Release 4.10 fs/udf/inode.c

/*
 * 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/writeback.h>
#include <linux/slab.h>
#include <linux/crc-itu-t.h>
#include <linux/mpage.h>
#include <linux/uio.h>
#include <linux/bio.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 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;
	}
}

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/* 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);
}

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/* 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;
}

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/* 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);
}

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namjae jeon
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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));
	}
	truncate_inode_pages_final(&inode->i_data);
	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);
	}
}

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jan kara
jan kara
54
32.73%
5
27.78%
al viro
al viro
44
26.67%
2
11.11%
pre-git
pre-git
29
17.58%
3
16.67%
marcin slusarz
marcin slusarz
13
7.88%
2
11.11%
christoph hellwig
christoph hellwig
7
4.24%
1
5.56%
namjae jeon
namjae jeon
5
3.03%
1
5.56%
ben fennema
ben fennema
5
3.03%
1
5.56%
linus torvalds
linus torvalds
4
2.42%
1
5.56%
joe perches
joe perches
3
1.82%
1
5.56%
johannes weiner
johannes weiner
1
0.61%
1
5.56%
Total
165
100.00%
18
100.00%



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);
		}
	}
}

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ian abbott
ian abbott
86
94.51%
1
50.00%
namjae jeon
namjae jeon
5
5.49%
1
50.00%
Total
91
100.00%
2
100.00%



static int udf_writepage(struct page *page, struct writeback_control *wbc)
{
	return block_write_full_page(page, udf_get_block, wbc);
}

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pre-git
19
73.08%
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andrew morton
andrew morton
7
26.92%
1
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26
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100.00%



static int udf_writepages(struct address_space *mapping,
			struct writeback_control *wbc)
{
	return mpage_writepages(mapping, wbc, udf_get_block);
}

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namjae jeon
namjae jeon
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static int udf_readpage(struct file *file, struct page *page)
{
	return mpage_readpage(page, udf_get_block);
}

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23
95.83%
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66.67%
namjae jeon
namjae jeon
1
4.17%
1
33.33%
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24
100.00%
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100.00%



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);
}

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namjae jeon
namjae jeon
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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;
}

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nick piggin
nick piggin
29
38.67%
1
20.00%
pre-git
pre-git
21
28.00%
2
40.00%
ian abbott
ian abbott
13
17.33%
1
20.00%
christoph hellwig
christoph hellwig
12
16.00%
1
20.00%
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75
100.00%
5
100.00%



static ssize_t udf_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
{
	struct file *file = iocb->ki_filp;
	struct address_space *mapping = file->f_mapping;
	struct inode *inode = mapping->host;
	size_t count = iov_iter_count(iter);
	ssize_t ret;

	ret = blockdev_direct_IO(iocb, inode, iter, udf_get_block);
	if (unlikely(ret < 0 && iov_iter_rw(iter) == WRITE))
		udf_write_failed(mapping, iocb->ki_pos + count);
	return ret;
}

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ian abbott
ian abbott
47
48.45%
1
12.50%
jan kara
jan kara
17
17.53%
1
12.50%
christoph hellwig
christoph hellwig
14
14.43%
2
25.00%
al viro
al viro
12
12.37%
2
25.00%
omar sandoval
omar sandoval
5
5.15%
1
12.50%
pre-git
pre-git
2
2.06%
1
12.50%
Total
97
100.00%
8
100.00%



static sector_t udf_bmap(struct address_space *mapping, sector_t block)
{
	return generic_block_bmap(mapping, block, udf_get_block);
}

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22
91.67%
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andrew morton
andrew morton
2
8.33%
1
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24
100.00%
2
100.00%


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,
        };

	WARN_ON_ONCE(!inode_is_locked(inode));
	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_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);
	}
	put_page(page);
	mark_inode_dirty(inode);

	return err;
}

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jan kara
jan kara
162
40.70%
3
16.67%
pre-git
pre-git
146
36.68%
6
33.33%
marcin slusarz
marcin slusarz
56
14.07%
2
11.11%
andrew morton
andrew morton
20
5.03%
2
11.11%
linus torvalds
linus torvalds
6
1.51%
1
5.56%
ben fennema
ben fennema
5
1.26%
2
11.11%
kirill a. shutemov
kirill a. shutemov
2
0.50%
1
5.56%
al viro
al viro
1
0.25%
1
5.56%
Total
398
100.00%
18
100.00%



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;
}

Contributors
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pre-git
pre-git
398
69.82%
4
22.22%
marcin slusarz
marcin slusarz
54
9.47%
2
11.11%
linus torvalds
linus torvalds
48
8.42%
2
11.11%
jan kara
jan kara
31
5.44%
3
16.67%
ben fennema
ben fennema
29
5.09%
2
11.11%
al viro
al viro
7
1.23%
2
11.11%
pekka j enberg
pekka j enberg
2
0.35%
2
11.11%
andrew morton
andrew morton
1
0.18%
1
5.56%
Total
570
100.00%
18
100.00%



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;
}

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pre-git
pre-git
109
61.24%
3
25.00%
marcin slusarz
marcin slusarz
25
14.04%
3
25.00%
linus torvalds
linus torvalds
18
10.11%
2
16.67%
alessio igor bogani
alessio igor bogani
15
8.43%
1
8.33%
namjae jeon
namjae jeon
5
2.81%
1
8.33%
jan kara
jan kara
3
1.69%
1
8.33%
andrew morton
andrew morton
3
1.69%
1
8.33%
Total
178
100.00%
12
100.00%



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;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
pre-git
pre-git
115
82.14%
2
28.57%
linus torvalds
linus torvalds
18
12.86%
2
28.57%
cyrill gorcunov
cyrill gorcunov
5
3.57%
1
14.29%
andrew morton
andrew morton
1
0.71%
1
14.29%
andries brouwer
andries brouwer
1
0.71%
1
14.29%
Total
140
100.00%
7
100.00%

/* 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 {
		struct kernel_lb_addr tmploc;
		uint32_t tmplen;

		udf_write_aext(inode, last_pos, &last_ext->extLocation,
				last_ext->extLength, 1);
		/*
                 * We've rewritten the last extent but there may be empty
                 * indirect extent after it - enter it.
                 */
		udf_next_aext(inode, last_pos, &tmploc, &tmplen, 0);
	}

	/* 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