xref: /freebsd/share/man/man4/nvd.4 (revision 257e70f1d5ee61037c8c59b116538d3b6b1427a2)
1.\"
2.\" Copyright (c) 2012-2016 Intel Corporation
3.\" All rights reserved.
4.\"
5.\" Redistribution and use in source and binary forms, with or without
6.\" modification, are permitted provided that the following conditions
7.\" are met:
8.\" 1. Redistributions of source code must retain the above copyright
9.\"    notice, this list of conditions, and the following disclaimer,
10.\"    without modification.
11.\" 2. Redistributions in binary form must reproduce at minimum a disclaimer
12.\"    substantially similar to the "NO WARRANTY" disclaimer below
13.\"    ("Disclaimer") and any redistribution must be conditioned upon
14.\"    including a substantially similar Disclaimer requirement for further
15.\"    binary redistribution.
16.\"
17.\" NO WARRANTY
18.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19.\" "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20.\" LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
21.\" A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22.\" HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
26.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
27.\" IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28.\" POSSIBILITY OF SUCH DAMAGES.
29.\"
30.\" nvd driver man page.
31.\"
32.\" Author: Jim Harris <jimharris@FreeBSD.org>
33.\"
34.Dd May 18, 2019
35.Dt NVD 4
36.Os
37.Sh NAME
38.Nm nvd
39.Nd NVM Express disk driver
40.Sh SYNOPSIS
41To compile this driver into your kernel,
42place the following lines in your kernel configuration file:
43.Bd -ragged -offset indent
44.Cd "device nvme"
45.Cd "device nvd"
46.Ed
47.Pp
48Or, to load the driver as a module at boot, place the following lines in
49.Xr loader.conf 5 :
50.Bd -literal -offset indent
51nvme_load="YES"
52nvd_load="YES"
53.Ed
54.Sh DESCRIPTION
55The
56.Nm
57driver exposes NVM Express (NVMe) namespaces as disks to the kernel disk
58storage API.
59It depends on the
60.Xr nvme 4
61driver for notification of existing NVMe namespaces and submission of NVM
62I/O commands.
63.Pp
64Device nodes from the
65.Nm
66driver will have the format /dev/nvdX and are
67.Xr GEOM 4
68disks which can be partitioned by
69.Xr geom 8 .
70Note that device nodes from the
71.Xr nvme 4
72driver are not
73.Xr GEOM 4
74disks and cannot be partitioned.
75.Sh CONFIGURATION
76The
77.Nm
78driver defines a system-wide maximum delete size for NVMe devices.
79The default is 1GB.
80To select a different value, set the following tunable in
81.Xr loader.conf 5 :
82.Bd -literal -offset indent
83hw.nvd.delete_max=<delete size in bytes>
84.Ed
85.Sh SEE ALSO
86.Xr GEOM 4 ,
87.Xr nda 4 ,
88.Xr nvme 4 ,
89.Xr geom 8 ,
90.Xr nvmecontrol 8 ,
91.Xr disk 9
92.Sh HISTORY
93The
94.Nm
95driver first appeared in
96.Fx 9.2 .
97.Sh AUTHORS
98.An -nosplit
99The
100.Nm
101driver was developed by Intel and originally written by
102.An Jim Harris Aq Mt jimharris@FreeBSD.org ,
103with contributions from Joe Golio at EMC.
104.Pp
105This man page was written by
106.An Jim Harris Aq Mt jimharris@FreeBSD.org .
107