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 2008 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 ZFS-specific devfsadm link generator. 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 79 #include "zfs_namecheck.h" 80 81 static void *zvol_state; 82 83 #define ZVOL_DUMPSIZE "dumpsize" 84 85 /* 86 * This lock protects the zvol_state structure from being modified 87 * while it's being used, e.g. an open that comes in before a create 88 * finishes. It also protects temporary opens of the dataset so that, 89 * e.g., an open doesn't get a spurious EBUSY. 90 */ 91 static kmutex_t zvol_state_lock; 92 static uint32_t zvol_minors; 93 94 typedef struct zvol_extent { 95 list_node_t ze_node; 96 dva_t ze_dva; /* dva associated with this extent */ 97 uint64_t ze_nblks; /* number of blocks in extent */ 98 } zvol_extent_t; 99 100 /* 101 * The in-core state of each volume. 102 */ 103 typedef struct zvol_state { 104 char zv_name[MAXPATHLEN]; /* pool/dd name */ 105 uint64_t zv_volsize; /* amount of space we advertise */ 106 uint64_t zv_volblocksize; /* volume block size */ 107 minor_t zv_minor; /* minor number */ 108 uint8_t zv_min_bs; /* minimum addressable block shift */ 109 uint8_t zv_flags; /* readonly; dumpified */ 110 objset_t *zv_objset; /* objset handle */ 111 uint32_t zv_mode; /* DS_MODE_* flags at open time */ 112 uint32_t zv_open_count[OTYPCNT]; /* open counts */ 113 uint32_t zv_total_opens; /* total open count */ 114 zilog_t *zv_zilog; /* ZIL handle */ 115 list_t zv_extents; /* List of extents for dump */ 116 uint64_t zv_txg_assign; /* txg to assign during ZIL replay */ 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 126 127 /* 128 * zvol maximum transfer in one DMU tx. 129 */ 130 int zvol_maxphys = DMU_MAX_ACCESS/2; 131 132 extern int zfs_set_prop_nvlist(const char *, nvlist_t *); 133 static int zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio); 134 static int zvol_dumpify(zvol_state_t *zv); 135 static int zvol_dump_fini(zvol_state_t *zv); 136 static int zvol_dump_init(zvol_state_t *zv, boolean_t resize); 137 138 static void 139 zvol_size_changed(zvol_state_t *zv, major_t maj) 140 { 141 dev_t dev = makedevice(maj, zv->zv_minor); 142 143 VERIFY(ddi_prop_update_int64(dev, zfs_dip, 144 "Size", zv->zv_volsize) == DDI_SUCCESS); 145 VERIFY(ddi_prop_update_int64(dev, zfs_dip, 146 "Nblocks", lbtodb(zv->zv_volsize)) == DDI_SUCCESS); 147 148 /* Notify specfs to invalidate the cached size */ 149 spec_size_invalidate(dev, VBLK); 150 spec_size_invalidate(dev, VCHR); 151 } 152 153 int 154 zvol_check_volsize(uint64_t volsize, uint64_t blocksize) 155 { 156 if (volsize == 0) 157 return (EINVAL); 158 159 if (volsize % blocksize != 0) 160 return (EINVAL); 161 162 #ifdef _ILP32 163 if (volsize - 1 > SPEC_MAXOFFSET_T) 164 return (EOVERFLOW); 165 #endif 166 return (0); 167 } 168 169 int 170 zvol_check_volblocksize(uint64_t volblocksize) 171 { 172 if (volblocksize < SPA_MINBLOCKSIZE || 173 volblocksize > SPA_MAXBLOCKSIZE || 174 !ISP2(volblocksize)) 175 return (EDOM); 176 177 return (0); 178 } 179 180 static void 181 zvol_readonly_changed_cb(void *arg, uint64_t newval) 182 { 183 zvol_state_t *zv = arg; 184 185 if (newval) 186 zv->zv_flags |= ZVOL_RDONLY; 187 else 188 zv->zv_flags &= ~ZVOL_RDONLY; 189 } 190 191 int 192 zvol_get_stats(objset_t *os, nvlist_t *nv) 193 { 194 int error; 195 dmu_object_info_t doi; 196 uint64_t val; 197 198 199 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val); 200 if (error) 201 return (error); 202 203 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val); 204 205 error = dmu_object_info(os, ZVOL_OBJ, &doi); 206 207 if (error == 0) { 208 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE, 209 doi.doi_data_block_size); 210 } 211 212 return (error); 213 } 214 215 /* 216 * Find a free minor number. 217 */ 218 static minor_t 219 zvol_minor_alloc(void) 220 { 221 minor_t minor; 222 223 ASSERT(MUTEX_HELD(&zvol_state_lock)); 224 225 for (minor = 1; minor <= ZVOL_MAX_MINOR; minor++) 226 if (ddi_get_soft_state(zvol_state, minor) == NULL) 227 return (minor); 228 229 return (0); 230 } 231 232 static zvol_state_t * 233 zvol_minor_lookup(const char *name) 234 { 235 minor_t minor; 236 zvol_state_t *zv; 237 238 ASSERT(MUTEX_HELD(&zvol_state_lock)); 239 240 for (minor = 1; minor <= ZVOL_MAX_MINOR; minor++) { 241 zv = ddi_get_soft_state(zvol_state, minor); 242 if (zv == NULL) 243 continue; 244 if (strcmp(zv->zv_name, name) == 0) 245 break; 246 } 247 248 return (zv); 249 } 250 251 /* extent mapping arg */ 252 struct maparg { 253 zvol_state_t *ma_zv; 254 uint64_t ma_blks; 255 }; 256 257 /*ARGSUSED*/ 258 static int 259 zvol_map_block(spa_t *spa, blkptr_t *bp, const zbookmark_t *zb, 260 const dnode_phys_t *dnp, void *arg) 261 { 262 struct maparg *ma = arg; 263 zvol_extent_t *ze; 264 int bs = ma->ma_zv->zv_volblocksize; 265 266 if (bp == NULL || zb->zb_object != ZVOL_OBJ || zb->zb_level != 0) 267 return (0); 268 269 VERIFY3U(ma->ma_blks, ==, zb->zb_blkid); 270 ma->ma_blks++; 271 272 /* Abort immediately if we have encountered gang blocks */ 273 if (BP_IS_GANG(bp)) 274 return (EFRAGS); 275 276 /* 277 * See if the block is at the end of the previous extent. 278 */ 279 ze = list_tail(&ma->ma_zv->zv_extents); 280 if (ze && 281 DVA_GET_VDEV(BP_IDENTITY(bp)) == DVA_GET_VDEV(&ze->ze_dva) && 282 DVA_GET_OFFSET(BP_IDENTITY(bp)) == 283 DVA_GET_OFFSET(&ze->ze_dva) + ze->ze_nblks * bs) { 284 ze->ze_nblks++; 285 return (0); 286 } 287 288 dprintf_bp(bp, "%s", "next blkptr:"); 289 290 /* start a new extent */ 291 ze = kmem_zalloc(sizeof (zvol_extent_t), KM_SLEEP); 292 ze->ze_dva = bp->blk_dva[0]; /* structure assignment */ 293 ze->ze_nblks = 1; 294 list_insert_tail(&ma->ma_zv->zv_extents, ze); 295 return (0); 296 } 297 298 static void 299 zvol_free_extents(zvol_state_t *zv) 300 { 301 zvol_extent_t *ze; 302 303 while (ze = list_head(&zv->zv_extents)) { 304 list_remove(&zv->zv_extents, ze); 305 kmem_free(ze, sizeof (zvol_extent_t)); 306 } 307 } 308 309 static int 310 zvol_get_lbas(zvol_state_t *zv) 311 { 312 struct maparg ma; 313 int err; 314 315 ma.ma_zv = zv; 316 ma.ma_blks = 0; 317 zvol_free_extents(zv); 318 319 err = traverse_dataset(dmu_objset_ds(zv->zv_objset), 0, 320 TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA, zvol_map_block, &ma); 321 if (err || ma.ma_blks != (zv->zv_volsize / zv->zv_volblocksize)) { 322 zvol_free_extents(zv); 323 return (err ? err : EIO); 324 } 325 326 return (0); 327 } 328 329 /* ARGSUSED */ 330 void 331 zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx) 332 { 333 zfs_creat_t *zct = arg; 334 nvlist_t *nvprops = zct->zct_props; 335 int error; 336 uint64_t volblocksize, volsize; 337 338 VERIFY(nvlist_lookup_uint64(nvprops, 339 zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0); 340 if (nvlist_lookup_uint64(nvprops, 341 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0) 342 volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE); 343 344 /* 345 * These properties must be removed from the list so the generic 346 * property setting step won't apply to them. 347 */ 348 VERIFY(nvlist_remove_all(nvprops, 349 zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0); 350 (void) nvlist_remove_all(nvprops, 351 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE)); 352 353 error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize, 354 DMU_OT_NONE, 0, tx); 355 ASSERT(error == 0); 356 357 error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP, 358 DMU_OT_NONE, 0, tx); 359 ASSERT(error == 0); 360 361 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx); 362 ASSERT(error == 0); 363 } 364 365 /* 366 * Replay a TX_WRITE ZIL transaction that didn't get committed 367 * after a system failure 368 */ 369 static int 370 zvol_replay_write(zvol_state_t *zv, lr_write_t *lr, boolean_t byteswap) 371 { 372 objset_t *os = zv->zv_objset; 373 char *data = (char *)(lr + 1); /* data follows lr_write_t */ 374 uint64_t off = lr->lr_offset; 375 uint64_t len = lr->lr_length; 376 dmu_tx_t *tx; 377 int error; 378 379 if (byteswap) 380 byteswap_uint64_array(lr, sizeof (*lr)); 381 382 tx = dmu_tx_create(os); 383 dmu_tx_hold_write(tx, ZVOL_OBJ, off, len); 384 error = dmu_tx_assign(tx, zv->zv_txg_assign); 385 if (error) { 386 dmu_tx_abort(tx); 387 } else { 388 dmu_write(os, ZVOL_OBJ, off, len, data, tx); 389 dmu_tx_commit(tx); 390 } 391 392 return (error); 393 } 394 395 /* ARGSUSED */ 396 static int 397 zvol_replay_err(zvol_state_t *zv, lr_t *lr, boolean_t byteswap) 398 { 399 return (ENOTSUP); 400 } 401 402 /* 403 * Callback vectors for replaying records. 404 * Only TX_WRITE is needed for zvol. 405 */ 406 zil_replay_func_t *zvol_replay_vector[TX_MAX_TYPE] = { 407 zvol_replay_err, /* 0 no such transaction type */ 408 zvol_replay_err, /* TX_CREATE */ 409 zvol_replay_err, /* TX_MKDIR */ 410 zvol_replay_err, /* TX_MKXATTR */ 411 zvol_replay_err, /* TX_SYMLINK */ 412 zvol_replay_err, /* TX_REMOVE */ 413 zvol_replay_err, /* TX_RMDIR */ 414 zvol_replay_err, /* TX_LINK */ 415 zvol_replay_err, /* TX_RENAME */ 416 zvol_replay_write, /* TX_WRITE */ 417 zvol_replay_err, /* TX_TRUNCATE */ 418 zvol_replay_err, /* TX_SETATTR */ 419 zvol_replay_err, /* TX_ACL */ 420 }; 421 422 /* 423 * Create a minor node (plus a whole lot more) for the specified volume. 424 */ 425 int 426 zvol_create_minor(const char *name, major_t maj) 427 { 428 zvol_state_t *zv; 429 objset_t *os; 430 dmu_object_info_t doi; 431 uint64_t volsize; 432 minor_t minor = 0; 433 struct pathname linkpath; 434 int ds_mode = DS_MODE_OWNER; 435 vnode_t *vp = NULL; 436 char *devpath; 437 size_t devpathlen = strlen(ZVOL_FULL_DEV_DIR) + strlen(name) + 1; 438 char chrbuf[30], blkbuf[30]; 439 int error; 440 441 mutex_enter(&zvol_state_lock); 442 443 if ((zv = zvol_minor_lookup(name)) != NULL) { 444 mutex_exit(&zvol_state_lock); 445 return (EEXIST); 446 } 447 448 if (strchr(name, '@') != 0) 449 ds_mode |= DS_MODE_READONLY; 450 451 error = dmu_objset_open(name, DMU_OST_ZVOL, ds_mode, &os); 452 453 if (error) { 454 mutex_exit(&zvol_state_lock); 455 return (error); 456 } 457 458 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize); 459 460 if (error) { 461 dmu_objset_close(os); 462 mutex_exit(&zvol_state_lock); 463 return (error); 464 } 465 466 /* 467 * If there's an existing /dev/zvol symlink, try to use the 468 * same minor number we used last time. 469 */ 470 devpath = kmem_alloc(devpathlen, KM_SLEEP); 471 472 (void) sprintf(devpath, "%s%s", ZVOL_FULL_DEV_DIR, name); 473 474 error = lookupname(devpath, UIO_SYSSPACE, NO_FOLLOW, NULL, &vp); 475 476 kmem_free(devpath, devpathlen); 477 478 if (error == 0 && vp->v_type != VLNK) 479 error = EINVAL; 480 481 if (error == 0) { 482 pn_alloc(&linkpath); 483 error = pn_getsymlink(vp, &linkpath, kcred); 484 if (error == 0) { 485 char *ms = strstr(linkpath.pn_path, ZVOL_PSEUDO_DEV); 486 if (ms != NULL) { 487 ms += strlen(ZVOL_PSEUDO_DEV); 488 minor = stoi(&ms); 489 } 490 } 491 pn_free(&linkpath); 492 } 493 494 if (vp != NULL) 495 VN_RELE(vp); 496 497 /* 498 * If we found a minor but it's already in use, we must pick a new one. 499 */ 500 if (minor != 0 && ddi_get_soft_state(zvol_state, minor) != NULL) 501 minor = 0; 502 503 if (minor == 0) 504 minor = zvol_minor_alloc(); 505 506 if (minor == 0) { 507 dmu_objset_close(os); 508 mutex_exit(&zvol_state_lock); 509 return (ENXIO); 510 } 511 512 if (ddi_soft_state_zalloc(zvol_state, minor) != DDI_SUCCESS) { 513 dmu_objset_close(os); 514 mutex_exit(&zvol_state_lock); 515 return (EAGAIN); 516 } 517 518 (void) ddi_prop_update_string(minor, zfs_dip, ZVOL_PROP_NAME, 519 (char *)name); 520 521 (void) sprintf(chrbuf, "%uc,raw", minor); 522 523 if (ddi_create_minor_node(zfs_dip, chrbuf, S_IFCHR, 524 minor, DDI_PSEUDO, 0) == DDI_FAILURE) { 525 ddi_soft_state_free(zvol_state, minor); 526 dmu_objset_close(os); 527 mutex_exit(&zvol_state_lock); 528 return (EAGAIN); 529 } 530 531 (void) sprintf(blkbuf, "%uc", minor); 532 533 if (ddi_create_minor_node(zfs_dip, blkbuf, S_IFBLK, 534 minor, DDI_PSEUDO, 0) == DDI_FAILURE) { 535 ddi_remove_minor_node(zfs_dip, chrbuf); 536 ddi_soft_state_free(zvol_state, minor); 537 dmu_objset_close(os); 538 mutex_exit(&zvol_state_lock); 539 return (EAGAIN); 540 } 541 542 zv = ddi_get_soft_state(zvol_state, minor); 543 544 (void) strcpy(zv->zv_name, name); 545 zv->zv_min_bs = DEV_BSHIFT; 546 zv->zv_minor = minor; 547 zv->zv_volsize = volsize; 548 zv->zv_objset = os; 549 zv->zv_mode = ds_mode; 550 zv->zv_zilog = zil_open(os, zvol_get_data); 551 mutex_init(&zv->zv_znode.z_range_lock, NULL, MUTEX_DEFAULT, NULL); 552 avl_create(&zv->zv_znode.z_range_avl, zfs_range_compare, 553 sizeof (rl_t), offsetof(rl_t, r_node)); 554 list_create(&zv->zv_extents, sizeof (zvol_extent_t), 555 offsetof(zvol_extent_t, ze_node)); 556 /* get and cache the blocksize */ 557 error = dmu_object_info(os, ZVOL_OBJ, &doi); 558 ASSERT(error == 0); 559 zv->zv_volblocksize = doi.doi_data_block_size; 560 561 zil_replay(os, zv, &zv->zv_txg_assign, zvol_replay_vector, NULL); 562 zvol_size_changed(zv, maj); 563 564 /* XXX this should handle the possible i/o error */ 565 VERIFY(dsl_prop_register(dmu_objset_ds(zv->zv_objset), 566 "readonly", zvol_readonly_changed_cb, zv) == 0); 567 568 zvol_minors++; 569 570 mutex_exit(&zvol_state_lock); 571 572 return (0); 573 } 574 575 /* 576 * Remove minor node for the specified volume. 577 */ 578 int 579 zvol_remove_minor(const char *name) 580 { 581 zvol_state_t *zv; 582 char namebuf[30]; 583 584 mutex_enter(&zvol_state_lock); 585 586 if ((zv = zvol_minor_lookup(name)) == NULL) { 587 mutex_exit(&zvol_state_lock); 588 return (ENXIO); 589 } 590 591 if (zv->zv_total_opens != 0) { 592 mutex_exit(&zvol_state_lock); 593 return (EBUSY); 594 } 595 596 (void) sprintf(namebuf, "%uc,raw", zv->zv_minor); 597 ddi_remove_minor_node(zfs_dip, namebuf); 598 599 (void) sprintf(namebuf, "%uc", zv->zv_minor); 600 ddi_remove_minor_node(zfs_dip, namebuf); 601 602 VERIFY(dsl_prop_unregister(dmu_objset_ds(zv->zv_objset), 603 "readonly", zvol_readonly_changed_cb, zv) == 0); 604 605 zil_close(zv->zv_zilog); 606 zv->zv_zilog = NULL; 607 dmu_objset_close(zv->zv_objset); 608 zv->zv_objset = NULL; 609 avl_destroy(&zv->zv_znode.z_range_avl); 610 mutex_destroy(&zv->zv_znode.z_range_lock); 611 612 ddi_soft_state_free(zvol_state, zv->zv_minor); 613 614 zvol_minors--; 615 616 mutex_exit(&zvol_state_lock); 617 618 return (0); 619 } 620 621 int 622 zvol_prealloc(zvol_state_t *zv) 623 { 624 objset_t *os = zv->zv_objset; 625 dmu_tx_t *tx; 626 uint64_t refd, avail, usedobjs, availobjs; 627 uint64_t resid = zv->zv_volsize; 628 uint64_t off = 0; 629 630 /* Check the space usage before attempting to allocate the space */ 631 dmu_objset_space(os, &refd, &avail, &usedobjs, &availobjs); 632 if (avail < zv->zv_volsize) 633 return (ENOSPC); 634 635 /* Free old extents if they exist */ 636 zvol_free_extents(zv); 637 638 while (resid != 0) { 639 int error; 640 uint64_t bytes = MIN(resid, SPA_MAXBLOCKSIZE); 641 642 tx = dmu_tx_create(os); 643 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes); 644 error = dmu_tx_assign(tx, TXG_WAIT); 645 if (error) { 646 dmu_tx_abort(tx); 647 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, off); 648 return (error); 649 } 650 dmu_prealloc(os, ZVOL_OBJ, off, bytes, tx); 651 dmu_tx_commit(tx); 652 off += bytes; 653 resid -= bytes; 654 } 655 txg_wait_synced(dmu_objset_pool(os), 0); 656 657 return (0); 658 } 659 660 int 661 zvol_update_volsize(zvol_state_t *zv, major_t maj, uint64_t volsize) 662 { 663 dmu_tx_t *tx; 664 int error; 665 666 ASSERT(MUTEX_HELD(&zvol_state_lock)); 667 668 tx = dmu_tx_create(zv->zv_objset); 669 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 670 error = dmu_tx_assign(tx, TXG_WAIT); 671 if (error) { 672 dmu_tx_abort(tx); 673 return (error); 674 } 675 676 error = zap_update(zv->zv_objset, ZVOL_ZAP_OBJ, "size", 8, 1, 677 &volsize, tx); 678 dmu_tx_commit(tx); 679 680 if (error == 0) 681 error = dmu_free_long_range(zv->zv_objset, 682 ZVOL_OBJ, volsize, DMU_OBJECT_END); 683 684 /* 685 * If we are using a faked-up state (zv_minor == 0) then don't 686 * try to update the in-core zvol state. 687 */ 688 if (error == 0 && zv->zv_minor) { 689 zv->zv_volsize = volsize; 690 zvol_size_changed(zv, maj); 691 } 692 return (error); 693 } 694 695 int 696 zvol_set_volsize(const char *name, major_t maj, uint64_t volsize) 697 { 698 zvol_state_t *zv; 699 int error; 700 dmu_object_info_t doi; 701 uint64_t old_volsize = 0ULL; 702 zvol_state_t state = { 0 }; 703 704 mutex_enter(&zvol_state_lock); 705 706 if ((zv = zvol_minor_lookup(name)) == NULL) { 707 /* 708 * If we are doing a "zfs clone -o volsize=", then the 709 * minor node won't exist yet. 710 */ 711 error = dmu_objset_open(name, DMU_OST_ZVOL, DS_MODE_OWNER, 712 &state.zv_objset); 713 if (error != 0) 714 goto out; 715 zv = &state; 716 } 717 old_volsize = zv->zv_volsize; 718 719 if ((error = dmu_object_info(zv->zv_objset, ZVOL_OBJ, &doi)) != 0 || 720 (error = zvol_check_volsize(volsize, 721 doi.doi_data_block_size)) != 0) 722 goto out; 723 724 if (zv->zv_flags & ZVOL_RDONLY || (zv->zv_mode & DS_MODE_READONLY)) { 725 error = EROFS; 726 goto out; 727 } 728 729 error = zvol_update_volsize(zv, maj, volsize); 730 731 /* 732 * Reinitialize the dump area to the new size. If we 733 * failed to resize the dump area then restore the it back to 734 * it's original size. 735 */ 736 if (error == 0 && zv->zv_flags & ZVOL_DUMPIFIED) { 737 if ((error = zvol_dumpify(zv)) != 0 || 738 (error = dumpvp_resize()) != 0) { 739 (void) zvol_update_volsize(zv, maj, old_volsize); 740 error = zvol_dumpify(zv); 741 } 742 } 743 744 out: 745 if (state.zv_objset) 746 dmu_objset_close(state.zv_objset); 747 748 mutex_exit(&zvol_state_lock); 749 750 return (error); 751 } 752 753 int 754 zvol_set_volblocksize(const char *name, uint64_t volblocksize) 755 { 756 zvol_state_t *zv; 757 dmu_tx_t *tx; 758 int error; 759 boolean_t needlock; 760 761 /* 762 * The lock may already be held if we are being called from 763 * zvol_dump_init(). 764 */ 765 needlock = !MUTEX_HELD(&zvol_state_lock); 766 if (needlock) 767 mutex_enter(&zvol_state_lock); 768 769 if ((zv = zvol_minor_lookup(name)) == NULL) { 770 if (needlock) 771 mutex_exit(&zvol_state_lock); 772 return (ENXIO); 773 } 774 if (zv->zv_flags & ZVOL_RDONLY || (zv->zv_mode & DS_MODE_READONLY)) { 775 if (needlock) 776 mutex_exit(&zvol_state_lock); 777 return (EROFS); 778 } 779 780 tx = dmu_tx_create(zv->zv_objset); 781 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 782 error = dmu_tx_assign(tx, TXG_WAIT); 783 if (error) { 784 dmu_tx_abort(tx); 785 } else { 786 error = dmu_object_set_blocksize(zv->zv_objset, ZVOL_OBJ, 787 volblocksize, 0, tx); 788 if (error == ENOTSUP) 789 error = EBUSY; 790 dmu_tx_commit(tx); 791 if (error == 0) 792 zv->zv_volblocksize = volblocksize; 793 } 794 795 if (needlock) 796 mutex_exit(&zvol_state_lock); 797 798 return (error); 799 } 800 801 /*ARGSUSED*/ 802 int 803 zvol_open(dev_t *devp, int flag, int otyp, cred_t *cr) 804 { 805 minor_t minor = getminor(*devp); 806 zvol_state_t *zv; 807 808 if (minor == 0) /* This is the control device */ 809 return (0); 810 811 mutex_enter(&zvol_state_lock); 812 813 zv = ddi_get_soft_state(zvol_state, minor); 814 if (zv == NULL) { 815 mutex_exit(&zvol_state_lock); 816 return (ENXIO); 817 } 818 819 ASSERT(zv->zv_objset != NULL); 820 821 if ((flag & FWRITE) && 822 (zv->zv_flags & ZVOL_RDONLY || (zv->zv_mode & DS_MODE_READONLY))) { 823 mutex_exit(&zvol_state_lock); 824 return (EROFS); 825 } 826 if (zv->zv_flags & ZVOL_EXCL) { 827 mutex_exit(&zvol_state_lock); 828 return (EBUSY); 829 } 830 if (flag & FEXCL) { 831 if (zv->zv_total_opens != 0) { 832 mutex_exit(&zvol_state_lock); 833 return (EBUSY); 834 } 835 zv->zv_flags |= ZVOL_EXCL; 836 } 837 838 if (zv->zv_open_count[otyp] == 0 || otyp == OTYP_LYR) { 839 zv->zv_open_count[otyp]++; 840 zv->zv_total_opens++; 841 } 842 843 mutex_exit(&zvol_state_lock); 844 845 return (0); 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; 854 855 if (minor == 0) /* This is the control device */ 856 return (0); 857 858 mutex_enter(&zvol_state_lock); 859 860 zv = ddi_get_soft_state(zvol_state, minor); 861 if (zv == NULL) { 862 mutex_exit(&zvol_state_lock); 863 return (ENXIO); 864 } 865 866 if (zv->zv_flags & ZVOL_EXCL) { 867 ASSERT(zv->zv_total_opens == 1); 868 zv->zv_flags &= ~ZVOL_EXCL; 869 } 870 871 /* 872 * If the open count is zero, this is a spurious close. 873 * That indicates a bug in the kernel / DDI framework. 874 */ 875 ASSERT(zv->zv_open_count[otyp] != 0); 876 ASSERT(zv->zv_total_opens != 0); 877 878 /* 879 * You may get multiple opens, but only one close. 880 */ 881 zv->zv_open_count[otyp]--; 882 zv->zv_total_opens--; 883 884 mutex_exit(&zvol_state_lock); 885 886 return (0); 887 } 888 889 static void 890 zvol_get_done(dmu_buf_t *db, void *vzgd) 891 { 892 zgd_t *zgd = (zgd_t *)vzgd; 893 rl_t *rl = zgd->zgd_rl; 894 895 dmu_buf_rele(db, vzgd); 896 zfs_range_unlock(rl); 897 zil_add_block(zgd->zgd_zilog, zgd->zgd_bp); 898 kmem_free(zgd, sizeof (zgd_t)); 899 } 900 901 /* 902 * Get data to generate a TX_WRITE intent log record. 903 */ 904 static int 905 zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio) 906 { 907 zvol_state_t *zv = arg; 908 objset_t *os = zv->zv_objset; 909 dmu_buf_t *db; 910 rl_t *rl; 911 zgd_t *zgd; 912 uint64_t boff; /* block starting offset */ 913 int dlen = lr->lr_length; /* length of user data */ 914 int error; 915 916 ASSERT(zio); 917 ASSERT(dlen != 0); 918 919 /* 920 * Write records come in two flavors: immediate and indirect. 921 * For small writes it's cheaper to store the data with the 922 * log record (immediate); for large writes it's cheaper to 923 * sync the data and get a pointer to it (indirect) so that 924 * we don't have to write the data twice. 925 */ 926 if (buf != NULL) /* immediate write */ 927 return (dmu_read(os, ZVOL_OBJ, lr->lr_offset, dlen, buf)); 928 929 zgd = (zgd_t *)kmem_alloc(sizeof (zgd_t), KM_SLEEP); 930 zgd->zgd_zilog = zv->zv_zilog; 931 zgd->zgd_bp = &lr->lr_blkptr; 932 933 /* 934 * Lock the range of the block to ensure that when the data is 935 * written out and its checksum is being calculated that no other 936 * thread can change the block. 937 */ 938 boff = P2ALIGN_TYPED(lr->lr_offset, zv->zv_volblocksize, uint64_t); 939 rl = zfs_range_lock(&zv->zv_znode, boff, zv->zv_volblocksize, 940 RL_READER); 941 zgd->zgd_rl = rl; 942 943 VERIFY(0 == dmu_buf_hold(os, ZVOL_OBJ, lr->lr_offset, zgd, &db)); 944 error = dmu_sync(zio, db, &lr->lr_blkptr, 945 lr->lr_common.lrc_txg, zvol_get_done, zgd); 946 if (error == 0) 947 zil_add_block(zv->zv_zilog, &lr->lr_blkptr); 948 /* 949 * If we get EINPROGRESS, then we need to wait for a 950 * write IO initiated by dmu_sync() to complete before 951 * we can release this dbuf. We will finish everything 952 * up in the zvol_get_done() callback. 953 */ 954 if (error == EINPROGRESS) 955 return (0); 956 dmu_buf_rele(db, zgd); 957 zfs_range_unlock(rl); 958 kmem_free(zgd, sizeof (zgd_t)); 959 return (error); 960 } 961 962 /* 963 * zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions. 964 * 965 * We store data in the log buffers if it's small enough. 966 * Otherwise we will later flush the data out via dmu_sync(). 967 */ 968 ssize_t zvol_immediate_write_sz = 32768; 969 970 static void 971 zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, offset_t off, ssize_t len) 972 { 973 uint32_t blocksize = zv->zv_volblocksize; 974 lr_write_t *lr; 975 976 while (len) { 977 ssize_t nbytes = MIN(len, blocksize - P2PHASE(off, blocksize)); 978 itx_t *itx = zil_itx_create(TX_WRITE, sizeof (*lr)); 979 980 itx->itx_wr_state = 981 len > zvol_immediate_write_sz ? WR_INDIRECT : WR_NEED_COPY; 982 itx->itx_private = zv; 983 lr = (lr_write_t *)&itx->itx_lr; 984 lr->lr_foid = ZVOL_OBJ; 985 lr->lr_offset = off; 986 lr->lr_length = nbytes; 987 lr->lr_blkoff = off - P2ALIGN_TYPED(off, blocksize, uint64_t); 988 BP_ZERO(&lr->lr_blkptr); 989 990 (void) zil_itx_assign(zv->zv_zilog, itx, tx); 991 len -= nbytes; 992 off += nbytes; 993 } 994 } 995 996 static int 997 zvol_dumpio_vdev(vdev_t *vd, void *addr, uint64_t offset, uint64_t size, 998 boolean_t doread, boolean_t isdump) 999 { 1000 vdev_disk_t *dvd; 1001 int c; 1002 int numerrors = 0; 1003 1004 for (c = 0; c < vd->vdev_children; c++) { 1005 ASSERT(vd->vdev_ops == &vdev_mirror_ops); 1006 int err = zvol_dumpio_vdev(vd->vdev_child[c], 1007 addr, offset, size, doread, isdump); 1008 ASSERT3U(err, ==, 0); 1009 if (err != 0) { 1010 numerrors++; 1011 } else if (doread) { 1012 break; 1013 } 1014 } 1015 1016 if (!vd->vdev_ops->vdev_op_leaf) 1017 return (numerrors < vd->vdev_children ? 0 : EIO); 1018 1019 ASSERT(vdev_writeable(vd)); 1020 if (!vdev_writeable(vd)) 1021 return (EIO); 1022 1023 dvd = vd->vdev_tsd; 1024 ASSERT3P(dvd, !=, NULL); 1025 offset += VDEV_LABEL_START_SIZE; 1026 1027 if (ddi_in_panic() || isdump) { 1028 ASSERT(!doread); 1029 if (doread) 1030 return (EIO); 1031 return (ldi_dump(dvd->vd_lh, addr, lbtodb(offset), 1032 lbtodb(size))); 1033 } else { 1034 return (vdev_disk_physio(dvd->vd_lh, addr, size, offset, 1035 doread ? B_READ : B_WRITE)); 1036 } 1037 } 1038 1039 static int 1040 zvol_dumpio(zvol_state_t *zv, void *addr, uint64_t offset, uint64_t size, 1041 boolean_t doread, boolean_t isdump) 1042 { 1043 vdev_t *vd; 1044 int error; 1045 zvol_extent_t *ze; 1046 spa_t *spa = dmu_objset_spa(zv->zv_objset); 1047 1048 /* Must be sector aligned, and not stradle a block boundary. */ 1049 if (P2PHASE(offset, DEV_BSIZE) || P2PHASE(size, DEV_BSIZE) || 1050 P2BOUNDARY(offset, size, zv->zv_volblocksize)) { 1051 return (EINVAL); 1052 } 1053 ASSERT(size <= zv->zv_volblocksize); 1054 1055 /* Locate the extent this belongs to */ 1056 ze = list_head(&zv->zv_extents); 1057 while (offset >= ze->ze_nblks * zv->zv_volblocksize) { 1058 offset -= ze->ze_nblks * zv->zv_volblocksize; 1059 ze = list_next(&zv->zv_extents, ze); 1060 } 1061 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER); 1062 vd = vdev_lookup_top(spa, DVA_GET_VDEV(&ze->ze_dva)); 1063 offset += DVA_GET_OFFSET(&ze->ze_dva); 1064 error = zvol_dumpio_vdev(vd, addr, offset, size, doread, isdump); 1065 spa_config_exit(spa, SCL_STATE, FTAG); 1066 return (error); 1067 } 1068 1069 int 1070 zvol_strategy(buf_t *bp) 1071 { 1072 zvol_state_t *zv = ddi_get_soft_state(zvol_state, getminor(bp->b_edev)); 1073 uint64_t off, volsize; 1074 size_t resid; 1075 char *addr; 1076 objset_t *os; 1077 rl_t *rl; 1078 int error = 0; 1079 boolean_t doread = bp->b_flags & B_READ; 1080 boolean_t is_dump = zv->zv_flags & ZVOL_DUMPIFIED; 1081 1082 if (zv == NULL) { 1083 bioerror(bp, ENXIO); 1084 biodone(bp); 1085 return (0); 1086 } 1087 1088 if (getminor(bp->b_edev) == 0) { 1089 bioerror(bp, EINVAL); 1090 biodone(bp); 1091 return (0); 1092 } 1093 1094 if (!(bp->b_flags & B_READ) && 1095 (zv->zv_flags & ZVOL_RDONLY || 1096 zv->zv_mode & DS_MODE_READONLY)) { 1097 bioerror(bp, EROFS); 1098 biodone(bp); 1099 return (0); 1100 } 1101 1102 off = ldbtob(bp->b_blkno); 1103 volsize = zv->zv_volsize; 1104 1105 os = zv->zv_objset; 1106 ASSERT(os != NULL); 1107 1108 bp_mapin(bp); 1109 addr = bp->b_un.b_addr; 1110 resid = bp->b_bcount; 1111 1112 if (resid > 0 && (off < 0 || off >= volsize)) { 1113 bioerror(bp, EIO); 1114 biodone(bp); 1115 return (0); 1116 } 1117 1118 /* 1119 * There must be no buffer changes when doing a dmu_sync() because 1120 * we can't change the data whilst calculating the checksum. 1121 */ 1122 rl = zfs_range_lock(&zv->zv_znode, off, resid, 1123 doread ? RL_READER : RL_WRITER); 1124 1125 while (resid != 0 && off < volsize) { 1126 size_t size = MIN(resid, zvol_maxphys); 1127 if (is_dump) { 1128 size = MIN(size, P2END(off, zv->zv_volblocksize) - off); 1129 error = zvol_dumpio(zv, addr, off, size, 1130 doread, B_FALSE); 1131 } else if (doread) { 1132 error = dmu_read(os, ZVOL_OBJ, off, size, addr); 1133 } else { 1134 dmu_tx_t *tx = dmu_tx_create(os); 1135 dmu_tx_hold_write(tx, ZVOL_OBJ, off, size); 1136 error = dmu_tx_assign(tx, TXG_WAIT); 1137 if (error) { 1138 dmu_tx_abort(tx); 1139 } else { 1140 dmu_write(os, ZVOL_OBJ, off, size, addr, tx); 1141 zvol_log_write(zv, tx, off, size); 1142 dmu_tx_commit(tx); 1143 } 1144 } 1145 if (error) { 1146 /* convert checksum errors into IO errors */ 1147 if (error == ECKSUM) 1148 error = EIO; 1149 break; 1150 } 1151 off += size; 1152 addr += size; 1153 resid -= size; 1154 } 1155 zfs_range_unlock(rl); 1156 1157 if ((bp->b_resid = resid) == bp->b_bcount) 1158 bioerror(bp, off > volsize ? EINVAL : error); 1159 1160 if (!(bp->b_flags & B_ASYNC) && !doread && !zil_disable && !is_dump) 1161 zil_commit(zv->zv_zilog, UINT64_MAX, ZVOL_OBJ); 1162 biodone(bp); 1163 1164 return (0); 1165 } 1166 1167 /* 1168 * Set the buffer count to the zvol maximum transfer. 1169 * Using our own routine instead of the default minphys() 1170 * means that for larger writes we write bigger buffers on X86 1171 * (128K instead of 56K) and flush the disk write cache less often 1172 * (every zvol_maxphys - currently 1MB) instead of minphys (currently 1173 * 56K on X86 and 128K on sparc). 1174 */ 1175 void 1176 zvol_minphys(struct buf *bp) 1177 { 1178 if (bp->b_bcount > zvol_maxphys) 1179 bp->b_bcount = zvol_maxphys; 1180 } 1181 1182 int 1183 zvol_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblocks) 1184 { 1185 minor_t minor = getminor(dev); 1186 zvol_state_t *zv; 1187 int error = 0; 1188 uint64_t size; 1189 uint64_t boff; 1190 uint64_t resid; 1191 1192 if (minor == 0) /* This is the control device */ 1193 return (ENXIO); 1194 1195 zv = ddi_get_soft_state(zvol_state, minor); 1196 if (zv == NULL) 1197 return (ENXIO); 1198 1199 boff = ldbtob(blkno); 1200 resid = ldbtob(nblocks); 1201 1202 VERIFY3U(boff + resid, <=, zv->zv_volsize); 1203 1204 while (resid) { 1205 size = MIN(resid, P2END(boff, zv->zv_volblocksize) - boff); 1206 error = zvol_dumpio(zv, addr, boff, size, B_FALSE, B_TRUE); 1207 if (error) 1208 break; 1209 boff += size; 1210 addr += size; 1211 resid -= size; 1212 } 1213 1214 return (error); 1215 } 1216 1217 /*ARGSUSED*/ 1218 int 1219 zvol_read(dev_t dev, uio_t *uio, cred_t *cr) 1220 { 1221 minor_t minor = getminor(dev); 1222 zvol_state_t *zv; 1223 uint64_t volsize; 1224 rl_t *rl; 1225 int error = 0; 1226 1227 if (minor == 0) /* This is the control device */ 1228 return (ENXIO); 1229 1230 zv = ddi_get_soft_state(zvol_state, minor); 1231 if (zv == NULL) 1232 return (ENXIO); 1233 1234 volsize = zv->zv_volsize; 1235 if (uio->uio_resid > 0 && 1236 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize)) 1237 return (EIO); 1238 1239 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1240 error = physio(zvol_strategy, NULL, dev, B_READ, 1241 zvol_minphys, uio); 1242 return (error); 1243 } 1244 1245 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid, 1246 RL_READER); 1247 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1248 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1249 1250 /* don't read past the end */ 1251 if (bytes > volsize - uio->uio_loffset) 1252 bytes = volsize - uio->uio_loffset; 1253 1254 error = dmu_read_uio(zv->zv_objset, ZVOL_OBJ, uio, bytes); 1255 if (error) { 1256 /* convert checksum errors into IO errors */ 1257 if (error == ECKSUM) 1258 error = EIO; 1259 break; 1260 } 1261 } 1262 zfs_range_unlock(rl); 1263 return (error); 1264 } 1265 1266 /*ARGSUSED*/ 1267 int 1268 zvol_write(dev_t dev, uio_t *uio, cred_t *cr) 1269 { 1270 minor_t minor = getminor(dev); 1271 zvol_state_t *zv; 1272 uint64_t volsize; 1273 rl_t *rl; 1274 int error = 0; 1275 1276 if (minor == 0) /* This is the control device */ 1277 return (ENXIO); 1278 1279 zv = ddi_get_soft_state(zvol_state, minor); 1280 if (zv == NULL) 1281 return (ENXIO); 1282 1283 volsize = zv->zv_volsize; 1284 if (uio->uio_resid > 0 && 1285 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize)) 1286 return (EIO); 1287 1288 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1289 error = physio(zvol_strategy, NULL, dev, B_WRITE, 1290 zvol_minphys, uio); 1291 return (error); 1292 } 1293 1294 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid, 1295 RL_WRITER); 1296 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1297 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1298 uint64_t off = uio->uio_loffset; 1299 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset); 1300 1301 if (bytes > volsize - off) /* don't write past the end */ 1302 bytes = volsize - off; 1303 1304 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes); 1305 error = dmu_tx_assign(tx, TXG_WAIT); 1306 if (error) { 1307 dmu_tx_abort(tx); 1308 break; 1309 } 1310 error = dmu_write_uio(zv->zv_objset, ZVOL_OBJ, uio, bytes, tx); 1311 if (error == 0) 1312 zvol_log_write(zv, tx, off, bytes); 1313 dmu_tx_commit(tx); 1314 1315 if (error) 1316 break; 1317 } 1318 zfs_range_unlock(rl); 1319 return (error); 1320 } 1321 1322 int 1323 zvol_getefi(void *arg, int flag, uint64_t vs, uint8_t bs) 1324 { 1325 struct uuid uuid = EFI_RESERVED; 1326 efi_gpe_t gpe = { 0 }; 1327 uint32_t crc; 1328 dk_efi_t efi; 1329 int length; 1330 char *ptr; 1331 1332 if (ddi_copyin(arg, &efi, sizeof (dk_efi_t), flag)) 1333 return (EFAULT); 1334 ptr = (char *)(uintptr_t)efi.dki_data_64; 1335 length = efi.dki_length; 1336 /* 1337 * Some clients may attempt to request a PMBR for the 1338 * zvol. Currently this interface will return EINVAL to 1339 * such requests. These requests could be supported by 1340 * adding a check for lba == 0 and consing up an appropriate 1341 * PMBR. 1342 */ 1343 if (efi.dki_lba < 1 || efi.dki_lba > 2 || length <= 0) 1344 return (EINVAL); 1345 1346 gpe.efi_gpe_StartingLBA = LE_64(34ULL); 1347 gpe.efi_gpe_EndingLBA = LE_64((vs >> bs) - 1); 1348 UUID_LE_CONVERT(gpe.efi_gpe_PartitionTypeGUID, uuid); 1349 1350 if (efi.dki_lba == 1) { 1351 efi_gpt_t gpt = { 0 }; 1352 1353 gpt.efi_gpt_Signature = LE_64(EFI_SIGNATURE); 1354 gpt.efi_gpt_Revision = LE_32(EFI_VERSION_CURRENT); 1355 gpt.efi_gpt_HeaderSize = LE_32(sizeof (gpt)); 1356 gpt.efi_gpt_MyLBA = LE_64(1ULL); 1357 gpt.efi_gpt_FirstUsableLBA = LE_64(34ULL); 1358 gpt.efi_gpt_LastUsableLBA = LE_64((vs >> bs) - 1); 1359 gpt.efi_gpt_PartitionEntryLBA = LE_64(2ULL); 1360 gpt.efi_gpt_NumberOfPartitionEntries = LE_32(1); 1361 gpt.efi_gpt_SizeOfPartitionEntry = 1362 LE_32(sizeof (efi_gpe_t)); 1363 CRC32(crc, &gpe, sizeof (gpe), -1U, crc32_table); 1364 gpt.efi_gpt_PartitionEntryArrayCRC32 = LE_32(~crc); 1365 CRC32(crc, &gpt, sizeof (gpt), -1U, crc32_table); 1366 gpt.efi_gpt_HeaderCRC32 = LE_32(~crc); 1367 if (ddi_copyout(&gpt, ptr, MIN(sizeof (gpt), length), 1368 flag)) 1369 return (EFAULT); 1370 ptr += sizeof (gpt); 1371 length -= sizeof (gpt); 1372 } 1373 if (length > 0 && ddi_copyout(&gpe, ptr, MIN(sizeof (gpe), 1374 length), flag)) 1375 return (EFAULT); 1376 return (0); 1377 } 1378 1379 /* 1380 * Dirtbag ioctls to support mkfs(1M) for UFS filesystems. See dkio(7I). 1381 */ 1382 /*ARGSUSED*/ 1383 int 1384 zvol_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp) 1385 { 1386 zvol_state_t *zv; 1387 struct dk_cinfo dki; 1388 struct dk_minfo dkm; 1389 struct dk_callback *dkc; 1390 int error = 0; 1391 rl_t *rl; 1392 1393 mutex_enter(&zvol_state_lock); 1394 1395 zv = ddi_get_soft_state(zvol_state, getminor(dev)); 1396 1397 if (zv == NULL) { 1398 mutex_exit(&zvol_state_lock); 1399 return (ENXIO); 1400 } 1401 1402 switch (cmd) { 1403 1404 case DKIOCINFO: 1405 bzero(&dki, sizeof (dki)); 1406 (void) strcpy(dki.dki_cname, "zvol"); 1407 (void) strcpy(dki.dki_dname, "zvol"); 1408 dki.dki_ctype = DKC_UNKNOWN; 1409 dki.dki_maxtransfer = 1 << (SPA_MAXBLOCKSHIFT - zv->zv_min_bs); 1410 mutex_exit(&zvol_state_lock); 1411 if (ddi_copyout(&dki, (void *)arg, sizeof (dki), flag)) 1412 error = EFAULT; 1413 return (error); 1414 1415 case DKIOCGMEDIAINFO: 1416 bzero(&dkm, sizeof (dkm)); 1417 dkm.dki_lbsize = 1U << zv->zv_min_bs; 1418 dkm.dki_capacity = zv->zv_volsize >> zv->zv_min_bs; 1419 dkm.dki_media_type = DK_UNKNOWN; 1420 mutex_exit(&zvol_state_lock); 1421 if (ddi_copyout(&dkm, (void *)arg, sizeof (dkm), flag)) 1422 error = EFAULT; 1423 return (error); 1424 1425 case DKIOCGETEFI: 1426 { 1427 uint64_t vs = zv->zv_volsize; 1428 uint8_t bs = zv->zv_min_bs; 1429 1430 mutex_exit(&zvol_state_lock); 1431 error = zvol_getefi((void *)arg, flag, vs, bs); 1432 return (error); 1433 } 1434 1435 case DKIOCFLUSHWRITECACHE: 1436 dkc = (struct dk_callback *)arg; 1437 zil_commit(zv->zv_zilog, UINT64_MAX, ZVOL_OBJ); 1438 if ((flag & FKIOCTL) && dkc != NULL && dkc->dkc_callback) { 1439 (*dkc->dkc_callback)(dkc->dkc_cookie, error); 1440 error = 0; 1441 } 1442 break; 1443 1444 case DKIOCGGEOM: 1445 case DKIOCGVTOC: 1446 /* 1447 * commands using these (like prtvtoc) expect ENOTSUP 1448 * since we're emulating an EFI label 1449 */ 1450 error = ENOTSUP; 1451 break; 1452 1453 case DKIOCDUMPINIT: 1454 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize, 1455 RL_WRITER); 1456 error = zvol_dumpify(zv); 1457 zfs_range_unlock(rl); 1458 break; 1459 1460 case DKIOCDUMPFINI: 1461 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize, 1462 RL_WRITER); 1463 error = zvol_dump_fini(zv); 1464 zfs_range_unlock(rl); 1465 break; 1466 1467 default: 1468 error = ENOTTY; 1469 break; 1470 1471 } 1472 mutex_exit(&zvol_state_lock); 1473 return (error); 1474 } 1475 1476 int 1477 zvol_busy(void) 1478 { 1479 return (zvol_minors != 0); 1480 } 1481 1482 void 1483 zvol_init(void) 1484 { 1485 VERIFY(ddi_soft_state_init(&zvol_state, sizeof (zvol_state_t), 1) == 0); 1486 mutex_init(&zvol_state_lock, NULL, MUTEX_DEFAULT, NULL); 1487 } 1488 1489 void 1490 zvol_fini(void) 1491 { 1492 mutex_destroy(&zvol_state_lock); 1493 ddi_soft_state_fini(&zvol_state); 1494 } 1495 1496 static boolean_t 1497 zvol_is_swap(zvol_state_t *zv) 1498 { 1499 vnode_t *vp; 1500 boolean_t ret = B_FALSE; 1501 char *devpath; 1502 size_t devpathlen; 1503 int error; 1504 1505 devpathlen = strlen(ZVOL_FULL_DEV_DIR) + strlen(zv->zv_name) + 1; 1506 devpath = kmem_alloc(devpathlen, KM_SLEEP); 1507 (void) sprintf(devpath, "%s%s", ZVOL_FULL_DEV_DIR, zv->zv_name); 1508 error = lookupname(devpath, UIO_SYSSPACE, FOLLOW, NULLVPP, &vp); 1509 kmem_free(devpath, devpathlen); 1510 1511 ret = !error && IS_SWAPVP(common_specvp(vp)); 1512 1513 if (vp != NULL) 1514 VN_RELE(vp); 1515 1516 return (ret); 1517 } 1518 1519 static int 1520 zvol_dump_init(zvol_state_t *zv, boolean_t resize) 1521 { 1522 dmu_tx_t *tx; 1523 int error = 0; 1524 objset_t *os = zv->zv_objset; 1525 nvlist_t *nv = NULL; 1526 1527 ASSERT(MUTEX_HELD(&zvol_state_lock)); 1528 1529 tx = dmu_tx_create(os); 1530 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 1531 error = dmu_tx_assign(tx, TXG_WAIT); 1532 if (error) { 1533 dmu_tx_abort(tx); 1534 return (error); 1535 } 1536 1537 /* 1538 * If we are resizing the dump device then we only need to 1539 * update the refreservation to match the newly updated 1540 * zvolsize. Otherwise, we save off the original state of the 1541 * zvol so that we can restore them if the zvol is ever undumpified. 1542 */ 1543 if (resize) { 1544 error = zap_update(os, ZVOL_ZAP_OBJ, 1545 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 1546 &zv->zv_volsize, tx); 1547 } else { 1548 uint64_t checksum, compress, refresrv, vbs; 1549 1550 error = dsl_prop_get_integer(zv->zv_name, 1551 zfs_prop_to_name(ZFS_PROP_COMPRESSION), &compress, NULL); 1552 error = error ? error : dsl_prop_get_integer(zv->zv_name, 1553 zfs_prop_to_name(ZFS_PROP_CHECKSUM), &checksum, NULL); 1554 error = error ? error : dsl_prop_get_integer(zv->zv_name, 1555 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &refresrv, NULL); 1556 error = error ? error : dsl_prop_get_integer(zv->zv_name, 1557 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &vbs, NULL); 1558 1559 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1560 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, 1561 &compress, tx); 1562 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1563 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum, tx); 1564 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1565 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 1566 &refresrv, tx); 1567 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1568 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, 1569 &vbs, tx); 1570 } 1571 dmu_tx_commit(tx); 1572 1573 /* Truncate the file */ 1574 if (!error) 1575 error = dmu_free_long_range(zv->zv_objset, 1576 ZVOL_OBJ, 0, DMU_OBJECT_END); 1577 1578 if (error) 1579 return (error); 1580 1581 /* 1582 * We only need update the zvol's property if we are initializing 1583 * the dump area for the first time. 1584 */ 1585 if (!resize) { 1586 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 1587 VERIFY(nvlist_add_uint64(nv, 1588 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 0) == 0); 1589 VERIFY(nvlist_add_uint64(nv, 1590 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 1591 ZIO_COMPRESS_OFF) == 0); 1592 VERIFY(nvlist_add_uint64(nv, 1593 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 1594 ZIO_CHECKSUM_OFF) == 0); 1595 VERIFY(nvlist_add_uint64(nv, 1596 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 1597 SPA_MAXBLOCKSIZE) == 0); 1598 1599 error = zfs_set_prop_nvlist(zv->zv_name, nv); 1600 nvlist_free(nv); 1601 1602 if (error) 1603 return (error); 1604 } 1605 1606 /* Allocate the space for the dump */ 1607 error = zvol_prealloc(zv); 1608 return (error); 1609 } 1610 1611 static int 1612 zvol_dumpify(zvol_state_t *zv) 1613 { 1614 int error = 0; 1615 uint64_t dumpsize = 0; 1616 dmu_tx_t *tx; 1617 objset_t *os = zv->zv_objset; 1618 1619 if (zv->zv_flags & ZVOL_RDONLY || (zv->zv_mode & DS_MODE_READONLY)) 1620 return (EROFS); 1621 1622 /* 1623 * We do not support swap devices acting as dump devices. 1624 */ 1625 if (zvol_is_swap(zv)) 1626 return (ENOTSUP); 1627 1628 if (zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 1629 8, 1, &dumpsize) != 0 || dumpsize != zv->zv_volsize) { 1630 boolean_t resize = (dumpsize > 0) ? B_TRUE : B_FALSE; 1631 1632 if ((error = zvol_dump_init(zv, resize)) != 0) { 1633 (void) zvol_dump_fini(zv); 1634 return (error); 1635 } 1636 } 1637 1638 /* 1639 * Build up our lba mapping. 1640 */ 1641 error = zvol_get_lbas(zv); 1642 if (error) { 1643 (void) zvol_dump_fini(zv); 1644 return (error); 1645 } 1646 1647 tx = dmu_tx_create(os); 1648 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 1649 error = dmu_tx_assign(tx, TXG_WAIT); 1650 if (error) { 1651 dmu_tx_abort(tx); 1652 (void) zvol_dump_fini(zv); 1653 return (error); 1654 } 1655 1656 zv->zv_flags |= ZVOL_DUMPIFIED; 1657 error = zap_update(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 8, 1, 1658 &zv->zv_volsize, tx); 1659 dmu_tx_commit(tx); 1660 1661 if (error) { 1662 (void) zvol_dump_fini(zv); 1663 return (error); 1664 } 1665 1666 txg_wait_synced(dmu_objset_pool(os), 0); 1667 return (0); 1668 } 1669 1670 static int 1671 zvol_dump_fini(zvol_state_t *zv) 1672 { 1673 dmu_tx_t *tx; 1674 objset_t *os = zv->zv_objset; 1675 nvlist_t *nv; 1676 int error = 0; 1677 uint64_t checksum, compress, refresrv, vbs; 1678 1679 /* 1680 * Attempt to restore the zvol back to its pre-dumpified state. 1681 * This is a best-effort attempt as it's possible that not all 1682 * of these properties were initialized during the dumpify process 1683 * (i.e. error during zvol_dump_init). 1684 */ 1685 1686 tx = dmu_tx_create(os); 1687 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 1688 error = dmu_tx_assign(tx, TXG_WAIT); 1689 if (error) { 1690 dmu_tx_abort(tx); 1691 return (error); 1692 } 1693 (void) zap_remove(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, tx); 1694 dmu_tx_commit(tx); 1695 1696 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 1697 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum); 1698 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 1699 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, &compress); 1700 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 1701 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, &refresrv); 1702 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 1703 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, &vbs); 1704 1705 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 1706 (void) nvlist_add_uint64(nv, 1707 zfs_prop_to_name(ZFS_PROP_CHECKSUM), checksum); 1708 (void) nvlist_add_uint64(nv, 1709 zfs_prop_to_name(ZFS_PROP_COMPRESSION), compress); 1710 (void) nvlist_add_uint64(nv, 1711 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), refresrv); 1712 (void) nvlist_add_uint64(nv, 1713 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), vbs); 1714 (void) zfs_set_prop_nvlist(zv->zv_name, nv); 1715 nvlist_free(nv); 1716 1717 zvol_free_extents(zv); 1718 zv->zv_flags &= ~ZVOL_DUMPIFIED; 1719 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, DMU_OBJECT_END); 1720 1721 return (0); 1722 } 1723