Annotation of src/sys/ufs/ufs/ufs_lookup.c, Revision 1.132.4.1
1.132.4.1! skrll 1: /* $NetBSD: ufs_lookup.c,v 1.134 2015/03/28 17:23:42 maxv Exp $ */
1.2 cgd 2:
1.1 mycroft 3: /*
4: * Copyright (c) 1989, 1993
5: * The Regents of the University of California. All rights reserved.
6: * (c) UNIX System Laboratories, Inc.
7: * All or some portions of this file are derived from material licensed
8: * to the University of California by American Telephone and Telegraph
9: * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10: * the permission of UNIX System Laboratories, Inc.
11: *
12: * Redistribution and use in source and binary forms, with or without
13: * modification, are permitted provided that the following conditions
14: * are met:
15: * 1. Redistributions of source code must retain the above copyright
16: * notice, this list of conditions and the following disclaimer.
17: * 2. Redistributions in binary form must reproduce the above copyright
18: * notice, this list of conditions and the following disclaimer in the
19: * documentation and/or other materials provided with the distribution.
1.50 agc 20: * 3. Neither the name of the University nor the names of its contributors
1.1 mycroft 21: * may be used to endorse or promote products derived from this software
22: * without specific prior written permission.
23: *
24: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34: * SUCH DAMAGE.
35: *
1.3 mycroft 36: * @(#)ufs_lookup.c 8.9 (Berkeley) 8/11/94
1.1 mycroft 37: */
1.35 lukem 38:
39: #include <sys/cdefs.h>
1.132.4.1! skrll 40: __KERNEL_RCSID(0, "$NetBSD: ufs_lookup.c,v 1.134 2015/03/28 17:23:42 maxv Exp $");
1.65 thorpej 41:
42: #ifdef _KERNEL_OPT
43: #include "opt_ffs.h"
44: #endif
1.1 mycroft 45:
46: #include <sys/param.h>
1.7 christos 47: #include <sys/systm.h>
1.1 mycroft 48: #include <sys/namei.h>
49: #include <sys/buf.h>
50: #include <sys/file.h>
1.27 fvdl 51: #include <sys/stat.h>
1.1 mycroft 52: #include <sys/mount.h>
53: #include <sys/vnode.h>
1.27 fvdl 54: #include <sys/kernel.h>
1.76 elad 55: #include <sys/kauth.h>
1.99 simonb 56: #include <sys/wapbl.h>
1.83 hannken 57: #include <sys/fstrans.h>
1.94 ad 58: #include <sys/proc.h>
1.92 pooka 59: #include <sys/kmem.h>
1.1 mycroft 60:
61: #include <ufs/ufs/inode.h>
62: #include <ufs/ufs/dir.h>
1.61 rumble 63: #ifdef UFS_DIRHASH
64: #include <ufs/ufs/dirhash.h>
65: #endif
1.1 mycroft 66: #include <ufs/ufs/ufsmount.h>
67: #include <ufs/ufs/ufs_extern.h>
1.15 bouyer 68: #include <ufs/ufs/ufs_bswap.h>
1.99 simonb 69: #include <ufs/ufs/ufs_wapbl.h>
1.1 mycroft 70:
1.112 elad 71: #include <miscfs/genfs/genfs.h>
72:
1.1 mycroft 73: #ifdef DIAGNOSTIC
74: int dirchk = 1;
75: #else
76: int dirchk = 0;
77: #endif
78:
79: /*
80: * Convert a component of a pathname into a pointer to a locked inode.
81: * This is a very central and rather complicated routine.
82: * If the file system is not maintained in a strict tree hierarchy,
83: * this can result in a deadlock situation (see comments in code below).
84: *
85: * The cnp->cn_nameiop argument is LOOKUP, CREATE, RENAME, or DELETE depending
86: * on whether the name is to be looked up, created, renamed, or deleted.
87: * When CREATE, RENAME, or DELETE is specified, information usable in
88: * creating, renaming, or deleting a directory entry may be calculated.
89: * If flag has LOCKPARENT or'ed into it and the target of the pathname
90: * exists, lookup returns both the target and its parent directory locked.
91: * When creating or renaming and LOCKPARENT is specified, the target may
92: * not be ".". When deleting and LOCKPARENT is specified, the target may
93: * be "."., but the caller must check to ensure it does an vrele and vput
94: * instead of two vputs.
95: *
96: * Overall outline of ufs_lookup:
97: *
98: * check accessibility of directory
99: * look for name in cache, if found, then if at end of path
100: * and deleting or creating, drop it, else return name
101: * search for name in directory, to found or notfound
102: * notfound:
103: * if creating, return locked directory, leaving info on available slots
104: * else return error
105: * found:
106: * if at end of path and deleting, return information to allow delete
107: * if at end of path and rewriting (RENAME and LOCKPARENT), lock target
108: * inode and return info to allow rewrite
109: * if not at end, add name to cache; if at end and neither creating
110: * nor deleting, add name to cache
111: */
112: int
1.64 thorpej 113: ufs_lookup(void *v)
1.7 christos 114: {
1.129 hannken 115: struct vop_lookup_v2_args /* {
1.1 mycroft 116: struct vnode *a_dvp;
117: struct vnode **a_vpp;
118: struct componentname *a_cnp;
1.7 christos 119: } */ *ap = v;
1.58 mycroft 120: struct vnode *vdp = ap->a_dvp; /* vnode for directory being searched */
121: struct inode *dp = VTOI(vdp); /* inode for directory being searched */
1.1 mycroft 122: struct buf *bp; /* a buffer of directory entries */
1.30 augustss 123: struct direct *ep; /* the current directory entry */
1.1 mycroft 124: int entryoffsetinblock; /* offset of ep in bp's buffer */
1.114 yamt 125: enum {
126: NONE, /* need to search a slot for our new entry */
127: COMPACT, /* a compaction can make a slot in the current
128: DIRBLKSIZ block */
129: FOUND, /* found a slot (or no need to search) */
130: } slotstatus;
131: doff_t slotoffset; /* offset of area with free space.
132: a special value -1 for invalid */
1.1 mycroft 133: int slotsize; /* size of area at slotoffset */
1.114 yamt 134: int slotfreespace; /* accumulated amount of space free in
135: the current DIRBLKSIZ block */
1.1 mycroft 136: int slotneeded; /* size of the entry we're seeking */
137: int numdirpasses; /* strategy for directory search */
138: doff_t endsearch; /* offset to end directory search */
1.114 yamt 139: doff_t prevoff; /* previous value of ulr_offset */
1.130 hannken 140: struct vnode *tdp; /* returned by vcache_get */
1.114 yamt 141: doff_t enduseful; /* pointer past last used dir slot.
142: used for directory truncation. */
1.1 mycroft 143: u_long bmask; /* block offset mask */
1.114 yamt 144: int error;
1.1 mycroft 145: struct vnode **vpp = ap->a_vpp;
146: struct componentname *cnp = ap->a_cnp;
1.76 elad 147: kauth_cred_t cred = cnp->cn_cred;
1.21 wrstuden 148: int flags;
1.1 mycroft 149: int nameiop = cnp->cn_nameiop;
1.58 mycroft 150: struct ufsmount *ump = dp->i_ump;
151: const int needswap = UFS_MPNEEDSWAP(ump);
152: int dirblksiz = ump->um_dirblksiz;
1.42 yamt 153: ino_t foundino;
1.108 dholland 154: struct ufs_lookup_results *results;
1.119 dholland 155: int iswhiteout; /* temp result from cache_lookup() */
1.1 mycroft 156:
1.21 wrstuden 157: flags = cnp->cn_flags;
158:
1.1 mycroft 159: bp = NULL;
160: slotoffset = -1;
161: *vpp = NULL;
1.61 rumble 162: endsearch = 0; /* silence compiler warning */
1.108 dholland 163:
164: /*
165: * Produce the auxiliary lookup results into i_crap. Increment
166: * its serial number so elsewhere we can tell if we're using
167: * stale results. This should not be done this way. XXX.
168: */
169: results = &dp->i_crap;
170: dp->i_crapcounter++;
171:
1.1 mycroft 172: /*
173: * Check accessiblity of directory.
174: */
1.95 pooka 175: if ((error = VOP_ACCESS(vdp, VEXEC, cred)) != 0)
1.1 mycroft 176: return (error);
177:
1.14 fvdl 178: if ((flags & ISLASTCN) && (vdp->v_mount->mnt_flag & MNT_RDONLY) &&
1.99 simonb 179: (nameiop == DELETE || nameiop == RENAME))
1.14 fvdl 180: return (EROFS);
181:
1.1 mycroft 182: /*
183: * We now have a segment name to search for, and a directory to search.
184: *
185: * Before tediously performing a linear scan of the directory,
186: * check the name cache to see if the directory/name pair
187: * we are looking for is known already.
188: */
1.120 dholland 189: if (cache_lookup(vdp, cnp->cn_nameptr, cnp->cn_namelen,
190: cnp->cn_nameiop, cnp->cn_flags, &iswhiteout, vpp)) {
1.119 dholland 191: if (iswhiteout) {
192: cnp->cn_flags |= ISWHITEOUT;
193: }
194: return *vpp == NULLVP ? ENOENT : 0;
195: }
196: if (iswhiteout) {
197: /*
198: * The namecache set iswhiteout without finding a
199: * cache entry. As of this writing (20121014), this
200: * can happen if there was a whiteout entry that has
201: * been invalidated by the lookup. It is not clear if
202: * it is correct to set ISWHITEOUT in this case or
203: * not; however, doing so retains the prior behavior,
204: * so we'll go with that until some clearer answer
205: * appears. XXX
206: */
207: cnp->cn_flags |= ISWHITEOUT;
1.81 chs 208: }
1.1 mycroft 209:
1.89 hannken 210: fstrans_start(vdp->v_mount, FSTRANS_SHARED);
1.83 hannken 211:
1.1 mycroft 212: /*
213: * Suppress search for slots unless creating
214: * file and at end of pathname, in which case
215: * we watch for a place to put the new file in
216: * case it doesn't already exist.
217: */
218: slotstatus = FOUND;
219: slotfreespace = slotsize = slotneeded = 0;
1.114 yamt 220: if ((nameiop == CREATE || nameiop == RENAME) && (flags & ISLASTCN)) {
1.1 mycroft 221: slotstatus = NONE;
1.123 dholland 222: slotneeded = UFS_DIRECTSIZ(cnp->cn_namelen);
1.1 mycroft 223: }
224:
225: /*
226: * If there is cached information on a previous search of
227: * this directory, pick up where we last left off.
228: * We cache only lookups as these are the most common
229: * and have the greatest payoff. Caching CREATE has little
230: * benefit as it usually must search the entire directory
231: * to determine that the entry does not exist. Caching the
232: * location of the last DELETE or RENAME has not reduced
233: * profiling time and hence has been removed in the interest
234: * of simplicity.
235: */
1.54 dbj 236: bmask = vdp->v_mount->mnt_stat.f_iosize - 1;
1.61 rumble 237:
238: #ifdef UFS_DIRHASH
239: /*
240: * Use dirhash for fast operations on large directories. The logic
241: * to determine whether to hash the directory is contained within
242: * ufsdirhash_build(); a zero return means that it decided to hash
243: * this directory and it successfully built up the hash table.
244: */
245: if (ufsdirhash_build(dp) == 0) {
246: /* Look for a free slot if needed. */
247: enduseful = dp->i_size;
248: if (slotstatus != FOUND) {
249: slotoffset = ufsdirhash_findfree(dp, slotneeded,
250: &slotsize);
251: if (slotoffset >= 0) {
252: slotstatus = COMPACT;
253: enduseful = ufsdirhash_enduseful(dp);
254: if (enduseful < 0)
255: enduseful = dp->i_size;
256: }
257: }
258: /* Look up the component. */
259: numdirpasses = 1;
260: entryoffsetinblock = 0; /* silence compiler warning */
261: switch (ufsdirhash_lookup(dp, cnp->cn_nameptr, cnp->cn_namelen,
1.108 dholland 262: &results->ulr_offset, &bp, nameiop == DELETE ? &prevoff : NULL)) {
1.61 rumble 263: case 0:
264: ep = (struct direct *)((char *)bp->b_data +
1.108 dholland 265: (results->ulr_offset & bmask));
1.61 rumble 266: goto foundentry;
267: case ENOENT:
1.108 dholland 268: results->ulr_offset = roundup(dp->i_size, dirblksiz);
1.61 rumble 269: goto notfound;
270: default:
271: /* Something failed; just do a linear search. */
272: break;
273: }
274: }
275: #endif /* UFS_DIRHASH */
276:
1.108 dholland 277: if (nameiop != LOOKUP || results->ulr_diroff == 0 ||
278: results->ulr_diroff >= dp->i_size) {
1.1 mycroft 279: entryoffsetinblock = 0;
1.108 dholland 280: results->ulr_offset = 0;
1.1 mycroft 281: numdirpasses = 1;
282: } else {
1.108 dholland 283: results->ulr_offset = results->ulr_diroff;
284: if ((entryoffsetinblock = results->ulr_offset & bmask) &&
285: (error = ufs_blkatoff(vdp, (off_t)results->ulr_offset,
1.97 hannken 286: NULL, &bp, false)))
1.83 hannken 287: goto out;
1.1 mycroft 288: numdirpasses = 2;
1.132 joerg 289: namecache_count_2passes();
1.1 mycroft 290: }
1.108 dholland 291: prevoff = results->ulr_offset;
1.43 fvdl 292: endsearch = roundup(dp->i_size, dirblksiz);
1.1 mycroft 293: enduseful = 0;
294:
295: searchloop:
1.108 dholland 296: while (results->ulr_offset < endsearch) {
1.48 yamt 297: if (curcpu()->ci_schedstate.spc_flags & SPCF_SHOULDYIELD)
1.87 ad 298: preempt();
1.1 mycroft 299: /*
300: * If necessary, get the next directory block.
301: */
1.108 dholland 302: if ((results->ulr_offset & bmask) == 0) {
1.1 mycroft 303: if (bp != NULL)
1.93 ad 304: brelse(bp, 0);
1.114 yamt 305: error = ufs_blkatoff(vdp, (off_t)results->ulr_offset,
306: NULL, &bp, false);
1.7 christos 307: if (error)
1.83 hannken 308: goto out;
1.1 mycroft 309: entryoffsetinblock = 0;
310: }
311: /*
1.91 pooka 312: * If still looking for a slot, and at a DIRBLKSIZ
1.1 mycroft 313: * boundary, have to start looking for free space again.
314: */
315: if (slotstatus == NONE &&
1.40 dbj 316: (entryoffsetinblock & (dirblksiz - 1)) == 0) {
1.1 mycroft 317: slotoffset = -1;
318: slotfreespace = 0;
319: }
320: /*
321: * Get pointer to next entry.
322: * Full validation checks are slow, so we only check
323: * enough to insure forward progress through the
324: * directory. Complete checks can be run by patching
325: * "dirchk" to be true.
326: */
1.75 christos 327: KASSERT(bp != NULL);
1.1 mycroft 328: ep = (struct direct *)((char *)bp->b_data + entryoffsetinblock);
329: if (ep->d_reclen == 0 ||
1.7 christos 330: (dirchk && ufs_dirbadentry(vdp, ep, entryoffsetinblock))) {
1.1 mycroft 331: int i;
332:
1.108 dholland 333: ufs_dirbad(dp, results->ulr_offset, "mangled entry");
1.40 dbj 334: i = dirblksiz - (entryoffsetinblock & (dirblksiz - 1));
1.108 dholland 335: results->ulr_offset += i;
1.1 mycroft 336: entryoffsetinblock += i;
337: continue;
338: }
339:
340: /*
341: * If an appropriate sized slot has not yet been found,
342: * check to see if one is available. Also accumulate space
343: * in the current block so that we can determine if
344: * compaction is viable.
345: */
346: if (slotstatus != FOUND) {
1.15 bouyer 347: int size = ufs_rw16(ep->d_reclen, needswap);
1.1 mycroft 348:
349: if (ep->d_ino != 0)
1.123 dholland 350: size -= UFS_DIRSIZ(FSFMT(vdp), ep, needswap);
1.1 mycroft 351: if (size > 0) {
352: if (size >= slotneeded) {
353: slotstatus = FOUND;
1.108 dholland 354: slotoffset = results->ulr_offset;
1.15 bouyer 355: slotsize = ufs_rw16(ep->d_reclen,
1.58 mycroft 356: needswap);
1.1 mycroft 357: } else if (slotstatus == NONE) {
358: slotfreespace += size;
359: if (slotoffset == -1)
1.108 dholland 360: slotoffset = results->ulr_offset;
1.1 mycroft 361: if (slotfreespace >= slotneeded) {
362: slotstatus = COMPACT;
1.108 dholland 363: slotsize = results->ulr_offset +
1.16 kleink 364: ufs_rw16(ep->d_reclen,
1.58 mycroft 365: needswap) -
366: slotoffset;
1.1 mycroft 367: }
368: }
369: }
370: }
371:
372: /*
373: * Check for a name match.
374: */
375: if (ep->d_ino) {
1.114 yamt 376: int namlen;
377:
1.15 bouyer 378: #if (BYTE_ORDER == LITTLE_ENDIAN)
1.58 mycroft 379: if (FSFMT(vdp) && needswap == 0)
380: namlen = ep->d_type;
381: else
1.52 yamt 382: namlen = ep->d_namlen;
1.15 bouyer 383: #else
1.62 perry 384: if (FSFMT(vdp) && needswap != 0)
1.52 yamt 385: namlen = ep->d_type;
386: else
1.1 mycroft 387: namlen = ep->d_namlen;
1.15 bouyer 388: #endif
1.1 mycroft 389: if (namlen == cnp->cn_namelen &&
1.18 perry 390: !memcmp(cnp->cn_nameptr, ep->d_name,
1.58 mycroft 391: (unsigned)namlen)) {
1.61 rumble 392: #ifdef UFS_DIRHASH
393: foundentry:
394: #endif
1.1 mycroft 395: /*
396: * Save directory entry's inode number and
1.114 yamt 397: * reclen, and release directory buffer.
1.1 mycroft 398: */
1.58 mycroft 399: if (!FSFMT(vdp) && ep->d_type == DT_WHT) {
1.3 mycroft 400: slotstatus = FOUND;
1.108 dholland 401: slotoffset = results->ulr_offset;
1.16 kleink 402: slotsize = ufs_rw16(ep->d_reclen,
403: needswap);
1.108 dholland 404: results->ulr_reclen = slotsize;
1.6 mycroft 405: /*
1.114 yamt 406: * This is used to set
407: * results->ulr_endoff,
408: * which may be used by ufs_direnter()
1.6 mycroft 409: * as a length to truncate the
410: * directory to. Therefore, it must
411: * point past the end of the last
412: * non-empty directory entry. We don't
413: * know where that is in this case, so
414: * we effectively disable shrinking by
415: * using the existing size of the
416: * directory.
417: *
418: * Note that we wouldn't expect to
419: * shrink the directory while rewriting
420: * an existing entry anyway.
421: */
422: enduseful = endsearch;
1.114 yamt 423: cnp->cn_flags |= ISWHITEOUT;
1.3 mycroft 424: numdirpasses--;
425: goto notfound;
426: }
1.42 yamt 427: foundino = ufs_rw32(ep->d_ino, needswap);
1.114 yamt 428: results->ulr_reclen =
429: ufs_rw16(ep->d_reclen, needswap);
1.1 mycroft 430: goto found;
431: }
432: }
1.108 dholland 433: prevoff = results->ulr_offset;
434: results->ulr_offset += ufs_rw16(ep->d_reclen, needswap);
1.15 bouyer 435: entryoffsetinblock += ufs_rw16(ep->d_reclen, needswap);
1.1 mycroft 436: if (ep->d_ino)
1.108 dholland 437: enduseful = results->ulr_offset;
1.1 mycroft 438: }
1.3 mycroft 439: notfound:
1.1 mycroft 440: /*
441: * If we started in the middle of the directory and failed
442: * to find our target, we must check the beginning as well.
443: */
444: if (numdirpasses == 2) {
445: numdirpasses--;
1.108 dholland 446: results->ulr_offset = 0;
447: endsearch = results->ulr_diroff;
1.1 mycroft 448: goto searchloop;
449: }
450: if (bp != NULL)
1.93 ad 451: brelse(bp, 0);
1.1 mycroft 452: /*
453: * If creating, and at end of pathname and current
454: * directory has not been removed, then can consider
455: * allowing file to be created.
456: */
1.3 mycroft 457: if ((nameiop == CREATE || nameiop == RENAME ||
458: (nameiop == DELETE &&
1.114 yamt 459: (cnp->cn_flags & DOWHITEOUT) &&
460: (cnp->cn_flags & ISWHITEOUT))) &&
1.101 ad 461: (flags & ISLASTCN) && dp->i_nlink != 0) {
1.12 kleink 462: /*
1.1 mycroft 463: * Access for write is interpreted as allowing
464: * creation of files in the directory.
465: */
1.95 pooka 466: error = VOP_ACCESS(vdp, VWRITE, cred);
1.7 christos 467: if (error)
1.83 hannken 468: goto out;
1.1 mycroft 469: /*
470: * Return an indication of where the new directory
471: * entry should be put. If we didn't find a slot,
1.108 dholland 472: * then set results->ulr_count to 0 indicating
1.1 mycroft 473: * that the new slot belongs at the end of the
474: * directory. If we found a slot, then the new entry
1.108 dholland 475: * can be put in the range from results->ulr_offset to
476: * results->ulr_offset + results->ulr_count.
1.1 mycroft 477: */
478: if (slotstatus == NONE) {
1.108 dholland 479: results->ulr_offset = roundup(dp->i_size, dirblksiz);
480: results->ulr_count = 0;
481: enduseful = results->ulr_offset;
1.3 mycroft 482: } else if (nameiop == DELETE) {
1.108 dholland 483: results->ulr_offset = slotoffset;
484: if ((results->ulr_offset & (dirblksiz - 1)) == 0)
485: results->ulr_count = 0;
1.3 mycroft 486: else
1.114 yamt 487: results->ulr_count =
488: results->ulr_offset - prevoff;
1.1 mycroft 489: } else {
1.108 dholland 490: results->ulr_offset = slotoffset;
491: results->ulr_count = slotsize;
1.1 mycroft 492: if (enduseful < slotoffset + slotsize)
493: enduseful = slotoffset + slotsize;
494: }
1.108 dholland 495: results->ulr_endoff = roundup(enduseful, dirblksiz);
1.54 dbj 496: #if 0 /* commented out by dbj. none of the on disk fields changed */
1.1 mycroft 497: dp->i_flag |= IN_CHANGE | IN_UPDATE;
1.54 dbj 498: #endif
1.1 mycroft 499: /*
500: * We return with the directory locked, so that
501: * the parameters we set up above will still be
502: * valid if we actually decide to do a direnter().
503: * We return ni_vp == NULL to indicate that the entry
504: * does not currently exist; we leave a pointer to
505: * the (locked) directory inode in ndp->ni_dvp.
506: *
507: * NB - if the directory is unlocked, then this
508: * information cannot be used.
509: */
1.83 hannken 510: error = EJUSTRETURN;
511: goto out;
1.1 mycroft 512: }
513: /*
514: * Insert name into cache (as non-existent) if appropriate.
515: */
1.117 rmind 516: if (nameiop != CREATE) {
1.120 dholland 517: cache_enter(vdp, *vpp, cnp->cn_nameptr, cnp->cn_namelen,
518: cnp->cn_flags);
1.117 rmind 519: }
1.83 hannken 520: error = ENOENT;
521: goto out;
1.1 mycroft 522:
523: found:
524: if (numdirpasses == 2)
1.132 joerg 525: namecache_count_pass2();
1.1 mycroft 526: /*
527: * Check that directory length properly reflects presence
528: * of this entry.
529: */
1.123 dholland 530: if (results->ulr_offset + UFS_DIRSIZ(FSFMT(vdp), ep, needswap) > dp->i_size) {
1.108 dholland 531: ufs_dirbad(dp, results->ulr_offset, "i_size too small");
1.114 yamt 532: dp->i_size =
1.123 dholland 533: results->ulr_offset + UFS_DIRSIZ(FSFMT(vdp), ep, needswap);
1.44 kristerw 534: DIP_ASSIGN(dp, size, dp->i_size);
1.1 mycroft 535: dp->i_flag |= IN_CHANGE | IN_UPDATE;
1.99 simonb 536: UFS_WAPBL_UPDATE(vdp, NULL, NULL, UPDATE_DIROP);
1.1 mycroft 537: }
1.93 ad 538: brelse(bp, 0);
1.1 mycroft 539:
540: /*
541: * Found component in pathname.
542: * If the final component of path name, save information
543: * in the cache as to where the entry was found.
544: */
545: if ((flags & ISLASTCN) && nameiop == LOOKUP)
1.108 dholland 546: results->ulr_diroff = results->ulr_offset &~ (dirblksiz - 1);
1.1 mycroft 547:
548: /*
549: * If deleting, and at end of pathname, return
550: * parameters which can be used to remove file.
1.81 chs 551: * Lock the inode, being careful with ".".
1.1 mycroft 552: */
553: if (nameiop == DELETE && (flags & ISLASTCN)) {
554: /*
1.108 dholland 555: * Return pointer to current entry in results->ulr_offset,
1.1 mycroft 556: * and distance past previous entry (if there
1.108 dholland 557: * is a previous entry in this block) in results->ulr_count.
1.1 mycroft 558: * Save directory inode pointer in ndp->ni_dvp for dirremove().
559: */
1.108 dholland 560: if ((results->ulr_offset & (dirblksiz - 1)) == 0)
561: results->ulr_count = 0;
1.1 mycroft 562: else
1.108 dholland 563: results->ulr_count = results->ulr_offset - prevoff;
1.113 hannken 564: if (dp->i_number == foundino) {
565: vref(vdp);
566: tdp = vdp;
567: } else {
1.130 hannken 568: error = vcache_get(vdp->v_mount,
569: &foundino, sizeof(foundino), &tdp);
1.113 hannken 570: if (error)
571: goto out;
572: }
1.1 mycroft 573: /*
1.112 elad 574: * Write access to directory required to delete files.
575: */
576: error = VOP_ACCESS(vdp, VWRITE, cred);
577: if (error) {
1.130 hannken 578: vrele(tdp);
1.112 elad 579: goto out;
580: }
581: /*
1.1 mycroft 582: * If directory is "sticky", then user must own
583: * the directory, or the file in it, else she
584: * may not delete it (unless she's root). This
585: * implements append-only directories.
586: */
1.112 elad 587: if (dp->i_mode & ISVTX) {
588: error = kauth_authorize_vnode(cred, KAUTH_VNODE_DELETE,
589: tdp, vdp, genfs_can_sticky(cred, dp->i_uid,
590: VTOI(tdp)->i_uid));
591: if (error) {
1.130 hannken 592: vrele(tdp);
1.112 elad 593: error = EPERM;
594: goto out;
595: }
596: }
1.1 mycroft 597: *vpp = tdp;
1.83 hannken 598: error = 0;
599: goto out;
1.1 mycroft 600: }
601:
602: /*
603: * If rewriting (RENAME), return the inode and the
604: * information required to rewrite the present directory
605: * Must get inode of directory entry to verify it's a
606: * regular file, or empty directory.
607: */
1.81 chs 608: if (nameiop == RENAME && (flags & ISLASTCN)) {
1.95 pooka 609: error = VOP_ACCESS(vdp, VWRITE, cred);
1.7 christos 610: if (error)
1.83 hannken 611: goto out;
1.1 mycroft 612: /*
613: * Careful about locking second inode.
614: * This can only occur if the target is ".".
615: */
1.83 hannken 616: if (dp->i_number == foundino) {
617: error = EISDIR;
618: goto out;
619: }
1.130 hannken 620: error = vcache_get(vdp->v_mount,
621: &foundino, sizeof(foundino), &tdp);
1.7 christos 622: if (error)
1.83 hannken 623: goto out;
1.1 mycroft 624: *vpp = tdp;
1.83 hannken 625: error = 0;
626: goto out;
1.1 mycroft 627: }
628:
1.130 hannken 629: if (dp->i_number == foundino) {
1.103 pooka 630: vref(vdp); /* we want ourself, ie "." */
1.1 mycroft 631: *vpp = vdp;
632: } else {
1.130 hannken 633: error = vcache_get(vdp->v_mount,
634: &foundino, sizeof(foundino), &tdp);
1.7 christos 635: if (error)
1.83 hannken 636: goto out;
1.1 mycroft 637: *vpp = tdp;
638: }
639:
640: /*
641: * Insert name into cache if appropriate.
642: */
1.120 dholland 643: cache_enter(vdp, *vpp, cnp->cn_nameptr, cnp->cn_namelen, cnp->cn_flags);
1.83 hannken 644: error = 0;
645:
646: out:
647: fstrans_done(vdp->v_mount);
648: return error;
1.1 mycroft 649: }
650:
651: void
1.64 thorpej 652: ufs_dirbad(struct inode *ip, doff_t offset, const char *how)
1.1 mycroft 653: {
654: struct mount *mp;
655:
656: mp = ITOV(ip)->v_mount;
1.66 christos 657: printf("%s: bad dir ino %llu at offset %d: %s\n",
658: mp->mnt_stat.f_mntonname, (unsigned long long)ip->i_number,
659: offset, how);
1.56 christos 660: if ((mp->mnt_stat.f_flag & MNT_RDONLY) == 0)
1.1 mycroft 661: panic("bad dir");
662: }
663:
664: /*
665: * Do consistency checking on a directory entry:
666: * record length must be multiple of 4
667: * entry must fit in rest of its DIRBLKSIZ block
668: * record must be large enough to contain entry
1.67 christos 669: * name is not longer than FFS_MAXNAMLEN
1.1 mycroft 670: * name must be as long as advertised, and null terminated
671: */
672: int
1.64 thorpej 673: ufs_dirbadentry(struct vnode *dp, struct direct *ep, int entryoffsetinblock)
1.1 mycroft 674: {
1.30 augustss 675: int i;
1.1 mycroft 676: int namlen;
1.58 mycroft 677: struct ufsmount *ump = VFSTOUFS(dp->v_mount);
678: const int needswap = UFS_MPNEEDSWAP(ump);
679: int dirblksiz = ump->um_dirblksiz;
1.1 mycroft 680:
1.16 kleink 681: #if (BYTE_ORDER == LITTLE_ENDIAN)
1.58 mycroft 682: if (FSFMT(dp) && needswap == 0)
683: namlen = ep->d_type;
684: else
1.16 kleink 685: namlen = ep->d_namlen;
686: #else
1.58 mycroft 687: if (FSFMT(dp) && needswap != 0)
1.16 kleink 688: namlen = ep->d_type;
689: else
1.58 mycroft 690: namlen = ep->d_namlen;
1.16 kleink 691: #endif
1.15 bouyer 692: if ((ufs_rw16(ep->d_reclen, needswap) & 0x3) != 0 ||
693: ufs_rw16(ep->d_reclen, needswap) >
1.40 dbj 694: dirblksiz - (entryoffsetinblock & (dirblksiz - 1)) ||
1.15 bouyer 695: ufs_rw16(ep->d_reclen, needswap) <
1.123 dholland 696: UFS_DIRSIZ(FSFMT(dp), ep, needswap) ||
1.67 christos 697: namlen > FFS_MAXNAMLEN) {
1.1 mycroft 698: /*return (1); */
1.99 simonb 699: printf("First bad, reclen=%#x, DIRSIZ=%lu, namlen=%d, "
700: "flags=%#x, entryoffsetinblock=%d, dirblksiz = %d\n",
1.15 bouyer 701: ufs_rw16(ep->d_reclen, needswap),
1.123 dholland 702: (u_long)UFS_DIRSIZ(FSFMT(dp), ep, needswap),
1.99 simonb 703: namlen, dp->v_mount->mnt_flag, entryoffsetinblock,
704: dirblksiz);
1.1 mycroft 705: goto bad;
706: }
707: if (ep->d_ino == 0)
708: return (0);
709: for (i = 0; i < namlen; i++)
710: if (ep->d_name[i] == '\0') {
711: /*return (1); */
1.9 christos 712: printf("Second bad\n");
1.1 mycroft 713: goto bad;
714: }
715: if (ep->d_name[i])
716: goto bad;
717: return (0);
718: bad:
719: return (1);
720: }
721:
722: /*
1.27 fvdl 723: * Construct a new directory entry after a call to namei, using the
1.110 dholland 724: * name in the componentname argument cnp. The argument ip is the
725: * inode to which the new directory entry will refer.
1.1 mycroft 726: */
1.27 fvdl 727: void
1.64 thorpej 728: ufs_makedirentry(struct inode *ip, struct componentname *cnp,
729: struct direct *newdirp)
1.1 mycroft 730: {
1.27 fvdl 731: newdirp->d_ino = ip->i_number;
732: newdirp->d_namlen = cnp->cn_namelen;
1.51 christos 733: memcpy(newdirp->d_name, cnp->cn_nameptr, (size_t)cnp->cn_namelen);
734: newdirp->d_name[cnp->cn_namelen] = '\0';
1.58 mycroft 735: if (FSFMT(ITOV(ip)))
736: newdirp->d_type = 0;
737: else
1.43 fvdl 738: newdirp->d_type = IFTODT(ip->i_mode);
1.3 mycroft 739: }
740:
741: /*
1.27 fvdl 742: * Write a directory entry after a call to namei, using the parameters
1.110 dholland 743: * that ufs_lookup left in nameidata and in the ufs_lookup_results.
744: *
745: * DVP is the directory to be updated. It must be locked.
746: * ULR is the ufs_lookup_results structure from the final lookup step.
747: * TVP is not used. (XXX: why is it here? remove it)
748: * DIRP is the new directory entry contents.
749: * CNP is the componentname from the final lookup step.
750: * NEWDIRBP is not used and (XXX) should be removed. The previous
751: * comment here said it was used by the now-removed softupdates code.
752: *
753: * The link count of the target inode is *not* incremented; the
754: * caller does that.
755: *
756: * If ulr->ulr_count is 0, ufs_lookup did not find space to insert the
757: * directory entry. ulr_offset, which is the place to put the entry,
758: * should be on a block boundary (and should be at the end of the
759: * directory AFAIK) and a fresh block is allocated to put the new
760: * directory entry in.
761: *
762: * If ulr->ulr_count is not zero, ufs_lookup found a slot to insert
763: * the entry into. This slot ranges from ulr_offset to ulr_offset +
764: * ulr_count. However, this slot may already be partially populated
765: * requiring compaction. See notes below.
766: *
767: * Furthermore, if ulr_count is not zero and ulr_endoff is not the
768: * same as i_size, the directory is truncated to size ulr_endoff.
1.3 mycroft 769: */
1.7 christos 770: int
1.109 dholland 771: ufs_direnter(struct vnode *dvp, const struct ufs_lookup_results *ulr,
772: struct vnode *tvp, struct direct *dirp,
1.64 thorpej 773: struct componentname *cnp, struct buf *newdirbp)
1.27 fvdl 774: {
1.76 elad 775: kauth_cred_t cr;
1.3 mycroft 776: int newentrysize;
777: struct inode *dp;
778: struct buf *bp;
779: u_int dsize;
780: struct direct *ep, *nep;
1.101 ad 781: int error, ret, blkoff, loc, spacefree;
1.3 mycroft 782: char *dirbuf;
1.27 fvdl 783: struct timespec ts;
1.58 mycroft 784: struct ufsmount *ump = VFSTOUFS(dvp->v_mount);
785: const int needswap = UFS_MPNEEDSWAP(ump);
786: int dirblksiz = ump->um_dirblksiz;
1.3 mycroft 787:
1.99 simonb 788: UFS_WAPBL_JLOCK_ASSERT(dvp->v_mount);
789:
1.27 fvdl 790: error = 0;
791: cr = cnp->cn_cred;
792:
1.3 mycroft 793: dp = VTOI(dvp);
1.123 dholland 794: newentrysize = UFS_DIRSIZ(0, dirp, 0);
1.3 mycroft 795:
1.108 dholland 796: if (ulr->ulr_count == 0) {
1.1 mycroft 797: /*
1.108 dholland 798: * If ulr_count is 0, then namei could find no
799: * space in the directory. Here, ulr_offset will
1.1 mycroft 800: * be on a directory block boundary and we will write the
801: * new entry into a fresh block.
802: */
1.108 dholland 803: if (ulr->ulr_offset & (dirblksiz - 1))
1.27 fvdl 804: panic("ufs_direnter: newblk");
1.108 dholland 805: if ((error = UFS_BALLOC(dvp, (off_t)ulr->ulr_offset, dirblksiz,
1.101 ad 806: cr, B_CLRBUF | B_SYNC, &bp)) != 0) {
1.27 fvdl 807: return (error);
808: }
1.108 dholland 809: dp->i_size = ulr->ulr_offset + dirblksiz;
1.44 kristerw 810: DIP_ASSIGN(dp, size, dp->i_size);
1.27 fvdl 811: dp->i_flag |= IN_CHANGE | IN_UPDATE;
1.43 fvdl 812: uvm_vnp_setsize(dvp, dp->i_size);
1.40 dbj 813: dirp->d_reclen = ufs_rw16(dirblksiz, needswap);
1.15 bouyer 814: dirp->d_ino = ufs_rw32(dirp->d_ino, needswap);
1.58 mycroft 815: if (FSFMT(dvp)) {
1.15 bouyer 816: #if (BYTE_ORDER == LITTLE_ENDIAN)
1.16 kleink 817: if (needswap == 0) {
1.15 bouyer 818: #else
1.16 kleink 819: if (needswap != 0) {
1.15 bouyer 820: #endif
821: u_char tmp = dirp->d_namlen;
822: dirp->d_namlen = dirp->d_type;
823: dirp->d_type = tmp;
824: }
1.1 mycroft 825: }
1.108 dholland 826: blkoff = ulr->ulr_offset & (ump->um_mountp->mnt_stat.f_iosize - 1);
1.88 christos 827: memcpy((char *)bp->b_data + blkoff, dirp, newentrysize);
1.61 rumble 828: #ifdef UFS_DIRHASH
829: if (dp->i_dirhash != NULL) {
1.108 dholland 830: ufsdirhash_newblk(dp, ulr->ulr_offset);
831: ufsdirhash_add(dp, dirp, ulr->ulr_offset);
1.61 rumble 832: ufsdirhash_checkblock(dp, (char *)bp->b_data + blkoff,
1.108 dholland 833: ulr->ulr_offset);
1.61 rumble 834: }
835: #endif
1.107 hannken 836: error = VOP_BWRITE(bp->b_vp, bp);
1.78 yamt 837: vfs_timestamp(&ts);
1.69 yamt 838: ret = UFS_UPDATE(dvp, &ts, &ts, UPDATE_DIROP);
1.27 fvdl 839: if (error == 0)
840: return (ret);
1.1 mycroft 841: return (error);
842: }
843:
844: /*
1.110 dholland 845: * If ulr_count is non-zero, then namei found space for the new
1.116 riastrad 846: * entry in the range ulr_offset to ulr_offset + ulr_count
1.27 fvdl 847: * in the directory. To use this space, we may have to compact
848: * the entries located there, by copying them together towards the
849: * beginning of the block, leaving the free space in one usable
850: * chunk at the end.
1.1 mycroft 851: */
852:
853: /*
854: * Increase size of directory if entry eats into new space.
855: * This should never push the size past a new multiple of
1.91 pooka 856: * DIRBLKSIZ.
1.1 mycroft 857: *
858: * N.B. - THIS IS AN ARTIFACT OF 4.2 AND SHOULD NEVER HAPPEN.
859: */
1.108 dholland 860: if (ulr->ulr_offset + ulr->ulr_count > dp->i_size) {
861: #ifdef DIAGNOSTIC
862: printf("ufs_direnter: reached 4.2-only block, "
863: "not supposed to happen\n");
864: #endif
865: dp->i_size = ulr->ulr_offset + ulr->ulr_count;
1.44 kristerw 866: DIP_ASSIGN(dp, size, dp->i_size);
1.54 dbj 867: dp->i_flag |= IN_CHANGE | IN_UPDATE;
1.99 simonb 868: UFS_WAPBL_UPDATE(dvp, NULL, NULL, UPDATE_DIROP);
1.43 fvdl 869: }
1.1 mycroft 870: /*
871: * Get the block containing the space for the new directory entry.
872: */
1.108 dholland 873: error = ufs_blkatoff(dvp, (off_t)ulr->ulr_offset, &dirbuf, &bp, true);
1.27 fvdl 874: if (error) {
1.1 mycroft 875: return (error);
1.27 fvdl 876: }
1.1 mycroft 877: /*
878: * Find space for the new entry. In the simple case, the entry at
879: * offset base will have the space. If it does not, then namei
1.116 riastrad 880: * arranged that compacting the region ulr_offset to
881: * ulr_offset + ulr_count would yield the space.
1.1 mycroft 882: */
883: ep = (struct direct *)dirbuf;
1.123 dholland 884: dsize = (ep->d_ino != 0) ? UFS_DIRSIZ(FSFMT(dvp), ep, needswap) : 0;
1.15 bouyer 885: spacefree = ufs_rw16(ep->d_reclen, needswap) - dsize;
1.108 dholland 886: for (loc = ufs_rw16(ep->d_reclen, needswap); loc < ulr->ulr_count; ) {
1.72 yamt 887: uint16_t reclen;
888:
1.1 mycroft 889: nep = (struct direct *)(dirbuf + loc);
1.72 yamt 890:
891: /* Trim the existing slot (NB: dsize may be zero). */
892: ep->d_reclen = ufs_rw16(dsize, needswap);
893: ep = (struct direct *)((char *)ep + dsize);
894:
895: reclen = ufs_rw16(nep->d_reclen, needswap);
896: loc += reclen;
897: if (nep->d_ino == 0) {
898: /*
899: * A mid-block unused entry. Such entries are
900: * never created by the kernel, but fsck_ffs
901: * can create them (and it doesn't fix them).
902: *
903: * Add up the free space, and initialise the
904: * relocated entry since we don't memcpy it.
905: */
906: spacefree += reclen;
907: ep->d_ino = 0;
908: dsize = 0;
909: continue;
1.1 mycroft 910: }
1.123 dholland 911: dsize = UFS_DIRSIZ(FSFMT(dvp), nep, needswap);
1.72 yamt 912: spacefree += reclen - dsize;
1.61 rumble 913: #ifdef UFS_DIRHASH
914: if (dp->i_dirhash != NULL)
915: ufsdirhash_move(dp, nep,
1.108 dholland 916: ulr->ulr_offset + ((char *)nep - dirbuf),
917: ulr->ulr_offset + ((char *)ep - dirbuf));
1.61 rumble 918: #endif
1.101 ad 919: memcpy((void *)ep, (void *)nep, dsize);
1.1 mycroft 920: }
921: /*
1.72 yamt 922: * Here, `ep' points to a directory entry containing `dsize' in-use
923: * bytes followed by `spacefree' unused bytes. If ep->d_ino == 0,
924: * then the entry is completely unused (dsize == 0). The value
925: * of ep->d_reclen is always indeterminate.
926: *
1.1 mycroft 927: * Update the pointer fields in the previous entry (if any),
928: * copy in the new entry, and write out the block.
929: */
1.3 mycroft 930: if (ep->d_ino == 0 ||
1.122 dholland 931: (ufs_rw32(ep->d_ino, needswap) == UFS_WINO &&
1.18 perry 932: memcmp(ep->d_name, dirp->d_name, dirp->d_namlen) == 0)) {
1.1 mycroft 933: if (spacefree + dsize < newentrysize)
1.27 fvdl 934: panic("ufs_direnter: compact1");
1.3 mycroft 935: dirp->d_reclen = spacefree + dsize;
1.1 mycroft 936: } else {
937: if (spacefree < newentrysize)
1.27 fvdl 938: panic("ufs_direnter: compact2");
1.3 mycroft 939: dirp->d_reclen = spacefree;
1.15 bouyer 940: ep->d_reclen = ufs_rw16(dsize, needswap);
1.1 mycroft 941: ep = (struct direct *)((char *)ep + dsize);
942: }
1.15 bouyer 943: dirp->d_reclen = ufs_rw16(dirp->d_reclen, needswap);
944: dirp->d_ino = ufs_rw32(dirp->d_ino, needswap);
1.58 mycroft 945: if (FSFMT(dvp)) {
1.15 bouyer 946: #if (BYTE_ORDER == LITTLE_ENDIAN)
1.16 kleink 947: if (needswap == 0) {
1.15 bouyer 948: #else
1.16 kleink 949: if (needswap != 0) {
1.15 bouyer 950: #endif
951: u_char tmp = dirp->d_namlen;
952: dirp->d_namlen = dirp->d_type;
953: dirp->d_type = tmp;
954: }
1.27 fvdl 955: }
1.61 rumble 956: #ifdef UFS_DIRHASH
957: if (dp->i_dirhash != NULL && (ep->d_ino == 0 ||
958: dirp->d_reclen == spacefree))
1.108 dholland 959: ufsdirhash_add(dp, dirp, ulr->ulr_offset + ((char *)ep - dirbuf));
1.61 rumble 960: #endif
1.88 christos 961: memcpy((void *)ep, (void *)dirp, (u_int)newentrysize);
1.61 rumble 962: #ifdef UFS_DIRHASH
963: if (dp->i_dirhash != NULL)
964: ufsdirhash_checkblock(dp, dirbuf -
1.108 dholland 965: (ulr->ulr_offset & (dirblksiz - 1)),
966: ulr->ulr_offset & ~(dirblksiz - 1));
1.61 rumble 967: #endif
1.107 hannken 968: error = VOP_BWRITE(bp->b_vp, bp);
1.1 mycroft 969: dp->i_flag |= IN_CHANGE | IN_UPDATE;
1.27 fvdl 970: /*
971: * If all went well, and the directory can be shortened, proceed
972: * with the truncation. Note that we have to unlock the inode for
973: * the entry that we just entered, as the truncation may need to
974: * lock other inodes which can lead to deadlock if we also hold a
975: * lock on the newly entered node.
976: */
1.108 dholland 977: if (error == 0 && ulr->ulr_endoff && ulr->ulr_endoff < dp->i_size) {
1.61 rumble 978: #ifdef UFS_DIRHASH
979: if (dp->i_dirhash != NULL)
1.108 dholland 980: ufsdirhash_dirtrunc(dp, ulr->ulr_endoff);
1.61 rumble 981: #endif
1.108 dholland 982: (void) UFS_TRUNCATE(dvp, (off_t)ulr->ulr_endoff, IO_SYNC, cr);
1.27 fvdl 983: }
1.99 simonb 984: UFS_WAPBL_UPDATE(dvp, NULL, NULL, UPDATE_DIROP);
1.1 mycroft 985: return (error);
986: }
987:
988: /*
1.110 dholland 989: * Remove a directory entry after a call to namei, using the
990: * parameters that ufs_lookup left in nameidata and in the
991: * ufs_lookup_results.
992: *
993: * DVP is the directory to be updated. It must be locked.
994: * ULR is the ufs_lookup_results structure from the final lookup step.
995: * IP, if not null, is the inode being unlinked.
996: * FLAGS may contain DOWHITEOUT.
997: * ISRMDIR is not used and (XXX) should be removed.
998: *
999: * If FLAGS contains DOWHITEOUT the entry is replaced with a whiteout
1000: * instead of being cleared.
1001: *
1002: * ulr->ulr_offset contains the position of the directory entry
1003: * to be removed.
1004: *
1005: * ulr->ulr_reclen contains the size of the directory entry to be
1006: * removed.
1007: *
1008: * ulr->ulr_count contains the size of the *previous* directory
1009: * entry. This allows finding it, for free space management. If
1010: * ulr_count is 0, the target entry is at the beginning of the
1011: * directory. (Does this ever happen? The first entry should be ".",
1012: * which should only be removed at rmdir time. Does rmdir come here
1013: * to clear out the "." and ".." entries? Perhaps, but I doubt it.)
1014: *
1015: * The space is marked free by adding it to the record length (not
1016: * name length) of the preceding entry. If the first entry becomes
1017: * free, it is marked free by setting the inode number to 0.
1018: *
1019: * The link count of IP is decremented. Note that this is not the
1020: * inverse behavior of ufs_direnter, which does not adjust link
1021: * counts. Sigh.
1.1 mycroft 1022: */
1023: int
1.109 dholland 1024: ufs_dirremove(struct vnode *dvp, const struct ufs_lookup_results *ulr,
1025: struct inode *ip, int flags, int isrmdir)
1.1 mycroft 1026: {
1.59 mycroft 1027: struct inode *dp = VTOI(dvp);
1.1 mycroft 1028: struct direct *ep;
1029: struct buf *bp;
1030: int error;
1.59 mycroft 1031: const int needswap = UFS_MPNEEDSWAP(dp->i_ump);
1.1 mycroft 1032:
1.99 simonb 1033: UFS_WAPBL_JLOCK_ASSERT(dvp->v_mount);
1034:
1.27 fvdl 1035: if (flags & DOWHITEOUT) {
1.3 mycroft 1036: /*
1.122 dholland 1037: * Whiteout entry: set d_ino to UFS_WINO.
1.3 mycroft 1038: */
1.108 dholland 1039: error = ufs_blkatoff(dvp, (off_t)ulr->ulr_offset, (void *)&ep,
1.97 hannken 1040: &bp, true);
1.7 christos 1041: if (error)
1.3 mycroft 1042: return (error);
1.122 dholland 1043: ep->d_ino = ufs_rw32(UFS_WINO, needswap);
1.3 mycroft 1044: ep->d_type = DT_WHT;
1.27 fvdl 1045: goto out;
1046: }
1047:
1.73 yamt 1048: if ((error = ufs_blkatoff(dvp,
1.108 dholland 1049: (off_t)(ulr->ulr_offset - ulr->ulr_count), (void *)&ep, &bp, true)) != 0)
1.3 mycroft 1050: return (error);
1051:
1.61 rumble 1052: #ifdef UFS_DIRHASH
1053: /*
1054: * Remove the dirhash entry. This is complicated by the fact
1.116 riastrad 1055: * that `ep' is the previous entry when ulr_count != 0.
1.61 rumble 1056: */
1057: if (dp->i_dirhash != NULL)
1.108 dholland 1058: ufsdirhash_remove(dp, (ulr->ulr_count == 0) ? ep :
1.85 bouyer 1059: (struct direct *)((char *)ep +
1.108 dholland 1060: ufs_rw16(ep->d_reclen, needswap)), ulr->ulr_offset);
1.61 rumble 1061: #endif
1062:
1.108 dholland 1063: if (ulr->ulr_count == 0) {
1.1 mycroft 1064: /*
1065: * First entry in block: set d_ino to zero.
1066: */
1067: ep->d_ino = 0;
1.27 fvdl 1068: } else {
1069: /*
1070: * Collapse new free space into previous entry.
1071: */
1072: ep->d_reclen =
1.108 dholland 1073: ufs_rw16(ufs_rw16(ep->d_reclen, needswap) + ulr->ulr_reclen,
1.36 lukem 1074: needswap);
1.27 fvdl 1075: }
1.61 rumble 1076:
1077: #ifdef UFS_DIRHASH
1078: if (dp->i_dirhash != NULL) {
1079: int dirblksiz = ip->i_ump->um_dirblksiz;
1080: ufsdirhash_checkblock(dp, (char *)ep -
1.108 dholland 1081: ((ulr->ulr_offset - ulr->ulr_count) & (dirblksiz - 1)),
1082: ulr->ulr_offset & ~(dirblksiz - 1));
1.61 rumble 1083: }
1084: #endif
1085:
1.27 fvdl 1086: out:
1.101 ad 1087: if (ip) {
1088: ip->i_nlink--;
1089: DIP_ASSIGN(ip, nlink, ip->i_nlink);
1090: ip->i_flag |= IN_CHANGE;
1091: UFS_WAPBL_UPDATE(ITOV(ip), NULL, NULL, 0);
1.1 mycroft 1092: }
1.118 dholland 1093: /*
1094: * XXX did it ever occur to anyone that it might be a good
1095: * idea to restore ip->i_nlink if this fails? Or something?
1096: * Currently on error return from this function the state of
1097: * ip->i_nlink depends on what happened, and callers
1098: * definitely do not take this into account.
1099: */
1.107 hannken 1100: error = VOP_BWRITE(bp->b_vp, bp);
1.1 mycroft 1101: dp->i_flag |= IN_CHANGE | IN_UPDATE;
1.57 hannken 1102: /*
1103: * If the last named reference to a snapshot goes away,
1104: * drop its snapshot reference so that it will be reclaimed
1105: * when last open reference goes away.
1106: */
1107: if (ip != 0 && (ip->i_flags & SF_SNAPSHOT) != 0 &&
1.101 ad 1108: ip->i_nlink == 0)
1.124 hannken 1109: UFS_SNAPGONE(ITOV(ip));
1.99 simonb 1110: UFS_WAPBL_UPDATE(dvp, NULL, NULL, 0);
1.1 mycroft 1111: return (error);
1112: }
1113:
1114: /*
1.110 dholland 1115: * Rewrite an existing directory entry to point at the inode supplied.
1116: *
1117: * DP is the directory to update.
1118: * OFFSET is the position of the entry in question. It may come
1119: * from ulr_offset of a ufs_lookup_results.
1120: * OIP is the old inode the directory previously pointed to.
1121: * NEWINUM is the number of the new inode.
1122: * NEWTYPE is the new value for the type field of the directory entry.
1123: * (This is ignored if the fs doesn't support that.)
1124: * ISRMDIR is not used and (XXX) should be removed.
1125: * IFLAGS are added to DP's inode flags.
1126: *
1127: * The link count of OIP is decremented. Note that the link count of
1128: * the new inode is *not* incremented. Yay for symmetry.
1.1 mycroft 1129: */
1130: int
1.109 dholland 1131: ufs_dirrewrite(struct inode *dp, off_t offset,
1132: struct inode *oip, ino_t newinum, int newtype,
1.64 thorpej 1133: int isrmdir, int iflags)
1.1 mycroft 1134: {
1135: struct buf *bp;
1136: struct direct *ep;
1137: struct vnode *vdp = ITOV(dp);
1138: int error;
1139:
1.109 dholland 1140: error = ufs_blkatoff(vdp, offset, (void *)&ep, &bp, true);
1.7 christos 1141: if (error)
1.1 mycroft 1142: return (error);
1.59 mycroft 1143: ep->d_ino = ufs_rw32(newinum, UFS_MPNEEDSWAP(dp->i_ump));
1.58 mycroft 1144: if (!FSFMT(vdp))
1.27 fvdl 1145: ep->d_type = newtype;
1.101 ad 1146: oip->i_nlink--;
1147: DIP_ASSIGN(oip, nlink, oip->i_nlink);
1148: oip->i_flag |= IN_CHANGE;
1149: UFS_WAPBL_UPDATE(ITOV(oip), NULL, NULL, UPDATE_DIROP);
1.107 hannken 1150: error = VOP_BWRITE(bp->b_vp, bp);
1.49 pk 1151: dp->i_flag |= iflags;
1.57 hannken 1152: /*
1153: * If the last named reference to a snapshot goes away,
1154: * drop its snapshot reference so that it will be reclaimed
1155: * when last open reference goes away.
1156: */
1.101 ad 1157: if ((oip->i_flags & SF_SNAPSHOT) != 0 && oip->i_nlink == 0)
1.124 hannken 1158: UFS_SNAPGONE(ITOV(oip));
1.99 simonb 1159: UFS_WAPBL_UPDATE(vdp, NULL, NULL, UPDATE_DIROP);
1.1 mycroft 1160: return (error);
1161: }
1162:
1163: /*
1164: * Check if a directory is empty or not.
1165: * Inode supplied must be locked.
1166: *
1167: * Using a struct dirtemplate here is not precisely
1168: * what we want, but better than using a struct direct.
1169: *
1170: * NB: does not handle corrupted directories.
1171: */
1172: int
1.76 elad 1173: ufs_dirempty(struct inode *ip, ino_t parentino, kauth_cred_t cred)
1.1 mycroft 1174: {
1.43 fvdl 1175: doff_t off;
1.1 mycroft 1176: struct dirtemplate dbuf;
1.30 augustss 1177: struct direct *dp = (struct direct *)&dbuf;
1.17 thorpej 1178: int error, namlen;
1179: size_t count;
1.36 lukem 1180: const int needswap = UFS_IPNEEDSWAP(ip);
1.1 mycroft 1181: #define MINDIRSIZ (sizeof (struct dirtemplate) / 2)
1182:
1.43 fvdl 1183: for (off = 0; off < ip->i_size;
1.36 lukem 1184: off += ufs_rw16(dp->d_reclen, needswap)) {
1.132.4.1! skrll 1185: error = ufs_bufio(UIO_READ, ITOV(ip), (void *)dp, MINDIRSIZ,
! 1186: off, IO_NODELOCKED, cred, &count, NULL);
1.1 mycroft 1187: /*
1188: * Since we read MINDIRSIZ, residual must
1189: * be 0 unless we're at end of file.
1190: */
1191: if (error || count != 0)
1192: return (0);
1193: /* avoid infinite loops */
1194: if (dp->d_reclen == 0)
1195: return (0);
1196: /* skip empty entries */
1.122 dholland 1197: if (dp->d_ino == 0 || ufs_rw32(dp->d_ino, needswap) == UFS_WINO)
1.1 mycroft 1198: continue;
1199: /* accept only "." and ".." */
1.16 kleink 1200: #if (BYTE_ORDER == LITTLE_ENDIAN)
1.58 mycroft 1201: if (FSFMT(ITOV(ip)) && needswap == 0)
1202: namlen = dp->d_type;
1203: else
1.16 kleink 1204: namlen = dp->d_namlen;
1205: #else
1.58 mycroft 1206: if (FSFMT(ITOV(ip)) && needswap != 0)
1.16 kleink 1207: namlen = dp->d_type;
1208: else
1209: namlen = dp->d_namlen;
1210: #endif
1.1 mycroft 1211: if (namlen > 2)
1212: return (0);
1213: if (dp->d_name[0] != '.')
1214: return (0);
1215: /*
1216: * At this point namlen must be 1 or 2.
1217: * 1 implies ".", 2 implies ".." if second
1218: * char is also "."
1219: */
1.27 fvdl 1220: if (namlen == 1 &&
1.36 lukem 1221: ufs_rw32(dp->d_ino, needswap) == ip->i_number)
1.1 mycroft 1222: continue;
1.15 bouyer 1223: if (dp->d_name[1] == '.' &&
1.36 lukem 1224: ufs_rw32(dp->d_ino, needswap) == parentino)
1.1 mycroft 1225: continue;
1226: return (0);
1227: }
1228: return (1);
1229: }
1230:
1.73 yamt 1231: #define UFS_DIRRABLKS 0
1232: int ufs_dirrablks = UFS_DIRRABLKS;
1233:
1234: /*
1235: * ufs_blkatoff: Return buffer with the contents of block "offset" from
1.114 yamt 1236: * the beginning of directory "vp". If "res" is non-NULL, fill it in with
1.98 hannken 1237: * a pointer to the remaining space in the directory. If the caller intends
1238: * to modify the buffer returned, "modify" must be true.
1.73 yamt 1239: */
1240:
1241: int
1.97 hannken 1242: ufs_blkatoff(struct vnode *vp, off_t offset, char **res, struct buf **bpp,
1243: bool modify)
1.73 yamt 1244: {
1.127 martin 1245: struct inode *ip __diagused;
1.73 yamt 1246: struct buf *bp;
1247: daddr_t lbn;
1248: const int dirrablks = ufs_dirrablks;
1.92 pooka 1249: daddr_t *blks;
1250: int *blksizes;
1251: int run, error;
1.73 yamt 1252: struct mount *mp = vp->v_mount;
1253: const int bshift = mp->mnt_fs_bshift;
1254: const int bsize = 1 << bshift;
1255: off_t eof;
1256:
1.99 simonb 1257: blks = kmem_alloc((1 + dirrablks) * sizeof(daddr_t), KM_SLEEP);
1258: blksizes = kmem_alloc((1 + dirrablks) * sizeof(int), KM_SLEEP);
1.73 yamt 1259: ip = VTOI(vp);
1260: KASSERT(vp->v_size == ip->i_size);
1.74 yamt 1261: GOP_SIZE(vp, vp->v_size, &eof, 0);
1.73 yamt 1262: lbn = offset >> bshift;
1.92 pooka 1263:
1.73 yamt 1264: for (run = 0; run <= dirrablks;) {
1265: const off_t curoff = lbn << bshift;
1266: const int size = MIN(eof - curoff, bsize);
1267:
1268: if (size == 0) {
1269: break;
1270: }
1271: KASSERT(curoff < eof);
1272: blks[run] = lbn;
1273: blksizes[run] = size;
1274: lbn++;
1275: run++;
1276: if (size != bsize) {
1277: break;
1278: }
1279: }
1280: KASSERT(run >= 1);
1281: error = breadn(vp, blks[0], blksizes[0], &blks[1], &blksizes[1],
1.132.4.1! skrll 1282: run - 1, (modify ? B_MODIFY : 0), &bp);
1.73 yamt 1283: if (error != 0) {
1284: *bpp = NULL;
1.92 pooka 1285: goto out;
1.73 yamt 1286: }
1287: if (res) {
1288: *res = (char *)bp->b_data + (offset & (bsize - 1));
1289: }
1290: *bpp = bp;
1.92 pooka 1291:
1292: out:
1.99 simonb 1293: kmem_free(blks, (1 + dirrablks) * sizeof(daddr_t));
1294: kmem_free(blksizes, (1 + dirrablks) * sizeof(int));
1.92 pooka 1295: return error;
1.73 yamt 1296: }
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