static struct fileIdentDesc *udf_add_entry(struct inode *dir,
					   struct dentry *dentry,
					   struct udf_fileident_bh *fibh,
					   struct fileIdentDesc *cfi, int *err)
{
	struct super_block *sb = dir->i_sb;
	struct fileIdentDesc *fi = NULL;
	unsigned char *name = NULL;
	int namelen;
	loff_t f_pos;
	loff_t size = udf_ext0_offset(dir) + dir->i_size;
	int nfidlen;
	uint8_t lfi;
	uint16_t liu;
	int block;
	struct kernel_lb_addr eloc;
	uint32_t elen = 0;
	sector_t offset;
	struct extent_position epos = {};
	struct udf_inode_info *dinfo;

	fibh->sbh = fibh->ebh = NULL;
	name = kmalloc(UDF_NAME_LEN, GFP_NOFS);
	if (!name) {
		*err = -ENOMEM;
		goto out_err;
	}

	if (dentry) {
		if (!dentry->d_name.len) {
			*err = -EINVAL;
			goto out_err;
		}
		namelen = udf_put_filename(sb, dentry->d_name.name, name,
						 dentry->d_name.len);
		if (!namelen) {
			*err = -ENAMETOOLONG;
			goto out_err;
		}
	} else {
		namelen = 0;
	}

	nfidlen = (sizeof(struct fileIdentDesc) + namelen + 3) & ~3;

	f_pos = udf_ext0_offset(dir);

	fibh->soffset = fibh->eoffset = f_pos & (dir->i_sb->s_blocksize - 1);
	dinfo = UDF_I(dir);
	if (dinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
		if (inode_bmap(dir, f_pos >> dir->i_sb->s_blocksize_bits, &epos,
		    &eloc, &elen, &offset) != (EXT_RECORDED_ALLOCATED >> 30)) {
			block = udf_get_lb_pblock(dir->i_sb,
					&dinfo->i_location, 0);
			fibh->soffset = fibh->eoffset = sb->s_blocksize;
			goto add;
		}
		block = udf_get_lb_pblock(dir->i_sb, &eloc, offset);
		if ((++offset << dir->i_sb->s_blocksize_bits) < elen) {
			if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
				epos.offset -= sizeof(struct short_ad);
			else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
				epos.offset -= sizeof(struct long_ad);
		} else
			offset = 0;

		fibh->sbh = fibh->ebh = udf_tread(dir->i_sb, block);
		if (!fibh->sbh) {
			*err = -EIO;
			goto out_err;
		}

		block = dinfo->i_location.logicalBlockNum;
	}

	while (f_pos < size) {
		fi = udf_fileident_read(dir, &f_pos, fibh, cfi, &epos, &eloc,
					&elen, &offset);

		if (!fi) {
			*err = -EIO;
			goto out_err;
		}

		liu = le16_to_cpu(cfi->lengthOfImpUse);
		lfi = cfi->lengthFileIdent;

		if ((cfi->fileCharacteristics & FID_FILE_CHAR_DELETED) != 0) {
			if (((sizeof(struct fileIdentDesc) +
					liu + lfi + 3) & ~3) == nfidlen) {
				cfi->descTag.tagSerialNum = cpu_to_le16(1);
				cfi->fileVersionNum = cpu_to_le16(1);
				cfi->fileCharacteristics = 0;
				cfi->lengthFileIdent = namelen;
				cfi->lengthOfImpUse = cpu_to_le16(0);
				if (!udf_write_fi(dir, cfi, fi, fibh, NULL,
						  name))
					goto out_ok;
				else {
					*err = -EIO;
					goto out_err;
				}
			}
		}
	}

add:
	f_pos += nfidlen;

	if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB &&
	    sb->s_blocksize - fibh->eoffset < nfidlen) {
		brelse(epos.bh);
		epos.bh = NULL;
		fibh->soffset -= udf_ext0_offset(dir);
		fibh->eoffset -= udf_ext0_offset(dir);
		f_pos -= udf_ext0_offset(dir);
		if (fibh->sbh != fibh->ebh)
			brelse(fibh->ebh);
		brelse(fibh->sbh);
		fibh->sbh = fibh->ebh =
				udf_expand_dir_adinicb(dir, &block, err);
		if (!fibh->sbh)
			goto out_err;
		epos.block = dinfo->i_location;
		epos.offset = udf_file_entry_alloc_offset(dir);
		/* Load extent udf_expand_dir_adinicb() has created */
		udf_current_aext(dir, &epos, &eloc, &elen, 1);
	}

	/* Entry fits into current block? */
	if (sb->s_blocksize - fibh->eoffset >= nfidlen) {
		fibh->soffset = fibh->eoffset;
		fibh->eoffset += nfidlen;
		if (fibh->sbh != fibh->ebh) {
			brelse(fibh->sbh);
			fibh->sbh = fibh->ebh;
		}

		if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
			block = dinfo->i_location.logicalBlockNum;
			fi = (struct fileIdentDesc *)
					(dinfo->i_ext.i_data +
					 fibh->soffset -
					 udf_ext0_offset(dir) +
					 dinfo->i_lenEAttr);
		} else {
			block = eloc.logicalBlockNum +
					((elen - 1) >>
						dir->i_sb->s_blocksize_bits);
			fi = (struct fileIdentDesc *)
				(fibh->sbh->b_data + fibh->soffset);
		}
	} else {
		/* Round up last extent in the file */
		elen = (elen + sb->s_blocksize - 1) & ~(sb->s_blocksize - 1);
		if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
			epos.offset -= sizeof(struct short_ad);
		else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
			epos.offset -= sizeof(struct long_ad);
		udf_write_aext(dir, &epos, &eloc, elen, 1);
		dinfo->i_lenExtents = (dinfo->i_lenExtents + sb->s_blocksize
					- 1) & ~(sb->s_blocksize - 1);

		fibh->soffset = fibh->eoffset - sb->s_blocksize;
		fibh->eoffset += nfidlen - sb->s_blocksize;
		if (fibh->sbh != fibh->ebh) {
			brelse(fibh->sbh);
			fibh->sbh = fibh->ebh;
		}

		block = eloc.logicalBlockNum + ((elen - 1) >>
						dir->i_sb->s_blocksize_bits);
		fibh->ebh = udf_bread(dir,
				f_pos >> dir->i_sb->s_blocksize_bits, 1, err);
		if (!fibh->ebh)
			goto out_err;
		/* Extents could have been merged, invalidate our position */
		brelse(epos.bh);
		epos.bh = NULL;
		epos.block = dinfo->i_location;
		epos.offset = udf_file_entry_alloc_offset(dir);

		if (!fibh->soffset) {
			/* Find the freshly allocated block */
			while (udf_next_aext(dir, &epos, &eloc, &elen, 1) ==
				(EXT_RECORDED_ALLOCATED >> 30))
				;
			block = eloc.logicalBlockNum + ((elen - 1) >>
					dir->i_sb->s_blocksize_bits);
			brelse(fibh->sbh);
			fibh->sbh = fibh->ebh;
			fi = (struct fileIdentDesc *)(fibh->sbh->b_data);
		} else {
			fi = (struct fileIdentDesc *)
				(fibh->sbh->b_data + sb->s_blocksize +
					fibh->soffset);
		}
	}

	memset(cfi, 0, sizeof(struct fileIdentDesc));
	if (UDF_SB(sb)->s_udfrev >= 0x0200)
		udf_new_tag((char *)cfi, TAG_IDENT_FID, 3, 1, block,
			    sizeof(struct tag));
	else
		udf_new_tag((char *)cfi, TAG_IDENT_FID, 2, 1, block,
			    sizeof(struct tag));
	cfi->fileVersionNum = cpu_to_le16(1);
	cfi->lengthFileIdent = namelen;
	cfi->lengthOfImpUse = cpu_to_le16(0);
	if (!udf_write_fi(dir, cfi, fi, fibh, NULL, name)) {
		dir->i_size += nfidlen;
		if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
			dinfo->i_lenAlloc += nfidlen;
		else {
			/* Find the last extent and truncate it to proper size */
			while (udf_next_aext(dir, &epos, &eloc, &elen, 1) ==
				(EXT_RECORDED_ALLOCATED >> 30))
				;
			elen -= dinfo->i_lenExtents - dir->i_size;
			if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
				epos.offset -= sizeof(struct short_ad);
			else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
				epos.offset -= sizeof(struct long_ad);
			udf_write_aext(dir, &epos, &eloc, elen, 1);
			dinfo->i_lenExtents = dir->i_size;
		}

		mark_inode_dirty(dir);
		goto out_ok;
	} else {
		*err = -EIO;
		goto out_err;
	}

out_err:
	fi = NULL;
	if (fibh->sbh != fibh->ebh)
		brelse(fibh->ebh);
	brelse(fibh->sbh);
out_ok:
	brelse(epos.bh);
	kfree(name);
	return fi;
}