xen_disk: simplify blk_disconnect with refcnt

We call bdrv_attach_dev when initializing whether or not bs is created
locally, so call bdrv_detach_dev and let the refcnt handle the
lifecycle.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Fam Zheng 2013-08-23 09:14:49 +08:00 committed by Stefan Hajnoczi
parent 8442cfd034
commit c0777fe18b

View File

@ -824,6 +824,9 @@ static int blk_connect(struct XenDevice *xendev)
/* setup via qemu cmdline -> already setup for us */
xen_be_printf(&blkdev->xendev, 2, "get configured bdrv (cmdline setup)\n");
blkdev->bs = blkdev->dinfo->bdrv;
/* blkdev->bs is not create by us, we get a reference
* so we can bdrv_unref() unconditionally */
bdrv_ref(blkdev->bs);
}
bdrv_attach_dev_nofail(blkdev->bs, blkdev);
blkdev->file_size = bdrv_getlength(blkdev->bs);
@ -922,12 +925,8 @@ static void blk_disconnect(struct XenDevice *xendev)
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
if (blkdev->bs) {
if (!blkdev->dinfo) {
/* close/delete only if we created it ourself */
bdrv_close(blkdev->bs);
bdrv_detach_dev(blkdev->bs, blkdev);
bdrv_unref(blkdev->bs);
}
bdrv_detach_dev(blkdev->bs, blkdev);
bdrv_unref(blkdev->bs);
blkdev->bs = NULL;
}
xen_be_unbind_evtchn(&blkdev->xendev);