Merge tag 'perf-tools-for-v6.7-1-2023-11-01' of git://git.kernel.org/pub/scm/linux...
[linux-2.6-microblaze.git] / fs / udf / namei.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * namei.c
4  *
5  * PURPOSE
6  *      Inode name handling routines for the OSTA-UDF(tm) filesystem.
7  *
8  * COPYRIGHT
9  *  (C) 1998-2004 Ben Fennema
10  *  (C) 1999-2000 Stelias Computing Inc
11  *
12  * HISTORY
13  *
14  *  12/12/98 blf  Created. Split out the lookup code from dir.c
15  *  04/19/99 blf  link, mknod, symlink support
16  */
17
18 #include "udfdecl.h"
19
20 #include "udf_i.h"
21 #include "udf_sb.h"
22 #include <linux/string.h>
23 #include <linux/errno.h>
24 #include <linux/mm.h>
25 #include <linux/slab.h>
26 #include <linux/sched.h>
27 #include <linux/crc-itu-t.h>
28 #include <linux/exportfs.h>
29 #include <linux/iversion.h>
30
31 static inline int udf_match(int len1, const unsigned char *name1, int len2,
32                             const unsigned char *name2)
33 {
34         if (len1 != len2)
35                 return 0;
36
37         return !memcmp(name1, name2, len1);
38 }
39
40 /**
41  * udf_fiiter_find_entry - find entry in given directory.
42  *
43  * @dir:        directory inode to search in
44  * @child:      qstr of the name
45  * @iter:       iter to use for searching
46  *
47  * This function searches in the directory @dir for a file name @child. When
48  * found, @iter points to the position in the directory with given entry.
49  *
50  * Returns 0 on success, < 0 on error (including -ENOENT).
51  */
52 static int udf_fiiter_find_entry(struct inode *dir, const struct qstr *child,
53                                  struct udf_fileident_iter *iter)
54 {
55         int flen;
56         unsigned char *fname = NULL;
57         struct super_block *sb = dir->i_sb;
58         int isdotdot = child->len == 2 &&
59                 child->name[0] == '.' && child->name[1] == '.';
60         int ret;
61
62         fname = kmalloc(UDF_NAME_LEN, GFP_NOFS);
63         if (!fname)
64                 return -ENOMEM;
65
66         for (ret = udf_fiiter_init(iter, dir, 0);
67              !ret && iter->pos < dir->i_size;
68              ret = udf_fiiter_advance(iter)) {
69                 if (iter->fi.fileCharacteristics & FID_FILE_CHAR_DELETED) {
70                         if (!UDF_QUERY_FLAG(sb, UDF_FLAG_UNDELETE))
71                                 continue;
72                 }
73
74                 if (iter->fi.fileCharacteristics & FID_FILE_CHAR_HIDDEN) {
75                         if (!UDF_QUERY_FLAG(sb, UDF_FLAG_UNHIDE))
76                                 continue;
77                 }
78
79                 if ((iter->fi.fileCharacteristics & FID_FILE_CHAR_PARENT) &&
80                     isdotdot)
81                         goto out_ok;
82
83                 if (!iter->fi.lengthFileIdent)
84                         continue;
85
86                 flen = udf_get_filename(sb, iter->name,
87                                 iter->fi.lengthFileIdent, fname, UDF_NAME_LEN);
88                 if (flen < 0) {
89                         ret = flen;
90                         goto out_err;
91                 }
92
93                 if (udf_match(flen, fname, child->len, child->name))
94                         goto out_ok;
95         }
96         if (!ret)
97                 ret = -ENOENT;
98
99 out_err:
100         udf_fiiter_release(iter);
101 out_ok:
102         kfree(fname);
103
104         return ret;
105 }
106
107 static struct dentry *udf_lookup(struct inode *dir, struct dentry *dentry,
108                                  unsigned int flags)
109 {
110         struct inode *inode = NULL;
111         struct udf_fileident_iter iter;
112         int err;
113
114         if (dentry->d_name.len > UDF_NAME_LEN)
115                 return ERR_PTR(-ENAMETOOLONG);
116
117         err = udf_fiiter_find_entry(dir, &dentry->d_name, &iter);
118         if (err < 0 && err != -ENOENT)
119                 return ERR_PTR(err);
120
121         if (err == 0) {
122                 struct kernel_lb_addr loc;
123
124                 loc = lelb_to_cpu(iter.fi.icb.extLocation);
125                 udf_fiiter_release(&iter);
126
127                 inode = udf_iget(dir->i_sb, &loc);
128                 if (IS_ERR(inode))
129                         return ERR_CAST(inode);
130         }
131
132         return d_splice_alias(inode, dentry);
133 }
134
135 static int udf_expand_dir_adinicb(struct inode *inode, udf_pblk_t *block)
136 {
137         udf_pblk_t newblock;
138         struct buffer_head *dbh = NULL;
139         struct kernel_lb_addr eloc;
140         struct extent_position epos;
141         uint8_t alloctype;
142         struct udf_inode_info *iinfo = UDF_I(inode);
143         struct udf_fileident_iter iter;
144         uint8_t *impuse;
145         int ret;
146
147         if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
148                 alloctype = ICBTAG_FLAG_AD_SHORT;
149         else
150                 alloctype = ICBTAG_FLAG_AD_LONG;
151
152         if (!inode->i_size) {
153                 iinfo->i_alloc_type = alloctype;
154                 mark_inode_dirty(inode);
155                 return 0;
156         }
157
158         /* alloc block, and copy data to it */
159         *block = udf_new_block(inode->i_sb, inode,
160                                iinfo->i_location.partitionReferenceNum,
161                                iinfo->i_location.logicalBlockNum, &ret);
162         if (!(*block))
163                 return ret;
164         newblock = udf_get_pblock(inode->i_sb, *block,
165                                   iinfo->i_location.partitionReferenceNum,
166                                 0);
167         if (newblock == 0xffffffff)
168                 return -EFSCORRUPTED;
169         dbh = sb_getblk(inode->i_sb, newblock);
170         if (!dbh)
171                 return -ENOMEM;
172         lock_buffer(dbh);
173         memcpy(dbh->b_data, iinfo->i_data, inode->i_size);
174         memset(dbh->b_data + inode->i_size, 0,
175                inode->i_sb->s_blocksize - inode->i_size);
176         set_buffer_uptodate(dbh);
177         unlock_buffer(dbh);
178
179         /* Drop inline data, add block instead */
180         iinfo->i_alloc_type = alloctype;
181         memset(iinfo->i_data + iinfo->i_lenEAttr, 0, iinfo->i_lenAlloc);
182         iinfo->i_lenAlloc = 0;
183         eloc.logicalBlockNum = *block;
184         eloc.partitionReferenceNum =
185                                 iinfo->i_location.partitionReferenceNum;
186         iinfo->i_lenExtents = inode->i_size;
187         epos.bh = NULL;
188         epos.block = iinfo->i_location;
189         epos.offset = udf_file_entry_alloc_offset(inode);
190         ret = udf_add_aext(inode, &epos, &eloc, inode->i_size, 0);
191         brelse(epos.bh);
192         if (ret < 0) {
193                 brelse(dbh);
194                 udf_free_blocks(inode->i_sb, inode, &eloc, 0, 1);
195                 return ret;
196         }
197         mark_inode_dirty(inode);
198
199         /* Now fixup tags in moved directory entries */
200         for (ret = udf_fiiter_init(&iter, inode, 0);
201              !ret && iter.pos < inode->i_size;
202              ret = udf_fiiter_advance(&iter)) {
203                 iter.fi.descTag.tagLocation = cpu_to_le32(*block);
204                 if (iter.fi.lengthOfImpUse != cpu_to_le16(0))
205                         impuse = dbh->b_data + iter.pos +
206                                                 sizeof(struct fileIdentDesc);
207                 else
208                         impuse = NULL;
209                 udf_fiiter_write_fi(&iter, impuse);
210         }
211         brelse(dbh);
212         /*
213          * We don't expect the iteration to fail as the directory has been
214          * already verified to be correct
215          */
216         WARN_ON_ONCE(ret);
217         udf_fiiter_release(&iter);
218
219         return 0;
220 }
221
222 static int udf_fiiter_add_entry(struct inode *dir, struct dentry *dentry,
223                                 struct udf_fileident_iter *iter)
224 {
225         struct udf_inode_info *dinfo = UDF_I(dir);
226         int nfidlen, namelen = 0;
227         int ret;
228         int off, blksize = 1 << dir->i_blkbits;
229         udf_pblk_t block;
230         char name[UDF_NAME_LEN_CS0];
231
232         if (dentry) {
233                 if (!dentry->d_name.len)
234                         return -EINVAL;
235                 namelen = udf_put_filename(dir->i_sb, dentry->d_name.name,
236                                            dentry->d_name.len,
237                                            name, UDF_NAME_LEN_CS0);
238                 if (!namelen)
239                         return -ENAMETOOLONG;
240         }
241         nfidlen = ALIGN(sizeof(struct fileIdentDesc) + namelen, UDF_NAME_PAD);
242
243         for (ret = udf_fiiter_init(iter, dir, 0);
244              !ret && iter->pos < dir->i_size;
245              ret = udf_fiiter_advance(iter)) {
246                 if (iter->fi.fileCharacteristics & FID_FILE_CHAR_DELETED) {
247                         if (udf_dir_entry_len(&iter->fi) == nfidlen) {
248                                 iter->fi.descTag.tagSerialNum = cpu_to_le16(1);
249                                 iter->fi.fileVersionNum = cpu_to_le16(1);
250                                 iter->fi.fileCharacteristics = 0;
251                                 iter->fi.lengthFileIdent = namelen;
252                                 iter->fi.lengthOfImpUse = cpu_to_le16(0);
253                                 memcpy(iter->namebuf, name, namelen);
254                                 iter->name = iter->namebuf;
255                                 return 0;
256                         }
257                 }
258         }
259         if (ret) {
260                 udf_fiiter_release(iter);
261                 return ret;
262         }
263         if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB &&
264             blksize - udf_ext0_offset(dir) - iter->pos < nfidlen) {
265                 udf_fiiter_release(iter);
266                 ret = udf_expand_dir_adinicb(dir, &block);
267                 if (ret)
268                         return ret;
269                 ret = udf_fiiter_init(iter, dir, dir->i_size);
270                 if (ret < 0)
271                         return ret;
272         }
273
274         /* Get blocknumber to use for entry tag */
275         if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
276                 block = dinfo->i_location.logicalBlockNum;
277         } else {
278                 block = iter->eloc.logicalBlockNum +
279                                 ((iter->elen - 1) >> dir->i_blkbits);
280         }
281         off = iter->pos & (blksize - 1);
282         if (!off)
283                 off = blksize;
284         /* Entry fits into current block? */
285         if (blksize - udf_ext0_offset(dir) - off >= nfidlen)
286                 goto store_fi;
287
288         ret = udf_fiiter_append_blk(iter);
289         if (ret) {
290                 udf_fiiter_release(iter);
291                 return ret;
292         }
293
294         /* Entry will be completely in the new block? Update tag location... */
295         if (!(iter->pos & (blksize - 1)))
296                 block = iter->eloc.logicalBlockNum +
297                                 ((iter->elen - 1) >> dir->i_blkbits);
298 store_fi:
299         memset(&iter->fi, 0, sizeof(struct fileIdentDesc));
300         if (UDF_SB(dir->i_sb)->s_udfrev >= 0x0200)
301                 udf_new_tag((char *)(&iter->fi), TAG_IDENT_FID, 3, 1, block,
302                             sizeof(struct tag));
303         else
304                 udf_new_tag((char *)(&iter->fi), TAG_IDENT_FID, 2, 1, block,
305                             sizeof(struct tag));
306         iter->fi.fileVersionNum = cpu_to_le16(1);
307         iter->fi.lengthFileIdent = namelen;
308         iter->fi.lengthOfImpUse = cpu_to_le16(0);
309         memcpy(iter->namebuf, name, namelen);
310         iter->name = iter->namebuf;
311
312         dir->i_size += nfidlen;
313         if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
314                 dinfo->i_lenAlloc += nfidlen;
315         } else {
316                 /* Truncate last extent to proper size */
317                 udf_fiiter_update_elen(iter, iter->elen -
318                                         (dinfo->i_lenExtents - dir->i_size));
319         }
320         mark_inode_dirty(dir);
321
322         return 0;
323 }
324
325 static void udf_fiiter_delete_entry(struct udf_fileident_iter *iter)
326 {
327         iter->fi.fileCharacteristics |= FID_FILE_CHAR_DELETED;
328
329         if (UDF_QUERY_FLAG(iter->dir->i_sb, UDF_FLAG_STRICT))
330                 memset(&iter->fi.icb, 0x00, sizeof(struct long_ad));
331
332         udf_fiiter_write_fi(iter, NULL);
333 }
334
335 static void udf_add_fid_counter(struct super_block *sb, bool dir, int val)
336 {
337         struct logicalVolIntegrityDescImpUse *lvidiu = udf_sb_lvidiu(sb);
338
339         if (!lvidiu)
340                 return;
341         mutex_lock(&UDF_SB(sb)->s_alloc_mutex);
342         if (dir)
343                 le32_add_cpu(&lvidiu->numDirs, val);
344         else
345                 le32_add_cpu(&lvidiu->numFiles, val);
346         udf_updated_lvid(sb);
347         mutex_unlock(&UDF_SB(sb)->s_alloc_mutex);
348 }
349
350 static int udf_add_nondir(struct dentry *dentry, struct inode *inode)
351 {
352         struct udf_inode_info *iinfo = UDF_I(inode);
353         struct inode *dir = d_inode(dentry->d_parent);
354         struct udf_fileident_iter iter;
355         int err;
356
357         err = udf_fiiter_add_entry(dir, dentry, &iter);
358         if (err) {
359                 inode_dec_link_count(inode);
360                 discard_new_inode(inode);
361                 return err;
362         }
363         iter.fi.icb.extLength = cpu_to_le32(inode->i_sb->s_blocksize);
364         iter.fi.icb.extLocation = cpu_to_lelb(iinfo->i_location);
365         *(__le32 *)((struct allocDescImpUse *)iter.fi.icb.impUse)->impUse =
366                 cpu_to_le32(iinfo->i_unique & 0x00000000FFFFFFFFUL);
367         udf_fiiter_write_fi(&iter, NULL);
368         inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
369         mark_inode_dirty(dir);
370         udf_fiiter_release(&iter);
371         udf_add_fid_counter(dir->i_sb, false, 1);
372         d_instantiate_new(dentry, inode);
373
374         return 0;
375 }
376
377 static int udf_create(struct mnt_idmap *idmap, struct inode *dir,
378                       struct dentry *dentry, umode_t mode, bool excl)
379 {
380         struct inode *inode = udf_new_inode(dir, mode);
381
382         if (IS_ERR(inode))
383                 return PTR_ERR(inode);
384
385         inode->i_data.a_ops = &udf_aops;
386         inode->i_op = &udf_file_inode_operations;
387         inode->i_fop = &udf_file_operations;
388         mark_inode_dirty(inode);
389
390         return udf_add_nondir(dentry, inode);
391 }
392
393 static int udf_tmpfile(struct mnt_idmap *idmap, struct inode *dir,
394                        struct file *file, umode_t mode)
395 {
396         struct inode *inode = udf_new_inode(dir, mode);
397
398         if (IS_ERR(inode))
399                 return PTR_ERR(inode);
400
401         inode->i_data.a_ops = &udf_aops;
402         inode->i_op = &udf_file_inode_operations;
403         inode->i_fop = &udf_file_operations;
404         mark_inode_dirty(inode);
405         d_tmpfile(file, inode);
406         unlock_new_inode(inode);
407         return finish_open_simple(file, 0);
408 }
409
410 static int udf_mknod(struct mnt_idmap *idmap, struct inode *dir,
411                      struct dentry *dentry, umode_t mode, dev_t rdev)
412 {
413         struct inode *inode;
414
415         if (!old_valid_dev(rdev))
416                 return -EINVAL;
417
418         inode = udf_new_inode(dir, mode);
419         if (IS_ERR(inode))
420                 return PTR_ERR(inode);
421
422         init_special_inode(inode, mode, rdev);
423         return udf_add_nondir(dentry, inode);
424 }
425
426 static int udf_mkdir(struct mnt_idmap *idmap, struct inode *dir,
427                      struct dentry *dentry, umode_t mode)
428 {
429         struct inode *inode;
430         struct udf_fileident_iter iter;
431         int err;
432         struct udf_inode_info *dinfo = UDF_I(dir);
433         struct udf_inode_info *iinfo;
434
435         inode = udf_new_inode(dir, S_IFDIR | mode);
436         if (IS_ERR(inode))
437                 return PTR_ERR(inode);
438
439         iinfo = UDF_I(inode);
440         inode->i_op = &udf_dir_inode_operations;
441         inode->i_fop = &udf_dir_operations;
442         err = udf_fiiter_add_entry(inode, NULL, &iter);
443         if (err) {
444                 clear_nlink(inode);
445                 discard_new_inode(inode);
446                 return err;
447         }
448         set_nlink(inode, 2);
449         iter.fi.icb.extLength = cpu_to_le32(inode->i_sb->s_blocksize);
450         iter.fi.icb.extLocation = cpu_to_lelb(dinfo->i_location);
451         *(__le32 *)((struct allocDescImpUse *)iter.fi.icb.impUse)->impUse =
452                 cpu_to_le32(dinfo->i_unique & 0x00000000FFFFFFFFUL);
453         iter.fi.fileCharacteristics =
454                         FID_FILE_CHAR_DIRECTORY | FID_FILE_CHAR_PARENT;
455         udf_fiiter_write_fi(&iter, NULL);
456         udf_fiiter_release(&iter);
457         mark_inode_dirty(inode);
458
459         err = udf_fiiter_add_entry(dir, dentry, &iter);
460         if (err) {
461                 clear_nlink(inode);
462                 discard_new_inode(inode);
463                 return err;
464         }
465         iter.fi.icb.extLength = cpu_to_le32(inode->i_sb->s_blocksize);
466         iter.fi.icb.extLocation = cpu_to_lelb(iinfo->i_location);
467         *(__le32 *)((struct allocDescImpUse *)iter.fi.icb.impUse)->impUse =
468                 cpu_to_le32(iinfo->i_unique & 0x00000000FFFFFFFFUL);
469         iter.fi.fileCharacteristics |= FID_FILE_CHAR_DIRECTORY;
470         udf_fiiter_write_fi(&iter, NULL);
471         udf_fiiter_release(&iter);
472         udf_add_fid_counter(dir->i_sb, true, 1);
473         inc_nlink(dir);
474         inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
475         mark_inode_dirty(dir);
476         d_instantiate_new(dentry, inode);
477
478         return 0;
479 }
480
481 static int empty_dir(struct inode *dir)
482 {
483         struct udf_fileident_iter iter;
484         int ret;
485
486         for (ret = udf_fiiter_init(&iter, dir, 0);
487              !ret && iter.pos < dir->i_size;
488              ret = udf_fiiter_advance(&iter)) {
489                 if (iter.fi.lengthFileIdent &&
490                     !(iter.fi.fileCharacteristics & FID_FILE_CHAR_DELETED)) {
491                         udf_fiiter_release(&iter);
492                         return 0;
493                 }
494         }
495         udf_fiiter_release(&iter);
496
497         return 1;
498 }
499
500 static int udf_rmdir(struct inode *dir, struct dentry *dentry)
501 {
502         int ret;
503         struct inode *inode = d_inode(dentry);
504         struct udf_fileident_iter iter;
505         struct kernel_lb_addr tloc;
506
507         ret = udf_fiiter_find_entry(dir, &dentry->d_name, &iter);
508         if (ret)
509                 goto out;
510
511         ret = -EFSCORRUPTED;
512         tloc = lelb_to_cpu(iter.fi.icb.extLocation);
513         if (udf_get_lb_pblock(dir->i_sb, &tloc, 0) != inode->i_ino)
514                 goto end_rmdir;
515         ret = -ENOTEMPTY;
516         if (!empty_dir(inode))
517                 goto end_rmdir;
518         udf_fiiter_delete_entry(&iter);
519         if (inode->i_nlink != 2)
520                 udf_warn(inode->i_sb, "empty directory has nlink != 2 (%u)\n",
521                          inode->i_nlink);
522         clear_nlink(inode);
523         inode->i_size = 0;
524         inode_dec_link_count(dir);
525         udf_add_fid_counter(dir->i_sb, true, -1);
526         inode_set_mtime_to_ts(dir,
527                               inode_set_ctime_to_ts(dir, inode_set_ctime_current(inode)));
528         mark_inode_dirty(dir);
529         ret = 0;
530 end_rmdir:
531         udf_fiiter_release(&iter);
532 out:
533         return ret;
534 }
535
536 static int udf_unlink(struct inode *dir, struct dentry *dentry)
537 {
538         int ret;
539         struct inode *inode = d_inode(dentry);
540         struct udf_fileident_iter iter;
541         struct kernel_lb_addr tloc;
542
543         ret = udf_fiiter_find_entry(dir, &dentry->d_name, &iter);
544         if (ret)
545                 goto out;
546
547         ret = -EFSCORRUPTED;
548         tloc = lelb_to_cpu(iter.fi.icb.extLocation);
549         if (udf_get_lb_pblock(dir->i_sb, &tloc, 0) != inode->i_ino)
550                 goto end_unlink;
551
552         if (!inode->i_nlink) {
553                 udf_debug("Deleting nonexistent file (%lu), %u\n",
554                           inode->i_ino, inode->i_nlink);
555                 set_nlink(inode, 1);
556         }
557         udf_fiiter_delete_entry(&iter);
558         inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
559         mark_inode_dirty(dir);
560         inode_dec_link_count(inode);
561         udf_add_fid_counter(dir->i_sb, false, -1);
562         inode_set_ctime_to_ts(inode, inode_get_ctime(dir));
563         ret = 0;
564 end_unlink:
565         udf_fiiter_release(&iter);
566 out:
567         return ret;
568 }
569
570 static int udf_symlink(struct mnt_idmap *idmap, struct inode *dir,
571                        struct dentry *dentry, const char *symname)
572 {
573         struct inode *inode = udf_new_inode(dir, S_IFLNK | 0777);
574         struct pathComponent *pc;
575         const char *compstart;
576         struct extent_position epos = {};
577         int eoffset, elen = 0;
578         uint8_t *ea;
579         int err;
580         udf_pblk_t block;
581         unsigned char *name = NULL;
582         int namelen;
583         struct udf_inode_info *iinfo;
584         struct super_block *sb = dir->i_sb;
585
586         if (IS_ERR(inode))
587                 return PTR_ERR(inode);
588
589         iinfo = UDF_I(inode);
590         down_write(&iinfo->i_data_sem);
591         name = kmalloc(UDF_NAME_LEN_CS0, GFP_NOFS);
592         if (!name) {
593                 err = -ENOMEM;
594                 goto out_no_entry;
595         }
596
597         inode->i_data.a_ops = &udf_symlink_aops;
598         inode->i_op = &udf_symlink_inode_operations;
599         inode_nohighmem(inode);
600
601         if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
602                 struct kernel_lb_addr eloc;
603                 uint32_t bsize;
604
605                 block = udf_new_block(sb, inode,
606                                 iinfo->i_location.partitionReferenceNum,
607                                 iinfo->i_location.logicalBlockNum, &err);
608                 if (!block)
609                         goto out_no_entry;
610                 epos.block = iinfo->i_location;
611                 epos.offset = udf_file_entry_alloc_offset(inode);
612                 epos.bh = NULL;
613                 eloc.logicalBlockNum = block;
614                 eloc.partitionReferenceNum =
615                                 iinfo->i_location.partitionReferenceNum;
616                 bsize = sb->s_blocksize;
617                 iinfo->i_lenExtents = bsize;
618                 err = udf_add_aext(inode, &epos, &eloc, bsize, 0);
619                 brelse(epos.bh);
620                 if (err < 0) {
621                         udf_free_blocks(sb, inode, &eloc, 0, 1);
622                         goto out_no_entry;
623                 }
624
625                 block = udf_get_pblock(sb, block,
626                                 iinfo->i_location.partitionReferenceNum,
627                                 0);
628                 epos.bh = sb_getblk(sb, block);
629                 if (unlikely(!epos.bh)) {
630                         err = -ENOMEM;
631                         udf_free_blocks(sb, inode, &eloc, 0, 1);
632                         goto out_no_entry;
633                 }
634                 lock_buffer(epos.bh);
635                 memset(epos.bh->b_data, 0x00, bsize);
636                 set_buffer_uptodate(epos.bh);
637                 unlock_buffer(epos.bh);
638                 mark_buffer_dirty_inode(epos.bh, inode);
639                 ea = epos.bh->b_data + udf_ext0_offset(inode);
640         } else
641                 ea = iinfo->i_data + iinfo->i_lenEAttr;
642
643         eoffset = sb->s_blocksize - udf_ext0_offset(inode);
644         pc = (struct pathComponent *)ea;
645
646         if (*symname == '/') {
647                 do {
648                         symname++;
649                 } while (*symname == '/');
650
651                 pc->componentType = 1;
652                 pc->lengthComponentIdent = 0;
653                 pc->componentFileVersionNum = 0;
654                 elen += sizeof(struct pathComponent);
655         }
656
657         err = -ENAMETOOLONG;
658
659         while (*symname) {
660                 if (elen + sizeof(struct pathComponent) > eoffset)
661                         goto out_no_entry;
662
663                 pc = (struct pathComponent *)(ea + elen);
664
665                 compstart = symname;
666
667                 do {
668                         symname++;
669                 } while (*symname && *symname != '/');
670
671                 pc->componentType = 5;
672                 pc->lengthComponentIdent = 0;
673                 pc->componentFileVersionNum = 0;
674                 if (compstart[0] == '.') {
675                         if ((symname - compstart) == 1)
676                                 pc->componentType = 4;
677                         else if ((symname - compstart) == 2 &&
678                                         compstart[1] == '.')
679                                 pc->componentType = 3;
680                 }
681
682                 if (pc->componentType == 5) {
683                         namelen = udf_put_filename(sb, compstart,
684                                                    symname - compstart,
685                                                    name, UDF_NAME_LEN_CS0);
686                         if (!namelen)
687                                 goto out_no_entry;
688
689                         if (elen + sizeof(struct pathComponent) + namelen >
690                                         eoffset)
691                                 goto out_no_entry;
692                         else
693                                 pc->lengthComponentIdent = namelen;
694
695                         memcpy(pc->componentIdent, name, namelen);
696                 }
697
698                 elen += sizeof(struct pathComponent) + pc->lengthComponentIdent;
699
700                 if (*symname) {
701                         do {
702                                 symname++;
703                         } while (*symname == '/');
704                 }
705         }
706
707         brelse(epos.bh);
708         inode->i_size = elen;
709         if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
710                 iinfo->i_lenAlloc = inode->i_size;
711         else
712                 udf_truncate_tail_extent(inode);
713         mark_inode_dirty(inode);
714         up_write(&iinfo->i_data_sem);
715
716         err = udf_add_nondir(dentry, inode);
717 out:
718         kfree(name);
719         return err;
720
721 out_no_entry:
722         up_write(&iinfo->i_data_sem);
723         inode_dec_link_count(inode);
724         discard_new_inode(inode);
725         goto out;
726 }
727
728 static int udf_link(struct dentry *old_dentry, struct inode *dir,
729                     struct dentry *dentry)
730 {
731         struct inode *inode = d_inode(old_dentry);
732         struct udf_fileident_iter iter;
733         int err;
734
735         err = udf_fiiter_add_entry(dir, dentry, &iter);
736         if (err)
737                 return err;
738         iter.fi.icb.extLength = cpu_to_le32(inode->i_sb->s_blocksize);
739         iter.fi.icb.extLocation = cpu_to_lelb(UDF_I(inode)->i_location);
740         if (UDF_SB(inode->i_sb)->s_lvid_bh) {
741                 *(__le32 *)((struct allocDescImpUse *)iter.fi.icb.impUse)->impUse =
742                         cpu_to_le32(lvid_get_unique_id(inode->i_sb));
743         }
744         udf_fiiter_write_fi(&iter, NULL);
745         udf_fiiter_release(&iter);
746
747         inc_nlink(inode);
748         udf_add_fid_counter(dir->i_sb, false, 1);
749         inode_set_ctime_current(inode);
750         mark_inode_dirty(inode);
751         inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
752         mark_inode_dirty(dir);
753         ihold(inode);
754         d_instantiate(dentry, inode);
755
756         return 0;
757 }
758
759 /* Anybody can rename anything with this: the permission checks are left to the
760  * higher-level routines.
761  */
762 static int udf_rename(struct mnt_idmap *idmap, struct inode *old_dir,
763                       struct dentry *old_dentry, struct inode *new_dir,
764                       struct dentry *new_dentry, unsigned int flags)
765 {
766         struct inode *old_inode = d_inode(old_dentry);
767         struct inode *new_inode = d_inode(new_dentry);
768         struct udf_fileident_iter oiter, niter, diriter;
769         bool has_diriter = false;
770         int retval;
771         struct kernel_lb_addr tloc;
772
773         if (flags & ~RENAME_NOREPLACE)
774                 return -EINVAL;
775
776         retval = udf_fiiter_find_entry(old_dir, &old_dentry->d_name, &oiter);
777         if (retval)
778                 return retval;
779
780         tloc = lelb_to_cpu(oiter.fi.icb.extLocation);
781         if (udf_get_lb_pblock(old_dir->i_sb, &tloc, 0) != old_inode->i_ino) {
782                 retval = -ENOENT;
783                 goto out_oiter;
784         }
785
786         if (S_ISDIR(old_inode->i_mode)) {
787                 if (new_inode) {
788                         retval = -ENOTEMPTY;
789                         if (!empty_dir(new_inode))
790                                 goto out_oiter;
791                 }
792                 retval = udf_fiiter_find_entry(old_inode, &dotdot_name,
793                                                &diriter);
794                 if (retval == -ENOENT) {
795                         udf_err(old_inode->i_sb,
796                                 "directory (ino %lu) has no '..' entry\n",
797                                 old_inode->i_ino);
798                         retval = -EFSCORRUPTED;
799                 }
800                 if (retval)
801                         goto out_oiter;
802                 has_diriter = true;
803                 tloc = lelb_to_cpu(diriter.fi.icb.extLocation);
804                 if (udf_get_lb_pblock(old_inode->i_sb, &tloc, 0) !=
805                                 old_dir->i_ino) {
806                         retval = -EFSCORRUPTED;
807                         udf_err(old_inode->i_sb,
808                                 "directory (ino %lu) has parent entry pointing to another inode (%lu != %u)\n",
809                                 old_inode->i_ino, old_dir->i_ino,
810                                 udf_get_lb_pblock(old_inode->i_sb, &tloc, 0));
811                         goto out_oiter;
812                 }
813         }
814
815         retval = udf_fiiter_find_entry(new_dir, &new_dentry->d_name, &niter);
816         if (retval && retval != -ENOENT)
817                 goto out_oiter;
818         /* Entry found but not passed by VFS? */
819         if (!retval && !new_inode) {
820                 retval = -EFSCORRUPTED;
821                 udf_fiiter_release(&niter);
822                 goto out_oiter;
823         }
824         /* Entry not found? Need to add one... */
825         if (retval) {
826                 udf_fiiter_release(&niter);
827                 retval = udf_fiiter_add_entry(new_dir, new_dentry, &niter);
828                 if (retval)
829                         goto out_oiter;
830         }
831
832         /*
833          * Like most other Unix systems, set the ctime for inodes on a
834          * rename.
835          */
836         inode_set_ctime_current(old_inode);
837         mark_inode_dirty(old_inode);
838
839         /*
840          * ok, that's it
841          */
842         niter.fi.fileVersionNum = oiter.fi.fileVersionNum;
843         niter.fi.fileCharacteristics = oiter.fi.fileCharacteristics;
844         memcpy(&(niter.fi.icb), &(oiter.fi.icb), sizeof(oiter.fi.icb));
845         udf_fiiter_write_fi(&niter, NULL);
846         udf_fiiter_release(&niter);
847
848         /*
849          * The old entry may have moved due to new entry allocation. Find it
850          * again.
851          */
852         udf_fiiter_release(&oiter);
853         retval = udf_fiiter_find_entry(old_dir, &old_dentry->d_name, &oiter);
854         if (retval) {
855                 udf_err(old_dir->i_sb,
856                         "failed to find renamed entry again in directory (ino %lu)\n",
857                         old_dir->i_ino);
858         } else {
859                 udf_fiiter_delete_entry(&oiter);
860                 udf_fiiter_release(&oiter);
861         }
862
863         if (new_inode) {
864                 inode_set_ctime_current(new_inode);
865                 inode_dec_link_count(new_inode);
866                 udf_add_fid_counter(old_dir->i_sb, S_ISDIR(new_inode->i_mode),
867                                     -1);
868         }
869         inode_set_mtime_to_ts(old_dir, inode_set_ctime_current(old_dir));
870         inode_set_mtime_to_ts(new_dir, inode_set_ctime_current(new_dir));
871         mark_inode_dirty(old_dir);
872         mark_inode_dirty(new_dir);
873
874         if (has_diriter) {
875                 diriter.fi.icb.extLocation =
876                                         cpu_to_lelb(UDF_I(new_dir)->i_location);
877                 udf_update_tag((char *)&diriter.fi,
878                                udf_dir_entry_len(&diriter.fi));
879                 udf_fiiter_write_fi(&diriter, NULL);
880                 udf_fiiter_release(&diriter);
881
882                 inode_dec_link_count(old_dir);
883                 if (new_inode)
884                         inode_dec_link_count(new_inode);
885                 else {
886                         inc_nlink(new_dir);
887                         mark_inode_dirty(new_dir);
888                 }
889         }
890         return 0;
891 out_oiter:
892         if (has_diriter)
893                 udf_fiiter_release(&diriter);
894         udf_fiiter_release(&oiter);
895
896         return retval;
897 }
898
899 static struct dentry *udf_get_parent(struct dentry *child)
900 {
901         struct kernel_lb_addr tloc;
902         struct inode *inode = NULL;
903         struct udf_fileident_iter iter;
904         int err;
905
906         err = udf_fiiter_find_entry(d_inode(child), &dotdot_name, &iter);
907         if (err)
908                 return ERR_PTR(err);
909
910         tloc = lelb_to_cpu(iter.fi.icb.extLocation);
911         udf_fiiter_release(&iter);
912         inode = udf_iget(child->d_sb, &tloc);
913         if (IS_ERR(inode))
914                 return ERR_CAST(inode);
915
916         return d_obtain_alias(inode);
917 }
918
919
920 static struct dentry *udf_nfs_get_inode(struct super_block *sb, u32 block,
921                                         u16 partref, __u32 generation)
922 {
923         struct inode *inode;
924         struct kernel_lb_addr loc;
925
926         if (block == 0)
927                 return ERR_PTR(-ESTALE);
928
929         loc.logicalBlockNum = block;
930         loc.partitionReferenceNum = partref;
931         inode = udf_iget(sb, &loc);
932
933         if (IS_ERR(inode))
934                 return ERR_CAST(inode);
935
936         if (generation && inode->i_generation != generation) {
937                 iput(inode);
938                 return ERR_PTR(-ESTALE);
939         }
940         return d_obtain_alias(inode);
941 }
942
943 static struct dentry *udf_fh_to_dentry(struct super_block *sb,
944                                        struct fid *fid, int fh_len, int fh_type)
945 {
946         if (fh_len < 3 ||
947             (fh_type != FILEID_UDF_WITH_PARENT &&
948              fh_type != FILEID_UDF_WITHOUT_PARENT))
949                 return NULL;
950
951         return udf_nfs_get_inode(sb, fid->udf.block, fid->udf.partref,
952                         fid->udf.generation);
953 }
954
955 static struct dentry *udf_fh_to_parent(struct super_block *sb,
956                                        struct fid *fid, int fh_len, int fh_type)
957 {
958         if (fh_len < 5 || fh_type != FILEID_UDF_WITH_PARENT)
959                 return NULL;
960
961         return udf_nfs_get_inode(sb, fid->udf.parent_block,
962                                  fid->udf.parent_partref,
963                                  fid->udf.parent_generation);
964 }
965 static int udf_encode_fh(struct inode *inode, __u32 *fh, int *lenp,
966                          struct inode *parent)
967 {
968         int len = *lenp;
969         struct kernel_lb_addr location = UDF_I(inode)->i_location;
970         struct fid *fid = (struct fid *)fh;
971         int type = FILEID_UDF_WITHOUT_PARENT;
972
973         if (parent && (len < 5)) {
974                 *lenp = 5;
975                 return FILEID_INVALID;
976         } else if (len < 3) {
977                 *lenp = 3;
978                 return FILEID_INVALID;
979         }
980
981         *lenp = 3;
982         fid->udf.block = location.logicalBlockNum;
983         fid->udf.partref = location.partitionReferenceNum;
984         fid->udf.parent_partref = 0;
985         fid->udf.generation = inode->i_generation;
986
987         if (parent) {
988                 location = UDF_I(parent)->i_location;
989                 fid->udf.parent_block = location.logicalBlockNum;
990                 fid->udf.parent_partref = location.partitionReferenceNum;
991                 fid->udf.parent_generation = inode->i_generation;
992                 *lenp = 5;
993                 type = FILEID_UDF_WITH_PARENT;
994         }
995
996         return type;
997 }
998
999 const struct export_operations udf_export_ops = {
1000         .encode_fh      = udf_encode_fh,
1001         .fh_to_dentry   = udf_fh_to_dentry,
1002         .fh_to_parent   = udf_fh_to_parent,
1003         .get_parent     = udf_get_parent,
1004 };
1005
1006 const struct inode_operations udf_dir_inode_operations = {
1007         .lookup                         = udf_lookup,
1008         .create                         = udf_create,
1009         .link                           = udf_link,
1010         .unlink                         = udf_unlink,
1011         .symlink                        = udf_symlink,
1012         .mkdir                          = udf_mkdir,
1013         .rmdir                          = udf_rmdir,
1014         .mknod                          = udf_mknod,
1015         .rename                         = udf_rename,
1016         .tmpfile                        = udf_tmpfile,
1017 };