xref: /linux/fs/udf/namei.c (revision ebf68996de0ab250c5d520eb2291ab65643e9a1e)
1 /*
2  * namei.c
3  *
4  * PURPOSE
5  *      Inode name handling routines for the OSTA-UDF(tm) filesystem.
6  *
7  * COPYRIGHT
8  *      This file is distributed under the terms of the GNU General Public
9  *      License (GPL). Copies of the GPL can be obtained from:
10  *              ftp://prep.ai.mit.edu/pub/gnu/GPL
11  *      Each contributing author retains all rights to their own work.
12  *
13  *  (C) 1998-2004 Ben Fennema
14  *  (C) 1999-2000 Stelias Computing Inc
15  *
16  * HISTORY
17  *
18  *  12/12/98 blf  Created. Split out the lookup code from dir.c
19  *  04/19/99 blf  link, mknod, symlink support
20  */
21 
22 #include "udfdecl.h"
23 
24 #include "udf_i.h"
25 #include "udf_sb.h"
26 #include <linux/string.h>
27 #include <linux/errno.h>
28 #include <linux/mm.h>
29 #include <linux/slab.h>
30 #include <linux/sched.h>
31 #include <linux/crc-itu-t.h>
32 #include <linux/exportfs.h>
33 
34 static inline int udf_match(int len1, const unsigned char *name1, int len2,
35 			    const unsigned char *name2)
36 {
37 	if (len1 != len2)
38 		return 0;
39 
40 	return !memcmp(name1, name2, len1);
41 }
42 
43 int udf_write_fi(struct inode *inode, struct fileIdentDesc *cfi,
44 		 struct fileIdentDesc *sfi, struct udf_fileident_bh *fibh,
45 		 uint8_t *impuse, uint8_t *fileident)
46 {
47 	uint16_t crclen = fibh->eoffset - fibh->soffset - sizeof(struct tag);
48 	uint16_t crc;
49 	int offset;
50 	uint16_t liu = le16_to_cpu(cfi->lengthOfImpUse);
51 	uint8_t lfi = cfi->lengthFileIdent;
52 	int padlen = fibh->eoffset - fibh->soffset - liu - lfi -
53 		sizeof(struct fileIdentDesc);
54 	int adinicb = 0;
55 
56 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
57 		adinicb = 1;
58 
59 	offset = fibh->soffset + sizeof(struct fileIdentDesc);
60 
61 	if (impuse) {
62 		if (adinicb || (offset + liu < 0)) {
63 			memcpy((uint8_t *)sfi->impUse, impuse, liu);
64 		} else if (offset >= 0) {
65 			memcpy(fibh->ebh->b_data + offset, impuse, liu);
66 		} else {
67 			memcpy((uint8_t *)sfi->impUse, impuse, -offset);
68 			memcpy(fibh->ebh->b_data, impuse - offset,
69 				liu + offset);
70 		}
71 	}
72 
73 	offset += liu;
74 
75 	if (fileident) {
76 		if (adinicb || (offset + lfi < 0)) {
77 			memcpy((uint8_t *)sfi->fileIdent + liu, fileident, lfi);
78 		} else if (offset >= 0) {
79 			memcpy(fibh->ebh->b_data + offset, fileident, lfi);
80 		} else {
81 			memcpy((uint8_t *)sfi->fileIdent + liu, fileident,
82 				-offset);
83 			memcpy(fibh->ebh->b_data, fileident - offset,
84 				lfi + offset);
85 		}
86 	}
87 
88 	offset += lfi;
89 
90 	if (adinicb || (offset + padlen < 0)) {
91 		memset((uint8_t *)sfi->padding + liu + lfi, 0x00, padlen);
92 	} else if (offset >= 0) {
93 		memset(fibh->ebh->b_data + offset, 0x00, padlen);
94 	} else {
95 		memset((uint8_t *)sfi->padding + liu + lfi, 0x00, -offset);
96 		memset(fibh->ebh->b_data, 0x00, padlen + offset);
97 	}
98 
99 	crc = crc_itu_t(0, (uint8_t *)cfi + sizeof(struct tag),
100 		      sizeof(struct fileIdentDesc) - sizeof(struct tag));
101 
102 	if (fibh->sbh == fibh->ebh) {
103 		crc = crc_itu_t(crc, (uint8_t *)sfi->impUse,
104 			      crclen + sizeof(struct tag) -
105 			      sizeof(struct fileIdentDesc));
106 	} else if (sizeof(struct fileIdentDesc) >= -fibh->soffset) {
107 		crc = crc_itu_t(crc, fibh->ebh->b_data +
108 					sizeof(struct fileIdentDesc) +
109 					fibh->soffset,
110 			      crclen + sizeof(struct tag) -
111 					sizeof(struct fileIdentDesc));
112 	} else {
113 		crc = crc_itu_t(crc, (uint8_t *)sfi->impUse,
114 			      -fibh->soffset - sizeof(struct fileIdentDesc));
115 		crc = crc_itu_t(crc, fibh->ebh->b_data, fibh->eoffset);
116 	}
117 
118 	cfi->descTag.descCRC = cpu_to_le16(crc);
119 	cfi->descTag.descCRCLength = cpu_to_le16(crclen);
120 	cfi->descTag.tagChecksum = udf_tag_checksum(&cfi->descTag);
121 
122 	if (adinicb || (sizeof(struct fileIdentDesc) <= -fibh->soffset)) {
123 		memcpy((uint8_t *)sfi, (uint8_t *)cfi,
124 			sizeof(struct fileIdentDesc));
125 	} else {
126 		memcpy((uint8_t *)sfi, (uint8_t *)cfi, -fibh->soffset);
127 		memcpy(fibh->ebh->b_data, (uint8_t *)cfi - fibh->soffset,
128 		       sizeof(struct fileIdentDesc) + fibh->soffset);
129 	}
130 
131 	if (adinicb) {
132 		mark_inode_dirty(inode);
133 	} else {
134 		if (fibh->sbh != fibh->ebh)
135 			mark_buffer_dirty_inode(fibh->ebh, inode);
136 		mark_buffer_dirty_inode(fibh->sbh, inode);
137 	}
138 	return 0;
139 }
140 
141 /**
142  * udf_find_entry - find entry in given directory.
143  *
144  * @dir:	directory inode to search in
145  * @child:	qstr of the name
146  * @fibh:	buffer head / inode with file identifier descriptor we found
147  * @cfi:	found file identifier descriptor with given name
148  *
149  * This function searches in the directory @dir for a file name @child. When
150  * found, @fibh points to the buffer head(s) (bh is NULL for in ICB
151  * directories) containing the file identifier descriptor (FID). In that case
152  * the function returns pointer to the FID in the buffer or inode - but note
153  * that FID may be split among two buffers (blocks) so accessing it via that
154  * pointer isn't easily possible. This pointer can be used only as an iterator
155  * for other directory manipulation functions. For inspection of the FID @cfi
156  * can be used - the found FID is copied there.
157  *
158  * Returns pointer to FID, NULL when nothing found, or error code.
159  */
160 static struct fileIdentDesc *udf_find_entry(struct inode *dir,
161 					    const struct qstr *child,
162 					    struct udf_fileident_bh *fibh,
163 					    struct fileIdentDesc *cfi)
164 {
165 	struct fileIdentDesc *fi = NULL;
166 	loff_t f_pos;
167 	udf_pblk_t block;
168 	int flen;
169 	unsigned char *fname = NULL, *copy_name = NULL;
170 	unsigned char *nameptr;
171 	uint8_t lfi;
172 	uint16_t liu;
173 	loff_t size;
174 	struct kernel_lb_addr eloc;
175 	uint32_t elen;
176 	sector_t offset;
177 	struct extent_position epos = {};
178 	struct udf_inode_info *dinfo = UDF_I(dir);
179 	int isdotdot = child->len == 2 &&
180 		child->name[0] == '.' && child->name[1] == '.';
181 	struct super_block *sb = dir->i_sb;
182 
183 	size = udf_ext0_offset(dir) + dir->i_size;
184 	f_pos = udf_ext0_offset(dir);
185 
186 	fibh->sbh = fibh->ebh = NULL;
187 	fibh->soffset = fibh->eoffset = f_pos & (sb->s_blocksize - 1);
188 	if (dinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
189 		if (inode_bmap(dir, f_pos >> sb->s_blocksize_bits, &epos,
190 		    &eloc, &elen, &offset) != (EXT_RECORDED_ALLOCATED >> 30)) {
191 			fi = ERR_PTR(-EIO);
192 			goto out_err;
193 		}
194 
195 		block = udf_get_lb_pblock(sb, &eloc, offset);
196 		if ((++offset << sb->s_blocksize_bits) < elen) {
197 			if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
198 				epos.offset -= sizeof(struct short_ad);
199 			else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
200 				epos.offset -= sizeof(struct long_ad);
201 		} else
202 			offset = 0;
203 
204 		fibh->sbh = fibh->ebh = udf_tread(sb, block);
205 		if (!fibh->sbh) {
206 			fi = ERR_PTR(-EIO);
207 			goto out_err;
208 		}
209 	}
210 
211 	fname = kmalloc(UDF_NAME_LEN, GFP_NOFS);
212 	if (!fname) {
213 		fi = ERR_PTR(-ENOMEM);
214 		goto out_err;
215 	}
216 
217 	while (f_pos < size) {
218 		fi = udf_fileident_read(dir, &f_pos, fibh, cfi, &epos, &eloc,
219 					&elen, &offset);
220 		if (!fi) {
221 			fi = ERR_PTR(-EIO);
222 			goto out_err;
223 		}
224 
225 		liu = le16_to_cpu(cfi->lengthOfImpUse);
226 		lfi = cfi->lengthFileIdent;
227 
228 		if (fibh->sbh == fibh->ebh) {
229 			nameptr = fi->fileIdent + liu;
230 		} else {
231 			int poffset;	/* Unpaded ending offset */
232 
233 			poffset = fibh->soffset + sizeof(struct fileIdentDesc) +
234 					liu + lfi;
235 
236 			if (poffset >= lfi)
237 				nameptr = (uint8_t *)(fibh->ebh->b_data +
238 						      poffset - lfi);
239 			else {
240 				if (!copy_name) {
241 					copy_name = kmalloc(UDF_NAME_LEN,
242 							    GFP_NOFS);
243 					if (!copy_name) {
244 						fi = ERR_PTR(-ENOMEM);
245 						goto out_err;
246 					}
247 				}
248 				nameptr = copy_name;
249 				memcpy(nameptr, fi->fileIdent + liu,
250 					lfi - poffset);
251 				memcpy(nameptr + lfi - poffset,
252 					fibh->ebh->b_data, poffset);
253 			}
254 		}
255 
256 		if ((cfi->fileCharacteristics & FID_FILE_CHAR_DELETED) != 0) {
257 			if (!UDF_QUERY_FLAG(sb, UDF_FLAG_UNDELETE))
258 				continue;
259 		}
260 
261 		if ((cfi->fileCharacteristics & FID_FILE_CHAR_HIDDEN) != 0) {
262 			if (!UDF_QUERY_FLAG(sb, UDF_FLAG_UNHIDE))
263 				continue;
264 		}
265 
266 		if ((cfi->fileCharacteristics & FID_FILE_CHAR_PARENT) &&
267 		    isdotdot)
268 			goto out_ok;
269 
270 		if (!lfi)
271 			continue;
272 
273 		flen = udf_get_filename(sb, nameptr, lfi, fname, UDF_NAME_LEN);
274 		if (flen < 0) {
275 			fi = ERR_PTR(flen);
276 			goto out_err;
277 		}
278 
279 		if (udf_match(flen, fname, child->len, child->name))
280 			goto out_ok;
281 	}
282 
283 	fi = NULL;
284 out_err:
285 	if (fibh->sbh != fibh->ebh)
286 		brelse(fibh->ebh);
287 	brelse(fibh->sbh);
288 out_ok:
289 	brelse(epos.bh);
290 	kfree(fname);
291 	kfree(copy_name);
292 
293 	return fi;
294 }
295 
296 static struct dentry *udf_lookup(struct inode *dir, struct dentry *dentry,
297 				 unsigned int flags)
298 {
299 	struct inode *inode = NULL;
300 	struct fileIdentDesc cfi;
301 	struct udf_fileident_bh fibh;
302 	struct fileIdentDesc *fi;
303 
304 	if (dentry->d_name.len > UDF_NAME_LEN)
305 		return ERR_PTR(-ENAMETOOLONG);
306 
307 	fi = udf_find_entry(dir, &dentry->d_name, &fibh, &cfi);
308 	if (IS_ERR(fi))
309 		return ERR_CAST(fi);
310 
311 	if (fi) {
312 		struct kernel_lb_addr loc;
313 
314 		if (fibh.sbh != fibh.ebh)
315 			brelse(fibh.ebh);
316 		brelse(fibh.sbh);
317 
318 		loc = lelb_to_cpu(cfi.icb.extLocation);
319 		inode = udf_iget(dir->i_sb, &loc);
320 		if (IS_ERR(inode))
321 			return ERR_CAST(inode);
322 	}
323 
324 	return d_splice_alias(inode, dentry);
325 }
326 
327 static struct fileIdentDesc *udf_add_entry(struct inode *dir,
328 					   struct dentry *dentry,
329 					   struct udf_fileident_bh *fibh,
330 					   struct fileIdentDesc *cfi, int *err)
331 {
332 	struct super_block *sb = dir->i_sb;
333 	struct fileIdentDesc *fi = NULL;
334 	unsigned char *name = NULL;
335 	int namelen;
336 	loff_t f_pos;
337 	loff_t size = udf_ext0_offset(dir) + dir->i_size;
338 	int nfidlen;
339 	udf_pblk_t block;
340 	struct kernel_lb_addr eloc;
341 	uint32_t elen = 0;
342 	sector_t offset;
343 	struct extent_position epos = {};
344 	struct udf_inode_info *dinfo;
345 
346 	fibh->sbh = fibh->ebh = NULL;
347 	name = kmalloc(UDF_NAME_LEN_CS0, GFP_NOFS);
348 	if (!name) {
349 		*err = -ENOMEM;
350 		goto out_err;
351 	}
352 
353 	if (dentry) {
354 		if (!dentry->d_name.len) {
355 			*err = -EINVAL;
356 			goto out_err;
357 		}
358 		namelen = udf_put_filename(sb, dentry->d_name.name,
359 					   dentry->d_name.len,
360 					   name, UDF_NAME_LEN_CS0);
361 		if (!namelen) {
362 			*err = -ENAMETOOLONG;
363 			goto out_err;
364 		}
365 	} else {
366 		namelen = 0;
367 	}
368 
369 	nfidlen = ALIGN(sizeof(struct fileIdentDesc) + namelen, UDF_NAME_PAD);
370 
371 	f_pos = udf_ext0_offset(dir);
372 
373 	fibh->soffset = fibh->eoffset = f_pos & (dir->i_sb->s_blocksize - 1);
374 	dinfo = UDF_I(dir);
375 	if (dinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
376 		if (inode_bmap(dir, f_pos >> dir->i_sb->s_blocksize_bits, &epos,
377 		    &eloc, &elen, &offset) != (EXT_RECORDED_ALLOCATED >> 30)) {
378 			block = udf_get_lb_pblock(dir->i_sb,
379 					&dinfo->i_location, 0);
380 			fibh->soffset = fibh->eoffset = sb->s_blocksize;
381 			goto add;
382 		}
383 		block = udf_get_lb_pblock(dir->i_sb, &eloc, offset);
384 		if ((++offset << dir->i_sb->s_blocksize_bits) < elen) {
385 			if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
386 				epos.offset -= sizeof(struct short_ad);
387 			else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
388 				epos.offset -= sizeof(struct long_ad);
389 		} else
390 			offset = 0;
391 
392 		fibh->sbh = fibh->ebh = udf_tread(dir->i_sb, block);
393 		if (!fibh->sbh) {
394 			*err = -EIO;
395 			goto out_err;
396 		}
397 
398 		block = dinfo->i_location.logicalBlockNum;
399 	}
400 
401 	while (f_pos < size) {
402 		fi = udf_fileident_read(dir, &f_pos, fibh, cfi, &epos, &eloc,
403 					&elen, &offset);
404 
405 		if (!fi) {
406 			*err = -EIO;
407 			goto out_err;
408 		}
409 
410 		if ((cfi->fileCharacteristics & FID_FILE_CHAR_DELETED) != 0) {
411 			if (udf_dir_entry_len(cfi) == nfidlen) {
412 				cfi->descTag.tagSerialNum = cpu_to_le16(1);
413 				cfi->fileVersionNum = cpu_to_le16(1);
414 				cfi->fileCharacteristics = 0;
415 				cfi->lengthFileIdent = namelen;
416 				cfi->lengthOfImpUse = cpu_to_le16(0);
417 				if (!udf_write_fi(dir, cfi, fi, fibh, NULL,
418 						  name))
419 					goto out_ok;
420 				else {
421 					*err = -EIO;
422 					goto out_err;
423 				}
424 			}
425 		}
426 	}
427 
428 add:
429 	f_pos += nfidlen;
430 
431 	if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB &&
432 	    sb->s_blocksize - fibh->eoffset < nfidlen) {
433 		brelse(epos.bh);
434 		epos.bh = NULL;
435 		fibh->soffset -= udf_ext0_offset(dir);
436 		fibh->eoffset -= udf_ext0_offset(dir);
437 		f_pos -= udf_ext0_offset(dir);
438 		if (fibh->sbh != fibh->ebh)
439 			brelse(fibh->ebh);
440 		brelse(fibh->sbh);
441 		fibh->sbh = fibh->ebh =
442 				udf_expand_dir_adinicb(dir, &block, err);
443 		if (!fibh->sbh)
444 			goto out_err;
445 		epos.block = dinfo->i_location;
446 		epos.offset = udf_file_entry_alloc_offset(dir);
447 		/* Load extent udf_expand_dir_adinicb() has created */
448 		udf_current_aext(dir, &epos, &eloc, &elen, 1);
449 	}
450 
451 	/* Entry fits into current block? */
452 	if (sb->s_blocksize - fibh->eoffset >= nfidlen) {
453 		fibh->soffset = fibh->eoffset;
454 		fibh->eoffset += nfidlen;
455 		if (fibh->sbh != fibh->ebh) {
456 			brelse(fibh->sbh);
457 			fibh->sbh = fibh->ebh;
458 		}
459 
460 		if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
461 			block = dinfo->i_location.logicalBlockNum;
462 			fi = (struct fileIdentDesc *)
463 					(dinfo->i_ext.i_data +
464 					 fibh->soffset -
465 					 udf_ext0_offset(dir) +
466 					 dinfo->i_lenEAttr);
467 		} else {
468 			block = eloc.logicalBlockNum +
469 					((elen - 1) >>
470 						dir->i_sb->s_blocksize_bits);
471 			fi = (struct fileIdentDesc *)
472 				(fibh->sbh->b_data + fibh->soffset);
473 		}
474 	} else {
475 		/* Round up last extent in the file */
476 		elen = (elen + sb->s_blocksize - 1) & ~(sb->s_blocksize - 1);
477 		if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
478 			epos.offset -= sizeof(struct short_ad);
479 		else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
480 			epos.offset -= sizeof(struct long_ad);
481 		udf_write_aext(dir, &epos, &eloc, elen, 1);
482 		dinfo->i_lenExtents = (dinfo->i_lenExtents + sb->s_blocksize
483 					- 1) & ~(sb->s_blocksize - 1);
484 
485 		fibh->soffset = fibh->eoffset - sb->s_blocksize;
486 		fibh->eoffset += nfidlen - sb->s_blocksize;
487 		if (fibh->sbh != fibh->ebh) {
488 			brelse(fibh->sbh);
489 			fibh->sbh = fibh->ebh;
490 		}
491 
492 		block = eloc.logicalBlockNum + ((elen - 1) >>
493 						dir->i_sb->s_blocksize_bits);
494 		fibh->ebh = udf_bread(dir,
495 				f_pos >> dir->i_sb->s_blocksize_bits, 1, err);
496 		if (!fibh->ebh)
497 			goto out_err;
498 		/* Extents could have been merged, invalidate our position */
499 		brelse(epos.bh);
500 		epos.bh = NULL;
501 		epos.block = dinfo->i_location;
502 		epos.offset = udf_file_entry_alloc_offset(dir);
503 
504 		if (!fibh->soffset) {
505 			/* Find the freshly allocated block */
506 			while (udf_next_aext(dir, &epos, &eloc, &elen, 1) ==
507 				(EXT_RECORDED_ALLOCATED >> 30))
508 				;
509 			block = eloc.logicalBlockNum + ((elen - 1) >>
510 					dir->i_sb->s_blocksize_bits);
511 			brelse(fibh->sbh);
512 			fibh->sbh = fibh->ebh;
513 			fi = (struct fileIdentDesc *)(fibh->sbh->b_data);
514 		} else {
515 			fi = (struct fileIdentDesc *)
516 				(fibh->sbh->b_data + sb->s_blocksize +
517 					fibh->soffset);
518 		}
519 	}
520 
521 	memset(cfi, 0, sizeof(struct fileIdentDesc));
522 	if (UDF_SB(sb)->s_udfrev >= 0x0200)
523 		udf_new_tag((char *)cfi, TAG_IDENT_FID, 3, 1, block,
524 			    sizeof(struct tag));
525 	else
526 		udf_new_tag((char *)cfi, TAG_IDENT_FID, 2, 1, block,
527 			    sizeof(struct tag));
528 	cfi->fileVersionNum = cpu_to_le16(1);
529 	cfi->lengthFileIdent = namelen;
530 	cfi->lengthOfImpUse = cpu_to_le16(0);
531 	if (!udf_write_fi(dir, cfi, fi, fibh, NULL, name)) {
532 		dir->i_size += nfidlen;
533 		if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
534 			dinfo->i_lenAlloc += nfidlen;
535 		else {
536 			/* Find the last extent and truncate it to proper size */
537 			while (udf_next_aext(dir, &epos, &eloc, &elen, 1) ==
538 				(EXT_RECORDED_ALLOCATED >> 30))
539 				;
540 			elen -= dinfo->i_lenExtents - dir->i_size;
541 			if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
542 				epos.offset -= sizeof(struct short_ad);
543 			else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
544 				epos.offset -= sizeof(struct long_ad);
545 			udf_write_aext(dir, &epos, &eloc, elen, 1);
546 			dinfo->i_lenExtents = dir->i_size;
547 		}
548 
549 		mark_inode_dirty(dir);
550 		goto out_ok;
551 	} else {
552 		*err = -EIO;
553 		goto out_err;
554 	}
555 
556 out_err:
557 	fi = NULL;
558 	if (fibh->sbh != fibh->ebh)
559 		brelse(fibh->ebh);
560 	brelse(fibh->sbh);
561 out_ok:
562 	brelse(epos.bh);
563 	kfree(name);
564 	return fi;
565 }
566 
567 static int udf_delete_entry(struct inode *inode, struct fileIdentDesc *fi,
568 			    struct udf_fileident_bh *fibh,
569 			    struct fileIdentDesc *cfi)
570 {
571 	cfi->fileCharacteristics |= FID_FILE_CHAR_DELETED;
572 
573 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT))
574 		memset(&(cfi->icb), 0x00, sizeof(struct long_ad));
575 
576 	return udf_write_fi(inode, cfi, fi, fibh, NULL, NULL);
577 }
578 
579 static int udf_add_nondir(struct dentry *dentry, struct inode *inode)
580 {
581 	struct udf_inode_info *iinfo = UDF_I(inode);
582 	struct inode *dir = d_inode(dentry->d_parent);
583 	struct udf_fileident_bh fibh;
584 	struct fileIdentDesc cfi, *fi;
585 	int err;
586 
587 	fi = udf_add_entry(dir, dentry, &fibh, &cfi, &err);
588 	if (unlikely(!fi)) {
589 		inode_dec_link_count(inode);
590 		discard_new_inode(inode);
591 		return err;
592 	}
593 	cfi.icb.extLength = cpu_to_le32(inode->i_sb->s_blocksize);
594 	cfi.icb.extLocation = cpu_to_lelb(iinfo->i_location);
595 	*(__le32 *)((struct allocDescImpUse *)cfi.icb.impUse)->impUse =
596 		cpu_to_le32(iinfo->i_unique & 0x00000000FFFFFFFFUL);
597 	udf_write_fi(dir, &cfi, fi, &fibh, NULL, NULL);
598 	dir->i_ctime = dir->i_mtime = current_time(dir);
599 	mark_inode_dirty(dir);
600 	if (fibh.sbh != fibh.ebh)
601 		brelse(fibh.ebh);
602 	brelse(fibh.sbh);
603 	d_instantiate_new(dentry, inode);
604 
605 	return 0;
606 }
607 
608 static int udf_create(struct inode *dir, struct dentry *dentry, umode_t mode,
609 		      bool excl)
610 {
611 	struct inode *inode = udf_new_inode(dir, mode);
612 
613 	if (IS_ERR(inode))
614 		return PTR_ERR(inode);
615 
616 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
617 		inode->i_data.a_ops = &udf_adinicb_aops;
618 	else
619 		inode->i_data.a_ops = &udf_aops;
620 	inode->i_op = &udf_file_inode_operations;
621 	inode->i_fop = &udf_file_operations;
622 	mark_inode_dirty(inode);
623 
624 	return udf_add_nondir(dentry, inode);
625 }
626 
627 static int udf_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
628 {
629 	struct inode *inode = udf_new_inode(dir, mode);
630 
631 	if (IS_ERR(inode))
632 		return PTR_ERR(inode);
633 
634 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
635 		inode->i_data.a_ops = &udf_adinicb_aops;
636 	else
637 		inode->i_data.a_ops = &udf_aops;
638 	inode->i_op = &udf_file_inode_operations;
639 	inode->i_fop = &udf_file_operations;
640 	mark_inode_dirty(inode);
641 	d_tmpfile(dentry, inode);
642 	unlock_new_inode(inode);
643 	return 0;
644 }
645 
646 static int udf_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
647 		     dev_t rdev)
648 {
649 	struct inode *inode;
650 
651 	if (!old_valid_dev(rdev))
652 		return -EINVAL;
653 
654 	inode = udf_new_inode(dir, mode);
655 	if (IS_ERR(inode))
656 		return PTR_ERR(inode);
657 
658 	init_special_inode(inode, mode, rdev);
659 	return udf_add_nondir(dentry, inode);
660 }
661 
662 static int udf_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
663 {
664 	struct inode *inode;
665 	struct udf_fileident_bh fibh;
666 	struct fileIdentDesc cfi, *fi;
667 	int err;
668 	struct udf_inode_info *dinfo = UDF_I(dir);
669 	struct udf_inode_info *iinfo;
670 
671 	inode = udf_new_inode(dir, S_IFDIR | mode);
672 	if (IS_ERR(inode))
673 		return PTR_ERR(inode);
674 
675 	iinfo = UDF_I(inode);
676 	inode->i_op = &udf_dir_inode_operations;
677 	inode->i_fop = &udf_dir_operations;
678 	fi = udf_add_entry(inode, NULL, &fibh, &cfi, &err);
679 	if (!fi) {
680 		inode_dec_link_count(inode);
681 		discard_new_inode(inode);
682 		goto out;
683 	}
684 	set_nlink(inode, 2);
685 	cfi.icb.extLength = cpu_to_le32(inode->i_sb->s_blocksize);
686 	cfi.icb.extLocation = cpu_to_lelb(dinfo->i_location);
687 	*(__le32 *)((struct allocDescImpUse *)cfi.icb.impUse)->impUse =
688 		cpu_to_le32(dinfo->i_unique & 0x00000000FFFFFFFFUL);
689 	cfi.fileCharacteristics =
690 			FID_FILE_CHAR_DIRECTORY | FID_FILE_CHAR_PARENT;
691 	udf_write_fi(inode, &cfi, fi, &fibh, NULL, NULL);
692 	brelse(fibh.sbh);
693 	mark_inode_dirty(inode);
694 
695 	fi = udf_add_entry(dir, dentry, &fibh, &cfi, &err);
696 	if (!fi) {
697 		clear_nlink(inode);
698 		mark_inode_dirty(inode);
699 		discard_new_inode(inode);
700 		goto out;
701 	}
702 	cfi.icb.extLength = cpu_to_le32(inode->i_sb->s_blocksize);
703 	cfi.icb.extLocation = cpu_to_lelb(iinfo->i_location);
704 	*(__le32 *)((struct allocDescImpUse *)cfi.icb.impUse)->impUse =
705 		cpu_to_le32(iinfo->i_unique & 0x00000000FFFFFFFFUL);
706 	cfi.fileCharacteristics |= FID_FILE_CHAR_DIRECTORY;
707 	udf_write_fi(dir, &cfi, fi, &fibh, NULL, NULL);
708 	inc_nlink(dir);
709 	dir->i_ctime = dir->i_mtime = current_time(dir);
710 	mark_inode_dirty(dir);
711 	d_instantiate_new(dentry, inode);
712 	if (fibh.sbh != fibh.ebh)
713 		brelse(fibh.ebh);
714 	brelse(fibh.sbh);
715 	err = 0;
716 
717 out:
718 	return err;
719 }
720 
721 static int empty_dir(struct inode *dir)
722 {
723 	struct fileIdentDesc *fi, cfi;
724 	struct udf_fileident_bh fibh;
725 	loff_t f_pos;
726 	loff_t size = udf_ext0_offset(dir) + dir->i_size;
727 	udf_pblk_t block;
728 	struct kernel_lb_addr eloc;
729 	uint32_t elen;
730 	sector_t offset;
731 	struct extent_position epos = {};
732 	struct udf_inode_info *dinfo = UDF_I(dir);
733 
734 	f_pos = udf_ext0_offset(dir);
735 	fibh.soffset = fibh.eoffset = f_pos & (dir->i_sb->s_blocksize - 1);
736 
737 	if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
738 		fibh.sbh = fibh.ebh = NULL;
739 	else if (inode_bmap(dir, f_pos >> dir->i_sb->s_blocksize_bits,
740 			      &epos, &eloc, &elen, &offset) ==
741 					(EXT_RECORDED_ALLOCATED >> 30)) {
742 		block = udf_get_lb_pblock(dir->i_sb, &eloc, offset);
743 		if ((++offset << dir->i_sb->s_blocksize_bits) < elen) {
744 			if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
745 				epos.offset -= sizeof(struct short_ad);
746 			else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
747 				epos.offset -= sizeof(struct long_ad);
748 		} else
749 			offset = 0;
750 
751 		fibh.sbh = fibh.ebh = udf_tread(dir->i_sb, block);
752 		if (!fibh.sbh) {
753 			brelse(epos.bh);
754 			return 0;
755 		}
756 	} else {
757 		brelse(epos.bh);
758 		return 0;
759 	}
760 
761 	while (f_pos < size) {
762 		fi = udf_fileident_read(dir, &f_pos, &fibh, &cfi, &epos, &eloc,
763 					&elen, &offset);
764 		if (!fi) {
765 			if (fibh.sbh != fibh.ebh)
766 				brelse(fibh.ebh);
767 			brelse(fibh.sbh);
768 			brelse(epos.bh);
769 			return 0;
770 		}
771 
772 		if (cfi.lengthFileIdent &&
773 		    (cfi.fileCharacteristics & FID_FILE_CHAR_DELETED) == 0) {
774 			if (fibh.sbh != fibh.ebh)
775 				brelse(fibh.ebh);
776 			brelse(fibh.sbh);
777 			brelse(epos.bh);
778 			return 0;
779 		}
780 	}
781 
782 	if (fibh.sbh != fibh.ebh)
783 		brelse(fibh.ebh);
784 	brelse(fibh.sbh);
785 	brelse(epos.bh);
786 
787 	return 1;
788 }
789 
790 static int udf_rmdir(struct inode *dir, struct dentry *dentry)
791 {
792 	int retval;
793 	struct inode *inode = d_inode(dentry);
794 	struct udf_fileident_bh fibh;
795 	struct fileIdentDesc *fi, cfi;
796 	struct kernel_lb_addr tloc;
797 
798 	retval = -ENOENT;
799 	fi = udf_find_entry(dir, &dentry->d_name, &fibh, &cfi);
800 	if (IS_ERR_OR_NULL(fi)) {
801 		if (fi)
802 			retval = PTR_ERR(fi);
803 		goto out;
804 	}
805 
806 	retval = -EIO;
807 	tloc = lelb_to_cpu(cfi.icb.extLocation);
808 	if (udf_get_lb_pblock(dir->i_sb, &tloc, 0) != inode->i_ino)
809 		goto end_rmdir;
810 	retval = -ENOTEMPTY;
811 	if (!empty_dir(inode))
812 		goto end_rmdir;
813 	retval = udf_delete_entry(dir, fi, &fibh, &cfi);
814 	if (retval)
815 		goto end_rmdir;
816 	if (inode->i_nlink != 2)
817 		udf_warn(inode->i_sb, "empty directory has nlink != 2 (%u)\n",
818 			 inode->i_nlink);
819 	clear_nlink(inode);
820 	inode->i_size = 0;
821 	inode_dec_link_count(dir);
822 	inode->i_ctime = dir->i_ctime = dir->i_mtime =
823 						current_time(inode);
824 	mark_inode_dirty(dir);
825 
826 end_rmdir:
827 	if (fibh.sbh != fibh.ebh)
828 		brelse(fibh.ebh);
829 	brelse(fibh.sbh);
830 
831 out:
832 	return retval;
833 }
834 
835 static int udf_unlink(struct inode *dir, struct dentry *dentry)
836 {
837 	int retval;
838 	struct inode *inode = d_inode(dentry);
839 	struct udf_fileident_bh fibh;
840 	struct fileIdentDesc *fi;
841 	struct fileIdentDesc cfi;
842 	struct kernel_lb_addr tloc;
843 
844 	retval = -ENOENT;
845 	fi = udf_find_entry(dir, &dentry->d_name, &fibh, &cfi);
846 
847 	if (IS_ERR_OR_NULL(fi)) {
848 		if (fi)
849 			retval = PTR_ERR(fi);
850 		goto out;
851 	}
852 
853 	retval = -EIO;
854 	tloc = lelb_to_cpu(cfi.icb.extLocation);
855 	if (udf_get_lb_pblock(dir->i_sb, &tloc, 0) != inode->i_ino)
856 		goto end_unlink;
857 
858 	if (!inode->i_nlink) {
859 		udf_debug("Deleting nonexistent file (%lu), %u\n",
860 			  inode->i_ino, inode->i_nlink);
861 		set_nlink(inode, 1);
862 	}
863 	retval = udf_delete_entry(dir, fi, &fibh, &cfi);
864 	if (retval)
865 		goto end_unlink;
866 	dir->i_ctime = dir->i_mtime = current_time(dir);
867 	mark_inode_dirty(dir);
868 	inode_dec_link_count(inode);
869 	inode->i_ctime = dir->i_ctime;
870 	retval = 0;
871 
872 end_unlink:
873 	if (fibh.sbh != fibh.ebh)
874 		brelse(fibh.ebh);
875 	brelse(fibh.sbh);
876 
877 out:
878 	return retval;
879 }
880 
881 static int udf_symlink(struct inode *dir, struct dentry *dentry,
882 		       const char *symname)
883 {
884 	struct inode *inode = udf_new_inode(dir, S_IFLNK | 0777);
885 	struct pathComponent *pc;
886 	const char *compstart;
887 	struct extent_position epos = {};
888 	int eoffset, elen = 0;
889 	uint8_t *ea;
890 	int err;
891 	udf_pblk_t block;
892 	unsigned char *name = NULL;
893 	int namelen;
894 	struct udf_inode_info *iinfo;
895 	struct super_block *sb = dir->i_sb;
896 
897 	if (IS_ERR(inode))
898 		return PTR_ERR(inode);
899 
900 	iinfo = UDF_I(inode);
901 	down_write(&iinfo->i_data_sem);
902 	name = kmalloc(UDF_NAME_LEN_CS0, GFP_NOFS);
903 	if (!name) {
904 		err = -ENOMEM;
905 		goto out_no_entry;
906 	}
907 
908 	inode->i_data.a_ops = &udf_symlink_aops;
909 	inode->i_op = &udf_symlink_inode_operations;
910 	inode_nohighmem(inode);
911 
912 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
913 		struct kernel_lb_addr eloc;
914 		uint32_t bsize;
915 
916 		block = udf_new_block(sb, inode,
917 				iinfo->i_location.partitionReferenceNum,
918 				iinfo->i_location.logicalBlockNum, &err);
919 		if (!block)
920 			goto out_no_entry;
921 		epos.block = iinfo->i_location;
922 		epos.offset = udf_file_entry_alloc_offset(inode);
923 		epos.bh = NULL;
924 		eloc.logicalBlockNum = block;
925 		eloc.partitionReferenceNum =
926 				iinfo->i_location.partitionReferenceNum;
927 		bsize = sb->s_blocksize;
928 		iinfo->i_lenExtents = bsize;
929 		udf_add_aext(inode, &epos, &eloc, bsize, 0);
930 		brelse(epos.bh);
931 
932 		block = udf_get_pblock(sb, block,
933 				iinfo->i_location.partitionReferenceNum,
934 				0);
935 		epos.bh = udf_tgetblk(sb, block);
936 		lock_buffer(epos.bh);
937 		memset(epos.bh->b_data, 0x00, bsize);
938 		set_buffer_uptodate(epos.bh);
939 		unlock_buffer(epos.bh);
940 		mark_buffer_dirty_inode(epos.bh, inode);
941 		ea = epos.bh->b_data + udf_ext0_offset(inode);
942 	} else
943 		ea = iinfo->i_ext.i_data + iinfo->i_lenEAttr;
944 
945 	eoffset = sb->s_blocksize - udf_ext0_offset(inode);
946 	pc = (struct pathComponent *)ea;
947 
948 	if (*symname == '/') {
949 		do {
950 			symname++;
951 		} while (*symname == '/');
952 
953 		pc->componentType = 1;
954 		pc->lengthComponentIdent = 0;
955 		pc->componentFileVersionNum = 0;
956 		elen += sizeof(struct pathComponent);
957 	}
958 
959 	err = -ENAMETOOLONG;
960 
961 	while (*symname) {
962 		if (elen + sizeof(struct pathComponent) > eoffset)
963 			goto out_no_entry;
964 
965 		pc = (struct pathComponent *)(ea + elen);
966 
967 		compstart = symname;
968 
969 		do {
970 			symname++;
971 		} while (*symname && *symname != '/');
972 
973 		pc->componentType = 5;
974 		pc->lengthComponentIdent = 0;
975 		pc->componentFileVersionNum = 0;
976 		if (compstart[0] == '.') {
977 			if ((symname - compstart) == 1)
978 				pc->componentType = 4;
979 			else if ((symname - compstart) == 2 &&
980 					compstart[1] == '.')
981 				pc->componentType = 3;
982 		}
983 
984 		if (pc->componentType == 5) {
985 			namelen = udf_put_filename(sb, compstart,
986 						   symname - compstart,
987 						   name, UDF_NAME_LEN_CS0);
988 			if (!namelen)
989 				goto out_no_entry;
990 
991 			if (elen + sizeof(struct pathComponent) + namelen >
992 					eoffset)
993 				goto out_no_entry;
994 			else
995 				pc->lengthComponentIdent = namelen;
996 
997 			memcpy(pc->componentIdent, name, namelen);
998 		}
999 
1000 		elen += sizeof(struct pathComponent) + pc->lengthComponentIdent;
1001 
1002 		if (*symname) {
1003 			do {
1004 				symname++;
1005 			} while (*symname == '/');
1006 		}
1007 	}
1008 
1009 	brelse(epos.bh);
1010 	inode->i_size = elen;
1011 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1012 		iinfo->i_lenAlloc = inode->i_size;
1013 	else
1014 		udf_truncate_tail_extent(inode);
1015 	mark_inode_dirty(inode);
1016 	up_write(&iinfo->i_data_sem);
1017 
1018 	err = udf_add_nondir(dentry, inode);
1019 out:
1020 	kfree(name);
1021 	return err;
1022 
1023 out_no_entry:
1024 	up_write(&iinfo->i_data_sem);
1025 	inode_dec_link_count(inode);
1026 	discard_new_inode(inode);
1027 	goto out;
1028 }
1029 
1030 static int udf_link(struct dentry *old_dentry, struct inode *dir,
1031 		    struct dentry *dentry)
1032 {
1033 	struct inode *inode = d_inode(old_dentry);
1034 	struct udf_fileident_bh fibh;
1035 	struct fileIdentDesc cfi, *fi;
1036 	int err;
1037 
1038 	fi = udf_add_entry(dir, dentry, &fibh, &cfi, &err);
1039 	if (!fi) {
1040 		return err;
1041 	}
1042 	cfi.icb.extLength = cpu_to_le32(inode->i_sb->s_blocksize);
1043 	cfi.icb.extLocation = cpu_to_lelb(UDF_I(inode)->i_location);
1044 	if (UDF_SB(inode->i_sb)->s_lvid_bh) {
1045 		*(__le32 *)((struct allocDescImpUse *)cfi.icb.impUse)->impUse =
1046 			cpu_to_le32(lvid_get_unique_id(inode->i_sb));
1047 	}
1048 	udf_write_fi(dir, &cfi, fi, &fibh, NULL, NULL);
1049 	if (UDF_I(dir)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1050 		mark_inode_dirty(dir);
1051 
1052 	if (fibh.sbh != fibh.ebh)
1053 		brelse(fibh.ebh);
1054 	brelse(fibh.sbh);
1055 	inc_nlink(inode);
1056 	inode->i_ctime = current_time(inode);
1057 	mark_inode_dirty(inode);
1058 	dir->i_ctime = dir->i_mtime = current_time(dir);
1059 	mark_inode_dirty(dir);
1060 	ihold(inode);
1061 	d_instantiate(dentry, inode);
1062 
1063 	return 0;
1064 }
1065 
1066 /* Anybody can rename anything with this: the permission checks are left to the
1067  * higher-level routines.
1068  */
1069 static int udf_rename(struct inode *old_dir, struct dentry *old_dentry,
1070 		      struct inode *new_dir, struct dentry *new_dentry,
1071 		      unsigned int flags)
1072 {
1073 	struct inode *old_inode = d_inode(old_dentry);
1074 	struct inode *new_inode = d_inode(new_dentry);
1075 	struct udf_fileident_bh ofibh, nfibh;
1076 	struct fileIdentDesc *ofi = NULL, *nfi = NULL, *dir_fi = NULL;
1077 	struct fileIdentDesc ocfi, ncfi;
1078 	struct buffer_head *dir_bh = NULL;
1079 	int retval = -ENOENT;
1080 	struct kernel_lb_addr tloc;
1081 	struct udf_inode_info *old_iinfo = UDF_I(old_inode);
1082 
1083 	if (flags & ~RENAME_NOREPLACE)
1084 		return -EINVAL;
1085 
1086 	ofi = udf_find_entry(old_dir, &old_dentry->d_name, &ofibh, &ocfi);
1087 	if (IS_ERR(ofi)) {
1088 		retval = PTR_ERR(ofi);
1089 		goto end_rename;
1090 	}
1091 
1092 	if (ofibh.sbh != ofibh.ebh)
1093 		brelse(ofibh.ebh);
1094 
1095 	brelse(ofibh.sbh);
1096 	tloc = lelb_to_cpu(ocfi.icb.extLocation);
1097 	if (!ofi || udf_get_lb_pblock(old_dir->i_sb, &tloc, 0)
1098 	    != old_inode->i_ino)
1099 		goto end_rename;
1100 
1101 	nfi = udf_find_entry(new_dir, &new_dentry->d_name, &nfibh, &ncfi);
1102 	if (IS_ERR(nfi)) {
1103 		retval = PTR_ERR(nfi);
1104 		goto end_rename;
1105 	}
1106 	if (nfi && !new_inode) {
1107 		if (nfibh.sbh != nfibh.ebh)
1108 			brelse(nfibh.ebh);
1109 		brelse(nfibh.sbh);
1110 		nfi = NULL;
1111 	}
1112 	if (S_ISDIR(old_inode->i_mode)) {
1113 		int offset = udf_ext0_offset(old_inode);
1114 
1115 		if (new_inode) {
1116 			retval = -ENOTEMPTY;
1117 			if (!empty_dir(new_inode))
1118 				goto end_rename;
1119 		}
1120 		retval = -EIO;
1121 		if (old_iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1122 			dir_fi = udf_get_fileident(
1123 					old_iinfo->i_ext.i_data -
1124 					  (old_iinfo->i_efe ?
1125 					   sizeof(struct extendedFileEntry) :
1126 					   sizeof(struct fileEntry)),
1127 					old_inode->i_sb->s_blocksize, &offset);
1128 		} else {
1129 			dir_bh = udf_bread(old_inode, 0, 0, &retval);
1130 			if (!dir_bh)
1131 				goto end_rename;
1132 			dir_fi = udf_get_fileident(dir_bh->b_data,
1133 					old_inode->i_sb->s_blocksize, &offset);
1134 		}
1135 		if (!dir_fi)
1136 			goto end_rename;
1137 		tloc = lelb_to_cpu(dir_fi->icb.extLocation);
1138 		if (udf_get_lb_pblock(old_inode->i_sb, &tloc, 0) !=
1139 				old_dir->i_ino)
1140 			goto end_rename;
1141 	}
1142 	if (!nfi) {
1143 		nfi = udf_add_entry(new_dir, new_dentry, &nfibh, &ncfi,
1144 				    &retval);
1145 		if (!nfi)
1146 			goto end_rename;
1147 	}
1148 
1149 	/*
1150 	 * Like most other Unix systems, set the ctime for inodes on a
1151 	 * rename.
1152 	 */
1153 	old_inode->i_ctime = current_time(old_inode);
1154 	mark_inode_dirty(old_inode);
1155 
1156 	/*
1157 	 * ok, that's it
1158 	 */
1159 	ncfi.fileVersionNum = ocfi.fileVersionNum;
1160 	ncfi.fileCharacteristics = ocfi.fileCharacteristics;
1161 	memcpy(&(ncfi.icb), &(ocfi.icb), sizeof(ocfi.icb));
1162 	udf_write_fi(new_dir, &ncfi, nfi, &nfibh, NULL, NULL);
1163 
1164 	/* The old fid may have moved - find it again */
1165 	ofi = udf_find_entry(old_dir, &old_dentry->d_name, &ofibh, &ocfi);
1166 	udf_delete_entry(old_dir, ofi, &ofibh, &ocfi);
1167 
1168 	if (new_inode) {
1169 		new_inode->i_ctime = current_time(new_inode);
1170 		inode_dec_link_count(new_inode);
1171 	}
1172 	old_dir->i_ctime = old_dir->i_mtime = current_time(old_dir);
1173 	new_dir->i_ctime = new_dir->i_mtime = current_time(new_dir);
1174 	mark_inode_dirty(old_dir);
1175 	mark_inode_dirty(new_dir);
1176 
1177 	if (dir_fi) {
1178 		dir_fi->icb.extLocation = cpu_to_lelb(UDF_I(new_dir)->i_location);
1179 		udf_update_tag((char *)dir_fi, udf_dir_entry_len(dir_fi));
1180 		if (old_iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1181 			mark_inode_dirty(old_inode);
1182 		else
1183 			mark_buffer_dirty_inode(dir_bh, old_inode);
1184 
1185 		inode_dec_link_count(old_dir);
1186 		if (new_inode)
1187 			inode_dec_link_count(new_inode);
1188 		else {
1189 			inc_nlink(new_dir);
1190 			mark_inode_dirty(new_dir);
1191 		}
1192 	}
1193 
1194 	if (ofi) {
1195 		if (ofibh.sbh != ofibh.ebh)
1196 			brelse(ofibh.ebh);
1197 		brelse(ofibh.sbh);
1198 	}
1199 
1200 	retval = 0;
1201 
1202 end_rename:
1203 	brelse(dir_bh);
1204 	if (nfi) {
1205 		if (nfibh.sbh != nfibh.ebh)
1206 			brelse(nfibh.ebh);
1207 		brelse(nfibh.sbh);
1208 	}
1209 
1210 	return retval;
1211 }
1212 
1213 static struct dentry *udf_get_parent(struct dentry *child)
1214 {
1215 	struct kernel_lb_addr tloc;
1216 	struct inode *inode = NULL;
1217 	struct qstr dotdot = QSTR_INIT("..", 2);
1218 	struct fileIdentDesc cfi;
1219 	struct udf_fileident_bh fibh;
1220 
1221 	if (!udf_find_entry(d_inode(child), &dotdot, &fibh, &cfi))
1222 		return ERR_PTR(-EACCES);
1223 
1224 	if (fibh.sbh != fibh.ebh)
1225 		brelse(fibh.ebh);
1226 	brelse(fibh.sbh);
1227 
1228 	tloc = lelb_to_cpu(cfi.icb.extLocation);
1229 	inode = udf_iget(child->d_sb, &tloc);
1230 	if (IS_ERR(inode))
1231 		return ERR_CAST(inode);
1232 
1233 	return d_obtain_alias(inode);
1234 }
1235 
1236 
1237 static struct dentry *udf_nfs_get_inode(struct super_block *sb, u32 block,
1238 					u16 partref, __u32 generation)
1239 {
1240 	struct inode *inode;
1241 	struct kernel_lb_addr loc;
1242 
1243 	if (block == 0)
1244 		return ERR_PTR(-ESTALE);
1245 
1246 	loc.logicalBlockNum = block;
1247 	loc.partitionReferenceNum = partref;
1248 	inode = udf_iget(sb, &loc);
1249 
1250 	if (IS_ERR(inode))
1251 		return ERR_CAST(inode);
1252 
1253 	if (generation && inode->i_generation != generation) {
1254 		iput(inode);
1255 		return ERR_PTR(-ESTALE);
1256 	}
1257 	return d_obtain_alias(inode);
1258 }
1259 
1260 static struct dentry *udf_fh_to_dentry(struct super_block *sb,
1261 				       struct fid *fid, int fh_len, int fh_type)
1262 {
1263 	if (fh_len < 3 ||
1264 	    (fh_type != FILEID_UDF_WITH_PARENT &&
1265 	     fh_type != FILEID_UDF_WITHOUT_PARENT))
1266 		return NULL;
1267 
1268 	return udf_nfs_get_inode(sb, fid->udf.block, fid->udf.partref,
1269 			fid->udf.generation);
1270 }
1271 
1272 static struct dentry *udf_fh_to_parent(struct super_block *sb,
1273 				       struct fid *fid, int fh_len, int fh_type)
1274 {
1275 	if (fh_len < 5 || fh_type != FILEID_UDF_WITH_PARENT)
1276 		return NULL;
1277 
1278 	return udf_nfs_get_inode(sb, fid->udf.parent_block,
1279 				 fid->udf.parent_partref,
1280 				 fid->udf.parent_generation);
1281 }
1282 static int udf_encode_fh(struct inode *inode, __u32 *fh, int *lenp,
1283 			 struct inode *parent)
1284 {
1285 	int len = *lenp;
1286 	struct kernel_lb_addr location = UDF_I(inode)->i_location;
1287 	struct fid *fid = (struct fid *)fh;
1288 	int type = FILEID_UDF_WITHOUT_PARENT;
1289 
1290 	if (parent && (len < 5)) {
1291 		*lenp = 5;
1292 		return FILEID_INVALID;
1293 	} else if (len < 3) {
1294 		*lenp = 3;
1295 		return FILEID_INVALID;
1296 	}
1297 
1298 	*lenp = 3;
1299 	fid->udf.block = location.logicalBlockNum;
1300 	fid->udf.partref = location.partitionReferenceNum;
1301 	fid->udf.parent_partref = 0;
1302 	fid->udf.generation = inode->i_generation;
1303 
1304 	if (parent) {
1305 		location = UDF_I(parent)->i_location;
1306 		fid->udf.parent_block = location.logicalBlockNum;
1307 		fid->udf.parent_partref = location.partitionReferenceNum;
1308 		fid->udf.parent_generation = inode->i_generation;
1309 		*lenp = 5;
1310 		type = FILEID_UDF_WITH_PARENT;
1311 	}
1312 
1313 	return type;
1314 }
1315 
1316 const struct export_operations udf_export_ops = {
1317 	.encode_fh	= udf_encode_fh,
1318 	.fh_to_dentry   = udf_fh_to_dentry,
1319 	.fh_to_parent   = udf_fh_to_parent,
1320 	.get_parent     = udf_get_parent,
1321 };
1322 
1323 const struct inode_operations udf_dir_inode_operations = {
1324 	.lookup				= udf_lookup,
1325 	.create				= udf_create,
1326 	.link				= udf_link,
1327 	.unlink				= udf_unlink,
1328 	.symlink			= udf_symlink,
1329 	.mkdir				= udf_mkdir,
1330 	.rmdir				= udf_rmdir,
1331 	.mknod				= udf_mknod,
1332 	.rename				= udf_rename,
1333 	.tmpfile			= udf_tmpfile,
1334 };
1335