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/zfs_context.h> 26 #include <sys/dmu_objset.h> 27 #include <sys/dmu_traverse.h> 28 #include <sys/dsl_dataset.h> 29 #include <sys/dsl_dir.h> 30 #include <sys/dsl_pool.h> 31 #include <sys/dnode.h> 32 #include <sys/spa.h> 33 #include <sys/zio.h> 34 #include <sys/dmu_impl.h> 35 #include <sys/sa.h> 36 #include <sys/sa_impl.h> 37 #include <sys/callb.h> 38 39 int zfs_pd_blks_max = 100; 40 41 typedef struct prefetch_data { 42 kmutex_t pd_mtx; 43 kcondvar_t pd_cv; 44 int pd_blks_max; 45 int pd_blks_fetched; 46 int pd_flags; 47 boolean_t pd_cancel; 48 boolean_t pd_exited; 49 } prefetch_data_t; 50 51 typedef struct traverse_data { 52 spa_t *td_spa; 53 uint64_t td_objset; 54 blkptr_t *td_rootbp; 55 uint64_t td_min_txg; 56 int td_flags; 57 prefetch_data_t *td_pfd; 58 blkptr_cb_t *td_func; 59 void *td_arg; 60 } traverse_data_t; 61 62 static int traverse_dnode(traverse_data_t *td, const dnode_phys_t *dnp, 63 arc_buf_t *buf, uint64_t objset, uint64_t object); 64 65 static int 66 traverse_zil_block(zilog_t *zilog, blkptr_t *bp, void *arg, uint64_t claim_txg) 67 { 68 traverse_data_t *td = arg; 69 zbookmark_t zb; 70 71 if (bp->blk_birth == 0) 72 return (0); 73 74 if (claim_txg == 0 && bp->blk_birth >= spa_first_txg(td->td_spa)) 75 return (0); 76 77 SET_BOOKMARK(&zb, td->td_objset, ZB_ZIL_OBJECT, ZB_ZIL_LEVEL, 78 bp->blk_cksum.zc_word[ZIL_ZC_SEQ]); 79 80 (void) td->td_func(td->td_spa, zilog, bp, NULL, &zb, NULL, td->td_arg); 81 82 return (0); 83 } 84 85 static int 86 traverse_zil_record(zilog_t *zilog, lr_t *lrc, void *arg, uint64_t claim_txg) 87 { 88 traverse_data_t *td = arg; 89 90 if (lrc->lrc_txtype == TX_WRITE) { 91 lr_write_t *lr = (lr_write_t *)lrc; 92 blkptr_t *bp = &lr->lr_blkptr; 93 zbookmark_t zb; 94 95 if (bp->blk_birth == 0) 96 return (0); 97 98 if (claim_txg == 0 || bp->blk_birth < claim_txg) 99 return (0); 100 101 SET_BOOKMARK(&zb, td->td_objset, lr->lr_foid, 102 ZB_ZIL_LEVEL, lr->lr_offset / BP_GET_LSIZE(bp)); 103 104 (void) td->td_func(td->td_spa, zilog, bp, NULL, &zb, NULL, 105 td->td_arg); 106 } 107 return (0); 108 } 109 110 static void 111 traverse_zil(traverse_data_t *td, zil_header_t *zh) 112 { 113 uint64_t claim_txg = zh->zh_claim_txg; 114 zilog_t *zilog; 115 116 /* 117 * We only want to visit blocks that have been claimed but not yet 118 * replayed; plus, in read-only mode, blocks that are already stable. 119 */ 120 if (claim_txg == 0 && spa_writeable(td->td_spa)) 121 return; 122 123 zilog = zil_alloc(spa_get_dsl(td->td_spa)->dp_meta_objset, zh); 124 125 (void) zil_parse(zilog, traverse_zil_block, traverse_zil_record, td, 126 claim_txg); 127 128 zil_free(zilog); 129 } 130 131 static int 132 traverse_visitbp(traverse_data_t *td, const dnode_phys_t *dnp, 133 arc_buf_t *pbuf, blkptr_t *bp, const zbookmark_t *zb) 134 { 135 zbookmark_t czb; 136 int err = 0, lasterr = 0; 137 arc_buf_t *buf = NULL; 138 prefetch_data_t *pd = td->td_pfd; 139 boolean_t hard = td->td_flags & TRAVERSE_HARD; 140 141 if (bp->blk_birth == 0) { 142 err = td->td_func(td->td_spa, NULL, NULL, pbuf, zb, dnp, 143 td->td_arg); 144 return (err); 145 } 146 147 if (bp->blk_birth <= td->td_min_txg) 148 return (0); 149 150 if (pd && !pd->pd_exited && 151 ((pd->pd_flags & TRAVERSE_PREFETCH_DATA) || 152 BP_GET_TYPE(bp) == DMU_OT_DNODE || BP_GET_LEVEL(bp) > 0)) { 153 mutex_enter(&pd->pd_mtx); 154 ASSERT(pd->pd_blks_fetched >= 0); 155 while (pd->pd_blks_fetched == 0 && !pd->pd_exited) 156 cv_wait(&pd->pd_cv, &pd->pd_mtx); 157 pd->pd_blks_fetched--; 158 cv_broadcast(&pd->pd_cv); 159 mutex_exit(&pd->pd_mtx); 160 } 161 162 if (td->td_flags & TRAVERSE_PRE) { 163 err = td->td_func(td->td_spa, NULL, bp, pbuf, zb, dnp, 164 td->td_arg); 165 if (err == TRAVERSE_VISIT_NO_CHILDREN) 166 return (0); 167 if (err) 168 return (err); 169 } 170 171 if (BP_GET_LEVEL(bp) > 0) { 172 uint32_t flags = ARC_WAIT; 173 int i; 174 blkptr_t *cbp; 175 int epb = BP_GET_LSIZE(bp) >> SPA_BLKPTRSHIFT; 176 177 err = dsl_read(NULL, td->td_spa, bp, pbuf, 178 arc_getbuf_func, &buf, 179 ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); 180 if (err) 181 return (err); 182 183 /* recursively visitbp() blocks below this */ 184 cbp = buf->b_data; 185 for (i = 0; i < epb; i++, cbp++) { 186 SET_BOOKMARK(&czb, zb->zb_objset, zb->zb_object, 187 zb->zb_level - 1, 188 zb->zb_blkid * epb + i); 189 err = traverse_visitbp(td, dnp, buf, cbp, &czb); 190 if (err) { 191 if (!hard) 192 break; 193 lasterr = err; 194 } 195 } 196 } else if (BP_GET_TYPE(bp) == DMU_OT_DNODE) { 197 uint32_t flags = ARC_WAIT; 198 int i; 199 int epb = BP_GET_LSIZE(bp) >> DNODE_SHIFT; 200 201 err = dsl_read(NULL, td->td_spa, bp, pbuf, 202 arc_getbuf_func, &buf, 203 ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); 204 if (err) 205 return (err); 206 207 /* recursively visitbp() blocks below this */ 208 dnp = buf->b_data; 209 for (i = 0; i < epb; i++, dnp++) { 210 err = traverse_dnode(td, dnp, buf, zb->zb_objset, 211 zb->zb_blkid * epb + i); 212 if (err) { 213 if (!hard) 214 break; 215 lasterr = err; 216 } 217 } 218 } else if (BP_GET_TYPE(bp) == DMU_OT_OBJSET) { 219 uint32_t flags = ARC_WAIT; 220 objset_phys_t *osp; 221 dnode_phys_t *dnp; 222 223 err = dsl_read_nolock(NULL, td->td_spa, bp, 224 arc_getbuf_func, &buf, 225 ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); 226 if (err) 227 return (err); 228 229 osp = buf->b_data; 230 dnp = &osp->os_meta_dnode; 231 err = traverse_dnode(td, dnp, buf, zb->zb_objset, 232 DMU_META_DNODE_OBJECT); 233 if (err && hard) { 234 lasterr = err; 235 err = 0; 236 } 237 if (err == 0 && arc_buf_size(buf) >= sizeof (objset_phys_t)) { 238 dnp = &osp->os_userused_dnode; 239 err = traverse_dnode(td, dnp, buf, zb->zb_objset, 240 DMU_USERUSED_OBJECT); 241 } 242 if (err && hard) { 243 lasterr = err; 244 err = 0; 245 } 246 if (err == 0 && arc_buf_size(buf) >= sizeof (objset_phys_t)) { 247 dnp = &osp->os_groupused_dnode; 248 err = traverse_dnode(td, dnp, buf, zb->zb_objset, 249 DMU_GROUPUSED_OBJECT); 250 } 251 } 252 253 if (buf) 254 (void) arc_buf_remove_ref(buf, &buf); 255 256 if (err == 0 && lasterr == 0 && (td->td_flags & TRAVERSE_POST)) { 257 err = td->td_func(td->td_spa, NULL, bp, pbuf, zb, dnp, 258 td->td_arg); 259 } 260 261 return (err != 0 ? err : lasterr); 262 } 263 264 static int 265 traverse_dnode(traverse_data_t *td, const dnode_phys_t *dnp, 266 arc_buf_t *buf, uint64_t objset, uint64_t object) 267 { 268 int j, err = 0, lasterr = 0; 269 zbookmark_t czb; 270 boolean_t hard = (td->td_flags & TRAVERSE_HARD); 271 272 for (j = 0; j < dnp->dn_nblkptr; j++) { 273 SET_BOOKMARK(&czb, objset, object, dnp->dn_nlevels - 1, j); 274 err = traverse_visitbp(td, dnp, buf, 275 (blkptr_t *)&dnp->dn_blkptr[j], &czb); 276 if (err) { 277 if (!hard) 278 break; 279 lasterr = err; 280 } 281 } 282 283 if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { 284 SET_BOOKMARK(&czb, objset, 285 object, 0, DMU_SPILL_BLKID); 286 err = traverse_visitbp(td, dnp, buf, 287 (blkptr_t *)&dnp->dn_spill, &czb); 288 if (err) { 289 if (!hard) 290 return (err); 291 lasterr = err; 292 } 293 } 294 return (err != 0 ? err : lasterr); 295 } 296 297 /* ARGSUSED */ 298 static int 299 traverse_prefetcher(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, 300 arc_buf_t *pbuf, const zbookmark_t *zb, const dnode_phys_t *dnp, 301 void *arg) 302 { 303 prefetch_data_t *pfd = arg; 304 uint32_t aflags = ARC_NOWAIT | ARC_PREFETCH; 305 306 ASSERT(pfd->pd_blks_fetched >= 0); 307 if (pfd->pd_cancel) 308 return (EINTR); 309 310 if (bp == NULL || !((pfd->pd_flags & TRAVERSE_PREFETCH_DATA) || 311 BP_GET_TYPE(bp) == DMU_OT_DNODE || BP_GET_LEVEL(bp) > 0) || 312 BP_GET_TYPE(bp) == DMU_OT_INTENT_LOG) 313 return (0); 314 315 mutex_enter(&pfd->pd_mtx); 316 while (!pfd->pd_cancel && pfd->pd_blks_fetched >= pfd->pd_blks_max) 317 cv_wait(&pfd->pd_cv, &pfd->pd_mtx); 318 pfd->pd_blks_fetched++; 319 cv_broadcast(&pfd->pd_cv); 320 mutex_exit(&pfd->pd_mtx); 321 322 (void) dsl_read(NULL, spa, bp, pbuf, NULL, NULL, 323 ZIO_PRIORITY_ASYNC_READ, 324 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE, 325 &aflags, zb); 326 327 return (0); 328 } 329 330 static void 331 traverse_prefetch_thread(void *arg) 332 { 333 traverse_data_t *td_main = arg; 334 traverse_data_t td = *td_main; 335 zbookmark_t czb; 336 337 td.td_func = traverse_prefetcher; 338 td.td_arg = td_main->td_pfd; 339 td.td_pfd = NULL; 340 341 SET_BOOKMARK(&czb, td.td_objset, 342 ZB_ROOT_OBJECT, ZB_ROOT_LEVEL, ZB_ROOT_BLKID); 343 (void) traverse_visitbp(&td, NULL, NULL, td.td_rootbp, &czb); 344 345 mutex_enter(&td_main->td_pfd->pd_mtx); 346 td_main->td_pfd->pd_exited = B_TRUE; 347 cv_broadcast(&td_main->td_pfd->pd_cv); 348 mutex_exit(&td_main->td_pfd->pd_mtx); 349 } 350 351 /* 352 * NB: dataset must not be changing on-disk (eg, is a snapshot or we are 353 * in syncing context). 354 */ 355 static int 356 traverse_impl(spa_t *spa, dsl_dataset_t *ds, blkptr_t *rootbp, 357 uint64_t txg_start, int flags, blkptr_cb_t func, void *arg) 358 { 359 traverse_data_t td; 360 prefetch_data_t pd = { 0 }; 361 zbookmark_t czb; 362 int err; 363 364 td.td_spa = spa; 365 td.td_objset = ds ? ds->ds_object : 0; 366 td.td_rootbp = rootbp; 367 td.td_min_txg = txg_start; 368 td.td_func = func; 369 td.td_arg = arg; 370 td.td_pfd = &pd; 371 td.td_flags = flags; 372 373 pd.pd_blks_max = zfs_pd_blks_max; 374 pd.pd_flags = flags; 375 mutex_init(&pd.pd_mtx, NULL, MUTEX_DEFAULT, NULL); 376 cv_init(&pd.pd_cv, NULL, CV_DEFAULT, NULL); 377 378 /* See comment on ZIL traversal in dsl_scan_visitds. */ 379 if (ds != NULL && !dsl_dataset_is_snapshot(ds)) { 380 objset_t *os; 381 382 err = dmu_objset_from_ds(ds, &os); 383 if (err) 384 return (err); 385 386 traverse_zil(&td, &os->os_zil_header); 387 } 388 389 if (!(flags & TRAVERSE_PREFETCH) || 390 0 == taskq_dispatch(system_taskq, traverse_prefetch_thread, 391 &td, TQ_NOQUEUE)) 392 pd.pd_exited = B_TRUE; 393 394 SET_BOOKMARK(&czb, td.td_objset, 395 ZB_ROOT_OBJECT, ZB_ROOT_LEVEL, ZB_ROOT_BLKID); 396 err = traverse_visitbp(&td, NULL, NULL, rootbp, &czb); 397 398 mutex_enter(&pd.pd_mtx); 399 pd.pd_cancel = B_TRUE; 400 cv_broadcast(&pd.pd_cv); 401 while (!pd.pd_exited) 402 cv_wait(&pd.pd_cv, &pd.pd_mtx); 403 mutex_exit(&pd.pd_mtx); 404 405 mutex_destroy(&pd.pd_mtx); 406 cv_destroy(&pd.pd_cv); 407 408 return (err); 409 } 410 411 /* 412 * NB: dataset must not be changing on-disk (eg, is a snapshot or we are 413 * in syncing context). 414 */ 415 int 416 traverse_dataset(dsl_dataset_t *ds, uint64_t txg_start, int flags, 417 blkptr_cb_t func, void *arg) 418 { 419 return (traverse_impl(ds->ds_dir->dd_pool->dp_spa, ds, 420 &ds->ds_phys->ds_bp, txg_start, flags, func, arg)); 421 } 422 423 /* 424 * NB: pool must not be changing on-disk (eg, from zdb or sync context). 425 */ 426 int 427 traverse_pool(spa_t *spa, uint64_t txg_start, int flags, 428 blkptr_cb_t func, void *arg) 429 { 430 int err, lasterr = 0; 431 uint64_t obj; 432 dsl_pool_t *dp = spa_get_dsl(spa); 433 objset_t *mos = dp->dp_meta_objset; 434 boolean_t hard = (flags & TRAVERSE_HARD); 435 436 /* visit the MOS */ 437 err = traverse_impl(spa, NULL, spa_get_rootblkptr(spa), 438 txg_start, flags, func, arg); 439 if (err) 440 return (err); 441 442 /* visit each dataset */ 443 for (obj = 1; err == 0 || (err != ESRCH && hard); 444 err = dmu_object_next(mos, &obj, FALSE, txg_start)) { 445 dmu_object_info_t doi; 446 447 err = dmu_object_info(mos, obj, &doi); 448 if (err) { 449 if (!hard) 450 return (err); 451 lasterr = err; 452 continue; 453 } 454 455 if (doi.doi_type == DMU_OT_DSL_DATASET) { 456 dsl_dataset_t *ds; 457 uint64_t txg = txg_start; 458 459 rw_enter(&dp->dp_config_rwlock, RW_READER); 460 err = dsl_dataset_hold_obj(dp, obj, FTAG, &ds); 461 rw_exit(&dp->dp_config_rwlock); 462 if (err) { 463 if (!hard) 464 return (err); 465 lasterr = err; 466 continue; 467 } 468 if (ds->ds_phys->ds_prev_snap_txg > txg) 469 txg = ds->ds_phys->ds_prev_snap_txg; 470 err = traverse_dataset(ds, txg, flags, func, arg); 471 dsl_dataset_rele(ds, FTAG); 472 if (err) { 473 if (!hard) 474 return (err); 475 lasterr = err; 476 } 477 } 478 } 479 if (err == ESRCH) 480 err = 0; 481 return (err != 0 ? err : lasterr); 482 } 483