[PATCH v2 03/17] arm64: Make page table helpers reusable
Julien Grall
julien.grall at arm.com
Thu Apr 26 03:54:55 PDT 2018
Hi Suzuki,
On 27/03/18 14:15, Suzuki K Poulose wrote:
> This patch rearranges the page table level helpers so that it can
> be reused for a page table with different number of levels
> (e.g, stage2 page table for a VM) than the kernel page tables.
> As such there is no functional change with this patch.
>
> The page table helpers are defined to do the right thing for the
> fixed page table levels set for the kernel. This patch tries to
> refactor the code such that, we can have helpers for each level,
> which should be used when the caller knows that the level exists
> for the page table dealt with. Since the kernel defines helpers
> p.d_action and __p.d_action, for consistency, we name the raw
> page table action helpers __raw_p.d_action.
>
> Cc: Catalin Marinas <catalin.marinas at arm.com>
> Cc: Mark Rutland <mark.rutland at arm.com>
> Cc: Will Deacon <will.deacon at arm.com>
> Cc: Steve Capper <steve.capper at arm.com>
> Cc: Marc Zyngier <marc.zyngier at arm.com>
> Cc: Christoffer Dall <cdall at kernel.org>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose at arm.com>
Reviewed-by: Julien Grall <julien.grall at arm.com>
Cheers,
> ---
> arch/arm64/include/asm/pgalloc.h | 34 +++++++++++++++++++----
> arch/arm64/include/asm/pgtable.h | 60 +++++++++++++++++++++++++---------------
> 2 files changed, 66 insertions(+), 28 deletions(-)
>
> diff --git a/arch/arm64/include/asm/pgalloc.h b/arch/arm64/include/asm/pgalloc.h
> index 2e05bcd..ab4662c 100644
> --- a/arch/arm64/include/asm/pgalloc.h
> +++ b/arch/arm64/include/asm/pgalloc.h
> @@ -29,6 +29,30 @@
> #define PGALLOC_GFP (GFP_KERNEL | __GFP_ZERO)
> #define PGD_SIZE (PTRS_PER_PGD * sizeof(pgd_t))
>
> +static inline void __raw_pmd_free(pmd_t *pmdp)
> +{
> + BUG_ON((unsigned long)pmdp & (PAGE_SIZE-1));
> + free_page((unsigned long)pmdp);
> +}
> +
> +static inline void
> +__raw_pud_populate(pud_t *pudp, phys_addr_t pmdp, pudval_t prot)
> +{
> + __raw_set_pud(pudp, __pud(__phys_to_pud_val(pmdp) | prot));
> +}
> +
> +static inline void __raw_pud_free(pud_t *pudp)
> +{
> + BUG_ON((unsigned long)pudp & (PAGE_SIZE-1));
> + free_page((unsigned long)pudp);
> +}
> +
> +static inline void
> +__raw_pgd_populate(pgd_t *pgdp, phys_addr_t pudp, pgdval_t prot)
> +{
> + __raw_set_pgd(pgdp, __pgd(__phys_to_pgd_val(pudp) | prot));
> +}
> +
> #if CONFIG_PGTABLE_LEVELS > 2
>
> static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
> @@ -38,13 +62,12 @@ static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
>
> static inline void pmd_free(struct mm_struct *mm, pmd_t *pmdp)
> {
> - BUG_ON((unsigned long)pmdp & (PAGE_SIZE-1));
> - free_page((unsigned long)pmdp);
> + __raw_pmd_free(pmdp);
> }
>
> static inline void __pud_populate(pud_t *pudp, phys_addr_t pmdp, pudval_t prot)
> {
> - set_pud(pudp, __pud(__phys_to_pud_val(pmdp) | prot));
> + __raw_pud_populate(pudp, pmdp, prot);
> }
>
> static inline void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmdp)
> @@ -67,13 +90,12 @@ static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
>
> static inline void pud_free(struct mm_struct *mm, pud_t *pudp)
> {
> - BUG_ON((unsigned long)pudp & (PAGE_SIZE-1));
> - free_page((unsigned long)pudp);
> + __raw_pud_free(pudp);
> }
>
> static inline void __pgd_populate(pgd_t *pgdp, phys_addr_t pudp, pgdval_t prot)
> {
> - set_pgd(pgdp, __pgd(__phys_to_pgd_val(pudp) | prot));
> + __raw_pgd_populate(pgdp, pudp, prot);
> }
>
> static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgdp, pud_t *pudp)
> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
> index 7e2c27e..5e22503 100644
> --- a/arch/arm64/include/asm/pgtable.h
> +++ b/arch/arm64/include/asm/pgtable.h
> @@ -475,31 +475,39 @@ static inline phys_addr_t pmd_page_paddr(pmd_t pmd)
> */
> #define mk_pte(page,prot) pfn_pte(page_to_pfn(page),prot)
>
> -#if CONFIG_PGTABLE_LEVELS > 2
> +#define __raw_pud_none(pud) (!pud_val(pud))
> +#define __raw_pud_bad(pud) (!(pud_val(pud) & PUD_TABLE_BIT))
> +#define __raw_pud_present(pud) pte_present(pud_pte(pud))
>
> -#define pmd_ERROR(pmd) __pmd_error(__FILE__, __LINE__, pmd_val(pmd))
> -
> -#define pud_none(pud) (!pud_val(pud))
> -#define pud_bad(pud) (!(pud_val(pud) & PUD_TABLE_BIT))
> -#define pud_present(pud) pte_present(pud_pte(pud))
> -
> -static inline void set_pud(pud_t *pudp, pud_t pud)
> +static inline void __raw_set_pud(pud_t *pudp, pud_t pud)
> {
> WRITE_ONCE(*pudp, pud);
> dsb(ishst);
> isb();
> }
>
> -static inline void pud_clear(pud_t *pudp)
> +static inline void __raw_pud_clear(pud_t *pudp)
> {
> - set_pud(pudp, __pud(0));
> + __raw_set_pud(pudp, __pud(0));
> }
>
> -static inline phys_addr_t pud_page_paddr(pud_t pud)
> +static inline phys_addr_t __raw_pud_page_paddr(pud_t pud)
> {
> return __pud_to_phys(pud);
> }
>
> +#if CONFIG_PGTABLE_LEVELS > 2
> +
> +#define pmd_ERROR(pmd) __pmd_error(__FILE__, __LINE__, pmd_val(pmd))
> +
> +#define pud_none(pud) __raw_pud_none(pud)
> +#define pud_bad(pud) __raw_pud_bad(pud)
> +#define pud_present(pud) __raw_pud_present(pud)
> +
> +#define set_pud(pudp, pud) __raw_set_pud((pudp), (pud))
> +#define pud_clear(pudp) __raw_pud_clear((pudp))
> +#define pud_page_paddr(pud) __raw_pud_page_paddr((pud))
> +
> /* Find an entry in the second-level page table. */
> #define pmd_index(addr) (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
>
> @@ -528,30 +536,38 @@ static inline phys_addr_t pud_page_paddr(pud_t pud)
>
> #endif /* CONFIG_PGTABLE_LEVELS > 2 */
>
> -#if CONFIG_PGTABLE_LEVELS > 3
> +#define __raw_pgd_none(pgd) (!pgd_val(pgd))
> +#define __raw_pgd_bad(pgd) (!(pgd_val(pgd) & 2))
> +#define __raw_pgd_present(pgd) (pgd_val(pgd))
>
> -#define pud_ERROR(pud) __pud_error(__FILE__, __LINE__, pud_val(pud))
> -
> -#define pgd_none(pgd) (!pgd_val(pgd))
> -#define pgd_bad(pgd) (!(pgd_val(pgd) & 2))
> -#define pgd_present(pgd) (pgd_val(pgd))
> -
> -static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
> +static inline void __raw_set_pgd(pgd_t *pgdp, pgd_t pgd)
> {
> WRITE_ONCE(*pgdp, pgd);
> dsb(ishst);
> }
>
> -static inline void pgd_clear(pgd_t *pgdp)
> +static inline void __raw_pgd_clear(pgd_t *pgdp)
> {
> - set_pgd(pgdp, __pgd(0));
> + __raw_set_pgd(pgdp, __pgd(0));
> }
>
> -static inline phys_addr_t pgd_page_paddr(pgd_t pgd)
> +static inline phys_addr_t __raw_pgd_page_paddr(pgd_t pgd)
> {
> return __pgd_to_phys(pgd);
> }
>
> +#if CONFIG_PGTABLE_LEVELS > 3
> +
> +#define pud_ERROR(pud) __pud_error(__FILE__, __LINE__, pud_val(pud))
> +
> +#define pgd_none(pgd) __raw_pgd_none((pgd))
> +#define pgd_bad(pgd) __raw_pgd_bad((pgd))
> +#define pgd_present(pgd) __raw_pgd_present((pgd))
> +
> +#define set_pgd(pgdp, pgd) __raw_set_pgd((pgdp), (pgd))
> +#define pgd_clear(pgdp) __raw_pgd_clear((pgdp))
> +#define pgd_page_paddr(pgd) __raw_pgd_page_paddr((pgd))
> +
> /* Find an entry in the frst-level page table. */
> #define pud_index(addr) (((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
>
>
--
Julien Grall
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