[linux.git] / fs / udf / truncate.c

/*
 * truncate.c
 *
 * PURPOSE
 *	Truncate 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) 1999-2004 Ben Fennema
 *  (C) 1999 Stelias Computing Inc
 *
 * HISTORY
 *
 *  02/24/99 blf  Created.
 *
 */

#include "udfdecl.h"
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/buffer_head.h>

#include "udf_i.h"
#include "udf_sb.h"

static void extent_trunc(struct inode *inode, struct extent_position *epos,
			 struct kernel_lb_addr *eloc, int8_t etype, uint32_t elen,
			 uint32_t nelen)
{
	struct kernel_lb_addr neloc = {};
	int last_block = (elen + inode->i_sb->s_blocksize - 1) >>
		inode->i_sb->s_blocksize_bits;
	int first_block = (nelen + inode->i_sb->s_blocksize - 1) >>
		inode->i_sb->s_blocksize_bits;

	if (nelen) {
		if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
			udf_free_blocks(inode->i_sb, inode, eloc, 0,
					last_block);
			etype = (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30);
		} else
			neloc = *eloc;
		nelen = (etype << 30) | nelen;
	}

	if (elen != nelen) {
		udf_write_aext(inode, epos, &neloc, nelen, 0);
		if (last_block - first_block > 0) {
			if (etype == (EXT_RECORDED_ALLOCATED >> 30))
				mark_inode_dirty(inode);

			if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
				udf_free_blocks(inode->i_sb, inode, eloc,
						first_block,
						last_block - first_block);
		}
	}
}

/*
 * Truncate the last extent to match i_size. This function assumes
 * that preallocation extent is already truncated.
 */
void udf_truncate_tail_extent(struct inode *inode)
{
	struct extent_position epos = {};
	struct kernel_lb_addr eloc;
	uint32_t elen, nelen;
	uint64_t lbcount = 0;
	int8_t etype = -1, netype;
	int adsize;
	struct udf_inode_info *iinfo = UDF_I(inode);

	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB ||
	    inode->i_size == iinfo->i_lenExtents)
		return;
	/* Are we going to delete the file anyway? */
	if (inode->i_nlink == 0)
		return;

	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();

	/* Find the last extent in the file */
	while ((netype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1) {
		etype = netype;
		lbcount += elen;
		if (lbcount > inode->i_size) {
			if (lbcount - inode->i_size >= inode->i_sb->s_blocksize)
				printk(KERN_WARNING
				       "udf_truncate_tail_extent(): Too long "
				       "extent after EOF in inode %u: i_size: "
				       "%Ld lbcount: %Ld extent %u+%u\n",
				       (unsigned)inode->i_ino,
				       (long long)inode->i_size,
				       (long long)lbcount,
				       (unsigned)eloc.logicalBlockNum,
				       (unsigned)elen);
			nelen = elen - (lbcount - inode->i_size);
			epos.offset -= adsize;
			extent_trunc(inode, &epos, &eloc, etype, elen, nelen);
			epos.offset += adsize;
			if (udf_next_aext(inode, &epos, &eloc, &elen, 1) != -1)
				printk(KERN_ERR "udf_truncate_tail_extent(): "
				       "Extent after EOF in inode %u.\n",
				       (unsigned)inode->i_ino);
			break;
		}
	}
	/* This inode entry is in-memory only and thus we don't have to mark
	 * the inode dirty */
	iinfo->i_lenExtents = inode->i_size;
	brelse(epos.bh);
}

void udf_discard_prealloc(struct inode *inode)
{
	struct extent_position epos = { NULL, 0, {0, 0} };
	struct kernel_lb_addr eloc;
	uint32_t elen;
	uint64_t lbcount = 0;
	int8_t etype = -1, netype;
	int adsize;
	struct udf_inode_info *iinfo = UDF_I(inode);

	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB ||
	    inode->i_size == iinfo->i_lenExtents)
		return;

	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;

	epos.block = iinfo->i_location;

	/* Find the last extent in the file */
	while ((netype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1) {
		etype = netype;
		lbcount += elen;
	}
	if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
		epos.offset -= adsize;
		lbcount -= elen;
		extent_trunc(inode, &epos, &eloc, etype, elen, 0);
		if (!epos.bh) {
			iinfo->i_lenAlloc =
				epos.offset -
				udf_file_entry_alloc_offset(inode);
			mark_inode_dirty(inode);
		} else {
			struct allocExtDesc *aed =
				(struct allocExtDesc *)(epos.bh->b_data);
			aed->lengthAllocDescs =
				cpu_to_le32(epos.offset -
					    sizeof(struct allocExtDesc));
			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);
			else
				udf_update_tag(epos.bh->b_data,
					       sizeof(struct allocExtDesc));
			mark_buffer_dirty_inode(epos.bh, inode);
		}
	}
	/* This inode entry is in-memory only and thus we don't have to mark
	 * the inode dirty */
	iinfo->i_lenExtents = lbcount;
	brelse(epos.bh);
}

static void udf_update_alloc_ext_desc(struct inode *inode,
				      struct extent_position *epos,
				      u32 lenalloc)
{
	struct super_block *sb = inode->i_sb;
	struct udf_sb_info *sbi = UDF_SB(sb);

	struct allocExtDesc *aed = (struct allocExtDesc *) (epos->bh->b_data);
	int len = sizeof(struct allocExtDesc);

	aed->lengthAllocDescs =	cpu_to_le32(lenalloc);
	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT) || sbi->s_udfrev >= 0x0201)
		len += lenalloc;

	udf_update_tag(epos->bh->b_data, len);
	mark_buffer_dirty_inode(epos->bh, inode);
}

void udf_truncate_extents(struct inode *inode)
{
	struct extent_position epos;
	struct kernel_lb_addr eloc, neloc = {};
	uint32_t elen, nelen = 0, indirect_ext_len = 0, lenalloc;
	int8_t etype;
	struct super_block *sb = inode->i_sb;
	sector_t first_block = inode->i_size >> sb->s_blocksize_bits, offset;
	loff_t byte_offset;
	int adsize;
	struct udf_inode_info *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
		BUG();

	etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset);
	byte_offset = (offset << sb->s_blocksize_bits) +
		(inode->i_size & (sb->s_blocksize - 1));
	if (etype != -1) {
		epos.offset -= adsize;
		extent_trunc(inode, &epos, &eloc, etype, elen, byte_offset);
		epos.offset += adsize;
		if (byte_offset)
			lenalloc = epos.offset;
		else
			lenalloc = epos.offset - adsize;

		if (!epos.bh)
			lenalloc -= udf_file_entry_alloc_offset(inode);
		else
			lenalloc -= sizeof(struct allocExtDesc);

		while ((etype = udf_current_aext(inode, &epos, &eloc,
						 &elen, 0)) != -1) {
			if (etype == (EXT_NEXT_EXTENT_ALLOCDECS >> 30)) {
				udf_write_aext(inode, &epos, &neloc, nelen, 0);
				if (indirect_ext_len) {
					/* We managed to free all extents in the
					 * indirect extent - free it too */
					BUG_ON(!epos.bh);
					udf_free_blocks(sb, inode, &epos.block,
							0, indirect_ext_len);
				} else if (!epos.bh) {
					iinfo->i_lenAlloc = lenalloc;
					mark_inode_dirty(inode);
				} else
					udf_update_alloc_ext_desc(inode,
							&epos, lenalloc);
				brelse(epos.bh);
				epos.offset = sizeof(struct allocExtDesc);
				epos.block = eloc;
				epos.bh = udf_tread(sb,
						udf_get_lb_pblock(sb, &eloc, 0));
				if (elen)
					indirect_ext_len =
						(elen + sb->s_blocksize - 1) >>
						sb->s_blocksize_bits;
				else
					indirect_ext_len = 1;
			} else {
				extent_trunc(inode, &epos, &eloc, etype,
					     elen, 0);
				epos.offset += adsize;
			}
		}

		if (indirect_ext_len) {
			BUG_ON(!epos.bh);
			udf_free_blocks(sb, inode, &epos.block, 0,
					indirect_ext_len);
		} else if (!epos.bh) {
			iinfo->i_lenAlloc = lenalloc;
			mark_inode_dirty(inode);
		} else
			udf_update_alloc_ext_desc(inode, &epos, lenalloc);
	} else if (inode->i_size) {
		if (byte_offset) {
			struct kernel_long_ad extent;

			/*
			 *  OK, there is not extent covering inode->i_size and
			 *  no extent above inode->i_size => 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;
			}
			udf_extend_file(inode, &epos, &extent,
					offset +
					((inode->i_size &
						(sb->s_blocksize - 1)) != 0));
		}
	}
	iinfo->i_lenExtents = inode->i_size;

	brelse(epos.bh);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* truncate.c
	3	*
	4	* PURPOSE
	5	* Truncate handling routines for the OSTA-UDF(tm) filesystem.
	6	*
1da177e4 LT	7	* COPYRIGHT
	8	* This file is distributed under the terms of the GNU General Public
	9	* License (GPL). Copies of the GPL can be obtained from:
	10	* ftp://prep.ai.mit.edu/pub/gnu/GPL
	11	* Each contributing author retains all rights to their own work.
	12	*
	13	* (C) 1999-2004 Ben Fennema
	14	* (C) 1999 Stelias Computing Inc
	15	*
	16	* HISTORY
	17	*
	18	* 02/24/99 blf Created.
	19	*
	20	*/
	21
	22	#include "udfdecl.h"
	23	#include <linux/fs.h>
	24	#include <linux/mm.h>
1da177e4 LT	25	#include <linux/buffer_head.h>
	26
	27	#include "udf_i.h"
	28	#include "udf_sb.h"
	29
cb00ea35	30	static void extent_trunc(struct inode inode, struct extent_position epos,
97e961fd	31	struct kernel_lb_addr *eloc, int8_t etype, uint32_t elen,
cb00ea35	32	uint32_t nelen)
1da177e4	33	{
5ca4e4be	34	struct kernel_lb_addr neloc = {};
28de7948 CG	35	int last_block = (elen + inode->i_sb->s_blocksize - 1) >>
	36	inode->i_sb->s_blocksize_bits;
	37	int first_block = (nelen + inode->i_sb->s_blocksize - 1) >>
	38	inode->i_sb->s_blocksize_bits;
1da177e4	39
cb00ea35 CG	40	if (nelen) {
	41	if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
	42	udf_free_blocks(inode->i_sb, inode, eloc, 0,
	43	last_block);
1da177e4	44	etype = (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30);
cb00ea35	45	} else
97e961fd	46	neloc = *eloc;
1da177e4 LT	47	nelen = (etype << 30) \| nelen;
	48	}
	49
cb00ea35	50	if (elen != nelen) {
97e961fd	51	udf_write_aext(inode, epos, &neloc, nelen, 0);
cb00ea35	52	if (last_block - first_block > 0) {
1da177e4 LT	53	if (etype == (EXT_RECORDED_ALLOCATED >> 30))
	54	mark_inode_dirty(inode);
	55
	56	if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
cb00ea35 CG	57	udf_free_blocks(inode->i_sb, inode, eloc,
	58	first_block,
	59	last_block - first_block);
1da177e4 LT	60	}
	61	}
	62	}
	63
74584ae5 JK	64	/*
	65	* Truncate the last extent to match i_size. This function assumes
	66	* that preallocation extent is already truncated.
	67	*/
	68	void udf_truncate_tail_extent(struct inode *inode)
1da177e4	69	{
28de7948	70	struct extent_position epos = {};
5ca4e4be	71	struct kernel_lb_addr eloc;
ff116fc8	72	uint32_t elen, nelen;
1da177e4 LT	73	uint64_t lbcount = 0;
1da177e4 LT	74	int8_t etype = -1, netype;
1da177e4	75	int adsize;
48d6d8ff	76	struct udf_inode_info *iinfo = UDF_I(inode);
1da177e4	77
48d6d8ff MS	78	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB \|\|
48d6d8ff MS	79	inode->i_size == iinfo->i_lenExtents)
74584ae5 JK	80	return;
	81	/* Are we going to delete the file anyway? */
	82	if (inode->i_nlink == 0)
1da177e4	83	return;
1da177e4	84
48d6d8ff	85	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
5ca4e4be	86	adsize = sizeof(struct short_ad);
48d6d8ff	87	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
5ca4e4be	88	adsize = sizeof(struct long_ad);
1da177e4	89	else
74584ae5	90	BUG();
1da177e4	91
ff116fc8	92	/* Find the last extent in the file */
cb00ea35	93	while ((netype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1) {
1da177e4 LT	94	etype = netype;
1da177e4 LT	95	lbcount += elen;
74584ae5 JK	96	if (lbcount > inode->i_size) {
	97	if (lbcount - inode->i_size >= inode->i_sb->s_blocksize)
	98	printk(KERN_WARNING
	99	"udf_truncate_tail_extent(): Too long "
	100	"extent after EOF in inode %u: i_size: "
	101	"%Ld lbcount: %Ld extent %u+%u\n",
	102	(unsigned)inode->i_ino,
	103	(long long)inode->i_size,
	104	(long long)lbcount,
	105	(unsigned)eloc.logicalBlockNum,
	106	(unsigned)elen);
1da177e4	107	nelen = elen - (lbcount - inode->i_size);
ff116fc8	108	epos.offset -= adsize;
97e961fd	109	extent_trunc(inode, &epos, &eloc, etype, elen, nelen);
ff116fc8	110	epos.offset += adsize;
74584ae5 JK	111	if (udf_next_aext(inode, &epos, &eloc, &elen, 1) != -1)
	112	printk(KERN_ERR "udf_truncate_tail_extent(): "
	113	"Extent after EOF in inode %u.\n",
	114	(unsigned)inode->i_ino);
	115	break;
1da177e4 LT	116	}
1da177e4 LT	117	}
74584ae5 JK	118	/* This inode entry is in-memory only and thus we don't have to mark
74584ae5 JK	119	* the inode dirty */
48d6d8ff	120	iinfo->i_lenExtents = inode->i_size;
74584ae5 JK	121	brelse(epos.bh);
	122	}
	123
	124	void udf_discard_prealloc(struct inode *inode)
	125	{
cb00ea35	126	struct extent_position epos = { NULL, 0, {0, 0} };
5ca4e4be	127	struct kernel_lb_addr eloc;
74584ae5 JK	128	uint32_t elen;
	129	uint64_t lbcount = 0;
	130	int8_t etype = -1, netype;
	131	int adsize;
48d6d8ff	132	struct udf_inode_info *iinfo = UDF_I(inode);
74584ae5	133
48d6d8ff MS	134	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB \|\|
48d6d8ff MS	135	inode->i_size == iinfo->i_lenExtents)
74584ae5 JK	136	return;
74584ae5 JK	137
48d6d8ff	138	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
5ca4e4be	139	adsize = sizeof(struct short_ad);
48d6d8ff	140	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
5ca4e4be	141	adsize = sizeof(struct long_ad);
74584ae5 JK	142	else
	143	adsize = 0;
	144
48d6d8ff	145	epos.block = iinfo->i_location;
74584ae5 JK	146
	147	/* Find the last extent in the file */
	148	while ((netype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1) {
	149	etype = netype;
	150	lbcount += elen;
	151	}
ff116fc8 JK	152	if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
ff116fc8 JK	153	epos.offset -= adsize;
1da177e4	154	lbcount -= elen;
97e961fd	155	extent_trunc(inode, &epos, &eloc, etype, elen, 0);
74584ae5	156	if (!epos.bh) {
48d6d8ff	157	iinfo->i_lenAlloc =
4b11111a MS	158	epos.offset -
4b11111a MS	159	udf_file_entry_alloc_offset(inode);
1da177e4	160	mark_inode_dirty(inode);
74584ae5	161	} else {
cb00ea35	162	struct allocExtDesc *aed =
28de7948	163	(struct allocExtDesc *)(epos.bh->b_data);
cb00ea35	164	aed->lengthAllocDescs =
28de7948 CG	165	cpu_to_le32(epos.offset -
	166	sizeof(struct allocExtDesc));
	167	if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) \|\|
6c79e987	168	UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
ff116fc8	169	udf_update_tag(epos.bh->b_data, epos.offset);
1da177e4	170	else
cb00ea35 CG	171	udf_update_tag(epos.bh->b_data,
cb00ea35 CG	172	sizeof(struct allocExtDesc));
ff116fc8	173	mark_buffer_dirty_inode(epos.bh, inode);
1da177e4 LT	174	}
1da177e4 LT	175	}
74584ae5 JK	176	/* This inode entry is in-memory only and thus we don't have to mark
74584ae5 JK	177	* the inode dirty */
48d6d8ff	178	iinfo->i_lenExtents = lbcount;
3bf25cb4	179	brelse(epos.bh);
1da177e4 LT	180	}
1da177e4 LT	181
456390de	182	static void udf_update_alloc_ext_desc(struct inode *inode,
	183	struct extent_position *epos,
	184	u32 lenalloc)
	185	{
	186	struct super_block *sb = inode->i_sb;
	187	struct udf_sb_info *sbi = UDF_SB(sb);
	188
	189	struct allocExtDesc aed = (struct allocExtDesc ) (epos->bh->b_data);
	190	int len = sizeof(struct allocExtDesc);
	191
	192	aed->lengthAllocDescs = cpu_to_le32(lenalloc);
	193	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT) \|\| sbi->s_udfrev >= 0x0201)
	194	len += lenalloc;
	195
	196	udf_update_tag(epos->bh->b_data, len);
	197	mark_buffer_dirty_inode(epos->bh, inode);
	198	}
	199
cb00ea35	200	void udf_truncate_extents(struct inode *inode)
1da177e4	201	{
ff116fc8	202	struct extent_position epos;
5ca4e4be	203	struct kernel_lb_addr eloc, neloc = {};
ff116fc8	204	uint32_t elen, nelen = 0, indirect_ext_len = 0, lenalloc;
1da177e4	205	int8_t etype;
31170b6a JK	206	struct super_block *sb = inode->i_sb;
31170b6a JK	207	sector_t first_block = inode->i_size >> sb->s_blocksize_bits, offset;
60448b1d	208	loff_t byte_offset;
1da177e4	209	int adsize;
48d6d8ff	210	struct udf_inode_info *iinfo = UDF_I(inode);
1da177e4	211
48d6d8ff	212	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
5ca4e4be	213	adsize = sizeof(struct short_ad);
48d6d8ff	214	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
5ca4e4be	215	adsize = sizeof(struct long_ad);
1da177e4	216	else
ff116fc8	217	BUG();
1da177e4	218
ff116fc8	219	etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset);
28de7948 CG	220	byte_offset = (offset << sb->s_blocksize_bits) +
28de7948 CG	221	(inode->i_size & (sb->s_blocksize - 1));
cb00ea35	222	if (etype != -1) {
ff116fc8	223	epos.offset -= adsize;
97e961fd	224	extent_trunc(inode, &epos, &eloc, etype, elen, byte_offset);
ff116fc8	225	epos.offset += adsize;
60448b1d	226	if (byte_offset)
ff116fc8	227	lenalloc = epos.offset;
1da177e4	228	else
ff116fc8	229	lenalloc = epos.offset - adsize;
1da177e4	230
ff116fc8	231	if (!epos.bh)
1da177e4 LT	232	lenalloc -= udf_file_entry_alloc_offset(inode);
	233	else
	234	lenalloc -= sizeof(struct allocExtDesc);
	235
4b11111a MS	236	while ((etype = udf_current_aext(inode, &epos, &eloc,
4b11111a MS	237	&elen, 0)) != -1) {
cb00ea35	238	if (etype == (EXT_NEXT_EXTENT_ALLOCDECS >> 30)) {
97e961fd	239	udf_write_aext(inode, &epos, &neloc, nelen, 0);
cb00ea35	240	if (indirect_ext_len) {
ff116fc8 JK	241	/* We managed to free all extents in the
ff116fc8 JK	242	* indirect extent - free it too */
9de90b76	243	BUG_ON(!epos.bh);
97e961fd	244	udf_free_blocks(sb, inode, &epos.block,
cb00ea35	245	0, indirect_ext_len);
9de90b76	246	} else if (!epos.bh) {
	247	iinfo->i_lenAlloc = lenalloc;
	248	mark_inode_dirty(inode);
456390de	249	} else
	250	udf_update_alloc_ext_desc(inode,
	251	&epos, lenalloc);
ff116fc8 JK	252	brelse(epos.bh);
	253	epos.offset = sizeof(struct allocExtDesc);
	254	epos.block = eloc;
4b11111a	255	epos.bh = udf_tread(sb,
97e961fd	256	udf_get_lb_pblock(sb, &eloc, 0));
1da177e4	257	if (elen)
4b11111a MS	258	indirect_ext_len =
4b11111a MS	259	(elen + sb->s_blocksize - 1) >>
28de7948	260	sb->s_blocksize_bits;
1da177e4	261	else
ff116fc8	262	indirect_ext_len = 1;
cb00ea35	263	} else {
97e961fd	264	extent_trunc(inode, &epos, &eloc, etype,
4b11111a	265	elen, 0);
ff116fc8	266	epos.offset += adsize;
1da177e4 LT	267	}
	268	}
	269
cb00ea35	270	if (indirect_ext_len) {
9de90b76	271	BUG_ON(!epos.bh);
97e961fd	272	udf_free_blocks(sb, inode, &epos.block, 0,
cb00ea35	273	indirect_ext_len);
9de90b76	274	} else if (!epos.bh) {
	275	iinfo->i_lenAlloc = lenalloc;
	276	mark_inode_dirty(inode);
456390de	277	} else
456390de	278	udf_update_alloc_ext_desc(inode, &epos, lenalloc);
cb00ea35 CG	279	} else if (inode->i_size) {
cb00ea35 CG	280	if (byte_offset) {
5ca4e4be	281	struct kernel_long_ad extent;
31170b6a	282
00a2b0f6 JK	283	/*
	284	* OK, there is not extent covering inode->i_size and
	285	* no extent above inode->i_size => truncate is
31170b6a	286	* extending the file by 'offset' blocks.
00a2b0f6	287	*/
28de7948	288	if ((!epos.bh &&
4b11111a MS	289	epos.offset ==
	290	udf_file_entry_alloc_offset(inode)) \|\|
	291	(epos.bh && epos.offset ==
	292	sizeof(struct allocExtDesc))) {
31170b6a JK	293	/* File has no extents at all or has empty last
	294	* indirect extent! Create a fake extent... */
	295	extent.extLocation.logicalBlockNum = 0;
	296	extent.extLocation.partitionReferenceNum = 0;
4b11111a MS	297	extent.extLength =
4b11111a MS	298	EXT_NOT_RECORDED_NOT_ALLOCATED;
cb00ea35	299	} else {
ff116fc8	300	epos.offset -= adsize;
31170b6a	301	etype = udf_next_aext(inode, &epos,
cb00ea35 CG	302	&extent.extLocation,
cb00ea35 CG	303	&extent.extLength, 0);
31170b6a	304	extent.extLength \|= etype << 30;
1da177e4	305	}
cb00ea35	306	udf_extend_file(inode, &epos, &extent,
4b11111a MS	307	offset +
	308	((inode->i_size &
	309	(sb->s_blocksize - 1)) != 0));
1da177e4 LT	310	}
1da177e4 LT	311	}
48d6d8ff	312	iinfo->i_lenExtents = inode->i_size;
1da177e4	313
3bf25cb4	314	brelse(epos.bh);
1da177e4	315	}