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, 2017 by Delphix. All rights reserved. 28 * Copyright (c) 2013, Joyent, Inc. All rights reserved. 29 * Copyright (c) 2014 Integros [integros.com] 30 */ 31 32 /* 33 * ZFS volume emulation driver. 34 * 35 * Makes a DMU object look like a volume of arbitrary size, up to 2^64 bytes. 36 * Volumes are accessed through the symbolic links named: 37 * 38 * /dev/zvol/dsk/<pool_name>/<dataset_name> 39 * /dev/zvol/rdsk/<pool_name>/<dataset_name> 40 * 41 * These links are created by the /dev filesystem (sdev_zvolops.c). 42 * Volumes are persistent through reboot. No user command needs to be 43 * run before opening and using a device. 44 */ 45 46 #include <sys/types.h> 47 #include <sys/param.h> 48 #include <sys/errno.h> 49 #include <sys/uio.h> 50 #include <sys/buf.h> 51 #include <sys/modctl.h> 52 #include <sys/open.h> 53 #include <sys/kmem.h> 54 #include <sys/conf.h> 55 #include <sys/cmn_err.h> 56 #include <sys/stat.h> 57 #include <sys/zap.h> 58 #include <sys/spa.h> 59 #include <sys/spa_impl.h> 60 #include <sys/zio.h> 61 #include <sys/dmu_traverse.h> 62 #include <sys/dnode.h> 63 #include <sys/dsl_dataset.h> 64 #include <sys/dsl_prop.h> 65 #include <sys/dkio.h> 66 #include <sys/efi_partition.h> 67 #include <sys/byteorder.h> 68 #include <sys/pathname.h> 69 #include <sys/ddi.h> 70 #include <sys/sunddi.h> 71 #include <sys/crc32.h> 72 #include <sys/dirent.h> 73 #include <sys/policy.h> 74 #include <sys/fs/zfs.h> 75 #include <sys/zfs_ioctl.h> 76 #include <sys/mkdev.h> 77 #include <sys/zil.h> 78 #include <sys/refcount.h> 79 #include <sys/zfs_znode.h> 80 #include <sys/zfs_rlock.h> 81 #include <sys/vdev_disk.h> 82 #include <sys/vdev_impl.h> 83 #include <sys/vdev_raidz.h> 84 #include <sys/zvol.h> 85 #include <sys/dumphdr.h> 86 #include <sys/zil_impl.h> 87 #include <sys/dbuf.h> 88 #include <sys/dmu_tx.h> 89 #include <sys/zfeature.h> 90 #include <sys/zio_checksum.h> 91 #include <sys/zil_impl.h> 92 93 #include "zfs_namecheck.h" 94 95 void *zfsdev_state; 96 static char *zvol_tag = "zvol_tag"; 97 98 #define ZVOL_DUMPSIZE "dumpsize" 99 100 /* 101 * This lock protects the zfsdev_state structure from being modified 102 * while it's being used, e.g. an open that comes in before a create 103 * finishes. It also protects temporary opens of the dataset so that, 104 * e.g., an open doesn't get a spurious EBUSY. 105 */ 106 kmutex_t zfsdev_state_lock; 107 static uint32_t zvol_minors; 108 109 typedef struct zvol_extent { 110 list_node_t ze_node; 111 dva_t ze_dva; /* dva associated with this extent */ 112 uint64_t ze_nblks; /* number of blocks in extent */ 113 } zvol_extent_t; 114 115 /* 116 * The in-core state of each volume. 117 */ 118 typedef struct zvol_state { 119 char zv_name[MAXPATHLEN]; /* pool/dd name */ 120 uint64_t zv_volsize; /* amount of space we advertise */ 121 uint64_t zv_volblocksize; /* volume block size */ 122 minor_t zv_minor; /* minor number */ 123 uint8_t zv_min_bs; /* minimum addressable block shift */ 124 uint8_t zv_flags; /* readonly, dumpified, etc. */ 125 objset_t *zv_objset; /* objset handle */ 126 uint32_t zv_open_count[OTYPCNT]; /* open counts */ 127 uint32_t zv_total_opens; /* total open count */ 128 zilog_t *zv_zilog; /* ZIL handle */ 129 list_t zv_extents; /* List of extents for dump */ 130 znode_t zv_znode; /* for range locking */ 131 dmu_buf_t *zv_dbuf; /* bonus handle */ 132 } zvol_state_t; 133 134 /* 135 * zvol specific flags 136 */ 137 #define ZVOL_RDONLY 0x1 138 #define ZVOL_DUMPIFIED 0x2 139 #define ZVOL_EXCL 0x4 140 #define ZVOL_WCE 0x8 141 142 /* 143 * zvol maximum transfer in one DMU tx. 144 */ 145 int zvol_maxphys = DMU_MAX_ACCESS/2; 146 147 /* 148 * Toggle unmap functionality. 149 */ 150 boolean_t zvol_unmap_enabled = B_TRUE; 151 152 /* 153 * If true, unmaps requested as synchronous are executed synchronously, 154 * otherwise all unmaps are asynchronous. 155 */ 156 boolean_t zvol_unmap_sync_enabled = B_FALSE; 157 158 extern int zfs_set_prop_nvlist(const char *, zprop_source_t, 159 nvlist_t *, nvlist_t *); 160 static int zvol_remove_zv(zvol_state_t *); 161 static int zvol_get_data(void *arg, lr_write_t *lr, char *buf, 162 struct lwb *lwb, zio_t *zio); 163 static int zvol_dumpify(zvol_state_t *zv); 164 static int zvol_dump_fini(zvol_state_t *zv); 165 static int zvol_dump_init(zvol_state_t *zv, boolean_t resize); 166 167 static void 168 zvol_size_changed(zvol_state_t *zv, uint64_t volsize) 169 { 170 dev_t dev = makedevice(ddi_driver_major(zfs_dip), zv->zv_minor); 171 172 zv->zv_volsize = volsize; 173 VERIFY(ddi_prop_update_int64(dev, zfs_dip, 174 "Size", volsize) == DDI_SUCCESS); 175 VERIFY(ddi_prop_update_int64(dev, zfs_dip, 176 "Nblocks", lbtodb(volsize)) == DDI_SUCCESS); 177 178 /* Notify specfs to invalidate the cached size */ 179 spec_size_invalidate(dev, VBLK); 180 spec_size_invalidate(dev, VCHR); 181 } 182 183 int 184 zvol_check_volsize(uint64_t volsize, uint64_t blocksize) 185 { 186 if (volsize == 0) 187 return (SET_ERROR(EINVAL)); 188 189 if (volsize % blocksize != 0) 190 return (SET_ERROR(EINVAL)); 191 192 #ifdef _ILP32 193 if (volsize - 1 > SPEC_MAXOFFSET_T) 194 return (SET_ERROR(EOVERFLOW)); 195 #endif 196 return (0); 197 } 198 199 int 200 zvol_check_volblocksize(uint64_t volblocksize) 201 { 202 if (volblocksize < SPA_MINBLOCKSIZE || 203 volblocksize > SPA_OLD_MAXBLOCKSIZE || 204 !ISP2(volblocksize)) 205 return (SET_ERROR(EDOM)); 206 207 return (0); 208 } 209 210 int 211 zvol_get_stats(objset_t *os, nvlist_t *nv) 212 { 213 int error; 214 dmu_object_info_t doi; 215 uint64_t val; 216 217 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val); 218 if (error) 219 return (error); 220 221 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val); 222 223 error = dmu_object_info(os, ZVOL_OBJ, &doi); 224 225 if (error == 0) { 226 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE, 227 doi.doi_data_block_size); 228 } 229 230 return (error); 231 } 232 233 static zvol_state_t * 234 zvol_minor_lookup(const char *name) 235 { 236 minor_t minor; 237 zvol_state_t *zv; 238 239 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 240 241 for (minor = 1; minor <= ZFSDEV_MAX_MINOR; minor++) { 242 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 243 if (zv == NULL) 244 continue; 245 if (strcmp(zv->zv_name, name) == 0) 246 return (zv); 247 } 248 249 return (NULL); 250 } 251 252 /* extent mapping arg */ 253 struct maparg { 254 zvol_state_t *ma_zv; 255 uint64_t ma_blks; 256 }; 257 258 /*ARGSUSED*/ 259 static int 260 zvol_map_block(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, 261 const zbookmark_phys_t *zb, const dnode_phys_t *dnp, void *arg) 262 { 263 struct maparg *ma = arg; 264 zvol_extent_t *ze; 265 int bs = ma->ma_zv->zv_volblocksize; 266 267 if (bp == NULL || BP_IS_HOLE(bp) || 268 zb->zb_object != ZVOL_OBJ || zb->zb_level != 0) 269 return (0); 270 271 VERIFY(!BP_IS_EMBEDDED(bp)); 272 273 VERIFY3U(ma->ma_blks, ==, zb->zb_blkid); 274 ma->ma_blks++; 275 276 /* Abort immediately if we have encountered gang blocks */ 277 if (BP_IS_GANG(bp)) 278 return (SET_ERROR(EFRAGS)); 279 280 /* 281 * See if the block is at the end of the previous extent. 282 */ 283 ze = list_tail(&ma->ma_zv->zv_extents); 284 if (ze && 285 DVA_GET_VDEV(BP_IDENTITY(bp)) == DVA_GET_VDEV(&ze->ze_dva) && 286 DVA_GET_OFFSET(BP_IDENTITY(bp)) == 287 DVA_GET_OFFSET(&ze->ze_dva) + ze->ze_nblks * bs) { 288 ze->ze_nblks++; 289 return (0); 290 } 291 292 dprintf_bp(bp, "%s", "next blkptr:"); 293 294 /* start a new extent */ 295 ze = kmem_zalloc(sizeof (zvol_extent_t), KM_SLEEP); 296 ze->ze_dva = bp->blk_dva[0]; /* structure assignment */ 297 ze->ze_nblks = 1; 298 list_insert_tail(&ma->ma_zv->zv_extents, ze); 299 return (0); 300 } 301 302 static void 303 zvol_free_extents(zvol_state_t *zv) 304 { 305 zvol_extent_t *ze; 306 307 while (ze = list_head(&zv->zv_extents)) { 308 list_remove(&zv->zv_extents, ze); 309 kmem_free(ze, sizeof (zvol_extent_t)); 310 } 311 } 312 313 static int 314 zvol_get_lbas(zvol_state_t *zv) 315 { 316 objset_t *os = zv->zv_objset; 317 struct maparg ma; 318 int err; 319 320 ma.ma_zv = zv; 321 ma.ma_blks = 0; 322 zvol_free_extents(zv); 323 324 /* commit any in-flight changes before traversing the dataset */ 325 txg_wait_synced(dmu_objset_pool(os), 0); 326 err = traverse_dataset(dmu_objset_ds(os), 0, 327 TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA, zvol_map_block, &ma); 328 if (err || ma.ma_blks != (zv->zv_volsize / zv->zv_volblocksize)) { 329 zvol_free_extents(zv); 330 return (err ? err : EIO); 331 } 332 333 return (0); 334 } 335 336 /* ARGSUSED */ 337 void 338 zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx) 339 { 340 zfs_creat_t *zct = arg; 341 nvlist_t *nvprops = zct->zct_props; 342 int error; 343 uint64_t volblocksize, volsize; 344 345 VERIFY(nvlist_lookup_uint64(nvprops, 346 zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0); 347 if (nvlist_lookup_uint64(nvprops, 348 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0) 349 volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE); 350 351 /* 352 * These properties must be removed from the list so the generic 353 * property setting step won't apply to them. 354 */ 355 VERIFY(nvlist_remove_all(nvprops, 356 zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0); 357 (void) nvlist_remove_all(nvprops, 358 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE)); 359 360 error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize, 361 DMU_OT_NONE, 0, tx); 362 ASSERT(error == 0); 363 364 error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP, 365 DMU_OT_NONE, 0, tx); 366 ASSERT(error == 0); 367 368 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx); 369 ASSERT(error == 0); 370 } 371 372 /* 373 * Replay a TX_TRUNCATE ZIL transaction if asked. TX_TRUNCATE is how we 374 * implement DKIOCFREE/free-long-range. 375 */ 376 static int 377 zvol_replay_truncate(zvol_state_t *zv, lr_truncate_t *lr, boolean_t byteswap) 378 { 379 uint64_t offset, length; 380 381 if (byteswap) 382 byteswap_uint64_array(lr, sizeof (*lr)); 383 384 offset = lr->lr_offset; 385 length = lr->lr_length; 386 387 return (dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, offset, length)); 388 } 389 390 /* 391 * Replay a TX_WRITE ZIL transaction that didn't get committed 392 * after a system failure 393 */ 394 static int 395 zvol_replay_write(zvol_state_t *zv, lr_write_t *lr, boolean_t byteswap) 396 { 397 objset_t *os = zv->zv_objset; 398 char *data = (char *)(lr + 1); /* data follows lr_write_t */ 399 uint64_t offset, length; 400 dmu_tx_t *tx; 401 int error; 402 403 if (byteswap) 404 byteswap_uint64_array(lr, sizeof (*lr)); 405 406 offset = lr->lr_offset; 407 length = lr->lr_length; 408 409 /* If it's a dmu_sync() block, write the whole block */ 410 if (lr->lr_common.lrc_reclen == sizeof (lr_write_t)) { 411 uint64_t blocksize = BP_GET_LSIZE(&lr->lr_blkptr); 412 if (length < blocksize) { 413 offset -= offset % blocksize; 414 length = blocksize; 415 } 416 } 417 418 tx = dmu_tx_create(os); 419 dmu_tx_hold_write(tx, ZVOL_OBJ, offset, length); 420 error = dmu_tx_assign(tx, TXG_WAIT); 421 if (error) { 422 dmu_tx_abort(tx); 423 } else { 424 dmu_write(os, ZVOL_OBJ, offset, length, data, tx); 425 dmu_tx_commit(tx); 426 } 427 428 return (error); 429 } 430 431 /* ARGSUSED */ 432 static int 433 zvol_replay_err(zvol_state_t *zv, lr_t *lr, boolean_t byteswap) 434 { 435 return (SET_ERROR(ENOTSUP)); 436 } 437 438 /* 439 * Callback vectors for replaying records. 440 * Only TX_WRITE and TX_TRUNCATE are needed for zvol. 441 */ 442 zil_replay_func_t *zvol_replay_vector[TX_MAX_TYPE] = { 443 zvol_replay_err, /* 0 no such transaction type */ 444 zvol_replay_err, /* TX_CREATE */ 445 zvol_replay_err, /* TX_MKDIR */ 446 zvol_replay_err, /* TX_MKXATTR */ 447 zvol_replay_err, /* TX_SYMLINK */ 448 zvol_replay_err, /* TX_REMOVE */ 449 zvol_replay_err, /* TX_RMDIR */ 450 zvol_replay_err, /* TX_LINK */ 451 zvol_replay_err, /* TX_RENAME */ 452 zvol_replay_write, /* TX_WRITE */ 453 zvol_replay_truncate, /* TX_TRUNCATE */ 454 zvol_replay_err, /* TX_SETATTR */ 455 zvol_replay_err, /* TX_ACL */ 456 zvol_replay_err, /* TX_CREATE_ACL */ 457 zvol_replay_err, /* TX_CREATE_ATTR */ 458 zvol_replay_err, /* TX_CREATE_ACL_ATTR */ 459 zvol_replay_err, /* TX_MKDIR_ACL */ 460 zvol_replay_err, /* TX_MKDIR_ATTR */ 461 zvol_replay_err, /* TX_MKDIR_ACL_ATTR */ 462 zvol_replay_err, /* TX_WRITE2 */ 463 }; 464 465 int 466 zvol_name2minor(const char *name, minor_t *minor) 467 { 468 zvol_state_t *zv; 469 470 mutex_enter(&zfsdev_state_lock); 471 zv = zvol_minor_lookup(name); 472 if (minor && zv) 473 *minor = zv->zv_minor; 474 mutex_exit(&zfsdev_state_lock); 475 return (zv ? 0 : -1); 476 } 477 478 /* 479 * Create a minor node (plus a whole lot more) for the specified volume. 480 */ 481 int 482 zvol_create_minor(const char *name) 483 { 484 zfs_soft_state_t *zs; 485 zvol_state_t *zv; 486 objset_t *os; 487 dmu_object_info_t doi; 488 minor_t minor = 0; 489 char chrbuf[30], blkbuf[30]; 490 int error; 491 492 mutex_enter(&zfsdev_state_lock); 493 494 if (zvol_minor_lookup(name) != NULL) { 495 mutex_exit(&zfsdev_state_lock); 496 return (SET_ERROR(EEXIST)); 497 } 498 499 /* lie and say we're read-only */ 500 error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, FTAG, &os); 501 502 if (error) { 503 mutex_exit(&zfsdev_state_lock); 504 return (error); 505 } 506 507 if ((minor = zfsdev_minor_alloc()) == 0) { 508 dmu_objset_disown(os, FTAG); 509 mutex_exit(&zfsdev_state_lock); 510 return (SET_ERROR(ENXIO)); 511 } 512 513 if (ddi_soft_state_zalloc(zfsdev_state, minor) != DDI_SUCCESS) { 514 dmu_objset_disown(os, FTAG); 515 mutex_exit(&zfsdev_state_lock); 516 return (SET_ERROR(EAGAIN)); 517 } 518 (void) ddi_prop_update_string(minor, zfs_dip, ZVOL_PROP_NAME, 519 (char *)name); 520 521 (void) snprintf(chrbuf, sizeof (chrbuf), "%u,raw", minor); 522 523 if (ddi_create_minor_node(zfs_dip, chrbuf, S_IFCHR, 524 minor, DDI_PSEUDO, 0) == DDI_FAILURE) { 525 ddi_soft_state_free(zfsdev_state, minor); 526 dmu_objset_disown(os, FTAG); 527 mutex_exit(&zfsdev_state_lock); 528 return (SET_ERROR(EAGAIN)); 529 } 530 531 (void) snprintf(blkbuf, sizeof (blkbuf), "%u", minor); 532 533 if (ddi_create_minor_node(zfs_dip, blkbuf, S_IFBLK, 534 minor, DDI_PSEUDO, 0) == DDI_FAILURE) { 535 ddi_remove_minor_node(zfs_dip, chrbuf); 536 ddi_soft_state_free(zfsdev_state, minor); 537 dmu_objset_disown(os, FTAG); 538 mutex_exit(&zfsdev_state_lock); 539 return (SET_ERROR(EAGAIN)); 540 } 541 542 zs = ddi_get_soft_state(zfsdev_state, minor); 543 zs->zss_type = ZSST_ZVOL; 544 zv = zs->zss_data = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP); 545 (void) strlcpy(zv->zv_name, name, MAXPATHLEN); 546 zv->zv_min_bs = DEV_BSHIFT; 547 zv->zv_minor = minor; 548 zv->zv_objset = os; 549 if (dmu_objset_is_snapshot(os) || !spa_writeable(dmu_objset_spa(os))) 550 zv->zv_flags |= ZVOL_RDONLY; 551 mutex_init(&zv->zv_znode.z_range_lock, NULL, MUTEX_DEFAULT, NULL); 552 avl_create(&zv->zv_znode.z_range_avl, zfs_range_compare, 553 sizeof (rl_t), offsetof(rl_t, r_node)); 554 list_create(&zv->zv_extents, sizeof (zvol_extent_t), 555 offsetof(zvol_extent_t, ze_node)); 556 /* get and cache the blocksize */ 557 error = dmu_object_info(os, ZVOL_OBJ, &doi); 558 ASSERT(error == 0); 559 zv->zv_volblocksize = doi.doi_data_block_size; 560 561 if (spa_writeable(dmu_objset_spa(os))) { 562 if (zil_replay_disable) 563 zil_destroy(dmu_objset_zil(os), B_FALSE); 564 else 565 zil_replay(os, zv, zvol_replay_vector); 566 } 567 dmu_objset_disown(os, FTAG); 568 zv->zv_objset = NULL; 569 570 zvol_minors++; 571 572 mutex_exit(&zfsdev_state_lock); 573 574 return (0); 575 } 576 577 /* 578 * Remove minor node for the specified volume. 579 */ 580 static int 581 zvol_remove_zv(zvol_state_t *zv) 582 { 583 char nmbuf[20]; 584 minor_t minor = zv->zv_minor; 585 586 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 587 if (zv->zv_total_opens != 0) 588 return (SET_ERROR(EBUSY)); 589 590 (void) snprintf(nmbuf, sizeof (nmbuf), "%u,raw", minor); 591 ddi_remove_minor_node(zfs_dip, nmbuf); 592 593 (void) snprintf(nmbuf, sizeof (nmbuf), "%u", minor); 594 ddi_remove_minor_node(zfs_dip, nmbuf); 595 596 avl_destroy(&zv->zv_znode.z_range_avl); 597 mutex_destroy(&zv->zv_znode.z_range_lock); 598 599 kmem_free(zv, sizeof (zvol_state_t)); 600 601 ddi_soft_state_free(zfsdev_state, minor); 602 603 zvol_minors--; 604 return (0); 605 } 606 607 int 608 zvol_remove_minor(const char *name) 609 { 610 zvol_state_t *zv; 611 int rc; 612 613 mutex_enter(&zfsdev_state_lock); 614 if ((zv = zvol_minor_lookup(name)) == NULL) { 615 mutex_exit(&zfsdev_state_lock); 616 return (SET_ERROR(ENXIO)); 617 } 618 rc = zvol_remove_zv(zv); 619 mutex_exit(&zfsdev_state_lock); 620 return (rc); 621 } 622 623 int 624 zvol_first_open(zvol_state_t *zv) 625 { 626 objset_t *os; 627 uint64_t volsize; 628 int error; 629 uint64_t readonly; 630 631 /* lie and say we're read-only */ 632 error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, B_TRUE, 633 zvol_tag, &os); 634 if (error) 635 return (error); 636 637 zv->zv_objset = os; 638 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize); 639 if (error) { 640 ASSERT(error == 0); 641 dmu_objset_disown(os, zvol_tag); 642 return (error); 643 } 644 645 error = dmu_bonus_hold(os, ZVOL_OBJ, zvol_tag, &zv->zv_dbuf); 646 if (error) { 647 dmu_objset_disown(os, zvol_tag); 648 return (error); 649 } 650 651 zvol_size_changed(zv, volsize); 652 zv->zv_zilog = zil_open(os, zvol_get_data); 653 654 VERIFY(dsl_prop_get_integer(zv->zv_name, "readonly", &readonly, 655 NULL) == 0); 656 if (readonly || dmu_objset_is_snapshot(os) || 657 !spa_writeable(dmu_objset_spa(os))) 658 zv->zv_flags |= ZVOL_RDONLY; 659 else 660 zv->zv_flags &= ~ZVOL_RDONLY; 661 return (error); 662 } 663 664 void 665 zvol_last_close(zvol_state_t *zv) 666 { 667 zil_close(zv->zv_zilog); 668 zv->zv_zilog = NULL; 669 670 dmu_buf_rele(zv->zv_dbuf, zvol_tag); 671 zv->zv_dbuf = NULL; 672 673 /* 674 * Evict cached data 675 */ 676 if (dsl_dataset_is_dirty(dmu_objset_ds(zv->zv_objset)) && 677 !(zv->zv_flags & ZVOL_RDONLY)) 678 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 679 dmu_objset_evict_dbufs(zv->zv_objset); 680 681 dmu_objset_disown(zv->zv_objset, zvol_tag); 682 zv->zv_objset = NULL; 683 } 684 685 int 686 zvol_prealloc(zvol_state_t *zv) 687 { 688 objset_t *os = zv->zv_objset; 689 dmu_tx_t *tx; 690 uint64_t refd, avail, usedobjs, availobjs; 691 uint64_t resid = zv->zv_volsize; 692 uint64_t off = 0; 693 694 /* Check the space usage before attempting to allocate the space */ 695 dmu_objset_space(os, &refd, &avail, &usedobjs, &availobjs); 696 if (avail < zv->zv_volsize) 697 return (SET_ERROR(ENOSPC)); 698 699 /* Free old extents if they exist */ 700 zvol_free_extents(zv); 701 702 while (resid != 0) { 703 int error; 704 uint64_t bytes = MIN(resid, SPA_OLD_MAXBLOCKSIZE); 705 706 tx = dmu_tx_create(os); 707 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes); 708 error = dmu_tx_assign(tx, TXG_WAIT); 709 if (error) { 710 dmu_tx_abort(tx); 711 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, off); 712 return (error); 713 } 714 dmu_prealloc(os, ZVOL_OBJ, off, bytes, tx); 715 dmu_tx_commit(tx); 716 off += bytes; 717 resid -= bytes; 718 } 719 txg_wait_synced(dmu_objset_pool(os), 0); 720 721 return (0); 722 } 723 724 static int 725 zvol_update_volsize(objset_t *os, uint64_t volsize) 726 { 727 dmu_tx_t *tx; 728 int error; 729 730 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 731 732 tx = dmu_tx_create(os); 733 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 734 dmu_tx_mark_netfree(tx); 735 error = dmu_tx_assign(tx, TXG_WAIT); 736 if (error) { 737 dmu_tx_abort(tx); 738 return (error); 739 } 740 741 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, 742 &volsize, tx); 743 dmu_tx_commit(tx); 744 745 if (error == 0) 746 error = dmu_free_long_range(os, 747 ZVOL_OBJ, volsize, DMU_OBJECT_END); 748 return (error); 749 } 750 751 void 752 zvol_remove_minors(const char *name) 753 { 754 zvol_state_t *zv; 755 char *namebuf; 756 minor_t minor; 757 758 namebuf = kmem_zalloc(strlen(name) + 2, KM_SLEEP); 759 (void) strncpy(namebuf, name, strlen(name)); 760 (void) strcat(namebuf, "/"); 761 mutex_enter(&zfsdev_state_lock); 762 for (minor = 1; minor <= ZFSDEV_MAX_MINOR; minor++) { 763 764 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 765 if (zv == NULL) 766 continue; 767 if (strncmp(namebuf, zv->zv_name, strlen(namebuf)) == 0) 768 (void) zvol_remove_zv(zv); 769 } 770 kmem_free(namebuf, strlen(name) + 2); 771 772 mutex_exit(&zfsdev_state_lock); 773 } 774 775 static int 776 zvol_update_live_volsize(zvol_state_t *zv, uint64_t volsize) 777 { 778 uint64_t old_volsize = 0ULL; 779 int error = 0; 780 781 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 782 783 /* 784 * Reinitialize the dump area to the new size. If we 785 * failed to resize the dump area then restore it back to 786 * its original size. We must set the new volsize prior 787 * to calling dumpvp_resize() to ensure that the devices' 788 * size(9P) is not visible by the dump subsystem. 789 */ 790 old_volsize = zv->zv_volsize; 791 zvol_size_changed(zv, volsize); 792 793 if (zv->zv_flags & ZVOL_DUMPIFIED) { 794 if ((error = zvol_dumpify(zv)) != 0 || 795 (error = dumpvp_resize()) != 0) { 796 int dumpify_error; 797 798 (void) zvol_update_volsize(zv->zv_objset, old_volsize); 799 zvol_size_changed(zv, old_volsize); 800 dumpify_error = zvol_dumpify(zv); 801 error = dumpify_error ? dumpify_error : error; 802 } 803 } 804 805 /* 806 * Generate a LUN expansion event. 807 */ 808 if (error == 0) { 809 sysevent_id_t eid; 810 nvlist_t *attr; 811 char *physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 812 813 (void) snprintf(physpath, MAXPATHLEN, "%s%u", ZVOL_PSEUDO_DEV, 814 zv->zv_minor); 815 816 VERIFY(nvlist_alloc(&attr, NV_UNIQUE_NAME, KM_SLEEP) == 0); 817 VERIFY(nvlist_add_string(attr, DEV_PHYS_PATH, physpath) == 0); 818 819 (void) ddi_log_sysevent(zfs_dip, SUNW_VENDOR, EC_DEV_STATUS, 820 ESC_DEV_DLE, attr, &eid, DDI_SLEEP); 821 822 nvlist_free(attr); 823 kmem_free(physpath, MAXPATHLEN); 824 } 825 return (error); 826 } 827 828 int 829 zvol_set_volsize(const char *name, uint64_t volsize) 830 { 831 zvol_state_t *zv = NULL; 832 objset_t *os; 833 int error; 834 dmu_object_info_t doi; 835 uint64_t readonly; 836 boolean_t owned = B_FALSE; 837 838 error = dsl_prop_get_integer(name, 839 zfs_prop_to_name(ZFS_PROP_READONLY), &readonly, NULL); 840 if (error != 0) 841 return (error); 842 if (readonly) 843 return (SET_ERROR(EROFS)); 844 845 mutex_enter(&zfsdev_state_lock); 846 zv = zvol_minor_lookup(name); 847 848 if (zv == NULL || zv->zv_objset == NULL) { 849 if ((error = dmu_objset_own(name, DMU_OST_ZVOL, B_FALSE, 850 FTAG, &os)) != 0) { 851 mutex_exit(&zfsdev_state_lock); 852 return (error); 853 } 854 owned = B_TRUE; 855 if (zv != NULL) 856 zv->zv_objset = os; 857 } else { 858 os = zv->zv_objset; 859 } 860 861 if ((error = dmu_object_info(os, ZVOL_OBJ, &doi)) != 0 || 862 (error = zvol_check_volsize(volsize, doi.doi_data_block_size)) != 0) 863 goto out; 864 865 error = zvol_update_volsize(os, volsize); 866 867 if (error == 0 && zv != NULL) 868 error = zvol_update_live_volsize(zv, volsize); 869 out: 870 if (owned) { 871 dmu_objset_disown(os, FTAG); 872 if (zv != NULL) 873 zv->zv_objset = NULL; 874 } 875 mutex_exit(&zfsdev_state_lock); 876 return (error); 877 } 878 879 /*ARGSUSED*/ 880 int 881 zvol_open(dev_t *devp, int flag, int otyp, cred_t *cr) 882 { 883 zvol_state_t *zv; 884 int err = 0; 885 886 mutex_enter(&zfsdev_state_lock); 887 888 zv = zfsdev_get_soft_state(getminor(*devp), ZSST_ZVOL); 889 if (zv == NULL) { 890 mutex_exit(&zfsdev_state_lock); 891 return (SET_ERROR(ENXIO)); 892 } 893 894 if (zv->zv_total_opens == 0) 895 err = zvol_first_open(zv); 896 if (err) { 897 mutex_exit(&zfsdev_state_lock); 898 return (err); 899 } 900 if ((flag & FWRITE) && (zv->zv_flags & ZVOL_RDONLY)) { 901 err = SET_ERROR(EROFS); 902 goto out; 903 } 904 if (zv->zv_flags & ZVOL_EXCL) { 905 err = SET_ERROR(EBUSY); 906 goto out; 907 } 908 if (flag & FEXCL) { 909 if (zv->zv_total_opens != 0) { 910 err = SET_ERROR(EBUSY); 911 goto out; 912 } 913 zv->zv_flags |= ZVOL_EXCL; 914 } 915 916 if (zv->zv_open_count[otyp] == 0 || otyp == OTYP_LYR) { 917 zv->zv_open_count[otyp]++; 918 zv->zv_total_opens++; 919 } 920 mutex_exit(&zfsdev_state_lock); 921 922 return (err); 923 out: 924 if (zv->zv_total_opens == 0) 925 zvol_last_close(zv); 926 mutex_exit(&zfsdev_state_lock); 927 return (err); 928 } 929 930 /*ARGSUSED*/ 931 int 932 zvol_close(dev_t dev, int flag, int otyp, cred_t *cr) 933 { 934 minor_t minor = getminor(dev); 935 zvol_state_t *zv; 936 int error = 0; 937 938 mutex_enter(&zfsdev_state_lock); 939 940 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 941 if (zv == NULL) { 942 mutex_exit(&zfsdev_state_lock); 943 return (SET_ERROR(ENXIO)); 944 } 945 946 if (zv->zv_flags & ZVOL_EXCL) { 947 ASSERT(zv->zv_total_opens == 1); 948 zv->zv_flags &= ~ZVOL_EXCL; 949 } 950 951 /* 952 * If the open count is zero, this is a spurious close. 953 * That indicates a bug in the kernel / DDI framework. 954 */ 955 ASSERT(zv->zv_open_count[otyp] != 0); 956 ASSERT(zv->zv_total_opens != 0); 957 958 /* 959 * You may get multiple opens, but only one close. 960 */ 961 zv->zv_open_count[otyp]--; 962 zv->zv_total_opens--; 963 964 if (zv->zv_total_opens == 0) 965 zvol_last_close(zv); 966 967 mutex_exit(&zfsdev_state_lock); 968 return (error); 969 } 970 971 static void 972 zvol_get_done(zgd_t *zgd, int error) 973 { 974 if (zgd->zgd_db) 975 dmu_buf_rele(zgd->zgd_db, zgd); 976 977 zfs_range_unlock(zgd->zgd_rl); 978 979 if (error == 0 && zgd->zgd_bp) 980 zil_lwb_add_block(zgd->zgd_lwb, zgd->zgd_bp); 981 982 kmem_free(zgd, sizeof (zgd_t)); 983 } 984 985 /* 986 * Get data to generate a TX_WRITE intent log record. 987 */ 988 static int 989 zvol_get_data(void *arg, lr_write_t *lr, char *buf, struct lwb *lwb, zio_t *zio) 990 { 991 zvol_state_t *zv = arg; 992 objset_t *os = zv->zv_objset; 993 uint64_t object = ZVOL_OBJ; 994 uint64_t offset = lr->lr_offset; 995 uint64_t size = lr->lr_length; /* length of user data */ 996 dmu_buf_t *db; 997 zgd_t *zgd; 998 int error; 999 1000 ASSERT3P(lwb, !=, NULL); 1001 ASSERT3P(zio, !=, NULL); 1002 ASSERT3U(size, !=, 0); 1003 1004 zgd = kmem_zalloc(sizeof (zgd_t), KM_SLEEP); 1005 zgd->zgd_lwb = lwb; 1006 zgd->zgd_rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER); 1007 1008 /* 1009 * Write records come in two flavors: immediate and indirect. 1010 * For small writes it's cheaper to store the data with the 1011 * log record (immediate); for large writes it's cheaper to 1012 * sync the data and get a pointer to it (indirect) so that 1013 * we don't have to write the data twice. 1014 */ 1015 if (buf != NULL) { /* immediate write */ 1016 error = dmu_read(os, object, offset, size, buf, 1017 DMU_READ_NO_PREFETCH); 1018 } else { 1019 size = zv->zv_volblocksize; 1020 offset = P2ALIGN(offset, size); 1021 error = dmu_buf_hold(os, object, offset, zgd, &db, 1022 DMU_READ_NO_PREFETCH); 1023 if (error == 0) { 1024 blkptr_t *bp = &lr->lr_blkptr; 1025 1026 zgd->zgd_db = db; 1027 zgd->zgd_bp = bp; 1028 1029 ASSERT(db->db_offset == offset); 1030 ASSERT(db->db_size == size); 1031 1032 error = dmu_sync(zio, lr->lr_common.lrc_txg, 1033 zvol_get_done, zgd); 1034 1035 if (error == 0) 1036 return (0); 1037 } 1038 } 1039 1040 zvol_get_done(zgd, error); 1041 1042 return (error); 1043 } 1044 1045 /* 1046 * zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions. 1047 * 1048 * We store data in the log buffers if it's small enough. 1049 * Otherwise we will later flush the data out via dmu_sync(). 1050 */ 1051 ssize_t zvol_immediate_write_sz = 32768; 1052 1053 static void 1054 zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, offset_t off, ssize_t resid, 1055 boolean_t sync) 1056 { 1057 uint32_t blocksize = zv->zv_volblocksize; 1058 zilog_t *zilog = zv->zv_zilog; 1059 itx_wr_state_t write_state; 1060 1061 if (zil_replaying(zilog, tx)) 1062 return; 1063 1064 if (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT) 1065 write_state = WR_INDIRECT; 1066 else if (!spa_has_slogs(zilog->zl_spa) && 1067 resid >= blocksize && blocksize > zvol_immediate_write_sz) 1068 write_state = WR_INDIRECT; 1069 else if (sync) 1070 write_state = WR_COPIED; 1071 else 1072 write_state = WR_NEED_COPY; 1073 1074 while (resid) { 1075 itx_t *itx; 1076 lr_write_t *lr; 1077 itx_wr_state_t wr_state = write_state; 1078 ssize_t len = resid; 1079 1080 if (wr_state == WR_COPIED && resid > ZIL_MAX_COPIED_DATA) 1081 wr_state = WR_NEED_COPY; 1082 else if (wr_state == WR_INDIRECT) 1083 len = MIN(blocksize - P2PHASE(off, blocksize), resid); 1084 1085 itx = zil_itx_create(TX_WRITE, sizeof (*lr) + 1086 (wr_state == WR_COPIED ? len : 0)); 1087 lr = (lr_write_t *)&itx->itx_lr; 1088 if (wr_state == WR_COPIED && dmu_read(zv->zv_objset, 1089 ZVOL_OBJ, off, len, lr + 1, DMU_READ_NO_PREFETCH) != 0) { 1090 zil_itx_destroy(itx); 1091 itx = zil_itx_create(TX_WRITE, sizeof (*lr)); 1092 lr = (lr_write_t *)&itx->itx_lr; 1093 wr_state = WR_NEED_COPY; 1094 } 1095 1096 itx->itx_wr_state = wr_state; 1097 lr->lr_foid = ZVOL_OBJ; 1098 lr->lr_offset = off; 1099 lr->lr_length = len; 1100 lr->lr_blkoff = 0; 1101 BP_ZERO(&lr->lr_blkptr); 1102 1103 itx->itx_private = zv; 1104 itx->itx_sync = sync; 1105 1106 zil_itx_assign(zilog, itx, tx); 1107 1108 off += len; 1109 resid -= len; 1110 } 1111 } 1112 1113 static int 1114 zvol_dumpio_vdev(vdev_t *vd, void *addr, uint64_t offset, uint64_t origoffset, 1115 uint64_t size, boolean_t doread, boolean_t isdump) 1116 { 1117 vdev_disk_t *dvd; 1118 int c; 1119 int numerrors = 0; 1120 1121 if (vd->vdev_ops == &vdev_mirror_ops || 1122 vd->vdev_ops == &vdev_replacing_ops || 1123 vd->vdev_ops == &vdev_spare_ops) { 1124 for (c = 0; c < vd->vdev_children; c++) { 1125 int err = zvol_dumpio_vdev(vd->vdev_child[c], 1126 addr, offset, origoffset, size, doread, isdump); 1127 if (err != 0) { 1128 numerrors++; 1129 } else if (doread) { 1130 break; 1131 } 1132 } 1133 } 1134 1135 if (!vd->vdev_ops->vdev_op_leaf && vd->vdev_ops != &vdev_raidz_ops) 1136 return (numerrors < vd->vdev_children ? 0 : EIO); 1137 1138 if (doread && !vdev_readable(vd)) 1139 return (SET_ERROR(EIO)); 1140 else if (!doread && !vdev_writeable(vd)) 1141 return (SET_ERROR(EIO)); 1142 1143 if (vd->vdev_ops == &vdev_raidz_ops) { 1144 return (vdev_raidz_physio(vd, 1145 addr, size, offset, origoffset, doread, isdump)); 1146 } 1147 1148 offset += VDEV_LABEL_START_SIZE; 1149 1150 if (ddi_in_panic() || isdump) { 1151 ASSERT(!doread); 1152 if (doread) 1153 return (SET_ERROR(EIO)); 1154 dvd = vd->vdev_tsd; 1155 ASSERT3P(dvd, !=, NULL); 1156 return (ldi_dump(dvd->vd_lh, addr, lbtodb(offset), 1157 lbtodb(size))); 1158 } else { 1159 dvd = vd->vdev_tsd; 1160 ASSERT3P(dvd, !=, NULL); 1161 return (vdev_disk_ldi_physio(dvd->vd_lh, addr, size, 1162 offset, doread ? B_READ : B_WRITE)); 1163 } 1164 } 1165 1166 static int 1167 zvol_dumpio(zvol_state_t *zv, void *addr, uint64_t offset, uint64_t size, 1168 boolean_t doread, boolean_t isdump) 1169 { 1170 vdev_t *vd; 1171 int error; 1172 zvol_extent_t *ze; 1173 spa_t *spa = dmu_objset_spa(zv->zv_objset); 1174 1175 /* Must be sector aligned, and not stradle a block boundary. */ 1176 if (P2PHASE(offset, DEV_BSIZE) || P2PHASE(size, DEV_BSIZE) || 1177 P2BOUNDARY(offset, size, zv->zv_volblocksize)) { 1178 return (SET_ERROR(EINVAL)); 1179 } 1180 ASSERT(size <= zv->zv_volblocksize); 1181 1182 /* Locate the extent this belongs to */ 1183 ze = list_head(&zv->zv_extents); 1184 while (offset >= ze->ze_nblks * zv->zv_volblocksize) { 1185 offset -= ze->ze_nblks * zv->zv_volblocksize; 1186 ze = list_next(&zv->zv_extents, ze); 1187 } 1188 1189 if (ze == NULL) 1190 return (SET_ERROR(EINVAL)); 1191 1192 if (!ddi_in_panic()) 1193 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER); 1194 1195 vd = vdev_lookup_top(spa, DVA_GET_VDEV(&ze->ze_dva)); 1196 offset += DVA_GET_OFFSET(&ze->ze_dva); 1197 error = zvol_dumpio_vdev(vd, addr, offset, DVA_GET_OFFSET(&ze->ze_dva), 1198 size, doread, isdump); 1199 1200 if (!ddi_in_panic()) 1201 spa_config_exit(spa, SCL_STATE, FTAG); 1202 1203 return (error); 1204 } 1205 1206 int 1207 zvol_strategy(buf_t *bp) 1208 { 1209 zfs_soft_state_t *zs = NULL; 1210 zvol_state_t *zv; 1211 uint64_t off, volsize; 1212 size_t resid; 1213 char *addr; 1214 objset_t *os; 1215 rl_t *rl; 1216 int error = 0; 1217 boolean_t doread = bp->b_flags & B_READ; 1218 boolean_t is_dumpified; 1219 boolean_t sync; 1220 1221 if (getminor(bp->b_edev) == 0) { 1222 error = SET_ERROR(EINVAL); 1223 } else { 1224 zs = ddi_get_soft_state(zfsdev_state, getminor(bp->b_edev)); 1225 if (zs == NULL) 1226 error = SET_ERROR(ENXIO); 1227 else if (zs->zss_type != ZSST_ZVOL) 1228 error = SET_ERROR(EINVAL); 1229 } 1230 1231 if (error) { 1232 bioerror(bp, error); 1233 biodone(bp); 1234 return (0); 1235 } 1236 1237 zv = zs->zss_data; 1238 1239 if (!(bp->b_flags & B_READ) && (zv->zv_flags & ZVOL_RDONLY)) { 1240 bioerror(bp, EROFS); 1241 biodone(bp); 1242 return (0); 1243 } 1244 1245 off = ldbtob(bp->b_blkno); 1246 volsize = zv->zv_volsize; 1247 1248 os = zv->zv_objset; 1249 ASSERT(os != NULL); 1250 1251 bp_mapin(bp); 1252 addr = bp->b_un.b_addr; 1253 resid = bp->b_bcount; 1254 1255 if (resid > 0 && (off < 0 || off >= volsize)) { 1256 bioerror(bp, EIO); 1257 biodone(bp); 1258 return (0); 1259 } 1260 1261 is_dumpified = zv->zv_flags & ZVOL_DUMPIFIED; 1262 sync = ((!(bp->b_flags & B_ASYNC) && 1263 !(zv->zv_flags & ZVOL_WCE)) || 1264 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)) && 1265 !doread && !is_dumpified; 1266 1267 /* 1268 * There must be no buffer changes when doing a dmu_sync() because 1269 * we can't change the data whilst calculating the checksum. 1270 */ 1271 rl = zfs_range_lock(&zv->zv_znode, off, resid, 1272 doread ? RL_READER : RL_WRITER); 1273 1274 while (resid != 0 && off < volsize) { 1275 size_t size = MIN(resid, zvol_maxphys); 1276 if (is_dumpified) { 1277 size = MIN(size, P2END(off, zv->zv_volblocksize) - off); 1278 error = zvol_dumpio(zv, addr, off, size, 1279 doread, B_FALSE); 1280 } else if (doread) { 1281 error = dmu_read(os, ZVOL_OBJ, off, size, addr, 1282 DMU_READ_PREFETCH); 1283 } else { 1284 dmu_tx_t *tx = dmu_tx_create(os); 1285 dmu_tx_hold_write(tx, ZVOL_OBJ, off, size); 1286 error = dmu_tx_assign(tx, TXG_WAIT); 1287 if (error) { 1288 dmu_tx_abort(tx); 1289 } else { 1290 dmu_write(os, ZVOL_OBJ, off, size, addr, tx); 1291 zvol_log_write(zv, tx, off, size, sync); 1292 dmu_tx_commit(tx); 1293 } 1294 } 1295 if (error) { 1296 /* convert checksum errors into IO errors */ 1297 if (error == ECKSUM) 1298 error = SET_ERROR(EIO); 1299 break; 1300 } 1301 off += size; 1302 addr += size; 1303 resid -= size; 1304 } 1305 zfs_range_unlock(rl); 1306 1307 if ((bp->b_resid = resid) == bp->b_bcount) 1308 bioerror(bp, off > volsize ? EINVAL : error); 1309 1310 if (sync) 1311 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1312 biodone(bp); 1313 1314 return (0); 1315 } 1316 1317 /* 1318 * Set the buffer count to the zvol maximum transfer. 1319 * Using our own routine instead of the default minphys() 1320 * means that for larger writes we write bigger buffers on X86 1321 * (128K instead of 56K) and flush the disk write cache less often 1322 * (every zvol_maxphys - currently 1MB) instead of minphys (currently 1323 * 56K on X86 and 128K on sparc). 1324 */ 1325 void 1326 zvol_minphys(struct buf *bp) 1327 { 1328 if (bp->b_bcount > zvol_maxphys) 1329 bp->b_bcount = zvol_maxphys; 1330 } 1331 1332 int 1333 zvol_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblocks) 1334 { 1335 minor_t minor = getminor(dev); 1336 zvol_state_t *zv; 1337 int error = 0; 1338 uint64_t size; 1339 uint64_t boff; 1340 uint64_t resid; 1341 1342 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1343 if (zv == NULL) 1344 return (SET_ERROR(ENXIO)); 1345 1346 if ((zv->zv_flags & ZVOL_DUMPIFIED) == 0) 1347 return (SET_ERROR(EINVAL)); 1348 1349 boff = ldbtob(blkno); 1350 resid = ldbtob(nblocks); 1351 1352 VERIFY3U(boff + resid, <=, zv->zv_volsize); 1353 1354 while (resid) { 1355 size = MIN(resid, P2END(boff, zv->zv_volblocksize) - boff); 1356 error = zvol_dumpio(zv, addr, boff, size, B_FALSE, B_TRUE); 1357 if (error) 1358 break; 1359 boff += size; 1360 addr += size; 1361 resid -= size; 1362 } 1363 1364 return (error); 1365 } 1366 1367 /*ARGSUSED*/ 1368 int 1369 zvol_read(dev_t dev, uio_t *uio, cred_t *cr) 1370 { 1371 minor_t minor = getminor(dev); 1372 zvol_state_t *zv; 1373 uint64_t volsize; 1374 rl_t *rl; 1375 int error = 0; 1376 1377 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1378 if (zv == NULL) 1379 return (SET_ERROR(ENXIO)); 1380 1381 volsize = zv->zv_volsize; 1382 if (uio->uio_resid > 0 && 1383 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize)) 1384 return (SET_ERROR(EIO)); 1385 1386 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1387 error = physio(zvol_strategy, NULL, dev, B_READ, 1388 zvol_minphys, uio); 1389 return (error); 1390 } 1391 1392 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid, 1393 RL_READER); 1394 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1395 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1396 1397 /* don't read past the end */ 1398 if (bytes > volsize - uio->uio_loffset) 1399 bytes = volsize - uio->uio_loffset; 1400 1401 error = dmu_read_uio(zv->zv_objset, ZVOL_OBJ, uio, bytes); 1402 if (error) { 1403 /* convert checksum errors into IO errors */ 1404 if (error == ECKSUM) 1405 error = SET_ERROR(EIO); 1406 break; 1407 } 1408 } 1409 zfs_range_unlock(rl); 1410 return (error); 1411 } 1412 1413 /*ARGSUSED*/ 1414 int 1415 zvol_write(dev_t dev, uio_t *uio, cred_t *cr) 1416 { 1417 minor_t minor = getminor(dev); 1418 zvol_state_t *zv; 1419 uint64_t volsize; 1420 rl_t *rl; 1421 int error = 0; 1422 boolean_t sync; 1423 1424 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1425 if (zv == NULL) 1426 return (SET_ERROR(ENXIO)); 1427 1428 volsize = zv->zv_volsize; 1429 if (uio->uio_resid > 0 && 1430 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize)) 1431 return (SET_ERROR(EIO)); 1432 1433 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1434 error = physio(zvol_strategy, NULL, dev, B_WRITE, 1435 zvol_minphys, uio); 1436 return (error); 1437 } 1438 1439 sync = !(zv->zv_flags & ZVOL_WCE) || 1440 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS); 1441 1442 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid, 1443 RL_WRITER); 1444 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1445 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1446 uint64_t off = uio->uio_loffset; 1447 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset); 1448 1449 if (bytes > volsize - off) /* don't write past the end */ 1450 bytes = volsize - off; 1451 1452 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes); 1453 error = dmu_tx_assign(tx, TXG_WAIT); 1454 if (error) { 1455 dmu_tx_abort(tx); 1456 break; 1457 } 1458 error = dmu_write_uio_dbuf(zv->zv_dbuf, uio, bytes, tx); 1459 if (error == 0) 1460 zvol_log_write(zv, tx, off, bytes, sync); 1461 dmu_tx_commit(tx); 1462 1463 if (error) 1464 break; 1465 } 1466 zfs_range_unlock(rl); 1467 if (sync) 1468 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1469 return (error); 1470 } 1471 1472 int 1473 zvol_getefi(void *arg, int flag, uint64_t vs, uint8_t bs) 1474 { 1475 struct uuid uuid = EFI_RESERVED; 1476 efi_gpe_t gpe = { 0 }; 1477 uint32_t crc; 1478 dk_efi_t efi; 1479 int length; 1480 char *ptr; 1481 1482 if (ddi_copyin(arg, &efi, sizeof (dk_efi_t), flag)) 1483 return (SET_ERROR(EFAULT)); 1484 ptr = (char *)(uintptr_t)efi.dki_data_64; 1485 length = efi.dki_length; 1486 /* 1487 * Some clients may attempt to request a PMBR for the 1488 * zvol. Currently this interface will return EINVAL to 1489 * such requests. These requests could be supported by 1490 * adding a check for lba == 0 and consing up an appropriate 1491 * PMBR. 1492 */ 1493 if (efi.dki_lba < 1 || efi.dki_lba > 2 || length <= 0) 1494 return (SET_ERROR(EINVAL)); 1495 1496 gpe.efi_gpe_StartingLBA = LE_64(34ULL); 1497 gpe.efi_gpe_EndingLBA = LE_64((vs >> bs) - 1); 1498 UUID_LE_CONVERT(gpe.efi_gpe_PartitionTypeGUID, uuid); 1499 1500 if (efi.dki_lba == 1) { 1501 efi_gpt_t gpt = { 0 }; 1502 1503 gpt.efi_gpt_Signature = LE_64(EFI_SIGNATURE); 1504 gpt.efi_gpt_Revision = LE_32(EFI_VERSION_CURRENT); 1505 gpt.efi_gpt_HeaderSize = LE_32(sizeof (gpt)); 1506 gpt.efi_gpt_MyLBA = LE_64(1ULL); 1507 gpt.efi_gpt_FirstUsableLBA = LE_64(34ULL); 1508 gpt.efi_gpt_LastUsableLBA = LE_64((vs >> bs) - 1); 1509 gpt.efi_gpt_PartitionEntryLBA = LE_64(2ULL); 1510 gpt.efi_gpt_NumberOfPartitionEntries = LE_32(1); 1511 gpt.efi_gpt_SizeOfPartitionEntry = 1512 LE_32(sizeof (efi_gpe_t)); 1513 CRC32(crc, &gpe, sizeof (gpe), -1U, crc32_table); 1514 gpt.efi_gpt_PartitionEntryArrayCRC32 = LE_32(~crc); 1515 CRC32(crc, &gpt, sizeof (gpt), -1U, crc32_table); 1516 gpt.efi_gpt_HeaderCRC32 = LE_32(~crc); 1517 if (ddi_copyout(&gpt, ptr, MIN(sizeof (gpt), length), 1518 flag)) 1519 return (SET_ERROR(EFAULT)); 1520 ptr += sizeof (gpt); 1521 length -= sizeof (gpt); 1522 } 1523 if (length > 0 && ddi_copyout(&gpe, ptr, MIN(sizeof (gpe), 1524 length), flag)) 1525 return (SET_ERROR(EFAULT)); 1526 return (0); 1527 } 1528 1529 /* 1530 * BEGIN entry points to allow external callers access to the volume. 1531 */ 1532 /* 1533 * Return the volume parameters needed for access from an external caller. 1534 * These values are invariant as long as the volume is held open. 1535 */ 1536 int 1537 zvol_get_volume_params(minor_t minor, uint64_t *blksize, 1538 uint64_t *max_xfer_len, void **minor_hdl, void **objset_hdl, void **zil_hdl, 1539 void **rl_hdl, void **bonus_hdl) 1540 { 1541 zvol_state_t *zv; 1542 1543 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1544 if (zv == NULL) 1545 return (SET_ERROR(ENXIO)); 1546 if (zv->zv_flags & ZVOL_DUMPIFIED) 1547 return (SET_ERROR(ENXIO)); 1548 1549 ASSERT(blksize && max_xfer_len && minor_hdl && 1550 objset_hdl && zil_hdl && rl_hdl && bonus_hdl); 1551 1552 *blksize = zv->zv_volblocksize; 1553 *max_xfer_len = (uint64_t)zvol_maxphys; 1554 *minor_hdl = zv; 1555 *objset_hdl = zv->zv_objset; 1556 *zil_hdl = zv->zv_zilog; 1557 *rl_hdl = &zv->zv_znode; 1558 *bonus_hdl = zv->zv_dbuf; 1559 return (0); 1560 } 1561 1562 /* 1563 * Return the current volume size to an external caller. 1564 * The size can change while the volume is open. 1565 */ 1566 uint64_t 1567 zvol_get_volume_size(void *minor_hdl) 1568 { 1569 zvol_state_t *zv = minor_hdl; 1570 1571 return (zv->zv_volsize); 1572 } 1573 1574 /* 1575 * Return the current WCE setting to an external caller. 1576 * The WCE setting can change while the volume is open. 1577 */ 1578 int 1579 zvol_get_volume_wce(void *minor_hdl) 1580 { 1581 zvol_state_t *zv = minor_hdl; 1582 1583 return ((zv->zv_flags & ZVOL_WCE) ? 1 : 0); 1584 } 1585 1586 /* 1587 * Entry point for external callers to zvol_log_write 1588 */ 1589 void 1590 zvol_log_write_minor(void *minor_hdl, dmu_tx_t *tx, offset_t off, ssize_t resid, 1591 boolean_t sync) 1592 { 1593 zvol_state_t *zv = minor_hdl; 1594 1595 zvol_log_write(zv, tx, off, resid, sync); 1596 } 1597 /* 1598 * END entry points to allow external callers access to the volume. 1599 */ 1600 1601 /* 1602 * Log a DKIOCFREE/free-long-range to the ZIL with TX_TRUNCATE. 1603 */ 1604 static void 1605 zvol_log_truncate(zvol_state_t *zv, dmu_tx_t *tx, uint64_t off, uint64_t len, 1606 boolean_t sync) 1607 { 1608 itx_t *itx; 1609 lr_truncate_t *lr; 1610 zilog_t *zilog = zv->zv_zilog; 1611 1612 if (zil_replaying(zilog, tx)) 1613 return; 1614 1615 itx = zil_itx_create(TX_TRUNCATE, sizeof (*lr)); 1616 lr = (lr_truncate_t *)&itx->itx_lr; 1617 lr->lr_foid = ZVOL_OBJ; 1618 lr->lr_offset = off; 1619 lr->lr_length = len; 1620 1621 itx->itx_sync = sync; 1622 zil_itx_assign(zilog, itx, tx); 1623 } 1624 1625 /* 1626 * Dirtbag ioctls to support mkfs(1M) for UFS filesystems. See dkio(7I). 1627 * Also a dirtbag dkio ioctl for unmap/free-block functionality. 1628 */ 1629 /*ARGSUSED*/ 1630 int 1631 zvol_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp) 1632 { 1633 zvol_state_t *zv; 1634 struct dk_callback *dkc; 1635 int error = 0; 1636 rl_t *rl; 1637 1638 mutex_enter(&zfsdev_state_lock); 1639 1640 zv = zfsdev_get_soft_state(getminor(dev), ZSST_ZVOL); 1641 1642 if (zv == NULL) { 1643 mutex_exit(&zfsdev_state_lock); 1644 return (SET_ERROR(ENXIO)); 1645 } 1646 ASSERT(zv->zv_total_opens > 0); 1647 1648 switch (cmd) { 1649 1650 case DKIOCINFO: 1651 { 1652 struct dk_cinfo dki; 1653 1654 bzero(&dki, sizeof (dki)); 1655 (void) strcpy(dki.dki_cname, "zvol"); 1656 (void) strcpy(dki.dki_dname, "zvol"); 1657 dki.dki_ctype = DKC_UNKNOWN; 1658 dki.dki_unit = getminor(dev); 1659 dki.dki_maxtransfer = 1660 1 << (SPA_OLD_MAXBLOCKSHIFT - zv->zv_min_bs); 1661 mutex_exit(&zfsdev_state_lock); 1662 if (ddi_copyout(&dki, (void *)arg, sizeof (dki), flag)) 1663 error = SET_ERROR(EFAULT); 1664 return (error); 1665 } 1666 1667 case DKIOCGMEDIAINFO: 1668 { 1669 struct dk_minfo dkm; 1670 1671 bzero(&dkm, sizeof (dkm)); 1672 dkm.dki_lbsize = 1U << zv->zv_min_bs; 1673 dkm.dki_capacity = zv->zv_volsize >> zv->zv_min_bs; 1674 dkm.dki_media_type = DK_UNKNOWN; 1675 mutex_exit(&zfsdev_state_lock); 1676 if (ddi_copyout(&dkm, (void *)arg, sizeof (dkm), flag)) 1677 error = SET_ERROR(EFAULT); 1678 return (error); 1679 } 1680 1681 case DKIOCGMEDIAINFOEXT: 1682 { 1683 struct dk_minfo_ext dkmext; 1684 1685 bzero(&dkmext, sizeof (dkmext)); 1686 dkmext.dki_lbsize = 1U << zv->zv_min_bs; 1687 dkmext.dki_pbsize = zv->zv_volblocksize; 1688 dkmext.dki_capacity = zv->zv_volsize >> zv->zv_min_bs; 1689 dkmext.dki_media_type = DK_UNKNOWN; 1690 mutex_exit(&zfsdev_state_lock); 1691 if (ddi_copyout(&dkmext, (void *)arg, sizeof (dkmext), flag)) 1692 error = SET_ERROR(EFAULT); 1693 return (error); 1694 } 1695 1696 case DKIOCGETEFI: 1697 { 1698 uint64_t vs = zv->zv_volsize; 1699 uint8_t bs = zv->zv_min_bs; 1700 1701 mutex_exit(&zfsdev_state_lock); 1702 error = zvol_getefi((void *)arg, flag, vs, bs); 1703 return (error); 1704 } 1705 1706 case DKIOCFLUSHWRITECACHE: 1707 dkc = (struct dk_callback *)arg; 1708 mutex_exit(&zfsdev_state_lock); 1709 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1710 if ((flag & FKIOCTL) && dkc != NULL && dkc->dkc_callback) { 1711 (*dkc->dkc_callback)(dkc->dkc_cookie, error); 1712 error = 0; 1713 } 1714 return (error); 1715 1716 case DKIOCGETWCE: 1717 { 1718 int wce = (zv->zv_flags & ZVOL_WCE) ? 1 : 0; 1719 if (ddi_copyout(&wce, (void *)arg, sizeof (int), 1720 flag)) 1721 error = SET_ERROR(EFAULT); 1722 break; 1723 } 1724 case DKIOCSETWCE: 1725 { 1726 int wce; 1727 if (ddi_copyin((void *)arg, &wce, sizeof (int), 1728 flag)) { 1729 error = SET_ERROR(EFAULT); 1730 break; 1731 } 1732 if (wce) { 1733 zv->zv_flags |= ZVOL_WCE; 1734 mutex_exit(&zfsdev_state_lock); 1735 } else { 1736 zv->zv_flags &= ~ZVOL_WCE; 1737 mutex_exit(&zfsdev_state_lock); 1738 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1739 } 1740 return (0); 1741 } 1742 1743 case DKIOCGGEOM: 1744 case DKIOCGVTOC: 1745 /* 1746 * commands using these (like prtvtoc) expect ENOTSUP 1747 * since we're emulating an EFI label 1748 */ 1749 error = SET_ERROR(ENOTSUP); 1750 break; 1751 1752 case DKIOCDUMPINIT: 1753 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize, 1754 RL_WRITER); 1755 error = zvol_dumpify(zv); 1756 zfs_range_unlock(rl); 1757 break; 1758 1759 case DKIOCDUMPFINI: 1760 if (!(zv->zv_flags & ZVOL_DUMPIFIED)) 1761 break; 1762 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize, 1763 RL_WRITER); 1764 error = zvol_dump_fini(zv); 1765 zfs_range_unlock(rl); 1766 break; 1767 1768 case DKIOCFREE: 1769 { 1770 dkioc_free_t df; 1771 dmu_tx_t *tx; 1772 1773 if (!zvol_unmap_enabled) 1774 break; 1775 1776 if (ddi_copyin((void *)arg, &df, sizeof (df), flag)) { 1777 error = SET_ERROR(EFAULT); 1778 break; 1779 } 1780 1781 /* 1782 * Apply Postel's Law to length-checking. If they overshoot, 1783 * just blank out until the end, if there's a need to blank 1784 * out anything. 1785 */ 1786 if (df.df_start >= zv->zv_volsize) 1787 break; /* No need to do anything... */ 1788 1789 mutex_exit(&zfsdev_state_lock); 1790 1791 rl = zfs_range_lock(&zv->zv_znode, df.df_start, df.df_length, 1792 RL_WRITER); 1793 tx = dmu_tx_create(zv->zv_objset); 1794 dmu_tx_mark_netfree(tx); 1795 error = dmu_tx_assign(tx, TXG_WAIT); 1796 if (error != 0) { 1797 dmu_tx_abort(tx); 1798 } else { 1799 zvol_log_truncate(zv, tx, df.df_start, 1800 df.df_length, B_TRUE); 1801 dmu_tx_commit(tx); 1802 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 1803 df.df_start, df.df_length); 1804 } 1805 1806 zfs_range_unlock(rl); 1807 1808 /* 1809 * If the write-cache is disabled, 'sync' property 1810 * is set to 'always', or if the caller is asking for 1811 * a synchronous free, commit this operation to the zil. 1812 * This will sync any previous uncommitted writes to the 1813 * zvol object. 1814 * Can be overridden by the zvol_unmap_sync_enabled tunable. 1815 */ 1816 if ((error == 0) && zvol_unmap_sync_enabled && 1817 (!(zv->zv_flags & ZVOL_WCE) || 1818 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS) || 1819 (df.df_flags & DF_WAIT_SYNC))) { 1820 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1821 } 1822 1823 return (error); 1824 } 1825 1826 default: 1827 error = SET_ERROR(ENOTTY); 1828 break; 1829 1830 } 1831 mutex_exit(&zfsdev_state_lock); 1832 return (error); 1833 } 1834 1835 int 1836 zvol_busy(void) 1837 { 1838 return (zvol_minors != 0); 1839 } 1840 1841 void 1842 zvol_init(void) 1843 { 1844 VERIFY(ddi_soft_state_init(&zfsdev_state, sizeof (zfs_soft_state_t), 1845 1) == 0); 1846 mutex_init(&zfsdev_state_lock, NULL, MUTEX_DEFAULT, NULL); 1847 } 1848 1849 void 1850 zvol_fini(void) 1851 { 1852 mutex_destroy(&zfsdev_state_lock); 1853 ddi_soft_state_fini(&zfsdev_state); 1854 } 1855 1856 /*ARGSUSED*/ 1857 static int 1858 zfs_mvdev_dump_feature_check(void *arg, dmu_tx_t *tx) 1859 { 1860 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 1861 1862 if (spa_feature_is_active(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP)) 1863 return (1); 1864 return (0); 1865 } 1866 1867 /*ARGSUSED*/ 1868 static void 1869 zfs_mvdev_dump_activate_feature_sync(void *arg, dmu_tx_t *tx) 1870 { 1871 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 1872 1873 spa_feature_incr(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP, tx); 1874 } 1875 1876 static int 1877 zvol_dump_init(zvol_state_t *zv, boolean_t resize) 1878 { 1879 dmu_tx_t *tx; 1880 int error; 1881 objset_t *os = zv->zv_objset; 1882 spa_t *spa = dmu_objset_spa(os); 1883 vdev_t *vd = spa->spa_root_vdev; 1884 nvlist_t *nv = NULL; 1885 uint64_t version = spa_version(spa); 1886 uint64_t checksum, compress, refresrv, vbs, dedup; 1887 1888 ASSERT(MUTEX_HELD(&zfsdev_state_lock)); 1889 ASSERT(vd->vdev_ops == &vdev_root_ops); 1890 1891 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 0, 1892 DMU_OBJECT_END); 1893 if (error != 0) 1894 return (error); 1895 /* wait for dmu_free_long_range to actually free the blocks */ 1896 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 1897 1898 /* 1899 * If the pool on which the dump device is being initialized has more 1900 * than one child vdev, check that the MULTI_VDEV_CRASH_DUMP feature is 1901 * enabled. If so, bump that feature's counter to indicate that the 1902 * feature is active. We also check the vdev type to handle the 1903 * following case: 1904 * # zpool create test raidz disk1 disk2 disk3 1905 * Now have spa_root_vdev->vdev_children == 1 (the raidz vdev), 1906 * the raidz vdev itself has 3 children. 1907 */ 1908 if (vd->vdev_children > 1 || vd->vdev_ops == &vdev_raidz_ops) { 1909 if (!spa_feature_is_enabled(spa, 1910 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP)) 1911 return (SET_ERROR(ENOTSUP)); 1912 (void) dsl_sync_task(spa_name(spa), 1913 zfs_mvdev_dump_feature_check, 1914 zfs_mvdev_dump_activate_feature_sync, NULL, 1915 2, ZFS_SPACE_CHECK_RESERVED); 1916 } 1917 1918 if (!resize) { 1919 error = dsl_prop_get_integer(zv->zv_name, 1920 zfs_prop_to_name(ZFS_PROP_COMPRESSION), &compress, NULL); 1921 if (error == 0) { 1922 error = dsl_prop_get_integer(zv->zv_name, 1923 zfs_prop_to_name(ZFS_PROP_CHECKSUM), &checksum, 1924 NULL); 1925 } 1926 if (error == 0) { 1927 error = dsl_prop_get_integer(zv->zv_name, 1928 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 1929 &refresrv, NULL); 1930 } 1931 if (error == 0) { 1932 error = dsl_prop_get_integer(zv->zv_name, 1933 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &vbs, 1934 NULL); 1935 } 1936 if (version >= SPA_VERSION_DEDUP && error == 0) { 1937 error = dsl_prop_get_integer(zv->zv_name, 1938 zfs_prop_to_name(ZFS_PROP_DEDUP), &dedup, NULL); 1939 } 1940 } 1941 if (error != 0) 1942 return (error); 1943 1944 tx = dmu_tx_create(os); 1945 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 1946 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 1947 error = dmu_tx_assign(tx, TXG_WAIT); 1948 if (error != 0) { 1949 dmu_tx_abort(tx); 1950 return (error); 1951 } 1952 1953 /* 1954 * If we are resizing the dump device then we only need to 1955 * update the refreservation to match the newly updated 1956 * zvolsize. Otherwise, we save off the original state of the 1957 * zvol so that we can restore them if the zvol is ever undumpified. 1958 */ 1959 if (resize) { 1960 error = zap_update(os, ZVOL_ZAP_OBJ, 1961 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 1962 &zv->zv_volsize, tx); 1963 } else { 1964 error = zap_update(os, ZVOL_ZAP_OBJ, 1965 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, 1966 &compress, tx); 1967 if (error == 0) { 1968 error = zap_update(os, ZVOL_ZAP_OBJ, 1969 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, 1970 &checksum, tx); 1971 } 1972 if (error == 0) { 1973 error = zap_update(os, ZVOL_ZAP_OBJ, 1974 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 1975 &refresrv, tx); 1976 } 1977 if (error == 0) { 1978 error = zap_update(os, ZVOL_ZAP_OBJ, 1979 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, 1980 &vbs, tx); 1981 } 1982 if (error == 0) { 1983 error = dmu_object_set_blocksize( 1984 os, ZVOL_OBJ, SPA_OLD_MAXBLOCKSIZE, 0, tx); 1985 } 1986 if (version >= SPA_VERSION_DEDUP && error == 0) { 1987 error = zap_update(os, ZVOL_ZAP_OBJ, 1988 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, 1989 &dedup, tx); 1990 } 1991 if (error == 0) 1992 zv->zv_volblocksize = SPA_OLD_MAXBLOCKSIZE; 1993 } 1994 dmu_tx_commit(tx); 1995 1996 /* 1997 * We only need update the zvol's property if we are initializing 1998 * the dump area for the first time. 1999 */ 2000 if (error == 0 && !resize) { 2001 /* 2002 * If MULTI_VDEV_CRASH_DUMP is active, use the NOPARITY checksum 2003 * function. Otherwise, use the old default -- OFF. 2004 */ 2005 checksum = spa_feature_is_active(spa, 2006 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP) ? ZIO_CHECKSUM_NOPARITY : 2007 ZIO_CHECKSUM_OFF; 2008 2009 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 2010 VERIFY(nvlist_add_uint64(nv, 2011 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 0) == 0); 2012 VERIFY(nvlist_add_uint64(nv, 2013 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 2014 ZIO_COMPRESS_OFF) == 0); 2015 VERIFY(nvlist_add_uint64(nv, 2016 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 2017 checksum) == 0); 2018 if (version >= SPA_VERSION_DEDUP) { 2019 VERIFY(nvlist_add_uint64(nv, 2020 zfs_prop_to_name(ZFS_PROP_DEDUP), 2021 ZIO_CHECKSUM_OFF) == 0); 2022 } 2023 2024 error = zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL, 2025 nv, NULL); 2026 nvlist_free(nv); 2027 } 2028 2029 /* Allocate the space for the dump */ 2030 if (error == 0) 2031 error = zvol_prealloc(zv); 2032 return (error); 2033 } 2034 2035 static int 2036 zvol_dumpify(zvol_state_t *zv) 2037 { 2038 int error = 0; 2039 uint64_t dumpsize = 0; 2040 dmu_tx_t *tx; 2041 objset_t *os = zv->zv_objset; 2042 2043 if (zv->zv_flags & ZVOL_RDONLY) 2044 return (SET_ERROR(EROFS)); 2045 2046 if (zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 2047 8, 1, &dumpsize) != 0 || dumpsize != zv->zv_volsize) { 2048 boolean_t resize = (dumpsize > 0); 2049 2050 if ((error = zvol_dump_init(zv, resize)) != 0) { 2051 (void) zvol_dump_fini(zv); 2052 return (error); 2053 } 2054 } 2055 2056 /* 2057 * Build up our lba mapping. 2058 */ 2059 error = zvol_get_lbas(zv); 2060 if (error) { 2061 (void) zvol_dump_fini(zv); 2062 return (error); 2063 } 2064 2065 tx = dmu_tx_create(os); 2066 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 2067 error = dmu_tx_assign(tx, TXG_WAIT); 2068 if (error) { 2069 dmu_tx_abort(tx); 2070 (void) zvol_dump_fini(zv); 2071 return (error); 2072 } 2073 2074 zv->zv_flags |= ZVOL_DUMPIFIED; 2075 error = zap_update(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 8, 1, 2076 &zv->zv_volsize, tx); 2077 dmu_tx_commit(tx); 2078 2079 if (error) { 2080 (void) zvol_dump_fini(zv); 2081 return (error); 2082 } 2083 2084 txg_wait_synced(dmu_objset_pool(os), 0); 2085 return (0); 2086 } 2087 2088 static int 2089 zvol_dump_fini(zvol_state_t *zv) 2090 { 2091 dmu_tx_t *tx; 2092 objset_t *os = zv->zv_objset; 2093 nvlist_t *nv; 2094 int error = 0; 2095 uint64_t checksum, compress, refresrv, vbs, dedup; 2096 uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset)); 2097 2098 /* 2099 * Attempt to restore the zvol back to its pre-dumpified state. 2100 * This is a best-effort attempt as it's possible that not all 2101 * of these properties were initialized during the dumpify process 2102 * (i.e. error during zvol_dump_init). 2103 */ 2104 2105 tx = dmu_tx_create(os); 2106 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 2107 error = dmu_tx_assign(tx, TXG_WAIT); 2108 if (error) { 2109 dmu_tx_abort(tx); 2110 return (error); 2111 } 2112 (void) zap_remove(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, tx); 2113 dmu_tx_commit(tx); 2114 2115 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2116 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum); 2117 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2118 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, &compress); 2119 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2120 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, &refresrv); 2121 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2122 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, &vbs); 2123 2124 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 2125 (void) nvlist_add_uint64(nv, 2126 zfs_prop_to_name(ZFS_PROP_CHECKSUM), checksum); 2127 (void) nvlist_add_uint64(nv, 2128 zfs_prop_to_name(ZFS_PROP_COMPRESSION), compress); 2129 (void) nvlist_add_uint64(nv, 2130 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), refresrv); 2131 if (version >= SPA_VERSION_DEDUP && 2132 zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2133 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, &dedup) == 0) { 2134 (void) nvlist_add_uint64(nv, 2135 zfs_prop_to_name(ZFS_PROP_DEDUP), dedup); 2136 } 2137 (void) zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL, 2138 nv, NULL); 2139 nvlist_free(nv); 2140 2141 zvol_free_extents(zv); 2142 zv->zv_flags &= ~ZVOL_DUMPIFIED; 2143 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, DMU_OBJECT_END); 2144 /* wait for dmu_free_long_range to actually free the blocks */ 2145 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 2146 tx = dmu_tx_create(os); 2147 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 2148 error = dmu_tx_assign(tx, TXG_WAIT); 2149 if (error) { 2150 dmu_tx_abort(tx); 2151 return (error); 2152 } 2153 if (dmu_object_set_blocksize(os, ZVOL_OBJ, vbs, 0, tx) == 0) 2154 zv->zv_volblocksize = vbs; 2155 dmu_tx_commit(tx); 2156 2157 return (0); 2158 } 2159