1 files changed, 312 insertions, 0 deletions
diff --git a/tools/testing/selftests/mm/va_high_addr_switch.c b/tools/testing/selftests/mm/va_high_addr_switch.c
new file mode 100644
index 000000000000..cfbc501290d3
--- /dev/null
+++ b/tools/testing/selftests/mm/va_high_addr_switch.c
@@ -0,0 +1,312 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * Authors: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
+ * Authors: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
+ */
+
+#include <stdio.h>
+#include <sys/mman.h>
+#include <string.h>
+
+#include "../kselftest.h"
+
+#ifdef __powerpc64__
+#define PAGE_SIZE	(64 << 10)
+/*
+ * This will work with 16M and 2M hugepage size
+ */
+#define HUGETLB_SIZE	(16 << 20)
+#elif __aarch64__
+/*
+ * The default hugepage size for 64k base pagesize
+ * is 512MB.
+ */
+#define PAGE_SIZE	(64 << 10)
+#define HUGETLB_SIZE	(512 << 20)
+#else
+#define PAGE_SIZE	(4 << 10)
+#define HUGETLB_SIZE	(2 << 20)
+#endif
+
+/*
+ * The hint addr value is used to allocate addresses
+ * beyond the high address switch boundary.
+ */
+
+#define ADDR_MARK_128TB	(1UL << 47)
+#define ADDR_MARK_256TB	(1UL << 48)
+
+#define HIGH_ADDR_128TB	((void *) (1UL << 48))
+#define HIGH_ADDR_256TB	((void *) (1UL << 49))
+
+#define LOW_ADDR	((void *) (1UL << 30))
+
+#ifdef __aarch64__
+#define ADDR_SWITCH_HINT ADDR_MARK_256TB
+#define HIGH_ADDR	 HIGH_ADDR_256TB
+#else
+#define ADDR_SWITCH_HINT ADDR_MARK_128TB
+#define HIGH_ADDR	 HIGH_ADDR_128TB
+#endif
+
+struct testcase {
+	void *addr;
+	unsigned long size;
+	unsigned long flags;
+	const char *msg;
+	unsigned int low_addr_required:1;
+	unsigned int keep_mapped:1;
+};
+
+static struct testcase testcases[] = {
+	{
+		/*
+		 * If stack is moved, we could possibly allocate
+		 * this at the requested address.
+		 */
+		.addr = ((void *)(ADDR_SWITCH_HINT - PAGE_SIZE)),
+		.size = PAGE_SIZE,
+		.flags = MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(ADDR_SWITCH_HINT - PAGE_SIZE, PAGE_SIZE)",
+		.low_addr_required = 1,
+	},
+	{
+		/*
+		 * Unless MAP_FIXED is specified, allocation based on hint
+		 * addr is never at requested address or above it, which is
+		 * beyond high address switch boundary in this case. Instead,
+		 * a suitable allocation is found in lower address space.
+		 */
+		.addr = ((void *)(ADDR_SWITCH_HINT - PAGE_SIZE)),
+		.size = 2 * PAGE_SIZE,
+		.flags = MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(ADDR_SWITCH_HINT - PAGE_SIZE, (2 * PAGE_SIZE))",
+		.low_addr_required = 1,
+	},
+	{
+		/*
+		 * Exact mapping at high address switch boundary, should
+		 * be obtained even without MAP_FIXED as area is free.
+		 */
+		.addr = ((void *)(ADDR_SWITCH_HINT)),
+		.size = PAGE_SIZE,
+		.flags = MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(ADDR_SWITCH_HINT, PAGE_SIZE)",
+		.keep_mapped = 1,
+	},
+	{
+		.addr = (void *)(ADDR_SWITCH_HINT),
+		.size = 2 * PAGE_SIZE,
+		.flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED,
+		.msg = "mmap(ADDR_SWITCH_HINT, 2 * PAGE_SIZE, MAP_FIXED)",
+	},
+	{
+		.addr = NULL,
+		.size = 2 * PAGE_SIZE,
+		.flags = MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(NULL)",
+		.low_addr_required = 1,
+	},
+	{
+		.addr = LOW_ADDR,
+		.size = 2 * PAGE_SIZE,
+		.flags = MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(LOW_ADDR)",
+		.low_addr_required = 1,
+	},
+	{
+		.addr = HIGH_ADDR,
+		.size = 2 * PAGE_SIZE,
+		.flags = MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(HIGH_ADDR)",
+		.keep_mapped = 1,
+	},
+	{
+		.addr = HIGH_ADDR,
+		.size = 2 * PAGE_SIZE,
+		.flags = MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(HIGH_ADDR) again",
+		.keep_mapped = 1,
+	},
+	{
+		.addr = HIGH_ADDR,
+		.size = 2 * PAGE_SIZE,
+		.flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED,
+		.msg = "mmap(HIGH_ADDR, MAP_FIXED)",
+	},
+	{
+		.addr = (void *) -1,
+		.size = 2 * PAGE_SIZE,
+		.flags = MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(-1)",
+		.keep_mapped = 1,
+	},
+	{
+		.addr = (void *) -1,
+		.size = 2 * PAGE_SIZE,
+		.flags = MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(-1) again",
+	},
+	{
+		.addr = ((void *)(ADDR_SWITCH_HINT - PAGE_SIZE)),
+		.size = PAGE_SIZE,
+		.flags = MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(ADDR_SWITCH_HINT - PAGE_SIZE, PAGE_SIZE)",
+		.low_addr_required = 1,
+	},
+	{
+		.addr = (void *)(ADDR_SWITCH_HINT - PAGE_SIZE),
+		.size = 2 * PAGE_SIZE,
+		.flags = MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(ADDR_SWITCH_HINT - PAGE_SIZE, 2 * PAGE_SIZE)",
+		.low_addr_required = 1,
+		.keep_mapped = 1,
+	},
+	{
+		.addr = (void *)(ADDR_SWITCH_HINT - PAGE_SIZE / 2),
+		.size = 2 * PAGE_SIZE,
+		.flags = MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(ADDR_SWITCH_HINT - PAGE_SIZE/2 , 2 * PAGE_SIZE)",
+		.low_addr_required = 1,
+		.keep_mapped = 1,
+	},
+	{
+		.addr = ((void *)(ADDR_SWITCH_HINT)),
+		.size = PAGE_SIZE,
+		.flags = MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(ADDR_SWITCH_HINT, PAGE_SIZE)",
+	},
+	{
+		.addr = (void *)(ADDR_SWITCH_HINT),
+		.size = 2 * PAGE_SIZE,
+		.flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED,
+		.msg = "mmap(ADDR_SWITCH_HINT, 2 * PAGE_SIZE, MAP_FIXED)",
+	},
+};
+
+static struct testcase hugetlb_testcases[] = {
+	{
+		.addr = NULL,
+		.size = HUGETLB_SIZE,
+		.flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(NULL, MAP_HUGETLB)",
+		.low_addr_required = 1,
+	},
+	{
+		.addr = LOW_ADDR,
+		.size = HUGETLB_SIZE,
+		.flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(LOW_ADDR, MAP_HUGETLB)",
+		.low_addr_required = 1,
+	},
+	{
+		.addr = HIGH_ADDR,
+		.size = HUGETLB_SIZE,
+		.flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(HIGH_ADDR, MAP_HUGETLB)",
+		.keep_mapped = 1,
+	},
+	{
+		.addr = HIGH_ADDR,
+		.size = HUGETLB_SIZE,
+		.flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(HIGH_ADDR, MAP_HUGETLB) again",
+		.keep_mapped = 1,
+	},
+	{
+		.addr = HIGH_ADDR,
+		.size = HUGETLB_SIZE,
+		.flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED,
+		.msg = "mmap(HIGH_ADDR, MAP_FIXED | MAP_HUGETLB)",
+	},
+	{
+		.addr = (void *) -1,
+		.size = HUGETLB_SIZE,
+		.flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(-1, MAP_HUGETLB)",
+		.keep_mapped = 1,
+	},
+	{
+		.addr = (void *) -1,
+		.size = HUGETLB_SIZE,
+		.flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(-1, MAP_HUGETLB) again",
+	},
+	{
+		.addr = (void *)(ADDR_SWITCH_HINT - PAGE_SIZE),
+		.size = 2 * HUGETLB_SIZE,
+		.flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS,
+		.msg = "mmap(ADDR_SWITCH_HINT - PAGE_SIZE, 2*HUGETLB_SIZE, MAP_HUGETLB)",
+		.low_addr_required = 1,
+		.keep_mapped = 1,
+	},
+	{
+		.addr = (void *)(ADDR_SWITCH_HINT),
+		.size = 2 * HUGETLB_SIZE,
+		.flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED,
+		.msg = "mmap(ADDR_SWITCH_HINT , 2*HUGETLB_SIZE, MAP_FIXED | MAP_HUGETLB)",
+	},
+};
+
+static int run_test(struct testcase *test, int count)
+{
+	void *p;
+	int i, ret = KSFT_PASS;
+
+	for (i = 0; i < count; i++) {
+		struct testcase *t = test + i;
+
+		p = mmap(t->addr, t->size, PROT_READ | PROT_WRITE, t->flags, -1, 0);
+
+		printf("%s: %p - ", t->msg, p);
+
+		if (p == MAP_FAILED) {
+			printf("FAILED\n");
+			ret = KSFT_FAIL;
+			continue;
+		}
+
+		if (t->low_addr_required && p >= (void *)(ADDR_SWITCH_HINT)) {
+			printf("FAILED\n");
+			ret = KSFT_FAIL;
+		} else {
+			/*
+			 * Do a dereference of the address returned so that we catch
+			 * bugs in page fault handling
+			 */
+			memset(p, 0, t->size);
+			printf("OK\n");
+		}
+		if (!t->keep_mapped)
+			munmap(p, t->size);
+	}
+
+	return ret;
+}
+
+static int supported_arch(void)
+{
+#if defined(__powerpc64__)
+	return 1;
+#elif defined(__x86_64__)
+	return 1;
+#elif defined(__aarch64__)
+	return getpagesize() == PAGE_SIZE;
+#else
+	return 0;
+#endif
+}
+
+int main(int argc, char **argv)
+{
+	int ret;
+
+	if (!supported_arch())
+		return KSFT_SKIP;
+
+	ret = run_test(testcases, ARRAY_SIZE(testcases));
+	if (argc == 2 && !strcmp(argv[1], "--run-hugetlb"))
+		ret = run_test(hugetlb_testcases, ARRAY_SIZE(hugetlb_testcases));
+	return ret;
+}