1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * 24 * Portions Copyright 2010 Robert Milkowski 25 * 26 * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 27 * Copyright (c) 2012, 2014 by Delphix. All rights reserved. 28 * Copyright (c) 2013, Joyent, Inc. All rights reserved. 29 */ 30 31 /* 32 * ZFS volume emulation driver. 33 * 34 * Makes a DMU object look like a volume of arbitrary size, up to 2^64 bytes. 35 * Volumes are accessed through the symbolic links named: 36 * 37 * /dev/zvol/dsk/<pool_name>/<dataset_name> 38 * /dev/zvol/rdsk/<pool_name>/<dataset_name> 39 * 40 * These links are created by the /dev filesystem (sdev_zvolops.c). 41 * Volumes are persistent through reboot. No user command needs to be 42 * run before opening and using a device. 43 */ 44 45 #include <sys/types.h> 46 #include <sys/param.h> 47 #include <sys/errno.h> 48 #include <sys/uio.h> 49 #include <sys/buf.h> 50 #include <sys/modctl.h> 51 #include <sys/open.h> 52 #include <sys/kmem.h> 53 #include <sys/conf.h> 54 #include <sys/cmn_err.h> 55 #include <sys/stat.h> 56 #include <sys/zap.h> 57 #include <sys/spa.h> 58 #include <sys/spa_impl.h> 59 #include <sys/zio.h> 60 #include <sys/dmu_traverse.h> 61 #include <sys/dnode.h> 62 #include <sys/dsl_dataset.h> 63 #include <sys/dsl_prop.h> 64 #include <sys/dkio.h> 65 #include <sys/efi_partition.h> 66 #include <sys/byteorder.h> 67 #include <sys/pathname.h> 68 #include <sys/ddi.h> 69 #include <sys/sunddi.h> 70 #include <sys/crc32.h> 71 #include <sys/dirent.h> 72 #include <sys/policy.h> 73 #include <sys/fs/zfs.h> 74 #include <sys/zfs_ioctl.h> 75 #include <sys/mkdev.h> 76 #include <sys/zil.h> 77 #include <sys/refcount.h> 78 #include <sys/zfs_znode.h> 79 #include <sys/zfs_rlock.h> 80 #include <sys/vdev_disk.h> 81 #include <sys/vdev_impl.h> 82 #include <sys/vdev_raidz.h> 83 #include <sys/zvol.h> 84 #include <sys/dumphdr.h> 85 #include <sys/zil_impl.h> 86 #include <sys/dbuf.h> 87 #include <sys/zfs_events.h> 88 #include <sys/dmu_tx.h> 89 #include <sys/zfeature.h> 90 #include <sys/zio_checksum.h> 91 92 #include "zfs_namecheck.h" 93 94 void *zfsdev_state; 95 static char *zvol_tag = "zvol_tag"; 96 97 #define ZVOL_DUMPSIZE "dumpsize" 98 99 /* 100 * This lock protects the zfsdev_state structure from being modified 101 * while it's being used, e.g. an open that comes in before a create 102 * finishes. It also protects temporary opens of the dataset so that, 103 * e.g., an open doesn't get a spurious EBUSY. 104 */ 105 kmutex_t zfsdev_state_lock; 106 static uint32_t zvol_minors; 107 108 typedef struct zvol_extent { 109 list_node_t ze_node; 110 dva_t ze_dva; /* dva associated with this extent */ 111 uint64_t ze_nblks; /* number of blocks in extent */ 112 } zvol_extent_t; 113 114 /* 115 * The in-core state of each volume. 116 */ 117 typedef struct zvol_state { 118 char zv_name[MAXPATHLEN]; /* pool/dd name */ 119 uint64_t zv_volsize; /* amount of space we advertise */ 120 uint64_t zv_volblocksize; /* volume block size */ 121 minor_t zv_minor; /* minor number */ 122 uint8_t zv_min_bs; /* minimum addressable block shift */ 123 uint8_t zv_flags; /* readonly, dumpified, etc. */ 124 objset_t *zv_objset; /* objset handle */ 125 uint32_t zv_open_count[OTYPCNT]; /* open counts */ 126 uint32_t zv_total_opens; /* total open count */ 127 zilog_t *zv_zilog; /* ZIL handle */ 128 list_t zv_extents; /* List of extents for dump */ 129 znode_t zv_znode; /* for range locking */ 130 dmu_buf_t *zv_dbuf; /* bonus handle */ 131 } zvol_state_t; 132 133 /* 134 * zvol specific flags 135 */ 136 #define ZVOL_RDONLY 0x1 137 #define ZVOL_DUMPIFIED 0x2 138 #define ZVOL_EXCL 0x4 139 #define ZVOL_WCE 0x8 140 141 /* 142 * zvol maximum transfer in one DMU tx. 143 */ 144 int zvol_maxphys = DMU_MAX_ACCESS/2; 145 146 /* 147 * Toggle unmap functionality. 148 */ 149 boolean_t zvol_unmap_enabled = B_TRUE; 150 151 extern int zfs_set_prop_nvlist(const char *, zprop_source_t, 152 nvlist_t *, nvlist_t *); 153 static int zvol_remove_zv(zvol_state_t *); 154 static int zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio); 155 static int zvol_dumpify(zvol_state_t *zv); 156 static int zvol_dump_fini(zvol_state_t *zv); 157 static int zvol_dump_init(zvol_state_t *zv, boolean_t resize); 158 159 static void 160 zvol_size_changed(zvol_state_t *zv, uint64_t volsize) 161 { 162 dev_t dev = makedevice(ddi_driver_major(zfs_dip), zv->zv_minor); 163 164 zv->zv_volsize = volsize; 165 VERIFY(ddi_prop_update_int64(dev, zfs_dip, 166 "Size", volsize) == DDI_SUCCESS); 167 VERIFY(ddi_prop_update_int64(dev, zfs_dip, 168 "Nblocks", lbtodb(volsize)) == DDI_SUCCESS); 169 170 /* Notify specfs to invalidate the cached size */ 171 spec_size_invalidate(dev, VBLK); 172 spec_size_invalidate(dev, VCHR); 173 } 174 175 int 176 zvol_check_volsize(uint64_t volsize, uint64_t blocksize) 177 { 178 if (volsize == 0) 179 return (SET_ERROR(EINVAL)); 180 181 if (volsize % blocksize != 0) 182 return (SET_ERROR(EINVAL)); 183 184 #ifdef _ILP32 185 if (volsize - 1 > SPEC_MAXOFFSET_T) 186 return (SET_ERROR(EOVERFLOW)); 187 #endif 188 return (0); 189 } 190 191 int 192 zvol_check_volblocksize(uint64_t volblocksize) 193 { 194 if (volblocksize < SPA_MINBLOCKSIZE || 195 volblocksize > SPA_OLD_MAXBLOCKSIZE || 196 !ISP2(volblocksize)) 197 return (SET_ERROR(EDOM)); 198 199 return (0); 200 } 201 202 int 203 zvol_get_stats(objset_t *os, nvlist_t *nv) 204 { 205 int error; 206 dmu_object_info_t doi; 207 uint64_t val; 208 209 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val); 210 if (error) 211 return (error); 212 213 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val); 214 215 error = dmu_object_info(os, ZVOL_OBJ, &doi); 216 217 if (error == 0) { 218 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE, 219 doi.doi_data_block_size); 220 } 221 222 return (error); 223 } 224 225 static zvol_state_t * 226 zvol_minor_lookup(const char *name) 227 { 228 minor_t minor; 229 zvol_state_t *zv; 230 231 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 232 233 for (minor = 1; minor <= ZFSDEV_MAX_MINOR; minor++) { 234 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 235 if (zv == NULL) 236 continue; 237 if (strcmp(zv->zv_name, name) == 0) 238 return (zv); 239 } 240 241 return (NULL); 242 } 243 244 /* extent mapping arg */ 245 struct maparg { 246 zvol_state_t *ma_zv; 247 uint64_t ma_blks; 248 }; 249 250 /*ARGSUSED*/ 251 static int 252 zvol_map_block(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, 253 const zbookmark_phys_t *zb, const dnode_phys_t *dnp, void *arg) 254 { 255 struct maparg *ma = arg; 256 zvol_extent_t *ze; 257 int bs = ma->ma_zv->zv_volblocksize; 258 259 if (BP_IS_HOLE(bp) || 260 zb->zb_object != ZVOL_OBJ || zb->zb_level != 0) 261 return (0); 262 263 VERIFY(!BP_IS_EMBEDDED(bp)); 264 265 VERIFY3U(ma->ma_blks, ==, zb->zb_blkid); 266 ma->ma_blks++; 267 268 /* Abort immediately if we have encountered gang blocks */ 269 if (BP_IS_GANG(bp)) 270 return (SET_ERROR(EFRAGS)); 271 272 /* 273 * See if the block is at the end of the previous extent. 274 */ 275 ze = list_tail(&ma->ma_zv->zv_extents); 276 if (ze && 277 DVA_GET_VDEV(BP_IDENTITY(bp)) == DVA_GET_VDEV(&ze->ze_dva) && 278 DVA_GET_OFFSET(BP_IDENTITY(bp)) == 279 DVA_GET_OFFSET(&ze->ze_dva) + ze->ze_nblks * bs) { 280 ze->ze_nblks++; 281 return (0); 282 } 283 284 dprintf_bp(bp, "%s", "next blkptr:"); 285 286 /* start a new extent */ 287 ze = kmem_zalloc(sizeof (zvol_extent_t), KM_SLEEP); 288 ze->ze_dva = bp->blk_dva[0]; /* structure assignment */ 289 ze->ze_nblks = 1; 290 list_insert_tail(&ma->ma_zv->zv_extents, ze); 291 return (0); 292 } 293 294 static void 295 zvol_free_extents(zvol_state_t *zv) 296 { 297 zvol_extent_t *ze; 298 299 while (ze = list_head(&zv->zv_extents)) { 300 list_remove(&zv->zv_extents, ze); 301 kmem_free(ze, sizeof (zvol_extent_t)); 302 } 303 } 304 305 static int 306 zvol_get_lbas(zvol_state_t *zv) 307 { 308 objset_t *os = zv->zv_objset; 309 struct maparg ma; 310 int err; 311 312 ma.ma_zv = zv; 313 ma.ma_blks = 0; 314 zvol_free_extents(zv); 315 316 /* commit any in-flight changes before traversing the dataset */ 317 txg_wait_synced(dmu_objset_pool(os), 0); 318 err = traverse_dataset(dmu_objset_ds(os), 0, 319 TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA, zvol_map_block, &ma); 320 if (err || ma.ma_blks != (zv->zv_volsize / zv->zv_volblocksize)) { 321 zvol_free_extents(zv); 322 return (err ? err : EIO); 323 } 324 325 return (0); 326 } 327 328 /* ARGSUSED */ 329 void 330 zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx) 331 { 332 zfs_creat_t *zct = arg; 333 nvlist_t *nvprops = zct->zct_props; 334 int error; 335 uint64_t volblocksize, volsize; 336 337 VERIFY(nvlist_lookup_uint64(nvprops, 338 zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0); 339 if (nvlist_lookup_uint64(nvprops, 340 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0) 341 volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE); 342 343 /* 344 * These properties must be removed from the list so the generic 345 * property setting step won't apply to them. 346 */ 347 VERIFY(nvlist_remove_all(nvprops, 348 zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0); 349 (void) nvlist_remove_all(nvprops, 350 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE)); 351 352 error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize, 353 DMU_OT_NONE, 0, tx); 354 ASSERT(error == 0); 355 356 error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP, 357 DMU_OT_NONE, 0, tx); 358 ASSERT(error == 0); 359 360 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx); 361 ASSERT(error == 0); 362 } 363 364 /* 365 * Replay a TX_TRUNCATE ZIL transaction if asked. TX_TRUNCATE is how we 366 * implement DKIOCFREE/free-long-range. 367 */ 368 static int 369 zvol_replay_truncate(zvol_state_t *zv, lr_truncate_t *lr, boolean_t byteswap) 370 { 371 uint64_t offset, length; 372 373 if (byteswap) 374 byteswap_uint64_array(lr, sizeof (*lr)); 375 376 offset = lr->lr_offset; 377 length = lr->lr_length; 378 379 return (dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, offset, length)); 380 } 381 382 /* 383 * Replay a TX_WRITE ZIL transaction that didn't get committed 384 * after a system failure 385 */ 386 static int 387 zvol_replay_write(zvol_state_t *zv, lr_write_t *lr, boolean_t byteswap) 388 { 389 objset_t *os = zv->zv_objset; 390 char *data = (char *)(lr + 1); /* data follows lr_write_t */ 391 uint64_t offset, length; 392 dmu_tx_t *tx; 393 int error; 394 395 if (byteswap) 396 byteswap_uint64_array(lr, sizeof (*lr)); 397 398 offset = lr->lr_offset; 399 length = lr->lr_length; 400 401 /* If it's a dmu_sync() block, write the whole block */ 402 if (lr->lr_common.lrc_reclen == sizeof (lr_write_t)) { 403 uint64_t blocksize = BP_GET_LSIZE(&lr->lr_blkptr); 404 if (length < blocksize) { 405 offset -= offset % blocksize; 406 length = blocksize; 407 } 408 } 409 410 tx = dmu_tx_create(os); 411 dmu_tx_hold_write(tx, ZVOL_OBJ, offset, length); 412 error = dmu_tx_assign(tx, TXG_WAIT); 413 if (error) { 414 dmu_tx_abort(tx); 415 } else { 416 dmu_write(os, ZVOL_OBJ, offset, length, data, tx); 417 dmu_tx_commit(tx); 418 } 419 420 return (error); 421 } 422 423 /* ARGSUSED */ 424 static int 425 zvol_replay_err(zvol_state_t *zv, lr_t *lr, boolean_t byteswap) 426 { 427 return (SET_ERROR(ENOTSUP)); 428 } 429 430 /* 431 * Callback vectors for replaying records. 432 * Only TX_WRITE and TX_TRUNCATE are needed for zvol. 433 */ 434 zil_replay_func_t *zvol_replay_vector[TX_MAX_TYPE] = { 435 zvol_replay_err, /* 0 no such transaction type */ 436 zvol_replay_err, /* TX_CREATE */ 437 zvol_replay_err, /* TX_MKDIR */ 438 zvol_replay_err, /* TX_MKXATTR */ 439 zvol_replay_err, /* TX_SYMLINK */ 440 zvol_replay_err, /* TX_REMOVE */ 441 zvol_replay_err, /* TX_RMDIR */ 442 zvol_replay_err, /* TX_LINK */ 443 zvol_replay_err, /* TX_RENAME */ 444 zvol_replay_write, /* TX_WRITE */ 445 zvol_replay_truncate, /* TX_TRUNCATE */ 446 zvol_replay_err, /* TX_SETATTR */ 447 zvol_replay_err, /* TX_ACL */ 448 zvol_replay_err, /* TX_CREATE_ACL */ 449 zvol_replay_err, /* TX_CREATE_ATTR */ 450 zvol_replay_err, /* TX_CREATE_ACL_ATTR */ 451 zvol_replay_err, /* TX_MKDIR_ACL */ 452 zvol_replay_err, /* TX_MKDIR_ATTR */ 453 zvol_replay_err, /* TX_MKDIR_ACL_ATTR */ 454 zvol_replay_err, /* TX_WRITE2 */ 455 }; 456 457 int 458 zvol_name2minor(const char *name, minor_t *minor) 459 { 460 zvol_state_t *zv; 461 462 mutex_enter(&zfsdev_state_lock); 463 zv = zvol_minor_lookup(name); 464 if (minor && zv) 465 *minor = zv->zv_minor; 466 mutex_exit(&zfsdev_state_lock); 467 return (zv ? 0 : -1); 468 } 469 470 /* 471 * Create a minor node (plus a whole lot more) for the specified volume. 472 */ 473 int 474 zvol_create_minor(const char *name) 475 { 476 zfs_soft_state_t *zs; 477 zvol_state_t *zv; 478 objset_t *os; 479 dmu_object_info_t doi; 480 minor_t minor = 0; 481 char chrbuf[30], blkbuf[30]; 482 int error; 483 484 mutex_enter(&zfsdev_state_lock); 485 486 if (zvol_minor_lookup(name) != NULL) { 487 mutex_exit(&zfsdev_state_lock); 488 return (SET_ERROR(EEXIST)); 489 } 490 491 /* lie and say we're read-only */ 492 error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, FTAG, &os); 493 494 if (error) { 495 mutex_exit(&zfsdev_state_lock); 496 return (error); 497 } 498 499 if ((minor = zfsdev_minor_alloc()) == 0) { 500 dmu_objset_disown(os, FTAG); 501 mutex_exit(&zfsdev_state_lock); 502 return (SET_ERROR(ENXIO)); 503 } 504 505 if (ddi_soft_state_zalloc(zfsdev_state, minor) != DDI_SUCCESS) { 506 dmu_objset_disown(os, FTAG); 507 mutex_exit(&zfsdev_state_lock); 508 return (SET_ERROR(EAGAIN)); 509 } 510 (void) ddi_prop_update_string(minor, zfs_dip, ZVOL_PROP_NAME, 511 (char *)name); 512 513 (void) snprintf(chrbuf, sizeof (chrbuf), "%u,raw", minor); 514 515 if (ddi_create_minor_node(zfs_dip, chrbuf, S_IFCHR, 516 minor, DDI_PSEUDO, 0) == DDI_FAILURE) { 517 ddi_soft_state_free(zfsdev_state, minor); 518 dmu_objset_disown(os, FTAG); 519 mutex_exit(&zfsdev_state_lock); 520 return (SET_ERROR(EAGAIN)); 521 } 522 523 (void) snprintf(blkbuf, sizeof (blkbuf), "%u", minor); 524 525 if (ddi_create_minor_node(zfs_dip, blkbuf, S_IFBLK, 526 minor, DDI_PSEUDO, 0) == DDI_FAILURE) { 527 ddi_remove_minor_node(zfs_dip, chrbuf); 528 ddi_soft_state_free(zfsdev_state, minor); 529 dmu_objset_disown(os, FTAG); 530 mutex_exit(&zfsdev_state_lock); 531 return (SET_ERROR(EAGAIN)); 532 } 533 534 zs = ddi_get_soft_state(zfsdev_state, minor); 535 zs->zss_type = ZSST_ZVOL; 536 zv = zs->zss_data = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP); 537 (void) strlcpy(zv->zv_name, name, MAXPATHLEN); 538 zv->zv_min_bs = DEV_BSHIFT; 539 zv->zv_minor = minor; 540 zv->zv_objset = os; 541 if (dmu_objset_is_snapshot(os) || !spa_writeable(dmu_objset_spa(os))) 542 zv->zv_flags |= ZVOL_RDONLY; 543 mutex_init(&zv->zv_znode.z_range_lock, NULL, MUTEX_DEFAULT, NULL); 544 avl_create(&zv->zv_znode.z_range_avl, zfs_range_compare, 545 sizeof (rl_t), offsetof(rl_t, r_node)); 546 list_create(&zv->zv_extents, sizeof (zvol_extent_t), 547 offsetof(zvol_extent_t, ze_node)); 548 /* get and cache the blocksize */ 549 error = dmu_object_info(os, ZVOL_OBJ, &doi); 550 ASSERT(error == 0); 551 zv->zv_volblocksize = doi.doi_data_block_size; 552 553 if (spa_writeable(dmu_objset_spa(os))) { 554 if (zil_replay_disable) 555 zil_destroy(dmu_objset_zil(os), B_FALSE); 556 else 557 zil_replay(os, zv, zvol_replay_vector); 558 } 559 dmu_objset_disown(os, FTAG); 560 zv->zv_objset = NULL; 561 562 zvol_minors++; 563 564 mutex_exit(&zfsdev_state_lock); 565 566 return (0); 567 } 568 569 /* 570 * Remove minor node for the specified volume. 571 */ 572 static int 573 zvol_remove_zv(zvol_state_t *zv) 574 { 575 char nmbuf[20]; 576 minor_t minor = zv->zv_minor; 577 578 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 579 if (zv->zv_total_opens != 0) 580 return (SET_ERROR(EBUSY)); 581 582 (void) snprintf(nmbuf, sizeof (nmbuf), "%u,raw", minor); 583 ddi_remove_minor_node(zfs_dip, nmbuf); 584 585 (void) snprintf(nmbuf, sizeof (nmbuf), "%u", minor); 586 ddi_remove_minor_node(zfs_dip, nmbuf); 587 588 avl_destroy(&zv->zv_znode.z_range_avl); 589 mutex_destroy(&zv->zv_znode.z_range_lock); 590 591 kmem_free(zv, sizeof (zvol_state_t)); 592 593 ddi_soft_state_free(zfsdev_state, minor); 594 595 zvol_minors--; 596 return (0); 597 } 598 599 int 600 zvol_remove_minor(const char *name) 601 { 602 zvol_state_t *zv; 603 int rc; 604 605 mutex_enter(&zfsdev_state_lock); 606 if ((zv = zvol_minor_lookup(name)) == NULL) { 607 mutex_exit(&zfsdev_state_lock); 608 return (SET_ERROR(ENXIO)); 609 } 610 rc = zvol_remove_zv(zv); 611 mutex_exit(&zfsdev_state_lock); 612 return (rc); 613 } 614 615 int 616 zvol_first_open(zvol_state_t *zv) 617 { 618 objset_t *os; 619 uint64_t volsize; 620 int error; 621 uint64_t readonly; 622 623 /* lie and say we're read-only */ 624 error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, B_TRUE, 625 zvol_tag, &os); 626 if (error) 627 return (error); 628 629 zv->zv_objset = os; 630 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize); 631 if (error) { 632 ASSERT(error == 0); 633 dmu_objset_disown(os, zvol_tag); 634 return (error); 635 } 636 637 error = dmu_bonus_hold(os, ZVOL_OBJ, zvol_tag, &zv->zv_dbuf); 638 if (error) { 639 dmu_objset_disown(os, zvol_tag); 640 return (error); 641 } 642 643 zvol_size_changed(zv, volsize); 644 zv->zv_zilog = zil_open(os, zvol_get_data); 645 646 VERIFY(dsl_prop_get_integer(zv->zv_name, "readonly", &readonly, 647 NULL) == 0); 648 if (readonly || dmu_objset_is_snapshot(os) || 649 !spa_writeable(dmu_objset_spa(os))) 650 zv->zv_flags |= ZVOL_RDONLY; 651 else 652 zv->zv_flags &= ~ZVOL_RDONLY; 653 return (error); 654 } 655 656 void 657 zvol_last_close(zvol_state_t *zv) 658 { 659 zil_close(zv->zv_zilog); 660 zv->zv_zilog = NULL; 661 662 dmu_buf_rele(zv->zv_dbuf, zvol_tag); 663 zv->zv_dbuf = NULL; 664 665 /* 666 * Evict cached data 667 */ 668 if (dsl_dataset_is_dirty(dmu_objset_ds(zv->zv_objset)) && 669 !(zv->zv_flags & ZVOL_RDONLY)) 670 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 671 dmu_objset_evict_dbufs(zv->zv_objset); 672 673 dmu_objset_disown(zv->zv_objset, zvol_tag); 674 zv->zv_objset = NULL; 675 } 676 677 int 678 zvol_prealloc(zvol_state_t *zv) 679 { 680 objset_t *os = zv->zv_objset; 681 dmu_tx_t *tx; 682 uint64_t refd, avail, usedobjs, availobjs; 683 uint64_t resid = zv->zv_volsize; 684 uint64_t off = 0; 685 686 /* Check the space usage before attempting to allocate the space */ 687 dmu_objset_space(os, &refd, &avail, &usedobjs, &availobjs); 688 if (avail < zv->zv_volsize) 689 return (SET_ERROR(ENOSPC)); 690 691 /* Free old extents if they exist */ 692 zvol_free_extents(zv); 693 694 while (resid != 0) { 695 int error; 696 uint64_t bytes = MIN(resid, SPA_OLD_MAXBLOCKSIZE); 697 698 tx = dmu_tx_create(os); 699 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes); 700 error = dmu_tx_assign(tx, TXG_WAIT); 701 if (error) { 702 dmu_tx_abort(tx); 703 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, off); 704 return (error); 705 } 706 dmu_prealloc(os, ZVOL_OBJ, off, bytes, tx); 707 dmu_tx_commit(tx); 708 off += bytes; 709 resid -= bytes; 710 } 711 txg_wait_synced(dmu_objset_pool(os), 0); 712 713 return (0); 714 } 715 716 static int 717 zvol_update_volsize(objset_t *os, uint64_t volsize) 718 { 719 dmu_tx_t *tx; 720 int error; 721 722 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 723 724 tx = dmu_tx_create(os); 725 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 726 dmu_tx_mark_netfree(tx); 727 error = dmu_tx_assign(tx, TXG_WAIT); 728 if (error) { 729 dmu_tx_abort(tx); 730 return (error); 731 } 732 733 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, 734 &volsize, tx); 735 dmu_tx_commit(tx); 736 737 if (error == 0) 738 error = dmu_free_long_range(os, 739 ZVOL_OBJ, volsize, DMU_OBJECT_END); 740 return (error); 741 } 742 743 void 744 zvol_remove_minors(const char *name) 745 { 746 zvol_state_t *zv; 747 char *namebuf; 748 minor_t minor; 749 750 namebuf = kmem_zalloc(strlen(name) + 2, KM_SLEEP); 751 (void) strncpy(namebuf, name, strlen(name)); 752 (void) strcat(namebuf, "/"); 753 mutex_enter(&zfsdev_state_lock); 754 for (minor = 1; minor <= ZFSDEV_MAX_MINOR; minor++) { 755 756 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 757 if (zv == NULL) 758 continue; 759 if (strncmp(namebuf, zv->zv_name, strlen(namebuf)) == 0) 760 (void) zvol_remove_zv(zv); 761 } 762 kmem_free(namebuf, strlen(name) + 2); 763 764 mutex_exit(&zfsdev_state_lock); 765 } 766 767 static int 768 zvol_update_live_volsize(zvol_state_t *zv, uint64_t volsize) 769 { 770 uint64_t old_volsize = 0ULL; 771 int error = 0; 772 773 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 774 775 /* 776 * Reinitialize the dump area to the new size. If we 777 * failed to resize the dump area then restore it back to 778 * its original size. We must set the new volsize prior 779 * to calling dumpvp_resize() to ensure that the devices' 780 * size(9P) is not visible by the dump subsystem. 781 */ 782 old_volsize = zv->zv_volsize; 783 zvol_size_changed(zv, volsize); 784 785 if (zv->zv_flags & ZVOL_DUMPIFIED) { 786 if ((error = zvol_dumpify(zv)) != 0 || 787 (error = dumpvp_resize()) != 0) { 788 int dumpify_error; 789 790 (void) zvol_update_volsize(zv->zv_objset, old_volsize); 791 zvol_size_changed(zv, old_volsize); 792 dumpify_error = zvol_dumpify(zv); 793 error = dumpify_error ? dumpify_error : error; 794 } 795 } 796 797 /* 798 * Generate a LUN expansion event. 799 */ 800 if (error == 0) { 801 sysevent_id_t eid; 802 nvlist_t *attr; 803 char *physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 804 805 (void) snprintf(physpath, MAXPATHLEN, "%s%u", ZVOL_PSEUDO_DEV, 806 zv->zv_minor); 807 808 VERIFY(nvlist_alloc(&attr, NV_UNIQUE_NAME, KM_SLEEP) == 0); 809 VERIFY(nvlist_add_string(attr, DEV_PHYS_PATH, physpath) == 0); 810 811 (void) ddi_log_sysevent(zfs_dip, SUNW_VENDOR, EC_DEV_STATUS, 812 ESC_DEV_DLE, attr, &eid, DDI_SLEEP); 813 814 nvlist_free(attr); 815 kmem_free(physpath, MAXPATHLEN); 816 } 817 return (error); 818 } 819 820 int 821 zvol_set_volsize(const char *name, uint64_t volsize) 822 { 823 zvol_state_t *zv = NULL; 824 objset_t *os; 825 int error; 826 dmu_object_info_t doi; 827 uint64_t readonly; 828 boolean_t owned = B_FALSE; 829 830 error = dsl_prop_get_integer(name, 831 zfs_prop_to_name(ZFS_PROP_READONLY), &readonly, NULL); 832 if (error != 0) 833 return (error); 834 if (readonly) 835 return (SET_ERROR(EROFS)); 836 837 mutex_enter(&zfsdev_state_lock); 838 zv = zvol_minor_lookup(name); 839 840 if (zv == NULL || zv->zv_objset == NULL) { 841 if ((error = dmu_objset_own(name, DMU_OST_ZVOL, B_FALSE, 842 FTAG, &os)) != 0) { 843 mutex_exit(&zfsdev_state_lock); 844 return (error); 845 } 846 owned = B_TRUE; 847 if (zv != NULL) 848 zv->zv_objset = os; 849 } else { 850 os = zv->zv_objset; 851 } 852 853 if ((error = dmu_object_info(os, ZVOL_OBJ, &doi)) != 0 || 854 (error = zvol_check_volsize(volsize, doi.doi_data_block_size)) != 0) 855 goto out; 856 857 error = zvol_update_volsize(os, volsize); 858 859 if (error == 0 && zv != NULL) 860 error = zvol_update_live_volsize(zv, volsize); 861 out: 862 if (owned) { 863 dmu_objset_disown(os, FTAG); 864 if (zv != NULL) 865 zv->zv_objset = NULL; 866 } 867 mutex_exit(&zfsdev_state_lock); 868 return (error); 869 } 870 871 /*ARGSUSED*/ 872 int 873 zvol_open(dev_t *devp, int flag, int otyp, cred_t *cr) 874 { 875 zvol_state_t *zv; 876 int err = 0; 877 878 mutex_enter(&zfsdev_state_lock); 879 880 zv = zfsdev_get_soft_state(getminor(*devp), ZSST_ZVOL); 881 if (zv == NULL) { 882 mutex_exit(&zfsdev_state_lock); 883 return (SET_ERROR(ENXIO)); 884 } 885 886 if (zv->zv_total_opens == 0) 887 err = zvol_first_open(zv); 888 if (err) { 889 mutex_exit(&zfsdev_state_lock); 890 return (err); 891 } 892 if ((flag & FWRITE) && (zv->zv_flags & ZVOL_RDONLY)) { 893 err = SET_ERROR(EROFS); 894 goto out; 895 } 896 if (zv->zv_flags & ZVOL_EXCL) { 897 err = SET_ERROR(EBUSY); 898 goto out; 899 } 900 if (flag & FEXCL) { 901 if (zv->zv_total_opens != 0) { 902 err = SET_ERROR(EBUSY); 903 goto out; 904 } 905 zv->zv_flags |= ZVOL_EXCL; 906 } 907 908 if (zv->zv_open_count[otyp] == 0 || otyp == OTYP_LYR) { 909 zv->zv_open_count[otyp]++; 910 zv->zv_total_opens++; 911 } 912 mutex_exit(&zfsdev_state_lock); 913 914 return (err); 915 out: 916 if (zv->zv_total_opens == 0) 917 zvol_last_close(zv); 918 mutex_exit(&zfsdev_state_lock); 919 return (err); 920 } 921 922 /*ARGSUSED*/ 923 int 924 zvol_close(dev_t dev, int flag, int otyp, cred_t *cr) 925 { 926 minor_t minor = getminor(dev); 927 zvol_state_t *zv; 928 int error = 0; 929 930 mutex_enter(&zfsdev_state_lock); 931 932 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 933 if (zv == NULL) { 934 mutex_exit(&zfsdev_state_lock); 935 return (SET_ERROR(ENXIO)); 936 } 937 938 if (zv->zv_flags & ZVOL_EXCL) { 939 ASSERT(zv->zv_total_opens == 1); 940 zv->zv_flags &= ~ZVOL_EXCL; 941 } 942 943 /* 944 * If the open count is zero, this is a spurious close. 945 * That indicates a bug in the kernel / DDI framework. 946 */ 947 ASSERT(zv->zv_open_count[otyp] != 0); 948 ASSERT(zv->zv_total_opens != 0); 949 950 /* 951 * You may get multiple opens, but only one close. 952 */ 953 zv->zv_open_count[otyp]--; 954 zv->zv_total_opens--; 955 956 if (zv->zv_total_opens == 0) 957 zvol_last_close(zv); 958 959 mutex_exit(&zfsdev_state_lock); 960 return (error); 961 } 962 963 static void 964 zvol_get_done(zgd_t *zgd, int error) 965 { 966 if (zgd->zgd_db) 967 dmu_buf_rele(zgd->zgd_db, zgd); 968 969 zfs_range_unlock(zgd->zgd_rl); 970 971 if (error == 0 && zgd->zgd_bp) 972 zil_add_block(zgd->zgd_zilog, zgd->zgd_bp); 973 974 kmem_free(zgd, sizeof (zgd_t)); 975 } 976 977 /* 978 * Get data to generate a TX_WRITE intent log record. 979 */ 980 static int 981 zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio) 982 { 983 zvol_state_t *zv = arg; 984 objset_t *os = zv->zv_objset; 985 uint64_t object = ZVOL_OBJ; 986 uint64_t offset = lr->lr_offset; 987 uint64_t size = lr->lr_length; /* length of user data */ 988 blkptr_t *bp = &lr->lr_blkptr; 989 dmu_buf_t *db; 990 zgd_t *zgd; 991 int error; 992 993 ASSERT(zio != NULL); 994 ASSERT(size != 0); 995 996 zgd = kmem_zalloc(sizeof (zgd_t), KM_SLEEP); 997 zgd->zgd_zilog = zv->zv_zilog; 998 zgd->zgd_rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER); 999 1000 /* 1001 * Write records come in two flavors: immediate and indirect. 1002 * For small writes it's cheaper to store the data with the 1003 * log record (immediate); for large writes it's cheaper to 1004 * sync the data and get a pointer to it (indirect) so that 1005 * we don't have to write the data twice. 1006 */ 1007 if (buf != NULL) { /* immediate write */ 1008 error = dmu_read(os, object, offset, size, buf, 1009 DMU_READ_NO_PREFETCH); 1010 } else { 1011 size = zv->zv_volblocksize; 1012 offset = P2ALIGN(offset, size); 1013 error = dmu_buf_hold(os, object, offset, zgd, &db, 1014 DMU_READ_NO_PREFETCH); 1015 if (error == 0) { 1016 blkptr_t *obp = dmu_buf_get_blkptr(db); 1017 if (obp) { 1018 ASSERT(BP_IS_HOLE(bp)); 1019 *bp = *obp; 1020 } 1021 1022 zgd->zgd_db = db; 1023 zgd->zgd_bp = bp; 1024 1025 ASSERT(db->db_offset == offset); 1026 ASSERT(db->db_size == size); 1027 1028 error = dmu_sync(zio, lr->lr_common.lrc_txg, 1029 zvol_get_done, zgd); 1030 1031 if (error == 0) 1032 return (0); 1033 } 1034 } 1035 1036 zvol_get_done(zgd, error); 1037 1038 return (error); 1039 } 1040 1041 /* 1042 * zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions. 1043 * 1044 * We store data in the log buffers if it's small enough. 1045 * Otherwise we will later flush the data out via dmu_sync(). 1046 */ 1047 ssize_t zvol_immediate_write_sz = 32768; 1048 1049 static void 1050 zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, offset_t off, ssize_t resid, 1051 boolean_t sync) 1052 { 1053 uint32_t blocksize = zv->zv_volblocksize; 1054 zilog_t *zilog = zv->zv_zilog; 1055 boolean_t slogging; 1056 ssize_t immediate_write_sz; 1057 1058 if (zil_replaying(zilog, tx)) 1059 return; 1060 1061 immediate_write_sz = (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT) 1062 ? 0 : zvol_immediate_write_sz; 1063 1064 slogging = spa_has_slogs(zilog->zl_spa) && 1065 (zilog->zl_logbias == ZFS_LOGBIAS_LATENCY); 1066 1067 while (resid) { 1068 itx_t *itx; 1069 lr_write_t *lr; 1070 ssize_t len; 1071 itx_wr_state_t write_state; 1072 1073 /* 1074 * Unlike zfs_log_write() we can be called with 1075 * upto DMU_MAX_ACCESS/2 (5MB) writes. 1076 */ 1077 if (blocksize > immediate_write_sz && !slogging && 1078 resid >= blocksize && off % blocksize == 0) { 1079 write_state = WR_INDIRECT; /* uses dmu_sync */ 1080 len = blocksize; 1081 } else if (sync) { 1082 write_state = WR_COPIED; 1083 len = MIN(ZIL_MAX_LOG_DATA, resid); 1084 } else { 1085 write_state = WR_NEED_COPY; 1086 len = MIN(ZIL_MAX_LOG_DATA, resid); 1087 } 1088 1089 itx = zil_itx_create(TX_WRITE, sizeof (*lr) + 1090 (write_state == WR_COPIED ? len : 0)); 1091 lr = (lr_write_t *)&itx->itx_lr; 1092 if (write_state == WR_COPIED && dmu_read(zv->zv_objset, 1093 ZVOL_OBJ, off, len, lr + 1, DMU_READ_NO_PREFETCH) != 0) { 1094 zil_itx_destroy(itx); 1095 itx = zil_itx_create(TX_WRITE, sizeof (*lr)); 1096 lr = (lr_write_t *)&itx->itx_lr; 1097 write_state = WR_NEED_COPY; 1098 } 1099 1100 itx->itx_wr_state = write_state; 1101 if (write_state == WR_NEED_COPY) 1102 itx->itx_sod += len; 1103 lr->lr_foid = ZVOL_OBJ; 1104 lr->lr_offset = off; 1105 lr->lr_length = len; 1106 lr->lr_blkoff = 0; 1107 BP_ZERO(&lr->lr_blkptr); 1108 1109 itx->itx_private = zv; 1110 itx->itx_sync = sync; 1111 1112 zil_itx_assign(zilog, itx, tx); 1113 1114 rw_enter(&rz_zev_rwlock, RW_READER); 1115 if (rz_zev_callbacks && rz_zev_callbacks->rz_zev_zvol_write) 1116 rz_zev_callbacks->rz_zev_zvol_write(zv->zv_name, 1117 zv->zv_objset, tx, off, len); 1118 rw_exit(&rz_zev_rwlock); 1119 1120 off += len; 1121 resid -= len; 1122 } 1123 } 1124 1125 static int 1126 zvol_dumpio_vdev(vdev_t *vd, void *addr, uint64_t offset, uint64_t origoffset, 1127 uint64_t size, boolean_t doread, boolean_t isdump) 1128 { 1129 vdev_disk_t *dvd; 1130 int c; 1131 int numerrors = 0; 1132 1133 if (vd->vdev_ops == &vdev_mirror_ops || 1134 vd->vdev_ops == &vdev_replacing_ops || 1135 vd->vdev_ops == &vdev_spare_ops) { 1136 for (c = 0; c < vd->vdev_children; c++) { 1137 int err = zvol_dumpio_vdev(vd->vdev_child[c], 1138 addr, offset, origoffset, size, doread, isdump); 1139 if (err != 0) { 1140 numerrors++; 1141 } else if (doread) { 1142 break; 1143 } 1144 } 1145 } 1146 1147 if (!vd->vdev_ops->vdev_op_leaf && vd->vdev_ops != &vdev_raidz_ops) 1148 return (numerrors < vd->vdev_children ? 0 : EIO); 1149 1150 if (doread && !vdev_readable(vd)) 1151 return (SET_ERROR(EIO)); 1152 else if (!doread && !vdev_writeable(vd)) 1153 return (SET_ERROR(EIO)); 1154 1155 if (vd->vdev_ops == &vdev_raidz_ops) { 1156 return (vdev_raidz_physio(vd, 1157 addr, size, offset, origoffset, doread, isdump)); 1158 } 1159 1160 offset += VDEV_LABEL_START_SIZE; 1161 1162 if (ddi_in_panic() || isdump) { 1163 ASSERT(!doread); 1164 if (doread) 1165 return (SET_ERROR(EIO)); 1166 dvd = vd->vdev_tsd; 1167 ASSERT3P(dvd, !=, NULL); 1168 return (ldi_dump(dvd->vd_lh, addr, lbtodb(offset), 1169 lbtodb(size))); 1170 } else { 1171 dvd = vd->vdev_tsd; 1172 ASSERT3P(dvd, !=, NULL); 1173 return (vdev_disk_ldi_physio(dvd->vd_lh, addr, size, 1174 offset, doread ? B_READ : B_WRITE)); 1175 } 1176 } 1177 1178 static int 1179 zvol_dumpio(zvol_state_t *zv, void *addr, uint64_t offset, uint64_t size, 1180 boolean_t doread, boolean_t isdump) 1181 { 1182 vdev_t *vd; 1183 int error; 1184 zvol_extent_t *ze; 1185 spa_t *spa = dmu_objset_spa(zv->zv_objset); 1186 1187 /* Must be sector aligned, and not stradle a block boundary. */ 1188 if (P2PHASE(offset, DEV_BSIZE) || P2PHASE(size, DEV_BSIZE) || 1189 P2BOUNDARY(offset, size, zv->zv_volblocksize)) { 1190 return (SET_ERROR(EINVAL)); 1191 } 1192 ASSERT(size <= zv->zv_volblocksize); 1193 1194 /* Locate the extent this belongs to */ 1195 ze = list_head(&zv->zv_extents); 1196 while (offset >= ze->ze_nblks * zv->zv_volblocksize) { 1197 offset -= ze->ze_nblks * zv->zv_volblocksize; 1198 ze = list_next(&zv->zv_extents, ze); 1199 } 1200 1201 if (ze == NULL) 1202 return (SET_ERROR(EINVAL)); 1203 1204 if (!ddi_in_panic()) 1205 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER); 1206 1207 vd = vdev_lookup_top(spa, DVA_GET_VDEV(&ze->ze_dva)); 1208 offset += DVA_GET_OFFSET(&ze->ze_dva); 1209 error = zvol_dumpio_vdev(vd, addr, offset, DVA_GET_OFFSET(&ze->ze_dva), 1210 size, doread, isdump); 1211 1212 if (!ddi_in_panic()) 1213 spa_config_exit(spa, SCL_STATE, FTAG); 1214 1215 return (error); 1216 } 1217 1218 int 1219 zvol_strategy(buf_t *bp) 1220 { 1221 zfs_soft_state_t *zs = NULL; 1222 zvol_state_t *zv; 1223 uint64_t off, volsize; 1224 size_t resid; 1225 char *addr; 1226 objset_t *os; 1227 rl_t *rl; 1228 int error = 0; 1229 boolean_t doread = bp->b_flags & B_READ; 1230 boolean_t is_dumpified; 1231 boolean_t sync; 1232 1233 if (getminor(bp->b_edev) == 0) { 1234 error = SET_ERROR(EINVAL); 1235 } else { 1236 zs = ddi_get_soft_state(zfsdev_state, getminor(bp->b_edev)); 1237 if (zs == NULL) 1238 error = SET_ERROR(ENXIO); 1239 else if (zs->zss_type != ZSST_ZVOL) 1240 error = SET_ERROR(EINVAL); 1241 } 1242 1243 if (error) { 1244 bioerror(bp, error); 1245 biodone(bp); 1246 return (0); 1247 } 1248 1249 zv = zs->zss_data; 1250 1251 if (!(bp->b_flags & B_READ) && (zv->zv_flags & ZVOL_RDONLY)) { 1252 bioerror(bp, EROFS); 1253 biodone(bp); 1254 return (0); 1255 } 1256 1257 off = ldbtob(bp->b_blkno); 1258 volsize = zv->zv_volsize; 1259 1260 os = zv->zv_objset; 1261 ASSERT(os != NULL); 1262 1263 bp_mapin(bp); 1264 addr = bp->b_un.b_addr; 1265 resid = bp->b_bcount; 1266 1267 if (resid > 0 && (off < 0 || off >= volsize)) { 1268 bioerror(bp, EIO); 1269 biodone(bp); 1270 return (0); 1271 } 1272 1273 is_dumpified = zv->zv_flags & ZVOL_DUMPIFIED; 1274 sync = ((!(bp->b_flags & B_ASYNC) && 1275 !(zv->zv_flags & ZVOL_WCE)) || 1276 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)) && 1277 !doread && !is_dumpified; 1278 1279 /* 1280 * There must be no buffer changes when doing a dmu_sync() because 1281 * we can't change the data whilst calculating the checksum. 1282 */ 1283 rl = zfs_range_lock(&zv->zv_znode, off, resid, 1284 doread ? RL_READER : RL_WRITER); 1285 1286 while (resid != 0 && off < volsize) { 1287 size_t size = MIN(resid, zvol_maxphys); 1288 if (is_dumpified) { 1289 size = MIN(size, P2END(off, zv->zv_volblocksize) - off); 1290 error = zvol_dumpio(zv, addr, off, size, 1291 doread, B_FALSE); 1292 } else if (doread) { 1293 error = dmu_read(os, ZVOL_OBJ, off, size, addr, 1294 DMU_READ_PREFETCH); 1295 } else { 1296 dmu_tx_t *tx = dmu_tx_create(os); 1297 dmu_tx_hold_write(tx, ZVOL_OBJ, off, size); 1298 error = dmu_tx_assign(tx, TXG_WAIT); 1299 if (error) { 1300 dmu_tx_abort(tx); 1301 } else { 1302 dmu_write(os, ZVOL_OBJ, off, size, addr, tx); 1303 zvol_log_write(zv, tx, off, size, sync); 1304 dmu_tx_commit(tx); 1305 } 1306 } 1307 if (error) { 1308 /* convert checksum errors into IO errors */ 1309 if (error == ECKSUM) 1310 error = SET_ERROR(EIO); 1311 break; 1312 } 1313 off += size; 1314 addr += size; 1315 resid -= size; 1316 } 1317 zfs_range_unlock(rl); 1318 1319 if ((bp->b_resid = resid) == bp->b_bcount) 1320 bioerror(bp, off > volsize ? EINVAL : error); 1321 1322 if (sync) 1323 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1324 biodone(bp); 1325 1326 return (0); 1327 } 1328 1329 /* 1330 * Set the buffer count to the zvol maximum transfer. 1331 * Using our own routine instead of the default minphys() 1332 * means that for larger writes we write bigger buffers on X86 1333 * (128K instead of 56K) and flush the disk write cache less often 1334 * (every zvol_maxphys - currently 1MB) instead of minphys (currently 1335 * 56K on X86 and 128K on sparc). 1336 */ 1337 void 1338 zvol_minphys(struct buf *bp) 1339 { 1340 if (bp->b_bcount > zvol_maxphys) 1341 bp->b_bcount = zvol_maxphys; 1342 } 1343 1344 int 1345 zvol_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblocks) 1346 { 1347 minor_t minor = getminor(dev); 1348 zvol_state_t *zv; 1349 int error = 0; 1350 uint64_t size; 1351 uint64_t boff; 1352 uint64_t resid; 1353 1354 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1355 if (zv == NULL) 1356 return (SET_ERROR(ENXIO)); 1357 1358 if ((zv->zv_flags & ZVOL_DUMPIFIED) == 0) 1359 return (SET_ERROR(EINVAL)); 1360 1361 boff = ldbtob(blkno); 1362 resid = ldbtob(nblocks); 1363 1364 VERIFY3U(boff + resid, <=, zv->zv_volsize); 1365 1366 while (resid) { 1367 size = MIN(resid, P2END(boff, zv->zv_volblocksize) - boff); 1368 error = zvol_dumpio(zv, addr, boff, size, B_FALSE, B_TRUE); 1369 if (error) 1370 break; 1371 boff += size; 1372 addr += size; 1373 resid -= size; 1374 } 1375 1376 return (error); 1377 } 1378 1379 /*ARGSUSED*/ 1380 int 1381 zvol_read(dev_t dev, uio_t *uio, cred_t *cr) 1382 { 1383 minor_t minor = getminor(dev); 1384 zvol_state_t *zv; 1385 uint64_t volsize; 1386 rl_t *rl; 1387 int error = 0; 1388 1389 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1390 if (zv == NULL) 1391 return (SET_ERROR(ENXIO)); 1392 1393 volsize = zv->zv_volsize; 1394 if (uio->uio_resid > 0 && 1395 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize)) 1396 return (SET_ERROR(EIO)); 1397 1398 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1399 error = physio(zvol_strategy, NULL, dev, B_READ, 1400 zvol_minphys, uio); 1401 return (error); 1402 } 1403 1404 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid, 1405 RL_READER); 1406 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1407 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1408 1409 /* don't read past the end */ 1410 if (bytes > volsize - uio->uio_loffset) 1411 bytes = volsize - uio->uio_loffset; 1412 1413 error = dmu_read_uio(zv->zv_objset, ZVOL_OBJ, uio, bytes); 1414 if (error) { 1415 /* convert checksum errors into IO errors */ 1416 if (error == ECKSUM) 1417 error = SET_ERROR(EIO); 1418 break; 1419 } 1420 } 1421 zfs_range_unlock(rl); 1422 return (error); 1423 } 1424 1425 /*ARGSUSED*/ 1426 int 1427 zvol_write(dev_t dev, uio_t *uio, cred_t *cr) 1428 { 1429 minor_t minor = getminor(dev); 1430 zvol_state_t *zv; 1431 uint64_t volsize; 1432 rl_t *rl; 1433 int error = 0; 1434 boolean_t sync; 1435 1436 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1437 if (zv == NULL) 1438 return (SET_ERROR(ENXIO)); 1439 1440 volsize = zv->zv_volsize; 1441 if (uio->uio_resid > 0 && 1442 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize)) 1443 return (SET_ERROR(EIO)); 1444 1445 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1446 error = physio(zvol_strategy, NULL, dev, B_WRITE, 1447 zvol_minphys, uio); 1448 return (error); 1449 } 1450 1451 sync = !(zv->zv_flags & ZVOL_WCE) || 1452 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS); 1453 1454 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid, 1455 RL_WRITER); 1456 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1457 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1458 uint64_t off = uio->uio_loffset; 1459 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset); 1460 1461 if (bytes > volsize - off) /* don't write past the end */ 1462 bytes = volsize - off; 1463 1464 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes); 1465 error = dmu_tx_assign(tx, TXG_WAIT); 1466 if (error) { 1467 dmu_tx_abort(tx); 1468 break; 1469 } 1470 error = dmu_write_uio_dbuf(zv->zv_dbuf, uio, bytes, tx); 1471 if (error == 0) 1472 zvol_log_write(zv, tx, off, bytes, sync); 1473 dmu_tx_commit(tx); 1474 1475 if (error) 1476 break; 1477 } 1478 zfs_range_unlock(rl); 1479 if (sync) 1480 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1481 return (error); 1482 } 1483 1484 int 1485 zvol_getefi(void *arg, int flag, uint64_t vs, uint8_t bs) 1486 { 1487 struct uuid uuid = EFI_RESERVED; 1488 efi_gpe_t gpe = { 0 }; 1489 uint32_t crc; 1490 dk_efi_t efi; 1491 int length; 1492 char *ptr; 1493 1494 if (ddi_copyin(arg, &efi, sizeof (dk_efi_t), flag)) 1495 return (SET_ERROR(EFAULT)); 1496 ptr = (char *)(uintptr_t)efi.dki_data_64; 1497 length = efi.dki_length; 1498 /* 1499 * Some clients may attempt to request a PMBR for the 1500 * zvol. Currently this interface will return EINVAL to 1501 * such requests. These requests could be supported by 1502 * adding a check for lba == 0 and consing up an appropriate 1503 * PMBR. 1504 */ 1505 if (efi.dki_lba < 1 || efi.dki_lba > 2 || length <= 0) 1506 return (SET_ERROR(EINVAL)); 1507 1508 gpe.efi_gpe_StartingLBA = LE_64(34ULL); 1509 gpe.efi_gpe_EndingLBA = LE_64((vs >> bs) - 1); 1510 UUID_LE_CONVERT(gpe.efi_gpe_PartitionTypeGUID, uuid); 1511 1512 if (efi.dki_lba == 1) { 1513 efi_gpt_t gpt = { 0 }; 1514 1515 gpt.efi_gpt_Signature = LE_64(EFI_SIGNATURE); 1516 gpt.efi_gpt_Revision = LE_32(EFI_VERSION_CURRENT); 1517 gpt.efi_gpt_HeaderSize = LE_32(sizeof (gpt)); 1518 gpt.efi_gpt_MyLBA = LE_64(1ULL); 1519 gpt.efi_gpt_FirstUsableLBA = LE_64(34ULL); 1520 gpt.efi_gpt_LastUsableLBA = LE_64((vs >> bs) - 1); 1521 gpt.efi_gpt_PartitionEntryLBA = LE_64(2ULL); 1522 gpt.efi_gpt_NumberOfPartitionEntries = LE_32(1); 1523 gpt.efi_gpt_SizeOfPartitionEntry = 1524 LE_32(sizeof (efi_gpe_t)); 1525 CRC32(crc, &gpe, sizeof (gpe), -1U, crc32_table); 1526 gpt.efi_gpt_PartitionEntryArrayCRC32 = LE_32(~crc); 1527 CRC32(crc, &gpt, sizeof (gpt), -1U, crc32_table); 1528 gpt.efi_gpt_HeaderCRC32 = LE_32(~crc); 1529 if (ddi_copyout(&gpt, ptr, MIN(sizeof (gpt), length), 1530 flag)) 1531 return (SET_ERROR(EFAULT)); 1532 ptr += sizeof (gpt); 1533 length -= sizeof (gpt); 1534 } 1535 if (length > 0 && ddi_copyout(&gpe, ptr, MIN(sizeof (gpe), 1536 length), flag)) 1537 return (SET_ERROR(EFAULT)); 1538 return (0); 1539 } 1540 1541 /* 1542 * BEGIN entry points to allow external callers access to the volume. 1543 */ 1544 /* 1545 * Return the volume parameters needed for access from an external caller. 1546 * These values are invariant as long as the volume is held open. 1547 */ 1548 int 1549 zvol_get_volume_params(minor_t minor, uint64_t *blksize, 1550 uint64_t *max_xfer_len, void **minor_hdl, void **objset_hdl, void **zil_hdl, 1551 void **rl_hdl, void **bonus_hdl) 1552 { 1553 zvol_state_t *zv; 1554 1555 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1556 if (zv == NULL) 1557 return (SET_ERROR(ENXIO)); 1558 if (zv->zv_flags & ZVOL_DUMPIFIED) 1559 return (SET_ERROR(ENXIO)); 1560 1561 ASSERT(blksize && max_xfer_len && minor_hdl && 1562 objset_hdl && zil_hdl && rl_hdl && bonus_hdl); 1563 1564 *blksize = zv->zv_volblocksize; 1565 *max_xfer_len = (uint64_t)zvol_maxphys; 1566 *minor_hdl = zv; 1567 *objset_hdl = zv->zv_objset; 1568 *zil_hdl = zv->zv_zilog; 1569 *rl_hdl = &zv->zv_znode; 1570 *bonus_hdl = zv->zv_dbuf; 1571 return (0); 1572 } 1573 1574 /* 1575 * Return the current volume size to an external caller. 1576 * The size can change while the volume is open. 1577 */ 1578 uint64_t 1579 zvol_get_volume_size(void *minor_hdl) 1580 { 1581 zvol_state_t *zv = minor_hdl; 1582 1583 return (zv->zv_volsize); 1584 } 1585 1586 /* 1587 * Return the current WCE setting to an external caller. 1588 * The WCE setting can change while the volume is open. 1589 */ 1590 int 1591 zvol_get_volume_wce(void *minor_hdl) 1592 { 1593 zvol_state_t *zv = minor_hdl; 1594 1595 return ((zv->zv_flags & ZVOL_WCE) ? 1 : 0); 1596 } 1597 1598 /* 1599 * Entry point for external callers to zvol_log_write 1600 */ 1601 void 1602 zvol_log_write_minor(void *minor_hdl, dmu_tx_t *tx, offset_t off, ssize_t resid, 1603 boolean_t sync) 1604 { 1605 zvol_state_t *zv = minor_hdl; 1606 1607 zvol_log_write(zv, tx, off, resid, sync); 1608 } 1609 /* 1610 * END entry points to allow external callers access to the volume. 1611 */ 1612 1613 /* 1614 * Log a DKIOCFREE/free-long-range to the ZIL with TX_TRUNCATE. 1615 */ 1616 static void 1617 zvol_log_truncate(zvol_state_t *zv, dmu_tx_t *tx, uint64_t off, uint64_t len, 1618 boolean_t sync) 1619 { 1620 itx_t *itx; 1621 lr_truncate_t *lr; 1622 zilog_t *zilog = zv->zv_zilog; 1623 1624 if (zil_replaying(zilog, tx)) 1625 return; 1626 1627 itx = zil_itx_create(TX_TRUNCATE, sizeof (*lr)); 1628 lr = (lr_truncate_t *)&itx->itx_lr; 1629 lr->lr_foid = ZVOL_OBJ; 1630 lr->lr_offset = off; 1631 lr->lr_length = len; 1632 1633 itx->itx_sync = sync; 1634 zil_itx_assign(zilog, itx, tx); 1635 1636 rw_enter(&rz_zev_rwlock, RW_READER); 1637 if (rz_zev_callbacks && rz_zev_callbacks->rz_zev_zvol_truncate) 1638 rz_zev_callbacks->rz_zev_zvol_truncate(zv->zv_name, 1639 zv->zv_objset, tx, off, len); 1640 rw_exit(&rz_zev_rwlock); 1641 } 1642 1643 /* 1644 * Dirtbag ioctls to support mkfs(1M) for UFS filesystems. See dkio(7I). 1645 * Also a dirtbag dkio ioctl for unmap/free-block functionality. 1646 */ 1647 /*ARGSUSED*/ 1648 int 1649 zvol_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp) 1650 { 1651 zvol_state_t *zv; 1652 struct dk_callback *dkc; 1653 int error = 0; 1654 rl_t *rl; 1655 1656 mutex_enter(&zfsdev_state_lock); 1657 1658 zv = zfsdev_get_soft_state(getminor(dev), ZSST_ZVOL); 1659 1660 if (zv == NULL) { 1661 mutex_exit(&zfsdev_state_lock); 1662 return (SET_ERROR(ENXIO)); 1663 } 1664 ASSERT(zv->zv_total_opens > 0); 1665 1666 switch (cmd) { 1667 1668 case DKIOCINFO: 1669 { 1670 struct dk_cinfo dki; 1671 1672 bzero(&dki, sizeof (dki)); 1673 (void) strcpy(dki.dki_cname, "zvol"); 1674 (void) strcpy(dki.dki_dname, "zvol"); 1675 dki.dki_ctype = DKC_UNKNOWN; 1676 dki.dki_unit = getminor(dev); 1677 dki.dki_maxtransfer = 1678 1 << (SPA_OLD_MAXBLOCKSHIFT - zv->zv_min_bs); 1679 mutex_exit(&zfsdev_state_lock); 1680 if (ddi_copyout(&dki, (void *)arg, sizeof (dki), flag)) 1681 error = SET_ERROR(EFAULT); 1682 return (error); 1683 } 1684 1685 case DKIOCGMEDIAINFO: 1686 { 1687 struct dk_minfo dkm; 1688 1689 bzero(&dkm, sizeof (dkm)); 1690 dkm.dki_lbsize = 1U << zv->zv_min_bs; 1691 dkm.dki_capacity = zv->zv_volsize >> zv->zv_min_bs; 1692 dkm.dki_media_type = DK_UNKNOWN; 1693 mutex_exit(&zfsdev_state_lock); 1694 if (ddi_copyout(&dkm, (void *)arg, sizeof (dkm), flag)) 1695 error = SET_ERROR(EFAULT); 1696 return (error); 1697 } 1698 1699 case DKIOCGMEDIAINFOEXT: 1700 { 1701 struct dk_minfo_ext dkmext; 1702 1703 bzero(&dkmext, sizeof (dkmext)); 1704 dkmext.dki_lbsize = 1U << zv->zv_min_bs; 1705 dkmext.dki_pbsize = zv->zv_volblocksize; 1706 dkmext.dki_capacity = zv->zv_volsize >> zv->zv_min_bs; 1707 dkmext.dki_media_type = DK_UNKNOWN; 1708 mutex_exit(&zfsdev_state_lock); 1709 if (ddi_copyout(&dkmext, (void *)arg, sizeof (dkmext), flag)) 1710 error = SET_ERROR(EFAULT); 1711 return (error); 1712 } 1713 1714 case DKIOCGETEFI: 1715 { 1716 uint64_t vs = zv->zv_volsize; 1717 uint8_t bs = zv->zv_min_bs; 1718 1719 mutex_exit(&zfsdev_state_lock); 1720 error = zvol_getefi((void *)arg, flag, vs, bs); 1721 return (error); 1722 } 1723 1724 case DKIOCFLUSHWRITECACHE: 1725 dkc = (struct dk_callback *)arg; 1726 mutex_exit(&zfsdev_state_lock); 1727 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1728 if ((flag & FKIOCTL) && dkc != NULL && dkc->dkc_callback) { 1729 (*dkc->dkc_callback)(dkc->dkc_cookie, error); 1730 error = 0; 1731 } 1732 return (error); 1733 1734 case DKIOCGETWCE: 1735 { 1736 int wce = (zv->zv_flags & ZVOL_WCE) ? 1 : 0; 1737 if (ddi_copyout(&wce, (void *)arg, sizeof (int), 1738 flag)) 1739 error = SET_ERROR(EFAULT); 1740 break; 1741 } 1742 case DKIOCSETWCE: 1743 { 1744 int wce; 1745 if (ddi_copyin((void *)arg, &wce, sizeof (int), 1746 flag)) { 1747 error = SET_ERROR(EFAULT); 1748 break; 1749 } 1750 if (wce) { 1751 zv->zv_flags |= ZVOL_WCE; 1752 mutex_exit(&zfsdev_state_lock); 1753 } else { 1754 zv->zv_flags &= ~ZVOL_WCE; 1755 mutex_exit(&zfsdev_state_lock); 1756 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1757 } 1758 return (0); 1759 } 1760 1761 case DKIOCGGEOM: 1762 case DKIOCGVTOC: 1763 /* 1764 * commands using these (like prtvtoc) expect ENOTSUP 1765 * since we're emulating an EFI label 1766 */ 1767 error = SET_ERROR(ENOTSUP); 1768 break; 1769 1770 case DKIOCDUMPINIT: 1771 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize, 1772 RL_WRITER); 1773 error = zvol_dumpify(zv); 1774 zfs_range_unlock(rl); 1775 break; 1776 1777 case DKIOCDUMPFINI: 1778 if (!(zv->zv_flags & ZVOL_DUMPIFIED)) 1779 break; 1780 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize, 1781 RL_WRITER); 1782 error = zvol_dump_fini(zv); 1783 zfs_range_unlock(rl); 1784 break; 1785 1786 case DKIOCFREE: 1787 { 1788 dkioc_free_t df; 1789 dmu_tx_t *tx; 1790 1791 if (!zvol_unmap_enabled) 1792 break; 1793 1794 if (ddi_copyin((void *)arg, &df, sizeof (df), flag)) { 1795 error = SET_ERROR(EFAULT); 1796 break; 1797 } 1798 1799 /* 1800 * Apply Postel's Law to length-checking. If they overshoot, 1801 * just blank out until the end, if there's a need to blank 1802 * out anything. 1803 */ 1804 if (df.df_start >= zv->zv_volsize) 1805 break; /* No need to do anything... */ 1806 1807 mutex_exit(&zfsdev_state_lock); 1808 1809 rl = zfs_range_lock(&zv->zv_znode, df.df_start, df.df_length, 1810 RL_WRITER); 1811 tx = dmu_tx_create(zv->zv_objset); 1812 dmu_tx_mark_netfree(tx); 1813 error = dmu_tx_assign(tx, TXG_WAIT); 1814 if (error != 0) { 1815 dmu_tx_abort(tx); 1816 } else { 1817 zvol_log_truncate(zv, tx, df.df_start, 1818 df.df_length, B_TRUE); 1819 dmu_tx_commit(tx); 1820 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 1821 df.df_start, df.df_length); 1822 } 1823 1824 zfs_range_unlock(rl); 1825 1826 if (error == 0) { 1827 /* 1828 * If the write-cache is disabled or 'sync' property 1829 * is set to 'always' then treat this as a synchronous 1830 * operation (i.e. commit to zil). 1831 */ 1832 if (!(zv->zv_flags & ZVOL_WCE) || 1833 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)) 1834 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1835 1836 /* 1837 * If the caller really wants synchronous writes, and 1838 * can't wait for them, don't return until the write 1839 * is done. 1840 */ 1841 if (df.df_flags & DF_WAIT_SYNC) { 1842 txg_wait_synced( 1843 dmu_objset_pool(zv->zv_objset), 0); 1844 } 1845 } 1846 return (error); 1847 } 1848 1849 default: 1850 error = SET_ERROR(ENOTTY); 1851 break; 1852 1853 } 1854 mutex_exit(&zfsdev_state_lock); 1855 return (error); 1856 } 1857 1858 int 1859 zvol_busy(void) 1860 { 1861 return (zvol_minors != 0); 1862 } 1863 1864 void 1865 zvol_init(void) 1866 { 1867 VERIFY(ddi_soft_state_init(&zfsdev_state, sizeof (zfs_soft_state_t), 1868 1) == 0); 1869 mutex_init(&zfsdev_state_lock, NULL, MUTEX_DEFAULT, NULL); 1870 } 1871 1872 void 1873 zvol_fini(void) 1874 { 1875 mutex_destroy(&zfsdev_state_lock); 1876 ddi_soft_state_fini(&zfsdev_state); 1877 } 1878 1879 /*ARGSUSED*/ 1880 static int 1881 zfs_mvdev_dump_feature_check(void *arg, dmu_tx_t *tx) 1882 { 1883 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 1884 1885 if (spa_feature_is_active(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP)) 1886 return (1); 1887 return (0); 1888 } 1889 1890 /*ARGSUSED*/ 1891 static void 1892 zfs_mvdev_dump_activate_feature_sync(void *arg, dmu_tx_t *tx) 1893 { 1894 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 1895 1896 spa_feature_incr(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP, tx); 1897 } 1898 1899 static int 1900 zvol_dump_init(zvol_state_t *zv, boolean_t resize) 1901 { 1902 dmu_tx_t *tx; 1903 int error; 1904 objset_t *os = zv->zv_objset; 1905 spa_t *spa = dmu_objset_spa(os); 1906 vdev_t *vd = spa->spa_root_vdev; 1907 nvlist_t *nv = NULL; 1908 uint64_t version = spa_version(spa); 1909 enum zio_checksum checksum; 1910 1911 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 1912 ASSERT(vd->vdev_ops == &vdev_root_ops); 1913 1914 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 0, 1915 DMU_OBJECT_END); 1916 /* wait for dmu_free_long_range to actually free the blocks */ 1917 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 1918 1919 /* 1920 * If the pool on which the dump device is being initialized has more 1921 * than one child vdev, check that the MULTI_VDEV_CRASH_DUMP feature is 1922 * enabled. If so, bump that feature's counter to indicate that the 1923 * feature is active. We also check the vdev type to handle the 1924 * following case: 1925 * # zpool create test raidz disk1 disk2 disk3 1926 * Now have spa_root_vdev->vdev_children == 1 (the raidz vdev), 1927 * the raidz vdev itself has 3 children. 1928 */ 1929 if (vd->vdev_children > 1 || vd->vdev_ops == &vdev_raidz_ops) { 1930 if (!spa_feature_is_enabled(spa, 1931 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP)) 1932 return (SET_ERROR(ENOTSUP)); 1933 (void) dsl_sync_task(spa_name(spa), 1934 zfs_mvdev_dump_feature_check, 1935 zfs_mvdev_dump_activate_feature_sync, NULL, 1936 2, ZFS_SPACE_CHECK_RESERVED); 1937 } 1938 1939 tx = dmu_tx_create(os); 1940 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 1941 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 1942 error = dmu_tx_assign(tx, TXG_WAIT); 1943 if (error) { 1944 dmu_tx_abort(tx); 1945 return (error); 1946 } 1947 1948 /* 1949 * If MULTI_VDEV_CRASH_DUMP is active, use the NOPARITY checksum 1950 * function. Otherwise, use the old default -- OFF. 1951 */ 1952 checksum = spa_feature_is_active(spa, 1953 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP) ? ZIO_CHECKSUM_NOPARITY : 1954 ZIO_CHECKSUM_OFF; 1955 1956 /* 1957 * If we are resizing the dump device then we only need to 1958 * update the refreservation to match the newly updated 1959 * zvolsize. Otherwise, we save off the original state of the 1960 * zvol so that we can restore them if the zvol is ever undumpified. 1961 */ 1962 if (resize) { 1963 error = zap_update(os, ZVOL_ZAP_OBJ, 1964 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 1965 &zv->zv_volsize, tx); 1966 } else { 1967 uint64_t checksum, compress, refresrv, vbs, dedup; 1968 1969 error = dsl_prop_get_integer(zv->zv_name, 1970 zfs_prop_to_name(ZFS_PROP_COMPRESSION), &compress, NULL); 1971 error = error ? error : dsl_prop_get_integer(zv->zv_name, 1972 zfs_prop_to_name(ZFS_PROP_CHECKSUM), &checksum, NULL); 1973 error = error ? error : dsl_prop_get_integer(zv->zv_name, 1974 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &refresrv, NULL); 1975 error = error ? error : dsl_prop_get_integer(zv->zv_name, 1976 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &vbs, NULL); 1977 if (version >= SPA_VERSION_DEDUP) { 1978 error = error ? error : 1979 dsl_prop_get_integer(zv->zv_name, 1980 zfs_prop_to_name(ZFS_PROP_DEDUP), &dedup, NULL); 1981 } 1982 1983 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1984 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, 1985 &compress, tx); 1986 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1987 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum, tx); 1988 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1989 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 1990 &refresrv, tx); 1991 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1992 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, 1993 &vbs, tx); 1994 error = error ? error : dmu_object_set_blocksize( 1995 os, ZVOL_OBJ, SPA_OLD_MAXBLOCKSIZE, 0, tx); 1996 if (version >= SPA_VERSION_DEDUP) { 1997 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1998 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, 1999 &dedup, tx); 2000 } 2001 if (error == 0) 2002 zv->zv_volblocksize = SPA_OLD_MAXBLOCKSIZE; 2003 } 2004 dmu_tx_commit(tx); 2005 2006 /* 2007 * We only need update the zvol's property if we are initializing 2008 * the dump area for the first time. 2009 */ 2010 if (!resize) { 2011 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 2012 VERIFY(nvlist_add_uint64(nv, 2013 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 0) == 0); 2014 VERIFY(nvlist_add_uint64(nv, 2015 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 2016 ZIO_COMPRESS_OFF) == 0); 2017 VERIFY(nvlist_add_uint64(nv, 2018 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 2019 checksum) == 0); 2020 if (version >= SPA_VERSION_DEDUP) { 2021 VERIFY(nvlist_add_uint64(nv, 2022 zfs_prop_to_name(ZFS_PROP_DEDUP), 2023 ZIO_CHECKSUM_OFF) == 0); 2024 } 2025 2026 error = zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL, 2027 nv, NULL); 2028 nvlist_free(nv); 2029 2030 if (error) 2031 return (error); 2032 } 2033 2034 /* Allocate the space for the dump */ 2035 error = zvol_prealloc(zv); 2036 return (error); 2037 } 2038 2039 static int 2040 zvol_dumpify(zvol_state_t *zv) 2041 { 2042 int error = 0; 2043 uint64_t dumpsize = 0; 2044 dmu_tx_t *tx; 2045 objset_t *os = zv->zv_objset; 2046 2047 if (zv->zv_flags & ZVOL_RDONLY) 2048 return (SET_ERROR(EROFS)); 2049 2050 if (zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 2051 8, 1, &dumpsize) != 0 || dumpsize != zv->zv_volsize) { 2052 boolean_t resize = (dumpsize > 0); 2053 2054 if ((error = zvol_dump_init(zv, resize)) != 0) { 2055 (void) zvol_dump_fini(zv); 2056 return (error); 2057 } 2058 } 2059 2060 /* 2061 * Build up our lba mapping. 2062 */ 2063 error = zvol_get_lbas(zv); 2064 if (error) { 2065 (void) zvol_dump_fini(zv); 2066 return (error); 2067 } 2068 2069 tx = dmu_tx_create(os); 2070 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 2071 error = dmu_tx_assign(tx, TXG_WAIT); 2072 if (error) { 2073 dmu_tx_abort(tx); 2074 (void) zvol_dump_fini(zv); 2075 return (error); 2076 } 2077 2078 zv->zv_flags |= ZVOL_DUMPIFIED; 2079 error = zap_update(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 8, 1, 2080 &zv->zv_volsize, tx); 2081 dmu_tx_commit(tx); 2082 2083 if (error) { 2084 (void) zvol_dump_fini(zv); 2085 return (error); 2086 } 2087 2088 txg_wait_synced(dmu_objset_pool(os), 0); 2089 return (0); 2090 } 2091 2092 static int 2093 zvol_dump_fini(zvol_state_t *zv) 2094 { 2095 dmu_tx_t *tx; 2096 objset_t *os = zv->zv_objset; 2097 nvlist_t *nv; 2098 int error = 0; 2099 uint64_t checksum, compress, refresrv, vbs, dedup; 2100 uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset)); 2101 2102 /* 2103 * Attempt to restore the zvol back to its pre-dumpified state. 2104 * This is a best-effort attempt as it's possible that not all 2105 * of these properties were initialized during the dumpify process 2106 * (i.e. error during zvol_dump_init). 2107 */ 2108 2109 tx = dmu_tx_create(os); 2110 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 2111 error = dmu_tx_assign(tx, TXG_WAIT); 2112 if (error) { 2113 dmu_tx_abort(tx); 2114 return (error); 2115 } 2116 (void) zap_remove(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, tx); 2117 dmu_tx_commit(tx); 2118 2119 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2120 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum); 2121 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2122 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, &compress); 2123 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2124 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, &refresrv); 2125 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2126 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, &vbs); 2127 2128 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 2129 (void) nvlist_add_uint64(nv, 2130 zfs_prop_to_name(ZFS_PROP_CHECKSUM), checksum); 2131 (void) nvlist_add_uint64(nv, 2132 zfs_prop_to_name(ZFS_PROP_COMPRESSION), compress); 2133 (void) nvlist_add_uint64(nv, 2134 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), refresrv); 2135 if (version >= SPA_VERSION_DEDUP && 2136 zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2137 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, &dedup) == 0) { 2138 (void) nvlist_add_uint64(nv, 2139 zfs_prop_to_name(ZFS_PROP_DEDUP), dedup); 2140 } 2141 (void) zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL, 2142 nv, NULL); 2143 nvlist_free(nv); 2144 2145 zvol_free_extents(zv); 2146 zv->zv_flags &= ~ZVOL_DUMPIFIED; 2147 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, DMU_OBJECT_END); 2148 /* wait for dmu_free_long_range to actually free the blocks */ 2149 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 2150 tx = dmu_tx_create(os); 2151 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 2152 error = dmu_tx_assign(tx, TXG_WAIT); 2153 if (error) { 2154 dmu_tx_abort(tx); 2155 return (error); 2156 } 2157 if (dmu_object_set_blocksize(os, ZVOL_OBJ, vbs, 0, tx) == 0) 2158 zv->zv_volblocksize = vbs; 2159 dmu_tx_commit(tx); 2160 2161 return (0); 2162 } 2163