summaryrefslogtreecommitdiff
path: root/include/linux/inet_lro.h
blob: 1246d46abbc089c6a87322b46fe6b03bde1f0189 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
/*
 *  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;
	struct vlan_group *vgrp;
	__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;
	u16 vlan_tag;
	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 */

	u32 ip_summed;      /* Set in non generated SKBs in page mode */
	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 */

	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 SKB with VLAN HW acceleration support
 */

void lro_vlan_hwaccel_receive_skb(struct net_lro_mgr *lro_mgr,
				  struct sk_buff *skb,
				  struct vlan_group *vgrp,
				  u16 vlan_tag,
				  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);

void lro_vlan_hwaccel_receive_frags(struct net_lro_mgr *lro_mgr,
				    struct skb_frag_struct *frags,
				    int len, int true_size,
				    struct vlan_group *vgrp,
				    u16 vlan_tag,
				    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