.\"	$NetBSD: virtio.4,v 1.9 2018/06/07 12:32:26 jakllsch Exp $
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.Dd June 7, 2018
.Dt VIRTIO 4
.Os
.Sh NAME
.Nm virtio
.Nd Para-virtualized I/O in a virtual machine
.Sh SYNOPSIS
.Cd "virtio* at fdt?"
.Cd "virtio* at pci? dev ? function ?"
.Cd "ld* at virtio?"
.Cd "vioif* at virtio?"
.Cd "viomb* at virtio?"
.Cd "viornd* at virtio?"
.Cd "vioscsi* at virtio?"
.Sh DESCRIPTION
.Nm
defines an interface for efficient, standard and extensible I/O between the
hypervisor and the virtual machine.
The
.Nm
device driver represents an emulated device that the hypervisor makes
available to the virtual machine.
.Pp
.Nm
driver itself provides the core infrastructure to communicate
with the hypervisor (called virtqueues) and supports the following devices:
.Bl -tag -width xxxxx
.It Xr ld 4
A Disk device.
.It Xr vioif 4
An Ethernet device.
.It Xr viomb 4
A pseudo-device to release memory back to the hypervisor.
.It Xr viornd 4
An entropy source.
.It Xr vioscsi 4
A SCSI adapter.
.El
.Sh SEE ALSO
.Xr ld 4 ,
.Xr pci 4 ,
.Xr vioif 4 ,
.Xr viomb 4 ,
.Xr viornd 4 ,
.Xr vioscsi 4
.Pp
.Rs
.%A Rusty Russell, IBM Corporation
.%T Virtio PCI Card Specification
.%U http://ozlabs.org/~rusty/virtio-spec/
.Re
.Sh HISTORY
The
.Nm
driver first appeared in
.Nx 6.0 .