[PATCH v21 12/23] KVM: arm64: Abstract out memory abort handling

[Suzuki K Poulose <suzuki.poulose@arm.com>]

Move the memory abort handling under VM specific s2 operation.

Tested-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
Changes since v19:
 - Drop local variable ret and directly return from if..else for kvm_vm_mem_abort
Changes since v18:
 - Ensure vm_mem_abort handler is always !NULL
---
 arch/arm64/include/asm/kvm_host.h |  2 ++
 arch/arm64/kvm/mmu.c              | 35 ++++++++++++++++++-------------
 2 files changed, 22 insertions(+), 15 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index f01df02dabfe1..871f503e9f164 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -156,6 +156,7 @@ struct kvm_vcpu_ops {
 };
 
 struct kvm_gfn_range;
+struct kvm_s2_fault_desc;
 
 struct kvm_vm_s2_ops {
 	bool (*vm_age_gfn)(struct kvm *kvm, struct kvm_gfn_range *range);
@@ -166,6 +167,7 @@ struct kvm_vm_s2_ops {
 	void (*vm_stage2_unmap_range)(struct kvm_s2_mmu *mmu,
 				      phys_addr_t start, u64 size,
 				      bool may_block);
+	int (*vm_mem_abort)(const struct kvm_s2_fault_desc *s2fd);
 };
 
 struct kvm_s2_mmu {
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 8fe7178c40bec..8e092efdf0825 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -1743,7 +1743,7 @@ struct kvm_s2_fault_vma_info {
 	bool		map_non_cacheable;
 };
 
-static int pkvm_mem_abort(const struct kvm_s2_fault_desc *s2fd)
+static int protected_vm_mem_abort(const struct kvm_s2_fault_desc *s2fd)
 {
 	unsigned int flags = FOLL_HWPOISON | FOLL_LONGTERM | FOLL_WRITE;
 	struct kvm_vcpu *vcpu = s2fd->vcpu;
@@ -2181,6 +2181,20 @@ static int user_mem_abort(const struct kvm_s2_fault_desc *s2fd)
 	return kvm_s2_fault_map(s2fd, &s2vi, prot, memcache);
 }
 
+static int kvm_vm_mem_abort(const struct kvm_s2_fault_desc *s2fd)
+{
+	struct kvm_vcpu *vcpu = s2fd->vcpu;
+
+	VM_WARN_ON_ONCE(kvm_vcpu_trap_is_permission_fault(vcpu) &&
+			!kvm_is_write_fault(vcpu) &&
+			!kvm_vcpu_trap_is_exec_fault(vcpu));
+
+	if (kvm_slot_has_gmem(s2fd->memslot))
+		return gmem_abort(s2fd);
+	else
+		return user_mem_abort(s2fd);
+}
+
 /* Resolve the access fault by making the page young again. */
 static void handle_access_fault(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa)
 {
@@ -2450,19 +2464,7 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu)
 		.hva		= hva,
 	};
 
-	if (kvm_vm_is_protected(kvm)) {
-		ret = pkvm_mem_abort(&s2fd);
-	} else {
-		VM_WARN_ON_ONCE(kvm_vcpu_trap_is_permission_fault(vcpu) &&
-				!write_fault &&
-				!kvm_vcpu_trap_is_exec_fault(vcpu));
-
-		if (kvm_slot_has_gmem(memslot))
-			ret = gmem_abort(&s2fd);
-		else
-			ret = user_mem_abort(&s2fd);
-	}
-
+	ret = kvm->arch.vm_s2_ops->vm_mem_abort(&s2fd);
 	if (ret == 0)
 		ret = 1;
 out:
@@ -2857,6 +2859,7 @@ static const struct kvm_vm_s2_ops protected_pkvm_vm_s2_ops = {
 	 * .vm_test_age_gfn
 	 * .vm_stage2_unmap_range
 	 */
+	.vm_mem_abort			= protected_vm_mem_abort,
 };
 
 static const struct kvm_vm_s2_ops pkvm_vm_s2_ops = {
@@ -2865,6 +2868,7 @@ static const struct kvm_vm_s2_ops pkvm_vm_s2_ops = {
 	.vm_age_gfn			= kvm_vm_age_gfn,
 	.vm_test_age_gfn		= kvm_vm_test_age_gfn,
 	.vm_stage2_unmap_range		= kvm_vm_stage2_unmap_range,
+	.vm_mem_abort			= kvm_vm_mem_abort,
 };
 
 static const struct kvm_vm_s2_ops kvm_default_vm_s2_ops = {
@@ -2873,6 +2877,7 @@ static const struct kvm_vm_s2_ops kvm_default_vm_s2_ops = {
 	.vm_age_gfn			= kvm_vm_age_gfn,
 	.vm_test_age_gfn		= kvm_vm_test_age_gfn,
 	.vm_stage2_unmap_range		= kvm_vm_stage2_unmap_range,
+	.vm_mem_abort			= kvm_vm_mem_abort,
 };
 
 #define KVM_VM_S2_OPS(flavor, ops)		\
@@ -2889,7 +2894,7 @@ static int kvm_vm_init_vm_s2_ops(struct kvm *kvm)
 	BUILD_BUG_ON(ARRAY_SIZE(arm64_vm_s2_ops) != VM_FLAVOR_MAX);
 
 	kvm->arch.vm_s2_ops = arm64_vm_s2_ops[kvm->arch.vm_flavor];
-	if (WARN_ON(!kvm->arch.vm_s2_ops))
+	if (WARN_ON(!kvm->arch.vm_s2_ops || !kvm->arch.vm_s2_ops->vm_mem_abort))
 		return -EINVAL;
 	return 0;
 }
-- 
2.43.0