module/zfs/dsl_dir.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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  23  */
  24
  25 #include <sys/dmu.h>
  26 #include <sys/dmu_objset.h>
  27 #include <sys/dmu_tx.h>
  28 #include <sys/dsl_dataset.h>
  29 #include <sys/dsl_dir.h>
  30 #include <sys/dsl_prop.h>
  31 #include <sys/dsl_synctask.h>
  32 #include <sys/dsl_deleg.h>
  33 #include <sys/spa.h>
  34 #include <sys/metaslab.h>
  35 #include <sys/zap.h>
  36 #include <sys/zio.h>
  37 #include <sys/arc.h>
  38 #include <sys/sunddi.h>
  39 #include "zfs_namecheck.h"
  40
  41 static uint64_t dsl_dir_space_towrite(dsl_dir_t *dd);
  42 static void dsl_dir_set_reservation_sync(void *arg1, void *arg2, dmu_tx_t *tx);
  43
  44
  45 /* ARGSUSED */
  46 static void
  47 dsl_dir_evict(dmu_buf_t *db, void *arg)
  48 {
  49         dsl_dir_t *dd = arg;
  50         dsl_pool_t *dp = dd->dd_pool;
  51         int t;
  52
  53         for (t = 0; t < TXG_SIZE; t++) {
  54                 ASSERT(!txg_list_member(&dp->dp_dirty_dirs, dd, t));
  55                 ASSERT(dd->dd_tempreserved[t] == 0);
  56                 ASSERT(dd->dd_space_towrite[t] == 0);
  57         }
  58
  59         if (dd->dd_parent)
  60                 dsl_dir_close(dd->dd_parent, dd);
  61
  62         spa_close(dd->dd_pool->dp_spa, dd);
  63
  64         /*
  65          * The props callback list should have been cleaned up by
  66          * objset_evict().
  67          */
  68         list_destroy(&dd->dd_prop_cbs);
  69         mutex_destroy(&dd->dd_lock);
  70         kmem_free(dd, sizeof (dsl_dir_t));
  71 }
  72
  73 int
  74 dsl_dir_open_obj(dsl_pool_t *dp, uint64_t ddobj,
  75     const char *tail, void *tag, dsl_dir_t **ddp)
  76 {
  77         dmu_buf_t *dbuf;
  78         dsl_dir_t *dd;
  79         int err;
  80
  81         ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock) ||
  82             dsl_pool_sync_context(dp));
  83
  84         err = dmu_bonus_hold(dp->dp_meta_objset, ddobj, tag, &dbuf);
  85         if (err)
  86                 return (err);
  87         dd = dmu_buf_get_user(dbuf);
  88 #ifdef ZFS_DEBUG
  89         {
  90                 dmu_object_info_t doi;
  91                 dmu_object_info_from_db(dbuf, &doi);
  92                 ASSERT3U(doi.doi_type, ==, DMU_OT_DSL_DIR);
  93                 ASSERT3U(doi.doi_bonus_size, >=, sizeof (dsl_dir_phys_t));
  94         }
  95 #endif
  96         if (dd == NULL) {
  97                 dsl_dir_t *winner;
  98
  99                 dd = kmem_zalloc(sizeof (dsl_dir_t), KM_SLEEP);
 100                 dd->dd_object = ddobj;
 101                 dd->dd_dbuf = dbuf;
 102                 dd->dd_pool = dp;
 103                 dd->dd_phys = dbuf->db_data;
 104                 mutex_init(&dd->dd_lock, NULL, MUTEX_DEFAULT, NULL);
 105
 106                 list_create(&dd->dd_prop_cbs, sizeof (dsl_prop_cb_record_t),
 107                     offsetof(dsl_prop_cb_record_t, cbr_node));
 108
 109                 dsl_dir_snap_cmtime_update(dd);
 110
 111                 if (dd->dd_phys->dd_parent_obj) {
 112                         err = dsl_dir_open_obj(dp, dd->dd_phys->dd_parent_obj,
 113                             NULL, dd, &dd->dd_parent);
 114                         if (err)
 115                                 goto errout;
 116                         if (tail) {
 117 #ifdef ZFS_DEBUG
 118                                 uint64_t foundobj;
 119
 120                                 err = zap_lookup(dp->dp_meta_objset,
 121                                     dd->dd_parent->dd_phys->dd_child_dir_zapobj,
 122                                     tail, sizeof (foundobj), 1, &foundobj);
 123                                 ASSERT(err || foundobj == ddobj);
 124 #endif
 125                                 (void) strcpy(dd->dd_myname, tail);
 126                         } else {
 127                                 err = zap_value_search(dp->dp_meta_objset,
 128                                     dd->dd_parent->dd_phys->dd_child_dir_zapobj,
 129                                     ddobj, 0, dd->dd_myname);
 130                         }
 131                         if (err)
 132                                 goto errout;
 133                 } else {
 134                         (void) strcpy(dd->dd_myname, spa_name(dp->dp_spa));
 135                 }
 136
 137                 if (dsl_dir_is_clone(dd)) {
 138                         dmu_buf_t *origin_bonus;
 139                         dsl_dataset_phys_t *origin_phys;
 140
 141                         /*
 142                          * We can't open the origin dataset, because
 143                          * that would require opening this dsl_dir.
 144                          * Just look at its phys directly instead.
 145                          */
 146                         err = dmu_bonus_hold(dp->dp_meta_objset,
 147                             dd->dd_phys->dd_origin_obj, FTAG, &origin_bonus);
 148                         if (err)
 149                                 goto errout;
 150                         origin_phys = origin_bonus->db_data;
 151                         dd->dd_origin_txg =
 152                             origin_phys->ds_creation_txg;
 153                         dmu_buf_rele(origin_bonus, FTAG);
 154                 }
 155
 156                 winner = dmu_buf_set_user_ie(dbuf, dd, &dd->dd_phys,
 157                     dsl_dir_evict);
 158                 if (winner) {
 159                         if (dd->dd_parent)
 160                                 dsl_dir_close(dd->dd_parent, dd);
 161                         mutex_destroy(&dd->dd_lock);
 162                         kmem_free(dd, sizeof (dsl_dir_t));
 163                         dd = winner;
 164                 } else {
 165                         spa_open_ref(dp->dp_spa, dd);
 166                 }
 167         }
 168
 169         /*
 170          * The dsl_dir_t has both open-to-close and instantiate-to-evict
 171          * holds on the spa.  We need the open-to-close holds because
 172          * otherwise the spa_refcnt wouldn't change when we open a
 173          * dir which the spa also has open, so we could incorrectly
 174          * think it was OK to unload/export/destroy the pool.  We need
 175          * the instantiate-to-evict hold because the dsl_dir_t has a
 176          * pointer to the dd_pool, which has a pointer to the spa_t.
 177          */
 178         spa_open_ref(dp->dp_spa, tag);
 179         ASSERT3P(dd->dd_pool, ==, dp);
 180         ASSERT3U(dd->dd_object, ==, ddobj);
 181         ASSERT3P(dd->dd_dbuf, ==, dbuf);
 182         *ddp = dd;
 183         return (0);
 184
 185 errout:
 186         if (dd->dd_parent)
 187                 dsl_dir_close(dd->dd_parent, dd);
 188         mutex_destroy(&dd->dd_lock);
 189         kmem_free(dd, sizeof (dsl_dir_t));
 190         dmu_buf_rele(dbuf, tag);
 191         return (err);
 192
 193 }
 194
 195 void
 196 dsl_dir_close(dsl_dir_t *dd, void *tag)
 197 {
 198         dprintf_dd(dd, "%s\n", "");
 199         spa_close(dd->dd_pool->dp_spa, tag);
 200         dmu_buf_rele(dd->dd_dbuf, tag);
 201 }
 202
 203 /* buf must be long enough (MAXNAMELEN + strlen(MOS_DIR_NAME) + 1 should do) */
 204 void
 205 dsl_dir_name(dsl_dir_t *dd, char *buf)
 206 {
 207         if (dd->dd_parent) {
 208                 dsl_dir_name(dd->dd_parent, buf);
 209                 (void) strcat(buf, "/");
 210         } else {
 211                 buf[0] = '\0';
 212         }
 213         if (!MUTEX_HELD(&dd->dd_lock)) {
 214                 /*
 215                  * recursive mutex so that we can use
 216                  * dprintf_dd() with dd_lock held
 217                  */
 218                 mutex_enter(&dd->dd_lock);
 219                 (void) strcat(buf, dd->dd_myname);
 220                 mutex_exit(&dd->dd_lock);
 221         } else {
 222                 (void) strcat(buf, dd->dd_myname);
 223         }
 224 }
 225
 226 /* Calculate name legnth, avoiding all the strcat calls of dsl_dir_name */
 227 int
 228 dsl_dir_namelen(dsl_dir_t *dd)
 229 {
 230         int result = 0;
 231
 232         if (dd->dd_parent) {
 233                 /* parent's name + 1 for the "/" */
 234                 result = dsl_dir_namelen(dd->dd_parent) + 1;
 235         }
 236
 237         if (!MUTEX_HELD(&dd->dd_lock)) {
 238                 /* see dsl_dir_name */
 239                 mutex_enter(&dd->dd_lock);
 240                 result += strlen(dd->dd_myname);
 241                 mutex_exit(&dd->dd_lock);
 242         } else {
 243                 result += strlen(dd->dd_myname);
 244         }
 245
 246         return (result);
 247 }
 248
 249 static int
 250 getcomponent(const char *path, char *component, const char **nextp)
 251 {
 252         char *p;
 253         if ((path == NULL) || (path[0] == '\0'))
 254                 return (ENOENT);
 255         /* This would be a good place to reserve some namespace... */
 256         p = strpbrk(path, "/@");
 257         if (p && (p[1] == '/' || p[1] == '@')) {
 258                 /* two separators in a row */
 259                 return (EINVAL);
 260         }
 261         if (p == NULL || p == path) {
 262                 /*
 263                  * if the first thing is an @ or /, it had better be an
 264                  * @ and it had better not have any more ats or slashes,
 265                  * and it had better have something after the @.
 266                  */
 267                 if (p != NULL &&
 268                     (p[0] != '@' || strpbrk(path+1, "/@") || p[1] == '\0'))
 269                         return (EINVAL);
 270                 if (strlen(path) >= MAXNAMELEN)
 271                         return (ENAMETOOLONG);
 272                 (void) strcpy(component, path);
 273                 p = NULL;
 274         } else if (p[0] == '/') {
 275                 if (p-path >= MAXNAMELEN)
 276                         return (ENAMETOOLONG);
 277                 (void) strncpy(component, path, p - path);
 278                 component[p-path] = '\0';
 279                 p++;
 280         } else if (p[0] == '@') {
 281                 /*
 282                  * if the next separator is an @, there better not be
 283                  * any more slashes.
 284                  */
 285                 if (strchr(path, '/'))
 286                         return (EINVAL);
 287                 if (p-path >= MAXNAMELEN)
 288                         return (ENAMETOOLONG);
 289                 (void) strncpy(component, path, p - path);
 290                 component[p-path] = '\0';
 291         } else {
 292                 ASSERT(!"invalid p");
 293         }
 294         *nextp = p;
 295         return (0);
 296 }
 297
 298 /*
 299  * same as dsl_open_dir, ignore the first component of name and use the
 300  * spa instead
 301  */
 302 int
 303 dsl_dir_open_spa(spa_t *spa, const char *name, void *tag,
 304     dsl_dir_t **ddp, const char **tailp)
 305 {
 306         char buf[MAXNAMELEN];
 307         const char *next, *nextnext = NULL;
 308         int err;
 309         dsl_dir_t *dd;
 310         dsl_pool_t *dp;
 311         uint64_t ddobj;
 312         int openedspa = FALSE;
 313
 314         dprintf("%s\n", name);
 315
 316         err = getcomponent(name, buf, &next);
 317         if (err)
 318                 return (err);
 319         if (spa == NULL) {
 320                 err = spa_open(buf, &spa, FTAG);
 321                 if (err) {
 322                         dprintf("spa_open(%s) failed\n", buf);
 323                         return (err);
 324                 }
 325                 openedspa = TRUE;
 326
 327                 /* XXX this assertion belongs in spa_open */
 328                 ASSERT(!dsl_pool_sync_context(spa_get_dsl(spa)));
 329         }
 330
 331         dp = spa_get_dsl(spa);
 332
 333         rw_enter(&dp->dp_config_rwlock, RW_READER);
 334         err = dsl_dir_open_obj(dp, dp->dp_root_dir_obj, NULL, tag, &dd);
 335         if (err) {
 336                 rw_exit(&dp->dp_config_rwlock);
 337                 if (openedspa)
 338                         spa_close(spa, FTAG);
 339                 return (err);
 340         }
 341
 342         while (next != NULL) {
 343                 dsl_dir_t *child_ds;
 344                 err = getcomponent(next, buf, &nextnext);
 345                 if (err)
 346                         break;
 347                 ASSERT(next[0] != '\0');
 348                 if (next[0] == '@')
 349                         break;
 350                 dprintf("looking up %s in obj%lld\n",
 351                     buf, dd->dd_phys->dd_child_dir_zapobj);
 352
 353                 err = zap_lookup(dp->dp_meta_objset,
 354                     dd->dd_phys->dd_child_dir_zapobj,
 355                     buf, sizeof (ddobj), 1, &ddobj);
 356                 if (err) {
 357                         if (err == ENOENT)
 358                                 err = 0;
 359                         break;
 360                 }
 361
 362                 err = dsl_dir_open_obj(dp, ddobj, buf, tag, &child_ds);
 363                 if (err)
 364                         break;
 365                 dsl_dir_close(dd, tag);
 366                 dd = child_ds;
 367                 next = nextnext;
 368         }
 369         rw_exit(&dp->dp_config_rwlock);
 370
 371         if (err) {
 372                 dsl_dir_close(dd, tag);
 373                 if (openedspa)
 374                         spa_close(spa, FTAG);
 375                 return (err);
 376         }
 377
 378         /*
 379          * It's an error if there's more than one component left, or
 380          * tailp==NULL and there's any component left.
 381          */
 382         if (next != NULL &&
 383             (tailp == NULL || (nextnext && nextnext[0] != '\0'))) {
 384                 /* bad path name */
 385                 dsl_dir_close(dd, tag);
 386                 dprintf("next=%p (%s) tail=%p\n", next, next?next:"", tailp);
 387                 err = ENOENT;
 388         }
 389         if (tailp)
 390                 *tailp = next;
 391         if (openedspa)
 392                 spa_close(spa, FTAG);
 393         *ddp = dd;
 394         return (err);
 395 }
 396
 397 /*
 398  * Return the dsl_dir_t, and possibly the last component which couldn't
 399  * be found in *tail.  Return NULL if the path is bogus, or if
 400  * tail==NULL and we couldn't parse the whole name.  (*tail)[0] == '@'
 401  * means that the last component is a snapshot.
 402  */
 403 int
 404 dsl_dir_open(const char *name, void *tag, dsl_dir_t **ddp, const char **tailp)
 405 {
 406         return (dsl_dir_open_spa(NULL, name, tag, ddp, tailp));
 407 }
 408
 409 uint64_t
 410 dsl_dir_create_sync(dsl_pool_t *dp, dsl_dir_t *pds, const char *name,
 411     dmu_tx_t *tx)
 412 {
 413         objset_t *mos = dp->dp_meta_objset;
 414         uint64_t ddobj;
 415         dsl_dir_phys_t *ddphys;
 416         dmu_buf_t *dbuf;
 417
 418         ddobj = dmu_object_alloc(mos, DMU_OT_DSL_DIR, 0,
 419             DMU_OT_DSL_DIR, sizeof (dsl_dir_phys_t), tx);
 420         if (pds) {
 421                 VERIFY(0 == zap_add(mos, pds->dd_phys->dd_child_dir_zapobj,
 422                     name, sizeof (uint64_t), 1, &ddobj, tx));
 423         } else {
 424                 /* it's the root dir */
 425                 VERIFY(0 == zap_add(mos, DMU_POOL_DIRECTORY_OBJECT,
 426                     DMU_POOL_ROOT_DATASET, sizeof (uint64_t), 1, &ddobj, tx));
 427         }
 428         VERIFY(0 == dmu_bonus_hold(mos, ddobj, FTAG, &dbuf));
 429         dmu_buf_will_dirty(dbuf, tx);
 430         ddphys = dbuf->db_data;
 431
 432         ddphys->dd_creation_time = gethrestime_sec();
 433         if (pds)
 434                 ddphys->dd_parent_obj = pds->dd_object;
 435         ddphys->dd_props_zapobj = zap_create(mos,
 436             DMU_OT_DSL_PROPS, DMU_OT_NONE, 0, tx);
 437         ddphys->dd_child_dir_zapobj = zap_create(mos,
 438             DMU_OT_DSL_DIR_CHILD_MAP, DMU_OT_NONE, 0, tx);
 439         if (spa_version(dp->dp_spa) >= SPA_VERSION_USED_BREAKDOWN)
 440                 ddphys->dd_flags |= DD_FLAG_USED_BREAKDOWN;
 441         dmu_buf_rele(dbuf, FTAG);
 442
 443         return (ddobj);
 444 }
 445
 446 /* ARGSUSED */
 447 int
 448 dsl_dir_destroy_check(void *arg1, void *arg2, dmu_tx_t *tx)
 449 {
 450         dsl_dataset_t *ds = arg1;
 451         dsl_dir_t *dd = ds->ds_dir;
 452         dsl_pool_t *dp = dd->dd_pool;
 453         objset_t *mos = dp->dp_meta_objset;
 454         int err;
 455         uint64_t count;
 456
 457         /*
 458          * There should be exactly two holds, both from
 459          * dsl_dataset_destroy: one on the dd directory, and one on its
 460          * head ds.  Otherwise, someone is trying to lookup something
 461          * inside this dir while we want to destroy it.  The
 462          * config_rwlock ensures that nobody else opens it after we
 463          * check.
 464          */
 465         if (dmu_buf_refcount(dd->dd_dbuf) > 2)
 466                 return (EBUSY);
 467
 468         err = zap_count(mos, dd->dd_phys->dd_child_dir_zapobj, &count);
 469         if (err)
 470                 return (err);
 471         if (count != 0)
 472                 return (EEXIST);
 473
 474         return (0);
 475 }
 476
 477 void
 478 dsl_dir_destroy_sync(void *arg1, void *tag, dmu_tx_t *tx)
 479 {
 480         dsl_dataset_t *ds = arg1;
 481         dsl_dir_t *dd = ds->ds_dir;
 482         objset_t *mos = dd->dd_pool->dp_meta_objset;
 483         dsl_prop_setarg_t psa;
 484         uint64_t value = 0;
 485         uint64_t obj;
 486         dd_used_t t;
 487
 488         ASSERT(RW_WRITE_HELD(&dd->dd_pool->dp_config_rwlock));
 489         ASSERT(dd->dd_phys->dd_head_dataset_obj == 0);
 490
 491         /* Remove our reservation. */
 492         dsl_prop_setarg_init_uint64(&psa, "reservation",
 493             (ZPROP_SRC_NONE | ZPROP_SRC_LOCAL | ZPROP_SRC_RECEIVED),
 494             &value);
 495         psa.psa_effective_value = 0;    /* predict default value */
 496
 497         dsl_dir_set_reservation_sync(ds, &psa, tx);
 498
 499         ASSERT3U(dd->dd_phys->dd_used_bytes, ==, 0);
 500         ASSERT3U(dd->dd_phys->dd_reserved, ==, 0);
 501         for (t = 0; t < DD_USED_NUM; t++)
 502                 ASSERT3U(dd->dd_phys->dd_used_breakdown[t], ==, 0);
 503
 504         VERIFY(0 == zap_destroy(mos, dd->dd_phys->dd_child_dir_zapobj, tx));
 505         VERIFY(0 == zap_destroy(mos, dd->dd_phys->dd_props_zapobj, tx));
 506         VERIFY(0 == dsl_deleg_destroy(mos, dd->dd_phys->dd_deleg_zapobj, tx));
 507         VERIFY(0 == zap_remove(mos,
 508             dd->dd_parent->dd_phys->dd_child_dir_zapobj, dd->dd_myname, tx));
 509
 510         obj = dd->dd_object;
 511         dsl_dir_close(dd, tag);
 512         VERIFY(0 == dmu_object_free(mos, obj, tx));
 513 }
 514
 515 boolean_t
 516 dsl_dir_is_clone(dsl_dir_t *dd)
 517 {
 518         return (dd->dd_phys->dd_origin_obj &&
 519             (dd->dd_pool->dp_origin_snap == NULL ||
 520             dd->dd_phys->dd_origin_obj !=
 521             dd->dd_pool->dp_origin_snap->ds_object));
 522 }
 523
 524 void
 525 dsl_dir_stats(dsl_dir_t *dd, nvlist_t *nv)
 526 {
 527         mutex_enter(&dd->dd_lock);
 528         dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED,
 529             dd->dd_phys->dd_used_bytes);
 530         dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_QUOTA, dd->dd_phys->dd_quota);
 531         dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_RESERVATION,
 532             dd->dd_phys->dd_reserved);
 533         dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO,
 534             dd->dd_phys->dd_compressed_bytes == 0 ? 100 :
 535             (dd->dd_phys->dd_uncompressed_bytes * 100 /
 536             dd->dd_phys->dd_compressed_bytes));
 537         if (dd->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) {
 538                 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USEDSNAP,
 539                     dd->dd_phys->dd_used_breakdown[DD_USED_SNAP]);
 540                 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USEDDS,
 541                     dd->dd_phys->dd_used_breakdown[DD_USED_HEAD]);
 542                 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USEDREFRESERV,
 543                     dd->dd_phys->dd_used_breakdown[DD_USED_REFRSRV]);
 544                 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USEDCHILD,
 545                     dd->dd_phys->dd_used_breakdown[DD_USED_CHILD] +
 546                     dd->dd_phys->dd_used_breakdown[DD_USED_CHILD_RSRV]);
 547         }
 548         mutex_exit(&dd->dd_lock);
 549
 550         rw_enter(&dd->dd_pool->dp_config_rwlock, RW_READER);
 551         if (dsl_dir_is_clone(dd)) {
 552                 dsl_dataset_t *ds;
 553                 char buf[MAXNAMELEN];
 554
 555                 VERIFY(0 == dsl_dataset_hold_obj(dd->dd_pool,
 556                     dd->dd_phys->dd_origin_obj, FTAG, &ds));
 557                 dsl_dataset_name(ds, buf);
 558                 dsl_dataset_rele(ds, FTAG);
 559                 dsl_prop_nvlist_add_string(nv, ZFS_PROP_ORIGIN, buf);
 560         }
 561         rw_exit(&dd->dd_pool->dp_config_rwlock);
 562 }
 563
 564 void
 565 dsl_dir_dirty(dsl_dir_t *dd, dmu_tx_t *tx)
 566 {
 567         dsl_pool_t *dp = dd->dd_pool;
 568
 569         ASSERT(dd->dd_phys);
 570
 571         if (txg_list_add(&dp->dp_dirty_dirs, dd, tx->tx_txg) == 0) {
 572                 /* up the hold count until we can be written out */
 573                 dmu_buf_add_ref(dd->dd_dbuf, dd);
 574         }
 575 }
 576
 577 static int64_t
 578 parent_delta(dsl_dir_t *dd, uint64_t used, int64_t delta)
 579 {
 580         uint64_t old_accounted = MAX(used, dd->dd_phys->dd_reserved);
 581         uint64_t new_accounted = MAX(used + delta, dd->dd_phys->dd_reserved);
 582         return (new_accounted - old_accounted);
 583 }
 584
 585 void
 586 dsl_dir_sync(dsl_dir_t *dd, dmu_tx_t *tx)
 587 {
 588         ASSERT(dmu_tx_is_syncing(tx));
 589
 590         dmu_buf_will_dirty(dd->dd_dbuf, tx);
 591
 592         mutex_enter(&dd->dd_lock);
 593         ASSERT3U(dd->dd_tempreserved[tx->tx_txg&TXG_MASK], ==, 0);
 594         dprintf_dd(dd, "txg=%llu towrite=%lluK\n", tx->tx_txg,
 595             dd->dd_space_towrite[tx->tx_txg&TXG_MASK] / 1024);
 596         dd->dd_space_towrite[tx->tx_txg&TXG_MASK] = 0;
 597         mutex_exit(&dd->dd_lock);
 598
 599         /* release the hold from dsl_dir_dirty */
 600         dmu_buf_rele(dd->dd_dbuf, dd);
 601 }
 602
 603 static uint64_t
 604 dsl_dir_space_towrite(dsl_dir_t *dd)
 605 {
 606         uint64_t space = 0;
 607         int i;
 608
 609         ASSERT(MUTEX_HELD(&dd->dd_lock));
 610
 611         for (i = 0; i < TXG_SIZE; i++) {
 612                 space += dd->dd_space_towrite[i&TXG_MASK];
 613                 ASSERT3U(dd->dd_space_towrite[i&TXG_MASK], >=, 0);
 614         }
 615         return (space);
 616 }
 617
 618 /*
 619  * How much space would dd have available if ancestor had delta applied
 620  * to it?  If ondiskonly is set, we're only interested in what's
 621  * on-disk, not estimated pending changes.
 622  */
 623 uint64_t
 624 dsl_dir_space_available(dsl_dir_t *dd,
 625     dsl_dir_t *ancestor, int64_t delta, int ondiskonly)
 626 {
 627         uint64_t parentspace, myspace, quota, used;
 628
 629         /*
 630          * If there are no restrictions otherwise, assume we have
 631          * unlimited space available.
 632          */
 633         quota = UINT64_MAX;
 634         parentspace = UINT64_MAX;
 635
 636         if (dd->dd_parent != NULL) {
 637                 parentspace = dsl_dir_space_available(dd->dd_parent,
 638                     ancestor, delta, ondiskonly);
 639         }
 640
 641         mutex_enter(&dd->dd_lock);
 642         if (dd->dd_phys->dd_quota != 0)
 643                 quota = dd->dd_phys->dd_quota;
 644         used = dd->dd_phys->dd_used_bytes;
 645         if (!ondiskonly)
 646                 used += dsl_dir_space_towrite(dd);
 647
 648         if (dd->dd_parent == NULL) {
 649                 uint64_t poolsize = dsl_pool_adjustedsize(dd->dd_pool, FALSE);
 650                 quota = MIN(quota, poolsize);
 651         }
 652
 653         if (dd->dd_phys->dd_reserved > used && parentspace != UINT64_MAX) {
 654                 /*
 655                  * We have some space reserved, in addition to what our
 656                  * parent gave us.
 657                  */
 658                 parentspace += dd->dd_phys->dd_reserved - used;
 659         }
 660
 661         if (dd == ancestor) {
 662                 ASSERT(delta <= 0);
 663                 ASSERT(used >= -delta);
 664                 used += delta;
 665                 if (parentspace != UINT64_MAX)
 666                         parentspace -= delta;
 667         }
 668
 669         if (used > quota) {
 670                 /* over quota */
 671                 myspace = 0;
 672         } else {
 673                 /*
 674                  * the lesser of the space provided by our parent and
 675                  * the space left in our quota
 676                  */
 677                 myspace = MIN(parentspace, quota - used);
 678         }
 679
 680         mutex_exit(&dd->dd_lock);
 681
 682         return (myspace);
 683 }
 684
 685 struct tempreserve {
 686         list_node_t tr_node;
 687         dsl_pool_t *tr_dp;
 688         dsl_dir_t *tr_ds;
 689         uint64_t tr_size;
 690 };
 691
 692 static int
 693 dsl_dir_tempreserve_impl(dsl_dir_t *dd, uint64_t asize, boolean_t netfree,
 694     boolean_t ignorequota, boolean_t checkrefquota, list_t *tr_list,
 695     dmu_tx_t *tx, boolean_t first)
 696 {
 697         uint64_t txg = tx->tx_txg;
 698         uint64_t est_inflight, used_on_disk, quota, parent_rsrv;
 699         uint64_t deferred = 0;
 700         struct tempreserve *tr;
 701         int retval = EDQUOT;
 702         int txgidx = txg & TXG_MASK;
 703         int i;
 704         uint64_t ref_rsrv = 0;
 705
 706         ASSERT3U(txg, !=, 0);
 707         ASSERT3S(asize, >, 0);
 708
 709         mutex_enter(&dd->dd_lock);
 710
 711         /*
 712          * Check against the dsl_dir's quota.  We don't add in the delta
 713          * when checking for over-quota because they get one free hit.
 714          */
 715         est_inflight = dsl_dir_space_towrite(dd);
 716         for (i = 0; i < TXG_SIZE; i++)
 717                 est_inflight += dd->dd_tempreserved[i];
 718         used_on_disk = dd->dd_phys->dd_used_bytes;
 719
 720         /*
 721          * On the first iteration, fetch the dataset's used-on-disk and
 722          * refreservation values. Also, if checkrefquota is set, test if
 723          * allocating this space would exceed the dataset's refquota.
 724          */
 725         if (first && tx->tx_objset) {
 726                 int error;
 727                 dsl_dataset_t *ds = tx->tx_objset->os_dsl_dataset;
 728
 729                 error = dsl_dataset_check_quota(ds, checkrefquota,
 730                     asize, est_inflight, &used_on_disk, &ref_rsrv);
 731                 if (error) {
 732                         mutex_exit(&dd->dd_lock);
 733                         return (error);
 734                 }
 735         }
 736
 737         /*
 738          * If this transaction will result in a net free of space,
 739          * we want to let it through.
 740          */
 741         if (ignorequota || netfree || dd->dd_phys->dd_quota == 0)
 742                 quota = UINT64_MAX;
 743         else
 744                 quota = dd->dd_phys->dd_quota;
 745
 746         /*
 747          * Adjust the quota against the actual pool size at the root
 748          * minus any outstanding deferred frees.
 749          * To ensure that it's possible to remove files from a full
 750          * pool without inducing transient overcommits, we throttle
 751          * netfree transactions against a quota that is slightly larger,
 752          * but still within the pool's allocation slop.  In cases where
 753          * we're very close to full, this will allow a steady trickle of
 754          * removes to get through.
 755          */
 756         if (dd->dd_parent == NULL) {
 757                 spa_t *spa = dd->dd_pool->dp_spa;
 758                 uint64_t poolsize = dsl_pool_adjustedsize(dd->dd_pool, netfree);
 759                 deferred = metaslab_class_get_deferred(spa_normal_class(spa));
 760                 if (poolsize - deferred < quota) {
 761                         quota = poolsize - deferred;
 762                         retval = ENOSPC;
 763                 }
 764         }
 765
 766         /*
 767          * If they are requesting more space, and our current estimate
 768          * is over quota, they get to try again unless the actual
 769          * on-disk is over quota and there are no pending changes (which
 770          * may free up space for us).
 771          */
 772         if (used_on_disk + est_inflight >= quota) {
 773                 if (est_inflight > 0 || used_on_disk < quota ||
 774                     (retval == ENOSPC && used_on_disk < quota + deferred))
 775                         retval = ERESTART;
 776                 dprintf_dd(dd, "failing: used=%lluK inflight = %lluK "
 777                     "quota=%lluK tr=%lluK err=%d\n",
 778                     used_on_disk>>10, est_inflight>>10,
 779                     quota>>10, asize>>10, retval);
 780                 mutex_exit(&dd->dd_lock);
 781                 return (retval);
 782         }
 783
 784         /* We need to up our estimated delta before dropping dd_lock */
 785         dd->dd_tempreserved[txgidx] += asize;
 786
 787         parent_rsrv = parent_delta(dd, used_on_disk + est_inflight,
 788             asize - ref_rsrv);
 789         mutex_exit(&dd->dd_lock);
 790
 791         tr = kmem_zalloc(sizeof (struct tempreserve), KM_SLEEP);
 792         tr->tr_ds = dd;
 793         tr->tr_size = asize;
 794         list_insert_tail(tr_list, tr);
 795
 796         /* see if it's OK with our parent */
 797         if (dd->dd_parent && parent_rsrv) {
 798                 boolean_t ismos = (dd->dd_phys->dd_head_dataset_obj == 0);
 799
 800                 return (dsl_dir_tempreserve_impl(dd->dd_parent,
 801                     parent_rsrv, netfree, ismos, TRUE, tr_list, tx, FALSE));
 802         } else {
 803                 return (0);
 804         }
 805 }
 806
 807 /*
 808  * Reserve space in this dsl_dir, to be used in this tx's txg.
 809  * After the space has been dirtied (and dsl_dir_willuse_space()
 810  * has been called), the reservation should be canceled, using
 811  * dsl_dir_tempreserve_clear().
 812  */
 813 int
 814 dsl_dir_tempreserve_space(dsl_dir_t *dd, uint64_t lsize, uint64_t asize,
 815     uint64_t fsize, uint64_t usize, void **tr_cookiep, dmu_tx_t *tx)
 816 {
 817         int err;
 818         list_t *tr_list;
 819
 820         if (asize == 0) {
 821                 *tr_cookiep = NULL;
 822                 return (0);
 823         }
 824
 825         tr_list = kmem_alloc(sizeof (list_t), KM_SLEEP);
 826         list_create(tr_list, sizeof (struct tempreserve),
 827             offsetof(struct tempreserve, tr_node));
 828         ASSERT3S(asize, >, 0);
 829         ASSERT3S(fsize, >=, 0);
 830
 831         err = arc_tempreserve_space(lsize, tx->tx_txg);
 832         if (err == 0) {
 833                 struct tempreserve *tr;
 834
 835                 tr = kmem_zalloc(sizeof (struct tempreserve), KM_SLEEP);
 836                 tr->tr_size = lsize;
 837                 list_insert_tail(tr_list, tr);
 838
 839                 err = dsl_pool_tempreserve_space(dd->dd_pool, asize, tx);
 840         } else {
 841                 if (err == EAGAIN) {
 842                         txg_delay(dd->dd_pool, tx->tx_txg, 1);
 843                         err = ERESTART;
 844                 }
 845                 dsl_pool_memory_pressure(dd->dd_pool);
 846         }
 847
 848         if (err == 0) {
 849                 struct tempreserve *tr;
 850
 851                 tr = kmem_zalloc(sizeof (struct tempreserve), KM_SLEEP);
 852                 tr->tr_dp = dd->dd_pool;
 853                 tr->tr_size = asize;
 854                 list_insert_tail(tr_list, tr);
 855
 856                 err = dsl_dir_tempreserve_impl(dd, asize, fsize >= asize,
 857                     FALSE, asize > usize, tr_list, tx, TRUE);
 858         }
 859
 860         if (err)
 861                 dsl_dir_tempreserve_clear(tr_list, tx);
 862         else
 863                 *tr_cookiep = tr_list;
 864
 865         return (err);
 866 }
 867
 868 /*
 869  * Clear a temporary reservation that we previously made with
 870  * dsl_dir_tempreserve_space().
 871  */
 872 void
 873 dsl_dir_tempreserve_clear(void *tr_cookie, dmu_tx_t *tx)
 874 {
 875         int txgidx = tx->tx_txg & TXG_MASK;
 876         list_t *tr_list = tr_cookie;
 877         struct tempreserve *tr;
 878
 879         ASSERT3U(tx->tx_txg, !=, 0);
 880
 881         if (tr_cookie == NULL)
 882                 return;
 883
 884         while ((tr = list_head(tr_list))) {
 885                 if (tr->tr_dp) {
 886                         dsl_pool_tempreserve_clear(tr->tr_dp, tr->tr_size, tx);
 887                 } else if (tr->tr_ds) {
 888                         mutex_enter(&tr->tr_ds->dd_lock);
 889                         ASSERT3U(tr->tr_ds->dd_tempreserved[txgidx], >=,
 890                             tr->tr_size);
 891                         tr->tr_ds->dd_tempreserved[txgidx] -= tr->tr_size;
 892                         mutex_exit(&tr->tr_ds->dd_lock);
 893                 } else {
 894                         arc_tempreserve_clear(tr->tr_size);
 895                 }
 896                 list_remove(tr_list, tr);
 897                 kmem_free(tr, sizeof (struct tempreserve));
 898         }
 899
 900         kmem_free(tr_list, sizeof (list_t));
 901 }
 902
 903 static void
 904 dsl_dir_willuse_space_impl(dsl_dir_t *dd, int64_t space, dmu_tx_t *tx)
 905 {
 906         int64_t parent_space;
 907         uint64_t est_used;
 908
 909         mutex_enter(&dd->dd_lock);
 910         if (space > 0)
 911                 dd->dd_space_towrite[tx->tx_txg & TXG_MASK] += space;
 912
 913         est_used = dsl_dir_space_towrite(dd) + dd->dd_phys->dd_used_bytes;
 914         parent_space = parent_delta(dd, est_used, space);
 915         mutex_exit(&dd->dd_lock);
 916
 917         /* Make sure that we clean up dd_space_to* */
 918         dsl_dir_dirty(dd, tx);
 919
 920         /* XXX this is potentially expensive and unnecessary... */
 921         if (parent_space && dd->dd_parent)
 922                 dsl_dir_willuse_space_impl(dd->dd_parent, parent_space, tx);
 923 }
 924
 925 /*
 926  * Call in open context when we think we're going to write/free space,
 927  * eg. when dirtying data.  Be conservative (ie. OK to write less than
 928  * this or free more than this, but don't write more or free less).
 929  */
 930 void
 931 dsl_dir_willuse_space(dsl_dir_t *dd, int64_t space, dmu_tx_t *tx)
 932 {
 933         dsl_pool_willuse_space(dd->dd_pool, space, tx);
 934         dsl_dir_willuse_space_impl(dd, space, tx);
 935 }
 936
 937 /* call from syncing context when we actually write/free space for this dd */
 938 void
 939 dsl_dir_diduse_space(dsl_dir_t *dd, dd_used_t type,
 940     int64_t used, int64_t compressed, int64_t uncompressed, dmu_tx_t *tx)
 941 {
 942         int64_t accounted_delta;
 943         boolean_t needlock = !MUTEX_HELD(&dd->dd_lock);
 944
 945         ASSERT(dmu_tx_is_syncing(tx));
 946         ASSERT(type < DD_USED_NUM);
 947
 948         dsl_dir_dirty(dd, tx);
 949
 950         if (needlock)
 951                 mutex_enter(&dd->dd_lock);
 952         accounted_delta = parent_delta(dd, dd->dd_phys->dd_used_bytes, used);
 953         ASSERT(used >= 0 || dd->dd_phys->dd_used_bytes >= -used);
 954         ASSERT(compressed >= 0 ||
 955             dd->dd_phys->dd_compressed_bytes >= -compressed);
 956         ASSERT(uncompressed >= 0 ||
 957             dd->dd_phys->dd_uncompressed_bytes >= -uncompressed);
 958         dd->dd_phys->dd_used_bytes += used;
 959         dd->dd_phys->dd_uncompressed_bytes += uncompressed;
 960         dd->dd_phys->dd_compressed_bytes += compressed;
 961
 962         if (dd->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) {
 963                 ASSERT(used > 0 ||
 964                     dd->dd_phys->dd_used_breakdown[type] >= -used);
 965                 dd->dd_phys->dd_used_breakdown[type] += used;
 966 #ifdef DEBUG
 967                 {
 968                         dd_used_t t;
 969                         uint64_t u = 0;
 970                         for (t = 0; t < DD_USED_NUM; t++)
 971                                 u += dd->dd_phys->dd_used_breakdown[t];
 972                         ASSERT3U(u, ==, dd->dd_phys->dd_used_bytes);
 973                 }
 974 #endif
 975         }
 976         if (needlock)
 977                 mutex_exit(&dd->dd_lock);
 978
 979         if (dd->dd_parent != NULL) {
 980                 dsl_dir_diduse_space(dd->dd_parent, DD_USED_CHILD,
 981                     accounted_delta, compressed, uncompressed, tx);
 982                 dsl_dir_transfer_space(dd->dd_parent,
 983                     used - accounted_delta,
 984                     DD_USED_CHILD_RSRV, DD_USED_CHILD, tx);
 985         }
 986 }
 987
 988 void
 989 dsl_dir_transfer_space(dsl_dir_t *dd, int64_t delta,
 990     dd_used_t oldtype, dd_used_t newtype, dmu_tx_t *tx)
 991 {
 992         boolean_t needlock = !MUTEX_HELD(&dd->dd_lock);
 993
 994         ASSERT(dmu_tx_is_syncing(tx));
 995         ASSERT(oldtype < DD_USED_NUM);
 996         ASSERT(newtype < DD_USED_NUM);
 997
 998         if (delta == 0 || !(dd->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN))
 999                 return;
1000
1001         dsl_dir_dirty(dd, tx);
1002         if (needlock)
1003                 mutex_enter(&dd->dd_lock);
1004         ASSERT(delta > 0 ?
1005             dd->dd_phys->dd_used_breakdown[oldtype] >= delta :
1006             dd->dd_phys->dd_used_breakdown[newtype] >= -delta);
1007         ASSERT(dd->dd_phys->dd_used_bytes >= ABS(delta));
1008         dd->dd_phys->dd_used_breakdown[oldtype] -= delta;
1009         dd->dd_phys->dd_used_breakdown[newtype] += delta;
1010         if (needlock)
1011                 mutex_exit(&dd->dd_lock);
1012 }
1013
1014 static int
1015 dsl_dir_set_quota_check(void *arg1, void *arg2, dmu_tx_t *tx)
1016 {
1017         dsl_dataset_t *ds = arg1;
1018         dsl_dir_t *dd = ds->ds_dir;
1019         dsl_prop_setarg_t *psa = arg2;
1020         int err;
1021         uint64_t towrite;
1022
1023         if ((err = dsl_prop_predict_sync(ds->ds_dir, psa)) != 0)
1024                 return (err);
1025
1026         if (psa->psa_effective_value == 0)
1027                 return (0);
1028
1029         mutex_enter(&dd->dd_lock);
1030         /*
1031          * If we are doing the preliminary check in open context, and
1032          * there are pending changes, then don't fail it, since the
1033          * pending changes could under-estimate the amount of space to be
1034          * freed up.
1035          */
1036         towrite = dsl_dir_space_towrite(dd);
1037         if ((dmu_tx_is_syncing(tx) || towrite == 0) &&
1038             (psa->psa_effective_value < dd->dd_phys->dd_reserved ||
1039             psa->psa_effective_value < dd->dd_phys->dd_used_bytes + towrite)) {
1040                 err = ENOSPC;
1041         }
1042         mutex_exit(&dd->dd_lock);
1043         return (err);
1044 }
1045
1046 extern dsl_syncfunc_t dsl_prop_set_sync;
1047
1048 static void
1049 dsl_dir_set_quota_sync(void *arg1, void *arg2, dmu_tx_t *tx)
1050 {
1051         dsl_dataset_t *ds = arg1;
1052         dsl_dir_t *dd = ds->ds_dir;
1053         dsl_prop_setarg_t *psa = arg2;
1054         uint64_t effective_value = psa->psa_effective_value;
1055
1056         dsl_prop_set_sync(ds, psa, tx);
1057         DSL_PROP_CHECK_PREDICTION(dd, psa);
1058
1059         dmu_buf_will_dirty(dd->dd_dbuf, tx);
1060
1061         mutex_enter(&dd->dd_lock);
1062         dd->dd_phys->dd_quota = effective_value;
1063         mutex_exit(&dd->dd_lock);
1064
1065         spa_history_log_internal(LOG_DS_QUOTA, dd->dd_pool->dp_spa,
1066             tx, "%lld dataset = %llu ",
1067             (longlong_t)effective_value, dd->dd_phys->dd_head_dataset_obj);
1068 }
1069
1070 int
1071 dsl_dir_set_quota(const char *ddname, zprop_source_t source, uint64_t quota)
1072 {
1073         dsl_dir_t *dd;
1074         dsl_dataset_t *ds;
1075         dsl_prop_setarg_t psa;
1076         int err;
1077
1078         dsl_prop_setarg_init_uint64(&psa, "quota", source, &quota);
1079
1080         err = dsl_dataset_hold(ddname, FTAG, &ds);
1081         if (err)
1082                 return (err);
1083
1084         err = dsl_dir_open(ddname, FTAG, &dd, NULL);
1085         if (err) {
1086                 dsl_dataset_rele(ds, FTAG);
1087                 return (err);
1088         }
1089
1090         ASSERT(ds->ds_dir == dd);
1091
1092         /*
1093          * If someone removes a file, then tries to set the quota, we want to
1094          * make sure the file freeing takes effect.
1095          */
1096         txg_wait_open(dd->dd_pool, 0);
1097
1098         err = dsl_sync_task_do(dd->dd_pool, dsl_dir_set_quota_check,
1099             dsl_dir_set_quota_sync, ds, &psa, 0);
1100
1101         dsl_dir_close(dd, FTAG);
1102         dsl_dataset_rele(ds, FTAG);
1103         return (err);
1104 }
1105
1106 int
1107 dsl_dir_set_reservation_check(void *arg1, void *arg2, dmu_tx_t *tx)
1108 {
1109         dsl_dataset_t *ds = arg1;
1110         dsl_dir_t *dd = ds->ds_dir;
1111         dsl_prop_setarg_t *psa = arg2;
1112         uint64_t effective_value;
1113         uint64_t used, avail;
1114         int err;
1115
1116         if ((err = dsl_prop_predict_sync(ds->ds_dir, psa)) != 0)
1117                 return (err);
1118
1119         effective_value = psa->psa_effective_value;
1120
1121         /*
1122          * If we are doing the preliminary check in open context, the
1123          * space estimates may be inaccurate.
1124          */
1125         if (!dmu_tx_is_syncing(tx))
1126                 return (0);
1127
1128         mutex_enter(&dd->dd_lock);
1129         used = dd->dd_phys->dd_used_bytes;
1130         mutex_exit(&dd->dd_lock);
1131
1132         if (dd->dd_parent) {
1133                 avail = dsl_dir_space_available(dd->dd_parent,
1134                     NULL, 0, FALSE);
1135         } else {
1136                 avail = dsl_pool_adjustedsize(dd->dd_pool, B_FALSE) - used;
1137         }
1138
1139         if (MAX(used, effective_value) > MAX(used, dd->dd_phys->dd_reserved)) {
1140                 uint64_t delta = MAX(used, effective_value) -
1141                     MAX(used, dd->dd_phys->dd_reserved);
1142
1143                 if (delta > avail)
1144                         return (ENOSPC);
1145                 if (dd->dd_phys->dd_quota > 0 &&
1146                     effective_value > dd->dd_phys->dd_quota)
1147                         return (ENOSPC);
1148         }
1149
1150         return (0);
1151 }
1152
1153 static void
1154 dsl_dir_set_reservation_sync(void *arg1, void *arg2, dmu_tx_t *tx)
1155 {
1156         dsl_dataset_t *ds = arg1;
1157         dsl_dir_t *dd = ds->ds_dir;
1158         dsl_prop_setarg_t *psa = arg2;
1159         uint64_t effective_value = psa->psa_effective_value;
1160         uint64_t used;
1161         int64_t delta;
1162
1163         dsl_prop_set_sync(ds, psa, tx);
1164         DSL_PROP_CHECK_PREDICTION(dd, psa);
1165
1166         dmu_buf_will_dirty(dd->dd_dbuf, tx);
1167
1168         mutex_enter(&dd->dd_lock);
1169         used = dd->dd_phys->dd_used_bytes;
1170         delta = MAX(used, effective_value) -
1171             MAX(used, dd->dd_phys->dd_reserved);
1172         dd->dd_phys->dd_reserved = effective_value;
1173
1174         if (dd->dd_parent != NULL) {
1175                 /* Roll up this additional usage into our ancestors */
1176                 dsl_dir_diduse_space(dd->dd_parent, DD_USED_CHILD_RSRV,
1177                     delta, 0, 0, tx);
1178         }
1179         mutex_exit(&dd->dd_lock);
1180
1181         spa_history_log_internal(LOG_DS_RESERVATION, dd->dd_pool->dp_spa,
1182             tx, "%lld dataset = %llu",
1183             (longlong_t)effective_value, dd->dd_phys->dd_head_dataset_obj);
1184 }
1185
1186 int
1187 dsl_dir_set_reservation(const char *ddname, zprop_source_t source,
1188     uint64_t reservation)
1189 {
1190         dsl_dir_t *dd;
1191         dsl_dataset_t *ds;
1192         dsl_prop_setarg_t psa;
1193         int err;
1194
1195         dsl_prop_setarg_init_uint64(&psa, "reservation", source, &reservation);
1196
1197         err = dsl_dataset_hold(ddname, FTAG, &ds);
1198         if (err)
1199                 return (err);
1200
1201         err = dsl_dir_open(ddname, FTAG, &dd, NULL);
1202         if (err) {
1203                 dsl_dataset_rele(ds, FTAG);
1204                 return (err);
1205         }
1206
1207         ASSERT(ds->ds_dir == dd);
1208
1209         err = dsl_sync_task_do(dd->dd_pool, dsl_dir_set_reservation_check,
1210             dsl_dir_set_reservation_sync, ds, &psa, 0);
1211
1212         dsl_dir_close(dd, FTAG);
1213         dsl_dataset_rele(ds, FTAG);
1214         return (err);
1215 }
1216
1217 static dsl_dir_t *
1218 closest_common_ancestor(dsl_dir_t *ds1, dsl_dir_t *ds2)
1219 {
1220         for (; ds1; ds1 = ds1->dd_parent) {
1221                 dsl_dir_t *dd;
1222                 for (dd = ds2; dd; dd = dd->dd_parent) {
1223                         if (ds1 == dd)
1224                                 return (dd);
1225                 }
1226         }
1227         return (NULL);
1228 }
1229
1230 /*
1231  * If delta is applied to dd, how much of that delta would be applied to
1232  * ancestor?  Syncing context only.
1233  */
1234 static int64_t
1235 would_change(dsl_dir_t *dd, int64_t delta, dsl_dir_t *ancestor)
1236 {
1237         if (dd == ancestor)
1238                 return (delta);
1239
1240         mutex_enter(&dd->dd_lock);
1241         delta = parent_delta(dd, dd->dd_phys->dd_used_bytes, delta);
1242         mutex_exit(&dd->dd_lock);
1243         return (would_change(dd->dd_parent, delta, ancestor));
1244 }
1245
1246 struct renamearg {
1247         dsl_dir_t *newparent;
1248         const char *mynewname;
1249 };
1250
1251 static int
1252 dsl_dir_rename_check(void *arg1, void *arg2, dmu_tx_t *tx)
1253 {
1254         dsl_dir_t *dd = arg1;
1255         struct renamearg *ra = arg2;
1256         dsl_pool_t *dp = dd->dd_pool;
1257         objset_t *mos = dp->dp_meta_objset;
1258         int err;
1259         uint64_t val;
1260
1261         /*
1262          * There should only be one reference, from dmu_objset_rename().
1263          * Fleeting holds are also possible (eg, from "zfs list" getting
1264          * stats), but any that are present in open context will likely
1265          * be gone by syncing context, so only fail from syncing
1266          * context.
1267          */
1268         if (dmu_tx_is_syncing(tx) && dmu_buf_refcount(dd->dd_dbuf) > 1)
1269                 return (EBUSY);
1270
1271         /* check for existing name */
1272         err = zap_lookup(mos, ra->newparent->dd_phys->dd_child_dir_zapobj,
1273             ra->mynewname, 8, 1, &val);
1274         if (err == 0)
1275                 return (EEXIST);
1276         if (err != ENOENT)
1277                 return (err);
1278
1279         if (ra->newparent != dd->dd_parent) {
1280                 /* is there enough space? */
1281                 uint64_t myspace =
1282                     MAX(dd->dd_phys->dd_used_bytes, dd->dd_phys->dd_reserved);
1283
1284                 /* no rename into our descendant */
1285                 if (closest_common_ancestor(dd, ra->newparent) == dd)
1286                         return (EINVAL);
1287
1288                 if ((err = dsl_dir_transfer_possible(dd->dd_parent,
1289                     ra->newparent, myspace)))
1290                         return (err);
1291         }
1292
1293         return (0);
1294 }
1295
1296 static void
1297 dsl_dir_rename_sync(void *arg1, void *arg2, dmu_tx_t *tx)
1298 {
1299         dsl_dir_t *dd = arg1;
1300         struct renamearg *ra = arg2;
1301         dsl_pool_t *dp = dd->dd_pool;
1302         objset_t *mos = dp->dp_meta_objset;
1303         int err;
1304
1305         ASSERT(dmu_buf_refcount(dd->dd_dbuf) <= 2);
1306
1307         if (ra->newparent != dd->dd_parent) {
1308                 dsl_dir_diduse_space(dd->dd_parent, DD_USED_CHILD,
1309                     -dd->dd_phys->dd_used_bytes,
1310                     -dd->dd_phys->dd_compressed_bytes,
1311                     -dd->dd_phys->dd_uncompressed_bytes, tx);
1312                 dsl_dir_diduse_space(ra->newparent, DD_USED_CHILD,
1313                     dd->dd_phys->dd_used_bytes,
1314                     dd->dd_phys->dd_compressed_bytes,
1315                     dd->dd_phys->dd_uncompressed_bytes, tx);
1316
1317                 if (dd->dd_phys->dd_reserved > dd->dd_phys->dd_used_bytes) {
1318                         uint64_t unused_rsrv = dd->dd_phys->dd_reserved -
1319                             dd->dd_phys->dd_used_bytes;
1320
1321                         dsl_dir_diduse_space(dd->dd_parent, DD_USED_CHILD_RSRV,
1322                             -unused_rsrv, 0, 0, tx);
1323                         dsl_dir_diduse_space(ra->newparent, DD_USED_CHILD_RSRV,
1324                             unused_rsrv, 0, 0, tx);
1325                 }
1326         }
1327
1328         dmu_buf_will_dirty(dd->dd_dbuf, tx);
1329
1330         /* remove from old parent zapobj */
1331         err = zap_remove(mos, dd->dd_parent->dd_phys->dd_child_dir_zapobj,
1332             dd->dd_myname, tx);
1333         ASSERT3U(err, ==, 0);
1334
1335         (void) strcpy(dd->dd_myname, ra->mynewname);
1336         dsl_dir_close(dd->dd_parent, dd);
1337         dd->dd_phys->dd_parent_obj = ra->newparent->dd_object;
1338         VERIFY(0 == dsl_dir_open_obj(dd->dd_pool,
1339             ra->newparent->dd_object, NULL, dd, &dd->dd_parent));
1340
1341         /* add to new parent zapobj */
1342         err = zap_add(mos, ra->newparent->dd_phys->dd_child_dir_zapobj,
1343             dd->dd_myname, 8, 1, &dd->dd_object, tx);
1344         ASSERT3U(err, ==, 0);
1345
1346         spa_history_log_internal(LOG_DS_RENAME, dd->dd_pool->dp_spa,
1347             tx, "dataset = %llu", dd->dd_phys->dd_head_dataset_obj);
1348 }
1349
1350 int
1351 dsl_dir_rename(dsl_dir_t *dd, const char *newname)
1352 {
1353         struct renamearg ra;
1354         int err;
1355
1356         /* new parent should exist */
1357         err = dsl_dir_open(newname, FTAG, &ra.newparent, &ra.mynewname);
1358         if (err)
1359                 return (err);
1360
1361         /* can't rename to different pool */
1362         if (dd->dd_pool != ra.newparent->dd_pool) {
1363                 err = ENXIO;
1364                 goto out;
1365         }
1366
1367         /* new name should not already exist */
1368         if (ra.mynewname == NULL) {
1369                 err = EEXIST;
1370                 goto out;
1371         }
1372
1373         err = dsl_sync_task_do(dd->dd_pool,
1374             dsl_dir_rename_check, dsl_dir_rename_sync, dd, &ra, 3);
1375
1376 out:
1377         dsl_dir_close(ra.newparent, FTAG);
1378         return (err);
1379 }
1380
1381 int
1382 dsl_dir_transfer_possible(dsl_dir_t *sdd, dsl_dir_t *tdd, uint64_t space)
1383 {
1384         dsl_dir_t *ancestor;
1385         int64_t adelta;
1386         uint64_t avail;
1387
1388         ancestor = closest_common_ancestor(sdd, tdd);
1389         adelta = would_change(sdd, -space, ancestor);
1390         avail = dsl_dir_space_available(tdd, ancestor, adelta, FALSE);
1391         if (avail < space)
1392                 return (ENOSPC);
1393
1394         return (0);
1395 }
1396
1397 timestruc_t
1398 dsl_dir_snap_cmtime(dsl_dir_t *dd)
1399 {
1400         timestruc_t t;
1401
1402         mutex_enter(&dd->dd_lock);
1403         t = dd->dd_snap_cmtime;
1404         mutex_exit(&dd->dd_lock);
1405
1406         return (t);
1407 }
1408
1409 void
1410 dsl_dir_snap_cmtime_update(dsl_dir_t *dd)
1411 {
1412         timestruc_t t;
1413
1414         gethrestime(&t);
1415         mutex_enter(&dd->dd_lock);
1416         dd->dd_snap_cmtime = t;
1417         mutex_exit(&dd->dd_lock);
1418 }