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