xref: /freebsd/usr.sbin/bhyve/virtio.h (revision 595e514d0df2bac5b813d35f83e32875dbf16a83)
1 /*-
2  * Copyright (c) 2011 NetApp, Inc.
3  * All rights reserved.
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  *
14  * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #ifndef	_VIRTIO_H_
30 #define	_VIRTIO_H_
31 
32 #define VRING_ALIGN	4096
33 
34 #define VRING_DESC_F_NEXT	(1 << 0)
35 #define VRING_DESC_F_WRITE	(1 << 1)
36 #define VRING_DESC_F_INDIRECT	(1 << 2)
37 
38 #define VRING_AVAIL_F_NO_INTERRUPT   1
39 #define VIRTIO_MSI_NO_VECTOR	0xFFFF
40 
41 struct virtio_desc {
42 	uint64_t	vd_addr;
43 	uint32_t	vd_len;
44 	uint16_t	vd_flags;
45 	uint16_t	vd_next;
46 } __packed;
47 
48 struct virtio_used {
49 	uint32_t	vu_idx;
50 	uint32_t	vu_tlen;
51 } __packed;
52 
53 /*
54  * PFN register shift amount
55  */
56 #define VRING_PFN		12
57 
58 /*
59  * Virtio device types
60  */
61 #define VIRTIO_TYPE_NET		1
62 #define VIRTIO_TYPE_BLOCK	2
63 
64 /*
65  * PCI vendor/device IDs
66  */
67 #define VIRTIO_VENDOR		0x1AF4
68 #define VIRTIO_DEV_NET		0x1000
69 #define VIRTIO_DEV_BLOCK	0x1001
70 
71 /*
72  * PCI config space constants
73  */
74 #define VTCFG_R_HOSTCAP		0
75 #define VTCFG_R_GUESTCAP	4
76 #define VTCFG_R_PFN		8
77 #define VTCFG_R_QNUM		12
78 #define VTCFG_R_QSEL		14
79 #define VTCFG_R_QNOTIFY		16
80 #define VTCFG_R_STATUS		18
81 #define VTCFG_R_ISR		19
82 #define VTCFG_R_CFGVEC		20
83 #define VTCFG_R_QVEC		22
84 #define VTCFG_R_CFG0		20	/* No MSI-X */
85 #define VTCFG_R_CFG1		24	/* With MSI-X */
86 #define VTCFG_R_MSIX		20
87 
88 /* Feature flags */
89 #define	VIRTIO_F_NOTIFY_ON_EMPTY	(1 << 24)
90 
91 /* From section 2.3, "Virtqueue Configuration", of the virtio specification */
92 static inline u_int
93 vring_size(u_int qsz)
94 {
95 	u_int size;
96 
97 	size = sizeof(struct virtio_desc) * qsz + sizeof(uint16_t) * (3 + qsz);
98 	size = roundup2(size, VRING_ALIGN);
99 
100 	size += sizeof(uint16_t) * 3 + sizeof(struct virtio_used) * qsz;
101 	size = roundup2(size, VRING_ALIGN);
102 
103 	return (size);
104 }
105 
106 #endif	/* _VIRTIO_H_ */
107