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Jan-Bernd Themann71c87e02007-08-08 22:38:05 -07001/*
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
38struct 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 */
47struct 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;
Al Viro9df7c982007-10-14 19:40:59 +010055 __be32 tcp_rcv_tsecr;
56 __be32 tcp_rcv_tsval;
Al Virof53f4132007-10-14 19:41:09 +010057 __be32 tcp_ack;
Jan-Bernd Themann71c87e02007-08-08 22:38:05 -070058 u32 tcp_next_seq;
59 u32 skb_tot_frags_len;
60 u16 ip_tot_len;
61 u16 tcp_saw_tstamp; /* timestamps enabled */
Al Viro9df7c982007-10-14 19:40:59 +010062 __be16 tcp_window;
Jan-Bernd Themann71c87e02007-08-08 22:38:05 -070063 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
76struct 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
Eli Cohen251a4b32008-06-27 20:09:00 -070087 /*
88 * Set for generated SKBs that are not added to
89 * the frag list in fragmented mode
90 */
91 u32 ip_summed;
Jan-Bernd Themann71c87e02007-08-08 22:38:05 -070092 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
Andrew Gallatin621544e2007-12-05 02:31:42 -080098 int frag_align_pad; /* Padding required to properly align layer 3
99 * headers in generated skb when using frags */
100
Jan-Bernd Themann71c87e02007-08-08 22:38:05 -0700101 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
135void 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
143void 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
164void 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
168void 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
179void lro_flush_all(struct net_lro_mgr *lro_mgr);
180
181void lro_flush_pkt(struct net_lro_mgr *lro_mgr,
182 struct iphdr *iph, struct tcphdr *tcph);
183
184#endif