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