xref: /openbmc/linux/fs/udf/inode.c (revision 5cfc4532)
1 /*
2  * inode.c
3  *
4  * PURPOSE
5  *  Inode handling routines for the OSTA-UDF(tm) filesystem.
6  *
7  * COPYRIGHT
8  *  This file is distributed under the terms of the GNU General Public
9  *  License (GPL). Copies of the GPL can be obtained from:
10  *    ftp://prep.ai.mit.edu/pub/gnu/GPL
11  *  Each contributing author retains all rights to their own work.
12  *
13  *  (C) 1998 Dave Boynton
14  *  (C) 1998-2004 Ben Fennema
15  *  (C) 1999-2000 Stelias Computing Inc
16  *
17  * HISTORY
18  *
19  *  10/04/98 dgb  Added rudimentary directory functions
20  *  10/07/98      Fully working udf_block_map! It works!
21  *  11/25/98      bmap altered to better support extents
22  *  12/06/98 blf  partition support in udf_iget, udf_block_map
23  *                and udf_read_inode
24  *  12/12/98      rewrote udf_block_map to handle next extents and descs across
25  *                block boundaries (which is not actually allowed)
26  *  12/20/98      added support for strategy 4096
27  *  03/07/99      rewrote udf_block_map (again)
28  *                New funcs, inode_bmap, udf_next_aext
29  *  04/19/99      Support for writing device EA's for major/minor #
30  */
31 
32 #include "udfdecl.h"
33 #include <linux/mm.h>
34 #include <linux/module.h>
35 #include <linux/pagemap.h>
36 #include <linux/writeback.h>
37 #include <linux/slab.h>
38 #include <linux/crc-itu-t.h>
39 #include <linux/mpage.h>
40 #include <linux/uio.h>
41 #include <linux/bio.h>
42 
43 #include "udf_i.h"
44 #include "udf_sb.h"
45 
46 #define EXTENT_MERGE_SIZE 5
47 
48 #define FE_MAPPED_PERMS	(FE_PERM_U_READ | FE_PERM_U_WRITE | FE_PERM_U_EXEC | \
49 			 FE_PERM_G_READ | FE_PERM_G_WRITE | FE_PERM_G_EXEC | \
50 			 FE_PERM_O_READ | FE_PERM_O_WRITE | FE_PERM_O_EXEC)
51 
52 #define FE_DELETE_PERMS	(FE_PERM_U_DELETE | FE_PERM_G_DELETE | \
53 			 FE_PERM_O_DELETE)
54 
55 struct udf_map_rq;
56 
57 static umode_t udf_convert_permissions(struct fileEntry *);
58 static int udf_update_inode(struct inode *, int);
59 static int udf_sync_inode(struct inode *inode);
60 static int udf_alloc_i_data(struct inode *inode, size_t size);
61 static int inode_getblk(struct inode *inode, struct udf_map_rq *map);
62 static int udf_insert_aext(struct inode *, struct extent_position,
63 			   struct kernel_lb_addr, uint32_t);
64 static void udf_split_extents(struct inode *, int *, int, udf_pblk_t,
65 			      struct kernel_long_ad *, int *);
66 static void udf_prealloc_extents(struct inode *, int, int,
67 				 struct kernel_long_ad *, int *);
68 static void udf_merge_extents(struct inode *, struct kernel_long_ad *, int *);
69 static int udf_update_extents(struct inode *, struct kernel_long_ad *, int,
70 			      int, struct extent_position *);
71 static int udf_get_block_wb(struct inode *inode, sector_t block,
72 			    struct buffer_head *bh_result, int create);
73 
74 static void __udf_clear_extent_cache(struct inode *inode)
75 {
76 	struct udf_inode_info *iinfo = UDF_I(inode);
77 
78 	if (iinfo->cached_extent.lstart != -1) {
79 		brelse(iinfo->cached_extent.epos.bh);
80 		iinfo->cached_extent.lstart = -1;
81 	}
82 }
83 
84 /* Invalidate extent cache */
85 static void udf_clear_extent_cache(struct inode *inode)
86 {
87 	struct udf_inode_info *iinfo = UDF_I(inode);
88 
89 	spin_lock(&iinfo->i_extent_cache_lock);
90 	__udf_clear_extent_cache(inode);
91 	spin_unlock(&iinfo->i_extent_cache_lock);
92 }
93 
94 /* Return contents of extent cache */
95 static int udf_read_extent_cache(struct inode *inode, loff_t bcount,
96 				 loff_t *lbcount, struct extent_position *pos)
97 {
98 	struct udf_inode_info *iinfo = UDF_I(inode);
99 	int ret = 0;
100 
101 	spin_lock(&iinfo->i_extent_cache_lock);
102 	if ((iinfo->cached_extent.lstart <= bcount) &&
103 	    (iinfo->cached_extent.lstart != -1)) {
104 		/* Cache hit */
105 		*lbcount = iinfo->cached_extent.lstart;
106 		memcpy(pos, &iinfo->cached_extent.epos,
107 		       sizeof(struct extent_position));
108 		if (pos->bh)
109 			get_bh(pos->bh);
110 		ret = 1;
111 	}
112 	spin_unlock(&iinfo->i_extent_cache_lock);
113 	return ret;
114 }
115 
116 /* Add extent to extent cache */
117 static void udf_update_extent_cache(struct inode *inode, loff_t estart,
118 				    struct extent_position *pos)
119 {
120 	struct udf_inode_info *iinfo = UDF_I(inode);
121 
122 	spin_lock(&iinfo->i_extent_cache_lock);
123 	/* Invalidate previously cached extent */
124 	__udf_clear_extent_cache(inode);
125 	if (pos->bh)
126 		get_bh(pos->bh);
127 	memcpy(&iinfo->cached_extent.epos, pos, sizeof(*pos));
128 	iinfo->cached_extent.lstart = estart;
129 	switch (iinfo->i_alloc_type) {
130 	case ICBTAG_FLAG_AD_SHORT:
131 		iinfo->cached_extent.epos.offset -= sizeof(struct short_ad);
132 		break;
133 	case ICBTAG_FLAG_AD_LONG:
134 		iinfo->cached_extent.epos.offset -= sizeof(struct long_ad);
135 		break;
136 	}
137 	spin_unlock(&iinfo->i_extent_cache_lock);
138 }
139 
140 void udf_evict_inode(struct inode *inode)
141 {
142 	struct udf_inode_info *iinfo = UDF_I(inode);
143 	int want_delete = 0;
144 
145 	if (!is_bad_inode(inode)) {
146 		if (!inode->i_nlink) {
147 			want_delete = 1;
148 			udf_setsize(inode, 0);
149 			udf_update_inode(inode, IS_SYNC(inode));
150 		}
151 		if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB &&
152 		    inode->i_size != iinfo->i_lenExtents) {
153 			udf_warn(inode->i_sb,
154 				 "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 	}
160 	truncate_inode_pages_final(&inode->i_data);
161 	invalidate_inode_buffers(inode);
162 	clear_inode(inode);
163 	kfree(iinfo->i_data);
164 	iinfo->i_data = NULL;
165 	udf_clear_extent_cache(inode);
166 	if (want_delete) {
167 		udf_free_inode(inode);
168 	}
169 }
170 
171 static void udf_write_failed(struct address_space *mapping, loff_t to)
172 {
173 	struct inode *inode = mapping->host;
174 	struct udf_inode_info *iinfo = UDF_I(inode);
175 	loff_t isize = inode->i_size;
176 
177 	if (to > isize) {
178 		truncate_pagecache(inode, isize);
179 		if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
180 			down_write(&iinfo->i_data_sem);
181 			udf_clear_extent_cache(inode);
182 			udf_truncate_extents(inode);
183 			up_write(&iinfo->i_data_sem);
184 		}
185 	}
186 }
187 
188 static int udf_adinicb_writepage(struct page *page,
189 				 struct writeback_control *wbc, void *data)
190 {
191 	struct inode *inode = page->mapping->host;
192 	struct udf_inode_info *iinfo = UDF_I(inode);
193 
194 	BUG_ON(!PageLocked(page));
195 	memcpy_to_page(page, 0, iinfo->i_data + iinfo->i_lenEAttr,
196 		       i_size_read(inode));
197 	unlock_page(page);
198 	mark_inode_dirty(inode);
199 
200 	return 0;
201 }
202 
203 static int udf_writepages(struct address_space *mapping,
204 			  struct writeback_control *wbc)
205 {
206 	struct inode *inode = mapping->host;
207 	struct udf_inode_info *iinfo = UDF_I(inode);
208 
209 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB)
210 		return mpage_writepages(mapping, wbc, udf_get_block_wb);
211 	return write_cache_pages(mapping, wbc, udf_adinicb_writepage, NULL);
212 }
213 
214 static void udf_adinicb_readpage(struct page *page)
215 {
216 	struct inode *inode = page->mapping->host;
217 	char *kaddr;
218 	struct udf_inode_info *iinfo = UDF_I(inode);
219 	loff_t isize = i_size_read(inode);
220 
221 	kaddr = kmap_local_page(page);
222 	memcpy(kaddr, iinfo->i_data + iinfo->i_lenEAttr, isize);
223 	memset(kaddr + isize, 0, PAGE_SIZE - isize);
224 	flush_dcache_page(page);
225 	SetPageUptodate(page);
226 	kunmap_local(kaddr);
227 }
228 
229 static int udf_read_folio(struct file *file, struct folio *folio)
230 {
231 	struct udf_inode_info *iinfo = UDF_I(file_inode(file));
232 
233 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
234 		udf_adinicb_readpage(&folio->page);
235 		folio_unlock(folio);
236 		return 0;
237 	}
238 	return mpage_read_folio(folio, udf_get_block);
239 }
240 
241 static void udf_readahead(struct readahead_control *rac)
242 {
243 	mpage_readahead(rac, udf_get_block);
244 }
245 
246 static int udf_write_begin(struct file *file, struct address_space *mapping,
247 			   loff_t pos, unsigned len,
248 			   struct page **pagep, void **fsdata)
249 {
250 	struct udf_inode_info *iinfo = UDF_I(file_inode(file));
251 	struct page *page;
252 	int ret;
253 
254 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
255 		ret = block_write_begin(mapping, pos, len, pagep,
256 					udf_get_block);
257 		if (unlikely(ret))
258 			udf_write_failed(mapping, pos + len);
259 		return ret;
260 	}
261 	if (WARN_ON_ONCE(pos >= PAGE_SIZE))
262 		return -EIO;
263 	page = grab_cache_page_write_begin(mapping, 0);
264 	if (!page)
265 		return -ENOMEM;
266 	*pagep = page;
267 	if (!PageUptodate(page))
268 		udf_adinicb_readpage(page);
269 	return 0;
270 }
271 
272 static int udf_write_end(struct file *file, struct address_space *mapping,
273 			 loff_t pos, unsigned len, unsigned copied,
274 			 struct page *page, void *fsdata)
275 {
276 	struct inode *inode = file_inode(file);
277 	loff_t last_pos;
278 
279 	if (UDF_I(inode)->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB)
280 		return generic_write_end(file, mapping, pos, len, copied, page,
281 					 fsdata);
282 	last_pos = pos + copied;
283 	if (last_pos > inode->i_size)
284 		i_size_write(inode, last_pos);
285 	set_page_dirty(page);
286 	unlock_page(page);
287 	put_page(page);
288 
289 	return copied;
290 }
291 
292 static ssize_t udf_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
293 {
294 	struct file *file = iocb->ki_filp;
295 	struct address_space *mapping = file->f_mapping;
296 	struct inode *inode = mapping->host;
297 	size_t count = iov_iter_count(iter);
298 	ssize_t ret;
299 
300 	/* Fallback to buffered IO for in-ICB files */
301 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
302 		return 0;
303 	ret = blockdev_direct_IO(iocb, inode, iter, udf_get_block);
304 	if (unlikely(ret < 0 && iov_iter_rw(iter) == WRITE))
305 		udf_write_failed(mapping, iocb->ki_pos + count);
306 	return ret;
307 }
308 
309 static sector_t udf_bmap(struct address_space *mapping, sector_t block)
310 {
311 	struct udf_inode_info *iinfo = UDF_I(mapping->host);
312 
313 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
314 		return -EINVAL;
315 	return generic_block_bmap(mapping, block, udf_get_block);
316 }
317 
318 const struct address_space_operations udf_aops = {
319 	.dirty_folio	= block_dirty_folio,
320 	.invalidate_folio = block_invalidate_folio,
321 	.read_folio	= udf_read_folio,
322 	.readahead	= udf_readahead,
323 	.writepages	= udf_writepages,
324 	.write_begin	= udf_write_begin,
325 	.write_end	= udf_write_end,
326 	.direct_IO	= udf_direct_IO,
327 	.bmap		= udf_bmap,
328 	.migrate_folio	= buffer_migrate_folio,
329 };
330 
331 /*
332  * Expand file stored in ICB to a normal one-block-file
333  *
334  * This function requires i_mutex held
335  */
336 int udf_expand_file_adinicb(struct inode *inode)
337 {
338 	struct page *page;
339 	char *kaddr;
340 	struct udf_inode_info *iinfo = UDF_I(inode);
341 	int err;
342 
343 	WARN_ON_ONCE(!inode_is_locked(inode));
344 	if (!iinfo->i_lenAlloc) {
345 		down_write(&iinfo->i_data_sem);
346 		if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
347 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
348 		else
349 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
350 		/* from now on we have normal address_space methods */
351 		inode->i_data.a_ops = &udf_aops;
352 		up_write(&iinfo->i_data_sem);
353 		mark_inode_dirty(inode);
354 		return 0;
355 	}
356 
357 	page = find_or_create_page(inode->i_mapping, 0, GFP_NOFS);
358 	if (!page)
359 		return -ENOMEM;
360 
361 	if (!PageUptodate(page)) {
362 		kaddr = kmap_atomic(page);
363 		memset(kaddr + iinfo->i_lenAlloc, 0x00,
364 		       PAGE_SIZE - iinfo->i_lenAlloc);
365 		memcpy(kaddr, iinfo->i_data + iinfo->i_lenEAttr,
366 			iinfo->i_lenAlloc);
367 		flush_dcache_page(page);
368 		SetPageUptodate(page);
369 		kunmap_atomic(kaddr);
370 	}
371 	down_write(&iinfo->i_data_sem);
372 	memset(iinfo->i_data + iinfo->i_lenEAttr, 0x00,
373 	       iinfo->i_lenAlloc);
374 	iinfo->i_lenAlloc = 0;
375 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
376 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
377 	else
378 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
379 	set_page_dirty(page);
380 	unlock_page(page);
381 	up_write(&iinfo->i_data_sem);
382 	err = filemap_fdatawrite(inode->i_mapping);
383 	if (err) {
384 		/* Restore everything back so that we don't lose data... */
385 		lock_page(page);
386 		down_write(&iinfo->i_data_sem);
387 		kaddr = kmap_atomic(page);
388 		memcpy(iinfo->i_data + iinfo->i_lenEAttr, kaddr, inode->i_size);
389 		kunmap_atomic(kaddr);
390 		unlock_page(page);
391 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
392 		iinfo->i_lenAlloc = inode->i_size;
393 		up_write(&iinfo->i_data_sem);
394 	}
395 	put_page(page);
396 	mark_inode_dirty(inode);
397 
398 	return err;
399 }
400 
401 #define UDF_MAP_CREATE		0x01	/* Mapping can allocate new blocks */
402 #define UDF_MAP_NOPREALLOC	0x02	/* Do not preallocate blocks */
403 
404 #define UDF_BLK_MAPPED	0x01	/* Block was successfully mapped */
405 #define UDF_BLK_NEW	0x02	/* Block was freshly allocated */
406 
407 struct udf_map_rq {
408 	sector_t lblk;
409 	udf_pblk_t pblk;
410 	int iflags;		/* UDF_MAP_ flags determining behavior */
411 	int oflags;		/* UDF_BLK_ flags reporting results */
412 };
413 
414 static int udf_map_block(struct inode *inode, struct udf_map_rq *map)
415 {
416 	int err;
417 	struct udf_inode_info *iinfo = UDF_I(inode);
418 
419 	map->oflags = 0;
420 	if (!(map->iflags & UDF_MAP_CREATE)) {
421 		struct kernel_lb_addr eloc;
422 		uint32_t elen;
423 		sector_t offset;
424 		struct extent_position epos = {};
425 
426 		down_read(&iinfo->i_data_sem);
427 		if (inode_bmap(inode, map->lblk, &epos, &eloc, &elen, &offset)
428 				== (EXT_RECORDED_ALLOCATED >> 30)) {
429 			map->pblk = udf_get_lb_pblock(inode->i_sb, &eloc,
430 							offset);
431 			map->oflags |= UDF_BLK_MAPPED;
432 		}
433 		up_read(&iinfo->i_data_sem);
434 		brelse(epos.bh);
435 
436 		return 0;
437 	}
438 
439 	down_write(&iinfo->i_data_sem);
440 	/*
441 	 * Block beyond EOF and prealloc extents? Just discard preallocation
442 	 * as it is not useful and complicates things.
443 	 */
444 	if (((loff_t)map->lblk) << inode->i_blkbits >= iinfo->i_lenExtents)
445 		udf_discard_prealloc(inode);
446 	udf_clear_extent_cache(inode);
447 	err = inode_getblk(inode, map);
448 	up_write(&iinfo->i_data_sem);
449 	return err;
450 }
451 
452 static int __udf_get_block(struct inode *inode, sector_t block,
453 			   struct buffer_head *bh_result, int flags)
454 {
455 	int err;
456 	struct udf_map_rq map = {
457 		.lblk = block,
458 		.iflags = flags,
459 	};
460 
461 	err = udf_map_block(inode, &map);
462 	if (err < 0)
463 		return err;
464 	if (map.oflags & UDF_BLK_MAPPED) {
465 		map_bh(bh_result, inode->i_sb, map.pblk);
466 		if (map.oflags & UDF_BLK_NEW)
467 			set_buffer_new(bh_result);
468 	}
469 	return 0;
470 }
471 
472 int udf_get_block(struct inode *inode, sector_t block,
473 		  struct buffer_head *bh_result, int create)
474 {
475 	int flags = create ? UDF_MAP_CREATE : 0;
476 
477 	/*
478 	 * We preallocate blocks only for regular files. It also makes sense
479 	 * for directories but there's a problem when to drop the
480 	 * preallocation. We might use some delayed work for that but I feel
481 	 * it's overengineering for a filesystem like UDF.
482 	 */
483 	if (!S_ISREG(inode->i_mode))
484 		flags |= UDF_MAP_NOPREALLOC;
485 	return __udf_get_block(inode, block, bh_result, flags);
486 }
487 
488 /*
489  * We shouldn't be allocating blocks on page writeback since we allocate them
490  * on page fault. We can spot dirty buffers without allocated blocks though
491  * when truncate expands file. These however don't have valid data so we can
492  * safely ignore them. So never allocate blocks from page writeback.
493  */
494 static int udf_get_block_wb(struct inode *inode, sector_t block,
495 			    struct buffer_head *bh_result, int create)
496 {
497 	return __udf_get_block(inode, block, bh_result, 0);
498 }
499 
500 /* Extend the file with new blocks totaling 'new_block_bytes',
501  * return the number of extents added
502  */
503 static int udf_do_extend_file(struct inode *inode,
504 			      struct extent_position *last_pos,
505 			      struct kernel_long_ad *last_ext,
506 			      loff_t new_block_bytes)
507 {
508 	uint32_t add;
509 	int count = 0, fake = !(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
510 	struct super_block *sb = inode->i_sb;
511 	struct udf_inode_info *iinfo;
512 	int err;
513 
514 	/* The previous extent is fake and we should not extend by anything
515 	 * - there's nothing to do... */
516 	if (!new_block_bytes && fake)
517 		return 0;
518 
519 	iinfo = UDF_I(inode);
520 	/* Round the last extent up to a multiple of block size */
521 	if (last_ext->extLength & (sb->s_blocksize - 1)) {
522 		last_ext->extLength =
523 			(last_ext->extLength & UDF_EXTENT_FLAG_MASK) |
524 			(((last_ext->extLength & UDF_EXTENT_LENGTH_MASK) +
525 			  sb->s_blocksize - 1) & ~(sb->s_blocksize - 1));
526 		iinfo->i_lenExtents =
527 			(iinfo->i_lenExtents + sb->s_blocksize - 1) &
528 			~(sb->s_blocksize - 1);
529 	}
530 
531 	add = 0;
532 	/* Can we merge with the previous extent? */
533 	if ((last_ext->extLength & UDF_EXTENT_FLAG_MASK) ==
534 					EXT_NOT_RECORDED_NOT_ALLOCATED) {
535 		add = (1 << 30) - sb->s_blocksize -
536 			(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
537 		if (add > new_block_bytes)
538 			add = new_block_bytes;
539 		new_block_bytes -= add;
540 		last_ext->extLength += add;
541 	}
542 
543 	if (fake) {
544 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
545 				   last_ext->extLength, 1);
546 		if (err < 0)
547 			goto out_err;
548 		count++;
549 	} else {
550 		struct kernel_lb_addr tmploc;
551 		uint32_t tmplen;
552 
553 		udf_write_aext(inode, last_pos, &last_ext->extLocation,
554 				last_ext->extLength, 1);
555 
556 		/*
557 		 * We've rewritten the last extent. If we are going to add
558 		 * more extents, we may need to enter possible following
559 		 * empty indirect extent.
560 		 */
561 		if (new_block_bytes)
562 			udf_next_aext(inode, last_pos, &tmploc, &tmplen, 0);
563 	}
564 	iinfo->i_lenExtents += add;
565 
566 	/* Managed to do everything necessary? */
567 	if (!new_block_bytes)
568 		goto out;
569 
570 	/* All further extents will be NOT_RECORDED_NOT_ALLOCATED */
571 	last_ext->extLocation.logicalBlockNum = 0;
572 	last_ext->extLocation.partitionReferenceNum = 0;
573 	add = (1 << 30) - sb->s_blocksize;
574 	last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED | add;
575 
576 	/* Create enough extents to cover the whole hole */
577 	while (new_block_bytes > add) {
578 		new_block_bytes -= add;
579 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
580 				   last_ext->extLength, 1);
581 		if (err)
582 			goto out_err;
583 		iinfo->i_lenExtents += add;
584 		count++;
585 	}
586 	if (new_block_bytes) {
587 		last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
588 			new_block_bytes;
589 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
590 				   last_ext->extLength, 1);
591 		if (err)
592 			goto out_err;
593 		iinfo->i_lenExtents += new_block_bytes;
594 		count++;
595 	}
596 
597 out:
598 	/* last_pos should point to the last written extent... */
599 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
600 		last_pos->offset -= sizeof(struct short_ad);
601 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
602 		last_pos->offset -= sizeof(struct long_ad);
603 	else
604 		return -EIO;
605 
606 	return count;
607 out_err:
608 	/* Remove extents we've created so far */
609 	udf_clear_extent_cache(inode);
610 	udf_truncate_extents(inode);
611 	return err;
612 }
613 
614 /* Extend the final block of the file to final_block_len bytes */
615 static void udf_do_extend_final_block(struct inode *inode,
616 				      struct extent_position *last_pos,
617 				      struct kernel_long_ad *last_ext,
618 				      uint32_t new_elen)
619 {
620 	uint32_t added_bytes;
621 
622 	/*
623 	 * Extent already large enough? It may be already rounded up to block
624 	 * size...
625 	 */
626 	if (new_elen <= (last_ext->extLength & UDF_EXTENT_LENGTH_MASK))
627 		return;
628 	added_bytes = new_elen - (last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
629 	last_ext->extLength += added_bytes;
630 	UDF_I(inode)->i_lenExtents += added_bytes;
631 
632 	udf_write_aext(inode, last_pos, &last_ext->extLocation,
633 			last_ext->extLength, 1);
634 }
635 
636 static int udf_extend_file(struct inode *inode, loff_t newsize)
637 {
638 
639 	struct extent_position epos;
640 	struct kernel_lb_addr eloc;
641 	uint32_t elen;
642 	int8_t etype;
643 	struct super_block *sb = inode->i_sb;
644 	sector_t first_block = newsize >> sb->s_blocksize_bits, offset;
645 	loff_t new_elen;
646 	int adsize;
647 	struct udf_inode_info *iinfo = UDF_I(inode);
648 	struct kernel_long_ad extent;
649 	int err = 0;
650 	bool within_last_ext;
651 
652 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
653 		adsize = sizeof(struct short_ad);
654 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
655 		adsize = sizeof(struct long_ad);
656 	else
657 		BUG();
658 
659 	down_write(&iinfo->i_data_sem);
660 	/*
661 	 * When creating hole in file, just don't bother with preserving
662 	 * preallocation. It likely won't be very useful anyway.
663 	 */
664 	udf_discard_prealloc(inode);
665 
666 	etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset);
667 	within_last_ext = (etype != -1);
668 	/* We don't expect extents past EOF... */
669 	WARN_ON_ONCE(within_last_ext &&
670 		     elen > ((loff_t)offset + 1) << inode->i_blkbits);
671 
672 	if ((!epos.bh && epos.offset == udf_file_entry_alloc_offset(inode)) ||
673 	    (epos.bh && epos.offset == sizeof(struct allocExtDesc))) {
674 		/* File has no extents at all or has empty last
675 		 * indirect extent! Create a fake extent... */
676 		extent.extLocation.logicalBlockNum = 0;
677 		extent.extLocation.partitionReferenceNum = 0;
678 		extent.extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
679 	} else {
680 		epos.offset -= adsize;
681 		etype = udf_next_aext(inode, &epos, &extent.extLocation,
682 				      &extent.extLength, 0);
683 		extent.extLength |= etype << 30;
684 	}
685 
686 	new_elen = ((loff_t)offset << inode->i_blkbits) |
687 					(newsize & (sb->s_blocksize - 1));
688 
689 	/* File has extent covering the new size (could happen when extending
690 	 * inside a block)?
691 	 */
692 	if (within_last_ext) {
693 		/* Extending file within the last file block */
694 		udf_do_extend_final_block(inode, &epos, &extent, new_elen);
695 	} else {
696 		err = udf_do_extend_file(inode, &epos, &extent, new_elen);
697 	}
698 
699 	if (err < 0)
700 		goto out;
701 	err = 0;
702 out:
703 	brelse(epos.bh);
704 	up_write(&iinfo->i_data_sem);
705 	return err;
706 }
707 
708 static int inode_getblk(struct inode *inode, struct udf_map_rq *map)
709 {
710 	struct kernel_long_ad laarr[EXTENT_MERGE_SIZE];
711 	struct extent_position prev_epos, cur_epos, next_epos;
712 	int count = 0, startnum = 0, endnum = 0;
713 	uint32_t elen = 0, tmpelen;
714 	struct kernel_lb_addr eloc, tmpeloc;
715 	int c = 1;
716 	loff_t lbcount = 0, b_off = 0;
717 	udf_pblk_t newblocknum;
718 	sector_t offset = 0;
719 	int8_t etype;
720 	struct udf_inode_info *iinfo = UDF_I(inode);
721 	udf_pblk_t goal = 0, pgoal = iinfo->i_location.logicalBlockNum;
722 	int lastblock = 0;
723 	bool isBeyondEOF;
724 	int ret = 0;
725 
726 	prev_epos.offset = udf_file_entry_alloc_offset(inode);
727 	prev_epos.block = iinfo->i_location;
728 	prev_epos.bh = NULL;
729 	cur_epos = next_epos = prev_epos;
730 	b_off = (loff_t)map->lblk << inode->i_sb->s_blocksize_bits;
731 
732 	/* find the extent which contains the block we are looking for.
733 	   alternate between laarr[0] and laarr[1] for locations of the
734 	   current extent, and the previous extent */
735 	do {
736 		if (prev_epos.bh != cur_epos.bh) {
737 			brelse(prev_epos.bh);
738 			get_bh(cur_epos.bh);
739 			prev_epos.bh = cur_epos.bh;
740 		}
741 		if (cur_epos.bh != next_epos.bh) {
742 			brelse(cur_epos.bh);
743 			get_bh(next_epos.bh);
744 			cur_epos.bh = next_epos.bh;
745 		}
746 
747 		lbcount += elen;
748 
749 		prev_epos.block = cur_epos.block;
750 		cur_epos.block = next_epos.block;
751 
752 		prev_epos.offset = cur_epos.offset;
753 		cur_epos.offset = next_epos.offset;
754 
755 		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 1);
756 		if (etype == -1)
757 			break;
758 
759 		c = !c;
760 
761 		laarr[c].extLength = (etype << 30) | elen;
762 		laarr[c].extLocation = eloc;
763 
764 		if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
765 			pgoal = eloc.logicalBlockNum +
766 				((elen + inode->i_sb->s_blocksize - 1) >>
767 				 inode->i_sb->s_blocksize_bits);
768 
769 		count++;
770 	} while (lbcount + elen <= b_off);
771 
772 	b_off -= lbcount;
773 	offset = b_off >> inode->i_sb->s_blocksize_bits;
774 	/*
775 	 * Move prev_epos and cur_epos into indirect extent if we are at
776 	 * the pointer to it
777 	 */
778 	udf_next_aext(inode, &prev_epos, &tmpeloc, &tmpelen, 0);
779 	udf_next_aext(inode, &cur_epos, &tmpeloc, &tmpelen, 0);
780 
781 	/* if the extent is allocated and recorded, return the block
782 	   if the extent is not a multiple of the blocksize, round up */
783 
784 	if (etype == (EXT_RECORDED_ALLOCATED >> 30)) {
785 		if (elen & (inode->i_sb->s_blocksize - 1)) {
786 			elen = EXT_RECORDED_ALLOCATED |
787 				((elen + inode->i_sb->s_blocksize - 1) &
788 				 ~(inode->i_sb->s_blocksize - 1));
789 			iinfo->i_lenExtents =
790 				ALIGN(iinfo->i_lenExtents,
791 				      inode->i_sb->s_blocksize);
792 			udf_write_aext(inode, &cur_epos, &eloc, elen, 1);
793 		}
794 		map->oflags = UDF_BLK_MAPPED;
795 		map->pblk = udf_get_lb_pblock(inode->i_sb, &eloc, offset);
796 		goto out_free;
797 	}
798 
799 	/* Are we beyond EOF and preallocated extent? */
800 	if (etype == -1) {
801 		loff_t hole_len;
802 
803 		isBeyondEOF = true;
804 		if (count) {
805 			if (c)
806 				laarr[0] = laarr[1];
807 			startnum = 1;
808 		} else {
809 			/* Create a fake extent when there's not one */
810 			memset(&laarr[0].extLocation, 0x00,
811 				sizeof(struct kernel_lb_addr));
812 			laarr[0].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
813 			/* Will udf_do_extend_file() create real extent from
814 			   a fake one? */
815 			startnum = (offset > 0);
816 		}
817 		/* Create extents for the hole between EOF and offset */
818 		hole_len = (loff_t)offset << inode->i_blkbits;
819 		ret = udf_do_extend_file(inode, &prev_epos, laarr, hole_len);
820 		if (ret < 0)
821 			goto out_free;
822 		c = 0;
823 		offset = 0;
824 		count += ret;
825 		/*
826 		 * Is there any real extent? - otherwise we overwrite the fake
827 		 * one...
828 		 */
829 		if (count)
830 			c = !c;
831 		laarr[c].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
832 			inode->i_sb->s_blocksize;
833 		memset(&laarr[c].extLocation, 0x00,
834 			sizeof(struct kernel_lb_addr));
835 		count++;
836 		endnum = c + 1;
837 		lastblock = 1;
838 	} else {
839 		isBeyondEOF = false;
840 		endnum = startnum = ((count > 2) ? 2 : count);
841 
842 		/* if the current extent is in position 0,
843 		   swap it with the previous */
844 		if (!c && count != 1) {
845 			laarr[2] = laarr[0];
846 			laarr[0] = laarr[1];
847 			laarr[1] = laarr[2];
848 			c = 1;
849 		}
850 
851 		/* if the current block is located in an extent,
852 		   read the next extent */
853 		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 0);
854 		if (etype != -1) {
855 			laarr[c + 1].extLength = (etype << 30) | elen;
856 			laarr[c + 1].extLocation = eloc;
857 			count++;
858 			startnum++;
859 			endnum++;
860 		} else
861 			lastblock = 1;
862 	}
863 
864 	/* if the current extent is not recorded but allocated, get the
865 	 * block in the extent corresponding to the requested block */
866 	if ((laarr[c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30))
867 		newblocknum = laarr[c].extLocation.logicalBlockNum + offset;
868 	else { /* otherwise, allocate a new block */
869 		if (iinfo->i_next_alloc_block == map->lblk)
870 			goal = iinfo->i_next_alloc_goal;
871 
872 		if (!goal) {
873 			if (!(goal = pgoal)) /* XXX: what was intended here? */
874 				goal = iinfo->i_location.logicalBlockNum + 1;
875 		}
876 
877 		newblocknum = udf_new_block(inode->i_sb, inode,
878 				iinfo->i_location.partitionReferenceNum,
879 				goal, &ret);
880 		if (!newblocknum)
881 			goto out_free;
882 		if (isBeyondEOF)
883 			iinfo->i_lenExtents += inode->i_sb->s_blocksize;
884 	}
885 
886 	/* if the extent the requsted block is located in contains multiple
887 	 * blocks, split the extent into at most three extents. blocks prior
888 	 * to requested block, requested block, and blocks after requested
889 	 * block */
890 	udf_split_extents(inode, &c, offset, newblocknum, laarr, &endnum);
891 
892 	if (!(map->iflags & UDF_MAP_NOPREALLOC))
893 		udf_prealloc_extents(inode, c, lastblock, laarr, &endnum);
894 
895 	/* merge any continuous blocks in laarr */
896 	udf_merge_extents(inode, laarr, &endnum);
897 
898 	/* write back the new extents, inserting new extents if the new number
899 	 * of extents is greater than the old number, and deleting extents if
900 	 * the new number of extents is less than the old number */
901 	ret = udf_update_extents(inode, laarr, startnum, endnum, &prev_epos);
902 	if (ret < 0)
903 		goto out_free;
904 
905 	map->pblk = udf_get_pblock(inode->i_sb, newblocknum,
906 				iinfo->i_location.partitionReferenceNum, 0);
907 	if (!map->pblk) {
908 		ret = -EFSCORRUPTED;
909 		goto out_free;
910 	}
911 	map->oflags = UDF_BLK_NEW | UDF_BLK_MAPPED;
912 	iinfo->i_next_alloc_block = map->lblk + 1;
913 	iinfo->i_next_alloc_goal = newblocknum + 1;
914 	inode->i_ctime = current_time(inode);
915 
916 	if (IS_SYNC(inode))
917 		udf_sync_inode(inode);
918 	else
919 		mark_inode_dirty(inode);
920 	ret = 0;
921 out_free:
922 	brelse(prev_epos.bh);
923 	brelse(cur_epos.bh);
924 	brelse(next_epos.bh);
925 	return ret;
926 }
927 
928 static void udf_split_extents(struct inode *inode, int *c, int offset,
929 			       udf_pblk_t newblocknum,
930 			       struct kernel_long_ad *laarr, int *endnum)
931 {
932 	unsigned long blocksize = inode->i_sb->s_blocksize;
933 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
934 
935 	if ((laarr[*c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30) ||
936 	    (laarr[*c].extLength >> 30) ==
937 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
938 		int curr = *c;
939 		int blen = ((laarr[curr].extLength & UDF_EXTENT_LENGTH_MASK) +
940 			    blocksize - 1) >> blocksize_bits;
941 		int8_t etype = (laarr[curr].extLength >> 30);
942 
943 		if (blen == 1)
944 			;
945 		else if (!offset || blen == offset + 1) {
946 			laarr[curr + 2] = laarr[curr + 1];
947 			laarr[curr + 1] = laarr[curr];
948 		} else {
949 			laarr[curr + 3] = laarr[curr + 1];
950 			laarr[curr + 2] = laarr[curr + 1] = laarr[curr];
951 		}
952 
953 		if (offset) {
954 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
955 				udf_free_blocks(inode->i_sb, inode,
956 						&laarr[curr].extLocation,
957 						0, offset);
958 				laarr[curr].extLength =
959 					EXT_NOT_RECORDED_NOT_ALLOCATED |
960 					(offset << blocksize_bits);
961 				laarr[curr].extLocation.logicalBlockNum = 0;
962 				laarr[curr].extLocation.
963 						partitionReferenceNum = 0;
964 			} else
965 				laarr[curr].extLength = (etype << 30) |
966 					(offset << blocksize_bits);
967 			curr++;
968 			(*c)++;
969 			(*endnum)++;
970 		}
971 
972 		laarr[curr].extLocation.logicalBlockNum = newblocknum;
973 		if (etype == (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
974 			laarr[curr].extLocation.partitionReferenceNum =
975 				UDF_I(inode)->i_location.partitionReferenceNum;
976 		laarr[curr].extLength = EXT_RECORDED_ALLOCATED |
977 			blocksize;
978 		curr++;
979 
980 		if (blen != offset + 1) {
981 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
982 				laarr[curr].extLocation.logicalBlockNum +=
983 								offset + 1;
984 			laarr[curr].extLength = (etype << 30) |
985 				((blen - (offset + 1)) << blocksize_bits);
986 			curr++;
987 			(*endnum)++;
988 		}
989 	}
990 }
991 
992 static void udf_prealloc_extents(struct inode *inode, int c, int lastblock,
993 				 struct kernel_long_ad *laarr,
994 				 int *endnum)
995 {
996 	int start, length = 0, currlength = 0, i;
997 
998 	if (*endnum >= (c + 1)) {
999 		if (!lastblock)
1000 			return;
1001 		else
1002 			start = c;
1003 	} else {
1004 		if ((laarr[c + 1].extLength >> 30) ==
1005 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
1006 			start = c + 1;
1007 			length = currlength =
1008 				(((laarr[c + 1].extLength &
1009 					UDF_EXTENT_LENGTH_MASK) +
1010 				inode->i_sb->s_blocksize - 1) >>
1011 				inode->i_sb->s_blocksize_bits);
1012 		} else
1013 			start = c;
1014 	}
1015 
1016 	for (i = start + 1; i <= *endnum; i++) {
1017 		if (i == *endnum) {
1018 			if (lastblock)
1019 				length += UDF_DEFAULT_PREALLOC_BLOCKS;
1020 		} else if ((laarr[i].extLength >> 30) ==
1021 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
1022 			length += (((laarr[i].extLength &
1023 						UDF_EXTENT_LENGTH_MASK) +
1024 				    inode->i_sb->s_blocksize - 1) >>
1025 				    inode->i_sb->s_blocksize_bits);
1026 		} else
1027 			break;
1028 	}
1029 
1030 	if (length) {
1031 		int next = laarr[start].extLocation.logicalBlockNum +
1032 			(((laarr[start].extLength & UDF_EXTENT_LENGTH_MASK) +
1033 			  inode->i_sb->s_blocksize - 1) >>
1034 			  inode->i_sb->s_blocksize_bits);
1035 		int numalloc = udf_prealloc_blocks(inode->i_sb, inode,
1036 				laarr[start].extLocation.partitionReferenceNum,
1037 				next, (UDF_DEFAULT_PREALLOC_BLOCKS > length ?
1038 				length : UDF_DEFAULT_PREALLOC_BLOCKS) -
1039 				currlength);
1040 		if (numalloc) 	{
1041 			if (start == (c + 1))
1042 				laarr[start].extLength +=
1043 					(numalloc <<
1044 					 inode->i_sb->s_blocksize_bits);
1045 			else {
1046 				memmove(&laarr[c + 2], &laarr[c + 1],
1047 					sizeof(struct long_ad) * (*endnum - (c + 1)));
1048 				(*endnum)++;
1049 				laarr[c + 1].extLocation.logicalBlockNum = next;
1050 				laarr[c + 1].extLocation.partitionReferenceNum =
1051 					laarr[c].extLocation.
1052 							partitionReferenceNum;
1053 				laarr[c + 1].extLength =
1054 					EXT_NOT_RECORDED_ALLOCATED |
1055 					(numalloc <<
1056 					 inode->i_sb->s_blocksize_bits);
1057 				start = c + 1;
1058 			}
1059 
1060 			for (i = start + 1; numalloc && i < *endnum; i++) {
1061 				int elen = ((laarr[i].extLength &
1062 						UDF_EXTENT_LENGTH_MASK) +
1063 					    inode->i_sb->s_blocksize - 1) >>
1064 					    inode->i_sb->s_blocksize_bits;
1065 
1066 				if (elen > numalloc) {
1067 					laarr[i].extLength -=
1068 						(numalloc <<
1069 						 inode->i_sb->s_blocksize_bits);
1070 					numalloc = 0;
1071 				} else {
1072 					numalloc -= elen;
1073 					if (*endnum > (i + 1))
1074 						memmove(&laarr[i],
1075 							&laarr[i + 1],
1076 							sizeof(struct long_ad) *
1077 							(*endnum - (i + 1)));
1078 					i--;
1079 					(*endnum)--;
1080 				}
1081 			}
1082 			UDF_I(inode)->i_lenExtents +=
1083 				numalloc << inode->i_sb->s_blocksize_bits;
1084 		}
1085 	}
1086 }
1087 
1088 static void udf_merge_extents(struct inode *inode, struct kernel_long_ad *laarr,
1089 			      int *endnum)
1090 {
1091 	int i;
1092 	unsigned long blocksize = inode->i_sb->s_blocksize;
1093 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1094 
1095 	for (i = 0; i < (*endnum - 1); i++) {
1096 		struct kernel_long_ad *li /*l[i]*/ = &laarr[i];
1097 		struct kernel_long_ad *lip1 /*l[i plus 1]*/ = &laarr[i + 1];
1098 
1099 		if (((li->extLength >> 30) == (lip1->extLength >> 30)) &&
1100 			(((li->extLength >> 30) ==
1101 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) ||
1102 			((lip1->extLocation.logicalBlockNum -
1103 			  li->extLocation.logicalBlockNum) ==
1104 			(((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1105 			blocksize - 1) >> blocksize_bits)))) {
1106 
1107 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1108 			     (lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1109 			     blocksize - 1) <= UDF_EXTENT_LENGTH_MASK) {
1110 				li->extLength = lip1->extLength +
1111 					(((li->extLength &
1112 						UDF_EXTENT_LENGTH_MASK) +
1113 					 blocksize - 1) & ~(blocksize - 1));
1114 				if (*endnum > (i + 2))
1115 					memmove(&laarr[i + 1], &laarr[i + 2],
1116 						sizeof(struct long_ad) *
1117 						(*endnum - (i + 2)));
1118 				i--;
1119 				(*endnum)--;
1120 			}
1121 		} else if (((li->extLength >> 30) ==
1122 				(EXT_NOT_RECORDED_ALLOCATED >> 30)) &&
1123 			   ((lip1->extLength >> 30) ==
1124 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))) {
1125 			udf_free_blocks(inode->i_sb, inode, &li->extLocation, 0,
1126 					((li->extLength &
1127 					  UDF_EXTENT_LENGTH_MASK) +
1128 					 blocksize - 1) >> blocksize_bits);
1129 			li->extLocation.logicalBlockNum = 0;
1130 			li->extLocation.partitionReferenceNum = 0;
1131 
1132 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1133 			     (lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1134 			     blocksize - 1) & ~UDF_EXTENT_LENGTH_MASK) {
1135 				lip1->extLength = (lip1->extLength -
1136 						   (li->extLength &
1137 						   UDF_EXTENT_LENGTH_MASK) +
1138 						   UDF_EXTENT_LENGTH_MASK) &
1139 						   ~(blocksize - 1);
1140 				li->extLength = (li->extLength &
1141 						 UDF_EXTENT_FLAG_MASK) +
1142 						(UDF_EXTENT_LENGTH_MASK + 1) -
1143 						blocksize;
1144 			} else {
1145 				li->extLength = lip1->extLength +
1146 					(((li->extLength &
1147 						UDF_EXTENT_LENGTH_MASK) +
1148 					  blocksize - 1) & ~(blocksize - 1));
1149 				if (*endnum > (i + 2))
1150 					memmove(&laarr[i + 1], &laarr[i + 2],
1151 						sizeof(struct long_ad) *
1152 						(*endnum - (i + 2)));
1153 				i--;
1154 				(*endnum)--;
1155 			}
1156 		} else if ((li->extLength >> 30) ==
1157 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
1158 			udf_free_blocks(inode->i_sb, inode,
1159 					&li->extLocation, 0,
1160 					((li->extLength &
1161 						UDF_EXTENT_LENGTH_MASK) +
1162 					 blocksize - 1) >> blocksize_bits);
1163 			li->extLocation.logicalBlockNum = 0;
1164 			li->extLocation.partitionReferenceNum = 0;
1165 			li->extLength = (li->extLength &
1166 						UDF_EXTENT_LENGTH_MASK) |
1167 						EXT_NOT_RECORDED_NOT_ALLOCATED;
1168 		}
1169 	}
1170 }
1171 
1172 static int udf_update_extents(struct inode *inode, struct kernel_long_ad *laarr,
1173 			      int startnum, int endnum,
1174 			      struct extent_position *epos)
1175 {
1176 	int start = 0, i;
1177 	struct kernel_lb_addr tmploc;
1178 	uint32_t tmplen;
1179 	int err;
1180 
1181 	if (startnum > endnum) {
1182 		for (i = 0; i < (startnum - endnum); i++)
1183 			udf_delete_aext(inode, *epos);
1184 	} else if (startnum < endnum) {
1185 		for (i = 0; i < (endnum - startnum); i++) {
1186 			err = udf_insert_aext(inode, *epos,
1187 					      laarr[i].extLocation,
1188 					      laarr[i].extLength);
1189 			/*
1190 			 * If we fail here, we are likely corrupting the extent
1191 			 * list and leaking blocks. At least stop early to
1192 			 * limit the damage.
1193 			 */
1194 			if (err < 0)
1195 				return err;
1196 			udf_next_aext(inode, epos, &laarr[i].extLocation,
1197 				      &laarr[i].extLength, 1);
1198 			start++;
1199 		}
1200 	}
1201 
1202 	for (i = start; i < endnum; i++) {
1203 		udf_next_aext(inode, epos, &tmploc, &tmplen, 0);
1204 		udf_write_aext(inode, epos, &laarr[i].extLocation,
1205 			       laarr[i].extLength, 1);
1206 	}
1207 	return 0;
1208 }
1209 
1210 struct buffer_head *udf_bread(struct inode *inode, udf_pblk_t block,
1211 			      int create, int *err)
1212 {
1213 	struct buffer_head *bh = NULL;
1214 	struct udf_map_rq map = {
1215 		.lblk = block,
1216 		.iflags = UDF_MAP_NOPREALLOC | (create ? UDF_MAP_CREATE : 0),
1217 	};
1218 
1219 	*err = udf_map_block(inode, &map);
1220 	if (*err || !(map.oflags & UDF_BLK_MAPPED))
1221 		return NULL;
1222 
1223 	bh = sb_getblk(inode->i_sb, map.pblk);
1224 	if (!bh) {
1225 		*err = -ENOMEM;
1226 		return NULL;
1227 	}
1228 	if (map.oflags & UDF_BLK_NEW) {
1229 		lock_buffer(bh);
1230 		memset(bh->b_data, 0x00, inode->i_sb->s_blocksize);
1231 		set_buffer_uptodate(bh);
1232 		unlock_buffer(bh);
1233 		mark_buffer_dirty_inode(bh, inode);
1234 		return bh;
1235 	}
1236 
1237 	if (bh_read(bh, 0) >= 0)
1238 		return bh;
1239 
1240 	brelse(bh);
1241 	*err = -EIO;
1242 	return NULL;
1243 }
1244 
1245 int udf_setsize(struct inode *inode, loff_t newsize)
1246 {
1247 	int err = 0;
1248 	struct udf_inode_info *iinfo;
1249 	unsigned int bsize = i_blocksize(inode);
1250 
1251 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1252 	      S_ISLNK(inode->i_mode)))
1253 		return -EINVAL;
1254 	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
1255 		return -EPERM;
1256 
1257 	filemap_invalidate_lock(inode->i_mapping);
1258 	iinfo = UDF_I(inode);
1259 	if (newsize > inode->i_size) {
1260 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1261 			if (bsize >=
1262 			    (udf_file_entry_alloc_offset(inode) + newsize)) {
1263 				down_write(&iinfo->i_data_sem);
1264 				iinfo->i_lenAlloc = newsize;
1265 				up_write(&iinfo->i_data_sem);
1266 				goto set_size;
1267 			}
1268 			err = udf_expand_file_adinicb(inode);
1269 			if (err)
1270 				goto out_unlock;
1271 		}
1272 		err = udf_extend_file(inode, newsize);
1273 		if (err)
1274 			goto out_unlock;
1275 set_size:
1276 		truncate_setsize(inode, newsize);
1277 	} else {
1278 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1279 			down_write(&iinfo->i_data_sem);
1280 			udf_clear_extent_cache(inode);
1281 			memset(iinfo->i_data + iinfo->i_lenEAttr + newsize,
1282 			       0x00, bsize - newsize -
1283 			       udf_file_entry_alloc_offset(inode));
1284 			iinfo->i_lenAlloc = newsize;
1285 			truncate_setsize(inode, newsize);
1286 			up_write(&iinfo->i_data_sem);
1287 			goto update_time;
1288 		}
1289 		err = block_truncate_page(inode->i_mapping, newsize,
1290 					  udf_get_block);
1291 		if (err)
1292 			goto out_unlock;
1293 		truncate_setsize(inode, newsize);
1294 		down_write(&iinfo->i_data_sem);
1295 		udf_clear_extent_cache(inode);
1296 		err = udf_truncate_extents(inode);
1297 		up_write(&iinfo->i_data_sem);
1298 		if (err)
1299 			goto out_unlock;
1300 	}
1301 update_time:
1302 	inode->i_mtime = inode->i_ctime = current_time(inode);
1303 	if (IS_SYNC(inode))
1304 		udf_sync_inode(inode);
1305 	else
1306 		mark_inode_dirty(inode);
1307 out_unlock:
1308 	filemap_invalidate_unlock(inode->i_mapping);
1309 	return err;
1310 }
1311 
1312 /*
1313  * Maximum length of linked list formed by ICB hierarchy. The chosen number is
1314  * arbitrary - just that we hopefully don't limit any real use of rewritten
1315  * inode on write-once media but avoid looping for too long on corrupted media.
1316  */
1317 #define UDF_MAX_ICB_NESTING 1024
1318 
1319 static int udf_read_inode(struct inode *inode, bool hidden_inode)
1320 {
1321 	struct buffer_head *bh = NULL;
1322 	struct fileEntry *fe;
1323 	struct extendedFileEntry *efe;
1324 	uint16_t ident;
1325 	struct udf_inode_info *iinfo = UDF_I(inode);
1326 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1327 	struct kernel_lb_addr *iloc = &iinfo->i_location;
1328 	unsigned int link_count;
1329 	unsigned int indirections = 0;
1330 	int bs = inode->i_sb->s_blocksize;
1331 	int ret = -EIO;
1332 	uint32_t uid, gid;
1333 
1334 reread:
1335 	if (iloc->partitionReferenceNum >= sbi->s_partitions) {
1336 		udf_debug("partition reference: %u > logical volume partitions: %u\n",
1337 			  iloc->partitionReferenceNum, sbi->s_partitions);
1338 		return -EIO;
1339 	}
1340 
1341 	if (iloc->logicalBlockNum >=
1342 	    sbi->s_partmaps[iloc->partitionReferenceNum].s_partition_len) {
1343 		udf_debug("block=%u, partition=%u out of range\n",
1344 			  iloc->logicalBlockNum, iloc->partitionReferenceNum);
1345 		return -EIO;
1346 	}
1347 
1348 	/*
1349 	 * Set defaults, but the inode is still incomplete!
1350 	 * Note: get_new_inode() sets the following on a new inode:
1351 	 *      i_sb = sb
1352 	 *      i_no = ino
1353 	 *      i_flags = sb->s_flags
1354 	 *      i_state = 0
1355 	 * clean_inode(): zero fills and sets
1356 	 *      i_count = 1
1357 	 *      i_nlink = 1
1358 	 *      i_op = NULL;
1359 	 */
1360 	bh = udf_read_ptagged(inode->i_sb, iloc, 0, &ident);
1361 	if (!bh) {
1362 		udf_err(inode->i_sb, "(ino %lu) failed !bh\n", inode->i_ino);
1363 		return -EIO;
1364 	}
1365 
1366 	if (ident != TAG_IDENT_FE && ident != TAG_IDENT_EFE &&
1367 	    ident != TAG_IDENT_USE) {
1368 		udf_err(inode->i_sb, "(ino %lu) failed ident=%u\n",
1369 			inode->i_ino, ident);
1370 		goto out;
1371 	}
1372 
1373 	fe = (struct fileEntry *)bh->b_data;
1374 	efe = (struct extendedFileEntry *)bh->b_data;
1375 
1376 	if (fe->icbTag.strategyType == cpu_to_le16(4096)) {
1377 		struct buffer_head *ibh;
1378 
1379 		ibh = udf_read_ptagged(inode->i_sb, iloc, 1, &ident);
1380 		if (ident == TAG_IDENT_IE && ibh) {
1381 			struct kernel_lb_addr loc;
1382 			struct indirectEntry *ie;
1383 
1384 			ie = (struct indirectEntry *)ibh->b_data;
1385 			loc = lelb_to_cpu(ie->indirectICB.extLocation);
1386 
1387 			if (ie->indirectICB.extLength) {
1388 				brelse(ibh);
1389 				memcpy(&iinfo->i_location, &loc,
1390 				       sizeof(struct kernel_lb_addr));
1391 				if (++indirections > UDF_MAX_ICB_NESTING) {
1392 					udf_err(inode->i_sb,
1393 						"too many ICBs in ICB hierarchy"
1394 						" (max %d supported)\n",
1395 						UDF_MAX_ICB_NESTING);
1396 					goto out;
1397 				}
1398 				brelse(bh);
1399 				goto reread;
1400 			}
1401 		}
1402 		brelse(ibh);
1403 	} else if (fe->icbTag.strategyType != cpu_to_le16(4)) {
1404 		udf_err(inode->i_sb, "unsupported strategy type: %u\n",
1405 			le16_to_cpu(fe->icbTag.strategyType));
1406 		goto out;
1407 	}
1408 	if (fe->icbTag.strategyType == cpu_to_le16(4))
1409 		iinfo->i_strat4096 = 0;
1410 	else /* if (fe->icbTag.strategyType == cpu_to_le16(4096)) */
1411 		iinfo->i_strat4096 = 1;
1412 
1413 	iinfo->i_alloc_type = le16_to_cpu(fe->icbTag.flags) &
1414 							ICBTAG_FLAG_AD_MASK;
1415 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_SHORT &&
1416 	    iinfo->i_alloc_type != ICBTAG_FLAG_AD_LONG &&
1417 	    iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
1418 		ret = -EIO;
1419 		goto out;
1420 	}
1421 	iinfo->i_hidden = hidden_inode;
1422 	iinfo->i_unique = 0;
1423 	iinfo->i_lenEAttr = 0;
1424 	iinfo->i_lenExtents = 0;
1425 	iinfo->i_lenAlloc = 0;
1426 	iinfo->i_next_alloc_block = 0;
1427 	iinfo->i_next_alloc_goal = 0;
1428 	if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_EFE)) {
1429 		iinfo->i_efe = 1;
1430 		iinfo->i_use = 0;
1431 		ret = udf_alloc_i_data(inode, bs -
1432 					sizeof(struct extendedFileEntry));
1433 		if (ret)
1434 			goto out;
1435 		memcpy(iinfo->i_data,
1436 		       bh->b_data + sizeof(struct extendedFileEntry),
1437 		       bs - sizeof(struct extendedFileEntry));
1438 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_FE)) {
1439 		iinfo->i_efe = 0;
1440 		iinfo->i_use = 0;
1441 		ret = udf_alloc_i_data(inode, bs - sizeof(struct fileEntry));
1442 		if (ret)
1443 			goto out;
1444 		memcpy(iinfo->i_data,
1445 		       bh->b_data + sizeof(struct fileEntry),
1446 		       bs - sizeof(struct fileEntry));
1447 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_USE)) {
1448 		iinfo->i_efe = 0;
1449 		iinfo->i_use = 1;
1450 		iinfo->i_lenAlloc = le32_to_cpu(
1451 				((struct unallocSpaceEntry *)bh->b_data)->
1452 				 lengthAllocDescs);
1453 		ret = udf_alloc_i_data(inode, bs -
1454 					sizeof(struct unallocSpaceEntry));
1455 		if (ret)
1456 			goto out;
1457 		memcpy(iinfo->i_data,
1458 		       bh->b_data + sizeof(struct unallocSpaceEntry),
1459 		       bs - sizeof(struct unallocSpaceEntry));
1460 		return 0;
1461 	}
1462 
1463 	ret = -EIO;
1464 	read_lock(&sbi->s_cred_lock);
1465 	uid = le32_to_cpu(fe->uid);
1466 	if (uid == UDF_INVALID_ID ||
1467 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_SET))
1468 		inode->i_uid = sbi->s_uid;
1469 	else
1470 		i_uid_write(inode, uid);
1471 
1472 	gid = le32_to_cpu(fe->gid);
1473 	if (gid == UDF_INVALID_ID ||
1474 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_SET))
1475 		inode->i_gid = sbi->s_gid;
1476 	else
1477 		i_gid_write(inode, gid);
1478 
1479 	if (fe->icbTag.fileType != ICBTAG_FILE_TYPE_DIRECTORY &&
1480 			sbi->s_fmode != UDF_INVALID_MODE)
1481 		inode->i_mode = sbi->s_fmode;
1482 	else if (fe->icbTag.fileType == ICBTAG_FILE_TYPE_DIRECTORY &&
1483 			sbi->s_dmode != UDF_INVALID_MODE)
1484 		inode->i_mode = sbi->s_dmode;
1485 	else
1486 		inode->i_mode = udf_convert_permissions(fe);
1487 	inode->i_mode &= ~sbi->s_umask;
1488 	iinfo->i_extraPerms = le32_to_cpu(fe->permissions) & ~FE_MAPPED_PERMS;
1489 
1490 	read_unlock(&sbi->s_cred_lock);
1491 
1492 	link_count = le16_to_cpu(fe->fileLinkCount);
1493 	if (!link_count) {
1494 		if (!hidden_inode) {
1495 			ret = -ESTALE;
1496 			goto out;
1497 		}
1498 		link_count = 1;
1499 	}
1500 	set_nlink(inode, link_count);
1501 
1502 	inode->i_size = le64_to_cpu(fe->informationLength);
1503 	iinfo->i_lenExtents = inode->i_size;
1504 
1505 	if (iinfo->i_efe == 0) {
1506 		inode->i_blocks = le64_to_cpu(fe->logicalBlocksRecorded) <<
1507 			(inode->i_sb->s_blocksize_bits - 9);
1508 
1509 		udf_disk_stamp_to_time(&inode->i_atime, fe->accessTime);
1510 		udf_disk_stamp_to_time(&inode->i_mtime, fe->modificationTime);
1511 		udf_disk_stamp_to_time(&inode->i_ctime, fe->attrTime);
1512 
1513 		iinfo->i_unique = le64_to_cpu(fe->uniqueID);
1514 		iinfo->i_lenEAttr = le32_to_cpu(fe->lengthExtendedAttr);
1515 		iinfo->i_lenAlloc = le32_to_cpu(fe->lengthAllocDescs);
1516 		iinfo->i_checkpoint = le32_to_cpu(fe->checkpoint);
1517 		iinfo->i_streamdir = 0;
1518 		iinfo->i_lenStreams = 0;
1519 	} else {
1520 		inode->i_blocks = le64_to_cpu(efe->logicalBlocksRecorded) <<
1521 		    (inode->i_sb->s_blocksize_bits - 9);
1522 
1523 		udf_disk_stamp_to_time(&inode->i_atime, efe->accessTime);
1524 		udf_disk_stamp_to_time(&inode->i_mtime, efe->modificationTime);
1525 		udf_disk_stamp_to_time(&iinfo->i_crtime, efe->createTime);
1526 		udf_disk_stamp_to_time(&inode->i_ctime, efe->attrTime);
1527 
1528 		iinfo->i_unique = le64_to_cpu(efe->uniqueID);
1529 		iinfo->i_lenEAttr = le32_to_cpu(efe->lengthExtendedAttr);
1530 		iinfo->i_lenAlloc = le32_to_cpu(efe->lengthAllocDescs);
1531 		iinfo->i_checkpoint = le32_to_cpu(efe->checkpoint);
1532 
1533 		/* Named streams */
1534 		iinfo->i_streamdir = (efe->streamDirectoryICB.extLength != 0);
1535 		iinfo->i_locStreamdir =
1536 			lelb_to_cpu(efe->streamDirectoryICB.extLocation);
1537 		iinfo->i_lenStreams = le64_to_cpu(efe->objectSize);
1538 		if (iinfo->i_lenStreams >= inode->i_size)
1539 			iinfo->i_lenStreams -= inode->i_size;
1540 		else
1541 			iinfo->i_lenStreams = 0;
1542 	}
1543 	inode->i_generation = iinfo->i_unique;
1544 
1545 	/*
1546 	 * Sanity check length of allocation descriptors and extended attrs to
1547 	 * avoid integer overflows
1548 	 */
1549 	if (iinfo->i_lenEAttr > bs || iinfo->i_lenAlloc > bs)
1550 		goto out;
1551 	/* Now do exact checks */
1552 	if (udf_file_entry_alloc_offset(inode) + iinfo->i_lenAlloc > bs)
1553 		goto out;
1554 	/* Sanity checks for files in ICB so that we don't get confused later */
1555 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1556 		/*
1557 		 * For file in ICB data is stored in allocation descriptor
1558 		 * so sizes should match
1559 		 */
1560 		if (iinfo->i_lenAlloc != inode->i_size)
1561 			goto out;
1562 		/* File in ICB has to fit in there... */
1563 		if (inode->i_size > bs - udf_file_entry_alloc_offset(inode))
1564 			goto out;
1565 	}
1566 
1567 	switch (fe->icbTag.fileType) {
1568 	case ICBTAG_FILE_TYPE_DIRECTORY:
1569 		inode->i_op = &udf_dir_inode_operations;
1570 		inode->i_fop = &udf_dir_operations;
1571 		inode->i_mode |= S_IFDIR;
1572 		inc_nlink(inode);
1573 		break;
1574 	case ICBTAG_FILE_TYPE_REALTIME:
1575 	case ICBTAG_FILE_TYPE_REGULAR:
1576 	case ICBTAG_FILE_TYPE_UNDEF:
1577 	case ICBTAG_FILE_TYPE_VAT20:
1578 		inode->i_data.a_ops = &udf_aops;
1579 		inode->i_op = &udf_file_inode_operations;
1580 		inode->i_fop = &udf_file_operations;
1581 		inode->i_mode |= S_IFREG;
1582 		break;
1583 	case ICBTAG_FILE_TYPE_BLOCK:
1584 		inode->i_mode |= S_IFBLK;
1585 		break;
1586 	case ICBTAG_FILE_TYPE_CHAR:
1587 		inode->i_mode |= S_IFCHR;
1588 		break;
1589 	case ICBTAG_FILE_TYPE_FIFO:
1590 		init_special_inode(inode, inode->i_mode | S_IFIFO, 0);
1591 		break;
1592 	case ICBTAG_FILE_TYPE_SOCKET:
1593 		init_special_inode(inode, inode->i_mode | S_IFSOCK, 0);
1594 		break;
1595 	case ICBTAG_FILE_TYPE_SYMLINK:
1596 		inode->i_data.a_ops = &udf_symlink_aops;
1597 		inode->i_op = &udf_symlink_inode_operations;
1598 		inode_nohighmem(inode);
1599 		inode->i_mode = S_IFLNK | 0777;
1600 		break;
1601 	case ICBTAG_FILE_TYPE_MAIN:
1602 		udf_debug("METADATA FILE-----\n");
1603 		break;
1604 	case ICBTAG_FILE_TYPE_MIRROR:
1605 		udf_debug("METADATA MIRROR FILE-----\n");
1606 		break;
1607 	case ICBTAG_FILE_TYPE_BITMAP:
1608 		udf_debug("METADATA BITMAP FILE-----\n");
1609 		break;
1610 	default:
1611 		udf_err(inode->i_sb, "(ino %lu) failed unknown file type=%u\n",
1612 			inode->i_ino, fe->icbTag.fileType);
1613 		goto out;
1614 	}
1615 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1616 		struct deviceSpec *dsea =
1617 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1618 		if (dsea) {
1619 			init_special_inode(inode, inode->i_mode,
1620 				MKDEV(le32_to_cpu(dsea->majorDeviceIdent),
1621 				      le32_to_cpu(dsea->minorDeviceIdent)));
1622 			/* Developer ID ??? */
1623 		} else
1624 			goto out;
1625 	}
1626 	ret = 0;
1627 out:
1628 	brelse(bh);
1629 	return ret;
1630 }
1631 
1632 static int udf_alloc_i_data(struct inode *inode, size_t size)
1633 {
1634 	struct udf_inode_info *iinfo = UDF_I(inode);
1635 	iinfo->i_data = kmalloc(size, GFP_KERNEL);
1636 	if (!iinfo->i_data)
1637 		return -ENOMEM;
1638 	return 0;
1639 }
1640 
1641 static umode_t udf_convert_permissions(struct fileEntry *fe)
1642 {
1643 	umode_t mode;
1644 	uint32_t permissions;
1645 	uint32_t flags;
1646 
1647 	permissions = le32_to_cpu(fe->permissions);
1648 	flags = le16_to_cpu(fe->icbTag.flags);
1649 
1650 	mode =	((permissions) & 0007) |
1651 		((permissions >> 2) & 0070) |
1652 		((permissions >> 4) & 0700) |
1653 		((flags & ICBTAG_FLAG_SETUID) ? S_ISUID : 0) |
1654 		((flags & ICBTAG_FLAG_SETGID) ? S_ISGID : 0) |
1655 		((flags & ICBTAG_FLAG_STICKY) ? S_ISVTX : 0);
1656 
1657 	return mode;
1658 }
1659 
1660 void udf_update_extra_perms(struct inode *inode, umode_t mode)
1661 {
1662 	struct udf_inode_info *iinfo = UDF_I(inode);
1663 
1664 	/*
1665 	 * UDF 2.01 sec. 3.3.3.3 Note 2:
1666 	 * In Unix, delete permission tracks write
1667 	 */
1668 	iinfo->i_extraPerms &= ~FE_DELETE_PERMS;
1669 	if (mode & 0200)
1670 		iinfo->i_extraPerms |= FE_PERM_U_DELETE;
1671 	if (mode & 0020)
1672 		iinfo->i_extraPerms |= FE_PERM_G_DELETE;
1673 	if (mode & 0002)
1674 		iinfo->i_extraPerms |= FE_PERM_O_DELETE;
1675 }
1676 
1677 int udf_write_inode(struct inode *inode, struct writeback_control *wbc)
1678 {
1679 	return udf_update_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
1680 }
1681 
1682 static int udf_sync_inode(struct inode *inode)
1683 {
1684 	return udf_update_inode(inode, 1);
1685 }
1686 
1687 static void udf_adjust_time(struct udf_inode_info *iinfo, struct timespec64 time)
1688 {
1689 	if (iinfo->i_crtime.tv_sec > time.tv_sec ||
1690 	    (iinfo->i_crtime.tv_sec == time.tv_sec &&
1691 	     iinfo->i_crtime.tv_nsec > time.tv_nsec))
1692 		iinfo->i_crtime = time;
1693 }
1694 
1695 static int udf_update_inode(struct inode *inode, int do_sync)
1696 {
1697 	struct buffer_head *bh = NULL;
1698 	struct fileEntry *fe;
1699 	struct extendedFileEntry *efe;
1700 	uint64_t lb_recorded;
1701 	uint32_t udfperms;
1702 	uint16_t icbflags;
1703 	uint16_t crclen;
1704 	int err = 0;
1705 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1706 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1707 	struct udf_inode_info *iinfo = UDF_I(inode);
1708 
1709 	bh = sb_getblk(inode->i_sb,
1710 			udf_get_lb_pblock(inode->i_sb, &iinfo->i_location, 0));
1711 	if (!bh) {
1712 		udf_debug("getblk failure\n");
1713 		return -EIO;
1714 	}
1715 
1716 	lock_buffer(bh);
1717 	memset(bh->b_data, 0, inode->i_sb->s_blocksize);
1718 	fe = (struct fileEntry *)bh->b_data;
1719 	efe = (struct extendedFileEntry *)bh->b_data;
1720 
1721 	if (iinfo->i_use) {
1722 		struct unallocSpaceEntry *use =
1723 			(struct unallocSpaceEntry *)bh->b_data;
1724 
1725 		use->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1726 		memcpy(bh->b_data + sizeof(struct unallocSpaceEntry),
1727 		       iinfo->i_data, inode->i_sb->s_blocksize -
1728 					sizeof(struct unallocSpaceEntry));
1729 		use->descTag.tagIdent = cpu_to_le16(TAG_IDENT_USE);
1730 		crclen = sizeof(struct unallocSpaceEntry);
1731 
1732 		goto finish;
1733 	}
1734 
1735 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_FORGET))
1736 		fe->uid = cpu_to_le32(UDF_INVALID_ID);
1737 	else
1738 		fe->uid = cpu_to_le32(i_uid_read(inode));
1739 
1740 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_FORGET))
1741 		fe->gid = cpu_to_le32(UDF_INVALID_ID);
1742 	else
1743 		fe->gid = cpu_to_le32(i_gid_read(inode));
1744 
1745 	udfperms = ((inode->i_mode & 0007)) |
1746 		   ((inode->i_mode & 0070) << 2) |
1747 		   ((inode->i_mode & 0700) << 4);
1748 
1749 	udfperms |= iinfo->i_extraPerms;
1750 	fe->permissions = cpu_to_le32(udfperms);
1751 
1752 	if (S_ISDIR(inode->i_mode) && inode->i_nlink > 0)
1753 		fe->fileLinkCount = cpu_to_le16(inode->i_nlink - 1);
1754 	else {
1755 		if (iinfo->i_hidden)
1756 			fe->fileLinkCount = cpu_to_le16(0);
1757 		else
1758 			fe->fileLinkCount = cpu_to_le16(inode->i_nlink);
1759 	}
1760 
1761 	fe->informationLength = cpu_to_le64(inode->i_size);
1762 
1763 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1764 		struct regid *eid;
1765 		struct deviceSpec *dsea =
1766 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1767 		if (!dsea) {
1768 			dsea = (struct deviceSpec *)
1769 				udf_add_extendedattr(inode,
1770 						     sizeof(struct deviceSpec) +
1771 						     sizeof(struct regid), 12, 0x3);
1772 			dsea->attrType = cpu_to_le32(12);
1773 			dsea->attrSubtype = 1;
1774 			dsea->attrLength = cpu_to_le32(
1775 						sizeof(struct deviceSpec) +
1776 						sizeof(struct regid));
1777 			dsea->impUseLength = cpu_to_le32(sizeof(struct regid));
1778 		}
1779 		eid = (struct regid *)dsea->impUse;
1780 		memset(eid, 0, sizeof(*eid));
1781 		strcpy(eid->ident, UDF_ID_DEVELOPER);
1782 		eid->identSuffix[0] = UDF_OS_CLASS_UNIX;
1783 		eid->identSuffix[1] = UDF_OS_ID_LINUX;
1784 		dsea->majorDeviceIdent = cpu_to_le32(imajor(inode));
1785 		dsea->minorDeviceIdent = cpu_to_le32(iminor(inode));
1786 	}
1787 
1788 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1789 		lb_recorded = 0; /* No extents => no blocks! */
1790 	else
1791 		lb_recorded =
1792 			(inode->i_blocks + (1 << (blocksize_bits - 9)) - 1) >>
1793 			(blocksize_bits - 9);
1794 
1795 	if (iinfo->i_efe == 0) {
1796 		memcpy(bh->b_data + sizeof(struct fileEntry),
1797 		       iinfo->i_data,
1798 		       inode->i_sb->s_blocksize - sizeof(struct fileEntry));
1799 		fe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
1800 
1801 		udf_time_to_disk_stamp(&fe->accessTime, inode->i_atime);
1802 		udf_time_to_disk_stamp(&fe->modificationTime, inode->i_mtime);
1803 		udf_time_to_disk_stamp(&fe->attrTime, inode->i_ctime);
1804 		memset(&(fe->impIdent), 0, sizeof(struct regid));
1805 		strcpy(fe->impIdent.ident, UDF_ID_DEVELOPER);
1806 		fe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1807 		fe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1808 		fe->uniqueID = cpu_to_le64(iinfo->i_unique);
1809 		fe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
1810 		fe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1811 		fe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
1812 		fe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_FE);
1813 		crclen = sizeof(struct fileEntry);
1814 	} else {
1815 		memcpy(bh->b_data + sizeof(struct extendedFileEntry),
1816 		       iinfo->i_data,
1817 		       inode->i_sb->s_blocksize -
1818 					sizeof(struct extendedFileEntry));
1819 		efe->objectSize =
1820 			cpu_to_le64(inode->i_size + iinfo->i_lenStreams);
1821 		efe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
1822 
1823 		if (iinfo->i_streamdir) {
1824 			struct long_ad *icb_lad = &efe->streamDirectoryICB;
1825 
1826 			icb_lad->extLocation =
1827 				cpu_to_lelb(iinfo->i_locStreamdir);
1828 			icb_lad->extLength =
1829 				cpu_to_le32(inode->i_sb->s_blocksize);
1830 		}
1831 
1832 		udf_adjust_time(iinfo, inode->i_atime);
1833 		udf_adjust_time(iinfo, inode->i_mtime);
1834 		udf_adjust_time(iinfo, inode->i_ctime);
1835 
1836 		udf_time_to_disk_stamp(&efe->accessTime, inode->i_atime);
1837 		udf_time_to_disk_stamp(&efe->modificationTime, inode->i_mtime);
1838 		udf_time_to_disk_stamp(&efe->createTime, iinfo->i_crtime);
1839 		udf_time_to_disk_stamp(&efe->attrTime, inode->i_ctime);
1840 
1841 		memset(&(efe->impIdent), 0, sizeof(efe->impIdent));
1842 		strcpy(efe->impIdent.ident, UDF_ID_DEVELOPER);
1843 		efe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1844 		efe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1845 		efe->uniqueID = cpu_to_le64(iinfo->i_unique);
1846 		efe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
1847 		efe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1848 		efe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
1849 		efe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EFE);
1850 		crclen = sizeof(struct extendedFileEntry);
1851 	}
1852 
1853 finish:
1854 	if (iinfo->i_strat4096) {
1855 		fe->icbTag.strategyType = cpu_to_le16(4096);
1856 		fe->icbTag.strategyParameter = cpu_to_le16(1);
1857 		fe->icbTag.numEntries = cpu_to_le16(2);
1858 	} else {
1859 		fe->icbTag.strategyType = cpu_to_le16(4);
1860 		fe->icbTag.numEntries = cpu_to_le16(1);
1861 	}
1862 
1863 	if (iinfo->i_use)
1864 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_USE;
1865 	else if (S_ISDIR(inode->i_mode))
1866 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_DIRECTORY;
1867 	else if (S_ISREG(inode->i_mode))
1868 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_REGULAR;
1869 	else if (S_ISLNK(inode->i_mode))
1870 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SYMLINK;
1871 	else if (S_ISBLK(inode->i_mode))
1872 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_BLOCK;
1873 	else if (S_ISCHR(inode->i_mode))
1874 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_CHAR;
1875 	else if (S_ISFIFO(inode->i_mode))
1876 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_FIFO;
1877 	else if (S_ISSOCK(inode->i_mode))
1878 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SOCKET;
1879 
1880 	icbflags =	iinfo->i_alloc_type |
1881 			((inode->i_mode & S_ISUID) ? ICBTAG_FLAG_SETUID : 0) |
1882 			((inode->i_mode & S_ISGID) ? ICBTAG_FLAG_SETGID : 0) |
1883 			((inode->i_mode & S_ISVTX) ? ICBTAG_FLAG_STICKY : 0) |
1884 			(le16_to_cpu(fe->icbTag.flags) &
1885 				~(ICBTAG_FLAG_AD_MASK | ICBTAG_FLAG_SETUID |
1886 				ICBTAG_FLAG_SETGID | ICBTAG_FLAG_STICKY));
1887 
1888 	fe->icbTag.flags = cpu_to_le16(icbflags);
1889 	if (sbi->s_udfrev >= 0x0200)
1890 		fe->descTag.descVersion = cpu_to_le16(3);
1891 	else
1892 		fe->descTag.descVersion = cpu_to_le16(2);
1893 	fe->descTag.tagSerialNum = cpu_to_le16(sbi->s_serial_number);
1894 	fe->descTag.tagLocation = cpu_to_le32(
1895 					iinfo->i_location.logicalBlockNum);
1896 	crclen += iinfo->i_lenEAttr + iinfo->i_lenAlloc - sizeof(struct tag);
1897 	fe->descTag.descCRCLength = cpu_to_le16(crclen);
1898 	fe->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)fe + sizeof(struct tag),
1899 						  crclen));
1900 	fe->descTag.tagChecksum = udf_tag_checksum(&fe->descTag);
1901 
1902 	set_buffer_uptodate(bh);
1903 	unlock_buffer(bh);
1904 
1905 	/* write the data blocks */
1906 	mark_buffer_dirty(bh);
1907 	if (do_sync) {
1908 		sync_dirty_buffer(bh);
1909 		if (buffer_write_io_error(bh)) {
1910 			udf_warn(inode->i_sb, "IO error syncing udf inode [%08lx]\n",
1911 				 inode->i_ino);
1912 			err = -EIO;
1913 		}
1914 	}
1915 	brelse(bh);
1916 
1917 	return err;
1918 }
1919 
1920 struct inode *__udf_iget(struct super_block *sb, struct kernel_lb_addr *ino,
1921 			 bool hidden_inode)
1922 {
1923 	unsigned long block = udf_get_lb_pblock(sb, ino, 0);
1924 	struct inode *inode = iget_locked(sb, block);
1925 	int err;
1926 
1927 	if (!inode)
1928 		return ERR_PTR(-ENOMEM);
1929 
1930 	if (!(inode->i_state & I_NEW)) {
1931 		if (UDF_I(inode)->i_hidden != hidden_inode) {
1932 			iput(inode);
1933 			return ERR_PTR(-EFSCORRUPTED);
1934 		}
1935 		return inode;
1936 	}
1937 
1938 	memcpy(&UDF_I(inode)->i_location, ino, sizeof(struct kernel_lb_addr));
1939 	err = udf_read_inode(inode, hidden_inode);
1940 	if (err < 0) {
1941 		iget_failed(inode);
1942 		return ERR_PTR(err);
1943 	}
1944 	unlock_new_inode(inode);
1945 
1946 	return inode;
1947 }
1948 
1949 int udf_setup_indirect_aext(struct inode *inode, udf_pblk_t block,
1950 			    struct extent_position *epos)
1951 {
1952 	struct super_block *sb = inode->i_sb;
1953 	struct buffer_head *bh;
1954 	struct allocExtDesc *aed;
1955 	struct extent_position nepos;
1956 	struct kernel_lb_addr neloc;
1957 	int ver, adsize;
1958 
1959 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
1960 		adsize = sizeof(struct short_ad);
1961 	else if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_LONG)
1962 		adsize = sizeof(struct long_ad);
1963 	else
1964 		return -EIO;
1965 
1966 	neloc.logicalBlockNum = block;
1967 	neloc.partitionReferenceNum = epos->block.partitionReferenceNum;
1968 
1969 	bh = sb_getblk(sb, udf_get_lb_pblock(sb, &neloc, 0));
1970 	if (!bh)
1971 		return -EIO;
1972 	lock_buffer(bh);
1973 	memset(bh->b_data, 0x00, sb->s_blocksize);
1974 	set_buffer_uptodate(bh);
1975 	unlock_buffer(bh);
1976 	mark_buffer_dirty_inode(bh, inode);
1977 
1978 	aed = (struct allocExtDesc *)(bh->b_data);
1979 	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT)) {
1980 		aed->previousAllocExtLocation =
1981 				cpu_to_le32(epos->block.logicalBlockNum);
1982 	}
1983 	aed->lengthAllocDescs = cpu_to_le32(0);
1984 	if (UDF_SB(sb)->s_udfrev >= 0x0200)
1985 		ver = 3;
1986 	else
1987 		ver = 2;
1988 	udf_new_tag(bh->b_data, TAG_IDENT_AED, ver, 1, block,
1989 		    sizeof(struct tag));
1990 
1991 	nepos.block = neloc;
1992 	nepos.offset = sizeof(struct allocExtDesc);
1993 	nepos.bh = bh;
1994 
1995 	/*
1996 	 * Do we have to copy current last extent to make space for indirect
1997 	 * one?
1998 	 */
1999 	if (epos->offset + adsize > sb->s_blocksize) {
2000 		struct kernel_lb_addr cp_loc;
2001 		uint32_t cp_len;
2002 		int cp_type;
2003 
2004 		epos->offset -= adsize;
2005 		cp_type = udf_current_aext(inode, epos, &cp_loc, &cp_len, 0);
2006 		cp_len |= ((uint32_t)cp_type) << 30;
2007 
2008 		__udf_add_aext(inode, &nepos, &cp_loc, cp_len, 1);
2009 		udf_write_aext(inode, epos, &nepos.block,
2010 			       sb->s_blocksize | EXT_NEXT_EXTENT_ALLOCDESCS, 0);
2011 	} else {
2012 		__udf_add_aext(inode, epos, &nepos.block,
2013 			       sb->s_blocksize | EXT_NEXT_EXTENT_ALLOCDESCS, 0);
2014 	}
2015 
2016 	brelse(epos->bh);
2017 	*epos = nepos;
2018 
2019 	return 0;
2020 }
2021 
2022 /*
2023  * Append extent at the given position - should be the first free one in inode
2024  * / indirect extent. This function assumes there is enough space in the inode
2025  * or indirect extent. Use udf_add_aext() if you didn't check for this before.
2026  */
2027 int __udf_add_aext(struct inode *inode, struct extent_position *epos,
2028 		   struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2029 {
2030 	struct udf_inode_info *iinfo = UDF_I(inode);
2031 	struct allocExtDesc *aed;
2032 	int adsize;
2033 
2034 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2035 		adsize = sizeof(struct short_ad);
2036 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2037 		adsize = sizeof(struct long_ad);
2038 	else
2039 		return -EIO;
2040 
2041 	if (!epos->bh) {
2042 		WARN_ON(iinfo->i_lenAlloc !=
2043 			epos->offset - udf_file_entry_alloc_offset(inode));
2044 	} else {
2045 		aed = (struct allocExtDesc *)epos->bh->b_data;
2046 		WARN_ON(le32_to_cpu(aed->lengthAllocDescs) !=
2047 			epos->offset - sizeof(struct allocExtDesc));
2048 		WARN_ON(epos->offset + adsize > inode->i_sb->s_blocksize);
2049 	}
2050 
2051 	udf_write_aext(inode, epos, eloc, elen, inc);
2052 
2053 	if (!epos->bh) {
2054 		iinfo->i_lenAlloc += adsize;
2055 		mark_inode_dirty(inode);
2056 	} else {
2057 		aed = (struct allocExtDesc *)epos->bh->b_data;
2058 		le32_add_cpu(&aed->lengthAllocDescs, adsize);
2059 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2060 				UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2061 			udf_update_tag(epos->bh->b_data,
2062 					epos->offset + (inc ? 0 : adsize));
2063 		else
2064 			udf_update_tag(epos->bh->b_data,
2065 					sizeof(struct allocExtDesc));
2066 		mark_buffer_dirty_inode(epos->bh, inode);
2067 	}
2068 
2069 	return 0;
2070 }
2071 
2072 /*
2073  * Append extent at given position - should be the first free one in inode
2074  * / indirect extent. Takes care of allocating and linking indirect blocks.
2075  */
2076 int udf_add_aext(struct inode *inode, struct extent_position *epos,
2077 		 struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2078 {
2079 	int adsize;
2080 	struct super_block *sb = inode->i_sb;
2081 
2082 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2083 		adsize = sizeof(struct short_ad);
2084 	else if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2085 		adsize = sizeof(struct long_ad);
2086 	else
2087 		return -EIO;
2088 
2089 	if (epos->offset + (2 * adsize) > sb->s_blocksize) {
2090 		int err;
2091 		udf_pblk_t new_block;
2092 
2093 		new_block = udf_new_block(sb, NULL,
2094 					  epos->block.partitionReferenceNum,
2095 					  epos->block.logicalBlockNum, &err);
2096 		if (!new_block)
2097 			return -ENOSPC;
2098 
2099 		err = udf_setup_indirect_aext(inode, new_block, epos);
2100 		if (err)
2101 			return err;
2102 	}
2103 
2104 	return __udf_add_aext(inode, epos, eloc, elen, inc);
2105 }
2106 
2107 void udf_write_aext(struct inode *inode, struct extent_position *epos,
2108 		    struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2109 {
2110 	int adsize;
2111 	uint8_t *ptr;
2112 	struct short_ad *sad;
2113 	struct long_ad *lad;
2114 	struct udf_inode_info *iinfo = UDF_I(inode);
2115 
2116 	if (!epos->bh)
2117 		ptr = iinfo->i_data + epos->offset -
2118 			udf_file_entry_alloc_offset(inode) +
2119 			iinfo->i_lenEAttr;
2120 	else
2121 		ptr = epos->bh->b_data + epos->offset;
2122 
2123 	switch (iinfo->i_alloc_type) {
2124 	case ICBTAG_FLAG_AD_SHORT:
2125 		sad = (struct short_ad *)ptr;
2126 		sad->extLength = cpu_to_le32(elen);
2127 		sad->extPosition = cpu_to_le32(eloc->logicalBlockNum);
2128 		adsize = sizeof(struct short_ad);
2129 		break;
2130 	case ICBTAG_FLAG_AD_LONG:
2131 		lad = (struct long_ad *)ptr;
2132 		lad->extLength = cpu_to_le32(elen);
2133 		lad->extLocation = cpu_to_lelb(*eloc);
2134 		memset(lad->impUse, 0x00, sizeof(lad->impUse));
2135 		adsize = sizeof(struct long_ad);
2136 		break;
2137 	default:
2138 		return;
2139 	}
2140 
2141 	if (epos->bh) {
2142 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2143 		    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201) {
2144 			struct allocExtDesc *aed =
2145 				(struct allocExtDesc *)epos->bh->b_data;
2146 			udf_update_tag(epos->bh->b_data,
2147 				       le32_to_cpu(aed->lengthAllocDescs) +
2148 				       sizeof(struct allocExtDesc));
2149 		}
2150 		mark_buffer_dirty_inode(epos->bh, inode);
2151 	} else {
2152 		mark_inode_dirty(inode);
2153 	}
2154 
2155 	if (inc)
2156 		epos->offset += adsize;
2157 }
2158 
2159 /*
2160  * Only 1 indirect extent in a row really makes sense but allow upto 16 in case
2161  * someone does some weird stuff.
2162  */
2163 #define UDF_MAX_INDIR_EXTS 16
2164 
2165 int8_t udf_next_aext(struct inode *inode, struct extent_position *epos,
2166 		     struct kernel_lb_addr *eloc, uint32_t *elen, int inc)
2167 {
2168 	int8_t etype;
2169 	unsigned int indirections = 0;
2170 
2171 	while ((etype = udf_current_aext(inode, epos, eloc, elen, inc)) ==
2172 	       (EXT_NEXT_EXTENT_ALLOCDESCS >> 30)) {
2173 		udf_pblk_t block;
2174 
2175 		if (++indirections > UDF_MAX_INDIR_EXTS) {
2176 			udf_err(inode->i_sb,
2177 				"too many indirect extents in inode %lu\n",
2178 				inode->i_ino);
2179 			return -1;
2180 		}
2181 
2182 		epos->block = *eloc;
2183 		epos->offset = sizeof(struct allocExtDesc);
2184 		brelse(epos->bh);
2185 		block = udf_get_lb_pblock(inode->i_sb, &epos->block, 0);
2186 		epos->bh = sb_bread(inode->i_sb, block);
2187 		if (!epos->bh) {
2188 			udf_debug("reading block %u failed!\n", block);
2189 			return -1;
2190 		}
2191 	}
2192 
2193 	return etype;
2194 }
2195 
2196 int8_t udf_current_aext(struct inode *inode, struct extent_position *epos,
2197 			struct kernel_lb_addr *eloc, uint32_t *elen, int inc)
2198 {
2199 	int alen;
2200 	int8_t etype;
2201 	uint8_t *ptr;
2202 	struct short_ad *sad;
2203 	struct long_ad *lad;
2204 	struct udf_inode_info *iinfo = UDF_I(inode);
2205 
2206 	if (!epos->bh) {
2207 		if (!epos->offset)
2208 			epos->offset = udf_file_entry_alloc_offset(inode);
2209 		ptr = iinfo->i_data + epos->offset -
2210 			udf_file_entry_alloc_offset(inode) +
2211 			iinfo->i_lenEAttr;
2212 		alen = udf_file_entry_alloc_offset(inode) +
2213 							iinfo->i_lenAlloc;
2214 	} else {
2215 		if (!epos->offset)
2216 			epos->offset = sizeof(struct allocExtDesc);
2217 		ptr = epos->bh->b_data + epos->offset;
2218 		alen = sizeof(struct allocExtDesc) +
2219 			le32_to_cpu(((struct allocExtDesc *)epos->bh->b_data)->
2220 							lengthAllocDescs);
2221 	}
2222 
2223 	switch (iinfo->i_alloc_type) {
2224 	case ICBTAG_FLAG_AD_SHORT:
2225 		sad = udf_get_fileshortad(ptr, alen, &epos->offset, inc);
2226 		if (!sad)
2227 			return -1;
2228 		etype = le32_to_cpu(sad->extLength) >> 30;
2229 		eloc->logicalBlockNum = le32_to_cpu(sad->extPosition);
2230 		eloc->partitionReferenceNum =
2231 				iinfo->i_location.partitionReferenceNum;
2232 		*elen = le32_to_cpu(sad->extLength) & UDF_EXTENT_LENGTH_MASK;
2233 		break;
2234 	case ICBTAG_FLAG_AD_LONG:
2235 		lad = udf_get_filelongad(ptr, alen, &epos->offset, inc);
2236 		if (!lad)
2237 			return -1;
2238 		etype = le32_to_cpu(lad->extLength) >> 30;
2239 		*eloc = lelb_to_cpu(lad->extLocation);
2240 		*elen = le32_to_cpu(lad->extLength) & UDF_EXTENT_LENGTH_MASK;
2241 		break;
2242 	default:
2243 		udf_debug("alloc_type = %u unsupported\n", iinfo->i_alloc_type);
2244 		return -1;
2245 	}
2246 
2247 	return etype;
2248 }
2249 
2250 static int udf_insert_aext(struct inode *inode, struct extent_position epos,
2251 			   struct kernel_lb_addr neloc, uint32_t nelen)
2252 {
2253 	struct kernel_lb_addr oeloc;
2254 	uint32_t oelen;
2255 	int8_t etype;
2256 	int err;
2257 
2258 	if (epos.bh)
2259 		get_bh(epos.bh);
2260 
2261 	while ((etype = udf_next_aext(inode, &epos, &oeloc, &oelen, 0)) != -1) {
2262 		udf_write_aext(inode, &epos, &neloc, nelen, 1);
2263 		neloc = oeloc;
2264 		nelen = (etype << 30) | oelen;
2265 	}
2266 	err = udf_add_aext(inode, &epos, &neloc, nelen, 1);
2267 	brelse(epos.bh);
2268 
2269 	return err;
2270 }
2271 
2272 int8_t udf_delete_aext(struct inode *inode, struct extent_position epos)
2273 {
2274 	struct extent_position oepos;
2275 	int adsize;
2276 	int8_t etype;
2277 	struct allocExtDesc *aed;
2278 	struct udf_inode_info *iinfo;
2279 	struct kernel_lb_addr eloc;
2280 	uint32_t elen;
2281 
2282 	if (epos.bh) {
2283 		get_bh(epos.bh);
2284 		get_bh(epos.bh);
2285 	}
2286 
2287 	iinfo = UDF_I(inode);
2288 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2289 		adsize = sizeof(struct short_ad);
2290 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2291 		adsize = sizeof(struct long_ad);
2292 	else
2293 		adsize = 0;
2294 
2295 	oepos = epos;
2296 	if (udf_next_aext(inode, &epos, &eloc, &elen, 1) == -1)
2297 		return -1;
2298 
2299 	while ((etype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1) {
2300 		udf_write_aext(inode, &oepos, &eloc, (etype << 30) | elen, 1);
2301 		if (oepos.bh != epos.bh) {
2302 			oepos.block = epos.block;
2303 			brelse(oepos.bh);
2304 			get_bh(epos.bh);
2305 			oepos.bh = epos.bh;
2306 			oepos.offset = epos.offset - adsize;
2307 		}
2308 	}
2309 	memset(&eloc, 0x00, sizeof(struct kernel_lb_addr));
2310 	elen = 0;
2311 
2312 	if (epos.bh != oepos.bh) {
2313 		udf_free_blocks(inode->i_sb, inode, &epos.block, 0, 1);
2314 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2315 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2316 		if (!oepos.bh) {
2317 			iinfo->i_lenAlloc -= (adsize * 2);
2318 			mark_inode_dirty(inode);
2319 		} else {
2320 			aed = (struct allocExtDesc *)oepos.bh->b_data;
2321 			le32_add_cpu(&aed->lengthAllocDescs, -(2 * adsize));
2322 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2323 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2324 				udf_update_tag(oepos.bh->b_data,
2325 						oepos.offset - (2 * adsize));
2326 			else
2327 				udf_update_tag(oepos.bh->b_data,
2328 						sizeof(struct allocExtDesc));
2329 			mark_buffer_dirty_inode(oepos.bh, inode);
2330 		}
2331 	} else {
2332 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2333 		if (!oepos.bh) {
2334 			iinfo->i_lenAlloc -= adsize;
2335 			mark_inode_dirty(inode);
2336 		} else {
2337 			aed = (struct allocExtDesc *)oepos.bh->b_data;
2338 			le32_add_cpu(&aed->lengthAllocDescs, -adsize);
2339 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2340 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2341 				udf_update_tag(oepos.bh->b_data,
2342 						epos.offset - adsize);
2343 			else
2344 				udf_update_tag(oepos.bh->b_data,
2345 						sizeof(struct allocExtDesc));
2346 			mark_buffer_dirty_inode(oepos.bh, inode);
2347 		}
2348 	}
2349 
2350 	brelse(epos.bh);
2351 	brelse(oepos.bh);
2352 
2353 	return (elen >> 30);
2354 }
2355 
2356 int8_t inode_bmap(struct inode *inode, sector_t block,
2357 		  struct extent_position *pos, struct kernel_lb_addr *eloc,
2358 		  uint32_t *elen, sector_t *offset)
2359 {
2360 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
2361 	loff_t lbcount = 0, bcount = (loff_t) block << blocksize_bits;
2362 	int8_t etype;
2363 	struct udf_inode_info *iinfo;
2364 
2365 	iinfo = UDF_I(inode);
2366 	if (!udf_read_extent_cache(inode, bcount, &lbcount, pos)) {
2367 		pos->offset = 0;
2368 		pos->block = iinfo->i_location;
2369 		pos->bh = NULL;
2370 	}
2371 	*elen = 0;
2372 	do {
2373 		etype = udf_next_aext(inode, pos, eloc, elen, 1);
2374 		if (etype == -1) {
2375 			*offset = (bcount - lbcount) >> blocksize_bits;
2376 			iinfo->i_lenExtents = lbcount;
2377 			return -1;
2378 		}
2379 		lbcount += *elen;
2380 	} while (lbcount <= bcount);
2381 	/* update extent cache */
2382 	udf_update_extent_cache(inode, lbcount - *elen, pos);
2383 	*offset = (bcount + *elen - lbcount) >> blocksize_bits;
2384 
2385 	return etype;
2386 }
2387