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 2010 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 /* 27 * ZFS volume emulation driver. 28 * 29 * Makes a DMU object look like a volume of arbitrary size, up to 2^64 bytes. 30 * Volumes are accessed through the symbolic links named: 31 * 32 * /dev/zvol/dsk/<pool_name>/<dataset_name> 33 * /dev/zvol/rdsk/<pool_name>/<dataset_name> 34 * 35 * These links are created by the /dev filesystem (sdev_zvolops.c). 36 * Volumes are persistent through reboot. No user command needs to be 37 * run before opening and using a device. 38 */ 39 40 #include <sys/types.h> 41 #include <sys/param.h> 42 #include <sys/errno.h> 43 #include <sys/uio.h> 44 #include <sys/buf.h> 45 #include <sys/modctl.h> 46 #include <sys/open.h> 47 #include <sys/kmem.h> 48 #include <sys/conf.h> 49 #include <sys/cmn_err.h> 50 #include <sys/stat.h> 51 #include <sys/zap.h> 52 #include <sys/spa.h> 53 #include <sys/zio.h> 54 #include <sys/dmu_traverse.h> 55 #include <sys/dnode.h> 56 #include <sys/dsl_dataset.h> 57 #include <sys/dsl_prop.h> 58 #include <sys/dkio.h> 59 #include <sys/efi_partition.h> 60 #include <sys/byteorder.h> 61 #include <sys/pathname.h> 62 #include <sys/ddi.h> 63 #include <sys/sunddi.h> 64 #include <sys/crc32.h> 65 #include <sys/dirent.h> 66 #include <sys/policy.h> 67 #include <sys/fs/zfs.h> 68 #include <sys/zfs_ioctl.h> 69 #include <sys/mkdev.h> 70 #include <sys/zil.h> 71 #include <sys/refcount.h> 72 #include <sys/zfs_znode.h> 73 #include <sys/zfs_rlock.h> 74 #include <sys/vdev_disk.h> 75 #include <sys/vdev_impl.h> 76 #include <sys/zvol.h> 77 #include <sys/dumphdr.h> 78 #include <sys/zil_impl.h> 79 80 #include "zfs_namecheck.h" 81 82 static void *zvol_state; 83 static char *zvol_tag = "zvol_tag"; 84 85 #define ZVOL_DUMPSIZE "dumpsize" 86 87 /* 88 * This lock protects the zvol_state structure from being modified 89 * while it's being used, e.g. an open that comes in before a create 90 * finishes. It also protects temporary opens of the dataset so that, 91 * e.g., an open doesn't get a spurious EBUSY. 92 */ 93 static kmutex_t zvol_state_lock; 94 static uint32_t zvol_minors; 95 96 typedef struct zvol_extent { 97 list_node_t ze_node; 98 dva_t ze_dva; /* dva associated with this extent */ 99 uint64_t ze_nblks; /* number of blocks in extent */ 100 } zvol_extent_t; 101 102 /* 103 * The in-core state of each volume. 104 */ 105 typedef struct zvol_state { 106 char zv_name[MAXPATHLEN]; /* pool/dd name */ 107 uint64_t zv_volsize; /* amount of space we advertise */ 108 uint64_t zv_volblocksize; /* volume block size */ 109 minor_t zv_minor; /* minor number */ 110 uint8_t zv_min_bs; /* minimum addressable block shift */ 111 uint8_t zv_flags; /* readonly, dumpified, etc. */ 112 objset_t *zv_objset; /* objset handle */ 113 uint32_t zv_open_count[OTYPCNT]; /* open counts */ 114 uint32_t zv_total_opens; /* total open count */ 115 zilog_t *zv_zilog; /* ZIL handle */ 116 list_t zv_extents; /* List of extents for dump */ 117 znode_t zv_znode; /* for range locking */ 118 } zvol_state_t; 119 120 /* 121 * zvol specific flags 122 */ 123 #define ZVOL_RDONLY 0x1 124 #define ZVOL_DUMPIFIED 0x2 125 #define ZVOL_EXCL 0x4 126 #define ZVOL_WCE 0x8 127 128 /* 129 * zvol maximum transfer in one DMU tx. 130 */ 131 int zvol_maxphys = DMU_MAX_ACCESS/2; 132 133 extern int zfs_set_prop_nvlist(const char *, zprop_source_t, 134 nvlist_t *, nvlist_t **); 135 static int zvol_remove_zv(zvol_state_t *); 136 static int zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio); 137 static int zvol_dumpify(zvol_state_t *zv); 138 static int zvol_dump_fini(zvol_state_t *zv); 139 static int zvol_dump_init(zvol_state_t *zv, boolean_t resize); 140 141 static void 142 zvol_size_changed(uint64_t volsize, major_t maj, minor_t min) 143 { 144 dev_t dev = makedevice(maj, min); 145 146 VERIFY(ddi_prop_update_int64(dev, zfs_dip, 147 "Size", volsize) == DDI_SUCCESS); 148 VERIFY(ddi_prop_update_int64(dev, zfs_dip, 149 "Nblocks", lbtodb(volsize)) == DDI_SUCCESS); 150 151 /* Notify specfs to invalidate the cached size */ 152 spec_size_invalidate(dev, VBLK); 153 spec_size_invalidate(dev, VCHR); 154 } 155 156 int 157 zvol_check_volsize(uint64_t volsize, uint64_t blocksize) 158 { 159 if (volsize == 0) 160 return (EINVAL); 161 162 if (volsize % blocksize != 0) 163 return (EINVAL); 164 165 #ifdef _ILP32 166 if (volsize - 1 > SPEC_MAXOFFSET_T) 167 return (EOVERFLOW); 168 #endif 169 return (0); 170 } 171 172 int 173 zvol_check_volblocksize(uint64_t volblocksize) 174 { 175 if (volblocksize < SPA_MINBLOCKSIZE || 176 volblocksize > SPA_MAXBLOCKSIZE || 177 !ISP2(volblocksize)) 178 return (EDOM); 179 180 return (0); 181 } 182 183 int 184 zvol_get_stats(objset_t *os, nvlist_t *nv) 185 { 186 int error; 187 dmu_object_info_t doi; 188 uint64_t val; 189 190 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val); 191 if (error) 192 return (error); 193 194 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val); 195 196 error = dmu_object_info(os, ZVOL_OBJ, &doi); 197 198 if (error == 0) { 199 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE, 200 doi.doi_data_block_size); 201 } 202 203 return (error); 204 } 205 206 /* 207 * Find a free minor number. 208 */ 209 static minor_t 210 zvol_minor_alloc(void) 211 { 212 minor_t minor; 213 214 ASSERT(MUTEX_HELD(&zvol_state_lock)); 215 216 for (minor = 1; minor <= ZVOL_MAX_MINOR; minor++) 217 if (ddi_get_soft_state(zvol_state, minor) == NULL) 218 return (minor); 219 220 return (0); 221 } 222 223 static zvol_state_t * 224 zvol_minor_lookup(const char *name) 225 { 226 minor_t minor; 227 zvol_state_t *zv; 228 229 ASSERT(MUTEX_HELD(&zvol_state_lock)); 230 231 for (minor = 1; minor <= ZVOL_MAX_MINOR; minor++) { 232 zv = ddi_get_soft_state(zvol_state, minor); 233 if (zv == NULL) 234 continue; 235 if (strcmp(zv->zv_name, name) == 0) 236 break; 237 } 238 239 return (zv); 240 } 241 242 /* extent mapping arg */ 243 struct maparg { 244 zvol_state_t *ma_zv; 245 uint64_t ma_blks; 246 }; 247 248 /*ARGSUSED*/ 249 static int 250 zvol_map_block(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, 251 const zbookmark_t *zb, const dnode_phys_t *dnp, void *arg) 252 { 253 struct maparg *ma = arg; 254 zvol_extent_t *ze; 255 int bs = ma->ma_zv->zv_volblocksize; 256 257 if (bp == NULL || zb->zb_object != ZVOL_OBJ || zb->zb_level != 0) 258 return (0); 259 260 VERIFY3U(ma->ma_blks, ==, zb->zb_blkid); 261 ma->ma_blks++; 262 263 /* Abort immediately if we have encountered gang blocks */ 264 if (BP_IS_GANG(bp)) 265 return (EFRAGS); 266 267 /* 268 * See if the block is at the end of the previous extent. 269 */ 270 ze = list_tail(&ma->ma_zv->zv_extents); 271 if (ze && 272 DVA_GET_VDEV(BP_IDENTITY(bp)) == DVA_GET_VDEV(&ze->ze_dva) && 273 DVA_GET_OFFSET(BP_IDENTITY(bp)) == 274 DVA_GET_OFFSET(&ze->ze_dva) + ze->ze_nblks * bs) { 275 ze->ze_nblks++; 276 return (0); 277 } 278 279 dprintf_bp(bp, "%s", "next blkptr:"); 280 281 /* start a new extent */ 282 ze = kmem_zalloc(sizeof (zvol_extent_t), KM_SLEEP); 283 ze->ze_dva = bp->blk_dva[0]; /* structure assignment */ 284 ze->ze_nblks = 1; 285 list_insert_tail(&ma->ma_zv->zv_extents, ze); 286 return (0); 287 } 288 289 static void 290 zvol_free_extents(zvol_state_t *zv) 291 { 292 zvol_extent_t *ze; 293 294 while (ze = list_head(&zv->zv_extents)) { 295 list_remove(&zv->zv_extents, ze); 296 kmem_free(ze, sizeof (zvol_extent_t)); 297 } 298 } 299 300 static int 301 zvol_get_lbas(zvol_state_t *zv) 302 { 303 struct maparg ma; 304 int err; 305 306 ma.ma_zv = zv; 307 ma.ma_blks = 0; 308 zvol_free_extents(zv); 309 310 err = traverse_dataset(dmu_objset_ds(zv->zv_objset), 0, 311 TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA, zvol_map_block, &ma); 312 if (err || ma.ma_blks != (zv->zv_volsize / zv->zv_volblocksize)) { 313 zvol_free_extents(zv); 314 return (err ? err : EIO); 315 } 316 317 return (0); 318 } 319 320 /* ARGSUSED */ 321 void 322 zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx) 323 { 324 zfs_creat_t *zct = arg; 325 nvlist_t *nvprops = zct->zct_props; 326 int error; 327 uint64_t volblocksize, volsize; 328 329 VERIFY(nvlist_lookup_uint64(nvprops, 330 zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0); 331 if (nvlist_lookup_uint64(nvprops, 332 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0) 333 volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE); 334 335 /* 336 * These properties must be removed from the list so the generic 337 * property setting step won't apply to them. 338 */ 339 VERIFY(nvlist_remove_all(nvprops, 340 zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0); 341 (void) nvlist_remove_all(nvprops, 342 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE)); 343 344 error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize, 345 DMU_OT_NONE, 0, tx); 346 ASSERT(error == 0); 347 348 error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP, 349 DMU_OT_NONE, 0, tx); 350 ASSERT(error == 0); 351 352 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx); 353 ASSERT(error == 0); 354 } 355 356 /* 357 * Replay a TX_WRITE ZIL transaction that didn't get committed 358 * after a system failure 359 */ 360 static int 361 zvol_replay_write(zvol_state_t *zv, lr_write_t *lr, boolean_t byteswap) 362 { 363 objset_t *os = zv->zv_objset; 364 char *data = (char *)(lr + 1); /* data follows lr_write_t */ 365 uint64_t offset, length; 366 dmu_tx_t *tx; 367 int error; 368 369 if (byteswap) 370 byteswap_uint64_array(lr, sizeof (*lr)); 371 372 offset = lr->lr_offset; 373 length = lr->lr_length; 374 375 /* If it's a dmu_sync() block, write the whole block */ 376 if (lr->lr_common.lrc_reclen == sizeof (lr_write_t)) { 377 uint64_t blocksize = BP_GET_LSIZE(&lr->lr_blkptr); 378 if (length < blocksize) { 379 offset -= offset % blocksize; 380 length = blocksize; 381 } 382 } 383 384 tx = dmu_tx_create(os); 385 dmu_tx_hold_write(tx, ZVOL_OBJ, offset, length); 386 error = dmu_tx_assign(tx, TXG_WAIT); 387 if (error) { 388 dmu_tx_abort(tx); 389 } else { 390 dmu_write(os, ZVOL_OBJ, offset, length, data, tx); 391 dmu_tx_commit(tx); 392 } 393 394 return (error); 395 } 396 397 /* ARGSUSED */ 398 static int 399 zvol_replay_err(zvol_state_t *zv, lr_t *lr, boolean_t byteswap) 400 { 401 return (ENOTSUP); 402 } 403 404 /* 405 * Callback vectors for replaying records. 406 * Only TX_WRITE is needed for zvol. 407 */ 408 zil_replay_func_t *zvol_replay_vector[TX_MAX_TYPE] = { 409 zvol_replay_err, /* 0 no such transaction type */ 410 zvol_replay_err, /* TX_CREATE */ 411 zvol_replay_err, /* TX_MKDIR */ 412 zvol_replay_err, /* TX_MKXATTR */ 413 zvol_replay_err, /* TX_SYMLINK */ 414 zvol_replay_err, /* TX_REMOVE */ 415 zvol_replay_err, /* TX_RMDIR */ 416 zvol_replay_err, /* TX_LINK */ 417 zvol_replay_err, /* TX_RENAME */ 418 zvol_replay_write, /* TX_WRITE */ 419 zvol_replay_err, /* TX_TRUNCATE */ 420 zvol_replay_err, /* TX_SETATTR */ 421 zvol_replay_err, /* TX_ACL */ 422 zvol_replay_err, /* TX_CREATE_ACL */ 423 zvol_replay_err, /* TX_CREATE_ATTR */ 424 zvol_replay_err, /* TX_CREATE_ACL_ATTR */ 425 zvol_replay_err, /* TX_MKDIR_ACL */ 426 zvol_replay_err, /* TX_MKDIR_ATTR */ 427 zvol_replay_err, /* TX_MKDIR_ACL_ATTR */ 428 zvol_replay_err, /* TX_WRITE2 */ 429 }; 430 431 int 432 zvol_name2minor(const char *name, minor_t *minor) 433 { 434 zvol_state_t *zv; 435 436 mutex_enter(&zvol_state_lock); 437 zv = zvol_minor_lookup(name); 438 if (minor && zv) 439 *minor = zv->zv_minor; 440 mutex_exit(&zvol_state_lock); 441 return (zv ? 0 : -1); 442 } 443 444 /* 445 * Create a minor node (plus a whole lot more) for the specified volume. 446 */ 447 int 448 zvol_create_minor(const char *name) 449 { 450 zvol_state_t *zv; 451 objset_t *os; 452 dmu_object_info_t doi; 453 minor_t minor = 0; 454 char chrbuf[30], blkbuf[30]; 455 int error; 456 457 mutex_enter(&zvol_state_lock); 458 459 if (zvol_minor_lookup(name) != NULL) { 460 mutex_exit(&zvol_state_lock); 461 return (EEXIST); 462 } 463 464 /* lie and say we're read-only */ 465 error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, zvol_tag, &os); 466 467 if (error) { 468 mutex_exit(&zvol_state_lock); 469 return (error); 470 } 471 472 if ((minor = zvol_minor_alloc()) == 0) { 473 dmu_objset_disown(os, zvol_tag); 474 mutex_exit(&zvol_state_lock); 475 return (ENXIO); 476 } 477 478 if (ddi_soft_state_zalloc(zvol_state, minor) != DDI_SUCCESS) { 479 dmu_objset_disown(os, zvol_tag); 480 mutex_exit(&zvol_state_lock); 481 return (EAGAIN); 482 } 483 (void) ddi_prop_update_string(minor, zfs_dip, ZVOL_PROP_NAME, 484 (char *)name); 485 486 (void) snprintf(chrbuf, sizeof (chrbuf), "%u,raw", minor); 487 488 if (ddi_create_minor_node(zfs_dip, chrbuf, S_IFCHR, 489 minor, DDI_PSEUDO, 0) == DDI_FAILURE) { 490 ddi_soft_state_free(zvol_state, minor); 491 dmu_objset_disown(os, zvol_tag); 492 mutex_exit(&zvol_state_lock); 493 return (EAGAIN); 494 } 495 496 (void) snprintf(blkbuf, sizeof (blkbuf), "%u", minor); 497 498 if (ddi_create_minor_node(zfs_dip, blkbuf, S_IFBLK, 499 minor, DDI_PSEUDO, 0) == DDI_FAILURE) { 500 ddi_remove_minor_node(zfs_dip, chrbuf); 501 ddi_soft_state_free(zvol_state, minor); 502 dmu_objset_disown(os, zvol_tag); 503 mutex_exit(&zvol_state_lock); 504 return (EAGAIN); 505 } 506 507 zv = ddi_get_soft_state(zvol_state, minor); 508 509 (void) strlcpy(zv->zv_name, name, MAXPATHLEN); 510 zv->zv_min_bs = DEV_BSHIFT; 511 zv->zv_minor = minor; 512 zv->zv_objset = os; 513 if (dmu_objset_is_snapshot(os)) 514 zv->zv_flags |= ZVOL_RDONLY; 515 mutex_init(&zv->zv_znode.z_range_lock, NULL, MUTEX_DEFAULT, NULL); 516 avl_create(&zv->zv_znode.z_range_avl, zfs_range_compare, 517 sizeof (rl_t), offsetof(rl_t, r_node)); 518 list_create(&zv->zv_extents, sizeof (zvol_extent_t), 519 offsetof(zvol_extent_t, ze_node)); 520 /* get and cache the blocksize */ 521 error = dmu_object_info(os, ZVOL_OBJ, &doi); 522 ASSERT(error == 0); 523 zv->zv_volblocksize = doi.doi_data_block_size; 524 525 zil_replay(os, zv, zvol_replay_vector); 526 dmu_objset_disown(os, zvol_tag); 527 zv->zv_objset = NULL; 528 529 zvol_minors++; 530 531 mutex_exit(&zvol_state_lock); 532 533 return (0); 534 } 535 536 /* 537 * Remove minor node for the specified volume. 538 */ 539 static int 540 zvol_remove_zv(zvol_state_t *zv) 541 { 542 char nmbuf[20]; 543 544 ASSERT(MUTEX_HELD(&zvol_state_lock)); 545 if (zv->zv_total_opens != 0) 546 return (EBUSY); 547 548 (void) snprintf(nmbuf, sizeof (nmbuf), "%u,raw", zv->zv_minor); 549 ddi_remove_minor_node(zfs_dip, nmbuf); 550 551 (void) snprintf(nmbuf, sizeof (nmbuf), "%u", zv->zv_minor); 552 ddi_remove_minor_node(zfs_dip, nmbuf); 553 554 avl_destroy(&zv->zv_znode.z_range_avl); 555 mutex_destroy(&zv->zv_znode.z_range_lock); 556 557 ddi_soft_state_free(zvol_state, zv->zv_minor); 558 559 zvol_minors--; 560 return (0); 561 } 562 563 int 564 zvol_remove_minor(const char *name) 565 { 566 zvol_state_t *zv; 567 int rc; 568 569 mutex_enter(&zvol_state_lock); 570 if ((zv = zvol_minor_lookup(name)) == NULL) { 571 mutex_exit(&zvol_state_lock); 572 return (ENXIO); 573 } 574 rc = zvol_remove_zv(zv); 575 mutex_exit(&zvol_state_lock); 576 return (rc); 577 } 578 579 int 580 zvol_first_open(zvol_state_t *zv) 581 { 582 objset_t *os; 583 uint64_t volsize; 584 int error; 585 uint64_t readonly; 586 587 /* lie and say we're read-only */ 588 error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, B_TRUE, 589 zvol_tag, &os); 590 if (error) 591 return (error); 592 593 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize); 594 if (error) { 595 ASSERT(error == 0); 596 dmu_objset_disown(os, zvol_tag); 597 return (error); 598 } 599 zv->zv_objset = os; 600 zv->zv_volsize = volsize; 601 zv->zv_zilog = zil_open(os, zvol_get_data); 602 zvol_size_changed(zv->zv_volsize, ddi_driver_major(zfs_dip), 603 zv->zv_minor); 604 605 VERIFY(dsl_prop_get_integer(zv->zv_name, "readonly", &readonly, 606 NULL) == 0); 607 if (readonly || dmu_objset_is_snapshot(os)) 608 zv->zv_flags |= ZVOL_RDONLY; 609 else 610 zv->zv_flags &= ~ZVOL_RDONLY; 611 return (error); 612 } 613 614 void 615 zvol_last_close(zvol_state_t *zv) 616 { 617 zil_close(zv->zv_zilog); 618 zv->zv_zilog = NULL; 619 dmu_objset_disown(zv->zv_objset, zvol_tag); 620 zv->zv_objset = NULL; 621 } 622 623 int 624 zvol_prealloc(zvol_state_t *zv) 625 { 626 objset_t *os = zv->zv_objset; 627 dmu_tx_t *tx; 628 uint64_t refd, avail, usedobjs, availobjs; 629 uint64_t resid = zv->zv_volsize; 630 uint64_t off = 0; 631 632 /* Check the space usage before attempting to allocate the space */ 633 dmu_objset_space(os, &refd, &avail, &usedobjs, &availobjs); 634 if (avail < zv->zv_volsize) 635 return (ENOSPC); 636 637 /* Free old extents if they exist */ 638 zvol_free_extents(zv); 639 640 while (resid != 0) { 641 int error; 642 uint64_t bytes = MIN(resid, SPA_MAXBLOCKSIZE); 643 644 tx = dmu_tx_create(os); 645 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes); 646 error = dmu_tx_assign(tx, TXG_WAIT); 647 if (error) { 648 dmu_tx_abort(tx); 649 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, off); 650 return (error); 651 } 652 dmu_prealloc(os, ZVOL_OBJ, off, bytes, tx); 653 dmu_tx_commit(tx); 654 off += bytes; 655 resid -= bytes; 656 } 657 txg_wait_synced(dmu_objset_pool(os), 0); 658 659 return (0); 660 } 661 662 int 663 zvol_update_volsize(objset_t *os, uint64_t volsize) 664 { 665 dmu_tx_t *tx; 666 int error; 667 668 ASSERT(MUTEX_HELD(&zvol_state_lock)); 669 670 tx = dmu_tx_create(os); 671 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 672 error = dmu_tx_assign(tx, TXG_WAIT); 673 if (error) { 674 dmu_tx_abort(tx); 675 return (error); 676 } 677 678 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, 679 &volsize, tx); 680 dmu_tx_commit(tx); 681 682 if (error == 0) 683 error = dmu_free_long_range(os, 684 ZVOL_OBJ, volsize, DMU_OBJECT_END); 685 return (error); 686 } 687 688 void 689 zvol_remove_minors(const char *name) 690 { 691 zvol_state_t *zv; 692 char *namebuf; 693 minor_t minor; 694 695 namebuf = kmem_zalloc(strlen(name) + 2, KM_SLEEP); 696 (void) strncpy(namebuf, name, strlen(name)); 697 (void) strcat(namebuf, "/"); 698 mutex_enter(&zvol_state_lock); 699 for (minor = 1; minor <= ZVOL_MAX_MINOR; minor++) { 700 701 zv = ddi_get_soft_state(zvol_state, minor); 702 if (zv == NULL) 703 continue; 704 if (strncmp(namebuf, zv->zv_name, strlen(namebuf)) == 0) 705 (void) zvol_remove_zv(zv); 706 } 707 kmem_free(namebuf, strlen(name) + 2); 708 709 mutex_exit(&zvol_state_lock); 710 } 711 712 int 713 zvol_set_volsize(const char *name, major_t maj, uint64_t volsize) 714 { 715 zvol_state_t *zv = NULL; 716 objset_t *os; 717 int error; 718 dmu_object_info_t doi; 719 uint64_t old_volsize = 0ULL; 720 uint64_t readonly; 721 722 mutex_enter(&zvol_state_lock); 723 zv = zvol_minor_lookup(name); 724 if ((error = dmu_objset_hold(name, FTAG, &os)) != 0) { 725 mutex_exit(&zvol_state_lock); 726 return (error); 727 } 728 729 if ((error = dmu_object_info(os, ZVOL_OBJ, &doi)) != 0 || 730 (error = zvol_check_volsize(volsize, 731 doi.doi_data_block_size)) != 0) 732 goto out; 733 734 VERIFY(dsl_prop_get_integer(name, "readonly", &readonly, 735 NULL) == 0); 736 if (readonly) { 737 error = EROFS; 738 goto out; 739 } 740 741 error = zvol_update_volsize(os, volsize); 742 /* 743 * Reinitialize the dump area to the new size. If we 744 * failed to resize the dump area then restore it back to 745 * its original size. 746 */ 747 if (zv && error == 0) { 748 if (zv->zv_flags & ZVOL_DUMPIFIED) { 749 old_volsize = zv->zv_volsize; 750 zv->zv_volsize = volsize; 751 if ((error = zvol_dumpify(zv)) != 0 || 752 (error = dumpvp_resize()) != 0) { 753 (void) zvol_update_volsize(os, old_volsize); 754 zv->zv_volsize = old_volsize; 755 error = zvol_dumpify(zv); 756 } 757 } 758 if (error == 0) { 759 zv->zv_volsize = volsize; 760 zvol_size_changed(volsize, maj, zv->zv_minor); 761 } 762 } 763 764 /* 765 * Generate a LUN expansion event. 766 */ 767 if (zv && error == 0) { 768 sysevent_id_t eid; 769 nvlist_t *attr; 770 char *physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 771 772 (void) snprintf(physpath, MAXPATHLEN, "%s%u", ZVOL_PSEUDO_DEV, 773 zv->zv_minor); 774 775 VERIFY(nvlist_alloc(&attr, NV_UNIQUE_NAME, KM_SLEEP) == 0); 776 VERIFY(nvlist_add_string(attr, DEV_PHYS_PATH, physpath) == 0); 777 778 (void) ddi_log_sysevent(zfs_dip, SUNW_VENDOR, EC_DEV_STATUS, 779 ESC_DEV_DLE, attr, &eid, DDI_SLEEP); 780 781 nvlist_free(attr); 782 kmem_free(physpath, MAXPATHLEN); 783 } 784 785 out: 786 dmu_objset_rele(os, FTAG); 787 788 mutex_exit(&zvol_state_lock); 789 790 return (error); 791 } 792 793 /*ARGSUSED*/ 794 int 795 zvol_open(dev_t *devp, int flag, int otyp, cred_t *cr) 796 { 797 minor_t minor = getminor(*devp); 798 zvol_state_t *zv; 799 int err = 0; 800 801 if (minor == 0) /* This is the control device */ 802 return (0); 803 804 mutex_enter(&zvol_state_lock); 805 806 zv = ddi_get_soft_state(zvol_state, minor); 807 if (zv == NULL) { 808 mutex_exit(&zvol_state_lock); 809 return (ENXIO); 810 } 811 812 if (zv->zv_total_opens == 0) 813 err = zvol_first_open(zv); 814 if (err) { 815 mutex_exit(&zvol_state_lock); 816 return (err); 817 } 818 if ((flag & FWRITE) && (zv->zv_flags & ZVOL_RDONLY)) { 819 err = EROFS; 820 goto out; 821 } 822 if (zv->zv_flags & ZVOL_EXCL) { 823 err = EBUSY; 824 goto out; 825 } 826 if (flag & FEXCL) { 827 if (zv->zv_total_opens != 0) { 828 err = EBUSY; 829 goto out; 830 } 831 zv->zv_flags |= ZVOL_EXCL; 832 } 833 834 if (zv->zv_open_count[otyp] == 0 || otyp == OTYP_LYR) { 835 zv->zv_open_count[otyp]++; 836 zv->zv_total_opens++; 837 } 838 mutex_exit(&zvol_state_lock); 839 840 return (err); 841 out: 842 if (zv->zv_total_opens == 0) 843 zvol_last_close(zv); 844 mutex_exit(&zvol_state_lock); 845 return (err); 846 } 847 848 /*ARGSUSED*/ 849 int 850 zvol_close(dev_t dev, int flag, int otyp, cred_t *cr) 851 { 852 minor_t minor = getminor(dev); 853 zvol_state_t *zv; 854 int error = 0; 855 856 if (minor == 0) /* This is the control device */ 857 return (0); 858 859 mutex_enter(&zvol_state_lock); 860 861 zv = ddi_get_soft_state(zvol_state, minor); 862 if (zv == NULL) { 863 mutex_exit(&zvol_state_lock); 864 return (ENXIO); 865 } 866 867 if (zv->zv_flags & ZVOL_EXCL) { 868 ASSERT(zv->zv_total_opens == 1); 869 zv->zv_flags &= ~ZVOL_EXCL; 870 } 871 872 /* 873 * If the open count is zero, this is a spurious close. 874 * That indicates a bug in the kernel / DDI framework. 875 */ 876 ASSERT(zv->zv_open_count[otyp] != 0); 877 ASSERT(zv->zv_total_opens != 0); 878 879 /* 880 * You may get multiple opens, but only one close. 881 */ 882 zv->zv_open_count[otyp]--; 883 zv->zv_total_opens--; 884 885 if (zv->zv_total_opens == 0) 886 zvol_last_close(zv); 887 888 mutex_exit(&zvol_state_lock); 889 return (error); 890 } 891 892 static void 893 zvol_get_done(zgd_t *zgd, int error) 894 { 895 if (zgd->zgd_db) 896 dmu_buf_rele(zgd->zgd_db, zgd); 897 898 zfs_range_unlock(zgd->zgd_rl); 899 900 if (error == 0 && zgd->zgd_bp) 901 zil_add_block(zgd->zgd_zilog, zgd->zgd_bp); 902 903 kmem_free(zgd, sizeof (zgd_t)); 904 } 905 906 /* 907 * Get data to generate a TX_WRITE intent log record. 908 */ 909 static int 910 zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio) 911 { 912 zvol_state_t *zv = arg; 913 objset_t *os = zv->zv_objset; 914 uint64_t object = ZVOL_OBJ; 915 uint64_t offset = lr->lr_offset; 916 uint64_t size = lr->lr_length; /* length of user data */ 917 blkptr_t *bp = &lr->lr_blkptr; 918 dmu_buf_t *db; 919 zgd_t *zgd; 920 int error; 921 922 ASSERT(zio != NULL); 923 ASSERT(size != 0); 924 925 zgd = kmem_zalloc(sizeof (zgd_t), KM_SLEEP); 926 zgd->zgd_zilog = zv->zv_zilog; 927 zgd->zgd_rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER); 928 929 /* 930 * Write records come in two flavors: immediate and indirect. 931 * For small writes it's cheaper to store the data with the 932 * log record (immediate); for large writes it's cheaper to 933 * sync the data and get a pointer to it (indirect) so that 934 * we don't have to write the data twice. 935 */ 936 if (buf != NULL) { /* immediate write */ 937 error = dmu_read(os, object, offset, size, buf, 938 DMU_READ_NO_PREFETCH); 939 } else { 940 size = zv->zv_volblocksize; 941 offset = P2ALIGN(offset, size); 942 error = dmu_buf_hold(os, object, offset, zgd, &db); 943 if (error == 0) { 944 zgd->zgd_db = db; 945 zgd->zgd_bp = bp; 946 947 ASSERT(db->db_offset == offset); 948 ASSERT(db->db_size == size); 949 950 error = dmu_sync(zio, lr->lr_common.lrc_txg, 951 zvol_get_done, zgd); 952 953 if (error == 0) 954 return (0); 955 } 956 } 957 958 zvol_get_done(zgd, error); 959 960 return (error); 961 } 962 963 /* 964 * zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions. 965 * 966 * We store data in the log buffers if it's small enough. 967 * Otherwise we will later flush the data out via dmu_sync(). 968 */ 969 ssize_t zvol_immediate_write_sz = 32768; 970 971 static void 972 zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, offset_t off, ssize_t resid, 973 boolean_t sync) 974 { 975 uint32_t blocksize = zv->zv_volblocksize; 976 zilog_t *zilog = zv->zv_zilog; 977 boolean_t slogging; 978 ssize_t immediate_write_sz; 979 980 if (zil_disable) 981 return; 982 983 if (zil_replaying(zilog, tx)) 984 return; 985 986 immediate_write_sz = (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT) 987 ? 0 : zvol_immediate_write_sz; 988 989 slogging = spa_has_slogs(zilog->zl_spa) && 990 (zilog->zl_logbias == ZFS_LOGBIAS_LATENCY); 991 992 while (resid) { 993 itx_t *itx; 994 lr_write_t *lr; 995 ssize_t len; 996 itx_wr_state_t write_state; 997 998 /* 999 * Unlike zfs_log_write() we can be called with 1000 * upto DMU_MAX_ACCESS/2 (5MB) writes. 1001 */ 1002 if (blocksize > immediate_write_sz && !slogging && 1003 resid >= blocksize && off % blocksize == 0) { 1004 write_state = WR_INDIRECT; /* uses dmu_sync */ 1005 len = blocksize; 1006 } else if (sync) { 1007 write_state = WR_COPIED; 1008 len = MIN(ZIL_MAX_LOG_DATA, resid); 1009 } else { 1010 write_state = WR_NEED_COPY; 1011 len = MIN(ZIL_MAX_LOG_DATA, resid); 1012 } 1013 1014 itx = zil_itx_create(TX_WRITE, sizeof (*lr) + 1015 (write_state == WR_COPIED ? len : 0)); 1016 lr = (lr_write_t *)&itx->itx_lr; 1017 if (write_state == WR_COPIED && dmu_read(zv->zv_objset, 1018 ZVOL_OBJ, off, len, lr + 1, DMU_READ_NO_PREFETCH) != 0) { 1019 zil_itx_destroy(itx); 1020 itx = zil_itx_create(TX_WRITE, sizeof (*lr)); 1021 lr = (lr_write_t *)&itx->itx_lr; 1022 write_state = WR_NEED_COPY; 1023 } 1024 1025 itx->itx_wr_state = write_state; 1026 if (write_state == WR_NEED_COPY) 1027 itx->itx_sod += len; 1028 lr->lr_foid = ZVOL_OBJ; 1029 lr->lr_offset = off; 1030 lr->lr_length = len; 1031 lr->lr_blkoff = 0; 1032 BP_ZERO(&lr->lr_blkptr); 1033 1034 itx->itx_private = zv; 1035 itx->itx_sync = sync; 1036 1037 (void) zil_itx_assign(zilog, itx, tx); 1038 1039 off += len; 1040 resid -= len; 1041 } 1042 } 1043 1044 static int 1045 zvol_dumpio_vdev(vdev_t *vd, void *addr, uint64_t offset, uint64_t size, 1046 boolean_t doread, boolean_t isdump) 1047 { 1048 vdev_disk_t *dvd; 1049 int c; 1050 int numerrors = 0; 1051 1052 for (c = 0; c < vd->vdev_children; c++) { 1053 ASSERT(vd->vdev_ops == &vdev_mirror_ops || 1054 vd->vdev_ops == &vdev_replacing_ops || 1055 vd->vdev_ops == &vdev_spare_ops); 1056 int err = zvol_dumpio_vdev(vd->vdev_child[c], 1057 addr, offset, size, doread, isdump); 1058 if (err != 0) { 1059 numerrors++; 1060 } else if (doread) { 1061 break; 1062 } 1063 } 1064 1065 if (!vd->vdev_ops->vdev_op_leaf) 1066 return (numerrors < vd->vdev_children ? 0 : EIO); 1067 1068 if (doread && !vdev_readable(vd)) 1069 return (EIO); 1070 else if (!doread && !vdev_writeable(vd)) 1071 return (EIO); 1072 1073 dvd = vd->vdev_tsd; 1074 ASSERT3P(dvd, !=, NULL); 1075 offset += VDEV_LABEL_START_SIZE; 1076 1077 if (ddi_in_panic() || isdump) { 1078 ASSERT(!doread); 1079 if (doread) 1080 return (EIO); 1081 return (ldi_dump(dvd->vd_lh, addr, lbtodb(offset), 1082 lbtodb(size))); 1083 } else { 1084 return (vdev_disk_physio(dvd->vd_lh, addr, size, offset, 1085 doread ? B_READ : B_WRITE)); 1086 } 1087 } 1088 1089 static int 1090 zvol_dumpio(zvol_state_t *zv, void *addr, uint64_t offset, uint64_t size, 1091 boolean_t doread, boolean_t isdump) 1092 { 1093 vdev_t *vd; 1094 int error; 1095 zvol_extent_t *ze; 1096 spa_t *spa = dmu_objset_spa(zv->zv_objset); 1097 1098 /* Must be sector aligned, and not stradle a block boundary. */ 1099 if (P2PHASE(offset, DEV_BSIZE) || P2PHASE(size, DEV_BSIZE) || 1100 P2BOUNDARY(offset, size, zv->zv_volblocksize)) { 1101 return (EINVAL); 1102 } 1103 ASSERT(size <= zv->zv_volblocksize); 1104 1105 /* Locate the extent this belongs to */ 1106 ze = list_head(&zv->zv_extents); 1107 while (offset >= ze->ze_nblks * zv->zv_volblocksize) { 1108 offset -= ze->ze_nblks * zv->zv_volblocksize; 1109 ze = list_next(&zv->zv_extents, ze); 1110 } 1111 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER); 1112 vd = vdev_lookup_top(spa, DVA_GET_VDEV(&ze->ze_dva)); 1113 offset += DVA_GET_OFFSET(&ze->ze_dva); 1114 error = zvol_dumpio_vdev(vd, addr, offset, size, doread, isdump); 1115 spa_config_exit(spa, SCL_STATE, FTAG); 1116 return (error); 1117 } 1118 1119 int 1120 zvol_strategy(buf_t *bp) 1121 { 1122 zvol_state_t *zv = ddi_get_soft_state(zvol_state, getminor(bp->b_edev)); 1123 uint64_t off, volsize; 1124 size_t resid; 1125 char *addr; 1126 objset_t *os; 1127 rl_t *rl; 1128 int error = 0; 1129 boolean_t doread = bp->b_flags & B_READ; 1130 boolean_t is_dump = zv->zv_flags & ZVOL_DUMPIFIED; 1131 boolean_t sync; 1132 1133 if (zv == NULL) { 1134 bioerror(bp, ENXIO); 1135 biodone(bp); 1136 return (0); 1137 } 1138 1139 if (getminor(bp->b_edev) == 0) { 1140 bioerror(bp, EINVAL); 1141 biodone(bp); 1142 return (0); 1143 } 1144 1145 if (!(bp->b_flags & B_READ) && (zv->zv_flags & ZVOL_RDONLY)) { 1146 bioerror(bp, EROFS); 1147 biodone(bp); 1148 return (0); 1149 } 1150 1151 off = ldbtob(bp->b_blkno); 1152 volsize = zv->zv_volsize; 1153 1154 os = zv->zv_objset; 1155 ASSERT(os != NULL); 1156 1157 bp_mapin(bp); 1158 addr = bp->b_un.b_addr; 1159 resid = bp->b_bcount; 1160 1161 if (resid > 0 && (off < 0 || off >= volsize)) { 1162 bioerror(bp, EIO); 1163 biodone(bp); 1164 return (0); 1165 } 1166 1167 sync = !(bp->b_flags & B_ASYNC) && !doread && !is_dump && 1168 !(zv->zv_flags & ZVOL_WCE) && !zil_disable; 1169 1170 /* 1171 * There must be no buffer changes when doing a dmu_sync() because 1172 * we can't change the data whilst calculating the checksum. 1173 */ 1174 rl = zfs_range_lock(&zv->zv_znode, off, resid, 1175 doread ? RL_READER : RL_WRITER); 1176 1177 while (resid != 0 && off < volsize) { 1178 size_t size = MIN(resid, zvol_maxphys); 1179 if (is_dump) { 1180 size = MIN(size, P2END(off, zv->zv_volblocksize) - off); 1181 error = zvol_dumpio(zv, addr, off, size, 1182 doread, B_FALSE); 1183 } else if (doread) { 1184 error = dmu_read(os, ZVOL_OBJ, off, size, addr, 1185 DMU_READ_PREFETCH); 1186 } else { 1187 dmu_tx_t *tx = dmu_tx_create(os); 1188 dmu_tx_hold_write(tx, ZVOL_OBJ, off, size); 1189 error = dmu_tx_assign(tx, TXG_WAIT); 1190 if (error) { 1191 dmu_tx_abort(tx); 1192 } else { 1193 dmu_write(os, ZVOL_OBJ, off, size, addr, tx); 1194 zvol_log_write(zv, tx, off, size, sync); 1195 dmu_tx_commit(tx); 1196 } 1197 } 1198 if (error) { 1199 /* convert checksum errors into IO errors */ 1200 if (error == ECKSUM) 1201 error = EIO; 1202 break; 1203 } 1204 off += size; 1205 addr += size; 1206 resid -= size; 1207 } 1208 zfs_range_unlock(rl); 1209 1210 if ((bp->b_resid = resid) == bp->b_bcount) 1211 bioerror(bp, off > volsize ? EINVAL : error); 1212 1213 if (sync) 1214 zil_commit(zv->zv_zilog, UINT64_MAX, ZVOL_OBJ); 1215 biodone(bp); 1216 1217 return (0); 1218 } 1219 1220 /* 1221 * Set the buffer count to the zvol maximum transfer. 1222 * Using our own routine instead of the default minphys() 1223 * means that for larger writes we write bigger buffers on X86 1224 * (128K instead of 56K) and flush the disk write cache less often 1225 * (every zvol_maxphys - currently 1MB) instead of minphys (currently 1226 * 56K on X86 and 128K on sparc). 1227 */ 1228 void 1229 zvol_minphys(struct buf *bp) 1230 { 1231 if (bp->b_bcount > zvol_maxphys) 1232 bp->b_bcount = zvol_maxphys; 1233 } 1234 1235 int 1236 zvol_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblocks) 1237 { 1238 minor_t minor = getminor(dev); 1239 zvol_state_t *zv; 1240 int error = 0; 1241 uint64_t size; 1242 uint64_t boff; 1243 uint64_t resid; 1244 1245 if (minor == 0) /* This is the control device */ 1246 return (ENXIO); 1247 1248 zv = ddi_get_soft_state(zvol_state, minor); 1249 if (zv == NULL) 1250 return (ENXIO); 1251 1252 boff = ldbtob(blkno); 1253 resid = ldbtob(nblocks); 1254 1255 VERIFY3U(boff + resid, <=, zv->zv_volsize); 1256 1257 while (resid) { 1258 size = MIN(resid, P2END(boff, zv->zv_volblocksize) - boff); 1259 error = zvol_dumpio(zv, addr, boff, size, B_FALSE, B_TRUE); 1260 if (error) 1261 break; 1262 boff += size; 1263 addr += size; 1264 resid -= size; 1265 } 1266 1267 return (error); 1268 } 1269 1270 /*ARGSUSED*/ 1271 int 1272 zvol_read(dev_t dev, uio_t *uio, cred_t *cr) 1273 { 1274 minor_t minor = getminor(dev); 1275 zvol_state_t *zv; 1276 uint64_t volsize; 1277 rl_t *rl; 1278 int error = 0; 1279 1280 if (minor == 0) /* This is the control device */ 1281 return (ENXIO); 1282 1283 zv = ddi_get_soft_state(zvol_state, minor); 1284 if (zv == NULL) 1285 return (ENXIO); 1286 1287 volsize = zv->zv_volsize; 1288 if (uio->uio_resid > 0 && 1289 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize)) 1290 return (EIO); 1291 1292 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1293 error = physio(zvol_strategy, NULL, dev, B_READ, 1294 zvol_minphys, uio); 1295 return (error); 1296 } 1297 1298 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid, 1299 RL_READER); 1300 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1301 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1302 1303 /* don't read past the end */ 1304 if (bytes > volsize - uio->uio_loffset) 1305 bytes = volsize - uio->uio_loffset; 1306 1307 error = dmu_read_uio(zv->zv_objset, ZVOL_OBJ, uio, bytes); 1308 if (error) { 1309 /* convert checksum errors into IO errors */ 1310 if (error == ECKSUM) 1311 error = EIO; 1312 break; 1313 } 1314 } 1315 zfs_range_unlock(rl); 1316 return (error); 1317 } 1318 1319 /*ARGSUSED*/ 1320 int 1321 zvol_write(dev_t dev, uio_t *uio, cred_t *cr) 1322 { 1323 minor_t minor = getminor(dev); 1324 zvol_state_t *zv; 1325 uint64_t volsize; 1326 rl_t *rl; 1327 int error = 0; 1328 boolean_t sync; 1329 1330 if (minor == 0) /* This is the control device */ 1331 return (ENXIO); 1332 1333 zv = ddi_get_soft_state(zvol_state, minor); 1334 if (zv == NULL) 1335 return (ENXIO); 1336 1337 volsize = zv->zv_volsize; 1338 if (uio->uio_resid > 0 && 1339 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize)) 1340 return (EIO); 1341 1342 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1343 error = physio(zvol_strategy, NULL, dev, B_WRITE, 1344 zvol_minphys, uio); 1345 return (error); 1346 } 1347 1348 sync = !(zv->zv_flags & ZVOL_WCE) && !zil_disable; 1349 1350 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid, 1351 RL_WRITER); 1352 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1353 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1354 uint64_t off = uio->uio_loffset; 1355 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset); 1356 1357 if (bytes > volsize - off) /* don't write past the end */ 1358 bytes = volsize - off; 1359 1360 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes); 1361 error = dmu_tx_assign(tx, TXG_WAIT); 1362 if (error) { 1363 dmu_tx_abort(tx); 1364 break; 1365 } 1366 error = dmu_write_uio(zv->zv_objset, ZVOL_OBJ, uio, bytes, tx); 1367 if (error == 0) 1368 zvol_log_write(zv, tx, off, bytes, sync); 1369 dmu_tx_commit(tx); 1370 1371 if (error) 1372 break; 1373 } 1374 zfs_range_unlock(rl); 1375 if (sync) 1376 zil_commit(zv->zv_zilog, UINT64_MAX, ZVOL_OBJ); 1377 return (error); 1378 } 1379 1380 int 1381 zvol_getefi(void *arg, int flag, uint64_t vs, uint8_t bs) 1382 { 1383 struct uuid uuid = EFI_RESERVED; 1384 efi_gpe_t gpe = { 0 }; 1385 uint32_t crc; 1386 dk_efi_t efi; 1387 int length; 1388 char *ptr; 1389 1390 if (ddi_copyin(arg, &efi, sizeof (dk_efi_t), flag)) 1391 return (EFAULT); 1392 ptr = (char *)(uintptr_t)efi.dki_data_64; 1393 length = efi.dki_length; 1394 /* 1395 * Some clients may attempt to request a PMBR for the 1396 * zvol. Currently this interface will return EINVAL to 1397 * such requests. These requests could be supported by 1398 * adding a check for lba == 0 and consing up an appropriate 1399 * PMBR. 1400 */ 1401 if (efi.dki_lba < 1 || efi.dki_lba > 2 || length <= 0) 1402 return (EINVAL); 1403 1404 gpe.efi_gpe_StartingLBA = LE_64(34ULL); 1405 gpe.efi_gpe_EndingLBA = LE_64((vs >> bs) - 1); 1406 UUID_LE_CONVERT(gpe.efi_gpe_PartitionTypeGUID, uuid); 1407 1408 if (efi.dki_lba == 1) { 1409 efi_gpt_t gpt = { 0 }; 1410 1411 gpt.efi_gpt_Signature = LE_64(EFI_SIGNATURE); 1412 gpt.efi_gpt_Revision = LE_32(EFI_VERSION_CURRENT); 1413 gpt.efi_gpt_HeaderSize = LE_32(sizeof (gpt)); 1414 gpt.efi_gpt_MyLBA = LE_64(1ULL); 1415 gpt.efi_gpt_FirstUsableLBA = LE_64(34ULL); 1416 gpt.efi_gpt_LastUsableLBA = LE_64((vs >> bs) - 1); 1417 gpt.efi_gpt_PartitionEntryLBA = LE_64(2ULL); 1418 gpt.efi_gpt_NumberOfPartitionEntries = LE_32(1); 1419 gpt.efi_gpt_SizeOfPartitionEntry = 1420 LE_32(sizeof (efi_gpe_t)); 1421 CRC32(crc, &gpe, sizeof (gpe), -1U, crc32_table); 1422 gpt.efi_gpt_PartitionEntryArrayCRC32 = LE_32(~crc); 1423 CRC32(crc, &gpt, sizeof (gpt), -1U, crc32_table); 1424 gpt.efi_gpt_HeaderCRC32 = LE_32(~crc); 1425 if (ddi_copyout(&gpt, ptr, MIN(sizeof (gpt), length), 1426 flag)) 1427 return (EFAULT); 1428 ptr += sizeof (gpt); 1429 length -= sizeof (gpt); 1430 } 1431 if (length > 0 && ddi_copyout(&gpe, ptr, MIN(sizeof (gpe), 1432 length), flag)) 1433 return (EFAULT); 1434 return (0); 1435 } 1436 1437 /* 1438 * Dirtbag ioctls to support mkfs(1M) for UFS filesystems. See dkio(7I). 1439 */ 1440 /*ARGSUSED*/ 1441 int 1442 zvol_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp) 1443 { 1444 zvol_state_t *zv; 1445 struct dk_cinfo dki; 1446 struct dk_minfo dkm; 1447 struct dk_callback *dkc; 1448 int error = 0; 1449 rl_t *rl; 1450 1451 mutex_enter(&zvol_state_lock); 1452 1453 zv = ddi_get_soft_state(zvol_state, getminor(dev)); 1454 1455 if (zv == NULL) { 1456 mutex_exit(&zvol_state_lock); 1457 return (ENXIO); 1458 } 1459 ASSERT(zv->zv_total_opens > 0); 1460 1461 switch (cmd) { 1462 1463 case DKIOCINFO: 1464 bzero(&dki, sizeof (dki)); 1465 (void) strcpy(dki.dki_cname, "zvol"); 1466 (void) strcpy(dki.dki_dname, "zvol"); 1467 dki.dki_ctype = DKC_UNKNOWN; 1468 dki.dki_maxtransfer = 1 << (SPA_MAXBLOCKSHIFT - zv->zv_min_bs); 1469 mutex_exit(&zvol_state_lock); 1470 if (ddi_copyout(&dki, (void *)arg, sizeof (dki), flag)) 1471 error = EFAULT; 1472 return (error); 1473 1474 case DKIOCGMEDIAINFO: 1475 bzero(&dkm, sizeof (dkm)); 1476 dkm.dki_lbsize = 1U << zv->zv_min_bs; 1477 dkm.dki_capacity = zv->zv_volsize >> zv->zv_min_bs; 1478 dkm.dki_media_type = DK_UNKNOWN; 1479 mutex_exit(&zvol_state_lock); 1480 if (ddi_copyout(&dkm, (void *)arg, sizeof (dkm), flag)) 1481 error = EFAULT; 1482 return (error); 1483 1484 case DKIOCGETEFI: 1485 { 1486 uint64_t vs = zv->zv_volsize; 1487 uint8_t bs = zv->zv_min_bs; 1488 1489 mutex_exit(&zvol_state_lock); 1490 error = zvol_getefi((void *)arg, flag, vs, bs); 1491 return (error); 1492 } 1493 1494 case DKIOCFLUSHWRITECACHE: 1495 dkc = (struct dk_callback *)arg; 1496 mutex_exit(&zvol_state_lock); 1497 zil_commit(zv->zv_zilog, UINT64_MAX, ZVOL_OBJ); 1498 if ((flag & FKIOCTL) && dkc != NULL && dkc->dkc_callback) { 1499 (*dkc->dkc_callback)(dkc->dkc_cookie, error); 1500 error = 0; 1501 } 1502 return (error); 1503 1504 case DKIOCGETWCE: 1505 { 1506 int wce = (zv->zv_flags & ZVOL_WCE) ? 1 : 0; 1507 if (ddi_copyout(&wce, (void *)arg, sizeof (int), 1508 flag)) 1509 error = EFAULT; 1510 break; 1511 } 1512 case DKIOCSETWCE: 1513 { 1514 int wce; 1515 if (ddi_copyin((void *)arg, &wce, sizeof (int), 1516 flag)) { 1517 error = EFAULT; 1518 break; 1519 } 1520 if (wce) { 1521 zv->zv_flags |= ZVOL_WCE; 1522 mutex_exit(&zvol_state_lock); 1523 } else { 1524 zv->zv_flags &= ~ZVOL_WCE; 1525 mutex_exit(&zvol_state_lock); 1526 zil_commit(zv->zv_zilog, UINT64_MAX, ZVOL_OBJ); 1527 } 1528 return (0); 1529 } 1530 1531 case DKIOCGGEOM: 1532 case DKIOCGVTOC: 1533 /* 1534 * commands using these (like prtvtoc) expect ENOTSUP 1535 * since we're emulating an EFI label 1536 */ 1537 error = ENOTSUP; 1538 break; 1539 1540 case DKIOCDUMPINIT: 1541 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize, 1542 RL_WRITER); 1543 error = zvol_dumpify(zv); 1544 zfs_range_unlock(rl); 1545 break; 1546 1547 case DKIOCDUMPFINI: 1548 if (!(zv->zv_flags & ZVOL_DUMPIFIED)) 1549 break; 1550 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize, 1551 RL_WRITER); 1552 error = zvol_dump_fini(zv); 1553 zfs_range_unlock(rl); 1554 break; 1555 1556 default: 1557 error = ENOTTY; 1558 break; 1559 1560 } 1561 mutex_exit(&zvol_state_lock); 1562 return (error); 1563 } 1564 1565 int 1566 zvol_busy(void) 1567 { 1568 return (zvol_minors != 0); 1569 } 1570 1571 void 1572 zvol_init(void) 1573 { 1574 VERIFY(ddi_soft_state_init(&zvol_state, sizeof (zvol_state_t), 1) == 0); 1575 mutex_init(&zvol_state_lock, NULL, MUTEX_DEFAULT, NULL); 1576 } 1577 1578 void 1579 zvol_fini(void) 1580 { 1581 mutex_destroy(&zvol_state_lock); 1582 ddi_soft_state_fini(&zvol_state); 1583 } 1584 1585 static int 1586 zvol_dump_init(zvol_state_t *zv, boolean_t resize) 1587 { 1588 dmu_tx_t *tx; 1589 int error = 0; 1590 objset_t *os = zv->zv_objset; 1591 nvlist_t *nv = NULL; 1592 1593 ASSERT(MUTEX_HELD(&zvol_state_lock)); 1594 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 0, 1595 DMU_OBJECT_END); 1596 /* wait for dmu_free_long_range to actually free the blocks */ 1597 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 1598 1599 tx = dmu_tx_create(os); 1600 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 1601 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 1602 error = dmu_tx_assign(tx, TXG_WAIT); 1603 if (error) { 1604 dmu_tx_abort(tx); 1605 return (error); 1606 } 1607 1608 /* 1609 * If we are resizing the dump device then we only need to 1610 * update the refreservation to match the newly updated 1611 * zvolsize. Otherwise, we save off the original state of the 1612 * zvol so that we can restore them if the zvol is ever undumpified. 1613 */ 1614 if (resize) { 1615 error = zap_update(os, ZVOL_ZAP_OBJ, 1616 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 1617 &zv->zv_volsize, tx); 1618 } else { 1619 uint64_t checksum, compress, refresrv, vbs; 1620 1621 error = dsl_prop_get_integer(zv->zv_name, 1622 zfs_prop_to_name(ZFS_PROP_COMPRESSION), &compress, NULL); 1623 error = error ? error : dsl_prop_get_integer(zv->zv_name, 1624 zfs_prop_to_name(ZFS_PROP_CHECKSUM), &checksum, NULL); 1625 error = error ? error : dsl_prop_get_integer(zv->zv_name, 1626 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &refresrv, NULL); 1627 error = error ? error : dsl_prop_get_integer(zv->zv_name, 1628 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &vbs, NULL); 1629 1630 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1631 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, 1632 &compress, tx); 1633 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1634 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum, tx); 1635 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1636 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 1637 &refresrv, tx); 1638 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1639 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, 1640 &vbs, tx); 1641 error = error ? error : dmu_object_set_blocksize( 1642 os, ZVOL_OBJ, SPA_MAXBLOCKSIZE, 0, tx); 1643 if (error == 0) 1644 zv->zv_volblocksize = SPA_MAXBLOCKSIZE; 1645 } 1646 dmu_tx_commit(tx); 1647 1648 /* 1649 * We only need update the zvol's property if we are initializing 1650 * the dump area for the first time. 1651 */ 1652 if (!resize) { 1653 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 1654 VERIFY(nvlist_add_uint64(nv, 1655 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 0) == 0); 1656 VERIFY(nvlist_add_uint64(nv, 1657 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 1658 ZIO_COMPRESS_OFF) == 0); 1659 VERIFY(nvlist_add_uint64(nv, 1660 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 1661 ZIO_CHECKSUM_OFF) == 0); 1662 1663 error = zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL, 1664 nv, NULL); 1665 nvlist_free(nv); 1666 1667 if (error) 1668 return (error); 1669 } 1670 1671 /* Allocate the space for the dump */ 1672 error = zvol_prealloc(zv); 1673 return (error); 1674 } 1675 1676 static int 1677 zvol_dumpify(zvol_state_t *zv) 1678 { 1679 int error = 0; 1680 uint64_t dumpsize = 0; 1681 dmu_tx_t *tx; 1682 objset_t *os = zv->zv_objset; 1683 1684 if (zv->zv_flags & ZVOL_RDONLY) 1685 return (EROFS); 1686 1687 if (zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 1688 8, 1, &dumpsize) != 0 || dumpsize != zv->zv_volsize) { 1689 boolean_t resize = (dumpsize > 0) ? B_TRUE : B_FALSE; 1690 1691 if ((error = zvol_dump_init(zv, resize)) != 0) { 1692 (void) zvol_dump_fini(zv); 1693 return (error); 1694 } 1695 } 1696 1697 /* 1698 * Build up our lba mapping. 1699 */ 1700 error = zvol_get_lbas(zv); 1701 if (error) { 1702 (void) zvol_dump_fini(zv); 1703 return (error); 1704 } 1705 1706 tx = dmu_tx_create(os); 1707 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 1708 error = dmu_tx_assign(tx, TXG_WAIT); 1709 if (error) { 1710 dmu_tx_abort(tx); 1711 (void) zvol_dump_fini(zv); 1712 return (error); 1713 } 1714 1715 zv->zv_flags |= ZVOL_DUMPIFIED; 1716 error = zap_update(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 8, 1, 1717 &zv->zv_volsize, tx); 1718 dmu_tx_commit(tx); 1719 1720 if (error) { 1721 (void) zvol_dump_fini(zv); 1722 return (error); 1723 } 1724 1725 txg_wait_synced(dmu_objset_pool(os), 0); 1726 return (0); 1727 } 1728 1729 static int 1730 zvol_dump_fini(zvol_state_t *zv) 1731 { 1732 dmu_tx_t *tx; 1733 objset_t *os = zv->zv_objset; 1734 nvlist_t *nv; 1735 int error = 0; 1736 uint64_t checksum, compress, refresrv, vbs; 1737 1738 /* 1739 * Attempt to restore the zvol back to its pre-dumpified state. 1740 * This is a best-effort attempt as it's possible that not all 1741 * of these properties were initialized during the dumpify process 1742 * (i.e. error during zvol_dump_init). 1743 */ 1744 1745 tx = dmu_tx_create(os); 1746 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 1747 error = dmu_tx_assign(tx, TXG_WAIT); 1748 if (error) { 1749 dmu_tx_abort(tx); 1750 return (error); 1751 } 1752 (void) zap_remove(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, tx); 1753 dmu_tx_commit(tx); 1754 1755 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 1756 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum); 1757 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 1758 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, &compress); 1759 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 1760 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, &refresrv); 1761 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 1762 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, &vbs); 1763 1764 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 1765 (void) nvlist_add_uint64(nv, 1766 zfs_prop_to_name(ZFS_PROP_CHECKSUM), checksum); 1767 (void) nvlist_add_uint64(nv, 1768 zfs_prop_to_name(ZFS_PROP_COMPRESSION), compress); 1769 (void) nvlist_add_uint64(nv, 1770 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), refresrv); 1771 (void) zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL, 1772 nv, NULL); 1773 nvlist_free(nv); 1774 1775 zvol_free_extents(zv); 1776 zv->zv_flags &= ~ZVOL_DUMPIFIED; 1777 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, DMU_OBJECT_END); 1778 /* wait for dmu_free_long_range to actually free the blocks */ 1779 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 1780 tx = dmu_tx_create(os); 1781 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 1782 error = dmu_tx_assign(tx, TXG_WAIT); 1783 if (error) { 1784 dmu_tx_abort(tx); 1785 return (error); 1786 } 1787 if (dmu_object_set_blocksize(os, ZVOL_OBJ, vbs, 0, tx) == 0) 1788 zv->zv_volblocksize = vbs; 1789 dmu_tx_commit(tx); 1790 1791 return (0); 1792 } 1793