// SPDX-License-Identifier: GPL-2.0-only/* * lowlevel.c * * PURPOSE *  Low Level Device Routines for the UDF filesystem * * COPYRIGHT *  (C) 1999-2001 Ben Fennema * * HISTORY * *  03/26/99 blf  Created. */ #include "udfdecl.h" #include <linux/blkdev.h>#include <linux/cdrom.h>#include <linux/uaccess.h> #include "udf_sb.h" unsigned int udf_get_last_session(struct super_block *sb){	struct cdrom_device_info *cdi = disk_to_cdi(sb->s_bdev->bd_disk);	struct cdrom_multisession ms_info; 	if (!cdi) {		udf_debug("CDROMMULTISESSION not supported.\n");		return 0;	} 	ms_info.addr_format = CDROM_LBA;	if (cdrom_multisession(cdi, &ms_info) == 0) {		udf_debug("XA disk: %s, vol_desc_start=%d\n",			  ms_info.xa_flag ? "yes" : "no", ms_info.addr.lba);		if (ms_info.xa_flag) /* necessary for a valid ms_info.addr */			return ms_info.addr.lba;	}	return 0;} udf_pblk_t udf_get_last_block(struct super_block *sb){	struct cdrom_device_info *cdi = disk_to_cdi(sb->s_bdev->bd_disk);	unsigned long lblock = 0; 	/*	 * The cdrom layer call failed or returned obviously bogus value?	 * Try using the device size...	 */	if (!cdi || cdrom_get_last_written(cdi, &lblock) || lblock == 0) {		if (sb_bdev_nr_blocks(sb) > ~(udf_pblk_t)0)			return 0;		lblock = sb_bdev_nr_blocks(sb);	} 	if (lblock)		return lblock - 1;	return 0;}