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