[PATCHv3 1/2] arm64: Introduce {set,clear}_pte_bit

[Will Deacon]

On Wed, Aug 13, 2014 at 12:37:46AM +0100, Laura Abbott wrote:
> It's useful to be able to change individual bits in ptes at times.
> Introduce functions for this and update existing pte_mk* functions
> to use these primatives.
> 
> Signed-off-by: Laura Abbott <lauraa at codeaurora.org>
> ---
>  arch/arm64/include/asm/pgtable.h | 33 +++++++++++++++++++--------------
>  1 file changed, 19 insertions(+), 14 deletions(-)

Looks fine to me:

  Acked-by: Will Deacon <will.deacon at arm.com>

Will

> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
> index ffe1ba0..ca41449 100644
> --- a/arch/arm64/include/asm/pgtable.h
> +++ b/arch/arm64/include/asm/pgtable.h
> @@ -149,46 +149,51 @@ extern struct page *empty_zero_page;
>  #define pte_valid_not_user(pte) \
>  	((pte_val(pte) & (PTE_VALID | PTE_USER)) == PTE_VALID)
>  
> -static inline pte_t pte_wrprotect(pte_t pte)
> +static pte_t clear_pte_bit(pte_t pte, pgprot_t prot)
>  {
> -	pte_val(pte) &= ~PTE_WRITE;
> +	pte_val(pte) &= ~pgprot_val(prot);
>  	return pte;
>  }
>  
> -static inline pte_t pte_mkwrite(pte_t pte)
> +static pte_t set_pte_bit(pte_t pte, pgprot_t prot)
>  {
> -	pte_val(pte) |= PTE_WRITE;
> +	pte_val(pte) |= pgprot_val(prot);
>  	return pte;
>  }
>  
> +static inline pte_t pte_wrprotect(pte_t pte)
> +{
> +	return clear_pte_bit(pte, __pgprot(PTE_WRITE));
> +}
> +
> +static inline pte_t pte_mkwrite(pte_t pte)
> +{
> +	return set_pte_bit(pte, __pgprot(PTE_WRITE));
> +}
> +
>  static inline pte_t pte_mkclean(pte_t pte)
>  {
> -	pte_val(pte) &= ~PTE_DIRTY;
> -	return pte;
> +	return clear_pte_bit(pte, __pgprot(PTE_DIRTY));
>  }
>  
>  static inline pte_t pte_mkdirty(pte_t pte)
>  {
> -	pte_val(pte) |= PTE_DIRTY;
> -	return pte;
> +	return set_pte_bit(pte, __pgprot(PTE_DIRTY));
>  }
>  
>  static inline pte_t pte_mkold(pte_t pte)
>  {
> -	pte_val(pte) &= ~PTE_AF;
> -	return pte;
> +	return clear_pte_bit(pte, __pgprot(PTE_AF));
>  }
>  
>  static inline pte_t pte_mkyoung(pte_t pte)
>  {
> -	pte_val(pte) |= PTE_AF;
> -	return pte;
> +	return set_pte_bit(pte, __pgprot(PTE_AF));
>  }
>  
>  static inline pte_t pte_mkspecial(pte_t pte)
>  {
> -	pte_val(pte) |= PTE_SPECIAL;
> -	return pte;
> +	return set_pte_bit(pte, __pgprot(PTE_SPECIAL));
>  }
>  
>  static inline void set_pte(pte_t *ptep, pte_t pte)
> -- 
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> hosted by The Linux Foundation
> 
>