xref: /openbmc/linux/fs/udf/inode.c (revision a06c488d)
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(!inode_is_locked(inode));
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 		struct kernel_lb_addr tmploc;
544 		uint32_t tmplen;
545 
546 		udf_write_aext(inode, last_pos, &last_ext->extLocation,
547 				last_ext->extLength, 1);
548 		/*
549 		 * We've rewritten the last extent but there may be empty
550 		 * indirect extent after it - enter it.
551 		 */
552 		udf_next_aext(inode, last_pos, &tmploc, &tmplen, 0);
553 	}
554 
555 	/* Managed to do everything necessary? */
556 	if (!blocks)
557 		goto out;
558 
559 	/* All further extents will be NOT_RECORDED_NOT_ALLOCATED */
560 	last_ext->extLocation.logicalBlockNum = 0;
561 	last_ext->extLocation.partitionReferenceNum = 0;
562 	add = (1 << (30-sb->s_blocksize_bits)) - 1;
563 	last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
564 				(add << sb->s_blocksize_bits);
565 
566 	/* Create enough extents to cover the whole hole */
567 	while (blocks > add) {
568 		blocks -= add;
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 	if (blocks) {
576 		last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
577 			(blocks << sb->s_blocksize_bits);
578 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
579 				   last_ext->extLength, 1);
580 		if (err)
581 			return err;
582 		count++;
583 	}
584 
585 out:
586 	/* Do we have some preallocated blocks saved? */
587 	if (prealloc_len) {
588 		err = udf_add_aext(inode, last_pos, &prealloc_loc,
589 				   prealloc_len, 1);
590 		if (err)
591 			return err;
592 		last_ext->extLocation = prealloc_loc;
593 		last_ext->extLength = prealloc_len;
594 		count++;
595 	}
596 
597 	/* last_pos should point to the last written extent... */
598 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
599 		last_pos->offset -= sizeof(struct short_ad);
600 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
601 		last_pos->offset -= sizeof(struct long_ad);
602 	else
603 		return -EIO;
604 
605 	return count;
606 }
607 
608 static int udf_extend_file(struct inode *inode, loff_t newsize)
609 {
610 
611 	struct extent_position epos;
612 	struct kernel_lb_addr eloc;
613 	uint32_t elen;
614 	int8_t etype;
615 	struct super_block *sb = inode->i_sb;
616 	sector_t first_block = newsize >> sb->s_blocksize_bits, offset;
617 	int adsize;
618 	struct udf_inode_info *iinfo = UDF_I(inode);
619 	struct kernel_long_ad extent;
620 	int err;
621 
622 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
623 		adsize = sizeof(struct short_ad);
624 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
625 		adsize = sizeof(struct long_ad);
626 	else
627 		BUG();
628 
629 	etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset);
630 
631 	/* File has extent covering the new size (could happen when extending
632 	 * inside a block)? */
633 	if (etype != -1)
634 		return 0;
635 	if (newsize & (sb->s_blocksize - 1))
636 		offset++;
637 	/* Extended file just to the boundary of the last file block? */
638 	if (offset == 0)
639 		return 0;
640 
641 	/* Truncate is extending the file by 'offset' blocks */
642 	if ((!epos.bh && epos.offset == udf_file_entry_alloc_offset(inode)) ||
643 	    (epos.bh && epos.offset == sizeof(struct allocExtDesc))) {
644 		/* File has no extents at all or has empty last
645 		 * indirect extent! Create a fake extent... */
646 		extent.extLocation.logicalBlockNum = 0;
647 		extent.extLocation.partitionReferenceNum = 0;
648 		extent.extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
649 	} else {
650 		epos.offset -= adsize;
651 		etype = udf_next_aext(inode, &epos, &extent.extLocation,
652 				      &extent.extLength, 0);
653 		extent.extLength |= etype << 30;
654 	}
655 	err = udf_do_extend_file(inode, &epos, &extent, offset);
656 	if (err < 0)
657 		goto out;
658 	err = 0;
659 	iinfo->i_lenExtents = newsize;
660 out:
661 	brelse(epos.bh);
662 	return err;
663 }
664 
665 static sector_t inode_getblk(struct inode *inode, sector_t block,
666 			     int *err, int *new)
667 {
668 	struct kernel_long_ad laarr[EXTENT_MERGE_SIZE];
669 	struct extent_position prev_epos, cur_epos, next_epos;
670 	int count = 0, startnum = 0, endnum = 0;
671 	uint32_t elen = 0, tmpelen;
672 	struct kernel_lb_addr eloc, tmpeloc;
673 	int c = 1;
674 	loff_t lbcount = 0, b_off = 0;
675 	uint32_t newblocknum, newblock;
676 	sector_t offset = 0;
677 	int8_t etype;
678 	struct udf_inode_info *iinfo = UDF_I(inode);
679 	int goal = 0, pgoal = iinfo->i_location.logicalBlockNum;
680 	int lastblock = 0;
681 	bool isBeyondEOF;
682 
683 	*err = 0;
684 	*new = 0;
685 	prev_epos.offset = udf_file_entry_alloc_offset(inode);
686 	prev_epos.block = iinfo->i_location;
687 	prev_epos.bh = NULL;
688 	cur_epos = next_epos = prev_epos;
689 	b_off = (loff_t)block << inode->i_sb->s_blocksize_bits;
690 
691 	/* find the extent which contains the block we are looking for.
692 	   alternate between laarr[0] and laarr[1] for locations of the
693 	   current extent, and the previous extent */
694 	do {
695 		if (prev_epos.bh != cur_epos.bh) {
696 			brelse(prev_epos.bh);
697 			get_bh(cur_epos.bh);
698 			prev_epos.bh = cur_epos.bh;
699 		}
700 		if (cur_epos.bh != next_epos.bh) {
701 			brelse(cur_epos.bh);
702 			get_bh(next_epos.bh);
703 			cur_epos.bh = next_epos.bh;
704 		}
705 
706 		lbcount += elen;
707 
708 		prev_epos.block = cur_epos.block;
709 		cur_epos.block = next_epos.block;
710 
711 		prev_epos.offset = cur_epos.offset;
712 		cur_epos.offset = next_epos.offset;
713 
714 		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 1);
715 		if (etype == -1)
716 			break;
717 
718 		c = !c;
719 
720 		laarr[c].extLength = (etype << 30) | elen;
721 		laarr[c].extLocation = eloc;
722 
723 		if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
724 			pgoal = eloc.logicalBlockNum +
725 				((elen + inode->i_sb->s_blocksize - 1) >>
726 				 inode->i_sb->s_blocksize_bits);
727 
728 		count++;
729 	} while (lbcount + elen <= b_off);
730 
731 	b_off -= lbcount;
732 	offset = b_off >> inode->i_sb->s_blocksize_bits;
733 	/*
734 	 * Move prev_epos and cur_epos into indirect extent if we are at
735 	 * the pointer to it
736 	 */
737 	udf_next_aext(inode, &prev_epos, &tmpeloc, &tmpelen, 0);
738 	udf_next_aext(inode, &cur_epos, &tmpeloc, &tmpelen, 0);
739 
740 	/* if the extent is allocated and recorded, return the block
741 	   if the extent is not a multiple of the blocksize, round up */
742 
743 	if (etype == (EXT_RECORDED_ALLOCATED >> 30)) {
744 		if (elen & (inode->i_sb->s_blocksize - 1)) {
745 			elen = EXT_RECORDED_ALLOCATED |
746 				((elen + inode->i_sb->s_blocksize - 1) &
747 				 ~(inode->i_sb->s_blocksize - 1));
748 			udf_write_aext(inode, &cur_epos, &eloc, elen, 1);
749 		}
750 		brelse(prev_epos.bh);
751 		brelse(cur_epos.bh);
752 		brelse(next_epos.bh);
753 		newblock = udf_get_lb_pblock(inode->i_sb, &eloc, offset);
754 		return newblock;
755 	}
756 
757 	/* Are we beyond EOF? */
758 	if (etype == -1) {
759 		int ret;
760 		isBeyondEOF = true;
761 		if (count) {
762 			if (c)
763 				laarr[0] = laarr[1];
764 			startnum = 1;
765 		} else {
766 			/* Create a fake extent when there's not one */
767 			memset(&laarr[0].extLocation, 0x00,
768 				sizeof(struct kernel_lb_addr));
769 			laarr[0].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
770 			/* Will udf_do_extend_file() create real extent from
771 			   a fake one? */
772 			startnum = (offset > 0);
773 		}
774 		/* Create extents for the hole between EOF and offset */
775 		ret = udf_do_extend_file(inode, &prev_epos, laarr, offset);
776 		if (ret < 0) {
777 			brelse(prev_epos.bh);
778 			brelse(cur_epos.bh);
779 			brelse(next_epos.bh);
780 			*err = ret;
781 			return 0;
782 		}
783 		c = 0;
784 		offset = 0;
785 		count += ret;
786 		/* We are not covered by a preallocated extent? */
787 		if ((laarr[0].extLength & UDF_EXTENT_FLAG_MASK) !=
788 						EXT_NOT_RECORDED_ALLOCATED) {
789 			/* Is there any real extent? - otherwise we overwrite
790 			 * the fake one... */
791 			if (count)
792 				c = !c;
793 			laarr[c].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
794 				inode->i_sb->s_blocksize;
795 			memset(&laarr[c].extLocation, 0x00,
796 				sizeof(struct kernel_lb_addr));
797 			count++;
798 		}
799 		endnum = c + 1;
800 		lastblock = 1;
801 	} else {
802 		isBeyondEOF = false;
803 		endnum = startnum = ((count > 2) ? 2 : count);
804 
805 		/* if the current extent is in position 0,
806 		   swap it with the previous */
807 		if (!c && count != 1) {
808 			laarr[2] = laarr[0];
809 			laarr[0] = laarr[1];
810 			laarr[1] = laarr[2];
811 			c = 1;
812 		}
813 
814 		/* if the current block is located in an extent,
815 		   read the next extent */
816 		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 0);
817 		if (etype != -1) {
818 			laarr[c + 1].extLength = (etype << 30) | elen;
819 			laarr[c + 1].extLocation = eloc;
820 			count++;
821 			startnum++;
822 			endnum++;
823 		} else
824 			lastblock = 1;
825 	}
826 
827 	/* if the current extent is not recorded but allocated, get the
828 	 * block in the extent corresponding to the requested block */
829 	if ((laarr[c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30))
830 		newblocknum = laarr[c].extLocation.logicalBlockNum + offset;
831 	else { /* otherwise, allocate a new block */
832 		if (iinfo->i_next_alloc_block == block)
833 			goal = iinfo->i_next_alloc_goal;
834 
835 		if (!goal) {
836 			if (!(goal = pgoal)) /* XXX: what was intended here? */
837 				goal = iinfo->i_location.logicalBlockNum + 1;
838 		}
839 
840 		newblocknum = udf_new_block(inode->i_sb, inode,
841 				iinfo->i_location.partitionReferenceNum,
842 				goal, err);
843 		if (!newblocknum) {
844 			brelse(prev_epos.bh);
845 			brelse(cur_epos.bh);
846 			brelse(next_epos.bh);
847 			*err = -ENOSPC;
848 			return 0;
849 		}
850 		if (isBeyondEOF)
851 			iinfo->i_lenExtents += inode->i_sb->s_blocksize;
852 	}
853 
854 	/* if the extent the requsted block is located in contains multiple
855 	 * blocks, split the extent into at most three extents. blocks prior
856 	 * to requested block, requested block, and blocks after requested
857 	 * block */
858 	udf_split_extents(inode, &c, offset, newblocknum, laarr, &endnum);
859 
860 #ifdef UDF_PREALLOCATE
861 	/* We preallocate blocks only for regular files. It also makes sense
862 	 * for directories but there's a problem when to drop the
863 	 * preallocation. We might use some delayed work for that but I feel
864 	 * it's overengineering for a filesystem like UDF. */
865 	if (S_ISREG(inode->i_mode))
866 		udf_prealloc_extents(inode, c, lastblock, laarr, &endnum);
867 #endif
868 
869 	/* merge any continuous blocks in laarr */
870 	udf_merge_extents(inode, laarr, &endnum);
871 
872 	/* write back the new extents, inserting new extents if the new number
873 	 * of extents is greater than the old number, and deleting extents if
874 	 * the new number of extents is less than the old number */
875 	udf_update_extents(inode, laarr, startnum, endnum, &prev_epos);
876 
877 	brelse(prev_epos.bh);
878 	brelse(cur_epos.bh);
879 	brelse(next_epos.bh);
880 
881 	newblock = udf_get_pblock(inode->i_sb, newblocknum,
882 				iinfo->i_location.partitionReferenceNum, 0);
883 	if (!newblock) {
884 		*err = -EIO;
885 		return 0;
886 	}
887 	*new = 1;
888 	iinfo->i_next_alloc_block = block;
889 	iinfo->i_next_alloc_goal = newblocknum;
890 	inode->i_ctime = current_fs_time(inode->i_sb);
891 
892 	if (IS_SYNC(inode))
893 		udf_sync_inode(inode);
894 	else
895 		mark_inode_dirty(inode);
896 
897 	return newblock;
898 }
899 
900 static void udf_split_extents(struct inode *inode, int *c, int offset,
901 			      int newblocknum,
902 			      struct kernel_long_ad laarr[EXTENT_MERGE_SIZE],
903 			      int *endnum)
904 {
905 	unsigned long blocksize = inode->i_sb->s_blocksize;
906 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
907 
908 	if ((laarr[*c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30) ||
909 	    (laarr[*c].extLength >> 30) ==
910 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
911 		int curr = *c;
912 		int blen = ((laarr[curr].extLength & UDF_EXTENT_LENGTH_MASK) +
913 			    blocksize - 1) >> blocksize_bits;
914 		int8_t etype = (laarr[curr].extLength >> 30);
915 
916 		if (blen == 1)
917 			;
918 		else if (!offset || blen == offset + 1) {
919 			laarr[curr + 2] = laarr[curr + 1];
920 			laarr[curr + 1] = laarr[curr];
921 		} else {
922 			laarr[curr + 3] = laarr[curr + 1];
923 			laarr[curr + 2] = laarr[curr + 1] = laarr[curr];
924 		}
925 
926 		if (offset) {
927 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
928 				udf_free_blocks(inode->i_sb, inode,
929 						&laarr[curr].extLocation,
930 						0, offset);
931 				laarr[curr].extLength =
932 					EXT_NOT_RECORDED_NOT_ALLOCATED |
933 					(offset << blocksize_bits);
934 				laarr[curr].extLocation.logicalBlockNum = 0;
935 				laarr[curr].extLocation.
936 						partitionReferenceNum = 0;
937 			} else
938 				laarr[curr].extLength = (etype << 30) |
939 					(offset << blocksize_bits);
940 			curr++;
941 			(*c)++;
942 			(*endnum)++;
943 		}
944 
945 		laarr[curr].extLocation.logicalBlockNum = newblocknum;
946 		if (etype == (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
947 			laarr[curr].extLocation.partitionReferenceNum =
948 				UDF_I(inode)->i_location.partitionReferenceNum;
949 		laarr[curr].extLength = EXT_RECORDED_ALLOCATED |
950 			blocksize;
951 		curr++;
952 
953 		if (blen != offset + 1) {
954 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
955 				laarr[curr].extLocation.logicalBlockNum +=
956 								offset + 1;
957 			laarr[curr].extLength = (etype << 30) |
958 				((blen - (offset + 1)) << blocksize_bits);
959 			curr++;
960 			(*endnum)++;
961 		}
962 	}
963 }
964 
965 static void udf_prealloc_extents(struct inode *inode, int c, int lastblock,
966 				 struct kernel_long_ad laarr[EXTENT_MERGE_SIZE],
967 				 int *endnum)
968 {
969 	int start, length = 0, currlength = 0, i;
970 
971 	if (*endnum >= (c + 1)) {
972 		if (!lastblock)
973 			return;
974 		else
975 			start = c;
976 	} else {
977 		if ((laarr[c + 1].extLength >> 30) ==
978 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
979 			start = c + 1;
980 			length = currlength =
981 				(((laarr[c + 1].extLength &
982 					UDF_EXTENT_LENGTH_MASK) +
983 				inode->i_sb->s_blocksize - 1) >>
984 				inode->i_sb->s_blocksize_bits);
985 		} else
986 			start = c;
987 	}
988 
989 	for (i = start + 1; i <= *endnum; i++) {
990 		if (i == *endnum) {
991 			if (lastblock)
992 				length += UDF_DEFAULT_PREALLOC_BLOCKS;
993 		} else if ((laarr[i].extLength >> 30) ==
994 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
995 			length += (((laarr[i].extLength &
996 						UDF_EXTENT_LENGTH_MASK) +
997 				    inode->i_sb->s_blocksize - 1) >>
998 				    inode->i_sb->s_blocksize_bits);
999 		} else
1000 			break;
1001 	}
1002 
1003 	if (length) {
1004 		int next = laarr[start].extLocation.logicalBlockNum +
1005 			(((laarr[start].extLength & UDF_EXTENT_LENGTH_MASK) +
1006 			  inode->i_sb->s_blocksize - 1) >>
1007 			  inode->i_sb->s_blocksize_bits);
1008 		int numalloc = udf_prealloc_blocks(inode->i_sb, inode,
1009 				laarr[start].extLocation.partitionReferenceNum,
1010 				next, (UDF_DEFAULT_PREALLOC_BLOCKS > length ?
1011 				length : UDF_DEFAULT_PREALLOC_BLOCKS) -
1012 				currlength);
1013 		if (numalloc) 	{
1014 			if (start == (c + 1))
1015 				laarr[start].extLength +=
1016 					(numalloc <<
1017 					 inode->i_sb->s_blocksize_bits);
1018 			else {
1019 				memmove(&laarr[c + 2], &laarr[c + 1],
1020 					sizeof(struct long_ad) * (*endnum - (c + 1)));
1021 				(*endnum)++;
1022 				laarr[c + 1].extLocation.logicalBlockNum = next;
1023 				laarr[c + 1].extLocation.partitionReferenceNum =
1024 					laarr[c].extLocation.
1025 							partitionReferenceNum;
1026 				laarr[c + 1].extLength =
1027 					EXT_NOT_RECORDED_ALLOCATED |
1028 					(numalloc <<
1029 					 inode->i_sb->s_blocksize_bits);
1030 				start = c + 1;
1031 			}
1032 
1033 			for (i = start + 1; numalloc && i < *endnum; i++) {
1034 				int elen = ((laarr[i].extLength &
1035 						UDF_EXTENT_LENGTH_MASK) +
1036 					    inode->i_sb->s_blocksize - 1) >>
1037 					    inode->i_sb->s_blocksize_bits;
1038 
1039 				if (elen > numalloc) {
1040 					laarr[i].extLength -=
1041 						(numalloc <<
1042 						 inode->i_sb->s_blocksize_bits);
1043 					numalloc = 0;
1044 				} else {
1045 					numalloc -= elen;
1046 					if (*endnum > (i + 1))
1047 						memmove(&laarr[i],
1048 							&laarr[i + 1],
1049 							sizeof(struct long_ad) *
1050 							(*endnum - (i + 1)));
1051 					i--;
1052 					(*endnum)--;
1053 				}
1054 			}
1055 			UDF_I(inode)->i_lenExtents +=
1056 				numalloc << inode->i_sb->s_blocksize_bits;
1057 		}
1058 	}
1059 }
1060 
1061 static void udf_merge_extents(struct inode *inode,
1062 			      struct kernel_long_ad laarr[EXTENT_MERGE_SIZE],
1063 			      int *endnum)
1064 {
1065 	int i;
1066 	unsigned long blocksize = inode->i_sb->s_blocksize;
1067 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1068 
1069 	for (i = 0; i < (*endnum - 1); i++) {
1070 		struct kernel_long_ad *li /*l[i]*/ = &laarr[i];
1071 		struct kernel_long_ad *lip1 /*l[i plus 1]*/ = &laarr[i + 1];
1072 
1073 		if (((li->extLength >> 30) == (lip1->extLength >> 30)) &&
1074 			(((li->extLength >> 30) ==
1075 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) ||
1076 			((lip1->extLocation.logicalBlockNum -
1077 			  li->extLocation.logicalBlockNum) ==
1078 			(((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1079 			blocksize - 1) >> blocksize_bits)))) {
1080 
1081 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1082 				(lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1083 				blocksize - 1) & ~UDF_EXTENT_LENGTH_MASK) {
1084 				lip1->extLength = (lip1->extLength -
1085 						  (li->extLength &
1086 						   UDF_EXTENT_LENGTH_MASK) +
1087 						   UDF_EXTENT_LENGTH_MASK) &
1088 							~(blocksize - 1);
1089 				li->extLength = (li->extLength &
1090 						 UDF_EXTENT_FLAG_MASK) +
1091 						(UDF_EXTENT_LENGTH_MASK + 1) -
1092 						blocksize;
1093 				lip1->extLocation.logicalBlockNum =
1094 					li->extLocation.logicalBlockNum +
1095 					((li->extLength &
1096 						UDF_EXTENT_LENGTH_MASK) >>
1097 						blocksize_bits);
1098 			} else {
1099 				li->extLength = lip1->extLength +
1100 					(((li->extLength &
1101 						UDF_EXTENT_LENGTH_MASK) +
1102 					 blocksize - 1) & ~(blocksize - 1));
1103 				if (*endnum > (i + 2))
1104 					memmove(&laarr[i + 1], &laarr[i + 2],
1105 						sizeof(struct long_ad) *
1106 						(*endnum - (i + 2)));
1107 				i--;
1108 				(*endnum)--;
1109 			}
1110 		} else if (((li->extLength >> 30) ==
1111 				(EXT_NOT_RECORDED_ALLOCATED >> 30)) &&
1112 			   ((lip1->extLength >> 30) ==
1113 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))) {
1114 			udf_free_blocks(inode->i_sb, inode, &li->extLocation, 0,
1115 					((li->extLength &
1116 					  UDF_EXTENT_LENGTH_MASK) +
1117 					 blocksize - 1) >> blocksize_bits);
1118 			li->extLocation.logicalBlockNum = 0;
1119 			li->extLocation.partitionReferenceNum = 0;
1120 
1121 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1122 			     (lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1123 			     blocksize - 1) & ~UDF_EXTENT_LENGTH_MASK) {
1124 				lip1->extLength = (lip1->extLength -
1125 						   (li->extLength &
1126 						   UDF_EXTENT_LENGTH_MASK) +
1127 						   UDF_EXTENT_LENGTH_MASK) &
1128 						   ~(blocksize - 1);
1129 				li->extLength = (li->extLength &
1130 						 UDF_EXTENT_FLAG_MASK) +
1131 						(UDF_EXTENT_LENGTH_MASK + 1) -
1132 						blocksize;
1133 			} else {
1134 				li->extLength = lip1->extLength +
1135 					(((li->extLength &
1136 						UDF_EXTENT_LENGTH_MASK) +
1137 					  blocksize - 1) & ~(blocksize - 1));
1138 				if (*endnum > (i + 2))
1139 					memmove(&laarr[i + 1], &laarr[i + 2],
1140 						sizeof(struct long_ad) *
1141 						(*endnum - (i + 2)));
1142 				i--;
1143 				(*endnum)--;
1144 			}
1145 		} else if ((li->extLength >> 30) ==
1146 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
1147 			udf_free_blocks(inode->i_sb, inode,
1148 					&li->extLocation, 0,
1149 					((li->extLength &
1150 						UDF_EXTENT_LENGTH_MASK) +
1151 					 blocksize - 1) >> blocksize_bits);
1152 			li->extLocation.logicalBlockNum = 0;
1153 			li->extLocation.partitionReferenceNum = 0;
1154 			li->extLength = (li->extLength &
1155 						UDF_EXTENT_LENGTH_MASK) |
1156 						EXT_NOT_RECORDED_NOT_ALLOCATED;
1157 		}
1158 	}
1159 }
1160 
1161 static void udf_update_extents(struct inode *inode,
1162 			       struct kernel_long_ad laarr[EXTENT_MERGE_SIZE],
1163 			       int startnum, int endnum,
1164 			       struct extent_position *epos)
1165 {
1166 	int start = 0, i;
1167 	struct kernel_lb_addr tmploc;
1168 	uint32_t tmplen;
1169 
1170 	if (startnum > endnum) {
1171 		for (i = 0; i < (startnum - endnum); i++)
1172 			udf_delete_aext(inode, *epos, laarr[i].extLocation,
1173 					laarr[i].extLength);
1174 	} else if (startnum < endnum) {
1175 		for (i = 0; i < (endnum - startnum); i++) {
1176 			udf_insert_aext(inode, *epos, laarr[i].extLocation,
1177 					laarr[i].extLength);
1178 			udf_next_aext(inode, epos, &laarr[i].extLocation,
1179 				      &laarr[i].extLength, 1);
1180 			start++;
1181 		}
1182 	}
1183 
1184 	for (i = start; i < endnum; i++) {
1185 		udf_next_aext(inode, epos, &tmploc, &tmplen, 0);
1186 		udf_write_aext(inode, epos, &laarr[i].extLocation,
1187 			       laarr[i].extLength, 1);
1188 	}
1189 }
1190 
1191 struct buffer_head *udf_bread(struct inode *inode, int block,
1192 			      int create, int *err)
1193 {
1194 	struct buffer_head *bh = NULL;
1195 
1196 	bh = udf_getblk(inode, block, create, err);
1197 	if (!bh)
1198 		return NULL;
1199 
1200 	if (buffer_uptodate(bh))
1201 		return bh;
1202 
1203 	ll_rw_block(READ, 1, &bh);
1204 
1205 	wait_on_buffer(bh);
1206 	if (buffer_uptodate(bh))
1207 		return bh;
1208 
1209 	brelse(bh);
1210 	*err = -EIO;
1211 	return NULL;
1212 }
1213 
1214 int udf_setsize(struct inode *inode, loff_t newsize)
1215 {
1216 	int err;
1217 	struct udf_inode_info *iinfo;
1218 	int bsize = 1 << inode->i_blkbits;
1219 
1220 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1221 	      S_ISLNK(inode->i_mode)))
1222 		return -EINVAL;
1223 	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
1224 		return -EPERM;
1225 
1226 	iinfo = UDF_I(inode);
1227 	if (newsize > inode->i_size) {
1228 		down_write(&iinfo->i_data_sem);
1229 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1230 			if (bsize <
1231 			    (udf_file_entry_alloc_offset(inode) + newsize)) {
1232 				err = udf_expand_file_adinicb(inode);
1233 				if (err)
1234 					return err;
1235 				down_write(&iinfo->i_data_sem);
1236 			} else {
1237 				iinfo->i_lenAlloc = newsize;
1238 				goto set_size;
1239 			}
1240 		}
1241 		err = udf_extend_file(inode, newsize);
1242 		if (err) {
1243 			up_write(&iinfo->i_data_sem);
1244 			return err;
1245 		}
1246 set_size:
1247 		truncate_setsize(inode, newsize);
1248 		up_write(&iinfo->i_data_sem);
1249 	} else {
1250 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1251 			down_write(&iinfo->i_data_sem);
1252 			udf_clear_extent_cache(inode);
1253 			memset(iinfo->i_ext.i_data + iinfo->i_lenEAttr + newsize,
1254 			       0x00, bsize - newsize -
1255 			       udf_file_entry_alloc_offset(inode));
1256 			iinfo->i_lenAlloc = newsize;
1257 			truncate_setsize(inode, newsize);
1258 			up_write(&iinfo->i_data_sem);
1259 			goto update_time;
1260 		}
1261 		err = block_truncate_page(inode->i_mapping, newsize,
1262 					  udf_get_block);
1263 		if (err)
1264 			return err;
1265 		down_write(&iinfo->i_data_sem);
1266 		udf_clear_extent_cache(inode);
1267 		truncate_setsize(inode, newsize);
1268 		udf_truncate_extents(inode);
1269 		up_write(&iinfo->i_data_sem);
1270 	}
1271 update_time:
1272 	inode->i_mtime = inode->i_ctime = current_fs_time(inode->i_sb);
1273 	if (IS_SYNC(inode))
1274 		udf_sync_inode(inode);
1275 	else
1276 		mark_inode_dirty(inode);
1277 	return 0;
1278 }
1279 
1280 /*
1281  * Maximum length of linked list formed by ICB hierarchy. The chosen number is
1282  * arbitrary - just that we hopefully don't limit any real use of rewritten
1283  * inode on write-once media but avoid looping for too long on corrupted media.
1284  */
1285 #define UDF_MAX_ICB_NESTING 1024
1286 
1287 static int udf_read_inode(struct inode *inode, bool hidden_inode)
1288 {
1289 	struct buffer_head *bh = NULL;
1290 	struct fileEntry *fe;
1291 	struct extendedFileEntry *efe;
1292 	uint16_t ident;
1293 	struct udf_inode_info *iinfo = UDF_I(inode);
1294 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1295 	struct kernel_lb_addr *iloc = &iinfo->i_location;
1296 	unsigned int link_count;
1297 	unsigned int indirections = 0;
1298 	int bs = inode->i_sb->s_blocksize;
1299 	int ret = -EIO;
1300 
1301 reread:
1302 	if (iloc->logicalBlockNum >=
1303 	    sbi->s_partmaps[iloc->partitionReferenceNum].s_partition_len) {
1304 		udf_debug("block=%d, partition=%d out of range\n",
1305 			  iloc->logicalBlockNum, iloc->partitionReferenceNum);
1306 		return -EIO;
1307 	}
1308 
1309 	/*
1310 	 * Set defaults, but the inode is still incomplete!
1311 	 * Note: get_new_inode() sets the following on a new inode:
1312 	 *      i_sb = sb
1313 	 *      i_no = ino
1314 	 *      i_flags = sb->s_flags
1315 	 *      i_state = 0
1316 	 * clean_inode(): zero fills and sets
1317 	 *      i_count = 1
1318 	 *      i_nlink = 1
1319 	 *      i_op = NULL;
1320 	 */
1321 	bh = udf_read_ptagged(inode->i_sb, iloc, 0, &ident);
1322 	if (!bh) {
1323 		udf_err(inode->i_sb, "(ino %ld) failed !bh\n", inode->i_ino);
1324 		return -EIO;
1325 	}
1326 
1327 	if (ident != TAG_IDENT_FE && ident != TAG_IDENT_EFE &&
1328 	    ident != TAG_IDENT_USE) {
1329 		udf_err(inode->i_sb, "(ino %ld) failed ident=%d\n",
1330 			inode->i_ino, ident);
1331 		goto out;
1332 	}
1333 
1334 	fe = (struct fileEntry *)bh->b_data;
1335 	efe = (struct extendedFileEntry *)bh->b_data;
1336 
1337 	if (fe->icbTag.strategyType == cpu_to_le16(4096)) {
1338 		struct buffer_head *ibh;
1339 
1340 		ibh = udf_read_ptagged(inode->i_sb, iloc, 1, &ident);
1341 		if (ident == TAG_IDENT_IE && ibh) {
1342 			struct kernel_lb_addr loc;
1343 			struct indirectEntry *ie;
1344 
1345 			ie = (struct indirectEntry *)ibh->b_data;
1346 			loc = lelb_to_cpu(ie->indirectICB.extLocation);
1347 
1348 			if (ie->indirectICB.extLength) {
1349 				brelse(ibh);
1350 				memcpy(&iinfo->i_location, &loc,
1351 				       sizeof(struct kernel_lb_addr));
1352 				if (++indirections > UDF_MAX_ICB_NESTING) {
1353 					udf_err(inode->i_sb,
1354 						"too many ICBs in ICB hierarchy"
1355 						" (max %d supported)\n",
1356 						UDF_MAX_ICB_NESTING);
1357 					goto out;
1358 				}
1359 				brelse(bh);
1360 				goto reread;
1361 			}
1362 		}
1363 		brelse(ibh);
1364 	} else if (fe->icbTag.strategyType != cpu_to_le16(4)) {
1365 		udf_err(inode->i_sb, "unsupported strategy type: %d\n",
1366 			le16_to_cpu(fe->icbTag.strategyType));
1367 		goto out;
1368 	}
1369 	if (fe->icbTag.strategyType == cpu_to_le16(4))
1370 		iinfo->i_strat4096 = 0;
1371 	else /* if (fe->icbTag.strategyType == cpu_to_le16(4096)) */
1372 		iinfo->i_strat4096 = 1;
1373 
1374 	iinfo->i_alloc_type = le16_to_cpu(fe->icbTag.flags) &
1375 							ICBTAG_FLAG_AD_MASK;
1376 	iinfo->i_unique = 0;
1377 	iinfo->i_lenEAttr = 0;
1378 	iinfo->i_lenExtents = 0;
1379 	iinfo->i_lenAlloc = 0;
1380 	iinfo->i_next_alloc_block = 0;
1381 	iinfo->i_next_alloc_goal = 0;
1382 	if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_EFE)) {
1383 		iinfo->i_efe = 1;
1384 		iinfo->i_use = 0;
1385 		ret = udf_alloc_i_data(inode, bs -
1386 					sizeof(struct extendedFileEntry));
1387 		if (ret)
1388 			goto out;
1389 		memcpy(iinfo->i_ext.i_data,
1390 		       bh->b_data + sizeof(struct extendedFileEntry),
1391 		       bs - sizeof(struct extendedFileEntry));
1392 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_FE)) {
1393 		iinfo->i_efe = 0;
1394 		iinfo->i_use = 0;
1395 		ret = udf_alloc_i_data(inode, bs - sizeof(struct fileEntry));
1396 		if (ret)
1397 			goto out;
1398 		memcpy(iinfo->i_ext.i_data,
1399 		       bh->b_data + sizeof(struct fileEntry),
1400 		       bs - sizeof(struct fileEntry));
1401 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_USE)) {
1402 		iinfo->i_efe = 0;
1403 		iinfo->i_use = 1;
1404 		iinfo->i_lenAlloc = le32_to_cpu(
1405 				((struct unallocSpaceEntry *)bh->b_data)->
1406 				 lengthAllocDescs);
1407 		ret = udf_alloc_i_data(inode, bs -
1408 					sizeof(struct unallocSpaceEntry));
1409 		if (ret)
1410 			goto out;
1411 		memcpy(iinfo->i_ext.i_data,
1412 		       bh->b_data + sizeof(struct unallocSpaceEntry),
1413 		       bs - sizeof(struct unallocSpaceEntry));
1414 		return 0;
1415 	}
1416 
1417 	ret = -EIO;
1418 	read_lock(&sbi->s_cred_lock);
1419 	i_uid_write(inode, le32_to_cpu(fe->uid));
1420 	if (!uid_valid(inode->i_uid) ||
1421 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_IGNORE) ||
1422 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_SET))
1423 		inode->i_uid = UDF_SB(inode->i_sb)->s_uid;
1424 
1425 	i_gid_write(inode, le32_to_cpu(fe->gid));
1426 	if (!gid_valid(inode->i_gid) ||
1427 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_IGNORE) ||
1428 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_SET))
1429 		inode->i_gid = UDF_SB(inode->i_sb)->s_gid;
1430 
1431 	if (fe->icbTag.fileType != ICBTAG_FILE_TYPE_DIRECTORY &&
1432 			sbi->s_fmode != UDF_INVALID_MODE)
1433 		inode->i_mode = sbi->s_fmode;
1434 	else if (fe->icbTag.fileType == ICBTAG_FILE_TYPE_DIRECTORY &&
1435 			sbi->s_dmode != UDF_INVALID_MODE)
1436 		inode->i_mode = sbi->s_dmode;
1437 	else
1438 		inode->i_mode = udf_convert_permissions(fe);
1439 	inode->i_mode &= ~sbi->s_umask;
1440 	read_unlock(&sbi->s_cred_lock);
1441 
1442 	link_count = le16_to_cpu(fe->fileLinkCount);
1443 	if (!link_count) {
1444 		if (!hidden_inode) {
1445 			ret = -ESTALE;
1446 			goto out;
1447 		}
1448 		link_count = 1;
1449 	}
1450 	set_nlink(inode, link_count);
1451 
1452 	inode->i_size = le64_to_cpu(fe->informationLength);
1453 	iinfo->i_lenExtents = inode->i_size;
1454 
1455 	if (iinfo->i_efe == 0) {
1456 		inode->i_blocks = le64_to_cpu(fe->logicalBlocksRecorded) <<
1457 			(inode->i_sb->s_blocksize_bits - 9);
1458 
1459 		if (!udf_disk_stamp_to_time(&inode->i_atime, fe->accessTime))
1460 			inode->i_atime = sbi->s_record_time;
1461 
1462 		if (!udf_disk_stamp_to_time(&inode->i_mtime,
1463 					    fe->modificationTime))
1464 			inode->i_mtime = sbi->s_record_time;
1465 
1466 		if (!udf_disk_stamp_to_time(&inode->i_ctime, fe->attrTime))
1467 			inode->i_ctime = sbi->s_record_time;
1468 
1469 		iinfo->i_unique = le64_to_cpu(fe->uniqueID);
1470 		iinfo->i_lenEAttr = le32_to_cpu(fe->lengthExtendedAttr);
1471 		iinfo->i_lenAlloc = le32_to_cpu(fe->lengthAllocDescs);
1472 		iinfo->i_checkpoint = le32_to_cpu(fe->checkpoint);
1473 	} else {
1474 		inode->i_blocks = le64_to_cpu(efe->logicalBlocksRecorded) <<
1475 		    (inode->i_sb->s_blocksize_bits - 9);
1476 
1477 		if (!udf_disk_stamp_to_time(&inode->i_atime, efe->accessTime))
1478 			inode->i_atime = sbi->s_record_time;
1479 
1480 		if (!udf_disk_stamp_to_time(&inode->i_mtime,
1481 					    efe->modificationTime))
1482 			inode->i_mtime = sbi->s_record_time;
1483 
1484 		if (!udf_disk_stamp_to_time(&iinfo->i_crtime, efe->createTime))
1485 			iinfo->i_crtime = sbi->s_record_time;
1486 
1487 		if (!udf_disk_stamp_to_time(&inode->i_ctime, efe->attrTime))
1488 			inode->i_ctime = sbi->s_record_time;
1489 
1490 		iinfo->i_unique = le64_to_cpu(efe->uniqueID);
1491 		iinfo->i_lenEAttr = le32_to_cpu(efe->lengthExtendedAttr);
1492 		iinfo->i_lenAlloc = le32_to_cpu(efe->lengthAllocDescs);
1493 		iinfo->i_checkpoint = le32_to_cpu(efe->checkpoint);
1494 	}
1495 	inode->i_generation = iinfo->i_unique;
1496 
1497 	/*
1498 	 * Sanity check length of allocation descriptors and extended attrs to
1499 	 * avoid integer overflows
1500 	 */
1501 	if (iinfo->i_lenEAttr > bs || iinfo->i_lenAlloc > bs)
1502 		goto out;
1503 	/* Now do exact checks */
1504 	if (udf_file_entry_alloc_offset(inode) + iinfo->i_lenAlloc > bs)
1505 		goto out;
1506 	/* Sanity checks for files in ICB so that we don't get confused later */
1507 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1508 		/*
1509 		 * For file in ICB data is stored in allocation descriptor
1510 		 * so sizes should match
1511 		 */
1512 		if (iinfo->i_lenAlloc != inode->i_size)
1513 			goto out;
1514 		/* File in ICB has to fit in there... */
1515 		if (inode->i_size > bs - udf_file_entry_alloc_offset(inode))
1516 			goto out;
1517 	}
1518 
1519 	switch (fe->icbTag.fileType) {
1520 	case ICBTAG_FILE_TYPE_DIRECTORY:
1521 		inode->i_op = &udf_dir_inode_operations;
1522 		inode->i_fop = &udf_dir_operations;
1523 		inode->i_mode |= S_IFDIR;
1524 		inc_nlink(inode);
1525 		break;
1526 	case ICBTAG_FILE_TYPE_REALTIME:
1527 	case ICBTAG_FILE_TYPE_REGULAR:
1528 	case ICBTAG_FILE_TYPE_UNDEF:
1529 	case ICBTAG_FILE_TYPE_VAT20:
1530 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1531 			inode->i_data.a_ops = &udf_adinicb_aops;
1532 		else
1533 			inode->i_data.a_ops = &udf_aops;
1534 		inode->i_op = &udf_file_inode_operations;
1535 		inode->i_fop = &udf_file_operations;
1536 		inode->i_mode |= S_IFREG;
1537 		break;
1538 	case ICBTAG_FILE_TYPE_BLOCK:
1539 		inode->i_mode |= S_IFBLK;
1540 		break;
1541 	case ICBTAG_FILE_TYPE_CHAR:
1542 		inode->i_mode |= S_IFCHR;
1543 		break;
1544 	case ICBTAG_FILE_TYPE_FIFO:
1545 		init_special_inode(inode, inode->i_mode | S_IFIFO, 0);
1546 		break;
1547 	case ICBTAG_FILE_TYPE_SOCKET:
1548 		init_special_inode(inode, inode->i_mode | S_IFSOCK, 0);
1549 		break;
1550 	case ICBTAG_FILE_TYPE_SYMLINK:
1551 		inode->i_data.a_ops = &udf_symlink_aops;
1552 		inode->i_op = &page_symlink_inode_operations;
1553 		inode_nohighmem(inode);
1554 		inode->i_mode = S_IFLNK | S_IRWXUGO;
1555 		break;
1556 	case ICBTAG_FILE_TYPE_MAIN:
1557 		udf_debug("METADATA FILE-----\n");
1558 		break;
1559 	case ICBTAG_FILE_TYPE_MIRROR:
1560 		udf_debug("METADATA MIRROR FILE-----\n");
1561 		break;
1562 	case ICBTAG_FILE_TYPE_BITMAP:
1563 		udf_debug("METADATA BITMAP FILE-----\n");
1564 		break;
1565 	default:
1566 		udf_err(inode->i_sb, "(ino %ld) failed unknown file type=%d\n",
1567 			inode->i_ino, fe->icbTag.fileType);
1568 		goto out;
1569 	}
1570 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1571 		struct deviceSpec *dsea =
1572 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1573 		if (dsea) {
1574 			init_special_inode(inode, inode->i_mode,
1575 				MKDEV(le32_to_cpu(dsea->majorDeviceIdent),
1576 				      le32_to_cpu(dsea->minorDeviceIdent)));
1577 			/* Developer ID ??? */
1578 		} else
1579 			goto out;
1580 	}
1581 	ret = 0;
1582 out:
1583 	brelse(bh);
1584 	return ret;
1585 }
1586 
1587 static int udf_alloc_i_data(struct inode *inode, size_t size)
1588 {
1589 	struct udf_inode_info *iinfo = UDF_I(inode);
1590 	iinfo->i_ext.i_data = kmalloc(size, GFP_KERNEL);
1591 
1592 	if (!iinfo->i_ext.i_data) {
1593 		udf_err(inode->i_sb, "(ino %ld) no free memory\n",
1594 			inode->i_ino);
1595 		return -ENOMEM;
1596 	}
1597 
1598 	return 0;
1599 }
1600 
1601 static umode_t udf_convert_permissions(struct fileEntry *fe)
1602 {
1603 	umode_t mode;
1604 	uint32_t permissions;
1605 	uint32_t flags;
1606 
1607 	permissions = le32_to_cpu(fe->permissions);
1608 	flags = le16_to_cpu(fe->icbTag.flags);
1609 
1610 	mode =	((permissions) & S_IRWXO) |
1611 		((permissions >> 2) & S_IRWXG) |
1612 		((permissions >> 4) & S_IRWXU) |
1613 		((flags & ICBTAG_FLAG_SETUID) ? S_ISUID : 0) |
1614 		((flags & ICBTAG_FLAG_SETGID) ? S_ISGID : 0) |
1615 		((flags & ICBTAG_FLAG_STICKY) ? S_ISVTX : 0);
1616 
1617 	return mode;
1618 }
1619 
1620 int udf_write_inode(struct inode *inode, struct writeback_control *wbc)
1621 {
1622 	return udf_update_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
1623 }
1624 
1625 static int udf_sync_inode(struct inode *inode)
1626 {
1627 	return udf_update_inode(inode, 1);
1628 }
1629 
1630 static int udf_update_inode(struct inode *inode, int do_sync)
1631 {
1632 	struct buffer_head *bh = NULL;
1633 	struct fileEntry *fe;
1634 	struct extendedFileEntry *efe;
1635 	uint64_t lb_recorded;
1636 	uint32_t udfperms;
1637 	uint16_t icbflags;
1638 	uint16_t crclen;
1639 	int err = 0;
1640 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1641 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1642 	struct udf_inode_info *iinfo = UDF_I(inode);
1643 
1644 	bh = udf_tgetblk(inode->i_sb,
1645 			udf_get_lb_pblock(inode->i_sb, &iinfo->i_location, 0));
1646 	if (!bh) {
1647 		udf_debug("getblk failure\n");
1648 		return -EIO;
1649 	}
1650 
1651 	lock_buffer(bh);
1652 	memset(bh->b_data, 0, inode->i_sb->s_blocksize);
1653 	fe = (struct fileEntry *)bh->b_data;
1654 	efe = (struct extendedFileEntry *)bh->b_data;
1655 
1656 	if (iinfo->i_use) {
1657 		struct unallocSpaceEntry *use =
1658 			(struct unallocSpaceEntry *)bh->b_data;
1659 
1660 		use->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1661 		memcpy(bh->b_data + sizeof(struct unallocSpaceEntry),
1662 		       iinfo->i_ext.i_data, inode->i_sb->s_blocksize -
1663 					sizeof(struct unallocSpaceEntry));
1664 		use->descTag.tagIdent = cpu_to_le16(TAG_IDENT_USE);
1665 		crclen = sizeof(struct unallocSpaceEntry);
1666 
1667 		goto finish;
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 
1788 finish:
1789 	if (iinfo->i_strat4096) {
1790 		fe->icbTag.strategyType = cpu_to_le16(4096);
1791 		fe->icbTag.strategyParameter = cpu_to_le16(1);
1792 		fe->icbTag.numEntries = cpu_to_le16(2);
1793 	} else {
1794 		fe->icbTag.strategyType = cpu_to_le16(4);
1795 		fe->icbTag.numEntries = cpu_to_le16(1);
1796 	}
1797 
1798 	if (iinfo->i_use)
1799 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_USE;
1800 	else if (S_ISDIR(inode->i_mode))
1801 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_DIRECTORY;
1802 	else if (S_ISREG(inode->i_mode))
1803 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_REGULAR;
1804 	else if (S_ISLNK(inode->i_mode))
1805 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SYMLINK;
1806 	else if (S_ISBLK(inode->i_mode))
1807 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_BLOCK;
1808 	else if (S_ISCHR(inode->i_mode))
1809 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_CHAR;
1810 	else if (S_ISFIFO(inode->i_mode))
1811 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_FIFO;
1812 	else if (S_ISSOCK(inode->i_mode))
1813 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SOCKET;
1814 
1815 	icbflags =	iinfo->i_alloc_type |
1816 			((inode->i_mode & S_ISUID) ? ICBTAG_FLAG_SETUID : 0) |
1817 			((inode->i_mode & S_ISGID) ? ICBTAG_FLAG_SETGID : 0) |
1818 			((inode->i_mode & S_ISVTX) ? ICBTAG_FLAG_STICKY : 0) |
1819 			(le16_to_cpu(fe->icbTag.flags) &
1820 				~(ICBTAG_FLAG_AD_MASK | ICBTAG_FLAG_SETUID |
1821 				ICBTAG_FLAG_SETGID | ICBTAG_FLAG_STICKY));
1822 
1823 	fe->icbTag.flags = cpu_to_le16(icbflags);
1824 	if (sbi->s_udfrev >= 0x0200)
1825 		fe->descTag.descVersion = cpu_to_le16(3);
1826 	else
1827 		fe->descTag.descVersion = cpu_to_le16(2);
1828 	fe->descTag.tagSerialNum = cpu_to_le16(sbi->s_serial_number);
1829 	fe->descTag.tagLocation = cpu_to_le32(
1830 					iinfo->i_location.logicalBlockNum);
1831 	crclen += iinfo->i_lenEAttr + iinfo->i_lenAlloc - sizeof(struct tag);
1832 	fe->descTag.descCRCLength = cpu_to_le16(crclen);
1833 	fe->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)fe + sizeof(struct tag),
1834 						  crclen));
1835 	fe->descTag.tagChecksum = udf_tag_checksum(&fe->descTag);
1836 
1837 	set_buffer_uptodate(bh);
1838 	unlock_buffer(bh);
1839 
1840 	/* write the data blocks */
1841 	mark_buffer_dirty(bh);
1842 	if (do_sync) {
1843 		sync_dirty_buffer(bh);
1844 		if (buffer_write_io_error(bh)) {
1845 			udf_warn(inode->i_sb, "IO error syncing udf inode [%08lx]\n",
1846 				 inode->i_ino);
1847 			err = -EIO;
1848 		}
1849 	}
1850 	brelse(bh);
1851 
1852 	return err;
1853 }
1854 
1855 struct inode *__udf_iget(struct super_block *sb, struct kernel_lb_addr *ino,
1856 			 bool hidden_inode)
1857 {
1858 	unsigned long block = udf_get_lb_pblock(sb, ino, 0);
1859 	struct inode *inode = iget_locked(sb, block);
1860 	int err;
1861 
1862 	if (!inode)
1863 		return ERR_PTR(-ENOMEM);
1864 
1865 	if (!(inode->i_state & I_NEW))
1866 		return inode;
1867 
1868 	memcpy(&UDF_I(inode)->i_location, ino, sizeof(struct kernel_lb_addr));
1869 	err = udf_read_inode(inode, hidden_inode);
1870 	if (err < 0) {
1871 		iget_failed(inode);
1872 		return ERR_PTR(err);
1873 	}
1874 	unlock_new_inode(inode);
1875 
1876 	return inode;
1877 }
1878 
1879 int udf_setup_indirect_aext(struct inode *inode, int block,
1880 			    struct extent_position *epos)
1881 {
1882 	struct super_block *sb = inode->i_sb;
1883 	struct buffer_head *bh;
1884 	struct allocExtDesc *aed;
1885 	struct extent_position nepos;
1886 	struct kernel_lb_addr neloc;
1887 	int ver, adsize;
1888 
1889 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
1890 		adsize = sizeof(struct short_ad);
1891 	else if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_LONG)
1892 		adsize = sizeof(struct long_ad);
1893 	else
1894 		return -EIO;
1895 
1896 	neloc.logicalBlockNum = block;
1897 	neloc.partitionReferenceNum = epos->block.partitionReferenceNum;
1898 
1899 	bh = udf_tgetblk(sb, udf_get_lb_pblock(sb, &neloc, 0));
1900 	if (!bh)
1901 		return -EIO;
1902 	lock_buffer(bh);
1903 	memset(bh->b_data, 0x00, sb->s_blocksize);
1904 	set_buffer_uptodate(bh);
1905 	unlock_buffer(bh);
1906 	mark_buffer_dirty_inode(bh, inode);
1907 
1908 	aed = (struct allocExtDesc *)(bh->b_data);
1909 	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT)) {
1910 		aed->previousAllocExtLocation =
1911 				cpu_to_le32(epos->block.logicalBlockNum);
1912 	}
1913 	aed->lengthAllocDescs = cpu_to_le32(0);
1914 	if (UDF_SB(sb)->s_udfrev >= 0x0200)
1915 		ver = 3;
1916 	else
1917 		ver = 2;
1918 	udf_new_tag(bh->b_data, TAG_IDENT_AED, ver, 1, block,
1919 		    sizeof(struct tag));
1920 
1921 	nepos.block = neloc;
1922 	nepos.offset = sizeof(struct allocExtDesc);
1923 	nepos.bh = bh;
1924 
1925 	/*
1926 	 * Do we have to copy current last extent to make space for indirect
1927 	 * one?
1928 	 */
1929 	if (epos->offset + adsize > sb->s_blocksize) {
1930 		struct kernel_lb_addr cp_loc;
1931 		uint32_t cp_len;
1932 		int cp_type;
1933 
1934 		epos->offset -= adsize;
1935 		cp_type = udf_current_aext(inode, epos, &cp_loc, &cp_len, 0);
1936 		cp_len |= ((uint32_t)cp_type) << 30;
1937 
1938 		__udf_add_aext(inode, &nepos, &cp_loc, cp_len, 1);
1939 		udf_write_aext(inode, epos, &nepos.block,
1940 			       sb->s_blocksize | EXT_NEXT_EXTENT_ALLOCDECS, 0);
1941 	} else {
1942 		__udf_add_aext(inode, epos, &nepos.block,
1943 			       sb->s_blocksize | EXT_NEXT_EXTENT_ALLOCDECS, 0);
1944 	}
1945 
1946 	brelse(epos->bh);
1947 	*epos = nepos;
1948 
1949 	return 0;
1950 }
1951 
1952 /*
1953  * Append extent at the given position - should be the first free one in inode
1954  * / indirect extent. This function assumes there is enough space in the inode
1955  * or indirect extent. Use udf_add_aext() if you didn't check for this before.
1956  */
1957 int __udf_add_aext(struct inode *inode, struct extent_position *epos,
1958 		   struct kernel_lb_addr *eloc, uint32_t elen, int inc)
1959 {
1960 	struct udf_inode_info *iinfo = UDF_I(inode);
1961 	struct allocExtDesc *aed;
1962 	int adsize;
1963 
1964 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
1965 		adsize = sizeof(struct short_ad);
1966 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
1967 		adsize = sizeof(struct long_ad);
1968 	else
1969 		return -EIO;
1970 
1971 	if (!epos->bh) {
1972 		WARN_ON(iinfo->i_lenAlloc !=
1973 			epos->offset - udf_file_entry_alloc_offset(inode));
1974 	} else {
1975 		aed = (struct allocExtDesc *)epos->bh->b_data;
1976 		WARN_ON(le32_to_cpu(aed->lengthAllocDescs) !=
1977 			epos->offset - sizeof(struct allocExtDesc));
1978 		WARN_ON(epos->offset + adsize > inode->i_sb->s_blocksize);
1979 	}
1980 
1981 	udf_write_aext(inode, epos, eloc, elen, inc);
1982 
1983 	if (!epos->bh) {
1984 		iinfo->i_lenAlloc += adsize;
1985 		mark_inode_dirty(inode);
1986 	} else {
1987 		aed = (struct allocExtDesc *)epos->bh->b_data;
1988 		le32_add_cpu(&aed->lengthAllocDescs, adsize);
1989 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
1990 				UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
1991 			udf_update_tag(epos->bh->b_data,
1992 					epos->offset + (inc ? 0 : adsize));
1993 		else
1994 			udf_update_tag(epos->bh->b_data,
1995 					sizeof(struct allocExtDesc));
1996 		mark_buffer_dirty_inode(epos->bh, inode);
1997 	}
1998 
1999 	return 0;
2000 }
2001 
2002 /*
2003  * Append extent at given position - should be the first free one in inode
2004  * / indirect extent. Takes care of allocating and linking indirect blocks.
2005  */
2006 int udf_add_aext(struct inode *inode, struct extent_position *epos,
2007 		 struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2008 {
2009 	int adsize;
2010 	struct super_block *sb = inode->i_sb;
2011 
2012 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2013 		adsize = sizeof(struct short_ad);
2014 	else if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2015 		adsize = sizeof(struct long_ad);
2016 	else
2017 		return -EIO;
2018 
2019 	if (epos->offset + (2 * adsize) > sb->s_blocksize) {
2020 		int err;
2021 		int new_block;
2022 
2023 		new_block = udf_new_block(sb, NULL,
2024 					  epos->block.partitionReferenceNum,
2025 					  epos->block.logicalBlockNum, &err);
2026 		if (!new_block)
2027 			return -ENOSPC;
2028 
2029 		err = udf_setup_indirect_aext(inode, new_block, epos);
2030 		if (err)
2031 			return err;
2032 	}
2033 
2034 	return __udf_add_aext(inode, epos, eloc, elen, inc);
2035 }
2036 
2037 void udf_write_aext(struct inode *inode, struct extent_position *epos,
2038 		    struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2039 {
2040 	int adsize;
2041 	uint8_t *ptr;
2042 	struct short_ad *sad;
2043 	struct long_ad *lad;
2044 	struct udf_inode_info *iinfo = UDF_I(inode);
2045 
2046 	if (!epos->bh)
2047 		ptr = iinfo->i_ext.i_data + epos->offset -
2048 			udf_file_entry_alloc_offset(inode) +
2049 			iinfo->i_lenEAttr;
2050 	else
2051 		ptr = epos->bh->b_data + epos->offset;
2052 
2053 	switch (iinfo->i_alloc_type) {
2054 	case ICBTAG_FLAG_AD_SHORT:
2055 		sad = (struct short_ad *)ptr;
2056 		sad->extLength = cpu_to_le32(elen);
2057 		sad->extPosition = cpu_to_le32(eloc->logicalBlockNum);
2058 		adsize = sizeof(struct short_ad);
2059 		break;
2060 	case ICBTAG_FLAG_AD_LONG:
2061 		lad = (struct long_ad *)ptr;
2062 		lad->extLength = cpu_to_le32(elen);
2063 		lad->extLocation = cpu_to_lelb(*eloc);
2064 		memset(lad->impUse, 0x00, sizeof(lad->impUse));
2065 		adsize = sizeof(struct long_ad);
2066 		break;
2067 	default:
2068 		return;
2069 	}
2070 
2071 	if (epos->bh) {
2072 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2073 		    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201) {
2074 			struct allocExtDesc *aed =
2075 				(struct allocExtDesc *)epos->bh->b_data;
2076 			udf_update_tag(epos->bh->b_data,
2077 				       le32_to_cpu(aed->lengthAllocDescs) +
2078 				       sizeof(struct allocExtDesc));
2079 		}
2080 		mark_buffer_dirty_inode(epos->bh, inode);
2081 	} else {
2082 		mark_inode_dirty(inode);
2083 	}
2084 
2085 	if (inc)
2086 		epos->offset += adsize;
2087 }
2088 
2089 /*
2090  * Only 1 indirect extent in a row really makes sense but allow upto 16 in case
2091  * someone does some weird stuff.
2092  */
2093 #define UDF_MAX_INDIR_EXTS 16
2094 
2095 int8_t udf_next_aext(struct inode *inode, struct extent_position *epos,
2096 		     struct kernel_lb_addr *eloc, uint32_t *elen, int inc)
2097 {
2098 	int8_t etype;
2099 	unsigned int indirections = 0;
2100 
2101 	while ((etype = udf_current_aext(inode, epos, eloc, elen, inc)) ==
2102 	       (EXT_NEXT_EXTENT_ALLOCDECS >> 30)) {
2103 		int block;
2104 
2105 		if (++indirections > UDF_MAX_INDIR_EXTS) {
2106 			udf_err(inode->i_sb,
2107 				"too many indirect extents in inode %lu\n",
2108 				inode->i_ino);
2109 			return -1;
2110 		}
2111 
2112 		epos->block = *eloc;
2113 		epos->offset = sizeof(struct allocExtDesc);
2114 		brelse(epos->bh);
2115 		block = udf_get_lb_pblock(inode->i_sb, &epos->block, 0);
2116 		epos->bh = udf_tread(inode->i_sb, block);
2117 		if (!epos->bh) {
2118 			udf_debug("reading block %d failed!\n", block);
2119 			return -1;
2120 		}
2121 	}
2122 
2123 	return etype;
2124 }
2125 
2126 int8_t udf_current_aext(struct inode *inode, struct extent_position *epos,
2127 			struct kernel_lb_addr *eloc, uint32_t *elen, int inc)
2128 {
2129 	int alen;
2130 	int8_t etype;
2131 	uint8_t *ptr;
2132 	struct short_ad *sad;
2133 	struct long_ad *lad;
2134 	struct udf_inode_info *iinfo = UDF_I(inode);
2135 
2136 	if (!epos->bh) {
2137 		if (!epos->offset)
2138 			epos->offset = udf_file_entry_alloc_offset(inode);
2139 		ptr = iinfo->i_ext.i_data + epos->offset -
2140 			udf_file_entry_alloc_offset(inode) +
2141 			iinfo->i_lenEAttr;
2142 		alen = udf_file_entry_alloc_offset(inode) +
2143 							iinfo->i_lenAlloc;
2144 	} else {
2145 		if (!epos->offset)
2146 			epos->offset = sizeof(struct allocExtDesc);
2147 		ptr = epos->bh->b_data + epos->offset;
2148 		alen = sizeof(struct allocExtDesc) +
2149 			le32_to_cpu(((struct allocExtDesc *)epos->bh->b_data)->
2150 							lengthAllocDescs);
2151 	}
2152 
2153 	switch (iinfo->i_alloc_type) {
2154 	case ICBTAG_FLAG_AD_SHORT:
2155 		sad = udf_get_fileshortad(ptr, alen, &epos->offset, inc);
2156 		if (!sad)
2157 			return -1;
2158 		etype = le32_to_cpu(sad->extLength) >> 30;
2159 		eloc->logicalBlockNum = le32_to_cpu(sad->extPosition);
2160 		eloc->partitionReferenceNum =
2161 				iinfo->i_location.partitionReferenceNum;
2162 		*elen = le32_to_cpu(sad->extLength) & UDF_EXTENT_LENGTH_MASK;
2163 		break;
2164 	case ICBTAG_FLAG_AD_LONG:
2165 		lad = udf_get_filelongad(ptr, alen, &epos->offset, inc);
2166 		if (!lad)
2167 			return -1;
2168 		etype = le32_to_cpu(lad->extLength) >> 30;
2169 		*eloc = lelb_to_cpu(lad->extLocation);
2170 		*elen = le32_to_cpu(lad->extLength) & UDF_EXTENT_LENGTH_MASK;
2171 		break;
2172 	default:
2173 		udf_debug("alloc_type = %d unsupported\n", iinfo->i_alloc_type);
2174 		return -1;
2175 	}
2176 
2177 	return etype;
2178 }
2179 
2180 static int8_t udf_insert_aext(struct inode *inode, struct extent_position epos,
2181 			      struct kernel_lb_addr neloc, uint32_t nelen)
2182 {
2183 	struct kernel_lb_addr oeloc;
2184 	uint32_t oelen;
2185 	int8_t etype;
2186 
2187 	if (epos.bh)
2188 		get_bh(epos.bh);
2189 
2190 	while ((etype = udf_next_aext(inode, &epos, &oeloc, &oelen, 0)) != -1) {
2191 		udf_write_aext(inode, &epos, &neloc, nelen, 1);
2192 		neloc = oeloc;
2193 		nelen = (etype << 30) | oelen;
2194 	}
2195 	udf_add_aext(inode, &epos, &neloc, nelen, 1);
2196 	brelse(epos.bh);
2197 
2198 	return (nelen >> 30);
2199 }
2200 
2201 int8_t udf_delete_aext(struct inode *inode, struct extent_position epos,
2202 		       struct kernel_lb_addr eloc, uint32_t elen)
2203 {
2204 	struct extent_position oepos;
2205 	int adsize;
2206 	int8_t etype;
2207 	struct allocExtDesc *aed;
2208 	struct udf_inode_info *iinfo;
2209 
2210 	if (epos.bh) {
2211 		get_bh(epos.bh);
2212 		get_bh(epos.bh);
2213 	}
2214 
2215 	iinfo = UDF_I(inode);
2216 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2217 		adsize = sizeof(struct short_ad);
2218 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2219 		adsize = sizeof(struct long_ad);
2220 	else
2221 		adsize = 0;
2222 
2223 	oepos = epos;
2224 	if (udf_next_aext(inode, &epos, &eloc, &elen, 1) == -1)
2225 		return -1;
2226 
2227 	while ((etype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1) {
2228 		udf_write_aext(inode, &oepos, &eloc, (etype << 30) | elen, 1);
2229 		if (oepos.bh != epos.bh) {
2230 			oepos.block = epos.block;
2231 			brelse(oepos.bh);
2232 			get_bh(epos.bh);
2233 			oepos.bh = epos.bh;
2234 			oepos.offset = epos.offset - adsize;
2235 		}
2236 	}
2237 	memset(&eloc, 0x00, sizeof(struct kernel_lb_addr));
2238 	elen = 0;
2239 
2240 	if (epos.bh != oepos.bh) {
2241 		udf_free_blocks(inode->i_sb, inode, &epos.block, 0, 1);
2242 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2243 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2244 		if (!oepos.bh) {
2245 			iinfo->i_lenAlloc -= (adsize * 2);
2246 			mark_inode_dirty(inode);
2247 		} else {
2248 			aed = (struct allocExtDesc *)oepos.bh->b_data;
2249 			le32_add_cpu(&aed->lengthAllocDescs, -(2 * adsize));
2250 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2251 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2252 				udf_update_tag(oepos.bh->b_data,
2253 						oepos.offset - (2 * adsize));
2254 			else
2255 				udf_update_tag(oepos.bh->b_data,
2256 						sizeof(struct allocExtDesc));
2257 			mark_buffer_dirty_inode(oepos.bh, inode);
2258 		}
2259 	} else {
2260 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2261 		if (!oepos.bh) {
2262 			iinfo->i_lenAlloc -= adsize;
2263 			mark_inode_dirty(inode);
2264 		} else {
2265 			aed = (struct allocExtDesc *)oepos.bh->b_data;
2266 			le32_add_cpu(&aed->lengthAllocDescs, -adsize);
2267 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2268 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2269 				udf_update_tag(oepos.bh->b_data,
2270 						epos.offset - adsize);
2271 			else
2272 				udf_update_tag(oepos.bh->b_data,
2273 						sizeof(struct allocExtDesc));
2274 			mark_buffer_dirty_inode(oepos.bh, inode);
2275 		}
2276 	}
2277 
2278 	brelse(epos.bh);
2279 	brelse(oepos.bh);
2280 
2281 	return (elen >> 30);
2282 }
2283 
2284 int8_t inode_bmap(struct inode *inode, sector_t block,
2285 		  struct extent_position *pos, struct kernel_lb_addr *eloc,
2286 		  uint32_t *elen, sector_t *offset)
2287 {
2288 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
2289 	loff_t lbcount = 0, bcount =
2290 	    (loff_t) block << blocksize_bits;
2291 	int8_t etype;
2292 	struct udf_inode_info *iinfo;
2293 
2294 	iinfo = UDF_I(inode);
2295 	if (!udf_read_extent_cache(inode, bcount, &lbcount, pos)) {
2296 		pos->offset = 0;
2297 		pos->block = iinfo->i_location;
2298 		pos->bh = NULL;
2299 	}
2300 	*elen = 0;
2301 	do {
2302 		etype = udf_next_aext(inode, pos, eloc, elen, 1);
2303 		if (etype == -1) {
2304 			*offset = (bcount - lbcount) >> blocksize_bits;
2305 			iinfo->i_lenExtents = lbcount;
2306 			return -1;
2307 		}
2308 		lbcount += *elen;
2309 	} while (lbcount <= bcount);
2310 	/* update extent cache */
2311 	udf_update_extent_cache(inode, lbcount - *elen, pos, 1);
2312 	*offset = (bcount + *elen - lbcount) >> blocksize_bits;
2313 
2314 	return etype;
2315 }
2316 
2317 long udf_block_map(struct inode *inode, sector_t block)
2318 {
2319 	struct kernel_lb_addr eloc;
2320 	uint32_t elen;
2321 	sector_t offset;
2322 	struct extent_position epos = {};
2323 	int ret;
2324 
2325 	down_read(&UDF_I(inode)->i_data_sem);
2326 
2327 	if (inode_bmap(inode, block, &epos, &eloc, &elen, &offset) ==
2328 						(EXT_RECORDED_ALLOCATED >> 30))
2329 		ret = udf_get_lb_pblock(inode->i_sb, &eloc, offset);
2330 	else
2331 		ret = 0;
2332 
2333 	up_read(&UDF_I(inode)->i_data_sem);
2334 	brelse(epos.bh);
2335 
2336 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_VARCONV))
2337 		return udf_fixed_to_variable(ret);
2338 	else
2339 		return ret;
2340 }
2341