Re: [PATCH net-next 1/2] net: enetc: declare NETIF_F_IP_CSUM and do it in software
From: Jakub Kicinski <kuba@kernel.org>
Date: 2021-10-07 00:24:24
On Wed, 6 Oct 2021 23:13:07 +0300 Ioana Ciornei wrote:
This is just a preparation patch for software TSO in the enetc driver. Unfortunately, ENETC does not support Tx checksum offload which would normally render TSO, even software, impossible. Declare NETIF_F_IP_CSUM as part of the feature set and do it at driver level using skb_csum_hwoffload_help() so that we can move forward and also add support for TSO in the next patch. Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Did you choose NETIF_F_IP_CSUM intentionally? It'll only support IPv4, and since you always fall back to SW I'd think NETIF_F_HW_CSUM makes more sense.
quoted hunk ↗ jump to hunk
diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c index 3cbfa8b4e265..a92bfd660f22 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c@@ -319,7 +319,7 @@ static netdev_tx_t enetc_start_xmit(struct sk_buff *skb, { struct enetc_ndev_priv *priv = netdev_priv(ndev); struct enetc_bdr *tx_ring; - int count; + int count, err; /* Queue one-step Sync packet if already locked */ if (skb->cb[0] & ENETC_F_TX_ONESTEP_SYNC_TSTAMP) {@@ -342,6 +342,12 @@ static netdev_tx_t enetc_start_xmit(struct sk_buff *skb, return NETDEV_TX_BUSY; } + if (skb->ip_summed == CHECKSUM_PARTIAL) { + err = skb_csum_hwoffload_help(skb, 0); + if (err) + goto drop_packet_err; + }
Any reason no to call skb_checksum_help() directly?