[Qemu-devel] Close the BlockDriverState when guest eject the media

[Weidong Huang]

Hi ALL:

There are two ways to eject the cdrom tray. One is by the eject's qmp 
commmand(eject_device).
The another one is by the guest(bdrv_eject). They have different results.

eject_device: close the BlockDriverState(bdrv_close(bs))
bdrv_eject: don't close the BlockDriverState,

This is ambiguous. So libvirt can't handle some situations.

libvirt send eject qmp command ---> qemu send eject request to guest --->
guest respond to qemu ---> qemu emit tray_open event to libvirt --->
libvirt will not send change qmp command if media source is null. So
the media is not be replace to the null.

So close the BlockDriverState in bdrv_eject. Thanks.

diff --git a/block.c b/block.c
index d3aebeb..0be69de 100644
--- a/block.c
+++ b/block.c
@@ -5276,6 +5276,10 @@ void bdrv_eject(BlockDriverState *bs, bool eject_flag)
         qapi_event_send_device_tray_moved(bdrv_get_device_name(bs),
                                           eject_flag, &error_abort);
     }
+
+    if (eject_flag) {
+        bdrv_close(bs);
+    }
 }