xref: /freebsd/share/man/man4/virtio_scsi.4 (revision a64729f5077d77e13b9497cb33ecb3c82e606ee8)
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25.Dd June 24, 2012
26.Dt VIRTIO_SCSI 4
27.Os
28.Sh NAME
29.Nm virtio_scsi
30.Nd VirtIO SCSI driver
31.Sh SYNOPSIS
32To compile this driver into the kernel,
33place the following lines in your
34kernel configuration file:
35.Bd -ragged -offset indent
36.Cd "device virtio_scsi"
37.Ed
38.Pp
39Alternatively, to load the driver as a
40module at boot time, place the following line in
41.Xr loader.conf 5 :
42.Bd -literal -offset indent
43virtio_scsi_load="YES"
44.Ed
45.Sh DESCRIPTION
46The
47.Nm
48device driver provides support for VirtIO SCSI devices.
49.Sh LOADER TUNABLES
50Tunables can be set at the
51.Xr loader 8
52prompt before booting the kernel or stored in
53.Xr loader.conf 5 .
54.Bl -tag -width "xxxxxx"
55.It Va hw.vtscsi.bus_reset_disable
56In the initial QEMU release with VirtIO SCSI support, in-flight
57operations were not aborted when stopping the device, rendering
58bus reset ineffective.
59This tunable disables attempts to issue reset bus commands.
60The default value is 1.
61.El
62.Sh DEBUGGING
63To enable debugging prints from the
64.Nm
65driver, set the
66.Bd -literal -offset indent
67hw.vtscsi.X.debug_level
68.Ed
69.Pp
70variable, where X is the adapter number, either in
71.Xr loader.conf 5
72or via
73.Xr sysctl 8 .
74The following bits have the described effects:
75.Bl -tag -width 6n -offset indent
76.It 0x01
77Enable informational prints.
78.It 0x02
79Enable prints for driver errors.
80.It 0x04
81Enable tracing prints.
82.El
83.Sh SEE ALSO
84.Xr virtio 4
85.Sh HISTORY
86The
87.Nm
88driver was written by
89.An Bryan Venteicher Aq Mt bryanv@FreeBSD.org .
90It first appeared in
91.Fx 10.0 .
92