[PATCH V6 4/7] KVM: selftests: add support for protected vm_vaddr_* allocations

Peter Gonda
2023-01-10T17:51:39Z

From: Michael Roth <michael.roth@amd.com>

Test programs may wish to allocate shared vaddrs for things like
sharing memory with the guest. Since protected vms will have their
memory encrypted by default an interface is needed to explicitly
request shared pages.

Implement this by splitting the common code out from vm_vaddr_alloc()
and introducing a new vm_vaddr_alloc_shared().

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Vishal Annapurve <vannapurve@google.com>
Cc: Ackerley Tng <ackerleytng@google.com>
cc: Andrew Jones <andrew.jones@linux.dev>
Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Peter Gonda <pgonda@google.com>
---
.../selftests/kvm/include/kvm_util_base.h | 1 +
tools/testing/selftests/kvm/lib/kvm_util.c | 21 +++++++++++++++----
2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h
index f84d7777d5ca..5f3150ecfbbf 100644
--- a/tools/testing/selftests/kvm/include/kvm_util_base.h
+++ b/tools/testing/selftests/kvm/include/kvm_util_base.h
@@ -435,6 +435,7 @@ vm_vaddr_t vm_vaddr_unused_gap(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_mi
vm_vaddr_t vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min);
vm_vaddr_t __vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min,
enum kvm_mem_region_type type);
+vm_vaddr_t vm_vaddr_alloc_shared(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min);
vm_vaddr_t vm_vaddr_alloc_pages(struct kvm_vm *vm, int nr_pages);
vm_vaddr_t __vm_vaddr_alloc_page(struct kvm_vm *vm,
enum kvm_mem_region_type type);
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index ba771c2d949d..0d0a7ad7632d 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -1305,15 +1305,17 @@ vm_vaddr_t vm_vaddr_unused_gap(struct kvm_vm *vm, size_t sz,
return pgidx_start * vm->page_size;
}

-vm_vaddr_t __vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min,
- enum kvm_mem_region_type type)
+static vm_vaddr_t ____vm_vaddr_alloc(struct kvm_vm *vm, size_t sz,
+ vm_vaddr_t vaddr_min,
+ enum kvm_mem_region_type type,
+ bool encrypt)
{
uint64_t pages = (sz >> vm->page_shift) + ((sz % vm->page_size) != 0);

virt_pgd_alloc(vm);
- vm_paddr_t paddr = vm_phy_pages_alloc(vm, pages,
+ vm_paddr_t paddr = _vm_phy_pages_alloc(vm, pages,
KVM_UTIL_MIN_PFN * vm->page_size,
- vm->memslots[type]);
+ vm->memslots[type], encrypt);

/*
* Find an unused range of virtual page addresses of at least
@@ -1333,6 +1335,17 @@ vm_vaddr_t __vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min,
return vaddr_start;
}

+vm_vaddr_t __vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min,
+ enum kvm_mem_region_type type)
+{
+ return ____vm_vaddr_alloc(vm, sz, vaddr_min, type, vm->protected);
+}
+
+vm_vaddr_t vm_vaddr_alloc_shared(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min)
+{
+ return ____vm_vaddr_alloc(vm, sz, vaddr_min, MEM_REGION_TEST_DATA, false);
+}
+
/*
* VM Virtual Address Allocate
*
--
2.39.0.314.g84b9a713c41-goog