1/*-
2 * Copyright (c) 1989, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley
6 * by Pace Willisson (pace@blitz.com). The Rock Ridge Extension
7 * Support code is derived from software contributed to Berkeley
8 * by Atsushi Murai (amurai@spec.co.jp).
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 4. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * from: @(#)ufs_lookup.c 7.33 (Berkeley) 5/19/91
35 * @(#)cd9660_lookup.c 8.2 (Berkeley) 1/23/94
36 */
37
38#include <sys/cdefs.h>
| 1/*-
2 * Copyright (c) 1989, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley
6 * by Pace Willisson (pace@blitz.com). The Rock Ridge Extension
7 * Support code is derived from software contributed to Berkeley
8 * by Atsushi Murai (amurai@spec.co.jp).
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 4. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * from: @(#)ufs_lookup.c 7.33 (Berkeley) 5/19/91
35 * @(#)cd9660_lookup.c 8.2 (Berkeley) 1/23/94
36 */
37
38#include <sys/cdefs.h>
|
40
41#include <sys/param.h>
42#include <sys/systm.h>
43#include <sys/namei.h>
44#include <sys/bio.h>
45#include <sys/buf.h>
46#include <sys/vnode.h>
47#include <sys/mount.h>
48
49#include <isofs/cd9660/iso.h>
50#include <isofs/cd9660/cd9660_node.h>
51#include <isofs/cd9660/iso_rrip.h>
52
53/*
54 * Convert a component of a pathname into a pointer to a locked inode.
55 * This is a very central and rather complicated routine.
56 * If the filesystem is not maintained in a strict tree hierarchy,
57 * this can result in a deadlock situation (see comments in code below).
58 *
59 * The flag argument is LOOKUP, CREATE, RENAME, or DELETE depending on
60 * whether the name is to be looked up, created, renamed, or deleted.
61 * When CREATE, RENAME, or DELETE is specified, information usable in
62 * creating, renaming, or deleting a directory entry may be calculated.
63 * If flag has LOCKPARENT or'ed into it and the target of the pathname
64 * exists, lookup returns both the target and its parent directory locked.
65 * When creating or renaming and LOCKPARENT is specified, the target may
66 * not be ".". When deleting and LOCKPARENT is specified, the target may
67 * be "."., but the caller must check to ensure it does an vrele and iput
68 * instead of two iputs.
69 *
70 * Overall outline of ufs_lookup:
71 *
72 * search for name in directory, to found or notfound
73 * notfound:
74 * if creating, return locked directory, leaving info on available slots
75 * else return error
76 * found:
77 * if at end of path and deleting, return information to allow delete
78 * if at end of path and rewriting (RENAME and LOCKPARENT), lock target
79 * inode and return info to allow rewrite
80 * if not at end, add name to cache; if at end and neither creating
81 * nor deleting, add name to cache
82 *
83 * NOTE: (LOOKUP | LOCKPARENT) currently returns the parent inode unlocked.
84 */
85int
86cd9660_lookup(ap)
87 struct vop_cachedlookup_args /* {
88 struct vnode *a_dvp;
89 struct vnode **a_vpp;
90 struct componentname *a_cnp;
91 } */ *ap;
92{
93 struct vnode *vdp; /* vnode for directory being searched */
94 struct iso_node *dp; /* inode for directory being searched */
95 struct iso_mnt *imp; /* filesystem that directory is in */
96 struct buf *bp; /* a buffer of directory entries */
97 struct iso_directory_record *ep = 0;/* the current directory entry */
98 int entryoffsetinblock; /* offset of ep in bp's buffer */
99 int saveoffset = 0; /* offset of last directory entry in dir */
100 int numdirpasses; /* strategy for directory search */
101 doff_t endsearch; /* offset to end directory search */
102 struct vnode *pdp; /* saved dp during symlink work */
103 struct vnode *tdp; /* returned by cd9660_vget_internal */
104 u_long bmask; /* block offset mask */
105 int error;
106 ino_t ino = 0;
107 int reclen;
108 u_short namelen;
109 int isoflags;
110 char altname[NAME_MAX];
111 int res;
112 int assoc, len;
113 char *name;
114 struct vnode **vpp = ap->a_vpp;
115 struct componentname *cnp = ap->a_cnp;
116 int flags = cnp->cn_flags;
117 int nameiop = cnp->cn_nameiop;
118 struct thread *td = cnp->cn_thread;
119
120 bp = NULL;
121 *vpp = NULL;
122 vdp = ap->a_dvp;
123 dp = VTOI(vdp);
124 imp = dp->i_mnt;
125
126 /*
127 * We now have a segment name to search for, and a directory to search.
128 */
129
130 len = cnp->cn_namelen;
131 name = cnp->cn_nameptr;
132 /*
133 * A leading `=' means, we are looking for an associated file
134 */
135 if ((assoc = (imp->iso_ftype != ISO_FTYPE_RRIP && *name == ASSOCCHAR)))
136 {
137 len--;
138 name++;
139 }
140
141 /*
142 * If there is cached information on a previous search of
143 * this directory, pick up where we last left off.
144 * We cache only lookups as these are the most common
145 * and have the greatest payoff. Caching CREATE has little
146 * benefit as it usually must search the entire directory
147 * to determine that the entry does not exist. Caching the
148 * location of the last DELETE or RENAME has not reduced
149 * profiling time and hence has been removed in the interest
150 * of simplicity.
151 */
152 bmask = imp->im_bmask;
153 if (nameiop != LOOKUP || dp->i_diroff == 0 ||
154 dp->i_diroff > dp->i_size) {
155 entryoffsetinblock = 0;
156 dp->i_offset = 0;
157 numdirpasses = 1;
158 } else {
159 dp->i_offset = dp->i_diroff;
160 if ((entryoffsetinblock = dp->i_offset & bmask) &&
161 (error = cd9660_blkatoff(vdp, (off_t)dp->i_offset, NULL, &bp)))
162 return (error);
163 numdirpasses = 2;
164 nchstats.ncs_2passes++;
165 }
166 endsearch = dp->i_size;
167
168searchloop:
169 while (dp->i_offset < endsearch) {
170 /*
171 * If offset is on a block boundary,
172 * read the next directory block.
173 * Release previous if it exists.
174 */
175 if ((dp->i_offset & bmask) == 0) {
176 if (bp != NULL)
177 brelse(bp);
178 if ((error =
179 cd9660_blkatoff(vdp, (off_t)dp->i_offset, NULL, &bp)) != 0)
180 return (error);
181 entryoffsetinblock = 0;
182 }
183 /*
184 * Get pointer to next entry.
185 */
186 ep = (struct iso_directory_record *)
187 ((char *)bp->b_data + entryoffsetinblock);
188
189 reclen = isonum_711(ep->length);
190 if (reclen == 0) {
191 /* skip to next block, if any */
192 dp->i_offset =
193 (dp->i_offset & ~bmask) + imp->logical_block_size;
194 continue;
195 }
196
197 if (reclen < ISO_DIRECTORY_RECORD_SIZE)
198 /* illegal entry, stop */
199 break;
200
201 if (entryoffsetinblock + reclen > imp->logical_block_size)
202 /* entries are not allowed to cross boundaries */
203 break;
204
205 namelen = isonum_711(ep->name_len);
206 isoflags = isonum_711(imp->iso_ftype == ISO_FTYPE_HIGH_SIERRA?
207 &ep->date[6]: ep->flags);
208
209 if (reclen < ISO_DIRECTORY_RECORD_SIZE + namelen)
210 /* illegal entry, stop */
211 break;
212
213 /*
214 * Check for a name match.
215 */
216 switch (imp->iso_ftype) {
217 default:
218 if (!(isoflags & 4) == !assoc) {
219 if ((len == 1
220 && *name == '.')
221 || (flags & ISDOTDOT)) {
222 if (namelen == 1
223 && ep->name[0] == ((flags & ISDOTDOT) ? 1 : 0)) {
224 /*
225 * Save directory entry's inode number and
226 * release directory buffer.
227 */
228 dp->i_ino = isodirino(ep, imp);
229 goto found;
230 }
231 if (namelen != 1
232 || ep->name[0] != 0)
233 goto notfound;
234 } else if (!(res = isofncmp(name, len,
235 ep->name, namelen,
236 imp->joliet_level,
237 imp->im_flags,
238 imp->im_d2l,
239 imp->im_l2d))) {
240 if (isoflags & 2)
241 ino = isodirino(ep, imp);
242 else
243 ino = dbtob(bp->b_blkno)
244 + entryoffsetinblock;
245 saveoffset = dp->i_offset;
246 } else if (ino)
247 goto foundino;
248#ifdef NOSORTBUG /* On some CDs directory entries are not sorted correctly */
249 else if (res < 0)
250 goto notfound;
251 else if (res > 0 && numdirpasses == 2)
252 numdirpasses++;
253#endif
254 }
255 break;
256 case ISO_FTYPE_RRIP:
257 if (isonum_711(ep->flags)&2)
258 ino = isodirino(ep, imp);
259 else
260 ino = dbtob(bp->b_blkno) + entryoffsetinblock;
261 dp->i_ino = ino;
262 cd9660_rrip_getname(ep,altname,&namelen,&dp->i_ino,imp);
263 if (namelen == cnp->cn_namelen
264 && !bcmp(name,altname,namelen))
265 goto found;
266 ino = 0;
267 break;
268 }
269 dp->i_offset += reclen;
270 entryoffsetinblock += reclen;
271 }
272 if (ino) {
273foundino:
274 dp->i_ino = ino;
275 if (saveoffset != dp->i_offset) {
276 if (lblkno(imp, dp->i_offset) !=
277 lblkno(imp, saveoffset)) {
278 if (bp != NULL)
279 brelse(bp);
280 if ((error = cd9660_blkatoff(vdp,
281 (off_t)saveoffset, NULL, &bp)) != 0)
282 return (error);
283 }
284 entryoffsetinblock = saveoffset & bmask;
285 ep = (struct iso_directory_record *)
286 ((char *)bp->b_data + entryoffsetinblock);
287 dp->i_offset = saveoffset;
288 }
289 goto found;
290 }
291notfound:
292 /*
293 * If we started in the middle of the directory and failed
294 * to find our target, we must check the beginning as well.
295 */
296 if (numdirpasses == 2) {
297 numdirpasses--;
298 dp->i_offset = 0;
299 endsearch = dp->i_diroff;
300 goto searchloop;
301 }
302 if (bp != NULL)
303 brelse(bp);
304
305 /*
306 * Insert name into cache (as non-existent) if appropriate.
307 */
308 if (cnp->cn_flags & MAKEENTRY)
309 cache_enter(vdp, *vpp, cnp);
310 if (nameiop == CREATE || nameiop == RENAME)
311 return (EROFS);
312 return (ENOENT);
313
314found:
315 if (numdirpasses == 2)
316 nchstats.ncs_pass2++;
317
318 /*
319 * Found component in pathname.
320 * If the final component of path name, save information
321 * in the cache as to where the entry was found.
322 */
323 if ((flags & ISLASTCN) && nameiop == LOOKUP)
324 dp->i_diroff = dp->i_offset;
325
326 /*
327 * Step through the translation in the name. We do not `iput' the
328 * directory because we may need it again if a symbolic link
329 * is relative to the current directory. Instead we save it
330 * unlocked as "pdp". We must get the target inode before unlocking
331 * the directory to insure that the inode will not be removed
332 * before we get it. We prevent deadlock by always fetching
333 * inodes from the root, moving down the directory tree. Thus
334 * when following backward pointers ".." we must unlock the
335 * parent directory before getting the requested directory.
336 * There is a potential race condition here if both the current
337 * and parent directories are removed before the `iget' for the
338 * inode associated with ".." returns. We hope that this occurs
339 * infrequently since we cannot avoid this race condition without
340 * implementing a sophisticated deadlock detection algorithm.
341 * Note also that this simple deadlock detection scheme will not
342 * work if the filesystem has any hard links other than ".."
343 * that point backwards in the directory structure.
344 */
345 pdp = vdp;
346 /*
347 * If ino is different from dp->i_ino,
348 * it's a relocated directory.
349 */
350 if (flags & ISDOTDOT) {
351 VOP_UNLOCK(pdp, 0, td); /* race to get the inode */
352 error = cd9660_vget_internal(vdp->v_mount, dp->i_ino,
353 LK_EXCLUSIVE, &tdp,
354 dp->i_ino != ino, ep);
355 brelse(bp);
| 40
41#include <sys/param.h>
42#include <sys/systm.h>
43#include <sys/namei.h>
44#include <sys/bio.h>
45#include <sys/buf.h>
46#include <sys/vnode.h>
47#include <sys/mount.h>
48
49#include <isofs/cd9660/iso.h>
50#include <isofs/cd9660/cd9660_node.h>
51#include <isofs/cd9660/iso_rrip.h>
52
53/*
54 * Convert a component of a pathname into a pointer to a locked inode.
55 * This is a very central and rather complicated routine.
56 * If the filesystem is not maintained in a strict tree hierarchy,
57 * this can result in a deadlock situation (see comments in code below).
58 *
59 * The flag argument is LOOKUP, CREATE, RENAME, or DELETE depending on
60 * whether the name is to be looked up, created, renamed, or deleted.
61 * When CREATE, RENAME, or DELETE is specified, information usable in
62 * creating, renaming, or deleting a directory entry may be calculated.
63 * If flag has LOCKPARENT or'ed into it and the target of the pathname
64 * exists, lookup returns both the target and its parent directory locked.
65 * When creating or renaming and LOCKPARENT is specified, the target may
66 * not be ".". When deleting and LOCKPARENT is specified, the target may
67 * be "."., but the caller must check to ensure it does an vrele and iput
68 * instead of two iputs.
69 *
70 * Overall outline of ufs_lookup:
71 *
72 * search for name in directory, to found or notfound
73 * notfound:
74 * if creating, return locked directory, leaving info on available slots
75 * else return error
76 * found:
77 * if at end of path and deleting, return information to allow delete
78 * if at end of path and rewriting (RENAME and LOCKPARENT), lock target
79 * inode and return info to allow rewrite
80 * if not at end, add name to cache; if at end and neither creating
81 * nor deleting, add name to cache
82 *
83 * NOTE: (LOOKUP | LOCKPARENT) currently returns the parent inode unlocked.
84 */
85int
86cd9660_lookup(ap)
87 struct vop_cachedlookup_args /* {
88 struct vnode *a_dvp;
89 struct vnode **a_vpp;
90 struct componentname *a_cnp;
91 } */ *ap;
92{
93 struct vnode *vdp; /* vnode for directory being searched */
94 struct iso_node *dp; /* inode for directory being searched */
95 struct iso_mnt *imp; /* filesystem that directory is in */
96 struct buf *bp; /* a buffer of directory entries */
97 struct iso_directory_record *ep = 0;/* the current directory entry */
98 int entryoffsetinblock; /* offset of ep in bp's buffer */
99 int saveoffset = 0; /* offset of last directory entry in dir */
100 int numdirpasses; /* strategy for directory search */
101 doff_t endsearch; /* offset to end directory search */
102 struct vnode *pdp; /* saved dp during symlink work */
103 struct vnode *tdp; /* returned by cd9660_vget_internal */
104 u_long bmask; /* block offset mask */
105 int error;
106 ino_t ino = 0;
107 int reclen;
108 u_short namelen;
109 int isoflags;
110 char altname[NAME_MAX];
111 int res;
112 int assoc, len;
113 char *name;
114 struct vnode **vpp = ap->a_vpp;
115 struct componentname *cnp = ap->a_cnp;
116 int flags = cnp->cn_flags;
117 int nameiop = cnp->cn_nameiop;
118 struct thread *td = cnp->cn_thread;
119
120 bp = NULL;
121 *vpp = NULL;
122 vdp = ap->a_dvp;
123 dp = VTOI(vdp);
124 imp = dp->i_mnt;
125
126 /*
127 * We now have a segment name to search for, and a directory to search.
128 */
129
130 len = cnp->cn_namelen;
131 name = cnp->cn_nameptr;
132 /*
133 * A leading `=' means, we are looking for an associated file
134 */
135 if ((assoc = (imp->iso_ftype != ISO_FTYPE_RRIP && *name == ASSOCCHAR)))
136 {
137 len--;
138 name++;
139 }
140
141 /*
142 * If there is cached information on a previous search of
143 * this directory, pick up where we last left off.
144 * We cache only lookups as these are the most common
145 * and have the greatest payoff. Caching CREATE has little
146 * benefit as it usually must search the entire directory
147 * to determine that the entry does not exist. Caching the
148 * location of the last DELETE or RENAME has not reduced
149 * profiling time and hence has been removed in the interest
150 * of simplicity.
151 */
152 bmask = imp->im_bmask;
153 if (nameiop != LOOKUP || dp->i_diroff == 0 ||
154 dp->i_diroff > dp->i_size) {
155 entryoffsetinblock = 0;
156 dp->i_offset = 0;
157 numdirpasses = 1;
158 } else {
159 dp->i_offset = dp->i_diroff;
160 if ((entryoffsetinblock = dp->i_offset & bmask) &&
161 (error = cd9660_blkatoff(vdp, (off_t)dp->i_offset, NULL, &bp)))
162 return (error);
163 numdirpasses = 2;
164 nchstats.ncs_2passes++;
165 }
166 endsearch = dp->i_size;
167
168searchloop:
169 while (dp->i_offset < endsearch) {
170 /*
171 * If offset is on a block boundary,
172 * read the next directory block.
173 * Release previous if it exists.
174 */
175 if ((dp->i_offset & bmask) == 0) {
176 if (bp != NULL)
177 brelse(bp);
178 if ((error =
179 cd9660_blkatoff(vdp, (off_t)dp->i_offset, NULL, &bp)) != 0)
180 return (error);
181 entryoffsetinblock = 0;
182 }
183 /*
184 * Get pointer to next entry.
185 */
186 ep = (struct iso_directory_record *)
187 ((char *)bp->b_data + entryoffsetinblock);
188
189 reclen = isonum_711(ep->length);
190 if (reclen == 0) {
191 /* skip to next block, if any */
192 dp->i_offset =
193 (dp->i_offset & ~bmask) + imp->logical_block_size;
194 continue;
195 }
196
197 if (reclen < ISO_DIRECTORY_RECORD_SIZE)
198 /* illegal entry, stop */
199 break;
200
201 if (entryoffsetinblock + reclen > imp->logical_block_size)
202 /* entries are not allowed to cross boundaries */
203 break;
204
205 namelen = isonum_711(ep->name_len);
206 isoflags = isonum_711(imp->iso_ftype == ISO_FTYPE_HIGH_SIERRA?
207 &ep->date[6]: ep->flags);
208
209 if (reclen < ISO_DIRECTORY_RECORD_SIZE + namelen)
210 /* illegal entry, stop */
211 break;
212
213 /*
214 * Check for a name match.
215 */
216 switch (imp->iso_ftype) {
217 default:
218 if (!(isoflags & 4) == !assoc) {
219 if ((len == 1
220 && *name == '.')
221 || (flags & ISDOTDOT)) {
222 if (namelen == 1
223 && ep->name[0] == ((flags & ISDOTDOT) ? 1 : 0)) {
224 /*
225 * Save directory entry's inode number and
226 * release directory buffer.
227 */
228 dp->i_ino = isodirino(ep, imp);
229 goto found;
230 }
231 if (namelen != 1
232 || ep->name[0] != 0)
233 goto notfound;
234 } else if (!(res = isofncmp(name, len,
235 ep->name, namelen,
236 imp->joliet_level,
237 imp->im_flags,
238 imp->im_d2l,
239 imp->im_l2d))) {
240 if (isoflags & 2)
241 ino = isodirino(ep, imp);
242 else
243 ino = dbtob(bp->b_blkno)
244 + entryoffsetinblock;
245 saveoffset = dp->i_offset;
246 } else if (ino)
247 goto foundino;
248#ifdef NOSORTBUG /* On some CDs directory entries are not sorted correctly */
249 else if (res < 0)
250 goto notfound;
251 else if (res > 0 && numdirpasses == 2)
252 numdirpasses++;
253#endif
254 }
255 break;
256 case ISO_FTYPE_RRIP:
257 if (isonum_711(ep->flags)&2)
258 ino = isodirino(ep, imp);
259 else
260 ino = dbtob(bp->b_blkno) + entryoffsetinblock;
261 dp->i_ino = ino;
262 cd9660_rrip_getname(ep,altname,&namelen,&dp->i_ino,imp);
263 if (namelen == cnp->cn_namelen
264 && !bcmp(name,altname,namelen))
265 goto found;
266 ino = 0;
267 break;
268 }
269 dp->i_offset += reclen;
270 entryoffsetinblock += reclen;
271 }
272 if (ino) {
273foundino:
274 dp->i_ino = ino;
275 if (saveoffset != dp->i_offset) {
276 if (lblkno(imp, dp->i_offset) !=
277 lblkno(imp, saveoffset)) {
278 if (bp != NULL)
279 brelse(bp);
280 if ((error = cd9660_blkatoff(vdp,
281 (off_t)saveoffset, NULL, &bp)) != 0)
282 return (error);
283 }
284 entryoffsetinblock = saveoffset & bmask;
285 ep = (struct iso_directory_record *)
286 ((char *)bp->b_data + entryoffsetinblock);
287 dp->i_offset = saveoffset;
288 }
289 goto found;
290 }
291notfound:
292 /*
293 * If we started in the middle of the directory and failed
294 * to find our target, we must check the beginning as well.
295 */
296 if (numdirpasses == 2) {
297 numdirpasses--;
298 dp->i_offset = 0;
299 endsearch = dp->i_diroff;
300 goto searchloop;
301 }
302 if (bp != NULL)
303 brelse(bp);
304
305 /*
306 * Insert name into cache (as non-existent) if appropriate.
307 */
308 if (cnp->cn_flags & MAKEENTRY)
309 cache_enter(vdp, *vpp, cnp);
310 if (nameiop == CREATE || nameiop == RENAME)
311 return (EROFS);
312 return (ENOENT);
313
314found:
315 if (numdirpasses == 2)
316 nchstats.ncs_pass2++;
317
318 /*
319 * Found component in pathname.
320 * If the final component of path name, save information
321 * in the cache as to where the entry was found.
322 */
323 if ((flags & ISLASTCN) && nameiop == LOOKUP)
324 dp->i_diroff = dp->i_offset;
325
326 /*
327 * Step through the translation in the name. We do not `iput' the
328 * directory because we may need it again if a symbolic link
329 * is relative to the current directory. Instead we save it
330 * unlocked as "pdp". We must get the target inode before unlocking
331 * the directory to insure that the inode will not be removed
332 * before we get it. We prevent deadlock by always fetching
333 * inodes from the root, moving down the directory tree. Thus
334 * when following backward pointers ".." we must unlock the
335 * parent directory before getting the requested directory.
336 * There is a potential race condition here if both the current
337 * and parent directories are removed before the `iget' for the
338 * inode associated with ".." returns. We hope that this occurs
339 * infrequently since we cannot avoid this race condition without
340 * implementing a sophisticated deadlock detection algorithm.
341 * Note also that this simple deadlock detection scheme will not
342 * work if the filesystem has any hard links other than ".."
343 * that point backwards in the directory structure.
344 */
345 pdp = vdp;
346 /*
347 * If ino is different from dp->i_ino,
348 * it's a relocated directory.
349 */
350 if (flags & ISDOTDOT) {
351 VOP_UNLOCK(pdp, 0, td); /* race to get the inode */
352 error = cd9660_vget_internal(vdp->v_mount, dp->i_ino,
353 LK_EXCLUSIVE, &tdp,
354 dp->i_ino != ino, ep);
355 brelse(bp);
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360 *vpp = tdp;
361 } else if (dp->i_number == dp->i_ino) {
362 brelse(bp);
363 VREF(vdp); /* we want ourself, ie "." */
364 *vpp = vdp;
365 } else {
366 error = cd9660_vget_internal(vdp->v_mount, dp->i_ino,
367 LK_EXCLUSIVE, &tdp,
368 dp->i_ino != ino, ep);
369 brelse(bp);
370 if (error)
371 return (error);
372 *vpp = tdp;
373 }
374
375 /*
376 * Insert name into cache if appropriate.
377 */
378 if (cnp->cn_flags & MAKEENTRY)
379 cache_enter(vdp, *vpp, cnp);
380 return (0);
381}
382
383/*
384 * Return buffer with the contents of block "offset" from the beginning of
385 * directory "ip". If "res" is non-zero, fill it in with a pointer to the
386 * remaining space in the directory.
387 */
388int
389cd9660_blkatoff(vp, offset, res, bpp)
390 struct vnode *vp;
391 off_t offset;
392 char **res;
393 struct buf **bpp;
394{
395 struct iso_node *ip;
396 struct iso_mnt *imp;
397 struct buf *bp;
398 daddr_t lbn;
399 int bsize, bshift, error;
400
401 ip = VTOI(vp);
402 imp = ip->i_mnt;
403 lbn = lblkno(imp, offset);
404 bsize = blksize(imp, ip, lbn);
405 bshift = imp->im_bshift;
406
407 if ((error = bread(vp, lbn, bsize, NOCRED, &bp)) != 0) {
408 brelse(bp);
409 *bpp = NULL;
410 return (error);
411 }
412
413 /*
414 * We must BMAP the buffer because the directory code may use b_blkno
415 * to calculate the inode for certain types of directory entries.
416 * We could get away with not doing it before we VMIO-backed the
417 * directories because the buffers would get freed atomically with
418 * the invalidation of their data. But with VMIO-backed buffers
419 * the buffers may be freed and then later reconstituted - and the
420 * reconstituted buffer will have no knowledge of b_blkno.
421 */
422 if (bp->b_blkno == bp->b_lblkno) {
423 bp->b_blkno = (ip->iso_start + bp->b_lblkno) << (bshift - DEV_BSHIFT);
424 }
425
426 if (res)
427 *res = (char *)bp->b_data + blkoff(imp, offset);
428 *bpp = bp;
429 return (0);
430}
| 359 *vpp = tdp;
360 } else if (dp->i_number == dp->i_ino) {
361 brelse(bp);
362 VREF(vdp); /* we want ourself, ie "." */
363 *vpp = vdp;
364 } else {
365 error = cd9660_vget_internal(vdp->v_mount, dp->i_ino,
366 LK_EXCLUSIVE, &tdp,
367 dp->i_ino != ino, ep);
368 brelse(bp);
369 if (error)
370 return (error);
371 *vpp = tdp;
372 }
373
374 /*
375 * Insert name into cache if appropriate.
376 */
377 if (cnp->cn_flags & MAKEENTRY)
378 cache_enter(vdp, *vpp, cnp);
379 return (0);
380}
381
382/*
383 * Return buffer with the contents of block "offset" from the beginning of
384 * directory "ip". If "res" is non-zero, fill it in with a pointer to the
385 * remaining space in the directory.
386 */
387int
388cd9660_blkatoff(vp, offset, res, bpp)
389 struct vnode *vp;
390 off_t offset;
391 char **res;
392 struct buf **bpp;
393{
394 struct iso_node *ip;
395 struct iso_mnt *imp;
396 struct buf *bp;
397 daddr_t lbn;
398 int bsize, bshift, error;
399
400 ip = VTOI(vp);
401 imp = ip->i_mnt;
402 lbn = lblkno(imp, offset);
403 bsize = blksize(imp, ip, lbn);
404 bshift = imp->im_bshift;
405
406 if ((error = bread(vp, lbn, bsize, NOCRED, &bp)) != 0) {
407 brelse(bp);
408 *bpp = NULL;
409 return (error);
410 }
411
412 /*
413 * We must BMAP the buffer because the directory code may use b_blkno
414 * to calculate the inode for certain types of directory entries.
415 * We could get away with not doing it before we VMIO-backed the
416 * directories because the buffers would get freed atomically with
417 * the invalidation of their data. But with VMIO-backed buffers
418 * the buffers may be freed and then later reconstituted - and the
419 * reconstituted buffer will have no knowledge of b_blkno.
420 */
421 if (bp->b_blkno == bp->b_lblkno) {
422 bp->b_blkno = (ip->iso_start + bp->b_lblkno) << (bshift - DEV_BSHIFT);
423 }
424
425 if (res)
426 *res = (char *)bp->b_data + blkoff(imp, offset);
427 *bpp = bp;
428 return (0);
429}
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