xref: /freebsd/share/man/man4/nvd.4 (revision 7cc42f6d25ef2e19059d088fa7d4853fe9afefb5)
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.\" $FreeBSD$
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