Re: [PATCH v4 20/34] arm: Convert various functions to use ptdescs

On Mon, Jun 12, 2023 at 02:04:09PM -0700, Vishal Moola (Oracle) wrote:
> As part of the conversions to replace pgtable constructor/destructors with
> ptdesc equivalents, convert various page table functions to use ptdescs.
> 
> late_alloc() also uses the __get_free_pages() helper function. Convert
> this to use pagetable_alloc() and ptdesc_address() instead to help
> standardize page tables further.
> 
> Signed-off-by: Vishal Moola (Oracle) <[email protected]>

Acked-by: Mike Rapoport (IBM) <[email protected]>

One comment below.

> ---
>  arch/arm/include/asm/tlb.h | 12 +++++++-----
>  arch/arm/mm/mmu.c          |  6 +++---
>  2 files changed, 10 insertions(+), 8 deletions(-)
> 
> diff --git a/arch/arm/include/asm/tlb.h b/arch/arm/include/asm/tlb.h
> index b8cbe03ad260..f40d06ad5d2a 100644
> --- a/arch/arm/include/asm/tlb.h
> +++ b/arch/arm/include/asm/tlb.h
> @@ -39,7 +39,9 @@ static inline void __tlb_remove_table(void *_table)
>  static inline void
>  __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte, unsigned long addr)
>  {
> -	pgtable_pte_page_dtor(pte);
> +	struct ptdesc *ptdesc = page_ptdesc(pte);
> +
> +	pagetable_pte_dtor(ptdesc);
>  
>  #ifndef CONFIG_ARM_LPAE
>  	/*
> @@ -50,17 +52,17 @@ __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte, unsigned long addr)
>  	__tlb_adjust_range(tlb, addr - PAGE_SIZE, 2 * PAGE_SIZE);
>  #endif
>  
> -	tlb_remove_table(tlb, pte);
> +	tlb_remove_ptdesc(tlb, ptdesc);
>  }
>  
>  static inline void
>  __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp, unsigned long addr)
>  {
>  #ifdef CONFIG_ARM_LPAE
> -	struct page *page = virt_to_page(pmdp);
> +	struct ptdesc *ptdesc = virt_to_ptdesc(pmdp);
>  
> -	pgtable_pmd_page_dtor(page);
> -	tlb_remove_table(tlb, page);
> +	pagetable_pmd_dtor(ptdesc);
> +	tlb_remove_ptdesc(tlb, ptdesc);
>  #endif
>  }
>  
> diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
> index 22292cf3381c..294518fd0240 100644
> --- a/arch/arm/mm/mmu.c
> +++ b/arch/arm/mm/mmu.c
> @@ -737,11 +737,11 @@ static void __init *early_alloc(unsigned long sz)
>  
>  static void *__init late_alloc(unsigned long sz)
>  {
> -	void *ptr = (void *)__get_free_pages(GFP_PGTABLE_KERNEL, get_order(sz));
> +	void *ptdesc = pagetable_alloc(GFP_PGTABLE_KERNEL, get_order(sz));
>  
> -	if (!ptr || !pgtable_pte_page_ctor(virt_to_page(ptr)))
> +	if (!ptdesc || !pagetable_pte_ctor(ptdesc))
>  		BUG();
> -	return ptr;
> +	return ptdesc;

should be

	return  ptdesc_to_virt(ptdesc);

>  }
>  
>  static pte_t * __init arm_pte_alloc(pmd_t *pmd, unsigned long addr,
> -- 
> 2.40.1
> 
> 

-- 
Sincerely yours,
Mike.