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) 2013 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 (SET_ERROR(ENOENT));
  56 
  57         if (zfs_prop_get_type(prop) == PROP_TYPE_STRING) {
  58                 if (intsz != 1)
  59                         return (SET_ERROR(EOVERFLOW));
  60                 (void) strncpy(buf, zfs_prop_default_string(prop),
  61                     numints);
  62         } else {
  63                 if (intsz != 8 || numints < 1)
  64                         return (SET_ERROR(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(dsl_pool_config_held(dd->dd_pool));
  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                 if (dd != target || snapshot) {
 101                         if (!inheritable)
 102                                 break;
 103                         inheriting = B_TRUE;
 104                 }
 105 
 106                 /* Check for a local value. */
 107                 err = zap_lookup(mos, dd->dd_phys->dd_props_zapobj, propname,
 108                     intsz, numints, buf);
 109                 if (err != ENOENT) {
 110                         if (setpoint != NULL && err == 0)
 111                                 dsl_dir_name(dd, setpoint);
 112                         break;
 113                 }
 114 
 115                 /*
 116                  * Skip the check for a received value if there is an explicit
 117                  * inheritance entry.
 118                  */
 119                 err = zap_contains(mos, dd->dd_phys->dd_props_zapobj,
 120                     inheritstr);
 121                 if (err != 0 && err != ENOENT)
 122                         break;
 123 
 124                 if (err == ENOENT) {
 125                         /* Check for a received value. */
 126                         err = zap_lookup(mos, dd->dd_phys->dd_props_zapobj,
 127                             recvdstr, intsz, numints, buf);
 128                         if (err != ENOENT) {
 129                                 if (setpoint != NULL && err == 0) {
 130                                         if (inheriting) {
 131                                                 dsl_dir_name(dd, setpoint);
 132                                         } else {
 133                                                 (void) strcpy(setpoint,
 134                                                     ZPROP_SOURCE_VAL_RECVD);
 135                                         }
 136                                 }
 137                                 break;
 138                         }
 139                 }
 140 
 141                 /*
 142                  * If we found an explicit inheritance entry, err is zero even
 143                  * though we haven't yet found the value, so reinitializing err
 144                  * at the end of the loop (instead of at the beginning) ensures
 145                  * that err has a valid post-loop value.
 146                  */
 147                 err = SET_ERROR(ENOENT);
 148         }
 149 
 150         if (err == ENOENT)
 151                 err = dodefault(propname, intsz, numints, buf);
 152 
 153         strfree(inheritstr);
 154         strfree(recvdstr);
 155 
 156         return (err);
 157 }
 158 
 159 int
 160 dsl_prop_get_ds(dsl_dataset_t *ds, const char *propname,
 161     int intsz, int numints, void *buf, char *setpoint)
 162 {
 163         zfs_prop_t prop = zfs_name_to_prop(propname);
 164         boolean_t inheritable;
 165         boolean_t snapshot;
 166         uint64_t zapobj;
 167 
 168         ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool));
 169         inheritable = (prop == ZPROP_INVAL || zfs_prop_inheritable(prop));
 170         snapshot = (DS_HAS_PHYS(ds) && dsl_dataset_is_snapshot(ds));
 171         zapobj = (DS_HAS_PHYS(ds) ? ds->ds_phys->ds_props_obj : 0);
 172 
 173         if (zapobj != 0) {
 174                 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
 175                 int err;
 176 
 177                 ASSERT(snapshot);
 178 
 179                 /* Check for a local value. */
 180                 err = zap_lookup(mos, zapobj, propname, intsz, numints, buf);
 181                 if (err != ENOENT) {
 182                         if (setpoint != NULL && err == 0)
 183                                 dsl_dataset_name(ds, setpoint);
 184                         return (err);
 185                 }
 186 
 187                 /*
 188                  * Skip the check for a received value if there is an explicit
 189                  * inheritance entry.
 190                  */
 191                 if (inheritable) {
 192                         char *inheritstr = kmem_asprintf("%s%s", propname,
 193                             ZPROP_INHERIT_SUFFIX);
 194                         err = zap_contains(mos, zapobj, inheritstr);
 195                         strfree(inheritstr);
 196                         if (err != 0 && err != ENOENT)
 197                                 return (err);
 198                 }
 199 
 200                 if (err == ENOENT) {
 201                         /* Check for a received value. */
 202                         char *recvdstr = kmem_asprintf("%s%s", propname,
 203                             ZPROP_RECVD_SUFFIX);
 204                         err = zap_lookup(mos, zapobj, recvdstr,
 205                             intsz, numints, buf);
 206                         strfree(recvdstr);
 207                         if (err != ENOENT) {
 208                                 if (setpoint != NULL && err == 0)
 209                                         (void) strcpy(setpoint,
 210                                             ZPROP_SOURCE_VAL_RECVD);
 211                                 return (err);
 212                         }
 213                 }
 214         }
 215 
 216         return (dsl_prop_get_dd(ds->ds_dir, propname,
 217             intsz, numints, buf, setpoint, snapshot));
 218 }
 219 
 220 /*
 221  * Register interest in the named property.  We'll call the callback
 222  * once to notify it of the current property value, and again each time
 223  * the property changes, until this callback is unregistered.
 224  *
 225  * Return 0 on success, errno if the prop is not an integer value.
 226  */
 227 int
 228 dsl_prop_register(dsl_dataset_t *ds, const char *propname,
 229     dsl_prop_changed_cb_t *callback, void *cbarg)
 230 {
 231         dsl_dir_t *dd = ds->ds_dir;
 232         dsl_pool_t *dp = dd->dd_pool;
 233         uint64_t value;
 234         dsl_prop_cb_record_t *cbr;
 235         int err;
 236 
 237         ASSERT(dsl_pool_config_held(dp));
 238 
 239         err = dsl_prop_get_int_ds(ds, propname, &value);
 240         if (err != 0)
 241                 return (err);
 242 
 243         cbr = kmem_alloc(sizeof (dsl_prop_cb_record_t), KM_SLEEP);
 244         cbr->cbr_ds = ds;
 245         cbr->cbr_propname = kmem_alloc(strlen(propname)+1, KM_SLEEP);
 246         (void) strcpy((char *)cbr->cbr_propname, propname);
 247         cbr->cbr_func = callback;
 248         cbr->cbr_arg = cbarg;
 249         mutex_enter(&dd->dd_lock);
 250         list_insert_head(&dd->dd_prop_cbs, cbr);
 251         mutex_exit(&dd->dd_lock);
 252 
 253         cbr->cbr_func(cbr->cbr_arg, value);
 254         return (0);
 255 }
 256 
 257 int
 258 dsl_prop_get(const char *dsname, const char *propname,
 259     int intsz, int numints, void *buf, char *setpoint)
 260 {
 261         objset_t *os;
 262         int error;
 263 
 264         error = dmu_objset_hold(dsname, FTAG, &os);
 265         if (error != 0)
 266                 return (error);
 267 
 268         error = dsl_prop_get_ds(dmu_objset_ds(os), propname,
 269             intsz, numints, buf, setpoint);
 270 
 271         dmu_objset_rele(os, FTAG);
 272         return (error);
 273 }
 274 
 275 /*
 276  * Get the current property value.  It may have changed by the time this
 277  * function returns, so it is NOT safe to follow up with
 278  * dsl_prop_register() and assume that the value has not changed in
 279  * between.
 280  *
 281  * Return 0 on success, ENOENT if ddname is invalid.
 282  */
 283 int
 284 dsl_prop_get_integer(const char *ddname, const char *propname,
 285     uint64_t *valuep, char *setpoint)
 286 {
 287         return (dsl_prop_get(ddname, propname, 8, 1, valuep, setpoint));
 288 }
 289 
 290 int
 291 dsl_prop_get_int_ds(dsl_dataset_t *ds, const char *propname,
 292     uint64_t *valuep)
 293 {
 294         return (dsl_prop_get_ds(ds, propname, 8, 1, valuep, NULL));
 295 }
 296 
 297 /*
 298  * Predict the effective value of the given special property if it were set with
 299  * the given value and source. This is not a general purpose function. It exists
 300  * only to handle the special requirements of the quota and reservation
 301  * properties. The fact that these properties are non-inheritable greatly
 302  * simplifies the prediction logic.
 303  *
 304  * Returns 0 on success, a positive error code on failure, or -1 if called with
 305  * a property not handled by this function.
 306  */
 307 int
 308 dsl_prop_predict(dsl_dir_t *dd, const char *propname,
 309     zprop_source_t source, uint64_t value, uint64_t *newvalp)
 310 {
 311         zfs_prop_t prop = zfs_name_to_prop(propname);
 312         objset_t *mos;
 313         uint64_t zapobj;
 314         uint64_t version;
 315         char *recvdstr;
 316         int err = 0;
 317 
 318         switch (prop) {
 319         case ZFS_PROP_QUOTA:
 320         case ZFS_PROP_RESERVATION:
 321         case ZFS_PROP_REFQUOTA:
 322         case ZFS_PROP_REFRESERVATION:
 323                 break;
 324         default:
 325                 return (-1);
 326         }
 327 
 328         mos = dd->dd_pool->dp_meta_objset;
 329         zapobj = dd->dd_phys->dd_props_zapobj;
 330         recvdstr = kmem_asprintf("%s%s", propname, ZPROP_RECVD_SUFFIX);
 331 
 332         version = spa_version(dd->dd_pool->dp_spa);
 333         if (version < SPA_VERSION_RECVD_PROPS) {
 334                 if (source & ZPROP_SRC_NONE)
 335                         source = ZPROP_SRC_NONE;
 336                 else if (source & ZPROP_SRC_RECEIVED)
 337                         source = ZPROP_SRC_LOCAL;
 338         }
 339 
 340         switch (source) {
 341         case ZPROP_SRC_NONE:
 342                 /* Revert to the received value, if any. */
 343                 err = zap_lookup(mos, zapobj, recvdstr, 8, 1, newvalp);
 344                 if (err == ENOENT)
 345                         *newvalp = 0;
 346                 break;
 347         case ZPROP_SRC_LOCAL:
 348                 *newvalp = value;
 349                 break;
 350         case ZPROP_SRC_RECEIVED:
 351                 /*
 352                  * If there's no local setting, then the new received value will
 353                  * be the effective value.
 354                  */
 355                 err = zap_lookup(mos, zapobj, propname, 8, 1, newvalp);
 356                 if (err == ENOENT)
 357                         *newvalp = value;
 358                 break;
 359         case (ZPROP_SRC_NONE | ZPROP_SRC_RECEIVED):
 360                 /*
 361                  * We're clearing the received value, so the local setting (if
 362                  * it exists) remains the effective value.
 363                  */
 364                 err = zap_lookup(mos, zapobj, propname, 8, 1, newvalp);
 365                 if (err == ENOENT)
 366                         *newvalp = 0;
 367                 break;
 368         default:
 369                 panic("unexpected property source: %d", source);
 370         }
 371 
 372         strfree(recvdstr);
 373 
 374         if (err == ENOENT)
 375                 return (0);
 376 
 377         return (err);
 378 }
 379 
 380 /*
 381  * Unregister this callback.  Return 0 on success, ENOENT if ddname is
 382  * invalid, ENOMSG if no matching callback registered.
 383  */
 384 int
 385 dsl_prop_unregister(dsl_dataset_t *ds, const char *propname,
 386     dsl_prop_changed_cb_t *callback, void *cbarg)
 387 {
 388         dsl_dir_t *dd = ds->ds_dir;
 389         dsl_prop_cb_record_t *cbr;
 390 
 391         mutex_enter(&dd->dd_lock);
 392         for (cbr = list_head(&dd->dd_prop_cbs);
 393             cbr; cbr = list_next(&dd->dd_prop_cbs, cbr)) {
 394                 if (cbr->cbr_ds == ds &&
 395                     cbr->cbr_func == callback &&
 396                     cbr->cbr_arg == cbarg &&
 397                     strcmp(cbr->cbr_propname, propname) == 0)
 398                         break;
 399         }
 400 
 401         if (cbr == NULL) {
 402                 mutex_exit(&dd->dd_lock);
 403                 return (SET_ERROR(ENOMSG));
 404         }
 405 
 406         list_remove(&dd->dd_prop_cbs, cbr);
 407         mutex_exit(&dd->dd_lock);
 408         kmem_free((void*)cbr->cbr_propname, strlen(cbr->cbr_propname)+1);
 409         kmem_free(cbr, sizeof (dsl_prop_cb_record_t));
 410 
 411         return (0);
 412 }
 413 
 414 boolean_t
 415 dsl_prop_hascb(dsl_dataset_t *ds)
 416 {
 417         dsl_dir_t *dd = ds->ds_dir;
 418         boolean_t rv = B_FALSE;
 419         dsl_prop_cb_record_t *cbr;
 420 
 421         mutex_enter(&dd->dd_lock);
 422         for (cbr = list_head(&dd->dd_prop_cbs); cbr;
 423             cbr = list_next(&dd->dd_prop_cbs, cbr)) {
 424                 if (cbr->cbr_ds == ds) {
 425                         rv = B_TRUE;
 426                         break;
 427                 }
 428         }
 429         mutex_exit(&dd->dd_lock);
 430         return (rv);
 431 }
 432 
 433 /* ARGSUSED */
 434 static int
 435 dsl_prop_notify_all_cb(dsl_pool_t *dp, dsl_dataset_t *ds, void *arg)
 436 {
 437         dsl_dir_t *dd = ds->ds_dir;
 438         dsl_prop_cb_record_t *cbr;
 439 
 440         mutex_enter(&dd->dd_lock);
 441         for (cbr = list_head(&dd->dd_prop_cbs); cbr;
 442             cbr = list_next(&dd->dd_prop_cbs, cbr)) {
 443                 uint64_t value;
 444 
 445                 if (dsl_prop_get_ds(cbr->cbr_ds, cbr->cbr_propname,
 446                     sizeof (value), 1, &value, NULL) == 0)
 447                         cbr->cbr_func(cbr->cbr_arg, value);
 448         }
 449         mutex_exit(&dd->dd_lock);
 450 
 451         return (0);
 452 }
 453 
 454 /*
 455  * Update all property values for ddobj & its descendants.  This is used
 456  * when renaming the dir.
 457  */
 458 void
 459 dsl_prop_notify_all(dsl_dir_t *dd)
 460 {
 461         dsl_pool_t *dp = dd->dd_pool;
 462         ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock));
 463         (void) dmu_objset_find_dp(dp, dd->dd_object, dsl_prop_notify_all_cb,
 464             NULL, DS_FIND_CHILDREN);
 465 }
 466 
 467 static void
 468 dsl_prop_changed_notify(dsl_pool_t *dp, uint64_t ddobj,
 469     const char *propname, uint64_t value, int first)
 470 {
 471         dsl_dir_t *dd;
 472         dsl_prop_cb_record_t *cbr;
 473         objset_t *mos = dp->dp_meta_objset;
 474         zap_cursor_t zc;
 475         zap_attribute_t *za;
 476         int err;
 477 
 478         ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock));
 479         err = dsl_dir_hold_obj(dp, ddobj, NULL, FTAG, &dd);
 480         if (err)
 481                 return;
 482 
 483         if (!first) {
 484                 /*
 485                  * If the prop is set here, then this change is not
 486                  * being inherited here or below; stop the recursion.
 487                  */
 488                 err = zap_contains(mos, dd->dd_phys->dd_props_zapobj, propname);
 489                 if (err == 0) {
 490                         dsl_dir_rele(dd, FTAG);
 491                         return;
 492                 }
 493                 ASSERT3U(err, ==, ENOENT);
 494         }
 495 
 496         mutex_enter(&dd->dd_lock);
 497         for (cbr = list_head(&dd->dd_prop_cbs); cbr;
 498             cbr = list_next(&dd->dd_prop_cbs, cbr)) {
 499                 uint64_t propobj = cbr->cbr_ds->ds_phys->ds_props_obj;
 500 
 501                 if (strcmp(cbr->cbr_propname, propname) != 0)
 502                         continue;
 503 
 504                 /*
 505                  * If the property is set on this ds, then it is not
 506                  * inherited here; don't call the callback.
 507                  */
 508                 if (propobj && 0 == zap_contains(mos, propobj, propname))
 509                         continue;
 510 
 511                 cbr->cbr_func(cbr->cbr_arg, value);
 512         }
 513         mutex_exit(&dd->dd_lock);
 514 
 515         za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
 516         for (zap_cursor_init(&zc, mos,
 517             dd->dd_phys->dd_child_dir_zapobj);
 518             zap_cursor_retrieve(&zc, za) == 0;
 519             zap_cursor_advance(&zc)) {
 520                 dsl_prop_changed_notify(dp, za->za_first_integer,
 521                     propname, value, FALSE);
 522         }
 523         kmem_free(za, sizeof (zap_attribute_t));
 524         zap_cursor_fini(&zc);
 525         dsl_dir_rele(dd, FTAG);
 526 }
 527 
 528 void
 529 dsl_prop_set_sync_impl(dsl_dataset_t *ds, const char *propname,
 530     zprop_source_t source, int intsz, int numints, const void *value,
 531     dmu_tx_t *tx)
 532 {
 533         objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
 534         uint64_t zapobj, intval, dummy;
 535         int isint;
 536         char valbuf[32];
 537         const char *valstr = NULL;
 538         char *inheritstr;
 539         char *recvdstr;
 540         char *tbuf = NULL;
 541         int err;
 542         uint64_t version = spa_version(ds->ds_dir->dd_pool->dp_spa);
 543 
 544         isint = (dodefault(propname, 8, 1, &intval) == 0);
 545 
 546         if (DS_HAS_PHYS(ds) && dsl_dataset_is_snapshot(ds)) {
 547                 ASSERT(version >= SPA_VERSION_SNAP_PROPS);
 548                 if (ds->ds_phys->ds_props_obj == 0) {
 549                         dmu_buf_will_dirty(ds->ds_dbuf, tx);
 550                         ds->ds_phys->ds_props_obj =
 551                             zap_create(mos,
 552                             DMU_OT_DSL_PROPS, DMU_OT_NONE, 0, tx);
 553                 }
 554                 zapobj = ds->ds_phys->ds_props_obj;
 555         } else {
 556                 zapobj = ds->ds_dir->dd_phys->dd_props_zapobj;
 557         }
 558 
 559         if (version < SPA_VERSION_RECVD_PROPS) {
 560                 zfs_prop_t prop = zfs_name_to_prop(propname);
 561                 if (prop == ZFS_PROP_QUOTA || prop == ZFS_PROP_RESERVATION)
 562                         return;
 563 
 564                 if (source & ZPROP_SRC_NONE)
 565                         source = ZPROP_SRC_NONE;
 566                 else if (source & ZPROP_SRC_RECEIVED)
 567                         source = ZPROP_SRC_LOCAL;
 568         }
 569 
 570         inheritstr = kmem_asprintf("%s%s", propname, ZPROP_INHERIT_SUFFIX);
 571         recvdstr = kmem_asprintf("%s%s", propname, ZPROP_RECVD_SUFFIX);
 572 
 573         switch (source) {
 574         case ZPROP_SRC_NONE:
 575                 /*
 576                  * revert to received value, if any (inherit -S)
 577                  * - remove propname
 578                  * - remove propname$inherit
 579                  */
 580                 err = zap_remove(mos, zapobj, propname, tx);
 581                 ASSERT(err == 0 || err == ENOENT);
 582                 err = zap_remove(mos, zapobj, inheritstr, tx);
 583                 ASSERT(err == 0 || err == ENOENT);
 584                 break;
 585         case ZPROP_SRC_LOCAL:
 586                 /*
 587                  * remove propname$inherit
 588                  * set propname -> value
 589                  */
 590                 err = zap_remove(mos, zapobj, inheritstr, tx);
 591                 ASSERT(err == 0 || err == ENOENT);
 592                 VERIFY0(zap_update(mos, zapobj, propname,
 593                     intsz, numints, value, tx));
 594                 break;
 595         case ZPROP_SRC_INHERITED:
 596                 /*
 597                  * explicitly inherit
 598                  * - remove propname
 599                  * - set propname$inherit
 600                  */
 601                 err = zap_remove(mos, zapobj, propname, tx);
 602                 ASSERT(err == 0 || err == ENOENT);
 603                 if (version >= SPA_VERSION_RECVD_PROPS &&
 604                     dsl_prop_get_int_ds(ds, ZPROP_HAS_RECVD, &dummy) == 0) {
 605                         dummy = 0;
 606                         VERIFY0(zap_update(mos, zapobj, inheritstr,
 607                             8, 1, &dummy, tx));
 608                 }
 609                 break;
 610         case ZPROP_SRC_RECEIVED:
 611                 /*
 612                  * set propname$recvd -> value
 613                  */
 614                 err = zap_update(mos, zapobj, recvdstr,
 615                     intsz, numints, value, tx);
 616                 ASSERT(err == 0);
 617                 break;
 618         case (ZPROP_SRC_NONE | ZPROP_SRC_LOCAL | ZPROP_SRC_RECEIVED):
 619                 /*
 620                  * clear local and received settings
 621                  * - remove propname
 622                  * - remove propname$inherit
 623                  * - remove propname$recvd
 624                  */
 625                 err = zap_remove(mos, zapobj, propname, tx);
 626                 ASSERT(err == 0 || err == ENOENT);
 627                 err = zap_remove(mos, zapobj, inheritstr, tx);
 628                 ASSERT(err == 0 || err == ENOENT);
 629                 /* FALLTHRU */
 630         case (ZPROP_SRC_NONE | ZPROP_SRC_RECEIVED):
 631                 /*
 632                  * remove propname$recvd
 633                  */
 634                 err = zap_remove(mos, zapobj, recvdstr, tx);
 635                 ASSERT(err == 0 || err == ENOENT);
 636                 break;
 637         default:
 638                 cmn_err(CE_PANIC, "unexpected property source: %d", source);
 639         }
 640 
 641         strfree(inheritstr);
 642         strfree(recvdstr);
 643 
 644         if (isint) {
 645                 VERIFY0(dsl_prop_get_int_ds(ds, propname, &intval));
 646 
 647                 if (DS_HAS_PHYS(ds) && dsl_dataset_is_snapshot(ds)) {
 648                         dsl_prop_cb_record_t *cbr;
 649                         /*
 650                          * It's a snapshot; nothing can inherit this
 651                          * property, so just look for callbacks on this
 652                          * ds here.
 653                          */
 654                         mutex_enter(&ds->ds_dir->dd_lock);
 655                         for (cbr = list_head(&ds->ds_dir->dd_prop_cbs); cbr;
 656                             cbr = list_next(&ds->ds_dir->dd_prop_cbs, cbr)) {
 657                                 if (cbr->cbr_ds == ds &&
 658                                     strcmp(cbr->cbr_propname, propname) == 0)
 659                                         cbr->cbr_func(cbr->cbr_arg, intval);
 660                         }
 661                         mutex_exit(&ds->ds_dir->dd_lock);
 662                 } else {
 663                         dsl_prop_changed_notify(ds->ds_dir->dd_pool,
 664                             ds->ds_dir->dd_object, propname, intval, TRUE);
 665                 }
 666 
 667                 (void) snprintf(valbuf, sizeof (valbuf),
 668                     "%lld", (longlong_t)intval);
 669                 valstr = valbuf;
 670         } else {
 671                 if (source == ZPROP_SRC_LOCAL) {
 672                         valstr = value;
 673                 } else {
 674                         tbuf = kmem_alloc(ZAP_MAXVALUELEN, KM_SLEEP);
 675                         if (dsl_prop_get_ds(ds, propname, 1,
 676                             ZAP_MAXVALUELEN, tbuf, NULL) == 0)
 677                                 valstr = tbuf;
 678                 }
 679         }
 680 
 681         spa_history_log_internal_ds(ds, (source == ZPROP_SRC_NONE ||
 682             source == ZPROP_SRC_INHERITED) ? "inherit" : "set", tx,
 683             "%s=%s", propname, (valstr == NULL ? "" : valstr));
 684 
 685         if (tbuf != NULL)
 686                 kmem_free(tbuf, ZAP_MAXVALUELEN);
 687 }
 688 
 689 int
 690 dsl_prop_set_int(const char *dsname, const char *propname,
 691     zprop_source_t source, uint64_t value)
 692 {
 693         nvlist_t *nvl = fnvlist_alloc();
 694         int error;
 695 
 696         fnvlist_add_uint64(nvl, propname, value);
 697         error = dsl_props_set(dsname, source, nvl);
 698         fnvlist_free(nvl);
 699         return (error);
 700 }
 701 
 702 int
 703 dsl_prop_set_string(const char *dsname, const char *propname,
 704     zprop_source_t source, const char *value)
 705 {
 706         nvlist_t *nvl = fnvlist_alloc();
 707         int error;
 708 
 709         fnvlist_add_string(nvl, propname, value);
 710         error = dsl_props_set(dsname, source, nvl);
 711         fnvlist_free(nvl);
 712         return (error);
 713 }
 714 
 715 int
 716 dsl_prop_inherit(const char *dsname, const char *propname,
 717     zprop_source_t source)
 718 {
 719         nvlist_t *nvl = fnvlist_alloc();
 720         int error;
 721 
 722         fnvlist_add_boolean(nvl, propname);
 723         error = dsl_props_set(dsname, source, nvl);
 724         fnvlist_free(nvl);
 725         return (error);
 726 }
 727 
 728 typedef struct dsl_props_set_arg {
 729         const char *dpsa_dsname;
 730         zprop_source_t dpsa_source;
 731         nvlist_t *dpsa_props;
 732 } dsl_props_set_arg_t;
 733 
 734 static int
 735 dsl_props_set_check(void *arg, dmu_tx_t *tx)
 736 {
 737         dsl_props_set_arg_t *dpsa = arg;
 738         dsl_pool_t *dp = dmu_tx_pool(tx);
 739         dsl_dataset_t *ds;
 740         uint64_t version;
 741         nvpair_t *elem = NULL;
 742         int err;
 743 
 744         err = dsl_dataset_hold(dp, dpsa->dpsa_dsname, FTAG, &ds);
 745         if (err != 0)
 746                 return (err);
 747 
 748         version = spa_version(ds->ds_dir->dd_pool->dp_spa);
 749         while ((elem = nvlist_next_nvpair(dpsa->dpsa_props, elem)) != NULL) {
 750                 if (strlen(nvpair_name(elem)) >= ZAP_MAXNAMELEN) {
 751                         dsl_dataset_rele(ds, FTAG);
 752                         return (SET_ERROR(ENAMETOOLONG));
 753                 }
 754                 if (nvpair_type(elem) == DATA_TYPE_STRING) {
 755                         char *valstr = fnvpair_value_string(elem);
 756                         if (strlen(valstr) >= (version <
 757                             SPA_VERSION_STMF_PROP ?
 758                             ZAP_OLDMAXVALUELEN : ZAP_MAXVALUELEN)) {
 759                                 dsl_dataset_rele(ds, FTAG);
 760                                 return (E2BIG);
 761                         }
 762                 }
 763         }
 764 
 765         if (dsl_dataset_is_snapshot(ds) && version < SPA_VERSION_SNAP_PROPS) {
 766                 dsl_dataset_rele(ds, FTAG);
 767                 return (SET_ERROR(ENOTSUP));
 768         }
 769         dsl_dataset_rele(ds, FTAG);
 770         return (0);
 771 }
 772 
 773 void
 774 dsl_props_set_sync_impl(dsl_dataset_t *ds, zprop_source_t source,
 775     nvlist_t *props, dmu_tx_t *tx)
 776 {
 777         nvpair_t *elem = NULL;
 778 
 779         while ((elem = nvlist_next_nvpair(props, elem)) != NULL) {
 780                 nvpair_t *pair = elem;
 781 
 782                 if (nvpair_type(pair) == DATA_TYPE_NVLIST) {
 783                         /*
 784                          * dsl_prop_get_all_impl() returns properties in this
 785                          * format.
 786                          */
 787                         nvlist_t *attrs = fnvpair_value_nvlist(pair);
 788                         pair = fnvlist_lookup_nvpair(attrs, ZPROP_VALUE);
 789                 }
 790 
 791                 if (nvpair_type(pair) == DATA_TYPE_STRING) {
 792                         const char *value = fnvpair_value_string(pair);
 793                         dsl_prop_set_sync_impl(ds, nvpair_name(pair),
 794                             source, 1, strlen(value) + 1, value, tx);
 795                 } else if (nvpair_type(pair) == DATA_TYPE_UINT64) {
 796                         uint64_t intval = fnvpair_value_uint64(pair);
 797                         dsl_prop_set_sync_impl(ds, nvpair_name(pair),
 798                             source, sizeof (intval), 1, &intval, tx);
 799                 } else if (nvpair_type(pair) == DATA_TYPE_BOOLEAN) {
 800                         dsl_prop_set_sync_impl(ds, nvpair_name(pair),
 801                             source, 0, 0, NULL, tx);
 802                 } else {
 803                         panic("invalid nvpair type");
 804                 }
 805         }
 806 }
 807 
 808 static void
 809 dsl_props_set_sync(void *arg, dmu_tx_t *tx)
 810 {
 811         dsl_props_set_arg_t *dpsa = arg;
 812         dsl_pool_t *dp = dmu_tx_pool(tx);
 813         dsl_dataset_t *ds;
 814 
 815         VERIFY0(dsl_dataset_hold(dp, dpsa->dpsa_dsname, FTAG, &ds));
 816         dsl_props_set_sync_impl(ds, dpsa->dpsa_source, dpsa->dpsa_props, tx);
 817         dsl_dataset_rele(ds, FTAG);
 818 }
 819 
 820 /*
 821  * All-or-nothing; if any prop can't be set, nothing will be modified.
 822  */
 823 int
 824 dsl_props_set(const char *dsname, zprop_source_t source, nvlist_t *props)
 825 {
 826         dsl_props_set_arg_t dpsa;
 827         int nblks = 0;
 828 
 829         dpsa.dpsa_dsname = dsname;
 830         dpsa.dpsa_source = source;
 831         dpsa.dpsa_props = props;
 832 
 833         /*
 834          * If the source includes NONE, then we will only be removing entries
 835          * from the ZAP object.  In that case don't check for ENOSPC.
 836          */
 837         if ((source & ZPROP_SRC_NONE) == 0)
 838                 nblks = 2 * fnvlist_num_pairs(props);
 839 
 840         return (dsl_sync_task(dsname, dsl_props_set_check, dsl_props_set_sync,
 841             &dpsa, nblks));
 842 }
 843 
 844 typedef enum dsl_prop_getflags {
 845         DSL_PROP_GET_INHERITING = 0x1,  /* searching parent of target ds */
 846         DSL_PROP_GET_SNAPSHOT = 0x2,    /* snapshot dataset */
 847         DSL_PROP_GET_LOCAL = 0x4,       /* local properties */
 848         DSL_PROP_GET_RECEIVED = 0x8     /* received properties */
 849 } dsl_prop_getflags_t;
 850 
 851 static int
 852 dsl_prop_get_all_impl(objset_t *mos, uint64_t propobj,
 853     const char *setpoint, dsl_prop_getflags_t flags, nvlist_t *nv)
 854 {
 855         zap_cursor_t zc;
 856         zap_attribute_t za;
 857         int err = 0;
 858 
 859         for (zap_cursor_init(&zc, mos, propobj);
 860             (err = zap_cursor_retrieve(&zc, &za)) == 0;
 861             zap_cursor_advance(&zc)) {
 862                 nvlist_t *propval;
 863                 zfs_prop_t prop;
 864                 char buf[ZAP_MAXNAMELEN];
 865                 char *valstr;
 866                 const char *suffix;
 867                 const char *propname;
 868                 const char *source;
 869 
 870                 suffix = strchr(za.za_name, '$');
 871 
 872                 if (suffix == NULL) {
 873                         /*
 874                          * Skip local properties if we only want received
 875                          * properties.
 876                          */
 877                         if (flags & DSL_PROP_GET_RECEIVED)
 878                                 continue;
 879 
 880                         propname = za.za_name;
 881                         source = setpoint;
 882                 } else if (strcmp(suffix, ZPROP_INHERIT_SUFFIX) == 0) {
 883                         /* Skip explicitly inherited entries. */
 884                         continue;
 885                 } else if (strcmp(suffix, ZPROP_RECVD_SUFFIX) == 0) {
 886                         if (flags & DSL_PROP_GET_LOCAL)
 887                                 continue;
 888 
 889                         (void) strncpy(buf, za.za_name, (suffix - za.za_name));
 890                         buf[suffix - za.za_name] = '\0';
 891                         propname = buf;
 892 
 893                         if (!(flags & DSL_PROP_GET_RECEIVED)) {
 894                                 /* Skip if locally overridden. */
 895                                 err = zap_contains(mos, propobj, propname);
 896                                 if (err == 0)
 897                                         continue;
 898                                 if (err != ENOENT)
 899                                         break;
 900 
 901                                 /* Skip if explicitly inherited. */
 902                                 valstr = kmem_asprintf("%s%s", propname,
 903                                     ZPROP_INHERIT_SUFFIX);
 904                                 err = zap_contains(mos, propobj, valstr);
 905                                 strfree(valstr);
 906                                 if (err == 0)
 907                                         continue;
 908                                 if (err != ENOENT)
 909                                         break;
 910                         }
 911 
 912                         source = ((flags & DSL_PROP_GET_INHERITING) ?
 913                             setpoint : ZPROP_SOURCE_VAL_RECVD);
 914                 } else {
 915                         /*
 916                          * For backward compatibility, skip suffixes we don't
 917                          * recognize.
 918                          */
 919                         continue;
 920                 }
 921 
 922                 prop = zfs_name_to_prop(propname);
 923 
 924                 /* Skip non-inheritable properties. */
 925                 if ((flags & DSL_PROP_GET_INHERITING) && prop != ZPROP_INVAL &&
 926                     !zfs_prop_inheritable(prop))
 927                         continue;
 928 
 929                 /* Skip properties not valid for this type. */
 930                 if ((flags & DSL_PROP_GET_SNAPSHOT) && prop != ZPROP_INVAL &&
 931                     !zfs_prop_valid_for_type(prop, ZFS_TYPE_SNAPSHOT))
 932                         continue;
 933 
 934                 /* Skip properties already defined. */
 935                 if (nvlist_exists(nv, propname))
 936                         continue;
 937 
 938                 VERIFY(nvlist_alloc(&propval, NV_UNIQUE_NAME, KM_SLEEP) == 0);
 939                 if (za.za_integer_length == 1) {
 940                         /*
 941                          * String property
 942                          */
 943                         char *tmp = kmem_alloc(za.za_num_integers,
 944                             KM_SLEEP);
 945                         err = zap_lookup(mos, propobj,
 946                             za.za_name, 1, za.za_num_integers, tmp);
 947                         if (err != 0) {
 948                                 kmem_free(tmp, za.za_num_integers);
 949                                 break;
 950                         }
 951                         VERIFY(nvlist_add_string(propval, ZPROP_VALUE,
 952                             tmp) == 0);
 953                         kmem_free(tmp, za.za_num_integers);
 954                 } else {
 955                         /*
 956                          * Integer property
 957                          */
 958                         ASSERT(za.za_integer_length == 8);
 959                         (void) nvlist_add_uint64(propval, ZPROP_VALUE,
 960                             za.za_first_integer);
 961                 }
 962 
 963                 VERIFY(nvlist_add_string(propval, ZPROP_SOURCE, source) == 0);
 964                 VERIFY(nvlist_add_nvlist(nv, propname, propval) == 0);
 965                 nvlist_free(propval);
 966         }
 967         zap_cursor_fini(&zc);
 968         if (err == ENOENT)
 969                 err = 0;
 970         return (err);
 971 }
 972 
 973 /*
 974  * Iterate over all properties for this dataset and return them in an nvlist.
 975  */
 976 static int
 977 dsl_prop_get_all_ds(dsl_dataset_t *ds, nvlist_t **nvp,
 978     dsl_prop_getflags_t flags)
 979 {
 980         dsl_dir_t *dd = ds->ds_dir;
 981         dsl_pool_t *dp = dd->dd_pool;
 982         objset_t *mos = dp->dp_meta_objset;
 983         int err = 0;
 984         char setpoint[MAXNAMELEN];
 985 
 986         VERIFY(nvlist_alloc(nvp, NV_UNIQUE_NAME, KM_SLEEP) == 0);
 987 
 988         if (dsl_dataset_is_snapshot(ds))
 989                 flags |= DSL_PROP_GET_SNAPSHOT;
 990 
 991         ASSERT(dsl_pool_config_held(dp));
 992 
 993         if (ds->ds_phys->ds_props_obj != 0) {
 994                 ASSERT(flags & DSL_PROP_GET_SNAPSHOT);
 995                 dsl_dataset_name(ds, setpoint);
 996                 err = dsl_prop_get_all_impl(mos, ds->ds_phys->ds_props_obj,
 997                     setpoint, flags, *nvp);
 998                 if (err)
 999                         goto out;
1000         }
1001 
1002         for (; dd != NULL; dd = dd->dd_parent) {
1003                 if (dd != ds->ds_dir || (flags & DSL_PROP_GET_SNAPSHOT)) {
1004                         if (flags & (DSL_PROP_GET_LOCAL |
1005                             DSL_PROP_GET_RECEIVED))
1006                                 break;
1007                         flags |= DSL_PROP_GET_INHERITING;
1008                 }
1009                 dsl_dir_name(dd, setpoint);
1010                 err = dsl_prop_get_all_impl(mos, dd->dd_phys->dd_props_zapobj,
1011                     setpoint, flags, *nvp);
1012                 if (err)
1013                         break;
1014         }
1015 out:
1016         return (err);
1017 }
1018 
1019 boolean_t
1020 dsl_prop_get_hasrecvd(const char *dsname)
1021 {
1022         uint64_t dummy;
1023 
1024         return (0 ==
1025             dsl_prop_get_integer(dsname, ZPROP_HAS_RECVD, &dummy, NULL));
1026 }
1027 
1028 static int
1029 dsl_prop_set_hasrecvd_impl(const char *dsname, zprop_source_t source)
1030 {
1031         uint64_t version;
1032         spa_t *spa;
1033         int error = 0;
1034 
1035         VERIFY0(spa_open(dsname, &spa, FTAG));
1036         version = spa_version(spa);
1037         spa_close(spa, FTAG);
1038 
1039         if (version >= SPA_VERSION_RECVD_PROPS)
1040                 error = dsl_prop_set_int(dsname, ZPROP_HAS_RECVD, source, 0);
1041         return (error);
1042 }
1043 
1044 /*
1045  * Call after successfully receiving properties to ensure that only the first
1046  * receive on or after SPA_VERSION_RECVD_PROPS blows away local properties.
1047  */
1048 int
1049 dsl_prop_set_hasrecvd(const char *dsname)
1050 {
1051         int error = 0;
1052         if (!dsl_prop_get_hasrecvd(dsname))
1053                 error = dsl_prop_set_hasrecvd_impl(dsname, ZPROP_SRC_LOCAL);
1054         return (error);
1055 }
1056 
1057 void
1058 dsl_prop_unset_hasrecvd(const char *dsname)
1059 {
1060         VERIFY0(dsl_prop_set_hasrecvd_impl(dsname, ZPROP_SRC_NONE));
1061 }
1062 
1063 int
1064 dsl_prop_get_all(objset_t *os, nvlist_t **nvp)
1065 {
1066         return (dsl_prop_get_all_ds(os->os_dsl_dataset, nvp, 0));
1067 }
1068 
1069 int
1070 dsl_prop_get_received(const char *dsname, nvlist_t **nvp)
1071 {
1072         objset_t *os;
1073         int error;
1074 
1075         /*
1076          * Received properties are not distinguishable from local properties
1077          * until the dataset has received properties on or after
1078          * SPA_VERSION_RECVD_PROPS.
1079          */
1080         dsl_prop_getflags_t flags = (dsl_prop_get_hasrecvd(dsname) ?
1081             DSL_PROP_GET_RECEIVED : DSL_PROP_GET_LOCAL);
1082 
1083         error = dmu_objset_hold(dsname, FTAG, &os);
1084         if (error != 0)
1085                 return (error);
1086         error = dsl_prop_get_all_ds(os->os_dsl_dataset, nvp, flags);
1087         dmu_objset_rele(os, FTAG);
1088         return (error);
1089 }
1090 
1091 void
1092 dsl_prop_nvlist_add_uint64(nvlist_t *nv, zfs_prop_t prop, uint64_t value)
1093 {
1094         nvlist_t *propval;
1095         const char *propname = zfs_prop_to_name(prop);
1096         uint64_t default_value;
1097 
1098         if (nvlist_lookup_nvlist(nv, propname, &propval) == 0) {
1099                 VERIFY(nvlist_add_uint64(propval, ZPROP_VALUE, value) == 0);
1100                 return;
1101         }
1102 
1103         VERIFY(nvlist_alloc(&propval, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1104         VERIFY(nvlist_add_uint64(propval, ZPROP_VALUE, value) == 0);
1105         /* Indicate the default source if we can. */
1106         if (dodefault(propname, 8, 1, &default_value) == 0 &&
1107             value == default_value) {
1108                 VERIFY(nvlist_add_string(propval, ZPROP_SOURCE, "") == 0);
1109         }
1110         VERIFY(nvlist_add_nvlist(nv, propname, propval) == 0);
1111         nvlist_free(propval);
1112 }
1113 
1114 void
1115 dsl_prop_nvlist_add_string(nvlist_t *nv, zfs_prop_t prop, const char *value)
1116 {
1117         nvlist_t *propval;
1118         const char *propname = zfs_prop_to_name(prop);
1119 
1120         if (nvlist_lookup_nvlist(nv, propname, &propval) == 0) {
1121                 VERIFY(nvlist_add_string(propval, ZPROP_VALUE, value) == 0);
1122                 return;
1123         }
1124 
1125         VERIFY(nvlist_alloc(&propval, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1126         VERIFY(nvlist_add_string(propval, ZPROP_VALUE, value) == 0);
1127         VERIFY(nvlist_add_nvlist(nv, propname, propval) == 0);
1128         nvlist_free(propval);
1129 }