Implement KVM_TRANSLATE2 for x86 using the default KVM page walker.
Signed-off-by: Nikolas Wipper nikwip@amazon.de --- arch/x86/kvm/x86.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 76 insertions(+)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 27fc71aaa1e4..3bcbad958324 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4683,6 +4683,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) case KVM_CAP_IRQFD_RESAMPLE: case KVM_CAP_MEMORY_FAULT_INFO: case KVM_CAP_X86_GUEST_MODE: + case KVM_CAP_TRANSLATE2: r = 1; break; case KVM_CAP_PRE_FAULT_MEMORY: @@ -12156,6 +12157,81 @@ int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, return 0; }
+/* + * Translate a guest virtual address to a guest physical address. + */ +int kvm_arch_vcpu_ioctl_translate2(struct kvm_vcpu *vcpu, + struct kvm_translation2 *tr) +{ + int idx, set_bit_mode = 0, access = 0; + struct x86_exception exception = { }; + gva_t vaddr = tr->linear_address; + u16 status = 0; + gpa_t gpa; + + if (tr->flags & KVM_TRANSLATE_FLAGS_SET_ACCESSED) + set_bit_mode |= PWALK_SET_ACCESSED; + if (tr->flags & KVM_TRANSLATE_FLAGS_SET_DIRTY) + set_bit_mode |= PWALK_SET_DIRTY; + if (tr->flags & KVM_TRANSLATE_FLAGS_FORCE_SET_ACCESSED) + set_bit_mode |= PWALK_FORCE_SET_ACCESSED; + + if (tr->access & KVM_TRANSLATE_ACCESS_WRITE) + access |= PFERR_WRITE_MASK; + if (tr->access & KVM_TRANSLATE_ACCESS_USER) + access |= PFERR_USER_MASK; + if (tr->access & KVM_TRANSLATE_ACCESS_EXEC) + access |= PFERR_FETCH_MASK; + + vcpu_load(vcpu); + + idx = srcu_read_lock(&vcpu->kvm->srcu); + + /* Even with PAE virtual addresses are still 32-bit */ + if (is_64_bit_mode(vcpu) ? is_noncanonical_address(vaddr, vcpu) : + tr->linear_address >> 32) { + tr->valid = false; + tr->error_code = KVM_TRANSLATE_FAULT_INVALID_GVA; + goto exit; + } + + gpa = kvm_mmu_gva_to_gpa(vcpu, vaddr, access, set_bit_mode, &exception, + &status); + + tr->physical_address = exception.error_code_valid ? exception.gpa_page_fault : gpa; + tr->valid = !exception.error_code_valid; + + /* + * Order is important here: + * - If there are access restrictions those will always be set in the + * error_code + * - If a PTE GPA is unmapped, the present bit in error_code may not + * have been set already + */ + if (exception.flags & KVM_X86_UNMAPPED_PTE_GPA) + tr->error_code = KVM_TRANSLATE_FAULT_INVALID_GPA; + else if (!(exception.error_code & PFERR_PRESENT_MASK)) + tr->error_code = KVM_TRANSLATE_FAULT_NOT_PRESENT; + else if (exception.error_code & PFERR_RSVD_MASK) + tr->error_code = KVM_TRANSLATE_FAULT_RESERVED_BITS; + else if (exception.error_code & (PFERR_USER_MASK | PFERR_WRITE_MASK | + PFERR_FETCH_MASK)) + tr->error_code = KVM_TRANSLATE_FAULT_PRIVILEGE_VIOLATION; + + /* + * exceptions.flags and thus tr->set_bits_succeeded have meaning + * regardless of the success of the page walk. + */ + tr->set_bits_succeeded = tr->flags && + !(status & PWALK_STATUS_READ_ONLY_PTE_GPA); + +exit: + srcu_read_unlock(&vcpu->kvm->srcu, idx); + + vcpu_put(vcpu); + return 0; +} + int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu) { struct fxregs_state *fxsave;