From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 11DE0C282DD for ; Thu, 9 Jan 2020 20:03:13 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CE7A12072A for ; Thu, 9 Jan 2020 20:03:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="OercfJqt" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CE7A12072A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:36802 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ipe1P-0001Va-Tm for qemu-devel@archiver.kernel.org; Thu, 09 Jan 2020 15:03:11 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:44238) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ipe0i-00013p-JE for qemu-devel@nongnu.org; Thu, 09 Jan 2020 15:02:31 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ipe0f-00029h-6x for qemu-devel@nongnu.org; Thu, 09 Jan 2020 15:02:26 -0500 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:38640 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ipe0e-00021n-V7 for qemu-devel@nongnu.org; Thu, 09 Jan 2020 15:02:25 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1578600143; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=B1TIemGUGuraqVgdzQs9QWNpoHdJWbTkUHzVZwlo48A=; b=OercfJqtArnCA2BuDIoWG7R/b+dkE16HVkUcPc9KjUPv6eU4+V45Yq9PV4DJUDurEaycpD tKTW7aTx7xUlt793bAt/jYqJLJ5Whg4hDJyjQqNKFv/VcKx06QFIekYTpK2jT8X3MbOVka 7W4PoIYOMrUgZ+BidlxQvJSVdQYlh4s= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-194-WS3TxLN8OP-kn3NoFsaaIw-1; Thu, 09 Jan 2020 15:02:20 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D7AFE107ACC4 for ; Thu, 9 Jan 2020 20:02:19 +0000 (UTC) Received: from work-vm (unknown [10.36.118.29]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 59C1F620A6; Thu, 9 Jan 2020 20:02:16 +0000 (UTC) Date: Thu, 9 Jan 2020 20:02:13 +0000 From: "Dr. David Alan Gilbert" To: Daniel =?iso-8859-1?Q?P=2E_Berrang=E9?= Subject: Re: [PATCH 092/104] virtiofsd: add man page Message-ID: <20200109200213.GT6795@work-vm> References: <20191212163904.159893-1-dgilbert@redhat.com> <20191212163904.159893-93-dgilbert@redhat.com> <20200107121328.GD3368802@redhat.com> MIME-Version: 1.0 In-Reply-To: <20200107121328.GD3368802@redhat.com> User-Agent: Mutt/1.13.0 (2019-11-30) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: WS3TxLN8OP-kn3NoFsaaIw-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 205.139.110.120 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-devel@nongnu.org, stefanha@redhat.com, vgoyal@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Daniel P. Berrang=E9 (berrange@redhat.com) wrote: > On Thu, Dec 12, 2019 at 04:38:52PM +0000, Dr. David Alan Gilbert (git) wr= ote: > > From: Stefan Hajnoczi > >=20 > > Signed-off-by: Stefan Hajnoczi > > --- > > Makefile | 7 +++ > > tools/virtiofsd/virtiofsd.texi | 85 ++++++++++++++++++++++++++++++++++ > > 2 files changed, 92 insertions(+) > > create mode 100644 tools/virtiofsd/virtiofsd.texi >=20 > Reviewed-by: Daniel P. Berrang=E9 Thanks. > with some notes at the very end > > +@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. >=20 > 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 w= ill > > +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 f= ile > > +system objects that might lead to files outside the shared directory. = The > > +program also sandboxes itself using seccomp(2) to prevent ptrace(2) an= d other > > +vectors that could allow an attacker to compromise the system after ga= ining > > +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=3D@var{level} > > +Print only log messages matching @var{level} or more severe. @var{lev= el} is > > +one of @code{err}, @code{warn}, @code{info}, or @code{debug}. The def= ault is > > +@var{info}. > > +@item -o source=3D@var{path} > > +Share host directory tree located at @var{path}. This option is requi= red. > > +@item --socket-path=3D@var{path}, -o vhost_user_socket=3D@var{path} > > +Listen on vhost-user UNIX domain socket at @var{path}. > > +@item --fd=3D@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=3D@var{num} > > +Restrict the number of worker threads per request queue to @var{num}. = The default is 64. > > +@item --cache=3D@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 c= oherency. > > +@item --writeback > > +Enable writeback cache, allowing the FUSE client to buffer and merge w= rite requests. > > +@end table > > +@c man end > > + > > +@c man begin EXAMPLES > > +Export @code{/var/lib/fs/vm001/} on vhost-user UNIX domain socket @cod= e{/var/run/vm001-vhost-fs.sock}: > > + > > +@example > > +host# virtiofsd --socket-path=3D/var/run/vm001-vhost-fs.sock -o source= =3D/var/lib/fs/vm001 > > +host# qemu-system-x86_64 \ > > + -chardev socket,id=3Dchar0,path=3D/var/run/vm001-vhost-fs.sock \ > > + -device vhost-user-fs-pci,chardev=3Dchar0,tag=3Dmyfs \ > > + -object memory-backend-file,id=3Dmem,size=3D4G,mem-path=3D/dev/shm= ,share=3Don \ > > + -numa node,memdev=3Dmem \ > > + ... > > +guest# mount -t virtio_fs \ > > + -o default_permissions,allow_other,user_id=3D0,group_id=3D0,rootmo= de=3D040000,dax \ > > + myfs /mnt > > +@end example > > +@c man end > > + > > +@ignore > > +@setfilename virtiofsd > > +@settitle QEMU virtio-fs shared file system daemon > > + > > +@c man begin AUTHOR >=20 > s/AUTHOR/COPYRIGHT/ OK > since this isn't providing any author information. >=20 > > +Copyright (C) 2019 Red Hat, Inc. >=20 > 2019-2020 ! Time flies... > And now insert >=20 > @c man end > @c man begin LICENSE >=20 > > +This is free software; see the source for copying conditions. There i= s NO > > +warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PUR= POSE. > > +@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 >=20 >=20 >=20 > Regards, > Daniel > --=20 > |: https://berrange.com -o- https://www.flickr.com/photos/dberran= ge :| > |: https://libvirt.org -o- https://fstop138.berrange.c= om :| > |: https://entangle-photo.org -o- https://www.instagram.com/dberran= ge :| -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK