Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
FUSEFS(5)		      File Formats Manual		     FUSEFS(5)

NAME
       fusefs -- File system in	USErspace

SYNOPSIS
       To link into the	kernel:

	     options FUSEFS

       To load as a loadable kernel module:

	     kldload fusefs

DESCRIPTION
       The  fusefs driver implements a file system that	is serviced by a user-
       space program.

       There are many uses for fusefs.	Userspace daemons can access libraries
       or programming languages	that cannot run	in kernel-mode,	 for  example.
       fusefs  is  also	 useful	for developing and debugging file systems, be-
       cause a crash of	the daemon will	not take  down	the  entire  operating
       system.	 Finally, the fusefs API is portable.  Many daemons can	run on
       multiple	operating systems with minimal modifications.

SYSCTL VARIABLES
       The following sysctl(8) variables are available:

       vfs.fusefs.kernelabi_major
	       Major version of	the FUSE kernel	ABI supported by this driver.

       vfs.fusefs.kernelabi_minor
	       Minor version of	the FUSE kernel	ABI supported by this driver.

       vfs.fusefs.data_cache_mode
	       Controls	how fusefs will	cache file data	for pre-7.23 file sys-
	       tems.  A	value of 0 will	disable	caching	entirely.  Every  data
	       access  will be forwarded to the	daemon.	 A value of 1 will se-
	       lect write-through caching.  Reads will be cached  in  the  VFS
	       layer  as  usual.   Writes will be immediately forwarded	to the
	       daemon, and also	added to the cache.  A value of	2 will	select
	       write-back  caching.  Reads and writes will both	be cached, and
	       writes will occasionally	be flushed to the daemon by  the  page
	       daemon.	 Write-back  caching is	usually	unsafe,	especially for
	       FUSE file systems that require network access.

	       FUSE file systems using protocol	7.23 or	 later	specify	 their
	       cache behavior on a per-mountpoint basis, ignoring this sysctl.

       vfs.fusefs.stats.filehandle_count
	       Current number of open FUSE file	handles.

       vfs.fusefs.stats.lookup_cache_hits
	       Total number of lookup cache hits.

       vfs.fusefs.stats.lookup_cache_misses
	       Total number of lookup cache misses.

       vfs.fusefs.stats.node_count
	       Current number of allocated FUSE	vnodes.

       vfs.fusefs.stats.ticket_count
	       Current	number	of  allocated  FUSE  tickets, which is roughly
	       equal  to  the  number  of  FUSE	 operations  currently	 being
	       processed by daemons.

SEE ALSO
       mount_fusefs(8)

HISTORY
       The  fuse  driver was written as	the part of the	FreeBSD	implementation
       of    the    FUSE    userspace	 file	 system	    framework	  (see
       https://github.com/libfuse/libfuse)   and   first   appeared   in   the
       sysutils/fusefs-kmod port, supporting FreeBSD 6.0.  It was added	to the
       base system in FreeBSD 10.0, and	renamed	to fusefs for FreeBSD 12.1.

AUTHORS
       The fuse	driver was originally written by Csaba Henk as a Google	Summer
       of Code project in 2005.	 It was	further	 developed  by	Ilya  Putsikau
       during Google Summer of Code 2011, and that version was integrated into
       the base	system by Attilio Rao <attilio@FreeBSD.org>.

       This manual page	was written by Alan Somers <asomers@FreeBSD.org>.

FreeBSD	13.2			 July 31, 2019			     FUSEFS(5)

NAME | SYNOPSIS | DESCRIPTION | SYSCTL VARIABLES | SEE ALSO | HISTORY | AUTHORS

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=fusefs&manpath=FreeBSD+14.0-RELEASE+and+Ports>

home | help