xref: /linux/fs/udf/inode.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * inode.c
4  *
5  * PURPOSE
6  *  Inode handling routines for the OSTA-UDF(tm) filesystem.
7  *
8  * COPYRIGHT
9  *  (C) 1998 Dave Boynton
10  *  (C) 1998-2004 Ben Fennema
11  *  (C) 1999-2000 Stelias Computing Inc
12  *
13  * HISTORY
14  *
15  *  10/04/98 dgb  Added rudimentary directory functions
16  *  10/07/98      Fully working udf_block_map! It works!
17  *  11/25/98      bmap altered to better support extents
18  *  12/06/98 blf  partition support in udf_iget, udf_block_map
19  *                and udf_read_inode
20  *  12/12/98      rewrote udf_block_map to handle next extents and descs across
21  *                block boundaries (which is not actually allowed)
22  *  12/20/98      added support for strategy 4096
23  *  03/07/99      rewrote udf_block_map (again)
24  *                New funcs, inode_bmap, udf_next_aext
25  *  04/19/99      Support for writing device EA's for major/minor #
26  */
27 
28 #include "udfdecl.h"
29 #include <linux/mm.h>
30 #include <linux/module.h>
31 #include <linux/pagemap.h>
32 #include <linux/writeback.h>
33 #include <linux/slab.h>
34 #include <linux/crc-itu-t.h>
35 #include <linux/mpage.h>
36 #include <linux/uio.h>
37 #include <linux/bio.h>
38 
39 #include "udf_i.h"
40 #include "udf_sb.h"
41 
42 #define EXTENT_MERGE_SIZE 5
43 
44 #define FE_MAPPED_PERMS	(FE_PERM_U_READ | FE_PERM_U_WRITE | FE_PERM_U_EXEC | \
45 			 FE_PERM_G_READ | FE_PERM_G_WRITE | FE_PERM_G_EXEC | \
46 			 FE_PERM_O_READ | FE_PERM_O_WRITE | FE_PERM_O_EXEC)
47 
48 #define FE_DELETE_PERMS	(FE_PERM_U_DELETE | FE_PERM_G_DELETE | \
49 			 FE_PERM_O_DELETE)
50 
51 struct udf_map_rq;
52 
53 static umode_t udf_convert_permissions(struct fileEntry *);
54 static int udf_update_inode(struct inode *, int);
55 static int udf_sync_inode(struct inode *inode);
56 static int udf_alloc_i_data(struct inode *inode, size_t size);
57 static int inode_getblk(struct inode *inode, struct udf_map_rq *map);
58 static int udf_insert_aext(struct inode *, struct extent_position,
59 			   struct kernel_lb_addr, uint32_t);
60 static void udf_split_extents(struct inode *, int *, int, udf_pblk_t,
61 			      struct kernel_long_ad *, int *);
62 static void udf_prealloc_extents(struct inode *, int, int,
63 				 struct kernel_long_ad *, int *);
64 static void udf_merge_extents(struct inode *, struct kernel_long_ad *, int *);
65 static int udf_update_extents(struct inode *, struct kernel_long_ad *, int,
66 			      int, struct extent_position *);
67 static int udf_get_block_wb(struct inode *inode, sector_t block,
68 			    struct buffer_head *bh_result, int create);
69 
70 static void __udf_clear_extent_cache(struct inode *inode)
71 {
72 	struct udf_inode_info *iinfo = UDF_I(inode);
73 
74 	if (iinfo->cached_extent.lstart != -1) {
75 		brelse(iinfo->cached_extent.epos.bh);
76 		iinfo->cached_extent.lstart = -1;
77 	}
78 }
79 
80 /* Invalidate extent cache */
81 static void udf_clear_extent_cache(struct inode *inode)
82 {
83 	struct udf_inode_info *iinfo = UDF_I(inode);
84 
85 	spin_lock(&iinfo->i_extent_cache_lock);
86 	__udf_clear_extent_cache(inode);
87 	spin_unlock(&iinfo->i_extent_cache_lock);
88 }
89 
90 /* Return contents of extent cache */
91 static int udf_read_extent_cache(struct inode *inode, loff_t bcount,
92 				 loff_t *lbcount, struct extent_position *pos)
93 {
94 	struct udf_inode_info *iinfo = UDF_I(inode);
95 	int ret = 0;
96 
97 	spin_lock(&iinfo->i_extent_cache_lock);
98 	if ((iinfo->cached_extent.lstart <= bcount) &&
99 	    (iinfo->cached_extent.lstart != -1)) {
100 		/* Cache hit */
101 		*lbcount = iinfo->cached_extent.lstart;
102 		memcpy(pos, &iinfo->cached_extent.epos,
103 		       sizeof(struct extent_position));
104 		if (pos->bh)
105 			get_bh(pos->bh);
106 		ret = 1;
107 	}
108 	spin_unlock(&iinfo->i_extent_cache_lock);
109 	return ret;
110 }
111 
112 /* Add extent to extent cache */
113 static void udf_update_extent_cache(struct inode *inode, loff_t estart,
114 				    struct extent_position *pos)
115 {
116 	struct udf_inode_info *iinfo = UDF_I(inode);
117 
118 	spin_lock(&iinfo->i_extent_cache_lock);
119 	/* Invalidate previously cached extent */
120 	__udf_clear_extent_cache(inode);
121 	if (pos->bh)
122 		get_bh(pos->bh);
123 	memcpy(&iinfo->cached_extent.epos, pos, sizeof(*pos));
124 	iinfo->cached_extent.lstart = estart;
125 	switch (iinfo->i_alloc_type) {
126 	case ICBTAG_FLAG_AD_SHORT:
127 		iinfo->cached_extent.epos.offset -= sizeof(struct short_ad);
128 		break;
129 	case ICBTAG_FLAG_AD_LONG:
130 		iinfo->cached_extent.epos.offset -= sizeof(struct long_ad);
131 		break;
132 	}
133 	spin_unlock(&iinfo->i_extent_cache_lock);
134 }
135 
136 void udf_evict_inode(struct inode *inode)
137 {
138 	struct udf_inode_info *iinfo = UDF_I(inode);
139 	int want_delete = 0;
140 
141 	if (!is_bad_inode(inode)) {
142 		if (!inode->i_nlink) {
143 			want_delete = 1;
144 			udf_setsize(inode, 0);
145 			udf_update_inode(inode, IS_SYNC(inode));
146 		}
147 		if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB &&
148 		    inode->i_size != iinfo->i_lenExtents) {
149 			udf_warn(inode->i_sb,
150 				 "Inode %lu (mode %o) has inode size %llu different from extent length %llu. Filesystem need not be standards compliant.\n",
151 				 inode->i_ino, inode->i_mode,
152 				 (unsigned long long)inode->i_size,
153 				 (unsigned long long)iinfo->i_lenExtents);
154 		}
155 	}
156 	truncate_inode_pages_final(&inode->i_data);
157 	invalidate_inode_buffers(inode);
158 	clear_inode(inode);
159 	kfree(iinfo->i_data);
160 	iinfo->i_data = NULL;
161 	udf_clear_extent_cache(inode);
162 	if (want_delete) {
163 		udf_free_inode(inode);
164 	}
165 }
166 
167 static void udf_write_failed(struct address_space *mapping, loff_t to)
168 {
169 	struct inode *inode = mapping->host;
170 	struct udf_inode_info *iinfo = UDF_I(inode);
171 	loff_t isize = inode->i_size;
172 
173 	if (to > isize) {
174 		truncate_pagecache(inode, isize);
175 		if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
176 			down_write(&iinfo->i_data_sem);
177 			udf_clear_extent_cache(inode);
178 			udf_truncate_extents(inode);
179 			up_write(&iinfo->i_data_sem);
180 		}
181 	}
182 }
183 
184 static int udf_adinicb_writepage(struct folio *folio,
185 				 struct writeback_control *wbc, void *data)
186 {
187 	struct inode *inode = folio->mapping->host;
188 	struct udf_inode_info *iinfo = UDF_I(inode);
189 
190 	BUG_ON(!folio_test_locked(folio));
191 	BUG_ON(folio->index != 0);
192 	memcpy_from_file_folio(iinfo->i_data + iinfo->i_lenEAttr, folio, 0,
193 		       i_size_read(inode));
194 	folio_unlock(folio);
195 	mark_inode_dirty(inode);
196 
197 	return 0;
198 }
199 
200 static int udf_writepages(struct address_space *mapping,
201 			  struct writeback_control *wbc)
202 {
203 	struct inode *inode = mapping->host;
204 	struct udf_inode_info *iinfo = UDF_I(inode);
205 
206 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB)
207 		return mpage_writepages(mapping, wbc, udf_get_block_wb);
208 	return write_cache_pages(mapping, wbc, udf_adinicb_writepage, NULL);
209 }
210 
211 static void udf_adinicb_read_folio(struct folio *folio)
212 {
213 	struct inode *inode = folio->mapping->host;
214 	struct udf_inode_info *iinfo = UDF_I(inode);
215 	loff_t isize = i_size_read(inode);
216 
217 	folio_fill_tail(folio, 0, iinfo->i_data + iinfo->i_lenEAttr, isize);
218 	folio_mark_uptodate(folio);
219 }
220 
221 static int udf_read_folio(struct file *file, struct folio *folio)
222 {
223 	struct udf_inode_info *iinfo = UDF_I(file_inode(file));
224 
225 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
226 		udf_adinicb_read_folio(folio);
227 		folio_unlock(folio);
228 		return 0;
229 	}
230 	return mpage_read_folio(folio, udf_get_block);
231 }
232 
233 static void udf_readahead(struct readahead_control *rac)
234 {
235 	struct udf_inode_info *iinfo = UDF_I(rac->mapping->host);
236 
237 	/*
238 	 * No readahead needed for in-ICB files and udf_get_block() would get
239 	 * confused for such file anyway.
240 	 */
241 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
242 		return;
243 
244 	mpage_readahead(rac, udf_get_block);
245 }
246 
247 static int udf_write_begin(struct file *file, struct address_space *mapping,
248 			   loff_t pos, unsigned len,
249 			   struct page **pagep, void **fsdata)
250 {
251 	struct udf_inode_info *iinfo = UDF_I(file_inode(file));
252 	struct folio *folio;
253 	int ret;
254 
255 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
256 		ret = block_write_begin(mapping, pos, len, pagep,
257 					udf_get_block);
258 		if (unlikely(ret))
259 			udf_write_failed(mapping, pos + len);
260 		return ret;
261 	}
262 	if (WARN_ON_ONCE(pos >= PAGE_SIZE))
263 		return -EIO;
264 	folio = __filemap_get_folio(mapping, 0, FGP_WRITEBEGIN,
265 			mapping_gfp_mask(mapping));
266 	if (IS_ERR(folio))
267 		return PTR_ERR(folio);
268 	*pagep = &folio->page;
269 	if (!folio_test_uptodate(folio))
270 		udf_adinicb_read_folio(folio);
271 	return 0;
272 }
273 
274 static int udf_write_end(struct file *file, struct address_space *mapping,
275 			 loff_t pos, unsigned len, unsigned copied,
276 			 struct page *page, void *fsdata)
277 {
278 	struct inode *inode = file_inode(file);
279 	struct folio *folio;
280 	loff_t last_pos;
281 
282 	if (UDF_I(inode)->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB)
283 		return generic_write_end(file, mapping, pos, len, copied, page,
284 					 fsdata);
285 	folio = page_folio(page);
286 	last_pos = pos + copied;
287 	if (last_pos > inode->i_size)
288 		i_size_write(inode, last_pos);
289 	folio_mark_dirty(folio);
290 	folio_unlock(folio);
291 	folio_put(folio);
292 
293 	return copied;
294 }
295 
296 static ssize_t udf_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
297 {
298 	struct file *file = iocb->ki_filp;
299 	struct address_space *mapping = file->f_mapping;
300 	struct inode *inode = mapping->host;
301 	size_t count = iov_iter_count(iter);
302 	ssize_t ret;
303 
304 	/* Fallback to buffered IO for in-ICB files */
305 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
306 		return 0;
307 	ret = blockdev_direct_IO(iocb, inode, iter, udf_get_block);
308 	if (unlikely(ret < 0 && iov_iter_rw(iter) == WRITE))
309 		udf_write_failed(mapping, iocb->ki_pos + count);
310 	return ret;
311 }
312 
313 static sector_t udf_bmap(struct address_space *mapping, sector_t block)
314 {
315 	struct udf_inode_info *iinfo = UDF_I(mapping->host);
316 
317 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
318 		return -EINVAL;
319 	return generic_block_bmap(mapping, block, udf_get_block);
320 }
321 
322 const struct address_space_operations udf_aops = {
323 	.dirty_folio	= block_dirty_folio,
324 	.invalidate_folio = block_invalidate_folio,
325 	.read_folio	= udf_read_folio,
326 	.readahead	= udf_readahead,
327 	.writepages	= udf_writepages,
328 	.write_begin	= udf_write_begin,
329 	.write_end	= udf_write_end,
330 	.direct_IO	= udf_direct_IO,
331 	.bmap		= udf_bmap,
332 	.migrate_folio	= buffer_migrate_folio,
333 };
334 
335 /*
336  * Expand file stored in ICB to a normal one-block-file
337  *
338  * This function requires i_mutex held
339  */
340 int udf_expand_file_adinicb(struct inode *inode)
341 {
342 	struct folio *folio;
343 	struct udf_inode_info *iinfo = UDF_I(inode);
344 	int err;
345 
346 	WARN_ON_ONCE(!inode_is_locked(inode));
347 	if (!iinfo->i_lenAlloc) {
348 		down_write(&iinfo->i_data_sem);
349 		if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
350 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
351 		else
352 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
353 		up_write(&iinfo->i_data_sem);
354 		mark_inode_dirty(inode);
355 		return 0;
356 	}
357 
358 	folio = __filemap_get_folio(inode->i_mapping, 0,
359 			FGP_LOCK | FGP_ACCESSED | FGP_CREAT, GFP_KERNEL);
360 	if (IS_ERR(folio))
361 		return PTR_ERR(folio);
362 
363 	if (!folio_test_uptodate(folio))
364 		udf_adinicb_read_folio(folio);
365 	down_write(&iinfo->i_data_sem);
366 	memset(iinfo->i_data + iinfo->i_lenEAttr, 0x00,
367 	       iinfo->i_lenAlloc);
368 	iinfo->i_lenAlloc = 0;
369 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
370 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
371 	else
372 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
373 	folio_mark_dirty(folio);
374 	folio_unlock(folio);
375 	up_write(&iinfo->i_data_sem);
376 	err = filemap_fdatawrite(inode->i_mapping);
377 	if (err) {
378 		/* Restore everything back so that we don't lose data... */
379 		folio_lock(folio);
380 		down_write(&iinfo->i_data_sem);
381 		memcpy_from_folio(iinfo->i_data + iinfo->i_lenEAttr,
382 				folio, 0, inode->i_size);
383 		folio_unlock(folio);
384 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
385 		iinfo->i_lenAlloc = inode->i_size;
386 		up_write(&iinfo->i_data_sem);
387 	}
388 	folio_put(folio);
389 	mark_inode_dirty(inode);
390 
391 	return err;
392 }
393 
394 #define UDF_MAP_CREATE		0x01	/* Mapping can allocate new blocks */
395 #define UDF_MAP_NOPREALLOC	0x02	/* Do not preallocate blocks */
396 
397 #define UDF_BLK_MAPPED	0x01	/* Block was successfully mapped */
398 #define UDF_BLK_NEW	0x02	/* Block was freshly allocated */
399 
400 struct udf_map_rq {
401 	sector_t lblk;
402 	udf_pblk_t pblk;
403 	int iflags;		/* UDF_MAP_ flags determining behavior */
404 	int oflags;		/* UDF_BLK_ flags reporting results */
405 };
406 
407 static int udf_map_block(struct inode *inode, struct udf_map_rq *map)
408 {
409 	int err;
410 	struct udf_inode_info *iinfo = UDF_I(inode);
411 
412 	if (WARN_ON_ONCE(iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB))
413 		return -EFSCORRUPTED;
414 
415 	map->oflags = 0;
416 	if (!(map->iflags & UDF_MAP_CREATE)) {
417 		struct kernel_lb_addr eloc;
418 		uint32_t elen;
419 		sector_t offset;
420 		struct extent_position epos = {};
421 
422 		down_read(&iinfo->i_data_sem);
423 		if (inode_bmap(inode, map->lblk, &epos, &eloc, &elen, &offset)
424 				== (EXT_RECORDED_ALLOCATED >> 30)) {
425 			map->pblk = udf_get_lb_pblock(inode->i_sb, &eloc,
426 							offset);
427 			map->oflags |= UDF_BLK_MAPPED;
428 		}
429 		up_read(&iinfo->i_data_sem);
430 		brelse(epos.bh);
431 
432 		return 0;
433 	}
434 
435 	down_write(&iinfo->i_data_sem);
436 	/*
437 	 * Block beyond EOF and prealloc extents? Just discard preallocation
438 	 * as it is not useful and complicates things.
439 	 */
440 	if (((loff_t)map->lblk) << inode->i_blkbits >= iinfo->i_lenExtents)
441 		udf_discard_prealloc(inode);
442 	udf_clear_extent_cache(inode);
443 	err = inode_getblk(inode, map);
444 	up_write(&iinfo->i_data_sem);
445 	return err;
446 }
447 
448 static int __udf_get_block(struct inode *inode, sector_t block,
449 			   struct buffer_head *bh_result, int flags)
450 {
451 	int err;
452 	struct udf_map_rq map = {
453 		.lblk = block,
454 		.iflags = flags,
455 	};
456 
457 	err = udf_map_block(inode, &map);
458 	if (err < 0)
459 		return err;
460 	if (map.oflags & UDF_BLK_MAPPED) {
461 		map_bh(bh_result, inode->i_sb, map.pblk);
462 		if (map.oflags & UDF_BLK_NEW)
463 			set_buffer_new(bh_result);
464 	}
465 	return 0;
466 }
467 
468 int udf_get_block(struct inode *inode, sector_t block,
469 		  struct buffer_head *bh_result, int create)
470 {
471 	int flags = create ? UDF_MAP_CREATE : 0;
472 
473 	/*
474 	 * We preallocate blocks only for regular files. It also makes sense
475 	 * for directories but there's a problem when to drop the
476 	 * preallocation. We might use some delayed work for that but I feel
477 	 * it's overengineering for a filesystem like UDF.
478 	 */
479 	if (!S_ISREG(inode->i_mode))
480 		flags |= UDF_MAP_NOPREALLOC;
481 	return __udf_get_block(inode, block, bh_result, flags);
482 }
483 
484 /*
485  * We shouldn't be allocating blocks on page writeback since we allocate them
486  * on page fault. We can spot dirty buffers without allocated blocks though
487  * when truncate expands file. These however don't have valid data so we can
488  * safely ignore them. So never allocate blocks from page writeback.
489  */
490 static int udf_get_block_wb(struct inode *inode, sector_t block,
491 			    struct buffer_head *bh_result, int create)
492 {
493 	return __udf_get_block(inode, block, bh_result, 0);
494 }
495 
496 /* Extend the file with new blocks totaling 'new_block_bytes',
497  * return the number of extents added
498  */
499 static int udf_do_extend_file(struct inode *inode,
500 			      struct extent_position *last_pos,
501 			      struct kernel_long_ad *last_ext,
502 			      loff_t new_block_bytes)
503 {
504 	uint32_t add;
505 	int count = 0, fake = !(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
506 	struct super_block *sb = inode->i_sb;
507 	struct udf_inode_info *iinfo;
508 	int err;
509 
510 	/* The previous extent is fake and we should not extend by anything
511 	 * - there's nothing to do... */
512 	if (!new_block_bytes && fake)
513 		return 0;
514 
515 	iinfo = UDF_I(inode);
516 	/* Round the last extent up to a multiple of block size */
517 	if (last_ext->extLength & (sb->s_blocksize - 1)) {
518 		last_ext->extLength =
519 			(last_ext->extLength & UDF_EXTENT_FLAG_MASK) |
520 			(((last_ext->extLength & UDF_EXTENT_LENGTH_MASK) +
521 			  sb->s_blocksize - 1) & ~(sb->s_blocksize - 1));
522 		iinfo->i_lenExtents =
523 			(iinfo->i_lenExtents + sb->s_blocksize - 1) &
524 			~(sb->s_blocksize - 1);
525 	}
526 
527 	add = 0;
528 	/* Can we merge with the previous extent? */
529 	if ((last_ext->extLength & UDF_EXTENT_FLAG_MASK) ==
530 					EXT_NOT_RECORDED_NOT_ALLOCATED) {
531 		add = (1 << 30) - sb->s_blocksize -
532 			(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
533 		if (add > new_block_bytes)
534 			add = new_block_bytes;
535 		new_block_bytes -= add;
536 		last_ext->extLength += add;
537 	}
538 
539 	if (fake) {
540 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
541 				   last_ext->extLength, 1);
542 		if (err < 0)
543 			goto out_err;
544 		count++;
545 	} else {
546 		struct kernel_lb_addr tmploc;
547 		uint32_t tmplen;
548 
549 		udf_write_aext(inode, last_pos, &last_ext->extLocation,
550 				last_ext->extLength, 1);
551 
552 		/*
553 		 * We've rewritten the last extent. If we are going to add
554 		 * more extents, we may need to enter possible following
555 		 * empty indirect extent.
556 		 */
557 		if (new_block_bytes)
558 			udf_next_aext(inode, last_pos, &tmploc, &tmplen, 0);
559 	}
560 	iinfo->i_lenExtents += add;
561 
562 	/* Managed to do everything necessary? */
563 	if (!new_block_bytes)
564 		goto out;
565 
566 	/* All further extents will be NOT_RECORDED_NOT_ALLOCATED */
567 	last_ext->extLocation.logicalBlockNum = 0;
568 	last_ext->extLocation.partitionReferenceNum = 0;
569 	add = (1 << 30) - sb->s_blocksize;
570 	last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED | add;
571 
572 	/* Create enough extents to cover the whole hole */
573 	while (new_block_bytes > add) {
574 		new_block_bytes -= add;
575 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
576 				   last_ext->extLength, 1);
577 		if (err)
578 			goto out_err;
579 		iinfo->i_lenExtents += add;
580 		count++;
581 	}
582 	if (new_block_bytes) {
583 		last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
584 			new_block_bytes;
585 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
586 				   last_ext->extLength, 1);
587 		if (err)
588 			goto out_err;
589 		iinfo->i_lenExtents += new_block_bytes;
590 		count++;
591 	}
592 
593 out:
594 	/* last_pos should point to the last written extent... */
595 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
596 		last_pos->offset -= sizeof(struct short_ad);
597 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
598 		last_pos->offset -= sizeof(struct long_ad);
599 	else
600 		return -EIO;
601 
602 	return count;
603 out_err:
604 	/* Remove extents we've created so far */
605 	udf_clear_extent_cache(inode);
606 	udf_truncate_extents(inode);
607 	return err;
608 }
609 
610 /* Extend the final block of the file to final_block_len bytes */
611 static void udf_do_extend_final_block(struct inode *inode,
612 				      struct extent_position *last_pos,
613 				      struct kernel_long_ad *last_ext,
614 				      uint32_t new_elen)
615 {
616 	uint32_t added_bytes;
617 
618 	/*
619 	 * Extent already large enough? It may be already rounded up to block
620 	 * size...
621 	 */
622 	if (new_elen <= (last_ext->extLength & UDF_EXTENT_LENGTH_MASK))
623 		return;
624 	added_bytes = new_elen - (last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
625 	last_ext->extLength += added_bytes;
626 	UDF_I(inode)->i_lenExtents += added_bytes;
627 
628 	udf_write_aext(inode, last_pos, &last_ext->extLocation,
629 			last_ext->extLength, 1);
630 }
631 
632 static int udf_extend_file(struct inode *inode, loff_t newsize)
633 {
634 
635 	struct extent_position epos;
636 	struct kernel_lb_addr eloc;
637 	uint32_t elen;
638 	int8_t etype;
639 	struct super_block *sb = inode->i_sb;
640 	sector_t first_block = newsize >> sb->s_blocksize_bits, offset;
641 	loff_t new_elen;
642 	int adsize;
643 	struct udf_inode_info *iinfo = UDF_I(inode);
644 	struct kernel_long_ad extent;
645 	int err = 0;
646 	bool within_last_ext;
647 
648 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
649 		adsize = sizeof(struct short_ad);
650 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
651 		adsize = sizeof(struct long_ad);
652 	else
653 		BUG();
654 
655 	down_write(&iinfo->i_data_sem);
656 	/*
657 	 * When creating hole in file, just don't bother with preserving
658 	 * preallocation. It likely won't be very useful anyway.
659 	 */
660 	udf_discard_prealloc(inode);
661 
662 	etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset);
663 	within_last_ext = (etype != -1);
664 	/* We don't expect extents past EOF... */
665 	WARN_ON_ONCE(within_last_ext &&
666 		     elen > ((loff_t)offset + 1) << inode->i_blkbits);
667 
668 	if ((!epos.bh && epos.offset == udf_file_entry_alloc_offset(inode)) ||
669 	    (epos.bh && epos.offset == sizeof(struct allocExtDesc))) {
670 		/* File has no extents at all or has empty last
671 		 * indirect extent! Create a fake extent... */
672 		extent.extLocation.logicalBlockNum = 0;
673 		extent.extLocation.partitionReferenceNum = 0;
674 		extent.extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
675 	} else {
676 		epos.offset -= adsize;
677 		etype = udf_next_aext(inode, &epos, &extent.extLocation,
678 				      &extent.extLength, 0);
679 		extent.extLength |= etype << 30;
680 	}
681 
682 	new_elen = ((loff_t)offset << inode->i_blkbits) |
683 					(newsize & (sb->s_blocksize - 1));
684 
685 	/* File has extent covering the new size (could happen when extending
686 	 * inside a block)?
687 	 */
688 	if (within_last_ext) {
689 		/* Extending file within the last file block */
690 		udf_do_extend_final_block(inode, &epos, &extent, new_elen);
691 	} else {
692 		err = udf_do_extend_file(inode, &epos, &extent, new_elen);
693 	}
694 
695 	if (err < 0)
696 		goto out;
697 	err = 0;
698 out:
699 	brelse(epos.bh);
700 	up_write(&iinfo->i_data_sem);
701 	return err;
702 }
703 
704 static int inode_getblk(struct inode *inode, struct udf_map_rq *map)
705 {
706 	struct kernel_long_ad laarr[EXTENT_MERGE_SIZE];
707 	struct extent_position prev_epos, cur_epos, next_epos;
708 	int count = 0, startnum = 0, endnum = 0;
709 	uint32_t elen = 0, tmpelen;
710 	struct kernel_lb_addr eloc, tmpeloc;
711 	int c = 1;
712 	loff_t lbcount = 0, b_off = 0;
713 	udf_pblk_t newblocknum;
714 	sector_t offset = 0;
715 	int8_t etype;
716 	struct udf_inode_info *iinfo = UDF_I(inode);
717 	udf_pblk_t goal = 0, pgoal = iinfo->i_location.logicalBlockNum;
718 	int lastblock = 0;
719 	bool isBeyondEOF;
720 	int ret = 0;
721 
722 	prev_epos.offset = udf_file_entry_alloc_offset(inode);
723 	prev_epos.block = iinfo->i_location;
724 	prev_epos.bh = NULL;
725 	cur_epos = next_epos = prev_epos;
726 	b_off = (loff_t)map->lblk << inode->i_sb->s_blocksize_bits;
727 
728 	/* find the extent which contains the block we are looking for.
729 	   alternate between laarr[0] and laarr[1] for locations of the
730 	   current extent, and the previous extent */
731 	do {
732 		if (prev_epos.bh != cur_epos.bh) {
733 			brelse(prev_epos.bh);
734 			get_bh(cur_epos.bh);
735 			prev_epos.bh = cur_epos.bh;
736 		}
737 		if (cur_epos.bh != next_epos.bh) {
738 			brelse(cur_epos.bh);
739 			get_bh(next_epos.bh);
740 			cur_epos.bh = next_epos.bh;
741 		}
742 
743 		lbcount += elen;
744 
745 		prev_epos.block = cur_epos.block;
746 		cur_epos.block = next_epos.block;
747 
748 		prev_epos.offset = cur_epos.offset;
749 		cur_epos.offset = next_epos.offset;
750 
751 		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 1);
752 		if (etype == -1)
753 			break;
754 
755 		c = !c;
756 
757 		laarr[c].extLength = (etype << 30) | elen;
758 		laarr[c].extLocation = eloc;
759 
760 		if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
761 			pgoal = eloc.logicalBlockNum +
762 				((elen + inode->i_sb->s_blocksize - 1) >>
763 				 inode->i_sb->s_blocksize_bits);
764 
765 		count++;
766 	} while (lbcount + elen <= b_off);
767 
768 	b_off -= lbcount;
769 	offset = b_off >> inode->i_sb->s_blocksize_bits;
770 	/*
771 	 * Move prev_epos and cur_epos into indirect extent if we are at
772 	 * the pointer to it
773 	 */
774 	udf_next_aext(inode, &prev_epos, &tmpeloc, &tmpelen, 0);
775 	udf_next_aext(inode, &cur_epos, &tmpeloc, &tmpelen, 0);
776 
777 	/* if the extent is allocated and recorded, return the block
778 	   if the extent is not a multiple of the blocksize, round up */
779 
780 	if (etype == (EXT_RECORDED_ALLOCATED >> 30)) {
781 		if (elen & (inode->i_sb->s_blocksize - 1)) {
782 			elen = EXT_RECORDED_ALLOCATED |
783 				((elen + inode->i_sb->s_blocksize - 1) &
784 				 ~(inode->i_sb->s_blocksize - 1));
785 			iinfo->i_lenExtents =
786 				ALIGN(iinfo->i_lenExtents,
787 				      inode->i_sb->s_blocksize);
788 			udf_write_aext(inode, &cur_epos, &eloc, elen, 1);
789 		}
790 		map->oflags = UDF_BLK_MAPPED;
791 		map->pblk = udf_get_lb_pblock(inode->i_sb, &eloc, offset);
792 		goto out_free;
793 	}
794 
795 	/* Are we beyond EOF and preallocated extent? */
796 	if (etype == -1) {
797 		loff_t hole_len;
798 
799 		isBeyondEOF = true;
800 		if (count) {
801 			if (c)
802 				laarr[0] = laarr[1];
803 			startnum = 1;
804 		} else {
805 			/* Create a fake extent when there's not one */
806 			memset(&laarr[0].extLocation, 0x00,
807 				sizeof(struct kernel_lb_addr));
808 			laarr[0].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
809 			/* Will udf_do_extend_file() create real extent from
810 			   a fake one? */
811 			startnum = (offset > 0);
812 		}
813 		/* Create extents for the hole between EOF and offset */
814 		hole_len = (loff_t)offset << inode->i_blkbits;
815 		ret = udf_do_extend_file(inode, &prev_epos, laarr, hole_len);
816 		if (ret < 0)
817 			goto out_free;
818 		c = 0;
819 		offset = 0;
820 		count += ret;
821 		/*
822 		 * Is there any real extent? - otherwise we overwrite the fake
823 		 * one...
824 		 */
825 		if (count)
826 			c = !c;
827 		laarr[c].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
828 			inode->i_sb->s_blocksize;
829 		memset(&laarr[c].extLocation, 0x00,
830 			sizeof(struct kernel_lb_addr));
831 		count++;
832 		endnum = c + 1;
833 		lastblock = 1;
834 	} else {
835 		isBeyondEOF = false;
836 		endnum = startnum = ((count > 2) ? 2 : count);
837 
838 		/* if the current extent is in position 0,
839 		   swap it with the previous */
840 		if (!c && count != 1) {
841 			laarr[2] = laarr[0];
842 			laarr[0] = laarr[1];
843 			laarr[1] = laarr[2];
844 			c = 1;
845 		}
846 
847 		/* if the current block is located in an extent,
848 		   read the next extent */
849 		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 0);
850 		if (etype != -1) {
851 			laarr[c + 1].extLength = (etype << 30) | elen;
852 			laarr[c + 1].extLocation = eloc;
853 			count++;
854 			startnum++;
855 			endnum++;
856 		} else
857 			lastblock = 1;
858 	}
859 
860 	/* if the current extent is not recorded but allocated, get the
861 	 * block in the extent corresponding to the requested block */
862 	if ((laarr[c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30))
863 		newblocknum = laarr[c].extLocation.logicalBlockNum + offset;
864 	else { /* otherwise, allocate a new block */
865 		if (iinfo->i_next_alloc_block == map->lblk)
866 			goal = iinfo->i_next_alloc_goal;
867 
868 		if (!goal) {
869 			if (!(goal = pgoal)) /* XXX: what was intended here? */
870 				goal = iinfo->i_location.logicalBlockNum + 1;
871 		}
872 
873 		newblocknum = udf_new_block(inode->i_sb, inode,
874 				iinfo->i_location.partitionReferenceNum,
875 				goal, &ret);
876 		if (!newblocknum)
877 			goto out_free;
878 		if (isBeyondEOF)
879 			iinfo->i_lenExtents += inode->i_sb->s_blocksize;
880 	}
881 
882 	/* if the extent the requsted block is located in contains multiple
883 	 * blocks, split the extent into at most three extents. blocks prior
884 	 * to requested block, requested block, and blocks after requested
885 	 * block */
886 	udf_split_extents(inode, &c, offset, newblocknum, laarr, &endnum);
887 
888 	if (!(map->iflags & UDF_MAP_NOPREALLOC))
889 		udf_prealloc_extents(inode, c, lastblock, laarr, &endnum);
890 
891 	/* merge any continuous blocks in laarr */
892 	udf_merge_extents(inode, laarr, &endnum);
893 
894 	/* write back the new extents, inserting new extents if the new number
895 	 * of extents is greater than the old number, and deleting extents if
896 	 * the new number of extents is less than the old number */
897 	ret = udf_update_extents(inode, laarr, startnum, endnum, &prev_epos);
898 	if (ret < 0)
899 		goto out_free;
900 
901 	map->pblk = udf_get_pblock(inode->i_sb, newblocknum,
902 				iinfo->i_location.partitionReferenceNum, 0);
903 	if (!map->pblk) {
904 		ret = -EFSCORRUPTED;
905 		goto out_free;
906 	}
907 	map->oflags = UDF_BLK_NEW | UDF_BLK_MAPPED;
908 	iinfo->i_next_alloc_block = map->lblk + 1;
909 	iinfo->i_next_alloc_goal = newblocknum + 1;
910 	inode_set_ctime_current(inode);
911 
912 	if (IS_SYNC(inode))
913 		udf_sync_inode(inode);
914 	else
915 		mark_inode_dirty(inode);
916 	ret = 0;
917 out_free:
918 	brelse(prev_epos.bh);
919 	brelse(cur_epos.bh);
920 	brelse(next_epos.bh);
921 	return ret;
922 }
923 
924 static void udf_split_extents(struct inode *inode, int *c, int offset,
925 			       udf_pblk_t newblocknum,
926 			       struct kernel_long_ad *laarr, int *endnum)
927 {
928 	unsigned long blocksize = inode->i_sb->s_blocksize;
929 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
930 
931 	if ((laarr[*c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30) ||
932 	    (laarr[*c].extLength >> 30) ==
933 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
934 		int curr = *c;
935 		int blen = ((laarr[curr].extLength & UDF_EXTENT_LENGTH_MASK) +
936 			    blocksize - 1) >> blocksize_bits;
937 		int8_t etype = (laarr[curr].extLength >> 30);
938 
939 		if (blen == 1)
940 			;
941 		else if (!offset || blen == offset + 1) {
942 			laarr[curr + 2] = laarr[curr + 1];
943 			laarr[curr + 1] = laarr[curr];
944 		} else {
945 			laarr[curr + 3] = laarr[curr + 1];
946 			laarr[curr + 2] = laarr[curr + 1] = laarr[curr];
947 		}
948 
949 		if (offset) {
950 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
951 				udf_free_blocks(inode->i_sb, inode,
952 						&laarr[curr].extLocation,
953 						0, offset);
954 				laarr[curr].extLength =
955 					EXT_NOT_RECORDED_NOT_ALLOCATED |
956 					(offset << blocksize_bits);
957 				laarr[curr].extLocation.logicalBlockNum = 0;
958 				laarr[curr].extLocation.
959 						partitionReferenceNum = 0;
960 			} else
961 				laarr[curr].extLength = (etype << 30) |
962 					(offset << blocksize_bits);
963 			curr++;
964 			(*c)++;
965 			(*endnum)++;
966 		}
967 
968 		laarr[curr].extLocation.logicalBlockNum = newblocknum;
969 		if (etype == (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
970 			laarr[curr].extLocation.partitionReferenceNum =
971 				UDF_I(inode)->i_location.partitionReferenceNum;
972 		laarr[curr].extLength = EXT_RECORDED_ALLOCATED |
973 			blocksize;
974 		curr++;
975 
976 		if (blen != offset + 1) {
977 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
978 				laarr[curr].extLocation.logicalBlockNum +=
979 								offset + 1;
980 			laarr[curr].extLength = (etype << 30) |
981 				((blen - (offset + 1)) << blocksize_bits);
982 			curr++;
983 			(*endnum)++;
984 		}
985 	}
986 }
987 
988 static void udf_prealloc_extents(struct inode *inode, int c, int lastblock,
989 				 struct kernel_long_ad *laarr,
990 				 int *endnum)
991 {
992 	int start, length = 0, currlength = 0, i;
993 
994 	if (*endnum >= (c + 1)) {
995 		if (!lastblock)
996 			return;
997 		else
998 			start = c;
999 	} else {
1000 		if ((laarr[c + 1].extLength >> 30) ==
1001 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
1002 			start = c + 1;
1003 			length = currlength =
1004 				(((laarr[c + 1].extLength &
1005 					UDF_EXTENT_LENGTH_MASK) +
1006 				inode->i_sb->s_blocksize - 1) >>
1007 				inode->i_sb->s_blocksize_bits);
1008 		} else
1009 			start = c;
1010 	}
1011 
1012 	for (i = start + 1; i <= *endnum; i++) {
1013 		if (i == *endnum) {
1014 			if (lastblock)
1015 				length += UDF_DEFAULT_PREALLOC_BLOCKS;
1016 		} else if ((laarr[i].extLength >> 30) ==
1017 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
1018 			length += (((laarr[i].extLength &
1019 						UDF_EXTENT_LENGTH_MASK) +
1020 				    inode->i_sb->s_blocksize - 1) >>
1021 				    inode->i_sb->s_blocksize_bits);
1022 		} else
1023 			break;
1024 	}
1025 
1026 	if (length) {
1027 		int next = laarr[start].extLocation.logicalBlockNum +
1028 			(((laarr[start].extLength & UDF_EXTENT_LENGTH_MASK) +
1029 			  inode->i_sb->s_blocksize - 1) >>
1030 			  inode->i_sb->s_blocksize_bits);
1031 		int numalloc = udf_prealloc_blocks(inode->i_sb, inode,
1032 				laarr[start].extLocation.partitionReferenceNum,
1033 				next, (UDF_DEFAULT_PREALLOC_BLOCKS > length ?
1034 				length : UDF_DEFAULT_PREALLOC_BLOCKS) -
1035 				currlength);
1036 		if (numalloc) 	{
1037 			if (start == (c + 1))
1038 				laarr[start].extLength +=
1039 					(numalloc <<
1040 					 inode->i_sb->s_blocksize_bits);
1041 			else {
1042 				memmove(&laarr[c + 2], &laarr[c + 1],
1043 					sizeof(struct long_ad) * (*endnum - (c + 1)));
1044 				(*endnum)++;
1045 				laarr[c + 1].extLocation.logicalBlockNum = next;
1046 				laarr[c + 1].extLocation.partitionReferenceNum =
1047 					laarr[c].extLocation.
1048 							partitionReferenceNum;
1049 				laarr[c + 1].extLength =
1050 					EXT_NOT_RECORDED_ALLOCATED |
1051 					(numalloc <<
1052 					 inode->i_sb->s_blocksize_bits);
1053 				start = c + 1;
1054 			}
1055 
1056 			for (i = start + 1; numalloc && i < *endnum; i++) {
1057 				int elen = ((laarr[i].extLength &
1058 						UDF_EXTENT_LENGTH_MASK) +
1059 					    inode->i_sb->s_blocksize - 1) >>
1060 					    inode->i_sb->s_blocksize_bits;
1061 
1062 				if (elen > numalloc) {
1063 					laarr[i].extLength -=
1064 						(numalloc <<
1065 						 inode->i_sb->s_blocksize_bits);
1066 					numalloc = 0;
1067 				} else {
1068 					numalloc -= elen;
1069 					if (*endnum > (i + 1))
1070 						memmove(&laarr[i],
1071 							&laarr[i + 1],
1072 							sizeof(struct long_ad) *
1073 							(*endnum - (i + 1)));
1074 					i--;
1075 					(*endnum)--;
1076 				}
1077 			}
1078 			UDF_I(inode)->i_lenExtents +=
1079 				numalloc << inode->i_sb->s_blocksize_bits;
1080 		}
1081 	}
1082 }
1083 
1084 static void udf_merge_extents(struct inode *inode, struct kernel_long_ad *laarr,
1085 			      int *endnum)
1086 {
1087 	int i;
1088 	unsigned long blocksize = inode->i_sb->s_blocksize;
1089 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1090 
1091 	for (i = 0; i < (*endnum - 1); i++) {
1092 		struct kernel_long_ad *li /*l[i]*/ = &laarr[i];
1093 		struct kernel_long_ad *lip1 /*l[i plus 1]*/ = &laarr[i + 1];
1094 
1095 		if (((li->extLength >> 30) == (lip1->extLength >> 30)) &&
1096 			(((li->extLength >> 30) ==
1097 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) ||
1098 			((lip1->extLocation.logicalBlockNum -
1099 			  li->extLocation.logicalBlockNum) ==
1100 			(((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1101 			blocksize - 1) >> blocksize_bits)))) {
1102 
1103 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1104 			     (lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1105 			     blocksize - 1) <= UDF_EXTENT_LENGTH_MASK) {
1106 				li->extLength = lip1->extLength +
1107 					(((li->extLength &
1108 						UDF_EXTENT_LENGTH_MASK) +
1109 					 blocksize - 1) & ~(blocksize - 1));
1110 				if (*endnum > (i + 2))
1111 					memmove(&laarr[i + 1], &laarr[i + 2],
1112 						sizeof(struct long_ad) *
1113 						(*endnum - (i + 2)));
1114 				i--;
1115 				(*endnum)--;
1116 			}
1117 		} else if (((li->extLength >> 30) ==
1118 				(EXT_NOT_RECORDED_ALLOCATED >> 30)) &&
1119 			   ((lip1->extLength >> 30) ==
1120 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))) {
1121 			udf_free_blocks(inode->i_sb, inode, &li->extLocation, 0,
1122 					((li->extLength &
1123 					  UDF_EXTENT_LENGTH_MASK) +
1124 					 blocksize - 1) >> blocksize_bits);
1125 			li->extLocation.logicalBlockNum = 0;
1126 			li->extLocation.partitionReferenceNum = 0;
1127 
1128 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1129 			     (lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1130 			     blocksize - 1) & ~UDF_EXTENT_LENGTH_MASK) {
1131 				lip1->extLength = (lip1->extLength -
1132 						   (li->extLength &
1133 						   UDF_EXTENT_LENGTH_MASK) +
1134 						   UDF_EXTENT_LENGTH_MASK) &
1135 						   ~(blocksize - 1);
1136 				li->extLength = (li->extLength &
1137 						 UDF_EXTENT_FLAG_MASK) +
1138 						(UDF_EXTENT_LENGTH_MASK + 1) -
1139 						blocksize;
1140 			} else {
1141 				li->extLength = lip1->extLength +
1142 					(((li->extLength &
1143 						UDF_EXTENT_LENGTH_MASK) +
1144 					  blocksize - 1) & ~(blocksize - 1));
1145 				if (*endnum > (i + 2))
1146 					memmove(&laarr[i + 1], &laarr[i + 2],
1147 						sizeof(struct long_ad) *
1148 						(*endnum - (i + 2)));
1149 				i--;
1150 				(*endnum)--;
1151 			}
1152 		} else if ((li->extLength >> 30) ==
1153 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
1154 			udf_free_blocks(inode->i_sb, inode,
1155 					&li->extLocation, 0,
1156 					((li->extLength &
1157 						UDF_EXTENT_LENGTH_MASK) +
1158 					 blocksize - 1) >> blocksize_bits);
1159 			li->extLocation.logicalBlockNum = 0;
1160 			li->extLocation.partitionReferenceNum = 0;
1161 			li->extLength = (li->extLength &
1162 						UDF_EXTENT_LENGTH_MASK) |
1163 						EXT_NOT_RECORDED_NOT_ALLOCATED;
1164 		}
1165 	}
1166 }
1167 
1168 static int udf_update_extents(struct inode *inode, struct kernel_long_ad *laarr,
1169 			      int startnum, int endnum,
1170 			      struct extent_position *epos)
1171 {
1172 	int start = 0, i;
1173 	struct kernel_lb_addr tmploc;
1174 	uint32_t tmplen;
1175 	int err;
1176 
1177 	if (startnum > endnum) {
1178 		for (i = 0; i < (startnum - endnum); i++)
1179 			udf_delete_aext(inode, *epos);
1180 	} else if (startnum < endnum) {
1181 		for (i = 0; i < (endnum - startnum); i++) {
1182 			err = udf_insert_aext(inode, *epos,
1183 					      laarr[i].extLocation,
1184 					      laarr[i].extLength);
1185 			/*
1186 			 * If we fail here, we are likely corrupting the extent
1187 			 * list and leaking blocks. At least stop early to
1188 			 * limit the damage.
1189 			 */
1190 			if (err < 0)
1191 				return err;
1192 			udf_next_aext(inode, epos, &laarr[i].extLocation,
1193 				      &laarr[i].extLength, 1);
1194 			start++;
1195 		}
1196 	}
1197 
1198 	for (i = start; i < endnum; i++) {
1199 		udf_next_aext(inode, epos, &tmploc, &tmplen, 0);
1200 		udf_write_aext(inode, epos, &laarr[i].extLocation,
1201 			       laarr[i].extLength, 1);
1202 	}
1203 	return 0;
1204 }
1205 
1206 struct buffer_head *udf_bread(struct inode *inode, udf_pblk_t block,
1207 			      int create, int *err)
1208 {
1209 	struct buffer_head *bh = NULL;
1210 	struct udf_map_rq map = {
1211 		.lblk = block,
1212 		.iflags = UDF_MAP_NOPREALLOC | (create ? UDF_MAP_CREATE : 0),
1213 	};
1214 
1215 	*err = udf_map_block(inode, &map);
1216 	if (*err || !(map.oflags & UDF_BLK_MAPPED))
1217 		return NULL;
1218 
1219 	bh = sb_getblk(inode->i_sb, map.pblk);
1220 	if (!bh) {
1221 		*err = -ENOMEM;
1222 		return NULL;
1223 	}
1224 	if (map.oflags & UDF_BLK_NEW) {
1225 		lock_buffer(bh);
1226 		memset(bh->b_data, 0x00, inode->i_sb->s_blocksize);
1227 		set_buffer_uptodate(bh);
1228 		unlock_buffer(bh);
1229 		mark_buffer_dirty_inode(bh, inode);
1230 		return bh;
1231 	}
1232 
1233 	if (bh_read(bh, 0) >= 0)
1234 		return bh;
1235 
1236 	brelse(bh);
1237 	*err = -EIO;
1238 	return NULL;
1239 }
1240 
1241 int udf_setsize(struct inode *inode, loff_t newsize)
1242 {
1243 	int err = 0;
1244 	struct udf_inode_info *iinfo;
1245 	unsigned int bsize = i_blocksize(inode);
1246 
1247 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1248 	      S_ISLNK(inode->i_mode)))
1249 		return -EINVAL;
1250 
1251 	iinfo = UDF_I(inode);
1252 	if (newsize > inode->i_size) {
1253 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1254 			if (bsize >=
1255 			    (udf_file_entry_alloc_offset(inode) + newsize)) {
1256 				down_write(&iinfo->i_data_sem);
1257 				iinfo->i_lenAlloc = newsize;
1258 				up_write(&iinfo->i_data_sem);
1259 				goto set_size;
1260 			}
1261 			err = udf_expand_file_adinicb(inode);
1262 			if (err)
1263 				return err;
1264 		}
1265 		err = udf_extend_file(inode, newsize);
1266 		if (err)
1267 			return err;
1268 set_size:
1269 		truncate_setsize(inode, newsize);
1270 	} else {
1271 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1272 			down_write(&iinfo->i_data_sem);
1273 			udf_clear_extent_cache(inode);
1274 			memset(iinfo->i_data + iinfo->i_lenEAttr + newsize,
1275 			       0x00, bsize - newsize -
1276 			       udf_file_entry_alloc_offset(inode));
1277 			iinfo->i_lenAlloc = newsize;
1278 			truncate_setsize(inode, newsize);
1279 			up_write(&iinfo->i_data_sem);
1280 			goto update_time;
1281 		}
1282 		err = block_truncate_page(inode->i_mapping, newsize,
1283 					  udf_get_block);
1284 		if (err)
1285 			return err;
1286 		truncate_setsize(inode, newsize);
1287 		down_write(&iinfo->i_data_sem);
1288 		udf_clear_extent_cache(inode);
1289 		err = udf_truncate_extents(inode);
1290 		up_write(&iinfo->i_data_sem);
1291 		if (err)
1292 			return err;
1293 	}
1294 update_time:
1295 	inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
1296 	if (IS_SYNC(inode))
1297 		udf_sync_inode(inode);
1298 	else
1299 		mark_inode_dirty(inode);
1300 	return err;
1301 }
1302 
1303 /*
1304  * Maximum length of linked list formed by ICB hierarchy. The chosen number is
1305  * arbitrary - just that we hopefully don't limit any real use of rewritten
1306  * inode on write-once media but avoid looping for too long on corrupted media.
1307  */
1308 #define UDF_MAX_ICB_NESTING 1024
1309 
1310 static int udf_read_inode(struct inode *inode, bool hidden_inode)
1311 {
1312 	struct buffer_head *bh = NULL;
1313 	struct fileEntry *fe;
1314 	struct extendedFileEntry *efe;
1315 	uint16_t ident;
1316 	struct udf_inode_info *iinfo = UDF_I(inode);
1317 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1318 	struct kernel_lb_addr *iloc = &iinfo->i_location;
1319 	unsigned int link_count;
1320 	unsigned int indirections = 0;
1321 	int bs = inode->i_sb->s_blocksize;
1322 	int ret = -EIO;
1323 	uint32_t uid, gid;
1324 	struct timespec64 ts;
1325 
1326 reread:
1327 	if (iloc->partitionReferenceNum >= sbi->s_partitions) {
1328 		udf_debug("partition reference: %u > logical volume partitions: %u\n",
1329 			  iloc->partitionReferenceNum, sbi->s_partitions);
1330 		return -EIO;
1331 	}
1332 
1333 	if (iloc->logicalBlockNum >=
1334 	    sbi->s_partmaps[iloc->partitionReferenceNum].s_partition_len) {
1335 		udf_debug("block=%u, partition=%u out of range\n",
1336 			  iloc->logicalBlockNum, iloc->partitionReferenceNum);
1337 		return -EIO;
1338 	}
1339 
1340 	/*
1341 	 * Set defaults, but the inode is still incomplete!
1342 	 * Note: get_new_inode() sets the following on a new inode:
1343 	 *      i_sb = sb
1344 	 *      i_no = ino
1345 	 *      i_flags = sb->s_flags
1346 	 *      i_state = 0
1347 	 * clean_inode(): zero fills and sets
1348 	 *      i_count = 1
1349 	 *      i_nlink = 1
1350 	 *      i_op = NULL;
1351 	 */
1352 	bh = udf_read_ptagged(inode->i_sb, iloc, 0, &ident);
1353 	if (!bh) {
1354 		udf_err(inode->i_sb, "(ino %lu) failed !bh\n", inode->i_ino);
1355 		return -EIO;
1356 	}
1357 
1358 	if (ident != TAG_IDENT_FE && ident != TAG_IDENT_EFE &&
1359 	    ident != TAG_IDENT_USE) {
1360 		udf_err(inode->i_sb, "(ino %lu) failed ident=%u\n",
1361 			inode->i_ino, ident);
1362 		goto out;
1363 	}
1364 
1365 	fe = (struct fileEntry *)bh->b_data;
1366 	efe = (struct extendedFileEntry *)bh->b_data;
1367 
1368 	if (fe->icbTag.strategyType == cpu_to_le16(4096)) {
1369 		struct buffer_head *ibh;
1370 
1371 		ibh = udf_read_ptagged(inode->i_sb, iloc, 1, &ident);
1372 		if (ident == TAG_IDENT_IE && ibh) {
1373 			struct kernel_lb_addr loc;
1374 			struct indirectEntry *ie;
1375 
1376 			ie = (struct indirectEntry *)ibh->b_data;
1377 			loc = lelb_to_cpu(ie->indirectICB.extLocation);
1378 
1379 			if (ie->indirectICB.extLength) {
1380 				brelse(ibh);
1381 				memcpy(&iinfo->i_location, &loc,
1382 				       sizeof(struct kernel_lb_addr));
1383 				if (++indirections > UDF_MAX_ICB_NESTING) {
1384 					udf_err(inode->i_sb,
1385 						"too many ICBs in ICB hierarchy"
1386 						" (max %d supported)\n",
1387 						UDF_MAX_ICB_NESTING);
1388 					goto out;
1389 				}
1390 				brelse(bh);
1391 				goto reread;
1392 			}
1393 		}
1394 		brelse(ibh);
1395 	} else if (fe->icbTag.strategyType != cpu_to_le16(4)) {
1396 		udf_err(inode->i_sb, "unsupported strategy type: %u\n",
1397 			le16_to_cpu(fe->icbTag.strategyType));
1398 		goto out;
1399 	}
1400 	if (fe->icbTag.strategyType == cpu_to_le16(4))
1401 		iinfo->i_strat4096 = 0;
1402 	else /* if (fe->icbTag.strategyType == cpu_to_le16(4096)) */
1403 		iinfo->i_strat4096 = 1;
1404 
1405 	iinfo->i_alloc_type = le16_to_cpu(fe->icbTag.flags) &
1406 							ICBTAG_FLAG_AD_MASK;
1407 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_SHORT &&
1408 	    iinfo->i_alloc_type != ICBTAG_FLAG_AD_LONG &&
1409 	    iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
1410 		ret = -EIO;
1411 		goto out;
1412 	}
1413 	iinfo->i_hidden = hidden_inode;
1414 	iinfo->i_unique = 0;
1415 	iinfo->i_lenEAttr = 0;
1416 	iinfo->i_lenExtents = 0;
1417 	iinfo->i_lenAlloc = 0;
1418 	iinfo->i_next_alloc_block = 0;
1419 	iinfo->i_next_alloc_goal = 0;
1420 	if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_EFE)) {
1421 		iinfo->i_efe = 1;
1422 		iinfo->i_use = 0;
1423 		ret = udf_alloc_i_data(inode, bs -
1424 					sizeof(struct extendedFileEntry));
1425 		if (ret)
1426 			goto out;
1427 		memcpy(iinfo->i_data,
1428 		       bh->b_data + sizeof(struct extendedFileEntry),
1429 		       bs - sizeof(struct extendedFileEntry));
1430 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_FE)) {
1431 		iinfo->i_efe = 0;
1432 		iinfo->i_use = 0;
1433 		ret = udf_alloc_i_data(inode, bs - sizeof(struct fileEntry));
1434 		if (ret)
1435 			goto out;
1436 		memcpy(iinfo->i_data,
1437 		       bh->b_data + sizeof(struct fileEntry),
1438 		       bs - sizeof(struct fileEntry));
1439 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_USE)) {
1440 		iinfo->i_efe = 0;
1441 		iinfo->i_use = 1;
1442 		iinfo->i_lenAlloc = le32_to_cpu(
1443 				((struct unallocSpaceEntry *)bh->b_data)->
1444 				 lengthAllocDescs);
1445 		ret = udf_alloc_i_data(inode, bs -
1446 					sizeof(struct unallocSpaceEntry));
1447 		if (ret)
1448 			goto out;
1449 		memcpy(iinfo->i_data,
1450 		       bh->b_data + sizeof(struct unallocSpaceEntry),
1451 		       bs - sizeof(struct unallocSpaceEntry));
1452 		return 0;
1453 	}
1454 
1455 	ret = -EIO;
1456 	read_lock(&sbi->s_cred_lock);
1457 	uid = le32_to_cpu(fe->uid);
1458 	if (uid == UDF_INVALID_ID ||
1459 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_SET))
1460 		inode->i_uid = sbi->s_uid;
1461 	else
1462 		i_uid_write(inode, uid);
1463 
1464 	gid = le32_to_cpu(fe->gid);
1465 	if (gid == UDF_INVALID_ID ||
1466 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_SET))
1467 		inode->i_gid = sbi->s_gid;
1468 	else
1469 		i_gid_write(inode, gid);
1470 
1471 	if (fe->icbTag.fileType != ICBTAG_FILE_TYPE_DIRECTORY &&
1472 			sbi->s_fmode != UDF_INVALID_MODE)
1473 		inode->i_mode = sbi->s_fmode;
1474 	else if (fe->icbTag.fileType == ICBTAG_FILE_TYPE_DIRECTORY &&
1475 			sbi->s_dmode != UDF_INVALID_MODE)
1476 		inode->i_mode = sbi->s_dmode;
1477 	else
1478 		inode->i_mode = udf_convert_permissions(fe);
1479 	inode->i_mode &= ~sbi->s_umask;
1480 	iinfo->i_extraPerms = le32_to_cpu(fe->permissions) & ~FE_MAPPED_PERMS;
1481 
1482 	read_unlock(&sbi->s_cred_lock);
1483 
1484 	link_count = le16_to_cpu(fe->fileLinkCount);
1485 	if (!link_count) {
1486 		if (!hidden_inode) {
1487 			ret = -ESTALE;
1488 			goto out;
1489 		}
1490 		link_count = 1;
1491 	}
1492 	set_nlink(inode, link_count);
1493 
1494 	inode->i_size = le64_to_cpu(fe->informationLength);
1495 	iinfo->i_lenExtents = inode->i_size;
1496 
1497 	if (iinfo->i_efe == 0) {
1498 		inode->i_blocks = le64_to_cpu(fe->logicalBlocksRecorded) <<
1499 			(inode->i_sb->s_blocksize_bits - 9);
1500 
1501 		udf_disk_stamp_to_time(&ts, fe->accessTime);
1502 		inode_set_atime_to_ts(inode, ts);
1503 		udf_disk_stamp_to_time(&ts, fe->modificationTime);
1504 		inode_set_mtime_to_ts(inode, ts);
1505 		udf_disk_stamp_to_time(&ts, fe->attrTime);
1506 		inode_set_ctime_to_ts(inode, ts);
1507 
1508 		iinfo->i_unique = le64_to_cpu(fe->uniqueID);
1509 		iinfo->i_lenEAttr = le32_to_cpu(fe->lengthExtendedAttr);
1510 		iinfo->i_lenAlloc = le32_to_cpu(fe->lengthAllocDescs);
1511 		iinfo->i_checkpoint = le32_to_cpu(fe->checkpoint);
1512 		iinfo->i_streamdir = 0;
1513 		iinfo->i_lenStreams = 0;
1514 	} else {
1515 		inode->i_blocks = le64_to_cpu(efe->logicalBlocksRecorded) <<
1516 		    (inode->i_sb->s_blocksize_bits - 9);
1517 
1518 		udf_disk_stamp_to_time(&ts, efe->accessTime);
1519 		inode_set_atime_to_ts(inode, ts);
1520 		udf_disk_stamp_to_time(&ts, efe->modificationTime);
1521 		inode_set_mtime_to_ts(inode, ts);
1522 		udf_disk_stamp_to_time(&ts, efe->attrTime);
1523 		inode_set_ctime_to_ts(inode, ts);
1524 		udf_disk_stamp_to_time(&iinfo->i_crtime, efe->createTime);
1525 
1526 		iinfo->i_unique = le64_to_cpu(efe->uniqueID);
1527 		iinfo->i_lenEAttr = le32_to_cpu(efe->lengthExtendedAttr);
1528 		iinfo->i_lenAlloc = le32_to_cpu(efe->lengthAllocDescs);
1529 		iinfo->i_checkpoint = le32_to_cpu(efe->checkpoint);
1530 
1531 		/* Named streams */
1532 		iinfo->i_streamdir = (efe->streamDirectoryICB.extLength != 0);
1533 		iinfo->i_locStreamdir =
1534 			lelb_to_cpu(efe->streamDirectoryICB.extLocation);
1535 		iinfo->i_lenStreams = le64_to_cpu(efe->objectSize);
1536 		if (iinfo->i_lenStreams >= inode->i_size)
1537 			iinfo->i_lenStreams -= inode->i_size;
1538 		else
1539 			iinfo->i_lenStreams = 0;
1540 	}
1541 	inode->i_generation = iinfo->i_unique;
1542 
1543 	/*
1544 	 * Sanity check length of allocation descriptors and extended attrs to
1545 	 * avoid integer overflows
1546 	 */
1547 	if (iinfo->i_lenEAttr > bs || iinfo->i_lenAlloc > bs)
1548 		goto out;
1549 	/* Now do exact checks */
1550 	if (udf_file_entry_alloc_offset(inode) + iinfo->i_lenAlloc > bs)
1551 		goto out;
1552 	/* Sanity checks for files in ICB so that we don't get confused later */
1553 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1554 		/*
1555 		 * For file in ICB data is stored in allocation descriptor
1556 		 * so sizes should match
1557 		 */
1558 		if (iinfo->i_lenAlloc != inode->i_size)
1559 			goto out;
1560 		/* File in ICB has to fit in there... */
1561 		if (inode->i_size > bs - udf_file_entry_alloc_offset(inode))
1562 			goto out;
1563 	}
1564 
1565 	switch (fe->icbTag.fileType) {
1566 	case ICBTAG_FILE_TYPE_DIRECTORY:
1567 		inode->i_op = &udf_dir_inode_operations;
1568 		inode->i_fop = &udf_dir_operations;
1569 		inode->i_mode |= S_IFDIR;
1570 		inc_nlink(inode);
1571 		break;
1572 	case ICBTAG_FILE_TYPE_REALTIME:
1573 	case ICBTAG_FILE_TYPE_REGULAR:
1574 	case ICBTAG_FILE_TYPE_UNDEF:
1575 	case ICBTAG_FILE_TYPE_VAT20:
1576 		inode->i_data.a_ops = &udf_aops;
1577 		inode->i_op = &udf_file_inode_operations;
1578 		inode->i_fop = &udf_file_operations;
1579 		inode->i_mode |= S_IFREG;
1580 		break;
1581 	case ICBTAG_FILE_TYPE_BLOCK:
1582 		inode->i_mode |= S_IFBLK;
1583 		break;
1584 	case ICBTAG_FILE_TYPE_CHAR:
1585 		inode->i_mode |= S_IFCHR;
1586 		break;
1587 	case ICBTAG_FILE_TYPE_FIFO:
1588 		init_special_inode(inode, inode->i_mode | S_IFIFO, 0);
1589 		break;
1590 	case ICBTAG_FILE_TYPE_SOCKET:
1591 		init_special_inode(inode, inode->i_mode | S_IFSOCK, 0);
1592 		break;
1593 	case ICBTAG_FILE_TYPE_SYMLINK:
1594 		inode->i_data.a_ops = &udf_symlink_aops;
1595 		inode->i_op = &udf_symlink_inode_operations;
1596 		inode_nohighmem(inode);
1597 		inode->i_mode = S_IFLNK | 0777;
1598 		break;
1599 	case ICBTAG_FILE_TYPE_MAIN:
1600 		udf_debug("METADATA FILE-----\n");
1601 		break;
1602 	case ICBTAG_FILE_TYPE_MIRROR:
1603 		udf_debug("METADATA MIRROR FILE-----\n");
1604 		break;
1605 	case ICBTAG_FILE_TYPE_BITMAP:
1606 		udf_debug("METADATA BITMAP FILE-----\n");
1607 		break;
1608 	default:
1609 		udf_err(inode->i_sb, "(ino %lu) failed unknown file type=%u\n",
1610 			inode->i_ino, fe->icbTag.fileType);
1611 		goto out;
1612 	}
1613 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1614 		struct deviceSpec *dsea =
1615 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1616 		if (dsea) {
1617 			init_special_inode(inode, inode->i_mode,
1618 				MKDEV(le32_to_cpu(dsea->majorDeviceIdent),
1619 				      le32_to_cpu(dsea->minorDeviceIdent)));
1620 			/* Developer ID ??? */
1621 		} else
1622 			goto out;
1623 	}
1624 	ret = 0;
1625 out:
1626 	brelse(bh);
1627 	return ret;
1628 }
1629 
1630 static int udf_alloc_i_data(struct inode *inode, size_t size)
1631 {
1632 	struct udf_inode_info *iinfo = UDF_I(inode);
1633 	iinfo->i_data = kmalloc(size, GFP_KERNEL);
1634 	if (!iinfo->i_data)
1635 		return -ENOMEM;
1636 	return 0;
1637 }
1638 
1639 static umode_t udf_convert_permissions(struct fileEntry *fe)
1640 {
1641 	umode_t mode;
1642 	uint32_t permissions;
1643 	uint32_t flags;
1644 
1645 	permissions = le32_to_cpu(fe->permissions);
1646 	flags = le16_to_cpu(fe->icbTag.flags);
1647 
1648 	mode =	((permissions) & 0007) |
1649 		((permissions >> 2) & 0070) |
1650 		((permissions >> 4) & 0700) |
1651 		((flags & ICBTAG_FLAG_SETUID) ? S_ISUID : 0) |
1652 		((flags & ICBTAG_FLAG_SETGID) ? S_ISGID : 0) |
1653 		((flags & ICBTAG_FLAG_STICKY) ? S_ISVTX : 0);
1654 
1655 	return mode;
1656 }
1657 
1658 void udf_update_extra_perms(struct inode *inode, umode_t mode)
1659 {
1660 	struct udf_inode_info *iinfo = UDF_I(inode);
1661 
1662 	/*
1663 	 * UDF 2.01 sec. 3.3.3.3 Note 2:
1664 	 * In Unix, delete permission tracks write
1665 	 */
1666 	iinfo->i_extraPerms &= ~FE_DELETE_PERMS;
1667 	if (mode & 0200)
1668 		iinfo->i_extraPerms |= FE_PERM_U_DELETE;
1669 	if (mode & 0020)
1670 		iinfo->i_extraPerms |= FE_PERM_G_DELETE;
1671 	if (mode & 0002)
1672 		iinfo->i_extraPerms |= FE_PERM_O_DELETE;
1673 }
1674 
1675 int udf_write_inode(struct inode *inode, struct writeback_control *wbc)
1676 {
1677 	return udf_update_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
1678 }
1679 
1680 static int udf_sync_inode(struct inode *inode)
1681 {
1682 	return udf_update_inode(inode, 1);
1683 }
1684 
1685 static void udf_adjust_time(struct udf_inode_info *iinfo, struct timespec64 time)
1686 {
1687 	if (iinfo->i_crtime.tv_sec > time.tv_sec ||
1688 	    (iinfo->i_crtime.tv_sec == time.tv_sec &&
1689 	     iinfo->i_crtime.tv_nsec > time.tv_nsec))
1690 		iinfo->i_crtime = time;
1691 }
1692 
1693 static int udf_update_inode(struct inode *inode, int do_sync)
1694 {
1695 	struct buffer_head *bh = NULL;
1696 	struct fileEntry *fe;
1697 	struct extendedFileEntry *efe;
1698 	uint64_t lb_recorded;
1699 	uint32_t udfperms;
1700 	uint16_t icbflags;
1701 	uint16_t crclen;
1702 	int err = 0;
1703 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1704 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1705 	struct udf_inode_info *iinfo = UDF_I(inode);
1706 
1707 	bh = sb_getblk(inode->i_sb,
1708 			udf_get_lb_pblock(inode->i_sb, &iinfo->i_location, 0));
1709 	if (!bh) {
1710 		udf_debug("getblk failure\n");
1711 		return -EIO;
1712 	}
1713 
1714 	lock_buffer(bh);
1715 	memset(bh->b_data, 0, inode->i_sb->s_blocksize);
1716 	fe = (struct fileEntry *)bh->b_data;
1717 	efe = (struct extendedFileEntry *)bh->b_data;
1718 
1719 	if (iinfo->i_use) {
1720 		struct unallocSpaceEntry *use =
1721 			(struct unallocSpaceEntry *)bh->b_data;
1722 
1723 		use->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1724 		memcpy(bh->b_data + sizeof(struct unallocSpaceEntry),
1725 		       iinfo->i_data, inode->i_sb->s_blocksize -
1726 					sizeof(struct unallocSpaceEntry));
1727 		use->descTag.tagIdent = cpu_to_le16(TAG_IDENT_USE);
1728 		crclen = sizeof(struct unallocSpaceEntry);
1729 
1730 		goto finish;
1731 	}
1732 
1733 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_FORGET))
1734 		fe->uid = cpu_to_le32(UDF_INVALID_ID);
1735 	else
1736 		fe->uid = cpu_to_le32(i_uid_read(inode));
1737 
1738 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_FORGET))
1739 		fe->gid = cpu_to_le32(UDF_INVALID_ID);
1740 	else
1741 		fe->gid = cpu_to_le32(i_gid_read(inode));
1742 
1743 	udfperms = ((inode->i_mode & 0007)) |
1744 		   ((inode->i_mode & 0070) << 2) |
1745 		   ((inode->i_mode & 0700) << 4);
1746 
1747 	udfperms |= iinfo->i_extraPerms;
1748 	fe->permissions = cpu_to_le32(udfperms);
1749 
1750 	if (S_ISDIR(inode->i_mode) && inode->i_nlink > 0)
1751 		fe->fileLinkCount = cpu_to_le16(inode->i_nlink - 1);
1752 	else {
1753 		if (iinfo->i_hidden)
1754 			fe->fileLinkCount = cpu_to_le16(0);
1755 		else
1756 			fe->fileLinkCount = cpu_to_le16(inode->i_nlink);
1757 	}
1758 
1759 	fe->informationLength = cpu_to_le64(inode->i_size);
1760 
1761 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1762 		struct regid *eid;
1763 		struct deviceSpec *dsea =
1764 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1765 		if (!dsea) {
1766 			dsea = (struct deviceSpec *)
1767 				udf_add_extendedattr(inode,
1768 						     sizeof(struct deviceSpec) +
1769 						     sizeof(struct regid), 12, 0x3);
1770 			dsea->attrType = cpu_to_le32(12);
1771 			dsea->attrSubtype = 1;
1772 			dsea->attrLength = cpu_to_le32(
1773 						sizeof(struct deviceSpec) +
1774 						sizeof(struct regid));
1775 			dsea->impUseLength = cpu_to_le32(sizeof(struct regid));
1776 		}
1777 		eid = (struct regid *)dsea->impUse;
1778 		memset(eid, 0, sizeof(*eid));
1779 		strcpy(eid->ident, UDF_ID_DEVELOPER);
1780 		eid->identSuffix[0] = UDF_OS_CLASS_UNIX;
1781 		eid->identSuffix[1] = UDF_OS_ID_LINUX;
1782 		dsea->majorDeviceIdent = cpu_to_le32(imajor(inode));
1783 		dsea->minorDeviceIdent = cpu_to_le32(iminor(inode));
1784 	}
1785 
1786 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1787 		lb_recorded = 0; /* No extents => no blocks! */
1788 	else
1789 		lb_recorded =
1790 			(inode->i_blocks + (1 << (blocksize_bits - 9)) - 1) >>
1791 			(blocksize_bits - 9);
1792 
1793 	if (iinfo->i_efe == 0) {
1794 		memcpy(bh->b_data + sizeof(struct fileEntry),
1795 		       iinfo->i_data,
1796 		       inode->i_sb->s_blocksize - sizeof(struct fileEntry));
1797 		fe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
1798 
1799 		udf_time_to_disk_stamp(&fe->accessTime, inode_get_atime(inode));
1800 		udf_time_to_disk_stamp(&fe->modificationTime, inode_get_mtime(inode));
1801 		udf_time_to_disk_stamp(&fe->attrTime, inode_get_ctime(inode));
1802 		memset(&(fe->impIdent), 0, sizeof(struct regid));
1803 		strcpy(fe->impIdent.ident, UDF_ID_DEVELOPER);
1804 		fe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1805 		fe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1806 		fe->uniqueID = cpu_to_le64(iinfo->i_unique);
1807 		fe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
1808 		fe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1809 		fe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
1810 		fe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_FE);
1811 		crclen = sizeof(struct fileEntry);
1812 	} else {
1813 		memcpy(bh->b_data + sizeof(struct extendedFileEntry),
1814 		       iinfo->i_data,
1815 		       inode->i_sb->s_blocksize -
1816 					sizeof(struct extendedFileEntry));
1817 		efe->objectSize =
1818 			cpu_to_le64(inode->i_size + iinfo->i_lenStreams);
1819 		efe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
1820 
1821 		if (iinfo->i_streamdir) {
1822 			struct long_ad *icb_lad = &efe->streamDirectoryICB;
1823 
1824 			icb_lad->extLocation =
1825 				cpu_to_lelb(iinfo->i_locStreamdir);
1826 			icb_lad->extLength =
1827 				cpu_to_le32(inode->i_sb->s_blocksize);
1828 		}
1829 
1830 		udf_adjust_time(iinfo, inode_get_atime(inode));
1831 		udf_adjust_time(iinfo, inode_get_mtime(inode));
1832 		udf_adjust_time(iinfo, inode_get_ctime(inode));
1833 
1834 		udf_time_to_disk_stamp(&efe->accessTime,
1835 				       inode_get_atime(inode));
1836 		udf_time_to_disk_stamp(&efe->modificationTime,
1837 				       inode_get_mtime(inode));
1838 		udf_time_to_disk_stamp(&efe->createTime, iinfo->i_crtime);
1839 		udf_time_to_disk_stamp(&efe->attrTime, inode_get_ctime(inode));
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