walk_page_range() is going to be allowed to walk page tables other than those of user space. For this it needs to know when it has reached a 'leaf' entry in the page tables. This information will be provided by the p?d_large() functions/macros. For arm64, we already have p?d_sect() macros which we can reuse for p?d_large(). pud_sect() is defined as a dummy function when CONFIG_PGTABLE_LEVELS < 3 or CONFIG_ARM64_64K_PAGES is defined. However when the kernel is configured this way then architecturally it isn't allowed to have a large page that this level, and any code using these page walking macros is implicitly relying on the page size/number of levels being the same as the kernel. So it is safe to reuse this for p?d_large() as it is an architectural restriction. CC: Catalin Marinas <catalin.marinas@xxxxxxx> CC: Will Deacon <will.deacon@xxxxxxx> Signed-off-by: Steven Price <steven.price@xxxxxxx> --- arch/arm64/include/asm/pgtable.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index de70c1eabf33..6eef345dbaf4 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -428,6 +428,7 @@ extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, PMD_TYPE_TABLE) #define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \ PMD_TYPE_SECT) +#define pmd_large(pmd) pmd_sect(pmd) #if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3 #define pud_sect(pud) (0) @@ -511,6 +512,7 @@ static inline phys_addr_t pmd_page_paddr(pmd_t 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)) +#define pud_large(pud) pud_sect(pud) #define pud_valid(pud) pte_valid(pud_pte(pud)) static inline void set_pud(pud_t *pudp, pud_t pud) -- 2.20.1
