Prepare some basic functions used by following patches to support hardware DBM. Signed-off-by: Keqian Zhu <zhukeqian1@xxxxxxxxxx> Signed-off-by: Peng Liang <liangpeng10@xxxxxxxxxx> --- arch/arm64/include/asm/kvm_mmu.h | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index 30b0e8d6b895..8df078f0ee67 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -285,6 +285,30 @@ static inline bool kvm_s2pud_young(pud_t pud) return pud_young(pud); } +#ifdef CONFIG_ARM64_HW_AFDBM +static inline bool kvm_hw_dbm_enabled(void) +{ + return !!(read_sysreg(vtcr_el2) & VTCR_EL2_HD); +} + +static inline void kvm_set_s2pte_dbm(pte_t *ptep) +{ + pteval_t old_pteval, pteval; + + pteval = READ_ONCE(pte_val(*ptep)); + do { + old_pteval = pteval; + pteval |= PTE_DBM; + pteval = cmpxchg_relaxed(&pte_val(*ptep), old_pteval, pteval); + } while (pteval != old_pteval); +} + +static inline bool kvm_s2pte_dbm(pte_t *ptep) +{ + return !!(READ_ONCE(pte_val(*ptep)) & PTE_DBM); +} +#endif /* CONFIG_ARM64_HW_AFDBM */ + #define hyp_pte_table_empty(ptep) kvm_page_empty(ptep) #ifdef __PAGETABLE_PMD_FOLDED -- 2.19.1 _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm