xref: /dragonfly/share/man/man4/virtio_scsi.4 (revision ed36d35d)
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25.\" $FreeBSD: head/share/man/man4/virtio_scsi.4 301589 2016-06-08 08:50:35Z trasz $
26.\"
27.Dd July 30, 2017
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