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Diffstat (limited to 'arch/arm64/include/asm/stage2_pgtable.h')
| -rw-r--r-- | arch/arm64/include/asm/stage2_pgtable.h | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/stage2_pgtable.h b/arch/arm64/include/asm/stage2_pgtable.h new file mode 100644 index 000000000000..8b68099348e5 --- /dev/null +++ b/arch/arm64/include/asm/stage2_pgtable.h @@ -0,0 +1,142 @@ +/* + * Copyright (C) 2016 - ARM Ltd + * + * stage2 page table helpers + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#ifndef __ARM64_S2_PGTABLE_H_ +#define __ARM64_S2_PGTABLE_H_ + +#include <asm/pgtable.h> + +/* + * The hardware supports concatenation of up to 16 tables at stage2 entry level + * and we use the feature whenever possible. + * + * Now, the minimum number of bits resolved at any level is (PAGE_SHIFT - 3). + * On arm64, the smallest PAGE_SIZE supported is 4k, which means + * (PAGE_SHIFT - 3) > 4 holds for all page sizes. + * This implies, the total number of page table levels at stage2 expected + * by the hardware is actually the number of levels required for (KVM_PHYS_SHIFT - 4) + * in normal translations(e.g, stage1), since we cannot have another level in + * the range (KVM_PHYS_SHIFT, KVM_PHYS_SHIFT - 4). + */ +#define STAGE2_PGTABLE_LEVELS ARM64_HW_PGTABLE_LEVELS(KVM_PHYS_SHIFT - 4) + +/* + * With all the supported VA_BITs and 40bit guest IPA, the following condition + * is always true: + * + * STAGE2_PGTABLE_LEVELS <= CONFIG_PGTABLE_LEVELS + * + * We base our stage-2 page table walker helpers on this assumption and + * fall back to using the host version of the helper wherever possible. + * i.e, if a particular level is not folded (e.g, PUD) at stage2, we fall back + * to using the host version, since it is guaranteed it is not folded at host. + * + * If the condition breaks in the future, we can rearrange the host level + * definitions and reuse them for stage2. Till then... + */ +#if STAGE2_PGTABLE_LEVELS > CONFIG_PGTABLE_LEVELS +#error "Unsupported combination of guest IPA and host VA_BITS." +#endif + +/* S2_PGDIR_SHIFT is the size mapped by top-level stage2 entry */ +#define S2_PGDIR_SHIFT ARM64_HW_PGTABLE_LEVEL_SHIFT(4 - STAGE2_PGTABLE_LEVELS) +#define S2_PGDIR_SIZE (_AC(1, UL) << S2_PGDIR_SHIFT) +#define S2_PGDIR_MASK (~(S2_PGDIR_SIZE - 1)) + +/* + * The number of PTRS across all concatenated stage2 tables given by the + * number of bits resolved at the initial level. + */ +#define PTRS_PER_S2_PGD (1 << (KVM_PHYS_SHIFT - S2_PGDIR_SHIFT)) + +/* + * KVM_MMU_CACHE_MIN_PAGES is the number of stage2 page table translation + * levels in addition to the PGD. + */ +#define KVM_MMU_CACHE_MIN_PAGES (STAGE2_PGTABLE_LEVELS - 1) + + +#if STAGE2_PGTABLE_LEVELS > 3 + +#define S2_PUD_SHIFT ARM64_HW_PGTABLE_LEVEL_SHIFT(1) +#define S2_PUD_SIZE (_AC(1, UL) << S2_PUD_SHIFT) +#define S2_PUD_MASK (~(S2_PUD_SIZE - 1)) + +#define stage2_pgd_none(pgd) pgd_none(pgd) +#define stage2_pgd_clear(pgd) pgd_clear(pgd) +#define stage2_pgd_present(pgd) pgd_present(pgd) +#define stage2_pgd_populate(pgd, pud) pgd_populate(NULL, pgd, pud) +#define stage2_pud_offset(pgd, address) pud_offset(pgd, address) +#define stage2_pud_free(pud) pud_free(NULL, pud) + +#define stage2_pud_table_empty(pudp) kvm_page_empty(pudp) + +static inline phys_addr_t stage2_pud_addr_end(phys_addr_t addr, phys_addr_t end) +{ + phys_addr_t boundary = (addr + S2_PUD_SIZE) & S2_PUD_MASK; + + return (boundary - 1 < end - 1) ? boundary : end; +} + +#endif /* STAGE2_PGTABLE_LEVELS > 3 */ + + +#if STAGE2_PGTABLE_LEVELS > 2 + +#define S2_PMD_SHIFT ARM64_HW_PGTABLE_LEVEL_SHIFT(2) +#define S2_PMD_SIZE (_AC(1, UL) << S2_PMD_SHIFT) +#define S2_PMD_MASK (~(S2_PMD_SIZE - 1)) + +#define stage2_pud_none(pud) pud_none(pud) +#define stage2_pud_clear(pud) pud_clear(pud) +#define stage2_pud_present(pud) pud_present(pud) +#define stage2_pud_populate(pud, pmd) pud_populate(NULL, pud, pmd) +#define stage2_pmd_offset(pud, address) pmd_offset(pud, address) +#define stage2_pmd_free(pmd) pmd_free(NULL, pmd) + +#define stage2_pud_huge(pud) pud_huge(pud) +#define stage2_pmd_table_empty(pmdp) kvm_page_empty(pmdp) + +static inline phys_addr_t stage2_pmd_addr_end(phys_addr_t addr, phys_addr_t end) +{ + phys_addr_t boundary = (addr + S2_PMD_SIZE) & S2_PMD_MASK; + + return (boundary - 1 < end - 1) ? boundary : end; +} + +#endif /* STAGE2_PGTABLE_LEVELS > 2 */ + +#define stage2_pte_table_empty(ptep) kvm_page_empty(ptep) + +#if STAGE2_PGTABLE_LEVELS == 2 +#include <asm/stage2_pgtable-nopmd.h> +#elif STAGE2_PGTABLE_LEVELS == 3 +#include <asm/stage2_pgtable-nopud.h> +#endif + + +#define stage2_pgd_index(addr) (((addr) >> S2_PGDIR_SHIFT) & (PTRS_PER_S2_PGD - 1)) + +static inline phys_addr_t stage2_pgd_addr_end(phys_addr_t addr, phys_addr_t end) +{ + phys_addr_t boundary = (addr + S2_PGDIR_SIZE) & S2_PGDIR_MASK; + + return (boundary - 1 < end - 1) ? boundary : end; +} + +#endif /* __ARM64_S2_PGTABLE_H_ */ |