1 /* 2 * linux/include/linux/inet_lro.h 3 * 4 * Large Receive Offload (ipv4 / tcp) 5 * 6 * (C) Copyright IBM Corp. 2007 7 * 8 * Authors: 9 * Jan-Bernd Themann <themann@de.ibm.com> 10 * Christoph Raisch <raisch@de.ibm.com> 11 * 12 * 13 * This program is free software; you can redistribute it and/or modify 14 * it under the terms of the GNU General Public License as published by 15 * the Free Software Foundation; either version 2, or (at your option) 16 * any later version. 17 * 18 * This program is distributed in the hope that it will be useful, 19 * but WITHOUT ANY WARRANTY; without even the implied warranty of 20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 21 * GNU General Public License for more details. 22 * 23 * You should have received a copy of the GNU General Public License 24 * along with this program; if not, write to the Free Software 25 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 26 */ 27 28 #ifndef __INET_LRO_H_ 29 #define __INET_LRO_H_ 30 31 #include <net/ip.h> 32 #include <net/tcp.h> 33 34 /* 35 * LRO statistics 36 */ 37 38 struct net_lro_stats { 39 unsigned long aggregated; 40 unsigned long flushed; 41 unsigned long no_desc; 42 }; 43 44 /* 45 * LRO descriptor for a tcp session 46 */ 47 struct net_lro_desc { 48 struct sk_buff *parent; 49 struct sk_buff *last_skb; 50 struct skb_frag_struct *next_frag; 51 struct iphdr *iph; 52 struct tcphdr *tcph; 53 struct vlan_group *vgrp; 54 __wsum data_csum; 55 __be32 tcp_rcv_tsecr; 56 __be32 tcp_rcv_tsval; 57 __be32 tcp_ack; 58 u32 tcp_next_seq; 59 u32 skb_tot_frags_len; 60 u16 ip_tot_len; 61 u16 tcp_saw_tstamp; /* timestamps enabled */ 62 __be16 tcp_window; 63 u16 vlan_tag; 64 int pkt_aggr_cnt; /* counts aggregated packets */ 65 int vlan_packet; 66 int mss; 67 int active; 68 }; 69 70 /* 71 * Large Receive Offload (LRO) Manager 72 * 73 * Fields must be set by driver 74 */ 75 76 struct net_lro_mgr { 77 struct net_device *dev; 78 struct net_lro_stats stats; 79 80 /* LRO features */ 81 unsigned long features; 82 #define LRO_F_NAPI 1 /* Pass packets to stack via NAPI */ 83 #define LRO_F_EXTRACT_VLAN_ID 2 /* Set flag if VLAN IDs are extracted 84 from received packets and eth protocol 85 is still ETH_P_8021Q */ 86 87 /* 88 * Set for generated SKBs that are not added to 89 * the frag list in fragmented mode 90 */ 91 u32 ip_summed; 92 u32 ip_summed_aggr; /* Set in aggregated SKBs: CHECKSUM_UNNECESSARY 93 * or CHECKSUM_NONE */ 94 95 int max_desc; /* Max number of LRO descriptors */ 96 int max_aggr; /* Max number of LRO packets to be aggregated */ 97 98 int frag_align_pad; /* Padding required to properly align layer 3 99 * headers in generated skb when using frags */ 100 101 struct net_lro_desc *lro_arr; /* Array of LRO descriptors */ 102 103 /* 104 * Optimized driver functions 105 * 106 * get_skb_header: returns tcp and ip header for packet in SKB 107 */ 108 int (*get_skb_header)(struct sk_buff *skb, void **ip_hdr, 109 void **tcpudp_hdr, u64 *hdr_flags, void *priv); 110 111 /* hdr_flags: */ 112 #define LRO_IPV4 1 /* ip_hdr is IPv4 header */ 113 #define LRO_TCP 2 /* tcpudp_hdr is TCP header */ 114 115 /* 116 * get_frag_header: returns mac, tcp and ip header for packet in SKB 117 * 118 * @hdr_flags: Indicate what kind of LRO has to be done 119 * (IPv4/IPv6/TCP/UDP) 120 */ 121 int (*get_frag_header)(struct skb_frag_struct *frag, void **mac_hdr, 122 void **ip_hdr, void **tcpudp_hdr, u64 *hdr_flags, 123 void *priv); 124 }; 125 126 /* 127 * Processes a SKB 128 * 129 * @lro_mgr: LRO manager to use 130 * @skb: SKB to aggregate 131 * @priv: Private data that may be used by driver functions 132 * (for example get_tcp_ip_hdr) 133 */ 134 135 void lro_receive_skb(struct net_lro_mgr *lro_mgr, 136 struct sk_buff *skb, 137 void *priv); 138 139 /* 140 * Processes a SKB with VLAN HW acceleration support 141 */ 142 143 void lro_vlan_hwaccel_receive_skb(struct net_lro_mgr *lro_mgr, 144 struct sk_buff *skb, 145 struct vlan_group *vgrp, 146 u16 vlan_tag, 147 void *priv); 148 149 /* 150 * Processes a fragment list 151 * 152 * This functions aggregate fragments and generate SKBs do pass 153 * the packets to the stack. 154 * 155 * @lro_mgr: LRO manager to use 156 * @frags: Fragment to be processed. Must contain entire header in first 157 * element. 158 * @len: Length of received data 159 * @true_size: Actual size of memory the fragment is consuming 160 * @priv: Private data that may be used by driver functions 161 * (for example get_tcp_ip_hdr) 162 */ 163 164 void lro_receive_frags(struct net_lro_mgr *lro_mgr, 165 struct skb_frag_struct *frags, 166 int len, int true_size, void *priv, __wsum sum); 167 168 void lro_vlan_hwaccel_receive_frags(struct net_lro_mgr *lro_mgr, 169 struct skb_frag_struct *frags, 170 int len, int true_size, 171 struct vlan_group *vgrp, 172 u16 vlan_tag, 173 void *priv, __wsum sum); 174 175 /* 176 * Forward all aggregated SKBs held by lro_mgr to network stack 177 */ 178 179 void lro_flush_all(struct net_lro_mgr *lro_mgr); 180 181 void lro_flush_pkt(struct net_lro_mgr *lro_mgr, 182 struct iphdr *iph, struct tcphdr *tcph); 183 184 #endif 185