UBI: handle zero-length case
ubi_eba_atomic_leb_change() has to just map the LEB to a free PEB
if data length is zero.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c
index 1f7375e..7ce91ca 100644
--- a/drivers/mtd/ubi/eba.c
+++ b/drivers/mtd/ubi/eba.c
@@ -862,6 +862,17 @@
if (ubi->ro_mode)
return -EROFS;
+ if (len == 0) {
+ /*
+ * Special case when data length is zero. In this case the LEB
+ * has to be unmapped and mapped somewhere else.
+ */
+ err = ubi_eba_unmap_leb(ubi, vol, lnum);
+ if (err)
+ return err;
+ return ubi_eba_write_leb(ubi, vol, lnum, NULL, 0, 0, dtype);
+ }
+
vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);
if (!vid_hdr)
return -ENOMEM;