test/zdtm/static/maps02: add MAP_DROPPABLE testcase

Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>

Author: mihalicyn

test/zdtm/static/get_smaps_bits.c

@@ -6,6 +6,10 @@
 #define MAP_HUGETLB 0x40000
 #endif
 
+#ifndef MAP_DROPPABLE
+#define MAP_DROPPABLE 0x08
+#endif
+
 #ifndef MADV_HUGEPAGE
 #define MADV_HUGEPAGE 14
 #endif
@@ -45,6 +49,8 @@ static void parse_vmflags(char *buf, unsigned long *flags, unsigned long *madv)
 			*flags |= MAP_NORESERVE;
 		else if (_vmflag_match(tok, "ht"))
 			*flags |= MAP_HUGETLB;
+		else if (_vmflag_match(tok, "dp"))
+			*flags |= MAP_DROPPABLE;
 
 		/* madvise() block */
 		if (_vmflag_match(tok, "sr"))

test/zdtm/static/maps02.c

@@ -2,6 +2,10 @@
 #include "zdtmtst.h"
 #include "get_smaps_bits.h"
 
+#ifndef MAP_DROPPABLE
+#define MAP_DROPPABLE 0x08
+#endif
+
 #ifndef MADV_DONTDUMP
 #define MADV_DONTDUMP 16
 #endif
@@ -27,8 +31,14 @@ static int alloc_anon_mmap(struct mmap_data *m, int flags, int adv)
 {
 	m->start = mmap(NULL, MEM_SIZE, PROT_READ | PROT_WRITE, flags, -1, 0);
 	if (m->start == MAP_FAILED) {
-		pr_perror("mmap failed");
-		return -1;
+		if (errno == EINVAL) {
+			test_msg("mmap failed, no kernel support\n");
+			*m = (struct mmap_data){};
+			return 0;
+		} else {
+			pr_perror("mmap failed");
+			return -1;
+		}
 	}
 
 	if (madvise(m->start, MEM_SIZE, adv)) {
@@ -47,7 +57,7 @@ static int alloc_anon_mmap(struct mmap_data *m, int flags, int adv)
 
 int main(int argc, char **argv)
 {
-	struct mmap_data m[6] = {};
+	struct mmap_data m[7] = {};
 	size_t i;
 
 	test_init(argc, argv);
@@ -76,6 +86,10 @@ int main(int argc, char **argv)
 	if (alloc_anon_mmap(&m[5], MAP_PRIVATE | MAP_ANONYMOUS, MADV_WIPEONFORK))
 		return -1;
 
+	test_msg("Alloc droppable\n");
+	if (alloc_anon_mmap(&m[6], MAP_DROPPABLE | MAP_ANONYMOUS, MADV_NORMAL))
+		return -1;
+
 	test_msg("Fetch existing flags/adv\n");
 	for (i = 0; i < sizeof(m) / sizeof(m[0]); i++) {
 		if (get_smaps_bits((unsigned long)m[i].start, &m[i].orig_flags, &m[i].orig_madv))