2 * modified for Lites 1.1
4 * Aug 1995, Godmar Back (gback@cs.utah.edu)
5 * University of Utah, Department of Computer Science
8 * SPDX-License-Identifier: BSD-3-Clause
10 * Copyright (c) 1989, 1993
11 * The Regents of the University of California. All rights reserved.
12 * (c) UNIX System Laboratories, Inc.
13 * All or some portions of this file are derived from material licensed
14 * to the University of California by American Telephone and Telegraph
15 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
16 * the permission of UNIX System Laboratories, Inc.
18 * Redistribution and use in source and binary forms, with or without
19 * modification, are permitted provided that the following conditions
21 * 1. Redistributions of source code must retain the above copyright
22 * notice, this list of conditions and the following disclaimer.
23 * 2. Redistributions in binary form must reproduce the above copyright
24 * notice, this list of conditions and the following disclaimer in the
25 * documentation and/or other materials provided with the distribution.
26 * 3. Neither the name of the University nor the names of its contributors
27 * may be used to endorse or promote products derived from this software
28 * without specific prior written permission.
30 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
31 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
32 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
34 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
35 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
36 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
37 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
38 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
39 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
42 * @(#)ufs_lookup.c 8.6 (Berkeley) 4/1/94
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/namei.h>
51 #include <sys/endian.h>
52 #include <sys/mount.h>
53 #include <sys/vnode.h>
54 #include <sys/malloc.h>
55 #include <sys/dirent.h>
56 #include <sys/sysctl.h>
58 #include <ufs/ufs/dir.h>
60 #include <fs/ext2fs/inode.h>
61 #include <fs/ext2fs/ext2_mount.h>
62 #include <fs/ext2fs/ext2fs.h>
63 #include <fs/ext2fs/ext2_dinode.h>
64 #include <fs/ext2fs/ext2_dir.h>
65 #include <fs/ext2fs/ext2_extern.h>
66 #include <fs/ext2fs/fs.h>
69 static int dirchk = 1;
71 static int dirchk = 0;
74 static SYSCTL_NODE(_vfs, OID_AUTO, e2fs, CTLFLAG_RD, 0, "EXT2FS filesystem");
75 SYSCTL_INT(_vfs_e2fs, OID_AUTO, dircheck, CTLFLAG_RW, &dirchk, 0, "");
78 DIRBLKSIZE in ffs is DEV_BSIZE (in most cases 512)
79 while it is the native blocksize in ext2fs - thus, a #define
80 is no longer appropriate
84 static u_char ext2_ft_to_dt[] = {
85 DT_UNKNOWN, /* EXT2_FT_UNKNOWN */
86 DT_REG, /* EXT2_FT_REG_FILE */
87 DT_DIR, /* EXT2_FT_DIR */
88 DT_CHR, /* EXT2_FT_CHRDEV */
89 DT_BLK, /* EXT2_FT_BLKDEV */
90 DT_FIFO, /* EXT2_FT_FIFO */
91 DT_SOCK, /* EXT2_FT_SOCK */
92 DT_LNK, /* EXT2_FT_SYMLINK */
95 ((ft) < nitems(ext2_ft_to_dt) ? ext2_ft_to_dt[(ft)] : DT_UNKNOWN)
97 static u_char dt_to_ext2_ft[] = {
98 EXT2_FT_UNKNOWN, /* DT_UNKNOWN */
99 EXT2_FT_FIFO, /* DT_FIFO */
100 EXT2_FT_CHRDEV, /* DT_CHR */
101 EXT2_FT_UNKNOWN, /* unused */
102 EXT2_FT_DIR, /* DT_DIR */
103 EXT2_FT_UNKNOWN, /* unused */
104 EXT2_FT_BLKDEV, /* DT_BLK */
105 EXT2_FT_UNKNOWN, /* unused */
106 EXT2_FT_REG_FILE, /* DT_REG */
107 EXT2_FT_UNKNOWN, /* unused */
108 EXT2_FT_SYMLINK, /* DT_LNK */
109 EXT2_FT_UNKNOWN, /* unused */
110 EXT2_FT_SOCK, /* DT_SOCK */
111 EXT2_FT_UNKNOWN, /* unused */
112 EXT2_FT_UNKNOWN, /* DT_WHT */
115 ((dt) < nitems(dt_to_ext2_ft) ? dt_to_ext2_ft[(dt)] : EXT2_FT_UNKNOWN)
117 static int ext2_dirbadentry(struct vnode *dp, struct ext2fs_direct_2 *de,
118 int entryoffsetinblock);
119 static int ext2_is_dot_entry(struct componentname *cnp);
120 static int ext2_lookup_ino(struct vnode *vdp, struct vnode **vpp,
121 struct componentname *cnp, ino_t *dd_ino);
124 ext2_is_dot_entry(struct componentname *cnp)
126 if (cnp->cn_namelen <= 2 && cnp->cn_nameptr[0] == '.' &&
127 (cnp->cn_nameptr[1] == '.' || cnp->cn_nameptr[1] == '\0'))
133 * Vnode op for reading directories.
136 ext2_readdir(struct vop_readdir_args *ap)
138 struct vnode *vp = ap->a_vp;
139 struct uio *uio = ap->a_uio;
142 struct ext2fs_direct_2 *dp, *edp;
145 off_t offset, startoffset;
146 size_t readcnt, skipcnt;
149 int DIRBLKSIZ = VTOI(ap->a_vp)->i_e2fs->e2fs_bsize;
152 if (uio->uio_offset < 0)
155 if (ap->a_ncookies != NULL) {
156 if (uio->uio_resid < 0)
159 ncookies = uio->uio_resid;
160 if (uio->uio_offset >= ip->i_size)
162 else if (ip->i_size - uio->uio_offset < ncookies)
163 ncookies = ip->i_size - uio->uio_offset;
164 ncookies = ncookies / (offsetof(struct ext2fs_direct_2,
165 e2d_namlen) + 4) + 1;
166 cookies = malloc(ncookies * sizeof(*cookies), M_TEMP, M_WAITOK);
167 *ap->a_ncookies = ncookies;
168 *ap->a_cookies = cookies;
173 offset = startoffset = uio->uio_offset;
174 startresid = uio->uio_resid;
176 while (error == 0 && uio->uio_resid > 0 &&
177 uio->uio_offset < ip->i_size) {
178 error = ext2_blkatoff(vp, uio->uio_offset, NULL, &bp);
181 if (bp->b_offset + bp->b_bcount > ip->i_size)
182 readcnt = ip->i_size - bp->b_offset;
184 readcnt = bp->b_bcount;
185 skipcnt = (size_t)(uio->uio_offset - bp->b_offset) &
186 ~(size_t)(DIRBLKSIZ - 1);
187 offset = bp->b_offset + skipcnt;
188 dp = (struct ext2fs_direct_2 *)&bp->b_data[skipcnt];
189 edp = (struct ext2fs_direct_2 *)&bp->b_data[readcnt];
190 while (error == 0 && uio->uio_resid > 0 && dp < edp) {
191 if (dp->e2d_reclen <= offsetof(struct ext2fs_direct_2,
192 e2d_namlen) || (caddr_t)dp + dp->e2d_reclen >
198 * "New" ext2fs directory entries differ in 3 ways
199 * from ufs on-disk ones:
200 * - the name is not necessarily NUL-terminated.
201 * - the file type field always exists and always
202 * follows the name length field.
203 * - the file type is encoded in a different way.
205 * "Old" ext2fs directory entries need no special
206 * conversions, since they are binary compatible
207 * with "new" entries having a file type of 0 (i.e.,
208 * EXT2_FT_UNKNOWN). Splitting the old name length
209 * field didn't make a mess like it did in ufs,
210 * because ext2fs uses a machine-independent disk
213 dstdp.d_namlen = dp->e2d_namlen;
214 dstdp.d_type = FTTODT(dp->e2d_type);
215 if (offsetof(struct ext2fs_direct_2, e2d_namlen) +
216 dstdp.d_namlen > dp->e2d_reclen) {
220 if (offset < startoffset || dp->e2d_ino == 0)
222 dstdp.d_fileno = dp->e2d_ino;
223 dstdp.d_reclen = GENERIC_DIRSIZ(&dstdp);
224 bcopy(dp->e2d_name, dstdp.d_name, dstdp.d_namlen);
225 dstdp.d_name[dstdp.d_namlen] = '\0';
226 if (dstdp.d_reclen > uio->uio_resid) {
227 if (uio->uio_resid == startresid)
234 error = uiomove((caddr_t)&dstdp, dstdp.d_reclen, uio);
237 if (cookies != NULL) {
238 KASSERT(ncookies > 0,
239 ("ext2_readdir: cookies buffer too small"));
240 *cookies = offset + dp->e2d_reclen;
245 offset += dp->e2d_reclen;
246 dp = (struct ext2fs_direct_2 *)((caddr_t)dp +
250 uio->uio_offset = offset;
252 /* We need to correct uio_offset. */
253 uio->uio_offset = offset;
254 if (error == EJUSTRETURN)
256 if (ap->a_ncookies != NULL) {
258 ap->a_ncookies -= ncookies;
260 free(*ap->a_cookies, M_TEMP);
262 *ap->a_cookies = NULL;
265 if (error == 0 && ap->a_eofflag)
266 *ap->a_eofflag = ip->i_size <= uio->uio_offset;
271 * Convert a component of a pathname into a pointer to a locked inode.
272 * This is a very central and rather complicated routine.
273 * If the file system is not maintained in a strict tree hierarchy,
274 * this can result in a deadlock situation (see comments in code below).
276 * The cnp->cn_nameiop argument is LOOKUP, CREATE, RENAME, or DELETE depending
277 * on whether the name is to be looked up, created, renamed, or deleted.
278 * When CREATE, RENAME, or DELETE is specified, information usable in
279 * creating, renaming, or deleting a directory entry may be calculated.
280 * If flag has LOCKPARENT or'ed into it and the target of the pathname
281 * exists, lookup returns both the target and its parent directory locked.
282 * When creating or renaming and LOCKPARENT is specified, the target may
283 * not be ".". When deleting and LOCKPARENT is specified, the target may
284 * be "."., but the caller must check to ensure it does an vrele and vput
285 * instead of two vputs.
287 * Overall outline of ext2_lookup:
289 * search for name in directory, to found or notfound
291 * if creating, return locked directory, leaving info on available slots
294 * if at end of path and deleting, return information to allow delete
295 * if at end of path and rewriting (RENAME and LOCKPARENT), lock target
296 * inode and return info to allow rewrite
297 * if not at end, add name to cache; if at end and neither creating
298 * nor deleting, add name to cache
301 ext2_lookup(struct vop_cachedlookup_args *ap)
304 return (ext2_lookup_ino(ap->a_dvp, ap->a_vpp, ap->a_cnp, NULL));
308 ext2_lookup_ino(struct vnode *vdp, struct vnode **vpp, struct componentname *cnp,
311 struct inode *dp; /* inode for directory being searched */
312 struct buf *bp; /* a buffer of directory entries */
313 struct ext2fs_direct_2 *ep; /* the current directory entry */
314 int entryoffsetinblock; /* offset of ep in bp's buffer */
315 struct ext2fs_searchslot ss;
316 doff_t i_diroff; /* cached i_diroff value */
317 doff_t i_offset; /* cached i_offset value */
318 int numdirpasses; /* strategy for directory search */
319 doff_t endsearch; /* offset to end directory search */
320 doff_t prevoff; /* prev entry dp->i_offset */
321 struct vnode *pdp; /* saved dp during symlink work */
322 struct vnode *tdp; /* returned by VFS_VGET */
323 doff_t enduseful; /* pointer past last used dir slot */
324 u_long bmask; /* block offset mask */
326 struct ucred *cred = cnp->cn_cred;
327 int flags = cnp->cn_flags;
328 int nameiop = cnp->cn_nameiop;
333 int DIRBLKSIZ = VTOI(vdp)->i_e2fs->e2fs_bsize;
339 bmask = VFSTOEXT2(vdp->v_mount)->um_mountp->mnt_stat.f_iosize - 1;
345 * We now have a segment name to search for, and a directory to search.
347 * Suppress search for slots unless creating
348 * file and at end of pathname, in which case
349 * we watch for a place to put the new file in
350 * case it doesn't already exist.
352 i_diroff = dp->i_diroff;
353 ss.slotstatus = FOUND;
354 ss.slotfreespace = ss.slotsize = ss.slotneeded = 0;
355 if ((nameiop == CREATE || nameiop == RENAME) &&
356 (flags & ISLASTCN)) {
357 ss.slotstatus = NONE;
358 ss.slotneeded = EXT2_DIR_REC_LEN(cnp->cn_namelen);
360 * was ss.slotneeded = (sizeof(struct direct) - MAXNAMLEN +
361 * cnp->cn_namelen + 3) &~ 3;
365 * Try to lookup dir entry using htree directory index.
367 * If we got an error or we want to find '.' or '..' entry,
368 * we will fall back to linear search.
370 if (!ext2_is_dot_entry(cnp) && ext2_htree_has_idx(dp)) {
372 entryoffsetinblock = 0;
373 switch (ext2_htree_lookup(dp, cnp->cn_nameptr, cnp->cn_namelen,
374 &bp, &entryoffsetinblock, &i_offset, &prevoff,
377 ep = (struct ext2fs_direct_2 *)((char *)bp->b_data +
381 i_offset = roundup2(dp->i_size, DIRBLKSIZ);
385 * Something failed; just fallback to do a linear
393 * If there is cached information on a previous search of
394 * this directory, pick up where we last left off.
395 * We cache only lookups as these are the most common
396 * and have the greatest payoff. Caching CREATE has little
397 * benefit as it usually must search the entire directory
398 * to determine that the entry does not exist. Caching the
399 * location of the last DELETE or RENAME has not reduced
400 * profiling time and hence has been removed in the interest
403 if (nameiop != LOOKUP || i_diroff == 0 ||
404 i_diroff > dp->i_size) {
405 entryoffsetinblock = 0;
410 if ((entryoffsetinblock = i_offset & bmask) &&
411 (error = ext2_blkatoff(vdp, (off_t)i_offset, NULL,
415 nchstats.ncs_2passes++;
418 endsearch = roundup2(dp->i_size, DIRBLKSIZ);
422 while (i_offset < endsearch) {
424 * If necessary, get the next directory block.
428 error = ext2_blkatoff(vdp, (off_t)i_offset, NULL, &bp);
431 entryoffsetinblock = 0;
433 * If still looking for a slot, and at a DIRBLKSIZE
434 * boundary, have to start looking for free space again.
436 if (ss.slotstatus == NONE &&
437 (entryoffsetinblock & (DIRBLKSIZ - 1)) == 0) {
439 ss.slotfreespace = 0;
441 error = ext2_search_dirblock(dp, bp->b_data, &entry_found,
442 cnp->cn_nameptr, cnp->cn_namelen,
443 &entryoffsetinblock, &i_offset, &prevoff,
450 ep = (struct ext2fs_direct_2 *)((char *)bp->b_data +
451 (entryoffsetinblock & bmask));
459 * If we started in the middle of the directory and failed
460 * to find our target, we must check the beginning as well.
462 if (numdirpasses == 2) {
465 endsearch = i_diroff;
471 * If creating, and at end of pathname and current
472 * directory has not been removed, then can consider
473 * allowing file to be created.
475 if ((nameiop == CREATE || nameiop == RENAME) &&
476 (flags & ISLASTCN) && dp->i_nlink != 0) {
478 * Access for write is interpreted as allowing
479 * creation of files in the directory.
481 if ((error = VOP_ACCESS(vdp, VWRITE, cred, cnp->cn_thread)) != 0)
484 * Return an indication of where the new directory
485 * entry should be put. If we didn't find a slot,
486 * then set dp->i_count to 0 indicating
487 * that the new slot belongs at the end of the
488 * directory. If we found a slot, then the new entry
489 * can be put in the range from dp->i_offset to
490 * dp->i_offset + dp->i_count.
492 if (ss.slotstatus == NONE) {
493 dp->i_offset = roundup2(dp->i_size, DIRBLKSIZ);
495 enduseful = dp->i_offset;
497 dp->i_offset = ss.slotoffset;
498 dp->i_count = ss.slotsize;
499 if (enduseful < ss.slotoffset + ss.slotsize)
500 enduseful = ss.slotoffset + ss.slotsize;
502 dp->i_endoff = roundup2(enduseful, DIRBLKSIZ);
504 * We return with the directory locked, so that
505 * the parameters we set up above will still be
506 * valid if we actually decide to do a direnter().
507 * We return ni_vp == NULL to indicate that the entry
508 * does not currently exist; we leave a pointer to
509 * the (locked) directory inode in ndp->ni_dvp.
510 * The pathname buffer is saved so that the name
511 * can be obtained later.
513 * NB - if the directory is unlocked, then this
514 * information cannot be used.
516 cnp->cn_flags |= SAVENAME;
517 return (EJUSTRETURN);
520 * Insert name into cache (as non-existent) if appropriate.
522 if ((cnp->cn_flags & MAKEENTRY) != 0)
523 cache_enter(vdp, NULL, cnp);
529 if (numdirpasses == 2)
530 nchstats.ncs_pass2++;
532 * Check that directory length properly reflects presence
535 if (entryoffsetinblock + EXT2_DIR_REC_LEN(ep->e2d_namlen)
537 ext2_dirbad(dp, i_offset, "i_size too small");
538 dp->i_size = entryoffsetinblock + EXT2_DIR_REC_LEN(ep->e2d_namlen);
539 dp->i_flag |= IN_CHANGE | IN_UPDATE;
544 * Found component in pathname.
545 * If the final component of path name, save information
546 * in the cache as to where the entry was found.
548 if ((flags & ISLASTCN) && nameiop == LOOKUP)
549 dp->i_diroff = rounddown2(i_offset, DIRBLKSIZ);
551 * If deleting, and at end of pathname, return
552 * parameters which can be used to remove file.
554 if (nameiop == DELETE && (flags & ISLASTCN)) {
555 if (flags & LOCKPARENT)
556 ASSERT_VOP_ELOCKED(vdp, __FUNCTION__);
558 * Write access to directory required to delete files.
560 if ((error = VOP_ACCESS(vdp, VWRITE, cred, cnp->cn_thread)) != 0)
563 * Return pointer to current entry in dp->i_offset,
564 * and distance past previous entry (if there
565 * is a previous entry in this block) in dp->i_count.
566 * Save directory inode pointer in ndp->ni_dvp for dirremove().
568 * Technically we shouldn't be setting these in the
569 * WANTPARENT case (first lookup in rename()), but any
570 * lookups that will result in directory changes will
573 dp->i_offset = i_offset;
574 if ((dp->i_offset & (DIRBLKSIZ - 1)) == 0)
577 dp->i_count = dp->i_offset - prevoff;
580 if (dp->i_number == ino) {
585 if ((error = VFS_VGET(vdp->v_mount, ino, LK_EXCLUSIVE,
589 * If directory is "sticky", then user must own
590 * the directory, or the file in it, else she
591 * may not delete it (unless she's root). This
592 * implements append-only directories.
594 if ((dp->i_mode & ISVTX) &&
596 cred->cr_uid != dp->i_uid &&
597 VTOI(tdp)->i_uid != cred->cr_uid) {
606 * If rewriting (RENAME), return the inode and the
607 * information required to rewrite the present directory
608 * Must get inode of directory entry to verify it's a
609 * regular file, or empty directory.
611 if (nameiop == RENAME && (flags & ISLASTCN)) {
612 if ((error = VOP_ACCESS(vdp, VWRITE, cred, cnp->cn_thread)) != 0)
615 * Careful about locking second inode.
616 * This can only occur if the target is ".".
618 dp->i_offset = i_offset;
619 if (dp->i_number == ino)
623 if ((error = VFS_VGET(vdp->v_mount, ino, LK_EXCLUSIVE,
627 cnp->cn_flags |= SAVENAME;
634 * Step through the translation in the name. We do not `vput' the
635 * directory because we may need it again if a symbolic link
636 * is relative to the current directory. Instead we save it
637 * unlocked as "pdp". We must get the target inode before unlocking
638 * the directory to insure that the inode will not be removed
639 * before we get it. We prevent deadlock by always fetching
640 * inodes from the root, moving down the directory tree. Thus
641 * when following backward pointers ".." we must unlock the
642 * parent directory before getting the requested directory.
643 * There is a potential race condition here if both the current
644 * and parent directories are removed before the VFS_VGET for the
645 * inode associated with ".." returns. We hope that this occurs
646 * infrequently since we cannot avoid this race condition without
647 * implementing a sophisticated deadlock detection algorithm.
648 * Note also that this simple deadlock detection scheme will not
649 * work if the file system has any hard links other than ".."
650 * that point backwards in the directory structure.
653 if (flags & ISDOTDOT) {
654 error = vn_vget_ino(pdp, ino, cnp->cn_lkflags, &tdp);
655 if (pdp->v_iflag & VI_DOOMED) {
663 * Recheck that ".." entry in the vdp directory points
664 * to the inode we looked up before vdp lock was
667 error = ext2_lookup_ino(pdp, NULL, cnp, &ino1);
677 } else if (dp->i_number == ino) {
678 VREF(vdp); /* we want ourself, ie "." */
680 * When we lookup "." we still can be asked to lock it
683 ltype = cnp->cn_lkflags & LK_TYPE_MASK;
684 if (ltype != VOP_ISLOCKED(vdp)) {
685 if (ltype == LK_EXCLUSIVE)
686 vn_lock(vdp, LK_UPGRADE | LK_RETRY);
687 else /* if (ltype == LK_SHARED) */
688 vn_lock(vdp, LK_DOWNGRADE | LK_RETRY);
692 if ((error = VFS_VGET(vdp->v_mount, ino, cnp->cn_lkflags,
699 * Insert name into cache if appropriate.
701 if (cnp->cn_flags & MAKEENTRY)
702 cache_enter(vdp, *vpp, cnp);
707 ext2_search_dirblock(struct inode *ip, void *data, int *foundp,
708 const char *name, int namelen, int *entryoffsetinblockp,
709 doff_t *offp, doff_t *prevoffp, doff_t *endusefulp,
710 struct ext2fs_searchslot *ssp)
713 struct ext2fs_direct_2 *ep, *top;
714 uint32_t bsize = ip->i_e2fs->e2fs_bsize;
715 int offset = *entryoffsetinblockp;
720 ep = (struct ext2fs_direct_2 *)((char *)data + offset);
721 top = (struct ext2fs_direct_2 *)((char *)data +
722 bsize - EXT2_DIR_REC_LEN(0));
726 * Full validation checks are slow, so we only check
727 * enough to insure forward progress through the
728 * directory. Complete checks can be run by setting
729 * "vfs.e2fs.dirchk" to be true.
731 if (ep->e2d_reclen == 0 ||
732 (dirchk && ext2_dirbadentry(vdp, ep, offset))) {
735 ext2_dirbad(ip, *offp, "mangled entry");
736 i = bsize - (offset & (bsize - 1));
743 * If an appropriate sized slot has not yet been found,
744 * check to see if one is available. Also accumulate space
745 * in the current block so that we can determine if
746 * compaction is viable.
748 if (ssp->slotstatus != FOUND) {
749 int size = ep->e2d_reclen;
751 if (ep->e2d_ino != 0)
752 size -= EXT2_DIR_REC_LEN(ep->e2d_namlen);
754 if (size >= ssp->slotneeded) {
755 ssp->slotstatus = FOUND;
756 ssp->slotoffset = *offp;
757 ssp->slotsize = ep->e2d_reclen;
758 } else if (ssp->slotstatus == NONE) {
759 ssp->slotfreespace += size;
760 if (ssp->slotoffset == -1)
761 ssp->slotoffset = *offp;
762 if (ssp->slotfreespace >= ssp->slotneeded) {
763 ssp->slotstatus = COMPACT;
764 ssp->slotsize = *offp +
772 * Check for a name match.
775 namlen = ep->e2d_namlen;
776 if (namlen == namelen &&
777 !bcmp(name, ep->e2d_name, (unsigned)namlen)) {
779 * Save directory entry's inode number and
780 * reclen in ndp->ni_ufs area, and release
788 *offp += ep->e2d_reclen;
789 offset += ep->e2d_reclen;
790 *entryoffsetinblockp = offset;
794 * Get pointer to the next entry.
796 ep = (struct ext2fs_direct_2 *)((char *)data + offset);
803 ext2_dirbad(struct inode *ip, doff_t offset, char *how)
807 mp = ITOV(ip)->v_mount;
808 if ((mp->mnt_flag & MNT_RDONLY) == 0)
809 panic("ext2_dirbad: %s: bad dir ino %ju at offset %ld: %s\n",
810 mp->mnt_stat.f_mntonname, (uintmax_t)ip->i_number,
813 (void)printf("%s: bad dir ino %ju at offset %ld: %s\n",
814 mp->mnt_stat.f_mntonname, (uintmax_t)ip->i_number,
820 * Do consistency checking on a directory entry:
821 * record length must be multiple of 4
822 * entry must fit in rest of its DIRBLKSIZ block
823 * record must be large enough to contain entry
824 * name is not longer than MAXNAMLEN
825 * name must be as long as advertised, and null terminated
828 * changed so that it confirms to ext2_check_dir_entry
831 ext2_dirbadentry(struct vnode *dp, struct ext2fs_direct_2 *de,
832 int entryoffsetinblock)
834 int DIRBLKSIZ = VTOI(dp)->i_e2fs->e2fs_bsize;
836 char *error_msg = NULL;
838 if (de->e2d_reclen < EXT2_DIR_REC_LEN(1))
839 error_msg = "rec_len is smaller than minimal";
840 else if (de->e2d_reclen % 4 != 0)
841 error_msg = "rec_len % 4 != 0";
842 else if (de->e2d_reclen < EXT2_DIR_REC_LEN(de->e2d_namlen))
843 error_msg = "reclen is too small for name_len";
844 else if (entryoffsetinblock + de->e2d_reclen > DIRBLKSIZ)
845 error_msg = "directory entry across blocks";
847 if (de->inode > dir->i_sb->u.ext2_sb.s_es->s_inodes_count)
848 error_msg = "inode out of bounds";
851 if (error_msg != NULL) {
852 printf("bad directory entry: %s\n", error_msg);
853 printf("offset=%d, inode=%lu, rec_len=%u, name_len=%u\n",
854 entryoffsetinblock, (unsigned long)de->e2d_ino,
855 de->e2d_reclen, de->e2d_namlen);
857 return error_msg == NULL ? 0 : 1;
861 * Write a directory entry after a call to namei, using the parameters
862 * that it left in nameidata. The argument ip is the inode which the new
863 * directory entry will refer to. Dvp is a pointer to the directory to
864 * be written, which was left locked by namei. Remaining parameters
865 * (dp->i_offset, dp->i_count) indicate how the space for the new
866 * entry is to be obtained.
869 ext2_direnter(struct inode *ip, struct vnode *dvp, struct componentname *cnp)
872 struct ext2fs_direct_2 newdir;
874 int DIRBLKSIZ = ip->i_e2fs->e2fs_bsize;
879 if ((cnp->cn_flags & SAVENAME) == 0)
880 panic("ext2_direnter: missing name");
883 newdir.e2d_ino = ip->i_number;
884 newdir.e2d_namlen = cnp->cn_namelen;
885 if (EXT2_HAS_INCOMPAT_FEATURE(ip->i_e2fs,
886 EXT2F_INCOMPAT_FTYPE))
887 newdir.e2d_type = DTTOFT(IFTODT(ip->i_mode));
889 newdir.e2d_type = EXT2_FT_UNKNOWN;
890 bcopy(cnp->cn_nameptr, newdir.e2d_name, (unsigned)cnp->cn_namelen + 1);
892 if (ext2_htree_has_idx(dp)) {
893 error = ext2_htree_add_entry(dvp, &newdir, cnp);
895 dp->i_flag &= ~IN_E3INDEX;
896 dp->i_flag |= IN_CHANGE | IN_UPDATE;
901 if (EXT2_HAS_COMPAT_FEATURE(ip->i_e2fs, EXT2F_COMPAT_DIRHASHINDEX) &&
902 !ext2_htree_has_idx(dp)) {
903 if ((dp->i_size / DIRBLKSIZ) == 1 &&
904 dp->i_offset == DIRBLKSIZ) {
906 * Making indexed directory when one block is not
907 * enough to save all entries.
909 return ext2_htree_create_index(dvp, cnp, &newdir);
913 if (dp->i_count == 0) {
915 * If dp->i_count is 0, then namei could find no
916 * space in the directory. Here, dp->i_offset will
917 * be on a directory block boundary and we will write the
918 * new entry into a fresh block.
920 if (dp->i_offset & (DIRBLKSIZ - 1))
921 panic("ext2_direnter: newblk");
923 newdir.e2d_reclen = DIRBLKSIZ;
925 bp = getblk(ip->i_devvp, lblkno(dp->i_e2fs, dp->i_offset),
930 memcpy(bp->b_data, &newdir, sizeof(struct ext2fs_direct_2));
932 ext2_dir_blk_csum_set(dp, bp);
937 dp->i_size = roundup2(dp->i_size, DIRBLKSIZ);
938 dp->i_flag |= IN_CHANGE;
943 error = ext2_add_entry(dvp, &newdir);
944 if (!error && dp->i_endoff && dp->i_endoff < dp->i_size)
945 error = ext2_truncate(dvp, (off_t)dp->i_endoff, IO_SYNC,
946 cnp->cn_cred, cnp->cn_thread);
951 * Insert an entry into the directory block.
952 * Compact the contents.
955 ext2_add_entry(struct vnode *dvp, struct ext2fs_direct_2 *entry)
957 struct ext2fs_direct_2 *ep, *nep;
961 int error, loc, newentrysize, spacefree;
967 * If dp->i_count is non-zero, then namei found space
968 * for the new entry in the range dp->i_offset to
969 * dp->i_offset + dp->i_count in the directory.
970 * To use this space, we may have to compact the entries located
971 * there, by copying them together towards the beginning of the
972 * block, leaving the free space in one usable chunk at the end.
976 * Increase size of directory if entry eats into new space.
977 * This should never push the size past a new multiple of
980 * N.B. - THIS IS AN ARTIFACT OF 4.2 AND SHOULD NEVER HAPPEN.
982 if (dp->i_offset + dp->i_count > dp->i_size)
983 dp->i_size = dp->i_offset + dp->i_count;
985 * Get the block containing the space for the new directory entry.
987 if ((error = ext2_blkatoff(dvp, (off_t)dp->i_offset, &dirbuf,
991 * Find space for the new entry. In the simple case, the entry at
992 * offset base will have the space. If it does not, then namei
993 * arranged that compacting the region dp->i_offset to
994 * dp->i_offset + dp->i_count would yield the
997 newentrysize = EXT2_DIR_REC_LEN(entry->e2d_namlen);
998 ep = (struct ext2fs_direct_2 *)dirbuf;
999 dsize = EXT2_DIR_REC_LEN(ep->e2d_namlen);
1000 spacefree = ep->e2d_reclen - dsize;
1001 for (loc = ep->e2d_reclen; loc < dp->i_count; ) {
1002 nep = (struct ext2fs_direct_2 *)(dirbuf + loc);
1004 /* trim the existing slot */
1005 ep->e2d_reclen = dsize;
1006 ep = (struct ext2fs_direct_2 *)((char *)ep + dsize);
1008 /* overwrite; nothing there; header is ours */
1011 dsize = EXT2_DIR_REC_LEN(nep->e2d_namlen);
1012 spacefree += nep->e2d_reclen - dsize;
1013 loc += nep->e2d_reclen;
1014 bcopy((caddr_t)nep, (caddr_t)ep, dsize);
1017 * Update the pointer fields in the previous entry (if any),
1018 * copy in the new entry, and write out the block.
1020 if (ep->e2d_ino == 0) {
1021 if (spacefree + dsize < newentrysize)
1022 panic("ext2_direnter: compact1");
1023 entry->e2d_reclen = spacefree + dsize;
1025 if (spacefree < newentrysize)
1026 panic("ext2_direnter: compact2");
1027 entry->e2d_reclen = spacefree;
1028 ep->e2d_reclen = dsize;
1029 ep = (struct ext2fs_direct_2 *)((char *)ep + dsize);
1031 bcopy((caddr_t)entry, (caddr_t)ep, (u_int)newentrysize);
1032 ext2_dir_blk_csum_set(dp, bp);
1033 if (DOINGASYNC(dvp)) {
1039 dp->i_flag |= IN_CHANGE | IN_UPDATE;
1044 * Remove a directory entry after a call to namei, using
1045 * the parameters which it left in nameidata. The entry
1046 * dp->i_offset contains the offset into the directory of the
1047 * entry to be eliminated. The dp->i_count field contains the
1048 * size of the previous record in the directory. If this
1049 * is 0, the first entry is being deleted, so we need only
1050 * zero the inode number to mark the entry as free. If the
1051 * entry is not the first in the directory, we must reclaim
1052 * the space of the now empty record by adding the record size
1053 * to the size of the previous entry.
1056 ext2_dirremove(struct vnode *dvp, struct componentname *cnp)
1059 struct ext2fs_direct_2 *ep, *rep;
1064 if (dp->i_count == 0) {
1066 * First entry in block: set d_ino to zero.
1069 ext2_blkatoff(dvp, (off_t)dp->i_offset, (char **)&ep,
1074 dp->i_flag |= IN_CHANGE | IN_UPDATE;
1078 * Collapse new free space into previous entry.
1080 if ((error = ext2_blkatoff(dvp, (off_t)(dp->i_offset - dp->i_count),
1081 (char **)&ep, &bp)) != 0)
1084 /* Set 'rep' to the entry being removed. */
1085 if (dp->i_count == 0)
1088 rep = (struct ext2fs_direct_2 *)((char *)ep + ep->e2d_reclen);
1089 ep->e2d_reclen += rep->e2d_reclen;
1090 ext2_dir_blk_csum_set(dp, bp);
1091 if (DOINGASYNC(dvp) && dp->i_count != 0)
1095 dp->i_flag |= IN_CHANGE | IN_UPDATE;
1100 * Rewrite an existing directory entry to point at the inode
1101 * supplied. The parameters describing the directory entry are
1102 * set up by a call to namei.
1105 ext2_dirrewrite(struct inode *dp, struct inode *ip, struct componentname *cnp)
1108 struct ext2fs_direct_2 *ep;
1109 struct vnode *vdp = ITOV(dp);
1112 if ((error = ext2_blkatoff(vdp, (off_t)dp->i_offset, (char **)&ep,
1115 ep->e2d_ino = ip->i_number;
1116 if (EXT2_HAS_INCOMPAT_FEATURE(ip->i_e2fs,
1117 EXT2F_INCOMPAT_FTYPE))
1118 ep->e2d_type = DTTOFT(IFTODT(ip->i_mode));
1120 ep->e2d_type = EXT2_FT_UNKNOWN;
1121 ext2_dir_blk_csum_set(dp, bp);
1123 dp->i_flag |= IN_CHANGE | IN_UPDATE;
1128 * Check if a directory is empty or not.
1129 * Inode supplied must be locked.
1131 * Using a struct dirtemplate here is not precisely
1132 * what we want, but better than using a struct direct.
1134 * NB: does not handle corrupted directories.
1137 ext2_dirempty(struct inode *ip, ino_t parentino, struct ucred *cred)
1140 struct dirtemplate dbuf;
1141 struct ext2fs_direct_2 *dp = (struct ext2fs_direct_2 *)&dbuf;
1144 #define MINDIRSIZ (sizeof(struct dirtemplate) / 2)
1146 for (off = 0; off < ip->i_size; off += dp->e2d_reclen) {
1147 error = vn_rdwr(UIO_READ, ITOV(ip), (caddr_t)dp, MINDIRSIZ,
1148 off, UIO_SYSSPACE, IO_NODELOCKED | IO_NOMACCHECK, cred,
1149 NOCRED, &count, (struct thread *)0);
1151 * Since we read MINDIRSIZ, residual must
1152 * be 0 unless we're at end of file.
1154 if (error || count != 0)
1156 /* avoid infinite loops */
1157 if (dp->e2d_reclen == 0)
1159 /* skip empty entries */
1160 if (dp->e2d_ino == 0)
1162 /* accept only "." and ".." */
1163 namlen = dp->e2d_namlen;
1166 if (dp->e2d_name[0] != '.')
1169 * At this point namlen must be 1 or 2.
1170 * 1 implies ".", 2 implies ".." if second
1175 if (dp->e2d_name[1] == '.' && dp->e2d_ino == parentino)
1183 * Check if source directory is in the path of the target directory.
1184 * Target is supplied locked, source is unlocked.
1185 * The target is always vput before returning.
1188 ext2_checkpath(struct inode *source, struct inode *target, struct ucred *cred)
1192 struct dirtemplate dirbuf;
1195 if (target->i_number == source->i_number) {
1199 if (target->i_number == EXT2_ROOTINO) {
1205 if (vp->v_type != VDIR) {
1209 error = vn_rdwr(UIO_READ, vp, (caddr_t)&dirbuf,
1210 sizeof(struct dirtemplate), (off_t)0, UIO_SYSSPACE,
1211 IO_NODELOCKED | IO_NOMACCHECK, cred, NOCRED, NULL,
1215 namlen = dirbuf.dotdot_type; /* like ufs little-endian */
1217 dirbuf.dotdot_name[0] != '.' ||
1218 dirbuf.dotdot_name[1] != '.') {
1222 if (dirbuf.dotdot_ino == source->i_number) {
1226 if (dirbuf.dotdot_ino == EXT2_ROOTINO)
1229 if ((error = VFS_VGET(vp->v_mount, dirbuf.dotdot_ino,
1230 LK_EXCLUSIVE, &vp)) != 0) {
1237 if (error == ENOTDIR)
1238 printf("checkpath: .. not a directory\n");