1 files changed, 550 insertions, 84 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index f19b874753a9..306268ec99ff 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -44,6 +44,7 @@
 #include <linux/suspend.h>
 #include <linux/poll.h>
 #include <linux/mutex.h>
+#include <linux/ctype.h>
 
 #include <linux/init.h>
 
@@ -72,6 +73,10 @@ static void autostart_arrays (int part);
 static LIST_HEAD(pers_list);
 static DEFINE_SPINLOCK(pers_lock);
 
+static void md_print_devices(void);
+
+#define MD_BUG(x...) { printk("md: bug in file %s, line %d\n", __FILE__, __LINE__); md_print_devices(); }
+
 /*
  * 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.
@@ -170,7 +175,7 @@ EXPORT_SYMBOL_GPL(md_new_event);
 /* Alternate version that can be called from interrupts
  * when calling sysfs_notify isn't needed.
  */
-void md_new_event_inintr(mddev_t *mddev)
+static void md_new_event_inintr(mddev_t *mddev)
 {
         atomic_inc(&md_event_count);
         wake_up(&md_event_waiters);
@@ -732,6 +737,7 @@ 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);
+        __u64 ev1 = md_event(sb);
 
         rdev->raid_disk = -1;
         rdev->flags = 0;
@@ -748,7 +754,7 @@ static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
                 mddev->layout = sb->layout;
                 mddev->raid_disks = sb->raid_disks;
                 mddev->size = sb->size;
-                mddev->events = md_event(sb);
+                mddev->events = ev1;
                 mddev->bitmap_offset = 0;
                 mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
 
@@ -797,7 +803,6 @@ static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
 
         } else if (mddev->pers == NULL) {
                 /* Insist on good event counter while assembling */
-                __u64 ev1 = md_event(sb);
                 ++ev1;
                 if (ev1 < mddev->events) 
                         return -EINVAL;
@@ -805,19 +810,21 @@ static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
                 /* if adding to array with a bitmap, then we can accept an
                  * older device ... but not too old.
                  */
-                __u64 ev1 = md_event(sb);
                 if (ev1 < mddev->bitmap->events_cleared)
                         return 0;
-        } else /* just a hot-add of a new device, leave raid_disk at -1 */
-                return 0;
+        } else {
+                if (ev1 < mddev->events)
+                        /* just a hot-add of a new device, leave raid_disk at -1 */
+                        return 0;
+        }
 
         if (mddev->level != LEVEL_MULTIPATH) {
                 desc = sb->disks + rdev->desc_nr;
 
                 if (desc->state & (1<<MD_DISK_FAULTY))
                         set_bit(Faulty, &rdev->flags);
-                else if (desc->state & (1<<MD_DISK_SYNC) &&
-                         desc->raid_disk < mddev->raid_disks) {
+                else if (desc->state & (1<<MD_DISK_SYNC) /* &&
+                            desc->raid_disk < mddev->raid_disks */) {
                         set_bit(In_sync, &rdev->flags);
                         rdev->raid_disk = desc->raid_disk;
                 }
@@ -1100,6 +1107,7 @@ static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
 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);
+        __u64 ev1 = le64_to_cpu(sb->events);
 
         rdev->raid_disk = -1;
         rdev->flags = 0;
@@ -1115,7 +1123,7 @@ static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
                 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->events = ev1;
                 mddev->bitmap_offset = 0;
                 mddev->default_bitmap_offset = 1024 >> 9;
                 
@@ -1149,7 +1157,6 @@ static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
 
         } else if (mddev->pers == NULL) {
                 /* Insist of good event counter while assembling */
-                __u64 ev1 = le64_to_cpu(sb->events);
                 ++ev1;
                 if (ev1 < mddev->events)
                         return -EINVAL;
@@ -1157,12 +1164,13 @@ static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
                 /* If adding to array with a bitmap, then we can accept an
                  * older device, but not too old.
                  */
-                __u64 ev1 = le64_to_cpu(sb->events);
                 if (ev1 < mddev->bitmap->events_cleared)
                         return 0;
-        } else /* just a hot-add of a new device, leave raid_disk at -1 */
-                return 0;
-
+        } else {
+                if (ev1 < mddev->events)
+                        /* just a hot-add of a new device, leave raid_disk at -1 */
+                        return 0;
+        }
         if (mddev->level != LEVEL_MULTIPATH) {
                 int role;
                 rdev->desc_nr = le32_to_cpu(sb->dev_number);
@@ -1174,7 +1182,11 @@ static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
                         set_bit(Faulty, &rdev->flags);
                         break;
                 default:
-                        set_bit(In_sync, &rdev->flags);
+                        if ((le32_to_cpu(sb->feature_map) &
+                             MD_FEATURE_RECOVERY_OFFSET))
+                                rdev->recovery_offset = le64_to_cpu(sb->recovery_offset);
+                        else
+                                set_bit(In_sync, &rdev->flags);
                         rdev->raid_disk = role;
                         break;
                 }
@@ -1198,6 +1210,7 @@ static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
 
         sb->feature_map = 0;
         sb->pad0 = 0;
+        sb->recovery_offset = cpu_to_le64(0);
         memset(sb->pad1, 0, sizeof(sb->pad1));
         memset(sb->pad2, 0, sizeof(sb->pad2));
         memset(sb->pad3, 0, sizeof(sb->pad3));
@@ -1218,6 +1231,14 @@ static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
                 sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_offset);
                 sb->feature_map = cpu_to_le32(MD_FEATURE_BITMAP_OFFSET);
         }
+
+        if (rdev->raid_disk >= 0 &&
+            !test_bit(In_sync, &rdev->flags) &&
+            rdev->recovery_offset > 0) {
+                sb->feature_map |= cpu_to_le32(MD_FEATURE_RECOVERY_OFFSET);
+                sb->recovery_offset = cpu_to_le64(rdev->recovery_offset);
+        }
+
         if (mddev->reshape_position != MaxSector) {
                 sb->feature_map |= cpu_to_le32(MD_FEATURE_RESHAPE_ACTIVE);
                 sb->reshape_position = cpu_to_le64(mddev->reshape_position);
@@ -1242,11 +1263,12 @@ static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
                         sb->dev_roles[i] = cpu_to_le16(0xfffe);
                 else if (test_bit(In_sync, &rdev2->flags))
                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
+                else if (rdev2->raid_disk >= 0 && rdev2->recovery_offset > 0)
+                        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);
 }
 
@@ -1507,7 +1529,7 @@ static void print_rdev(mdk_rdev_t *rdev)
                 printk(KERN_INFO "md: no rdev superblock!\n");
 }
 
-void md_print_devices(void)
+static void md_print_devices(void)
 {
         struct list_head *tmp, *tmp2;
         mdk_rdev_t *rdev;
@@ -1536,15 +1558,30 @@ void md_print_devices(void)
 }
 
 
-static void sync_sbs(mddev_t * mddev)
+static void sync_sbs(mddev_t * mddev, int nospares)
 {
+        /* Update each superblock (in-memory image), but
+         * if we are allowed to, skip spares which already
+         * have the right event counter, or have one earlier
+         * (which would mean they aren't being marked as dirty
+         * with the rest of the array)
+         */
         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;
+                if (rdev->sb_events == mddev->events ||
+                    (nospares &&
+                     rdev->raid_disk < 0 &&
+                     (rdev->sb_events&1)==0 &&
+                     rdev->sb_events+1 == mddev->events)) {
+                        /* Don't update this superblock */
+                        rdev->sb_loaded = 2;
+                } else {
+                        super_types[mddev->major_version].
+                                sync_super(mddev, rdev);
+                        rdev->sb_loaded = 1;
+                }
         }
 }
 
@@ -1554,12 +1591,42 @@ void md_update_sb(mddev_t * mddev)
         struct list_head *tmp;
         mdk_rdev_t *rdev;
         int sync_req;
+        int nospares = 0;
 
 repeat:
         spin_lock_irq(&mddev->write_lock);
         sync_req = mddev->in_sync;
         mddev->utime = get_seconds();
-        mddev->events ++;
+        if (mddev->sb_dirty == 3)
+                /* just a clean<-> dirty transition, possibly leave spares alone,
+                 * though if events isn't the right even/odd, we will have to do
+                 * spares after all
+                 */
+                nospares = 1;
+
+        /* If this is just a dirty<->clean transition, and the array is clean
+         * and 'events' is odd, we can roll back to the previous clean state */
+        if (mddev->sb_dirty == 3
+            && (mddev->in_sync && mddev->recovery_cp == MaxSector)
+            && (mddev->events & 1))
+                mddev->events--;
+        else {
+                /* otherwise we have to go forward and ... */
+                mddev->events ++;
+                if (!mddev->in_sync || mddev->recovery_cp != MaxSector) { /* not clean */
+                        /* .. if the array isn't clean, insist on an odd 'events' */
+                        if ((mddev->events&1)==0) {
+                                mddev->events++;
+                                nospares = 0;
+                        }
+                } else {
+                        /* otherwise insist on an even 'events' (for clean states) */
+                        if ((mddev->events&1)) {
+                                mddev->events++;
+                                nospares = 0;
+                        }
+                }
+        }
 
         if (!mddev->events) {
                 /*
@@ -1571,7 +1638,7 @@ repeat:
                 mddev->events --;
         }
         mddev->sb_dirty = 2;
-        sync_sbs(mddev);
+        sync_sbs(mddev, nospares);
 
         /*
          * do not write anything to disk if using
@@ -1593,6 +1660,8 @@ repeat:
         ITERATE_RDEV(mddev,rdev,tmp) {
                 char b[BDEVNAME_SIZE];
                 dprintk(KERN_INFO "md: ");
+                if (rdev->sb_loaded != 1)
+                        continue; /* no noise on spare devices */
                 if (test_bit(Faulty, &rdev->flags))
                         dprintk("(skipping faulty ");
 
@@ -1604,6 +1673,7 @@ repeat:
                         dprintk(KERN_INFO "(write) %s's sb offset: %llu\n",
                                 bdevname(rdev->bdev,b),
                                 (unsigned long long)rdev->sb_offset);
+                        rdev->sb_events = mddev->events;
 
                 } else
                         dprintk(")\n");
@@ -1667,6 +1737,10 @@ state_show(mdk_rdev_t *rdev, char *page)
                 len += sprintf(page+len, "%sin_sync",sep);
                 sep = ",";
         }
+        if (test_bit(WriteMostly, &rdev->flags)) {
+                len += sprintf(page+len, "%swrite_mostly",sep);
+                sep = ",";
+        }
         if (!test_bit(Faulty, &rdev->flags) &&
             !test_bit(In_sync, &rdev->flags)) {
                 len += sprintf(page+len, "%sspare", sep);
@@ -1675,8 +1749,40 @@ state_show(mdk_rdev_t *rdev, char *page)
         return len+sprintf(page+len, "\n");
 }
 
+static ssize_t
+state_store(mdk_rdev_t *rdev, const char *buf, size_t len)
+{
+        /* can write
+         *  faulty  - simulates and error
+         *  remove  - disconnects the device
+         *  writemostly - sets write_mostly
+         *  -writemostly - clears write_mostly
+         */
+        int err = -EINVAL;
+        if (cmd_match(buf, "faulty") && rdev->mddev->pers) {
+                md_error(rdev->mddev, rdev);
+                err = 0;
+        } else if (cmd_match(buf, "remove")) {
+                if (rdev->raid_disk >= 0)
+                        err = -EBUSY;
+                else {
+                        mddev_t *mddev = rdev->mddev;
+                        kick_rdev_from_array(rdev);
+                        md_update_sb(mddev);
+                        md_new_event(mddev);
+                        err = 0;
+                }
+        } else if (cmd_match(buf, "writemostly")) {
+                set_bit(WriteMostly, &rdev->flags);
+                err = 0;
+        } else if (cmd_match(buf, "-writemostly")) {
+                clear_bit(WriteMostly, &rdev->flags);
+                err = 0;
+        }
+        return err ? err : len;
+}
 static struct rdev_sysfs_entry
-rdev_state = __ATTR_RO(state);
+rdev_state = __ATTR(state, 0644, state_show, state_store);
 
 static ssize_t
 super_show(mdk_rdev_t *rdev, char *page)
@@ -1873,6 +1979,7 @@ static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_mi
         rdev->desc_nr = -1;
         rdev->flags = 0;
         rdev->data_offset = 0;
+        rdev->sb_events = 0;
         atomic_set(&rdev->nr_pending, 0);
         atomic_set(&rdev->read_errors, 0);
         atomic_set(&rdev->corrected_errors, 0);
@@ -1978,6 +2085,54 @@ static void analyze_sbs(mddev_t * mddev)
 }
 
 static ssize_t
+safe_delay_show(mddev_t *mddev, char *page)
+{
+        int msec = (mddev->safemode_delay*1000)/HZ;
+        return sprintf(page, "%d.%03d\n", msec/1000, msec%1000);
+}
+static ssize_t
+safe_delay_store(mddev_t *mddev, const char *cbuf, size_t len)
+{
+        int scale=1;
+        int dot=0;
+        int i;
+        unsigned long msec;
+        char buf[30];
+        char *e;
+        /* remove a period, and count digits after it */
+        if (len >= sizeof(buf))
+                return -EINVAL;
+        strlcpy(buf, cbuf, len);
+        buf[len] = 0;
+        for (i=0; i<len; i++) {
+                if (dot) {
+                        if (isdigit(buf[i])) {
+                                buf[i-1] = buf[i];
+                                scale *= 10;
+                        }
+                        buf[i] = 0;
+                } else if (buf[i] == '.') {
+                        dot=1;
+                        buf[i] = 0;
+                }
+        }
+        msec = simple_strtoul(buf, &e, 10);
+        if (e == buf || (*e && *e != '\n'))
+                return -EINVAL;
+        msec = (msec * 1000) / scale;
+        if (msec == 0)
+                mddev->safemode_delay = 0;
+        else {
+                mddev->safemode_delay = (msec*HZ)/1000;
+                if (mddev->safemode_delay == 0)
+                        mddev->safemode_delay = 1;
+        }
+        return len;
+}
+static struct md_sysfs_entry md_safe_delay =
+__ATTR(safe_mode_delay, 0644,safe_delay_show, safe_delay_store);
+
+static ssize_t
 level_show(mddev_t *mddev, char *page)
 {
         struct mdk_personality *p = mddev->pers;
@@ -2012,6 +2167,32 @@ level_store(mddev_t *mddev, const char *buf, size_t len)
 static struct md_sysfs_entry md_level =
 __ATTR(level, 0644, level_show, level_store);
 
+
+static ssize_t
+layout_show(mddev_t *mddev, char *page)
+{
+        /* just a number, not meaningful for all levels */
+        return sprintf(page, "%d\n", mddev->layout);
+}
+
+static ssize_t
+layout_store(mddev_t *mddev, const char *buf, size_t len)
+{
+        char *e;
+        unsigned long n = simple_strtoul(buf, &e, 10);
+        if (mddev->pers)
+                return -EBUSY;
+
+        if (!*buf || (*e && *e != '\n'))
+                return -EINVAL;
+
+        mddev->layout = n;
+        return len;
+}
+static struct md_sysfs_entry md_layout =
+__ATTR(layout, 0655, layout_show, layout_store);
+
+
 static ssize_t
 raid_disks_show(mddev_t *mddev, char *page)
 {
@@ -2067,6 +2248,200 @@ static struct md_sysfs_entry md_chunk_size =
 __ATTR(chunk_size, 0644, chunk_size_show, chunk_size_store);
 
 static ssize_t
+resync_start_show(mddev_t *mddev, char *page)
+{
+        return sprintf(page, "%llu\n", (unsigned long long)mddev->recovery_cp);
+}
+
+static ssize_t
+resync_start_store(mddev_t *mddev, const char *buf, size_t len)
+{
+        /* can only set chunk_size if array is not yet active */
+        char *e;
+        unsigned long long n = simple_strtoull(buf, &e, 10);
+
+        if (mddev->pers)
+                return -EBUSY;
+        if (!*buf || (*e && *e != '\n'))
+                return -EINVAL;
+
+        mddev->recovery_cp = n;
+        return len;
+}
+static struct md_sysfs_entry md_resync_start =
+__ATTR(resync_start, 0644, resync_start_show, resync_start_store);
+
+/*
+ * The array state can be:
+ *
+ * clear
+ *     No devices, no size, no level
+ *     Equivalent to STOP_ARRAY ioctl
+ * inactive
+ *     May have some settings, but array is not active
+ *        all IO results in error
+ *     When written, doesn't tear down array, but just stops it
+ * suspended (not supported yet)
+ *     All IO requests will block. The array can be reconfigured.
+ *     Writing this, if accepted, will block until array is quiessent
+ * readonly
+ *     no resync can happen.  no superblocks get written.
+ *     write requests fail
+ * read-auto
+ *     like readonly, but behaves like 'clean' on a write request.
+ *
+ * clean - no pending writes, but otherwise active.
+ *     When written to inactive array, starts without resync
+ *     If a write request arrives then
+ *       if metadata is known, mark 'dirty' and switch to 'active'.
+ *       if not known, block and switch to write-pending
+ *     If written to an active array that has pending writes, then fails.
+ * active
+ *     fully active: IO and resync can be happening.
+ *     When written to inactive array, starts with resync
+ *
+ * write-pending
+ *     clean, but writes are blocked waiting for 'active' to be written.
+ *
+ * active-idle
+ *     like active, but no writes have been seen for a while (100msec).
+ *
+ */
+enum array_state { clear, inactive, suspended, readonly, read_auto, clean, active,
+                   write_pending, active_idle, bad_word};
+static char *array_states[] = {
+        "clear", "inactive", "suspended", "readonly", "read-auto", "clean", "active",
+        "write-pending", "active-idle", NULL };
+
+static int match_word(const char *word, char **list)
+{
+        int n;
+        for (n=0; list[n]; n++)
+                if (cmd_match(word, list[n]))
+                        break;
+        return n;
+}
+
+static ssize_t
+array_state_show(mddev_t *mddev, char *page)
+{
+        enum array_state st = inactive;
+
+        if (mddev->pers)
+                switch(mddev->ro) {
+                case 1:
+                        st = readonly;
+                        break;
+                case 2:
+                        st = read_auto;
+                        break;
+                case 0:
+                        if (mddev->in_sync)
+                                st = clean;
+                        else if (mddev->safemode)
+                                st = active_idle;
+                        else
+                                st = active;
+                }
+        else {
+                if (list_empty(&mddev->disks) &&
+                    mddev->raid_disks == 0 &&
+                    mddev->size == 0)
+                        st = clear;
+                else
+                        st = inactive;
+        }
+        return sprintf(page, "%s\n", array_states[st]);
+}
+
+static int do_md_stop(mddev_t * mddev, int ro);
+static int do_md_run(mddev_t * mddev);
+static int restart_array(mddev_t *mddev);
+
+static ssize_t
+array_state_store(mddev_t *mddev, const char *buf, size_t len)
+{
+        int err = -EINVAL;
+        enum array_state st = match_word(buf, array_states);
+        switch(st) {
+        case bad_word:
+                break;
+        case clear:
+                /* stopping an active array */
+                if (mddev->pers) {
+                        if (atomic_read(&mddev->active) > 1)
+                                return -EBUSY;
+                        err = do_md_stop(mddev, 0);
+                }
+                break;
+        case inactive:
+                /* stopping an active array */
+                if (mddev->pers) {
+                        if (atomic_read(&mddev->active) > 1)
+                                return -EBUSY;
+                        err = do_md_stop(mddev, 2);
+                }
+                break;
+        case suspended:
+                break; /* not supported yet */
+        case readonly:
+                if (mddev->pers)
+                        err = do_md_stop(mddev, 1);
+                else {
+                        mddev->ro = 1;
+                        err = do_md_run(mddev);
+                }
+                break;
+        case read_auto:
+                /* stopping an active array */
+                if (mddev->pers) {
+                        err = do_md_stop(mddev, 1);
+                        if (err == 0)
+                                mddev->ro = 2; /* FIXME mark devices writable */
+                } else {
+                        mddev->ro = 2;
+                        err = do_md_run(mddev);
+                }
+                break;
+        case clean:
+                if (mddev->pers) {
+                        restart_array(mddev);
+                        spin_lock_irq(&mddev->write_lock);
+                        if (atomic_read(&mddev->writes_pending) == 0) {
+                                mddev->in_sync = 1;
+                                mddev->sb_dirty = 1;
+                        }
+                        spin_unlock_irq(&mddev->write_lock);
+                } else {
+                        mddev->ro = 0;
+                        mddev->recovery_cp = MaxSector;
+                        err = do_md_run(mddev);
+                }
+                break;
+        case active:
+                if (mddev->pers) {
+                        restart_array(mddev);
+                        mddev->sb_dirty = 0;
+                        wake_up(&mddev->sb_wait);
+                        err = 0;
+                } else {
+                        mddev->ro = 0;
+                        err = do_md_run(mddev);
+                }
+                break;
+        case write_pending:
+        case active_idle:
+                /* these cannot be set */
+                break;
+        }
+        if (err)
+                return err;
+        else
+                return len;
+}
+static struct md_sysfs_entry md_array_state = __ATTR(array_state, 0644, array_state_show, array_state_store);
+
+static ssize_t
 null_show(mddev_t *mddev, char *page)
 {
         return -EINVAL;
@@ -2428,11 +2803,15 @@ __ATTR(suspend_hi, S_IRUGO|S_IWUSR, suspend_hi_show, suspend_hi_store);
 
 static struct attribute *md_default_attrs[] = {
         &md_level.attr,
+        &md_layout.attr,
         &md_raid_disks.attr,
         &md_chunk_size.attr,
         &md_size.attr,
+        &md_resync_start.attr,
         &md_metadata.attr,
         &md_new_device.attr,
+        &md_safe_delay.attr,
+        &md_array_state.attr,
         NULL,
 };
 
@@ -2553,8 +2932,6 @@ static struct kobject *md_probe(dev_t dev, int *part, void *data)
         return NULL;
 }
 
-void md_wakeup_thread(mdk_thread_t *thread);
-
 static void md_safemode_timeout(unsigned long data)
 {
         mddev_t *mddev = (mddev_t *) data;
@@ -2708,7 +3085,7 @@ static int do_md_run(mddev_t * mddev)
         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->safemode_delay = (200 * HZ)/1000 +1; /* 200 msec delay */
         mddev->in_sync = 1;
 
         ITERATE_RDEV(mddev,rdev,tmp)
@@ -2736,6 +3113,36 @@ static int do_md_run(mddev_t * mddev)
         mddev->queue->queuedata = mddev;
         mddev->queue->make_request_fn = mddev->pers->make_request;
 
+        /* If there is a partially-recovered drive we need to
+         * start recovery here.  If we leave it to md_check_recovery,
+         * it will remove the drives and not do the right thing
+         */
+        if (mddev->degraded) {
+                struct list_head *rtmp;
+                int spares = 0;
+                ITERATE_RDEV(mddev,rdev,rtmp)
+                        if (rdev->raid_disk >= 0 &&
+                            !test_bit(In_sync, &rdev->flags) &&
+                            !test_bit(Faulty, &rdev->flags))
+                                /* complete an interrupted recovery */
+                                spares++;
+                if (spares && mddev->pers->sync_request) {
+                        mddev->recovery = 0;
+                        set_bit(MD_RECOVERY_RUNNING, &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);
+                }
+        }
+
         mddev->changed = 1;
         md_new_event(mddev);
         return 0;
@@ -2769,18 +3176,47 @@ static int restart_array(mddev_t *mddev)
                  */
                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
                 md_wakeup_thread(mddev->thread);
+                md_wakeup_thread(mddev->sync_thread);
                 err = 0;
-        } else {
-                printk(KERN_ERR "md: %s has no personality assigned.\n",
-                        mdname(mddev));
+        } else
                 err = -EINVAL;
-        }
 
 out:
         return err;
 }
 
-static int do_md_stop(mddev_t * mddev, int ro)
+/* similar to deny_write_access, but accounts for our holding a reference
+ * to the file ourselves */
+static int deny_bitmap_write_access(struct file * file)
+{
+        struct inode *inode = file->f_mapping->host;
+
+        spin_lock(&inode->i_lock);
+        if (atomic_read(&inode->i_writecount) > 1) {
+                spin_unlock(&inode->i_lock);
+                return -ETXTBSY;
+        }
+        atomic_set(&inode->i_writecount, -1);
+        spin_unlock(&inode->i_lock);
+
+        return 0;
+}
+
+static void restore_bitmap_write_access(struct file *file)
+{
+        struct inode *inode = file->f_mapping->host;
+
+        spin_lock(&inode->i_lock);
+        atomic_set(&inode->i_writecount, 1);
+        spin_unlock(&inode->i_lock);
+}
+
+/* mode:
+ *   0 - completely stop and dis-assemble array
+ *   1 - switch to readonly
+ *   2 - stop but do not disassemble array
+ */
+static int do_md_stop(mddev_t * mddev, int mode)
 {
         int err = 0;
         struct gendisk *disk = mddev->gendisk;
@@ -2792,6 +3228,7 @@ static int do_md_stop(mddev_t * mddev, int ro)
                 }
 
                 if (mddev->sync_thread) {
+                        set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
                         md_unregister_thread(mddev->sync_thread);
                         mddev->sync_thread = NULL;
@@ -2801,12 +3238,15 @@ static int do_md_stop(mddev_t * mddev, int ro)
 
                 invalidate_partition(disk, 0);
 
-                if (ro) {
+                switch(mode) {
+                case 1: /* readonly */
                         err  = -ENXIO;
                         if (mddev->ro==1)
                                 goto out;
                         mddev->ro = 1;
-                } else {
+                        break;
+                case 0: /* disassemble */
+                case 2: /* stop */
                         bitmap_flush(mddev);
                         md_super_wait(mddev);
                         if (mddev->ro)
@@ -2821,19 +3261,20 @@ static int do_md_stop(mddev_t * mddev, int ro)
                         if (mddev->ro)
                                 mddev->ro = 0;
                 }
-                if (!mddev->in_sync) {
+                if (!mddev->in_sync || mddev->sb_dirty) {
                         /* mark array as shutdown cleanly */
                         mddev->in_sync = 1;
                         md_update_sb(mddev);
                 }
-                if (ro)
+                if (mode == 1)
                         set_disk_ro(disk, 1);
+                clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
         }
 
         /*
          * Free resources if final stop
          */
-        if (!ro) {
+        if (mode == 0) {
                 mdk_rdev_t *rdev;
                 struct list_head *tmp;
                 struct gendisk *disk;
@@ -2841,7 +3282,7 @@ static int do_md_stop(mddev_t * mddev, int ro)
 
                 bitmap_destroy(mddev);
                 if (mddev->bitmap_file) {
-                        atomic_set(&mddev->bitmap_file->f_dentry->d_inode->i_writecount, 1);
+                        restore_bitmap_write_access(mddev->bitmap_file);
                         fput(mddev->bitmap_file);
                         mddev->bitmap_file = NULL;
                 }
@@ -2857,11 +3298,15 @@ static int do_md_stop(mddev_t * mddev, int ro)
                 export_array(mddev);
 
                 mddev->array_size = 0;
+                mddev->size = 0;
+                mddev->raid_disks = 0;
+                mddev->recovery_cp = 0;
+
                 disk = mddev->gendisk;
                 if (disk)
                         set_capacity(disk, 0);
                 mddev->changed = 1;
-        } else
+        } else if (mddev->pers)
                 printk(KERN_INFO "md: %s switched to read-only mode.\n",
                         mdname(mddev));
         err = 0;
@@ -3264,6 +3709,17 @@ static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
 
                 rdev->raid_disk = -1;
                 err = bind_rdev_to_array(rdev, mddev);
+                if (!err && !mddev->pers->hot_remove_disk) {
+                        /* If there is hot_add_disk but no hot_remove_disk
+                         * then added disks for geometry changes,
+                         * and should be added immediately.
+                         */
+                        super_types[mddev->major_version].
+                                validate_super(mddev, rdev);
+                        err = mddev->pers->hot_add_disk(mddev, rdev);
+                        if (err)
+                                unbind_rdev_from_array(rdev);
+                }
                 if (err)
                         export_rdev(rdev);
 
@@ -3434,23 +3890,6 @@ abort_export:
         return err;
 }
 
-/* similar to deny_write_access, but accounts for our holding a reference
- * to the file ourselves */
-static int deny_bitmap_write_access(struct file * file)
-{
-        struct inode *inode = file->f_mapping->host;
-
-        spin_lock(&inode->i_lock);
-        if (atomic_read(&inode->i_writecount) > 1) {
-                spin_unlock(&inode->i_lock);
-                return -ETXTBSY;
-        }
-        atomic_set(&inode->i_writecount, -1);
-        spin_unlock(&inode->i_lock);
-
-        return 0;
-}
-
 static int set_bitmap_file(mddev_t *mddev, int fd)
 {
         int err;
@@ -3491,12 +3930,17 @@ static int set_bitmap_file(mddev_t *mddev, int fd)
                 mddev->pers->quiesce(mddev, 1);
                 if (fd >= 0)
                         err = bitmap_create(mddev);
-                if (fd < 0 || err)
+                if (fd < 0 || err) {
                         bitmap_destroy(mddev);
+                        fd = -1; /* make sure to put the file */
+                }
                 mddev->pers->quiesce(mddev, 0);
-        } else if (fd < 0) {
-                if (mddev->bitmap_file)
+        }
+        if (fd < 0) {
+                if (mddev->bitmap_file) {
+                        restore_bitmap_write_access(mddev->bitmap_file);
                         fput(mddev->bitmap_file);
+                }
                 mddev->bitmap_file = NULL;
         }
 
@@ -3977,11 +4421,6 @@ static int md_ioctl(struct inode *inode, struct file *file,
                         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;
         }
@@ -4586,7 +5025,7 @@ void md_write_start(mddev_t *mddev, struct bio *bi)
                 spin_lock_irq(&mddev->write_lock);
                 if (mddev->in_sync) {
                         mddev->in_sync = 0;
-                        mddev->sb_dirty = 1;
+                        mddev->sb_dirty = 3;
                         md_wakeup_thread(mddev->thread);
                 }
                 spin_unlock_irq(&mddev->write_lock);
@@ -4599,7 +5038,7 @@ 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
+                else if (mddev->safemode_delay)
                         mod_timer(&mddev->safemode_timer, jiffies + mddev->safemode_delay);
         }
 }
@@ -4620,10 +5059,14 @@ void md_do_sync(mddev_t *mddev)
         struct list_head *tmp;
         sector_t last_check;
         int skipped = 0;
+        struct list_head *rtmp;
+        mdk_rdev_t *rdev;
 
         /* just incase thread restarts... */
         if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
                 return;
+        if (mddev->ro) /* never try to sync a read-only array */
+                return;
 
         /* we overload curr_resync somewhat here.
          * 0 == not engaged in resync at all
@@ -4682,17 +5125,30 @@ void md_do_sync(mddev_t *mddev)
                 }
         } while (mddev->curr_resync < 2);
 
+        j = 0;
         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
                 /* resync follows the size requested by the personality,
                  * which defaults to physical size, but can be virtual size
                  */
                 max_sectors = mddev->resync_max_sectors;
                 mddev->resync_mismatches = 0;
+                /* we don't use the checkpoint if there's a bitmap */
+                if (!mddev->bitmap &&
+                    !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
+                        j = mddev->recovery_cp;
         } else if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
                 max_sectors = mddev->size << 1;
-        else
+        else {
                 /* recovery follows the physical size of devices */
                 max_sectors = mddev->size << 1;
+                j = MaxSector;
+                ITERATE_RDEV(mddev,rdev,rtmp)
+                        if (rdev->raid_disk >= 0 &&
+                            !test_bit(Faulty, &rdev->flags) &&
+                            !test_bit(In_sync, &rdev->flags) &&
+                            rdev->recovery_offset < j)
+                                j = rdev->recovery_offset;
+        }
 
         printk(KERN_INFO "md: syncing RAID array %s\n", mdname(mddev));
         printk(KERN_INFO "md: minimum _guaranteed_ reconstruction speed:"
@@ -4702,12 +5158,7 @@ void md_do_sync(mddev_t *mddev)
                speed_max(mddev));
 
         is_mddev_idle(mddev); /* this also initializes IO event counters */
-        /* we don't use the checkpoint if there's a bitmap */
-        if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && !mddev->bitmap
-            && ! test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
-                j = mddev->recovery_cp;
-        else
-                j = 0;
+
         io_sectors = 0;
         for (m = 0; m < SYNC_MARKS; m++) {
                 mark[m] = jiffies;
@@ -4828,15 +5279,28 @@ void md_do_sync(mddev_t *mddev)
         if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
             test_bit(MD_RECOVERY_SYNC, &mddev->recovery) &&
             !test_bit(MD_RECOVERY_CHECK, &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;
+            mddev->curr_resync > 2) {
+                if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
+                        if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
+                                if (mddev->curr_resync >= mddev->recovery_cp) {
+                                        printk(KERN_INFO
+                                               "md: checkpointing recovery of %s.\n",
+                                               mdname(mddev));
+                                        mddev->recovery_cp = mddev->curr_resync;
+                                }
+                        } else
+                                mddev->recovery_cp = MaxSector;
+                } else {
+                        if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery))
+                                mddev->curr_resync = MaxSector;
+                        ITERATE_RDEV(mddev,rdev,rtmp)
+                                if (rdev->raid_disk >= 0 &&
+                                    !test_bit(Faulty, &rdev->flags) &&
+                                    !test_bit(In_sync, &rdev->flags) &&
+                                    rdev->recovery_offset < mddev->curr_resync)
+                                        rdev->recovery_offset = mddev->curr_resync;
+                        mddev->sb_dirty = 1;
+                }
         }
 
  skip:
@@ -4908,7 +5372,7 @@ void md_check_recovery(mddev_t *mddev)
                 if (mddev->safemode && !atomic_read(&mddev->writes_pending) &&
                     !mddev->in_sync && mddev->recovery_cp == MaxSector) {
                         mddev->in_sync = 1;
-                        mddev->sb_dirty = 1;
+                        mddev->sb_dirty = 3;
                 }
                 if (mddev->safemode == 1)
                         mddev->safemode = 0;
@@ -4957,6 +5421,8 @@ void md_check_recovery(mddev_t *mddev)
                 clear_bit(MD_RECOVERY_INTR, &mddev->recovery);
                 clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
 
+                if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
+                        goto unlock;
                 /* no recovery is running.
                  * remove any failed drives, then
                  * add spares if possible.
@@ -4979,6 +5445,7 @@ void md_check_recovery(mddev_t *mddev)
                         ITERATE_RDEV(mddev,rdev,rtmp)
                                 if (rdev->raid_disk < 0
                                     && !test_bit(Faulty, &rdev->flags)) {
+                                        rdev->recovery_offset = 0;
                                         if (mddev->pers->hot_add_disk(mddev,rdev)) {
                                                 char nm[20];
                                                 sprintf(nm, "rd%d", rdev->raid_disk);
@@ -5216,7 +5683,6 @@ EXPORT_SYMBOL(md_write_end);
 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");
 MODULE_ALIAS("md");