116 lines
3.9 KiB
Groff
116 lines
3.9 KiB
Groff
.\" Copyright (c) 2011 Bryan Venteicher
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd January 22, 2012
|
|
.Dt VTNET 4
|
|
.Os
|
|
.Sh NAME
|
|
.Nm vtnet
|
|
.Nd VirtIO Ethernet driver
|
|
.Sh SYNOPSIS
|
|
To compile this driver into the kernel,
|
|
place the following lines in your
|
|
kernel configuration file:
|
|
.Bd -ragged -offset indent
|
|
.Cd "device vtnet"
|
|
.Ed
|
|
.Pp
|
|
Alternatively, to load the driver as a
|
|
module at boot time, place the following line in
|
|
.Xr loader.conf 5 :
|
|
.Bd -literal -offset indent
|
|
if_vtnet_load="YES"
|
|
.Ed
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm
|
|
device driver provides support for VirtIO Ethernet devices.
|
|
.Pp
|
|
If the hypervisor advertises the appreciate features, the
|
|
.Nm
|
|
driver supports TCP/UDP checksum offload for both transmit and receive,
|
|
TCP segmentation offload (TSO), TCP large receive offload (LRO), and
|
|
hardware VLAN tag stripping/insertion features, as well as a multicast
|
|
hash filter, as well as Jumbo Frames (up to 9216 bytes), which can be
|
|
configured via the interface MTU setting.
|
|
Selecting an MTU larger than 1500 bytes with the
|
|
.Xr ifconfig 8
|
|
utility configures the adapter to receive and transmit Jumbo Frames.
|
|
.Pp
|
|
For more information on configuring this device, see
|
|
.Xr ifconfig 8 .
|
|
.Sh LOADER TUNABLES
|
|
Tunables can be set at the
|
|
.Xr loader 8
|
|
prompt before booting the kernel or stored in
|
|
.Xr loader.conf 5 .
|
|
.Bl -tag -width "xxxxxx"
|
|
.It Va hw.vtnet.csum_disable
|
|
.It Va hw.vtnet. Ns Ar X Ns Va .csum_disable
|
|
This tunable disables receive and send checksum offload.
|
|
The default value is 0.
|
|
.It Va hw.vtnet.tso_disable
|
|
.It Va hw.vtnet. Ns Ar X Ns Va .tso_disable
|
|
This tunable disables TSO.
|
|
The default value is 0.
|
|
.It Va hw.vtnet.lro_disable
|
|
.It Va hw.vtnet. Ns Ar X Ns Va .lro_disable
|
|
This tunable disables LRO.
|
|
The default value is 0.
|
|
.It Va hw.vtnet.mq_disable
|
|
.It Va hw.vtnet. Ns Ar X Ns Va .mq_disable
|
|
This tunable disables multiqueue.
|
|
The default value is 0.
|
|
.It Va hw.vtnet.mq_max_pairs
|
|
.It Va hw.vtnet. Ns Ar X Ns Va .mq_max_pairs
|
|
This tunable sets the maximum number of transmit and receive queue pairs.
|
|
Multiple queues are only supported when the Multiqueue feature is negotiated.
|
|
This driver supports a maximum of 8 queue pairs.
|
|
The number of queue pairs used is the lesser of the maximum supported by the
|
|
driver and the hypervisor, the number of CPUs present in the guest, and this
|
|
tunable if not zero.
|
|
The default value is 0.
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr arp 4 ,
|
|
.Xr netintro 4 ,
|
|
.Xr ng_ether 4 ,
|
|
.Xr virtio 4 ,
|
|
.Xr vlan 4 ,
|
|
.Xr ifconfig 8
|
|
.Sh HISTORY
|
|
The
|
|
.Nm
|
|
driver was written by
|
|
.An Bryan Venteicher Aq Mt bryanv@FreeBSD.org .
|
|
It first appeared in
|
|
.Fx 9.0 .
|
|
.Sh CAVEATS
|
|
The
|
|
.Nm
|
|
driver only supports LRO when the hypervisor advertises the
|
|
mergeable buffer feature.
|