xref: /openbmc/linux/fs/udf/inode.c (revision 2359ccdd)
1 /*
2  * inode.c
3  *
4  * PURPOSE
5  *  Inode handling routines for the OSTA-UDF(tm) filesystem.
6  *
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) 1998 Dave Boynton
14  *  (C) 1998-2004 Ben Fennema
15  *  (C) 1999-2000 Stelias Computing Inc
16  *
17  * HISTORY
18  *
19  *  10/04/98 dgb  Added rudimentary directory functions
20  *  10/07/98      Fully working udf_block_map! It works!
21  *  11/25/98      bmap altered to better support extents
22  *  12/06/98 blf  partition support in udf_iget, udf_block_map
23  *                and udf_read_inode
24  *  12/12/98      rewrote udf_block_map to handle next extents and descs across
25  *                block boundaries (which is not actually allowed)
26  *  12/20/98      added support for strategy 4096
27  *  03/07/99      rewrote udf_block_map (again)
28  *                New funcs, inode_bmap, udf_next_aext
29  *  04/19/99      Support for writing device EA's for major/minor #
30  */
31 
32 #include "udfdecl.h"
33 #include <linux/mm.h>
34 #include <linux/module.h>
35 #include <linux/pagemap.h>
36 #include <linux/writeback.h>
37 #include <linux/slab.h>
38 #include <linux/crc-itu-t.h>
39 #include <linux/mpage.h>
40 #include <linux/uio.h>
41 #include <linux/bio.h>
42 
43 #include "udf_i.h"
44 #include "udf_sb.h"
45 
46 #define EXTENT_MERGE_SIZE 5
47 
48 static umode_t udf_convert_permissions(struct fileEntry *);
49 static int udf_update_inode(struct inode *, int);
50 static int udf_sync_inode(struct inode *inode);
51 static int udf_alloc_i_data(struct inode *inode, size_t size);
52 static sector_t inode_getblk(struct inode *, sector_t, int *, int *);
53 static int8_t udf_insert_aext(struct inode *, struct extent_position,
54 			      struct kernel_lb_addr, uint32_t);
55 static void udf_split_extents(struct inode *, int *, int, udf_pblk_t,
56 			      struct kernel_long_ad *, int *);
57 static void udf_prealloc_extents(struct inode *, int, int,
58 				 struct kernel_long_ad *, int *);
59 static void udf_merge_extents(struct inode *, struct kernel_long_ad *, int *);
60 static void udf_update_extents(struct inode *, struct kernel_long_ad *, int,
61 			       int, struct extent_position *);
62 static int udf_get_block(struct inode *, sector_t, struct buffer_head *, int);
63 
64 static void __udf_clear_extent_cache(struct inode *inode)
65 {
66 	struct udf_inode_info *iinfo = UDF_I(inode);
67 
68 	if (iinfo->cached_extent.lstart != -1) {
69 		brelse(iinfo->cached_extent.epos.bh);
70 		iinfo->cached_extent.lstart = -1;
71 	}
72 }
73 
74 /* Invalidate extent cache */
75 static void udf_clear_extent_cache(struct inode *inode)
76 {
77 	struct udf_inode_info *iinfo = UDF_I(inode);
78 
79 	spin_lock(&iinfo->i_extent_cache_lock);
80 	__udf_clear_extent_cache(inode);
81 	spin_unlock(&iinfo->i_extent_cache_lock);
82 }
83 
84 /* Return contents of extent cache */
85 static int udf_read_extent_cache(struct inode *inode, loff_t bcount,
86 				 loff_t *lbcount, struct extent_position *pos)
87 {
88 	struct udf_inode_info *iinfo = UDF_I(inode);
89 	int ret = 0;
90 
91 	spin_lock(&iinfo->i_extent_cache_lock);
92 	if ((iinfo->cached_extent.lstart <= bcount) &&
93 	    (iinfo->cached_extent.lstart != -1)) {
94 		/* Cache hit */
95 		*lbcount = iinfo->cached_extent.lstart;
96 		memcpy(pos, &iinfo->cached_extent.epos,
97 		       sizeof(struct extent_position));
98 		if (pos->bh)
99 			get_bh(pos->bh);
100 		ret = 1;
101 	}
102 	spin_unlock(&iinfo->i_extent_cache_lock);
103 	return ret;
104 }
105 
106 /* Add extent to extent cache */
107 static void udf_update_extent_cache(struct inode *inode, loff_t estart,
108 				    struct extent_position *pos)
109 {
110 	struct udf_inode_info *iinfo = UDF_I(inode);
111 
112 	spin_lock(&iinfo->i_extent_cache_lock);
113 	/* Invalidate previously cached extent */
114 	__udf_clear_extent_cache(inode);
115 	if (pos->bh)
116 		get_bh(pos->bh);
117 	memcpy(&iinfo->cached_extent.epos, pos, sizeof(*pos));
118 	iinfo->cached_extent.lstart = estart;
119 	switch (iinfo->i_alloc_type) {
120 	case ICBTAG_FLAG_AD_SHORT:
121 		iinfo->cached_extent.epos.offset -= sizeof(struct short_ad);
122 		break;
123 	case ICBTAG_FLAG_AD_LONG:
124 		iinfo->cached_extent.epos.offset -= sizeof(struct long_ad);
125 		break;
126 	}
127 	spin_unlock(&iinfo->i_extent_cache_lock);
128 }
129 
130 void udf_evict_inode(struct inode *inode)
131 {
132 	struct udf_inode_info *iinfo = UDF_I(inode);
133 	int want_delete = 0;
134 
135 	if (!inode->i_nlink && !is_bad_inode(inode)) {
136 		want_delete = 1;
137 		udf_setsize(inode, 0);
138 		udf_update_inode(inode, IS_SYNC(inode));
139 	}
140 	truncate_inode_pages_final(&inode->i_data);
141 	invalidate_inode_buffers(inode);
142 	clear_inode(inode);
143 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB &&
144 	    inode->i_size != iinfo->i_lenExtents) {
145 		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",
146 			 inode->i_ino, inode->i_mode,
147 			 (unsigned long long)inode->i_size,
148 			 (unsigned long long)iinfo->i_lenExtents);
149 	}
150 	kfree(iinfo->i_ext.i_data);
151 	iinfo->i_ext.i_data = NULL;
152 	udf_clear_extent_cache(inode);
153 	if (want_delete) {
154 		udf_free_inode(inode);
155 	}
156 }
157 
158 static void udf_write_failed(struct address_space *mapping, loff_t to)
159 {
160 	struct inode *inode = mapping->host;
161 	struct udf_inode_info *iinfo = UDF_I(inode);
162 	loff_t isize = inode->i_size;
163 
164 	if (to > isize) {
165 		truncate_pagecache(inode, isize);
166 		if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
167 			down_write(&iinfo->i_data_sem);
168 			udf_clear_extent_cache(inode);
169 			udf_truncate_extents(inode);
170 			up_write(&iinfo->i_data_sem);
171 		}
172 	}
173 }
174 
175 static int udf_writepage(struct page *page, struct writeback_control *wbc)
176 {
177 	return block_write_full_page(page, udf_get_block, wbc);
178 }
179 
180 static int udf_writepages(struct address_space *mapping,
181 			struct writeback_control *wbc)
182 {
183 	return mpage_writepages(mapping, wbc, udf_get_block);
184 }
185 
186 static int udf_readpage(struct file *file, struct page *page)
187 {
188 	return mpage_readpage(page, udf_get_block);
189 }
190 
191 static int udf_readpages(struct file *file, struct address_space *mapping,
192 			struct list_head *pages, unsigned nr_pages)
193 {
194 	return mpage_readpages(mapping, pages, nr_pages, udf_get_block);
195 }
196 
197 static int udf_write_begin(struct file *file, struct address_space *mapping,
198 			loff_t pos, unsigned len, unsigned flags,
199 			struct page **pagep, void **fsdata)
200 {
201 	int ret;
202 
203 	ret = block_write_begin(mapping, pos, len, flags, pagep, udf_get_block);
204 	if (unlikely(ret))
205 		udf_write_failed(mapping, pos + len);
206 	return ret;
207 }
208 
209 static ssize_t udf_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
210 {
211 	struct file *file = iocb->ki_filp;
212 	struct address_space *mapping = file->f_mapping;
213 	struct inode *inode = mapping->host;
214 	size_t count = iov_iter_count(iter);
215 	ssize_t ret;
216 
217 	ret = blockdev_direct_IO(iocb, inode, iter, udf_get_block);
218 	if (unlikely(ret < 0 && iov_iter_rw(iter) == WRITE))
219 		udf_write_failed(mapping, iocb->ki_pos + count);
220 	return ret;
221 }
222 
223 static sector_t udf_bmap(struct address_space *mapping, sector_t block)
224 {
225 	return generic_block_bmap(mapping, block, udf_get_block);
226 }
227 
228 const struct address_space_operations udf_aops = {
229 	.readpage	= udf_readpage,
230 	.readpages	= udf_readpages,
231 	.writepage	= udf_writepage,
232 	.writepages	= udf_writepages,
233 	.write_begin	= udf_write_begin,
234 	.write_end	= generic_write_end,
235 	.direct_IO	= udf_direct_IO,
236 	.bmap		= udf_bmap,
237 };
238 
239 /*
240  * Expand file stored in ICB to a normal one-block-file
241  *
242  * This function requires i_data_sem for writing and releases it.
243  * This function requires i_mutex held
244  */
245 int udf_expand_file_adinicb(struct inode *inode)
246 {
247 	struct page *page;
248 	char *kaddr;
249 	struct udf_inode_info *iinfo = UDF_I(inode);
250 	int err;
251 	struct writeback_control udf_wbc = {
252 		.sync_mode = WB_SYNC_NONE,
253 		.nr_to_write = 1,
254 	};
255 
256 	WARN_ON_ONCE(!inode_is_locked(inode));
257 	if (!iinfo->i_lenAlloc) {
258 		if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
259 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
260 		else
261 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
262 		/* from now on we have normal address_space methods */
263 		inode->i_data.a_ops = &udf_aops;
264 		up_write(&iinfo->i_data_sem);
265 		mark_inode_dirty(inode);
266 		return 0;
267 	}
268 	/*
269 	 * Release i_data_sem so that we can lock a page - page lock ranks
270 	 * above i_data_sem. i_mutex still protects us against file changes.
271 	 */
272 	up_write(&iinfo->i_data_sem);
273 
274 	page = find_or_create_page(inode->i_mapping, 0, GFP_NOFS);
275 	if (!page)
276 		return -ENOMEM;
277 
278 	if (!PageUptodate(page)) {
279 		kaddr = kmap_atomic(page);
280 		memset(kaddr + iinfo->i_lenAlloc, 0x00,
281 		       PAGE_SIZE - iinfo->i_lenAlloc);
282 		memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr,
283 			iinfo->i_lenAlloc);
284 		flush_dcache_page(page);
285 		SetPageUptodate(page);
286 		kunmap_atomic(kaddr);
287 	}
288 	down_write(&iinfo->i_data_sem);
289 	memset(iinfo->i_ext.i_data + iinfo->i_lenEAttr, 0x00,
290 	       iinfo->i_lenAlloc);
291 	iinfo->i_lenAlloc = 0;
292 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
293 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
294 	else
295 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
296 	/* from now on we have normal address_space methods */
297 	inode->i_data.a_ops = &udf_aops;
298 	up_write(&iinfo->i_data_sem);
299 	err = inode->i_data.a_ops->writepage(page, &udf_wbc);
300 	if (err) {
301 		/* Restore everything back so that we don't lose data... */
302 		lock_page(page);
303 		down_write(&iinfo->i_data_sem);
304 		kaddr = kmap_atomic(page);
305 		memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr, kaddr,
306 		       inode->i_size);
307 		kunmap_atomic(kaddr);
308 		unlock_page(page);
309 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
310 		inode->i_data.a_ops = &udf_adinicb_aops;
311 		up_write(&iinfo->i_data_sem);
312 	}
313 	put_page(page);
314 	mark_inode_dirty(inode);
315 
316 	return err;
317 }
318 
319 struct buffer_head *udf_expand_dir_adinicb(struct inode *inode,
320 					    udf_pblk_t *block, int *err)
321 {
322 	udf_pblk_t newblock;
323 	struct buffer_head *dbh = NULL;
324 	struct kernel_lb_addr eloc;
325 	uint8_t alloctype;
326 	struct extent_position epos;
327 
328 	struct udf_fileident_bh sfibh, dfibh;
329 	loff_t f_pos = udf_ext0_offset(inode);
330 	int size = udf_ext0_offset(inode) + inode->i_size;
331 	struct fileIdentDesc cfi, *sfi, *dfi;
332 	struct udf_inode_info *iinfo = UDF_I(inode);
333 
334 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
335 		alloctype = ICBTAG_FLAG_AD_SHORT;
336 	else
337 		alloctype = ICBTAG_FLAG_AD_LONG;
338 
339 	if (!inode->i_size) {
340 		iinfo->i_alloc_type = alloctype;
341 		mark_inode_dirty(inode);
342 		return NULL;
343 	}
344 
345 	/* alloc block, and copy data to it */
346 	*block = udf_new_block(inode->i_sb, inode,
347 			       iinfo->i_location.partitionReferenceNum,
348 			       iinfo->i_location.logicalBlockNum, err);
349 	if (!(*block))
350 		return NULL;
351 	newblock = udf_get_pblock(inode->i_sb, *block,
352 				  iinfo->i_location.partitionReferenceNum,
353 				0);
354 	if (!newblock)
355 		return NULL;
356 	dbh = udf_tgetblk(inode->i_sb, newblock);
357 	if (!dbh)
358 		return NULL;
359 	lock_buffer(dbh);
360 	memset(dbh->b_data, 0x00, inode->i_sb->s_blocksize);
361 	set_buffer_uptodate(dbh);
362 	unlock_buffer(dbh);
363 	mark_buffer_dirty_inode(dbh, inode);
364 
365 	sfibh.soffset = sfibh.eoffset =
366 			f_pos & (inode->i_sb->s_blocksize - 1);
367 	sfibh.sbh = sfibh.ebh = NULL;
368 	dfibh.soffset = dfibh.eoffset = 0;
369 	dfibh.sbh = dfibh.ebh = dbh;
370 	while (f_pos < size) {
371 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
372 		sfi = udf_fileident_read(inode, &f_pos, &sfibh, &cfi, NULL,
373 					 NULL, NULL, NULL);
374 		if (!sfi) {
375 			brelse(dbh);
376 			return NULL;
377 		}
378 		iinfo->i_alloc_type = alloctype;
379 		sfi->descTag.tagLocation = cpu_to_le32(*block);
380 		dfibh.soffset = dfibh.eoffset;
381 		dfibh.eoffset += (sfibh.eoffset - sfibh.soffset);
382 		dfi = (struct fileIdentDesc *)(dbh->b_data + dfibh.soffset);
383 		if (udf_write_fi(inode, sfi, dfi, &dfibh, sfi->impUse,
384 				 sfi->fileIdent +
385 					le16_to_cpu(sfi->lengthOfImpUse))) {
386 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
387 			brelse(dbh);
388 			return NULL;
389 		}
390 	}
391 	mark_buffer_dirty_inode(dbh, inode);
392 
393 	memset(iinfo->i_ext.i_data + iinfo->i_lenEAttr, 0,
394 		iinfo->i_lenAlloc);
395 	iinfo->i_lenAlloc = 0;
396 	eloc.logicalBlockNum = *block;
397 	eloc.partitionReferenceNum =
398 				iinfo->i_location.partitionReferenceNum;
399 	iinfo->i_lenExtents = inode->i_size;
400 	epos.bh = NULL;
401 	epos.block = iinfo->i_location;
402 	epos.offset = udf_file_entry_alloc_offset(inode);
403 	udf_add_aext(inode, &epos, &eloc, inode->i_size, 0);
404 	/* UniqueID stuff */
405 
406 	brelse(epos.bh);
407 	mark_inode_dirty(inode);
408 	return dbh;
409 }
410 
411 static int udf_get_block(struct inode *inode, sector_t block,
412 			 struct buffer_head *bh_result, int create)
413 {
414 	int err, new;
415 	sector_t phys = 0;
416 	struct udf_inode_info *iinfo;
417 
418 	if (!create) {
419 		phys = udf_block_map(inode, block);
420 		if (phys)
421 			map_bh(bh_result, inode->i_sb, phys);
422 		return 0;
423 	}
424 
425 	err = -EIO;
426 	new = 0;
427 	iinfo = UDF_I(inode);
428 
429 	down_write(&iinfo->i_data_sem);
430 	if (block == iinfo->i_next_alloc_block + 1) {
431 		iinfo->i_next_alloc_block++;
432 		iinfo->i_next_alloc_goal++;
433 	}
434 
435 	udf_clear_extent_cache(inode);
436 	phys = inode_getblk(inode, block, &err, &new);
437 	if (!phys)
438 		goto abort;
439 
440 	if (new)
441 		set_buffer_new(bh_result);
442 	map_bh(bh_result, inode->i_sb, phys);
443 
444 abort:
445 	up_write(&iinfo->i_data_sem);
446 	return err;
447 }
448 
449 static struct buffer_head *udf_getblk(struct inode *inode, udf_pblk_t block,
450 				      int create, int *err)
451 {
452 	struct buffer_head *bh;
453 	struct buffer_head dummy;
454 
455 	dummy.b_state = 0;
456 	dummy.b_blocknr = -1000;
457 	*err = udf_get_block(inode, block, &dummy, create);
458 	if (!*err && buffer_mapped(&dummy)) {
459 		bh = sb_getblk(inode->i_sb, dummy.b_blocknr);
460 		if (buffer_new(&dummy)) {
461 			lock_buffer(bh);
462 			memset(bh->b_data, 0x00, inode->i_sb->s_blocksize);
463 			set_buffer_uptodate(bh);
464 			unlock_buffer(bh);
465 			mark_buffer_dirty_inode(bh, inode);
466 		}
467 		return bh;
468 	}
469 
470 	return NULL;
471 }
472 
473 /* Extend the file by 'blocks' blocks, return the number of extents added */
474 static int udf_do_extend_file(struct inode *inode,
475 			      struct extent_position *last_pos,
476 			      struct kernel_long_ad *last_ext,
477 			      sector_t blocks)
478 {
479 	sector_t add;
480 	int count = 0, fake = !(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
481 	struct super_block *sb = inode->i_sb;
482 	struct kernel_lb_addr prealloc_loc = {};
483 	uint32_t prealloc_len = 0;
484 	struct udf_inode_info *iinfo;
485 	int err;
486 
487 	/* The previous extent is fake and we should not extend by anything
488 	 * - there's nothing to do... */
489 	if (!blocks && fake)
490 		return 0;
491 
492 	iinfo = UDF_I(inode);
493 	/* Round the last extent up to a multiple of block size */
494 	if (last_ext->extLength & (sb->s_blocksize - 1)) {
495 		last_ext->extLength =
496 			(last_ext->extLength & UDF_EXTENT_FLAG_MASK) |
497 			(((last_ext->extLength & UDF_EXTENT_LENGTH_MASK) +
498 			  sb->s_blocksize - 1) & ~(sb->s_blocksize - 1));
499 		iinfo->i_lenExtents =
500 			(iinfo->i_lenExtents + sb->s_blocksize - 1) &
501 			~(sb->s_blocksize - 1);
502 	}
503 
504 	/* Last extent are just preallocated blocks? */
505 	if ((last_ext->extLength & UDF_EXTENT_FLAG_MASK) ==
506 						EXT_NOT_RECORDED_ALLOCATED) {
507 		/* Save the extent so that we can reattach it to the end */
508 		prealloc_loc = last_ext->extLocation;
509 		prealloc_len = last_ext->extLength;
510 		/* Mark the extent as a hole */
511 		last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
512 			(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
513 		last_ext->extLocation.logicalBlockNum = 0;
514 		last_ext->extLocation.partitionReferenceNum = 0;
515 	}
516 
517 	/* Can we merge with the previous extent? */
518 	if ((last_ext->extLength & UDF_EXTENT_FLAG_MASK) ==
519 					EXT_NOT_RECORDED_NOT_ALLOCATED) {
520 		add = ((1 << 30) - sb->s_blocksize -
521 			(last_ext->extLength & UDF_EXTENT_LENGTH_MASK)) >>
522 			sb->s_blocksize_bits;
523 		if (add > blocks)
524 			add = blocks;
525 		blocks -= add;
526 		last_ext->extLength += add << sb->s_blocksize_bits;
527 	}
528 
529 	if (fake) {
530 		udf_add_aext(inode, last_pos, &last_ext->extLocation,
531 			     last_ext->extLength, 1);
532 		count++;
533 	} else {
534 		struct kernel_lb_addr tmploc;
535 		uint32_t tmplen;
536 
537 		udf_write_aext(inode, last_pos, &last_ext->extLocation,
538 				last_ext->extLength, 1);
539 		/*
540 		 * We've rewritten the last extent but there may be empty
541 		 * indirect extent after it - enter it.
542 		 */
543 		udf_next_aext(inode, last_pos, &tmploc, &tmplen, 0);
544 	}
545 
546 	/* Managed to do everything necessary? */
547 	if (!blocks)
548 		goto out;
549 
550 	/* All further extents will be NOT_RECORDED_NOT_ALLOCATED */
551 	last_ext->extLocation.logicalBlockNum = 0;
552 	last_ext->extLocation.partitionReferenceNum = 0;
553 	add = (1 << (30-sb->s_blocksize_bits)) - 1;
554 	last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
555 				(add << sb->s_blocksize_bits);
556 
557 	/* Create enough extents to cover the whole hole */
558 	while (blocks > add) {
559 		blocks -= add;
560 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
561 				   last_ext->extLength, 1);
562 		if (err)
563 			return err;
564 		count++;
565 	}
566 	if (blocks) {
567 		last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
568 			(blocks << sb->s_blocksize_bits);
569 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
570 				   last_ext->extLength, 1);
571 		if (err)
572 			return err;
573 		count++;
574 	}
575 
576 out:
577 	/* Do we have some preallocated blocks saved? */
578 	if (prealloc_len) {
579 		err = udf_add_aext(inode, last_pos, &prealloc_loc,
580 				   prealloc_len, 1);
581 		if (err)
582 			return err;
583 		last_ext->extLocation = prealloc_loc;
584 		last_ext->extLength = prealloc_len;
585 		count++;
586 	}
587 
588 	/* last_pos should point to the last written extent... */
589 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
590 		last_pos->offset -= sizeof(struct short_ad);
591 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
592 		last_pos->offset -= sizeof(struct long_ad);
593 	else
594 		return -EIO;
595 
596 	return count;
597 }
598 
599 static int udf_extend_file(struct inode *inode, loff_t newsize)
600 {
601 
602 	struct extent_position epos;
603 	struct kernel_lb_addr eloc;
604 	uint32_t elen;
605 	int8_t etype;
606 	struct super_block *sb = inode->i_sb;
607 	sector_t first_block = newsize >> sb->s_blocksize_bits, offset;
608 	int adsize;
609 	struct udf_inode_info *iinfo = UDF_I(inode);
610 	struct kernel_long_ad extent;
611 	int err;
612 
613 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
614 		adsize = sizeof(struct short_ad);
615 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
616 		adsize = sizeof(struct long_ad);
617 	else
618 		BUG();
619 
620 	etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset);
621 
622 	/* File has extent covering the new size (could happen when extending
623 	 * inside a block)? */
624 	if (etype != -1)
625 		return 0;
626 	if (newsize & (sb->s_blocksize - 1))
627 		offset++;
628 	/* Extended file just to the boundary of the last file block? */
629 	if (offset == 0)
630 		return 0;
631 
632 	/* Truncate is extending the file by 'offset' blocks */
633 	if ((!epos.bh && epos.offset == udf_file_entry_alloc_offset(inode)) ||
634 	    (epos.bh && epos.offset == sizeof(struct allocExtDesc))) {
635 		/* File has no extents at all or has empty last
636 		 * indirect extent! Create a fake extent... */
637 		extent.extLocation.logicalBlockNum = 0;
638 		extent.extLocation.partitionReferenceNum = 0;
639 		extent.extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
640 	} else {
641 		epos.offset -= adsize;
642 		etype = udf_next_aext(inode, &epos, &extent.extLocation,
643 				      &extent.extLength, 0);
644 		extent.extLength |= etype << 30;
645 	}
646 	err = udf_do_extend_file(inode, &epos, &extent, offset);
647 	if (err < 0)
648 		goto out;
649 	err = 0;
650 	iinfo->i_lenExtents = newsize;
651 out:
652 	brelse(epos.bh);
653 	return err;
654 }
655 
656 static sector_t inode_getblk(struct inode *inode, sector_t block,
657 			     int *err, int *new)
658 {
659 	struct kernel_long_ad laarr[EXTENT_MERGE_SIZE];
660 	struct extent_position prev_epos, cur_epos, next_epos;
661 	int count = 0, startnum = 0, endnum = 0;
662 	uint32_t elen = 0, tmpelen;
663 	struct kernel_lb_addr eloc, tmpeloc;
664 	int c = 1;
665 	loff_t lbcount = 0, b_off = 0;
666 	udf_pblk_t newblocknum, newblock;
667 	sector_t offset = 0;
668 	int8_t etype;
669 	struct udf_inode_info *iinfo = UDF_I(inode);
670 	udf_pblk_t goal = 0, pgoal = iinfo->i_location.logicalBlockNum;
671 	int lastblock = 0;
672 	bool isBeyondEOF;
673 
674 	*err = 0;
675 	*new = 0;
676 	prev_epos.offset = udf_file_entry_alloc_offset(inode);
677 	prev_epos.block = iinfo->i_location;
678 	prev_epos.bh = NULL;
679 	cur_epos = next_epos = prev_epos;
680 	b_off = (loff_t)block << inode->i_sb->s_blocksize_bits;
681 
682 	/* find the extent which contains the block we are looking for.
683 	   alternate between laarr[0] and laarr[1] for locations of the
684 	   current extent, and the previous extent */
685 	do {
686 		if (prev_epos.bh != cur_epos.bh) {
687 			brelse(prev_epos.bh);
688 			get_bh(cur_epos.bh);
689 			prev_epos.bh = cur_epos.bh;
690 		}
691 		if (cur_epos.bh != next_epos.bh) {
692 			brelse(cur_epos.bh);
693 			get_bh(next_epos.bh);
694 			cur_epos.bh = next_epos.bh;
695 		}
696 
697 		lbcount += elen;
698 
699 		prev_epos.block = cur_epos.block;
700 		cur_epos.block = next_epos.block;
701 
702 		prev_epos.offset = cur_epos.offset;
703 		cur_epos.offset = next_epos.offset;
704 
705 		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 1);
706 		if (etype == -1)
707 			break;
708 
709 		c = !c;
710 
711 		laarr[c].extLength = (etype << 30) | elen;
712 		laarr[c].extLocation = eloc;
713 
714 		if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
715 			pgoal = eloc.logicalBlockNum +
716 				((elen + inode->i_sb->s_blocksize - 1) >>
717 				 inode->i_sb->s_blocksize_bits);
718 
719 		count++;
720 	} while (lbcount + elen <= b_off);
721 
722 	b_off -= lbcount;
723 	offset = b_off >> inode->i_sb->s_blocksize_bits;
724 	/*
725 	 * Move prev_epos and cur_epos into indirect extent if we are at
726 	 * the pointer to it
727 	 */
728 	udf_next_aext(inode, &prev_epos, &tmpeloc, &tmpelen, 0);
729 	udf_next_aext(inode, &cur_epos, &tmpeloc, &tmpelen, 0);
730 
731 	/* if the extent is allocated and recorded, return the block
732 	   if the extent is not a multiple of the blocksize, round up */
733 
734 	if (etype == (EXT_RECORDED_ALLOCATED >> 30)) {
735 		if (elen & (inode->i_sb->s_blocksize - 1)) {
736 			elen = EXT_RECORDED_ALLOCATED |
737 				((elen + inode->i_sb->s_blocksize - 1) &
738 				 ~(inode->i_sb->s_blocksize - 1));
739 			udf_write_aext(inode, &cur_epos, &eloc, elen, 1);
740 		}
741 		newblock = udf_get_lb_pblock(inode->i_sb, &eloc, offset);
742 		goto out_free;
743 	}
744 
745 	/* Are we beyond EOF? */
746 	if (etype == -1) {
747 		int ret;
748 		isBeyondEOF = true;
749 		if (count) {
750 			if (c)
751 				laarr[0] = laarr[1];
752 			startnum = 1;
753 		} else {
754 			/* Create a fake extent when there's not one */
755 			memset(&laarr[0].extLocation, 0x00,
756 				sizeof(struct kernel_lb_addr));
757 			laarr[0].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
758 			/* Will udf_do_extend_file() create real extent from
759 			   a fake one? */
760 			startnum = (offset > 0);
761 		}
762 		/* Create extents for the hole between EOF and offset */
763 		ret = udf_do_extend_file(inode, &prev_epos, laarr, offset);
764 		if (ret < 0) {
765 			*err = ret;
766 			newblock = 0;
767 			goto out_free;
768 		}
769 		c = 0;
770 		offset = 0;
771 		count += ret;
772 		/* We are not covered by a preallocated extent? */
773 		if ((laarr[0].extLength & UDF_EXTENT_FLAG_MASK) !=
774 						EXT_NOT_RECORDED_ALLOCATED) {
775 			/* Is there any real extent? - otherwise we overwrite
776 			 * the fake one... */
777 			if (count)
778 				c = !c;
779 			laarr[c].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
780 				inode->i_sb->s_blocksize;
781 			memset(&laarr[c].extLocation, 0x00,
782 				sizeof(struct kernel_lb_addr));
783 			count++;
784 		}
785 		endnum = c + 1;
786 		lastblock = 1;
787 	} else {
788 		isBeyondEOF = false;
789 		endnum = startnum = ((count > 2) ? 2 : count);
790 
791 		/* if the current extent is in position 0,
792 		   swap it with the previous */
793 		if (!c && count != 1) {
794 			laarr[2] = laarr[0];
795 			laarr[0] = laarr[1];
796 			laarr[1] = laarr[2];
797 			c = 1;
798 		}
799 
800 		/* if the current block is located in an extent,
801 		   read the next extent */
802 		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 0);
803 		if (etype != -1) {
804 			laarr[c + 1].extLength = (etype << 30) | elen;
805 			laarr[c + 1].extLocation = eloc;
806 			count++;
807 			startnum++;
808 			endnum++;
809 		} else
810 			lastblock = 1;
811 	}
812 
813 	/* if the current extent is not recorded but allocated, get the
814 	 * block in the extent corresponding to the requested block */
815 	if ((laarr[c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30))
816 		newblocknum = laarr[c].extLocation.logicalBlockNum + offset;
817 	else { /* otherwise, allocate a new block */
818 		if (iinfo->i_next_alloc_block == block)
819 			goal = iinfo->i_next_alloc_goal;
820 
821 		if (!goal) {
822 			if (!(goal = pgoal)) /* XXX: what was intended here? */
823 				goal = iinfo->i_location.logicalBlockNum + 1;
824 		}
825 
826 		newblocknum = udf_new_block(inode->i_sb, inode,
827 				iinfo->i_location.partitionReferenceNum,
828 				goal, err);
829 		if (!newblocknum) {
830 			*err = -ENOSPC;
831 			newblock = 0;
832 			goto out_free;
833 		}
834 		if (isBeyondEOF)
835 			iinfo->i_lenExtents += inode->i_sb->s_blocksize;
836 	}
837 
838 	/* if the extent the requsted block is located in contains multiple
839 	 * blocks, split the extent into at most three extents. blocks prior
840 	 * to requested block, requested block, and blocks after requested
841 	 * block */
842 	udf_split_extents(inode, &c, offset, newblocknum, laarr, &endnum);
843 
844 	/* We preallocate blocks only for regular files. It also makes sense
845 	 * for directories but there's a problem when to drop the
846 	 * preallocation. We might use some delayed work for that but I feel
847 	 * it's overengineering for a filesystem like UDF. */
848 	if (S_ISREG(inode->i_mode))
849 		udf_prealloc_extents(inode, c, lastblock, laarr, &endnum);
850 
851 	/* merge any continuous blocks in laarr */
852 	udf_merge_extents(inode, laarr, &endnum);
853 
854 	/* write back the new extents, inserting new extents if the new number
855 	 * of extents is greater than the old number, and deleting extents if
856 	 * the new number of extents is less than the old number */
857 	udf_update_extents(inode, laarr, startnum, endnum, &prev_epos);
858 
859 	newblock = udf_get_pblock(inode->i_sb, newblocknum,
860 				iinfo->i_location.partitionReferenceNum, 0);
861 	if (!newblock) {
862 		*err = -EIO;
863 		goto out_free;
864 	}
865 	*new = 1;
866 	iinfo->i_next_alloc_block = block;
867 	iinfo->i_next_alloc_goal = newblocknum;
868 	inode->i_ctime = current_time(inode);
869 
870 	if (IS_SYNC(inode))
871 		udf_sync_inode(inode);
872 	else
873 		mark_inode_dirty(inode);
874 out_free:
875 	brelse(prev_epos.bh);
876 	brelse(cur_epos.bh);
877 	brelse(next_epos.bh);
878 	return newblock;
879 }
880 
881 static void udf_split_extents(struct inode *inode, int *c, int offset,
882 			       udf_pblk_t newblocknum,
883 			       struct kernel_long_ad *laarr, int *endnum)
884 {
885 	unsigned long blocksize = inode->i_sb->s_blocksize;
886 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
887 
888 	if ((laarr[*c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30) ||
889 	    (laarr[*c].extLength >> 30) ==
890 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
891 		int curr = *c;
892 		int blen = ((laarr[curr].extLength & UDF_EXTENT_LENGTH_MASK) +
893 			    blocksize - 1) >> blocksize_bits;
894 		int8_t etype = (laarr[curr].extLength >> 30);
895 
896 		if (blen == 1)
897 			;
898 		else if (!offset || blen == offset + 1) {
899 			laarr[curr + 2] = laarr[curr + 1];
900 			laarr[curr + 1] = laarr[curr];
901 		} else {
902 			laarr[curr + 3] = laarr[curr + 1];
903 			laarr[curr + 2] = laarr[curr + 1] = laarr[curr];
904 		}
905 
906 		if (offset) {
907 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
908 				udf_free_blocks(inode->i_sb, inode,
909 						&laarr[curr].extLocation,
910 						0, offset);
911 				laarr[curr].extLength =
912 					EXT_NOT_RECORDED_NOT_ALLOCATED |
913 					(offset << blocksize_bits);
914 				laarr[curr].extLocation.logicalBlockNum = 0;
915 				laarr[curr].extLocation.
916 						partitionReferenceNum = 0;
917 			} else
918 				laarr[curr].extLength = (etype << 30) |
919 					(offset << blocksize_bits);
920 			curr++;
921 			(*c)++;
922 			(*endnum)++;
923 		}
924 
925 		laarr[curr].extLocation.logicalBlockNum = newblocknum;
926 		if (etype == (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
927 			laarr[curr].extLocation.partitionReferenceNum =
928 				UDF_I(inode)->i_location.partitionReferenceNum;
929 		laarr[curr].extLength = EXT_RECORDED_ALLOCATED |
930 			blocksize;
931 		curr++;
932 
933 		if (blen != offset + 1) {
934 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
935 				laarr[curr].extLocation.logicalBlockNum +=
936 								offset + 1;
937 			laarr[curr].extLength = (etype << 30) |
938 				((blen - (offset + 1)) << blocksize_bits);
939 			curr++;
940 			(*endnum)++;
941 		}
942 	}
943 }
944 
945 static void udf_prealloc_extents(struct inode *inode, int c, int lastblock,
946 				 struct kernel_long_ad *laarr,
947 				 int *endnum)
948 {
949 	int start, length = 0, currlength = 0, i;
950 
951 	if (*endnum >= (c + 1)) {
952 		if (!lastblock)
953 			return;
954 		else
955 			start = c;
956 	} else {
957 		if ((laarr[c + 1].extLength >> 30) ==
958 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
959 			start = c + 1;
960 			length = currlength =
961 				(((laarr[c + 1].extLength &
962 					UDF_EXTENT_LENGTH_MASK) +
963 				inode->i_sb->s_blocksize - 1) >>
964 				inode->i_sb->s_blocksize_bits);
965 		} else
966 			start = c;
967 	}
968 
969 	for (i = start + 1; i <= *endnum; i++) {
970 		if (i == *endnum) {
971 			if (lastblock)
972 				length += UDF_DEFAULT_PREALLOC_BLOCKS;
973 		} else if ((laarr[i].extLength >> 30) ==
974 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
975 			length += (((laarr[i].extLength &
976 						UDF_EXTENT_LENGTH_MASK) +
977 				    inode->i_sb->s_blocksize - 1) >>
978 				    inode->i_sb->s_blocksize_bits);
979 		} else
980 			break;
981 	}
982 
983 	if (length) {
984 		int next = laarr[start].extLocation.logicalBlockNum +
985 			(((laarr[start].extLength & UDF_EXTENT_LENGTH_MASK) +
986 			  inode->i_sb->s_blocksize - 1) >>
987 			  inode->i_sb->s_blocksize_bits);
988 		int numalloc = udf_prealloc_blocks(inode->i_sb, inode,
989 				laarr[start].extLocation.partitionReferenceNum,
990 				next, (UDF_DEFAULT_PREALLOC_BLOCKS > length ?
991 				length : UDF_DEFAULT_PREALLOC_BLOCKS) -
992 				currlength);
993 		if (numalloc) 	{
994 			if (start == (c + 1))
995 				laarr[start].extLength +=
996 					(numalloc <<
997 					 inode->i_sb->s_blocksize_bits);
998 			else {
999 				memmove(&laarr[c + 2], &laarr[c + 1],
1000 					sizeof(struct long_ad) * (*endnum - (c + 1)));
1001 				(*endnum)++;
1002 				laarr[c + 1].extLocation.logicalBlockNum = next;
1003 				laarr[c + 1].extLocation.partitionReferenceNum =
1004 					laarr[c].extLocation.
1005 							partitionReferenceNum;
1006 				laarr[c + 1].extLength =
1007 					EXT_NOT_RECORDED_ALLOCATED |
1008 					(numalloc <<
1009 					 inode->i_sb->s_blocksize_bits);
1010 				start = c + 1;
1011 			}
1012 
1013 			for (i = start + 1; numalloc && i < *endnum; i++) {
1014 				int elen = ((laarr[i].extLength &
1015 						UDF_EXTENT_LENGTH_MASK) +
1016 					    inode->i_sb->s_blocksize - 1) >>
1017 					    inode->i_sb->s_blocksize_bits;
1018 
1019 				if (elen > numalloc) {
1020 					laarr[i].extLength -=
1021 						(numalloc <<
1022 						 inode->i_sb->s_blocksize_bits);
1023 					numalloc = 0;
1024 				} else {
1025 					numalloc -= elen;
1026 					if (*endnum > (i + 1))
1027 						memmove(&laarr[i],
1028 							&laarr[i + 1],
1029 							sizeof(struct long_ad) *
1030 							(*endnum - (i + 1)));
1031 					i--;
1032 					(*endnum)--;
1033 				}
1034 			}
1035 			UDF_I(inode)->i_lenExtents +=
1036 				numalloc << inode->i_sb->s_blocksize_bits;
1037 		}
1038 	}
1039 }
1040 
1041 static void udf_merge_extents(struct inode *inode, struct kernel_long_ad *laarr,
1042 			      int *endnum)
1043 {
1044 	int i;
1045 	unsigned long blocksize = inode->i_sb->s_blocksize;
1046 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1047 
1048 	for (i = 0; i < (*endnum - 1); i++) {
1049 		struct kernel_long_ad *li /*l[i]*/ = &laarr[i];
1050 		struct kernel_long_ad *lip1 /*l[i plus 1]*/ = &laarr[i + 1];
1051 
1052 		if (((li->extLength >> 30) == (lip1->extLength >> 30)) &&
1053 			(((li->extLength >> 30) ==
1054 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) ||
1055 			((lip1->extLocation.logicalBlockNum -
1056 			  li->extLocation.logicalBlockNum) ==
1057 			(((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1058 			blocksize - 1) >> blocksize_bits)))) {
1059 
1060 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1061 				(lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1062 				blocksize - 1) & ~UDF_EXTENT_LENGTH_MASK) {
1063 				lip1->extLength = (lip1->extLength -
1064 						  (li->extLength &
1065 						   UDF_EXTENT_LENGTH_MASK) +
1066 						   UDF_EXTENT_LENGTH_MASK) &
1067 							~(blocksize - 1);
1068 				li->extLength = (li->extLength &
1069 						 UDF_EXTENT_FLAG_MASK) +
1070 						(UDF_EXTENT_LENGTH_MASK + 1) -
1071 						blocksize;
1072 				lip1->extLocation.logicalBlockNum =
1073 					li->extLocation.logicalBlockNum +
1074 					((li->extLength &
1075 						UDF_EXTENT_LENGTH_MASK) >>
1076 						blocksize_bits);
1077 			} else {
1078 				li->extLength = lip1->extLength +
1079 					(((li->extLength &
1080 						UDF_EXTENT_LENGTH_MASK) +
1081 					 blocksize - 1) & ~(blocksize - 1));
1082 				if (*endnum > (i + 2))
1083 					memmove(&laarr[i + 1], &laarr[i + 2],
1084 						sizeof(struct long_ad) *
1085 						(*endnum - (i + 2)));
1086 				i--;
1087 				(*endnum)--;
1088 			}
1089 		} else if (((li->extLength >> 30) ==
1090 				(EXT_NOT_RECORDED_ALLOCATED >> 30)) &&
1091 			   ((lip1->extLength >> 30) ==
1092 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))) {
1093 			udf_free_blocks(inode->i_sb, inode, &li->extLocation, 0,
1094 					((li->extLength &
1095 					  UDF_EXTENT_LENGTH_MASK) +
1096 					 blocksize - 1) >> blocksize_bits);
1097 			li->extLocation.logicalBlockNum = 0;
1098 			li->extLocation.partitionReferenceNum = 0;
1099 
1100 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1101 			     (lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1102 			     blocksize - 1) & ~UDF_EXTENT_LENGTH_MASK) {
1103 				lip1->extLength = (lip1->extLength -
1104 						   (li->extLength &
1105 						   UDF_EXTENT_LENGTH_MASK) +
1106 						   UDF_EXTENT_LENGTH_MASK) &
1107 						   ~(blocksize - 1);
1108 				li->extLength = (li->extLength &
1109 						 UDF_EXTENT_FLAG_MASK) +
1110 						(UDF_EXTENT_LENGTH_MASK + 1) -
1111 						blocksize;
1112 			} else {
1113 				li->extLength = lip1->extLength +
1114 					(((li->extLength &
1115 						UDF_EXTENT_LENGTH_MASK) +
1116 					  blocksize - 1) & ~(blocksize - 1));
1117 				if (*endnum > (i + 2))
1118 					memmove(&laarr[i + 1], &laarr[i + 2],
1119 						sizeof(struct long_ad) *
1120 						(*endnum - (i + 2)));
1121 				i--;
1122 				(*endnum)--;
1123 			}
1124 		} else if ((li->extLength >> 30) ==
1125 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
1126 			udf_free_blocks(inode->i_sb, inode,
1127 					&li->extLocation, 0,
1128 					((li->extLength &
1129 						UDF_EXTENT_LENGTH_MASK) +
1130 					 blocksize - 1) >> blocksize_bits);
1131 			li->extLocation.logicalBlockNum = 0;
1132 			li->extLocation.partitionReferenceNum = 0;
1133 			li->extLength = (li->extLength &
1134 						UDF_EXTENT_LENGTH_MASK) |
1135 						EXT_NOT_RECORDED_NOT_ALLOCATED;
1136 		}
1137 	}
1138 }
1139 
1140 static void udf_update_extents(struct inode *inode, struct kernel_long_ad *laarr,
1141 			       int startnum, int endnum,
1142 			       struct extent_position *epos)
1143 {
1144 	int start = 0, i;
1145 	struct kernel_lb_addr tmploc;
1146 	uint32_t tmplen;
1147 
1148 	if (startnum > endnum) {
1149 		for (i = 0; i < (startnum - endnum); i++)
1150 			udf_delete_aext(inode, *epos, laarr[i].extLocation,
1151 					laarr[i].extLength);
1152 	} else if (startnum < endnum) {
1153 		for (i = 0; i < (endnum - startnum); i++) {
1154 			udf_insert_aext(inode, *epos, laarr[i].extLocation,
1155 					laarr[i].extLength);
1156 			udf_next_aext(inode, epos, &laarr[i].extLocation,
1157 				      &laarr[i].extLength, 1);
1158 			start++;
1159 		}
1160 	}
1161 
1162 	for (i = start; i < endnum; i++) {
1163 		udf_next_aext(inode, epos, &tmploc, &tmplen, 0);
1164 		udf_write_aext(inode, epos, &laarr[i].extLocation,
1165 			       laarr[i].extLength, 1);
1166 	}
1167 }
1168 
1169 struct buffer_head *udf_bread(struct inode *inode, udf_pblk_t block,
1170 			      int create, int *err)
1171 {
1172 	struct buffer_head *bh = NULL;
1173 
1174 	bh = udf_getblk(inode, block, create, err);
1175 	if (!bh)
1176 		return NULL;
1177 
1178 	if (buffer_uptodate(bh))
1179 		return bh;
1180 
1181 	ll_rw_block(REQ_OP_READ, 0, 1, &bh);
1182 
1183 	wait_on_buffer(bh);
1184 	if (buffer_uptodate(bh))
1185 		return bh;
1186 
1187 	brelse(bh);
1188 	*err = -EIO;
1189 	return NULL;
1190 }
1191 
1192 int udf_setsize(struct inode *inode, loff_t newsize)
1193 {
1194 	int err;
1195 	struct udf_inode_info *iinfo;
1196 	unsigned int bsize = i_blocksize(inode);
1197 
1198 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1199 	      S_ISLNK(inode->i_mode)))
1200 		return -EINVAL;
1201 	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
1202 		return -EPERM;
1203 
1204 	iinfo = UDF_I(inode);
1205 	if (newsize > inode->i_size) {
1206 		down_write(&iinfo->i_data_sem);
1207 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1208 			if (bsize <
1209 			    (udf_file_entry_alloc_offset(inode) + newsize)) {
1210 				err = udf_expand_file_adinicb(inode);
1211 				if (err)
1212 					return err;
1213 				down_write(&iinfo->i_data_sem);
1214 			} else {
1215 				iinfo->i_lenAlloc = newsize;
1216 				goto set_size;
1217 			}
1218 		}
1219 		err = udf_extend_file(inode, newsize);
1220 		if (err) {
1221 			up_write(&iinfo->i_data_sem);
1222 			return err;
1223 		}
1224 set_size:
1225 		up_write(&iinfo->i_data_sem);
1226 		truncate_setsize(inode, newsize);
1227 	} else {
1228 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1229 			down_write(&iinfo->i_data_sem);
1230 			udf_clear_extent_cache(inode);
1231 			memset(iinfo->i_ext.i_data + iinfo->i_lenEAttr + newsize,
1232 			       0x00, bsize - newsize -
1233 			       udf_file_entry_alloc_offset(inode));
1234 			iinfo->i_lenAlloc = newsize;
1235 			truncate_setsize(inode, newsize);
1236 			up_write(&iinfo->i_data_sem);
1237 			goto update_time;
1238 		}
1239 		err = block_truncate_page(inode->i_mapping, newsize,
1240 					  udf_get_block);
1241 		if (err)
1242 			return err;
1243 		truncate_setsize(inode, newsize);
1244 		down_write(&iinfo->i_data_sem);
1245 		udf_clear_extent_cache(inode);
1246 		udf_truncate_extents(inode);
1247 		up_write(&iinfo->i_data_sem);
1248 	}
1249 update_time:
1250 	inode->i_mtime = inode->i_ctime = current_time(inode);
1251 	if (IS_SYNC(inode))
1252 		udf_sync_inode(inode);
1253 	else
1254 		mark_inode_dirty(inode);
1255 	return 0;
1256 }
1257 
1258 /*
1259  * Maximum length of linked list formed by ICB hierarchy. The chosen number is
1260  * arbitrary - just that we hopefully don't limit any real use of rewritten
1261  * inode on write-once media but avoid looping for too long on corrupted media.
1262  */
1263 #define UDF_MAX_ICB_NESTING 1024
1264 
1265 static int udf_read_inode(struct inode *inode, bool hidden_inode)
1266 {
1267 	struct buffer_head *bh = NULL;
1268 	struct fileEntry *fe;
1269 	struct extendedFileEntry *efe;
1270 	uint16_t ident;
1271 	struct udf_inode_info *iinfo = UDF_I(inode);
1272 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1273 	struct kernel_lb_addr *iloc = &iinfo->i_location;
1274 	unsigned int link_count;
1275 	unsigned int indirections = 0;
1276 	int bs = inode->i_sb->s_blocksize;
1277 	int ret = -EIO;
1278 	uint32_t uid, gid;
1279 
1280 reread:
1281 	if (iloc->partitionReferenceNum >= sbi->s_partitions) {
1282 		udf_debug("partition reference: %u > logical volume partitions: %u\n",
1283 			  iloc->partitionReferenceNum, sbi->s_partitions);
1284 		return -EIO;
1285 	}
1286 
1287 	if (iloc->logicalBlockNum >=
1288 	    sbi->s_partmaps[iloc->partitionReferenceNum].s_partition_len) {
1289 		udf_debug("block=%u, partition=%u out of range\n",
1290 			  iloc->logicalBlockNum, iloc->partitionReferenceNum);
1291 		return -EIO;
1292 	}
1293 
1294 	/*
1295 	 * Set defaults, but the inode is still incomplete!
1296 	 * Note: get_new_inode() sets the following on a new inode:
1297 	 *      i_sb = sb
1298 	 *      i_no = ino
1299 	 *      i_flags = sb->s_flags
1300 	 *      i_state = 0
1301 	 * clean_inode(): zero fills and sets
1302 	 *      i_count = 1
1303 	 *      i_nlink = 1
1304 	 *      i_op = NULL;
1305 	 */
1306 	bh = udf_read_ptagged(inode->i_sb, iloc, 0, &ident);
1307 	if (!bh) {
1308 		udf_err(inode->i_sb, "(ino %lu) failed !bh\n", inode->i_ino);
1309 		return -EIO;
1310 	}
1311 
1312 	if (ident != TAG_IDENT_FE && ident != TAG_IDENT_EFE &&
1313 	    ident != TAG_IDENT_USE) {
1314 		udf_err(inode->i_sb, "(ino %lu) failed ident=%u\n",
1315 			inode->i_ino, ident);
1316 		goto out;
1317 	}
1318 
1319 	fe = (struct fileEntry *)bh->b_data;
1320 	efe = (struct extendedFileEntry *)bh->b_data;
1321 
1322 	if (fe->icbTag.strategyType == cpu_to_le16(4096)) {
1323 		struct buffer_head *ibh;
1324 
1325 		ibh = udf_read_ptagged(inode->i_sb, iloc, 1, &ident);
1326 		if (ident == TAG_IDENT_IE && ibh) {
1327 			struct kernel_lb_addr loc;
1328 			struct indirectEntry *ie;
1329 
1330 			ie = (struct indirectEntry *)ibh->b_data;
1331 			loc = lelb_to_cpu(ie->indirectICB.extLocation);
1332 
1333 			if (ie->indirectICB.extLength) {
1334 				brelse(ibh);
1335 				memcpy(&iinfo->i_location, &loc,
1336 				       sizeof(struct kernel_lb_addr));
1337 				if (++indirections > UDF_MAX_ICB_NESTING) {
1338 					udf_err(inode->i_sb,
1339 						"too many ICBs in ICB hierarchy"
1340 						" (max %d supported)\n",
1341 						UDF_MAX_ICB_NESTING);
1342 					goto out;
1343 				}
1344 				brelse(bh);
1345 				goto reread;
1346 			}
1347 		}
1348 		brelse(ibh);
1349 	} else if (fe->icbTag.strategyType != cpu_to_le16(4)) {
1350 		udf_err(inode->i_sb, "unsupported strategy type: %u\n",
1351 			le16_to_cpu(fe->icbTag.strategyType));
1352 		goto out;
1353 	}
1354 	if (fe->icbTag.strategyType == cpu_to_le16(4))
1355 		iinfo->i_strat4096 = 0;
1356 	else /* if (fe->icbTag.strategyType == cpu_to_le16(4096)) */
1357 		iinfo->i_strat4096 = 1;
1358 
1359 	iinfo->i_alloc_type = le16_to_cpu(fe->icbTag.flags) &
1360 							ICBTAG_FLAG_AD_MASK;
1361 	iinfo->i_unique = 0;
1362 	iinfo->i_lenEAttr = 0;
1363 	iinfo->i_lenExtents = 0;
1364 	iinfo->i_lenAlloc = 0;
1365 	iinfo->i_next_alloc_block = 0;
1366 	iinfo->i_next_alloc_goal = 0;
1367 	if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_EFE)) {
1368 		iinfo->i_efe = 1;
1369 		iinfo->i_use = 0;
1370 		ret = udf_alloc_i_data(inode, bs -
1371 					sizeof(struct extendedFileEntry));
1372 		if (ret)
1373 			goto out;
1374 		memcpy(iinfo->i_ext.i_data,
1375 		       bh->b_data + sizeof(struct extendedFileEntry),
1376 		       bs - sizeof(struct extendedFileEntry));
1377 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_FE)) {
1378 		iinfo->i_efe = 0;
1379 		iinfo->i_use = 0;
1380 		ret = udf_alloc_i_data(inode, bs - sizeof(struct fileEntry));
1381 		if (ret)
1382 			goto out;
1383 		memcpy(iinfo->i_ext.i_data,
1384 		       bh->b_data + sizeof(struct fileEntry),
1385 		       bs - sizeof(struct fileEntry));
1386 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_USE)) {
1387 		iinfo->i_efe = 0;
1388 		iinfo->i_use = 1;
1389 		iinfo->i_lenAlloc = le32_to_cpu(
1390 				((struct unallocSpaceEntry *)bh->b_data)->
1391 				 lengthAllocDescs);
1392 		ret = udf_alloc_i_data(inode, bs -
1393 					sizeof(struct unallocSpaceEntry));
1394 		if (ret)
1395 			goto out;
1396 		memcpy(iinfo->i_ext.i_data,
1397 		       bh->b_data + sizeof(struct unallocSpaceEntry),
1398 		       bs - sizeof(struct unallocSpaceEntry));
1399 		return 0;
1400 	}
1401 
1402 	ret = -EIO;
1403 	read_lock(&sbi->s_cred_lock);
1404 	uid = le32_to_cpu(fe->uid);
1405 	if (uid == UDF_INVALID_ID ||
1406 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_SET))
1407 		inode->i_uid = sbi->s_uid;
1408 	else
1409 		i_uid_write(inode, uid);
1410 
1411 	gid = le32_to_cpu(fe->gid);
1412 	if (gid == UDF_INVALID_ID ||
1413 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_SET))
1414 		inode->i_gid = sbi->s_gid;
1415 	else
1416 		i_gid_write(inode, gid);
1417 
1418 	if (fe->icbTag.fileType != ICBTAG_FILE_TYPE_DIRECTORY &&
1419 			sbi->s_fmode != UDF_INVALID_MODE)
1420 		inode->i_mode = sbi->s_fmode;
1421 	else if (fe->icbTag.fileType == ICBTAG_FILE_TYPE_DIRECTORY &&
1422 			sbi->s_dmode != UDF_INVALID_MODE)
1423 		inode->i_mode = sbi->s_dmode;
1424 	else
1425 		inode->i_mode = udf_convert_permissions(fe);
1426 	inode->i_mode &= ~sbi->s_umask;
1427 	read_unlock(&sbi->s_cred_lock);
1428 
1429 	link_count = le16_to_cpu(fe->fileLinkCount);
1430 	if (!link_count) {
1431 		if (!hidden_inode) {
1432 			ret = -ESTALE;
1433 			goto out;
1434 		}
1435 		link_count = 1;
1436 	}
1437 	set_nlink(inode, link_count);
1438 
1439 	inode->i_size = le64_to_cpu(fe->informationLength);
1440 	iinfo->i_lenExtents = inode->i_size;
1441 
1442 	if (iinfo->i_efe == 0) {
1443 		inode->i_blocks = le64_to_cpu(fe->logicalBlocksRecorded) <<
1444 			(inode->i_sb->s_blocksize_bits - 9);
1445 
1446 		if (!udf_disk_stamp_to_time(&inode->i_atime, fe->accessTime))
1447 			inode->i_atime = sbi->s_record_time;
1448 
1449 		if (!udf_disk_stamp_to_time(&inode->i_mtime,
1450 					    fe->modificationTime))
1451 			inode->i_mtime = sbi->s_record_time;
1452 
1453 		if (!udf_disk_stamp_to_time(&inode->i_ctime, fe->attrTime))
1454 			inode->i_ctime = sbi->s_record_time;
1455 
1456 		iinfo->i_unique = le64_to_cpu(fe->uniqueID);
1457 		iinfo->i_lenEAttr = le32_to_cpu(fe->lengthExtendedAttr);
1458 		iinfo->i_lenAlloc = le32_to_cpu(fe->lengthAllocDescs);
1459 		iinfo->i_checkpoint = le32_to_cpu(fe->checkpoint);
1460 	} else {
1461 		inode->i_blocks = le64_to_cpu(efe->logicalBlocksRecorded) <<
1462 		    (inode->i_sb->s_blocksize_bits - 9);
1463 
1464 		if (!udf_disk_stamp_to_time(&inode->i_atime, efe->accessTime))
1465 			inode->i_atime = sbi->s_record_time;
1466 
1467 		if (!udf_disk_stamp_to_time(&inode->i_mtime,
1468 					    efe->modificationTime))
1469 			inode->i_mtime = sbi->s_record_time;
1470 
1471 		if (!udf_disk_stamp_to_time(&iinfo->i_crtime, efe->createTime))
1472 			iinfo->i_crtime = sbi->s_record_time;
1473 
1474 		if (!udf_disk_stamp_to_time(&inode->i_ctime, efe->attrTime))
1475 			inode->i_ctime = sbi->s_record_time;
1476 
1477 		iinfo->i_unique = le64_to_cpu(efe->uniqueID);
1478 		iinfo->i_lenEAttr = le32_to_cpu(efe->lengthExtendedAttr);
1479 		iinfo->i_lenAlloc = le32_to_cpu(efe->lengthAllocDescs);
1480 		iinfo->i_checkpoint = le32_to_cpu(efe->checkpoint);
1481 	}
1482 	inode->i_generation = iinfo->i_unique;
1483 
1484 	/*
1485 	 * Sanity check length of allocation descriptors and extended attrs to
1486 	 * avoid integer overflows
1487 	 */
1488 	if (iinfo->i_lenEAttr > bs || iinfo->i_lenAlloc > bs)
1489 		goto out;
1490 	/* Now do exact checks */
1491 	if (udf_file_entry_alloc_offset(inode) + iinfo->i_lenAlloc > bs)
1492 		goto out;
1493 	/* Sanity checks for files in ICB so that we don't get confused later */
1494 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1495 		/*
1496 		 * For file in ICB data is stored in allocation descriptor
1497 		 * so sizes should match
1498 		 */
1499 		if (iinfo->i_lenAlloc != inode->i_size)
1500 			goto out;
1501 		/* File in ICB has to fit in there... */
1502 		if (inode->i_size > bs - udf_file_entry_alloc_offset(inode))
1503 			goto out;
1504 	}
1505 
1506 	switch (fe->icbTag.fileType) {
1507 	case ICBTAG_FILE_TYPE_DIRECTORY:
1508 		inode->i_op = &udf_dir_inode_operations;
1509 		inode->i_fop = &udf_dir_operations;
1510 		inode->i_mode |= S_IFDIR;
1511 		inc_nlink(inode);
1512 		break;
1513 	case ICBTAG_FILE_TYPE_REALTIME:
1514 	case ICBTAG_FILE_TYPE_REGULAR:
1515 	case ICBTAG_FILE_TYPE_UNDEF:
1516 	case ICBTAG_FILE_TYPE_VAT20:
1517 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1518 			inode->i_data.a_ops = &udf_adinicb_aops;
1519 		else
1520 			inode->i_data.a_ops = &udf_aops;
1521 		inode->i_op = &udf_file_inode_operations;
1522 		inode->i_fop = &udf_file_operations;
1523 		inode->i_mode |= S_IFREG;
1524 		break;
1525 	case ICBTAG_FILE_TYPE_BLOCK:
1526 		inode->i_mode |= S_IFBLK;
1527 		break;
1528 	case ICBTAG_FILE_TYPE_CHAR:
1529 		inode->i_mode |= S_IFCHR;
1530 		break;
1531 	case ICBTAG_FILE_TYPE_FIFO:
1532 		init_special_inode(inode, inode->i_mode | S_IFIFO, 0);
1533 		break;
1534 	case ICBTAG_FILE_TYPE_SOCKET:
1535 		init_special_inode(inode, inode->i_mode | S_IFSOCK, 0);
1536 		break;
1537 	case ICBTAG_FILE_TYPE_SYMLINK:
1538 		inode->i_data.a_ops = &udf_symlink_aops;
1539 		inode->i_op = &udf_symlink_inode_operations;
1540 		inode_nohighmem(inode);
1541 		inode->i_mode = S_IFLNK | 0777;
1542 		break;
1543 	case ICBTAG_FILE_TYPE_MAIN:
1544 		udf_debug("METADATA FILE-----\n");
1545 		break;
1546 	case ICBTAG_FILE_TYPE_MIRROR:
1547 		udf_debug("METADATA MIRROR FILE-----\n");
1548 		break;
1549 	case ICBTAG_FILE_TYPE_BITMAP:
1550 		udf_debug("METADATA BITMAP FILE-----\n");
1551 		break;
1552 	default:
1553 		udf_err(inode->i_sb, "(ino %lu) failed unknown file type=%u\n",
1554 			inode->i_ino, fe->icbTag.fileType);
1555 		goto out;
1556 	}
1557 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1558 		struct deviceSpec *dsea =
1559 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1560 		if (dsea) {
1561 			init_special_inode(inode, inode->i_mode,
1562 				MKDEV(le32_to_cpu(dsea->majorDeviceIdent),
1563 				      le32_to_cpu(dsea->minorDeviceIdent)));
1564 			/* Developer ID ??? */
1565 		} else
1566 			goto out;
1567 	}
1568 	ret = 0;
1569 out:
1570 	brelse(bh);
1571 	return ret;
1572 }
1573 
1574 static int udf_alloc_i_data(struct inode *inode, size_t size)
1575 {
1576 	struct udf_inode_info *iinfo = UDF_I(inode);
1577 	iinfo->i_ext.i_data = kmalloc(size, GFP_KERNEL);
1578 	if (!iinfo->i_ext.i_data)
1579 		return -ENOMEM;
1580 	return 0;
1581 }
1582 
1583 static umode_t udf_convert_permissions(struct fileEntry *fe)
1584 {
1585 	umode_t mode;
1586 	uint32_t permissions;
1587 	uint32_t flags;
1588 
1589 	permissions = le32_to_cpu(fe->permissions);
1590 	flags = le16_to_cpu(fe->icbTag.flags);
1591 
1592 	mode =	((permissions) & 0007) |
1593 		((permissions >> 2) & 0070) |
1594 		((permissions >> 4) & 0700) |
1595 		((flags & ICBTAG_FLAG_SETUID) ? S_ISUID : 0) |
1596 		((flags & ICBTAG_FLAG_SETGID) ? S_ISGID : 0) |
1597 		((flags & ICBTAG_FLAG_STICKY) ? S_ISVTX : 0);
1598 
1599 	return mode;
1600 }
1601 
1602 int udf_write_inode(struct inode *inode, struct writeback_control *wbc)
1603 {
1604 	return udf_update_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
1605 }
1606 
1607 static int udf_sync_inode(struct inode *inode)
1608 {
1609 	return udf_update_inode(inode, 1);
1610 }
1611 
1612 static void udf_adjust_time(struct udf_inode_info *iinfo, struct timespec time)
1613 {
1614 	if (iinfo->i_crtime.tv_sec > time.tv_sec ||
1615 	    (iinfo->i_crtime.tv_sec == time.tv_sec &&
1616 	     iinfo->i_crtime.tv_nsec > time.tv_nsec))
1617 		iinfo->i_crtime = time;
1618 }
1619 
1620 static int udf_update_inode(struct inode *inode, int do_sync)
1621 {
1622 	struct buffer_head *bh = NULL;
1623 	struct fileEntry *fe;
1624 	struct extendedFileEntry *efe;
1625 	uint64_t lb_recorded;
1626 	uint32_t udfperms;
1627 	uint16_t icbflags;
1628 	uint16_t crclen;
1629 	int err = 0;
1630 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1631 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1632 	struct udf_inode_info *iinfo = UDF_I(inode);
1633 
1634 	bh = udf_tgetblk(inode->i_sb,
1635 			udf_get_lb_pblock(inode->i_sb, &iinfo->i_location, 0));
1636 	if (!bh) {
1637 		udf_debug("getblk failure\n");
1638 		return -EIO;
1639 	}
1640 
1641 	lock_buffer(bh);
1642 	memset(bh->b_data, 0, inode->i_sb->s_blocksize);
1643 	fe = (struct fileEntry *)bh->b_data;
1644 	efe = (struct extendedFileEntry *)bh->b_data;
1645 
1646 	if (iinfo->i_use) {
1647 		struct unallocSpaceEntry *use =
1648 			(struct unallocSpaceEntry *)bh->b_data;
1649 
1650 		use->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1651 		memcpy(bh->b_data + sizeof(struct unallocSpaceEntry),
1652 		       iinfo->i_ext.i_data, inode->i_sb->s_blocksize -
1653 					sizeof(struct unallocSpaceEntry));
1654 		use->descTag.tagIdent = cpu_to_le16(TAG_IDENT_USE);
1655 		crclen = sizeof(struct unallocSpaceEntry);
1656 
1657 		goto finish;
1658 	}
1659 
1660 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_FORGET))
1661 		fe->uid = cpu_to_le32(UDF_INVALID_ID);
1662 	else
1663 		fe->uid = cpu_to_le32(i_uid_read(inode));
1664 
1665 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_FORGET))
1666 		fe->gid = cpu_to_le32(UDF_INVALID_ID);
1667 	else
1668 		fe->gid = cpu_to_le32(i_gid_read(inode));
1669 
1670 	udfperms = ((inode->i_mode & 0007)) |
1671 		   ((inode->i_mode & 0070) << 2) |
1672 		   ((inode->i_mode & 0700) << 4);
1673 
1674 	udfperms |= (le32_to_cpu(fe->permissions) &
1675 		    (FE_PERM_O_DELETE | FE_PERM_O_CHATTR |
1676 		     FE_PERM_G_DELETE | FE_PERM_G_CHATTR |
1677 		     FE_PERM_U_DELETE | FE_PERM_U_CHATTR));
1678 	fe->permissions = cpu_to_le32(udfperms);
1679 
1680 	if (S_ISDIR(inode->i_mode) && inode->i_nlink > 0)
1681 		fe->fileLinkCount = cpu_to_le16(inode->i_nlink - 1);
1682 	else
1683 		fe->fileLinkCount = cpu_to_le16(inode->i_nlink);
1684 
1685 	fe->informationLength = cpu_to_le64(inode->i_size);
1686 
1687 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1688 		struct regid *eid;
1689 		struct deviceSpec *dsea =
1690 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1691 		if (!dsea) {
1692 			dsea = (struct deviceSpec *)
1693 				udf_add_extendedattr(inode,
1694 						     sizeof(struct deviceSpec) +
1695 						     sizeof(struct regid), 12, 0x3);
1696 			dsea->attrType = cpu_to_le32(12);
1697 			dsea->attrSubtype = 1;
1698 			dsea->attrLength = cpu_to_le32(
1699 						sizeof(struct deviceSpec) +
1700 						sizeof(struct regid));
1701 			dsea->impUseLength = cpu_to_le32(sizeof(struct regid));
1702 		}
1703 		eid = (struct regid *)dsea->impUse;
1704 		memset(eid, 0, sizeof(*eid));
1705 		strcpy(eid->ident, UDF_ID_DEVELOPER);
1706 		eid->identSuffix[0] = UDF_OS_CLASS_UNIX;
1707 		eid->identSuffix[1] = UDF_OS_ID_LINUX;
1708 		dsea->majorDeviceIdent = cpu_to_le32(imajor(inode));
1709 		dsea->minorDeviceIdent = cpu_to_le32(iminor(inode));
1710 	}
1711 
1712 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1713 		lb_recorded = 0; /* No extents => no blocks! */
1714 	else
1715 		lb_recorded =
1716 			(inode->i_blocks + (1 << (blocksize_bits - 9)) - 1) >>
1717 			(blocksize_bits - 9);
1718 
1719 	if (iinfo->i_efe == 0) {
1720 		memcpy(bh->b_data + sizeof(struct fileEntry),
1721 		       iinfo->i_ext.i_data,
1722 		       inode->i_sb->s_blocksize - sizeof(struct fileEntry));
1723 		fe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
1724 
1725 		udf_time_to_disk_stamp(&fe->accessTime, inode->i_atime);
1726 		udf_time_to_disk_stamp(&fe->modificationTime, inode->i_mtime);
1727 		udf_time_to_disk_stamp(&fe->attrTime, inode->i_ctime);
1728 		memset(&(fe->impIdent), 0, sizeof(struct regid));
1729 		strcpy(fe->impIdent.ident, UDF_ID_DEVELOPER);
1730 		fe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1731 		fe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1732 		fe->uniqueID = cpu_to_le64(iinfo->i_unique);
1733 		fe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
1734 		fe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1735 		fe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
1736 		fe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_FE);
1737 		crclen = sizeof(struct fileEntry);
1738 	} else {
1739 		memcpy(bh->b_data + sizeof(struct extendedFileEntry),
1740 		       iinfo->i_ext.i_data,
1741 		       inode->i_sb->s_blocksize -
1742 					sizeof(struct extendedFileEntry));
1743 		efe->objectSize = cpu_to_le64(inode->i_size);
1744 		efe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
1745 
1746 		udf_adjust_time(iinfo, inode->i_atime);
1747 		udf_adjust_time(iinfo, inode->i_mtime);
1748 		udf_adjust_time(iinfo, inode->i_ctime);
1749 
1750 		udf_time_to_disk_stamp(&efe->accessTime, inode->i_atime);
1751 		udf_time_to_disk_stamp(&efe->modificationTime, inode->i_mtime);
1752 		udf_time_to_disk_stamp(&efe->createTime, iinfo->i_crtime);
1753 		udf_time_to_disk_stamp(&efe->attrTime, inode->i_ctime);
1754 
1755 		memset(&(efe->impIdent), 0, sizeof(efe->impIdent));
1756 		strcpy(efe->impIdent.ident, UDF_ID_DEVELOPER);
1757 		efe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1758 		efe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1759 		efe->uniqueID = cpu_to_le64(iinfo->i_unique);
1760 		efe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
1761 		efe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1762 		efe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
1763 		efe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EFE);
1764 		crclen = sizeof(struct extendedFileEntry);
1765 	}
1766 
1767 finish:
1768 	if (iinfo->i_strat4096) {
1769 		fe->icbTag.strategyType = cpu_to_le16(4096);
1770 		fe->icbTag.strategyParameter = cpu_to_le16(1);
1771 		fe->icbTag.numEntries = cpu_to_le16(2);
1772 	} else {
1773 		fe->icbTag.strategyType = cpu_to_le16(4);
1774 		fe->icbTag.numEntries = cpu_to_le16(1);
1775 	}
1776 
1777 	if (iinfo->i_use)
1778 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_USE;
1779 	else if (S_ISDIR(inode->i_mode))
1780 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_DIRECTORY;
1781 	else if (S_ISREG(inode->i_mode))
1782 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_REGULAR;
1783 	else if (S_ISLNK(inode->i_mode))
1784 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SYMLINK;
1785 	else if (S_ISBLK(inode->i_mode))
1786 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_BLOCK;
1787 	else if (S_ISCHR(inode->i_mode))
1788 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_CHAR;
1789 	else if (S_ISFIFO(inode->i_mode))
1790 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_FIFO;
1791 	else if (S_ISSOCK(inode->i_mode))
1792 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SOCKET;
1793 
1794 	icbflags =	iinfo->i_alloc_type |
1795 			((inode->i_mode & S_ISUID) ? ICBTAG_FLAG_SETUID : 0) |
1796 			((inode->i_mode & S_ISGID) ? ICBTAG_FLAG_SETGID : 0) |
1797 			((inode->i_mode & S_ISVTX) ? ICBTAG_FLAG_STICKY : 0) |
1798 			(le16_to_cpu(fe->icbTag.flags) &
1799 				~(ICBTAG_FLAG_AD_MASK | ICBTAG_FLAG_SETUID |
1800 				ICBTAG_FLAG_SETGID | ICBTAG_FLAG_STICKY));
1801 
1802 	fe->icbTag.flags = cpu_to_le16(icbflags);
1803 	if (sbi->s_udfrev >= 0x0200)
1804 		fe->descTag.descVersion = cpu_to_le16(3);
1805 	else
1806 		fe->descTag.descVersion = cpu_to_le16(2);
1807 	fe->descTag.tagSerialNum = cpu_to_le16(sbi->s_serial_number);
1808 	fe->descTag.tagLocation = cpu_to_le32(
1809 					iinfo->i_location.logicalBlockNum);
1810 	crclen += iinfo->i_lenEAttr + iinfo->i_lenAlloc - sizeof(struct tag);
1811 	fe->descTag.descCRCLength = cpu_to_le16(crclen);
1812 	fe->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)fe + sizeof(struct tag),
1813 						  crclen));
1814 	fe->descTag.tagChecksum = udf_tag_checksum(&fe->descTag);
1815 
1816 	set_buffer_uptodate(bh);
1817 	unlock_buffer(bh);
1818 
1819 	/* write the data blocks */
1820 	mark_buffer_dirty(bh);
1821 	if (do_sync) {
1822 		sync_dirty_buffer(bh);
1823 		if (buffer_write_io_error(bh)) {
1824 			udf_warn(inode->i_sb, "IO error syncing udf inode [%08lx]\n",
1825 				 inode->i_ino);
1826 			err = -EIO;
1827 		}
1828 	}
1829 	brelse(bh);
1830 
1831 	return err;
1832 }
1833 
1834 struct inode *__udf_iget(struct super_block *sb, struct kernel_lb_addr *ino,
1835 			 bool hidden_inode)
1836 {
1837 	unsigned long block = udf_get_lb_pblock(sb, ino, 0);
1838 	struct inode *inode = iget_locked(sb, block);
1839 	int err;
1840 
1841 	if (!inode)
1842 		return ERR_PTR(-ENOMEM);
1843 
1844 	if (!(inode->i_state & I_NEW))
1845 		return inode;
1846 
1847 	memcpy(&UDF_I(inode)->i_location, ino, sizeof(struct kernel_lb_addr));
1848 	err = udf_read_inode(inode, hidden_inode);
1849 	if (err < 0) {
1850 		iget_failed(inode);
1851 		return ERR_PTR(err);
1852 	}
1853 	unlock_new_inode(inode);
1854 
1855 	return inode;
1856 }
1857 
1858 int udf_setup_indirect_aext(struct inode *inode, udf_pblk_t block,
1859 			    struct extent_position *epos)
1860 {
1861 	struct super_block *sb = inode->i_sb;
1862 	struct buffer_head *bh;
1863 	struct allocExtDesc *aed;
1864 	struct extent_position nepos;
1865 	struct kernel_lb_addr neloc;
1866 	int ver, adsize;
1867 
1868 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
1869 		adsize = sizeof(struct short_ad);
1870 	else if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_LONG)
1871 		adsize = sizeof(struct long_ad);
1872 	else
1873 		return -EIO;
1874 
1875 	neloc.logicalBlockNum = block;
1876 	neloc.partitionReferenceNum = epos->block.partitionReferenceNum;
1877 
1878 	bh = udf_tgetblk(sb, udf_get_lb_pblock(sb, &neloc, 0));
1879 	if (!bh)
1880 		return -EIO;
1881 	lock_buffer(bh);
1882 	memset(bh->b_data, 0x00, sb->s_blocksize);
1883 	set_buffer_uptodate(bh);
1884 	unlock_buffer(bh);
1885 	mark_buffer_dirty_inode(bh, inode);
1886 
1887 	aed = (struct allocExtDesc *)(bh->b_data);
1888 	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT)) {
1889 		aed->previousAllocExtLocation =
1890 				cpu_to_le32(epos->block.logicalBlockNum);
1891 	}
1892 	aed->lengthAllocDescs = cpu_to_le32(0);
1893 	if (UDF_SB(sb)->s_udfrev >= 0x0200)
1894 		ver = 3;
1895 	else
1896 		ver = 2;
1897 	udf_new_tag(bh->b_data, TAG_IDENT_AED, ver, 1, block,
1898 		    sizeof(struct tag));
1899 
1900 	nepos.block = neloc;
1901 	nepos.offset = sizeof(struct allocExtDesc);
1902 	nepos.bh = bh;
1903 
1904 	/*
1905 	 * Do we have to copy current last extent to make space for indirect
1906 	 * one?
1907 	 */
1908 	if (epos->offset + adsize > sb->s_blocksize) {
1909 		struct kernel_lb_addr cp_loc;
1910 		uint32_t cp_len;
1911 		int cp_type;
1912 
1913 		epos->offset -= adsize;
1914 		cp_type = udf_current_aext(inode, epos, &cp_loc, &cp_len, 0);
1915 		cp_len |= ((uint32_t)cp_type) << 30;
1916 
1917 		__udf_add_aext(inode, &nepos, &cp_loc, cp_len, 1);
1918 		udf_write_aext(inode, epos, &nepos.block,
1919 			       sb->s_blocksize | EXT_NEXT_EXTENT_ALLOCDECS, 0);
1920 	} else {
1921 		__udf_add_aext(inode, epos, &nepos.block,
1922 			       sb->s_blocksize | EXT_NEXT_EXTENT_ALLOCDECS, 0);
1923 	}
1924 
1925 	brelse(epos->bh);
1926 	*epos = nepos;
1927 
1928 	return 0;
1929 }
1930 
1931 /*
1932  * Append extent at the given position - should be the first free one in inode
1933  * / indirect extent. This function assumes there is enough space in the inode
1934  * or indirect extent. Use udf_add_aext() if you didn't check for this before.
1935  */
1936 int __udf_add_aext(struct inode *inode, struct extent_position *epos,
1937 		   struct kernel_lb_addr *eloc, uint32_t elen, int inc)
1938 {
1939 	struct udf_inode_info *iinfo = UDF_I(inode);
1940 	struct allocExtDesc *aed;
1941 	int adsize;
1942 
1943 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
1944 		adsize = sizeof(struct short_ad);
1945 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
1946 		adsize = sizeof(struct long_ad);
1947 	else
1948 		return -EIO;
1949 
1950 	if (!epos->bh) {
1951 		WARN_ON(iinfo->i_lenAlloc !=
1952 			epos->offset - udf_file_entry_alloc_offset(inode));
1953 	} else {
1954 		aed = (struct allocExtDesc *)epos->bh->b_data;
1955 		WARN_ON(le32_to_cpu(aed->lengthAllocDescs) !=
1956 			epos->offset - sizeof(struct allocExtDesc));
1957 		WARN_ON(epos->offset + adsize > inode->i_sb->s_blocksize);
1958 	}
1959 
1960 	udf_write_aext(inode, epos, eloc, elen, inc);
1961 
1962 	if (!epos->bh) {
1963 		iinfo->i_lenAlloc += adsize;
1964 		mark_inode_dirty(inode);
1965 	} else {
1966 		aed = (struct allocExtDesc *)epos->bh->b_data;
1967 		le32_add_cpu(&aed->lengthAllocDescs, adsize);
1968 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
1969 				UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
1970 			udf_update_tag(epos->bh->b_data,
1971 					epos->offset + (inc ? 0 : adsize));
1972 		else
1973 			udf_update_tag(epos->bh->b_data,
1974 					sizeof(struct allocExtDesc));
1975 		mark_buffer_dirty_inode(epos->bh, inode);
1976 	}
1977 
1978 	return 0;
1979 }
1980 
1981 /*
1982  * Append extent at given position - should be the first free one in inode
1983  * / indirect extent. Takes care of allocating and linking indirect blocks.
1984  */
1985 int udf_add_aext(struct inode *inode, struct extent_position *epos,
1986 		 struct kernel_lb_addr *eloc, uint32_t elen, int inc)
1987 {
1988 	int adsize;
1989 	struct super_block *sb = inode->i_sb;
1990 
1991 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
1992 		adsize = sizeof(struct short_ad);
1993 	else if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_LONG)
1994 		adsize = sizeof(struct long_ad);
1995 	else
1996 		return -EIO;
1997 
1998 	if (epos->offset + (2 * adsize) > sb->s_blocksize) {
1999 		int err;
2000 		udf_pblk_t new_block;
2001 
2002 		new_block = udf_new_block(sb, NULL,
2003 					  epos->block.partitionReferenceNum,
2004 					  epos->block.logicalBlockNum, &err);
2005 		if (!new_block)
2006 			return -ENOSPC;
2007 
2008 		err = udf_setup_indirect_aext(inode, new_block, epos);
2009 		if (err)
2010 			return err;
2011 	}
2012 
2013 	return __udf_add_aext(inode, epos, eloc, elen, inc);
2014 }
2015 
2016 void udf_write_aext(struct inode *inode, struct extent_position *epos,
2017 		    struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2018 {
2019 	int adsize;
2020 	uint8_t *ptr;
2021 	struct short_ad *sad;
2022 	struct long_ad *lad;
2023 	struct udf_inode_info *iinfo = UDF_I(inode);
2024 
2025 	if (!epos->bh)
2026 		ptr = iinfo->i_ext.i_data + epos->offset -
2027 			udf_file_entry_alloc_offset(inode) +
2028 			iinfo->i_lenEAttr;
2029 	else
2030 		ptr = epos->bh->b_data + epos->offset;
2031 
2032 	switch (iinfo->i_alloc_type) {
2033 	case ICBTAG_FLAG_AD_SHORT:
2034 		sad = (struct short_ad *)ptr;
2035 		sad->extLength = cpu_to_le32(elen);
2036 		sad->extPosition = cpu_to_le32(eloc->logicalBlockNum);
2037 		adsize = sizeof(struct short_ad);
2038 		break;
2039 	case ICBTAG_FLAG_AD_LONG:
2040 		lad = (struct long_ad *)ptr;
2041 		lad->extLength = cpu_to_le32(elen);
2042 		lad->extLocation = cpu_to_lelb(*eloc);
2043 		memset(lad->impUse, 0x00, sizeof(lad->impUse));
2044 		adsize = sizeof(struct long_ad);
2045 		break;
2046 	default:
2047 		return;
2048 	}
2049 
2050 	if (epos->bh) {
2051 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2052 		    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201) {
2053 			struct allocExtDesc *aed =
2054 				(struct allocExtDesc *)epos->bh->b_data;
2055 			udf_update_tag(epos->bh->b_data,
2056 				       le32_to_cpu(aed->lengthAllocDescs) +
2057 				       sizeof(struct allocExtDesc));
2058 		}
2059 		mark_buffer_dirty_inode(epos->bh, inode);
2060 	} else {
2061 		mark_inode_dirty(inode);
2062 	}
2063 
2064 	if (inc)
2065 		epos->offset += adsize;
2066 }
2067 
2068 /*
2069  * Only 1 indirect extent in a row really makes sense but allow upto 16 in case
2070  * someone does some weird stuff.
2071  */
2072 #define UDF_MAX_INDIR_EXTS 16
2073 
2074 int8_t udf_next_aext(struct inode *inode, struct extent_position *epos,
2075 		     struct kernel_lb_addr *eloc, uint32_t *elen, int inc)
2076 {
2077 	int8_t etype;
2078 	unsigned int indirections = 0;
2079 
2080 	while ((etype = udf_current_aext(inode, epos, eloc, elen, inc)) ==
2081 	       (EXT_NEXT_EXTENT_ALLOCDECS >> 30)) {
2082 		udf_pblk_t block;
2083 
2084 		if (++indirections > UDF_MAX_INDIR_EXTS) {
2085 			udf_err(inode->i_sb,
2086 				"too many indirect extents in inode %lu\n",
2087 				inode->i_ino);
2088 			return -1;
2089 		}
2090 
2091 		epos->block = *eloc;
2092 		epos->offset = sizeof(struct allocExtDesc);
2093 		brelse(epos->bh);
2094 		block = udf_get_lb_pblock(inode->i_sb, &epos->block, 0);
2095 		epos->bh = udf_tread(inode->i_sb, block);
2096 		if (!epos->bh) {
2097 			udf_debug("reading block %u failed!\n", block);
2098 			return -1;
2099 		}
2100 	}
2101 
2102 	return etype;
2103 }
2104 
2105 int8_t udf_current_aext(struct inode *inode, struct extent_position *epos,
2106 			struct kernel_lb_addr *eloc, uint32_t *elen, int inc)
2107 {
2108 	int alen;
2109 	int8_t etype;
2110 	uint8_t *ptr;
2111 	struct short_ad *sad;
2112 	struct long_ad *lad;
2113 	struct udf_inode_info *iinfo = UDF_I(inode);
2114 
2115 	if (!epos->bh) {
2116 		if (!epos->offset)
2117 			epos->offset = udf_file_entry_alloc_offset(inode);
2118 		ptr = iinfo->i_ext.i_data + epos->offset -
2119 			udf_file_entry_alloc_offset(inode) +
2120 			iinfo->i_lenEAttr;
2121 		alen = udf_file_entry_alloc_offset(inode) +
2122 							iinfo->i_lenAlloc;
2123 	} else {
2124 		if (!epos->offset)
2125 			epos->offset = sizeof(struct allocExtDesc);
2126 		ptr = epos->bh->b_data + epos->offset;
2127 		alen = sizeof(struct allocExtDesc) +
2128 			le32_to_cpu(((struct allocExtDesc *)epos->bh->b_data)->
2129 							lengthAllocDescs);
2130 	}
2131 
2132 	switch (iinfo->i_alloc_type) {
2133 	case ICBTAG_FLAG_AD_SHORT:
2134 		sad = udf_get_fileshortad(ptr, alen, &epos->offset, inc);
2135 		if (!sad)
2136 			return -1;
2137 		etype = le32_to_cpu(sad->extLength) >> 30;
2138 		eloc->logicalBlockNum = le32_to_cpu(sad->extPosition);
2139 		eloc->partitionReferenceNum =
2140 				iinfo->i_location.partitionReferenceNum;
2141 		*elen = le32_to_cpu(sad->extLength) & UDF_EXTENT_LENGTH_MASK;
2142 		break;
2143 	case ICBTAG_FLAG_AD_LONG:
2144 		lad = udf_get_filelongad(ptr, alen, &epos->offset, inc);
2145 		if (!lad)
2146 			return -1;
2147 		etype = le32_to_cpu(lad->extLength) >> 30;
2148 		*eloc = lelb_to_cpu(lad->extLocation);
2149 		*elen = le32_to_cpu(lad->extLength) & UDF_EXTENT_LENGTH_MASK;
2150 		break;
2151 	default:
2152 		udf_debug("alloc_type = %u unsupported\n", iinfo->i_alloc_type);
2153 		return -1;
2154 	}
2155 
2156 	return etype;
2157 }
2158 
2159 static int8_t udf_insert_aext(struct inode *inode, struct extent_position epos,
2160 			      struct kernel_lb_addr neloc, uint32_t nelen)
2161 {
2162 	struct kernel_lb_addr oeloc;
2163 	uint32_t oelen;
2164 	int8_t etype;
2165 
2166 	if (epos.bh)
2167 		get_bh(epos.bh);
2168 
2169 	while ((etype = udf_next_aext(inode, &epos, &oeloc, &oelen, 0)) != -1) {
2170 		udf_write_aext(inode, &epos, &neloc, nelen, 1);
2171 		neloc = oeloc;
2172 		nelen = (etype << 30) | oelen;
2173 	}
2174 	udf_add_aext(inode, &epos, &neloc, nelen, 1);
2175 	brelse(epos.bh);
2176 
2177 	return (nelen >> 30);
2178 }
2179 
2180 int8_t udf_delete_aext(struct inode *inode, struct extent_position epos,
2181 		       struct kernel_lb_addr eloc, uint32_t elen)
2182 {
2183 	struct extent_position oepos;
2184 	int adsize;
2185 	int8_t etype;
2186 	struct allocExtDesc *aed;
2187 	struct udf_inode_info *iinfo;
2188 
2189 	if (epos.bh) {
2190 		get_bh(epos.bh);
2191 		get_bh(epos.bh);
2192 	}
2193 
2194 	iinfo = UDF_I(inode);
2195 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2196 		adsize = sizeof(struct short_ad);
2197 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2198 		adsize = sizeof(struct long_ad);
2199 	else
2200 		adsize = 0;
2201 
2202 	oepos = epos;
2203 	if (udf_next_aext(inode, &epos, &eloc, &elen, 1) == -1)
2204 		return -1;
2205 
2206 	while ((etype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1) {
2207 		udf_write_aext(inode, &oepos, &eloc, (etype << 30) | elen, 1);
2208 		if (oepos.bh != epos.bh) {
2209 			oepos.block = epos.block;
2210 			brelse(oepos.bh);
2211 			get_bh(epos.bh);
2212 			oepos.bh = epos.bh;
2213 			oepos.offset = epos.offset - adsize;
2214 		}
2215 	}
2216 	memset(&eloc, 0x00, sizeof(struct kernel_lb_addr));
2217 	elen = 0;
2218 
2219 	if (epos.bh != oepos.bh) {
2220 		udf_free_blocks(inode->i_sb, inode, &epos.block, 0, 1);
2221 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2222 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2223 		if (!oepos.bh) {
2224 			iinfo->i_lenAlloc -= (adsize * 2);
2225 			mark_inode_dirty(inode);
2226 		} else {
2227 			aed = (struct allocExtDesc *)oepos.bh->b_data;
2228 			le32_add_cpu(&aed->lengthAllocDescs, -(2 * adsize));
2229 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2230 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2231 				udf_update_tag(oepos.bh->b_data,
2232 						oepos.offset - (2 * adsize));
2233 			else
2234 				udf_update_tag(oepos.bh->b_data,
2235 						sizeof(struct allocExtDesc));
2236 			mark_buffer_dirty_inode(oepos.bh, inode);
2237 		}
2238 	} else {
2239 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2240 		if (!oepos.bh) {
2241 			iinfo->i_lenAlloc -= adsize;
2242 			mark_inode_dirty(inode);
2243 		} else {
2244 			aed = (struct allocExtDesc *)oepos.bh->b_data;
2245 			le32_add_cpu(&aed->lengthAllocDescs, -adsize);
2246 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2247 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2248 				udf_update_tag(oepos.bh->b_data,
2249 						epos.offset - adsize);
2250 			else
2251 				udf_update_tag(oepos.bh->b_data,
2252 						sizeof(struct allocExtDesc));
2253 			mark_buffer_dirty_inode(oepos.bh, inode);
2254 		}
2255 	}
2256 
2257 	brelse(epos.bh);
2258 	brelse(oepos.bh);
2259 
2260 	return (elen >> 30);
2261 }
2262 
2263 int8_t inode_bmap(struct inode *inode, sector_t block,
2264 		  struct extent_position *pos, struct kernel_lb_addr *eloc,
2265 		  uint32_t *elen, sector_t *offset)
2266 {
2267 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
2268 	loff_t lbcount = 0, bcount = (loff_t) block << blocksize_bits;
2269 	int8_t etype;
2270 	struct udf_inode_info *iinfo;
2271 
2272 	iinfo = UDF_I(inode);
2273 	if (!udf_read_extent_cache(inode, bcount, &lbcount, pos)) {
2274 		pos->offset = 0;
2275 		pos->block = iinfo->i_location;
2276 		pos->bh = NULL;
2277 	}
2278 	*elen = 0;
2279 	do {
2280 		etype = udf_next_aext(inode, pos, eloc, elen, 1);
2281 		if (etype == -1) {
2282 			*offset = (bcount - lbcount) >> blocksize_bits;
2283 			iinfo->i_lenExtents = lbcount;
2284 			return -1;
2285 		}
2286 		lbcount += *elen;
2287 	} while (lbcount <= bcount);
2288 	/* update extent cache */
2289 	udf_update_extent_cache(inode, lbcount - *elen, pos);
2290 	*offset = (bcount + *elen - lbcount) >> blocksize_bits;
2291 
2292 	return etype;
2293 }
2294 
2295 udf_pblk_t udf_block_map(struct inode *inode, sector_t block)
2296 {
2297 	struct kernel_lb_addr eloc;
2298 	uint32_t elen;
2299 	sector_t offset;
2300 	struct extent_position epos = {};
2301 	udf_pblk_t ret;
2302 
2303 	down_read(&UDF_I(inode)->i_data_sem);
2304 
2305 	if (inode_bmap(inode, block, &epos, &eloc, &elen, &offset) ==
2306 						(EXT_RECORDED_ALLOCATED >> 30))
2307 		ret = udf_get_lb_pblock(inode->i_sb, &eloc, offset);
2308 	else
2309 		ret = 0;
2310 
2311 	up_read(&UDF_I(inode)->i_data_sem);
2312 	brelse(epos.bh);
2313 
2314 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_VARCONV))
2315 		return udf_fixed_to_variable(ret);
2316 	else
2317 		return ret;
2318 }
2319