xref: /freebsd/share/man/man4/virtio_scsi.4 (revision a0409676120c1e558d0ade943019934e0f15118d)
1.\" Copyright (c) 2012 Bryan Venteicher
2.\" All rights reserved.
3.\"
4.\" Redistribution and use in source and binary forms, with or without
5.\" modification, are permitted provided that the following conditions
6.\" are met:
7.\" 1. Redistributions of source code must retain the above copyright
8.\"    notice, this list of conditions and the following disclaimer.
9.\" 2. Redistributions in binary form must reproduce the above copyright
10.\"    notice, this list of conditions and the following disclaimer in the
11.\"    documentation and/or other materials provided with the distribution.
12.\"
13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23.\" SUCH DAMAGE.
24.\"
25.\" $FreeBSD$
26.\"
27.Dd June 24, 2012
28.Dt VIRTIO_SCSI 4
29.Os
30.Sh NAME
31.Nm virtio_scsi
32.Nd VirtIO SCSI driver
33.Sh SYNOPSIS
34To compile this driver into the kernel,
35place the following lines in your
36kernel configuration file:
37.Bd -ragged -offset indent
38.Cd "device virtio_scsi"
39.Ed
40.Pp
41Alternatively, to load the driver as a
42module at boot time, place the following line in
43.Xr loader.conf 5 :
44.Bd -literal -offset indent
45virtio_scsi_load="YES"
46.Ed
47.Sh DESCRIPTION
48The
49.Nm
50device driver provides support for VirtIO SCSI devices.
51.Sh LOADER TUNABLES
52Tunables can be set at the
53.Xr loader 8
54prompt before booting the kernel or stored in
55.Xr loader.conf 5 .
56.Bl -tag -width "xxxxxx"
57.It Va hw.vtscsi.bus_reset_disable
58In the initial QEMU release with VirtIO SCSI support, in-flight
59operations were not aborted when stopping the device, rendering
60bus reset ineffective.
61This tunable disables attempts to issue reset bus commands.
62The default value is 1.
63.El
64.Sh DEBUGGING
65To enable debugging prints from the
66.Nm
67driver, set the
68.Bd -literal -offset indent
69hw.vtscsi.X.debug_level
70.Ed
71.Pp
72variable, where X is the adapter number, either in
73.Xr loader.conf 5
74or via
75.Xr sysctl 8 .
76The following bits have the described effects:
77.Bl -tag -width 6n -offset indent
78.It 0x01
79Enable informational prints.
80.It 0x02
81Enable prints for driver errors.
82.It 0x04
83Enable tracing prints.
84.El
85.Sh SEE ALSO
86.Xr virtio 4
87.Sh HISTORY
88The
89.Nm
90driver was written by
91.An Bryan Venteicher Aq Mt bryanv@FreeBSD.org .
92It first appeared in
93.Fx 10.0 .
94