vhost scsi: add lun parser helper

Move code to parse lun from req's lun_buf to helper, so tmf code
can use it in the next patch.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/1604986403-4931-5-git-send-email-michael.christie@oracle.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
index 5d8850f..ed7dc6b 100644 (file)
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -898,6 +898,11 @@ vhost_scsi_get_req(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc,
        return ret;
 }
 
+static u16 vhost_buf_to_lun(u8 *lun_buf)
+{
+       return ((lun_buf[2] << 8) | lun_buf[3]) & 0x3FFF;
+}
+
 static void
 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 {
@@ -1036,12 +1041,12 @@ vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
                        tag = vhost64_to_cpu(vq, v_req_pi.tag);
                        task_attr = v_req_pi.task_attr;
                        cdb = &v_req_pi.cdb[0];
-                       lun = ((v_req_pi.lun[2] << 8) | v_req_pi.lun[3]) & 0x3FFF;
+                       lun = vhost_buf_to_lun(v_req_pi.lun);
                } else {
                        tag = vhost64_to_cpu(vq, v_req.tag);
                        task_attr = v_req.task_attr;
                        cdb = &v_req.cdb[0];
-                       lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
+                       lun = vhost_buf_to_lun(v_req.lun);
                }
                /*
                 * Check that the received CDB size does not exceeded our