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 2009 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #include <sys/zfs_context.h> 27 #include <sys/dmu_objset.h> 28 #include <sys/dmu_traverse.h> 29 #include <sys/dsl_dataset.h> 30 #include <sys/dsl_dir.h> 31 #include <sys/dsl_pool.h> 32 #include <sys/dnode.h> 33 #include <sys/spa.h> 34 #include <sys/zio.h> 35 #include <sys/dmu_impl.h> 36 #include <sys/callb.h> 37 38 struct prefetch_data { 39 kmutex_t pd_mtx; 40 kcondvar_t pd_cv; 41 int pd_blks_max; 42 int pd_blks_fetched; 43 int pd_flags; 44 boolean_t pd_cancel; 45 boolean_t pd_exited; 46 }; 47 48 struct traverse_data { 49 spa_t *td_spa; 50 uint64_t td_objset; 51 blkptr_t *td_rootbp; 52 uint64_t td_min_txg; 53 int td_flags; 54 struct prefetch_data *td_pfd; 55 blkptr_cb_t *td_func; 56 void *td_arg; 57 }; 58 59 static int traverse_dnode(struct traverse_data *td, const dnode_phys_t *dnp, 60 arc_buf_t *buf, uint64_t objset, uint64_t object); 61 62 /* ARGSUSED */ 63 static int 64 traverse_zil_block(zilog_t *zilog, blkptr_t *bp, void *arg, uint64_t claim_txg) 65 { 66 struct traverse_data *td = arg; 67 zbookmark_t zb; 68 69 if (bp->blk_birth == 0) 70 return (0); 71 72 if (claim_txg == 0 && bp->blk_birth >= spa_first_txg(td->td_spa)) 73 return (0); 74 75 SET_BOOKMARK(&zb, td->td_objset, ZB_ZIL_OBJECT, ZB_ZIL_LEVEL, 76 bp->blk_cksum.zc_word[ZIL_ZC_SEQ]); 77 78 (void) td->td_func(td->td_spa, zilog, bp, &zb, NULL, td->td_arg); 79 80 return (0); 81 } 82 83 /* ARGSUSED */ 84 static int 85 traverse_zil_record(zilog_t *zilog, lr_t *lrc, void *arg, uint64_t claim_txg) 86 { 87 struct traverse_data *td = arg; 88 89 if (lrc->lrc_txtype == TX_WRITE) { 90 lr_write_t *lr = (lr_write_t *)lrc; 91 blkptr_t *bp = &lr->lr_blkptr; 92 zbookmark_t zb; 93 94 if (bp->blk_birth == 0) 95 return (0); 96 97 if (claim_txg == 0 || bp->blk_birth < claim_txg) 98 return (0); 99 100 SET_BOOKMARK(&zb, td->td_objset, lr->lr_foid, ZB_ZIL_LEVEL, 101 lr->lr_offset / BP_GET_LSIZE(bp)); 102 103 (void) td->td_func(td->td_spa, zilog, bp, &zb, NULL, 104 td->td_arg); 105 } 106 return (0); 107 } 108 109 static void 110 traverse_zil(struct traverse_data *td, zil_header_t *zh) 111 { 112 uint64_t claim_txg = zh->zh_claim_txg; 113 zilog_t *zilog; 114 115 /* 116 * We only want to visit blocks that have been claimed but not yet 117 * replayed; plus, in read-only mode, blocks that are already stable. 118 */ 119 if (claim_txg == 0 && spa_writeable(td->td_spa)) 120 return; 121 122 zilog = zil_alloc(spa_get_dsl(td->td_spa)->dp_meta_objset, zh); 123 124 (void) zil_parse(zilog, traverse_zil_block, traverse_zil_record, td, 125 claim_txg); 126 127 zil_free(zilog); 128 } 129 130 static int 131 traverse_visitbp(struct traverse_data *td, const dnode_phys_t *dnp, 132 arc_buf_t *pbuf, blkptr_t *bp, const zbookmark_t *zb) 133 { 134 zbookmark_t czb; 135 int err = 0; 136 arc_buf_t *buf = NULL; 137 struct prefetch_data *pd = td->td_pfd; 138 139 if (bp->blk_birth == 0) { 140 err = td->td_func(td->td_spa, NULL, NULL, zb, dnp, td->td_arg); 141 return (err); 142 } 143 144 if (bp->blk_birth <= td->td_min_txg) 145 return (0); 146 147 if (pd && !pd->pd_exited && 148 ((pd->pd_flags & TRAVERSE_PREFETCH_DATA) || 149 BP_GET_TYPE(bp) == DMU_OT_DNODE || BP_GET_LEVEL(bp) > 0)) { 150 mutex_enter(&pd->pd_mtx); 151 ASSERT(pd->pd_blks_fetched >= 0); 152 while (pd->pd_blks_fetched == 0 && !pd->pd_exited) 153 cv_wait(&pd->pd_cv, &pd->pd_mtx); 154 pd->pd_blks_fetched--; 155 cv_broadcast(&pd->pd_cv); 156 mutex_exit(&pd->pd_mtx); 157 } 158 159 if (td->td_flags & TRAVERSE_PRE) { 160 err = td->td_func(td->td_spa, NULL, bp, zb, dnp, td->td_arg); 161 if (err) 162 return (err); 163 } 164 165 if (BP_GET_LEVEL(bp) > 0) { 166 uint32_t flags = ARC_WAIT; 167 int i; 168 blkptr_t *cbp; 169 int epb = BP_GET_LSIZE(bp) >> SPA_BLKPTRSHIFT; 170 171 err = arc_read(NULL, td->td_spa, bp, pbuf, 172 arc_getbuf_func, &buf, 173 ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); 174 if (err) 175 return (err); 176 177 /* recursively visitbp() blocks below this */ 178 cbp = buf->b_data; 179 for (i = 0; i < epb; i++, cbp++) { 180 SET_BOOKMARK(&czb, zb->zb_objset, zb->zb_object, 181 zb->zb_level - 1, 182 zb->zb_blkid * epb + i); 183 err = traverse_visitbp(td, dnp, buf, cbp, &czb); 184 if (err) 185 break; 186 } 187 } else if (BP_GET_TYPE(bp) == DMU_OT_DNODE) { 188 uint32_t flags = ARC_WAIT; 189 int i; 190 int epb = BP_GET_LSIZE(bp) >> DNODE_SHIFT; 191 192 err = arc_read(NULL, td->td_spa, bp, pbuf, 193 arc_getbuf_func, &buf, 194 ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); 195 if (err) 196 return (err); 197 198 /* recursively visitbp() blocks below this */ 199 dnp = buf->b_data; 200 for (i = 0; i < epb && err == 0; i++, dnp++) { 201 err = traverse_dnode(td, dnp, buf, zb->zb_objset, 202 zb->zb_blkid * epb + i); 203 if (err) 204 break; 205 } 206 } else if (BP_GET_TYPE(bp) == DMU_OT_OBJSET) { 207 uint32_t flags = ARC_WAIT; 208 objset_phys_t *osp; 209 dnode_phys_t *dnp; 210 211 err = arc_read_nolock(NULL, td->td_spa, bp, 212 arc_getbuf_func, &buf, 213 ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); 214 if (err) 215 return (err); 216 217 osp = buf->b_data; 218 traverse_zil(td, &osp->os_zil_header); 219 220 dnp = &osp->os_meta_dnode; 221 err = traverse_dnode(td, dnp, buf, zb->zb_objset, 222 DMU_META_DNODE_OBJECT); 223 if (err == 0 && arc_buf_size(buf) >= sizeof (objset_phys_t)) { 224 dnp = &osp->os_userused_dnode; 225 err = traverse_dnode(td, dnp, buf, zb->zb_objset, 226 DMU_USERUSED_OBJECT); 227 } 228 if (err == 0 && arc_buf_size(buf) >= sizeof (objset_phys_t)) { 229 dnp = &osp->os_groupused_dnode; 230 err = traverse_dnode(td, dnp, buf, zb->zb_objset, 231 DMU_GROUPUSED_OBJECT); 232 } 233 } 234 235 if (buf) 236 (void) arc_buf_remove_ref(buf, &buf); 237 238 if (err == 0 && (td->td_flags & TRAVERSE_POST)) 239 err = td->td_func(td->td_spa, NULL, bp, zb, dnp, td->td_arg); 240 241 return (err); 242 } 243 244 static int 245 traverse_dnode(struct traverse_data *td, const dnode_phys_t *dnp, 246 arc_buf_t *buf, uint64_t objset, uint64_t object) 247 { 248 int j, err = 0; 249 zbookmark_t czb; 250 251 for (j = 0; j < dnp->dn_nblkptr; j++) { 252 SET_BOOKMARK(&czb, objset, object, dnp->dn_nlevels - 1, j); 253 err = traverse_visitbp(td, dnp, buf, 254 (blkptr_t *)&dnp->dn_blkptr[j], &czb); 255 if (err) 256 break; 257 } 258 return (err); 259 } 260 261 /* ARGSUSED */ 262 static int 263 traverse_prefetcher(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, 264 const zbookmark_t *zb, const dnode_phys_t *dnp, void *arg) 265 { 266 struct prefetch_data *pfd = arg; 267 uint32_t aflags = ARC_NOWAIT | ARC_PREFETCH; 268 269 ASSERT(pfd->pd_blks_fetched >= 0); 270 if (pfd->pd_cancel) 271 return (EINTR); 272 273 if (bp == NULL || !((pfd->pd_flags & TRAVERSE_PREFETCH_DATA) || 274 BP_GET_TYPE(bp) == DMU_OT_DNODE || BP_GET_LEVEL(bp) > 0)) 275 return (0); 276 277 mutex_enter(&pfd->pd_mtx); 278 while (!pfd->pd_cancel && pfd->pd_blks_fetched >= pfd->pd_blks_max) 279 cv_wait(&pfd->pd_cv, &pfd->pd_mtx); 280 pfd->pd_blks_fetched++; 281 cv_broadcast(&pfd->pd_cv); 282 mutex_exit(&pfd->pd_mtx); 283 284 (void) arc_read_nolock(NULL, spa, bp, NULL, NULL, 285 ZIO_PRIORITY_ASYNC_READ, 286 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE, 287 &aflags, zb); 288 289 return (0); 290 } 291 292 static void 293 traverse_prefetch_thread(void *arg) 294 { 295 struct traverse_data *td_main = arg; 296 struct traverse_data td = *td_main; 297 zbookmark_t czb; 298 299 td.td_func = traverse_prefetcher; 300 td.td_arg = td_main->td_pfd; 301 td.td_pfd = NULL; 302 303 SET_BOOKMARK(&czb, td.td_objset, 304 ZB_ROOT_OBJECT, ZB_ROOT_LEVEL, ZB_ROOT_BLKID); 305 (void) traverse_visitbp(&td, NULL, NULL, td.td_rootbp, &czb); 306 307 mutex_enter(&td_main->td_pfd->pd_mtx); 308 td_main->td_pfd->pd_exited = B_TRUE; 309 cv_broadcast(&td_main->td_pfd->pd_cv); 310 mutex_exit(&td_main->td_pfd->pd_mtx); 311 } 312 313 /* 314 * NB: dataset must not be changing on-disk (eg, is a snapshot or we are 315 * in syncing context). 316 */ 317 static int 318 traverse_impl(spa_t *spa, uint64_t objset, blkptr_t *rootbp, 319 uint64_t txg_start, int flags, blkptr_cb_t func, void *arg) 320 { 321 struct traverse_data td; 322 struct prefetch_data pd = { 0 }; 323 zbookmark_t czb; 324 int err; 325 326 td.td_spa = spa; 327 td.td_objset = objset; 328 td.td_rootbp = rootbp; 329 td.td_min_txg = txg_start; 330 td.td_func = func; 331 td.td_arg = arg; 332 td.td_pfd = &pd; 333 td.td_flags = flags; 334 335 pd.pd_blks_max = 100; 336 pd.pd_flags = flags; 337 mutex_init(&pd.pd_mtx, NULL, MUTEX_DEFAULT, NULL); 338 cv_init(&pd.pd_cv, NULL, CV_DEFAULT, NULL); 339 340 if (!(flags & TRAVERSE_PREFETCH) || 341 0 == taskq_dispatch(system_taskq, traverse_prefetch_thread, 342 &td, TQ_NOQUEUE)) 343 pd.pd_exited = B_TRUE; 344 345 SET_BOOKMARK(&czb, objset, 346 ZB_ROOT_OBJECT, ZB_ROOT_LEVEL, ZB_ROOT_BLKID); 347 err = traverse_visitbp(&td, NULL, NULL, rootbp, &czb); 348 349 mutex_enter(&pd.pd_mtx); 350 pd.pd_cancel = B_TRUE; 351 cv_broadcast(&pd.pd_cv); 352 while (!pd.pd_exited) 353 cv_wait(&pd.pd_cv, &pd.pd_mtx); 354 mutex_exit(&pd.pd_mtx); 355 356 mutex_destroy(&pd.pd_mtx); 357 cv_destroy(&pd.pd_cv); 358 359 return (err); 360 } 361 362 /* 363 * NB: dataset must not be changing on-disk (eg, is a snapshot or we are 364 * in syncing context). 365 */ 366 int 367 traverse_dataset(dsl_dataset_t *ds, uint64_t txg_start, int flags, 368 blkptr_cb_t func, void *arg) 369 { 370 return (traverse_impl(ds->ds_dir->dd_pool->dp_spa, ds->ds_object, 371 &ds->ds_phys->ds_bp, txg_start, flags, func, arg)); 372 } 373 374 /* 375 * NB: pool must not be changing on-disk (eg, from zdb or sync context). 376 */ 377 int 378 traverse_pool(spa_t *spa, uint64_t txg_start, int flags, 379 blkptr_cb_t func, void *arg) 380 { 381 int err; 382 uint64_t obj; 383 dsl_pool_t *dp = spa_get_dsl(spa); 384 objset_t *mos = dp->dp_meta_objset; 385 386 /* visit the MOS */ 387 err = traverse_impl(spa, 0, spa_get_rootblkptr(spa), 388 txg_start, flags, func, arg); 389 if (err) 390 return (err); 391 392 /* visit each dataset */ 393 for (obj = 1; err == 0; err = dmu_object_next(mos, &obj, FALSE, 394 txg_start)) { 395 dmu_object_info_t doi; 396 397 err = dmu_object_info(mos, obj, &doi); 398 if (err) 399 return (err); 400 401 if (doi.doi_type == DMU_OT_DSL_DATASET) { 402 dsl_dataset_t *ds; 403 uint64_t txg = txg_start; 404 405 rw_enter(&dp->dp_config_rwlock, RW_READER); 406 err = dsl_dataset_hold_obj(dp, obj, FTAG, &ds); 407 rw_exit(&dp->dp_config_rwlock); 408 if (err) 409 return (err); 410 if (ds->ds_phys->ds_prev_snap_txg > txg) 411 txg = ds->ds_phys->ds_prev_snap_txg; 412 err = traverse_dataset(ds, txg, flags, func, arg); 413 dsl_dataset_rele(ds, FTAG); 414 if (err) 415 return (err); 416 } 417 } 418 if (err == ESRCH) 419 err = 0; 420 return (err); 421 } 422