[PATCH v5 1/4] resource: Move reparent_resources() to kernel/resource.c and make it public

[Andy Shevchenko]

On Tue, Jun 12, 2018 at 12:38 PM, Baoquan He <bhe at redhat.com> wrote:
> On 06/12/18 at 11:29am, Andy Shevchenko wrote:
>> On Tue, Jun 12, 2018 at 6:28 AM, Baoquan He <bhe at redhat.com> wrote:

>> > +{
>>
>> > +       for (pp = &parent->child; (p = *pp) != NULL; pp = &p->sibling) {
>> > +               if (p->end < res->start)
>> > +                       continue;
>> > +               if (res->end < p->start)
>> > +                       break;
>>
>> > +               if (p->start < res->start || p->end > res->end)
>> > +                       return -1;      /* not completely contained */
>>
>> Usually we are expecting real eeror codes.
>
> Hmm, I just copied it from arch/powerpc/kernel/pci-common.c. The
> function interface expects an integer returned value, not sure what a
> real error codes look like, could you give more hints? Will change
> accordingly.

I briefly looked at the code and error codes we have, so, my proposal
is one of the following
 - use -ECANCELED (not the best choice for first occurrence here,
though I can't find better)
 - use positive integers (or enum), like
  #define RES_REPARENTED 0
  #define RES_OVERLAPPED 1
  #define RES_NOCONFLICT 2


>> > +               if (firstpp == NULL)
>> > +                       firstpp = pp;
>> > +       }
>>
>> > +       if (firstpp == NULL)
>> > +               return -1;      /* didn't find any conflicting entries? */
>>
>> Ditto.

Ditto.

>>
>> > +}
>> > +EXPORT_SYMBOL(reparent_resources);

-- 
With Best Regards,
Andy Shevchenko