diff options
| -rw-r--r-- | arch/x86/kvm/mmu/spte.c | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/arch/x86/kvm/mmu/spte.c b/arch/x86/kvm/mmu/spte.c index f262c380f40e..3f16c91aa042 100644 --- a/arch/x86/kvm/mmu/spte.c +++ b/arch/x86/kvm/mmu/spte.c @@ -104,7 +104,7 @@ u64 make_mmio_spte(struct kvm_vcpu *vcpu, u64 gfn, unsigned int access) return spte; } -static bool kvm_is_mmio_pfn(kvm_pfn_t pfn) +static bool __kvm_is_mmio_pfn(kvm_pfn_t pfn) { if (pfn_valid(pfn)) return !is_zero_pfn(pfn) && PageReserved(pfn_to_page(pfn)) && @@ -125,6 +125,19 @@ static bool kvm_is_mmio_pfn(kvm_pfn_t pfn) E820_TYPE_RAM); } +static bool kvm_is_mmio_pfn(kvm_pfn_t pfn, int *is_host_mmio) +{ + /* + * Determining if a PFN is host MMIO is relative expensive. Cache the + * result locally (in the sole caller) to avoid doing the full query + * multiple times when creating a single SPTE. + */ + if (*is_host_mmio < 0) + *is_host_mmio = __kvm_is_mmio_pfn(pfn); + + return *is_host_mmio; +} + /* * Returns true if the SPTE needs to be updated atomically due to having bits * that may be changed without holding mmu_lock, and for which KVM must not @@ -162,6 +175,7 @@ bool make_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, { int level = sp->role.level; u64 spte = SPTE_MMU_PRESENT_MASK; + int is_host_mmio = -1; bool wrprot = false; /* @@ -210,14 +224,14 @@ bool make_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, spte |= PT_PAGE_SIZE_MASK; if (kvm_x86_ops.get_mt_mask) - spte |= kvm_x86_call(get_mt_mask)(vcpu, gfn, kvm_is_mmio_pfn(pfn)); - + spte |= kvm_x86_call(get_mt_mask)(vcpu, gfn, + kvm_is_mmio_pfn(pfn, &is_host_mmio)); if (host_writable) spte |= shadow_host_writable_mask; else pte_access &= ~ACC_WRITE_MASK; - if (shadow_me_value && !kvm_is_mmio_pfn(pfn)) + if (shadow_me_value && !kvm_is_mmio_pfn(pfn, &is_host_mmio)) spte |= shadow_me_value; spte |= (u64)pfn << PAGE_SHIFT; |