DATAHD
case DATAHD:
err = make_reservation(c, DATAHD, write_len);
err = write_head(c, DATAHD, data, write_len, &lnum, &offs, 0);
ubifs_wbuf_add_ino_nolock(&c->jheads[DATAHD].wbuf, key_inum(c, key));
release_head(c, DATAHD);
release_head(c, DATAHD);