external/cddl/osnet/dist/uts/common/fs/zfs/dsl_prop.c

   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 2008 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 #pragma ident   "%Z%%M% %I%     %E% SMI"
  27
  28 #include <sys/dmu.h>
  29 #include <sys/dmu_objset.h>
  30 #include <sys/dmu_tx.h>
  31 #include <sys/dsl_dataset.h>
  32 #include <sys/dsl_dir.h>
  33 #include <sys/dsl_prop.h>
  34 #include <sys/dsl_synctask.h>
  35 #include <sys/spa.h>
  36 #include <sys/zio_checksum.h> /* for the default checksum value */
  37 #include <sys/zap.h>
  38 #include <sys/fs/zfs.h>
  39
  40 #include "zfs_prop.h"
  41
  42 static int
  43 dodefault(const char *propname, int intsz, int numint, void *buf)
  44 {
  45         zfs_prop_t prop;
  46
  47         /*
  48          * The setonce properties are read-only, BUT they still
  49          * have a default value that can be used as the initial
  50          * value.
  51          */
  52         if ((prop = zfs_name_to_prop(propname)) == ZPROP_INVAL ||
  53             (zfs_prop_readonly(prop) && !zfs_prop_setonce(prop)))
  54                 return (ENOENT);
  55
  56         if (zfs_prop_get_type(prop) == PROP_TYPE_STRING) {
  57                 if (intsz != 1)
  58                         return (EOVERFLOW);
  59                 (void) strncpy(buf, zfs_prop_default_string(prop),
  60                     numint);
  61         } else {
  62                 if (intsz != 8 || numint < 1)
  63                         return (EOVERFLOW);
  64
  65                 *(uint64_t *)buf = zfs_prop_default_numeric(prop);
  66         }
  67
  68         return (0);
  69 }
  70
  71 int
  72 dsl_prop_get_dd(dsl_dir_t *dd, const char *propname,
  73     int intsz, int numint, void *buf, char *setpoint)
  74 {
  75         int err = ENOENT;
  76         objset_t *mos = dd->dd_pool->dp_meta_objset;
  77         zfs_prop_t prop;
  78
  79         ASSERT(RW_LOCK_HELD(&dd->dd_pool->dp_config_rwlock));
  80
  81         if (setpoint)
  82                 setpoint[0] = '\0';
  83
  84         prop = zfs_name_to_prop(propname);
  85
  86         /*
  87          * Note: dd may be NULL, therefore we shouldn't dereference it
  88          * ouside this loop.
  89          */
  90         for (; dd != NULL; dd = dd->dd_parent) {
  91                 ASSERT(RW_LOCK_HELD(&dd->dd_pool->dp_config_rwlock));
  92                 err = zap_lookup(mos, dd->dd_phys->dd_props_zapobj,
  93                     propname, intsz, numint, buf);
  94                 if (err != ENOENT) {
  95                         if (setpoint)
  96                                 dsl_dir_name(dd, setpoint);
  97                         break;
  98                 }
  99
 100                 /*
 101                  * Break out of this loop for non-inheritable properties.
 102                  */
 103                 if (prop != ZPROP_INVAL && !zfs_prop_inheritable(prop))
 104                         break;
 105         }
 106         if (err == ENOENT)
 107                 err = dodefault(propname, intsz, numint, buf);
 108
 109         return (err);
 110 }
 111
 112 int
 113 dsl_prop_get_ds(dsl_dataset_t *ds, const char *propname,
 114     int intsz, int numint, void *buf, char *setpoint)
 115 {
 116         ASSERT(RW_LOCK_HELD(&ds->ds_dir->dd_pool->dp_config_rwlock));
 117
 118         if (ds->ds_phys->ds_props_obj) {
 119                 int err = zap_lookup(ds->ds_dir->dd_pool->dp_meta_objset,
 120                     ds->ds_phys->ds_props_obj, propname, intsz, numint, buf);
 121                 if (err != ENOENT) {
 122                         if (setpoint)
 123                                 dsl_dataset_name(ds, setpoint);
 124                         return (err);
 125                 }
 126         }
 127
 128         return (dsl_prop_get_dd(ds->ds_dir, propname,
 129             intsz, numint, buf, setpoint));
 130 }
 131
 132 /*
 133  * Register interest in the named property.  We'll call the callback
 134  * once to notify it of the current property value, and again each time
 135  * the property changes, until this callback is unregistered.
 136  *
 137  * Return 0 on success, errno if the prop is not an integer value.
 138  */
 139 int
 140 dsl_prop_register(dsl_dataset_t *ds, const char *propname,
 141     dsl_prop_changed_cb_t *callback, void *cbarg)
 142 {
 143         dsl_dir_t *dd = ds->ds_dir;
 144         dsl_pool_t *dp = dd->dd_pool;
 145         uint64_t value;
 146         dsl_prop_cb_record_t *cbr;
 147         int err;
 148         int need_rwlock;
 149
 150         need_rwlock = !RW_WRITE_HELD(&dp->dp_config_rwlock);
 151         if (need_rwlock)
 152                 rw_enter(&dp->dp_config_rwlock, RW_READER);
 153
 154         err = dsl_prop_get_ds(ds, propname, 8, 1, &value, NULL);
 155         if (err != 0) {
 156                 if (need_rwlock)
 157                         rw_exit(&dp->dp_config_rwlock);
 158                 return (err);
 159         }
 160
 161         cbr = kmem_alloc(sizeof (dsl_prop_cb_record_t), KM_SLEEP);
 162         cbr->cbr_ds = ds;
 163         cbr->cbr_propname = kmem_alloc(strlen(propname)+1, KM_SLEEP);
 164         (void) strcpy((char *)cbr->cbr_propname, propname);
 165         cbr->cbr_func = callback;
 166         cbr->cbr_arg = cbarg;
 167         mutex_enter(&dd->dd_lock);
 168         list_insert_head(&dd->dd_prop_cbs, cbr);
 169         mutex_exit(&dd->dd_lock);
 170
 171         cbr->cbr_func(cbr->cbr_arg, value);
 172
 173         VERIFY(0 == dsl_dir_open_obj(dp, dd->dd_object,
 174             NULL, cbr, &dd));
 175         if (need_rwlock)
 176                 rw_exit(&dp->dp_config_rwlock);
 177         /* Leave dir open until this callback is unregistered */
 178         return (0);
 179 }
 180
 181 int
 182 dsl_prop_get(const char *dsname, const char *propname,
 183     int intsz, int numints, void *buf, char *setpoint)
 184 {
 185         dsl_dataset_t *ds;
 186         int err;
 187
 188         err = dsl_dataset_hold(dsname, FTAG, &ds);
 189         if (err)
 190                 return (err);
 191
 192         rw_enter(&ds->ds_dir->dd_pool->dp_config_rwlock, RW_READER);
 193         err = dsl_prop_get_ds(ds, propname, intsz, numints, buf, setpoint);
 194         rw_exit(&ds->ds_dir->dd_pool->dp_config_rwlock);
 195
 196         dsl_dataset_rele(ds, FTAG);
 197         return (err);
 198 }
 199
 200 /*
 201  * Get the current property value.  It may have changed by the time this
 202  * function returns, so it is NOT safe to follow up with
 203  * dsl_prop_register() and assume that the value has not changed in
 204  * between.
 205  *
 206  * Return 0 on success, ENOENT if ddname is invalid.
 207  */
 208 int
 209 dsl_prop_get_integer(const char *ddname, const char *propname,
 210     uint64_t *valuep, char *setpoint)
 211 {
 212         return (dsl_prop_get(ddname, propname, 8, 1, valuep, setpoint));
 213 }
 214
 215 /*
 216  * Unregister this callback.  Return 0 on success, ENOENT if ddname is
 217  * invalid, ENOMSG if no matching callback registered.
 218  */
 219 int
 220 dsl_prop_unregister(dsl_dataset_t *ds, const char *propname,
 221     dsl_prop_changed_cb_t *callback, void *cbarg)
 222 {
 223         dsl_dir_t *dd = ds->ds_dir;
 224         dsl_prop_cb_record_t *cbr;
 225
 226         mutex_enter(&dd->dd_lock);
 227         for (cbr = list_head(&dd->dd_prop_cbs);
 228             cbr; cbr = list_next(&dd->dd_prop_cbs, cbr)) {
 229                 if (cbr->cbr_ds == ds &&
 230                     cbr->cbr_func == callback &&
 231                     cbr->cbr_arg == cbarg &&
 232                     strcmp(cbr->cbr_propname, propname) == 0)
 233                         break;
 234         }
 235
 236         if (cbr == NULL) {
 237                 mutex_exit(&dd->dd_lock);
 238                 return (ENOMSG);
 239         }
 240
 241         list_remove(&dd->dd_prop_cbs, cbr);
 242         mutex_exit(&dd->dd_lock);
 243         kmem_free((void*)cbr->cbr_propname, strlen(cbr->cbr_propname)+1);
 244         kmem_free(cbr, sizeof (dsl_prop_cb_record_t));
 245
 246         /* Clean up from dsl_prop_register */
 247         dsl_dir_close(dd, cbr);
 248         return (0);
 249 }
 250
 251 /*
 252  * Return the number of callbacks that are registered for this dataset.
 253  */
 254 int
 255 dsl_prop_numcb(dsl_dataset_t *ds)
 256 {
 257         dsl_dir_t *dd = ds->ds_dir;
 258         dsl_prop_cb_record_t *cbr;
 259         int num = 0;
 260
 261         mutex_enter(&dd->dd_lock);
 262         for (cbr = list_head(&dd->dd_prop_cbs);
 263             cbr; cbr = list_next(&dd->dd_prop_cbs, cbr)) {
 264                 if (cbr->cbr_ds == ds)
 265                         num++;
 266         }
 267         mutex_exit(&dd->dd_lock);
 268
 269         return (num);
 270 }
 271
 272 static void
 273 dsl_prop_changed_notify(dsl_pool_t *dp, uint64_t ddobj,
 274     const char *propname, uint64_t value, int first)
 275 {
 276         dsl_dir_t *dd;
 277         dsl_prop_cb_record_t *cbr;
 278         objset_t *mos = dp->dp_meta_objset;
 279         zap_cursor_t zc;
 280         zap_attribute_t *za;
 281         int err;
 282         uint64_t dummyval;
 283
 284         ASSERT(RW_WRITE_HELD(&dp->dp_config_rwlock));
 285         err = dsl_dir_open_obj(dp, ddobj, NULL, FTAG, &dd);
 286         if (err)
 287                 return;
 288
 289         if (!first) {
 290                 /*
 291                  * If the prop is set here, then this change is not
 292                  * being inherited here or below; stop the recursion.
 293                  */
 294                 err = zap_lookup(mos, dd->dd_phys->dd_props_zapobj, propname,
 295                     8, 1, &dummyval);
 296                 if (err == 0) {
 297                         dsl_dir_close(dd, FTAG);
 298                         return;
 299                 }
 300                 ASSERT3U(err, ==, ENOENT);
 301         }
 302
 303         mutex_enter(&dd->dd_lock);
 304         for (cbr = list_head(&dd->dd_prop_cbs); cbr;
 305             cbr = list_next(&dd->dd_prop_cbs, cbr)) {
 306                 uint64_t propobj = cbr->cbr_ds->ds_phys->ds_props_obj;
 307
 308                 if (strcmp(cbr->cbr_propname, propname) != 0)
 309                         continue;
 310
 311                 /*
 312                  * If the property is set on this ds, then it is not
 313                  * inherited here; don't call the callback.
 314                  */
 315                 if (propobj && 0 == zap_lookup(mos, propobj, propname,
 316                     8, 1, &dummyval))
 317                         continue;
 318
 319                 cbr->cbr_func(cbr->cbr_arg, value);
 320         }
 321         mutex_exit(&dd->dd_lock);
 322
 323         za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
 324         for (zap_cursor_init(&zc, mos,
 325             dd->dd_phys->dd_child_dir_zapobj);
 326             zap_cursor_retrieve(&zc, za) == 0;
 327             zap_cursor_advance(&zc)) {
 328                 dsl_prop_changed_notify(dp, za->za_first_integer,
 329                     propname, value, FALSE);
 330         }
 331         kmem_free(za, sizeof (zap_attribute_t));
 332         zap_cursor_fini(&zc);
 333         dsl_dir_close(dd, FTAG);
 334 }
 335
 336 struct prop_set_arg {
 337         const char *name;
 338         int intsz;
 339         int numints;
 340         const void *buf;
 341 };
 342
 343
 344 static void
 345 dsl_prop_set_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx)
 346 {
 347         dsl_dataset_t *ds = arg1;
 348         struct prop_set_arg *psa = arg2;
 349         objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
 350         uint64_t zapobj, intval;
 351         int isint;
 352         char valbuf[32];
 353         char *valstr;
 354
 355         isint = (dodefault(psa->name, 8, 1, &intval) == 0);
 356
 357         if (dsl_dataset_is_snapshot(ds)) {
 358                 ASSERT(spa_version(ds->ds_dir->dd_pool->dp_spa) >=
 359                     SPA_VERSION_SNAP_PROPS);
 360                 if (ds->ds_phys->ds_props_obj == 0) {
 361                         dmu_buf_will_dirty(ds->ds_dbuf, tx);
 362                         ds->ds_phys->ds_props_obj =
 363                             zap_create(mos,
 364                             DMU_OT_DSL_PROPS, DMU_OT_NONE, 0, tx);
 365                 }
 366                 zapobj = ds->ds_phys->ds_props_obj;
 367         } else {
 368                 zapobj = ds->ds_dir->dd_phys->dd_props_zapobj;
 369         }
 370
 371         if (psa->numints == 0) {
 372                 int err = zap_remove(mos, zapobj, psa->name, tx);
 373                 ASSERT(err == 0 || err == ENOENT);
 374                 if (isint) {
 375                         VERIFY(0 == dsl_prop_get_ds(ds,
 376                             psa->name, 8, 1, &intval, NULL));
 377                 }
 378         } else {
 379                 VERIFY(0 == zap_update(mos, zapobj, psa->name,
 380                     psa->intsz, psa->numints, psa->buf, tx));
 381                 if (isint)
 382                         intval = *(uint64_t *)psa->buf;
 383         }
 384
 385         if (isint) {
 386                 if (dsl_dataset_is_snapshot(ds)) {
 387                         dsl_prop_cb_record_t *cbr;
 388                         /*
 389                          * It's a snapshot; nothing can inherit this
 390                          * property, so just look for callbacks on this
 391                          * ds here.
 392                          */
 393                         mutex_enter(&ds->ds_dir->dd_lock);
 394                         for (cbr = list_head(&ds->ds_dir->dd_prop_cbs); cbr;
 395                             cbr = list_next(&ds->ds_dir->dd_prop_cbs, cbr)) {
 396                                 if (cbr->cbr_ds == ds &&
 397                                     strcmp(cbr->cbr_propname, psa->name) == 0)
 398                                         cbr->cbr_func(cbr->cbr_arg, intval);
 399                         }
 400                         mutex_exit(&ds->ds_dir->dd_lock);
 401                 } else {
 402                         dsl_prop_changed_notify(ds->ds_dir->dd_pool,
 403                             ds->ds_dir->dd_object, psa->name, intval, TRUE);
 404                 }
 405         }
 406         if (isint) {
 407                 (void) snprintf(valbuf, sizeof (valbuf),
 408                     "%lld", (longlong_t)intval);
 409                 valstr = valbuf;
 410         } else {
 411                 valstr = (char *)psa->buf;
 412         }
 413         spa_history_internal_log((psa->numints == 0) ? LOG_DS_INHERIT :
 414             LOG_DS_PROPSET, ds->ds_dir->dd_pool->dp_spa, tx, cr,
 415             "%s=%s dataset = %llu", psa->name, valstr, ds->ds_object);
 416 }
 417
 418 void
 419 dsl_prop_set_uint64_sync(dsl_dir_t *dd, const char *name, uint64_t val,
 420     cred_t *cr, dmu_tx_t *tx)
 421 {
 422         objset_t *mos = dd->dd_pool->dp_meta_objset;
 423         uint64_t zapobj = dd->dd_phys->dd_props_zapobj;
 424
 425         ASSERT(dmu_tx_is_syncing(tx));
 426
 427         VERIFY(0 == zap_update(mos, zapobj, name, sizeof (val), 1, &val, tx));
 428
 429         dsl_prop_changed_notify(dd->dd_pool, dd->dd_object, name, val, TRUE);
 430
 431         spa_history_internal_log(LOG_DS_PROPSET, dd->dd_pool->dp_spa, tx, cr,
 432             "%s=%llu dataset = %llu", name, (u_longlong_t)val,
 433             dd->dd_phys->dd_head_dataset_obj);
 434 }
 435
 436 int
 437 dsl_prop_set(const char *dsname, const char *propname,
 438     int intsz, int numints, const void *buf)
 439 {
 440         dsl_dataset_t *ds;
 441         int err;
 442         struct prop_set_arg psa;
 443
 444         /*
 445          * We must do these checks before we get to the syncfunc, since
 446          * it can't fail.
 447          */
 448         if (strlen(propname) >= ZAP_MAXNAMELEN)
 449                 return (ENAMETOOLONG);
 450         if (intsz * numints >= ZAP_MAXVALUELEN)
 451                 return (E2BIG);
 452
 453         err = dsl_dataset_hold(dsname, FTAG, &ds);
 454         if (err)
 455                 return (err);
 456
 457         if (dsl_dataset_is_snapshot(ds) &&
 458             spa_version(ds->ds_dir->dd_pool->dp_spa) < SPA_VERSION_SNAP_PROPS) {
 459                 dsl_dataset_rele(ds, FTAG);
 460                 return (ENOTSUP);
 461         }
 462
 463         psa.name = propname;
 464         psa.intsz = intsz;
 465         psa.numints = numints;
 466         psa.buf = buf;
 467         err = dsl_sync_task_do(ds->ds_dir->dd_pool,
 468             NULL, dsl_prop_set_sync, ds, &psa, 2);
 469
 470         dsl_dataset_rele(ds, FTAG);
 471         return (err);
 472 }
 473
 474 /*
 475  * Iterate over all properties for this dataset and return them in an nvlist.
 476  */
 477 int
 478 dsl_prop_get_all(objset_t *os, nvlist_t **nvp, boolean_t local)
 479 {
 480         dsl_dataset_t *ds = os->os->os_dsl_dataset;
 481         dsl_dir_t *dd = ds->ds_dir;
 482         boolean_t snapshot = dsl_dataset_is_snapshot(ds);
 483         int err = 0;
 484         dsl_pool_t *dp = dd->dd_pool;
 485         objset_t *mos = dp->dp_meta_objset;
 486         uint64_t propobj = ds->ds_phys->ds_props_obj;
 487
 488         VERIFY(nvlist_alloc(nvp, NV_UNIQUE_NAME, KM_SLEEP) == 0);
 489
 490         if (local && snapshot && !propobj)
 491                 return (0);
 492
 493         rw_enter(&dp->dp_config_rwlock, RW_READER);
 494         while (dd != NULL) {
 495                 char setpoint[MAXNAMELEN];
 496                 zap_cursor_t zc;
 497                 zap_attribute_t za;
 498                 dsl_dir_t *dd_next;
 499
 500                 if (propobj) {
 501                         dsl_dataset_name(ds, setpoint);
 502                         dd_next = dd;
 503                 } else {
 504                         dsl_dir_name(dd, setpoint);
 505                         propobj = dd->dd_phys->dd_props_zapobj;
 506                         dd_next = dd->dd_parent;
 507                 }
 508
 509                 for (zap_cursor_init(&zc, mos, propobj);
 510                     (err = zap_cursor_retrieve(&zc, &za)) == 0;
 511                     zap_cursor_advance(&zc)) {
 512                         nvlist_t *propval;
 513                         zfs_prop_t prop = zfs_name_to_prop(za.za_name);
 514
 515                         /* Skip non-inheritable properties. */
 516                         if (prop != ZPROP_INVAL &&
 517                             !zfs_prop_inheritable(prop) &&
 518                             (dd != ds->ds_dir || (snapshot && dd != dd_next)))
 519                                 continue;
 520
 521                         /* Skip properties not valid for this type. */
 522                         if (snapshot && prop != ZPROP_INVAL &&
 523                             !zfs_prop_valid_for_type(prop, ZFS_TYPE_SNAPSHOT))
 524                                 continue;
 525
 526                         /* Skip properties already defined */
 527                         if (nvlist_lookup_nvlist(*nvp, za.za_name,
 528                             &propval) == 0)
 529                                 continue;
 530
 531                         VERIFY(nvlist_alloc(&propval, NV_UNIQUE_NAME,
 532                             KM_SLEEP) == 0);
 533                         if (za.za_integer_length == 1) {
 534                                 /*
 535                                  * String property
 536                                  */
 537                                 char *tmp = kmem_alloc(za.za_num_integers,
 538                                     KM_SLEEP);
 539                                 err = zap_lookup(mos, propobj,
 540                                     za.za_name, 1, za.za_num_integers, tmp);
 541                                 if (err != 0) {
 542                                         kmem_free(tmp, za.za_num_integers);
 543                                         break;
 544                                 }
 545                                 VERIFY(nvlist_add_string(propval, ZPROP_VALUE,
 546                                     tmp) == 0);
 547                                 kmem_free(tmp, za.za_num_integers);
 548                         } else {
 549                                 /*
 550                                  * Integer property
 551                                  */
 552                                 ASSERT(za.za_integer_length == 8);
 553                                 (void) nvlist_add_uint64(propval, ZPROP_VALUE,
 554                                     za.za_first_integer);
 555                         }
 556
 557                         VERIFY(nvlist_add_string(propval, ZPROP_SOURCE,
 558                             setpoint) == 0);
 559                         VERIFY(nvlist_add_nvlist(*nvp, za.za_name,
 560                             propval) == 0);
 561                         nvlist_free(propval);
 562                 }
 563                 zap_cursor_fini(&zc);
 564
 565                 if (err != ENOENT)
 566                         break;
 567                 err = 0;
 568                 /*
 569                  * If we are just after the props that have been set
 570                  * locally, then we are done after the first iteration.
 571                  */
 572                 if (local)
 573                         break;
 574                 dd = dd_next;
 575                 propobj = 0;
 576         }
 577         rw_exit(&dp->dp_config_rwlock);
 578
 579         return (err);
 580 }
 581
 582 void
 583 dsl_prop_nvlist_add_uint64(nvlist_t *nv, zfs_prop_t prop, uint64_t value)
 584 {
 585         nvlist_t *propval;
 586
 587         VERIFY(nvlist_alloc(&propval, NV_UNIQUE_NAME, KM_SLEEP) == 0);
 588         VERIFY(nvlist_add_uint64(propval, ZPROP_VALUE, value) == 0);
 589         VERIFY(nvlist_add_nvlist(nv, zfs_prop_to_name(prop), propval) == 0);
 590         nvlist_free(propval);
 591 }
 592
 593 void
 594 dsl_prop_nvlist_add_string(nvlist_t *nv, zfs_prop_t prop, const char *value)
 595 {
 596         nvlist_t *propval;
 597
 598         VERIFY(nvlist_alloc(&propval, NV_UNIQUE_NAME, KM_SLEEP) == 0);
 599         VERIFY(nvlist_add_string(propval, ZPROP_VALUE, value) == 0);
 600         VERIFY(nvlist_add_nvlist(nv, zfs_prop_to_name(prop), propval) == 0);
 601         nvlist_free(propval);
 602 }