md: allow extended partitions on md devices.

The new extended partition support provides a much nicer was
to have partitions on md devices that the 'mdp' alternate major.
We cannot really get rid of 'mdp' at this time, but we can
enable extended partitions as that will probably make life
easier for sysadmins.

Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 8b303477c77..d255997bf63 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -3463,6 +3463,11 @@ static struct kobject *md_probe(dev_t dev, int *part, void *data)
         disk->fops = &md_fops;
         disk->private_data = mddev;
         disk->queue = mddev->queue;
+        /* Allow extended partitions.  This makes the
+         * 'mdp' device redundant, but we can really
+         * remove it now.
+         */
+        disk->flags |= GENHD_FL_EXT_DEVT;
         add_disk(disk);
         mddev->gendisk = disk;
         error = kobject_init_and_add(&mddev->kobj, &md_ktype,