1 /*
2 * CDDL HEADER START
3 *
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.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or https://opensource.org/licenses/CDDL-1.0.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
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]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Copyright (c) 2013, 2016 by Delphix. All rights reserved.
25 * Copyright 2017 Nexenta Systems, Inc.
26 */
27
28 #include <sys/types.h>
29 #include <sys/param.h>
30 #include <sys/time.h>
31 #include <sys/systm.h>
32 #include <sys/sysmacros.h>
33 #include <sys/resource.h>
34 #include <sys/vfs.h>
35 #include <sys/vnode.h>
36 #include <sys/file.h>
37 #include <sys/kmem.h>
38 #include <sys/uio.h>
39 #include <sys/cmn_err.h>
40 #include <sys/errno.h>
41 #include <sys/stat.h>
42 #include <sys/unistd.h>
43 #include <sys/sunddi.h>
44 #include <sys/random.h>
45 #include <sys/policy.h>
46 #include <sys/condvar.h>
47 #include <sys/callb.h>
48 #include <sys/smp.h>
49 #include <sys/zfs_dir.h>
50 #include <sys/zfs_acl.h>
51 #include <sys/fs/zfs.h>
52 #include <sys/zap.h>
53 #include <sys/dmu.h>
54 #include <sys/atomic.h>
55 #include <sys/zfs_ctldir.h>
56 #include <sys/zfs_fuid.h>
57 #include <sys/sa.h>
58 #include <sys/zfs_sa.h>
59 #include <sys/dmu_objset.h>
60 #include <sys/dsl_dir.h>
61
62 #include <sys/ccompat.h>
63
64 /*
65 * zfs_match_find() is used by zfs_dirent_lookup() to perform zap lookups
66 * of names after deciding which is the appropriate lookup interface.
67 */
68 static int
zfs_match_find(zfsvfs_t * zfsvfs,znode_t * dzp,const char * name,matchtype_t mt,uint64_t * zoid)69 zfs_match_find(zfsvfs_t *zfsvfs, znode_t *dzp, const char *name,
70 matchtype_t mt, uint64_t *zoid)
71 {
72 int error;
73
74 if (zfsvfs->z_norm) {
75
76 /*
77 * In the non-mixed case we only expect there would ever
78 * be one match, but we need to use the normalizing lookup.
79 */
80 error = zap_lookup_norm(zfsvfs->z_os, dzp->z_id, name, 8, 1,
81 zoid, mt, NULL, 0, NULL);
82 } else {
83 error = zap_lookup(zfsvfs->z_os, dzp->z_id, name, 8, 1, zoid);
84 }
85 *zoid = ZFS_DIRENT_OBJ(*zoid);
86
87 return (error);
88 }
89
90 /*
91 * Look up a directory entry under a locked vnode.
92 * dvp being locked gives us a guarantee that there are no concurrent
93 * modification of the directory and, thus, if a node can be found in
94 * the directory, then it must not be unlinked.
95 *
96 * Input arguments:
97 * dzp - znode for directory
98 * name - name of entry to lock
99 * flag - ZNEW: if the entry already exists, fail with EEXIST.
100 * ZEXISTS: if the entry does not exist, fail with ENOENT.
101 * ZXATTR: we want dzp's xattr directory
102 *
103 * Output arguments:
104 * zpp - pointer to the znode for the entry (NULL if there isn't one)
105 *
106 * Return value: 0 on success or errno on failure.
107 *
108 * NOTE: Always checks for, and rejects, '.' and '..'.
109 */
110 int
zfs_dirent_lookup(znode_t * dzp,const char * name,znode_t ** zpp,int flag)111 zfs_dirent_lookup(znode_t *dzp, const char *name, znode_t **zpp, int flag)
112 {
113 zfsvfs_t *zfsvfs = dzp->z_zfsvfs;
114 znode_t *zp;
115 matchtype_t mt = 0;
116 uint64_t zoid;
117 int error = 0;
118
119 if (zfsvfs->z_replay == B_FALSE)
120 ASSERT_VOP_LOCKED(ZTOV(dzp), __func__);
121
122 *zpp = NULL;
123
124 /*
125 * Verify that we are not trying to lock '.', '..', or '.zfs'
126 */
127 if (name[0] == '.' &&
128 (((name[1] == '\0') || (name[1] == '.' && name[2] == '\0')) ||
129 (zfs_has_ctldir(dzp) && strcmp(name, ZFS_CTLDIR_NAME) == 0)))
130 return (SET_ERROR(EEXIST));
131
132 /*
133 * Case sensitivity and normalization preferences are set when
134 * the file system is created. These are stored in the
135 * zfsvfs->z_case and zfsvfs->z_norm fields. These choices
136 * affect how we perform zap lookups.
137 *
138 * When matching we may need to normalize & change case according to
139 * FS settings.
140 *
141 * Note that a normalized match is necessary for a case insensitive
142 * filesystem when the lookup request is not exact because normalization
143 * can fold case independent of normalizing code point sequences.
144 *
145 * See the table above zfs_dropname().
146 */
147 if (zfsvfs->z_norm != 0) {
148 mt = MT_NORMALIZE;
149
150 /*
151 * Determine if the match needs to honor the case specified in
152 * lookup, and if so keep track of that so that during
153 * normalization we don't fold case.
154 */
155 if (zfsvfs->z_case == ZFS_CASE_MIXED) {
156 mt |= MT_MATCH_CASE;
157 }
158 }
159
160 /*
161 * Only look in or update the DNLC if we are looking for the
162 * name on a file system that does not require normalization
163 * or case folding. We can also look there if we happen to be
164 * on a non-normalizing, mixed sensitivity file system IF we
165 * are looking for the exact name.
166 *
167 * NB: we do not need to worry about this flag for ZFS_CASE_SENSITIVE
168 * because in that case MT_EXACT and MT_FIRST should produce exactly
169 * the same result.
170 */
171
172 if (dzp->z_unlinked && !(flag & ZXATTR))
173 return (ENOENT);
174 if (flag & ZXATTR) {
175 error = sa_lookup(dzp->z_sa_hdl, SA_ZPL_XATTR(zfsvfs), &zoid,
176 sizeof (zoid));
177 if (error == 0)
178 error = (zoid == 0 ? ENOENT : 0);
179 } else {
180 error = zfs_match_find(zfsvfs, dzp, name, mt, &zoid);
181 }
182 if (error) {
183 if (error != ENOENT || (flag & ZEXISTS)) {
184 return (error);
185 }
186 } else {
187 if (flag & ZNEW) {
188 return (SET_ERROR(EEXIST));
189 }
190 error = zfs_zget(zfsvfs, zoid, &zp);
191 if (error)
192 return (error);
193 ASSERT(!zp->z_unlinked);
194 *zpp = zp;
195 }
196
197 return (0);
198 }
199
200 static int
zfs_dd_lookup(znode_t * dzp,znode_t ** zpp)201 zfs_dd_lookup(znode_t *dzp, znode_t **zpp)
202 {
203 zfsvfs_t *zfsvfs = dzp->z_zfsvfs;
204 znode_t *zp;
205 uint64_t parent;
206 int error;
207
208 #ifdef ZFS_DEBUG
209 if (zfsvfs->z_replay == B_FALSE)
210 ASSERT_VOP_LOCKED(ZTOV(dzp), __func__);
211 #endif
212 if (dzp->z_unlinked)
213 return (ENOENT);
214
215 if ((error = sa_lookup(dzp->z_sa_hdl,
216 SA_ZPL_PARENT(zfsvfs), &parent, sizeof (parent))) != 0)
217 return (error);
218
219 error = zfs_zget(zfsvfs, parent, &zp);
220 if (error == 0)
221 *zpp = zp;
222 return (error);
223 }
224
225 int
zfs_dirlook(znode_t * dzp,const char * name,znode_t ** zpp)226 zfs_dirlook(znode_t *dzp, const char *name, znode_t **zpp)
227 {
228 zfsvfs_t *zfsvfs __unused = dzp->z_zfsvfs;
229 znode_t *zp = NULL;
230 int error = 0;
231
232 #ifdef ZFS_DEBUG
233 if (zfsvfs->z_replay == B_FALSE)
234 ASSERT_VOP_LOCKED(ZTOV(dzp), __func__);
235 #endif
236 if (dzp->z_unlinked)
237 return (SET_ERROR(ENOENT));
238
239 if (name[0] == 0 || (name[0] == '.' && name[1] == 0)) {
240 *zpp = dzp;
241 } else if (name[0] == '.' && name[1] == '.' && name[2] == 0) {
242 error = zfs_dd_lookup(dzp, &zp);
243 if (error == 0)
244 *zpp = zp;
245 } else {
246 error = zfs_dirent_lookup(dzp, name, &zp, ZEXISTS);
247 if (error == 0) {
248 dzp->z_zn_prefetch = B_TRUE; /* enable prefetching */
249 *zpp = zp;
250 }
251 }
252 return (error);
253 }
254
255 /*
256 * unlinked Set (formerly known as the "delete queue") Error Handling
257 *
258 * When dealing with the unlinked set, we dmu_tx_hold_zap(), but we
259 * don't specify the name of the entry that we will be manipulating. We
260 * also fib and say that we won't be adding any new entries to the
261 * unlinked set, even though we might (this is to lower the minimum file
262 * size that can be deleted in a full filesystem). So on the small
263 * chance that the nlink list is using a fat zap (ie. has more than
264 * 2000 entries), we *may* not pre-read a block that's needed.
265 * Therefore it is remotely possible for some of the assertions
266 * regarding the unlinked set below to fail due to i/o error. On a
267 * nondebug system, this will result in the space being leaked.
268 */
269 void
zfs_unlinked_add(znode_t * zp,dmu_tx_t * tx)270 zfs_unlinked_add(znode_t *zp, dmu_tx_t *tx)
271 {
272 zfsvfs_t *zfsvfs = zp->z_zfsvfs;
273
274 ASSERT(zp->z_unlinked);
275 ASSERT3U(zp->z_links, ==, 0);
276
277 VERIFY0(zap_add_int(zfsvfs->z_os, zfsvfs->z_unlinkedobj, zp->z_id, tx));
278
279 dataset_kstats_update_nunlinks_kstat(&zfsvfs->z_kstat, 1);
280 }
281
282 /*
283 * Clean up any znodes that had no links when we either crashed or
284 * (force) umounted the file system.
285 */
286 void
zfs_unlinked_drain(zfsvfs_t * zfsvfs)287 zfs_unlinked_drain(zfsvfs_t *zfsvfs)
288 {
289 zap_cursor_t zc;
290 zap_attribute_t *zap;
291 dmu_object_info_t doi;
292 znode_t *zp;
293 dmu_tx_t *tx;
294 int error;
295
296 /*
297 * Iterate over the contents of the unlinked set.
298 */
299 zap = zap_attribute_alloc();
300 for (zap_cursor_init(&zc, zfsvfs->z_os, zfsvfs->z_unlinkedobj);
301 zap_cursor_retrieve(&zc, zap) == 0;
302 zap_cursor_advance(&zc)) {
303
304 /*
305 * See what kind of object we have in list
306 */
307
308 error = dmu_object_info(zfsvfs->z_os,
309 zap->za_first_integer, &doi);
310 if (error != 0)
311 continue;
312
313 ASSERT((doi.doi_type == DMU_OT_PLAIN_FILE_CONTENTS) ||
314 (doi.doi_type == DMU_OT_DIRECTORY_CONTENTS));
315 /*
316 * We need to re-mark these list entries for deletion,
317 * so we pull them back into core and set zp->z_unlinked.
318 */
319 error = zfs_zget(zfsvfs, zap->za_first_integer, &zp);
320
321 /*
322 * We may pick up znodes that are already marked for deletion.
323 * This could happen during the purge of an extended attribute
324 * directory. All we need to do is skip over them, since they
325 * are already in the system marked z_unlinked.
326 */
327 if (error != 0)
328 continue;
329
330 vn_lock(ZTOV(zp), LK_EXCLUSIVE | LK_RETRY);
331
332 /*
333 * Due to changes in zfs_rmnode we need to make sure the
334 * link count is set to zero here.
335 */
336 if (zp->z_links != 0) {
337 tx = dmu_tx_create(zfsvfs->z_os);
338 dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_FALSE);
339 error = dmu_tx_assign(tx, TXG_WAIT);
340 if (error != 0) {
341 dmu_tx_abort(tx);
342 vput(ZTOV(zp));
343 continue;
344 }
345 zp->z_links = 0;
346 VERIFY0(sa_update(zp->z_sa_hdl, SA_ZPL_LINKS(zfsvfs),
347 &zp->z_links, sizeof (zp->z_links), tx));
348 dmu_tx_commit(tx);
349 }
350
351 zp->z_unlinked = B_TRUE;
352 vput(ZTOV(zp));
353 }
354 zap_cursor_fini(&zc);
355 zap_attribute_free(zap);
356 }
357
358 /*
359 * Delete the entire contents of a directory. Return a count
360 * of the number of entries that could not be deleted. If we encounter
361 * an error, return a count of at least one so that the directory stays
362 * in the unlinked set.
363 *
364 * NOTE: this function assumes that the directory is inactive,
365 * so there is no need to lock its entries before deletion.
366 * Also, it assumes the directory contents is *only* regular
367 * files.
368 */
369 static int
zfs_purgedir(znode_t * dzp)370 zfs_purgedir(znode_t *dzp)
371 {
372 zap_cursor_t zc;
373 zap_attribute_t *zap;
374 znode_t *xzp;
375 dmu_tx_t *tx;
376 zfsvfs_t *zfsvfs = dzp->z_zfsvfs;
377 int skipped = 0;
378 int error;
379
380 zap = zap_attribute_alloc();
381 for (zap_cursor_init(&zc, zfsvfs->z_os, dzp->z_id);
382 (error = zap_cursor_retrieve(&zc, zap)) == 0;
383 zap_cursor_advance(&zc)) {
384 error = zfs_zget(zfsvfs,
385 ZFS_DIRENT_OBJ(zap->za_first_integer), &xzp);
386 if (error) {
387 skipped += 1;
388 continue;
389 }
390
391 vn_lock(ZTOV(xzp), LK_EXCLUSIVE | LK_RETRY);
392 ASSERT((ZTOV(xzp)->v_type == VREG) ||
393 (ZTOV(xzp)->v_type == VLNK));
394
395 tx = dmu_tx_create(zfsvfs->z_os);
396 dmu_tx_hold_sa(tx, dzp->z_sa_hdl, B_FALSE);
397 dmu_tx_hold_zap(tx, dzp->z_id, FALSE, zap->za_name);
398 dmu_tx_hold_sa(tx, xzp->z_sa_hdl, B_FALSE);
399 dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
400 /* Is this really needed ? */
401 zfs_sa_upgrade_txholds(tx, xzp);
402 dmu_tx_mark_netfree(tx);
403 error = dmu_tx_assign(tx, TXG_WAIT);
404 if (error) {
405 dmu_tx_abort(tx);
406 vput(ZTOV(xzp));
407 skipped += 1;
408 continue;
409 }
410
411 error = zfs_link_destroy(dzp, zap->za_name, xzp, tx, 0, NULL);
412 if (error)
413 skipped += 1;
414 dmu_tx_commit(tx);
415
416 vput(ZTOV(xzp));
417 }
418 zap_cursor_fini(&zc);
419 zap_attribute_free(zap);
420 if (error != ENOENT)
421 skipped += 1;
422 return (skipped);
423 }
424
425 extern taskq_t *zfsvfs_taskq;
426
427 void
zfs_rmnode(znode_t * zp)428 zfs_rmnode(znode_t *zp)
429 {
430 zfsvfs_t *zfsvfs = zp->z_zfsvfs;
431 objset_t *os = zfsvfs->z_os;
432 dmu_tx_t *tx;
433 uint64_t z_id = zp->z_id;
434 uint64_t acl_obj;
435 uint64_t xattr_obj;
436 uint64_t count;
437 int error;
438
439 ASSERT3U(zp->z_links, ==, 0);
440 if (zfsvfs->z_replay == B_FALSE)
441 ASSERT_VOP_ELOCKED(ZTOV(zp), __func__);
442
443 /*
444 * If this is an attribute directory, purge its contents.
445 */
446 if (ZTOV(zp) != NULL && ZTOV(zp)->v_type == VDIR &&
447 (zp->z_pflags & ZFS_XATTR)) {
448 if (zfs_purgedir(zp) != 0) {
449 /*
450 * Not enough space to delete some xattrs.
451 * Leave it in the unlinked set.
452 */
453 ZFS_OBJ_HOLD_ENTER(zfsvfs, z_id);
454 zfs_znode_dmu_fini(zp);
455 zfs_znode_free(zp);
456 ZFS_OBJ_HOLD_EXIT(zfsvfs, z_id);
457 return;
458 }
459 } else {
460 /*
461 * Free up all the data in the file. We don't do this for
462 * XATTR directories because we need truncate and remove to be
463 * in the same tx, like in zfs_znode_delete(). Otherwise, if
464 * we crash here we'll end up with an inconsistent truncated
465 * zap object in the delete queue. Note a truncated file is
466 * harmless since it only contains user data.
467 */
468 error = dmu_free_long_range(os, zp->z_id, 0, DMU_OBJECT_END);
469 if (error) {
470 /*
471 * Not enough space or we were interrupted by unmount.
472 * Leave the file in the unlinked set.
473 */
474 ZFS_OBJ_HOLD_ENTER(zfsvfs, z_id);
475 zfs_znode_dmu_fini(zp);
476 zfs_znode_free(zp);
477 ZFS_OBJ_HOLD_EXIT(zfsvfs, z_id);
478 return;
479 }
480 }
481
482 /*
483 * If the file has extended attributes, we're going to unlink
484 * the xattr dir.
485 */
486 error = sa_lookup(zp->z_sa_hdl, SA_ZPL_XATTR(zfsvfs),
487 &xattr_obj, sizeof (xattr_obj));
488 if (error)
489 xattr_obj = 0;
490
491 acl_obj = zfs_external_acl(zp);
492
493 /*
494 * Set up the final transaction.
495 */
496 tx = dmu_tx_create(os);
497 dmu_tx_hold_free(tx, zp->z_id, 0, DMU_OBJECT_END);
498 dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
499 if (xattr_obj)
500 dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, TRUE, NULL);
501 if (acl_obj)
502 dmu_tx_hold_free(tx, acl_obj, 0, DMU_OBJECT_END);
503
504 zfs_sa_upgrade_txholds(tx, zp);
505 error = dmu_tx_assign(tx, TXG_WAIT);
506 if (error) {
507 /*
508 * Not enough space to delete the file. Leave it in the
509 * unlinked set, leaking it until the fs is remounted (at
510 * which point we'll call zfs_unlinked_drain() to process it).
511 */
512 dmu_tx_abort(tx);
513 ZFS_OBJ_HOLD_ENTER(zfsvfs, z_id);
514 zfs_znode_dmu_fini(zp);
515 zfs_znode_free(zp);
516 ZFS_OBJ_HOLD_EXIT(zfsvfs, z_id);
517 return;
518 }
519
520 /*
521 * FreeBSD's implementation of zfs_zget requires a vnode to back it.
522 * This means that we could end up calling into getnewvnode while
523 * calling zfs_rmnode as a result of a prior call to getnewvnode
524 * trying to clear vnodes out of the cache. If this repeats we can
525 * recurse enough that we overflow our stack. To avoid this, we
526 * avoid calling zfs_zget on the xattr znode and instead simply add
527 * it to the unlinked set and schedule a call to zfs_unlinked_drain.
528 */
529 if (xattr_obj) {
530 /* Add extended attribute directory to the unlinked set. */
531 VERIFY3U(0, ==,
532 zap_add_int(os, zfsvfs->z_unlinkedobj, xattr_obj, tx));
533 }
534
535 mutex_enter(&os->os_dsl_dataset->ds_dir->dd_activity_lock);
536
537 /* Remove this znode from the unlinked set */
538 VERIFY3U(0, ==,
539 zap_remove_int(os, zfsvfs->z_unlinkedobj, zp->z_id, tx));
540
541 if (zap_count(os, zfsvfs->z_unlinkedobj, &count) == 0 && count == 0) {
542 cv_broadcast(&os->os_dsl_dataset->ds_dir->dd_activity_cv);
543 }
544
545 mutex_exit(&os->os_dsl_dataset->ds_dir->dd_activity_lock);
546
547 dataset_kstats_update_nunlinked_kstat(&zfsvfs->z_kstat, 1);
548
549 zfs_znode_delete(zp, tx);
550 zfs_znode_free(zp);
551
552 dmu_tx_commit(tx);
553
554 if (xattr_obj) {
555 /*
556 * We're using the FreeBSD taskqueue API here instead of
557 * the Solaris taskq API since the FreeBSD API allows for a
558 * task to be enqueued multiple times but executed once.
559 */
560 taskqueue_enqueue(zfsvfs_taskq->tq_queue,
561 &zfsvfs->z_unlinked_drain_task);
562 }
563 }
564
565 static uint64_t
zfs_dirent(znode_t * zp,uint64_t mode)566 zfs_dirent(znode_t *zp, uint64_t mode)
567 {
568 uint64_t de = zp->z_id;
569
570 if (zp->z_zfsvfs->z_version >= ZPL_VERSION_DIRENT_TYPE)
571 de |= IFTODT(mode) << 60;
572 return (de);
573 }
574
575 /*
576 * Link zp into dzp. Can only fail if zp has been unlinked.
577 */
578 int
zfs_link_create(znode_t * dzp,const char * name,znode_t * zp,dmu_tx_t * tx,int flag)579 zfs_link_create(znode_t *dzp, const char *name, znode_t *zp, dmu_tx_t *tx,
580 int flag)
581 {
582 zfsvfs_t *zfsvfs = zp->z_zfsvfs;
583 vnode_t *vp = ZTOV(zp);
584 uint64_t value;
585 int zp_is_dir = (vp->v_type == VDIR);
586 sa_bulk_attr_t bulk[5];
587 uint64_t mtime[2], ctime[2];
588 int count = 0;
589 int error;
590
591 if (zfsvfs->z_replay == B_FALSE) {
592 ASSERT_VOP_ELOCKED(ZTOV(dzp), __func__);
593 ASSERT_VOP_ELOCKED(ZTOV(zp), __func__);
594 }
595 if (zp_is_dir) {
596 if (dzp->z_links >= ZFS_LINK_MAX)
597 return (SET_ERROR(EMLINK));
598 }
599 if (!(flag & ZRENAMING)) {
600 if (zp->z_unlinked) { /* no new links to unlinked zp */
601 ASSERT(!(flag & (ZNEW | ZEXISTS)));
602 return (SET_ERROR(ENOENT));
603 }
604 if (zp->z_links >= ZFS_LINK_MAX - zp_is_dir) {
605 return (SET_ERROR(EMLINK));
606 }
607 zp->z_links++;
608 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_LINKS(zfsvfs), NULL,
609 &zp->z_links, sizeof (zp->z_links));
610
611 } else {
612 ASSERT(!zp->z_unlinked);
613 }
614 value = zfs_dirent(zp, zp->z_mode);
615 error = zap_add(zp->z_zfsvfs->z_os, dzp->z_id, name,
616 8, 1, &value, tx);
617
618 /*
619 * zap_add could fail to add the entry if it exceeds the capacity of the
620 * leaf-block and zap_leaf_split() failed to help.
621 * The caller of this routine is responsible for failing the transaction
622 * which will rollback the SA updates done above.
623 */
624 if (error != 0) {
625 if (!(flag & ZRENAMING) && !(flag & ZNEW))
626 zp->z_links--;
627 return (error);
628 }
629
630 /*
631 * If we added a longname activate the SPA_FEATURE_LONGNAME.
632 */
633 if (strlen(name) >= ZAP_MAXNAMELEN) {
634 dsl_dataset_t *ds = dmu_objset_ds(zfsvfs->z_os);
635 ds->ds_feature_activation[SPA_FEATURE_LONGNAME] =
636 (void *)B_TRUE;
637 }
638
639 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_PARENT(zfsvfs), NULL,
640 &dzp->z_id, sizeof (dzp->z_id));
641 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_FLAGS(zfsvfs), NULL,
642 &zp->z_pflags, sizeof (zp->z_pflags));
643
644 if (!(flag & ZNEW)) {
645 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs), NULL,
646 ctime, sizeof (ctime));
647 zfs_tstamp_update_setup(zp, STATE_CHANGED, mtime,
648 ctime);
649 }
650 error = sa_bulk_update(zp->z_sa_hdl, bulk, count, tx);
651 ASSERT0(error);
652
653 dzp->z_size++;
654 dzp->z_links += zp_is_dir;
655 count = 0;
656 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_SIZE(zfsvfs), NULL,
657 &dzp->z_size, sizeof (dzp->z_size));
658 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_LINKS(zfsvfs), NULL,
659 &dzp->z_links, sizeof (dzp->z_links));
660 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MTIME(zfsvfs), NULL,
661 mtime, sizeof (mtime));
662 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs), NULL,
663 ctime, sizeof (ctime));
664 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_FLAGS(zfsvfs), NULL,
665 &dzp->z_pflags, sizeof (dzp->z_pflags));
666 zfs_tstamp_update_setup(dzp, CONTENT_MODIFIED, mtime, ctime);
667 error = sa_bulk_update(dzp->z_sa_hdl, bulk, count, tx);
668 ASSERT0(error);
669 return (0);
670 }
671
672 /*
673 * The match type in the code for this function should conform to:
674 *
675 * ------------------------------------------------------------------------
676 * fs type | z_norm | lookup type | match type
677 * ---------|-------------|-------------|----------------------------------
678 * CS !norm | 0 | 0 | 0 (exact)
679 * CS norm | formX | 0 | MT_NORMALIZE
680 * CI !norm | upper | !ZCIEXACT | MT_NORMALIZE
681 * CI !norm | upper | ZCIEXACT | MT_NORMALIZE | MT_MATCH_CASE
682 * CI norm | upper|formX | !ZCIEXACT | MT_NORMALIZE
683 * CI norm | upper|formX | ZCIEXACT | MT_NORMALIZE | MT_MATCH_CASE
684 * CM !norm | upper | !ZCILOOK | MT_NORMALIZE | MT_MATCH_CASE
685 * CM !norm | upper | ZCILOOK | MT_NORMALIZE
686 * CM norm | upper|formX | !ZCILOOK | MT_NORMALIZE | MT_MATCH_CASE
687 * CM norm | upper|formX | ZCILOOK | MT_NORMALIZE
688 *
689 * Abbreviations:
690 * CS = Case Sensitive, CI = Case Insensitive, CM = Case Mixed
691 * upper = case folding set by fs type on creation (U8_TEXTPREP_TOUPPER)
692 * formX = unicode normalization form set on fs creation
693 */
694 static int
zfs_dropname(znode_t * dzp,const char * name,znode_t * zp,dmu_tx_t * tx,int flag)695 zfs_dropname(znode_t *dzp, const char *name, znode_t *zp, dmu_tx_t *tx,
696 int flag)
697 {
698 int error;
699
700 if (zp->z_zfsvfs->z_norm) {
701 matchtype_t mt = MT_NORMALIZE;
702
703 if (zp->z_zfsvfs->z_case == ZFS_CASE_MIXED) {
704 mt |= MT_MATCH_CASE;
705 }
706
707 error = zap_remove_norm(zp->z_zfsvfs->z_os, dzp->z_id,
708 name, mt, tx);
709 } else {
710 error = zap_remove(zp->z_zfsvfs->z_os, dzp->z_id, name, tx);
711 }
712
713 return (error);
714 }
715
716 /*
717 * Unlink zp from dzp, and mark zp for deletion if this was the last link.
718 * Can fail if zp is a mount point (EBUSY) or a non-empty directory (EEXIST).
719 * If 'unlinkedp' is NULL, we put unlinked znodes on the unlinked list.
720 * If it's non-NULL, we use it to indicate whether the znode needs deletion,
721 * and it's the caller's job to do it.
722 */
723 int
zfs_link_destroy(znode_t * dzp,const char * name,znode_t * zp,dmu_tx_t * tx,int flag,boolean_t * unlinkedp)724 zfs_link_destroy(znode_t *dzp, const char *name, znode_t *zp, dmu_tx_t *tx,
725 int flag, boolean_t *unlinkedp)
726 {
727 zfsvfs_t *zfsvfs = dzp->z_zfsvfs;
728 vnode_t *vp = ZTOV(zp);
729 int zp_is_dir = (vp->v_type == VDIR);
730 boolean_t unlinked = B_FALSE;
731 sa_bulk_attr_t bulk[5];
732 uint64_t mtime[2], ctime[2];
733 int count = 0;
734 int error;
735
736 if (zfsvfs->z_replay == B_FALSE) {
737 ASSERT_VOP_ELOCKED(ZTOV(dzp), __func__);
738 ASSERT_VOP_ELOCKED(ZTOV(zp), __func__);
739 }
740 if (!(flag & ZRENAMING)) {
741
742 if (zp_is_dir && !zfs_dirempty(zp))
743 return (SET_ERROR(ENOTEMPTY));
744
745 /*
746 * If we get here, we are going to try to remove the object.
747 * First try removing the name from the directory; if that
748 * fails, return the error.
749 */
750 error = zfs_dropname(dzp, name, zp, tx, flag);
751 if (error != 0) {
752 return (error);
753 }
754
755 if (zp->z_links <= zp_is_dir) {
756 zfs_panic_recover("zfs: link count on vnode %p is %u, "
757 "should be at least %u", zp->z_vnode,
758 (int)zp->z_links,
759 zp_is_dir + 1);
760 zp->z_links = zp_is_dir + 1;
761 }
762 if (--zp->z_links == zp_is_dir) {
763 zp->z_unlinked = B_TRUE;
764 zp->z_links = 0;
765 unlinked = B_TRUE;
766 } else {
767 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs),
768 NULL, &ctime, sizeof (ctime));
769 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_FLAGS(zfsvfs),
770 NULL, &zp->z_pflags, sizeof (zp->z_pflags));
771 zfs_tstamp_update_setup(zp, STATE_CHANGED, mtime,
772 ctime);
773 }
774 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_LINKS(zfsvfs),
775 NULL, &zp->z_links, sizeof (zp->z_links));
776 error = sa_bulk_update(zp->z_sa_hdl, bulk, count, tx);
777 count = 0;
778 ASSERT0(error);
779 } else {
780 ASSERT(!zp->z_unlinked);
781 error = zfs_dropname(dzp, name, zp, tx, flag);
782 if (error != 0)
783 return (error);
784 }
785
786 dzp->z_size--; /* one dirent removed */
787 dzp->z_links -= zp_is_dir; /* ".." link from zp */
788 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_LINKS(zfsvfs),
789 NULL, &dzp->z_links, sizeof (dzp->z_links));
790 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_SIZE(zfsvfs),
791 NULL, &dzp->z_size, sizeof (dzp->z_size));
792 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs),
793 NULL, ctime, sizeof (ctime));
794 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MTIME(zfsvfs),
795 NULL, mtime, sizeof (mtime));
796 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_FLAGS(zfsvfs),
797 NULL, &dzp->z_pflags, sizeof (dzp->z_pflags));
798 zfs_tstamp_update_setup(dzp, CONTENT_MODIFIED, mtime, ctime);
799 error = sa_bulk_update(dzp->z_sa_hdl, bulk, count, tx);
800 ASSERT0(error);
801
802 if (unlinkedp != NULL)
803 *unlinkedp = unlinked;
804 else if (unlinked)
805 zfs_unlinked_add(zp, tx);
806
807 return (0);
808 }
809
810 /*
811 * Indicate whether the directory is empty.
812 */
813 boolean_t
zfs_dirempty(znode_t * dzp)814 zfs_dirempty(znode_t *dzp)
815 {
816 return (dzp->z_size == 2);
817 }
818
819 int
zfs_make_xattrdir(znode_t * zp,vattr_t * vap,znode_t ** xvpp,cred_t * cr)820 zfs_make_xattrdir(znode_t *zp, vattr_t *vap, znode_t **xvpp, cred_t *cr)
821 {
822 zfsvfs_t *zfsvfs = zp->z_zfsvfs;
823 znode_t *xzp;
824 dmu_tx_t *tx;
825 int error;
826 zfs_acl_ids_t acl_ids;
827 boolean_t fuid_dirtied;
828 uint64_t parent __maybe_unused;
829
830 *xvpp = NULL;
831
832 if ((error = zfs_acl_ids_create(zp, IS_XATTR, vap, cr, NULL,
833 &acl_ids, NULL)) != 0)
834 return (error);
835 if (zfs_acl_ids_overquota(zfsvfs, &acl_ids, 0)) {
836 zfs_acl_ids_free(&acl_ids);
837 return (SET_ERROR(EDQUOT));
838 }
839
840 getnewvnode_reserve();
841
842 tx = dmu_tx_create(zfsvfs->z_os);
843 dmu_tx_hold_sa_create(tx, acl_ids.z_aclp->z_acl_bytes +
844 ZFS_SA_BASE_ATTR_SIZE);
845 dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_TRUE);
846 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, FALSE, NULL);
847 fuid_dirtied = zfsvfs->z_fuid_dirty;
848 if (fuid_dirtied)
849 zfs_fuid_txhold(zfsvfs, tx);
850 error = dmu_tx_assign(tx, TXG_WAIT);
851 if (error) {
852 zfs_acl_ids_free(&acl_ids);
853 dmu_tx_abort(tx);
854 getnewvnode_drop_reserve();
855 return (error);
856 }
857 zfs_mknode(zp, vap, tx, cr, IS_XATTR, &xzp, &acl_ids);
858
859 if (fuid_dirtied)
860 zfs_fuid_sync(zfsvfs, tx);
861
862 ASSERT0(sa_lookup(xzp->z_sa_hdl, SA_ZPL_PARENT(zfsvfs), &parent,
863 sizeof (parent)));
864 ASSERT3U(parent, ==, zp->z_id);
865
866 VERIFY0(sa_update(zp->z_sa_hdl, SA_ZPL_XATTR(zfsvfs), &xzp->z_id,
867 sizeof (xzp->z_id), tx));
868
869 zfs_log_create(zfsvfs->z_log, tx, TX_MKXATTR, zp, xzp, "", NULL,
870 acl_ids.z_fuidp, vap);
871
872 zfs_acl_ids_free(&acl_ids);
873 dmu_tx_commit(tx);
874
875 getnewvnode_drop_reserve();
876
877 *xvpp = xzp;
878
879 return (0);
880 }
881
882 /*
883 * Return a znode for the extended attribute directory for zp.
884 * ** If the directory does not already exist, it is created **
885 *
886 * IN: zp - znode to obtain attribute directory from
887 * cr - credentials of caller
888 * flags - flags from the VOP_LOOKUP call
889 *
890 * OUT: xzpp - pointer to extended attribute znode
891 *
892 * RETURN: 0 on success
893 * error number on failure
894 */
895 int
zfs_get_xattrdir(znode_t * zp,znode_t ** xzpp,cred_t * cr,int flags)896 zfs_get_xattrdir(znode_t *zp, znode_t **xzpp, cred_t *cr, int flags)
897 {
898 zfsvfs_t *zfsvfs = zp->z_zfsvfs;
899 znode_t *xzp;
900 vattr_t va;
901 int error;
902 top:
903 error = zfs_dirent_lookup(zp, "", &xzp, ZXATTR);
904 if (error)
905 return (error);
906
907 if (xzp != NULL) {
908 *xzpp = xzp;
909 return (0);
910 }
911
912
913 if (!(flags & CREATE_XATTR_DIR))
914 return (SET_ERROR(ENOATTR));
915
916 if (zfsvfs->z_vfs->vfs_flag & VFS_RDONLY) {
917 return (SET_ERROR(EROFS));
918 }
919
920 /*
921 * The ability to 'create' files in an attribute
922 * directory comes from the write_xattr permission on the base file.
923 *
924 * The ability to 'search' an attribute directory requires
925 * read_xattr permission on the base file.
926 *
927 * Once in a directory the ability to read/write attributes
928 * is controlled by the permissions on the attribute file.
929 */
930 va.va_mask = AT_MODE | AT_UID | AT_GID;
931 va.va_type = VDIR;
932 va.va_mode = S_IFDIR | S_ISVTX | 0777;
933 zfs_fuid_map_ids(zp, cr, &va.va_uid, &va.va_gid);
934
935 error = zfs_make_xattrdir(zp, &va, xzpp, cr);
936
937 if (error == ERESTART) {
938 /* NB: we already did dmu_tx_wait() if necessary */
939 goto top;
940 }
941 if (error == 0)
942 VOP_UNLOCK(ZTOV(*xzpp));
943
944 return (error);
945 }
946
947 /*
948 * Decide whether it is okay to remove within a sticky directory.
949 *
950 * In sticky directories, write access is not sufficient;
951 * you can remove entries from a directory only if:
952 *
953 * you own the directory,
954 * you own the entry,
955 * the entry is a plain file and you have write access,
956 * or you are privileged (checked in secpolicy...).
957 *
958 * The function returns 0 if remove access is granted.
959 */
960 int
zfs_sticky_remove_access(znode_t * zdp,znode_t * zp,cred_t * cr)961 zfs_sticky_remove_access(znode_t *zdp, znode_t *zp, cred_t *cr)
962 {
963 uid_t uid;
964 uid_t downer;
965 uid_t fowner;
966 zfsvfs_t *zfsvfs = zdp->z_zfsvfs;
967
968 if (zdp->z_zfsvfs->z_replay)
969 return (0);
970
971 if ((zdp->z_mode & S_ISVTX) == 0)
972 return (0);
973
974 downer = zfs_fuid_map_id(zfsvfs, zdp->z_uid, cr, ZFS_OWNER);
975 fowner = zfs_fuid_map_id(zfsvfs, zp->z_uid, cr, ZFS_OWNER);
976
977 if ((uid = crgetuid(cr)) == downer || uid == fowner ||
978 (ZTOV(zp)->v_type == VREG &&
979 zfs_zaccess(zp, ACE_WRITE_DATA, 0, B_FALSE, cr, NULL) == 0))
980 return (0);
981 else
982 return (secpolicy_vnode_remove(ZTOV(zp), cr));
983 }
984