selftests: kvm: Add vm_get_fd() in kvm_util

Introduces the vm_get_fd() function in kvm_util which returns
the VM file descriptor.
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200410231707.7128-8-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

tools/testing/selftests/kvm/include/kvm_util.h

@@ -256,6 +256,7 @@ bool vm_is_unrestricted_guest(struct kvm_vm *vm);
 unsigned int vm_get_page_size(struct kvm_vm *vm);
 unsigned int vm_get_page_shift(struct kvm_vm *vm);
 unsigned int vm_get_max_gfn(struct kvm_vm *vm);
+int vm_get_fd(struct kvm_vm *vm);
 
 unsigned int vm_calc_num_guest_pages(enum vm_guest_mode mode, size_t size);
 unsigned int vm_num_host_pages(enum vm_guest_mode mode, unsigned int num_guest_pages);

tools/testing/selftests/kvm/lib/kvm_util.c

@@ -1739,6 +1739,11 @@ unsigned int vm_get_max_gfn(struct kvm_vm *vm)
 	return vm->max_gfn;
 }
 
+int vm_get_fd(struct kvm_vm *vm)
+{
+	return vm->fd;
+}
+
 static unsigned int vm_calc_num_pages(unsigned int num_pages,
 				      unsigned int page_shift,
 				      unsigned int new_page_shift,