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

perfused — PUFFS Enabled Relay to FUSE Daemon

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

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 () and (), 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:

types
Print additional debug information. types is a comma-separated 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.
Do not fork, but stay in the foreground.
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).
Enable debug output only when receiving SIGINFO.

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

If the -s flag was used, toggle debug output. Do nothing otherwise.
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).

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

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

The program was written by Emmanuel Dreyfus ⟨manu@NetBSD.org⟩.

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

January 29, 2012 NetBSD 11.0