2 * Copyright (c) 1989, 1993
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34 * @(#)ufs_lookup.c 8.15 (Berkeley) 6/16/95
35 * $FreeBSD: src/sys/ufs/ufs/ufs_lookup.c,v 1.33.2.7 2001/09/22 19:22:13 iedowse Exp $
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/kernel.h>
45 #include <sys/namei.h>
47 #include <sys/mount.h>
48 #include <sys/vnode.h>
49 #include <sys/sysctl.h>
52 #include <vm/vm_extern.h>
61 #include "ufs_extern.h"
62 #include "ffs_extern.h"
70 SYSCTL_INT(_debug, OID_AUTO, dircheck, CTLFLAG_RW, &dirchk, 0,
71 "Enable full validation checks of directory");
73 /* true if old FS format...*/
74 #define OFSFMT(vp) ((vp)->v_mount->mnt_maxsymlinklen <= 0)
77 * Convert a component of a pathname into a pointer to a locked inode.
78 * This is a very central and rather complicated routine.
79 * If the filesystem is not maintained in a strict tree hierarchy,
80 * this can result in a deadlock situation (see comments in code below).
82 * The cnp->cn_nameiop argument is LOOKUP, CREATE, RENAME, or DELETE depending
83 * on whether the name is to be looked up, created, renamed, or deleted.
84 * When CREATE, RENAME, or DELETE is specified, information usable in
85 * creating, renaming, or deleting a directory entry may be calculated.
86 * If flag has LOCKPARENT or'ed into it and the target of the pathname
87 * exists, lookup returns both the target and its parent directory locked.
88 * When creating or renaming and LOCKPARENT is specified, the target may
89 * not be ".". When deleting and LOCKPARENT is specified, the target may
90 * be "."., but the caller must check to ensure it does an vrele and vput
91 * instead of two vputs.
93 * Overall outline of ufs_lookup:
95 * search for name in directory, to found or notfound
97 * if creating, return locked directory, leaving info on available slots
100 * if at end of path and deleting, return information to allow delete
101 * if at end of path and rewriting (RENAME and LOCKPARENT), lock target
102 * inode and return info to allow rewrite
103 * if not at end, add name to cache; if at end and neither creating
104 * nor deleting, add name to cache
106 * ufs_lookup(struct vnode *a_dvp, struct vnode **a_vpp,
107 * struct componentname *a_cnp)
110 ufs_lookup(struct vop_old_lookup_args *ap)
112 struct vnode *vdp; /* vnode for directory being searched */
113 struct inode *dp; /* inode for directory being searched */
114 struct buf *bp; /* a buffer of directory entries */
115 struct direct *ep; /* the current directory entry */
116 int entryoffsetinblock; /* offset of ep in bp's buffer */
117 enum {NONE, COMPACT, FOUND} slotstatus;
118 doff_t slotoffset; /* offset of area with free space */
119 int slotsize; /* size of area at slotoffset */
120 int slotfreespace; /* amount of space free in slot */
121 int slotneeded; /* size of the entry we're seeking */
122 int numdirpasses; /* strategy for directory search */
123 doff_t endsearch; /* offset to end directory search */
124 doff_t prevoff; /* prev entry dp->i_offset */
125 struct vnode *pdp; /* saved dp during symlink work */
126 struct vnode *tdp; /* returned by VFS_VGET */
127 doff_t enduseful; /* pointer past last used dir slot */
128 u_long bmask; /* block offset mask */
129 int lockparent; /* 1 => lockparent flag is set */
130 int wantparent; /* 1 => wantparent or lockparent flag */
132 struct vnode **vpp = ap->a_vpp;
133 struct componentname *cnp = ap->a_cnp;
134 struct ucred *cred = cnp->cn_cred;
135 int flags = cnp->cn_flags;
136 int nameiop = cnp->cn_nameiop;
140 cnp->cn_flags &= ~CNP_PDIRUNLOCK;
142 * XXX there was a soft-update diff about this I couldn't merge.
143 * I think this was the equiv.
149 lockparent = flags & CNP_LOCKPARENT;
150 wantparent = flags & (CNP_LOCKPARENT|CNP_WANTPARENT);
153 * We now have a segment name to search for, and a directory to search.
155 * Suppress search for slots unless creating
156 * file and at end of pathname, in which case
157 * we watch for a place to put the new file in
158 * case it doesn't already exist.
161 slotfreespace = slotsize = slotneeded = 0;
162 if (nameiop == NAMEI_CREATE || nameiop == NAMEI_RENAME) {
164 slotneeded = DIRECTSIZ(cnp->cn_namelen);
166 bmask = VFSTOUFS(vdp->v_mount)->um_mountp->mnt_stat.f_iosize - 1;
170 * Use dirhash for fast operations on large directories. The logic
171 * to determine whether to hash the directory is contained within
172 * ufsdirhash_build(); a zero return means that it decided to hash
173 * this directory and it successfully built up the hash table.
175 if (ufsdirhash_build(dp) == 0) {
176 /* Look for a free slot if needed. */
177 enduseful = dp->i_size;
178 if (slotstatus != FOUND) {
179 slotoffset = ufsdirhash_findfree(dp, slotneeded,
181 if (slotoffset >= 0) {
182 slotstatus = COMPACT;
183 enduseful = ufsdirhash_enduseful(dp);
185 enduseful = dp->i_size;
188 /* Look up the component. */
190 entryoffsetinblock = 0; /* silence compiler warning */
191 switch (ufsdirhash_lookup(dp, cnp->cn_nameptr, cnp->cn_namelen,
192 &dp->i_offset, &bp, nameiop == NAMEI_DELETE ? &prevoff : NULL)) {
194 ep = (struct direct *)((char *)bp->b_data +
195 (dp->i_offset & bmask));
198 dp->i_offset = roundup2(dp->i_size, DIRBLKSIZ);
201 /* Something failed; just do a linear search. */
205 #endif /* UFS_DIRHASH */
207 * If there is cached information on a previous search of
208 * this directory, pick up where we last left off.
209 * We cache only lookups as these are the most common
210 * and have the greatest payoff. Caching CREATE has little
211 * benefit as it usually must search the entire directory
212 * to determine that the entry does not exist. Caching the
213 * location of the last DELETE or RENAME has not reduced
214 * profiling time and hence has been removed in the interest
217 if (nameiop != NAMEI_LOOKUP || dp->i_diroff == 0 ||
218 dp->i_diroff >= dp->i_size) {
219 entryoffsetinblock = 0;
223 dp->i_offset = dp->i_diroff;
224 if ((entryoffsetinblock = dp->i_offset & bmask) &&
225 (error = ffs_blkatoff(vdp, (off_t)dp->i_offset, NULL, &bp)))
229 prevoff = dp->i_offset;
230 endsearch = roundup2(dp->i_size, DIRBLKSIZ);
234 while (dp->i_offset < endsearch) {
236 * If necessary, get the next directory block.
238 if ((dp->i_offset & bmask) == 0) {
242 ffs_blkatoff(vdp, (off_t)dp->i_offset, NULL, &bp);
245 entryoffsetinblock = 0;
248 * If still looking for a slot, and at a DIRBLKSIZE
249 * boundary, have to start looking for free space again.
251 if (slotstatus == NONE &&
252 (entryoffsetinblock & (DIRBLKSIZ - 1)) == 0) {
257 * Get pointer to next entry.
258 * Full validation checks are slow, so we only check
259 * enough to insure forward progress through the
260 * directory. Complete checks can be run by patching
261 * "dirchk" to be true.
263 ep = (struct direct *)((char *)bp->b_data + entryoffsetinblock);
264 if (ep->d_reclen == 0 || ep->d_reclen >
265 DIRBLKSIZ - (entryoffsetinblock & (DIRBLKSIZ - 1)) ||
266 (dirchk && ufs_dirbadentry(vdp, ep, entryoffsetinblock))) {
269 ufs_dirbad(dp, dp->i_offset, "mangled entry");
270 i = DIRBLKSIZ - (entryoffsetinblock & (DIRBLKSIZ - 1));
272 entryoffsetinblock += i;
277 * If an appropriate sized slot has not yet been found,
278 * check to see if one is available. Also accumulate space
279 * in the current block so that we can determine if
280 * compaction is viable.
282 if (slotstatus != FOUND) {
283 int size = ep->d_reclen;
286 size -= DIRSIZ(OFSFMT(vdp), ep);
288 if (size >= slotneeded) {
290 slotoffset = dp->i_offset;
291 slotsize = ep->d_reclen;
292 } else if (slotstatus == NONE) {
293 slotfreespace += size;
294 if (slotoffset == -1)
295 slotoffset = dp->i_offset;
296 if (slotfreespace >= slotneeded) {
297 slotstatus = COMPACT;
298 slotsize = dp->i_offset +
299 ep->d_reclen - slotoffset;
306 * Check for a name match.
309 # if (BYTE_ORDER == LITTLE_ENDIAN)
313 namlen = ep->d_namlen;
315 namlen = ep->d_namlen;
317 if (namlen == cnp->cn_namelen &&
318 (cnp->cn_nameptr[0] == ep->d_name[0]) &&
319 !bcmp(cnp->cn_nameptr, ep->d_name,
325 * Save directory entry's inode number and
326 * reclen in ndp->ni_ufs area, and release
329 if (vdp->v_mount->mnt_maxsymlinklen > 0 &&
330 ep->d_type == DT_WHT) {
332 slotoffset = dp->i_offset;
333 slotsize = ep->d_reclen;
334 dp->i_reclen = slotsize;
335 enduseful = dp->i_size;
336 ap->a_cnp->cn_flags |= CNP_ISWHITEOUT;
340 dp->i_ino = ep->d_ino;
341 dp->i_reclen = ep->d_reclen;
345 prevoff = dp->i_offset;
346 dp->i_offset += ep->d_reclen;
347 entryoffsetinblock += ep->d_reclen;
349 enduseful = dp->i_offset;
353 * If we started in the middle of the directory and failed
354 * to find our target, we must check the beginning as well.
356 if (numdirpasses == 2) {
359 endsearch = dp->i_diroff;
365 * If creating, and at end of pathname and current
366 * directory has not been removed, then can consider
367 * allowing file to be created.
369 if ((nameiop == NAMEI_CREATE || nameiop == NAMEI_RENAME ||
370 (nameiop == NAMEI_DELETE &&
371 (ap->a_cnp->cn_flags & CNP_DOWHITEOUT) &&
372 (ap->a_cnp->cn_flags & CNP_ISWHITEOUT))) &&
373 dp->i_effnlink != 0) {
375 * Access for write is interpreted as allowing
376 * creation of files in the directory.
378 error = VOP_EACCESS(vdp, VWRITE, cred);
382 * Return an indication of where the new directory
383 * entry should be put. If we didn't find a slot,
384 * then set dp->i_count to 0 indicating
385 * that the new slot belongs at the end of the
386 * directory. If we found a slot, then the new entry
387 * can be put in the range from dp->i_offset to
388 * dp->i_offset + dp->i_count.
390 if (slotstatus == NONE) {
391 dp->i_offset = roundup2(dp->i_size, DIRBLKSIZ);
393 enduseful = dp->i_offset;
394 } else if (nameiop == NAMEI_DELETE) {
395 dp->i_offset = slotoffset;
396 if ((dp->i_offset & (DIRBLKSIZ - 1)) == 0)
399 dp->i_count = dp->i_offset - prevoff;
401 dp->i_offset = slotoffset;
402 dp->i_count = slotsize;
403 if (enduseful < slotoffset + slotsize)
404 enduseful = slotoffset + slotsize;
406 dp->i_endoff = roundup2(enduseful, DIRBLKSIZ);
407 dp->i_flag |= IN_CHANGE | IN_UPDATE;
409 * We return with the directory locked, so that
410 * the parameters we set up above will still be
411 * valid if we actually decide to do a direnter().
412 * We return ni_vp == NULL to indicate that the entry
413 * does not currently exist; we leave a pointer to
414 * the (locked) directory inode in ndp->ni_dvp.
415 * The pathname buffer is saved so that the name
416 * can be obtained later.
418 * NB - if the directory is unlocked, then this
419 * information cannot be used.
423 cnp->cn_flags |= CNP_PDIRUNLOCK;
425 return (EJUSTRETURN);
431 * Check that directory length properly reflects presence
434 if (dp->i_offset + DIRSIZ(OFSFMT(vdp), ep) > dp->i_size) {
435 ufs_dirbad(dp, dp->i_offset, "i_size too small");
436 dp->i_size = dp->i_offset + DIRSIZ(OFSFMT(vdp), ep);
437 dp->i_flag |= IN_CHANGE | IN_UPDATE;
442 * Found component in pathname.
443 * If the final component of path name, save information
444 * in the cache as to where the entry was found.
446 if (nameiop == NAMEI_LOOKUP)
447 dp->i_diroff = dp->i_offset &~ (DIRBLKSIZ - 1);
450 * If deleting, and at end of pathname, return
451 * parameters which can be used to remove file.
452 * If the wantparent flag isn't set, we return only
453 * the directory (in ndp->ni_dvp), otherwise we go
454 * on and lock the inode, being careful with ".".
456 if (nameiop == NAMEI_DELETE) {
458 * Write access to directory required to delete files.
460 error = VOP_EACCESS(vdp, VWRITE, cred);
464 * Return pointer to current entry in dp->i_offset,
465 * and distance past previous entry (if there
466 * is a previous entry in this block) in dp->i_count.
467 * Save directory inode pointer in ndp->ni_dvp for dirremove().
469 if ((dp->i_offset & (DIRBLKSIZ - 1)) == 0)
472 dp->i_count = dp->i_offset - prevoff;
473 if (dp->i_number == dp->i_ino) {
478 if (flags & CNP_ISDOTDOT)
479 vn_unlock(vdp); /* race to get the inode */
480 error = VFS_VGET(vdp->v_mount, NULL, dp->i_ino, &tdp);
481 if (flags & CNP_ISDOTDOT) {
482 if (vn_lock(vdp, LK_EXCLUSIVE | LK_RETRY |
483 LK_FAILRECLAIM) != 0) {
484 cnp->cn_flags |= CNP_PDIRUNLOCK;
490 * If directory is "sticky", then user must own
491 * the directory, or the file in it, else she
492 * may not delete it (unless she's root). This
493 * implements append-only directories.
495 if ((dp->i_mode & ISVTX) &&
497 cred->cr_uid != dp->i_uid &&
498 VTOI(tdp)->i_uid != cred->cr_uid) {
505 cnp->cn_flags |= CNP_PDIRUNLOCK;
511 * If rewriting (RENAME), return the inode and the
512 * information required to rewrite the present directory
513 * Must get inode of directory entry to verify it's a
514 * regular file, or empty directory.
516 if (nameiop == NAMEI_RENAME && wantparent) {
517 if ((error = VOP_EACCESS(vdp, VWRITE, cred)) != 0)
520 * Careful about locking second inode.
521 * This can only occur if the target is ".".
523 if (dp->i_number == dp->i_ino)
525 if (flags & CNP_ISDOTDOT)
526 vn_unlock(vdp); /* race to get the inode */
527 error = VFS_VGET(vdp->v_mount, NULL, dp->i_ino, &tdp);
528 if (flags & CNP_ISDOTDOT) {
529 if (vn_lock(vdp, LK_EXCLUSIVE | LK_RETRY |
530 LK_FAILRECLAIM) != 0) {
531 cnp->cn_flags |= CNP_PDIRUNLOCK;
539 cnp->cn_flags |= CNP_PDIRUNLOCK;
545 * Step through the translation in the name. We do not `vput' the
546 * directory because we may need it again if a symbolic link
547 * is relative to the current directory. Instead we save it
548 * unlocked as "pdp". We must get the target inode before unlocking
549 * the directory to insure that the inode will not be removed
550 * before we get it. We prevent deadlock by always fetching
551 * inodes from the root, moving down the directory tree. Thus
552 * when following backward pointers ".." we must unlock the
553 * parent directory before getting the requested directory.
554 * There is a potential race condition here if both the current
555 * and parent directories are removed before the VFS_VGET for the
556 * inode associated with ".." returns. We hope that this occurs
557 * infrequently since we cannot avoid this race condition without
558 * implementing a sophisticated deadlock detection algorithm.
559 * Note also that this simple deadlock detection scheme will not
560 * work if the filesystem has any hard links other than ".."
561 * that point backwards in the directory structure.
564 if (flags & CNP_ISDOTDOT) {
565 vn_unlock(pdp); /* race to get the inode */
566 cnp->cn_flags |= CNP_PDIRUNLOCK;
567 error = VFS_VGET(vdp->v_mount, NULL, dp->i_ino, &tdp);
569 if (vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY |
570 LK_FAILRECLAIM) == 0) {
571 cnp->cn_flags &= ~CNP_PDIRUNLOCK;
576 error = vn_lock(pdp, LK_EXCLUSIVE | LK_FAILRECLAIM);
581 cnp->cn_flags &= ~CNP_PDIRUNLOCK;
584 } else if (dp->i_number == dp->i_ino) {
585 vref(vdp); /* we want ourself, ie "." */
588 error = VFS_VGET(vdp->v_mount, NULL, dp->i_ino, &tdp);
593 cnp->cn_flags |= CNP_PDIRUNLOCK;
601 ufs_dirbad(struct inode *ip, doff_t offset, char *how)
605 mp = ITOV(ip)->v_mount;
606 (void)kprintf("%s: bad dir ino %lu at offset %ld: %s\n",
607 mp->mnt_stat.f_mntfromname, (u_long)ip->i_number, (long)offset, how);
608 if ((mp->mnt_flag & MNT_RDONLY) == 0)
609 panic("ufs_dirbad: bad dir");
613 * Do consistency checking on a directory entry:
614 * record length must be multiple of 4
615 * entry must fit in rest of its DIRBLKSIZ block
616 * record must be large enough to contain entry
617 * name is not longer than MAXNAMLEN
618 * name must be as long as advertised, and null terminated
621 ufs_dirbadentry(struct vnode *dp, struct direct *ep, int entryoffsetinblock)
626 # if (BYTE_ORDER == LITTLE_ENDIAN)
630 namlen = ep->d_namlen;
632 namlen = ep->d_namlen;
634 if ((ep->d_reclen & 0x3) != 0 ||
635 ep->d_reclen > DIRBLKSIZ - (entryoffsetinblock & (DIRBLKSIZ - 1)) ||
636 ep->d_reclen < DIRSIZ(OFSFMT(dp), ep) || namlen > MAXNAMLEN) {
638 kprintf("First bad\n");
643 for (i = 0; i < namlen; i++)
644 if (ep->d_name[i] == '\0') {
646 kprintf("Second bad\n");
657 * Construct a new directory entry after a call to namei, using the
658 * parameters that it left in the componentname argument cnp. The
659 * argument ip is the inode to which the new directory entry will refer.
662 ufs_makedirentry(struct inode *ip, struct componentname *cnp,
663 struct direct *newdirp)
666 newdirp->d_ino = ip->i_number;
667 newdirp->d_namlen = cnp->cn_namelen;
668 bcopy(cnp->cn_nameptr, newdirp->d_name, (unsigned)cnp->cn_namelen + 1);
669 if (ITOV(ip)->v_mount->mnt_maxsymlinklen > 0)
670 newdirp->d_type = IFTODT(ip->i_mode);
673 # if (BYTE_ORDER == LITTLE_ENDIAN)
674 { u_char tmp = newdirp->d_namlen;
675 newdirp->d_namlen = newdirp->d_type;
676 newdirp->d_type = tmp; }
682 * Write a directory entry after a call to namei, using the parameters
683 * that it left in the directory inode. The argument dirp is the new directory
684 * entry contents. Dvp is a pointer to the directory to be written,
685 * which was left locked by namei. Remaining parameters (dp->i_offset,
686 * dp->i_count) indicate how the space for the new entry is to be obtained.
687 * Non-null bp indicates that a directory is being created (for the
688 * soft dependency code).
691 ufs_direnter(struct vnode *dvp, struct vnode *tvp, struct direct *dirp,
692 struct componentname *cnp, struct buf *newdirbp)
699 struct direct *ep, *nep;
700 int error, ret, blkoff, loc, spacefree, flags;
704 KKASSERT(cred != NULL);
707 newentrysize = DIRSIZ(OFSFMT(dvp), dirp);
709 if (dp->i_count == 0) {
711 * If dp->i_count is 0, then namei could find no
712 * space in the directory. Here, dp->i_offset will
713 * be on a directory block boundary and we will write the
714 * new entry into a fresh block.
716 if (dp->i_offset & (DIRBLKSIZ - 1))
717 panic("ufs_direnter: newblk");
718 nvnode_pager_setsize(dvp, dp->i_offset + DIRBLKSIZ,
721 if (!DOINGSOFTDEP(dvp) && !DOINGASYNC(dvp))
723 if ((error = VOP_BALLOC(dvp, (off_t)dp->i_offset, DIRBLKSIZ,
724 cred, flags, &bp)) != 0) {
725 if (DOINGSOFTDEP(dvp) && newdirbp != NULL)
729 dp->i_size = dp->i_offset + DIRBLKSIZ;
730 dp->i_flag |= IN_CHANGE | IN_UPDATE;
731 dirp->d_reclen = DIRBLKSIZ;
732 blkoff = dp->i_offset &
733 (VFSTOUFS(dvp->v_mount)->um_mountp->mnt_stat.f_iosize - 1);
734 bcopy((caddr_t)dirp, (caddr_t)bp->b_data + blkoff,newentrysize);
736 if (dp->i_dirhash != NULL) {
737 ufsdirhash_newblk(dp, dp->i_offset);
738 ufsdirhash_add(dp, dirp, dp->i_offset);
739 ufsdirhash_checkblock(dp, (char *)bp->b_data + blkoff,
743 if (DOINGSOFTDEP(dvp)) {
745 * Ensure that the entire newly allocated block is a
746 * valid directory so that future growth within the
747 * block does not have to ensure that the block is
748 * written before the inode.
751 while (blkoff < bp->b_bcount) {
753 (bp->b_data + blkoff))->d_reclen = DIRBLKSIZ;
756 softdep_setup_directory_add(bp, dp, dp->i_offset,
757 dirp->d_ino, newdirbp);
759 return (ffs_update(dvp, 0));
761 if (DOINGASYNC(dvp)) {
763 return (ffs_update(dvp, 0));
766 ret = ffs_update(dvp, 1);
773 * If dp->i_count is non-zero, then namei found space for the new
774 * entry in the range dp->i_offset to dp->i_offset + dp->i_count
775 * in the directory. To use this space, we may have to compact
776 * the entries located there, by copying them together towards the
777 * beginning of the block, leaving the free space in one usable
782 * Increase size of directory if entry eats into new space.
783 * This should never push the size past a new multiple of
786 * N.B. - THIS IS AN ARTIFACT OF 4.2 AND SHOULD NEVER HAPPEN.
788 if (dp->i_offset + dp->i_count > dp->i_size)
789 dp->i_size = dp->i_offset + dp->i_count;
791 * Get the block containing the space for the new directory entry.
793 error = ffs_blkatoff(dvp, (off_t)dp->i_offset, &dirbuf, &bp);
795 if (DOINGSOFTDEP(dvp) && newdirbp != NULL)
800 * Find space for the new entry. In the simple case, the entry at
801 * offset base will have the space. If it does not, then namei
802 * arranged that compacting the region dp->i_offset to
803 * dp->i_offset + dp->i_count would yield the space.
805 ep = (struct direct *)dirbuf;
806 dsize = ep->d_ino ? DIRSIZ(OFSFMT(dvp), ep) : 0;
807 spacefree = ep->d_reclen - dsize;
808 for (loc = ep->d_reclen; loc < dp->i_count; ) {
809 nep = (struct direct *)(dirbuf + loc);
811 /* Trim the existing slot (NB: dsize may be zero). */
812 ep->d_reclen = dsize;
813 ep = (struct direct *)((char *)ep + dsize);
815 /* Read nep->d_reclen now as the bcopy() may clobber it. */
816 loc += nep->d_reclen;
817 if (nep->d_ino == 0) {
819 * A mid-block unused entry. Such entries are
820 * never created by the kernel, but fsck_ffs
821 * can create them (and it doesn't fix them).
823 * Add up the free space, and initialise the
824 * relocated entry since we don't bcopy it.
826 spacefree += nep->d_reclen;
831 dsize = DIRSIZ(OFSFMT(dvp), nep);
832 spacefree += nep->d_reclen - dsize;
834 if (dp->i_dirhash != NULL)
835 ufsdirhash_move(dp, nep,
836 dp->i_offset + ((char *)nep - dirbuf),
837 dp->i_offset + ((char *)ep - dirbuf));
839 if (DOINGSOFTDEP(dvp))
840 softdep_change_directoryentry_offset(dp, dirbuf,
841 (caddr_t)nep, (caddr_t)ep, dsize);
843 bcopy((caddr_t)nep, (caddr_t)ep, dsize);
846 * Here, `ep' points to a directory entry containing `dsize' in-use
847 * bytes followed by `spacefree' unused bytes. If ep->d_ino == 0,
848 * then the entry is completely unused (dsize == 0). The value
849 * of ep->d_reclen is always indeterminate.
851 * Update the pointer fields in the previous entry (if any),
852 * copy in the new entry, and write out the block.
854 if (ep->d_ino == 0 ||
855 (ep->d_ino == UFS_WINO &&
856 bcmp(ep->d_name, dirp->d_name, dirp->d_namlen) == 0)) {
857 if (spacefree + dsize < newentrysize)
858 panic("ufs_direnter: compact1");
859 dirp->d_reclen = spacefree + dsize;
861 if (spacefree < newentrysize)
862 panic("ufs_direnter: compact2");
863 dirp->d_reclen = spacefree;
864 ep->d_reclen = dsize;
865 ep = (struct direct *)((char *)ep + dsize);
868 if (dp->i_dirhash != NULL && (ep->d_ino == 0 ||
869 dirp->d_reclen == spacefree))
870 ufsdirhash_add(dp, dirp, dp->i_offset + ((char *)ep - dirbuf));
872 bcopy((caddr_t)dirp, (caddr_t)ep, (uint)newentrysize);
874 if (dp->i_dirhash != NULL)
875 ufsdirhash_checkblock(dp, dirbuf -
876 (dp->i_offset & (DIRBLKSIZ - 1)),
877 dp->i_offset & ~(DIRBLKSIZ - 1));
880 if (DOINGSOFTDEP(dvp)) {
881 softdep_setup_directory_add(bp, dp,
882 dp->i_offset + (caddr_t)ep - dirbuf, dirp->d_ino, newdirbp);
885 if (DOINGASYNC(dvp)) {
892 dp->i_flag |= IN_CHANGE | IN_UPDATE;
894 * If all went well, and the directory can be shortened, proceed
895 * with the truncation. Note that we have to unlock the inode for
896 * the entry that we just entered, as the truncation may need to
897 * lock other inodes which can lead to deadlock if we also hold a
898 * lock on the newly entered node.
900 if (error == 0 && dp->i_endoff && dp->i_endoff < dp->i_size) {
904 if (dp->i_dirhash != NULL)
905 ufsdirhash_dirtrunc(dp, dp->i_endoff);
907 (void)ffs_truncate(dvp, (off_t)dp->i_endoff, IO_SYNC, cred);
909 vn_lock(tvp, LK_EXCLUSIVE | LK_RETRY);
915 * Remove a directory entry after a call to namei, using
916 * the parameters which it left in the directory inode. The entry
917 * dp->i_offset contains the offset into the directory of the
918 * entry to be eliminated. The dp->i_count field contains the
919 * size of the previous record in the directory. If this
920 * is 0, the first entry is being deleted, so we need only
921 * zero the inode number to mark the entry as free. If the
922 * entry is not the first in the directory, we must reclaim
923 * the space of the now empty record by adding the record size
924 * to the size of the previous entry.
927 ufs_dirremove(struct vnode *dvp, struct inode *ip, int flags, int isrmdir)
936 if (flags & CNP_DOWHITEOUT) {
938 * Whiteout entry: set d_ino to UFS_WINO.
941 ffs_blkatoff(dvp, (off_t)dp->i_offset, (char **)&ep, &bp)) != 0)
943 ep->d_ino = UFS_WINO;
948 if ((error = ffs_blkatoff(dvp,
949 (off_t)(dp->i_offset - dp->i_count), (char **)&ep, &bp)) != 0)
953 * Remove the dirhash entry. This is complicated by the fact
954 * that `ep' is the previous entry when dp->i_count != 0.
956 if (dp->i_dirhash != NULL)
957 ufsdirhash_remove(dp, (dp->i_count == 0) ? ep :
958 (struct direct *)((char *)ep + ep->d_reclen), dp->i_offset);
960 if (dp->i_count == 0) {
962 * First entry in block: set d_ino to zero.
967 * Collapse new free space into previous entry.
969 ep->d_reclen += dp->i_reclen;
972 if (dp->i_dirhash != NULL)
973 ufsdirhash_checkblock(dp, (char *)ep -
974 ((dp->i_offset - dp->i_count) & (DIRBLKSIZ - 1)),
975 dp->i_offset & ~(DIRBLKSIZ - 1));
978 if (DOINGSOFTDEP(dvp)) {
981 softdep_change_linkcnt(ip);
982 softdep_setup_remove(bp, dp, ip, isrmdir);
984 if (softdep_slowdown(dvp)) {
994 ip->i_flag |= IN_CHANGE;
996 if (flags & CNP_DOWHITEOUT)
998 else if (DOINGASYNC(dvp) && dp->i_count != 0) {
1005 dp->i_flag |= IN_CHANGE | IN_UPDATE;
1010 * Rewrite an existing directory entry to point at the inode
1011 * supplied. The parameters describing the directory entry are
1012 * set up by a call to namei.
1015 ufs_dirrewrite(struct inode *dp, struct inode *oip, ino_t newinum, int newtype,
1020 struct vnode *vdp = ITOV(dp);
1023 error = ffs_blkatoff(vdp, (off_t)dp->i_offset, (char **)&ep, &bp);
1026 ep->d_ino = newinum;
1028 ep->d_type = newtype;
1030 if (DOINGSOFTDEP(vdp)) {
1031 softdep_change_linkcnt(oip);
1032 softdep_setup_directory_change(bp, dp, oip, newinum, isrmdir);
1036 oip->i_flag |= IN_CHANGE;
1037 if (DOINGASYNC(vdp)) {
1044 dp->i_flag |= IN_CHANGE | IN_UPDATE;
1049 * Check if a directory is empty or not.
1050 * Inode supplied must be locked.
1052 * Using a struct dirtemplate here is not precisely
1053 * what we want, but better than using a struct direct.
1055 * NB: does not handle corrupted directories.
1058 ufs_dirempty(struct inode *ip, ino_t parentino, struct ucred *cred)
1061 struct dirtemplate dbuf;
1062 struct direct *dp = (struct direct *)&dbuf;
1063 int error, count, namlen;
1064 #define MINDIRSIZ (sizeof (struct dirtemplate) / 2)
1066 for (off = 0; off < ip->i_size; off += dp->d_reclen) {
1067 error = vn_rdwr(UIO_READ, ITOV(ip), (caddr_t)dp, MINDIRSIZ, off,
1068 UIO_SYSSPACE, IO_NODELOCKED, cred, &count);
1070 * Since we read MINDIRSIZ, residual must
1071 * be 0 unless we're at end of file.
1073 if (error || count != 0)
1075 /* avoid infinite loops */
1076 if (dp->d_reclen == 0)
1078 /* skip empty entries */
1079 if (dp->d_ino == 0 || dp->d_ino == UFS_WINO)
1081 /* accept only "." and ".." */
1082 # if (BYTE_ORDER == LITTLE_ENDIAN)
1083 if (OFSFMT(ITOV(ip)))
1084 namlen = dp->d_type;
1086 namlen = dp->d_namlen;
1088 namlen = dp->d_namlen;
1092 if (dp->d_name[0] != '.')
1095 * At this point namlen must be 1 or 2.
1096 * 1 implies ".", 2 implies ".." if second
1099 if (namlen == 1 && dp->d_ino == ip->i_number)
1101 if (dp->d_name[1] == '.' && dp->d_ino == parentino)
1109 * Check if source directory is in the path of the target directory.
1110 * Target is supplied locked, source is unlocked.
1111 * The target is always vput before returning.
1114 ufs_checkpath(struct inode *source, struct inode *target, struct ucred *cred)
1117 int error, rootino, namlen;
1118 struct dirtemplate dirbuf;
1121 if (target->i_number == source->i_number) {
1125 rootino = UFS_ROOTINO;
1127 if (target->i_number == rootino)
1131 if (vp->v_type != VDIR) {
1135 error = vn_rdwr(UIO_READ, vp, (caddr_t)&dirbuf,
1136 sizeof (struct dirtemplate), (off_t)0,
1137 UIO_SYSSPACE, IO_NODELOCKED, cred, NULL);
1140 # if (BYTE_ORDER == LITTLE_ENDIAN)
1142 namlen = dirbuf.dotdot_type;
1144 namlen = dirbuf.dotdot_namlen;
1146 namlen = dirbuf.dotdot_namlen;
1149 dirbuf.dotdot_name[0] != '.' ||
1150 dirbuf.dotdot_name[1] != '.') {
1154 if (dirbuf.dotdot_ino == source->i_number) {
1158 if (dirbuf.dotdot_ino == rootino)
1161 error = VFS_VGET(vp->v_mount, NULL, dirbuf.dotdot_ino, &vp);
1169 if (error == ENOTDIR)
1170 kprintf("checkpath: .. not a directory\n");