From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:47545) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TKCx3-0007uU-Tt for qemu-devel@nongnu.org; Fri, 05 Oct 2012 14:48:47 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TKCx2-0003YR-NH for qemu-devel@nongnu.org; Fri, 05 Oct 2012 14:48:45 -0400 Received: from e9.ny.us.ibm.com ([32.97.182.139]:45709) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TKCx2-0003YJ-IO for qemu-devel@nongnu.org; Fri, 05 Oct 2012 14:48:44 -0400 Received: from /spool/local by e9.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 5 Oct 2012 14:48:43 -0400 Received: from d01av02.pok.ibm.com (d01av02.pok.ibm.com [9.56.224.216]) by d01relay01.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q95ImegG095480 for ; Fri, 5 Oct 2012 14:48:40 -0400 Received: from d01av02.pok.ibm.com (loopback [127.0.0.1]) by d01av02.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q95Imd4f027573 for ; Fri, 5 Oct 2012 15:48:40 -0300 Message-ID: <506F2B87.9000909@linux.vnet.ibm.com> Date: Fri, 05 Oct 2012 14:48:39 -0400 From: Corey Bryant MIME-Version: 1.0 References: <1349460425-30601-1-git-send-email-coreyb@linux.vnet.ibm.com> <1349460425-30601-4-git-send-email-coreyb@linux.vnet.ibm.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 3/4] qemu-config: Add -drive fd and opaque options List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Blue Swirl Cc: libvir-list@redhat.com, kwolf@redhat.com, qemu-devel@nongnu.org On 10/05/2012 02:25 PM, Blue Swirl wrote: > On Fri, Oct 5, 2012 at 6:07 PM, Corey Bryant wrote: >> These new options can be used for passing drive file descriptors >> on the command line, instead of using the file option to specify >> a file name. >> >> These new command line options mirror the existing add-fd QMP >> command which allows an fd to be passed to QEMU via SCM_RIGHTS and >> added to an fd set. The opaque option is also available with >> add-fd, and allows a free-form string to be stored in the fd set >> along with the fd. >> >> Signed-off-by: Corey Bryant >> --- >> qemu-config.c | 8 ++++++++ >> qemu-options.hx | 15 +++++++++++++-- >> 2 files changed, 21 insertions(+), 2 deletions(-) >> >> diff --git a/qemu-config.c b/qemu-config.c >> index cd1ec21..91053dd 100644 >> --- a/qemu-config.c >> +++ b/qemu-config.c >> @@ -114,6 +114,14 @@ static QemuOptsList qemu_drive_opts = { >> .name = "copy-on-read", >> .type = QEMU_OPT_BOOL, >> .help = "copy read data from backing file into image file", >> + },{ >> + .name = "fd", >> + .type = QEMU_OPT_NUMBER, >> + .help = "disk image file descriptor", >> + },{ >> + .name = "opaque", > > 'opaque' is not very descriptive and it's also not obvious (except > from the help text) that it's only interesting for file descriptors. > How about fd_name, fd_tag or fd_descr? > I'd like to mirror the add-fd QMP command as much as possible: { 'command': 'add-fd', 'data': {'*fdset-id': 'int', '*opaque': 'str'}, 'returns': 'AddfdInfo' } And I think use of opaque will make more sense if I don't merge these options in to -drive, and instead create a new command specifically for adding fds, like Eric is suggesting. -- Regards, Corey Bryant >> + .type = QEMU_OPT_STRING, >> + .help = "free-form string used to describe fd", >> }, >> { /* end of list */ } >> }, >> diff --git a/qemu-options.hx b/qemu-options.hx >> index 7d97f96..513530f 100644 >> --- a/qemu-options.hx >> +++ b/qemu-options.hx >> @@ -149,7 +149,7 @@ using @file{/dev/cdrom} as filename (@pxref{host_drives}). >> ETEXI >> >> DEF("drive", HAS_ARG, QEMU_OPTION_drive, >> - "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n" >> + "-drive [file=file|fd=fd[,opaque=o]][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n" >> " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n" >> " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n" >> " [,serial=s][,addr=A][,id=name][,aio=threads|native]\n" >> @@ -170,6 +170,12 @@ this drive. If the filename contains comma, you must double it >> >> Special files such as iSCSI devices can be specified using protocol >> specific URLs. See the section for "Device URL Syntax" for more information. >> +@item fd=@var{fd} >> +This option defines which disk image (@pxref{disk_images}) file descriptor to >> +use with this drive. >> +@item opaque=@var{opaque} >> +This option defines a free-form string that describes @var{fd}. This is used >> +when storing @var{fd} in a file descriptor set. >> @item if=@var{interface} >> This option defines on which type on interface the drive is connected. >> Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio. >> @@ -257,12 +263,17 @@ qemu-system-i386 -drive file=file,index=2,media=disk >> qemu-system-i386 -drive file=file,index=3,media=disk >> @end example >> >> +You can open an image using a pre-opened file descriptor: >> +@example >> +qemu-system-i386 -drive fd=24,opaque="rdwr:/path/to/file",index=0,media=disk >> +@end example >> + >> You can connect a CDROM to the slave of ide0: >> @example >> qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom >> @end example >> >> -If you don't specify the "file=" argument, you define an empty drive: >> +If you don't specify the "file=" or "fd=" arguments, you define an empty drive: >> @example >> qemu-system-i386 -drive if=ide,index=1,media=cdrom >> @end example >> -- >> 1.7.11.4 >> >> >