/share/man/man5/tmpfs.5

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 50.\" $FreeBSD$
 51.\"
 52.Dd April 23, 2012
 53.Dt TMPFS 5
 54.Os
 55.Sh NAME
 56.Nm tmpfs
 57.Nd "efficient memory file system"
 58.Sh SYNOPSIS
 59To compile this driver into the kernel,
 60place the following line in your
 61kernel configuration file:
 62.Bd -ragged -offset indent
 63.Cd "options TMPFS"
 64.Ed
 65.Pp
 66Alternatively, to load the driver as a
 67module at boot time, place the following line in
 68.Xr loader.conf 5 :
 69.Bd -literal -offset indent
 70tmpfs_load="YES"
 71.Ed
 72.Sh DESCRIPTION
 73The
 74.Nm
 75driver will permit the
 76.Fx
 77kernel to access
 78.Tn tmpfs
 79file systems.
 80.Sh OPTIONS
 81The following options are available when
 82mounting
 83.Nm
 84file systems:
 85.Bl -tag -width indent
 86.It Cm gid
 87Specifies the group ID of the root inode of the file system.
 88Defaults to the mount point's GID.
 89.It Cm uid
 90Specifies the user ID of the root inode of the file system.
 91Defaults to the mount point's UID.
 92.It Cm mode
 93Specifies the mode (in octal notation) of the root inode of the file system.
 94Defaults to the mount point's mode.
 95.It Cm inodes
 96Specifies the maximum number of nodes available to the file system.
 97If not specified, the file system chooses a reasonable maximum based on
 98the file system size, which can be limited with the
 99.Cm size
100option.
101.It Cm size
102Specifies the total file system size in bytes.
103If zero (the default) or a value larger than SIZE_MAX - PAGE_SIZE
104is given, the available amount of memory (including
105main memory and swap space) will be used.
106.It Cm maxfilesize
107Specifies the maximum file size in bytes.
108Defaults to the maximum possible value.
109.El
110.Sh EXAMPLES
111To mount a
112.Nm
113memory file system:
114.Pp
115.Dl "mount -t tmpfs tmpfs /tmp"
116.Sh SEE ALSO
117.Xr nmount 2 ,
118.Xr unmount 2 ,
119.Xr fstab 5 ,
120.Xr mdmfs 8 ,
121.Xr mount 8
122.Sh HISTORY
123The
124.Nm
125driver first appeared in
126.Fx 7.0 .
127.Sh AUTHORS
128.An -nosplit
129The
130.Nm
131kernel implementation was written by
132.An Julio M. Merino Vidal Aq jmmv@NetBSD.org
133as a Google SoC project.
134.Pp
135.An Rohit Jalan
136and others ported it from
137.Nx
138to
139.Fx .
140.Pp
141This manual page was written by
142.An Xin LI Aq delphij@FreeBSD.org .
143.Sh BUGS
144Some file system mount time options may not be well-supported.