xref: /linux/fs/udf/namei.c (revision 4949009eb8d40a441dcddcd96e101e77d31cf1b2)
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/buffer_head.h>
31 #include <linux/sched.h>
32 #include <linux/crc-itu-t.h>
33 #include <linux/exportfs.h>
34 
35 static inline int udf_match(int len1, const unsigned char *name1, int len2,
36 			    const unsigned char *name2)
37 {
38 	if (len1 != len2)
39 		return 0;
40 
41 	return !memcmp(name1, name2, len1);
42 }
43 
44 int udf_write_fi(struct inode *inode, struct fileIdentDesc *cfi,
45 		 struct fileIdentDesc *sfi, struct udf_fileident_bh *fibh,
46 		 uint8_t *impuse, uint8_t *fileident)
47 {
48 	uint16_t crclen = fibh->eoffset - fibh->soffset - sizeof(struct tag);
49 	uint16_t crc;
50 	int offset;
51 	uint16_t liu = le16_to_cpu(cfi->lengthOfImpUse);
52 	uint8_t lfi = cfi->lengthFileIdent;
53 	int padlen = fibh->eoffset - fibh->soffset - liu - lfi -
54 		sizeof(struct fileIdentDesc);
55 	int adinicb = 0;
56 
57 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
58 		adinicb = 1;
59 
60 	offset = fibh->soffset + sizeof(struct fileIdentDesc);
61 
62 	if (impuse) {
63 		if (adinicb || (offset + liu < 0)) {
64 			memcpy((uint8_t *)sfi->impUse, impuse, liu);
65 		} else if (offset >= 0) {
66 			memcpy(fibh->ebh->b_data + offset, impuse, liu);
67 		} else {
68 			memcpy((uint8_t *)sfi->impUse, impuse, -offset);
69 			memcpy(fibh->ebh->b_data, impuse - offset,
70 				liu + offset);
71 		}
72 	}
73 
74 	offset += liu;
75 
76 	if (fileident) {
77 		if (adinicb || (offset + lfi < 0)) {
78 			memcpy((uint8_t *)sfi->fileIdent + liu, fileident, lfi);
79 		} else if (offset >= 0) {
80 			memcpy(fibh->ebh->b_data + offset, fileident, lfi);
81 		} else {
82 			memcpy((uint8_t *)sfi->fileIdent + liu, fileident,
83 				-offset);
84 			memcpy(fibh->ebh->b_data, fileident - offset,
85 				lfi + offset);
86 		}
87 	}
88 
89 	offset += lfi;
90 
91 	if (adinicb || (offset + padlen < 0)) {
92 		memset((uint8_t *)sfi->padding + liu + lfi, 0x00, padlen);
93 	} else if (offset >= 0) {
94 		memset(fibh->ebh->b_data + offset, 0x00, padlen);
95 	} else {
96 		memset((uint8_t *)sfi->padding + liu + lfi, 0x00, -offset);
97 		memset(fibh->ebh->b_data, 0x00, padlen + offset);
98 	}
99 
100 	crc = crc_itu_t(0, (uint8_t *)cfi + sizeof(struct tag),
101 		      sizeof(struct fileIdentDesc) - sizeof(struct tag));
102 
103 	if (fibh->sbh == fibh->ebh) {
104 		crc = crc_itu_t(crc, (uint8_t *)sfi->impUse,
105 			      crclen + sizeof(struct tag) -
106 			      sizeof(struct fileIdentDesc));
107 	} else if (sizeof(struct fileIdentDesc) >= -fibh->soffset) {
108 		crc = crc_itu_t(crc, fibh->ebh->b_data +
109 					sizeof(struct fileIdentDesc) +
110 					fibh->soffset,
111 			      crclen + sizeof(struct tag) -
112 					sizeof(struct fileIdentDesc));
113 	} else {
114 		crc = crc_itu_t(crc, (uint8_t *)sfi->impUse,
115 			      -fibh->soffset - sizeof(struct fileIdentDesc));
116 		crc = crc_itu_t(crc, fibh->ebh->b_data, fibh->eoffset);
117 	}
118 
119 	cfi->descTag.descCRC = cpu_to_le16(crc);
120 	cfi->descTag.descCRCLength = cpu_to_le16(crclen);
121 	cfi->descTag.tagChecksum = udf_tag_checksum(&cfi->descTag);
122 
123 	if (adinicb || (sizeof(struct fileIdentDesc) <= -fibh->soffset)) {
124 		memcpy((uint8_t *)sfi, (uint8_t *)cfi,
125 			sizeof(struct fileIdentDesc));
126 	} else {
127 		memcpy((uint8_t *)sfi, (uint8_t *)cfi, -fibh->soffset);
128 		memcpy(fibh->ebh->b_data, (uint8_t *)cfi - fibh->soffset,
129 		       sizeof(struct fileIdentDesc) + fibh->soffset);
130 	}
131 
132 	if (adinicb) {
133 		mark_inode_dirty(inode);
134 	} else {
135 		if (fibh->sbh != fibh->ebh)
136 			mark_buffer_dirty_inode(fibh->ebh, inode);
137 		mark_buffer_dirty_inode(fibh->sbh, inode);
138 	}
139 	return 0;
140 }
141 
142 static struct fileIdentDesc *udf_find_entry(struct inode *dir,
143 					    const struct qstr *child,
144 					    struct udf_fileident_bh *fibh,
145 					    struct fileIdentDesc *cfi)
146 {
147 	struct fileIdentDesc *fi = NULL;
148 	loff_t f_pos;
149 	int block, flen;
150 	unsigned char *fname = NULL;
151 	unsigned char *nameptr;
152 	uint8_t lfi;
153 	uint16_t liu;
154 	loff_t size;
155 	struct kernel_lb_addr eloc;
156 	uint32_t elen;
157 	sector_t offset;
158 	struct extent_position epos = {};
159 	struct udf_inode_info *dinfo = UDF_I(dir);
160 	int isdotdot = child->len == 2 &&
161 		child->name[0] == '.' && child->name[1] == '.';
162 	struct super_block *sb = dir->i_sb;
163 
164 	size = udf_ext0_offset(dir) + dir->i_size;
165 	f_pos = udf_ext0_offset(dir);
166 
167 	fibh->sbh = fibh->ebh = NULL;
168 	fibh->soffset = fibh->eoffset = f_pos & (sb->s_blocksize - 1);
169 	if (dinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
170 		if (inode_bmap(dir, f_pos >> sb->s_blocksize_bits, &epos,
171 		    &eloc, &elen, &offset) != (EXT_RECORDED_ALLOCATED >> 30))
172 			goto out_err;
173 		block = udf_get_lb_pblock(sb, &eloc, offset);
174 		if ((++offset << sb->s_blocksize_bits) < elen) {
175 			if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
176 				epos.offset -= sizeof(struct short_ad);
177 			else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
178 				epos.offset -= sizeof(struct long_ad);
179 		} else
180 			offset = 0;
181 
182 		fibh->sbh = fibh->ebh = udf_tread(sb, block);
183 		if (!fibh->sbh)
184 			goto out_err;
185 	}
186 
187 	fname = kmalloc(UDF_NAME_LEN, GFP_NOFS);
188 	if (!fname)
189 		goto out_err;
190 
191 	while (f_pos < size) {
192 		fi = udf_fileident_read(dir, &f_pos, fibh, cfi, &epos, &eloc,
193 					&elen, &offset);
194 		if (!fi)
195 			goto out_err;
196 
197 		liu = le16_to_cpu(cfi->lengthOfImpUse);
198 		lfi = cfi->lengthFileIdent;
199 
200 		if (fibh->sbh == fibh->ebh) {
201 			nameptr = fi->fileIdent + liu;
202 		} else {
203 			int poffset;	/* Unpaded ending offset */
204 
205 			poffset = fibh->soffset + sizeof(struct fileIdentDesc) +
206 					liu + lfi;
207 
208 			if (poffset >= lfi)
209 				nameptr = (uint8_t *)(fibh->ebh->b_data +
210 						      poffset - lfi);
211 			else {
212 				nameptr = fname;
213 				memcpy(nameptr, fi->fileIdent + liu,
214 					lfi - poffset);
215 				memcpy(nameptr + lfi - poffset,
216 					fibh->ebh->b_data, poffset);
217 			}
218 		}
219 
220 		if ((cfi->fileCharacteristics & FID_FILE_CHAR_DELETED) != 0) {
221 			if (!UDF_QUERY_FLAG(sb, UDF_FLAG_UNDELETE))
222 				continue;
223 		}
224 
225 		if ((cfi->fileCharacteristics & FID_FILE_CHAR_HIDDEN) != 0) {
226 			if (!UDF_QUERY_FLAG(sb, UDF_FLAG_UNHIDE))
227 				continue;
228 		}
229 
230 		if ((cfi->fileCharacteristics & FID_FILE_CHAR_PARENT) &&
231 		    isdotdot)
232 			goto out_ok;
233 
234 		if (!lfi)
235 			continue;
236 
237 		flen = udf_get_filename(sb, nameptr, lfi, fname, UDF_NAME_LEN);
238 		if (flen && udf_match(flen, fname, child->len, child->name))
239 			goto out_ok;
240 	}
241 
242 out_err:
243 	fi = NULL;
244 	if (fibh->sbh != fibh->ebh)
245 		brelse(fibh->ebh);
246 	brelse(fibh->sbh);
247 out_ok:
248 	brelse(epos.bh);
249 	kfree(fname);
250 
251 	return fi;
252 }
253 
254 static struct dentry *udf_lookup(struct inode *dir, struct dentry *dentry,
255 				 unsigned int flags)
256 {
257 	struct inode *inode = NULL;
258 	struct fileIdentDesc cfi;
259 	struct udf_fileident_bh fibh;
260 
261 	if (dentry->d_name.len > UDF_NAME_LEN - 2)
262 		return ERR_PTR(-ENAMETOOLONG);
263 
264 #ifdef UDF_RECOVERY
265 	/* temporary shorthand for specifying files by inode number */
266 	if (!strncmp(dentry->d_name.name, ".B=", 3)) {
267 		struct kernel_lb_addr lb = {
268 			.logicalBlockNum = 0,
269 			.partitionReferenceNum =
270 				simple_strtoul(dentry->d_name.name + 3,
271 						NULL, 0),
272 		};
273 		inode = udf_iget(dir->i_sb, lb);
274 		if (IS_ERR(inode))
275 			return inode;
276 	} else
277 #endif /* UDF_RECOVERY */
278 
279 	if (udf_find_entry(dir, &dentry->d_name, &fibh, &cfi)) {
280 		struct kernel_lb_addr loc;
281 
282 		if (fibh.sbh != fibh.ebh)
283 			brelse(fibh.ebh);
284 		brelse(fibh.sbh);
285 
286 		loc = lelb_to_cpu(cfi.icb.extLocation);
287 		inode = udf_iget(dir->i_sb, &loc);
288 		if (IS_ERR(inode))
289 			return ERR_CAST(inode);
290 	}
291 
292 	return d_splice_alias(inode, dentry);
293 }
294 
295 static struct fileIdentDesc *udf_add_entry(struct inode *dir,
296 					   struct dentry *dentry,
297 					   struct udf_fileident_bh *fibh,
298 					   struct fileIdentDesc *cfi, int *err)
299 {
300 	struct super_block *sb = dir->i_sb;
301 	struct fileIdentDesc *fi = NULL;
302 	unsigned char *name = NULL;
303 	int namelen;
304 	loff_t f_pos;
305 	loff_t size = udf_ext0_offset(dir) + dir->i_size;
306 	int nfidlen;
307 	uint8_t lfi;
308 	uint16_t liu;
309 	int block;
310 	struct kernel_lb_addr eloc;
311 	uint32_t elen = 0;
312 	sector_t offset;
313 	struct extent_position epos = {};
314 	struct udf_inode_info *dinfo;
315 
316 	fibh->sbh = fibh->ebh = NULL;
317 	name = kmalloc(UDF_NAME_LEN, GFP_NOFS);
318 	if (!name) {
319 		*err = -ENOMEM;
320 		goto out_err;
321 	}
322 
323 	if (dentry) {
324 		if (!dentry->d_name.len) {
325 			*err = -EINVAL;
326 			goto out_err;
327 		}
328 		namelen = udf_put_filename(sb, dentry->d_name.name, name,
329 						 dentry->d_name.len);
330 		if (!namelen) {
331 			*err = -ENAMETOOLONG;
332 			goto out_err;
333 		}
334 	} else {
335 		namelen = 0;
336 	}
337 
338 	nfidlen = (sizeof(struct fileIdentDesc) + namelen + 3) & ~3;
339 
340 	f_pos = udf_ext0_offset(dir);
341 
342 	fibh->soffset = fibh->eoffset = f_pos & (dir->i_sb->s_blocksize - 1);
343 	dinfo = UDF_I(dir);
344 	if (dinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
345 		if (inode_bmap(dir, f_pos >> dir->i_sb->s_blocksize_bits, &epos,
346 		    &eloc, &elen, &offset) != (EXT_RECORDED_ALLOCATED >> 30)) {
347 			block = udf_get_lb_pblock(dir->i_sb,
348 					&dinfo->i_location, 0);
349 			fibh->soffset = fibh->eoffset = sb->s_blocksize;
350 			goto add;
351 		}
352 		block = udf_get_lb_pblock(dir->i_sb, &eloc, offset);
353 		if ((++offset << dir->i_sb->s_blocksize_bits) < elen) {
354 			if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
355 				epos.offset -= sizeof(struct short_ad);
356 			else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
357 				epos.offset -= sizeof(struct long_ad);
358 		} else
359 			offset = 0;
360 
361 		fibh->sbh = fibh->ebh = udf_tread(dir->i_sb, block);
362 		if (!fibh->sbh) {
363 			*err = -EIO;
364 			goto out_err;
365 		}
366 
367 		block = dinfo->i_location.logicalBlockNum;
368 	}
369 
370 	while (f_pos < size) {
371 		fi = udf_fileident_read(dir, &f_pos, fibh, cfi, &epos, &eloc,
372 					&elen, &offset);
373 
374 		if (!fi) {
375 			*err = -EIO;
376 			goto out_err;
377 		}
378 
379 		liu = le16_to_cpu(cfi->lengthOfImpUse);
380 		lfi = cfi->lengthFileIdent;
381 
382 		if ((cfi->fileCharacteristics & FID_FILE_CHAR_DELETED) != 0) {
383 			if (((sizeof(struct fileIdentDesc) +
384 					liu + lfi + 3) & ~3) == nfidlen) {
385 				cfi->descTag.tagSerialNum = cpu_to_le16(1);
386 				cfi->fileVersionNum = cpu_to_le16(1);
387 				cfi->fileCharacteristics = 0;
388 				cfi->lengthFileIdent = namelen;
389 				cfi->lengthOfImpUse = cpu_to_le16(0);
390 				if (!udf_write_fi(dir, cfi, fi, fibh, NULL,
391 						  name))
392 					goto out_ok;
393 				else {
394 					*err = -EIO;
395 					goto out_err;
396 				}
397 			}
398 		}
399 	}
400 
401 add:
402 	f_pos += nfidlen;
403 
404 	if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB &&
405 	    sb->s_blocksize - fibh->eoffset < nfidlen) {
406 		brelse(epos.bh);
407 		epos.bh = NULL;
408 		fibh->soffset -= udf_ext0_offset(dir);
409 		fibh->eoffset -= udf_ext0_offset(dir);
410 		f_pos -= udf_ext0_offset(dir);
411 		if (fibh->sbh != fibh->ebh)
412 			brelse(fibh->ebh);
413 		brelse(fibh->sbh);
414 		fibh->sbh = fibh->ebh =
415 				udf_expand_dir_adinicb(dir, &block, err);
416 		if (!fibh->sbh)
417 			goto out_err;
418 		epos.block = dinfo->i_location;
419 		epos.offset = udf_file_entry_alloc_offset(dir);
420 		/* Load extent udf_expand_dir_adinicb() has created */
421 		udf_current_aext(dir, &epos, &eloc, &elen, 1);
422 	}
423 
424 	/* Entry fits into current block? */
425 	if (sb->s_blocksize - fibh->eoffset >= nfidlen) {
426 		fibh->soffset = fibh->eoffset;
427 		fibh->eoffset += nfidlen;
428 		if (fibh->sbh != fibh->ebh) {
429 			brelse(fibh->sbh);
430 			fibh->sbh = fibh->ebh;
431 		}
432 
433 		if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
434 			block = dinfo->i_location.logicalBlockNum;
435 			fi = (struct fileIdentDesc *)
436 					(dinfo->i_ext.i_data +
437 					 fibh->soffset -
438 					 udf_ext0_offset(dir) +
439 					 dinfo->i_lenEAttr);
440 		} else {
441 			block = eloc.logicalBlockNum +
442 					((elen - 1) >>
443 						dir->i_sb->s_blocksize_bits);
444 			fi = (struct fileIdentDesc *)
445 				(fibh->sbh->b_data + fibh->soffset);
446 		}
447 	} else {
448 		/* Round up last extent in the file */
449 		elen = (elen + sb->s_blocksize - 1) & ~(sb->s_blocksize - 1);
450 		if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
451 			epos.offset -= sizeof(struct short_ad);
452 		else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
453 			epos.offset -= sizeof(struct long_ad);
454 		udf_write_aext(dir, &epos, &eloc, elen, 1);
455 		dinfo->i_lenExtents = (dinfo->i_lenExtents + sb->s_blocksize
456 					- 1) & ~(sb->s_blocksize - 1);
457 
458 		fibh->soffset = fibh->eoffset - sb->s_blocksize;
459 		fibh->eoffset += nfidlen - sb->s_blocksize;
460 		if (fibh->sbh != fibh->ebh) {
461 			brelse(fibh->sbh);
462 			fibh->sbh = fibh->ebh;
463 		}
464 
465 		block = eloc.logicalBlockNum + ((elen - 1) >>
466 						dir->i_sb->s_blocksize_bits);
467 		fibh->ebh = udf_bread(dir,
468 				f_pos >> dir->i_sb->s_blocksize_bits, 1, err);
469 		if (!fibh->ebh)
470 			goto out_err;
471 		/* Extents could have been merged, invalidate our position */
472 		brelse(epos.bh);
473 		epos.bh = NULL;
474 		epos.block = dinfo->i_location;
475 		epos.offset = udf_file_entry_alloc_offset(dir);
476 
477 		if (!fibh->soffset) {
478 			/* Find the freshly allocated block */
479 			while (udf_next_aext(dir, &epos, &eloc, &elen, 1) ==
480 				(EXT_RECORDED_ALLOCATED >> 30))
481 				;
482 			block = eloc.logicalBlockNum + ((elen - 1) >>
483 					dir->i_sb->s_blocksize_bits);
484 			brelse(fibh->sbh);
485 			fibh->sbh = fibh->ebh;
486 			fi = (struct fileIdentDesc *)(fibh->sbh->b_data);
487 		} else {
488 			fi = (struct fileIdentDesc *)
489 				(fibh->sbh->b_data + sb->s_blocksize +
490 					fibh->soffset);
491 		}
492 	}
493 
494 	memset(cfi, 0, sizeof(struct fileIdentDesc));
495 	if (UDF_SB(sb)->s_udfrev >= 0x0200)
496 		udf_new_tag((char *)cfi, TAG_IDENT_FID, 3, 1, block,
497 			    sizeof(struct tag));
498 	else
499 		udf_new_tag((char *)cfi, TAG_IDENT_FID, 2, 1, block,
500 			    sizeof(struct tag));
501 	cfi->fileVersionNum = cpu_to_le16(1);
502 	cfi->lengthFileIdent = namelen;
503 	cfi->lengthOfImpUse = cpu_to_le16(0);
504 	if (!udf_write_fi(dir, cfi, fi, fibh, NULL, name)) {
505 		dir->i_size += nfidlen;
506 		if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
507 			dinfo->i_lenAlloc += nfidlen;
508 		else {
509 			/* Find the last extent and truncate it to proper size */
510 			while (udf_next_aext(dir, &epos, &eloc, &elen, 1) ==
511 				(EXT_RECORDED_ALLOCATED >> 30))
512 				;
513 			elen -= dinfo->i_lenExtents - dir->i_size;
514 			if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
515 				epos.offset -= sizeof(struct short_ad);
516 			else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
517 				epos.offset -= sizeof(struct long_ad);
518 			udf_write_aext(dir, &epos, &eloc, elen, 1);
519 			dinfo->i_lenExtents = dir->i_size;
520 		}
521 
522 		mark_inode_dirty(dir);
523 		goto out_ok;
524 	} else {
525 		*err = -EIO;
526 		goto out_err;
527 	}
528 
529 out_err:
530 	fi = NULL;
531 	if (fibh->sbh != fibh->ebh)
532 		brelse(fibh->ebh);
533 	brelse(fibh->sbh);
534 out_ok:
535 	brelse(epos.bh);
536 	kfree(name);
537 	return fi;
538 }
539 
540 static int udf_delete_entry(struct inode *inode, struct fileIdentDesc *fi,
541 			    struct udf_fileident_bh *fibh,
542 			    struct fileIdentDesc *cfi)
543 {
544 	cfi->fileCharacteristics |= FID_FILE_CHAR_DELETED;
545 
546 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT))
547 		memset(&(cfi->icb), 0x00, sizeof(struct long_ad));
548 
549 	return udf_write_fi(inode, cfi, fi, fibh, NULL, NULL);
550 }
551 
552 static int udf_add_nondir(struct dentry *dentry, struct inode *inode)
553 {
554 	struct udf_inode_info *iinfo = UDF_I(inode);
555 	struct inode *dir = dentry->d_parent->d_inode;
556 	struct udf_fileident_bh fibh;
557 	struct fileIdentDesc cfi, *fi;
558 	int err;
559 
560 	fi = udf_add_entry(dir, dentry, &fibh, &cfi, &err);
561 	if (unlikely(!fi)) {
562 		inode_dec_link_count(inode);
563 		unlock_new_inode(inode);
564 		iput(inode);
565 		return err;
566 	}
567 	cfi.icb.extLength = cpu_to_le32(inode->i_sb->s_blocksize);
568 	cfi.icb.extLocation = cpu_to_lelb(iinfo->i_location);
569 	*(__le32 *)((struct allocDescImpUse *)cfi.icb.impUse)->impUse =
570 		cpu_to_le32(iinfo->i_unique & 0x00000000FFFFFFFFUL);
571 	udf_write_fi(dir, &cfi, fi, &fibh, NULL, NULL);
572 	if (UDF_I(dir)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
573 		mark_inode_dirty(dir);
574 	if (fibh.sbh != fibh.ebh)
575 		brelse(fibh.ebh);
576 	brelse(fibh.sbh);
577 	unlock_new_inode(inode);
578 	d_instantiate(dentry, inode);
579 
580 	return 0;
581 }
582 
583 static int udf_create(struct inode *dir, struct dentry *dentry, umode_t mode,
584 		      bool excl)
585 {
586 	struct inode *inode = udf_new_inode(dir, mode);
587 
588 	if (IS_ERR(inode))
589 		return PTR_ERR(inode);
590 
591 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
592 		inode->i_data.a_ops = &udf_adinicb_aops;
593 	else
594 		inode->i_data.a_ops = &udf_aops;
595 	inode->i_op = &udf_file_inode_operations;
596 	inode->i_fop = &udf_file_operations;
597 	mark_inode_dirty(inode);
598 
599 	return udf_add_nondir(dentry, inode);
600 }
601 
602 static int udf_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
603 {
604 	struct inode *inode = udf_new_inode(dir, mode);
605 
606 	if (IS_ERR(inode))
607 		return PTR_ERR(inode);
608 
609 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
610 		inode->i_data.a_ops = &udf_adinicb_aops;
611 	else
612 		inode->i_data.a_ops = &udf_aops;
613 	inode->i_op = &udf_file_inode_operations;
614 	inode->i_fop = &udf_file_operations;
615 	mark_inode_dirty(inode);
616 	d_tmpfile(dentry, inode);
617 	unlock_new_inode(inode);
618 	return 0;
619 }
620 
621 static int udf_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
622 		     dev_t rdev)
623 {
624 	struct inode *inode;
625 
626 	if (!old_valid_dev(rdev))
627 		return -EINVAL;
628 
629 	inode = udf_new_inode(dir, mode);
630 	if (IS_ERR(inode))
631 		return PTR_ERR(inode);
632 
633 	init_special_inode(inode, mode, rdev);
634 	return udf_add_nondir(dentry, inode);
635 }
636 
637 static int udf_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
638 {
639 	struct inode *inode;
640 	struct udf_fileident_bh fibh;
641 	struct fileIdentDesc cfi, *fi;
642 	int err;
643 	struct udf_inode_info *dinfo = UDF_I(dir);
644 	struct udf_inode_info *iinfo;
645 
646 	inode = udf_new_inode(dir, S_IFDIR | mode);
647 	if (IS_ERR(inode))
648 		return PTR_ERR(inode);
649 
650 	iinfo = UDF_I(inode);
651 	inode->i_op = &udf_dir_inode_operations;
652 	inode->i_fop = &udf_dir_operations;
653 	fi = udf_add_entry(inode, NULL, &fibh, &cfi, &err);
654 	if (!fi) {
655 		inode_dec_link_count(inode);
656 		unlock_new_inode(inode);
657 		iput(inode);
658 		goto out;
659 	}
660 	set_nlink(inode, 2);
661 	cfi.icb.extLength = cpu_to_le32(inode->i_sb->s_blocksize);
662 	cfi.icb.extLocation = cpu_to_lelb(dinfo->i_location);
663 	*(__le32 *)((struct allocDescImpUse *)cfi.icb.impUse)->impUse =
664 		cpu_to_le32(dinfo->i_unique & 0x00000000FFFFFFFFUL);
665 	cfi.fileCharacteristics =
666 			FID_FILE_CHAR_DIRECTORY | FID_FILE_CHAR_PARENT;
667 	udf_write_fi(inode, &cfi, fi, &fibh, NULL, NULL);
668 	brelse(fibh.sbh);
669 	mark_inode_dirty(inode);
670 
671 	fi = udf_add_entry(dir, dentry, &fibh, &cfi, &err);
672 	if (!fi) {
673 		clear_nlink(inode);
674 		mark_inode_dirty(inode);
675 		unlock_new_inode(inode);
676 		iput(inode);
677 		goto out;
678 	}
679 	cfi.icb.extLength = cpu_to_le32(inode->i_sb->s_blocksize);
680 	cfi.icb.extLocation = cpu_to_lelb(iinfo->i_location);
681 	*(__le32 *)((struct allocDescImpUse *)cfi.icb.impUse)->impUse =
682 		cpu_to_le32(iinfo->i_unique & 0x00000000FFFFFFFFUL);
683 	cfi.fileCharacteristics |= FID_FILE_CHAR_DIRECTORY;
684 	udf_write_fi(dir, &cfi, fi, &fibh, NULL, NULL);
685 	inc_nlink(dir);
686 	mark_inode_dirty(dir);
687 	unlock_new_inode(inode);
688 	d_instantiate(dentry, inode);
689 	if (fibh.sbh != fibh.ebh)
690 		brelse(fibh.ebh);
691 	brelse(fibh.sbh);
692 	err = 0;
693 
694 out:
695 	return err;
696 }
697 
698 static int empty_dir(struct inode *dir)
699 {
700 	struct fileIdentDesc *fi, cfi;
701 	struct udf_fileident_bh fibh;
702 	loff_t f_pos;
703 	loff_t size = udf_ext0_offset(dir) + dir->i_size;
704 	int block;
705 	struct kernel_lb_addr eloc;
706 	uint32_t elen;
707 	sector_t offset;
708 	struct extent_position epos = {};
709 	struct udf_inode_info *dinfo = UDF_I(dir);
710 
711 	f_pos = udf_ext0_offset(dir);
712 	fibh.soffset = fibh.eoffset = f_pos & (dir->i_sb->s_blocksize - 1);
713 
714 	if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
715 		fibh.sbh = fibh.ebh = NULL;
716 	else if (inode_bmap(dir, f_pos >> dir->i_sb->s_blocksize_bits,
717 			      &epos, &eloc, &elen, &offset) ==
718 					(EXT_RECORDED_ALLOCATED >> 30)) {
719 		block = udf_get_lb_pblock(dir->i_sb, &eloc, offset);
720 		if ((++offset << dir->i_sb->s_blocksize_bits) < elen) {
721 			if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
722 				epos.offset -= sizeof(struct short_ad);
723 			else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
724 				epos.offset -= sizeof(struct long_ad);
725 		} else
726 			offset = 0;
727 
728 		fibh.sbh = fibh.ebh = udf_tread(dir->i_sb, block);
729 		if (!fibh.sbh) {
730 			brelse(epos.bh);
731 			return 0;
732 		}
733 	} else {
734 		brelse(epos.bh);
735 		return 0;
736 	}
737 
738 	while (f_pos < size) {
739 		fi = udf_fileident_read(dir, &f_pos, &fibh, &cfi, &epos, &eloc,
740 					&elen, &offset);
741 		if (!fi) {
742 			if (fibh.sbh != fibh.ebh)
743 				brelse(fibh.ebh);
744 			brelse(fibh.sbh);
745 			brelse(epos.bh);
746 			return 0;
747 		}
748 
749 		if (cfi.lengthFileIdent &&
750 		    (cfi.fileCharacteristics & FID_FILE_CHAR_DELETED) == 0) {
751 			if (fibh.sbh != fibh.ebh)
752 				brelse(fibh.ebh);
753 			brelse(fibh.sbh);
754 			brelse(epos.bh);
755 			return 0;
756 		}
757 	}
758 
759 	if (fibh.sbh != fibh.ebh)
760 		brelse(fibh.ebh);
761 	brelse(fibh.sbh);
762 	brelse(epos.bh);
763 
764 	return 1;
765 }
766 
767 static int udf_rmdir(struct inode *dir, struct dentry *dentry)
768 {
769 	int retval;
770 	struct inode *inode = dentry->d_inode;
771 	struct udf_fileident_bh fibh;
772 	struct fileIdentDesc *fi, cfi;
773 	struct kernel_lb_addr tloc;
774 
775 	retval = -ENOENT;
776 	fi = udf_find_entry(dir, &dentry->d_name, &fibh, &cfi);
777 	if (!fi)
778 		goto out;
779 
780 	retval = -EIO;
781 	tloc = lelb_to_cpu(cfi.icb.extLocation);
782 	if (udf_get_lb_pblock(dir->i_sb, &tloc, 0) != inode->i_ino)
783 		goto end_rmdir;
784 	retval = -ENOTEMPTY;
785 	if (!empty_dir(inode))
786 		goto end_rmdir;
787 	retval = udf_delete_entry(dir, fi, &fibh, &cfi);
788 	if (retval)
789 		goto end_rmdir;
790 	if (inode->i_nlink != 2)
791 		udf_warn(inode->i_sb, "empty directory has nlink != 2 (%d)\n",
792 			 inode->i_nlink);
793 	clear_nlink(inode);
794 	inode->i_size = 0;
795 	inode_dec_link_count(dir);
796 	inode->i_ctime = dir->i_ctime = dir->i_mtime =
797 						current_fs_time(dir->i_sb);
798 	mark_inode_dirty(dir);
799 
800 end_rmdir:
801 	if (fibh.sbh != fibh.ebh)
802 		brelse(fibh.ebh);
803 	brelse(fibh.sbh);
804 
805 out:
806 	return retval;
807 }
808 
809 static int udf_unlink(struct inode *dir, struct dentry *dentry)
810 {
811 	int retval;
812 	struct inode *inode = dentry->d_inode;
813 	struct udf_fileident_bh fibh;
814 	struct fileIdentDesc *fi;
815 	struct fileIdentDesc cfi;
816 	struct kernel_lb_addr tloc;
817 
818 	retval = -ENOENT;
819 	fi = udf_find_entry(dir, &dentry->d_name, &fibh, &cfi);
820 	if (!fi)
821 		goto out;
822 
823 	retval = -EIO;
824 	tloc = lelb_to_cpu(cfi.icb.extLocation);
825 	if (udf_get_lb_pblock(dir->i_sb, &tloc, 0) != inode->i_ino)
826 		goto end_unlink;
827 
828 	if (!inode->i_nlink) {
829 		udf_debug("Deleting nonexistent file (%lu), %d\n",
830 			  inode->i_ino, inode->i_nlink);
831 		set_nlink(inode, 1);
832 	}
833 	retval = udf_delete_entry(dir, fi, &fibh, &cfi);
834 	if (retval)
835 		goto end_unlink;
836 	dir->i_ctime = dir->i_mtime = current_fs_time(dir->i_sb);
837 	mark_inode_dirty(dir);
838 	inode_dec_link_count(inode);
839 	inode->i_ctime = dir->i_ctime;
840 	retval = 0;
841 
842 end_unlink:
843 	if (fibh.sbh != fibh.ebh)
844 		brelse(fibh.ebh);
845 	brelse(fibh.sbh);
846 
847 out:
848 	return retval;
849 }
850 
851 static int udf_symlink(struct inode *dir, struct dentry *dentry,
852 		       const char *symname)
853 {
854 	struct inode *inode = udf_new_inode(dir, S_IFLNK | S_IRWXUGO);
855 	struct pathComponent *pc;
856 	const char *compstart;
857 	struct extent_position epos = {};
858 	int eoffset, elen = 0;
859 	uint8_t *ea;
860 	int err;
861 	int block;
862 	unsigned char *name = NULL;
863 	int namelen;
864 	struct udf_inode_info *iinfo;
865 	struct super_block *sb = dir->i_sb;
866 
867 	if (IS_ERR(inode))
868 		return PTR_ERR(inode);
869 
870 	iinfo = UDF_I(inode);
871 	down_write(&iinfo->i_data_sem);
872 	name = kmalloc(UDF_NAME_LEN, GFP_NOFS);
873 	if (!name) {
874 		err = -ENOMEM;
875 		goto out_no_entry;
876 	}
877 
878 	inode->i_data.a_ops = &udf_symlink_aops;
879 	inode->i_op = &udf_symlink_inode_operations;
880 
881 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
882 		struct kernel_lb_addr eloc;
883 		uint32_t bsize;
884 
885 		block = udf_new_block(sb, inode,
886 				iinfo->i_location.partitionReferenceNum,
887 				iinfo->i_location.logicalBlockNum, &err);
888 		if (!block)
889 			goto out_no_entry;
890 		epos.block = iinfo->i_location;
891 		epos.offset = udf_file_entry_alloc_offset(inode);
892 		epos.bh = NULL;
893 		eloc.logicalBlockNum = block;
894 		eloc.partitionReferenceNum =
895 				iinfo->i_location.partitionReferenceNum;
896 		bsize = sb->s_blocksize;
897 		iinfo->i_lenExtents = bsize;
898 		udf_add_aext(inode, &epos, &eloc, bsize, 0);
899 		brelse(epos.bh);
900 
901 		block = udf_get_pblock(sb, block,
902 				iinfo->i_location.partitionReferenceNum,
903 				0);
904 		epos.bh = udf_tgetblk(sb, block);
905 		lock_buffer(epos.bh);
906 		memset(epos.bh->b_data, 0x00, bsize);
907 		set_buffer_uptodate(epos.bh);
908 		unlock_buffer(epos.bh);
909 		mark_buffer_dirty_inode(epos.bh, inode);
910 		ea = epos.bh->b_data + udf_ext0_offset(inode);
911 	} else
912 		ea = iinfo->i_ext.i_data + iinfo->i_lenEAttr;
913 
914 	eoffset = sb->s_blocksize - udf_ext0_offset(inode);
915 	pc = (struct pathComponent *)ea;
916 
917 	if (*symname == '/') {
918 		do {
919 			symname++;
920 		} while (*symname == '/');
921 
922 		pc->componentType = 1;
923 		pc->lengthComponentIdent = 0;
924 		pc->componentFileVersionNum = 0;
925 		elen += sizeof(struct pathComponent);
926 	}
927 
928 	err = -ENAMETOOLONG;
929 
930 	while (*symname) {
931 		if (elen + sizeof(struct pathComponent) > eoffset)
932 			goto out_no_entry;
933 
934 		pc = (struct pathComponent *)(ea + elen);
935 
936 		compstart = symname;
937 
938 		do {
939 			symname++;
940 		} while (*symname && *symname != '/');
941 
942 		pc->componentType = 5;
943 		pc->lengthComponentIdent = 0;
944 		pc->componentFileVersionNum = 0;
945 		if (compstart[0] == '.') {
946 			if ((symname - compstart) == 1)
947 				pc->componentType = 4;
948 			else if ((symname - compstart) == 2 &&
949 					compstart[1] == '.')
950 				pc->componentType = 3;
951 		}
952 
953 		if (pc->componentType == 5) {
954 			namelen = udf_put_filename(sb, compstart, name,
955 						   symname - compstart);
956 			if (!namelen)
957 				goto out_no_entry;
958 
959 			if (elen + sizeof(struct pathComponent) + namelen >
960 					eoffset)
961 				goto out_no_entry;
962 			else
963 				pc->lengthComponentIdent = namelen;
964 
965 			memcpy(pc->componentIdent, name, namelen);
966 		}
967 
968 		elen += sizeof(struct pathComponent) + pc->lengthComponentIdent;
969 
970 		if (*symname) {
971 			do {
972 				symname++;
973 			} while (*symname == '/');
974 		}
975 	}
976 
977 	brelse(epos.bh);
978 	inode->i_size = elen;
979 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
980 		iinfo->i_lenAlloc = inode->i_size;
981 	else
982 		udf_truncate_tail_extent(inode);
983 	mark_inode_dirty(inode);
984 	up_write(&iinfo->i_data_sem);
985 
986 	err = udf_add_nondir(dentry, inode);
987 out:
988 	kfree(name);
989 	return err;
990 
991 out_no_entry:
992 	up_write(&iinfo->i_data_sem);
993 	inode_dec_link_count(inode);
994 	unlock_new_inode(inode);
995 	iput(inode);
996 	goto out;
997 }
998 
999 static int udf_link(struct dentry *old_dentry, struct inode *dir,
1000 		    struct dentry *dentry)
1001 {
1002 	struct inode *inode = old_dentry->d_inode;
1003 	struct udf_fileident_bh fibh;
1004 	struct fileIdentDesc cfi, *fi;
1005 	int err;
1006 
1007 	fi = udf_add_entry(dir, dentry, &fibh, &cfi, &err);
1008 	if (!fi) {
1009 		return err;
1010 	}
1011 	cfi.icb.extLength = cpu_to_le32(inode->i_sb->s_blocksize);
1012 	cfi.icb.extLocation = cpu_to_lelb(UDF_I(inode)->i_location);
1013 	if (UDF_SB(inode->i_sb)->s_lvid_bh) {
1014 		*(__le32 *)((struct allocDescImpUse *)cfi.icb.impUse)->impUse =
1015 			cpu_to_le32(lvid_get_unique_id(inode->i_sb));
1016 	}
1017 	udf_write_fi(dir, &cfi, fi, &fibh, NULL, NULL);
1018 	if (UDF_I(dir)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1019 		mark_inode_dirty(dir);
1020 
1021 	if (fibh.sbh != fibh.ebh)
1022 		brelse(fibh.ebh);
1023 	brelse(fibh.sbh);
1024 	inc_nlink(inode);
1025 	inode->i_ctime = current_fs_time(inode->i_sb);
1026 	mark_inode_dirty(inode);
1027 	ihold(inode);
1028 	d_instantiate(dentry, inode);
1029 
1030 	return 0;
1031 }
1032 
1033 /* Anybody can rename anything with this: the permission checks are left to the
1034  * higher-level routines.
1035  */
1036 static int udf_rename(struct inode *old_dir, struct dentry *old_dentry,
1037 		      struct inode *new_dir, struct dentry *new_dentry)
1038 {
1039 	struct inode *old_inode = old_dentry->d_inode;
1040 	struct inode *new_inode = new_dentry->d_inode;
1041 	struct udf_fileident_bh ofibh, nfibh;
1042 	struct fileIdentDesc *ofi = NULL, *nfi = NULL, *dir_fi = NULL;
1043 	struct fileIdentDesc ocfi, ncfi;
1044 	struct buffer_head *dir_bh = NULL;
1045 	int retval = -ENOENT;
1046 	struct kernel_lb_addr tloc;
1047 	struct udf_inode_info *old_iinfo = UDF_I(old_inode);
1048 
1049 	ofi = udf_find_entry(old_dir, &old_dentry->d_name, &ofibh, &ocfi);
1050 	if (ofi) {
1051 		if (ofibh.sbh != ofibh.ebh)
1052 			brelse(ofibh.ebh);
1053 		brelse(ofibh.sbh);
1054 	}
1055 	tloc = lelb_to_cpu(ocfi.icb.extLocation);
1056 	if (!ofi || udf_get_lb_pblock(old_dir->i_sb, &tloc, 0)
1057 	    != old_inode->i_ino)
1058 		goto end_rename;
1059 
1060 	nfi = udf_find_entry(new_dir, &new_dentry->d_name, &nfibh, &ncfi);
1061 	if (nfi) {
1062 		if (!new_inode) {
1063 			if (nfibh.sbh != nfibh.ebh)
1064 				brelse(nfibh.ebh);
1065 			brelse(nfibh.sbh);
1066 			nfi = NULL;
1067 		}
1068 	}
1069 	if (S_ISDIR(old_inode->i_mode)) {
1070 		int offset = udf_ext0_offset(old_inode);
1071 
1072 		if (new_inode) {
1073 			retval = -ENOTEMPTY;
1074 			if (!empty_dir(new_inode))
1075 				goto end_rename;
1076 		}
1077 		retval = -EIO;
1078 		if (old_iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1079 			dir_fi = udf_get_fileident(
1080 					old_iinfo->i_ext.i_data -
1081 					  (old_iinfo->i_efe ?
1082 					   sizeof(struct extendedFileEntry) :
1083 					   sizeof(struct fileEntry)),
1084 					old_inode->i_sb->s_blocksize, &offset);
1085 		} else {
1086 			dir_bh = udf_bread(old_inode, 0, 0, &retval);
1087 			if (!dir_bh)
1088 				goto end_rename;
1089 			dir_fi = udf_get_fileident(dir_bh->b_data,
1090 					old_inode->i_sb->s_blocksize, &offset);
1091 		}
1092 		if (!dir_fi)
1093 			goto end_rename;
1094 		tloc = lelb_to_cpu(dir_fi->icb.extLocation);
1095 		if (udf_get_lb_pblock(old_inode->i_sb, &tloc, 0) !=
1096 				old_dir->i_ino)
1097 			goto end_rename;
1098 	}
1099 	if (!nfi) {
1100 		nfi = udf_add_entry(new_dir, new_dentry, &nfibh, &ncfi,
1101 				    &retval);
1102 		if (!nfi)
1103 			goto end_rename;
1104 	}
1105 
1106 	/*
1107 	 * Like most other Unix systems, set the ctime for inodes on a
1108 	 * rename.
1109 	 */
1110 	old_inode->i_ctime = current_fs_time(old_inode->i_sb);
1111 	mark_inode_dirty(old_inode);
1112 
1113 	/*
1114 	 * ok, that's it
1115 	 */
1116 	ncfi.fileVersionNum = ocfi.fileVersionNum;
1117 	ncfi.fileCharacteristics = ocfi.fileCharacteristics;
1118 	memcpy(&(ncfi.icb), &(ocfi.icb), sizeof(struct long_ad));
1119 	udf_write_fi(new_dir, &ncfi, nfi, &nfibh, NULL, NULL);
1120 
1121 	/* The old fid may have moved - find it again */
1122 	ofi = udf_find_entry(old_dir, &old_dentry->d_name, &ofibh, &ocfi);
1123 	udf_delete_entry(old_dir, ofi, &ofibh, &ocfi);
1124 
1125 	if (new_inode) {
1126 		new_inode->i_ctime = current_fs_time(new_inode->i_sb);
1127 		inode_dec_link_count(new_inode);
1128 	}
1129 	old_dir->i_ctime = old_dir->i_mtime = current_fs_time(old_dir->i_sb);
1130 	mark_inode_dirty(old_dir);
1131 
1132 	if (dir_fi) {
1133 		dir_fi->icb.extLocation = cpu_to_lelb(UDF_I(new_dir)->i_location);
1134 		udf_update_tag((char *)dir_fi,
1135 				(sizeof(struct fileIdentDesc) +
1136 				le16_to_cpu(dir_fi->lengthOfImpUse) + 3) & ~3);
1137 		if (old_iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
1138 			mark_inode_dirty(old_inode);
1139 		else
1140 			mark_buffer_dirty_inode(dir_bh, old_inode);
1141 
1142 		inode_dec_link_count(old_dir);
1143 		if (new_inode)
1144 			inode_dec_link_count(new_inode);
1145 		else {
1146 			inc_nlink(new_dir);
1147 			mark_inode_dirty(new_dir);
1148 		}
1149 	}
1150 
1151 	if (ofi) {
1152 		if (ofibh.sbh != ofibh.ebh)
1153 			brelse(ofibh.ebh);
1154 		brelse(ofibh.sbh);
1155 	}
1156 
1157 	retval = 0;
1158 
1159 end_rename:
1160 	brelse(dir_bh);
1161 	if (nfi) {
1162 		if (nfibh.sbh != nfibh.ebh)
1163 			brelse(nfibh.ebh);
1164 		brelse(nfibh.sbh);
1165 	}
1166 
1167 	return retval;
1168 }
1169 
1170 static struct dentry *udf_get_parent(struct dentry *child)
1171 {
1172 	struct kernel_lb_addr tloc;
1173 	struct inode *inode = NULL;
1174 	struct qstr dotdot = QSTR_INIT("..", 2);
1175 	struct fileIdentDesc cfi;
1176 	struct udf_fileident_bh fibh;
1177 
1178 	if (!udf_find_entry(child->d_inode, &dotdot, &fibh, &cfi))
1179 		return ERR_PTR(-EACCES);
1180 
1181 	if (fibh.sbh != fibh.ebh)
1182 		brelse(fibh.ebh);
1183 	brelse(fibh.sbh);
1184 
1185 	tloc = lelb_to_cpu(cfi.icb.extLocation);
1186 	inode = udf_iget(child->d_inode->i_sb, &tloc);
1187 	if (IS_ERR(inode))
1188 		return ERR_CAST(inode);
1189 
1190 	return d_obtain_alias(inode);
1191 }
1192 
1193 
1194 static struct dentry *udf_nfs_get_inode(struct super_block *sb, u32 block,
1195 					u16 partref, __u32 generation)
1196 {
1197 	struct inode *inode;
1198 	struct kernel_lb_addr loc;
1199 
1200 	if (block == 0)
1201 		return ERR_PTR(-ESTALE);
1202 
1203 	loc.logicalBlockNum = block;
1204 	loc.partitionReferenceNum = partref;
1205 	inode = udf_iget(sb, &loc);
1206 
1207 	if (IS_ERR(inode))
1208 		return ERR_CAST(inode);
1209 
1210 	if (generation && inode->i_generation != generation) {
1211 		iput(inode);
1212 		return ERR_PTR(-ESTALE);
1213 	}
1214 	return d_obtain_alias(inode);
1215 }
1216 
1217 static struct dentry *udf_fh_to_dentry(struct super_block *sb,
1218 				       struct fid *fid, int fh_len, int fh_type)
1219 {
1220 	if ((fh_len != 3 && fh_len != 5) ||
1221 	    (fh_type != FILEID_UDF_WITH_PARENT &&
1222 	     fh_type != FILEID_UDF_WITHOUT_PARENT))
1223 		return NULL;
1224 
1225 	return udf_nfs_get_inode(sb, fid->udf.block, fid->udf.partref,
1226 			fid->udf.generation);
1227 }
1228 
1229 static struct dentry *udf_fh_to_parent(struct super_block *sb,
1230 				       struct fid *fid, int fh_len, int fh_type)
1231 {
1232 	if (fh_len != 5 || fh_type != FILEID_UDF_WITH_PARENT)
1233 		return NULL;
1234 
1235 	return udf_nfs_get_inode(sb, fid->udf.parent_block,
1236 				 fid->udf.parent_partref,
1237 				 fid->udf.parent_generation);
1238 }
1239 static int udf_encode_fh(struct inode *inode, __u32 *fh, int *lenp,
1240 			 struct inode *parent)
1241 {
1242 	int len = *lenp;
1243 	struct kernel_lb_addr location = UDF_I(inode)->i_location;
1244 	struct fid *fid = (struct fid *)fh;
1245 	int type = FILEID_UDF_WITHOUT_PARENT;
1246 
1247 	if (parent && (len < 5)) {
1248 		*lenp = 5;
1249 		return FILEID_INVALID;
1250 	} else if (len < 3) {
1251 		*lenp = 3;
1252 		return FILEID_INVALID;
1253 	}
1254 
1255 	*lenp = 3;
1256 	fid->udf.block = location.logicalBlockNum;
1257 	fid->udf.partref = location.partitionReferenceNum;
1258 	fid->udf.parent_partref = 0;
1259 	fid->udf.generation = inode->i_generation;
1260 
1261 	if (parent) {
1262 		location = UDF_I(parent)->i_location;
1263 		fid->udf.parent_block = location.logicalBlockNum;
1264 		fid->udf.parent_partref = location.partitionReferenceNum;
1265 		fid->udf.parent_generation = inode->i_generation;
1266 		*lenp = 5;
1267 		type = FILEID_UDF_WITH_PARENT;
1268 	}
1269 
1270 	return type;
1271 }
1272 
1273 const struct export_operations udf_export_ops = {
1274 	.encode_fh	= udf_encode_fh,
1275 	.fh_to_dentry   = udf_fh_to_dentry,
1276 	.fh_to_parent   = udf_fh_to_parent,
1277 	.get_parent     = udf_get_parent,
1278 };
1279 
1280 const struct inode_operations udf_dir_inode_operations = {
1281 	.lookup				= udf_lookup,
1282 	.create				= udf_create,
1283 	.link				= udf_link,
1284 	.unlink				= udf_unlink,
1285 	.symlink			= udf_symlink,
1286 	.mkdir				= udf_mkdir,
1287 	.rmdir				= udf_rmdir,
1288 	.mknod				= udf_mknod,
1289 	.rename				= udf_rename,
1290 	.tmpfile			= udf_tmpfile,
1291 };
1292 const struct inode_operations udf_symlink_inode_operations = {
1293 	.readlink	= generic_readlink,
1294 	.follow_link	= page_follow_link_light,
1295 	.put_link	= page_put_link,
1296 };
1297