zvol.c revision 263987
1/* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21/* 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * 24 * Copyright (c) 2006-2010 Pawel Jakub Dawidek <pjd@FreeBSD.org> 25 * All rights reserved. 26 * Copyright (c) 2013 by Delphix. All rights reserved. 27 * Copyright (c) 2013, Joyent, Inc. All rights reserved. 28 */ 29 30/* Portions Copyright 2010 Robert Milkowski */ 31/* Portions Copyright 2011 Martin Matuska <mm@FreeBSD.org> */ 32 33/* 34 * ZFS volume emulation driver. 35 * 36 * Makes a DMU object look like a volume of arbitrary size, up to 2^64 bytes. 37 * Volumes are accessed through the symbolic links named: 38 * 39 * /dev/zvol/dsk/<pool_name>/<dataset_name> 40 * /dev/zvol/rdsk/<pool_name>/<dataset_name> 41 * 42 * These links are created by the /dev filesystem (sdev_zvolops.c). 43 * Volumes are persistent through reboot. No user command needs to be 44 * run before opening and using a device. 45 * 46 * FreeBSD notes. 47 * On FreeBSD ZVOLs are simply GEOM providers like any other storage device 48 * in the system. 49 */ 50 51#include <sys/types.h> 52#include <sys/param.h> 53#include <sys/kernel.h> 54#include <sys/errno.h> 55#include <sys/uio.h> 56#include <sys/bio.h> 57#include <sys/buf.h> 58#include <sys/kmem.h> 59#include <sys/conf.h> 60#include <sys/cmn_err.h> 61#include <sys/stat.h> 62#include <sys/zap.h> 63#include <sys/spa.h> 64#include <sys/spa_impl.h> 65#include <sys/zio.h> 66#include <sys/dmu_traverse.h> 67#include <sys/dnode.h> 68#include <sys/dsl_dataset.h> 69#include <sys/dsl_prop.h> 70#include <sys/dkio.h> 71#include <sys/byteorder.h> 72#include <sys/sunddi.h> 73#include <sys/dirent.h> 74#include <sys/policy.h> 75#include <sys/fs/zfs.h> 76#include <sys/zfs_ioctl.h> 77#include <sys/zil.h> 78#include <sys/refcount.h> 79#include <sys/zfs_znode.h> 80#include <sys/zfs_rlock.h> 81#include <sys/vdev_impl.h> 82#include <sys/vdev_raidz.h> 83#include <sys/zvol.h> 84#include <sys/zil_impl.h> 85#include <sys/dbuf.h> 86#include <sys/dmu_tx.h> 87#include <sys/zfeature.h> 88#include <sys/zio_checksum.h> 89 90#include <geom/geom.h> 91 92#include "zfs_namecheck.h" 93 94struct g_class zfs_zvol_class = { 95 .name = "ZFS::ZVOL", 96 .version = G_VERSION, 97}; 98 99DECLARE_GEOM_CLASS(zfs_zvol_class, zfs_zvol); 100 101void *zfsdev_state; 102static char *zvol_tag = "zvol_tag"; 103 104#define ZVOL_DUMPSIZE "dumpsize" 105 106/* 107 * The spa_namespace_lock protects the zfsdev_state structure from being 108 * modified while it's being used, e.g. an open that comes in before a 109 * create finishes. It also protects temporary opens of the dataset so that, 110 * e.g., an open doesn't get a spurious EBUSY. 111 */ 112static uint32_t zvol_minors; 113 114typedef struct zvol_extent { 115 list_node_t ze_node; 116 dva_t ze_dva; /* dva associated with this extent */ 117 uint64_t ze_nblks; /* number of blocks in extent */ 118} zvol_extent_t; 119 120/* 121 * The in-core state of each volume. 122 */ 123typedef struct zvol_state { 124 char zv_name[MAXPATHLEN]; /* pool/dd name */ 125 uint64_t zv_volsize; /* amount of space we advertise */ 126 uint64_t zv_volblocksize; /* volume block size */ 127 struct g_provider *zv_provider; /* GEOM provider */ 128 uint8_t zv_min_bs; /* minimum addressable block shift */ 129 uint8_t zv_flags; /* readonly, dumpified, etc. */ 130 objset_t *zv_objset; /* objset handle */ 131 uint32_t zv_total_opens; /* total open count */ 132 zilog_t *zv_zilog; /* ZIL handle */ 133 list_t zv_extents; /* List of extents for dump */ 134 znode_t zv_znode; /* for range locking */ 135 dmu_buf_t *zv_dbuf; /* bonus handle */ 136 int zv_state; 137 struct bio_queue_head zv_queue; 138 struct mtx zv_queue_mtx; /* zv_queue mutex */ 139} zvol_state_t; 140 141/* 142 * zvol specific flags 143 */ 144#define ZVOL_RDONLY 0x1 145#define ZVOL_DUMPIFIED 0x2 146#define ZVOL_EXCL 0x4 147#define ZVOL_WCE 0x8 148 149/* 150 * zvol maximum transfer in one DMU tx. 151 */ 152int zvol_maxphys = DMU_MAX_ACCESS/2; 153 154extern int zfs_set_prop_nvlist(const char *, zprop_source_t, 155 nvlist_t *, nvlist_t *); 156static int zvol_remove_zv(zvol_state_t *); 157static int zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio); 158static int zvol_dumpify(zvol_state_t *zv); 159static int zvol_dump_fini(zvol_state_t *zv); 160static int zvol_dump_init(zvol_state_t *zv, boolean_t resize); 161 162static zvol_state_t *zvol_geom_create(const char *name); 163static void zvol_geom_run(zvol_state_t *zv); 164static void zvol_geom_destroy(zvol_state_t *zv); 165static int zvol_geom_access(struct g_provider *pp, int acr, int acw, int ace); 166static void zvol_geom_start(struct bio *bp); 167static void zvol_geom_worker(void *arg); 168 169static void 170zvol_size_changed(zvol_state_t *zv) 171{ 172#ifdef sun 173 dev_t dev = makedevice(maj, min); 174 175 VERIFY(ddi_prop_update_int64(dev, zfs_dip, 176 "Size", volsize) == DDI_SUCCESS); 177 VERIFY(ddi_prop_update_int64(dev, zfs_dip, 178 "Nblocks", lbtodb(volsize)) == DDI_SUCCESS); 179 180 /* Notify specfs to invalidate the cached size */ 181 spec_size_invalidate(dev, VBLK); 182 spec_size_invalidate(dev, VCHR); 183#else /* !sun */ 184 struct g_provider *pp; 185 186 pp = zv->zv_provider; 187 if (pp == NULL) 188 return; 189 g_topology_lock(); 190 g_resize_provider(pp, zv->zv_volsize); 191 g_topology_unlock(); 192#endif /* !sun */ 193} 194 195int 196zvol_check_volsize(uint64_t volsize, uint64_t blocksize) 197{ 198 if (volsize == 0) 199 return (SET_ERROR(EINVAL)); 200 201 if (volsize % blocksize != 0) 202 return (SET_ERROR(EINVAL)); 203 204#ifdef _ILP32 205 if (volsize - 1 > SPEC_MAXOFFSET_T) 206 return (SET_ERROR(EOVERFLOW)); 207#endif 208 return (0); 209} 210 211int 212zvol_check_volblocksize(uint64_t volblocksize) 213{ 214 if (volblocksize < SPA_MINBLOCKSIZE || 215 volblocksize > SPA_MAXBLOCKSIZE || 216 !ISP2(volblocksize)) 217 return (SET_ERROR(EDOM)); 218 219 return (0); 220} 221 222int 223zvol_get_stats(objset_t *os, nvlist_t *nv) 224{ 225 int error; 226 dmu_object_info_t doi; 227 uint64_t val; 228 229 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val); 230 if (error) 231 return (error); 232 233 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val); 234 235 error = dmu_object_info(os, ZVOL_OBJ, &doi); 236 237 if (error == 0) { 238 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE, 239 doi.doi_data_block_size); 240 } 241 242 return (error); 243} 244 245static zvol_state_t * 246zvol_minor_lookup(const char *name) 247{ 248 struct g_provider *pp; 249 struct g_geom *gp; 250 zvol_state_t *zv = NULL; 251 252 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 253 254 g_topology_lock(); 255 LIST_FOREACH(gp, &zfs_zvol_class.geom, geom) { 256 pp = LIST_FIRST(&gp->provider); 257 if (pp == NULL) 258 continue; 259 zv = pp->private; 260 if (zv == NULL) 261 continue; 262 if (strcmp(zv->zv_name, name) == 0) 263 break; 264 } 265 g_topology_unlock(); 266 267 return (gp != NULL ? zv : NULL); 268} 269 270/* extent mapping arg */ 271struct maparg { 272 zvol_state_t *ma_zv; 273 uint64_t ma_blks; 274}; 275 276/*ARGSUSED*/ 277static int 278zvol_map_block(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, 279 const zbookmark_t *zb, const dnode_phys_t *dnp, void *arg) 280{ 281 struct maparg *ma = arg; 282 zvol_extent_t *ze; 283 int bs = ma->ma_zv->zv_volblocksize; 284 285 if (BP_IS_HOLE(bp) || 286 zb->zb_object != ZVOL_OBJ || zb->zb_level != 0) 287 return (0); 288 289 VERIFY3U(ma->ma_blks, ==, zb->zb_blkid); 290 ma->ma_blks++; 291 292 /* Abort immediately if we have encountered gang blocks */ 293 if (BP_IS_GANG(bp)) 294 return (SET_ERROR(EFRAGS)); 295 296 /* 297 * See if the block is at the end of the previous extent. 298 */ 299 ze = list_tail(&ma->ma_zv->zv_extents); 300 if (ze && 301 DVA_GET_VDEV(BP_IDENTITY(bp)) == DVA_GET_VDEV(&ze->ze_dva) && 302 DVA_GET_OFFSET(BP_IDENTITY(bp)) == 303 DVA_GET_OFFSET(&ze->ze_dva) + ze->ze_nblks * bs) { 304 ze->ze_nblks++; 305 return (0); 306 } 307 308 dprintf_bp(bp, "%s", "next blkptr:"); 309 310 /* start a new extent */ 311 ze = kmem_zalloc(sizeof (zvol_extent_t), KM_SLEEP); 312 ze->ze_dva = bp->blk_dva[0]; /* structure assignment */ 313 ze->ze_nblks = 1; 314 list_insert_tail(&ma->ma_zv->zv_extents, ze); 315 return (0); 316} 317 318static void 319zvol_free_extents(zvol_state_t *zv) 320{ 321 zvol_extent_t *ze; 322 323 while (ze = list_head(&zv->zv_extents)) { 324 list_remove(&zv->zv_extents, ze); 325 kmem_free(ze, sizeof (zvol_extent_t)); 326 } 327} 328 329static int 330zvol_get_lbas(zvol_state_t *zv) 331{ 332 objset_t *os = zv->zv_objset; 333 struct maparg ma; 334 int err; 335 336 ma.ma_zv = zv; 337 ma.ma_blks = 0; 338 zvol_free_extents(zv); 339 340 /* commit any in-flight changes before traversing the dataset */ 341 txg_wait_synced(dmu_objset_pool(os), 0); 342 err = traverse_dataset(dmu_objset_ds(os), 0, 343 TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA, zvol_map_block, &ma); 344 if (err || ma.ma_blks != (zv->zv_volsize / zv->zv_volblocksize)) { 345 zvol_free_extents(zv); 346 return (err ? err : EIO); 347 } 348 349 return (0); 350} 351 352/* ARGSUSED */ 353void 354zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx) 355{ 356 zfs_creat_t *zct = arg; 357 nvlist_t *nvprops = zct->zct_props; 358 int error; 359 uint64_t volblocksize, volsize; 360 361 VERIFY(nvlist_lookup_uint64(nvprops, 362 zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0); 363 if (nvlist_lookup_uint64(nvprops, 364 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0) 365 volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE); 366 367 /* 368 * These properties must be removed from the list so the generic 369 * property setting step won't apply to them. 370 */ 371 VERIFY(nvlist_remove_all(nvprops, 372 zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0); 373 (void) nvlist_remove_all(nvprops, 374 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE)); 375 376 error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize, 377 DMU_OT_NONE, 0, tx); 378 ASSERT(error == 0); 379 380 error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP, 381 DMU_OT_NONE, 0, tx); 382 ASSERT(error == 0); 383 384 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx); 385 ASSERT(error == 0); 386} 387 388/* 389 * Replay a TX_WRITE ZIL transaction that didn't get committed 390 * after a system failure 391 */ 392static int 393zvol_replay_write(zvol_state_t *zv, lr_write_t *lr, boolean_t byteswap) 394{ 395 objset_t *os = zv->zv_objset; 396 char *data = (char *)(lr + 1); /* data follows lr_write_t */ 397 uint64_t offset, length; 398 dmu_tx_t *tx; 399 int error; 400 401 if (byteswap) 402 byteswap_uint64_array(lr, sizeof (*lr)); 403 404 offset = lr->lr_offset; 405 length = lr->lr_length; 406 407 /* If it's a dmu_sync() block, write the whole block */ 408 if (lr->lr_common.lrc_reclen == sizeof (lr_write_t)) { 409 uint64_t blocksize = BP_GET_LSIZE(&lr->lr_blkptr); 410 if (length < blocksize) { 411 offset -= offset % blocksize; 412 length = blocksize; 413 } 414 } 415 416 tx = dmu_tx_create(os); 417 dmu_tx_hold_write(tx, ZVOL_OBJ, offset, length); 418 error = dmu_tx_assign(tx, TXG_WAIT); 419 if (error) { 420 dmu_tx_abort(tx); 421 } else { 422 dmu_write(os, ZVOL_OBJ, offset, length, data, tx); 423 dmu_tx_commit(tx); 424 } 425 426 return (error); 427} 428 429/* ARGSUSED */ 430static int 431zvol_replay_err(zvol_state_t *zv, lr_t *lr, boolean_t byteswap) 432{ 433 return (SET_ERROR(ENOTSUP)); 434} 435 436/* 437 * Callback vectors for replaying records. 438 * Only TX_WRITE is needed for zvol. 439 */ 440zil_replay_func_t *zvol_replay_vector[TX_MAX_TYPE] = { 441 zvol_replay_err, /* 0 no such transaction type */ 442 zvol_replay_err, /* TX_CREATE */ 443 zvol_replay_err, /* TX_MKDIR */ 444 zvol_replay_err, /* TX_MKXATTR */ 445 zvol_replay_err, /* TX_SYMLINK */ 446 zvol_replay_err, /* TX_REMOVE */ 447 zvol_replay_err, /* TX_RMDIR */ 448 zvol_replay_err, /* TX_LINK */ 449 zvol_replay_err, /* TX_RENAME */ 450 zvol_replay_write, /* TX_WRITE */ 451 zvol_replay_err, /* TX_TRUNCATE */ 452 zvol_replay_err, /* TX_SETATTR */ 453 zvol_replay_err, /* TX_ACL */ 454 zvol_replay_err, /* TX_CREATE_ACL */ 455 zvol_replay_err, /* TX_CREATE_ATTR */ 456 zvol_replay_err, /* TX_CREATE_ACL_ATTR */ 457 zvol_replay_err, /* TX_MKDIR_ACL */ 458 zvol_replay_err, /* TX_MKDIR_ATTR */ 459 zvol_replay_err, /* TX_MKDIR_ACL_ATTR */ 460 zvol_replay_err, /* TX_WRITE2 */ 461}; 462 463#ifdef sun 464int 465zvol_name2minor(const char *name, minor_t *minor) 466{ 467 zvol_state_t *zv; 468 469 mutex_enter(&spa_namespace_lock); 470 zv = zvol_minor_lookup(name); 471 if (minor && zv) 472 *minor = zv->zv_minor; 473 mutex_exit(&spa_namespace_lock); 474 return (zv ? 0 : -1); 475} 476#endif /* sun */ 477 478/* 479 * Create a minor node (plus a whole lot more) for the specified volume. 480 */ 481int 482zvol_create_minor(const char *name) 483{ 484 zfs_soft_state_t *zs; 485 zvol_state_t *zv; 486 objset_t *os; 487 dmu_object_info_t doi; 488 uint64_t volsize; 489 int error; 490 491 ZFS_LOG(1, "Creating ZVOL %s...", name); 492 493 mutex_enter(&spa_namespace_lock); 494 495 if (zvol_minor_lookup(name) != NULL) { 496 mutex_exit(&spa_namespace_lock); 497 return (SET_ERROR(EEXIST)); 498 } 499 500 /* lie and say we're read-only */ 501 error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, FTAG, &os); 502 503 if (error) { 504 mutex_exit(&spa_namespace_lock); 505 return (error); 506 } 507 508#ifdef sun 509 if ((minor = zfsdev_minor_alloc()) == 0) { 510 dmu_objset_disown(os, FTAG); 511 mutex_exit(&spa_namespace_lock); 512 return (SET_ERROR(ENXIO)); 513 } 514 515 if (ddi_soft_state_zalloc(zfsdev_state, minor) != DDI_SUCCESS) { 516 dmu_objset_disown(os, FTAG); 517 mutex_exit(&spa_namespace_lock); 518 return (SET_ERROR(EAGAIN)); 519 } 520 (void) ddi_prop_update_string(minor, zfs_dip, ZVOL_PROP_NAME, 521 (char *)name); 522 523 (void) snprintf(chrbuf, sizeof (chrbuf), "%u,raw", minor); 524 525 if (ddi_create_minor_node(zfs_dip, chrbuf, S_IFCHR, 526 minor, DDI_PSEUDO, 0) == DDI_FAILURE) { 527 ddi_soft_state_free(zfsdev_state, minor); 528 dmu_objset_disown(os, FTAG); 529 mutex_exit(&spa_namespace_lock); 530 return (SET_ERROR(EAGAIN)); 531 } 532 533 (void) snprintf(blkbuf, sizeof (blkbuf), "%u", minor); 534 535 if (ddi_create_minor_node(zfs_dip, blkbuf, S_IFBLK, 536 minor, DDI_PSEUDO, 0) == DDI_FAILURE) { 537 ddi_remove_minor_node(zfs_dip, chrbuf); 538 ddi_soft_state_free(zfsdev_state, minor); 539 dmu_objset_disown(os, FTAG); 540 mutex_exit(&spa_namespace_lock); 541 return (SET_ERROR(EAGAIN)); 542 } 543 544 zs = ddi_get_soft_state(zfsdev_state, minor); 545 zs->zss_type = ZSST_ZVOL; 546 zv = zs->zss_data = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP); 547#else /* !sun */ 548 549 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize); 550 if (error) { 551 ASSERT(error == 0); 552 dmu_objset_disown(os, zvol_tag); 553 mutex_exit(&spa_namespace_lock); 554 return (error); 555 } 556 557 DROP_GIANT(); 558 g_topology_lock(); 559 zv = zvol_geom_create(name); 560 zv->zv_volsize = volsize; 561 zv->zv_provider->mediasize = zv->zv_volsize; 562 563#endif /* !sun */ 564 565 (void) strlcpy(zv->zv_name, name, MAXPATHLEN); 566 zv->zv_min_bs = DEV_BSHIFT; 567 zv->zv_objset = os; 568 if (dmu_objset_is_snapshot(os) || !spa_writeable(dmu_objset_spa(os))) 569 zv->zv_flags |= ZVOL_RDONLY; 570 mutex_init(&zv->zv_znode.z_range_lock, NULL, MUTEX_DEFAULT, NULL); 571 avl_create(&zv->zv_znode.z_range_avl, zfs_range_compare, 572 sizeof (rl_t), offsetof(rl_t, r_node)); 573 list_create(&zv->zv_extents, sizeof (zvol_extent_t), 574 offsetof(zvol_extent_t, ze_node)); 575 /* get and cache the blocksize */ 576 error = dmu_object_info(os, ZVOL_OBJ, &doi); 577 ASSERT(error == 0); 578 zv->zv_volblocksize = doi.doi_data_block_size; 579 580 if (spa_writeable(dmu_objset_spa(os))) { 581 if (zil_replay_disable) 582 zil_destroy(dmu_objset_zil(os), B_FALSE); 583 else 584 zil_replay(os, zv, zvol_replay_vector); 585 } 586 dmu_objset_disown(os, FTAG); 587 zv->zv_objset = NULL; 588 589 zvol_minors++; 590 591 mutex_exit(&spa_namespace_lock); 592 593 zvol_geom_run(zv); 594 595 g_topology_unlock(); 596 PICKUP_GIANT(); 597 598 ZFS_LOG(1, "ZVOL %s created.", name); 599 600 return (0); 601} 602 603/* 604 * Remove minor node for the specified volume. 605 */ 606static int 607zvol_remove_zv(zvol_state_t *zv) 608{ 609#ifdef sun 610 minor_t minor = zv->zv_minor; 611#endif 612 613 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 614 if (zv->zv_total_opens != 0) 615 return (SET_ERROR(EBUSY)); 616 617 ZFS_LOG(1, "ZVOL %s destroyed.", zv->zv_name); 618 619#ifdef sun 620 (void) snprintf(nmbuf, sizeof (nmbuf), "%u,raw", minor); 621 ddi_remove_minor_node(zfs_dip, nmbuf); 622#endif /* sun */ 623 624 avl_destroy(&zv->zv_znode.z_range_avl); 625 mutex_destroy(&zv->zv_znode.z_range_lock); 626 627 zvol_geom_destroy(zv); 628 629 zvol_minors--; 630 return (0); 631} 632 633int 634zvol_remove_minor(const char *name) 635{ 636 zvol_state_t *zv; 637 int rc; 638 639 mutex_enter(&spa_namespace_lock); 640 if ((zv = zvol_minor_lookup(name)) == NULL) { 641 mutex_exit(&spa_namespace_lock); 642 return (SET_ERROR(ENXIO)); 643 } 644 g_topology_lock(); 645 rc = zvol_remove_zv(zv); 646 g_topology_unlock(); 647 mutex_exit(&spa_namespace_lock); 648 return (rc); 649} 650 651int 652zvol_first_open(zvol_state_t *zv) 653{ 654 objset_t *os; 655 uint64_t volsize; 656 int error; 657 uint64_t readonly; 658 659 /* lie and say we're read-only */ 660 error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, B_TRUE, 661 zvol_tag, &os); 662 if (error) 663 return (error); 664 665 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize); 666 if (error) { 667 ASSERT(error == 0); 668 dmu_objset_disown(os, zvol_tag); 669 return (error); 670 } 671 zv->zv_objset = os; 672 error = dmu_bonus_hold(os, ZVOL_OBJ, zvol_tag, &zv->zv_dbuf); 673 if (error) { 674 dmu_objset_disown(os, zvol_tag); 675 return (error); 676 } 677 zv->zv_volsize = volsize; 678 zv->zv_zilog = zil_open(os, zvol_get_data); 679 zvol_size_changed(zv); 680 681 VERIFY(dsl_prop_get_integer(zv->zv_name, "readonly", &readonly, 682 NULL) == 0); 683 if (readonly || dmu_objset_is_snapshot(os) || 684 !spa_writeable(dmu_objset_spa(os))) 685 zv->zv_flags |= ZVOL_RDONLY; 686 else 687 zv->zv_flags &= ~ZVOL_RDONLY; 688 return (error); 689} 690 691void 692zvol_last_close(zvol_state_t *zv) 693{ 694 zil_close(zv->zv_zilog); 695 zv->zv_zilog = NULL; 696 697 dmu_buf_rele(zv->zv_dbuf, zvol_tag); 698 zv->zv_dbuf = NULL; 699 700 /* 701 * Evict cached data 702 */ 703 if (dsl_dataset_is_dirty(dmu_objset_ds(zv->zv_objset)) && 704 !(zv->zv_flags & ZVOL_RDONLY)) 705 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 706 dmu_objset_evict_dbufs(zv->zv_objset); 707 708 dmu_objset_disown(zv->zv_objset, zvol_tag); 709 zv->zv_objset = NULL; 710} 711 712#ifdef sun 713int 714zvol_prealloc(zvol_state_t *zv) 715{ 716 objset_t *os = zv->zv_objset; 717 dmu_tx_t *tx; 718 uint64_t refd, avail, usedobjs, availobjs; 719 uint64_t resid = zv->zv_volsize; 720 uint64_t off = 0; 721 722 /* Check the space usage before attempting to allocate the space */ 723 dmu_objset_space(os, &refd, &avail, &usedobjs, &availobjs); 724 if (avail < zv->zv_volsize) 725 return (SET_ERROR(ENOSPC)); 726 727 /* Free old extents if they exist */ 728 zvol_free_extents(zv); 729 730 while (resid != 0) { 731 int error; 732 uint64_t bytes = MIN(resid, SPA_MAXBLOCKSIZE); 733 734 tx = dmu_tx_create(os); 735 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes); 736 error = dmu_tx_assign(tx, TXG_WAIT); 737 if (error) { 738 dmu_tx_abort(tx); 739 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, off); 740 return (error); 741 } 742 dmu_prealloc(os, ZVOL_OBJ, off, bytes, tx); 743 dmu_tx_commit(tx); 744 off += bytes; 745 resid -= bytes; 746 } 747 txg_wait_synced(dmu_objset_pool(os), 0); 748 749 return (0); 750} 751#endif /* sun */ 752 753static int 754zvol_update_volsize(objset_t *os, uint64_t volsize) 755{ 756 dmu_tx_t *tx; 757 int error; 758 759 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 760 761 tx = dmu_tx_create(os); 762 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 763 error = dmu_tx_assign(tx, TXG_WAIT); 764 if (error) { 765 dmu_tx_abort(tx); 766 return (error); 767 } 768 769 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, 770 &volsize, tx); 771 dmu_tx_commit(tx); 772 773 if (error == 0) 774 error = dmu_free_long_range(os, 775 ZVOL_OBJ, volsize, DMU_OBJECT_END); 776 return (error); 777} 778 779void 780zvol_remove_minors(const char *name) 781{ 782 struct g_geom *gp, *gptmp; 783 struct g_provider *pp; 784 zvol_state_t *zv; 785 size_t namelen; 786 787 namelen = strlen(name); 788 789 DROP_GIANT(); 790 mutex_enter(&spa_namespace_lock); 791 g_topology_lock(); 792 793 LIST_FOREACH_SAFE(gp, &zfs_zvol_class.geom, geom, gptmp) { 794 pp = LIST_FIRST(&gp->provider); 795 if (pp == NULL) 796 continue; 797 zv = pp->private; 798 if (zv == NULL) 799 continue; 800 if (strcmp(zv->zv_name, name) == 0 || 801 (strncmp(zv->zv_name, name, namelen) == 0 && 802 zv->zv_name[namelen] == '/')) { 803 (void) zvol_remove_zv(zv); 804 } 805 } 806 807 g_topology_unlock(); 808 mutex_exit(&spa_namespace_lock); 809 PICKUP_GIANT(); 810} 811 812int 813zvol_set_volsize(const char *name, major_t maj, uint64_t volsize) 814{ 815 zvol_state_t *zv = NULL; 816 objset_t *os; 817 int error; 818 dmu_object_info_t doi; 819 uint64_t old_volsize = 0ULL; 820 uint64_t readonly; 821 822 mutex_enter(&spa_namespace_lock); 823 zv = zvol_minor_lookup(name); 824 if ((error = dmu_objset_hold(name, FTAG, &os)) != 0) { 825 mutex_exit(&spa_namespace_lock); 826 return (error); 827 } 828 829 if ((error = dmu_object_info(os, ZVOL_OBJ, &doi)) != 0 || 830 (error = zvol_check_volsize(volsize, 831 doi.doi_data_block_size)) != 0) 832 goto out; 833 834 VERIFY(dsl_prop_get_integer(name, "readonly", &readonly, 835 NULL) == 0); 836 if (readonly) { 837 error = EROFS; 838 goto out; 839 } 840 841 error = zvol_update_volsize(os, volsize); 842 /* 843 * Reinitialize the dump area to the new size. If we 844 * failed to resize the dump area then restore it back to 845 * its original size. 846 */ 847 if (zv && error == 0) { 848#ifdef ZVOL_DUMP 849 if (zv->zv_flags & ZVOL_DUMPIFIED) { 850 old_volsize = zv->zv_volsize; 851 zv->zv_volsize = volsize; 852 if ((error = zvol_dumpify(zv)) != 0 || 853 (error = dumpvp_resize()) != 0) { 854 (void) zvol_update_volsize(os, old_volsize); 855 zv->zv_volsize = old_volsize; 856 error = zvol_dumpify(zv); 857 } 858 } 859#endif /* ZVOL_DUMP */ 860 if (error == 0) { 861 zv->zv_volsize = volsize; 862 zvol_size_changed(zv); 863 } 864 } 865 866#ifdef sun 867 /* 868 * Generate a LUN expansion event. 869 */ 870 if (zv && error == 0) { 871 sysevent_id_t eid; 872 nvlist_t *attr; 873 char *physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 874 875 (void) snprintf(physpath, MAXPATHLEN, "%s%u", ZVOL_PSEUDO_DEV, 876 zv->zv_minor); 877 878 VERIFY(nvlist_alloc(&attr, NV_UNIQUE_NAME, KM_SLEEP) == 0); 879 VERIFY(nvlist_add_string(attr, DEV_PHYS_PATH, physpath) == 0); 880 881 (void) ddi_log_sysevent(zfs_dip, SUNW_VENDOR, EC_DEV_STATUS, 882 ESC_DEV_DLE, attr, &eid, DDI_SLEEP); 883 884 nvlist_free(attr); 885 kmem_free(physpath, MAXPATHLEN); 886 } 887#endif /* sun */ 888 889out: 890 dmu_objset_rele(os, FTAG); 891 892 mutex_exit(&spa_namespace_lock); 893 894 return (error); 895} 896 897/*ARGSUSED*/ 898static int 899zvol_open(struct g_provider *pp, int flag, int count) 900{ 901 zvol_state_t *zv; 902 int err = 0; 903 boolean_t locked = B_FALSE; 904 905 /* 906 * Protect against recursively entering spa_namespace_lock 907 * when spa_open() is used for a pool on a (local) ZVOL(s). 908 * This is needed since we replaced upstream zfsdev_state_lock 909 * with spa_namespace_lock in the ZVOL code. 910 * We are using the same trick as spa_open(). 911 * Note that calls in zvol_first_open which need to resolve 912 * pool name to a spa object will enter spa_open() 913 * recursively, but that function already has all the 914 * necessary protection. 915 */ 916 if (!MUTEX_HELD(&spa_namespace_lock)) { 917 mutex_enter(&spa_namespace_lock); 918 locked = B_TRUE; 919 } 920 921 zv = pp->private; 922 if (zv == NULL) { 923 if (locked) 924 mutex_exit(&spa_namespace_lock); 925 return (SET_ERROR(ENXIO)); 926 } 927 928 if (zv->zv_total_opens == 0) { 929 err = zvol_first_open(zv); 930 if (err) { 931 if (locked) 932 mutex_exit(&spa_namespace_lock); 933 return (err); 934 } 935 pp->mediasize = zv->zv_volsize; 936 pp->stripeoffset = 0; 937 pp->stripesize = zv->zv_volblocksize; 938 } 939 if ((flag & FWRITE) && (zv->zv_flags & ZVOL_RDONLY)) { 940 err = SET_ERROR(EROFS); 941 goto out; 942 } 943 if (zv->zv_flags & ZVOL_EXCL) { 944 err = SET_ERROR(EBUSY); 945 goto out; 946 } 947#ifdef FEXCL 948 if (flag & FEXCL) { 949 if (zv->zv_total_opens != 0) { 950 err = SET_ERROR(EBUSY); 951 goto out; 952 } 953 zv->zv_flags |= ZVOL_EXCL; 954 } 955#endif 956 957 zv->zv_total_opens += count; 958 if (locked) 959 mutex_exit(&spa_namespace_lock); 960 961 return (err); 962out: 963 if (zv->zv_total_opens == 0) 964 zvol_last_close(zv); 965 if (locked) 966 mutex_exit(&spa_namespace_lock); 967 return (err); 968} 969 970/*ARGSUSED*/ 971static int 972zvol_close(struct g_provider *pp, int flag, int count) 973{ 974 zvol_state_t *zv; 975 int error = 0; 976 boolean_t locked = B_FALSE; 977 978 /* See comment in zvol_open(). */ 979 if (!MUTEX_HELD(&spa_namespace_lock)) { 980 mutex_enter(&spa_namespace_lock); 981 locked = B_TRUE; 982 } 983 984 zv = pp->private; 985 if (zv == NULL) { 986 if (locked) 987 mutex_exit(&spa_namespace_lock); 988 return (SET_ERROR(ENXIO)); 989 } 990 991 if (zv->zv_flags & ZVOL_EXCL) { 992 ASSERT(zv->zv_total_opens == 1); 993 zv->zv_flags &= ~ZVOL_EXCL; 994 } 995 996 /* 997 * If the open count is zero, this is a spurious close. 998 * That indicates a bug in the kernel / DDI framework. 999 */ 1000 ASSERT(zv->zv_total_opens != 0); 1001 1002 /* 1003 * You may get multiple opens, but only one close. 1004 */ 1005 zv->zv_total_opens -= count; 1006 1007 if (zv->zv_total_opens == 0) 1008 zvol_last_close(zv); 1009 1010 if (locked) 1011 mutex_exit(&spa_namespace_lock); 1012 return (error); 1013} 1014 1015static void 1016zvol_get_done(zgd_t *zgd, int error) 1017{ 1018 if (zgd->zgd_db) 1019 dmu_buf_rele(zgd->zgd_db, zgd); 1020 1021 zfs_range_unlock(zgd->zgd_rl); 1022 1023 if (error == 0 && zgd->zgd_bp) 1024 zil_add_block(zgd->zgd_zilog, zgd->zgd_bp); 1025 1026 kmem_free(zgd, sizeof (zgd_t)); 1027} 1028 1029/* 1030 * Get data to generate a TX_WRITE intent log record. 1031 */ 1032static int 1033zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio) 1034{ 1035 zvol_state_t *zv = arg; 1036 objset_t *os = zv->zv_objset; 1037 uint64_t object = ZVOL_OBJ; 1038 uint64_t offset = lr->lr_offset; 1039 uint64_t size = lr->lr_length; /* length of user data */ 1040 blkptr_t *bp = &lr->lr_blkptr; 1041 dmu_buf_t *db; 1042 zgd_t *zgd; 1043 int error; 1044 1045 ASSERT(zio != NULL); 1046 ASSERT(size != 0); 1047 1048 zgd = kmem_zalloc(sizeof (zgd_t), KM_SLEEP); 1049 zgd->zgd_zilog = zv->zv_zilog; 1050 zgd->zgd_rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER); 1051 1052 /* 1053 * Write records come in two flavors: immediate and indirect. 1054 * For small writes it's cheaper to store the data with the 1055 * log record (immediate); for large writes it's cheaper to 1056 * sync the data and get a pointer to it (indirect) so that 1057 * we don't have to write the data twice. 1058 */ 1059 if (buf != NULL) { /* immediate write */ 1060 error = dmu_read(os, object, offset, size, buf, 1061 DMU_READ_NO_PREFETCH); 1062 } else { 1063 size = zv->zv_volblocksize; 1064 offset = P2ALIGN(offset, size); 1065 error = dmu_buf_hold(os, object, offset, zgd, &db, 1066 DMU_READ_NO_PREFETCH); 1067 if (error == 0) { 1068 blkptr_t *obp = dmu_buf_get_blkptr(db); 1069 if (obp) { 1070 ASSERT(BP_IS_HOLE(bp)); 1071 *bp = *obp; 1072 } 1073 1074 zgd->zgd_db = db; 1075 zgd->zgd_bp = bp; 1076 1077 ASSERT(db->db_offset == offset); 1078 ASSERT(db->db_size == size); 1079 1080 error = dmu_sync(zio, lr->lr_common.lrc_txg, 1081 zvol_get_done, zgd); 1082 1083 if (error == 0) 1084 return (0); 1085 } 1086 } 1087 1088 zvol_get_done(zgd, error); 1089 1090 return (error); 1091} 1092 1093/* 1094 * zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions. 1095 * 1096 * We store data in the log buffers if it's small enough. 1097 * Otherwise we will later flush the data out via dmu_sync(). 1098 */ 1099ssize_t zvol_immediate_write_sz = 32768; 1100 1101static void 1102zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, offset_t off, ssize_t resid, 1103 boolean_t sync) 1104{ 1105 uint32_t blocksize = zv->zv_volblocksize; 1106 zilog_t *zilog = zv->zv_zilog; 1107 boolean_t slogging; 1108 ssize_t immediate_write_sz; 1109 1110 if (zil_replaying(zilog, tx)) 1111 return; 1112 1113 immediate_write_sz = (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT) 1114 ? 0 : zvol_immediate_write_sz; 1115 1116 slogging = spa_has_slogs(zilog->zl_spa) && 1117 (zilog->zl_logbias == ZFS_LOGBIAS_LATENCY); 1118 1119 while (resid) { 1120 itx_t *itx; 1121 lr_write_t *lr; 1122 ssize_t len; 1123 itx_wr_state_t write_state; 1124 1125 /* 1126 * Unlike zfs_log_write() we can be called with 1127 * upto DMU_MAX_ACCESS/2 (5MB) writes. 1128 */ 1129 if (blocksize > immediate_write_sz && !slogging && 1130 resid >= blocksize && off % blocksize == 0) { 1131 write_state = WR_INDIRECT; /* uses dmu_sync */ 1132 len = blocksize; 1133 } else if (sync) { 1134 write_state = WR_COPIED; 1135 len = MIN(ZIL_MAX_LOG_DATA, resid); 1136 } else { 1137 write_state = WR_NEED_COPY; 1138 len = MIN(ZIL_MAX_LOG_DATA, resid); 1139 } 1140 1141 itx = zil_itx_create(TX_WRITE, sizeof (*lr) + 1142 (write_state == WR_COPIED ? len : 0)); 1143 lr = (lr_write_t *)&itx->itx_lr; 1144 if (write_state == WR_COPIED && dmu_read(zv->zv_objset, 1145 ZVOL_OBJ, off, len, lr + 1, DMU_READ_NO_PREFETCH) != 0) { 1146 zil_itx_destroy(itx); 1147 itx = zil_itx_create(TX_WRITE, sizeof (*lr)); 1148 lr = (lr_write_t *)&itx->itx_lr; 1149 write_state = WR_NEED_COPY; 1150 } 1151 1152 itx->itx_wr_state = write_state; 1153 if (write_state == WR_NEED_COPY) 1154 itx->itx_sod += len; 1155 lr->lr_foid = ZVOL_OBJ; 1156 lr->lr_offset = off; 1157 lr->lr_length = len; 1158 lr->lr_blkoff = 0; 1159 BP_ZERO(&lr->lr_blkptr); 1160 1161 itx->itx_private = zv; 1162 itx->itx_sync = sync; 1163 1164 zil_itx_assign(zilog, itx, tx); 1165 1166 off += len; 1167 resid -= len; 1168 } 1169} 1170 1171#ifdef sun 1172static int 1173zvol_dumpio_vdev(vdev_t *vd, void *addr, uint64_t offset, uint64_t origoffset, 1174 uint64_t size, boolean_t doread, boolean_t isdump) 1175{ 1176 vdev_disk_t *dvd; 1177 int c; 1178 int numerrors = 0; 1179 1180 if (vd->vdev_ops == &vdev_mirror_ops || 1181 vd->vdev_ops == &vdev_replacing_ops || 1182 vd->vdev_ops == &vdev_spare_ops) { 1183 for (c = 0; c < vd->vdev_children; c++) { 1184 int err = zvol_dumpio_vdev(vd->vdev_child[c], 1185 addr, offset, origoffset, size, doread, isdump); 1186 if (err != 0) { 1187 numerrors++; 1188 } else if (doread) { 1189 break; 1190 } 1191 } 1192 } 1193 1194 if (!vd->vdev_ops->vdev_op_leaf && vd->vdev_ops != &vdev_raidz_ops) 1195 return (numerrors < vd->vdev_children ? 0 : EIO); 1196 1197 if (doread && !vdev_readable(vd)) 1198 return (SET_ERROR(EIO)); 1199 else if (!doread && !vdev_writeable(vd)) 1200 return (SET_ERROR(EIO)); 1201 1202 if (vd->vdev_ops == &vdev_raidz_ops) { 1203 return (vdev_raidz_physio(vd, 1204 addr, size, offset, origoffset, doread, isdump)); 1205 } 1206 1207 offset += VDEV_LABEL_START_SIZE; 1208 1209 if (ddi_in_panic() || isdump) { 1210 ASSERT(!doread); 1211 if (doread) 1212 return (SET_ERROR(EIO)); 1213 dvd = vd->vdev_tsd; 1214 ASSERT3P(dvd, !=, NULL); 1215 return (ldi_dump(dvd->vd_lh, addr, lbtodb(offset), 1216 lbtodb(size))); 1217 } else { 1218 dvd = vd->vdev_tsd; 1219 ASSERT3P(dvd, !=, NULL); 1220 return (vdev_disk_ldi_physio(dvd->vd_lh, addr, size, 1221 offset, doread ? B_READ : B_WRITE)); 1222 } 1223} 1224 1225static int 1226zvol_dumpio(zvol_state_t *zv, void *addr, uint64_t offset, uint64_t size, 1227 boolean_t doread, boolean_t isdump) 1228{ 1229 vdev_t *vd; 1230 int error; 1231 zvol_extent_t *ze; 1232 spa_t *spa = dmu_objset_spa(zv->zv_objset); 1233 1234 /* Must be sector aligned, and not stradle a block boundary. */ 1235 if (P2PHASE(offset, DEV_BSIZE) || P2PHASE(size, DEV_BSIZE) || 1236 P2BOUNDARY(offset, size, zv->zv_volblocksize)) { 1237 return (SET_ERROR(EINVAL)); 1238 } 1239 ASSERT(size <= zv->zv_volblocksize); 1240 1241 /* Locate the extent this belongs to */ 1242 ze = list_head(&zv->zv_extents); 1243 while (offset >= ze->ze_nblks * zv->zv_volblocksize) { 1244 offset -= ze->ze_nblks * zv->zv_volblocksize; 1245 ze = list_next(&zv->zv_extents, ze); 1246 } 1247 1248 if (ze == NULL) 1249 return (SET_ERROR(EINVAL)); 1250 1251 if (!ddi_in_panic()) 1252 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER); 1253 1254 vd = vdev_lookup_top(spa, DVA_GET_VDEV(&ze->ze_dva)); 1255 offset += DVA_GET_OFFSET(&ze->ze_dva); 1256 error = zvol_dumpio_vdev(vd, addr, offset, DVA_GET_OFFSET(&ze->ze_dva), 1257 size, doread, isdump); 1258 1259 if (!ddi_in_panic()) 1260 spa_config_exit(spa, SCL_STATE, FTAG); 1261 1262 return (error); 1263} 1264#endif /* sun */ 1265 1266int 1267zvol_strategy(struct bio *bp) 1268{ 1269 zvol_state_t *zv = bp->bio_to->private; 1270 uint64_t off, volsize; 1271 size_t resid; 1272 char *addr; 1273 objset_t *os; 1274 rl_t *rl; 1275 int error = 0; 1276 boolean_t doread = (bp->bio_cmd == BIO_READ); 1277 boolean_t is_dumpified; 1278 boolean_t sync; 1279 1280 if (zv == NULL) { 1281 g_io_deliver(bp, ENXIO); 1282 return (0); 1283 } 1284 1285 if (bp->bio_cmd != BIO_READ && (zv->zv_flags & ZVOL_RDONLY)) { 1286 g_io_deliver(bp, EROFS); 1287 return (0); 1288 } 1289 1290 off = bp->bio_offset; 1291 volsize = zv->zv_volsize; 1292 1293 os = zv->zv_objset; 1294 ASSERT(os != NULL); 1295 1296 addr = bp->bio_data; 1297 resid = bp->bio_length; 1298 1299 if (resid > 0 && (off < 0 || off >= volsize)) { 1300 g_io_deliver(bp, EIO); 1301 return (0); 1302 } 1303 1304#ifdef illumos 1305 is_dumpified = zv->zv_flags & ZVOL_DUMPIFIED; 1306#else 1307 is_dumpified = B_FALSE; 1308#endif 1309 sync = !doread && !is_dumpified && 1310 zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS; 1311 1312 /* 1313 * There must be no buffer changes when doing a dmu_sync() because 1314 * we can't change the data whilst calculating the checksum. 1315 */ 1316 rl = zfs_range_lock(&zv->zv_znode, off, resid, 1317 doread ? RL_READER : RL_WRITER); 1318 1319 while (resid != 0 && off < volsize) { 1320 size_t size = MIN(resid, zvol_maxphys); 1321#ifdef illumos 1322 if (is_dumpified) { 1323 size = MIN(size, P2END(off, zv->zv_volblocksize) - off); 1324 error = zvol_dumpio(zv, addr, off, size, 1325 doread, B_FALSE); 1326 } else if (doread) { 1327#else 1328 if (doread) { 1329#endif 1330 error = dmu_read(os, ZVOL_OBJ, off, size, addr, 1331 DMU_READ_PREFETCH); 1332 } else { 1333 dmu_tx_t *tx = dmu_tx_create(os); 1334 dmu_tx_hold_write(tx, ZVOL_OBJ, off, size); 1335 error = dmu_tx_assign(tx, TXG_WAIT); 1336 if (error) { 1337 dmu_tx_abort(tx); 1338 } else { 1339 dmu_write(os, ZVOL_OBJ, off, size, addr, tx); 1340 zvol_log_write(zv, tx, off, size, sync); 1341 dmu_tx_commit(tx); 1342 } 1343 } 1344 if (error) { 1345 /* convert checksum errors into IO errors */ 1346 if (error == ECKSUM) 1347 error = SET_ERROR(EIO); 1348 break; 1349 } 1350 off += size; 1351 addr += size; 1352 resid -= size; 1353 } 1354 zfs_range_unlock(rl); 1355 1356 bp->bio_completed = bp->bio_length - resid; 1357 if (bp->bio_completed < bp->bio_length) 1358 bp->bio_error = (off > volsize ? EINVAL : error); 1359 1360 if (sync) 1361 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1362 g_io_deliver(bp, 0); 1363 1364 return (0); 1365} 1366 1367#ifdef sun 1368/* 1369 * Set the buffer count to the zvol maximum transfer. 1370 * Using our own routine instead of the default minphys() 1371 * means that for larger writes we write bigger buffers on X86 1372 * (128K instead of 56K) and flush the disk write cache less often 1373 * (every zvol_maxphys - currently 1MB) instead of minphys (currently 1374 * 56K on X86 and 128K on sparc). 1375 */ 1376void 1377zvol_minphys(struct buf *bp) 1378{ 1379 if (bp->b_bcount > zvol_maxphys) 1380 bp->b_bcount = zvol_maxphys; 1381} 1382 1383int 1384zvol_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblocks) 1385{ 1386 minor_t minor = getminor(dev); 1387 zvol_state_t *zv; 1388 int error = 0; 1389 uint64_t size; 1390 uint64_t boff; 1391 uint64_t resid; 1392 1393 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1394 if (zv == NULL) 1395 return (SET_ERROR(ENXIO)); 1396 1397 if ((zv->zv_flags & ZVOL_DUMPIFIED) == 0) 1398 return (SET_ERROR(EINVAL)); 1399 1400 boff = ldbtob(blkno); 1401 resid = ldbtob(nblocks); 1402 1403 VERIFY3U(boff + resid, <=, zv->zv_volsize); 1404 1405 while (resid) { 1406 size = MIN(resid, P2END(boff, zv->zv_volblocksize) - boff); 1407 error = zvol_dumpio(zv, addr, boff, size, B_FALSE, B_TRUE); 1408 if (error) 1409 break; 1410 boff += size; 1411 addr += size; 1412 resid -= size; 1413 } 1414 1415 return (error); 1416} 1417 1418/*ARGSUSED*/ 1419int 1420zvol_read(dev_t dev, uio_t *uio, cred_t *cr) 1421{ 1422 minor_t minor = getminor(dev); 1423 zvol_state_t *zv; 1424 uint64_t volsize; 1425 rl_t *rl; 1426 int error = 0; 1427 1428 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1429 if (zv == NULL) 1430 return (SET_ERROR(ENXIO)); 1431 1432 volsize = zv->zv_volsize; 1433 if (uio->uio_resid > 0 && 1434 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize)) 1435 return (SET_ERROR(EIO)); 1436 1437 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1438 error = physio(zvol_strategy, NULL, dev, B_READ, 1439 zvol_minphys, uio); 1440 return (error); 1441 } 1442 1443 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid, 1444 RL_READER); 1445 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1446 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1447 1448 /* don't read past the end */ 1449 if (bytes > volsize - uio->uio_loffset) 1450 bytes = volsize - uio->uio_loffset; 1451 1452 error = dmu_read_uio(zv->zv_objset, ZVOL_OBJ, uio, bytes); 1453 if (error) { 1454 /* convert checksum errors into IO errors */ 1455 if (error == ECKSUM) 1456 error = SET_ERROR(EIO); 1457 break; 1458 } 1459 } 1460 zfs_range_unlock(rl); 1461 return (error); 1462} 1463 1464/*ARGSUSED*/ 1465int 1466zvol_write(dev_t dev, uio_t *uio, cred_t *cr) 1467{ 1468 minor_t minor = getminor(dev); 1469 zvol_state_t *zv; 1470 uint64_t volsize; 1471 rl_t *rl; 1472 int error = 0; 1473 boolean_t sync; 1474 1475 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1476 if (zv == NULL) 1477 return (SET_ERROR(ENXIO)); 1478 1479 volsize = zv->zv_volsize; 1480 if (uio->uio_resid > 0 && 1481 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize)) 1482 return (SET_ERROR(EIO)); 1483 1484 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1485 error = physio(zvol_strategy, NULL, dev, B_WRITE, 1486 zvol_minphys, uio); 1487 return (error); 1488 } 1489 1490 sync = !(zv->zv_flags & ZVOL_WCE) || 1491 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS); 1492 1493 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid, 1494 RL_WRITER); 1495 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1496 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1497 uint64_t off = uio->uio_loffset; 1498 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset); 1499 1500 if (bytes > volsize - off) /* don't write past the end */ 1501 bytes = volsize - off; 1502 1503 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes); 1504 error = dmu_tx_assign(tx, TXG_WAIT); 1505 if (error) { 1506 dmu_tx_abort(tx); 1507 break; 1508 } 1509 error = dmu_write_uio_dbuf(zv->zv_dbuf, uio, bytes, tx); 1510 if (error == 0) 1511 zvol_log_write(zv, tx, off, bytes, sync); 1512 dmu_tx_commit(tx); 1513 1514 if (error) 1515 break; 1516 } 1517 zfs_range_unlock(rl); 1518 if (sync) 1519 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1520 return (error); 1521} 1522 1523int 1524zvol_getefi(void *arg, int flag, uint64_t vs, uint8_t bs) 1525{ 1526 struct uuid uuid = EFI_RESERVED; 1527 efi_gpe_t gpe = { 0 }; 1528 uint32_t crc; 1529 dk_efi_t efi; 1530 int length; 1531 char *ptr; 1532 1533 if (ddi_copyin(arg, &efi, sizeof (dk_efi_t), flag)) 1534 return (SET_ERROR(EFAULT)); 1535 ptr = (char *)(uintptr_t)efi.dki_data_64; 1536 length = efi.dki_length; 1537 /* 1538 * Some clients may attempt to request a PMBR for the 1539 * zvol. Currently this interface will return EINVAL to 1540 * such requests. These requests could be supported by 1541 * adding a check for lba == 0 and consing up an appropriate 1542 * PMBR. 1543 */ 1544 if (efi.dki_lba < 1 || efi.dki_lba > 2 || length <= 0) 1545 return (SET_ERROR(EINVAL)); 1546 1547 gpe.efi_gpe_StartingLBA = LE_64(34ULL); 1548 gpe.efi_gpe_EndingLBA = LE_64((vs >> bs) - 1); 1549 UUID_LE_CONVERT(gpe.efi_gpe_PartitionTypeGUID, uuid); 1550 1551 if (efi.dki_lba == 1) { 1552 efi_gpt_t gpt = { 0 }; 1553 1554 gpt.efi_gpt_Signature = LE_64(EFI_SIGNATURE); 1555 gpt.efi_gpt_Revision = LE_32(EFI_VERSION_CURRENT); 1556 gpt.efi_gpt_HeaderSize = LE_32(sizeof (gpt)); 1557 gpt.efi_gpt_MyLBA = LE_64(1ULL); 1558 gpt.efi_gpt_FirstUsableLBA = LE_64(34ULL); 1559 gpt.efi_gpt_LastUsableLBA = LE_64((vs >> bs) - 1); 1560 gpt.efi_gpt_PartitionEntryLBA = LE_64(2ULL); 1561 gpt.efi_gpt_NumberOfPartitionEntries = LE_32(1); 1562 gpt.efi_gpt_SizeOfPartitionEntry = 1563 LE_32(sizeof (efi_gpe_t)); 1564 CRC32(crc, &gpe, sizeof (gpe), -1U, crc32_table); 1565 gpt.efi_gpt_PartitionEntryArrayCRC32 = LE_32(~crc); 1566 CRC32(crc, &gpt, sizeof (gpt), -1U, crc32_table); 1567 gpt.efi_gpt_HeaderCRC32 = LE_32(~crc); 1568 if (ddi_copyout(&gpt, ptr, MIN(sizeof (gpt), length), 1569 flag)) 1570 return (SET_ERROR(EFAULT)); 1571 ptr += sizeof (gpt); 1572 length -= sizeof (gpt); 1573 } 1574 if (length > 0 && ddi_copyout(&gpe, ptr, MIN(sizeof (gpe), 1575 length), flag)) 1576 return (SET_ERROR(EFAULT)); 1577 return (0); 1578} 1579 1580/* 1581 * BEGIN entry points to allow external callers access to the volume. 1582 */ 1583/* 1584 * Return the volume parameters needed for access from an external caller. 1585 * These values are invariant as long as the volume is held open. 1586 */ 1587int 1588zvol_get_volume_params(minor_t minor, uint64_t *blksize, 1589 uint64_t *max_xfer_len, void **minor_hdl, void **objset_hdl, void **zil_hdl, 1590 void **rl_hdl, void **bonus_hdl) 1591{ 1592 zvol_state_t *zv; 1593 1594 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1595 if (zv == NULL) 1596 return (SET_ERROR(ENXIO)); 1597 if (zv->zv_flags & ZVOL_DUMPIFIED) 1598 return (SET_ERROR(ENXIO)); 1599 1600 ASSERT(blksize && max_xfer_len && minor_hdl && 1601 objset_hdl && zil_hdl && rl_hdl && bonus_hdl); 1602 1603 *blksize = zv->zv_volblocksize; 1604 *max_xfer_len = (uint64_t)zvol_maxphys; 1605 *minor_hdl = zv; 1606 *objset_hdl = zv->zv_objset; 1607 *zil_hdl = zv->zv_zilog; 1608 *rl_hdl = &zv->zv_znode; 1609 *bonus_hdl = zv->zv_dbuf; 1610 return (0); 1611} 1612 1613/* 1614 * Return the current volume size to an external caller. 1615 * The size can change while the volume is open. 1616 */ 1617uint64_t 1618zvol_get_volume_size(void *minor_hdl) 1619{ 1620 zvol_state_t *zv = minor_hdl; 1621 1622 return (zv->zv_volsize); 1623} 1624 1625/* 1626 * Return the current WCE setting to an external caller. 1627 * The WCE setting can change while the volume is open. 1628 */ 1629int 1630zvol_get_volume_wce(void *minor_hdl) 1631{ 1632 zvol_state_t *zv = minor_hdl; 1633 1634 return ((zv->zv_flags & ZVOL_WCE) ? 1 : 0); 1635} 1636 1637/* 1638 * Entry point for external callers to zvol_log_write 1639 */ 1640void 1641zvol_log_write_minor(void *minor_hdl, dmu_tx_t *tx, offset_t off, ssize_t resid, 1642 boolean_t sync) 1643{ 1644 zvol_state_t *zv = minor_hdl; 1645 1646 zvol_log_write(zv, tx, off, resid, sync); 1647} 1648/* 1649 * END entry points to allow external callers access to the volume. 1650 */ 1651 1652/* 1653 * Dirtbag ioctls to support mkfs(1M) for UFS filesystems. See dkio(7I). 1654 */ 1655/*ARGSUSED*/ 1656int 1657zvol_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp) 1658{ 1659 zvol_state_t *zv; 1660 struct dk_cinfo dki; 1661 struct dk_minfo dkm; 1662 struct dk_callback *dkc; 1663 int error = 0; 1664 rl_t *rl; 1665 1666 mutex_enter(&spa_namespace_lock); 1667 1668 zv = zfsdev_get_soft_state(getminor(dev), ZSST_ZVOL); 1669 1670 if (zv == NULL) { 1671 mutex_exit(&spa_namespace_lock); 1672 return (SET_ERROR(ENXIO)); 1673 } 1674 ASSERT(zv->zv_total_opens > 0); 1675 1676 switch (cmd) { 1677 1678 case DKIOCINFO: 1679 bzero(&dki, sizeof (dki)); 1680 (void) strcpy(dki.dki_cname, "zvol"); 1681 (void) strcpy(dki.dki_dname, "zvol"); 1682 dki.dki_ctype = DKC_UNKNOWN; 1683 dki.dki_unit = getminor(dev); 1684 dki.dki_maxtransfer = 1 << (SPA_MAXBLOCKSHIFT - zv->zv_min_bs); 1685 mutex_exit(&spa_namespace_lock); 1686 if (ddi_copyout(&dki, (void *)arg, sizeof (dki), flag)) 1687 error = SET_ERROR(EFAULT); 1688 return (error); 1689 1690 case DKIOCGMEDIAINFO: 1691 bzero(&dkm, sizeof (dkm)); 1692 dkm.dki_lbsize = 1U << zv->zv_min_bs; 1693 dkm.dki_capacity = zv->zv_volsize >> zv->zv_min_bs; 1694 dkm.dki_media_type = DK_UNKNOWN; 1695 mutex_exit(&spa_namespace_lock); 1696 if (ddi_copyout(&dkm, (void *)arg, sizeof (dkm), flag)) 1697 error = SET_ERROR(EFAULT); 1698 return (error); 1699 1700 case DKIOCGETEFI: 1701 { 1702 uint64_t vs = zv->zv_volsize; 1703 uint8_t bs = zv->zv_min_bs; 1704 1705 mutex_exit(&spa_namespace_lock); 1706 error = zvol_getefi((void *)arg, flag, vs, bs); 1707 return (error); 1708 } 1709 1710 case DKIOCFLUSHWRITECACHE: 1711 dkc = (struct dk_callback *)arg; 1712 mutex_exit(&spa_namespace_lock); 1713 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1714 if ((flag & FKIOCTL) && dkc != NULL && dkc->dkc_callback) { 1715 (*dkc->dkc_callback)(dkc->dkc_cookie, error); 1716 error = 0; 1717 } 1718 return (error); 1719 1720 case DKIOCGETWCE: 1721 { 1722 int wce = (zv->zv_flags & ZVOL_WCE) ? 1 : 0; 1723 if (ddi_copyout(&wce, (void *)arg, sizeof (int), 1724 flag)) 1725 error = SET_ERROR(EFAULT); 1726 break; 1727 } 1728 case DKIOCSETWCE: 1729 { 1730 int wce; 1731 if (ddi_copyin((void *)arg, &wce, sizeof (int), 1732 flag)) { 1733 error = SET_ERROR(EFAULT); 1734 break; 1735 } 1736 if (wce) { 1737 zv->zv_flags |= ZVOL_WCE; 1738 mutex_exit(&spa_namespace_lock); 1739 } else { 1740 zv->zv_flags &= ~ZVOL_WCE; 1741 mutex_exit(&spa_namespace_lock); 1742 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1743 } 1744 return (0); 1745 } 1746 1747 case DKIOCGGEOM: 1748 case DKIOCGVTOC: 1749 /* 1750 * commands using these (like prtvtoc) expect ENOTSUP 1751 * since we're emulating an EFI label 1752 */ 1753 error = SET_ERROR(ENOTSUP); 1754 break; 1755 1756 case DKIOCDUMPINIT: 1757 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize, 1758 RL_WRITER); 1759 error = zvol_dumpify(zv); 1760 zfs_range_unlock(rl); 1761 break; 1762 1763 case DKIOCDUMPFINI: 1764 if (!(zv->zv_flags & ZVOL_DUMPIFIED)) 1765 break; 1766 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize, 1767 RL_WRITER); 1768 error = zvol_dump_fini(zv); 1769 zfs_range_unlock(rl); 1770 break; 1771 1772 case DKIOCFREE: 1773 { 1774 dkioc_free_t df; 1775 dmu_tx_t *tx; 1776 1777 if (ddi_copyin((void *)arg, &df, sizeof (df), flag)) { 1778 error = SET_ERROR(EFAULT); 1779 break; 1780 } 1781 1782 /* 1783 * Apply Postel's Law to length-checking. If they overshoot, 1784 * just blank out until the end, if there's a need to blank 1785 * out anything. 1786 */ 1787 if (df.df_start >= zv->zv_volsize) 1788 break; /* No need to do anything... */ 1789 if (df.df_start + df.df_length > zv->zv_volsize) 1790 df.df_length = DMU_OBJECT_END; 1791 1792 rl = zfs_range_lock(&zv->zv_znode, df.df_start, df.df_length, 1793 RL_WRITER); 1794 tx = dmu_tx_create(zv->zv_objset); 1795 error = dmu_tx_assign(tx, TXG_WAIT); 1796 if (error != 0) { 1797 dmu_tx_abort(tx); 1798 } else { 1799 zvol_log_truncate(zv, tx, df.df_start, 1800 df.df_length, B_TRUE); 1801 dmu_tx_commit(tx); 1802 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 1803 df.df_start, df.df_length); 1804 } 1805 1806 zfs_range_unlock(rl); 1807 1808 if (error == 0) { 1809 /* 1810 * If the write-cache is disabled or 'sync' property 1811 * is set to 'always' then treat this as a synchronous 1812 * operation (i.e. commit to zil). 1813 */ 1814 if (!(zv->zv_flags & ZVOL_WCE) || 1815 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)) 1816 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1817 1818 /* 1819 * If the caller really wants synchronous writes, and 1820 * can't wait for them, don't return until the write 1821 * is done. 1822 */ 1823 if (df.df_flags & DF_WAIT_SYNC) { 1824 txg_wait_synced( 1825 dmu_objset_pool(zv->zv_objset), 0); 1826 } 1827 } 1828 break; 1829 } 1830 1831 default: 1832 error = SET_ERROR(ENOTTY); 1833 break; 1834 1835 } 1836 mutex_exit(&spa_namespace_lock); 1837 return (error); 1838} 1839#endif /* sun */ 1840 1841int 1842zvol_busy(void) 1843{ 1844 return (zvol_minors != 0); 1845} 1846 1847void 1848zvol_init(void) 1849{ 1850 VERIFY(ddi_soft_state_init(&zfsdev_state, sizeof (zfs_soft_state_t), 1851 1) == 0); 1852 ZFS_LOG(1, "ZVOL Initialized."); 1853} 1854 1855void 1856zvol_fini(void) 1857{ 1858 ddi_soft_state_fini(&zfsdev_state); 1859 ZFS_LOG(1, "ZVOL Deinitialized."); 1860} 1861 1862#ifdef sun 1863/*ARGSUSED*/ 1864static int 1865zfs_mvdev_dump_feature_check(void *arg, dmu_tx_t *tx) 1866{ 1867 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 1868 1869 if (spa_feature_is_active(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP)) 1870 return (1); 1871 return (0); 1872} 1873 1874/*ARGSUSED*/ 1875static void 1876zfs_mvdev_dump_activate_feature_sync(void *arg, dmu_tx_t *tx) 1877{ 1878 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 1879 1880 spa_feature_incr(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP, tx); 1881} 1882 1883static int 1884zvol_dump_init(zvol_state_t *zv, boolean_t resize) 1885{ 1886 dmu_tx_t *tx; 1887 int error; 1888 objset_t *os = zv->zv_objset; 1889 spa_t *spa = dmu_objset_spa(os); 1890 vdev_t *vd = spa->spa_root_vdev; 1891 nvlist_t *nv = NULL; 1892 uint64_t version = spa_version(spa); 1893 enum zio_checksum checksum; 1894 1895 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 1896 ASSERT(vd->vdev_ops == &vdev_root_ops); 1897 1898 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 0, 1899 DMU_OBJECT_END); 1900 /* wait for dmu_free_long_range to actually free the blocks */ 1901 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 1902 1903 /* 1904 * If the pool on which the dump device is being initialized has more 1905 * than one child vdev, check that the MULTI_VDEV_CRASH_DUMP feature is 1906 * enabled. If so, bump that feature's counter to indicate that the 1907 * feature is active. We also check the vdev type to handle the 1908 * following case: 1909 * # zpool create test raidz disk1 disk2 disk3 1910 * Now have spa_root_vdev->vdev_children == 1 (the raidz vdev), 1911 * the raidz vdev itself has 3 children. 1912 */ 1913 if (vd->vdev_children > 1 || vd->vdev_ops == &vdev_raidz_ops) { 1914 if (!spa_feature_is_enabled(spa, 1915 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP)) 1916 return (SET_ERROR(ENOTSUP)); 1917 (void) dsl_sync_task(spa_name(spa), 1918 zfs_mvdev_dump_feature_check, 1919 zfs_mvdev_dump_activate_feature_sync, NULL, 2); 1920 } 1921 1922 tx = dmu_tx_create(os); 1923 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 1924 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 1925 error = dmu_tx_assign(tx, TXG_WAIT); 1926 if (error) { 1927 dmu_tx_abort(tx); 1928 return (error); 1929 } 1930 1931 /* 1932 * If MULTI_VDEV_CRASH_DUMP is active, use the NOPARITY checksum 1933 * function. Otherwise, use the old default -- OFF. 1934 */ 1935 checksum = spa_feature_is_active(spa, 1936 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP) ? ZIO_CHECKSUM_NOPARITY : 1937 ZIO_CHECKSUM_OFF; 1938 1939 /* 1940 * If we are resizing the dump device then we only need to 1941 * update the refreservation to match the newly updated 1942 * zvolsize. Otherwise, we save off the original state of the 1943 * zvol so that we can restore them if the zvol is ever undumpified. 1944 */ 1945 if (resize) { 1946 error = zap_update(os, ZVOL_ZAP_OBJ, 1947 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 1948 &zv->zv_volsize, tx); 1949 } else { 1950 uint64_t checksum, compress, refresrv, vbs, dedup; 1951 1952 error = dsl_prop_get_integer(zv->zv_name, 1953 zfs_prop_to_name(ZFS_PROP_COMPRESSION), &compress, NULL); 1954 error = error ? error : dsl_prop_get_integer(zv->zv_name, 1955 zfs_prop_to_name(ZFS_PROP_CHECKSUM), &checksum, NULL); 1956 error = error ? error : dsl_prop_get_integer(zv->zv_name, 1957 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &refresrv, NULL); 1958 error = error ? error : dsl_prop_get_integer(zv->zv_name, 1959 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &vbs, NULL); 1960 if (version >= SPA_VERSION_DEDUP) { 1961 error = error ? error : 1962 dsl_prop_get_integer(zv->zv_name, 1963 zfs_prop_to_name(ZFS_PROP_DEDUP), &dedup, NULL); 1964 } 1965 1966 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1967 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, 1968 &compress, tx); 1969 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1970 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum, tx); 1971 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1972 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 1973 &refresrv, tx); 1974 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1975 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, 1976 &vbs, tx); 1977 error = error ? error : dmu_object_set_blocksize( 1978 os, ZVOL_OBJ, SPA_MAXBLOCKSIZE, 0, tx); 1979 if (version >= SPA_VERSION_DEDUP) { 1980 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 1981 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, 1982 &dedup, tx); 1983 } 1984 if (error == 0) 1985 zv->zv_volblocksize = SPA_MAXBLOCKSIZE; 1986 } 1987 dmu_tx_commit(tx); 1988 1989 /* 1990 * We only need update the zvol's property if we are initializing 1991 * the dump area for the first time. 1992 */ 1993 if (!resize) { 1994 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 1995 VERIFY(nvlist_add_uint64(nv, 1996 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 0) == 0); 1997 VERIFY(nvlist_add_uint64(nv, 1998 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 1999 ZIO_COMPRESS_OFF) == 0); 2000 VERIFY(nvlist_add_uint64(nv, 2001 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 2002 checksum) == 0); 2003 if (version >= SPA_VERSION_DEDUP) { 2004 VERIFY(nvlist_add_uint64(nv, 2005 zfs_prop_to_name(ZFS_PROP_DEDUP), 2006 ZIO_CHECKSUM_OFF) == 0); 2007 } 2008 2009 error = zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL, 2010 nv, NULL); 2011 nvlist_free(nv); 2012 2013 if (error) 2014 return (error); 2015 } 2016 2017 /* Allocate the space for the dump */ 2018 error = zvol_prealloc(zv); 2019 return (error); 2020} 2021 2022static int 2023zvol_dumpify(zvol_state_t *zv) 2024{ 2025 int error = 0; 2026 uint64_t dumpsize = 0; 2027 dmu_tx_t *tx; 2028 objset_t *os = zv->zv_objset; 2029 2030 if (zv->zv_flags & ZVOL_RDONLY) 2031 return (SET_ERROR(EROFS)); 2032 2033 if (zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 2034 8, 1, &dumpsize) != 0 || dumpsize != zv->zv_volsize) { 2035 boolean_t resize = (dumpsize > 0); 2036 2037 if ((error = zvol_dump_init(zv, resize)) != 0) { 2038 (void) zvol_dump_fini(zv); 2039 return (error); 2040 } 2041 } 2042 2043 /* 2044 * Build up our lba mapping. 2045 */ 2046 error = zvol_get_lbas(zv); 2047 if (error) { 2048 (void) zvol_dump_fini(zv); 2049 return (error); 2050 } 2051 2052 tx = dmu_tx_create(os); 2053 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 2054 error = dmu_tx_assign(tx, TXG_WAIT); 2055 if (error) { 2056 dmu_tx_abort(tx); 2057 (void) zvol_dump_fini(zv); 2058 return (error); 2059 } 2060 2061 zv->zv_flags |= ZVOL_DUMPIFIED; 2062 error = zap_update(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 8, 1, 2063 &zv->zv_volsize, tx); 2064 dmu_tx_commit(tx); 2065 2066 if (error) { 2067 (void) zvol_dump_fini(zv); 2068 return (error); 2069 } 2070 2071 txg_wait_synced(dmu_objset_pool(os), 0); 2072 return (0); 2073} 2074 2075static int 2076zvol_dump_fini(zvol_state_t *zv) 2077{ 2078 dmu_tx_t *tx; 2079 objset_t *os = zv->zv_objset; 2080 nvlist_t *nv; 2081 int error = 0; 2082 uint64_t checksum, compress, refresrv, vbs, dedup; 2083 uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset)); 2084 2085 /* 2086 * Attempt to restore the zvol back to its pre-dumpified state. 2087 * This is a best-effort attempt as it's possible that not all 2088 * of these properties were initialized during the dumpify process 2089 * (i.e. error during zvol_dump_init). 2090 */ 2091 2092 tx = dmu_tx_create(os); 2093 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 2094 error = dmu_tx_assign(tx, TXG_WAIT); 2095 if (error) { 2096 dmu_tx_abort(tx); 2097 return (error); 2098 } 2099 (void) zap_remove(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, tx); 2100 dmu_tx_commit(tx); 2101 2102 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2103 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum); 2104 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2105 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, &compress); 2106 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2107 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, &refresrv); 2108 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2109 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, &vbs); 2110 2111 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 2112 (void) nvlist_add_uint64(nv, 2113 zfs_prop_to_name(ZFS_PROP_CHECKSUM), checksum); 2114 (void) nvlist_add_uint64(nv, 2115 zfs_prop_to_name(ZFS_PROP_COMPRESSION), compress); 2116 (void) nvlist_add_uint64(nv, 2117 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), refresrv); 2118 if (version >= SPA_VERSION_DEDUP && 2119 zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2120 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, &dedup) == 0) { 2121 (void) nvlist_add_uint64(nv, 2122 zfs_prop_to_name(ZFS_PROP_DEDUP), dedup); 2123 } 2124 (void) zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL, 2125 nv, NULL); 2126 nvlist_free(nv); 2127 2128 zvol_free_extents(zv); 2129 zv->zv_flags &= ~ZVOL_DUMPIFIED; 2130 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, DMU_OBJECT_END); 2131 /* wait for dmu_free_long_range to actually free the blocks */ 2132 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 2133 tx = dmu_tx_create(os); 2134 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 2135 error = dmu_tx_assign(tx, TXG_WAIT); 2136 if (error) { 2137 dmu_tx_abort(tx); 2138 return (error); 2139 } 2140 if (dmu_object_set_blocksize(os, ZVOL_OBJ, vbs, 0, tx) == 0) 2141 zv->zv_volblocksize = vbs; 2142 dmu_tx_commit(tx); 2143 2144 return (0); 2145} 2146#endif /* sun */ 2147 2148static zvol_state_t * 2149zvol_geom_create(const char *name) 2150{ 2151 struct g_provider *pp; 2152 struct g_geom *gp; 2153 zvol_state_t *zv; 2154 2155 gp = g_new_geomf(&zfs_zvol_class, "zfs::zvol::%s", name); 2156 gp->start = zvol_geom_start; 2157 gp->access = zvol_geom_access; 2158 pp = g_new_providerf(gp, "%s/%s", ZVOL_DRIVER, name); 2159 pp->flags |= G_PF_DIRECT_RECEIVE | G_PF_DIRECT_SEND; 2160 pp->sectorsize = DEV_BSIZE; 2161 2162 zv = kmem_zalloc(sizeof(*zv), KM_SLEEP); 2163 zv->zv_provider = pp; 2164 zv->zv_state = 0; 2165 bioq_init(&zv->zv_queue); 2166 mtx_init(&zv->zv_queue_mtx, "zvol", NULL, MTX_DEF); 2167 2168 pp->private = zv; 2169 2170 return (zv); 2171} 2172 2173static void 2174zvol_geom_run(zvol_state_t *zv) 2175{ 2176 struct g_provider *pp; 2177 2178 pp = zv->zv_provider; 2179 g_error_provider(pp, 0); 2180 2181 kproc_kthread_add(zvol_geom_worker, zv, &zfsproc, NULL, 0, 0, 2182 "zfskern", "zvol %s", pp->name + sizeof(ZVOL_DRIVER)); 2183} 2184 2185static void 2186zvol_geom_destroy(zvol_state_t *zv) 2187{ 2188 struct g_provider *pp; 2189 2190 g_topology_assert(); 2191 2192 mtx_lock(&zv->zv_queue_mtx); 2193 zv->zv_state = 1; 2194 wakeup_one(&zv->zv_queue); 2195 while (zv->zv_state != 2) 2196 msleep(&zv->zv_state, &zv->zv_queue_mtx, 0, "zvol:w", 0); 2197 mtx_destroy(&zv->zv_queue_mtx); 2198 2199 pp = zv->zv_provider; 2200 zv->zv_provider = NULL; 2201 pp->private = NULL; 2202 g_wither_geom(pp->geom, ENXIO); 2203 2204 kmem_free(zv, sizeof(*zv)); 2205} 2206 2207static int 2208zvol_geom_access(struct g_provider *pp, int acr, int acw, int ace) 2209{ 2210 int count, error, flags; 2211 2212 g_topology_assert(); 2213 2214 /* 2215 * To make it easier we expect either open or close, but not both 2216 * at the same time. 2217 */ 2218 KASSERT((acr >= 0 && acw >= 0 && ace >= 0) || 2219 (acr <= 0 && acw <= 0 && ace <= 0), 2220 ("Unsupported access request to %s (acr=%d, acw=%d, ace=%d).", 2221 pp->name, acr, acw, ace)); 2222 2223 if (pp->private == NULL) { 2224 if (acr <= 0 && acw <= 0 && ace <= 0) 2225 return (0); 2226 return (pp->error); 2227 } 2228 2229 /* 2230 * We don't pass FEXCL flag to zvol_open()/zvol_close() if ace != 0, 2231 * because GEOM already handles that and handles it a bit differently. 2232 * GEOM allows for multiple read/exclusive consumers and ZFS allows 2233 * only one exclusive consumer, no matter if it is reader or writer. 2234 * I like better the way GEOM works so I'll leave it for GEOM to 2235 * decide what to do. 2236 */ 2237 2238 count = acr + acw + ace; 2239 if (count == 0) 2240 return (0); 2241 2242 flags = 0; 2243 if (acr != 0 || ace != 0) 2244 flags |= FREAD; 2245 if (acw != 0) 2246 flags |= FWRITE; 2247 2248 g_topology_unlock(); 2249 if (count > 0) 2250 error = zvol_open(pp, flags, count); 2251 else 2252 error = zvol_close(pp, flags, -count); 2253 g_topology_lock(); 2254 return (error); 2255} 2256 2257static void 2258zvol_geom_start(struct bio *bp) 2259{ 2260 zvol_state_t *zv; 2261 boolean_t first; 2262 2263 zv = bp->bio_to->private; 2264 ASSERT(zv != NULL); 2265 switch (bp->bio_cmd) { 2266 case BIO_FLUSH: 2267 if (!THREAD_CAN_SLEEP()) 2268 goto enqueue; 2269 zil_commit(zv->zv_zilog, ZVOL_OBJ); 2270 g_io_deliver(bp, 0); 2271 break; 2272 case BIO_READ: 2273 case BIO_WRITE: 2274 if (!THREAD_CAN_SLEEP()) 2275 goto enqueue; 2276 zvol_strategy(bp); 2277 break; 2278 case BIO_GETATTR: 2279 case BIO_DELETE: 2280 default: 2281 g_io_deliver(bp, EOPNOTSUPP); 2282 break; 2283 } 2284 return; 2285 2286enqueue: 2287 mtx_lock(&zv->zv_queue_mtx); 2288 first = (bioq_first(&zv->zv_queue) == NULL); 2289 bioq_insert_tail(&zv->zv_queue, bp); 2290 mtx_unlock(&zv->zv_queue_mtx); 2291 if (first) 2292 wakeup_one(&zv->zv_queue); 2293} 2294 2295static void 2296zvol_geom_worker(void *arg) 2297{ 2298 zvol_state_t *zv; 2299 struct bio *bp; 2300 2301 thread_lock(curthread); 2302 sched_prio(curthread, PRIBIO); 2303 thread_unlock(curthread); 2304 2305 zv = arg; 2306 for (;;) { 2307 mtx_lock(&zv->zv_queue_mtx); 2308 bp = bioq_takefirst(&zv->zv_queue); 2309 if (bp == NULL) { 2310 if (zv->zv_state == 1) { 2311 zv->zv_state = 2; 2312 wakeup(&zv->zv_state); 2313 mtx_unlock(&zv->zv_queue_mtx); 2314 kthread_exit(); 2315 } 2316 msleep(&zv->zv_queue, &zv->zv_queue_mtx, PRIBIO | PDROP, 2317 "zvol:io", 0); 2318 continue; 2319 } 2320 mtx_unlock(&zv->zv_queue_mtx); 2321 switch (bp->bio_cmd) { 2322 case BIO_FLUSH: 2323 zil_commit(zv->zv_zilog, ZVOL_OBJ); 2324 g_io_deliver(bp, 0); 2325 break; 2326 case BIO_READ: 2327 case BIO_WRITE: 2328 zvol_strategy(bp); 2329 break; 2330 } 2331 } 2332} 2333 2334extern boolean_t dataset_name_hidden(const char *name); 2335 2336static int 2337zvol_create_snapshots(objset_t *os, const char *name) 2338{ 2339 uint64_t cookie, obj; 2340 char *sname; 2341 int error, len; 2342 2343 cookie = obj = 0; 2344 sname = kmem_alloc(MAXPATHLEN, KM_SLEEP); 2345 2346#if 0 2347 (void) dmu_objset_find(name, dmu_objset_prefetch, NULL, 2348 DS_FIND_SNAPSHOTS); 2349#endif 2350 2351 for (;;) { 2352 len = snprintf(sname, MAXPATHLEN, "%s@", name); 2353 if (len >= MAXPATHLEN) { 2354 dmu_objset_rele(os, FTAG); 2355 error = ENAMETOOLONG; 2356 break; 2357 } 2358 2359 dsl_pool_config_enter(dmu_objset_pool(os), FTAG); 2360 error = dmu_snapshot_list_next(os, MAXPATHLEN - len, 2361 sname + len, &obj, &cookie, NULL); 2362 dsl_pool_config_exit(dmu_objset_pool(os), FTAG); 2363 if (error != 0) { 2364 if (error == ENOENT) 2365 error = 0; 2366 break; 2367 } 2368 2369 if ((error = zvol_create_minor(sname)) != 0) { 2370 printf("ZFS WARNING: Unable to create ZVOL %s (error=%d).\n", 2371 sname, error); 2372 break; 2373 } 2374 } 2375 2376 kmem_free(sname, MAXPATHLEN); 2377 return (error); 2378} 2379 2380int 2381zvol_create_minors(const char *name) 2382{ 2383 uint64_t cookie; 2384 objset_t *os; 2385 char *osname, *p; 2386 int error, len; 2387 2388 if (dataset_name_hidden(name)) 2389 return (0); 2390 2391 if ((error = dmu_objset_hold(name, FTAG, &os)) != 0) { 2392 printf("ZFS WARNING: Unable to put hold on %s (error=%d).\n", 2393 name, error); 2394 return (error); 2395 } 2396 if (dmu_objset_type(os) == DMU_OST_ZVOL) { 2397 dsl_dataset_long_hold(os->os_dsl_dataset, FTAG); 2398 dsl_pool_rele(dmu_objset_pool(os), FTAG); 2399 if ((error = zvol_create_minor(name)) == 0) 2400 error = zvol_create_snapshots(os, name); 2401 else { 2402 printf("ZFS WARNING: Unable to create ZVOL %s (error=%d).\n", 2403 name, error); 2404 } 2405 dsl_dataset_long_rele(os->os_dsl_dataset, FTAG); 2406 dsl_dataset_rele(os->os_dsl_dataset, FTAG); 2407 return (error); 2408 } 2409 if (dmu_objset_type(os) != DMU_OST_ZFS) { 2410 dmu_objset_rele(os, FTAG); 2411 return (0); 2412 } 2413 2414 osname = kmem_alloc(MAXPATHLEN, KM_SLEEP); 2415 if (snprintf(osname, MAXPATHLEN, "%s/", name) >= MAXPATHLEN) { 2416 dmu_objset_rele(os, FTAG); 2417 kmem_free(osname, MAXPATHLEN); 2418 return (ENOENT); 2419 } 2420 p = osname + strlen(osname); 2421 len = MAXPATHLEN - (p - osname); 2422 2423#if 0 2424 /* Prefetch the datasets. */ 2425 cookie = 0; 2426 while (dmu_dir_list_next(os, len, p, NULL, &cookie) == 0) { 2427 if (!dataset_name_hidden(osname)) 2428 (void) dmu_objset_prefetch(osname, NULL); 2429 } 2430#endif 2431 2432 cookie = 0; 2433 while (dmu_dir_list_next(os, MAXPATHLEN - (p - osname), p, NULL, 2434 &cookie) == 0) { 2435 dmu_objset_rele(os, FTAG); 2436 (void)zvol_create_minors(osname); 2437 if ((error = dmu_objset_hold(name, FTAG, &os)) != 0) { 2438 printf("ZFS WARNING: Unable to put hold on %s (error=%d).\n", 2439 name, error); 2440 return (error); 2441 } 2442 } 2443 2444 dmu_objset_rele(os, FTAG); 2445 kmem_free(osname, MAXPATHLEN); 2446 return (0); 2447} 2448 2449static void 2450zvol_rename_minor(struct g_geom *gp, const char *newname) 2451{ 2452 struct g_provider *pp; 2453 zvol_state_t *zv; 2454 2455 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 2456 g_topology_assert(); 2457 2458 pp = LIST_FIRST(&gp->provider); 2459 ASSERT(pp != NULL); 2460 zv = pp->private; 2461 ASSERT(zv != NULL); 2462 2463 zv->zv_provider = NULL; 2464 g_wither_provider(pp, ENXIO); 2465 2466 pp = g_new_providerf(gp, "%s/%s", ZVOL_DRIVER, newname); 2467 pp->flags |= G_PF_DIRECT_RECEIVE | G_PF_DIRECT_SEND; 2468 pp->sectorsize = DEV_BSIZE; 2469 pp->mediasize = zv->zv_volsize; 2470 pp->private = zv; 2471 zv->zv_provider = pp; 2472 strlcpy(zv->zv_name, newname, sizeof(zv->zv_name)); 2473 g_error_provider(pp, 0); 2474} 2475 2476void 2477zvol_rename_minors(const char *oldname, const char *newname) 2478{ 2479 char name[MAXPATHLEN]; 2480 struct g_provider *pp; 2481 struct g_geom *gp; 2482 size_t oldnamelen, newnamelen; 2483 zvol_state_t *zv; 2484 char *namebuf; 2485 2486 oldnamelen = strlen(oldname); 2487 newnamelen = strlen(newname); 2488 2489 DROP_GIANT(); 2490 mutex_enter(&spa_namespace_lock); 2491 g_topology_lock(); 2492 2493 LIST_FOREACH(gp, &zfs_zvol_class.geom, geom) { 2494 pp = LIST_FIRST(&gp->provider); 2495 if (pp == NULL) 2496 continue; 2497 zv = pp->private; 2498 if (zv == NULL) 2499 continue; 2500 if (strcmp(zv->zv_name, oldname) == 0) { 2501 zvol_rename_minor(gp, newname); 2502 } else if (strncmp(zv->zv_name, oldname, oldnamelen) == 0 && 2503 (zv->zv_name[oldnamelen] == '/' || 2504 zv->zv_name[oldnamelen] == '@')) { 2505 snprintf(name, sizeof(name), "%s%c%s", newname, 2506 zv->zv_name[oldnamelen], 2507 zv->zv_name + oldnamelen + 1); 2508 zvol_rename_minor(gp, name); 2509 } 2510 } 2511 2512 g_topology_unlock(); 2513 mutex_exit(&spa_namespace_lock); 2514 PICKUP_GIANT(); 2515} 2516