[PATCH 1/1] vhost-scsi: support VIRTIO_SCSI_F_HOTPLUG

[Dongli Zhang]

So far there isn't way to test host kernel vhost-scsi event queue path,
because VIRTIO_SCSI_F_HOTPLUG isn't supported by QEMU.

virtio-scsi.c and vhost-user-scsi.c already support VIRTIO_SCSI_F_HOTPLUG
as property "hotplug".

Add support to vhost-scsi.c to help evaluate and test event queue.

To test the feature:

1. Create vhost-scsi target with targetcli.

targetcli /backstores/fileio create name=storage file_or_dev=disk01.raw
targetcli /vhost create naa.1123451234512345
targetcli /vhost/naa.1123451234512345/tpg1/luns create 
/backstores/fileio/storage

2. Create QEMU instance with vhost-scsi.

-device vhost-scsi-pci,wwpn=naa.1123451234512345,hotplug=true

3. Once guest bootup, hotplug a new LUN from host.

targetcli /backstores/fileio create name=storage02 file_or_dev=disk02.raw
targetcli /vhost/naa.1123451234512345/tpg1/luns create 
/backstores/fileio/storage02

Signed-off-by: Dongli Zhang <dongli.zh...@oracle.com>
---
 hw/scsi/vhost-scsi.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/hw/scsi/vhost-scsi.c b/hw/scsi/vhost-scsi.c
index 8039d13fd9..d3a260f6a7 100644
--- a/hw/scsi/vhost-scsi.c
+++ b/hw/scsi/vhost-scsi.c
@@ -359,6 +359,9 @@ static const Property vhost_scsi_properties[] = {
     DEFINE_PROP_BIT64("t10_pi", VHostSCSICommon, host_features,
                                                  VIRTIO_SCSI_F_T10_PI,
                                                  false),
+    DEFINE_PROP_BIT64("hotplug", VHostSCSICommon, host_features,
+                                                  VIRTIO_SCSI_F_HOTPLUG,
+                                                  false),
     DEFINE_PROP_BOOL("migratable", VHostSCSICommon, migratable, false),
     DEFINE_PROP_BOOL("worker_per_virtqueue", VirtIOSCSICommon,
                      conf.worker_per_virtqueue, false),
-- 
2.39.3