aboutsummaryrefslogblamecommitdiffstats
path: root/fs/udf/super.c
blob: 4df822c881b69357038f96f0d91f6231f7da4a15 (plain) (tree)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313















                                                                      

























                                                                                       

















































                                                                                             
                                                         

                         

                                                                          
 
                                                                                









































                                                                                      

                                                                      































































































































                                                                                     
                                                                   











                                     



                                    



































































































































                                                                              











                                                                          





































































































































































































































                                                                                                      
                                                                      









                                                                                         
 















































































                                                                                                                                           
                                                             













































































































































































































































































































































































































































































































































































                                                                                                                                
                                                             









                                                                                      
 

















                                                                                          
                                                 

                                                     
              




































































































































































                                                                                                                                                              
                                        










































































































































































































































































                                                                                                          
                                                      
 

                                              





























































































































































                                                                                                   
/*
 * super.c
 *
 * PURPOSE
 *  Super block routines for the OSTA-UDF(tm) filesystem.
 *
 * DESCRIPTION
 *  OSTA-UDF(tm) = Optical Storage Technology Association
 *  Universal Disk Format.
 *
 *  This code is based on version 2.00 of the UDF specification,
 *  and revision 3 of the ECMA 167 standard [equivalent to ISO 13346].
 *    http://www.osta.org/
 *    http://www.ecma.ch/
 *    http://www.iso.org/
 *
 * COPYRIGHT
 *  This file is distributed under the terms of the GNU General Public
 *  License (GPL). Copies of the GPL can be obtained from:
 *    ftp://prep.ai.mit.edu/pub/gnu/GPL
 *  Each contributing author retains all rights to their own work.
 *
 *  (C) 1998 Dave Boynton
 *  (C) 1998-2004 Ben Fennema
 *  (C) 2000 Stelias Computing Inc
 *
 * HISTORY
 *
 *  09/24/98 dgb  changed to allow compiling outside of kernel, and
 *                added some debugging.
 *  10/01/98 dgb  updated to allow (some) possibility of compiling w/2.0.34
 *  10/16/98      attempting some multi-session support
 *  10/17/98      added freespace count for "df"
 *  11/11/98 gr   added novrs option
 *  11/26/98 dgb  added fileset,anchor mount options
 *  12/06/98 blf  really hosed things royally. vat/sparing support. sequenced vol descs
 *                rewrote option handling based on isofs
 *  12/20/98      find the free space bitmap (if it exists)
 */

#include "udfdecl.h"    

#include <linux/blkdev.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/parser.h>
#include <linux/stat.h>
#include <linux/cdrom.h>
#include <linux/nls.h>
#include <linux/smp_lock.h>
#include <linux/buffer_head.h>
#include <linux/vfs.h>
#include <linux/vmalloc.h>
#include <asm/byteorder.h>

#include <linux/udf_fs.h>
#include "udf_sb.h"
#include "udf_i.h"

#include <linux/init.h>
#include <asm/uaccess.h>

#define VDS_POS_PRIMARY_VOL_DESC	0
#define VDS_POS_UNALLOC_SPACE_DESC	1
#define VDS_POS_LOGICAL_VOL_DESC	2
#define VDS_POS_PARTITION_DESC		3
#define VDS_POS_IMP_USE_VOL_DESC	4
#define VDS_POS_VOL_DESC_PTR		5
#define VDS_POS_TERMINATING_DESC	6
#define VDS_POS_LENGTH			7

static char error_buf[1024];

/* These are the "meat" - everything else is stuffing */
static int udf_fill_super(struct super_block *, void *, int);
static void udf_put_super(struct super_block *);
static void udf_write_super(struct super_block *);
static int udf_remount_fs(struct super_block *, int *, char *);
static int udf_check_valid(struct super_block *, int, int);
static int udf_vrs(struct super_block *sb, int silent);
static int udf_load_partition(struct super_block *, kernel_lb_addr *);
static int udf_load_logicalvol(struct super_block *, struct buffer_head *, kernel_lb_addr *);
static void udf_load_logicalvolint(struct super_block *, kernel_extent_ad);
static void udf_find_anchor(struct super_block *);
static int udf_find_fileset(struct super_block *, kernel_lb_addr *, kernel_lb_addr *);
static void udf_load_pvoldesc(struct super_block *, struct buffer_head *);
static void udf_load_fileset(struct super_block *, struct buffer_head *, kernel_lb_addr *);
static void udf_load_partdesc(struct super_block *, struct buffer_head *);
static void udf_open_lvid(struct super_block *);
static void udf_close_lvid(struct super_block *);
static unsigned int udf_count_free(struct super_block *);
static int udf_statfs(struct dentry *, struct kstatfs *);

/* UDF filesystem type */
static int udf_get_sb(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *data, struct vfsmount *mnt)
{
	return get_sb_bdev(fs_type, flags, dev_name, data, udf_fill_super, mnt);
}

static struct file_system_type udf_fstype = {
	.owner		= THIS_MODULE,
	.name		= "udf",
	.get_sb		= udf_get_sb,
	.kill_sb	= kill_block_super,
	.fs_flags	= FS_REQUIRES_DEV,
};

static kmem_cache_t * udf_inode_cachep;

static struct inode *udf_alloc_inode(struct super_block *sb)
{
	struct udf_inode_info *ei;
	ei = (struct udf_inode_info *)kmem_cache_alloc(udf_inode_cachep, SLAB_KERNEL);
	if (!ei)
		return NULL;
	return &ei->vfs_inode;
}

static void udf_destroy_inode(struct inode *inode)
{
	kmem_cache_free(udf_inode_cachep, UDF_I(inode));
}

static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
{
	struct udf_inode_info *ei = (struct udf_inode_info *) foo;

	if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
	    SLAB_CTOR_CONSTRUCTOR)
	{
		ei->i_ext.i_data = NULL;
		inode_init_once(&ei->vfs_inode);
	}
}

static int init_inodecache(void)
{
	udf_inode_cachep = kmem_cache_create("udf_inode_cache",
					     sizeof(struct udf_inode_info),
					     0, (SLAB_RECLAIM_ACCOUNT|
						SLAB_MEM_SPREAD),
					     init_once, NULL);
	if (udf_inode_cachep == NULL)
		return -ENOMEM;
	return 0;
}

static void destroy_inodecache(void)
{
	if (kmem_cache_destroy(udf_inode_cachep))
		printk(KERN_INFO "udf_inode_cache: not all structures were freed\n");
}

/* Superblock operations */
static struct super_operations udf_sb_ops = {
	.alloc_inode		= udf_alloc_inode,
	.destroy_inode		= udf_destroy_inode,
	.write_inode		= udf_write_inode,
	.delete_inode		= udf_delete_inode,
	.clear_inode		= udf_clear_inode,
	.put_super		= udf_put_super,
	.write_super		= udf_write_super,
	.statfs			= udf_statfs,
	.remount_fs		= udf_remount_fs,
};

struct udf_options
{
	unsigned char novrs;
	unsigned int blocksize;
	unsigned int session;
	unsigned int lastblock;
	unsigned int anchor;
	unsigned int volume;
	unsigned short partition;
	unsigned int fileset;
	unsigned int rootdir;
	unsigned int flags;
	mode_t umask;
	gid_t gid;
	uid_t uid;
	struct nls_table *nls_map;
};

static int __init init_udf_fs(void)
{
	int err;
	err = init_inodecache();
	if (err)
		goto out1;
	err = register_filesystem(&udf_fstype);
	if (err)
		goto out;
	return 0;
out:
	destroy_inodecache();
out1:
	return err;
}

static void __exit exit_udf_fs(void)
{
	unregister_filesystem(&udf_fstype);
	destroy_inodecache();
}

module_init(init_udf_fs)
module_exit(exit_udf_fs)

/*
 * udf_parse_options
 *
 * PURPOSE
 *	Parse mount options.
 *
 * DESCRIPTION
 *	The following mount options are supported:
 *
 *	gid=		Set the default group.
 *	umask=		Set the default umask.
 *	uid=		Set the default user.
 *	bs=		Set the block size.
 *	unhide		Show otherwise hidden files.
 *	undelete	Show deleted files in lists.
 *	adinicb		Embed data in the inode (default)
 *	noadinicb	Don't embed data in the inode
 *	shortad		Use short ad's
 *	longad		Use long ad's (default)
 *	nostrict	Unset strict conformance
 *	iocharset=	Set the NLS character set
 *
 *	The remaining are for debugging and disaster recovery:
 *
 *	novrs		Skip volume sequence recognition 
 *
 *	The following expect a offset from 0.
 *
 *	session=	Set the CDROM session (default= last session)
 *	anchor=		Override standard anchor location. (default= 256)
 *	volume=		Override the VolumeDesc location. (unused)
 *	partition=	Override the PartitionDesc location. (unused)
 *	lastblock=	Set the last block of the filesystem/
 *
 *	The following expect a offset from the partition root.
 *
 *	fileset=	Override the fileset block location. (unused)
 *	rootdir=	Override the root directory location. (unused)
 *		WARNING: overriding the rootdir to a non-directory may
 *		yield highly unpredictable results.
 *
 * PRE-CONDITIONS
 *	options		Pointer to mount options string.
 *	uopts		Pointer to mount options variable.
 *
 * POST-CONDITIONS
 *	<return>	1	Mount options parsed okay.
 *	<return>	0	Error parsing mount options.
 *
 * HISTORY
 *	July 1, 1997 - Andrew E. Mileski
 *	Written, tested, and released.
 */

enum {
	Opt_novrs, Opt_nostrict, Opt_bs, Opt_unhide, Opt_undelete,
	Opt_noadinicb, Opt_adinicb, Opt_shortad, Opt_longad,
	Opt_gid, Opt_uid, Opt_umask, Opt_session, Opt_lastblock,
	Opt_anchor, Opt_volume, Opt_partition, Opt_fileset,
	Opt_rootdir, Opt_utf8, Opt_iocharset,
	Opt_err, Opt_uforget, Opt_uignore, Opt_gforget, Opt_gignore
};

static match_table_t tokens = {
	{Opt_novrs, "novrs"},
	{Opt_nostrict, "nostrict"},
	{Opt_bs, "bs=%u"},
	{Opt_unhide, "unhide"},
	{Opt_undelete, "undelete"},
	{Opt_noadinicb, "noadinicb"},
	{Opt_adinicb, "adinicb"},
	{Opt_shortad, "shortad"},
	{Opt_longad, "longad"},
	{Opt_uforget, "uid=forget"},
	{Opt_uignore, "uid=ignore"},
	{Opt_gforget, "gid=forget"},
	{Opt_gignore, "gid=ignore"},
	{Opt_gid, "gid=%u"},
	{Opt_uid, "uid=%u"},
	{Opt_umask, "umask=%o"},
	{Opt_session, "session=%u"},
	{Opt_lastblock, "lastblock=%u"},
	{Opt_anchor, "anchor=%u"},
	{Opt_volume, "volume=%u"},
	{Opt_partition, "partition=%u"},
	{Opt_fileset, "fileset=%u"},
	{Opt_rootdir, "rootdir=%u"},
	{Opt_utf8, "utf8"},
	{Opt_iocharset, "iocharset=%s"},
	{Opt_err, NULL}
};

static int
udf_parse_options(char *options, struct udf_options *uopt)
{
	char *p;
	int option;

	uopt->novrs = 0;
	uopt->blocksize = 2048;
	uopt->partition = 0xFFFF;
	uopt->session = 0xFFFFFFFF;
	uopt->lastblock = 0;
	uopt->anchor = 0;
	uopt->volume = 0xFFFFFFFF;
	uopt->rootdir = 0xFFFFFFFF;
	uopt->fileset = 0xFFFFFFFF;
	uopt->nls_map = NULL;

	if (!options)
		return 1;

	while ((p = strsep(&options, ",")) != NULL)
	{
		substring_t args[MAX_OPT_ARGS];
		int token;
		if (!*p)
			continue;

		token = match_token(p, tokens, args);
		switch (token)
		{
			case Opt_novrs:
				uopt->novrs = 1;
			case Opt_bs:
				if (match_int(&args[0], &option))
					return 0;
				uopt->blocksize = option;
				break;
			case Opt_unhide:
				uopt->flags |= (1 << UDF_FLAG_UNHIDE);
				break;
			case Opt_undelete:
				uopt->flags |= (1 << UDF_FLAG_UNDELETE);
				break;
			case Opt_noadinicb:
				uopt->flags &= ~(1 << UDF_FLAG_USE_AD_IN_ICB);
				break;
			case Opt_adinicb:
				uopt->flags |= (1 << UDF_FLAG_USE_AD_IN_ICB);
				break;
			case Opt_shortad:
				uopt->flags |= (1 << UDF_FLAG_USE_SHORT_AD);
				break;
			case Opt_longad:
				uopt->flags &= ~(1 << UDF_FLAG_USE_SHORT_AD);
				break;
			case Opt_gid:
				if (match_int(args, &option))
					return 0;
				uopt->gid = option;
				break;
			case Opt_uid:
				if (match_int(args, &option))
					return 0;
				uopt->uid = option;
				break;
			case Opt_umask:
				if (match_octal(args, &option))
					return 0;
				uopt->umask = option;
				break;
			case Opt_nostrict:
				uopt->flags &= ~(1 << UDF_FLAG_STRICT);
				break;
			case Opt_session:
				if (match_int(args, &option))
					return 0;
				uopt->session = option;
				break;
			case Opt_lastblock:
				if (match_int(args, &option))
					return 0;
				uopt->lastblock = option;
				break;
			case Opt_anchor:
				if (match_int(args, &option))
					return 0;
				uopt->anchor = option;
				break;
			case Opt_volume:
				if (match_int(args, &option))
					return 0;
				uopt->volume = option;
				break;
			case Opt_partition:
				if (match_int(args, &option))
					return 0;
				uopt->partition = option;
				break;
			case Opt_fileset:
				if (match_int(args, &option))
					return 0;
				uopt->fileset = option;
				break;
			case Opt_rootdir:
				if (match_int(args, &option))
					return 0;
				uopt->rootdir = option;
				break;
			case Opt_utf8:
				uopt->flags |= (1 << UDF_FLAG_UTF8);
				break;
#ifdef CONFIG_UDF_NLS
			case Opt_iocharset:
				uopt->nls_map = load_nls(args[0].from);
				uopt->flags |= (1 << UDF_FLAG_NLS_MAP);
				break;
#endif
			case Opt_uignore:
				uopt->flags |= (1 << UDF_FLAG_UID_IGNORE);
				break;
			case Opt_uforget:
				uopt->flags |= (1 << UDF_FLAG_UID_FORGET);
				break;
			case Opt_gignore:
			    uopt->flags |= (1 << UDF_FLAG_GID_IGNORE);
				break;
			case Opt_gforget:
			    uopt->flags |= (1 << UDF_FLAG_GID_FORGET);
				break;
			default:
				printk(KERN_ERR "udf: bad mount option \"%s\" "
						"or missing value\n", p);
			return 0;
		}
	}
	return 1;
}

void
udf_write_super(struct super_block *sb)
{
	lock_kernel();
	if (!(sb->s_flags & MS_RDONLY))
		udf_open_lvid(sb);
	sb->s_dirt = 0;
	unlock_kernel();
}

static int
udf_remount_fs(struct super_block *sb, int *flags, char *options)
{
	struct udf_options uopt;

	uopt.flags = UDF_SB(sb)->s_flags ;
	uopt.uid   = UDF_SB(sb)->s_uid ;
	uopt.gid   = UDF_SB(sb)->s_gid ;
	uopt.umask = UDF_SB(sb)->s_umask ;

	if ( !udf_parse_options(options, &uopt) )
		return -EINVAL;

	UDF_SB(sb)->s_flags = uopt.flags;
	UDF_SB(sb)->s_uid   = uopt.uid;
	UDF_SB(sb)->s_gid   = uopt.gid;
	UDF_SB(sb)->s_umask = uopt.umask;

	if (UDF_SB_LVIDBH(sb)) {
		int write_rev = le16_to_cpu(UDF_SB_LVIDIU(sb)->minUDFWriteRev);
		if (write_rev > UDF_MAX_WRITE_VERSION)
			*flags |= MS_RDONLY;
	}

	if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
		return 0;
	if (*flags & MS_RDONLY)
		udf_close_lvid(sb);
	else
		udf_open_lvid(sb);

	return 0;
}

/*
 * udf_set_blocksize
 *
 * PURPOSE
 *	Set the block size to be used in all transfers.
 *
 * DESCRIPTION
 *	To allow room for a DMA transfer, it is best to guess big when unsure.
 *	This routine picks 2048 bytes as the blocksize when guessing. This
 *	should be adequate until devices with larger block sizes become common.
 *
 *	Note that the Linux kernel can currently only deal with blocksizes of
 *	512, 1024, 2048, 4096, and 8192 bytes.
 *
 * PRE-CONDITIONS
 *	sb			Pointer to _locked_ superblock.
 *
 * POST-CONDITIONS
 *	sb->s_blocksize		Blocksize.
 *	sb->s_blocksize_bits	log2 of blocksize.
 *	<return>	0	Blocksize is valid.
 *	<return>	1	Blocksize is invalid.
 *
 * HISTORY
 *	July 1, 1997 - Andrew E. Mileski
 *	Written, tested, and released.
 */
static  int
udf_set_blocksize(struct super_block *sb, int bsize)
{
	if (!sb_min_blocksize(sb, bsize)) {
		udf_debug("Bad block size (%d)\n", bsize);
		printk(KERN_ERR "udf: bad block size (%d)\n", bsize);
		return 0;
	}
	return sb->s_blocksize;
}

static int
udf_vrs(struct super_block *sb, int silent)
{
	struct volStructDesc *vsd = NULL;
	int sector = 32768;
	int sectorsize;
	struct buffer_head *bh = NULL;
	int iso9660=0;
	int nsr02=0;
	int nsr03=0;

	/* Block size must be a multiple of 512 */
	if (sb->s_blocksize & 511)
		return 0;

	if (sb->s_blocksize < sizeof(struct volStructDesc))
		sectorsize = sizeof(struct volStructDesc);
	else
		sectorsize = sb->s_blocksize;

	sector += (UDF_SB_SESSION(sb) << sb->s_blocksize_bits);

	udf_debug("Starting at sector %u (%ld byte sectors)\n",
		(sector >> sb->s_blocksize_bits), sb->s_blocksize);
	/* Process the sequence (if applicable) */
	for (;!nsr02 && !nsr03; sector += sectorsize)
	{
		/* Read a block */
		bh = udf_tread(sb, sector >> sb->s_blocksize_bits);
		if (!bh)
			break;

		/* Look for ISO  descriptors */
		vsd = (struct volStructDesc *)(bh->b_data +
			(sector & (sb->s_blocksize - 1)));

		if (vsd->stdIdent[0] == 0)
		{
			udf_release_data(bh);
			break;
		}
		else if (!strncmp(vsd->stdIdent, VSD_STD_ID_CD001, VSD_STD_ID_LEN))
		{
			iso9660 = sector;
			switch (vsd->structType)
			{
				case 0: 
					udf_debug("ISO9660 Boot Record found\n");
					break;
				case 1: 
					udf_debug("ISO9660 Primary Volume Descriptor found\n");
					break;
				case 2: 
					udf_debug("ISO9660 Supplementary Volume Descriptor found\n");
					break;
				case 3: 
					udf_debug("ISO9660 Volume Partition Descriptor found\n");
					break;
				case 255: 
					udf_debug("ISO9660 Volume Descriptor Set Terminator found\n");
					break;
				default: 
					udf_debug("ISO9660 VRS (%u) found\n", vsd->structType);
					break;
			}
		}
		else if (!strncmp(vsd->stdIdent, VSD_STD_ID_BEA01, VSD_STD_ID_LEN))
		{
		}
		else if (!strncmp(vsd->stdIdent, VSD_STD_ID_TEA01, VSD_STD_ID_LEN))
		{
			udf_release_data(bh);
			break;
		}
		else if (!strncmp(vsd->stdIdent, VSD_STD_ID_NSR02, VSD_STD_ID_LEN))
		{
			nsr02 = sector;
		}
		else if (!strncmp(vsd->stdIdent, VSD_STD_ID_NSR03, VSD_STD_ID_LEN))
		{
			nsr03 = sector;
		}
		udf_release_data(bh);
	}

	if (nsr03)
		return nsr03;
	else if (nsr02)
		return nsr02;
	else if (sector - (UDF_SB_SESSION(sb) << sb->s_blocksize_bits) == 32768)
		return -1;
	else
		return 0;
}

/*
 * udf_find_anchor
 *
 * PURPOSE
 *	Find an anchor volume descriptor.
 *
 * PRE-CONDITIONS
 *	sb			Pointer to _locked_ superblock.
 *	lastblock		Last block on media.
 *
 * POST-CONDITIONS
 *	<return>		1 if not found, 0 if ok
 *
 * HISTORY
 *	July 1, 1997 - Andrew E. Mileski
 *	Written, tested, and released.
 */
static void
udf_find_anchor(struct super_block *sb)
{
	int lastblock = UDF_SB_LASTBLOCK(sb);
	struct buffer_head *bh = NULL;
	uint16_t ident;
	uint32_t location;
	int i;

	if (lastblock)
	{
		int varlastblock = udf_variable_to_fixed(lastblock);
		int last[] =  { lastblock, lastblock - 2,
				lastblock - 150, lastblock - 152,
				varlastblock, varlastblock - 2,
				varlastblock - 150, varlastblock - 152 };

		lastblock = 0;

		/* Search for an anchor volume descriptor pointer */

		/*  according to spec, anchor is in either:
		 *     block 256
		 *     lastblock-256
		 *     lastblock
		 *  however, if the disc isn't closed, it could be 512 */

		for (i = 0; !lastblock && i < ARRAY_SIZE(last); i++) {
			if (last[i] < 0 || !(bh = sb_bread(sb, last[i])))
			{
				ident = location = 0;
			}
			else
			{
				ident = le16_to_cpu(((tag *)bh->b_data)->tagIdent);
				location = le32_to_cpu(((tag *)bh->b_data)->tagLocation);
				udf_release_data(bh);
			}

			if (ident == TAG_IDENT_AVDP)
			{
				if (location == last[i] - UDF_SB_SESSION(sb))
				{
					lastblock = UDF_SB_ANCHOR(sb)[0] = last[i] - UDF_SB_SESSION(sb);
					UDF_SB_ANCHOR(sb)[1] = last[i] - 256 - UDF_SB_SESSION(sb);
				}
				else if (location == udf_variable_to_fixed(last[i]) - UDF_SB_SESSION(sb))
				{
					UDF_SET_FLAG(sb, UDF_FLAG_VARCONV);
					lastblock = UDF_SB_ANCHOR(sb)[0] = udf_variable_to_fixed(last[i]) - UDF_SB_SESSION(sb);
					UDF_SB_ANCHOR(sb)[1] = lastblock - 256 - UDF_SB_SESSION(sb);
				}
				else
					udf_debug("Anchor found at block %d, location mismatch %d.\n",
						last[i], location);
			}
			else if (ident == TAG_IDENT_FE || ident == TAG_IDENT_EFE)
			{
				lastblock = last[i];
				UDF_SB_ANCHOR(sb)[3] = 512;
			}
			else
			{
				if (last[i] < 256 || !(bh = sb_bread(sb, last[i] - 256)))
				{
					ident = location = 0;
				}
				else
				{
					ident = le16_to_cpu(((tag *)bh->b_data)->tagIdent);
					location = le32_to_cpu(((tag *)bh->b_data)->tagLocation);
					udf_release_data(bh);
				}
	
				if (ident == TAG_IDENT_AVDP &&
					location == last[i] - 256 - UDF_SB_SESSION(sb))
				{
					lastblock = last[i];
					UDF_SB_ANCHOR(sb)[1] = last[i] - 256;
				}
				else
				{
					if (last[i] < 312 + UDF_SB_SESSION(sb) || !(bh = sb_bread(sb, last[i] - 312 - UDF_SB_SESSION(sb))))
					{
						ident = location = 0;
					}
					else
					{
						ident = le16_to_cpu(((tag *)bh->b_data)->tagIdent);
						location = le32_to_cpu(((tag *)bh->b_data)->tagLocation);
						udf_release_data(bh);
					}
	
					if (ident == TAG_IDENT_AVDP &&
						location == udf_variable_to_fixed(last[i]) - 256)
					{
						UDF_SET_FLAG(sb, UDF_FLAG_VARCONV);
						lastblock = udf_variable_to_fixed(last[i]);
						UDF_SB_ANCHOR(sb)[1] = lastblock - 256;
					}
				}
			}
		}
	}

	if (!lastblock)
	{
		/* We havn't found the lastblock. check 312 */
		if ((bh = sb_bread(sb, 312 + UDF_SB_SESSION(sb))))
		{
			ident = le16_to_cpu(((tag *)bh->b_data)->tagIdent);
			location = le32_to_cpu(((tag *)bh->b_data)->tagLocation);
			udf_release_data(bh);

			if (ident == TAG_IDENT_AVDP && location == 256)
				UDF_SET_FLAG(sb, UDF_FLAG_VARCONV);
		}
	}

	for (i = 0; i < ARRAY_SIZE(UDF_SB_ANCHOR(sb)); i++) {
		if (UDF_SB_ANCHOR(sb)[i])
		{
			if (!(bh = udf_read_tagged(sb,
				UDF_SB_ANCHOR(sb)[i], UDF_SB_ANCHOR(sb)[i], &ident)))
			{
				UDF_SB_ANCHOR(sb)[i] = 0;
			}
			else
			{
				udf_release_data(bh);
				if ((ident != TAG_IDENT_AVDP) && (i ||
					(ident != TAG_IDENT_FE && ident != TAG_IDENT_EFE)))
				{
					UDF_SB_ANCHOR(sb)[i] = 0;
				}
			}
		}
	}

	UDF_SB_LASTBLOCK(sb) = lastblock;
}

static int 
udf_find_fileset(struct super_block *sb, kernel_lb_addr *fileset, kernel_lb_addr *root)
{
	struct buffer_head *bh = NULL;
	long lastblock;
	uint16_t ident;

	if (fileset->logicalBlockNum != 0xFFFFFFFF ||
		fileset->partitionReferenceNum != 0xFFFF)
	{
		bh = udf_read_ptagged(sb, *fileset, 0, &ident);

		if (!bh)
			return 1;
		else if (ident != TAG_IDENT_FSD)
		{
			udf_release_data(bh);
			return 1;
		}
			
	}

	if (!bh) /* Search backwards through the partitions */
	{
		kernel_lb_addr newfileset;

		return 1;
		
		for (newfileset.partitionReferenceNum=UDF_SB_NUMPARTS(sb)-1;
			(newfileset.partitionReferenceNum != 0xFFFF &&
				fileset->logicalBlockNum == 0xFFFFFFFF &&
				fileset->partitionReferenceNum == 0xFFFF);
			newfileset.partitionReferenceNum--)
		{
			lastblock = UDF_SB_PARTLEN(sb, newfileset.partitionReferenceNum);
			newfileset.logicalBlockNum = 0;

			do
			{
				bh = udf_read_ptagged(sb, newfileset, 0, &ident);
				if (!bh)
				{
					newfileset.logicalBlockNum ++;
					continue;
				}

				switch (ident)
				{
					case TAG_IDENT_SBD:
					{
						struct spaceBitmapDesc *sp;
						sp = (struct spaceBitmapDesc *)bh->b_data;
						newfileset.logicalBlockNum += 1 +
							((le32_to_cpu(sp->numOfBytes) + sizeof(struct spaceBitmapDesc) - 1)
								>> sb->s_blocksize_bits);
						udf_release_data(bh);
						break;
					}
					case TAG_IDENT_FSD:
					{
						*fileset = newfileset;
						break;
					}
					default:
					{
						newfileset.logicalBlockNum ++;
						udf_release_data(bh);
						bh = NULL;
						break;
					}
				}
			}
			while (newfileset.logicalBlockNum < lastblock &&
				fileset->logicalBlockNum == 0xFFFFFFFF &&
				fileset->partitionReferenceNum == 0xFFFF);
		}
	}

	if ((fileset->logicalBlockNum != 0xFFFFFFFF ||
		fileset->partitionReferenceNum != 0xFFFF) && bh)
	{
		udf_debug("Fileset at block=%d, partition=%d\n",
			fileset->logicalBlockNum, fileset->partitionReferenceNum);

		UDF_SB_PARTITION(sb) = fileset->partitionReferenceNum;
		udf_load_fileset(sb, bh, root);
		udf_release_data(bh);
		return 0;
	}
	return 1;
}

static void 
udf_load_pvoldesc(struct super_block *sb, struct buffer_head *bh)
{
	struct primaryVolDesc *pvoldesc;
	time_t recording;
	long recording_usec;
	struct ustr instr;
	struct ustr outstr;

	pvoldesc = (struct primaryVolDesc *)bh->b_data;

	if ( udf_stamp_to_time(&recording, &recording_usec,
		lets_to_cpu(pvoldesc->recordingDateAndTime)) )
	{
		kernel_timestamp ts;
		ts = lets_to_cpu(pvoldesc->recordingDateAndTime);
		udf_debug("recording time %ld/%ld, %04u/%02u/%02u %02u:%02u (%x)\n",
			recording, recording_usec,
			ts.year, ts.month, ts.day, ts.hour, ts.minute, ts.typeAndTimezone);
		UDF_SB_RECORDTIME(sb).tv_sec = recording;
		UDF_SB_RECORDTIME(sb).tv_nsec = recording_usec * 1000;
	}

	if ( !udf_build_ustr(&instr, pvoldesc->volIdent, 32) )
	{
		if (udf_CS0toUTF8(&outstr, &instr))
		{
			strncpy( UDF_SB_VOLIDENT(sb), outstr.u_name,
				outstr.u_len > 31 ? 31 : outstr.u_len);
			udf_debug("volIdent[] = '%s'\n", UDF_SB_VOLIDENT(sb));
		}
	}

	if ( !udf_build_ustr(&instr, pvoldesc->volSetIdent, 128) )
	{
		if (udf_CS0toUTF8(&outstr, &instr))
			udf_debug("volSetIdent[] = '%s'\n", outstr.u_name);
	}
}

static void 
udf_load_fileset(struct super_block *sb, struct buffer_head *bh, kernel_lb_addr *root)
{
	struct fileSetDesc *fset;

	fset = (struct fileSetDesc *)bh->b_data;

	*root = lelb_to_cpu(fset->rootDirectoryICB.extLocation);

	UDF_SB_SERIALNUM(sb) = le16_to_cpu(fset->descTag.tagSerialNum);

	udf_debug("Rootdir at block=%d, partition=%d\n", 
		root->logicalBlockNum, root->partitionReferenceNum);
}

static void 
udf_load_partdesc(struct super_block *sb, struct buffer_head *bh)
{
	struct partitionDesc *p;
	int i;

	p = (struct partitionDesc *)bh->b_data;

	for (i=0; i<UDF_SB_NUMPARTS(sb); i++)
	{
		udf_debug("Searching map: (%d == %d)\n", 
			UDF_SB_PARTMAPS(sb)[i].s_partition_num, le16_to_cpu(p->partitionNumber));
		if (UDF_SB_PARTMAPS(sb)[i].s_partition_num == le16_to_cpu(p->partitionNumber))
		{
			UDF_SB_PARTLEN(sb,i) = le32_to_cpu(p->partitionLength); /* blocks */
			UDF_SB_PARTROOT(sb,i) = le32_to_cpu(p->partitionStartingLocation);
			if (le32_to_cpu(p->accessType) == PD_ACCESS_TYPE_READ_ONLY)
				UDF_SB_PARTFLAGS(sb,i) |= UDF_PART_FLAG_READ_ONLY;
			if (le32_to_cpu(p->accessType) == PD_ACCESS_TYPE_WRITE_ONCE)
				UDF_SB_PARTFLAGS(sb,i) |= UDF_PART_FLAG_WRITE_ONCE;
			if (le32_to_cpu(p->accessType) == PD_ACCESS_TYPE_REWRITABLE)
				UDF_SB_PARTFLAGS(sb,i) |= UDF_PART_FLAG_REWRITABLE;
			if (le32_to_cpu(p->accessType) == PD_ACCESS_TYPE_OVERWRITABLE)
				UDF_SB_PARTFLAGS(sb,i) |= UDF_PART_FLAG_OVERWRITABLE;

			if (!strcmp(p->partitionContents.ident, PD_PARTITION_CONTENTS_NSR02) ||
				!strcmp(p->partitionContents.ident, PD_PARTITION_CONTENTS_NSR03))
			{
				struct partitionHeaderDesc *phd;

				phd = (struct partitionHeaderDesc *)(p->partitionContentsUse);
				if (phd->unallocSpaceTable.extLength)
				{
					kernel_lb_addr loc = { le32_to_cpu(phd->unallocSpaceTable.extPosition), i };

					UDF_SB_PARTMAPS(sb)[i].s_uspace.s_table =
						udf_iget(sb, loc);
					UDF_SB_PARTFLAGS(sb,i) |= UDF_PART_FLAG_UNALLOC_TABLE;
					udf_debug("unallocSpaceTable (part %d) @ %ld\n",
						i, UDF_SB_PARTMAPS(sb)[i].s_uspace.s_table->i_ino);
				}
				if (phd->unallocSpaceBitmap.extLength)
				{
					UDF_SB_ALLOC_BITMAP(sb, i, s_uspace);
					if (UDF_SB_PARTMAPS(sb)[i].s_uspace.s_bitmap != NULL)
					{
						UDF_SB_PARTMAPS(sb)[i].s_uspace.s_bitmap->s_extLength =
							le32_to_cpu(phd->unallocSpaceBitmap.extLength);
						UDF_SB_PARTMAPS(sb)[i].s_uspace.s_bitmap->s_extPosition =
							le32_to_cpu(phd->unallocSpaceBitmap.extPosition);
						UDF_SB_PARTFLAGS(sb,i) |= UDF_PART_FLAG_UNALLOC_BITMAP;
						udf_debug("unallocSpaceBitmap (part %d) @ %d\n",
							i, UDF_SB_PARTMAPS(sb)[i].s_uspace.s_bitmap->s_extPosition);
					}
				}
				if (phd->partitionIntegrityTable.extLength)
					udf_debug("partitionIntegrityTable (part %d)\n", i);
				if (phd->freedSpaceTable.extLength)
				{
					kernel_lb_addr loc = { le32_to_cpu(phd->freedSpaceTable.extPosition), i };

					UDF_SB_PARTMAPS(sb)[i].s_fspace.s_table =
						udf_iget(sb, loc);
					UDF_SB_PARTFLAGS(sb,i) |= UDF_PART_FLAG_FREED_TABLE;
					udf_debug("freedSpaceTable (part %d) @ %ld\n",
						i, UDF_SB_PARTMAPS(sb)[i].s_fspace.s_table->i_ino);
				}
				if (phd->freedSpaceBitmap.extLength)
				{
					UDF_SB_ALLOC_BITMAP(sb, i, s_fspace);
					if (UDF_SB_PARTMAPS(sb)[i].s_fspace.s_bitmap != NULL)
					{
						UDF_SB_PARTMAPS(sb)[i].s_fspace.s_bitmap->s_extLength =
							le32_to_cpu(phd->freedSpaceBitmap.extLength);
						UDF_SB_PARTMAPS(sb)[i].s_fspace.s_bitmap->s_extPosition =
							le32_to_cpu(phd->freedSpaceBitmap.extPosition);
						UDF_SB_PARTFLAGS(sb,i) |= UDF_PART_FLAG_FREED_BITMAP;
						udf_debug("freedSpaceBitmap (part %d) @ %d\n",
							i, UDF_SB_PARTMAPS(sb)[i].s_fspace.s_bitmap->s_extPosition);
					}
				}
			}
			break;
		}
	}
	if (i == UDF_SB_NUMPARTS(sb))
	{
		udf_debug("Partition (%d) not found in partition map\n", le16_to_cpu(p->partitionNumber));
	}
	else
	{
		udf_debug("Partition (%d:%d type %x) starts at physical %d, block length %d\n",
			le16_to_cpu(p->partitionNumber), i, UDF_SB_PARTTYPE(sb,i),
			UDF_SB_PARTROOT(sb,i), UDF_SB_PARTLEN(sb,i));
	}
}

static int 
udf_load_logicalvol(struct super_block *sb, struct buffer_head * bh, kernel_lb_addr *fileset)
{
	struct logicalVolDesc *lvd;
	int i, j, offset;
	uint8_t type;

	lvd = (struct logicalVolDesc *)bh->b_data;

	UDF_SB_ALLOC_PARTMAPS(sb, le32_to_cpu(lvd->numPartitionMaps));

	for (i=0,offset=0;
		 i<UDF_SB_NUMPARTS(sb) && offset<le32_to_cpu(lvd->mapTableLength);
		 i++,offset+=((struct genericPartitionMap *)&(lvd->partitionMaps[offset]))->partitionMapLength)
	{
		type = ((struct genericPartitionMap *)&(lvd->partitionMaps[offset]))->partitionMapType;
		if (type == 1)
		{
			struct genericPartitionMap1 *gpm1 = (struct genericPartitionMap1 *)&(lvd->partitionMaps[offset]);
			UDF_SB_PARTTYPE(sb,i) = UDF_TYPE1_MAP15;
			UDF_SB_PARTVSN(sb,i) = le16_to_cpu(gpm1->volSeqNum);
			UDF_SB_PARTNUM(sb,i) = le16_to_cpu(gpm1->partitionNum);
			UDF_SB_PARTFUNC(sb,i) = NULL;
		}
		else if (type == 2)
		{
			struct udfPartitionMap2 *upm2 = (struct udfPartitionMap2 *)&(lvd->partitionMaps[offset]);
			if (!strncmp(upm2->partIdent.ident, UDF_ID_VIRTUAL, strlen(UDF_ID_VIRTUAL)))
			{
				if (le16_to_cpu(((__le16 *)upm2->partIdent.identSuffix)[0]) == 0x0150)
				{
					UDF_SB_PARTTYPE(sb,i) = UDF_VIRTUAL_MAP15;
					UDF_SB_PARTFUNC(sb,i) = udf_get_pblock_virt15;
				}
				else if (le16_to_cpu(((__le16 *)upm2->partIdent.identSuffix)[0]) == 0x0200)
				{
					UDF_SB_PARTTYPE(sb,i) = UDF_VIRTUAL_MAP20;
					UDF_SB_PARTFUNC(sb,i) = udf_get_pblock_virt20;
				}
			}
			else if (!strncmp(upm2->partIdent.ident, UDF_ID_SPARABLE, strlen(UDF_ID_SPARABLE)))
			{
				uint32_t loc;
				uint16_t ident;
				struct sparingTable *st;
				struct sparablePartitionMap *spm = (struct sparablePartitionMap *)&(lvd->partitionMaps[offset]);

				UDF_SB_PARTTYPE(sb,i) = UDF_SPARABLE_MAP15;
				UDF_SB_TYPESPAR(sb,i).s_packet_len = le16_to_cpu(spm->packetLength);
				for (j=0; j<spm->numSparingTables; j++)
				{
					loc = le32_to_cpu(spm->locSparingTable[j]);
					UDF_SB_TYPESPAR(sb,i).s_spar_map[j] =
						udf_read_tagged(sb, loc, loc, &ident);
					if (UDF_SB_TYPESPAR(sb,i).s_spar_map[j] != NULL)
					{
						st = (struct sparingTable *)UDF_SB_TYPESPAR(sb,i).s_spar_map[j]->b_data;
						if (ident != 0 ||
							strncmp(st->sparingIdent.ident, UDF_ID_SPARING, strlen(UDF_ID_SPARING)))
						{
							udf_release_data(UDF_SB_TYPESPAR(sb,i).s_spar_map[j]);
							UDF_SB_TYPESPAR(sb,i).s_spar_map[j] = NULL;
						}
					}
				}
				UDF_SB_PARTFUNC(sb,i) = udf_get_pblock_spar15;
			}
			else
			{
				udf_debug("Unknown ident: %s\n", upm2->partIdent.ident);
				continue;
			}
			UDF_SB_PARTVSN(sb,i) = le16_to_cpu(upm2->volSeqNum);
			UDF_SB_PARTNUM(sb,i) = le16_to_cpu(upm2->partitionNum);
		}
		udf_debug("Partition (%d:%d) type %d on volume %d\n",
			i, UDF_SB_PARTNUM(sb,i), type, UDF_SB_PARTVSN(sb,i));
	}

	if (fileset)
	{
		long_ad *la = (long_ad *)&(lvd->logicalVolContentsUse[0]);

		*fileset = lelb_to_cpu(la->extLocation);
		udf_debug("FileSet found in LogicalVolDesc at block=%d, partition=%d\n",
			fileset->logicalBlockNum,
			fileset->partitionReferenceNum);
	}
	if (lvd->integritySeqExt.extLength)
		udf_load_logicalvolint(sb, leea_to_cpu(lvd->integritySeqExt));
	return 0;
}

/*
 * udf_load_logicalvolint
 *
 */
static void
udf_load_logicalvolint(struct super_block *sb, kernel_extent_ad loc)
{
	struct buffer_head *bh = NULL;
	uint16_t ident;

	while (loc.extLength > 0 &&
		(bh = udf_read_tagged(sb, loc.extLocation,
			loc.extLocation, &ident)) &&
		ident == TAG_IDENT_LVID)
	{
		UDF_SB_LVIDBH(sb) = bh;
		
		if (UDF_SB_LVID(sb)->nextIntegrityExt.extLength)
			udf_load_logicalvolint(sb, leea_to_cpu(UDF_SB_LVID(sb)->nextIntegrityExt));
		
		if (UDF_SB_LVIDBH(sb) != bh)
			udf_release_data(bh);
		loc.extLength -= sb->s_blocksize;
		loc.extLocation ++;
	}
	if (UDF_SB_LVIDBH(sb) != bh)
		udf_release_data(bh);
}

/*
 * udf_process_sequence
 *
 * PURPOSE
 *	Process a main/reserve volume descriptor sequence.
 *
 * PRE-CONDITIONS
 *	sb			Pointer to _locked_ superblock.
 *	block			First block of first extent of the sequence.
 *	lastblock		Lastblock of first extent of the sequence.
 *
 * HISTORY
 *	July 1, 1997 - Andrew E. Mileski
 *	Written, tested, and released.
 */
static  int
udf_process_sequence(struct super_block *sb, long block, long lastblock, kernel_lb_addr *fileset)
{
	struct buffer_head *bh = NULL;
	struct udf_vds_record vds[VDS_POS_LENGTH];
	struct generic_desc *gd;
	struct volDescPtr *vdp;
	int done=0;
	int i,j;
	uint32_t vdsn;
	uint16_t ident;
	long next_s = 0, next_e = 0;

	memset(vds, 0, sizeof(struct udf_vds_record) * VDS_POS_LENGTH);

	/* Read the main descriptor sequence */
	for (;(!done && block <= lastblock); block++)
	{

		bh = udf_read_tagged(sb, block, block, &ident);
		if (!bh) 
			break;

		/* Process each descriptor (ISO 13346 3/8.3-8.4) */
		gd = (struct generic_desc *)bh->b_data;
		vdsn = le32_to_cpu(gd->volDescSeqNum);
		switch (ident)
		{
			case TAG_IDENT_PVD: /* ISO 13346 3/10.1 */
				if (vdsn >= vds[VDS_POS_PRIMARY_VOL_DESC].volDescSeqNum)
				{
					vds[VDS_POS_PRIMARY_VOL_DESC].volDescSeqNum = vdsn;
					vds[VDS_POS_PRIMARY_VOL_DESC].block = block;
				}
				break;
			case TAG_IDENT_VDP: /* ISO 13346 3/10.3 */
				if (vdsn >= vds[VDS_POS_VOL_DESC_PTR].volDescSeqNum)
				{
					vds[VDS_POS_VOL_DESC_PTR].volDescSeqNum = vdsn;
					vds[VDS_POS_VOL_DESC_PTR].block = block;

					vdp = (struct volDescPtr *)bh->b_data;
					next_s = le32_to_cpu(vdp->nextVolDescSeqExt.extLocation);
					next_e = le32_to_cpu(vdp->nextVolDescSeqExt.extLength);
					next_e = next_e >> sb->s_blocksize_bits;
					next_e += next_s;
				}
				break;
			case TAG_IDENT_IUVD: /* ISO 13346 3/10.4 */
				if (vdsn >= vds[VDS_POS_IMP_USE_VOL_DESC].volDescSeqNum)
				{
					vds[VDS_POS_IMP_USE_VOL_DESC].volDescSeqNum = vdsn;
					vds[VDS_POS_IMP_USE_VOL_DESC].block = block;
				}
				break;
			case TAG_IDENT_PD: /* ISO 13346 3/10.5 */
				if (!vds[VDS_POS_PARTITION_DESC].block)
					vds[VDS_POS_PARTITION_DESC].block = block;
				break;
			case TAG_IDENT_LVD: /* ISO 13346 3/10.6 */
				if (vdsn >= vds[VDS_POS_LOGICAL_VOL_DESC].volDescSeqNum)
				{
					vds[VDS_POS_LOGICAL_VOL_DESC].volDescSeqNum = vdsn;
					vds[VDS_POS_LOGICAL_VOL_DESC].block = block;
				}
				break;
			case TAG_IDENT_USD: /* ISO 13346 3/10.8 */
				if (vdsn >= vds[VDS_POS_UNALLOC_SPACE_DESC].volDescSeqNum)
				{
					vds[VDS_POS_UNALLOC_SPACE_DESC].volDescSeqNum = vdsn;
					vds[VDS_POS_UNALLOC_SPACE_DESC].block = block;
				}
				break;
			case TAG_IDENT_TD: /* ISO 13346 3/10.9 */
				vds[VDS_POS_TERMINATING_DESC].block = block;
				if (next_e)
				{
					block = next_s;
					lastblock = next_e;
					next_s = next_e = 0;
				}
				else
					done = 1;
				break;
		}
		udf_release_data(bh);
	}
	for (i=0; i<VDS_POS_LENGTH; i++)
	{
		if (vds[i].block)
		{
			bh = udf_read_tagged(sb, vds[i].block, vds[i].block, &ident);

			if (i == VDS_POS_PRIMARY_VOL_DESC)
				udf_load_pvoldesc(sb, bh);
			else if (i == VDS_POS_LOGICAL_VOL_DESC)
				udf_load_logicalvol(sb, bh, fileset);
			else if (i == VDS_POS_PARTITION_DESC)
			{
				struct buffer_head *bh2 = NULL;
				udf_load_partdesc(sb, bh);
				for (j=vds[i].block+1; j<vds[VDS_POS_TERMINATING_DESC].block; j++)
				{
					bh2 = udf_read_tagged(sb, j, j, &ident);
					gd = (struct generic_desc *)bh2->b_data;
					if (ident == TAG_IDENT_PD)
						udf_load_partdesc(sb, bh2);
					udf_release_data(bh2);
				}
			}
			udf_release_data(bh);
		}
	}

	return 0;
}

/*
 * udf_check_valid()
 */
static int
udf_check_valid(struct super_block *sb, int novrs, int silent)
{
	long block;

	if (novrs)
	{
		udf_debug("Validity check skipped because of novrs option\n");
		return 0;
	}
	/* Check that it is NSR02 compliant */
	/* Process any "CD-ROM Volume Descriptor Set" (ECMA 167 2/8.3.1) */
	else if ((block = udf_vrs(sb, silent)) == -1)
	{
		udf_debug("Failed to read byte 32768. Assuming open disc. Skipping validity check\n");
		if (!UDF_SB_LASTBLOCK(sb))
			UDF_SB_LASTBLOCK(sb) = udf_get_last_block(sb);
		return 0;
	}
	else 
		return !block;
}

static int
udf_load_partition(struct super_block *sb, kernel_lb_addr *fileset)
{
	struct anchorVolDescPtr *anchor;
	uint16_t ident;
	struct buffer_head *bh;
	long main_s, main_e, reserve_s, reserve_e;
	int i, j;

	if (!sb)
		return 1;

	for (i = 0; i < ARRAY_SIZE(UDF_SB_ANCHOR(sb)); i++) {
		if (UDF_SB_ANCHOR(sb)[i] && (bh = udf_read_tagged(sb,
			UDF_SB_ANCHOR(sb)[i], UDF_SB_ANCHOR(sb)[i], &ident)))
		{
			anchor = (struct anchorVolDescPtr *)bh->b_data;

			/* Locate the main sequence */
			main_s = le32_to_cpu( anchor->mainVolDescSeqExt.extLocation );
			main_e = le32_to_cpu( anchor->mainVolDescSeqExt.extLength );
			main_e = main_e >> sb->s_blocksize_bits;
			main_e += main_s;

			/* Locate the reserve sequence */
			reserve_s = le32_to_cpu(anchor->reserveVolDescSeqExt.extLocation);
			reserve_e = le32_to_cpu(anchor->reserveVolDescSeqExt.extLength);
			reserve_e = reserve_e >> sb->s_blocksize_bits;
			reserve_e += reserve_s;

			udf_release_data(bh);

			/* Process the main & reserve sequences */
			/* responsible for finding the PartitionDesc(s) */
			if (!(udf_process_sequence(sb, main_s, main_e, fileset) &&
				udf_process_sequence(sb, reserve_s, reserve_e, fileset)))
			{
				break;
			}
		}
	}

	if (i == ARRAY_SIZE(UDF_SB_ANCHOR(sb))) {
		udf_debug("No Anchor block found\n");
		return 1;
	} else
		udf_debug("Using anchor in block %d\n", UDF_SB_ANCHOR(sb)[i]);

	for (i=0; i<UDF_SB_NUMPARTS(sb); i++)
	{
		switch UDF_SB_PARTTYPE(sb, i)
		{
			case UDF_VIRTUAL_MAP15:
			case UDF_VIRTUAL_MAP20:
			{
				kernel_lb_addr ino;

				if (!UDF_SB_LASTBLOCK(sb))
				{
					UDF_SB_LASTBLOCK(sb) = udf_get_last_block(sb);
					udf_find_anchor(sb);
				}

				if (!UDF_SB_LASTBLOCK(sb))
				{
					udf_debug("Unable to determine Lastblock (For Virtual Partition)\n");
					return 1;
				}

				for (j=0; j<UDF_SB_NUMPARTS(sb); j++)
				{
					if (j != i &&
						UDF_SB_PARTVSN(sb,i) == UDF_SB_PARTVSN(sb,j) &&
						UDF_SB_PARTNUM(sb,i) == UDF_SB_PARTNUM(sb,j))
					{
						ino.partitionReferenceNum = j;
						ino.logicalBlockNum = UDF_SB_LASTBLOCK(sb) -
							UDF_SB_PARTROOT(sb,j);
						break;
					}
				}

				if (j == UDF_SB_NUMPARTS(sb))
					return 1;

				if (!(UDF_SB_VAT(sb) = udf_iget(sb, ino)))
					return 1;

				if (UDF_SB_PARTTYPE(sb,i) == UDF_VIRTUAL_MAP15)
				{
					UDF_SB_TYPEVIRT(sb,i).s_start_offset = udf_ext0_offset(UDF_SB_VAT(sb));
					UDF_SB_TYPEVIRT(sb,i).s_num_entries = (UDF_SB_VAT(sb)->i_size - 36) >> 2;
				}
				else if (UDF_SB_PARTTYPE(sb,i) == UDF_VIRTUAL_MAP20)
				{
					struct buffer_head *bh = NULL;
					uint32_t pos;

					pos = udf_block_map(UDF_SB_VAT(sb), 0);
					bh = sb_bread(sb, pos);
					UDF_SB_TYPEVIRT(sb,i).s_start_offset =
						le16_to_cpu(((struct virtualAllocationTable20 *)bh->b_data + udf_ext0_offset(UDF_SB_VAT(sb)))->lengthHeader) +
							udf_ext0_offset(UDF_SB_VAT(sb));
					UDF_SB_TYPEVIRT(sb,i).s_num_entries = (UDF_SB_VAT(sb)->i_size -
						UDF_SB_TYPEVIRT(sb,i).s_start_offset) >> 2;
					udf_release_data(bh);
				}
				UDF_SB_PARTROOT(sb,i) = udf_get_pblock(sb, 0, i, 0);
				UDF_SB_PARTLEN(sb,i) = UDF_SB_PARTLEN(sb,ino.partitionReferenceNum);
			}
		}
	}
	return 0;
}

static void udf_open_lvid(struct super_block *sb)
{
	if (UDF_SB_LVIDBH(sb))
	{
		int i;
		kernel_timestamp cpu_time;

		UDF_SB_LVIDIU(sb)->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
		UDF_SB_LVIDIU(sb)->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
		if (udf_time_to_stamp(&cpu_time, CURRENT_TIME))
			UDF_SB_LVID(sb)->recordingDateAndTime = cpu_to_lets(cpu_time);
		UDF_SB_LVID(sb)->integrityType = LVID_INTEGRITY_TYPE_OPEN;

		UDF_SB_LVID(sb)->descTag.descCRC =
			cpu_to_le16(udf_crc((char *)UDF_SB_LVID(sb) + sizeof(tag),
			le16_to_cpu(UDF_SB_LVID(sb)->descTag.descCRCLength), 0));

		UDF_SB_LVID(sb)->descTag.tagChecksum = 0;
		for (i=0; i<16; i++)
			if (i != 4)
				UDF_SB_LVID(sb)->descTag.tagChecksum +=
					((uint8_t *)&(UDF_SB_LVID(sb)->descTag))[i];

		mark_buffer_dirty(UDF_SB_LVIDBH(sb));
	}
}

static void udf_close_lvid(struct super_block *sb)
{
	if (UDF_SB_LVIDBH(sb) &&
		UDF_SB_LVID(sb)->integrityType == LVID_INTEGRITY_TYPE_OPEN)
	{
		int i;
		kernel_timestamp cpu_time;

		UDF_SB_LVIDIU(sb)->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
		UDF_SB_LVIDIU(sb)->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
		if (udf_time_to_stamp(&cpu_time, CURRENT_TIME))
			UDF_SB_LVID(sb)->recordingDateAndTime = cpu_to_lets(cpu_time);
		if (UDF_MAX_WRITE_VERSION > le16_to_cpu(UDF_SB_LVIDIU(sb)->maxUDFWriteRev))
			UDF_SB_LVIDIU(sb)->maxUDFWriteRev = cpu_to_le16(UDF_MAX_WRITE_VERSION);
		if (UDF_SB_UDFREV(sb) > le16_to_cpu(UDF_SB_LVIDIU(sb)->minUDFReadRev))
			UDF_SB_LVIDIU(sb)->minUDFReadRev = cpu_to_le16(UDF_SB_UDFREV(sb));
		if (UDF_SB_UDFREV(sb) > le16_to_cpu(UDF_SB_LVIDIU(sb)->minUDFWriteRev))
			UDF_SB_LVIDIU(sb)->minUDFWriteRev = cpu_to_le16(UDF_SB_UDFREV(sb));
		UDF_SB_LVID(sb)->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_CLOSE);

		UDF_SB_LVID(sb)->descTag.descCRC =
			cpu_to_le16(udf_crc((char *)UDF_SB_LVID(sb) + sizeof(tag),
			le16_to_cpu(UDF_SB_LVID(sb)->descTag.descCRCLength), 0));

		UDF_SB_LVID(sb)->descTag.tagChecksum = 0;
		for (i=0; i<16; i++)
			if (i != 4)
				UDF_SB_LVID(sb)->descTag.tagChecksum +=
					((uint8_t *)&(UDF_SB_LVID(sb)->descTag))[i];

		mark_buffer_dirty(UDF_SB_LVIDBH(sb));
	}
}

/*
 * udf_read_super
 *
 * PURPOSE
 *	Complete the specified super block.
 *
 * PRE-CONDITIONS
 *	sb			Pointer to superblock to complete - never NULL.
 *	sb->s_dev		Device to read suberblock from.
 *	options			Pointer to mount options.
 *	silent			Silent flag.
 *
 * HISTORY
 *	July 1, 1997 - Andrew E. Mileski
 *	Written, tested, and released.
 */
static int udf_fill_super(struct super_block *sb, void *options, int silent)
{
	int i;
	struct inode *inode=NULL;
	struct udf_options uopt;
	kernel_lb_addr rootdir, fileset;
	struct udf_sb_info *sbi;

	uopt.flags = (1 << UDF_FLAG_USE_AD_IN_ICB) | (1 << UDF_FLAG_STRICT);
	uopt.uid = -1;
	uopt.gid = -1;
	uopt.umask = 0;

	sbi = kmalloc(sizeof(struct udf_sb_info), GFP_KERNEL);
	if (!sbi)
		return -ENOMEM;
	sb->s_fs_info = sbi;
	memset(UDF_SB(sb), 0x00, sizeof(struct udf_sb_info));

	mutex_init(&sbi->s_alloc_mutex);

	if (!udf_parse_options((char *)options, &uopt))
		goto error_out;

	if (uopt.flags & (1 << UDF_FLAG_UTF8) &&
	    uopt.flags & (1 << UDF_FLAG_NLS_MAP))
	{
		udf_error(sb, "udf_read_super",
			"utf8 cannot be combined with iocharset\n");
		goto error_out;
	}
#ifdef CONFIG_UDF_NLS
	if ((uopt.flags & (1 << UDF_FLAG_NLS_MAP)) && !uopt.nls_map)
	{
		uopt.nls_map = load_nls_default();
		if (!uopt.nls_map)
			uopt.flags &= ~(1 << UDF_FLAG_NLS_MAP);
		else
			udf_debug("Using default NLS map\n");
	}
#endif
	if (!(uopt.flags & (1 << UDF_FLAG_NLS_MAP)))
		uopt.flags |= (1 << UDF_FLAG_UTF8);

	fileset.logicalBlockNum = 0xFFFFFFFF;
	fileset.partitionReferenceNum = 0xFFFF;

	UDF_SB(sb)->s_flags = uopt.flags;
	UDF_SB(sb)->s_uid = uopt.uid;
	UDF_SB(sb)->s_gid = uopt.gid;
	UDF_SB(sb)->s_umask = uopt.umask;
	UDF_SB(sb)->s_nls_map = uopt.nls_map;

	/* Set the block size for all transfers */
	if (!udf_set_blocksize(sb, uopt.blocksize))
		goto error_out;

	if ( uopt.session == 0xFFFFFFFF )
		UDF_SB_SESSION(sb) = udf_get_last_session(sb);
	else
		UDF_SB_SESSION(sb) = uopt.session;

	udf_debug("Multi-session=%d\n", UDF_SB_SESSION(sb));

	UDF_SB_LASTBLOCK(sb) = uopt.lastblock;
	UDF_SB_ANCHOR(sb)[0] = UDF_SB_ANCHOR(sb)[1] = 0;
	UDF_SB_ANCHOR(sb)[2] = uopt.anchor;
	UDF_SB_ANCHOR(sb)[3] = 256;

	if (udf_check_valid(sb, uopt.novrs, silent)) /* read volume recognition sequences */
	{
		printk("UDF-fs: No VRS found\n");
 		goto error_out;
	}

	udf_find_anchor(sb);

	/* Fill in the rest of the superblock */
	sb->s_op = &udf_sb_ops;
	sb->dq_op = NULL;
	sb->s_dirt = 0;
	sb->s_magic = UDF_SUPER_MAGIC;
	sb->s_time_gran = 1000;

	if (udf_load_partition(sb, &fileset))
	{
		printk("UDF-fs: No partition found (1)\n");
		goto error_out;
	}

	udf_debug("Lastblock=%d\n", UDF_SB_LASTBLOCK(sb));

	if ( UDF_SB_LVIDBH(sb) )
	{
		uint16_t minUDFReadRev = le16_to_cpu(UDF_SB_LVIDIU(sb)->minUDFReadRev);
		uint16_t minUDFWriteRev = le16_to_cpu(UDF_SB_LVIDIU(sb)->minUDFWriteRev);
		/* uint16_t maxUDFWriteRev = le16_to_cpu(UDF_SB_LVIDIU(sb)->maxUDFWriteRev); */

		if (minUDFReadRev > UDF_MAX_READ_VERSION)
		{
			printk("UDF-fs: minUDFReadRev=%x (max is %x)\n",
				le16_to_cpu(UDF_SB_LVIDIU(sb)->minUDFReadRev),
				UDF_MAX_READ_VERSION);
			goto error_out;
		}
		else if (minUDFWriteRev > UDF_MAX_WRITE_VERSION)
		{
			sb->s_flags |= MS_RDONLY;
		}

		UDF_SB_UDFREV(sb) = minUDFWriteRev;

		if (minUDFReadRev >= UDF_VERS_USE_EXTENDED_FE)
			UDF_SET_FLAG(sb, UDF_FLAG_USE_EXTENDED_FE);
		if (minUDFReadRev >= UDF_VERS_USE_STREAMS)
			UDF_SET_FLAG(sb, UDF_FLAG_USE_STREAMS);
	}

	if ( !UDF_SB_NUMPARTS(sb) )
	{
		printk("UDF-fs: No partition found (2)\n");
		goto error_out;
	}

	if ( udf_find_fileset(sb, &fileset, &rootdir) )
	{
		printk("UDF-fs: No fileset found\n");
		goto error_out;
	}

	if (!silent)
	{
		kernel_timestamp ts;
		udf_time_to_stamp(&ts, UDF_SB_RECORDTIME(sb));
		udf_info("UDF %s (%s) Mounting volume '%s', timestamp %04u/%02u/%02u %02u:%02u (%x)\n",
			UDFFS_VERSION, UDFFS_DATE,
			UDF_SB_VOLIDENT(sb), ts.year, ts.month, ts.day, ts.hour, ts.minute,
			ts.typeAndTimezone);
	}
	if (!(sb->s_flags & MS_RDONLY))
		udf_open_lvid(sb);

	/* Assign the root inode */
	/* assign inodes by physical block number */
	/* perhaps it's not extensible enough, but for now ... */
	inode = udf_iget(sb, rootdir); 
	if (!inode)
	{
		printk("UDF-fs: Error in udf_iget, block=%d, partition=%d\n",
			rootdir.logicalBlockNum, rootdir.partitionReferenceNum);
		goto error_out;
	}

	/* Allocate a dentry for the root inode */
	sb->s_root = d_alloc_root(inode);
	if (!sb->s_root)
	{
		printk("UDF-fs: Couldn't allocate root dentry\n");
		iput(inode);
		goto error_out;
	}
	sb->s_maxbytes = MAX_LFS_FILESIZE;
	return 0;

error_out:
	if (UDF_SB_VAT(sb))
		iput(UDF_SB_VAT(sb));
	if (UDF_SB_NUMPARTS(sb))
	{
		if (UDF_SB_PARTFLAGS(sb, UDF_SB_PARTITION(sb)) & UDF_PART_FLAG_UNALLOC_TABLE)
			iput(UDF_SB_PARTMAPS(sb)[UDF_SB_PARTITION(sb)].s_uspace.s_table);
		if (UDF_SB_PARTFLAGS(sb, UDF_SB_PARTITION(sb)) & UDF_PART_FLAG_FREED_TABLE)
			iput(UDF_SB_PARTMAPS(sb)[UDF_SB_PARTITION(sb)].s_fspace.s_table);
		if (UDF_SB_PARTFLAGS(sb, UDF_SB_PARTITION(sb)) & UDF_PART_FLAG_UNALLOC_BITMAP)
			UDF_SB_FREE_BITMAP(sb,UDF_SB_PARTITION(sb),s_uspace);
		if (UDF_SB_PARTFLAGS(sb, UDF_SB_PARTITION(sb)) & UDF_PART_FLAG_FREED_BITMAP)
			UDF_SB_FREE_BITMAP(sb,UDF_SB_PARTITION(sb),s_fspace);
		if (UDF_SB_PARTTYPE(sb, UDF_SB_PARTITION(sb)) == UDF_SPARABLE_MAP15)
		{
			for (i=0; i<4; i++)
				udf_release_data(UDF_SB_TYPESPAR(sb, UDF_SB_PARTITION(sb)).s_spar_map[i]);
		}
	}
#ifdef CONFIG_UDF_NLS
	if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP))
		unload_nls(UDF_SB(sb)->s_nls_map);
#endif
	if (!(sb->s_flags & MS_RDONLY))
		udf_close_lvid(sb);
	udf_release_data(UDF_SB_LVIDBH(sb));
	UDF_SB_FREE(sb);
	kfree(sbi);
	sb->s_fs_info = NULL;
	return -EINVAL;
}

void udf_error(struct super_block *sb, const char *function,
	const char *fmt, ...)
{
	va_list args;

	if (!(sb->s_flags & MS_RDONLY))
	{
		/* mark sb error */
		sb->s_dirt = 1;
	}
	va_start(args, fmt);
	vsprintf(error_buf, fmt, args);
	va_end(args);
	printk (KERN_CRIT "UDF-fs error (device %s): %s: %s\n",
		sb->s_id, function, error_buf);
}

void udf_warning(struct super_block *sb, const char *function,
	const char *fmt, ...)
{
	va_list args;

	va_start (args, fmt);
	vsprintf(error_buf, fmt, args);
	va_end(args);
	printk(KERN_WARNING "UDF-fs warning (device %s): %s: %s\n",
		sb->s_id, function, error_buf);
}

/*
 * udf_put_super
 *
 * PURPOSE
 *	Prepare for destruction of the superblock.
 *
 * DESCRIPTION
 *	Called before the filesystem is unmounted.
 *
 * HISTORY
 *	July 1, 1997 - Andrew E. Mileski
 *	Written, tested, and released.
 */
static void
udf_put_super(struct super_block *sb)
{
	int i;

	if (UDF_SB_VAT(sb))
		iput(UDF_SB_VAT(sb));
	if (UDF_SB_NUMPARTS(sb))
	{
		if (UDF_SB_PARTFLAGS(sb, UDF_SB_PARTITION(sb)) & UDF_PART_FLAG_UNALLOC_TABLE)
			iput(UDF_SB_PARTMAPS(sb)[UDF_SB_PARTITION(sb)].s_uspace.s_table);
		if (UDF_SB_PARTFLAGS(sb, UDF_SB_PARTITION(sb)) & UDF_PART_FLAG_FREED_TABLE)
			iput(UDF_SB_PARTMAPS(sb)[UDF_SB_PARTITION(sb)].s_fspace.s_table);
		if (UDF_SB_PARTFLAGS(sb, UDF_SB_PARTITION(sb)) & UDF_PART_FLAG_UNALLOC_BITMAP)
			UDF_SB_FREE_BITMAP(sb,UDF_SB_PARTITION(sb),s_uspace);
		if (UDF_SB_PARTFLAGS(sb, UDF_SB_PARTITION(sb)) & UDF_PART_FLAG_FREED_BITMAP)
			UDF_SB_FREE_BITMAP(sb,UDF_SB_PARTITION(sb),s_fspace);
		if (UDF_SB_PARTTYPE(sb, UDF_SB_PARTITION(sb)) == UDF_SPARABLE_MAP15)
		{
			for (i=0; i<4; i++)
				udf_release_data(UDF_SB_TYPESPAR(sb, UDF_SB_PARTITION(sb)).s_spar_map[i]);
		}
	}
#ifdef CONFIG_UDF_NLS
	if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP))
		unload_nls(UDF_SB(sb)->s_nls_map);
#endif
	if (!(sb->s_flags & MS_RDONLY))
		udf_close_lvid(sb);
	udf_release_data(UDF_SB_LVIDBH(sb));
	UDF_SB_FREE(sb);
	kfree(sb->s_fs_info);
	sb->s_fs_info = NULL;
}

/*
 * udf_stat_fs
 *
 * PURPOSE
 *	Return info about the filesystem.
 *
 * DESCRIPTION
 *	Called by sys_statfs()
 *
 * HISTORY
 *	July 1, 1997 - Andrew E. Mileski
 *	Written, tested, and released.
 */
static int
udf_statfs(struct dentry *dentry, struct kstatfs *buf)
{
	struct super_block *sb = dentry->d_sb;

	buf->f_type = UDF_SUPER_MAGIC;
	buf->f_bsize = sb->s_blocksize;
	buf->f_blocks = UDF_SB_PARTLEN(sb, UDF_SB_PARTITION(sb));
	buf->f_bfree = udf_count_free(sb);
	buf->f_bavail = buf->f_bfree;
	buf->f_files = (UDF_SB_LVIDBH(sb) ?
		(le32_to_cpu(UDF_SB_LVIDIU(sb)->numFiles) +
		le32_to_cpu(UDF_SB_LVIDIU(sb)->numDirs)) : 0) + buf->f_bfree;
	buf->f_ffree = buf->f_bfree;
	/* __kernel_fsid_t f_fsid */
	buf->f_namelen = UDF_NAME_LEN-2;

	return 0;
}

static unsigned char udf_bitmap_lookup[16] = {
	0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4
};

static unsigned int
udf_count_free_bitmap(struct super_block *sb, struct udf_bitmap *bitmap)
{
	struct buffer_head *bh = NULL;
	unsigned int accum = 0;
	int index;
	int block = 0, newblock;
	kernel_lb_addr loc;
	uint32_t bytes;
	uint8_t value;
	uint8_t *ptr;
	uint16_t ident;
	struct spaceBitmapDesc *bm;

	lock_kernel();

	loc.logicalBlockNum = bitmap->s_extPosition;
	loc.partitionReferenceNum = UDF_SB_PARTITION(sb);
	bh = udf_read_ptagged(sb, loc, 0, &ident);

	if (!bh)
	{
		printk(KERN_ERR "udf: udf_count_free failed\n");
		goto out;
	}
	else if (ident != TAG_IDENT_SBD)
	{
		udf_release_data(bh);
		printk(KERN_ERR "udf: udf_count_free failed\n");
		goto out;
	}

	bm = (struct spaceBitmapDesc *)bh->b_data;
	bytes = le32_to_cpu(bm->numOfBytes);
	index = sizeof(struct spaceBitmapDesc); /* offset in first block only */
	ptr = (uint8_t *)bh->b_data;

	while ( bytes > 0 )
	{
		while ((bytes > 0) && (index < sb->s_blocksize))
		{
			value = ptr[index];
			accum += udf_bitmap_lookup[ value & 0x0f ];
			accum += udf_bitmap_lookup[ value >> 4 ];
			index++;
			bytes--;
		}
		if ( bytes )
		{
			udf_release_data(bh);
			newblock = udf_get_lb_pblock(sb, loc, ++block);
			bh = udf_tread(sb, newblock);
			if (!bh)
			{
				udf_debug("read failed\n");
				goto out;
			}
			index = 0;
			ptr = (uint8_t *)bh->b_data;
		}
	}
	udf_release_data(bh);

out:
	unlock_kernel();

	return accum;
}

static unsigned int
udf_count_free_table(struct super_block *sb, struct inode * table)
{
	unsigned int accum = 0;
	uint32_t extoffset, elen;
	kernel_lb_addr bloc, eloc;
	int8_t etype;
	struct buffer_head *bh = NULL;

	lock_kernel();

	bloc = UDF_I_LOCATION(table);
	extoffset = sizeof(struct unallocSpaceEntry);

	while ((etype = udf_next_aext(table, &bloc, &extoffset, &eloc, &elen, &bh, 1)) != -1)
	{
		accum += (elen >> table->i_sb->s_blocksize_bits);
	}
	udf_release_data(bh);

	unlock_kernel();

	return accum;
}
	
static unsigned int
udf_count_free(struct super_block *sb)
{
	unsigned int accum = 0;

	if (UDF_SB_LVIDBH(sb))
	{
		if (le32_to_cpu(UDF_SB_LVID(sb)->numOfPartitions) > UDF_SB_PARTITION(sb))
		{
			accum = le32_to_cpu(UDF_SB_LVID(sb)->freeSpaceTable[UDF_SB_PARTITION(sb)]);

			if (accum == 0xFFFFFFFF)
				accum = 0;
		}
	}

	if (accum)
		return accum;

	if (UDF_SB_PARTFLAGS(sb,UDF_SB_PARTITION(sb)) & UDF_PART_FLAG_UNALLOC_BITMAP)
	{
		accum += udf_count_free_bitmap(sb,
			UDF_SB_PARTMAPS(sb)[UDF_SB_PARTITION(sb)].s_uspace.s_bitmap);
	}
	if (UDF_SB_PARTFLAGS(sb,UDF_SB_PARTITION(sb)) & UDF_PART_FLAG_FREED_BITMAP)
	{
		accum += udf_count_free_bitmap(sb,
			UDF_SB_PARTMAPS(sb)[UDF_SB_PARTITION(sb)].s_fspace.s_bitmap);
	}
	if (accum)
		return accum;

	if (UDF_SB_PARTFLAGS(sb,UDF_SB_PARTITION(sb)) & UDF_PART_FLAG_UNALLOC_TABLE)
	{
		accum += udf_count_free_table(sb,
			UDF_SB_PARTMAPS(sb)[UDF_SB_PARTITION(sb)].s_uspace.s_table);
	}
	if (UDF_SB_PARTFLAGS(sb,UDF_SB_PARTITION(sb)) & UDF_PART_FLAG_FREED_TABLE)
	{
		accum += udf_count_free_table(sb,
			UDF_SB_PARTMAPS(sb)[UDF_SB_PARTITION(sb)].s_fspace.s_table);
	}

	return accum;
}