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 { zap_byteswap, TRUE, "snapshot refcount tags"}, 91 }; 92 93 int 94 dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset, 95 void *tag, dmu_buf_t **dbp) 96 { 97 dnode_t *dn; 98 uint64_t blkid; 99 dmu_buf_impl_t *db; 100 int err; 101 102 err = dnode_hold(os, object, FTAG, &dn); 103 if (err) 104 return (err); 105 blkid = dbuf_whichblock(dn, offset); 106 rw_enter(&dn->dn_struct_rwlock, RW_READER); 107 db = dbuf_hold(dn, blkid, tag); 108 rw_exit(&dn->dn_struct_rwlock); 109 if (db == NULL) { 110 err = EIO; 111 } else { 112 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 113 if (err) { 114 dbuf_rele(db, tag); 115 db = NULL; 116 } 117 } 118 119 dnode_rele(dn, FTAG); 120 *dbp = &db->db; 121 return (err); 122 } 123 124 int 125 dmu_bonus_max(void) 126 { 127 return (DN_MAX_BONUSLEN); 128 } 129 130 int 131 dmu_set_bonus(dmu_buf_t *db, int newsize, dmu_tx_t *tx) 132 { 133 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode; 134 135 if (dn->dn_bonus != (dmu_buf_impl_t *)db) 136 return (EINVAL); 137 if (newsize < 0 || newsize > db->db_size) 138 return (EINVAL); 139 dnode_setbonuslen(dn, newsize, tx); 140 return (0); 141 } 142 143 /* 144 * returns ENOENT, EIO, or 0. 145 */ 146 int 147 dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **dbp) 148 { 149 dnode_t *dn; 150 dmu_buf_impl_t *db; 151 int error; 152 153 error = dnode_hold(os, object, FTAG, &dn); 154 if (error) 155 return (error); 156 157 rw_enter(&dn->dn_struct_rwlock, RW_READER); 158 if (dn->dn_bonus == NULL) { 159 rw_exit(&dn->dn_struct_rwlock); 160 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 161 if (dn->dn_bonus == NULL) 162 dbuf_create_bonus(dn); 163 } 164 db = dn->dn_bonus; 165 rw_exit(&dn->dn_struct_rwlock); 166 167 /* as long as the bonus buf is held, the dnode will be held */ 168 if (refcount_add(&db->db_holds, tag) == 1) 169 VERIFY(dnode_add_ref(dn, db)); 170 171 dnode_rele(dn, FTAG); 172 173 VERIFY(0 == dbuf_read(db, NULL, DB_RF_MUST_SUCCEED)); 174 175 *dbp = &db->db; 176 return (0); 177 } 178 179 /* 180 * Note: longer-term, we should modify all of the dmu_buf_*() interfaces 181 * to take a held dnode rather than <os, object> -- the lookup is wasteful, 182 * and can induce severe lock contention when writing to several files 183 * whose dnodes are in the same block. 184 */ 185 static int 186 dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, uint64_t length, 187 int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp, uint32_t flags) 188 { 189 dsl_pool_t *dp = NULL; 190 dmu_buf_t **dbp; 191 uint64_t blkid, nblks, i; 192 uint32_t dbuf_flags; 193 int err; 194 zio_t *zio; 195 hrtime_t start; 196 197 ASSERT(length <= DMU_MAX_ACCESS); 198 199 dbuf_flags = DB_RF_CANFAIL | DB_RF_NEVERWAIT | DB_RF_HAVESTRUCT; 200 if (flags & DMU_READ_NO_PREFETCH || length > zfetch_array_rd_sz) 201 dbuf_flags |= DB_RF_NOPREFETCH; 202 203 rw_enter(&dn->dn_struct_rwlock, RW_READER); 204 if (dn->dn_datablkshift) { 205 int blkshift = dn->dn_datablkshift; 206 nblks = (P2ROUNDUP(offset+length, 1ULL<<blkshift) - 207 P2ALIGN(offset, 1ULL<<blkshift)) >> blkshift; 208 } else { 209 if (offset + length > dn->dn_datablksz) { 210 zfs_panic_recover("zfs: accessing past end of object " 211 "%llx/%llx (size=%u access=%llu+%llu)", 212 (longlong_t)dn->dn_objset-> 213 os_dsl_dataset->ds_object, 214 (longlong_t)dn->dn_object, dn->dn_datablksz, 215 (longlong_t)offset, (longlong_t)length); 216 rw_exit(&dn->dn_struct_rwlock); 217 return (EIO); 218 } 219 nblks = 1; 220 } 221 dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_SLEEP); 222 223 if (dn->dn_objset->os_dsl_dataset) 224 dp = dn->dn_objset->os_dsl_dataset->ds_dir->dd_pool; 225 if (dp && dsl_pool_sync_context(dp)) 226 start = gethrtime(); 227 zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, ZIO_FLAG_CANFAIL); 228 blkid = dbuf_whichblock(dn, offset); 229 for (i = 0; i < nblks; i++) { 230 dmu_buf_impl_t *db = dbuf_hold(dn, blkid+i, tag); 231 if (db == NULL) { 232 rw_exit(&dn->dn_struct_rwlock); 233 dmu_buf_rele_array(dbp, nblks, tag); 234 zio_nowait(zio); 235 return (EIO); 236 } 237 /* initiate async i/o */ 238 if (read) { 239 (void) dbuf_read(db, zio, dbuf_flags); 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, 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, DMU_READ_PREFETCH); 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, DMU_READ_PREFETCH); 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_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, 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 /* 380 * Get the next "chunk" of file data to free. We traverse the file from 381 * the end so that the file gets shorter over time (if we crashes in the 382 * middle, this will leave us in a better state). We find allocated file 383 * data by simply searching the allocated level 1 indirects. 384 */ 385 static int 386 get_next_chunk(dnode_t *dn, uint64_t *start, uint64_t limit) 387 { 388 uint64_t len = *start - limit; 389 uint64_t blkcnt = 0; 390 uint64_t maxblks = DMU_MAX_ACCESS / (1ULL << (dn->dn_indblkshift + 1)); 391 uint64_t iblkrange = 392 dn->dn_datablksz * EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT); 393 394 ASSERT(limit <= *start); 395 396 if (len <= iblkrange * maxblks) { 397 *start = limit; 398 return (0); 399 } 400 ASSERT(ISP2(iblkrange)); 401 402 while (*start > limit && blkcnt < maxblks) { 403 int err; 404 405 /* find next allocated L1 indirect */ 406 err = dnode_next_offset(dn, 407 DNODE_FIND_BACKWARDS, start, 2, 1, 0); 408 409 /* if there are no more, then we are done */ 410 if (err == ESRCH) { 411 *start = limit; 412 return (0); 413 } else if (err) { 414 return (err); 415 } 416 blkcnt += 1; 417 418 /* reset offset to end of "next" block back */ 419 *start = P2ALIGN(*start, iblkrange); 420 if (*start <= limit) 421 *start = limit; 422 else 423 *start -= 1; 424 } 425 return (0); 426 } 427 428 static int 429 dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset, 430 uint64_t length, boolean_t free_dnode) 431 { 432 dmu_tx_t *tx; 433 uint64_t object_size, start, end, len; 434 boolean_t trunc = (length == DMU_OBJECT_END); 435 int align, err; 436 437 align = 1 << dn->dn_datablkshift; 438 ASSERT(align > 0); 439 object_size = align == 1 ? dn->dn_datablksz : 440 (dn->dn_maxblkid + 1) << dn->dn_datablkshift; 441 442 end = offset + length; 443 if (trunc || end > object_size) 444 end = object_size; 445 if (end <= offset) 446 return (0); 447 length = end - offset; 448 449 while (length) { 450 start = end; 451 /* assert(offset <= start) */ 452 err = get_next_chunk(dn, &start, offset); 453 if (err) 454 return (err); 455 len = trunc ? DMU_OBJECT_END : end - start; 456 457 tx = dmu_tx_create(os); 458 dmu_tx_hold_free(tx, dn->dn_object, start, len); 459 err = dmu_tx_assign(tx, TXG_WAIT); 460 if (err) { 461 dmu_tx_abort(tx); 462 return (err); 463 } 464 465 dnode_free_range(dn, start, trunc ? -1 : len, tx); 466 467 if (start == 0 && free_dnode) { 468 ASSERT(trunc); 469 dnode_free(dn, tx); 470 } 471 472 length -= end - start; 473 474 dmu_tx_commit(tx); 475 end = start; 476 } 477 return (0); 478 } 479 480 int 481 dmu_free_long_range(objset_t *os, uint64_t object, 482 uint64_t offset, uint64_t length) 483 { 484 dnode_t *dn; 485 int err; 486 487 err = dnode_hold(os, object, FTAG, &dn); 488 if (err != 0) 489 return (err); 490 err = dmu_free_long_range_impl(os, dn, offset, length, FALSE); 491 dnode_rele(dn, FTAG); 492 return (err); 493 } 494 495 int 496 dmu_free_object(objset_t *os, uint64_t object) 497 { 498 dnode_t *dn; 499 dmu_tx_t *tx; 500 int err; 501 502 err = dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, 503 FTAG, &dn); 504 if (err != 0) 505 return (err); 506 if (dn->dn_nlevels == 1) { 507 tx = dmu_tx_create(os); 508 dmu_tx_hold_bonus(tx, object); 509 dmu_tx_hold_free(tx, dn->dn_object, 0, DMU_OBJECT_END); 510 err = dmu_tx_assign(tx, TXG_WAIT); 511 if (err == 0) { 512 dnode_free_range(dn, 0, DMU_OBJECT_END, tx); 513 dnode_free(dn, tx); 514 dmu_tx_commit(tx); 515 } else { 516 dmu_tx_abort(tx); 517 } 518 } else { 519 err = dmu_free_long_range_impl(os, dn, 0, DMU_OBJECT_END, TRUE); 520 } 521 dnode_rele(dn, FTAG); 522 return (err); 523 } 524 525 int 526 dmu_free_range(objset_t *os, uint64_t object, uint64_t offset, 527 uint64_t size, dmu_tx_t *tx) 528 { 529 dnode_t *dn; 530 int err = dnode_hold(os, object, FTAG, &dn); 531 if (err) 532 return (err); 533 ASSERT(offset < UINT64_MAX); 534 ASSERT(size == -1ULL || size <= UINT64_MAX - offset); 535 dnode_free_range(dn, offset, size, tx); 536 dnode_rele(dn, FTAG); 537 return (0); 538 } 539 540 int 541 dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 542 void *buf, uint32_t flags) 543 { 544 dnode_t *dn; 545 dmu_buf_t **dbp; 546 int numbufs, err; 547 548 err = dnode_hold(os, object, FTAG, &dn); 549 if (err) 550 return (err); 551 552 /* 553 * Deal with odd block sizes, where there can't be data past the first 554 * block. If we ever do the tail block optimization, we will need to 555 * handle that here as well. 556 */ 557 if (dn->dn_maxblkid == 0) { 558 int newsz = offset > dn->dn_datablksz ? 0 : 559 MIN(size, dn->dn_datablksz - offset); 560 bzero((char *)buf + newsz, size - newsz); 561 size = newsz; 562 } 563 564 while (size > 0) { 565 uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2); 566 int i; 567 568 /* 569 * NB: we could do this block-at-a-time, but it's nice 570 * to be reading in parallel. 571 */ 572 err = dmu_buf_hold_array_by_dnode(dn, offset, mylen, 573 TRUE, FTAG, &numbufs, &dbp, flags); 574 if (err) 575 break; 576 577 for (i = 0; i < numbufs; i++) { 578 int tocpy; 579 int bufoff; 580 dmu_buf_t *db = dbp[i]; 581 582 ASSERT(size > 0); 583 584 bufoff = offset - db->db_offset; 585 tocpy = (int)MIN(db->db_size - bufoff, size); 586 587 bcopy((char *)db->db_data + bufoff, buf, tocpy); 588 589 offset += tocpy; 590 size -= tocpy; 591 buf = (char *)buf + tocpy; 592 } 593 dmu_buf_rele_array(dbp, numbufs, FTAG); 594 } 595 dnode_rele(dn, FTAG); 596 return (err); 597 } 598 599 void 600 dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 601 const void *buf, dmu_tx_t *tx) 602 { 603 dmu_buf_t **dbp; 604 int numbufs, i; 605 606 if (size == 0) 607 return; 608 609 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size, 610 FALSE, FTAG, &numbufs, &dbp)); 611 612 for (i = 0; i < numbufs; i++) { 613 int tocpy; 614 int bufoff; 615 dmu_buf_t *db = dbp[i]; 616 617 ASSERT(size > 0); 618 619 bufoff = offset - db->db_offset; 620 tocpy = (int)MIN(db->db_size - bufoff, size); 621 622 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 623 624 if (tocpy == db->db_size) 625 dmu_buf_will_fill(db, tx); 626 else 627 dmu_buf_will_dirty(db, tx); 628 629 bcopy(buf, (char *)db->db_data + bufoff, tocpy); 630 631 if (tocpy == db->db_size) 632 dmu_buf_fill_done(db, tx); 633 634 offset += tocpy; 635 size -= tocpy; 636 buf = (char *)buf + tocpy; 637 } 638 dmu_buf_rele_array(dbp, numbufs, FTAG); 639 } 640 641 void 642 dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 643 dmu_tx_t *tx) 644 { 645 dmu_buf_t **dbp; 646 int numbufs, i; 647 648 if (size == 0) 649 return; 650 651 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size, 652 FALSE, FTAG, &numbufs, &dbp)); 653 654 for (i = 0; i < numbufs; i++) { 655 dmu_buf_t *db = dbp[i]; 656 657 dmu_buf_will_not_fill(db, tx); 658 } 659 dmu_buf_rele_array(dbp, numbufs, FTAG); 660 } 661 662 #ifdef _KERNEL 663 int 664 dmu_read_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size) 665 { 666 dmu_buf_t **dbp; 667 int numbufs, i, err; 668 669 /* 670 * NB: we could do this block-at-a-time, but it's nice 671 * to be reading in parallel. 672 */ 673 err = dmu_buf_hold_array(os, object, uio->uio_loffset, size, TRUE, FTAG, 674 &numbufs, &dbp); 675 if (err) 676 return (err); 677 678 for (i = 0; i < numbufs; i++) { 679 int tocpy; 680 int bufoff; 681 dmu_buf_t *db = dbp[i]; 682 683 ASSERT(size > 0); 684 685 bufoff = uio->uio_loffset - db->db_offset; 686 tocpy = (int)MIN(db->db_size - bufoff, size); 687 688 err = uiomove((char *)db->db_data + bufoff, tocpy, 689 UIO_READ, uio); 690 if (err) 691 break; 692 693 size -= tocpy; 694 } 695 dmu_buf_rele_array(dbp, numbufs, FTAG); 696 697 return (err); 698 } 699 700 int 701 dmu_write_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size, 702 dmu_tx_t *tx) 703 { 704 dmu_buf_t **dbp; 705 int numbufs, i; 706 int err = 0; 707 708 if (size == 0) 709 return (0); 710 711 err = dmu_buf_hold_array(os, object, uio->uio_loffset, size, 712 FALSE, FTAG, &numbufs, &dbp); 713 if (err) 714 return (err); 715 716 for (i = 0; i < numbufs; i++) { 717 int tocpy; 718 int bufoff; 719 dmu_buf_t *db = dbp[i]; 720 721 ASSERT(size > 0); 722 723 bufoff = uio->uio_loffset - db->db_offset; 724 tocpy = (int)MIN(db->db_size - bufoff, size); 725 726 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 727 728 if (tocpy == db->db_size) 729 dmu_buf_will_fill(db, tx); 730 else 731 dmu_buf_will_dirty(db, tx); 732 733 /* 734 * XXX uiomove could block forever (eg. nfs-backed 735 * pages). There needs to be a uiolockdown() function 736 * to lock the pages in memory, so that uiomove won't 737 * block. 738 */ 739 err = uiomove((char *)db->db_data + bufoff, tocpy, 740 UIO_WRITE, uio); 741 742 if (tocpy == db->db_size) 743 dmu_buf_fill_done(db, tx); 744 745 if (err) 746 break; 747 748 size -= tocpy; 749 } 750 dmu_buf_rele_array(dbp, numbufs, FTAG); 751 return (err); 752 } 753 754 int 755 dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 756 page_t *pp, dmu_tx_t *tx) 757 { 758 dmu_buf_t **dbp; 759 int numbufs, i; 760 int err; 761 762 if (size == 0) 763 return (0); 764 765 err = dmu_buf_hold_array(os, object, offset, size, 766 FALSE, FTAG, &numbufs, &dbp); 767 if (err) 768 return (err); 769 770 for (i = 0; i < numbufs; i++) { 771 int tocpy, copied, thiscpy; 772 int bufoff; 773 dmu_buf_t *db = dbp[i]; 774 caddr_t va; 775 776 ASSERT(size > 0); 777 ASSERT3U(db->db_size, >=, PAGESIZE); 778 779 bufoff = offset - db->db_offset; 780 tocpy = (int)MIN(db->db_size - bufoff, size); 781 782 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 783 784 if (tocpy == db->db_size) 785 dmu_buf_will_fill(db, tx); 786 else 787 dmu_buf_will_dirty(db, tx); 788 789 for (copied = 0; copied < tocpy; copied += PAGESIZE) { 790 ASSERT3U(pp->p_offset, ==, db->db_offset + bufoff); 791 thiscpy = MIN(PAGESIZE, tocpy - copied); 792 va = zfs_map_page(pp, S_READ); 793 bcopy(va, (char *)db->db_data + bufoff, thiscpy); 794 zfs_unmap_page(pp, va); 795 pp = pp->p_next; 796 bufoff += PAGESIZE; 797 } 798 799 if (tocpy == db->db_size) 800 dmu_buf_fill_done(db, tx); 801 802 offset += tocpy; 803 size -= tocpy; 804 } 805 dmu_buf_rele_array(dbp, numbufs, FTAG); 806 return (err); 807 } 808 #endif 809 810 /* 811 * Allocate a loaned anonymous arc buffer. 812 */ 813 arc_buf_t * 814 dmu_request_arcbuf(dmu_buf_t *handle, int size) 815 { 816 dnode_t *dn = ((dmu_buf_impl_t *)handle)->db_dnode; 817 818 return (arc_loan_buf(dn->dn_objset->os_spa, size)); 819 } 820 821 /* 822 * Free a loaned arc buffer. 823 */ 824 void 825 dmu_return_arcbuf(arc_buf_t *buf) 826 { 827 arc_return_buf(buf, FTAG); 828 VERIFY(arc_buf_remove_ref(buf, FTAG) == 1); 829 } 830 831 /* 832 * When possible directly assign passed loaned arc buffer to a dbuf. 833 * If this is not possible copy the contents of passed arc buf via 834 * dmu_write(). 835 */ 836 void 837 dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, arc_buf_t *buf, 838 dmu_tx_t *tx) 839 { 840 dnode_t *dn = ((dmu_buf_impl_t *)handle)->db_dnode; 841 dmu_buf_impl_t *db; 842 uint32_t blksz = (uint32_t)arc_buf_size(buf); 843 uint64_t blkid; 844 845 rw_enter(&dn->dn_struct_rwlock, RW_READER); 846 blkid = dbuf_whichblock(dn, offset); 847 VERIFY((db = dbuf_hold(dn, blkid, FTAG)) != NULL); 848 rw_exit(&dn->dn_struct_rwlock); 849 850 if (offset == db->db.db_offset && blksz == db->db.db_size) { 851 dbuf_assign_arcbuf(db, buf, tx); 852 dbuf_rele(db, FTAG); 853 } else { 854 dbuf_rele(db, FTAG); 855 dmu_write(dn->dn_objset, dn->dn_object, offset, blksz, 856 buf->b_data, tx); 857 dmu_return_arcbuf(buf); 858 } 859 } 860 861 typedef struct { 862 dbuf_dirty_record_t *dr; 863 dmu_sync_cb_t *done; 864 void *arg; 865 } dmu_sync_arg_t; 866 867 /* ARGSUSED */ 868 static void 869 dmu_sync_ready(zio_t *zio, arc_buf_t *buf, void *varg) 870 { 871 blkptr_t *bp = zio->io_bp; 872 873 if (!BP_IS_HOLE(bp)) { 874 dmu_sync_arg_t *in = varg; 875 dbuf_dirty_record_t *dr = in->dr; 876 dmu_buf_impl_t *db = dr->dr_dbuf; 877 ASSERT(BP_GET_TYPE(bp) == db->db_dnode->dn_type); 878 ASSERT(BP_GET_LEVEL(bp) == 0); 879 bp->blk_fill = 1; 880 } 881 } 882 883 /* ARGSUSED */ 884 static void 885 dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg) 886 { 887 dmu_sync_arg_t *in = varg; 888 dbuf_dirty_record_t *dr = in->dr; 889 dmu_buf_impl_t *db = dr->dr_dbuf; 890 dmu_sync_cb_t *done = in->done; 891 892 mutex_enter(&db->db_mtx); 893 ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC); 894 dr->dt.dl.dr_overridden_by = *zio->io_bp; /* structure assignment */ 895 dr->dt.dl.dr_override_state = DR_OVERRIDDEN; 896 cv_broadcast(&db->db_changed); 897 mutex_exit(&db->db_mtx); 898 899 if (done) 900 done(&(db->db), in->arg); 901 902 kmem_free(in, sizeof (dmu_sync_arg_t)); 903 } 904 905 /* 906 * Intent log support: sync the block associated with db to disk. 907 * N.B. and XXX: the caller is responsible for making sure that the 908 * data isn't changing while dmu_sync() is writing it. 909 * 910 * Return values: 911 * 912 * EEXIST: this txg has already been synced, so there's nothing to to. 913 * The caller should not log the write. 914 * 915 * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do. 916 * The caller should not log the write. 917 * 918 * EALREADY: this block is already in the process of being synced. 919 * The caller should track its progress (somehow). 920 * 921 * EINPROGRESS: the IO has been initiated. 922 * The caller should log this blkptr in the callback. 923 * 924 * 0: completed. Sets *bp to the blkptr just written. 925 * The caller should log this blkptr immediately. 926 */ 927 int 928 dmu_sync(zio_t *pio, dmu_buf_t *db_fake, 929 blkptr_t *bp, uint64_t txg, dmu_sync_cb_t *done, void *arg) 930 { 931 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 932 objset_t *os = db->db_objset; 933 dsl_pool_t *dp = os->os_dsl_dataset->ds_dir->dd_pool; 934 tx_state_t *tx = &dp->dp_tx; 935 dbuf_dirty_record_t *dr; 936 dmu_sync_arg_t *in; 937 zbookmark_t zb; 938 writeprops_t wp = { 0 }; 939 zio_t *zio; 940 int err; 941 942 ASSERT(BP_IS_HOLE(bp)); 943 ASSERT(txg != 0); 944 945 dprintf("dmu_sync txg=%llu, s,o,q %llu %llu %llu\n", 946 txg, tx->tx_synced_txg, tx->tx_open_txg, tx->tx_quiesced_txg); 947 948 /* 949 * XXX - would be nice if we could do this without suspending... 950 */ 951 txg_suspend(dp); 952 953 /* 954 * If this txg already synced, there's nothing to do. 955 */ 956 if (txg <= tx->tx_synced_txg) { 957 txg_resume(dp); 958 /* 959 * If we're running ziltest, we need the blkptr regardless. 960 */ 961 if (txg > spa_freeze_txg(dp->dp_spa)) { 962 /* if db_blkptr == NULL, this was an empty write */ 963 if (db->db_blkptr) 964 *bp = *db->db_blkptr; /* structure assignment */ 965 return (0); 966 } 967 return (EEXIST); 968 } 969 970 mutex_enter(&db->db_mtx); 971 972 if (txg == tx->tx_syncing_txg) { 973 while (db->db_data_pending) { 974 /* 975 * IO is in-progress. Wait for it to finish. 976 * XXX - would be nice to be able to somehow "attach" 977 * this zio to the parent zio passed in. 978 */ 979 cv_wait(&db->db_changed, &db->db_mtx); 980 if (!db->db_data_pending && 981 db->db_blkptr && BP_IS_HOLE(db->db_blkptr)) { 982 /* 983 * IO was compressed away 984 */ 985 *bp = *db->db_blkptr; /* structure assignment */ 986 mutex_exit(&db->db_mtx); 987 txg_resume(dp); 988 return (0); 989 } 990 ASSERT(db->db_data_pending || 991 (db->db_blkptr && db->db_blkptr->blk_birth == txg)); 992 } 993 994 if (db->db_blkptr && db->db_blkptr->blk_birth == txg) { 995 /* 996 * IO is already completed. 997 */ 998 *bp = *db->db_blkptr; /* structure assignment */ 999 mutex_exit(&db->db_mtx); 1000 txg_resume(dp); 1001 return (0); 1002 } 1003 } 1004 1005 dr = db->db_last_dirty; 1006 while (dr && dr->dr_txg > txg) 1007 dr = dr->dr_next; 1008 if (dr == NULL || dr->dr_txg < txg) { 1009 /* 1010 * This dbuf isn't dirty, must have been free_range'd. 1011 * There's no need to log writes to freed blocks, so we're done. 1012 */ 1013 mutex_exit(&db->db_mtx); 1014 txg_resume(dp); 1015 return (ENOENT); 1016 } 1017 1018 ASSERT(dr->dr_txg == txg); 1019 if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC) { 1020 /* 1021 * We have already issued a sync write for this buffer. 1022 */ 1023 mutex_exit(&db->db_mtx); 1024 txg_resume(dp); 1025 return (EALREADY); 1026 } else if (dr->dt.dl.dr_override_state == DR_OVERRIDDEN) { 1027 /* 1028 * This buffer has already been synced. It could not 1029 * have been dirtied since, or we would have cleared the state. 1030 */ 1031 *bp = dr->dt.dl.dr_overridden_by; /* structure assignment */ 1032 mutex_exit(&db->db_mtx); 1033 txg_resume(dp); 1034 return (0); 1035 } 1036 1037 dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC; 1038 in = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP); 1039 in->dr = dr; 1040 in->done = done; 1041 in->arg = arg; 1042 mutex_exit(&db->db_mtx); 1043 txg_resume(dp); 1044 1045 zb.zb_objset = os->os_dsl_dataset->ds_object; 1046 zb.zb_object = db->db.db_object; 1047 zb.zb_level = db->db_level; 1048 zb.zb_blkid = db->db_blkid; 1049 1050 wp.wp_type = db->db_dnode->dn_type; 1051 wp.wp_level = db->db_level; 1052 wp.wp_copies = os->os_copies; 1053 wp.wp_dnchecksum = db->db_dnode->dn_checksum; 1054 wp.wp_oschecksum = os->os_checksum; 1055 wp.wp_dncompress = db->db_dnode->dn_compress; 1056 wp.wp_oscompress = os->os_compress; 1057 1058 ASSERT(BP_IS_HOLE(bp)); 1059 1060 zio = arc_write(pio, os->os_spa, &wp, DBUF_IS_L2CACHEABLE(db), 1061 txg, bp, dr->dt.dl.dr_data, dmu_sync_ready, dmu_sync_done, in, 1062 ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_MUSTSUCCEED, &zb); 1063 if (pio) { 1064 zio_nowait(zio); 1065 err = EINPROGRESS; 1066 } else { 1067 err = zio_wait(zio); 1068 ASSERT(err == 0); 1069 } 1070 return (err); 1071 } 1072 1073 int 1074 dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs, 1075 dmu_tx_t *tx) 1076 { 1077 dnode_t *dn; 1078 int err; 1079 1080 err = dnode_hold(os, object, FTAG, &dn); 1081 if (err) 1082 return (err); 1083 err = dnode_set_blksz(dn, size, ibs, tx); 1084 dnode_rele(dn, FTAG); 1085 return (err); 1086 } 1087 1088 void 1089 dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum, 1090 dmu_tx_t *tx) 1091 { 1092 dnode_t *dn; 1093 1094 /* XXX assumes dnode_hold will not get an i/o error */ 1095 (void) dnode_hold(os, object, FTAG, &dn); 1096 ASSERT(checksum < ZIO_CHECKSUM_FUNCTIONS); 1097 dn->dn_checksum = checksum; 1098 dnode_setdirty(dn, tx); 1099 dnode_rele(dn, FTAG); 1100 } 1101 1102 void 1103 dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress, 1104 dmu_tx_t *tx) 1105 { 1106 dnode_t *dn; 1107 1108 /* XXX assumes dnode_hold will not get an i/o error */ 1109 (void) dnode_hold(os, object, FTAG, &dn); 1110 ASSERT(compress < ZIO_COMPRESS_FUNCTIONS); 1111 dn->dn_compress = compress; 1112 dnode_setdirty(dn, tx); 1113 dnode_rele(dn, FTAG); 1114 } 1115 1116 int 1117 dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off) 1118 { 1119 dnode_t *dn; 1120 int i, err; 1121 1122 err = dnode_hold(os, object, FTAG, &dn); 1123 if (err) 1124 return (err); 1125 /* 1126 * Sync any current changes before 1127 * we go trundling through the block pointers. 1128 */ 1129 for (i = 0; i < TXG_SIZE; i++) { 1130 if (list_link_active(&dn->dn_dirty_link[i])) 1131 break; 1132 } 1133 if (i != TXG_SIZE) { 1134 dnode_rele(dn, FTAG); 1135 txg_wait_synced(dmu_objset_pool(os), 0); 1136 err = dnode_hold(os, object, FTAG, &dn); 1137 if (err) 1138 return (err); 1139 } 1140 1141 err = dnode_next_offset(dn, (hole ? DNODE_FIND_HOLE : 0), off, 1, 1, 0); 1142 dnode_rele(dn, FTAG); 1143 1144 return (err); 1145 } 1146 1147 void 1148 dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi) 1149 { 1150 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1151 mutex_enter(&dn->dn_mtx); 1152 1153 doi->doi_data_block_size = dn->dn_datablksz; 1154 doi->doi_metadata_block_size = dn->dn_indblkshift ? 1155 1ULL << dn->dn_indblkshift : 0; 1156 doi->doi_indirection = dn->dn_nlevels; 1157 doi->doi_checksum = dn->dn_checksum; 1158 doi->doi_compress = dn->dn_compress; 1159 doi->doi_physical_blks = (DN_USED_BYTES(dn->dn_phys) + 1160 SPA_MINBLOCKSIZE/2) >> SPA_MINBLOCKSHIFT; 1161 doi->doi_max_block_offset = dn->dn_phys->dn_maxblkid; 1162 doi->doi_type = dn->dn_type; 1163 doi->doi_bonus_size = dn->dn_bonuslen; 1164 doi->doi_bonus_type = dn->dn_bonustype; 1165 1166 mutex_exit(&dn->dn_mtx); 1167 rw_exit(&dn->dn_struct_rwlock); 1168 } 1169 1170 /* 1171 * Get information on a DMU object. 1172 * If doi is NULL, just indicates whether the object exists. 1173 */ 1174 int 1175 dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi) 1176 { 1177 dnode_t *dn; 1178 int err = dnode_hold(os, object, FTAG, &dn); 1179 1180 if (err) 1181 return (err); 1182 1183 if (doi != NULL) 1184 dmu_object_info_from_dnode(dn, doi); 1185 1186 dnode_rele(dn, FTAG); 1187 return (0); 1188 } 1189 1190 /* 1191 * As above, but faster; can be used when you have a held dbuf in hand. 1192 */ 1193 void 1194 dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi) 1195 { 1196 dmu_object_info_from_dnode(((dmu_buf_impl_t *)db)->db_dnode, doi); 1197 } 1198 1199 /* 1200 * Faster still when you only care about the size. 1201 * This is specifically optimized for zfs_getattr(). 1202 */ 1203 void 1204 dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize, u_longlong_t *nblk512) 1205 { 1206 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode; 1207 1208 *blksize = dn->dn_datablksz; 1209 /* add 1 for dnode space */ 1210 *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >> 1211 SPA_MINBLOCKSHIFT) + 1; 1212 } 1213 1214 void 1215 byteswap_uint64_array(void *vbuf, size_t size) 1216 { 1217 uint64_t *buf = vbuf; 1218 size_t count = size >> 3; 1219 int i; 1220 1221 ASSERT((size & 7) == 0); 1222 1223 for (i = 0; i < count; i++) 1224 buf[i] = BSWAP_64(buf[i]); 1225 } 1226 1227 void 1228 byteswap_uint32_array(void *vbuf, size_t size) 1229 { 1230 uint32_t *buf = vbuf; 1231 size_t count = size >> 2; 1232 int i; 1233 1234 ASSERT((size & 3) == 0); 1235 1236 for (i = 0; i < count; i++) 1237 buf[i] = BSWAP_32(buf[i]); 1238 } 1239 1240 void 1241 byteswap_uint16_array(void *vbuf, size_t size) 1242 { 1243 uint16_t *buf = vbuf; 1244 size_t count = size >> 1; 1245 int i; 1246 1247 ASSERT((size & 1) == 0); 1248 1249 for (i = 0; i < count; i++) 1250 buf[i] = BSWAP_16(buf[i]); 1251 } 1252 1253 /* ARGSUSED */ 1254 void 1255 byteswap_uint8_array(void *vbuf, size_t size) 1256 { 1257 } 1258 1259 void 1260 dmu_init(void) 1261 { 1262 dbuf_init(); 1263 dnode_init(); 1264 arc_init(); 1265 l2arc_init(); 1266 } 1267 1268 void 1269 dmu_fini(void) 1270 { 1271 arc_fini(); 1272 dnode_fini(); 1273 dbuf_fini(); 1274 l2arc_fini(); 1275 } 1276