Re: [Qemu-devel] [PATCH V6 8/8] block: Use graph node name as reference in bdrv_file_open().

["Benoît Canet" <benoit.canet@irqsave.net>]

Le Friday 24 Jan 2014 à 15:54:39 (+0100), Max Reitz a écrit :
> On 24.01.2014 15:48, Kevin Wolf wrote:
> >Am 24.01.2014 um 14:37 hat Max Reitz geschrieben:
> >>On 24.01.2014 14:26, Kevin Wolf wrote:
> >>>Am 23.01.2014 um 21:31 hat Benoît Canet geschrieben:
> >>>>Signed-off-by: Benoit Canet <benoit@irqsave.net>
> >>>>---
> >>>>  block.c | 6 +++---
> >>>>  1 file changed, 3 insertions(+), 3 deletions(-)
> >>>I'm not going to merge this one yet. It breaks qemu-iotests case 071,
> >>>which would have to be adapted.
> >>>
> >>>However, first of all I'd like to hear the opinions of at least Eric and
> >>>Max on what BlockRef should really refer to. I think node names make
> >>>most sense, but perhaps it's a bit inconvenient and the command line
> >>>should default to node-name = id when id is set, but node-name isn't?
> >>The QAPI schema is pretty clear about this: “references the ID of an
> >>existing block device.”
> >Sure, that's because I wrote that text before we had a node name.
> >
> >However, in 1.7 references didn't work yet, so we still have all freedom
> >to change the interface as we like.
> 
> Yes, that's right.
> 
> >>However, if the ID cannot be found, I think
> >>we should interpret it as a reference to the node name.
> >>
> >>Therefore, I'd first try bdrv_find() and if that returns NULL, try
> >>again with bdrv_find_node().
> >I think I would prefer to avoid such ambiguities. Otherwise a management
> >tool that wants to use the node name needs to check first if it's not
> >already used as a device name somewhere else and would therefore operate
> >on the wrong device.
> >
> >On the other hand, a management tool using the same names for devices
> >and nodes just gets what it deserves.
> >
> >Perhaps we should use a common namespace for both, i.e. you get an error
> >if you try to assign a node name that is already a device name and vice
> >versa?
> 
> This is what I would go for. However, then I don't really know why
> we should separate the ID and the node name in the first place
> (although that's probably because I haven't followed the discussion
> around node names).
> 
> Max

Ping,

I still want to make quorum merge.
What should be done for the references ?

Best regards

Benoît