xref: /linux/fs/udf/inode.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
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 ret;
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 		int8_t etype;
420 
421 		down_read(&iinfo->i_data_sem);
422 		ret = inode_bmap(inode, map->lblk, &epos, &eloc, &elen, &offset,
423 				 &etype);
424 		if (ret < 0)
425 			goto out_read;
426 		if (ret > 0 && etype == (EXT_RECORDED_ALLOCATED >> 30)) {
427 			map->pblk = udf_get_lb_pblock(inode->i_sb, &eloc,
428 							offset);
429 			map->oflags |= UDF_BLK_MAPPED;
430 			ret = 0;
431 		}
432 out_read:
433 		up_read(&iinfo->i_data_sem);
434 		brelse(epos.bh);
435 
436 		return ret;
437 	}
438 
439 	down_write(&iinfo->i_data_sem);
440 	/*
441 	 * Block beyond EOF and prealloc extents? Just discard preallocation
442 	 * as it is not useful and complicates things.
443 	 */
444 	if (((loff_t)map->lblk) << inode->i_blkbits >= iinfo->i_lenExtents)
445 		udf_discard_prealloc(inode);
446 	udf_clear_extent_cache(inode);
447 	ret = inode_getblk(inode, map);
448 	up_write(&iinfo->i_data_sem);
449 	return ret;
450 }
451 
452 static int __udf_get_block(struct inode *inode, sector_t block,
453 			   struct buffer_head *bh_result, int flags)
454 {
455 	int err;
456 	struct udf_map_rq map = {
457 		.lblk = block,
458 		.iflags = flags,
459 	};
460 
461 	err = udf_map_block(inode, &map);
462 	if (err < 0)
463 		return err;
464 	if (map.oflags & UDF_BLK_MAPPED) {
465 		map_bh(bh_result, inode->i_sb, map.pblk);
466 		if (map.oflags & UDF_BLK_NEW)
467 			set_buffer_new(bh_result);
468 	}
469 	return 0;
470 }
471 
472 int udf_get_block(struct inode *inode, sector_t block,
473 		  struct buffer_head *bh_result, int create)
474 {
475 	int flags = create ? UDF_MAP_CREATE : 0;
476 
477 	/*
478 	 * We preallocate blocks only for regular files. It also makes sense
479 	 * for directories but there's a problem when to drop the
480 	 * preallocation. We might use some delayed work for that but I feel
481 	 * it's overengineering for a filesystem like UDF.
482 	 */
483 	if (!S_ISREG(inode->i_mode))
484 		flags |= UDF_MAP_NOPREALLOC;
485 	return __udf_get_block(inode, block, bh_result, flags);
486 }
487 
488 /*
489  * We shouldn't be allocating blocks on page writeback since we allocate them
490  * on page fault. We can spot dirty buffers without allocated blocks though
491  * when truncate expands file. These however don't have valid data so we can
492  * safely ignore them. So never allocate blocks from page writeback.
493  */
494 static int udf_get_block_wb(struct inode *inode, sector_t block,
495 			    struct buffer_head *bh_result, int create)
496 {
497 	return __udf_get_block(inode, block, bh_result, 0);
498 }
499 
500 /* Extend the file with new blocks totaling 'new_block_bytes',
501  * return the number of extents added
502  */
503 static int udf_do_extend_file(struct inode *inode,
504 			      struct extent_position *last_pos,
505 			      struct kernel_long_ad *last_ext,
506 			      loff_t new_block_bytes)
507 {
508 	uint32_t add;
509 	int count = 0, fake = !(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
510 	struct super_block *sb = inode->i_sb;
511 	struct udf_inode_info *iinfo;
512 	int err;
513 
514 	/* The previous extent is fake and we should not extend by anything
515 	 * - there's nothing to do... */
516 	if (!new_block_bytes && fake)
517 		return 0;
518 
519 	iinfo = UDF_I(inode);
520 	/* Round the last extent up to a multiple of block size */
521 	if (last_ext->extLength & (sb->s_blocksize - 1)) {
522 		last_ext->extLength =
523 			(last_ext->extLength & UDF_EXTENT_FLAG_MASK) |
524 			(((last_ext->extLength & UDF_EXTENT_LENGTH_MASK) +
525 			  sb->s_blocksize - 1) & ~(sb->s_blocksize - 1));
526 		iinfo->i_lenExtents =
527 			(iinfo->i_lenExtents + sb->s_blocksize - 1) &
528 			~(sb->s_blocksize - 1);
529 	}
530 
531 	add = 0;
532 	/* Can we merge with the previous extent? */
533 	if ((last_ext->extLength & UDF_EXTENT_FLAG_MASK) ==
534 					EXT_NOT_RECORDED_NOT_ALLOCATED) {
535 		add = (1 << 30) - sb->s_blocksize -
536 			(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
537 		if (add > new_block_bytes)
538 			add = new_block_bytes;
539 		new_block_bytes -= add;
540 		last_ext->extLength += add;
541 	}
542 
543 	if (fake) {
544 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
545 				   last_ext->extLength, 1);
546 		if (err < 0)
547 			goto out_err;
548 		count++;
549 	} else {
550 		struct kernel_lb_addr tmploc;
551 		uint32_t tmplen;
552 		int8_t tmptype;
553 
554 		udf_write_aext(inode, last_pos, &last_ext->extLocation,
555 				last_ext->extLength, 1);
556 
557 		/*
558 		 * We've rewritten the last extent. If we are going to add
559 		 * more extents, we may need to enter possible following
560 		 * empty indirect extent.
561 		 */
562 		if (new_block_bytes) {
563 			err = udf_next_aext(inode, last_pos, &tmploc, &tmplen,
564 					    &tmptype, 0);
565 			if (err < 0)
566 				goto out_err;
567 		}
568 	}
569 	iinfo->i_lenExtents += add;
570 
571 	/* Managed to do everything necessary? */
572 	if (!new_block_bytes)
573 		goto out;
574 
575 	/* All further extents will be NOT_RECORDED_NOT_ALLOCATED */
576 	last_ext->extLocation.logicalBlockNum = 0;
577 	last_ext->extLocation.partitionReferenceNum = 0;
578 	add = (1 << 30) - sb->s_blocksize;
579 	last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED | add;
580 
581 	/* Create enough extents to cover the whole hole */
582 	while (new_block_bytes > add) {
583 		new_block_bytes -= add;
584 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
585 				   last_ext->extLength, 1);
586 		if (err)
587 			goto out_err;
588 		iinfo->i_lenExtents += add;
589 		count++;
590 	}
591 	if (new_block_bytes) {
592 		last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
593 			new_block_bytes;
594 		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
595 				   last_ext->extLength, 1);
596 		if (err)
597 			goto out_err;
598 		iinfo->i_lenExtents += new_block_bytes;
599 		count++;
600 	}
601 
602 out:
603 	/* last_pos should point to the last written extent... */
604 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
605 		last_pos->offset -= sizeof(struct short_ad);
606 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
607 		last_pos->offset -= sizeof(struct long_ad);
608 	else
609 		return -EIO;
610 
611 	return count;
612 out_err:
613 	/* Remove extents we've created so far */
614 	udf_clear_extent_cache(inode);
615 	udf_truncate_extents(inode);
616 	return err;
617 }
618 
619 /* Extend the final block of the file to final_block_len bytes */
620 static void udf_do_extend_final_block(struct inode *inode,
621 				      struct extent_position *last_pos,
622 				      struct kernel_long_ad *last_ext,
623 				      uint32_t new_elen)
624 {
625 	uint32_t added_bytes;
626 
627 	/*
628 	 * Extent already large enough? It may be already rounded up to block
629 	 * size...
630 	 */
631 	if (new_elen <= (last_ext->extLength & UDF_EXTENT_LENGTH_MASK))
632 		return;
633 	added_bytes = new_elen - (last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
634 	last_ext->extLength += added_bytes;
635 	UDF_I(inode)->i_lenExtents += added_bytes;
636 
637 	udf_write_aext(inode, last_pos, &last_ext->extLocation,
638 			last_ext->extLength, 1);
639 }
640 
641 static int udf_extend_file(struct inode *inode, loff_t newsize)
642 {
643 
644 	struct extent_position epos;
645 	struct kernel_lb_addr eloc;
646 	uint32_t elen;
647 	int8_t etype;
648 	struct super_block *sb = inode->i_sb;
649 	sector_t first_block = newsize >> sb->s_blocksize_bits, offset;
650 	loff_t new_elen;
651 	int adsize;
652 	struct udf_inode_info *iinfo = UDF_I(inode);
653 	struct kernel_long_ad extent;
654 	int err = 0;
655 	bool within_last_ext;
656 
657 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
658 		adsize = sizeof(struct short_ad);
659 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
660 		adsize = sizeof(struct long_ad);
661 	else
662 		BUG();
663 
664 	down_write(&iinfo->i_data_sem);
665 	/*
666 	 * When creating hole in file, just don't bother with preserving
667 	 * preallocation. It likely won't be very useful anyway.
668 	 */
669 	udf_discard_prealloc(inode);
670 
671 	err = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset, &etype);
672 	if (err < 0)
673 		goto out;
674 	within_last_ext = (err == 1);
675 	/* We don't expect extents past EOF... */
676 	WARN_ON_ONCE(within_last_ext &&
677 		     elen > ((loff_t)offset + 1) << inode->i_blkbits);
678 
679 	if ((!epos.bh && epos.offset == udf_file_entry_alloc_offset(inode)) ||
680 	    (epos.bh && epos.offset == sizeof(struct allocExtDesc))) {
681 		/* File has no extents at all or has empty last
682 		 * indirect extent! Create a fake extent... */
683 		extent.extLocation.logicalBlockNum = 0;
684 		extent.extLocation.partitionReferenceNum = 0;
685 		extent.extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
686 	} else {
687 		epos.offset -= adsize;
688 		err = udf_next_aext(inode, &epos, &extent.extLocation,
689 				    &extent.extLength, &etype, 0);
690 		if (err <= 0)
691 			goto out;
692 		extent.extLength |= etype << 30;
693 	}
694 
695 	new_elen = ((loff_t)offset << inode->i_blkbits) |
696 					(newsize & (sb->s_blocksize - 1));
697 
698 	/* File has extent covering the new size (could happen when extending
699 	 * inside a block)?
700 	 */
701 	if (within_last_ext) {
702 		/* Extending file within the last file block */
703 		udf_do_extend_final_block(inode, &epos, &extent, new_elen);
704 	} else {
705 		err = udf_do_extend_file(inode, &epos, &extent, new_elen);
706 	}
707 
708 	if (err < 0)
709 		goto out;
710 	err = 0;
711 out:
712 	brelse(epos.bh);
713 	up_write(&iinfo->i_data_sem);
714 	return err;
715 }
716 
717 static int inode_getblk(struct inode *inode, struct udf_map_rq *map)
718 {
719 	struct kernel_long_ad laarr[EXTENT_MERGE_SIZE];
720 	struct extent_position prev_epos, cur_epos, next_epos;
721 	int count = 0, startnum = 0, endnum = 0;
722 	uint32_t elen = 0, tmpelen;
723 	struct kernel_lb_addr eloc, tmpeloc;
724 	int c = 1;
725 	loff_t lbcount = 0, b_off = 0;
726 	udf_pblk_t newblocknum;
727 	sector_t offset = 0;
728 	int8_t etype, tmpetype;
729 	struct udf_inode_info *iinfo = UDF_I(inode);
730 	udf_pblk_t goal = 0, pgoal = iinfo->i_location.logicalBlockNum;
731 	int lastblock = 0;
732 	bool isBeyondEOF = false;
733 	int ret = 0;
734 
735 	prev_epos.offset = udf_file_entry_alloc_offset(inode);
736 	prev_epos.block = iinfo->i_location;
737 	prev_epos.bh = NULL;
738 	cur_epos = next_epos = prev_epos;
739 	b_off = (loff_t)map->lblk << inode->i_sb->s_blocksize_bits;
740 
741 	/* find the extent which contains the block we are looking for.
742 	   alternate between laarr[0] and laarr[1] for locations of the
743 	   current extent, and the previous extent */
744 	do {
745 		if (prev_epos.bh != cur_epos.bh) {
746 			brelse(prev_epos.bh);
747 			get_bh(cur_epos.bh);
748 			prev_epos.bh = cur_epos.bh;
749 		}
750 		if (cur_epos.bh != next_epos.bh) {
751 			brelse(cur_epos.bh);
752 			get_bh(next_epos.bh);
753 			cur_epos.bh = next_epos.bh;
754 		}
755 
756 		lbcount += elen;
757 
758 		prev_epos.block = cur_epos.block;
759 		cur_epos.block = next_epos.block;
760 
761 		prev_epos.offset = cur_epos.offset;
762 		cur_epos.offset = next_epos.offset;
763 
764 		ret = udf_next_aext(inode, &next_epos, &eloc, &elen, &etype, 1);
765 		if (ret < 0) {
766 			goto out_free;
767 		} else if (ret == 0) {
768 			isBeyondEOF = true;
769 			break;
770 		}
771 
772 		c = !c;
773 
774 		laarr[c].extLength = (etype << 30) | elen;
775 		laarr[c].extLocation = eloc;
776 
777 		if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
778 			pgoal = eloc.logicalBlockNum +
779 				((elen + inode->i_sb->s_blocksize - 1) >>
780 				 inode->i_sb->s_blocksize_bits);
781 
782 		count++;
783 	} while (lbcount + elen <= b_off);
784 
785 	b_off -= lbcount;
786 	offset = b_off >> inode->i_sb->s_blocksize_bits;
787 	/*
788 	 * Move prev_epos and cur_epos into indirect extent if we are at
789 	 * the pointer to it
790 	 */
791 	ret = udf_next_aext(inode, &prev_epos, &tmpeloc, &tmpelen, &tmpetype, 0);
792 	if (ret < 0)
793 		goto out_free;
794 	ret = udf_next_aext(inode, &cur_epos, &tmpeloc, &tmpelen, &tmpetype, 0);
795 	if (ret < 0)
796 		goto out_free;
797 
798 	/* if the extent is allocated and recorded, return the block
799 	   if the extent is not a multiple of the blocksize, round up */
800 
801 	if (!isBeyondEOF && etype == (EXT_RECORDED_ALLOCATED >> 30)) {
802 		if (elen & (inode->i_sb->s_blocksize - 1)) {
803 			elen = EXT_RECORDED_ALLOCATED |
804 				((elen + inode->i_sb->s_blocksize - 1) &
805 				 ~(inode->i_sb->s_blocksize - 1));
806 			iinfo->i_lenExtents =
807 				ALIGN(iinfo->i_lenExtents,
808 				      inode->i_sb->s_blocksize);
809 			udf_write_aext(inode, &cur_epos, &eloc, elen, 1);
810 		}
811 		map->oflags = UDF_BLK_MAPPED;
812 		map->pblk = udf_get_lb_pblock(inode->i_sb, &eloc, offset);
813 		goto out_free;
814 	}
815 
816 	/* Are we beyond EOF and preallocated extent? */
817 	if (isBeyondEOF) {
818 		loff_t hole_len;
819 
820 		if (count) {
821 			if (c)
822 				laarr[0] = laarr[1];
823 			startnum = 1;
824 		} else {
825 			/* Create a fake extent when there's not one */
826 			memset(&laarr[0].extLocation, 0x00,
827 				sizeof(struct kernel_lb_addr));
828 			laarr[0].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
829 			/* Will udf_do_extend_file() create real extent from
830 			   a fake one? */
831 			startnum = (offset > 0);
832 		}
833 		/* Create extents for the hole between EOF and offset */
834 		hole_len = (loff_t)offset << inode->i_blkbits;
835 		ret = udf_do_extend_file(inode, &prev_epos, laarr, hole_len);
836 		if (ret < 0)
837 			goto out_free;
838 		c = 0;
839 		offset = 0;
840 		count += ret;
841 		/*
842 		 * Is there any real extent? - otherwise we overwrite the fake
843 		 * one...
844 		 */
845 		if (count)
846 			c = !c;
847 		laarr[c].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
848 			inode->i_sb->s_blocksize;
849 		memset(&laarr[c].extLocation, 0x00,
850 			sizeof(struct kernel_lb_addr));
851 		count++;
852 		endnum = c + 1;
853 		lastblock = 1;
854 	} else {
855 		endnum = startnum = ((count > 2) ? 2 : count);
856 
857 		/* if the current extent is in position 0,
858 		   swap it with the previous */
859 		if (!c && count != 1) {
860 			laarr[2] = laarr[0];
861 			laarr[0] = laarr[1];
862 			laarr[1] = laarr[2];
863 			c = 1;
864 		}
865 
866 		/* if the current block is located in an extent,
867 		   read the next extent */
868 		ret = udf_next_aext(inode, &next_epos, &eloc, &elen, &etype, 0);
869 		if (ret > 0) {
870 			laarr[c + 1].extLength = (etype << 30) | elen;
871 			laarr[c + 1].extLocation = eloc;
872 			count++;
873 			startnum++;
874 			endnum++;
875 		} else if (ret == 0)
876 			lastblock = 1;
877 		else
878 			goto out_free;
879 	}
880 
881 	/* if the current extent is not recorded but allocated, get the
882 	 * block in the extent corresponding to the requested block */
883 	if ((laarr[c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30))
884 		newblocknum = laarr[c].extLocation.logicalBlockNum + offset;
885 	else { /* otherwise, allocate a new block */
886 		if (iinfo->i_next_alloc_block == map->lblk)
887 			goal = iinfo->i_next_alloc_goal;
888 
889 		if (!goal) {
890 			if (!(goal = pgoal)) /* XXX: what was intended here? */
891 				goal = iinfo->i_location.logicalBlockNum + 1;
892 		}
893 
894 		newblocknum = udf_new_block(inode->i_sb, inode,
895 				iinfo->i_location.partitionReferenceNum,
896 				goal, &ret);
897 		if (!newblocknum)
898 			goto out_free;
899 		if (isBeyondEOF)
900 			iinfo->i_lenExtents += inode->i_sb->s_blocksize;
901 	}
902 
903 	/* if the extent the requsted block is located in contains multiple
904 	 * blocks, split the extent into at most three extents. blocks prior
905 	 * to requested block, requested block, and blocks after requested
906 	 * block */
907 	udf_split_extents(inode, &c, offset, newblocknum, laarr, &endnum);
908 
909 	if (!(map->iflags & UDF_MAP_NOPREALLOC))
910 		udf_prealloc_extents(inode, c, lastblock, laarr, &endnum);
911 
912 	/* merge any continuous blocks in laarr */
913 	udf_merge_extents(inode, laarr, &endnum);
914 
915 	/* write back the new extents, inserting new extents if the new number
916 	 * of extents is greater than the old number, and deleting extents if
917 	 * the new number of extents is less than the old number */
918 	ret = udf_update_extents(inode, laarr, startnum, endnum, &prev_epos);
919 	if (ret < 0)
920 		goto out_free;
921 
922 	map->pblk = udf_get_pblock(inode->i_sb, newblocknum,
923 				iinfo->i_location.partitionReferenceNum, 0);
924 	if (!map->pblk) {
925 		ret = -EFSCORRUPTED;
926 		goto out_free;
927 	}
928 	map->oflags = UDF_BLK_NEW | UDF_BLK_MAPPED;
929 	iinfo->i_next_alloc_block = map->lblk + 1;
930 	iinfo->i_next_alloc_goal = newblocknum + 1;
931 	inode_set_ctime_current(inode);
932 
933 	if (IS_SYNC(inode))
934 		udf_sync_inode(inode);
935 	else
936 		mark_inode_dirty(inode);
937 	ret = 0;
938 out_free:
939 	brelse(prev_epos.bh);
940 	brelse(cur_epos.bh);
941 	brelse(next_epos.bh);
942 	return ret;
943 }
944 
945 static void udf_split_extents(struct inode *inode, int *c, int offset,
946 			       udf_pblk_t newblocknum,
947 			       struct kernel_long_ad *laarr, int *endnum)
948 {
949 	unsigned long blocksize = inode->i_sb->s_blocksize;
950 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
951 
952 	if ((laarr[*c].extLength >> 30) == (EXT_NOT_RECORDED_ALLOCATED >> 30) ||
953 	    (laarr[*c].extLength >> 30) ==
954 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
955 		int curr = *c;
956 		int blen = ((laarr[curr].extLength & UDF_EXTENT_LENGTH_MASK) +
957 			    blocksize - 1) >> blocksize_bits;
958 		int8_t etype = (laarr[curr].extLength >> 30);
959 
960 		if (blen == 1)
961 			;
962 		else if (!offset || blen == offset + 1) {
963 			laarr[curr + 2] = laarr[curr + 1];
964 			laarr[curr + 1] = laarr[curr];
965 		} else {
966 			laarr[curr + 3] = laarr[curr + 1];
967 			laarr[curr + 2] = laarr[curr + 1] = laarr[curr];
968 		}
969 
970 		if (offset) {
971 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
972 				udf_free_blocks(inode->i_sb, inode,
973 						&laarr[curr].extLocation,
974 						0, offset);
975 				laarr[curr].extLength =
976 					EXT_NOT_RECORDED_NOT_ALLOCATED |
977 					(offset << blocksize_bits);
978 				laarr[curr].extLocation.logicalBlockNum = 0;
979 				laarr[curr].extLocation.
980 						partitionReferenceNum = 0;
981 			} else
982 				laarr[curr].extLength = (etype << 30) |
983 					(offset << blocksize_bits);
984 			curr++;
985 			(*c)++;
986 			(*endnum)++;
987 		}
988 
989 		laarr[curr].extLocation.logicalBlockNum = newblocknum;
990 		if (etype == (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
991 			laarr[curr].extLocation.partitionReferenceNum =
992 				UDF_I(inode)->i_location.partitionReferenceNum;
993 		laarr[curr].extLength = EXT_RECORDED_ALLOCATED |
994 			blocksize;
995 		curr++;
996 
997 		if (blen != offset + 1) {
998 			if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
999 				laarr[curr].extLocation.logicalBlockNum +=
1000 								offset + 1;
1001 			laarr[curr].extLength = (etype << 30) |
1002 				((blen - (offset + 1)) << blocksize_bits);
1003 			curr++;
1004 			(*endnum)++;
1005 		}
1006 	}
1007 }
1008 
1009 static void udf_prealloc_extents(struct inode *inode, int c, int lastblock,
1010 				 struct kernel_long_ad *laarr,
1011 				 int *endnum)
1012 {
1013 	int start, length = 0, currlength = 0, i;
1014 
1015 	if (*endnum >= (c + 1)) {
1016 		if (!lastblock)
1017 			return;
1018 		else
1019 			start = c;
1020 	} else {
1021 		if ((laarr[c + 1].extLength >> 30) ==
1022 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
1023 			start = c + 1;
1024 			length = currlength =
1025 				(((laarr[c + 1].extLength &
1026 					UDF_EXTENT_LENGTH_MASK) +
1027 				inode->i_sb->s_blocksize - 1) >>
1028 				inode->i_sb->s_blocksize_bits);
1029 		} else
1030 			start = c;
1031 	}
1032 
1033 	for (i = start + 1; i <= *endnum; i++) {
1034 		if (i == *endnum) {
1035 			if (lastblock)
1036 				length += UDF_DEFAULT_PREALLOC_BLOCKS;
1037 		} else if ((laarr[i].extLength >> 30) ==
1038 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) {
1039 			length += (((laarr[i].extLength &
1040 						UDF_EXTENT_LENGTH_MASK) +
1041 				    inode->i_sb->s_blocksize - 1) >>
1042 				    inode->i_sb->s_blocksize_bits);
1043 		} else
1044 			break;
1045 	}
1046 
1047 	if (length) {
1048 		int next = laarr[start].extLocation.logicalBlockNum +
1049 			(((laarr[start].extLength & UDF_EXTENT_LENGTH_MASK) +
1050 			  inode->i_sb->s_blocksize - 1) >>
1051 			  inode->i_sb->s_blocksize_bits);
1052 		int numalloc = udf_prealloc_blocks(inode->i_sb, inode,
1053 				laarr[start].extLocation.partitionReferenceNum,
1054 				next, (UDF_DEFAULT_PREALLOC_BLOCKS > length ?
1055 				length : UDF_DEFAULT_PREALLOC_BLOCKS) -
1056 				currlength);
1057 		if (numalloc) 	{
1058 			if (start == (c + 1))
1059 				laarr[start].extLength +=
1060 					(numalloc <<
1061 					 inode->i_sb->s_blocksize_bits);
1062 			else {
1063 				memmove(&laarr[c + 2], &laarr[c + 1],
1064 					sizeof(struct long_ad) * (*endnum - (c + 1)));
1065 				(*endnum)++;
1066 				laarr[c + 1].extLocation.logicalBlockNum = next;
1067 				laarr[c + 1].extLocation.partitionReferenceNum =
1068 					laarr[c].extLocation.
1069 							partitionReferenceNum;
1070 				laarr[c + 1].extLength =
1071 					EXT_NOT_RECORDED_ALLOCATED |
1072 					(numalloc <<
1073 					 inode->i_sb->s_blocksize_bits);
1074 				start = c + 1;
1075 			}
1076 
1077 			for (i = start + 1; numalloc && i < *endnum; i++) {
1078 				int elen = ((laarr[i].extLength &
1079 						UDF_EXTENT_LENGTH_MASK) +
1080 					    inode->i_sb->s_blocksize - 1) >>
1081 					    inode->i_sb->s_blocksize_bits;
1082 
1083 				if (elen > numalloc) {
1084 					laarr[i].extLength -=
1085 						(numalloc <<
1086 						 inode->i_sb->s_blocksize_bits);
1087 					numalloc = 0;
1088 				} else {
1089 					numalloc -= elen;
1090 					if (*endnum > (i + 1))
1091 						memmove(&laarr[i],
1092 							&laarr[i + 1],
1093 							sizeof(struct long_ad) *
1094 							(*endnum - (i + 1)));
1095 					i--;
1096 					(*endnum)--;
1097 				}
1098 			}
1099 			UDF_I(inode)->i_lenExtents +=
1100 				numalloc << inode->i_sb->s_blocksize_bits;
1101 		}
1102 	}
1103 }
1104 
1105 static void udf_merge_extents(struct inode *inode, struct kernel_long_ad *laarr,
1106 			      int *endnum)
1107 {
1108 	int i;
1109 	unsigned long blocksize = inode->i_sb->s_blocksize;
1110 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1111 
1112 	for (i = 0; i < (*endnum - 1); i++) {
1113 		struct kernel_long_ad *li /*l[i]*/ = &laarr[i];
1114 		struct kernel_long_ad *lip1 /*l[i plus 1]*/ = &laarr[i + 1];
1115 
1116 		if (((li->extLength >> 30) == (lip1->extLength >> 30)) &&
1117 			(((li->extLength >> 30) ==
1118 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) ||
1119 			((lip1->extLocation.logicalBlockNum -
1120 			  li->extLocation.logicalBlockNum) ==
1121 			(((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1122 			blocksize - 1) >> blocksize_bits)))) {
1123 
1124 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1125 			     (lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1126 			     blocksize - 1) <= UDF_EXTENT_LENGTH_MASK) {
1127 				li->extLength = lip1->extLength +
1128 					(((li->extLength &
1129 						UDF_EXTENT_LENGTH_MASK) +
1130 					 blocksize - 1) & ~(blocksize - 1));
1131 				if (*endnum > (i + 2))
1132 					memmove(&laarr[i + 1], &laarr[i + 2],
1133 						sizeof(struct long_ad) *
1134 						(*endnum - (i + 2)));
1135 				i--;
1136 				(*endnum)--;
1137 			}
1138 		} else if (((li->extLength >> 30) ==
1139 				(EXT_NOT_RECORDED_ALLOCATED >> 30)) &&
1140 			   ((lip1->extLength >> 30) ==
1141 				(EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))) {
1142 			udf_free_blocks(inode->i_sb, inode, &li->extLocation, 0,
1143 					((li->extLength &
1144 					  UDF_EXTENT_LENGTH_MASK) +
1145 					 blocksize - 1) >> blocksize_bits);
1146 			li->extLocation.logicalBlockNum = 0;
1147 			li->extLocation.partitionReferenceNum = 0;
1148 
1149 			if (((li->extLength & UDF_EXTENT_LENGTH_MASK) +
1150 			     (lip1->extLength & UDF_EXTENT_LENGTH_MASK) +
1151 			     blocksize - 1) & ~UDF_EXTENT_LENGTH_MASK) {
1152 				lip1->extLength = (lip1->extLength -
1153 						   (li->extLength &
1154 						   UDF_EXTENT_LENGTH_MASK) +
1155 						   UDF_EXTENT_LENGTH_MASK) &
1156 						   ~(blocksize - 1);
1157 				li->extLength = (li->extLength &
1158 						 UDF_EXTENT_FLAG_MASK) +
1159 						(UDF_EXTENT_LENGTH_MASK + 1) -
1160 						blocksize;
1161 			} else {
1162 				li->extLength = lip1->extLength +
1163 					(((li->extLength &
1164 						UDF_EXTENT_LENGTH_MASK) +
1165 					  blocksize - 1) & ~(blocksize - 1));
1166 				if (*endnum > (i + 2))
1167 					memmove(&laarr[i + 1], &laarr[i + 2],
1168 						sizeof(struct long_ad) *
1169 						(*endnum - (i + 2)));
1170 				i--;
1171 				(*endnum)--;
1172 			}
1173 		} else if ((li->extLength >> 30) ==
1174 					(EXT_NOT_RECORDED_ALLOCATED >> 30)) {
1175 			udf_free_blocks(inode->i_sb, inode,
1176 					&li->extLocation, 0,
1177 					((li->extLength &
1178 						UDF_EXTENT_LENGTH_MASK) +
1179 					 blocksize - 1) >> blocksize_bits);
1180 			li->extLocation.logicalBlockNum = 0;
1181 			li->extLocation.partitionReferenceNum = 0;
1182 			li->extLength = (li->extLength &
1183 						UDF_EXTENT_LENGTH_MASK) |
1184 						EXT_NOT_RECORDED_NOT_ALLOCATED;
1185 		}
1186 	}
1187 }
1188 
1189 static int udf_update_extents(struct inode *inode, struct kernel_long_ad *laarr,
1190 			      int startnum, int endnum,
1191 			      struct extent_position *epos)
1192 {
1193 	int start = 0, i;
1194 	struct kernel_lb_addr tmploc;
1195 	uint32_t tmplen;
1196 	int8_t tmpetype;
1197 	int err;
1198 
1199 	if (startnum > endnum) {
1200 		for (i = 0; i < (startnum - endnum); i++)
1201 			udf_delete_aext(inode, *epos);
1202 	} else if (startnum < endnum) {
1203 		for (i = 0; i < (endnum - startnum); i++) {
1204 			err = udf_insert_aext(inode, *epos,
1205 					      laarr[i].extLocation,
1206 					      laarr[i].extLength);
1207 			/*
1208 			 * If we fail here, we are likely corrupting the extent
1209 			 * list and leaking blocks. At least stop early to
1210 			 * limit the damage.
1211 			 */
1212 			if (err < 0)
1213 				return err;
1214 			err = udf_next_aext(inode, epos, &laarr[i].extLocation,
1215 				      &laarr[i].extLength, &tmpetype, 1);
1216 			if (err < 0)
1217 				return err;
1218 			start++;
1219 		}
1220 	}
1221 
1222 	for (i = start; i < endnum; i++) {
1223 		err = udf_next_aext(inode, epos, &tmploc, &tmplen, &tmpetype, 0);
1224 		if (err < 0)
1225 			return err;
1226 
1227 		udf_write_aext(inode, epos, &laarr[i].extLocation,
1228 			       laarr[i].extLength, 1);
1229 	}
1230 	return 0;
1231 }
1232 
1233 struct buffer_head *udf_bread(struct inode *inode, udf_pblk_t block,
1234 			      int create, int *err)
1235 {
1236 	struct buffer_head *bh = NULL;
1237 	struct udf_map_rq map = {
1238 		.lblk = block,
1239 		.iflags = UDF_MAP_NOPREALLOC | (create ? UDF_MAP_CREATE : 0),
1240 	};
1241 
1242 	*err = udf_map_block(inode, &map);
1243 	if (*err || !(map.oflags & UDF_BLK_MAPPED))
1244 		return NULL;
1245 
1246 	bh = sb_getblk(inode->i_sb, map.pblk);
1247 	if (!bh) {
1248 		*err = -ENOMEM;
1249 		return NULL;
1250 	}
1251 	if (map.oflags & UDF_BLK_NEW) {
1252 		lock_buffer(bh);
1253 		memset(bh->b_data, 0x00, inode->i_sb->s_blocksize);
1254 		set_buffer_uptodate(bh);
1255 		unlock_buffer(bh);
1256 		mark_buffer_dirty_inode(bh, inode);
1257 		return bh;
1258 	}
1259 
1260 	if (bh_read(bh, 0) >= 0)
1261 		return bh;
1262 
1263 	brelse(bh);
1264 	*err = -EIO;
1265 	return NULL;
1266 }
1267 
1268 int udf_setsize(struct inode *inode, loff_t newsize)
1269 {
1270 	int err = 0;
1271 	struct udf_inode_info *iinfo;
1272 	unsigned int bsize = i_blocksize(inode);
1273 
1274 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1275 	      S_ISLNK(inode->i_mode)))
1276 		return -EINVAL;
1277 
1278 	iinfo = UDF_I(inode);
1279 	if (newsize > inode->i_size) {
1280 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1281 			if (bsize >=
1282 			    (udf_file_entry_alloc_offset(inode) + newsize)) {
1283 				down_write(&iinfo->i_data_sem);
1284 				iinfo->i_lenAlloc = newsize;
1285 				up_write(&iinfo->i_data_sem);
1286 				goto set_size;
1287 			}
1288 			err = udf_expand_file_adinicb(inode);
1289 			if (err)
1290 				return err;
1291 		}
1292 		err = udf_extend_file(inode, newsize);
1293 		if (err)
1294 			return err;
1295 set_size:
1296 		truncate_setsize(inode, newsize);
1297 	} else {
1298 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1299 			down_write(&iinfo->i_data_sem);
1300 			udf_clear_extent_cache(inode);
1301 			memset(iinfo->i_data + iinfo->i_lenEAttr + newsize,
1302 			       0x00, bsize - newsize -
1303 			       udf_file_entry_alloc_offset(inode));
1304 			iinfo->i_lenAlloc = newsize;
1305 			truncate_setsize(inode, newsize);
1306 			up_write(&iinfo->i_data_sem);
1307 			goto update_time;
1308 		}
1309 		err = block_truncate_page(inode->i_mapping, newsize,
1310 					  udf_get_block);
1311 		if (err)
1312 			return err;
1313 		truncate_setsize(inode, newsize);
1314 		down_write(&iinfo->i_data_sem);
1315 		udf_clear_extent_cache(inode);
1316 		err = udf_truncate_extents(inode);
1317 		up_write(&iinfo->i_data_sem);
1318 		if (err)
1319 			return err;
1320 	}
1321 update_time:
1322 	inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
1323 	if (IS_SYNC(inode))
1324 		udf_sync_inode(inode);
1325 	else
1326 		mark_inode_dirty(inode);
1327 	return err;
1328 }
1329 
1330 /*
1331  * Maximum length of linked list formed by ICB hierarchy. The chosen number is
1332  * arbitrary - just that we hopefully don't limit any real use of rewritten
1333  * inode on write-once media but avoid looping for too long on corrupted media.
1334  */
1335 #define UDF_MAX_ICB_NESTING 1024
1336 
1337 static int udf_read_inode(struct inode *inode, bool hidden_inode)
1338 {
1339 	struct buffer_head *bh = NULL;
1340 	struct fileEntry *fe;
1341 	struct extendedFileEntry *efe;
1342 	uint16_t ident;
1343 	struct udf_inode_info *iinfo = UDF_I(inode);
1344 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1345 	struct kernel_lb_addr *iloc = &iinfo->i_location;
1346 	unsigned int link_count;
1347 	unsigned int indirections = 0;
1348 	int bs = inode->i_sb->s_blocksize;
1349 	int ret = -EIO;
1350 	uint32_t uid, gid;
1351 	struct timespec64 ts;
1352 
1353 reread:
1354 	if (iloc->partitionReferenceNum >= sbi->s_partitions) {
1355 		udf_debug("partition reference: %u > logical volume partitions: %u\n",
1356 			  iloc->partitionReferenceNum, sbi->s_partitions);
1357 		return -EIO;
1358 	}
1359 
1360 	if (iloc->logicalBlockNum >=
1361 	    sbi->s_partmaps[iloc->partitionReferenceNum].s_partition_len) {
1362 		udf_debug("block=%u, partition=%u out of range\n",
1363 			  iloc->logicalBlockNum, iloc->partitionReferenceNum);
1364 		return -EIO;
1365 	}
1366 
1367 	/*
1368 	 * Set defaults, but the inode is still incomplete!
1369 	 * Note: get_new_inode() sets the following on a new inode:
1370 	 *      i_sb = sb
1371 	 *      i_no = ino
1372 	 *      i_flags = sb->s_flags
1373 	 *      i_state = 0
1374 	 * clean_inode(): zero fills and sets
1375 	 *      i_count = 1
1376 	 *      i_nlink = 1
1377 	 *      i_op = NULL;
1378 	 */
1379 	bh = udf_read_ptagged(inode->i_sb, iloc, 0, &ident);
1380 	if (!bh) {
1381 		udf_err(inode->i_sb, "(ino %lu) failed !bh\n", inode->i_ino);
1382 		return -EIO;
1383 	}
1384 
1385 	if (ident != TAG_IDENT_FE && ident != TAG_IDENT_EFE &&
1386 	    ident != TAG_IDENT_USE) {
1387 		udf_err(inode->i_sb, "(ino %lu) failed ident=%u\n",
1388 			inode->i_ino, ident);
1389 		goto out;
1390 	}
1391 
1392 	fe = (struct fileEntry *)bh->b_data;
1393 	efe = (struct extendedFileEntry *)bh->b_data;
1394 
1395 	if (fe->icbTag.strategyType == cpu_to_le16(4096)) {
1396 		struct buffer_head *ibh;
1397 
1398 		ibh = udf_read_ptagged(inode->i_sb, iloc, 1, &ident);
1399 		if (ident == TAG_IDENT_IE && ibh) {
1400 			struct kernel_lb_addr loc;
1401 			struct indirectEntry *ie;
1402 
1403 			ie = (struct indirectEntry *)ibh->b_data;
1404 			loc = lelb_to_cpu(ie->indirectICB.extLocation);
1405 
1406 			if (ie->indirectICB.extLength) {
1407 				brelse(ibh);
1408 				memcpy(&iinfo->i_location, &loc,
1409 				       sizeof(struct kernel_lb_addr));
1410 				if (++indirections > UDF_MAX_ICB_NESTING) {
1411 					udf_err(inode->i_sb,
1412 						"too many ICBs in ICB hierarchy"
1413 						" (max %d supported)\n",
1414 						UDF_MAX_ICB_NESTING);
1415 					goto out;
1416 				}
1417 				brelse(bh);
1418 				goto reread;
1419 			}
1420 		}
1421 		brelse(ibh);
1422 	} else if (fe->icbTag.strategyType != cpu_to_le16(4)) {
1423 		udf_err(inode->i_sb, "unsupported strategy type: %u\n",
1424 			le16_to_cpu(fe->icbTag.strategyType));
1425 		goto out;
1426 	}
1427 	if (fe->icbTag.strategyType == cpu_to_le16(4))
1428 		iinfo->i_strat4096 = 0;
1429 	else /* if (fe->icbTag.strategyType == cpu_to_le16(4096)) */
1430 		iinfo->i_strat4096 = 1;
1431 
1432 	iinfo->i_alloc_type = le16_to_cpu(fe->icbTag.flags) &
1433 							ICBTAG_FLAG_AD_MASK;
1434 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_SHORT &&
1435 	    iinfo->i_alloc_type != ICBTAG_FLAG_AD_LONG &&
1436 	    iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
1437 		ret = -EIO;
1438 		goto out;
1439 	}
1440 	iinfo->i_hidden = hidden_inode;
1441 	iinfo->i_unique = 0;
1442 	iinfo->i_lenEAttr = 0;
1443 	iinfo->i_lenExtents = 0;
1444 	iinfo->i_lenAlloc = 0;
1445 	iinfo->i_next_alloc_block = 0;
1446 	iinfo->i_next_alloc_goal = 0;
1447 	if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_EFE)) {
1448 		iinfo->i_efe = 1;
1449 		iinfo->i_use = 0;
1450 		ret = udf_alloc_i_data(inode, bs -
1451 					sizeof(struct extendedFileEntry));
1452 		if (ret)
1453 			goto out;
1454 		memcpy(iinfo->i_data,
1455 		       bh->b_data + sizeof(struct extendedFileEntry),
1456 		       bs - sizeof(struct extendedFileEntry));
1457 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_FE)) {
1458 		iinfo->i_efe = 0;
1459 		iinfo->i_use = 0;
1460 		ret = udf_alloc_i_data(inode, bs - sizeof(struct fileEntry));
1461 		if (ret)
1462 			goto out;
1463 		memcpy(iinfo->i_data,
1464 		       bh->b_data + sizeof(struct fileEntry),
1465 		       bs - sizeof(struct fileEntry));
1466 	} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_USE)) {
1467 		iinfo->i_efe = 0;
1468 		iinfo->i_use = 1;
1469 		iinfo->i_lenAlloc = le32_to_cpu(
1470 				((struct unallocSpaceEntry *)bh->b_data)->
1471 				 lengthAllocDescs);
1472 		ret = udf_alloc_i_data(inode, bs -
1473 					sizeof(struct unallocSpaceEntry));
1474 		if (ret)
1475 			goto out;
1476 		memcpy(iinfo->i_data,
1477 		       bh->b_data + sizeof(struct unallocSpaceEntry),
1478 		       bs - sizeof(struct unallocSpaceEntry));
1479 		return 0;
1480 	}
1481 
1482 	ret = -EIO;
1483 	read_lock(&sbi->s_cred_lock);
1484 	uid = le32_to_cpu(fe->uid);
1485 	if (uid == UDF_INVALID_ID ||
1486 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_SET))
1487 		inode->i_uid = sbi->s_uid;
1488 	else
1489 		i_uid_write(inode, uid);
1490 
1491 	gid = le32_to_cpu(fe->gid);
1492 	if (gid == UDF_INVALID_ID ||
1493 	    UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_SET))
1494 		inode->i_gid = sbi->s_gid;
1495 	else
1496 		i_gid_write(inode, gid);
1497 
1498 	if (fe->icbTag.fileType != ICBTAG_FILE_TYPE_DIRECTORY &&
1499 			sbi->s_fmode != UDF_INVALID_MODE)
1500 		inode->i_mode = sbi->s_fmode;
1501 	else if (fe->icbTag.fileType == ICBTAG_FILE_TYPE_DIRECTORY &&
1502 			sbi->s_dmode != UDF_INVALID_MODE)
1503 		inode->i_mode = sbi->s_dmode;
1504 	else
1505 		inode->i_mode = udf_convert_permissions(fe);
1506 	inode->i_mode &= ~sbi->s_umask;
1507 	iinfo->i_extraPerms = le32_to_cpu(fe->permissions) & ~FE_MAPPED_PERMS;
1508 
1509 	read_unlock(&sbi->s_cred_lock);
1510 
1511 	link_count = le16_to_cpu(fe->fileLinkCount);
1512 	if (!link_count) {
1513 		if (!hidden_inode) {
1514 			ret = -ESTALE;
1515 			goto out;
1516 		}
1517 		link_count = 1;
1518 	}
1519 	set_nlink(inode, link_count);
1520 
1521 	inode->i_size = le64_to_cpu(fe->informationLength);
1522 	iinfo->i_lenExtents = inode->i_size;
1523 
1524 	if (iinfo->i_efe == 0) {
1525 		inode->i_blocks = le64_to_cpu(fe->logicalBlocksRecorded) <<
1526 			(inode->i_sb->s_blocksize_bits - 9);
1527 
1528 		udf_disk_stamp_to_time(&ts, fe->accessTime);
1529 		inode_set_atime_to_ts(inode, ts);
1530 		udf_disk_stamp_to_time(&ts, fe->modificationTime);
1531 		inode_set_mtime_to_ts(inode, ts);
1532 		udf_disk_stamp_to_time(&ts, fe->attrTime);
1533 		inode_set_ctime_to_ts(inode, ts);
1534 
1535 		iinfo->i_unique = le64_to_cpu(fe->uniqueID);
1536 		iinfo->i_lenEAttr = le32_to_cpu(fe->lengthExtendedAttr);
1537 		iinfo->i_lenAlloc = le32_to_cpu(fe->lengthAllocDescs);
1538 		iinfo->i_checkpoint = le32_to_cpu(fe->checkpoint);
1539 		iinfo->i_streamdir = 0;
1540 		iinfo->i_lenStreams = 0;
1541 	} else {
1542 		inode->i_blocks = le64_to_cpu(efe->logicalBlocksRecorded) <<
1543 		    (inode->i_sb->s_blocksize_bits - 9);
1544 
1545 		udf_disk_stamp_to_time(&ts, efe->accessTime);
1546 		inode_set_atime_to_ts(inode, ts);
1547 		udf_disk_stamp_to_time(&ts, efe->modificationTime);
1548 		inode_set_mtime_to_ts(inode, ts);
1549 		udf_disk_stamp_to_time(&ts, efe->attrTime);
1550 		inode_set_ctime_to_ts(inode, ts);
1551 		udf_disk_stamp_to_time(&iinfo->i_crtime, efe->createTime);
1552 
1553 		iinfo->i_unique = le64_to_cpu(efe->uniqueID);
1554 		iinfo->i_lenEAttr = le32_to_cpu(efe->lengthExtendedAttr);
1555 		iinfo->i_lenAlloc = le32_to_cpu(efe->lengthAllocDescs);
1556 		iinfo->i_checkpoint = le32_to_cpu(efe->checkpoint);
1557 
1558 		/* Named streams */
1559 		iinfo->i_streamdir = (efe->streamDirectoryICB.extLength != 0);
1560 		iinfo->i_locStreamdir =
1561 			lelb_to_cpu(efe->streamDirectoryICB.extLocation);
1562 		iinfo->i_lenStreams = le64_to_cpu(efe->objectSize);
1563 		if (iinfo->i_lenStreams >= inode->i_size)
1564 			iinfo->i_lenStreams -= inode->i_size;
1565 		else
1566 			iinfo->i_lenStreams = 0;
1567 	}
1568 	inode->i_generation = iinfo->i_unique;
1569 
1570 	/*
1571 	 * Sanity check length of allocation descriptors and extended attrs to
1572 	 * avoid integer overflows
1573 	 */
1574 	if (iinfo->i_lenEAttr > bs || iinfo->i_lenAlloc > bs)
1575 		goto out;
1576 	/* Now do exact checks */
1577 	if (udf_file_entry_alloc_offset(inode) + iinfo->i_lenAlloc > bs)
1578 		goto out;
1579 	/* Sanity checks for files in ICB so that we don't get confused later */
1580 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1581 		/*
1582 		 * For file in ICB data is stored in allocation descriptor
1583 		 * so sizes should match
1584 		 */
1585 		if (iinfo->i_lenAlloc != inode->i_size)
1586 			goto out;
1587 		/* File in ICB has to fit in there... */
1588 		if (inode->i_size > bs - udf_file_entry_alloc_offset(inode))
1589 			goto out;
1590 	}
1591 
1592 	switch (fe->icbTag.fileType) {
1593 	case ICBTAG_FILE_TYPE_DIRECTORY:
1594 		inode->i_op = &udf_dir_inode_operations;
1595 		inode->i_fop = &udf_dir_operations;
1596 		inode->i_mode |= S_IFDIR;
1597 		inc_nlink(inode);
1598 		break;
1599 	case ICBTAG_FILE_TYPE_REALTIME:
1600 	case ICBTAG_FILE_TYPE_REGULAR:
1601 	case ICBTAG_FILE_TYPE_UNDEF:
1602 	case ICBTAG_FILE_TYPE_VAT20:
1603 		inode->i_data.a_ops = &udf_aops;
1604 		inode->i_op = &udf_file_inode_operations;
1605 		inode->i_fop = &udf_file_operations;
1606 		inode->i_mode |= S_IFREG;
1607 		break;
1608 	case ICBTAG_FILE_TYPE_BLOCK:
1609 		inode->i_mode |= S_IFBLK;
1610 		break;
1611 	case ICBTAG_FILE_TYPE_CHAR:
1612 		inode->i_mode |= S_IFCHR;
1613 		break;
1614 	case ICBTAG_FILE_TYPE_FIFO:
1615 		init_special_inode(inode, inode->i_mode | S_IFIFO, 0);
1616 		break;
1617 	case ICBTAG_FILE_TYPE_SOCKET:
1618 		init_special_inode(inode, inode->i_mode | S_IFSOCK, 0);
1619 		break;
1620 	case ICBTAG_FILE_TYPE_SYMLINK:
1621 		inode->i_data.a_ops = &udf_symlink_aops;
1622 		inode->i_op = &udf_symlink_inode_operations;
1623 		inode_nohighmem(inode);
1624 		inode->i_mode = S_IFLNK | 0777;
1625 		break;
1626 	case ICBTAG_FILE_TYPE_MAIN:
1627 		udf_debug("METADATA FILE-----\n");
1628 		break;
1629 	case ICBTAG_FILE_TYPE_MIRROR:
1630 		udf_debug("METADATA MIRROR FILE-----\n");
1631 		break;
1632 	case ICBTAG_FILE_TYPE_BITMAP:
1633 		udf_debug("METADATA BITMAP FILE-----\n");
1634 		break;
1635 	default:
1636 		udf_err(inode->i_sb, "(ino %lu) failed unknown file type=%u\n",
1637 			inode->i_ino, fe->icbTag.fileType);
1638 		goto out;
1639 	}
1640 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1641 		struct deviceSpec *dsea =
1642 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1643 		if (dsea) {
1644 			init_special_inode(inode, inode->i_mode,
1645 				MKDEV(le32_to_cpu(dsea->majorDeviceIdent),
1646 				      le32_to_cpu(dsea->minorDeviceIdent)));
1647 			/* Developer ID ??? */
1648 		} else
1649 			goto out;
1650 	}
1651 	ret = 0;
1652 out:
1653 	brelse(bh);
1654 	return ret;
1655 }
1656 
1657 static int udf_alloc_i_data(struct inode *inode, size_t size)
1658 {
1659 	struct udf_inode_info *iinfo = UDF_I(inode);
1660 	iinfo->i_data = kmalloc(size, GFP_KERNEL);
1661 	if (!iinfo->i_data)
1662 		return -ENOMEM;
1663 	return 0;
1664 }
1665 
1666 static umode_t udf_convert_permissions(struct fileEntry *fe)
1667 {
1668 	umode_t mode;
1669 	uint32_t permissions;
1670 	uint32_t flags;
1671 
1672 	permissions = le32_to_cpu(fe->permissions);
1673 	flags = le16_to_cpu(fe->icbTag.flags);
1674 
1675 	mode =	((permissions) & 0007) |
1676 		((permissions >> 2) & 0070) |
1677 		((permissions >> 4) & 0700) |
1678 		((flags & ICBTAG_FLAG_SETUID) ? S_ISUID : 0) |
1679 		((flags & ICBTAG_FLAG_SETGID) ? S_ISGID : 0) |
1680 		((flags & ICBTAG_FLAG_STICKY) ? S_ISVTX : 0);
1681 
1682 	return mode;
1683 }
1684 
1685 void udf_update_extra_perms(struct inode *inode, umode_t mode)
1686 {
1687 	struct udf_inode_info *iinfo = UDF_I(inode);
1688 
1689 	/*
1690 	 * UDF 2.01 sec. 3.3.3.3 Note 2:
1691 	 * In Unix, delete permission tracks write
1692 	 */
1693 	iinfo->i_extraPerms &= ~FE_DELETE_PERMS;
1694 	if (mode & 0200)
1695 		iinfo->i_extraPerms |= FE_PERM_U_DELETE;
1696 	if (mode & 0020)
1697 		iinfo->i_extraPerms |= FE_PERM_G_DELETE;
1698 	if (mode & 0002)
1699 		iinfo->i_extraPerms |= FE_PERM_O_DELETE;
1700 }
1701 
1702 int udf_write_inode(struct inode *inode, struct writeback_control *wbc)
1703 {
1704 	return udf_update_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
1705 }
1706 
1707 static int udf_sync_inode(struct inode *inode)
1708 {
1709 	return udf_update_inode(inode, 1);
1710 }
1711 
1712 static void udf_adjust_time(struct udf_inode_info *iinfo, struct timespec64 time)
1713 {
1714 	if (iinfo->i_crtime.tv_sec > time.tv_sec ||
1715 	    (iinfo->i_crtime.tv_sec == time.tv_sec &&
1716 	     iinfo->i_crtime.tv_nsec > time.tv_nsec))
1717 		iinfo->i_crtime = time;
1718 }
1719 
1720 static int udf_update_inode(struct inode *inode, int do_sync)
1721 {
1722 	struct buffer_head *bh = NULL;
1723 	struct fileEntry *fe;
1724 	struct extendedFileEntry *efe;
1725 	uint64_t lb_recorded;
1726 	uint32_t udfperms;
1727 	uint16_t icbflags;
1728 	uint16_t crclen;
1729 	int err = 0;
1730 	struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
1731 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
1732 	struct udf_inode_info *iinfo = UDF_I(inode);
1733 
1734 	bh = sb_getblk(inode->i_sb,
1735 			udf_get_lb_pblock(inode->i_sb, &iinfo->i_location, 0));
1736 	if (!bh) {
1737 		udf_debug("getblk failure\n");
1738 		return -EIO;
1739 	}
1740 
1741 	lock_buffer(bh);
1742 	memset(bh->b_data, 0, inode->i_sb->s_blocksize);
1743 	fe = (struct fileEntry *)bh->b_data;
1744 	efe = (struct extendedFileEntry *)bh->b_data;
1745 
1746 	if (iinfo->i_use) {
1747 		struct unallocSpaceEntry *use =
1748 			(struct unallocSpaceEntry *)bh->b_data;
1749 
1750 		use->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1751 		memcpy(bh->b_data + sizeof(struct unallocSpaceEntry),
1752 		       iinfo->i_data, inode->i_sb->s_blocksize -
1753 					sizeof(struct unallocSpaceEntry));
1754 		use->descTag.tagIdent = cpu_to_le16(TAG_IDENT_USE);
1755 		crclen = sizeof(struct unallocSpaceEntry);
1756 
1757 		goto finish;
1758 	}
1759 
1760 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_FORGET))
1761 		fe->uid = cpu_to_le32(UDF_INVALID_ID);
1762 	else
1763 		fe->uid = cpu_to_le32(i_uid_read(inode));
1764 
1765 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_FORGET))
1766 		fe->gid = cpu_to_le32(UDF_INVALID_ID);
1767 	else
1768 		fe->gid = cpu_to_le32(i_gid_read(inode));
1769 
1770 	udfperms = ((inode->i_mode & 0007)) |
1771 		   ((inode->i_mode & 0070) << 2) |
1772 		   ((inode->i_mode & 0700) << 4);
1773 
1774 	udfperms |= iinfo->i_extraPerms;
1775 	fe->permissions = cpu_to_le32(udfperms);
1776 
1777 	if (S_ISDIR(inode->i_mode) && inode->i_nlink > 0)
1778 		fe->fileLinkCount = cpu_to_le16(inode->i_nlink - 1);
1779 	else {
1780 		if (iinfo->i_hidden)
1781 			fe->fileLinkCount = cpu_to_le16(0);
1782 		else
1783 			fe->fileLinkCount = cpu_to_le16(inode->i_nlink);
1784 	}
1785 
1786 	fe->informationLength = cpu_to_le64(inode->i_size);
1787 
1788 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1789 		struct regid *eid;
1790 		struct deviceSpec *dsea =
1791 			(struct deviceSpec *)udf_get_extendedattr(inode, 12, 1);
1792 		if (!dsea) {
1793 			dsea = (struct deviceSpec *)
1794 				udf_add_extendedattr(inode,
1795 						     sizeof(struct deviceSpec) +
1796 						     sizeof(struct regid), 12, 0x3);
1797 			dsea->attrType = cpu_to_le32(12);
1798 			dsea->attrSubtype = 1;
1799 			dsea->attrLength = cpu_to_le32(
1800 						sizeof(struct deviceSpec) +
1801 						sizeof(struct regid));
1802 			dsea->impUseLength = cpu_to_le32(sizeof(struct regid));
1803 		}
1804 		eid = (struct regid *)dsea->impUse;
1805 		memset(eid, 0, sizeof(*eid));
1806 		strcpy(eid->ident, UDF_ID_DEVELOPER);
1807 		eid->identSuffix[0] = UDF_OS_CLASS_UNIX;
1808 		eid->identSuffix[1] = UDF_OS_ID_LINUX;
1809 		dsea->majorDeviceIdent = cpu_to_le32(imajor(inode));
1810 		dsea->minorDeviceIdent = cpu_to_le32(iminor(inode));
1811 	}
1812 
1813 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1814 		lb_recorded = 0; /* No extents => no blocks! */
1815 	else
1816 		lb_recorded =
1817 			(inode->i_blocks + (1 << (blocksize_bits - 9)) - 1) >>
1818 			(blocksize_bits - 9);
1819 
1820 	if (iinfo->i_efe == 0) {
1821 		memcpy(bh->b_data + sizeof(struct fileEntry),
1822 		       iinfo->i_data,
1823 		       inode->i_sb->s_blocksize - sizeof(struct fileEntry));
1824 		fe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
1825 
1826 		udf_time_to_disk_stamp(&fe->accessTime, inode_get_atime(inode));
1827 		udf_time_to_disk_stamp(&fe->modificationTime, inode_get_mtime(inode));
1828 		udf_time_to_disk_stamp(&fe->attrTime, inode_get_ctime(inode));
1829 		memset(&(fe->impIdent), 0, sizeof(struct regid));
1830 		strcpy(fe->impIdent.ident, UDF_ID_DEVELOPER);
1831 		fe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1832 		fe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1833 		fe->uniqueID = cpu_to_le64(iinfo->i_unique);
1834 		fe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
1835 		fe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1836 		fe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
1837 		fe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_FE);
1838 		crclen = sizeof(struct fileEntry);
1839 	} else {
1840 		memcpy(bh->b_data + sizeof(struct extendedFileEntry),
1841 		       iinfo->i_data,
1842 		       inode->i_sb->s_blocksize -
1843 					sizeof(struct extendedFileEntry));
1844 		efe->objectSize =
1845 			cpu_to_le64(inode->i_size + iinfo->i_lenStreams);
1846 		efe->logicalBlocksRecorded = cpu_to_le64(lb_recorded);
1847 
1848 		if (iinfo->i_streamdir) {
1849 			struct long_ad *icb_lad = &efe->streamDirectoryICB;
1850 
1851 			icb_lad->extLocation =
1852 				cpu_to_lelb(iinfo->i_locStreamdir);
1853 			icb_lad->extLength =
1854 				cpu_to_le32(inode->i_sb->s_blocksize);
1855 		}
1856 
1857 		udf_adjust_time(iinfo, inode_get_atime(inode));
1858 		udf_adjust_time(iinfo, inode_get_mtime(inode));
1859 		udf_adjust_time(iinfo, inode_get_ctime(inode));
1860 
1861 		udf_time_to_disk_stamp(&efe->accessTime,
1862 				       inode_get_atime(inode));
1863 		udf_time_to_disk_stamp(&efe->modificationTime,
1864 				       inode_get_mtime(inode));
1865 		udf_time_to_disk_stamp(&efe->createTime, iinfo->i_crtime);
1866 		udf_time_to_disk_stamp(&efe->attrTime, inode_get_ctime(inode));
1867 
1868 		memset(&(efe->impIdent), 0, sizeof(efe->impIdent));
1869 		strcpy(efe->impIdent.ident, UDF_ID_DEVELOPER);
1870 		efe->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1871 		efe->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1872 		efe->uniqueID = cpu_to_le64(iinfo->i_unique);
1873 		efe->lengthExtendedAttr = cpu_to_le32(iinfo->i_lenEAttr);
1874 		efe->lengthAllocDescs = cpu_to_le32(iinfo->i_lenAlloc);
1875 		efe->checkpoint = cpu_to_le32(iinfo->i_checkpoint);
1876 		efe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EFE);
1877 		crclen = sizeof(struct extendedFileEntry);
1878 	}
1879 
1880 finish:
1881 	if (iinfo->i_strat4096) {
1882 		fe->icbTag.strategyType = cpu_to_le16(4096);
1883 		fe->icbTag.strategyParameter = cpu_to_le16(1);
1884 		fe->icbTag.numEntries = cpu_to_le16(2);
1885 	} else {
1886 		fe->icbTag.strategyType = cpu_to_le16(4);
1887 		fe->icbTag.numEntries = cpu_to_le16(1);
1888 	}
1889 
1890 	if (iinfo->i_use)
1891 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_USE;
1892 	else if (S_ISDIR(inode->i_mode))
1893 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_DIRECTORY;
1894 	else if (S_ISREG(inode->i_mode))
1895 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_REGULAR;
1896 	else if (S_ISLNK(inode->i_mode))
1897 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SYMLINK;
1898 	else if (S_ISBLK(inode->i_mode))
1899 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_BLOCK;
1900 	else if (S_ISCHR(inode->i_mode))
1901 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_CHAR;
1902 	else if (S_ISFIFO(inode->i_mode))
1903 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_FIFO;
1904 	else if (S_ISSOCK(inode->i_mode))
1905 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_SOCKET;
1906 
1907 	icbflags =	iinfo->i_alloc_type |
1908 			((inode->i_mode & S_ISUID) ? ICBTAG_FLAG_SETUID : 0) |
1909 			((inode->i_mode & S_ISGID) ? ICBTAG_FLAG_SETGID : 0) |
1910 			((inode->i_mode & S_ISVTX) ? ICBTAG_FLAG_STICKY : 0) |
1911 			(le16_to_cpu(fe->icbTag.flags) &
1912 				~(ICBTAG_FLAG_AD_MASK | ICBTAG_FLAG_SETUID |
1913 				ICBTAG_FLAG_SETGID | ICBTAG_FLAG_STICKY));
1914 
1915 	fe->icbTag.flags = cpu_to_le16(icbflags);
1916 	if (sbi->s_udfrev >= 0x0200)
1917 		fe->descTag.descVersion = cpu_to_le16(3);
1918 	else
1919 		fe->descTag.descVersion = cpu_to_le16(2);
1920 	fe->descTag.tagSerialNum = cpu_to_le16(sbi->s_serial_number);
1921 	fe->descTag.tagLocation = cpu_to_le32(
1922 					iinfo->i_location.logicalBlockNum);
1923 	crclen += iinfo->i_lenEAttr + iinfo->i_lenAlloc - sizeof(struct tag);
1924 	fe->descTag.descCRCLength = cpu_to_le16(crclen);
1925 	fe->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)fe + sizeof(struct tag),
1926 						  crclen));
1927 	fe->descTag.tagChecksum = udf_tag_checksum(&fe->descTag);
1928 
1929 	set_buffer_uptodate(bh);
1930 	unlock_buffer(bh);
1931 
1932 	/* write the data blocks */
1933 	mark_buffer_dirty(bh);
1934 	if (do_sync) {
1935 		sync_dirty_buffer(bh);
1936 		if (buffer_write_io_error(bh)) {
1937 			udf_warn(inode->i_sb, "IO error syncing udf inode [%08lx]\n",
1938 				 inode->i_ino);
1939 			err = -EIO;
1940 		}
1941 	}
1942 	brelse(bh);
1943 
1944 	return err;
1945 }
1946 
1947 struct inode *__udf_iget(struct super_block *sb, struct kernel_lb_addr *ino,
1948 			 bool hidden_inode)
1949 {
1950 	unsigned long block = udf_get_lb_pblock(sb, ino, 0);
1951 	struct inode *inode = iget_locked(sb, block);
1952 	int err;
1953 
1954 	if (!inode)
1955 		return ERR_PTR(-ENOMEM);
1956 
1957 	if (!(inode->i_state & I_NEW)) {
1958 		if (UDF_I(inode)->i_hidden != hidden_inode) {
1959 			iput(inode);
1960 			return ERR_PTR(-EFSCORRUPTED);
1961 		}
1962 		return inode;
1963 	}
1964 
1965 	memcpy(&UDF_I(inode)->i_location, ino, sizeof(struct kernel_lb_addr));
1966 	err = udf_read_inode(inode, hidden_inode);
1967 	if (err < 0) {
1968 		iget_failed(inode);
1969 		return ERR_PTR(err);
1970 	}
1971 	unlock_new_inode(inode);
1972 
1973 	return inode;
1974 }
1975 
1976 int udf_setup_indirect_aext(struct inode *inode, udf_pblk_t block,
1977 			    struct extent_position *epos)
1978 {
1979 	struct super_block *sb = inode->i_sb;
1980 	struct buffer_head *bh;
1981 	struct allocExtDesc *aed;
1982 	struct extent_position nepos;
1983 	struct kernel_lb_addr neloc;
1984 	int ver, adsize;
1985 	int err = 0;
1986 
1987 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
1988 		adsize = sizeof(struct short_ad);
1989 	else if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_LONG)
1990 		adsize = sizeof(struct long_ad);
1991 	else
1992 		return -EIO;
1993 
1994 	neloc.logicalBlockNum = block;
1995 	neloc.partitionReferenceNum = epos->block.partitionReferenceNum;
1996 
1997 	bh = sb_getblk(sb, udf_get_lb_pblock(sb, &neloc, 0));
1998 	if (!bh)
1999 		return -EIO;
2000 	lock_buffer(bh);
2001 	memset(bh->b_data, 0x00, sb->s_blocksize);
2002 	set_buffer_uptodate(bh);
2003 	unlock_buffer(bh);
2004 	mark_buffer_dirty_inode(bh, inode);
2005 
2006 	aed = (struct allocExtDesc *)(bh->b_data);
2007 	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT)) {
2008 		aed->previousAllocExtLocation =
2009 				cpu_to_le32(epos->block.logicalBlockNum);
2010 	}
2011 	aed->lengthAllocDescs = cpu_to_le32(0);
2012 	if (UDF_SB(sb)->s_udfrev >= 0x0200)
2013 		ver = 3;
2014 	else
2015 		ver = 2;
2016 	udf_new_tag(bh->b_data, TAG_IDENT_AED, ver, 1, block,
2017 		    sizeof(struct tag));
2018 
2019 	nepos.block = neloc;
2020 	nepos.offset = sizeof(struct allocExtDesc);
2021 	nepos.bh = bh;
2022 
2023 	/*
2024 	 * Do we have to copy current last extent to make space for indirect
2025 	 * one?
2026 	 */
2027 	if (epos->offset + adsize > sb->s_blocksize) {
2028 		struct kernel_lb_addr cp_loc;
2029 		uint32_t cp_len;
2030 		int8_t cp_type;
2031 
2032 		epos->offset -= adsize;
2033 		err = udf_current_aext(inode, epos, &cp_loc, &cp_len, &cp_type, 0);
2034 		if (err <= 0)
2035 			goto err_out;
2036 		cp_len |= ((uint32_t)cp_type) << 30;
2037 
2038 		__udf_add_aext(inode, &nepos, &cp_loc, cp_len, 1);
2039 		udf_write_aext(inode, epos, &nepos.block,
2040 			       sb->s_blocksize | EXT_NEXT_EXTENT_ALLOCDESCS, 0);
2041 	} else {
2042 		__udf_add_aext(inode, epos, &nepos.block,
2043 			       sb->s_blocksize | EXT_NEXT_EXTENT_ALLOCDESCS, 0);
2044 	}
2045 
2046 	brelse(epos->bh);
2047 	*epos = nepos;
2048 
2049 	return 0;
2050 err_out:
2051 	brelse(bh);
2052 	return err;
2053 }
2054 
2055 /*
2056  * Append extent at the given position - should be the first free one in inode
2057  * / indirect extent. This function assumes there is enough space in the inode
2058  * or indirect extent. Use udf_add_aext() if you didn't check for this before.
2059  */
2060 int __udf_add_aext(struct inode *inode, struct extent_position *epos,
2061 		   struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2062 {
2063 	struct udf_inode_info *iinfo = UDF_I(inode);
2064 	struct allocExtDesc *aed;
2065 	int adsize;
2066 
2067 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2068 		adsize = sizeof(struct short_ad);
2069 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2070 		adsize = sizeof(struct long_ad);
2071 	else
2072 		return -EIO;
2073 
2074 	if (!epos->bh) {
2075 		WARN_ON(iinfo->i_lenAlloc !=
2076 			epos->offset - udf_file_entry_alloc_offset(inode));
2077 	} else {
2078 		aed = (struct allocExtDesc *)epos->bh->b_data;
2079 		WARN_ON(le32_to_cpu(aed->lengthAllocDescs) !=
2080 			epos->offset - sizeof(struct allocExtDesc));
2081 		WARN_ON(epos->offset + adsize > inode->i_sb->s_blocksize);
2082 	}
2083 
2084 	udf_write_aext(inode, epos, eloc, elen, inc);
2085 
2086 	if (!epos->bh) {
2087 		iinfo->i_lenAlloc += adsize;
2088 		mark_inode_dirty(inode);
2089 	} else {
2090 		aed = (struct allocExtDesc *)epos->bh->b_data;
2091 		le32_add_cpu(&aed->lengthAllocDescs, adsize);
2092 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2093 				UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2094 			udf_update_tag(epos->bh->b_data,
2095 					epos->offset + (inc ? 0 : adsize));
2096 		else
2097 			udf_update_tag(epos->bh->b_data,
2098 					sizeof(struct allocExtDesc));
2099 		mark_buffer_dirty_inode(epos->bh, inode);
2100 	}
2101 
2102 	return 0;
2103 }
2104 
2105 /*
2106  * Append extent at given position - should be the first free one in inode
2107  * / indirect extent. Takes care of allocating and linking indirect blocks.
2108  */
2109 int udf_add_aext(struct inode *inode, struct extent_position *epos,
2110 		 struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2111 {
2112 	int adsize;
2113 	struct super_block *sb = inode->i_sb;
2114 
2115 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2116 		adsize = sizeof(struct short_ad);
2117 	else if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2118 		adsize = sizeof(struct long_ad);
2119 	else
2120 		return -EIO;
2121 
2122 	if (epos->offset + (2 * adsize) > sb->s_blocksize) {
2123 		int err;
2124 		udf_pblk_t new_block;
2125 
2126 		new_block = udf_new_block(sb, NULL,
2127 					  epos->block.partitionReferenceNum,
2128 					  epos->block.logicalBlockNum, &err);
2129 		if (!new_block)
2130 			return -ENOSPC;
2131 
2132 		err = udf_setup_indirect_aext(inode, new_block, epos);
2133 		if (err)
2134 			return err;
2135 	}
2136 
2137 	return __udf_add_aext(inode, epos, eloc, elen, inc);
2138 }
2139 
2140 void udf_write_aext(struct inode *inode, struct extent_position *epos,
2141 		    struct kernel_lb_addr *eloc, uint32_t elen, int inc)
2142 {
2143 	int adsize;
2144 	uint8_t *ptr;
2145 	struct short_ad *sad;
2146 	struct long_ad *lad;
2147 	struct udf_inode_info *iinfo = UDF_I(inode);
2148 
2149 	if (!epos->bh)
2150 		ptr = iinfo->i_data + epos->offset -
2151 			udf_file_entry_alloc_offset(inode) +
2152 			iinfo->i_lenEAttr;
2153 	else
2154 		ptr = epos->bh->b_data + epos->offset;
2155 
2156 	switch (iinfo->i_alloc_type) {
2157 	case ICBTAG_FLAG_AD_SHORT:
2158 		sad = (struct short_ad *)ptr;
2159 		sad->extLength = cpu_to_le32(elen);
2160 		sad->extPosition = cpu_to_le32(eloc->logicalBlockNum);
2161 		adsize = sizeof(struct short_ad);
2162 		break;
2163 	case ICBTAG_FLAG_AD_LONG:
2164 		lad = (struct long_ad *)ptr;
2165 		lad->extLength = cpu_to_le32(elen);
2166 		lad->extLocation = cpu_to_lelb(*eloc);
2167 		memset(lad->impUse, 0x00, sizeof(lad->impUse));
2168 		adsize = sizeof(struct long_ad);
2169 		break;
2170 	default:
2171 		return;
2172 	}
2173 
2174 	if (epos->bh) {
2175 		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2176 		    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201) {
2177 			struct allocExtDesc *aed =
2178 				(struct allocExtDesc *)epos->bh->b_data;
2179 			udf_update_tag(epos->bh->b_data,
2180 				       le32_to_cpu(aed->lengthAllocDescs) +
2181 				       sizeof(struct allocExtDesc));
2182 		}
2183 		mark_buffer_dirty_inode(epos->bh, inode);
2184 	} else {
2185 		mark_inode_dirty(inode);
2186 	}
2187 
2188 	if (inc)
2189 		epos->offset += adsize;
2190 }
2191 
2192 /*
2193  * Only 1 indirect extent in a row really makes sense but allow upto 16 in case
2194  * someone does some weird stuff.
2195  */
2196 #define UDF_MAX_INDIR_EXTS 16
2197 
2198 /*
2199  * Returns 1 on success, -errno on error, 0 on hit EOF.
2200  */
2201 int udf_next_aext(struct inode *inode, struct extent_position *epos,
2202 		  struct kernel_lb_addr *eloc, uint32_t *elen, int8_t *etype,
2203 		  int inc)
2204 {
2205 	unsigned int indirections = 0;
2206 	int ret = 0;
2207 	udf_pblk_t block;
2208 
2209 	while (1) {
2210 		ret = udf_current_aext(inode, epos, eloc, elen,
2211 				       etype, inc);
2212 		if (ret <= 0)
2213 			return ret;
2214 		if (*etype != (EXT_NEXT_EXTENT_ALLOCDESCS >> 30))
2215 			return ret;
2216 
2217 		if (++indirections > UDF_MAX_INDIR_EXTS) {
2218 			udf_err(inode->i_sb,
2219 				"too many indirect extents in inode %lu\n",
2220 				inode->i_ino);
2221 			return -EFSCORRUPTED;
2222 		}
2223 
2224 		epos->block = *eloc;
2225 		epos->offset = sizeof(struct allocExtDesc);
2226 		brelse(epos->bh);
2227 		block = udf_get_lb_pblock(inode->i_sb, &epos->block, 0);
2228 		epos->bh = sb_bread(inode->i_sb, block);
2229 		if (!epos->bh) {
2230 			udf_debug("reading block %u failed!\n", block);
2231 			return -EIO;
2232 		}
2233 	}
2234 }
2235 
2236 /*
2237  * Returns 1 on success, -errno on error, 0 on hit EOF.
2238  */
2239 int udf_current_aext(struct inode *inode, struct extent_position *epos,
2240 		     struct kernel_lb_addr *eloc, uint32_t *elen, int8_t *etype,
2241 		     int inc)
2242 {
2243 	int alen;
2244 	uint8_t *ptr;
2245 	struct short_ad *sad;
2246 	struct long_ad *lad;
2247 	struct udf_inode_info *iinfo = UDF_I(inode);
2248 
2249 	if (!epos->bh) {
2250 		if (!epos->offset)
2251 			epos->offset = udf_file_entry_alloc_offset(inode);
2252 		ptr = iinfo->i_data + epos->offset -
2253 			udf_file_entry_alloc_offset(inode) +
2254 			iinfo->i_lenEAttr;
2255 		alen = udf_file_entry_alloc_offset(inode) +
2256 							iinfo->i_lenAlloc;
2257 	} else {
2258 		struct allocExtDesc *header =
2259 			(struct allocExtDesc *)epos->bh->b_data;
2260 
2261 		if (!epos->offset)
2262 			epos->offset = sizeof(struct allocExtDesc);
2263 		ptr = epos->bh->b_data + epos->offset;
2264 		if (check_add_overflow(sizeof(struct allocExtDesc),
2265 				le32_to_cpu(header->lengthAllocDescs), &alen))
2266 			return -1;
2267 	}
2268 
2269 	switch (iinfo->i_alloc_type) {
2270 	case ICBTAG_FLAG_AD_SHORT:
2271 		sad = udf_get_fileshortad(ptr, alen, &epos->offset, inc);
2272 		if (!sad)
2273 			return 0;
2274 		*etype = le32_to_cpu(sad->extLength) >> 30;
2275 		eloc->logicalBlockNum = le32_to_cpu(sad->extPosition);
2276 		eloc->partitionReferenceNum =
2277 				iinfo->i_location.partitionReferenceNum;
2278 		*elen = le32_to_cpu(sad->extLength) & UDF_EXTENT_LENGTH_MASK;
2279 		break;
2280 	case ICBTAG_FLAG_AD_LONG:
2281 		lad = udf_get_filelongad(ptr, alen, &epos->offset, inc);
2282 		if (!lad)
2283 			return 0;
2284 		*etype = le32_to_cpu(lad->extLength) >> 30;
2285 		*eloc = lelb_to_cpu(lad->extLocation);
2286 		*elen = le32_to_cpu(lad->extLength) & UDF_EXTENT_LENGTH_MASK;
2287 		break;
2288 	default:
2289 		udf_debug("alloc_type = %u unsupported\n", iinfo->i_alloc_type);
2290 		return -EINVAL;
2291 	}
2292 
2293 	return 1;
2294 }
2295 
2296 static int udf_insert_aext(struct inode *inode, struct extent_position epos,
2297 			   struct kernel_lb_addr neloc, uint32_t nelen)
2298 {
2299 	struct kernel_lb_addr oeloc;
2300 	uint32_t oelen;
2301 	int8_t etype;
2302 	int ret;
2303 
2304 	if (epos.bh)
2305 		get_bh(epos.bh);
2306 
2307 	while (1) {
2308 		ret = udf_next_aext(inode, &epos, &oeloc, &oelen, &etype, 0);
2309 		if (ret <= 0)
2310 			break;
2311 		udf_write_aext(inode, &epos, &neloc, nelen, 1);
2312 		neloc = oeloc;
2313 		nelen = (etype << 30) | oelen;
2314 	}
2315 	if (ret == 0)
2316 		ret = udf_add_aext(inode, &epos, &neloc, nelen, 1);
2317 	brelse(epos.bh);
2318 
2319 	return ret;
2320 }
2321 
2322 int8_t udf_delete_aext(struct inode *inode, struct extent_position epos)
2323 {
2324 	struct extent_position oepos;
2325 	int adsize;
2326 	int8_t etype;
2327 	struct allocExtDesc *aed;
2328 	struct udf_inode_info *iinfo;
2329 	struct kernel_lb_addr eloc;
2330 	uint32_t elen;
2331 	int ret;
2332 
2333 	if (epos.bh) {
2334 		get_bh(epos.bh);
2335 		get_bh(epos.bh);
2336 	}
2337 
2338 	iinfo = UDF_I(inode);
2339 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
2340 		adsize = sizeof(struct short_ad);
2341 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
2342 		adsize = sizeof(struct long_ad);
2343 	else
2344 		adsize = 0;
2345 
2346 	oepos = epos;
2347 	if (udf_next_aext(inode, &epos, &eloc, &elen, &etype, 1) <= 0)
2348 		return -1;
2349 
2350 	while (1) {
2351 		ret = udf_next_aext(inode, &epos, &eloc, &elen, &etype, 1);
2352 		if (ret < 0) {
2353 			brelse(epos.bh);
2354 			brelse(oepos.bh);
2355 			return -1;
2356 		}
2357 		if (ret == 0)
2358 			break;
2359 		udf_write_aext(inode, &oepos, &eloc, (etype << 30) | elen, 1);
2360 		if (oepos.bh != epos.bh) {
2361 			oepos.block = epos.block;
2362 			brelse(oepos.bh);
2363 			get_bh(epos.bh);
2364 			oepos.bh = epos.bh;
2365 			oepos.offset = epos.offset - adsize;
2366 		}
2367 	}
2368 	memset(&eloc, 0x00, sizeof(struct kernel_lb_addr));
2369 	elen = 0;
2370 
2371 	if (epos.bh != oepos.bh) {
2372 		udf_free_blocks(inode->i_sb, inode, &epos.block, 0, 1);
2373 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2374 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2375 		if (!oepos.bh) {
2376 			iinfo->i_lenAlloc -= (adsize * 2);
2377 			mark_inode_dirty(inode);
2378 		} else {
2379 			aed = (struct allocExtDesc *)oepos.bh->b_data;
2380 			le32_add_cpu(&aed->lengthAllocDescs, -(2 * adsize));
2381 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2382 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2383 				udf_update_tag(oepos.bh->b_data,
2384 						oepos.offset - (2 * adsize));
2385 			else
2386 				udf_update_tag(oepos.bh->b_data,
2387 						sizeof(struct allocExtDesc));
2388 			mark_buffer_dirty_inode(oepos.bh, inode);
2389 		}
2390 	} else {
2391 		udf_write_aext(inode, &oepos, &eloc, elen, 1);
2392 		if (!oepos.bh) {
2393 			iinfo->i_lenAlloc -= adsize;
2394 			mark_inode_dirty(inode);
2395 		} else {
2396 			aed = (struct allocExtDesc *)oepos.bh->b_data;
2397 			le32_add_cpu(&aed->lengthAllocDescs, -adsize);
2398 			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
2399 			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
2400 				udf_update_tag(oepos.bh->b_data,
2401 						epos.offset - adsize);
2402 			else
2403 				udf_update_tag(oepos.bh->b_data,
2404 						sizeof(struct allocExtDesc));
2405 			mark_buffer_dirty_inode(oepos.bh, inode);
2406 		}
2407 	}
2408 
2409 	brelse(epos.bh);
2410 	brelse(oepos.bh);
2411 
2412 	return (elen >> 30);
2413 }
2414 
2415 /*
2416  * Returns 1 on success, -errno on error, 0 on hit EOF.
2417  */
2418 int inode_bmap(struct inode *inode, sector_t block, struct extent_position *pos,
2419 	       struct kernel_lb_addr *eloc, uint32_t *elen, sector_t *offset,
2420 	       int8_t *etype)
2421 {
2422 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
2423 	loff_t lbcount = 0, bcount = (loff_t) block << blocksize_bits;
2424 	struct udf_inode_info *iinfo;
2425 	int err = 0;
2426 
2427 	iinfo = UDF_I(inode);
2428 	if (!udf_read_extent_cache(inode, bcount, &lbcount, pos)) {
2429 		pos->offset = 0;
2430 		pos->block = iinfo->i_location;
2431 		pos->bh = NULL;
2432 	}
2433 	*elen = 0;
2434 	do {
2435 		err = udf_next_aext(inode, pos, eloc, elen, etype, 1);
2436 		if (err <= 0) {
2437 			if (err == 0) {
2438 				*offset = (bcount - lbcount) >> blocksize_bits;
2439 				iinfo->i_lenExtents = lbcount;
2440 			}
2441 			return err;
2442 		}
2443 		lbcount += *elen;
2444 	} while (lbcount <= bcount);
2445 	/* update extent cache */
2446 	udf_update_extent_cache(inode, lbcount - *elen, pos);
2447 	*offset = (bcount + *elen - lbcount) >> blocksize_bits;
2448 
2449 	return 1;
2450 }
2451