1.\" $OpenBSD: virtio.4,v 1.17 2023/04/26 22:34:30 jmc Exp $ 2.\" 3.\" Copyright (c) 2012 Stefan Fritsch <sf@sfritsch.de> 4.\" 5.\" Permission to use, copy, modify, and distribute this software for any 6.\" purpose with or without fee is hereby granted, provided that the above 7.\" copyright notice and this permission notice appear in all copies. 8.\" 9.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16.\" 17.Dd $Mdocdate: April 26 2023 $ 18.Dt VIRTIO 4 19.Os 20.Sh NAME 21.Nm virtio 22.Nd VirtIO support driver 23.Sh SYNOPSIS 24.Cd "virtio* at fdt?" 25.Cd "virtio* at pci? flags 0x00" 26.Sh DESCRIPTION 27The 28.Nm 29driver provides support service for paravirtualized devices using the VirtIO 30protocol. 31Such devices are provided by bhyve, KVM, QEMU, VirtualBox, and 32.Xr vmm 4 . 33.Pp 34Currently there are drivers for the following 35.Nm 36devices: 37.Pp 38.Bl -tag -width "vioscsi(4)XXX" -offset indent -compact 39.It Xr vio 4 40VirtIO network device 41.It Xr vioblk 4 42VirtIO disk 43.It Xr viocon 4 44VirtIO console device 45.It Xr viogpu 4 46VirtIO GPU device 47.It Xr viomb 4 48VirtIO memory ballooning driver 49.It Xr viornd 4 50VirtIO random number device 51.It Xr vioscsi 4 52VirtIO SCSI adapter 53.It Xr vmmci 4 54.Xr vmm 4 55control interface 56.El 57.Pp 58The 59.Nm 60driver conforms to the virtio 0.9.5 specification. 61The virtio 1.0 standard is only supported for PCI devices. 62.Pp 63By default 0.9 is preferred over 1.0. 64This can be changed by setting the bit 0x4 in the flags. 65Setting the bit 0x8 in the flags disables 1.0 support completely. 66.Sh SEE ALSO 67.Xr intro 4 68.Sh HISTORY 69The 70.Nm 71driver first appeared in 72.Ox 5.3 . 73.Sh AUTHORS 74.An -nosplit 75The 76.Nm 77driver was ported to 78.Ox 79and improved by 80.An Stefan Fritsch Aq Mt sf@sfritsch.de . 81It is based on the 82.Nx 83driver by 84.An Minoura Makoto . 85.Sh BUGS 86.Nm 87big-endian architectures are not yet supported. 88