Re: [virtio-comment] comment on pci section

[Rusty Russell <rusty@au1.ibm.com>]

Cornelia Huck <cornelia.huck@de.ibm.com> writes:
> On Wed, 05 Feb 2014 09:49:18 +1030
> Rusty Russell <rusty@au1.ibm.com> wrote:
>
>> +Once the driver has set the DRIVER_OK status bit, all the configured virtqueue of the device are considered live.  All of a device's virtqueues are no longer live once the device has been reset.
>
> What about something similar to my earlier suggestions?
>
> "Once the driver has set the DRIVER_OK status bit, all of the
> configured virtqueues of the device are considered live.  Any of the
> virtqueues of a device are no longer live once the device has been
> reset."

We're really getting down to subtleties of language at this point :)
I don't really mind, but:

"Any of" has suggestions that it means a subset of.  "All of" indicates
the complete set.  Maybe it's better to reverse the sentence?

        None of the virtqueues of a device are live once the device has
        been reset.

>> +A driver MUST NOT alter descriptor table entries which have been
>> +exposed in the available ring (and not marked consumed by the device
>> +in the used ring) of a live virtqueue.
>> +
>> +A driver MUST NOT decrement the available index on a live virtqueue (ie.
>> +do not try to "unexpose" buffers).
>
> "(i.e. the driver MUST NOT try to "unexpose" buffers)."
>
> ?

It's parenthetical to explain motivation, rather than an additional
requirement (the "MUST NOT decrement" is the requirement).  Perhaps it's
clearer if we say:

   A driver MUST NOT decrement the available index on a live virtqueue (ie.
   there is no way to "unexpose" buffers).

?

Cheers,
Rusty.