xref: /openbmc/linux/fs/udf/inode.c (revision 4bce6fce)
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 
42 #include "udf_i.h"
43 #include "udf_sb.h"
44 
45 MODULE_AUTHOR("Ben Fennema");
46 MODULE_DESCRIPTION("Universal Disk Format Filesystem");
47 MODULE_LICENSE("GPL");
48 
49 #define EXTENT_MERGE_SIZE 5
50 
51 static umode_t udf_convert_permissions(struct fileEntry *);
52 static int udf_update_inode(struct inode *, int);
53 static int udf_sync_inode(struct inode *inode);
54 static int udf_alloc_i_data(struct inode *inode, size_t size);
55 static sector_t inode_getblk(struct inode *, sector_t, int *, int *);
56 static int8_t udf_insert_aext(struct inode *, struct extent_position,
57 			      struct kernel_lb_addr, uint32_t);
58 static void udf_split_extents(struct inode *, int *, int, int,
59 			      struct kernel_long_ad[EXTENT_MERGE_SIZE], int *);
60 static void udf_prealloc_extents(struct inode *, int, int,
61 				 struct kernel_long_ad[EXTENT_MERGE_SIZE], int *);
62 static void udf_merge_extents(struct inode *,
63 			      struct kernel_long_ad[EXTENT_MERGE_SIZE], int *);
64 static void udf_update_extents(struct inode *,
65 			       struct kernel_long_ad[EXTENT_MERGE_SIZE], int, int,
66 			       struct extent_position *);
67 static int udf_get_block(struct inode *, sector_t, struct buffer_head *, int);
68 
69 static void __udf_clear_extent_cache(struct inode *inode)
70 {
71 	struct udf_inode_info *iinfo = UDF_I(inode);
72 
73 	if (iinfo->cached_extent.lstart != -1) {
74 		brelse(iinfo->cached_extent.epos.bh);
75 		iinfo->cached_extent.lstart = -1;
76 	}
77 }
78 
79 /* Invalidate extent cache */
80 static void udf_clear_extent_cache(struct inode *inode)
81 {
82 	struct udf_inode_info *iinfo = UDF_I(inode);
83 
84 	spin_lock(&iinfo->i_extent_cache_lock);
85 	__udf_clear_extent_cache(inode);
86 	spin_unlock(&iinfo->i_extent_cache_lock);
87 }
88 
89 /* Return contents of extent cache */
90 static int udf_read_extent_cache(struct inode *inode, loff_t bcount,
91 				 loff_t *lbcount, struct extent_position *pos)
92 {
93 	struct udf_inode_info *iinfo = UDF_I(inode);
94 	int ret = 0;
95 
96 	spin_lock(&iinfo->i_extent_cache_lock);
97 	if ((iinfo->cached_extent.lstart <= bcount) &&
98 	    (iinfo->cached_extent.lstart != -1)) {
99 		/* Cache hit */
100 		*lbcount = iinfo->cached_extent.lstart;
101 		memcpy(pos, &iinfo->cached_extent.epos,
102 		       sizeof(struct extent_position));
103 		if (pos->bh)
104 			get_bh(pos->bh);
105 		ret = 1;
106 	}
107 	spin_unlock(&iinfo->i_extent_cache_lock);
108 	return ret;
109 }
110 
111 /* Add extent to extent cache */
112 static void udf_update_extent_cache(struct inode *inode, loff_t estart,
113 				    struct extent_position *pos, int next_epos)
114 {
115 	struct udf_inode_info *iinfo = UDF_I(inode);
116 
117 	spin_lock(&iinfo->i_extent_cache_lock);
118 	/* Invalidate previously cached extent */
119 	__udf_clear_extent_cache(inode);
120 	if (pos->bh)
121 		get_bh(pos->bh);
122 	memcpy(&iinfo->cached_extent.epos, pos,
123 	       sizeof(struct extent_position));
124 	iinfo->cached_extent.lstart = estart;
125 	if (next_epos)
126 		switch (iinfo->i_alloc_type) {
127 		case ICBTAG_FLAG_AD_SHORT:
128 			iinfo->cached_extent.epos.offset -=
129 			sizeof(struct short_ad);
130 			break;
131 		case ICBTAG_FLAG_AD_LONG:
132 			iinfo->cached_extent.epos.offset -=
133 			sizeof(struct long_ad);
134 		}
135 	spin_unlock(&iinfo->i_extent_cache_lock);
136 }
137 
138 void udf_evict_inode(struct inode *inode)
139 {
140 	struct udf_inode_info *iinfo = UDF_I(inode);
141 	int want_delete = 0;
142 
143 	if (!inode->i_nlink && !is_bad_inode(inode)) {
144 		want_delete = 1;
145 		udf_setsize(inode, 0);
146 		udf_update_inode(inode, IS_SYNC(inode));
147 	}
148 	truncate_inode_pages_final(&inode->i_data);
149 	invalidate_inode_buffers(inode);
150 	clear_inode(inode);
151 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB &&
152 	    inode->i_size != iinfo->i_lenExtents) {
153 		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",
154 			 inode->i_ino, inode->i_mode,
155 			 (unsigned long long)inode->i_size,
156 			 (unsigned long long)iinfo->i_lenExtents);
157 	}
158 	kfree(iinfo->i_ext.i_data);
159 	iinfo->i_ext.i_data = NULL;
160 	udf_clear_extent_cache(inode);
161 	if (want_delete) {
162 		udf_free_inode(inode);
163 	}
164 }
165 
166 static void udf_write_failed(struct address_space *mapping, loff_t to)
167 {
168 	struct inode *inode = mapping->host;
169 	struct udf_inode_info *iinfo = UDF_I(inode);
170 	loff_t isize = inode->i_size;
171 
172 	if (to > isize) {
173 		truncate_pagecache(inode, isize);
174 		if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
175 			down_write(&iinfo->i_data_sem);
176 			udf_clear_extent_cache(inode);
177 			udf_truncate_extents(inode);
178 			up_write(&iinfo->i_data_sem);
179 		}
180 	}
181 }
182 
183 static int udf_writepage(struct page *page, struct writeback_control *wbc)
184 {
185 	return block_write_full_page(page, udf_get_block, wbc);
186 }
187 
188 static int udf_writepages(struct address_space *mapping,
189 			struct writeback_control *wbc)
190 {
191 	return mpage_writepages(mapping, wbc, udf_get_block);
192 }
193 
194 static int udf_readpage(struct file *file, struct page *page)
195 {
196 	return mpage_readpage(page, udf_get_block);
197 }
198 
199 static int udf_readpages(struct file *file, struct address_space *mapping,
200 			struct list_head *pages, unsigned nr_pages)
201 {
202 	return mpage_readpages(mapping, pages, nr_pages, udf_get_block);
203 }
204 
205 static int udf_write_begin(struct file *file, struct address_space *mapping,
206 			loff_t pos, unsigned len, unsigned flags,
207 			struct page **pagep, void **fsdata)
208 {
209 	int ret;
210 
211 	ret = block_write_begin(mapping, pos, len, flags, pagep, udf_get_block);
212 	if (unlikely(ret))
213 		udf_write_failed(mapping, pos + len);
214 	return ret;
215 }
216 
217 static ssize_t udf_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
218 			     loff_t offset)
219 {
220 	struct file *file = iocb->ki_filp;
221 	struct address_space *mapping = file->f_mapping;
222 	struct inode *inode = mapping->host;
223 	size_t count = iov_iter_count(iter);
224 	ssize_t ret;
225 
226 	ret = blockdev_direct_IO(iocb, inode, iter, offset, udf_get_block);
227 	if (unlikely(ret < 0 && iov_iter_rw(iter) == WRITE))
228 		udf_write_failed(mapping, offset + count);
229 	return ret;
230 }
231 
232 static sector_t udf_bmap(struct address_space *mapping, sector_t block)
233 {
234 	return generic_block_bmap(mapping, block, udf_get_block);
235 }
236 
237 const struct address_space_operations udf_aops = {
238 	.readpage	= udf_readpage,
239 	.readpages	= udf_readpages,
240 	.writepage	= udf_writepage,
241 	.writepages	= udf_writepages,
242 	.write_begin	= udf_write_begin,
243 	.write_end	= generic_write_end,
244 	.direct_IO	= udf_direct_IO,
245 	.bmap		= udf_bmap,
246 };
247 
248 /*
249  * Expand file stored in ICB to a normal one-block-file
250  *
251  * This function requires i_data_sem for writing and releases it.
252  * This function requires i_mutex held
253  */
254 int udf_expand_file_adinicb(struct inode *inode)
255 {
256 	struct page *page;
257 	char *kaddr;
258 	struct udf_inode_info *iinfo = UDF_I(inode);
259 	int err;
260 	struct writeback_control udf_wbc = {
261 		.sync_mode = WB_SYNC_NONE,
262 		.nr_to_write = 1,
263 	};
264 
265 	WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
266 	if (!iinfo->i_lenAlloc) {
267 		if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
268 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
269 		else
270 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
271 		/* from now on we have normal address_space methods */
272 		inode->i_data.a_ops = &udf_aops;
273 		up_write(&iinfo->i_data_sem);
274 		mark_inode_dirty(inode);
275 		return 0;
276 	}
277 	/*
278 	 * Release i_data_sem so that we can lock a page - page lock ranks
279 	 * above i_data_sem. i_mutex still protects us against file changes.
280 	 */
281 	up_write(&iinfo->i_data_sem);
282 
283 	page = find_or_create_page(inode->i_mapping, 0, GFP_NOFS);
284 	if (!page)
285 		return -ENOMEM;
286 
287 	if (!PageUptodate(page)) {
288 		kaddr = kmap(page);
289 		memset(kaddr + iinfo->i_lenAlloc, 0x00,
290 		       PAGE_CACHE_SIZE - iinfo->i_lenAlloc);
291 		memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr,
292 			iinfo->i_lenAlloc);
293 		flush_dcache_page(page);
294 		SetPageUptodate(page);
295 		kunmap(page);
296 	}
297 	down_write(&iinfo->i_data_sem);
298 	memset(iinfo->i_ext.i_data + iinfo->i_lenEAttr, 0x00,
299 	       iinfo->i_lenAlloc);
300 	iinfo->i_lenAlloc = 0;
301 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
302 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
303 	else
304 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
305 	/* from now on we have normal address_space methods */
306 	inode->i_data.a_ops = &udf_aops;
307 	up_write(&iinfo->i_data_sem);
308 	err = inode->i_data.a_ops->writepage(page, &udf_wbc);
309 	if (err) {
310 		/* Restore everything back so that we don't lose data... */
311 		lock_page(page);
312 		kaddr = kmap(page);
313 		down_write(&iinfo->i_data_sem);
314 		memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr, kaddr,
315 		       inode->i_size);
316 		kunmap(page);
317 		unlock_page(page);
318 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
319 		inode->i_data.a_ops = &udf_adinicb_aops;
320 		up_write(&iinfo->i_data_sem);
321 	}
322 	page_cache_release(page);
323 	mark_inode_dirty(inode);
324 
325 	return err;
326 }
327 
328 struct buffer_head *udf_expand_dir_adinicb(struct inode *inode, int *block,
329 					   int *err)
330 {
331 	int newblock;
332 	struct buffer_head *dbh = NULL;
333 	struct kernel_lb_addr eloc;
334 	uint8_t alloctype;
335 	struct extent_position epos;
336 
337 	struct udf_fileident_bh sfibh, dfibh;
338 	loff_t f_pos = udf_ext0_offset(inode);
339 	int size = udf_ext0_offset(inode) + inode->i_size;
340 	struct fileIdentDesc cfi, *sfi, *dfi;
341 	struct udf_inode_info *iinfo = UDF_I(inode);
342 
343 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
344 		alloctype = ICBTAG_FLAG_AD_SHORT;
345 	else
346 		alloctype = ICBTAG_FLAG_AD_LONG;
347 
348 	if (!inode->i_size) {
349 		iinfo->i_alloc_type = alloctype;
350 		mark_inode_dirty(inode);
351 		return NULL;
352 	}
353 
354 	/* alloc block, and copy data to it */
355 	*block = udf_new_block(inode->i_sb, inode,
356 			       iinfo->i_location.partitionReferenceNum,
357 			       iinfo->i_location.logicalBlockNum, err);
358 	if (!(*block))
359 		return NULL;
360 	newblock = udf_get_pblock(inode->i_sb, *block,
361 				  iinfo->i_location.partitionReferenceNum,
362 				0);
363 	if (!newblock)
364 		return NULL;
365 	dbh = udf_tgetblk(inode->i_sb, newblock);
366 	if (!dbh)
367 		return NULL;
368 	lock_buffer(dbh);
369 	memset(dbh->b_data, 0x00, inode->i_sb->s_blocksize);
370 	set_buffer_uptodate(dbh);
371 	unlock_buffer(dbh);
372 	mark_buffer_dirty_inode(dbh, inode);
373 
374 	sfibh.soffset = sfibh.eoffset =
375 			f_pos & (inode->i_sb->s_blocksize - 1);
376 	sfibh.sbh = sfibh.ebh = NULL;
377 	dfibh.soffset = dfibh.eoffset = 0;
378 	dfibh.sbh = dfibh.ebh = dbh;
379 	while (f_pos < size) {
380 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
381 		sfi = udf_fileident_read(inode, &f_pos, &sfibh, &cfi, NULL,
382 					 NULL, NULL, NULL);
383 		if (!sfi) {
384 			brelse(dbh);
385 			return NULL;
386 		}
387 		iinfo->i_alloc_type = alloctype;
388 		sfi->descTag.tagLocation = cpu_to_le32(*block);
389 		dfibh.soffset = dfibh.eoffset;
390 		dfibh.eoffset += (sfibh.eoffset - sfibh.soffset);
391 		dfi = (struct fileIdentDesc *)(dbh->b_data + dfibh.soffset);
392 		if (udf_write_fi(inode, sfi, dfi, &dfibh, sfi->impUse,
393 				 sfi->fileIdent +
394 					le16_to_cpu(sfi->lengthOfImpUse))) {
395 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
396 			brelse(dbh);
397 			return NULL;
398 		}
399 	}
400 	mark_buffer_dirty_inode(dbh, inode);
401 
402 	memset(iinfo->i_ext.i_data + iinfo->i_lenEAttr, 0,
403 		iinfo->i_lenAlloc);
404 	iinfo->i_lenAlloc = 0;
405 	eloc.logicalBlockNum = *block;
406 	eloc.partitionReferenceNum =
407 				iinfo->i_location.partitionReferenceNum;
408 	iinfo->i_lenExtents = inode->i_size;
409 	epos.bh = NULL;
410 	epos.block = iinfo->i_location;
411 	epos.offset = udf_file_entry_alloc_offset(inode);
412 	udf_add_aext(inode, &epos, &eloc, inode->i_size, 0);
413 	/* UniqueID stuff */
414 
415 	brelse(epos.bh);
416 	mark_inode_dirty(inode);
417 	return dbh;
418 }
419 
420 static int udf_get_block(struct inode *inode, sector_t block,
421 			 struct buffer_head *bh_result, int create)
422 {
423 	int err, new;
424 	sector_t phys = 0;
425 	struct udf_inode_info *iinfo;
426 
427 	if (!create) {
428 		phys = udf_block_map(inode, block);
429 		if (phys)
430 			map_bh(bh_result, inode->i_sb, phys);
431 		return 0;
432 	}
433 
434 	err = -EIO;
435 	new = 0;
436 	iinfo = UDF_I(inode);
437 
438 	down_write(&iinfo->i_data_sem);
439 	if (block == iinfo->i_next_alloc_block + 1) {
440 		iinfo->i_next_alloc_block++;
441 		iinfo->i_next_alloc_goal++;
442 	}
443 
444 	udf_clear_extent_cache(inode);
445 	phys = inode_getblk(inode, block, &err, &new);
446 	if (!phys)
447 		goto abort;
448 
449 	if (new)
450 		set_buffer_new(bh_result);
451 	map_bh(bh_result, inode->i_sb, phys);
452 
453 abort:
454 	up_write(&iinfo->i_data_sem);
455 	return err;
456 }
457 
458 static struct buffer_head *udf_getblk(struct inode *inode, long block,
459 				      int create, int *err)
460 {
461 	struct buffer_head *bh;
462 	struct buffer_head dummy;
463 
464 	dummy.b_state = 0;
465 	dummy.b_blocknr = -1000;
466 	*err = udf_get_block(inode, block, &dummy, create);
467 	if (!*err && buffer_mapped(&dummy)) {
468 		bh = sb_getblk(inode->i_sb, dummy.b_blocknr);
469 		if (buffer_new(&dummy)) {
470 			lock_buffer(bh);
471 			memset(bh->b_data, 0x00, inode->i_sb->s_blocksize);
472 			set_buffer_uptodate(bh);
473 			unlock_buffer(bh);
474 			mark_buffer_dirty_inode(bh, inode);
475 		}
476 		return bh;
477 	}
478 
479 	return NULL;
480 }
481 
482 /* Extend the file by 'blocks' blocks, return the number of extents added */
483 static int udf_do_extend_file(struct inode *inode,
484 			      struct extent_position *last_pos,
485 			      struct kernel_long_ad *last_ext,
486 			      sector_t blocks)
487 {
488 	sector_t add;
489 	int count = 0, fake = !(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
490 	struct super_block *sb = inode->i_sb;
491 	struct kernel_lb_addr prealloc_loc = {};
492 	int prealloc_len = 0;
493 	struct udf_inode_info *iinfo;
494 	int err;
495 
496 	/* The previous extent is fake and we should not extend by anything
497 	 * - there's nothing to do... */
498 	if (!blocks && fake)
499 		return 0;
500 
501 	iinfo = UDF_I(inode);
502 	/* Round the last extent up to a multiple of block size */
503 	if (last_ext->extLength & (sb->s_blocksize - 1)) {
504 		last_ext->extLength =
505 			(last_ext->extLength & UDF_EXTENT_FLAG_MASK) |
506 			(((last_ext->extLength & UDF_EXTENT_LENGTH_MASK) +
507 			  sb->s_blocksize - 1) & ~(sb->s_blocksize - 1));
508 		iinfo->i_lenExtents =
509 			(iinfo->i_lenExtents + sb->s_blocksize - 1) &
510 			~(sb->s_blocksize - 1);
511 	}
512 
513 	/* Last extent are just preallocated blocks? */
514 	if ((last_ext->extLength & UDF_EXTENT_FLAG_MASK) ==
515 						EXT_NOT_RECORDED_ALLOCATED) {
516 		/* Save the extent so that we can reattach it to the end */
517 		prealloc_loc = last_ext->extLocation;
518 		prealloc_len = last_ext->extLength;
519 		/* Mark the extent as a hole */
520 		last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
521 			(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
522 		last_ext->extLocation.logicalBlockNum = 0;
523 		last_ext->extLocation.partitionReferenceNum = 0;
524 	}
525 
526 	/* Can we merge with the previous extent? */
527 	if ((last_ext->extLength & UDF_EXTENT_FLAG_MASK) ==
528 					EXT_NOT_RECORDED_NOT_ALLOCATED) {
529 		add = ((1 << 30) - sb->s_blocksize -
530 			(last_ext->extLength & UDF_EXTENT_LENGTH_MASK)) >>
531 			sb->s_blocksize_bits;
532 		if (add > blocks)
533 			add = blocks;
534 		blocks -= add;
535 		last_ext->extLength += add << sb->s_blocksize_bits;
536 	}
537 
538 	if (fake) {
539 		udf_add_aext(inode, last_pos, &last_ext->extLocation,
540 			     last_ext->extLength, 1);
541 		count++;
542 	} else
543 		udf_write_aext(inode, last_pos, &last_ext->extLocation,
544 				last_ext->extLength, 1);
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 	uint32_t newblocknum, newblock;
667 	sector_t offset = 0;
668 	int8_t etype;
669 	struct udf_inode_info *iinfo = UDF_I(inode);
670 	int 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 		brelse(prev_epos.bh);
742 		brelse(cur_epos.bh);
743 		brelse(next_epos.bh);
744 		newblock = udf_get_lb_pblock(inode->i_sb, &eloc, offset);
745 		return newblock;
746 	}
747 
748 	/* Are we beyond EOF? */
749 	if (etype == -1) {
750 		int ret;
751 		isBeyondEOF = true;
752 		if (count) {
753 			if (c)
754 				laarr[0] = laarr[1];
755 			startnum = 1;
756 		} else {
757 			/* Create a fake extent when there's not one */
758 			memset(&laarr[0].extLocation, 0x00,
759 				sizeof(struct kernel_lb_addr));
760 			laarr[0].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
761 			/* Will udf_do_extend_file() create real extent from
762 			   a fake one? */
763 			startnum = (offset > 0);
764 		}
765 		/* Create extents for the hole between EOF and offset */
766 		ret = udf_do_extend_file(inode, &prev_epos, laarr, offset);
767 		if (ret < 0) {
768 			brelse(prev_epos.bh);
769 			brelse(cur_epos.bh);
770 			brelse(next_epos.bh);
771 			*err = ret;
772 			return 0;
773 		}
774 		c = 0;
775 		offset = 0;
776 		count += ret;
777 		/* We are not covered by a preallocated extent? */
778 		if ((laarr[0].extLength & UDF_EXTENT_FLAG_MASK) !=
779 						EXT_NOT_RECORDED_ALLOCATED) {
780 			/* Is there any real extent? - otherwise we overwrite
781 			 * the fake one... */
782 			if (count)
783 				c = !c;
784 			laarr[c].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
785 				inode->i_sb->s_blocksize;
786 			memset(&laarr[c].extLocation, 0x00,
787 				sizeof(struct kernel_lb_addr));
788 			count++;
789 		}
790 		endnum = c + 1;
791 		lastblock = 1;
792 	} else {
793 		isBeyondEOF = false;
794 		endnum = startnum = ((count > 2) ? 2 : count);
795 
796 		/* if the current extent is in position 0,
797 		   swap it with the previous */
798 		if (!c && count != 1) {
799 			laarr[2] = laarr[0];
800 			laarr[0] = laarr[1];
801 			laarr[1] = laarr[2];
802 			c = 1;
803 		}
804 
805 		/* if the current block is located in an extent,
806 		   read the next extent */
807 		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 0);
808 		if (etype != -1) {
809 			laarr[c + 1].extLength = (etype << 30) | elen;
810 			laarr[c + 1].extLocation = eloc;
811 			count++;
812 			startnum++;
813 			endnum++;
814 		} else
815 			lastblock = 1;
816 	}
817 
818 	/* if the current extent is not recorded but allocated, get the
819 	 * block in the extent corresponding to the requested block */
820 	if ((laarr[c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30))
821 		newblocknum = laarr[c].extLocation.logicalBlockNum + offset;
822 	else { /* otherwise, allocate a new block */
823 		if (iinfo->i_next_alloc_block == block)
824 			goal = iinfo->i_next_alloc_goal;
825 
826 		if (!goal) {
827 			if (!(goal = pgoal)) /* XXX: what was intended here? */
828 				goal = iinfo->i_location.logicalBlockNum + 1;
829 		}
830 
831 		newblocknum = udf_new_block(inode->i_sb, inode,
832 				iinfo->i_location.partitionReferenceNum,
833 				goal, err);
834 		if (!newblocknum) {
835 			brelse(prev_epos.bh);
836 			brelse(cur_epos.bh);
837 			brelse(next_epos.bh);
838 			*err = -ENOSPC;
839 			return 0;
840 		}
841 		if (isBeyondEOF)
842 			iinfo->i_lenExtents += inode->i_sb->s_blocksize;
843 	}
844 
845 	/* if the extent the requsted block is located in contains multiple
846 	 * blocks, split the extent into at most three extents. blocks prior
847 	 * to requested block, requested block, and blocks after requested
848 	 * block */
849 	udf_split_extents(inode, &c, offset, newblocknum, laarr, &endnum);
850 
851 #ifdef UDF_PREALLOCATE
852 	/* We preallocate blocks only for regular files. It also makes sense
853 	 * for directories but there's a problem when to drop the
854 	 * preallocation. We might use some delayed work for that but I feel
855 	 * it's overengineering for a filesystem like UDF. */
856 	if (S_ISREG(inode->i_mode))
857 		udf_prealloc_extents(inode, c, lastblock, laarr, &endnum);
858 #endif
859 
860 	/* merge any continuous blocks in laarr */
861 	udf_merge_extents(inode, laarr, &endnum);
862 
863 	/* write back the new extents, inserting new extents if the new number
864 	 * of extents is greater than the old number, and deleting extents if
865 	 * the new number of extents is less than the old number */
866 	udf_update_extents(inode, laarr, startnum, endnum, &prev_epos);
867 
868 	brelse(prev_epos.bh);
869 	brelse(cur_epos.bh);
870 	brelse(next_epos.bh);
871 
872 	newblock = udf_get_pblock(inode->i_sb, newblocknum,
873 				iinfo->i_location.partitionReferenceNum, 0);
874 	if (!newblock) {
875 		*err = -EIO;
876 		return 0;
877 	}
878 	*new = 1;
879 	iinfo->i_next_alloc_block = block;
880 	iinfo->i_next_alloc_goal = newblocknum;
881 	inode->i_ctime = current_fs_time(inode->i_sb);
882 
883 	if (IS_SYNC(inode))
884 		udf_sync_inode(inode);
885 	else
886 		mark_inode_dirty(inode);
887 
888 	return newblock;
889 }
890 
891 static void udf_split_extents(struct inode *inode, int *c, int offset,
892 			      int newblocknum,
893 			      struct kernel_long_ad laarr[EXTENT_MERGE_SIZE],
894 			      int *endnum)
895 {
896 	unsigned long blocksize = inode->i_sb->s_blocksize;
897 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
898 
899 	if ((laarr[*c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30) ||
900 	    (laarr[*c].extLength >> 30) ==
901 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
902 		int curr = *c;
903 		int blen = ((laarr[curr].extLength & UDF_EXTENT_LENGTH_MASK) +
904 			    blocksize - 1) >> blocksize_bits;
905 		int8_t etype = (laarr[curr].extLength >> 30);
906 
907 		if (blen == 1)
908 			;
909 		else if (!offset || blen == offset + 1) {
910 			laarr[curr + 2] = laarr[curr + 1];
911 			laarr[curr + 1] = laarr[curr];
912 		} else {
913 			laarr[curr + 3] = laarr[curr + 1];
914 			laarr[curr + 2] = laarr[curr + 1] = laarr[curr];
915 		}
916 
917 		if (offset) {
918 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
919 				udf_free_blocks(inode->i_sb, inode,
920 						&laarr[curr].extLocation,
921 						0, offset);
922 				laarr[curr].extLength =
923 					EXT_NOT_RECORDED_NOT_ALLOCATED |
924 					(offset << blocksize_bits);
925 				laarr[curr].extLocation.logicalBlockNum = 0;
926 				laarr[curr].extLocation.
927 						partitionReferenceNum = 0;
928 			} else
929 				laarr[curr].extLength = (etype << 30) |
930 					(offset << blocksize_bits);
931 			curr++;
932 			(*c)++;
933 			(*endnum)++;
934 		}
935 
936 		laarr[curr].extLocation.logicalBlockNum = newblocknum;
937 		if (etype == (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
938 			laarr[curr].extLocation.partitionReferenceNum =
939 				UDF_I(inode)->i_location.partitionReferenceNum;
940 		laarr[curr].extLength = EXT_RECORDED_ALLOCATED |
941 			blocksize;
942 		curr++;
943 
944 		if (blen != offset + 1) {
945 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
946 				laarr[curr].extLocation.logicalBlockNum +=
947 								offset + 1;
948 			laarr[curr].extLength = (etype << 30) |
949 				((blen - (offset + 1)) << blocksize_bits);
950 			curr++;
951 			(*endnum)++;
952 		}
953 	}
954 }
955 
956 static void udf_prealloc_extents(struct inode *inode, int c, int lastblock,
957 				 struct kernel_long_ad laarr[EXTENT_MERGE_SIZE],
958 				 int *endnum)
959 {
960 	int start, length = 0, currlength = 0, i;
961 
962 	if (*endnum >= (c + 1)) {
963 		if (!lastblock)
964 			return;
965 		else
966 			start = c;
967 	} else {
968 		if ((laarr[c + 1].extLength >> 30) ==
969 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
970 			start = c + 1;
971 			length = currlength =
972 				(((laarr[c + 1].extLength &
973 					UDF_EXTENT_LENGTH_MASK) +
974 				inode->i_sb->s_blocksize - 1) >>
975 				inode->i_sb->s_blocksize_bits);
976 		} else
977 			start = c;
978 	}
979 
980 	for (i = start + 1; i <= *endnum; i++) {
981 		if (i == *endnum) {
982 			if (lastblock)
983 				length += UDF_DEFAULT_PREALLOC_BLOCKS;
984 		} else if ((laarr[i].extLength >> 30) ==
985 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
986 			length += (((laarr[i].extLength &
987 						UDF_EXTENT_LENGTH_MASK) +
988 				    inode->i_sb->s_blocksize - 1) >>
989 				    inode->i_sb->s_blocksize_bits);
990 		} else
991 			break;
992 	}
993 
994 	if (length) {
995 		int next = laarr[start].extLocation.logicalBlockNum +
996 			(((laarr[start].extLength & UDF_EXTENT_LENGTH_MASK) +
997 			  inode->i_sb->s_blocksize - 1) >>
998 			  inode->i_sb->s_blocksize_bits);
999 		int numalloc = udf_prealloc_blocks(inode->i_sb, inode,
1000 				laarr[start].extLocation.partitionReferenceNum,
1001 				next, (UDF_DEFAULT_PREALLOC_BLOCKS > length ?
1002 				length : UDF_DEFAULT_PREALLOC_BLOCKS) -
1003 				currlength);
1004 		if (numalloc) 	{
1005 			if (start == (c + 1))
1006 				laarr[start].extLength +=
1007 					(numalloc <<
1008 					 inode->i_sb->s_blocksize_bits);
1009 			else {
1010 				memmove(&laarr[c + 2], &laarr[c + 1],
1011 					sizeof(struct long_ad) * (*endnum - (c + 1)));
1012 				(*endnum)++;
1013 				laarr[c + 1].extLocation.logicalBlockNum = next;
1014 				laarr[c + 1].extLocation.partitionReferenceNum =
1015 					laarr[c].extLocation.
1016 							partitionReferenceNum;
1017 				laarr[c + 1].extLength =
1018 					EXT_NOT_RECORDED_ALLOCATED |
1019 					(numalloc <<
1020 					 inode->i_sb->s_blocksize_bits);
1021 				start = c + 1;
1022 			}
1023 
1024 			for (i = start + 1; numalloc && i < *endnum; i++) {
1025 				int elen = ((laarr[i].extLength &
1026 						UDF_EXTENT_LENGTH_MASK) +
1027 					    inode->i_sb->s_blocksize - 1) >>
1028 					    inode->i_sb->s_blocksize_bits;
1029 
1030 				if (elen > numalloc) {
1031 					laarr[i].extLength -=
1032 						(numalloc <<
1033 						 inode->i_sb->s_blocksize_bits);
1034 					numalloc = 0;
1035 				} else {
1036 					numalloc -= elen;
1037 					if (*endnum > (i + 1))
1038 						memmove(&laarr[i],
1039 							&laarr[i + 1],
1040 							sizeof(struct long_ad) *
1041 							(*endnum - (i + 1)));
1042 					i--;
1043 					(*endnum)--;
1044 				}
1045 			}
1046 			UDF_I(inode)->i_lenExtents +=
1047 				numalloc << inode->i_sb->s_blocksize_bits;
1048 		}
1049 	}
1050 }
1051 
1052 static void udf_merge_extents(struct inode *inode,
1053 			      struct kernel_long_ad laarr[EXTENT_MERGE_SIZE],
1054 			      int *endnum)
1055 {
1056 	int i;
1057 	unsigned long blocksize = inode->i_sb->s_blocksize;
1058 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1059 
1060 	for (i = 0; i < (*endnum - 1); i++) {
1061 		struct kernel_long_ad *li /*l[i]*/ = &laarr[i];
1062 		struct kernel_long_ad *lip1 /*l[i plus 1]*/ = &laarr[i + 1];
1063 
1064 		if (((li->extLength >> 30) == (lip1->extLength >> 30)) &&
1065 			(((li->extLength >> 30) ==
1066 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) ||
1067 			((lip1->extLocation.logicalBlockNum -
1068 			  li->extLocation.logicalBlockNum) ==
1069 			(((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1070 			blocksize - 1) >> blocksize_bits)))) {
1071 
1072 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1073 				(lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1074 				blocksize - 1) & ~UDF_EXTENT_LENGTH_MASK) {
1075 				lip1->extLength = (lip1->extLength -
1076 						  (li->extLength &
1077 						   UDF_EXTENT_LENGTH_MASK) +
1078 						   UDF_EXTENT_LENGTH_MASK) &
1079 							~(blocksize - 1);
1080 				li->extLength = (li->extLength &
1081 						 UDF_EXTENT_FLAG_MASK) +
1082 						(UDF_EXTENT_LENGTH_MASK + 1) -
1083 						blocksize;
1084 				lip1->extLocation.logicalBlockNum =
1085 					li->extLocation.logicalBlockNum +
1086 					((li->extLength &
1087 						UDF_EXTENT_LENGTH_MASK) >>
1088 						blocksize_bits);
1089 			} else {
1090 				li->extLength = lip1->extLength +
1091 					(((li->extLength &
1092 						UDF_EXTENT_LENGTH_MASK) +
1093 					 blocksize - 1) & ~(blocksize - 1));
1094 				if (*endnum > (i + 2))
1095 					memmove(&laarr[i + 1], &laarr[i + 2],
1096 						sizeof(struct long_ad) *
1097 						(*endnum - (i + 2)));
1098 				i--;
1099 				(*endnum)--;
1100 			}
1101 		} else if (((li->extLength >> 30) ==
1102 				(EXT_NOT_RECORDED_ALLOCATED >> 30)) &&
1103 			   ((lip1->extLength >> 30) ==
1104 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))) {
1105 			udf_free_blocks(inode->i_sb, inode, &li->extLocation, 0,
1106 					((li->extLength &
1107 					  UDF_EXTENT_LENGTH_MASK) +
1108 					 blocksize - 1) >> blocksize_bits);
1109 			li->extLocation.logicalBlockNum = 0;
1110 			li->extLocation.partitionReferenceNum = 0;
1111 
1112 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1113 			     (lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1114 			     blocksize - 1) & ~UDF_EXTENT_LENGTH_MASK) {
1115 				lip1->extLength = (lip1->extLength -
1116 						   (li->extLength &
1117 						   UDF_EXTENT_LENGTH_MASK) +
1118 						   UDF_EXTENT_LENGTH_MASK) &
1119 						   ~(blocksize - 1);
1120 				li->extLength = (li->extLength &
1121 						 UDF_EXTENT_FLAG_MASK) +
1122 						(UDF_EXTENT_LENGTH_MASK + 1) -
1123 						blocksize;
1124 			} else {
1125 				li->extLength = lip1->extLength +
1126 					(((li->extLength &
1127 						UDF_EXTENT_LENGTH_MASK) +
1128 					  blocksize - 1) & ~(blocksize - 1));
1129 				if (*endnum > (i + 2))
1130 					memmove(&laarr[i + 1], &laarr[i + 2],
1131 						sizeof(struct long_ad) *
1132 						(*endnum - (i + 2)));
1133 				i--;
1134 				(*endnum)--;
1135 			}
1136 		} else if ((li->extLength >> 30) ==
1137 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
1138 			udf_free_blocks(inode->i_sb, inode,
1139 					&li->extLocation, 0,
1140 					((li->extLength &
1141 						UDF_EXTENT_LENGTH_MASK) +
1142 					 blocksize - 1) >> blocksize_bits);
1143 			li->extLocation.logicalBlockNum = 0;
1144 			li->extLocation.partitionReferenceNum = 0;
1145 			li->extLength = (li->extLength &
1146 						UDF_EXTENT_LENGTH_MASK) |
1147 						EXT_NOT_RECORDED_NOT_ALLOCATED;
1148 		}
1149 	}
1150 }
1151 
1152 static void udf_update_extents(struct inode *inode,
1153 			       struct kernel_long_ad laarr[EXTENT_MERGE_SIZE],
1154 			       int startnum, int endnum,
1155 			       struct extent_position *epos)
1156 {
1157 	int start = 0, i;
1158 	struct kernel_lb_addr tmploc;
1159 	uint32_t tmplen;
1160 
1161 	if (startnum > endnum) {
1162 		for (i = 0; i < (startnum - endnum); i++)
1163 			udf_delete_aext(inode, *epos, laarr[i].extLocation,
1164 					laarr[i].extLength);
1165 	} else if (startnum < endnum) {
1166 		for (i = 0; i < (endnum - startnum); i++) {
1167 			udf_insert_aext(inode, *epos, laarr[i].extLocation,
1168 					laarr[i].extLength);
1169 			udf_next_aext(inode, epos, &laarr[i].extLocation,
1170 				      &laarr[i].extLength, 1);
1171 			start++;
1172 		}
1173 	}
1174 
1175 	for (i = start; i < endnum; i++) {
1176 		udf_next_aext(inode, epos, &tmploc, &tmplen, 0);
1177 		udf_write_aext(inode, epos, &laarr[i].extLocation,
1178 			       laarr[i].extLength, 1);
1179 	}
1180 }
1181 
1182 struct buffer_head *udf_bread(struct inode *inode, int block,
1183 			      int create, int *err)
1184 {
1185 	struct buffer_head *bh = NULL;
1186 
1187 	bh = udf_getblk(inode, block, create, err);
1188 	if (!bh)
1189 		return NULL;
1190 
1191 	if (buffer_uptodate(bh))
1192 		return bh;
1193 
1194 	ll_rw_block(READ, 1, &bh);
1195 
1196 	wait_on_buffer(bh);
1197 	if (buffer_uptodate(bh))
1198 		return bh;
1199 
1200 	brelse(bh);
1201 	*err = -EIO;
1202 	return NULL;
1203 }
1204 
1205 int udf_setsize(struct inode *inode, loff_t newsize)
1206 {
1207 	int err;
1208 	struct udf_inode_info *iinfo;
1209 	int bsize = 1 << inode->i_blkbits;
1210 
1211 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1212 	      S_ISLNK(inode->i_mode)))
1213 		return -EINVAL;
1214 	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
1215 		return -EPERM;
1216 
1217 	iinfo = UDF_I(inode);
1218 	if (newsize > inode->i_size) {
1219 		down_write(&iinfo->i_data_sem);
1220 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1221 			if (bsize <
1222 			    (udf_file_entry_alloc_offset(inode) + newsize)) {
1223 				err = udf_expand_file_adinicb(inode);
1224 				if (err)
1225 					return err;
1226 				down_write(&iinfo->i_data_sem);
1227 			} else {
1228 				iinfo->i_lenAlloc = newsize;
1229 				goto set_size;
1230 			}
1231 		}
1232 		err = udf_extend_file(inode, newsize);
1233 		if (err) {
1234 			up_write(&iinfo->i_data_sem);
1235 			return err;
1236 		}
1237 set_size:
1238 		truncate_setsize(inode, newsize);
1239 		up_write(&iinfo->i_data_sem);
1240 	} else {
1241 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1242 			down_write(&iinfo->i_data_sem);
1243 			udf_clear_extent_cache(inode);
1244 			memset(iinfo->i_ext.i_data + iinfo->i_lenEAttr + newsize,
1245 			       0x00, bsize - newsize -
1246 			       udf_file_entry_alloc_offset(inode));
1247 			iinfo->i_lenAlloc = newsize;
1248 			truncate_setsize(inode, newsize);
1249 			up_write(&iinfo->i_data_sem);
1250 			goto update_time;
1251 		}
1252 		err = block_truncate_page(inode->i_mapping, newsize,
1253 					  udf_get_block);
1254 		if (err)
1255 			return err;
1256 		down_write(&iinfo->i_data_sem);
1257 		udf_clear_extent_cache(inode);
1258 		truncate_setsize(inode, newsize);
1259 		udf_truncate_extents(inode);
1260 		up_write(&iinfo->i_data_sem);
1261 	}
1262 update_time:
1263 	inode->i_mtime = inode->i_ctime = current_fs_time(inode->i_sb);
1264 	if (IS_SYNC(inode))
1265 		udf_sync_inode(inode);
1266 	else
1267 		mark_inode_dirty(inode);
1268 	return 0;
1269 }
1270 
1271 /*
1272  * Maximum length of linked list formed by ICB hierarchy. The chosen number is
1273  * arbitrary - just that we hopefully don't limit any real use of rewritten
1274  * inode on write-once media but avoid looping for too long on corrupted media.
1275  */
1276 #define UDF_MAX_ICB_NESTING 1024
1277 
1278 static int udf_read_inode(struct inode *inode, bool hidden_inode)
1279 {
1280 	struct buffer_head *bh = NULL;
1281 	struct fileEntry *fe;
1282 	struct extendedFileEntry *efe;
1283 	uint16_t ident;
1284 	struct udf_inode_info *iinfo = UDF_I(inode);
1285 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1286 	struct kernel_lb_addr *iloc = &iinfo->i_location;
1287 	unsigned int link_count;
1288 	unsigned int indirections = 0;
1289 	int bs = inode->i_sb->s_blocksize;
1290 	int ret = -EIO;
1291 
1292 reread:
1293 	if (iloc->logicalBlockNum >=
1294 	    sbi->s_partmaps[iloc->partitionReferenceNum].s_partition_len) {
1295 		udf_debug("block=%d, partition=%d out of range\n",
1296 			  iloc->logicalBlockNum, iloc->partitionReferenceNum);
1297 		return -EIO;
1298 	}
1299 
1300 	/*
1301 	 * Set defaults, but the inode is still incomplete!
1302 	 * Note: get_new_inode() sets the following on a new inode:
1303 	 *      i_sb = sb
1304 	 *      i_no = ino
1305 	 *      i_flags = sb->s_flags
1306 	 *      i_state = 0
1307 	 * clean_inode(): zero fills and sets
1308 	 *      i_count = 1
1309 	 *      i_nlink = 1
1310 	 *      i_op = NULL;
1311 	 */
1312 	bh = udf_read_ptagged(inode->i_sb, iloc, 0, &ident);
1313 	if (!bh) {
1314 		udf_err(inode->i_sb, "(ino %ld) failed !bh\n", inode->i_ino);
1315 		return -EIO;
1316 	}
1317 
1318 	if (ident != TAG_IDENT_FE && ident != TAG_IDENT_EFE &&
1319 	    ident != TAG_IDENT_USE) {
1320 		udf_err(inode->i_sb, "(ino %ld) failed ident=%d\n",
1321 			inode->i_ino, ident);
1322 		goto out;
1323 	}
1324 
1325 	fe = (struct fileEntry *)bh->b_data;
1326 	efe = (struct extendedFileEntry *)bh->b_data;
1327 
1328 	if (fe->icbTag.strategyType == cpu_to_le16(4096)) {
1329 		struct buffer_head *ibh;
1330 
1331 		ibh = udf_read_ptagged(inode->i_sb, iloc, 1, &ident);
1332 		if (ident == TAG_IDENT_IE && ibh) {
1333 			struct kernel_lb_addr loc;
1334 			struct indirectEntry *ie;
1335 
1336 			ie = (struct indirectEntry *)ibh->b_data;
1337 			loc = lelb_to_cpu(ie->indirectICB.extLocation);
1338 
1339 			if (ie->indirectICB.extLength) {
1340 				brelse(ibh);
1341 				memcpy(&iinfo->i_location, &loc,
1342 				       sizeof(struct kernel_lb_addr));
1343 				if (++indirections > UDF_MAX_ICB_NESTING) {
1344 					udf_err(inode->i_sb,
1345 						"too many ICBs in ICB hierarchy"
1346 						" (max %d supported)\n",
1347 						UDF_MAX_ICB_NESTING);
1348 					goto out;
1349 				}
1350 				brelse(bh);
1351 				goto reread;
1352 			}
1353 		}
1354 		brelse(ibh);
1355 	} else if (fe->icbTag.strategyType != cpu_to_le16(4)) {
1356 		udf_err(inode->i_sb, "unsupported strategy type: %d\n",
1357 			le16_to_cpu(fe->icbTag.strategyType));
1358 		goto out;
1359 	}
1360 	if (fe->icbTag.strategyType == cpu_to_le16(4))
1361 		iinfo->i_strat4096 = 0;
1362 	else /* if (fe->icbTag.strategyType == cpu_to_le16(4096)) */
1363 		iinfo->i_strat4096 = 1;
1364 
1365 	iinfo->i_alloc_type = le16_to_cpu(fe->icbTag.flags) &
1366 							ICBTAG_FLAG_AD_MASK;
1367 	iinfo->i_unique = 0;
1368 	iinfo->i_lenEAttr = 0;
1369 	iinfo->i_lenExtents = 0;
1370 	iinfo->i_lenAlloc = 0;
1371 	iinfo->i_next_alloc_block = 0;
1372 	iinfo->i_next_alloc_goal = 0;
1373 	if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_EFE)) {
1374 		iinfo->i_efe = 1;
1375 		iinfo->i_use = 0;
1376 		ret = udf_alloc_i_data(inode, bs -
1377 					sizeof(struct extendedFileEntry));
1378 		if (ret)
1379 			goto out;
1380 		memcpy(iinfo->i_ext.i_data,
1381 		       bh->b_data + sizeof(struct extendedFileEntry),
1382 		       bs - sizeof(struct extendedFileEntry));
1383 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_FE)) {
1384 		iinfo->i_efe = 0;
1385 		iinfo->i_use = 0;
1386 		ret = udf_alloc_i_data(inode, bs - sizeof(struct fileEntry));
1387 		if (ret)
1388 			goto out;
1389 		memcpy(iinfo->i_ext.i_data,
1390 		       bh->b_data + sizeof(struct fileEntry),
1391 		       bs - sizeof(struct fileEntry));
1392 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_USE)) {
1393 		iinfo->i_efe = 0;
1394 		iinfo->i_use = 1;
1395 		iinfo->i_lenAlloc = le32_to_cpu(
1396 				((struct unallocSpaceEntry *)bh->b_data)->
1397 				 lengthAllocDescs);
1398 		ret = udf_alloc_i_data(inode, bs -
1399 					sizeof(struct unallocSpaceEntry));
1400 		if (ret)
1401 			goto out;
1402 		memcpy(iinfo->i_ext.i_data,
1403 		       bh->b_data + sizeof(struct unallocSpaceEntry),
1404 		       bs - sizeof(struct unallocSpaceEntry));
1405 		return 0;
1406 	}
1407 
1408 	ret = -EIO;
1409 	read_lock(&sbi->s_cred_lock);
1410 	i_uid_write(inode, le32_to_cpu(fe->uid));
1411 	if (!uid_valid(inode->i_uid) ||
1412 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_IGNORE) ||
1413 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_SET))
1414 		inode->i_uid = UDF_SB(inode->i_sb)->s_uid;
1415 
1416 	i_gid_write(inode, le32_to_cpu(fe->gid));
1417 	if (!gid_valid(inode->i_gid) ||
1418 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_IGNORE) ||
1419 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_SET))
1420 		inode->i_gid = UDF_SB(inode->i_sb)->s_gid;
1421 
1422 	if (fe->icbTag.fileType != ICBTAG_FILE_TYPE_DIRECTORY &&
1423 			sbi->s_fmode != UDF_INVALID_MODE)
1424 		inode->i_mode = sbi->s_fmode;
1425 	else if (fe->icbTag.fileType == ICBTAG_FILE_TYPE_DIRECTORY &&
1426 			sbi->s_dmode != UDF_INVALID_MODE)
1427 		inode->i_mode = sbi->s_dmode;
1428 	else
1429 		inode->i_mode = udf_convert_permissions(fe);
1430 	inode->i_mode &= ~sbi->s_umask;
1431 	read_unlock(&sbi->s_cred_lock);
1432 
1433 	link_count = le16_to_cpu(fe->fileLinkCount);
1434 	if (!link_count) {
1435 		if (!hidden_inode) {
1436 			ret = -ESTALE;
1437 			goto out;
1438 		}
1439 		link_count = 1;
1440 	}
1441 	set_nlink(inode, link_count);
1442 
1443 	inode->i_size = le64_to_cpu(fe->informationLength);
1444 	iinfo->i_lenExtents = inode->i_size;
1445 
1446 	if (iinfo->i_efe == 0) {
1447 		inode->i_blocks = le64_to_cpu(fe->logicalBlocksRecorded) <<
1448 			(inode->i_sb->s_blocksize_bits - 9);
1449 
1450 		if (!udf_disk_stamp_to_time(&inode->i_atime, fe->accessTime))
1451 			inode->i_atime = sbi->s_record_time;
1452 
1453 		if (!udf_disk_stamp_to_time(&inode->i_mtime,
1454 					    fe->modificationTime))
1455 			inode->i_mtime = sbi->s_record_time;
1456 
1457 		if (!udf_disk_stamp_to_time(&inode->i_ctime, fe->attrTime))
1458 			inode->i_ctime = sbi->s_record_time;
1459 
1460 		iinfo->i_unique = le64_to_cpu(fe->uniqueID);
1461 		iinfo->i_lenEAttr = le32_to_cpu(fe->lengthExtendedAttr);
1462 		iinfo->i_lenAlloc = le32_to_cpu(fe->lengthAllocDescs);
1463 		iinfo->i_checkpoint = le32_to_cpu(fe->checkpoint);
1464 	} else {
1465 		inode->i_blocks = le64_to_cpu(efe->logicalBlocksRecorded) <<
1466 		    (inode->i_sb->s_blocksize_bits - 9);
1467 
1468 		if (!udf_disk_stamp_to_time(&inode->i_atime, efe->accessTime))
1469 			inode->i_atime = sbi->s_record_time;
1470 
1471 		if (!udf_disk_stamp_to_time(&inode->i_mtime,
1472 					    efe->modificationTime))
1473 			inode->i_mtime = sbi->s_record_time;
1474 
1475 		if (!udf_disk_stamp_to_time(&iinfo->i_crtime, efe->createTime))
1476 			iinfo->i_crtime = sbi->s_record_time;
1477 
1478 		if (!udf_disk_stamp_to_time(&inode->i_ctime, efe->attrTime))
1479 			inode->i_ctime = sbi->s_record_time;
1480 
1481 		iinfo->i_unique = le64_to_cpu(efe->uniqueID);
1482 		iinfo->i_lenEAttr = le32_to_cpu(efe->lengthExtendedAttr);
1483 		iinfo->i_lenAlloc = le32_to_cpu(efe->lengthAllocDescs);
1484 		iinfo->i_checkpoint = le32_to_cpu(efe->checkpoint);
1485 	}
1486 	inode->i_generation = iinfo->i_unique;
1487 
1488 	/*
1489 	 * Sanity check length of allocation descriptors and extended attrs to
1490 	 * avoid integer overflows
1491 	 */
1492 	if (iinfo->i_lenEAttr > bs || iinfo->i_lenAlloc > bs)
1493 		goto out;
1494 	/* Now do exact checks */
1495 	if (udf_file_entry_alloc_offset(inode) + iinfo->i_lenAlloc > bs)
1496 		goto out;
1497 	/* Sanity checks for files in ICB so that we don't get confused later */
1498 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1499 		/*
1500 		 * For file in ICB data is stored in allocation descriptor
1501 		 * so sizes should match
1502 		 */
1503 		if (iinfo->i_lenAlloc != inode->i_size)
1504 			goto out;
1505 		/* File in ICB has to fit in there... */
1506 		if (inode->i_size > bs - udf_file_entry_alloc_offset(inode))
1507 			goto out;
1508 	}
1509 
1510 	switch (fe->icbTag.fileType) {
1511 	case ICBTAG_FILE_TYPE_DIRECTORY:
1512 		inode->i_op = &udf_dir_inode_operations;
1513 		inode->i_fop = &udf_dir_operations;
1514 		inode->i_mode |= S_IFDIR;
1515 		inc_nlink(inode);
1516 		break;
1517 	case ICBTAG_FILE_TYPE_REALTIME:
1518 	case ICBTAG_FILE_TYPE_REGULAR:
1519 	case ICBTAG_FILE_TYPE_UNDEF:
1520 	case ICBTAG_FILE_TYPE_VAT20:
1521 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1522 			inode->i_data.a_ops = &udf_adinicb_aops;
1523 		else
1524 			inode->i_data.a_ops = &udf_aops;
1525 		inode->i_op = &udf_file_inode_operations;
1526 		inode->i_fop = &udf_file_operations;
1527 		inode->i_mode |= S_IFREG;
1528 		break;
1529 	case ICBTAG_FILE_TYPE_BLOCK:
1530 		inode->i_mode |= S_IFBLK;
1531 		break;
1532 	case ICBTAG_FILE_TYPE_CHAR:
1533 		inode->i_mode |= S_IFCHR;
1534 		break;
1535 	case ICBTAG_FILE_TYPE_FIFO:
1536 		init_special_inode(inode, inode->i_mode | S_IFIFO, 0);
1537 		break;
1538 	case ICBTAG_FILE_TYPE_SOCKET:
1539 		init_special_inode(inode, inode->i_mode | S_IFSOCK, 0);
1540 		break;
1541 	case ICBTAG_FILE_TYPE_SYMLINK:
1542 		inode->i_data.a_ops = &udf_symlink_aops;
1543 		inode->i_op = &udf_symlink_inode_operations;
1544 		inode->i_mode = S_IFLNK | S_IRWXUGO;
1545 		break;
1546 	case ICBTAG_FILE_TYPE_MAIN:
1547 		udf_debug("METADATA FILE-----\n");
1548 		break;
1549 	case ICBTAG_FILE_TYPE_MIRROR:
1550 		udf_debug("METADATA MIRROR FILE-----\n");
1551 		break;
1552 	case ICBTAG_FILE_TYPE_BITMAP:
1553 		udf_debug("METADATA BITMAP FILE-----\n");
1554 		break;
1555 	default:
1556 		udf_err(inode->i_sb, "(ino %ld) failed unknown file type=%d\n",
1557 			inode->i_ino, fe->icbTag.fileType);
1558 		goto out;
1559 	}
1560 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1561 		struct deviceSpec *dsea =
1562 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1563 		if (dsea) {
1564 			init_special_inode(inode, inode->i_mode,
1565 				MKDEV(le32_to_cpu(dsea->majorDeviceIdent),
1566 				      le32_to_cpu(dsea->minorDeviceIdent)));
1567 			/* Developer ID ??? */
1568 		} else
1569 			goto out;
1570 	}
1571 	ret = 0;
1572 out:
1573 	brelse(bh);
1574 	return ret;
1575 }
1576 
1577 static int udf_alloc_i_data(struct inode *inode, size_t size)
1578 {
1579 	struct udf_inode_info *iinfo = UDF_I(inode);
1580 	iinfo->i_ext.i_data = kmalloc(size, GFP_KERNEL);
1581 
1582 	if (!iinfo->i_ext.i_data) {
1583 		udf_err(inode->i_sb, "(ino %ld) no free memory\n",
1584 			inode->i_ino);
1585 		return -ENOMEM;
1586 	}
1587 
1588 	return 0;
1589 }
1590 
1591 static umode_t udf_convert_permissions(struct fileEntry *fe)
1592 {
1593 	umode_t mode;
1594 	uint32_t permissions;
1595 	uint32_t flags;
1596 
1597 	permissions = le32_to_cpu(fe->permissions);
1598 	flags = le16_to_cpu(fe->icbTag.flags);
1599 
1600 	mode =	((permissions) & S_IRWXO) |
1601 		((permissions >> 2) & S_IRWXG) |
1602 		((permissions >> 4) & S_IRWXU) |
1603 		((flags & ICBTAG_FLAG_SETUID) ? S_ISUID : 0) |
1604 		((flags & ICBTAG_FLAG_SETGID) ? S_ISGID : 0) |
1605 		((flags & ICBTAG_FLAG_STICKY) ? S_ISVTX : 0);
1606 
1607 	return mode;
1608 }
1609 
1610 int udf_write_inode(struct inode *inode, struct writeback_control *wbc)
1611 {
1612 	return udf_update_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
1613 }
1614 
1615 static int udf_sync_inode(struct inode *inode)
1616 {
1617 	return udf_update_inode(inode, 1);
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 		use->descTag.tagLocation =
1656 				cpu_to_le32(iinfo->i_location.logicalBlockNum);
1657 		crclen = sizeof(struct unallocSpaceEntry) +
1658 				iinfo->i_lenAlloc - sizeof(struct tag);
1659 		use->descTag.descCRCLength = cpu_to_le16(crclen);
1660 		use->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)use +
1661 							   sizeof(struct tag),
1662 							   crclen));
1663 		use->descTag.tagChecksum = udf_tag_checksum(&use->descTag);
1664 
1665 		goto out;
1666 	}
1667 
1668 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_FORGET))
1669 		fe->uid = cpu_to_le32(-1);
1670 	else
1671 		fe->uid = cpu_to_le32(i_uid_read(inode));
1672 
1673 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_FORGET))
1674 		fe->gid = cpu_to_le32(-1);
1675 	else
1676 		fe->gid = cpu_to_le32(i_gid_read(inode));
1677 
1678 	udfperms = ((inode->i_mode & S_IRWXO)) |
1679 		   ((inode->i_mode & S_IRWXG) << 2) |
1680 		   ((inode->i_mode & S_IRWXU) << 4);
1681 
1682 	udfperms |= (le32_to_cpu(fe->permissions) &
1683 		    (FE_PERM_O_DELETE | FE_PERM_O_CHATTR |
1684 		     FE_PERM_G_DELETE | FE_PERM_G_CHATTR |
1685 		     FE_PERM_U_DELETE | FE_PERM_U_CHATTR));
1686 	fe->permissions = cpu_to_le32(udfperms);
1687 
1688 	if (S_ISDIR(inode->i_mode) && inode->i_nlink > 0)
1689 		fe->fileLinkCount = cpu_to_le16(inode->i_nlink - 1);
1690 	else
1691 		fe->fileLinkCount = cpu_to_le16(inode->i_nlink);
1692 
1693 	fe->informationLength = cpu_to_le64(inode->i_size);
1694 
1695 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1696 		struct regid *eid;
1697 		struct deviceSpec *dsea =
1698 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1699 		if (!dsea) {
1700 			dsea = (struct deviceSpec *)
1701 				udf_add_extendedattr(inode,
1702 						     sizeof(struct deviceSpec) +
1703 						     sizeof(struct regid), 12, 0x3);
1704 			dsea->attrType = cpu_to_le32(12);
1705 			dsea->attrSubtype = 1;
1706 			dsea->attrLength = cpu_to_le32(
1707 						sizeof(struct deviceSpec) +
1708 						sizeof(struct regid));
1709 			dsea->impUseLength = cpu_to_le32(sizeof(struct regid));
1710 		}
1711 		eid = (struct regid *)dsea->impUse;
1712 		memset(eid, 0, sizeof(struct regid));
1713 		strcpy(eid->ident, UDF_ID_DEVELOPER);
1714 		eid->identSuffix[0] = UDF_OS_CLASS_UNIX;
1715 		eid->identSuffix[1] = UDF_OS_ID_LINUX;
1716 		dsea->majorDeviceIdent = cpu_to_le32(imajor(inode));
1717 		dsea->minorDeviceIdent = cpu_to_le32(iminor(inode));
1718 	}
1719 
1720 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1721 		lb_recorded = 0; /* No extents => no blocks! */
1722 	else
1723 		lb_recorded =
1724 			(inode->i_blocks + (1 << (blocksize_bits - 9)) - 1) >>
1725 			(blocksize_bits - 9);
1726 
1727 	if (iinfo->i_efe == 0) {
1728 		memcpy(bh->b_data + sizeof(struct fileEntry),
1729 		       iinfo->i_ext.i_data,
1730 		       inode->i_sb->s_blocksize - sizeof(struct fileEntry));
1731 		fe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
1732 
1733 		udf_time_to_disk_stamp(&fe->accessTime, inode->i_atime);
1734 		udf_time_to_disk_stamp(&fe->modificationTime, inode->i_mtime);
1735 		udf_time_to_disk_stamp(&fe->attrTime, inode->i_ctime);
1736 		memset(&(fe->impIdent), 0, sizeof(struct regid));
1737 		strcpy(fe->impIdent.ident, UDF_ID_DEVELOPER);
1738 		fe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1739 		fe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1740 		fe->uniqueID = cpu_to_le64(iinfo->i_unique);
1741 		fe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
1742 		fe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1743 		fe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
1744 		fe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_FE);
1745 		crclen = sizeof(struct fileEntry);
1746 	} else {
1747 		memcpy(bh->b_data + sizeof(struct extendedFileEntry),
1748 		       iinfo->i_ext.i_data,
1749 		       inode->i_sb->s_blocksize -
1750 					sizeof(struct extendedFileEntry));
1751 		efe->objectSize = cpu_to_le64(inode->i_size);
1752 		efe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
1753 
1754 		if (iinfo->i_crtime.tv_sec > inode->i_atime.tv_sec ||
1755 		    (iinfo->i_crtime.tv_sec == inode->i_atime.tv_sec &&
1756 		     iinfo->i_crtime.tv_nsec > inode->i_atime.tv_nsec))
1757 			iinfo->i_crtime = inode->i_atime;
1758 
1759 		if (iinfo->i_crtime.tv_sec > inode->i_mtime.tv_sec ||
1760 		    (iinfo->i_crtime.tv_sec == inode->i_mtime.tv_sec &&
1761 		     iinfo->i_crtime.tv_nsec > inode->i_mtime.tv_nsec))
1762 			iinfo->i_crtime = inode->i_mtime;
1763 
1764 		if (iinfo->i_crtime.tv_sec > inode->i_ctime.tv_sec ||
1765 		    (iinfo->i_crtime.tv_sec == inode->i_ctime.tv_sec &&
1766 		     iinfo->i_crtime.tv_nsec > inode->i_ctime.tv_nsec))
1767 			iinfo->i_crtime = inode->i_ctime;
1768 
1769 		udf_time_to_disk_stamp(&efe->accessTime, inode->i_atime);
1770 		udf_time_to_disk_stamp(&efe->modificationTime, inode->i_mtime);
1771 		udf_time_to_disk_stamp(&efe->createTime, iinfo->i_crtime);
1772 		udf_time_to_disk_stamp(&efe->attrTime, inode->i_ctime);
1773 
1774 		memset(&(efe->impIdent), 0, sizeof(struct regid));
1775 		strcpy(efe->impIdent.ident, UDF_ID_DEVELOPER);
1776 		efe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1777 		efe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1778 		efe->uniqueID = cpu_to_le64(iinfo->i_unique);
1779 		efe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
1780 		efe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1781 		efe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
1782 		efe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EFE);
1783 		crclen = sizeof(struct extendedFileEntry);
1784 	}
1785 	if (iinfo->i_strat4096) {
1786 		fe->icbTag.strategyType = cpu_to_le16(4096);
1787 		fe->icbTag.strategyParameter = cpu_to_le16(1);
1788 		fe->icbTag.numEntries = cpu_to_le16(2);
1789 	} else {
1790 		fe->icbTag.strategyType = cpu_to_le16(4);
1791 		fe->icbTag.numEntries = cpu_to_le16(1);
1792 	}
1793 
1794 	if (S_ISDIR(inode->i_mode))
1795 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_DIRECTORY;
1796 	else if (S_ISREG(inode->i_mode))
1797 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_REGULAR;
1798 	else if (S_ISLNK(inode->i_mode))
1799 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SYMLINK;
1800 	else if (S_ISBLK(inode->i_mode))
1801 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_BLOCK;
1802 	else if (S_ISCHR(inode->i_mode))
1803 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_CHAR;
1804 	else if (S_ISFIFO(inode->i_mode))
1805 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_FIFO;
1806 	else if (S_ISSOCK(inode->i_mode))
1807 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SOCKET;
1808 
1809 	icbflags =	iinfo->i_alloc_type |
1810 			((inode->i_mode & S_ISUID) ? ICBTAG_FLAG_SETUID : 0) |
1811 			((inode->i_mode & S_ISGID) ? ICBTAG_FLAG_SETGID : 0) |
1812 			((inode->i_mode & S_ISVTX) ? ICBTAG_FLAG_STICKY : 0) |
1813 			(le16_to_cpu(fe->icbTag.flags) &
1814 				~(ICBTAG_FLAG_AD_MASK | ICBTAG_FLAG_SETUID |
1815 				ICBTAG_FLAG_SETGID | ICBTAG_FLAG_STICKY));
1816 
1817 	fe->icbTag.flags = cpu_to_le16(icbflags);
1818 	if (sbi->s_udfrev >= 0x0200)
1819 		fe->descTag.descVersion = cpu_to_le16(3);
1820 	else
1821 		fe->descTag.descVersion = cpu_to_le16(2);
1822 	fe->descTag.tagSerialNum = cpu_to_le16(sbi->s_serial_number);
1823 	fe->descTag.tagLocation = cpu_to_le32(
1824 					iinfo->i_location.logicalBlockNum);
1825 	crclen += iinfo->i_lenEAttr + iinfo->i_lenAlloc - sizeof(struct tag);
1826 	fe->descTag.descCRCLength = cpu_to_le16(crclen);
1827 	fe->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)fe + sizeof(struct tag),
1828 						  crclen));
1829 	fe->descTag.tagChecksum = udf_tag_checksum(&fe->descTag);
1830 
1831 out:
1832 	set_buffer_uptodate(bh);
1833 	unlock_buffer(bh);
1834 
1835 	/* write the data blocks */
1836 	mark_buffer_dirty(bh);
1837 	if (do_sync) {
1838 		sync_dirty_buffer(bh);
1839 		if (buffer_write_io_error(bh)) {
1840 			udf_warn(inode->i_sb, "IO error syncing udf inode [%08lx]\n",
1841 				 inode->i_ino);
1842 			err = -EIO;
1843 		}
1844 	}
1845 	brelse(bh);
1846 
1847 	return err;
1848 }
1849 
1850 struct inode *__udf_iget(struct super_block *sb, struct kernel_lb_addr *ino,
1851 			 bool hidden_inode)
1852 {
1853 	unsigned long block = udf_get_lb_pblock(sb, ino, 0);
1854 	struct inode *inode = iget_locked(sb, block);
1855 	int err;
1856 
1857 	if (!inode)
1858 		return ERR_PTR(-ENOMEM);
1859 
1860 	if (!(inode->i_state & I_NEW))
1861 		return inode;
1862 
1863 	memcpy(&UDF_I(inode)->i_location, ino, sizeof(struct kernel_lb_addr));
1864 	err = udf_read_inode(inode, hidden_inode);
1865 	if (err < 0) {
1866 		iget_failed(inode);
1867 		return ERR_PTR(err);
1868 	}
1869 	unlock_new_inode(inode);
1870 
1871 	return inode;
1872 }
1873 
1874 int udf_add_aext(struct inode *inode, struct extent_position *epos,
1875 		 struct kernel_lb_addr *eloc, uint32_t elen, int inc)
1876 {
1877 	int adsize;
1878 	struct short_ad *sad = NULL;
1879 	struct long_ad *lad = NULL;
1880 	struct allocExtDesc *aed;
1881 	uint8_t *ptr;
1882 	struct udf_inode_info *iinfo = UDF_I(inode);
1883 
1884 	if (!epos->bh)
1885 		ptr = iinfo->i_ext.i_data + epos->offset -
1886 			udf_file_entry_alloc_offset(inode) +
1887 			iinfo->i_lenEAttr;
1888 	else
1889 		ptr = epos->bh->b_data + epos->offset;
1890 
1891 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
1892 		adsize = sizeof(struct short_ad);
1893 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
1894 		adsize = sizeof(struct long_ad);
1895 	else
1896 		return -EIO;
1897 
1898 	if (epos->offset + (2 * adsize) > inode->i_sb->s_blocksize) {
1899 		unsigned char *sptr, *dptr;
1900 		struct buffer_head *nbh;
1901 		int err, loffset;
1902 		struct kernel_lb_addr obloc = epos->block;
1903 
1904 		epos->block.logicalBlockNum = udf_new_block(inode->i_sb, NULL,
1905 						obloc.partitionReferenceNum,
1906 						obloc.logicalBlockNum, &err);
1907 		if (!epos->block.logicalBlockNum)
1908 			return -ENOSPC;
1909 		nbh = udf_tgetblk(inode->i_sb, udf_get_lb_pblock(inode->i_sb,
1910 								 &epos->block,
1911 								 0));
1912 		if (!nbh)
1913 			return -EIO;
1914 		lock_buffer(nbh);
1915 		memset(nbh->b_data, 0x00, inode->i_sb->s_blocksize);
1916 		set_buffer_uptodate(nbh);
1917 		unlock_buffer(nbh);
1918 		mark_buffer_dirty_inode(nbh, inode);
1919 
1920 		aed = (struct allocExtDesc *)(nbh->b_data);
1921 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT))
1922 			aed->previousAllocExtLocation =
1923 					cpu_to_le32(obloc.logicalBlockNum);
1924 		if (epos->offset + adsize > inode->i_sb->s_blocksize) {
1925 			loffset = epos->offset;
1926 			aed->lengthAllocDescs = cpu_to_le32(adsize);
1927 			sptr = ptr - adsize;
1928 			dptr = nbh->b_data + sizeof(struct allocExtDesc);
1929 			memcpy(dptr, sptr, adsize);
1930 			epos->offset = sizeof(struct allocExtDesc) + adsize;
1931 		} else {
1932 			loffset = epos->offset + adsize;
1933 			aed->lengthAllocDescs = cpu_to_le32(0);
1934 			sptr = ptr;
1935 			epos->offset = sizeof(struct allocExtDesc);
1936 
1937 			if (epos->bh) {
1938 				aed = (struct allocExtDesc *)epos->bh->b_data;
1939 				le32_add_cpu(&aed->lengthAllocDescs, adsize);
1940 			} else {
1941 				iinfo->i_lenAlloc += adsize;
1942 				mark_inode_dirty(inode);
1943 			}
1944 		}
1945 		if (UDF_SB(inode->i_sb)->s_udfrev >= 0x0200)
1946 			udf_new_tag(nbh->b_data, TAG_IDENT_AED, 3, 1,
1947 				    epos->block.logicalBlockNum, sizeof(struct tag));
1948 		else
1949 			udf_new_tag(nbh->b_data, TAG_IDENT_AED, 2, 1,
1950 				    epos->block.logicalBlockNum, sizeof(struct tag));
1951 		switch (iinfo->i_alloc_type) {
1952 		case ICBTAG_FLAG_AD_SHORT:
1953 			sad = (struct short_ad *)sptr;
1954 			sad->extLength = cpu_to_le32(EXT_NEXT_EXTENT_ALLOCDECS |
1955 						     inode->i_sb->s_blocksize);
1956 			sad->extPosition =
1957 				cpu_to_le32(epos->block.logicalBlockNum);
1958 			break;
1959 		case ICBTAG_FLAG_AD_LONG:
1960 			lad = (struct long_ad *)sptr;
1961 			lad->extLength = cpu_to_le32(EXT_NEXT_EXTENT_ALLOCDECS |
1962 						     inode->i_sb->s_blocksize);
1963 			lad->extLocation = cpu_to_lelb(epos->block);
1964 			memset(lad->impUse, 0x00, sizeof(lad->impUse));
1965 			break;
1966 		}
1967 		if (epos->bh) {
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, loffset);
1971 			else
1972 				udf_update_tag(epos->bh->b_data,
1973 						sizeof(struct allocExtDesc));
1974 			mark_buffer_dirty_inode(epos->bh, inode);
1975 			brelse(epos->bh);
1976 		} else {
1977 			mark_inode_dirty(inode);
1978 		}
1979 		epos->bh = nbh;
1980 	}
1981 
1982 	udf_write_aext(inode, epos, eloc, elen, inc);
1983 
1984 	if (!epos->bh) {
1985 		iinfo->i_lenAlloc += adsize;
1986 		mark_inode_dirty(inode);
1987 	} else {
1988 		aed = (struct allocExtDesc *)epos->bh->b_data;
1989 		le32_add_cpu(&aed->lengthAllocDescs, adsize);
1990 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
1991 				UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
1992 			udf_update_tag(epos->bh->b_data,
1993 					epos->offset + (inc ? 0 : adsize));
1994 		else
1995 			udf_update_tag(epos->bh->b_data,
1996 					sizeof(struct allocExtDesc));
1997 		mark_buffer_dirty_inode(epos->bh, inode);
1998 	}
1999 
2000 	return 0;
2001 }
2002 
2003 void udf_write_aext(struct inode *inode, struct extent_position *epos,
2004 		    struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2005 {
2006 	int adsize;
2007 	uint8_t *ptr;
2008 	struct short_ad *sad;
2009 	struct long_ad *lad;
2010 	struct udf_inode_info *iinfo = UDF_I(inode);
2011 
2012 	if (!epos->bh)
2013 		ptr = iinfo->i_ext.i_data + epos->offset -
2014 			udf_file_entry_alloc_offset(inode) +
2015 			iinfo->i_lenEAttr;
2016 	else
2017 		ptr = epos->bh->b_data + epos->offset;
2018 
2019 	switch (iinfo->i_alloc_type) {
2020 	case ICBTAG_FLAG_AD_SHORT:
2021 		sad = (struct short_ad *)ptr;
2022 		sad->extLength = cpu_to_le32(elen);
2023 		sad->extPosition = cpu_to_le32(eloc->logicalBlockNum);
2024 		adsize = sizeof(struct short_ad);
2025 		break;
2026 	case ICBTAG_FLAG_AD_LONG:
2027 		lad = (struct long_ad *)ptr;
2028 		lad->extLength = cpu_to_le32(elen);
2029 		lad->extLocation = cpu_to_lelb(*eloc);
2030 		memset(lad->impUse, 0x00, sizeof(lad->impUse));
2031 		adsize = sizeof(struct long_ad);
2032 		break;
2033 	default:
2034 		return;
2035 	}
2036 
2037 	if (epos->bh) {
2038 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2039 		    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201) {
2040 			struct allocExtDesc *aed =
2041 				(struct allocExtDesc *)epos->bh->b_data;
2042 			udf_update_tag(epos->bh->b_data,
2043 				       le32_to_cpu(aed->lengthAllocDescs) +
2044 				       sizeof(struct allocExtDesc));
2045 		}
2046 		mark_buffer_dirty_inode(epos->bh, inode);
2047 	} else {
2048 		mark_inode_dirty(inode);
2049 	}
2050 
2051 	if (inc)
2052 		epos->offset += adsize;
2053 }
2054 
2055 int8_t udf_next_aext(struct inode *inode, struct extent_position *epos,
2056 		     struct kernel_lb_addr *eloc, uint32_t *elen, int inc)
2057 {
2058 	int8_t etype;
2059 
2060 	while ((etype = udf_current_aext(inode, epos, eloc, elen, inc)) ==
2061 	       (EXT_NEXT_EXTENT_ALLOCDECS >> 30)) {
2062 		int block;
2063 		epos->block = *eloc;
2064 		epos->offset = sizeof(struct allocExtDesc);
2065 		brelse(epos->bh);
2066 		block = udf_get_lb_pblock(inode->i_sb, &epos->block, 0);
2067 		epos->bh = udf_tread(inode->i_sb, block);
2068 		if (!epos->bh) {
2069 			udf_debug("reading block %d failed!\n", block);
2070 			return -1;
2071 		}
2072 	}
2073 
2074 	return etype;
2075 }
2076 
2077 int8_t udf_current_aext(struct inode *inode, struct extent_position *epos,
2078 			struct kernel_lb_addr *eloc, uint32_t *elen, int inc)
2079 {
2080 	int alen;
2081 	int8_t etype;
2082 	uint8_t *ptr;
2083 	struct short_ad *sad;
2084 	struct long_ad *lad;
2085 	struct udf_inode_info *iinfo = UDF_I(inode);
2086 
2087 	if (!epos->bh) {
2088 		if (!epos->offset)
2089 			epos->offset = udf_file_entry_alloc_offset(inode);
2090 		ptr = iinfo->i_ext.i_data + epos->offset -
2091 			udf_file_entry_alloc_offset(inode) +
2092 			iinfo->i_lenEAttr;
2093 		alen = udf_file_entry_alloc_offset(inode) +
2094 							iinfo->i_lenAlloc;
2095 	} else {
2096 		if (!epos->offset)
2097 			epos->offset = sizeof(struct allocExtDesc);
2098 		ptr = epos->bh->b_data + epos->offset;
2099 		alen = sizeof(struct allocExtDesc) +
2100 			le32_to_cpu(((struct allocExtDesc *)epos->bh->b_data)->
2101 							lengthAllocDescs);
2102 	}
2103 
2104 	switch (iinfo->i_alloc_type) {
2105 	case ICBTAG_FLAG_AD_SHORT:
2106 		sad = udf_get_fileshortad(ptr, alen, &epos->offset, inc);
2107 		if (!sad)
2108 			return -1;
2109 		etype = le32_to_cpu(sad->extLength) >> 30;
2110 		eloc->logicalBlockNum = le32_to_cpu(sad->extPosition);
2111 		eloc->partitionReferenceNum =
2112 				iinfo->i_location.partitionReferenceNum;
2113 		*elen = le32_to_cpu(sad->extLength) & UDF_EXTENT_LENGTH_MASK;
2114 		break;
2115 	case ICBTAG_FLAG_AD_LONG:
2116 		lad = udf_get_filelongad(ptr, alen, &epos->offset, inc);
2117 		if (!lad)
2118 			return -1;
2119 		etype = le32_to_cpu(lad->extLength) >> 30;
2120 		*eloc = lelb_to_cpu(lad->extLocation);
2121 		*elen = le32_to_cpu(lad->extLength) & UDF_EXTENT_LENGTH_MASK;
2122 		break;
2123 	default:
2124 		udf_debug("alloc_type = %d unsupported\n", iinfo->i_alloc_type);
2125 		return -1;
2126 	}
2127 
2128 	return etype;
2129 }
2130 
2131 static int8_t udf_insert_aext(struct inode *inode, struct extent_position epos,
2132 			      struct kernel_lb_addr neloc, uint32_t nelen)
2133 {
2134 	struct kernel_lb_addr oeloc;
2135 	uint32_t oelen;
2136 	int8_t etype;
2137 
2138 	if (epos.bh)
2139 		get_bh(epos.bh);
2140 
2141 	while ((etype = udf_next_aext(inode, &epos, &oeloc, &oelen, 0)) != -1) {
2142 		udf_write_aext(inode, &epos, &neloc, nelen, 1);
2143 		neloc = oeloc;
2144 		nelen = (etype << 30) | oelen;
2145 	}
2146 	udf_add_aext(inode, &epos, &neloc, nelen, 1);
2147 	brelse(epos.bh);
2148 
2149 	return (nelen >> 30);
2150 }
2151 
2152 int8_t udf_delete_aext(struct inode *inode, struct extent_position epos,
2153 		       struct kernel_lb_addr eloc, uint32_t elen)
2154 {
2155 	struct extent_position oepos;
2156 	int adsize;
2157 	int8_t etype;
2158 	struct allocExtDesc *aed;
2159 	struct udf_inode_info *iinfo;
2160 
2161 	if (epos.bh) {
2162 		get_bh(epos.bh);
2163 		get_bh(epos.bh);
2164 	}
2165 
2166 	iinfo = UDF_I(inode);
2167 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2168 		adsize = sizeof(struct short_ad);
2169 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2170 		adsize = sizeof(struct long_ad);
2171 	else
2172 		adsize = 0;
2173 
2174 	oepos = epos;
2175 	if (udf_next_aext(inode, &epos, &eloc, &elen, 1) == -1)
2176 		return -1;
2177 
2178 	while ((etype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1) {
2179 		udf_write_aext(inode, &oepos, &eloc, (etype << 30) | elen, 1);
2180 		if (oepos.bh != epos.bh) {
2181 			oepos.block = epos.block;
2182 			brelse(oepos.bh);
2183 			get_bh(epos.bh);
2184 			oepos.bh = epos.bh;
2185 			oepos.offset = epos.offset - adsize;
2186 		}
2187 	}
2188 	memset(&eloc, 0x00, sizeof(struct kernel_lb_addr));
2189 	elen = 0;
2190 
2191 	if (epos.bh != oepos.bh) {
2192 		udf_free_blocks(inode->i_sb, inode, &epos.block, 0, 1);
2193 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2194 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2195 		if (!oepos.bh) {
2196 			iinfo->i_lenAlloc -= (adsize * 2);
2197 			mark_inode_dirty(inode);
2198 		} else {
2199 			aed = (struct allocExtDesc *)oepos.bh->b_data;
2200 			le32_add_cpu(&aed->lengthAllocDescs, -(2 * adsize));
2201 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2202 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2203 				udf_update_tag(oepos.bh->b_data,
2204 						oepos.offset - (2 * adsize));
2205 			else
2206 				udf_update_tag(oepos.bh->b_data,
2207 						sizeof(struct allocExtDesc));
2208 			mark_buffer_dirty_inode(oepos.bh, inode);
2209 		}
2210 	} else {
2211 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2212 		if (!oepos.bh) {
2213 			iinfo->i_lenAlloc -= adsize;
2214 			mark_inode_dirty(inode);
2215 		} else {
2216 			aed = (struct allocExtDesc *)oepos.bh->b_data;
2217 			le32_add_cpu(&aed->lengthAllocDescs, -adsize);
2218 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2219 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2220 				udf_update_tag(oepos.bh->b_data,
2221 						epos.offset - adsize);
2222 			else
2223 				udf_update_tag(oepos.bh->b_data,
2224 						sizeof(struct allocExtDesc));
2225 			mark_buffer_dirty_inode(oepos.bh, inode);
2226 		}
2227 	}
2228 
2229 	brelse(epos.bh);
2230 	brelse(oepos.bh);
2231 
2232 	return (elen >> 30);
2233 }
2234 
2235 int8_t inode_bmap(struct inode *inode, sector_t block,
2236 		  struct extent_position *pos, struct kernel_lb_addr *eloc,
2237 		  uint32_t *elen, sector_t *offset)
2238 {
2239 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
2240 	loff_t lbcount = 0, bcount =
2241 	    (loff_t) block << blocksize_bits;
2242 	int8_t etype;
2243 	struct udf_inode_info *iinfo;
2244 
2245 	iinfo = UDF_I(inode);
2246 	if (!udf_read_extent_cache(inode, bcount, &lbcount, pos)) {
2247 		pos->offset = 0;
2248 		pos->block = iinfo->i_location;
2249 		pos->bh = NULL;
2250 	}
2251 	*elen = 0;
2252 	do {
2253 		etype = udf_next_aext(inode, pos, eloc, elen, 1);
2254 		if (etype == -1) {
2255 			*offset = (bcount - lbcount) >> blocksize_bits;
2256 			iinfo->i_lenExtents = lbcount;
2257 			return -1;
2258 		}
2259 		lbcount += *elen;
2260 	} while (lbcount <= bcount);
2261 	/* update extent cache */
2262 	udf_update_extent_cache(inode, lbcount - *elen, pos, 1);
2263 	*offset = (bcount + *elen - lbcount) >> blocksize_bits;
2264 
2265 	return etype;
2266 }
2267 
2268 long udf_block_map(struct inode *inode, sector_t block)
2269 {
2270 	struct kernel_lb_addr eloc;
2271 	uint32_t elen;
2272 	sector_t offset;
2273 	struct extent_position epos = {};
2274 	int ret;
2275 
2276 	down_read(&UDF_I(inode)->i_data_sem);
2277 
2278 	if (inode_bmap(inode, block, &epos, &eloc, &elen, &offset) ==
2279 						(EXT_RECORDED_ALLOCATED >> 30))
2280 		ret = udf_get_lb_pblock(inode->i_sb, &eloc, offset);
2281 	else
2282 		ret = 0;
2283 
2284 	up_read(&UDF_I(inode)->i_data_sem);
2285 	brelse(epos.bh);
2286 
2287 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_VARCONV))
2288 		return udf_fixed_to_variable(ret);
2289 	else
2290 		return ret;
2291 }
2292