super.c

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		{
			lastblock = last[i];
			UDF_SB_ANCHOR(sb)[2] = 512 + UDF_SB_SESSION(sb);
		}
		else
		{
			if (!(bh = bread(sb->s_dev, last[i] - 256, sb->s_blocksize)))
			{
				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 == TID_ANCHOR_VOL_DESC_PTR &&
				location == last[i] - 256 - UDF_SB_SESSION(sb))
			{
				lastblock = last[i];
				UDF_SB_ANCHOR(sb)[1] = last[i] - 256;
			}
			else
			{
				if (!(bh = bread(sb->s_dev, last[i] - 312 - UDF_SB_SESSION(sb),
					sb->s_blocksize)))
				{
					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 == TID_ANCHOR_VOL_DESC_PTR &&
					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 = bread(sb->s_dev, 312 + UDF_SB_SESSION(sb), sb->s_blocksize)))
		{
			ident = le16_to_cpu(((tag *)bh->b_data)->tagIdent);
			location = le32_to_cpu(((tag *)bh->b_data)->tagLocation);
			udf_release_data(bh);

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

	for (i=0; i<sizeof(UDF_SB_ANCHOR(sb))/sizeof(int); 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 != TID_ANCHOR_VOL_DESC_PTR) && (i ||
					(ident != TID_FILE_ENTRY && ident != TID_EXTENDED_FILE_ENTRY)))
				{
					UDF_SB_ANCHOR(sb)[i] = 0;
				}
			}
		}
		else if (useranchor != 0xFFFFFFFF)
		{
			UDF_SB_ANCHOR(sb)[i] = useranchor;
			useranchor = 0xFFFFFFFF;
			i --;
		}
	}

	return lastblock;
}

static int 
udf_find_fileset(struct super_block *sb, lb_addr *fileset, lb_addr *root)
{
	struct buffer_head *bh = NULL;
	long lastblock;
	Uint16 ident;

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

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

	if (!bh) /* Search backwards through the partitions */
	{
		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 TID_SPACE_BITMAP_DESC:
					{
						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 TID_FILE_SET_DESC:
					{
						*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)) )
	{
		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) = recording;
	}

	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, 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) + UDF_SB_SESSION(sb);

			if (UDF_SB_PARTTYPE(sb,i) == UDF_SPARABLE_MAP15)
				udf_fill_spartable(sb, &UDF_SB_TYPESPAR(sb,i), UDF_SB_PARTLEN(sb,i));

			if (!strcmp(p->partitionContents.ident, PARTITION_CONTENTS_NSR02) ||
				!strcmp(p->partitionContents.ident, PARTITION_CONTENTS_NSR03))
			{
				struct PartitionHeaderDesc *phd;

				phd = (struct PartitionHeaderDesc *)(p->partitionContentsUse);
				if (phd->unallocatedSpaceTable.extLength)
					udf_debug("unallocatedSpaceTable (part %d)\n", i);
				if (phd->unallocatedSpaceBitmap.extLength)
				{
					UDF_SB_PARTMAPS(sb)[i].s_uspace.bitmap =
						le32_to_cpu(phd->unallocatedSpaceBitmap.extPosition);
					UDF_SB_PARTFLAGS(sb,i) |= UDF_PART_FLAG_UNALLOC_BITMAP;
					udf_debug("unallocatedSpaceBitmap (part %d) @ %d\n",
						i, UDF_SB_PARTMAPS(sb)[i].s_uspace.bitmap);
				}
				if (phd->partitionIntegrityTable.extLength)
					udf_debug("partitionIntegrityTable (part %d)\n", i);
				if (phd->freedSpaceTable.extLength)
					udf_debug("freedSpaceTable (part %d)\n", i);
				if (phd->freedSpaceBitmap.extLength)
				{
					UDF_SB_PARTMAPS(sb)[i].s_fspace.bitmap =
						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.bitmap);
				}
			}
			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, lb_addr *fileset)
{
	struct LogicalVolDesc *lvd;
	int i, j, offset;
	Uint8 type;

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

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

	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;
		udf_debug("Partition (%d) type %d\n", i, type);
		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(((Uint16 *)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(((Uint16 *)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)))
			{
				int plen;

				struct SparablePartitionMap *spm = (struct SparablePartitionMap *)&(lvd->partitionMaps[offset]);
				UDF_SB_PARTTYPE(sb,i) = UDF_SPARABLE_MAP15;
				plen = le16_to_cpu(spm->packetLength);
				UDF_SB_TYPESPAR(sb,i).s_spar_pshift = 0;
				while (plen >>= 1)
					UDF_SB_TYPESPAR(sb,i).s_spar_pshift ++;
				for (j=0; j<spm->numSparingTables; j++)
					UDF_SB_TYPESPAR(sb,i).s_spar_loc[j] = le32_to_cpu(spm->locSparingTable[j]);
				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);
		}
	}

	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, extent_ad loc)
{
	struct buffer_head *bh = NULL;
	Uint16 ident;

	while ((bh = udf_read_tagged(sb, loc.extLocation, loc.extLocation, &ident)) &&
		ident == TID_LOGICAL_VOL_INTEGRITY_DESC && loc.extLength > 0)
	{
		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, lb_addr *fileset)
{
	struct buffer_head *bh = NULL;
	struct udf_vds_record vds[VDS_POS_LENGTH];
	struct GenericDesc *gd;
	int done=0;
	int i,j;
	Uint32 vdsn;
	Uint16 ident;

	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 GenericDesc *)bh->b_data;
		vdsn = le32_to_cpu(gd->volDescSeqNum);
		switch (ident)
		{
			case TID_PRIMARY_VOL_DESC: /* 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 TID_VOL_DESC_PTR: /* 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;
				}
				break;
			case TID_IMP_USE_VOL_DESC: /* 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 TID_PARTITION_DESC: /* ISO 13346 3/10.5 */
				if (!vds[VDS_POS_PARTITION_DESC].block)
					vds[VDS_POS_PARTITION_DESC].block = block;
				break;
			case TID_LOGICAL_VOL_DESC: /* 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 TID_UNALLOC_SPACE_DESC: /* 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 TID_TERMINATING_DESC: /* ISO 13346 3/10.9 */
				vds[VDS_POS_TERMINATING_DESC].block = block;
				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 GenericDesc *)bh2->b_data;
					if (ident == TID_PARTITION_DESC)
						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)
	{