[PATCH v1 4/7] arm64/pgtable: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE

[David Hildenbrand]

On 18.03.22 12:33, Catalin Marinas wrote:
> On Fri, Mar 18, 2022 at 10:59:10AM +0100, David Hildenbrand wrote:
>> diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h
>> index b1e1b74d993c..fd6ddf14c190 100644
>> --- a/arch/arm64/include/asm/pgtable-prot.h
>> +++ b/arch/arm64/include/asm/pgtable-prot.h
>> @@ -14,6 +14,7 @@
>>   * Software defined PTE bits definition.
>>   */
>>  #define PTE_WRITE		(PTE_DBM)		 /* same as DBM (51) */
>> +#define PTE_SWP_EXCLUSIVE	(PTE_TABLE_BIT)		 /* only for swp ptes */
>>  #define PTE_DIRTY		(_AT(pteval_t, 1) << 55)
>>  #define PTE_SPECIAL		(_AT(pteval_t, 1) << 56)
>>  #define PTE_DEVMAP		(_AT(pteval_t, 1) << 57)
>> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
>> index 94e147e5456c..c78994073cd0 100644
>> --- a/arch/arm64/include/asm/pgtable.h
>> +++ b/arch/arm64/include/asm/pgtable.h
>> @@ -402,6 +402,22 @@ static inline pgprot_t mk_pmd_sect_prot(pgprot_t prot)
>>  	return __pgprot((pgprot_val(prot) & ~PMD_TABLE_BIT) | PMD_TYPE_SECT);
>>  }
>>  
>> +#define __HAVE_ARCH_PTE_SWP_EXCLUSIVE
>> +static inline pte_t pte_swp_mkexclusive(pte_t pte)
>> +{
>> +	return set_pte_bit(pte, __pgprot(PTE_SWP_EXCLUSIVE));
>> +}
>> +
>> +static inline int pte_swp_exclusive(pte_t pte)
>> +{
>> +	return pte_val(pte) & PTE_SWP_EXCLUSIVE;
>> +}
>> +
>> +static inline pte_t pte_swp_clear_exclusive(pte_t pte)
>> +{
>> +	return clear_pte_bit(pte, __pgprot(PTE_SWP_EXCLUSIVE));
>> +}
>> +
>>  #ifdef CONFIG_NUMA_BALANCING
>>  /*
>>   * See the comment in include/linux/pgtable.h
>> @@ -908,7 +924,8 @@ static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
>>  
>>  /*
>>   * Encode and decode a swap entry:
>> - *	bits 0-1:	present (must be zero)
>> + *	bits 0:		present (must be zero)
>> + *	bits 1:		remember PG_anon_exclusive
> 
> It looks fine to me.
> 
> Reviewed-by: Catalin Marinas <catalin.marinas at arm.com>
> 

Great, thanks!

-- 
Thanks,

David / dhildenb