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