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Convert TNF licenses to new 2 clause variant
2008-04-30 17:10:46 +04:00
.\" $NetBSD: mount_tmpfs.8,v 1.14 2008/04/30 13:10:53 martin Exp $
Initial addition of tmpfs, an efficient memory file-system. This project was developed as part of Google's Summer of Code 2005 program. This change adds the kernel code, the mount_tmpfs utility, a regression test suite and does all other related changes to integrate these. The file-system is still *experimental*. Therefore, it is disabled by default in all kernels. However, as typically done, a commented-out entry is added in them to ease its setup. Note that I haven't commited the required mountd(8) changes to be able to export tmpfs file-systems because NFS support is still very unstable and because, before enabling it, I'd like to do some other changes. OK'ed by my project mentor, William Studenmund (wrstuden@).
2005-09-10 23:20:48 +04:00
.\"
tmpfs is not considered experimental any more. OK'ed by core@.
2006-11-11 22:01:30 +03:00
.\" Copyright (c) 2005, 2006 The NetBSD Foundation, Inc.
Initial addition of tmpfs, an efficient memory file-system. This project was developed as part of Google's Summer of Code 2005 program. This change adds the kernel code, the mount_tmpfs utility, a regression test suite and does all other related changes to integrate these. The file-system is still *experimental*. Therefore, it is disabled by default in all kernels. However, as typically done, a commented-out entry is added in them to ease its setup. Note that I haven't commited the required mountd(8) changes to be able to export tmpfs file-systems because NFS support is still very unstable and because, before enabling it, I'd like to do some other changes. OK'ed by my project mentor, William Studenmund (wrstuden@).
2005-09-10 23:20:48 +04:00
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
Kill the tmpfs(9) manual page; it was just documenting internal details of tmpfs' "API" and was already rotting. Instead, merge all the relevant comments into the code. This includes acknowledgements to Google's Summer of Code 2005 program (they were in the AUTHORS section of tmpfs(9) before), so all the files need to be changed to include this sentence alongside the title. (Note that this was not a requirement of the program.)
2005-09-23 19:36:15 +04:00
.\" by Julio M. Merino Vidal, developed as part of Google's Summer of Code
.\" 2005 program.
Initial addition of tmpfs, an efficient memory file-system. This project was developed as part of Google's Summer of Code 2005 program. This change adds the kernel code, the mount_tmpfs utility, a regression test suite and does all other related changes to integrate these. The file-system is still *experimental*. Therefore, it is disabled by default in all kernels. However, as typically done, a commented-out entry is added in them to ease its setup. Note that I haven't commited the required mountd(8) changes to be able to export tmpfs file-systems because NFS support is still very unstable and because, before enabling it, I'd like to do some other changes. OK'ed by my project mentor, William Studenmund (wrstuden@).
2005-09-10 23:20:48 +04:00
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
The first non-optional parameter is ignored by this program. ok'ed by jmmv@.
2008-02-13 17:21:57 +03:00
.Dd February 13, 2008
Initial addition of tmpfs, an efficient memory file-system. This project was developed as part of Google's Summer of Code 2005 program. This change adds the kernel code, the mount_tmpfs utility, a regression test suite and does all other related changes to integrate these. The file-system is still *experimental*. Therefore, it is disabled by default in all kernels. However, as typically done, a commented-out entry is added in them to ease its setup. Note that I haven't commited the required mountd(8) changes to be able to export tmpfs file-systems because NFS support is still very unstable and because, before enabling it, I'd like to do some other changes. OK'ed by my project mentor, William Studenmund (wrstuden@).
2005-09-10 23:20:48 +04:00
.Dt MOUNT_TMPFS 8
.Os
.Sh NAME
.Nm mount_tmpfs
.Nd mount an efficient memory file system
.Sh SYNOPSIS
.Nm
.Op Fl g Ar group
.Op Fl m Ar mode
.Op Fl n Ar nodes
.Op Fl o Ar options
.Op Fl s Ar size
.Op Fl u Ar user
.Ar tmpfs
.Ar mount_point
.Sh DESCRIPTION
The
.Nm
command attaches an instance of the efficient memory file system to the
global file system namespace.
The first non-optional parameter is ignored by this program. ok'ed by jmmv@.
2008-02-13 17:21:57 +03:00
The
.Ar tmpfs
parameter only exists for compatibility with the other mount commands and
is ignored.
Initial addition of tmpfs, an efficient memory file-system. This project was developed as part of Google's Summer of Code 2005 program. This change adds the kernel code, the mount_tmpfs utility, a regression test suite and does all other related changes to integrate these. The file-system is still *experimental*. Therefore, it is disabled by default in all kernels. However, as typically done, a commented-out entry is added in them to ease its setup. Note that I haven't commited the required mountd(8) changes to be able to export tmpfs file-systems because NFS support is still very unstable and because, before enabling it, I'd like to do some other changes. OK'ed by my project mentor, William Studenmund (wrstuden@).
2005-09-10 23:20:48 +04:00
The directory specified by
.Ar mount_point
Inherit owner, group and mode of the mount directory so that mounting a tmpfs over, e.g., /tmp, is trivial.
2005-09-25 12:08:12 +04:00
is converted to an absolute path before use and its attributes (owner,
group and mode) are inherited unless explicitly overriden by the options
described below.
Initial addition of tmpfs, an efficient memory file-system. This project was developed as part of Google's Summer of Code 2005 program. This change adds the kernel code, the mount_tmpfs utility, a regression test suite and does all other related changes to integrate these. The file-system is still *experimental*. Therefore, it is disabled by default in all kernels. However, as typically done, a commented-out entry is added in them to ease its setup. Note that I haven't commited the required mountd(8) changes to be able to export tmpfs file-systems because NFS support is still very unstable and because, before enabling it, I'd like to do some other changes. OK'ed by my project mentor, William Studenmund (wrstuden@).
2005-09-10 23:20:48 +04:00
.Pp
The following options are supported:
.Bl -tag -width XoXoptions
.It Fl g Ar group
Specifies the group name or GID of the root inode of the file system.
Inherit owner, group and mode of the mount directory so that mounting a tmpfs over, e.g., /tmp, is trivial.
2005-09-25 12:08:12 +04:00
Defaults to the mount point's GID.
Initial addition of tmpfs, an efficient memory file-system. This project was developed as part of Google's Summer of Code 2005 program. This change adds the kernel code, the mount_tmpfs utility, a regression test suite and does all other related changes to integrate these. The file-system is still *experimental*. Therefore, it is disabled by default in all kernels. However, as typically done, a commented-out entry is added in them to ease its setup. Note that I haven't commited the required mountd(8) changes to be able to export tmpfs file-systems because NFS support is still very unstable and because, before enabling it, I'd like to do some other changes. OK'ed by my project mentor, William Studenmund (wrstuden@).
2005-09-10 23:20:48 +04:00
.It Fl m Ar mode
Specifies the mode (in octal notation) of the root inode of the file system.
Inherit owner, group and mode of the mount directory so that mounting a tmpfs over, e.g., /tmp, is trivial.
2005-09-25 12:08:12 +04:00
Defaults to the mount point's mode.
Initial addition of tmpfs, an efficient memory file-system. This project was developed as part of Google's Summer of Code 2005 program. This change adds the kernel code, the mount_tmpfs utility, a regression test suite and does all other related changes to integrate these. The file-system is still *experimental*. Therefore, it is disabled by default in all kernels. However, as typically done, a commented-out entry is added in them to ease its setup. Note that I haven't commited the required mountd(8) changes to be able to export tmpfs file-systems because NFS support is still very unstable and because, before enabling it, I'd like to do some other changes. OK'ed by my project mentor, William Studenmund (wrstuden@).
2005-09-10 23:20:48 +04:00
.It Fl n Ar nodes
wiz@ remembers that the preferred way to spell file-system in NetBSD is file system.
2005-09-11 02:28:57 +04:00
Specifies the maximum number of nodes available to the file system.
Note that meta data is stored in non-pageable memory and the problems this may carry. Suggested by Greg Troxel in private mail.
2006-12-19 17:50:49 +03:00
If not specified, the file system chooses a reasonable maximum given its
size at mount time, which can be limited with
.Fl s .
Initial addition of tmpfs, an efficient memory file-system. This project was developed as part of Google's Summer of Code 2005 program. This change adds the kernel code, the mount_tmpfs utility, a regression test suite and does all other related changes to integrate these. The file-system is still *experimental*. Therefore, it is disabled by default in all kernels. However, as typically done, a commented-out entry is added in them to ease its setup. Note that I haven't commited the required mountd(8) changes to be able to export tmpfs file-systems because NFS support is still very unstable and because, before enabling it, I'd like to do some other changes. OK'ed by my project mentor, William Studenmund (wrstuden@).
2005-09-10 23:20:48 +04:00
.It Fl o Ar options
Options are specified with a
.Fl o
flag followed by a comma-separated string of options.
See the
.Xr mount 8
man page for possible options and their meanings.
.It Fl s Ar size
Specifies the total file system size in bytes.
If zero is given (the default), the available amount of memory (including
main memory and swap space) will be used.
Note that four megabytes are always reserved for the system and cannot
wiz@ remembers that the preferred way to spell file-system in NetBSD is file system.
2005-09-11 02:28:57 +04:00
be assigned to the file system.
Initial addition of tmpfs, an efficient memory file-system. This project was developed as part of Google's Summer of Code 2005 program. This change adds the kernel code, the mount_tmpfs utility, a regression test suite and does all other related changes to integrate these. The file-system is still *experimental*. Therefore, it is disabled by default in all kernels. However, as typically done, a commented-out entry is added in them to ease its setup. Note that I haven't commited the required mountd(8) changes to be able to export tmpfs file-systems because NFS support is still very unstable and because, before enabling it, I'd like to do some other changes. OK'ed by my project mentor, William Studenmund (wrstuden@).
2005-09-10 23:20:48 +04:00
.It Fl u Ar user
Specifies the user name or UID of the root inode of the file system.
Inherit owner, group and mode of the mount directory so that mounting a tmpfs over, e.g., /tmp, is trivial.
2005-09-25 12:08:12 +04:00
Defaults to the mount point's UID.
Initial addition of tmpfs, an efficient memory file-system. This project was developed as part of Google's Summer of Code 2005 program. This change adds the kernel code, the mount_tmpfs utility, a regression test suite and does all other related changes to integrate these. The file-system is still *experimental*. Therefore, it is disabled by default in all kernels. However, as typically done, a commented-out entry is added in them to ease its setup. Note that I haven't commited the required mountd(8) changes to be able to export tmpfs file-systems because NFS support is still very unstable and because, before enabling it, I'd like to do some other changes. OK'ed by my project mentor, William Studenmund (wrstuden@).
2005-09-10 23:20:48 +04:00
.El
.Pp
Every option that accepts a numerical value as its argument can take a
trailing
.Sq b
to indicate bytes (the default), a trailing
.Sq k
to indicate kilobytes, a trailing
.Sq M
to indicate megabytes or a trailing
.Sq G
to indicate gigabytes.
Ignore case of trailing unit specifiers in size measures to remove confusion.
2005-09-25 12:11:50 +04:00
Note that both lowercase and uppercase forms of these letters are allowed.
Add an EXAMPLES section. Requested by martti@ to clarify the purpose of the field before the mount point.
2005-09-30 00:54:23 +04:00
.Sh EXAMPLES
The following command mounts a tmpfs instance over the
.Pa /tmp
directory, inheriting its owner, group and mode settings:
.Pp
.Ic "mount -t tmpfs tmpfs /tmp"
.Pp
The following command mounts a tmpfs instance over the
.Pa /mnt
directory, setting a 20 megabytes limit in space, owned by the
.Sq joe
user and belonging to the
.Sq users
group, with a restricted 0700 mode:
.Pp
.Ic "mount -t tmpfs -o -s20M -o -ujoe -o -gusers -o -m0700 tmpfs /mnt"
Point to the share/examples/fstab/fstab.ramdisk file for some more information.
2005-12-24 16:02:53 +03:00
.Pp
See
.Pa /usr/share/examples/fstab/fstab.ramdisk
for some examples on how to add tmpfs entries to
.Pa /etc/fstab .
Initial addition of tmpfs, an efficient memory file-system. This project was developed as part of Google's Summer of Code 2005 program. This change adds the kernel code, the mount_tmpfs utility, a regression test suite and does all other related changes to integrate these. The file-system is still *experimental*. Therefore, it is disabled by default in all kernels. However, as typically done, a commented-out entry is added in them to ease its setup. Note that I haven't commited the required mountd(8) changes to be able to export tmpfs file-systems because NFS support is still very unstable and because, before enabling it, I'd like to do some other changes. OK'ed by my project mentor, William Studenmund (wrstuden@).
2005-09-10 23:20:48 +04:00
.Sh SEE ALSO
.Xr fstab 5 ,
Kill reference to tmpfs(9). Noticed by "pancake".
2005-09-25 22:27:30 +04:00
.Xr mount 8
Initial addition of tmpfs, an efficient memory file-system. This project was developed as part of Google's Summer of Code 2005 program. This change adds the kernel code, the mount_tmpfs utility, a regression test suite and does all other related changes to integrate these. The file-system is still *experimental*. Therefore, it is disabled by default in all kernels. However, as typically done, a commented-out entry is added in them to ease its setup. Note that I haven't commited the required mountd(8) changes to be able to export tmpfs file-systems because NFS support is still very unstable and because, before enabling it, I'd like to do some other changes. OK'ed by my project mentor, William Studenmund (wrstuden@).
2005-09-10 23:20:48 +04:00
.Sh HISTORY
The
.Nm
utility first appeared in
.Nx 4.0 .
Note that meta data is stored in non-pageable memory and the problems this may carry. Suggested by Greg Troxel in private mail.
2006-12-19 17:50:49 +03:00
.Sh BUGS
File system meta-data is not pageable.
If there is not enough main memory to hold this information, the system may
become unstable or very unresponsive because it will not be able to allocate
required memory.
s/tons/lots/, per simonb@'s suggestion. This looks more formal.
2007-01-03 11:39:29 +03:00
A malicious user could trigger this condition if he could create lots of
Note that meta data is stored in non-pageable memory and the problems this may carry. Suggested by Greg Troxel in private mail.
2006-12-19 17:50:49 +03:00
files inside a size-unbounded tmpfs file system.
Limiting the number of nodes per file system
Nicer macro usage.
2006-12-19 23:33:35 +03:00
.Pq Fl n
Note that meta data is stored in non-pageable memory and the problems this may carry. Suggested by Greg Troxel in private mail.
2006-12-19 17:50:49 +03:00
will prevent this; the default value for this setting is also often adjusted
to an adequate value to resolve this.