FreeBSD manual
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TARFS(5) FreeBSD File Formats Manual TARFS(5)
NAME
tarfs - tarball filesystem
SYNOPSIS
To compile this driver into the kernel, place the following line in your
kernel configuration file:
options TARFS
Alternatively, to load the driver as a module at boot time, place the
following line in loader.conf(5):
tarfs_load="YES"
DESCRIPTION
The tarfs driver implements a read-only filesystem backed by a tar(5)
file. Currently, only POSIX archives, optionally compressed with
zstd(1), are supported.
The preferred I/O size for tarfs filesystems can be adjusted using the
vfs.tarfs.ioshift sysctl setting and tunable. Setting it to 0 will reset
it to its default value. Note that changes to this setting only apply to
filesystems mounted after the change.
DIAGNOSTICS
If enabled by the TARFS_DEBUG kernel option, the vfs.tarfs.debug sysctl
setting can be used to control debugging output from the tarfs driver.
Debugging output for individual sections of the driver can be enabled by
adding together the relevant values from the table below.
0x01 Memory allocations
0x02 Checksum calculations
0x04 Filesystem operations (vfsops)
0x08 Path lookups
0x10 File operations (vnops)
0x20 General I/O
0x40 Decompression
0x80 Decompression index
0x100 Sparse file mapping
0x200 Bounce buffer usage
SEE ALSO
tar(1), zstd(1), fstab(5), tar(5), mount(8), sysctl(8)
HISTORY
The tarfs driver was developed by Stephen J. Kiernan <stevek@FreeBSD.org>
and Dag-Erling Smorgrav <des@FreeBSD.org> for Juniper Networks and Klara
Systems. This manual page was written by Dag-Erling Smorgrav
<des@FreeBSD.org> for Juniper Networks and Klara Systems.
FreeBSD 14.0-RELEASE-p11 February 14, 2023 FreeBSD 14.0-RELEASE-p11