diff --git a/fs/block_dev.c b/fs/block_dev.c
index 610e8e0..966617a 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -355,20 +355,25 @@
 	mutex_lock(&bd_inode->i_mutex);
 	size = i_size_read(bd_inode);
 
+	retval = -EINVAL;
 	switch (origin) {
-		case 2:
+		case SEEK_END:
 			offset += size;
 			break;
-		case 1:
+		case SEEK_CUR:
 			offset += file->f_pos;
+		case SEEK_SET:
+			break;
+		default:
+			goto out;
 	}
-	retval = -EINVAL;
 	if (offset >= 0 && offset <= size) {
 		if (offset != file->f_pos) {
 			file->f_pos = offset;
 		}
 		retval = offset;
 	}
+out:
 	mutex_unlock(&bd_inode->i_mutex);
 	return retval;
 }