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 if (offset + length > dn->dn_datablksz) { 185 zfs_panic_recover("zfs: accessing past end of object " 186 "%llx/%llx (size=%u access=%llu+%llu)", 187 (longlong_t)dn->dn_objset-> 188 os_dsl_dataset->ds_object, 189 (longlong_t)dn->dn_object, dn->dn_datablksz, 190 (longlong_t)offset, (longlong_t)length); 191 return (EIO); 192 } 193 nblks = 1; 194 } 195 dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_SLEEP); 196 197 zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, TRUE); 198 blkid = dbuf_whichblock(dn, offset); 199 for (i = 0; i < nblks; i++) { 200 dmu_buf_impl_t *db = dbuf_hold(dn, blkid+i, tag); 201 if (db == NULL) { 202 rw_exit(&dn->dn_struct_rwlock); 203 dmu_buf_rele_array(dbp, nblks, tag); 204 zio_nowait(zio); 205 return (EIO); 206 } 207 /* initiate async i/o */ 208 if (read) { 209 rw_exit(&dn->dn_struct_rwlock); 210 (void) dbuf_read(db, zio, flags); 211 rw_enter(&dn->dn_struct_rwlock, RW_READER); 212 } 213 dbp[i] = &db->db; 214 } 215 rw_exit(&dn->dn_struct_rwlock); 216 217 /* wait for async i/o */ 218 err = zio_wait(zio); 219 if (err) { 220 dmu_buf_rele_array(dbp, nblks, tag); 221 return (err); 222 } 223 224 /* wait for other io to complete */ 225 if (read) { 226 for (i = 0; i < nblks; i++) { 227 dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i]; 228 mutex_enter(&db->db_mtx); 229 while (db->db_state == DB_READ || 230 db->db_state == DB_FILL) 231 cv_wait(&db->db_changed, &db->db_mtx); 232 if (db->db_state == DB_UNCACHED) 233 err = EIO; 234 mutex_exit(&db->db_mtx); 235 if (err) { 236 dmu_buf_rele_array(dbp, nblks, tag); 237 return (err); 238 } 239 } 240 } 241 242 *numbufsp = nblks; 243 *dbpp = dbp; 244 return (0); 245 } 246 247 static int 248 dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset, 249 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp) 250 { 251 dnode_t *dn; 252 int err; 253 254 err = dnode_hold(os->os, object, FTAG, &dn); 255 if (err) 256 return (err); 257 258 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag, 259 numbufsp, dbpp); 260 261 dnode_rele(dn, FTAG); 262 263 return (err); 264 } 265 266 int 267 dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset, 268 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp) 269 { 270 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode; 271 int err; 272 273 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag, 274 numbufsp, dbpp); 275 276 return (err); 277 } 278 279 void 280 dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, void *tag) 281 { 282 int i; 283 dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake; 284 285 if (numbufs == 0) 286 return; 287 288 for (i = 0; i < numbufs; i++) { 289 if (dbp[i]) 290 dbuf_rele(dbp[i], tag); 291 } 292 293 kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs); 294 } 295 296 void 297 dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len) 298 { 299 dnode_t *dn; 300 uint64_t blkid; 301 int nblks, i, err; 302 303 if (zfs_prefetch_disable) 304 return; 305 306 if (len == 0) { /* they're interested in the bonus buffer */ 307 dn = os->os->os_meta_dnode; 308 309 if (object == 0 || object >= DN_MAX_OBJECT) 310 return; 311 312 rw_enter(&dn->dn_struct_rwlock, RW_READER); 313 blkid = dbuf_whichblock(dn, object * sizeof (dnode_phys_t)); 314 dbuf_prefetch(dn, blkid); 315 rw_exit(&dn->dn_struct_rwlock); 316 return; 317 } 318 319 /* 320 * XXX - Note, if the dnode for the requested object is not 321 * already cached, we will do a *synchronous* read in the 322 * dnode_hold() call. The same is true for any indirects. 323 */ 324 err = dnode_hold(os->os, object, FTAG, &dn); 325 if (err != 0) 326 return; 327 328 rw_enter(&dn->dn_struct_rwlock, RW_READER); 329 if (dn->dn_datablkshift) { 330 int blkshift = dn->dn_datablkshift; 331 nblks = (P2ROUNDUP(offset+len, 1<<blkshift) - 332 P2ALIGN(offset, 1<<blkshift)) >> blkshift; 333 } else { 334 nblks = (offset < dn->dn_datablksz); 335 } 336 337 if (nblks != 0) { 338 blkid = dbuf_whichblock(dn, offset); 339 for (i = 0; i < nblks; i++) 340 dbuf_prefetch(dn, blkid+i); 341 } 342 343 rw_exit(&dn->dn_struct_rwlock); 344 345 dnode_rele(dn, FTAG); 346 } 347 348 int 349 dmu_free_range(objset_t *os, uint64_t object, uint64_t offset, 350 uint64_t size, dmu_tx_t *tx) 351 { 352 dnode_t *dn; 353 int err = dnode_hold(os->os, object, FTAG, &dn); 354 if (err) 355 return (err); 356 ASSERT(offset < UINT64_MAX); 357 ASSERT(size == -1ULL || size <= UINT64_MAX - offset); 358 dnode_free_range(dn, offset, size, tx); 359 dnode_rele(dn, FTAG); 360 return (0); 361 } 362 363 int 364 dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 365 void *buf) 366 { 367 dnode_t *dn; 368 dmu_buf_t **dbp; 369 int numbufs, i, err; 370 371 err = dnode_hold(os->os, object, FTAG, &dn); 372 if (err) 373 return (err); 374 375 /* 376 * Deal with odd block sizes, where there can't be data past the first 377 * block. If we ever do the tail block optimization, we will need to 378 * handle that here as well. 379 */ 380 if (dn->dn_datablkshift == 0) { 381 int newsz = offset > dn->dn_datablksz ? 0 : 382 MIN(size, dn->dn_datablksz - offset); 383 bzero((char *)buf + newsz, size - newsz); 384 size = newsz; 385 } 386 387 while (size > 0) { 388 uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2); 389 int err; 390 391 /* 392 * NB: we could do this block-at-a-time, but it's nice 393 * to be reading in parallel. 394 */ 395 err = dmu_buf_hold_array_by_dnode(dn, offset, mylen, 396 TRUE, FTAG, &numbufs, &dbp); 397 if (err) 398 return (err); 399 400 for (i = 0; i < numbufs; i++) { 401 int tocpy; 402 int bufoff; 403 dmu_buf_t *db = dbp[i]; 404 405 ASSERT(size > 0); 406 407 bufoff = offset - db->db_offset; 408 tocpy = (int)MIN(db->db_size - bufoff, size); 409 410 bcopy((char *)db->db_data + bufoff, buf, tocpy); 411 412 offset += tocpy; 413 size -= tocpy; 414 buf = (char *)buf + tocpy; 415 } 416 dmu_buf_rele_array(dbp, numbufs, FTAG); 417 } 418 dnode_rele(dn, FTAG); 419 return (0); 420 } 421 422 void 423 dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 424 const void *buf, dmu_tx_t *tx) 425 { 426 dmu_buf_t **dbp; 427 int numbufs, i; 428 429 if (size == 0) 430 return; 431 432 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size, 433 FALSE, FTAG, &numbufs, &dbp)); 434 435 for (i = 0; i < numbufs; i++) { 436 int tocpy; 437 int bufoff; 438 dmu_buf_t *db = dbp[i]; 439 440 ASSERT(size > 0); 441 442 bufoff = offset - db->db_offset; 443 tocpy = (int)MIN(db->db_size - bufoff, size); 444 445 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 446 447 if (tocpy == db->db_size) 448 dmu_buf_will_fill(db, tx); 449 else 450 dmu_buf_will_dirty(db, tx); 451 452 bcopy(buf, (char *)db->db_data + bufoff, tocpy); 453 454 if (tocpy == db->db_size) 455 dmu_buf_fill_done(db, tx); 456 457 offset += tocpy; 458 size -= tocpy; 459 buf = (char *)buf + tocpy; 460 } 461 dmu_buf_rele_array(dbp, numbufs, FTAG); 462 } 463 464 #ifdef _KERNEL 465 int 466 dmu_read_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size) 467 { 468 dmu_buf_t **dbp; 469 int numbufs, i, err; 470 471 /* 472 * NB: we could do this block-at-a-time, but it's nice 473 * to be reading in parallel. 474 */ 475 err = dmu_buf_hold_array(os, object, uio->uio_loffset, size, TRUE, FTAG, 476 &numbufs, &dbp); 477 if (err) 478 return (err); 479 480 for (i = 0; i < numbufs; i++) { 481 int tocpy; 482 int bufoff; 483 dmu_buf_t *db = dbp[i]; 484 485 ASSERT(size > 0); 486 487 bufoff = uio->uio_loffset - db->db_offset; 488 tocpy = (int)MIN(db->db_size - bufoff, size); 489 490 err = uiomove((char *)db->db_data + bufoff, tocpy, 491 UIO_READ, uio); 492 if (err) 493 break; 494 495 size -= tocpy; 496 } 497 dmu_buf_rele_array(dbp, numbufs, FTAG); 498 499 return (err); 500 } 501 502 int 503 dmu_write_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size, 504 dmu_tx_t *tx) 505 { 506 dmu_buf_t **dbp; 507 int numbufs, i; 508 int err = 0; 509 510 if (size == 0) 511 return (0); 512 513 err = dmu_buf_hold_array(os, object, uio->uio_loffset, size, 514 FALSE, FTAG, &numbufs, &dbp); 515 if (err) 516 return (err); 517 518 for (i = 0; i < numbufs; i++) { 519 int tocpy; 520 int bufoff; 521 dmu_buf_t *db = dbp[i]; 522 523 ASSERT(size > 0); 524 525 bufoff = uio->uio_loffset - db->db_offset; 526 tocpy = (int)MIN(db->db_size - bufoff, size); 527 528 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 529 530 if (tocpy == db->db_size) 531 dmu_buf_will_fill(db, tx); 532 else 533 dmu_buf_will_dirty(db, tx); 534 535 /* 536 * XXX uiomove could block forever (eg. nfs-backed 537 * pages). There needs to be a uiolockdown() function 538 * to lock the pages in memory, so that uiomove won't 539 * block. 540 */ 541 err = uiomove((char *)db->db_data + bufoff, tocpy, 542 UIO_WRITE, uio); 543 544 if (tocpy == db->db_size) 545 dmu_buf_fill_done(db, tx); 546 547 if (err) 548 break; 549 550 size -= tocpy; 551 } 552 dmu_buf_rele_array(dbp, numbufs, FTAG); 553 return (err); 554 } 555 556 int 557 dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 558 page_t *pp, dmu_tx_t *tx) 559 { 560 dmu_buf_t **dbp; 561 int numbufs, i; 562 int err; 563 564 if (size == 0) 565 return (0); 566 567 err = dmu_buf_hold_array(os, object, offset, size, 568 FALSE, FTAG, &numbufs, &dbp); 569 if (err) 570 return (err); 571 572 for (i = 0; i < numbufs; i++) { 573 int tocpy, copied, thiscpy; 574 int bufoff; 575 dmu_buf_t *db = dbp[i]; 576 caddr_t va; 577 578 ASSERT(size > 0); 579 ASSERT3U(db->db_size, >=, PAGESIZE); 580 581 bufoff = offset - db->db_offset; 582 tocpy = (int)MIN(db->db_size - bufoff, size); 583 584 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 585 586 if (tocpy == db->db_size) 587 dmu_buf_will_fill(db, tx); 588 else 589 dmu_buf_will_dirty(db, tx); 590 591 for (copied = 0; copied < tocpy; copied += PAGESIZE) { 592 ASSERT3U(pp->p_offset, ==, db->db_offset + bufoff); 593 thiscpy = MIN(PAGESIZE, tocpy - copied); 594 va = ppmapin(pp, PROT_READ, (caddr_t)-1); 595 bcopy(va, (char *)db->db_data + bufoff, thiscpy); 596 ppmapout(va); 597 pp = pp->p_next; 598 bufoff += PAGESIZE; 599 } 600 601 if (tocpy == db->db_size) 602 dmu_buf_fill_done(db, tx); 603 604 if (err) 605 break; 606 607 offset += tocpy; 608 size -= tocpy; 609 } 610 dmu_buf_rele_array(dbp, numbufs, FTAG); 611 return (err); 612 } 613 #endif 614 615 typedef struct { 616 dbuf_dirty_record_t *dr; 617 dmu_sync_cb_t *done; 618 void *arg; 619 } dmu_sync_arg_t; 620 621 /* ARGSUSED */ 622 static void 623 dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg) 624 { 625 dmu_sync_arg_t *in = varg; 626 dbuf_dirty_record_t *dr = in->dr; 627 dmu_buf_impl_t *db = dr->dr_dbuf; 628 dmu_sync_cb_t *done = in->done; 629 630 if (!BP_IS_HOLE(zio->io_bp)) { 631 zio->io_bp->blk_fill = 1; 632 BP_SET_TYPE(zio->io_bp, db->db_dnode->dn_type); 633 BP_SET_LEVEL(zio->io_bp, 0); 634 } 635 636 mutex_enter(&db->db_mtx); 637 ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC); 638 dr->dt.dl.dr_overridden_by = *zio->io_bp; /* structure assignment */ 639 dr->dt.dl.dr_override_state = DR_OVERRIDDEN; 640 cv_broadcast(&db->db_changed); 641 mutex_exit(&db->db_mtx); 642 643 if (done) 644 done(&(db->db), in->arg); 645 646 kmem_free(in, sizeof (dmu_sync_arg_t)); 647 } 648 649 /* 650 * Intent log support: sync the block associated with db to disk. 651 * N.B. and XXX: the caller is responsible for making sure that the 652 * data isn't changing while dmu_sync() is writing it. 653 * 654 * Return values: 655 * 656 * EEXIST: this txg has already been synced, so there's nothing to to. 657 * The caller should not log the write. 658 * 659 * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do. 660 * The caller should not log the write. 661 * 662 * EALREADY: this block is already in the process of being synced. 663 * The caller should track its progress (somehow). 664 * 665 * EINPROGRESS: the IO has been initiated. 666 * The caller should log this blkptr in the callback. 667 * 668 * 0: completed. Sets *bp to the blkptr just written. 669 * The caller should log this blkptr immediately. 670 */ 671 int 672 dmu_sync(zio_t *pio, dmu_buf_t *db_fake, 673 blkptr_t *bp, uint64_t txg, dmu_sync_cb_t *done, void *arg) 674 { 675 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 676 objset_impl_t *os = db->db_objset; 677 dsl_pool_t *dp = os->os_dsl_dataset->ds_dir->dd_pool; 678 tx_state_t *tx = &dp->dp_tx; 679 dbuf_dirty_record_t *dr; 680 dmu_sync_arg_t *in; 681 zbookmark_t zb; 682 zio_t *zio; 683 int zio_flags; 684 int err; 685 686 ASSERT(BP_IS_HOLE(bp)); 687 ASSERT(txg != 0); 688 689 690 dprintf("dmu_sync txg=%llu, s,o,q %llu %llu %llu\n", 691 txg, tx->tx_synced_txg, tx->tx_open_txg, tx->tx_quiesced_txg); 692 693 /* 694 * XXX - would be nice if we could do this without suspending... 695 */ 696 txg_suspend(dp); 697 698 /* 699 * If this txg already synced, there's nothing to do. 700 */ 701 if (txg <= tx->tx_synced_txg) { 702 txg_resume(dp); 703 /* 704 * If we're running ziltest, we need the blkptr regardless. 705 */ 706 if (txg > spa_freeze_txg(dp->dp_spa)) { 707 /* if db_blkptr == NULL, this was an empty write */ 708 if (db->db_blkptr) 709 *bp = *db->db_blkptr; /* structure assignment */ 710 return (0); 711 } 712 return (EEXIST); 713 } 714 715 mutex_enter(&db->db_mtx); 716 717 if (txg == tx->tx_syncing_txg) { 718 while (db->db_data_pending) { 719 /* 720 * IO is in-progress. Wait for it to finish. 721 * XXX - would be nice to be able to somehow "attach" 722 * this zio to the parent zio passed in. 723 */ 724 cv_wait(&db->db_changed, &db->db_mtx); 725 if (!db->db_data_pending && 726 db->db_blkptr && BP_IS_HOLE(db->db_blkptr)) { 727 /* 728 * IO was compressed away 729 */ 730 *bp = *db->db_blkptr; /* structure assignment */ 731 mutex_exit(&db->db_mtx); 732 txg_resume(dp); 733 return (0); 734 } 735 ASSERT(db->db_data_pending || 736 (db->db_blkptr && db->db_blkptr->blk_birth == txg)); 737 } 738 739 if (db->db_blkptr && db->db_blkptr->blk_birth == txg) { 740 /* 741 * IO is already completed. 742 */ 743 *bp = *db->db_blkptr; /* structure assignment */ 744 mutex_exit(&db->db_mtx); 745 txg_resume(dp); 746 return (0); 747 } 748 } 749 750 dr = db->db_last_dirty; 751 while (dr && dr->dr_txg > txg) 752 dr = dr->dr_next; 753 if (dr == NULL || dr->dr_txg < txg) { 754 /* 755 * This dbuf isn't dirty, must have been free_range'd. 756 * There's no need to log writes to freed blocks, so we're done. 757 */ 758 mutex_exit(&db->db_mtx); 759 txg_resume(dp); 760 return (ENOENT); 761 } 762 763 ASSERT(dr->dr_txg == txg); 764 if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC) { 765 /* 766 * We have already issued a sync write for this buffer. 767 */ 768 mutex_exit(&db->db_mtx); 769 txg_resume(dp); 770 return (EALREADY); 771 } else if (dr->dt.dl.dr_override_state == DR_OVERRIDDEN) { 772 /* 773 * This buffer has already been synced. It could not 774 * have been dirtied since, or we would have cleared the state. 775 */ 776 *bp = dr->dt.dl.dr_overridden_by; /* structure assignment */ 777 mutex_exit(&db->db_mtx); 778 txg_resume(dp); 779 return (0); 780 } 781 782 dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC; 783 in = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP); 784 in->dr = dr; 785 in->done = done; 786 in->arg = arg; 787 mutex_exit(&db->db_mtx); 788 txg_resume(dp); 789 790 zb.zb_objset = os->os_dsl_dataset->ds_object; 791 zb.zb_object = db->db.db_object; 792 zb.zb_level = db->db_level; 793 zb.zb_blkid = db->db_blkid; 794 zio_flags = ZIO_FLAG_MUSTSUCCEED; 795 if (dmu_ot[db->db_dnode->dn_type].ot_metadata || zb.zb_level != 0) 796 zio_flags |= ZIO_FLAG_METADATA; 797 zio = arc_write(pio, os->os_spa, 798 zio_checksum_select(db->db_dnode->dn_checksum, os->os_checksum), 799 zio_compress_select(db->db_dnode->dn_compress, os->os_compress), 800 dmu_get_replication_level(os->os_spa, &zb, db->db_dnode->dn_type), 801 txg, bp, dr->dt.dl.dr_data, NULL, dmu_sync_done, in, 802 ZIO_PRIORITY_SYNC_WRITE, zio_flags, &zb); 803 804 if (pio) { 805 zio_nowait(zio); 806 err = EINPROGRESS; 807 } else { 808 err = zio_wait(zio); 809 ASSERT(err == 0); 810 } 811 return (err); 812 } 813 814 int 815 dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs, 816 dmu_tx_t *tx) 817 { 818 dnode_t *dn; 819 int err; 820 821 err = dnode_hold(os->os, object, FTAG, &dn); 822 if (err) 823 return (err); 824 err = dnode_set_blksz(dn, size, ibs, tx); 825 dnode_rele(dn, FTAG); 826 return (err); 827 } 828 829 void 830 dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum, 831 dmu_tx_t *tx) 832 { 833 dnode_t *dn; 834 835 /* XXX assumes dnode_hold will not get an i/o error */ 836 (void) dnode_hold(os->os, object, FTAG, &dn); 837 ASSERT(checksum < ZIO_CHECKSUM_FUNCTIONS); 838 dn->dn_checksum = checksum; 839 dnode_setdirty(dn, tx); 840 dnode_rele(dn, FTAG); 841 } 842 843 void 844 dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress, 845 dmu_tx_t *tx) 846 { 847 dnode_t *dn; 848 849 /* XXX assumes dnode_hold will not get an i/o error */ 850 (void) dnode_hold(os->os, object, FTAG, &dn); 851 ASSERT(compress < ZIO_COMPRESS_FUNCTIONS); 852 dn->dn_compress = compress; 853 dnode_setdirty(dn, tx); 854 dnode_rele(dn, FTAG); 855 } 856 857 /* 858 * XXX - eventually, this should take into account per-dataset (or 859 * even per-object?) user requests for higher levels of replication. 860 */ 861 int 862 dmu_get_replication_level(spa_t *spa, zbookmark_t *zb, dmu_object_type_t ot) 863 { 864 int ncopies = 1; 865 866 if (dmu_ot[ot].ot_metadata) 867 ncopies++; 868 if (zb->zb_level != 0) 869 ncopies++; 870 if (zb->zb_objset == 0 && zb->zb_object == 0) 871 ncopies++; 872 return (MIN(ncopies, spa_max_replication(spa))); 873 } 874 875 int 876 dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off) 877 { 878 dnode_t *dn; 879 int i, err; 880 881 err = dnode_hold(os->os, object, FTAG, &dn); 882 if (err) 883 return (err); 884 /* 885 * Sync any current changes before 886 * we go trundling through the block pointers. 887 */ 888 for (i = 0; i < TXG_SIZE; i++) { 889 if (list_link_active(&dn->dn_dirty_link[i])) 890 break; 891 } 892 if (i != TXG_SIZE) { 893 dnode_rele(dn, FTAG); 894 txg_wait_synced(dmu_objset_pool(os), 0); 895 err = dnode_hold(os->os, object, FTAG, &dn); 896 if (err) 897 return (err); 898 } 899 900 err = dnode_next_offset(dn, hole, off, 1, 1, 0); 901 dnode_rele(dn, FTAG); 902 903 return (err); 904 } 905 906 void 907 dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi) 908 { 909 rw_enter(&dn->dn_struct_rwlock, RW_READER); 910 mutex_enter(&dn->dn_mtx); 911 912 doi->doi_data_block_size = dn->dn_datablksz; 913 doi->doi_metadata_block_size = dn->dn_indblkshift ? 914 1ULL << dn->dn_indblkshift : 0; 915 doi->doi_indirection = dn->dn_nlevels; 916 doi->doi_checksum = dn->dn_checksum; 917 doi->doi_compress = dn->dn_compress; 918 doi->doi_physical_blks = (DN_USED_BYTES(dn->dn_phys) + 919 SPA_MINBLOCKSIZE/2) >> SPA_MINBLOCKSHIFT; 920 doi->doi_max_block_offset = dn->dn_phys->dn_maxblkid; 921 doi->doi_type = dn->dn_type; 922 doi->doi_bonus_size = dn->dn_bonuslen; 923 doi->doi_bonus_type = dn->dn_bonustype; 924 925 mutex_exit(&dn->dn_mtx); 926 rw_exit(&dn->dn_struct_rwlock); 927 } 928 929 /* 930 * Get information on a DMU object. 931 * If doi is NULL, just indicates whether the object exists. 932 */ 933 int 934 dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi) 935 { 936 dnode_t *dn; 937 int err = dnode_hold(os->os, object, FTAG, &dn); 938 939 if (err) 940 return (err); 941 942 if (doi != NULL) 943 dmu_object_info_from_dnode(dn, doi); 944 945 dnode_rele(dn, FTAG); 946 return (0); 947 } 948 949 /* 950 * As above, but faster; can be used when you have a held dbuf in hand. 951 */ 952 void 953 dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi) 954 { 955 dmu_object_info_from_dnode(((dmu_buf_impl_t *)db)->db_dnode, doi); 956 } 957 958 /* 959 * Faster still when you only care about the size. 960 * This is specifically optimized for zfs_getattr(). 961 */ 962 void 963 dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize, u_longlong_t *nblk512) 964 { 965 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode; 966 967 *blksize = dn->dn_datablksz; 968 /* add 1 for dnode space */ 969 *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >> 970 SPA_MINBLOCKSHIFT) + 1; 971 } 972 973 void 974 byteswap_uint64_array(void *vbuf, size_t size) 975 { 976 uint64_t *buf = vbuf; 977 size_t count = size >> 3; 978 int i; 979 980 ASSERT((size & 7) == 0); 981 982 for (i = 0; i < count; i++) 983 buf[i] = BSWAP_64(buf[i]); 984 } 985 986 void 987 byteswap_uint32_array(void *vbuf, size_t size) 988 { 989 uint32_t *buf = vbuf; 990 size_t count = size >> 2; 991 int i; 992 993 ASSERT((size & 3) == 0); 994 995 for (i = 0; i < count; i++) 996 buf[i] = BSWAP_32(buf[i]); 997 } 998 999 void 1000 byteswap_uint16_array(void *vbuf, size_t size) 1001 { 1002 uint16_t *buf = vbuf; 1003 size_t count = size >> 1; 1004 int i; 1005 1006 ASSERT((size & 1) == 0); 1007 1008 for (i = 0; i < count; i++) 1009 buf[i] = BSWAP_16(buf[i]); 1010 } 1011 1012 /* ARGSUSED */ 1013 void 1014 byteswap_uint8_array(void *vbuf, size_t size) 1015 { 1016 } 1017 1018 void 1019 dmu_init(void) 1020 { 1021 dbuf_init(); 1022 dnode_init(); 1023 arc_init(); 1024 } 1025 1026 void 1027 dmu_fini(void) 1028 { 1029 arc_fini(); 1030 dnode_fini(); 1031 dbuf_fini(); 1032 } 1033