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 by Delphix. All rights reserved.
  24  */
  25 
  26 #include <sys/zfs_context.h>
  27 #include <sys/dmu.h>
  28 #include <sys/dmu_objset.h>
  29 #include <sys/dmu_tx.h>
  30 #include <sys/dsl_dataset.h>
  31 #include <sys/dsl_dir.h>
  32 #include <sys/dsl_prop.h>
  33 #include <sys/dsl_synctask.h>
  34 #include <sys/spa.h>
  35 #include <sys/zap.h>
  36 #include <sys/fs/zfs.h>
  37 
  38 #include "zfs_prop.h"
  39 
  40 #define ZPROP_INHERIT_SUFFIX "$inherit"
  41 #define ZPROP_RECVD_SUFFIX "$recvd"
  42 
  43 static int
  44 dodefault(const char *propname, int intsz, int numints, void *buf)
  45 {
  46         zfs_prop_t prop;
  47 
  48         /*
  49          * The setonce properties are read-only, BUT they still
  50          * have a default value that can be used as the initial
  51          * value.
  52          */
  53         if ((prop = zfs_name_to_prop(propname)) == ZPROP_INVAL ||
  54             (zfs_prop_readonly(prop) && !zfs_prop_setonce(prop)))
  55                 return (ENOENT);
  56 
  57         if (zfs_prop_get_type(prop) == PROP_TYPE_STRING) {
  58                 if (intsz != 1)
  59                         return (EOVERFLOW);
  60                 (void) strncpy(buf, zfs_prop_default_string(prop),
  61                     numints);
  62         } else {
  63                 if (intsz != 8 || numints < 1)
  64                         return (EOVERFLOW);
  65 
  66                 *(uint64_t *)buf = zfs_prop_default_numeric(prop);
  67         }
  68 
  69         return (0);
  70 }
  71 
  72 int
  73 dsl_prop_get_dd(dsl_dir_t *dd, const char *propname,
  74     int intsz, int numints, void *buf, char *setpoint, boolean_t snapshot)
  75 {
  76         int err = ENOENT;
  77         dsl_dir_t *target = dd;
  78         objset_t *mos = dd->dd_pool->dp_meta_objset;
  79         zfs_prop_t prop;
  80         boolean_t inheritable;
  81         boolean_t inheriting = B_FALSE;
  82         char *inheritstr;
  83         char *recvdstr;
  84 
  85         ASSERT(RW_LOCK_HELD(&dd->dd_pool->dp_config_rwlock));
  86 
  87         if (setpoint)
  88                 setpoint[0] = '\0';
  89 
  90         prop = zfs_name_to_prop(propname);
  91         inheritable = (prop == ZPROP_INVAL || zfs_prop_inheritable(prop));
  92         inheritstr = kmem_asprintf("%s%s", propname, ZPROP_INHERIT_SUFFIX);
  93         recvdstr = kmem_asprintf("%s%s", propname, ZPROP_RECVD_SUFFIX);
  94 
  95         /*
  96          * Note: dd may become NULL, therefore we shouldn't dereference it
  97          * after this loop.
  98          */
  99         for (; dd != NULL; dd = dd->dd_parent) {
 100                 ASSERT(RW_LOCK_HELD(&dd->dd_pool->dp_config_rwlock));
 101 
 102                 if (dd != target || snapshot) {
 103                         if (!inheritable)
 104                                 break;
 105                         inheriting = B_TRUE;
 106                 }
 107 
 108                 /* Check for a local value. */
 109                 err = zap_lookup(mos, dd->dd_phys->dd_props_zapobj, propname,
 110                     intsz, numints, buf);
 111                 if (err != ENOENT) {
 112                         if (setpoint != NULL && err == 0)
 113                                 dsl_dir_name(dd, setpoint);
 114                         break;
 115                 }
 116 
 117                 /*
 118                  * Skip the check for a received value if there is an explicit
 119                  * inheritance entry.
 120                  */
 121                 err = zap_contains(mos, dd->dd_phys->dd_props_zapobj,
 122                     inheritstr);
 123                 if (err != 0 && err != ENOENT)
 124                         break;
 125 
 126                 if (err == ENOENT) {
 127                         /* Check for a received value. */
 128                         err = zap_lookup(mos, dd->dd_phys->dd_props_zapobj,
 129                             recvdstr, intsz, numints, buf);
 130                         if (err != ENOENT) {
 131                                 if (setpoint != NULL && err == 0) {
 132                                         if (inheriting) {
 133                                                 dsl_dir_name(dd, setpoint);
 134                                         } else {
 135                                                 (void) strcpy(setpoint,
 136                                                     ZPROP_SOURCE_VAL_RECVD);
 137                                         }
 138                                 }
 139                                 break;
 140                         }
 141                 }
 142 
 143                 /*
 144                  * If we found an explicit inheritance entry, err is zero even
 145                  * though we haven't yet found the value, so reinitializing err
 146                  * at the end of the loop (instead of at the beginning) ensures
 147                  * that err has a valid post-loop value.
 148                  */
 149                 err = ENOENT;
 150         }
 151 
 152         if (err == ENOENT)
 153                 err = dodefault(propname, intsz, numints, buf);
 154 
 155         strfree(inheritstr);
 156         strfree(recvdstr);
 157 
 158         return (err);
 159 }
 160 
 161 int
 162 dsl_prop_get_ds(dsl_dataset_t *ds, const char *propname,
 163     int intsz, int numints, void *buf, char *setpoint)
 164 {
 165         zfs_prop_t prop = zfs_name_to_prop(propname);
 166         boolean_t inheritable;
 167         boolean_t snapshot;
 168         uint64_t zapobj;
 169 
 170         ASSERT(RW_LOCK_HELD(&ds->ds_dir->dd_pool->dp_config_rwlock));
 171         inheritable = (prop == ZPROP_INVAL || zfs_prop_inheritable(prop));
 172         snapshot = (ds->ds_phys != NULL && dsl_dataset_is_snapshot(ds));
 173         zapobj = (ds->ds_phys == NULL ? 0 : ds->ds_phys->ds_props_obj);
 174 
 175         if (zapobj != 0) {
 176                 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
 177                 int err;
 178 
 179                 ASSERT(snapshot);
 180 
 181                 /* Check for a local value. */
 182                 err = zap_lookup(mos, zapobj, propname, intsz, numints, buf);
 183                 if (err != ENOENT) {
 184                         if (setpoint != NULL && err == 0)
 185                                 dsl_dataset_name(ds, setpoint);
 186                         return (err);
 187                 }
 188 
 189                 /*
 190                  * Skip the check for a received value if there is an explicit
 191                  * inheritance entry.
 192                  */
 193                 if (inheritable) {
 194                         char *inheritstr = kmem_asprintf("%s%s", propname,
 195                             ZPROP_INHERIT_SUFFIX);
 196                         err = zap_contains(mos, zapobj, inheritstr);
 197                         strfree(inheritstr);
 198                         if (err != 0 && err != ENOENT)
 199                                 return (err);
 200                 }
 201 
 202                 if (err == ENOENT) {
 203                         /* Check for a received value. */
 204                         char *recvdstr = kmem_asprintf("%s%s", propname,
 205                             ZPROP_RECVD_SUFFIX);
 206                         err = zap_lookup(mos, zapobj, recvdstr,
 207                             intsz, numints, buf);
 208                         strfree(recvdstr);
 209                         if (err != ENOENT) {
 210                                 if (setpoint != NULL && err == 0)
 211                                         (void) strcpy(setpoint,
 212                                             ZPROP_SOURCE_VAL_RECVD);
 213                                 return (err);
 214                         }
 215                 }
 216         }
 217 
 218         return (dsl_prop_get_dd(ds->ds_dir, propname,
 219             intsz, numints, buf, setpoint, snapshot));
 220 }
 221 
 222 /*
 223  * Register interest in the named property.  We'll call the callback
 224  * once to notify it of the current property value, and again each time
 225  * the property changes, until this callback is unregistered.
 226  *
 227  * Return 0 on success, errno if the prop is not an integer value.
 228  */
 229 int
 230 dsl_prop_register(dsl_dataset_t *ds, const char *propname,
 231     dsl_prop_changed_cb_t *callback, void *cbarg)
 232 {
 233         dsl_dir_t *dd = ds->ds_dir;
 234         dsl_pool_t *dp = dd->dd_pool;
 235         uint64_t value;
 236         dsl_prop_cb_record_t *cbr;
 237         int err;
 238         int need_rwlock;
 239 
 240         need_rwlock = !RW_WRITE_HELD(&dp->dp_config_rwlock);
 241         if (need_rwlock)
 242                 rw_enter(&dp->dp_config_rwlock, RW_READER);
 243 
 244         err = dsl_prop_get_ds(ds, propname, 8, 1, &value, NULL);
 245         if (err != 0) {
 246                 if (need_rwlock)
 247                         rw_exit(&dp->dp_config_rwlock);
 248                 return (err);
 249         }
 250 
 251         cbr = kmem_alloc(sizeof (dsl_prop_cb_record_t), KM_SLEEP);
 252         cbr->cbr_ds = ds;
 253         cbr->cbr_propname = kmem_alloc(strlen(propname)+1, KM_SLEEP);
 254         (void) strcpy((char *)cbr->cbr_propname, propname);
 255         cbr->cbr_func = callback;
 256         cbr->cbr_arg = cbarg;
 257         mutex_enter(&dd->dd_lock);
 258         list_insert_head(&dd->dd_prop_cbs, cbr);
 259         mutex_exit(&dd->dd_lock);
 260 
 261         cbr->cbr_func(cbr->cbr_arg, value);
 262 
 263         if (need_rwlock)
 264                 rw_exit(&dp->dp_config_rwlock);
 265         return (0);
 266 }
 267 
 268 int
 269 dsl_prop_get(const char *dsname, const char *propname,
 270     int intsz, int numints, void *buf, char *setpoint)
 271 {
 272         dsl_dataset_t *ds;
 273         int err;
 274 
 275         err = dsl_dataset_hold(dsname, FTAG, &ds);
 276         if (err)
 277                 return (err);
 278 
 279         rw_enter(&ds->ds_dir->dd_pool->dp_config_rwlock, RW_READER);
 280         err = dsl_prop_get_ds(ds, propname, intsz, numints, buf, setpoint);
 281         rw_exit(&ds->ds_dir->dd_pool->dp_config_rwlock);
 282 
 283         dsl_dataset_rele(ds, FTAG);
 284         return (err);
 285 }
 286 
 287 /*
 288  * Get the current property value.  It may have changed by the time this
 289  * function returns, so it is NOT safe to follow up with
 290  * dsl_prop_register() and assume that the value has not changed in
 291  * between.
 292  *
 293  * Return 0 on success, ENOENT if ddname is invalid.
 294  */
 295 int
 296 dsl_prop_get_integer(const char *ddname, const char *propname,
 297     uint64_t *valuep, char *setpoint)
 298 {
 299         return (dsl_prop_get(ddname, propname, 8, 1, valuep, setpoint));
 300 }
 301 
 302 void
 303 dsl_prop_setarg_init_uint64(dsl_prop_setarg_t *psa, const char *propname,
 304     zprop_source_t source, uint64_t *value)
 305 {
 306         psa->psa_name = propname;
 307         psa->psa_source = source;
 308         psa->psa_intsz = 8;
 309         psa->psa_numints = 1;
 310         psa->psa_value = value;
 311 
 312         psa->psa_effective_value = -1ULL;
 313 }
 314 
 315 /*
 316  * Predict the effective value of the given special property if it were set with
 317  * the given value and source. This is not a general purpose function. It exists
 318  * only to handle the special requirements of the quota and reservation
 319  * properties. The fact that these properties are non-inheritable greatly
 320  * simplifies the prediction logic.
 321  *
 322  * Returns 0 on success, a positive error code on failure, or -1 if called with
 323  * a property not handled by this function.
 324  */
 325 int
 326 dsl_prop_predict_sync(dsl_dir_t *dd, dsl_prop_setarg_t *psa)
 327 {
 328         const char *propname = psa->psa_name;
 329         zfs_prop_t prop = zfs_name_to_prop(propname);
 330         zprop_source_t source = psa->psa_source;
 331         objset_t *mos;
 332         uint64_t zapobj;
 333         uint64_t version;
 334         char *recvdstr;
 335         int err = 0;
 336 
 337         switch (prop) {
 338         case ZFS_PROP_QUOTA:
 339         case ZFS_PROP_RESERVATION:
 340         case ZFS_PROP_REFQUOTA:
 341         case ZFS_PROP_REFRESERVATION:
 342                 break;
 343         default:
 344                 return (-1);
 345         }
 346 
 347         mos = dd->dd_pool->dp_meta_objset;
 348         zapobj = dd->dd_phys->dd_props_zapobj;
 349         recvdstr = kmem_asprintf("%s%s", propname, ZPROP_RECVD_SUFFIX);
 350 
 351         version = spa_version(dd->dd_pool->dp_spa);
 352         if (version < SPA_VERSION_RECVD_PROPS) {
 353                 if (source & ZPROP_SRC_NONE)
 354                         source = ZPROP_SRC_NONE;
 355                 else if (source & ZPROP_SRC_RECEIVED)
 356                         source = ZPROP_SRC_LOCAL;
 357         }
 358 
 359         switch (source) {
 360         case ZPROP_SRC_NONE:
 361                 /* Revert to the received value, if any. */
 362                 err = zap_lookup(mos, zapobj, recvdstr, 8, 1,
 363                     &psa->psa_effective_value);
 364                 if (err == ENOENT)
 365                         psa->psa_effective_value = 0;
 366                 break;
 367         case ZPROP_SRC_LOCAL:
 368                 psa->psa_effective_value = *(uint64_t *)psa->psa_value;
 369                 break;
 370         case ZPROP_SRC_RECEIVED:
 371                 /*
 372                  * If there's no local setting, then the new received value will
 373                  * be the effective value.
 374                  */
 375                 err = zap_lookup(mos, zapobj, propname, 8, 1,
 376                     &psa->psa_effective_value);
 377                 if (err == ENOENT)
 378                         psa->psa_effective_value = *(uint64_t *)psa->psa_value;
 379                 break;
 380         case (ZPROP_SRC_NONE | ZPROP_SRC_RECEIVED):
 381                 /*
 382                  * We're clearing the received value, so the local setting (if
 383                  * it exists) remains the effective value.
 384                  */
 385                 err = zap_lookup(mos, zapobj, propname, 8, 1,
 386                     &psa->psa_effective_value);
 387                 if (err == ENOENT)
 388                         psa->psa_effective_value = 0;
 389                 break;
 390         default:
 391                 cmn_err(CE_PANIC, "unexpected property source: %d", source);
 392         }
 393 
 394         strfree(recvdstr);
 395 
 396         if (err == ENOENT)
 397                 return (0);
 398 
 399         return (err);
 400 }
 401 
 402 #ifdef  ZFS_DEBUG
 403 void
 404 dsl_prop_check_prediction(dsl_dir_t *dd, dsl_prop_setarg_t *psa)
 405 {
 406         zfs_prop_t prop = zfs_name_to_prop(psa->psa_name);
 407         uint64_t intval;
 408         char setpoint[MAXNAMELEN];
 409         uint64_t version = spa_version(dd->dd_pool->dp_spa);
 410         int err;
 411 
 412         if (version < SPA_VERSION_RECVD_PROPS) {
 413                 switch (prop) {
 414                 case ZFS_PROP_QUOTA:
 415                 case ZFS_PROP_RESERVATION:
 416                         return;
 417                 }
 418         }
 419 
 420         err = dsl_prop_get_dd(dd, psa->psa_name, 8, 1, &intval,
 421             setpoint, B_FALSE);
 422         if (err == 0 && intval != psa->psa_effective_value) {
 423                 cmn_err(CE_PANIC, "%s property, source: %x, "
 424                     "predicted effective value: %llu, "
 425                     "actual effective value: %llu (setpoint: %s)",
 426                     psa->psa_name, psa->psa_source,
 427                     (unsigned long long)psa->psa_effective_value,
 428                     (unsigned long long)intval, setpoint);
 429         }
 430 }
 431 #endif
 432 
 433 /*
 434  * Unregister this callback.  Return 0 on success, ENOENT if ddname is
 435  * invalid, ENOMSG if no matching callback registered.
 436  */
 437 int
 438 dsl_prop_unregister(dsl_dataset_t *ds, const char *propname,
 439     dsl_prop_changed_cb_t *callback, void *cbarg)
 440 {
 441         dsl_dir_t *dd = ds->ds_dir;
 442         dsl_prop_cb_record_t *cbr;
 443 
 444         mutex_enter(&dd->dd_lock);
 445         for (cbr = list_head(&dd->dd_prop_cbs);
 446             cbr; cbr = list_next(&dd->dd_prop_cbs, cbr)) {
 447                 if (cbr->cbr_ds == ds &&
 448                     cbr->cbr_func == callback &&
 449                     cbr->cbr_arg == cbarg &&
 450                     strcmp(cbr->cbr_propname, propname) == 0)
 451                         break;
 452         }
 453 
 454         if (cbr == NULL) {
 455                 mutex_exit(&dd->dd_lock);
 456                 return (ENOMSG);
 457         }
 458 
 459         list_remove(&dd->dd_prop_cbs, cbr);
 460         mutex_exit(&dd->dd_lock);
 461         kmem_free((void*)cbr->cbr_propname, strlen(cbr->cbr_propname)+1);
 462         kmem_free(cbr, sizeof (dsl_prop_cb_record_t));
 463 
 464         return (0);
 465 }
 466 
 467 /*
 468  * Return the number of callbacks that are registered for this dataset.
 469  */
 470 int
 471 dsl_prop_numcb(dsl_dataset_t *ds)
 472 {
 473         dsl_dir_t *dd = ds->ds_dir;
 474         dsl_prop_cb_record_t *cbr;
 475         int num = 0;
 476 
 477         mutex_enter(&dd->dd_lock);
 478         for (cbr = list_head(&dd->dd_prop_cbs);
 479             cbr; cbr = list_next(&dd->dd_prop_cbs, cbr)) {
 480                 if (cbr->cbr_ds == ds)
 481                         num++;
 482         }
 483         mutex_exit(&dd->dd_lock);
 484 
 485         return (num);
 486 }
 487 
 488 static void
 489 dsl_prop_changed_notify(dsl_pool_t *dp, uint64_t ddobj,
 490     const char *propname, uint64_t value, int first)
 491 {
 492         dsl_dir_t *dd;
 493         dsl_prop_cb_record_t *cbr;
 494         objset_t *mos = dp->dp_meta_objset;
 495         zap_cursor_t zc;
 496         zap_attribute_t *za;
 497         int err;
 498 
 499         ASSERT(RW_WRITE_HELD(&dp->dp_config_rwlock));
 500         err = dsl_dir_open_obj(dp, ddobj, NULL, FTAG, &dd);
 501         if (err)
 502                 return;
 503 
 504         if (!first) {
 505                 /*
 506                  * If the prop is set here, then this change is not
 507                  * being inherited here or below; stop the recursion.
 508                  */
 509                 err = zap_contains(mos, dd->dd_phys->dd_props_zapobj, propname);
 510                 if (err == 0) {
 511                         dsl_dir_close(dd, FTAG);
 512                         return;
 513                 }
 514                 ASSERT3U(err, ==, ENOENT);
 515         }
 516 
 517         mutex_enter(&dd->dd_lock);
 518         for (cbr = list_head(&dd->dd_prop_cbs); cbr;
 519             cbr = list_next(&dd->dd_prop_cbs, cbr)) {
 520                 uint64_t propobj = cbr->cbr_ds->ds_phys->ds_props_obj;
 521 
 522                 if (strcmp(cbr->cbr_propname, propname) != 0)
 523                         continue;
 524 
 525                 /*
 526                  * If the property is set on this ds, then it is not
 527                  * inherited here; don't call the callback.
 528                  */
 529                 if (propobj && 0 == zap_contains(mos, propobj, propname))
 530                         continue;
 531 
 532                 cbr->cbr_func(cbr->cbr_arg, value);
 533         }
 534         mutex_exit(&dd->dd_lock);
 535 
 536         za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
 537         for (zap_cursor_init(&zc, mos,
 538             dd->dd_phys->dd_child_dir_zapobj);
 539             zap_cursor_retrieve(&zc, za) == 0;
 540             zap_cursor_advance(&zc)) {
 541                 dsl_prop_changed_notify(dp, za->za_first_integer,
 542                     propname, value, FALSE);
 543         }
 544         kmem_free(za, sizeof (zap_attribute_t));
 545         zap_cursor_fini(&zc);
 546         dsl_dir_close(dd, FTAG);
 547 }
 548 
 549 void
 550 dsl_prop_set_sync(void *arg1, void *arg2, dmu_tx_t *tx)
 551 {
 552         dsl_dataset_t *ds = arg1;
 553         dsl_prop_setarg_t *psa = arg2;
 554         objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
 555         uint64_t zapobj, intval, dummy;
 556         int isint;
 557         char valbuf[32];
 558         char *valstr = NULL;
 559         char *inheritstr;
 560         char *recvdstr;
 561         char *tbuf = NULL;
 562         int err;
 563         uint64_t version = spa_version(ds->ds_dir->dd_pool->dp_spa);
 564         const char *propname = psa->psa_name;
 565         zprop_source_t source = psa->psa_source;
 566 
 567         isint = (dodefault(propname, 8, 1, &intval) == 0);
 568 
 569         if (ds->ds_phys != NULL && dsl_dataset_is_snapshot(ds)) {
 570                 ASSERT(version >= SPA_VERSION_SNAP_PROPS);
 571                 if (ds->ds_phys->ds_props_obj == 0) {
 572                         dmu_buf_will_dirty(ds->ds_dbuf, tx);
 573                         ds->ds_phys->ds_props_obj =
 574                             zap_create(mos,
 575                             DMU_OT_DSL_PROPS, DMU_OT_NONE, 0, tx);
 576                 }
 577                 zapobj = ds->ds_phys->ds_props_obj;
 578         } else {
 579                 zapobj = ds->ds_dir->dd_phys->dd_props_zapobj;
 580         }
 581 
 582         if (version < SPA_VERSION_RECVD_PROPS) {
 583                 zfs_prop_t prop = zfs_name_to_prop(propname);
 584                 if (prop == ZFS_PROP_QUOTA || prop == ZFS_PROP_RESERVATION)
 585                         return;
 586 
 587                 if (source & ZPROP_SRC_NONE)
 588                         source = ZPROP_SRC_NONE;
 589                 else if (source & ZPROP_SRC_RECEIVED)
 590                         source = ZPROP_SRC_LOCAL;
 591         }
 592 
 593         inheritstr = kmem_asprintf("%s%s", propname, ZPROP_INHERIT_SUFFIX);
 594         recvdstr = kmem_asprintf("%s%s", propname, ZPROP_RECVD_SUFFIX);
 595 
 596         switch (source) {
 597         case ZPROP_SRC_NONE:
 598                 /*
 599                  * revert to received value, if any (inherit -S)
 600                  * - remove propname
 601                  * - remove propname$inherit
 602                  */
 603                 err = zap_remove(mos, zapobj, propname, tx);
 604                 ASSERT(err == 0 || err == ENOENT);
 605                 err = zap_remove(mos, zapobj, inheritstr, tx);
 606                 ASSERT(err == 0 || err == ENOENT);
 607                 break;
 608         case ZPROP_SRC_LOCAL:
 609                 /*
 610                  * remove propname$inherit
 611                  * set propname -> value
 612                  */
 613                 err = zap_remove(mos, zapobj, inheritstr, tx);
 614                 ASSERT(err == 0 || err == ENOENT);
 615                 VERIFY(0 == zap_update(mos, zapobj, propname,
 616                     psa->psa_intsz, psa->psa_numints, psa->psa_value, tx));
 617                 break;
 618         case ZPROP_SRC_INHERITED:
 619                 /*
 620                  * explicitly inherit
 621                  * - remove propname
 622                  * - set propname$inherit
 623                  */
 624                 err = zap_remove(mos, zapobj, propname, tx);
 625                 ASSERT(err == 0 || err == ENOENT);
 626                 if (version >= SPA_VERSION_RECVD_PROPS &&
 627                     dsl_prop_get_ds(ds, ZPROP_HAS_RECVD, 8, 1, &dummy,
 628                     NULL) == 0) {
 629                         dummy = 0;
 630                         err = zap_update(mos, zapobj, inheritstr,
 631                             8, 1, &dummy, tx);
 632                         ASSERT(err == 0);
 633                 }
 634                 break;
 635         case ZPROP_SRC_RECEIVED:
 636                 /*
 637                  * set propname$recvd -> value
 638                  */
 639                 err = zap_update(mos, zapobj, recvdstr,
 640                     psa->psa_intsz, psa->psa_numints, psa->psa_value, tx);
 641                 ASSERT(err == 0);
 642                 break;
 643         case (ZPROP_SRC_NONE | ZPROP_SRC_LOCAL | ZPROP_SRC_RECEIVED):
 644                 /*
 645                  * clear local and received settings
 646                  * - remove propname
 647                  * - remove propname$inherit
 648                  * - remove propname$recvd
 649                  */
 650                 err = zap_remove(mos, zapobj, propname, tx);
 651                 ASSERT(err == 0 || err == ENOENT);
 652                 err = zap_remove(mos, zapobj, inheritstr, tx);
 653                 ASSERT(err == 0 || err == ENOENT);
 654                 /* FALLTHRU */
 655         case (ZPROP_SRC_NONE | ZPROP_SRC_RECEIVED):
 656                 /*
 657                  * remove propname$recvd
 658                  */
 659                 err = zap_remove(mos, zapobj, recvdstr, tx);
 660                 ASSERT(err == 0 || err == ENOENT);
 661                 break;
 662         default:
 663                 cmn_err(CE_PANIC, "unexpected property source: %d", source);
 664         }
 665 
 666         strfree(inheritstr);
 667         strfree(recvdstr);
 668 
 669         if (isint) {
 670                 VERIFY(0 == dsl_prop_get_ds(ds, propname, 8, 1, &intval, NULL));
 671 
 672                 if (ds->ds_phys != NULL && dsl_dataset_is_snapshot(ds)) {
 673                         dsl_prop_cb_record_t *cbr;
 674                         /*
 675                          * It's a snapshot; nothing can inherit this
 676                          * property, so just look for callbacks on this
 677                          * ds here.
 678                          */
 679                         mutex_enter(&ds->ds_dir->dd_lock);
 680                         for (cbr = list_head(&ds->ds_dir->dd_prop_cbs); cbr;
 681                             cbr = list_next(&ds->ds_dir->dd_prop_cbs, cbr)) {
 682                                 if (cbr->cbr_ds == ds &&
 683                                     strcmp(cbr->cbr_propname, propname) == 0)
 684                                         cbr->cbr_func(cbr->cbr_arg, intval);
 685                         }
 686                         mutex_exit(&ds->ds_dir->dd_lock);
 687                 } else {
 688                         dsl_prop_changed_notify(ds->ds_dir->dd_pool,
 689                             ds->ds_dir->dd_object, propname, intval, TRUE);
 690                 }
 691 
 692                 (void) snprintf(valbuf, sizeof (valbuf),
 693                     "%lld", (longlong_t)intval);
 694                 valstr = valbuf;
 695         } else {
 696                 if (source == ZPROP_SRC_LOCAL) {
 697                         valstr = (char *)psa->psa_value;
 698                 } else {
 699                         tbuf = kmem_alloc(ZAP_MAXVALUELEN, KM_SLEEP);
 700                         if (dsl_prop_get_ds(ds, propname, 1,
 701                             ZAP_MAXVALUELEN, tbuf, NULL) == 0)
 702                                 valstr = tbuf;
 703                 }
 704         }
 705 
 706         spa_history_log_internal_ds(ds, (source == ZPROP_SRC_NONE ||
 707             source == ZPROP_SRC_INHERITED) ? "inherit" : "set", tx,
 708             "%s=%s", propname, (valstr == NULL ? "" : valstr));
 709 
 710         if (tbuf != NULL)
 711                 kmem_free(tbuf, ZAP_MAXVALUELEN);
 712 }
 713 
 714 void
 715 dsl_props_set_sync(void *arg1, void *arg2, dmu_tx_t *tx)
 716 {
 717         dsl_dataset_t *ds = arg1;
 718         dsl_props_arg_t *pa = arg2;
 719         nvlist_t *props = pa->pa_props;
 720         dsl_prop_setarg_t psa;
 721         nvpair_t *elem = NULL;
 722 
 723         psa.psa_source = pa->pa_source;
 724 
 725         while ((elem = nvlist_next_nvpair(props, elem)) != NULL) {
 726                 nvpair_t *pair = elem;
 727 
 728                 psa.psa_name = nvpair_name(pair);
 729 
 730                 if (nvpair_type(pair) == DATA_TYPE_NVLIST) {
 731                         /*
 732                          * dsl_prop_get_all_impl() returns properties in this
 733                          * format.
 734                          */
 735                         nvlist_t *attrs;
 736                         VERIFY(nvpair_value_nvlist(pair, &attrs) == 0);
 737                         VERIFY(nvlist_lookup_nvpair(attrs, ZPROP_VALUE,
 738                             &pair) == 0);
 739                 }
 740 
 741                 if (nvpair_type(pair) == DATA_TYPE_STRING) {
 742                         VERIFY(nvpair_value_string(pair,
 743                             (char **)&psa.psa_value) == 0);
 744                         psa.psa_intsz = 1;
 745                         psa.psa_numints = strlen(psa.psa_value) + 1;
 746                 } else {
 747                         uint64_t intval;
 748                         VERIFY(nvpair_value_uint64(pair, &intval) == 0);
 749                         psa.psa_intsz = sizeof (intval);
 750                         psa.psa_numints = 1;
 751                         psa.psa_value = &intval;
 752                 }
 753                 dsl_prop_set_sync(ds, &psa, tx);
 754         }
 755 }
 756 
 757 int
 758 dsl_prop_set(const char *dsname, const char *propname, zprop_source_t source,
 759     int intsz, int numints, const void *buf)
 760 {
 761         dsl_dataset_t *ds;
 762         uint64_t version;
 763         int err;
 764         dsl_prop_setarg_t psa;
 765 
 766         /*
 767          * We must do these checks before we get to the syncfunc, since
 768          * it can't fail.
 769          */
 770         if (strlen(propname) >= ZAP_MAXNAMELEN)
 771                 return (ENAMETOOLONG);
 772 
 773         err = dsl_dataset_hold(dsname, FTAG, &ds);
 774         if (err)
 775                 return (err);
 776 
 777         version = spa_version(ds->ds_dir->dd_pool->dp_spa);
 778         if (intsz * numints >= (version < SPA_VERSION_STMF_PROP ?
 779             ZAP_OLDMAXVALUELEN : ZAP_MAXVALUELEN)) {
 780                 dsl_dataset_rele(ds, FTAG);
 781                 return (E2BIG);
 782         }
 783         if (dsl_dataset_is_snapshot(ds) &&
 784             version < SPA_VERSION_SNAP_PROPS) {
 785                 dsl_dataset_rele(ds, FTAG);
 786                 return (ENOTSUP);
 787         }
 788 
 789         psa.psa_name = propname;
 790         psa.psa_source = source;
 791         psa.psa_intsz = intsz;
 792         psa.psa_numints = numints;
 793         psa.psa_value = buf;
 794         psa.psa_effective_value = -1ULL;
 795 
 796         err = dsl_sync_task_do(ds->ds_dir->dd_pool,
 797             NULL, dsl_prop_set_sync, ds, &psa, 2);
 798 
 799         dsl_dataset_rele(ds, FTAG);
 800         return (err);
 801 }
 802 
 803 int
 804 dsl_props_set(const char *dsname, zprop_source_t source, nvlist_t *props)
 805 {
 806         dsl_dataset_t *ds;
 807         uint64_t version;
 808         nvpair_t *elem = NULL;
 809         dsl_props_arg_t pa;
 810         int err;
 811 
 812         if (err = dsl_dataset_hold(dsname, FTAG, &ds))
 813                 return (err);
 814         /*
 815          * Do these checks before the syncfunc, since it can't fail.
 816          */
 817         version = spa_version(ds->ds_dir->dd_pool->dp_spa);
 818         while ((elem = nvlist_next_nvpair(props, elem)) != NULL) {
 819                 if (strlen(nvpair_name(elem)) >= ZAP_MAXNAMELEN) {
 820                         dsl_dataset_rele(ds, FTAG);
 821                         return (ENAMETOOLONG);
 822                 }
 823                 if (nvpair_type(elem) == DATA_TYPE_STRING) {
 824                         char *valstr;
 825                         VERIFY(nvpair_value_string(elem, &valstr) == 0);
 826                         if (strlen(valstr) >= (version <
 827                             SPA_VERSION_STMF_PROP ?
 828                             ZAP_OLDMAXVALUELEN : ZAP_MAXVALUELEN)) {
 829                                 dsl_dataset_rele(ds, FTAG);
 830                                 return (E2BIG);
 831                         }
 832                 }
 833         }
 834 
 835         if (dsl_dataset_is_snapshot(ds) &&
 836             version < SPA_VERSION_SNAP_PROPS) {
 837                 dsl_dataset_rele(ds, FTAG);
 838                 return (ENOTSUP);
 839         }
 840 
 841         pa.pa_props = props;
 842         pa.pa_source = source;
 843 
 844         err = dsl_sync_task_do(ds->ds_dir->dd_pool,
 845             NULL, dsl_props_set_sync, ds, &pa, 2);
 846 
 847         dsl_dataset_rele(ds, FTAG);
 848         return (err);
 849 }
 850 
 851 typedef enum dsl_prop_getflags {
 852         DSL_PROP_GET_INHERITING = 0x1,  /* searching parent of target ds */
 853         DSL_PROP_GET_SNAPSHOT = 0x2,    /* snapshot dataset */
 854         DSL_PROP_GET_LOCAL = 0x4,       /* local properties */
 855         DSL_PROP_GET_RECEIVED = 0x8     /* received properties */
 856 } dsl_prop_getflags_t;
 857 
 858 static int
 859 dsl_prop_get_all_impl(objset_t *mos, uint64_t propobj,
 860     const char *setpoint, dsl_prop_getflags_t flags, nvlist_t *nv)
 861 {
 862         zap_cursor_t zc;
 863         zap_attribute_t za;
 864         int err = 0;
 865 
 866         for (zap_cursor_init(&zc, mos, propobj);
 867             (err = zap_cursor_retrieve(&zc, &za)) == 0;
 868             zap_cursor_advance(&zc)) {
 869                 nvlist_t *propval;
 870                 zfs_prop_t prop;
 871                 char buf[ZAP_MAXNAMELEN];
 872                 char *valstr;
 873                 const char *suffix;
 874                 const char *propname;
 875                 const char *source;
 876 
 877                 suffix = strchr(za.za_name, '$');
 878 
 879                 if (suffix == NULL) {
 880                         /*
 881                          * Skip local properties if we only want received
 882                          * properties.
 883                          */
 884                         if (flags & DSL_PROP_GET_RECEIVED)
 885                                 continue;
 886 
 887                         propname = za.za_name;
 888                         source = setpoint;
 889                 } else if (strcmp(suffix, ZPROP_INHERIT_SUFFIX) == 0) {
 890                         /* Skip explicitly inherited entries. */
 891                         continue;
 892                 } else if (strcmp(suffix, ZPROP_RECVD_SUFFIX) == 0) {
 893                         if (flags & DSL_PROP_GET_LOCAL)
 894                                 continue;
 895 
 896                         (void) strncpy(buf, za.za_name, (suffix - za.za_name));
 897                         buf[suffix - za.za_name] = '\0';
 898                         propname = buf;
 899 
 900                         if (!(flags & DSL_PROP_GET_RECEIVED)) {
 901                                 /* Skip if locally overridden. */
 902                                 err = zap_contains(mos, propobj, propname);
 903                                 if (err == 0)
 904                                         continue;
 905                                 if (err != ENOENT)
 906                                         break;
 907 
 908                                 /* Skip if explicitly inherited. */
 909                                 valstr = kmem_asprintf("%s%s", propname,
 910                                     ZPROP_INHERIT_SUFFIX);
 911                                 err = zap_contains(mos, propobj, valstr);
 912                                 strfree(valstr);
 913                                 if (err == 0)
 914                                         continue;
 915                                 if (err != ENOENT)
 916                                         break;
 917                         }
 918 
 919                         source = ((flags & DSL_PROP_GET_INHERITING) ?
 920                             setpoint : ZPROP_SOURCE_VAL_RECVD);
 921                 } else {
 922                         /*
 923                          * For backward compatibility, skip suffixes we don't
 924                          * recognize.
 925                          */
 926                         continue;
 927                 }
 928 
 929                 prop = zfs_name_to_prop(propname);
 930 
 931                 /* Skip non-inheritable properties. */
 932                 if ((flags & DSL_PROP_GET_INHERITING) && prop != ZPROP_INVAL &&
 933                     !zfs_prop_inheritable(prop))
 934                         continue;
 935 
 936                 /* Skip properties not valid for this type. */
 937                 if ((flags & DSL_PROP_GET_SNAPSHOT) && prop != ZPROP_INVAL &&
 938                     !zfs_prop_valid_for_type(prop, ZFS_TYPE_SNAPSHOT))
 939                         continue;
 940 
 941                 /* Skip properties already defined. */
 942                 if (nvlist_exists(nv, propname))
 943                         continue;
 944 
 945                 VERIFY(nvlist_alloc(&propval, NV_UNIQUE_NAME, KM_SLEEP) == 0);
 946                 if (za.za_integer_length == 1) {
 947                         /*
 948                          * String property
 949                          */
 950                         char *tmp = kmem_alloc(za.za_num_integers,
 951                             KM_SLEEP);
 952                         err = zap_lookup(mos, propobj,
 953                             za.za_name, 1, za.za_num_integers, tmp);
 954                         if (err != 0) {
 955                                 kmem_free(tmp, za.za_num_integers);
 956                                 break;
 957                         }
 958                         VERIFY(nvlist_add_string(propval, ZPROP_VALUE,
 959                             tmp) == 0);
 960                         kmem_free(tmp, za.za_num_integers);
 961                 } else {
 962                         /*
 963                          * Integer property
 964                          */
 965                         ASSERT(za.za_integer_length == 8);
 966                         (void) nvlist_add_uint64(propval, ZPROP_VALUE,
 967                             za.za_first_integer);
 968                 }
 969 
 970                 VERIFY(nvlist_add_string(propval, ZPROP_SOURCE, source) == 0);
 971                 VERIFY(nvlist_add_nvlist(nv, propname, propval) == 0);
 972                 nvlist_free(propval);
 973         }
 974         zap_cursor_fini(&zc);
 975         if (err == ENOENT)
 976                 err = 0;
 977         return (err);
 978 }
 979 
 980 /*
 981  * Iterate over all properties for this dataset and return them in an nvlist.
 982  */
 983 static int
 984 dsl_prop_get_all_ds(dsl_dataset_t *ds, nvlist_t **nvp,
 985     dsl_prop_getflags_t flags)
 986 {
 987         dsl_dir_t *dd = ds->ds_dir;
 988         dsl_pool_t *dp = dd->dd_pool;
 989         objset_t *mos = dp->dp_meta_objset;
 990         int err = 0;
 991         char setpoint[MAXNAMELEN];
 992 
 993         VERIFY(nvlist_alloc(nvp, NV_UNIQUE_NAME, KM_SLEEP) == 0);
 994 
 995         if (dsl_dataset_is_snapshot(ds))
 996                 flags |= DSL_PROP_GET_SNAPSHOT;
 997 
 998         rw_enter(&dp->dp_config_rwlock, RW_READER);
 999 
1000         if (ds->ds_phys->ds_props_obj != 0) {
1001                 ASSERT(flags & DSL_PROP_GET_SNAPSHOT);
1002                 dsl_dataset_name(ds, setpoint);
1003                 err = dsl_prop_get_all_impl(mos, ds->ds_phys->ds_props_obj,
1004                     setpoint, flags, *nvp);
1005                 if (err)
1006                         goto out;
1007         }
1008 
1009         for (; dd != NULL; dd = dd->dd_parent) {
1010                 if (dd != ds->ds_dir || (flags & DSL_PROP_GET_SNAPSHOT)) {
1011                         if (flags & (DSL_PROP_GET_LOCAL |
1012                             DSL_PROP_GET_RECEIVED))
1013                                 break;
1014                         flags |= DSL_PROP_GET_INHERITING;
1015                 }
1016                 dsl_dir_name(dd, setpoint);
1017                 err = dsl_prop_get_all_impl(mos, dd->dd_phys->dd_props_zapobj,
1018                     setpoint, flags, *nvp);
1019                 if (err)
1020                         break;
1021         }
1022 out:
1023         rw_exit(&dp->dp_config_rwlock);
1024         return (err);
1025 }
1026 
1027 boolean_t
1028 dsl_prop_get_hasrecvd(objset_t *os)
1029 {
1030         dsl_dataset_t *ds = os->os_dsl_dataset;
1031         int rc;
1032         uint64_t dummy;
1033 
1034         rw_enter(&ds->ds_dir->dd_pool->dp_config_rwlock, RW_READER);
1035         rc = dsl_prop_get_ds(ds, ZPROP_HAS_RECVD, 8, 1, &dummy, NULL);
1036         rw_exit(&ds->ds_dir->dd_pool->dp_config_rwlock);
1037         ASSERT(rc != 0 || spa_version(os->os_spa) >= SPA_VERSION_RECVD_PROPS);
1038         return (rc == 0);
1039 }
1040 
1041 static void
1042 dsl_prop_set_hasrecvd_impl(objset_t *os, zprop_source_t source)
1043 {
1044         dsl_dataset_t *ds = os->os_dsl_dataset;
1045         uint64_t dummy = 0;
1046         dsl_prop_setarg_t psa;
1047 
1048         if (spa_version(os->os_spa) < SPA_VERSION_RECVD_PROPS)
1049                 return;
1050 
1051         dsl_prop_setarg_init_uint64(&psa, ZPROP_HAS_RECVD, source, &dummy);
1052 
1053         (void) dsl_sync_task_do(ds->ds_dir->dd_pool, NULL,
1054             dsl_prop_set_sync, ds, &psa, 2);
1055 }
1056 
1057 /*
1058  * Call after successfully receiving properties to ensure that only the first
1059  * receive on or after SPA_VERSION_RECVD_PROPS blows away local properties.
1060  */
1061 void
1062 dsl_prop_set_hasrecvd(objset_t *os)
1063 {
1064         if (dsl_prop_get_hasrecvd(os)) {
1065                 ASSERT(spa_version(os->os_spa) >= SPA_VERSION_RECVD_PROPS);
1066                 return;
1067         }
1068         dsl_prop_set_hasrecvd_impl(os, ZPROP_SRC_LOCAL);
1069 }
1070 
1071 void
1072 dsl_prop_unset_hasrecvd(objset_t *os)
1073 {
1074         dsl_prop_set_hasrecvd_impl(os, ZPROP_SRC_NONE);
1075 }
1076 
1077 int
1078 dsl_prop_get_all(objset_t *os, nvlist_t **nvp)
1079 {
1080         return (dsl_prop_get_all_ds(os->os_dsl_dataset, nvp, 0));
1081 }
1082 
1083 int
1084 dsl_prop_get_received(objset_t *os, nvlist_t **nvp)
1085 {
1086         /*
1087          * Received properties are not distinguishable from local properties
1088          * until the dataset has received properties on or after
1089          * SPA_VERSION_RECVD_PROPS.
1090          */
1091         dsl_prop_getflags_t flags = (dsl_prop_get_hasrecvd(os) ?
1092             DSL_PROP_GET_RECEIVED : DSL_PROP_GET_LOCAL);
1093         return (dsl_prop_get_all_ds(os->os_dsl_dataset, nvp, flags));
1094 }
1095 
1096 void
1097 dsl_prop_nvlist_add_uint64(nvlist_t *nv, zfs_prop_t prop, uint64_t value)
1098 {
1099         nvlist_t *propval;
1100         const char *propname = zfs_prop_to_name(prop);
1101         uint64_t default_value;
1102 
1103         if (nvlist_lookup_nvlist(nv, propname, &propval) == 0) {
1104                 VERIFY(nvlist_add_uint64(propval, ZPROP_VALUE, value) == 0);
1105                 return;
1106         }
1107 
1108         VERIFY(nvlist_alloc(&propval, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1109         VERIFY(nvlist_add_uint64(propval, ZPROP_VALUE, value) == 0);
1110         /* Indicate the default source if we can. */
1111         if (dodefault(propname, 8, 1, &default_value) == 0 &&
1112             value == default_value) {
1113                 VERIFY(nvlist_add_string(propval, ZPROP_SOURCE, "") == 0);
1114         }
1115         VERIFY(nvlist_add_nvlist(nv, propname, propval) == 0);
1116         nvlist_free(propval);
1117 }
1118 
1119 void
1120 dsl_prop_nvlist_add_string(nvlist_t *nv, zfs_prop_t prop, const char *value)
1121 {
1122         nvlist_t *propval;
1123         const char *propname = zfs_prop_to_name(prop);
1124 
1125         if (nvlist_lookup_nvlist(nv, propname, &propval) == 0) {
1126                 VERIFY(nvlist_add_string(propval, ZPROP_VALUE, value) == 0);
1127                 return;
1128         }
1129 
1130         VERIFY(nvlist_alloc(&propval, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1131         VERIFY(nvlist_add_string(propval, ZPROP_VALUE, value) == 0);
1132         VERIFY(nvlist_add_nvlist(nv, propname, propval) == 0);
1133         nvlist_free(propval);
1134 }