1 files changed, 33 insertions, 16 deletions

diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 763a315712cc..49862993f31e 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -1142,31 +1142,48 @@ static int blkif_open(struct block_device *bdev, fmode_t mode)
         if (!err)
                 ++info->users;
 
-        unlock_kernel();
 out:
+        unlock_kernel();
         return err;
 }
 
 static int blkif_release(struct gendisk *disk, fmode_t mode)
 {
         struct blkfront_info *info = disk->private_data;
+        struct block_device *bdev;
+        struct xenbus_device *xbdev;
+
         lock_kernel();
-        info->users--;
-        if (info->users == 0) {
-                /* Check whether we have been instructed to close.  We will
-                   have ignored this request initially, as the device was
-                   still mounted. */
-                struct xenbus_device *dev = info->xbdev;
-
-                if (!dev) {
-                        xlvbd_release_gendisk(info);
-                        kfree(info);
-                } else if (xenbus_read_driver_state(dev->otherend)
-                           == XenbusStateClosing && info->is_ready) {
-                        xlvbd_release_gendisk(info);
-                        xenbus_frontend_closed(dev);
-                }
+        if (--info->users)
+                goto out;
+
+        bdev = bdget_disk(disk, 0);
+        bdput(bdev);
+
+        /*
+         * Check if we have been instructed to close. We will have
+         * deferred this request, because the bdev was still open.
+         */
+
+        mutex_lock(&info->mutex);
+        xbdev = info->xbdev;
+
+        if (xbdev && xbdev->state == XenbusStateClosing) {
+                /* pending switch to state closed */
+                xlvbd_release_gendisk(info);
+                xenbus_frontend_closed(info->xbdev);
+        }
+
+        mutex_unlock(&info->mutex);
+
+        if (!xbdev) {
+                /* sudden device removal */
+                xlvbd_release_gendisk(info);
+                disk->private_data = NULL;
+                kfree(info);
         }
+
+out:
         unlock_kernel();
         return 0;
 }