xref: /freebsd/share/man/man4/nda.4 (revision 1adc28f5a882d58135de190afdbf323bc43bff3a)
152467047SWarner Losh.\"
252467047SWarner Losh.\" Copyright (c) 2017 Netflix, Inc.
34d21bbd1SWarner Losh.\"
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54d21bbd1SWarner Losh.\" modification, are permitted provided that the following conditions
64d21bbd1SWarner Losh.\" are met:
74d21bbd1SWarner Losh.\" 1. Redistributions of source code must retain the above copyright
84d21bbd1SWarner Losh.\"    notice, this list of conditions and the following disclaimer.
94d21bbd1SWarner Losh.\"
104d21bbd1SWarner Losh.\" 2. Redistributions in binary form must reproduce the above copyright
114d21bbd1SWarner Losh.\"    notice, this list of conditions and the following disclaimer in the
124d21bbd1SWarner Losh.\"    documentation and/or other materials provided with the distribution.
134d21bbd1SWarner Losh.\"
144d21bbd1SWarner Losh.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
154d21bbd1SWarner Losh.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
164d21bbd1SWarner Losh.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
174d21bbd1SWarner Losh.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
184d21bbd1SWarner Losh.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
194d21bbd1SWarner Losh.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
204d21bbd1SWarner Losh.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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244d21bbd1SWarner Losh.\" SUCH DAMAGE.
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264d21bbd1SWarner Losh.\" $FreeBSD$
274d21bbd1SWarner Losh.\"
284d21bbd1SWarner Losh.Dd December 20, 2017
294d21bbd1SWarner Losh.Dt NDA 4
304d21bbd1SWarner Losh.Os
314d21bbd1SWarner Losh.Sh NAME
324d21bbd1SWarner Losh.Nm nda
334d21bbd1SWarner Losh.Nd NVMe Direct Access device driver
344d21bbd1SWarner Losh.Sh SYNOPSIS
354d21bbd1SWarner Losh.Cd device nvme
364d21bbd1SWarner Losh.Cd device scbus
374d21bbd1SWarner Losh.Sh DESCRIPTION
384d21bbd1SWarner LoshThe
394d21bbd1SWarner Losh.Nm
404d21bbd1SWarner Loshdriver provides support for direct access devices, implementing the
414d21bbd1SWarner Losh.Tn NVMe
424d21bbd1SWarner Loshcommand protocol, that are attached to the system through a host adapter
434d21bbd1SWarner Loshsupported by the CAM subsystem.
444d21bbd1SWarner Losh.Sh SYSCTL VARIABLES
454d21bbd1SWarner LoshThe following variables are available as both
464d21bbd1SWarner Losh.Xr sysctl 8
474d21bbd1SWarner Loshvariables and
484d21bbd1SWarner Losh.Xr loader 8
494d21bbd1SWarner Loshtunables:
504d21bbd1SWarner Losh.Bl -tag -width 12
514d21bbd1SWarner Losh.It Va kern.cam.nda.sort_io_queue
524d21bbd1SWarner Losh.Pp
534d21bbd1SWarner LoshThis variable determines whether the software queued entries are
544d21bbd1SWarner Loshsorted in LBA order or not.
554d21bbd1SWarner LoshSorting is almost always a waste of time.
564d21bbd1SWarner LoshThe default is to not sort.
574d21bbd1SWarner Losh.El
584d21bbd1SWarner Losh.Pp
594d21bbd1SWarner LoshThe following report per-device settings, and are read-only unless
604d21bbd1SWarner Loshotherwise indicated. Replace
614d21bbd1SWarner Losh.Va N
624d21bbd1SWarner Loshwith the device unit number.
634d21bbd1SWarner Losh.Bl -tag -width 12
644d21bbd1SWarner Losh.It Va kern.cam.nda.N.rotating
654d21bbd1SWarner Losh.Pp
664d21bbd1SWarner LoshThis variable reports whether the storage volume is spinning or
674d21bbd1SWarner Loshflash.
684d21bbd1SWarner LoshIt's value is hard coded to 0 indicating flash.
694d21bbd1SWarner Losh.It Va kern.cam.nda.N.unmapped_io
704d21bbd1SWarner LoshThis variable reports whether the
714d21bbd1SWarner Losh.Nm
724d21bbd1SWarner Loshdriver accepts unmapped I/O for this unit.
73*1adc28f5SChristian Brueffer.El
744d21bbd1SWarner Losh.Sh FILES
754d21bbd1SWarner Losh.Bl -tag -width ".Pa /dev/nda*" -compact
764d21bbd1SWarner Losh.It Pa /dev/nda*
774d21bbd1SWarner LoshNVMe storage device nodes
784d21bbd1SWarner Losh.El
794d21bbd1SWarner Losh.Sh SEE ALSO
80*1adc28f5SChristian Brueffer.Xr nvd 4 ,
81*1adc28f5SChristian Brueffer.Xr nvme 4
824d21bbd1SWarner Losh.Sh HISTORY
834d21bbd1SWarner LoshThe
844d21bbd1SWarner Losh.Nm
854d21bbd1SWarner Loshdriver first appeared in
864d21bbd1SWarner Losh.Fx 12.0 .
874d21bbd1SWarner Losh.Sh AUTHORS
884d21bbd1SWarner Losh.An Warner Losh Aq Mt imp@FreeBSD.org
89