[PATCH] md/bitmap: fix online removal of file-backed bitmaps

When "mdadm --grow /dev/mdX --bitmap=none" is used to remove a filebacked
bitmap, the bitmap was disconnected from the array, but the file wasn't closed
(until the array was stopped).

The file also wasn't closed if adding the bitmap file failed.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

drivers/md/md.c

@@ -3601,10 +3601,13 @@ static int set_bitmap_file(mddev_t *mddev, int fd)
 		mddev->pers->quiesce(mddev, 1);
 		if (fd >= 0)
 			err = bitmap_create(mddev);
-		if (fd < 0 || err)
+		if (fd < 0 || err) {
 			bitmap_destroy(mddev);
+			fd = -1; /* make sure to put the file */
+		}
 		mddev->pers->quiesce(mddev, 0);
-	} else if (fd < 0) {
+	}
+	if (fd < 0) {
 		if (mddev->bitmap_file)
 			fput(mddev->bitmap_file);
 		mddev->bitmap_file = NULL;