This series adds support to new Virtio's MTU feature[1]. The MTU value is set via QEMU parameters.
If the feature is negotiated (i.e supported by both host andcguest, and valid MTU value is set in QEMU via its host_mtu parameter), QEMU shares the configured MTU value throught dedicated Vhost protocol feature. On vhost side, the value is stored in the virtio_net structure, and made available to the application thanks to new vhost lib's rte_vhost_mtu_get() function. To be able to set eth_dev's MTU value at the right time, i.e. to call rte_vhost_mtu_get() just after Virtio features have been negotiated and before the device is really started, a new vhost flag has been introduced (VIRTIO_DEV_READY), because the VIRTIO_DEV_RUNNING flag is set too late (after .new_device() ops is called). Regarding valid MTU values, the maximum MTU value accepted on vhost side is 65535 bytes, as defined in Virtio Spec and supported in Virtio-net Kernel driver. But in Virtio PMD, current maximum frame size is 9728 bytes (~9700 bytes MTU). So maximum MTU size accepted in Virtio PMD is the minimum between ~9700 bytes and host's MTU. Finally, this series also adds MTU value printing in testpmd's "show port info" command when non-zero. This series target v17.05 release. Cheers, Maxime [1]: https://lists.oasis-open.org/archives/virtio-dev/201609/msg00128.html Changes since v1: ----------------- * Rebased on top of v17.02 * Virtio PMD: ensure MTU value is valid before ack'ing the feature (Aaron) * Vhost lib/PMD: Remove MTU setting API/op (Yuanhan) Maxime Coquelin (7): vhost: Enable VIRTIO_NET_F_MTU feature vhost: vhost-user: Add MTU protocol feature support vhost: Add new ready status flag vhost: Add API to get MTU value net/vhost: Fill rte_eth_dev's MTU property net/virtio: Add MTU feature support app/testpmd: print MTU value in show port info app/test-pmd/config.c | 5 +++++ doc/guides/nics/features/virtio.ini | 1 + drivers/net/vhost/rte_eth_vhost.c | 2 ++ drivers/net/virtio/virtio_ethdev.c | 45 +++++++++++++++++++++++++++++++++++-- drivers/net/virtio/virtio_ethdev.h | 3 ++- drivers/net/virtio/virtio_pci.h | 3 +++ lib/librte_vhost/rte_virtio_net.h | 15 +++++++++++++ lib/librte_vhost/vhost.c | 22 +++++++++++++++++- lib/librte_vhost/vhost.h | 9 +++++++- lib/librte_vhost/vhost_user.c | 44 ++++++++++++++++++++++++++++++------ lib/librte_vhost/vhost_user.h | 5 ++++- 11 files changed, 141 insertions(+), 13 deletions(-) -- 2.9.3
