s390x: Share image between qemu instances

This commit enables the `share-rw` flag for the image file in s390x.
This enables multiple instances of qemu to share the same image.

Fixes: #2049

Signed-off-by: Jan Schintag <jan.schintag@de.ibm.com>

virtcontainers/device/config/config.go

@@ -144,6 +144,9 @@ type BlockDrive struct {
 
 	// DevNo identifies the css bus id for virtio-blk-ccw
 	DevNo string
+
+	// ShareRW enables multiple qemu instances to share the File
+	ShareRW bool
 }
 
 // VFIODeviceType indicates VFIO device type

virtcontainers/qemu_arch_base.go

@@ -548,6 +548,7 @@ func genericBlockDevice(drive config.BlockDrive, nestedRun bool) (govmmQemu.Bloc
 		Format:        govmmQemu.BlockDeviceFormat(drive.Format),
 		Interface:     "none",
 		DisableModern: nestedRun,
+		ShareRW:       drive.ShareRW,
 	}, nil
 }
 

virtcontainers/qemu_s390x.go

@@ -131,6 +131,7 @@ func (q *qemuS390x) appendImage(devices []govmmQemu.Device, path string) ([]govm
 	if err != nil {
 		return nil, err
 	}
+	drive.ShareRW = true
 	devices, err = q.appendBlockDevice(devices, drive)
 	if err != nil {
 		return nil, err