summaryrefslogtreecommitdiffstats
path: root/drivers/block
diff options
context:
space:
mode:
authorAlexander Graf <agraf@suse.de>2013-01-02 15:37:17 +1030
committerRusty Russell <rusty@rustcorp.com.au>2013-01-02 15:37:58 +1030
commitf4953fe6c4aeada2d5cafd78aa97587a46d2d8f9 (patch)
tree25dea7884cb125d2c0f76a38938eb624c94ec228 /drivers/block
parenta7f2a366f62319dfebf8d4dfe8b211f631c78457 (diff)
downloadlinux-f4953fe6c4aeada2d5cafd78aa97587a46d2d8f9.tar.gz
linux-f4953fe6c4aeada2d5cafd78aa97587a46d2d8f9.tar.bz2
linux-f4953fe6c4aeada2d5cafd78aa97587a46d2d8f9.zip
virtio-blk: Don't free ida when disk is in use
When a file system is mounted on a virtio-blk disk, we then remove it and then reattach it, the reattached disk gets the same disk name and ids as the hot removed one. This leads to very nasty effects - mostly rendering the newly attached device completely unusable. Trying what happens when I do the same thing with a USB device, I saw that the sd node simply doesn't get free'd when a device gets forcefully removed. Imitate the same behavior for vd devices. This way broken vd devices simply are never free'd and newly attached ones keep working just fine. Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: stable@kernel.org
Diffstat (limited to 'drivers/block')
-rw-r--r--drivers/block/virtio_blk.c7
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 0bdde8fba397..07a18e238483 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -889,6 +889,7 @@ static void __devexit virtblk_remove(struct virtio_device *vdev)
{
struct virtio_blk *vblk = vdev->priv;
int index = vblk->index;
+ int refc;
/* Prevent config work handler from accessing the device. */
mutex_lock(&vblk->config_lock);
@@ -903,11 +904,15 @@ static void __devexit virtblk_remove(struct virtio_device *vdev)
flush_work(&vblk->config_work);
+ refc = atomic_read(&disk_to_dev(vblk->disk)->kobj.kref.refcount);
put_disk(vblk->disk);
mempool_destroy(vblk->pool);
vdev->config->del_vqs(vdev);
kfree(vblk);
- ida_simple_remove(&vd_index_ida, index);
+
+ /* Only free device id if we don't have any users */
+ if (refc == 1)
+ ida_simple_remove(&vd_index_ida, index);
}
#ifdef CONFIG_PM