[PATCH v2 093/109] virtiofsd: add man page

["Dr. David Alan Gilbert (git)" <dgilbert@redhat.com>]

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>
---
 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
-- 
2.24.1