Re: [Qemu-devel] QMP: RFC: I/O error info & query-stop-reason

[Luiz Capitulino <lcapitulino@redhat.com>]

On Tue, 07 Jun 2011 10:39:45 -0500
Anthony Liguori <anthony@codemonkey.ws> wrote:

> On 06/07/2011 09:46 AM, Luiz Capitulino wrote:
> > On Mon, 06 Jun 2011 08:08:51 -0500
> > Anthony Liguori<anthony@codemonkey.ws>  wrote:
> >
> >> On 06/06/2011 04:25 AM, Kevin Wolf wrote:
> >>> Am 02.06.2011 20:09, schrieb Luiz Capitulino:
> >>>>>> I'm ok with either way. But in case you meant the second one, I guess
> >>>>>> we should make "reason" a dictionary so that we can group related
> >>>>>> information when we extend the field, for example:
> >>>>>>
> >>>>>>     "reason": { "no space": false, "no permission": true }
> >>>
> >>> Splitting up enums into a number of booleans looks like a bad idea to
> >>> me. It makes things more verbose than they should be, and even worse, it
> >>> implies that more than one field could be true.
> >>
> >> I agree.  What I had suggested was to not have a reason at all.
> >
> > Is it better if we add a new enum to query-block? Like the "io-error" key we
> > have talked about earlier? Like:
> >
> >   "io-error": "no space"
> 
> 1) enums have to follow some rules.  One obvious rule would be there 
> can't be spaces in the enum value.
> 
> 2) Do we have an defined enum values besides no-space?  If not, let's 
> not artificially add an enum.
> 
> >
> > We could have "no space", "low level" (that's how the man page defines EIO) and
> > "unknown".
> 
> 3) what's the difference between "no space" and "low level"?

The latter means the device doesn't have enough space to write more data,
the former is I/O I guess it's more device specific.

What's your suggestion?