More fio.h cleanups

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/file.h b/file.h
index 2b49a6b..7024d5e 100644
--- a/file.h
+++ b/file.h
@@ -140,4 +140,12 @@
 extern int get_fileno(struct thread_data *, const char *);
 extern void free_release_files(struct thread_data *);
 
+static inline void fio_file_reset(struct fio_file *f)
+{
+	f->last_free_lookup = 0;
+	f->last_pos = f->file_offset;
+	if (f->file_map)
+		memset(f->file_map, 0, f->num_maps * sizeof(int));
+}
+
 #endif