Re: [PATCH] xen/grant-table: Avoid m2p_override during mapping

[Zoltan Kiss <zoltan.kiss@citrix.com>]

On 13/01/14 10:18, Roger Pau Monné wrote:
>> @@ -958,26 +942,14 @@ int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops,
>>   			set_phys_to_machine(unmap_ops[i].host_addr >> PAGE_SHIFT,
>>   					INVALID_P2M_ENTRY);
>>   		}
>> -		return ret;
>> -	}
>> -
>> -	if (!in_interrupt() && paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) {
>> -		arch_enter_lazy_mmu_mode();
>> -		lazy = true;
>> -	}
>> -
>> -	for (i = 0; i < count; i++) {
>> -		ret = m2p_remove_override(pages[i], kmap_ops ?
>> -				       &kmap_ops[i] : NULL);
>> -		if (ret)
>> -			goto out;
>> +	} else {
>> +		for (i = 0; i < count; i++) {
>> +				set_phys_to_machine(page_to_pfn(pages[i]),
>> +						    pages[i]->index);
>
> You seem to relay on page->index containing the old mfn, but I don't see
> it being set on gnttab_map_refs (it's only set on m2p_add_override
> AFAICT), maybe I'm missing something?
>
> Roger.
>

Indeed, I'll fix that, and I will also cut the function prototype update 
out into a separate patch for better readability.

Zoli