diff options
| -rw-r--r-- | MAINTAINERS | 1 | ||||
| -rw-r--r-- | Makefile | 9 | ||||
| -rw-r--r-- | docs/interop/conf.py | 5 | ||||
| -rw-r--r-- | docs/interop/index.rst | 1 | ||||
| -rw-r--r-- | docs/interop/virtiofsd.rst | 120 |
5 files changed, 134 insertions, 2 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index ce46c0a..c7717df 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1613,6 +1613,7 @@ S: Supported F: tools/virtiofsd/* F: hw/virtio/vhost-user-fs* F: include/hw/virtio/vhost-user-fs.h +F: docs/interop/virtiofsd.rst virtio-input M: Gerd Hoffmann <kraxel@redhat.com> @@ -348,6 +348,9 @@ DOCS=qemu-doc.html qemu-doc.txt qemu.1 DOCS+=$(MANUAL_BUILDDIR)/interop/qemu-img.1 DOCS+=$(MANUAL_BUILDDIR)/interop/qemu-nbd.8 DOCS+=$(MANUAL_BUILDDIR)/interop/qemu-ga.8 +ifeq ($(CONFIG_LINUX)$(CONFIG_SECCOMP)$(CONFIG_LIBCAP_NG),yyy) +DOCS+=$(MANUAL_BUILDDIR)/interop/virtiofsd.1 +endif DOCS+=$(MANUAL_BUILDDIR)/system/qemu-block-drivers.7 DOCS+=docs/interop/qemu-qmp-ref.html docs/interop/qemu-qmp-ref.txt docs/interop/qemu-qmp-ref.7 DOCS+=docs/interop/qemu-ga-ref.html docs/interop/qemu-ga-ref.txt docs/interop/qemu-ga-ref.7 @@ -861,6 +864,9 @@ ifdef CONFIG_VIRTFS $(INSTALL_DIR) "$(DESTDIR)$(mandir)/man1" $(INSTALL_DATA) $(MANUAL_BUILDDIR)/interop/virtfs-proxy-helper.1 "$(DESTDIR)$(mandir)/man1" endif +ifeq ($(CONFIG_LINUX)$(CONFIG_SECCOMP)$(CONFIG_LIBCAP_NG),yyy) + $(INSTALL_DATA) docs/interop/virtiofsd.1 "$(DESTDIR)$(mandir)/man1" +endif install-datadir: $(INSTALL_DIR) "$(DESTDIR)$(qemu_datadir)" @@ -1051,7 +1057,8 @@ $(MANUAL_BUILDDIR)/system/index.html: $(call manual-deps,system) $(call build-manual,system,html) $(call define-manpage-rule,interop,\ - qemu-ga.8 qemu-img.1 qemu-nbd.8 qemu-trace-stap.1 virtfs-proxy-helper.1,\ + qemu-ga.8 qemu-img.1 qemu-nbd.8 qemu-trace-stap.1\ + virtiofsd.1 virtfs-proxy-helper.1,\ $(SRC_PATH/qemu-img-cmds.hx)) $(call define-manpage-rule,system,qemu-block-drivers.7) diff --git a/docs/interop/conf.py b/docs/interop/conf.py index b0f3222..b3cda17 100644 --- a/docs/interop/conf.py +++ b/docs/interop/conf.py @@ -27,5 +27,8 @@ man_pages = [ [], 1), ('virtfs-proxy-helper', 'virtfs-proxy-helper', u'QEMU 9p virtfs proxy filesystem helper', - ['M. Mohan Kumar'], 1) + ['M. Mohan Kumar'], 1), + ('virtiofsd', 'virtiofsd', u'QEMU virtio-fs shared file system daemon', + ['Stefan Hajnoczi <stefanha@redhat.com>', + 'Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>'], 1), ] diff --git a/docs/interop/index.rst b/docs/interop/index.rst index 3b763b1..e8455b4 100644 --- a/docs/interop/index.rst +++ b/docs/interop/index.rst @@ -24,3 +24,4 @@ Contents: vhost-user vhost-user-gpu virtfs-proxy-helper + virtiofsd diff --git a/docs/interop/virtiofsd.rst b/docs/interop/virtiofsd.rst new file mode 100644 index 0000000..378594c --- /dev/null +++ b/docs/interop/virtiofsd.rst @@ -0,0 +1,120 @@ +QEMU virtio-fs shared file system daemon +======================================== + +Synopsis +-------- + +**virtiofsd** [*OPTIONS*] + +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 ``--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. + +Options +------- + +.. program:: virtiofsd + +.. option:: -h, --help + + Print help. + +.. option:: -V, --version + + Print version. + +.. option:: -d + + Enable debug output. + +.. option:: --syslog + + Print log messages to syslog instead of stderr. + +.. option:: -o OPTION + + * debug - + Enable debug output. + + * flock|no_flock - + Enable/disable flock. The default is ``no_flock``. + + * log_level=LEVEL - + Print only log messages matching LEVEL or more severe. LEVEL is one of + ``err``, ``warn``, ``info``, or ``debug``. The default is ``info``. + + * norace - + Disable racy fallback. The default is false. + + * posix_lock|no_posix_lock - + Enable/disable remote POSIX locks. The default is ``posix_lock``. + + * readdirplus|no_readdirplus - + Enable/disable readdirplus. The default is ``readdirplus``. + + * source=PATH - + Share host directory tree located at PATH. This option is required. + + * timeout=TIMEOUT - + I/O timeout in seconds. The default depends on cache= option. + + * writeback|no_writeback - + Enable/disable writeback cache. The cache alows the FUSE client to buffer + and merge write requests. The default is ``no_writeback``. + + * xattr|no_xattr - + Enable/disable extended attributes (xattr) on files and directories. The + default is ``no_xattr``. + +.. option:: --socket-path=PATH + + Listen on vhost-user UNIX domain socket at PATH. + +.. option:: --fd=FDNUM + + Accept connections from vhost-user UNIX domain socket file descriptor FDNUM. + The file descriptor must already be listening for connections. + +.. option:: --thread-pool-size=NUM + + Restrict the number of worker threads per request queue to NUM. The default + is 64. + +.. option:: --cache=none|auto|always + + Select the desired trade-off between coherency and performance. ``none`` + forbids the FUSE client from caching to achieve best coherency at the cost of + performance. ``auto`` acts similar to NFS with a 1 second metadata cache + timeout. ``always`` sets a long cache lifetime at the expense of coherency. + +Examples +-------- + +Export ``/var/lib/fs/vm001/`` on vhost-user UNIX domain socket +``/var/run/vm001-vhost-fs.sock``: + +:: + + 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-memfd,id=mem,size=4G,share=on \ + -numa node,memdev=mem \ + ... + guest# mount -t virtiofs myfs /mnt |