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 http://www.opensolaris.org/os/licensing.
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 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright (c) 2012, 2016 by Delphix. All rights reserved.
24 * Copyright (c) 2013 Martin Matuska. All rights reserved.
25 * Copyright (c) 2014 Joyent, Inc. All rights reserved.
26 * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
27 * Copyright 2015 Nexenta Systems, Inc. All rights reserved.
28 */
29
30 #include <sys/dmu.h>
31 #include <sys/dmu_objset.h>
32 #include <sys/dmu_tx.h>
33 #include <sys/dsl_dataset.h>
34 #include <sys/dsl_dir.h>
35 #include <sys/dsl_prop.h>
36 #include <sys/dsl_synctask.h>
37 #include <sys/dsl_deleg.h>
38 #include <sys/dmu_impl.h>
39 #include <sys/spa.h>
40 #include <sys/metaslab.h>
41 #include <sys/zap.h>
42 #include <sys/zio.h>
43 #include <sys/arc.h>
44 #include <sys/sunddi.h>
45 #include <sys/zfeature.h>
46 #include <sys/policy.h>
47 #include <sys/zfs_znode.h>
48 #include "zfs_namecheck.h"
49 #include "zfs_prop.h"
50
51 /*
52 * Filesystem and Snapshot Limits
53 * ------------------------------
54 *
55 * These limits are used to restrict the number of filesystems and/or snapshots
56 * that can be created at a given level in the tree or below. A typical
57 * use-case is with a delegated dataset where the administrator wants to ensure
58 * that a user within the zone is not creating too many additional filesystems
59 * or snapshots, even though they're not exceeding their space quota.
60 *
61 * The filesystem and snapshot counts are stored as extensible properties. This
62 * capability is controlled by a feature flag and must be enabled to be used.
63 * Once enabled, the feature is not active until the first limit is set. At
64 * that point, future operations to create/destroy filesystems or snapshots
65 * will validate and update the counts.
66 *
67 * Because the count properties will not exist before the feature is active,
68 * the counts are updated when a limit is first set on an uninitialized
69 * dsl_dir node in the tree (The filesystem/snapshot count on a node includes
70 * all of the nested filesystems/snapshots. Thus, a new leaf node has a
71 * filesystem count of 0 and a snapshot count of 0. Non-existent filesystem and
72 * snapshot count properties on a node indicate uninitialized counts on that
73 * node.) When first setting a limit on an uninitialized node, the code starts
74 * at the filesystem with the new limit and descends into all sub-filesystems
75 * to add the count properties.
76 *
77 * In practice this is lightweight since a limit is typically set when the
78 * filesystem is created and thus has no children. Once valid, changing the
79 * limit value won't require a re-traversal since the counts are already valid.
80 * When recursively fixing the counts, if a node with a limit is encountered
81 * during the descent, the counts are known to be valid and there is no need to
82 * descend into that filesystem's children. The counts on filesystems above the
83 * one with the new limit will still be uninitialized, unless a limit is
84 * eventually set on one of those filesystems. The counts are always recursively
85 * updated when a limit is set on a dataset, unless there is already a limit.
86 * When a new limit value is set on a filesystem with an existing limit, it is
87 * possible for the new limit to be less than the current count at that level
88 * since a user who can change the limit is also allowed to exceed the limit.
89 *
90 * Once the feature is active, then whenever a filesystem or snapshot is
91 * created, the code recurses up the tree, validating the new count against the
92 * limit at each initialized level. In practice, most levels will not have a
93 * limit set. If there is a limit at any initialized level up the tree, the
94 * check must pass or the creation will fail. Likewise, when a filesystem or
95 * snapshot is destroyed, the counts are recursively adjusted all the way up
96 * the initizized nodes in the tree. Renaming a filesystem into different point
97 * in the tree will first validate, then update the counts on each branch up to
98 * the common ancestor. A receive will also validate the counts and then update
99 * them.
100 *
101 * An exception to the above behavior is that the limit is not enforced if the
102 * user has permission to modify the limit. This is primarily so that
103 * recursive snapshots in the global zone always work. We want to prevent a
104 * denial-of-service in which a lower level delegated dataset could max out its
105 * limit and thus block recursive snapshots from being taken in the global zone.
106 * Because of this, it is possible for the snapshot count to be over the limit
107 * and snapshots taken in the global zone could cause a lower level dataset to
108 * hit or exceed its limit. The administrator taking the global zone recursive
109 * snapshot should be aware of this side-effect and behave accordingly.
110 * For consistency, the filesystem limit is also not enforced if the user can
111 * modify the limit.
112 *
113 * The filesystem and snapshot limits are validated by dsl_fs_ss_limit_check()
114 * and updated by dsl_fs_ss_count_adjust(). A new limit value is setup in
115 * dsl_dir_activate_fs_ss_limit() and the counts are adjusted, if necessary, by
116 * dsl_dir_init_fs_ss_count().
117 *
118 * There is a special case when we receive a filesystem that already exists. In
119 * this case a temporary clone name of %X is created (see dmu_recv_begin). We
120 * never update the filesystem counts for temporary clones.
121 *
122 * Likewise, we do not update the snapshot counts for temporary snapshots,
123 * such as those created by zfs diff.
124 */
125
126 extern inline dsl_dir_phys_t *dsl_dir_phys(dsl_dir_t *dd);
127
128 static uint64_t dsl_dir_space_towrite(dsl_dir_t *dd);
129
130 typedef struct ddulrt_arg {
131 dsl_dir_t *ddulrta_dd;
132 uint64_t ddlrta_txg;
133 } ddulrt_arg_t;
134
135 static void
136 dsl_dir_evict_async(void *dbu)
137 {
138 dsl_dir_t *dd = dbu;
139 dsl_pool_t *dp = dd->dd_pool;
140 int t;
141
142 dd->dd_dbuf = NULL;
143
144 for (t = 0; t < TXG_SIZE; t++) {
145 ASSERT(!txg_list_member(&dp->dp_dirty_dirs, dd, t));
146 ASSERT(dd->dd_tempreserved[t] == 0);
147 ASSERT(dd->dd_space_towrite[t] == 0);
148 }
149
150 if (dd->dd_parent)
151 dsl_dir_async_rele(dd->dd_parent, dd);
152
153 spa_async_close(dd->dd_pool->dp_spa, dd);
154
155 dsl_prop_fini(dd);
156 mutex_destroy(&dd->dd_lock);
157 kmem_free(dd, sizeof (dsl_dir_t));
158 }
159
160 int
161 dsl_dir_hold_obj(dsl_pool_t *dp, uint64_t ddobj,
162 const char *tail, void *tag, dsl_dir_t **ddp)
163 {
164 dmu_buf_t *dbuf;
165 dsl_dir_t *dd;
166 int err;
167
168 ASSERT(dsl_pool_config_held(dp));
169
170 err = dmu_bonus_hold(dp->dp_meta_objset, ddobj, tag, &dbuf);
171 if (err != 0)
172 return (err);
173 dd = dmu_buf_get_user(dbuf);
174 #ifdef ZFS_DEBUG
175 {
176 dmu_object_info_t doi;
177 dmu_object_info_from_db(dbuf, &doi);
178 ASSERT3U(doi.doi_bonus_type, ==, DMU_OT_DSL_DIR);
179 ASSERT3U(doi.doi_bonus_size, >=, sizeof (dsl_dir_phys_t));
180 }
181 #endif
182 if (dd == NULL) {
183 dsl_dir_t *winner;
184
185 dd = kmem_zalloc(sizeof (dsl_dir_t), KM_SLEEP);
186 dd->dd_object = ddobj;
187 dd->dd_dbuf = dbuf;
188 dd->dd_pool = dp;
189 mutex_init(&dd->dd_lock, NULL, MUTEX_DEFAULT, NULL);
190 dsl_prop_init(dd);
191
192 dsl_dir_snap_cmtime_update(dd);
193
194 if (dsl_dir_phys(dd)->dd_parent_obj) {
195 err = dsl_dir_hold_obj(dp,
196 dsl_dir_phys(dd)->dd_parent_obj, NULL, dd,
197 &dd->dd_parent);
198 if (err != 0)
199 goto errout;
200 if (tail) {
201 #ifdef ZFS_DEBUG
202 uint64_t foundobj;
203
204 err = zap_lookup(dp->dp_meta_objset,
205 dsl_dir_phys(dd->dd_parent)->
206 dd_child_dir_zapobj, tail,
207 sizeof (foundobj), 1, &foundobj);
208 ASSERT(err || foundobj == ddobj);
209 #endif
210 (void) strcpy(dd->dd_myname, tail);
211 } else {
212 err = zap_value_search(dp->dp_meta_objset,
213 dsl_dir_phys(dd->dd_parent)->
214 dd_child_dir_zapobj,
215 ddobj, 0, dd->dd_myname);
216 }
217 if (err != 0)
218 goto errout;
219 } else {
220 (void) strcpy(dd->dd_myname, spa_name(dp->dp_spa));
221 }
222
223 if (dsl_dir_is_clone(dd)) {
224 dmu_buf_t *origin_bonus;
225 dsl_dataset_phys_t *origin_phys;
226
227 /*
228 * We can't open the origin dataset, because
229 * that would require opening this dsl_dir.
230 * Just look at its phys directly instead.
231 */
232 err = dmu_bonus_hold(dp->dp_meta_objset,
233 dsl_dir_phys(dd)->dd_origin_obj, FTAG,
234 &origin_bonus);
235 if (err != 0)
236 goto errout;
237 origin_phys = origin_bonus->db_data;
238 dd->dd_origin_txg =
239 origin_phys->ds_creation_txg;
240 dmu_buf_rele(origin_bonus, FTAG);
241 }
242
243 dmu_buf_init_user(&dd->dd_dbu, NULL, dsl_dir_evict_async,
244 &dd->dd_dbuf);
245 winner = dmu_buf_set_user_ie(dbuf, &dd->dd_dbu);
246 if (winner != NULL) {
247 if (dd->dd_parent)
248 dsl_dir_rele(dd->dd_parent, dd);
249 dsl_prop_fini(dd);
250 mutex_destroy(&dd->dd_lock);
251 kmem_free(dd, sizeof (dsl_dir_t));
252 dd = winner;
253 } else {
254 spa_open_ref(dp->dp_spa, dd);
255 }
256 }
257
258 /*
259 * The dsl_dir_t has both open-to-close and instantiate-to-evict
260 * holds on the spa. We need the open-to-close holds because
261 * otherwise the spa_refcnt wouldn't change when we open a
262 * dir which the spa also has open, so we could incorrectly
263 * think it was OK to unload/export/destroy the pool. We need
264 * the instantiate-to-evict hold because the dsl_dir_t has a
265 * pointer to the dd_pool, which has a pointer to the spa_t.
266 */
267 spa_open_ref(dp->dp_spa, tag);
268 ASSERT3P(dd->dd_pool, ==, dp);
269 ASSERT3U(dd->dd_object, ==, ddobj);
270 ASSERT3P(dd->dd_dbuf, ==, dbuf);
271 *ddp = dd;
272 return (0);
273
274 errout:
275 if (dd->dd_parent)
276 dsl_dir_rele(dd->dd_parent, dd);
277 dsl_prop_fini(dd);
278 mutex_destroy(&dd->dd_lock);
279 kmem_free(dd, sizeof (dsl_dir_t));
280 dmu_buf_rele(dbuf, tag);
281 return (err);
282 }
283
284 void
285 dsl_dir_rele(dsl_dir_t *dd, void *tag)
286 {
287 dprintf_dd(dd, "%s\n", "");
288 spa_close(dd->dd_pool->dp_spa, tag);
289 dmu_buf_rele(dd->dd_dbuf, tag);
290 }
291
292 /*
293 * Remove a reference to the given dsl dir that is being asynchronously
294 * released. Async releases occur from a taskq performing eviction of
295 * dsl datasets and dirs. This process is identical to a normal release
296 * with the exception of using the async API for releasing the reference on
297 * the spa.
298 */
299 void
300 dsl_dir_async_rele(dsl_dir_t *dd, void *tag)
301 {
302 dprintf_dd(dd, "%s\n", "");
303 spa_async_close(dd->dd_pool->dp_spa, tag);
304 dmu_buf_rele(dd->dd_dbuf, tag);
305 }
306
307 /* buf must be at least ZFS_MAX_DATASET_NAME_LEN bytes */
308 void
309 dsl_dir_name(dsl_dir_t *dd, char *buf)
310 {
311 if (dd->dd_parent) {
312 dsl_dir_name(dd->dd_parent, buf);
313 VERIFY3U(strlcat(buf, "/", ZFS_MAX_DATASET_NAME_LEN), <,
314 ZFS_MAX_DATASET_NAME_LEN);
315 } else {
316 buf[0] = '\0';
317 }
318 if (!MUTEX_HELD(&dd->dd_lock)) {
319 /*
320 * recursive mutex so that we can use
321 * dprintf_dd() with dd_lock held
322 */
323 mutex_enter(&dd->dd_lock);
324 VERIFY3U(strlcat(buf, dd->dd_myname, ZFS_MAX_DATASET_NAME_LEN),
325 <, ZFS_MAX_DATASET_NAME_LEN);
326 mutex_exit(&dd->dd_lock);
327 } else {
328 VERIFY3U(strlcat(buf, dd->dd_myname, ZFS_MAX_DATASET_NAME_LEN),
329 <, ZFS_MAX_DATASET_NAME_LEN);
330 }
331 }
332
333 /* Calculate name length, avoiding all the strcat calls of dsl_dir_name */
334 int
335 dsl_dir_namelen(dsl_dir_t *dd)
336 {
337 int result = 0;
338
339 if (dd->dd_parent) {
340 /* parent's name + 1 for the "/" */
341 result = dsl_dir_namelen(dd->dd_parent) + 1;
342 }
343
344 if (!MUTEX_HELD(&dd->dd_lock)) {
345 /* see dsl_dir_name */
346 mutex_enter(&dd->dd_lock);
347 result += strlen(dd->dd_myname);
348 mutex_exit(&dd->dd_lock);
349 } else {
350 result += strlen(dd->dd_myname);
351 }
352
353 return (result);
354 }
355
356 static int
357 getcomponent(const char *path, char *component, const char **nextp)
358 {
359 char *p;
360
361 if ((path == NULL) || (path[0] == '\0'))
362 return (SET_ERROR(ENOENT));
363 /* This would be a good place to reserve some namespace... */
364 p = strpbrk(path, "/@");
365 if (p && (p[1] == '/' || p[1] == '@')) {
366 /* two separators in a row */
367 return (SET_ERROR(EINVAL));
368 }
369 if (p == NULL || p == path) {
370 /*
371 * if the first thing is an @ or /, it had better be an
372 * @ and it had better not have any more ats or slashes,
373 * and it had better have something after the @.
374 */
375 if (p != NULL &&
376 (p[0] != '@' || strpbrk(path+1, "/@") || p[1] == '\0'))
377 return (SET_ERROR(EINVAL));
378 if (strlen(path) >= ZFS_MAX_DATASET_NAME_LEN)
379 return (SET_ERROR(ENAMETOOLONG));
380 (void) strcpy(component, path);
381 p = NULL;
382 } else if (p[0] == '/') {
383 if (p - path >= ZFS_MAX_DATASET_NAME_LEN)
384 return (SET_ERROR(ENAMETOOLONG));
385 (void) strncpy(component, path, p - path);
386 component[p - path] = '\0';
387 p++;
388 } else if (p[0] == '@') {
389 /*
390 * if the next separator is an @, there better not be
391 * any more slashes.
392 */
393 if (strchr(path, '/'))
394 return (SET_ERROR(EINVAL));
395 if (p - path >= ZFS_MAX_DATASET_NAME_LEN)
396 return (SET_ERROR(ENAMETOOLONG));
397 (void) strncpy(component, path, p - path);
398 component[p - path] = '\0';
399 } else {
400 panic("invalid p=%p", (void *)p);
401 }
402 *nextp = p;
403 return (0);
404 }
405
406 /*
407 * Return the dsl_dir_t, and possibly the last component which couldn't
408 * be found in *tail. The name must be in the specified dsl_pool_t. This
409 * thread must hold the dp_config_rwlock for the pool. Returns NULL if the
410 * path is bogus, or if tail==NULL and we couldn't parse the whole name.
411 * (*tail)[0] == '@' means that the last component is a snapshot.
412 */
413 int
414 dsl_dir_hold(dsl_pool_t *dp, const char *name, void *tag,
415 dsl_dir_t **ddp, const char **tailp)
416 {
417 char buf[ZFS_MAX_DATASET_NAME_LEN];
418 const char *spaname, *next, *nextnext = NULL;
419 int err;
420 dsl_dir_t *dd;
421 uint64_t ddobj;
422
423 err = getcomponent(name, buf, &next);
424 if (err != 0)
425 return (err);
426
427 /* Make sure the name is in the specified pool. */
428 spaname = spa_name(dp->dp_spa);
429 if (strcmp(buf, spaname) != 0)
430 return (SET_ERROR(EXDEV));
431
432 ASSERT(dsl_pool_config_held(dp));
433
434 err = dsl_dir_hold_obj(dp, dp->dp_root_dir_obj, NULL, tag, &dd);
435 if (err != 0) {
436 return (err);
437 }
438
439 while (next != NULL) {
440 dsl_dir_t *child_dd;
441 err = getcomponent(next, buf, &nextnext);
442 if (err != 0)
443 break;
444 ASSERT(next[0] != '\0');
445 if (next[0] == '@')
446 break;
447 dprintf("looking up %s in obj%lld\n",
448 buf, dsl_dir_phys(dd)->dd_child_dir_zapobj);
449
450 err = zap_lookup(dp->dp_meta_objset,
451 dsl_dir_phys(dd)->dd_child_dir_zapobj,
452 buf, sizeof (ddobj), 1, &ddobj);
453 if (err != 0) {
454 if (err == ENOENT)
455 err = 0;
456 break;
457 }
458
459 err = dsl_dir_hold_obj(dp, ddobj, buf, tag, &child_dd);
460 if (err != 0)
461 break;
462 dsl_dir_rele(dd, tag);
463 dd = child_dd;
464 next = nextnext;
465 }
466
467 if (err != 0) {
468 dsl_dir_rele(dd, tag);
469 return (err);
470 }
471
472 /*
473 * It's an error if there's more than one component left, or
474 * tailp==NULL and there's any component left.
475 */
476 if (next != NULL &&
477 (tailp == NULL || (nextnext && nextnext[0] != '\0'))) {
478 /* bad path name */
479 dsl_dir_rele(dd, tag);
480 dprintf("next=%p (%s) tail=%p\n", next, next?next:"", tailp);
481 err = SET_ERROR(ENOENT);
482 }
483 if (tailp != NULL)
484 *tailp = next;
485 *ddp = dd;
486 return (err);
487 }
488
489 /*
490 * If the counts are already initialized for this filesystem and its
491 * descendants then do nothing, otherwise initialize the counts.
492 *
493 * The counts on this filesystem, and those below, may be uninitialized due to
494 * either the use of a pre-existing pool which did not support the
495 * filesystem/snapshot limit feature, or one in which the feature had not yet
496 * been enabled.
497 *
498 * Recursively descend the filesystem tree and update the filesystem/snapshot
499 * counts on each filesystem below, then update the cumulative count on the
500 * current filesystem. If the filesystem already has a count set on it,
501 * then we know that its counts, and the counts on the filesystems below it,
502 * are already correct, so we don't have to update this filesystem.
503 */
504 static void
505 dsl_dir_init_fs_ss_count(dsl_dir_t *dd, dmu_tx_t *tx)
506 {
507 uint64_t my_fs_cnt = 0;
508 uint64_t my_ss_cnt = 0;
509 dsl_pool_t *dp = dd->dd_pool;
510 objset_t *os = dp->dp_meta_objset;
511 zap_cursor_t *zc;
512 zap_attribute_t *za;
513 dsl_dataset_t *ds;
514
515 ASSERT(spa_feature_is_active(dp->dp_spa, SPA_FEATURE_FS_SS_LIMIT));
516 ASSERT(dsl_pool_config_held(dp));
517 ASSERT(dmu_tx_is_syncing(tx));
518
519 dsl_dir_zapify(dd, tx);
520
521 /*
522 * If the filesystem count has already been initialized then we
523 * don't need to recurse down any further.
524 */
525 if (zap_contains(os, dd->dd_object, DD_FIELD_FILESYSTEM_COUNT) == 0)
526 return;
527
528 zc = kmem_alloc(sizeof (zap_cursor_t), KM_SLEEP);
529 za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
530
531 /* Iterate my child dirs */
532 for (zap_cursor_init(zc, os, dsl_dir_phys(dd)->dd_child_dir_zapobj);
533 zap_cursor_retrieve(zc, za) == 0; zap_cursor_advance(zc)) {
534 dsl_dir_t *chld_dd;
535 uint64_t count;
536
537 VERIFY0(dsl_dir_hold_obj(dp, za->za_first_integer, NULL, FTAG,
538 &chld_dd));
539
540 /*
541 * Ignore hidden ($FREE, $MOS & $ORIGIN) objsets and
542 * temporary datasets.
543 */
544 if (chld_dd->dd_myname[0] == '$' ||
545 chld_dd->dd_myname[0] == '%') {
546 dsl_dir_rele(chld_dd, FTAG);
547 continue;
548 }
549
550 my_fs_cnt++; /* count this child */
551
552 dsl_dir_init_fs_ss_count(chld_dd, tx);
553
554 VERIFY0(zap_lookup(os, chld_dd->dd_object,
555 DD_FIELD_FILESYSTEM_COUNT, sizeof (count), 1, &count));
556 my_fs_cnt += count;
557 VERIFY0(zap_lookup(os, chld_dd->dd_object,
558 DD_FIELD_SNAPSHOT_COUNT, sizeof (count), 1, &count));
559 my_ss_cnt += count;
560
561 dsl_dir_rele(chld_dd, FTAG);
562 }
563 zap_cursor_fini(zc);
564 /* Count my snapshots (we counted children's snapshots above) */
565 VERIFY0(dsl_dataset_hold_obj(dd->dd_pool,
566 dsl_dir_phys(dd)->dd_head_dataset_obj, FTAG, &ds));
567
568 for (zap_cursor_init(zc, os, dsl_dataset_phys(ds)->ds_snapnames_zapobj);
569 zap_cursor_retrieve(zc, za) == 0;
570 zap_cursor_advance(zc)) {
571 /* Don't count temporary snapshots */
572 if (za->za_name[0] != '%')
573 my_ss_cnt++;
574 }
575 zap_cursor_fini(zc);
576
577 dsl_dataset_rele(ds, FTAG);
578
579 kmem_free(zc, sizeof (zap_cursor_t));
580 kmem_free(za, sizeof (zap_attribute_t));
581
582 /* we're in a sync task, update counts */
583 dmu_buf_will_dirty(dd->dd_dbuf, tx);
584 VERIFY0(zap_add(os, dd->dd_object, DD_FIELD_FILESYSTEM_COUNT,
585 sizeof (my_fs_cnt), 1, &my_fs_cnt, tx));
586 VERIFY0(zap_add(os, dd->dd_object, DD_FIELD_SNAPSHOT_COUNT,
587 sizeof (my_ss_cnt), 1, &my_ss_cnt, tx));
588 }
589
590 static int
591 dsl_dir_actv_fs_ss_limit_check(void *arg, dmu_tx_t *tx)
592 {
593 char *ddname = (char *)arg;
594 dsl_pool_t *dp = dmu_tx_pool(tx);
595 dsl_dataset_t *ds;
596 dsl_dir_t *dd;
597 int error;
598
599 error = dsl_dataset_hold(dp, ddname, FTAG, &ds);
600 if (error != 0)
601 return (error);
602
603 if (!spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_FS_SS_LIMIT)) {
604 dsl_dataset_rele(ds, FTAG);
605 return (SET_ERROR(ENOTSUP));
606 }
607
608 dd = ds->ds_dir;
609 if (spa_feature_is_active(dp->dp_spa, SPA_FEATURE_FS_SS_LIMIT) &&
610 dsl_dir_is_zapified(dd) &&
611 zap_contains(dp->dp_meta_objset, dd->dd_object,
612 DD_FIELD_FILESYSTEM_COUNT) == 0) {
613 dsl_dataset_rele(ds, FTAG);
614 return (SET_ERROR(EALREADY));
615 }
616
617 dsl_dataset_rele(ds, FTAG);
618 return (0);
619 }
620
621 static void
622 dsl_dir_actv_fs_ss_limit_sync(void *arg, dmu_tx_t *tx)
623 {
624 char *ddname = (char *)arg;
625 dsl_pool_t *dp = dmu_tx_pool(tx);
626 dsl_dataset_t *ds;
627 spa_t *spa;
628
629 VERIFY0(dsl_dataset_hold(dp, ddname, FTAG, &ds));
630
631 spa = dsl_dataset_get_spa(ds);
632
633 if (!spa_feature_is_active(spa, SPA_FEATURE_FS_SS_LIMIT)) {
634 /*
635 * Since the feature was not active and we're now setting a
636 * limit, increment the feature-active counter so that the
637 * feature becomes active for the first time.
638 *
639 * We are already in a sync task so we can update the MOS.
640 */
641 spa_feature_incr(spa, SPA_FEATURE_FS_SS_LIMIT, tx);
642 }
643
644 /*
645 * Since we are now setting a non-UINT64_MAX limit on the filesystem,
646 * we need to ensure the counts are correct. Descend down the tree from
647 * this point and update all of the counts to be accurate.
648 */
649 dsl_dir_init_fs_ss_count(ds->ds_dir, tx);
650
651 dsl_dataset_rele(ds, FTAG);
652 }
653
654 /*
655 * Make sure the feature is enabled and activate it if necessary.
656 * Since we're setting a limit, ensure the on-disk counts are valid.
657 * This is only called by the ioctl path when setting a limit value.
658 *
659 * We do not need to validate the new limit, since users who can change the
660 * limit are also allowed to exceed the limit.
661 */
662 int
663 dsl_dir_activate_fs_ss_limit(const char *ddname)
664 {
665 int error;
666
667 error = dsl_sync_task(ddname, dsl_dir_actv_fs_ss_limit_check,
668 dsl_dir_actv_fs_ss_limit_sync, (void *)ddname, 0,
669 ZFS_SPACE_CHECK_RESERVED);
670
671 if (error == EALREADY)
672 error = 0;
673
674 return (error);
675 }
676
677 /*
678 * Used to determine if the filesystem_limit or snapshot_limit should be
679 * enforced. We allow the limit to be exceeded if the user has permission to
680 * write the property value. We pass in the creds that we got in the open
681 * context since we will always be the GZ root in syncing context. We also have
682 * to handle the case where we are allowed to change the limit on the current
683 * dataset, but there may be another limit in the tree above.
684 *
685 * We can never modify these two properties within a non-global zone. In
686 * addition, the other checks are modeled on zfs_secpolicy_write_perms. We
687 * can't use that function since we are already holding the dp_config_rwlock.
688 * In addition, we already have the dd and dealing with snapshots is simplified
689 * in this code.
690 */
691
692 typedef enum {
693 ENFORCE_ALWAYS,
694 ENFORCE_NEVER,
695 ENFORCE_ABOVE
696 } enforce_res_t;
697
698 static enforce_res_t
699 dsl_enforce_ds_ss_limits(dsl_dir_t *dd, zfs_prop_t prop, cred_t *cr)
700 {
701 enforce_res_t enforce = ENFORCE_ALWAYS;
702 uint64_t obj;
703 dsl_dataset_t *ds;
704 uint64_t zoned;
705
706 ASSERT(prop == ZFS_PROP_FILESYSTEM_LIMIT ||
707 prop == ZFS_PROP_SNAPSHOT_LIMIT);
708
709 #ifdef _KERNEL
710 if (crgetzoneid(cr) != GLOBAL_ZONEID)
711 return (ENFORCE_ALWAYS);
712
713 if (secpolicy_zfs(cr) == 0)
714 return (ENFORCE_NEVER);
715 #endif
716
717 if ((obj = dsl_dir_phys(dd)->dd_head_dataset_obj) == 0)
718 return (ENFORCE_ALWAYS);
719
720 ASSERT(dsl_pool_config_held(dd->dd_pool));
721
722 if (dsl_dataset_hold_obj(dd->dd_pool, obj, FTAG, &ds) != 0)
723 return (ENFORCE_ALWAYS);
724
725 if (dsl_prop_get_ds(ds, "zoned", 8, 1, &zoned, NULL) || zoned) {
726 /* Only root can access zoned fs's from the GZ */
727 enforce = ENFORCE_ALWAYS;
728 } else {
729 if (dsl_deleg_access_impl(ds, zfs_prop_to_name(prop), cr) == 0)
730 enforce = ENFORCE_ABOVE;
731 }
732
733 dsl_dataset_rele(ds, FTAG);
734 return (enforce);
735 }
736
737 static void
738 dsl_dir_update_last_remap_txg_sync(void *varg, dmu_tx_t *tx)
739 {
740 ddulrt_arg_t *arg = varg;
741 uint64_t last_remap_txg;
742 dsl_dir_t *dd = arg->ddulrta_dd;
743 objset_t *mos = dd->dd_pool->dp_meta_objset;
744
745 dsl_dir_zapify(dd, tx);
746 if (zap_lookup(mos, dd->dd_object, DD_FIELD_LAST_REMAP_TXG,
747 sizeof (last_remap_txg), 1, &last_remap_txg) != 0 ||
748 last_remap_txg < arg->ddlrta_txg) {
749 VERIFY0(zap_update(mos, dd->dd_object, DD_FIELD_LAST_REMAP_TXG,
750 sizeof (arg->ddlrta_txg), 1, &arg->ddlrta_txg, tx));
751 }
752 }
753
754 int
755 dsl_dir_update_last_remap_txg(dsl_dir_t *dd, uint64_t txg)
756 {
757 ddulrt_arg_t arg;
758 arg.ddulrta_dd = dd;
759 arg.ddlrta_txg = txg;
760
761 return (dsl_sync_task(spa_name(dd->dd_pool->dp_spa),
762 NULL, dsl_dir_update_last_remap_txg_sync, &arg,
763 1, ZFS_SPACE_CHECK_RESERVED));
764 }
765
766 /*
767 * Check if adding additional child filesystem(s) would exceed any filesystem
768 * limits or adding additional snapshot(s) would exceed any snapshot limits.
769 * The prop argument indicates which limit to check.
770 *
771 * Note that all filesystem limits up to the root (or the highest
772 * initialized) filesystem or the given ancestor must be satisfied.
773 */
774 int
775 dsl_fs_ss_limit_check(dsl_dir_t *dd, uint64_t delta, zfs_prop_t prop,
776 dsl_dir_t *ancestor, cred_t *cr)
777 {
778 objset_t *os = dd->dd_pool->dp_meta_objset;
779 uint64_t limit, count;
780 char *count_prop;
781 enforce_res_t enforce;
782 int err = 0;
783
784 ASSERT(dsl_pool_config_held(dd->dd_pool));
785 ASSERT(prop == ZFS_PROP_FILESYSTEM_LIMIT ||
786 prop == ZFS_PROP_SNAPSHOT_LIMIT);
787
788 /*
789 * If we're allowed to change the limit, don't enforce the limit
790 * e.g. this can happen if a snapshot is taken by an administrative
791 * user in the global zone (i.e. a recursive snapshot by root).
792 * However, we must handle the case of delegated permissions where we
793 * are allowed to change the limit on the current dataset, but there
794 * is another limit in the tree above.
795 */
796 enforce = dsl_enforce_ds_ss_limits(dd, prop, cr);
797 if (enforce == ENFORCE_NEVER)
798 return (0);
799
800 /*
801 * e.g. if renaming a dataset with no snapshots, count adjustment
802 * is 0.
803 */
804 if (delta == 0)
805 return (0);
806
807 if (prop == ZFS_PROP_SNAPSHOT_LIMIT) {
808 /*
809 * We don't enforce the limit for temporary snapshots. This is
810 * indicated by a NULL cred_t argument.
811 */
812 if (cr == NULL)
813 return (0);
814
815 count_prop = DD_FIELD_SNAPSHOT_COUNT;
816 } else {
817 count_prop = DD_FIELD_FILESYSTEM_COUNT;
818 }
819
820 /*
821 * If an ancestor has been provided, stop checking the limit once we
822 * hit that dir. We need this during rename so that we don't overcount
823 * the check once we recurse up to the common ancestor.
824 */
825 if (ancestor == dd)
826 return (0);
827
828 /*
829 * If we hit an uninitialized node while recursing up the tree, we can
830 * stop since we know there is no limit here (or above). The counts are
831 * not valid on this node and we know we won't touch this node's counts.
832 */
833 if (!dsl_dir_is_zapified(dd) || zap_lookup(os, dd->dd_object,
834 count_prop, sizeof (count), 1, &count) == ENOENT)
835 return (0);
836
837 err = dsl_prop_get_dd(dd, zfs_prop_to_name(prop), 8, 1, &limit, NULL,
838 B_FALSE);
839 if (err != 0)
840 return (err);
841
842 /* Is there a limit which we've hit? */
843 if (enforce == ENFORCE_ALWAYS && (count + delta) > limit)
844 return (SET_ERROR(EDQUOT));
845
846 if (dd->dd_parent != NULL)
847 err = dsl_fs_ss_limit_check(dd->dd_parent, delta, prop,
848 ancestor, cr);
849
850 return (err);
851 }
852
853 /*
854 * Adjust the filesystem or snapshot count for the specified dsl_dir_t and all
855 * parents. When a new filesystem/snapshot is created, increment the count on
856 * all parents, and when a filesystem/snapshot is destroyed, decrement the
857 * count.
858 */
859 void
860 dsl_fs_ss_count_adjust(dsl_dir_t *dd, int64_t delta, const char *prop,
861 dmu_tx_t *tx)
862 {
863 int err;
864 objset_t *os = dd->dd_pool->dp_meta_objset;
865 uint64_t count;
866
867 ASSERT(dsl_pool_config_held(dd->dd_pool));
868 ASSERT(dmu_tx_is_syncing(tx));
869 ASSERT(strcmp(prop, DD_FIELD_FILESYSTEM_COUNT) == 0 ||
870 strcmp(prop, DD_FIELD_SNAPSHOT_COUNT) == 0);
871
872 /*
873 * When we receive an incremental stream into a filesystem that already
874 * exists, a temporary clone is created. We don't count this temporary
875 * clone, whose name begins with a '%'. We also ignore hidden ($FREE,
876 * $MOS & $ORIGIN) objsets.
877 */
878 if ((dd->dd_myname[0] == '%' || dd->dd_myname[0] == '$') &&
879 strcmp(prop, DD_FIELD_FILESYSTEM_COUNT) == 0)
880 return;
881
882 /*
883 * e.g. if renaming a dataset with no snapshots, count adjustment is 0
884 */
885 if (delta == 0)
886 return;
887
888 /*
889 * If we hit an uninitialized node while recursing up the tree, we can
890 * stop since we know the counts are not valid on this node and we
891 * know we shouldn't touch this node's counts. An uninitialized count
892 * on the node indicates that either the feature has not yet been
893 * activated or there are no limits on this part of the tree.
894 */
895 if (!dsl_dir_is_zapified(dd) || (err = zap_lookup(os, dd->dd_object,
896 prop, sizeof (count), 1, &count)) == ENOENT)
897 return;
898 VERIFY0(err);
899
900 count += delta;
901 /* Use a signed verify to make sure we're not neg. */
902 VERIFY3S(count, >=, 0);
903
904 VERIFY0(zap_update(os, dd->dd_object, prop, sizeof (count), 1, &count,
905 tx));
906
907 /* Roll up this additional count into our ancestors */
908 if (dd->dd_parent != NULL)
909 dsl_fs_ss_count_adjust(dd->dd_parent, delta, prop, tx);
910 }
911
912 uint64_t
913 dsl_dir_create_sync(dsl_pool_t *dp, dsl_dir_t *pds, const char *name,
914 dmu_tx_t *tx)
915 {
916 objset_t *mos = dp->dp_meta_objset;
917 uint64_t ddobj;
918 dsl_dir_phys_t *ddphys;
919 dmu_buf_t *dbuf;
920
921 ddobj = dmu_object_alloc(mos, DMU_OT_DSL_DIR, 0,
922 DMU_OT_DSL_DIR, sizeof (dsl_dir_phys_t), tx);
923 if (pds) {
924 VERIFY(0 == zap_add(mos, dsl_dir_phys(pds)->dd_child_dir_zapobj,
925 name, sizeof (uint64_t), 1, &ddobj, tx));
926 } else {
927 /* it's the root dir */
928 VERIFY(0 == zap_add(mos, DMU_POOL_DIRECTORY_OBJECT,
929 DMU_POOL_ROOT_DATASET, sizeof (uint64_t), 1, &ddobj, tx));
930 }
931 VERIFY(0 == dmu_bonus_hold(mos, ddobj, FTAG, &dbuf));
932 dmu_buf_will_dirty(dbuf, tx);
933 ddphys = dbuf->db_data;
934
935 ddphys->dd_creation_time = gethrestime_sec();
936 if (pds) {
937 ddphys->dd_parent_obj = pds->dd_object;
938
939 /* update the filesystem counts */
940 dsl_fs_ss_count_adjust(pds, 1, DD_FIELD_FILESYSTEM_COUNT, tx);
941 }
942 ddphys->dd_props_zapobj = zap_create(mos,
943 DMU_OT_DSL_PROPS, DMU_OT_NONE, 0, tx);
944 ddphys->dd_child_dir_zapobj = zap_create(mos,
945 DMU_OT_DSL_DIR_CHILD_MAP, DMU_OT_NONE, 0, tx);
946 if (spa_version(dp->dp_spa) >= SPA_VERSION_USED_BREAKDOWN)
947 ddphys->dd_flags |= DD_FLAG_USED_BREAKDOWN;
948 dmu_buf_rele(dbuf, FTAG);
949
950 return (ddobj);
951 }
952
953 boolean_t
954 dsl_dir_is_clone(dsl_dir_t *dd)
955 {
956 return (dsl_dir_phys(dd)->dd_origin_obj &&
957 (dd->dd_pool->dp_origin_snap == NULL ||
958 dsl_dir_phys(dd)->dd_origin_obj !=
959 dd->dd_pool->dp_origin_snap->ds_object));
960 }
961
962
963 uint64_t
964 dsl_dir_get_used(dsl_dir_t *dd)
965 {
966 return (dsl_dir_phys(dd)->dd_used_bytes);
967 }
968
969 uint64_t
970 dsl_dir_get_quota(dsl_dir_t *dd)
971 {
972 return (dsl_dir_phys(dd)->dd_quota);
973 }
974
975 uint64_t
976 dsl_dir_get_reservation(dsl_dir_t *dd)
977 {
978 return (dsl_dir_phys(dd)->dd_reserved);
979 }
980
981 uint64_t
982 dsl_dir_get_compressratio(dsl_dir_t *dd)
983 {
984 /* a fixed point number, 100x the ratio */
985 return (dsl_dir_phys(dd)->dd_compressed_bytes == 0 ? 100 :
986 (dsl_dir_phys(dd)->dd_uncompressed_bytes * 100 /
987 dsl_dir_phys(dd)->dd_compressed_bytes));
988 }
989
990 uint64_t
991 dsl_dir_get_logicalused(dsl_dir_t *dd)
992 {
993 return (dsl_dir_phys(dd)->dd_uncompressed_bytes);
994 }
995
996 uint64_t
997 dsl_dir_get_usedsnap(dsl_dir_t *dd)
998 {
999 return (dsl_dir_phys(dd)->dd_used_breakdown[DD_USED_SNAP]);
1000 }
1001
1002 uint64_t
1003 dsl_dir_get_usedds(dsl_dir_t *dd)
1004 {
1005 return (dsl_dir_phys(dd)->dd_used_breakdown[DD_USED_HEAD]);
1006 }
1007
1008 uint64_t
1009 dsl_dir_get_usedrefreserv(dsl_dir_t *dd)
1010 {
1011 return (dsl_dir_phys(dd)->dd_used_breakdown[DD_USED_REFRSRV]);
1012 }
1013
1014 uint64_t
1015 dsl_dir_get_usedchild(dsl_dir_t *dd)
1016 {
1017 return (dsl_dir_phys(dd)->dd_used_breakdown[DD_USED_CHILD] +
1018 dsl_dir_phys(dd)->dd_used_breakdown[DD_USED_CHILD_RSRV]);
1019 }
1020
1021 void
1022 dsl_dir_get_origin(dsl_dir_t *dd, char *buf)
1023 {
1024 dsl_dataset_t *ds;
1025 VERIFY0(dsl_dataset_hold_obj(dd->dd_pool,
1026 dsl_dir_phys(dd)->dd_origin_obj, FTAG, &ds));
1027
1028 dsl_dataset_name(ds, buf);
1029
1030 dsl_dataset_rele(ds, FTAG);
1031 }
1032
1033 int
1034 dsl_dir_get_filesystem_count(dsl_dir_t *dd, uint64_t *count)
1035 {
1036 if (dsl_dir_is_zapified(dd)) {
1037 objset_t *os = dd->dd_pool->dp_meta_objset;
1038 return (zap_lookup(os, dd->dd_object, DD_FIELD_FILESYSTEM_COUNT,
1039 sizeof (*count), 1, count));
1040 } else {
1041 return (ENOENT);
1042 }
1043 }
1044
1045 int
1046 dsl_dir_get_snapshot_count(dsl_dir_t *dd, uint64_t *count)
1047 {
1048 if (dsl_dir_is_zapified(dd)) {
1049 objset_t *os = dd->dd_pool->dp_meta_objset;
1050 return (zap_lookup(os, dd->dd_object, DD_FIELD_SNAPSHOT_COUNT,
1051 sizeof (*count), 1, count));
1052 } else {
1053 return (ENOENT);
1054 }
1055 }
1056
1057 int
1058 dsl_dir_get_remaptxg(dsl_dir_t *dd, uint64_t *count)
1059 {
1060 if (dsl_dir_is_zapified(dd)) {
1061 objset_t *os = dd->dd_pool->dp_meta_objset;
1062 return (zap_lookup(os, dd->dd_object, DD_FIELD_LAST_REMAP_TXG,
1063 sizeof (*count), 1, count));
1064 } else {
1065 return (ENOENT);
1066 }
1067 }
1068
1069 void
1070 dsl_dir_stats(dsl_dir_t *dd, nvlist_t *nv)
1071 {
1072 mutex_enter(&dd->dd_lock);
1073 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_QUOTA,
1074 dsl_dir_get_quota(dd));
1075 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_RESERVATION,
1076 dsl_dir_get_reservation(dd));
1077 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_LOGICALUSED,
1078 dsl_dir_get_logicalused(dd));
1079 if (dsl_dir_phys(dd)->dd_flags & DD_FLAG_USED_BREAKDOWN) {
1080 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USEDSNAP,
1081 dsl_dir_get_usedsnap(dd));
1082 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USEDDS,
1083 dsl_dir_get_usedds(dd));
1084 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USEDREFRESERV,
1085 dsl_dir_get_usedrefreserv(dd));
1086 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USEDCHILD,
1087 dsl_dir_get_usedchild(dd));
1088 }
1089 mutex_exit(&dd->dd_lock);
1090
1091 uint64_t count;
1092 if (dsl_dir_get_filesystem_count(dd, &count) == 0) {
1093 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_FILESYSTEM_COUNT,
1094 count);
1095 }
1096 if (dsl_dir_get_snapshot_count(dd, &count) == 0) {
1097 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_SNAPSHOT_COUNT,
1098 count);
1099 }
1100 if (dsl_dir_get_remaptxg(dd, &count) == 0) {
1101 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REMAPTXG,
1102 count);
1103 }
1104
1105 if (dsl_dir_is_clone(dd)) {
1106 char buf[ZFS_MAX_DATASET_NAME_LEN];
1107 dsl_dir_get_origin(dd, buf);
1108 dsl_prop_nvlist_add_string(nv, ZFS_PROP_ORIGIN, buf);
1109 }
1110
1111 }
1112
1113 void
1114 dsl_dir_dirty(dsl_dir_t *dd, dmu_tx_t *tx)
1115 {
1116 dsl_pool_t *dp = dd->dd_pool;
1117
1118 ASSERT(dsl_dir_phys(dd));
1119
1120 if (txg_list_add(&dp->dp_dirty_dirs, dd, tx->tx_txg)) {
1121 /* up the hold count until we can be written out */
1122 dmu_buf_add_ref(dd->dd_dbuf, dd);
1123 }
1124 }
1125
1126 static int64_t
1127 parent_delta(dsl_dir_t *dd, uint64_t used, int64_t delta)
1128 {
1129 uint64_t old_accounted = MAX(used, dsl_dir_phys(dd)->dd_reserved);
1130 uint64_t new_accounted =
1131 MAX(used + delta, dsl_dir_phys(dd)->dd_reserved);
1132 return (new_accounted - old_accounted);
1133 }
1134
1135 void
1136 dsl_dir_sync(dsl_dir_t *dd, dmu_tx_t *tx)
1137 {
1138 ASSERT(dmu_tx_is_syncing(tx));
1139
1140 mutex_enter(&dd->dd_lock);
1141 ASSERT0(dd->dd_tempreserved[tx->tx_txg&TXG_MASK]);
1142 dprintf_dd(dd, "txg=%llu towrite=%lluK\n", tx->tx_txg,
1143 dd->dd_space_towrite[tx->tx_txg&TXG_MASK] / 1024);
1144 dd->dd_space_towrite[tx->tx_txg&TXG_MASK] = 0;
1145 mutex_exit(&dd->dd_lock);
1146
1147 /* release the hold from dsl_dir_dirty */
1148 dmu_buf_rele(dd->dd_dbuf, dd);
1149 }
1150
1151 static uint64_t
1152 dsl_dir_space_towrite(dsl_dir_t *dd)
1153 {
1154 uint64_t space = 0;
1155
1156 ASSERT(MUTEX_HELD(&dd->dd_lock));
1157
1158 for (int i = 0; i < TXG_SIZE; i++) {
1159 space += dd->dd_space_towrite[i & TXG_MASK];
1160 ASSERT3U(dd->dd_space_towrite[i & TXG_MASK], >=, 0);
1161 }
1162 return (space);
1163 }
1164
1165 /*
1166 * How much space would dd have available if ancestor had delta applied
1167 * to it? If ondiskonly is set, we're only interested in what's
1168 * on-disk, not estimated pending changes.
1169 */
1170 uint64_t
1171 dsl_dir_space_available(dsl_dir_t *dd,
1172 dsl_dir_t *ancestor, int64_t delta, int ondiskonly)
1173 {
1174 uint64_t parentspace, myspace, quota, used;
1175
1176 /*
1177 * If there are no restrictions otherwise, assume we have
1178 * unlimited space available.
1179 */
1180 quota = UINT64_MAX;
1181 parentspace = UINT64_MAX;
1182
1183 if (dd->dd_parent != NULL) {
1184 parentspace = dsl_dir_space_available(dd->dd_parent,
1185 ancestor, delta, ondiskonly);
1186 }
1187
1188 mutex_enter(&dd->dd_lock);
1189 if (dsl_dir_phys(dd)->dd_quota != 0)
1190 quota = dsl_dir_phys(dd)->dd_quota;
1191 used = dsl_dir_phys(dd)->dd_used_bytes;
1192 if (!ondiskonly)
1193 used += dsl_dir_space_towrite(dd);
1194
1195 if (dd->dd_parent == NULL) {
1196 uint64_t poolsize = dsl_pool_adjustedsize(dd->dd_pool, FALSE);
1197 quota = MIN(quota, poolsize);
1198 }
1199
1200 if (dsl_dir_phys(dd)->dd_reserved > used && parentspace != UINT64_MAX) {
1201 /*
1202 * We have some space reserved, in addition to what our
1203 * parent gave us.
1204 */
1205 parentspace += dsl_dir_phys(dd)->dd_reserved - used;
1206 }
1207
1208 if (dd == ancestor) {
1209 ASSERT(delta <= 0);
1210 ASSERT(used >= -delta);
1211 used += delta;
1212 if (parentspace != UINT64_MAX)
1213 parentspace -= delta;
1214 }
1215
1216 if (used > quota) {
1217 /* over quota */
1218 myspace = 0;
1219 } else {
1220 /*
1221 * the lesser of the space provided by our parent and
1222 * the space left in our quota
1223 */
1224 myspace = MIN(parentspace, quota - used);
1225 }
1226
1227 mutex_exit(&dd->dd_lock);
1228
1229 return (myspace);
1230 }
1231
1232 struct tempreserve {
1233 list_node_t tr_node;
1234 dsl_dir_t *tr_ds;
1235 uint64_t tr_size;
1236 };
1237
1238 static int
1239 dsl_dir_tempreserve_impl(dsl_dir_t *dd, uint64_t asize, boolean_t netfree,
1240 boolean_t ignorequota, list_t *tr_list,
1241 dmu_tx_t *tx, boolean_t first)
1242 {
1243 uint64_t txg = tx->tx_txg;
1244 uint64_t quota;
1245 struct tempreserve *tr;
1246 int retval = EDQUOT;
1247 uint64_t ref_rsrv = 0;
1248
1249 ASSERT3U(txg, !=, 0);
1250 ASSERT3S(asize, >, 0);
1251
1252 mutex_enter(&dd->dd_lock);
1253
1254 /*
1255 * Check against the dsl_dir's quota. We don't add in the delta
1256 * when checking for over-quota because they get one free hit.
1257 */
1258 uint64_t est_inflight = dsl_dir_space_towrite(dd);
1259 for (int i = 0; i < TXG_SIZE; i++)
1260 est_inflight += dd->dd_tempreserved[i];
1261 uint64_t used_on_disk = dsl_dir_phys(dd)->dd_used_bytes;
1262
1263 /*
1264 * On the first iteration, fetch the dataset's used-on-disk and
1265 * refreservation values. Also, if checkrefquota is set, test if
1266 * allocating this space would exceed the dataset's refquota.
1267 */
1268 if (first && tx->tx_objset) {
1269 int error;
1270 dsl_dataset_t *ds = tx->tx_objset->os_dsl_dataset;
1271
1272 error = dsl_dataset_check_quota(ds, !netfree,
1273 asize, est_inflight, &used_on_disk, &ref_rsrv);
1274 if (error != 0) {
1275 mutex_exit(&dd->dd_lock);
1276 return (error);
1277 }
1278 }
1279
1280 /*
1281 * If this transaction will result in a net free of space,
1282 * we want to let it through.
1283 */
1284 if (ignorequota || netfree || dsl_dir_phys(dd)->dd_quota == 0)
1285 quota = UINT64_MAX;
1286 else
1287 quota = dsl_dir_phys(dd)->dd_quota;
1288
1289 /*
1290 * Adjust the quota against the actual pool size at the root
1291 * minus any outstanding deferred frees.
1292 * To ensure that it's possible to remove files from a full
1293 * pool without inducing transient overcommits, we throttle
1294 * netfree transactions against a quota that is slightly larger,
1295 * but still within the pool's allocation slop. In cases where
1296 * we're very close to full, this will allow a steady trickle of
1297 * removes to get through.
1298 */
1299 uint64_t deferred = 0;
1300 if (dd->dd_parent == NULL) {
1301 spa_t *spa = dd->dd_pool->dp_spa;
1302 uint64_t poolsize = dsl_pool_adjustedsize(dd->dd_pool, netfree);
1303 deferred = metaslab_class_get_deferred(spa_normal_class(spa));
1304 if (poolsize - deferred < quota) {
1305 quota = poolsize - deferred;
1306 retval = ENOSPC;
1307 }
1308 }
1309
1310 /*
1311 * If they are requesting more space, and our current estimate
1312 * is over quota, they get to try again unless the actual
1313 * on-disk is over quota and there are no pending changes (which
1314 * may free up space for us).
1315 */
1316 if (used_on_disk + est_inflight >= quota) {
1317 if (est_inflight > 0 || used_on_disk < quota ||
1318 (retval == ENOSPC && used_on_disk < quota + deferred))
1319 retval = ERESTART;
1320 dprintf_dd(dd, "failing: used=%lluK inflight = %lluK "
1321 "quota=%lluK tr=%lluK err=%d\n",
1322 used_on_disk>>10, est_inflight>>10,
1323 quota>>10, asize>>10, retval);
1324 mutex_exit(&dd->dd_lock);
1325 return (SET_ERROR(retval));
1326 }
1327
1328 /* We need to up our estimated delta before dropping dd_lock */
1329 dd->dd_tempreserved[txg & TXG_MASK] += asize;
1330
1331 uint64_t parent_rsrv = parent_delta(dd, used_on_disk + est_inflight,
1332 asize - ref_rsrv);
1333 mutex_exit(&dd->dd_lock);
1334
1335 tr = kmem_zalloc(sizeof (struct tempreserve), KM_SLEEP);
1336 tr->tr_ds = dd;
1337 tr->tr_size = asize;
1338 list_insert_tail(tr_list, tr);
1339
1340 /* see if it's OK with our parent */
1341 if (dd->dd_parent != NULL && parent_rsrv != 0) {
1342 boolean_t ismos = (dsl_dir_phys(dd)->dd_head_dataset_obj == 0);
1343
1344 return (dsl_dir_tempreserve_impl(dd->dd_parent,
1345 parent_rsrv, netfree, ismos, tr_list, tx, B_FALSE));
1346 } else {
1347 return (0);
1348 }
1349 }
1350
1351 /*
1352 * Reserve space in this dsl_dir, to be used in this tx's txg.
1353 * After the space has been dirtied (and dsl_dir_willuse_space()
1354 * has been called), the reservation should be canceled, using
1355 * dsl_dir_tempreserve_clear().
1356 */
1357 int
1358 dsl_dir_tempreserve_space(dsl_dir_t *dd, uint64_t lsize, uint64_t asize,
1359 boolean_t netfree, void **tr_cookiep, dmu_tx_t *tx)
1360 {
1361 int err;
1362 list_t *tr_list;
1363
1364 if (asize == 0) {
1365 *tr_cookiep = NULL;
1366 return (0);
1367 }
1368
1369 tr_list = kmem_alloc(sizeof (list_t), KM_SLEEP);
1370 list_create(tr_list, sizeof (struct tempreserve),
1371 offsetof(struct tempreserve, tr_node));
1372 ASSERT3S(asize, >, 0);
1373
1374 err = arc_tempreserve_space(lsize, tx->tx_txg);
1375 if (err == 0) {
1376 struct tempreserve *tr;
1377
1378 tr = kmem_zalloc(sizeof (struct tempreserve), KM_SLEEP);
1379 tr->tr_size = lsize;
1380 list_insert_tail(tr_list, tr);
1381 } else {
1382 if (err == EAGAIN) {
1383 /*
1384 * If arc_memory_throttle() detected that pageout
1385 * is running and we are low on memory, we delay new
1386 * non-pageout transactions to give pageout an
1387 * advantage.
1388 *
1389 * It is unfortunate to be delaying while the caller's
1390 * locks are held.
1391 */
1392 txg_delay(dd->dd_pool, tx->tx_txg,
1393 MSEC2NSEC(10), MSEC2NSEC(10));
1394 err = SET_ERROR(ERESTART);
1395 }
1396 }
1397
1398 if (err == 0) {
1399 err = dsl_dir_tempreserve_impl(dd, asize, netfree,
1400 B_FALSE, tr_list, tx, B_TRUE);
1401 }
1402
1403 if (err != 0)
1404 dsl_dir_tempreserve_clear(tr_list, tx);
1405 else
1406 *tr_cookiep = tr_list;
1407
1408 return (err);
1409 }
1410
1411 /*
1412 * Clear a temporary reservation that we previously made with
1413 * dsl_dir_tempreserve_space().
1414 */
1415 void
1416 dsl_dir_tempreserve_clear(void *tr_cookie, dmu_tx_t *tx)
1417 {
1418 int txgidx = tx->tx_txg & TXG_MASK;
1419 list_t *tr_list = tr_cookie;
1420 struct tempreserve *tr;
1421
1422 ASSERT3U(tx->tx_txg, !=, 0);
1423
1424 if (tr_cookie == NULL)
1425 return;
1426
1427 while ((tr = list_head(tr_list)) != NULL) {
1428 if (tr->tr_ds) {
1429 mutex_enter(&tr->tr_ds->dd_lock);
1430 ASSERT3U(tr->tr_ds->dd_tempreserved[txgidx], >=,
1431 tr->tr_size);
1432 tr->tr_ds->dd_tempreserved[txgidx] -= tr->tr_size;
1433 mutex_exit(&tr->tr_ds->dd_lock);
1434 } else {
1435 arc_tempreserve_clear(tr->tr_size);
1436 }
1437 list_remove(tr_list, tr);
1438 kmem_free(tr, sizeof (struct tempreserve));
1439 }
1440
1441 kmem_free(tr_list, sizeof (list_t));
1442 }
1443
1444 /*
1445 * This should be called from open context when we think we're going to write
1446 * or free space, for example when dirtying data. Be conservative; it's okay
1447 * to write less space or free more, but we don't want to write more or free
1448 * less than the amount specified.
1449 */
1450 void
1451 dsl_dir_willuse_space(dsl_dir_t *dd, int64_t space, dmu_tx_t *tx)
1452 {
1453 int64_t parent_space;
1454 uint64_t est_used;
1455
1456 mutex_enter(&dd->dd_lock);
1457 if (space > 0)
1458 dd->dd_space_towrite[tx->tx_txg & TXG_MASK] += space;
1459
1460 est_used = dsl_dir_space_towrite(dd) + dsl_dir_phys(dd)->dd_used_bytes;
1461 parent_space = parent_delta(dd, est_used, space);
1462 mutex_exit(&dd->dd_lock);
1463
1464 /* Make sure that we clean up dd_space_to* */
1465 dsl_dir_dirty(dd, tx);
1466
1467 /* XXX this is potentially expensive and unnecessary... */
1468 if (parent_space && dd->dd_parent)
1469 dsl_dir_willuse_space(dd->dd_parent, parent_space, tx);
1470 }
1471
1472 /* call from syncing context when we actually write/free space for this dd */
1473 void
1474 dsl_dir_diduse_space(dsl_dir_t *dd, dd_used_t type,
1475 int64_t used, int64_t compressed, int64_t uncompressed, dmu_tx_t *tx)
1476 {
1477 int64_t accounted_delta;
1478
1479 /*
1480 * dsl_dataset_set_refreservation_sync_impl() calls this with
1481 * dd_lock held, so that it can atomically update
1482 * ds->ds_reserved and the dsl_dir accounting, so that
1483 * dsl_dataset_check_quota() can see dataset and dir accounting
1484 * consistently.
1485 */
1486 boolean_t needlock = !MUTEX_HELD(&dd->dd_lock);
1487
1488 ASSERT(dmu_tx_is_syncing(tx));
1489 ASSERT(type < DD_USED_NUM);
1490
1491 dmu_buf_will_dirty(dd->dd_dbuf, tx);
1492
1493 if (needlock)
1494 mutex_enter(&dd->dd_lock);
1495 accounted_delta =
1496 parent_delta(dd, dsl_dir_phys(dd)->dd_used_bytes, used);
1497 ASSERT(used >= 0 || dsl_dir_phys(dd)->dd_used_bytes >= -used);
1498 ASSERT(compressed >= 0 ||
1499 dsl_dir_phys(dd)->dd_compressed_bytes >= -compressed);
1500 ASSERT(uncompressed >= 0 ||
1501 dsl_dir_phys(dd)->dd_uncompressed_bytes >= -uncompressed);
1502 dsl_dir_phys(dd)->dd_used_bytes += used;
1503 dsl_dir_phys(dd)->dd_uncompressed_bytes += uncompressed;
1504 dsl_dir_phys(dd)->dd_compressed_bytes += compressed;
1505
1506 if (dsl_dir_phys(dd)->dd_flags & DD_FLAG_USED_BREAKDOWN) {
1507 ASSERT(used > 0 ||
1508 dsl_dir_phys(dd)->dd_used_breakdown[type] >= -used);
1509 dsl_dir_phys(dd)->dd_used_breakdown[type] += used;
1510 #ifdef DEBUG
1511 dd_used_t t;
1512 uint64_t u = 0;
1513 for (t = 0; t < DD_USED_NUM; t++)
1514 u += dsl_dir_phys(dd)->dd_used_breakdown[t];
1515 ASSERT3U(u, ==, dsl_dir_phys(dd)->dd_used_bytes);
1516 #endif
1517 }
1518 if (needlock)
1519 mutex_exit(&dd->dd_lock);
1520
1521 if (dd->dd_parent != NULL) {
1522 dsl_dir_diduse_space(dd->dd_parent, DD_USED_CHILD,
1523 accounted_delta, compressed, uncompressed, tx);
1524 dsl_dir_transfer_space(dd->dd_parent,
1525 used - accounted_delta,
1526 DD_USED_CHILD_RSRV, DD_USED_CHILD, tx);
1527 }
1528 }
1529
1530 void
1531 dsl_dir_transfer_space(dsl_dir_t *dd, int64_t delta,
1532 dd_used_t oldtype, dd_used_t newtype, dmu_tx_t *tx)
1533 {
1534 ASSERT(dmu_tx_is_syncing(tx));
1535 ASSERT(oldtype < DD_USED_NUM);
1536 ASSERT(newtype < DD_USED_NUM);
1537
1538 if (delta == 0 ||
1539 !(dsl_dir_phys(dd)->dd_flags & DD_FLAG_USED_BREAKDOWN))
1540 return;
1541
1542 dmu_buf_will_dirty(dd->dd_dbuf, tx);
1543 mutex_enter(&dd->dd_lock);
1544 ASSERT(delta > 0 ?
1545 dsl_dir_phys(dd)->dd_used_breakdown[oldtype] >= delta :
1546 dsl_dir_phys(dd)->dd_used_breakdown[newtype] >= -delta);
1547 ASSERT(dsl_dir_phys(dd)->dd_used_bytes >= ABS(delta));
1548 dsl_dir_phys(dd)->dd_used_breakdown[oldtype] -= delta;
1549 dsl_dir_phys(dd)->dd_used_breakdown[newtype] += delta;
1550 mutex_exit(&dd->dd_lock);
1551 }
1552
1553 typedef struct dsl_dir_set_qr_arg {
1554 const char *ddsqra_name;
1555 zprop_source_t ddsqra_source;
1556 uint64_t ddsqra_value;
1557 } dsl_dir_set_qr_arg_t;
1558
1559 static int
1560 dsl_dir_set_quota_check(void *arg, dmu_tx_t *tx)
1561 {
1562 dsl_dir_set_qr_arg_t *ddsqra = arg;
1563 dsl_pool_t *dp = dmu_tx_pool(tx);
1564 dsl_dataset_t *ds;
1565 int error;
1566 uint64_t towrite, newval;
1567
1568 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds);
1569 if (error != 0)
1570 return (error);
1571
1572 error = dsl_prop_predict(ds->ds_dir, "quota",
1573 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval);
1574 if (error != 0) {
1575 dsl_dataset_rele(ds, FTAG);
1576 return (error);
1577 }
1578
1579 if (newval == 0) {
1580 dsl_dataset_rele(ds, FTAG);
1581 return (0);
1582 }
1583
1584 mutex_enter(&ds->ds_dir->dd_lock);
1585 /*
1586 * If we are doing the preliminary check in open context, and
1587 * there are pending changes, then don't fail it, since the
1588 * pending changes could under-estimate the amount of space to be
1589 * freed up.
1590 */
1591 towrite = dsl_dir_space_towrite(ds->ds_dir);
1592 if ((dmu_tx_is_syncing(tx) || towrite == 0) &&
1593 (newval < dsl_dir_phys(ds->ds_dir)->dd_reserved ||
1594 newval < dsl_dir_phys(ds->ds_dir)->dd_used_bytes + towrite)) {
1595 error = SET_ERROR(ENOSPC);
1596 }
1597 mutex_exit(&ds->ds_dir->dd_lock);
1598 dsl_dataset_rele(ds, FTAG);
1599 return (error);
1600 }
1601
1602 static void
1603 dsl_dir_set_quota_sync(void *arg, dmu_tx_t *tx)
1604 {
1605 dsl_dir_set_qr_arg_t *ddsqra = arg;
1606 dsl_pool_t *dp = dmu_tx_pool(tx);
1607 dsl_dataset_t *ds;
1608 uint64_t newval;
1609
1610 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds));
1611
1612 if (spa_version(dp->dp_spa) >= SPA_VERSION_RECVD_PROPS) {
1613 dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_QUOTA),
1614 ddsqra->ddsqra_source, sizeof (ddsqra->ddsqra_value), 1,
1615 &ddsqra->ddsqra_value, tx);
1616
1617 VERIFY0(dsl_prop_get_int_ds(ds,
1618 zfs_prop_to_name(ZFS_PROP_QUOTA), &newval));
1619 } else {
1620 newval = ddsqra->ddsqra_value;
1621 spa_history_log_internal_ds(ds, "set", tx, "%s=%lld",
1622 zfs_prop_to_name(ZFS_PROP_QUOTA), (longlong_t)newval);
1623 }
1624
1625 dmu_buf_will_dirty(ds->ds_dir->dd_dbuf, tx);
1626 mutex_enter(&ds->ds_dir->dd_lock);
1627 dsl_dir_phys(ds->ds_dir)->dd_quota = newval;
1628 mutex_exit(&ds->ds_dir->dd_lock);
1629 dsl_dataset_rele(ds, FTAG);
1630 }
1631
1632 int
1633 dsl_dir_set_quota(const char *ddname, zprop_source_t source, uint64_t quota)
1634 {
1635 dsl_dir_set_qr_arg_t ddsqra;
1636
1637 ddsqra.ddsqra_name = ddname;
1638 ddsqra.ddsqra_source = source;
1639 ddsqra.ddsqra_value = quota;
1640
1641 return (dsl_sync_task(ddname, dsl_dir_set_quota_check,
1642 dsl_dir_set_quota_sync, &ddsqra, 0, ZFS_SPACE_CHECK_NONE));
1643 }
1644
1645 int
1646 dsl_dir_set_reservation_check(void *arg, dmu_tx_t *tx)
1647 {
1648 dsl_dir_set_qr_arg_t *ddsqra = arg;
1649 dsl_pool_t *dp = dmu_tx_pool(tx);
1650 dsl_dataset_t *ds;
1651 dsl_dir_t *dd;
1652 uint64_t newval, used, avail;
1653 int error;
1654
1655 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds);
1656 if (error != 0)
1657 return (error);
1658 dd = ds->ds_dir;
1659
1660 /*
1661 * If we are doing the preliminary check in open context, the
1662 * space estimates may be inaccurate.
1663 */
1664 if (!dmu_tx_is_syncing(tx)) {
1665 dsl_dataset_rele(ds, FTAG);
1666 return (0);
1667 }
1668
1669 error = dsl_prop_predict(ds->ds_dir,
1670 zfs_prop_to_name(ZFS_PROP_RESERVATION),
1671 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval);
1672 if (error != 0) {
1673 dsl_dataset_rele(ds, FTAG);
1674 return (error);
1675 }
1676
1677 mutex_enter(&dd->dd_lock);
1678 used = dsl_dir_phys(dd)->dd_used_bytes;
1679 mutex_exit(&dd->dd_lock);
1680
1681 if (dd->dd_parent) {
1682 avail = dsl_dir_space_available(dd->dd_parent,
1683 NULL, 0, FALSE);
1684 } else {
1685 avail = dsl_pool_adjustedsize(dd->dd_pool, B_FALSE) - used;
1686 }
1687
1688 if (MAX(used, newval) > MAX(used, dsl_dir_phys(dd)->dd_reserved)) {
1689 uint64_t delta = MAX(used, newval) -
1690 MAX(used, dsl_dir_phys(dd)->dd_reserved);
1691
1692 if (delta > avail ||
1693 (dsl_dir_phys(dd)->dd_quota > 0 &&
1694 newval > dsl_dir_phys(dd)->dd_quota))
1695 error = SET_ERROR(ENOSPC);
1696 }
1697
1698 dsl_dataset_rele(ds, FTAG);
1699 return (error);
1700 }
1701
1702 void
1703 dsl_dir_set_reservation_sync_impl(dsl_dir_t *dd, uint64_t value, dmu_tx_t *tx)
1704 {
1705 uint64_t used;
1706 int64_t delta;
1707
1708 dmu_buf_will_dirty(dd->dd_dbuf, tx);
1709
1710 mutex_enter(&dd->dd_lock);
1711 used = dsl_dir_phys(dd)->dd_used_bytes;
1712 delta = MAX(used, value) - MAX(used, dsl_dir_phys(dd)->dd_reserved);
1713 dsl_dir_phys(dd)->dd_reserved = value;
1714
1715 if (dd->dd_parent != NULL) {
1716 /* Roll up this additional usage into our ancestors */
1717 dsl_dir_diduse_space(dd->dd_parent, DD_USED_CHILD_RSRV,
1718 delta, 0, 0, tx);
1719 }
1720 mutex_exit(&dd->dd_lock);
1721 }
1722
1723
1724 static void
1725 dsl_dir_set_reservation_sync(void *arg, dmu_tx_t *tx)
1726 {
1727 dsl_dir_set_qr_arg_t *ddsqra = arg;
1728 dsl_pool_t *dp = dmu_tx_pool(tx);
1729 dsl_dataset_t *ds;
1730 uint64_t newval;
1731
1732 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds));
1733
1734 if (spa_version(dp->dp_spa) >= SPA_VERSION_RECVD_PROPS) {
1735 dsl_prop_set_sync_impl(ds,
1736 zfs_prop_to_name(ZFS_PROP_RESERVATION),
1737 ddsqra->ddsqra_source, sizeof (ddsqra->ddsqra_value), 1,
1738 &ddsqra->ddsqra_value, tx);
1739
1740 VERIFY0(dsl_prop_get_int_ds(ds,
1741 zfs_prop_to_name(ZFS_PROP_RESERVATION), &newval));
1742 } else {
1743 newval = ddsqra->ddsqra_value;
1744 spa_history_log_internal_ds(ds, "set", tx, "%s=%lld",
1745 zfs_prop_to_name(ZFS_PROP_RESERVATION),
1746 (longlong_t)newval);
1747 }
1748
1749 dsl_dir_set_reservation_sync_impl(ds->ds_dir, newval, tx);
1750 dsl_dataset_rele(ds, FTAG);
1751 }
1752
1753 int
1754 dsl_dir_set_reservation(const char *ddname, zprop_source_t source,
1755 uint64_t reservation)
1756 {
1757 dsl_dir_set_qr_arg_t ddsqra;
1758
1759 ddsqra.ddsqra_name = ddname;
1760 ddsqra.ddsqra_source = source;
1761 ddsqra.ddsqra_value = reservation;
1762
1763 return (dsl_sync_task(ddname, dsl_dir_set_reservation_check,
1764 dsl_dir_set_reservation_sync, &ddsqra, 0, ZFS_SPACE_CHECK_NONE));
1765 }
1766
1767 static dsl_dir_t *
1768 closest_common_ancestor(dsl_dir_t *ds1, dsl_dir_t *ds2)
1769 {
1770 for (; ds1; ds1 = ds1->dd_parent) {
1771 dsl_dir_t *dd;
1772 for (dd = ds2; dd; dd = dd->dd_parent) {
1773 if (ds1 == dd)
1774 return (dd);
1775 }
1776 }
1777 return (NULL);
1778 }
1779
1780 /*
1781 * If delta is applied to dd, how much of that delta would be applied to
1782 * ancestor? Syncing context only.
1783 */
1784 static int64_t
1785 would_change(dsl_dir_t *dd, int64_t delta, dsl_dir_t *ancestor)
1786 {
1787 if (dd == ancestor)
1788 return (delta);
1789
1790 mutex_enter(&dd->dd_lock);
1791 delta = parent_delta(dd, dsl_dir_phys(dd)->dd_used_bytes, delta);
1792 mutex_exit(&dd->dd_lock);
1793 return (would_change(dd->dd_parent, delta, ancestor));
1794 }
1795
1796 typedef struct dsl_dir_rename_arg {
1797 const char *ddra_oldname;
1798 const char *ddra_newname;
1799 cred_t *ddra_cred;
1800 } dsl_dir_rename_arg_t;
1801
1802 /* ARGSUSED */
1803 static int
1804 dsl_valid_rename(dsl_pool_t *dp, dsl_dataset_t *ds, void *arg)
1805 {
1806 int *deltap = arg;
1807 char namebuf[ZFS_MAX_DATASET_NAME_LEN];
1808
1809 dsl_dataset_name(ds, namebuf);
1810
1811 if (strlen(namebuf) + *deltap >= ZFS_MAX_DATASET_NAME_LEN)
1812 return (SET_ERROR(ENAMETOOLONG));
1813 return (0);
1814 }
1815
1816 static int
1817 dsl_dir_rename_check(void *arg, dmu_tx_t *tx)
1818 {
1819 dsl_dir_rename_arg_t *ddra = arg;
1820 dsl_pool_t *dp = dmu_tx_pool(tx);
1821 dsl_dir_t *dd, *newparent;
1822 const char *mynewname;
1823 int error;
1824 int delta = strlen(ddra->ddra_newname) - strlen(ddra->ddra_oldname);
1825
1826 /* target dir should exist */
1827 error = dsl_dir_hold(dp, ddra->ddra_oldname, FTAG, &dd, NULL);
1828 if (error != 0)
1829 return (error);
1830
1831 /* new parent should exist */
1832 error = dsl_dir_hold(dp, ddra->ddra_newname, FTAG,
1833 &newparent, &mynewname);
1834 if (error != 0) {
1835 dsl_dir_rele(dd, FTAG);
1836 return (error);
1837 }
1838
1839 /* can't rename to different pool */
1840 if (dd->dd_pool != newparent->dd_pool) {
1841 dsl_dir_rele(newparent, FTAG);
1842 dsl_dir_rele(dd, FTAG);
1843 return (SET_ERROR(ENXIO));
1844 }
1845
1846 /* new name should not already exist */
1847 if (mynewname == NULL) {
1848 dsl_dir_rele(newparent, FTAG);
1849 dsl_dir_rele(dd, FTAG);
1850 return (SET_ERROR(EEXIST));
1851 }
1852
1853 /* if the name length is growing, validate child name lengths */
1854 if (delta > 0) {
1855 error = dmu_objset_find_dp(dp, dd->dd_object, dsl_valid_rename,
1856 &delta, DS_FIND_CHILDREN | DS_FIND_SNAPSHOTS);
1857 if (error != 0) {
1858 dsl_dir_rele(newparent, FTAG);
1859 dsl_dir_rele(dd, FTAG);
1860 return (error);
1861 }
1862 }
1863
1864 if (dmu_tx_is_syncing(tx)) {
1865 if (spa_feature_is_active(dp->dp_spa,
1866 SPA_FEATURE_FS_SS_LIMIT)) {
1867 /*
1868 * Although this is the check function and we don't
1869 * normally make on-disk changes in check functions,
1870 * we need to do that here.
1871 *
1872 * Ensure this portion of the tree's counts have been
1873 * initialized in case the new parent has limits set.
1874 */
1875 dsl_dir_init_fs_ss_count(dd, tx);
1876 }
1877 }
1878
1879 if (newparent != dd->dd_parent) {
1880 /* is there enough space? */
1881 uint64_t myspace =
1882 MAX(dsl_dir_phys(dd)->dd_used_bytes,
1883 dsl_dir_phys(dd)->dd_reserved);
1884 objset_t *os = dd->dd_pool->dp_meta_objset;
1885 uint64_t fs_cnt = 0;
1886 uint64_t ss_cnt = 0;
1887
1888 if (dsl_dir_is_zapified(dd)) {
1889 int err;
1890
1891 err = zap_lookup(os, dd->dd_object,
1892 DD_FIELD_FILESYSTEM_COUNT, sizeof (fs_cnt), 1,
1893 &fs_cnt);
1894 if (err != ENOENT && err != 0) {
1895 dsl_dir_rele(newparent, FTAG);
1896 dsl_dir_rele(dd, FTAG);
1897 return (err);
1898 }
1899
1900 /*
1901 * have to add 1 for the filesystem itself that we're
1902 * moving
1903 */
1904 fs_cnt++;
1905
1906 err = zap_lookup(os, dd->dd_object,
1907 DD_FIELD_SNAPSHOT_COUNT, sizeof (ss_cnt), 1,
1908 &ss_cnt);
1909 if (err != ENOENT && err != 0) {
1910 dsl_dir_rele(newparent, FTAG);
1911 dsl_dir_rele(dd, FTAG);
1912 return (err);
1913 }
1914 }
1915
1916 /* no rename into our descendant */
1917 if (closest_common_ancestor(dd, newparent) == dd) {
1918 dsl_dir_rele(newparent, FTAG);
1919 dsl_dir_rele(dd, FTAG);
1920 return (SET_ERROR(EINVAL));
1921 }
1922
1923 error = dsl_dir_transfer_possible(dd->dd_parent,
1924 newparent, fs_cnt, ss_cnt, myspace, ddra->ddra_cred);
1925 if (error != 0) {
1926 dsl_dir_rele(newparent, FTAG);
1927 dsl_dir_rele(dd, FTAG);
1928 return (error);
1929 }
1930 }
1931
1932 dsl_dir_rele(newparent, FTAG);
1933 dsl_dir_rele(dd, FTAG);
1934 return (0);
1935 }
1936
1937 static void
1938 dsl_dir_rename_sync(void *arg, dmu_tx_t *tx)
1939 {
1940 dsl_dir_rename_arg_t *ddra = arg;
1941 dsl_pool_t *dp = dmu_tx_pool(tx);
1942 dsl_dir_t *dd, *newparent;
1943 const char *mynewname;
1944 int error;
1945 objset_t *mos = dp->dp_meta_objset;
1946
1947 VERIFY0(dsl_dir_hold(dp, ddra->ddra_oldname, FTAG, &dd, NULL));
1948 VERIFY0(dsl_dir_hold(dp, ddra->ddra_newname, FTAG, &newparent,
1949 &mynewname));
1950
1951 /* Log this before we change the name. */
1952 spa_history_log_internal_dd(dd, "rename", tx,
1953 "-> %s", ddra->ddra_newname);
1954
1955 if (newparent != dd->dd_parent) {
1956 objset_t *os = dd->dd_pool->dp_meta_objset;
1957 uint64_t fs_cnt = 0;
1958 uint64_t ss_cnt = 0;
1959
1960 /*
1961 * We already made sure the dd counts were initialized in the
1962 * check function.
1963 */
1964 if (spa_feature_is_active(dp->dp_spa,
1965 SPA_FEATURE_FS_SS_LIMIT)) {
1966 VERIFY0(zap_lookup(os, dd->dd_object,
1967 DD_FIELD_FILESYSTEM_COUNT, sizeof (fs_cnt), 1,
1968 &fs_cnt));
1969 /* add 1 for the filesystem itself that we're moving */
1970 fs_cnt++;
1971
1972 VERIFY0(zap_lookup(os, dd->dd_object,
1973 DD_FIELD_SNAPSHOT_COUNT, sizeof (ss_cnt), 1,
1974 &ss_cnt));
1975 }
1976
1977 dsl_fs_ss_count_adjust(dd->dd_parent, -fs_cnt,
1978 DD_FIELD_FILESYSTEM_COUNT, tx);
1979 dsl_fs_ss_count_adjust(newparent, fs_cnt,
1980 DD_FIELD_FILESYSTEM_COUNT, tx);
1981
1982 dsl_fs_ss_count_adjust(dd->dd_parent, -ss_cnt,
1983 DD_FIELD_SNAPSHOT_COUNT, tx);
1984 dsl_fs_ss_count_adjust(newparent, ss_cnt,
1985 DD_FIELD_SNAPSHOT_COUNT, tx);
1986
1987 dsl_dir_diduse_space(dd->dd_parent, DD_USED_CHILD,
1988 -dsl_dir_phys(dd)->dd_used_bytes,
1989 -dsl_dir_phys(dd)->dd_compressed_bytes,
1990 -dsl_dir_phys(dd)->dd_uncompressed_bytes, tx);
1991 dsl_dir_diduse_space(newparent, DD_USED_CHILD,
1992 dsl_dir_phys(dd)->dd_used_bytes,
1993 dsl_dir_phys(dd)->dd_compressed_bytes,
1994 dsl_dir_phys(dd)->dd_uncompressed_bytes, tx);
1995
1996 if (dsl_dir_phys(dd)->dd_reserved >
1997 dsl_dir_phys(dd)->dd_used_bytes) {
1998 uint64_t unused_rsrv = dsl_dir_phys(dd)->dd_reserved -
1999 dsl_dir_phys(dd)->dd_used_bytes;
2000
2001 dsl_dir_diduse_space(dd->dd_parent, DD_USED_CHILD_RSRV,
2002 -unused_rsrv, 0, 0, tx);
2003 dsl_dir_diduse_space(newparent, DD_USED_CHILD_RSRV,
2004 unused_rsrv, 0, 0, tx);
2005 }
2006 }
2007
2008 dmu_buf_will_dirty(dd->dd_dbuf, tx);
2009
2010 /* remove from old parent zapobj */
2011 error = zap_remove(mos,
2012 dsl_dir_phys(dd->dd_parent)->dd_child_dir_zapobj,
2013 dd->dd_myname, tx);
2014 ASSERT0(error);
2015
2016 (void) strcpy(dd->dd_myname, mynewname);
2017 dsl_dir_rele(dd->dd_parent, dd);
2018 dsl_dir_phys(dd)->dd_parent_obj = newparent->dd_object;
2019 VERIFY0(dsl_dir_hold_obj(dp,
2020 newparent->dd_object, NULL, dd, &dd->dd_parent));
2021
2022 /* add to new parent zapobj */
2023 VERIFY0(zap_add(mos, dsl_dir_phys(newparent)->dd_child_dir_zapobj,
2024 dd->dd_myname, 8, 1, &dd->dd_object, tx));
2025
2026 dsl_prop_notify_all(dd);
2027
2028 dsl_dir_rele(newparent, FTAG);
2029 dsl_dir_rele(dd, FTAG);
2030 }
2031
2032 int
2033 dsl_dir_rename(const char *oldname, const char *newname)
2034 {
2035 dsl_dir_rename_arg_t ddra;
2036
2037 ddra.ddra_oldname = oldname;
2038 ddra.ddra_newname = newname;
2039 ddra.ddra_cred = CRED();
2040
2041 return (dsl_sync_task(oldname,
2042 dsl_dir_rename_check, dsl_dir_rename_sync, &ddra,
2043 3, ZFS_SPACE_CHECK_RESERVED));
2044 }
2045
2046 int
2047 dsl_dir_transfer_possible(dsl_dir_t *sdd, dsl_dir_t *tdd,
2048 uint64_t fs_cnt, uint64_t ss_cnt, uint64_t space, cred_t *cr)
2049 {
2050 dsl_dir_t *ancestor;
2051 int64_t adelta;
2052 uint64_t avail;
2053 int err;
2054
2055 ancestor = closest_common_ancestor(sdd, tdd);
2056 adelta = would_change(sdd, -space, ancestor);
2057 avail = dsl_dir_space_available(tdd, ancestor, adelta, FALSE);
2058 if (avail < space)
2059 return (SET_ERROR(ENOSPC));
2060
2061 err = dsl_fs_ss_limit_check(tdd, fs_cnt, ZFS_PROP_FILESYSTEM_LIMIT,
2062 ancestor, cr);
2063 if (err != 0)
2064 return (err);
2065 err = dsl_fs_ss_limit_check(tdd, ss_cnt, ZFS_PROP_SNAPSHOT_LIMIT,
2066 ancestor, cr);
2067 if (err != 0)
2068 return (err);
2069
2070 return (0);
2071 }
2072
2073 timestruc_t
2074 dsl_dir_snap_cmtime(dsl_dir_t *dd)
2075 {
2076 timestruc_t t;
2077
2078 mutex_enter(&dd->dd_lock);
2079 t = dd->dd_snap_cmtime;
2080 mutex_exit(&dd->dd_lock);
2081
2082 return (t);
2083 }
2084
2085 void
2086 dsl_dir_snap_cmtime_update(dsl_dir_t *dd)
2087 {
2088 timestruc_t t;
2089
2090 gethrestime(&t);
2091 mutex_enter(&dd->dd_lock);
2092 dd->dd_snap_cmtime = t;
2093 mutex_exit(&dd->dd_lock);
2094 }
2095
2096 void
2097 dsl_dir_zapify(dsl_dir_t *dd, dmu_tx_t *tx)
2098 {
2099 objset_t *mos = dd->dd_pool->dp_meta_objset;
2100 dmu_object_zapify(mos, dd->dd_object, DMU_OT_DSL_DIR, tx);
2101 }
2102
2103 boolean_t
2104 dsl_dir_is_zapified(dsl_dir_t *dd)
2105 {
2106 dmu_object_info_t doi;
2107
2108 dmu_object_info_from_db(dd->dd_dbuf, &doi);
2109 return (doi.doi_type == DMU_OTN_ZAP_METADATA);
2110 }