md: Skip cluster setup for dm-raid

[pandora-kernel.git] / drivers / md / bitmap.c

diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index 2bc56e2..c90118e 100644 (file)
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -177,11 +177,16 @@ static struct md_rdev *next_active_rdev(struct md_rdev *rdev, struct mddev *mdde
         * nr_pending is 0 and In_sync is clear, the entries we return will
         * still be in the same position on the list when we re-enter
         * list_for_each_entry_continue_rcu.
+        *
+        * Note that if entered with 'rdev == NULL' to start at the
+        * beginning, we temporarily assign 'rdev' to an address which
+        * isn't really an rdev, but which can be used by
+        * list_for_each_entry_continue_rcu() to find the first entry.
         */
        rcu_read_lock();
        if (rdev == NULL)
                /* start at the beginning */
-               rdev = list_entry_rcu(&mddev->disks, struct md_rdev, same_set);
+               rdev = list_entry(&mddev->disks, struct md_rdev, same_set);
        else {
                /* release the previous rdev and start from there. */
                rdev_dec_pending(rdev, mddev);
@@ -489,7 +494,7 @@ static int bitmap_new_disk_sb(struct bitmap *bitmap)
        bitmap_super_t *sb;
        unsigned long chunksize, daemon_sleep, write_behind;
 
-       bitmap->storage.sb_page = alloc_page(GFP_KERNEL);
+       bitmap->storage.sb_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
        if (bitmap->storage.sb_page == NULL)
                return -ENOMEM;
        bitmap->storage.sb_page->index = 0;
@@ -536,6 +541,7 @@ static int bitmap_new_disk_sb(struct bitmap *bitmap)
        sb->state = cpu_to_le32(bitmap->flags);
        bitmap->events_cleared = bitmap->mddev->events;
        sb->events_cleared = cpu_to_le64(bitmap->mddev->events);
+       bitmap->mddev->bitmap_info.nodes = 0;
 
        kunmap_atomic(sb);
 
@@ -606,8 +612,16 @@ re_read:
        daemon_sleep = le32_to_cpu(sb->daemon_sleep) * HZ;
        write_behind = le32_to_cpu(sb->write_behind);
        sectors_reserved = le32_to_cpu(sb->sectors_reserved);
-       nodes = le32_to_cpu(sb->nodes);
-       strlcpy(bitmap->mddev->bitmap_info.cluster_name, sb->cluster_name, 64);
+       /* XXX: This is a hack to ensure that we don't use clustering
+        *  in case:
+        *      - dm-raid is in use and
+        *      - the nodes written in bitmap_sb is erroneous.
+        */
+       if (!bitmap->mddev->sync_super) {
+               nodes = le32_to_cpu(sb->nodes);
+               strlcpy(bitmap->mddev->bitmap_info.cluster_name,
+                               sb->cluster_name, 64);
+       }
 
        /* verify that the bitmap-specific fields are valid */
        if (sb->magic != cpu_to_le32(BITMAP_MAGIC))