Implement tx checksum kfunc for veth by checksumming the packet
in software (since there is nothing to offload). The change mostly
exists to make it possible to have software-based selftest.
Probably should instead set csum_start/csum_offset on the skb
itself?
Signed-off-by: Stanislav Fomichev <sdf@xxxxxxxxxx>
---
drivers/net/veth.c | 29 +++++++++++++++++++++++++++++
1 file changed, 29 insertions(+)
diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index 5af4b15e107c..6f97511a545b 100644
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c
@@ -1814,6 +1814,34 @@ static int veth_devtx_tx_timestamp(const struct devtx_ctx *_ctx, u64 *timestamp)
return 0;
}
+static int veth_devtx_request_l4_csum(const struct devtx_ctx *_ctx,
+ u16 csum_start, u16 csum_offset)
+{
+ struct veth_devtx_ctx *ctx = (struct veth_devtx_ctx *)_ctx;
+ struct sk_buff *skb = ctx->skb;
+ __wsum csum;
+ int ret;
+
+ if (!skb)
+ return -EINVAL;
+
+ if (skb_transport_header_was_set(skb))
+ return -EINVAL;
+
+ if (csum_start >= skb->len)
+ return -EINVAL;
+
+ ret = skb_ensure_writable(skb, csum_offset + sizeof(__sum16));
+ if (ret)
+ return ret;
+
+ csum = csum_partial(skb->data + csum_start, skb->len - csum_start, 0);
+ *(__sum16 *)(skb->data + csum_offset) = csum_fold(csum) ?: CSUM_MANGLED_0;
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+ return 0;
+}
+
static const struct net_device_ops veth_netdev_ops = {
.ndo_init = veth_dev_init,
.ndo_open = veth_open,
@@ -1840,6 +1868,7 @@ static const struct xdp_metadata_ops veth_xdp_metadata_ops = {
.xmo_rx_hash = veth_xdp_rx_hash,
.xmo_request_tx_timestamp = veth_devtx_request_tx_timestamp,
.xmo_tx_timestamp = veth_devtx_tx_timestamp,
+ .xmo_request_l4_checksum = veth_devtx_request_l4_csum,
};
#define VETH_FEATURES (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HW_CSUM | \
--
2.41.0.255.g8b1d071c50-goog
