[dpdk-dev] [PATCH v2 1/3] vhost: disable reply-ack protocol feature if iommu feature disabled
Maxime Coquelin
maxime.coquelin at redhat.com
Mon Nov 6 21:38:10 CET 2017
If the application has disabled VIRTIO_F_IOMMU_PLATFORM, disable
VHOST_USER_PROTOCOL_F_REPLY_ACK protocol feature that is only
mandatory with IOMMU for now.
This is done to provide a way for the application to support
multiqueue with old Qemu versions (v2.7.0 to v2.9.0) that have
reply-ack feature broken.
Signed-off-by: Maxime Coquelin <maxime.coquelin at redhat.com>
---
lib/librte_vhost/vhost_user.c | 24 ++++++++++++++++++++++--
1 file changed, 22 insertions(+), 2 deletions(-)
diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
index 1f6cba4b9..e35218688 100644
--- a/lib/librte_vhost/vhost_user.c
+++ b/lib/librte_vhost/vhost_user.c
@@ -878,6 +878,27 @@ vhost_user_set_vring_enable(struct virtio_net **pdev,
}
static void
+vhost_user_get_protocol_features(struct virtio_net *dev,
+ struct VhostUserMsg *msg)
+{
+ uint64_t features, protocol_features = VHOST_USER_PROTOCOL_FEATURES;
+
+ rte_vhost_driver_get_features(dev->ifname, &features);
+
+ /*
+ * REPLY_ACK protocol feature is only mandatory for now
+ * for IOMMU feature. If IOMMU is explicitly disabled by the
+ * application, disable also REPLY_ACK feature for older buggy
+ * Qemu versions (from v2.7.0 to v2.9.0).
+ */
+ if (!(features & (1ULL << VIRTIO_F_IOMMU_PLATFORM)))
+ protocol_features &= ~(1ULL << VHOST_USER_PROTOCOL_F_REPLY_ACK);
+
+ msg->payload.u64 = protocol_features;
+ msg->size = sizeof(msg->payload.u64);
+}
+
+static void
vhost_user_set_protocol_features(struct virtio_net *dev,
uint64_t protocol_features)
{
@@ -1248,8 +1269,7 @@ vhost_user_msg_handler(int vid, int fd)
break;
case VHOST_USER_GET_PROTOCOL_FEATURES:
- msg.payload.u64 = VHOST_USER_PROTOCOL_FEATURES;
- msg.size = sizeof(msg.payload.u64);
+ vhost_user_get_protocol_features(dev, &msg);
send_vhost_reply(fd, &msg);
break;
case VHOST_USER_SET_PROTOCOL_FEATURES:
--
2.13.6
More information about the dev
mailing list