Commit 0ce8df66 authored by Edward Cree's avatar Edward Cree Committed by David S. Miller
Browse files

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: default avatarEdward Cree <ecree@solarflare.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 1679c72c

drivers/net/ethernet/sfc/ef10.c

+41 −14
Original line number Diff line number Diff line
@@ -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;

	}



	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);

drivers/net/ethernet/sfc/net_driver.h

+5 −0
Original line number Diff line number Diff line
@@ -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;