Message ID | 20200121122433.50803-94-dgilbert@redhat.com |
---|---|
State | New |
Headers | show |
Series | virtiofs daemon [all] | expand |
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 >
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