// 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;
}