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Diffstat (limited to 'arch/arm/include/asm/pgtable-3level.h')
-rw-r--r-- | arch/arm/include/asm/pgtable-3level.h | 253 |
1 files changed, 253 insertions, 0 deletions
diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h new file mode 100644 index 0000000000..71c3add641 --- /dev/null +++ b/arch/arm/include/asm/pgtable-3level.h @@ -0,0 +1,253 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * arch/arm/include/asm/pgtable-3level.h + * + * Copyright (C) 2011 ARM Ltd. + * Author: Catalin Marinas <catalin.marinas@arm.com> + */ +#ifndef _ASM_PGTABLE_3LEVEL_H +#define _ASM_PGTABLE_3LEVEL_H + +/* + * With LPAE, there are 3 levels of page tables. Each level has 512 entries of + * 8 bytes each, occupying a 4K page. The first level table covers a range of + * 512GB, each entry representing 1GB. Since we are limited to 4GB input + * address range, only 4 entries in the PGD are used. + * + * There are enough spare bits in a page table entry for the kernel specific + * state. + */ +#define PTRS_PER_PTE 512 +#define PTRS_PER_PMD 512 +#define PTRS_PER_PGD 4 + +#define PTE_HWTABLE_PTRS (0) +#define PTE_HWTABLE_OFF (0) +#define PTE_HWTABLE_SIZE (PTRS_PER_PTE * sizeof(u64)) + +#define MAX_POSSIBLE_PHYSMEM_BITS 40 + +/* + * PGDIR_SHIFT determines the size a top-level page table entry can map. + */ +#define PGDIR_SHIFT 30 + +/* + * PMD_SHIFT determines the size a middle-level page table entry can map. + */ +#define PMD_SHIFT 21 + +#define PMD_SIZE (1UL << PMD_SHIFT) +#define PMD_MASK (~((1 << PMD_SHIFT) - 1)) +#define PGDIR_SIZE (1UL << PGDIR_SHIFT) +#define PGDIR_MASK (~((1 << PGDIR_SHIFT) - 1)) + +/* + * section address mask and size definitions. + */ +#define SECTION_SHIFT 21 +#define SECTION_SIZE (1UL << SECTION_SHIFT) +#define SECTION_MASK (~((1 << SECTION_SHIFT) - 1)) + +#define USER_PTRS_PER_PGD (PAGE_OFFSET / PGDIR_SIZE) + +/* + * Hugetlb definitions. + */ +#define HPAGE_SHIFT PMD_SHIFT +#define HPAGE_SIZE (_AC(1, UL) << HPAGE_SHIFT) +#define HPAGE_MASK (~(HPAGE_SIZE - 1)) +#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT) + +/* + * "Linux" PTE definitions for LPAE. + * + * These bits overlap with the hardware bits but the naming is preserved for + * consistency with the classic page table format. + */ +#define L_PTE_VALID (_AT(pteval_t, 1) << 0) /* Valid */ +#define L_PTE_PRESENT (_AT(pteval_t, 3) << 0) /* Present */ +#define L_PTE_USER (_AT(pteval_t, 1) << 6) /* AP[1] */ +#define L_PTE_SHARED (_AT(pteval_t, 3) << 8) /* SH[1:0], inner shareable */ +#define L_PTE_YOUNG (_AT(pteval_t, 1) << 10) /* AF */ +#define L_PTE_XN (_AT(pteval_t, 1) << 54) /* XN */ +#define L_PTE_DIRTY (_AT(pteval_t, 1) << 55) +#define L_PTE_SPECIAL (_AT(pteval_t, 1) << 56) +#define L_PTE_NONE (_AT(pteval_t, 1) << 57) /* PROT_NONE */ +#define L_PTE_RDONLY (_AT(pteval_t, 1) << 58) /* READ ONLY */ + +/* We borrow bit 7 to store the exclusive marker in swap PTEs. */ +#define L_PTE_SWP_EXCLUSIVE (_AT(pteval_t, 1) << 7) + +#define L_PMD_SECT_VALID (_AT(pmdval_t, 1) << 0) +#define L_PMD_SECT_DIRTY (_AT(pmdval_t, 1) << 55) +#define L_PMD_SECT_NONE (_AT(pmdval_t, 1) << 57) +#define L_PMD_SECT_RDONLY (_AT(pteval_t, 1) << 58) + +/* + * To be used in assembly code with the upper page attributes. + */ +#define L_PTE_XN_HIGH (1 << (54 - 32)) +#define L_PTE_DIRTY_HIGH (1 << (55 - 32)) + +/* + * AttrIndx[2:0] encoding (mapping attributes defined in the MAIR* registers). + */ +#define L_PTE_MT_UNCACHED (_AT(pteval_t, 0) << 2) /* strongly ordered */ +#define L_PTE_MT_BUFFERABLE (_AT(pteval_t, 1) << 2) /* normal non-cacheable */ +#define L_PTE_MT_WRITETHROUGH (_AT(pteval_t, 2) << 2) /* normal inner write-through */ +#define L_PTE_MT_WRITEBACK (_AT(pteval_t, 3) << 2) /* normal inner write-back */ +#define L_PTE_MT_WRITEALLOC (_AT(pteval_t, 7) << 2) /* normal inner write-alloc */ +#define L_PTE_MT_DEV_SHARED (_AT(pteval_t, 4) << 2) /* device */ +#define L_PTE_MT_DEV_NONSHARED (_AT(pteval_t, 4) << 2) /* device */ +#define L_PTE_MT_DEV_WC (_AT(pteval_t, 1) << 2) /* normal non-cacheable */ +#define L_PTE_MT_DEV_CACHED (_AT(pteval_t, 3) << 2) /* normal inner write-back */ +#define L_PTE_MT_MASK (_AT(pteval_t, 7) << 2) + +/* + * Software PGD flags. + */ +#define L_PGD_SWAPPER (_AT(pgdval_t, 1) << 55) /* swapper_pg_dir entry */ + +#ifndef __ASSEMBLY__ + +#define pud_none(pud) (!pud_val(pud)) +#define pud_bad(pud) (!(pud_val(pud) & 2)) +#define pud_present(pud) (pud_val(pud)) +#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \ + PMD_TYPE_TABLE) +#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \ + PMD_TYPE_SECT) +#define pmd_large(pmd) pmd_sect(pmd) +#define pmd_leaf(pmd) pmd_sect(pmd) + +#define pud_clear(pudp) \ + do { \ + *pudp = __pud(0); \ + clean_pmd_entry(pudp); \ + } while (0) + +#define set_pud(pudp, pud) \ + do { \ + *pudp = pud; \ + flush_pmd_entry(pudp); \ + } while (0) + +static inline pmd_t *pud_pgtable(pud_t pud) +{ + return __va(pud_val(pud) & PHYS_MASK & (s32)PAGE_MASK); +} + +#define pmd_bad(pmd) (!(pmd_val(pmd) & 2)) + +#define copy_pmd(pmdpd,pmdps) \ + do { \ + *pmdpd = *pmdps; \ + flush_pmd_entry(pmdpd); \ + } while (0) + +#define pmd_clear(pmdp) \ + do { \ + *pmdp = __pmd(0); \ + clean_pmd_entry(pmdp); \ + } while (0) + +/* + * For 3 levels of paging the PTE_EXT_NG bit will be set for user address ptes + * that are written to a page table but not for ptes created with mk_pte. + * + * In hugetlb_no_page, a new huge pte (new_pte) is generated and passed to + * hugetlb_cow, where it is compared with an entry in a page table. + * This comparison test fails erroneously leading ultimately to a memory leak. + * + * To correct this behaviour, we mask off PTE_EXT_NG for any pte that is + * present before running the comparison. + */ +#define __HAVE_ARCH_PTE_SAME +#define pte_same(pte_a,pte_b) ((pte_present(pte_a) ? pte_val(pte_a) & ~PTE_EXT_NG \ + : pte_val(pte_a)) \ + == (pte_present(pte_b) ? pte_val(pte_b) & ~PTE_EXT_NG \ + : pte_val(pte_b))) + +#define set_pte_ext(ptep,pte,ext) cpu_set_pte_ext(ptep,__pte(pte_val(pte)|(ext))) + +#define pte_huge(pte) (pte_val(pte) && !(pte_val(pte) & PTE_TABLE_BIT)) +#define pte_mkhuge(pte) (__pte(pte_val(pte) & ~PTE_TABLE_BIT)) + +#define pmd_isset(pmd, val) ((u32)(val) == (val) ? pmd_val(pmd) & (val) \ + : !!(pmd_val(pmd) & (val))) +#define pmd_isclear(pmd, val) (!(pmd_val(pmd) & (val))) + +#define pmd_present(pmd) (pmd_isset((pmd), L_PMD_SECT_VALID)) +#define pmd_young(pmd) (pmd_isset((pmd), PMD_SECT_AF)) +#define pte_special(pte) (pte_isset((pte), L_PTE_SPECIAL)) +static inline pte_t pte_mkspecial(pte_t pte) +{ + pte_val(pte) |= L_PTE_SPECIAL; + return pte; +} + +#define pmd_write(pmd) (pmd_isclear((pmd), L_PMD_SECT_RDONLY)) +#define pmd_dirty(pmd) (pmd_isset((pmd), L_PMD_SECT_DIRTY)) + +#define pmd_hugewillfault(pmd) (!pmd_young(pmd) || !pmd_write(pmd)) +#define pmd_thp_or_huge(pmd) (pmd_huge(pmd) || pmd_trans_huge(pmd)) + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +#define pmd_trans_huge(pmd) (pmd_val(pmd) && !pmd_table(pmd)) +#endif + +#define PMD_BIT_FUNC(fn,op) \ +static inline pmd_t pmd_##fn(pmd_t pmd) { pmd_val(pmd) op; return pmd; } + +PMD_BIT_FUNC(wrprotect, |= L_PMD_SECT_RDONLY); +PMD_BIT_FUNC(mkold, &= ~PMD_SECT_AF); +PMD_BIT_FUNC(mkwrite_novma, &= ~L_PMD_SECT_RDONLY); +PMD_BIT_FUNC(mkdirty, |= L_PMD_SECT_DIRTY); +PMD_BIT_FUNC(mkclean, &= ~L_PMD_SECT_DIRTY); +PMD_BIT_FUNC(mkyoung, |= PMD_SECT_AF); + +#define pmd_mkhuge(pmd) (__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT)) + +#define pmd_pfn(pmd) (((pmd_val(pmd) & PMD_MASK) & PHYS_MASK) >> PAGE_SHIFT) +#define pfn_pmd(pfn,prot) (__pmd(((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))) +#define mk_pmd(page,prot) pfn_pmd(page_to_pfn(page),prot) + +/* No hardware dirty/accessed bits -- generic_pmdp_establish() fits */ +#define pmdp_establish generic_pmdp_establish + +/* represent a notpresent pmd by faulting entry, this is used by pmdp_invalidate */ +static inline pmd_t pmd_mkinvalid(pmd_t pmd) +{ + return __pmd(pmd_val(pmd) & ~L_PMD_SECT_VALID); +} + +static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) +{ + const pmdval_t mask = PMD_SECT_USER | PMD_SECT_XN | L_PMD_SECT_RDONLY | + L_PMD_SECT_VALID | L_PMD_SECT_NONE; + pmd_val(pmd) = (pmd_val(pmd) & ~mask) | (pgprot_val(newprot) & mask); + return pmd; +} + +static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr, + pmd_t *pmdp, pmd_t pmd) +{ + BUG_ON(addr >= TASK_SIZE); + + /* create a faulting entry if PROT_NONE protected */ + if (pmd_val(pmd) & L_PMD_SECT_NONE) + pmd_val(pmd) &= ~L_PMD_SECT_VALID; + + if (pmd_write(pmd) && pmd_dirty(pmd)) + pmd_val(pmd) &= ~PMD_SECT_AP2; + else + pmd_val(pmd) |= PMD_SECT_AP2; + + *pmdp = __pmd(pmd_val(pmd) | PMD_SECT_nG); + flush_pmd_entry(pmdp); +} + +#endif /* __ASSEMBLY__ */ + +#endif /* _ASM_PGTABLE_3LEVEL_H */ |