Re: [Qemu-devel] [PATCH] block: Expose host_* drivers in blockdev-add

[Markus Armbruster]

Kevin Wolf <address@hidden> writes:

> Am 23.04.2014 um 17:34 hat Eric Blake geschrieben:
>> On 04/23/2014 09:12 AM, Kevin Wolf wrote:
>> > All the functionality to use the host_device, host_cdrom and host_floppy
>> > drivers is already there, they just need to be added to the schema.
>> > 
>> > Signed-off-by: Kevin Wolf <address@hidden>
>> > ---
>> >  qapi-schema.json | 6 +++++-
>> >  1 file changed, 5 insertions(+), 1 deletion(-)
>> > 
>> > diff --git a/qapi-schema.json b/qapi-schema.json
>> > index 391356f..0fc0f12 100644
>> > --- a/qapi-schema.json
>> > +++ b/qapi-schema.json
>> > @@ -4288,7 +4288,8 @@
>> >  # Since: 2.0
>> 
>> We haven't been good at tracking enum growth, but it can't hurt to try.
>>  It might be worth changing this line to read:
>> 
>> # Since: 2.0, 'host_device', 'host_cdrom', 'host_floppy' since 2.1
>
> I'm fine with documenting the changes, but this format doesn't look like
> it works very well in the long term.
>
>> >  ##
>> >  { 'enum': 'BlockdevDriver',
>> > - 'data': [ 'file', 'http', 'https', 'ftp', 'ftps', 'tftp',
>> > vvfat', 'blkdebug',
>> > +  'data': [ 'file', 'host_device', 'host_cdrom', 'host_floppy',
>> 
>> Any reason you used _ instead of - in these names?  Newer QMP tends to
>> prefer - unless there is a good reason why _ has already been baked in
>> due to back-compat.
>
> The block driver has always been called host_device with an underscore.
> We can't change it because that would break compatibility on the command
> line.

A simple indirection could buy us a little more consistency in QMP.  If
you say that's not worth the trouble because there's so much
inconsistency already, you have a point.  I still hate it, though :)

Probably the only way to stop the proliferation of this '-' vs. '_'
nuisance is to accept both '-' and '_' everywhere in QMP, and use only
'-' in documentation.  Clearly beyond the scope of your patch.