[PATCH 1/2] vhost: fix vduse features negotiation

[Maxime Coquelin]

The series introducing VDUSE support missed the
application capability to disable supported features.

This results in TSO being negotiated while not supported by
the application.

Fixes: 0adb8eccc6a6 ("vhost: add VDUSE device creation and destruction")

Signed-off-by: Maxime Coquelin <maxime.coquelin at redhat.com>
---
 lib/vhost/socket.c | 19 +++++++++++++------
 lib/vhost/vduse.c  | 28 +++++++---------------------
 lib/vhost/vduse.h  | 20 ++++++++++++++++++++
 3 files changed, 40 insertions(+), 27 deletions(-)

diff --git a/lib/vhost/socket.c b/lib/vhost/socket.c
index 19a7469e45..a65d301406 100644
--- a/lib/vhost/socket.c
+++ b/lib/vhost/socket.c
@@ -921,6 +921,10 @@ rte_vhost_driver_register(const char *path, uint64_t flags)
 		VHOST_LOG_CONFIG(path, ERR, "failed to init connection mutex\n");
 		goto out_free;
 	}
+
+	if (!strncmp("/dev/vduse/", path, strlen("/dev/vduse/")))
+		vsocket->is_vduse = true;
+
 	vsocket->vdpa_dev = NULL;
 	vsocket->max_queue_pairs = VHOST_MAX_QUEUE_PAIRS;
 	vsocket->extbuf = flags & RTE_VHOST_USER_EXTBUF_SUPPORT;
@@ -950,9 +954,14 @@ rte_vhost_driver_register(const char *path, uint64_t flags)
 	 * two values.
 	 */
 	vsocket->use_builtin_virtio_net = true;
-	vsocket->supported_features = VIRTIO_NET_SUPPORTED_FEATURES;
-	vsocket->features           = VIRTIO_NET_SUPPORTED_FEATURES;
-	vsocket->protocol_features  = VHOST_USER_PROTOCOL_FEATURES;
+	if (vsocket->is_vduse) {
+		vsocket->supported_features = VDUSE_NET_SUPPORTED_FEATURES;
+		vsocket->features           = VDUSE_NET_SUPPORTED_FEATURES;
+	} else {
+		vsocket->supported_features = VIRTIO_NET_SUPPORTED_FEATURES;
+		vsocket->features           = VIRTIO_NET_SUPPORTED_FEATURES;
+		vsocket->protocol_features  = VHOST_USER_PROTOCOL_FEATURES;
+	}
 
 	if (vsocket->async_copy) {
 		vsocket->supported_features &= ~(1ULL << VHOST_F_LOG_ALL);
@@ -993,9 +1002,7 @@ rte_vhost_driver_register(const char *path, uint64_t flags)
 #endif
 	}
 
-	if (!strncmp("/dev/vduse/", path, strlen("/dev/vduse/"))) {
-		vsocket->is_vduse = true;
-	} else {
+	if (!vsocket->is_vduse) {
 		if ((flags & RTE_VHOST_USER_CLIENT) != 0) {
 			vsocket->reconnect = !(flags & RTE_VHOST_USER_NO_RECONNECT);
 			if (vsocket->reconnect && reconn_tid == 0) {
diff --git a/lib/vhost/vduse.c b/lib/vhost/vduse.c
index a509daf80c..1478562be1 100644
--- a/lib/vhost/vduse.c
+++ b/lib/vhost/vduse.c
@@ -26,26 +26,6 @@
 #define VHOST_VDUSE_API_VERSION 0
 #define VDUSE_CTRL_PATH "/dev/vduse/control"
 
-#define VDUSE_NET_SUPPORTED_FEATURES ((1ULL << VIRTIO_NET_F_MRG_RXBUF) | \
-				(1ULL << VIRTIO_F_ANY_LAYOUT) | \
-				(1ULL << VIRTIO_F_VERSION_1)   | \
-				(1ULL << VIRTIO_NET_F_GSO) | \
-				(1ULL << VIRTIO_NET_F_HOST_TSO4) | \
-				(1ULL << VIRTIO_NET_F_HOST_TSO6) | \
-				(1ULL << VIRTIO_NET_F_HOST_UFO) | \
-				(1ULL << VIRTIO_NET_F_HOST_ECN) | \
-				(1ULL << VIRTIO_NET_F_CSUM)    | \
-				(1ULL << VIRTIO_NET_F_GUEST_CSUM) | \
-				(1ULL << VIRTIO_NET_F_GUEST_TSO4) | \
-				(1ULL << VIRTIO_NET_F_GUEST_TSO6) | \
-				(1ULL << VIRTIO_NET_F_GUEST_UFO) | \
-				(1ULL << VIRTIO_NET_F_GUEST_ECN) | \
-				(1ULL << VIRTIO_RING_F_INDIRECT_DESC) | \
-				(1ULL << VIRTIO_F_IN_ORDER) | \
-				(1ULL << VIRTIO_F_IOMMU_PLATFORM) | \
-				(1ULL << VIRTIO_NET_F_CTRL_VQ) | \
-				(1ULL << VIRTIO_NET_F_MQ))
-
 struct vduse {
 	struct fdset fdset;
 };
@@ -440,7 +420,7 @@ vduse_device_create(const char *path)
 	struct virtio_net *dev;
 	struct virtio_net_config vnet_config = { 0 };
 	uint64_t ver = VHOST_VDUSE_API_VERSION;
-	uint64_t features = VDUSE_NET_SUPPORTED_FEATURES;
+	uint64_t features;
 	struct vduse_dev_config *dev_config = NULL;
 	const char *name = path + strlen("/dev/vduse/");
 
@@ -488,6 +468,12 @@ vduse_device_create(const char *path)
 		goto out_ctrl_close;
 	}
 
+	ret = rte_vhost_driver_get_features(path, &features);
+	if (ret < 0) {
+		VHOST_LOG_CONFIG(name, ERR, "Failed to get backend features\n");
+		goto out_free;
+	}
+
 	ret = rte_vhost_driver_get_queue_num(path, &max_queue_pairs);
 	if (ret < 0) {
 		VHOST_LOG_CONFIG(name, ERR, "Failed to get max queue pairs\n");
diff --git a/lib/vhost/vduse.h b/lib/vhost/vduse.h
index a15e5d4c16..cd55bfd858 100644
--- a/lib/vhost/vduse.h
+++ b/lib/vhost/vduse.h
@@ -7,6 +7,26 @@
 
 #include "vhost.h"
 
+#define VDUSE_NET_SUPPORTED_FEATURES ((1ULL << VIRTIO_NET_F_MRG_RXBUF) | \
+				(1ULL << VIRTIO_F_ANY_LAYOUT) | \
+				(1ULL << VIRTIO_F_VERSION_1)   | \
+				(1ULL << VIRTIO_NET_F_GSO) | \
+				(1ULL << VIRTIO_NET_F_HOST_TSO4) | \
+				(1ULL << VIRTIO_NET_F_HOST_TSO6) | \
+				(1ULL << VIRTIO_NET_F_HOST_UFO) | \
+				(1ULL << VIRTIO_NET_F_HOST_ECN) | \
+				(1ULL << VIRTIO_NET_F_CSUM)    | \
+				(1ULL << VIRTIO_NET_F_GUEST_CSUM) | \
+				(1ULL << VIRTIO_NET_F_GUEST_TSO4) | \
+				(1ULL << VIRTIO_NET_F_GUEST_TSO6) | \
+				(1ULL << VIRTIO_NET_F_GUEST_UFO) | \
+				(1ULL << VIRTIO_NET_F_GUEST_ECN) | \
+				(1ULL << VIRTIO_RING_F_INDIRECT_DESC) | \
+				(1ULL << VIRTIO_F_IN_ORDER) | \
+				(1ULL << VIRTIO_F_IOMMU_PLATFORM) | \
+				(1ULL << VIRTIO_NET_F_CTRL_VQ) | \
+				(1ULL << VIRTIO_NET_F_MQ))
+
 #ifdef VHOST_HAS_VDUSE
 
 int vduse_device_create(const char *path);
-- 
2.41.0