1 files changed, 22 insertions, 0 deletions
diff --git a/mm/internal.h b/mm/internal.h
index d5b93c5b6364..5a7302baeed7 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -1291,6 +1291,28 @@ static inline bool alloc_zeroed(void)
 			&init_on_alloc);
 }
 
+/*
+ * Parses a string with mem suffixes into its order. Useful to parse kernel
+ * parameters.
+ */
+static inline int get_order_from_str(const char *size_str,
+				     unsigned long valid_orders)
+{
+	unsigned long size;
+	char *endptr;
+	int order;
+
+	size = memparse(size_str, &endptr);
+
+	if (!is_power_of_2(size))
+		return -EINVAL;
+	order = get_order(size);
+	if (BIT(order) & ~valid_orders)
+		return -EINVAL;
+
+	return order;
+}
+
 enum {
 	/* mark page accessed */
 	FOLL_TOUCH = 1 << 16,