xref: /linux/fs/udf/inode.c (revision 2775df6e5e324be9dc375f7db2c8d3042df72bbf)
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 folio **foliop, 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, foliop,
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 	*foliop = folio;
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 folio *folio, void *fsdata)
277 {
278 	struct inode *inode = file_inode(file);
279 	loff_t last_pos;
280 
281 	if (UDF_I(inode)->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB)
282 		return generic_write_end(file, mapping, pos, len, copied, folio,
283 					 fsdata);
284 	last_pos = pos + copied;
285 	if (last_pos > inode->i_size)
286 		i_size_write(inode, last_pos);
287 	folio_mark_dirty(folio);
288 	folio_unlock(folio);
289 	folio_put(folio);
290 
291 	return copied;
292 }
293 
294 static ssize_t udf_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
295 {
296 	struct file *file = iocb->ki_filp;
297 	struct address_space *mapping = file->f_mapping;
298 	struct inode *inode = mapping->host;
299 	size_t count = iov_iter_count(iter);
300 	ssize_t ret;
301 
302 	/* Fallback to buffered IO for in-ICB files */
303 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
304 		return 0;
305 	ret = blockdev_direct_IO(iocb, inode, iter, udf_get_block);
306 	if (unlikely(ret < 0 && iov_iter_rw(iter) == WRITE))
307 		udf_write_failed(mapping, iocb->ki_pos + count);
308 	return ret;
309 }
310 
311 static sector_t udf_bmap(struct address_space *mapping, sector_t block)
312 {
313 	struct udf_inode_info *iinfo = UDF_I(mapping->host);
314 
315 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
316 		return -EINVAL;
317 	return generic_block_bmap(mapping, block, udf_get_block);
318 }
319 
320 const struct address_space_operations udf_aops = {
321 	.dirty_folio	= block_dirty_folio,
322 	.invalidate_folio = block_invalidate_folio,
323 	.read_folio	= udf_read_folio,
324 	.readahead	= udf_readahead,
325 	.writepages	= udf_writepages,
326 	.write_begin	= udf_write_begin,
327 	.write_end	= udf_write_end,
328 	.direct_IO	= udf_direct_IO,
329 	.bmap		= udf_bmap,
330 	.migrate_folio	= buffer_migrate_folio,
331 };
332 
333 /*
334  * Expand file stored in ICB to a normal one-block-file
335  *
336  * This function requires i_mutex held
337  */
338 int udf_expand_file_adinicb(struct inode *inode)
339 {
340 	struct folio *folio;
341 	struct udf_inode_info *iinfo = UDF_I(inode);
342 	int err;
343 
344 	WARN_ON_ONCE(!inode_is_locked(inode));
345 	if (!iinfo->i_lenAlloc) {
346 		down_write(&iinfo->i_data_sem);
347 		if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
348 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
349 		else
350 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
351 		up_write(&iinfo->i_data_sem);
352 		mark_inode_dirty(inode);
353 		return 0;
354 	}
355 
356 	folio = __filemap_get_folio(inode->i_mapping, 0,
357 			FGP_LOCK | FGP_ACCESSED | FGP_CREAT, GFP_KERNEL);
358 	if (IS_ERR(folio))
359 		return PTR_ERR(folio);
360 
361 	if (!folio_test_uptodate(folio))
362 		udf_adinicb_read_folio(folio);
363 	down_write(&iinfo->i_data_sem);
364 	memset(iinfo->i_data + iinfo->i_lenEAttr, 0x00,
365 	       iinfo->i_lenAlloc);
366 	iinfo->i_lenAlloc = 0;
367 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
368 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
369 	else
370 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
371 	folio_mark_dirty(folio);
372 	folio_unlock(folio);
373 	up_write(&iinfo->i_data_sem);
374 	err = filemap_fdatawrite(inode->i_mapping);
375 	if (err) {
376 		/* Restore everything back so that we don't lose data... */
377 		folio_lock(folio);
378 		down_write(&iinfo->i_data_sem);
379 		memcpy_from_folio(iinfo->i_data + iinfo->i_lenEAttr,
380 				folio, 0, inode->i_size);
381 		folio_unlock(folio);
382 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
383 		iinfo->i_lenAlloc = inode->i_size;
384 		up_write(&iinfo->i_data_sem);
385 	}
386 	folio_put(folio);
387 	mark_inode_dirty(inode);
388 
389 	return err;
390 }
391 
392 #define UDF_MAP_CREATE		0x01	/* Mapping can allocate new blocks */
393 #define UDF_MAP_NOPREALLOC	0x02	/* Do not preallocate blocks */
394 
395 #define UDF_BLK_MAPPED	0x01	/* Block was successfully mapped */
396 #define UDF_BLK_NEW	0x02	/* Block was freshly allocated */
397 
398 struct udf_map_rq {
399 	sector_t lblk;
400 	udf_pblk_t pblk;
401 	int iflags;		/* UDF_MAP_ flags determining behavior */
402 	int oflags;		/* UDF_BLK_ flags reporting results */
403 };
404 
405 static int udf_map_block(struct inode *inode, struct udf_map_rq *map)
406 {
407 	int err;
408 	struct udf_inode_info *iinfo = UDF_I(inode);
409 
410 	if (WARN_ON_ONCE(iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB))
411 		return -EFSCORRUPTED;
412 
413 	map->oflags = 0;
414 	if (!(map->iflags & UDF_MAP_CREATE)) {
415 		struct kernel_lb_addr eloc;
416 		uint32_t elen;
417 		sector_t offset;
418 		struct extent_position epos = {};
419 
420 		down_read(&iinfo->i_data_sem);
421 		if (inode_bmap(inode, map->lblk, &epos, &eloc, &elen, &offset)
422 				== (EXT_RECORDED_ALLOCATED >> 30)) {
423 			map->pblk = udf_get_lb_pblock(inode->i_sb, &eloc,
424 							offset);
425 			map->oflags |= UDF_BLK_MAPPED;
426 		}
427 		up_read(&iinfo->i_data_sem);
428 		brelse(epos.bh);
429 
430 		return 0;
431 	}
432 
433 	down_write(&iinfo->i_data_sem);
434 	/*
435 	 * Block beyond EOF and prealloc extents? Just discard preallocation
436 	 * as it is not useful and complicates things.
437 	 */
438 	if (((loff_t)map->lblk) << inode->i_blkbits >= iinfo->i_lenExtents)
439 		udf_discard_prealloc(inode);
440 	udf_clear_extent_cache(inode);
441 	err = inode_getblk(inode, map);
442 	up_write(&iinfo->i_data_sem);
443 	return err;
444 }
445 
446 static int __udf_get_block(struct inode *inode, sector_t block,
447 			   struct buffer_head *bh_result, int flags)
448 {
449 	int err;
450 	struct udf_map_rq map = {
451 		.lblk = block,
452 		.iflags = flags,
453 	};
454 
455 	err = udf_map_block(inode, &map);
456 	if (err < 0)
457 		return err;
458 	if (map.oflags & UDF_BLK_MAPPED) {
459 		map_bh(bh_result, inode->i_sb, map.pblk);
460 		if (map.oflags & UDF_BLK_NEW)
461 			set_buffer_new(bh_result);
462 	}
463 	return 0;
464 }
465 
466 int udf_get_block(struct inode *inode, sector_t block,
467 		  struct buffer_head *bh_result, int create)
468 {
469 	int flags = create ? UDF_MAP_CREATE : 0;
470 
471 	/*
472 	 * We preallocate blocks only for regular files. It also makes sense
473 	 * for directories but there's a problem when to drop the
474 	 * preallocation. We might use some delayed work for that but I feel
475 	 * it's overengineering for a filesystem like UDF.
476 	 */
477 	if (!S_ISREG(inode->i_mode))
478 		flags |= UDF_MAP_NOPREALLOC;
479 	return __udf_get_block(inode, block, bh_result, flags);
480 }
481 
482 /*
483  * We shouldn't be allocating blocks on page writeback since we allocate them
484  * on page fault. We can spot dirty buffers without allocated blocks though
485  * when truncate expands file. These however don't have valid data so we can
486  * safely ignore them. So never allocate blocks from page writeback.
487  */
488 static int udf_get_block_wb(struct inode *inode, sector_t block,
489 			    struct buffer_head *bh_result, int create)
490 {
491 	return __udf_get_block(inode, block, bh_result, 0);
492 }
493 
494 /* Extend the file with new blocks totaling 'new_block_bytes',
495  * return the number of extents added
496  */
497 static int udf_do_extend_file(struct inode *inode,
498 			      struct extent_position *last_pos,
499 			      struct kernel_long_ad *last_ext,
500 			      loff_t new_block_bytes)
501 {
502 	uint32_t add;
503 	int count = 0, fake = !(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
504 	struct super_block *sb = inode->i_sb;
505 	struct udf_inode_info *iinfo;
506 	int err;
507 
508 	/* The previous extent is fake and we should not extend by anything
509 	 * - there's nothing to do... */
510 	if (!new_block_bytes && fake)
511 		return 0;
512 
513 	iinfo = UDF_I(inode);
514 	/* Round the last extent up to a multiple of block size */
515 	if (last_ext->extLength & (sb->s_blocksize - 1)) {
516 		last_ext->extLength =
517 			(last_ext->extLength & UDF_EXTENT_FLAG_MASK) |
518 			(((last_ext->extLength & UDF_EXTENT_LENGTH_MASK) +
519 			  sb->s_blocksize - 1) & ~(sb->s_blocksize - 1));
520 		iinfo->i_lenExtents =
521 			(iinfo->i_lenExtents + sb->s_blocksize - 1) &
522 			~(sb->s_blocksize - 1);
523 	}
524 
525 	add = 0;
526 	/* Can we merge with the previous extent? */
527 	if ((last_ext->extLength & UDF_EXTENT_FLAG_MASK) ==
528 					EXT_NOT_RECORDED_NOT_ALLOCATED) {
529 		add = (1 << 30) - sb->s_blocksize -
530 			(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
531 		if (add > new_block_bytes)
532 			add = new_block_bytes;
533 		new_block_bytes -= add;
534 		last_ext->extLength += add;
535 	}
536 
537 	if (fake) {
538 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
539 				   last_ext->extLength, 1);
540 		if (err < 0)
541 			goto out_err;
542 		count++;
543 	} else {
544 		struct kernel_lb_addr tmploc;
545 		uint32_t tmplen;
546 
547 		udf_write_aext(inode, last_pos, &last_ext->extLocation,
548 				last_ext->extLength, 1);
549 
550 		/*
551 		 * We've rewritten the last extent. If we are going to add
552 		 * more extents, we may need to enter possible following
553 		 * empty indirect extent.
554 		 */
555 		if (new_block_bytes)
556 			udf_next_aext(inode, last_pos, &tmploc, &tmplen, 0);
557 	}
558 	iinfo->i_lenExtents += add;
559 
560 	/* Managed to do everything necessary? */
561 	if (!new_block_bytes)
562 		goto out;
563 
564 	/* All further extents will be NOT_RECORDED_NOT_ALLOCATED */
565 	last_ext->extLocation.logicalBlockNum = 0;
566 	last_ext->extLocation.partitionReferenceNum = 0;
567 	add = (1 << 30) - sb->s_blocksize;
568 	last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED | add;
569 
570 	/* Create enough extents to cover the whole hole */
571 	while (new_block_bytes > add) {
572 		new_block_bytes -= add;
573 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
574 				   last_ext->extLength, 1);
575 		if (err)
576 			goto out_err;
577 		iinfo->i_lenExtents += add;
578 		count++;
579 	}
580 	if (new_block_bytes) {
581 		last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
582 			new_block_bytes;
583 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
584 				   last_ext->extLength, 1);
585 		if (err)
586 			goto out_err;
587 		iinfo->i_lenExtents += new_block_bytes;
588 		count++;
589 	}
590 
591 out:
592 	/* last_pos should point to the last written extent... */
593 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
594 		last_pos->offset -= sizeof(struct short_ad);
595 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
596 		last_pos->offset -= sizeof(struct long_ad);
597 	else
598 		return -EIO;
599 
600 	return count;
601 out_err:
602 	/* Remove extents we've created so far */
603 	udf_clear_extent_cache(inode);
604 	udf_truncate_extents(inode);
605 	return err;
606 }
607 
608 /* Extend the final block of the file to final_block_len bytes */
609 static void udf_do_extend_final_block(struct inode *inode,
610 				      struct extent_position *last_pos,
611 				      struct kernel_long_ad *last_ext,
612 				      uint32_t new_elen)
613 {
614 	uint32_t added_bytes;
615 
616 	/*
617 	 * Extent already large enough? It may be already rounded up to block
618 	 * size...
619 	 */
620 	if (new_elen <= (last_ext->extLength & UDF_EXTENT_LENGTH_MASK))
621 		return;
622 	added_bytes = new_elen - (last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
623 	last_ext->extLength += added_bytes;
624 	UDF_I(inode)->i_lenExtents += added_bytes;
625 
626 	udf_write_aext(inode, last_pos, &last_ext->extLocation,
627 			last_ext->extLength, 1);
628 }
629 
630 static int udf_extend_file(struct inode *inode, loff_t newsize)
631 {
632 
633 	struct extent_position epos;
634 	struct kernel_lb_addr eloc;
635 	uint32_t elen;
636 	int8_t etype;
637 	struct super_block *sb = inode->i_sb;
638 	sector_t first_block = newsize >> sb->s_blocksize_bits, offset;
639 	loff_t new_elen;
640 	int adsize;
641 	struct udf_inode_info *iinfo = UDF_I(inode);
642 	struct kernel_long_ad extent;
643 	int err = 0;
644 	bool within_last_ext;
645 
646 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
647 		adsize = sizeof(struct short_ad);
648 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
649 		adsize = sizeof(struct long_ad);
650 	else
651 		BUG();
652 
653 	down_write(&iinfo->i_data_sem);
654 	/*
655 	 * When creating hole in file, just don't bother with preserving
656 	 * preallocation. It likely won't be very useful anyway.
657 	 */
658 	udf_discard_prealloc(inode);
659 
660 	etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset);
661 	within_last_ext = (etype != -1);
662 	/* We don't expect extents past EOF... */
663 	WARN_ON_ONCE(within_last_ext &&
664 		     elen > ((loff_t)offset + 1) << inode->i_blkbits);
665 
666 	if ((!epos.bh && epos.offset == udf_file_entry_alloc_offset(inode)) ||
667 	    (epos.bh && epos.offset == sizeof(struct allocExtDesc))) {
668 		/* File has no extents at all or has empty last
669 		 * indirect extent! Create a fake extent... */
670 		extent.extLocation.logicalBlockNum = 0;
671 		extent.extLocation.partitionReferenceNum = 0;
672 		extent.extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
673 	} else {
674 		epos.offset -= adsize;
675 		etype = udf_next_aext(inode, &epos, &extent.extLocation,
676 				      &extent.extLength, 0);
677 		extent.extLength |= etype << 30;
678 	}
679 
680 	new_elen = ((loff_t)offset << inode->i_blkbits) |
681 					(newsize & (sb->s_blocksize - 1));
682 
683 	/* File has extent covering the new size (could happen when extending
684 	 * inside a block)?
685 	 */
686 	if (within_last_ext) {
687 		/* Extending file within the last file block */
688 		udf_do_extend_final_block(inode, &epos, &extent, new_elen);
689 	} else {
690 		err = udf_do_extend_file(inode, &epos, &extent, new_elen);
691 	}
692 
693 	if (err < 0)
694 		goto out;
695 	err = 0;
696 out:
697 	brelse(epos.bh);
698 	up_write(&iinfo->i_data_sem);
699 	return err;
700 }
701 
702 static int inode_getblk(struct inode *inode, struct udf_map_rq *map)
703 {
704 	struct kernel_long_ad laarr[EXTENT_MERGE_SIZE];
705 	struct extent_position prev_epos, cur_epos, next_epos;
706 	int count = 0, startnum = 0, endnum = 0;
707 	uint32_t elen = 0, tmpelen;
708 	struct kernel_lb_addr eloc, tmpeloc;
709 	int c = 1;
710 	loff_t lbcount = 0, b_off = 0;
711 	udf_pblk_t newblocknum;
712 	sector_t offset = 0;
713 	int8_t etype;
714 	struct udf_inode_info *iinfo = UDF_I(inode);
715 	udf_pblk_t goal = 0, pgoal = iinfo->i_location.logicalBlockNum;
716 	int lastblock = 0;
717 	bool isBeyondEOF;
718 	int ret = 0;
719 
720 	prev_epos.offset = udf_file_entry_alloc_offset(inode);
721 	prev_epos.block = iinfo->i_location;
722 	prev_epos.bh = NULL;
723 	cur_epos = next_epos = prev_epos;
724 	b_off = (loff_t)map->lblk << inode->i_sb->s_blocksize_bits;
725 
726 	/* find the extent which contains the block we are looking for.
727 	   alternate between laarr[0] and laarr[1] for locations of the
728 	   current extent, and the previous extent */
729 	do {
730 		if (prev_epos.bh != cur_epos.bh) {
731 			brelse(prev_epos.bh);
732 			get_bh(cur_epos.bh);
733 			prev_epos.bh = cur_epos.bh;
734 		}
735 		if (cur_epos.bh != next_epos.bh) {
736 			brelse(cur_epos.bh);
737 			get_bh(next_epos.bh);
738 			cur_epos.bh = next_epos.bh;
739 		}
740 
741 		lbcount += elen;
742 
743 		prev_epos.block = cur_epos.block;
744 		cur_epos.block = next_epos.block;
745 
746 		prev_epos.offset = cur_epos.offset;
747 		cur_epos.offset = next_epos.offset;
748 
749 		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 1);
750 		if (etype == -1)
751 			break;
752 
753 		c = !c;
754 
755 		laarr[c].extLength = (etype << 30) | elen;
756 		laarr[c].extLocation = eloc;
757 
758 		if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
759 			pgoal = eloc.logicalBlockNum +
760 				((elen + inode->i_sb->s_blocksize - 1) >>
761 				 inode->i_sb->s_blocksize_bits);
762 
763 		count++;
764 	} while (lbcount + elen <= b_off);
765 
766 	b_off -= lbcount;
767 	offset = b_off >> inode->i_sb->s_blocksize_bits;
768 	/*
769 	 * Move prev_epos and cur_epos into indirect extent if we are at
770 	 * the pointer to it
771 	 */
772 	udf_next_aext(inode, &prev_epos, &tmpeloc, &tmpelen, 0);
773 	udf_next_aext(inode, &cur_epos, &tmpeloc, &tmpelen, 0);
774 
775 	/* if the extent is allocated and recorded, return the block
776 	   if the extent is not a multiple of the blocksize, round up */
777 
778 	if (etype == (EXT_RECORDED_ALLOCATED >> 30)) {
779 		if (elen & (inode->i_sb->s_blocksize - 1)) {
780 			elen = EXT_RECORDED_ALLOCATED |
781 				((elen + inode->i_sb->s_blocksize - 1) &
782 				 ~(inode->i_sb->s_blocksize - 1));
783 			iinfo->i_lenExtents =
784 				ALIGN(iinfo->i_lenExtents,
785 				      inode->i_sb->s_blocksize);
786 			udf_write_aext(inode, &cur_epos, &eloc, elen, 1);
787 		}
788 		map->oflags = UDF_BLK_MAPPED;
789 		map->pblk = udf_get_lb_pblock(inode->i_sb, &eloc, offset);
790 		goto out_free;
791 	}
792 
793 	/* Are we beyond EOF and preallocated extent? */
794 	if (etype == -1) {
795 		loff_t hole_len;
796 
797 		isBeyondEOF = true;
798 		if (count) {
799 			if (c)
800 				laarr[0] = laarr[1];
801 			startnum = 1;
802 		} else {
803 			/* Create a fake extent when there's not one */
804 			memset(&laarr[0].extLocation, 0x00,
805 				sizeof(struct kernel_lb_addr));
806 			laarr[0].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
807 			/* Will udf_do_extend_file() create real extent from
808 			   a fake one? */
809 			startnum = (offset > 0);
810 		}
811 		/* Create extents for the hole between EOF and offset */
812 		hole_len = (loff_t)offset << inode->i_blkbits;
813 		ret = udf_do_extend_file(inode, &prev_epos, laarr, hole_len);
814 		if (ret < 0)
815 			goto out_free;
816 		c = 0;
817 		offset = 0;
818 		count += ret;
819 		/*
820 		 * Is there any real extent? - otherwise we overwrite the fake
821 		 * one...
822 		 */
823 		if (count)
824 			c = !c;
825 		laarr[c].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
826 			inode->i_sb->s_blocksize;
827 		memset(&laarr[c].extLocation, 0x00,
828 			sizeof(struct kernel_lb_addr));
829 		count++;
830 		endnum = c + 1;
831 		lastblock = 1;
832 	} else {
833 		isBeyondEOF = false;
834 		endnum = startnum = ((count > 2) ? 2 : count);
835 
836 		/* if the current extent is in position 0,
837 		   swap it with the previous */
838 		if (!c && count != 1) {
839 			laarr[2] = laarr[0];
840 			laarr[0] = laarr[1];
841 			laarr[1] = laarr[2];
842 			c = 1;
843 		}
844 
845 		/* if the current block is located in an extent,
846 		   read the next extent */
847 		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 0);
848 		if (etype != -1) {
849 			laarr[c + 1].extLength = (etype << 30) | elen;
850 			laarr[c + 1].extLocation = eloc;
851 			count++;
852 			startnum++;
853 			endnum++;
854 		} else
855 			lastblock = 1;
856 	}
857 
858 	/* if the current extent is not recorded but allocated, get the
859 	 * block in the extent corresponding to the requested block */
860 	if ((laarr[c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30))
861 		newblocknum = laarr[c].extLocation.logicalBlockNum + offset;
862 	else { /* otherwise, allocate a new block */
863 		if (iinfo->i_next_alloc_block == map->lblk)
864 			goal = iinfo->i_next_alloc_goal;
865 
866 		if (!goal) {
867 			if (!(goal = pgoal)) /* XXX: what was intended here? */
868 				goal = iinfo->i_location.logicalBlockNum + 1;
869 		}
870 
871 		newblocknum = udf_new_block(inode->i_sb, inode,
872 				iinfo->i_location.partitionReferenceNum,
873 				goal, &ret);
874 		if (!newblocknum)
875 			goto out_free;
876 		if (isBeyondEOF)
877 			iinfo->i_lenExtents += inode->i_sb->s_blocksize;
878 	}
879 
880 	/* if the extent the requsted block is located in contains multiple
881 	 * blocks, split the extent into at most three extents. blocks prior
882 	 * to requested block, requested block, and blocks after requested
883 	 * block */
884 	udf_split_extents(inode, &c, offset, newblocknum, laarr, &endnum);
885 
886 	if (!(map->iflags & UDF_MAP_NOPREALLOC))
887 		udf_prealloc_extents(inode, c, lastblock, laarr, &endnum);
888 
889 	/* merge any continuous blocks in laarr */
890 	udf_merge_extents(inode, laarr, &endnum);
891 
892 	/* write back the new extents, inserting new extents if the new number
893 	 * of extents is greater than the old number, and deleting extents if
894 	 * the new number of extents is less than the old number */
895 	ret = udf_update_extents(inode, laarr, startnum, endnum, &prev_epos);
896 	if (ret < 0)
897 		goto out_free;
898 
899 	map->pblk = udf_get_pblock(inode->i_sb, newblocknum,
900 				iinfo->i_location.partitionReferenceNum, 0);
901 	if (!map->pblk) {
902 		ret = -EFSCORRUPTED;
903 		goto out_free;
904 	}
905 	map->oflags = UDF_BLK_NEW | UDF_BLK_MAPPED;
906 	iinfo->i_next_alloc_block = map->lblk + 1;
907 	iinfo->i_next_alloc_goal = newblocknum + 1;
908 	inode_set_ctime_current(inode);
909 
910 	if (IS_SYNC(inode))
911 		udf_sync_inode(inode);
912 	else
913 		mark_inode_dirty(inode);
914 	ret = 0;
915 out_free:
916 	brelse(prev_epos.bh);
917 	brelse(cur_epos.bh);
918 	brelse(next_epos.bh);
919 	return ret;
920 }
921 
922 static void udf_split_extents(struct inode *inode, int *c, int offset,
923 			       udf_pblk_t newblocknum,
924 			       struct kernel_long_ad *laarr, int *endnum)
925 {
926 	unsigned long blocksize = inode->i_sb->s_blocksize;
927 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
928 
929 	if ((laarr[*c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30) ||
930 	    (laarr[*c].extLength >> 30) ==
931 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
932 		int curr = *c;
933 		int blen = ((laarr[curr].extLength & UDF_EXTENT_LENGTH_MASK) +
934 			    blocksize - 1) >> blocksize_bits;
935 		int8_t etype = (laarr[curr].extLength >> 30);
936 
937 		if (blen == 1)
938 			;
939 		else if (!offset || blen == offset + 1) {
940 			laarr[curr + 2] = laarr[curr + 1];
941 			laarr[curr + 1] = laarr[curr];
942 		} else {
943 			laarr[curr + 3] = laarr[curr + 1];
944 			laarr[curr + 2] = laarr[curr + 1] = laarr[curr];
945 		}
946 
947 		if (offset) {
948 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
949 				udf_free_blocks(inode->i_sb, inode,
950 						&laarr[curr].extLocation,
951 						0, offset);
952 				laarr[curr].extLength =
953 					EXT_NOT_RECORDED_NOT_ALLOCATED |
954 					(offset << blocksize_bits);
955 				laarr[curr].extLocation.logicalBlockNum = 0;
956 				laarr[curr].extLocation.
957 						partitionReferenceNum = 0;
958 			} else
959 				laarr[curr].extLength = (etype << 30) |
960 					(offset << blocksize_bits);
961 			curr++;
962 			(*c)++;
963 			(*endnum)++;
964 		}
965 
966 		laarr[curr].extLocation.logicalBlockNum = newblocknum;
967 		if (etype == (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
968 			laarr[curr].extLocation.partitionReferenceNum =
969 				UDF_I(inode)->i_location.partitionReferenceNum;
970 		laarr[curr].extLength = EXT_RECORDED_ALLOCATED |
971 			blocksize;
972 		curr++;
973 
974 		if (blen != offset + 1) {
975 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
976 				laarr[curr].extLocation.logicalBlockNum +=
977 								offset + 1;
978 			laarr[curr].extLength = (etype << 30) |
979 				((blen - (offset + 1)) << blocksize_bits);
980 			curr++;
981 			(*endnum)++;
982 		}
983 	}
984 }
985 
986 static void udf_prealloc_extents(struct inode *inode, int c, int lastblock,
987 				 struct kernel_long_ad *laarr,
988 				 int *endnum)
989 {
990 	int start, length = 0, currlength = 0, i;
991 
992 	if (*endnum >= (c + 1)) {
993 		if (!lastblock)
994 			return;
995 		else
996 			start = c;
997 	} else {
998 		if ((laarr[c + 1].extLength >> 30) ==
999 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
1000 			start = c + 1;
1001 			length = currlength =
1002 				(((laarr[c + 1].extLength &
1003 					UDF_EXTENT_LENGTH_MASK) +
1004 				inode->i_sb->s_blocksize - 1) >>
1005 				inode->i_sb->s_blocksize_bits);
1006 		} else
1007 			start = c;
1008 	}
1009 
1010 	for (i = start + 1; i <= *endnum; i++) {
1011 		if (i == *endnum) {
1012 			if (lastblock)
1013 				length += UDF_DEFAULT_PREALLOC_BLOCKS;
1014 		} else if ((laarr[i].extLength >> 30) ==
1015 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
1016 			length += (((laarr[i].extLength &
1017 						UDF_EXTENT_LENGTH_MASK) +
1018 				    inode->i_sb->s_blocksize - 1) >>
1019 				    inode->i_sb->s_blocksize_bits);
1020 		} else
1021 			break;
1022 	}
1023 
1024 	if (length) {
1025 		int next = laarr[start].extLocation.logicalBlockNum +
1026 			(((laarr[start].extLength & UDF_EXTENT_LENGTH_MASK) +
1027 			  inode->i_sb->s_blocksize - 1) >>
1028 			  inode->i_sb->s_blocksize_bits);
1029 		int numalloc = udf_prealloc_blocks(inode->i_sb, inode,
1030 				laarr[start].extLocation.partitionReferenceNum,
1031 				next, (UDF_DEFAULT_PREALLOC_BLOCKS > length ?
1032 				length : UDF_DEFAULT_PREALLOC_BLOCKS) -
1033 				currlength);
1034 		if (numalloc) 	{
1035 			if (start == (c + 1))
1036 				laarr[start].extLength +=
1037 					(numalloc <<
1038 					 inode->i_sb->s_blocksize_bits);
1039 			else {
1040 				memmove(&laarr[c + 2], &laarr[c + 1],
1041 					sizeof(struct long_ad) * (*endnum - (c + 1)));
1042 				(*endnum)++;
1043 				laarr[c + 1].extLocation.logicalBlockNum = next;
1044 				laarr[c + 1].extLocation.partitionReferenceNum =
1045 					laarr[c].extLocation.
1046 							partitionReferenceNum;
1047 				laarr[c + 1].extLength =
1048 					EXT_NOT_RECORDED_ALLOCATED |
1049 					(numalloc <<
1050 					 inode->i_sb->s_blocksize_bits);
1051 				start = c + 1;
1052 			}
1053 
1054 			for (i = start + 1; numalloc && i < *endnum; i++) {
1055 				int elen = ((laarr[i].extLength &
1056 						UDF_EXTENT_LENGTH_MASK) +
1057 					    inode->i_sb->s_blocksize - 1) >>
1058 					    inode->i_sb->s_blocksize_bits;
1059 
1060 				if (elen > numalloc) {
1061 					laarr[i].extLength -=
1062 						(numalloc <<
1063 						 inode->i_sb->s_blocksize_bits);
1064 					numalloc = 0;
1065 				} else {
1066 					numalloc -= elen;
1067 					if (*endnum > (i + 1))
1068 						memmove(&laarr[i],
1069 							&laarr[i + 1],
1070 							sizeof(struct long_ad) *
1071 							(*endnum - (i + 1)));
1072 					i--;
1073 					(*endnum)--;
1074 				}
1075 			}
1076 			UDF_I(inode)->i_lenExtents +=
1077 				numalloc << inode->i_sb->s_blocksize_bits;
1078 		}
1079 	}
1080 }
1081 
1082 static void udf_merge_extents(struct inode *inode, struct kernel_long_ad *laarr,
1083 			      int *endnum)
1084 {
1085 	int i;
1086 	unsigned long blocksize = inode->i_sb->s_blocksize;
1087 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1088 
1089 	for (i = 0; i < (*endnum - 1); i++) {
1090 		struct kernel_long_ad *li /*l[i]*/ = &laarr[i];
1091 		struct kernel_long_ad *lip1 /*l[i plus 1]*/ = &laarr[i + 1];
1092 
1093 		if (((li->extLength >> 30) == (lip1->extLength >> 30)) &&
1094 			(((li->extLength >> 30) ==
1095 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) ||
1096 			((lip1->extLocation.logicalBlockNum -
1097 			  li->extLocation.logicalBlockNum) ==
1098 			(((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1099 			blocksize - 1) >> blocksize_bits)))) {
1100 
1101 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1102 			     (lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1103 			     blocksize - 1) <= UDF_EXTENT_LENGTH_MASK) {
1104 				li->extLength = lip1->extLength +
1105 					(((li->extLength &
1106 						UDF_EXTENT_LENGTH_MASK) +
1107 					 blocksize - 1) & ~(blocksize - 1));
1108 				if (*endnum > (i + 2))
1109 					memmove(&laarr[i + 1], &laarr[i + 2],
1110 						sizeof(struct long_ad) *
1111 						(*endnum - (i + 2)));
1112 				i--;
1113 				(*endnum)--;
1114 			}
1115 		} else if (((li->extLength >> 30) ==
1116 				(EXT_NOT_RECORDED_ALLOCATED >> 30)) &&
1117 			   ((lip1->extLength >> 30) ==
1118 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))) {
1119 			udf_free_blocks(inode->i_sb, inode, &li->extLocation, 0,
1120 					((li->extLength &
1121 					  UDF_EXTENT_LENGTH_MASK) +
1122 					 blocksize - 1) >> blocksize_bits);
1123 			li->extLocation.logicalBlockNum = 0;
1124 			li->extLocation.partitionReferenceNum = 0;
1125 
1126 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1127 			     (lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1128 			     blocksize - 1) & ~UDF_EXTENT_LENGTH_MASK) {
1129 				lip1->extLength = (lip1->extLength -
1130 						   (li->extLength &
1131 						   UDF_EXTENT_LENGTH_MASK) +
1132 						   UDF_EXTENT_LENGTH_MASK) &
1133 						   ~(blocksize - 1);
1134 				li->extLength = (li->extLength &
1135 						 UDF_EXTENT_FLAG_MASK) +
1136 						(UDF_EXTENT_LENGTH_MASK + 1) -
1137 						blocksize;
1138 			} else {
1139 				li->extLength = lip1->extLength +
1140 					(((li->extLength &
1141 						UDF_EXTENT_LENGTH_MASK) +
1142 					  blocksize - 1) & ~(blocksize - 1));
1143 				if (*endnum > (i + 2))
1144 					memmove(&laarr[i + 1], &laarr[i + 2],
1145 						sizeof(struct long_ad) *
1146 						(*endnum - (i + 2)));
1147 				i--;
1148 				(*endnum)--;
1149 			}
1150 		} else if ((li->extLength >> 30) ==
1151 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
1152 			udf_free_blocks(inode->i_sb, inode,
1153 					&li->extLocation, 0,
1154 					((li->extLength &
1155 						UDF_EXTENT_LENGTH_MASK) +
1156 					 blocksize - 1) >> blocksize_bits);
1157 			li->extLocation.logicalBlockNum = 0;
1158 			li->extLocation.partitionReferenceNum = 0;
1159 			li->extLength = (li->extLength &
1160 						UDF_EXTENT_LENGTH_MASK) |
1161 						EXT_NOT_RECORDED_NOT_ALLOCATED;
1162 		}
1163 	}
1164 }
1165 
1166 static int udf_update_extents(struct inode *inode, struct kernel_long_ad *laarr,
1167 			      int startnum, int endnum,
1168 			      struct extent_position *epos)
1169 {
1170 	int start = 0, i;
1171 	struct kernel_lb_addr tmploc;
1172 	uint32_t tmplen;
1173 	int err;
1174 
1175 	if (startnum > endnum) {
1176 		for (i = 0; i < (startnum - endnum); i++)
1177 			udf_delete_aext(inode, *epos);
1178 	} else if (startnum < endnum) {
1179 		for (i = 0; i < (endnum - startnum); i++) {
1180 			err = udf_insert_aext(inode, *epos,
1181 					      laarr[i].extLocation,
1182 					      laarr[i].extLength);
1183 			/*
1184 			 * If we fail here, we are likely corrupting the extent
1185 			 * list and leaking blocks. At least stop early to
1186 			 * limit the damage.
1187 			 */
1188 			if (err < 0)
1189 				return err;
1190 			udf_next_aext(inode, epos, &laarr[i].extLocation,
1191 				      &laarr[i].extLength, 1);
1192 			start++;
1193 		}
1194 	}
1195 
1196 	for (i = start; i < endnum; i++) {
1197 		udf_next_aext(inode, epos, &tmploc, &tmplen, 0);
1198 		udf_write_aext(inode, epos, &laarr[i].extLocation,
1199 			       laarr[i].extLength, 1);
1200 	}
1201 	return 0;
1202 }
1203 
1204 struct buffer_head *udf_bread(struct inode *inode, udf_pblk_t block,
1205 			      int create, int *err)
1206 {
1207 	struct buffer_head *bh = NULL;
1208 	struct udf_map_rq map = {
1209 		.lblk = block,
1210 		.iflags = UDF_MAP_NOPREALLOC | (create ? UDF_MAP_CREATE : 0),
1211 	};
1212 
1213 	*err = udf_map_block(inode, &map);
1214 	if (*err || !(map.oflags & UDF_BLK_MAPPED))
1215 		return NULL;
1216 
1217 	bh = sb_getblk(inode->i_sb, map.pblk);
1218 	if (!bh) {
1219 		*err = -ENOMEM;
1220 		return NULL;
1221 	}
1222 	if (map.oflags & UDF_BLK_NEW) {
1223 		lock_buffer(bh);
1224 		memset(bh->b_data, 0x00, inode->i_sb->s_blocksize);
1225 		set_buffer_uptodate(bh);
1226 		unlock_buffer(bh);
1227 		mark_buffer_dirty_inode(bh, inode);
1228 		return bh;
1229 	}
1230 
1231 	if (bh_read(bh, 0) >= 0)
1232 		return bh;
1233 
1234 	brelse(bh);
1235 	*err = -EIO;
1236 	return NULL;
1237 }
1238 
1239 int udf_setsize(struct inode *inode, loff_t newsize)
1240 {
1241 	int err = 0;
1242 	struct udf_inode_info *iinfo;
1243 	unsigned int bsize = i_blocksize(inode);
1244 
1245 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1246 	      S_ISLNK(inode->i_mode)))
1247 		return -EINVAL;
1248 
1249 	iinfo = UDF_I(inode);
1250 	if (newsize > inode->i_size) {
1251 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1252 			if (bsize >=
1253 			    (udf_file_entry_alloc_offset(inode) + newsize)) {
1254 				down_write(&iinfo->i_data_sem);
1255 				iinfo->i_lenAlloc = newsize;
1256 				up_write(&iinfo->i_data_sem);
1257 				goto set_size;
1258 			}
1259 			err = udf_expand_file_adinicb(inode);
1260 			if (err)
1261 				return err;
1262 		}
1263 		err = udf_extend_file(inode, newsize);
1264 		if (err)
1265 			return err;
1266 set_size:
1267 		truncate_setsize(inode, newsize);
1268 	} else {
1269 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1270 			down_write(&iinfo->i_data_sem);
1271 			udf_clear_extent_cache(inode);
1272 			memset(iinfo->i_data + iinfo->i_lenEAttr + newsize,
1273 			       0x00, bsize - newsize -
1274 			       udf_file_entry_alloc_offset(inode));
1275 			iinfo->i_lenAlloc = newsize;
1276 			truncate_setsize(inode, newsize);
1277 			up_write(&iinfo->i_data_sem);
1278 			goto update_time;
1279 		}
1280 		err = block_truncate_page(inode->i_mapping, newsize,
1281 					  udf_get_block);
1282 		if (err)
1283 			return err;
1284 		truncate_setsize(inode, newsize);
1285 		down_write(&iinfo->i_data_sem);
1286 		udf_clear_extent_cache(inode);
1287 		err = udf_truncate_extents(inode);
1288 		up_write(&iinfo->i_data_sem);
1289 		if (err)
1290 			return err;
1291 	}
1292 update_time:
1293 	inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
1294 	if (IS_SYNC(inode))
1295 		udf_sync_inode(inode);
1296 	else
1297 		mark_inode_dirty(inode);
1298 	return err;
1299 }
1300 
1301 /*
1302  * Maximum length of linked list formed by ICB hierarchy. The chosen number is
1303  * arbitrary - just that we hopefully don't limit any real use of rewritten
1304  * inode on write-once media but avoid looping for too long on corrupted media.
1305  */
1306 #define UDF_MAX_ICB_NESTING 1024
1307 
1308 static int udf_read_inode(struct inode *inode, bool hidden_inode)
1309 {
1310 	struct buffer_head *bh = NULL;
1311 	struct fileEntry *fe;
1312 	struct extendedFileEntry *efe;
1313 	uint16_t ident;
1314 	struct udf_inode_info *iinfo = UDF_I(inode);
1315 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1316 	struct kernel_lb_addr *iloc = &iinfo->i_location;
1317 	unsigned int link_count;
1318 	unsigned int indirections = 0;
1319 	int bs = inode->i_sb->s_blocksize;
1320 	int ret = -EIO;
1321 	uint32_t uid, gid;
1322 	struct timespec64 ts;
1323 
1324 reread:
1325 	if (iloc->partitionReferenceNum >= sbi->s_partitions) {
1326 		udf_debug("partition reference: %u > logical volume partitions: %u\n",
1327 			  iloc->partitionReferenceNum, sbi->s_partitions);
1328 		return -EIO;
1329 	}
1330 
1331 	if (iloc->logicalBlockNum >=
1332 	    sbi->s_partmaps[iloc->partitionReferenceNum].s_partition_len) {
1333 		udf_debug("block=%u, partition=%u out of range\n",
1334 			  iloc->logicalBlockNum, iloc->partitionReferenceNum);
1335 		return -EIO;
1336 	}
1337 
1338 	/*
1339 	 * Set defaults, but the inode is still incomplete!
1340 	 * Note: get_new_inode() sets the following on a new inode:
1341 	 *      i_sb = sb
1342 	 *      i_no = ino
1343 	 *      i_flags = sb->s_flags
1344 	 *      i_state = 0
1345 	 * clean_inode(): zero fills and sets
1346 	 *      i_count = 1
1347 	 *      i_nlink = 1
1348 	 *      i_op = NULL;
1349 	 */
1350 	bh = udf_read_ptagged(inode->i_sb, iloc, 0, &ident);
1351 	if (!bh) {
1352 		udf_err(inode->i_sb, "(ino %lu) failed !bh\n", inode->i_ino);
1353 		return -EIO;
1354 	}
1355 
1356 	if (ident != TAG_IDENT_FE && ident != TAG_IDENT_EFE &&
1357 	    ident != TAG_IDENT_USE) {
1358 		udf_err(inode->i_sb, "(ino %lu) failed ident=%u\n",
1359 			inode->i_ino, ident);
1360 		goto out;
1361 	}
1362 
1363 	fe = (struct fileEntry *)bh->b_data;
1364 	efe = (struct extendedFileEntry *)bh->b_data;
1365 
1366 	if (fe->icbTag.strategyType == cpu_to_le16(4096)) {
1367 		struct buffer_head *ibh;
1368 
1369 		ibh = udf_read_ptagged(inode->i_sb, iloc, 1, &ident);
1370 		if (ident == TAG_IDENT_IE && ibh) {
1371 			struct kernel_lb_addr loc;
1372 			struct indirectEntry *ie;
1373 
1374 			ie = (struct indirectEntry *)ibh->b_data;
1375 			loc = lelb_to_cpu(ie->indirectICB.extLocation);
1376 
1377 			if (ie->indirectICB.extLength) {
1378 				brelse(ibh);
1379 				memcpy(&iinfo->i_location, &loc,
1380 				       sizeof(struct kernel_lb_addr));
1381 				if (++indirections > UDF_MAX_ICB_NESTING) {
1382 					udf_err(inode->i_sb,
1383 						"too many ICBs in ICB hierarchy"
1384 						" (max %d supported)\n",
1385 						UDF_MAX_ICB_NESTING);
1386 					goto out;
1387 				}
1388 				brelse(bh);
1389 				goto reread;
1390 			}
1391 		}
1392 		brelse(ibh);
1393 	} else if (fe->icbTag.strategyType != cpu_to_le16(4)) {
1394 		udf_err(inode->i_sb, "unsupported strategy type: %u\n",
1395 			le16_to_cpu(fe->icbTag.strategyType));
1396 		goto out;
1397 	}
1398 	if (fe->icbTag.strategyType == cpu_to_le16(4))
1399 		iinfo->i_strat4096 = 0;
1400 	else /* if (fe->icbTag.strategyType == cpu_to_le16(4096)) */
1401 		iinfo->i_strat4096 = 1;
1402 
1403 	iinfo->i_alloc_type = le16_to_cpu(fe->icbTag.flags) &
1404 							ICBTAG_FLAG_AD_MASK;
1405 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_SHORT &&
1406 	    iinfo->i_alloc_type != ICBTAG_FLAG_AD_LONG &&
1407 	    iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
1408 		ret = -EIO;
1409 		goto out;
1410 	}
1411 	iinfo->i_hidden = hidden_inode;
1412 	iinfo->i_unique = 0;
1413 	iinfo->i_lenEAttr = 0;
1414 	iinfo->i_lenExtents = 0;
1415 	iinfo->i_lenAlloc = 0;
1416 	iinfo->i_next_alloc_block = 0;
1417 	iinfo->i_next_alloc_goal = 0;
1418 	if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_EFE)) {
1419 		iinfo->i_efe = 1;
1420 		iinfo->i_use = 0;
1421 		ret = udf_alloc_i_data(inode, bs -
1422 					sizeof(struct extendedFileEntry));
1423 		if (ret)
1424 			goto out;
1425 		memcpy(iinfo->i_data,
1426 		       bh->b_data + sizeof(struct extendedFileEntry),
1427 		       bs - sizeof(struct extendedFileEntry));
1428 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_FE)) {
1429 		iinfo->i_efe = 0;
1430 		iinfo->i_use = 0;
1431 		ret = udf_alloc_i_data(inode, bs - sizeof(struct fileEntry));
1432 		if (ret)
1433 			goto out;
1434 		memcpy(iinfo->i_data,
1435 		       bh->b_data + sizeof(struct fileEntry),
1436 		       bs - sizeof(struct fileEntry));
1437 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_USE)) {
1438 		iinfo->i_efe = 0;
1439 		iinfo->i_use = 1;
1440 		iinfo->i_lenAlloc = le32_to_cpu(
1441 				((struct unallocSpaceEntry *)bh->b_data)->
1442 				 lengthAllocDescs);
1443 		ret = udf_alloc_i_data(inode, bs -
1444 					sizeof(struct unallocSpaceEntry));
1445 		if (ret)
1446 			goto out;
1447 		memcpy(iinfo->i_data,
1448 		       bh->b_data + sizeof(struct unallocSpaceEntry),
1449 		       bs - sizeof(struct unallocSpaceEntry));
1450 		return 0;
1451 	}
1452 
1453 	ret = -EIO;
1454 	read_lock(&sbi->s_cred_lock);
1455 	uid = le32_to_cpu(fe->uid);
1456 	if (uid == UDF_INVALID_ID ||
1457 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_SET))
1458 		inode->i_uid = sbi->s_uid;
1459 	else
1460 		i_uid_write(inode, uid);
1461 
1462 	gid = le32_to_cpu(fe->gid);
1463 	if (gid == UDF_INVALID_ID ||
1464 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_SET))
1465 		inode->i_gid = sbi->s_gid;
1466 	else
1467 		i_gid_write(inode, gid);
1468 
1469 	if (fe->icbTag.fileType != ICBTAG_FILE_TYPE_DIRECTORY &&
1470 			sbi->s_fmode != UDF_INVALID_MODE)
1471 		inode->i_mode = sbi->s_fmode;
1472 	else if (fe->icbTag.fileType == ICBTAG_FILE_TYPE_DIRECTORY &&
1473 			sbi->s_dmode != UDF_INVALID_MODE)
1474 		inode->i_mode = sbi->s_dmode;
1475 	else
1476 		inode->i_mode = udf_convert_permissions(fe);
1477 	inode->i_mode &= ~sbi->s_umask;
1478 	iinfo->i_extraPerms = le32_to_cpu(fe->permissions) & ~FE_MAPPED_PERMS;
1479 
1480 	read_unlock(&sbi->s_cred_lock);
1481 
1482 	link_count = le16_to_cpu(fe->fileLinkCount);
1483 	if (!link_count) {
1484 		if (!hidden_inode) {
1485 			ret = -ESTALE;
1486 			goto out;
1487 		}
1488 		link_count = 1;
1489 	}
1490 	set_nlink(inode, link_count);
1491 
1492 	inode->i_size = le64_to_cpu(fe->informationLength);
1493 	iinfo->i_lenExtents = inode->i_size;
1494 
1495 	if (iinfo->i_efe == 0) {
1496 		inode->i_blocks = le64_to_cpu(fe->logicalBlocksRecorded) <<
1497 			(inode->i_sb->s_blocksize_bits - 9);
1498 
1499 		udf_disk_stamp_to_time(&ts, fe->accessTime);
1500 		inode_set_atime_to_ts(inode, ts);
1501 		udf_disk_stamp_to_time(&ts, fe->modificationTime);
1502 		inode_set_mtime_to_ts(inode, ts);
1503 		udf_disk_stamp_to_time(&ts, fe->attrTime);
1504 		inode_set_ctime_to_ts(inode, ts);
1505 
1506 		iinfo->i_unique = le64_to_cpu(fe->uniqueID);
1507 		iinfo->i_lenEAttr = le32_to_cpu(fe->lengthExtendedAttr);
1508 		iinfo->i_lenAlloc = le32_to_cpu(fe->lengthAllocDescs);
1509 		iinfo->i_checkpoint = le32_to_cpu(fe->checkpoint);
1510 		iinfo->i_streamdir = 0;
1511 		iinfo->i_lenStreams = 0;
1512 	} else {
1513 		inode->i_blocks = le64_to_cpu(efe->logicalBlocksRecorded) <<
1514 		    (inode->i_sb->s_blocksize_bits - 9);
1515 
1516 		udf_disk_stamp_to_time(&ts, efe->accessTime);
1517 		inode_set_atime_to_ts(inode, ts);
1518 		udf_disk_stamp_to_time(&ts, efe->modificationTime);
1519 		inode_set_mtime_to_ts(inode, ts);
1520 		udf_disk_stamp_to_time(&ts, efe->attrTime);
1521 		inode_set_ctime_to_ts(inode, ts);
1522 		udf_disk_stamp_to_time(&iinfo->i_crtime, efe->createTime);
1523 
1524 		iinfo->i_unique = le64_to_cpu(efe->uniqueID);
1525 		iinfo->i_lenEAttr = le32_to_cpu(efe->lengthExtendedAttr);
1526 		iinfo->i_lenAlloc = le32_to_cpu(efe->lengthAllocDescs);
1527 		iinfo->i_checkpoint = le32_to_cpu(efe->checkpoint);
1528 
1529 		/* Named streams */
1530 		iinfo->i_streamdir = (efe->streamDirectoryICB.extLength != 0);
1531 		iinfo->i_locStreamdir =
1532 			lelb_to_cpu(efe->streamDirectoryICB.extLocation);
1533 		iinfo->i_lenStreams = le64_to_cpu(efe->objectSize);
1534 		if (iinfo->i_lenStreams >= inode->i_size)
1535 			iinfo->i_lenStreams -= inode->i_size;
1536 		else
1537 			iinfo->i_lenStreams = 0;
1538 	}
1539 	inode->i_generation = iinfo->i_unique;
1540 
1541 	/*
1542 	 * Sanity check length of allocation descriptors and extended attrs to
1543 	 * avoid integer overflows
1544 	 */
1545 	if (iinfo->i_lenEAttr > bs || iinfo->i_lenAlloc > bs)
1546 		goto out;
1547 	/* Now do exact checks */
1548 	if (udf_file_entry_alloc_offset(inode) + iinfo->i_lenAlloc > bs)
1549 		goto out;
1550 	/* Sanity checks for files in ICB so that we don't get confused later */
1551 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1552 		/*
1553 		 * For file in ICB data is stored in allocation descriptor
1554 		 * so sizes should match
1555 		 */
1556 		if (iinfo->i_lenAlloc != inode->i_size)
1557 			goto out;
1558 		/* File in ICB has to fit in there... */
1559 		if (inode->i_size > bs - udf_file_entry_alloc_offset(inode))
1560 			goto out;
1561 	}
1562 
1563 	switch (fe->icbTag.fileType) {
1564 	case ICBTAG_FILE_TYPE_DIRECTORY:
1565 		inode->i_op = &udf_dir_inode_operations;
1566 		inode->i_fop = &udf_dir_operations;
1567 		inode->i_mode |= S_IFDIR;
1568 		inc_nlink(inode);
1569 		break;
1570 	case ICBTAG_FILE_TYPE_REALTIME:
1571 	case ICBTAG_FILE_TYPE_REGULAR:
1572 	case ICBTAG_FILE_TYPE_UNDEF:
1573 	case ICBTAG_FILE_TYPE_VAT20:
1574 		inode->i_data.a_ops = &udf_aops;
1575 		inode->i_op = &udf_file_inode_operations;
1576 		inode->i_fop = &udf_file_operations;
1577 		inode->i_mode |= S_IFREG;
1578 		break;
1579 	case ICBTAG_FILE_TYPE_BLOCK:
1580 		inode->i_mode |= S_IFBLK;
1581 		break;
1582 	case ICBTAG_FILE_TYPE_CHAR:
1583 		inode->i_mode |= S_IFCHR;
1584 		break;
1585 	case ICBTAG_FILE_TYPE_FIFO:
1586 		init_special_inode(inode, inode->i_mode | S_IFIFO, 0);
1587 		break;
1588 	case ICBTAG_FILE_TYPE_SOCKET:
1589 		init_special_inode(inode, inode->i_mode | S_IFSOCK, 0);
1590 		break;
1591 	case ICBTAG_FILE_TYPE_SYMLINK:
1592 		inode->i_data.a_ops = &udf_symlink_aops;
1593 		inode->i_op = &udf_symlink_inode_operations;
1594 		inode_nohighmem(inode);
1595 		inode->i_mode = S_IFLNK | 0777;
1596 		break;
1597 	case ICBTAG_FILE_TYPE_MAIN:
1598 		udf_debug("METADATA FILE-----\n");
1599 		break;
1600 	case ICBTAG_FILE_TYPE_MIRROR:
1601 		udf_debug("METADATA MIRROR FILE-----\n");
1602 		break;
1603 	case ICBTAG_FILE_TYPE_BITMAP:
1604 		udf_debug("METADATA BITMAP FILE-----\n");
1605 		break;
1606 	default:
1607 		udf_err(inode->i_sb, "(ino %lu) failed unknown file type=%u\n",
1608 			inode->i_ino, fe->icbTag.fileType);
1609 		goto out;
1610 	}
1611 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1612 		struct deviceSpec *dsea =
1613 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1614 		if (dsea) {
1615 			init_special_inode(inode, inode->i_mode,
1616 				MKDEV(le32_to_cpu(dsea->majorDeviceIdent),
1617 				      le32_to_cpu(dsea->minorDeviceIdent)));
1618 			/* Developer ID ??? */
1619 		} else
1620 			goto out;
1621 	}
1622 	ret = 0;
1623 out:
1624 	brelse(bh);
1625 	return ret;
1626 }
1627 
1628 static int udf_alloc_i_data(struct inode *inode, size_t size)
1629 {
1630 	struct udf_inode_info *iinfo = UDF_I(inode);
1631 	iinfo->i_data = kmalloc(size, GFP_KERNEL);
1632 	if (!iinfo->i_data)
1633 		return -ENOMEM;
1634 	return 0;
1635 }
1636 
1637 static umode_t udf_convert_permissions(struct fileEntry *fe)
1638 {
1639 	umode_t mode;
1640 	uint32_t permissions;
1641 	uint32_t flags;
1642 
1643 	permissions = le32_to_cpu(fe->permissions);
1644 	flags = le16_to_cpu(fe->icbTag.flags);
1645 
1646 	mode =	((permissions) & 0007) |
1647 		((permissions >> 2) & 0070) |
1648 		((permissions >> 4) & 0700) |
1649 		((flags & ICBTAG_FLAG_SETUID) ? S_ISUID : 0) |
1650 		((flags & ICBTAG_FLAG_SETGID) ? S_ISGID : 0) |
1651 		((flags & ICBTAG_FLAG_STICKY) ? S_ISVTX : 0);
1652 
1653 	return mode;
1654 }
1655 
1656 void udf_update_extra_perms(struct inode *inode, umode_t mode)
1657 {
1658 	struct udf_inode_info *iinfo = UDF_I(inode);
1659 
1660 	/*
1661 	 * UDF 2.01 sec. 3.3.3.3 Note 2:
1662 	 * In Unix, delete permission tracks write
1663 	 */
1664 	iinfo->i_extraPerms &= ~FE_DELETE_PERMS;
1665 	if (mode & 0200)
1666 		iinfo->i_extraPerms |= FE_PERM_U_DELETE;
1667 	if (mode & 0020)
1668 		iinfo->i_extraPerms |= FE_PERM_G_DELETE;
1669 	if (mode & 0002)
1670 		iinfo->i_extraPerms |= FE_PERM_O_DELETE;
1671 }
1672 
1673 int udf_write_inode(struct inode *inode, struct writeback_control *wbc)
1674 {
1675 	return udf_update_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
1676 }
1677 
1678 static int udf_sync_inode(struct inode *inode)
1679 {
1680 	return udf_update_inode(inode, 1);
1681 }
1682 
1683 static void udf_adjust_time(struct udf_inode_info *iinfo, struct timespec64 time)
1684 {
1685 	if (iinfo->i_crtime.tv_sec > time.tv_sec ||
1686 	    (iinfo->i_crtime.tv_sec == time.tv_sec &&
1687 	     iinfo->i_crtime.tv_nsec > time.tv_nsec))
1688 		iinfo->i_crtime = time;
1689 }
1690 
1691 static int udf_update_inode(struct inode *inode, int do_sync)
1692 {
1693 	struct buffer_head *bh = NULL;
1694 	struct fileEntry *fe;
1695 	struct extendedFileEntry *efe;
1696 	uint64_t lb_recorded;
1697 	uint32_t udfperms;
1698 	uint16_t icbflags;
1699 	uint16_t crclen;
1700 	int err = 0;
1701 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1702 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1703 	struct udf_inode_info *iinfo = UDF_I(inode);
1704 
1705 	bh = sb_getblk(inode->i_sb,
1706 			udf_get_lb_pblock(inode->i_sb, &iinfo->i_location, 0));
1707 	if (!bh) {
1708 		udf_debug("getblk failure\n");
1709 		return -EIO;
1710 	}
1711 
1712 	lock_buffer(bh);
1713 	memset(bh->b_data, 0, inode->i_sb->s_blocksize);
1714 	fe = (struct fileEntry *)bh->b_data;
1715 	efe = (struct extendedFileEntry *)bh->b_data;
1716 
1717 	if (iinfo->i_use) {
1718 		struct unallocSpaceEntry *use =
1719 			(struct unallocSpaceEntry *)bh->b_data;
1720 
1721 		use->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1722 		memcpy(bh->b_data + sizeof(struct unallocSpaceEntry),
1723 		       iinfo->i_data, inode->i_sb->s_blocksize -
1724 					sizeof(struct unallocSpaceEntry));
1725 		use->descTag.tagIdent = cpu_to_le16(TAG_IDENT_USE);
1726 		crclen = sizeof(struct unallocSpaceEntry);
1727 
1728 		goto finish;
1729 	}
1730 
1731 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_FORGET))
1732 		fe->uid = cpu_to_le32(UDF_INVALID_ID);
1733 	else
1734 		fe->uid = cpu_to_le32(i_uid_read(inode));
1735 
1736 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_FORGET))
1737 		fe->gid = cpu_to_le32(UDF_INVALID_ID);
1738 	else
1739 		fe->gid = cpu_to_le32(i_gid_read(inode));
1740 
1741 	udfperms = ((inode->i_mode & 0007)) |
1742 		   ((inode->i_mode & 0070) << 2) |
1743 		   ((inode->i_mode & 0700) << 4);
1744 
1745 	udfperms |= iinfo->i_extraPerms;
1746 	fe->permissions = cpu_to_le32(udfperms);
1747 
1748 	if (S_ISDIR(inode->i_mode) && inode->i_nlink > 0)
1749 		fe->fileLinkCount = cpu_to_le16(inode->i_nlink - 1);
1750 	else {
1751 		if (iinfo->i_hidden)
1752 			fe->fileLinkCount = cpu_to_le16(0);
1753 		else
1754 			fe->fileLinkCount = cpu_to_le16(inode->i_nlink);
1755 	}
1756 
1757 	fe->informationLength = cpu_to_le64(inode->i_size);
1758 
1759 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1760 		struct regid *eid;
1761 		struct deviceSpec *dsea =
1762 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1763 		if (!dsea) {
1764 			dsea = (struct deviceSpec *)
1765 				udf_add_extendedattr(inode,
1766 						     sizeof(struct deviceSpec) +
1767 						     sizeof(struct regid), 12, 0x3);
1768 			dsea->attrType = cpu_to_le32(12);
1769 			dsea->attrSubtype = 1;
1770 			dsea->attrLength = cpu_to_le32(
1771 						sizeof(struct deviceSpec) +
1772 						sizeof(struct regid));
1773 			dsea->impUseLength = cpu_to_le32(sizeof(struct regid));
1774 		}
1775 		eid = (struct regid *)dsea->impUse;
1776 		memset(eid, 0, sizeof(*eid));
1777 		strcpy(eid->ident, UDF_ID_DEVELOPER);
1778 		eid->identSuffix[0] = UDF_OS_CLASS_UNIX;
1779 		eid->identSuffix[1] = UDF_OS_ID_LINUX;
1780 		dsea->majorDeviceIdent = cpu_to_le32(imajor(inode));
1781 		dsea->minorDeviceIdent = cpu_to_le32(iminor(inode));
1782 	}
1783 
1784 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1785 		lb_recorded = 0; /* No extents => no blocks! */
1786 	else
1787 		lb_recorded =
1788 			(inode->i_blocks + (1 << (blocksize_bits - 9)) - 1) >>
1789 			(blocksize_bits - 9);
1790 
1791 	if (iinfo->i_efe == 0) {
1792 		memcpy(bh->b_data + sizeof(struct fileEntry),
1793 		       iinfo->i_data,
1794 		       inode->i_sb->s_blocksize - sizeof(struct fileEntry));
1795 		fe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
1796 
1797 		udf_time_to_disk_stamp(&fe->accessTime, inode_get_atime(inode));
1798 		udf_time_to_disk_stamp(&fe->modificationTime, inode_get_mtime(inode));
1799 		udf_time_to_disk_stamp(&fe->attrTime, inode_get_ctime(inode));
1800 		memset(&(fe->impIdent), 0, sizeof(struct regid));
1801 		strcpy(fe->impIdent.ident, UDF_ID_DEVELOPER);
1802 		fe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1803 		fe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1804 		fe->uniqueID = cpu_to_le64(iinfo->i_unique);
1805 		fe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
1806 		fe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1807 		fe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
1808 		fe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_FE);
1809 		crclen = sizeof(struct fileEntry);
1810 	} else {
1811 		memcpy(bh->b_data + sizeof(struct extendedFileEntry),
1812 		       iinfo->i_data,
1813 		       inode->i_sb->s_blocksize -
1814 					sizeof(struct extendedFileEntry));
1815 		efe->objectSize =
1816 			cpu_to_le64(inode->i_size + iinfo->i_lenStreams);
1817 		efe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
1818 
1819 		if (iinfo->i_streamdir) {
1820 			struct long_ad *icb_lad = &efe->streamDirectoryICB;
1821 
1822 			icb_lad->extLocation =
1823 				cpu_to_lelb(iinfo->i_locStreamdir);
1824 			icb_lad->extLength =
1825 				cpu_to_le32(inode->i_sb->s_blocksize);
1826 		}
1827 
1828 		udf_adjust_time(iinfo, inode_get_atime(inode));
1829 		udf_adjust_time(iinfo, inode_get_mtime(inode));
1830 		udf_adjust_time(iinfo, inode_get_ctime(inode));
1831 
1832 		udf_time_to_disk_stamp(&efe->accessTime,
1833 				       inode_get_atime(inode));
1834 		udf_time_to_disk_stamp(&efe->modificationTime,
1835 				       inode_get_mtime(inode));
1836 		udf_time_to_disk_stamp(&efe->createTime, iinfo->i_crtime);
1837 		udf_time_to_disk_stamp(&efe->attrTime, inode_get_ctime(inode));
1838 
1839 		memset(&(efe->impIdent), 0, sizeof(efe->impIdent));
1840 		strcpy(efe->impIdent.ident, UDF_ID_DEVELOPER);
1841 		efe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1842 		efe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1843 		efe->uniqueID = cpu_to_le64(iinfo->i_unique);
1844 		efe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
1845 		efe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1846 		efe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
1847 		efe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EFE);
1848 		crclen = sizeof(struct extendedFileEntry);
1849 	}
1850 
1851 finish:
1852 	if (iinfo->i_strat4096) {
1853 		fe->icbTag.strategyType = cpu_to_le16(4096);
1854 		fe->icbTag.strategyParameter = cpu_to_le16(1);
1855 		fe->icbTag.numEntries = cpu_to_le16(2);
1856 	} else {
1857 		fe->icbTag.strategyType = cpu_to_le16(4);
1858 		fe->icbTag.numEntries = cpu_to_le16(1);
1859 	}
1860 
1861 	if (iinfo->i_use)
1862 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_USE;
1863 	else if (S_ISDIR(inode->i_mode))
1864 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_DIRECTORY;
1865 	else if (S_ISREG(inode->i_mode))
1866 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_REGULAR;
1867 	else if (S_ISLNK(inode->i_mode))
1868 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SYMLINK;
1869 	else if (S_ISBLK(inode->i_mode))
1870 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_BLOCK;
1871 	else if (S_ISCHR(inode->i_mode))
1872 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_CHAR;
1873 	else if (S_ISFIFO(inode->i_mode))
1874 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_FIFO;
1875 	else if (S_ISSOCK(inode->i_mode))
1876 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SOCKET;
1877 
1878 	icbflags =	iinfo->i_alloc_type |
1879 			((inode->i_mode & S_ISUID) ? ICBTAG_FLAG_SETUID : 0) |
1880 			((inode->i_mode & S_ISGID) ? ICBTAG_FLAG_SETGID : 0) |
1881 			((inode->i_mode & S_ISVTX) ? ICBTAG_FLAG_STICKY : 0) |
1882 			(le16_to_cpu(fe->icbTag.flags) &
1883 				~(ICBTAG_FLAG_AD_MASK | ICBTAG_FLAG_SETUID |
1884 				ICBTAG_FLAG_SETGID | ICBTAG_FLAG_STICKY));
1885 
1886 	fe->icbTag.flags = cpu_to_le16(icbflags);
1887 	if (sbi->s_udfrev >= 0x0200)
1888 		fe->descTag.descVersion = cpu_to_le16(3);
1889 	else
1890 		fe->descTag.descVersion = cpu_to_le16(2);
1891 	fe->descTag.tagSerialNum = cpu_to_le16(sbi->s_serial_number);
1892 	fe->descTag.tagLocation = cpu_to_le32(
1893 					iinfo->i_location.logicalBlockNum);
1894 	crclen += iinfo->i_lenEAttr + iinfo->i_lenAlloc - sizeof(struct tag);
1895 	fe->descTag.descCRCLength = cpu_to_le16(crclen);
1896 	fe->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)fe + sizeof(struct tag),
1897 						  crclen));
1898 	fe->descTag.tagChecksum = udf_tag_checksum(&fe->descTag);
1899 
1900 	set_buffer_uptodate(bh);
1901 	unlock_buffer(bh);
1902 
1903 	/* write the data blocks */
1904 	mark_buffer_dirty(bh);
1905 	if (do_sync) {
1906 		sync_dirty_buffer(bh);
1907 		if (buffer_write_io_error(bh)) {
1908 			udf_warn(inode->i_sb, "IO error syncing udf inode [%08lx]\n",
1909 				 inode->i_ino);
1910 			err = -EIO;
1911 		}
1912 	}
1913 	brelse(bh);
1914 
1915 	return err;
1916 }
1917 
1918 struct inode *__udf_iget(struct super_block *sb, struct kernel_lb_addr *ino,
1919 			 bool hidden_inode)
1920 {
1921 	unsigned long block = udf_get_lb_pblock(sb, ino, 0);
1922 	struct inode *inode = iget_locked(sb, block);
1923 	int err;
1924 
1925 	if (!inode)
1926 		return ERR_PTR(-ENOMEM);
1927 
1928 	if (!(inode->i_state & I_NEW)) {
1929 		if (UDF_I(inode)->i_hidden != hidden_inode) {
1930 			iput(inode);
1931 			return ERR_PTR(-EFSCORRUPTED);
1932 		}
1933 		return inode;
1934 	}
1935 
1936 	memcpy(&UDF_I(inode)->i_location, ino, sizeof(struct kernel_lb_addr));
1937 	err = udf_read_inode(inode, hidden_inode);
1938 	if (err < 0) {
1939 		iget_failed(inode);
1940 		return ERR_PTR(err);
1941 	}
1942 	unlock_new_inode(inode);
1943 
1944 	return inode;
1945 }
1946 
1947 int udf_setup_indirect_aext(struct inode *inode, udf_pblk_t block,
1948 			    struct extent_position *epos)
1949 {
1950 	struct super_block *sb = inode->i_sb;
1951 	struct buffer_head *bh;
1952 	struct allocExtDesc *aed;
1953 	struct extent_position nepos;
1954 	struct kernel_lb_addr neloc;
1955 	int ver, adsize;
1956 
1957 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
1958 		adsize = sizeof(struct short_ad);
1959 	else if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_LONG)
1960 		adsize = sizeof(struct long_ad);
1961 	else
1962 		return -EIO;
1963 
1964 	neloc.logicalBlockNum = block;
1965 	neloc.partitionReferenceNum = epos->block.partitionReferenceNum;
1966 
1967 	bh = sb_getblk(sb, udf_get_lb_pblock(sb, &neloc, 0));
1968 	if (!bh)
1969 		return -EIO;
1970 	lock_buffer(bh);
1971 	memset(bh->b_data, 0x00, sb->s_blocksize);
1972 	set_buffer_uptodate(bh);
1973 	unlock_buffer(bh);
1974 	mark_buffer_dirty_inode(bh, inode);
1975 
1976 	aed = (struct allocExtDesc *)(bh->b_data);
1977 	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT)) {
1978 		aed->previousAllocExtLocation =
1979 				cpu_to_le32(epos->block.logicalBlockNum);
1980 	}
1981 	aed->lengthAllocDescs = cpu_to_le32(0);
1982 	if (UDF_SB(sb)->s_udfrev >= 0x0200)
1983 		ver = 3;
1984 	else
1985 		ver = 2;
1986 	udf_new_tag(bh->b_data, TAG_IDENT_AED, ver, 1, block,
1987 		    sizeof(struct tag));
1988 
1989 	nepos.block = neloc;
1990 	nepos.offset = sizeof(struct allocExtDesc);
1991 	nepos.bh = bh;
1992 
1993 	/*
1994 	 * Do we have to copy current last extent to make space for indirect
1995 	 * one?
1996 	 */
1997 	if (epos->offset + adsize > sb->s_blocksize) {
1998 		struct kernel_lb_addr cp_loc;
1999 		uint32_t cp_len;
2000 		int cp_type;
2001 
2002 		epos->offset -= adsize;
2003 		cp_type = udf_current_aext(inode, epos, &cp_loc, &cp_len, 0);
2004 		cp_len |= ((uint32_t)cp_type) << 30;
2005 
2006 		__udf_add_aext(inode, &nepos, &cp_loc, cp_len, 1);
2007 		udf_write_aext(inode, epos, &nepos.block,
2008 			       sb->s_blocksize | EXT_NEXT_EXTENT_ALLOCDESCS, 0);
2009 	} else {
2010 		__udf_add_aext(inode, epos, &nepos.block,
2011 			       sb->s_blocksize | EXT_NEXT_EXTENT_ALLOCDESCS, 0);
2012 	}
2013 
2014 	brelse(epos->bh);
2015 	*epos = nepos;
2016 
2017 	return 0;
2018 }
2019 
2020 /*
2021  * Append extent at the given position - should be the first free one in inode
2022  * / indirect extent. This function assumes there is enough space in the inode
2023  * or indirect extent. Use udf_add_aext() if you didn't check for this before.
2024  */
2025 int __udf_add_aext(struct inode *inode, struct extent_position *epos,
2026 		   struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2027 {
2028 	struct udf_inode_info *iinfo = UDF_I(inode);
2029 	struct allocExtDesc *aed;
2030 	int adsize;
2031 
2032 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2033 		adsize = sizeof(struct short_ad);
2034 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2035 		adsize = sizeof(struct long_ad);
2036 	else
2037 		return -EIO;
2038 
2039 	if (!epos->bh) {
2040 		WARN_ON(iinfo->i_lenAlloc !=
2041 			epos->offset - udf_file_entry_alloc_offset(inode));
2042 	} else {
2043 		aed = (struct allocExtDesc *)epos->bh->b_data;
2044 		WARN_ON(le32_to_cpu(aed->lengthAllocDescs) !=
2045 			epos->offset - sizeof(struct allocExtDesc));
2046 		WARN_ON(epos->offset + adsize > inode->i_sb->s_blocksize);
2047 	}
2048 
2049 	udf_write_aext(inode, epos, eloc, elen, inc);
2050 
2051 	if (!epos->bh) {
2052 		iinfo->i_lenAlloc += adsize;
2053 		mark_inode_dirty(inode);
2054 	} else {
2055 		aed = (struct allocExtDesc *)epos->bh->b_data;
2056 		le32_add_cpu(&aed->lengthAllocDescs, adsize);
2057 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2058 				UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2059 			udf_update_tag(epos->bh->b_data,
2060 					epos->offset + (inc ? 0 : adsize));
2061 		else
2062 			udf_update_tag(epos->bh->b_data,
2063 					sizeof(struct allocExtDesc));
2064 		mark_buffer_dirty_inode(epos->bh, inode);
2065 	}
2066 
2067 	return 0;
2068 }
2069 
2070 /*
2071  * Append extent at given position - should be the first free one in inode
2072  * / indirect extent. Takes care of allocating and linking indirect blocks.
2073  */
2074 int udf_add_aext(struct inode *inode, struct extent_position *epos,
2075 		 struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2076 {
2077 	int adsize;
2078 	struct super_block *sb = inode->i_sb;
2079 
2080 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2081 		adsize = sizeof(struct short_ad);
2082 	else if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2083 		adsize = sizeof(struct long_ad);
2084 	else
2085 		return -EIO;
2086 
2087 	if (epos->offset + (2 * adsize) > sb->s_blocksize) {
2088 		int err;
2089 		udf_pblk_t new_block;
2090 
2091 		new_block = udf_new_block(sb, NULL,
2092 					  epos->block.partitionReferenceNum,
2093 					  epos->block.logicalBlockNum, &err);
2094 		if (!new_block)
2095 			return -ENOSPC;
2096 
2097 		err = udf_setup_indirect_aext(inode, new_block, epos);
2098 		if (err)
2099 			return err;
2100 	}
2101 
2102 	return __udf_add_aext(inode, epos, eloc, elen, inc);
2103 }
2104 
2105 void udf_write_aext(struct inode *inode, struct extent_position *epos,
2106 		    struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2107 {
2108 	int adsize;
2109 	uint8_t *ptr;
2110 	struct short_ad *sad;
2111 	struct long_ad *lad;
2112 	struct udf_inode_info *iinfo = UDF_I(inode);
2113 
2114 	if (!epos->bh)
2115 		ptr = iinfo->i_data + epos->offset -
2116 			udf_file_entry_alloc_offset(inode) +
2117 			iinfo->i_lenEAttr;
2118 	else
2119 		ptr = epos->bh->b_data + epos->offset;
2120 
2121 	switch (iinfo->i_alloc_type) {
2122 	case ICBTAG_FLAG_AD_SHORT:
2123 		sad = (struct short_ad *)ptr;
2124 		sad->extLength = cpu_to_le32(elen);
2125 		sad->extPosition = cpu_to_le32(eloc->logicalBlockNum);
2126 		adsize = sizeof(struct short_ad);
2127 		break;
2128 	case ICBTAG_FLAG_AD_LONG:
2129 		lad = (struct long_ad *)ptr;
2130 		lad->extLength = cpu_to_le32(elen);
2131 		lad->extLocation = cpu_to_lelb(*eloc);
2132 		memset(lad->impUse, 0x00, sizeof(lad->impUse));
2133 		adsize = sizeof(struct long_ad);
2134 		break;
2135 	default:
2136 		return;
2137 	}
2138 
2139 	if (epos->bh) {
2140 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2141 		    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201) {
2142 			struct allocExtDesc *aed =
2143 				(struct allocExtDesc *)epos->bh->b_data;
2144 			udf_update_tag(epos->bh->b_data,
2145 				       le32_to_cpu(aed->lengthAllocDescs) +
2146 				       sizeof(struct allocExtDesc));
2147 		}
2148 		mark_buffer_dirty_inode(epos->bh, inode);
2149 	} else {
2150 		mark_inode_dirty(inode);
2151 	}
2152 
2153 	if (inc)
2154 		epos->offset += adsize;
2155 }
2156 
2157 /*
2158  * Only 1 indirect extent in a row really makes sense but allow upto 16 in case
2159  * someone does some weird stuff.
2160  */
2161 #define UDF_MAX_INDIR_EXTS 16
2162 
2163 int8_t udf_next_aext(struct inode *inode, struct extent_position *epos,
2164 		     struct kernel_lb_addr *eloc, uint32_t *elen, int inc)
2165 {
2166 	int8_t etype;
2167 	unsigned int indirections = 0;
2168 
2169 	while ((etype = udf_current_aext(inode, epos, eloc, elen, inc)) ==
2170 	       (EXT_NEXT_EXTENT_ALLOCDESCS >> 30)) {
2171 		udf_pblk_t block;
2172 
2173 		if (++indirections > UDF_MAX_INDIR_EXTS) {
2174 			udf_err(inode->i_sb,
2175 				"too many indirect extents in inode %lu\n",
2176 				inode->i_ino);
2177 			return -1;
2178 		}
2179 
2180 		epos->block = *eloc;
2181 		epos->offset = sizeof(struct allocExtDesc);
2182 		brelse(epos->bh);
2183 		block = udf_get_lb_pblock(inode->i_sb, &epos->block, 0);
2184 		epos->bh = sb_bread(inode->i_sb, block);
2185 		if (!epos->bh) {
2186 			udf_debug("reading block %u failed!\n", block);
2187 			return -1;
2188 		}
2189 	}
2190 
2191 	return etype;
2192 }
2193 
2194 int8_t udf_current_aext(struct inode *inode, struct extent_position *epos,
2195 			struct kernel_lb_addr *eloc, uint32_t *elen, int inc)
2196 {
2197 	int alen;
2198 	int8_t etype;
2199 	uint8_t *ptr;
2200 	struct short_ad *sad;
2201 	struct long_ad *lad;
2202 	struct udf_inode_info *iinfo = UDF_I(inode);
2203 
2204 	if (!epos->bh) {
2205 		if (!epos->offset)
2206 			epos->offset = udf_file_entry_alloc_offset(inode);
2207 		ptr = iinfo->i_data + epos->offset -
2208 			udf_file_entry_alloc_offset(inode) +
2209 			iinfo->i_lenEAttr;
2210 		alen = udf_file_entry_alloc_offset(inode) +
2211 							iinfo->i_lenAlloc;
2212 	} else {
2213 		if (!epos->offset)
2214 			epos->offset = sizeof(struct allocExtDesc);
2215 		ptr = epos->bh->b_data + epos->offset;
2216 		alen = sizeof(struct allocExtDesc) +
2217 			le32_to_cpu(((struct allocExtDesc *)epos->bh->b_data)->
2218 							lengthAllocDescs);
2219 	}
2220 
2221 	switch (iinfo->i_alloc_type) {
2222 	case ICBTAG_FLAG_AD_SHORT:
2223 		sad = udf_get_fileshortad(ptr, alen, &epos->offset, inc);
2224 		if (!sad)
2225 			return -1;
2226 		etype = le32_to_cpu(sad->extLength) >> 30;
2227 		eloc->logicalBlockNum = le32_to_cpu(sad->extPosition);
2228 		eloc->partitionReferenceNum =
2229 				iinfo->i_location.partitionReferenceNum;
2230 		*elen = le32_to_cpu(sad->extLength) & UDF_EXTENT_LENGTH_MASK;
2231 		break;
2232 	case ICBTAG_FLAG_AD_LONG:
2233 		lad = udf_get_filelongad(ptr, alen, &epos->offset, inc);
2234 		if (!lad)
2235 			return -1;
2236 		etype = le32_to_cpu(lad->extLength) >> 30;
2237 		*eloc = lelb_to_cpu(lad->extLocation);
2238 		*elen = le32_to_cpu(lad->extLength) & UDF_EXTENT_LENGTH_MASK;
2239 		break;
2240 	default:
2241 		udf_debug("alloc_type = %u unsupported\n", iinfo->i_alloc_type);
2242 		return -1;
2243 	}
2244 
2245 	return etype;
2246 }
2247 
2248 static int udf_insert_aext(struct inode *inode, struct extent_position epos,
2249 			   struct kernel_lb_addr neloc, uint32_t nelen)
2250 {
2251 	struct kernel_lb_addr oeloc;
2252 	uint32_t oelen;
2253 	int8_t etype;
2254 	int err;
2255 
2256 	if (epos.bh)
2257 		get_bh(epos.bh);
2258 
2259 	while ((etype = udf_next_aext(inode, &epos, &oeloc, &oelen, 0)) != -1) {
2260 		udf_write_aext(inode, &epos, &neloc, nelen, 1);
2261 		neloc = oeloc;
2262 		nelen = (etype << 30) | oelen;
2263 	}
2264 	err = udf_add_aext(inode, &epos, &neloc, nelen, 1);
2265 	brelse(epos.bh);
2266 
2267 	return err;
2268 }
2269 
2270 int8_t udf_delete_aext(struct inode *inode, struct extent_position epos)
2271 {
2272 	struct extent_position oepos;
2273 	int adsize;
2274 	int8_t etype;
2275 	struct allocExtDesc *aed;
2276 	struct udf_inode_info *iinfo;
2277 	struct kernel_lb_addr eloc;
2278 	uint32_t elen;
2279 
2280 	if (epos.bh) {
2281 		get_bh(epos.bh);
2282 		get_bh(epos.bh);
2283 	}
2284 
2285 	iinfo = UDF_I(inode);
2286 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2287 		adsize = sizeof(struct short_ad);
2288 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2289 		adsize = sizeof(struct long_ad);
2290 	else
2291 		adsize = 0;
2292 
2293 	oepos = epos;
2294 	if (udf_next_aext(inode, &epos, &eloc, &elen, 1) == -1)
2295 		return -1;
2296 
2297 	while ((etype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1) {
2298 		udf_write_aext(inode, &oepos, &eloc, (etype << 30) | elen, 1);
2299 		if (oepos.bh != epos.bh) {
2300 			oepos.block = epos.block;
2301 			brelse(oepos.bh);
2302 			get_bh(epos.bh);
2303 			oepos.bh = epos.bh;
2304 			oepos.offset = epos.offset - adsize;
2305 		}
2306 	}
2307 	memset(&eloc, 0x00, sizeof(struct kernel_lb_addr));
2308 	elen = 0;
2309 
2310 	if (epos.bh != oepos.bh) {
2311 		udf_free_blocks(inode->i_sb, inode, &epos.block, 0, 1);
2312 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2313 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2314 		if (!oepos.bh) {
2315 			iinfo->i_lenAlloc -= (adsize * 2);
2316 			mark_inode_dirty(inode);
2317 		} else {
2318 			aed = (struct allocExtDesc *)oepos.bh->b_data;
2319 			le32_add_cpu(&aed->lengthAllocDescs, -(2 * adsize));
2320 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2321 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2322 				udf_update_tag(oepos.bh->b_data,
2323 						oepos.offset - (2 * adsize));
2324 			else
2325 				udf_update_tag(oepos.bh->b_data,
2326 						sizeof(struct allocExtDesc));
2327 			mark_buffer_dirty_inode(oepos.bh, inode);
2328 		}
2329 	} else {
2330 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2331 		if (!oepos.bh) {
2332 			iinfo->i_lenAlloc -= adsize;
2333 			mark_inode_dirty(inode);
2334 		} else {
2335 			aed = (struct allocExtDesc *)oepos.bh->b_data;
2336 			le32_add_cpu(&aed->lengthAllocDescs, -adsize);
2337 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2338 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2339 				udf_update_tag(oepos.bh->b_data,
2340 						epos.offset - adsize);
2341 			else
2342 				udf_update_tag(oepos.bh->b_data,
2343 						sizeof(struct allocExtDesc));
2344 			mark_buffer_dirty_inode(oepos.bh, inode);
2345 		}
2346 	}
2347 
2348 	brelse(epos.bh);
2349 	brelse(oepos.bh);
2350 
2351 	return (elen >> 30);
2352 }
2353 
2354 int8_t inode_bmap(struct inode *inode, sector_t block,
2355 		  struct extent_position *pos, struct kernel_lb_addr *eloc,
2356 		  uint32_t *elen, sector_t *offset)
2357 {
2358 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
2359 	loff_t lbcount = 0, bcount = (loff_t) block << blocksize_bits;
2360 	int8_t etype;
2361 	struct udf_inode_info *iinfo;
2362 
2363 	iinfo = UDF_I(inode);
2364 	if (!udf_read_extent_cache(inode, bcount, &lbcount, pos)) {
2365 		pos->offset = 0;
2366 		pos->block = iinfo->i_location;
2367 		pos->bh = NULL;
2368 	}
2369 	*elen = 0;
2370 	do {
2371 		etype = udf_next_aext(inode, pos, eloc, elen, 1);
2372 		if (etype == -1) {
2373 			*offset = (bcount - lbcount) >> blocksize_bits;
2374 			iinfo->i_lenExtents = lbcount;
2375 			return -1;
2376 		}
2377 		lbcount += *elen;
2378 	} while (lbcount <= bcount);
2379 	/* update extent cache */
2380 	udf_update_extent_cache(inode, lbcount - *elen, pos);
2381 	*offset = (bcount + *elen - lbcount) >> blocksize_bits;
2382 
2383 	return etype;
2384 }
2385