4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
26 #pragma ident "@(#)zfs_dir.c 1.25 08/04/27 SMI"
28 #include <sys/types.h>
29 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/sysmacros.h>
33 #include <sys/resource.h>
35 #include <sys/vnode.h>
40 #include <sys/pathname.h>
41 #include <sys/cmn_err.h>
42 #include <sys/errno.h>
44 #include <sys/unistd.h>
45 #include <sys/sunddi.h>
46 #include <sys/random.h>
47 #include <sys/policy.h>
48 #include <sys/zfs_dir.h>
49 #include <sys/zfs_acl.h>
50 #include <sys/fs/zfs.h>
51 #include "fs/fs_subr.h"
54 #include <sys/atomic.h>
55 #include <sys/zfs_ctldir.h>
56 #include <sys/zfs_fuid.h>
58 #include <sys/extdirent.h>
61 * zfs_match_find() is used by zfs_dirent_lock() to peform zap lookups
62 * of names after deciding which is the appropriate lookup interface.
65 zfs_match_find(zfsvfs_t *zfsvfs, znode_t *dzp, char *name, boolean_t exact,
66 boolean_t update, int *deflags, pathname_t *rpnp, uint64_t *zoid)
71 matchtype_t mt = MT_FIRST;
72 boolean_t conflict = B_FALSE;
78 bufsz = rpnp->pn_bufsize;
83 * In the non-mixed case we only expect there would ever
84 * be one match, but we need to use the normalizing lookup.
86 error = zap_lookup_norm(zfsvfs->z_os, dzp->z_id, name, 8, 1,
87 zoid, mt, buf, bufsz, &conflict);
88 if (!error && deflags)
89 *deflags = conflict ? ED_CASE_CONFLICT : 0;
91 error = zap_lookup(zfsvfs->z_os, dzp->z_id, name, 8, 1, zoid);
93 *zoid = ZFS_DIRENT_OBJ(*zoid);
95 if (error == ENOENT && update)
96 dnlc_update(ZTOV(dzp), name, DNLC_NO_VNODE);
102 * Lock a directory entry. A dirlock on <dzp, name> protects that name
103 * in dzp's directory zap object. As long as you hold a dirlock, you can
104 * assume two things: (1) dzp cannot be reaped, and (2) no other thread
105 * can change the zap entry for (i.e. link or unlink) this name.
108 * dzp - znode for directory
109 * name - name of entry to lock
110 * flag - ZNEW: if the entry already exists, fail with EEXIST.
111 * ZEXISTS: if the entry does not exist, fail with ENOENT.
112 * ZSHARED: allow concurrent access with other ZSHARED callers.
113 * ZXATTR: we want dzp's xattr directory
114 * ZCILOOK: On a mixed sensitivity file system,
115 * this lookup should be case-insensitive.
116 * ZCIEXACT: On a purely case-insensitive file system,
117 * this lookup should be case-sensitive.
118 * ZRENAMING: we are locking for renaming, force narrow locks
121 * zpp - pointer to the znode for the entry (NULL if there isn't one)
122 * dlpp - pointer to the dirlock for this entry (NULL on error)
123 * direntflags - (case-insensitive lookup only)
124 * flags if multiple case-sensitive matches exist in directory
125 * realpnp - (case-insensitive lookup only)
126 * actual name matched within the directory
128 * Return value: 0 on success or errno on failure.
130 * NOTE: Always checks for, and rejects, '.' and '..'.
131 * NOTE: For case-insensitive file systems we take wide locks (see below),
132 * but return znode pointers to a single match.
135 zfs_dirent_lock(zfs_dirlock_t **dlpp, znode_t *dzp, char *name, znode_t **zpp,
136 int flag, int *direntflags, pathname_t *realpnp)
138 zfsvfs_t *zfsvfs = dzp->z_zfsvfs;
151 * Verify that we are not trying to lock '.', '..', or '.zfs'
153 if (name[0] == '.' &&
154 (name[1] == '\0' || (name[1] == '.' && name[2] == '\0')) ||
155 zfs_has_ctldir(dzp) && strcmp(name, ZFS_CTLDIR_NAME) == 0)
159 * Case sensitivity and normalization preferences are set when
160 * the file system is created. These are stored in the
161 * zfsvfs->z_case and zfsvfs->z_norm fields. These choices
162 * affect what vnodes can be cached in the DNLC, how we
163 * perform zap lookups, and the "width" of our dirlocks.
165 * A normal dirlock locks a single name. Note that with
166 * normalization a name can be composed multiple ways, but
167 * when normalized, these names all compare equal. A wide
168 * dirlock locks multiple names. We need these when the file
169 * system is supporting mixed-mode access. It is sometimes
170 * necessary to lock all case permutations of file name at
171 * once so that simultaneous case-insensitive/case-sensitive
172 * behaves as rationally as possible.
176 * Decide if exact matches should be requested when performing
177 * a zap lookup on file systems supporting case-insensitive
181 ((zfsvfs->z_case == ZFS_CASE_INSENSITIVE) && (flag & ZCIEXACT)) ||
182 ((zfsvfs->z_case == ZFS_CASE_MIXED) && !(flag & ZCILOOK));
185 * Only look in or update the DNLC if we are looking for the
186 * name on a file system that does not require normalization
187 * or case folding. We can also look there if we happen to be
188 * on a non-normalizing, mixed sensitivity file system IF we
189 * are looking for the exact name.
191 * Maybe can add TO-UPPERed version of name to dnlc in ci-only
192 * case for performance improvement?
194 update = !zfsvfs->z_norm ||
195 ((zfsvfs->z_case == ZFS_CASE_MIXED) &&
196 !(zfsvfs->z_norm & ~U8_TEXTPREP_TOUPPER) && !(flag & ZCILOOK));
199 * ZRENAMING indicates we are in a situation where we should
200 * take narrow locks regardless of the file system's
201 * preferences for normalizing and case folding. This will
202 * prevent us deadlocking trying to grab the same wide lock
203 * twice if the two names happen to be case-insensitive
206 if (flag & ZRENAMING)
209 cmpflags = zfsvfs->z_norm;
212 * Wait until there are no locks on this name.
214 rw_enter(&dzp->z_name_lock, RW_READER);
215 mutex_enter(&dzp->z_lock);
217 if (dzp->z_unlinked) {
218 mutex_exit(&dzp->z_lock);
219 rw_exit(&dzp->z_name_lock);
222 for (dl = dzp->z_dirlocks; dl != NULL; dl = dl->dl_next) {
223 if ((u8_strcmp(name, dl->dl_name, 0, cmpflags,
224 U8_UNICODE_LATEST, &error) == 0) || error != 0)
228 mutex_exit(&dzp->z_lock);
229 rw_exit(&dzp->z_name_lock);
234 * Allocate a new dirlock and add it to the list.
236 dl = kmem_alloc(sizeof (zfs_dirlock_t), KM_SLEEP);
237 cv_init(&dl->dl_cv, NULL, CV_DEFAULT, NULL);
242 dl->dl_next = dzp->z_dirlocks;
243 dzp->z_dirlocks = dl;
246 if ((flag & ZSHARED) && dl->dl_sharecnt != 0)
248 cv_wait(&dl->dl_cv, &dzp->z_lock);
251 if ((flag & ZSHARED) && ++dl->dl_sharecnt > 1 && dl->dl_namesize == 0) {
253 * We're the second shared reference to dl. Make a copy of
254 * dl_name in case the first thread goes away before we do.
255 * Note that we initialize the new name before storing its
256 * pointer into dl_name, because the first thread may load
257 * dl->dl_name at any time. He'll either see the old value,
258 * which is his, or the new shared copy; either is OK.
260 dl->dl_namesize = strlen(dl->dl_name) + 1;
261 name = kmem_alloc(dl->dl_namesize, KM_SLEEP);
262 bcopy(dl->dl_name, name, dl->dl_namesize);
266 mutex_exit(&dzp->z_lock);
269 * We have a dirlock on the name. (Note that it is the dirlock,
270 * not the dzp's z_lock, that protects the name in the zap object.)
271 * See if there's an object by this name; if so, put a hold on it.
274 zoid = dzp->z_phys->zp_xattr;
275 error = (zoid == 0 ? ENOENT : 0);
278 vp = dnlc_lookup(ZTOV(dzp), name);
279 if (vp == DNLC_NO_VNODE) {
284 zfs_dirent_unlock(dl);
292 error = zfs_match_find(zfsvfs, dzp, name, exact,
293 update, direntflags, realpnp, &zoid);
297 if (error != ENOENT || (flag & ZEXISTS)) {
298 zfs_dirent_unlock(dl);
303 zfs_dirent_unlock(dl);
306 error = zfs_zget(zfsvfs, zoid, zpp);
308 zfs_dirent_unlock(dl);
311 if (!(flag & ZXATTR) && update)
312 dnlc_update(ZTOV(dzp), name, ZTOV(*zpp));
321 * Unlock this directory entry and wake anyone who was waiting for it.
324 zfs_dirent_unlock(zfs_dirlock_t *dl)
326 znode_t *dzp = dl->dl_dzp;
327 zfs_dirlock_t **prev_dl, *cur_dl;
329 mutex_enter(&dzp->z_lock);
330 rw_exit(&dzp->z_name_lock);
331 if (dl->dl_sharecnt > 1) {
333 mutex_exit(&dzp->z_lock);
336 prev_dl = &dzp->z_dirlocks;
337 while ((cur_dl = *prev_dl) != dl)
338 prev_dl = &cur_dl->dl_next;
339 *prev_dl = dl->dl_next;
340 cv_broadcast(&dl->dl_cv);
341 mutex_exit(&dzp->z_lock);
343 if (dl->dl_namesize != 0)
344 kmem_free(dl->dl_name, dl->dl_namesize);
345 cv_destroy(&dl->dl_cv);
346 kmem_free(dl, sizeof (*dl));
350 * Look up an entry in a directory.
352 * NOTE: '.' and '..' are handled as special cases because
353 * no directory entries are actually stored for them. If this is
354 * the root of a filesystem, then '.zfs' is also treated as a
355 * special pseudo-directory.
358 zfs_dirlook(znode_t *dzp, char *name, vnode_t **vpp, int flags,
359 int *deflg, pathname_t *rpnp)
365 if (name[0] == 0 || (name[0] == '.' && name[1] == 0)) {
368 } else if (name[0] == '.' && name[1] == '.' && name[2] == 0) {
369 zfsvfs_t *zfsvfs = dzp->z_zfsvfs;
371 * If we are a snapshot mounted under .zfs, return
372 * the vp for the snapshot directory.
374 if (dzp->z_phys->zp_parent == dzp->z_id &&
375 zfsvfs->z_parent != zfsvfs) {
376 error = zfsctl_root_lookup(zfsvfs->z_parent->z_ctldir,
377 "snapshot", vpp, NULL, 0, NULL, kcred,
381 rw_enter(&dzp->z_parent_lock, RW_READER);
382 error = zfs_zget(zfsvfs, dzp->z_phys->zp_parent, &zp);
385 rw_exit(&dzp->z_parent_lock);
386 } else if (zfs_has_ctldir(dzp) && strcmp(name, ZFS_CTLDIR_NAME) == 0) {
387 *vpp = zfsctl_root(dzp);
391 zf = ZEXISTS | ZSHARED;
392 if (flags & FIGNORECASE)
395 error = zfs_dirent_lock(&dl, dzp, name, &zp, zf, deflg, rpnp);
398 zfs_dirent_unlock(dl);
399 dzp->z_zn_prefetch = B_TRUE; /* enable prefetching */
404 if ((flags & FIGNORECASE) && rpnp && !error)
405 (void) strlcpy(rpnp->pn_buf, name, rpnp->pn_bufsize);
411 zfs_unlinked_hexname(char namebuf[17], uint64_t x)
413 char *name = &namebuf[16];
414 const char digits[16] = "0123456789abcdef";
418 *--name = digits[x & 0xf];
426 * unlinked Set (formerly known as the "delete queue") Error Handling
428 * When dealing with the unlinked set, we dmu_tx_hold_zap(), but we
429 * don't specify the name of the entry that we will be manipulating. We
430 * also fib and say that we won't be adding any new entries to the
431 * unlinked set, even though we might (this is to lower the minimum file
432 * size that can be deleted in a full filesystem). So on the small
433 * chance that the nlink list is using a fat zap (ie. has more than
434 * 2000 entries), we *may* not pre-read a block that's needed.
435 * Therefore it is remotely possible for some of the assertions
436 * regarding the unlinked set below to fail due to i/o error. On a
437 * nondebug system, this will result in the space being leaked.
440 zfs_unlinked_add(znode_t *zp, dmu_tx_t *tx)
442 zfsvfs_t *zfsvfs = zp->z_zfsvfs;
446 ASSERT(zp->z_unlinked);
447 ASSERT3U(zp->z_phys->zp_links, ==, 0);
449 error = zap_add(zfsvfs->z_os, zfsvfs->z_unlinkedobj,
450 zfs_unlinked_hexname(obj_name, zp->z_id), 8, 1, &zp->z_id, tx);
451 ASSERT3U(error, ==, 0);
455 * Clean up any znodes that had no links when we either crashed or
456 * (force) umounted the file system.
459 zfs_unlinked_drain(zfsvfs_t *zfsvfs)
463 dmu_object_info_t doi;
468 * Interate over the contents of the unlinked set.
470 for (zap_cursor_init(&zc, zfsvfs->z_os, zfsvfs->z_unlinkedobj);
471 zap_cursor_retrieve(&zc, &zap) == 0;
472 zap_cursor_advance(&zc)) {
475 * See what kind of object we have in list
478 error = dmu_object_info(zfsvfs->z_os,
479 zap.za_first_integer, &doi);
483 ASSERT((doi.doi_type == DMU_OT_PLAIN_FILE_CONTENTS) ||
484 (doi.doi_type == DMU_OT_DIRECTORY_CONTENTS));
486 * We need to re-mark these list entries for deletion,
487 * so we pull them back into core and set zp->z_unlinked.
489 error = zfs_zget(zfsvfs, zap.za_first_integer, &zp);
492 * We may pick up znodes that are already marked for deletion.
493 * This could happen during the purge of an extended attribute
494 * directory. All we need to do is skip over them, since they
495 * are already in the system marked z_unlinked.
500 zp->z_unlinked = B_TRUE;
503 zap_cursor_fini(&zc);
507 * Delete the entire contents of a directory. Return a count
508 * of the number of entries that could not be deleted. If we encounter
509 * an error, return a count of at least one so that the directory stays
510 * in the unlinked set.
512 * NOTE: this function assumes that the directory is inactive,
513 * so there is no need to lock its entries before deletion.
514 * Also, it assumes the directory contents is *only* regular
518 zfs_purgedir(znode_t *dzp)
524 zfsvfs_t *zfsvfs = dzp->z_zfsvfs;
529 for (zap_cursor_init(&zc, zfsvfs->z_os, dzp->z_id);
530 (error = zap_cursor_retrieve(&zc, &zap)) == 0;
531 zap_cursor_advance(&zc)) {
532 error = zfs_zget(zfsvfs,
533 ZFS_DIRENT_OBJ(zap.za_first_integer), &xzp);
539 ASSERT((ZTOV(xzp)->v_type == VREG) ||
540 (ZTOV(xzp)->v_type == VLNK));
542 tx = dmu_tx_create(zfsvfs->z_os);
543 dmu_tx_hold_bonus(tx, dzp->z_id);
544 dmu_tx_hold_zap(tx, dzp->z_id, FALSE, zap.za_name);
545 dmu_tx_hold_bonus(tx, xzp->z_id);
546 dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
547 error = dmu_tx_assign(tx, TXG_WAIT);
554 bzero(&dl, sizeof (dl));
556 dl.dl_name = zap.za_name;
558 error = zfs_link_destroy(&dl, xzp, tx, 0, NULL);
565 zap_cursor_fini(&zc);
572 zfs_rmnode(znode_t *zp)
574 zfsvfs_t *zfsvfs = zp->z_zfsvfs;
575 objset_t *os = zfsvfs->z_os;
582 ASSERT(ZTOV(zp)->v_count == 0);
583 ASSERT(zp->z_phys->zp_links == 0);
586 * If this is an attribute directory, purge its contents.
588 if (ZTOV(zp)->v_type == VDIR && (zp->z_phys->zp_flags & ZFS_XATTR)) {
589 if (zfs_purgedir(zp) != 0) {
591 * Not enough space to delete some xattrs.
592 * Leave it on the unlinked set.
594 zfs_znode_dmu_fini(zp);
601 * If the file has extended attributes, we're going to unlink
604 if (zp->z_phys->zp_xattr) {
605 error = zfs_zget(zfsvfs, zp->z_phys->zp_xattr, &xzp);
609 acl_obj = zp->z_phys->zp_acl.z_acl_extern_obj;
612 * Set up the transaction.
614 tx = dmu_tx_create(os);
615 dmu_tx_hold_free(tx, zp->z_id, 0, DMU_OBJECT_END);
616 dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
618 dmu_tx_hold_bonus(tx, xzp->z_id);
619 dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, TRUE, NULL);
622 dmu_tx_hold_free(tx, acl_obj, 0, DMU_OBJECT_END);
623 error = dmu_tx_assign(tx, TXG_WAIT);
626 * Not enough space to delete the file. Leave it in the
627 * unlinked set, leaking it until the fs is remounted (at
628 * which point we'll call zfs_unlinked_drain() to process it).
631 zfs_znode_dmu_fini(zp);
637 dmu_buf_will_dirty(xzp->z_dbuf, tx);
638 mutex_enter(&xzp->z_lock);
639 xzp->z_unlinked = B_TRUE; /* mark xzp for deletion */
640 xzp->z_phys->zp_links = 0; /* no more links to it */
641 mutex_exit(&xzp->z_lock);
642 zfs_unlinked_add(xzp, tx);
645 /* Remove this znode from the unlinked set */
646 error = zap_remove(os, zfsvfs->z_unlinkedobj,
647 zfs_unlinked_hexname(obj_name, zp->z_id), tx);
648 ASSERT3U(error, ==, 0);
650 zfs_znode_delete(zp, tx);
659 zfs_dirent(znode_t *zp)
661 uint64_t de = zp->z_id;
662 if (zp->z_zfsvfs->z_version >= ZPL_VERSION_DIRENT_TYPE)
663 de |= IFTODT((zp)->z_phys->zp_mode) << 60;
668 * Link zp into dl. Can only fail if zp has been unlinked.
671 zfs_link_create(zfs_dirlock_t *dl, znode_t *zp, dmu_tx_t *tx, int flag)
673 znode_t *dzp = dl->dl_dzp;
674 vnode_t *vp = ZTOV(zp);
676 int zp_is_dir = (vp->v_type == VDIR);
679 dmu_buf_will_dirty(zp->z_dbuf, tx);
680 mutex_enter(&zp->z_lock);
682 if (!(flag & ZRENAMING)) {
683 if (zp->z_unlinked) { /* no new links to unlinked zp */
684 ASSERT(!(flag & (ZNEW | ZEXISTS)));
685 mutex_exit(&zp->z_lock);
688 zp->z_phys->zp_links++;
690 zp->z_phys->zp_parent = dzp->z_id; /* dzp is now zp's parent */
693 zfs_time_stamper_locked(zp, STATE_CHANGED, tx);
694 mutex_exit(&zp->z_lock);
696 dmu_buf_will_dirty(dzp->z_dbuf, tx);
697 mutex_enter(&dzp->z_lock);
698 dzp->z_phys->zp_size++; /* one dirent added */
699 dzp->z_phys->zp_links += zp_is_dir; /* ".." link from zp */
700 zfs_time_stamper_locked(dzp, CONTENT_MODIFIED, tx);
701 mutex_exit(&dzp->z_lock);
703 value = zfs_dirent(zp);
704 error = zap_add(zp->z_zfsvfs->z_os, dzp->z_id, dl->dl_name,
708 dnlc_update(ZTOV(dzp), dl->dl_name, vp);
714 * Unlink zp from dl, and mark zp for deletion if this was the last link.
715 * Can fail if zp is a mount point (EBUSY) or a non-empty directory (EEXIST).
716 * If 'unlinkedp' is NULL, we put unlinked znodes on the unlinked list.
717 * If it's non-NULL, we use it to indicate whether the znode needs deletion,
718 * and it's the caller's job to do it.
721 zfs_link_destroy(zfs_dirlock_t *dl, znode_t *zp, dmu_tx_t *tx, int flag,
722 boolean_t *unlinkedp)
724 znode_t *dzp = dl->dl_dzp;
725 vnode_t *vp = ZTOV(zp);
726 int zp_is_dir = (vp->v_type == VDIR);
727 boolean_t unlinked = B_FALSE;
730 dnlc_remove(ZTOV(dzp), dl->dl_name);
732 if (!(flag & ZRENAMING)) {
733 dmu_buf_will_dirty(zp->z_dbuf, tx);
735 if (vn_vfswlock(vp)) /* prevent new mounts on zp */
738 if (vn_ismntpt(vp)) { /* don't remove mount point */
743 mutex_enter(&zp->z_lock);
744 if (zp_is_dir && !zfs_dirempty(zp)) { /* dir not empty */
745 mutex_exit(&zp->z_lock);
749 if (zp->z_phys->zp_links <= zp_is_dir) {
750 zfs_panic_recover("zfs: link count on %s is %u, "
751 "should be at least %u",
752 zp->z_vnode->v_path ? zp->z_vnode->v_path :
753 "<unknown>", (int)zp->z_phys->zp_links,
755 zp->z_phys->zp_links = zp_is_dir + 1;
757 if (--zp->z_phys->zp_links == zp_is_dir) {
758 zp->z_unlinked = B_TRUE;
759 zp->z_phys->zp_links = 0;
762 zfs_time_stamper_locked(zp, STATE_CHANGED, tx);
764 mutex_exit(&zp->z_lock);
768 dmu_buf_will_dirty(dzp->z_dbuf, tx);
769 mutex_enter(&dzp->z_lock);
770 dzp->z_phys->zp_size--; /* one dirent removed */
771 dzp->z_phys->zp_links -= zp_is_dir; /* ".." link from zp */
772 zfs_time_stamper_locked(dzp, CONTENT_MODIFIED, tx);
773 mutex_exit(&dzp->z_lock);
775 if (zp->z_zfsvfs->z_norm) {
776 if (((zp->z_zfsvfs->z_case == ZFS_CASE_INSENSITIVE) &&
777 (flag & ZCIEXACT)) ||
778 ((zp->z_zfsvfs->z_case == ZFS_CASE_MIXED) &&
780 error = zap_remove_norm(zp->z_zfsvfs->z_os,
781 dzp->z_id, dl->dl_name, MT_EXACT, tx);
783 error = zap_remove_norm(zp->z_zfsvfs->z_os,
784 dzp->z_id, dl->dl_name, MT_FIRST, tx);
786 error = zap_remove(zp->z_zfsvfs->z_os,
787 dzp->z_id, dl->dl_name, tx);
791 if (unlinkedp != NULL)
792 *unlinkedp = unlinked;
794 zfs_unlinked_add(zp, tx);
800 * Indicate whether the directory is empty. Works with or without z_lock
801 * held, but can only be consider a hint in the latter case. Returns true
802 * if only "." and ".." remain and there's no work in progress.
805 zfs_dirempty(znode_t *dzp)
807 return (dzp->z_phys->zp_size == 2 && dzp->z_dirlocks == 0);
811 zfs_make_xattrdir(znode_t *zp, vattr_t *vap, vnode_t **xvpp, cred_t *cr)
813 zfsvfs_t *zfsvfs = zp->z_zfsvfs;
817 zfs_fuid_info_t *fuidp = NULL;
821 if (error = zfs_zaccess(zp, ACE_WRITE_NAMED_ATTRS, 0, B_FALSE, cr))
824 tx = dmu_tx_create(zfsvfs->z_os);
825 dmu_tx_hold_bonus(tx, zp->z_id);
826 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, FALSE, NULL);
827 if (IS_EPHEMERAL(crgetuid(cr)) || IS_EPHEMERAL(crgetgid(cr))) {
828 if (zfsvfs->z_fuid_obj == 0) {
829 dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT);
830 dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0,
831 FUID_SIZE_ESTIMATE(zfsvfs));
832 dmu_tx_hold_zap(tx, MASTER_NODE_OBJ, FALSE, NULL);
834 dmu_tx_hold_bonus(tx, zfsvfs->z_fuid_obj);
835 dmu_tx_hold_write(tx, zfsvfs->z_fuid_obj, 0,
836 FUID_SIZE_ESTIMATE(zfsvfs));
839 error = dmu_tx_assign(tx, zfsvfs->z_assign);
841 if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT)
846 zfs_mknode(zp, vap, tx, cr, IS_XATTR, &xzp, 0, NULL, &fuidp);
847 ASSERT(xzp->z_phys->zp_parent == zp->z_id);
848 dmu_buf_will_dirty(zp->z_dbuf, tx);
849 zp->z_phys->zp_xattr = xzp->z_id;
851 (void) zfs_log_create(zfsvfs->z_log, tx, TX_MKXATTR, zp,
852 xzp, "", NULL, fuidp, vap);
854 zfs_fuid_info_free(fuidp);
863 * Return a znode for the extended attribute directory for zp.
864 * ** If the directory does not already exist, it is created **
866 * IN: zp - znode to obtain attribute directory from
867 * cr - credentials of caller
868 * flags - flags from the VOP_LOOKUP call
870 * OUT: xzpp - pointer to extended attribute znode
872 * RETURN: 0 on success
873 * error number on failure
876 zfs_get_xattrdir(znode_t *zp, vnode_t **xvpp, cred_t *cr, int flags)
878 zfsvfs_t *zfsvfs = zp->z_zfsvfs;
884 error = zfs_dirent_lock(&dl, zp, "", &xzp, ZXATTR, NULL, NULL);
890 zfs_dirent_unlock(dl);
894 ASSERT(zp->z_phys->zp_xattr == 0);
896 if (!(flags & CREATE_XATTR_DIR)) {
897 zfs_dirent_unlock(dl);
901 if (zfsvfs->z_vfs->vfs_flag & VFS_RDONLY) {
902 zfs_dirent_unlock(dl);
907 * The ability to 'create' files in an attribute
908 * directory comes from the write_xattr permission on the base file.
910 * The ability to 'search' an attribute directory requires
911 * read_xattr permission on the base file.
913 * Once in a directory the ability to read/write attributes
914 * is controlled by the permissions on the attribute file.
916 va.va_mask = AT_TYPE | AT_MODE | AT_UID | AT_GID;
918 va.va_mode = S_IFDIR | S_ISVTX | 0777;
919 zfs_fuid_map_ids(zp, cr, &va.va_uid, &va.va_gid);
921 error = zfs_make_xattrdir(zp, &va, xvpp, cr);
922 zfs_dirent_unlock(dl);
924 if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
925 /* NB: we already did dmu_tx_wait() if necessary */
933 * Decide whether it is okay to remove within a sticky directory.
935 * In sticky directories, write access is not sufficient;
936 * you can remove entries from a directory only if:
938 * you own the directory,
940 * the entry is a plain file and you have write access,
941 * or you are privileged (checked in secpolicy...).
943 * The function returns 0 if remove access is granted.
946 zfs_sticky_remove_access(znode_t *zdp, znode_t *zp, cred_t *cr)
951 zfsvfs_t *zfsvfs = zdp->z_zfsvfs;
953 if (zdp->z_zfsvfs->z_assign >= TXG_INITIAL) /* ZIL replay */
956 if ((zdp->z_phys->zp_mode & S_ISVTX) == 0)
959 downer = zfs_fuid_map_id(zfsvfs, zdp->z_phys->zp_uid, cr, ZFS_OWNER);
960 fowner = zfs_fuid_map_id(zfsvfs, zp->z_phys->zp_uid, cr, ZFS_OWNER);
962 if ((uid = crgetuid(cr)) == downer || uid == fowner ||
963 (ZTOV(zp)->v_type == VREG &&
964 zfs_zaccess(zp, ACE_WRITE_DATA, 0, B_FALSE, cr) == 0))
967 return (secpolicy_vnode_remove(cr));