xref: /kernel/linux/linux-6.6/fs/udf/namei.c (revision 62306a36)
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
31static 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 */
52static 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
99out_err:
100	udf_fiiter_release(iter);
101out_ok:
102	kfree(fname);
103
104	return ret;
105}
106
107static 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
135static 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
222static 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);
298store_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
325static 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
335static 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
350static 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	dir->i_mtime = 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
377static 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
393static 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
410static 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
426static 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	dir->i_mtime = inode_set_ctime_current(dir);
475	mark_inode_dirty(dir);
476	d_instantiate_new(dentry, inode);
477
478	return 0;
479}
480
481static 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
500static 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	dir->i_mtime = inode_set_ctime_to_ts(dir,
527					     inode_set_ctime_current(inode));
528	mark_inode_dirty(dir);
529	ret = 0;
530end_rmdir:
531	udf_fiiter_release(&iter);
532out:
533	return ret;
534}
535
536static 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	dir->i_mtime = 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;
564end_unlink:
565	udf_fiiter_release(&iter);
566out:
567	return ret;
568}
569
570static 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);
717out:
718	kfree(name);
719	return err;
720
721out_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
728static 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	dir->i_mtime = 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 */
762static 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	old_dir->i_mtime = inode_set_ctime_current(old_dir);
870	new_dir->i_mtime = 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;
891out_oiter:
892	if (has_diriter)
893		udf_fiiter_release(&diriter);
894	udf_fiiter_release(&oiter);
895
896	return retval;
897}
898
899static 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
920static 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
943static 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
955static 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}
965static 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
999const 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
1006const 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};
1018