[PATCH] vdpa_sim_blk: add support for VIRTIO_BLK_T_FLUSH

[Stefano Garzarella]

The simulator behaves like a ramdisk, so we don't have to do
anything when a VIRTIO_BLK_T_FLUSH request is received, but it
could be useful to test driver behavior.

Let's expose the VIRTIO_BLK_F_FLUSH feature to inform the driver
that we support the flush command.

Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
---
 drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
index 42d401d43911..a6dd1233797c 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
@@ -25,6 +25,7 @@
 #define DRV_LICENSE  "GPL v2"
 
 #define VDPASIM_BLK_FEATURES	(VDPASIM_FEATURES | \
+				 (1ULL << VIRTIO_BLK_F_FLUSH)    | \
 				 (1ULL << VIRTIO_BLK_F_SIZE_MAX) | \
 				 (1ULL << VIRTIO_BLK_F_SEG_MAX)  | \
 				 (1ULL << VIRTIO_BLK_F_BLK_SIZE) | \
@@ -166,6 +167,17 @@ static bool vdpasim_blk_handle_req(struct vdpasim *vdpasim,
 		pushed += bytes;
 		break;
 
+	case VIRTIO_BLK_T_FLUSH:
+		if (sector != 0) {
+			dev_err(&vdpasim->vdpa.dev,
+				"A driver MUST set sector to 0 for a VIRTIO_BLK_T_FLUSH request - sector: 0x%llx\n",
+				sector);
+			status = VIRTIO_BLK_S_IOERR;
+			break;
+		}
+
+		break;
+
 	default:
 		dev_warn(&vdpasim->vdpa.dev,
 			 "Unsupported request type %d\n", type);
-- 
2.35.1