEZE)
+                        refrigerator(PF_FREEZE);
+
+                clear_bit(THREAD_WAKEUP, &thread->flags);
+
+                run = thread->run;
+                if (run)
+                        run(thread->mddev);
+
+                if (signal_pending(current))
+                        flush_signals(current);
+        }
+        complete(thread->event);
+        return 0;
+}
+
+void md_wakeup_thread(mdk_thread_t *thread)
+{
+        if (thread) {
+                dprintk("md: waking up MD thread %s.\n", thread->tsk->comm);
+                set_bit(THREAD_WAKEUP, &thread->flags);
+                wake_up(&thread->wqueue);
+        }
+}
+
+mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev,
+                                 const char *name)
+{
+        mdk_thread_t *thread;
+        int ret;
+        struct completion event;
+
+        thread = (mdk_thread_t *) kmalloc
+                                (sizeof(mdk_thread_t), GFP_KERNEL);
+        if (!thread)
+                return NULL;
+
+        memset(thread, 0, sizeof(mdk_thread_t));
+        init_waitqueue_head(&thread->wqueue);
+
+        init_completion(&event);
+        thread->event = &event;
+        thread->run = run;
+        thread->mddev = mddev;
+        thread->name = name;
+        ret = kernel_thread(md_thread, thread, 0);
+        if (ret < 0) {
+                kfree(thread);
+                return NULL;
+        }
+        wait_for_completion(&event);
+        return thread;
+}
+
+static void md_interrupt_thread(mdk_thread_t *thread)
+{
+        if (!thread->tsk) {
+                MD_BUG();
+                return;
+        }
+        dprintk("interrupting MD-thread pid %d\n", thread->tsk->pid);
+        send_sig(SIGKILL, thread->tsk, 1);
+}
+
+void md_unregister_thread(mdk_thread_t *thread)
+{
+        struct completion event;
+
+        init_completion(&event);
+
+        thread->event = &event;
+        thread->run = NULL;
+        thread->name = NULL;
+        md_interrupt_thread(thread);
+        wait_for_completion(&event);
+        kfree(thread);
+}
+
+void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
+{
+        if (!mddev) {
+                MD_BUG();
+                return;
+        }
+
+        if (!rdev || rdev->faulty)
+                return;
+
+        dprintk("md_error dev:%s, rdev:(%d:%d), (caller: %p,%p,%p,%p).\n",
+                mdname(mddev),
+                MAJOR(rdev->bdev->bd_dev), MINOR(rdev->bdev->bd_dev),
+                __builtin_return_address(0),__builtin_return_address(1),
+                __builtin_return_address(2),__builtin_return_address(3));
+
+        if (!mddev->pers->error_handler)
+                return;
+        mddev->pers->error_handler(mddev,rdev);
+        set_bit(MD_RECOVERY_INTR, &mddev->recovery);
+        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
+        md_wakeup_thread(mddev->thread);
+}
+
+/* seq_file implementation /proc/mdstat */
+
+static void status_unused(struct seq_file *seq)
+{
+        int i = 0;
+        mdk_rdev_t *rdev;
+        struct list_head *tmp;
+
+        seq_printf(seq, "unused devices: ");
+
+        ITERATE_RDEV_PENDING(rdev,tmp) {
+                char b[BDEVNAME_SIZE];
+                i++;
+                seq_printf(seq, "%s ",
+                              bdevname(rdev->bdev,b));
+        }
+        if (!i)
+                seq_printf(seq, "<none>");
+
+        seq_printf(seq, "\n");
+}
+
+
+static void status_resync(struct seq_file *seq, mddev_t * mddev)
+{
+        unsigned long max_blocks, resync, res, dt, db, rt;
+
+        resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active))/2;
+
+        if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
+                max_blocks = mddev->resync_max_sectors >> 1;
+        else
+                max_blocks = mddev->size;
+
+        /*
+         * Should not happen.
+         */
+        if (!max_blocks) {
+                MD_BUG();
+                return;
+        }
+        res = (resync/1024)*1000/(max_blocks/1024 + 1);
+        {
+                int i, x = res/50, y = 20-x;
+                seq_printf(seq, "[");
+                for (i = 0; i < x; i++)
+                        seq_printf(seq, "=");
+                seq_printf(seq, ">");
+                for (i = 0; i < y; i++)
+                        seq_printf(seq, ".");
+                seq_printf(seq, "] ");
+        }
+        seq_printf(seq, " %s =%3lu.%lu%% (%lu/%lu)",
+                      (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
+                       "resync" : "recovery"),
+                      res/10, res % 10, resync, max_blocks);
+
+        /*
+         * We do not want to overflow, so the order of operands and
+         * the * 100 / 100 trick are important. We do a +1 to be
+         * safe against division by zero. We only estimate anyway.
+         *
+         * dt: time from mark until now
+         * db: blocks written from mark until now
+         * rt: remaining time
+         */
+        dt = ((jiffies - mddev->resync_mark) / HZ);
+        if (!dt) dt++;
+        db = resync - (mddev->resync_mark_cnt/2);
+        rt = (dt * ((max_blocks-resync) / (db/100+1)))/100;
+
+        seq_printf(seq, " finish=%lu.%lumin", rt / 60, (rt % 60)/6);
+
+        seq_printf(seq, " speed=%ldK/sec", db/dt);
+}
+
+static void *md_seq_start(struct seq_file *seq, loff_t *pos)
+{
+        struct list_head *tmp;
+        loff_t l = *pos;
+        mddev_t *mddev;
+
+        if (l >= 0x10000)
+                return NULL;
+        if (!l--)
+                /* header */
+                return (void*)1;
+
+        spin_lock(&all_mddevs_lock);
+        list_for_each(tmp,&all_mddevs)
+                if (!l--) {
+                        mddev = list_entry(tmp, mddev_t, all_mddevs);
+                        mddev_get(mddev);
+                        spin_unlock(&all_mddevs_lock);
+                        return mddev;
+                }
+        spin_unlock(&all_mddevs_lock);
+        if (!l--)
+                return (void*)2;/* tail */
+        return NULL;
+}
+
+static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+        struct list_head *tmp;
+        mddev_t *next_mddev, *mddev = v;
+        
+        ++*pos;
+        if (v == (void*)2)
+                return NULL;
+
+        spin_lock(&all_mddevs_lock);
+        if (v == (void*)1)
+                tmp = all_mddevs.next;
+        else
+                tmp = mddev->all_mddevs.next;
+        if (tmp != &all_mddevs)
+                next_mddev = mddev_get(list_entry(tmp,mddev_t,all_mddevs));
+        else {
+                next_mddev = (void*)2;
+                *pos = 0x10000;
+        }               
+        spin_unlock(&all_mddevs_lock);
+
+        if (v != (void*)1)
+                mddev_put(mddev);
+        return next_mddev;
+
+}
+
+static void md_seq_stop(struct seq_file *seq, void *v)
+{
+        mddev_t *mddev = v;
+
+        if (mddev && v != (void*)1 && v != (void*)2)
+                mddev_put(mddev);
+}
+
+static int md_seq_show(struct seq_file *seq, void *v)
+{
+        mddev_t *mddev = v;
+        sector_t size;
+        struct list_head *tmp2;
+        mdk_rdev_t *rdev;
+        int i;
+
+        if (v == (void*)1) {
+                seq_printf(seq, "Personalities : ");
+                spin_lock(&pers_lock);
+                for (i = 0; i < MAX_PERSONALITY; i++)
+                        if (pers[i])
+                                seq_printf(seq, "[%s] ", pers[i]->name);
+
+                spin_unlock(&pers_lock);
+                seq_printf(seq, "\n");
+                return 0;
+        }
+        if (v == (void*)2) {
+                status_unused(seq);
+                return 0;
+        }
+
+        if (mddev_lock(mddev)!=0) 
+                return -EINTR;
+        if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
+                seq_printf(seq, "%s : %sactive", mdname(mddev),
+                                                mddev->pers ? "" : "in");
+                if (mddev->pers) {
+                        if (mddev->ro)
+                                seq_printf(seq, " (read-only)");
+                        seq_printf(seq, " %s", mddev->pers->name);
+                }
+
+                size = 0;
+                ITERATE_RDEV(mddev,rdev,tmp2) {
+                        char b[BDEVNAME_SIZE];
+                        seq_printf(seq, " %s[%d]",
+                                bdevname(rdev->bdev,b), rdev->desc_nr);
+                        if (rdev->faulty) {
+                                seq_printf(seq, "(F)");
+                                continue;
+                        }
+                        size += rdev->size;
+                }
+
+                if (!list_empty(&mddev->disks)) {
+                        if (mddev->pers)
+                                seq_printf(seq, "\n      %llu blocks",
+                                        (unsigned long long)mddev->array_size);
+                        else
+                                seq_printf(seq, "\n      %llu blocks",
+                                        (unsigned long long)size);
+                }
+
+                if (mddev->pers) {
+                        mddev->pers->status (seq, mddev);
+                        seq_printf(seq, "\n      ");
+                        if (mddev->curr_resync > 2)
+                                status_resync (seq, mddev);
+                        else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
+                                seq_printf(seq, "       resync=DELAYED");
+                }
+
+                seq_printf(seq, "\n");
+        }
+        mddev_unlock(mddev);
+        
+        return 0;
+}
+
+static struct seq_operations md_seq_ops = {
+        .start  = md_seq_start,
+        .next   = md_seq_next,
+        .stop   = md_seq_stop,
+        .show   = md_seq_show,
+};
+
+static int md_seq_open(struct inode *inode, struct file *file)
+{
+        int error;
+
+        error = seq_open(file, &md_seq_ops);
+        return error;
+}
+
+static struct file_operations md_seq_fops = {
+        .open           = md_seq_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = seq_release,
+};
+
+int register_md_personality(int pnum, mdk_personality_t *p)
+{
+        if (pnum >= MAX_PERSONALITY) {
+                printk(KERN_ERR
+                       "md: tried to install personality %s as nr %d, but max is %lu\n",
+                       p->name, pnum, MAX_PERSONALITY-1);
+                return -EINVAL;
+        }
+
+        spin_lock(&pers_lock);
+        if (pers[pnum]) {
+                spin_unlock(&pers_lock);
+                MD_BUG();
+                return -EBUSY;
+        }
+
+        pers[pnum] = p;
+        printk(KERN_INFO "md: %s personality registered as nr %d\n", p->name, pnum);
+        spin_unlock(&pers_lock);
+        return 0;
+}
+
+int unregister_md_personality(int pnum)
+{
+        if (pnum >= MAX_PERSONALITY) {
+                MD_BUG();
+                return -EINVAL;
+        }
+
+        printk(KERN_INFO "md: %s personality unregistered\n", pers[pnum]->name);
+        spin_lock(&pers_lock);
+        pers[pnum] = NULL;
+        spin_unlock(&pers_lock);
+        return 0;
+}
+
+static int is_mddev_idle(mddev_t *mddev)
+{
+        mdk_rdev_t * rdev;
+        struct list_head *tmp;
+        int idle;
+        unsigned long curr_events;
+
+        idle = 1;
+        ITERATE_RDEV(mddev,rdev,tmp) {
+                struct gendisk *disk = rdev->bdev->bd_contains->bd_disk;
+                curr_events = disk_stat_read(disk, read_sectors) + 
+                                disk_stat_read(disk, write_sectors) - 
+                                atomic_read(&disk->sync_io);
+                /* Allow some slack between valud of curr_events and last_events,
+                 * as there are some uninteresting races.
+                 * Note: the following is an unsigned comparison.
+                 */
+                if ((curr_events - rdev->last_events + 32) > 64) {
+                        rdev->last_events = curr_events;
+                        idle = 0;
+                }
+        }
+        return idle;
+}
+
+void md_done_sync(mddev_t *mddev, int blocks, int ok)
+{
+        /* another "blocks" (512byte) blocks have been synced */
+        atomic_sub(blocks, &mddev->recovery_active);
+        wake_up(&mddev->recovery_wait);
+        if (!ok) {
+                set_bit(MD_RECOVERY_ERR, &mddev->recovery);
+                md_wakeup_thread(mddev->thread);
+                // stop recovery, signal do_sync ....
+        }
+}
+
+
+void md_write_start(mddev_t *mddev)
+{
+        if (!atomic_read(&mddev->writes_pending)) {
+                mddev_lock_uninterruptible(mddev);
+                if (mddev->in_sync) {
+                        mddev->in_sync = 0;
+                        del_timer(&mddev->safemode_timer);
+                        md_update_sb(mddev);
+                }
+                atomic_inc(&mddev->writes_pending);
+                mddev_unlock(mddev);
+        } else
+                atomic_inc(&mddev->writes_pending);
+}
+
+void md_write_end(mddev_t *mddev)
+{
+        if (atomic_dec_and_test(&mddev->writes_pending)) {
+                if (mddev->safemode == 2)
+                        md_wakeup_thread(mddev->thread);
+                else
+                        mod_timer(&mddev->safemode_timer, jiffies + mddev->safemode_delay);
+        }
+}
+
+static inline void md_enter_safemode(mddev_t *mddev)
+{
+        if (!mddev->safemode) return;
+        if (mddev->safemode == 2 &&
+            (atomic_read(&mddev->writes_pending) || mddev->in_sync ||
+                    mddev->recovery_cp != MaxSector))
+                return; /* avoid the lock */
+        mddev_lock_uninterruptible(mddev);
+        if (mddev->safemode && !atomic_read(&mddev->writes_pending) &&
+            !mddev->in_sync && mddev->recovery_cp == MaxSector) {
+                mddev->in_sync = 1;
+                md_update_sb(mddev);
+        }
+        mddev_unlock(mddev);
+
+        if (mddev->safemode == 1)
+                mddev->safemode = 0;
+}
+
+void md_handle_safemode(mddev_t *mddev)
+{
+        if (signal_pending(current)) {
+                printk(KERN_INFO "md: %s in immediate safe mode\n",
+                        mdname(mddev));
+                mddev->safemode = 2;
+                flush_signals(current);
+        }
+        md_enter_safemode(mddev);
+}
+
+
+DECLARE_WAIT_QUEUE_HEAD(resync_wait);
+
+#define SYNC_MARKS      10
+#define SYNC_MARK_STEP  (3*HZ)
+static void md_do_sync(mddev_t *mddev)
+{
+        mddev_t *mddev2;
+        unsigned int currspeed = 0,
+                 window;
+        sector_t max_sectors,j;
+        unsigned long mark[SYNC_MARKS];
+        sector_t mark_cnt[SYNC_MARKS];
+        int last_mark,m;
+        struct list_head *tmp;
+        sector_t last_check;
+
+        /* just incase thread restarts... */
+        if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
+                return;
+
+        /* we overload curr_resync somewhat here.
+         * 0 == not engaged in resync at all
+         * 2 == checking that there is no conflict with another sync
+         * 1 == like 2, but have yielded to allow conflicting resync to
+         *              commense
+         * other == active in resync - this many blocks
+         *
+         * Before starting a resync we must have set curr_resync to
+         * 2, and then checked that every "conflicting" array has curr_resync
+         * less than ours.  When we find one that is the same or higher
+         * we wait on resync_wait.  To avoid deadlock, we reduce curr_resync
+         * to 1 if we choose to yield (based arbitrarily on address of mddev structure).
+         * This will mean we have to start checking from the beginning again.
+         *
+         */
+
+        do {
+                mddev->curr_resync = 2;
+
+        try_again:
+                if (signal_pending(current)) {
+                        flush_signals(current);
+                        goto skip;
+                }
+                ITERATE_MDDEV(mddev2,tmp) {
+                        printk(".");
+                        if (mddev2 == mddev)
+                                continue;
+                        if (mddev2->curr_resync && 
+                            match_mddev_units(mddev,mddev2)) {
+                                DEFINE_WAIT(wq);
+                                if (mddev < mddev2 && mddev->curr_resync == 2) {
+                                        /* arbitrarily yield */
+                                        mddev->curr_resync = 1;
+                                        wake_up(&resync_wait);
+                                }
+                                if (mddev > mddev2 && mddev->curr_resync == 1)
+                                        /* no need to wait here, we can wait the next
+                                         * time 'round when curr_resync == 2
+                                         */
+                                        continue;
+                                prepare_to_wait(&resync_wait, &wq, TASK_INTERRUPTIBLE);
+                                if (!signal_pending(current)
+                                    && mddev2->curr_resync >= mddev->curr_resync) {
+                                        printk(KERN_INFO "md: delaying resync of %s"
+                                               " until %s has finished resync (they"
+                                               " share one or more physical units)\n",
+                                               mdname(mddev), mdname(mddev2));
+                                        mddev_put(mddev2);
+                                        schedule();
+                                        finish_wait(&resync_wait, &wq);
+                                        goto try_again;
+                                }
+                                finish_wait(&resync_wait, &wq);
+                        }
+                }
+        } while (mddev->curr_resync < 2);
+
+        if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
+                /* resync follows the size requested by the personality,
+                 * which default to physical size, but can be virtual size
+                 */
+                max_sectors = mddev->resync_max_sectors;
+        else
+                /* recovery follows the physical size of devices */
+                max_sectors = mddev->size << 1;
+
+        printk(KERN_INFO "md: syncing RAID array %s\n", mdname(mddev));
+        printk(KERN_INFO "md: minimum _guaranteed_ reconstruction speed:"
+                " %d KB/sec/disc.\n", sysctl_speed_limit_min);
+        printk(KERN_INFO "md: using maximum available idle IO bandwith "
+               "(but not more than %d KB/sec) for reconstruction.\n",
+               sysctl_speed_limit_max);
+
+        is_mddev_idle(mddev); /* this also initializes IO event counters */
+        if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
+                j = mddev->recovery_cp;
+        else
+                j = 0;
+        for (m = 0; m < SYNC_MARKS; m++) {
+                mark[m] = jiffies;
+                mark_cnt[m] = j;
+        }
+        last_mark = 0;
+        mddev->resync_mark = mark[last_mark];
+        mddev->resync_mark_cnt = mark_cnt[last_mark];
+
+        /*
+         * Tune reconstruction:
+         */
+        window = 32*(PAGE_SIZE/512);
+        printk(KERN_INFO "md: using %dk window, over a total of %llu blocks.\n",
+                window/2,(unsigned long long) max_sectors/2);
+
+        atomic_set(&mddev->recovery_active, 0);
+        init_waitqueue_head(&mddev->recovery_wait);
+        last_check = 0;
+
+        if (j>2) {
+                printk(KERN_INFO 
+                        "md: resuming recovery of %s from checkpoint.\n",
+                        mdname(mddev));
+                mddev->curr_resync = j;
+        }
+
+        while (j < max_sectors) {
+                int sectors;
+
+                sectors = mddev->pers->sync_request(mddev, j, currspeed < sysctl_speed_limit_min);
+                if (sectors < 0) {
+                        set_bit(MD_RECOVERY_ERR, &mddev->recovery);
+                        goto out;
+                }
+                atomic_add(sectors, &mddev->recovery_active);
+                j += sectors;
+                if (j>1) mddev->curr_resync = j;
+
+                if (last_check + window > j || j == max_sectors)
+                        continue;
+
+                last_check = j;
+
+                if (test_bit(MD_RECOVERY_INTR, &mddev->recovery) ||
+                    test_bit(MD_RECOVERY_ERR, &mddev->recovery))
+                        break;
+
+        repeat:
+                if (time_after_eq(jiffies, mark[last_mark] + SYNC_MARK_STEP )) {
+                        /* step marks */
+                        int next = (last_mark+1) % SYNC_MARKS;
+
+                        mddev->resync_mark = mark[next];
+                        mddev->resync_mark_cnt = mark_cnt[next];
+                        mark[next] = jiffies;
+                        mark_cnt[next] = j - atomic_read(&mddev->recovery_active);
+                        last_mark = next;
+                }
+
+
+                if (signal_pending(current)) {
+                        /*
+                         * got a signal, exit.
+                         */
+                        printk(KERN_INFO 
+                                "md: md_do_sync() got signal ... exiting\n");
+                        flush_signals(current);
+                        set_bit(MD_RECOVERY_INTR, &mddev->recovery);
+                        goto out;
+                }
+
+                /*
+                 * this loop exits only if either when we are slower than
+                 * the 'hard' speed limit, or the system was IO-idle for
+                 * a jiffy.
+                 * the system might be non-idle CPU-wise, but we only care
+                 * about not overloading the IO subsystem. (things like an
+                 * e2fsck being done on the RAID array should execute fast)
+                 */
+                mddev->queue->unplug_fn(mddev->queue);
+                cond_resched();
+
+                currspeed = ((unsigned long)(j-mddev->resync_mark_cnt))/2/((jiffies-mddev->resync_mark)/HZ +1) +1;
+
+                if (currspeed > sysctl_speed_limit_min) {
+                        if ((currspeed > sysctl_speed_limit_max) ||
+                                        !is_mddev_idle(mddev)) {
+                                msleep_interruptible(250);
+                                goto repeat;
+                        }
+                }
+        }
+        printk(KERN_INFO "md: %s: sync done.\n",mdname(mddev));
+        /*
+         * this also signals 'finished resyncing' to md_stop
+         */
+ out:
+        mddev->queue->unplug_fn(mddev->queue);
+
+        wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
+
+        /* tell personality that we are finished */
+        mddev->pers->sync_request(mddev, max_sectors, 1);
+
+        if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
+            mddev->curr_resync > 2 &&
+            mddev->curr_resync >= mddev->recovery_cp) {
+                if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
+                        printk(KERN_INFO 
+                                "md: checkpointing recovery of %s.\n",
+                                mdname(mddev));
+                        mddev->recovery_cp = mddev->curr_resync;
+                } else
+                        mddev->recovery_cp = MaxSector;
+        }
+
+        md_enter_safemode(mddev);
+ skip:
+        mddev->curr_resync = 0;
+        wake_up(&resync_wait);
+        set_bit(MD_RECOVERY_DONE, &mddev->recovery);
+        md_wakeup_thread(mddev->thread);
+}
+
+
+/*
+ * This routine is regularly called by all per-raid-array threads to
+ * deal with generic issues like resync and super-block update.
+ * Raid personalities that don't have a thread (linear/raid0) do not
+ * need this as they never do any recovery or update the superblock.
+ *
+ * It does not do any resync itself, but rather "forks" off other threads
+ * to do that as needed.
+ * When it is determined that resync is needed, we set MD_RECOVERY_RUNNING in
+ * "->recovery" and create a thread at ->sync_thread.
+ * When the thread finishes it sets MD_RECOVERY_DONE (and might set MD_RECOVERY_ERR)
+ * and wakeups up this thread which will reap the thread and finish up.
+ * This thread also removes any faulty devices (with nr_pending == 0).
+ *
+ * The overall approach is:
+ *  1/ if the superblock needs updating, update it.
+ *  2/ If a recovery thread is running, don't do anything else.
+ *  3/ If recovery has finished, clean up, possibly marking spares active.
+ *  4/ If there are any faulty devices, remove them.
+ *  5/ If array is degraded, try to add spares devices
+ *  6/ If array has spares or is not in-sync, start a resync thread.
+ */
+void md_check_recovery(mddev_t *mddev)
+{
+        mdk_rdev_t *rdev;
+        struct list_head *rtmp;
+
+
+        dprintk(KERN_INFO "md: recovery thread got woken up ...\n");
+
+        if (mddev->ro)
+                return;
+        if ( ! (
+                mddev->sb_dirty ||
+                test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
+                test_bit(MD_RECOVERY_DONE, &mddev->recovery)
+                ))
+                return;
+        if (mddev_trylock(mddev)==0) {
+                int spares =0;
+                if (mddev->sb_dirty)
+                        md_update_sb(mddev);
+                if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
+                    !test_bit(MD_RECOVERY_DONE, &mddev->recovery)) {
+                        /* resync/recovery still happening */
+                        clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
+                        goto unlock;
+                }
+                if (mddev->sync_thread) {
+                        /* resync has finished, collect result */
+                        md_unregister_thread(mddev->sync_thread);
+                        mddev->sync_thread = NULL;
+                        if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
+                            !test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
+                                /* success...*/
+                                /* activate any spares */
+                                mddev->pers->spare_active(mddev);
+                        }
+                        md_update_sb(mddev);
+                        mddev->recovery = 0;
+                        /* flag recovery needed just to double check */
+                        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
+                        goto unlock;
+                }
+                if (mddev->recovery)
+                        /* probably just the RECOVERY_NEEDED flag */
+                        mddev->recovery = 0;
+
+                /* no recovery is running.
+                 * remove any failed drives, then
+                 * add spares if possible.
+                 * Spare are also removed and re-added, to allow
+                 * the personality to fail the re-add.
+                 */
+                ITERATE_RDEV(mddev,rdev,rtmp)
+                        if (rdev->raid_disk >= 0 &&
+                            (rdev->faulty || ! rdev->in_sync) &&
+                            atomic_read(&rdev->nr_pending)==0) {
+                                if (mddev->pers->hot_remove_disk(mddev, rdev->raid_disk)==0)
+                                        rdev->raid_disk = -1;
+                        }
+
+                if (mddev->degraded) {
+                        ITERATE_RDEV(mddev,rdev,rtmp)
+                                if (rdev->raid_disk < 0
+                                    && !rdev->faulty) {
+                                        if (mddev->pers->hot_add_disk(mddev,rdev))
+                                                spares++;
+                                        else
+                                                break;
+                                }
+                }
+
+                if (!spares && (mddev->recovery_cp == MaxSector )) {
+                        /* nothing we can do ... */
+                        goto unlock;
+                }
+                if (mddev->pers->sync_request) {
+                        set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
+                        if (!spares)
+                                set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
+                        mddev->sync_thread = md_register_thread(md_do_sync,
+                                                                mddev,
+                                                                "%s_resync");
+                        if (!mddev->sync_thread) {
+                                printk(KERN_ERR "%s: could not start resync"
+                                        " thread...\n", 
+                                        mdname(mddev));
+                                /* leave the spares where they are, it shouldn't hurt */
+                                mddev->recovery = 0;
+                        } else {
+                                md_wakeup_thread(mddev->sync_thread);
+                        }
+                }
+        unlock:
+                mddev_unlock(mddev);
+        }
+}
+
+int md_notify_reboot(struct notifier_block *this,
+                                        unsigned long code, void *x)
+{
+        struct list_head *tmp;
+        mddev_t *mddev;
+
+        if ((code == SYS_DOWN) || (code == SYS_HALT) || (code == SYS_POWER_OFF)) {
+
+                printk(KERN_INFO "md: stopping all md devices.\n");
+
+                ITERATE_MDDEV(mddev,tmp)
+                        if (mddev_trylock(mddev)==0)
+                                do_md_stop (mddev, 1);
+                /*
+                 * certain more exotic SCSI devices are known to be
+                 * volatile wrt too early system reboots. While the
+                 * right place to handle this issue is the given
+                 * driver, we do want to have a safe RAID driver ...
+                 */
+                mdelay(1000*1);
+        }
+        return NOTIFY_DONE;
+}
+
+struct notifier_block md_notifier = {
+        .notifier_call  = md_notify_reboot,
+        .next           = NULL,
+        .priority       = INT_MAX, /* before any real devices */
+};
+
+static void md_geninit(void)
+{
+        struct proc_dir_entry *p;
+
+        dprintk("md: sizeof(mdp_super_t) = %d\n", (int)sizeof(mdp_super_t));
+
+        p = create_proc_entry("mdstat", S_IRUGO, NULL);
+        if (p)
+                p->proc_fops = &md_seq_fops;
+}
+
+int __init md_init(void)
+{
+        int minor;
+
+        printk(KERN_INFO "md: md driver %d.%d.%d MAX_MD_DEVS=%d,"
+                        " MD_SB_DISKS=%d\n",
+                        MD_MAJOR_VERSION, MD_MINOR_VERSION,
+                        MD_PATCHLEVEL_VERSION, MAX_MD_DEVS, MD_SB_DISKS);
+
+        if (register_blkdev(MAJOR_NR, "md"))
+                return -1;
+        if ((mdp_major=register_blkdev(0, "mdp"))<=0) {
+                unregister_blkdev(MAJOR_NR, "md");
+                return -1;
+        }
+        devfs_mk_dir("md");
+        blk_register_region(MKDEV(MAJOR_NR, 0), MAX_MD_DEVS, THIS_MODULE,
+                                md_probe, NULL, NULL);
+        blk_register_region(MKDEV(mdp_major, 0), MAX_MD_DEVS<<MdpMinorShift, THIS_MODULE,
+                            md_probe, NULL, NULL);
+
+        for (minor=0; minor < MAX_MD_DEVS; ++minor)
+                devfs_mk_bdev(MKDEV(MAJOR_NR, minor),
+                                S_IFBLK|S_IRUSR|S_IWUSR,
+                                "md/%d", minor);
+
+        for (minor=0; minor < MAX_MD_DEVS; ++minor)
+                devfs_mk_bdev(MKDEV(mdp_major, minor<<MdpMinorShift),
+                              S_IFBLK|S_IRUSR|S_IWUSR,
+                              "md/mdp%d", minor);
+
+
+        register_reboot_notifier(&md_notifier);
+        raid_table_header = register_sysctl_table(raid_root_table, 1);
+
+        md_geninit();
+        return (0);
+}
+
+
+#ifndef MODULE
+
+/*
+ * Searches all registered partitions for autorun RAID arrays
+ * at boot time.
+ */
+static dev_t detected_devices[128];
+static int dev_cnt;
+
+void md_autodetect_dev(dev_t dev)
+{
+        if (dev_cnt >= 0 && dev_cnt < 127)
+                detected_devices[dev_cnt++] = dev;
+}
+
+
+static void autostart_arrays(int part)
+{
+        mdk_rdev_t *rdev;
+        int i;
+
+        printk(KERN_INFO "md: Autodetecting RAID arrays.\n");
+
+        for (i = 0; i < dev_cnt; i++) {
+                dev_t dev = detected_devices[i];
+
+                rdev = md_import_device(dev,0, 0);
+                if (IS_ERR(rdev))
+                        continue;
+
+                if (rdev->faulty) {
+                        MD_BUG();
+                        continue;
+                }
+                list_add(&rdev->same_set, &pending_raid_disks);
+        }
+        dev_cnt = 0;
+
+        autorun_devices(part);
+}
+
+#endif
+
+static __exit void md_exit(void)
+{
+        mddev_t *mddev;
+        struct list_head *tmp;
+        int i;
+        blk_unregister_region(MKDEV(MAJOR_NR,0), MAX_MD_DEVS);
+        blk_unregister_region(MKDEV(mdp_major,0), MAX_MD_DEVS << MdpMinorShift);
+        for (i=0; i < MAX_MD_DEVS; i++)
+                devfs_remove("md/%d", i);
+        for (i=0; i < MAX_MD_DEVS; i++)
+                devfs_remove("md/d%d", i);
+
+        devfs_remove("md");
+
+        unregister_blkdev(MAJOR_NR,"md");
+        unregister_blkdev(mdp_major, "mdp");
+        unregister_reboot_notifier(&md_notifier);
+        unregister_sysctl_table(raid_table_header);
+        remove_proc_entry("mdstat", NULL);
+        ITERATE_MDDEV(mddev,tmp) {
+                struct gendisk *disk = mddev->gendisk;
+                if (!disk)
+                        continue;
+                export_array(mddev);
+                del_gendisk(disk);
+                put_disk(disk);
+                mddev->gendisk = NULL;
+                mddev_put(mddev);
+        }
+}
+
+module_init(md_init)
+module_exit(md_exit)
+
+EXPORT_SYMBOL(register_md_personality);
+EXPORT_SYMBOL(unregister_md_personality);
+EXPORT_SYMBOL(md_error);
+EXPORT_SYMBOL(md_done_sync);
+EXPORT_SYMBOL(md_write_start);
+EXPORT_SYMBOL(md_write_end);
+EXPORT_SYMBOL(md_handle_safemode);
+EXPORT_SYMBOL(md_register_thread);
+EXPORT_SYMBOL(md_unregister_thread);
+EXPORT_SYMBOL(md_wakeup_thread);
+EXPORT_SYMBOL(md_print_devices);
+EXPORT_SYMBOL(md_check_recovery);
+MODULE_LICENSE("GPL");