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 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 #include <sys/dmu.h> 29 #include <sys/dmu_impl.h> 30 #include <sys/dmu_tx.h> 31 #include <sys/dbuf.h> 32 #include <sys/dnode.h> 33 #include <sys/zfs_context.h> 34 #include <sys/dmu_objset.h> 35 #include <sys/dmu_traverse.h> 36 #include <sys/dsl_dataset.h> 37 #include <sys/dsl_dir.h> 38 #include <sys/dsl_pool.h> 39 #include <sys/dsl_synctask.h> 40 #include <sys/dsl_prop.h> 41 #include <sys/dmu_zfetch.h> 42 #include <sys/zfs_ioctl.h> 43 #include <sys/zap.h> 44 #include <sys/zio_checksum.h> 45 #ifdef _KERNEL 46 #include <sys/vmsystm.h> 47 #endif 48 49 const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES] = { 50 { byteswap_uint8_array, TRUE, "unallocated" }, 51 { zap_byteswap, TRUE, "object directory" }, 52 { byteswap_uint64_array, TRUE, "object array" }, 53 { byteswap_uint8_array, TRUE, "packed nvlist" }, 54 { byteswap_uint64_array, TRUE, "packed nvlist size" }, 55 { byteswap_uint64_array, TRUE, "bplist" }, 56 { byteswap_uint64_array, TRUE, "bplist header" }, 57 { byteswap_uint64_array, TRUE, "SPA space map header" }, 58 { byteswap_uint64_array, TRUE, "SPA space map" }, 59 { byteswap_uint64_array, TRUE, "ZIL intent log" }, 60 { dnode_buf_byteswap, TRUE, "DMU dnode" }, 61 { dmu_objset_byteswap, TRUE, "DMU objset" }, 62 { byteswap_uint64_array, TRUE, "DSL directory" }, 63 { zap_byteswap, TRUE, "DSL directory child map"}, 64 { zap_byteswap, TRUE, "DSL dataset snap map" }, 65 { zap_byteswap, TRUE, "DSL props" }, 66 { byteswap_uint64_array, TRUE, "DSL dataset" }, 67 { zfs_znode_byteswap, TRUE, "ZFS znode" }, 68 { zfs_acl_byteswap, TRUE, "ZFS ACL" }, 69 { byteswap_uint8_array, FALSE, "ZFS plain file" }, 70 { zap_byteswap, TRUE, "ZFS directory" }, 71 { zap_byteswap, TRUE, "ZFS master node" }, 72 { zap_byteswap, TRUE, "ZFS delete queue" }, 73 { byteswap_uint8_array, FALSE, "zvol object" }, 74 { zap_byteswap, TRUE, "zvol prop" }, 75 { byteswap_uint8_array, FALSE, "other uint8[]" }, 76 { byteswap_uint64_array, FALSE, "other uint64[]" }, 77 { zap_byteswap, TRUE, "other ZAP" }, 78 { zap_byteswap, TRUE, "persistent error log" }, 79 { byteswap_uint8_array, TRUE, "SPA history" }, 80 { byteswap_uint64_array, TRUE, "SPA history offsets" }, 81 }; 82 83 int 84 dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset, 85 void *tag, dmu_buf_t **dbp) 86 { 87 dnode_t *dn; 88 uint64_t blkid; 89 dmu_buf_impl_t *db; 90 int err; 91 92 err = dnode_hold(os->os, object, FTAG, &dn); 93 if (err) 94 return (err); 95 blkid = dbuf_whichblock(dn, offset); 96 rw_enter(&dn->dn_struct_rwlock, RW_READER); 97 db = dbuf_hold(dn, blkid, tag); 98 rw_exit(&dn->dn_struct_rwlock); 99 if (db == NULL) { 100 err = EIO; 101 } else { 102 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 103 if (err) { 104 dbuf_rele(db, tag); 105 db = NULL; 106 } 107 } 108 109 dnode_rele(dn, FTAG); 110 *dbp = &db->db; 111 return (err); 112 } 113 114 int 115 dmu_bonus_max(void) 116 { 117 return (DN_MAX_BONUSLEN); 118 } 119 120 /* 121 * returns ENOENT, EIO, or 0. 122 */ 123 int 124 dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **dbp) 125 { 126 dnode_t *dn; 127 int err, count; 128 dmu_buf_impl_t *db; 129 130 err = dnode_hold(os->os, object, FTAG, &dn); 131 if (err) 132 return (err); 133 134 rw_enter(&dn->dn_struct_rwlock, RW_READER); 135 if (dn->dn_bonus == NULL) { 136 rw_exit(&dn->dn_struct_rwlock); 137 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 138 if (dn->dn_bonus == NULL) 139 dn->dn_bonus = dbuf_create_bonus(dn); 140 } 141 db = dn->dn_bonus; 142 rw_exit(&dn->dn_struct_rwlock); 143 mutex_enter(&db->db_mtx); 144 count = refcount_add(&db->db_holds, tag); 145 mutex_exit(&db->db_mtx); 146 if (count == 1) 147 dnode_add_ref(dn, db); 148 dnode_rele(dn, FTAG); 149 150 VERIFY(0 == dbuf_read(db, NULL, DB_RF_MUST_SUCCEED)); 151 152 *dbp = &db->db; 153 return (0); 154 } 155 156 /* 157 * Note: longer-term, we should modify all of the dmu_buf_*() interfaces 158 * to take a held dnode rather than <os, object> -- the lookup is wasteful, 159 * and can induce severe lock contention when writing to several files 160 * whose dnodes are in the same block. 161 */ 162 static int 163 dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, 164 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp) 165 { 166 dmu_buf_t **dbp; 167 uint64_t blkid, nblks, i; 168 uint32_t flags; 169 int err; 170 zio_t *zio; 171 172 ASSERT(length <= DMU_MAX_ACCESS); 173 174 flags = DB_RF_CANFAIL | DB_RF_NEVERWAIT; 175 if (length > zfetch_array_rd_sz) 176 flags |= DB_RF_NOPREFETCH; 177 178 rw_enter(&dn->dn_struct_rwlock, RW_READER); 179 if (dn->dn_datablkshift) { 180 int blkshift = dn->dn_datablkshift; 181 nblks = (P2ROUNDUP(offset+length, 1ULL<<blkshift) - 182 P2ALIGN(offset, 1ULL<<blkshift)) >> blkshift; 183 } else { 184 ASSERT3U(offset + length, <=, dn->dn_datablksz); 185 nblks = 1; 186 } 187 dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_SLEEP); 188 189 zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, TRUE); 190 blkid = dbuf_whichblock(dn, offset); 191 for (i = 0; i < nblks; i++) { 192 dmu_buf_impl_t *db = dbuf_hold(dn, blkid+i, tag); 193 if (db == NULL) { 194 rw_exit(&dn->dn_struct_rwlock); 195 dmu_buf_rele_array(dbp, nblks, tag); 196 zio_nowait(zio); 197 return (EIO); 198 } 199 /* initiate async i/o */ 200 if (read) { 201 rw_exit(&dn->dn_struct_rwlock); 202 (void) dbuf_read(db, zio, flags); 203 rw_enter(&dn->dn_struct_rwlock, RW_READER); 204 } 205 dbp[i] = &db->db; 206 } 207 rw_exit(&dn->dn_struct_rwlock); 208 209 /* wait for async i/o */ 210 err = zio_wait(zio); 211 if (err) { 212 dmu_buf_rele_array(dbp, nblks, tag); 213 return (err); 214 } 215 216 /* wait for other io to complete */ 217 if (read) { 218 for (i = 0; i < nblks; i++) { 219 dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i]; 220 mutex_enter(&db->db_mtx); 221 while (db->db_state == DB_READ || 222 db->db_state == DB_FILL) 223 cv_wait(&db->db_changed, &db->db_mtx); 224 if (db->db_state == DB_UNCACHED) 225 err = EIO; 226 mutex_exit(&db->db_mtx); 227 if (err) { 228 dmu_buf_rele_array(dbp, nblks, tag); 229 return (err); 230 } 231 } 232 } 233 234 *numbufsp = nblks; 235 *dbpp = dbp; 236 return (0); 237 } 238 239 static int 240 dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset, 241 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp) 242 { 243 dnode_t *dn; 244 int err; 245 246 err = dnode_hold(os->os, object, FTAG, &dn); 247 if (err) 248 return (err); 249 250 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag, 251 numbufsp, dbpp); 252 253 dnode_rele(dn, FTAG); 254 255 return (err); 256 } 257 258 int 259 dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset, 260 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp) 261 { 262 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode; 263 int err; 264 265 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag, 266 numbufsp, dbpp); 267 268 return (err); 269 } 270 271 void 272 dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, void *tag) 273 { 274 int i; 275 dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake; 276 277 if (numbufs == 0) 278 return; 279 280 for (i = 0; i < numbufs; i++) { 281 if (dbp[i]) 282 dbuf_rele(dbp[i], tag); 283 } 284 285 kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs); 286 } 287 288 void 289 dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len) 290 { 291 dnode_t *dn; 292 uint64_t blkid; 293 int nblks, i, err; 294 295 if (zfs_prefetch_disable) 296 return; 297 298 if (len == 0) { /* they're interested in the bonus buffer */ 299 dn = os->os->os_meta_dnode; 300 301 if (object == 0 || object >= DN_MAX_OBJECT) 302 return; 303 304 rw_enter(&dn->dn_struct_rwlock, RW_READER); 305 blkid = dbuf_whichblock(dn, object * sizeof (dnode_phys_t)); 306 dbuf_prefetch(dn, blkid); 307 rw_exit(&dn->dn_struct_rwlock); 308 return; 309 } 310 311 /* 312 * XXX - Note, if the dnode for the requested object is not 313 * already cached, we will do a *synchronous* read in the 314 * dnode_hold() call. The same is true for any indirects. 315 */ 316 err = dnode_hold(os->os, object, FTAG, &dn); 317 if (err != 0) 318 return; 319 320 rw_enter(&dn->dn_struct_rwlock, RW_READER); 321 if (dn->dn_datablkshift) { 322 int blkshift = dn->dn_datablkshift; 323 nblks = (P2ROUNDUP(offset+len, 1<<blkshift) - 324 P2ALIGN(offset, 1<<blkshift)) >> blkshift; 325 } else { 326 nblks = (offset < dn->dn_datablksz); 327 } 328 329 if (nblks != 0) { 330 blkid = dbuf_whichblock(dn, offset); 331 for (i = 0; i < nblks; i++) 332 dbuf_prefetch(dn, blkid+i); 333 } 334 335 rw_exit(&dn->dn_struct_rwlock); 336 337 dnode_rele(dn, FTAG); 338 } 339 340 int 341 dmu_free_range(objset_t *os, uint64_t object, uint64_t offset, 342 uint64_t size, dmu_tx_t *tx) 343 { 344 dnode_t *dn; 345 int err = dnode_hold(os->os, object, FTAG, &dn); 346 if (err) 347 return (err); 348 ASSERT(offset < UINT64_MAX); 349 ASSERT(size == -1ULL || size <= UINT64_MAX - offset); 350 dnode_free_range(dn, offset, size, tx); 351 dnode_rele(dn, FTAG); 352 return (0); 353 } 354 355 int 356 dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 357 void *buf) 358 { 359 dnode_t *dn; 360 dmu_buf_t **dbp; 361 int numbufs, i, err; 362 363 /* 364 * Deal with odd block sizes, where there can't be data past the 365 * first block. 366 */ 367 err = dnode_hold(os->os, object, FTAG, &dn); 368 if (err) 369 return (err); 370 if (dn->dn_datablkshift == 0) { 371 int newsz = offset > dn->dn_datablksz ? 0 : 372 MIN(size, dn->dn_datablksz - offset); 373 bzero((char *)buf + newsz, size - newsz); 374 size = newsz; 375 } 376 377 while (size > 0) { 378 uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2); 379 int err; 380 381 /* 382 * NB: we could do this block-at-a-time, but it's nice 383 * to be reading in parallel. 384 */ 385 err = dmu_buf_hold_array_by_dnode(dn, offset, mylen, 386 TRUE, FTAG, &numbufs, &dbp); 387 if (err) 388 return (err); 389 390 for (i = 0; i < numbufs; i++) { 391 int tocpy; 392 int bufoff; 393 dmu_buf_t *db = dbp[i]; 394 395 ASSERT(size > 0); 396 397 bufoff = offset - db->db_offset; 398 tocpy = (int)MIN(db->db_size - bufoff, size); 399 400 bcopy((char *)db->db_data + bufoff, buf, tocpy); 401 402 offset += tocpy; 403 size -= tocpy; 404 buf = (char *)buf + tocpy; 405 } 406 dmu_buf_rele_array(dbp, numbufs, FTAG); 407 } 408 dnode_rele(dn, FTAG); 409 return (0); 410 } 411 412 void 413 dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 414 const void *buf, dmu_tx_t *tx) 415 { 416 dmu_buf_t **dbp; 417 int numbufs, i; 418 419 if (size == 0) 420 return; 421 422 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size, 423 FALSE, FTAG, &numbufs, &dbp)); 424 425 for (i = 0; i < numbufs; i++) { 426 int tocpy; 427 int bufoff; 428 dmu_buf_t *db = dbp[i]; 429 430 ASSERT(size > 0); 431 432 bufoff = offset - db->db_offset; 433 tocpy = (int)MIN(db->db_size - bufoff, size); 434 435 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 436 437 if (tocpy == db->db_size) 438 dmu_buf_will_fill(db, tx); 439 else 440 dmu_buf_will_dirty(db, tx); 441 442 bcopy(buf, (char *)db->db_data + bufoff, tocpy); 443 444 if (tocpy == db->db_size) 445 dmu_buf_fill_done(db, tx); 446 447 offset += tocpy; 448 size -= tocpy; 449 buf = (char *)buf + tocpy; 450 } 451 dmu_buf_rele_array(dbp, numbufs, FTAG); 452 } 453 454 #ifdef _KERNEL 455 int 456 dmu_write_uio(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 457 uio_t *uio, dmu_tx_t *tx) 458 { 459 dmu_buf_t **dbp; 460 int numbufs, i; 461 int err = 0; 462 463 if (size == 0) 464 return (0); 465 466 err = dmu_buf_hold_array(os, object, offset, size, 467 FALSE, FTAG, &numbufs, &dbp); 468 if (err) 469 return (err); 470 471 for (i = 0; i < numbufs; i++) { 472 int tocpy; 473 int bufoff; 474 dmu_buf_t *db = dbp[i]; 475 476 ASSERT(size > 0); 477 478 bufoff = offset - db->db_offset; 479 tocpy = (int)MIN(db->db_size - bufoff, size); 480 481 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 482 483 if (tocpy == db->db_size) 484 dmu_buf_will_fill(db, tx); 485 else 486 dmu_buf_will_dirty(db, tx); 487 488 /* 489 * XXX uiomove could block forever (eg. nfs-backed 490 * pages). There needs to be a uiolockdown() function 491 * to lock the pages in memory, so that uiomove won't 492 * block. 493 */ 494 err = uiomove((char *)db->db_data + bufoff, tocpy, 495 UIO_WRITE, uio); 496 497 if (tocpy == db->db_size) 498 dmu_buf_fill_done(db, tx); 499 500 if (err) 501 break; 502 503 offset += tocpy; 504 size -= tocpy; 505 } 506 dmu_buf_rele_array(dbp, numbufs, FTAG); 507 return (err); 508 } 509 510 int 511 dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 512 page_t *pp, dmu_tx_t *tx) 513 { 514 dmu_buf_t **dbp; 515 int numbufs, i; 516 int err; 517 518 if (size == 0) 519 return (0); 520 521 err = dmu_buf_hold_array(os, object, offset, size, 522 FALSE, FTAG, &numbufs, &dbp); 523 if (err) 524 return (err); 525 526 for (i = 0; i < numbufs; i++) { 527 int tocpy, copied, thiscpy; 528 int bufoff; 529 dmu_buf_t *db = dbp[i]; 530 caddr_t va; 531 532 ASSERT(size > 0); 533 ASSERT3U(db->db_size, >=, PAGESIZE); 534 535 bufoff = offset - db->db_offset; 536 tocpy = (int)MIN(db->db_size - bufoff, size); 537 538 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 539 540 if (tocpy == db->db_size) 541 dmu_buf_will_fill(db, tx); 542 else 543 dmu_buf_will_dirty(db, tx); 544 545 for (copied = 0; copied < tocpy; copied += PAGESIZE) { 546 ASSERT3U(pp->p_offset, ==, db->db_offset + bufoff); 547 thiscpy = MIN(PAGESIZE, tocpy - copied); 548 va = ppmapin(pp, PROT_READ, (caddr_t)-1); 549 bcopy(va, (char *)db->db_data + bufoff, thiscpy); 550 ppmapout(va); 551 pp = pp->p_next; 552 bufoff += PAGESIZE; 553 } 554 555 if (tocpy == db->db_size) 556 dmu_buf_fill_done(db, tx); 557 558 if (err) 559 break; 560 561 offset += tocpy; 562 size -= tocpy; 563 } 564 dmu_buf_rele_array(dbp, numbufs, FTAG); 565 return (err); 566 } 567 #endif 568 569 typedef struct { 570 dbuf_dirty_record_t *dr; 571 dmu_sync_cb_t *done; 572 void *arg; 573 } dmu_sync_arg_t; 574 575 /* ARGSUSED */ 576 static void 577 dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg) 578 { 579 dmu_sync_arg_t *in = varg; 580 dbuf_dirty_record_t *dr = in->dr; 581 dmu_buf_impl_t *db = dr->dr_dbuf; 582 dmu_sync_cb_t *done = in->done; 583 584 if (!BP_IS_HOLE(zio->io_bp)) { 585 zio->io_bp->blk_fill = 1; 586 BP_SET_TYPE(zio->io_bp, db->db_dnode->dn_type); 587 BP_SET_LEVEL(zio->io_bp, 0); 588 } 589 590 mutex_enter(&db->db_mtx); 591 ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC); 592 dr->dt.dl.dr_overridden_by = *zio->io_bp; /* structure assignment */ 593 dr->dt.dl.dr_override_state = DR_OVERRIDDEN; 594 cv_broadcast(&db->db_changed); 595 mutex_exit(&db->db_mtx); 596 597 if (done) 598 done(&(db->db), in->arg); 599 600 kmem_free(in, sizeof (dmu_sync_arg_t)); 601 } 602 603 /* 604 * Intent log support: sync the block associated with db to disk. 605 * N.B. and XXX: the caller is responsible for making sure that the 606 * data isn't changing while dmu_sync() is writing it. 607 * 608 * Return values: 609 * 610 * EEXIST: this txg has already been synced, so there's nothing to to. 611 * The caller should not log the write. 612 * 613 * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do. 614 * The caller should not log the write. 615 * 616 * EALREADY: this block is already in the process of being synced. 617 * The caller should track its progress (somehow). 618 * 619 * EINPROGRESS: the IO has been initiated. 620 * The caller should log this blkptr in the callback. 621 * 622 * 0: completed. Sets *bp to the blkptr just written. 623 * The caller should log this blkptr immediately. 624 */ 625 int 626 dmu_sync(zio_t *pio, dmu_buf_t *db_fake, 627 blkptr_t *bp, uint64_t txg, dmu_sync_cb_t *done, void *arg) 628 { 629 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 630 objset_impl_t *os = db->db_objset; 631 dsl_pool_t *dp = os->os_dsl_dataset->ds_dir->dd_pool; 632 tx_state_t *tx = &dp->dp_tx; 633 dbuf_dirty_record_t *dr; 634 dmu_sync_arg_t *in; 635 zbookmark_t zb; 636 zio_t *zio; 637 int err; 638 639 ASSERT(BP_IS_HOLE(bp)); 640 ASSERT(txg != 0); 641 642 643 dprintf("dmu_sync txg=%llu, s,o,q %llu %llu %llu\n", 644 txg, tx->tx_synced_txg, tx->tx_open_txg, tx->tx_quiesced_txg); 645 646 /* 647 * XXX - would be nice if we could do this without suspending... 648 */ 649 txg_suspend(dp); 650 651 /* 652 * If this txg already synced, there's nothing to do. 653 */ 654 if (txg <= tx->tx_synced_txg) { 655 txg_resume(dp); 656 /* 657 * If we're running ziltest, we need the blkptr regardless. 658 */ 659 if (txg > spa_freeze_txg(dp->dp_spa)) { 660 /* if db_blkptr == NULL, this was an empty write */ 661 if (db->db_blkptr) 662 *bp = *db->db_blkptr; /* structure assignment */ 663 return (0); 664 } 665 return (EEXIST); 666 } 667 668 mutex_enter(&db->db_mtx); 669 670 if (txg == tx->tx_syncing_txg) { 671 while (db->db_data_pending) { 672 /* 673 * IO is in-progress. Wait for it to finish. 674 * XXX - would be nice to be able to somehow "attach" 675 * this zio to the parent zio passed in. 676 */ 677 cv_wait(&db->db_changed, &db->db_mtx); 678 if (!db->db_data_pending && 679 db->db_blkptr && BP_IS_HOLE(db->db_blkptr)) { 680 /* 681 * IO was compressed away 682 */ 683 *bp = *db->db_blkptr; /* structure assignment */ 684 mutex_exit(&db->db_mtx); 685 txg_resume(dp); 686 return (0); 687 } 688 ASSERT(db->db_data_pending || 689 (db->db_blkptr && db->db_blkptr->blk_birth == txg)); 690 } 691 692 if (db->db_blkptr && db->db_blkptr->blk_birth == txg) { 693 /* 694 * IO is already completed. 695 */ 696 *bp = *db->db_blkptr; /* structure assignment */ 697 mutex_exit(&db->db_mtx); 698 txg_resume(dp); 699 return (0); 700 } 701 } 702 703 dr = db->db_last_dirty; 704 while (dr && dr->dr_txg > txg) 705 dr = dr->dr_next; 706 if (dr == NULL || dr->dr_txg < txg) { 707 /* 708 * This dbuf isn't dirty, must have been free_range'd. 709 * There's no need to log writes to freed blocks, so we're done. 710 */ 711 mutex_exit(&db->db_mtx); 712 txg_resume(dp); 713 return (ENOENT); 714 } 715 716 ASSERT(dr->dr_txg == txg); 717 if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC) { 718 /* 719 * We have already issued a sync write for this buffer. 720 */ 721 mutex_exit(&db->db_mtx); 722 txg_resume(dp); 723 return (EALREADY); 724 } else if (dr->dt.dl.dr_override_state == DR_OVERRIDDEN) { 725 /* 726 * This buffer has already been synced. It could not 727 * have been dirtied since, or we would have cleared the state. 728 */ 729 *bp = dr->dt.dl.dr_overridden_by; /* structure assignment */ 730 mutex_exit(&db->db_mtx); 731 txg_resume(dp); 732 return (0); 733 } 734 735 dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC; 736 in = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP); 737 in->dr = dr; 738 in->done = done; 739 in->arg = arg; 740 mutex_exit(&db->db_mtx); 741 txg_resume(dp); 742 743 zb.zb_objset = os->os_dsl_dataset->ds_object; 744 zb.zb_object = db->db.db_object; 745 zb.zb_level = db->db_level; 746 zb.zb_blkid = db->db_blkid; 747 zio = arc_write(pio, os->os_spa, 748 zio_checksum_select(db->db_dnode->dn_checksum, os->os_checksum), 749 zio_compress_select(db->db_dnode->dn_compress, os->os_compress), 750 dmu_get_replication_level(os->os_spa, &zb, db->db_dnode->dn_type), 751 txg, bp, dr->dt.dl.dr_data, NULL, dmu_sync_done, in, 752 ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_MUSTSUCCEED, &zb); 753 754 if (pio) { 755 zio_nowait(zio); 756 err = EINPROGRESS; 757 } else { 758 err = zio_wait(zio); 759 ASSERT(err == 0); 760 } 761 return (err); 762 } 763 764 int 765 dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs, 766 dmu_tx_t *tx) 767 { 768 dnode_t *dn; 769 int err; 770 771 err = dnode_hold(os->os, object, FTAG, &dn); 772 if (err) 773 return (err); 774 err = dnode_set_blksz(dn, size, ibs, tx); 775 dnode_rele(dn, FTAG); 776 return (err); 777 } 778 779 void 780 dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum, 781 dmu_tx_t *tx) 782 { 783 dnode_t *dn; 784 785 /* XXX assumes dnode_hold will not get an i/o error */ 786 (void) dnode_hold(os->os, object, FTAG, &dn); 787 ASSERT(checksum < ZIO_CHECKSUM_FUNCTIONS); 788 dn->dn_checksum = checksum; 789 dnode_setdirty(dn, tx); 790 dnode_rele(dn, FTAG); 791 } 792 793 void 794 dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress, 795 dmu_tx_t *tx) 796 { 797 dnode_t *dn; 798 799 /* XXX assumes dnode_hold will not get an i/o error */ 800 (void) dnode_hold(os->os, object, FTAG, &dn); 801 ASSERT(compress < ZIO_COMPRESS_FUNCTIONS); 802 dn->dn_compress = compress; 803 dnode_setdirty(dn, tx); 804 dnode_rele(dn, FTAG); 805 } 806 807 /* 808 * XXX - eventually, this should take into account per-dataset (or 809 * even per-object?) user requests for higher levels of replication. 810 */ 811 int 812 dmu_get_replication_level(spa_t *spa, zbookmark_t *zb, dmu_object_type_t ot) 813 { 814 int ncopies = 1; 815 816 if (dmu_ot[ot].ot_metadata) 817 ncopies++; 818 if (zb->zb_level != 0) 819 ncopies++; 820 if (zb->zb_objset == 0 && zb->zb_object == 0) 821 ncopies++; 822 return (MIN(ncopies, spa_max_replication(spa))); 823 } 824 825 int 826 dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off) 827 { 828 dnode_t *dn; 829 int i, err; 830 831 err = dnode_hold(os->os, object, FTAG, &dn); 832 if (err) 833 return (err); 834 /* 835 * Sync any current changes before 836 * we go trundling through the block pointers. 837 */ 838 for (i = 0; i < TXG_SIZE; i++) { 839 if (list_link_active(&dn->dn_dirty_link[i])) 840 break; 841 } 842 if (i != TXG_SIZE) { 843 dnode_rele(dn, FTAG); 844 txg_wait_synced(dmu_objset_pool(os), 0); 845 err = dnode_hold(os->os, object, FTAG, &dn); 846 if (err) 847 return (err); 848 } 849 850 err = dnode_next_offset(dn, hole, off, 1, 1, 0); 851 dnode_rele(dn, FTAG); 852 853 return (err); 854 } 855 856 void 857 dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi) 858 { 859 rw_enter(&dn->dn_struct_rwlock, RW_READER); 860 mutex_enter(&dn->dn_mtx); 861 862 doi->doi_data_block_size = dn->dn_datablksz; 863 doi->doi_metadata_block_size = dn->dn_indblkshift ? 864 1ULL << dn->dn_indblkshift : 0; 865 doi->doi_indirection = dn->dn_nlevels; 866 doi->doi_checksum = dn->dn_checksum; 867 doi->doi_compress = dn->dn_compress; 868 doi->doi_physical_blks = (DN_USED_BYTES(dn->dn_phys) + 869 SPA_MINBLOCKSIZE/2) >> SPA_MINBLOCKSHIFT; 870 doi->doi_max_block_offset = dn->dn_phys->dn_maxblkid; 871 doi->doi_type = dn->dn_type; 872 doi->doi_bonus_size = dn->dn_bonuslen; 873 doi->doi_bonus_type = dn->dn_bonustype; 874 875 mutex_exit(&dn->dn_mtx); 876 rw_exit(&dn->dn_struct_rwlock); 877 } 878 879 /* 880 * Get information on a DMU object. 881 * If doi is NULL, just indicates whether the object exists. 882 */ 883 int 884 dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi) 885 { 886 dnode_t *dn; 887 int err = dnode_hold(os->os, object, FTAG, &dn); 888 889 if (err) 890 return (err); 891 892 if (doi != NULL) 893 dmu_object_info_from_dnode(dn, doi); 894 895 dnode_rele(dn, FTAG); 896 return (0); 897 } 898 899 /* 900 * As above, but faster; can be used when you have a held dbuf in hand. 901 */ 902 void 903 dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi) 904 { 905 dmu_object_info_from_dnode(((dmu_buf_impl_t *)db)->db_dnode, doi); 906 } 907 908 /* 909 * Faster still when you only care about the size. 910 * This is specifically optimized for zfs_getattr(). 911 */ 912 void 913 dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize, u_longlong_t *nblk512) 914 { 915 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode; 916 917 *blksize = dn->dn_datablksz; 918 /* add 1 for dnode space */ 919 *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >> 920 SPA_MINBLOCKSHIFT) + 1; 921 } 922 923 void 924 byteswap_uint64_array(void *vbuf, size_t size) 925 { 926 uint64_t *buf = vbuf; 927 size_t count = size >> 3; 928 int i; 929 930 ASSERT((size & 7) == 0); 931 932 for (i = 0; i < count; i++) 933 buf[i] = BSWAP_64(buf[i]); 934 } 935 936 void 937 byteswap_uint32_array(void *vbuf, size_t size) 938 { 939 uint32_t *buf = vbuf; 940 size_t count = size >> 2; 941 int i; 942 943 ASSERT((size & 3) == 0); 944 945 for (i = 0; i < count; i++) 946 buf[i] = BSWAP_32(buf[i]); 947 } 948 949 void 950 byteswap_uint16_array(void *vbuf, size_t size) 951 { 952 uint16_t *buf = vbuf; 953 size_t count = size >> 1; 954 int i; 955 956 ASSERT((size & 1) == 0); 957 958 for (i = 0; i < count; i++) 959 buf[i] = BSWAP_16(buf[i]); 960 } 961 962 /* ARGSUSED */ 963 void 964 byteswap_uint8_array(void *vbuf, size_t size) 965 { 966 } 967 968 void 969 dmu_init(void) 970 { 971 dbuf_init(); 972 dnode_init(); 973 arc_init(); 974 } 975 976 void 977 dmu_fini(void) 978 { 979 arc_fini(); 980 dnode_fini(); 981 dbuf_fini(); 982 } 983