cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

lowlevel.c (1485B)

      1/*
      2 * lowlevel.c
      3 *
      4 * PURPOSE
      5 *  Low Level Device Routines for the UDF filesystem
      6 *
      7 * COPYRIGHT
      8 *	This file is distributed under the terms of the GNU General Public
      9 *	License (GPL). Copies of the GPL can be obtained from:
     10 *		ftp://prep.ai.mit.edu/pub/gnu/GPL
     11 *	Each contributing author retains all rights to their own work.
     12 *
     13 *  (C) 1999-2001 Ben Fennema
     14 *
     15 * HISTORY
     16 *
     17 *  03/26/99 blf  Created.
     18 */
     19
     20#include "udfdecl.h"
     21
     22#include <linux/blkdev.h>
     23#include <linux/cdrom.h>
     24#include <linux/uaccess.h>
     25
     26#include "udf_sb.h"
     27
     28unsigned int udf_get_last_session(struct super_block *sb)
     29{
     30	struct cdrom_device_info *cdi = disk_to_cdi(sb->s_bdev->bd_disk);
     31	struct cdrom_multisession ms_info;
     32
     33	if (!cdi) {
     34		udf_debug("CDROMMULTISESSION not supported.\n");
     35		return 0;
     36	}
     37
     38	ms_info.addr_format = CDROM_LBA;
     39	if (cdrom_multisession(cdi, &ms_info) == 0) {
     40		udf_debug("XA disk: %s, vol_desc_start=%d\n",
     41			  ms_info.xa_flag ? "yes" : "no", ms_info.addr.lba);
     42		if (ms_info.xa_flag) /* necessary for a valid ms_info.addr */
     43			return ms_info.addr.lba;
     44	}
     45	return 0;
     46}
     47
     48unsigned long udf_get_last_block(struct super_block *sb)
     49{
     50	struct cdrom_device_info *cdi = disk_to_cdi(sb->s_bdev->bd_disk);
     51	unsigned long lblock = 0;
     52
     53	/*
     54	 * The cdrom layer call failed or returned obviously bogus value?
     55	 * Try using the device size...
     56	 */
     57	if (!cdi || cdrom_get_last_written(cdi, &lblock) || lblock == 0)
     58		lblock = sb_bdev_nr_blocks(sb);
     59
     60	if (lblock)
     61		return lblock - 1;
     62	return 0;
     63}