Messages in this thread | | | Date | Mon, 13 Jan 2014 13:58:22 +0000 | From | "Jan Beulich" <> | Subject | Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard |
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>>> On 13.01.14 at 14:45, David Vrabel <david.vrabel@citrix.com> wrote: > On 13/01/14 13:16, Jan Beulich wrote: >>>>> On 13.01.14 at 14:00, Ian Campbell <Ian.Campbell@citrix.com> wrote: >>> On Mon, 2014-01-13 at 12:34 +0000, Jan Beulich wrote: >>>>>>> On 13.01.14 at 13:01, Olaf Hering <olaf@aepfle.de> wrote: >>>>> On Mon, Jan 13, Jan Beulich wrote: >>>>> >>>>>> You can't do this in one go - the first two and the last one may be >>>>>> set independently (and are independent in their meaning), and >>>>>> hence need to be queried independently (xenbus_gather() fails >>>>>> on the first absent value). >>>>> >>>>> Yes, thats the purpose. Since the properties are required its an all or >>>>> nothing thing. If they are truly optional then blkif.h should be updated >>>>> to say that. >>>> >>>> They _are_ optional. >>> >>> But is it true that either they are all present or they are all absent? >> >> No, it's not. discard-secure is independent of the other two (but >> those other two are tied together). > > Can we have a patch to blkif.h that clarifies this? > > e.g., > > feature-discard > > ... > > discard-granularity and discard-offset must also be present if > feature-discard is enabled
It would be "may" here too afaict. But I'll defer to Konrad, who has done more work in this area...
Jan
> discard-secure may also be present if feature-discard is enabled. > > David
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