Re: [PATCH V5 7/7] mm/mmap: Drop arch_vm_get_page_pgprot()

[Anshuman Khandual <anshuman.khandual@arm.com>]

On 4/12/22 18:00, Christophe Leroy wrote:
> 
> 
> Le 12/04/2022 à 06:38, Anshuman Khandual a écrit :
>> There are no platforms left which use arch_vm_get_page_prot(). Just drop
>> generic arch_vm_get_page_prot().
>>
>> Cc: Andrew Morton <akpm@linux-foundation.org>
>> Cc: linux-mm@kvack.org
>> Cc: linux-kernel@vger.kernel.org
>> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
>> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
>> ---
>>   include/linux/mman.h | 4 ----
>>   mm/mmap.c            | 3 +--
>>   2 files changed, 1 insertion(+), 6 deletions(-)
>>
>> diff --git a/include/linux/mman.h b/include/linux/mman.h
>> index b66e91b8176c..58b3abd457a3 100644
>> --- a/include/linux/mman.h
>> +++ b/include/linux/mman.h
>> @@ -93,10 +93,6 @@ static inline void vm_unacct_memory(long pages)
>>   #define arch_calc_vm_flag_bits(flags) 0
>>   #endif
>>   
>> -#ifndef arch_vm_get_page_prot
>> -#define arch_vm_get_page_prot(vm_flags) __pgprot(0)
>> -#endif
>> -
>>   #ifndef arch_validate_prot
>>   /*
>>    * This is called from mprotect().  PROT_GROWSDOWN and PROT_GROWSUP have
>> diff --git a/mm/mmap.c b/mm/mmap.c
>> index edf2a5e38f4d..db7f33154206 100644
>> --- a/mm/mmap.c
>> +++ b/mm/mmap.c
>> @@ -110,8 +110,7 @@ pgprot_t protection_map[16] __ro_after_init = {
>>   pgprot_t vm_get_page_prot(unsigned long vm_flags)
>>   {
>>   	pgprot_t ret = __pgprot(pgprot_val(protection_map[vm_flags &
>> -				(VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]) |
>> -			pgprot_val(arch_vm_get_page_prot(vm_flags)));
>> +				(VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]));
>>   
>>   	return ret;
>>   }
> 
> __pgprot(pgprot_val(x)) is a no-op.
> 
> You can simply do:
> 
> 	return protection_map[vm_flags &
> 		(VM_READ|VM_WRITE|VM_EXEC|VM_SHARED);

Sure, will do.