From: Peter Xu <peterx@xxxxxxxxxx> PowerPC book3s 4K mostly has the same definition on both, except pXd_huge() constantly returns 0 for hash MMUs. As Michael Ellerman pointed out [1], it is safe to check _PAGE_PTE on hash MMUs, as the bit will never be set so it will keep returning false. As a reference, __p[mu]d_mkhuge() will trigger a BUG_ON trying to create such huge mappings for 4K hash MMUs. Meanwhile, the major powerpc hugetlb pgtable walker __find_linux_pte() already used pXd_leaf() to check leaf hugetlb mappings. The goal should be that we will have one API pXd_leaf() to detect all kinds of huge mappings (hugepd is still special in this case, though). AFAICT we need to use the pXd_leaf() impl (rather than pXd_huge()'s) to make sure ie. THPs on hash MMU will also return true. This helps to simplify a follow up patch to drop pXd_huge() treewide. NOTE: *_leaf() definition need to be moved before the inclusion of asm/book3s/64/pgtable-4k.h, which defines pXd_huge() with it. [1] https://lore.kernel.org/r/87v85zo6w7.fsf@mail.lhotse Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Nicholas Piggin <npiggin@xxxxxxxxx> Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx> Cc: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxx> Cc: "Naveen N. Rao" <naveen.n.rao@xxxxxxxxxxxxx> Cc: linuxppc-dev@xxxxxxxxxxxxxxxx Signed-off-by: Peter Xu <peterx@xxxxxxxxxx> --- .../include/asm/book3s/64/pgtable-4k.h | 14 ++-------- arch/powerpc/include/asm/book3s/64/pgtable.h | 27 +++++++++---------- 2 files changed, 14 insertions(+), 27 deletions(-) diff --git a/arch/powerpc/include/asm/book3s/64/pgtable-4k.h b/arch/powerpc/include/asm/book3s/64/pgtable-4k.h index 48f21820afe2..92545981bb49 100644 --- a/arch/powerpc/include/asm/book3s/64/pgtable-4k.h +++ b/arch/powerpc/include/asm/book3s/64/pgtable-4k.h @@ -8,22 +8,12 @@ #ifdef CONFIG_HUGETLB_PAGE static inline int pmd_huge(pmd_t pmd) { - /* - * leaf pte for huge page - */ - if (radix_enabled()) - return !!(pmd_raw(pmd) & cpu_to_be64(_PAGE_PTE)); - return 0; + return pmd_leaf(pmd); } static inline int pud_huge(pud_t pud) { - /* - * leaf pte for huge page - */ - if (radix_enabled()) - return !!(pud_raw(pud) & cpu_to_be64(_PAGE_PTE)); - return 0; + return pud_leaf(pud); } /* diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h index df66dce8306f..fd7180fded75 100644 --- a/arch/powerpc/include/asm/book3s/64/pgtable.h +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h @@ -262,6 +262,18 @@ extern unsigned long __kernel_io_end; extern struct page *vmemmap; extern unsigned long pci_io_base; + +#define pmd_leaf pmd_leaf +static inline bool pmd_leaf(pmd_t pmd) +{ + return !!(pmd_raw(pmd) & cpu_to_be64(_PAGE_PTE)); +} + +#define pud_leaf pud_leaf +static inline bool pud_leaf(pud_t pud) +{ + return !!(pud_raw(pud) & cpu_to_be64(_PAGE_PTE)); +} #endif /* __ASSEMBLY__ */ #include <asm/book3s/64/hash.h> @@ -1436,20 +1448,5 @@ static inline bool is_pte_rw_upgrade(unsigned long old_val, unsigned long new_va return false; } -/* - * Like pmd_huge(), but works regardless of config options - */ -#define pmd_leaf pmd_leaf -static inline bool pmd_leaf(pmd_t pmd) -{ - return !!(pmd_raw(pmd) & cpu_to_be64(_PAGE_PTE)); -} - -#define pud_leaf pud_leaf -static inline bool pud_leaf(pud_t pud) -{ - return !!(pud_raw(pud) & cpu_to_be64(_PAGE_PTE)); -} - #endif /* __ASSEMBLY__ */ #endif /* _ASM_POWERPC_BOOK3S_64_PGTABLE_H_ */ -- 2.44.0
