text: /*
   * inode.c
   *
   * PURPOSE
   *  Inode handling routines for the OSTA-UDF(tm) filesystem.
   *
   * 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) 1999-2000 Stelias Computing Inc
   *
   * HISTORY
   *
   *  10/04/98 dgb  Added rudimentary directory functions
   *  10/07/98      Fully working udf_block_map! It works!
   *  11/25/98      bmap altered to better support extents
   *  12/06/98 blf  partition support in udf_iget, udf_block_map
   *                and udf_read_inode
   *  12/12/98      rewrote udf_block_map to handle next extents and descs across
   *                block boundaries (which is not actually allowed)
   *  12/20/98      added support for strategy 4096
   *  03/07/99      rewrote udf_block_map (again)
   *                New funcs, inode_bmap, udf_next_aext
   *  04/19/99      Support for writing device EA's for major/minor #
   */
  
  #include "udfdecl.h"
  #include <linux/mm.h>
  #include <linux/module.h>
  #include <linux/pagemap.h>
  #include <linux/buffer_head.h>
  #include <linux/writeback.h>
  #include <linux/slab.h>
  #include <linux/crc-itu-t.h>
  #include <linux/mpage.h>
  #include <linux/aio.h>
  
  #include "udf_i.h"
  #include "udf_sb.h"
  
  MODULE_AUTHOR("Ben Fennema");
  MODULE_DESCRIPTION("Universal Disk Format Filesystem");
  MODULE_LICENSE("GPL");
  
  #define EXTENT_MERGE_SIZE 5
  
  static umode_t udf_convert_permissions(struct fileEntry *);
  static int udf_update_inode(struct inode *, int);
  static void udf_fill_inode(struct inode *, struct buffer_head *);
  static int udf_sync_inode(struct inode *inode);
  static int udf_alloc_i_data(struct inode *inode, size_t size);
  static sector_t inode_getblk(struct inode *, sector_t, int *, int *);
  static int8_t udf_insert_aext(struct inode *, struct extent_position,
  			      struct kernel_lb_addr, uint32_t);
  static void udf_split_extents(struct inode *, int *, int, int,
  			      struct kernel_long_ad[EXTENT_MERGE_SIZE], int *);
  static void udf_prealloc_extents(struct inode *, int, int,
  				 struct kernel_long_ad[EXTENT_MERGE_SIZE], int *);
  static void udf_merge_extents(struct inode *,
  			      struct kernel_long_ad[EXTENT_MERGE_SIZE], int *);
  static void udf_update_extents(struct inode *,
  			       struct kernel_long_ad[EXTENT_MERGE_SIZE], int, int,
  			       struct extent_position *);
  static int udf_get_block(struct inode *, sector_t, struct buffer_head *, int);
  
  static void __udf_clear_extent_cache(struct inode *inode)
  {
  	struct udf_inode_info *iinfo = UDF_I(inode);
  
  	if (iinfo->cached_extent.lstart != -1) {
  		brelse(iinfo->cached_extent.epos.bh);
  		iinfo->cached_extent.lstart = -1;
  	}
  }
  
  /* Invalidate extent cache */
  static void udf_clear_extent_cache(struct inode *inode)
  {
  	struct udf_inode_info *iinfo = UDF_I(inode);
  
  	spin_lock(&iinfo->i_extent_cache_lock);
  	__udf_clear_extent_cache(inode);
  	spin_unlock(&iinfo->i_extent_cache_lock);
  }
  
  /* Return contents of extent cache */
  static int udf_read_extent_cache(struct inode *inode, loff_t bcount,
  				 loff_t *lbcount, struct extent_position *pos)
  {
  	struct udf_inode_info *iinfo = UDF_I(inode);
  	int ret = 0;
  
  	spin_lock(&iinfo->i_extent_cache_lock);
  	if ((iinfo->cached_extent.lstart <= bcount) &&
  	    (iinfo->cached_extent.lstart != -1)) {
  		/* Cache hit */
  		*lbcount = iinfo->cached_extent.lstart;
  		memcpy(pos, &iinfo->cached_extent.epos,
  		       sizeof(struct extent_position));
  		if (pos->bh)
  			get_bh(pos->bh);
  		ret = 1;
  	}
  	spin_unlock(&iinfo->i_extent_cache_lock);
  	return ret;
  }
  
  /* Add extent to extent cache */
  static void udf_update_extent_cache(struct inode *inode, loff_t estart,
  				    struct extent_position *pos, int next_epos)
  {
  	struct udf_inode_info *iinfo = UDF_I(inode);
  
  	spin_lock(&iinfo->i_extent_cache_lock);
  	/* Invalidate previously cached extent */
  	__udf_clear_extent_cache(inode);
  	if (pos->bh)
  		get_bh(pos->bh);
  	memcpy(&iinfo->cached_extent.epos, pos,
  	       sizeof(struct extent_position));
  	iinfo->cached_extent.lstart = estart;
  	if (next_epos)
  		switch (iinfo->i_alloc_type) {
  		case ICBTAG_FLAG_AD_SHORT:
  			iinfo->cached_extent.epos.offset -=
  			sizeof(struct short_ad);
  			break;
  		case ICBTAG_FLAG_AD_LONG:
  			iinfo->cached_extent.epos.offset -=
  			sizeof(struct long_ad);
  		}
  	spin_unlock(&iinfo->i_extent_cache_lock);
  }
  
  void udf_evict_inode(struct inode *inode)
  {
  	struct udf_inode_info *iinfo = UDF_I(inode);
  	int want_delete = 0;
  
  	if (!inode->i_nlink && !is_bad_inode(inode)) {
  		want_delete = 1;
  		udf_setsize(inode, 0);
  		udf_update_inode(inode, IS_SYNC(inode));
  	} else
  		truncate_inode_pages(&inode->i_data, 0);
  	invalidate_inode_buffers(inode);
  	clear_inode(inode);
  	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB &&
  	    inode->i_size != iinfo->i_lenExtents) {
  		udf_warn(inode->i_sb, "Inode %lu (mode %o) has inode size %llu different from extent length %llu. Filesystem need not be standards compliant.\n",
  			 inode->i_ino, inode->i_mode,
  			 (unsigned long long)inode->i_size,
  			 (unsigned long long)iinfo->i_lenExtents);
  	}
  	kfree(iinfo->i_ext.i_data);
  	iinfo->i_ext.i_data = NULL;
  	udf_clear_extent_cache(inode);
  	if (want_delete) {
  		udf_free_inode(inode);
  	}
  }
  
  static void udf_write_failed(struct address_space *mapping, loff_t to)
  {
  	struct inode *inode = mapping->host;
  	struct udf_inode_info *iinfo = UDF_I(inode);
  	loff_t isize = inode->i_size;
  
  	if (to > isize) {
  		truncate_pagecache(inode, isize);
  		if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
  			down_write(&iinfo->i_data_sem);
  			udf_clear_extent_cache(inode);
  			udf_truncate_extents(inode);
  			up_write(&iinfo->i_data_sem);
  		}
  	}
  }
  
  static int udf_writepage(struct page *page, struct writeback_control *wbc)
  {
  	return block_write_full_page(page, udf_get_block, wbc);
  }
  
  static int udf_writepages(struct address_space *mapping,
  			struct writeback_control *wbc)
  {
  	return mpage_writepages(mapping, wbc, udf_get_block);
  }
  
  static int udf_readpage(struct file *file, struct page *page)
  {
  	return mpage_readpage(page, udf_get_block);
  }
  
  static int udf_readpages(struct file *file, struct address_space *mapping,
  			struct list_head *pages, unsigned nr_pages)
  {
  	return mpage_readpages(mapping, pages, nr_pages, udf_get_block);
  }
  
  static int udf_write_begin(struct file *file, struct address_space *mapping,
  			loff_t pos, unsigned len, unsigned flags,
  			struct page **pagep, void **fsdata)
  {
  	int ret;
  
  	ret = block_write_begin(mapping, pos, len, flags, pagep, udf_get_block);
  	if (unlikely(ret))
  		udf_write_failed(mapping, pos + len);
  	return ret;
  }
  
  static ssize_t udf_direct_IO(int rw, struct kiocb *iocb,
  			     const struct iovec *iov,
  			     loff_t offset, unsigned long nr_segs)
  {
  	struct file *file = iocb->ki_filp;
  	struct address_space *mapping = file->f_mapping;
  	struct inode *inode = mapping->host;
  	ssize_t ret;
  
  	ret = blockdev_direct_IO(rw, iocb, inode, iov, offset, nr_segs,
  				  udf_get_block);
  	if (unlikely(ret < 0 && (rw & WRITE)))
  		udf_write_failed(mapping, offset + iov_length(iov, nr_segs));
  	return ret;
  }
  
  static sector_t udf_bmap(struct address_space *mapping, sector_t block)
  {
  	return generic_block_bmap(mapping, block, udf_get_block);
  }
  
  const struct address_space_operations udf_aops = {
  	.readpage	= udf_readpage,
  	.readpages	= udf_readpages,
  	.writepage	= udf_writepage,
  	.writepages	= udf_writepages,
  	.write_begin	= udf_write_begin,
  	.write_end	= generic_write_end,
  	.direct_IO	= udf_direct_IO,
  	.bmap		= udf_bmap,
  };
  
  /*
   * Expand file stored in ICB to a normal one-block-file
   *
   * This function requires i_data_sem for writing and releases it.
   * This function requires i_mutex held
   */
  int udf_expand_file_adinicb(struct inode *inode)
  {
  	struct page *page;
  	char *kaddr;
  	struct udf_inode_info *iinfo = UDF_I(inode);
  	int err;
  	struct writeback_control udf_wbc = {
  		.sync_mode = WB_SYNC_NONE,
  		.nr_to_write = 1,
  	};
  
  	if (!iinfo->i_lenAlloc) {
  		if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
  			iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
  		else
  			iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
  		/* from now on we have normal address_space methods */
  		inode->i_data.a_ops = &udf_aops;
  		up_write(&iinfo->i_data_sem);
  		mark_inode_dirty(inode);
  		return 0;
  	}
  	/*
  	 * Release i_data_sem so that we can lock a page - page lock ranks
  	 * above i_data_sem. i_mutex still protects us against file changes.
  	 */
  	up_write(&iinfo->i_data_sem);
  
  	page = find_or_create_page(inode->i_mapping, 0, GFP_NOFS);
  	if (!page)
  		return -ENOMEM;
  
  	if (!PageUptodate(page)) {
  		kaddr = kmap(page);
  		memset(kaddr + iinfo->i_lenAlloc, 0x00,
  		       PAGE_CACHE_SIZE - iinfo->i_lenAlloc);
  		memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr,
  			iinfo->i_lenAlloc);
  		flush_dcache_page(page);
  		SetPageUptodate(page);
  		kunmap(page);
  	}
  	down_write(&iinfo->i_data_sem);
  	memset(iinfo->i_ext.i_data + iinfo->i_lenEAttr, 0x00,
  	       iinfo->i_lenAlloc);
  	iinfo->i_lenAlloc = 0;
  	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
  		iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
  	else
  		iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
  	/* from now on we have normal address_space methods */
  	inode->i_data.a_ops = &udf_aops;
  	up_write(&iinfo->i_data_sem);
  	err = inode->i_data.a_ops->writepage(page, &udf_wbc);
  	if (err) {
  		/* Restore everything back so that we don't lose data... */
  		lock_page(page);
  		kaddr = kmap(page);
  		down_write(&iinfo->i_data_sem);
  		memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr, kaddr,
  		       inode->i_size);
  		kunmap(page);
  		unlock_page(page);
  		iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
  		inode->i_data.a_ops = &udf_adinicb_aops;
  		up_write(&iinfo->i_data_sem);
  	}
  	page_cache_release(page);
  	mark_inode_dirty(inode);
  
  	return err;
  }
  
  struct buffer_head *udf_expand_dir_adinicb(struct inode *inode, int *block,
  					   int *err)
  {
  	int newblock;
  	struct buffer_head *dbh = NULL;
  	struct kernel_lb_addr eloc;
  	uint8_t alloctype;
  	struct extent_position epos;
  
  	struct udf_fileident_bh sfibh, dfibh;
  	loff_t f_pos = udf_ext0_offset(inode);
  	int size = udf_ext0_offset(inode) + inode->i_size;
  	struct fileIdentDesc cfi, *sfi, *dfi;
  	struct udf_inode_info *iinfo = UDF_I(inode);
  
  	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
  		alloctype = ICBTAG_FLAG_AD_SHORT;
  	else
  		alloctype = ICBTAG_FLAG_AD_LONG;
  
  	if (!inode->i_size) {
  		iinfo->i_alloc_type = alloctype;
  		mark_inode_dirty(inode);
  		return NULL;
  	}
  
  	/* alloc block, and copy data to it */
  	*block = udf_new_block(inode->i_sb, inode,
  			       iinfo->i_location.partitionReferenceNum,
  			       iinfo->i_location.logicalBlockNum, err);
  	if (!(*block))
  		return NULL;
  	newblock = udf_get_pblock(inode->i_sb, *block,
  				  iinfo->i_location.partitionReferenceNum,
  				0);
  	if (!newblock)
  		return NULL;
  	dbh = udf_tgetblk(inode->i_sb, newblock);
  	if (!dbh)
  		return NULL;
  	lock_buffer(dbh);
  	memset(dbh->b_data, 0x00, inode->i_sb->s_blocksize);
  	set_buffer_uptodate(dbh);
  	unlock_buffer(dbh);
  	mark_buffer_dirty_inode(dbh, inode);
  
  	sfibh.soffset = sfibh.eoffset =
  			f_pos & (inode->i_sb->s_blocksize - 1);
  	sfibh.sbh = sfibh.ebh = NULL;
  	dfibh.soffset = dfibh.eoffset = 0;
  	dfibh.sbh = dfibh.ebh = dbh;
  	while (f_pos < size) {
  		iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
  		sfi = udf_fileident_read(inode, &f_pos, &sfibh, &cfi, NULL,
  					 NULL, NULL, NULL);
  		if (!sfi) {
  			brelse(dbh);
  			return NULL;
  		}
  		iinfo->i_alloc_type = alloctype;
  		sfi->descTag.tagLocation = cpu_to_le32(*block);
  		dfibh.soffset = dfibh.eoffset;
  		dfibh.eoffset += (sfibh.eoffset - sfibh.soffset);
  		dfi = (struct fileIdentDesc *)(dbh->b_data + dfibh.soffset);
  		if (udf_write_fi(inode, sfi, dfi, &dfibh, sfi->impUse,
  				 sfi->fileIdent +
  					le16_to_cpu(sfi->lengthOfImpUse))) {
  			iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
  			brelse(dbh);
  			return NULL;
  		}
  	}
  	mark_buffer_dirty_inode(dbh, inode);
  
  	memset(iinfo->i_ext.i_data + iinfo->i_lenEAttr, 0,
  		iinfo->i_lenAlloc);
  	iinfo->i_lenAlloc = 0;
  	eloc.logicalBlockNum = *block;
  	eloc.partitionReferenceNum =
  				iinfo->i_location.partitionReferenceNum;
  	iinfo->i_lenExtents = inode->i_size;
  	epos.bh = NULL;
  	epos.block = iinfo->i_location;
  	epos.offset = udf_file_entry_alloc_offset(inode);
  	udf_add_aext(inode, &epos, &eloc, inode->i_size, 0);
  	/* UniqueID stuff */
  
  	brelse(epos.bh);
  	mark_inode_dirty(inode);
  	return dbh;
  }
  
  static int udf_get_block(struct inode *inode, sector_t block,
  			 struct buffer_head *bh_result, int create)
  {
  	int err, new;
  	sector_t phys = 0;
  	struct udf_inode_info *iinfo;
  
  	if (!create) {
  		phys = udf_block_map(inode, block);
  		if (phys)
  			map_bh(bh_result, inode->i_sb, phys);
  		return 0;
  	}
  
  	err = -EIO;
  	new = 0;
  	iinfo = UDF_I(inode);
  
  	down_write(&iinfo->i_data_sem);
  	if (block == iinfo->i_next_alloc_block + 1) {
  		iinfo->i_next_alloc_block++;
  		iinfo->i_next_alloc_goal++;
  	}
  
  	udf_clear_extent_cache(inode);
  	phys = inode_getblk(inode, block, &err, &new);
  	if (!phys)
  		goto abort;
  
  	if (new)
  		set_buffer_new(bh_result);
  	map_bh(bh_result, inode->i_sb, phys);
  
  abort:
  	up_write(&iinfo->i_data_sem);
  	return err;
  }
  
  static struct buffer_head *udf_getblk(struct inode *inode, long block,
  				      int create, int *err)
  {
  	struct buffer_head *bh;
  	struct buffer_head dummy;
  
  	dummy.b_state = 0;
  	dummy.b_blocknr = -1000;
  	*err = udf_get_block(inode, block, &dummy, create);
  	if (!*err && buffer_mapped(&dummy)) {
  		bh = sb_getblk(inode->i_sb, dummy.b_blocknr);
  		if (buffer_new(&dummy)) {
  			lock_buffer(bh);
  			memset(bh->b_data, 0x00, inode->i_sb->s_blocksize);
  			set_buffer_uptodate(bh);
  			unlock_buffer(bh);
  			mark_buffer_dirty_inode(bh, inode);
  		}
  		return bh;
  	}
  
  	return NULL;
  }
  
  /* Extend the file by 'blocks' blocks, return the number of extents added */
  static int udf_do_extend_file(struct inode *inode,
  			      struct extent_position *last_pos,
  			      struct kernel_long_ad *last_ext,
  			      sector_t blocks)
  {
  	sector_t add;
  	int count = 0, fake = !(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
  	struct super_block *sb = inode->i_sb;
  	struct kernel_lb_addr prealloc_loc = {};
  	int prealloc_len = 0;
  	struct udf_inode_info *iinfo;
  	int err;
  
  	/* The previous extent is fake and we should not extend by anything
  	 * - there's nothing to do... */
  	if (!blocks && fake)
  		return 0;
  
  	iinfo = UDF_I(inode);
  	/* Round the last extent up to a multiple of block size */
  	if (last_ext->extLength & (sb->s_blocksize - 1)) {
  		last_ext->extLength =
  			(last_ext->extLength & UDF_EXTENT_FLAG_MASK) |
  			(((last_ext->extLength & UDF_EXTENT_LENGTH_MASK) +
  			  sb->s_blocksize - 1) & ~(sb->s_blocksize - 1));
  		iinfo->i_lenExtents =
  			(iinfo->i_lenExtents + sb->s_blocksize - 1) &
  			~(sb->s_blocksize - 1);
  	}
  
  	/* Last extent are just preallocated blocks? */
  	if ((last_ext->extLength & UDF_EXTENT_FLAG_MASK) ==
  						EXT_NOT_RECORDED_ALLOCATED) {
  		/* Save the extent so that we can reattach it to the end */
  		prealloc_loc = last_ext->extLocation;
  		prealloc_len = last_ext->extLength;
  		/* Mark the extent as a hole */
  		last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
  			(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
  		last_ext->extLocation.logicalBlockNum = 0;
  		last_ext->extLocation.partitionReferenceNum = 0;
  	}
  
  	/* Can we merge with the previous extent? */
  	if ((last_ext->extLength & UDF_EXTENT_FLAG_MASK) ==
  					EXT_NOT_RECORDED_NOT_ALLOCATED) {
  		add = ((1 << 30) - sb->s_blocksize -
  			(last_ext->extLength & UDF_EXTENT_LENGTH_MASK)) >>
  			sb->s_blocksize_bits;
  		if (add > blocks)
  			add = blocks;
  		blocks -= add;
  		last_ext->extLength += add << sb->s_blocksize_bits;
  	}
  
  	if (fake) {
  		udf_add_aext(inode, last_pos, &last_ext->extLocation,
  			     last_ext->extLength, 1);
  		count++;
  	} else
  		udf_write_aext(inode, last_pos, &last_ext->extLocation,
  				last_ext->extLength, 1);
  
  	/* Managed to do everything necessary? */
  	if (!blocks)
  		goto out;
  
  	/* All further extents will be NOT_RECORDED_NOT_ALLOCATED */
  	last_ext->extLocation.logicalBlockNum = 0;
  	last_ext->extLocation.partitionReferenceNum = 0;
  	add = (1 << (30-sb->s_blocksize_bits)) - 1;
  	last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
  				(add << sb->s_blocksize_bits);
  
  	/* Create enough extents to cover the whole hole */
  	while (blocks > add) {
  		blocks -= add;
  		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
  				   last_ext->extLength, 1);
  		if (err)
  			return err;
  		count++;
  	}
  	if (blocks) {
  		last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
  			(blocks << sb->s_blocksize_bits);
  		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
  				   last_ext->extLength, 1);
  		if (err)
  			return err;
  		count++;
  	}
  
  out:
  	/* Do we have some preallocated blocks saved? */
  	if (prealloc_len) {
  		err = udf_add_aext(inode, last_pos, &prealloc_loc,
  				   prealloc_len, 1);
  		if (err)
  			return err;
  		last_ext->extLocation = prealloc_loc;
  		last_ext->extLength = prealloc_len;
  		count++;
  	}
  
  	/* last_pos should point to the last written extent... */
  	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
  		last_pos->offset -= sizeof(struct short_ad);
  	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
  		last_pos->offset -= sizeof(struct long_ad);
  	else
  		return -EIO;
  
  	return count;
  }
  
  static int udf_extend_file(struct inode *inode, loff_t newsize)
  {
  
  	struct extent_position epos;
  	struct kernel_lb_addr eloc;
  	uint32_t elen;
  	int8_t etype;
  	struct super_block *sb = inode->i_sb;
  	sector_t first_block = newsize >> sb->s_blocksize_bits, offset;
  	int adsize;
  	struct udf_inode_info *iinfo = UDF_I(inode);
  	struct kernel_long_ad extent;
  	int err;
  
  	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
  		adsize = sizeof(struct short_ad);
  	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
  		adsize = sizeof(struct long_ad);
  	else
  		BUG();
  
  	etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset);
  
  	/* File has extent covering the new size (could happen when extending
  	 * inside a block)? */
  	if (etype != -1)
  		return 0;
  	if (newsize & (sb->s_blocksize - 1))
  		offset++;
  	/* Extended file just to the boundary of the last file block? */
  	if (offset == 0)
  		return 0;
  
  	/* Truncate is extending the file by 'offset' blocks */
  	if ((!epos.bh && epos.offset == udf_file_entry_alloc_offset(inode)) ||
  	    (epos.bh && epos.offset == sizeof(struct allocExtDesc))) {
  		/* File has no extents at all or has empty last
  		 * indirect extent! Create a fake extent... */
  		extent.extLocation.logicalBlockNum = 0;
  		extent.extLocation.partitionReferenceNum = 0;
  		extent.extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
  	} else {
  		epos.offset -= adsize;
  		etype = udf_next_aext(inode, &epos, &extent.extLocation,
  				      &extent.extLength, 0);
  		extent.extLength |= etype << 30;
  	}
  	err = udf_do_extend_file(inode, &epos, &extent, offset);
  	if (err < 0)
  		goto out;
  	err = 0;
  	iinfo->i_lenExtents = newsize;
  out:
  	brelse(epos.bh);
  	return err;
  }
  
  static sector_t inode_getblk(struct inode *inode, sector_t block,
  			     int *err, int *new)
  {
  	struct kernel_long_ad laarr[EXTENT_MERGE_SIZE];
  	struct extent_position prev_epos, cur_epos, next_epos;
  	int count = 0, startnum = 0, endnum = 0;
  	uint32_t elen = 0, tmpelen;
  	struct kernel_lb_addr eloc, tmpeloc;
  	int c = 1;
  	loff_t lbcount = 0, b_off = 0;
  	uint32_t newblocknum, newblock;
  	sector_t offset = 0;
  	int8_t etype;
  	struct udf_inode_info *iinfo = UDF_I(inode);
  	int goal = 0, pgoal = iinfo->i_location.logicalBlockNum;
  	int lastblock = 0;
  	bool isBeyondEOF;
  
  	*err = 0;
  	*new = 0;
  	prev_epos.offset = udf_file_entry_alloc_offset(inode);
  	prev_epos.block = iinfo->i_location;
  	prev_epos.bh = NULL;
  	cur_epos = next_epos = prev_epos;
  	b_off = (loff_t)block << inode->i_sb->s_blocksize_bits;
  
  	/* find the extent which contains the block we are looking for.
  	   alternate between laarr[0] and laarr[1] for locations of the
  	   current extent, and the previous extent */
  	do {
  		if (prev_epos.bh != cur_epos.bh) {
  			brelse(prev_epos.bh);
  			get_bh(cur_epos.bh);
  			prev_epos.bh = cur_epos.bh;
  		}
  		if (cur_epos.bh != next_epos.bh) {
  			brelse(cur_epos.bh);
  			get_bh(next_epos.bh);
  			cur_epos.bh = next_epos.bh;
  		}
  
  		lbcount += elen;
  
  		prev_epos.block = cur_epos.block;
  		cur_epos.block = next_epos.block;
  
  		prev_epos.offset = cur_epos.offset;
  		cur_epos.offset = next_epos.offset;
  
  		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 1);
  		if (etype == -1)
  			break;
  
  		c = !c;
  
  		laarr[c].extLength = (etype << 30) | elen;
  		laarr[c].extLocation = eloc;
  
  		if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
  			pgoal = eloc.logicalBlockNum +
  				((elen + inode->i_sb->s_blocksize - 1) >>
  				 inode->i_sb->s_blocksize_bits);
  
  		count++;
  	} while (lbcount + elen <= b_off);
  
  	b_off -= lbcount;
  	offset = b_off >> inode->i_sb->s_blocksize_bits;
  	/*
  	 * Move prev_epos and cur_epos into indirect extent if we are at
  	 * the pointer to it
  	 */
  	udf_next_aext(inode, &prev_epos, &tmpeloc, &tmpelen, 0);
  	udf_next_aext(inode, &cur_epos, &tmpeloc, &tmpelen, 0);
  
  	/* if the extent is allocated and recorded, return the block
  	   if the extent is not a multiple of the blocksize, round up */
  
  	if (etype == (EXT_RECORDED_ALLOCATED >> 30)) {
  		if (elen & (inode->i_sb->s_blocksize - 1)) {
  			elen = EXT_RECORDED_ALLOCATED |
  				((elen + inode->i_sb->s_blocksize - 1) &
  				 ~(inode->i_sb->s_blocksize - 1));
  			udf_write_aext(inode, &cur_epos, &eloc, elen, 1);
  		}
  		brelse(prev_epos.bh);
  		brelse(cur_epos.bh);
  		brelse(next_epos.bh);
  		newblock = udf_get_lb_pblock(inode->i_sb, &eloc, offset);
  		return newblock;
  	}
  
  	/* Are we beyond EOF? */
  	if (etype == -1) {
  		int ret;
  		isBeyondEOF = 1;
  		if (count) {
  			if (c)
  				laarr[0] = laarr[1];
  			startnum = 1;
  		} else {
  			/* Create a fake extent when there's not one */
  			memset(&laarr[0].extLocation, 0x00,
  				sizeof(struct kernel_lb_addr));
  			laarr[0].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
  			/* Will udf_do_extend_file() create real extent from
  			   a fake one? */
  			startnum = (offset > 0);
  		}
  		/* Create extents for the hole between EOF and offset */
  		ret = udf_do_extend_file(inode, &prev_epos, laarr, offset);
  		if (ret < 0) {
  			brelse(prev_epos.bh);
  			brelse(cur_epos.bh);
  			brelse(next_epos.bh);
  			*err = ret;
  			return 0;
  		}
  		c = 0;
  		offset = 0;
  		count += ret;
  		/* We are not covered by a preallocated extent? */
  		if ((laarr[0].extLength & UDF_EXTENT_FLAG_MASK) !=
  						EXT_NOT_RECORDED_ALLOCATED) {
  			/* Is there any real extent? - otherwise we overwrite
  			 * the fake one... */
  			if (count)
  				c = !c;
  			laarr[c].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
  				inode->i_sb->s_blocksize;
  			memset(&laarr[c].extLocation, 0x00,
  				sizeof(struct kernel_lb_addr));
  			count++;
  		}
  		endnum = c + 1;
  		lastblock = 1;
  	} else {
  		isBeyondEOF = 0;
  		endnum = startnum = ((count > 2) ? 2 : count);
  
  		/* if the current extent is in position 0,
  		   swap it with the previous */
  		if (!c && count != 1) {
  			laarr[2] = laarr[0];
  			laarr[0] = laarr[1];
  			laarr[1] = laarr[2];
  			c = 1;
  		}
  
  		/* if the current block is located in an extent,
  		   read the next extent */
  		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 0);
  		if (etype != -1) {
  			laarr[c + 1].extLength = (etype << 30) | elen;
  			laarr[c + 1].extLocation = eloc;
  			count++;
  			startnum++;
  			endnum++;
  		} else
  			lastblock = 1;
  	}
  
  	/* if the current extent is not recorded but allocated, get the
  	 * block in the extent corresponding to the requested block */
  	if ((laarr[c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30))
  		newblocknum = laarr[c].extLocation.logicalBlockNum + offset;
  	else { /* otherwise, allocate a new block */
  		if (iinfo->i_next_alloc_block == block)
  			goal = iinfo->i_next_alloc_goal;
  
  		if (!goal) {
  			if (!(goal = pgoal)) /* XXX: what was intended here? */
  				goal = iinfo->i_location.logicalBlockNum + 1;
  		}
  
  		newblocknum = udf_new_block(inode->i_sb, inode,
  				iinfo->i_location.partitionReferenceNum,
  				goal, err);
  		if (!newblocknum) {
  			brelse(prev_epos.bh);
  			brelse(cur_epos.bh);
  			brelse(next_epos.bh);
  			*err = -ENOSPC;
  			return 0;
  		}
  		if (isBeyondEOF)
  			iinfo->i_lenExtents += inode->i_sb->s_blocksize;
  	}
  
  	/* if the extent the requsted block is located in contains multiple
  	 * blocks, split the extent into at most three extents. blocks prior
  	 * to requested block, requested block, and blocks after requested
  	 * block */
  	udf_split_extents(inode, &c, offset, newblocknum, laarr, &endnum);
  
  #ifdef UDF_PREALLOCATE
  	/* We preallocate blocks only for regular files. It also makes sense
  	 * for directories but there's a problem when to drop the
  	 * preallocation. We might use some delayed work for that but I feel
  	 * it's overengineering for a filesystem like UDF. */
  	if (S_ISREG(inode->i_mode))
  		udf_prealloc_extents(inode, c, lastblock, laarr, &endnum);
  #endif
  
  	/* merge any continuous blocks in laarr */
  	udf_merge_extents(inode, laarr, &endnum);
  
  	/* write back the new extents, inserting new extents if the new number
  	 * of extents is greater than the old number, and deleting extents if
  	 * the new number of extents is less than the old number */
  	udf_update_extents(inode, laarr, startnum, endnum, &prev_epos);
  
  	brelse(prev_epos.bh);
  	brelse(cur_epos.bh);
  	brelse(next_epos.bh);
  
  	newblock = udf_get_pblock(inode->i_sb, newblocknum,
  				iinfo->i_location.partitionReferenceNum, 0);
  	if (!newblock) {
  		*err = -EIO;
  		return 0;
  	}
  	*new = 1;
  	iinfo->i_next_alloc_block = block;
  	iinfo->i_next_alloc_goal = newblocknum;
  	inode->i_ctime = current_fs_time(inode->i_sb);
  
  	if (IS_SYNC(inode))
  		udf_sync_inode(inode);
  	else
  		mark_inode_dirty(inode);
  
  	return newblock;
  }
  
  static void udf_split_extents(struct inode *inode, int *c, int offset,
  			      int newblocknum,
  			      struct kernel_long_ad laarr[EXTENT_MERGE_SIZE],
  			      int *endnum)
  {
  	unsigned long blocksize = inode->i_sb->s_blocksize;
  	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
  
  	if ((laarr[*c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30) ||
  	    (laarr[*c].extLength >> 30) ==
  				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
  		int curr = *c;
  		int blen = ((laarr[curr].extLength & UDF_EXTENT_LENGTH_MASK) +
  			    blocksize - 1) >> blocksize_bits;
  		int8_t etype = (laarr[curr].extLength >> 30);
  
  		if (blen == 1)
  			;
  		else if (!offset || blen == offset + 1) {
  			laarr[curr + 2] = laarr[curr + 1];
  			laarr[curr + 1] = laarr[curr];
  		} else {
  			laarr[curr + 3] = laarr[curr + 1];
  			laarr[curr + 2] = laarr[curr + 1] = laarr[curr];
  		}
  
  		if (offset) {
  			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
  				udf_free_blocks(inode->i_sb, inode,
  						&laarr[curr].extLocation,
  						0, offset);
  				laarr[curr].extLength =
  					EXT_NOT_RECORDED_NOT_ALLOCATED |
  					(offset << blocksize_bits);
  				laarr[curr].extLocation.logicalBlockNum = 0;
  				laarr[curr].extLocation.
  						partitionReferenceNum = 0;
  			} else
  				laarr[curr].extLength = (etype << 30) |
  					(offset << blocksize_bits);
  			curr++;
  			(*c)++;
  			(*endnum)++;
  		}
  
  		laarr[curr].extLocation.logicalBlockNum = newblocknum;
  		if (etype == (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
  			laarr[curr].extLocation.partitionReferenceNum =
  				UDF_I(inode)->i_location.partitionReferenceNum;
  		laarr[curr].extLength = EXT_RECORDED_ALLOCATED |
  			blocksize;
  		curr++;
  
  		if (blen != offset + 1) {
  			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
  				laarr[curr].extLocation.logicalBlockNum +=
  								offset + 1;
  			laarr[curr].extLength = (etype << 30) |
  				((blen - (offset + 1)) << blocksize_bits);
  			curr++;
  			(*endnum)++;
  		}
  	}
  }
  
  static void udf_prealloc_extents(struct inode *inode, int c, int lastblock,
  				 struct kernel_long_ad laarr[EXTENT_MERGE_SIZE],
  				 int *endnum)
  {
  	int start, length = 0, currlength = 0, i;
  
  	if (*endnum >= (c + 1)) {
  		if (!lastblock)
  			return;
  		else
  			start = c;
  	} else {
  		if ((laarr[c + 1].extLength >> 30) ==
  					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
  			start = c + 1;
  			length = currlength =
  				(((laarr[c + 1].extLength &
  					UDF_EXTENT_LENGTH_MASK) +
  				inode->i_sb->s_blocksize - 1) >>
  				inode->i_sb->s_blocksize_bits);
  		} else
  			start = c;
  	}
  
  	for (i = start + 1; i <= *endnum; i++) {
  		if (i == *endnum) {
  			if (lastblock)
  				length += UDF_DEFAULT_PREALLOC_BLOCKS;
  		} else if ((laarr[i].extLength >> 30) ==
  				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
  			length += (((laarr[i].extLength &
  						UDF_EXTENT_LENGTH_MASK) +
  				    inode->i_sb->s_blocksize - 1) >>
  				    inode->i_sb->s_blocksize_bits);
  		} else
  			break;
  	}
  
  	if (length) {
  		int next = laarr[start].extLocation.logicalBlockNum +
  			(((laarr[start].extLength & UDF_EXTENT_LENGTH_MASK) +
  			  inode->i_sb->s_blocksize - 1) >>
  			  inode->i_sb->s_blocksize_bits);
  		int numalloc = udf_prealloc_blocks(inode->i_sb, inode,
  				laarr[start].extLocation.partitionReferenceNum,
  				next, (UDF_DEFAULT_PREALLOC_BLOCKS > length ?
  				length : UDF_DEFAULT_PREALLOC_BLOCKS) -
  				currlength);
  		if (numalloc) 	{
  			if (start == (c + 1))
  				laarr[start].extLength +=
  					(numalloc <<
  					 inode->i_sb->s_blocksize_bits);
  			else {
  				memmove(&laarr[c + 2], &laarr[c + 1],
  					sizeof(struct long_ad) * (*endnum - (c + 1)));
  				(*endnum)++;
  				laarr[c + 1].extLocation.logicalBlockNum = next;
  				laarr[c + 1].extLocation.partitionReferenceNum =
  					laarr[c].extLocation.
  							partitionReferenceNum;
  				laarr[c + 1].extLength =
  					EXT_NOT_RECORDED_ALLOCATED |
  					(numalloc <<
  					 inode->i_sb->s_blocksize_bits);
  				start = c + 1;
  			}
  
  			for (i = start + 1; numalloc && i < *endnum; i++) {
  				int elen = ((laarr[i].extLength &
  						UDF_EXTENT_LENGTH_MASK) +
  					    inode->i_sb->s_blocksize - 1) >>
  					    inode->i_sb->s_blocksize_bits;
  
  				if (elen > numalloc) {
  					laarr[i].extLength -=
  						(numalloc <<
  						 inode->i_sb->s_blocksize_bits);
  					numalloc = 0;
  				} else {
  					numalloc -= elen;
  					if (*endnum > (i + 1))
  						memmove(&laarr[i],
  							&laarr[i + 1],
  							sizeof(struct long_ad) *
  							(*endnum - (i + 1)));
  					i--;
  					(*endnum)--;
  				}
  			}
  			UDF_I(inode)->i_lenExtents +=
  				numalloc << inode->i_sb->s_blocksize_bits;
  		}
  	}
  }
  
  static void udf_merge_extents(struct inode *inode,
  			      struct kernel_long_ad laarr[EXTENT_MERGE_SIZE],
  			      int *endnum)
  {
  	int i;
  	unsigned long blocksize = inode->i_sb->s_blocksize;
  	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
  
  	for (i = 0; i < (*endnum - 1); i++) {
  		struct kernel_long_ad *li /*l[i]*/ = &laarr[i];
  		struct kernel_long_ad *lip1 /*l[i plus 1]*/ = &laarr[i + 1];
  
  		if (((li->extLength >> 30) == (lip1->extLength >> 30)) &&
  			(((li->extLength >> 30) ==
  				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) ||
  			((lip1->extLocation.logicalBlockNum -
  			  li->extLocation.logicalBlockNum) ==
  			(((li->extLength & UDF_EXTENT_LENGTH_MASK) +
  			blocksize - 1) >> blocksize_bits)))) {
  
  			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
  				(lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
  				blocksize - 1) & ~UDF_EXTENT_LENGTH_MASK) {
  				lip1->extLength = (lip1->extLength -
  						  (li->extLength &
  						   UDF_EXTENT_LENGTH_MASK) +
  						   UDF_EXTENT_LENGTH_MASK) &
  							~(blocksize - 1);
  				li->extLength = (li->extLength &
  						 UDF_EXTENT_FLAG_MASK) +
  						(UDF_EXTENT_LENGTH_MASK + 1) -
  						blocksize;
  				lip1->extLocation.logicalBlockNum =
  					li->extLocation.logicalBlockNum +
  					((li->extLength &
  						UDF_EXTENT_LENGTH_MASK) >>
  						blocksize_bits);
  			} else {
  				li->extLength = lip1->extLength +
  					(((li->extLength &
  						UDF_EXTENT_LENGTH_MASK) +
  					 blocksize - 1) & ~(blocksize - 1));
  				if (*endnum > (i + 2))
  					memmove(&laarr[i + 1], &laarr[i + 2],
  						sizeof(struct long_ad) *
  						(*endnum - (i + 2)));
  				i--;
  				(*endnum)--;
  			}
  		} else if (((li->extLength >> 30) ==
  				(EXT_NOT_RECORDED_ALLOCATED >> 30)) &&
  			   ((lip1->extLength >> 30) ==
  				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))) {
  			udf_free_blocks(inode->i_sb, inode, &li->extLocation, 0,
  					((li->extLength &
  					  UDF_EXTENT_LENGTH_MASK) +
  					 blocksize - 1) >> blocksize_bits);
  			li->extLocation.logicalBlockNum = 0;
  			li->extLocation.partitionReferenceNum = 0;
  
  			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
  			     (lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
  			     blocksize - 1) & ~UDF_EXTENT_LENGTH_MASK) {
  				lip1->extLength = (lip1->extLength -
  						   (li->extLength &
  						   UDF_EXTENT_LENGTH_MASK) +
  						   UDF_EXTENT_LENGTH_MASK) &
  						   ~(blocksize - 1);
  				li->extLength = (li->extLength &
  						 UDF_EXTENT_FLAG_MASK) +
  						(UDF_EXTENT_LENGTH_MASK + 1) -
  						blocksize;
  			} else {
  				li->extLength = lip1->extLength +
  					(((li->extLength &
  						UDF_EXTENT_LENGTH_MASK) +
  					  blocksize - 1) & ~(blocksize - 1));
  				if (*endnum > (i + 2))
  					memmove(&laarr[i + 1], &laarr[i + 2],
  						sizeof(struct long_ad) *
  						(*endnum - (i + 2)));
  				i--;
  				(*endnum)--;
  			}
  		} else if ((li->extLength >> 30) ==
  					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
  			udf_free_blocks(inode->i_sb, inode,
  					&li->extLocation, 0,
  					((li->extLength &
  						UDF_EXTENT_LENGTH_MASK) +
  					 blocksize - 1) >> blocksize_bits);
  			li->extLocation.logicalBlockNum = 0;
  			li->extLocation.partitionReferenceNum = 0;
  			li->extLength = (li->extLength &
  						UDF_EXTENT_LENGTH_MASK) |
  						EXT_NOT_RECORDED_NOT_ALLOCATED;
  		}
  	}
  }
  
  static void udf_update_extents(struct inode *inode,
  			       struct kernel_long_ad laarr[EXTENT_MERGE_SIZE],
  			       int startnum, int endnum,
  			       struct extent_position *epos)
  {
  	int start = 0, i;
  	struct kernel_lb_addr tmploc;
  	uint32_t tmplen;
  
  	if (startnum > endnum) {
  		for (i = 0; i < (startnum - endnum); i++)
  			udf_delete_aext(inode, *epos, laarr[i].extLocation,
  					laarr[i].extLength);
  	} else if (startnum < endnum) {
  		for (i = 0; i < (endnum - startnum); i++) {
  			udf_insert_aext(inode, *epos, laarr[i].extLocation,
  					laarr[i].extLength);
  			udf_next_aext(inode, epos, &laarr[i].extLocation,
  				      &laarr[i].extLength, 1);
  			start++;
  		}
  	}
  
  	for (i = start; i < endnum; i++) {
  		udf_next_aext(inode, epos, &tmploc, &tmplen, 0);
  		udf_write_aext(inode, epos, &laarr[i].extLocation,
  			       laarr[i].extLength, 1);
  	}
  }
  
  struct buffer_head *udf_bread(struct inode *inode, int block,
  			      int create, int *err)
  {
  	struct buffer_head *bh = NULL;
  
  	bh = udf_getblk(inode, block, create, err);
  	if (!bh)
  		return NULL;
  
  	if (buffer_uptodate(bh))
  		return bh;
  
  	ll_rw_block(READ, 1, &bh);
  
  	wait_on_buffer(bh);
  	if (buffer_uptodate(bh))
  		return bh;
  
  	brelse(bh);
  	*err = -EIO;
  	return NULL;
  }
  
  int udf_setsize(struct inode *inode, loff_t newsize)
  {
  	int err;
  	struct udf_inode_info *iinfo;
  	int bsize = 1 << inode->i_blkbits;
  
  	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
  	      S_ISLNK(inode->i_mode)))
  		return -EINVAL;
  	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
  		return -EPERM;
  
  	iinfo = UDF_I(inode);
  	if (newsize > inode->i_size) {
  		down_write(&iinfo->i_data_sem);
  		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
  			if (bsize <
  			    (udf_file_entry_alloc_offset(inode) + newsize)) {
  				err = udf_expand_file_adinicb(inode);
  				if (err)
  					return err;
  				down_write(&iinfo->i_data_sem);
  			} else {
  				iinfo->i_lenAlloc = newsize;
  				goto set_size;
  			}
  		}
  		err = udf_extend_file(inode, newsize);
  		if (err) {
  			up_write(&iinfo->i_data_sem);
  			return err;
  		}
  set_size:
  		truncate_setsize(inode, newsize);
  		up_write(&iinfo->i_data_sem);
  	} else {
  		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
  			down_write(&iinfo->i_data_sem);
  			udf_clear_extent_cache(inode);
  			memset(iinfo->i_ext.i_data + iinfo->i_lenEAttr + newsize,
  			       0x00, bsize - newsize -
  			       udf_file_entry_alloc_offset(inode));
  			iinfo->i_lenAlloc = newsize;
  			truncate_setsize(inode, newsize);
  			up_write(&iinfo->i_data_sem);
  			goto update_time;
  		}
  		err = block_truncate_page(inode->i_mapping, newsize,
  					  udf_get_block);
  		if (err)
  			return err;
  		down_write(&iinfo->i_data_sem);
  		udf_clear_extent_cache(inode);
  		truncate_setsize(inode, newsize);
  		udf_truncate_extents(inode);
  		up_write(&iinfo->i_data_sem);
  	}
  update_time:
  	inode->i_mtime = inode->i_ctime = current_fs_time(inode->i_sb);
  	if (IS_SYNC(inode))
  		udf_sync_inode(inode);
  	else
  		mark_inode_dirty(inode);
  	return 0;
  }
  
  static void __udf_read_inode(struct inode *inode)
  {
  	struct buffer_head *bh = NULL;
  	struct fileEntry *fe;
  	uint16_t ident;
  	struct udf_inode_info *iinfo = UDF_I(inode);
  
  	/*
  	 * Set defaults, but the inode is still incomplete!
  	 * Note: get_new_inode() sets the following on a new inode:
  	 *      i_sb = sb
  	 *      i_no = ino
  	 *      i_flags = sb->s_flags
  	 *      i_state = 0
  	 * clean_inode(): zero fills and sets
  	 *      i_count = 1
  	 *      i_nlink = 1
  	 *      i_op = NULL;
  	 */
  	bh = udf_read_ptagged(inode->i_sb, &iinfo->i_location, 0, &ident);
  	if (!bh) {
  		udf_err(inode->i_sb, "(ino %ld) failed !bh\n", inode->i_ino);
  		make_bad_inode(inode);
  		return;
  	}
  
  	if (ident != TAG_IDENT_FE && ident != TAG_IDENT_EFE &&
  	    ident != TAG_IDENT_USE) {
  		udf_err(inode->i_sb, "(ino %ld) failed ident=%d\n",
  			inode->i_ino, ident);
  		brelse(bh);
  		make_bad_inode(inode);
  		return;
  	}
  
  	fe = (struct fileEntry *)bh->b_data;
  
  	if (fe->icbTag.strategyType == cpu_to_le16(4096)) {
  		struct buffer_head *ibh;
  
  		ibh = udf_read_ptagged(inode->i_sb, &iinfo->i_location, 1,
  					&ident);
  		if (ident == TAG_IDENT_IE && ibh) {
  			struct buffer_head *nbh = NULL;
  			struct kernel_lb_addr loc;
  			struct indirectEntry *ie;
  
  			ie = (struct indirectEntry *)ibh->b_data;
  			loc = lelb_to_cpu(ie->indirectICB.extLocation);
  
  			if (ie->indirectICB.extLength &&
  				(nbh = udf_read_ptagged(inode->i_sb, &loc, 0,
  							&ident))) {
  				if (ident == TAG_IDENT_FE ||
  					ident == TAG_IDENT_EFE) {
  					memcpy(&iinfo->i_location,
  						&loc,
  						sizeof(struct kernel_lb_addr));
  					brelse(bh);
  					brelse(ibh);
  					brelse(nbh);
  					__udf_read_inode(inode);
  					return;
  				}
  				brelse(nbh);
  			}
  		}
  		brelse(ibh);
  	} else if (fe->icbTag.strategyType != cpu_to_le16(4)) {
  		udf_err(inode->i_sb, "unsupported strategy type: %d\n",
  			le16_to_cpu(fe->icbTag.strategyType));
  		brelse(bh);
  		make_bad_inode(inode);
  		return;
  	}
  	udf_fill_inode(inode, bh);
  
  	brelse(bh);
  }
  
  static void udf_fill_inode(struct inode *inode, struct buffer_head *bh)
  {
  	struct fileEntry *fe;
  	struct extendedFileEntry *efe;
  	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
  	struct udf_inode_info *iinfo = UDF_I(inode);
  	unsigned int link_count;
  
  	fe = (struct fileEntry *)bh->b_data;
  	efe = (struct extendedFileEntry *)bh->b_data;
  
  	if (fe->icbTag.strategyType == cpu_to_le16(4))
  		iinfo->i_strat4096 = 0;
  	else /* if (fe->icbTag.strategyType == cpu_to_le16(4096)) */
  		iinfo->i_strat4096 = 1;
  
  	iinfo->i_alloc_type = le16_to_cpu(fe->icbTag.flags) &
  							ICBTAG_FLAG_AD_MASK;
  	iinfo->i_unique = 0;
  	iinfo->i_lenEAttr = 0;
  	iinfo->i_lenExtents = 0;
  	iinfo->i_lenAlloc = 0;
  	iinfo->i_next_alloc_block = 0;
  	iinfo->i_next_alloc_goal = 0;
  	if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_EFE)) {
  		iinfo->i_efe = 1;
  		iinfo->i_use = 0;
  		if (udf_alloc_i_data(inode, inode->i_sb->s_blocksize -
  					sizeof(struct extendedFileEntry))) {
  			make_bad_inode(inode);
  			return;
  		}
  		memcpy(iinfo->i_ext.i_data,
  		       bh->b_data + sizeof(struct extendedFileEntry),
  		       inode->i_sb->s_blocksize -
  					sizeof(struct extendedFileEntry));
  	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_FE)) {
  		iinfo->i_efe = 0;
  		iinfo->i_use = 0;
  		if (udf_alloc_i_data(inode, inode->i_sb->s_blocksize -
  						sizeof(struct fileEntry))) {
  			make_bad_inode(inode);
  			return;
  		}
  		memcpy(iinfo->i_ext.i_data,
  		       bh->b_data + sizeof(struct fileEntry),
  		       inode->i_sb->s_blocksize - sizeof(struct fileEntry));
  	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_USE)) {
  		iinfo->i_efe = 0;
  		iinfo->i_use = 1;
  		iinfo->i_lenAlloc = le32_to_cpu(
  				((struct unallocSpaceEntry *)bh->b_data)->
  				 lengthAllocDescs);
  		if (udf_alloc_i_data(inode, inode->i_sb->s_blocksize -
  					sizeof(struct unallocSpaceEntry))) {
  			make_bad_inode(inode);
  			return;
  		}
  		memcpy(iinfo->i_ext.i_data,
  		       bh->b_data + sizeof(struct unallocSpaceEntry),
  		       inode->i_sb->s_blocksize -
  					sizeof(struct unallocSpaceEntry));
  		return;
  	}
  
  	read_lock(&sbi->s_cred_lock);
  	i_uid_write(inode, le32_to_cpu(fe->uid));
  	if (!uid_valid(inode->i_uid) ||
  	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_IGNORE) ||
  	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_SET))
  		inode->i_uid = UDF_SB(inode->i_sb)->s_uid;
  
  	i_gid_write(inode, le32_to_cpu(fe->gid));
  	if (!gid_valid(inode->i_gid) ||
  	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_IGNORE) ||
  	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_SET))
  		inode->i_gid = UDF_SB(inode->i_sb)->s_gid;
  
  	if (fe->icbTag.fileType != ICBTAG_FILE_TYPE_DIRECTORY &&
  			sbi->s_fmode != UDF_INVALID_MODE)
  		inode->i_mode = sbi->s_fmode;
  	else if (fe->icbTag.fileType == ICBTAG_FILE_TYPE_DIRECTORY &&
  			sbi->s_dmode != UDF_INVALID_MODE)
  		inode->i_mode = sbi->s_dmode;
  	else
  		inode->i_mode = udf_convert_permissions(fe);
  	inode->i_mode &= ~sbi->s_umask;
  	read_unlock(&sbi->s_cred_lock);
  
  	link_count = le16_to_cpu(fe->fileLinkCount);
  	if (!link_count)
  		link_count = 1;
  	set_nlink(inode, link_count);
  
  	inode->i_size = le64_to_cpu(fe->informationLength);
  	iinfo->i_lenExtents = inode->i_size;
  
  	if (iinfo->i_efe == 0) {
  		inode->i_blocks = le64_to_cpu(fe->logicalBlocksRecorded) <<
  			(inode->i_sb->s_blocksize_bits - 9);
  
  		if (!udf_disk_stamp_to_time(&inode->i_atime, fe->accessTime))
  			inode->i_atime = sbi->s_record_time;
  
  		if (!udf_disk_stamp_to_time(&inode->i_mtime,
  					    fe->modificationTime))
  			inode->i_mtime = sbi->s_record_time;
  
  		if (!udf_disk_stamp_to_time(&inode->i_ctime, fe->attrTime))
  			inode->i_ctime = sbi->s_record_time;
  
  		iinfo->i_unique = le64_to_cpu(fe->uniqueID);
  		iinfo->i_lenEAttr = le32_to_cpu(fe->lengthExtendedAttr);
  		iinfo->i_lenAlloc = le32_to_cpu(fe->lengthAllocDescs);
  		iinfo->i_checkpoint = le32_to_cpu(fe->checkpoint);
  	} else {
  		inode->i_blocks = le64_to_cpu(efe->logicalBlocksRecorded) <<
  		    (inode->i_sb->s_blocksize_bits - 9);
  
  		if (!udf_disk_stamp_to_time(&inode->i_atime, efe->accessTime))
  			inode->i_atime = sbi->s_record_time;
  
  		if (!udf_disk_stamp_to_time(&inode->i_mtime,
  					    efe->modificationTime))
  			inode->i_mtime = sbi->s_record_time;
  
  		if (!udf_disk_stamp_to_time(&iinfo->i_crtime, efe->createTime))
  			iinfo->i_crtime = sbi->s_record_time;
  
  		if (!udf_disk_stamp_to_time(&inode->i_ctime, efe->attrTime))
  			inode->i_ctime = sbi->s_record_time;
  
  		iinfo->i_unique = le64_to_cpu(efe->uniqueID);
  		iinfo->i_lenEAttr = le32_to_cpu(efe->lengthExtendedAttr);
  		iinfo->i_lenAlloc = le32_to_cpu(efe->lengthAllocDescs);
  		iinfo->i_checkpoint = le32_to_cpu(efe->checkpoint);
  	}
  
  	switch (fe->icbTag.fileType) {
  	case ICBTAG_FILE_TYPE_DIRECTORY:
  		inode->i_op = &udf_dir_inode_operations;
  		inode->i_fop = &udf_dir_operations;
  		inode->i_mode |= S_IFDIR;
  		inc_nlink(inode);
  		break;
  	case ICBTAG_FILE_TYPE_REALTIME:
  	case ICBTAG_FILE_TYPE_REGULAR:
  	case ICBTAG_FILE_TYPE_UNDEF:
  	case ICBTAG_FILE_TYPE_VAT20:
  		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
  			inode->i_data.a_ops = &udf_adinicb_aops;
  		else
  			inode->i_data.a_ops = &udf_aops;
  		inode->i_op = &udf_file_inode_operations;
  		inode->i_fop = &udf_file_operations;
  		inode->i_mode |= S_IFREG;
  		break;
  	case ICBTAG_FILE_TYPE_BLOCK:
  		inode->i_mode |= S_IFBLK;
  		break;
  	case ICBTAG_FILE_TYPE_CHAR:
  		inode->i_mode |= S_IFCHR;
  		break;
  	case ICBTAG_FILE_TYPE_FIFO:
  		init_special_inode(inode, inode->i_mode | S_IFIFO, 0);
  		break;
  	case ICBTAG_FILE_TYPE_SOCKET:
  		init_special_inode(inode, inode->i_mode | S_IFSOCK, 0);
  		break;
  	case ICBTAG_FILE_TYPE_SYMLINK:
  		inode->i_data.a_ops = &udf_symlink_aops;
  		inode->i_op = &udf_symlink_inode_operations;
  		inode->i_mode = S_IFLNK | S_IRWXUGO;
  		break;
  	case ICBTAG_FILE_TYPE_MAIN:
  		udf_debug("METADATA FILE-----\n");
  		break;
  	case ICBTAG_FILE_TYPE_MIRROR:
  		udf_debug("METADATA MIRROR FILE-----\n");
  		break;
  	case ICBTAG_FILE_TYPE_BITMAP:
  		udf_debug("METADATA BITMAP FILE-----\n");
  		break;
  	default:
  		udf_err(inode->i_sb, "(ino %ld) failed unknown file type=%d\n",
  			inode->i_ino, fe->icbTag.fileType);
  		make_bad_inode(inode);
  		return;
  	}
  	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
  		struct deviceSpec *dsea =
  			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
  		if (dsea) {
  			init_special_inode(inode, inode->i_mode,
  				MKDEV(le32_to_cpu(dsea->majorDeviceIdent),
  				      le32_to_cpu(dsea->minorDeviceIdent)));
  			/* Developer ID ??? */
  		} else
  			make_bad_inode(inode);
  	}
  }
  
  static int udf_alloc_i_data(struct inode *inode, size_t size)
  {
  	struct udf_inode_info *iinfo = UDF_I(inode);
  	iinfo->i_ext.i_data = kmalloc(size, GFP_KERNEL);
  
  	if (!iinfo->i_ext.i_data) {
  		udf_err(inode->i_sb, "(ino %ld) no free memory\n",
  			inode->i_ino);
  		return -ENOMEM;
  	}
  
  	return 0;
  }
  
  static umode_t udf_convert_permissions(struct fileEntry *fe)
  {
  	umode_t mode;
  	uint32_t permissions;
  	uint32_t flags;
  
  	permissions = le32_to_cpu(fe->permissions);
  	flags = le16_to_cpu(fe->icbTag.flags);
  
  	mode =	((permissions) & S_IRWXO) |
  		((permissions >> 2) & S_IRWXG) |
  		((permissions >> 4) & S_IRWXU) |
  		((flags & ICBTAG_FLAG_SETUID) ? S_ISUID : 0) |
  		((flags & ICBTAG_FLAG_SETGID) ? S_ISGID : 0) |
  		((flags & ICBTAG_FLAG_STICKY) ? S_ISVTX : 0);
  
  	return mode;
  }
  
  int udf_write_inode(struct inode *inode, struct writeback_control *wbc)
  {
  	return udf_update_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
  }
  
  static int udf_sync_inode(struct inode *inode)
  {
  	return udf_update_inode(inode, 1);
  }
  
  static int udf_update_inode(struct inode *inode, int do_sync)
  {
  	struct buffer_head *bh = NULL;
  	struct fileEntry *fe;
  	struct extendedFileEntry *efe;
  	uint64_t lb_recorded;
  	uint32_t udfperms;
  	uint16_t icbflags;
  	uint16_t crclen;
  	int err = 0;
  	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
  	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
  	struct udf_inode_info *iinfo = UDF_I(inode);
  
  	bh = udf_tgetblk(inode->i_sb,
  			udf_get_lb_pblock(inode->i_sb, &iinfo->i_location, 0));
  	if (!bh) {
  		udf_debug("getblk failure\n");
  		return -ENOMEM;
  	}
  
  	lock_buffer(bh);
  	memset(bh->b_data, 0, inode->i_sb->s_blocksize);
  	fe = (struct fileEntry *)bh->b_data;
  	efe = (struct extendedFileEntry *)bh->b_data;
  
  	if (iinfo->i_use) {
  		struct unallocSpaceEntry *use =
  			(struct unallocSpaceEntry *)bh->b_data;
  
  		use->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
  		memcpy(bh->b_data + sizeof(struct unallocSpaceEntry),
  		       iinfo->i_ext.i_data, inode->i_sb->s_blocksize -
  					sizeof(struct unallocSpaceEntry));
  		use->descTag.tagIdent = cpu_to_le16(TAG_IDENT_USE);
  		use->descTag.tagLocation =
  				cpu_to_le32(iinfo->i_location.logicalBlockNum);
  		crclen = sizeof(struct unallocSpaceEntry) +
  				iinfo->i_lenAlloc - sizeof(struct tag);
  		use->descTag.descCRCLength = cpu_to_le16(crclen);
  		use->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)use +
  							   sizeof(struct tag),
  							   crclen));
  		use->descTag.tagChecksum = udf_tag_checksum(&use->descTag);
  
  		goto out;
  	}
  
  	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_FORGET))
  		fe->uid = cpu_to_le32(-1);
  	else
  		fe->uid = cpu_to_le32(i_uid_read(inode));
  
  	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_FORGET))
  		fe->gid = cpu_to_le32(-1);
  	else
  		fe->gid = cpu_to_le32(i_gid_read(inode));
  
  	udfperms = ((inode->i_mode & S_IRWXO)) |
  		   ((inode->i_mode & S_IRWXG) << 2) |
  		   ((inode->i_mode & S_IRWXU) << 4);
  
  	udfperms |= (le32_to_cpu(fe->permissions) &
  		    (FE_PERM_O_DELETE | FE_PERM_O_CHATTR |
  		     FE_PERM_G_DELETE | FE_PERM_G_CHATTR |
  		     FE_PERM_U_DELETE | FE_PERM_U_CHATTR));
  	fe->permissions = cpu_to_le32(udfperms);
  
  	if (S_ISDIR(inode->i_mode))
  		fe->fileLinkCount = cpu_to_le16(inode->i_nlink - 1);
  	else
  		fe->fileLinkCount = cpu_to_le16(inode->i_nlink);
  
  	fe->informationLength = cpu_to_le64(inode->i_size);
  
  	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
  		struct regid *eid;
  		struct deviceSpec *dsea =
  			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
  		if (!dsea) {
  			dsea = (struct deviceSpec *)
  				udf_add_extendedattr(inode,
  						     sizeof(struct deviceSpec) +
  						     sizeof(struct regid), 12, 0x3);
  			dsea->attrType = cpu_to_le32(12);
  			dsea->attrSubtype = 1;
  			dsea->attrLength = cpu_to_le32(
  						sizeof(struct deviceSpec) +
  						sizeof(struct regid));
  			dsea->impUseLength = cpu_to_le32(sizeof(struct regid));
  		}
  		eid = (struct regid *)dsea->impUse;
  		memset(eid, 0, sizeof(struct regid));
  		strcpy(eid->ident, UDF_ID_DEVELOPER);
  		eid->identSuffix[0] = UDF_OS_CLASS_UNIX;
  		eid->identSuffix[1] = UDF_OS_ID_LINUX;
  		dsea->majorDeviceIdent = cpu_to_le32(imajor(inode));
  		dsea->minorDeviceIdent = cpu_to_le32(iminor(inode));
  	}
  
  	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
  		lb_recorded = 0; /* No extents => no blocks! */
  	else
  		lb_recorded =
  			(inode->i_blocks + (1 << (blocksize_bits - 9)) - 1) >>
  			(blocksize_bits - 9);
  
  	if (iinfo->i_efe == 0) {
  		memcpy(bh->b_data + sizeof(struct fileEntry),
  		       iinfo->i_ext.i_data,
  		       inode->i_sb->s_blocksize - sizeof(struct fileEntry));
  		fe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
  
  		udf_time_to_disk_stamp(&fe->accessTime, inode->i_atime);
  		udf_time_to_disk_stamp(&fe->modificationTime, inode->i_mtime);
  		udf_time_to_disk_stamp(&fe->attrTime, inode->i_ctime);
  		memset(&(fe->impIdent), 0, sizeof(struct regid));
  		strcpy(fe->impIdent.ident, UDF_ID_DEVELOPER);
  		fe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
  		fe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
  		fe->uniqueID = cpu_to_le64(iinfo->i_unique);
  		fe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
  		fe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
  		fe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
  		fe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_FE);
  		crclen = sizeof(struct fileEntry);
  	} else {
  		memcpy(bh->b_data + sizeof(struct extendedFileEntry),
  		       iinfo->i_ext.i_data,
  		       inode->i_sb->s_blocksize -
  					sizeof(struct extendedFileEntry));
  		efe->objectSize = cpu_to_le64(inode->i_size);
  		efe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
  
  		if (iinfo->i_crtime.tv_sec > inode->i_atime.tv_sec ||
  		    (iinfo->i_crtime.tv_sec == inode->i_atime.tv_sec &&
  		     iinfo->i_crtime.tv_nsec > inode->i_atime.tv_nsec))
  			iinfo->i_crtime = inode->i_atime;
  
  		if (iinfo->i_crtime.tv_sec > inode->i_mtime.tv_sec ||
  		    (iinfo->i_crtime.tv_sec == inode->i_mtime.tv_sec &&
  		     iinfo->i_crtime.tv_nsec > inode->i_mtime.tv_nsec))
  			iinfo->i_crtime = inode->i_mtime;
  
  		if (iinfo->i_crtime.tv_sec > inode->i_ctime.tv_sec ||
  		    (iinfo->i_crtime.tv_sec == inode->i_ctime.tv_sec &&
  		     iinfo->i_crtime.tv_nsec > inode->i_ctime.tv_nsec))
  			iinfo->i_crtime = inode->i_ctime;
  
  		udf_time_to_disk_stamp(&efe->accessTime, inode->i_atime);
  		udf_time_to_disk_stamp(&efe->modificationTime, inode->i_mtime);
  		udf_time_to_disk_stamp(&efe->createTime, iinfo->i_crtime);
  		udf_time_to_disk_stamp(&efe->attrTime, inode->i_ctime);
  
  		memset(&(efe->impIdent), 0, sizeof(struct regid));
  		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(iinfo->i_unique);
  		efe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
  		efe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
  		efe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
  		efe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EFE);
  		crclen = sizeof(struct extendedFileEntry);
  	}
  	if (iinfo->i_strat4096) {
  		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 =	iinfo->i_alloc_type |
  			((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 (sbi->s_udfrev >= 0x0200)
  		fe->descTag.descVersion = cpu_to_le16(3);
  	else
  		fe->descTag.descVersion = cpu_to_le16(2);
  	fe->descTag.tagSerialNum = cpu_to_le16(sbi->s_serial_number);
  	fe->descTag.tagLocation = cpu_to_le32(
  					iinfo->i_location.logicalBlockNum);
  	crclen += iinfo->i_lenEAttr + iinfo->i_lenAlloc - sizeof(struct tag);
  	fe->descTag.descCRCLength = cpu_to_le16(crclen);
  	fe->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)fe + sizeof(struct tag),
  						  crclen));
  	fe->descTag.tagChecksum = udf_tag_checksum(&fe->descTag);
  
  out:
  	set_buffer_uptodate(bh);
  	unlock_buffer(bh);
  
  	/* write the data blocks */
  	mark_buffer_dirty(bh);
  	if (do_sync) {
  		sync_dirty_buffer(bh);
  		if (buffer_write_io_error(bh)) {
  			udf_warn(inode->i_sb, "IO error syncing udf inode [%08lx]\n",
  				 inode->i_ino);
  			err = -EIO;
  		}
  	}
  	brelse(bh);
  
  	return err;
  }
  
  struct inode *udf_iget(struct super_block *sb, struct 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(inode)->i_location, ino, sizeof(struct kernel_lb_addr));
  		__udf_read_inode(inode);
  		unlock_new_inode(inode);
  	}
  
  	if (is_bad_inode(inode))
  		goto out_iput;
  
  	if (ino->logicalBlockNum >= UDF_SB(sb)->
  			s_partmaps[ino->partitionReferenceNum].s_partition_len) {
  		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;
  }
  
  int udf_add_aext(struct inode *inode, struct extent_position *epos,
  		 struct kernel_lb_addr *eloc, uint32_t elen, int inc)
  {
  	int adsize;
  	struct short_ad *sad = NULL;
  	struct long_ad *lad = NULL;
  	struct allocExtDesc *aed;
  	uint8_t *ptr;
  	struct udf_inode_info *iinfo = UDF_I(inode);
  
  	if (!epos->bh)
  		ptr = iinfo->i_ext.i_data + epos->offset -
  			udf_file_entry_alloc_offset(inode) +
  			iinfo->i_lenEAttr;
  	else
  		ptr = epos->bh->b_data + epos->offset;
  
  	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
  		adsize = sizeof(struct short_ad);
  	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
  		adsize = sizeof(struct long_ad);
  	else
  		return -EIO;
  
  	if (epos->offset + (2 * adsize) > inode->i_sb->s_blocksize) {
  		unsigned char *sptr, *dptr;
  		struct buffer_head *nbh;
  		int err, loffset;
  		struct kernel_lb_addr obloc = epos->block;
  
  		epos->block.logicalBlockNum = udf_new_block(inode->i_sb, NULL,
  						obloc.partitionReferenceNum,
  						obloc.logicalBlockNum, &err);
  		if (!epos->block.logicalBlockNum)
  			return -ENOSPC;
  		nbh = udf_tgetblk(inode->i_sb, udf_get_lb_pblock(inode->i_sb,
  								 &epos->block,
  								 0));
  		if (!nbh)
  			return -EIO;
  		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;
  				le32_add_cpu(&aed->lengthAllocDescs, adsize);
  			} else {
  				iinfo->i_lenAlloc += adsize;
  				mark_inode_dirty(inode);
  			}
  		}
  		if (UDF_SB(inode->i_sb)->s_udfrev >= 0x0200)
  			udf_new_tag(nbh->b_data, TAG_IDENT_AED, 3, 1,
  				    epos->block.logicalBlockNum, sizeof(struct tag));
  		else
  			udf_new_tag(nbh->b_data, TAG_IDENT_AED, 2, 1,
  				    epos->block.logicalBlockNum, sizeof(struct tag));
  		switch (iinfo->i_alloc_type) {
  		case ICBTAG_FLAG_AD_SHORT:
  			sad = (struct 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 = (struct 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(inode->i_sb)->s_udfrev >= 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;
  	}
  
  	udf_write_aext(inode, epos, eloc, elen, inc);
  
  	if (!epos->bh) {
  		iinfo->i_lenAlloc += adsize;
  		mark_inode_dirty(inode);
  	} else {
  		aed = (struct allocExtDesc *)epos->bh->b_data;
  		le32_add_cpu(&aed->lengthAllocDescs, adsize);
  		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
  				UDF_SB(inode->i_sb)->s_udfrev >= 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 0;
  }
  
  void udf_write_aext(struct inode *inode, struct extent_position *epos,
  		    struct kernel_lb_addr *eloc, uint32_t elen, int inc)
  {
  	int adsize;
  	uint8_t *ptr;
  	struct short_ad *sad;
  	struct long_ad *lad;
  	struct udf_inode_info *iinfo = UDF_I(inode);
  
  	if (!epos->bh)
  		ptr = iinfo->i_ext.i_data + epos->offset -
  			udf_file_entry_alloc_offset(inode) +
  			iinfo->i_lenEAttr;
  	else
  		ptr = epos->bh->b_data + epos->offset;
  
  	switch (iinfo->i_alloc_type) {
  	case ICBTAG_FLAG_AD_SHORT:
  		sad = (struct short_ad *)ptr;
  		sad->extLength = cpu_to_le32(elen);
  		sad->extPosition = cpu_to_le32(eloc->logicalBlockNum);
  		adsize = sizeof(struct short_ad);
  		break;
  	case ICBTAG_FLAG_AD_LONG:
  		lad = (struct long_ad *)ptr;
  		lad->extLength = cpu_to_le32(elen);
  		lad->extLocation = cpu_to_lelb(*eloc);
  		memset(lad->impUse, 0x00, sizeof(lad->impUse));
  		adsize = sizeof(struct long_ad);
  		break;
  	default:
  		return;
  	}
  
  	if (epos->bh) {
  		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
  		    UDF_SB(inode->i_sb)->s_udfrev >= 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;
  }
  
  int8_t udf_next_aext(struct inode *inode, struct extent_position *epos,
  		     struct 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)) {
  		int block;
  		epos->block = *eloc;
  		epos->offset = sizeof(struct allocExtDesc);
  		brelse(epos->bh);
  		block = udf_get_lb_pblock(inode->i_sb, &epos->block, 0);
  		epos->bh = udf_tread(inode->i_sb, block);
  		if (!epos->bh) {
  			udf_debug("reading block %d failed!\n", block);
  			return -1;
  		}
  	}
  
  	return etype;
  }
  
  int8_t udf_current_aext(struct inode *inode, struct extent_position *epos,
  			struct kernel_lb_addr *eloc, uint32_t *elen, int inc)
  {
  	int alen;
  	int8_t etype;
  	uint8_t *ptr;
  	struct short_ad *sad;
  	struct long_ad *lad;
  	struct udf_inode_info *iinfo = UDF_I(inode);
  
  	if (!epos->bh) {
  		if (!epos->offset)
  			epos->offset = udf_file_entry_alloc_offset(inode);
  		ptr = iinfo->i_ext.i_data + epos->offset -
  			udf_file_entry_alloc_offset(inode) +
  			iinfo->i_lenEAttr;
  		alen = udf_file_entry_alloc_offset(inode) +
  							iinfo->i_lenAlloc;
  	} 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 (iinfo->i_alloc_type) {
  	case ICBTAG_FLAG_AD_SHORT:
  		sad = udf_get_fileshortad(ptr, alen, &epos->offset, inc);
  		if (!sad)
  			return -1;
  		etype = le32_to_cpu(sad->extLength) >> 30;
  		eloc->logicalBlockNum = le32_to_cpu(sad->extPosition);
  		eloc->partitionReferenceNum =
  				iinfo->i_location.partitionReferenceNum;
  		*elen = le32_to_cpu(sad->extLength) & UDF_EXTENT_LENGTH_MASK;
  		break;
  	case ICBTAG_FLAG_AD_LONG:
  		lad = udf_get_filelongad(ptr, alen, &epos->offset, inc);
  		if (!lad)
  			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", iinfo->i_alloc_type);
  		return -1;
  	}
  
  	return etype;
  }
  
  static int8_t udf_insert_aext(struct inode *inode, struct extent_position epos,
  			      struct kernel_lb_addr neloc, uint32_t nelen)
  {
  	struct 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,
  		       struct kernel_lb_addr eloc, uint32_t elen)
  {
  	struct extent_position oepos;
  	int adsize;
  	int8_t etype;
  	struct allocExtDesc *aed;
  	struct udf_inode_info *iinfo;
  
  	if (epos.bh) {
  		get_bh(epos.bh);
  		get_bh(epos.bh);
  	}
  
  	iinfo = UDF_I(inode);
  	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
  		adsize = sizeof(struct short_ad);
  	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
  		adsize = sizeof(struct 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(struct 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) {
  			iinfo->i_lenAlloc -= (adsize * 2);
  			mark_inode_dirty(inode);
  		} else {
  			aed = (struct allocExtDesc *)oepos.bh->b_data;
  			le32_add_cpu(&aed->lengthAllocDescs, -(2 * adsize));
  			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
  			    UDF_SB(inode->i_sb)->s_udfrev >= 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) {
  			iinfo->i_lenAlloc -= adsize;
  			mark_inode_dirty(inode);
  		} else {
  			aed = (struct allocExtDesc *)oepos.bh->b_data;
  			le32_add_cpu(&aed->lengthAllocDescs, -adsize);
  			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
  			    UDF_SB(inode->i_sb)->s_udfrev >= 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, struct kernel_lb_addr *eloc,
  		  uint32_t *elen, sector_t *offset)
  {
  	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
  	loff_t lbcount = 0, bcount =
  	    (loff_t) block << blocksize_bits;
  	int8_t etype;
  	struct udf_inode_info *iinfo;
  
  	iinfo = UDF_I(inode);
  	if (!udf_read_extent_cache(inode, bcount, &lbcount, pos)) {
  		pos->offset = 0;
  		pos->block = iinfo->i_location;
  		pos->bh = NULL;
  	}
  	*elen = 0;
  	do {
  		etype = udf_next_aext(inode, pos, eloc, elen, 1);
  		if (etype == -1) {
  			*offset = (bcount - lbcount) >> blocksize_bits;
  			iinfo->i_lenExtents = lbcount;
  			return -1;
  		}
  		lbcount += *elen;
  	} while (lbcount <= bcount);
  	/* update extent cache */
  	udf_update_extent_cache(inode, lbcount - *elen, pos, 1);
  	*offset = (bcount + *elen - lbcount) >> blocksize_bits;
  
  	return etype;
  }
  
  long udf_block_map(struct inode *inode, sector_t block)
  {
  	struct kernel_lb_addr eloc;
  	uint32_t elen;
  	sector_t offset;
  	struct extent_position epos = {};
  	int ret;
  
  	down_read(&UDF_I(inode)->i_data_sem);
  
  	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;
  
  	up_read(&UDF_I(inode)->i_data_sem);
  	brelse(epos.bh);
  
  	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_VARCONV))
  		return udf_fixed_to_variable(ret);
  	else
  		return ret;
  }
  