xref: /freebsd/share/man/man4/virtio_scsi.4 (revision 724b4bfdf1306e4f2c451b6d146fe0fe0353b2c8)
1.\" Copyright (c) 2012 Bryan Venteicher
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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. This tunable disables attempts to issue
61reset bus commands. The default value is 1.
62.El
63.Sh DEBUGGING
64To enable debugging prints from the
65.Nm
66driver, set the
67.Bd -literal -offset indent
68hw.vtscsi.X.debug_level
69.Ed
70.Pp
71variable, where X is the adapter number, either in
72.Xr loader.conf 5
73or via
74.Xr sysctl 8 .
75The following bits have the described effects:
76.Bl -tag -width 6n -offset indent
77.It 0x01
78Enable informational prints.
79.It 0x02
80Enable prints for driver errors.
81.It 0x04
82Enable tracing prints.
83.El
84.Sh SEE ALSO
85.Xr virtio 4
86.Sh HISTORY
87The
88.Nm
89driver was written by
90.An Bryan Venteicher Aq bryanv@daemoninthecloset.org .
91It first appeared in
92.Fx 10.0 .
93