xref: /freebsd/share/man/man4/nvd.4 (revision a7623790fb345e6dc986dfd31df0ace115e6f2e4)
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30.\" nvd driver man page.
31.\"
32.\" Author: Jim Harris <jimharris@FreeBSD.org>
33.\"
34.\" $FreeBSD$
35.\"
36.Dd May 18, 2019
37.Dt NVD 4
38.Os
39.Sh NAME
40.Nm nvd
41.Nd NVM Express disk driver
42.Sh SYNOPSIS
43To compile this driver into your kernel,
44place the following lines in your kernel configuration file:
45.Bd -ragged -offset indent
46.Cd "device nvme"
47.Cd "device nvd"
48.Ed
49.Pp
50Or, to load the driver as a module at boot, place the following lines in
51.Xr loader.conf 5 :
52.Bd -literal -offset indent
53nvme_load="YES"
54nvd_load="YES"
55.Ed
56.Sh DESCRIPTION
57The
58.Nm
59driver exposes NVM Express (NVMe) namespaces as disks to the kernel disk
60storage API.
61It depends on the
62.Xr nvme 4
63driver for notification of existing NVMe namespaces and submission of NVM
64I/O commands.
65.Pp
66Device nodes from the
67.Nm
68driver will have the format /dev/nvdX and are
69.Xr GEOM 4
70disks which can be partitioned by
71.Xr geom 8 .
72Note that device nodes from the
73.Xr nvme 4
74driver are not
75.Xr GEOM 4
76disks and cannot be partitioned.
77.Sh CONFIGURATION
78The
79.Nm
80driver defines a system-wide maximum delete size for NVMe devices.
81The default is 1GB.
82To select a different value, set the following tunable in
83.Xr loader.conf 5 :
84.Bd -literal -offset indent
85hw.nvd.delete_max=<delete size in bytes>
86.Ed
87.Sh SEE ALSO
88.Xr GEOM 4 ,
89.Xr nda 4 ,
90.Xr nvme 4 ,
91.Xr geom 8 ,
92.Xr nvmecontrol 8 ,
93.Xr disk 9
94.Sh HISTORY
95The
96.Nm
97driver first appeared in
98.Fx 9.2 .
99.Sh AUTHORS
100.An -nosplit
101The
102.Nm
103driver was developed by Intel and originally written by
104.An Jim Harris Aq Mt jimharris@FreeBSD.org ,
105with contributions from Joe Golio at EMC.
106.Pp
107This man page was written by
108.An Jim Harris Aq Mt jimharris@FreeBSD.org .
109