xref: /linux/fs/udf/inode.c (revision 2ba9268dd603d23e17643437b2246acb6844953b)
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/buffer_head.h>
37 #include <linux/writeback.h>
38 #include <linux/slab.h>
39 #include <linux/crc-itu-t.h>
40 #include <linux/mpage.h>
41 #include <linux/aio.h>
42 
43 #include "udf_i.h"
44 #include "udf_sb.h"
45 
46 MODULE_AUTHOR("Ben Fennema");
47 MODULE_DESCRIPTION("Universal Disk Format Filesystem");
48 MODULE_LICENSE("GPL");
49 
50 #define EXTENT_MERGE_SIZE 5
51 
52 static umode_t udf_convert_permissions(struct fileEntry *);
53 static int udf_update_inode(struct inode *, int);
54 static int udf_sync_inode(struct inode *inode);
55 static int udf_alloc_i_data(struct inode *inode, size_t size);
56 static sector_t inode_getblk(struct inode *, sector_t, int *, int *);
57 static int8_t udf_insert_aext(struct inode *, struct extent_position,
58 			      struct kernel_lb_addr, uint32_t);
59 static void udf_split_extents(struct inode *, int *, int, int,
60 			      struct kernel_long_ad[EXTENT_MERGE_SIZE], int *);
61 static void udf_prealloc_extents(struct inode *, int, int,
62 				 struct kernel_long_ad[EXTENT_MERGE_SIZE], int *);
63 static void udf_merge_extents(struct inode *,
64 			      struct kernel_long_ad[EXTENT_MERGE_SIZE], int *);
65 static void udf_update_extents(struct inode *,
66 			       struct kernel_long_ad[EXTENT_MERGE_SIZE], int, int,
67 			       struct extent_position *);
68 static int udf_get_block(struct inode *, sector_t, struct buffer_head *, int);
69 
70 static void __udf_clear_extent_cache(struct inode *inode)
71 {
72 	struct udf_inode_info *iinfo = UDF_I(inode);
73 
74 	if (iinfo->cached_extent.lstart != -1) {
75 		brelse(iinfo->cached_extent.epos.bh);
76 		iinfo->cached_extent.lstart = -1;
77 	}
78 }
79 
80 /* Invalidate extent cache */
81 static void udf_clear_extent_cache(struct inode *inode)
82 {
83 	struct udf_inode_info *iinfo = UDF_I(inode);
84 
85 	spin_lock(&iinfo->i_extent_cache_lock);
86 	__udf_clear_extent_cache(inode);
87 	spin_unlock(&iinfo->i_extent_cache_lock);
88 }
89 
90 /* Return contents of extent cache */
91 static int udf_read_extent_cache(struct inode *inode, loff_t bcount,
92 				 loff_t *lbcount, struct extent_position *pos)
93 {
94 	struct udf_inode_info *iinfo = UDF_I(inode);
95 	int ret = 0;
96 
97 	spin_lock(&iinfo->i_extent_cache_lock);
98 	if ((iinfo->cached_extent.lstart <= bcount) &&
99 	    (iinfo->cached_extent.lstart != -1)) {
100 		/* Cache hit */
101 		*lbcount = iinfo->cached_extent.lstart;
102 		memcpy(pos, &iinfo->cached_extent.epos,
103 		       sizeof(struct extent_position));
104 		if (pos->bh)
105 			get_bh(pos->bh);
106 		ret = 1;
107 	}
108 	spin_unlock(&iinfo->i_extent_cache_lock);
109 	return ret;
110 }
111 
112 /* Add extent to extent cache */
113 static void udf_update_extent_cache(struct inode *inode, loff_t estart,
114 				    struct extent_position *pos, int next_epos)
115 {
116 	struct udf_inode_info *iinfo = UDF_I(inode);
117 
118 	spin_lock(&iinfo->i_extent_cache_lock);
119 	/* Invalidate previously cached extent */
120 	__udf_clear_extent_cache(inode);
121 	if (pos->bh)
122 		get_bh(pos->bh);
123 	memcpy(&iinfo->cached_extent.epos, pos,
124 	       sizeof(struct extent_position));
125 	iinfo->cached_extent.lstart = estart;
126 	if (next_epos)
127 		switch (iinfo->i_alloc_type) {
128 		case ICBTAG_FLAG_AD_SHORT:
129 			iinfo->cached_extent.epos.offset -=
130 			sizeof(struct short_ad);
131 			break;
132 		case ICBTAG_FLAG_AD_LONG:
133 			iinfo->cached_extent.epos.offset -=
134 			sizeof(struct long_ad);
135 		}
136 	spin_unlock(&iinfo->i_extent_cache_lock);
137 }
138 
139 void udf_evict_inode(struct inode *inode)
140 {
141 	struct udf_inode_info *iinfo = UDF_I(inode);
142 	int want_delete = 0;
143 
144 	if (!inode->i_nlink && !is_bad_inode(inode)) {
145 		want_delete = 1;
146 		udf_setsize(inode, 0);
147 		udf_update_inode(inode, IS_SYNC(inode));
148 	}
149 	truncate_inode_pages_final(&inode->i_data);
150 	invalidate_inode_buffers(inode);
151 	clear_inode(inode);
152 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB &&
153 	    inode->i_size != iinfo->i_lenExtents) {
154 		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",
155 			 inode->i_ino, inode->i_mode,
156 			 (unsigned long long)inode->i_size,
157 			 (unsigned long long)iinfo->i_lenExtents);
158 	}
159 	kfree(iinfo->i_ext.i_data);
160 	iinfo->i_ext.i_data = NULL;
161 	udf_clear_extent_cache(inode);
162 	if (want_delete) {
163 		udf_free_inode(inode);
164 	}
165 }
166 
167 static void udf_write_failed(struct address_space *mapping, loff_t to)
168 {
169 	struct inode *inode = mapping->host;
170 	struct udf_inode_info *iinfo = UDF_I(inode);
171 	loff_t isize = inode->i_size;
172 
173 	if (to > isize) {
174 		truncate_pagecache(inode, isize);
175 		if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
176 			down_write(&iinfo->i_data_sem);
177 			udf_clear_extent_cache(inode);
178 			udf_truncate_extents(inode);
179 			up_write(&iinfo->i_data_sem);
180 		}
181 	}
182 }
183 
184 static int udf_writepage(struct page *page, struct writeback_control *wbc)
185 {
186 	return block_write_full_page(page, udf_get_block, wbc);
187 }
188 
189 static int udf_writepages(struct address_space *mapping,
190 			struct writeback_control *wbc)
191 {
192 	return mpage_writepages(mapping, wbc, udf_get_block);
193 }
194 
195 static int udf_readpage(struct file *file, struct page *page)
196 {
197 	return mpage_readpage(page, udf_get_block);
198 }
199 
200 static int udf_readpages(struct file *file, struct address_space *mapping,
201 			struct list_head *pages, unsigned nr_pages)
202 {
203 	return mpage_readpages(mapping, pages, nr_pages, udf_get_block);
204 }
205 
206 static int udf_write_begin(struct file *file, struct address_space *mapping,
207 			loff_t pos, unsigned len, unsigned flags,
208 			struct page **pagep, void **fsdata)
209 {
210 	int ret;
211 
212 	ret = block_write_begin(mapping, pos, len, flags, pagep, udf_get_block);
213 	if (unlikely(ret))
214 		udf_write_failed(mapping, pos + len);
215 	return ret;
216 }
217 
218 static ssize_t udf_direct_IO(int rw, struct kiocb *iocb,
219 			     struct iov_iter *iter,
220 			     loff_t offset)
221 {
222 	struct file *file = iocb->ki_filp;
223 	struct address_space *mapping = file->f_mapping;
224 	struct inode *inode = mapping->host;
225 	size_t count = iov_iter_count(iter);
226 	ssize_t ret;
227 
228 	ret = blockdev_direct_IO(rw, iocb, inode, iter, offset, udf_get_block);
229 	if (unlikely(ret < 0 && (rw & WRITE)))
230 		udf_write_failed(mapping, offset + count);
231 	return ret;
232 }
233 
234 static sector_t udf_bmap(struct address_space *mapping, sector_t block)
235 {
236 	return generic_block_bmap(mapping, block, udf_get_block);
237 }
238 
239 const struct address_space_operations udf_aops = {
240 	.readpage	= udf_readpage,
241 	.readpages	= udf_readpages,
242 	.writepage	= udf_writepage,
243 	.writepages	= udf_writepages,
244 	.write_begin	= udf_write_begin,
245 	.write_end	= generic_write_end,
246 	.direct_IO	= udf_direct_IO,
247 	.bmap		= udf_bmap,
248 };
249 
250 /*
251  * Expand file stored in ICB to a normal one-block-file
252  *
253  * This function requires i_data_sem for writing and releases it.
254  * This function requires i_mutex held
255  */
256 int udf_expand_file_adinicb(struct inode *inode)
257 {
258 	struct page *page;
259 	char *kaddr;
260 	struct udf_inode_info *iinfo = UDF_I(inode);
261 	int err;
262 	struct writeback_control udf_wbc = {
263 		.sync_mode = WB_SYNC_NONE,
264 		.nr_to_write = 1,
265 	};
266 
267 	WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
268 	if (!iinfo->i_lenAlloc) {
269 		if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
270 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
271 		else
272 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
273 		/* from now on we have normal address_space methods */
274 		inode->i_data.a_ops = &udf_aops;
275 		up_write(&iinfo->i_data_sem);
276 		mark_inode_dirty(inode);
277 		return 0;
278 	}
279 	/*
280 	 * Release i_data_sem so that we can lock a page - page lock ranks
281 	 * above i_data_sem. i_mutex still protects us against file changes.
282 	 */
283 	up_write(&iinfo->i_data_sem);
284 
285 	page = find_or_create_page(inode->i_mapping, 0, GFP_NOFS);
286 	if (!page)
287 		return -ENOMEM;
288 
289 	if (!PageUptodate(page)) {
290 		kaddr = kmap(page);
291 		memset(kaddr + iinfo->i_lenAlloc, 0x00,
292 		       PAGE_CACHE_SIZE - iinfo->i_lenAlloc);
293 		memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr,
294 			iinfo->i_lenAlloc);
295 		flush_dcache_page(page);
296 		SetPageUptodate(page);
297 		kunmap(page);
298 	}
299 	down_write(&iinfo->i_data_sem);
300 	memset(iinfo->i_ext.i_data + iinfo->i_lenEAttr, 0x00,
301 	       iinfo->i_lenAlloc);
302 	iinfo->i_lenAlloc = 0;
303 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
304 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
305 	else
306 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
307 	/* from now on we have normal address_space methods */
308 	inode->i_data.a_ops = &udf_aops;
309 	up_write(&iinfo->i_data_sem);
310 	err = inode->i_data.a_ops->writepage(page, &udf_wbc);
311 	if (err) {
312 		/* Restore everything back so that we don't lose data... */
313 		lock_page(page);
314 		kaddr = kmap(page);
315 		down_write(&iinfo->i_data_sem);
316 		memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr, kaddr,
317 		       inode->i_size);
318 		kunmap(page);
319 		unlock_page(page);
320 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
321 		inode->i_data.a_ops = &udf_adinicb_aops;
322 		up_write(&iinfo->i_data_sem);
323 	}
324 	page_cache_release(page);
325 	mark_inode_dirty(inode);
326 
327 	return err;
328 }
329 
330 struct buffer_head *udf_expand_dir_adinicb(struct inode *inode, int *block,
331 					   int *err)
332 {
333 	int newblock;
334 	struct buffer_head *dbh = NULL;
335 	struct kernel_lb_addr eloc;
336 	uint8_t alloctype;
337 	struct extent_position epos;
338 
339 	struct udf_fileident_bh sfibh, dfibh;
340 	loff_t f_pos = udf_ext0_offset(inode);
341 	int size = udf_ext0_offset(inode) + inode->i_size;
342 	struct fileIdentDesc cfi, *sfi, *dfi;
343 	struct udf_inode_info *iinfo = UDF_I(inode);
344 
345 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
346 		alloctype = ICBTAG_FLAG_AD_SHORT;
347 	else
348 		alloctype = ICBTAG_FLAG_AD_LONG;
349 
350 	if (!inode->i_size) {
351 		iinfo->i_alloc_type = alloctype;
352 		mark_inode_dirty(inode);
353 		return NULL;
354 	}
355 
356 	/* alloc block, and copy data to it */
357 	*block = udf_new_block(inode->i_sb, inode,
358 			       iinfo->i_location.partitionReferenceNum,
359 			       iinfo->i_location.logicalBlockNum, err);
360 	if (!(*block))
361 		return NULL;
362 	newblock = udf_get_pblock(inode->i_sb, *block,
363 				  iinfo->i_location.partitionReferenceNum,
364 				0);
365 	if (!newblock)
366 		return NULL;
367 	dbh = udf_tgetblk(inode->i_sb, newblock);
368 	if (!dbh)
369 		return NULL;
370 	lock_buffer(dbh);
371 	memset(dbh->b_data, 0x00, inode->i_sb->s_blocksize);
372 	set_buffer_uptodate(dbh);
373 	unlock_buffer(dbh);
374 	mark_buffer_dirty_inode(dbh, inode);
375 
376 	sfibh.soffset = sfibh.eoffset =
377 			f_pos & (inode->i_sb->s_blocksize - 1);
378 	sfibh.sbh = sfibh.ebh = NULL;
379 	dfibh.soffset = dfibh.eoffset = 0;
380 	dfibh.sbh = dfibh.ebh = dbh;
381 	while (f_pos < size) {
382 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
383 		sfi = udf_fileident_read(inode, &f_pos, &sfibh, &cfi, NULL,
384 					 NULL, NULL, NULL);
385 		if (!sfi) {
386 			brelse(dbh);
387 			return NULL;
388 		}
389 		iinfo->i_alloc_type = alloctype;
390 		sfi->descTag.tagLocation = cpu_to_le32(*block);
391 		dfibh.soffset = dfibh.eoffset;
392 		dfibh.eoffset += (sfibh.eoffset - sfibh.soffset);
393 		dfi = (struct fileIdentDesc *)(dbh->b_data + dfibh.soffset);
394 		if (udf_write_fi(inode, sfi, dfi, &dfibh, sfi->impUse,
395 				 sfi->fileIdent +
396 					le16_to_cpu(sfi->lengthOfImpUse))) {
397 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
398 			brelse(dbh);
399 			return NULL;
400 		}
401 	}
402 	mark_buffer_dirty_inode(dbh, inode);
403 
404 	memset(iinfo->i_ext.i_data + iinfo->i_lenEAttr, 0,
405 		iinfo->i_lenAlloc);
406 	iinfo->i_lenAlloc = 0;
407 	eloc.logicalBlockNum = *block;
408 	eloc.partitionReferenceNum =
409 				iinfo->i_location.partitionReferenceNum;
410 	iinfo->i_lenExtents = inode->i_size;
411 	epos.bh = NULL;
412 	epos.block = iinfo->i_location;
413 	epos.offset = udf_file_entry_alloc_offset(inode);
414 	udf_add_aext(inode, &epos, &eloc, inode->i_size, 0);
415 	/* UniqueID stuff */
416 
417 	brelse(epos.bh);
418 	mark_inode_dirty(inode);
419 	return dbh;
420 }
421 
422 static int udf_get_block(struct inode *inode, sector_t block,
423 			 struct buffer_head *bh_result, int create)
424 {
425 	int err, new;
426 	sector_t phys = 0;
427 	struct udf_inode_info *iinfo;
428 
429 	if (!create) {
430 		phys = udf_block_map(inode, block);
431 		if (phys)
432 			map_bh(bh_result, inode->i_sb, phys);
433 		return 0;
434 	}
435 
436 	err = -EIO;
437 	new = 0;
438 	iinfo = UDF_I(inode);
439 
440 	down_write(&iinfo->i_data_sem);
441 	if (block == iinfo->i_next_alloc_block + 1) {
442 		iinfo->i_next_alloc_block++;
443 		iinfo->i_next_alloc_goal++;
444 	}
445 
446 	udf_clear_extent_cache(inode);
447 	phys = inode_getblk(inode, block, &err, &new);
448 	if (!phys)
449 		goto abort;
450 
451 	if (new)
452 		set_buffer_new(bh_result);
453 	map_bh(bh_result, inode->i_sb, phys);
454 
455 abort:
456 	up_write(&iinfo->i_data_sem);
457 	return err;
458 }
459 
460 static struct buffer_head *udf_getblk(struct inode *inode, long block,
461 				      int create, int *err)
462 {
463 	struct buffer_head *bh;
464 	struct buffer_head dummy;
465 
466 	dummy.b_state = 0;
467 	dummy.b_blocknr = -1000;
468 	*err = udf_get_block(inode, block, &dummy, create);
469 	if (!*err && buffer_mapped(&dummy)) {
470 		bh = sb_getblk(inode->i_sb, dummy.b_blocknr);
471 		if (buffer_new(&dummy)) {
472 			lock_buffer(bh);
473 			memset(bh->b_data, 0x00, inode->i_sb->s_blocksize);
474 			set_buffer_uptodate(bh);
475 			unlock_buffer(bh);
476 			mark_buffer_dirty_inode(bh, inode);
477 		}
478 		return bh;
479 	}
480 
481 	return NULL;
482 }
483 
484 /* Extend the file by 'blocks' blocks, return the number of extents added */
485 static int udf_do_extend_file(struct inode *inode,
486 			      struct extent_position *last_pos,
487 			      struct kernel_long_ad *last_ext,
488 			      sector_t blocks)
489 {
490 	sector_t add;
491 	int count = 0, fake = !(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
492 	struct super_block *sb = inode->i_sb;
493 	struct kernel_lb_addr prealloc_loc = {};
494 	int prealloc_len = 0;
495 	struct udf_inode_info *iinfo;
496 	int err;
497 
498 	/* The previous extent is fake and we should not extend by anything
499 	 * - there's nothing to do... */
500 	if (!blocks && fake)
501 		return 0;
502 
503 	iinfo = UDF_I(inode);
504 	/* Round the last extent up to a multiple of block size */
505 	if (last_ext->extLength & (sb->s_blocksize - 1)) {
506 		last_ext->extLength =
507 			(last_ext->extLength & UDF_EXTENT_FLAG_MASK) |
508 			(((last_ext->extLength & UDF_EXTENT_LENGTH_MASK) +
509 			  sb->s_blocksize - 1) & ~(sb->s_blocksize - 1));
510 		iinfo->i_lenExtents =
511 			(iinfo->i_lenExtents + sb->s_blocksize - 1) &
512 			~(sb->s_blocksize - 1);
513 	}
514 
515 	/* Last extent are just preallocated blocks? */
516 	if ((last_ext->extLength & UDF_EXTENT_FLAG_MASK) ==
517 						EXT_NOT_RECORDED_ALLOCATED) {
518 		/* Save the extent so that we can reattach it to the end */
519 		prealloc_loc = last_ext->extLocation;
520 		prealloc_len = last_ext->extLength;
521 		/* Mark the extent as a hole */
522 		last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
523 			(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
524 		last_ext->extLocation.logicalBlockNum = 0;
525 		last_ext->extLocation.partitionReferenceNum = 0;
526 	}
527 
528 	/* Can we merge with the previous extent? */
529 	if ((last_ext->extLength & UDF_EXTENT_FLAG_MASK) ==
530 					EXT_NOT_RECORDED_NOT_ALLOCATED) {
531 		add = ((1 << 30) - sb->s_blocksize -
532 			(last_ext->extLength & UDF_EXTENT_LENGTH_MASK)) >>
533 			sb->s_blocksize_bits;
534 		if (add > blocks)
535 			add = blocks;
536 		blocks -= add;
537 		last_ext->extLength += add << sb->s_blocksize_bits;
538 	}
539 
540 	if (fake) {
541 		udf_add_aext(inode, last_pos, &last_ext->extLocation,
542 			     last_ext->extLength, 1);
543 		count++;
544 	} else
545 		udf_write_aext(inode, last_pos, &last_ext->extLocation,
546 				last_ext->extLength, 1);
547 
548 	/* Managed to do everything necessary? */
549 	if (!blocks)
550 		goto out;
551 
552 	/* All further extents will be NOT_RECORDED_NOT_ALLOCATED */
553 	last_ext->extLocation.logicalBlockNum = 0;
554 	last_ext->extLocation.partitionReferenceNum = 0;
555 	add = (1 << (30-sb->s_blocksize_bits)) - 1;
556 	last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
557 				(add << sb->s_blocksize_bits);
558 
559 	/* Create enough extents to cover the whole hole */
560 	while (blocks > add) {
561 		blocks -= add;
562 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
563 				   last_ext->extLength, 1);
564 		if (err)
565 			return err;
566 		count++;
567 	}
568 	if (blocks) {
569 		last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
570 			(blocks << sb->s_blocksize_bits);
571 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
572 				   last_ext->extLength, 1);
573 		if (err)
574 			return err;
575 		count++;
576 	}
577 
578 out:
579 	/* Do we have some preallocated blocks saved? */
580 	if (prealloc_len) {
581 		err = udf_add_aext(inode, last_pos, &prealloc_loc,
582 				   prealloc_len, 1);
583 		if (err)
584 			return err;
585 		last_ext->extLocation = prealloc_loc;
586 		last_ext->extLength = prealloc_len;
587 		count++;
588 	}
589 
590 	/* last_pos should point to the last written extent... */
591 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
592 		last_pos->offset -= sizeof(struct short_ad);
593 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
594 		last_pos->offset -= sizeof(struct long_ad);
595 	else
596 		return -EIO;
597 
598 	return count;
599 }
600 
601 static int udf_extend_file(struct inode *inode, loff_t newsize)
602 {
603 
604 	struct extent_position epos;
605 	struct kernel_lb_addr eloc;
606 	uint32_t elen;
607 	int8_t etype;
608 	struct super_block *sb = inode->i_sb;
609 	sector_t first_block = newsize >> sb->s_blocksize_bits, offset;
610 	int adsize;
611 	struct udf_inode_info *iinfo = UDF_I(inode);
612 	struct kernel_long_ad extent;
613 	int err;
614 
615 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
616 		adsize = sizeof(struct short_ad);
617 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
618 		adsize = sizeof(struct long_ad);
619 	else
620 		BUG();
621 
622 	etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset);
623 
624 	/* File has extent covering the new size (could happen when extending
625 	 * inside a block)? */
626 	if (etype != -1)
627 		return 0;
628 	if (newsize & (sb->s_blocksize - 1))
629 		offset++;
630 	/* Extended file just to the boundary of the last file block? */
631 	if (offset == 0)
632 		return 0;
633 
634 	/* Truncate is extending the file by 'offset' blocks */
635 	if ((!epos.bh && epos.offset == udf_file_entry_alloc_offset(inode)) ||
636 	    (epos.bh && epos.offset == sizeof(struct allocExtDesc))) {
637 		/* File has no extents at all or has empty last
638 		 * indirect extent! Create a fake extent... */
639 		extent.extLocation.logicalBlockNum = 0;
640 		extent.extLocation.partitionReferenceNum = 0;
641 		extent.extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
642 	} else {
643 		epos.offset -= adsize;
644 		etype = udf_next_aext(inode, &epos, &extent.extLocation,
645 				      &extent.extLength, 0);
646 		extent.extLength |= etype << 30;
647 	}
648 	err = udf_do_extend_file(inode, &epos, &extent, offset);
649 	if (err < 0)
650 		goto out;
651 	err = 0;
652 	iinfo->i_lenExtents = newsize;
653 out:
654 	brelse(epos.bh);
655 	return err;
656 }
657 
658 static sector_t inode_getblk(struct inode *inode, sector_t block,
659 			     int *err, int *new)
660 {
661 	struct kernel_long_ad laarr[EXTENT_MERGE_SIZE];
662 	struct extent_position prev_epos, cur_epos, next_epos;
663 	int count = 0, startnum = 0, endnum = 0;
664 	uint32_t elen = 0, tmpelen;
665 	struct kernel_lb_addr eloc, tmpeloc;
666 	int c = 1;
667 	loff_t lbcount = 0, b_off = 0;
668 	uint32_t newblocknum, newblock;
669 	sector_t offset = 0;
670 	int8_t etype;
671 	struct udf_inode_info *iinfo = UDF_I(inode);
672 	int goal = 0, pgoal = iinfo->i_location.logicalBlockNum;
673 	int lastblock = 0;
674 	bool isBeyondEOF;
675 
676 	*err = 0;
677 	*new = 0;
678 	prev_epos.offset = udf_file_entry_alloc_offset(inode);
679 	prev_epos.block = iinfo->i_location;
680 	prev_epos.bh = NULL;
681 	cur_epos = next_epos = prev_epos;
682 	b_off = (loff_t)block << inode->i_sb->s_blocksize_bits;
683 
684 	/* find the extent which contains the block we are looking for.
685 	   alternate between laarr[0] and laarr[1] for locations of the
686 	   current extent, and the previous extent */
687 	do {
688 		if (prev_epos.bh != cur_epos.bh) {
689 			brelse(prev_epos.bh);
690 			get_bh(cur_epos.bh);
691 			prev_epos.bh = cur_epos.bh;
692 		}
693 		if (cur_epos.bh != next_epos.bh) {
694 			brelse(cur_epos.bh);
695 			get_bh(next_epos.bh);
696 			cur_epos.bh = next_epos.bh;
697 		}
698 
699 		lbcount += elen;
700 
701 		prev_epos.block = cur_epos.block;
702 		cur_epos.block = next_epos.block;
703 
704 		prev_epos.offset = cur_epos.offset;
705 		cur_epos.offset = next_epos.offset;
706 
707 		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 1);
708 		if (etype == -1)
709 			break;
710 
711 		c = !c;
712 
713 		laarr[c].extLength = (etype << 30) | elen;
714 		laarr[c].extLocation = eloc;
715 
716 		if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
717 			pgoal = eloc.logicalBlockNum +
718 				((elen + inode->i_sb->s_blocksize - 1) >>
719 				 inode->i_sb->s_blocksize_bits);
720 
721 		count++;
722 	} while (lbcount + elen <= b_off);
723 
724 	b_off -= lbcount;
725 	offset = b_off >> inode->i_sb->s_blocksize_bits;
726 	/*
727 	 * Move prev_epos and cur_epos into indirect extent if we are at
728 	 * the pointer to it
729 	 */
730 	udf_next_aext(inode, &prev_epos, &tmpeloc, &tmpelen, 0);
731 	udf_next_aext(inode, &cur_epos, &tmpeloc, &tmpelen, 0);
732 
733 	/* if the extent is allocated and recorded, return the block
734 	   if the extent is not a multiple of the blocksize, round up */
735 
736 	if (etype == (EXT_RECORDED_ALLOCATED >> 30)) {
737 		if (elen & (inode->i_sb->s_blocksize - 1)) {
738 			elen = EXT_RECORDED_ALLOCATED |
739 				((elen + inode->i_sb->s_blocksize - 1) &
740 				 ~(inode->i_sb->s_blocksize - 1));
741 			udf_write_aext(inode, &cur_epos, &eloc, elen, 1);
742 		}
743 		brelse(prev_epos.bh);
744 		brelse(cur_epos.bh);
745 		brelse(next_epos.bh);
746 		newblock = udf_get_lb_pblock(inode->i_sb, &eloc, offset);
747 		return newblock;
748 	}
749 
750 	/* Are we beyond EOF? */
751 	if (etype == -1) {
752 		int ret;
753 		isBeyondEOF = true;
754 		if (count) {
755 			if (c)
756 				laarr[0] = laarr[1];
757 			startnum = 1;
758 		} else {
759 			/* Create a fake extent when there's not one */
760 			memset(&laarr[0].extLocation, 0x00,
761 				sizeof(struct kernel_lb_addr));
762 			laarr[0].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
763 			/* Will udf_do_extend_file() create real extent from
764 			   a fake one? */
765 			startnum = (offset > 0);
766 		}
767 		/* Create extents for the hole between EOF and offset */
768 		ret = udf_do_extend_file(inode, &prev_epos, laarr, offset);
769 		if (ret < 0) {
770 			brelse(prev_epos.bh);
771 			brelse(cur_epos.bh);
772 			brelse(next_epos.bh);
773 			*err = ret;
774 			return 0;
775 		}
776 		c = 0;
777 		offset = 0;
778 		count += ret;
779 		/* We are not covered by a preallocated extent? */
780 		if ((laarr[0].extLength & UDF_EXTENT_FLAG_MASK) !=
781 						EXT_NOT_RECORDED_ALLOCATED) {
782 			/* Is there any real extent? - otherwise we overwrite
783 			 * the fake one... */
784 			if (count)
785 				c = !c;
786 			laarr[c].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
787 				inode->i_sb->s_blocksize;
788 			memset(&laarr[c].extLocation, 0x00,
789 				sizeof(struct kernel_lb_addr));
790 			count++;
791 		}
792 		endnum = c + 1;
793 		lastblock = 1;
794 	} else {
795 		isBeyondEOF = false;
796 		endnum = startnum = ((count > 2) ? 2 : count);
797 
798 		/* if the current extent is in position 0,
799 		   swap it with the previous */
800 		if (!c && count != 1) {
801 			laarr[2] = laarr[0];
802 			laarr[0] = laarr[1];
803 			laarr[1] = laarr[2];
804 			c = 1;
805 		}
806 
807 		/* if the current block is located in an extent,
808 		   read the next extent */
809 		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 0);
810 		if (etype != -1) {
811 			laarr[c + 1].extLength = (etype << 30) | elen;
812 			laarr[c + 1].extLocation = eloc;
813 			count++;
814 			startnum++;
815 			endnum++;
816 		} else
817 			lastblock = 1;
818 	}
819 
820 	/* if the current extent is not recorded but allocated, get the
821 	 * block in the extent corresponding to the requested block */
822 	if ((laarr[c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30))
823 		newblocknum = laarr[c].extLocation.logicalBlockNum + offset;
824 	else { /* otherwise, allocate a new block */
825 		if (iinfo->i_next_alloc_block == block)
826 			goal = iinfo->i_next_alloc_goal;
827 
828 		if (!goal) {
829 			if (!(goal = pgoal)) /* XXX: what was intended here? */
830 				goal = iinfo->i_location.logicalBlockNum + 1;
831 		}
832 
833 		newblocknum = udf_new_block(inode->i_sb, inode,
834 				iinfo->i_location.partitionReferenceNum,
835 				goal, err);
836 		if (!newblocknum) {
837 			brelse(prev_epos.bh);
838 			brelse(cur_epos.bh);
839 			brelse(next_epos.bh);
840 			*err = -ENOSPC;
841 			return 0;
842 		}
843 		if (isBeyondEOF)
844 			iinfo->i_lenExtents += inode->i_sb->s_blocksize;
845 	}
846 
847 	/* if the extent the requsted block is located in contains multiple
848 	 * blocks, split the extent into at most three extents. blocks prior
849 	 * to requested block, requested block, and blocks after requested
850 	 * block */
851 	udf_split_extents(inode, &c, offset, newblocknum, laarr, &endnum);
852 
853 #ifdef UDF_PREALLOCATE
854 	/* We preallocate blocks only for regular files. It also makes sense
855 	 * for directories but there's a problem when to drop the
856 	 * preallocation. We might use some delayed work for that but I feel
857 	 * it's overengineering for a filesystem like UDF. */
858 	if (S_ISREG(inode->i_mode))
859 		udf_prealloc_extents(inode, c, lastblock, laarr, &endnum);
860 #endif
861 
862 	/* merge any continuous blocks in laarr */
863 	udf_merge_extents(inode, laarr, &endnum);
864 
865 	/* write back the new extents, inserting new extents if the new number
866 	 * of extents is greater than the old number, and deleting extents if
867 	 * the new number of extents is less than the old number */
868 	udf_update_extents(inode, laarr, startnum, endnum, &prev_epos);
869 
870 	brelse(prev_epos.bh);
871 	brelse(cur_epos.bh);
872 	brelse(next_epos.bh);
873 
874 	newblock = udf_get_pblock(inode->i_sb, newblocknum,
875 				iinfo->i_location.partitionReferenceNum, 0);
876 	if (!newblock) {
877 		*err = -EIO;
878 		return 0;
879 	}
880 	*new = 1;
881 	iinfo->i_next_alloc_block = block;
882 	iinfo->i_next_alloc_goal = newblocknum;
883 	inode->i_ctime = current_fs_time(inode->i_sb);
884 
885 	if (IS_SYNC(inode))
886 		udf_sync_inode(inode);
887 	else
888 		mark_inode_dirty(inode);
889 
890 	return newblock;
891 }
892 
893 static void udf_split_extents(struct inode *inode, int *c, int offset,
894 			      int newblocknum,
895 			      struct kernel_long_ad laarr[EXTENT_MERGE_SIZE],
896 			      int *endnum)
897 {
898 	unsigned long blocksize = inode->i_sb->s_blocksize;
899 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
900 
901 	if ((laarr[*c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30) ||
902 	    (laarr[*c].extLength >> 30) ==
903 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
904 		int curr = *c;
905 		int blen = ((laarr[curr].extLength & UDF_EXTENT_LENGTH_MASK) +
906 			    blocksize - 1) >> blocksize_bits;
907 		int8_t etype = (laarr[curr].extLength >> 30);
908 
909 		if (blen == 1)
910 			;
911 		else if (!offset || blen == offset + 1) {
912 			laarr[curr + 2] = laarr[curr + 1];
913 			laarr[curr + 1] = laarr[curr];
914 		} else {
915 			laarr[curr + 3] = laarr[curr + 1];
916 			laarr[curr + 2] = laarr[curr + 1] = laarr[curr];
917 		}
918 
919 		if (offset) {
920 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
921 				udf_free_blocks(inode->i_sb, inode,
922 						&laarr[curr].extLocation,
923 						0, offset);
924 				laarr[curr].extLength =
925 					EXT_NOT_RECORDED_NOT_ALLOCATED |
926 					(offset << blocksize_bits);
927 				laarr[curr].extLocation.logicalBlockNum = 0;
928 				laarr[curr].extLocation.
929 						partitionReferenceNum = 0;
930 			} else
931 				laarr[curr].extLength = (etype << 30) |
932 					(offset << blocksize_bits);
933 			curr++;
934 			(*c)++;
935 			(*endnum)++;
936 		}
937 
938 		laarr[curr].extLocation.logicalBlockNum = newblocknum;
939 		if (etype == (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
940 			laarr[curr].extLocation.partitionReferenceNum =
941 				UDF_I(inode)->i_location.partitionReferenceNum;
942 		laarr[curr].extLength = EXT_RECORDED_ALLOCATED |
943 			blocksize;
944 		curr++;
945 
946 		if (blen != offset + 1) {
947 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
948 				laarr[curr].extLocation.logicalBlockNum +=
949 								offset + 1;
950 			laarr[curr].extLength = (etype << 30) |
951 				((blen - (offset + 1)) << blocksize_bits);
952 			curr++;
953 			(*endnum)++;
954 		}
955 	}
956 }
957 
958 static void udf_prealloc_extents(struct inode *inode, int c, int lastblock,
959 				 struct kernel_long_ad laarr[EXTENT_MERGE_SIZE],
960 				 int *endnum)
961 {
962 	int start, length = 0, currlength = 0, i;
963 
964 	if (*endnum >= (c + 1)) {
965 		if (!lastblock)
966 			return;
967 		else
968 			start = c;
969 	} else {
970 		if ((laarr[c + 1].extLength >> 30) ==
971 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
972 			start = c + 1;
973 			length = currlength =
974 				(((laarr[c + 1].extLength &
975 					UDF_EXTENT_LENGTH_MASK) +
976 				inode->i_sb->s_blocksize - 1) >>
977 				inode->i_sb->s_blocksize_bits);
978 		} else
979 			start = c;
980 	}
981 
982 	for (i = start + 1; i <= *endnum; i++) {
983 		if (i == *endnum) {
984 			if (lastblock)
985 				length += UDF_DEFAULT_PREALLOC_BLOCKS;
986 		} else if ((laarr[i].extLength >> 30) ==
987 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
988 			length += (((laarr[i].extLength &
989 						UDF_EXTENT_LENGTH_MASK) +
990 				    inode->i_sb->s_blocksize - 1) >>
991 				    inode->i_sb->s_blocksize_bits);
992 		} else
993 			break;
994 	}
995 
996 	if (length) {
997 		int next = laarr[start].extLocation.logicalBlockNum +
998 			(((laarr[start].extLength & UDF_EXTENT_LENGTH_MASK) +
999 			  inode->i_sb->s_blocksize - 1) >>
1000 			  inode->i_sb->s_blocksize_bits);
1001 		int numalloc = udf_prealloc_blocks(inode->i_sb, inode,
1002 				laarr[start].extLocation.partitionReferenceNum,
1003 				next, (UDF_DEFAULT_PREALLOC_BLOCKS > length ?
1004 				length : UDF_DEFAULT_PREALLOC_BLOCKS) -
1005 				currlength);
1006 		if (numalloc) 	{
1007 			if (start == (c + 1))
1008 				laarr[start].extLength +=
1009 					(numalloc <<
1010 					 inode->i_sb->s_blocksize_bits);
1011 			else {
1012 				memmove(&laarr[c + 2], &laarr[c + 1],
1013 					sizeof(struct long_ad) * (*endnum - (c + 1)));
1014 				(*endnum)++;
1015 				laarr[c + 1].extLocation.logicalBlockNum = next;
1016 				laarr[c + 1].extLocation.partitionReferenceNum =
1017 					laarr[c].extLocation.
1018 							partitionReferenceNum;
1019 				laarr[c + 1].extLength =
1020 					EXT_NOT_RECORDED_ALLOCATED |
1021 					(numalloc <<
1022 					 inode->i_sb->s_blocksize_bits);
1023 				start = c + 1;
1024 			}
1025 
1026 			for (i = start + 1; numalloc && i < *endnum; i++) {
1027 				int elen = ((laarr[i].extLength &
1028 						UDF_EXTENT_LENGTH_MASK) +
1029 					    inode->i_sb->s_blocksize - 1) >>
1030 					    inode->i_sb->s_blocksize_bits;
1031 
1032 				if (elen > numalloc) {
1033 					laarr[i].extLength -=
1034 						(numalloc <<
1035 						 inode->i_sb->s_blocksize_bits);
1036 					numalloc = 0;
1037 				} else {
1038 					numalloc -= elen;
1039 					if (*endnum > (i + 1))
1040 						memmove(&laarr[i],
1041 							&laarr[i + 1],
1042 							sizeof(struct long_ad) *
1043 							(*endnum - (i + 1)));
1044 					i--;
1045 					(*endnum)--;
1046 				}
1047 			}
1048 			UDF_I(inode)->i_lenExtents +=
1049 				numalloc << inode->i_sb->s_blocksize_bits;
1050 		}
1051 	}
1052 }
1053 
1054 static void udf_merge_extents(struct inode *inode,
1055 			      struct kernel_long_ad laarr[EXTENT_MERGE_SIZE],
1056 			      int *endnum)
1057 {
1058 	int i;
1059 	unsigned long blocksize = inode->i_sb->s_blocksize;
1060 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1061 
1062 	for (i = 0; i < (*endnum - 1); i++) {
1063 		struct kernel_long_ad *li /*l[i]*/ = &laarr[i];
1064 		struct kernel_long_ad *lip1 /*l[i plus 1]*/ = &laarr[i + 1];
1065 
1066 		if (((li->extLength >> 30) == (lip1->extLength >> 30)) &&
1067 			(((li->extLength >> 30) ==
1068 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) ||
1069 			((lip1->extLocation.logicalBlockNum -
1070 			  li->extLocation.logicalBlockNum) ==
1071 			(((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1072 			blocksize - 1) >> blocksize_bits)))) {
1073 
1074 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1075 				(lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1076 				blocksize - 1) & ~UDF_EXTENT_LENGTH_MASK) {
1077 				lip1->extLength = (lip1->extLength -
1078 						  (li->extLength &
1079 						   UDF_EXTENT_LENGTH_MASK) +
1080 						   UDF_EXTENT_LENGTH_MASK) &
1081 							~(blocksize - 1);
1082 				li->extLength = (li->extLength &
1083 						 UDF_EXTENT_FLAG_MASK) +
1084 						(UDF_EXTENT_LENGTH_MASK + 1) -
1085 						blocksize;
1086 				lip1->extLocation.logicalBlockNum =
1087 					li->extLocation.logicalBlockNum +
1088 					((li->extLength &
1089 						UDF_EXTENT_LENGTH_MASK) >>
1090 						blocksize_bits);
1091 			} else {
1092 				li->extLength = lip1->extLength +
1093 					(((li->extLength &
1094 						UDF_EXTENT_LENGTH_MASK) +
1095 					 blocksize - 1) & ~(blocksize - 1));
1096 				if (*endnum > (i + 2))
1097 					memmove(&laarr[i + 1], &laarr[i + 2],
1098 						sizeof(struct long_ad) *
1099 						(*endnum - (i + 2)));
1100 				i--;
1101 				(*endnum)--;
1102 			}
1103 		} else if (((li->extLength >> 30) ==
1104 				(EXT_NOT_RECORDED_ALLOCATED >> 30)) &&
1105 			   ((lip1->extLength >> 30) ==
1106 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))) {
1107 			udf_free_blocks(inode->i_sb, inode, &li->extLocation, 0,
1108 					((li->extLength &
1109 					  UDF_EXTENT_LENGTH_MASK) +
1110 					 blocksize - 1) >> blocksize_bits);
1111 			li->extLocation.logicalBlockNum = 0;
1112 			li->extLocation.partitionReferenceNum = 0;
1113 
1114 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1115 			     (lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1116 			     blocksize - 1) & ~UDF_EXTENT_LENGTH_MASK) {
1117 				lip1->extLength = (lip1->extLength -
1118 						   (li->extLength &
1119 						   UDF_EXTENT_LENGTH_MASK) +
1120 						   UDF_EXTENT_LENGTH_MASK) &
1121 						   ~(blocksize - 1);
1122 				li->extLength = (li->extLength &
1123 						 UDF_EXTENT_FLAG_MASK) +
1124 						(UDF_EXTENT_LENGTH_MASK + 1) -
1125 						blocksize;
1126 			} else {
1127 				li->extLength = lip1->extLength +
1128 					(((li->extLength &
1129 						UDF_EXTENT_LENGTH_MASK) +
1130 					  blocksize - 1) & ~(blocksize - 1));
1131 				if (*endnum > (i + 2))
1132 					memmove(&laarr[i + 1], &laarr[i + 2],
1133 						sizeof(struct long_ad) *
1134 						(*endnum - (i + 2)));
1135 				i--;
1136 				(*endnum)--;
1137 			}
1138 		} else if ((li->extLength >> 30) ==
1139 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
1140 			udf_free_blocks(inode->i_sb, inode,
1141 					&li->extLocation, 0,
1142 					((li->extLength &
1143 						UDF_EXTENT_LENGTH_MASK) +
1144 					 blocksize - 1) >> blocksize_bits);
1145 			li->extLocation.logicalBlockNum = 0;
1146 			li->extLocation.partitionReferenceNum = 0;
1147 			li->extLength = (li->extLength &
1148 						UDF_EXTENT_LENGTH_MASK) |
1149 						EXT_NOT_RECORDED_NOT_ALLOCATED;
1150 		}
1151 	}
1152 }
1153 
1154 static void udf_update_extents(struct inode *inode,
1155 			       struct kernel_long_ad laarr[EXTENT_MERGE_SIZE],
1156 			       int startnum, int endnum,
1157 			       struct extent_position *epos)
1158 {
1159 	int start = 0, i;
1160 	struct kernel_lb_addr tmploc;
1161 	uint32_t tmplen;
1162 
1163 	if (startnum > endnum) {
1164 		for (i = 0; i < (startnum - endnum); i++)
1165 			udf_delete_aext(inode, *epos, laarr[i].extLocation,
1166 					laarr[i].extLength);
1167 	} else if (startnum < endnum) {
1168 		for (i = 0; i < (endnum - startnum); i++) {
1169 			udf_insert_aext(inode, *epos, laarr[i].extLocation,
1170 					laarr[i].extLength);
1171 			udf_next_aext(inode, epos, &laarr[i].extLocation,
1172 				      &laarr[i].extLength, 1);
1173 			start++;
1174 		}
1175 	}
1176 
1177 	for (i = start; i < endnum; i++) {
1178 		udf_next_aext(inode, epos, &tmploc, &tmplen, 0);
1179 		udf_write_aext(inode, epos, &laarr[i].extLocation,
1180 			       laarr[i].extLength, 1);
1181 	}
1182 }
1183 
1184 struct buffer_head *udf_bread(struct inode *inode, int block,
1185 			      int create, int *err)
1186 {
1187 	struct buffer_head *bh = NULL;
1188 
1189 	bh = udf_getblk(inode, block, create, err);
1190 	if (!bh)
1191 		return NULL;
1192 
1193 	if (buffer_uptodate(bh))
1194 		return bh;
1195 
1196 	ll_rw_block(READ, 1, &bh);
1197 
1198 	wait_on_buffer(bh);
1199 	if (buffer_uptodate(bh))
1200 		return bh;
1201 
1202 	brelse(bh);
1203 	*err = -EIO;
1204 	return NULL;
1205 }
1206 
1207 int udf_setsize(struct inode *inode, loff_t newsize)
1208 {
1209 	int err;
1210 	struct udf_inode_info *iinfo;
1211 	int bsize = 1 << inode->i_blkbits;
1212 
1213 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1214 	      S_ISLNK(inode->i_mode)))
1215 		return -EINVAL;
1216 	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
1217 		return -EPERM;
1218 
1219 	iinfo = UDF_I(inode);
1220 	if (newsize > inode->i_size) {
1221 		down_write(&iinfo->i_data_sem);
1222 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1223 			if (bsize <
1224 			    (udf_file_entry_alloc_offset(inode) + newsize)) {
1225 				err = udf_expand_file_adinicb(inode);
1226 				if (err)
1227 					return err;
1228 				down_write(&iinfo->i_data_sem);
1229 			} else {
1230 				iinfo->i_lenAlloc = newsize;
1231 				goto set_size;
1232 			}
1233 		}
1234 		err = udf_extend_file(inode, newsize);
1235 		if (err) {
1236 			up_write(&iinfo->i_data_sem);
1237 			return err;
1238 		}
1239 set_size:
1240 		truncate_setsize(inode, newsize);
1241 		up_write(&iinfo->i_data_sem);
1242 	} else {
1243 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1244 			down_write(&iinfo->i_data_sem);
1245 			udf_clear_extent_cache(inode);
1246 			memset(iinfo->i_ext.i_data + iinfo->i_lenEAttr + newsize,
1247 			       0x00, bsize - newsize -
1248 			       udf_file_entry_alloc_offset(inode));
1249 			iinfo->i_lenAlloc = newsize;
1250 			truncate_setsize(inode, newsize);
1251 			up_write(&iinfo->i_data_sem);
1252 			goto update_time;
1253 		}
1254 		err = block_truncate_page(inode->i_mapping, newsize,
1255 					  udf_get_block);
1256 		if (err)
1257 			return err;
1258 		down_write(&iinfo->i_data_sem);
1259 		udf_clear_extent_cache(inode);
1260 		truncate_setsize(inode, newsize);
1261 		udf_truncate_extents(inode);
1262 		up_write(&iinfo->i_data_sem);
1263 	}
1264 update_time:
1265 	inode->i_mtime = inode->i_ctime = current_fs_time(inode->i_sb);
1266 	if (IS_SYNC(inode))
1267 		udf_sync_inode(inode);
1268 	else
1269 		mark_inode_dirty(inode);
1270 	return 0;
1271 }
1272 
1273 /*
1274  * Maximum length of linked list formed by ICB hierarchy. The chosen number is
1275  * arbitrary - just that we hopefully don't limit any real use of rewritten
1276  * inode on write-once media but avoid looping for too long on corrupted media.
1277  */
1278 #define UDF_MAX_ICB_NESTING 1024
1279 
1280 static int udf_read_inode(struct inode *inode, bool hidden_inode)
1281 {
1282 	struct buffer_head *bh = NULL;
1283 	struct fileEntry *fe;
1284 	struct extendedFileEntry *efe;
1285 	uint16_t ident;
1286 	struct udf_inode_info *iinfo = UDF_I(inode);
1287 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1288 	struct kernel_lb_addr *iloc = &iinfo->i_location;
1289 	unsigned int link_count;
1290 	unsigned int indirections = 0;
1291 	int bs = inode->i_sb->s_blocksize;
1292 	int ret = -EIO;
1293 
1294 reread:
1295 	if (iloc->logicalBlockNum >=
1296 	    sbi->s_partmaps[iloc->partitionReferenceNum].s_partition_len) {
1297 		udf_debug("block=%d, partition=%d out of range\n",
1298 			  iloc->logicalBlockNum, iloc->partitionReferenceNum);
1299 		return -EIO;
1300 	}
1301 
1302 	/*
1303 	 * Set defaults, but the inode is still incomplete!
1304 	 * Note: get_new_inode() sets the following on a new inode:
1305 	 *      i_sb = sb
1306 	 *      i_no = ino
1307 	 *      i_flags = sb->s_flags
1308 	 *      i_state = 0
1309 	 * clean_inode(): zero fills and sets
1310 	 *      i_count = 1
1311 	 *      i_nlink = 1
1312 	 *      i_op = NULL;
1313 	 */
1314 	bh = udf_read_ptagged(inode->i_sb, iloc, 0, &ident);
1315 	if (!bh) {
1316 		udf_err(inode->i_sb, "(ino %ld) failed !bh\n", inode->i_ino);
1317 		return -EIO;
1318 	}
1319 
1320 	if (ident != TAG_IDENT_FE && ident != TAG_IDENT_EFE &&
1321 	    ident != TAG_IDENT_USE) {
1322 		udf_err(inode->i_sb, "(ino %ld) failed ident=%d\n",
1323 			inode->i_ino, ident);
1324 		goto out;
1325 	}
1326 
1327 	fe = (struct fileEntry *)bh->b_data;
1328 	efe = (struct extendedFileEntry *)bh->b_data;
1329 
1330 	if (fe->icbTag.strategyType == cpu_to_le16(4096)) {
1331 		struct buffer_head *ibh;
1332 
1333 		ibh = udf_read_ptagged(inode->i_sb, iloc, 1, &ident);
1334 		if (ident == TAG_IDENT_IE && ibh) {
1335 			struct kernel_lb_addr loc;
1336 			struct indirectEntry *ie;
1337 
1338 			ie = (struct indirectEntry *)ibh->b_data;
1339 			loc = lelb_to_cpu(ie->indirectICB.extLocation);
1340 
1341 			if (ie->indirectICB.extLength) {
1342 				brelse(ibh);
1343 				memcpy(&iinfo->i_location, &loc,
1344 				       sizeof(struct kernel_lb_addr));
1345 				if (++indirections > UDF_MAX_ICB_NESTING) {
1346 					udf_err(inode->i_sb,
1347 						"too many ICBs in ICB hierarchy"
1348 						" (max %d supported)\n",
1349 						UDF_MAX_ICB_NESTING);
1350 					goto out;
1351 				}
1352 				brelse(bh);
1353 				goto reread;
1354 			}
1355 		}
1356 		brelse(ibh);
1357 	} else if (fe->icbTag.strategyType != cpu_to_le16(4)) {
1358 		udf_err(inode->i_sb, "unsupported strategy type: %d\n",
1359 			le16_to_cpu(fe->icbTag.strategyType));
1360 		goto out;
1361 	}
1362 	if (fe->icbTag.strategyType == cpu_to_le16(4))
1363 		iinfo->i_strat4096 = 0;
1364 	else /* if (fe->icbTag.strategyType == cpu_to_le16(4096)) */
1365 		iinfo->i_strat4096 = 1;
1366 
1367 	iinfo->i_alloc_type = le16_to_cpu(fe->icbTag.flags) &
1368 							ICBTAG_FLAG_AD_MASK;
1369 	iinfo->i_unique = 0;
1370 	iinfo->i_lenEAttr = 0;
1371 	iinfo->i_lenExtents = 0;
1372 	iinfo->i_lenAlloc = 0;
1373 	iinfo->i_next_alloc_block = 0;
1374 	iinfo->i_next_alloc_goal = 0;
1375 	if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_EFE)) {
1376 		iinfo->i_efe = 1;
1377 		iinfo->i_use = 0;
1378 		ret = udf_alloc_i_data(inode, bs -
1379 					sizeof(struct extendedFileEntry));
1380 		if (ret)
1381 			goto out;
1382 		memcpy(iinfo->i_ext.i_data,
1383 		       bh->b_data + sizeof(struct extendedFileEntry),
1384 		       bs - sizeof(struct extendedFileEntry));
1385 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_FE)) {
1386 		iinfo->i_efe = 0;
1387 		iinfo->i_use = 0;
1388 		ret = udf_alloc_i_data(inode, bs - sizeof(struct fileEntry));
1389 		if (ret)
1390 			goto out;
1391 		memcpy(iinfo->i_ext.i_data,
1392 		       bh->b_data + sizeof(struct fileEntry),
1393 		       bs - sizeof(struct fileEntry));
1394 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_USE)) {
1395 		iinfo->i_efe = 0;
1396 		iinfo->i_use = 1;
1397 		iinfo->i_lenAlloc = le32_to_cpu(
1398 				((struct unallocSpaceEntry *)bh->b_data)->
1399 				 lengthAllocDescs);
1400 		ret = udf_alloc_i_data(inode, bs -
1401 					sizeof(struct unallocSpaceEntry));
1402 		if (ret)
1403 			goto out;
1404 		memcpy(iinfo->i_ext.i_data,
1405 		       bh->b_data + sizeof(struct unallocSpaceEntry),
1406 		       bs - sizeof(struct unallocSpaceEntry));
1407 		return 0;
1408 	}
1409 
1410 	ret = -EIO;
1411 	read_lock(&sbi->s_cred_lock);
1412 	i_uid_write(inode, le32_to_cpu(fe->uid));
1413 	if (!uid_valid(inode->i_uid) ||
1414 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_IGNORE) ||
1415 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_SET))
1416 		inode->i_uid = UDF_SB(inode->i_sb)->s_uid;
1417 
1418 	i_gid_write(inode, le32_to_cpu(fe->gid));
1419 	if (!gid_valid(inode->i_gid) ||
1420 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_IGNORE) ||
1421 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_SET))
1422 		inode->i_gid = UDF_SB(inode->i_sb)->s_gid;
1423 
1424 	if (fe->icbTag.fileType != ICBTAG_FILE_TYPE_DIRECTORY &&
1425 			sbi->s_fmode != UDF_INVALID_MODE)
1426 		inode->i_mode = sbi->s_fmode;
1427 	else if (fe->icbTag.fileType == ICBTAG_FILE_TYPE_DIRECTORY &&
1428 			sbi->s_dmode != UDF_INVALID_MODE)
1429 		inode->i_mode = sbi->s_dmode;
1430 	else
1431 		inode->i_mode = udf_convert_permissions(fe);
1432 	inode->i_mode &= ~sbi->s_umask;
1433 	read_unlock(&sbi->s_cred_lock);
1434 
1435 	link_count = le16_to_cpu(fe->fileLinkCount);
1436 	if (!link_count) {
1437 		if (!hidden_inode) {
1438 			ret = -ESTALE;
1439 			goto out;
1440 		}
1441 		link_count = 1;
1442 	}
1443 	set_nlink(inode, link_count);
1444 
1445 	inode->i_size = le64_to_cpu(fe->informationLength);
1446 	iinfo->i_lenExtents = inode->i_size;
1447 
1448 	if (iinfo->i_efe == 0) {
1449 		inode->i_blocks = le64_to_cpu(fe->logicalBlocksRecorded) <<
1450 			(inode->i_sb->s_blocksize_bits - 9);
1451 
1452 		if (!udf_disk_stamp_to_time(&inode->i_atime, fe->accessTime))
1453 			inode->i_atime = sbi->s_record_time;
1454 
1455 		if (!udf_disk_stamp_to_time(&inode->i_mtime,
1456 					    fe->modificationTime))
1457 			inode->i_mtime = sbi->s_record_time;
1458 
1459 		if (!udf_disk_stamp_to_time(&inode->i_ctime, fe->attrTime))
1460 			inode->i_ctime = sbi->s_record_time;
1461 
1462 		iinfo->i_unique = le64_to_cpu(fe->uniqueID);
1463 		iinfo->i_lenEAttr = le32_to_cpu(fe->lengthExtendedAttr);
1464 		iinfo->i_lenAlloc = le32_to_cpu(fe->lengthAllocDescs);
1465 		iinfo->i_checkpoint = le32_to_cpu(fe->checkpoint);
1466 	} else {
1467 		inode->i_blocks = le64_to_cpu(efe->logicalBlocksRecorded) <<
1468 		    (inode->i_sb->s_blocksize_bits - 9);
1469 
1470 		if (!udf_disk_stamp_to_time(&inode->i_atime, efe->accessTime))
1471 			inode->i_atime = sbi->s_record_time;
1472 
1473 		if (!udf_disk_stamp_to_time(&inode->i_mtime,
1474 					    efe->modificationTime))
1475 			inode->i_mtime = sbi->s_record_time;
1476 
1477 		if (!udf_disk_stamp_to_time(&iinfo->i_crtime, efe->createTime))
1478 			iinfo->i_crtime = sbi->s_record_time;
1479 
1480 		if (!udf_disk_stamp_to_time(&inode->i_ctime, efe->attrTime))
1481 			inode->i_ctime = sbi->s_record_time;
1482 
1483 		iinfo->i_unique = le64_to_cpu(efe->uniqueID);
1484 		iinfo->i_lenEAttr = le32_to_cpu(efe->lengthExtendedAttr);
1485 		iinfo->i_lenAlloc = le32_to_cpu(efe->lengthAllocDescs);
1486 		iinfo->i_checkpoint = le32_to_cpu(efe->checkpoint);
1487 	}
1488 	inode->i_generation = iinfo->i_unique;
1489 
1490 	/*
1491 	 * Sanity check length of allocation descriptors and extended attrs to
1492 	 * avoid integer overflows
1493 	 */
1494 	if (iinfo->i_lenEAttr > bs || iinfo->i_lenAlloc > bs)
1495 		goto out;
1496 	/* Now do exact checks */
1497 	if (udf_file_entry_alloc_offset(inode) + iinfo->i_lenAlloc > bs)
1498 		goto out;
1499 	/* Sanity checks for files in ICB so that we don't get confused later */
1500 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1501 		/*
1502 		 * For file in ICB data is stored in allocation descriptor
1503 		 * so sizes should match
1504 		 */
1505 		if (iinfo->i_lenAlloc != inode->i_size)
1506 			goto out;
1507 		/* File in ICB has to fit in there... */
1508 		if (inode->i_size > bs - udf_file_entry_alloc_offset(inode))
1509 			goto out;
1510 	}
1511 
1512 	switch (fe->icbTag.fileType) {
1513 	case ICBTAG_FILE_TYPE_DIRECTORY:
1514 		inode->i_op = &udf_dir_inode_operations;
1515 		inode->i_fop = &udf_dir_operations;
1516 		inode->i_mode |= S_IFDIR;
1517 		inc_nlink(inode);
1518 		break;
1519 	case ICBTAG_FILE_TYPE_REALTIME:
1520 	case ICBTAG_FILE_TYPE_REGULAR:
1521 	case ICBTAG_FILE_TYPE_UNDEF:
1522 	case ICBTAG_FILE_TYPE_VAT20:
1523 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1524 			inode->i_data.a_ops = &udf_adinicb_aops;
1525 		else
1526 			inode->i_data.a_ops = &udf_aops;
1527 		inode->i_op = &udf_file_inode_operations;
1528 		inode->i_fop = &udf_file_operations;
1529 		inode->i_mode |= S_IFREG;
1530 		break;
1531 	case ICBTAG_FILE_TYPE_BLOCK:
1532 		inode->i_mode |= S_IFBLK;
1533 		break;
1534 	case ICBTAG_FILE_TYPE_CHAR:
1535 		inode->i_mode |= S_IFCHR;
1536 		break;
1537 	case ICBTAG_FILE_TYPE_FIFO:
1538 		init_special_inode(inode, inode->i_mode | S_IFIFO, 0);
1539 		break;
1540 	case ICBTAG_FILE_TYPE_SOCKET:
1541 		init_special_inode(inode, inode->i_mode | S_IFSOCK, 0);
1542 		break;
1543 	case ICBTAG_FILE_TYPE_SYMLINK:
1544 		inode->i_data.a_ops = &udf_symlink_aops;
1545 		inode->i_op = &udf_symlink_inode_operations;
1546 		inode->i_mode = S_IFLNK | S_IRWXUGO;
1547 		break;
1548 	case ICBTAG_FILE_TYPE_MAIN:
1549 		udf_debug("METADATA FILE-----\n");
1550 		break;
1551 	case ICBTAG_FILE_TYPE_MIRROR:
1552 		udf_debug("METADATA MIRROR FILE-----\n");
1553 		break;
1554 	case ICBTAG_FILE_TYPE_BITMAP:
1555 		udf_debug("METADATA BITMAP FILE-----\n");
1556 		break;
1557 	default:
1558 		udf_err(inode->i_sb, "(ino %ld) failed unknown file type=%d\n",
1559 			inode->i_ino, fe->icbTag.fileType);
1560 		goto out;
1561 	}
1562 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1563 		struct deviceSpec *dsea =
1564 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1565 		if (dsea) {
1566 			init_special_inode(inode, inode->i_mode,
1567 				MKDEV(le32_to_cpu(dsea->majorDeviceIdent),
1568 				      le32_to_cpu(dsea->minorDeviceIdent)));
1569 			/* Developer ID ??? */
1570 		} else
1571 			goto out;
1572 	}
1573 	ret = 0;
1574 out:
1575 	brelse(bh);
1576 	return ret;
1577 }
1578 
1579 static int udf_alloc_i_data(struct inode *inode, size_t size)
1580 {
1581 	struct udf_inode_info *iinfo = UDF_I(inode);
1582 	iinfo->i_ext.i_data = kmalloc(size, GFP_KERNEL);
1583 
1584 	if (!iinfo->i_ext.i_data) {
1585 		udf_err(inode->i_sb, "(ino %ld) no free memory\n",
1586 			inode->i_ino);
1587 		return -ENOMEM;
1588 	}
1589 
1590 	return 0;
1591 }
1592 
1593 static umode_t udf_convert_permissions(struct fileEntry *fe)
1594 {
1595 	umode_t mode;
1596 	uint32_t permissions;
1597 	uint32_t flags;
1598 
1599 	permissions = le32_to_cpu(fe->permissions);
1600 	flags = le16_to_cpu(fe->icbTag.flags);
1601 
1602 	mode =	((permissions) & S_IRWXO) |
1603 		((permissions >> 2) & S_IRWXG) |
1604 		((permissions >> 4) & S_IRWXU) |
1605 		((flags & ICBTAG_FLAG_SETUID) ? S_ISUID : 0) |
1606 		((flags & ICBTAG_FLAG_SETGID) ? S_ISGID : 0) |
1607 		((flags & ICBTAG_FLAG_STICKY) ? S_ISVTX : 0);
1608 
1609 	return mode;
1610 }
1611 
1612 int udf_write_inode(struct inode *inode, struct writeback_control *wbc)
1613 {
1614 	return udf_update_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
1615 }
1616 
1617 static int udf_sync_inode(struct inode *inode)
1618 {
1619 	return udf_update_inode(inode, 1);
1620 }
1621 
1622 static int udf_update_inode(struct inode *inode, int do_sync)
1623 {
1624 	struct buffer_head *bh = NULL;
1625 	struct fileEntry *fe;
1626 	struct extendedFileEntry *efe;
1627 	uint64_t lb_recorded;
1628 	uint32_t udfperms;
1629 	uint16_t icbflags;
1630 	uint16_t crclen;
1631 	int err = 0;
1632 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1633 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1634 	struct udf_inode_info *iinfo = UDF_I(inode);
1635 
1636 	bh = udf_tgetblk(inode->i_sb,
1637 			udf_get_lb_pblock(inode->i_sb, &iinfo->i_location, 0));
1638 	if (!bh) {
1639 		udf_debug("getblk failure\n");
1640 		return -ENOMEM;
1641 	}
1642 
1643 	lock_buffer(bh);
1644 	memset(bh->b_data, 0, inode->i_sb->s_blocksize);
1645 	fe = (struct fileEntry *)bh->b_data;
1646 	efe = (struct extendedFileEntry *)bh->b_data;
1647 
1648 	if (iinfo->i_use) {
1649 		struct unallocSpaceEntry *use =
1650 			(struct unallocSpaceEntry *)bh->b_data;
1651 
1652 		use->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1653 		memcpy(bh->b_data + sizeof(struct unallocSpaceEntry),
1654 		       iinfo->i_ext.i_data, inode->i_sb->s_blocksize -
1655 					sizeof(struct unallocSpaceEntry));
1656 		use->descTag.tagIdent = cpu_to_le16(TAG_IDENT_USE);
1657 		use->descTag.tagLocation =
1658 				cpu_to_le32(iinfo->i_location.logicalBlockNum);
1659 		crclen = sizeof(struct unallocSpaceEntry) +
1660 				iinfo->i_lenAlloc - sizeof(struct tag);
1661 		use->descTag.descCRCLength = cpu_to_le16(crclen);
1662 		use->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)use +
1663 							   sizeof(struct tag),
1664 							   crclen));
1665 		use->descTag.tagChecksum = udf_tag_checksum(&use->descTag);
1666 
1667 		goto out;
1668 	}
1669 
1670 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_FORGET))
1671 		fe->uid = cpu_to_le32(-1);
1672 	else
1673 		fe->uid = cpu_to_le32(i_uid_read(inode));
1674 
1675 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_FORGET))
1676 		fe->gid = cpu_to_le32(-1);
1677 	else
1678 		fe->gid = cpu_to_le32(i_gid_read(inode));
1679 
1680 	udfperms = ((inode->i_mode & S_IRWXO)) |
1681 		   ((inode->i_mode & S_IRWXG) << 2) |
1682 		   ((inode->i_mode & S_IRWXU) << 4);
1683 
1684 	udfperms |= (le32_to_cpu(fe->permissions) &
1685 		    (FE_PERM_O_DELETE | FE_PERM_O_CHATTR |
1686 		     FE_PERM_G_DELETE | FE_PERM_G_CHATTR |
1687 		     FE_PERM_U_DELETE | FE_PERM_U_CHATTR));
1688 	fe->permissions = cpu_to_le32(udfperms);
1689 
1690 	if (S_ISDIR(inode->i_mode) && inode->i_nlink > 0)
1691 		fe->fileLinkCount = cpu_to_le16(inode->i_nlink - 1);
1692 	else
1693 		fe->fileLinkCount = cpu_to_le16(inode->i_nlink);
1694 
1695 	fe->informationLength = cpu_to_le64(inode->i_size);
1696 
1697 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1698 		struct regid *eid;
1699 		struct deviceSpec *dsea =
1700 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1701 		if (!dsea) {
1702 			dsea = (struct deviceSpec *)
1703 				udf_add_extendedattr(inode,
1704 						     sizeof(struct deviceSpec) +
1705 						     sizeof(struct regid), 12, 0x3);
1706 			dsea->attrType = cpu_to_le32(12);
1707 			dsea->attrSubtype = 1;
1708 			dsea->attrLength = cpu_to_le32(
1709 						sizeof(struct deviceSpec) +
1710 						sizeof(struct regid));
1711 			dsea->impUseLength = cpu_to_le32(sizeof(struct regid));
1712 		}
1713 		eid = (struct regid *)dsea->impUse;
1714 		memset(eid, 0, sizeof(struct regid));
1715 		strcpy(eid->ident, UDF_ID_DEVELOPER);
1716 		eid->identSuffix[0] = UDF_OS_CLASS_UNIX;
1717 		eid->identSuffix[1] = UDF_OS_ID_LINUX;
1718 		dsea->majorDeviceIdent = cpu_to_le32(imajor(inode));
1719 		dsea->minorDeviceIdent = cpu_to_le32(iminor(inode));
1720 	}
1721 
1722 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1723 		lb_recorded = 0; /* No extents => no blocks! */
1724 	else
1725 		lb_recorded =
1726 			(inode->i_blocks + (1 << (blocksize_bits - 9)) - 1) >>
1727 			(blocksize_bits - 9);
1728 
1729 	if (iinfo->i_efe == 0) {
1730 		memcpy(bh->b_data + sizeof(struct fileEntry),
1731 		       iinfo->i_ext.i_data,
1732 		       inode->i_sb->s_blocksize - sizeof(struct fileEntry));
1733 		fe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
1734 
1735 		udf_time_to_disk_stamp(&fe->accessTime, inode->i_atime);
1736 		udf_time_to_disk_stamp(&fe->modificationTime, inode->i_mtime);
1737 		udf_time_to_disk_stamp(&fe->attrTime, inode->i_ctime);
1738 		memset(&(fe->impIdent), 0, sizeof(struct regid));
1739 		strcpy(fe->impIdent.ident, UDF_ID_DEVELOPER);
1740 		fe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1741 		fe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1742 		fe->uniqueID = cpu_to_le64(iinfo->i_unique);
1743 		fe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
1744 		fe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1745 		fe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
1746 		fe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_FE);
1747 		crclen = sizeof(struct fileEntry);
1748 	} else {
1749 		memcpy(bh->b_data + sizeof(struct extendedFileEntry),
1750 		       iinfo->i_ext.i_data,
1751 		       inode->i_sb->s_blocksize -
1752 					sizeof(struct extendedFileEntry));
1753 		efe->objectSize = cpu_to_le64(inode->i_size);
1754 		efe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
1755 
1756 		if (iinfo->i_crtime.tv_sec > inode->i_atime.tv_sec ||
1757 		    (iinfo->i_crtime.tv_sec == inode->i_atime.tv_sec &&
1758 		     iinfo->i_crtime.tv_nsec > inode->i_atime.tv_nsec))
1759 			iinfo->i_crtime = inode->i_atime;
1760 
1761 		if (iinfo->i_crtime.tv_sec > inode->i_mtime.tv_sec ||
1762 		    (iinfo->i_crtime.tv_sec == inode->i_mtime.tv_sec &&
1763 		     iinfo->i_crtime.tv_nsec > inode->i_mtime.tv_nsec))
1764 			iinfo->i_crtime = inode->i_mtime;
1765 
1766 		if (iinfo->i_crtime.tv_sec > inode->i_ctime.tv_sec ||
1767 		    (iinfo->i_crtime.tv_sec == inode->i_ctime.tv_sec &&
1768 		     iinfo->i_crtime.tv_nsec > inode->i_ctime.tv_nsec))
1769 			iinfo->i_crtime = inode->i_ctime;
1770 
1771 		udf_time_to_disk_stamp(&efe->accessTime, inode->i_atime);
1772 		udf_time_to_disk_stamp(&efe->modificationTime, inode->i_mtime);
1773 		udf_time_to_disk_stamp(&efe->createTime, iinfo->i_crtime);
1774 		udf_time_to_disk_stamp(&efe->attrTime, inode->i_ctime);
1775 
1776 		memset(&(efe->impIdent), 0, sizeof(struct regid));
1777 		strcpy(efe->impIdent.ident, UDF_ID_DEVELOPER);
1778 		efe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1779 		efe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1780 		efe->uniqueID = cpu_to_le64(iinfo->i_unique);
1781 		efe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
1782 		efe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1783 		efe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
1784 		efe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EFE);
1785 		crclen = sizeof(struct extendedFileEntry);
1786 	}
1787 	if (iinfo->i_strat4096) {
1788 		fe->icbTag.strategyType = cpu_to_le16(4096);
1789 		fe->icbTag.strategyParameter = cpu_to_le16(1);
1790 		fe->icbTag.numEntries = cpu_to_le16(2);
1791 	} else {
1792 		fe->icbTag.strategyType = cpu_to_le16(4);
1793 		fe->icbTag.numEntries = cpu_to_le16(1);
1794 	}
1795 
1796 	if (S_ISDIR(inode->i_mode))
1797 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_DIRECTORY;
1798 	else if (S_ISREG(inode->i_mode))
1799 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_REGULAR;
1800 	else if (S_ISLNK(inode->i_mode))
1801 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SYMLINK;
1802 	else if (S_ISBLK(inode->i_mode))
1803 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_BLOCK;
1804 	else if (S_ISCHR(inode->i_mode))
1805 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_CHAR;
1806 	else if (S_ISFIFO(inode->i_mode))
1807 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_FIFO;
1808 	else if (S_ISSOCK(inode->i_mode))
1809 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SOCKET;
1810 
1811 	icbflags =	iinfo->i_alloc_type |
1812 			((inode->i_mode & S_ISUID) ? ICBTAG_FLAG_SETUID : 0) |
1813 			((inode->i_mode & S_ISGID) ? ICBTAG_FLAG_SETGID : 0) |
1814 			((inode->i_mode & S_ISVTX) ? ICBTAG_FLAG_STICKY : 0) |
1815 			(le16_to_cpu(fe->icbTag.flags) &
1816 				~(ICBTAG_FLAG_AD_MASK | ICBTAG_FLAG_SETUID |
1817 				ICBTAG_FLAG_SETGID | ICBTAG_FLAG_STICKY));
1818 
1819 	fe->icbTag.flags = cpu_to_le16(icbflags);
1820 	if (sbi->s_udfrev >= 0x0200)
1821 		fe->descTag.descVersion = cpu_to_le16(3);
1822 	else
1823 		fe->descTag.descVersion = cpu_to_le16(2);
1824 	fe->descTag.tagSerialNum = cpu_to_le16(sbi->s_serial_number);
1825 	fe->descTag.tagLocation = cpu_to_le32(
1826 					iinfo->i_location.logicalBlockNum);
1827 	crclen += iinfo->i_lenEAttr + iinfo->i_lenAlloc - sizeof(struct tag);
1828 	fe->descTag.descCRCLength = cpu_to_le16(crclen);
1829 	fe->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)fe + sizeof(struct tag),
1830 						  crclen));
1831 	fe->descTag.tagChecksum = udf_tag_checksum(&fe->descTag);
1832 
1833 out:
1834 	set_buffer_uptodate(bh);
1835 	unlock_buffer(bh);
1836 
1837 	/* write the data blocks */
1838 	mark_buffer_dirty(bh);
1839 	if (do_sync) {
1840 		sync_dirty_buffer(bh);
1841 		if (buffer_write_io_error(bh)) {
1842 			udf_warn(inode->i_sb, "IO error syncing udf inode [%08lx]\n",
1843 				 inode->i_ino);
1844 			err = -EIO;
1845 		}
1846 	}
1847 	brelse(bh);
1848 
1849 	return err;
1850 }
1851 
1852 struct inode *__udf_iget(struct super_block *sb, struct kernel_lb_addr *ino,
1853 			 bool hidden_inode)
1854 {
1855 	unsigned long block = udf_get_lb_pblock(sb, ino, 0);
1856 	struct inode *inode = iget_locked(sb, block);
1857 	int err;
1858 
1859 	if (!inode)
1860 		return ERR_PTR(-ENOMEM);
1861 
1862 	if (!(inode->i_state & I_NEW))
1863 		return inode;
1864 
1865 	memcpy(&UDF_I(inode)->i_location, ino, sizeof(struct kernel_lb_addr));
1866 	err = udf_read_inode(inode, hidden_inode);
1867 	if (err < 0) {
1868 		iget_failed(inode);
1869 		return ERR_PTR(err);
1870 	}
1871 	unlock_new_inode(inode);
1872 
1873 	return inode;
1874 }
1875 
1876 int udf_add_aext(struct inode *inode, struct extent_position *epos,
1877 		 struct kernel_lb_addr *eloc, uint32_t elen, int inc)
1878 {
1879 	int adsize;
1880 	struct short_ad *sad = NULL;
1881 	struct long_ad *lad = NULL;
1882 	struct allocExtDesc *aed;
1883 	uint8_t *ptr;
1884 	struct udf_inode_info *iinfo = UDF_I(inode);
1885 
1886 	if (!epos->bh)
1887 		ptr = iinfo->i_ext.i_data + epos->offset -
1888 			udf_file_entry_alloc_offset(inode) +
1889 			iinfo->i_lenEAttr;
1890 	else
1891 		ptr = epos->bh->b_data + epos->offset;
1892 
1893 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
1894 		adsize = sizeof(struct short_ad);
1895 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
1896 		adsize = sizeof(struct long_ad);
1897 	else
1898 		return -EIO;
1899 
1900 	if (epos->offset + (2 * adsize) > inode->i_sb->s_blocksize) {
1901 		unsigned char *sptr, *dptr;
1902 		struct buffer_head *nbh;
1903 		int err, loffset;
1904 		struct kernel_lb_addr obloc = epos->block;
1905 
1906 		epos->block.logicalBlockNum = udf_new_block(inode->i_sb, NULL,
1907 						obloc.partitionReferenceNum,
1908 						obloc.logicalBlockNum, &err);
1909 		if (!epos->block.logicalBlockNum)
1910 			return -ENOSPC;
1911 		nbh = udf_tgetblk(inode->i_sb, udf_get_lb_pblock(inode->i_sb,
1912 								 &epos->block,
1913 								 0));
1914 		if (!nbh)
1915 			return -EIO;
1916 		lock_buffer(nbh);
1917 		memset(nbh->b_data, 0x00, inode->i_sb->s_blocksize);
1918 		set_buffer_uptodate(nbh);
1919 		unlock_buffer(nbh);
1920 		mark_buffer_dirty_inode(nbh, inode);
1921 
1922 		aed = (struct allocExtDesc *)(nbh->b_data);
1923 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT))
1924 			aed->previousAllocExtLocation =
1925 					cpu_to_le32(obloc.logicalBlockNum);
1926 		if (epos->offset + adsize > inode->i_sb->s_blocksize) {
1927 			loffset = epos->offset;
1928 			aed->lengthAllocDescs = cpu_to_le32(adsize);
1929 			sptr = ptr - adsize;
1930 			dptr = nbh->b_data + sizeof(struct allocExtDesc);
1931 			memcpy(dptr, sptr, adsize);
1932 			epos->offset = sizeof(struct allocExtDesc) + adsize;
1933 		} else {
1934 			loffset = epos->offset + adsize;
1935 			aed->lengthAllocDescs = cpu_to_le32(0);
1936 			sptr = ptr;
1937 			epos->offset = sizeof(struct allocExtDesc);
1938 
1939 			if (epos->bh) {
1940 				aed = (struct allocExtDesc *)epos->bh->b_data;
1941 				le32_add_cpu(&aed->lengthAllocDescs, adsize);
1942 			} else {
1943 				iinfo->i_lenAlloc += adsize;
1944 				mark_inode_dirty(inode);
1945 			}
1946 		}
1947 		if (UDF_SB(inode->i_sb)->s_udfrev >= 0x0200)
1948 			udf_new_tag(nbh->b_data, TAG_IDENT_AED, 3, 1,
1949 				    epos->block.logicalBlockNum, sizeof(struct tag));
1950 		else
1951 			udf_new_tag(nbh->b_data, TAG_IDENT_AED, 2, 1,
1952 				    epos->block.logicalBlockNum, sizeof(struct tag));
1953 		switch (iinfo->i_alloc_type) {
1954 		case ICBTAG_FLAG_AD_SHORT:
1955 			sad = (struct short_ad *)sptr;
1956 			sad->extLength = cpu_to_le32(EXT_NEXT_EXTENT_ALLOCDECS |
1957 						     inode->i_sb->s_blocksize);
1958 			sad->extPosition =
1959 				cpu_to_le32(epos->block.logicalBlockNum);
1960 			break;
1961 		case ICBTAG_FLAG_AD_LONG:
1962 			lad = (struct long_ad *)sptr;
1963 			lad->extLength = cpu_to_le32(EXT_NEXT_EXTENT_ALLOCDECS |
1964 						     inode->i_sb->s_blocksize);
1965 			lad->extLocation = cpu_to_lelb(epos->block);
1966 			memset(lad->impUse, 0x00, sizeof(lad->impUse));
1967 			break;
1968 		}
1969 		if (epos->bh) {
1970 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
1971 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
1972 				udf_update_tag(epos->bh->b_data, loffset);
1973 			else
1974 				udf_update_tag(epos->bh->b_data,
1975 						sizeof(struct allocExtDesc));
1976 			mark_buffer_dirty_inode(epos->bh, inode);
1977 			brelse(epos->bh);
1978 		} else {
1979 			mark_inode_dirty(inode);
1980 		}
1981 		epos->bh = nbh;
1982 	}
1983 
1984 	udf_write_aext(inode, epos, eloc, elen, inc);
1985 
1986 	if (!epos->bh) {
1987 		iinfo->i_lenAlloc += adsize;
1988 		mark_inode_dirty(inode);
1989 	} else {
1990 		aed = (struct allocExtDesc *)epos->bh->b_data;
1991 		le32_add_cpu(&aed->lengthAllocDescs, adsize);
1992 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
1993 				UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
1994 			udf_update_tag(epos->bh->b_data,
1995 					epos->offset + (inc ? 0 : adsize));
1996 		else
1997 			udf_update_tag(epos->bh->b_data,
1998 					sizeof(struct allocExtDesc));
1999 		mark_buffer_dirty_inode(epos->bh, inode);
2000 	}
2001 
2002 	return 0;
2003 }
2004 
2005 void udf_write_aext(struct inode *inode, struct extent_position *epos,
2006 		    struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2007 {
2008 	int adsize;
2009 	uint8_t *ptr;
2010 	struct short_ad *sad;
2011 	struct long_ad *lad;
2012 	struct udf_inode_info *iinfo = UDF_I(inode);
2013 
2014 	if (!epos->bh)
2015 		ptr = iinfo->i_ext.i_data + epos->offset -
2016 			udf_file_entry_alloc_offset(inode) +
2017 			iinfo->i_lenEAttr;
2018 	else
2019 		ptr = epos->bh->b_data + epos->offset;
2020 
2021 	switch (iinfo->i_alloc_type) {
2022 	case ICBTAG_FLAG_AD_SHORT:
2023 		sad = (struct short_ad *)ptr;
2024 		sad->extLength = cpu_to_le32(elen);
2025 		sad->extPosition = cpu_to_le32(eloc->logicalBlockNum);
2026 		adsize = sizeof(struct short_ad);
2027 		break;
2028 	case ICBTAG_FLAG_AD_LONG:
2029 		lad = (struct long_ad *)ptr;
2030 		lad->extLength = cpu_to_le32(elen);
2031 		lad->extLocation = cpu_to_lelb(*eloc);
2032 		memset(lad->impUse, 0x00, sizeof(lad->impUse));
2033 		adsize = sizeof(struct long_ad);
2034 		break;
2035 	default:
2036 		return;
2037 	}
2038 
2039 	if (epos->bh) {
2040 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2041 		    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201) {
2042 			struct allocExtDesc *aed =
2043 				(struct allocExtDesc *)epos->bh->b_data;
2044 			udf_update_tag(epos->bh->b_data,
2045 				       le32_to_cpu(aed->lengthAllocDescs) +
2046 				       sizeof(struct allocExtDesc));
2047 		}
2048 		mark_buffer_dirty_inode(epos->bh, inode);
2049 	} else {
2050 		mark_inode_dirty(inode);
2051 	}
2052 
2053 	if (inc)
2054 		epos->offset += adsize;
2055 }
2056 
2057 int8_t udf_next_aext(struct inode *inode, struct extent_position *epos,
2058 		     struct kernel_lb_addr *eloc, uint32_t *elen, int inc)
2059 {
2060 	int8_t etype;
2061 
2062 	while ((etype = udf_current_aext(inode, epos, eloc, elen, inc)) ==
2063 	       (EXT_NEXT_EXTENT_ALLOCDECS >> 30)) {
2064 		int block;
2065 		epos->block = *eloc;
2066 		epos->offset = sizeof(struct allocExtDesc);
2067 		brelse(epos->bh);
2068 		block = udf_get_lb_pblock(inode->i_sb, &epos->block, 0);
2069 		epos->bh = udf_tread(inode->i_sb, block);
2070 		if (!epos->bh) {
2071 			udf_debug("reading block %d failed!\n", block);
2072 			return -1;
2073 		}
2074 	}
2075 
2076 	return etype;
2077 }
2078 
2079 int8_t udf_current_aext(struct inode *inode, struct extent_position *epos,
2080 			struct kernel_lb_addr *eloc, uint32_t *elen, int inc)
2081 {
2082 	int alen;
2083 	int8_t etype;
2084 	uint8_t *ptr;
2085 	struct short_ad *sad;
2086 	struct long_ad *lad;
2087 	struct udf_inode_info *iinfo = UDF_I(inode);
2088 
2089 	if (!epos->bh) {
2090 		if (!epos->offset)
2091 			epos->offset = udf_file_entry_alloc_offset(inode);
2092 		ptr = iinfo->i_ext.i_data + epos->offset -
2093 			udf_file_entry_alloc_offset(inode) +
2094 			iinfo->i_lenEAttr;
2095 		alen = udf_file_entry_alloc_offset(inode) +
2096 							iinfo->i_lenAlloc;
2097 	} else {
2098 		if (!epos->offset)
2099 			epos->offset = sizeof(struct allocExtDesc);
2100 		ptr = epos->bh->b_data + epos->offset;
2101 		alen = sizeof(struct allocExtDesc) +
2102 			le32_to_cpu(((struct allocExtDesc *)epos->bh->b_data)->
2103 							lengthAllocDescs);
2104 	}
2105 
2106 	switch (iinfo->i_alloc_type) {
2107 	case ICBTAG_FLAG_AD_SHORT:
2108 		sad = udf_get_fileshortad(ptr, alen, &epos->offset, inc);
2109 		if (!sad)
2110 			return -1;
2111 		etype = le32_to_cpu(sad->extLength) >> 30;
2112 		eloc->logicalBlockNum = le32_to_cpu(sad->extPosition);
2113 		eloc->partitionReferenceNum =
2114 				iinfo->i_location.partitionReferenceNum;
2115 		*elen = le32_to_cpu(sad->extLength) & UDF_EXTENT_LENGTH_MASK;
2116 		break;
2117 	case ICBTAG_FLAG_AD_LONG:
2118 		lad = udf_get_filelongad(ptr, alen, &epos->offset, inc);
2119 		if (!lad)
2120 			return -1;
2121 		etype = le32_to_cpu(lad->extLength) >> 30;
2122 		*eloc = lelb_to_cpu(lad->extLocation);
2123 		*elen = le32_to_cpu(lad->extLength) & UDF_EXTENT_LENGTH_MASK;
2124 		break;
2125 	default:
2126 		udf_debug("alloc_type = %d unsupported\n", iinfo->i_alloc_type);
2127 		return -1;
2128 	}
2129 
2130 	return etype;
2131 }
2132 
2133 static int8_t udf_insert_aext(struct inode *inode, struct extent_position epos,
2134 			      struct kernel_lb_addr neloc, uint32_t nelen)
2135 {
2136 	struct kernel_lb_addr oeloc;
2137 	uint32_t oelen;
2138 	int8_t etype;
2139 
2140 	if (epos.bh)
2141 		get_bh(epos.bh);
2142 
2143 	while ((etype = udf_next_aext(inode, &epos, &oeloc, &oelen, 0)) != -1) {
2144 		udf_write_aext(inode, &epos, &neloc, nelen, 1);
2145 		neloc = oeloc;
2146 		nelen = (etype << 30) | oelen;
2147 	}
2148 	udf_add_aext(inode, &epos, &neloc, nelen, 1);
2149 	brelse(epos.bh);
2150 
2151 	return (nelen >> 30);
2152 }
2153 
2154 int8_t udf_delete_aext(struct inode *inode, struct extent_position epos,
2155 		       struct kernel_lb_addr eloc, uint32_t elen)
2156 {
2157 	struct extent_position oepos;
2158 	int adsize;
2159 	int8_t etype;
2160 	struct allocExtDesc *aed;
2161 	struct udf_inode_info *iinfo;
2162 
2163 	if (epos.bh) {
2164 		get_bh(epos.bh);
2165 		get_bh(epos.bh);
2166 	}
2167 
2168 	iinfo = UDF_I(inode);
2169 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2170 		adsize = sizeof(struct short_ad);
2171 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2172 		adsize = sizeof(struct long_ad);
2173 	else
2174 		adsize = 0;
2175 
2176 	oepos = epos;
2177 	if (udf_next_aext(inode, &epos, &eloc, &elen, 1) == -1)
2178 		return -1;
2179 
2180 	while ((etype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1) {
2181 		udf_write_aext(inode, &oepos, &eloc, (etype << 30) | elen, 1);
2182 		if (oepos.bh != epos.bh) {
2183 			oepos.block = epos.block;
2184 			brelse(oepos.bh);
2185 			get_bh(epos.bh);
2186 			oepos.bh = epos.bh;
2187 			oepos.offset = epos.offset - adsize;
2188 		}
2189 	}
2190 	memset(&eloc, 0x00, sizeof(struct kernel_lb_addr));
2191 	elen = 0;
2192 
2193 	if (epos.bh != oepos.bh) {
2194 		udf_free_blocks(inode->i_sb, inode, &epos.block, 0, 1);
2195 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2196 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2197 		if (!oepos.bh) {
2198 			iinfo->i_lenAlloc -= (adsize * 2);
2199 			mark_inode_dirty(inode);
2200 		} else {
2201 			aed = (struct allocExtDesc *)oepos.bh->b_data;
2202 			le32_add_cpu(&aed->lengthAllocDescs, -(2 * adsize));
2203 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2204 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2205 				udf_update_tag(oepos.bh->b_data,
2206 						oepos.offset - (2 * adsize));
2207 			else
2208 				udf_update_tag(oepos.bh->b_data,
2209 						sizeof(struct allocExtDesc));
2210 			mark_buffer_dirty_inode(oepos.bh, inode);
2211 		}
2212 	} else {
2213 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2214 		if (!oepos.bh) {
2215 			iinfo->i_lenAlloc -= adsize;
2216 			mark_inode_dirty(inode);
2217 		} else {
2218 			aed = (struct allocExtDesc *)oepos.bh->b_data;
2219 			le32_add_cpu(&aed->lengthAllocDescs, -adsize);
2220 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2221 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2222 				udf_update_tag(oepos.bh->b_data,
2223 						epos.offset - adsize);
2224 			else
2225 				udf_update_tag(oepos.bh->b_data,
2226 						sizeof(struct allocExtDesc));
2227 			mark_buffer_dirty_inode(oepos.bh, inode);
2228 		}
2229 	}
2230 
2231 	brelse(epos.bh);
2232 	brelse(oepos.bh);
2233 
2234 	return (elen >> 30);
2235 }
2236 
2237 int8_t inode_bmap(struct inode *inode, sector_t block,
2238 		  struct extent_position *pos, struct kernel_lb_addr *eloc,
2239 		  uint32_t *elen, sector_t *offset)
2240 {
2241 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
2242 	loff_t lbcount = 0, bcount =
2243 	    (loff_t) block << blocksize_bits;
2244 	int8_t etype;
2245 	struct udf_inode_info *iinfo;
2246 
2247 	iinfo = UDF_I(inode);
2248 	if (!udf_read_extent_cache(inode, bcount, &lbcount, pos)) {
2249 		pos->offset = 0;
2250 		pos->block = iinfo->i_location;
2251 		pos->bh = NULL;
2252 	}
2253 	*elen = 0;
2254 	do {
2255 		etype = udf_next_aext(inode, pos, eloc, elen, 1);
2256 		if (etype == -1) {
2257 			*offset = (bcount - lbcount) >> blocksize_bits;
2258 			iinfo->i_lenExtents = lbcount;
2259 			return -1;
2260 		}
2261 		lbcount += *elen;
2262 	} while (lbcount <= bcount);
2263 	/* update extent cache */
2264 	udf_update_extent_cache(inode, lbcount - *elen, pos, 1);
2265 	*offset = (bcount + *elen - lbcount) >> blocksize_bits;
2266 
2267 	return etype;
2268 }
2269 
2270 long udf_block_map(struct inode *inode, sector_t block)
2271 {
2272 	struct kernel_lb_addr eloc;
2273 	uint32_t elen;
2274 	sector_t offset;
2275 	struct extent_position epos = {};
2276 	int ret;
2277 
2278 	down_read(&UDF_I(inode)->i_data_sem);
2279 
2280 	if (inode_bmap(inode, block, &epos, &eloc, &elen, &offset) ==
2281 						(EXT_RECORDED_ALLOCATED >> 30))
2282 		ret = udf_get_lb_pblock(inode->i_sb, &eloc, offset);
2283 	else
2284 		ret = 0;
2285 
2286 	up_read(&UDF_I(inode)->i_data_sem);
2287 	brelse(epos.bh);
2288 
2289 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_VARCONV))
2290 		return udf_fixed_to_variable(ret);
2291 	else
2292 		return ret;
2293 }
2294