xpmem: support large page

1. try to use as large page as possible on attach
2. pre-map resident remote pages on attach

Change-Id: I5580682a4199e94085a9bad9ce3958a0f14cdcea

test/issues/1259/util2.h

@@ -0,0 +1,31 @@
+#define CHKANDJUMP(cond, ...)	do {		\
+	if (cond) {				\
+		fprintf(stderr, " [NG] ");	\
+		fprintf(stderr, __VA_ARGS__);	\
+		fprintf(stderr, " failed\n");	\
+		goto fn_fail;			\
+	}					\
+} while (0)
+
+#define OKNG(cond, ...)		do {		\
+	if (cond) {				\
+		CHKANDJUMP(cond, __VA_ARGS__);	\
+	} else {				\
+		fprintf(stdout, " [OK] ");	\
+		fprintf(stdout, __VA_ARGS__);	\
+		fprintf(stdout, "\n");		\
+	}					\
+} while (0)
+
+
+#ifdef __aarch64__
+#define LARGE_PAGE_SHIFT 21
+#elif defined(__x86_64__)
+#define LARGE_PAGE_SHIFT 21
+#else
+#error "Non-compliant architecture."
+#endif
+
+#define MAP_HUGE_SHIFT 26
+#define SZ_MEM (2 * (1ULL << LARGE_PAGE_SHIFT))
+#define TEST_VAL 0x1129