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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * 24 * Portions Copyright 2010 Robert Milkowski 25 * 26 * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 27 * Copyright (c) 2012 by Delphix. All rights reserved. 28 */ 29 30 /* 31 * ZFS volume emulation driver. 32 * 33 * Makes a DMU object look like a volume of arbitrary size, up to 2^64 bytes. 34 * Volumes are accessed through the symbolic links named: 35 * 36 * /dev/zvol/dsk/<pool_name>/<dataset_name> 37 * /dev/zvol/rdsk/<pool_name>/<dataset_name> 38 * 39 * These links are created by the /dev filesystem (sdev_zvolops.c). 40 * Volumes are persistent through reboot. No user command needs to be 41 * run before opening and using a device. 42 */ 43 44 #include <sys/types.h> 45 #include <sys/param.h> 46 #include <sys/errno.h> 47 #include <sys/uio.h> 48 #include <sys/buf.h> 49 #include <sys/modctl.h> 50 #include <sys/open.h> 51 #include <sys/kmem.h> 52 #include <sys/conf.h> 53 #include <sys/cmn_err.h> 54 #include <sys/stat.h> 55 #include <sys/zap.h> 56 #include <sys/spa.h> 57 #include <sys/zio.h> 58 #include <sys/dmu_traverse.h> 59 #include <sys/dnode.h> 60 #include <sys/dsl_dataset.h> 61 #include <sys/dsl_prop.h> 62 #include <sys/dkio.h> 63 #include <sys/efi_partition.h> 64 #include <sys/byteorder.h> 65 #include <sys/pathname.h> 66 #include <sys/ddi.h> 67 #include <sys/sunddi.h> 68 #include <sys/crc32.h> 69 #include <sys/dirent.h> 70 #include <sys/policy.h> 71 #include <sys/fs/zfs.h> 72 #include <sys/zfs_ioctl.h> 73 #include <sys/mkdev.h> 74 #include <sys/zil.h> 75 #include <sys/refcount.h> 76 #include <sys/zfs_znode.h> 77 #include <sys/zfs_rlock.h> 78 #include <sys/vdev_disk.h> 79 #include <sys/vdev_impl.h> 80 #include <sys/zvol.h> 81 #include <sys/dumphdr.h> 82 #include <sys/zil_impl.h> 83 #include <sys/dbuf.h> 84 85 #include "zfs_namecheck.h" 86 87 void *zfsdev_state; 88 static char *zvol_tag = "zvol_tag"; 89 90 #define ZVOL_DUMPSIZE "dumpsize" 91 92 /* 93 * This lock protects the zfsdev_state structure from being modified 94 * while it's being used, e.g. an open that comes in before a create 95 * finishes. It also protects temporary opens of the dataset so that, 96 * e.g., an open doesn't get a spurious EBUSY. 97 */ 98 kmutex_t zfsdev_state_lock; 99 static uint32_t zvol_minors; 100 101 typedef struct zvol_extent { 102 list_node_t ze_node; 103 dva_t ze_dva; /* dva associated with this extent */ 104 uint64_t ze_nblks; /* number of blocks in extent */ 105 } zvol_extent_t; 106 107 /* 108 * The in-core state of each volume. 109 */ 110 typedef struct zvol_state { 111 char zv_name[MAXPATHLEN]; /* pool/dd name */ 112 uint64_t zv_volsize; /* amount of space we advertise */ 113 uint64_t zv_volblocksize; /* volume block size */ 114 minor_t zv_minor; /* minor number */ 115 uint8_t zv_min_bs; /* minimum addressable block shift */ 116 uint8_t zv_flags; /* readonly, dumpified, etc. */ 117 objset_t *zv_objset; /* objset handle */ 118 uint32_t zv_open_count[OTYPCNT]; /* open counts */ 119 uint32_t zv_total_opens; /* total open count */ 120 zilog_t *zv_zilog; /* ZIL handle */ 121 list_t zv_extents; /* List of extents for dump */ 122 znode_t zv_znode; /* for range locking */ 123 dmu_buf_t *zv_dbuf; /* bonus handle */ 124 } zvol_state_t; 125 126 /* 127 * zvol specific flags 128 */ 129 #define ZVOL_RDONLY 0x1 130 #define ZVOL_DUMPIFIED 0x2 131 #define ZVOL_EXCL 0x4 132 #define ZVOL_WCE 0x8 133 134 /* 135 * zvol maximum transfer in one DMU tx. 136 */ 137 int zvol_maxphys = DMU_MAX_ACCESS/2; 138 139 extern int zfs_set_prop_nvlist(const char *, zprop_source_t, 140 nvlist_t *, nvlist_t *); 141 static int zvol_remove_zv(zvol_state_t *); 142 static int zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio); 143 static int zvol_dumpify(zvol_state_t *zv); 144 static int zvol_dump_fini(zvol_state_t *zv); 145 static int zvol_dump_init(zvol_state_t *zv, boolean_t resize); 146 147 static void 148 zvol_size_changed(uint64_t volsize, major_t maj, minor_t min) 149 { 150 dev_t dev = makedevice(maj, min); 151 152 VERIFY(ddi_prop_update_int64(dev, zfs_dip, 153 "Size", volsize) == DDI_SUCCESS); 154 VERIFY(ddi_prop_update_int64(dev, zfs_dip, 155 "Nblocks", lbtodb(volsize)) == DDI_SUCCESS); 156 157 /* Notify specfs to invalidate the cached size */ 158 spec_size_invalidate(dev, VBLK); 159 spec_size_invalidate(dev, VCHR); 160 } 161 162 int 163 zvol_check_volsize(uint64_t volsize, uint64_t blocksize) 164 { 165 if (volsize == 0) 166 return (EINVAL); 167 168 if (volsize % blocksize != 0) 169 return (EINVAL); 170 171 #ifdef _ILP32 172 if (volsize - 1 > SPEC_MAXOFFSET_T) 173 return (EOVERFLOW); 174 #endif 175 return (0); 176 } 177 178 int 179 zvol_check_volblocksize(uint64_t volblocksize) 180 { 181 if (volblocksize < SPA_MINBLOCKSIZE || 182 volblocksize > SPA_MAXBLOCKSIZE || 183 !ISP2(volblocksize)) 184 return (EDOM); 185 186 return (0); 187 } 188 189 int 190 zvol_get_stats(objset_t *os, nvlist_t *nv) 191 { 192 int error; 193 dmu_object_info_t doi; 194 uint64_t val; 195 196 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val); 197 if (error) 198 return (error); 199 200 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val); 201 202 error = dmu_object_info(os, ZVOL_OBJ, &doi); 203 204 if (error == 0) { 205 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE, 206 doi.doi_data_block_size); 207 } 208 209 return (error); 210 } 211 212 static zvol_state_t * 213 zvol_minor_lookup(const char *name) 214 { 215 minor_t minor; 216 zvol_state_t *zv; 217 218 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 219 220 for (minor = 1; minor <= ZFSDEV_MAX_MINOR; minor++) { 221 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 222 if (zv == NULL) 223 continue; 224 if (strcmp(zv->zv_name, name) == 0) 225 return (zv); 226 } 227 228 return (NULL); 229 } 230 231 /* extent mapping arg */ 232 struct maparg { 233 zvol_state_t *ma_zv; 234 uint64_t ma_blks; 235 }; 236 237 /*ARGSUSED*/ 238 static int 239 zvol_map_block(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, arc_buf_t *pbuf, 240 const zbookmark_t *zb, const dnode_phys_t *dnp, void *arg) 241 { 242 struct maparg *ma = arg; 243 zvol_extent_t *ze; 244 int bs = ma->ma_zv->zv_volblocksize; 245 246 if (bp == NULL || zb->zb_object != ZVOL_OBJ || zb->zb_level != 0) 247 return (0); 248 249 VERIFY3U(ma->ma_blks, ==, zb->zb_blkid); 250 ma->ma_blks++; 251 252 /* Abort immediately if we have encountered gang blocks */ 253 if (BP_IS_GANG(bp)) 254 return (EFRAGS); 255 256 /* 257 * See if the block is at the end of the previous extent. 258 */ 259 ze = list_tail(&ma->ma_zv->zv_extents); 260 if (ze && 261 DVA_GET_VDEV(BP_IDENTITY(bp)) == DVA_GET_VDEV(&ze->ze_dva) && 262 DVA_GET_OFFSET(BP_IDENTITY(bp)) == 263 DVA_GET_OFFSET(&ze->ze_dva) + ze->ze_nblks * bs) { 264 ze->ze_nblks++; 265 return (0); 266 } 267 268 dprintf_bp(bp, "%s", "next blkptr:"); 269 270 /* start a new extent */ 271 ze = kmem_zalloc(sizeof (zvol_extent_t), KM_SLEEP); 272 ze->ze_dva = bp->blk_dva[0]; /* structure assignment */ 273 ze->ze_nblks = 1; 274 list_insert_tail(&ma->ma_zv->zv_extents, ze); 275 return (0); 276 } 277 278 static void 279 zvol_free_extents(zvol_state_t *zv) 280 { 281 zvol_extent_t *ze; 282 283 while (ze = list_head(&zv->zv_extents)) { 284 list_remove(&zv->zv_extents, ze); 285 kmem_free(ze, sizeof (zvol_extent_t)); 286 } 287 } 288 289 static int 290 zvol_get_lbas(zvol_state_t *zv) 291 { 292 objset_t *os = zv->zv_objset; 293 struct maparg ma; 294 int err; 295 296 ma.ma_zv = zv; 297 ma.ma_blks = 0; 298 zvol_free_extents(zv); 299 300 /* commit any in-flight changes before traversing the dataset */ 301 txg_wait_synced(dmu_objset_pool(os), 0); 302 err = traverse_dataset(dmu_objset_ds(os), 0, 303 TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA, zvol_map_block, &ma); 304 if (err || ma.ma_blks != (zv->zv_volsize / zv->zv_volblocksize)) { 305 zvol_free_extents(zv); 306 return (err ? err : EIO); 307 } 308 309 return (0); 310 } 311 312 /* ARGSUSED */ 313 void 314 zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx) 315 { 316 zfs_creat_t *zct = arg; 317 nvlist_t *nvprops = zct->zct_props; 318 int error; 319 uint64_t volblocksize, volsize; 320 321 VERIFY(nvlist_lookup_uint64(nvprops, 322 zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0); 323 if (nvlist_lookup_uint64(nvprops, 324 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0) 325 volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE); 326 327 /* 328 * These properties must be removed from the list so the generic 329 * property setting step won't apply to them. 330 */ 331 VERIFY(nvlist_remove_all(nvprops, 332 zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0); 333 (void) nvlist_remove_all(nvprops, 334 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE)); 335 336 error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize, 337 DMU_OT_NONE, 0, tx); 338 ASSERT(error == 0); 339 340 error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP, 341 DMU_OT_NONE, 0, tx); 342 ASSERT(error == 0); 343 344 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx); 345 ASSERT(error == 0); 346 } 347 348 /* 349 * Replay a TX_TRUNCATE ZIL transaction if asked. TX_TRUNCATE is how we 350 * implement DKIOCFREE/free-long-range. 351 */ 352 static int 353 zvol_replay_truncate(zvol_state_t *zv, lr_truncate_t *lr, boolean_t byteswap) 354 { 355 uint64_t offset, length; 356 357 if (byteswap) 358 byteswap_uint64_array(lr, sizeof (*lr)); 359 360 offset = lr->lr_offset; 361 length = lr->lr_length; 362 363 return (dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, offset, length)); 364 } 365 366 /* 367 * Replay a TX_WRITE ZIL transaction that didn't get committed 368 * after a system failure 369 */ 370 static int 371 zvol_replay_write(zvol_state_t *zv, lr_write_t *lr, boolean_t byteswap) 372 { 373 objset_t *os = zv->zv_objset; 374 char *data = (char *)(lr + 1); /* data follows lr_write_t */ 375 uint64_t offset, length; 376 dmu_tx_t *tx; 377 int error; 378 379 if (byteswap) 380 byteswap_uint64_array(lr, sizeof (*lr)); 381 382 offset = lr->lr_offset; 383 length = lr->lr_length; 384 385 /* If it's a dmu_sync() block, write the whole block */ 386 if (lr->lr_common.lrc_reclen == sizeof (lr_write_t)) { 387 uint64_t blocksize = BP_GET_LSIZE(&lr->lr_blkptr); 388 if (length < blocksize) { 389 offset -= offset % blocksize; 390 length = blocksize; 391 } 392 } 393 394 tx = dmu_tx_create(os); 395 dmu_tx_hold_write(tx, ZVOL_OBJ, offset, length); 396 error = dmu_tx_assign(tx, TXG_WAIT); 397 if (error) { 398 dmu_tx_abort(tx); 399 } else { 400 dmu_write(os, ZVOL_OBJ, offset, length, data, tx); 401 dmu_tx_commit(tx); 402 } 403 404 return (error); 405 } 406 407 /* ARGSUSED */ 408 static int 409 zvol_replay_err(zvol_state_t *zv, lr_t *lr, boolean_t byteswap) 410 { 411 return (ENOTSUP); 412 } 413 414 /* 415 * Callback vectors for replaying records. 416 * Only TX_WRITE and TX_TRUNCATE are needed for zvol. 417 */ 418 zil_replay_func_t *zvol_replay_vector[TX_MAX_TYPE] = { 419 zvol_replay_err, /* 0 no such transaction type */ 420 zvol_replay_err, /* TX_CREATE */ 421 zvol_replay_err, /* TX_MKDIR */ 422 zvol_replay_err, /* TX_MKXATTR */ 423 zvol_replay_err, /* TX_SYMLINK */ 424 zvol_replay_err, /* TX_REMOVE */ 425 zvol_replay_err, /* TX_RMDIR */ 426 zvol_replay_err, /* TX_LINK */ 427 zvol_replay_err, /* TX_RENAME */ 428 zvol_replay_write, /* TX_WRITE */ 429 zvol_replay_truncate, /* TX_TRUNCATE */ 430 zvol_replay_err, /* TX_SETATTR */ 431 zvol_replay_err, /* TX_ACL */ 432 zvol_replay_err, /* TX_CREATE_ACL */ 433 zvol_replay_err, /* TX_CREATE_ATTR */ 434 zvol_replay_err, /* TX_CREATE_ACL_ATTR */ 435 zvol_replay_err, /* TX_MKDIR_ACL */ 436 zvol_replay_err, /* TX_MKDIR_ATTR */ 437 zvol_replay_err, /* TX_MKDIR_ACL_ATTR */ 438 zvol_replay_err, /* TX_WRITE2 */ 439 }; 440 441 int 442 zvol_name2minor(const char *name, minor_t *minor) 443 { 444 zvol_state_t *zv; 445 446 mutex_enter(&zfsdev_state_lock); 447 zv = zvol_minor_lookup(name); 448 if (minor && zv) 449 *minor = zv->zv_minor; 450 mutex_exit(&zfsdev_state_lock); 451 return (zv ? 0 : -1); 452 } 453 454 /* 455 * Create a minor node (plus a whole lot more) for the specified volume. 456 */ 457 int 458 zvol_create_minor(const char *name) 459 { 460 zfs_soft_state_t *zs; 461 zvol_state_t *zv; 462 objset_t *os; 463 dmu_object_info_t doi; 464 minor_t minor = 0; 465 char chrbuf[30], blkbuf[30]; 466 int error; 467 468 mutex_enter(&zfsdev_state_lock); 469 470 if (zvol_minor_lookup(name) != NULL) { 471 mutex_exit(&zfsdev_state_lock); 472 return (EEXIST); 473 } 474 475 /* lie and say we're read-only */ 476 error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, FTAG, &os); 477 478 if (error) { 479 mutex_exit(&zfsdev_state_lock); 480 return (error); 481 } 482 483 if ((minor = zfsdev_minor_alloc()) == 0) { 484 dmu_objset_disown(os, FTAG); 485 mutex_exit(&zfsdev_state_lock); 486 return (ENXIO); 487 } 488 489 if (ddi_soft_state_zalloc(zfsdev_state, minor) != DDI_SUCCESS) { 490 dmu_objset_disown(os, FTAG); 491 mutex_exit(&zfsdev_state_lock); 492 return (EAGAIN); 493 } 494 (void) ddi_prop_update_string(minor, zfs_dip, ZVOL_PROP_NAME, 495 (char *)name); 496 497 (void) snprintf(chrbuf, sizeof (chrbuf), "%u,raw", minor); 498 499 if (ddi_create_minor_node(zfs_dip, chrbuf, S_IFCHR, 500 minor, DDI_PSEUDO, 0) == DDI_FAILURE) { 501 ddi_soft_state_free(zfsdev_state, minor); 502 dmu_objset_disown(os, FTAG); 503 mutex_exit(&zfsdev_state_lock); 504 return (EAGAIN); 505 } 506 507 (void) snprintf(blkbuf, sizeof (blkbuf), "%u", minor); 508 509 if (ddi_create_minor_node(zfs_dip, blkbuf, S_IFBLK, 510 minor, DDI_PSEUDO, 0) == DDI_FAILURE) { 511 ddi_remove_minor_node(zfs_dip, chrbuf); 512 ddi_soft_state_free(zfsdev_state, minor); 513 dmu_objset_disown(os, FTAG); 514 mutex_exit(&zfsdev_state_lock); 515 return (EAGAIN); 516 } 517 518 zs = ddi_get_soft_state(zfsdev_state, minor); 519 zs->zss_type = ZSST_ZVOL; 520 zv = zs->zss_data = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP); 521 (void) strlcpy(zv->zv_name, name, MAXPATHLEN); 522 zv->zv_min_bs = DEV_BSHIFT; 523 zv->zv_minor = minor; 524 zv->zv_objset = os; 525 if (dmu_objset_is_snapshot(os) || !spa_writeable(dmu_objset_spa(os))) 526 zv->zv_flags |= ZVOL_RDONLY; 527 mutex_init(&zv->zv_znode.z_range_lock, NULL, MUTEX_DEFAULT, NULL); 528 avl_create(&zv->zv_znode.z_range_avl, zfs_range_compare, 529 sizeof (rl_t), offsetof(rl_t, r_node)); 530 list_create(&zv->zv_extents, sizeof (zvol_extent_t), 531 offsetof(zvol_extent_t, ze_node)); 532 /* get and cache the blocksize */ 533 error = dmu_object_info(os, ZVOL_OBJ, &doi); 534 ASSERT(error == 0); 535 zv->zv_volblocksize = doi.doi_data_block_size; 536 537 if (spa_writeable(dmu_objset_spa(os))) { 538 if (zil_replay_disable) 539 zil_destroy(dmu_objset_zil(os), B_FALSE); 540 else 541 zil_replay(os, zv, zvol_replay_vector); 542 } 543 dmu_objset_disown(os, FTAG); 544 zv->zv_objset = NULL; 545 546 zvol_minors++; 547 548 mutex_exit(&zfsdev_state_lock); 549 550 return (0); 551 } 552 553 /* 554 * Remove minor node for the specified volume. 555 */ 556 static int 557 zvol_remove_zv(zvol_state_t *zv) 558 { 559 char nmbuf[20]; 560 minor_t minor = zv->zv_minor; 561 562 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 563 if (zv->zv_total_opens != 0) 564 return (EBUSY); 565 566 (void) snprintf(nmbuf, sizeof (nmbuf), "%u,raw", minor); 567 ddi_remove_minor_node(zfs_dip, nmbuf); 568 569 (void) snprintf(nmbuf, sizeof (nmbuf), "%u", minor); 570 ddi_remove_minor_node(zfs_dip, nmbuf); 571 572 avl_destroy(&zv->zv_znode.z_range_avl); 573 mutex_destroy(&zv->zv_znode.z_range_lock); 574 575 kmem_free(zv, sizeof (zvol_state_t)); 576 577 ddi_soft_state_free(zfsdev_state, minor); 578 579 zvol_minors--; 580 return (0); 581 } 582 583 int 584 zvol_remove_minor(const char *name) 585 { 586 zvol_state_t *zv; 587 int rc; 588 589 mutex_enter(&zfsdev_state_lock); 590 if ((zv = zvol_minor_lookup(name)) == NULL) { 591 mutex_exit(&zfsdev_state_lock); 592 return (ENXIO); 593 } 594 rc = zvol_remove_zv(zv); 595 mutex_exit(&zfsdev_state_lock); 596 return (rc); 597 } 598 599 int 600 zvol_first_open(zvol_state_t *zv) 601 { 602 objset_t *os; 603 uint64_t volsize; 604 int error; 605 uint64_t readonly; 606 607 /* lie and say we're read-only */ 608 error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, B_TRUE, 609 zvol_tag, &os); 610 if (error) 611 return (error); 612 613 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize); 614 if (error) { 615 ASSERT(error == 0); 616 dmu_objset_disown(os, zvol_tag); 617 return (error); 618 } 619 zv->zv_objset = os; 620 error = dmu_bonus_hold(os, ZVOL_OBJ, zvol_tag, &zv->zv_dbuf); 621 if (error) { 622 dmu_objset_disown(os, zvol_tag); 623 return (error); 624 } 625 zv->zv_volsize = volsize; 626 zv->zv_zilog = zil_open(os, zvol_get_data); 627 zvol_size_changed(zv->zv_volsize, ddi_driver_major(zfs_dip), 628 zv->zv_minor); 629 630 VERIFY(dsl_prop_get_integer(zv->zv_name, "readonly", &readonly, 631 NULL) == 0); 632 if (readonly || dmu_objset_is_snapshot(os) || 633 !spa_writeable(dmu_objset_spa(os))) 634 zv->zv_flags |= ZVOL_RDONLY; 635 else 636 zv->zv_flags &= ~ZVOL_RDONLY; 637 return (error); 638 } 639 640 void 641 zvol_last_close(zvol_state_t *zv) 642 { 643 zil_close(zv->zv_zilog); 644 zv->zv_zilog = NULL; 645 646 dmu_buf_rele(zv->zv_dbuf, zvol_tag); 647 zv->zv_dbuf = NULL; 648 649 /* 650 * Evict cached data 651 */ 652 if (dsl_dataset_is_dirty(dmu_objset_ds(zv->zv_objset)) && 653 !(zv->zv_flags & ZVOL_RDONLY)) 654 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 655 (void) dmu_objset_evict_dbufs(zv->zv_objset); 656 657 dmu_objset_disown(zv->zv_objset, zvol_tag); 658 zv->zv_objset = NULL; 659 } 660 661 int 662 zvol_prealloc(zvol_state_t *zv) 663 { 664 objset_t *os = zv->zv_objset; 665 dmu_tx_t *tx; 666 uint64_t refd, avail, usedobjs, availobjs; 667 uint64_t resid = zv->zv_volsize; 668 uint64_t off = 0; 669 670 /* Check the space usage before attempting to allocate the space */ 671 dmu_objset_space(os, &refd, &avail, &usedobjs, &availobjs); 672 if (avail < zv->zv_volsize) 673 return (ENOSPC); 674 675 /* Free old extents if they exist */ 676 zvol_free_extents(zv); 677 678 while (resid != 0) { 679 int error; 680 uint64_t bytes = MIN(resid, SPA_MAXBLOCKSIZE); 681 682 tx = dmu_tx_create(os); 683 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes); 684 error = dmu_tx_assign(tx, TXG_WAIT); 685 if (error) { 686 dmu_tx_abort(tx); 687 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, off); 688 return (error); 689 } 690 dmu_prealloc(os, ZVOL_OBJ, off, bytes, tx); 691 dmu_tx_commit(tx); 692 off += bytes; 693 resid -= bytes; 694 } 695 txg_wait_synced(dmu_objset_pool(os), 0); 696 697 return (0); 698 } 699 700 int 701 zvol_update_volsize(objset_t *os, uint64_t volsize) 702 { 703 dmu_tx_t *tx; 704 int error; 705 706 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 707 708 tx = dmu_tx_create(os); 709 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 710 error = dmu_tx_assign(tx, TXG_WAIT); 711 if (error) { 712 dmu_tx_abort(tx); 713 return (error); 714 } 715 716 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, 717 &volsize, tx); 718 dmu_tx_commit(tx); 719 720 if (error == 0) 721 error = dmu_free_long_range(os, 722 ZVOL_OBJ, volsize, DMU_OBJECT_END); 723 return (error); 724 } 725 726 void 727 zvol_remove_minors(const char *name) 728 { 729 zvol_state_t *zv; 730 char *namebuf; 731 minor_t minor; 732 733 namebuf = kmem_zalloc(strlen(name) + 2, KM_SLEEP); 734 (void) strncpy(namebuf, name, strlen(name)); 735 (void) strcat(namebuf, "/"); 736 mutex_enter(&zfsdev_state_lock); 737 for (minor = 1; minor <= ZFSDEV_MAX_MINOR; minor++) { 738 739 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 740 if (zv == NULL) 741 continue; 742 if (strncmp(namebuf, zv->zv_name, strlen(namebuf)) == 0) 743 (void) zvol_remove_zv(zv); 744 } 745 kmem_free(namebuf, strlen(name) + 2); 746 747 mutex_exit(&zfsdev_state_lock); 748 } 749 750 int 751 zvol_set_volsize(const char *name, major_t maj, uint64_t volsize) 752 { 753 zvol_state_t *zv = NULL; 754 objset_t *os; 755 int error; 756 dmu_object_info_t doi; 757 uint64_t old_volsize = 0ULL; 758 uint64_t readonly; 759 760 mutex_enter(&zfsdev_state_lock); 761 zv = zvol_minor_lookup(name); 762 if ((error = dmu_objset_hold(name, FTAG, &os)) != 0) { 763 mutex_exit(&zfsdev_state_lock); 764 return (error); 765 } 766 767 if ((error = dmu_object_info(os, ZVOL_OBJ, &doi)) != 0 || 768 (error = zvol_check_volsize(volsize, 769 doi.doi_data_block_size)) != 0) 770 goto out; 771 772 VERIFY(dsl_prop_get_integer(name, "readonly", &readonly, 773 NULL) == 0); 774 if (readonly) { 775 error = EROFS; 776 goto out; 777 } 778 779 error = zvol_update_volsize(os, volsize); 780 /* 781 * Reinitialize the dump area to the new size. If we 782 * failed to resize the dump area then restore it back to 783 * its original size. 784 */ 785 if (zv && error == 0) { 786 if (zv->zv_flags & ZVOL_DUMPIFIED) { 787 old_volsize = zv->zv_volsize; 788 zv->zv_volsize = volsize; 789 if ((error = zvol_dumpify(zv)) != 0 || 790 (error = dumpvp_resize()) != 0) { 791 (void) zvol_update_volsize(os, old_volsize); 792 zv->zv_volsize = old_volsize; 793 error = zvol_dumpify(zv); 794 } 795 } 796 if (error == 0) { 797 zv->zv_volsize = volsize; 798 zvol_size_changed(volsize, maj, zv->zv_minor); 799 } 800 } 801 802 /* 803 * Generate a LUN expansion event. 804 */ 805 if (zv && error == 0) { 806 sysevent_id_t eid; 807 nvlist_t *attr; 808 char *physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 809 810 (void) snprintf(physpath, MAXPATHLEN, "%s%u", ZVOL_PSEUDO_DEV, 811 zv->zv_minor); 812 813 VERIFY(nvlist_alloc(&attr, NV_UNIQUE_NAME, KM_SLEEP) == 0); 814 VERIFY(nvlist_add_string(attr, DEV_PHYS_PATH, physpath) == 0); 815 816 (void) ddi_log_sysevent(zfs_dip, SUNW_VENDOR, EC_DEV_STATUS, 817 ESC_DEV_DLE, attr, &eid, DDI_SLEEP); 818 819 nvlist_free(attr); 820 kmem_free(physpath, MAXPATHLEN); 821 } 822 823 out: 824 dmu_objset_rele(os, FTAG); 825 826 mutex_exit(&zfsdev_state_lock); 827 828 return (error); 829 } 830 831 /*ARGSUSED*/ 832 int 833 zvol_open(dev_t *devp, int flag, int otyp, cred_t *cr) 834 { 835 zvol_state_t *zv; 836 int err = 0; 837 838 mutex_enter(&zfsdev_state_lock); 839 840 zv = zfsdev_get_soft_state(getminor(*devp), ZSST_ZVOL); 841 if (zv == NULL) { 842 mutex_exit(&zfsdev_state_lock); 843 return (ENXIO); 844 } 845 846 if (zv->zv_total_opens == 0) 847 err = zvol_first_open(zv); 848 if (err) { 849 mutex_exit(&zfsdev_state_lock); 850 return (err); 851 } 852 if ((flag & FWRITE) && (zv->zv_flags & ZVOL_RDONLY)) { 853 err = EROFS; 854 goto out; 855 } 856 if (zv->zv_flags & ZVOL_EXCL) { 857 err = EBUSY; 858 goto out; 859 } 860 if (flag & FEXCL) { 861 if (zv->zv_total_opens != 0) { 862 err = EBUSY; 863 goto out; 864 } 865 zv->zv_flags |= ZVOL_EXCL; 866 } 867 868 if (zv->zv_open_count[otyp] == 0 || otyp == OTYP_LYR) { 869 zv->zv_open_count[otyp]++; 870 zv->zv_total_opens++; 871 } 872 mutex_exit(&zfsdev_state_lock); 873 874 return (err); 875 out: 876 if (zv->zv_total_opens == 0) 877 zvol_last_close(zv); 878 mutex_exit(&zfsdev_state_lock); 879 return (err); 880 } 881 882 /*ARGSUSED*/ 883 int 884 zvol_close(dev_t dev, int flag, int otyp, cred_t *cr) 885 { 886 minor_t minor = getminor(dev); 887 zvol_state_t *zv; 888 int error = 0; 889 890 mutex_enter(&zfsdev_state_lock); 891 892 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 893 if (zv == NULL) { 894 mutex_exit(&zfsdev_state_lock); 895 return (ENXIO); 896 } 897 898 if (zv->zv_flags & ZVOL_EXCL) { 899 ASSERT(zv->zv_total_opens == 1); 900 zv->zv_flags &= ~ZVOL_EXCL; 901 } 902 903 /* 904 * If the open count is zero, this is a spurious close. 905 * That indicates a bug in the kernel / DDI framework. 906 */ 907 ASSERT(zv->zv_open_count[otyp] != 0); 908 ASSERT(zv->zv_total_opens != 0); 909 910 /* 911 * You may get multiple opens, but only one close. 912 */ 913 zv->zv_open_count[otyp]--; 914 zv->zv_total_opens--; 915 916 if (zv->zv_total_opens == 0) 917 zvol_last_close(zv); 918 919 mutex_exit(&zfsdev_state_lock); 920 return (error); 921 } 922 923 static void 924 zvol_get_done(zgd_t *zgd, int error) 925 { 926 if (zgd->zgd_db) 927 dmu_buf_rele(zgd->zgd_db, zgd); 928 929 zfs_range_unlock(zgd->zgd_rl); 930 931 if (error == 0 && zgd->zgd_bp) 932 zil_add_block(zgd->zgd_zilog, zgd->zgd_bp); 933 934 kmem_free(zgd, sizeof (zgd_t)); 935 } 936 937 /* 938 * Get data to generate a TX_WRITE intent log record. 939 */ 940 static int 941 zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio) 942 { 943 zvol_state_t *zv = arg; 944 objset_t *os = zv->zv_objset; 945 uint64_t object = ZVOL_OBJ; 946 uint64_t offset = lr->lr_offset; 947 uint64_t size = lr->lr_length; /* length of user data */ 948 blkptr_t *bp = &lr->lr_blkptr; 949 dmu_buf_t *db; 950 zgd_t *zgd; 951 int error; 952 953 ASSERT(zio != NULL); 954 ASSERT(size != 0); 955 956 zgd = kmem_zalloc(sizeof (zgd_t), KM_SLEEP); 957 zgd->zgd_zilog = zv->zv_zilog; 958 zgd->zgd_rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER); 959 960 /* 961 * Write records come in two flavors: immediate and indirect. 962 * For small writes it's cheaper to store the data with the 963 * log record (immediate); for large writes it's cheaper to 964 * sync the data and get a pointer to it (indirect) so that 965 * we don't have to write the data twice. 966 */ 967 if (buf != NULL) { /* immediate write */ 968 error = dmu_read(os, object, offset, size, buf, 969 DMU_READ_NO_PREFETCH); 970 } else { 971 size = zv->zv_volblocksize; 972 offset = P2ALIGN(offset, size); 973 error = dmu_buf_hold(os, object, offset, zgd, &db, 974 DMU_READ_NO_PREFETCH); 975 if (error == 0) { 976 blkptr_t *obp = dmu_buf_get_blkptr(db); 977 if (obp) { 978 ASSERT(BP_IS_HOLE(bp)); 979 *bp = *obp; 980 } 981 982 zgd->zgd_db = db; 983 zgd->zgd_bp = bp; 984 985 ASSERT(db->db_offset == offset); 986 ASSERT(db->db_size == size); 987 988 error = dmu_sync(zio, lr->lr_common.lrc_txg, 989 zvol_get_done, zgd); 990 991 if (error == 0) 992 return (0); 993 } 994 } 995 996 zvol_get_done(zgd, error); 997 998 return (error); 999 } 1000 1001 /* 1002 * zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions. 1003 * 1004 * We store data in the log buffers if it's small enough. 1005 * Otherwise we will later flush the data out via dmu_sync(). 1006 */ 1007 ssize_t zvol_immediate_write_sz = 32768; 1008 1009 static void 1010 zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, offset_t off, ssize_t resid, 1011 boolean_t sync) 1012 { 1013 uint32_t blocksize = zv->zv_volblocksize; 1014 zilog_t *zilog = zv->zv_zilog; 1015 boolean_t slogging; 1016 ssize_t immediate_write_sz; 1017 1018 if (zil_replaying(zilog, tx)) 1019 return; 1020 1021 immediate_write_sz = (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT) 1022 ? 0 : zvol_immediate_write_sz; 1023 1024 slogging = spa_has_slogs(zilog->zl_spa) && 1025 (zilog->zl_logbias == ZFS_LOGBIAS_LATENCY); 1026 1027 while (resid) { 1028 itx_t *itx; 1029 lr_write_t *lr; 1030 ssize_t len; 1031 itx_wr_state_t write_state; 1032 1033 /* 1034 * Unlike zfs_log_write() we can be called with 1035 * upto DMU_MAX_ACCESS/2 (5MB) writes. 1036 */ 1037 if (blocksize > immediate_write_sz && !slogging && 1038 resid >= blocksize && off % blocksize == 0) { 1039 write_state = WR_INDIRECT; /* uses dmu_sync */ 1040 len = blocksize; 1041 } else if (sync) { 1042 write_state = WR_COPIED; 1043 len = MIN(ZIL_MAX_LOG_DATA, resid); 1044 } else { 1045 write_state = WR_NEED_COPY; 1046 len = MIN(ZIL_MAX_LOG_DATA, resid); 1047 } 1048 1049 itx = zil_itx_create(TX_WRITE, sizeof (*lr) + 1050 (write_state == WR_COPIED ? len : 0)); 1051 lr = (lr_write_t *)&itx->itx_lr; 1052 if (write_state == WR_COPIED && dmu_read(zv->zv_objset, 1053 ZVOL_OBJ, off, len, lr + 1, DMU_READ_NO_PREFETCH) != 0) { 1054 zil_itx_destroy(itx); 1055 itx = zil_itx_create(TX_WRITE, sizeof (*lr)); 1056 lr = (lr_write_t *)&itx->itx_lr; 1057 write_state = WR_NEED_COPY; 1058 } 1059 1060 itx->itx_wr_state = write_state; 1061 if (write_state == WR_NEED_COPY) 1062 itx->itx_sod += len; 1063 lr->lr_foid = ZVOL_OBJ; 1064 lr->lr_offset = off; 1065 lr->lr_length = len; 1066 lr->lr_blkoff = 0; 1067 BP_ZERO(&lr->lr_blkptr); 1068 1069 itx->itx_private = zv; 1070 itx->itx_sync = sync; 1071 1072 zil_itx_assign(zilog, itx, tx); 1073 1074 off += len; 1075 resid -= len; 1076 } 1077 } 1078 1079 static int 1080 zvol_dumpio_vdev(vdev_t *vd, void *addr, uint64_t offset, uint64_t size, 1081 boolean_t doread, boolean_t isdump) 1082 { 1083 vdev_disk_t *dvd; 1084 int c; 1085 int numerrors = 0; 1086 1087 for (c = 0; c < vd->vdev_children; c++) { 1088 ASSERT(vd->vdev_ops == &vdev_mirror_ops || 1089 vd->vdev_ops == &vdev_replacing_ops || 1090 vd->vdev_ops == &vdev_spare_ops); 1091 int err = zvol_dumpio_vdev(vd->vdev_child[c], 1092 addr, offset, size, doread, isdump); 1093 if (err != 0) { 1094 numerrors++; 1095 } else if (doread) { 1096 break; 1097 } 1098 } 1099 1100 if (!vd->vdev_ops->vdev_op_leaf) 1101 return (numerrors < vd->vdev_children ? 0 : EIO); 1102 1103 if (doread && !vdev_readable(vd)) 1104 return (EIO); 1105 else if (!doread && !vdev_writeable(vd)) 1106 return (EIO); 1107 1108 dvd = vd->vdev_tsd; 1109 ASSERT3P(dvd, !=, NULL); 1110 offset += VDEV_LABEL_START_SIZE; 1111 1112 if (ddi_in_panic() || isdump) { 1113 ASSERT(!doread); 1114 if (doread) 1115 return (EIO); 1116 return (ldi_dump(dvd->vd_lh, addr, lbtodb(offset), 1117 lbtodb(size))); 1118 } else { 1119 return (vdev_disk_physio(dvd->vd_lh, addr, size, offset, 1120 doread ? B_READ : B_WRITE)); 1121 } 1122 } 1123 1124 static int 1125 zvol_dumpio(zvol_state_t *zv, void *addr, uint64_t offset, uint64_t size, 1126 boolean_t doread, boolean_t isdump) 1127 { 1128 vdev_t *vd; 1129 int error; 1130 zvol_extent_t *ze; 1131 spa_t *spa = dmu_objset_spa(zv->zv_objset); 1132 1133 /* Must be sector aligned, and not stradle a block boundary. */ 1134 if (P2PHASE(offset, DEV_BSIZE) || P2PHASE(size, DEV_BSIZE) || 1135 P2BOUNDARY(offset, size, zv->zv_volblocksize)) { 1136 return (EINVAL); 1137 } 1138 ASSERT(size <= zv->zv_volblocksize); 1139 1140 /* Locate the extent this belongs to */ 1141 ze = list_head(&zv->zv_extents); 1142 while (offset >= ze->ze_nblks * zv->zv_volblocksize) { 1143 offset -= ze->ze_nblks * zv->zv_volblocksize; 1144 ze = list_next(&zv->zv_extents, ze); 1145 } 1146 1147 if (!ddi_in_panic()) 1148 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER); 1149 1150 vd = vdev_lookup_top(spa, DVA_GET_VDEV(&ze->ze_dva)); 1151 offset += DVA_GET_OFFSET(&ze->ze_dva); 1152 error = zvol_dumpio_vdev(vd, addr, offset, size, doread, isdump); 1153 1154 if (!ddi_in_panic()) 1155 spa_config_exit(spa, SCL_STATE, FTAG); 1156 1157 return (error); 1158 } 1159 1160 int 1161 zvol_strategy(buf_t *bp) 1162 { 1163 zfs_soft_state_t *zs = NULL; 1164 zvol_state_t *zv; 1165 uint64_t off, volsize; 1166 size_t resid; 1167 char *addr; 1168 objset_t *os; 1169 rl_t *rl; 1170 int error = 0; 1171 boolean_t doread = bp->b_flags & B_READ; 1172 boolean_t is_dump; 1173 boolean_t sync; 1174 1175 if (getminor(bp->b_edev) == 0) { 1176 error = EINVAL; 1177 } else { 1178 zs = ddi_get_soft_state(zfsdev_state, getminor(bp->b_edev)); 1179 if (zs == NULL) 1180 error = ENXIO; 1181 else if (zs->zss_type != ZSST_ZVOL) 1182 error = EINVAL; 1183 } 1184 1185 if (error) { 1186 bioerror(bp, error); 1187 biodone(bp); 1188 return (0); 1189 } 1190 1191 zv = zs->zss_data; 1192 1193 if (!(bp->b_flags & B_READ) && (zv->zv_flags & ZVOL_RDONLY)) { 1194 bioerror(bp, EROFS); 1195 biodone(bp); 1196 return (0); 1197 } 1198 1199 off = ldbtob(bp->b_blkno); 1200 volsize = zv->zv_volsize; 1201 1202 os = zv->zv_objset; 1203 ASSERT(os != NULL); 1204 1205 bp_mapin(bp); 1206 addr = bp->b_un.b_addr; 1207 resid = bp->b_bcount; 1208 1209 if (resid > 0 && (off < 0 || off >= volsize)) { 1210 bioerror(bp, EIO); 1211 biodone(bp); 1212 return (0); 1213 } 1214 1215 is_dump = zv->zv_flags & ZVOL_DUMPIFIED; 1216 sync = ((!(bp->b_flags & B_ASYNC) && 1217 !(zv->zv_flags & ZVOL_WCE)) || 1218 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)) && 1219 !doread && !is_dump; 1220 1221 /* 1222 * There must be no buffer changes when doing a dmu_sync() because 1223 * we can't change the data whilst calculating the checksum. 1224 */ 1225 rl = zfs_range_lock(&zv->zv_znode, off, resid, 1226 doread ? RL_READER : RL_WRITER); 1227 1228 while (resid != 0 && off < volsize) { 1229 size_t size = MIN(resid, zvol_maxphys); 1230 if (is_dump) { 1231 size = MIN(size, P2END(off, zv->zv_volblocksize) - off); 1232 error = zvol_dumpio(zv, addr, off, size, 1233 doread, B_FALSE); 1234 } else if (doread) { 1235 error = dmu_read(os, ZVOL_OBJ, off, size, addr, 1236 DMU_READ_PREFETCH); 1237 } else { 1238 dmu_tx_t *tx = dmu_tx_create(os); 1239 dmu_tx_hold_write(tx, ZVOL_OBJ, off, size); 1240 error = dmu_tx_assign(tx, TXG_WAIT); 1241 if (error) { 1242 dmu_tx_abort(tx); 1243 } else { 1244 dmu_write(os, ZVOL_OBJ, off, size, addr, tx); 1245 zvol_log_write(zv, tx, off, size, sync); 1246 dmu_tx_commit(tx); 1247 } 1248 } 1249 if (error) { 1250 /* convert checksum errors into IO errors */ 1251 if (error == ECKSUM) 1252 error = EIO; 1253 break; 1254 } 1255 off += size; 1256 addr += size; 1257 resid -= size; 1258 } 1259 zfs_range_unlock(rl); 1260 1261 if ((bp->b_resid = resid) == bp->b_bcount) 1262 bioerror(bp, off > volsize ? EINVAL : error); 1263 1264 if (sync) 1265 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1266 biodone(bp); 1267 1268 return (0); 1269 } 1270 1271 /* 1272 * Set the buffer count to the zvol maximum transfer. 1273 * Using our own routine instead of the default minphys() 1274 * means that for larger writes we write bigger buffers on X86 1275 * (128K instead of 56K) and flush the disk write cache less often 1276 * (every zvol_maxphys - currently 1MB) instead of minphys (currently 1277 * 56K on X86 and 128K on sparc). 1278 */ 1279 void 1280 zvol_minphys(struct buf *bp) 1281 { 1282 if (bp->b_bcount > zvol_maxphys) 1283 bp->b_bcount = zvol_maxphys; 1284 } 1285 1286 int 1287 zvol_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblocks) 1288 { 1289 minor_t minor = getminor(dev); 1290 zvol_state_t *zv; 1291 int error = 0; 1292 uint64_t size; 1293 uint64_t boff; 1294 uint64_t resid; 1295 1296 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1297 if (zv == NULL) 1298 return (ENXIO); 1299 1300 boff = ldbtob(blkno); 1301 resid = ldbtob(nblocks); 1302 1303 VERIFY3U(boff + resid, <=, zv->zv_volsize); 1304 1305 while (resid) { 1306 size = MIN(resid, P2END(boff, zv->zv_volblocksize) - boff); 1307 error = zvol_dumpio(zv, addr, boff, size, B_FALSE, B_TRUE); 1308 if (error) 1309 break; 1310 boff += size; 1311 addr += size; 1312 resid -= size; 1313 } 1314 1315 return (error); 1316 } 1317 1318 /*ARGSUSED*/ 1319 int 1320 zvol_read(dev_t dev, uio_t *uio, cred_t *cr) 1321 { 1322 minor_t minor = getminor(dev); 1323 zvol_state_t *zv; 1324 uint64_t volsize; 1325 rl_t *rl; 1326 int error = 0; 1327 1328 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1329 if (zv == NULL) 1330 return (ENXIO); 1331 1332 volsize = zv->zv_volsize; 1333 if (uio->uio_resid > 0 && 1334 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize)) 1335 return (EIO); 1336 1337 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1338 error = physio(zvol_strategy, NULL, dev, B_READ, 1339 zvol_minphys, uio); 1340 return (error); 1341 } 1342 1343 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid, 1344 RL_READER); 1345 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1346 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1347 1348 /* don't read past the end */ 1349 if (bytes > volsize - uio->uio_loffset) 1350 bytes = volsize - uio->uio_loffset; 1351 1352 error = dmu_read_uio(zv->zv_objset, ZVOL_OBJ, uio, bytes); 1353 if (error) { 1354 /* convert checksum errors into IO errors */ 1355 if (error == ECKSUM) 1356 error = EIO; 1357 break; 1358 } 1359 } 1360 zfs_range_unlock(rl); 1361 return (error); 1362 } 1363 1364 /*ARGSUSED*/ 1365 int 1366 zvol_write(dev_t dev, uio_t *uio, cred_t *cr) 1367 { 1368 minor_t minor = getminor(dev); 1369 zvol_state_t *zv; 1370 uint64_t volsize; 1371 rl_t *rl; 1372 int error = 0; 1373 boolean_t sync; 1374 1375 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1376 if (zv == NULL) 1377 return (ENXIO); 1378 1379 volsize = zv->zv_volsize; 1380 if (uio->uio_resid > 0 && 1381 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize)) 1382 return (EIO); 1383 1384 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1385 error = physio(zvol_strategy, NULL, dev, B_WRITE, 1386 zvol_minphys, uio); 1387 return (error); 1388 } 1389 1390 sync = !(zv->zv_flags & ZVOL_WCE) || 1391 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS); 1392 1393 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid, 1394 RL_WRITER); 1395 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1396 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1397 uint64_t off = uio->uio_loffset; 1398 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset); 1399 1400 if (bytes > volsize - off) /* don't write past the end */ 1401 bytes = volsize - off; 1402 1403 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes); 1404 error = dmu_tx_assign(tx, TXG_WAIT); 1405 if (error) { 1406 dmu_tx_abort(tx); 1407 break; 1408 } 1409 error = dmu_write_uio_dbuf(zv->zv_dbuf, uio, bytes, tx); 1410 if (error == 0) 1411 zvol_log_write(zv, tx, off, bytes, sync); 1412 dmu_tx_commit(tx); 1413 1414 if (error) 1415 break; 1416 } 1417 zfs_range_unlock(rl); 1418 if (sync) 1419 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1420 return (error); 1421 } 1422 1423 int 1424 zvol_getefi(void *arg, int flag, uint64_t vs, uint8_t bs) 1425 { 1426 struct uuid uuid = EFI_RESERVED; 1427 efi_gpe_t gpe = { 0 }; 1428 uint32_t crc; 1429 dk_efi_t efi; 1430 int length; 1431 char *ptr; 1432 1433 if (ddi_copyin(arg, &efi, sizeof (dk_efi_t), flag)) 1434 return (EFAULT); 1435 ptr = (char *)(uintptr_t)efi.dki_data_64; 1436 length = efi.dki_length; 1437 /* 1438 * Some clients may attempt to request a PMBR for the 1439 * zvol. Currently this interface will return EINVAL to 1440 * such requests. These requests could be supported by 1441 * adding a check for lba == 0 and consing up an appropriate 1442 * PMBR. 1443 */ 1444 if (efi.dki_lba < 1 || efi.dki_lba > 2 || length <= 0) 1445 return (EINVAL); 1446 1447 gpe.efi_gpe_StartingLBA = LE_64(34ULL); 1448 gpe.efi_gpe_EndingLBA = LE_64((vs >> bs) - 1); 1449 UUID_LE_CONVERT(gpe.efi_gpe_PartitionTypeGUID, uuid); 1450 1451 if (efi.dki_lba == 1) { 1452 efi_gpt_t gpt = { 0 }; 1453 1454 gpt.efi_gpt_Signature = LE_64(EFI_SIGNATURE); 1455 gpt.efi_gpt_Revision = LE_32(EFI_VERSION_CURRENT); 1456 gpt.efi_gpt_HeaderSize = LE_32(sizeof (gpt)); 1457 gpt.efi_gpt_MyLBA = LE_64(1ULL); 1458 gpt.efi_gpt_FirstUsableLBA = LE_64(34ULL); 1459 gpt.efi_gpt_LastUsableLBA = LE_64((vs >> bs) - 1); 1460 gpt.efi_gpt_PartitionEntryLBA = LE_64(2ULL); 1461 gpt.efi_gpt_NumberOfPartitionEntries = LE_32(1); 1462 gpt.efi_gpt_SizeOfPartitionEntry = 1463 LE_32(sizeof (efi_gpe_t)); 1464 CRC32(crc, &gpe, sizeof (gpe), -1U, crc32_table); 1465 gpt.efi_gpt_PartitionEntryArrayCRC32 = LE_32(~crc); 1466 CRC32(crc, &gpt, sizeof (gpt), -1U, crc32_table); 1467 gpt.efi_gpt_HeaderCRC32 = LE_32(~crc); 1468 if (ddi_copyout(&gpt, ptr, MIN(sizeof (gpt), length), 1469 flag)) 1470 return (EFAULT); 1471 ptr += sizeof (gpt); 1472 length -= sizeof (gpt); 1473 } 1474 if (length > 0 && ddi_copyout(&gpe, ptr, MIN(sizeof (gpe), 1475 length), flag)) 1476 return (EFAULT); 1477 return (0); 1478 } 1479 1480 /* 1481 * BEGIN entry points to allow external callers access to the volume. 1482 */ 1483 /* 1484 * Return the volume parameters needed for access from an external caller. 1485 * These values are invariant as long as the volume is held open. 1486 */ 1487 int 1488 zvol_get_volume_params(minor_t minor, uint64_t *blksize, 1489 uint64_t *max_xfer_len, void **minor_hdl, void **objset_hdl, void **zil_hdl, 1490 void **rl_hdl, void **bonus_hdl) 1491 { 1492 zvol_state_t *zv; 1493 1494 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1495 if (zv == NULL) 1496 return (ENXIO); 1497 if (zv->zv_flags & ZVOL_DUMPIFIED) 1498 return (ENXIO); 1499 1500 ASSERT(blksize && max_xfer_len && minor_hdl && 1501 objset_hdl && zil_hdl && rl_hdl && bonus_hdl); 1502 1503 *blksize = zv->zv_volblocksize; 1504 *max_xfer_len = (uint64_t)zvol_maxphys; 1505 *minor_hdl = zv; 1506 *objset_hdl = zv->zv_objset; 1507 *zil_hdl = zv->zv_zilog; 1508 *rl_hdl = &zv->zv_znode; 1509 *bonus_hdl = zv->zv_dbuf; 1510 return (0); 1511 } 1512 1513 /* 1514 * Return the current volume size to an external caller. 1515 * The size can change while the volume is open. 1516 */ 1517 uint64_t 1518 zvol_get_volume_size(void *minor_hdl) 1519 { 1520 zvol_state_t *zv = minor_hdl; 1521 1522 return (zv->zv_volsize); 1523 } 1524 1525 /* 1526 * Return the current WCE setting to an external caller. 1527 * The WCE setting can change while the volume is open. 1528 */ 1529 int 1530 zvol_get_volume_wce(void *minor_hdl) 1531 { 1532 zvol_state_t *zv = minor_hdl; 1533 1534 return ((zv->zv_flags & ZVOL_WCE) ? 1 : 0); 1535 } 1536 1537 /* 1538 * Entry point for external callers to zvol_log_write 1539 */ 1540 void 1541 zvol_log_write_minor(void *minor_hdl, dmu_tx_t *tx, offset_t off, ssize_t resid, 1542 boolean_t sync) 1543 { 1544 zvol_state_t *zv = minor_hdl; 1545 1546 zvol_log_write(zv, tx, off, resid, sync); 1547 } 1548 /* 1549 * END entry points to allow external callers access to the volume. 1550 */ 1551 1552 /* 1553 * Log a DKIOCFREE/free-long-range to the ZIL with TX_TRUNCATE. 1554 */ 1555 static void 1556 zvol_log_truncate(zvol_state_t *zv, dmu_tx_t *tx, uint64_t off, uint64_t len, 1557 boolean_t sync) 1558 { 1559 itx_t *itx; 1560 lr_truncate_t *lr; 1561 zilog_t *zilog = zv->zv_zilog; 1562 1563 if (zil_replaying(zilog, tx)) 1564 return; 1565 1566 itx = zil_itx_create(TX_TRUNCATE, sizeof (*lr)); 1567 lr = (lr_truncate_t *)&itx->itx_lr; 1568 lr->lr_foid = ZVOL_OBJ; 1569 lr->lr_offset = off; 1570 lr->lr_length = len; 1571 1572 itx->itx_sync = sync; 1573 zil_itx_assign(zilog, itx, tx); 1574 } 1575 1576 /* 1577 * Dirtbag ioctls to support mkfs(1M) for UFS filesystems. See dkio(7I). 1578 * Also a dirtbag dkio ioctl for unmap/free-block functionality. 1579 */ 1580 /*ARGSUSED*/ 1581 int 1582 zvol_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp) 1583 { 1584 zvol_state_t *zv; 1585 struct dk_cinfo dki; 1586 struct dk_minfo dkm; 1587 struct dk_callback *dkc; 1588 int error = 0; 1589 rl_t *rl; 1590 1591 mutex_enter(&zfsdev_state_lock); 1592 1593 zv = zfsdev_get_soft_state(getminor(dev), ZSST_ZVOL); 1594 1595 if (zv == NULL) { 1596 mutex_exit(&zfsdev_state_lock); 1597 return (ENXIO); 1598 } 1599 ASSERT(zv->zv_total_opens > 0); 1600 1601 switch (cmd) { 1602 1603 case DKIOCINFO: 1604 bzero(&dki, sizeof (dki)); 1605 (void) strcpy(dki.dki_cname, "zvol"); 1606 (void) strcpy(dki.dki_dname, "zvol"); 1607 dki.dki_ctype = DKC_UNKNOWN; 1608 dki.dki_unit = getminor(dev); 1609 dki.dki_maxtransfer = 1 << (SPA_MAXBLOCKSHIFT - zv->zv_min_bs); 1610 mutex_exit(&zfsdev_state_lock); 1611 if (ddi_copyout(&dki, (void *)arg, sizeof (dki), flag)) 1612 error = EFAULT; 1613 return (error); 1614 1615 case DKIOCGMEDIAINFO: 1616 bzero(&dkm, sizeof (dkm)); 1617 dkm.dki_lbsize = 1U << zv->zv_min_bs; 1618 dkm.dki_capacity = zv->zv_volsize >> zv->zv_min_bs; 1619 dkm.dki_media_type = DK_UNKNOWN; 1620 mutex_exit(&zfsdev_state_lock); 1621 if (ddi_copyout(&dkm, (void *)arg, sizeof (dkm), flag)) 1622 error = EFAULT; 1623 return (error); 1624 1625 case DKIOCGETEFI: 1626 { 1627 uint64_t vs = zv->zv_volsize; 1628 uint8_t bs = zv->zv_min_bs; 1629 1630 mutex_exit(&zfsdev_state_lock); 1631 error = zvol_getefi((void *)arg, flag, vs, bs); 1632 return (error); 1633 } 1634 1635 case DKIOCFLUSHWRITECACHE: 1636 dkc = (struct dk_callback *)arg; 1637 mutex_exit(&zfsdev_state_lock); 1638 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1639 if ((flag & FKIOCTL) && dkc != NULL && dkc->dkc_callback) { 1640 (*dkc->dkc_callback)(dkc->dkc_cookie, error); 1641 error = 0; 1642 } 1643 return (error); 1644 1645 case DKIOCGETWCE: 1646 { 1647 int wce = (zv->zv_flags & ZVOL_WCE) ? 1 : 0; 1648 if (ddi_copyout(&wce, (void *)arg, sizeof (int), 1649 flag)) 1650 error = EFAULT; 1651 break; 1652 } 1653 case DKIOCSETWCE: 1654 { 1655 int wce; 1656 if (ddi_copyin((void *)arg, &wce, sizeof (int), 1657 flag)) { 1658 error = EFAULT; 1659 break; 1660 } 1661 if (wce) { 1662 zv->zv_flags |= ZVOL_WCE; 1663 mutex_exit(&zfsdev_state_lock); 1664 } else { 1665 zv->zv_flags &= ~ZVOL_WCE; 1666 mutex_exit(&zfsdev_state_lock); 1667 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1668 } 1669 return (0); 1670 } 1671 1672 case DKIOCGGEOM: 1673 case DKIOCGVTOC: 1674 /* 1675 * commands using these (like prtvtoc) expect ENOTSUP 1676 * since we're emulating an EFI label 1677 */ 1678 error = ENOTSUP; 1679 break; 1680 1681 case DKIOCDUMPINIT: 1682 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize, 1683 RL_WRITER); 1684 error = zvol_dumpify(zv); 1685 zfs_range_unlock(rl); 1686 break; 1687 1688 case DKIOCDUMPFINI: 1689 if (!(zv->zv_flags & ZVOL_DUMPIFIED)) 1690 break; 1691 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize, 1692 RL_WRITER); 1693 error = zvol_dump_fini(zv); 1694 zfs_range_unlock(rl); 1695 break; 1696 1697 case DKIOCFREE: 1698 { 1699 dkioc_free_t df; 1700 dmu_tx_t *tx; 1701 1702 if (ddi_copyin((void *)arg, &df, sizeof (df), flag)) { 1703 error = EFAULT; 1704 break; 1705 } 1706 1707 /* 1708 * Apply Postel's Law to length-checking. If they overshoot, 1709 * just blank out until the end, if there's a need to blank 1710 * out anything. 1711 */ 1712 if (df.df_start >= zv->zv_volsize) 1713 break; /* No need to do anything... */ 1714 if (df.df_start + df.df_length > zv->zv_volsize) 1715 df.df_length = DMU_OBJECT_END; 1716 1717 rl = zfs_range_lock(&zv->zv_znode, df.df_start, df.df_length, 1718 RL_WRITER); 1719 tx = dmu_tx_create(zv->zv_objset); 1720 error = dmu_tx_assign(tx, TXG_WAIT); 1721 if (error != 0) { 1722 dmu_tx_abort(tx); 1723 } else { 1724 zvol_log_truncate(zv, tx, df.df_start, 1725 df.df_length, B_TRUE); 1726 dmu_tx_commit(tx); 1727 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 1728 df.df_start, df.df_length); 1729 } 1730 1731 zfs_range_unlock(rl); 1732 1733 if (error == 0) { 1734 /* 1735 * If the write-cache is disabled or 'sync' property 1736 * is set to 'always' then treat this as a synchronous 1737 * operation (i.e. commit to zil). 1738 */ 1739 if (!(zv->zv_flags & ZVOL_WCE) || 1740 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)) 1741 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1742 1743 /* 1744 * If the caller really wants synchronous writes, and 1745 * can't wait for them, don't return until the write 1746 * is done. 1747 */ 1748 if (df.df_flags & DF_WAIT_SYNC) { 1749 txg_wait_synced( 1750 dmu_objset_pool(zv->zv_objset), 0); 1751 } 1752 } 1753 break; 1754 } 1755 1756 default: 1757 error = ENOTTY; 1758 break; 1759 1760 } 1761 mutex_exit(&zfsdev_state_lock); 1762 return (error); 1763 } 1764 1765 int 1766 zvol_busy(void) 1767 { 1768 return (zvol_minors != 0); 1769 } 1770 1771 void 1772 zvol_init(void) 1773 { 1774 VERIFY(ddi_soft_state_init(&zfsdev_state, sizeof (zfs_soft_state_t), 1775 1) == 0); 1776 mutex_init(&zfsdev_state_lock, NULL, MUTEX_DEFAULT, NULL); 1777 } 1778 1779 void 1780 zvol_fini(void) 1781 { 1782 mutex_destroy(&zfsdev_state_lock); 1783 ddi_soft_state_fini(&zfsdev_state); 1784 } 1785 1786 static int 1787 zvol_dump_init(zvol_state_t *zv, boolean_t resize) 1788 { 1789 dmu_tx_t *tx; 1790 int error = 0; 1791 objset_t *os = zv->zv_objset; 1792 nvlist_t *nv = NULL; 1793 uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset)); 1794 1795 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 1796 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 0, 1797 DMU_OBJECT_END); 1798 /* wait for dmu_free_long_range to actually free the blocks */ 1799 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 1800 1801 tx = dmu_tx_create(os); 1802 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 1803 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 1804 error = dmu_tx_assign(tx, TXG_WAIT); 1805 if (error) { 1806 dmu_tx_abort(tx); 1807 return (error); 1808 } 1809 1810 /* 1811 * If we are resizing the dump device then we only need to 1812 * update the refreservation to match the newly updated 1813 * zvolsize. Otherwise, we save off the original state of the 1814 * zvol so that we can restore them if the zvol is ever undumpified. 1815 */ 1816 if (resize) { 1817 error = zap_update(os, ZVOL_ZAP_OBJ, 1818 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 1819 &zv->zv_volsize, tx); 1820 } else { 1821 uint64_t checksum, compress, refresrv, vbs, dedup; 1822 1823 error = dsl_prop_get_integer(zv->zv_name, 1824 zfs_prop_to_name(ZFS_PROP_COMPRESSION), &compress, NULL); 1825 error = error ? error : dsl_prop_get_integer(zv->zv_name, 1826 zfs_prop_to_name(ZFS_PROP_CHECKSUM), &checksum, NULL); 1827 error = error ? error : dsl_prop_get_integer(zv->zv_name, 1828 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &refresrv, NULL); 1829 error = error ? error : dsl_prop_get_integer(zv->zv_name, 1830 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &vbs, NULL); 1831 if (version >= SPA_VERSION_DEDUP) { 1832 error = error ? error : 1833 dsl_prop_get_integer(zv->zv_name, 1834 zfs_prop_to_name(ZFS_PROP_DEDUP), &dedup, NULL); 1835 } 1836 1837 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1838 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, 1839 &compress, tx); 1840 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1841 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum, tx); 1842 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1843 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 1844 &refresrv, tx); 1845 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1846 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, 1847 &vbs, tx); 1848 error = error ? error : dmu_object_set_blocksize( 1849 os, ZVOL_OBJ, SPA_MAXBLOCKSIZE, 0, tx); 1850 if (version >= SPA_VERSION_DEDUP) { 1851 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1852 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, 1853 &dedup, tx); 1854 } 1855 if (error == 0) 1856 zv->zv_volblocksize = SPA_MAXBLOCKSIZE; 1857 } 1858 dmu_tx_commit(tx); 1859 1860 /* 1861 * We only need update the zvol's property if we are initializing 1862 * the dump area for the first time. 1863 */ 1864 if (!resize) { 1865 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 1866 VERIFY(nvlist_add_uint64(nv, 1867 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 0) == 0); 1868 VERIFY(nvlist_add_uint64(nv, 1869 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 1870 ZIO_COMPRESS_OFF) == 0); 1871 VERIFY(nvlist_add_uint64(nv, 1872 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 1873 ZIO_CHECKSUM_OFF) == 0); 1874 if (version >= SPA_VERSION_DEDUP) { 1875 VERIFY(nvlist_add_uint64(nv, 1876 zfs_prop_to_name(ZFS_PROP_DEDUP), 1877 ZIO_CHECKSUM_OFF) == 0); 1878 } 1879 1880 error = zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL, 1881 nv, NULL); 1882 nvlist_free(nv); 1883 1884 if (error) 1885 return (error); 1886 } 1887 1888 /* Allocate the space for the dump */ 1889 error = zvol_prealloc(zv); 1890 return (error); 1891 } 1892 1893 static int 1894 zvol_dumpify(zvol_state_t *zv) 1895 { 1896 int error = 0; 1897 uint64_t dumpsize = 0; 1898 dmu_tx_t *tx; 1899 objset_t *os = zv->zv_objset; 1900 1901 if (zv->zv_flags & ZVOL_RDONLY) 1902 return (EROFS); 1903 1904 if (zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 1905 8, 1, &dumpsize) != 0 || dumpsize != zv->zv_volsize) { 1906 boolean_t resize = (dumpsize > 0); 1907 1908 if ((error = zvol_dump_init(zv, resize)) != 0) { 1909 (void) zvol_dump_fini(zv); 1910 return (error); 1911 } 1912 } 1913 1914 /* 1915 * Build up our lba mapping. 1916 */ 1917 error = zvol_get_lbas(zv); 1918 if (error) { 1919 (void) zvol_dump_fini(zv); 1920 return (error); 1921 } 1922 1923 tx = dmu_tx_create(os); 1924 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 1925 error = dmu_tx_assign(tx, TXG_WAIT); 1926 if (error) { 1927 dmu_tx_abort(tx); 1928 (void) zvol_dump_fini(zv); 1929 return (error); 1930 } 1931 1932 zv->zv_flags |= ZVOL_DUMPIFIED; 1933 error = zap_update(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 8, 1, 1934 &zv->zv_volsize, tx); 1935 dmu_tx_commit(tx); 1936 1937 if (error) { 1938 (void) zvol_dump_fini(zv); 1939 return (error); 1940 } 1941 1942 txg_wait_synced(dmu_objset_pool(os), 0); 1943 return (0); 1944 } 1945 1946 static int 1947 zvol_dump_fini(zvol_state_t *zv) 1948 { 1949 dmu_tx_t *tx; 1950 objset_t *os = zv->zv_objset; 1951 nvlist_t *nv; 1952 int error = 0; 1953 uint64_t checksum, compress, refresrv, vbs, dedup; 1954 uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset)); 1955 1956 /* 1957 * Attempt to restore the zvol back to its pre-dumpified state. 1958 * This is a best-effort attempt as it's possible that not all 1959 * of these properties were initialized during the dumpify process 1960 * (i.e. error during zvol_dump_init). 1961 */ 1962 1963 tx = dmu_tx_create(os); 1964 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 1965 error = dmu_tx_assign(tx, TXG_WAIT); 1966 if (error) { 1967 dmu_tx_abort(tx); 1968 return (error); 1969 } 1970 (void) zap_remove(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, tx); 1971 dmu_tx_commit(tx); 1972 1973 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 1974 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum); 1975 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 1976 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, &compress); 1977 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 1978 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, &refresrv); 1979 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 1980 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, &vbs); 1981 1982 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 1983 (void) nvlist_add_uint64(nv, 1984 zfs_prop_to_name(ZFS_PROP_CHECKSUM), checksum); 1985 (void) nvlist_add_uint64(nv, 1986 zfs_prop_to_name(ZFS_PROP_COMPRESSION), compress); 1987 (void) nvlist_add_uint64(nv, 1988 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), refresrv); 1989 if (version >= SPA_VERSION_DEDUP && 1990 zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 1991 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, &dedup) == 0) { 1992 (void) nvlist_add_uint64(nv, 1993 zfs_prop_to_name(ZFS_PROP_DEDUP), dedup); 1994 } 1995 (void) zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL, 1996 nv, NULL); 1997 nvlist_free(nv); 1998 1999 zvol_free_extents(zv); 2000 zv->zv_flags &= ~ZVOL_DUMPIFIED; 2001 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, DMU_OBJECT_END); 2002 /* wait for dmu_free_long_range to actually free the blocks */ 2003 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 2004 tx = dmu_tx_create(os); 2005 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 2006 error = dmu_tx_assign(tx, TXG_WAIT); 2007 if (error) { 2008 dmu_tx_abort(tx); 2009 return (error); 2010 } 2011 if (dmu_object_set_blocksize(os, ZVOL_OBJ, vbs, 0, tx) == 0) 2012 zv->zv_volblocksize = vbs; 2013 dmu_tx_commit(tx); 2014 2015 return (0); 2016 } 2017