[GIT PULL 02/11] KVM: s390: selftests: add selftest for CMMA migration

Janosch Frank
2023-06-21T15:35:19Z

From: Nico Boehr <nrb@linux.ibm.com>

Add a selftest for CMMA migration on s390.

The tests cover:
- interaction of dirty tracking and migration mode, see my recent patch
"KVM: s390: disable migration mode when dirty tracking is disabled" [1],
- several invalid calls of KVM_S390_GET_CMMA_BITS, for example: invalid
flags, CMMA support off, with/without peeking
- ensure KVM_S390_GET_CMMA_BITS initally reports all pages as dirty,
- ensure KVM_S390_GET_CMMA_BITS properly skips over holes in memslots, but
also non-dirty pages

Note that without the patch at [1] and the small fix in this series, the
selftests will fail.

[1] https://lore.kernel.org/all/20230127140532.230651-2-nrb@linux.ibm.com/

Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-Id: <20230324145424.293889-3-nrb@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
[frankja@linux.ibm.com: squashed
20230606150510.671301-1-nrb@linux.ibm.com / "KVM: s390: selftests:
CMMA: don't run if CMMA not supported"]
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
---
tools/testing/selftests/kvm/Makefile | 1 +
tools/testing/selftests/kvm/s390x/cmma_test.c | 700 ++++++++++++++++++
2 files changed, 701 insertions(+)
create mode 100644 tools/testing/selftests/kvm/s390x/cmma_test.c

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 7a5ff646e7e7..e0e5bf120326 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -163,6 +163,7 @@ TEST_GEN_PROGS_s390x = s390x/memop
TEST_GEN_PROGS_s390x += s390x/resets
TEST_GEN_PROGS_s390x += s390x/sync_regs_test
TEST_GEN_PROGS_s390x += s390x/tprot
+TEST_GEN_PROGS_s390x += s390x/cmma_test
TEST_GEN_PROGS_s390x += demand_paging_test
TEST_GEN_PROGS_s390x += dirty_log_test
TEST_GEN_PROGS_s390x += kvm_create_max_vcpus
diff --git a/tools/testing/selftests/kvm/s390x/cmma_test.c b/tools/testing/selftests/kvm/s390x/cmma_test.c
new file mode 100644
index 000000000000..1d73e78e8fa7
--- /dev/null
+++ b/tools/testing/selftests/kvm/s390x/cmma_test.c
@@ -0,0 +1,700 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Test for s390x CMMA migration
+ *
+ * Copyright IBM Corp. 2023
+ *
+ * Authors:
+ * Nico Boehr <nrb@linux.ibm.com>
+ */
+
+#define _GNU_SOURCE /* for program_invocation_short_name */
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+
+#include "test_util.h"
+#include "kvm_util.h"
+#include "kselftest.h"
+
+#define MAIN_PAGE_COUNT 512
+
+#define TEST_DATA_PAGE_COUNT 512
+#define TEST_DATA_MEMSLOT 1
+#define TEST_DATA_START_GFN 4096
+
+#define TEST_DATA_TWO_PAGE_COUNT 256
+#define TEST_DATA_TWO_MEMSLOT 2
+#define TEST_DATA_TWO_START_GFN 8192
+
+static char cmma_value_buf[MAIN_PAGE_COUNT + TEST_DATA_PAGE_COUNT];
+
+/**
+ * Dirty CMMA attributes of exactly one page in the TEST_DATA memslot,
+ * so use_cmma goes on and the CMMA related ioctls do something.
+ */
+static void guest_do_one_essa(void)
+{
+ asm volatile(
+ /* load TEST_DATA_START_GFN into r1 */
+ " llilf 1,%[start_gfn]\n"
+ /* calculate the address from the gfn */
+ " sllg 1,1,12(0)\n"
+ /* set the first page in TEST_DATA memslot to STABLE */
+ " .insn rrf,0xb9ab0000,2,1,1,0\n"
+ /* hypercall */
+ " diag 0,0,0x501\n"
+ "0: j 0b"
+ :
+ : [start_gfn] "L"(TEST_DATA_START_GFN)
+ : "r1", "r2", "memory", "cc"
+ );
+}
+
+/**
+ * Touch CMMA attributes of all pages in TEST_DATA memslot. Set them to stable
+ * state.
+ */
+static void guest_dirty_test_data(void)
+{
+ asm volatile(
+ /* r1 = TEST_DATA_START_GFN */
+ " xgr 1,1\n"
+ " llilf 1,%[start_gfn]\n"
+ /* r5 = TEST_DATA_PAGE_COUNT */
+ " lghi 5,%[page_count]\n"
+ /* r5 += r1 */
+ "2: agfr 5,1\n"
+ /* r2 = r1 << 12 */
+ "1: sllg 2,1,12(0)\n"
+ /* essa(r4, r2, SET_STABLE) */
+ " .insn rrf,0xb9ab0000,4,2,1,0\n"
+ /* i++ */
+ " agfi 1,1\n"
+ /* if r1 < r5 goto 1 */
+ " cgrjl 1,5,1b\n"
+ /* hypercall */
+ " diag 0,0,0x501\n"
+ "0: j 0b"
+ :
+ : [start_gfn] "L"(TEST_DATA_START_GFN),
+ [page_count] "L"(TEST_DATA_PAGE_COUNT)
+ :
+ /* the counter in our loop over the pages */
+ "r1",
+ /* the calculated page physical address */
+ "r2",
+ /* ESSA output register */
+ "r4",
+ /* last page */
+ "r5",
+ "cc", "memory"
+ );
+}
+
+static struct kvm_vm *create_vm(void)
+{
+ return ____vm_create(VM_MODE_DEFAULT);
+}
+
+static void create_main_memslot(struct kvm_vm *vm)
+{
+ int i;
+
+ vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 0, 0, MAIN_PAGE_COUNT, 0);
+ /* set the array of memslots to zero like __vm_create does */
+ for (i = 0; i < NR_MEM_REGIONS; i++)
+ vm->memslots[i] = 0;
+}
+
+static void create_test_memslot(struct kvm_vm *vm)
+{
+ vm_userspace_mem_region_add(vm,
+ VM_MEM_SRC_ANONYMOUS,
+ TEST_DATA_START_GFN << vm->page_shift,
+ TEST_DATA_MEMSLOT,
+ TEST_DATA_PAGE_COUNT,
+ 0
+ );
+ vm->memslots[MEM_REGION_TEST_DATA] = TEST_DATA_MEMSLOT;
+}
+
+static void create_memslots(struct kvm_vm *vm)
+{
+ /*
+ * Our VM has the following memory layout:
+ * +------+---------------------------+
+ * | GFN | Memslot |
+ * +------+---------------------------+
+ * | 0 | |
+ * | ... | MAIN (Code, Stack, ...) |
+ * | 511 | |
+ * +------+---------------------------+
+ * | 4096 | |
+ * | ... | TEST_DATA |
+ * | 4607 | |
+ * +------+---------------------------+
+ */
+ create_main_memslot(vm);
+ create_test_memslot(vm);
+}
+
+static void finish_vm_setup(struct kvm_vm *vm)
+{
+ struct userspace_mem_region *slot0;
+
+ kvm_vm_elf_load(vm, program_invocation_name);
+
+ slot0 = memslot2region(vm, 0);
+ ucall_init(vm, slot0->region.guest_phys_addr + slot0->region.memory_size);
+
+ kvm_arch_vm_post_create(vm);
+}
+
+static struct kvm_vm *create_vm_two_memslots(void)
+{
+ struct kvm_vm *vm;
+
+ vm = create_vm();
+
+ create_memslots(vm);
+
+ finish_vm_setup(vm);
+
+ return vm;
+}
+
+static void enable_cmma(struct kvm_vm *vm)
+{
+ int r;
+
+ r = __kvm_device_attr_set(vm->fd, KVM_S390_VM_MEM_CTRL, KVM_S390_VM_MEM_ENABLE_CMMA, NULL);
+ TEST_ASSERT(!r, "enabling cmma failed r=%d errno=%d", r, errno);
+}
+
+static void enable_dirty_tracking(struct kvm_vm *vm)
+{
+ vm_mem_region_set_flags(vm, 0, KVM_MEM_LOG_DIRTY_PAGES);
+ vm_mem_region_set_flags(vm, TEST_DATA_MEMSLOT, KVM_MEM_LOG_DIRTY_PAGES);
+}
+
+static int __enable_migration_mode(struct kvm_vm *vm)
+{
+ return __kvm_device_attr_set(vm->fd,
+ KVM_S390_VM_MIGRATION,
+ KVM_S390_VM_MIGRATION_START,
+ NULL
+ );
+}
+
+static void enable_migration_mode(struct kvm_vm *vm)
+{
+ int r = __enable_migration_mode(vm);
+
+ TEST_ASSERT(!r, "enabling migration mode failed r=%d errno=%d", r, errno);
+}
+
+static bool is_migration_mode_on(struct kvm_vm *vm)
+{
+ u64 out;
+ int r;
+
+ r = __kvm_device_attr_get(vm->fd,
+ KVM_S390_VM_MIGRATION,
+ KVM_S390_VM_MIGRATION_STATUS,
+ &out
+ );
+ TEST_ASSERT(!r, "getting migration mode status failed r=%d errno=%d", r, errno);
+ return out;
+}
+
+static int vm_get_cmma_bits(struct kvm_vm *vm, u64 flags, int *errno_out)
+{
+ struct kvm_s390_cmma_log args;
+ int rc;
+
+ errno = 0;
+
+ args = (struct kvm_s390_cmma_log){
+ .start_gfn = 0,
+ .count = sizeof(cmma_value_buf),
+ .flags = flags,
+ .values = (__u64)&cmma_value_buf[0]
+ };
+ rc = __vm_ioctl(vm, KVM_S390_GET_CMMA_BITS, &args);
+
+ *errno_out = errno;
+ return rc;
+}
+
+static void test_get_cmma_basic(void)
+{
+ struct kvm_vm *vm = create_vm_two_memslots();
+ struct kvm_vcpu *vcpu;
+ int rc, errno_out;
+
+ /* GET_CMMA_BITS without CMMA enabled should fail */
+ rc = vm_get_cmma_bits(vm, 0, &errno_out);
+ ASSERT_EQ(rc, -1);
+ ASSERT_EQ(errno_out, ENXIO);
+
+ enable_cmma(vm);
+ vcpu = vm_vcpu_add(vm, 1, guest_do_one_essa);
+
+ vcpu_run(vcpu);
+
+ /* GET_CMMA_BITS without migration mode and without peeking should fail */
+ rc = vm_get_cmma_bits(vm, 0, &errno_out);
+ ASSERT_EQ(rc, -1);
+ ASSERT_EQ(errno_out, EINVAL);
+
+ /* GET_CMMA_BITS without migration mode and with peeking should work */
+ rc = vm_get_cmma_bits(vm, KVM_S390_CMMA_PEEK, &errno_out);
+ ASSERT_EQ(rc, 0);
+ ASSERT_EQ(errno_out, 0);
+
+ enable_dirty_tracking(vm);
+ enable_migration_mode(vm);
+
+ /* GET_CMMA_BITS with invalid flags */
+ rc = vm_get_cmma_bits(vm, 0xfeedc0fe, &errno_out);
+ ASSERT_EQ(rc, -1);
+ ASSERT_EQ(errno_out, EINVAL);
+
+ kvm_vm_free(vm);
+}
+
+static void assert_exit_was_hypercall(struct kvm_vcpu *vcpu)
+{
+ ASSERT_EQ(vcpu->run->exit_reason, 13);
+ ASSERT_EQ(vcpu->run->s390_sieic.icptcode, 4);
+ ASSERT_EQ(vcpu->run->s390_sieic.ipa, 0x8300);
+ ASSERT_EQ(vcpu->run->s390_sieic.ipb, 0x5010000);
+}
+
+static void test_migration_mode(void)
+{
+ struct kvm_vm *vm = create_vm();
+ struct kvm_vcpu *vcpu;
+ u64 orig_psw;
+ int rc;
+
+ /* enabling migration mode on a VM without memory should fail */
+ rc = __enable_migration_mode(vm);
+ ASSERT_EQ(rc, -1);
+ ASSERT_EQ(errno, EINVAL);
+ TEST_ASSERT(!is_migration_mode_on(vm), "migration mode should still be off");
+ errno = 0;
+
+ create_memslots(vm);
+ finish_vm_setup(vm);
+
+ enable_cmma(vm);
+ vcpu = vm_vcpu_add(vm, 1, guest_do_one_essa);
+ orig_psw = vcpu->run->psw_addr;
+
+ /*
+ * Execute one essa instruction in the guest. Otherwise the guest will
+ * not have use_cmm enabled and GET_CMMA_BITS will return no pages.
+ */
+ vcpu_run(vcpu);
+ assert_exit_was_hypercall(vcpu);
+
+ /* migration mode when memslots have dirty tracking off should fail */
+ rc = __enable_migration_mode(vm);
+ ASSERT_EQ(rc, -1);
+ ASSERT_EQ(errno, EINVAL);
+ TEST_ASSERT(!is_migration_mode_on(vm), "migration mode should still be off");
+ errno = 0;
+
+ /* enable dirty tracking */
+ enable_dirty_tracking(vm);
+
+ /* enabling migration mode should work now */
+ rc = __enable_migration_mode(vm);
+ ASSERT_EQ(rc, 0);
+ TEST_ASSERT(is_migration_mode_on(vm), "migration mode should be on");
+ errno = 0;
+
+ /* execute another ESSA instruction to see this goes fine */
+ vcpu->run->psw_addr = orig_psw;
+ vcpu_run(vcpu);
+ assert_exit_was_hypercall(vcpu);
+
+ /*
+ * With migration mode on, create a new memslot with dirty tracking off.
+ * This should turn off migration mode.
+ */
+ TEST_ASSERT(is_migration_mode_on(vm), "migration mode should be on");
+ vm_userspace_mem_region_add(vm,
+ VM_MEM_SRC_ANONYMOUS,
+ TEST_DATA_TWO_START_GFN << vm->page_shift,
+ TEST_DATA_TWO_MEMSLOT,
+ TEST_DATA_TWO_PAGE_COUNT,
+ 0
+ );
+ TEST_ASSERT(!is_migration_mode_on(vm),
+ "creating memslot without dirty tracking turns off migration mode"
+ );
+
+ /* ESSA instructions should still execute fine */
+ vcpu->run->psw_addr = orig_psw;
+ vcpu_run(vcpu);
+ assert_exit_was_hypercall(vcpu);
+
+ /*
+ * Turn on dirty tracking on the new memslot.
+ * It should be possible to turn migration mode back on again.
+ */
+ vm_mem_region_set_flags(vm, TEST_DATA_TWO_MEMSLOT, KVM_MEM_LOG_DIRTY_PAGES);
+ rc = __enable_migration_mode(vm);
+ ASSERT_EQ(rc, 0);
+ TEST_ASSERT(is_migration_mode_on(vm), "migration mode should be on");
+ errno = 0;
+
+ /*
+ * Turn off dirty tracking again, this time with just a flag change.
+ * Again, migration mode should turn off.
+ */
+ TEST_ASSERT(is_migration_mode_on(vm), "migration mode should be on");
+ vm_mem_region_set_flags(vm, TEST_DATA_TWO_MEMSLOT, 0);
+ TEST_ASSERT(!is_migration_mode_on(vm),
+ "disabling dirty tracking should turn off migration mode"
+ );
+
+ /* ESSA instructions should still execute fine */
+ vcpu->run->psw_addr = orig_psw;
+ vcpu_run(vcpu);
+ assert_exit_was_hypercall(vcpu);
+
+ kvm_vm_free(vm);
+}
+
+/**
+ * Given a VM with the MAIN and TEST_DATA memslot, assert that both slots have
+ * CMMA attributes of all pages in both memslots and nothing more dirty.
+ * This has the useful side effect of ensuring nothing is CMMA dirty after this
+ * function.
+ */
+static void assert_all_slots_cmma_dirty(struct kvm_vm *vm)
+{
+ struct kvm_s390_cmma_log args;
+
+ /*
+ * First iteration - everything should be dirty.
+ * Start at the main memslot...
+ */
+ args = (struct kvm_s390_cmma_log){
+ .start_gfn = 0,
+ .count = sizeof(cmma_value_buf),
+ .flags = 0,
+ .values = (__u64)&cmma_value_buf[0]
+ };
+ memset(cmma_value_buf, 0xff, sizeof(cmma_value_buf));
+ vm_ioctl(vm, KVM_S390_GET_CMMA_BITS, &args);
+ ASSERT_EQ(args.count, MAIN_PAGE_COUNT);
+ ASSERT_EQ(args.remaining, TEST_DATA_PAGE_COUNT);
+ ASSERT_EQ(args.start_gfn, 0);
+
+ /* ...and then - after a hole - the TEST_DATA memslot should follow */
+ args = (struct kvm_s390_cmma_log){
+ .start_gfn = MAIN_PAGE_COUNT,
+ .count = sizeof(cmma_value_buf),
+ .flags = 0,
+ .values = (__u64)&cmma_value_buf[0]
+ };
+ memset(cmma_value_buf, 0xff, sizeof(cmma_value_buf));
+ vm_ioctl(vm, KVM_S390_GET_CMMA_BITS, &args);
+ ASSERT_EQ(args.count, TEST_DATA_PAGE_COUNT);
+ ASSERT_EQ(args.start_gfn, TEST_DATA_START_GFN);
+ ASSERT_EQ(args.remaining, 0);
+
+ /* ...and nothing else should be there */
+ args = (struct kvm_s390_cmma_log){
+ .start_gfn = TEST_DATA_START_GFN + TEST_DATA_PAGE_COUNT,
+ .count = sizeof(cmma_value_buf),
+ .flags = 0,
+ .values = (__u64)&cmma_value_buf[0]
+ };
+ memset(cmma_value_buf, 0xff, sizeof(cmma_value_buf));
+ vm_ioctl(vm, KVM_S390_GET_CMMA_BITS, &args);
+ ASSERT_EQ(args.count, 0);
+ ASSERT_EQ(args.start_gfn, 0);
+ ASSERT_EQ(args.remaining, 0);
+}
+
+/**
+ * Given a VM, assert no pages are CMMA dirty.
+ */
+static void assert_no_pages_cmma_dirty(struct kvm_vm *vm)
+{
+ struct kvm_s390_cmma_log args;
+
+ /* If we start from GFN 0 again, nothing should be dirty. */
+ args = (struct kvm_s390_cmma_log){
+ .start_gfn = 0,
+ .count = sizeof(cmma_value_buf),
+ .flags = 0,
+ .values = (__u64)&cmma_value_buf[0]
+ };
+ memset(cmma_value_buf, 0xff, sizeof(cmma_value_buf));
+ vm_ioctl(vm, KVM_S390_GET_CMMA_BITS, &args);
+ if (args.count || args.remaining || args.start_gfn)
+ TEST_FAIL("pages are still dirty start_gfn=0x%llx count=%u remaining=%llu",
+ args.start_gfn,
+ args.count,
+ args.remaining
+ );
+}
+
+static void test_get_inital_dirty(void)
+{
+ struct kvm_vm *vm = create_vm_two_memslots();
+ struct kvm_vcpu *vcpu;
+
+ enable_cmma(vm);
+ vcpu = vm_vcpu_add(vm, 1, guest_do_one_essa);
+
+ /*
+ * Execute one essa instruction in the guest. Otherwise the guest will
+ * not have use_cmm enabled and GET_CMMA_BITS will return no pages.
+ */
+ vcpu_run(vcpu);
+ assert_exit_was_hypercall(vcpu);
+
+ enable_dirty_tracking(vm);
+ enable_migration_mode(vm);
+
+ assert_all_slots_cmma_dirty(vm);
+
+ /* Start from the beginning again and make sure nothing else is dirty */
+ assert_no_pages_cmma_dirty(vm);
+
+ kvm_vm_free(vm);
+}
+
+static void query_cmma_range(struct kvm_vm *vm,
+ u64 start_gfn, u64 gfn_count,
+ struct kvm_s390_cmma_log *res_out)
+{
+ *res_out = (struct kvm_s390_cmma_log){
+ .start_gfn = start_gfn,
+ .count = gfn_count,
+ .flags = 0,
+ .values = (__u64)&cmma_value_buf[0]
+ };
+ memset(cmma_value_buf, 0xff, sizeof(cmma_value_buf));
+ vm_ioctl(vm, KVM_S390_GET_CMMA_BITS, res_out);
+}
+
+/**
+ * Assert the given cmma_log struct that was executed by query_cmma_range()
+ * indicates the first dirty gfn is at first_dirty_gfn and contains exactly
+ * dirty_gfn_count CMMA values.
+ */
+static void assert_cmma_dirty(u64 first_dirty_gfn,
+ u64 dirty_gfn_count,
+ const struct kvm_s390_cmma_log *res)
+{
+ ASSERT_EQ(res->start_gfn, first_dirty_gfn);
+ ASSERT_EQ(res->count, dirty_gfn_count);
+ for (size_t i = 0; i < dirty_gfn_count; i++)
+ ASSERT_EQ(cmma_value_buf[0], 0x0); /* stable state */
+ ASSERT_EQ(cmma_value_buf[dirty_gfn_count], 0xff); /* not touched */
+}
+
+static void test_get_skip_holes(void)
+{
+ size_t gfn_offset;
+ struct kvm_vm *vm = create_vm_two_memslots();
+ struct kvm_s390_cmma_log log;
+ struct kvm_vcpu *vcpu;
+ u64 orig_psw;
+
+ enable_cmma(vm);
+ vcpu = vm_vcpu_add(vm, 1, guest_dirty_test_data);
+
+ orig_psw = vcpu->run->psw_addr;
+
+ /*
+ * Execute some essa instructions in the guest. Otherwise the guest will
+ * not have use_cmm enabled and GET_CMMA_BITS will return no pages.
+ */
+ vcpu_run(vcpu);
+ assert_exit_was_hypercall(vcpu);
+
+ enable_dirty_tracking(vm);
+ enable_migration_mode(vm);
+
+ /* un-dirty all pages */
+ assert_all_slots_cmma_dirty(vm);
+
+ /* Then, dirty just the TEST_DATA memslot */
+ vcpu->run->psw_addr = orig_psw;
+ vcpu_run(vcpu);
+
+ gfn_offset = TEST_DATA_START_GFN;
+ /**
+ * Query CMMA attributes of one page, starting at page 0. Since the
+ * main memslot was not touched by the VM, this should yield the first
+ * page of the TEST_DATA memslot.
+ * The dirty bitmap should now look like this:
+ * 0: not dirty
+ * [0x1, 0x200): dirty
+ */
+ query_cmma_range(vm, 0, 1, &log);
+ assert_cmma_dirty(gfn_offset, 1, &log);
+ gfn_offset++;
+
+ /**
+ * Query CMMA attributes of 32 (0x20) pages past the end of the TEST_DATA
+ * memslot. This should wrap back to the beginning of the TEST_DATA
+ * memslot, page 1.
+ * The dirty bitmap should now look like this:
+ * [0, 0x21): not dirty
+ * [0x21, 0x200): dirty
+ */
+ query_cmma_range(vm, TEST_DATA_START_GFN + TEST_DATA_PAGE_COUNT, 0x20, &log);
+ assert_cmma_dirty(gfn_offset, 0x20, &log);
+ gfn_offset += 0x20;
+
+ /* Skip 32 pages */
+ gfn_offset += 0x20;
+
+ /**
+ * After skipping 32 pages, query the next 32 (0x20) pages.
+ * The dirty bitmap should now look like this:
+ * [0, 0x21): not dirty
+ * [0x21, 0x41): dirty
+ * [0x41, 0x61): not dirty
+ * [0x61, 0x200): dirty
+ */
+ query_cmma_range(vm, gfn_offset, 0x20, &log);
+ assert_cmma_dirty(gfn_offset, 0x20, &log);
+ gfn_offset += 0x20;
+
+ /**
+ * Query 1 page from the beginning of the TEST_DATA memslot. This should
+ * yield page 0x21.
+ * The dirty bitmap should now look like this:
+ * [0, 0x22): not dirty
+ * [0x22, 0x41): dirty
+ * [0x41, 0x61): not dirty
+ * [0x61, 0x200): dirty
+ */
+ query_cmma_range(vm, TEST_DATA_START_GFN, 1, &log);
+ assert_cmma_dirty(TEST_DATA_START_GFN + 0x21, 1, &log);
+ gfn_offset++;
+
+ /**
+ * Query 15 (0xF) pages from page 0x23 in TEST_DATA memslot.
+ * This should yield pages [0x23, 0x33).
+ * The dirty bitmap should now look like this:
+ * [0, 0x22): not dirty
+ * 0x22: dirty
+ * [0x23, 0x33): not dirty
+ * [0x33, 0x41): dirty
+ * [0x41, 0x61): not dirty
+ * [0x61, 0x200): dirty
+ */
+ gfn_offset = TEST_DATA_START_GFN + 0x23;
+ query_cmma_range(vm, gfn_offset, 15, &log);
+ assert_cmma_dirty(gfn_offset, 15, &log);
+
+ /**
+ * Query 17 (0x11) pages from page 0x22 in TEST_DATA memslot.
+ * This should yield page [0x22, 0x33)
+ * The dirty bitmap should now look like this:
+ * [0, 0x33): not dirty
+ * [0x33, 0x41): dirty
+ * [0x41, 0x61): not dirty
+ * [0x61, 0x200): dirty
+ */
+ gfn_offset = TEST_DATA_START_GFN + 0x22;
+ query_cmma_range(vm, gfn_offset, 17, &log);
+ assert_cmma_dirty(gfn_offset, 17, &log);
+
+ /**
+ * Query 25 (0x19) pages from page 0x40 in TEST_DATA memslot.
+ * This should yield page 0x40 and nothing more, since there are more
+ * than 16 non-dirty pages after page 0x40.
+ * The dirty bitmap should now look like this:
+ * [0, 0x33): not dirty
+ * [0x33, 0x40): dirty
+ * [0x40, 0x61): not dirty
+ * [0x61, 0x200): dirty
+ */
+ gfn_offset = TEST_DATA_START_GFN + 0x40;
+ query_cmma_range(vm, gfn_offset, 25, &log);
+ assert_cmma_dirty(gfn_offset, 1, &log);
+
+ /**
+ * Query pages [0x33, 0x40).
+ * The dirty bitmap should now look like this:
+ * [0, 0x61): not dirty
+ * [0x61, 0x200): dirty
+ */
+ gfn_offset = TEST_DATA_START_GFN + 0x33;
+ query_cmma_range(vm, gfn_offset, 0x40 - 0x33, &log);
+ assert_cmma_dirty(gfn_offset, 0x40 - 0x33, &log);
+
+ /**
+ * Query the remaining pages [0x61, 0x200).
+ */
+ gfn_offset = TEST_DATA_START_GFN;
+ query_cmma_range(vm, gfn_offset, TEST_DATA_PAGE_COUNT - 0x61, &log);
+ assert_cmma_dirty(TEST_DATA_START_GFN + 0x61, TEST_DATA_PAGE_COUNT - 0x61, &log);
+
+ assert_no_pages_cmma_dirty(vm);
+}
+
+struct testdef {
+ const char *name;
+ void (*test)(void);
+} testlist[] = {
+ { "migration mode and dirty tracking", test_migration_mode },
+ { "GET_CMMA_BITS: basic calls", test_get_cmma_basic },
+ { "GET_CMMA_BITS: all pages are dirty initally", test_get_inital_dirty },
+ { "GET_CMMA_BITS: holes are skipped", test_get_skip_holes },
+};
+
+/**
+ * The kernel may support CMMA, but the machine may not (i.e. if running as
+ * guest-3).
+ *
+ * In this case, the CMMA capabilities are all there, but the CMMA-related
+ * ioctls fail. To find out whether the machine supports CMMA, create a
+ * temporary VM and then query the CMMA feature of the VM.
+ */
+static int machine_has_cmma(void)
+{
+ struct kvm_vm *vm = create_vm();
+ int r;
+
+ r = !__kvm_has_device_attr(vm->fd, KVM_S390_VM_MEM_CTRL, KVM_S390_VM_MEM_ENABLE_CMMA);
+ kvm_vm_free(vm);
+
+ return r;
+}
+
+int main(int argc, char *argv[])
+{
+ int idx;
+
+ TEST_REQUIRE(kvm_has_cap(KVM_CAP_SYNC_REGS));
+ TEST_REQUIRE(kvm_has_cap(KVM_CAP_S390_CMMA_MIGRATION));
+ TEST_REQUIRE(machine_has_cmma());
+
+ ksft_print_header();
+
+ ksft_set_plan(ARRAY_SIZE(testlist));
+
+ for (idx = 0; idx < ARRAY_SIZE(testlist); idx++) {
+ testlist[idx].test();
+ ksft_test_result_pass("%s\n", testlist[idx].name);
+ }
+
+ ksft_finished(); /* Print results and exit() accordingly */
+}
--
2.41.0