nbd: use BlockDriverState refcnt
Previously, nbd calls drive_get_ref() on the drive of bs. A BDS doesn't
always have associated dinfo, which nbd doesn't care either. We already
have BDS ref count, so use it to make it safe for a BDS w/o blockdev.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
diff --git a/nbd.c b/nbd.c
index 0fd0583..f847940 100644
--- a/nbd.c
+++ b/nbd.c
@@ -882,6 +882,7 @@
exp->nbdflags = nbdflags;
exp->size = size == -1 ? bdrv_getlength(bs) : size;
exp->close = close;
+ bdrv_ref(bs);
return exp;
}
@@ -928,6 +929,10 @@
}
nbd_export_set_name(exp, NULL);
nbd_export_put(exp);
+ if (exp->bs) {
+ bdrv_unref(exp->bs);
+ exp->bs = NULL;
+ }
}
void nbd_export_get(NBDExport *exp)
