Index: head/tests/sys/vm/Makefile
===================================================================
--- head/tests/sys/vm/Makefile
+++ head/tests/sys/vm/Makefile
@@ -2,6 +2,6 @@
 
 TESTSDIR=	${TESTSBASE}/sys/vm
 
-TAP_TESTS_C+=	mmap_test
+ATF_TESTS_C+=	mmap_test
 
 .include <bsd.test.mk>
Index: head/tests/sys/vm/mmap_test.c
===================================================================
--- head/tests/sys/vm/mmap_test.c
+++ head/tests/sys/vm/mmap_test.c
@@ -29,16 +29,14 @@
 #include <sys/param.h>
 #include <sys/mman.h>
 #include <sys/sysctl.h>
-#include <sys/types.h>
 
+#include <atf-c.h>
 #include <errno.h>
-#include <stdio.h>
-#include <string.h>
 
 static const struct {
 	void	*addr;
 	int	ok[2];	/* Depending on security.bsd.map_at_zero {0, !=0}. */
-} tests[] = {
+} map_at_zero_tests[] = {
 	{ (void *)0,			{ 0, 1 } }, /* Test sysctl. */
 	{ (void *)1,			{ 0, 0 } },
 	{ (void *)(PAGE_SIZE - 1),	{ 0, 0 } },
@@ -52,54 +50,43 @@
 
 #define	MAP_AT_ZERO	"security.bsd.map_at_zero"
 
-int
-main(void)
+ATF_TC_WITHOUT_HEAD(mmap__map_at_zero);
+ATF_TC_BODY(mmap__map_at_zero, tc)
 {
 	void *p;
 	size_t len;
-	int i, error, mib[3], map_at_zero;
-
-	error = 0;
-
-	/* Get the current sysctl value of security.bsd.map_at_zero. */
-	len = sizeof(mib) / sizeof(*mib);
-	if (sysctlnametomib(MAP_AT_ZERO, mib, &len) == -1) {
-		printf("1..0 # SKIP: sysctlnametomib(\"%s\") failed: %s\n",
-		    MAP_AT_ZERO, strerror(errno));
-		return (0);
-	}
+	unsigned int i;
+	int map_at_zero;
 
 	len = sizeof(map_at_zero);
-	if (sysctl(mib, 3, &map_at_zero, &len, NULL, 0) == -1) {
-		printf("1..0 # SKIP: sysctl for %s failed: %s\n", MAP_AT_ZERO,
+	if (sysctlbyname(MAP_AT_ZERO, &map_at_zero, &len, NULL, 0) == -1) {
+		atf_tc_skip("sysctl for %s failed: %s\n", MAP_AT_ZERO,
 		    strerror(errno));
-		return (0);
+		return;
 	}
 
 	/* Normalize to 0 or 1 for array access. */
 	map_at_zero = !!map_at_zero;
 
-	printf("1..%zu\n", nitems(tests));
-	for (i = 0; i < (int)nitems(tests); i++) {
-		p = mmap((void *)tests[i].addr, PAGE_SIZE,
+	for (i = 0; i < nitems(map_at_zero_tests); i++) {
+		p = mmap((void *)map_at_zero_tests[i].addr, PAGE_SIZE,
 		    PROT_READ | PROT_WRITE | PROT_EXEC, MAP_ANON | MAP_FIXED,
 		    -1, 0);
 		if (p == MAP_FAILED) {
-			if (tests[i].ok[map_at_zero] != 0)
-				error++;
-			printf("%sok %d # mmap(%p, ...) failed\n",
-			    tests[i].ok[map_at_zero] == 0 ? "" : "not ",
-			    i + 1,
-			    tests[i].addr);
+			ATF_CHECK_MSG(map_at_zero_tests[i].ok[map_at_zero] == 0,
+			    "mmap(%p, ...) failed", map_at_zero_tests[i].addr);
 		} else {
-			if (tests[i].ok[map_at_zero] != 1)
-				error++;
-			printf("%sok %d # mmap(%p, ...) succeeded: p=%p\n",
-			    tests[i].ok[map_at_zero] == 1 ? "" : "not ",
-			    i + 1,
-			    tests[i].addr, p);
+			ATF_CHECK_MSG(map_at_zero_tests[i].ok[map_at_zero] == 1,
+			    "mmap(%p, ...) succeeded: p=%p\n",
+			    map_at_zero_tests[i].addr, p);
 		}
 	}
+}
+
+ATF_TP_ADD_TCS(tp)
+{
+
+	ATF_TP_ADD_TC(tp, mmap__map_at_zero);
 
-	return (error != 0);
+	return (atf_no_error());
 }