xref: /linux/fs/udf/inode.c (revision f4cdf7ca9a1fdcca413157df19753f388a5a224e)
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_alloc_i_data(struct inode *inode, size_t size);
55 static int inode_getblk(struct inode *inode, struct udf_map_rq *map);
56 static int udf_insert_aext(struct inode *, struct extent_position,
57 			   struct kernel_lb_addr, uint32_t);
58 static void udf_split_extents(struct inode *, int *, int, udf_pblk_t,
59 			      struct kernel_long_ad *, int *);
60 static void udf_prealloc_extents(struct inode *, int, int,
61 				 struct kernel_long_ad *, int *);
62 static void udf_merge_extents(struct inode *, struct kernel_long_ad *, int *);
63 static int udf_update_extents(struct inode *, struct kernel_long_ad *, int,
64 			      int, struct extent_position *);
65 static int udf_get_block_wb(struct inode *inode, sector_t block,
66 			    struct buffer_head *bh_result, int create);
67 
68 static void __udf_clear_extent_cache(struct inode *inode)
69 {
70 	struct udf_inode_info *iinfo = UDF_I(inode);
71 
72 	if (iinfo->cached_extent.lstart != -1) {
73 		brelse(iinfo->cached_extent.epos.bh);
74 		iinfo->cached_extent.lstart = -1;
75 	}
76 }
77 
78 /* Invalidate extent cache */
79 static void udf_clear_extent_cache(struct inode *inode)
80 {
81 	struct udf_inode_info *iinfo = UDF_I(inode);
82 
83 	spin_lock(&iinfo->i_extent_cache_lock);
84 	__udf_clear_extent_cache(inode);
85 	spin_unlock(&iinfo->i_extent_cache_lock);
86 }
87 
88 /* Return contents of extent cache */
89 static int udf_read_extent_cache(struct inode *inode, loff_t bcount,
90 				 loff_t *lbcount, struct extent_position *pos)
91 {
92 	struct udf_inode_info *iinfo = UDF_I(inode);
93 	int ret = 0;
94 
95 	spin_lock(&iinfo->i_extent_cache_lock);
96 	if ((iinfo->cached_extent.lstart <= bcount) &&
97 	    (iinfo->cached_extent.lstart != -1)) {
98 		/* Cache hit */
99 		*lbcount = iinfo->cached_extent.lstart;
100 		memcpy(pos, &iinfo->cached_extent.epos,
101 		       sizeof(struct extent_position));
102 		if (pos->bh)
103 			get_bh(pos->bh);
104 		ret = 1;
105 	}
106 	spin_unlock(&iinfo->i_extent_cache_lock);
107 	return ret;
108 }
109 
110 /* Add extent to extent cache */
111 static void udf_update_extent_cache(struct inode *inode, loff_t estart,
112 				    struct extent_position *pos)
113 {
114 	struct udf_inode_info *iinfo = UDF_I(inode);
115 
116 	spin_lock(&iinfo->i_extent_cache_lock);
117 	/* Invalidate previously cached extent */
118 	__udf_clear_extent_cache(inode);
119 	if (pos->bh)
120 		get_bh(pos->bh);
121 	memcpy(&iinfo->cached_extent.epos, pos, sizeof(*pos));
122 	iinfo->cached_extent.lstart = estart;
123 	switch (iinfo->i_alloc_type) {
124 	case ICBTAG_FLAG_AD_SHORT:
125 		iinfo->cached_extent.epos.offset -= sizeof(struct short_ad);
126 		break;
127 	case ICBTAG_FLAG_AD_LONG:
128 		iinfo->cached_extent.epos.offset -= sizeof(struct long_ad);
129 		break;
130 	}
131 	spin_unlock(&iinfo->i_extent_cache_lock);
132 }
133 
134 void udf_evict_inode(struct inode *inode)
135 {
136 	struct udf_inode_info *iinfo = UDF_I(inode);
137 	int want_delete = 0;
138 
139 	if (!is_bad_inode(inode)) {
140 		if (!inode->i_nlink) {
141 			want_delete = 1;
142 			udf_setsize(inode, 0);
143 			sync_inode_metadata(inode, IS_SYNC(inode));
144 		}
145 		if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB &&
146 		    inode->i_size != iinfo->i_lenExtents) {
147 			udf_warn(inode->i_sb,
148 				 "Inode %llu (mode %o) has inode size %llu different from extent length %llu. Filesystem need not be standards compliant.\n",
149 				 inode->i_ino, inode->i_mode,
150 				 (unsigned long long)inode->i_size,
151 				 (unsigned long long)iinfo->i_lenExtents);
152 		}
153 	}
154 	truncate_inode_pages_final(&inode->i_data);
155 	if (!want_delete)
156 		mmb_sync(&iinfo->i_metadata_bhs);
157 	mmb_invalidate(&iinfo->i_metadata_bhs);
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_handle_page_wb(struct folio *folio,
185 			      struct writeback_control *wbc)
186 {
187 	struct inode *inode = folio->mapping->host;
188 	struct udf_inode_info *iinfo = UDF_I(inode);
189 
190 	/*
191 	 * Inodes in the normal format are handled by the generic code. This
192 	 * check is race-free as the folio lock protects us from inode type
193 	 * conversion.
194 	 */
195 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB)
196 		return 1;
197 
198 	memcpy_from_file_folio(iinfo->i_data + iinfo->i_lenEAttr, folio,
199 				0, i_size_read(inode));
200 	folio_unlock(folio);
201 	mark_inode_dirty(inode);
202 	return 0;
203 }
204 
205 static int udf_writepages(struct address_space *mapping,
206 			  struct writeback_control *wbc)
207 {
208 	return __mpage_writepages(mapping, wbc, udf_get_block_wb,
209 				  udf_handle_page_wb);
210 }
211 
212 static void udf_adinicb_read_folio(struct folio *folio)
213 {
214 	struct inode *inode = folio->mapping->host;
215 	struct udf_inode_info *iinfo = UDF_I(inode);
216 	loff_t isize = i_size_read(inode);
217 
218 	folio_fill_tail(folio, 0, iinfo->i_data + iinfo->i_lenEAttr, isize);
219 	folio_mark_uptodate(folio);
220 }
221 
222 static int udf_read_folio(struct file *file, struct folio *folio)
223 {
224 	struct udf_inode_info *iinfo = UDF_I(file_inode(file));
225 
226 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
227 		udf_adinicb_read_folio(folio);
228 		folio_unlock(folio);
229 		return 0;
230 	}
231 	return mpage_read_folio(folio, udf_get_block);
232 }
233 
234 static void udf_readahead(struct readahead_control *rac)
235 {
236 	struct udf_inode_info *iinfo = UDF_I(rac->mapping->host);
237 
238 	/*
239 	 * No readahead needed for in-ICB files and udf_get_block() would get
240 	 * confused for such file anyway.
241 	 */
242 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
243 		return;
244 
245 	mpage_readahead(rac, udf_get_block);
246 }
247 
248 static int udf_write_begin(const struct kiocb *iocb,
249 			   struct address_space *mapping,
250 			   loff_t pos, unsigned len,
251 			   struct folio **foliop, void **fsdata)
252 {
253 	struct file *file = iocb->ki_filp;
254 	struct udf_inode_info *iinfo = UDF_I(file_inode(file));
255 	struct folio *folio;
256 	int ret;
257 
258 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
259 		ret = block_write_begin(mapping, pos, len, foliop,
260 					udf_get_block);
261 		if (unlikely(ret))
262 			udf_write_failed(mapping, pos + len);
263 		return ret;
264 	}
265 	if (WARN_ON_ONCE(pos >= PAGE_SIZE))
266 		return -EIO;
267 	folio = __filemap_get_folio(mapping, 0, FGP_WRITEBEGIN,
268 			mapping_gfp_mask(mapping));
269 	if (IS_ERR(folio))
270 		return PTR_ERR(folio);
271 	*foliop = folio;
272 	if (!folio_test_uptodate(folio))
273 		udf_adinicb_read_folio(folio);
274 	return 0;
275 }
276 
277 static int udf_write_end(const struct kiocb *iocb,
278 			 struct address_space *mapping,
279 			 loff_t pos, unsigned len, unsigned copied,
280 			 struct folio *folio, void *fsdata)
281 {
282 	struct inode *inode = file_inode(iocb->ki_filp);
283 	loff_t last_pos;
284 
285 	if (UDF_I(inode)->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB)
286 		return generic_write_end(iocb, mapping, pos, len, copied, folio,
287 					 fsdata);
288 	last_pos = pos + copied;
289 	if (last_pos > inode->i_size)
290 		i_size_write(inode, last_pos);
291 	folio_mark_dirty(folio);
292 	folio_unlock(folio);
293 	folio_put(folio);
294 
295 	return copied;
296 }
297 
298 static ssize_t udf_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
299 {
300 	struct file *file = iocb->ki_filp;
301 	struct address_space *mapping = file->f_mapping;
302 	struct inode *inode = mapping->host;
303 	size_t count = iov_iter_count(iter);
304 	ssize_t ret;
305 
306 	/* Fallback to buffered IO for in-ICB files */
307 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
308 		return 0;
309 	ret = blockdev_direct_IO(iocb, inode, iter, udf_get_block);
310 	if (unlikely(ret < 0 && iov_iter_rw(iter) == WRITE))
311 		udf_write_failed(mapping, iocb->ki_pos + count);
312 	return ret;
313 }
314 
315 static sector_t udf_bmap(struct address_space *mapping, sector_t block)
316 {
317 	struct udf_inode_info *iinfo = UDF_I(mapping->host);
318 
319 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
320 		return -EINVAL;
321 	return generic_block_bmap(mapping, block, udf_get_block);
322 }
323 
324 const struct address_space_operations udf_aops = {
325 	.dirty_folio	= block_dirty_folio,
326 	.invalidate_folio = block_invalidate_folio,
327 	.read_folio	= udf_read_folio,
328 	.readahead	= udf_readahead,
329 	.writepages	= udf_writepages,
330 	.write_begin	= udf_write_begin,
331 	.write_end	= udf_write_end,
332 	.direct_IO	= udf_direct_IO,
333 	.bmap		= udf_bmap,
334 	.migrate_folio	= buffer_migrate_folio,
335 };
336 
337 /*
338  * Expand file stored in ICB to a normal one-block-file
339  *
340  * This function requires i_mutex held
341  */
342 int udf_expand_file_adinicb(struct inode *inode)
343 {
344 	struct folio *folio;
345 	struct udf_inode_info *iinfo = UDF_I(inode);
346 	int err;
347 
348 	WARN_ON_ONCE(!inode_is_locked(inode));
349 	if (!iinfo->i_lenAlloc) {
350 		down_write(&iinfo->i_data_sem);
351 		if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
352 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
353 		else
354 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
355 		up_write(&iinfo->i_data_sem);
356 		mark_inode_dirty(inode);
357 		return 0;
358 	}
359 
360 	folio = __filemap_get_folio(inode->i_mapping, 0,
361 			FGP_LOCK | FGP_ACCESSED | FGP_CREAT, GFP_KERNEL);
362 	if (IS_ERR(folio))
363 		return PTR_ERR(folio);
364 
365 	if (!folio_test_uptodate(folio))
366 		udf_adinicb_read_folio(folio);
367 	down_write(&iinfo->i_data_sem);
368 	memset(iinfo->i_data + iinfo->i_lenEAttr, 0x00,
369 	       iinfo->i_lenAlloc);
370 	iinfo->i_lenAlloc = 0;
371 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
372 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
373 	else
374 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
375 	folio_mark_dirty(folio);
376 	folio_unlock(folio);
377 	up_write(&iinfo->i_data_sem);
378 	err = filemap_fdatawrite(inode->i_mapping);
379 	if (err) {
380 		/* Restore everything back so that we don't lose data... */
381 		folio_lock(folio);
382 		down_write(&iinfo->i_data_sem);
383 		memcpy_from_folio(iinfo->i_data + iinfo->i_lenEAttr,
384 				folio, 0, inode->i_size);
385 		folio_unlock(folio);
386 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
387 		iinfo->i_lenAlloc = inode->i_size;
388 		up_write(&iinfo->i_data_sem);
389 	}
390 	folio_put(folio);
391 	mark_inode_dirty(inode);
392 
393 	return err;
394 }
395 
396 #define UDF_MAP_CREATE		0x01	/* Mapping can allocate new blocks */
397 #define UDF_MAP_NOPREALLOC	0x02	/* Do not preallocate blocks */
398 
399 #define UDF_BLK_MAPPED	0x01	/* Block was successfully mapped */
400 #define UDF_BLK_NEW	0x02	/* Block was freshly allocated */
401 
402 struct udf_map_rq {
403 	sector_t lblk;
404 	udf_pblk_t pblk;
405 	int iflags;		/* UDF_MAP_ flags determining behavior */
406 	int oflags;		/* UDF_BLK_ flags reporting results */
407 };
408 
409 static int udf_map_block(struct inode *inode, struct udf_map_rq *map)
410 {
411 	int ret;
412 	struct udf_inode_info *iinfo = UDF_I(inode);
413 
414 	if (WARN_ON_ONCE(iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB))
415 		return -EFSCORRUPTED;
416 
417 	map->oflags = 0;
418 	if (!(map->iflags & UDF_MAP_CREATE)) {
419 		struct kernel_lb_addr eloc;
420 		uint32_t elen;
421 		sector_t offset;
422 		struct extent_position epos = {};
423 		int8_t etype;
424 
425 		down_read(&iinfo->i_data_sem);
426 		ret = inode_bmap(inode, map->lblk, &epos, &eloc, &elen, &offset,
427 				 &etype);
428 		if (ret < 0)
429 			goto out_read;
430 		if (ret > 0 && etype == (EXT_RECORDED_ALLOCATED >> 30)) {
431 			map->pblk = udf_get_lb_pblock(inode->i_sb, &eloc,
432 							offset);
433 			map->oflags |= UDF_BLK_MAPPED;
434 			ret = 0;
435 		}
436 out_read:
437 		up_read(&iinfo->i_data_sem);
438 		brelse(epos.bh);
439 
440 		return ret;
441 	}
442 
443 	down_write(&iinfo->i_data_sem);
444 	/*
445 	 * Block beyond EOF and prealloc extents? Just discard preallocation
446 	 * as it is not useful and complicates things.
447 	 */
448 	if (((loff_t)map->lblk) << inode->i_blkbits >= iinfo->i_lenExtents)
449 		udf_discard_prealloc(inode);
450 	udf_clear_extent_cache(inode);
451 	ret = inode_getblk(inode, map);
452 	up_write(&iinfo->i_data_sem);
453 	return ret;
454 }
455 
456 static int __udf_get_block(struct inode *inode, sector_t block,
457 			   struct buffer_head *bh_result, int flags)
458 {
459 	int err;
460 	struct udf_map_rq map = {
461 		.lblk = block,
462 		.iflags = flags,
463 	};
464 
465 	err = udf_map_block(inode, &map);
466 	if (err < 0)
467 		return err;
468 	if (map.oflags & UDF_BLK_MAPPED) {
469 		map_bh(bh_result, inode->i_sb, map.pblk);
470 		if (map.oflags & UDF_BLK_NEW)
471 			set_buffer_new(bh_result);
472 	}
473 	return 0;
474 }
475 
476 int udf_get_block(struct inode *inode, sector_t block,
477 		  struct buffer_head *bh_result, int create)
478 {
479 	int flags = create ? UDF_MAP_CREATE : 0;
480 
481 	/*
482 	 * We preallocate blocks only for regular files. It also makes sense
483 	 * for directories but there's a problem when to drop the
484 	 * preallocation. We might use some delayed work for that but I feel
485 	 * it's overengineering for a filesystem like UDF.
486 	 */
487 	if (!S_ISREG(inode->i_mode))
488 		flags |= UDF_MAP_NOPREALLOC;
489 	return __udf_get_block(inode, block, bh_result, flags);
490 }
491 
492 /*
493  * We shouldn't be allocating blocks on page writeback since we allocate them
494  * on page fault. We can spot dirty buffers without allocated blocks though
495  * when truncate expands file. These however don't have valid data so we can
496  * safely ignore them. So never allocate blocks from page writeback.
497  */
498 static int udf_get_block_wb(struct inode *inode, sector_t block,
499 			    struct buffer_head *bh_result, int create)
500 {
501 	return __udf_get_block(inode, block, bh_result, 0);
502 }
503 
504 /* Extend the file with new blocks totaling 'new_block_bytes',
505  * return the number of extents added
506  */
507 static int udf_do_extend_file(struct inode *inode,
508 			      struct extent_position *last_pos,
509 			      struct kernel_long_ad *last_ext,
510 			      loff_t new_block_bytes)
511 {
512 	uint32_t add;
513 	int count = 0, fake = !(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
514 	struct super_block *sb = inode->i_sb;
515 	struct udf_inode_info *iinfo;
516 	int err;
517 
518 	/* The previous extent is fake and we should not extend by anything
519 	 * - there's nothing to do... */
520 	if (!new_block_bytes && fake)
521 		return 0;
522 
523 	iinfo = UDF_I(inode);
524 	/* Round the last extent up to a multiple of block size */
525 	if (last_ext->extLength & (sb->s_blocksize - 1)) {
526 		last_ext->extLength =
527 			(last_ext->extLength & UDF_EXTENT_FLAG_MASK) |
528 			(((last_ext->extLength & UDF_EXTENT_LENGTH_MASK) +
529 			  sb->s_blocksize - 1) & ~(sb->s_blocksize - 1));
530 		iinfo->i_lenExtents =
531 			(iinfo->i_lenExtents + sb->s_blocksize - 1) &
532 			~(sb->s_blocksize - 1);
533 	}
534 
535 	add = 0;
536 	/* Can we merge with the previous extent? */
537 	if ((last_ext->extLength & UDF_EXTENT_FLAG_MASK) ==
538 					EXT_NOT_RECORDED_NOT_ALLOCATED) {
539 		add = (1 << 30) - sb->s_blocksize -
540 			(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
541 		if (add > new_block_bytes)
542 			add = new_block_bytes;
543 		new_block_bytes -= add;
544 		last_ext->extLength += add;
545 	}
546 
547 	if (fake) {
548 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
549 				   last_ext->extLength, 1);
550 		if (err < 0)
551 			goto out_err;
552 		count++;
553 	} else {
554 		struct kernel_lb_addr tmploc;
555 		uint32_t tmplen;
556 		int8_t tmptype;
557 
558 		udf_write_aext(inode, last_pos, &last_ext->extLocation,
559 				last_ext->extLength, 1);
560 
561 		/*
562 		 * We've rewritten the last extent. If we are going to add
563 		 * more extents, we may need to enter possible following
564 		 * empty indirect extent.
565 		 */
566 		if (new_block_bytes) {
567 			err = udf_next_aext(inode, last_pos, &tmploc, &tmplen,
568 					    &tmptype, 0);
569 			if (err < 0)
570 				goto out_err;
571 		}
572 	}
573 	iinfo->i_lenExtents += add;
574 
575 	/* Managed to do everything necessary? */
576 	if (!new_block_bytes)
577 		goto out;
578 
579 	/* All further extents will be NOT_RECORDED_NOT_ALLOCATED */
580 	last_ext->extLocation.logicalBlockNum = 0;
581 	last_ext->extLocation.partitionReferenceNum = 0;
582 	add = (1 << 30) - sb->s_blocksize;
583 	last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED | add;
584 
585 	/* Create enough extents to cover the whole hole */
586 	while (new_block_bytes > add) {
587 		new_block_bytes -= add;
588 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
589 				   last_ext->extLength, 1);
590 		if (err)
591 			goto out_err;
592 		iinfo->i_lenExtents += add;
593 		count++;
594 	}
595 	if (new_block_bytes) {
596 		last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
597 			new_block_bytes;
598 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
599 				   last_ext->extLength, 1);
600 		if (err)
601 			goto out_err;
602 		iinfo->i_lenExtents += new_block_bytes;
603 		count++;
604 	}
605 
606 out:
607 	/* last_pos should point to the last written extent... */
608 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
609 		last_pos->offset -= sizeof(struct short_ad);
610 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
611 		last_pos->offset -= sizeof(struct long_ad);
612 	else
613 		return -EIO;
614 
615 	return count;
616 out_err:
617 	/* Remove extents we've created so far */
618 	udf_clear_extent_cache(inode);
619 	udf_truncate_extents(inode);
620 	return err;
621 }
622 
623 /* Extend the final block of the file to final_block_len bytes */
624 static void udf_do_extend_final_block(struct inode *inode,
625 				      struct extent_position *last_pos,
626 				      struct kernel_long_ad *last_ext,
627 				      uint32_t new_elen)
628 {
629 	uint32_t added_bytes;
630 
631 	/*
632 	 * Extent already large enough? It may be already rounded up to block
633 	 * size...
634 	 */
635 	if (new_elen <= (last_ext->extLength & UDF_EXTENT_LENGTH_MASK))
636 		return;
637 	added_bytes = new_elen - (last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
638 	last_ext->extLength += added_bytes;
639 	UDF_I(inode)->i_lenExtents += added_bytes;
640 
641 	udf_write_aext(inode, last_pos, &last_ext->extLocation,
642 			last_ext->extLength, 1);
643 }
644 
645 static int udf_extend_file(struct inode *inode, loff_t newsize)
646 {
647 
648 	struct extent_position epos;
649 	struct kernel_lb_addr eloc;
650 	uint32_t elen;
651 	int8_t etype;
652 	struct super_block *sb = inode->i_sb;
653 	sector_t first_block = newsize >> sb->s_blocksize_bits, offset;
654 	loff_t new_elen;
655 	int adsize;
656 	struct udf_inode_info *iinfo = UDF_I(inode);
657 	struct kernel_long_ad extent;
658 	int err = 0;
659 	bool within_last_ext;
660 
661 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
662 		adsize = sizeof(struct short_ad);
663 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
664 		adsize = sizeof(struct long_ad);
665 	else
666 		BUG();
667 
668 	down_write(&iinfo->i_data_sem);
669 	/*
670 	 * When creating hole in file, just don't bother with preserving
671 	 * preallocation. It likely won't be very useful anyway.
672 	 */
673 	udf_discard_prealloc(inode);
674 
675 	err = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset, &etype);
676 	if (err < 0)
677 		goto out;
678 	within_last_ext = (err == 1);
679 	/* We don't expect extents past EOF... */
680 	WARN_ON_ONCE(within_last_ext &&
681 		     elen > ((loff_t)offset + 1) << inode->i_blkbits);
682 
683 	if ((!epos.bh && epos.offset == udf_file_entry_alloc_offset(inode)) ||
684 	    (epos.bh && epos.offset == sizeof(struct allocExtDesc))) {
685 		/* File has no extents at all or has empty last
686 		 * indirect extent! Create a fake extent... */
687 		extent.extLocation.logicalBlockNum = 0;
688 		extent.extLocation.partitionReferenceNum = 0;
689 		extent.extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
690 	} else {
691 		epos.offset -= adsize;
692 		err = udf_next_aext(inode, &epos, &extent.extLocation,
693 				    &extent.extLength, &etype, 0);
694 		if (err <= 0)
695 			goto out;
696 		extent.extLength |= etype << 30;
697 	}
698 
699 	new_elen = ((loff_t)offset << inode->i_blkbits) |
700 					(newsize & (sb->s_blocksize - 1));
701 
702 	/* File has extent covering the new size (could happen when extending
703 	 * inside a block)?
704 	 */
705 	if (within_last_ext) {
706 		/* Extending file within the last file block */
707 		udf_do_extend_final_block(inode, &epos, &extent, new_elen);
708 	} else {
709 		err = udf_do_extend_file(inode, &epos, &extent, new_elen);
710 	}
711 
712 	if (err < 0)
713 		goto out;
714 	err = 0;
715 out:
716 	brelse(epos.bh);
717 	up_write(&iinfo->i_data_sem);
718 	return err;
719 }
720 
721 static int inode_getblk(struct inode *inode, struct udf_map_rq *map)
722 {
723 	struct kernel_long_ad laarr[EXTENT_MERGE_SIZE];
724 	struct extent_position prev_epos, cur_epos, next_epos;
725 	int count = 0, startnum = 0, endnum = 0;
726 	uint32_t elen = 0, tmpelen;
727 	struct kernel_lb_addr eloc, tmpeloc;
728 	int c = 1;
729 	loff_t lbcount = 0, b_off = 0;
730 	udf_pblk_t newblocknum;
731 	sector_t offset = 0;
732 	int8_t etype, tmpetype;
733 	struct udf_inode_info *iinfo = UDF_I(inode);
734 	udf_pblk_t goal = 0, pgoal = 0;
735 	int lastblock = 0;
736 	bool isBeyondEOF = false;
737 	int ret = 0;
738 
739 	prev_epos.offset = udf_file_entry_alloc_offset(inode);
740 	prev_epos.block = iinfo->i_location;
741 	prev_epos.bh = NULL;
742 	cur_epos = next_epos = prev_epos;
743 	b_off = (loff_t)map->lblk << inode->i_sb->s_blocksize_bits;
744 
745 	/* find the extent which contains the block we are looking for.
746 	   alternate between laarr[0] and laarr[1] for locations of the
747 	   current extent, and the previous extent */
748 	do {
749 		if (prev_epos.bh != cur_epos.bh) {
750 			brelse(prev_epos.bh);
751 			get_bh(cur_epos.bh);
752 			prev_epos.bh = cur_epos.bh;
753 		}
754 		if (cur_epos.bh != next_epos.bh) {
755 			brelse(cur_epos.bh);
756 			get_bh(next_epos.bh);
757 			cur_epos.bh = next_epos.bh;
758 		}
759 
760 		lbcount += elen;
761 
762 		prev_epos.block = cur_epos.block;
763 		cur_epos.block = next_epos.block;
764 
765 		prev_epos.offset = cur_epos.offset;
766 		cur_epos.offset = next_epos.offset;
767 
768 		ret = udf_next_aext(inode, &next_epos, &eloc, &elen, &etype, 1);
769 		if (ret < 0) {
770 			goto out_free;
771 		} else if (ret == 0) {
772 			isBeyondEOF = true;
773 			break;
774 		}
775 
776 		c = !c;
777 
778 		laarr[c].extLength = (etype << 30) | elen;
779 		laarr[c].extLocation = eloc;
780 
781 		if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
782 			pgoal = eloc.logicalBlockNum +
783 				((elen + inode->i_sb->s_blocksize - 1) >>
784 				 inode->i_sb->s_blocksize_bits);
785 
786 		count++;
787 	} while (lbcount + elen <= b_off);
788 
789 	b_off -= lbcount;
790 	offset = b_off >> inode->i_sb->s_blocksize_bits;
791 	/*
792 	 * Move prev_epos and cur_epos into indirect extent if we are at
793 	 * the pointer to it
794 	 */
795 	ret = udf_next_aext(inode, &prev_epos, &tmpeloc, &tmpelen, &tmpetype, 0);
796 	if (ret < 0)
797 		goto out_free;
798 	ret = udf_next_aext(inode, &cur_epos, &tmpeloc, &tmpelen, &tmpetype, 0);
799 	if (ret < 0)
800 		goto out_free;
801 
802 	/* if the extent is allocated and recorded, return the block
803 	   if the extent is not a multiple of the blocksize, round up */
804 
805 	if (!isBeyondEOF && etype == (EXT_RECORDED_ALLOCATED >> 30)) {
806 		if (elen & (inode->i_sb->s_blocksize - 1)) {
807 			elen = EXT_RECORDED_ALLOCATED |
808 				((elen + inode->i_sb->s_blocksize - 1) &
809 				 ~(inode->i_sb->s_blocksize - 1));
810 			iinfo->i_lenExtents =
811 				ALIGN(iinfo->i_lenExtents,
812 				      inode->i_sb->s_blocksize);
813 			udf_write_aext(inode, &cur_epos, &eloc, elen, 1);
814 		}
815 		map->oflags = UDF_BLK_MAPPED;
816 		map->pblk = udf_get_lb_pblock(inode->i_sb, &eloc, offset);
817 		ret = 0;
818 		goto out_free;
819 	}
820 
821 	/* Are we beyond EOF and preallocated extent? */
822 	if (isBeyondEOF) {
823 		loff_t hole_len;
824 
825 		if (count) {
826 			if (c)
827 				laarr[0] = laarr[1];
828 			startnum = 1;
829 		} else {
830 			/* Create a fake extent when there's not one */
831 			memset(&laarr[0].extLocation, 0x00,
832 				sizeof(struct kernel_lb_addr));
833 			laarr[0].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
834 			/* Will udf_do_extend_file() create real extent from
835 			   a fake one? */
836 			startnum = (offset > 0);
837 		}
838 		/* Create extents for the hole between EOF and offset */
839 		hole_len = (loff_t)offset << inode->i_blkbits;
840 		ret = udf_do_extend_file(inode, &prev_epos, laarr, hole_len);
841 		if (ret < 0)
842 			goto out_free;
843 		c = 0;
844 		offset = 0;
845 		count += ret;
846 		/*
847 		 * Is there any real extent? - otherwise we overwrite the fake
848 		 * one...
849 		 */
850 		if (count)
851 			c = !c;
852 		laarr[c].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
853 			inode->i_sb->s_blocksize;
854 		memset(&laarr[c].extLocation, 0x00,
855 			sizeof(struct kernel_lb_addr));
856 		count++;
857 		endnum = c + 1;
858 		lastblock = 1;
859 	} else {
860 		endnum = startnum = ((count > 2) ? 2 : count);
861 
862 		/* if the current extent is in position 0,
863 		   swap it with the previous */
864 		if (!c && count != 1) {
865 			laarr[2] = laarr[0];
866 			laarr[0] = laarr[1];
867 			laarr[1] = laarr[2];
868 			c = 1;
869 		}
870 
871 		/* if the current block is located in an extent,
872 		   read the next extent */
873 		ret = udf_next_aext(inode, &next_epos, &eloc, &elen, &etype, 0);
874 		if (ret > 0) {
875 			laarr[c + 1].extLength = (etype << 30) | elen;
876 			laarr[c + 1].extLocation = eloc;
877 			count++;
878 			startnum++;
879 			endnum++;
880 		} else if (ret == 0)
881 			lastblock = 1;
882 		else
883 			goto out_free;
884 	}
885 
886 	/* if the current extent is not recorded but allocated, get the
887 	 * block in the extent corresponding to the requested block */
888 	if ((laarr[c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30))
889 		newblocknum = laarr[c].extLocation.logicalBlockNum + offset;
890 	else { /* otherwise, allocate a new block */
891 		if (iinfo->i_next_alloc_block == map->lblk)
892 			goal = iinfo->i_next_alloc_goal;
893 		if (!goal)
894 			goal = pgoal;
895 		if (!goal)
896 			goal = iinfo->i_location.logicalBlockNum + 1;
897 
898 		newblocknum = udf_new_block(inode->i_sb, inode,
899 				iinfo->i_location.partitionReferenceNum,
900 				goal, &ret);
901 		if (!newblocknum)
902 			goto out_free;
903 		if (isBeyondEOF)
904 			iinfo->i_lenExtents += inode->i_sb->s_blocksize;
905 	}
906 
907 	/* if the extent the requsted block is located in contains multiple
908 	 * blocks, split the extent into at most three extents. blocks prior
909 	 * to requested block, requested block, and blocks after requested
910 	 * block */
911 	udf_split_extents(inode, &c, offset, newblocknum, laarr, &endnum);
912 
913 	if (!(map->iflags & UDF_MAP_NOPREALLOC))
914 		udf_prealloc_extents(inode, c, lastblock, laarr, &endnum);
915 
916 	/* merge any continuous blocks in laarr */
917 	udf_merge_extents(inode, laarr, &endnum);
918 
919 	/* write back the new extents, inserting new extents if the new number
920 	 * of extents is greater than the old number, and deleting extents if
921 	 * the new number of extents is less than the old number */
922 	ret = udf_update_extents(inode, laarr, startnum, endnum, &prev_epos);
923 	if (ret < 0)
924 		goto out_free;
925 
926 	map->pblk = udf_get_pblock(inode->i_sb, newblocknum,
927 				iinfo->i_location.partitionReferenceNum, 0);
928 	if (!map->pblk) {
929 		ret = -EFSCORRUPTED;
930 		goto out_free;
931 	}
932 	map->oflags = UDF_BLK_NEW | UDF_BLK_MAPPED;
933 	iinfo->i_next_alloc_block = map->lblk + 1;
934 	iinfo->i_next_alloc_goal = newblocknum + 1;
935 	inode_set_ctime_current(inode);
936 
937 	mark_inode_dirty(inode);
938 	ret = 0;
939 out_free:
940 	brelse(prev_epos.bh);
941 	brelse(cur_epos.bh);
942 	brelse(next_epos.bh);
943 	return ret;
944 }
945 
946 static void udf_split_extents(struct inode *inode, int *c, int offset,
947 			       udf_pblk_t newblocknum,
948 			       struct kernel_long_ad *laarr, int *endnum)
949 {
950 	unsigned long blocksize = inode->i_sb->s_blocksize;
951 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
952 
953 	if ((laarr[*c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30) ||
954 	    (laarr[*c].extLength >> 30) ==
955 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
956 		int curr = *c;
957 		int blen = ((laarr[curr].extLength & UDF_EXTENT_LENGTH_MASK) +
958 			    blocksize - 1) >> blocksize_bits;
959 		int8_t etype = (laarr[curr].extLength >> 30);
960 
961 		if (blen == 1)
962 			;
963 		else if (!offset || blen == offset + 1) {
964 			laarr[curr + 2] = laarr[curr + 1];
965 			laarr[curr + 1] = laarr[curr];
966 		} else {
967 			laarr[curr + 3] = laarr[curr + 1];
968 			laarr[curr + 2] = laarr[curr + 1] = laarr[curr];
969 		}
970 
971 		if (offset) {
972 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
973 				udf_free_blocks(inode->i_sb, inode,
974 						&laarr[curr].extLocation,
975 						0, offset);
976 				laarr[curr].extLength =
977 					EXT_NOT_RECORDED_NOT_ALLOCATED |
978 					(offset << blocksize_bits);
979 				laarr[curr].extLocation.logicalBlockNum = 0;
980 				laarr[curr].extLocation.
981 						partitionReferenceNum = 0;
982 			} else
983 				laarr[curr].extLength = (etype << 30) |
984 					(offset << blocksize_bits);
985 			curr++;
986 			(*c)++;
987 			(*endnum)++;
988 		}
989 
990 		laarr[curr].extLocation.logicalBlockNum = newblocknum;
991 		if (etype == (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
992 			laarr[curr].extLocation.partitionReferenceNum =
993 				UDF_I(inode)->i_location.partitionReferenceNum;
994 		laarr[curr].extLength = EXT_RECORDED_ALLOCATED |
995 			blocksize;
996 		curr++;
997 
998 		if (blen != offset + 1) {
999 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
1000 				laarr[curr].extLocation.logicalBlockNum +=
1001 								offset + 1;
1002 			laarr[curr].extLength = (etype << 30) |
1003 				((blen - (offset + 1)) << blocksize_bits);
1004 			curr++;
1005 			(*endnum)++;
1006 		}
1007 	}
1008 }
1009 
1010 static void udf_prealloc_extents(struct inode *inode, int c, int lastblock,
1011 				 struct kernel_long_ad *laarr,
1012 				 int *endnum)
1013 {
1014 	int start, length = 0, currlength = 0, i;
1015 
1016 	if (*endnum >= (c + 1)) {
1017 		if (!lastblock)
1018 			return;
1019 		else
1020 			start = c;
1021 	} else {
1022 		if ((laarr[c + 1].extLength >> 30) ==
1023 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
1024 			start = c + 1;
1025 			length = currlength =
1026 				(((laarr[c + 1].extLength &
1027 					UDF_EXTENT_LENGTH_MASK) +
1028 				inode->i_sb->s_blocksize - 1) >>
1029 				inode->i_sb->s_blocksize_bits);
1030 		} else
1031 			start = c;
1032 	}
1033 
1034 	for (i = start + 1; i <= *endnum; i++) {
1035 		if (i == *endnum) {
1036 			if (lastblock)
1037 				length += UDF_DEFAULT_PREALLOC_BLOCKS;
1038 		} else if ((laarr[i].extLength >> 30) ==
1039 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
1040 			length += (((laarr[i].extLength &
1041 						UDF_EXTENT_LENGTH_MASK) +
1042 				    inode->i_sb->s_blocksize - 1) >>
1043 				    inode->i_sb->s_blocksize_bits);
1044 		} else
1045 			break;
1046 	}
1047 
1048 	if (length) {
1049 		int next = laarr[start].extLocation.logicalBlockNum +
1050 			(((laarr[start].extLength & UDF_EXTENT_LENGTH_MASK) +
1051 			  inode->i_sb->s_blocksize - 1) >>
1052 			  inode->i_sb->s_blocksize_bits);
1053 		int numalloc = udf_prealloc_blocks(inode->i_sb, inode,
1054 				laarr[start].extLocation.partitionReferenceNum,
1055 				next, (UDF_DEFAULT_PREALLOC_BLOCKS > length ?
1056 				length : UDF_DEFAULT_PREALLOC_BLOCKS) -
1057 				currlength);
1058 		if (numalloc) 	{
1059 			if (start == (c + 1))
1060 				laarr[start].extLength +=
1061 					(numalloc <<
1062 					 inode->i_sb->s_blocksize_bits);
1063 			else {
1064 				memmove(&laarr[c + 2], &laarr[c + 1],
1065 					sizeof(struct long_ad) * (*endnum - (c + 1)));
1066 				(*endnum)++;
1067 				laarr[c + 1].extLocation.logicalBlockNum = next;
1068 				laarr[c + 1].extLocation.partitionReferenceNum =
1069 					laarr[c].extLocation.
1070 							partitionReferenceNum;
1071 				laarr[c + 1].extLength =
1072 					EXT_NOT_RECORDED_ALLOCATED |
1073 					(numalloc <<
1074 					 inode->i_sb->s_blocksize_bits);
1075 				start = c + 1;
1076 			}
1077 
1078 			for (i = start + 1; numalloc && i < *endnum; i++) {
1079 				int elen = ((laarr[i].extLength &
1080 						UDF_EXTENT_LENGTH_MASK) +
1081 					    inode->i_sb->s_blocksize - 1) >>
1082 					    inode->i_sb->s_blocksize_bits;
1083 
1084 				if (elen > numalloc) {
1085 					laarr[i].extLength -=
1086 						(numalloc <<
1087 						 inode->i_sb->s_blocksize_bits);
1088 					numalloc = 0;
1089 				} else {
1090 					numalloc -= elen;
1091 					if (*endnum > (i + 1))
1092 						memmove(&laarr[i],
1093 							&laarr[i + 1],
1094 							sizeof(struct long_ad) *
1095 							(*endnum - (i + 1)));
1096 					i--;
1097 					(*endnum)--;
1098 				}
1099 			}
1100 			UDF_I(inode)->i_lenExtents +=
1101 				numalloc << inode->i_sb->s_blocksize_bits;
1102 		}
1103 	}
1104 }
1105 
1106 static void udf_merge_extents(struct inode *inode, struct kernel_long_ad *laarr,
1107 			      int *endnum)
1108 {
1109 	int i;
1110 	unsigned long blocksize = inode->i_sb->s_blocksize;
1111 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1112 
1113 	for (i = 0; i < (*endnum - 1); i++) {
1114 		struct kernel_long_ad *li /*l[i]*/ = &laarr[i];
1115 		struct kernel_long_ad *lip1 /*l[i plus 1]*/ = &laarr[i + 1];
1116 
1117 		if (((li->extLength >> 30) == (lip1->extLength >> 30)) &&
1118 			(((li->extLength >> 30) ==
1119 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) ||
1120 			((lip1->extLocation.logicalBlockNum -
1121 			  li->extLocation.logicalBlockNum) ==
1122 			(((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1123 			blocksize - 1) >> blocksize_bits)))) {
1124 
1125 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1126 			     (lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1127 			     blocksize - 1) <= UDF_EXTENT_LENGTH_MASK) {
1128 				li->extLength = lip1->extLength +
1129 					(((li->extLength &
1130 						UDF_EXTENT_LENGTH_MASK) +
1131 					 blocksize - 1) & ~(blocksize - 1));
1132 				if (*endnum > (i + 2))
1133 					memmove(&laarr[i + 1], &laarr[i + 2],
1134 						sizeof(struct long_ad) *
1135 						(*endnum - (i + 2)));
1136 				i--;
1137 				(*endnum)--;
1138 			}
1139 		} else if (((li->extLength >> 30) ==
1140 				(EXT_NOT_RECORDED_ALLOCATED >> 30)) &&
1141 			   ((lip1->extLength >> 30) ==
1142 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))) {
1143 			udf_free_blocks(inode->i_sb, inode, &li->extLocation, 0,
1144 					((li->extLength &
1145 					  UDF_EXTENT_LENGTH_MASK) +
1146 					 blocksize - 1) >> blocksize_bits);
1147 			li->extLocation.logicalBlockNum = 0;
1148 			li->extLocation.partitionReferenceNum = 0;
1149 
1150 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1151 			     (lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1152 			     blocksize - 1) & ~UDF_EXTENT_LENGTH_MASK) {
1153 				lip1->extLength = (lip1->extLength -
1154 						   (li->extLength &
1155 						   UDF_EXTENT_LENGTH_MASK) +
1156 						   UDF_EXTENT_LENGTH_MASK) &
1157 						   ~(blocksize - 1);
1158 				li->extLength = (li->extLength &
1159 						 UDF_EXTENT_FLAG_MASK) +
1160 						(UDF_EXTENT_LENGTH_MASK + 1) -
1161 						blocksize;
1162 			} else {
1163 				li->extLength = lip1->extLength +
1164 					(((li->extLength &
1165 						UDF_EXTENT_LENGTH_MASK) +
1166 					  blocksize - 1) & ~(blocksize - 1));
1167 				if (*endnum > (i + 2))
1168 					memmove(&laarr[i + 1], &laarr[i + 2],
1169 						sizeof(struct long_ad) *
1170 						(*endnum - (i + 2)));
1171 				i--;
1172 				(*endnum)--;
1173 			}
1174 		} else if ((li->extLength >> 30) ==
1175 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
1176 			udf_free_blocks(inode->i_sb, inode,
1177 					&li->extLocation, 0,
1178 					((li->extLength &
1179 						UDF_EXTENT_LENGTH_MASK) +
1180 					 blocksize - 1) >> blocksize_bits);
1181 			li->extLocation.logicalBlockNum = 0;
1182 			li->extLocation.partitionReferenceNum = 0;
1183 			li->extLength = (li->extLength &
1184 						UDF_EXTENT_LENGTH_MASK) |
1185 						EXT_NOT_RECORDED_NOT_ALLOCATED;
1186 		}
1187 	}
1188 }
1189 
1190 static int udf_update_extents(struct inode *inode, struct kernel_long_ad *laarr,
1191 			      int startnum, int endnum,
1192 			      struct extent_position *epos)
1193 {
1194 	int start = 0, i;
1195 	struct kernel_lb_addr tmploc;
1196 	uint32_t tmplen;
1197 	int8_t tmpetype;
1198 	int err;
1199 
1200 	if (startnum > endnum) {
1201 		for (i = 0; i < (startnum - endnum); i++)
1202 			udf_delete_aext(inode, *epos);
1203 	} else if (startnum < endnum) {
1204 		for (i = 0; i < (endnum - startnum); i++) {
1205 			err = udf_insert_aext(inode, *epos,
1206 					      laarr[i].extLocation,
1207 					      laarr[i].extLength);
1208 			/*
1209 			 * If we fail here, we are likely corrupting the extent
1210 			 * list and leaking blocks. At least stop early to
1211 			 * limit the damage.
1212 			 */
1213 			if (err < 0)
1214 				return err;
1215 			err = udf_next_aext(inode, epos, &laarr[i].extLocation,
1216 				      &laarr[i].extLength, &tmpetype, 1);
1217 			if (err < 0)
1218 				return err;
1219 			start++;
1220 		}
1221 	}
1222 
1223 	for (i = start; i < endnum; i++) {
1224 		err = udf_next_aext(inode, epos, &tmploc, &tmplen, &tmpetype, 0);
1225 		if (err < 0)
1226 			return err;
1227 
1228 		udf_write_aext(inode, epos, &laarr[i].extLocation,
1229 			       laarr[i].extLength, 1);
1230 	}
1231 	return 0;
1232 }
1233 
1234 struct buffer_head *udf_bread(struct inode *inode, udf_pblk_t block,
1235 			      int create, int *err)
1236 {
1237 	struct buffer_head *bh = NULL;
1238 	struct udf_map_rq map = {
1239 		.lblk = block,
1240 		.iflags = UDF_MAP_NOPREALLOC | (create ? UDF_MAP_CREATE : 0),
1241 	};
1242 
1243 	*err = udf_map_block(inode, &map);
1244 	if (*err || !(map.oflags & UDF_BLK_MAPPED))
1245 		return NULL;
1246 
1247 	bh = sb_getblk(inode->i_sb, map.pblk);
1248 	if (!bh) {
1249 		*err = -ENOMEM;
1250 		return NULL;
1251 	}
1252 	if (map.oflags & UDF_BLK_NEW) {
1253 		lock_buffer(bh);
1254 		memset(bh->b_data, 0x00, inode->i_sb->s_blocksize);
1255 		set_buffer_uptodate(bh);
1256 		unlock_buffer(bh);
1257 		mmb_mark_buffer_dirty(bh, &UDF_I(inode)->i_metadata_bhs);
1258 		return bh;
1259 	}
1260 
1261 	if (bh_read(bh, 0) >= 0)
1262 		return bh;
1263 
1264 	brelse(bh);
1265 	*err = -EIO;
1266 	return NULL;
1267 }
1268 
1269 int udf_setsize(struct inode *inode, loff_t newsize)
1270 {
1271 	int err = 0;
1272 	struct udf_inode_info *iinfo;
1273 	unsigned int bsize = i_blocksize(inode);
1274 
1275 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1276 	      S_ISLNK(inode->i_mode)))
1277 		return -EINVAL;
1278 
1279 	iinfo = UDF_I(inode);
1280 	if (newsize > inode->i_size) {
1281 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1282 			if (bsize >=
1283 			    (udf_file_entry_alloc_offset(inode) + newsize)) {
1284 				down_write(&iinfo->i_data_sem);
1285 				iinfo->i_lenAlloc = newsize;
1286 				up_write(&iinfo->i_data_sem);
1287 				goto set_size;
1288 			}
1289 			err = udf_expand_file_adinicb(inode);
1290 			if (err)
1291 				return err;
1292 		}
1293 		err = udf_extend_file(inode, newsize);
1294 		if (err)
1295 			return err;
1296 set_size:
1297 		truncate_setsize(inode, newsize);
1298 	} else {
1299 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1300 			down_write(&iinfo->i_data_sem);
1301 			udf_clear_extent_cache(inode);
1302 			memset(iinfo->i_data + iinfo->i_lenEAttr + newsize,
1303 			       0x00, bsize - newsize -
1304 			       udf_file_entry_alloc_offset(inode));
1305 			iinfo->i_lenAlloc = newsize;
1306 			truncate_setsize(inode, newsize);
1307 			up_write(&iinfo->i_data_sem);
1308 			goto update_time;
1309 		}
1310 		err = block_truncate_page(inode->i_mapping, newsize,
1311 					  udf_get_block);
1312 		if (err)
1313 			return err;
1314 		truncate_setsize(inode, newsize);
1315 		down_write(&iinfo->i_data_sem);
1316 		udf_clear_extent_cache(inode);
1317 		err = udf_truncate_extents(inode);
1318 		up_write(&iinfo->i_data_sem);
1319 		if (err)
1320 			return err;
1321 	}
1322 update_time:
1323 	inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
1324 	mark_inode_dirty(inode);
1325 	return err;
1326 }
1327 
1328 /*
1329  * Maximum length of linked list formed by ICB hierarchy. The chosen number is
1330  * arbitrary - just that we hopefully don't limit any real use of rewritten
1331  * inode on write-once media but avoid looping for too long on corrupted media.
1332  */
1333 #define UDF_MAX_ICB_NESTING 1024
1334 
1335 static int udf_read_inode(struct inode *inode, bool hidden_inode)
1336 {
1337 	struct buffer_head *bh = NULL;
1338 	struct fileEntry *fe;
1339 	struct extendedFileEntry *efe;
1340 	uint16_t ident;
1341 	struct udf_inode_info *iinfo = UDF_I(inode);
1342 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1343 	struct kernel_lb_addr *iloc = &iinfo->i_location;
1344 	unsigned int link_count;
1345 	unsigned int indirections = 0;
1346 	int bs = inode->i_sb->s_blocksize;
1347 	int ret = -EIO;
1348 	uint32_t uid, gid;
1349 	struct timespec64 ts;
1350 
1351 reread:
1352 	if (iloc->partitionReferenceNum >= sbi->s_partitions) {
1353 		udf_debug("partition reference: %u > logical volume partitions: %u\n",
1354 			  iloc->partitionReferenceNum, sbi->s_partitions);
1355 		return -EIO;
1356 	}
1357 
1358 	if (iloc->logicalBlockNum >=
1359 	    sbi->s_partmaps[iloc->partitionReferenceNum].s_partition_len) {
1360 		udf_debug("block=%u, partition=%u out of range\n",
1361 			  iloc->logicalBlockNum, iloc->partitionReferenceNum);
1362 		return -EIO;
1363 	}
1364 
1365 	/*
1366 	 * Set defaults, but the inode is still incomplete!
1367 	 * Note: get_new_inode() sets the following on a new inode:
1368 	 *      i_sb = sb
1369 	 *      i_no = ino
1370 	 *      i_flags = sb->s_flags
1371 	 *      i_state = 0
1372 	 * clean_inode(): zero fills and sets
1373 	 *      i_count = 1
1374 	 *      i_nlink = 1
1375 	 *      i_op = NULL;
1376 	 */
1377 	bh = udf_read_ptagged(inode->i_sb, iloc, 0, &ident);
1378 	if (!bh) {
1379 		udf_err(inode->i_sb, "(ino %llu) failed !bh\n", inode->i_ino);
1380 		return -EIO;
1381 	}
1382 
1383 	if (ident != TAG_IDENT_FE && ident != TAG_IDENT_EFE &&
1384 	    ident != TAG_IDENT_USE) {
1385 		udf_err(inode->i_sb, "(ino %llu) failed ident=%u\n",
1386 			inode->i_ino, ident);
1387 		goto out;
1388 	}
1389 
1390 	fe = (struct fileEntry *)bh->b_data;
1391 	efe = (struct extendedFileEntry *)bh->b_data;
1392 
1393 	if (fe->icbTag.strategyType == cpu_to_le16(4096)) {
1394 		struct buffer_head *ibh;
1395 
1396 		ibh = udf_read_ptagged(inode->i_sb, iloc, 1, &ident);
1397 		if (ident == TAG_IDENT_IE && ibh) {
1398 			struct kernel_lb_addr loc;
1399 			struct indirectEntry *ie;
1400 
1401 			ie = (struct indirectEntry *)ibh->b_data;
1402 			loc = lelb_to_cpu(ie->indirectICB.extLocation);
1403 
1404 			if (ie->indirectICB.extLength) {
1405 				brelse(ibh);
1406 				memcpy(&iinfo->i_location, &loc,
1407 				       sizeof(struct kernel_lb_addr));
1408 				if (++indirections > UDF_MAX_ICB_NESTING) {
1409 					udf_err(inode->i_sb,
1410 						"too many ICBs in ICB hierarchy"
1411 						" (max %d supported)\n",
1412 						UDF_MAX_ICB_NESTING);
1413 					goto out;
1414 				}
1415 				brelse(bh);
1416 				goto reread;
1417 			}
1418 		}
1419 		brelse(ibh);
1420 	} else if (fe->icbTag.strategyType != cpu_to_le16(4)) {
1421 		udf_err(inode->i_sb, "unsupported strategy type: %u\n",
1422 			le16_to_cpu(fe->icbTag.strategyType));
1423 		goto out;
1424 	}
1425 	if (fe->icbTag.strategyType == cpu_to_le16(4))
1426 		iinfo->i_strat4096 = 0;
1427 	else /* if (fe->icbTag.strategyType == cpu_to_le16(4096)) */
1428 		iinfo->i_strat4096 = 1;
1429 
1430 	iinfo->i_alloc_type = le16_to_cpu(fe->icbTag.flags) &
1431 							ICBTAG_FLAG_AD_MASK;
1432 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_SHORT &&
1433 	    iinfo->i_alloc_type != ICBTAG_FLAG_AD_LONG &&
1434 	    iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
1435 		ret = -EIO;
1436 		goto out;
1437 	}
1438 	iinfo->i_hidden = hidden_inode;
1439 	iinfo->i_unique = 0;
1440 	iinfo->i_lenEAttr = 0;
1441 	iinfo->i_lenExtents = 0;
1442 	iinfo->i_lenAlloc = 0;
1443 	iinfo->i_next_alloc_block = 0;
1444 	iinfo->i_next_alloc_goal = 0;
1445 	if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_EFE)) {
1446 		iinfo->i_efe = 1;
1447 		iinfo->i_use = 0;
1448 		ret = udf_alloc_i_data(inode, bs -
1449 					sizeof(struct extendedFileEntry));
1450 		if (ret)
1451 			goto out;
1452 		memcpy(iinfo->i_data,
1453 		       bh->b_data + sizeof(struct extendedFileEntry),
1454 		       bs - sizeof(struct extendedFileEntry));
1455 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_FE)) {
1456 		iinfo->i_efe = 0;
1457 		iinfo->i_use = 0;
1458 		ret = udf_alloc_i_data(inode, bs - sizeof(struct fileEntry));
1459 		if (ret)
1460 			goto out;
1461 		memcpy(iinfo->i_data,
1462 		       bh->b_data + sizeof(struct fileEntry),
1463 		       bs - sizeof(struct fileEntry));
1464 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_USE)) {
1465 		iinfo->i_efe = 0;
1466 		iinfo->i_use = 1;
1467 		iinfo->i_lenAlloc = le32_to_cpu(
1468 				((struct unallocSpaceEntry *)bh->b_data)->
1469 				 lengthAllocDescs);
1470 		ret = udf_alloc_i_data(inode, bs -
1471 					sizeof(struct unallocSpaceEntry));
1472 		if (ret)
1473 			goto out;
1474 		memcpy(iinfo->i_data,
1475 		       bh->b_data + sizeof(struct unallocSpaceEntry),
1476 		       bs - sizeof(struct unallocSpaceEntry));
1477 		return 0;
1478 	}
1479 
1480 	ret = -EIO;
1481 	read_lock(&sbi->s_cred_lock);
1482 	uid = le32_to_cpu(fe->uid);
1483 	if (uid == UDF_INVALID_ID ||
1484 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_SET))
1485 		inode->i_uid = sbi->s_uid;
1486 	else
1487 		i_uid_write(inode, uid);
1488 
1489 	gid = le32_to_cpu(fe->gid);
1490 	if (gid == UDF_INVALID_ID ||
1491 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_SET))
1492 		inode->i_gid = sbi->s_gid;
1493 	else
1494 		i_gid_write(inode, gid);
1495 
1496 	if (fe->icbTag.fileType != ICBTAG_FILE_TYPE_DIRECTORY &&
1497 			sbi->s_fmode != UDF_INVALID_MODE)
1498 		inode->i_mode = sbi->s_fmode;
1499 	else if (fe->icbTag.fileType == ICBTAG_FILE_TYPE_DIRECTORY &&
1500 			sbi->s_dmode != UDF_INVALID_MODE)
1501 		inode->i_mode = sbi->s_dmode;
1502 	else
1503 		inode->i_mode = udf_convert_permissions(fe);
1504 	inode->i_mode &= ~sbi->s_umask;
1505 	iinfo->i_extraPerms = le32_to_cpu(fe->permissions) & ~FE_MAPPED_PERMS;
1506 
1507 	read_unlock(&sbi->s_cred_lock);
1508 
1509 	link_count = le16_to_cpu(fe->fileLinkCount);
1510 	if (!link_count) {
1511 		if (!hidden_inode) {
1512 			ret = -ESTALE;
1513 			goto out;
1514 		}
1515 		link_count = 1;
1516 	}
1517 	set_nlink(inode, link_count);
1518 
1519 	inode->i_size = le64_to_cpu(fe->informationLength);
1520 	iinfo->i_lenExtents = inode->i_size;
1521 
1522 	if (iinfo->i_efe == 0) {
1523 		inode->i_blocks = le64_to_cpu(fe->logicalBlocksRecorded) <<
1524 			(inode->i_sb->s_blocksize_bits - 9);
1525 
1526 		udf_disk_stamp_to_time(&ts, fe->accessTime);
1527 		inode_set_atime_to_ts(inode, ts);
1528 		udf_disk_stamp_to_time(&ts, fe->modificationTime);
1529 		inode_set_mtime_to_ts(inode, ts);
1530 		udf_disk_stamp_to_time(&ts, fe->attrTime);
1531 		inode_set_ctime_to_ts(inode, ts);
1532 
1533 		iinfo->i_unique = le64_to_cpu(fe->uniqueID);
1534 		iinfo->i_lenEAttr = le32_to_cpu(fe->lengthExtendedAttr);
1535 		iinfo->i_lenAlloc = le32_to_cpu(fe->lengthAllocDescs);
1536 		iinfo->i_checkpoint = le32_to_cpu(fe->checkpoint);
1537 		iinfo->i_streamdir = 0;
1538 		iinfo->i_lenStreams = 0;
1539 	} else {
1540 		inode->i_blocks = le64_to_cpu(efe->logicalBlocksRecorded) <<
1541 		    (inode->i_sb->s_blocksize_bits - 9);
1542 
1543 		udf_disk_stamp_to_time(&ts, efe->accessTime);
1544 		inode_set_atime_to_ts(inode, ts);
1545 		udf_disk_stamp_to_time(&ts, efe->modificationTime);
1546 		inode_set_mtime_to_ts(inode, ts);
1547 		udf_disk_stamp_to_time(&ts, efe->attrTime);
1548 		inode_set_ctime_to_ts(inode, ts);
1549 		udf_disk_stamp_to_time(&iinfo->i_crtime, efe->createTime);
1550 
1551 		iinfo->i_unique = le64_to_cpu(efe->uniqueID);
1552 		iinfo->i_lenEAttr = le32_to_cpu(efe->lengthExtendedAttr);
1553 		iinfo->i_lenAlloc = le32_to_cpu(efe->lengthAllocDescs);
1554 		iinfo->i_checkpoint = le32_to_cpu(efe->checkpoint);
1555 
1556 		/* Named streams */
1557 		iinfo->i_streamdir = (efe->streamDirectoryICB.extLength != 0);
1558 		iinfo->i_locStreamdir =
1559 			lelb_to_cpu(efe->streamDirectoryICB.extLocation);
1560 		iinfo->i_lenStreams = le64_to_cpu(efe->objectSize);
1561 		if (iinfo->i_lenStreams >= inode->i_size)
1562 			iinfo->i_lenStreams -= inode->i_size;
1563 		else
1564 			iinfo->i_lenStreams = 0;
1565 	}
1566 	inode->i_generation = iinfo->i_unique;
1567 
1568 	/*
1569 	 * Sanity check length of allocation descriptors and extended attrs to
1570 	 * avoid integer overflows
1571 	 */
1572 	if (iinfo->i_lenEAttr > bs || iinfo->i_lenAlloc > bs)
1573 		goto out;
1574 	/* Now do exact checks */
1575 	if (udf_file_entry_alloc_offset(inode) + iinfo->i_lenAlloc > bs)
1576 		goto out;
1577 	/* Sanity checks for files in ICB so that we don't get confused later */
1578 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1579 		/*
1580 		 * For file in ICB data is stored in allocation descriptor
1581 		 * so sizes should match
1582 		 */
1583 		if (iinfo->i_lenAlloc != inode->i_size)
1584 			goto out;
1585 		/* File in ICB has to fit in there... */
1586 		if (inode->i_size > bs - udf_file_entry_alloc_offset(inode))
1587 			goto out;
1588 	}
1589 
1590 	switch (fe->icbTag.fileType) {
1591 	case ICBTAG_FILE_TYPE_DIRECTORY:
1592 		inode->i_op = &udf_dir_inode_operations;
1593 		inode->i_fop = &udf_dir_operations;
1594 		inode->i_mode |= S_IFDIR;
1595 		inc_nlink(inode);
1596 		break;
1597 	case ICBTAG_FILE_TYPE_REALTIME:
1598 	case ICBTAG_FILE_TYPE_REGULAR:
1599 	case ICBTAG_FILE_TYPE_UNDEF:
1600 	case ICBTAG_FILE_TYPE_VAT20:
1601 		inode->i_data.a_ops = &udf_aops;
1602 		inode->i_op = &udf_file_inode_operations;
1603 		inode->i_fop = &udf_file_operations;
1604 		inode->i_mode |= S_IFREG;
1605 		break;
1606 	case ICBTAG_FILE_TYPE_BLOCK:
1607 		inode->i_mode |= S_IFBLK;
1608 		break;
1609 	case ICBTAG_FILE_TYPE_CHAR:
1610 		inode->i_mode |= S_IFCHR;
1611 		break;
1612 	case ICBTAG_FILE_TYPE_FIFO:
1613 		init_special_inode(inode, inode->i_mode | S_IFIFO, 0);
1614 		break;
1615 	case ICBTAG_FILE_TYPE_SOCKET:
1616 		init_special_inode(inode, inode->i_mode | S_IFSOCK, 0);
1617 		break;
1618 	case ICBTAG_FILE_TYPE_SYMLINK:
1619 		inode->i_data.a_ops = &udf_symlink_aops;
1620 		inode->i_op = &udf_symlink_inode_operations;
1621 		inode_nohighmem(inode);
1622 		inode->i_mode = S_IFLNK | 0777;
1623 		break;
1624 	case ICBTAG_FILE_TYPE_MAIN:
1625 		udf_debug("METADATA FILE-----\n");
1626 		break;
1627 	case ICBTAG_FILE_TYPE_MIRROR:
1628 		udf_debug("METADATA MIRROR FILE-----\n");
1629 		break;
1630 	case ICBTAG_FILE_TYPE_BITMAP:
1631 		udf_debug("METADATA BITMAP FILE-----\n");
1632 		break;
1633 	default:
1634 		udf_err(inode->i_sb, "(ino %llu) failed unknown file type=%u\n",
1635 			inode->i_ino, fe->icbTag.fileType);
1636 		goto out;
1637 	}
1638 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1639 		struct deviceSpec *dsea =
1640 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1641 		if (dsea) {
1642 			init_special_inode(inode, inode->i_mode,
1643 				MKDEV(le32_to_cpu(dsea->majorDeviceIdent),
1644 				      le32_to_cpu(dsea->minorDeviceIdent)));
1645 			/* Developer ID ??? */
1646 		} else
1647 			goto out;
1648 	}
1649 	ret = 0;
1650 out:
1651 	brelse(bh);
1652 	return ret;
1653 }
1654 
1655 static int udf_alloc_i_data(struct inode *inode, size_t size)
1656 {
1657 	struct udf_inode_info *iinfo = UDF_I(inode);
1658 	iinfo->i_data = kmalloc(size, GFP_KERNEL);
1659 	if (!iinfo->i_data)
1660 		return -ENOMEM;
1661 	return 0;
1662 }
1663 
1664 static umode_t udf_convert_permissions(struct fileEntry *fe)
1665 {
1666 	umode_t mode;
1667 	uint32_t permissions;
1668 	uint32_t flags;
1669 
1670 	permissions = le32_to_cpu(fe->permissions);
1671 	flags = le16_to_cpu(fe->icbTag.flags);
1672 
1673 	mode =	((permissions) & 0007) |
1674 		((permissions >> 2) & 0070) |
1675 		((permissions >> 4) & 0700) |
1676 		((flags & ICBTAG_FLAG_SETUID) ? S_ISUID : 0) |
1677 		((flags & ICBTAG_FLAG_SETGID) ? S_ISGID : 0) |
1678 		((flags & ICBTAG_FLAG_STICKY) ? S_ISVTX : 0);
1679 
1680 	return mode;
1681 }
1682 
1683 void udf_update_extra_perms(struct inode *inode, umode_t mode)
1684 {
1685 	struct udf_inode_info *iinfo = UDF_I(inode);
1686 
1687 	/*
1688 	 * UDF 2.01 sec. 3.3.3.3 Note 2:
1689 	 * In Unix, delete permission tracks write
1690 	 */
1691 	iinfo->i_extraPerms &= ~FE_DELETE_PERMS;
1692 	if (mode & 0200)
1693 		iinfo->i_extraPerms |= FE_PERM_U_DELETE;
1694 	if (mode & 0020)
1695 		iinfo->i_extraPerms |= FE_PERM_G_DELETE;
1696 	if (mode & 0002)
1697 		iinfo->i_extraPerms |= FE_PERM_O_DELETE;
1698 }
1699 
1700 int udf_sync_inode_metadata(struct inode *inode, struct writeback_control *wbc)
1701 {
1702 	struct buffer_head *bh;
1703 	int err = 0;
1704 
1705 	bh = sb_getblk(inode->i_sb,
1706 			udf_get_lb_pblock(inode->i_sb,
1707 					  &UDF_I(inode)->i_location, 0));
1708 	if (!bh)
1709 		return -EIO;
1710 
1711 	sync_dirty_buffer(bh);
1712 	if (buffer_write_io_error(bh)) {
1713 		udf_warn(inode->i_sb, "IO error syncing udf inode [%08llx]\n",
1714 			 inode->i_ino);
1715 		err = -EIO;
1716 		goto out;
1717 	}
1718 	err = mmb_sync(&UDF_I(inode)->i_metadata_bhs);
1719 out:
1720 	brelse(bh);
1721 	return err;
1722 }
1723 
1724 static void udf_adjust_time(struct udf_inode_info *iinfo, struct timespec64 time)
1725 {
1726 	if (iinfo->i_crtime.tv_sec > time.tv_sec ||
1727 	    (iinfo->i_crtime.tv_sec == time.tv_sec &&
1728 	     iinfo->i_crtime.tv_nsec > time.tv_nsec))
1729 		iinfo->i_crtime = time;
1730 }
1731 
1732 int udf_write_inode(struct inode *inode, struct writeback_control *wbc)
1733 {
1734 	struct buffer_head *bh = NULL;
1735 	struct fileEntry *fe;
1736 	struct extendedFileEntry *efe;
1737 	uint64_t lb_recorded;
1738 	uint32_t udfperms;
1739 	uint16_t icbflags;
1740 	uint16_t crclen;
1741 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1742 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1743 	struct udf_inode_info *iinfo = UDF_I(inode);
1744 
1745 	bh = sb_getblk(inode->i_sb,
1746 			udf_get_lb_pblock(inode->i_sb, &iinfo->i_location, 0));
1747 	if (!bh) {
1748 		udf_debug("getblk failure\n");
1749 		return -EIO;
1750 	}
1751 
1752 	lock_buffer(bh);
1753 	memset(bh->b_data, 0, inode->i_sb->s_blocksize);
1754 	fe = (struct fileEntry *)bh->b_data;
1755 	efe = (struct extendedFileEntry *)bh->b_data;
1756 
1757 	if (iinfo->i_use) {
1758 		struct unallocSpaceEntry *use =
1759 			(struct unallocSpaceEntry *)bh->b_data;
1760 
1761 		use->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1762 		memcpy(bh->b_data + sizeof(struct unallocSpaceEntry),
1763 		       iinfo->i_data, inode->i_sb->s_blocksize -
1764 					sizeof(struct unallocSpaceEntry));
1765 		use->descTag.tagIdent = cpu_to_le16(TAG_IDENT_USE);
1766 		crclen = sizeof(struct unallocSpaceEntry);
1767 
1768 		goto finish;
1769 	}
1770 
1771 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_FORGET))
1772 		fe->uid = cpu_to_le32(UDF_INVALID_ID);
1773 	else
1774 		fe->uid = cpu_to_le32(i_uid_read(inode));
1775 
1776 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_FORGET))
1777 		fe->gid = cpu_to_le32(UDF_INVALID_ID);
1778 	else
1779 		fe->gid = cpu_to_le32(i_gid_read(inode));
1780 
1781 	udfperms = ((inode->i_mode & 0007)) |
1782 		   ((inode->i_mode & 0070) << 2) |
1783 		   ((inode->i_mode & 0700) << 4);
1784 
1785 	udfperms |= iinfo->i_extraPerms;
1786 	fe->permissions = cpu_to_le32(udfperms);
1787 
1788 	if (S_ISDIR(inode->i_mode) && inode->i_nlink > 0)
1789 		fe->fileLinkCount = cpu_to_le16(inode->i_nlink - 1);
1790 	else {
1791 		if (iinfo->i_hidden)
1792 			fe->fileLinkCount = cpu_to_le16(0);
1793 		else
1794 			fe->fileLinkCount = cpu_to_le16(inode->i_nlink);
1795 	}
1796 
1797 	fe->informationLength = cpu_to_le64(inode->i_size);
1798 
1799 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1800 		struct regid *eid;
1801 		struct deviceSpec *dsea =
1802 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1803 		if (!dsea) {
1804 			dsea = (struct deviceSpec *)
1805 				udf_add_extendedattr(inode,
1806 						     sizeof(struct deviceSpec) +
1807 						     sizeof(struct regid), 12, 0x3);
1808 			dsea->attrType = cpu_to_le32(12);
1809 			dsea->attrSubtype = 1;
1810 			dsea->attrLength = cpu_to_le32(
1811 						sizeof(struct deviceSpec) +
1812 						sizeof(struct regid));
1813 			dsea->impUseLength = cpu_to_le32(sizeof(struct regid));
1814 		}
1815 		eid = (struct regid *)dsea->impUse;
1816 		memset(eid, 0, sizeof(*eid));
1817 		strcpy(eid->ident, UDF_ID_DEVELOPER);
1818 		eid->identSuffix[0] = UDF_OS_CLASS_UNIX;
1819 		eid->identSuffix[1] = UDF_OS_ID_LINUX;
1820 		dsea->majorDeviceIdent = cpu_to_le32(imajor(inode));
1821 		dsea->minorDeviceIdent = cpu_to_le32(iminor(inode));
1822 	}
1823 
1824 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1825 		lb_recorded = 0; /* No extents => no blocks! */
1826 	else
1827 		lb_recorded =
1828 			(inode->i_blocks + (1 << (blocksize_bits - 9)) - 1) >>
1829 			(blocksize_bits - 9);
1830 
1831 	if (iinfo->i_efe == 0) {
1832 		memcpy(bh->b_data + sizeof(struct fileEntry),
1833 		       iinfo->i_data,
1834 		       inode->i_sb->s_blocksize - sizeof(struct fileEntry));
1835 		fe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
1836 
1837 		udf_time_to_disk_stamp(&fe->accessTime, inode_get_atime(inode));
1838 		udf_time_to_disk_stamp(&fe->modificationTime, inode_get_mtime(inode));
1839 		udf_time_to_disk_stamp(&fe->attrTime, inode_get_ctime(inode));
1840 		memset(&(fe->impIdent), 0, sizeof(struct regid));
1841 		strcpy(fe->impIdent.ident, UDF_ID_DEVELOPER);
1842 		fe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1843 		fe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1844 		fe->uniqueID = cpu_to_le64(iinfo->i_unique);
1845 		fe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
1846 		fe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1847 		fe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
1848 		fe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_FE);
1849 		crclen = sizeof(struct fileEntry);
1850 	} else {
1851 		memcpy(bh->b_data + sizeof(struct extendedFileEntry),
1852 		       iinfo->i_data,
1853 		       inode->i_sb->s_blocksize -
1854 					sizeof(struct extendedFileEntry));
1855 		efe->objectSize =
1856 			cpu_to_le64(inode->i_size + iinfo->i_lenStreams);
1857 		efe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
1858 
1859 		if (iinfo->i_streamdir) {
1860 			struct long_ad *icb_lad = &efe->streamDirectoryICB;
1861 
1862 			icb_lad->extLocation =
1863 				cpu_to_lelb(iinfo->i_locStreamdir);
1864 			icb_lad->extLength =
1865 				cpu_to_le32(inode->i_sb->s_blocksize);
1866 		}
1867 
1868 		udf_adjust_time(iinfo, inode_get_atime(inode));
1869 		udf_adjust_time(iinfo, inode_get_mtime(inode));
1870 		udf_adjust_time(iinfo, inode_get_ctime(inode));
1871 
1872 		udf_time_to_disk_stamp(&efe->accessTime,
1873 				       inode_get_atime(inode));
1874 		udf_time_to_disk_stamp(&efe->modificationTime,
1875 				       inode_get_mtime(inode));
1876 		udf_time_to_disk_stamp(&efe->createTime, iinfo->i_crtime);
1877 		udf_time_to_disk_stamp(&efe->attrTime, inode_get_ctime(inode));
1878 
1879 		memset(&(efe->impIdent), 0, sizeof(efe->impIdent));
1880 		strcpy(efe->impIdent.ident, UDF_ID_DEVELOPER);
1881 		efe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1882 		efe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1883 		efe->uniqueID = cpu_to_le64(iinfo->i_unique);
1884 		efe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
1885 		efe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1886 		efe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
1887 		efe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EFE);
1888 		crclen = sizeof(struct extendedFileEntry);
1889 	}
1890 
1891 finish:
1892 	if (iinfo->i_strat4096) {
1893 		fe->icbTag.strategyType = cpu_to_le16(4096);
1894 		fe->icbTag.strategyParameter = cpu_to_le16(1);
1895 		fe->icbTag.numEntries = cpu_to_le16(2);
1896 	} else {
1897 		fe->icbTag.strategyType = cpu_to_le16(4);
1898 		fe->icbTag.numEntries = cpu_to_le16(1);
1899 	}
1900 
1901 	if (iinfo->i_use)
1902 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_USE;
1903 	else if (S_ISDIR(inode->i_mode))
1904 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_DIRECTORY;
1905 	else if (S_ISREG(inode->i_mode))
1906 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_REGULAR;
1907 	else if (S_ISLNK(inode->i_mode))
1908 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SYMLINK;
1909 	else if (S_ISBLK(inode->i_mode))
1910 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_BLOCK;
1911 	else if (S_ISCHR(inode->i_mode))
1912 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_CHAR;
1913 	else if (S_ISFIFO(inode->i_mode))
1914 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_FIFO;
1915 	else if (S_ISSOCK(inode->i_mode))
1916 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SOCKET;
1917 
1918 	icbflags =	iinfo->i_alloc_type |
1919 			((inode->i_mode & S_ISUID) ? ICBTAG_FLAG_SETUID : 0) |
1920 			((inode->i_mode & S_ISGID) ? ICBTAG_FLAG_SETGID : 0) |
1921 			((inode->i_mode & S_ISVTX) ? ICBTAG_FLAG_STICKY : 0) |
1922 			(le16_to_cpu(fe->icbTag.flags) &
1923 				~(ICBTAG_FLAG_AD_MASK | ICBTAG_FLAG_SETUID |
1924 				ICBTAG_FLAG_SETGID | ICBTAG_FLAG_STICKY));
1925 
1926 	fe->icbTag.flags = cpu_to_le16(icbflags);
1927 	if (sbi->s_udfrev >= 0x0200)
1928 		fe->descTag.descVersion = cpu_to_le16(3);
1929 	else
1930 		fe->descTag.descVersion = cpu_to_le16(2);
1931 	fe->descTag.tagSerialNum = cpu_to_le16(sbi->s_serial_number);
1932 	fe->descTag.tagLocation = cpu_to_le32(
1933 					iinfo->i_location.logicalBlockNum);
1934 	crclen += iinfo->i_lenEAttr + iinfo->i_lenAlloc - sizeof(struct tag);
1935 	fe->descTag.descCRCLength = cpu_to_le16(crclen);
1936 	fe->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)fe + sizeof(struct tag),
1937 						  crclen));
1938 	fe->descTag.tagChecksum = udf_tag_checksum(&fe->descTag);
1939 
1940 	set_buffer_uptodate(bh);
1941 	unlock_buffer(bh);
1942 
1943 	/* write the data blocks */
1944 	mark_buffer_dirty(bh);
1945 	brelse(bh);
1946 	set_inode_metadata_writeback(inode);
1947 
1948 	return 0;
1949 }
1950 
1951 struct inode *__udf_iget(struct super_block *sb, struct kernel_lb_addr *ino,
1952 			 bool hidden_inode)
1953 {
1954 	unsigned long block = udf_get_lb_pblock(sb, ino, 0);
1955 	struct inode *inode = iget_locked(sb, block);
1956 	int err;
1957 
1958 	if (!inode)
1959 		return ERR_PTR(-ENOMEM);
1960 
1961 	if (!(inode_state_read_once(inode) & I_NEW)) {
1962 		if (UDF_I(inode)->i_hidden != hidden_inode) {
1963 			iput(inode);
1964 			return ERR_PTR(-EFSCORRUPTED);
1965 		}
1966 		return inode;
1967 	}
1968 
1969 	memcpy(&UDF_I(inode)->i_location, ino, sizeof(struct kernel_lb_addr));
1970 	err = udf_read_inode(inode, hidden_inode);
1971 	if (err < 0) {
1972 		iget_failed(inode);
1973 		return ERR_PTR(err);
1974 	}
1975 	unlock_new_inode(inode);
1976 
1977 	return inode;
1978 }
1979 
1980 int udf_setup_indirect_aext(struct inode *inode, udf_pblk_t block,
1981 			    struct extent_position *epos)
1982 {
1983 	struct super_block *sb = inode->i_sb;
1984 	struct buffer_head *bh;
1985 	struct allocExtDesc *aed;
1986 	struct extent_position nepos;
1987 	struct kernel_lb_addr neloc;
1988 	int ver, adsize;
1989 	int err = 0;
1990 
1991 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
1992 		adsize = sizeof(struct short_ad);
1993 	else if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_LONG)
1994 		adsize = sizeof(struct long_ad);
1995 	else
1996 		return -EIO;
1997 
1998 	neloc.logicalBlockNum = block;
1999 	neloc.partitionReferenceNum = epos->block.partitionReferenceNum;
2000 
2001 	bh = sb_getblk(sb, udf_get_lb_pblock(sb, &neloc, 0));
2002 	if (!bh)
2003 		return -EIO;
2004 	lock_buffer(bh);
2005 	memset(bh->b_data, 0x00, sb->s_blocksize);
2006 	set_buffer_uptodate(bh);
2007 	unlock_buffer(bh);
2008 	mmb_mark_buffer_dirty(bh, &UDF_I(inode)->i_metadata_bhs);
2009 
2010 	aed = (struct allocExtDesc *)(bh->b_data);
2011 	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT)) {
2012 		aed->previousAllocExtLocation =
2013 				cpu_to_le32(epos->block.logicalBlockNum);
2014 	}
2015 	aed->lengthAllocDescs = cpu_to_le32(0);
2016 	if (UDF_SB(sb)->s_udfrev >= 0x0200)
2017 		ver = 3;
2018 	else
2019 		ver = 2;
2020 	udf_new_tag(bh->b_data, TAG_IDENT_AED, ver, 1, block,
2021 		    sizeof(struct tag));
2022 
2023 	nepos.block = neloc;
2024 	nepos.offset = sizeof(struct allocExtDesc);
2025 	nepos.bh = bh;
2026 
2027 	/*
2028 	 * Do we have to copy current last extent to make space for indirect
2029 	 * one?
2030 	 */
2031 	if (epos->offset + adsize > sb->s_blocksize) {
2032 		struct kernel_lb_addr cp_loc;
2033 		uint32_t cp_len;
2034 		int8_t cp_type;
2035 
2036 		epos->offset -= adsize;
2037 		err = udf_current_aext(inode, epos, &cp_loc, &cp_len, &cp_type, 0);
2038 		if (err <= 0)
2039 			goto err_out;
2040 		cp_len |= ((uint32_t)cp_type) << 30;
2041 
2042 		__udf_add_aext(inode, &nepos, &cp_loc, cp_len, 1);
2043 		udf_write_aext(inode, epos, &nepos.block,
2044 			       sb->s_blocksize | EXT_NEXT_EXTENT_ALLOCDESCS, 0);
2045 	} else {
2046 		__udf_add_aext(inode, epos, &nepos.block,
2047 			       sb->s_blocksize | EXT_NEXT_EXTENT_ALLOCDESCS, 0);
2048 	}
2049 
2050 	brelse(epos->bh);
2051 	*epos = nepos;
2052 
2053 	return 0;
2054 err_out:
2055 	brelse(bh);
2056 	return err;
2057 }
2058 
2059 /*
2060  * Append extent at the given position - should be the first free one in inode
2061  * / indirect extent. This function assumes there is enough space in the inode
2062  * or indirect extent. Use udf_add_aext() if you didn't check for this before.
2063  */
2064 int __udf_add_aext(struct inode *inode, struct extent_position *epos,
2065 		   struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2066 {
2067 	struct udf_inode_info *iinfo = UDF_I(inode);
2068 	struct allocExtDesc *aed;
2069 	int adsize;
2070 
2071 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2072 		adsize = sizeof(struct short_ad);
2073 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2074 		adsize = sizeof(struct long_ad);
2075 	else
2076 		return -EIO;
2077 
2078 	if (!epos->bh) {
2079 		WARN_ON(iinfo->i_lenAlloc !=
2080 			epos->offset - udf_file_entry_alloc_offset(inode));
2081 	} else {
2082 		aed = (struct allocExtDesc *)epos->bh->b_data;
2083 		WARN_ON(le32_to_cpu(aed->lengthAllocDescs) !=
2084 			epos->offset - sizeof(struct allocExtDesc));
2085 		WARN_ON(epos->offset + adsize > inode->i_sb->s_blocksize);
2086 	}
2087 
2088 	udf_write_aext(inode, epos, eloc, elen, inc);
2089 
2090 	if (!epos->bh) {
2091 		iinfo->i_lenAlloc += adsize;
2092 		mark_inode_dirty(inode);
2093 	} else {
2094 		aed = (struct allocExtDesc *)epos->bh->b_data;
2095 		le32_add_cpu(&aed->lengthAllocDescs, adsize);
2096 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2097 				UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2098 			udf_update_tag(epos->bh->b_data,
2099 					epos->offset + (inc ? 0 : adsize));
2100 		else
2101 			udf_update_tag(epos->bh->b_data,
2102 					sizeof(struct allocExtDesc));
2103 		mmb_mark_buffer_dirty(epos->bh, &iinfo->i_metadata_bhs);
2104 	}
2105 
2106 	return 0;
2107 }
2108 
2109 /*
2110  * Append extent at given position - should be the first free one in inode
2111  * / indirect extent. Takes care of allocating and linking indirect blocks.
2112  */
2113 int udf_add_aext(struct inode *inode, struct extent_position *epos,
2114 		 struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2115 {
2116 	int adsize;
2117 	struct super_block *sb = inode->i_sb;
2118 
2119 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2120 		adsize = sizeof(struct short_ad);
2121 	else if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2122 		adsize = sizeof(struct long_ad);
2123 	else
2124 		return -EIO;
2125 
2126 	if (epos->offset + (2 * adsize) > sb->s_blocksize) {
2127 		int err;
2128 		udf_pblk_t new_block;
2129 
2130 		new_block = udf_new_block(sb, NULL,
2131 					  epos->block.partitionReferenceNum,
2132 					  epos->block.logicalBlockNum, &err);
2133 		if (!new_block)
2134 			return -ENOSPC;
2135 
2136 		err = udf_setup_indirect_aext(inode, new_block, epos);
2137 		if (err)
2138 			return err;
2139 	}
2140 
2141 	return __udf_add_aext(inode, epos, eloc, elen, inc);
2142 }
2143 
2144 void udf_write_aext(struct inode *inode, struct extent_position *epos,
2145 		    struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2146 {
2147 	int adsize;
2148 	uint8_t *ptr;
2149 	struct short_ad *sad;
2150 	struct long_ad *lad;
2151 	struct udf_inode_info *iinfo = UDF_I(inode);
2152 
2153 	if (!epos->bh)
2154 		ptr = iinfo->i_data + epos->offset -
2155 			udf_file_entry_alloc_offset(inode) +
2156 			iinfo->i_lenEAttr;
2157 	else
2158 		ptr = epos->bh->b_data + epos->offset;
2159 
2160 	switch (iinfo->i_alloc_type) {
2161 	case ICBTAG_FLAG_AD_SHORT:
2162 		sad = (struct short_ad *)ptr;
2163 		sad->extLength = cpu_to_le32(elen);
2164 		sad->extPosition = cpu_to_le32(eloc->logicalBlockNum);
2165 		adsize = sizeof(struct short_ad);
2166 		break;
2167 	case ICBTAG_FLAG_AD_LONG:
2168 		lad = (struct long_ad *)ptr;
2169 		lad->extLength = cpu_to_le32(elen);
2170 		lad->extLocation = cpu_to_lelb(*eloc);
2171 		memset(lad->impUse, 0x00, sizeof(lad->impUse));
2172 		adsize = sizeof(struct long_ad);
2173 		break;
2174 	default:
2175 		return;
2176 	}
2177 
2178 	if (epos->bh) {
2179 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2180 		    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201) {
2181 			struct allocExtDesc *aed =
2182 				(struct allocExtDesc *)epos->bh->b_data;
2183 			udf_update_tag(epos->bh->b_data,
2184 				       le32_to_cpu(aed->lengthAllocDescs) +
2185 				       sizeof(struct allocExtDesc));
2186 		}
2187 		mmb_mark_buffer_dirty(epos->bh, &iinfo->i_metadata_bhs);
2188 	} else {
2189 		mark_inode_dirty(inode);
2190 	}
2191 
2192 	if (inc)
2193 		epos->offset += adsize;
2194 }
2195 
2196 /*
2197  * Only 1 indirect extent in a row really makes sense but allow upto 16 in case
2198  * someone does some weird stuff.
2199  */
2200 #define UDF_MAX_INDIR_EXTS 16
2201 
2202 /*
2203  * Returns 1 on success, -errno on error, 0 on hit EOF.
2204  */
2205 int udf_next_aext(struct inode *inode, struct extent_position *epos,
2206 		  struct kernel_lb_addr *eloc, uint32_t *elen, int8_t *etype,
2207 		  int inc)
2208 {
2209 	unsigned int indirections = 0;
2210 	int ret = 0;
2211 	udf_pblk_t block;
2212 
2213 	while (1) {
2214 		ret = udf_current_aext(inode, epos, eloc, elen,
2215 				       etype, inc);
2216 		if (ret <= 0)
2217 			return ret;
2218 		if (*etype != (EXT_NEXT_EXTENT_ALLOCDESCS >> 30))
2219 			return ret;
2220 
2221 		if (++indirections > UDF_MAX_INDIR_EXTS) {
2222 			udf_err(inode->i_sb,
2223 				"too many indirect extents in inode %llu\n",
2224 				inode->i_ino);
2225 			return -EFSCORRUPTED;
2226 		}
2227 
2228 		epos->block = *eloc;
2229 		epos->offset = sizeof(struct allocExtDesc);
2230 		brelse(epos->bh);
2231 		block = udf_get_lb_pblock(inode->i_sb, &epos->block, 0);
2232 		epos->bh = sb_bread(inode->i_sb, block);
2233 		if (!epos->bh) {
2234 			udf_debug("reading block %u failed!\n", block);
2235 			return -EIO;
2236 		}
2237 	}
2238 }
2239 
2240 /*
2241  * Returns 1 on success, -errno on error, 0 on hit EOF.
2242  */
2243 int udf_current_aext(struct inode *inode, struct extent_position *epos,
2244 		     struct kernel_lb_addr *eloc, uint32_t *elen, int8_t *etype,
2245 		     int inc)
2246 {
2247 	int alen;
2248 	uint8_t *ptr;
2249 	struct short_ad *sad;
2250 	struct long_ad *lad;
2251 	struct udf_inode_info *iinfo = UDF_I(inode);
2252 
2253 	if (!epos->bh) {
2254 		if (!epos->offset)
2255 			epos->offset = udf_file_entry_alloc_offset(inode);
2256 		ptr = iinfo->i_data + epos->offset -
2257 			udf_file_entry_alloc_offset(inode) +
2258 			iinfo->i_lenEAttr;
2259 		alen = udf_file_entry_alloc_offset(inode) +
2260 							iinfo->i_lenAlloc;
2261 	} else {
2262 		struct allocExtDesc *header =
2263 			(struct allocExtDesc *)epos->bh->b_data;
2264 
2265 		if (!epos->offset)
2266 			epos->offset = sizeof(struct allocExtDesc);
2267 		ptr = epos->bh->b_data + epos->offset;
2268 		if (check_add_overflow(sizeof(struct allocExtDesc),
2269 				le32_to_cpu(header->lengthAllocDescs), &alen))
2270 			return -1;
2271 
2272 		if (alen > epos->bh->b_size)
2273 			return -1;
2274 	}
2275 
2276 	switch (iinfo->i_alloc_type) {
2277 	case ICBTAG_FLAG_AD_SHORT:
2278 		sad = udf_get_fileshortad(ptr, alen, &epos->offset, inc);
2279 		if (!sad)
2280 			return 0;
2281 		*etype = le32_to_cpu(sad->extLength) >> 30;
2282 		eloc->logicalBlockNum = le32_to_cpu(sad->extPosition);
2283 		eloc->partitionReferenceNum =
2284 				iinfo->i_location.partitionReferenceNum;
2285 		*elen = le32_to_cpu(sad->extLength) & UDF_EXTENT_LENGTH_MASK;
2286 		break;
2287 	case ICBTAG_FLAG_AD_LONG:
2288 		lad = udf_get_filelongad(ptr, alen, &epos->offset, inc);
2289 		if (!lad)
2290 			return 0;
2291 		*etype = le32_to_cpu(lad->extLength) >> 30;
2292 		*eloc = lelb_to_cpu(lad->extLocation);
2293 		*elen = le32_to_cpu(lad->extLength) & UDF_EXTENT_LENGTH_MASK;
2294 		break;
2295 	default:
2296 		udf_debug("alloc_type = %u unsupported\n", iinfo->i_alloc_type);
2297 		return -EINVAL;
2298 	}
2299 
2300 	return 1;
2301 }
2302 
2303 static int udf_insert_aext(struct inode *inode, struct extent_position epos,
2304 			   struct kernel_lb_addr neloc, uint32_t nelen)
2305 {
2306 	struct kernel_lb_addr oeloc;
2307 	uint32_t oelen;
2308 	int8_t etype;
2309 	int ret;
2310 
2311 	if (epos.bh)
2312 		get_bh(epos.bh);
2313 
2314 	while (1) {
2315 		ret = udf_next_aext(inode, &epos, &oeloc, &oelen, &etype, 0);
2316 		if (ret <= 0)
2317 			break;
2318 		udf_write_aext(inode, &epos, &neloc, nelen, 1);
2319 		neloc = oeloc;
2320 		nelen = (etype << 30) | oelen;
2321 	}
2322 	if (ret == 0)
2323 		ret = udf_add_aext(inode, &epos, &neloc, nelen, 1);
2324 	brelse(epos.bh);
2325 
2326 	return ret;
2327 }
2328 
2329 int8_t udf_delete_aext(struct inode *inode, struct extent_position epos)
2330 {
2331 	struct extent_position oepos;
2332 	int adsize;
2333 	int8_t etype;
2334 	struct allocExtDesc *aed;
2335 	struct udf_inode_info *iinfo;
2336 	struct kernel_lb_addr eloc;
2337 	uint32_t elen;
2338 	int ret;
2339 
2340 	if (epos.bh) {
2341 		get_bh(epos.bh);
2342 		get_bh(epos.bh);
2343 	}
2344 
2345 	iinfo = UDF_I(inode);
2346 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2347 		adsize = sizeof(struct short_ad);
2348 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2349 		adsize = sizeof(struct long_ad);
2350 	else
2351 		adsize = 0;
2352 
2353 	oepos = epos;
2354 	if (udf_next_aext(inode, &epos, &eloc, &elen, &etype, 1) <= 0)
2355 		return -1;
2356 
2357 	while (1) {
2358 		ret = udf_next_aext(inode, &epos, &eloc, &elen, &etype, 1);
2359 		if (ret < 0) {
2360 			brelse(epos.bh);
2361 			brelse(oepos.bh);
2362 			return -1;
2363 		}
2364 		if (ret == 0)
2365 			break;
2366 		udf_write_aext(inode, &oepos, &eloc, (etype << 30) | elen, 1);
2367 		if (oepos.bh != epos.bh) {
2368 			oepos.block = epos.block;
2369 			brelse(oepos.bh);
2370 			get_bh(epos.bh);
2371 			oepos.bh = epos.bh;
2372 			oepos.offset = epos.offset - adsize;
2373 		}
2374 	}
2375 	memset(&eloc, 0x00, sizeof(struct kernel_lb_addr));
2376 	elen = 0;
2377 
2378 	if (epos.bh != oepos.bh) {
2379 		udf_free_blocks(inode->i_sb, inode, &epos.block, 0, 1);
2380 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2381 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2382 		if (!oepos.bh) {
2383 			iinfo->i_lenAlloc -= (adsize * 2);
2384 			mark_inode_dirty(inode);
2385 		} else {
2386 			aed = (struct allocExtDesc *)oepos.bh->b_data;
2387 			le32_add_cpu(&aed->lengthAllocDescs, -(2 * adsize));
2388 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2389 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2390 				udf_update_tag(oepos.bh->b_data,
2391 						oepos.offset - (2 * adsize));
2392 			else
2393 				udf_update_tag(oepos.bh->b_data,
2394 						sizeof(struct allocExtDesc));
2395 			mmb_mark_buffer_dirty(oepos.bh, &iinfo->i_metadata_bhs);
2396 		}
2397 	} else {
2398 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2399 		if (!oepos.bh) {
2400 			iinfo->i_lenAlloc -= adsize;
2401 			mark_inode_dirty(inode);
2402 		} else {
2403 			aed = (struct allocExtDesc *)oepos.bh->b_data;
2404 			le32_add_cpu(&aed->lengthAllocDescs, -adsize);
2405 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2406 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2407 				udf_update_tag(oepos.bh->b_data,
2408 						epos.offset - adsize);
2409 			else
2410 				udf_update_tag(oepos.bh->b_data,
2411 						sizeof(struct allocExtDesc));
2412 			mmb_mark_buffer_dirty(oepos.bh, &iinfo->i_metadata_bhs);
2413 		}
2414 	}
2415 
2416 	brelse(epos.bh);
2417 	brelse(oepos.bh);
2418 
2419 	return (elen >> 30);
2420 }
2421 
2422 /*
2423  * Returns 1 on success, -errno on error, 0 on hit EOF.
2424  */
2425 int inode_bmap(struct inode *inode, sector_t block, struct extent_position *pos,
2426 	       struct kernel_lb_addr *eloc, uint32_t *elen, sector_t *offset,
2427 	       int8_t *etype)
2428 {
2429 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
2430 	loff_t lbcount = 0, bcount = (loff_t) block << blocksize_bits;
2431 	struct udf_inode_info *iinfo;
2432 	int err = 0;
2433 
2434 	iinfo = UDF_I(inode);
2435 	if (!udf_read_extent_cache(inode, bcount, &lbcount, pos)) {
2436 		pos->offset = 0;
2437 		pos->block = iinfo->i_location;
2438 		pos->bh = NULL;
2439 	}
2440 	*elen = 0;
2441 	do {
2442 		err = udf_next_aext(inode, pos, eloc, elen, etype, 1);
2443 		if (err <= 0) {
2444 			if (err == 0) {
2445 				*offset = (bcount - lbcount) >> blocksize_bits;
2446 				iinfo->i_lenExtents = lbcount;
2447 			}
2448 			return err;
2449 		}
2450 		lbcount += *elen;
2451 	} while (lbcount <= bcount);
2452 	/* update extent cache */
2453 	udf_update_extent_cache(inode, lbcount - *elen, pos);
2454 	*offset = (bcount + *elen - lbcount) >> blocksize_bits;
2455 
2456 	return 1;
2457 }
2458