inode.c

linux 内核源代码

		strcpy(efe->impIdent.ident, UDF_ID_DEVELOPER);
		efe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
		efe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
		efe->uniqueID = cpu_to_le64(UDF_I_UNIQUE(inode));
		efe->lengthExtendedAttr = cpu_to_le32(UDF_I_LENEATTR(inode));
		efe->lengthAllocDescs = cpu_to_le32(UDF_I_LENALLOC(inode));
		efe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EFE);
		crclen = sizeof(struct extendedFileEntry);
	}
	if (UDF_I_STRAT4096(inode)) {
		fe->icbTag.strategyType = cpu_to_le16(4096);
		fe->icbTag.strategyParameter = cpu_to_le16(1);
		fe->icbTag.numEntries = cpu_to_le16(2);
	} else {
		fe->icbTag.strategyType = cpu_to_le16(4);
		fe->icbTag.numEntries = cpu_to_le16(1);
	}

	if (S_ISDIR(inode->i_mode))
		fe->icbTag.fileType = ICBTAG_FILE_TYPE_DIRECTORY;
	else if (S_ISREG(inode->i_mode))
		fe->icbTag.fileType = ICBTAG_FILE_TYPE_REGULAR;
	else if (S_ISLNK(inode->i_mode))
		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SYMLINK;
	else if (S_ISBLK(inode->i_mode))
		fe->icbTag.fileType = ICBTAG_FILE_TYPE_BLOCK;
	else if (S_ISCHR(inode->i_mode))
		fe->icbTag.fileType = ICBTAG_FILE_TYPE_CHAR;
	else if (S_ISFIFO(inode->i_mode))
		fe->icbTag.fileType = ICBTAG_FILE_TYPE_FIFO;
	else if (S_ISSOCK(inode->i_mode))
		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SOCKET;

	icbflags =	UDF_I_ALLOCTYPE(inode) |
			((inode->i_mode & S_ISUID) ? ICBTAG_FLAG_SETUID : 0) |
			((inode->i_mode & S_ISGID) ? ICBTAG_FLAG_SETGID : 0) |
			((inode->i_mode & S_ISVTX) ? ICBTAG_FLAG_STICKY : 0) |
			(le16_to_cpu(fe->icbTag.flags) &
				~(ICBTAG_FLAG_AD_MASK | ICBTAG_FLAG_SETUID |
				ICBTAG_FLAG_SETGID | ICBTAG_FLAG_STICKY));

	fe->icbTag.flags = cpu_to_le16(icbflags);
	if (UDF_SB_UDFREV(inode->i_sb) >= 0x0200)
		fe->descTag.descVersion = cpu_to_le16(3);
	else
		fe->descTag.descVersion = cpu_to_le16(2);
	fe->descTag.tagSerialNum = cpu_to_le16(UDF_SB_SERIALNUM(inode->i_sb));
	fe->descTag.tagLocation = cpu_to_le32(UDF_I_LOCATION(inode).logicalBlockNum);
	crclen += UDF_I_LENEATTR(inode) + UDF_I_LENALLOC(inode) - sizeof(tag);
	fe->descTag.descCRCLength = cpu_to_le16(crclen);
	fe->descTag.descCRC = cpu_to_le16(udf_crc((char *)fe + sizeof(tag), crclen, 0));

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

	/* write the data blocks */
	mark_buffer_dirty(bh);
	if (do_sync) {
		sync_dirty_buffer(bh);
		if (buffer_req(bh) && !buffer_uptodate(bh)) {
			printk("IO error syncing udf inode [%s:%08lx]\n",
			       inode->i_sb->s_id, inode->i_ino);
			err = -EIO;
		}
	}
	brelse(bh);

	return err;
}

struct inode *udf_iget(struct super_block *sb, kernel_lb_addr ino)
{
	unsigned long block = udf_get_lb_pblock(sb, ino, 0);
	struct inode *inode = iget_locked(sb, block);

	if (!inode)
		return NULL;

	if (inode->i_state & I_NEW) {
		memcpy(&UDF_I_LOCATION(inode), &ino, sizeof(kernel_lb_addr));
		__udf_read_inode(inode);
		unlock_new_inode(inode);
	}

	if (is_bad_inode(inode))
		goto out_iput;

	if (ino.logicalBlockNum >= UDF_SB_PARTLEN(sb, ino.partitionReferenceNum)) {
		udf_debug("block=%d, partition=%d out of range\n",
			  ino.logicalBlockNum, ino.partitionReferenceNum);
		make_bad_inode(inode);
		goto out_iput;
	}

	return inode;

 out_iput:
	iput(inode);
	return NULL;
}

int8_t udf_add_aext(struct inode * inode, struct extent_position * epos,
		    kernel_lb_addr eloc, uint32_t elen, int inc)
{
	int adsize;
	short_ad *sad = NULL;
	long_ad *lad = NULL;
	struct allocExtDesc *aed;
	int8_t etype;
	uint8_t *ptr;

	if (!epos->bh)
		ptr = UDF_I_DATA(inode) + epos->offset - udf_file_entry_alloc_offset(inode) + UDF_I_LENEATTR(inode);
	else
		ptr = epos->bh->b_data + epos->offset;

	if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_SHORT)
		adsize = sizeof(short_ad);
	else if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_LONG)
		adsize = sizeof(long_ad);
	else
		return -1;

	if (epos->offset + (2 * adsize) > inode->i_sb->s_blocksize) {
		char *sptr, *dptr;
		struct buffer_head *nbh;
		int err, loffset;
		kernel_lb_addr obloc = epos->block;

		if (!(epos->block.logicalBlockNum = udf_new_block(inode->i_sb, NULL,
								  obloc.partitionReferenceNum,
								  obloc.logicalBlockNum, &err))) {
			return -1;
		}
		if (!(nbh = udf_tgetblk(inode->i_sb, udf_get_lb_pblock(inode->i_sb,
								       epos->block, 0)))) {
			return -1;
		}
		lock_buffer(nbh);
		memset(nbh->b_data, 0x00, inode->i_sb->s_blocksize);
		set_buffer_uptodate(nbh);
		unlock_buffer(nbh);
		mark_buffer_dirty_inode(nbh, inode);

		aed = (struct allocExtDesc *)(nbh->b_data);
		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT))
			aed->previousAllocExtLocation = cpu_to_le32(obloc.logicalBlockNum);
		if (epos->offset + adsize > inode->i_sb->s_blocksize) {
			loffset = epos->offset;
			aed->lengthAllocDescs = cpu_to_le32(adsize);
			sptr = ptr - adsize;
			dptr = nbh->b_data + sizeof(struct allocExtDesc);
			memcpy(dptr, sptr, adsize);
			epos->offset = sizeof(struct allocExtDesc) + adsize;
		} else {
			loffset = epos->offset + adsize;
			aed->lengthAllocDescs = cpu_to_le32(0);
			sptr = ptr;
			epos->offset = sizeof(struct allocExtDesc);

			if (epos->bh) {
				aed = (struct allocExtDesc *)epos->bh->b_data;
				aed->lengthAllocDescs =
					cpu_to_le32(le32_to_cpu(aed->lengthAllocDescs) + adsize);
			} else {
				UDF_I_LENALLOC(inode) += adsize;
				mark_inode_dirty(inode);
			}
		}
		if (UDF_SB_UDFREV(inode->i_sb) >= 0x0200)
			udf_new_tag(nbh->b_data, TAG_IDENT_AED, 3, 1,
				    epos->block.logicalBlockNum, sizeof(tag));
		else
			udf_new_tag(nbh->b_data, TAG_IDENT_AED, 2, 1,
				    epos->block.logicalBlockNum, sizeof(tag));
		switch (UDF_I_ALLOCTYPE(inode)) {
		case ICBTAG_FLAG_AD_SHORT:
			sad = (short_ad *)sptr;
			sad->extLength = cpu_to_le32(EXT_NEXT_EXTENT_ALLOCDECS |
						     inode->i_sb->s_blocksize);
			sad->extPosition = cpu_to_le32(epos->block.logicalBlockNum);
			break;
		case ICBTAG_FLAG_AD_LONG:
			lad = (long_ad *)sptr;
			lad->extLength = cpu_to_le32(EXT_NEXT_EXTENT_ALLOCDECS |
						     inode->i_sb->s_blocksize);
			lad->extLocation = cpu_to_lelb(epos->block);
			memset(lad->impUse, 0x00, sizeof(lad->impUse));
			break;
		}
		if (epos->bh) {
			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
			    UDF_SB_UDFREV(inode->i_sb) >= 0x0201)
				udf_update_tag(epos->bh->b_data, loffset);
			else
				udf_update_tag(epos->bh->b_data, sizeof(struct allocExtDesc));
			mark_buffer_dirty_inode(epos->bh, inode);
			brelse(epos->bh);
		} else {
			mark_inode_dirty(inode);
		}
		epos->bh = nbh;
	}

	etype = udf_write_aext(inode, epos, eloc, elen, inc);

	if (!epos->bh) {
		UDF_I_LENALLOC(inode) += adsize;
		mark_inode_dirty(inode);
	} else {
		aed = (struct allocExtDesc *)epos->bh->b_data;
		aed->lengthAllocDescs =
			cpu_to_le32(le32_to_cpu(aed->lengthAllocDescs) + adsize);
		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) || UDF_SB_UDFREV(inode->i_sb) >= 0x0201)
			udf_update_tag(epos->bh->b_data, epos->offset + (inc ? 0 : adsize));
		else
			udf_update_tag(epos->bh->b_data, sizeof(struct allocExtDesc));
		mark_buffer_dirty_inode(epos->bh, inode);
	}

	return etype;
}

int8_t udf_write_aext(struct inode * inode, struct extent_position * epos,
		      kernel_lb_addr eloc, uint32_t elen, int inc)
{
	int adsize;
	uint8_t *ptr;
	short_ad *sad;
	long_ad *lad;

	if (!epos->bh)
		ptr = UDF_I_DATA(inode) + epos->offset - udf_file_entry_alloc_offset(inode) + UDF_I_LENEATTR(inode);
	else
		ptr = epos->bh->b_data + epos->offset;

	switch (UDF_I_ALLOCTYPE(inode)) {
	case ICBTAG_FLAG_AD_SHORT:
		sad = (short_ad *)ptr;
		sad->extLength = cpu_to_le32(elen);
		sad->extPosition = cpu_to_le32(eloc.logicalBlockNum);
		adsize = sizeof(short_ad);
		break;
	case ICBTAG_FLAG_AD_LONG:
		lad = (long_ad *)ptr;
		lad->extLength = cpu_to_le32(elen);
		lad->extLocation = cpu_to_lelb(eloc);
		memset(lad->impUse, 0x00, sizeof(lad->impUse));
		adsize = sizeof(long_ad);
		break;
	default:
		return -1;
	}

	if (epos->bh) {
		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
		    UDF_SB_UDFREV(inode->i_sb) >= 0x0201) {
			struct allocExtDesc *aed = (struct allocExtDesc *)epos->bh->b_data;
			udf_update_tag(epos->bh->b_data,
				       le32_to_cpu(aed->lengthAllocDescs) + sizeof(struct allocExtDesc));
		}
		mark_buffer_dirty_inode(epos->bh, inode);
	} else {
		mark_inode_dirty(inode);
	}

	if (inc)
		epos->offset += adsize;

	return (elen >> 30);
}

int8_t udf_next_aext(struct inode * inode, struct extent_position * epos,
		     kernel_lb_addr * eloc, uint32_t * elen, int inc)
{
	int8_t etype;

	while ((etype = udf_current_aext(inode, epos, eloc, elen, inc)) ==
	       (EXT_NEXT_EXTENT_ALLOCDECS >> 30)) {
		epos->block = *eloc;
		epos->offset = sizeof(struct allocExtDesc);
		brelse(epos->bh);
		if (!(epos->bh = udf_tread(inode->i_sb, udf_get_lb_pblock(inode->i_sb, epos->block, 0)))) {
			udf_debug("reading block %d failed!\n",
				  udf_get_lb_pblock(inode->i_sb, epos->block, 0));
			return -1;
		}
	}

	return etype;
}

int8_t udf_current_aext(struct inode * inode, struct extent_position * epos,
			kernel_lb_addr * eloc, uint32_t * elen, int inc)
{
	int alen;
	int8_t etype;
	uint8_t *ptr;
	short_ad *sad;
	long_ad *lad;


	if (!epos->bh) {
		if (!epos->offset)
			epos->offset = udf_file_entry_alloc_offset(inode);
		ptr = UDF_I_DATA(inode) + epos->offset - udf_file_entry_alloc_offset(inode) + UDF_I_LENEATTR(inode);
		alen = udf_file_entry_alloc_offset(inode) + UDF_I_LENALLOC(inode);
	} else {
		if (!epos->offset)
			epos->offset = sizeof(struct allocExtDesc);
		ptr = epos->bh->b_data + epos->offset;
		alen = sizeof(struct allocExtDesc) +
			le32_to_cpu(((struct allocExtDesc *)epos->bh->b_data)->lengthAllocDescs);
	}

	switch (UDF_I_ALLOCTYPE(inode)) {
	case ICBTAG_FLAG_AD_SHORT:
		if (!(sad = udf_get_fileshortad(ptr, alen, &epos->offset, inc)))
			return -1;
		etype = le32_to_cpu(sad->extLength) >> 30;
		eloc->logicalBlockNum = le32_to_cpu(sad->extPosition);
		eloc->partitionReferenceNum = UDF_I_LOCATION(inode).partitionReferenceNum;
		*elen = le32_to_cpu(sad->extLength) & UDF_EXTENT_LENGTH_MASK;
		break;
	case ICBTAG_FLAG_AD_LONG:
		if (!(lad = udf_get_filelongad(ptr, alen, &epos->offset, inc)))
			return -1;
		etype = le32_to_cpu(lad->extLength) >> 30;
		*eloc = lelb_to_cpu(lad->extLocation);
		*elen = le32_to_cpu(lad->extLength) & UDF_EXTENT_LENGTH_MASK;
		break;
	default:
		udf_debug("alloc_type = %d unsupported\n", UDF_I_ALLOCTYPE(inode));
		return -1;
	}

	return etype;
}

static int8_t udf_insert_aext(struct inode *inode, struct extent_position epos,
			      kernel_lb_addr neloc, uint32_t nelen)
{
	kernel_lb_addr oeloc;
	uint32_t oelen;
	int8_t etype;

	if (epos.bh)
		get_bh(epos.bh);

	while ((etype = udf_next_aext(inode, &epos, &oeloc, &oelen, 0)) != -1) {
		udf_write_aext(inode, &epos, neloc, nelen, 1);
		neloc = oeloc;
		nelen = (etype << 30) | oelen;
	}
	udf_add_aext(inode, &epos, neloc, nelen, 1);
	brelse(epos.bh);

	return (nelen >> 30);
}

int8_t udf_delete_aext(struct inode * inode, struct extent_position epos,
		       kernel_lb_addr eloc, uint32_t elen)
{
	struct extent_position oepos;
	int adsize;
	int8_t etype;
	struct allocExtDesc *aed;

	if (epos.bh) {
		get_bh(epos.bh);
		get_bh(epos.bh);
	}

	if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_SHORT)
		adsize = sizeof(short_ad);
	else if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_LONG)
		adsize = sizeof(long_ad);
	else
		adsize = 0;

	oepos = epos;
	if (udf_next_aext(inode, &epos, &eloc, &elen, 1) == -1)
		return -1;

	while ((etype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1) {
		udf_write_aext(inode, &oepos, eloc, (etype << 30) | elen, 1);
		if (oepos.bh != epos.bh) {
			oepos.block = epos.block;
			brelse(oepos.bh);
			get_bh(epos.bh);
			oepos.bh = epos.bh;
			oepos.offset = epos.offset - adsize;
		}
	}
	memset(&eloc, 0x00, sizeof(kernel_lb_addr));
	elen = 0;

	if (epos.bh != oepos.bh) {
		udf_free_blocks(inode->i_sb, inode, epos.block, 0, 1);
		udf_write_aext(inode, &oepos, eloc, elen, 1);
		udf_write_aext(inode, &oepos, eloc, elen, 1);
		if (!oepos.bh) {
			UDF_I_LENALLOC(inode) -= (adsize * 2);
			mark_inode_dirty(inode);
		} else {
			aed = (struct allocExtDesc *)oepos.bh->b_data;
			aed->lengthAllocDescs =
				cpu_to_le32(le32_to_cpu(aed->lengthAllocDescs) - (2 * adsize));
			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
			    UDF_SB_UDFREV(inode->i_sb) >= 0x0201)
				udf_update_tag(oepos.bh->b_data, oepos.offset - (2 * adsize));
			else
				udf_update_tag(oepos.bh->b_data, sizeof(struct allocExtDesc));
			mark_buffer_dirty_inode(oepos.bh, inode);
		}
	} else {
		udf_write_aext(inode, &oepos, eloc, elen, 1);
		if (!oepos.bh) {
			UDF_I_LENALLOC(inode) -= adsize;
			mark_inode_dirty(inode);
		} else {
			aed = (struct allocExtDesc *)oepos.bh->b_data;
			aed->lengthAllocDescs =
				cpu_to_le32(le32_to_cpu(aed->lengthAllocDescs) - adsize);
			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
			    UDF_SB_UDFREV(inode->i_sb) >= 0x0201)
				udf_update_tag(oepos.bh->b_data, epos.offset - adsize);
			else
				udf_update_tag(oepos.bh->b_data, sizeof(struct allocExtDesc));
			mark_buffer_dirty_inode(oepos.bh, inode);
		}
	}

	brelse(epos.bh);
	brelse(oepos.bh);

	return (elen >> 30);
}

int8_t inode_bmap(struct inode * inode, sector_t block,
		  struct extent_position * pos, kernel_lb_addr * eloc,
		  uint32_t * elen, sector_t * offset)
{
	loff_t lbcount = 0, bcount =
	    (loff_t) block << inode->i_sb->s_blocksize_bits;
	int8_t etype;

	if (block < 0) {
		printk(KERN_ERR "udf: inode_bmap: block < 0\n");
		return -1;
	}

	pos->offset = 0;
	pos->block = UDF_I_LOCATION(inode);
	pos->bh = NULL;
	*elen = 0;

	do {
		if ((etype = udf_next_aext(inode, pos, eloc, elen, 1)) == -1) {
			*offset = (bcount - lbcount) >> inode->i_sb->s_blocksize_bits;
			UDF_I_LENEXTENTS(inode) = lbcount;
			return -1;
		}
		lbcount += *elen;
	} while (lbcount <= bcount);

	*offset = (bcount + *elen - lbcount) >> inode->i_sb->s_blocksize_bits;

	return etype;
}

long udf_block_map(struct inode *inode, sector_t block)
{
	kernel_lb_addr eloc;
	uint32_t elen;
	sector_t offset;
	struct extent_position epos = {};
	int ret;

	lock_kernel();

	if (inode_bmap(inode, block, &epos, &eloc, &elen, &offset) == (EXT_RECORDED_ALLOCATED >> 30))
		ret = udf_get_lb_pblock(inode->i_sb, eloc, offset);
	else
		ret = 0;

	unlock_kernel();
	brelse(epos.bh);

	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_VARCONV))
		return udf_fixed_to_variable(ret);
	else
		return ret;
}