* Daniel P. Berrangé (berra...@redhat.com) wrote: > On Thu, Dec 12, 2019 at 04:38:52PM +0000, Dr. David Alan Gilbert (git) wrote: > > From: Stefan Hajnoczi <stefa...@redhat.com> > > > > Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com> > > --- > > Makefile | 7 +++ > > tools/virtiofsd/virtiofsd.texi | 85 ++++++++++++++++++++++++++++++++++ > > 2 files changed, 92 insertions(+) > > create mode 100644 tools/virtiofsd/virtiofsd.texi > > Reviewed-by: Daniel P. Berrangé <berra...@redhat.com>
Thanks. > with some notes at the very end <snip> > > +@c man begin DESCRIPTION > > + > > +Share a host directory tree with a guest through a virtio-fs device. This > > +program is a vhost-user backend that implements the virtio-fs device. Each > > +virtio-fs device instance requires its own virtiofsd process. > > + > > +This program is designed to work with QEMU's @code{--device > > vhost-user-fs-pci} > > +but should work with any virtual machine monitor (VMM) that supports > > +vhost-user. See the EXAMPLES section below. > > + > > +This program must be run as the root user. > > So there's no way for an unprivileged user to do file sharing like they > can with 9p right now ? Correct. (Which also makes it a pain for using in a make check) > > Upon startup the program will > > +switch into a new file system namespace with the shared directory tree as > > its > > +root. This prevents "file system escapes" due to symlinks and other file > > +system objects that might lead to files outside the shared directory. The > > +program also sandboxes itself using seccomp(2) to prevent ptrace(2) and > > other > > +vectors that could allow an attacker to compromise the system after gaining > > +control of the virtiofsd process. > > + > > +@c man end > > + > > +@c man begin OPTIONS > > +@table @option > > +@item -h, --help > > +Print help. > > +@item -V, --version > > +Print version. > > +@item -d, -o debug > > +Enable debug output. > > +@item --syslog > > +Print log messages to syslog instead of stderr. > > +@item -o log_level=@var{level} > > +Print only log messages matching @var{level} or more severe. @var{level} > > is > > +one of @code{err}, @code{warn}, @code{info}, or @code{debug}. The default > > is > > +@var{info}. > > +@item -o source=@var{path} > > +Share host directory tree located at @var{path}. This option is required. > > +@item --socket-path=@var{path}, -o vhost_user_socket=@var{path} > > +Listen on vhost-user UNIX domain socket at @var{path}. > > +@item --fd=@var{fdnum} > > +Accept connections from vhost-user UNIX domain socket file descriptor > > @var{fdnum}. The file descriptor must already be listening for connections. > > +@item --thread-pool-size=@var{num} > > +Restrict the number of worker threads per request queue to @var{num}. The > > default is 64. > > +@item --cache=@code{none}|@code{auto}|@code{always} > > +Select the desired trade-off between coherency and performance. > > @code{none} > > +forbids the FUSE client from caching to achieve best coherency at the cost > > of > > +performance. @code{auto} acts similar to NFS with a 1 second metadata > > cache > > +timeout. @code{always} sets a long cache lifetime at the expense of > > coherency. > > +@item --writeback > > +Enable writeback cache, allowing the FUSE client to buffer and merge write > > requests. > > +@end table > > +@c man end > > + > > +@c man begin EXAMPLES > > +Export @code{/var/lib/fs/vm001/} on vhost-user UNIX domain socket > > @code{/var/run/vm001-vhost-fs.sock}: > > + > > +@example > > +host# virtiofsd --socket-path=/var/run/vm001-vhost-fs.sock -o > > source=/var/lib/fs/vm001 > > +host# qemu-system-x86_64 \ > > + -chardev socket,id=char0,path=/var/run/vm001-vhost-fs.sock \ > > + -device vhost-user-fs-pci,chardev=char0,tag=myfs \ > > + -object memory-backend-file,id=mem,size=4G,mem-path=/dev/shm,share=on \ > > + -numa node,memdev=mem \ > > + ... > > +guest# mount -t virtio_fs \ > > + -o > > default_permissions,allow_other,user_id=0,group_id=0,rootmode=040000,dax \ > > + myfs /mnt > > +@end example > > +@c man end > > + > > +@ignore > > +@setfilename virtiofsd > > +@settitle QEMU virtio-fs shared file system daemon > > + > > +@c man begin AUTHOR > > s/AUTHOR/COPYRIGHT/ OK > since this isn't providing any author information. > > > +Copyright (C) 2019 Red Hat, Inc. > > 2019-2020 ! Time flies... > And now insert > > @c man end > @c man begin LICENSE > > > +This is free software; see the source for copying conditions. There is NO > > +warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. > > +@c man end > > +@end ignore Hmm, so it ends up like: @c man end @ignore @setfilename virtiofsd @settitle QEMU virtio-fs shared file system daemon @c man begin COPYRIGHT Copyright (C) 2019-2020 Red Hat, Inc. @c man end @c man begin LICENSE This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. @c man end @end ignore That results in: COPYRIGHT Copyright (C) 2019-2020 Red Hat, Inc. but with no license printed. That's from after a make doing a nroff -man ./tools/virtiofsd/virtiofsd.1 |more is that what's expected? I'd expected to see the license somewhere. Dave > > > > Regards, > Daniel > -- > |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| > |: https://libvirt.org -o- https://fstop138.berrange.com :| > |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :| -- Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK