/* * linux/include/linux/inet_lro.h * * Large Receive Offload (ipv4 / tcp) * * (C) Copyright IBM Corp. 2007 * * Authors: * Jan-Bernd Themann <themann@de.ibm.com> * Christoph Raisch <raisch@de.ibm.com> * * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #ifndef __INET_LRO_H_ #define __INET_LRO_H_ #include <net/ip.h> #include <net/tcp.h> /* * LRO statistics */ struct net_lro_stats { unsigned long aggregated; unsigned long flushed; unsigned long no_desc; }; /* * LRO descriptor for a tcp session */ struct net_lro_desc { struct sk_buff *parent; struct sk_buff *last_skb; struct skb_frag_struct *next_frag; struct iphdr *iph; struct tcphdr *tcph; __wsum data_csum; __be32 tcp_rcv_tsecr; __be32 tcp_rcv_tsval; __be32 tcp_ack; u32 tcp_next_seq; u32 skb_tot_frags_len; u16 ip_tot_len; u16 tcp_saw_tstamp; /* timestamps enabled */ __be16 tcp_window; int pkt_aggr_cnt; /* counts aggregated packets */ int vlan_packet; int mss; int active; }; /* * Large Receive Offload (LRO) Manager * * Fields must be set by driver */ struct net_lro_mgr { struct net_device *dev; struct net_lro_stats stats; /* LRO features */ unsigned long features; #define LRO_F_NAPI 1 /* Pass packets to stack via NAPI */ #define LRO_F_EXTRACT_VLAN_ID 2 /* Set flag if VLAN IDs are extracted from received packets and eth protocol is still ETH_P_8021Q */ /* * Set for generated SKBs that are not added to * the frag list in fragmented mode */ u32 ip_summed; u32 ip_summed_aggr; /* Set in aggregated SKBs: CHECKSUM_UNNECESSARY * or CHECKSUM_NONE */ int max_desc; /* Max number of LRO descriptors */ int max_aggr; /* Max number of LRO packets to be aggregated */ int frag_align_pad; /* Padding required to properly align layer 3 * headers in generated skb when using frags */ struct net_lro_desc *lro_arr; /* Array of LRO descriptors */ /* * Optimized driver functions * * get_skb_header: returns tcp and ip header for packet in SKB */ int (*get_skb_header)(struct sk_buff *skb, void **ip_hdr, void **tcpudp_hdr, u64 *hdr_flags, void *priv); /* hdr_flags: */ #define LRO_IPV4 1 /* ip_hdr is IPv4 header */ #define LRO_TCP 2 /* tcpudp_hdr is TCP header */ /* * get_frag_header: returns mac, tcp and ip header for packet in SKB * * @hdr_flags: Indicate what kind of LRO has to be done * (IPv4/IPv6/TCP/UDP) */ int (*get_frag_header)(struct skb_frag_struct *frag, void **mac_hdr, void **ip_hdr, void **tcpudp_hdr, u64 *hdr_flags, void *priv); }; /* * Processes a SKB * * @lro_mgr: LRO manager to use * @skb: SKB to aggregate * @priv: Private data that may be used by driver functions * (for example get_tcp_ip_hdr) */ void lro_receive_skb(struct net_lro_mgr *lro_mgr, struct sk_buff *skb, void *priv); /* * Processes a fragment list * * This functions aggregate fragments and generate SKBs do pass * the packets to the stack. * * @lro_mgr: LRO manager to use * @frags: Fragment to be processed. Must contain entire header in first * element. * @len: Length of received data * @true_size: Actual size of memory the fragment is consuming * @priv: Private data that may be used by driver functions * (for example get_tcp_ip_hdr) */ void lro_receive_frags(struct net_lro_mgr *lro_mgr, struct skb_frag_struct *frags, int len, int true_size, void *priv, __wsum sum); /* * Forward all aggregated SKBs held by lro_mgr to network stack */ void lro_flush_all(struct net_lro_mgr *lro_mgr); void lro_flush_pkt(struct net_lro_mgr *lro_mgr, struct iphdr *iph, struct tcphdr *tcph); #endif