UBI: Add accessor functions for WL data structures

Fastmap need access to various WL data structures as
fastmap tightly depends on WL.
To make the access less invasive add accessor functions.
Signed-off-by: NRichard Weinberger <richard@nod.at>

drivers/mtd/ubi/ubi.h

@@ -904,6 +904,42 @@ static inline int ubiblock_remove(struct ubi_volume_info *vi)
 }
 #endif
 
+/*
+ * ubi_for_each_free_peb - walk the UBI free RB tree.
+ * @ubi: UBI device description object
+ * @e: a pointer to a ubi_wl_entry to use as cursor
+ * @pos: a pointer to RB-tree entry type to use as a loop counter
+ */
+#define ubi_for_each_free_peb(ubi, e, tmp_rb)	\
+	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->free, u.rb)
+
+/*
+ * ubi_for_each_used_peb - walk the UBI used RB tree.
+ * @ubi: UBI device description object
+ * @e: a pointer to a ubi_wl_entry to use as cursor
+ * @pos: a pointer to RB-tree entry type to use as a loop counter
+ */
+#define ubi_for_each_used_peb(ubi, e, tmp_rb)	\
+	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->used, u.rb)
+
+/*
+ * ubi_for_each_scub_peb - walk the UBI scub RB tree.
+ * @ubi: UBI device description object
+ * @e: a pointer to a ubi_wl_entry to use as cursor
+ * @pos: a pointer to RB-tree entry type to use as a loop counter
+ */
+#define ubi_for_each_scrub_peb(ubi, e, tmp_rb)	\
+	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->scrub, u.rb)
+
+/*
+ * ubi_for_each_protected_peb - walk the UBI protection queue.
+ * @ubi: UBI device description object
+ * @i: a integer used as counter
+ * @e: a pointer to a ubi_wl_entry to use as cursor
+ */
+#define ubi_for_each_protected_peb(ubi, i, e)	\
+	for ((i) = 0; (i) < UBI_PROT_QUEUE_LEN; (i)++)	\
+		list_for_each_entry((e), &(ubi->pq[(i)]), u.list)
 
 /*
  * ubi_rb_for_each_entry - walk an RB-tree.