zvol.c revision 269006
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 * 27 * Portions Copyright 2010 Robert Milkowski 28 * 29 * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 30 * Copyright (c) 2012, 2014 by Delphix. All rights reserved. 31 * Copyright (c) 2013, Joyent, Inc. All rights reserved. 32 */ 33 34/* Portions Copyright 2011 Martin Matuska <mm@FreeBSD.org> */ 35 36/* 37 * ZFS volume emulation driver. 38 * 39 * Makes a DMU object look like a volume of arbitrary size, up to 2^64 bytes. 40 * Volumes are accessed through the symbolic links named: 41 * 42 * /dev/zvol/dsk/<pool_name>/<dataset_name> 43 * /dev/zvol/rdsk/<pool_name>/<dataset_name> 44 * 45 * These links are created by the /dev filesystem (sdev_zvolops.c). 46 * Volumes are persistent through reboot. No user command needs to be 47 * run before opening and using a device. 48 * 49 * FreeBSD notes. 50 * On FreeBSD ZVOLs are simply GEOM providers like any other storage device 51 * in the system. 52 */ 53 54#include <sys/types.h> 55#include <sys/param.h> 56#include <sys/kernel.h> 57#include <sys/errno.h> 58#include <sys/uio.h> 59#include <sys/bio.h> 60#include <sys/buf.h> 61#include <sys/kmem.h> 62#include <sys/conf.h> 63#include <sys/cmn_err.h> 64#include <sys/stat.h> 65#include <sys/zap.h> 66#include <sys/spa.h> 67#include <sys/spa_impl.h> 68#include <sys/zio.h> 69#include <sys/disk.h> 70#include <sys/dmu_traverse.h> 71#include <sys/dnode.h> 72#include <sys/dsl_dataset.h> 73#include <sys/dsl_prop.h> 74#include <sys/dkio.h> 75#include <sys/byteorder.h> 76#include <sys/sunddi.h> 77#include <sys/dirent.h> 78#include <sys/policy.h> 79#include <sys/queue.h> 80#include <sys/fs/zfs.h> 81#include <sys/zfs_ioctl.h> 82#include <sys/zil.h> 83#include <sys/refcount.h> 84#include <sys/zfs_znode.h> 85#include <sys/zfs_rlock.h> 86#include <sys/vdev_impl.h> 87#include <sys/vdev_raidz.h> 88#include <sys/zvol.h> 89#include <sys/zil_impl.h> 90#include <sys/dbuf.h> 91#include <sys/dmu_tx.h> 92#include <sys/zfeature.h> 93#include <sys/zio_checksum.h> 94 95#include <geom/geom.h> 96 97#include "zfs_namecheck.h" 98 99struct g_class zfs_zvol_class = { 100 .name = "ZFS::ZVOL", 101 .version = G_VERSION, 102}; 103 104DECLARE_GEOM_CLASS(zfs_zvol_class, zfs_zvol); 105 106void *zfsdev_state; 107static char *zvol_tag = "zvol_tag"; 108 109#define ZVOL_DUMPSIZE "dumpsize" 110 111/* 112 * The spa_namespace_lock protects the zfsdev_state structure from being 113 * modified while it's being used, e.g. an open that comes in before a 114 * create finishes. It also protects temporary opens of the dataset so that, 115 * e.g., an open doesn't get a spurious EBUSY. 116 */ 117static uint32_t zvol_minors; 118 119SYSCTL_DECL(_vfs_zfs); 120SYSCTL_NODE(_vfs_zfs, OID_AUTO, vol, CTLFLAG_RW, 0, "ZFS VOLUME"); 121static int volmode = ZFS_VOLMODE_GEOM; 122TUNABLE_INT("vfs.zfs.vol.mode", &volmode); 123SYSCTL_INT(_vfs_zfs_vol, OID_AUTO, mode, CTLFLAG_RWTUN, &volmode, 0, 124 "Expose as GEOM providers (1), device files (2) or neither"); 125 126typedef struct zvol_extent { 127 list_node_t ze_node; 128 dva_t ze_dva; /* dva associated with this extent */ 129 uint64_t ze_nblks; /* number of blocks in extent */ 130} zvol_extent_t; 131 132/* 133 * The in-core state of each volume. 134 */ 135typedef struct zvol_state { 136 LIST_ENTRY(zvol_state) zv_links; 137 char zv_name[MAXPATHLEN]; /* pool/dd name */ 138 uint64_t zv_volsize; /* amount of space we advertise */ 139 uint64_t zv_volblocksize; /* volume block size */ 140 struct cdev *zv_dev; /* non-GEOM device */ 141 struct g_provider *zv_provider; /* GEOM provider */ 142 uint8_t zv_min_bs; /* minimum addressable block shift */ 143 uint8_t zv_flags; /* readonly, dumpified, etc. */ 144 objset_t *zv_objset; /* objset handle */ 145 uint32_t zv_total_opens; /* total open count */ 146 zilog_t *zv_zilog; /* ZIL handle */ 147 list_t zv_extents; /* List of extents for dump */ 148 znode_t zv_znode; /* for range locking */ 149 dmu_buf_t *zv_dbuf; /* bonus handle */ 150 int zv_state; 151 int zv_volmode; /* Provide GEOM or cdev */ 152 struct bio_queue_head zv_queue; 153 struct mtx zv_queue_mtx; /* zv_queue mutex */ 154} zvol_state_t; 155 156static LIST_HEAD(, zvol_state) all_zvols; 157 158/* 159 * zvol specific flags 160 */ 161#define ZVOL_RDONLY 0x1 162#define ZVOL_DUMPIFIED 0x2 163#define ZVOL_EXCL 0x4 164#define ZVOL_WCE 0x8 165 166/* 167 * zvol maximum transfer in one DMU tx. 168 */ 169int zvol_maxphys = DMU_MAX_ACCESS/2; 170 171static d_open_t zvol_d_open; 172static d_close_t zvol_d_close; 173static d_read_t zvol_read; 174static d_write_t zvol_write; 175static d_ioctl_t zvol_d_ioctl; 176static d_strategy_t zvol_strategy; 177 178static struct cdevsw zvol_cdevsw = { 179 .d_version = D_VERSION, 180 .d_open = zvol_d_open, 181 .d_close = zvol_d_close, 182 .d_read = zvol_read, 183 .d_write = zvol_write, 184 .d_ioctl = zvol_d_ioctl, 185 .d_strategy = zvol_strategy, 186 .d_name = "zvol", 187 .d_flags = D_DISK | D_TRACKCLOSE, 188}; 189 190extern int zfs_set_prop_nvlist(const char *, zprop_source_t, 191 nvlist_t *, nvlist_t *); 192static void zvol_log_truncate(zvol_state_t *zv, dmu_tx_t *tx, uint64_t off, 193 uint64_t len, boolean_t sync); 194static int zvol_remove_zv(zvol_state_t *); 195static int zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio); 196static int zvol_dumpify(zvol_state_t *zv); 197static int zvol_dump_fini(zvol_state_t *zv); 198static int zvol_dump_init(zvol_state_t *zv, boolean_t resize); 199 200static void zvol_geom_run(zvol_state_t *zv); 201static void zvol_geom_destroy(zvol_state_t *zv); 202static int zvol_geom_access(struct g_provider *pp, int acr, int acw, int ace); 203static void zvol_geom_start(struct bio *bp); 204static void zvol_geom_worker(void *arg); 205 206static void 207zvol_size_changed(zvol_state_t *zv) 208{ 209#ifdef sun 210 dev_t dev = makedevice(maj, min); 211 212 VERIFY(ddi_prop_update_int64(dev, zfs_dip, 213 "Size", volsize) == DDI_SUCCESS); 214 VERIFY(ddi_prop_update_int64(dev, zfs_dip, 215 "Nblocks", lbtodb(volsize)) == DDI_SUCCESS); 216 217 /* Notify specfs to invalidate the cached size */ 218 spec_size_invalidate(dev, VBLK); 219 spec_size_invalidate(dev, VCHR); 220#else /* !sun */ 221 if (zv->zv_volmode == ZFS_VOLMODE_GEOM) { 222 struct g_provider *pp; 223 224 pp = zv->zv_provider; 225 if (pp == NULL) 226 return; 227 g_topology_lock(); 228 g_resize_provider(pp, zv->zv_volsize); 229 g_topology_unlock(); 230 } 231#endif /* !sun */ 232} 233 234int 235zvol_check_volsize(uint64_t volsize, uint64_t blocksize) 236{ 237 if (volsize == 0) 238 return (SET_ERROR(EINVAL)); 239 240 if (volsize % blocksize != 0) 241 return (SET_ERROR(EINVAL)); 242 243#ifdef _ILP32 244 if (volsize - 1 > SPEC_MAXOFFSET_T) 245 return (SET_ERROR(EOVERFLOW)); 246#endif 247 return (0); 248} 249 250int 251zvol_check_volblocksize(uint64_t volblocksize) 252{ 253 if (volblocksize < SPA_MINBLOCKSIZE || 254 volblocksize > SPA_MAXBLOCKSIZE || 255 !ISP2(volblocksize)) 256 return (SET_ERROR(EDOM)); 257 258 return (0); 259} 260 261int 262zvol_get_stats(objset_t *os, nvlist_t *nv) 263{ 264 int error; 265 dmu_object_info_t doi; 266 uint64_t val; 267 268 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val); 269 if (error) 270 return (error); 271 272 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val); 273 274 error = dmu_object_info(os, ZVOL_OBJ, &doi); 275 276 if (error == 0) { 277 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE, 278 doi.doi_data_block_size); 279 } 280 281 return (error); 282} 283 284static zvol_state_t * 285zvol_minor_lookup(const char *name) 286{ 287 zvol_state_t *zv; 288 289 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 290 291 LIST_FOREACH(zv, &all_zvols, zv_links) { 292 if (strcmp(zv->zv_name, name) == 0) 293 break; 294 } 295 296 return (zv); 297} 298 299/* extent mapping arg */ 300struct maparg { 301 zvol_state_t *ma_zv; 302 uint64_t ma_blks; 303}; 304 305/*ARGSUSED*/ 306static int 307zvol_map_block(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, 308 const zbookmark_phys_t *zb, const dnode_phys_t *dnp, void *arg) 309{ 310 struct maparg *ma = arg; 311 zvol_extent_t *ze; 312 int bs = ma->ma_zv->zv_volblocksize; 313 314 if (BP_IS_HOLE(bp) || 315 zb->zb_object != ZVOL_OBJ || zb->zb_level != 0) 316 return (0); 317 318 VERIFY(!BP_IS_EMBEDDED(bp)); 319 320 VERIFY3U(ma->ma_blks, ==, zb->zb_blkid); 321 ma->ma_blks++; 322 323 /* Abort immediately if we have encountered gang blocks */ 324 if (BP_IS_GANG(bp)) 325 return (SET_ERROR(EFRAGS)); 326 327 /* 328 * See if the block is at the end of the previous extent. 329 */ 330 ze = list_tail(&ma->ma_zv->zv_extents); 331 if (ze && 332 DVA_GET_VDEV(BP_IDENTITY(bp)) == DVA_GET_VDEV(&ze->ze_dva) && 333 DVA_GET_OFFSET(BP_IDENTITY(bp)) == 334 DVA_GET_OFFSET(&ze->ze_dva) + ze->ze_nblks * bs) { 335 ze->ze_nblks++; 336 return (0); 337 } 338 339 dprintf_bp(bp, "%s", "next blkptr:"); 340 341 /* start a new extent */ 342 ze = kmem_zalloc(sizeof (zvol_extent_t), KM_SLEEP); 343 ze->ze_dva = bp->blk_dva[0]; /* structure assignment */ 344 ze->ze_nblks = 1; 345 list_insert_tail(&ma->ma_zv->zv_extents, ze); 346 return (0); 347} 348 349static void 350zvol_free_extents(zvol_state_t *zv) 351{ 352 zvol_extent_t *ze; 353 354 while (ze = list_head(&zv->zv_extents)) { 355 list_remove(&zv->zv_extents, ze); 356 kmem_free(ze, sizeof (zvol_extent_t)); 357 } 358} 359 360static int 361zvol_get_lbas(zvol_state_t *zv) 362{ 363 objset_t *os = zv->zv_objset; 364 struct maparg ma; 365 int err; 366 367 ma.ma_zv = zv; 368 ma.ma_blks = 0; 369 zvol_free_extents(zv); 370 371 /* commit any in-flight changes before traversing the dataset */ 372 txg_wait_synced(dmu_objset_pool(os), 0); 373 err = traverse_dataset(dmu_objset_ds(os), 0, 374 TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA, zvol_map_block, &ma); 375 if (err || ma.ma_blks != (zv->zv_volsize / zv->zv_volblocksize)) { 376 zvol_free_extents(zv); 377 return (err ? err : EIO); 378 } 379 380 return (0); 381} 382 383/* ARGSUSED */ 384void 385zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx) 386{ 387 zfs_creat_t *zct = arg; 388 nvlist_t *nvprops = zct->zct_props; 389 int error; 390 uint64_t volblocksize, volsize; 391 392 VERIFY(nvlist_lookup_uint64(nvprops, 393 zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0); 394 if (nvlist_lookup_uint64(nvprops, 395 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0) 396 volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE); 397 398 /* 399 * These properties must be removed from the list so the generic 400 * property setting step won't apply to them. 401 */ 402 VERIFY(nvlist_remove_all(nvprops, 403 zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0); 404 (void) nvlist_remove_all(nvprops, 405 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE)); 406 407 error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize, 408 DMU_OT_NONE, 0, tx); 409 ASSERT(error == 0); 410 411 error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP, 412 DMU_OT_NONE, 0, tx); 413 ASSERT(error == 0); 414 415 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx); 416 ASSERT(error == 0); 417} 418 419/* 420 * Replay a TX_TRUNCATE ZIL transaction if asked. TX_TRUNCATE is how we 421 * implement DKIOCFREE/free-long-range. 422 */ 423static int 424zvol_replay_truncate(zvol_state_t *zv, lr_truncate_t *lr, boolean_t byteswap) 425{ 426 uint64_t offset, length; 427 428 if (byteswap) 429 byteswap_uint64_array(lr, sizeof (*lr)); 430 431 offset = lr->lr_offset; 432 length = lr->lr_length; 433 434 return (dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, offset, length)); 435} 436 437/* 438 * Replay a TX_WRITE ZIL transaction that didn't get committed 439 * after a system failure 440 */ 441static int 442zvol_replay_write(zvol_state_t *zv, lr_write_t *lr, boolean_t byteswap) 443{ 444 objset_t *os = zv->zv_objset; 445 char *data = (char *)(lr + 1); /* data follows lr_write_t */ 446 uint64_t offset, length; 447 dmu_tx_t *tx; 448 int error; 449 450 if (byteswap) 451 byteswap_uint64_array(lr, sizeof (*lr)); 452 453 offset = lr->lr_offset; 454 length = lr->lr_length; 455 456 /* If it's a dmu_sync() block, write the whole block */ 457 if (lr->lr_common.lrc_reclen == sizeof (lr_write_t)) { 458 uint64_t blocksize = BP_GET_LSIZE(&lr->lr_blkptr); 459 if (length < blocksize) { 460 offset -= offset % blocksize; 461 length = blocksize; 462 } 463 } 464 465 tx = dmu_tx_create(os); 466 dmu_tx_hold_write(tx, ZVOL_OBJ, offset, length); 467 error = dmu_tx_assign(tx, TXG_WAIT); 468 if (error) { 469 dmu_tx_abort(tx); 470 } else { 471 dmu_write(os, ZVOL_OBJ, offset, length, data, tx); 472 dmu_tx_commit(tx); 473 } 474 475 return (error); 476} 477 478/* ARGSUSED */ 479static int 480zvol_replay_err(zvol_state_t *zv, lr_t *lr, boolean_t byteswap) 481{ 482 return (SET_ERROR(ENOTSUP)); 483} 484 485/* 486 * Callback vectors for replaying records. 487 * Only TX_WRITE and TX_TRUNCATE are needed for zvol. 488 */ 489zil_replay_func_t *zvol_replay_vector[TX_MAX_TYPE] = { 490 zvol_replay_err, /* 0 no such transaction type */ 491 zvol_replay_err, /* TX_CREATE */ 492 zvol_replay_err, /* TX_MKDIR */ 493 zvol_replay_err, /* TX_MKXATTR */ 494 zvol_replay_err, /* TX_SYMLINK */ 495 zvol_replay_err, /* TX_REMOVE */ 496 zvol_replay_err, /* TX_RMDIR */ 497 zvol_replay_err, /* TX_LINK */ 498 zvol_replay_err, /* TX_RENAME */ 499 zvol_replay_write, /* TX_WRITE */ 500 zvol_replay_truncate, /* TX_TRUNCATE */ 501 zvol_replay_err, /* TX_SETATTR */ 502 zvol_replay_err, /* TX_ACL */ 503 zvol_replay_err, /* TX_CREATE_ACL */ 504 zvol_replay_err, /* TX_CREATE_ATTR */ 505 zvol_replay_err, /* TX_CREATE_ACL_ATTR */ 506 zvol_replay_err, /* TX_MKDIR_ACL */ 507 zvol_replay_err, /* TX_MKDIR_ATTR */ 508 zvol_replay_err, /* TX_MKDIR_ACL_ATTR */ 509 zvol_replay_err, /* TX_WRITE2 */ 510}; 511 512#ifdef sun 513int 514zvol_name2minor(const char *name, minor_t *minor) 515{ 516 zvol_state_t *zv; 517 518 mutex_enter(&spa_namespace_lock); 519 zv = zvol_minor_lookup(name); 520 if (minor && zv) 521 *minor = zv->zv_minor; 522 mutex_exit(&spa_namespace_lock); 523 return (zv ? 0 : -1); 524} 525#endif /* sun */ 526 527/* 528 * Create a minor node (plus a whole lot more) for the specified volume. 529 */ 530int 531zvol_create_minor(const char *name) 532{ 533 zfs_soft_state_t *zs; 534 zvol_state_t *zv; 535 objset_t *os; 536 struct cdev *dev; 537 struct g_provider *pp; 538 struct g_geom *gp; 539 dmu_object_info_t doi; 540 uint64_t volsize, mode; 541 int error; 542 543 ZFS_LOG(1, "Creating ZVOL %s...", name); 544 545 mutex_enter(&spa_namespace_lock); 546 547 if (zvol_minor_lookup(name) != NULL) { 548 mutex_exit(&spa_namespace_lock); 549 return (SET_ERROR(EEXIST)); 550 } 551 552 /* lie and say we're read-only */ 553 error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, FTAG, &os); 554 555 if (error) { 556 mutex_exit(&spa_namespace_lock); 557 return (error); 558 } 559 560#ifdef sun 561 if ((minor = zfsdev_minor_alloc()) == 0) { 562 dmu_objset_disown(os, FTAG); 563 mutex_exit(&spa_namespace_lock); 564 return (SET_ERROR(ENXIO)); 565 } 566 567 if (ddi_soft_state_zalloc(zfsdev_state, minor) != DDI_SUCCESS) { 568 dmu_objset_disown(os, FTAG); 569 mutex_exit(&spa_namespace_lock); 570 return (SET_ERROR(EAGAIN)); 571 } 572 (void) ddi_prop_update_string(minor, zfs_dip, ZVOL_PROP_NAME, 573 (char *)name); 574 575 (void) snprintf(chrbuf, sizeof (chrbuf), "%u,raw", minor); 576 577 if (ddi_create_minor_node(zfs_dip, chrbuf, S_IFCHR, 578 minor, DDI_PSEUDO, 0) == DDI_FAILURE) { 579 ddi_soft_state_free(zfsdev_state, minor); 580 dmu_objset_disown(os, FTAG); 581 mutex_exit(&spa_namespace_lock); 582 return (SET_ERROR(EAGAIN)); 583 } 584 585 (void) snprintf(blkbuf, sizeof (blkbuf), "%u", minor); 586 587 if (ddi_create_minor_node(zfs_dip, blkbuf, S_IFBLK, 588 minor, DDI_PSEUDO, 0) == DDI_FAILURE) { 589 ddi_remove_minor_node(zfs_dip, chrbuf); 590 ddi_soft_state_free(zfsdev_state, minor); 591 dmu_objset_disown(os, FTAG); 592 mutex_exit(&spa_namespace_lock); 593 return (SET_ERROR(EAGAIN)); 594 } 595 596 zs = ddi_get_soft_state(zfsdev_state, minor); 597 zs->zss_type = ZSST_ZVOL; 598 zv = zs->zss_data = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP); 599#else /* !sun */ 600 601 zv = kmem_zalloc(sizeof(*zv), KM_SLEEP); 602 zv->zv_state = 0; 603 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize); 604 if (error) { 605 kmem_free(zv, sizeof(*zv)); 606 dmu_objset_disown(os, zvol_tag); 607 mutex_exit(&spa_namespace_lock); 608 return (error); 609 } 610 error = dsl_prop_get_integer(name, 611 zfs_prop_to_name(ZFS_PROP_VOLMODE), &mode, NULL); 612 if (error != 0 || mode == ZFS_VOLMODE_DEFAULT) 613 mode = volmode; 614 615 DROP_GIANT(); 616 zv->zv_volsize = volsize; 617 zv->zv_volmode = mode; 618 if (zv->zv_volmode == ZFS_VOLMODE_GEOM) { 619 g_topology_lock(); 620 gp = g_new_geomf(&zfs_zvol_class, "zfs::zvol::%s", name); 621 gp->start = zvol_geom_start; 622 gp->access = zvol_geom_access; 623 pp = g_new_providerf(gp, "%s/%s", ZVOL_DRIVER, name); 624 pp->flags |= G_PF_DIRECT_RECEIVE | G_PF_DIRECT_SEND; 625 pp->sectorsize = DEV_BSIZE; 626 pp->mediasize = zv->zv_volsize; 627 pp->private = zv; 628 629 zv->zv_provider = pp; 630 bioq_init(&zv->zv_queue); 631 mtx_init(&zv->zv_queue_mtx, "zvol", NULL, MTX_DEF); 632 } else if (zv->zv_volmode == ZFS_VOLMODE_DEV) { 633 if (make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK, 634 &dev, &zvol_cdevsw, NULL, UID_ROOT, GID_OPERATOR, 635 0640, "%s/%s", ZVOL_DRIVER, name) != 0) { 636 kmem_free(zv, sizeof(*zv)); 637 dmu_objset_disown(os, FTAG); 638 mutex_exit(&spa_namespace_lock); 639 return (SET_ERROR(ENXIO)); 640 } 641 zv->zv_dev = dev; 642 dev->si_iosize_max = MAXPHYS; 643 dev->si_drv2 = zv; 644 } 645 LIST_INSERT_HEAD(&all_zvols, zv, zv_links); 646#endif /* !sun */ 647 648 (void) strlcpy(zv->zv_name, name, MAXPATHLEN); 649 zv->zv_min_bs = DEV_BSHIFT; 650 zv->zv_objset = os; 651 if (dmu_objset_is_snapshot(os) || !spa_writeable(dmu_objset_spa(os))) 652 zv->zv_flags |= ZVOL_RDONLY; 653 mutex_init(&zv->zv_znode.z_range_lock, NULL, MUTEX_DEFAULT, NULL); 654 avl_create(&zv->zv_znode.z_range_avl, zfs_range_compare, 655 sizeof (rl_t), offsetof(rl_t, r_node)); 656 list_create(&zv->zv_extents, sizeof (zvol_extent_t), 657 offsetof(zvol_extent_t, ze_node)); 658 /* get and cache the blocksize */ 659 error = dmu_object_info(os, ZVOL_OBJ, &doi); 660 ASSERT(error == 0); 661 zv->zv_volblocksize = doi.doi_data_block_size; 662 663 if (spa_writeable(dmu_objset_spa(os))) { 664 if (zil_replay_disable) 665 zil_destroy(dmu_objset_zil(os), B_FALSE); 666 else 667 zil_replay(os, zv, zvol_replay_vector); 668 } 669 dmu_objset_disown(os, FTAG); 670 zv->zv_objset = NULL; 671 672 zvol_minors++; 673 674 mutex_exit(&spa_namespace_lock); 675 676#ifndef sun 677 if (zv->zv_volmode == ZFS_VOLMODE_GEOM) { 678 zvol_geom_run(zv); 679 g_topology_unlock(); 680 } 681 PICKUP_GIANT(); 682#endif 683 684 ZFS_LOG(1, "ZVOL %s created.", name); 685 686 return (0); 687} 688 689/* 690 * Remove minor node for the specified volume. 691 */ 692static int 693zvol_remove_zv(zvol_state_t *zv) 694{ 695#ifdef sun 696 minor_t minor = zv->zv_minor; 697#endif 698 699 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 700 if (zv->zv_total_opens != 0) 701 return (SET_ERROR(EBUSY)); 702 703 ZFS_LOG(1, "ZVOL %s destroyed.", zv->zv_name); 704 705#ifdef sun 706 (void) snprintf(nmbuf, sizeof (nmbuf), "%u,raw", minor); 707 ddi_remove_minor_node(zfs_dip, nmbuf); 708#else 709 LIST_REMOVE(zv, zv_links); 710 if (zv->zv_volmode == ZFS_VOLMODE_GEOM) { 711 g_topology_lock(); 712 zvol_geom_destroy(zv); 713 g_topology_unlock(); 714 } else if (zv->zv_volmode == ZFS_VOLMODE_DEV) 715 destroy_dev(zv->zv_dev); 716#endif /* sun */ 717 718 avl_destroy(&zv->zv_znode.z_range_avl); 719 mutex_destroy(&zv->zv_znode.z_range_lock); 720 721 kmem_free(zv, sizeof(*zv)); 722 723 zvol_minors--; 724 return (0); 725} 726 727int 728zvol_remove_minor(const char *name) 729{ 730 zvol_state_t *zv; 731 int rc; 732 733 mutex_enter(&spa_namespace_lock); 734 if ((zv = zvol_minor_lookup(name)) == NULL) { 735 mutex_exit(&spa_namespace_lock); 736 return (SET_ERROR(ENXIO)); 737 } 738 rc = zvol_remove_zv(zv); 739 mutex_exit(&spa_namespace_lock); 740 return (rc); 741} 742 743int 744zvol_first_open(zvol_state_t *zv) 745{ 746 objset_t *os; 747 uint64_t volsize; 748 int error; 749 uint64_t readonly; 750 751 /* lie and say we're read-only */ 752 error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, B_TRUE, 753 zvol_tag, &os); 754 if (error) 755 return (error); 756 757 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize); 758 if (error) { 759 ASSERT(error == 0); 760 dmu_objset_disown(os, zvol_tag); 761 return (error); 762 } 763 zv->zv_objset = os; 764 error = dmu_bonus_hold(os, ZVOL_OBJ, zvol_tag, &zv->zv_dbuf); 765 if (error) { 766 dmu_objset_disown(os, zvol_tag); 767 return (error); 768 } 769 zv->zv_volsize = volsize; 770 zv->zv_zilog = zil_open(os, zvol_get_data); 771 zvol_size_changed(zv); 772 773 VERIFY(dsl_prop_get_integer(zv->zv_name, "readonly", &readonly, 774 NULL) == 0); 775 if (readonly || dmu_objset_is_snapshot(os) || 776 !spa_writeable(dmu_objset_spa(os))) 777 zv->zv_flags |= ZVOL_RDONLY; 778 else 779 zv->zv_flags &= ~ZVOL_RDONLY; 780 return (error); 781} 782 783void 784zvol_last_close(zvol_state_t *zv) 785{ 786 zil_close(zv->zv_zilog); 787 zv->zv_zilog = NULL; 788 789 dmu_buf_rele(zv->zv_dbuf, zvol_tag); 790 zv->zv_dbuf = NULL; 791 792 /* 793 * Evict cached data 794 */ 795 if (dsl_dataset_is_dirty(dmu_objset_ds(zv->zv_objset)) && 796 !(zv->zv_flags & ZVOL_RDONLY)) 797 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 798 dmu_objset_evict_dbufs(zv->zv_objset); 799 800 dmu_objset_disown(zv->zv_objset, zvol_tag); 801 zv->zv_objset = NULL; 802} 803 804#ifdef sun 805int 806zvol_prealloc(zvol_state_t *zv) 807{ 808 objset_t *os = zv->zv_objset; 809 dmu_tx_t *tx; 810 uint64_t refd, avail, usedobjs, availobjs; 811 uint64_t resid = zv->zv_volsize; 812 uint64_t off = 0; 813 814 /* Check the space usage before attempting to allocate the space */ 815 dmu_objset_space(os, &refd, &avail, &usedobjs, &availobjs); 816 if (avail < zv->zv_volsize) 817 return (SET_ERROR(ENOSPC)); 818 819 /* Free old extents if they exist */ 820 zvol_free_extents(zv); 821 822 while (resid != 0) { 823 int error; 824 uint64_t bytes = MIN(resid, SPA_MAXBLOCKSIZE); 825 826 tx = dmu_tx_create(os); 827 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes); 828 error = dmu_tx_assign(tx, TXG_WAIT); 829 if (error) { 830 dmu_tx_abort(tx); 831 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, off); 832 return (error); 833 } 834 dmu_prealloc(os, ZVOL_OBJ, off, bytes, tx); 835 dmu_tx_commit(tx); 836 off += bytes; 837 resid -= bytes; 838 } 839 txg_wait_synced(dmu_objset_pool(os), 0); 840 841 return (0); 842} 843#endif /* sun */ 844 845static int 846zvol_update_volsize(objset_t *os, uint64_t volsize) 847{ 848 dmu_tx_t *tx; 849 int error; 850 851 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 852 853 tx = dmu_tx_create(os); 854 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 855 dmu_tx_mark_netfree(tx); 856 error = dmu_tx_assign(tx, TXG_WAIT); 857 if (error) { 858 dmu_tx_abort(tx); 859 return (error); 860 } 861 862 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, 863 &volsize, tx); 864 dmu_tx_commit(tx); 865 866 if (error == 0) 867 error = dmu_free_long_range(os, 868 ZVOL_OBJ, volsize, DMU_OBJECT_END); 869 return (error); 870} 871 872void 873zvol_remove_minors(const char *name) 874{ 875 zvol_state_t *zv, *tzv; 876 size_t namelen; 877 878 namelen = strlen(name); 879 880 DROP_GIANT(); 881 mutex_enter(&spa_namespace_lock); 882 883 LIST_FOREACH_SAFE(zv, &all_zvols, zv_links, tzv) { 884 if (strcmp(zv->zv_name, name) == 0 || 885 (strncmp(zv->zv_name, name, namelen) == 0 && 886 zv->zv_name[namelen] == '/')) { 887 (void) zvol_remove_zv(zv); 888 } 889 } 890 891 mutex_exit(&spa_namespace_lock); 892 PICKUP_GIANT(); 893} 894 895int 896zvol_set_volsize(const char *name, major_t maj, uint64_t volsize) 897{ 898 zvol_state_t *zv = NULL; 899 objset_t *os; 900 int error; 901 dmu_object_info_t doi; 902 uint64_t old_volsize = 0ULL; 903 uint64_t readonly; 904 905 mutex_enter(&spa_namespace_lock); 906 zv = zvol_minor_lookup(name); 907 if ((error = dmu_objset_hold(name, FTAG, &os)) != 0) { 908 mutex_exit(&spa_namespace_lock); 909 return (error); 910 } 911 912 if ((error = dmu_object_info(os, ZVOL_OBJ, &doi)) != 0 || 913 (error = zvol_check_volsize(volsize, 914 doi.doi_data_block_size)) != 0) 915 goto out; 916 917 VERIFY(dsl_prop_get_integer(name, "readonly", &readonly, 918 NULL) == 0); 919 if (readonly) { 920 error = EROFS; 921 goto out; 922 } 923 924 error = zvol_update_volsize(os, volsize); 925 /* 926 * Reinitialize the dump area to the new size. If we 927 * failed to resize the dump area then restore it back to 928 * its original size. 929 */ 930 if (zv && error == 0) { 931#ifdef ZVOL_DUMP 932 if (zv->zv_flags & ZVOL_DUMPIFIED) { 933 old_volsize = zv->zv_volsize; 934 zv->zv_volsize = volsize; 935 if ((error = zvol_dumpify(zv)) != 0 || 936 (error = dumpvp_resize()) != 0) { 937 (void) zvol_update_volsize(os, old_volsize); 938 zv->zv_volsize = old_volsize; 939 error = zvol_dumpify(zv); 940 } 941 } 942#endif /* ZVOL_DUMP */ 943 if (error == 0) { 944 zv->zv_volsize = volsize; 945 zvol_size_changed(zv); 946 } 947 } 948 949#ifdef sun 950 /* 951 * Generate a LUN expansion event. 952 */ 953 if (zv && error == 0) { 954 sysevent_id_t eid; 955 nvlist_t *attr; 956 char *physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 957 958 (void) snprintf(physpath, MAXPATHLEN, "%s%u", ZVOL_PSEUDO_DEV, 959 zv->zv_minor); 960 961 VERIFY(nvlist_alloc(&attr, NV_UNIQUE_NAME, KM_SLEEP) == 0); 962 VERIFY(nvlist_add_string(attr, DEV_PHYS_PATH, physpath) == 0); 963 964 (void) ddi_log_sysevent(zfs_dip, SUNW_VENDOR, EC_DEV_STATUS, 965 ESC_DEV_DLE, attr, &eid, DDI_SLEEP); 966 967 nvlist_free(attr); 968 kmem_free(physpath, MAXPATHLEN); 969 } 970#endif /* sun */ 971 972out: 973 dmu_objset_rele(os, FTAG); 974 975 mutex_exit(&spa_namespace_lock); 976 977 return (error); 978} 979 980/*ARGSUSED*/ 981static int 982zvol_open(struct g_provider *pp, int flag, int count) 983{ 984 zvol_state_t *zv; 985 int err = 0; 986 boolean_t locked = B_FALSE; 987 988 /* 989 * Protect against recursively entering spa_namespace_lock 990 * when spa_open() is used for a pool on a (local) ZVOL(s). 991 * This is needed since we replaced upstream zfsdev_state_lock 992 * with spa_namespace_lock in the ZVOL code. 993 * We are using the same trick as spa_open(). 994 * Note that calls in zvol_first_open which need to resolve 995 * pool name to a spa object will enter spa_open() 996 * recursively, but that function already has all the 997 * necessary protection. 998 */ 999 if (!MUTEX_HELD(&spa_namespace_lock)) { 1000 mutex_enter(&spa_namespace_lock); 1001 locked = B_TRUE; 1002 } 1003 1004 zv = pp->private; 1005 if (zv == NULL) { 1006 if (locked) 1007 mutex_exit(&spa_namespace_lock); 1008 return (SET_ERROR(ENXIO)); 1009 } 1010 1011 if (zv->zv_total_opens == 0) { 1012 err = zvol_first_open(zv); 1013 if (err) { 1014 if (locked) 1015 mutex_exit(&spa_namespace_lock); 1016 return (err); 1017 } 1018 pp->mediasize = zv->zv_volsize; 1019 pp->stripeoffset = 0; 1020 pp->stripesize = zv->zv_volblocksize; 1021 } 1022 if ((flag & FWRITE) && (zv->zv_flags & ZVOL_RDONLY)) { 1023 err = SET_ERROR(EROFS); 1024 goto out; 1025 } 1026 if (zv->zv_flags & ZVOL_EXCL) { 1027 err = SET_ERROR(EBUSY); 1028 goto out; 1029 } 1030#ifdef FEXCL 1031 if (flag & FEXCL) { 1032 if (zv->zv_total_opens != 0) { 1033 err = SET_ERROR(EBUSY); 1034 goto out; 1035 } 1036 zv->zv_flags |= ZVOL_EXCL; 1037 } 1038#endif 1039 1040 zv->zv_total_opens += count; 1041 if (locked) 1042 mutex_exit(&spa_namespace_lock); 1043 1044 return (err); 1045out: 1046 if (zv->zv_total_opens == 0) 1047 zvol_last_close(zv); 1048 if (locked) 1049 mutex_exit(&spa_namespace_lock); 1050 return (err); 1051} 1052 1053/*ARGSUSED*/ 1054static int 1055zvol_close(struct g_provider *pp, int flag, int count) 1056{ 1057 zvol_state_t *zv; 1058 int error = 0; 1059 boolean_t locked = B_FALSE; 1060 1061 /* See comment in zvol_open(). */ 1062 if (!MUTEX_HELD(&spa_namespace_lock)) { 1063 mutex_enter(&spa_namespace_lock); 1064 locked = B_TRUE; 1065 } 1066 1067 zv = pp->private; 1068 if (zv == NULL) { 1069 if (locked) 1070 mutex_exit(&spa_namespace_lock); 1071 return (SET_ERROR(ENXIO)); 1072 } 1073 1074 if (zv->zv_flags & ZVOL_EXCL) { 1075 ASSERT(zv->zv_total_opens == 1); 1076 zv->zv_flags &= ~ZVOL_EXCL; 1077 } 1078 1079 /* 1080 * If the open count is zero, this is a spurious close. 1081 * That indicates a bug in the kernel / DDI framework. 1082 */ 1083 ASSERT(zv->zv_total_opens != 0); 1084 1085 /* 1086 * You may get multiple opens, but only one close. 1087 */ 1088 zv->zv_total_opens -= count; 1089 1090 if (zv->zv_total_opens == 0) 1091 zvol_last_close(zv); 1092 1093 if (locked) 1094 mutex_exit(&spa_namespace_lock); 1095 return (error); 1096} 1097 1098static void 1099zvol_get_done(zgd_t *zgd, int error) 1100{ 1101 if (zgd->zgd_db) 1102 dmu_buf_rele(zgd->zgd_db, zgd); 1103 1104 zfs_range_unlock(zgd->zgd_rl); 1105 1106 if (error == 0 && zgd->zgd_bp) 1107 zil_add_block(zgd->zgd_zilog, zgd->zgd_bp); 1108 1109 kmem_free(zgd, sizeof (zgd_t)); 1110} 1111 1112/* 1113 * Get data to generate a TX_WRITE intent log record. 1114 */ 1115static int 1116zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio) 1117{ 1118 zvol_state_t *zv = arg; 1119 objset_t *os = zv->zv_objset; 1120 uint64_t object = ZVOL_OBJ; 1121 uint64_t offset = lr->lr_offset; 1122 uint64_t size = lr->lr_length; /* length of user data */ 1123 blkptr_t *bp = &lr->lr_blkptr; 1124 dmu_buf_t *db; 1125 zgd_t *zgd; 1126 int error; 1127 1128 ASSERT(zio != NULL); 1129 ASSERT(size != 0); 1130 1131 zgd = kmem_zalloc(sizeof (zgd_t), KM_SLEEP); 1132 zgd->zgd_zilog = zv->zv_zilog; 1133 zgd->zgd_rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER); 1134 1135 /* 1136 * Write records come in two flavors: immediate and indirect. 1137 * For small writes it's cheaper to store the data with the 1138 * log record (immediate); for large writes it's cheaper to 1139 * sync the data and get a pointer to it (indirect) so that 1140 * we don't have to write the data twice. 1141 */ 1142 if (buf != NULL) { /* immediate write */ 1143 error = dmu_read(os, object, offset, size, buf, 1144 DMU_READ_NO_PREFETCH); 1145 } else { 1146 size = zv->zv_volblocksize; 1147 offset = P2ALIGN(offset, size); 1148 error = dmu_buf_hold(os, object, offset, zgd, &db, 1149 DMU_READ_NO_PREFETCH); 1150 if (error == 0) { 1151 blkptr_t *obp = dmu_buf_get_blkptr(db); 1152 if (obp) { 1153 ASSERT(BP_IS_HOLE(bp)); 1154 *bp = *obp; 1155 } 1156 1157 zgd->zgd_db = db; 1158 zgd->zgd_bp = bp; 1159 1160 ASSERT(db->db_offset == offset); 1161 ASSERT(db->db_size == size); 1162 1163 error = dmu_sync(zio, lr->lr_common.lrc_txg, 1164 zvol_get_done, zgd); 1165 1166 if (error == 0) 1167 return (0); 1168 } 1169 } 1170 1171 zvol_get_done(zgd, error); 1172 1173 return (error); 1174} 1175 1176/* 1177 * zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions. 1178 * 1179 * We store data in the log buffers if it's small enough. 1180 * Otherwise we will later flush the data out via dmu_sync(). 1181 */ 1182ssize_t zvol_immediate_write_sz = 32768; 1183 1184static void 1185zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, offset_t off, ssize_t resid, 1186 boolean_t sync) 1187{ 1188 uint32_t blocksize = zv->zv_volblocksize; 1189 zilog_t *zilog = zv->zv_zilog; 1190 boolean_t slogging; 1191 ssize_t immediate_write_sz; 1192 1193 if (zil_replaying(zilog, tx)) 1194 return; 1195 1196 immediate_write_sz = (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT) 1197 ? 0 : zvol_immediate_write_sz; 1198 1199 slogging = spa_has_slogs(zilog->zl_spa) && 1200 (zilog->zl_logbias == ZFS_LOGBIAS_LATENCY); 1201 1202 while (resid) { 1203 itx_t *itx; 1204 lr_write_t *lr; 1205 ssize_t len; 1206 itx_wr_state_t write_state; 1207 1208 /* 1209 * Unlike zfs_log_write() we can be called with 1210 * upto DMU_MAX_ACCESS/2 (5MB) writes. 1211 */ 1212 if (blocksize > immediate_write_sz && !slogging && 1213 resid >= blocksize && off % blocksize == 0) { 1214 write_state = WR_INDIRECT; /* uses dmu_sync */ 1215 len = blocksize; 1216 } else if (sync) { 1217 write_state = WR_COPIED; 1218 len = MIN(ZIL_MAX_LOG_DATA, resid); 1219 } else { 1220 write_state = WR_NEED_COPY; 1221 len = MIN(ZIL_MAX_LOG_DATA, resid); 1222 } 1223 1224 itx = zil_itx_create(TX_WRITE, sizeof (*lr) + 1225 (write_state == WR_COPIED ? len : 0)); 1226 lr = (lr_write_t *)&itx->itx_lr; 1227 if (write_state == WR_COPIED && dmu_read(zv->zv_objset, 1228 ZVOL_OBJ, off, len, lr + 1, DMU_READ_NO_PREFETCH) != 0) { 1229 zil_itx_destroy(itx); 1230 itx = zil_itx_create(TX_WRITE, sizeof (*lr)); 1231 lr = (lr_write_t *)&itx->itx_lr; 1232 write_state = WR_NEED_COPY; 1233 } 1234 1235 itx->itx_wr_state = write_state; 1236 if (write_state == WR_NEED_COPY) 1237 itx->itx_sod += len; 1238 lr->lr_foid = ZVOL_OBJ; 1239 lr->lr_offset = off; 1240 lr->lr_length = len; 1241 lr->lr_blkoff = 0; 1242 BP_ZERO(&lr->lr_blkptr); 1243 1244 itx->itx_private = zv; 1245 itx->itx_sync = sync; 1246 1247 zil_itx_assign(zilog, itx, tx); 1248 1249 off += len; 1250 resid -= len; 1251 } 1252} 1253 1254#ifdef sun 1255static int 1256zvol_dumpio_vdev(vdev_t *vd, void *addr, uint64_t offset, uint64_t origoffset, 1257 uint64_t size, boolean_t doread, boolean_t isdump) 1258{ 1259 vdev_disk_t *dvd; 1260 int c; 1261 int numerrors = 0; 1262 1263 if (vd->vdev_ops == &vdev_mirror_ops || 1264 vd->vdev_ops == &vdev_replacing_ops || 1265 vd->vdev_ops == &vdev_spare_ops) { 1266 for (c = 0; c < vd->vdev_children; c++) { 1267 int err = zvol_dumpio_vdev(vd->vdev_child[c], 1268 addr, offset, origoffset, size, doread, isdump); 1269 if (err != 0) { 1270 numerrors++; 1271 } else if (doread) { 1272 break; 1273 } 1274 } 1275 } 1276 1277 if (!vd->vdev_ops->vdev_op_leaf && vd->vdev_ops != &vdev_raidz_ops) 1278 return (numerrors < vd->vdev_children ? 0 : EIO); 1279 1280 if (doread && !vdev_readable(vd)) 1281 return (SET_ERROR(EIO)); 1282 else if (!doread && !vdev_writeable(vd)) 1283 return (SET_ERROR(EIO)); 1284 1285 if (vd->vdev_ops == &vdev_raidz_ops) { 1286 return (vdev_raidz_physio(vd, 1287 addr, size, offset, origoffset, doread, isdump)); 1288 } 1289 1290 offset += VDEV_LABEL_START_SIZE; 1291 1292 if (ddi_in_panic() || isdump) { 1293 ASSERT(!doread); 1294 if (doread) 1295 return (SET_ERROR(EIO)); 1296 dvd = vd->vdev_tsd; 1297 ASSERT3P(dvd, !=, NULL); 1298 return (ldi_dump(dvd->vd_lh, addr, lbtodb(offset), 1299 lbtodb(size))); 1300 } else { 1301 dvd = vd->vdev_tsd; 1302 ASSERT3P(dvd, !=, NULL); 1303 return (vdev_disk_ldi_physio(dvd->vd_lh, addr, size, 1304 offset, doread ? B_READ : B_WRITE)); 1305 } 1306} 1307 1308static int 1309zvol_dumpio(zvol_state_t *zv, void *addr, uint64_t offset, uint64_t size, 1310 boolean_t doread, boolean_t isdump) 1311{ 1312 vdev_t *vd; 1313 int error; 1314 zvol_extent_t *ze; 1315 spa_t *spa = dmu_objset_spa(zv->zv_objset); 1316 1317 /* Must be sector aligned, and not stradle a block boundary. */ 1318 if (P2PHASE(offset, DEV_BSIZE) || P2PHASE(size, DEV_BSIZE) || 1319 P2BOUNDARY(offset, size, zv->zv_volblocksize)) { 1320 return (SET_ERROR(EINVAL)); 1321 } 1322 ASSERT(size <= zv->zv_volblocksize); 1323 1324 /* Locate the extent this belongs to */ 1325 ze = list_head(&zv->zv_extents); 1326 while (offset >= ze->ze_nblks * zv->zv_volblocksize) { 1327 offset -= ze->ze_nblks * zv->zv_volblocksize; 1328 ze = list_next(&zv->zv_extents, ze); 1329 } 1330 1331 if (ze == NULL) 1332 return (SET_ERROR(EINVAL)); 1333 1334 if (!ddi_in_panic()) 1335 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER); 1336 1337 vd = vdev_lookup_top(spa, DVA_GET_VDEV(&ze->ze_dva)); 1338 offset += DVA_GET_OFFSET(&ze->ze_dva); 1339 error = zvol_dumpio_vdev(vd, addr, offset, DVA_GET_OFFSET(&ze->ze_dva), 1340 size, doread, isdump); 1341 1342 if (!ddi_in_panic()) 1343 spa_config_exit(spa, SCL_STATE, FTAG); 1344 1345 return (error); 1346} 1347#endif /* sun */ 1348 1349void 1350zvol_strategy(struct bio *bp) 1351{ 1352 zvol_state_t *zv; 1353 uint64_t off, volsize; 1354 size_t resid; 1355 char *addr; 1356 objset_t *os; 1357 rl_t *rl; 1358 int error = 0; 1359 boolean_t doread = 0; 1360 boolean_t is_dumpified; 1361 boolean_t sync; 1362 1363 if (bp->bio_to) 1364 zv = bp->bio_to->private; 1365 else 1366 zv = bp->bio_dev->si_drv2; 1367 1368 if (zv == NULL) { 1369 error = ENXIO; 1370 goto out; 1371 } 1372 1373 if (bp->bio_cmd != BIO_READ && (zv->zv_flags & ZVOL_RDONLY)) { 1374 error = EROFS; 1375 goto out; 1376 } 1377 1378 switch (bp->bio_cmd) { 1379 case BIO_FLUSH: 1380 goto sync; 1381 case BIO_READ: 1382 doread = 1; 1383 case BIO_WRITE: 1384 case BIO_DELETE: 1385 break; 1386 default: 1387 error = EOPNOTSUPP; 1388 goto out; 1389 } 1390 1391 off = bp->bio_offset; 1392 volsize = zv->zv_volsize; 1393 1394 os = zv->zv_objset; 1395 ASSERT(os != NULL); 1396 1397 addr = bp->bio_data; 1398 resid = bp->bio_length; 1399 1400 if (resid > 0 && (off < 0 || off >= volsize)) { 1401 error = EIO; 1402 goto out; 1403 } 1404 1405#ifdef illumos 1406 is_dumpified = zv->zv_flags & ZVOL_DUMPIFIED; 1407#else 1408 is_dumpified = B_FALSE; 1409#endif 1410 sync = !doread && !is_dumpified && 1411 zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS; 1412 1413 /* 1414 * There must be no buffer changes when doing a dmu_sync() because 1415 * we can't change the data whilst calculating the checksum. 1416 */ 1417 rl = zfs_range_lock(&zv->zv_znode, off, resid, 1418 doread ? RL_READER : RL_WRITER); 1419 1420 if (bp->bio_cmd == BIO_DELETE) { 1421 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset); 1422 error = dmu_tx_assign(tx, TXG_WAIT); 1423 if (error != 0) { 1424 dmu_tx_abort(tx); 1425 } else { 1426 zvol_log_truncate(zv, tx, off, resid, B_TRUE); 1427 dmu_tx_commit(tx); 1428 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 1429 off, resid); 1430 resid = 0; 1431 } 1432 goto unlock; 1433 } 1434 1435 while (resid != 0 && off < volsize) { 1436 size_t size = MIN(resid, zvol_maxphys); 1437#ifdef illumos 1438 if (is_dumpified) { 1439 size = MIN(size, P2END(off, zv->zv_volblocksize) - off); 1440 error = zvol_dumpio(zv, addr, off, size, 1441 doread, B_FALSE); 1442 } else if (doread) { 1443#else 1444 if (doread) { 1445#endif 1446 error = dmu_read(os, ZVOL_OBJ, off, size, addr, 1447 DMU_READ_PREFETCH); 1448 } else { 1449 dmu_tx_t *tx = dmu_tx_create(os); 1450 dmu_tx_hold_write(tx, ZVOL_OBJ, off, size); 1451 error = dmu_tx_assign(tx, TXG_WAIT); 1452 if (error) { 1453 dmu_tx_abort(tx); 1454 } else { 1455 dmu_write(os, ZVOL_OBJ, off, size, addr, tx); 1456 zvol_log_write(zv, tx, off, size, sync); 1457 dmu_tx_commit(tx); 1458 } 1459 } 1460 if (error) { 1461 /* convert checksum errors into IO errors */ 1462 if (error == ECKSUM) 1463 error = SET_ERROR(EIO); 1464 break; 1465 } 1466 off += size; 1467 addr += size; 1468 resid -= size; 1469 } 1470unlock: 1471 zfs_range_unlock(rl); 1472 1473 bp->bio_completed = bp->bio_length - resid; 1474 if (bp->bio_completed < bp->bio_length && off > volsize) 1475 error = EINVAL; 1476 1477 if (sync) { 1478sync: 1479 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1480 } 1481out: 1482 if (bp->bio_to) 1483 g_io_deliver(bp, error); 1484 else 1485 biofinish(bp, NULL, error); 1486} 1487 1488#ifdef sun 1489/* 1490 * Set the buffer count to the zvol maximum transfer. 1491 * Using our own routine instead of the default minphys() 1492 * means that for larger writes we write bigger buffers on X86 1493 * (128K instead of 56K) and flush the disk write cache less often 1494 * (every zvol_maxphys - currently 1MB) instead of minphys (currently 1495 * 56K on X86 and 128K on sparc). 1496 */ 1497void 1498zvol_minphys(struct buf *bp) 1499{ 1500 if (bp->b_bcount > zvol_maxphys) 1501 bp->b_bcount = zvol_maxphys; 1502} 1503 1504int 1505zvol_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblocks) 1506{ 1507 minor_t minor = getminor(dev); 1508 zvol_state_t *zv; 1509 int error = 0; 1510 uint64_t size; 1511 uint64_t boff; 1512 uint64_t resid; 1513 1514 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1515 if (zv == NULL) 1516 return (SET_ERROR(ENXIO)); 1517 1518 if ((zv->zv_flags & ZVOL_DUMPIFIED) == 0) 1519 return (SET_ERROR(EINVAL)); 1520 1521 boff = ldbtob(blkno); 1522 resid = ldbtob(nblocks); 1523 1524 VERIFY3U(boff + resid, <=, zv->zv_volsize); 1525 1526 while (resid) { 1527 size = MIN(resid, P2END(boff, zv->zv_volblocksize) - boff); 1528 error = zvol_dumpio(zv, addr, boff, size, B_FALSE, B_TRUE); 1529 if (error) 1530 break; 1531 boff += size; 1532 addr += size; 1533 resid -= size; 1534 } 1535 1536 return (error); 1537} 1538 1539/*ARGSUSED*/ 1540int 1541zvol_read(dev_t dev, uio_t *uio, cred_t *cr) 1542{ 1543 minor_t minor = getminor(dev); 1544#else 1545int 1546zvol_read(struct cdev *dev, struct uio *uio, int ioflag) 1547{ 1548#endif 1549 zvol_state_t *zv; 1550 uint64_t volsize; 1551 rl_t *rl; 1552 int error = 0; 1553 1554#ifdef sun 1555 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1556 if (zv == NULL) 1557 return (SET_ERROR(ENXIO)); 1558#else 1559 zv = dev->si_drv2; 1560#endif 1561 1562 volsize = zv->zv_volsize; 1563 if (uio->uio_resid > 0 && 1564 (uio->uio_loffset < 0 || uio->uio_loffset > volsize)) 1565 return (SET_ERROR(EIO)); 1566 1567#ifdef illumos 1568 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1569 error = physio(zvol_strategy, NULL, dev, B_READ, 1570 zvol_minphys, uio); 1571 return (error); 1572 } 1573#endif 1574 1575 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid, 1576 RL_READER); 1577 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1578 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1579 1580 /* don't read past the end */ 1581 if (bytes > volsize - uio->uio_loffset) 1582 bytes = volsize - uio->uio_loffset; 1583 1584 error = dmu_read_uio(zv->zv_objset, ZVOL_OBJ, uio, bytes); 1585 if (error) { 1586 /* convert checksum errors into IO errors */ 1587 if (error == ECKSUM) 1588 error = SET_ERROR(EIO); 1589 break; 1590 } 1591 } 1592 zfs_range_unlock(rl); 1593 return (error); 1594} 1595 1596#ifdef sun 1597/*ARGSUSED*/ 1598int 1599zvol_write(dev_t dev, uio_t *uio, cred_t *cr) 1600{ 1601 minor_t minor = getminor(dev); 1602#else 1603int 1604zvol_write(struct cdev *dev, struct uio *uio, int ioflag) 1605{ 1606#endif 1607 zvol_state_t *zv; 1608 uint64_t volsize; 1609 rl_t *rl; 1610 int error = 0; 1611 boolean_t sync; 1612 1613#ifdef sun 1614 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1615 if (zv == NULL) 1616 return (SET_ERROR(ENXIO)); 1617#else 1618 zv = dev->si_drv2; 1619#endif 1620 1621 volsize = zv->zv_volsize; 1622 if (uio->uio_resid > 0 && 1623 (uio->uio_loffset < 0 || uio->uio_loffset > volsize)) 1624 return (SET_ERROR(EIO)); 1625 1626#ifdef illumos 1627 if (zv->zv_flags & ZVOL_DUMPIFIED) { 1628 error = physio(zvol_strategy, NULL, dev, B_WRITE, 1629 zvol_minphys, uio); 1630 return (error); 1631 } 1632#endif 1633 1634#ifdef sun 1635 sync = !(zv->zv_flags & ZVOL_WCE) || 1636#else 1637 sync = 1638#endif 1639 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS); 1640 1641 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid, 1642 RL_WRITER); 1643 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) { 1644 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1); 1645 uint64_t off = uio->uio_loffset; 1646 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset); 1647 1648 if (bytes > volsize - off) /* don't write past the end */ 1649 bytes = volsize - off; 1650 1651 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes); 1652 error = dmu_tx_assign(tx, TXG_WAIT); 1653 if (error) { 1654 dmu_tx_abort(tx); 1655 break; 1656 } 1657 error = dmu_write_uio_dbuf(zv->zv_dbuf, uio, bytes, tx); 1658 if (error == 0) 1659 zvol_log_write(zv, tx, off, bytes, sync); 1660 dmu_tx_commit(tx); 1661 1662 if (error) 1663 break; 1664 } 1665 zfs_range_unlock(rl); 1666 if (sync) 1667 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1668 return (error); 1669} 1670 1671#ifdef sun 1672int 1673zvol_getefi(void *arg, int flag, uint64_t vs, uint8_t bs) 1674{ 1675 struct uuid uuid = EFI_RESERVED; 1676 efi_gpe_t gpe = { 0 }; 1677 uint32_t crc; 1678 dk_efi_t efi; 1679 int length; 1680 char *ptr; 1681 1682 if (ddi_copyin(arg, &efi, sizeof (dk_efi_t), flag)) 1683 return (SET_ERROR(EFAULT)); 1684 ptr = (char *)(uintptr_t)efi.dki_data_64; 1685 length = efi.dki_length; 1686 /* 1687 * Some clients may attempt to request a PMBR for the 1688 * zvol. Currently this interface will return EINVAL to 1689 * such requests. These requests could be supported by 1690 * adding a check for lba == 0 and consing up an appropriate 1691 * PMBR. 1692 */ 1693 if (efi.dki_lba < 1 || efi.dki_lba > 2 || length <= 0) 1694 return (SET_ERROR(EINVAL)); 1695 1696 gpe.efi_gpe_StartingLBA = LE_64(34ULL); 1697 gpe.efi_gpe_EndingLBA = LE_64((vs >> bs) - 1); 1698 UUID_LE_CONVERT(gpe.efi_gpe_PartitionTypeGUID, uuid); 1699 1700 if (efi.dki_lba == 1) { 1701 efi_gpt_t gpt = { 0 }; 1702 1703 gpt.efi_gpt_Signature = LE_64(EFI_SIGNATURE); 1704 gpt.efi_gpt_Revision = LE_32(EFI_VERSION_CURRENT); 1705 gpt.efi_gpt_HeaderSize = LE_32(sizeof (gpt)); 1706 gpt.efi_gpt_MyLBA = LE_64(1ULL); 1707 gpt.efi_gpt_FirstUsableLBA = LE_64(34ULL); 1708 gpt.efi_gpt_LastUsableLBA = LE_64((vs >> bs) - 1); 1709 gpt.efi_gpt_PartitionEntryLBA = LE_64(2ULL); 1710 gpt.efi_gpt_NumberOfPartitionEntries = LE_32(1); 1711 gpt.efi_gpt_SizeOfPartitionEntry = 1712 LE_32(sizeof (efi_gpe_t)); 1713 CRC32(crc, &gpe, sizeof (gpe), -1U, crc32_table); 1714 gpt.efi_gpt_PartitionEntryArrayCRC32 = LE_32(~crc); 1715 CRC32(crc, &gpt, sizeof (gpt), -1U, crc32_table); 1716 gpt.efi_gpt_HeaderCRC32 = LE_32(~crc); 1717 if (ddi_copyout(&gpt, ptr, MIN(sizeof (gpt), length), 1718 flag)) 1719 return (SET_ERROR(EFAULT)); 1720 ptr += sizeof (gpt); 1721 length -= sizeof (gpt); 1722 } 1723 if (length > 0 && ddi_copyout(&gpe, ptr, MIN(sizeof (gpe), 1724 length), flag)) 1725 return (SET_ERROR(EFAULT)); 1726 return (0); 1727} 1728 1729/* 1730 * BEGIN entry points to allow external callers access to the volume. 1731 */ 1732/* 1733 * Return the volume parameters needed for access from an external caller. 1734 * These values are invariant as long as the volume is held open. 1735 */ 1736int 1737zvol_get_volume_params(minor_t minor, uint64_t *blksize, 1738 uint64_t *max_xfer_len, void **minor_hdl, void **objset_hdl, void **zil_hdl, 1739 void **rl_hdl, void **bonus_hdl) 1740{ 1741 zvol_state_t *zv; 1742 1743 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL); 1744 if (zv == NULL) 1745 return (SET_ERROR(ENXIO)); 1746 if (zv->zv_flags & ZVOL_DUMPIFIED) 1747 return (SET_ERROR(ENXIO)); 1748 1749 ASSERT(blksize && max_xfer_len && minor_hdl && 1750 objset_hdl && zil_hdl && rl_hdl && bonus_hdl); 1751 1752 *blksize = zv->zv_volblocksize; 1753 *max_xfer_len = (uint64_t)zvol_maxphys; 1754 *minor_hdl = zv; 1755 *objset_hdl = zv->zv_objset; 1756 *zil_hdl = zv->zv_zilog; 1757 *rl_hdl = &zv->zv_znode; 1758 *bonus_hdl = zv->zv_dbuf; 1759 return (0); 1760} 1761 1762/* 1763 * Return the current volume size to an external caller. 1764 * The size can change while the volume is open. 1765 */ 1766uint64_t 1767zvol_get_volume_size(void *minor_hdl) 1768{ 1769 zvol_state_t *zv = minor_hdl; 1770 1771 return (zv->zv_volsize); 1772} 1773 1774/* 1775 * Return the current WCE setting to an external caller. 1776 * The WCE setting can change while the volume is open. 1777 */ 1778int 1779zvol_get_volume_wce(void *minor_hdl) 1780{ 1781 zvol_state_t *zv = minor_hdl; 1782 1783 return ((zv->zv_flags & ZVOL_WCE) ? 1 : 0); 1784} 1785 1786/* 1787 * Entry point for external callers to zvol_log_write 1788 */ 1789void 1790zvol_log_write_minor(void *minor_hdl, dmu_tx_t *tx, offset_t off, ssize_t resid, 1791 boolean_t sync) 1792{ 1793 zvol_state_t *zv = minor_hdl; 1794 1795 zvol_log_write(zv, tx, off, resid, sync); 1796} 1797/* 1798 * END entry points to allow external callers access to the volume. 1799 */ 1800#endif /* sun */ 1801 1802/* 1803 * Log a DKIOCFREE/free-long-range to the ZIL with TX_TRUNCATE. 1804 */ 1805static void 1806zvol_log_truncate(zvol_state_t *zv, dmu_tx_t *tx, uint64_t off, uint64_t len, 1807 boolean_t sync) 1808{ 1809 itx_t *itx; 1810 lr_truncate_t *lr; 1811 zilog_t *zilog = zv->zv_zilog; 1812 1813 if (zil_replaying(zilog, tx)) 1814 return; 1815 1816 itx = zil_itx_create(TX_TRUNCATE, sizeof (*lr)); 1817 lr = (lr_truncate_t *)&itx->itx_lr; 1818 lr->lr_foid = ZVOL_OBJ; 1819 lr->lr_offset = off; 1820 lr->lr_length = len; 1821 1822 itx->itx_sync = sync; 1823 zil_itx_assign(zilog, itx, tx); 1824} 1825 1826#ifdef sun 1827/* 1828 * Dirtbag ioctls to support mkfs(1M) for UFS filesystems. See dkio(7I). 1829 * Also a dirtbag dkio ioctl for unmap/free-block functionality. 1830 */ 1831/*ARGSUSED*/ 1832int 1833zvol_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp) 1834{ 1835 zvol_state_t *zv; 1836 struct dk_callback *dkc; 1837 int error = 0; 1838 rl_t *rl; 1839 1840 mutex_enter(&spa_namespace_lock); 1841 1842 zv = zfsdev_get_soft_state(getminor(dev), ZSST_ZVOL); 1843 1844 if (zv == NULL) { 1845 mutex_exit(&spa_namespace_lock); 1846 return (SET_ERROR(ENXIO)); 1847 } 1848 ASSERT(zv->zv_total_opens > 0); 1849 1850 switch (cmd) { 1851 1852 case DKIOCINFO: 1853 { 1854 struct dk_cinfo dki; 1855 1856 bzero(&dki, sizeof (dki)); 1857 (void) strcpy(dki.dki_cname, "zvol"); 1858 (void) strcpy(dki.dki_dname, "zvol"); 1859 dki.dki_ctype = DKC_UNKNOWN; 1860 dki.dki_unit = getminor(dev); 1861 dki.dki_maxtransfer = 1 << (SPA_MAXBLOCKSHIFT - zv->zv_min_bs); 1862 mutex_exit(&spa_namespace_lock); 1863 if (ddi_copyout(&dki, (void *)arg, sizeof (dki), flag)) 1864 error = SET_ERROR(EFAULT); 1865 return (error); 1866 } 1867 1868 case DKIOCGMEDIAINFO: 1869 { 1870 struct dk_minfo dkm; 1871 1872 bzero(&dkm, sizeof (dkm)); 1873 dkm.dki_lbsize = 1U << zv->zv_min_bs; 1874 dkm.dki_capacity = zv->zv_volsize >> zv->zv_min_bs; 1875 dkm.dki_media_type = DK_UNKNOWN; 1876 mutex_exit(&spa_namespace_lock); 1877 if (ddi_copyout(&dkm, (void *)arg, sizeof (dkm), flag)) 1878 error = SET_ERROR(EFAULT); 1879 return (error); 1880 } 1881 1882 case DKIOCGMEDIAINFOEXT: 1883 { 1884 struct dk_minfo_ext dkmext; 1885 1886 bzero(&dkmext, sizeof (dkmext)); 1887 dkmext.dki_lbsize = 1U << zv->zv_min_bs; 1888 dkmext.dki_pbsize = zv->zv_volblocksize; 1889 dkmext.dki_capacity = zv->zv_volsize >> zv->zv_min_bs; 1890 dkmext.dki_media_type = DK_UNKNOWN; 1891 mutex_exit(&spa_namespace_lock); 1892 if (ddi_copyout(&dkmext, (void *)arg, sizeof (dkmext), flag)) 1893 error = SET_ERROR(EFAULT); 1894 return (error); 1895 } 1896 1897 case DKIOCGETEFI: 1898 { 1899 uint64_t vs = zv->zv_volsize; 1900 uint8_t bs = zv->zv_min_bs; 1901 1902 mutex_exit(&spa_namespace_lock); 1903 error = zvol_getefi((void *)arg, flag, vs, bs); 1904 return (error); 1905 } 1906 1907 case DKIOCFLUSHWRITECACHE: 1908 dkc = (struct dk_callback *)arg; 1909 mutex_exit(&spa_namespace_lock); 1910 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1911 if ((flag & FKIOCTL) && dkc != NULL && dkc->dkc_callback) { 1912 (*dkc->dkc_callback)(dkc->dkc_cookie, error); 1913 error = 0; 1914 } 1915 return (error); 1916 1917 case DKIOCGETWCE: 1918 { 1919 int wce = (zv->zv_flags & ZVOL_WCE) ? 1 : 0; 1920 if (ddi_copyout(&wce, (void *)arg, sizeof (int), 1921 flag)) 1922 error = SET_ERROR(EFAULT); 1923 break; 1924 } 1925 case DKIOCSETWCE: 1926 { 1927 int wce; 1928 if (ddi_copyin((void *)arg, &wce, sizeof (int), 1929 flag)) { 1930 error = SET_ERROR(EFAULT); 1931 break; 1932 } 1933 if (wce) { 1934 zv->zv_flags |= ZVOL_WCE; 1935 mutex_exit(&spa_namespace_lock); 1936 } else { 1937 zv->zv_flags &= ~ZVOL_WCE; 1938 mutex_exit(&spa_namespace_lock); 1939 zil_commit(zv->zv_zilog, ZVOL_OBJ); 1940 } 1941 return (0); 1942 } 1943 1944 case DKIOCGGEOM: 1945 case DKIOCGVTOC: 1946 /* 1947 * commands using these (like prtvtoc) expect ENOTSUP 1948 * since we're emulating an EFI label 1949 */ 1950 error = SET_ERROR(ENOTSUP); 1951 break; 1952 1953 case DKIOCDUMPINIT: 1954 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize, 1955 RL_WRITER); 1956 error = zvol_dumpify(zv); 1957 zfs_range_unlock(rl); 1958 break; 1959 1960 case DKIOCDUMPFINI: 1961 if (!(zv->zv_flags & ZVOL_DUMPIFIED)) 1962 break; 1963 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize, 1964 RL_WRITER); 1965 error = zvol_dump_fini(zv); 1966 zfs_range_unlock(rl); 1967 break; 1968 1969 case DKIOCFREE: 1970 { 1971 dkioc_free_t df; 1972 dmu_tx_t *tx; 1973 1974 if (ddi_copyin((void *)arg, &df, sizeof (df), flag)) { 1975 error = SET_ERROR(EFAULT); 1976 break; 1977 } 1978 1979 /* 1980 * Apply Postel's Law to length-checking. If they overshoot, 1981 * just blank out until the end, if there's a need to blank 1982 * out anything. 1983 */ 1984 if (df.df_start >= zv->zv_volsize) 1985 break; /* No need to do anything... */ 1986 if (df.df_start + df.df_length > zv->zv_volsize) 1987 df.df_length = DMU_OBJECT_END; 1988 1989 rl = zfs_range_lock(&zv->zv_znode, df.df_start, df.df_length, 1990 RL_WRITER); 1991 tx = dmu_tx_create(zv->zv_objset); 1992 dmu_tx_mark_netfree(tx); 1993 error = dmu_tx_assign(tx, TXG_WAIT); 1994 if (error != 0) { 1995 dmu_tx_abort(tx); 1996 } else { 1997 zvol_log_truncate(zv, tx, df.df_start, 1998 df.df_length, B_TRUE); 1999 dmu_tx_commit(tx); 2000 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 2001 df.df_start, df.df_length); 2002 } 2003 2004 zfs_range_unlock(rl); 2005 2006 if (error == 0) { 2007 /* 2008 * If the write-cache is disabled or 'sync' property 2009 * is set to 'always' then treat this as a synchronous 2010 * operation (i.e. commit to zil). 2011 */ 2012 if (!(zv->zv_flags & ZVOL_WCE) || 2013 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)) 2014 zil_commit(zv->zv_zilog, ZVOL_OBJ); 2015 2016 /* 2017 * If the caller really wants synchronous writes, and 2018 * can't wait for them, don't return until the write 2019 * is done. 2020 */ 2021 if (df.df_flags & DF_WAIT_SYNC) { 2022 txg_wait_synced( 2023 dmu_objset_pool(zv->zv_objset), 0); 2024 } 2025 } 2026 break; 2027 } 2028 2029 default: 2030 error = SET_ERROR(ENOTTY); 2031 break; 2032 2033 } 2034 mutex_exit(&spa_namespace_lock); 2035 return (error); 2036} 2037#endif /* sun */ 2038 2039int 2040zvol_busy(void) 2041{ 2042 return (zvol_minors != 0); 2043} 2044 2045void 2046zvol_init(void) 2047{ 2048 VERIFY(ddi_soft_state_init(&zfsdev_state, sizeof (zfs_soft_state_t), 2049 1) == 0); 2050 ZFS_LOG(1, "ZVOL Initialized."); 2051} 2052 2053void 2054zvol_fini(void) 2055{ 2056 ddi_soft_state_fini(&zfsdev_state); 2057 ZFS_LOG(1, "ZVOL Deinitialized."); 2058} 2059 2060#ifdef sun 2061/*ARGSUSED*/ 2062static int 2063zfs_mvdev_dump_feature_check(void *arg, dmu_tx_t *tx) 2064{ 2065 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 2066 2067 if (spa_feature_is_active(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP)) 2068 return (1); 2069 return (0); 2070} 2071 2072/*ARGSUSED*/ 2073static void 2074zfs_mvdev_dump_activate_feature_sync(void *arg, dmu_tx_t *tx) 2075{ 2076 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 2077 2078 spa_feature_incr(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP, tx); 2079} 2080 2081static int 2082zvol_dump_init(zvol_state_t *zv, boolean_t resize) 2083{ 2084 dmu_tx_t *tx; 2085 int error; 2086 objset_t *os = zv->zv_objset; 2087 spa_t *spa = dmu_objset_spa(os); 2088 vdev_t *vd = spa->spa_root_vdev; 2089 nvlist_t *nv = NULL; 2090 uint64_t version = spa_version(spa); 2091 enum zio_checksum checksum; 2092 2093 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 2094 ASSERT(vd->vdev_ops == &vdev_root_ops); 2095 2096 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 0, 2097 DMU_OBJECT_END); 2098 /* wait for dmu_free_long_range to actually free the blocks */ 2099 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 2100 2101 /* 2102 * If the pool on which the dump device is being initialized has more 2103 * than one child vdev, check that the MULTI_VDEV_CRASH_DUMP feature is 2104 * enabled. If so, bump that feature's counter to indicate that the 2105 * feature is active. We also check the vdev type to handle the 2106 * following case: 2107 * # zpool create test raidz disk1 disk2 disk3 2108 * Now have spa_root_vdev->vdev_children == 1 (the raidz vdev), 2109 * the raidz vdev itself has 3 children. 2110 */ 2111 if (vd->vdev_children > 1 || vd->vdev_ops == &vdev_raidz_ops) { 2112 if (!spa_feature_is_enabled(spa, 2113 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP)) 2114 return (SET_ERROR(ENOTSUP)); 2115 (void) dsl_sync_task(spa_name(spa), 2116 zfs_mvdev_dump_feature_check, 2117 zfs_mvdev_dump_activate_feature_sync, NULL, 2118 2, ZFS_SPACE_CHECK_RESERVED); 2119 } 2120 2121 tx = dmu_tx_create(os); 2122 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 2123 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 2124 error = dmu_tx_assign(tx, TXG_WAIT); 2125 if (error) { 2126 dmu_tx_abort(tx); 2127 return (error); 2128 } 2129 2130 /* 2131 * If MULTI_VDEV_CRASH_DUMP is active, use the NOPARITY checksum 2132 * function. Otherwise, use the old default -- OFF. 2133 */ 2134 checksum = spa_feature_is_active(spa, 2135 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP) ? ZIO_CHECKSUM_NOPARITY : 2136 ZIO_CHECKSUM_OFF; 2137 2138 /* 2139 * If we are resizing the dump device then we only need to 2140 * update the refreservation to match the newly updated 2141 * zvolsize. Otherwise, we save off the original state of the 2142 * zvol so that we can restore them if the zvol is ever undumpified. 2143 */ 2144 if (resize) { 2145 error = zap_update(os, ZVOL_ZAP_OBJ, 2146 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 2147 &zv->zv_volsize, tx); 2148 } else { 2149 uint64_t checksum, compress, refresrv, vbs, dedup; 2150 2151 error = dsl_prop_get_integer(zv->zv_name, 2152 zfs_prop_to_name(ZFS_PROP_COMPRESSION), &compress, NULL); 2153 error = error ? error : dsl_prop_get_integer(zv->zv_name, 2154 zfs_prop_to_name(ZFS_PROP_CHECKSUM), &checksum, NULL); 2155 error = error ? error : dsl_prop_get_integer(zv->zv_name, 2156 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &refresrv, NULL); 2157 error = error ? error : dsl_prop_get_integer(zv->zv_name, 2158 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &vbs, NULL); 2159 if (version >= SPA_VERSION_DEDUP) { 2160 error = error ? error : 2161 dsl_prop_get_integer(zv->zv_name, 2162 zfs_prop_to_name(ZFS_PROP_DEDUP), &dedup, NULL); 2163 } 2164 2165 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 2166 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, 2167 &compress, tx); 2168 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 2169 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum, tx); 2170 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 2171 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, 2172 &refresrv, tx); 2173 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 2174 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, 2175 &vbs, tx); 2176 error = error ? error : dmu_object_set_blocksize( 2177 os, ZVOL_OBJ, SPA_MAXBLOCKSIZE, 0, tx); 2178 if (version >= SPA_VERSION_DEDUP) { 2179 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ, 2180 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, 2181 &dedup, tx); 2182 } 2183 if (error == 0) 2184 zv->zv_volblocksize = SPA_MAXBLOCKSIZE; 2185 } 2186 dmu_tx_commit(tx); 2187 2188 /* 2189 * We only need update the zvol's property if we are initializing 2190 * the dump area for the first time. 2191 */ 2192 if (!resize) { 2193 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 2194 VERIFY(nvlist_add_uint64(nv, 2195 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 0) == 0); 2196 VERIFY(nvlist_add_uint64(nv, 2197 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 2198 ZIO_COMPRESS_OFF) == 0); 2199 VERIFY(nvlist_add_uint64(nv, 2200 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 2201 checksum) == 0); 2202 if (version >= SPA_VERSION_DEDUP) { 2203 VERIFY(nvlist_add_uint64(nv, 2204 zfs_prop_to_name(ZFS_PROP_DEDUP), 2205 ZIO_CHECKSUM_OFF) == 0); 2206 } 2207 2208 error = zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL, 2209 nv, NULL); 2210 nvlist_free(nv); 2211 2212 if (error) 2213 return (error); 2214 } 2215 2216 /* Allocate the space for the dump */ 2217 error = zvol_prealloc(zv); 2218 return (error); 2219} 2220 2221static int 2222zvol_dumpify(zvol_state_t *zv) 2223{ 2224 int error = 0; 2225 uint64_t dumpsize = 0; 2226 dmu_tx_t *tx; 2227 objset_t *os = zv->zv_objset; 2228 2229 if (zv->zv_flags & ZVOL_RDONLY) 2230 return (SET_ERROR(EROFS)); 2231 2232 if (zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 2233 8, 1, &dumpsize) != 0 || dumpsize != zv->zv_volsize) { 2234 boolean_t resize = (dumpsize > 0); 2235 2236 if ((error = zvol_dump_init(zv, resize)) != 0) { 2237 (void) zvol_dump_fini(zv); 2238 return (error); 2239 } 2240 } 2241 2242 /* 2243 * Build up our lba mapping. 2244 */ 2245 error = zvol_get_lbas(zv); 2246 if (error) { 2247 (void) zvol_dump_fini(zv); 2248 return (error); 2249 } 2250 2251 tx = dmu_tx_create(os); 2252 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 2253 error = dmu_tx_assign(tx, TXG_WAIT); 2254 if (error) { 2255 dmu_tx_abort(tx); 2256 (void) zvol_dump_fini(zv); 2257 return (error); 2258 } 2259 2260 zv->zv_flags |= ZVOL_DUMPIFIED; 2261 error = zap_update(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 8, 1, 2262 &zv->zv_volsize, tx); 2263 dmu_tx_commit(tx); 2264 2265 if (error) { 2266 (void) zvol_dump_fini(zv); 2267 return (error); 2268 } 2269 2270 txg_wait_synced(dmu_objset_pool(os), 0); 2271 return (0); 2272} 2273 2274static int 2275zvol_dump_fini(zvol_state_t *zv) 2276{ 2277 dmu_tx_t *tx; 2278 objset_t *os = zv->zv_objset; 2279 nvlist_t *nv; 2280 int error = 0; 2281 uint64_t checksum, compress, refresrv, vbs, dedup; 2282 uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset)); 2283 2284 /* 2285 * Attempt to restore the zvol back to its pre-dumpified state. 2286 * This is a best-effort attempt as it's possible that not all 2287 * of these properties were initialized during the dumpify process 2288 * (i.e. error during zvol_dump_init). 2289 */ 2290 2291 tx = dmu_tx_create(os); 2292 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); 2293 error = dmu_tx_assign(tx, TXG_WAIT); 2294 if (error) { 2295 dmu_tx_abort(tx); 2296 return (error); 2297 } 2298 (void) zap_remove(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, tx); 2299 dmu_tx_commit(tx); 2300 2301 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2302 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum); 2303 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2304 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, &compress); 2305 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2306 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, &refresrv); 2307 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2308 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, &vbs); 2309 2310 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0); 2311 (void) nvlist_add_uint64(nv, 2312 zfs_prop_to_name(ZFS_PROP_CHECKSUM), checksum); 2313 (void) nvlist_add_uint64(nv, 2314 zfs_prop_to_name(ZFS_PROP_COMPRESSION), compress); 2315 (void) nvlist_add_uint64(nv, 2316 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), refresrv); 2317 if (version >= SPA_VERSION_DEDUP && 2318 zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, 2319 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, &dedup) == 0) { 2320 (void) nvlist_add_uint64(nv, 2321 zfs_prop_to_name(ZFS_PROP_DEDUP), dedup); 2322 } 2323 (void) zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL, 2324 nv, NULL); 2325 nvlist_free(nv); 2326 2327 zvol_free_extents(zv); 2328 zv->zv_flags &= ~ZVOL_DUMPIFIED; 2329 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, DMU_OBJECT_END); 2330 /* wait for dmu_free_long_range to actually free the blocks */ 2331 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); 2332 tx = dmu_tx_create(os); 2333 dmu_tx_hold_bonus(tx, ZVOL_OBJ); 2334 error = dmu_tx_assign(tx, TXG_WAIT); 2335 if (error) { 2336 dmu_tx_abort(tx); 2337 return (error); 2338 } 2339 if (dmu_object_set_blocksize(os, ZVOL_OBJ, vbs, 0, tx) == 0) 2340 zv->zv_volblocksize = vbs; 2341 dmu_tx_commit(tx); 2342 2343 return (0); 2344} 2345#endif /* sun */ 2346 2347static void 2348zvol_geom_run(zvol_state_t *zv) 2349{ 2350 struct g_provider *pp; 2351 2352 pp = zv->zv_provider; 2353 g_error_provider(pp, 0); 2354 2355 kproc_kthread_add(zvol_geom_worker, zv, &zfsproc, NULL, 0, 0, 2356 "zfskern", "zvol %s", pp->name + sizeof(ZVOL_DRIVER)); 2357} 2358 2359static void 2360zvol_geom_destroy(zvol_state_t *zv) 2361{ 2362 struct g_provider *pp; 2363 2364 g_topology_assert(); 2365 2366 mtx_lock(&zv->zv_queue_mtx); 2367 zv->zv_state = 1; 2368 wakeup_one(&zv->zv_queue); 2369 while (zv->zv_state != 2) 2370 msleep(&zv->zv_state, &zv->zv_queue_mtx, 0, "zvol:w", 0); 2371 mtx_destroy(&zv->zv_queue_mtx); 2372 2373 pp = zv->zv_provider; 2374 zv->zv_provider = NULL; 2375 pp->private = NULL; 2376 g_wither_geom(pp->geom, ENXIO); 2377} 2378 2379static int 2380zvol_geom_access(struct g_provider *pp, int acr, int acw, int ace) 2381{ 2382 int count, error, flags; 2383 2384 g_topology_assert(); 2385 2386 /* 2387 * To make it easier we expect either open or close, but not both 2388 * at the same time. 2389 */ 2390 KASSERT((acr >= 0 && acw >= 0 && ace >= 0) || 2391 (acr <= 0 && acw <= 0 && ace <= 0), 2392 ("Unsupported access request to %s (acr=%d, acw=%d, ace=%d).", 2393 pp->name, acr, acw, ace)); 2394 2395 if (pp->private == NULL) { 2396 if (acr <= 0 && acw <= 0 && ace <= 0) 2397 return (0); 2398 return (pp->error); 2399 } 2400 2401 /* 2402 * We don't pass FEXCL flag to zvol_open()/zvol_close() if ace != 0, 2403 * because GEOM already handles that and handles it a bit differently. 2404 * GEOM allows for multiple read/exclusive consumers and ZFS allows 2405 * only one exclusive consumer, no matter if it is reader or writer. 2406 * I like better the way GEOM works so I'll leave it for GEOM to 2407 * decide what to do. 2408 */ 2409 2410 count = acr + acw + ace; 2411 if (count == 0) 2412 return (0); 2413 2414 flags = 0; 2415 if (acr != 0 || ace != 0) 2416 flags |= FREAD; 2417 if (acw != 0) 2418 flags |= FWRITE; 2419 2420 g_topology_unlock(); 2421 if (count > 0) 2422 error = zvol_open(pp, flags, count); 2423 else 2424 error = zvol_close(pp, flags, -count); 2425 g_topology_lock(); 2426 return (error); 2427} 2428 2429static void 2430zvol_geom_start(struct bio *bp) 2431{ 2432 zvol_state_t *zv; 2433 boolean_t first; 2434 2435 zv = bp->bio_to->private; 2436 ASSERT(zv != NULL); 2437 switch (bp->bio_cmd) { 2438 case BIO_FLUSH: 2439 if (!THREAD_CAN_SLEEP()) 2440 goto enqueue; 2441 zil_commit(zv->zv_zilog, ZVOL_OBJ); 2442 g_io_deliver(bp, 0); 2443 break; 2444 case BIO_READ: 2445 case BIO_WRITE: 2446 case BIO_DELETE: 2447 if (!THREAD_CAN_SLEEP()) 2448 goto enqueue; 2449 zvol_strategy(bp); 2450 break; 2451 case BIO_GETATTR: 2452 if (g_handleattr_int(bp, "GEOM::candelete", 1)) 2453 return; 2454 /* FALLTHROUGH */ 2455 default: 2456 g_io_deliver(bp, EOPNOTSUPP); 2457 break; 2458 } 2459 return; 2460 2461enqueue: 2462 mtx_lock(&zv->zv_queue_mtx); 2463 first = (bioq_first(&zv->zv_queue) == NULL); 2464 bioq_insert_tail(&zv->zv_queue, bp); 2465 mtx_unlock(&zv->zv_queue_mtx); 2466 if (first) 2467 wakeup_one(&zv->zv_queue); 2468} 2469 2470static void 2471zvol_geom_worker(void *arg) 2472{ 2473 zvol_state_t *zv; 2474 struct bio *bp; 2475 2476 thread_lock(curthread); 2477 sched_prio(curthread, PRIBIO); 2478 thread_unlock(curthread); 2479 2480 zv = arg; 2481 for (;;) { 2482 mtx_lock(&zv->zv_queue_mtx); 2483 bp = bioq_takefirst(&zv->zv_queue); 2484 if (bp == NULL) { 2485 if (zv->zv_state == 1) { 2486 zv->zv_state = 2; 2487 wakeup(&zv->zv_state); 2488 mtx_unlock(&zv->zv_queue_mtx); 2489 kthread_exit(); 2490 } 2491 msleep(&zv->zv_queue, &zv->zv_queue_mtx, PRIBIO | PDROP, 2492 "zvol:io", 0); 2493 continue; 2494 } 2495 mtx_unlock(&zv->zv_queue_mtx); 2496 switch (bp->bio_cmd) { 2497 case BIO_FLUSH: 2498 zil_commit(zv->zv_zilog, ZVOL_OBJ); 2499 g_io_deliver(bp, 0); 2500 break; 2501 case BIO_READ: 2502 case BIO_WRITE: 2503 zvol_strategy(bp); 2504 break; 2505 } 2506 } 2507} 2508 2509extern boolean_t dataset_name_hidden(const char *name); 2510 2511static int 2512zvol_create_snapshots(objset_t *os, const char *name) 2513{ 2514 uint64_t cookie, obj; 2515 char *sname; 2516 int error, len; 2517 2518 cookie = obj = 0; 2519 sname = kmem_alloc(MAXPATHLEN, KM_SLEEP); 2520 2521#if 0 2522 (void) dmu_objset_find(name, dmu_objset_prefetch, NULL, 2523 DS_FIND_SNAPSHOTS); 2524#endif 2525 2526 for (;;) { 2527 len = snprintf(sname, MAXPATHLEN, "%s@", name); 2528 if (len >= MAXPATHLEN) { 2529 dmu_objset_rele(os, FTAG); 2530 error = ENAMETOOLONG; 2531 break; 2532 } 2533 2534 dsl_pool_config_enter(dmu_objset_pool(os), FTAG); 2535 error = dmu_snapshot_list_next(os, MAXPATHLEN - len, 2536 sname + len, &obj, &cookie, NULL); 2537 dsl_pool_config_exit(dmu_objset_pool(os), FTAG); 2538 if (error != 0) { 2539 if (error == ENOENT) 2540 error = 0; 2541 break; 2542 } 2543 2544 if ((error = zvol_create_minor(sname)) != 0) { 2545 printf("ZFS WARNING: Unable to create ZVOL %s (error=%d).\n", 2546 sname, error); 2547 break; 2548 } 2549 } 2550 2551 kmem_free(sname, MAXPATHLEN); 2552 return (error); 2553} 2554 2555int 2556zvol_create_minors(const char *name) 2557{ 2558 uint64_t cookie; 2559 objset_t *os; 2560 char *osname, *p; 2561 int error, len; 2562 2563 if (dataset_name_hidden(name)) 2564 return (0); 2565 2566 if ((error = dmu_objset_hold(name, FTAG, &os)) != 0) { 2567 printf("ZFS WARNING: Unable to put hold on %s (error=%d).\n", 2568 name, error); 2569 return (error); 2570 } 2571 if (dmu_objset_type(os) == DMU_OST_ZVOL) { 2572 dsl_dataset_long_hold(os->os_dsl_dataset, FTAG); 2573 dsl_pool_rele(dmu_objset_pool(os), FTAG); 2574 if ((error = zvol_create_minor(name)) == 0) 2575 error = zvol_create_snapshots(os, name); 2576 else { 2577 printf("ZFS WARNING: Unable to create ZVOL %s (error=%d).\n", 2578 name, error); 2579 } 2580 dsl_dataset_long_rele(os->os_dsl_dataset, FTAG); 2581 dsl_dataset_rele(os->os_dsl_dataset, FTAG); 2582 return (error); 2583 } 2584 if (dmu_objset_type(os) != DMU_OST_ZFS) { 2585 dmu_objset_rele(os, FTAG); 2586 return (0); 2587 } 2588 2589 osname = kmem_alloc(MAXPATHLEN, KM_SLEEP); 2590 if (snprintf(osname, MAXPATHLEN, "%s/", name) >= MAXPATHLEN) { 2591 dmu_objset_rele(os, FTAG); 2592 kmem_free(osname, MAXPATHLEN); 2593 return (ENOENT); 2594 } 2595 p = osname + strlen(osname); 2596 len = MAXPATHLEN - (p - osname); 2597 2598#if 0 2599 /* Prefetch the datasets. */ 2600 cookie = 0; 2601 while (dmu_dir_list_next(os, len, p, NULL, &cookie) == 0) { 2602 if (!dataset_name_hidden(osname)) 2603 (void) dmu_objset_prefetch(osname, NULL); 2604 } 2605#endif 2606 2607 cookie = 0; 2608 while (dmu_dir_list_next(os, MAXPATHLEN - (p - osname), p, NULL, 2609 &cookie) == 0) { 2610 dmu_objset_rele(os, FTAG); 2611 (void)zvol_create_minors(osname); 2612 if ((error = dmu_objset_hold(name, FTAG, &os)) != 0) { 2613 printf("ZFS WARNING: Unable to put hold on %s (error=%d).\n", 2614 name, error); 2615 return (error); 2616 } 2617 } 2618 2619 dmu_objset_rele(os, FTAG); 2620 kmem_free(osname, MAXPATHLEN); 2621 return (0); 2622} 2623 2624static void 2625zvol_rename_minor(zvol_state_t *zv, const char *newname) 2626{ 2627 struct g_geom *gp; 2628 struct g_provider *pp; 2629 struct cdev *dev; 2630 2631 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 2632 2633 if (zv->zv_volmode == ZFS_VOLMODE_GEOM) { 2634 g_topology_lock(); 2635 pp = zv->zv_provider; 2636 ASSERT(pp != NULL); 2637 gp = pp->geom; 2638 ASSERT(gp != NULL); 2639 2640 zv->zv_provider = NULL; 2641 g_wither_provider(pp, ENXIO); 2642 2643 pp = g_new_providerf(gp, "%s/%s", ZVOL_DRIVER, newname); 2644 pp->flags |= G_PF_DIRECT_RECEIVE | G_PF_DIRECT_SEND; 2645 pp->sectorsize = DEV_BSIZE; 2646 pp->mediasize = zv->zv_volsize; 2647 pp->private = zv; 2648 zv->zv_provider = pp; 2649 g_error_provider(pp, 0); 2650 g_topology_unlock(); 2651 } else if (zv->zv_volmode == ZFS_VOLMODE_DEV) { 2652 dev = zv->zv_dev; 2653 ASSERT(dev != NULL); 2654 zv->zv_dev = NULL; 2655 destroy_dev(dev); 2656 2657 if (make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK, 2658 &dev, &zvol_cdevsw, NULL, UID_ROOT, GID_OPERATOR, 2659 0640, "%s/%s", ZVOL_DRIVER, newname) == 0) { 2660 zv->zv_dev = dev; 2661 dev->si_iosize_max = MAXPHYS; 2662 dev->si_drv2 = zv; 2663 } 2664 } 2665 strlcpy(zv->zv_name, newname, sizeof(zv->zv_name)); 2666} 2667 2668void 2669zvol_rename_minors(const char *oldname, const char *newname) 2670{ 2671 char name[MAXPATHLEN]; 2672 struct g_provider *pp; 2673 struct g_geom *gp; 2674 size_t oldnamelen, newnamelen; 2675 zvol_state_t *zv; 2676 char *namebuf; 2677 2678 oldnamelen = strlen(oldname); 2679 newnamelen = strlen(newname); 2680 2681 DROP_GIANT(); 2682 mutex_enter(&spa_namespace_lock); 2683 2684 LIST_FOREACH(zv, &all_zvols, zv_links) { 2685 if (strcmp(zv->zv_name, oldname) == 0) { 2686 zvol_rename_minor(zv, newname); 2687 } else if (strncmp(zv->zv_name, oldname, oldnamelen) == 0 && 2688 (zv->zv_name[oldnamelen] == '/' || 2689 zv->zv_name[oldnamelen] == '@')) { 2690 snprintf(name, sizeof(name), "%s%c%s", newname, 2691 zv->zv_name[oldnamelen], 2692 zv->zv_name + oldnamelen + 1); 2693 zvol_rename_minor(zv, name); 2694 } 2695 } 2696 2697 mutex_exit(&spa_namespace_lock); 2698 PICKUP_GIANT(); 2699} 2700 2701static int 2702zvol_d_open(struct cdev *dev, int flags, int fmt, struct thread *td) 2703{ 2704 zvol_state_t *zv; 2705 int err = 0; 2706 2707 mutex_enter(&spa_namespace_lock); 2708 zv = dev->si_drv2; 2709 if (zv == NULL) { 2710 mutex_exit(&spa_namespace_lock); 2711 return(ENXIO); /* zvol_create_minor() not done yet */ 2712 } 2713 2714 if (zv->zv_total_opens == 0) 2715 err = zvol_first_open(zv); 2716 if (err) { 2717 mutex_exit(&spa_namespace_lock); 2718 return (err); 2719 } 2720 if ((flags & FWRITE) && (zv->zv_flags & ZVOL_RDONLY)) { 2721 err = SET_ERROR(EROFS); 2722 goto out; 2723 } 2724 if (zv->zv_flags & ZVOL_EXCL) { 2725 err = SET_ERROR(EBUSY); 2726 goto out; 2727 } 2728#ifdef FEXCL 2729 if (flags & FEXCL) { 2730 if (zv->zv_total_opens != 0) { 2731 err = SET_ERROR(EBUSY); 2732 goto out; 2733 } 2734 zv->zv_flags |= ZVOL_EXCL; 2735 } 2736#endif 2737 2738 zv->zv_total_opens++; 2739 mutex_exit(&spa_namespace_lock); 2740 return (err); 2741out: 2742 if (zv->zv_total_opens == 0) 2743 zvol_last_close(zv); 2744 mutex_exit(&spa_namespace_lock); 2745 return (err); 2746} 2747 2748static int 2749zvol_d_close(struct cdev *dev, int flags, int fmt, struct thread *td) 2750{ 2751 zvol_state_t *zv; 2752 int err = 0; 2753 2754 mutex_enter(&spa_namespace_lock); 2755 zv = dev->si_drv2; 2756 if (zv == NULL) { 2757 mutex_exit(&spa_namespace_lock); 2758 return(ENXIO); 2759 } 2760 2761 if (zv->zv_flags & ZVOL_EXCL) { 2762 ASSERT(zv->zv_total_opens == 1); 2763 zv->zv_flags &= ~ZVOL_EXCL; 2764 } 2765 2766 /* 2767 * If the open count is zero, this is a spurious close. 2768 * That indicates a bug in the kernel / DDI framework. 2769 */ 2770 ASSERT(zv->zv_total_opens != 0); 2771 2772 /* 2773 * You may get multiple opens, but only one close. 2774 */ 2775 zv->zv_total_opens--; 2776 2777 if (zv->zv_total_opens == 0) 2778 zvol_last_close(zv); 2779 2780 mutex_exit(&spa_namespace_lock); 2781 return (0); 2782} 2783 2784static int 2785zvol_d_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td) 2786{ 2787 zvol_state_t *zv; 2788 rl_t *rl; 2789 off_t offset, length, chunk; 2790 int i, error; 2791 u_int u; 2792 2793 zv = dev->si_drv2; 2794 2795 error = 0; 2796 KASSERT(zv->zv_total_opens > 0, 2797 ("Device with zero access count in zvol_d_ioctl")); 2798 2799 i = IOCPARM_LEN(cmd); 2800 switch (cmd) { 2801 case DIOCGSECTORSIZE: 2802 *(u_int *)data = DEV_BSIZE; 2803 break; 2804 case DIOCGMEDIASIZE: 2805 *(off_t *)data = zv->zv_volsize; 2806 break; 2807 case DIOCGFLUSH: 2808 zil_commit(zv->zv_zilog, ZVOL_OBJ); 2809 break; 2810 case DIOCGDELETE: 2811 offset = ((off_t *)data)[0]; 2812 length = ((off_t *)data)[1]; 2813 if ((offset % DEV_BSIZE) != 0 || (length % DEV_BSIZE) != 0 || 2814 offset < 0 || offset >= zv->zv_volsize || 2815 length <= 0) { 2816 printf("%s: offset=%jd length=%jd\n", __func__, offset, 2817 length); 2818 error = EINVAL; 2819 break; 2820 } 2821 2822 rl = zfs_range_lock(&zv->zv_znode, offset, length, RL_WRITER); 2823 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset); 2824 error = dmu_tx_assign(tx, TXG_WAIT); 2825 if (error != 0) { 2826 dmu_tx_abort(tx); 2827 } else { 2828 zvol_log_truncate(zv, tx, offset, length, B_TRUE); 2829 dmu_tx_commit(tx); 2830 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 2831 offset, length); 2832 } 2833 zfs_range_unlock(rl); 2834 if (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS) 2835 zil_commit(zv->zv_zilog, ZVOL_OBJ); 2836 break; 2837 case DIOCGSTRIPESIZE: 2838 *(off_t *)data = zv->zv_volblocksize; 2839 break; 2840 case DIOCGSTRIPEOFFSET: 2841 *(off_t *)data = 0; 2842 break; 2843 default: 2844 error = ENOIOCTL; 2845 } 2846 2847 return (error); 2848} 2849