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

On Tue, Jun 12, 2018 at 5:20 PM, Andy Shevchenko
[off-list ref] wrote:

On Tue, Jun 12, 2018 at 12:38 PM, Baoquan He [off-list ref] wrote:

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On 06/12/18 at 11:29am, Andy Shevchenko wrote:

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On Tue, Jun 12, 2018 at 6:28 AM, Baoquan He [off-list ref] wrote:

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+{

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+       for (pp = &parent->child; (p = *pp) != NULL; pp = &p->sibling) {
+               if (p->end < res->start)
+                       continue;
+               if (res->end < p->start)
+                       break;

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+               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)

Actually -ENOTSUPP might suit the first case (although the actual
would be something like -EOVERLAP, which we don't have)

 - use positive integers (or enum), like
  #define RES_REPARENTED 0
  #define RES_OVERLAPPED 1
  #define RES_NOCONFLICT 2

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+               if (firstpp == NULL)
+                       firstpp = pp;
+       }

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

Ditto.

Ditto.

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+}
+EXPORT_SYMBOL(reparent_resources);

--
With Best Regards,
Andy Shevchenko

-- 
With Best Regards,
Andy Shevchenko