This patch introduces the mem_slot_test test which checks
an VM can have added memory slots up to the limit defined in
KVM_CAP_NR_MEMSLOTS. Then attempt to add one more slot to
verify it fails as expected.
Signed-off-by: Wainer dos Santos Moschetta <wainersm@xxxxxxxxxx>
---
tools/testing/selftests/kvm/.gitignore | 1 +
tools/testing/selftests/kvm/Makefile | 3 +
tools/testing/selftests/kvm/mem_slot_test.c | 85 +++++++++++++++++++++
3 files changed, 89 insertions(+)
create mode 100644 tools/testing/selftests/kvm/mem_slot_test.c
diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore
index 16877c3daabf..127d27188427 100644
--- a/tools/testing/selftests/kvm/.gitignore
+++ b/tools/testing/selftests/kvm/.gitignore
@@ -21,4 +21,5 @@
/demand_paging_test
/dirty_log_test
/kvm_create_max_vcpus
+/mem_slot_test
/steal_time
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 712a2ddd2a27..338b6cdce1a0 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -32,12 +32,14 @@ TEST_GEN_PROGS_x86_64 += clear_dirty_log_test
TEST_GEN_PROGS_x86_64 += demand_paging_test
TEST_GEN_PROGS_x86_64 += dirty_log_test
TEST_GEN_PROGS_x86_64 += kvm_create_max_vcpus
+TEST_GEN_PROGS_x86_64 += mem_slot_test
TEST_GEN_PROGS_x86_64 += steal_time
TEST_GEN_PROGS_aarch64 += clear_dirty_log_test
TEST_GEN_PROGS_aarch64 += demand_paging_test
TEST_GEN_PROGS_aarch64 += dirty_log_test
TEST_GEN_PROGS_aarch64 += kvm_create_max_vcpus
+TEST_GEN_PROGS_aarch64 += mem_slot_test
TEST_GEN_PROGS_aarch64 += steal_time
TEST_GEN_PROGS_s390x = s390x/memop
@@ -46,6 +48,7 @@ TEST_GEN_PROGS_s390x += s390x/sync_regs_test
TEST_GEN_PROGS_s390x += demand_paging_test
TEST_GEN_PROGS_s390x += dirty_log_test
TEST_GEN_PROGS_s390x += kvm_create_max_vcpus
+TEST_GEN_PROGS_s390x += mem_slot_test
TEST_GEN_PROGS += $(TEST_GEN_PROGS_$(UNAME_M))
LIBKVM += $(LIBKVM_$(UNAME_M))
diff --git a/tools/testing/selftests/kvm/mem_slot_test.c b/tools/testing/selftests/kvm/mem_slot_test.c
new file mode 100644
index 000000000000..0588dc2e8e01
--- /dev/null
+++ b/tools/testing/selftests/kvm/mem_slot_test.c
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * mem_slot_test
+ *
+ * Copyright (C) 2020, Red Hat, Inc.
+ *
+ * Test suite for memory region operations.
+ */
+#define _GNU_SOURCE /* for program_invocation_short_name */
+#include <linux/kvm.h>
+#include <sys/mman.h>
+
+#include "test_util.h"
+#include "kvm_util.h"
+
+/*
+ * Test it can be added memory slots up to KVM_CAP_NR_MEMSLOTS, then any
+ * tentative to add further slots should fail.
+ */
+static void test_add_max_slots(void)
+{
+ int ret;
+ struct kvm_userspace_memory_region *kvm_region;
+ struct kvm_vm *vm;
+ uint32_t max_mem_slots;
+ uint32_t mem_reg_flags;
+ uint32_t slot;
+ uint64_t guest_addr;
+ uint64_t mem_reg_npages;
+ uint64_t mem_reg_size;
+
+ max_mem_slots = kvm_check_cap(KVM_CAP_NR_MEMSLOTS);
+ TEST_ASSERT(max_mem_slots > 0,
+ "KVM_CAP_NR_MEMSLOTS should be greater than 0");
+ pr_info("Allowed number of memory slots: %i\n", max_mem_slots);
+
+ vm = vm_create(VM_MODE_DEFAULT, 0, O_RDWR);
+
+ /*
+ * Uses 1MB sized/aligned memory region since this is the minimal
+ * required on s390x.
+ */
+ mem_reg_size = 0x100000;
+ mem_reg_npages = vm_calc_num_guest_pages(VM_MODE_DEFAULT, mem_reg_size);
+ mem_reg_flags = 0;
+
+ guest_addr = 0x0;
+
+ /* Check it can be added memory slots up to the maximum allowed */
+ pr_info("Adding slots 0..%i, each memory region with %ldK size\n",
+ (max_mem_slots - 1), mem_reg_size >> 10);
+ for (slot = 0; slot < max_mem_slots; slot++) {
+ vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
+ guest_addr, slot, mem_reg_npages,
+ mem_reg_flags);
+ guest_addr += mem_reg_size;
+ }
+
+ /* Check it cannot be added memory slots beyond the limit */
+ void *mem = mmap(NULL, mem_reg_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ TEST_ASSERT(mem != MAP_FAILED, "Failed to mmap() host");
+
+ kvm_region = malloc(sizeof(struct kvm_userspace_memory_region));
+ TEST_ASSERT(kvm_region,
+ "Failed to malloc() kvm_userspace_memory_region");
+ kvm_region->slot = slot;
+ kvm_region->flags = mem_reg_flags;
+ kvm_region->guest_phys_addr = guest_addr;
+ kvm_region->userspace_addr = (uint64_t) mem;
+
+ ret = ioctl(vm_get_fd(vm), KVM_SET_USER_MEMORY_REGION, kvm_region);
+ TEST_ASSERT(ret == -1 && errno == EINVAL,
+ "Adding one more memory slot should fail with EINVAL");
+
+ munmap(mem, mem_reg_size);
+ free(kvm_region);
+ kvm_vm_free(vm);
+}
+
+int main(int argc, char *argv[])
+{
+ test_add_max_slots();
+ return 0;
+}
--
2.17.2
