From: Catalin Marinas <catalin.marinas@xxxxxxx> Subject: arm64: provide pmdp_establish() helper We need an atomic way to setup pmd page table entry, avoiding races with CPU setting dirty/accessed bits. This is required to implement pmdp_invalidate() that doesn't lose these bits. Link: http://lkml.kernel.org/r/20171213105756.69879-5-kirill.shutemov@xxxxxxxxxxxxxxx Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/arm64/include/asm/pgtable.h | 7 +++++++ 1 file changed, 7 insertions(+) diff -puN arch/arm64/include/asm/pgtable.h~arm64-provide-pmdp_establish-helper arch/arm64/include/asm/pgtable.h --- a/arch/arm64/include/asm/pgtable.h~arm64-provide-pmdp_establish-helper +++ a/arch/arm64/include/asm/pgtable.h @@ -706,6 +706,13 @@ static inline void pmdp_set_wrprotect(st { ptep_set_wrprotect(mm, address, (pte_t *)pmdp); } + +#define pmdp_establish pmdp_establish +static inline pmd_t pmdp_establish(struct vm_area_struct *vma, + unsigned long address, pmd_t *pmdp, pmd_t pmd) +{ + return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd))); +} #endif extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
