[88/89] KVM: arm64: Introduce KVM_VM_TYPE_ARM_PROTECTED machine type for PVMs

Commit Message

Will Deacon May 19, 2022, 1:42 p.m. UTC

Introduce a new virtual machine type, KVM_VM_TYPE_ARM_PROTECTED, which
specifies that the guest memory pages are to be unmapped from the host
stage-2 by the hypervisor.

Signed-off-by: Will Deacon <[e-mail]>
---
 arch/arm64/include/asm/kvm_pkvm.h |  2 +-
 arch/arm64/kvm/arm.c              |  5 ++++-
 arch/arm64/kvm/mmu.c              |  3 ---
 arch/arm64/kvm/pkvm.c             | 10 +++++++++-
 include/uapi/linux/kvm.h          |  6 ++++++
 5 files changed, 20 insertions(+), 6 deletions(-)

Patch

diff --git a/arch/arm64/include/asm/kvm_pkvm.h b/arch/arm64/include/asm/kvm_pkvm.h
index 062ae2ffbdfb..952e3c3fa32d 100644
--- a/arch/arm64/include/asm/kvm_pkvm.h
+++ b/arch/arm64/include/asm/kvm_pkvm.h
@@ -16,7 +16,7 @@ 
 
 #define HYP_MEMBLOCK_REGIONS 128
 
-int kvm_init_pvm(struct kvm *kvm);
+int kvm_init_pvm(struct kvm *kvm, unsigned long type);
 int kvm_shadow_create(struct kvm *kvm);
 void kvm_shadow_destroy(struct kvm *kvm);
 
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 9c5a935a9a73..26fd69727c81 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -141,11 +141,14 @@  int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 {
 	int ret;
 
+	if (type & ~KVM_VM_TYPE_MASK)
+		return -EINVAL;
+
 	ret = kvm_share_hyp(kvm, kvm + 1);
 	if (ret)
 		return ret;
 
-	ret = kvm_init_pvm(kvm);
+	ret = kvm_init_pvm(kvm, type);
 	if (ret)
 		goto err_unshare_kvm;
 
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 137d4382ed1c..392ff7b2362d 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -652,9 +652,6 @@  int kvm_init_stage2_mmu(struct kvm *kvm, struct kvm_s2_mmu *mmu, unsigned long t
 	u64 mmfr0, mmfr1;
 	u32 phys_shift;
 
-	if (type & ~KVM_VM_TYPE_ARM_IPA_SIZE_MASK)
-		return -EINVAL;
-
 	phys_shift = KVM_VM_TYPE_ARM_IPA_SIZE(type);
 	if (is_protected_kvm_enabled()) {
 		phys_shift = kvm_ipa_limit;
diff --git a/arch/arm64/kvm/pkvm.c b/arch/arm64/kvm/pkvm.c
index 67aad91dc3e5..ebf93ff6a77e 100644
--- a/arch/arm64/kvm/pkvm.c
+++ b/arch/arm64/kvm/pkvm.c
@@ -218,8 +218,16 @@  void kvm_shadow_destroy(struct kvm *kvm)
 	}
 }
 
-int kvm_init_pvm(struct kvm *kvm)
+int kvm_init_pvm(struct kvm *kvm, unsigned long type)
 {
 	mutex_init(&kvm->arch.pkvm.shadow_lock);
+
+	if (!(type & KVM_VM_TYPE_ARM_PROTECTED))
+		return 0;
+
+	if (!is_protected_kvm_enabled())
+		return -EINVAL;
+
+	kvm->arch.pkvm.enabled = true;
 	return 0;
 }
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 91a6fe4e02c0..fdb0289cfecc 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -887,6 +887,12 @@  struct kvm_ppc_resize_hpt {
 #define KVM_VM_TYPE_ARM_IPA_SIZE_MASK	0xffULL
 #define KVM_VM_TYPE_ARM_IPA_SIZE(x)		\
 	((x) & KVM_VM_TYPE_ARM_IPA_SIZE_MASK)
+
+#define KVM_VM_TYPE_ARM_PROTECTED	(1UL << 8)
+
+#define KVM_VM_TYPE_MASK	(KVM_VM_TYPE_ARM_IPA_SIZE_MASK | \
+				 KVM_VM_TYPE_ARM_PROTECTED)
+
 /*
  * ioctls for /dev/kvm fds:
  */