Re: [PATCH v3 1/3] ioremap: Update pgtable free interfaces with addr

[Kani, Toshi]

On Mon, 2018-03-19 at 18:10 +0530, Chintan Pandya wrote:
> This patch ("mm/vmalloc: Add interfaces to free unmapped
> page table") adds following 2 interfaces to free the page
> table in case we implement huge mapping.
> 
> pud_free_pmd_page() and pmd_free_pte_page()
> 
> Some architectures (like arm64) needs to do proper TLB
> maintanance after updating pagetable entry even in map.
> Why ? Read this,
> https://patchwork.kernel.org/patch/10134581/
> 
> Pass 'addr' in these interfaces so that proper TLB ops
> can be performed.
> 
> Signed-off-by: Chintan Pandya <cpandya@xxxxxxxxxxxxxx>
 :
> diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
> index 34cda7e..20b0322 100644
> --- a/arch/x86/mm/pgtable.c
> +++ b/arch/x86/mm/pgtable.c
> @@ -710,7 +710,7 @@ int pmd_clear_huge(pmd_t *pmd)
>   * Context: The pud range has been unmaped and TLB purged.
>   * Return: 1 if clearing the entry succeeded. 0 otherwise.
>   */
> -int pud_free_pmd_page(pud_t *pud)
> +int pud_free_pmd_page(pud_t *pud, unsigned long addr)

Please update the function header as well.  Same for pmd.

+ * @addr: Virtual address associated with pud.

--- a/include/asm-generic/pgtable.h
> +++ b/include/asm-generic/pgtable.h
> @@ -983,8 +983,8 @@ static inline int p4d_clear_huge(p4d_t *p4d)
>  int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot);
>  int pud_clear_huge(pud_t *pud);
>  int pmd_clear_huge(pmd_t *pmd);
> -int pud_free_pmd_page(pud_t *pud);
> -int pmd_free_pte_page(pmd_t *pmd);
> +int pud_free_pmd_page(pud_t *pud, unsigned long addr);
> +int pmd_free_pte_page(pmd_t *pmd, unsigned long addr);
>  #else	/* !CONFIG_HAVE_ARCH_HUGE_VMAP */
>  static inline int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t
prot)
>  {
> @@ -1010,11 +1010,11 @@ static inline int pmd_clear_huge(pmd_t *pmd)
>  {
>  	return 0;
>  }
> -static inline int pud_free_pmd_page(pud_t *pud)
> +static inline int pud_free_pmd_page(pud_t *pud, unsigned long addr)
>  {
>  	return 0;
>  }
> -static inline int pmd_free_pte_page(pud_t *pmd)
> +static inline int pmd_free_pte_page(pud_t *pmd, unsigned long addr)

Please base your patches on top of the mm tree or at least pick up
8cab93de994f6 in the mm tree.  Andrew fixed the typo; the 'pud_t' above
should have been 'pmd_t'.

Thanks,
-Toshi