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virtio_net.h
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1 #ifndef _LINUX_VIRTIO_NET_H
2 #define _LINUX_VIRTIO_NET_H
3 /* This header is BSD licensed so anyone can use the definitions to implement
4  * compatible drivers/servers.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  * notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  * notice, this list of conditions and the following disclaimer in the
13  * documentation and/or other materials provided with the distribution.
14  * 3. Neither the name of IBM nor the names of its contributors
15  * may be used to endorse or promote products derived from this software
16  * without specific prior written permission.
17  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE. */
28 #include <linux/types.h>
29 #include <linux/virtio_ids.h>
30 #include <linux/virtio_config.h>
31 #include <linux/if_ether.h>
32 
33 /* The feature bitmap for virtio net */
34 #define VIRTIO_NET_F_CSUM 0 /* Host handles pkts w/ partial csum */
35 #define VIRTIO_NET_F_GUEST_CSUM 1 /* Guest handles pkts w/ partial csum */
36 #define VIRTIO_NET_F_MAC 5 /* Host has given MAC address. */
37 #define VIRTIO_NET_F_GSO 6 /* Host handles pkts w/ any GSO type */
38 #define VIRTIO_NET_F_GUEST_TSO4 7 /* Guest can handle TSOv4 in. */
39 #define VIRTIO_NET_F_GUEST_TSO6 8 /* Guest can handle TSOv6 in. */
40 #define VIRTIO_NET_F_GUEST_ECN 9 /* Guest can handle TSO[6] w/ ECN in. */
41 #define VIRTIO_NET_F_GUEST_UFO 10 /* Guest can handle UFO in. */
42 #define VIRTIO_NET_F_HOST_TSO4 11 /* Host can handle TSOv4 in. */
43 #define VIRTIO_NET_F_HOST_TSO6 12 /* Host can handle TSOv6 in. */
44 #define VIRTIO_NET_F_HOST_ECN 13 /* Host can handle TSO[6] w/ ECN in. */
45 #define VIRTIO_NET_F_HOST_UFO 14 /* Host can handle UFO in. */
46 #define VIRTIO_NET_F_MRG_RXBUF 15 /* Host can merge receive buffers. */
47 #define VIRTIO_NET_F_STATUS 16 /* virtio_net_config.status available */
48 #define VIRTIO_NET_F_CTRL_VQ 17 /* Control channel available */
49 #define VIRTIO_NET_F_CTRL_RX 18 /* Control channel RX mode support */
50 #define VIRTIO_NET_F_CTRL_VLAN 19 /* Control channel VLAN filtering */
51 #define VIRTIO_NET_F_CTRL_RX_EXTRA 20 /* Extra RX mode control support */
52 #define VIRTIO_NET_F_GUEST_ANNOUNCE 21 /* Guest can announce device on the
53  * network */
54 
55 #define VIRTIO_NET_S_LINK_UP 1 /* Link is up */
56 #define VIRTIO_NET_S_ANNOUNCE 2 /* Announcement is needed */
57 
58 struct virtio_net_config {
59  /* The config defining mac address (if VIRTIO_NET_F_MAC) */
60  __u8 mac[6];
61  /* See VIRTIO_NET_F_STATUS and VIRTIO_NET_S_* above */
62  __u16 status;
63 } __attribute__((packed));
64 
65 /* This is the first element of the scatter-gather list. If you don't
66  * specify GSO or CSUM features, you can simply ignore the header. */
68 #define VIRTIO_NET_HDR_F_NEEDS_CSUM 1 // Use csum_start, csum_offset
69 #define VIRTIO_NET_HDR_F_DATA_VALID 2 // Csum is valid
71 #define VIRTIO_NET_HDR_GSO_NONE 0 // Not a GSO frame
72 #define VIRTIO_NET_HDR_GSO_TCPV4 1 // GSO frame, IPv4 TCP (TSO)
73 #define VIRTIO_NET_HDR_GSO_UDP 3 // GSO frame, IPv4 UDP (UFO)
74 #define VIRTIO_NET_HDR_GSO_TCPV6 4 // GSO frame, IPv6 TCP
75 #define VIRTIO_NET_HDR_GSO_ECN 0x80 // TCP has ECN set
77  __u16 hdr_len; /* Ethernet + IP + tcp/udp hdrs */
78  __u16 gso_size; /* Bytes to append to hdr_len per frame */
79  __u16 csum_start; /* Position to start checksumming from */
80  __u16 csum_offset; /* Offset after that to place checksum */
81 };
82 
83 /* This is the version of the header to use when the MRG_RXBUF
84  * feature has been negotiated. */
87  __u16 num_buffers; /* Number of merged rx buffers */
88 };
89 
90 /*
91  * Control virtqueue data structures
92  *
93  * The control virtqueue expects a header in the first sg entry
94  * and an ack/status response in the last entry. Data for the
95  * command goes in between.
96  */
98  __u8 class;
99  __u8 cmd;
100 } __attribute__((packed));
102 typedef __u8 virtio_net_ctrl_ack;
104 #define VIRTIO_NET_OK 0
105 #define VIRTIO_NET_ERR 1
106 
107 /*
108  * Control the RX mode, ie. promisucous, allmulti, etc...
109  * All commands require an "out" sg entry containing a 1 byte
110  * state value, zero = disable, non-zero = enable. Commands
111  * 0 and 1 are supported with the VIRTIO_NET_F_CTRL_RX feature.
112  * Commands 2-5 are added with VIRTIO_NET_F_CTRL_RX_EXTRA.
113  */
114 #define VIRTIO_NET_CTRL_RX 0
115  #define VIRTIO_NET_CTRL_RX_PROMISC 0
116  #define VIRTIO_NET_CTRL_RX_ALLMULTI 1
117  #define VIRTIO_NET_CTRL_RX_ALLUNI 2
118  #define VIRTIO_NET_CTRL_RX_NOMULTI 3
119  #define VIRTIO_NET_CTRL_RX_NOUNI 4
120  #define VIRTIO_NET_CTRL_RX_NOBCAST 5
121 
122 /*
123  * Control the MAC filter table.
124  *
125  * The MAC filter table is managed by the hypervisor, the guest should
126  * assume the size is infinite. Filtering should be considered
127  * non-perfect, ie. based on hypervisor resources, the guest may
128  * received packets from sources not specified in the filter list.
129  *
130  * In addition to the class/cmd header, the TABLE_SET command requires
131  * two out scatterlists. Each contains a 4 byte count of entries followed
132  * by a concatenated byte stream of the ETH_ALEN MAC addresses. The
133  * first sg list contains unicast addresses, the second is for multicast.
134  * This functionality is present if the VIRTIO_NET_F_CTRL_RX feature
135  * is available.
136  */
139  __u8 macs[][ETH_ALEN];
140 } __attribute__((packed));
142 #define VIRTIO_NET_CTRL_MAC 1
143  #define VIRTIO_NET_CTRL_MAC_TABLE_SET 0
144 
145 /*
146  * Control VLAN filtering
147  *
148  * The VLAN filter table is controlled via a simple ADD/DEL interface.
149  * VLAN IDs not added may be filterd by the hypervisor. Del is the
150  * opposite of add. Both commands expect an out entry containing a 2
151  * byte VLAN ID. VLAN filterting is available with the
152  * VIRTIO_NET_F_CTRL_VLAN feature bit.
153  */
154 #define VIRTIO_NET_CTRL_VLAN 2
155  #define VIRTIO_NET_CTRL_VLAN_ADD 0
156  #define VIRTIO_NET_CTRL_VLAN_DEL 1
157 
158 /*
159  * Control link announce acknowledgement
160  *
161  * The command VIRTIO_NET_CTRL_ANNOUNCE_ACK is used to indicate that
162  * driver has recevied the notification; device would clear the
163  * VIRTIO_NET_S_ANNOUNCE bit in the status field after it receives
164  * this command.
165  */
166 #define VIRTIO_NET_CTRL_ANNOUNCE 3
167  #define VIRTIO_NET_CTRL_ANNOUNCE_ACK 0
168 
169 #endif /* _LINUX_VIRTIO_NET_H */