[PATCH v15 18/23] KVM: selftests: Add helpers to init TDX memory and finalize VM

[Lisa Wang <wyihan@google.com>]

From: Ackerley Tng <ackerleytng@google.com>

TDX protected memory needs to be measured and encrypted before it can be
used by the guest. Traverse the VM's memory regions and initialize all
the protected ranges by calling KVM_TDX_INIT_MEM_REGION.

Once all the memory is initialized, the VM can be finalized by calling
KVM_TDX_FINALIZE_VM.

Co-developed-by: Erdem Aktas <erdemaktas@google.com>
Signed-off-by: Erdem Aktas <erdemaktas@google.com>
Co-developed-by: Sagi Shahar <sagis@google.com>
Signed-off-by: Sagi Shahar <sagis@google.com>
Co-developed-by: Lisa Wang <wyihan@google.com>
Signed-off-by: Lisa Wang <wyihan@google.com>
Signed-off-by: Ackerley Tng <ackerleytng@google.com>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
---
 .../selftests/kvm/include/x86/tdx/tdx_util.h       |  2 +
 tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c | 62 ++++++++++++++++++++++
 2 files changed, 64 insertions(+)

diff --git a/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h b/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
index f36cddbd045c..dcfc62ffbaeb 100644
--- a/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
+++ b/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
@@ -73,4 +73,6 @@ void tdx_vm_load_common_boot_parameters(struct kvm_vm *vm);
 void tdx_vcpu_load_boot_parameters(struct kvm_vm *vm, struct kvm_vcpu *vcpu);
 void tdx_vcpu_set_entry_point(struct kvm_vcpu *vcpu, void *guest_code);
 
+void tdx_vm_finalize(struct kvm_vm *vm);
+
 #endif /* SELFTESTS_TDX_TDX_UTIL_H */
diff --git a/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c b/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c
index 5f10a7c1455d..b8e1f848cf54 100644
--- a/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c
+++ b/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-only
 
+#include <linux/align.h>
 #include <linux/sizes.h>
 
 #include "processor.h"
@@ -228,3 +229,64 @@ void tdx_init_vm(struct kvm_vm *vm)
 
 	free(init_vm);
 }
+
+static void tdx_init_mem_region(struct kvm_vm *vm, void *source_pages,
+				u64 gpa, u64 size)
+{
+	u32 flags = KVM_TDX_MEASURE_MEMORY_REGION;
+	struct kvm_tdx_init_mem_region mem_region = {
+		.source_addr = (u64)source_pages,
+		.gpa = gpa,
+		.nr_pages = size / PAGE_SIZE,
+	};
+	struct kvm_vcpu *vcpu;
+
+	vcpu = list_first_entry_or_null(&vm->vcpus, struct kvm_vcpu, list);
+
+	TEST_ASSERT(size && IS_ALIGNED(size, PAGE_SIZE),
+		    "Cannot add partial pages to the guest memory.\n");
+	TEST_ASSERT(IS_ALIGNED((u64)source_pages, PAGE_SIZE),
+		    "Source memory buffer is not page aligned\n");
+	tdx_vcpu_ioctl(vcpu, KVM_TDX_INIT_MEM_REGION, flags, &mem_region);
+}
+
+static void tdx_load_private_memory(struct kvm_vm *vm)
+{
+	struct userspace_mem_region *region;
+	int ctr;
+
+	hash_for_each(vm->regions.slot_hash, ctr, region, slot_node) {
+		const struct sparsebit *protected_pages = region->protected_phy_pages;
+		const gpa_t gpa_base = region->region.guest_phys_addr;
+		const u64 hva_base = region->region.userspace_addr;
+		const sparsebit_idx_t lowest_page_in_region = gpa_base >> vm->page_shift;
+		void *source_pages = NULL;
+		sparsebit_idx_t i, j;
+
+		if (!sparsebit_any_set(protected_pages))
+			continue;
+
+		TEST_ASSERT(region->region.guest_memfd != -1,
+			    "TD private memory must be backed by guest_memfd");
+
+		sparsebit_for_each_set_range(protected_pages, i, j) {
+			const u64 size_to_load = (j - i + 1) * vm->page_size;
+			const u64 offset =
+				(i - lowest_page_in_region) * vm->page_size;
+			const u64 hva = hva_base + offset;
+			const u64 gpa = gpa_base + offset;
+
+			if (!kvm_has_gmem_attributes)
+				source_pages = (void *)hva;
+
+			vm_mem_set_private(vm, gpa, size_to_load);
+			tdx_init_mem_region(vm, source_pages, gpa, size_to_load);
+		}
+	}
+}
+
+void tdx_vm_finalize(struct kvm_vm *vm)
+{
+	tdx_load_private_memory(vm);
+	tdx_vm_ioctl(vm, KVM_TDX_FINALIZE_VM, 0, NULL);
+}

-- 
2.56.0.rc1.315.gc6ed9934b7-goog