diff options
| -rw-r--r-- | arch/x86/kvm/mmu.c | 82 |
1 files changed, 60 insertions, 22 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index a25173a0d8b9..9cd5a717ede5 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -2357,42 +2357,77 @@ static int mmu_check_root(struct kvm_vcpu *vcpu, gfn_t root_gfn) return ret; } -static int mmu_alloc_roots(struct kvm_vcpu *vcpu) +static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu) +{ + struct kvm_mmu_page *sp; + int i; + + if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) { + spin_lock(&vcpu->kvm->mmu_lock); + kvm_mmu_free_some_pages(vcpu); + sp = kvm_mmu_get_page(vcpu, 0, 0, PT64_ROOT_LEVEL, + 1, ACC_ALL, NULL); + ++sp->root_count; + spin_unlock(&vcpu->kvm->mmu_lock); + vcpu->arch.mmu.root_hpa = __pa(sp->spt); + } else if (vcpu->arch.mmu.shadow_root_level == PT32E_ROOT_LEVEL) { + for (i = 0; i < 4; ++i) { + hpa_t root = vcpu->arch.mmu.pae_root[i]; + + ASSERT(!VALID_PAGE(root)); + spin_lock(&vcpu->kvm->mmu_lock); + kvm_mmu_free_some_pages(vcpu); + sp = kvm_mmu_get_page(vcpu, i << 30, i << 30, + PT32_ROOT_LEVEL, 1, ACC_ALL, + NULL); + root = __pa(sp->spt); + ++sp->root_count; + spin_unlock(&vcpu->kvm->mmu_lock); + vcpu->arch.mmu.pae_root[i] = root | PT_PRESENT_MASK; + vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.pae_root); + } + } else + BUG(); + + return 0; +} + +static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu) { int i; gfn_t root_gfn; struct kvm_mmu_page *sp; - int direct = 0; u64 pdptr; root_gfn = vcpu->arch.mmu.get_cr3(vcpu) >> PAGE_SHIFT; - if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) { + if (mmu_check_root(vcpu, root_gfn)) + return 1; + + /* + * Do we shadow a long mode page table? If so we need to + * write-protect the guests page table root. + */ + if (vcpu->arch.mmu.root_level == PT64_ROOT_LEVEL) { hpa_t root = vcpu->arch.mmu.root_hpa; ASSERT(!VALID_PAGE(root)); - if (mmu_check_root(vcpu, root_gfn)) - return 1; - if (vcpu->arch.mmu.direct_map) { - direct = 1; - root_gfn = 0; - } + spin_lock(&vcpu->kvm->mmu_lock); kvm_mmu_free_some_pages(vcpu); - sp = kvm_mmu_get_page(vcpu, root_gfn, 0, - PT64_ROOT_LEVEL, direct, - ACC_ALL, NULL); + sp = kvm_mmu_get_page(vcpu, root_gfn, 0, PT64_ROOT_LEVEL, + 0, ACC_ALL, NULL); root = __pa(sp->spt); ++sp->root_count; spin_unlock(&vcpu->kvm->mmu_lock); vcpu->arch.mmu.root_hpa = root; return 0; } - direct = !is_paging(vcpu); - - if (mmu_check_root(vcpu, root_gfn)) - return 1; + /* + * We shadow a 32 bit page table. This may be a legacy 2-level + * or a PAE 3-level page table. + */ for (i = 0; i < 4; ++i) { hpa_t root = vcpu->arch.mmu.pae_root[i]; @@ -2406,16 +2441,11 @@ static int mmu_alloc_roots(struct kvm_vcpu *vcpu) root_gfn = pdptr >> PAGE_SHIFT; if (mmu_check_root(vcpu, root_gfn)) return 1; - } else if (vcpu->arch.mmu.root_level == 0) - root_gfn = 0; - if (vcpu->arch.mmu.direct_map) { - direct = 1; - root_gfn = i << 30; } spin_lock(&vcpu->kvm->mmu_lock); kvm_mmu_free_some_pages(vcpu); sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30, - PT32_ROOT_LEVEL, direct, + PT32_ROOT_LEVEL, 0, ACC_ALL, NULL); root = __pa(sp->spt); ++sp->root_count; @@ -2427,6 +2457,14 @@ static int mmu_alloc_roots(struct kvm_vcpu *vcpu) return 0; } +static int mmu_alloc_roots(struct kvm_vcpu *vcpu) +{ + if (vcpu->arch.mmu.direct_map) + return mmu_alloc_direct_roots(vcpu); + else + return mmu_alloc_shadow_roots(vcpu); +} + static void mmu_sync_roots(struct kvm_vcpu *vcpu) { int i; |