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
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/namei.h>
50 #include <sys/endian.h>
51 #include <sys/mount.h>
52 #include <sys/vnode.h>
53 #include <sys/malloc.h>
54 #include <sys/dirent.h>
56 #include <sys/sysctl.h>
58 #include <ufs/ufs/dir.h>
60 #include <fs/ext2fs/fs.h>
61 #include <fs/ext2fs/inode.h>
62 #include <fs/ext2fs/ext2_mount.h>
63 #include <fs/ext2fs/ext2fs.h>
64 #include <fs/ext2fs/ext2_dinode.h>
65 #include <fs/ext2fs/ext2_dir.h>
66 #include <fs/ext2fs/ext2_extern.h>
67 #include <fs/ext2fs/fs.h>
69 SDT_PROVIDER_DECLARE(ext2fs);
72 * arg0: verbosity. Higher numbers give more verbose messages
73 * arg1: Textual message
75 SDT_PROBE_DEFINE2(ext2fs, , lookup, trace, "int", "char*");
76 SDT_PROBE_DEFINE4(ext2fs, , trace, ext2_dirbad_error,
77 "char*", "ino_t", "doff_t", "char*");
78 SDT_PROBE_DEFINE5(ext2fs, , trace, ext2_dirbadentry_error,
79 "char*", "int", "uint32_t", "uint16_t", "uint8_t");
81 static SYSCTL_NODE(_vfs, OID_AUTO, e2fs, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
85 DIRBLKSIZE in ffs is DEV_BSIZE (in most cases 512)
86 while it is the native blocksize in ext2fs - thus, a #define
87 is no longer appropriate
91 static u_char ext2_ft_to_dt[] = {
92 DT_UNKNOWN, /* EXT2_FT_UNKNOWN */
93 DT_REG, /* EXT2_FT_REG_FILE */
94 DT_DIR, /* EXT2_FT_DIR */
95 DT_CHR, /* EXT2_FT_CHRDEV */
96 DT_BLK, /* EXT2_FT_BLKDEV */
97 DT_FIFO, /* EXT2_FT_FIFO */
98 DT_SOCK, /* EXT2_FT_SOCK */
99 DT_LNK, /* EXT2_FT_SYMLINK */
102 ((ft) < nitems(ext2_ft_to_dt) ? ext2_ft_to_dt[(ft)] : DT_UNKNOWN)
104 static u_char dt_to_ext2_ft[] = {
105 EXT2_FT_UNKNOWN, /* DT_UNKNOWN */
106 EXT2_FT_FIFO, /* DT_FIFO */
107 EXT2_FT_CHRDEV, /* DT_CHR */
108 EXT2_FT_UNKNOWN, /* unused */
109 EXT2_FT_DIR, /* DT_DIR */
110 EXT2_FT_UNKNOWN, /* unused */
111 EXT2_FT_BLKDEV, /* DT_BLK */
112 EXT2_FT_UNKNOWN, /* unused */
113 EXT2_FT_REG_FILE, /* DT_REG */
114 EXT2_FT_UNKNOWN, /* unused */
115 EXT2_FT_SYMLINK, /* DT_LNK */
116 EXT2_FT_UNKNOWN, /* unused */
117 EXT2_FT_SOCK, /* DT_SOCK */
118 EXT2_FT_UNKNOWN, /* unused */
119 EXT2_FT_UNKNOWN, /* DT_WHT */
122 ((dt) < nitems(dt_to_ext2_ft) ? dt_to_ext2_ft[(dt)] : EXT2_FT_UNKNOWN)
124 static int ext2_check_direntry(struct vnode *dp,
125 struct ext2fs_direct_2 *de, int entryoffsetinblock);
126 static int ext2_is_dot_entry(struct componentname *cnp);
127 static int ext2_lookup_ino(struct vnode *vdp, struct vnode **vpp,
128 struct componentname *cnp, ino_t *dd_ino);
131 ext2_is_dot_entry(struct componentname *cnp)
133 if (cnp->cn_namelen <= 2 && cnp->cn_nameptr[0] == '.' &&
134 (cnp->cn_nameptr[1] == '.' || cnp->cn_nameptr[1] == '\0'))
140 * Vnode op for reading directories.
143 ext2_readdir(struct vop_readdir_args *ap)
145 struct vnode *vp = ap->a_vp;
146 struct uio *uio = ap->a_uio;
149 struct ext2fs_direct_2 *dp, *edp;
152 off_t offset, startoffset;
153 size_t readcnt, skipcnt;
156 int DIRBLKSIZ = VTOI(ap->a_vp)->i_e2fs->e2fs_bsize;
159 if (uio->uio_offset < 0)
162 if (ap->a_ncookies != NULL) {
163 if (uio->uio_resid < 0)
166 ncookies = uio->uio_resid;
167 if (uio->uio_offset >= ip->i_size)
169 else if (ip->i_size - uio->uio_offset < ncookies)
170 ncookies = ip->i_size - uio->uio_offset;
171 ncookies = ncookies / (offsetof(struct ext2fs_direct_2,
172 e2d_namlen) + 4) + 1;
173 cookies = malloc(ncookies * sizeof(*cookies), M_TEMP, M_WAITOK);
174 *ap->a_ncookies = ncookies;
175 *ap->a_cookies = cookies;
180 offset = startoffset = uio->uio_offset;
181 startresid = uio->uio_resid;
183 while (error == 0 && uio->uio_resid > 0 &&
184 uio->uio_offset < ip->i_size) {
185 error = ext2_blkatoff(vp, uio->uio_offset, NULL, &bp);
188 if (bp->b_offset + bp->b_bcount > ip->i_size)
189 readcnt = ip->i_size - bp->b_offset;
191 readcnt = bp->b_bcount;
192 skipcnt = (size_t)(uio->uio_offset - bp->b_offset) &
193 ~(size_t)(DIRBLKSIZ - 1);
194 offset = bp->b_offset + skipcnt;
195 dp = (struct ext2fs_direct_2 *)&bp->b_data[skipcnt];
196 edp = (struct ext2fs_direct_2 *)&bp->b_data[readcnt];
197 while (error == 0 && uio->uio_resid > 0 && dp < edp) {
198 if (le16toh(dp->e2d_reclen) <= offsetof(struct ext2fs_direct_2,
199 e2d_namlen) || (caddr_t)dp + le16toh(dp->e2d_reclen) >
205 * "New" ext2fs directory entries differ in 3 ways
206 * from ufs on-disk ones:
207 * - the name is not necessarily NUL-terminated.
208 * - the file type field always exists and always
209 * follows the name length field.
210 * - the file type is encoded in a different way.
212 * "Old" ext2fs directory entries need no special
213 * conversions, since they are binary compatible
214 * with "new" entries having a file type of 0 (i.e.,
215 * EXT2_FT_UNKNOWN). Splitting the old name length
216 * field didn't make a mess like it did in ufs,
217 * because ext2fs uses a machine-independent disk
220 dstdp.d_namlen = dp->e2d_namlen;
221 dstdp.d_type = FTTODT(dp->e2d_type);
222 if (offsetof(struct ext2fs_direct_2, e2d_namlen) +
223 dstdp.d_namlen > le16toh(dp->e2d_reclen)) {
227 if (offset < startoffset || le32toh(dp->e2d_ino) == 0)
229 dstdp.d_fileno = le32toh(dp->e2d_ino);
230 dstdp.d_reclen = GENERIC_DIRSIZ(&dstdp);
231 bcopy(dp->e2d_name, dstdp.d_name, dstdp.d_namlen);
232 /* NOTE: d_off is the offset of the *next* entry. */
233 dstdp.d_off = offset + le16toh(dp->e2d_reclen);
234 dirent_terminate(&dstdp);
235 if (dstdp.d_reclen > uio->uio_resid) {
236 if (uio->uio_resid == startresid)
243 error = uiomove((caddr_t)&dstdp, dstdp.d_reclen, uio);
246 if (cookies != NULL) {
247 KASSERT(ncookies > 0,
248 ("ext2_readdir: cookies buffer too small"));
249 *cookies = offset + le16toh(dp->e2d_reclen);
254 offset += le16toh(dp->e2d_reclen);
255 dp = (struct ext2fs_direct_2 *)((caddr_t)dp +
256 le16toh(dp->e2d_reclen));
259 uio->uio_offset = offset;
261 /* We need to correct uio_offset. */
262 uio->uio_offset = offset;
263 if (error == EJUSTRETURN)
265 if (ap->a_ncookies != NULL) {
267 *ap->a_ncookies -= ncookies;
269 free(*ap->a_cookies, M_TEMP);
271 *ap->a_cookies = NULL;
274 if (error == 0 && ap->a_eofflag)
275 *ap->a_eofflag = ip->i_size <= uio->uio_offset;
280 * Convert a component of a pathname into a pointer to a locked inode.
281 * This is a very central and rather complicated routine.
282 * If the file system is not maintained in a strict tree hierarchy,
283 * this can result in a deadlock situation (see comments in code below).
285 * The cnp->cn_nameiop argument is LOOKUP, CREATE, RENAME, or DELETE depending
286 * on whether the name is to be looked up, created, renamed, or deleted.
287 * When CREATE, RENAME, or DELETE is specified, information usable in
288 * creating, renaming, or deleting a directory entry may be calculated.
289 * If flag has LOCKPARENT or'ed into it and the target of the pathname
290 * exists, lookup returns both the target and its parent directory locked.
291 * When creating or renaming and LOCKPARENT is specified, the target may
292 * not be ".". When deleting and LOCKPARENT is specified, the target may
293 * be "."., but the caller must check to ensure it does an vrele and vput
294 * instead of two vputs.
296 * Overall outline of ext2_lookup:
298 * search for name in directory, to found or notfound
300 * if creating, return locked directory, leaving info on available slots
303 * if at end of path and deleting, return information to allow delete
304 * if at end of path and rewriting (RENAME and LOCKPARENT), lock target
305 * inode and return info to allow rewrite
306 * if not at end, add name to cache; if at end and neither creating
307 * nor deleting, add name to cache
310 ext2_lookup(struct vop_cachedlookup_args *ap)
313 return (ext2_lookup_ino(ap->a_dvp, ap->a_vpp, ap->a_cnp, NULL));
317 ext2_lookup_ino(struct vnode *vdp, struct vnode **vpp, struct componentname *cnp,
320 struct inode *dp; /* inode for directory being searched */
321 struct buf *bp; /* a buffer of directory entries */
322 struct ext2fs_direct_2 *ep; /* the current directory entry */
323 int entryoffsetinblock; /* offset of ep in bp's buffer */
324 struct ext2fs_searchslot ss;
325 doff_t i_diroff; /* cached i_diroff value */
326 doff_t i_offset; /* cached i_offset value */
327 int numdirpasses; /* strategy for directory search */
328 doff_t endsearch; /* offset to end directory search */
329 doff_t prevoff; /* prev entry dp->i_offset */
330 struct vnode *pdp; /* saved dp during symlink work */
331 struct vnode *tdp; /* returned by VFS_VGET */
332 doff_t enduseful; /* pointer past last used dir slot */
333 u_long bmask; /* block offset mask */
335 struct ucred *cred = cnp->cn_cred;
336 int flags = cnp->cn_flags;
337 int nameiop = cnp->cn_nameiop;
342 int DIRBLKSIZ = VTOI(vdp)->i_e2fs->e2fs_bsize;
348 bmask = VFSTOEXT2(vdp->v_mount)->um_mountp->mnt_stat.f_iosize - 1;
354 * We now have a segment name to search for, and a directory to search.
356 * Suppress search for slots unless creating
357 * file and at end of pathname, in which case
358 * we watch for a place to put the new file in
359 * case it doesn't already exist.
361 i_diroff = dp->i_diroff;
362 ss.slotstatus = FOUND;
363 ss.slotfreespace = ss.slotsize = ss.slotneeded = 0;
364 if ((nameiop == CREATE || nameiop == RENAME) &&
365 (flags & ISLASTCN)) {
366 ss.slotstatus = NONE;
367 ss.slotneeded = EXT2_DIR_REC_LEN(cnp->cn_namelen);
369 * was ss.slotneeded = (sizeof(struct direct) - MAXNAMLEN +
370 * cnp->cn_namelen + 3) &~ 3;
374 * Try to lookup dir entry using htree directory index.
376 * If we got an error or we want to find '.' or '..' entry,
377 * we will fall back to linear search.
379 if (!ext2_is_dot_entry(cnp) && ext2_htree_has_idx(dp)) {
381 entryoffsetinblock = 0;
382 switch (ext2_htree_lookup(dp, cnp->cn_nameptr, cnp->cn_namelen,
383 &bp, &entryoffsetinblock, &i_offset, &prevoff,
386 ep = (struct ext2fs_direct_2 *)((char *)bp->b_data +
390 i_offset = roundup2(dp->i_size, DIRBLKSIZ);
394 * Something failed; just fallback to do a linear
402 * If there is cached information on a previous search of
403 * this directory, pick up where we last left off.
404 * We cache only lookups as these are the most common
405 * and have the greatest payoff. Caching CREATE has little
406 * benefit as it usually must search the entire directory
407 * to determine that the entry does not exist. Caching the
408 * location of the last DELETE or RENAME has not reduced
409 * profiling time and hence has been removed in the interest
412 if (nameiop != LOOKUP || i_diroff == 0 ||
413 i_diroff > dp->i_size) {
414 entryoffsetinblock = 0;
419 if ((entryoffsetinblock = i_offset & bmask) &&
420 (error = ext2_blkatoff(vdp, (off_t)i_offset, NULL,
424 nchstats.ncs_2passes++;
427 endsearch = roundup2(dp->i_size, DIRBLKSIZ);
431 while (i_offset < endsearch) {
433 * If necessary, get the next directory block.
437 error = ext2_blkatoff(vdp, (off_t)i_offset, NULL, &bp);
441 entryoffsetinblock = 0;
442 if (ss.slotstatus == NONE) {
444 ss.slotfreespace = 0;
447 error = ext2_search_dirblock(dp, bp->b_data, &entry_found,
448 cnp->cn_nameptr, cnp->cn_namelen,
449 &entryoffsetinblock, &i_offset, &prevoff,
456 ep = (struct ext2fs_direct_2 *)((char *)bp->b_data +
457 (entryoffsetinblock & bmask));
459 ino = le32toh(ep->e2d_ino);
465 * If we started in the middle of the directory and failed
466 * to find our target, we must check the beginning as well.
468 if (numdirpasses == 2) {
471 endsearch = i_diroff;
477 * If creating, and at end of pathname and current
478 * directory has not been removed, then can consider
479 * allowing file to be created.
481 if ((nameiop == CREATE || nameiop == RENAME) &&
482 (flags & ISLASTCN) && dp->i_nlink != 0) {
484 * Access for write is interpreted as allowing
485 * creation of files in the directory.
487 if ((error = VOP_ACCESS(vdp, VWRITE, cred, curthread)) != 0)
490 * Return an indication of where the new directory
491 * entry should be put. If we didn't find a slot,
492 * then set dp->i_count to 0 indicating
493 * that the new slot belongs at the end of the
494 * directory. If we found a slot, then the new entry
495 * can be put in the range from dp->i_offset to
496 * dp->i_offset + dp->i_count.
498 if (ss.slotstatus == NONE) {
499 dp->i_offset = roundup2(dp->i_size, DIRBLKSIZ);
501 enduseful = dp->i_offset;
503 dp->i_offset = ss.slotoffset;
504 dp->i_count = ss.slotsize;
505 if (enduseful < ss.slotoffset + ss.slotsize)
506 enduseful = ss.slotoffset + ss.slotsize;
508 dp->i_endoff = roundup2(enduseful, DIRBLKSIZ);
510 * We return with the directory locked, so that
511 * the parameters we set up above will still be
512 * valid if we actually decide to do a direnter().
513 * We return ni_vp == NULL to indicate that the entry
514 * does not currently exist; we leave a pointer to
515 * the (locked) directory inode in ndp->ni_dvp.
517 * NB - if the directory is unlocked, then this
518 * information cannot be used.
520 return (EJUSTRETURN);
523 * Insert name into cache (as non-existent) if appropriate.
525 if ((cnp->cn_flags & MAKEENTRY) != 0)
526 cache_enter(vdp, NULL, cnp);
532 if (numdirpasses == 2)
533 nchstats.ncs_pass2++;
535 * Check that directory length properly reflects presence
538 if (entryoffsetinblock + EXT2_DIR_REC_LEN(ep->e2d_namlen) >
540 ext2_dirbad(dp, i_offset, "i_size too small");
547 * Found component in pathname.
548 * If the final component of path name, save information
549 * in the cache as to where the entry was found.
551 if ((flags & ISLASTCN) && nameiop == LOOKUP)
552 dp->i_diroff = rounddown2(i_offset, DIRBLKSIZ);
554 * If deleting, and at end of pathname, return
555 * parameters which can be used to remove file.
557 if (nameiop == DELETE && (flags & ISLASTCN)) {
558 if (flags & LOCKPARENT)
559 ASSERT_VOP_ELOCKED(vdp, __FUNCTION__);
561 * Write access to directory required to delete files.
563 if ((error = VOP_ACCESS(vdp, VWRITE, cred, curthread)) != 0)
566 * Return pointer to current entry in dp->i_offset,
567 * and distance past previous entry (if there
568 * is a previous entry in this block) in dp->i_count.
569 * Save directory inode pointer in ndp->ni_dvp for dirremove().
571 * Technically we shouldn't be setting these in the
572 * WANTPARENT case (first lookup in rename()), but any
573 * lookups that will result in directory changes will
576 dp->i_offset = i_offset;
577 if ((dp->i_offset & (DIRBLKSIZ - 1)) == 0)
580 dp->i_count = dp->i_offset - prevoff;
583 if (dp->i_number == ino) {
588 if ((error = VFS_VGET(vdp->v_mount, ino, LK_EXCLUSIVE,
592 * If directory is "sticky", then user must own
593 * the directory, or the file in it, else she
594 * may not delete it (unless she's root). This
595 * implements append-only directories.
597 if ((dp->i_mode & ISVTX) &&
599 cred->cr_uid != dp->i_uid &&
600 VTOI(tdp)->i_uid != cred->cr_uid) {
609 * If rewriting (RENAME), return the inode and the
610 * information required to rewrite the present directory
611 * Must get inode of directory entry to verify it's a
612 * regular file, or empty directory.
614 if (nameiop == RENAME && (flags & ISLASTCN)) {
615 if ((error = VOP_ACCESS(vdp, VWRITE, cred, curthread)) != 0)
618 * Careful about locking second inode.
619 * This can only occur if the target is ".".
621 dp->i_offset = i_offset;
622 if (dp->i_number == ino)
626 if ((error = VFS_VGET(vdp->v_mount, ino, LK_EXCLUSIVE,
636 * Step through the translation in the name. We do not `vput' the
637 * directory because we may need it again if a symbolic link
638 * is relative to the current directory. Instead we save it
639 * unlocked as "pdp". We must get the target inode before unlocking
640 * the directory to insure that the inode will not be removed
641 * before we get it. We prevent deadlock by always fetching
642 * inodes from the root, moving down the directory tree. Thus
643 * when following backward pointers ".." we must unlock the
644 * parent directory before getting the requested directory.
645 * There is a potential race condition here if both the current
646 * and parent directories are removed before the VFS_VGET for the
647 * inode associated with ".." returns. We hope that this occurs
648 * infrequently since we cannot avoid this race condition without
649 * implementing a sophisticated deadlock detection algorithm.
650 * Note also that this simple deadlock detection scheme will not
651 * work if the file system has any hard links other than ".."
652 * that point backwards in the directory structure.
655 if (flags & ISDOTDOT) {
656 error = vn_vget_ino(pdp, ino, cnp->cn_lkflags, &tdp);
657 if (VN_IS_DOOMED(pdp)) {
665 * Recheck that ".." entry in the vdp directory points
666 * to the inode we looked up before vdp lock was
669 error = ext2_lookup_ino(pdp, NULL, cnp, &ino1);
679 } else if (dp->i_number == ino) {
680 VREF(vdp); /* we want ourself, ie "." */
682 * When we lookup "." we still can be asked to lock it
685 ltype = cnp->cn_lkflags & LK_TYPE_MASK;
686 if (ltype != VOP_ISLOCKED(vdp)) {
687 if (ltype == LK_EXCLUSIVE)
688 vn_lock(vdp, LK_UPGRADE | LK_RETRY);
689 else /* if (ltype == LK_SHARED) */
690 vn_lock(vdp, LK_DOWNGRADE | LK_RETRY);
694 if ((error = VFS_VGET(vdp->v_mount, ino, cnp->cn_lkflags,
701 * Insert name into cache if appropriate.
703 if (cnp->cn_flags & MAKEENTRY)
704 cache_enter(vdp, *vpp, cnp);
709 ext2_search_dirblock(struct inode *ip, void *data, int *foundp,
710 const char *name, int namelen, int *entryoffsetinblockp,
711 doff_t *offp, doff_t *prevoffp, doff_t *endusefulp,
712 struct ext2fs_searchslot *ssp)
715 struct ext2fs_direct_2 *ep, *top;
716 uint32_t bsize = ip->i_e2fs->e2fs_bsize;
717 int offset = *entryoffsetinblockp;
722 ep = (struct ext2fs_direct_2 *)((char *)data + offset);
723 top = (struct ext2fs_direct_2 *)((char *)data + bsize);
725 if (ext2_check_direntry(vdp, ep, offset)) {
728 ext2_dirbad(ip, *offp, "mangled entry");
729 i = bsize - (offset & (bsize - 1));
732 ep = (struct ext2fs_direct_2 *)((char *)data + offset);
737 * If an appropriate sized slot has not yet been found,
738 * check to see if one is available. Also accumulate space
739 * in the current block so that we can determine if
740 * compaction is viable.
742 if (ssp->slotstatus != FOUND) {
743 int size = le16toh(ep->e2d_reclen);
745 if (ep->e2d_ino != 0)
746 size -= EXT2_DIR_REC_LEN(ep->e2d_namlen);
747 else if (ext2_is_dirent_tail(ip, ep))
748 size -= sizeof(struct ext2fs_direct_tail);
750 if (size >= ssp->slotneeded) {
751 ssp->slotstatus = FOUND;
752 ssp->slotoffset = *offp;
753 ssp->slotsize = le16toh(ep->e2d_reclen);
754 } else if (ssp->slotstatus == NONE) {
755 ssp->slotfreespace += size;
756 if (ssp->slotoffset == -1)
757 ssp->slotoffset = *offp;
758 if (ssp->slotfreespace >= ssp->slotneeded) {
759 ssp->slotstatus = COMPACT;
760 ssp->slotsize = *offp +
761 le16toh(ep->e2d_reclen) -
768 * Check for a name match.
770 if (ep->e2d_ino != 0) {
771 namlen = ep->e2d_namlen;
772 if (namlen == namelen &&
773 !bcmp(name, ep->e2d_name, (unsigned)namlen)) {
775 * Save directory entry's inode number and
776 * reclen in ndp->ni_ufs area, and release
784 *offp += le16toh(ep->e2d_reclen);
785 offset += le16toh(ep->e2d_reclen);
786 *entryoffsetinblockp = offset;
787 if (ep->e2d_ino != 0)
790 * Get pointer to the next entry.
792 ep = (struct ext2fs_direct_2 *)((char *)data + offset);
799 ext2_dirbad(struct inode *ip, doff_t offset, char *how)
802 SDT_PROBE4(ext2fs, , trace, ext2_dirbad_error,
803 ITOV(ip)->v_mount->mnt_stat.f_mntonname, ip->i_number, offset, how);
807 * Do consistency checking on a directory entry:
808 * record length must be multiple of 4
809 * entry must fit in rest of its DIRBLKSIZ block
810 * record must be large enough to contain entry
811 * name is not longer than MAXNAMLEN
812 * name must be as long as advertised, and null terminated
813 * inode number less then inode count
814 * if root inode entry, it have correct name
817 ext2_check_direntry(struct vnode *dp, struct ext2fs_direct_2 *de,
818 int entryoffsetinblock)
820 struct m_ext2fs *fs = VTOI(dp)->i_e2fs;
821 char *error_msg = NULL;
823 if (le16toh(de->e2d_reclen) < EXT2_DIR_REC_LEN(1))
824 error_msg = "rec_len is smaller than minimal";
825 else if (le16toh(de->e2d_reclen) % 4 != 0)
826 error_msg = "rec_len % 4 != 0";
827 else if (le16toh(de->e2d_reclen) < EXT2_DIR_REC_LEN(de->e2d_namlen))
828 error_msg = "reclen is too small for name_len";
829 else if (entryoffsetinblock + le16toh(de->e2d_reclen)> fs->e2fs_bsize)
830 error_msg = "directory entry across blocks";
831 else if (le32toh(de->e2d_ino) > fs->e2fs->e2fs_icount)
832 error_msg = "directory entry inode out of bounds";
833 else if (le32toh(de->e2d_ino) == EXT2_ROOTINO &&
834 ((de->e2d_namlen != 1 && de->e2d_namlen != 2) ||
835 (de->e2d_name[0] != '.') ||
836 (de->e2d_namlen == 2 && de->e2d_name[1] != '.')))
837 error_msg = "bad root directory entry";
839 if (error_msg != NULL) {
840 SDT_PROBE5(ext2fs, , trace, ext2_dirbadentry_error,
841 error_msg, entryoffsetinblock,
842 le32toh(de->e2d_ino), le16toh(de->e2d_reclen),
845 return (error_msg == NULL ? 0 : EINVAL);
849 * Insert an entry into the fresh directory block.
850 * Initialize entry tail if the metadata_csum feature is turned on.
853 ext2_add_first_entry(struct vnode *dvp, struct ext2fs_direct_2 *entry,
854 struct componentname *cnp)
860 int dirblksize, error;
863 dirblksize = dp->i_e2fs->e2fs_bsize;
865 if (dp->i_offset & (dirblksize - 1))
866 panic("ext2_add_first_entry: bad directory offset");
868 if (EXT2_HAS_RO_COMPAT_FEATURE(dp->i_e2fs,
869 EXT2F_ROCOMPAT_METADATA_CKSUM)) {
870 entry->e2d_reclen = htole16(dirblksize -
871 sizeof(struct ext2fs_direct_tail));
872 buf = malloc(dirblksize, M_TEMP, M_WAITOK);
873 memcpy(buf, entry, EXT2_DIR_REC_LEN(entry->e2d_namlen));
874 ext2_init_dirent_tail(EXT2_DIRENT_TAIL(buf, dirblksize));
875 ext2_dirent_csum_set(dp, (struct ext2fs_direct_2 *)buf);
877 auio.uio_offset = dp->i_offset;
878 auio.uio_resid = dirblksize;
879 aiov.iov_len = auio.uio_resid;
880 aiov.iov_base = (caddr_t)buf;
882 entry->e2d_reclen = htole16(dirblksize);
883 auio.uio_offset = dp->i_offset;
884 auio.uio_resid = EXT2_DIR_REC_LEN(entry->e2d_namlen);
885 aiov.iov_len = auio.uio_resid;
886 aiov.iov_base = (caddr_t)entry;
889 auio.uio_iov = &aiov;
891 auio.uio_rw = UIO_WRITE;
892 auio.uio_segflg = UIO_SYSSPACE;
893 auio.uio_td = (struct thread *)0;
894 error = VOP_WRITE(dvp, &auio, IO_SYNC, cnp->cn_cred);
898 dp->i_size = roundup2(dp->i_size, dirblksize);
899 dp->i_flag |= IN_CHANGE;
908 * Write a directory entry after a call to namei, using the parameters
909 * that it left in nameidata. The argument ip is the inode which the new
910 * directory entry will refer to. Dvp is a pointer to the directory to
911 * be written, which was left locked by namei. Remaining parameters
912 * (dp->i_offset, dp->i_count) indicate how the space for the new
913 * entry is to be obtained.
916 ext2_direnter(struct inode *ip, struct vnode *dvp, struct componentname *cnp)
919 struct ext2fs_direct_2 newdir;
920 int DIRBLKSIZ = ip->i_e2fs->e2fs_bsize;
924 newdir.e2d_ino = htole32(ip->i_number);
925 if (EXT2_HAS_INCOMPAT_FEATURE(ip->i_e2fs,
926 EXT2F_INCOMPAT_FTYPE)) {
927 newdir.e2d_namlen = cnp->cn_namelen;
928 newdir.e2d_type = DTTOFT(IFTODT(ip->i_mode));
930 newdir.e2d_namlen = htole16(cnp->cn_namelen);
932 bcopy(cnp->cn_nameptr, newdir.e2d_name, (unsigned)cnp->cn_namelen + 1);
934 if (ext2_htree_has_idx(dp)) {
935 error = ext2_htree_add_entry(dvp, &newdir, cnp);
937 dp->i_flag &= ~IN_E3INDEX;
938 dp->i_flag |= IN_CHANGE | IN_UPDATE;
943 if (EXT2_HAS_COMPAT_FEATURE(ip->i_e2fs, EXT2F_COMPAT_DIRHASHINDEX) &&
944 !ext2_htree_has_idx(dp)) {
945 if ((dp->i_size / DIRBLKSIZ) == 1 &&
946 dp->i_offset == DIRBLKSIZ) {
948 * Making indexed directory when one block is not
949 * enough to save all entries.
951 return ext2_htree_create_index(dvp, cnp, &newdir);
956 * If dp->i_count is 0, then namei could find no
957 * space in the directory. Here, dp->i_offset will
958 * be on a directory block boundary and we will write the
959 * new entry into a fresh block.
961 if (dp->i_count == 0)
962 return ext2_add_first_entry(dvp, &newdir, cnp);
964 error = ext2_add_entry(dvp, &newdir);
965 if (!error && dp->i_endoff && dp->i_endoff < dp->i_size)
966 error = ext2_truncate(dvp, (off_t)dp->i_endoff, IO_SYNC,
967 cnp->cn_cred, curthread);
972 * Insert an entry into the directory block.
973 * Compact the contents.
976 ext2_add_entry(struct vnode *dvp, struct ext2fs_direct_2 *entry)
978 struct ext2fs_direct_2 *ep, *nep;
982 int error, loc, newentrysize, spacefree;
988 * If dp->i_count is non-zero, then namei found space
989 * for the new entry in the range dp->i_offset to
990 * dp->i_offset + dp->i_count in the directory.
991 * To use this space, we may have to compact the entries located
992 * there, by copying them together towards the beginning of the
993 * block, leaving the free space in one usable chunk at the end.
997 * Increase size of directory if entry eats into new space.
998 * This should never push the size past a new multiple of
1001 * N.B. - THIS IS AN ARTIFACT OF 4.2 AND SHOULD NEVER HAPPEN.
1003 if (dp->i_offset + dp->i_count > dp->i_size)
1004 dp->i_size = dp->i_offset + dp->i_count;
1006 * Get the block containing the space for the new directory entry.
1008 if ((error = ext2_blkatoff(dvp, (off_t)dp->i_offset, &dirbuf,
1012 * Find space for the new entry. In the simple case, the entry at
1013 * offset base will have the space. If it does not, then namei
1014 * arranged that compacting the region dp->i_offset to
1015 * dp->i_offset + dp->i_count would yield the
1018 newentrysize = EXT2_DIR_REC_LEN(entry->e2d_namlen);
1019 ep = (struct ext2fs_direct_2 *)dirbuf;
1020 dsize = EXT2_DIR_REC_LEN(ep->e2d_namlen);
1021 spacefree = le16toh(ep->e2d_reclen) - dsize;
1022 for (loc = le16toh(ep->e2d_reclen); loc < dp->i_count; ) {
1023 nep = (struct ext2fs_direct_2 *)(dirbuf + loc);
1024 if (le32toh(ep->e2d_ino)) {
1025 /* trim the existing slot */
1026 ep->e2d_reclen = htole16(dsize);
1027 ep = (struct ext2fs_direct_2 *)((char *)ep + dsize);
1029 /* overwrite; nothing there; header is ours */
1032 dsize = EXT2_DIR_REC_LEN(nep->e2d_namlen);
1033 spacefree += le16toh(nep->e2d_reclen) - dsize;
1034 loc += le16toh(nep->e2d_reclen);
1035 bcopy((caddr_t)nep, (caddr_t)ep, dsize);
1038 * Update the pointer fields in the previous entry (if any),
1039 * copy in the new entry, and write out the block.
1041 if (ep->e2d_ino == 0) {
1042 if (spacefree + dsize < newentrysize)
1043 panic("ext2_direnter: compact1");
1044 entry->e2d_reclen = htole16(spacefree + dsize);
1046 if (spacefree < newentrysize)
1047 panic("ext2_direnter: compact2");
1048 entry->e2d_reclen = htole16(spacefree);
1049 ep->e2d_reclen = htole16(dsize);
1050 ep = (struct ext2fs_direct_2 *)((char *)ep + dsize);
1052 bcopy((caddr_t)entry, (caddr_t)ep, (u_int)newentrysize);
1053 ext2_dirent_csum_set(dp, (struct ext2fs_direct_2 *)bp->b_data);
1054 if (DOINGASYNC(dvp)) {
1060 dp->i_flag |= IN_CHANGE | IN_UPDATE;
1065 * Remove a directory entry after a call to namei, using
1066 * the parameters which it left in nameidata. The entry
1067 * dp->i_offset contains the offset into the directory of the
1068 * entry to be eliminated. The dp->i_count field contains the
1069 * size of the previous record in the directory. If this
1070 * is 0, the first entry is being deleted, so we need only
1071 * zero the inode number to mark the entry as free. If the
1072 * entry is not the first in the directory, we must reclaim
1073 * the space of the now empty record by adding the record size
1074 * to the size of the previous entry.
1077 ext2_dirremove(struct vnode *dvp, struct componentname *cnp)
1080 struct ext2fs_direct_2 *ep, *rep;
1085 if (dp->i_count == 0) {
1087 * First entry in block: set d_ino to zero.
1090 ext2_blkatoff(dvp, (off_t)dp->i_offset, (char **)&ep,
1094 ext2_dirent_csum_set(dp, (struct ext2fs_direct_2 *)bp->b_data);
1096 dp->i_flag |= IN_CHANGE | IN_UPDATE;
1100 * Collapse new free space into previous entry.
1102 if ((error = ext2_blkatoff(dvp, (off_t)(dp->i_offset - dp->i_count),
1103 (char **)&ep, &bp)) != 0)
1106 /* Set 'rep' to the entry being removed. */
1107 if (dp->i_count == 0)
1110 rep = (struct ext2fs_direct_2 *)((char *)ep +
1111 le16toh(ep->e2d_reclen));
1112 ep->e2d_reclen += rep->e2d_reclen;
1113 ext2_dirent_csum_set(dp, (struct ext2fs_direct_2 *)bp->b_data);
1114 if (DOINGASYNC(dvp) && dp->i_count != 0)
1118 dp->i_flag |= IN_CHANGE | IN_UPDATE;
1123 * Rewrite an existing directory entry to point at the inode
1124 * supplied. The parameters describing the directory entry are
1125 * set up by a call to namei.
1128 ext2_dirrewrite(struct inode *dp, struct inode *ip, struct componentname *cnp)
1131 struct ext2fs_direct_2 *ep;
1132 struct vnode *vdp = ITOV(dp);
1135 if ((error = ext2_blkatoff(vdp, (off_t)dp->i_offset, (char **)&ep,
1138 ep->e2d_ino = htole32(ip->i_number);
1139 if (EXT2_HAS_INCOMPAT_FEATURE(ip->i_e2fs,
1140 EXT2F_INCOMPAT_FTYPE))
1141 ep->e2d_type = DTTOFT(IFTODT(ip->i_mode));
1143 ep->e2d_type = EXT2_FT_UNKNOWN;
1144 ext2_dirent_csum_set(dp, (struct ext2fs_direct_2 *)bp->b_data);
1146 dp->i_flag |= IN_CHANGE | IN_UPDATE;
1151 * Check if a directory is empty or not.
1152 * Inode supplied must be locked.
1154 * Using a struct dirtemplate here is not precisely
1155 * what we want, but better than using a struct direct.
1157 * NB: does not handle corrupted directories.
1160 ext2_dirempty(struct inode *ip, ino_t parentino, struct ucred *cred)
1163 struct dirtemplate dbuf;
1164 struct ext2fs_direct_2 *dp = (struct ext2fs_direct_2 *)&dbuf;
1167 #define MINDIRSIZ (sizeof(struct dirtemplate) / 2)
1169 for (off = 0; off < ip->i_size; off += le16toh(dp->e2d_reclen)) {
1170 error = vn_rdwr(UIO_READ, ITOV(ip), (caddr_t)dp, MINDIRSIZ,
1171 off, UIO_SYSSPACE, IO_NODELOCKED | IO_NOMACCHECK, cred,
1172 NOCRED, &count, (struct thread *)0);
1174 * Since we read MINDIRSIZ, residual must
1175 * be 0 unless we're at end of file.
1177 if (error || count != 0)
1179 /* avoid infinite loops */
1180 if (dp->e2d_reclen == 0)
1182 /* skip empty entries */
1183 if (dp->e2d_ino == 0)
1185 /* accept only "." and ".." */
1186 namlen = dp->e2d_namlen;
1189 if (dp->e2d_name[0] != '.')
1192 * At this point namlen must be 1 or 2.
1193 * 1 implies ".", 2 implies ".." if second
1198 if (dp->e2d_name[1] == '.' && le32toh(dp->e2d_ino) == parentino)
1206 * Check if source directory is in the path of the target directory.
1207 * Target is supplied locked, source is unlocked.
1208 * The target is always vput before returning.
1211 ext2_checkpath(struct inode *source, struct inode *target, struct ucred *cred)
1215 struct dirtemplate dirbuf;
1218 if (target->i_number == source->i_number) {
1222 if (target->i_number == EXT2_ROOTINO) {
1228 if (vp->v_type != VDIR) {
1232 error = vn_rdwr(UIO_READ, vp, (caddr_t)&dirbuf,
1233 sizeof(struct dirtemplate), (off_t)0, UIO_SYSSPACE,
1234 IO_NODELOCKED | IO_NOMACCHECK, cred, NOCRED, NULL,
1238 namlen = dirbuf.dotdot_type; /* like ufs little-endian */
1240 dirbuf.dotdot_name[0] != '.' ||
1241 dirbuf.dotdot_name[1] != '.') {
1245 if (le32toh(dirbuf.dotdot_ino) == source->i_number) {
1249 if (le32toh(dirbuf.dotdot_ino) == EXT2_ROOTINO)
1252 if ((error = VFS_VGET(vp->v_mount, le32toh(dirbuf.dotdot_ino),
1253 LK_EXCLUSIVE, &vp)) != 0) {
1260 if (error == ENOTDIR)
1261 SDT_PROBE2(ext2fs, , lookup, trace, 1,
1262 "checkpath: .. not a directory");