usr/src/uts/common/fs/zfs/dsl_deadlist.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) 2010, Oracle and/or its affiliates. All rights reserved.
  23  * Copyright (c) 2012 by Delphix. All rights reserved.
  24  * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
  25  * Copyright (c) 2014 Integros [integros.com]
  26  */
  27
  28 #include <sys/dsl_dataset.h>
  29 #include <sys/dmu.h>
  30 #include <sys/refcount.h>
  31 #include <sys/zap.h>
  32 #include <sys/zfs_context.h>
  33 #include <sys/dsl_pool.h>
  34
  35 /*
  36  * Deadlist concurrency:
  37  *
  38  * Deadlists can only be modified from the syncing thread.
  39  *
  40  * Except for dsl_deadlist_insert(), it can only be modified with the
  41  * dp_config_rwlock held with RW_WRITER.
  42  *
  43  * The accessors (dsl_deadlist_space() and dsl_deadlist_space_range()) can
  44  * be called concurrently, from open context, with the dl_config_rwlock held
  45  * with RW_READER.
  46  *
  47  * Therefore, we only need to provide locking between dsl_deadlist_insert() and
  48  * the accessors, protecting:
  49  *     dl_phys->dl_used,comp,uncomp
  50  *     and protecting the dl_tree from being loaded.
  51  * The locking is provided by dl_lock.  Note that locking on the bpobj_t
  52  * provides its own locking, and dl_oldfmt is immutable.
  53  */
  54
  55 static int
  56 dsl_deadlist_compare(const void *arg1, const void *arg2)
  57 {
  58         const dsl_deadlist_entry_t *dle1 = arg1;
  59         const dsl_deadlist_entry_t *dle2 = arg2;
  60
  61         if (dle1->dle_mintxg < dle2->dle_mintxg)
  62                 return (-1);
  63         else if (dle1->dle_mintxg > dle2->dle_mintxg)
  64                 return (+1);
  65         else
  66                 return (0);
  67 }
  68
  69 static void
  70 dsl_deadlist_load_tree(dsl_deadlist_t *dl)
  71 {
  72         zap_cursor_t zc;
  73         zap_attribute_t za;
  74
  75         ASSERT(!dl->dl_oldfmt);
  76         if (dl->dl_havetree)
  77                 return;
  78
  79         avl_create(&dl->dl_tree, dsl_deadlist_compare,
  80             sizeof (dsl_deadlist_entry_t),
  81             offsetof(dsl_deadlist_entry_t, dle_node));
  82         for (zap_cursor_init(&zc, dl->dl_os, dl->dl_object);
  83             zap_cursor_retrieve(&zc, &za) == 0;
  84             zap_cursor_advance(&zc)) {
  85                 dsl_deadlist_entry_t *dle = kmem_alloc(sizeof (*dle), KM_SLEEP);
  86                 dle->dle_mintxg = strtonum(za.za_name, NULL);
  87                 VERIFY3U(0, ==, bpobj_open(&dle->dle_bpobj, dl->dl_os,
  88                     za.za_first_integer));
  89                 avl_add(&dl->dl_tree, dle);
  90         }
  91         zap_cursor_fini(&zc);
  92         dl->dl_havetree = B_TRUE;
  93 }
  94
  95 void
  96 dsl_deadlist_open(dsl_deadlist_t *dl, objset_t *os, uint64_t object)
  97 {
  98         dmu_object_info_t doi;
  99
 100         mutex_init(&dl->dl_lock, NULL, MUTEX_DEFAULT, NULL);
 101         dl->dl_os = os;
 102         dl->dl_object = object;
 103         VERIFY3U(0, ==, dmu_bonus_hold(os, object, dl, &dl->dl_dbuf));
 104         dmu_object_info_from_db(dl->dl_dbuf, &doi);
 105         if (doi.doi_type == DMU_OT_BPOBJ) {
 106                 dmu_buf_rele(dl->dl_dbuf, dl);
 107                 dl->dl_dbuf = NULL;
 108                 dl->dl_oldfmt = B_TRUE;
 109                 VERIFY3U(0, ==, bpobj_open(&dl->dl_bpobj, os, object));
 110                 return;
 111         }
 112
 113         dl->dl_oldfmt = B_FALSE;
 114         dl->dl_phys = dl->dl_dbuf->db_data;
 115         dl->dl_havetree = B_FALSE;
 116 }
 117
 118 void
 119 dsl_deadlist_close(dsl_deadlist_t *dl)
 120 {
 121         void *cookie = NULL;
 122         dsl_deadlist_entry_t *dle;
 123
 124         dl->dl_os = NULL;
 125
 126         if (dl->dl_oldfmt) {
 127                 dl->dl_oldfmt = B_FALSE;
 128                 bpobj_close(&dl->dl_bpobj);
 129                 return;
 130         }
 131
 132         if (dl->dl_havetree) {
 133                 while ((dle = avl_destroy_nodes(&dl->dl_tree, &cookie))
 134                     != NULL) {
 135                         bpobj_close(&dle->dle_bpobj);
 136                         kmem_free(dle, sizeof (*dle));
 137                 }
 138                 avl_destroy(&dl->dl_tree);
 139         }
 140         dmu_buf_rele(dl->dl_dbuf, dl);
 141         mutex_destroy(&dl->dl_lock);
 142         dl->dl_dbuf = NULL;
 143         dl->dl_phys = NULL;
 144 }
 145
 146 uint64_t
 147 dsl_deadlist_alloc(objset_t *os, dmu_tx_t *tx)
 148 {
 149         if (spa_version(dmu_objset_spa(os)) < SPA_VERSION_DEADLISTS)
 150                 return (bpobj_alloc(os, SPA_OLD_MAXBLOCKSIZE, tx));
 151         return (zap_create(os, DMU_OT_DEADLIST, DMU_OT_DEADLIST_HDR,
 152             sizeof (dsl_deadlist_phys_t), tx));
 153 }
 154
 155 void
 156 dsl_deadlist_free(objset_t *os, uint64_t dlobj, dmu_tx_t *tx)
 157 {
 158         dmu_object_info_t doi;
 159         zap_cursor_t zc;
 160         zap_attribute_t za;
 161
 162         VERIFY3U(0, ==, dmu_object_info(os, dlobj, &doi));
 163         if (doi.doi_type == DMU_OT_BPOBJ) {
 164                 bpobj_free(os, dlobj, tx);
 165                 return;
 166         }
 167
 168         for (zap_cursor_init(&zc, os, dlobj);
 169             zap_cursor_retrieve(&zc, &za) == 0;
 170             zap_cursor_advance(&zc)) {
 171                 uint64_t obj = za.za_first_integer;
 172                 if (obj == dmu_objset_pool(os)->dp_empty_bpobj)
 173                         bpobj_decr_empty(os, tx);
 174                 else
 175                         bpobj_free(os, obj, tx);
 176         }
 177         zap_cursor_fini(&zc);
 178         VERIFY3U(0, ==, dmu_object_free(os, dlobj, tx));
 179 }
 180
 181 static void
 182 dle_enqueue(dsl_deadlist_t *dl, dsl_deadlist_entry_t *dle,
 183     const blkptr_t *bp, dmu_tx_t *tx)
 184 {
 185         if (dle->dle_bpobj.bpo_object ==
 186             dmu_objset_pool(dl->dl_os)->dp_empty_bpobj) {
 187                 uint64_t obj = bpobj_alloc(dl->dl_os, SPA_OLD_MAXBLOCKSIZE, tx);
 188                 bpobj_close(&dle->dle_bpobj);
 189                 bpobj_decr_empty(dl->dl_os, tx);
 190                 VERIFY3U(0, ==, bpobj_open(&dle->dle_bpobj, dl->dl_os, obj));
 191                 VERIFY3U(0, ==, zap_update_int_key(dl->dl_os, dl->dl_object,
 192                     dle->dle_mintxg, obj, tx));
 193         }
 194         bpobj_enqueue(&dle->dle_bpobj, bp, tx);
 195 }
 196
 197 static void
 198 dle_enqueue_subobj(dsl_deadlist_t *dl, dsl_deadlist_entry_t *dle,
 199     uint64_t obj, dmu_tx_t *tx)
 200 {
 201         if (dle->dle_bpobj.bpo_object !=
 202             dmu_objset_pool(dl->dl_os)->dp_empty_bpobj) {
 203                 bpobj_enqueue_subobj(&dle->dle_bpobj, obj, tx);
 204         } else {
 205                 bpobj_close(&dle->dle_bpobj);
 206                 bpobj_decr_empty(dl->dl_os, tx);
 207                 VERIFY3U(0, ==, bpobj_open(&dle->dle_bpobj, dl->dl_os, obj));
 208                 VERIFY3U(0, ==, zap_update_int_key(dl->dl_os, dl->dl_object,
 209                     dle->dle_mintxg, obj, tx));
 210         }
 211 }
 212
 213 void
 214 dsl_deadlist_insert(dsl_deadlist_t *dl, const blkptr_t *bp, dmu_tx_t *tx)
 215 {
 216         dsl_deadlist_entry_t dle_tofind;
 217         dsl_deadlist_entry_t *dle;
 218         avl_index_t where;
 219
 220         if (dl->dl_oldfmt) {
 221                 bpobj_enqueue(&dl->dl_bpobj, bp, tx);
 222                 return;
 223         }
 224
 225         dsl_deadlist_load_tree(dl);
 226
 227         dmu_buf_will_dirty(dl->dl_dbuf, tx);
 228         mutex_enter(&dl->dl_lock);
 229         dl->dl_phys->dl_used +=
 230             bp_get_dsize_sync(dmu_objset_spa(dl->dl_os), bp);
 231         dl->dl_phys->dl_comp += BP_GET_PSIZE(bp);
 232         dl->dl_phys->dl_uncomp += BP_GET_UCSIZE(bp);
 233         mutex_exit(&dl->dl_lock);
 234
 235         dle_tofind.dle_mintxg = bp->blk_birth;
 236         dle = avl_find(&dl->dl_tree, &dle_tofind, &where);
 237         if (dle == NULL)
 238                 dle = avl_nearest(&dl->dl_tree, where, AVL_BEFORE);
 239         else
 240                 dle = AVL_PREV(&dl->dl_tree, dle);
 241         dle_enqueue(dl, dle, bp, tx);
 242 }
 243
 244 /*
 245  * Insert new key in deadlist, which must be > all current entries.
 246  * mintxg is not inclusive.
 247  */
 248 void
 249 dsl_deadlist_add_key(dsl_deadlist_t *dl, uint64_t mintxg, dmu_tx_t *tx)
 250 {
 251         uint64_t obj;
 252         dsl_deadlist_entry_t *dle;
 253
 254         if (dl->dl_oldfmt)
 255                 return;
 256
 257         dsl_deadlist_load_tree(dl);
 258
 259         dle = kmem_alloc(sizeof (*dle), KM_SLEEP);
 260         dle->dle_mintxg = mintxg;
 261         obj = bpobj_alloc_empty(dl->dl_os, SPA_OLD_MAXBLOCKSIZE, tx);
 262         VERIFY3U(0, ==, bpobj_open(&dle->dle_bpobj, dl->dl_os, obj));
 263         avl_add(&dl->dl_tree, dle);
 264
 265         VERIFY3U(0, ==, zap_add_int_key(dl->dl_os, dl->dl_object,
 266             mintxg, obj, tx));
 267 }
 268
 269 /*
 270  * Remove this key, merging its entries into the previous key.
 271  */
 272 void
 273 dsl_deadlist_remove_key(dsl_deadlist_t *dl, uint64_t mintxg, dmu_tx_t *tx)
 274 {
 275         dsl_deadlist_entry_t dle_tofind;
 276         dsl_deadlist_entry_t *dle, *dle_prev;
 277
 278         if (dl->dl_oldfmt)
 279                 return;
 280
 281         dsl_deadlist_load_tree(dl);
 282
 283         dle_tofind.dle_mintxg = mintxg;
 284         dle = avl_find(&dl->dl_tree, &dle_tofind, NULL);
 285         dle_prev = AVL_PREV(&dl->dl_tree, dle);
 286
 287         dle_enqueue_subobj(dl, dle_prev, dle->dle_bpobj.bpo_object, tx);
 288
 289         avl_remove(&dl->dl_tree, dle);
 290         bpobj_close(&dle->dle_bpobj);
 291         kmem_free(dle, sizeof (*dle));
 292
 293         VERIFY3U(0, ==, zap_remove_int(dl->dl_os, dl->dl_object, mintxg, tx));
 294 }
 295
 296 /*
 297  * Walk ds's snapshots to regenerate generate ZAP & AVL.
 298  */
 299 static void
 300 dsl_deadlist_regenerate(objset_t *os, uint64_t dlobj,
 301     uint64_t mrs_obj, dmu_tx_t *tx)
 302 {
 303         dsl_deadlist_t dl;
 304         dsl_pool_t *dp = dmu_objset_pool(os);
 305
 306         dsl_deadlist_open(&dl, os, dlobj);
 307         if (dl.dl_oldfmt) {
 308                 dsl_deadlist_close(&dl);
 309                 return;
 310         }
 311
 312         while (mrs_obj != 0) {
 313                 dsl_dataset_t *ds;
 314                 VERIFY3U(0, ==, dsl_dataset_hold_obj(dp, mrs_obj, FTAG, &ds));
 315                 dsl_deadlist_add_key(&dl,
 316                     dsl_dataset_phys(ds)->ds_prev_snap_txg, tx);
 317                 mrs_obj = dsl_dataset_phys(ds)->ds_prev_snap_obj;
 318                 dsl_dataset_rele(ds, FTAG);
 319         }
 320         dsl_deadlist_close(&dl);
 321 }
 322
 323 uint64_t
 324 dsl_deadlist_clone(dsl_deadlist_t *dl, uint64_t maxtxg,
 325     uint64_t mrs_obj, dmu_tx_t *tx)
 326 {
 327         dsl_deadlist_entry_t *dle;
 328         uint64_t newobj;
 329
 330         newobj = dsl_deadlist_alloc(dl->dl_os, tx);
 331
 332         if (dl->dl_oldfmt) {
 333                 dsl_deadlist_regenerate(dl->dl_os, newobj, mrs_obj, tx);
 334                 return (newobj);
 335         }
 336
 337         dsl_deadlist_load_tree(dl);
 338
 339         for (dle = avl_first(&dl->dl_tree); dle;
 340             dle = AVL_NEXT(&dl->dl_tree, dle)) {
 341                 uint64_t obj;
 342
 343                 if (dle->dle_mintxg >= maxtxg)
 344                         break;
 345
 346                 obj = bpobj_alloc_empty(dl->dl_os, SPA_OLD_MAXBLOCKSIZE, tx);
 347                 VERIFY3U(0, ==, zap_add_int_key(dl->dl_os, newobj,
 348                     dle->dle_mintxg, obj, tx));
 349         }
 350         return (newobj);
 351 }
 352
 353 void
 354 dsl_deadlist_space(dsl_deadlist_t *dl,
 355     uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
 356 {
 357         if (dl->dl_oldfmt) {
 358                 VERIFY3U(0, ==, bpobj_space(&dl->dl_bpobj,
 359                     usedp, compp, uncompp));
 360                 return;
 361         }
 362
 363         mutex_enter(&dl->dl_lock);
 364         *usedp = dl->dl_phys->dl_used;
 365         *compp = dl->dl_phys->dl_comp;
 366         *uncompp = dl->dl_phys->dl_uncomp;
 367         mutex_exit(&dl->dl_lock);
 368 }
 369
 370 /*
 371  * return space used in the range (mintxg, maxtxg].
 372  * Includes maxtxg, does not include mintxg.
 373  * mintxg and maxtxg must both be keys in the deadlist (unless maxtxg is
 374  * larger than any bp in the deadlist (eg. UINT64_MAX)).
 375  */
 376 void
 377 dsl_deadlist_space_range(dsl_deadlist_t *dl, uint64_t mintxg, uint64_t maxtxg,
 378     uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
 379 {
 380         dsl_deadlist_entry_t *dle;
 381         dsl_deadlist_entry_t dle_tofind;
 382         avl_index_t where;
 383
 384         if (dl->dl_oldfmt) {
 385                 VERIFY3U(0, ==, bpobj_space_range(&dl->dl_bpobj,
 386                     mintxg, maxtxg, usedp, compp, uncompp));
 387                 return;
 388         }
 389
 390         *usedp = *compp = *uncompp = 0;
 391
 392         mutex_enter(&dl->dl_lock);
 393         dsl_deadlist_load_tree(dl);
 394         dle_tofind.dle_mintxg = mintxg;
 395         dle = avl_find(&dl->dl_tree, &dle_tofind, &where);
 396         /*
 397          * If we don't find this mintxg, there shouldn't be anything
 398          * after it either.
 399          */
 400         ASSERT(dle != NULL ||
 401             avl_nearest(&dl->dl_tree, where, AVL_AFTER) == NULL);
 402
 403         for (; dle && dle->dle_mintxg < maxtxg;
 404             dle = AVL_NEXT(&dl->dl_tree, dle)) {
 405                 uint64_t used, comp, uncomp;
 406
 407                 VERIFY3U(0, ==, bpobj_space(&dle->dle_bpobj,
 408                     &used, &comp, &uncomp));
 409
 410                 *usedp += used;
 411                 *compp += comp;
 412                 *uncompp += uncomp;
 413         }
 414         mutex_exit(&dl->dl_lock);
 415 }
 416
 417 static void
 418 dsl_deadlist_insert_bpobj(dsl_deadlist_t *dl, uint64_t obj, uint64_t birth,
 419     dmu_tx_t *tx)
 420 {
 421         dsl_deadlist_entry_t dle_tofind;
 422         dsl_deadlist_entry_t *dle;
 423         avl_index_t where;
 424         uint64_t used, comp, uncomp;
 425         bpobj_t bpo;
 426
 427         VERIFY3U(0, ==, bpobj_open(&bpo, dl->dl_os, obj));
 428         VERIFY3U(0, ==, bpobj_space(&bpo, &used, &comp, &uncomp));
 429         bpobj_close(&bpo);
 430
 431         dsl_deadlist_load_tree(dl);
 432
 433         dmu_buf_will_dirty(dl->dl_dbuf, tx);
 434         mutex_enter(&dl->dl_lock);
 435         dl->dl_phys->dl_used += used;
 436         dl->dl_phys->dl_comp += comp;
 437         dl->dl_phys->dl_uncomp += uncomp;
 438         mutex_exit(&dl->dl_lock);
 439
 440         dle_tofind.dle_mintxg = birth;
 441         dle = avl_find(&dl->dl_tree, &dle_tofind, &where);
 442         if (dle == NULL)
 443                 dle = avl_nearest(&dl->dl_tree, where, AVL_BEFORE);
 444         dle_enqueue_subobj(dl, dle, obj, tx);
 445 }
 446
 447 static int
 448 dsl_deadlist_insert_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx)
 449 {
 450         dsl_deadlist_t *dl = arg;
 451         dsl_deadlist_insert(dl, bp, tx);
 452         return (0);
 453 }
 454
 455 /*
 456  * Merge the deadlist pointed to by 'obj' into dl.  obj will be left as
 457  * an empty deadlist.
 458  */
 459 void
 460 dsl_deadlist_merge(dsl_deadlist_t *dl, uint64_t obj, dmu_tx_t *tx)
 461 {
 462         zap_cursor_t zc;
 463         zap_attribute_t za;
 464         dmu_buf_t *bonus;
 465         dsl_deadlist_phys_t *dlp;
 466         dmu_object_info_t doi;
 467
 468         VERIFY3U(0, ==, dmu_object_info(dl->dl_os, obj, &doi));
 469         if (doi.doi_type == DMU_OT_BPOBJ) {
 470                 bpobj_t bpo;
 471                 VERIFY3U(0, ==, bpobj_open(&bpo, dl->dl_os, obj));
 472                 VERIFY3U(0, ==, bpobj_iterate(&bpo,
 473                     dsl_deadlist_insert_cb, dl, tx));
 474                 bpobj_close(&bpo);
 475                 return;
 476         }
 477
 478         for (zap_cursor_init(&zc, dl->dl_os, obj);
 479             zap_cursor_retrieve(&zc, &za) == 0;
 480             zap_cursor_advance(&zc)) {
 481                 uint64_t mintxg = strtonum(za.za_name, NULL);
 482                 dsl_deadlist_insert_bpobj(dl, za.za_first_integer, mintxg, tx);
 483                 VERIFY3U(0, ==, zap_remove_int(dl->dl_os, obj, mintxg, tx));
 484         }
 485         zap_cursor_fini(&zc);
 486
 487         VERIFY3U(0, ==, dmu_bonus_hold(dl->dl_os, obj, FTAG, &bonus));
 488         dlp = bonus->db_data;
 489         dmu_buf_will_dirty(bonus, tx);
 490         bzero(dlp, sizeof (*dlp));
 491         dmu_buf_rele(bonus, FTAG);
 492 }
 493
 494 /*
 495  * Remove entries on dl that are >= mintxg, and put them on the bpobj.
 496  */
 497 void
 498 dsl_deadlist_move_bpobj(dsl_deadlist_t *dl, bpobj_t *bpo, uint64_t mintxg,
 499     dmu_tx_t *tx)
 500 {
 501         dsl_deadlist_entry_t dle_tofind;
 502         dsl_deadlist_entry_t *dle;
 503         avl_index_t where;
 504
 505         ASSERT(!dl->dl_oldfmt);
 506         dmu_buf_will_dirty(dl->dl_dbuf, tx);
 507         dsl_deadlist_load_tree(dl);
 508
 509         dle_tofind.dle_mintxg = mintxg;
 510         dle = avl_find(&dl->dl_tree, &dle_tofind, &where);
 511         if (dle == NULL)
 512                 dle = avl_nearest(&dl->dl_tree, where, AVL_AFTER);
 513         while (dle) {
 514                 uint64_t used, comp, uncomp;
 515                 dsl_deadlist_entry_t *dle_next;
 516
 517                 bpobj_enqueue_subobj(bpo, dle->dle_bpobj.bpo_object, tx);
 518
 519                 VERIFY3U(0, ==, bpobj_space(&dle->dle_bpobj,
 520                     &used, &comp, &uncomp));
 521                 mutex_enter(&dl->dl_lock);
 522                 ASSERT3U(dl->dl_phys->dl_used, >=, used);
 523                 ASSERT3U(dl->dl_phys->dl_comp, >=, comp);
 524                 ASSERT3U(dl->dl_phys->dl_uncomp, >=, uncomp);
 525                 dl->dl_phys->dl_used -= used;
 526                 dl->dl_phys->dl_comp -= comp;
 527                 dl->dl_phys->dl_uncomp -= uncomp;
 528                 mutex_exit(&dl->dl_lock);
 529
 530                 VERIFY3U(0, ==, zap_remove_int(dl->dl_os, dl->dl_object,
 531                     dle->dle_mintxg, tx));
 532
 533                 dle_next = AVL_NEXT(&dl->dl_tree, dle);
 534                 avl_remove(&dl->dl_tree, dle);
 535                 bpobj_close(&dle->dle_bpobj);
 536                 kmem_free(dle, sizeof (*dle));
 537                 dle = dle_next;
 538         }
 539 }