diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 58faeaa7fbdc..b25d5cbe4db1 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -30,6 +30,7 @@ #include #include +#include #include #include #include @@ -62,15 +63,18 @@ pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, } EXPORT_SYMBOL(phys_mem_access_prot); -static void __init *early_alloc(unsigned long sz) +static void __init *early_pgtable_alloc(void) { phys_addr_t phys; void *ptr; - phys = memblock_alloc(sz, sz); + phys = memblock_alloc(PAGE_SIZE, PAGE_SIZE); BUG_ON(!phys); ptr = __va(phys); - memset(ptr, 0, sz); + memset(ptr, 0, PAGE_SIZE); + + /* Ensure the zeroed page is visible to the page table walker */ + dsb(ishst); return ptr; } @@ -95,12 +99,12 @@ static void split_pmd(pmd_t *pmd, pte_t *pte) static void alloc_init_pte(pmd_t *pmd, unsigned long addr, unsigned long end, unsigned long pfn, pgprot_t prot, - void *(*alloc)(unsigned long size)) + void *(*pgtable_alloc)(void)) { pte_t *pte; if (pmd_none(*pmd) || pmd_sect(*pmd)) { - pte = alloc(PTRS_PER_PTE * sizeof(pte_t)); + pte = pgtable_alloc(); if (pmd_sect(*pmd)) split_pmd(pmd, pte); __pmd_populate(pmd, __pa(pte), PMD_TYPE_TABLE); @@ -130,7 +134,7 @@ static void split_pud(pud_t *old_pud, pmd_t *pmd) static void alloc_init_pmd(struct mm_struct *mm, pud_t *pud, unsigned long addr, unsigned long end, phys_addr_t phys, pgprot_t prot, - void *(*alloc)(unsigned long size)) + void *(*pgtable_alloc)(void)) { pmd_t *pmd; unsigned long next; @@ -139,7 +143,7 @@ static void alloc_init_pmd(struct mm_struct *mm, pud_t *pud, * Check for initial section mappings in the pgd/pud and remove them. */ if (pud_none(*pud) || pud_sect(*pud)) { - pmd = alloc(PTRS_PER_PMD * sizeof(pmd_t)); + pmd = pgtable_alloc(); if (pud_sect(*pud)) { /* * need to have the 1G of mappings continue to be @@ -174,7 +178,7 @@ static void alloc_init_pmd(struct mm_struct *mm, pud_t *pud, } } else { alloc_init_pte(pmd, addr, next, __phys_to_pfn(phys), - prot, alloc); + prot, pgtable_alloc); } phys += next - addr; } while (pmd++, addr = next, addr != end); @@ -195,13 +199,13 @@ static inline bool use_1G_block(unsigned long addr, unsigned long next, static void alloc_init_pud(struct mm_struct *mm, pgd_t *pgd, unsigned long addr, unsigned long end, phys_addr_t phys, pgprot_t prot, - void *(*alloc)(unsigned long size)) + void *(*pgtable_alloc)(void)) { pud_t *pud; unsigned long next; if (pgd_none(*pgd)) { - pud = alloc(PTRS_PER_PUD * sizeof(pud_t)); + pud = pgtable_alloc(); pgd_populate(mm, pgd, pud); } BUG_ON(pgd_bad(*pgd)); @@ -234,7 +238,8 @@ static void alloc_init_pud(struct mm_struct *mm, pgd_t *pgd, } } } else { - alloc_init_pmd(mm, pud, addr, next, phys, prot, alloc); + alloc_init_pmd(mm, pud, addr, next, phys, prot, + pgtable_alloc); } phys += next - addr; } while (pud++, addr = next, addr != end); @@ -247,7 +252,7 @@ static void alloc_init_pud(struct mm_struct *mm, pgd_t *pgd, static void __create_mapping(struct mm_struct *mm, pgd_t *pgd, phys_addr_t phys, unsigned long virt, phys_addr_t size, pgprot_t prot, - void *(*alloc)(unsigned long size)) + void *(*pgtable_alloc)(void)) { unsigned long addr, length, end, next; @@ -265,18 +270,18 @@ static void __create_mapping(struct mm_struct *mm, pgd_t *pgd, end = addr + length; do { next = pgd_addr_end(addr, end); - alloc_init_pud(mm, pgd, addr, next, phys, prot, alloc); + alloc_init_pud(mm, pgd, addr, next, phys, prot, pgtable_alloc); phys += next - addr; } while (pgd++, addr = next, addr != end); } -static void *late_alloc(unsigned long size) +static void *late_pgtable_alloc(void) { - void *ptr; - - BUG_ON(size > PAGE_SIZE); - ptr = (void *)__get_free_page(PGALLOC_GFP); + void *ptr = (void *)__get_free_page(PGALLOC_GFP); BUG_ON(!ptr); + + /* Ensure the zeroed page is visible to the page table walker */ + dsb(ishst); return ptr; } @@ -289,7 +294,7 @@ static void __init create_mapping(phys_addr_t phys, unsigned long virt, return; } __create_mapping(&init_mm, pgd_offset_k(virt), phys, virt, - size, prot, early_alloc); + size, prot, early_pgtable_alloc); } void __init create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys, @@ -297,7 +302,7 @@ void __init create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys, pgprot_t prot) { __create_mapping(mm, pgd_offset(mm, virt), phys, virt, size, prot, - late_alloc); + late_pgtable_alloc); } static void create_mapping_late(phys_addr_t phys, unsigned long virt, @@ -310,7 +315,7 @@ static void create_mapping_late(phys_addr_t phys, unsigned long virt, } return __create_mapping(&init_mm, pgd_offset_k(virt), - phys, virt, size, prot, late_alloc); + phys, virt, size, prot, late_pgtable_alloc); } #ifdef CONFIG_DEBUG_RODATA @@ -460,15 +465,12 @@ void __init paging_init(void) fixup_executable(); /* allocate the zero page. */ - zero_page = early_alloc(PAGE_SIZE); + zero_page = early_pgtable_alloc(); bootmem_init(); empty_zero_page = virt_to_page(zero_page); - /* Ensure the zero page is visible to the page table walker */ - dsb(ishst); - /* * TTBR0 is only used for the identity mapping at this stage. Make it * point to zero page to avoid speculatively fetching new entries.