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