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 2008 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 #define SET_BOOKMARK(zb, objset, object, level, blkid) \ 39 { \ 40 (zb)->zb_objset = objset; \ 41 (zb)->zb_object = object; \ 42 (zb)->zb_level = level; \ 43 (zb)->zb_blkid = blkid; \ 44 } 45 46 struct prefetch_data { 47 kmutex_t pd_mtx; 48 kcondvar_t pd_cv; 49 int pd_blks_max; 50 int pd_blks_fetched; 51 int pd_flags; 52 boolean_t pd_cancel; 53 boolean_t pd_exited; 54 }; 55 56 struct traverse_data { 57 spa_t *td_spa; 58 uint64_t td_objset; 59 blkptr_t *td_rootbp; 60 uint64_t td_min_txg; 61 int td_flags; 62 struct prefetch_data *td_pfd; 63 blkptr_cb_t *td_func; 64 void *td_arg; 65 }; 66 67 /* ARGSUSED */ 68 static void 69 traverse_zil_block(zilog_t *zilog, blkptr_t *bp, void *arg, uint64_t claim_txg) 70 { 71 struct traverse_data *td = arg; 72 zbookmark_t zb; 73 74 if (bp->blk_birth == 0) 75 return; 76 77 if (claim_txg == 0 && bp->blk_birth >= spa_first_txg(td->td_spa)) 78 return; 79 80 zb.zb_objset = td->td_objset; 81 zb.zb_object = 0; 82 zb.zb_level = -1; 83 zb.zb_blkid = bp->blk_cksum.zc_word[ZIL_ZC_SEQ]; 84 VERIFY(0 == td->td_func(td->td_spa, bp, &zb, NULL, td->td_arg)); 85 } 86 87 /* ARGSUSED */ 88 static void 89 traverse_zil_record(zilog_t *zilog, lr_t *lrc, void *arg, uint64_t claim_txg) 90 { 91 struct traverse_data *td = arg; 92 93 if (lrc->lrc_txtype == TX_WRITE) { 94 lr_write_t *lr = (lr_write_t *)lrc; 95 blkptr_t *bp = &lr->lr_blkptr; 96 zbookmark_t zb; 97 98 if (bp->blk_birth == 0) 99 return; 100 101 if (claim_txg == 0 || bp->blk_birth < claim_txg) 102 return; 103 104 zb.zb_objset = td->td_objset; 105 zb.zb_object = lr->lr_foid; 106 zb.zb_level = BP_GET_LEVEL(bp); 107 zb.zb_blkid = lr->lr_offset / BP_GET_LSIZE(bp); 108 VERIFY(0 == td->td_func(td->td_spa, bp, &zb, NULL, td->td_arg)); 109 } 110 } 111 112 static void 113 traverse_zil(struct traverse_data *td, zil_header_t *zh) 114 { 115 uint64_t claim_txg = zh->zh_claim_txg; 116 zilog_t *zilog; 117 118 /* 119 * We only want to visit blocks that have been claimed but not yet 120 * replayed (or, in read-only mode, blocks that *would* be claimed). 121 */ 122 if (claim_txg == 0 && spa_writeable(td->td_spa)) 123 return; 124 125 zilog = zil_alloc(spa_get_dsl(td->td_spa)->dp_meta_objset, zh); 126 127 (void) zil_parse(zilog, traverse_zil_block, traverse_zil_record, td, 128 claim_txg); 129 130 zil_free(zilog); 131 } 132 133 static int 134 traverse_visitbp(struct traverse_data *td, const dnode_phys_t *dnp, 135 arc_buf_t *pbuf, blkptr_t *bp, const zbookmark_t *zb) 136 { 137 zbookmark_t czb; 138 int err = 0; 139 arc_buf_t *buf = NULL; 140 struct prefetch_data *pd = td->td_pfd; 141 142 if (bp->blk_birth == 0) { 143 err = td->td_func(td->td_spa, NULL, zb, dnp, 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, bp, zb, dnp, td->td_arg); 164 if (err) 165 return (err); 166 } 167 168 if (BP_GET_LEVEL(bp) > 0) { 169 uint32_t flags = ARC_WAIT; 170 int i; 171 blkptr_t *cbp; 172 int epb = BP_GET_LSIZE(bp) >> SPA_BLKPTRSHIFT; 173 174 err = arc_read(NULL, td->td_spa, bp, pbuf, 175 arc_getbuf_func, &buf, 176 ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); 177 if (err) 178 return (err); 179 180 /* recursively visitbp() blocks below this */ 181 cbp = buf->b_data; 182 for (i = 0; i < epb; i++, cbp++) { 183 SET_BOOKMARK(&czb, zb->zb_objset, zb->zb_object, 184 zb->zb_level - 1, 185 zb->zb_blkid * epb + i); 186 err = traverse_visitbp(td, dnp, buf, cbp, &czb); 187 if (err) 188 break; 189 } 190 } else if (BP_GET_TYPE(bp) == DMU_OT_DNODE) { 191 uint32_t flags = ARC_WAIT; 192 int i, j; 193 int epb = BP_GET_LSIZE(bp) >> DNODE_SHIFT; 194 195 err = arc_read(NULL, td->td_spa, bp, pbuf, 196 arc_getbuf_func, &buf, 197 ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); 198 if (err) 199 return (err); 200 201 /* recursively visitbp() blocks below this */ 202 dnp = buf->b_data; 203 for (i = 0; i < epb && err == 0; i++, dnp++) { 204 for (j = 0; j < dnp->dn_nblkptr; j++) { 205 SET_BOOKMARK(&czb, zb->zb_objset, 206 zb->zb_blkid * epb + i, 207 dnp->dn_nlevels - 1, j); 208 err = traverse_visitbp(td, dnp, buf, 209 (blkptr_t *)&dnp->dn_blkptr[j], &czb); 210 if (err) 211 break; 212 } 213 } 214 } else if (BP_GET_TYPE(bp) == DMU_OT_OBJSET) { 215 uint32_t flags = ARC_WAIT; 216 objset_phys_t *osp; 217 int j; 218 219 err = arc_read_nolock(NULL, td->td_spa, bp, 220 arc_getbuf_func, &buf, 221 ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); 222 if (err) 223 return (err); 224 225 osp = buf->b_data; 226 /* 227 * traverse_zil is just here for zdb's leak checking. 228 * For other consumers, there will be no ZIL blocks. 229 */ 230 traverse_zil(td, &osp->os_zil_header); 231 232 for (j = 0; j < osp->os_meta_dnode.dn_nblkptr; j++) { 233 SET_BOOKMARK(&czb, zb->zb_objset, 0, 234 osp->os_meta_dnode.dn_nlevels - 1, j); 235 err = traverse_visitbp(td, &osp->os_meta_dnode, buf, 236 (blkptr_t *)&osp->os_meta_dnode.dn_blkptr[j], 237 &czb); 238 if (err) 239 break; 240 } 241 } 242 243 if (buf) 244 (void) arc_buf_remove_ref(buf, &buf); 245 246 if (err == 0 && (td->td_flags & TRAVERSE_POST)) 247 err = td->td_func(td->td_spa, bp, zb, dnp, td->td_arg); 248 249 return (err); 250 } 251 252 /* ARGSUSED */ 253 static int 254 traverse_prefetcher(spa_t *spa, blkptr_t *bp, const zbookmark_t *zb, 255 const dnode_phys_t *dnp, void *arg) 256 { 257 struct prefetch_data *pfd = arg; 258 uint32_t aflags = ARC_NOWAIT | ARC_PREFETCH; 259 260 ASSERT(pfd->pd_blks_fetched >= 0); 261 if (pfd->pd_cancel) 262 return (EINTR); 263 264 if (bp == NULL || !((pfd->pd_flags & TRAVERSE_PREFETCH_DATA) || 265 BP_GET_TYPE(bp) == DMU_OT_DNODE || BP_GET_LEVEL(bp) > 0)) 266 return (0); 267 268 mutex_enter(&pfd->pd_mtx); 269 while (!pfd->pd_cancel && pfd->pd_blks_fetched >= pfd->pd_blks_max) 270 cv_wait(&pfd->pd_cv, &pfd->pd_mtx); 271 pfd->pd_blks_fetched++; 272 cv_broadcast(&pfd->pd_cv); 273 mutex_exit(&pfd->pd_mtx); 274 275 (void) arc_read_nolock(NULL, spa, bp, NULL, NULL, 276 ZIO_PRIORITY_ASYNC_READ, 277 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE, 278 &aflags, zb); 279 280 return (0); 281 } 282 283 static void 284 traverse_prefetch_thread(void *arg) 285 { 286 struct traverse_data *td_main = arg; 287 struct traverse_data td = *td_main; 288 zbookmark_t czb; 289 290 td.td_func = traverse_prefetcher; 291 td.td_arg = td_main->td_pfd; 292 td.td_pfd = NULL; 293 294 SET_BOOKMARK(&czb, td.td_objset, 0, -1, 0); 295 (void) traverse_visitbp(&td, NULL, NULL, td.td_rootbp, &czb); 296 297 mutex_enter(&td_main->td_pfd->pd_mtx); 298 td_main->td_pfd->pd_exited = B_TRUE; 299 cv_broadcast(&td_main->td_pfd->pd_cv); 300 mutex_exit(&td_main->td_pfd->pd_mtx); 301 } 302 303 /* 304 * NB: dataset must not be changing on-disk (eg, is a snapshot or we are 305 * in syncing context). 306 */ 307 static int 308 traverse_impl(spa_t *spa, uint64_t objset, blkptr_t *rootbp, 309 uint64_t txg_start, int flags, blkptr_cb_t func, void *arg) 310 { 311 struct traverse_data td; 312 struct prefetch_data pd = { 0 }; 313 zbookmark_t czb; 314 int err; 315 316 td.td_spa = spa; 317 td.td_objset = objset; 318 td.td_rootbp = rootbp; 319 td.td_min_txg = txg_start; 320 td.td_func = func; 321 td.td_arg = arg; 322 td.td_pfd = &pd; 323 td.td_flags = flags; 324 325 pd.pd_blks_max = 100; 326 pd.pd_flags = flags; 327 mutex_init(&pd.pd_mtx, NULL, MUTEX_DEFAULT, NULL); 328 cv_init(&pd.pd_cv, NULL, CV_DEFAULT, NULL); 329 330 if (!(flags & TRAVERSE_PREFETCH) || 331 0 == taskq_dispatch(system_taskq, traverse_prefetch_thread, 332 &td, TQ_NOQUEUE)) 333 pd.pd_exited = B_TRUE; 334 335 SET_BOOKMARK(&czb, objset, 0, -1, 0); 336 err = traverse_visitbp(&td, NULL, NULL, rootbp, &czb); 337 338 mutex_enter(&pd.pd_mtx); 339 pd.pd_cancel = B_TRUE; 340 cv_broadcast(&pd.pd_cv); 341 while (!pd.pd_exited) 342 cv_wait(&pd.pd_cv, &pd.pd_mtx); 343 mutex_exit(&pd.pd_mtx); 344 345 mutex_destroy(&pd.pd_mtx); 346 cv_destroy(&pd.pd_cv); 347 348 return (err); 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 int 356 traverse_dataset(dsl_dataset_t *ds, uint64_t txg_start, int flags, 357 blkptr_cb_t func, void *arg) 358 { 359 return (traverse_impl(ds->ds_dir->dd_pool->dp_spa, ds->ds_object, 360 &ds->ds_phys->ds_bp, txg_start, flags, func, arg)); 361 } 362 363 /* 364 * NB: pool must not be changing on-disk (eg, from zdb or sync context). 365 */ 366 int 367 traverse_pool(spa_t *spa, blkptr_cb_t func, void *arg) 368 { 369 int err; 370 uint64_t obj; 371 dsl_pool_t *dp = spa_get_dsl(spa); 372 objset_t *mos = dp->dp_meta_objset; 373 374 /* visit the MOS */ 375 err = traverse_impl(spa, 0, spa_get_rootblkptr(spa), 376 0, TRAVERSE_PRE, func, arg); 377 if (err) 378 return (err); 379 380 /* visit each dataset */ 381 for (obj = 1; err == 0; err = dmu_object_next(mos, &obj, FALSE, 0)) { 382 dmu_object_info_t doi; 383 384 err = dmu_object_info(mos, obj, &doi); 385 if (err) 386 return (err); 387 388 if (doi.doi_type == DMU_OT_DSL_DATASET) { 389 dsl_dataset_t *ds; 390 rw_enter(&dp->dp_config_rwlock, RW_READER); 391 err = dsl_dataset_hold_obj(dp, obj, FTAG, &ds); 392 rw_exit(&dp->dp_config_rwlock); 393 if (err) 394 return (err); 395 err = traverse_dataset(ds, 396 ds->ds_phys->ds_prev_snap_txg, TRAVERSE_PRE, 397 func, arg); 398 dsl_dataset_rele(ds, FTAG); 399 if (err) 400 return (err); 401 } 402 } 403 if (err == ESRCH) 404 err = 0; 405 return (err); 406 } 407