Date: Sun, 18 Nov 2012 14:23:35 +0000 (UTC) From: Andre Oppermann <andre@FreeBSD.org> To: src-committers@freebsd.org, svn-src-user@freebsd.org Subject: svn commit: r243229 - in user/andre/tcp_workqueue/sys: dev/e1000 dev/ixgbe sys Message-ID: <201211181423.qAIENZUo042424@svn.freebsd.org>
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Author: andre Date: Sun Nov 18 14:23:35 2012 New Revision: 243229 URL: http://svnweb.freebsd.org/changeset/base/243229 Log: After careful studying of our historic checksum offload capabilities, a number datasheets for modern high performance NICs and the NDIS 6.x documentation re-arrange and re-structure our checksum offload framework to better support available capabilities and to prepare for future ones. The input checksumming path, where the NIC has verified certain L3+L4 checksums, is simplified and no longer overlaying the output offload bits. This greatly reduces confusion. The output offloading capabilities path is clearly structured into the participating layers and improves naming of the options to reduce confusion here too. Also document the assumptions and guarantees made by the stack and at the driver boundary. Clean up a few CSUM definitions in drivers I already messed with. Modified: user/andre/tcp_workqueue/sys/dev/e1000/if_igb.c user/andre/tcp_workqueue/sys/dev/ixgbe/ixgbe.c user/andre/tcp_workqueue/sys/dev/ixgbe/ixv.c user/andre/tcp_workqueue/sys/sys/mbuf.h Modified: user/andre/tcp_workqueue/sys/dev/e1000/if_igb.c ============================================================================== --- user/andre/tcp_workqueue/sys/dev/e1000/if_igb.c Sun Nov 18 14:21:05 2012 (r243228) +++ user/andre/tcp_workqueue/sys/dev/e1000/if_igb.c Sun Nov 18 14:23:35 2012 (r243229) @@ -4945,7 +4945,7 @@ igb_rx_checksum(u32 staterr, struct mbuf } if (status & (E1000_RXD_STAT_TCPCS | E1000_RXD_STAT_UDPCS)) { - u16 type = (CSUM_DATA_VALID | CSUM_PSEUDO_HDR); + u32 type = (CSUM_DATA_VALID | CSUM_PSEUDO_HDR); #if __FreeBSD_version >= 800000 if (sctp) /* reassign */ type = CSUM_SCTP_VALID; Modified: user/andre/tcp_workqueue/sys/dev/ixgbe/ixgbe.c ============================================================================== --- user/andre/tcp_workqueue/sys/dev/ixgbe/ixgbe.c Sun Nov 18 14:21:05 2012 (r243228) +++ user/andre/tcp_workqueue/sys/dev/ixgbe/ixgbe.c Sun Nov 18 14:23:35 2012 (r243229) @@ -1823,7 +1823,7 @@ ixgbe_xmit(struct tx_ring *txr, struct m if ((m_head->m_flags & M_VLANTAG) || (m_head->m_pkthdr.csum_flags & (CSUM_IP|CSUM_TCP|CSUM_TCP_IPV6|CSUM_TSO|CSUM_UDP|CSUM_UDP_IPV6| - CSUM_UFO|CSUM_SCTP|CSUM_SCTP_IPV6))) { + CSUM_SCTP|CSUM_SCTP_IPV6))) { if (ixgbe_offload_setup(txr, m_head, &cmd_type_len, &olinfo_status)) ++adapter->tso_tx; @@ -3328,7 +3328,7 @@ ixgbe_offload_setup(struct tx_ring *txr, l4_hlen = sizeof(struct udphdr); if (m->m_pkthdr.csum_flags & (CSUM_UDP | CSUM_UDP_IPV6)) *olinfo_status |= IXGBE_TXD_POPTS_TXSM << 8; - if (m->m_pkthdr.csum_flags & (CSUM_UFO | 0)) { + if (m->m_pkthdr.csum_flags & (CSUM_IP_UFO | 0)) { *cmd_type_len |= IXGBE_ADVTXD_DCMD_TSE; paylen -= ehdrlen + ip_hlen + l4_hlen; } @@ -4722,7 +4722,7 @@ ixgbe_rx_checksum(u32 staterr, struct mb mp->m_pkthdr.csum_flags = 0; } if (status & IXGBE_RXD_STAT_L4CS) { - u16 type = (CSUM_DATA_VALID | CSUM_PSEUDO_HDR); + u32 type = (CSUM_DATA_VALID | CSUM_PSEUDO_HDR); #if __FreeBSD_version >= 800000 if (sctp) type = CSUM_SCTP_VALID; Modified: user/andre/tcp_workqueue/sys/dev/ixgbe/ixv.c ============================================================================== --- user/andre/tcp_workqueue/sys/dev/ixgbe/ixv.c Sun Nov 18 14:21:05 2012 (r243228) +++ user/andre/tcp_workqueue/sys/dev/ixgbe/ixv.c Sun Nov 18 14:23:35 2012 (r243229) @@ -3554,7 +3554,7 @@ ixv_rx_checksum(u32 staterr, struct mbuf mp->m_pkthdr.csum_flags = 0; } if (status & IXGBE_RXD_STAT_L4CS) { - u16 type = (CSUM_DATA_VALID | CSUM_PSEUDO_HDR); + u32 type = (CSUM_DATA_VALID | CSUM_PSEUDO_HDR); #if __FreeBSD_version >= 800000 if (sctp) type = CSUM_SCTP_VALID; Modified: user/andre/tcp_workqueue/sys/sys/mbuf.h ============================================================================== --- user/andre/tcp_workqueue/sys/sys/mbuf.h Sun Nov 18 14:21:05 2012 (r243228) +++ user/andre/tcp_workqueue/sys/sys/mbuf.h Sun Nov 18 14:23:35 2012 (r243229) @@ -287,32 +287,117 @@ struct mbuf { /* * Flags indicating hw checksum support and sw checksum requirements. This * field can be directly tested against if_data.ifi_hwassist. - */ -#define CSUM_IP 0x0001 /* will csum IP */ -#define CSUM_TCP 0x0002 /* will csum TCP */ -#define CSUM_UDP 0x0004 /* will csum UDP */ -#define CSUM_IPFRAG 0x0008 /* IP fragmentation offload */ -#define CSUM_UFO 0x0010 /* UDP fragmentation offload */ -#define CSUM_TSO 0x0020 /* TCP segmentation offload */ -#define CSUM_SCTP 0x0040 /* will csum SCTP */ -#define CSUM_SCTP_IPV6 0x0080 /* will csum IPv6/SCTP */ - -#define CSUM_IP_CHECKED 0x0100 /* did csum IP */ -#define CSUM_IP_VALID 0x0200 /* ... the csum is valid */ -#define CSUM_DATA_VALID 0x0400 /* csum_data field is valid */ -#define CSUM_PSEUDO_HDR 0x0800 /* csum_data has pseudo hdr */ -#define CSUM_SCTP_VALID 0x1000 /* SCTP checksum is valid */ -#define CSUM_UDP_IPV6 0x2000 /* will csum IPv6/UDP */ -#define CSUM_TCP_IPV6 0x4000 /* will csum IPv6/TCP */ -/* CSUM_TSO_IPV6 0x8000 will do IPv6/TSO */ - -/* CSUM_FRAGMENT_IPV6 0x10000 will do IPv6 fragementation */ + * + * The offloading flags are used on the inbound and outbound packet path. + * These two path behave differently. + * Please note that the IPv6 header doesn't have a checksum. + * + * Inbound: + * The NIC can support calculation of the checksum of the IP header, UDP, + * TCP and SCTP checksums. When the hardware calculated the checksum of + * the L3 or L4 header it sets the CALCULATED bit. If the calculated + * checksum also matches the original checksum in the packet it sets th + * VALID bit. The VALID bit MUST NOT be set without the corresponding + * CALCULATED bit. All L3+ packets, even with mismatched checksums are + * delivered up the network stack. The protocol specific input routines + * then can drop the packet. When doing L3 forwarding only the L3 checksum + * must be checked, a packet is to be forwarded even if the L4 checksum has + * a mismatch. + * The protocol type (eg. IPv4 or IPv6; UDP, TCP or SCTP) doesn't have to + * be stored in the bits because it follows from the packet content. + * XXXAO: See how encapsulated checksum verification can be handled. + * + * NB: A driver MUST NOT do checksumming in software just to set the checksum + * offload bits. + * NB: A driver MUST NOT set any of the CALCULATED or VALID bits if it didn't + * actually perform the nescessary checksum calculations. + * + * Outbound: + * The NIC can support calculation and insertion of the IP header, UDP, + * TCP and SCTP checksums. Additionally it can support segmentation of + * large TCP sends and IP level fragmentation of large UDP packets. + * The TCP and UDP layers generally calculate only the pseudo checksum + * WITHOUT a length value and put it into the L4 header checksum field. + * The same checksum value is also put into the csum_pseudo field. SCTP + * (thankfully) doesn't include a pseudo header in its checksum. The + * NIC may ignore the pseudo header checksum and do its own calculations + * entirely based on the packet content. + * + * More advanced features are TCP segmentation offload and UDP fragmentation + * offload. Whenever these flags are set, the upper layers will set the + * csum_l(2-4)hlen fields. The aggregated sum of the header length will + * be present contiguously in the first mbuf. The csum_pseudo is as before. + * Packets for segmentation/fragmentation do not exceed IP_MAXLEN (64K) + * including L3 headers. However the additional L2 headers come on top + * and put the entire frame above 64K. This has to be accounted for in + * the driver and its DMA setup. Segmentation and fragmentation features + * are protocol dependent and each protocol has to be defined. + * L4 seg/fragmentation offload always implies L4 and L3 checksum offloading + * as well. However they are always explicitly specified as well. + * + * NB: A driver can blindly verify the above to be true and simply test + * the first mbuf's length againt the aggregated csum_l(2-4)hlen. If is + * too short it can just drop the packet and return EINVAL. Additionally + * it should verify the mbuf chain's intergrity with m_sanity() in a KASSERT. + */ + +/* Inbound flags. */ +#define MCSUM_INFLAGS(m) ((m)->csum_flags & \ + 0xF0000000) + +#define CSUM_L3_CALC 0x10000000 /* IP hdr csum calculated */ +#define CSUM_L3_VALID 0x20000000 /* IP hdr csum equal calculated */ +#define CSUM_L4_CALC 0x40000000 /* UDP/TCP/SCTP csum calculated */ +#define CSUM_L4_VALID 0x80000000 /* UDP/TCP/SCTP csum eq. calc. */ + +/* Outboud flags, tested against ifi_hwassist. */ +#define MCSUM_OUTFLAGS(m) ((m)->csum_flags & \ + 0x0FFFFFF0) + +/* IPv4 csum offload 0x0000---0 */ +#define CSUM_IP 0x00000010 /* will csum IP header */ +#define CSUM_IP_UDP 0x00000030 /* will csum UDP */ +#define CSUM_IP_TCP 0x00000050 /* will csum TCP */ +#define CSUM_IP_SCTP 0x00000090 /* will csum SCTP */ + +#define CSUM_IP_FRAGO 0x00000110 /* IP fragmentation offload */ +#define CSUM_IP_UFO 0x00000230 /* UDP fragmentation offload */ +#define CSUM_IP_TSO 0x00000450 /* TCP segmentation offload */ +#define CSUM_IP_SCO 0x00000890 /* SCTP chunking offload */ + +/* IPv6 csum offload 0x0---0000 */ + /* IPv6 hdr has no csum */ +#define CSUM_IP6_UDP 0x00020000 /* will csum IPv6/UDP */ +#define CSUM_IP6_TCP 0x00040000 /* will csum IPv6/TCP */ +#define CSUM_IP6_SCTP 0x00080000 /* will csum IPv6/SCTP */ + +#define CSUM_IP6_FRAGO 0x00200000 /* IPv6 frag */ +#define CSUM_IP6_UFO 0x00220000 /* IPv6/UFO */ +#define CSUM_IP6_TSO 0x00440000 /* IPv6/TSO */ +#define CSUM_IP6_SCO 0x00880000 * SCTP chunk offload */ + +#define CSUM_RSS_HT_XX 0x00000001-F + +/* Definition compatiblity with < 20121118, goes away after tree pruning */ +#define CSUM_UDP CSUM_IP_UDP +#define CSUM_TCP CSUM_IP_TCP +#define CSUM_SCTP CSUM_IP_SCTP +#define CSUM_TSO CSUM_IP_TSO +#define CSUM_IPFRAG CSUM_IP_FRAGO +#define CSUM_UDP_IPV6 CSUM_IP6_UDP /* will csum IPv6/UDP */ +#define CSUM_TCP_IPV6 CSUM_IP6_TCP /* will csum IPv6/TCP */ +#define CSUM_SCTP_IPV6 CSUM_IP6_SCTP /* will csum IPv6/SCTP */ + +#define CSUM_IP_CHECKED CSUM_L3_CALC /* did csum IP */ +#define CSUM_IP_VALID CSUM_L3_VALID /* ... the csum is valid */ +#define CSUM_DATA_VALID CSUM_L4_VALID /* csum_data field is valid */ +#define CSUM_SCTP_VALID CSUM_L4_VALID /* SCTP checksum is valid */ +#define CSUM_PSEUDO_HDR 0x00000001 /* XXX csum_data has pseudo hdr */ #define CSUM_DELAY_DATA_IPV6 (CSUM_TCP_IPV6 | CSUM_UDP_IPV6) #define CSUM_DATA_VALID_IPV6 CSUM_DATA_VALID - #define CSUM_DELAY_DATA (CSUM_TCP | CSUM_UDP) -#define CSUM_DELAY_IP (CSUM_IP) /* Only v4, no v6 IP hdr csum */ +#define CSUM_DELAY_IP (CSUM_IP) /* * mbuf types.
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