xref: /freebsd/sys/dev/virtio/network/virtio_net.h (revision d6b92ffa)
1 /*-
2  * This header is BSD licensed so anyone can use the definitions to implement
3  * compatible drivers/servers.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of IBM nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  */
30 
31 #ifndef _VIRTIO_NET_H
32 #define _VIRTIO_NET_H
33 
34 /* The feature bitmap for virtio net */
35 #define VIRTIO_NET_F_CSUM	0x00001 /* Host handles pkts w/ partial csum */
36 #define VIRTIO_NET_F_GUEST_CSUM 0x00002 /* Guest handles pkts w/ partial csum*/
37 #define VIRTIO_NET_F_MAC	0x00020 /* Host has given MAC address. */
38 #define VIRTIO_NET_F_GSO	0x00040 /* Host handles pkts w/ any GSO type */
39 #define VIRTIO_NET_F_GUEST_TSO4	0x00080 /* Guest can handle TSOv4 in. */
40 #define VIRTIO_NET_F_GUEST_TSO6	0x00100 /* Guest can handle TSOv6 in. */
41 #define VIRTIO_NET_F_GUEST_ECN	0x00200 /* Guest can handle TSO[6] w/ ECN in.*/
42 #define VIRTIO_NET_F_GUEST_UFO	0x00400 /* Guest can handle UFO in. */
43 #define VIRTIO_NET_F_HOST_TSO4	0x00800 /* Host can handle TSOv4 in. */
44 #define VIRTIO_NET_F_HOST_TSO6	0x01000 /* Host can handle TSOv6 in. */
45 #define VIRTIO_NET_F_HOST_ECN	0x02000 /* Host can handle TSO[6] w/ ECN in. */
46 #define VIRTIO_NET_F_HOST_UFO	0x04000 /* Host can handle UFO in. */
47 #define VIRTIO_NET_F_MRG_RXBUF	0x08000 /* Host can merge receive buffers. */
48 #define VIRTIO_NET_F_STATUS	0x10000 /* virtio_net_config.status available*/
49 #define VIRTIO_NET_F_CTRL_VQ	0x20000 /* Control channel available */
50 #define VIRTIO_NET_F_CTRL_RX	0x40000 /* Control channel RX mode support */
51 #define VIRTIO_NET_F_CTRL_VLAN	0x80000 /* Control channel VLAN filtering */
52 #define VIRTIO_NET_F_CTRL_RX_EXTRA 0x100000 /* Extra RX mode control support */
53 #define VIRTIO_NET_F_GUEST_ANNOUNCE 0x200000 /* Announce device on network */
54 #define VIRTIO_NET_F_MQ		0x400000 /* Device supports RFS */
55 #define VIRTIO_NET_F_CTRL_MAC_ADDR 0x800000 /* Set MAC address */
56 
57 #define VIRTIO_NET_S_LINK_UP	1	/* Link is up */
58 
59 struct virtio_net_config {
60 	/* The config defining mac address (if VIRTIO_NET_F_MAC) */
61 	uint8_t		mac[ETHER_ADDR_LEN];
62 	/* See VIRTIO_NET_F_STATUS and VIRTIO_NET_S_* above */
63 	uint16_t	status;
64 	/* Maximum number of each of transmit and receive queues;
65 	 * see VIRTIO_NET_F_MQ and VIRTIO_NET_CTRL_MQ.
66 	 * Legal values are between 1 and 0x8000.
67 	 */
68 	uint16_t	max_virtqueue_pairs;
69 } __packed;
70 
71 /*
72  * This is the first element of the scatter-gather list.  If you don't
73  * specify GSO or CSUM features, you can simply ignore the header.
74  */
75 struct virtio_net_hdr {
76 #define VIRTIO_NET_HDR_F_NEEDS_CSUM	1	/* Use csum_start,csum_offset*/
77 #define VIRTIO_NET_HDR_F_DATA_VALID	2	/* Csum is valid */
78 	uint8_t	flags;
79 #define VIRTIO_NET_HDR_GSO_NONE		0	/* Not a GSO frame */
80 #define VIRTIO_NET_HDR_GSO_TCPV4	1	/* GSO frame, IPv4 TCP (TSO) */
81 #define VIRTIO_NET_HDR_GSO_UDP		3	/* GSO frame, IPv4 UDP (UFO) */
82 #define VIRTIO_NET_HDR_GSO_TCPV6	4	/* GSO frame, IPv6 TCP */
83 #define VIRTIO_NET_HDR_GSO_ECN		0x80	/* TCP has ECN set */
84 	uint8_t gso_type;
85 	uint16_t hdr_len;	/* Ethernet + IP + tcp/udp hdrs */
86 	uint16_t gso_size;	/* Bytes to append to hdr_len per frame */
87 	uint16_t csum_start;	/* Position to start checksumming from */
88 	uint16_t csum_offset;	/* Offset after that to place checksum */
89 };
90 
91 /*
92  * This is the version of the header to use when the MRG_RXBUF
93  * feature has been negotiated.
94  */
95 struct virtio_net_hdr_mrg_rxbuf {
96 	struct virtio_net_hdr hdr;
97 	uint16_t num_buffers;	/* Number of merged rx buffers */
98 };
99 
100 /*
101  * Control virtqueue data structures
102  *
103  * The control virtqueue expects a header in the first sg entry
104  * and an ack/status response in the last entry.  Data for the
105  * command goes in between.
106  */
107 struct virtio_net_ctrl_hdr {
108 	uint8_t class;
109 	uint8_t cmd;
110 } __packed;
111 
112 #define VIRTIO_NET_OK	0
113 #define VIRTIO_NET_ERR	1
114 
115 /*
116  * Control the RX mode, ie. promiscuous, allmulti, etc...
117  * All commands require an "out" sg entry containing a 1 byte
118  * state value, zero = disable, non-zero = enable.  Commands
119  * 0 and 1 are supported with the VIRTIO_NET_F_CTRL_RX feature.
120  * Commands 2-5 are added with VIRTIO_NET_F_CTRL_RX_EXTRA.
121  */
122 #define VIRTIO_NET_CTRL_RX	0
123 #define VIRTIO_NET_CTRL_RX_PROMISC	0
124 #define VIRTIO_NET_CTRL_RX_ALLMULTI	1
125 #define VIRTIO_NET_CTRL_RX_ALLUNI	2
126 #define VIRTIO_NET_CTRL_RX_NOMULTI	3
127 #define VIRTIO_NET_CTRL_RX_NOUNI	4
128 #define VIRTIO_NET_CTRL_RX_NOBCAST	5
129 
130 /*
131  * Control the MAC filter table.
132  *
133  * The MAC filter table is managed by the hypervisor, the guest should
134  * assume the size is infinite.  Filtering should be considered
135  * non-perfect, ie. based on hypervisor resources, the guest may
136  * received packets from sources not specified in the filter list.
137  *
138  * In addition to the class/cmd header, the TABLE_SET command requires
139  * two out scatterlists.  Each contains a 4 byte count of entries followed
140  * by a concatenated byte stream of the ETH_ALEN MAC addresses.  The
141  * first sg list contains unicast addresses, the second is for multicast.
142  * This functionality is present if the VIRTIO_NET_F_CTRL_RX feature
143  * is available.
144  *
145  * The ADDR_SET command requests one out scatterlist, it contains a
146  * 6 bytes MAC address. This functionality is present if the
147  * VIRTIO_NET_F_CTRL_MAC_ADDR feature is available.
148  */
149 struct virtio_net_ctrl_mac {
150 	uint32_t	entries;
151 	uint8_t		macs[][ETHER_ADDR_LEN];
152 } __packed;
153 
154 #define VIRTIO_NET_CTRL_MAC	1
155 #define VIRTIO_NET_CTRL_MAC_TABLE_SET	0
156 #define VIRTIO_NET_CTRL_MAC_ADDR_SET	1
157 
158 /*
159  * Control VLAN filtering
160  *
161  * The VLAN filter table is controlled via a simple ADD/DEL interface.
162  * VLAN IDs not added may be filtered by the hypervisor.  Del is the
163  * opposite of add.  Both commands expect an out entry containing a 2
164  * byte VLAN ID.  VLAN filtering is available with the
165  * VIRTIO_NET_F_CTRL_VLAN feature bit.
166  */
167 #define VIRTIO_NET_CTRL_VLAN	2
168 #define VIRTIO_NET_CTRL_VLAN_ADD	0
169 #define VIRTIO_NET_CTRL_VLAN_DEL	1
170 
171 /*
172  * Control link announce acknowledgement
173  *
174  * The command VIRTIO_NET_CTRL_ANNOUNCE_ACK is used to indicate that
175  * driver has recevied the notification; device would clear the
176  * VIRTIO_NET_S_ANNOUNCE bit in the status field after it receives
177  * this command.
178  */
179 #define VIRTIO_NET_CTRL_ANNOUNCE	3
180 #define VIRTIO_NET_CTRL_ANNOUNCE_ACK	0
181 
182 /*
183  * Control Receive Flow Steering
184  *
185  * The command VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET enables Receive Flow
186  * Steering, specifying the number of the transmit and receive queues
187  * that will be used. After the command is consumed and acked by the
188  * device, the device will not steer new packets on receive virtqueues
189  * other than specified nor read from transmit virtqueues other than
190  * specified. Accordingly, driver should not transmit new packets on
191  * virtqueues other than specified.
192  */
193 struct virtio_net_ctrl_mq {
194 	uint16_t	virtqueue_pairs;
195 } __packed;
196 
197 #define VIRTIO_NET_CTRL_MQ	4
198 #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET		0
199 #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN		1
200 #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX		0x8000
201 
202 #endif /* _VIRTIO_NET_H */
203