Re: [PATCH] NOMMU: add support for Memory Protection Units (MPU)

[Mike Frysinger <vapier.adi@gmail.com>]

On Tue, Jul 14, 2009 at 12:14, Johannes Weiner wrote:
> On Tue, Jul 14, 2009 at 10:22:20AM -0400, Mike Frysinger wrote:
>> --- a/mm/nommu.c
>> +++ b/mm/nommu.c
>> @@ -640,11 +641,23 @@ static void add_vma_to_mm(struct mm_struct *mm, struct vm_area_struct *vma)
>>       struct vm_area_struct *pvma, **pp;
>>       struct address_space *mapping;
>>       struct rb_node **p, *parent;
>> +#ifdef CONFIG_MPU
>> +     long start;
>> +#endif
>>
>>       kenter(",%p", vma);
>>
>>       BUG_ON(!vma->vm_region);
>>
>> +#ifdef CONFIG_MPU
>> +     start = vma->vm_start & PAGE_MASK;
>> +     while (start < vma->vm_end) {
>> +             protect_page(mm, start, vma->vm_flags);
>> +             start += PAGE_SIZE;
>> +     }
>> +     update_protections(mm);
>> +#endif
>> +
>>       mm->map_count++;
>>       vma->vm_mm = mm;
>>
>> @@ -707,9 +720,21 @@ static void delete_vma_from_mm(struct vm_area_struct *vma)
>>       struct vm_area_struct **pp;
>>       struct address_space *mapping;
>>       struct mm_struct *mm = vma->vm_mm;
>> +#ifdef CONFIG_MPU
>> +     long start;
>> +#endif
>>
>>       kenter("%p", vma);
>>
>> +#ifdef CONFIG_MPU
>> +     start = vma->vm_start & PAGE_MASK;
>> +     while (start < vma->vm_end) {
>> +             protect_page(mm, start, 0);
>> +             start += PAGE_SIZE;
>> +     }
>> +     update_protections(mm);
>> +#endif
>
> How about refactoring that into one function?  Saves all but one
> #ifdef.

makes sense to me, thanks
-mike