md: destroy partitions and notify udev when md array is stopped.

md arrays are not currently destroyed when they are stopped - they
remain in /sys/block.  Last time I tried this I tripped over locking
too much.

A consequence of this is that udev doesn't remove anything from /dev.
This is rather ugly.

As an interim measure until proper device removal can be achieved,
make sure all partitions are removed using the BLKRRPART ioctl, and
send a KOBJ_CHANGE when an md array is stopped.

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

1 files changed, 7 insertions, 0 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index b4162f6f1b79..9abf6ed16535 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -3884,6 +3884,7 @@ static int do_md_stop(mddev_t * mddev, int mode, int is_open)
         if (mode == 0) {
                 mdk_rdev_t *rdev;
                 struct list_head *tmp;
+                struct block_device *bdev;
 
                 printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
 
@@ -3940,6 +3941,12 @@ static int do_md_stop(mddev_t * mddev, int mode, int is_open)
                 mddev->degraded = 0;
                 mddev->barriers_work = 0;
                 mddev->safemode = 0;
+                bdev = bdget_disk(mddev->gendisk, 0);
+                if (bdev) {
+                        blkdev_ioctl(bdev, 0, BLKRRPART, 0);
+                        bdput(bdev);
+                }
+                kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
 
         } else if (mddev->pers)
                 printk(KERN_INFO "md: %s switched to read-only mode.\n",