blob: 6583fe9b0645f6f4b5c417bc33ae5fea5bf99828 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * lowlevel.c
3 *
4 * PURPOSE
5 * Low Level Device Routines for the UDF filesystem
6 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 * 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 <asm/uaccess.h>
25
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include "udf_sb.h"
27
Cyrill Gorcunovcb00ea32007-07-19 01:47:43 -070028unsigned int udf_get_last_session(struct super_block *sb)
Linus Torvalds1da177e2005-04-16 15:20:36 -070029{
30 struct cdrom_multisession ms_info;
31 unsigned int vol_desc_start;
32 struct block_device *bdev = sb->s_bdev;
33 int i;
34
Cyrill Gorcunovcb00ea32007-07-19 01:47:43 -070035 vol_desc_start = 0;
36 ms_info.addr_format = CDROM_LBA;
37 i = ioctl_by_bdev(bdev, CDROMMULTISESSION, (unsigned long)&ms_info);
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
Cyrill Gorcunovcb00ea32007-07-19 01:47:43 -070039 if (i == 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070040 udf_debug("XA disk: %s, vol_desc_start=%d\n",
Joe Perchesa983f362011-10-10 01:08:07 -070041 ms_info.xa_flag ? "yes" : "no", ms_info.addr.lba);
Cyrill Gorcunov28de7942007-07-21 04:37:18 -070042 if (ms_info.xa_flag) /* necessary for a valid ms_info.addr */
Linus Torvalds1da177e2005-04-16 15:20:36 -070043 vol_desc_start = ms_info.addr.lba;
Cyrill Gorcunovcb00ea32007-07-19 01:47:43 -070044 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -070045 udf_debug("CDROMMULTISESSION not supported: rc=%d\n", i);
46 }
47 return vol_desc_start;
48}
49
Cyrill Gorcunovcb00ea32007-07-19 01:47:43 -070050unsigned long udf_get_last_block(struct super_block *sb)
Linus Torvalds1da177e2005-04-16 15:20:36 -070051{
52 struct block_device *bdev = sb->s_bdev;
53 unsigned long lblock = 0;
54
Jan Kara24a5d592009-06-18 12:33:16 +020055 /*
56 * ioctl failed or returned obviously bogus value?
57 * Try using the device size...
58 */
59 if (ioctl_by_bdev(bdev, CDROM_LAST_WRITTEN, (unsigned long) &lblock) ||
60 lblock == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -070061 lblock = bdev->bd_inode->i_size >> sb->s_blocksize_bits;
62
63 if (lblock)
64 return lblock - 1;
65 else
66 return 0;
67}