path: root/tools/testing/selftests/kvm/lib/kvm_util.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * tools/testing/selftests/kvm/lib/kvm_util.c
 *
 * Copyright (C) 2018, Google LLC.
 */

#include "test_util.h"
#include "kvm_util.h"
#include "kvm_util_internal.h"

#include <assert.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <linux/kernel.h>

#define KVM_UTIL_PGS_PER_HUGEPG 512
#define KVM_UTIL_MIN_PFN	2

/* Aligns x up to the next multiple of size. Size must be a power of 2. */
static void *align(void *x, size_t size)
{
	size_t mask = size - 1;
	TEST_ASSERT(size != 0 && !(size & (size - 1)),
		    "size not a power of 2: %lu", size);
	return (void *) (((size_t) x + mask) & ~mask);
}

/*
 * Capability
 *
 * Input Args:
 *   cap - Capability
 *
 * Output Args: None
 *
 * Return:
 *   On success, the Value corresponding to the capability (KVM_CAP_*)
 *   specified by the value of cap.  On failure a TEST_ASSERT failure
 *   is produced.
 *
 * Looks up and returns the value corresponding to the capability
 * (KVM_CAP_*) given by cap.
 */
int kvm_check_cap(long cap)
{
	int ret;
	int kvm_fd;

	kvm_fd = open(KVM_DEV_PATH, O_RDONLY);
	if (kvm_fd < 0)
		exit(KSFT_SKIP);

	ret = ioctl(kvm_fd, KVM_CHECK_EXTENSION, cap);
	TEST_ASSERT(ret != -1, "KVM_CHECK_EXTENSION IOCTL failed,\n"
		"  rc: %i errno: %i", ret, errno);

	close(kvm_fd);

	return ret;
}

/* VM Enable Capability
 *
 * Input Args:
 *   vm - Virtual Machine
 *   cap - Capability
 *
 * Output Args: None
 *
 * Return: On success, 0. On failure a TEST_ASSERT failure is produced.
 *
 * Enables a capability (KVM_CAP_*) on the VM.
 */
int vm_enable_cap(struct kvm_vm *vm, struct kvm_enable_cap *cap)
{
	int ret;

	ret = ioctl(vm->fd, KVM_ENABLE_CAP, cap);
	TEST_ASSERT(ret == 0, "KVM_ENABLE_CAP IOCTL failed,\n"
		"  rc: %i errno: %i", ret, errno);

	return ret;
}

static void vm_open(struct kvm_vm *vm, int perm, unsigned long type)
{
	vm->kvm_fd = open(KVM_DEV_PATH, perm);
	if (vm->kvm_fd < 0)
		exit(KSFT_SKIP);

	if (!kvm_check_cap(KVM_CAP_IMMEDIATE_EXIT)) {
		fprintf(stderr, "immediate_exit not available, skipping test\n");
		exit(KSFT_SKIP);
	}

	vm->fd = ioctl(vm->kvm_fd, KVM_CREATE_VM, type);
	TEST_ASSERT(vm->fd >= 0, "KVM_CREATE_VM ioctl failed, "
		"rc: %i errno: %i", vm->fd, errno);
}

const char * const vm_guest_mode_string[] = {
	"PA-bits:52, VA-bits:48, 4K pages",
	"PA-bits:52, VA-bits:48, 64K pages",
	"PA-bits:48, VA-bits:48, 4K pages",
	"PA-bits:48, VA-bits:48, 64K pages",
	"PA-bits:40, VA-bits:48, 4K pages",
	"PA-bits:40, VA-bits:48, 64K pages",
};
_Static_assert(sizeof(vm_guest_mode_string)/sizeof(char *) == NUM_VM_MODES,
	       "Missing new mode strings?");

/*
 * VM Create
 *
 * Input Args:
 *   mode - VM Mode (e.g. VM_MODE_P52V48_4K)
 *   phy_pages - Physical memory pages
 *   perm - permission
 *
 * Output Args: None
 *
 * Return:
 *   Pointer to opaque structure that describes the created VM.
 *
 * Creates a VM with the mode specified by mode (e.g. VM_MODE_P52V48_4K).
 * When phy_pages is non-zero, a memory region of phy_pages physical pages
 * is created and mapped starting at guest physical address 0.  The file
 * descriptor to control the created VM is created with the permissions
 * given by perm (e.g. O_RDWR).
 */
struct kvm_vm *_vm_create(enum vm_guest_mode mode, uint64_t phy_pages,
			  int perm, unsigned long type)
{
	struct kvm_vm *vm;

	vm = calloc(1, sizeof(*vm));
	TEST_ASSERT(vm != NULL, "Insufficient Memory");

	vm->mod