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 2017 Nexenta Systems, Inc. All rights reserved. 27 * Copyright (c) 2012, 2020 by Delphix. All rights reserved. 28 * Copyright (c) 2014 Integros [integros.com] 29 * Copyright 2019 Joyent, Inc. 30 */ 31 32 /* 33 * ZFS volume emulation driver. 34 * 35 * Makes a DMU object look like a volume of arbitrary size, up to 2^64 bytes. 36 * Volumes are accessed through the symbolic links named: 37 * 38 * /dev/zvol/dsk/<pool_name>/<dataset_name> 39 * /dev/zvol/rdsk/<pool_name>/<dataset_name> 40 * 41 * These links are created by the /dev filesystem (sdev_zvolops.c). 42 * Volumes are persistent through reboot. No user command needs to be 43 * run before opening and using a device. 44 */ 45 46 #include <sys/types.h> 47 #include <sys/param.h> 48 #include <sys/errno.h> 49 #include <sys/uio.h> 50 #include <sys/buf.h> 51 #include <sys/modctl.h> 52 #include <sys/open.h> 53 #include <sys/kmem.h> 54 #include <sys/conf.h> 55 #include <sys/cmn_err.h> 56 #include <sys/stat.h> 57 #include <sys/zap.h> 58 #include <sys/spa.h> 59 #include <sys/spa_impl.h> 60 #include <sys/zio.h> 61 #include <sys/dmu_traverse.h> 62 #include <sys/dnode.h> 63 #include <sys/dsl_dataset.h> 64 #include <sys/dsl_prop.h> 65 #include <sys/dkio.h> 66 #include <sys/efi_partition.h> 67 #include <sys/byteorder.h> 68 #include <sys/pathname.h> 69 #include <sys/ddi.h> 70 #include <sys/sunddi.h> 71 #include <sys/crc32.h> 72 #include <sys/dirent.h> 73 #include <sys/policy.h> 74 #include <sys/fs/zfs.h> 75 #include <sys/zfs_ioctl.h> 76 #include <sys/mkdev.h> 77 #include <sys/zil.h> 78 #include <sys/refcount.h> 79 #include <sys/zfs_znode.h> 80 #include <sys/zfs_rlock.h> 81 #include <sys/vdev_impl.h> 82 #include <sys/zvol.h> 83 #include <sys/dumphdr.h> 84 #include <sys/zil_impl.h> 85 #include <sys/dbuf.h> 86 #include <sys/dmu_tx.h> 87 #include <sys/zfeature.h> 88 #include <sys/zio_checksum.h> 89 #include <sys/zil_impl.h> 90 #include <sys/smt.h> 91 #include <sys/dkioc_free_util.h> 92 #include <sys/zfs_rlock.h> 93 94 #include "zfs_namecheck.h" 95 96 void *zfsdev_state; 97 static char *zvol_tag = "zvol_tag"; 98 99 #define ZVOL_DUMPSIZE "dumpsize" 100 101 /* 102 * This lock protects the zfsdev_state structure from being modified 103 * while it's being used, e.g. an open that comes in before a create 104 * finishes. It also protects temporary opens of the dataset so that, 105 * e.g., an open doesn't get a spurious EBUSY. 106 */ 107 kmutex_t zfsdev_state_lock; 108 static uint32_t zvol_minors; 109 110 typedef struct zvol_extent { 111 list_node_t ze_node; 112 dva_t ze_dva; /* dva associated with this extent */ 113 uint64_t ze_nblks; /* number of blocks in extent */ 114 } zvol_extent_t; 115 116 /* 117 * The in-core state of each volume. 118 */ 119 typedef struct zvol_state { 120 char zv_name[MAXPATHLEN]; /* pool/dd name */ 121 uint64_t zv_volsize; /* amount of space we advertise */ 122 uint64_t zv_volblocksize; /* volume block size */ 123 minor_t zv_minor; /* minor number */ 124 uint8_t zv_min_bs; /* minimum addressable block shift */ 125 uint8_t zv_flags; /* readonly, dumpified, etc. */ 126 objset_t *zv_objset; /* objset handle */ 127 uint32_t zv_open_count[OTYPCNT]; /* open counts */ 128 uint32_t zv_total_opens; /* total open count */ 129 zilog_t *zv_zilog; /* ZIL handle */ 130 list_t zv_extents; /* List of extents for dump */ 131 rangelock_t zv_rangelock; 132 dnode_t *zv_dn; /* dnode hold */ 133 } zvol_state_t; 134 135 /* 136 * zvol specific flags 137 */ 138 #define ZVOL_RDONLY 0x1 139 #define ZVOL_DUMPIFIED 0x2 140 #define ZVOL_EXCL 0x4 141 #define ZVOL_WCE 0x8 142 143 /* 144 * zvol maximum transfer in one DMU tx. 145 */ 146 int zvol_maxphys = DMU_MAX_ACCESS/2; 147 148 /* 149 * Toggle unmap functionality. 150 */ 151 boolean_t zvol_unmap_enabled = B_TRUE; 152 153 /* 154 * If true, unmaps requested as synchronous are executed synchronously, 155 * otherwise all unmaps are asynchronous. 156 */ 157 boolean_t zvol_unmap_sync_enabled = B_FALSE; 158 159 extern int zfs_set_prop_nvlist(const char *, zprop_source_t, 160 nvlist_t *, nvlist_t *); 161 static int zvol_remove_zv(zvol_state_t *); 162 static int zvol_get_data(void *arg, lr_write_t *lr, char *buf, 163 struct lwb *lwb, zio_t *zio); 164 static int zvol_dumpify(zvol_state_t *zv); 165 static int zvol_dump_fini(zvol_state_t *zv); 166 static int zvol_dump_init(zvol_state_t *zv, boolean_t resize); 167 168 static void 169 zvol_size_changed(zvol_state_t *zv, uint64_t volsize) 170 { 171 dev_t dev = makedevice(ddi_driver_major(zfs_dip), zv->zv_minor); 172 173 zv->zv_volsize = volsize; 174 VERIFY(ddi_prop_update_int64(dev, zfs_dip, 175 "Size", volsize) == DDI_SUCCESS); 176 VERIFY(ddi_prop_update_int64(dev, zfs_dip, 177 "Nblocks", lbtodb(volsize)) == DDI_SUCCESS); 178 179 /* Notify specfs to invalidate the cached size */ 180 spec_size_invalidate(dev, VBLK); 181 spec_size_invalidate(dev, VCHR); 182 } 183 184 int 185 zvol_check_volsize(uint64_t volsize, uint64_t blocksize) 186 { 187 if (volsize == 0) 188 return (SET_ERROR(EINVAL)); 189 190 if (volsize % blocksize != 0) 191 return (SET_ERROR(EINVAL)); 192 193 #ifdef _ILP32 194 if (volsize - 1 > SPEC_MAXOFFSET_T) 195 return (SET_ERROR(EOVERFLOW)); 196 #endif 197 return (0); 198 } 199 200 int 201 zvol_check_volblocksize(uint64_t volblocksize) 202 { 203 if (volblocksize < SPA_MINBLOCKSIZE || 204 volblocksize > SPA_OLD_MAXBLOCKSIZE || 205 !ISP2(volblocksize)) 206 return (SET_ERROR(EDOM)); 207 208 return (0); 209 } 210 211 int 212 zvol_get_stats(objset_t *os, nvlist_t *nv) 213 { 214 int error; 215 dmu_object_info_t doi; 216 uint64_t val; 217 218 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val); 219 if (error) 220 return (error); 221 222 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val); 223 224 error = dmu_object_info(os, ZVOL_OBJ, &doi); 225 226 if (error == 0) { 227 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE, 228 doi.doi_data_block_size); 229 } 230 231 return (error); 232 } 233 234 static zvol_state_t * 235 zvol_minor_lookup(const char *name) 236 { 237 minor_t minor; 238 zvol_state_t *zv; 239 240 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 241 242 for (minor = 1; minor <= ZFSDEV_MAX_MINOR; minor++) { 243 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 244 if (zv == NULL) 245 continue; 246 if (strcmp(zv->zv_name, name) == 0) 247 return (zv); 248 } 249 250 return (NULL); 251 } 252 253 /* extent mapping arg */ 254 struct maparg { 255 zvol_state_t *ma_zv; 256 uint64_t ma_blks; 257 }; 258 259 /*ARGSUSED*/ 260 static int 261 zvol_map_block(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, 262 const zbookmark_phys_t *zb, const dnode_phys_t *dnp, void *arg) 263 { 264 struct maparg *ma = arg; 265 zvol_extent_t *ze; 266 int bs = ma->ma_zv->zv_volblocksize; 267 268 if (bp == NULL || BP_IS_HOLE(bp) || 269 zb->zb_object != ZVOL_OBJ || zb->zb_level != 0) 270 return (0); 271 272 VERIFY(!BP_IS_EMBEDDED(bp)); 273 274 VERIFY3U(ma->ma_blks, ==, zb->zb_blkid); 275 ma->ma_blks++; 276 277 /* Abort immediately if we have encountered gang blocks */ 278 if (BP_IS_GANG(bp)) 279 return (SET_ERROR(EFRAGS)); 280 281 /* 282 * See if the block is at the end of the previous extent. 283 */ 284 ze = list_tail(&ma->ma_zv->zv_extents); 285 if (ze && 286 DVA_GET_VDEV(BP_IDENTITY(bp)) == DVA_GET_VDEV(&ze->ze_dva) && 287 DVA_GET_OFFSET(BP_IDENTITY(bp)) == 288 DVA_GET_OFFSET(&ze->ze_dva) + ze->ze_nblks * bs) { 289 ze->ze_nblks++; 290 return (0); 291 } 292 293 dprintf_bp(bp, "%s", "next blkptr:"); 294 295 /* start a new extent */ 296 ze = kmem_zalloc(sizeof (zvol_extent_t), KM_SLEEP); 297 ze->ze_dva = bp->blk_dva[0]; /* structure assignment */ 298 ze->ze_nblks = 1; 299 list_insert_tail(&ma->ma_zv->zv_extents, ze); 300 return (0); 301 } 302 303 static void 304 zvol_free_extents(zvol_state_t *zv) 305 { 306 zvol_extent_t *ze; 307 308 while (ze = list_head(&zv->zv_extents)) { 309 list_remove(&zv->zv_extents, ze); 310 kmem_free(ze, sizeof (zvol_extent_t)); 311 } 312 } 313 314 static int 315 zvol_get_lbas(zvol_state_t *zv) 316 { 317 objset_t *os = zv->zv_objset; 318 struct maparg ma; 319 int err; 320 321 ma.ma_zv = zv; 322 ma.ma_blks = 0; 323 zvol_free_extents(zv); 324 325 /* commit any in-flight changes before traversing the dataset */ 326 txg_wait_synced(dmu_objset_pool(os), 0); 327 err = traverse_dataset(dmu_objset_ds(os), 0, 328 TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA, zvol_map_block, &ma); 329 if (err || ma.ma_blks != (zv->zv_volsize / zv->zv_volblocksize)) { 330 zvol_free_extents(zv); 331 return (err ? err : EIO); 332 } 333 334 return (0); 335 } 336 337 /* ARGSUSED */ 338 void 339 zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx) 340 { 341 zfs_creat_t *zct = arg; 342 nvlist_t *nvprops = zct->zct_props; 343 int error; 344 uint64_t volblocksize, volsize; 345 346 VERIFY(nvlist_lookup_uint64(nvprops, 347 zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0); 348 if (nvlist_lookup_uint64(nvprops, 349 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0) 350 volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE); 351 352 /* 353 * These properties must be removed from the list so the generic 354 * property setting step won't apply to them. 355 */ 356 VERIFY(nvlist_remove_all(nvprops, 357 zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0); 358 (void) nvlist_remove_all(nvprops, 359 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE)); 360 361 error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize, 362 DMU_OT_NONE, 0, tx); 363 ASSERT(error == 0); 364 365 error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP, 366 DMU_OT_NONE, 0, tx); 367 ASSERT(error == 0); 368 369 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx); 370 ASSERT(error == 0); 371 } 372 373 /* 374 * Replay a TX_TRUNCATE ZIL transaction if asked. TX_TRUNCATE is how we 375 * implement DKIOCFREE/free-long-range. 376 */ 377 static int 378 zvol_replay_truncate(void *arg1, void *arg2, boolean_t byteswap) 379 { 380 zvol_state_t *zv = arg1; 381 lr_truncate_t *lr = arg2; 382 uint64_t offset, length; 383 384 if (byteswap) 385 byteswap_uint64_array(lr, sizeof (*lr)); 386 387 offset = lr->lr_offset; 388 length = lr->lr_length; 389 390 return (dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, offset, length)); 391 } 392 393 /* 394 * Replay a TX_WRITE ZIL transaction that didn't get committed 395 * after a system failure 396 */ 397 /* ARGSUSED */ 398 static int 399 zvol_replay_write(void *arg1, void *arg2, boolean_t byteswap) 400 { 401 zvol_state_t *zv = arg1; 402 lr_write_t *lr = arg2; 403 objset_t *os = zv->zv_objset; 404 char *data = (char *)(lr + 1); /* data follows lr_write_t */ 405 uint64_t offset, length; 406 dmu_tx_t *tx; 407 int error; 408 409 if (byteswap) 410 byteswap_uint64_array(lr, sizeof (*lr)); 411 412 offset = lr->lr_offset; 413 length = lr->lr_length; 414 415 /* If it's a dmu_sync() block, write the whole block */ 416 if (lr->lr_common.lrc_reclen == sizeof (lr_write_t)) { 417 uint64_t blocksize = BP_GET_LSIZE(&lr->lr_blkptr); 418 if (length < blocksize) { 419 offset -= offset % blocksize; 420 length = blocksize; 421 } 422 } 423 424 tx = dmu_tx_create(os); 425 dmu_tx_hold_write(tx, ZVOL_OBJ, offset, length); 426 error = dmu_tx_assign(tx, TXG_WAIT); 427 if (error) { 428 dmu_tx_abort(tx); 429 } else { 430 dmu_write(os, ZVOL_OBJ, offset, length, data, tx); 431 dmu_tx_commit(tx); 432 } 433 434 return (error); 435 } 436 437 /* ARGSUSED */ 438 static int 439 zvol_replay_err(void *arg1, void *arg2, boolean_t byteswap) 440 { 441 return (SET_ERROR(ENOTSUP)); 442 } 443 444 /* 445 * Callback vectors for replaying records. 446 * Only TX_WRITE and TX_TRUNCATE are needed for zvol. 447 */ 448 zil_replay_func_t *zvol_replay_vector[TX_MAX_TYPE] = { 449 zvol_replay_err, /* 0 no such transaction type */ 450 zvol_replay_err, /* TX_CREATE */ 451 zvol_replay_err, /* TX_MKDIR */ 452 zvol_replay_err, /* TX_MKXATTR */ 453 zvol_replay_err, /* TX_SYMLINK */ 454 zvol_replay_err, /* TX_REMOVE */ 455 zvol_replay_err, /* TX_RMDIR */ 456 zvol_replay_err, /* TX_LINK */ 457 zvol_replay_err, /* TX_RENAME */ 458 zvol_replay_write, /* TX_WRITE */ 459 zvol_replay_truncate, /* TX_TRUNCATE */ 460 zvol_replay_err, /* TX_SETATTR */ 461 zvol_replay_err, /* TX_ACL */ 462 zvol_replay_err, /* TX_CREATE_ACL */ 463 zvol_replay_err, /* TX_CREATE_ATTR */ 464 zvol_replay_err, /* TX_CREATE_ACL_ATTR */ 465 zvol_replay_err, /* TX_MKDIR_ACL */ 466 zvol_replay_err, /* TX_MKDIR_ATTR */ 467 zvol_replay_err, /* TX_MKDIR_ACL_ATTR */ 468 zvol_replay_err, /* TX_WRITE2 */ 469 }; 470 471 int 472 zvol_name2minor(const char *name, minor_t *minor) 473 { 474 zvol_state_t *zv; 475 476 mutex_enter(&zfsdev_state_lock); 477 zv = zvol_minor_lookup(name); 478 if (minor && zv) 479 *minor = zv->zv_minor; 480 mutex_exit(&zfsdev_state_lock); 481 return (zv ? 0 : -1); 482 } 483 484 /* 485 * Create a minor node (plus a whole lot more) for the specified volume. 486 */ 487 int 488 zvol_create_minor(const char *name) 489 { 490 zfs_soft_state_t *zs; 491 zvol_state_t *zv; 492 objset_t *os; 493 dmu_object_info_t doi; 494 minor_t minor = 0; 495 char chrbuf[30], blkbuf[30]; 496 int error; 497 498 mutex_enter(&zfsdev_state_lock); 499 500 if (zvol_minor_lookup(name) != NULL) { 501 mutex_exit(&zfsdev_state_lock); 502 return (SET_ERROR(EEXIST)); 503 } 504 505 /* lie and say we're read-only */ 506 error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, B_TRUE, FTAG, &os); 507 508 if (error) { 509 mutex_exit(&zfsdev_state_lock); 510 return (error); 511 } 512 513 if ((minor = zfsdev_minor_alloc()) == 0) { 514 dmu_objset_disown(os, 1, FTAG); 515 mutex_exit(&zfsdev_state_lock); 516 return (SET_ERROR(ENXIO)); 517 } 518 519 if (ddi_soft_state_zalloc(zfsdev_state, minor) != DDI_SUCCESS) { 520 dmu_objset_disown(os, 1, FTAG); 521 mutex_exit(&zfsdev_state_lock); 522 return (SET_ERROR(EAGAIN)); 523 } 524 (void) ddi_prop_update_string(minor, zfs_dip, ZVOL_PROP_NAME, 525 (char *)name); 526 527 (void) snprintf(chrbuf, sizeof (chrbuf), "%u,raw", minor); 528 529 if (ddi_create_minor_node(zfs_dip, chrbuf, S_IFCHR, 530 minor, DDI_PSEUDO, 0) == DDI_FAILURE) { 531 ddi_soft_state_free(zfsdev_state, minor); 532 dmu_objset_disown(os, 1, FTAG); 533 mutex_exit(&zfsdev_state_lock); 534 return (SET_ERROR(EAGAIN)); 535 } 536 537 (void) snprintf(blkbuf, sizeof (blkbuf), "%u", minor); 538 539 if (ddi_create_minor_node(zfs_dip, blkbuf, S_IFBLK, 540 minor, DDI_PSEUDO, 0) == DDI_FAILURE) { 541 ddi_remove_minor_node(zfs_dip, chrbuf); 542 ddi_soft_state_free(zfsdev_state, minor); 543 dmu_objset_disown(os, 1, FTAG); 544 mutex_exit(&zfsdev_state_lock); 545 return (SET_ERROR(EAGAIN)); 546 } 547 548 zs = ddi_get_soft_state(zfsdev_state, minor); 549 zs->zss_type = ZSST_ZVOL; 550 zv = zs->zss_data = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP); 551 (void) strlcpy(zv->zv_name, name, MAXPATHLEN); 552 zv->zv_min_bs = DEV_BSHIFT; 553 zv->zv_minor = minor; 554 zv->zv_objset = os; 555 if (dmu_objset_is_snapshot(os) || !spa_writeable(dmu_objset_spa(os))) 556 zv->zv_flags |= ZVOL_RDONLY; 557 rangelock_init(&zv->zv_rangelock, NULL, NULL); 558 list_create(&zv->zv_extents, sizeof (zvol_extent_t), 559 offsetof(zvol_extent_t, ze_node)); 560 /* get and cache the blocksize */ 561 error = dmu_object_info(os, ZVOL_OBJ, &doi); 562 ASSERT(error == 0); 563 zv->zv_volblocksize = doi.doi_data_block_size; 564 565 if (spa_writeable(dmu_objset_spa(os))) { 566 if (zil_replay_disable) 567 zil_destroy(dmu_objset_zil(os), B_FALSE); 568 else 569 zil_replay(os, zv, zvol_replay_vector); 570 } 571 dmu_objset_disown(os, 1, FTAG); 572 zv->zv_objset = NULL; 573 574 zvol_minors++; 575 576 mutex_exit(&zfsdev_state_lock); 577 578 return (0); 579 } 580 581 /* 582 * Remove minor node for the specified volume. 583 */ 584 static int 585 zvol_remove_zv(zvol_state_t *zv) 586 { 587 char nmbuf[20]; 588 minor_t minor = zv->zv_minor; 589 590 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 591 if (zv->zv_total_opens != 0) 592 return (SET_ERROR(EBUSY)); 593 594 (void) snprintf(nmbuf, sizeof (nmbuf), "%u,raw", minor); 595 ddi_remove_minor_node(zfs_dip, nmbuf); 596 597 (void) snprintf(nmbuf, sizeof (nmbuf), "%u", minor); 598 ddi_remove_minor_node(zfs_dip, nmbuf); 599 600 rangelock_fini(&zv->zv_rangelock); 601 602 kmem_free(zv, sizeof (zvol_state_t)); 603 604 ddi_soft_state_free(zfsdev_state, minor); 605 606 zvol_minors--; 607 return (0); 608 } 609 610 int 611 zvol_remove_minor(const char *name) 612 { 613 zvol_state_t *zv; 614 int rc; 615 616 mutex_enter(&zfsdev_state_lock); 617 if ((zv = zvol_minor_lookup(name)) == NULL) { 618 mutex_exit(&zfsdev_state_lock); 619 return (SET_ERROR(ENXIO)); 620 } 621 rc = zvol_remove_zv(zv); 622 mutex_exit(&zfsdev_state_lock); 623 return (rc); 624 } 625 626 int 627 zvol_first_open(zvol_state_t *zv, boolean_t rdonly) 628 { 629 objset_t *os; 630 uint64_t volsize; 631 int error; 632 uint64_t readonly; 633 boolean_t ro; 634 635 ro = (rdonly || (strchr(zv->zv_name, '@') != NULL)); 636 error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, ro, B_TRUE, zv, &os); 637 if (error) 638 return (error); 639 640 zv->zv_objset = os; 641 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize); 642 if (error) { 643 ASSERT(error == 0); 644 dmu_objset_disown(os, 1, zv); 645 return (error); 646 } 647 648 error = dnode_hold(os, ZVOL_OBJ, zvol_tag, &zv->zv_dn); 649 if (error) { 650 dmu_objset_disown(os, 1, zv); 651 return (error); 652 } 653 654 zvol_size_changed(zv, volsize); 655 zv->zv_zilog = zil_open(os, zvol_get_data); 656 657 VERIFY(dsl_prop_get_integer(zv->zv_name, "readonly", &readonly, 658 NULL) == 0); 659 if (readonly || dmu_objset_is_snapshot(os) || 660 !spa_writeable(dmu_objset_spa(os))) 661 zv->zv_flags |= ZVOL_RDONLY; 662 else 663 zv->zv_flags &= ~ZVOL_RDONLY; 664 return (error); 665 } 666 667 void 668 zvol_last_close(zvol_state_t *zv) 669 { 670 zil_close(zv->zv_zilog); 671 zv->zv_zilog = NULL; 672 673 dnode_rele(zv->zv_dn, zvol_tag); 674 zv->zv_dn = NULL; 675 676 /* 677 * Evict cached data 678 */ 679 if (dsl_dataset_is_dirty(dmu_objset_ds(zv->zv_objset)) && 680 !(zv->zv_flags & ZVOL_RDONLY)) 681 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 682 dmu_objset_evict_dbufs(zv->zv_objset); 683 684 dmu_objset_disown(zv->zv_objset, 1, zv); 685 zv->zv_objset = NULL; 686 } 687 688 int 689 zvol_prealloc(zvol_state_t *zv) 690 { 691 objset_t *os = zv->zv_objset; 692 dmu_tx_t *tx; 693 uint64_t refd, avail, usedobjs, availobjs; 694 uint64_t resid = zv->zv_volsize; 695 uint64_t off = 0; 696 697 /* Check the space usage before attempting to allocate the space */ 698 dmu_objset_space(os, &refd, &avail, &usedobjs, &availobjs); 699 if (avail < zv->zv_volsize) 700 return (SET_ERROR(ENOSPC)); 701 702 /* Free old extents if they exist */ 703 zvol_free_extents(zv); 704 705 while (resid != 0) { 706 int error; 707 uint64_t bytes = MIN(resid, SPA_OLD_MAXBLOCKSIZE); 708 709 tx = dmu_tx_create(os); 710 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes); 711 error = dmu_tx_assign(tx, TXG_WAIT); 712 if (error) { 713 dmu_tx_abort(tx); 714 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, off); 715 return (error); 716 } 717 dmu_prealloc(os, ZVOL_OBJ, off, bytes, tx); 718 dmu_tx_commit(tx); 719 off += bytes; 720 resid -= bytes; 721 } 722 txg_wait_synced(dmu_objset_pool(os), 0); 723 724 return (0); 725 } 726 727 static int 728 zvol_update_volsize(objset_t *os, uint64_t volsize) 729 { 730 dmu_tx_t *tx; 731 int error; 732 uint64_t txg; 733 734 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 735 736 tx = dmu_tx_create(os); 737 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 738 dmu_tx_mark_netfree(tx); 739 error = dmu_tx_assign(tx, TXG_WAIT); 740 if (error) { 741 dmu_tx_abort(tx); 742 return (error); 743 } 744 txg = dmu_tx_get_txg(tx); 745 746 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, 747 &volsize, tx); 748 dmu_tx_commit(tx); 749 750 txg_wait_synced(dmu_objset_pool(os), txg); 751 752 if (error == 0) 753 error = dmu_free_long_range(os, 754 ZVOL_OBJ, volsize, DMU_OBJECT_END); 755 return (error); 756 } 757 758 void 759 zvol_remove_minors(const char *name) 760 { 761 zvol_state_t *zv; 762 char *namebuf; 763 minor_t minor; 764 765 namebuf = kmem_zalloc(strlen(name) + 2, KM_SLEEP); 766 (void) strncpy(namebuf, name, strlen(name)); 767 (void) strcat(namebuf, "/"); 768 mutex_enter(&zfsdev_state_lock); 769 for (minor = 1; minor <= ZFSDEV_MAX_MINOR; minor++) { 770 771 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 772 if (zv == NULL) 773 continue; 774 if (strncmp(namebuf, zv->zv_name, strlen(namebuf)) == 0) 775 (void) zvol_remove_zv(zv); 776 } 777 kmem_free(namebuf, strlen(name) + 2); 778 779 mutex_exit(&zfsdev_state_lock); 780 } 781 782 static int 783 zvol_update_live_volsize(zvol_state_t *zv, uint64_t volsize) 784 { 785 uint64_t old_volsize = 0ULL; 786 int error = 0; 787 788 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 789 790 /* 791 * Reinitialize the dump area to the new size. If we 792 * failed to resize the dump area then restore it back to 793 * its original size. We must set the new volsize prior 794 * to calling dumpvp_resize() to ensure that the devices' 795 * size(9P) is not visible by the dump subsystem. 796 */ 797 old_volsize = zv->zv_volsize; 798 zvol_size_changed(zv, volsize); 799 800 if (zv->zv_flags & ZVOL_DUMPIFIED) { 801 if ((error = zvol_dumpify(zv)) != 0 || 802 (error = dumpvp_resize()) != 0) { 803 int dumpify_error; 804 805 (void) zvol_update_volsize(zv->zv_objset, old_volsize); 806 zvol_size_changed(zv, old_volsize); 807 dumpify_error = zvol_dumpify(zv); 808 error = dumpify_error ? dumpify_error : error; 809 } 810 } 811 812 /* 813 * Generate a LUN expansion event. 814 */ 815 if (error == 0) { 816 char *physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 817 818 (void) snprintf(physpath, MAXPATHLEN, "%s%u", ZVOL_PSEUDO_DEV, 819 zv->zv_minor); 820 821 zfs_post_dle_sysevent(physpath); 822 kmem_free(physpath, MAXPATHLEN); 823 } 824 return (error); 825 } 826 827 int 828 zvol_set_volsize(const char *name, uint64_t volsize) 829 { 830 zvol_state_t *zv = NULL; 831 objset_t *os; 832 int error; 833 dmu_object_info_t doi; 834 uint64_t readonly; 835 boolean_t owned = B_FALSE; 836 837 error = dsl_prop_get_integer(name, 838 zfs_prop_to_name(ZFS_PROP_READONLY), &readonly, NULL); 839 if (error != 0) 840 return (error); 841 if (readonly) 842 return (SET_ERROR(EROFS)); 843 844 mutex_enter(&zfsdev_state_lock); 845 zv = zvol_minor_lookup(name); 846 847 if (zv == NULL || zv->zv_objset == NULL) { 848 if ((error = dmu_objset_own(name, DMU_OST_ZVOL, B_FALSE, B_TRUE, 849 FTAG, &os)) != 0) { 850 mutex_exit(&zfsdev_state_lock); 851 return (error); 852 } 853 owned = B_TRUE; 854 if (zv != NULL) 855 zv->zv_objset = os; 856 } else { 857 os = zv->zv_objset; 858 } 859 860 if ((error = dmu_object_info(os, ZVOL_OBJ, &doi)) != 0 || 861 (error = zvol_check_volsize(volsize, doi.doi_data_block_size)) != 0) 862 goto out; 863 864 error = zvol_update_volsize(os, volsize); 865 866 if (error == 0 && zv != NULL) 867 error = zvol_update_live_volsize(zv, volsize); 868 out: 869 if (owned) { 870 dmu_objset_disown(os, B_TRUE, FTAG); 871 if (zv != NULL) 872 zv->zv_objset = NULL; 873 } 874 mutex_exit(&zfsdev_state_lock); 875 return (error); 876 } 877 878 /*ARGSUSED*/ 879 int 880 zvol_open(dev_t *devp, int flag, int otyp, cred_t *cr) 881 { 882 zvol_state_t *zv; 883 int err = 0; 884 885 mutex_enter(&zfsdev_state_lock); 886 887 zv = zfsdev_get_soft_state(getminor(*devp), ZSST_ZVOL); 888 if (zv == NULL) { 889 mutex_exit(&zfsdev_state_lock); 890 return (SET_ERROR(ENXIO)); 891 } 892 893 if (zv->zv_total_opens == 0) 894 err = zvol_first_open(zv, !(flag & FWRITE)); 895 if (err) { 896 mutex_exit(&zfsdev_state_lock); 897 return (err); 898 } 899 900 if ((flag & FWRITE) && (zv->zv_flags & ZVOL_RDONLY)) { 901 err = SET_ERROR(EROFS); 902 goto out; 903 } 904 if (zv->zv_flags & ZVOL_EXCL) { 905 err = SET_ERROR(EBUSY); 906 goto out; 907 } 908 if (flag & FEXCL) { 909 if (zv->zv_total_opens != 0) { 910 err = SET_ERROR(EBUSY); 911 goto out; 912 } 913 zv->zv_flags |= ZVOL_EXCL; 914 } 915 916 if (zv->zv_open_count[otyp] == 0 || otyp == OTYP_LYR) { 917 zv->zv_open_count[otyp]++; 918 zv->zv_total_opens++; 919 } 920 mutex_exit(&zfsdev_state_lock); 921 922 return (err); 923 out: 924 if (zv->zv_total_opens == 0) 925 zvol_last_close(zv); 926 mutex_exit(&zfsdev_state_lock); 927 return (err); 928 } 929 930 /*ARGSUSED*/ 931 int 932 zvol_close(dev_t dev, int flag, int otyp, cred_t *cr) 933 { 934 minor_t minor = getminor(dev); 935 zvol_state_t *zv; 936 int error = 0; 937 938 mutex_enter(&zfsdev_state_lock); 939 940 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 941 if (zv == NULL) { 942 mutex_exit(&zfsdev_state_lock); 943 return (SET_ERROR(ENXIO)); 944 } 945 946 if (zv->zv_flags & ZVOL_EXCL) { 947 ASSERT(zv->zv_total_opens == 1); 948 zv->zv_flags &= ~ZVOL_EXCL; 949 } 950 951 /* 952 * If the open count is zero, this is a spurious close. 953 * That indicates a bug in the kernel / DDI framework. 954 */ 955 ASSERT(zv->zv_open_count[otyp] != 0); 956 ASSERT(zv->zv_total_opens != 0); 957 958 /* 959 * You may get multiple opens, but only one close. 960 */ 961 zv->zv_open_count[otyp]--; 962 zv->zv_total_opens--; 963 964 if (zv->zv_total_opens == 0) 965 zvol_last_close(zv); 966 967 mutex_exit(&zfsdev_state_lock); 968 return (error); 969 } 970 971 /* ARGSUSED */ 972 static void 973 zvol_get_done(zgd_t *zgd, int error) 974 { 975 if (zgd->zgd_db) 976 dmu_buf_rele(zgd->zgd_db, zgd); 977 978 rangelock_exit(zgd->zgd_lr); 979 980 kmem_free(zgd, sizeof (zgd_t)); 981 } 982 983 /* 984 * Get data to generate a TX_WRITE intent log record. 985 */ 986 static int 987 zvol_get_data(void *arg, lr_write_t *lr, char *buf, struct lwb *lwb, zio_t *zio) 988 { 989 zvol_state_t *zv = arg; 990 uint64_t offset = lr->lr_offset; 991 uint64_t size = lr->lr_length; /* length of user data */ 992 dmu_buf_t *db; 993 zgd_t *zgd; 994 int error; 995 996 ASSERT3P(lwb, !=, NULL); 997 ASSERT3P(zio, !=, NULL); 998 ASSERT3U(size, !=, 0); 999 1000 zgd = kmem_zalloc(sizeof (zgd_t), KM_SLEEP); 1001 zgd->zgd_lwb = lwb; 1002 1003 /* 1004 * Write records come in two flavors: immediate and indirect. 1005 * For small writes it's cheaper to store the data with the 1006 * log record (immediate); for large writes it's cheaper to 1007 * sync the data and get a pointer to it (indirect) so that 1008 * we don't have to write the data twice. 1009 */ 1010 if (buf != NULL) { /* immediate write */ 1011 zgd->zgd_lr = rangelock_enter(&zv->zv_rangelock, offset, size, 1012 RL_READER); 1013 error = dmu_read_by_dnode(zv->zv_dn, offset, size, buf, 1014 DMU_READ_NO_PREFETCH); 1015 } else { /* indirect write */ 1016 /* 1017 * Have to lock the whole block to ensure when it's written out 1018 * and its checksum is being calculated that no one can change 1019 * the data. Contrarily to zfs_get_data we need not re-check 1020 * blocksize after we get the lock because it cannot be changed. 1021 */ 1022 size = zv->zv_volblocksize; 1023 offset = P2ALIGN(offset, size); 1024 zgd->zgd_lr = rangelock_enter(&zv->zv_rangelock, offset, size, 1025 RL_READER); 1026 error = dmu_buf_hold_by_dnode(zv->zv_dn, offset, zgd, &db, 1027 DMU_READ_NO_PREFETCH); 1028 if (error == 0) { 1029 blkptr_t *bp = &lr->lr_blkptr; 1030 1031 zgd->zgd_db = db; 1032 zgd->zgd_bp = bp; 1033 1034 ASSERT(db->db_offset == offset); 1035 ASSERT(db->db_size == size); 1036 1037 error = dmu_sync(zio, lr->lr_common.lrc_txg, 1038 zvol_get_done, zgd); 1039 1040 if (error == 0) 1041 return (0); 1042 } 1043 } 1044 1045 zvol_get_done(zgd, error); 1046 1047 return (error); 1048 } 1049 1050 /* 1051 * zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions. 1052 * 1053 * We store data in the log buffers if it's small enough. 1054 * Otherwise we will later flush the data out via dmu_sync(). 1055 */ 1056 ssize_t zvol_immediate_write_sz = 32768; 1057 1058 static void 1059 zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, offset_t off, ssize_t resid, 1060 boolean_t sync) 1061 { 1062 uint32_t blocksize = zv->zv_volblocksize; 1063 zilog_t *zilog = zv->zv_zilog; 1064 itx_wr_state_t write_state; 1065 1066 if (zil_replaying(zilog, tx)) 1067 return; 1068 1069 if (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT) 1070 write_state = WR_INDIRECT; 1071 else if (!spa_has_slogs(zilog->zl_spa) && 1072 resid >= blocksize && blocksize > zvol_immediate_write_sz) 1073 write_state = WR_INDIRECT; 1074 else if (sync) 1075 write_state = WR_COPIED; 1076 else 1077 write_state = WR_NEED_COPY; 1078 1079 while (resid) { 1080 itx_t *itx; 1081 lr_write_t *lr; 1082 itx_wr_state_t wr_state = write_state; 1083 ssize_t len = resid; 1084 1085 if (wr_state == WR_COPIED && resid > ZIL_MAX_COPIED_DATA) 1086 wr_state = WR_NEED_COPY; 1087 else if (wr_state == WR_INDIRECT) 1088 len = MIN(blocksize - P2PHASE(off, blocksize), resid); 1089 1090 itx = zil_itx_create(TX_WRITE, sizeof (*lr) + 1091 (wr_state == WR_COPIED ? len : 0)); 1092 lr = (lr_write_t *)&itx->itx_lr; 1093 if (wr_state == WR_COPIED && dmu_read_by_dnode(zv->zv_dn, 1094 off, len, lr + 1, DMU_READ_NO_PREFETCH) != 0) { 1095 zil_itx_destroy(itx); 1096 itx = zil_itx_create(TX_WRITE, sizeof (*lr)); 1097 lr = (lr_write_t *)&itx->itx_lr; 1098 wr_state = WR_NEED_COPY; 1099 } 1100 1101 itx->itx_wr_state = wr_state; 1102 lr->lr_foid = ZVOL_OBJ; 1103 lr->lr_offset = off; 1104 lr->lr_length = len; 1105 lr->lr_blkoff = 0; 1106 BP_ZERO(&lr->lr_blkptr); 1107 1108 itx->itx_private = zv; 1109 itx->itx_sync = sync; 1110 1111 zil_itx_assign(zilog, itx, tx); 1112 1113 off += len; 1114 resid -= len; 1115 } 1116 } 1117 1118 static int 1119 zvol_dumpio_vdev(vdev_t *vd, void *addr, uint64_t offset, uint64_t origoffset, 1120 uint64_t size, boolean_t doread, boolean_t isdump) 1121 { 1122 if (doread && !vdev_readable(vd)) 1123 return (SET_ERROR(EIO)); 1124 if (!doread && !vdev_writeable(vd)) 1125 return (SET_ERROR(EIO)); 1126 if (vd->vdev_ops->vdev_op_dumpio == NULL) 1127 return (SET_ERROR(EIO)); 1128 1129 return (vd->vdev_ops->vdev_op_dumpio(vd, addr, size, 1130 offset, origoffset, doread, isdump)); 1131 } 1132 1133 static int 1134 zvol_dumpio(zvol_state_t *zv, void *addr, uint64_t offset, uint64_t size, 1135 boolean_t doread, boolean_t isdump) 1136 { 1137 vdev_t *vd; 1138 int error; 1139 zvol_extent_t *ze; 1140 spa_t *spa = dmu_objset_spa(zv->zv_objset); 1141 1142 /* Must be sector aligned, and not stradle a block boundary. */ 1143 if (P2PHASE(offset, DEV_BSIZE) || P2PHASE(size, DEV_BSIZE) || 1144 P2BOUNDARY(offset, size, zv->zv_volblocksize)) { 1145 return (SET_ERROR(EINVAL)); 1146 } 1147 VERIFY3U(size, <=, zv->zv_volblocksize); 1148 1149 /* Locate the extent this belongs to */ 1150 for (ze = list_head(&zv->zv_extents); 1151 ze != NULL && offset >= ze->ze_nblks * zv->zv_volblocksize; 1152 ze = list_next(&zv->zv_extents, ze)) { 1153 offset -= ze->ze_nblks * zv->zv_volblocksize; 1154 } 1155 1156 if (ze == NULL) 1157 return (SET_ERROR(EINVAL)); 1158 1159 if (!ddi_in_panic()) 1160 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER); 1161 1162 vd = vdev_lookup_top(spa, DVA_GET_VDEV(&ze->ze_dva)); 1163 offset += DVA_GET_OFFSET(&ze->ze_dva); 1164 error = zvol_dumpio_vdev(vd, addr, offset, DVA_GET_OFFSET(&ze->ze_dva), 1165 size, doread, isdump); 1166 1167 if (!ddi_in_panic()) 1168 spa_config_exit(spa, SCL_STATE, FTAG); 1169 1170 return (error); 1171 } 1172 1173 int 1174 zvol_strategy(buf_t *bp) 1175 { 1176 zfs_soft_state_t *zs = NULL; 1177 zvol_state_t *zv; 1178 uint64_t off, volsize; 1179 size_t resid; 1180 char *addr; 1181 objset_t *os; 1182 int error = 0; 1183 boolean_t doread = !!(bp->b_flags & B_READ); 1184 boolean_t is_dumpified; 1185 boolean_t sync; 1186 1187 if (getminor(bp->b_edev) == 0) { 1188 error = SET_ERROR(EINVAL); 1189 } else { 1190 zs = ddi_get_soft_state(zfsdev_state, getminor(bp->b_edev)); 1191 if (zs == NULL) 1192 error = SET_ERROR(ENXIO); 1193 else if (zs->zss_type != ZSST_ZVOL) 1194 error = SET_ERROR(EINVAL); 1195 } 1196 1197 if (error) { 1198 bioerror(bp, error); 1199 biodone(bp); 1200 return (0); 1201 } 1202 1203 zv = zs->zss_data; 1204 1205 if (!(bp->b_flags & B_READ) && (zv->zv_flags & ZVOL_RDONLY)) { 1206 bioerror(bp, EROFS); 1207 biodone(bp); 1208 return (0); 1209 } 1210 1211 off = ldbtob(bp->b_blkno); 1212 volsize = zv->zv_volsize; 1213 1214 os = zv->zv_objset; 1215 ASSERT(os != NULL); 1216 1217 bp_mapin(bp); 1218 addr = bp->b_un.b_addr; 1219 resid = bp->b_bcount; 1220 1221 if (resid > 0 && off >= volsize) { 1222 bioerror(bp, EIO); 1223 biodone(bp); 1224 return (0); 1225 } 1226 1227 is_dumpified = zv->zv_flags & ZVOL_DUMPIFIED; 1228 sync = ((!(bp->b_flags & B_ASYNC) && 1229 !(zv->zv_flags & ZVOL_WCE)) || 1230 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)) && 1231 !doread && !is_dumpified; 1232 1233 smt_begin_unsafe(); 1234 1235 /* 1236 * There must be no buffer changes when doing a dmu_sync() because 1237 * we can't change the data whilst calculating the checksum. 1238 */ 1239 locked_range_t *lr = rangelock_enter(&zv->zv_rangelock, off, resid, 1240 doread ? RL_READER : RL_WRITER); 1241 1242 while (resid != 0 && off < volsize) { 1243 size_t size = MIN(resid, zvol_maxphys); 1244 if (is_dumpified) { 1245 size = MIN(size, P2END(off, zv->zv_volblocksize) - off); 1246 error = zvol_dumpio(zv, addr, off, size, 1247 doread, B_FALSE); 1248 } else if (doread) { 1249 error = dmu_read(os, ZVOL_OBJ, off, size, addr, 1250 DMU_READ_PREFETCH); 1251 } else { 1252 dmu_tx_t *tx = dmu_tx_create(os); 1253 dmu_tx_hold_write(tx, ZVOL_OBJ, off, size); 1254 error = dmu_tx_assign(tx, TXG_WAIT); 1255 if (error) { 1256 dmu_tx_abort(tx); 1257 } else { 1258 dmu_write(os, ZVOL_OBJ, off, size, addr, tx); 1259 zvol_log_write(zv, tx, off, size, sync); 1260 dmu_tx_commit(tx); 1261 } 1262 } 1263 if (error) { 1264 /* convert checksum errors into IO errors */ 1265 if (error == ECKSUM) 1266 error = SET_ERROR(EIO); 1267 break; 1268 } 1269 off += size; 1270 addr += size; 1271 resid -= size; 1272 } 1273 rangelock_exit(lr); 1274 1275 if ((bp->b_resid = resid) == bp->b_bcount) 1276 bioerror(bp, off > volsize ? EINVAL : error); 1277 1278 if (sync) 1279 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1280 biodone(bp); 1281 1282 smt_end_unsafe(); 1283 1284 return (0); 1285 } 1286 1287 /* 1288 * Set the buffer count to the zvol maximum transfer. 1289 * Using our own routine instead of the default minphys() 1290 * means that for larger writes we write bigger buffers on X86 1291 * (128K instead of 56K) and flush the disk write cache less often 1292 * (every zvol_maxphys - currently 1MB) instead of minphys (currently 1293 * 56K on X86 and 128K on sparc). 1294 */ 1295 void 1296 zvol_minphys(struct buf *bp) 1297 { 1298 if (bp->b_bcount > zvol_maxphys) 1299 bp->b_bcount = zvol_maxphys; 1300 } 1301 1302 int 1303 zvol_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblocks) 1304 { 1305 minor_t minor = getminor(dev); 1306 zvol_state_t *zv; 1307 int error = 0; 1308 uint64_t size; 1309 uint64_t boff; 1310 uint64_t resid; 1311 1312 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1313 if (zv == NULL) 1314 return (SET_ERROR(ENXIO)); 1315 1316 if ((zv->zv_flags & ZVOL_DUMPIFIED) == 0) 1317 return (SET_ERROR(EINVAL)); 1318 1319 boff = ldbtob(blkno); 1320 resid = ldbtob(nblocks); 1321 1322 VERIFY3U(boff + resid, <=, zv->zv_volsize); 1323 1324 while (resid) { 1325 size = MIN(resid, P2END(boff, zv->zv_volblocksize) - boff); 1326 error = zvol_dumpio(zv, addr, boff, size, B_FALSE, B_TRUE); 1327 if (error) 1328 break; 1329 boff += size; 1330 addr += size; 1331 resid -= size; 1332 } 1333 1334 return (error); 1335 } 1336 1337 /*ARGSUSED*/ 1338 int 1339 zvol_read(dev_t dev, uio_t *uio, cred_t *cr) 1340 { 1341 minor_t minor = getminor(dev); 1342 zvol_state_t *zv; 1343 uint64_t volsize; 1344 int error = 0; 1345 1346 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1347 if (zv == NULL) 1348 return (SET_ERROR(ENXIO)); 1349 1350 volsize = zv->zv_volsize; 1351 if (uio->uio_resid > 0 && 1352 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize)) 1353 return (SET_ERROR(EIO)); 1354 1355 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1356 error = physio(zvol_strategy, NULL, dev, B_READ, 1357 zvol_minphys, uio); 1358 return (error); 1359 } 1360 1361 smt_begin_unsafe(); 1362 1363 locked_range_t *lr = rangelock_enter(&zv->zv_rangelock, 1364 uio->uio_loffset, uio->uio_resid, RL_READER); 1365 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1366 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1367 1368 /* don't read past the end */ 1369 if (bytes > volsize - uio->uio_loffset) 1370 bytes = volsize - uio->uio_loffset; 1371 1372 error = dmu_read_uio(zv->zv_objset, ZVOL_OBJ, uio, bytes); 1373 if (error) { 1374 /* convert checksum errors into IO errors */ 1375 if (error == ECKSUM) 1376 error = SET_ERROR(EIO); 1377 break; 1378 } 1379 } 1380 rangelock_exit(lr); 1381 1382 smt_end_unsafe(); 1383 1384 return (error); 1385 } 1386 1387 /*ARGSUSED*/ 1388 int 1389 zvol_write(dev_t dev, uio_t *uio, cred_t *cr) 1390 { 1391 minor_t minor = getminor(dev); 1392 zvol_state_t *zv; 1393 uint64_t volsize; 1394 int error = 0; 1395 boolean_t sync; 1396 1397 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1398 if (zv == NULL) 1399 return (SET_ERROR(ENXIO)); 1400 1401 volsize = zv->zv_volsize; 1402 if (uio->uio_resid > 0 && 1403 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize)) 1404 return (SET_ERROR(EIO)); 1405 1406 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1407 error = physio(zvol_strategy, NULL, dev, B_WRITE, 1408 zvol_minphys, uio); 1409 return (error); 1410 } 1411 1412 smt_begin_unsafe(); 1413 1414 sync = !(zv->zv_flags & ZVOL_WCE) || 1415 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS); 1416 1417 locked_range_t *lr = rangelock_enter(&zv->zv_rangelock, 1418 uio->uio_loffset, uio->uio_resid, RL_WRITER); 1419 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1420 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1421 uint64_t off = uio->uio_loffset; 1422 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset); 1423 1424 if (bytes > volsize - off) /* don't write past the end */ 1425 bytes = volsize - off; 1426 1427 dmu_tx_hold_write_by_dnode(tx, zv->zv_dn, off, bytes); 1428 error = dmu_tx_assign(tx, TXG_WAIT); 1429 if (error) { 1430 dmu_tx_abort(tx); 1431 break; 1432 } 1433 error = dmu_write_uio_dnode(zv->zv_dn, uio, bytes, tx); 1434 if (error == 0) 1435 zvol_log_write(zv, tx, off, bytes, sync); 1436 dmu_tx_commit(tx); 1437 1438 if (error) 1439 break; 1440 } 1441 rangelock_exit(lr); 1442 1443 if (sync) 1444 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1445 1446 smt_end_unsafe(); 1447 1448 return (error); 1449 } 1450 1451 int 1452 zvol_getefi(void *arg, int flag, uint64_t vs, uint8_t bs) 1453 { 1454 struct uuid uuid = EFI_RESERVED; 1455 efi_gpe_t gpe = { 0 }; 1456 uint32_t crc; 1457 dk_efi_t efi; 1458 int length; 1459 char *ptr; 1460 1461 if (ddi_copyin(arg, &efi, sizeof (dk_efi_t), flag)) 1462 return (SET_ERROR(EFAULT)); 1463 ptr = (char *)(uintptr_t)efi.dki_data_64; 1464 length = efi.dki_length; 1465 /* 1466 * Some clients may attempt to request a PMBR for the 1467 * zvol. Currently this interface will return EINVAL to 1468 * such requests. These requests could be supported by 1469 * adding a check for lba == 0 and consing up an appropriate 1470 * PMBR. 1471 */ 1472 if (efi.dki_lba < 1 || efi.dki_lba > 2 || length <= 0) 1473 return (SET_ERROR(EINVAL)); 1474 1475 gpe.efi_gpe_StartingLBA = LE_64(34ULL); 1476 gpe.efi_gpe_EndingLBA = LE_64((vs >> bs) - 1); 1477 UUID_LE_CONVERT(gpe.efi_gpe_PartitionTypeGUID, uuid); 1478 1479 if (efi.dki_lba == 1) { 1480 efi_gpt_t gpt = { 0 }; 1481 1482 gpt.efi_gpt_Signature = LE_64(EFI_SIGNATURE); 1483 gpt.efi_gpt_Revision = LE_32(EFI_VERSION_CURRENT); 1484 gpt.efi_gpt_HeaderSize = LE_32(EFI_HEADER_SIZE); 1485 gpt.efi_gpt_MyLBA = LE_64(1ULL); 1486 gpt.efi_gpt_FirstUsableLBA = LE_64(34ULL); 1487 gpt.efi_gpt_LastUsableLBA = LE_64((vs >> bs) - 1); 1488 gpt.efi_gpt_PartitionEntryLBA = LE_64(2ULL); 1489 gpt.efi_gpt_NumberOfPartitionEntries = LE_32(1); 1490 gpt.efi_gpt_SizeOfPartitionEntry = 1491 LE_32(sizeof (efi_gpe_t)); 1492 CRC32(crc, &gpe, sizeof (gpe), -1U, crc32_table); 1493 gpt.efi_gpt_PartitionEntryArrayCRC32 = LE_32(~crc); 1494 CRC32(crc, &gpt, EFI_HEADER_SIZE, -1U, crc32_table); 1495 gpt.efi_gpt_HeaderCRC32 = LE_32(~crc); 1496 if (ddi_copyout(&gpt, ptr, MIN(sizeof (gpt), length), 1497 flag)) 1498 return (SET_ERROR(EFAULT)); 1499 ptr += sizeof (gpt); 1500 length -= sizeof (gpt); 1501 } 1502 if (length > 0 && ddi_copyout(&gpe, ptr, MIN(sizeof (gpe), 1503 length), flag)) 1504 return (SET_ERROR(EFAULT)); 1505 return (0); 1506 } 1507 1508 /* 1509 * BEGIN entry points to allow external callers access to the volume. 1510 */ 1511 /* 1512 * Return the volume parameters needed for access from an external caller. 1513 * These values are invariant as long as the volume is held open. 1514 */ 1515 int 1516 zvol_get_volume_params(minor_t minor, uint64_t *blksize, 1517 uint64_t *max_xfer_len, void **minor_hdl, void **objset_hdl, void **zil_hdl, 1518 void **rl_hdl, void **dnode_hdl) 1519 { 1520 zvol_state_t *zv; 1521 1522 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1523 if (zv == NULL) 1524 return (SET_ERROR(ENXIO)); 1525 if (zv->zv_flags & ZVOL_DUMPIFIED) 1526 return (SET_ERROR(ENXIO)); 1527 1528 ASSERT(blksize && max_xfer_len && minor_hdl && 1529 objset_hdl && zil_hdl && rl_hdl && dnode_hdl); 1530 1531 *blksize = zv->zv_volblocksize; 1532 *max_xfer_len = (uint64_t)zvol_maxphys; 1533 *minor_hdl = zv; 1534 *objset_hdl = zv->zv_objset; 1535 *zil_hdl = zv->zv_zilog; 1536 *rl_hdl = &zv->zv_rangelock; 1537 *dnode_hdl = zv->zv_dn; 1538 return (0); 1539 } 1540 1541 /* 1542 * Return the current volume size to an external caller. 1543 * The size can change while the volume is open. 1544 */ 1545 uint64_t 1546 zvol_get_volume_size(void *minor_hdl) 1547 { 1548 zvol_state_t *zv = minor_hdl; 1549 1550 return (zv->zv_volsize); 1551 } 1552 1553 /* 1554 * Return the current WCE setting to an external caller. 1555 * The WCE setting can change while the volume is open. 1556 */ 1557 int 1558 zvol_get_volume_wce(void *minor_hdl) 1559 { 1560 zvol_state_t *zv = minor_hdl; 1561 1562 return ((zv->zv_flags & ZVOL_WCE) ? 1 : 0); 1563 } 1564 1565 /* 1566 * Entry point for external callers to zvol_log_write 1567 */ 1568 void 1569 zvol_log_write_minor(void *minor_hdl, dmu_tx_t *tx, offset_t off, ssize_t resid, 1570 boolean_t sync) 1571 { 1572 zvol_state_t *zv = minor_hdl; 1573 1574 zvol_log_write(zv, tx, off, resid, sync); 1575 } 1576 /* 1577 * END entry points to allow external callers access to the volume. 1578 */ 1579 1580 /* 1581 * Log a DKIOCFREE/free-long-range to the ZIL with TX_TRUNCATE. 1582 */ 1583 static void 1584 zvol_log_truncate(zvol_state_t *zv, dmu_tx_t *tx, uint64_t off, uint64_t len, 1585 boolean_t sync) 1586 { 1587 itx_t *itx; 1588 lr_truncate_t *lr; 1589 zilog_t *zilog = zv->zv_zilog; 1590 1591 if (zil_replaying(zilog, tx)) 1592 return; 1593 1594 itx = zil_itx_create(TX_TRUNCATE, sizeof (*lr)); 1595 lr = (lr_truncate_t *)&itx->itx_lr; 1596 lr->lr_foid = ZVOL_OBJ; 1597 lr->lr_offset = off; 1598 lr->lr_length = len; 1599 1600 itx->itx_sync = sync; 1601 zil_itx_assign(zilog, itx, tx); 1602 } 1603 1604 /* 1605 * Dirtbag ioctls to support mkfs(8) for UFS filesystems. See dkio(4I). 1606 * Also a dirtbag dkio ioctl for unmap/free-block functionality. 1607 */ 1608 /*ARGSUSED*/ 1609 int 1610 zvol_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp) 1611 { 1612 zvol_state_t *zv; 1613 struct dk_callback *dkc; 1614 int i, error = 0; 1615 locked_range_t *lr; 1616 1617 mutex_enter(&zfsdev_state_lock); 1618 1619 zv = zfsdev_get_soft_state(getminor(dev), ZSST_ZVOL); 1620 1621 if (zv == NULL) { 1622 mutex_exit(&zfsdev_state_lock); 1623 return (SET_ERROR(ENXIO)); 1624 } 1625 ASSERT(zv->zv_total_opens > 0); 1626 1627 switch (cmd) { 1628 1629 case DKIOCINFO: 1630 { 1631 struct dk_cinfo dki; 1632 1633 bzero(&dki, sizeof (dki)); 1634 (void) strcpy(dki.dki_cname, "zvol"); 1635 (void) strcpy(dki.dki_dname, "zvol"); 1636 dki.dki_ctype = DKC_UNKNOWN; 1637 dki.dki_unit = getminor(dev); 1638 dki.dki_maxtransfer = 1639 1 << (SPA_OLD_MAXBLOCKSHIFT - zv->zv_min_bs); 1640 mutex_exit(&zfsdev_state_lock); 1641 if (ddi_copyout(&dki, (void *)arg, sizeof (dki), flag)) 1642 error = SET_ERROR(EFAULT); 1643 return (error); 1644 } 1645 1646 case DKIOCGMEDIAINFO: 1647 { 1648 struct dk_minfo dkm; 1649 1650 bzero(&dkm, sizeof (dkm)); 1651 dkm.dki_lbsize = 1U << zv->zv_min_bs; 1652 dkm.dki_capacity = zv->zv_volsize >> zv->zv_min_bs; 1653 dkm.dki_media_type = DK_UNKNOWN; 1654 mutex_exit(&zfsdev_state_lock); 1655 if (ddi_copyout(&dkm, (void *)arg, sizeof (dkm), flag)) 1656 error = SET_ERROR(EFAULT); 1657 return (error); 1658 } 1659 1660 case DKIOCGMEDIAINFOEXT: 1661 { 1662 struct dk_minfo_ext dkmext; 1663 size_t len; 1664 1665 bzero(&dkmext, sizeof (dkmext)); 1666 dkmext.dki_lbsize = 1U << zv->zv_min_bs; 1667 dkmext.dki_pbsize = zv->zv_volblocksize; 1668 dkmext.dki_capacity = zv->zv_volsize >> zv->zv_min_bs; 1669 dkmext.dki_media_type = DK_UNKNOWN; 1670 mutex_exit(&zfsdev_state_lock); 1671 1672 switch (ddi_model_convert_from(flag & FMODELS)) { 1673 case DDI_MODEL_ILP32: 1674 len = sizeof (struct dk_minfo_ext32); 1675 break; 1676 default: 1677 len = sizeof (struct dk_minfo_ext); 1678 break; 1679 } 1680 1681 if (ddi_copyout(&dkmext, (void *)arg, len, flag)) 1682 error = SET_ERROR(EFAULT); 1683 return (error); 1684 } 1685 1686 case DKIOCGETEFI: 1687 { 1688 uint64_t vs = zv->zv_volsize; 1689 uint8_t bs = zv->zv_min_bs; 1690 1691 mutex_exit(&zfsdev_state_lock); 1692 error = zvol_getefi((void *)arg, flag, vs, bs); 1693 return (error); 1694 } 1695 1696 case DKIOCFLUSHWRITECACHE: 1697 dkc = (struct dk_callback *)arg; 1698 mutex_exit(&zfsdev_state_lock); 1699 1700 smt_begin_unsafe(); 1701 1702 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1703 if ((flag & FKIOCTL) && dkc != NULL && dkc->dkc_callback) { 1704 (*dkc->dkc_callback)(dkc->dkc_cookie, error); 1705 error = 0; 1706 } 1707 1708 smt_end_unsafe(); 1709 1710 return (error); 1711 1712 case DKIOCGETWCE: 1713 { 1714 int wce = (zv->zv_flags & ZVOL_WCE) ? 1 : 0; 1715 if (ddi_copyout(&wce, (void *)arg, sizeof (int), 1716 flag)) 1717 error = SET_ERROR(EFAULT); 1718 break; 1719 } 1720 case DKIOCSETWCE: 1721 { 1722 int wce; 1723 if (ddi_copyin((void *)arg, &wce, sizeof (int), 1724 flag)) { 1725 error = SET_ERROR(EFAULT); 1726 break; 1727 } 1728 if (wce) { 1729 zv->zv_flags |= ZVOL_WCE; 1730 mutex_exit(&zfsdev_state_lock); 1731 } else { 1732 zv->zv_flags &= ~ZVOL_WCE; 1733 mutex_exit(&zfsdev_state_lock); 1734 smt_begin_unsafe(); 1735 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1736 smt_end_unsafe(); 1737 } 1738 return (0); 1739 } 1740 1741 case DKIOCGGEOM: 1742 case DKIOCGVTOC: 1743 /* 1744 * commands using these (like prtvtoc) expect ENOTSUP 1745 * since we're emulating an EFI label 1746 */ 1747 error = SET_ERROR(ENOTSUP); 1748 break; 1749 1750 case DKIOCDUMPINIT: 1751 lr = rangelock_enter(&zv->zv_rangelock, 0, zv->zv_volsize, 1752 RL_WRITER); 1753 error = zvol_dumpify(zv); 1754 rangelock_exit(lr); 1755 break; 1756 1757 case DKIOCDUMPFINI: 1758 if (!(zv->zv_flags & ZVOL_DUMPIFIED)) 1759 break; 1760 lr = rangelock_enter(&zv->zv_rangelock, 0, zv->zv_volsize, 1761 RL_WRITER); 1762 error = zvol_dump_fini(zv); 1763 rangelock_exit(lr); 1764 break; 1765 1766 case DKIOCFREE: 1767 { 1768 dkioc_free_list_t *dfl; 1769 dmu_tx_t *tx; 1770 1771 if (!zvol_unmap_enabled) 1772 break; 1773 1774 if (!(flag & FKIOCTL)) { 1775 error = dfl_copyin((void *)arg, &dfl, flag, KM_SLEEP); 1776 if (error != 0) 1777 break; 1778 } else { 1779 dfl = (dkioc_free_list_t *)arg; 1780 ASSERT3U(dfl->dfl_num_exts, <=, DFL_COPYIN_MAX_EXTS); 1781 if (dfl->dfl_num_exts > DFL_COPYIN_MAX_EXTS) { 1782 error = SET_ERROR(EINVAL); 1783 break; 1784 } 1785 } 1786 1787 mutex_exit(&zfsdev_state_lock); 1788 1789 smt_begin_unsafe(); 1790 1791 for (int i = 0; i < dfl->dfl_num_exts; i++) { 1792 uint64_t start = dfl->dfl_exts[i].dfle_start, 1793 length = dfl->dfl_exts[i].dfle_length, 1794 end = start + length; 1795 1796 /* 1797 * Apply Postel's Law to length-checking. If they 1798 * overshoot, just blank out until the end, if there's 1799 * a need to blank out anything. 1800 */ 1801 if (start >= zv->zv_volsize) 1802 continue; /* No need to do anything... */ 1803 if (end > zv->zv_volsize) { 1804 end = DMU_OBJECT_END; 1805 length = end - start; 1806 } 1807 1808 lr = rangelock_enter(&zv->zv_rangelock, start, length, 1809 RL_WRITER); 1810 tx = dmu_tx_create(zv->zv_objset); 1811 error = dmu_tx_assign(tx, TXG_WAIT); 1812 if (error != 0) { 1813 dmu_tx_abort(tx); 1814 } else { 1815 zvol_log_truncate(zv, tx, start, length, 1816 B_TRUE); 1817 dmu_tx_commit(tx); 1818 error = dmu_free_long_range(zv->zv_objset, 1819 ZVOL_OBJ, start, length); 1820 } 1821 1822 rangelock_exit(lr); 1823 1824 if (error != 0) 1825 break; 1826 } 1827 1828 /* 1829 * If the write-cache is disabled, 'sync' property 1830 * is set to 'always', or if the caller is asking for 1831 * a synchronous free, commit this operation to the zil. 1832 * This will sync any previous uncommitted writes to the 1833 * zvol object. 1834 * Can be overridden by the zvol_unmap_sync_enabled tunable. 1835 */ 1836 if ((error == 0) && zvol_unmap_sync_enabled && 1837 (!(zv->zv_flags & ZVOL_WCE) || 1838 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS) || 1839 (dfl->dfl_flags & DF_WAIT_SYNC))) { 1840 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1841 } 1842 1843 if (!(flag & FKIOCTL)) 1844 dfl_free(dfl); 1845 1846 smt_end_unsafe(); 1847 1848 return (error); 1849 } 1850 1851 case DKIOC_CANFREE: 1852 i = zvol_unmap_enabled ? 1 : 0; 1853 if (ddi_copyout(&i, (void *)arg, sizeof (int), flag) != 0) { 1854 error = EFAULT; 1855 } else { 1856 error = 0; 1857 } 1858 break; 1859 1860 default: 1861 error = SET_ERROR(ENOTTY); 1862 break; 1863 1864 } 1865 mutex_exit(&zfsdev_state_lock); 1866 return (error); 1867 } 1868 1869 int 1870 zvol_busy(void) 1871 { 1872 return (zvol_minors != 0); 1873 } 1874 1875 void 1876 zvol_init(void) 1877 { 1878 VERIFY(ddi_soft_state_init(&zfsdev_state, sizeof (zfs_soft_state_t), 1879 1) == 0); 1880 mutex_init(&zfsdev_state_lock, NULL, MUTEX_DEFAULT, NULL); 1881 } 1882 1883 void 1884 zvol_fini(void) 1885 { 1886 mutex_destroy(&zfsdev_state_lock); 1887 ddi_soft_state_fini(&zfsdev_state); 1888 } 1889 1890 /*ARGSUSED*/ 1891 static int 1892 zfs_mvdev_dump_feature_check(void *arg, dmu_tx_t *tx) 1893 { 1894 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 1895 1896 if (spa_feature_is_active(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP)) 1897 return (1); 1898 return (0); 1899 } 1900 1901 /*ARGSUSED*/ 1902 static void 1903 zfs_mvdev_dump_activate_feature_sync(void *arg, dmu_tx_t *tx) 1904 { 1905 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 1906 1907 spa_feature_incr(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP, tx); 1908 } 1909 1910 static int 1911 zvol_dump_init(zvol_state_t *zv, boolean_t resize) 1912 { 1913 dmu_tx_t *tx; 1914 int error; 1915 objset_t *os = zv->zv_objset; 1916 spa_t *spa = dmu_objset_spa(os); 1917 vdev_t *vd = spa->spa_root_vdev; 1918 nvlist_t *nv = NULL; 1919 uint64_t version = spa_version(spa); 1920 uint64_t checksum, compress, refresrv, vbs, dedup; 1921 1922 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 1923 ASSERT(vd->vdev_ops == &vdev_root_ops); 1924 1925 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 0, 1926 DMU_OBJECT_END); 1927 if (error != 0) 1928 return (error); 1929 /* wait for dmu_free_long_range to actually free the blocks */ 1930 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 1931 1932 /* 1933 * If the pool on which the dump device is being initialized has more 1934 * than one child vdev, check that the MULTI_VDEV_CRASH_DUMP feature is 1935 * enabled. If so, bump that feature's counter to indicate that the 1936 * feature is active. We also check the vdev type to handle the 1937 * following case: 1938 * # zpool create test raidz disk1 disk2 disk3 1939 * Now have spa_root_vdev->vdev_children == 1 (the raidz vdev), 1940 * the raidz vdev itself has 3 children. 1941 */ 1942 if (vd->vdev_children > 1 || vd->vdev_ops == &vdev_raidz_ops) { 1943 if (!spa_feature_is_enabled(spa, 1944 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP)) 1945 return (SET_ERROR(ENOTSUP)); 1946 (void) dsl_sync_task(spa_name(spa), 1947 zfs_mvdev_dump_feature_check, 1948 zfs_mvdev_dump_activate_feature_sync, NULL, 1949 2, ZFS_SPACE_CHECK_RESERVED); 1950 } 1951 1952 if (!resize) { 1953 error = dsl_prop_get_integer(zv->zv_name, 1954 zfs_prop_to_name(ZFS_PROP_COMPRESSION), &compress, NULL); 1955 if (error == 0) { 1956 error = dsl_prop_get_integer(zv->zv_name, 1957 zfs_prop_to_name(ZFS_PROP_CHECKSUM), &checksum, 1958 NULL); 1959 } 1960 if (error == 0) { 1961 error = dsl_prop_get_integer(zv->zv_name, 1962 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 1963 &refresrv, NULL); 1964 } 1965 if (error == 0) { 1966 error = dsl_prop_get_integer(zv->zv_name, 1967 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &vbs, 1968 NULL); 1969 } 1970 if (version >= SPA_VERSION_DEDUP && error == 0) { 1971 error = dsl_prop_get_integer(zv->zv_name, 1972 zfs_prop_to_name(ZFS_PROP_DEDUP), &dedup, NULL); 1973 } 1974 } 1975 if (error != 0) 1976 return (error); 1977 1978 tx = dmu_tx_create(os); 1979 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 1980 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 1981 error = dmu_tx_assign(tx, TXG_WAIT); 1982 if (error != 0) { 1983 dmu_tx_abort(tx); 1984 return (error); 1985 } 1986 1987 /* 1988 * If we are resizing the dump device then we only need to 1989 * update the refreservation to match the newly updated 1990 * zvolsize. Otherwise, we save off the original state of the 1991 * zvol so that we can restore them if the zvol is ever undumpified. 1992 */ 1993 if (resize) { 1994 error = zap_update(os, ZVOL_ZAP_OBJ, 1995 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 1996 &zv->zv_volsize, tx); 1997 } else { 1998 error = zap_update(os, ZVOL_ZAP_OBJ, 1999 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, 2000 &compress, tx); 2001 if (error == 0) { 2002 error = zap_update(os, ZVOL_ZAP_OBJ, 2003 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, 2004 &checksum, tx); 2005 } 2006 if (error == 0) { 2007 error = zap_update(os, ZVOL_ZAP_OBJ, 2008 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 2009 &refresrv, tx); 2010 } 2011 if (error == 0) { 2012 error = zap_update(os, ZVOL_ZAP_OBJ, 2013 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, 2014 &vbs, tx); 2015 } 2016 if (error == 0) { 2017 error = dmu_object_set_blocksize( 2018 os, ZVOL_OBJ, SPA_OLD_MAXBLOCKSIZE, 0, tx); 2019 } 2020 if (version >= SPA_VERSION_DEDUP && error == 0) { 2021 error = zap_update(os, ZVOL_ZAP_OBJ, 2022 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, 2023 &dedup, tx); 2024 } 2025 if (error == 0) 2026 zv->zv_volblocksize = SPA_OLD_MAXBLOCKSIZE; 2027 } 2028 dmu_tx_commit(tx); 2029 2030 /* 2031 * We only need update the zvol's property if we are initializing 2032 * the dump area for the first time. 2033 */ 2034 if (error == 0 && !resize) { 2035 /* 2036 * If MULTI_VDEV_CRASH_DUMP is active, use the NOPARITY checksum 2037 * function. Otherwise, use the old default -- OFF. 2038 */ 2039 checksum = spa_feature_is_active(spa, 2040 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP) ? ZIO_CHECKSUM_NOPARITY : 2041 ZIO_CHECKSUM_OFF; 2042 2043 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 2044 VERIFY(nvlist_add_uint64(nv, 2045 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 0) == 0); 2046 VERIFY(nvlist_add_uint64(nv, 2047 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 2048 ZIO_COMPRESS_OFF) == 0); 2049 VERIFY(nvlist_add_uint64(nv, 2050 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 2051 checksum) == 0); 2052 if (version >= SPA_VERSION_DEDUP) { 2053 VERIFY(nvlist_add_uint64(nv, 2054 zfs_prop_to_name(ZFS_PROP_DEDUP), 2055 ZIO_CHECKSUM_OFF) == 0); 2056 } 2057 2058 error = zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL, 2059 nv, NULL); 2060 nvlist_free(nv); 2061 } 2062 2063 /* Allocate the space for the dump */ 2064 if (error == 0) 2065 error = zvol_prealloc(zv); 2066 return (error); 2067 } 2068 2069 static int 2070 zvol_dumpify(zvol_state_t *zv) 2071 { 2072 int error = 0; 2073 uint64_t dumpsize = 0; 2074 dmu_tx_t *tx; 2075 objset_t *os = zv->zv_objset; 2076 2077 if (zv->zv_flags & ZVOL_RDONLY) 2078 return (SET_ERROR(EROFS)); 2079 2080 if (os->os_encrypted) 2081 return (SET_ERROR(ENOTSUP)); 2082 2083 if (zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 2084 8, 1, &dumpsize) != 0 || dumpsize != zv->zv_volsize) { 2085 boolean_t resize = (dumpsize > 0); 2086 2087 if ((error = zvol_dump_init(zv, resize)) != 0) { 2088 (void) zvol_dump_fini(zv); 2089 return (error); 2090 } 2091 } 2092 2093 /* 2094 * Build up our lba mapping. 2095 */ 2096 error = zvol_get_lbas(zv); 2097 if (error) { 2098 (void) zvol_dump_fini(zv); 2099 return (error); 2100 } 2101 2102 tx = dmu_tx_create(os); 2103 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 2104 error = dmu_tx_assign(tx, TXG_WAIT); 2105 if (error) { 2106 dmu_tx_abort(tx); 2107 (void) zvol_dump_fini(zv); 2108 return (error); 2109 } 2110 2111 zv->zv_flags |= ZVOL_DUMPIFIED; 2112 error = zap_update(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 8, 1, 2113 &zv->zv_volsize, tx); 2114 dmu_tx_commit(tx); 2115 2116 if (error) { 2117 (void) zvol_dump_fini(zv); 2118 return (error); 2119 } 2120 2121 txg_wait_synced(dmu_objset_pool(os), 0); 2122 return (0); 2123 } 2124 2125 static int 2126 zvol_dump_fini(zvol_state_t *zv) 2127 { 2128 dmu_tx_t *tx; 2129 objset_t *os = zv->zv_objset; 2130 nvlist_t *nv; 2131 int error = 0; 2132 uint64_t checksum, compress, refresrv, vbs, dedup; 2133 uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset)); 2134 2135 /* 2136 * Attempt to restore the zvol back to its pre-dumpified state. 2137 * This is a best-effort attempt as it's possible that not all 2138 * of these properties were initialized during the dumpify process 2139 * (i.e. error during zvol_dump_init). 2140 */ 2141 2142 tx = dmu_tx_create(os); 2143 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 2144 error = dmu_tx_assign(tx, TXG_WAIT); 2145 if (error) { 2146 dmu_tx_abort(tx); 2147 return (error); 2148 } 2149 (void) zap_remove(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, tx); 2150 dmu_tx_commit(tx); 2151 2152 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2153 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum); 2154 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2155 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, &compress); 2156 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2157 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, &refresrv); 2158 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2159 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, &vbs); 2160 2161 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 2162 (void) nvlist_add_uint64(nv, 2163 zfs_prop_to_name(ZFS_PROP_CHECKSUM), checksum); 2164 (void) nvlist_add_uint64(nv, 2165 zfs_prop_to_name(ZFS_PROP_COMPRESSION), compress); 2166 (void) nvlist_add_uint64(nv, 2167 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), refresrv); 2168 if (version >= SPA_VERSION_DEDUP && 2169 zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2170 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, &dedup) == 0) { 2171 (void) nvlist_add_uint64(nv, 2172 zfs_prop_to_name(ZFS_PROP_DEDUP), dedup); 2173 } 2174 (void) zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL, 2175 nv, NULL); 2176 nvlist_free(nv); 2177 2178 zvol_free_extents(zv); 2179 zv->zv_flags &= ~ZVOL_DUMPIFIED; 2180 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, DMU_OBJECT_END); 2181 /* wait for dmu_free_long_range to actually free the blocks */ 2182 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 2183 tx = dmu_tx_create(os); 2184 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 2185 error = dmu_tx_assign(tx, TXG_WAIT); 2186 if (error) { 2187 dmu_tx_abort(tx); 2188 return (error); 2189 } 2190 if (dmu_object_set_blocksize(os, ZVOL_OBJ, vbs, 0, tx) == 0) 2191 zv->zv_volblocksize = vbs; 2192 dmu_tx_commit(tx); 2193 2194 return (0); 2195 } 2196