diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 527d3bcfc69a..b1af9001e6db 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -1096,7 +1096,7 @@ static loff_t iomap_unshare_iter(struct iomap_iter *iter)
 		return length;
 
 	/*
-	 * Don't bother with holes or unwritten extents.
+	 * Don't bother with delalloc reservations, holes or unwritten extents.
 	 *
 	 * Note that we use srcmap directly instead of iomap_iter_srcmap as
 	 * unsharing requires providing a separate source map, and the presence
@@ -1105,6 +1105,7 @@ static loff_t iomap_unshare_iter(struct iomap_iter *iter)
 	 * fork for XFS.
 	 */
 	if (iter->srcmap.type == IOMAP_HOLE ||
+	    iter->srcmap.type == IOMAP_DELALLOC ||
 	    iter->srcmap.type == IOMAP_UNWRITTEN)
 		return length;