On 1/21/20 1:24 PM, Dr. David Alan Gilbert (git) wrote:
> From: Stefan Hajnoczi <stefanha@redhat.com>
>
> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
>
> with additions by:
> Signed-off-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
>
> Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
> Makefile | 7 +++
> tools/virtiofsd/virtiofsd.texi | 104 +++++++++++++++++++++++++++++++++
> 2 files changed, 111 insertions(+)
> create mode 100644 tools/virtiofsd/virtiofsd.texi
>
> diff --git a/Makefile b/Makefile
> index 2375a1f81c..ba7e2e5ebc 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -353,6 +353,9 @@ DOCS+=$(MANUAL_BUILDDIR)/index.html
> ifdef CONFIG_VIRTFS
> DOCS+=fsdev/virtfs-proxy-helper.1
> endif
> +ifdef CONFIG_LINUX
> +DOCS+=tools/virtiofsd/virtiofsd.1
> +endif
> ifdef CONFIG_TRACE_SYSTEMTAP
> DOCS+=scripts/qemu-trace-stap.1
> endif
> @@ -857,6 +860,9 @@ ifdef CONFIG_VIRTFS
> $(INSTALL_DIR) "$(DESTDIR)$(mandir)/man1"
> $(INSTALL_DATA) fsdev/virtfs-proxy-helper.1 "$(DESTDIR)$(mandir)/man1"
> endif
> +ifdef CONFIG_LINUX
> + $(INSTALL_DATA) tools/virtiofsd/virtiofsd.1 "$(DESTDIR)$(mandir)/man1"
> +endif
>
> install-datadir:
> $(INSTALL_DIR) "$(DESTDIR)$(qemu_datadir)"
> @@ -1065,6 +1071,7 @@ qemu.1: qemu-doc.texi qemu-options.texi qemu-monitor.texi qemu-monitor-info.texi
> qemu.1: qemu-option-trace.texi
> qemu-img.1: qemu-img.texi qemu-option-trace.texi qemu-img-cmds.texi
> fsdev/virtfs-proxy-helper.1: fsdev/virtfs-proxy-helper.texi
> +tools/virtiofsd/virtiofsd.1: tools/virtiofsd/virtiofsd.texi
> qemu-nbd.8: qemu-nbd.texi qemu-option-trace.texi
> docs/qemu-block-drivers.7: docs/qemu-block-drivers.texi
> docs/qemu-cpu-models.7: docs/qemu-cpu-models.texi
> diff --git a/tools/virtiofsd/virtiofsd.texi b/tools/virtiofsd/virtiofsd.texi
> new file mode 100644
> index 0000000000..d7a2528f7d
> --- /dev/null
> +++ b/tools/virtiofsd/virtiofsd.texi
> @@ -0,0 +1,104 @@
> +@example
> +@c man begin SYNOPSIS
> +@command{virtiofsd} [OPTION] @option{--socket-path=}@var{path}|@option{--fd=}@var{fdnum} @option{-o source=}@var{path}
> +@c man end
> +@end example
> +
> +@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. 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 flock|no_flock
> +enable/disable flock.
> +The default is @var{no_flock}.
> +@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 norace
> +Disable racy fallback.
> +The default is false.
> +@item -o posix_lock|no_posix_lock
> +Enable/Disable remote posix lock.
> +The default is @var{posix_lock}.
> +@item -o readdirplus|no_readdirplus
> +Enable/Disable readdirplus.
> +The default is @var{readdirplus}
> +@item -o source=@var{path}
> +Share host directory tree located at @var{path}. This option is required.
> +@item -o timeout=<number>
> +I/O timeout (second).
> +The default depends on cache= option.
> +@item -o writeback|no_writeback
> +Enable/Disable writeback cache. The cache alows the FUSE client
> +to buffer and merge write requests.
> +The default is @var{no_writeback}.
> +@item -o xattr|no_xattr
> +Enable/Disable Extended attributes (xattr) of the files and directories.
> +The default is @var{no_xattr}.
> +@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.
> +@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 myfs /mnt
> +@end example
> +@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.
> +
> +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
>