+/**
+ * Size of the header once saved on disk.
+ * \see battfs_to_disk
+ * \see disk_to_battfs
+ */
+#define BATTFS_HEADER_LEN 13
+
+/**
+ * Marks for valid pages.
+ * Simply set to 1 all field bits.
+ * \{
+ */
+#define MARK_PAGE_VALID ((1LL << (CPU_BITS_PER_CHAR * sizeof(mark_t))) - 1)
+#define FCS_FREE_VALID ((1 << (CPU_BITS_PER_CHAR * sizeof(fcs_t))) - 1)
+/* \} */
+
+
+/**
+ * Half-size of free page marker.
+ * Used to keep trace of free marker wrap-arounds.
+ */
+#define MARK_HALF_SIZE (1 << (CPU_BITS_PER_CHAR * sizeof(pgaddr_t) + 1))
+
+/**
+ * Maximum page address.
+ */
+#define MAX_PAGE_ADDR ((1 << (CPU_BITS_PER_CHAR * sizeof(pgaddr_t))) - 1)
+
+/**
+ * Max number of files.
+ */
+#define BATTFS_MAX_FILES (1 << (CPU_BITS_PER_CHAR * sizeof(inode_t)))