It works nicely with the QMP commands, but it adds useless complication
with HMP. In particular, see the following:
(qemu) nbd_server_add -w scsi0-hd0
(qemu) nbd_server_start -a localhost:10809
NBD server already exporting device scsi0-hd0
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
NBDExport *exp;
NBDCloseNotifier *n;
+ if (server_fd == -1) {
+ error_setg(errp, "NBD server not running");
+ return;
+ }
+
if (nbd_export_find(device)) {
error_setg(errp, "NBD server already exporting device '%s'", device);
return;