diff options
| -rw-r--r-- | arch/arm64/include/asm/pgtable.h | 4 | ||||
| -rw-r--r-- | arch/arm64/mm/mmu.c | 22 |
2 files changed, 24 insertions, 2 deletions
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index c9e4e00a9af2..491ba0a6492d 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -182,6 +182,10 @@ static inline pteval_t __phys_to_pte_val(phys_addr_t phys) */ #define pte_valid_cont(pte) (pte_valid(pte) && pte_cont(pte)) /* + * Returns true if the pte is valid and has the contiguous bit cleared. + */ +#define pte_valid_noncont(pte) (pte_valid(pte) && !pte_cont(pte)) +/* * Could the pte be present in the TLB? We must check mm_tlb_flush_pending * so that we don't erroneously return false for pages that have been * remapped as PROT_NONE but are yet to be flushed from the TLB. diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 1db44adc8717..1f2ec06a8736 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -187,6 +187,14 @@ static void init_pte(pte_t *ptep, unsigned long addr, unsigned long end, } while (ptep++, addr += PAGE_SIZE, addr != end); } +static bool pte_range_has_valid_noncont(pte_t *ptep) +{ + for (int i = 0; i < CONT_PTES; i++) + if (pte_valid_noncont(__ptep_get(&ptep[i]))) + return true; + return false; +} + static int alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr, unsigned long end, phys_addr_t phys, pgprot_t prot, @@ -224,7 +232,8 @@ static int alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr, /* use a contiguous mapping if the range is suitably aligned */ if ((((addr | next | phys) & ~CONT_PTE_MASK) == 0) && - (flags & NO_CONT_MAPPINGS) == 0) + (flags & NO_CONT_MAPPINGS) == 0 && + !pte_range_has_valid_noncont(ptep)) __prot = __pgprot(pgprot_val(prot) | PTE_CONT); init_pte(ptep, addr, next, phys, __prot); @@ -283,6 +292,14 @@ static int init_pmd(pmd_t *pmdp, unsigned long addr, unsigned long end, return 0; } +static bool pmd_range_has_valid_noncont(pmd_t *pmdp) +{ + for (int i = 0; i < CONT_PMDS; i++) + if (pte_valid_noncont(pmd_pte(READ_ONCE(pmdp[i])))) + return true; + return false; +} + static int alloc_init_cont_pmd(pud_t *pudp, unsigned long addr, unsigned long end, phys_addr_t phys, pgprot_t prot, @@ -324,7 +341,8 @@ static int alloc_init_cont_pmd(pud_t *pudp, unsigned long addr, /* use a contiguous mapping if the range is suitably aligned */ if ((((addr | next | phys) & ~CONT_PMD_MASK) == 0) && - (flags & NO_CONT_MAPPINGS) == 0) + (flags & NO_CONT_MAPPINGS) == 0 && + !pmd_range_has_valid_noncont(pmdp)) __prot = __pgprot(pgprot_val(prot) | PTE_CONT); ret = init_pmd(pmdp, addr, next, phys, __prot, pgtable_alloc, flags); |