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/dmu.h> 27 #include <sys/dmu_impl.h> 28 #include <sys/dmu_tx.h> 29 #include <sys/dbuf.h> 30 #include <sys/dnode.h> 31 #include <sys/zfs_context.h> 32 #include <sys/dmu_objset.h> 33 #include <sys/dmu_traverse.h> 34 #include <sys/dsl_dataset.h> 35 #include <sys/dsl_dir.h> 36 #include <sys/dsl_pool.h> 37 #include <sys/dsl_synctask.h> 38 #include <sys/dsl_prop.h> 39 #include <sys/dmu_zfetch.h> 40 #include <sys/zfs_ioctl.h> 41 #include <sys/zap.h> 42 #include <sys/zio_checksum.h> 43 #ifdef _KERNEL 44 #include <sys/vmsystm.h> 45 #include <sys/zfs_znode.h> 46 #endif 47 48 const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES] = { 49 { byteswap_uint8_array, TRUE, "unallocated" }, 50 { zap_byteswap, TRUE, "object directory" }, 51 { byteswap_uint64_array, TRUE, "object array" }, 52 { byteswap_uint8_array, TRUE, "packed nvlist" }, 53 { byteswap_uint64_array, TRUE, "packed nvlist size" }, 54 { byteswap_uint64_array, TRUE, "bplist" }, 55 { byteswap_uint64_array, TRUE, "bplist header" }, 56 { byteswap_uint64_array, TRUE, "SPA space map header" }, 57 { byteswap_uint64_array, TRUE, "SPA space map" }, 58 { byteswap_uint64_array, TRUE, "ZIL intent log" }, 59 { dnode_buf_byteswap, TRUE, "DMU dnode" }, 60 { dmu_objset_byteswap, TRUE, "DMU objset" }, 61 { byteswap_uint64_array, TRUE, "DSL directory" }, 62 { zap_byteswap, TRUE, "DSL directory child map"}, 63 { zap_byteswap, TRUE, "DSL dataset snap map" }, 64 { zap_byteswap, TRUE, "DSL props" }, 65 { byteswap_uint64_array, TRUE, "DSL dataset" }, 66 { zfs_znode_byteswap, TRUE, "ZFS znode" }, 67 { zfs_oldacl_byteswap, TRUE, "ZFS V0 ACL" }, 68 { byteswap_uint8_array, FALSE, "ZFS plain file" }, 69 { zap_byteswap, TRUE, "ZFS directory" }, 70 { zap_byteswap, TRUE, "ZFS master node" }, 71 { zap_byteswap, TRUE, "ZFS delete queue" }, 72 { byteswap_uint8_array, FALSE, "zvol object" }, 73 { zap_byteswap, TRUE, "zvol prop" }, 74 { byteswap_uint8_array, FALSE, "other uint8[]" }, 75 { byteswap_uint64_array, FALSE, "other uint64[]" }, 76 { zap_byteswap, TRUE, "other ZAP" }, 77 { zap_byteswap, TRUE, "persistent error log" }, 78 { byteswap_uint8_array, TRUE, "SPA history" }, 79 { byteswap_uint64_array, TRUE, "SPA history offsets" }, 80 { zap_byteswap, TRUE, "Pool properties" }, 81 { zap_byteswap, TRUE, "DSL permissions" }, 82 { zfs_acl_byteswap, TRUE, "ZFS ACL" }, 83 { byteswap_uint8_array, TRUE, "ZFS SYSACL" }, 84 { byteswap_uint8_array, TRUE, "FUID table" }, 85 { byteswap_uint64_array, TRUE, "FUID table size" }, 86 { zap_byteswap, TRUE, "DSL dataset next clones"}, 87 { zap_byteswap, TRUE, "scrub work queue" }, 88 { zap_byteswap, TRUE, "ZFS user/group used" }, 89 { zap_byteswap, TRUE, "ZFS user/group quota" }, 90 }; 91 92 int 93 dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset, 94 void *tag, dmu_buf_t **dbp) 95 { 96 dnode_t *dn; 97 uint64_t blkid; 98 dmu_buf_impl_t *db; 99 int err; 100 101 err = dnode_hold(os->os, object, FTAG, &dn); 102 if (err) 103 return (err); 104 blkid = dbuf_whichblock(dn, offset); 105 rw_enter(&dn->dn_struct_rwlock, RW_READER); 106 db = dbuf_hold(dn, blkid, tag); 107 rw_exit(&dn->dn_struct_rwlock); 108 if (db == NULL) { 109 err = EIO; 110 } else { 111 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 112 if (err) { 113 dbuf_rele(db, tag); 114 db = NULL; 115 } 116 } 117 118 dnode_rele(dn, FTAG); 119 *dbp = &db->db; 120 return (err); 121 } 122 123 int 124 dmu_bonus_max(void) 125 { 126 return (DN_MAX_BONUSLEN); 127 } 128 129 int 130 dmu_set_bonus(dmu_buf_t *db, int newsize, dmu_tx_t *tx) 131 { 132 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode; 133 134 if (dn->dn_bonus != (dmu_buf_impl_t *)db) 135 return (EINVAL); 136 if (newsize < 0 || newsize > db->db_size) 137 return (EINVAL); 138 dnode_setbonuslen(dn, newsize, tx); 139 return (0); 140 } 141 142 /* 143 * returns ENOENT, EIO, or 0. 144 */ 145 int 146 dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **dbp) 147 { 148 dnode_t *dn; 149 dmu_buf_impl_t *db; 150 int error; 151 152 error = dnode_hold(os->os, object, FTAG, &dn); 153 if (error) 154 return (error); 155 156 rw_enter(&dn->dn_struct_rwlock, RW_READER); 157 if (dn->dn_bonus == NULL) { 158 rw_exit(&dn->dn_struct_rwlock); 159 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 160 if (dn->dn_bonus == NULL) 161 dbuf_create_bonus(dn); 162 } 163 db = dn->dn_bonus; 164 rw_exit(&dn->dn_struct_rwlock); 165 166 /* as long as the bonus buf is held, the dnode will be held */ 167 if (refcount_add(&db->db_holds, tag) == 1) 168 VERIFY(dnode_add_ref(dn, db)); 169 170 dnode_rele(dn, FTAG); 171 172 VERIFY(0 == dbuf_read(db, NULL, DB_RF_MUST_SUCCEED)); 173 174 *dbp = &db->db; 175 return (0); 176 } 177 178 /* 179 * Note: longer-term, we should modify all of the dmu_buf_*() interfaces 180 * to take a held dnode rather than <os, object> -- the lookup is wasteful, 181 * and can induce severe lock contention when writing to several files 182 * whose dnodes are in the same block. 183 */ 184 static int 185 dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, 186 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp) 187 { 188 dsl_pool_t *dp = NULL; 189 dmu_buf_t **dbp; 190 uint64_t blkid, nblks, i; 191 uint32_t flags; 192 int err; 193 zio_t *zio; 194 hrtime_t start; 195 196 ASSERT(length <= DMU_MAX_ACCESS); 197 198 flags = DB_RF_CANFAIL | DB_RF_NEVERWAIT; 199 if (length > zfetch_array_rd_sz) 200 flags |= DB_RF_NOPREFETCH; 201 202 rw_enter(&dn->dn_struct_rwlock, RW_READER); 203 if (dn->dn_datablkshift) { 204 int blkshift = dn->dn_datablkshift; 205 nblks = (P2ROUNDUP(offset+length, 1ULL<<blkshift) - 206 P2ALIGN(offset, 1ULL<<blkshift)) >> blkshift; 207 } else { 208 if (offset + length > dn->dn_datablksz) { 209 zfs_panic_recover("zfs: accessing past end of object " 210 "%llx/%llx (size=%u access=%llu+%llu)", 211 (longlong_t)dn->dn_objset-> 212 os_dsl_dataset->ds_object, 213 (longlong_t)dn->dn_object, dn->dn_datablksz, 214 (longlong_t)offset, (longlong_t)length); 215 return (EIO); 216 } 217 nblks = 1; 218 } 219 dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_SLEEP); 220 221 if (dn->dn_objset->os_dsl_dataset) 222 dp = dn->dn_objset->os_dsl_dataset->ds_dir->dd_pool; 223 if (dp && dsl_pool_sync_context(dp)) 224 start = gethrtime(); 225 zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, ZIO_FLAG_CANFAIL); 226 blkid = dbuf_whichblock(dn, offset); 227 for (i = 0; i < nblks; i++) { 228 dmu_buf_impl_t *db = dbuf_hold(dn, blkid+i, tag); 229 if (db == NULL) { 230 rw_exit(&dn->dn_struct_rwlock); 231 dmu_buf_rele_array(dbp, nblks, tag); 232 zio_nowait(zio); 233 return (EIO); 234 } 235 /* initiate async i/o */ 236 if (read) { 237 rw_exit(&dn->dn_struct_rwlock); 238 (void) dbuf_read(db, zio, flags); 239 rw_enter(&dn->dn_struct_rwlock, RW_READER); 240 } 241 dbp[i] = &db->db; 242 } 243 rw_exit(&dn->dn_struct_rwlock); 244 245 /* wait for async i/o */ 246 err = zio_wait(zio); 247 /* track read overhead when we are in sync context */ 248 if (dp && dsl_pool_sync_context(dp)) 249 dp->dp_read_overhead += gethrtime() - start; 250 if (err) { 251 dmu_buf_rele_array(dbp, nblks, tag); 252 return (err); 253 } 254 255 /* wait for other io to complete */ 256 if (read) { 257 for (i = 0; i < nblks; i++) { 258 dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i]; 259 mutex_enter(&db->db_mtx); 260 while (db->db_state == DB_READ || 261 db->db_state == DB_FILL) 262 cv_wait(&db->db_changed, &db->db_mtx); 263 if (db->db_state == DB_UNCACHED) 264 err = EIO; 265 mutex_exit(&db->db_mtx); 266 if (err) { 267 dmu_buf_rele_array(dbp, nblks, tag); 268 return (err); 269 } 270 } 271 } 272 273 *numbufsp = nblks; 274 *dbpp = dbp; 275 return (0); 276 } 277 278 static int 279 dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset, 280 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp) 281 { 282 dnode_t *dn; 283 int err; 284 285 err = dnode_hold(os->os, object, FTAG, &dn); 286 if (err) 287 return (err); 288 289 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag, 290 numbufsp, dbpp); 291 292 dnode_rele(dn, FTAG); 293 294 return (err); 295 } 296 297 int 298 dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset, 299 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp) 300 { 301 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode; 302 int err; 303 304 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag, 305 numbufsp, dbpp); 306 307 return (err); 308 } 309 310 void 311 dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, void *tag) 312 { 313 int i; 314 dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake; 315 316 if (numbufs == 0) 317 return; 318 319 for (i = 0; i < numbufs; i++) { 320 if (dbp[i]) 321 dbuf_rele(dbp[i], tag); 322 } 323 324 kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs); 325 } 326 327 void 328 dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len) 329 { 330 dnode_t *dn; 331 uint64_t blkid; 332 int nblks, i, err; 333 334 if (zfs_prefetch_disable) 335 return; 336 337 if (len == 0) { /* they're interested in the bonus buffer */ 338 dn = os->os->os_meta_dnode; 339 340 if (object == 0 || object >= DN_MAX_OBJECT) 341 return; 342 343 rw_enter(&dn->dn_struct_rwlock, RW_READER); 344 blkid = dbuf_whichblock(dn, object * sizeof (dnode_phys_t)); 345 dbuf_prefetch(dn, blkid); 346 rw_exit(&dn->dn_struct_rwlock); 347 return; 348 } 349 350 /* 351 * XXX - Note, if the dnode for the requested object is not 352 * already cached, we will do a *synchronous* read in the 353 * dnode_hold() call. The same is true for any indirects. 354 */ 355 err = dnode_hold(os->os, object, FTAG, &dn); 356 if (err != 0) 357 return; 358 359 rw_enter(&dn->dn_struct_rwlock, RW_READER); 360 if (dn->dn_datablkshift) { 361 int blkshift = dn->dn_datablkshift; 362 nblks = (P2ROUNDUP(offset+len, 1<<blkshift) - 363 P2ALIGN(offset, 1<<blkshift)) >> blkshift; 364 } else { 365 nblks = (offset < dn->dn_datablksz); 366 } 367 368 if (nblks != 0) { 369 blkid = dbuf_whichblock(dn, offset); 370 for (i = 0; i < nblks; i++) 371 dbuf_prefetch(dn, blkid+i); 372 } 373 374 rw_exit(&dn->dn_struct_rwlock); 375 376 dnode_rele(dn, FTAG); 377 } 378 379 static int 380 get_next_chunk(dnode_t *dn, uint64_t *offset, uint64_t limit) 381 { 382 uint64_t len = *offset - limit; 383 uint64_t chunk_len = dn->dn_datablksz * DMU_MAX_DELETEBLKCNT; 384 uint64_t subchunk = 385 dn->dn_datablksz * EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT); 386 387 ASSERT(limit <= *offset); 388 389 if (len <= chunk_len) { 390 *offset = limit; 391 return (0); 392 } 393 394 ASSERT(ISP2(subchunk)); 395 396 while (*offset > limit) { 397 uint64_t initial_offset = P2ROUNDUP(*offset, subchunk); 398 uint64_t delta; 399 int err; 400 401 /* skip over allocated data */ 402 err = dnode_next_offset(dn, 403 DNODE_FIND_HOLE|DNODE_FIND_BACKWARDS, offset, 1, 1, 0); 404 if (err == ESRCH) 405 *offset = limit; 406 else if (err) 407 return (err); 408 409 ASSERT3U(*offset, <=, initial_offset); 410 *offset = P2ALIGN(*offset, subchunk); 411 delta = initial_offset - *offset; 412 if (delta >= chunk_len) { 413 *offset += delta - chunk_len; 414 return (0); 415 } 416 chunk_len -= delta; 417 418 /* skip over unallocated data */ 419 err = dnode_next_offset(dn, 420 DNODE_FIND_BACKWARDS, offset, 1, 1, 0); 421 if (err == ESRCH) 422 *offset = limit; 423 else if (err) 424 return (err); 425 426 if (*offset < limit) 427 *offset = limit; 428 ASSERT3U(*offset, <, initial_offset); 429 } 430 return (0); 431 } 432 433 static int 434 dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset, 435 uint64_t length, boolean_t free_dnode) 436 { 437 dmu_tx_t *tx; 438 uint64_t object_size, start, end, len; 439 boolean_t trunc = (length == DMU_OBJECT_END); 440 int align, err; 441 442 align = 1 << dn->dn_datablkshift; 443 ASSERT(align > 0); 444 object_size = align == 1 ? dn->dn_datablksz : 445 (dn->dn_maxblkid + 1) << dn->dn_datablkshift; 446 447 end = offset + length; 448 if (trunc || end > object_size) 449 end = object_size; 450 if (end <= offset) 451 return (0); 452 length = end - offset; 453 454 while (length) { 455 start = end; 456 /* assert(offset <= start) */ 457 err = get_next_chunk(dn, &start, offset); 458 if (err) 459 return (err); 460 len = trunc ? DMU_OBJECT_END : end - start; 461 462 tx = dmu_tx_create(os); 463 dmu_tx_hold_free(tx, dn->dn_object, start, len); 464 err = dmu_tx_assign(tx, TXG_WAIT); 465 if (err) { 466 dmu_tx_abort(tx); 467 return (err); 468 } 469 470 dnode_free_range(dn, start, trunc ? -1 : len, tx); 471 472 if (start == 0 && free_dnode) { 473 ASSERT(trunc); 474 dnode_free(dn, tx); 475 } 476 477 length -= end - start; 478 479 dmu_tx_commit(tx); 480 end = start; 481 } 482 return (0); 483 } 484 485 int 486 dmu_free_long_range(objset_t *os, uint64_t object, 487 uint64_t offset, uint64_t length) 488 { 489 dnode_t *dn; 490 int err; 491 492 err = dnode_hold(os->os, object, FTAG, &dn); 493 if (err != 0) 494 return (err); 495 err = dmu_free_long_range_impl(os, dn, offset, length, FALSE); 496 dnode_rele(dn, FTAG); 497 return (err); 498 } 499 500 int 501 dmu_free_object(objset_t *os, uint64_t object) 502 { 503 dnode_t *dn; 504 dmu_tx_t *tx; 505 int err; 506 507 err = dnode_hold_impl(os->os, object, DNODE_MUST_BE_ALLOCATED, 508 FTAG, &dn); 509 if (err != 0) 510 return (err); 511 if (dn->dn_nlevels == 1) { 512 tx = dmu_tx_create(os); 513 dmu_tx_hold_bonus(tx, object); 514 dmu_tx_hold_free(tx, dn->dn_object, 0, DMU_OBJECT_END); 515 err = dmu_tx_assign(tx, TXG_WAIT); 516 if (err == 0) { 517 dnode_free_range(dn, 0, DMU_OBJECT_END, tx); 518 dnode_free(dn, tx); 519 dmu_tx_commit(tx); 520 } else { 521 dmu_tx_abort(tx); 522 } 523 } else { 524 err = dmu_free_long_range_impl(os, dn, 0, DMU_OBJECT_END, TRUE); 525 } 526 dnode_rele(dn, FTAG); 527 return (err); 528 } 529 530 int 531 dmu_free_range(objset_t *os, uint64_t object, uint64_t offset, 532 uint64_t size, dmu_tx_t *tx) 533 { 534 dnode_t *dn; 535 int err = dnode_hold(os->os, object, FTAG, &dn); 536 if (err) 537 return (err); 538 ASSERT(offset < UINT64_MAX); 539 ASSERT(size == -1ULL || size <= UINT64_MAX - offset); 540 dnode_free_range(dn, offset, size, tx); 541 dnode_rele(dn, FTAG); 542 return (0); 543 } 544 545 int 546 dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 547 void *buf) 548 { 549 dnode_t *dn; 550 dmu_buf_t **dbp; 551 int numbufs, i, err; 552 553 err = dnode_hold(os->os, object, FTAG, &dn); 554 if (err) 555 return (err); 556 557 /* 558 * Deal with odd block sizes, where there can't be data past the first 559 * block. If we ever do the tail block optimization, we will need to 560 * handle that here as well. 561 */ 562 if (dn->dn_datablkshift == 0) { 563 int newsz = offset > dn->dn_datablksz ? 0 : 564 MIN(size, dn->dn_datablksz - offset); 565 bzero((char *)buf + newsz, size - newsz); 566 size = newsz; 567 } 568 569 while (size > 0) { 570 uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2); 571 572 /* 573 * NB: we could do this block-at-a-time, but it's nice 574 * to be reading in parallel. 575 */ 576 err = dmu_buf_hold_array_by_dnode(dn, offset, mylen, 577 TRUE, FTAG, &numbufs, &dbp); 578 if (err) 579 break; 580 581 for (i = 0; i < numbufs; i++) { 582 int tocpy; 583 int bufoff; 584 dmu_buf_t *db = dbp[i]; 585 586 ASSERT(size > 0); 587 588 bufoff = offset - db->db_offset; 589 tocpy = (int)MIN(db->db_size - bufoff, size); 590 591 bcopy((char *)db->db_data + bufoff, buf, tocpy); 592 593 offset += tocpy; 594 size -= tocpy; 595 buf = (char *)buf + tocpy; 596 } 597 dmu_buf_rele_array(dbp, numbufs, FTAG); 598 } 599 dnode_rele(dn, FTAG); 600 return (err); 601 } 602 603 void 604 dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 605 const void *buf, dmu_tx_t *tx) 606 { 607 dmu_buf_t **dbp; 608 int numbufs, i; 609 610 if (size == 0) 611 return; 612 613 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size, 614 FALSE, FTAG, &numbufs, &dbp)); 615 616 for (i = 0; i < numbufs; i++) { 617 int tocpy; 618 int bufoff; 619 dmu_buf_t *db = dbp[i]; 620 621 ASSERT(size > 0); 622 623 bufoff = offset - db->db_offset; 624 tocpy = (int)MIN(db->db_size - bufoff, size); 625 626 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 627 628 if (tocpy == db->db_size) 629 dmu_buf_will_fill(db, tx); 630 else 631 dmu_buf_will_dirty(db, tx); 632 633 bcopy(buf, (char *)db->db_data + bufoff, tocpy); 634 635 if (tocpy == db->db_size) 636 dmu_buf_fill_done(db, tx); 637 638 offset += tocpy; 639 size -= tocpy; 640 buf = (char *)buf + tocpy; 641 } 642 dmu_buf_rele_array(dbp, numbufs, FTAG); 643 } 644 645 void 646 dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 647 dmu_tx_t *tx) 648 { 649 dmu_buf_t **dbp; 650 int numbufs, i; 651 652 if (size == 0) 653 return; 654 655 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size, 656 FALSE, FTAG, &numbufs, &dbp)); 657 658 for (i = 0; i < numbufs; i++) { 659 dmu_buf_t *db = dbp[i]; 660 661 dmu_buf_will_not_fill(db, tx); 662 } 663 dmu_buf_rele_array(dbp, numbufs, FTAG); 664 } 665 666 #ifdef _KERNEL 667 int 668 dmu_read_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size) 669 { 670 dmu_buf_t **dbp; 671 int numbufs, i, err; 672 673 /* 674 * NB: we could do this block-at-a-time, but it's nice 675 * to be reading in parallel. 676 */ 677 err = dmu_buf_hold_array(os, object, uio->uio_loffset, size, TRUE, FTAG, 678 &numbufs, &dbp); 679 if (err) 680 return (err); 681 682 for (i = 0; i < numbufs; i++) { 683 int tocpy; 684 int bufoff; 685 dmu_buf_t *db = dbp[i]; 686 687 ASSERT(size > 0); 688 689 bufoff = uio->uio_loffset - db->db_offset; 690 tocpy = (int)MIN(db->db_size - bufoff, size); 691 692 err = uiomove((char *)db->db_data + bufoff, tocpy, 693 UIO_READ, uio); 694 if (err) 695 break; 696 697 size -= tocpy; 698 } 699 dmu_buf_rele_array(dbp, numbufs, FTAG); 700 701 return (err); 702 } 703 704 int 705 dmu_write_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size, 706 dmu_tx_t *tx) 707 { 708 dmu_buf_t **dbp; 709 int numbufs, i; 710 int err = 0; 711 712 if (size == 0) 713 return (0); 714 715 err = dmu_buf_hold_array(os, object, uio->uio_loffset, size, 716 FALSE, FTAG, &numbufs, &dbp); 717 if (err) 718 return (err); 719 720 for (i = 0; i < numbufs; i++) { 721 int tocpy; 722 int bufoff; 723 dmu_buf_t *db = dbp[i]; 724 725 ASSERT(size > 0); 726 727 bufoff = uio->uio_loffset - db->db_offset; 728 tocpy = (int)MIN(db->db_size - bufoff, size); 729 730 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 731 732 if (tocpy == db->db_size) 733 dmu_buf_will_fill(db, tx); 734 else 735 dmu_buf_will_dirty(db, tx); 736 737 /* 738 * XXX uiomove could block forever (eg. nfs-backed 739 * pages). There needs to be a uiolockdown() function 740 * to lock the pages in memory, so that uiomove won't 741 * block. 742 */ 743 err = uiomove((char *)db->db_data + bufoff, tocpy, 744 UIO_WRITE, uio); 745 746 if (tocpy == db->db_size) 747 dmu_buf_fill_done(db, tx); 748 749 if (err) 750 break; 751 752 size -= tocpy; 753 } 754 dmu_buf_rele_array(dbp, numbufs, FTAG); 755 return (err); 756 } 757 758 int 759 dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 760 page_t *pp, dmu_tx_t *tx) 761 { 762 dmu_buf_t **dbp; 763 int numbufs, i; 764 int err; 765 766 if (size == 0) 767 return (0); 768 769 err = dmu_buf_hold_array(os, object, offset, size, 770 FALSE, FTAG, &numbufs, &dbp); 771 if (err) 772 return (err); 773 774 for (i = 0; i < numbufs; i++) { 775 int tocpy, copied, thiscpy; 776 int bufoff; 777 dmu_buf_t *db = dbp[i]; 778 caddr_t va; 779 780 ASSERT(size > 0); 781 ASSERT3U(db->db_size, >=, PAGESIZE); 782 783 bufoff = offset - db->db_offset; 784 tocpy = (int)MIN(db->db_size - bufoff, size); 785 786 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 787 788 if (tocpy == db->db_size) 789 dmu_buf_will_fill(db, tx); 790 else 791 dmu_buf_will_dirty(db, tx); 792 793 for (copied = 0; copied < tocpy; copied += PAGESIZE) { 794 ASSERT3U(pp->p_offset, ==, db->db_offset + bufoff); 795 thiscpy = MIN(PAGESIZE, tocpy - copied); 796 va = zfs_map_page(pp, S_READ); 797 bcopy(va, (char *)db->db_data + bufoff, thiscpy); 798 zfs_unmap_page(pp, va); 799 pp = pp->p_next; 800 bufoff += PAGESIZE; 801 } 802 803 if (tocpy == db->db_size) 804 dmu_buf_fill_done(db, tx); 805 806 if (err) 807 break; 808 809 offset += tocpy; 810 size -= tocpy; 811 } 812 dmu_buf_rele_array(dbp, numbufs, FTAG); 813 return (err); 814 } 815 #endif 816 817 /* 818 * Allocate a loaned anonymous arc buffer. 819 */ 820 arc_buf_t * 821 dmu_request_arcbuf(dmu_buf_t *handle, int size) 822 { 823 dnode_t *dn = ((dmu_buf_impl_t *)handle)->db_dnode; 824 825 return (arc_loan_buf(dn->dn_objset->os_spa, size)); 826 } 827 828 /* 829 * Free a loaned arc buffer. 830 */ 831 void 832 dmu_return_arcbuf(arc_buf_t *buf) 833 { 834 arc_return_buf(buf, FTAG); 835 VERIFY(arc_buf_remove_ref(buf, FTAG) == 1); 836 } 837 838 /* 839 * When possible directly assign passed loaned arc buffer to a dbuf. 840 * If this is not possible copy the contents of passed arc buf via 841 * dmu_write(). 842 */ 843 void 844 dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, arc_buf_t *buf, 845 dmu_tx_t *tx) 846 { 847 dnode_t *dn = ((dmu_buf_impl_t *)handle)->db_dnode; 848 dmu_buf_impl_t *db; 849 uint32_t blksz = (uint32_t)arc_buf_size(buf); 850 uint64_t blkid; 851 852 rw_enter(&dn->dn_struct_rwlock, RW_READER); 853 blkid = dbuf_whichblock(dn, offset); 854 VERIFY((db = dbuf_hold(dn, blkid, FTAG)) != NULL); 855 rw_exit(&dn->dn_struct_rwlock); 856 857 if (offset == db->db.db_offset && blksz == db->db.db_size) { 858 dbuf_assign_arcbuf(db, buf, tx); 859 dbuf_rele(db, FTAG); 860 } else { 861 dbuf_rele(db, FTAG); 862 ASSERT(dn->dn_objset->os.os == dn->dn_objset); 863 dmu_write(&dn->dn_objset->os, dn->dn_object, offset, blksz, 864 buf->b_data, tx); 865 dmu_return_arcbuf(buf); 866 } 867 } 868 869 typedef struct { 870 dbuf_dirty_record_t *dr; 871 dmu_sync_cb_t *done; 872 void *arg; 873 } dmu_sync_arg_t; 874 875 /* ARGSUSED */ 876 static void 877 dmu_sync_ready(zio_t *zio, arc_buf_t *buf, void *varg) 878 { 879 blkptr_t *bp = zio->io_bp; 880 881 if (!BP_IS_HOLE(bp)) { 882 dmu_sync_arg_t *in = varg; 883 dbuf_dirty_record_t *dr = in->dr; 884 dmu_buf_impl_t *db = dr->dr_dbuf; 885 ASSERT(BP_GET_TYPE(bp) == db->db_dnode->dn_type); 886 ASSERT(BP_GET_LEVEL(bp) == 0); 887 bp->blk_fill = 1; 888 } 889 } 890 891 /* ARGSUSED */ 892 static void 893 dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg) 894 { 895 dmu_sync_arg_t *in = varg; 896 dbuf_dirty_record_t *dr = in->dr; 897 dmu_buf_impl_t *db = dr->dr_dbuf; 898 dmu_sync_cb_t *done = in->done; 899 900 mutex_enter(&db->db_mtx); 901 ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC); 902 dr->dt.dl.dr_overridden_by = *zio->io_bp; /* structure assignment */ 903 dr->dt.dl.dr_override_state = DR_OVERRIDDEN; 904 cv_broadcast(&db->db_changed); 905 mutex_exit(&db->db_mtx); 906 907 if (done) 908 done(&(db->db), in->arg); 909 910 kmem_free(in, sizeof (dmu_sync_arg_t)); 911 } 912 913 /* 914 * Intent log support: sync the block associated with db to disk. 915 * N.B. and XXX: the caller is responsible for making sure that the 916 * data isn't changing while dmu_sync() is writing it. 917 * 918 * Return values: 919 * 920 * EEXIST: this txg has already been synced, so there's nothing to to. 921 * The caller should not log the write. 922 * 923 * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do. 924 * The caller should not log the write. 925 * 926 * EALREADY: this block is already in the process of being synced. 927 * The caller should track its progress (somehow). 928 * 929 * EINPROGRESS: the IO has been initiated. 930 * The caller should log this blkptr in the callback. 931 * 932 * 0: completed. Sets *bp to the blkptr just written. 933 * The caller should log this blkptr immediately. 934 */ 935 int 936 dmu_sync(zio_t *pio, dmu_buf_t *db_fake, 937 blkptr_t *bp, uint64_t txg, dmu_sync_cb_t *done, void *arg) 938 { 939 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 940 objset_impl_t *os = db->db_objset; 941 dsl_pool_t *dp = os->os_dsl_dataset->ds_dir->dd_pool; 942 tx_state_t *tx = &dp->dp_tx; 943 dbuf_dirty_record_t *dr; 944 dmu_sync_arg_t *in; 945 zbookmark_t zb; 946 writeprops_t wp = { 0 }; 947 zio_t *zio; 948 int err; 949 950 ASSERT(BP_IS_HOLE(bp)); 951 ASSERT(txg != 0); 952 953 dprintf("dmu_sync txg=%llu, s,o,q %llu %llu %llu\n", 954 txg, tx->tx_synced_txg, tx->tx_open_txg, tx->tx_quiesced_txg); 955 956 /* 957 * XXX - would be nice if we could do this without suspending... 958 */ 959 txg_suspend(dp); 960 961 /* 962 * If this txg already synced, there's nothing to do. 963 */ 964 if (txg <= tx->tx_synced_txg) { 965 txg_resume(dp); 966 /* 967 * If we're running ziltest, we need the blkptr regardless. 968 */ 969 if (txg > spa_freeze_txg(dp->dp_spa)) { 970 /* if db_blkptr == NULL, this was an empty write */ 971 if (db->db_blkptr) 972 *bp = *db->db_blkptr; /* structure assignment */ 973 return (0); 974 } 975 return (EEXIST); 976 } 977 978 mutex_enter(&db->db_mtx); 979 980 if (txg == tx->tx_syncing_txg) { 981 while (db->db_data_pending) { 982 /* 983 * IO is in-progress. Wait for it to finish. 984 * XXX - would be nice to be able to somehow "attach" 985 * this zio to the parent zio passed in. 986 */ 987 cv_wait(&db->db_changed, &db->db_mtx); 988 if (!db->db_data_pending && 989 db->db_blkptr && BP_IS_HOLE(db->db_blkptr)) { 990 /* 991 * IO was compressed away 992 */ 993 *bp = *db->db_blkptr; /* structure assignment */ 994 mutex_exit(&db->db_mtx); 995 txg_resume(dp); 996 return (0); 997 } 998 ASSERT(db->db_data_pending || 999 (db->db_blkptr && db->db_blkptr->blk_birth == txg)); 1000 } 1001 1002 if (db->db_blkptr && db->db_blkptr->blk_birth == txg) { 1003 /* 1004 * IO is already completed. 1005 */ 1006 *bp = *db->db_blkptr; /* structure assignment */ 1007 mutex_exit(&db->db_mtx); 1008 txg_resume(dp); 1009 return (0); 1010 } 1011 } 1012 1013 dr = db->db_last_dirty; 1014 while (dr && dr->dr_txg > txg) 1015 dr = dr->dr_next; 1016 if (dr == NULL || dr->dr_txg < txg) { 1017 /* 1018 * This dbuf isn't dirty, must have been free_range'd. 1019 * There's no need to log writes to freed blocks, so we're done. 1020 */ 1021 mutex_exit(&db->db_mtx); 1022 txg_resume(dp); 1023 return (ENOENT); 1024 } 1025 1026 ASSERT(dr->dr_txg == txg); 1027 if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC) { 1028 /* 1029 * We have already issued a sync write for this buffer. 1030 */ 1031 mutex_exit(&db->db_mtx); 1032 txg_resume(dp); 1033 return (EALREADY); 1034 } else if (dr->dt.dl.dr_override_state == DR_OVERRIDDEN) { 1035 /* 1036 * This buffer has already been synced. It could not 1037 * have been dirtied since, or we would have cleared the state. 1038 */ 1039 *bp = dr->dt.dl.dr_overridden_by; /* structure assignment */ 1040 mutex_exit(&db->db_mtx); 1041 txg_resume(dp); 1042 return (0); 1043 } 1044 1045 dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC; 1046 in = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP); 1047 in->dr = dr; 1048 in->done = done; 1049 in->arg = arg; 1050 mutex_exit(&db->db_mtx); 1051 txg_resume(dp); 1052 1053 zb.zb_objset = os->os_dsl_dataset->ds_object; 1054 zb.zb_object = db->db.db_object; 1055 zb.zb_level = db->db_level; 1056 zb.zb_blkid = db->db_blkid; 1057 1058 wp.wp_type = db->db_dnode->dn_type; 1059 wp.wp_level = db->db_level; 1060 wp.wp_copies = os->os_copies; 1061 wp.wp_dnchecksum = db->db_dnode->dn_checksum; 1062 wp.wp_oschecksum = os->os_checksum; 1063 wp.wp_dncompress = db->db_dnode->dn_compress; 1064 wp.wp_oscompress = os->os_compress; 1065 1066 ASSERT(BP_IS_HOLE(bp)); 1067 1068 zio = arc_write(pio, os->os_spa, &wp, DBUF_IS_L2CACHEABLE(db), 1069 txg, bp, dr->dt.dl.dr_data, dmu_sync_ready, dmu_sync_done, in, 1070 ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_MUSTSUCCEED, &zb); 1071 if (pio) { 1072 zio_nowait(zio); 1073 err = EINPROGRESS; 1074 } else { 1075 err = zio_wait(zio); 1076 ASSERT(err == 0); 1077 } 1078 return (err); 1079 } 1080 1081 int 1082 dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs, 1083 dmu_tx_t *tx) 1084 { 1085 dnode_t *dn; 1086 int err; 1087 1088 err = dnode_hold(os->os, object, FTAG, &dn); 1089 if (err) 1090 return (err); 1091 err = dnode_set_blksz(dn, size, ibs, tx); 1092 dnode_rele(dn, FTAG); 1093 return (err); 1094 } 1095 1096 void 1097 dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum, 1098 dmu_tx_t *tx) 1099 { 1100 dnode_t *dn; 1101 1102 /* XXX assumes dnode_hold will not get an i/o error */ 1103 (void) dnode_hold(os->os, object, FTAG, &dn); 1104 ASSERT(checksum < ZIO_CHECKSUM_FUNCTIONS); 1105 dn->dn_checksum = checksum; 1106 dnode_setdirty(dn, tx); 1107 dnode_rele(dn, FTAG); 1108 } 1109 1110 void 1111 dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress, 1112 dmu_tx_t *tx) 1113 { 1114 dnode_t *dn; 1115 1116 /* XXX assumes dnode_hold will not get an i/o error */ 1117 (void) dnode_hold(os->os, object, FTAG, &dn); 1118 ASSERT(compress < ZIO_COMPRESS_FUNCTIONS); 1119 dn->dn_compress = compress; 1120 dnode_setdirty(dn, tx); 1121 dnode_rele(dn, FTAG); 1122 } 1123 1124 int 1125 dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off) 1126 { 1127 dnode_t *dn; 1128 int i, err; 1129 1130 err = dnode_hold(os->os, object, FTAG, &dn); 1131 if (err) 1132 return (err); 1133 /* 1134 * Sync any current changes before 1135 * we go trundling through the block pointers. 1136 */ 1137 for (i = 0; i < TXG_SIZE; i++) { 1138 if (list_link_active(&dn->dn_dirty_link[i])) 1139 break; 1140 } 1141 if (i != TXG_SIZE) { 1142 dnode_rele(dn, FTAG); 1143 txg_wait_synced(dmu_objset_pool(os), 0); 1144 err = dnode_hold(os->os, object, FTAG, &dn); 1145 if (err) 1146 return (err); 1147 } 1148 1149 err = dnode_next_offset(dn, (hole ? DNODE_FIND_HOLE : 0), off, 1, 1, 0); 1150 dnode_rele(dn, FTAG); 1151 1152 return (err); 1153 } 1154 1155 void 1156 dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi) 1157 { 1158 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1159 mutex_enter(&dn->dn_mtx); 1160 1161 doi->doi_data_block_size = dn->dn_datablksz; 1162 doi->doi_metadata_block_size = dn->dn_indblkshift ? 1163 1ULL << dn->dn_indblkshift : 0; 1164 doi->doi_indirection = dn->dn_nlevels; 1165 doi->doi_checksum = dn->dn_checksum; 1166 doi->doi_compress = dn->dn_compress; 1167 doi->doi_physical_blks = (DN_USED_BYTES(dn->dn_phys) + 1168 SPA_MINBLOCKSIZE/2) >> SPA_MINBLOCKSHIFT; 1169 doi->doi_max_block_offset = dn->dn_phys->dn_maxblkid; 1170 doi->doi_type = dn->dn_type; 1171 doi->doi_bonus_size = dn->dn_bonuslen; 1172 doi->doi_bonus_type = dn->dn_bonustype; 1173 1174 mutex_exit(&dn->dn_mtx); 1175 rw_exit(&dn->dn_struct_rwlock); 1176 } 1177 1178 /* 1179 * Get information on a DMU object. 1180 * If doi is NULL, just indicates whether the object exists. 1181 */ 1182 int 1183 dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi) 1184 { 1185 dnode_t *dn; 1186 int err = dnode_hold(os->os, object, FTAG, &dn); 1187 1188 if (err) 1189 return (err); 1190 1191 if (doi != NULL) 1192 dmu_object_info_from_dnode(dn, doi); 1193 1194 dnode_rele(dn, FTAG); 1195 return (0); 1196 } 1197 1198 /* 1199 * As above, but faster; can be used when you have a held dbuf in hand. 1200 */ 1201 void 1202 dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi) 1203 { 1204 dmu_object_info_from_dnode(((dmu_buf_impl_t *)db)->db_dnode, doi); 1205 } 1206 1207 /* 1208 * Faster still when you only care about the size. 1209 * This is specifically optimized for zfs_getattr(). 1210 */ 1211 void 1212 dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize, u_longlong_t *nblk512) 1213 { 1214 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode; 1215 1216 *blksize = dn->dn_datablksz; 1217 /* add 1 for dnode space */ 1218 *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >> 1219 SPA_MINBLOCKSHIFT) + 1; 1220 } 1221 1222 void 1223 byteswap_uint64_array(void *vbuf, size_t size) 1224 { 1225 uint64_t *buf = vbuf; 1226 size_t count = size >> 3; 1227 int i; 1228 1229 ASSERT((size & 7) == 0); 1230 1231 for (i = 0; i < count; i++) 1232 buf[i] = BSWAP_64(buf[i]); 1233 } 1234 1235 void 1236 byteswap_uint32_array(void *vbuf, size_t size) 1237 { 1238 uint32_t *buf = vbuf; 1239 size_t count = size >> 2; 1240 int i; 1241 1242 ASSERT((size & 3) == 0); 1243 1244 for (i = 0; i < count; i++) 1245 buf[i] = BSWAP_32(buf[i]); 1246 } 1247 1248 void 1249 byteswap_uint16_array(void *vbuf, size_t size) 1250 { 1251 uint16_t *buf = vbuf; 1252 size_t count = size >> 1; 1253 int i; 1254 1255 ASSERT((size & 1) == 0); 1256 1257 for (i = 0; i < count; i++) 1258 buf[i] = BSWAP_16(buf[i]); 1259 } 1260 1261 /* ARGSUSED */ 1262 void 1263 byteswap_uint8_array(void *vbuf, size_t size) 1264 { 1265 } 1266 1267 void 1268 dmu_init(void) 1269 { 1270 dbuf_init(); 1271 dnode_init(); 1272 arc_init(); 1273 l2arc_init(); 1274 } 1275 1276 void 1277 dmu_fini(void) 1278 { 1279 arc_fini(); 1280 dnode_fini(); 1281 dbuf_fini(); 1282 l2arc_fini(); 1283 } 1284