Le 30/11/2023 à 03:53, Rohan McLure a écrit :
> The check that a higher-level entry in multi-level pages contains a page
> translation entry (pte) is performed by p{m,u,4}d_leaf stubs, which may
> be specialised for each choice of mmu. In a prior commit, we replace
> uses to the catch-all stubs, p{m,u,4}d_is_leaf with p{m,u,4}d_leaf.
>
> Replace the catch-all stub definitions for p{m,u,4}d_is_leaf with
> definitions for p{m,u,4}d_leaf. A future patch will assume that
> p{m,u,4}d_leaf is defined on all platforms.
>
> In particular, implement pud_leaf for Book3E-64, pmd_leaf for all Book3E
> and Book3S-64 platforms, with a catch-all definition for p4d_leaf.
Is that needed ? There are fallback definitions of all pXd_leaf() in
include/linux/pgtable.h
>
> Reviewed-by: Christophe Leroy <christophe.le...@csgroup.eu>
> Signed-off-by: Rohan McLure <rmcl...@linux.ibm.com>
> ---
> v9: No longer required in order implement page table check, just
> refactoring.
> ---
> arch/powerpc/include/asm/book3s/32/pgtable.h | 5 +++++
> arch/powerpc/include/asm/book3s/64/pgtable.h | 10 ++++-----
> arch/powerpc/include/asm/nohash/64/pgtable.h | 6 ++++++
> arch/powerpc/include/asm/pgtable.h | 22 ++------------------
> 4 files changed, 17 insertions(+), 26 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h
> b/arch/powerpc/include/asm/book3s/32/pgtable.h
> index 52971ee30717..9cc95a61d2a6 100644
> --- a/arch/powerpc/include/asm/book3s/32/pgtable.h
> +++ b/arch/powerpc/include/asm/book3s/32/pgtable.h
> @@ -223,6 +223,11 @@ static inline void pmd_clear(pmd_t *pmdp)
> *pmdp = __pmd(0);
> }
>
> +#define pmd_leaf pmd_leaf
> +static inline bool pmd_leaf(pmd_t pmd)
> +{
> + return false;
> +}
Is that needed ? There is a fallback definition of pmd_leaf() in
include/linux/pgtable.h
>
> /*
> * When flushing the tlb entry for a page, we also need to flush the hash
> diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h
> b/arch/powerpc/include/asm/book3s/64/pgtable.h
> index cb77eddca54b..8fdb7667c509 100644
> --- a/arch/powerpc/include/asm/book3s/64/pgtable.h
> +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
> @@ -1459,16 +1459,14 @@ static inline bool is_pte_rw_upgrade(unsigned long
> old_val, unsigned long new_va
> /*
> * Like pmd_huge() and pmd_large(), but works regardless of config options
> */
> -#define pmd_is_leaf pmd_is_leaf
> -#define pmd_leaf pmd_is_leaf
> -static inline bool pmd_is_leaf(pmd_t pmd)
> +#define pmd_leaf pmd_leaf
> +static inline bool pmd_leaf(pmd_t pmd)
> {
> return !!(pmd_raw(pmd) & cpu_to_be64(_PAGE_PTE));
> }
>
> -#define pud_is_leaf pud_is_leaf
> -#define pud_leaf pud_is_leaf
> -static inline bool pud_is_leaf(pud_t pud)
> +#define pud_leaf pud_leaf
> +static inline bool pud_leaf(pud_t pud)
> {
> return !!(pud_raw(pud) & cpu_to_be64(_PAGE_PTE));
> }
> diff --git a/arch/powerpc/include/asm/nohash/64/pgtable.h
> b/arch/powerpc/include/asm/nohash/64/pgtable.h
> index 2202c78730e8..f58cbebde26e 100644
> --- a/arch/powerpc/include/asm/nohash/64/pgtable.h
> +++ b/arch/powerpc/include/asm/nohash/64/pgtable.h
> @@ -116,6 +116,12 @@ static inline void pud_clear(pud_t *pudp)
> *pudp = __pud(0);
> }
>
> +#define pud_leaf pud_leaf
> +static inline bool pud_leaf(pud_t pud)
> +{
> + return false;
> +}
> +
Is that needed ? There is a fallback definition of pud_leaf() in
include/linux/pgtable.h
> #define pud_none(pud) (!pud_val(pud))
> #define pud_bad(pud) (!is_kernel_addr(pud_val(pud)) \
> || (pud_val(pud) & PUD_BAD_BITS))
> diff --git a/arch/powerpc/include/asm/pgtable.h
> b/arch/powerpc/include/asm/pgtable.h
> index 9224f23065ff..db0231afca9d 100644
> --- a/arch/powerpc/include/asm/pgtable.h
> +++ b/arch/powerpc/include/asm/pgtable.h
> @@ -180,29 +180,11 @@ static inline void pte_frag_set(mm_context_t *ctx, void
> *p)
> }
> #endif
>
> -#ifndef pmd_is_leaf
> -#define pmd_is_leaf pmd_is_leaf
> -static inline bool pmd_is_leaf(pmd_t pmd)
> +#define p4d_leaf p4d_leaf
> +static inline bool p4d_leaf(p4d_t p4d)
> {
> return false;
> }
Is that needed ? There is a fallback definition of p4d_leaf() in
include/linux/pgtable.h
> -#endif
> -
> -#ifndef pud_is_leaf
> -#define pud_is_leaf pud_is_leaf
> -static inline bool pud_is_leaf(pud_t pud)
> -{
> - return false;
> -}
> -#endif
> -
> -#ifndef p4d_is_leaf
> -#define p4d_is_leaf p4d_is_leaf
> -static inline bool p4d_is_leaf(p4d_t p4d)
> -{
> - return false;
> -}
> -#endif
>
> #define pmd_pgtable pmd_pgtable
> static inline pgtable_t pmd_pgtable(pmd_t pmd)
