ubi: Initialize Fastmap checkmapping correctly

commit 25677478 upstream

We cannot do it last, otherwithse it will be skipped for dynamic
volumes.
Reported-by: Lachmann, Juergen <juergen.lachmann@harman.com>
Fixes: 34653fd8 ("ubi: fastmap: Check each mapping only once")
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/mtd/ubi/vtbl.c

@@ -578,6 +578,16 @@ static int init_volumes(struct ubi_device *ubi,
 		vol->ubi = ubi;
 		reserved_pebs += vol->reserved_pebs;
 
+		/*
+		 * We use ubi->peb_count and not vol->reserved_pebs because
+		 * we want to keep the code simple. Otherwise we'd have to
+		 * resize/check the bitmap upon volume resize too.
+		 * Allocating a few bytes more does not hurt.
+		 */
+		err = ubi_fastmap_init_checkmap(vol, ubi->peb_count);
+		if (err)
+			return err;
+
 		/*
 		 * In case of dynamic volume UBI knows nothing about how many
 		 * data is stored there. So assume the whole volume is used.
@@ -620,16 +630,6 @@ static int init_volumes(struct ubi_device *ubi,
 			(long long)(vol->used_ebs - 1) * vol->usable_leb_size;
 		vol->used_bytes += av->last_data_size;
 		vol->last_eb_bytes = av->last_data_size;
-
-		/*
-		 * We use ubi->peb_count and not vol->reserved_pebs because
-		 * we want to keep the code simple. Otherwise we'd have to
-		 * resize/check the bitmap upon volume resize too.
-		 * Allocating a few bytes more does not hurt.
-		 */
-		err = ubi_fastmap_init_checkmap(vol, ubi->peb_count);
-		if (err)
-			return err;
 	}
 
 	/* And add the layout volume */