[PATCH RFC v3 4/8] virtio_net: add supports for extended offloads
From: Paolo Abeni <pabeni@redhat.com>
Date: 2025-06-06 11:46:48
Subsystem:
networking drivers, the rest, virtio net driver · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, "Michael S. Tsirkin", Jason Wang
The virtio_net driver needs it to implement GSO over UDP tunnel offload. The only missing piece is mapping them to/from the extended features. Signed-off-by: Paolo Abeni <pabeni@redhat.com> --- v2 -> v3: - offload to feature conversion is now an inline function v1 -> v2: - drop unused macro - restrict the offload remap range as per latest spec update --- drivers/net/virtio_net.c | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index e53ba600605a..18ad50de4928 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c@@ -35,6 +35,22 @@ module_param(csum, bool, 0444); module_param(gso, bool, 0444); module_param(napi_tx, bool, 0644); +#define VIRTIO_OFFLOAD_MAP_MIN 46 +#define VIRTIO_OFFLOAD_MAP_MAX 47 +#define VIRTIO_FEATURES_MAP_MIN 65 +#define VIRTIO_O2F_DELTA (VIRTIO_FEATURES_MAP_MIN - VIRTIO_OFFLOAD_MAP_MIN) + +static bool virtio_is_mapped_offload(unsigned int obit) +{ + return obit >= VIRTIO_OFFLOAD_MAP_MIN && + obit <= VIRTIO_OFFLOAD_MAP_MAX; +} + +static unsigned int virtio_offload_to_feature(unsigned int obit) +{ + return virtio_is_mapped_offload(obit) ? obit + VIRTIO_O2F_DELTA : obit; +} + /* FIXME: MTU in config. */ #define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN) #define GOOD_COPY_LEN 128
@@ -7037,9 +7053,13 @@ static int virtnet_probe(struct virtio_device *vdev) netif_carrier_on(dev); } - for (i = 0; i < ARRAY_SIZE(guest_offloads); i++) - if (virtio_has_feature(vi->vdev, guest_offloads[i])) + for (i = 0; i < ARRAY_SIZE(guest_offloads); i++) { + unsigned int fbit; + + fbit = virtio_offload_to_feature(guest_offloads[i]); + if (virtio_has_feature(vi->vdev, fbit)) set_bit(guest_offloads[i], &vi->guest_offloads); + } vi->guest_offloads_capable = vi->guest_offloads; rtnl_unlock();
--
2.49.0