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 sysevent_id_t eid; 817 nvlist_t *attr; 818 char *physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 819 820 (void) snprintf(physpath, MAXPATHLEN, "%s%u", ZVOL_PSEUDO_DEV, 821 zv->zv_minor); 822 823 VERIFY(nvlist_alloc(&attr, NV_UNIQUE_NAME, KM_SLEEP) == 0); 824 VERIFY(nvlist_add_string(attr, DEV_PHYS_PATH, physpath) == 0); 825 826 (void) ddi_log_sysevent(zfs_dip, SUNW_VENDOR, EC_DEV_STATUS, 827 ESC_DEV_DLE, attr, &eid, DDI_SLEEP); 828 829 nvlist_free(attr); 830 kmem_free(physpath, MAXPATHLEN); 831 } 832 return (error); 833 } 834 835 int 836 zvol_set_volsize(const char *name, uint64_t volsize) 837 { 838 zvol_state_t *zv = NULL; 839 objset_t *os; 840 int error; 841 dmu_object_info_t doi; 842 uint64_t readonly; 843 boolean_t owned = B_FALSE; 844 845 error = dsl_prop_get_integer(name, 846 zfs_prop_to_name(ZFS_PROP_READONLY), &readonly, NULL); 847 if (error != 0) 848 return (error); 849 if (readonly) 850 return (SET_ERROR(EROFS)); 851 852 mutex_enter(&zfsdev_state_lock); 853 zv = zvol_minor_lookup(name); 854 855 if (zv == NULL || zv->zv_objset == NULL) { 856 if ((error = dmu_objset_own(name, DMU_OST_ZVOL, B_FALSE, B_TRUE, 857 FTAG, &os)) != 0) { 858 mutex_exit(&zfsdev_state_lock); 859 return (error); 860 } 861 owned = B_TRUE; 862 if (zv != NULL) 863 zv->zv_objset = os; 864 } else { 865 os = zv->zv_objset; 866 } 867 868 if ((error = dmu_object_info(os, ZVOL_OBJ, &doi)) != 0 || 869 (error = zvol_check_volsize(volsize, doi.doi_data_block_size)) != 0) 870 goto out; 871 872 error = zvol_update_volsize(os, volsize); 873 874 if (error == 0 && zv != NULL) 875 error = zvol_update_live_volsize(zv, volsize); 876 out: 877 if (owned) { 878 dmu_objset_disown(os, B_TRUE, FTAG); 879 if (zv != NULL) 880 zv->zv_objset = NULL; 881 } 882 mutex_exit(&zfsdev_state_lock); 883 return (error); 884 } 885 886 /*ARGSUSED*/ 887 int 888 zvol_open(dev_t *devp, int flag, int otyp, cred_t *cr) 889 { 890 zvol_state_t *zv; 891 int err = 0; 892 893 mutex_enter(&zfsdev_state_lock); 894 895 zv = zfsdev_get_soft_state(getminor(*devp), ZSST_ZVOL); 896 if (zv == NULL) { 897 mutex_exit(&zfsdev_state_lock); 898 return (SET_ERROR(ENXIO)); 899 } 900 901 if (zv->zv_total_opens == 0) 902 err = zvol_first_open(zv, !(flag & FWRITE)); 903 if (err) { 904 mutex_exit(&zfsdev_state_lock); 905 return (err); 906 } 907 908 if ((flag & FWRITE) && (zv->zv_flags & ZVOL_RDONLY)) { 909 err = SET_ERROR(EROFS); 910 goto out; 911 } 912 if (zv->zv_flags & ZVOL_EXCL) { 913 err = SET_ERROR(EBUSY); 914 goto out; 915 } 916 if (flag & FEXCL) { 917 if (zv->zv_total_opens != 0) { 918 err = SET_ERROR(EBUSY); 919 goto out; 920 } 921 zv->zv_flags |= ZVOL_EXCL; 922 } 923 924 if (zv->zv_open_count[otyp] == 0 || otyp == OTYP_LYR) { 925 zv->zv_open_count[otyp]++; 926 zv->zv_total_opens++; 927 } 928 mutex_exit(&zfsdev_state_lock); 929 930 return (err); 931 out: 932 if (zv->zv_total_opens == 0) 933 zvol_last_close(zv); 934 mutex_exit(&zfsdev_state_lock); 935 return (err); 936 } 937 938 /*ARGSUSED*/ 939 int 940 zvol_close(dev_t dev, int flag, int otyp, cred_t *cr) 941 { 942 minor_t minor = getminor(dev); 943 zvol_state_t *zv; 944 int error = 0; 945 946 mutex_enter(&zfsdev_state_lock); 947 948 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 949 if (zv == NULL) { 950 mutex_exit(&zfsdev_state_lock); 951 return (SET_ERROR(ENXIO)); 952 } 953 954 if (zv->zv_flags & ZVOL_EXCL) { 955 ASSERT(zv->zv_total_opens == 1); 956 zv->zv_flags &= ~ZVOL_EXCL; 957 } 958 959 /* 960 * If the open count is zero, this is a spurious close. 961 * That indicates a bug in the kernel / DDI framework. 962 */ 963 ASSERT(zv->zv_open_count[otyp] != 0); 964 ASSERT(zv->zv_total_opens != 0); 965 966 /* 967 * You may get multiple opens, but only one close. 968 */ 969 zv->zv_open_count[otyp]--; 970 zv->zv_total_opens--; 971 972 if (zv->zv_total_opens == 0) 973 zvol_last_close(zv); 974 975 mutex_exit(&zfsdev_state_lock); 976 return (error); 977 } 978 979 /* ARGSUSED */ 980 static void 981 zvol_get_done(zgd_t *zgd, int error) 982 { 983 if (zgd->zgd_db) 984 dmu_buf_rele(zgd->zgd_db, zgd); 985 986 rangelock_exit(zgd->zgd_lr); 987 988 kmem_free(zgd, sizeof (zgd_t)); 989 } 990 991 /* 992 * Get data to generate a TX_WRITE intent log record. 993 */ 994 static int 995 zvol_get_data(void *arg, lr_write_t *lr, char *buf, struct lwb *lwb, zio_t *zio) 996 { 997 zvol_state_t *zv = arg; 998 uint64_t offset = lr->lr_offset; 999 uint64_t size = lr->lr_length; /* length of user data */ 1000 dmu_buf_t *db; 1001 zgd_t *zgd; 1002 int error; 1003 1004 ASSERT3P(lwb, !=, NULL); 1005 ASSERT3P(zio, !=, NULL); 1006 ASSERT3U(size, !=, 0); 1007 1008 zgd = kmem_zalloc(sizeof (zgd_t), KM_SLEEP); 1009 zgd->zgd_lwb = lwb; 1010 1011 /* 1012 * Write records come in two flavors: immediate and indirect. 1013 * For small writes it's cheaper to store the data with the 1014 * log record (immediate); for large writes it's cheaper to 1015 * sync the data and get a pointer to it (indirect) so that 1016 * we don't have to write the data twice. 1017 */ 1018 if (buf != NULL) { /* immediate write */ 1019 zgd->zgd_lr = rangelock_enter(&zv->zv_rangelock, offset, size, 1020 RL_READER); 1021 error = dmu_read_by_dnode(zv->zv_dn, offset, size, buf, 1022 DMU_READ_NO_PREFETCH); 1023 } else { /* indirect write */ 1024 /* 1025 * Have to lock the whole block to ensure when it's written out 1026 * and its checksum is being calculated that no one can change 1027 * the data. Contrarily to zfs_get_data we need not re-check 1028 * blocksize after we get the lock because it cannot be changed. 1029 */ 1030 size = zv->zv_volblocksize; 1031 offset = P2ALIGN(offset, size); 1032 zgd->zgd_lr = rangelock_enter(&zv->zv_rangelock, offset, size, 1033 RL_READER); 1034 error = dmu_buf_hold_by_dnode(zv->zv_dn, offset, zgd, &db, 1035 DMU_READ_NO_PREFETCH); 1036 if (error == 0) { 1037 blkptr_t *bp = &lr->lr_blkptr; 1038 1039 zgd->zgd_db = db; 1040 zgd->zgd_bp = bp; 1041 1042 ASSERT(db->db_offset == offset); 1043 ASSERT(db->db_size == size); 1044 1045 error = dmu_sync(zio, lr->lr_common.lrc_txg, 1046 zvol_get_done, zgd); 1047 1048 if (error == 0) 1049 return (0); 1050 } 1051 } 1052 1053 zvol_get_done(zgd, error); 1054 1055 return (error); 1056 } 1057 1058 /* 1059 * zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions. 1060 * 1061 * We store data in the log buffers if it's small enough. 1062 * Otherwise we will later flush the data out via dmu_sync(). 1063 */ 1064 ssize_t zvol_immediate_write_sz = 32768; 1065 1066 static void 1067 zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, offset_t off, ssize_t resid, 1068 boolean_t sync) 1069 { 1070 uint32_t blocksize = zv->zv_volblocksize; 1071 zilog_t *zilog = zv->zv_zilog; 1072 itx_wr_state_t write_state; 1073 1074 if (zil_replaying(zilog, tx)) 1075 return; 1076 1077 if (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT) 1078 write_state = WR_INDIRECT; 1079 else if (!spa_has_slogs(zilog->zl_spa) && 1080 resid >= blocksize && blocksize > zvol_immediate_write_sz) 1081 write_state = WR_INDIRECT; 1082 else if (sync) 1083 write_state = WR_COPIED; 1084 else 1085 write_state = WR_NEED_COPY; 1086 1087 while (resid) { 1088 itx_t *itx; 1089 lr_write_t *lr; 1090 itx_wr_state_t wr_state = write_state; 1091 ssize_t len = resid; 1092 1093 if (wr_state == WR_COPIED && resid > ZIL_MAX_COPIED_DATA) 1094 wr_state = WR_NEED_COPY; 1095 else if (wr_state == WR_INDIRECT) 1096 len = MIN(blocksize - P2PHASE(off, blocksize), resid); 1097 1098 itx = zil_itx_create(TX_WRITE, sizeof (*lr) + 1099 (wr_state == WR_COPIED ? len : 0)); 1100 lr = (lr_write_t *)&itx->itx_lr; 1101 if (wr_state == WR_COPIED && dmu_read_by_dnode(zv->zv_dn, 1102 off, len, lr + 1, DMU_READ_NO_PREFETCH) != 0) { 1103 zil_itx_destroy(itx); 1104 itx = zil_itx_create(TX_WRITE, sizeof (*lr)); 1105 lr = (lr_write_t *)&itx->itx_lr; 1106 wr_state = WR_NEED_COPY; 1107 } 1108 1109 itx->itx_wr_state = wr_state; 1110 lr->lr_foid = ZVOL_OBJ; 1111 lr->lr_offset = off; 1112 lr->lr_length = len; 1113 lr->lr_blkoff = 0; 1114 BP_ZERO(&lr->lr_blkptr); 1115 1116 itx->itx_private = zv; 1117 itx->itx_sync = sync; 1118 1119 zil_itx_assign(zilog, itx, tx); 1120 1121 off += len; 1122 resid -= len; 1123 } 1124 } 1125 1126 static int 1127 zvol_dumpio_vdev(vdev_t *vd, void *addr, uint64_t offset, uint64_t origoffset, 1128 uint64_t size, boolean_t doread, boolean_t isdump) 1129 { 1130 if (doread && !vdev_readable(vd)) 1131 return (SET_ERROR(EIO)); 1132 if (!doread && !vdev_writeable(vd)) 1133 return (SET_ERROR(EIO)); 1134 if (vd->vdev_ops->vdev_op_dumpio == NULL) 1135 return (SET_ERROR(EIO)); 1136 1137 return (vd->vdev_ops->vdev_op_dumpio(vd, addr, size, 1138 offset, origoffset, doread, isdump)); 1139 } 1140 1141 static int 1142 zvol_dumpio(zvol_state_t *zv, void *addr, uint64_t offset, uint64_t size, 1143 boolean_t doread, boolean_t isdump) 1144 { 1145 vdev_t *vd; 1146 int error; 1147 zvol_extent_t *ze; 1148 spa_t *spa = dmu_objset_spa(zv->zv_objset); 1149 1150 /* Must be sector aligned, and not stradle a block boundary. */ 1151 if (P2PHASE(offset, DEV_BSIZE) || P2PHASE(size, DEV_BSIZE) || 1152 P2BOUNDARY(offset, size, zv->zv_volblocksize)) { 1153 return (SET_ERROR(EINVAL)); 1154 } 1155 ASSERT(size <= zv->zv_volblocksize); 1156 1157 /* Locate the extent this belongs to */ 1158 ze = list_head(&zv->zv_extents); 1159 while (offset >= ze->ze_nblks * zv->zv_volblocksize) { 1160 offset -= ze->ze_nblks * zv->zv_volblocksize; 1161 ze = list_next(&zv->zv_extents, ze); 1162 } 1163 1164 if (ze == NULL) 1165 return (SET_ERROR(EINVAL)); 1166 1167 if (!ddi_in_panic()) 1168 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER); 1169 1170 vd = vdev_lookup_top(spa, DVA_GET_VDEV(&ze->ze_dva)); 1171 offset += DVA_GET_OFFSET(&ze->ze_dva); 1172 error = zvol_dumpio_vdev(vd, addr, offset, DVA_GET_OFFSET(&ze->ze_dva), 1173 size, doread, isdump); 1174 1175 if (!ddi_in_panic()) 1176 spa_config_exit(spa, SCL_STATE, FTAG); 1177 1178 return (error); 1179 } 1180 1181 int 1182 zvol_strategy(buf_t *bp) 1183 { 1184 zfs_soft_state_t *zs = NULL; 1185 zvol_state_t *zv; 1186 uint64_t off, volsize; 1187 size_t resid; 1188 char *addr; 1189 objset_t *os; 1190 int error = 0; 1191 boolean_t doread = !!(bp->b_flags & B_READ); 1192 boolean_t is_dumpified; 1193 boolean_t sync; 1194 1195 if (getminor(bp->b_edev) == 0) { 1196 error = SET_ERROR(EINVAL); 1197 } else { 1198 zs = ddi_get_soft_state(zfsdev_state, getminor(bp->b_edev)); 1199 if (zs == NULL) 1200 error = SET_ERROR(ENXIO); 1201 else if (zs->zss_type != ZSST_ZVOL) 1202 error = SET_ERROR(EINVAL); 1203 } 1204 1205 if (error) { 1206 bioerror(bp, error); 1207 biodone(bp); 1208 return (0); 1209 } 1210 1211 zv = zs->zss_data; 1212 1213 if (!(bp->b_flags & B_READ) && (zv->zv_flags & ZVOL_RDONLY)) { 1214 bioerror(bp, EROFS); 1215 biodone(bp); 1216 return (0); 1217 } 1218 1219 off = ldbtob(bp->b_blkno); 1220 volsize = zv->zv_volsize; 1221 1222 os = zv->zv_objset; 1223 ASSERT(os != NULL); 1224 1225 bp_mapin(bp); 1226 addr = bp->b_un.b_addr; 1227 resid = bp->b_bcount; 1228 1229 if (resid > 0 && (off < 0 || off >= volsize)) { 1230 bioerror(bp, EIO); 1231 biodone(bp); 1232 return (0); 1233 } 1234 1235 is_dumpified = zv->zv_flags & ZVOL_DUMPIFIED; 1236 sync = ((!(bp->b_flags & B_ASYNC) && 1237 !(zv->zv_flags & ZVOL_WCE)) || 1238 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)) && 1239 !doread && !is_dumpified; 1240 1241 smt_begin_unsafe(); 1242 1243 /* 1244 * There must be no buffer changes when doing a dmu_sync() because 1245 * we can't change the data whilst calculating the checksum. 1246 */ 1247 locked_range_t *lr = rangelock_enter(&zv->zv_rangelock, off, resid, 1248 doread ? RL_READER : RL_WRITER); 1249 1250 while (resid != 0 && off < volsize) { 1251 size_t size = MIN(resid, zvol_maxphys); 1252 if (is_dumpified) { 1253 size = MIN(size, P2END(off, zv->zv_volblocksize) - off); 1254 error = zvol_dumpio(zv, addr, off, size, 1255 doread, B_FALSE); 1256 } else if (doread) { 1257 error = dmu_read(os, ZVOL_OBJ, off, size, addr, 1258 DMU_READ_PREFETCH); 1259 } else { 1260 dmu_tx_t *tx = dmu_tx_create(os); 1261 dmu_tx_hold_write(tx, ZVOL_OBJ, off, size); 1262 error = dmu_tx_assign(tx, TXG_WAIT); 1263 if (error) { 1264 dmu_tx_abort(tx); 1265 } else { 1266 dmu_write(os, ZVOL_OBJ, off, size, addr, tx); 1267 zvol_log_write(zv, tx, off, size, sync); 1268 dmu_tx_commit(tx); 1269 } 1270 } 1271 if (error) { 1272 /* convert checksum errors into IO errors */ 1273 if (error == ECKSUM) 1274 error = SET_ERROR(EIO); 1275 break; 1276 } 1277 off += size; 1278 addr += size; 1279 resid -= size; 1280 } 1281 rangelock_exit(lr); 1282 1283 if ((bp->b_resid = resid) == bp->b_bcount) 1284 bioerror(bp, off > volsize ? EINVAL : error); 1285 1286 if (sync) 1287 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1288 biodone(bp); 1289 1290 smt_end_unsafe(); 1291 1292 return (0); 1293 } 1294 1295 /* 1296 * Set the buffer count to the zvol maximum transfer. 1297 * Using our own routine instead of the default minphys() 1298 * means that for larger writes we write bigger buffers on X86 1299 * (128K instead of 56K) and flush the disk write cache less often 1300 * (every zvol_maxphys - currently 1MB) instead of minphys (currently 1301 * 56K on X86 and 128K on sparc). 1302 */ 1303 void 1304 zvol_minphys(struct buf *bp) 1305 { 1306 if (bp->b_bcount > zvol_maxphys) 1307 bp->b_bcount = zvol_maxphys; 1308 } 1309 1310 int 1311 zvol_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblocks) 1312 { 1313 minor_t minor = getminor(dev); 1314 zvol_state_t *zv; 1315 int error = 0; 1316 uint64_t size; 1317 uint64_t boff; 1318 uint64_t resid; 1319 1320 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1321 if (zv == NULL) 1322 return (SET_ERROR(ENXIO)); 1323 1324 if ((zv->zv_flags & ZVOL_DUMPIFIED) == 0) 1325 return (SET_ERROR(EINVAL)); 1326 1327 boff = ldbtob(blkno); 1328 resid = ldbtob(nblocks); 1329 1330 VERIFY3U(boff + resid, <=, zv->zv_volsize); 1331 1332 while (resid) { 1333 size = MIN(resid, P2END(boff, zv->zv_volblocksize) - boff); 1334 error = zvol_dumpio(zv, addr, boff, size, B_FALSE, B_TRUE); 1335 if (error) 1336 break; 1337 boff += size; 1338 addr += size; 1339 resid -= size; 1340 } 1341 1342 return (error); 1343 } 1344 1345 /*ARGSUSED*/ 1346 int 1347 zvol_read(dev_t dev, uio_t *uio, cred_t *cr) 1348 { 1349 minor_t minor = getminor(dev); 1350 zvol_state_t *zv; 1351 uint64_t volsize; 1352 int error = 0; 1353 1354 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1355 if (zv == NULL) 1356 return (SET_ERROR(ENXIO)); 1357 1358 volsize = zv->zv_volsize; 1359 if (uio->uio_resid > 0 && 1360 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize)) 1361 return (SET_ERROR(EIO)); 1362 1363 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1364 error = physio(zvol_strategy, NULL, dev, B_READ, 1365 zvol_minphys, uio); 1366 return (error); 1367 } 1368 1369 smt_begin_unsafe(); 1370 1371 locked_range_t *lr = rangelock_enter(&zv->zv_rangelock, 1372 uio->uio_loffset, uio->uio_resid, RL_READER); 1373 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1374 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1375 1376 /* don't read past the end */ 1377 if (bytes > volsize - uio->uio_loffset) 1378 bytes = volsize - uio->uio_loffset; 1379 1380 error = dmu_read_uio(zv->zv_objset, ZVOL_OBJ, uio, bytes); 1381 if (error) { 1382 /* convert checksum errors into IO errors */ 1383 if (error == ECKSUM) 1384 error = SET_ERROR(EIO); 1385 break; 1386 } 1387 } 1388 rangelock_exit(lr); 1389 1390 smt_end_unsafe(); 1391 1392 return (error); 1393 } 1394 1395 /*ARGSUSED*/ 1396 int 1397 zvol_write(dev_t dev, uio_t *uio, cred_t *cr) 1398 { 1399 minor_t minor = getminor(dev); 1400 zvol_state_t *zv; 1401 uint64_t volsize; 1402 int error = 0; 1403 boolean_t sync; 1404 1405 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1406 if (zv == NULL) 1407 return (SET_ERROR(ENXIO)); 1408 1409 volsize = zv->zv_volsize; 1410 if (uio->uio_resid > 0 && 1411 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize)) 1412 return (SET_ERROR(EIO)); 1413 1414 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1415 error = physio(zvol_strategy, NULL, dev, B_WRITE, 1416 zvol_minphys, uio); 1417 return (error); 1418 } 1419 1420 smt_begin_unsafe(); 1421 1422 sync = !(zv->zv_flags & ZVOL_WCE) || 1423 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS); 1424 1425 locked_range_t *lr = rangelock_enter(&zv->zv_rangelock, 1426 uio->uio_loffset, uio->uio_resid, RL_WRITER); 1427 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1428 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1429 uint64_t off = uio->uio_loffset; 1430 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset); 1431 1432 if (bytes > volsize - off) /* don't write past the end */ 1433 bytes = volsize - off; 1434 1435 dmu_tx_hold_write_by_dnode(tx, zv->zv_dn, off, bytes); 1436 error = dmu_tx_assign(tx, TXG_WAIT); 1437 if (error) { 1438 dmu_tx_abort(tx); 1439 break; 1440 } 1441 error = dmu_write_uio_dnode(zv->zv_dn, uio, bytes, tx); 1442 if (error == 0) 1443 zvol_log_write(zv, tx, off, bytes, sync); 1444 dmu_tx_commit(tx); 1445 1446 if (error) 1447 break; 1448 } 1449 rangelock_exit(lr); 1450 1451 if (sync) 1452 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1453 1454 smt_end_unsafe(); 1455 1456 return (error); 1457 } 1458 1459 int 1460 zvol_getefi(void *arg, int flag, uint64_t vs, uint8_t bs) 1461 { 1462 struct uuid uuid = EFI_RESERVED; 1463 efi_gpe_t gpe = { 0 }; 1464 uint32_t crc; 1465 dk_efi_t efi; 1466 int length; 1467 char *ptr; 1468 1469 if (ddi_copyin(arg, &efi, sizeof (dk_efi_t), flag)) 1470 return (SET_ERROR(EFAULT)); 1471 ptr = (char *)(uintptr_t)efi.dki_data_64; 1472 length = efi.dki_length; 1473 /* 1474 * Some clients may attempt to request a PMBR for the 1475 * zvol. Currently this interface will return EINVAL to 1476 * such requests. These requests could be supported by 1477 * adding a check for lba == 0 and consing up an appropriate 1478 * PMBR. 1479 */ 1480 if (efi.dki_lba < 1 || efi.dki_lba > 2 || length <= 0) 1481 return (SET_ERROR(EINVAL)); 1482 1483 gpe.efi_gpe_StartingLBA = LE_64(34ULL); 1484 gpe.efi_gpe_EndingLBA = LE_64((vs >> bs) - 1); 1485 UUID_LE_CONVERT(gpe.efi_gpe_PartitionTypeGUID, uuid); 1486 1487 if (efi.dki_lba == 1) { 1488 efi_gpt_t gpt = { 0 }; 1489 1490 gpt.efi_gpt_Signature = LE_64(EFI_SIGNATURE); 1491 gpt.efi_gpt_Revision = LE_32(EFI_VERSION_CURRENT); 1492 gpt.efi_gpt_HeaderSize = LE_32(EFI_HEADER_SIZE); 1493 gpt.efi_gpt_MyLBA = LE_64(1ULL); 1494 gpt.efi_gpt_FirstUsableLBA = LE_64(34ULL); 1495 gpt.efi_gpt_LastUsableLBA = LE_64((vs >> bs) - 1); 1496 gpt.efi_gpt_PartitionEntryLBA = LE_64(2ULL); 1497 gpt.efi_gpt_NumberOfPartitionEntries = LE_32(1); 1498 gpt.efi_gpt_SizeOfPartitionEntry = 1499 LE_32(sizeof (efi_gpe_t)); 1500 CRC32(crc, &gpe, sizeof (gpe), -1U, crc32_table); 1501 gpt.efi_gpt_PartitionEntryArrayCRC32 = LE_32(~crc); 1502 CRC32(crc, &gpt, EFI_HEADER_SIZE, -1U, crc32_table); 1503 gpt.efi_gpt_HeaderCRC32 = LE_32(~crc); 1504 if (ddi_copyout(&gpt, ptr, MIN(sizeof (gpt), length), 1505 flag)) 1506 return (SET_ERROR(EFAULT)); 1507 ptr += sizeof (gpt); 1508 length -= sizeof (gpt); 1509 } 1510 if (length > 0 && ddi_copyout(&gpe, ptr, MIN(sizeof (gpe), 1511 length), flag)) 1512 return (SET_ERROR(EFAULT)); 1513 return (0); 1514 } 1515 1516 /* 1517 * BEGIN entry points to allow external callers access to the volume. 1518 */ 1519 /* 1520 * Return the volume parameters needed for access from an external caller. 1521 * These values are invariant as long as the volume is held open. 1522 */ 1523 int 1524 zvol_get_volume_params(minor_t minor, uint64_t *blksize, 1525 uint64_t *max_xfer_len, void **minor_hdl, void **objset_hdl, void **zil_hdl, 1526 void **rl_hdl, void **dnode_hdl) 1527 { 1528 zvol_state_t *zv; 1529 1530 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1531 if (zv == NULL) 1532 return (SET_ERROR(ENXIO)); 1533 if (zv->zv_flags & ZVOL_DUMPIFIED) 1534 return (SET_ERROR(ENXIO)); 1535 1536 ASSERT(blksize && max_xfer_len && minor_hdl && 1537 objset_hdl && zil_hdl && rl_hdl && dnode_hdl); 1538 1539 *blksize = zv->zv_volblocksize; 1540 *max_xfer_len = (uint64_t)zvol_maxphys; 1541 *minor_hdl = zv; 1542 *objset_hdl = zv->zv_objset; 1543 *zil_hdl = zv->zv_zilog; 1544 *rl_hdl = &zv->zv_rangelock; 1545 *dnode_hdl = zv->zv_dn; 1546 return (0); 1547 } 1548 1549 /* 1550 * Return the current volume size to an external caller. 1551 * The size can change while the volume is open. 1552 */ 1553 uint64_t 1554 zvol_get_volume_size(void *minor_hdl) 1555 { 1556 zvol_state_t *zv = minor_hdl; 1557 1558 return (zv->zv_volsize); 1559 } 1560 1561 /* 1562 * Return the current WCE setting to an external caller. 1563 * The WCE setting can change while the volume is open. 1564 */ 1565 int 1566 zvol_get_volume_wce(void *minor_hdl) 1567 { 1568 zvol_state_t *zv = minor_hdl; 1569 1570 return ((zv->zv_flags & ZVOL_WCE) ? 1 : 0); 1571 } 1572 1573 /* 1574 * Entry point for external callers to zvol_log_write 1575 */ 1576 void 1577 zvol_log_write_minor(void *minor_hdl, dmu_tx_t *tx, offset_t off, ssize_t resid, 1578 boolean_t sync) 1579 { 1580 zvol_state_t *zv = minor_hdl; 1581 1582 zvol_log_write(zv, tx, off, resid, sync); 1583 } 1584 /* 1585 * END entry points to allow external callers access to the volume. 1586 */ 1587 1588 /* 1589 * Log a DKIOCFREE/free-long-range to the ZIL with TX_TRUNCATE. 1590 */ 1591 static void 1592 zvol_log_truncate(zvol_state_t *zv, dmu_tx_t *tx, uint64_t off, uint64_t len, 1593 boolean_t sync) 1594 { 1595 itx_t *itx; 1596 lr_truncate_t *lr; 1597 zilog_t *zilog = zv->zv_zilog; 1598 1599 if (zil_replaying(zilog, tx)) 1600 return; 1601 1602 itx = zil_itx_create(TX_TRUNCATE, sizeof (*lr)); 1603 lr = (lr_truncate_t *)&itx->itx_lr; 1604 lr->lr_foid = ZVOL_OBJ; 1605 lr->lr_offset = off; 1606 lr->lr_length = len; 1607 1608 itx->itx_sync = sync; 1609 zil_itx_assign(zilog, itx, tx); 1610 } 1611 1612 /* 1613 * Dirtbag ioctls to support mkfs(1M) for UFS filesystems. See dkio(7I). 1614 * Also a dirtbag dkio ioctl for unmap/free-block functionality. 1615 */ 1616 /*ARGSUSED*/ 1617 int 1618 zvol_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp) 1619 { 1620 zvol_state_t *zv; 1621 struct dk_callback *dkc; 1622 int i, error = 0; 1623 locked_range_t *lr; 1624 1625 mutex_enter(&zfsdev_state_lock); 1626 1627 zv = zfsdev_get_soft_state(getminor(dev), ZSST_ZVOL); 1628 1629 if (zv == NULL) { 1630 mutex_exit(&zfsdev_state_lock); 1631 return (SET_ERROR(ENXIO)); 1632 } 1633 ASSERT(zv->zv_total_opens > 0); 1634 1635 switch (cmd) { 1636 1637 case DKIOCINFO: 1638 { 1639 struct dk_cinfo dki; 1640 1641 bzero(&dki, sizeof (dki)); 1642 (void) strcpy(dki.dki_cname, "zvol"); 1643 (void) strcpy(dki.dki_dname, "zvol"); 1644 dki.dki_ctype = DKC_UNKNOWN; 1645 dki.dki_unit = getminor(dev); 1646 dki.dki_maxtransfer = 1647 1 << (SPA_OLD_MAXBLOCKSHIFT - zv->zv_min_bs); 1648 mutex_exit(&zfsdev_state_lock); 1649 if (ddi_copyout(&dki, (void *)arg, sizeof (dki), flag)) 1650 error = SET_ERROR(EFAULT); 1651 return (error); 1652 } 1653 1654 case DKIOCGMEDIAINFO: 1655 { 1656 struct dk_minfo dkm; 1657 1658 bzero(&dkm, sizeof (dkm)); 1659 dkm.dki_lbsize = 1U << zv->zv_min_bs; 1660 dkm.dki_capacity = zv->zv_volsize >> zv->zv_min_bs; 1661 dkm.dki_media_type = DK_UNKNOWN; 1662 mutex_exit(&zfsdev_state_lock); 1663 if (ddi_copyout(&dkm, (void *)arg, sizeof (dkm), flag)) 1664 error = SET_ERROR(EFAULT); 1665 return (error); 1666 } 1667 1668 case DKIOCGMEDIAINFOEXT: 1669 { 1670 struct dk_minfo_ext dkmext; 1671 1672 bzero(&dkmext, sizeof (dkmext)); 1673 dkmext.dki_lbsize = 1U << zv->zv_min_bs; 1674 dkmext.dki_pbsize = zv->zv_volblocksize; 1675 dkmext.dki_capacity = zv->zv_volsize >> zv->zv_min_bs; 1676 dkmext.dki_media_type = DK_UNKNOWN; 1677 mutex_exit(&zfsdev_state_lock); 1678 if (ddi_copyout(&dkmext, (void *)arg, sizeof (dkmext), flag)) 1679 error = SET_ERROR(EFAULT); 1680 return (error); 1681 } 1682 1683 case DKIOCGETEFI: 1684 { 1685 uint64_t vs = zv->zv_volsize; 1686 uint8_t bs = zv->zv_min_bs; 1687 1688 mutex_exit(&zfsdev_state_lock); 1689 error = zvol_getefi((void *)arg, flag, vs, bs); 1690 return (error); 1691 } 1692 1693 case DKIOCFLUSHWRITECACHE: 1694 dkc = (struct dk_callback *)arg; 1695 mutex_exit(&zfsdev_state_lock); 1696 1697 smt_begin_unsafe(); 1698 1699 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1700 if ((flag & FKIOCTL) && dkc != NULL && dkc->dkc_callback) { 1701 (*dkc->dkc_callback)(dkc->dkc_cookie, error); 1702 error = 0; 1703 } 1704 1705 smt_end_unsafe(); 1706 1707 return (error); 1708 1709 case DKIOCGETWCE: 1710 { 1711 int wce = (zv->zv_flags & ZVOL_WCE) ? 1 : 0; 1712 if (ddi_copyout(&wce, (void *)arg, sizeof (int), 1713 flag)) 1714 error = SET_ERROR(EFAULT); 1715 break; 1716 } 1717 case DKIOCSETWCE: 1718 { 1719 int wce; 1720 if (ddi_copyin((void *)arg, &wce, sizeof (int), 1721 flag)) { 1722 error = SET_ERROR(EFAULT); 1723 break; 1724 } 1725 if (wce) { 1726 zv->zv_flags |= ZVOL_WCE; 1727 mutex_exit(&zfsdev_state_lock); 1728 } else { 1729 zv->zv_flags &= ~ZVOL_WCE; 1730 mutex_exit(&zfsdev_state_lock); 1731 smt_begin_unsafe(); 1732 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1733 smt_end_unsafe(); 1734 } 1735 return (0); 1736 } 1737 1738 case DKIOCGGEOM: 1739 case DKIOCGVTOC: 1740 /* 1741 * commands using these (like prtvtoc) expect ENOTSUP 1742 * since we're emulating an EFI label 1743 */ 1744 error = SET_ERROR(ENOTSUP); 1745 break; 1746 1747 case DKIOCDUMPINIT: 1748 lr = rangelock_enter(&zv->zv_rangelock, 0, zv->zv_volsize, 1749 RL_WRITER); 1750 error = zvol_dumpify(zv); 1751 rangelock_exit(lr); 1752 break; 1753 1754 case DKIOCDUMPFINI: 1755 if (!(zv->zv_flags & ZVOL_DUMPIFIED)) 1756 break; 1757 lr = rangelock_enter(&zv->zv_rangelock, 0, zv->zv_volsize, 1758 RL_WRITER); 1759 error = zvol_dump_fini(zv); 1760 rangelock_exit(lr); 1761 break; 1762 1763 case DKIOCFREE: 1764 { 1765 dkioc_free_list_t *dfl; 1766 dmu_tx_t *tx; 1767 1768 if (!zvol_unmap_enabled) 1769 break; 1770 1771 if (!(flag & FKIOCTL)) { 1772 error = dfl_copyin((void *)arg, &dfl, flag, KM_SLEEP); 1773 if (error != 0) 1774 break; 1775 } else { 1776 dfl = (dkioc_free_list_t *)arg; 1777 ASSERT3U(dfl->dfl_num_exts, <=, DFL_COPYIN_MAX_EXTS); 1778 if (dfl->dfl_num_exts > DFL_COPYIN_MAX_EXTS) { 1779 error = SET_ERROR(EINVAL); 1780 break; 1781 } 1782 } 1783 1784 mutex_exit(&zfsdev_state_lock); 1785 1786 smt_begin_unsafe(); 1787 1788 for (int i = 0; i < dfl->dfl_num_exts; i++) { 1789 uint64_t start = dfl->dfl_exts[i].dfle_start, 1790 length = dfl->dfl_exts[i].dfle_length, 1791 end = start + length; 1792 1793 /* 1794 * Apply Postel's Law to length-checking. If they 1795 * overshoot, just blank out until the end, if there's 1796 * a need to blank out anything. 1797 */ 1798 if (start >= zv->zv_volsize) 1799 continue; /* No need to do anything... */ 1800 if (end > zv->zv_volsize) { 1801 end = DMU_OBJECT_END; 1802 length = end - start; 1803 } 1804 1805 lr = rangelock_enter(&zv->zv_rangelock, start, length, 1806 RL_WRITER); 1807 tx = dmu_tx_create(zv->zv_objset); 1808 error = dmu_tx_assign(tx, TXG_WAIT); 1809 if (error != 0) { 1810 dmu_tx_abort(tx); 1811 } else { 1812 zvol_log_truncate(zv, tx, start, length, 1813 B_TRUE); 1814 dmu_tx_commit(tx); 1815 error = dmu_free_long_range(zv->zv_objset, 1816 ZVOL_OBJ, start, length); 1817 } 1818 1819 rangelock_exit(lr); 1820 1821 if (error != 0) 1822 break; 1823 } 1824 1825 /* 1826 * If the write-cache is disabled, 'sync' property 1827 * is set to 'always', or if the caller is asking for 1828 * a synchronous free, commit this operation to the zil. 1829 * This will sync any previous uncommitted writes to the 1830 * zvol object. 1831 * Can be overridden by the zvol_unmap_sync_enabled tunable. 1832 */ 1833 if ((error == 0) && zvol_unmap_sync_enabled && 1834 (!(zv->zv_flags & ZVOL_WCE) || 1835 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS) || 1836 (dfl->dfl_flags & DF_WAIT_SYNC))) { 1837 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1838 } 1839 1840 if (!(flag & FKIOCTL)) 1841 dfl_free(dfl); 1842 1843 smt_end_unsafe(); 1844 1845 return (error); 1846 } 1847 1848 case DKIOC_CANFREE: 1849 i = zvol_unmap_enabled ? 1 : 0; 1850 if (ddi_copyout(&i, (void *)arg, sizeof (int), flag) != 0) { 1851 error = EFAULT; 1852 } else { 1853 error = 0; 1854 } 1855 break; 1856 1857 default: 1858 error = SET_ERROR(ENOTTY); 1859 break; 1860 1861 } 1862 mutex_exit(&zfsdev_state_lock); 1863 return (error); 1864 } 1865 1866 int 1867 zvol_busy(void) 1868 { 1869 return (zvol_minors != 0); 1870 } 1871 1872 void 1873 zvol_init(void) 1874 { 1875 VERIFY(ddi_soft_state_init(&zfsdev_state, sizeof (zfs_soft_state_t), 1876 1) == 0); 1877 mutex_init(&zfsdev_state_lock, NULL, MUTEX_DEFAULT, NULL); 1878 } 1879 1880 void 1881 zvol_fini(void) 1882 { 1883 mutex_destroy(&zfsdev_state_lock); 1884 ddi_soft_state_fini(&zfsdev_state); 1885 } 1886 1887 /*ARGSUSED*/ 1888 static int 1889 zfs_mvdev_dump_feature_check(void *arg, dmu_tx_t *tx) 1890 { 1891 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 1892 1893 if (spa_feature_is_active(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP)) 1894 return (1); 1895 return (0); 1896 } 1897 1898 /*ARGSUSED*/ 1899 static void 1900 zfs_mvdev_dump_activate_feature_sync(void *arg, dmu_tx_t *tx) 1901 { 1902 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 1903 1904 spa_feature_incr(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP, tx); 1905 } 1906 1907 static int 1908 zvol_dump_init(zvol_state_t *zv, boolean_t resize) 1909 { 1910 dmu_tx_t *tx; 1911 int error; 1912 objset_t *os = zv->zv_objset; 1913 spa_t *spa = dmu_objset_spa(os); 1914 vdev_t *vd = spa->spa_root_vdev; 1915 nvlist_t *nv = NULL; 1916 uint64_t version = spa_version(spa); 1917 uint64_t checksum, compress, refresrv, vbs, dedup; 1918 1919 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 1920 ASSERT(vd->vdev_ops == &vdev_root_ops); 1921 1922 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 0, 1923 DMU_OBJECT_END); 1924 if (error != 0) 1925 return (error); 1926 /* wait for dmu_free_long_range to actually free the blocks */ 1927 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 1928 1929 /* 1930 * If the pool on which the dump device is being initialized has more 1931 * than one child vdev, check that the MULTI_VDEV_CRASH_DUMP feature is 1932 * enabled. If so, bump that feature's counter to indicate that the 1933 * feature is active. We also check the vdev type to handle the 1934 * following case: 1935 * # zpool create test raidz disk1 disk2 disk3 1936 * Now have spa_root_vdev->vdev_children == 1 (the raidz vdev), 1937 * the raidz vdev itself has 3 children. 1938 */ 1939 if (vd->vdev_children > 1 || vd->vdev_ops == &vdev_raidz_ops) { 1940 if (!spa_feature_is_enabled(spa, 1941 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP)) 1942 return (SET_ERROR(ENOTSUP)); 1943 (void) dsl_sync_task(spa_name(spa), 1944 zfs_mvdev_dump_feature_check, 1945 zfs_mvdev_dump_activate_feature_sync, NULL, 1946 2, ZFS_SPACE_CHECK_RESERVED); 1947 } 1948 1949 if (!resize) { 1950 error = dsl_prop_get_integer(zv->zv_name, 1951 zfs_prop_to_name(ZFS_PROP_COMPRESSION), &compress, NULL); 1952 if (error == 0) { 1953 error = dsl_prop_get_integer(zv->zv_name, 1954 zfs_prop_to_name(ZFS_PROP_CHECKSUM), &checksum, 1955 NULL); 1956 } 1957 if (error == 0) { 1958 error = dsl_prop_get_integer(zv->zv_name, 1959 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 1960 &refresrv, NULL); 1961 } 1962 if (error == 0) { 1963 error = dsl_prop_get_integer(zv->zv_name, 1964 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &vbs, 1965 NULL); 1966 } 1967 if (version >= SPA_VERSION_DEDUP && error == 0) { 1968 error = dsl_prop_get_integer(zv->zv_name, 1969 zfs_prop_to_name(ZFS_PROP_DEDUP), &dedup, NULL); 1970 } 1971 } 1972 if (error != 0) 1973 return (error); 1974 1975 tx = dmu_tx_create(os); 1976 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 1977 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 1978 error = dmu_tx_assign(tx, TXG_WAIT); 1979 if (error != 0) { 1980 dmu_tx_abort(tx); 1981 return (error); 1982 } 1983 1984 /* 1985 * If we are resizing the dump device then we only need to 1986 * update the refreservation to match the newly updated 1987 * zvolsize. Otherwise, we save off the original state of the 1988 * zvol so that we can restore them if the zvol is ever undumpified. 1989 */ 1990 if (resize) { 1991 error = zap_update(os, ZVOL_ZAP_OBJ, 1992 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 1993 &zv->zv_volsize, tx); 1994 } else { 1995 error = zap_update(os, ZVOL_ZAP_OBJ, 1996 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, 1997 &compress, tx); 1998 if (error == 0) { 1999 error = zap_update(os, ZVOL_ZAP_OBJ, 2000 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, 2001 &checksum, tx); 2002 } 2003 if (error == 0) { 2004 error = zap_update(os, ZVOL_ZAP_OBJ, 2005 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 2006 &refresrv, tx); 2007 } 2008 if (error == 0) { 2009 error = zap_update(os, ZVOL_ZAP_OBJ, 2010 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, 2011 &vbs, tx); 2012 } 2013 if (error == 0) { 2014 error = dmu_object_set_blocksize( 2015 os, ZVOL_OBJ, SPA_OLD_MAXBLOCKSIZE, 0, tx); 2016 } 2017 if (version >= SPA_VERSION_DEDUP && error == 0) { 2018 error = zap_update(os, ZVOL_ZAP_OBJ, 2019 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, 2020 &dedup, tx); 2021 } 2022 if (error == 0) 2023 zv->zv_volblocksize = SPA_OLD_MAXBLOCKSIZE; 2024 } 2025 dmu_tx_commit(tx); 2026 2027 /* 2028 * We only need update the zvol's property if we are initializing 2029 * the dump area for the first time. 2030 */ 2031 if (error == 0 && !resize) { 2032 /* 2033 * If MULTI_VDEV_CRASH_DUMP is active, use the NOPARITY checksum 2034 * function. Otherwise, use the old default -- OFF. 2035 */ 2036 checksum = spa_feature_is_active(spa, 2037 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP) ? ZIO_CHECKSUM_NOPARITY : 2038 ZIO_CHECKSUM_OFF; 2039 2040 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 2041 VERIFY(nvlist_add_uint64(nv, 2042 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 0) == 0); 2043 VERIFY(nvlist_add_uint64(nv, 2044 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 2045 ZIO_COMPRESS_OFF) == 0); 2046 VERIFY(nvlist_add_uint64(nv, 2047 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 2048 checksum) == 0); 2049 if (version >= SPA_VERSION_DEDUP) { 2050 VERIFY(nvlist_add_uint64(nv, 2051 zfs_prop_to_name(ZFS_PROP_DEDUP), 2052 ZIO_CHECKSUM_OFF) == 0); 2053 } 2054 2055 error = zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL, 2056 nv, NULL); 2057 nvlist_free(nv); 2058 } 2059 2060 /* Allocate the space for the dump */ 2061 if (error == 0) 2062 error = zvol_prealloc(zv); 2063 return (error); 2064 } 2065 2066 static int 2067 zvol_dumpify(zvol_state_t *zv) 2068 { 2069 int error = 0; 2070 uint64_t dumpsize = 0; 2071 dmu_tx_t *tx; 2072 objset_t *os = zv->zv_objset; 2073 2074 if (zv->zv_flags & ZVOL_RDONLY) 2075 return (SET_ERROR(EROFS)); 2076 2077 if (os->os_encrypted) 2078 return (SET_ERROR(ENOTSUP)); 2079 2080 if (zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 2081 8, 1, &dumpsize) != 0 || dumpsize != zv->zv_volsize) { 2082 boolean_t resize = (dumpsize > 0); 2083 2084 if ((error = zvol_dump_init(zv, resize)) != 0) { 2085 (void) zvol_dump_fini(zv); 2086 return (error); 2087 } 2088 } 2089 2090 /* 2091 * Build up our lba mapping. 2092 */ 2093 error = zvol_get_lbas(zv); 2094 if (error) { 2095 (void) zvol_dump_fini(zv); 2096 return (error); 2097 } 2098 2099 tx = dmu_tx_create(os); 2100 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 2101 error = dmu_tx_assign(tx, TXG_WAIT); 2102 if (error) { 2103 dmu_tx_abort(tx); 2104 (void) zvol_dump_fini(zv); 2105 return (error); 2106 } 2107 2108 zv->zv_flags |= ZVOL_DUMPIFIED; 2109 error = zap_update(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 8, 1, 2110 &zv->zv_volsize, tx); 2111 dmu_tx_commit(tx); 2112 2113 if (error) { 2114 (void) zvol_dump_fini(zv); 2115 return (error); 2116 } 2117 2118 txg_wait_synced(dmu_objset_pool(os), 0); 2119 return (0); 2120 } 2121 2122 static int 2123 zvol_dump_fini(zvol_state_t *zv) 2124 { 2125 dmu_tx_t *tx; 2126 objset_t *os = zv->zv_objset; 2127 nvlist_t *nv; 2128 int error = 0; 2129 uint64_t checksum, compress, refresrv, vbs, dedup; 2130 uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset)); 2131 2132 /* 2133 * Attempt to restore the zvol back to its pre-dumpified state. 2134 * This is a best-effort attempt as it's possible that not all 2135 * of these properties were initialized during the dumpify process 2136 * (i.e. error during zvol_dump_init). 2137 */ 2138 2139 tx = dmu_tx_create(os); 2140 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 2141 error = dmu_tx_assign(tx, TXG_WAIT); 2142 if (error) { 2143 dmu_tx_abort(tx); 2144 return (error); 2145 } 2146 (void) zap_remove(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, tx); 2147 dmu_tx_commit(tx); 2148 2149 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2150 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum); 2151 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2152 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, &compress); 2153 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2154 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, &refresrv); 2155 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2156 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, &vbs); 2157 2158 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 2159 (void) nvlist_add_uint64(nv, 2160 zfs_prop_to_name(ZFS_PROP_CHECKSUM), checksum); 2161 (void) nvlist_add_uint64(nv, 2162 zfs_prop_to_name(ZFS_PROP_COMPRESSION), compress); 2163 (void) nvlist_add_uint64(nv, 2164 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), refresrv); 2165 if (version >= SPA_VERSION_DEDUP && 2166 zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2167 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, &dedup) == 0) { 2168 (void) nvlist_add_uint64(nv, 2169 zfs_prop_to_name(ZFS_PROP_DEDUP), dedup); 2170 } 2171 (void) zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL, 2172 nv, NULL); 2173 nvlist_free(nv); 2174 2175 zvol_free_extents(zv); 2176 zv->zv_flags &= ~ZVOL_DUMPIFIED; 2177 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, DMU_OBJECT_END); 2178 /* wait for dmu_free_long_range to actually free the blocks */ 2179 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 2180 tx = dmu_tx_create(os); 2181 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 2182 error = dmu_tx_assign(tx, TXG_WAIT); 2183 if (error) { 2184 dmu_tx_abort(tx); 2185 return (error); 2186 } 2187 if (dmu_object_set_blocksize(os, ZVOL_OBJ, vbs, 0, tx) == 0) 2188 zv->zv_volblocksize = vbs; 2189 dmu_tx_commit(tx); 2190 2191 return (0); 2192 } 2193