perfused(8) - NetBSD Manual Pages

PERFUSED(8)             NetBSD System Manager's Manual             PERFUSED(8)


NAME

     perfused -- PUFFS Enabled Relay to FUSE Daemon


SYNOPSIS

     perfused [-fs] [-d types] [-i -fd]


DESCRIPTION

     perfused is a userland daemon implementing the FUSE kernel level API.  It
     creates a /dev/fuse socket for FUSE file system daemons to connect to.
     perfused takes care of mounting the file system using puffs(3).

     When the kernel sends a puffs(3) operation for the mounted file system,
     perfused will translate it into a FUSE request, and will send it to the
     file system daemon through /dev/fuse.  The FUSE reply will be converted
     back into a puffs(3) reply and will be relayed to the kernel.

     FUSE file system daemons must be modified so that they request perfused
     to perform the mount(2) system call instead of doing it on their own.
     This is done by replacing mount(2) and the open(2) calls for /dev/fuse
     with perfuse_mount() and perfuse_open(), respectively, in their sources.
     libperfuse(3) must be used at link time.  Most FUSE file system daemons
     use libfuse and will work unmodified, provided the modification is done
     in libfuse itself.

     The following options are available:

     -d types    Print additional debug information.  types is a comma-sepa-
                 rated list of information types to print:

                 puffs   Display PUFFS requests and replies.

                 fuse    Display FUSE requests and replies.

                 dump    Dump content of FUSE frames.

                 fh      Display file handle activity.

                 reclaim
                         Display reclaim activity.

                 readdir
                         Display readdir activity.

                 requeue
                         Display requeue activity.

                 sync    Display dirty flags and sync operations.

     -f          Do not fork, but stay in the foreground.

     -i fd       Do not open /dev/fuse but use the socket available from the
                 file descriptor fd.  This is used when perfused is started
                 from libperfuse(3).

     -s          Enable debug output only when receiving SIGINFO.


ENVIRONMENT

     See libperfuse(3) for environment variables affecting perfused behavior.


SIGNALS

     SIGINFO
             If the -s flag was used, toggle debug output.  Do nothing other-
             wise.

     SIGUSR1
             Toggle FUSE operation dump on and off.  When toggling off, the
             trace is is stored in /var/run/perfuse-xxx.trace (xxx is the
             filesystem mount point).


ERRORS

     The program logs to the syslog daemon as facility ``daemon''.  For
     detailed debugging use the -d (debug) option.


SEE ALSO

     mount(2), perfuse_mount(3), puffs(4)


AUTHORS

     The program was written by Emmanuel Dreyfus <manu@NetBSD.org>.


BUGS

     When perfused runs in the foreground (using the -f flag), some processes
     using the FUSE file system will sometimes hang on `uvn_fp2'.

NetBSD 9.2                     January 29, 2012                     NetBSD 9.2