xref: /freebsd/sys/dev/virtio/network/virtio_net.h (revision cddbc3b40812213ff00041f79174cac0be360a2a)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * This header is BSD licensed so anyone can use the definitions to implement
5  * compatible drivers/servers.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of IBM nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
20  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
21  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  * $FreeBSD$
31  */
32 
33 #ifndef _VIRTIO_NET_H
34 #define _VIRTIO_NET_H
35 
36 /* The feature bitmap for virtio net */
37 #define VIRTIO_NET_F_CSUM	0x00001 /* Host handles pkts w/ partial csum */
38 #define VIRTIO_NET_F_GUEST_CSUM 0x00002 /* Guest handles pkts w/ partial csum*/
39 #define VIRTIO_NET_F_MAC	0x00020 /* Host has given MAC address. */
40 #define VIRTIO_NET_F_GSO	0x00040 /* Host handles pkts w/ any GSO type */
41 #define VIRTIO_NET_F_GUEST_TSO4	0x00080 /* Guest can handle TSOv4 in. */
42 #define VIRTIO_NET_F_GUEST_TSO6	0x00100 /* Guest can handle TSOv6 in. */
43 #define VIRTIO_NET_F_GUEST_ECN	0x00200 /* Guest can handle TSO[6] w/ ECN in.*/
44 #define VIRTIO_NET_F_GUEST_UFO	0x00400 /* Guest can handle UFO in. */
45 #define VIRTIO_NET_F_HOST_TSO4	0x00800 /* Host can handle TSOv4 in. */
46 #define VIRTIO_NET_F_HOST_TSO6	0x01000 /* Host can handle TSOv6 in. */
47 #define VIRTIO_NET_F_HOST_ECN	0x02000 /* Host can handle TSO[6] w/ ECN in. */
48 #define VIRTIO_NET_F_HOST_UFO	0x04000 /* Host can handle UFO in. */
49 #define VIRTIO_NET_F_MRG_RXBUF	0x08000 /* Host can merge receive buffers. */
50 #define VIRTIO_NET_F_STATUS	0x10000 /* virtio_net_config.status available*/
51 #define VIRTIO_NET_F_CTRL_VQ	0x20000 /* Control channel available */
52 #define VIRTIO_NET_F_CTRL_RX	0x40000 /* Control channel RX mode support */
53 #define VIRTIO_NET_F_CTRL_VLAN	0x80000 /* Control channel VLAN filtering */
54 #define VIRTIO_NET_F_CTRL_RX_EXTRA 0x100000 /* Extra RX mode control support */
55 #define VIRTIO_NET_F_GUEST_ANNOUNCE 0x200000 /* Announce device on network */
56 #define VIRTIO_NET_F_MQ		0x400000 /* Device supports RFS */
57 #define VIRTIO_NET_F_CTRL_MAC_ADDR 0x800000 /* Set MAC address */
58 
59 #define VIRTIO_NET_S_LINK_UP	1	/* Link is up */
60 
61 struct virtio_net_config {
62 	/* The config defining mac address (if VIRTIO_NET_F_MAC) */
63 	uint8_t		mac[ETHER_ADDR_LEN];
64 	/* See VIRTIO_NET_F_STATUS and VIRTIO_NET_S_* above */
65 	uint16_t	status;
66 	/* Maximum number of each of transmit and receive queues;
67 	 * see VIRTIO_NET_F_MQ and VIRTIO_NET_CTRL_MQ.
68 	 * Legal values are between 1 and 0x8000.
69 	 */
70 	uint16_t	max_virtqueue_pairs;
71 } __packed;
72 
73 /*
74  * This is the first element of the scatter-gather list.  If you don't
75  * specify GSO or CSUM features, you can simply ignore the header.
76  */
77 struct virtio_net_hdr {
78 #define VIRTIO_NET_HDR_F_NEEDS_CSUM	1	/* Use csum_start,csum_offset*/
79 #define VIRTIO_NET_HDR_F_DATA_VALID	2	/* Csum is valid */
80 	uint8_t	flags;
81 #define VIRTIO_NET_HDR_GSO_NONE		0	/* Not a GSO frame */
82 #define VIRTIO_NET_HDR_GSO_TCPV4	1	/* GSO frame, IPv4 TCP (TSO) */
83 #define VIRTIO_NET_HDR_GSO_UDP		3	/* GSO frame, IPv4 UDP (UFO) */
84 #define VIRTIO_NET_HDR_GSO_TCPV6	4	/* GSO frame, IPv6 TCP */
85 #define VIRTIO_NET_HDR_GSO_ECN		0x80	/* TCP has ECN set */
86 	uint8_t gso_type;
87 	uint16_t hdr_len;	/* Ethernet + IP + tcp/udp hdrs */
88 	uint16_t gso_size;	/* Bytes to append to hdr_len per frame */
89 	uint16_t csum_start;	/* Position to start checksumming from */
90 	uint16_t csum_offset;	/* Offset after that to place checksum */
91 };
92 
93 /*
94  * This is the version of the header to use when the MRG_RXBUF
95  * feature has been negotiated.
96  */
97 struct virtio_net_hdr_mrg_rxbuf {
98 	struct virtio_net_hdr hdr;
99 	uint16_t num_buffers;	/* Number of merged rx buffers */
100 };
101 
102 /*
103  * Control virtqueue data structures
104  *
105  * The control virtqueue expects a header in the first sg entry
106  * and an ack/status response in the last entry.  Data for the
107  * command goes in between.
108  */
109 struct virtio_net_ctrl_hdr {
110 	uint8_t class;
111 	uint8_t cmd;
112 } __packed;
113 
114 #define VIRTIO_NET_OK	0
115 #define VIRTIO_NET_ERR	1
116 
117 /*
118  * Control the RX mode, ie. promiscuous, allmulti, etc...
119  * All commands require an "out" sg entry containing a 1 byte
120  * state value, zero = disable, non-zero = enable.  Commands
121  * 0 and 1 are supported with the VIRTIO_NET_F_CTRL_RX feature.
122  * Commands 2-5 are added with VIRTIO_NET_F_CTRL_RX_EXTRA.
123  */
124 #define VIRTIO_NET_CTRL_RX	0
125 #define VIRTIO_NET_CTRL_RX_PROMISC	0
126 #define VIRTIO_NET_CTRL_RX_ALLMULTI	1
127 #define VIRTIO_NET_CTRL_RX_ALLUNI	2
128 #define VIRTIO_NET_CTRL_RX_NOMULTI	3
129 #define VIRTIO_NET_CTRL_RX_NOUNI	4
130 #define VIRTIO_NET_CTRL_RX_NOBCAST	5
131 
132 /*
133  * Control the MAC filter table.
134  *
135  * The MAC filter table is managed by the hypervisor, the guest should
136  * assume the size is infinite.  Filtering should be considered
137  * non-perfect, ie. based on hypervisor resources, the guest may
138  * received packets from sources not specified in the filter list.
139  *
140  * In addition to the class/cmd header, the TABLE_SET command requires
141  * two out scatterlists.  Each contains a 4 byte count of entries followed
142  * by a concatenated byte stream of the ETH_ALEN MAC addresses.  The
143  * first sg list contains unicast addresses, the second is for multicast.
144  * This functionality is present if the VIRTIO_NET_F_CTRL_RX feature
145  * is available.
146  *
147  * The ADDR_SET command requests one out scatterlist, it contains a
148  * 6 bytes MAC address. This functionality is present if the
149  * VIRTIO_NET_F_CTRL_MAC_ADDR feature is available.
150  */
151 struct virtio_net_ctrl_mac {
152 	uint32_t	entries;
153 	uint8_t		macs[][ETHER_ADDR_LEN];
154 } __packed;
155 
156 #define VIRTIO_NET_CTRL_MAC	1
157 #define VIRTIO_NET_CTRL_MAC_TABLE_SET	0
158 #define VIRTIO_NET_CTRL_MAC_ADDR_SET	1
159 
160 /*
161  * Control VLAN filtering
162  *
163  * The VLAN filter table is controlled via a simple ADD/DEL interface.
164  * VLAN IDs not added may be filtered by the hypervisor.  Del is the
165  * opposite of add.  Both commands expect an out entry containing a 2
166  * byte VLAN ID.  VLAN filtering is available with the
167  * VIRTIO_NET_F_CTRL_VLAN feature bit.
168  */
169 #define VIRTIO_NET_CTRL_VLAN	2
170 #define VIRTIO_NET_CTRL_VLAN_ADD	0
171 #define VIRTIO_NET_CTRL_VLAN_DEL	1
172 
173 /*
174  * Control link announce acknowledgement
175  *
176  * The command VIRTIO_NET_CTRL_ANNOUNCE_ACK is used to indicate that
177  * driver has recevied the notification; device would clear the
178  * VIRTIO_NET_S_ANNOUNCE bit in the status field after it receives
179  * this command.
180  */
181 #define VIRTIO_NET_CTRL_ANNOUNCE	3
182 #define VIRTIO_NET_CTRL_ANNOUNCE_ACK	0
183 
184 /*
185  * Control Receive Flow Steering
186  *
187  * The command VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET enables Receive Flow
188  * Steering, specifying the number of the transmit and receive queues
189  * that will be used. After the command is consumed and acked by the
190  * device, the device will not steer new packets on receive virtqueues
191  * other than specified nor read from transmit virtqueues other than
192  * specified. Accordingly, driver should not transmit new packets on
193  * virtqueues other than specified.
194  */
195 struct virtio_net_ctrl_mq {
196 	uint16_t	virtqueue_pairs;
197 } __packed;
198 
199 #define VIRTIO_NET_CTRL_MQ	4
200 #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET		0
201 #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN		1
202 #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX		0x8000
203 
204 #endif /* _VIRTIO_NET_H */
205