From 0ce8df6614568cfb390756cac35ac690105181f5 Mon Sep 17 00:00:00 2001 From: Edward Cree Date: Fri, 11 Sep 2020 23:40:14 +0100 Subject: [PATCH] sfc: implement encapsulated TSO on EF10 >From the 8000 series onwards, EF10 NICs with suitable firmware are able to perform TSO within VXLAN or NVGRE encapsulation. Signed-off-by: Edward Cree Signed-off-by: David S. Miller --- drivers/net/ethernet/sfc/ef10.c | 55 ++++++++++++++++++++++++++--------- drivers/net/ethernet/sfc/net_driver.h | 5 ++++ 2 files changed, 46 insertions(+), 14 deletions(-) diff --git a/drivers/net/ethernet/sfc/ef10.c b/drivers/net/ethernet/sfc/ef10.c index c6507d1..4775b82 100644 --- a/drivers/net/ethernet/sfc/ef10.c +++ b/drivers/net/ethernet/sfc/ef10.c @@ -2179,10 +2179,11 @@ int efx_ef10_tx_tso_desc(struct efx_tx_queue *tx_queue, struct sk_buff *skb, bool *data_mapped) { struct efx_tx_buffer *buffer; + u16 inner_ipv4_id = 0; + u16 outer_ipv4_id = 0; struct tcphdr *tcp; struct iphdr *ip; - - u16 ipv4_id; + u16 ip_tot_len; u32 seqnum; u32 mss; @@ -2195,21 +2196,43 @@ int efx_ef10_tx_tso_desc(struct efx_tx_queue *tx_queue, struct sk_buff *skb, return -EINVAL; } - ip = ip_hdr(skb); + if (skb->encapsulation) { + if (!tx_queue->tso_encap) + return -EINVAL; + ip = ip_hdr(skb); + if (ip->version == 4) + outer_ipv4_id = ntohs(ip->id); + + ip = inner_ip_hdr(skb); + tcp = inner_tcp_hdr(skb); + } else { + ip = ip_hdr(skb); + tcp = tcp_hdr(skb); + } + + /* 8000-series EF10 hardware requires that IP Total Length be + * greater than or equal to the value it will have in each segment + * (which is at most mss + 208 + TCP header length), but also less + * than (0x10000 - inner_network_header). Otherwise the TCP + * checksum calculation will be broken for encapsulated packets. + * We fill in ip->tot_len with 0xff30, which should satisfy the + * first requirement unless the MSS is ridiculously large (which + * should be impossible as the driver max MTU is 9216); it is + * guaranteed to satisfy the second as we only attempt TSO if + * inner_network_header <= 208. + */ + ip_tot_len = -EFX_TSO2_MAX_HDRLEN; + EFX_WARN_ON_ONCE_PARANOID(mss + EFX_TSO2_MAX_HDRLEN + + (tcp->doff << 2u) > ip_tot_len); + if (ip->version == 4) { - /* Modify IPv4 header if needed. */ - ip->tot_len = 0; + ip->tot_len = htons(ip_tot_len); ip->check = 0; - ipv4_id = ntohs(ip->id); + inner_ipv4_id = ntohs(ip->id); } else { - /* Modify IPv6 header if needed. */ - struct ipv6hdr *ipv6 = ipv6_hdr(skb); - - ipv6->payload_len = 0; - ipv4_id = 0; + ((struct ipv6hdr *)ip)->payload_len = htons(ip_tot_len); } - tcp = tcp_hdr(skb); seqnum = ntohl(tcp->seq); buffer = efx_tx_queue_get_insert_buffer(tx_queue); @@ -2222,7 +2245,7 @@ int efx_ef10_tx_tso_desc(struct efx_tx_queue *tx_queue, struct sk_buff *skb, ESF_DZ_TX_OPTION_TYPE, ESE_DZ_TX_OPTION_DESC_TSO, ESF_DZ_TX_TSO_OPTION_TYPE, ESE_DZ_TX_TSO_OPTION_DESC_FATSO2A, - ESF_DZ_TX_TSO_IP_ID, ipv4_id, + ESF_DZ_TX_TSO_IP_ID, inner_ipv4_id, ESF_DZ_TX_TSO_TCP_SEQNO, seqnum ); ++tx_queue->insert_count; @@ -2232,11 +2255,12 @@ int efx_ef10_tx_tso_desc(struct efx_tx_queue *tx_queue, struct sk_buff *skb, buffer->flags = EFX_TX_BUF_OPTION; buffer->len = 0; buffer->unmap_len = 0; - EFX_POPULATE_QWORD_4(buffer->option, + EFX_POPULATE_QWORD_5(buffer->option, ESF_DZ_TX_DESC_IS_OPT, 1, ESF_DZ_TX_OPTION_TYPE, ESE_DZ_TX_OPTION_DESC_TSO, ESF_DZ_TX_TSO_OPTION_TYPE, ESE_DZ_TX_TSO_OPTION_DESC_FATSO2B, + ESF_DZ_TX_TSO_OUTER_IPID, outer_ipv4_id, ESF_DZ_TX_TSO_TCP_MSS, mss ); ++tx_queue->insert_count; @@ -2322,6 +2346,9 @@ static void efx_ef10_tx_init(struct efx_tx_queue *tx_queue) ESF_DZ_TX_TIMESTAMP, tx_queue->timestamping); tx_queue->write_count = 1; + if (tx_queue->tso_version == 2 && efx_has_cap(efx, TX_TSO_V2_ENCAP)) + tx_queue->tso_encap = true; + wmb(); efx_ef10_push_tx_desc(tx_queue, txd); diff --git a/drivers/net/ethernet/sfc/net_driver.h b/drivers/net/ethernet/sfc/net_driver.h index ddcd1c4..a4c0445 100644 --- a/drivers/net/ethernet/sfc/net_driver.h +++ b/drivers/net/ethernet/sfc/net_driver.h @@ -77,6 +77,9 @@ /* Minimum MTU, from RFC791 (IP) */ #define EFX_MIN_MTU 68 +/* Maximum total header length for TSOv2 */ +#define EFX_TSO2_MAX_HDRLEN 208 + /* Size of an RX scatter buffer. Small enough to pack 2 into a 4K page, * and should be a multiple of the cache line size. */ @@ -195,6 +198,7 @@ struct efx_tx_buffer { * Is our index within @channel->tx_queue array. * @type: configuration type of this TX queue. A bitmask of %EFX_TXQ_TYPE_* flags. * @tso_version: Version of TSO in use for this queue. + * @tso_encap: Is encapsulated TSO supported? Supported in TSOv2 on 8000 series. * @channel: The associated channel * @core_txq: The networking core TX queue structure * @buffer: The software buffer ring @@ -258,6 +262,7 @@ struct efx_tx_queue { unsigned int label; unsigned int type; unsigned int tso_version; + bool tso_encap; struct efx_channel *channel; struct netdev_queue *core_txq; struct efx_tx_buffer *buffer; -- 2.7.4