Re: [PATCH 04/12] m68k: nommu: use pgtable-nopud instead of 4level-fixup

[Greg Ungerer <gerg@linux-m68k.org>]

Hi Mike,

On 24/10/19 3:35 pm, Mike Rapoport wrote:
> Hi Greg,
> 
> On Thu, Oct 24, 2019 at 02:09:01PM +1000, Greg Ungerer wrote:
>> Hi Mike,
>>
>> On 23/10/19 7:28 pm, Mike Rapoport wrote:
>>> From: Mike Rapoport <rppt@linux.ibm.com>
>>>
>>> The generic nommu implementation of page table manipulation takes care of
>>> folding of the upper levels and does not require fixups.
>>>
>>> Simply replace of include/asm-generic/4level-fixup.h with
>>> include/asm-generic/pgtable-nopud.h.
>>>
>>> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
>>> ---
>>>   arch/m68k/include/asm/pgtable_no.h | 2 +-
>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/arch/m68k/include/asm/pgtable_no.h b/arch/m68k/include/asm/pgtable_no.h
>>> index c18165b..ccc4568 100644
>>> --- a/arch/m68k/include/asm/pgtable_no.h
>>> +++ b/arch/m68k/include/asm/pgtable_no.h
>>> @@ -2,7 +2,7 @@
>>>   #ifndef _M68KNOMMU_PGTABLE_H
>>>   #define _M68KNOMMU_PGTABLE_H
>>> -#include <asm-generic/4level-fixup.h>
>>> +#include <asm-generic/pgtable-nopud.h>
>>>   /*
>>>    * (C) Copyright 2000-2002, Greg Ungerer <gerg@snapgear.com>
>>
>> This fails to compile for me (targeting m5208evb_defconfig):
>>
>>    CC      init/main.o
>> In file included from ./arch/m68k/include/asm/pgtable_no.h:56:0,
>>                   from ./arch/m68k/include/asm/pgtable.h:3,
>>                   from ./include/linux/mm.h:99,
>>                   from ./include/linux/ring_buffer.h:5,
>>                   from ./include/linux/trace_events.h:6,
>>                   from ./include/trace/syscall.h:7,
>>                   from ./include/linux/syscalls.h:85,
>>                   from init/main.c:21:
>> ./include/asm-generic/pgtable.h:738:34: error: unknown type name ‘pmd_t’
>>   static inline int pmd_soft_dirty(pmd_t pmd)
>>                                    ^
> 
> ...
> 
>> scripts/Makefile.build:265: recipe for target 'init/main.o' failed
>> make[1]: *** [init/main.o] Error 1
>> Makefile:1649: recipe for target 'init' failed
>> make: *** [init] Error 2
> 
> The hunk below fixes the build.
> 
> diff --git a/arch/m68k/include/asm/page.h b/arch/m68k/include/asm/page.h
> index c00b67a..05e1e1e 100644
> --- a/arch/m68k/include/asm/page.h
> +++ b/arch/m68k/include/asm/page.h
> @@ -21,7 +21,7 @@
>   /*
>    * These are used to make use of C type-checking..
>    */
> -#if CONFIG_PGTABLE_LEVELS == 3
> +#if !defined(CONFIG_MMU) || CONFIG_PGTABLE_LEVELS == 3
>   typedef struct { unsigned long pmd[16]; } pmd_t;
>   #define pmd_val(x)	((&x)->pmd[0])
>   #define __pmd(x)	((pmd_t) { { (x) }, })

That looks better. Thanks.
Tested and working on m68knommu. For the combined patches:

Acked-by: Greg Ungerer <gerg@linux-m68k.org>

Regards
Greg