xref: /openbmc/linux/fs/udf/namei.c (revision 13dd8710)
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_data + fibh->soffset -
464 					 udf_ext0_offset(dir) +
465 					 dinfo->i_lenEAttr);
466 		} else {
467 			block = eloc.logicalBlockNum +
468 					((elen - 1) >>
469 						dir->i_sb->s_blocksize_bits);
470 			fi = (struct fileIdentDesc *)
471 				(fibh->sbh->b_data + fibh->soffset);
472 		}
473 	} else {
474 		/* Round up last extent in the file */
475 		elen = (elen + sb->s_blocksize - 1) & ~(sb->s_blocksize - 1);
476 		if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
477 			epos.offset -= sizeof(struct short_ad);
478 		else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
479 			epos.offset -= sizeof(struct long_ad);
480 		udf_write_aext(dir, &epos, &eloc, elen, 1);
481 		dinfo->i_lenExtents = (dinfo->i_lenExtents + sb->s_blocksize
482 					- 1) & ~(sb->s_blocksize - 1);
483 
484 		fibh->soffset = fibh->eoffset - sb->s_blocksize;
485 		fibh->eoffset += nfidlen - sb->s_blocksize;
486 		if (fibh->sbh != fibh->ebh) {
487 			brelse(fibh->sbh);
488 			fibh->sbh = fibh->ebh;
489 		}
490 
491 		block = eloc.logicalBlockNum + ((elen - 1) >>
492 						dir->i_sb->s_blocksize_bits);
493 		fibh->ebh = udf_bread(dir,
494 				f_pos >> dir->i_sb->s_blocksize_bits, 1, err);
495 		if (!fibh->ebh)
496 			goto out_err;
497 		/* Extents could have been merged, invalidate our position */
498 		brelse(epos.bh);
499 		epos.bh = NULL;
500 		epos.block = dinfo->i_location;
501 		epos.offset = udf_file_entry_alloc_offset(dir);
502 
503 		if (!fibh->soffset) {
504 			/* Find the freshly allocated block */
505 			while (udf_next_aext(dir, &epos, &eloc, &elen, 1) ==
506 				(EXT_RECORDED_ALLOCATED >> 30))
507 				;
508 			block = eloc.logicalBlockNum + ((elen - 1) >>
509 					dir->i_sb->s_blocksize_bits);
510 			brelse(fibh->sbh);
511 			fibh->sbh = fibh->ebh;
512 			fi = (struct fileIdentDesc *)(fibh->sbh->b_data);
513 		} else {
514 			fi = (struct fileIdentDesc *)
515 				(fibh->sbh->b_data + sb->s_blocksize +
516 					fibh->soffset);
517 		}
518 	}
519 
520 	memset(cfi, 0, sizeof(struct fileIdentDesc));
521 	if (UDF_SB(sb)->s_udfrev >= 0x0200)
522 		udf_new_tag((char *)cfi, TAG_IDENT_FID, 3, 1, block,
523 			    sizeof(struct tag));
524 	else
525 		udf_new_tag((char *)cfi, TAG_IDENT_FID, 2, 1, block,
526 			    sizeof(struct tag));
527 	cfi->fileVersionNum = cpu_to_le16(1);
528 	cfi->lengthFileIdent = namelen;
529 	cfi->lengthOfImpUse = cpu_to_le16(0);
530 	if (!udf_write_fi(dir, cfi, fi, fibh, NULL, name)) {
531 		dir->i_size += nfidlen;
532 		if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
533 			dinfo->i_lenAlloc += nfidlen;
534 		else {
535 			/* Find the last extent and truncate it to proper size */
536 			while (udf_next_aext(dir, &epos, &eloc, &elen, 1) ==
537 				(EXT_RECORDED_ALLOCATED >> 30))
538 				;
539 			elen -= dinfo->i_lenExtents - dir->i_size;
540 			if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
541 				epos.offset -= sizeof(struct short_ad);
542 			else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
543 				epos.offset -= sizeof(struct long_ad);
544 			udf_write_aext(dir, &epos, &eloc, elen, 1);
545 			dinfo->i_lenExtents = dir->i_size;
546 		}
547 
548 		mark_inode_dirty(dir);
549 		goto out_ok;
550 	} else {
551 		*err = -EIO;
552 		goto out_err;
553 	}
554 
555 out_err:
556 	fi = NULL;
557 	if (fibh->sbh != fibh->ebh)
558 		brelse(fibh->ebh);
559 	brelse(fibh->sbh);
560 out_ok:
561 	brelse(epos.bh);
562 	kfree(name);
563 	return fi;
564 }
565 
566 static int udf_delete_entry(struct inode *inode, struct fileIdentDesc *fi,
567 			    struct udf_fileident_bh *fibh,
568 			    struct fileIdentDesc *cfi)
569 {
570 	cfi->fileCharacteristics |= FID_FILE_CHAR_DELETED;
571 
572 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT))
573 		memset(&(cfi->icb), 0x00, sizeof(struct long_ad));
574 
575 	return udf_write_fi(inode, cfi, fi, fibh, NULL, NULL);
576 }
577 
578 static int udf_add_nondir(struct dentry *dentry, struct inode *inode)
579 {
580 	struct udf_inode_info *iinfo = UDF_I(inode);
581 	struct inode *dir = d_inode(dentry->d_parent);
582 	struct udf_fileident_bh fibh;
583 	struct fileIdentDesc cfi, *fi;
584 	int err;
585 
586 	fi = udf_add_entry(dir, dentry, &fibh, &cfi, &err);
587 	if (unlikely(!fi)) {
588 		inode_dec_link_count(inode);
589 		discard_new_inode(inode);
590 		return err;
591 	}
592 	cfi.icb.extLength = cpu_to_le32(inode->i_sb->s_blocksize);
593 	cfi.icb.extLocation = cpu_to_lelb(iinfo->i_location);
594 	*(__le32 *)((struct allocDescImpUse *)cfi.icb.impUse)->impUse =
595 		cpu_to_le32(iinfo->i_unique & 0x00000000FFFFFFFFUL);
596 	udf_write_fi(dir, &cfi, fi, &fibh, NULL, NULL);
597 	dir->i_ctime = dir->i_mtime = current_time(dir);
598 	mark_inode_dirty(dir);
599 	if (fibh.sbh != fibh.ebh)
600 		brelse(fibh.ebh);
601 	brelse(fibh.sbh);
602 	d_instantiate_new(dentry, inode);
603 
604 	return 0;
605 }
606 
607 static int udf_create(struct inode *dir, struct dentry *dentry, umode_t mode,
608 		      bool excl)
609 {
610 	struct inode *inode = udf_new_inode(dir, mode);
611 
612 	if (IS_ERR(inode))
613 		return PTR_ERR(inode);
614 
615 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
616 		inode->i_data.a_ops = &udf_adinicb_aops;
617 	else
618 		inode->i_data.a_ops = &udf_aops;
619 	inode->i_op = &udf_file_inode_operations;
620 	inode->i_fop = &udf_file_operations;
621 	mark_inode_dirty(inode);
622 
623 	return udf_add_nondir(dentry, inode);
624 }
625 
626 static int udf_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
627 {
628 	struct inode *inode = udf_new_inode(dir, mode);
629 
630 	if (IS_ERR(inode))
631 		return PTR_ERR(inode);
632 
633 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
634 		inode->i_data.a_ops = &udf_adinicb_aops;
635 	else
636 		inode->i_data.a_ops = &udf_aops;
637 	inode->i_op = &udf_file_inode_operations;
638 	inode->i_fop = &udf_file_operations;
639 	mark_inode_dirty(inode);
640 	d_tmpfile(dentry, inode);
641 	unlock_new_inode(inode);
642 	return 0;
643 }
644 
645 static int udf_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
646 		     dev_t rdev)
647 {
648 	struct inode *inode;
649 
650 	if (!old_valid_dev(rdev))
651 		return -EINVAL;
652 
653 	inode = udf_new_inode(dir, mode);
654 	if (IS_ERR(inode))
655 		return PTR_ERR(inode);
656 
657 	init_special_inode(inode, mode, rdev);
658 	return udf_add_nondir(dentry, inode);
659 }
660 
661 static int udf_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
662 {
663 	struct inode *inode;
664 	struct udf_fileident_bh fibh;
665 	struct fileIdentDesc cfi, *fi;
666 	int err;
667 	struct udf_inode_info *dinfo = UDF_I(dir);
668 	struct udf_inode_info *iinfo;
669 
670 	inode = udf_new_inode(dir, S_IFDIR | mode);
671 	if (IS_ERR(inode))
672 		return PTR_ERR(inode);
673 
674 	iinfo = UDF_I(inode);
675 	inode->i_op = &udf_dir_inode_operations;
676 	inode->i_fop = &udf_dir_operations;
677 	fi = udf_add_entry(inode, NULL, &fibh, &cfi, &err);
678 	if (!fi) {
679 		inode_dec_link_count(inode);
680 		discard_new_inode(inode);
681 		goto out;
682 	}
683 	set_nlink(inode, 2);
684 	cfi.icb.extLength = cpu_to_le32(inode->i_sb->s_blocksize);
685 	cfi.icb.extLocation = cpu_to_lelb(dinfo->i_location);
686 	*(__le32 *)((struct allocDescImpUse *)cfi.icb.impUse)->impUse =
687 		cpu_to_le32(dinfo->i_unique & 0x00000000FFFFFFFFUL);
688 	cfi.fileCharacteristics =
689 			FID_FILE_CHAR_DIRECTORY | FID_FILE_CHAR_PARENT;
690 	udf_write_fi(inode, &cfi, fi, &fibh, NULL, NULL);
691 	brelse(fibh.sbh);
692 	mark_inode_dirty(inode);
693 
694 	fi = udf_add_entry(dir, dentry, &fibh, &cfi, &err);
695 	if (!fi) {
696 		clear_nlink(inode);
697 		mark_inode_dirty(inode);
698 		discard_new_inode(inode);
699 		goto out;
700 	}
701 	cfi.icb.extLength = cpu_to_le32(inode->i_sb->s_blocksize);
702 	cfi.icb.extLocation = cpu_to_lelb(iinfo->i_location);
703 	*(__le32 *)((struct allocDescImpUse *)cfi.icb.impUse)->impUse =
704 		cpu_to_le32(iinfo->i_unique & 0x00000000FFFFFFFFUL);
705 	cfi.fileCharacteristics |= FID_FILE_CHAR_DIRECTORY;
706 	udf_write_fi(dir, &cfi, fi, &fibh, NULL, NULL);
707 	inc_nlink(dir);
708 	dir->i_ctime = dir->i_mtime = current_time(dir);
709 	mark_inode_dirty(dir);
710 	d_instantiate_new(dentry, inode);
711 	if (fibh.sbh != fibh.ebh)
712 		brelse(fibh.ebh);
713 	brelse(fibh.sbh);
714 	err = 0;
715 
716 out:
717 	return err;
718 }
719 
720 static int empty_dir(struct inode *dir)
721 {
722 	struct fileIdentDesc *fi, cfi;
723 	struct udf_fileident_bh fibh;
724 	loff_t f_pos;
725 	loff_t size = udf_ext0_offset(dir) + dir->i_size;
726 	udf_pblk_t block;
727 	struct kernel_lb_addr eloc;
728 	uint32_t elen;
729 	sector_t offset;
730 	struct extent_position epos = {};
731 	struct udf_inode_info *dinfo = UDF_I(dir);
732 
733 	f_pos = udf_ext0_offset(dir);
734 	fibh.soffset = fibh.eoffset = f_pos & (dir->i_sb->s_blocksize - 1);
735 
736 	if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
737 		fibh.sbh = fibh.ebh = NULL;
738 	else if (inode_bmap(dir, f_pos >> dir->i_sb->s_blocksize_bits,
739 			      &epos, &eloc, &elen, &offset) ==
740 					(EXT_RECORDED_ALLOCATED >> 30)) {
741 		block = udf_get_lb_pblock(dir->i_sb, &eloc, offset);
742 		if ((++offset << dir->i_sb->s_blocksize_bits) < elen) {
743 			if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
744 				epos.offset -= sizeof(struct short_ad);
745 			else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
746 				epos.offset -= sizeof(struct long_ad);
747 		} else
748 			offset = 0;
749 
750 		fibh.sbh = fibh.ebh = udf_tread(dir->i_sb, block);
751 		if (!fibh.sbh) {
752 			brelse(epos.bh);
753 			return 0;
754 		}
755 	} else {
756 		brelse(epos.bh);
757 		return 0;
758 	}
759 
760 	while (f_pos < size) {
761 		fi = udf_fileident_read(dir, &f_pos, &fibh, &cfi, &epos, &eloc,
762 					&elen, &offset);
763 		if (!fi) {
764 			if (fibh.sbh != fibh.ebh)
765 				brelse(fibh.ebh);
766 			brelse(fibh.sbh);
767 			brelse(epos.bh);
768 			return 0;
769 		}
770 
771 		if (cfi.lengthFileIdent &&
772 		    (cfi.fileCharacteristics & FID_FILE_CHAR_DELETED) == 0) {
773 			if (fibh.sbh != fibh.ebh)
774 				brelse(fibh.ebh);
775 			brelse(fibh.sbh);
776 			brelse(epos.bh);
777 			return 0;
778 		}
779 	}
780 
781 	if (fibh.sbh != fibh.ebh)
782 		brelse(fibh.ebh);
783 	brelse(fibh.sbh);
784 	brelse(epos.bh);
785 
786 	return 1;
787 }
788 
789 static int udf_rmdir(struct inode *dir, struct dentry *dentry)
790 {
791 	int retval;
792 	struct inode *inode = d_inode(dentry);
793 	struct udf_fileident_bh fibh;
794 	struct fileIdentDesc *fi, cfi;
795 	struct kernel_lb_addr tloc;
796 
797 	retval = -ENOENT;
798 	fi = udf_find_entry(dir, &dentry->d_name, &fibh, &cfi);
799 	if (IS_ERR_OR_NULL(fi)) {
800 		if (fi)
801 			retval = PTR_ERR(fi);
802 		goto out;
803 	}
804 
805 	retval = -EIO;
806 	tloc = lelb_to_cpu(cfi.icb.extLocation);
807 	if (udf_get_lb_pblock(dir->i_sb, &tloc, 0) != inode->i_ino)
808 		goto end_rmdir;
809 	retval = -ENOTEMPTY;
810 	if (!empty_dir(inode))
811 		goto end_rmdir;
812 	retval = udf_delete_entry(dir, fi, &fibh, &cfi);
813 	if (retval)
814 		goto end_rmdir;
815 	if (inode->i_nlink != 2)
816 		udf_warn(inode->i_sb, "empty directory has nlink != 2 (%u)\n",
817 			 inode->i_nlink);
818 	clear_nlink(inode);
819 	inode->i_size = 0;
820 	inode_dec_link_count(dir);
821 	inode->i_ctime = dir->i_ctime = dir->i_mtime =
822 						current_time(inode);
823 	mark_inode_dirty(dir);
824 
825 end_rmdir:
826 	if (fibh.sbh != fibh.ebh)
827 		brelse(fibh.ebh);
828 	brelse(fibh.sbh);
829 
830 out:
831 	return retval;
832 }
833 
834 static int udf_unlink(struct inode *dir, struct dentry *dentry)
835 {
836 	int retval;
837 	struct inode *inode = d_inode(dentry);
838 	struct udf_fileident_bh fibh;
839 	struct fileIdentDesc *fi;
840 	struct fileIdentDesc cfi;
841 	struct kernel_lb_addr tloc;
842 
843 	retval = -ENOENT;
844 	fi = udf_find_entry(dir, &dentry->d_name, &fibh, &cfi);
845 
846 	if (IS_ERR_OR_NULL(fi)) {
847 		if (fi)
848 			retval = PTR_ERR(fi);
849 		goto out;
850 	}
851 
852 	retval = -EIO;
853 	tloc = lelb_to_cpu(cfi.icb.extLocation);
854 	if (udf_get_lb_pblock(dir->i_sb, &tloc, 0) != inode->i_ino)
855 		goto end_unlink;
856 
857 	if (!inode->i_nlink) {
858 		udf_debug("Deleting nonexistent file (%lu), %u\n",
859 			  inode->i_ino, inode->i_nlink);
860 		set_nlink(inode, 1);
861 	}
862 	retval = udf_delete_entry(dir, fi, &fibh, &cfi);
863 	if (retval)
864 		goto end_unlink;
865 	dir->i_ctime = dir->i_mtime = current_time(dir);
866 	mark_inode_dirty(dir);
867 	inode_dec_link_count(inode);
868 	inode->i_ctime = dir->i_ctime;
869 	retval = 0;
870 
871 end_unlink:
872 	if (fibh.sbh != fibh.ebh)
873 		brelse(fibh.ebh);
874 	brelse(fibh.sbh);
875 
876 out:
877 	return retval;
878 }
879 
880 static int udf_symlink(struct inode *dir, struct dentry *dentry,
881 		       const char *symname)
882 {
883 	struct inode *inode = udf_new_inode(dir, S_IFLNK | 0777);
884 	struct pathComponent *pc;
885 	const char *compstart;
886 	struct extent_position epos = {};
887 	int eoffset, elen = 0;
888 	uint8_t *ea;
889 	int err;
890 	udf_pblk_t block;
891 	unsigned char *name = NULL;
892 	int namelen;
893 	struct udf_inode_info *iinfo;
894 	struct super_block *sb = dir->i_sb;
895 
896 	if (IS_ERR(inode))
897 		return PTR_ERR(inode);
898 
899 	iinfo = UDF_I(inode);
900 	down_write(&iinfo->i_data_sem);
901 	name = kmalloc(UDF_NAME_LEN_CS0, GFP_NOFS);
902 	if (!name) {
903 		err = -ENOMEM;
904 		goto out_no_entry;
905 	}
906 
907 	inode->i_data.a_ops = &udf_symlink_aops;
908 	inode->i_op = &udf_symlink_inode_operations;
909 	inode_nohighmem(inode);
910 
911 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
912 		struct kernel_lb_addr eloc;
913 		uint32_t bsize;
914 
915 		block = udf_new_block(sb, inode,
916 				iinfo->i_location.partitionReferenceNum,
917 				iinfo->i_location.logicalBlockNum, &err);
918 		if (!block)
919 			goto out_no_entry;
920 		epos.block = iinfo->i_location;
921 		epos.offset = udf_file_entry_alloc_offset(inode);
922 		epos.bh = NULL;
923 		eloc.logicalBlockNum = block;
924 		eloc.partitionReferenceNum =
925 				iinfo->i_location.partitionReferenceNum;
926 		bsize = sb->s_blocksize;
927 		iinfo->i_lenExtents = bsize;
928 		udf_add_aext(inode, &epos, &eloc, bsize, 0);
929 		brelse(epos.bh);
930 
931 		block = udf_get_pblock(sb, block,
932 				iinfo->i_location.partitionReferenceNum,
933 				0);
934 		epos.bh = udf_tgetblk(sb, block);
935 		lock_buffer(epos.bh);
936 		memset(epos.bh->b_data, 0x00, bsize);
937 		set_buffer_uptodate(epos.bh);
938 		unlock_buffer(epos.bh);
939 		mark_buffer_dirty_inode(epos.bh, inode);
940 		ea = epos.bh->b_data + udf_ext0_offset(inode);
941 	} else
942 		ea = iinfo->i_data + iinfo->i_lenEAttr;
943 
944 	eoffset = sb->s_blocksize - udf_ext0_offset(inode);
945 	pc = (struct pathComponent *)ea;
946 
947 	if (*symname == '/') {
948 		do {
949 			symname++;
950 		} while (*symname == '/');
951 
952 		pc->componentType = 1;
953 		pc->lengthComponentIdent = 0;
954 		pc->componentFileVersionNum = 0;
955 		elen += sizeof(struct pathComponent);
956 	}
957 
958 	err = -ENAMETOOLONG;
959 
960 	while (*symname) {
961 		if (elen + sizeof(struct pathComponent) > eoffset)
962 			goto out_no_entry;
963 
964 		pc = (struct pathComponent *)(ea + elen);
965 
966 		compstart = symname;
967 
968 		do {
969 			symname++;
970 		} while (*symname && *symname != '/');
971 
972 		pc->componentType = 5;
973 		pc->lengthComponentIdent = 0;
974 		pc->componentFileVersionNum = 0;
975 		if (compstart[0] == '.') {
976 			if ((symname - compstart) == 1)
977 				pc->componentType = 4;
978 			else if ((symname - compstart) == 2 &&
979 					compstart[1] == '.')
980 				pc->componentType = 3;
981 		}
982 
983 		if (pc->componentType == 5) {
984 			namelen = udf_put_filename(sb, compstart,
985 						   symname - compstart,
986 						   name, UDF_NAME_LEN_CS0);
987 			if (!namelen)
988 				goto out_no_entry;
989 
990 			if (elen + sizeof(struct pathComponent) + namelen >
991 					eoffset)
992 				goto out_no_entry;
993 			else
994 				pc->lengthComponentIdent = namelen;
995 
996 			memcpy(pc->componentIdent, name, namelen);
997 		}
998 
999 		elen += sizeof(struct pathComponent) + pc->lengthComponentIdent;
1000 
1001 		if (*symname) {
1002 			do {
1003 				symname++;
1004 			} while (*symname == '/');
1005 		}
1006 	}
1007 
1008 	brelse(epos.bh);
1009 	inode->i_size = elen;
1010 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1011 		iinfo->i_lenAlloc = inode->i_size;
1012 	else
1013 		udf_truncate_tail_extent(inode);
1014 	mark_inode_dirty(inode);
1015 	up_write(&iinfo->i_data_sem);
1016 
1017 	err = udf_add_nondir(dentry, inode);
1018 out:
1019 	kfree(name);
1020 	return err;
1021 
1022 out_no_entry:
1023 	up_write(&iinfo->i_data_sem);
1024 	inode_dec_link_count(inode);
1025 	discard_new_inode(inode);
1026 	goto out;
1027 }
1028 
1029 static int udf_link(struct dentry *old_dentry, struct inode *dir,
1030 		    struct dentry *dentry)
1031 {
1032 	struct inode *inode = d_inode(old_dentry);
1033 	struct udf_fileident_bh fibh;
1034 	struct fileIdentDesc cfi, *fi;
1035 	int err;
1036 
1037 	fi = udf_add_entry(dir, dentry, &fibh, &cfi, &err);
1038 	if (!fi) {
1039 		return err;
1040 	}
1041 	cfi.icb.extLength = cpu_to_le32(inode->i_sb->s_blocksize);
1042 	cfi.icb.extLocation = cpu_to_lelb(UDF_I(inode)->i_location);
1043 	if (UDF_SB(inode->i_sb)->s_lvid_bh) {
1044 		*(__le32 *)((struct allocDescImpUse *)cfi.icb.impUse)->impUse =
1045 			cpu_to_le32(lvid_get_unique_id(inode->i_sb));
1046 	}
1047 	udf_write_fi(dir, &cfi, fi, &fibh, NULL, NULL);
1048 	if (UDF_I(dir)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1049 		mark_inode_dirty(dir);
1050 
1051 	if (fibh.sbh != fibh.ebh)
1052 		brelse(fibh.ebh);
1053 	brelse(fibh.sbh);
1054 	inc_nlink(inode);
1055 	inode->i_ctime = current_time(inode);
1056 	mark_inode_dirty(inode);
1057 	dir->i_ctime = dir->i_mtime = current_time(dir);
1058 	mark_inode_dirty(dir);
1059 	ihold(inode);
1060 	d_instantiate(dentry, inode);
1061 
1062 	return 0;
1063 }
1064 
1065 /* Anybody can rename anything with this: the permission checks are left to the
1066  * higher-level routines.
1067  */
1068 static int udf_rename(struct inode *old_dir, struct dentry *old_dentry,
1069 		      struct inode *new_dir, struct dentry *new_dentry,
1070 		      unsigned int flags)
1071 {
1072 	struct inode *old_inode = d_inode(old_dentry);
1073 	struct inode *new_inode = d_inode(new_dentry);
1074 	struct udf_fileident_bh ofibh, nfibh;
1075 	struct fileIdentDesc *ofi = NULL, *nfi = NULL, *dir_fi = NULL;
1076 	struct fileIdentDesc ocfi, ncfi;
1077 	struct buffer_head *dir_bh = NULL;
1078 	int retval = -ENOENT;
1079 	struct kernel_lb_addr tloc;
1080 	struct udf_inode_info *old_iinfo = UDF_I(old_inode);
1081 
1082 	if (flags & ~RENAME_NOREPLACE)
1083 		return -EINVAL;
1084 
1085 	ofi = udf_find_entry(old_dir, &old_dentry->d_name, &ofibh, &ocfi);
1086 	if (IS_ERR(ofi)) {
1087 		retval = PTR_ERR(ofi);
1088 		goto end_rename;
1089 	}
1090 
1091 	if (ofibh.sbh != ofibh.ebh)
1092 		brelse(ofibh.ebh);
1093 
1094 	brelse(ofibh.sbh);
1095 	tloc = lelb_to_cpu(ocfi.icb.extLocation);
1096 	if (!ofi || udf_get_lb_pblock(old_dir->i_sb, &tloc, 0)
1097 	    != old_inode->i_ino)
1098 		goto end_rename;
1099 
1100 	nfi = udf_find_entry(new_dir, &new_dentry->d_name, &nfibh, &ncfi);
1101 	if (IS_ERR(nfi)) {
1102 		retval = PTR_ERR(nfi);
1103 		goto end_rename;
1104 	}
1105 	if (nfi && !new_inode) {
1106 		if (nfibh.sbh != nfibh.ebh)
1107 			brelse(nfibh.ebh);
1108 		brelse(nfibh.sbh);
1109 		nfi = NULL;
1110 	}
1111 	if (S_ISDIR(old_inode->i_mode)) {
1112 		int offset = udf_ext0_offset(old_inode);
1113 
1114 		if (new_inode) {
1115 			retval = -ENOTEMPTY;
1116 			if (!empty_dir(new_inode))
1117 				goto end_rename;
1118 		}
1119 		retval = -EIO;
1120 		if (old_iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1121 			dir_fi = udf_get_fileident(
1122 					old_iinfo->i_data -
1123 					  (old_iinfo->i_efe ?
1124 					   sizeof(struct extendedFileEntry) :
1125 					   sizeof(struct fileEntry)),
1126 					old_inode->i_sb->s_blocksize, &offset);
1127 		} else {
1128 			dir_bh = udf_bread(old_inode, 0, 0, &retval);
1129 			if (!dir_bh)
1130 				goto end_rename;
1131 			dir_fi = udf_get_fileident(dir_bh->b_data,
1132 					old_inode->i_sb->s_blocksize, &offset);
1133 		}
1134 		if (!dir_fi)
1135 			goto end_rename;
1136 		tloc = lelb_to_cpu(dir_fi->icb.extLocation);
1137 		if (udf_get_lb_pblock(old_inode->i_sb, &tloc, 0) !=
1138 				old_dir->i_ino)
1139 			goto end_rename;
1140 	}
1141 	if (!nfi) {
1142 		nfi = udf_add_entry(new_dir, new_dentry, &nfibh, &ncfi,
1143 				    &retval);
1144 		if (!nfi)
1145 			goto end_rename;
1146 	}
1147 
1148 	/*
1149 	 * Like most other Unix systems, set the ctime for inodes on a
1150 	 * rename.
1151 	 */
1152 	old_inode->i_ctime = current_time(old_inode);
1153 	mark_inode_dirty(old_inode);
1154 
1155 	/*
1156 	 * ok, that's it
1157 	 */
1158 	ncfi.fileVersionNum = ocfi.fileVersionNum;
1159 	ncfi.fileCharacteristics = ocfi.fileCharacteristics;
1160 	memcpy(&(ncfi.icb), &(ocfi.icb), sizeof(ocfi.icb));
1161 	udf_write_fi(new_dir, &ncfi, nfi, &nfibh, NULL, NULL);
1162 
1163 	/* The old fid may have moved - find it again */
1164 	ofi = udf_find_entry(old_dir, &old_dentry->d_name, &ofibh, &ocfi);
1165 	udf_delete_entry(old_dir, ofi, &ofibh, &ocfi);
1166 
1167 	if (new_inode) {
1168 		new_inode->i_ctime = current_time(new_inode);
1169 		inode_dec_link_count(new_inode);
1170 	}
1171 	old_dir->i_ctime = old_dir->i_mtime = current_time(old_dir);
1172 	new_dir->i_ctime = new_dir->i_mtime = current_time(new_dir);
1173 	mark_inode_dirty(old_dir);
1174 	mark_inode_dirty(new_dir);
1175 
1176 	if (dir_fi) {
1177 		dir_fi->icb.extLocation = cpu_to_lelb(UDF_I(new_dir)->i_location);
1178 		udf_update_tag((char *)dir_fi, udf_dir_entry_len(dir_fi));
1179 		if (old_iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1180 			mark_inode_dirty(old_inode);
1181 		else
1182 			mark_buffer_dirty_inode(dir_bh, old_inode);
1183 
1184 		inode_dec_link_count(old_dir);
1185 		if (new_inode)
1186 			inode_dec_link_count(new_inode);
1187 		else {
1188 			inc_nlink(new_dir);
1189 			mark_inode_dirty(new_dir);
1190 		}
1191 	}
1192 
1193 	if (ofi) {
1194 		if (ofibh.sbh != ofibh.ebh)
1195 			brelse(ofibh.ebh);
1196 		brelse(ofibh.sbh);
1197 	}
1198 
1199 	retval = 0;
1200 
1201 end_rename:
1202 	brelse(dir_bh);
1203 	if (nfi) {
1204 		if (nfibh.sbh != nfibh.ebh)
1205 			brelse(nfibh.ebh);
1206 		brelse(nfibh.sbh);
1207 	}
1208 
1209 	return retval;
1210 }
1211 
1212 static struct dentry *udf_get_parent(struct dentry *child)
1213 {
1214 	struct kernel_lb_addr tloc;
1215 	struct inode *inode = NULL;
1216 	struct qstr dotdot = QSTR_INIT("..", 2);
1217 	struct fileIdentDesc cfi;
1218 	struct udf_fileident_bh fibh;
1219 
1220 	if (!udf_find_entry(d_inode(child), &dotdot, &fibh, &cfi))
1221 		return ERR_PTR(-EACCES);
1222 
1223 	if (fibh.sbh != fibh.ebh)
1224 		brelse(fibh.ebh);
1225 	brelse(fibh.sbh);
1226 
1227 	tloc = lelb_to_cpu(cfi.icb.extLocation);
1228 	inode = udf_iget(child->d_sb, &tloc);
1229 	if (IS_ERR(inode))
1230 		return ERR_CAST(inode);
1231 
1232 	return d_obtain_alias(inode);
1233 }
1234 
1235 
1236 static struct dentry *udf_nfs_get_inode(struct super_block *sb, u32 block,
1237 					u16 partref, __u32 generation)
1238 {
1239 	struct inode *inode;
1240 	struct kernel_lb_addr loc;
1241 
1242 	if (block == 0)
1243 		return ERR_PTR(-ESTALE);
1244 
1245 	loc.logicalBlockNum = block;
1246 	loc.partitionReferenceNum = partref;
1247 	inode = udf_iget(sb, &loc);
1248 
1249 	if (IS_ERR(inode))
1250 		return ERR_CAST(inode);
1251 
1252 	if (generation && inode->i_generation != generation) {
1253 		iput(inode);
1254 		return ERR_PTR(-ESTALE);
1255 	}
1256 	return d_obtain_alias(inode);
1257 }
1258 
1259 static struct dentry *udf_fh_to_dentry(struct super_block *sb,
1260 				       struct fid *fid, int fh_len, int fh_type)
1261 {
1262 	if (fh_len < 3 ||
1263 	    (fh_type != FILEID_UDF_WITH_PARENT &&
1264 	     fh_type != FILEID_UDF_WITHOUT_PARENT))
1265 		return NULL;
1266 
1267 	return udf_nfs_get_inode(sb, fid->udf.block, fid->udf.partref,
1268 			fid->udf.generation);
1269 }
1270 
1271 static struct dentry *udf_fh_to_parent(struct super_block *sb,
1272 				       struct fid *fid, int fh_len, int fh_type)
1273 {
1274 	if (fh_len < 5 || fh_type != FILEID_UDF_WITH_PARENT)
1275 		return NULL;
1276 
1277 	return udf_nfs_get_inode(sb, fid->udf.parent_block,
1278 				 fid->udf.parent_partref,
1279 				 fid->udf.parent_generation);
1280 }
1281 static int udf_encode_fh(struct inode *inode, __u32 *fh, int *lenp,
1282 			 struct inode *parent)
1283 {
1284 	int len = *lenp;
1285 	struct kernel_lb_addr location = UDF_I(inode)->i_location;
1286 	struct fid *fid = (struct fid *)fh;
1287 	int type = FILEID_UDF_WITHOUT_PARENT;
1288 
1289 	if (parent && (len < 5)) {
1290 		*lenp = 5;
1291 		return FILEID_INVALID;
1292 	} else if (len < 3) {
1293 		*lenp = 3;
1294 		return FILEID_INVALID;
1295 	}
1296 
1297 	*lenp = 3;
1298 	fid->udf.block = location.logicalBlockNum;
1299 	fid->udf.partref = location.partitionReferenceNum;
1300 	fid->udf.parent_partref = 0;
1301 	fid->udf.generation = inode->i_generation;
1302 
1303 	if (parent) {
1304 		location = UDF_I(parent)->i_location;
1305 		fid->udf.parent_block = location.logicalBlockNum;
1306 		fid->udf.parent_partref = location.partitionReferenceNum;
1307 		fid->udf.parent_generation = inode->i_generation;
1308 		*lenp = 5;
1309 		type = FILEID_UDF_WITH_PARENT;
1310 	}
1311 
1312 	return type;
1313 }
1314 
1315 const struct export_operations udf_export_ops = {
1316 	.encode_fh	= udf_encode_fh,
1317 	.fh_to_dentry   = udf_fh_to_dentry,
1318 	.fh_to_parent   = udf_fh_to_parent,
1319 	.get_parent     = udf_get_parent,
1320 };
1321 
1322 const struct inode_operations udf_dir_inode_operations = {
1323 	.lookup				= udf_lookup,
1324 	.create				= udf_create,
1325 	.link				= udf_link,
1326 	.unlink				= udf_unlink,
1327 	.symlink			= udf_symlink,
1328 	.mkdir				= udf_mkdir,
1329 	.rmdir				= udf_rmdir,
1330 	.mknod				= udf_mknod,
1331 	.rename				= udf_rename,
1332 	.tmpfile			= udf_tmpfile,
1333 };
1334