1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 *
24 * Portions Copyright 2010 Robert Milkowski
25 *
26 * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
27 * Copyright (c) 2012 by Delphix. All rights reserved.
28 */
29
30 /*
31 * ZFS volume emulation driver.
32 *
33 * Makes a DMU object look like a volume of arbitrary size, up to 2^64 bytes.
34 * Volumes are accessed through the symbolic links named:
35 *
36 * /dev/zvol/dsk/<pool_name>/<dataset_name>
37 * /dev/zvol/rdsk/<pool_name>/<dataset_name>
38 *
39 * These links are created by the /dev filesystem (sdev_zvolops.c).
40 * Volumes are persistent through reboot. No user command needs to be
41 * run before opening and using a device.
42 */
43
44 #include <sys/types.h>
45 #include <sys/param.h>
46 #include <sys/errno.h>
47 #include <sys/uio.h>
48 #include <sys/buf.h>
49 #include <sys/modctl.h>
50 #include <sys/open.h>
51 #include <sys/kmem.h>
52 #include <sys/conf.h>
53 #include <sys/cmn_err.h>
54 #include <sys/stat.h>
55 #include <sys/zap.h>
56 #include <sys/spa.h>
57 #include <sys/zio.h>
58 #include <sys/dmu_traverse.h>
59 #include <sys/dnode.h>
60 #include <sys/dsl_dataset.h>
61 #include <sys/dsl_prop.h>
62 #include <sys/dkio.h>
63 #include <sys/efi_partition.h>
64 #include <sys/byteorder.h>
65 #include <sys/pathname.h>
66 #include <sys/ddi.h>
67 #include <sys/sunddi.h>
68 #include <sys/crc32.h>
69 #include <sys/dirent.h>
70 #include <sys/policy.h>
71 #include <sys/fs/zfs.h>
72 #include <sys/zfs_ioctl.h>
73 #include <sys/mkdev.h>
74 #include <sys/zil.h>
75 #include <sys/refcount.h>
76 #include <sys/zfs_znode.h>
77 #include <sys/zfs_rlock.h>
78 #include <sys/vdev_disk.h>
79 #include <sys/vdev_impl.h>
80 #include <sys/zvol.h>
81 #include <sys/dumphdr.h>
82 #include <sys/zil_impl.h>
83
84 #include "zfs_namecheck.h"
85
86 void *zfsdev_state;
87 static char *zvol_tag = "zvol_tag";
88
89 #define ZVOL_DUMPSIZE "dumpsize"
90
91 /*
92 * This lock protects the zfsdev_state structure from being modified
93 * while it's being used, e.g. an open that comes in before a create
94 * finishes. It also protects temporary opens of the dataset so that,
95 * e.g., an open doesn't get a spurious EBUSY.
96 */
97 kmutex_t zfsdev_state_lock;
98 static uint32_t zvol_minors;
99
100 typedef struct zvol_extent {
101 list_node_t ze_node;
102 dva_t ze_dva; /* dva associated with this extent */
103 uint64_t ze_nblks; /* number of blocks in extent */
104 } zvol_extent_t;
105
106 /*
107 * The in-core state of each volume.
108 */
109 typedef struct zvol_state {
110 char zv_name[MAXPATHLEN]; /* pool/dd name */
111 uint64_t zv_volsize; /* amount of space we advertise */
112 uint64_t zv_volblocksize; /* volume block size */
113 minor_t zv_minor; /* minor number */
114 uint8_t zv_min_bs; /* minimum addressable block shift */
115 uint8_t zv_flags; /* readonly, dumpified, etc. */
116 objset_t *zv_objset; /* objset handle */
117 uint32_t zv_open_count[OTYPCNT]; /* open counts */
118 uint32_t zv_total_opens; /* total open count */
119 zilog_t *zv_zilog; /* ZIL handle */
120 list_t zv_extents; /* List of extents for dump */
121 znode_t zv_znode; /* for range locking */
122 dmu_buf_t *zv_dbuf; /* bonus handle */
123 } zvol_state_t;
124
125 /*
126 * zvol specific flags
127 */
128 #define ZVOL_RDONLY 0x1
129 #define ZVOL_DUMPIFIED 0x2
130 #define ZVOL_EXCL 0x4
131 #define ZVOL_WCE 0x8
132
133 /*
134 * zvol maximum transfer in one DMU tx.
135 */
136 int zvol_maxphys = DMU_MAX_ACCESS/2;
137
138 extern int zfs_set_prop_nvlist(const char *, zprop_source_t,
139 nvlist_t *, nvlist_t *);
140 static int zvol_remove_zv(zvol_state_t *);
141 static int zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio);
142 static int zvol_dumpify(zvol_state_t *zv);
143 static int zvol_dump_fini(zvol_state_t *zv);
144 static int zvol_dump_init(zvol_state_t *zv, boolean_t resize);
145
146 static void
147 zvol_size_changed(uint64_t volsize, major_t maj, minor_t min)
148 {
149 dev_t dev = makedevice(maj, min);
150
151 VERIFY(ddi_prop_update_int64(dev, zfs_dip,
152 "Size", volsize) == DDI_SUCCESS);
153 VERIFY(ddi_prop_update_int64(dev, zfs_dip,
154 "Nblocks", lbtodb(volsize)) == DDI_SUCCESS);
155
156 /* Notify specfs to invalidate the cached size */
157 spec_size_invalidate(dev, VBLK);
158 spec_size_invalidate(dev, VCHR);
159 }
160
161 int
162 zvol_check_volsize(uint64_t volsize, uint64_t blocksize)
163 {
164 if (volsize == 0)
165 return (EINVAL);
166
167 if (volsize % blocksize != 0)
168 return (EINVAL);
169
170 #ifdef _ILP32
171 if (volsize - 1 > SPEC_MAXOFFSET_T)
172 return (EOVERFLOW);
173 #endif
174 return (0);
175 }
176
177 int
178 zvol_check_volblocksize(uint64_t volblocksize)
179 {
180 if (volblocksize < SPA_MINBLOCKSIZE ||
181 volblocksize > SPA_MAXBLOCKSIZE ||
182 !ISP2(volblocksize))
183 return (EDOM);
184
185 return (0);
186 }
187
188 int
189 zvol_get_stats(objset_t *os, nvlist_t *nv)
190 {
191 int error;
192 dmu_object_info_t doi;
193 uint64_t val;
194
195 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val);
196 if (error)
197 return (error);
198
199 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val);
200
201 error = dmu_object_info(os, ZVOL_OBJ, &doi);
202
203 if (error == 0) {
204 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE,
205 doi.doi_data_block_size);
206 }
207
208 return (error);
209 }
210
211 static zvol_state_t *
212 zvol_minor_lookup(const char *name)
213 {
214 minor_t minor;
215 zvol_state_t *zv;
216
217 ASSERT(MUTEX_HELD(&zfsdev_state_lock));
218
219 for (minor = 1; minor <= ZFSDEV_MAX_MINOR; minor++) {
220 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
221 if (zv == NULL)
222 continue;
223 if (strcmp(zv->zv_name, name) == 0)
224 return (zv);
225 }
226
227 return (NULL);
228 }
229
230 /* extent mapping arg */
231 struct maparg {
232 zvol_state_t *ma_zv;
233 uint64_t ma_blks;
234 };
235
236 /*ARGSUSED*/
237 static int
238 zvol_map_block(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, arc_buf_t *pbuf,
239 const zbookmark_t *zb, const dnode_phys_t *dnp, void *arg)
240 {
241 struct maparg *ma = arg;
242 zvol_extent_t *ze;
243 int bs = ma->ma_zv->zv_volblocksize;
244
245 if (bp == NULL || zb->zb_object != ZVOL_OBJ || zb->zb_level != 0)
246 return (0);
247
248 VERIFY3U(ma->ma_blks, ==, zb->zb_blkid);
249 ma->ma_blks++;
250
251 /* Abort immediately if we have encountered gang blocks */
252 if (BP_IS_GANG(bp))
253 return (EFRAGS);
254
255 /*
256 * See if the block is at the end of the previous extent.
257 */
258 ze = list_tail(&ma->ma_zv->zv_extents);
259 if (ze &&
260 DVA_GET_VDEV(BP_IDENTITY(bp)) == DVA_GET_VDEV(&ze->ze_dva) &&
261 DVA_GET_OFFSET(BP_IDENTITY(bp)) ==
262 DVA_GET_OFFSET(&ze->ze_dva) + ze->ze_nblks * bs) {
263 ze->ze_nblks++;
264 return (0);
265 }
266
267 dprintf_bp(bp, "%s", "next blkptr:");
268
269 /* start a new extent */
270 ze = kmem_zalloc(sizeof (zvol_extent_t), KM_SLEEP);
271 ze->ze_dva = bp->blk_dva[0]; /* structure assignment */
272 ze->ze_nblks = 1;
273 list_insert_tail(&ma->ma_zv->zv_extents, ze);
274 return (0);
275 }
276
277 static void
278 zvol_free_extents(zvol_state_t *zv)
279 {
280 zvol_extent_t *ze;
281
282 while (ze = list_head(&zv->zv_extents)) {
283 list_remove(&zv->zv_extents, ze);
284 kmem_free(ze, sizeof (zvol_extent_t));
285 }
286 }
287
288 static int
289 zvol_get_lbas(zvol_state_t *zv)
290 {
291 objset_t *os = zv->zv_objset;
292 struct maparg ma;
293 int err;
294
295 ma.ma_zv = zv;
296 ma.ma_blks = 0;
297 zvol_free_extents(zv);
298
299 /* commit any in-flight changes before traversing the dataset */
300 txg_wait_synced(dmu_objset_pool(os), 0);
301 err = traverse_dataset(dmu_objset_ds(os), 0,
302 TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA, zvol_map_block, &ma);
303 if (err || ma.ma_blks != (zv->zv_volsize / zv->zv_volblocksize)) {
304 zvol_free_extents(zv);
305 return (err ? err : EIO);
306 }
307
308 return (0);
309 }
310
311 /* ARGSUSED */
312 void
313 zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx)
314 {
315 zfs_creat_t *zct = arg;
316 nvlist_t *nvprops = zct->zct_props;
317 int error;
318 uint64_t volblocksize, volsize;
319
320 VERIFY(nvlist_lookup_uint64(nvprops,
321 zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0);
322 if (nvlist_lookup_uint64(nvprops,
323 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0)
324 volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE);
325
326 /*
327 * These properties must be removed from the list so the generic
328 * property setting step won't apply to them.
329 */
330 VERIFY(nvlist_remove_all(nvprops,
331 zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0);
332 (void) nvlist_remove_all(nvprops,
333 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE));
334
335 error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize,
336 DMU_OT_NONE, 0, tx);
337 ASSERT(error == 0);
338
339 error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP,
340 DMU_OT_NONE, 0, tx);
341 ASSERT(error == 0);
342
343 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx);
344 ASSERT(error == 0);
345 }
346
347 /*
348 * Replay a TX_TRUNCATE ZIL transaction if asked. TX_TRUNCATE is how we
349 * implement DKIOCFREE/free-long-range.
350 */
351 static int
352 zvol_replay_truncate(zvol_state_t *zv, lr_truncate_t *lr, boolean_t byteswap)
353 {
354 uint64_t offset, length;
355
356 if (byteswap)
357 byteswap_uint64_array(lr, sizeof (*lr));
358
359 offset = lr->lr_offset;
360 length = lr->lr_length;
361
362 return (dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, offset, length));
363 }
364
365 /*
366 * Replay a TX_WRITE ZIL transaction that didn't get committed
367 * after a system failure
368 */
369 static int
370 zvol_replay_write(zvol_state_t *zv, lr_write_t *lr, boolean_t byteswap)
371 {
372 objset_t *os = zv->zv_objset;
373 char *data = (char *)(lr + 1); /* data follows lr_write_t */
374 uint64_t offset, length;
375 dmu_tx_t *tx;
376 int error;
377
378 if (byteswap)
379 byteswap_uint64_array(lr, sizeof (*lr));
380
381 offset = lr->lr_offset;
382 length = lr->lr_length;
383
384 /* If it's a dmu_sync() block, write the whole block */
385 if (lr->lr_common.lrc_reclen == sizeof (lr_write_t)) {
386 uint64_t blocksize = BP_GET_LSIZE(&lr->lr_blkptr);
387 if (length < blocksize) {
388 offset -= offset % blocksize;
389 length = blocksize;
390 }
391 }
392
393 tx = dmu_tx_create(os);
394 dmu_tx_hold_write(tx, ZVOL_OBJ, offset, length);
395 error = dmu_tx_assign(tx, TXG_WAIT);
396 if (error) {
397 dmu_tx_abort(tx);
398 } else {
399 dmu_write(os, ZVOL_OBJ, offset, length, data, tx);
400 dmu_tx_commit(tx);
401 }
402
403 return (error);
404 }
405
406 /* ARGSUSED */
407 static int
408 zvol_replay_err(zvol_state_t *zv, lr_t *lr, boolean_t byteswap)
409 {
410 return (ENOTSUP);
411 }
412
413 /*
414 * Callback vectors for replaying records.
415 * Only TX_WRITE and TX_TRUNCATE are needed for zvol.
416 */
417 zil_replay_func_t *zvol_replay_vector[TX_MAX_TYPE] = {
418 zvol_replay_err, /* 0 no such transaction type */
419 zvol_replay_err, /* TX_CREATE */
420 zvol_replay_err, /* TX_MKDIR */
421 zvol_replay_err, /* TX_MKXATTR */
422 zvol_replay_err, /* TX_SYMLINK */
423 zvol_replay_err, /* TX_REMOVE */
424 zvol_replay_err, /* TX_RMDIR */
425 zvol_replay_err, /* TX_LINK */
426 zvol_replay_err, /* TX_RENAME */
427 zvol_replay_write, /* TX_WRITE */
428 zvol_replay_truncate, /* TX_TRUNCATE */
429 zvol_replay_err, /* TX_SETATTR */
430 zvol_replay_err, /* TX_ACL */
431 zvol_replay_err, /* TX_CREATE_ACL */
432 zvol_replay_err, /* TX_CREATE_ATTR */
433 zvol_replay_err, /* TX_CREATE_ACL_ATTR */
434 zvol_replay_err, /* TX_MKDIR_ACL */
435 zvol_replay_err, /* TX_MKDIR_ATTR */
436 zvol_replay_err, /* TX_MKDIR_ACL_ATTR */
437 zvol_replay_err, /* TX_WRITE2 */
438 };
439
440 int
441 zvol_name2minor(const char *name, minor_t *minor)
442 {
443 zvol_state_t *zv;
444
445 mutex_enter(&zfsdev_state_lock);
446 zv = zvol_minor_lookup(name);
447 if (minor && zv)
448 *minor = zv->zv_minor;
449 mutex_exit(&zfsdev_state_lock);
450 return (zv ? 0 : -1);
451 }
452
453 /*
454 * Create a minor node (plus a whole lot more) for the specified volume.
455 */
456 int
457 zvol_create_minor(const char *name)
458 {
459 zfs_soft_state_t *zs;
460 zvol_state_t *zv;
461 objset_t *os;
462 dmu_object_info_t doi;
463 minor_t minor = 0;
464 char chrbuf[30], blkbuf[30];
465 int error;
466
467 mutex_enter(&zfsdev_state_lock);
468
469 if (zvol_minor_lookup(name) != NULL) {
470 mutex_exit(&zfsdev_state_lock);
471 return (EEXIST);
472 }
473
474 /* lie and say we're read-only */
475 error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, FTAG, &os);
476
477 if (error) {
478 mutex_exit(&zfsdev_state_lock);
479 return (error);
480 }
481
482 if ((minor = zfsdev_minor_alloc()) == 0) {
483 dmu_objset_disown(os, FTAG);
484 mutex_exit(&zfsdev_state_lock);
485 return (ENXIO);
486 }
487
488 if (ddi_soft_state_zalloc(zfsdev_state, minor) != DDI_SUCCESS) {
489 dmu_objset_disown(os, FTAG);
490 mutex_exit(&zfsdev_state_lock);
491 return (EAGAIN);
492 }
493 (void) ddi_prop_update_string(minor, zfs_dip, ZVOL_PROP_NAME,
494 (char *)name);
495
496 (void) snprintf(chrbuf, sizeof (chrbuf), "%u,raw", minor);
497
498 if (ddi_create_minor_node(zfs_dip, chrbuf, S_IFCHR,
499 minor, DDI_PSEUDO, 0) == DDI_FAILURE) {
500 ddi_soft_state_free(zfsdev_state, minor);
501 dmu_objset_disown(os, FTAG);
502 mutex_exit(&zfsdev_state_lock);
503 return (EAGAIN);
504 }
505
506 (void) snprintf(blkbuf, sizeof (blkbuf), "%u", minor);
507
508 if (ddi_create_minor_node(zfs_dip, blkbuf, S_IFBLK,
509 minor, DDI_PSEUDO, 0) == DDI_FAILURE) {
510 ddi_remove_minor_node(zfs_dip, chrbuf);
511 ddi_soft_state_free(zfsdev_state, minor);
512 dmu_objset_disown(os, FTAG);
513 mutex_exit(&zfsdev_state_lock);
514 return (EAGAIN);
515 }
516
517 zs = ddi_get_soft_state(zfsdev_state, minor);
518 zs->zss_type = ZSST_ZVOL;
519 zv = zs->zss_data = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP);
520 (void) strlcpy(zv->zv_name, name, MAXPATHLEN);
521 zv->zv_min_bs = DEV_BSHIFT;
522 zv->zv_minor = minor;
523 zv->zv_objset = os;
524 if (dmu_objset_is_snapshot(os) || !spa_writeable(dmu_objset_spa(os)))
525 zv->zv_flags |= ZVOL_RDONLY;
526 mutex_init(&zv->zv_znode.z_range_lock, NULL, MUTEX_DEFAULT, NULL);
527 avl_create(&zv->zv_znode.z_range_avl, zfs_range_compare,
528 sizeof (rl_t), offsetof(rl_t, r_node));
529 list_create(&zv->zv_extents, sizeof (zvol_extent_t),
530 offsetof(zvol_extent_t, ze_node));
531 /* get and cache the blocksize */
532 error = dmu_object_info(os, ZVOL_OBJ, &doi);
533 ASSERT(error == 0);
534 zv->zv_volblocksize = doi.doi_data_block_size;
535
536 if (spa_writeable(dmu_objset_spa(os))) {
537 if (zil_replay_disable)
538 zil_destroy(dmu_objset_zil(os), B_FALSE);
539 else
540 zil_replay(os, zv, zvol_replay_vector);
541 }
542 dmu_objset_disown(os, FTAG);
543 zv->zv_objset = NULL;
544
545 zvol_minors++;
546
547 mutex_exit(&zfsdev_state_lock);
548
549 return (0);
550 }
551
552 /*
553 * Remove minor node for the specified volume.
554 */
555 static int
556 zvol_remove_zv(zvol_state_t *zv)
557 {
558 char nmbuf[20];
559 minor_t minor = zv->zv_minor;
560
561 ASSERT(MUTEX_HELD(&zfsdev_state_lock));
562 if (zv->zv_total_opens != 0)
563 return (EBUSY);
564
565 (void) snprintf(nmbuf, sizeof (nmbuf), "%u,raw", minor);
566 ddi_remove_minor_node(zfs_dip, nmbuf);
567
568 (void) snprintf(nmbuf, sizeof (nmbuf), "%u", minor);
569 ddi_remove_minor_node(zfs_dip, nmbuf);
570
571 avl_destroy(&zv->zv_znode.z_range_avl);
572 mutex_destroy(&zv->zv_znode.z_range_lock);
573
574 kmem_free(zv, sizeof (zvol_state_t));
575
576 ddi_soft_state_free(zfsdev_state, minor);
577
578 zvol_minors--;
579 return (0);
580 }
581
582 int
583 zvol_remove_minor(const char *name)
584 {
585 zvol_state_t *zv;
586 int rc;
587
588 mutex_enter(&zfsdev_state_lock);
589 if ((zv = zvol_minor_lookup(name)) == NULL) {
590 mutex_exit(&zfsdev_state_lock);
591 return (ENXIO);
592 }
593 rc = zvol_remove_zv(zv);
594 mutex_exit(&zfsdev_state_lock);
595 return (rc);
596 }
597
598 int
599 zvol_first_open(zvol_state_t *zv)
600 {
601 objset_t *os;
602 uint64_t volsize;
603 int error;
604 uint64_t readonly;
605
606 /* lie and say we're read-only */
607 error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, B_TRUE,
608 zvol_tag, &os);
609 if (error)
610 return (error);
611
612 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize);
613 if (error) {
614 ASSERT(error == 0);
615 dmu_objset_disown(os, zvol_tag);
616 return (error);
617 }
618 zv->zv_objset = os;
619 error = dmu_bonus_hold(os, ZVOL_OBJ, zvol_tag, &zv->zv_dbuf);
620 if (error) {
621 dmu_objset_disown(os, zvol_tag);
622 return (error);
623 }
624 zv->zv_volsize = volsize;
625 zv->zv_zilog = zil_open(os, zvol_get_data);
626 zvol_size_changed(zv->zv_volsize, ddi_driver_major(zfs_dip),
627 zv->zv_minor);
628
629 VERIFY(dsl_prop_get_integer(zv->zv_name, "readonly", &readonly,
630 NULL) == 0);
631 if (readonly || dmu_objset_is_snapshot(os) ||
632 !spa_writeable(dmu_objset_spa(os)))
633 zv->zv_flags |= ZVOL_RDONLY;
634 else
635 zv->zv_flags &= ~ZVOL_RDONLY;
636 return (error);
637 }
638
639 void
640 zvol_last_close(zvol_state_t *zv)
641 {
642 zil_close(zv->zv_zilog);
643 zv->zv_zilog = NULL;
644 dmu_buf_rele(zv->zv_dbuf, zvol_tag);
645 zv->zv_dbuf = NULL;
646 dmu_objset_disown(zv->zv_objset, zvol_tag);
647 zv->zv_objset = NULL;
648 }
649
650 int
651 zvol_prealloc(zvol_state_t *zv)
652 {
653 objset_t *os = zv->zv_objset;
654 dmu_tx_t *tx;
655 uint64_t refd, avail, usedobjs, availobjs;
656 uint64_t resid = zv->zv_volsize;
657 uint64_t off = 0;
658
659 /* Check the space usage before attempting to allocate the space */
660 dmu_objset_space(os, &refd, &avail, &usedobjs, &availobjs);
661 if (avail < zv->zv_volsize)
662 return (ENOSPC);
663
664 /* Free old extents if they exist */
665 zvol_free_extents(zv);
666
667 while (resid != 0) {
668 int error;
669 uint64_t bytes = MIN(resid, SPA_MAXBLOCKSIZE);
670
671 tx = dmu_tx_create(os);
672 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes);
673 error = dmu_tx_assign(tx, TXG_WAIT);
674 if (error) {
675 dmu_tx_abort(tx);
676 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, off);
677 return (error);
678 }
679 dmu_prealloc(os, ZVOL_OBJ, off, bytes, tx);
680 dmu_tx_commit(tx);
681 off += bytes;
682 resid -= bytes;
683 }
684 txg_wait_synced(dmu_objset_pool(os), 0);
685
686 return (0);
687 }
688
689 int
690 zvol_update_volsize(objset_t *os, uint64_t volsize)
691 {
692 dmu_tx_t *tx;
693 int error;
694
695 ASSERT(MUTEX_HELD(&zfsdev_state_lock));
696
697 tx = dmu_tx_create(os);
698 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
699 error = dmu_tx_assign(tx, TXG_WAIT);
700 if (error) {
701 dmu_tx_abort(tx);
702 return (error);
703 }
704
705 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1,
706 &volsize, tx);
707 dmu_tx_commit(tx);
708
709 if (error == 0)
710 error = dmu_free_long_range(os,
711 ZVOL_OBJ, volsize, DMU_OBJECT_END);
712 return (error);
713 }
714
715 void
716 zvol_remove_minors(const char *name)
717 {
718 zvol_state_t *zv;
719 char *namebuf;
720 minor_t minor;
721
722 namebuf = kmem_zalloc(strlen(name) + 2, KM_SLEEP);
723 (void) strncpy(namebuf, name, strlen(name));
724 (void) strcat(namebuf, "/");
725 mutex_enter(&zfsdev_state_lock);
726 for (minor = 1; minor <= ZFSDEV_MAX_MINOR; minor++) {
727
728 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
729 if (zv == NULL)
730 continue;
731 if (strncmp(namebuf, zv->zv_name, strlen(namebuf)) == 0)
732 (void) zvol_remove_zv(zv);
733 }
734 kmem_free(namebuf, strlen(name) + 2);
735
736 mutex_exit(&zfsdev_state_lock);
737 }
738
739 int
740 zvol_set_volsize(const char *name, major_t maj, uint64_t volsize)
741 {
742 zvol_state_t *zv = NULL;
743 objset_t *os;
744 int error;
745 dmu_object_info_t doi;
746 uint64_t old_volsize = 0ULL;
747 uint64_t readonly;
748
749 mutex_enter(&zfsdev_state_lock);
750 zv = zvol_minor_lookup(name);
751 if ((error = dmu_objset_hold(name, FTAG, &os)) != 0) {
752 mutex_exit(&zfsdev_state_lock);
753 return (error);
754 }
755
756 if ((error = dmu_object_info(os, ZVOL_OBJ, &doi)) != 0 ||
757 (error = zvol_check_volsize(volsize,
758 doi.doi_data_block_size)) != 0)
759 goto out;
760
761 VERIFY(dsl_prop_get_integer(name, "readonly", &readonly,
762 NULL) == 0);
763 if (readonly) {
764 error = EROFS;
765 goto out;
766 }
767
768 error = zvol_update_volsize(os, volsize);
769 /*
770 * Reinitialize the dump area to the new size. If we
771 * failed to resize the dump area then restore it back to
772 * its original size.
773 */
774 if (zv && error == 0) {
775 if (zv->zv_flags & ZVOL_DUMPIFIED) {
776 old_volsize = zv->zv_volsize;
777 zv->zv_volsize = volsize;
778 if ((error = zvol_dumpify(zv)) != 0 ||
779 (error = dumpvp_resize()) != 0) {
780 (void) zvol_update_volsize(os, old_volsize);
781 zv->zv_volsize = old_volsize;
782 error = zvol_dumpify(zv);
783 }
784 }
785 if (error == 0) {
786 zv->zv_volsize = volsize;
787 zvol_size_changed(volsize, maj, zv->zv_minor);
788 }
789 }
790
791 /*
792 * Generate a LUN expansion event.
793 */
794 if (zv && error == 0) {
795 sysevent_id_t eid;
796 nvlist_t *attr;
797 char *physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
798
799 (void) snprintf(physpath, MAXPATHLEN, "%s%u", ZVOL_PSEUDO_DEV,
800 zv->zv_minor);
801
802 VERIFY(nvlist_alloc(&attr, NV_UNIQUE_NAME, KM_SLEEP) == 0);
803 VERIFY(nvlist_add_string(attr, DEV_PHYS_PATH, physpath) == 0);
804
805 (void) ddi_log_sysevent(zfs_dip, SUNW_VENDOR, EC_DEV_STATUS,
806 ESC_DEV_DLE, attr, &eid, DDI_SLEEP);
807
808 nvlist_free(attr);
809 kmem_free(physpath, MAXPATHLEN);
810 }
811
812 out:
813 dmu_objset_rele(os, FTAG);
814
815 mutex_exit(&zfsdev_state_lock);
816
817 return (error);
818 }
819
820 /*ARGSUSED*/
821 int
822 zvol_open(dev_t *devp, int flag, int otyp, cred_t *cr)
823 {
824 zvol_state_t *zv;
825 int err = 0;
826
827 mutex_enter(&zfsdev_state_lock);
828
829 zv = zfsdev_get_soft_state(getminor(*devp), ZSST_ZVOL);
830 if (zv == NULL) {
831 mutex_exit(&zfsdev_state_lock);
832 return (ENXIO);
833 }
834
835 if (zv->zv_total_opens == 0)
836 err = zvol_first_open(zv);
837 if (err) {
838 mutex_exit(&zfsdev_state_lock);
839 return (err);
840 }
841 if ((flag & FWRITE) && (zv->zv_flags & ZVOL_RDONLY)) {
842 err = EROFS;
843 goto out;
844 }
845 if (zv->zv_flags & ZVOL_EXCL) {
846 err = EBUSY;
847 goto out;
848 }
849 if (flag & FEXCL) {
850 if (zv->zv_total_opens != 0) {
851 err = EBUSY;
852 goto out;
853 }
854 zv->zv_flags |= ZVOL_EXCL;
855 }
856
857 if (zv->zv_open_count[otyp] == 0 || otyp == OTYP_LYR) {
858 zv->zv_open_count[otyp]++;
859 zv->zv_total_opens++;
860 }
861 mutex_exit(&zfsdev_state_lock);
862
863 return (err);
864 out:
865 if (zv->zv_total_opens == 0)
866 zvol_last_close(zv);
867 mutex_exit(&zfsdev_state_lock);
868 return (err);
869 }
870
871 /*ARGSUSED*/
872 int
873 zvol_close(dev_t dev, int flag, int otyp, cred_t *cr)
874 {
875 minor_t minor = getminor(dev);
876 zvol_state_t *zv;
877 int error = 0;
878
879 mutex_enter(&zfsdev_state_lock);
880
881 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
882 if (zv == NULL) {
883 mutex_exit(&zfsdev_state_lock);
884 return (ENXIO);
885 }
886
887 if (zv->zv_flags & ZVOL_EXCL) {
888 ASSERT(zv->zv_total_opens == 1);
889 zv->zv_flags &= ~ZVOL_EXCL;
890 }
891
892 /*
893 * If the open count is zero, this is a spurious close.
894 * That indicates a bug in the kernel / DDI framework.
895 */
896 ASSERT(zv->zv_open_count[otyp] != 0);
897 ASSERT(zv->zv_total_opens != 0);
898
899 /*
900 * You may get multiple opens, but only one close.
901 */
902 zv->zv_open_count[otyp]--;
903 zv->zv_total_opens--;
904
905 if (zv->zv_total_opens == 0)
906 zvol_last_close(zv);
907
908 mutex_exit(&zfsdev_state_lock);
909 return (error);
910 }
911
912 static void
913 zvol_get_done(zgd_t *zgd, int error)
914 {
915 if (zgd->zgd_db)
916 dmu_buf_rele(zgd->zgd_db, zgd);
917
918 zfs_range_unlock(zgd->zgd_rl);
919
920 if (error == 0 && zgd->zgd_bp)
921 zil_add_block(zgd->zgd_zilog, zgd->zgd_bp);
922
923 kmem_free(zgd, sizeof (zgd_t));
924 }
925
926 /*
927 * Get data to generate a TX_WRITE intent log record.
928 */
929 static int
930 zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio)
931 {
932 zvol_state_t *zv = arg;
933 objset_t *os = zv->zv_objset;
934 uint64_t object = ZVOL_OBJ;
935 uint64_t offset = lr->lr_offset;
936 uint64_t size = lr->lr_length; /* length of user data */
937 blkptr_t *bp = &lr->lr_blkptr;
938 dmu_buf_t *db;
939 zgd_t *zgd;
940 int error;
941
942 ASSERT(zio != NULL);
943 ASSERT(size != 0);
944
945 zgd = kmem_zalloc(sizeof (zgd_t), KM_SLEEP);
946 zgd->zgd_zilog = zv->zv_zilog;
947 zgd->zgd_rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER);
948
949 /*
950 * Write records come in two flavors: immediate and indirect.
951 * For small writes it's cheaper to store the data with the
952 * log record (immediate); for large writes it's cheaper to
953 * sync the data and get a pointer to it (indirect) so that
954 * we don't have to write the data twice.
955 */
956 if (buf != NULL) { /* immediate write */
957 error = dmu_read(os, object, offset, size, buf,
958 DMU_READ_NO_PREFETCH);
959 } else {
960 size = zv->zv_volblocksize;
961 offset = P2ALIGN(offset, size);
962 error = dmu_buf_hold(os, object, offset, zgd, &db,
963 DMU_READ_NO_PREFETCH);
964 if (error == 0) {
965 zgd->zgd_db = db;
966 zgd->zgd_bp = bp;
967
968 ASSERT(db->db_offset == offset);
969 ASSERT(db->db_size == size);
970
971 error = dmu_sync(zio, lr->lr_common.lrc_txg,
972 zvol_get_done, zgd);
973
974 if (error == 0)
975 return (0);
976 }
977 }
978
979 zvol_get_done(zgd, error);
980
981 return (error);
982 }
983
984 /*
985 * zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions.
986 *
987 * We store data in the log buffers if it's small enough.
988 * Otherwise we will later flush the data out via dmu_sync().
989 */
990 ssize_t zvol_immediate_write_sz = 32768;
991
992 static void
993 zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, offset_t off, ssize_t resid,
994 boolean_t sync)
995 {
996 uint32_t blocksize = zv->zv_volblocksize;
997 zilog_t *zilog = zv->zv_zilog;
998 boolean_t slogging;
999 ssize_t immediate_write_sz;
1000
1001 if (zil_replaying(zilog, tx))
1002 return;
1003
1004 immediate_write_sz = (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT)
1005 ? 0 : zvol_immediate_write_sz;
1006
1007 slogging = spa_has_slogs(zilog->zl_spa) &&
1008 (zilog->zl_logbias == ZFS_LOGBIAS_LATENCY);
1009
1010 while (resid) {
1011 itx_t *itx;
1012 lr_write_t *lr;
1013 ssize_t len;
1014 itx_wr_state_t write_state;
1015
1016 /*
1017 * Unlike zfs_log_write() we can be called with
1018 * upto DMU_MAX_ACCESS/2 (5MB) writes.
1019 */
1020 if (blocksize > immediate_write_sz && !slogging &&
1021 resid >= blocksize && off % blocksize == 0) {
1022 write_state = WR_INDIRECT; /* uses dmu_sync */
1023 len = blocksize;
1024 } else if (sync) {
1025 write_state = WR_COPIED;
1026 len = MIN(ZIL_MAX_LOG_DATA, resid);
1027 } else {
1028 write_state = WR_NEED_COPY;
1029 len = MIN(ZIL_MAX_LOG_DATA, resid);
1030 }
1031
1032 itx = zil_itx_create(TX_WRITE, sizeof (*lr) +
1033 (write_state == WR_COPIED ? len : 0));
1034 lr = (lr_write_t *)&itx->itx_lr;
1035 if (write_state == WR_COPIED && dmu_read(zv->zv_objset,
1036 ZVOL_OBJ, off, len, lr + 1, DMU_READ_NO_PREFETCH) != 0) {
1037 zil_itx_destroy(itx);
1038 itx = zil_itx_create(TX_WRITE, sizeof (*lr));
1039 lr = (lr_write_t *)&itx->itx_lr;
1040 write_state = WR_NEED_COPY;
1041 }
1042
1043 itx->itx_wr_state = write_state;
1044 if (write_state == WR_NEED_COPY)
1045 itx->itx_sod += len;
1046 lr->lr_foid = ZVOL_OBJ;
1047 lr->lr_offset = off;
1048 lr->lr_length = len;
1049 lr->lr_blkoff = 0;
1050 BP_ZERO(&lr->lr_blkptr);
1051
1052 itx->itx_private = zv;
1053 itx->itx_sync = sync;
1054
1055 zil_itx_assign(zilog, itx, tx);
1056
1057 off += len;
1058 resid -= len;
1059 }
1060 }
1061
1062 static int
1063 zvol_dumpio_vdev(vdev_t *vd, void *addr, uint64_t offset, uint64_t size,
1064 boolean_t doread, boolean_t isdump)
1065 {
1066 vdev_disk_t *dvd;
1067 int c;
1068 int numerrors = 0;
1069
1070 for (c = 0; c < vd->vdev_children; c++) {
1071 ASSERT(vd->vdev_ops == &vdev_mirror_ops ||
1072 vd->vdev_ops == &vdev_replacing_ops ||
1073 vd->vdev_ops == &vdev_spare_ops);
1074 int err = zvol_dumpio_vdev(vd->vdev_child[c],
1075 addr, offset, size, doread, isdump);
1076 if (err != 0) {
1077 numerrors++;
1078 } else if (doread) {
1079 break;
1080 }
1081 }
1082
1083 if (!vd->vdev_ops->vdev_op_leaf)
1084 return (numerrors < vd->vdev_children ? 0 : EIO);
1085
1086 if (doread && !vdev_readable(vd))
1087 return (EIO);
1088 else if (!doread && !vdev_writeable(vd))
1089 return (EIO);
1090
1091 dvd = vd->vdev_tsd;
1092 ASSERT3P(dvd, !=, NULL);
1093 offset += VDEV_LABEL_START_SIZE;
1094
1095 if (ddi_in_panic() || isdump) {
1096 ASSERT(!doread);
1097 if (doread)
1098 return (EIO);
1099 return (ldi_dump(dvd->vd_lh, addr, lbtodb(offset),
1100 lbtodb(size)));
1101 } else {
1102 return (vdev_disk_physio(dvd->vd_lh, addr, size, offset,
1103 doread ? B_READ : B_WRITE));
1104 }
1105 }
1106
1107 static int
1108 zvol_dumpio(zvol_state_t *zv, void *addr, uint64_t offset, uint64_t size,
1109 boolean_t doread, boolean_t isdump)
1110 {
1111 vdev_t *vd;
1112 int error;
1113 zvol_extent_t *ze;
1114 spa_t *spa = dmu_objset_spa(zv->zv_objset);
1115
1116 /* Must be sector aligned, and not stradle a block boundary. */
1117 if (P2PHASE(offset, DEV_BSIZE) || P2PHASE(size, DEV_BSIZE) ||
1118 P2BOUNDARY(offset, size, zv->zv_volblocksize)) {
1119 return (EINVAL);
1120 }
1121 ASSERT(size <= zv->zv_volblocksize);
1122
1123 /* Locate the extent this belongs to */
1124 ze = list_head(&zv->zv_extents);
1125 while (offset >= ze->ze_nblks * zv->zv_volblocksize) {
1126 offset -= ze->ze_nblks * zv->zv_volblocksize;
1127 ze = list_next(&zv->zv_extents, ze);
1128 }
1129
1130 if (!ddi_in_panic())
1131 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
1132
1133 vd = vdev_lookup_top(spa, DVA_GET_VDEV(&ze->ze_dva));
1134 offset += DVA_GET_OFFSET(&ze->ze_dva);
1135 error = zvol_dumpio_vdev(vd, addr, offset, size, doread, isdump);
1136
1137 if (!ddi_in_panic())
1138 spa_config_exit(spa, SCL_STATE, FTAG);
1139
1140 return (error);
1141 }
1142
1143 int
1144 zvol_strategy(buf_t *bp)
1145 {
1146 zfs_soft_state_t *zs = NULL;
1147 zvol_state_t *zv;
1148 uint64_t off, volsize;
1149 size_t resid;
1150 char *addr;
1151 objset_t *os;
1152 rl_t *rl;
1153 int error = 0;
1154 boolean_t doread = bp->b_flags & B_READ;
1155 boolean_t is_dump;
1156 boolean_t sync;
1157
1158 if (getminor(bp->b_edev) == 0) {
1159 error = EINVAL;
1160 } else {
1161 zs = ddi_get_soft_state(zfsdev_state, getminor(bp->b_edev));
1162 if (zs == NULL)
1163 error = ENXIO;
1164 else if (zs->zss_type != ZSST_ZVOL)
1165 error = EINVAL;
1166 }
1167
1168 if (error) {
1169 bioerror(bp, error);
1170 biodone(bp);
1171 return (0);
1172 }
1173
1174 zv = zs->zss_data;
1175
1176 if (!(bp->b_flags & B_READ) && (zv->zv_flags & ZVOL_RDONLY)) {
1177 bioerror(bp, EROFS);
1178 biodone(bp);
1179 return (0);
1180 }
1181
1182 off = ldbtob(bp->b_blkno);
1183 volsize = zv->zv_volsize;
1184
1185 os = zv->zv_objset;
1186 ASSERT(os != NULL);
1187
1188 bp_mapin(bp);
1189 addr = bp->b_un.b_addr;
1190 resid = bp->b_bcount;
1191
1192 if (resid > 0 && (off < 0 || off >= volsize)) {
1193 bioerror(bp, EIO);
1194 biodone(bp);
1195 return (0);
1196 }
1197
1198 is_dump = zv->zv_flags & ZVOL_DUMPIFIED;
1199 sync = ((!(bp->b_flags & B_ASYNC) &&
1200 !(zv->zv_flags & ZVOL_WCE)) ||
1201 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)) &&
1202 !doread && !is_dump;
1203
1204 /*
1205 * There must be no buffer changes when doing a dmu_sync() because
1206 * we can't change the data whilst calculating the checksum.
1207 */
1208 rl = zfs_range_lock(&zv->zv_znode, off, resid,
1209 doread ? RL_READER : RL_WRITER);
1210
1211 while (resid != 0 && off < volsize) {
1212 size_t size = MIN(resid, zvol_maxphys);
1213 if (is_dump) {
1214 size = MIN(size, P2END(off, zv->zv_volblocksize) - off);
1215 error = zvol_dumpio(zv, addr, off, size,
1216 doread, B_FALSE);
1217 } else if (doread) {
1218 error = dmu_read(os, ZVOL_OBJ, off, size, addr,
1219 DMU_READ_PREFETCH);
1220 } else {
1221 dmu_tx_t *tx = dmu_tx_create(os);
1222 dmu_tx_hold_write(tx, ZVOL_OBJ, off, size);
1223 error = dmu_tx_assign(tx, TXG_WAIT);
1224 if (error) {
1225 dmu_tx_abort(tx);
1226 } else {
1227 dmu_write(os, ZVOL_OBJ, off, size, addr, tx);
1228 zvol_log_write(zv, tx, off, size, sync);
1229 dmu_tx_commit(tx);
1230 }
1231 }
1232 if (error) {
1233 /* convert checksum errors into IO errors */
1234 if (error == ECKSUM)
1235 error = EIO;
1236 break;
1237 }
1238 off += size;
1239 addr += size;
1240 resid -= size;
1241 }
1242 zfs_range_unlock(rl);
1243
1244 if ((bp->b_resid = resid) == bp->b_bcount)
1245 bioerror(bp, off > volsize ? EINVAL : error);
1246
1247 if (sync)
1248 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1249 biodone(bp);
1250
1251 return (0);
1252 }
1253
1254 /*
1255 * Set the buffer count to the zvol maximum transfer.
1256 * Using our own routine instead of the default minphys()
1257 * means that for larger writes we write bigger buffers on X86
1258 * (128K instead of 56K) and flush the disk write cache less often
1259 * (every zvol_maxphys - currently 1MB) instead of minphys (currently
1260 * 56K on X86 and 128K on sparc).
1261 */
1262 void
1263 zvol_minphys(struct buf *bp)
1264 {
1265 if (bp->b_bcount > zvol_maxphys)
1266 bp->b_bcount = zvol_maxphys;
1267 }
1268
1269 int
1270 zvol_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblocks)
1271 {
1272 minor_t minor = getminor(dev);
1273 zvol_state_t *zv;
1274 int error = 0;
1275 uint64_t size;
1276 uint64_t boff;
1277 uint64_t resid;
1278
1279 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1280 if (zv == NULL)
1281 return (ENXIO);
1282
1283 boff = ldbtob(blkno);
1284 resid = ldbtob(nblocks);
1285
1286 VERIFY3U(boff + resid, <=, zv->zv_volsize);
1287
1288 while (resid) {
1289 size = MIN(resid, P2END(boff, zv->zv_volblocksize) - boff);
1290 error = zvol_dumpio(zv, addr, boff, size, B_FALSE, B_TRUE);
1291 if (error)
1292 break;
1293 boff += size;
1294 addr += size;
1295 resid -= size;
1296 }
1297
1298 return (error);
1299 }
1300
1301 /*ARGSUSED*/
1302 int
1303 zvol_read(dev_t dev, uio_t *uio, cred_t *cr)
1304 {
1305 minor_t minor = getminor(dev);
1306 zvol_state_t *zv;
1307 uint64_t volsize;
1308 rl_t *rl;
1309 int error = 0;
1310
1311 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1312 if (zv == NULL)
1313 return (ENXIO);
1314
1315 volsize = zv->zv_volsize;
1316 if (uio->uio_resid > 0 &&
1317 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize))
1318 return (EIO);
1319
1320 if (zv->zv_flags & ZVOL_DUMPIFIED) {
1321 error = physio(zvol_strategy, NULL, dev, B_READ,
1322 zvol_minphys, uio);
1323 return (error);
1324 }
1325
1326 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid,
1327 RL_READER);
1328 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) {
1329 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1);
1330
1331 /* don't read past the end */
1332 if (bytes > volsize - uio->uio_loffset)
1333 bytes = volsize - uio->uio_loffset;
1334
1335 error = dmu_read_uio(zv->zv_objset, ZVOL_OBJ, uio, bytes);
1336 if (error) {
1337 /* convert checksum errors into IO errors */
1338 if (error == ECKSUM)
1339 error = EIO;
1340 break;
1341 }
1342 }
1343 zfs_range_unlock(rl);
1344 return (error);
1345 }
1346
1347 /*ARGSUSED*/
1348 int
1349 zvol_write(dev_t dev, uio_t *uio, cred_t *cr)
1350 {
1351 minor_t minor = getminor(dev);
1352 zvol_state_t *zv;
1353 uint64_t volsize;
1354 rl_t *rl;
1355 int error = 0;
1356 boolean_t sync;
1357
1358 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1359 if (zv == NULL)
1360 return (ENXIO);
1361
1362 volsize = zv->zv_volsize;
1363 if (uio->uio_resid > 0 &&
1364 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize))
1365 return (EIO);
1366
1367 if (zv->zv_flags & ZVOL_DUMPIFIED) {
1368 error = physio(zvol_strategy, NULL, dev, B_WRITE,
1369 zvol_minphys, uio);
1370 return (error);
1371 }
1372
1373 sync = !(zv->zv_flags & ZVOL_WCE) ||
1374 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS);
1375
1376 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid,
1377 RL_WRITER);
1378 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) {
1379 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1);
1380 uint64_t off = uio->uio_loffset;
1381 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset);
1382
1383 if (bytes > volsize - off) /* don't write past the end */
1384 bytes = volsize - off;
1385
1386 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes);
1387 error = dmu_tx_assign(tx, TXG_WAIT);
1388 if (error) {
1389 dmu_tx_abort(tx);
1390 break;
1391 }
1392 error = dmu_write_uio_dbuf(zv->zv_dbuf, uio, bytes, tx);
1393 if (error == 0)
1394 zvol_log_write(zv, tx, off, bytes, sync);
1395 dmu_tx_commit(tx);
1396
1397 if (error)
1398 break;
1399 }
1400 zfs_range_unlock(rl);
1401 if (sync)
1402 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1403 return (error);
1404 }
1405
1406 int
1407 zvol_getefi(void *arg, int flag, uint64_t vs, uint8_t bs)
1408 {
1409 struct uuid uuid = EFI_RESERVED;
1410 efi_gpe_t gpe = { 0 };
1411 uint32_t crc;
1412 dk_efi_t efi;
1413 int length;
1414 char *ptr;
1415
1416 if (ddi_copyin(arg, &efi, sizeof (dk_efi_t), flag))
1417 return (EFAULT);
1418 ptr = (char *)(uintptr_t)efi.dki_data_64;
1419 length = efi.dki_length;
1420 /*
1421 * Some clients may attempt to request a PMBR for the
1422 * zvol. Currently this interface will return EINVAL to
1423 * such requests. These requests could be supported by
1424 * adding a check for lba == 0 and consing up an appropriate
1425 * PMBR.
1426 */
1427 if (efi.dki_lba < 1 || efi.dki_lba > 2 || length <= 0)
1428 return (EINVAL);
1429
1430 gpe.efi_gpe_StartingLBA = LE_64(34ULL);
1431 gpe.efi_gpe_EndingLBA = LE_64((vs >> bs) - 1);
1432 UUID_LE_CONVERT(gpe.efi_gpe_PartitionTypeGUID, uuid);
1433
1434 if (efi.dki_lba == 1) {
1435 efi_gpt_t gpt = { 0 };
1436
1437 gpt.efi_gpt_Signature = LE_64(EFI_SIGNATURE);
1438 gpt.efi_gpt_Revision = LE_32(EFI_VERSION_CURRENT);
1439 gpt.efi_gpt_HeaderSize = LE_32(sizeof (gpt));
1440 gpt.efi_gpt_MyLBA = LE_64(1ULL);
1441 gpt.efi_gpt_FirstUsableLBA = LE_64(34ULL);
1442 gpt.efi_gpt_LastUsableLBA = LE_64((vs >> bs) - 1);
1443 gpt.efi_gpt_PartitionEntryLBA = LE_64(2ULL);
1444 gpt.efi_gpt_NumberOfPartitionEntries = LE_32(1);
1445 gpt.efi_gpt_SizeOfPartitionEntry =
1446 LE_32(sizeof (efi_gpe_t));
1447 CRC32(crc, &gpe, sizeof (gpe), -1U, crc32_table);
1448 gpt.efi_gpt_PartitionEntryArrayCRC32 = LE_32(~crc);
1449 CRC32(crc, &gpt, sizeof (gpt), -1U, crc32_table);
1450 gpt.efi_gpt_HeaderCRC32 = LE_32(~crc);
1451 if (ddi_copyout(&gpt, ptr, MIN(sizeof (gpt), length),
1452 flag))
1453 return (EFAULT);
1454 ptr += sizeof (gpt);
1455 length -= sizeof (gpt);
1456 }
1457 if (length > 0 && ddi_copyout(&gpe, ptr, MIN(sizeof (gpe),
1458 length), flag))
1459 return (EFAULT);
1460 return (0);
1461 }
1462
1463 /*
1464 * BEGIN entry points to allow external callers access to the volume.
1465 */
1466 /*
1467 * Return the volume parameters needed for access from an external caller.
1468 * These values are invariant as long as the volume is held open.
1469 */
1470 int
1471 zvol_get_volume_params(minor_t minor, uint64_t *blksize,
1472 uint64_t *max_xfer_len, void **minor_hdl, void **objset_hdl, void **zil_hdl,
1473 void **rl_hdl, void **bonus_hdl)
1474 {
1475 zvol_state_t *zv;
1476
1477 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1478 if (zv == NULL)
1479 return (ENXIO);
1480 if (zv->zv_flags & ZVOL_DUMPIFIED)
1481 return (ENXIO);
1482
1483 ASSERT(blksize && max_xfer_len && minor_hdl &&
1484 objset_hdl && zil_hdl && rl_hdl && bonus_hdl);
1485
1486 *blksize = zv->zv_volblocksize;
1487 *max_xfer_len = (uint64_t)zvol_maxphys;
1488 *minor_hdl = zv;
1489 *objset_hdl = zv->zv_objset;
1490 *zil_hdl = zv->zv_zilog;
1491 *rl_hdl = &zv->zv_znode;
1492 *bonus_hdl = zv->zv_dbuf;
1493 return (0);
1494 }
1495
1496 /*
1497 * Return the current volume size to an external caller.
1498 * The size can change while the volume is open.
1499 */
1500 uint64_t
1501 zvol_get_volume_size(void *minor_hdl)
1502 {
1503 zvol_state_t *zv = minor_hdl;
1504
1505 return (zv->zv_volsize);
1506 }
1507
1508 /*
1509 * Return the current WCE setting to an external caller.
1510 * The WCE setting can change while the volume is open.
1511 */
1512 int
1513 zvol_get_volume_wce(void *minor_hdl)
1514 {
1515 zvol_state_t *zv = minor_hdl;
1516
1517 return ((zv->zv_flags & ZVOL_WCE) ? 1 : 0);
1518 }
1519
1520 /*
1521 * Entry point for external callers to zvol_log_write
1522 */
1523 void
1524 zvol_log_write_minor(void *minor_hdl, dmu_tx_t *tx, offset_t off, ssize_t resid,
1525 boolean_t sync)
1526 {
1527 zvol_state_t *zv = minor_hdl;
1528
1529 zvol_log_write(zv, tx, off, resid, sync);
1530 }
1531 /*
1532 * END entry points to allow external callers access to the volume.
1533 */
1534
1535 /*
1536 * Log a DKIOCFREE/free-long-range to the ZIL with TX_TRUNCATE.
1537 */
1538 static void
1539 zvol_log_truncate(zvol_state_t *zv, dmu_tx_t *tx, uint64_t off, uint64_t len,
1540 boolean_t sync)
1541 {
1542 itx_t *itx;
1543 lr_truncate_t *lr;
1544 zilog_t *zilog = zv->zv_zilog;
1545
1546 if (zil_replaying(zilog, tx))
1547 return;
1548
1549 itx = zil_itx_create(TX_TRUNCATE, sizeof (*lr));
1550 lr = (lr_truncate_t *)&itx->itx_lr;
1551 lr->lr_foid = ZVOL_OBJ;
1552 lr->lr_offset = off;
1553 lr->lr_length = len;
1554
1555 itx->itx_sync = sync;
1556 zil_itx_assign(zilog, itx, tx);
1557 }
1558
1559 /*
1560 * Dirtbag ioctls to support mkfs(1M) for UFS filesystems. See dkio(7I).
1561 * Also a dirtbag dkio ioctl for unmap/free-block functionality.
1562 */
1563 /*ARGSUSED*/
1564 int
1565 zvol_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp)
1566 {
1567 zvol_state_t *zv;
1568 struct dk_cinfo dki;
1569 struct dk_minfo dkm;
1570 struct dk_callback *dkc;
1571 int error = 0;
1572 rl_t *rl;
1573
1574 mutex_enter(&zfsdev_state_lock);
1575
1576 zv = zfsdev_get_soft_state(getminor(dev), ZSST_ZVOL);
1577
1578 if (zv == NULL) {
1579 mutex_exit(&zfsdev_state_lock);
1580 return (ENXIO);
1581 }
1582 ASSERT(zv->zv_total_opens > 0);
1583
1584 switch (cmd) {
1585
1586 case DKIOCINFO:
1587 bzero(&dki, sizeof (dki));
1588 (void) strcpy(dki.dki_cname, "zvol");
1589 (void) strcpy(dki.dki_dname, "zvol");
1590 dki.dki_ctype = DKC_UNKNOWN;
1591 dki.dki_unit = getminor(dev);
1592 dki.dki_maxtransfer = 1 << (SPA_MAXBLOCKSHIFT - zv->zv_min_bs);
1593 mutex_exit(&zfsdev_state_lock);
1594 if (ddi_copyout(&dki, (void *)arg, sizeof (dki), flag))
1595 error = EFAULT;
1596 return (error);
1597
1598 case DKIOCGMEDIAINFO:
1599 bzero(&dkm, sizeof (dkm));
1600 dkm.dki_lbsize = 1U << zv->zv_min_bs;
1601 dkm.dki_capacity = zv->zv_volsize >> zv->zv_min_bs;
1602 dkm.dki_media_type = DK_UNKNOWN;
1603 mutex_exit(&zfsdev_state_lock);
1604 if (ddi_copyout(&dkm, (void *)arg, sizeof (dkm), flag))
1605 error = EFAULT;
1606 return (error);
1607
1608 case DKIOCGETEFI:
1609 {
1610 uint64_t vs = zv->zv_volsize;
1611 uint8_t bs = zv->zv_min_bs;
1612
1613 mutex_exit(&zfsdev_state_lock);
1614 error = zvol_getefi((void *)arg, flag, vs, bs);
1615 return (error);
1616 }
1617
1618 case DKIOCFLUSHWRITECACHE:
1619 dkc = (struct dk_callback *)arg;
1620 mutex_exit(&zfsdev_state_lock);
1621 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1622 if ((flag & FKIOCTL) && dkc != NULL && dkc->dkc_callback) {
1623 (*dkc->dkc_callback)(dkc->dkc_cookie, error);
1624 error = 0;
1625 }
1626 return (error);
1627
1628 case DKIOCGETWCE:
1629 {
1630 int wce = (zv->zv_flags & ZVOL_WCE) ? 1 : 0;
1631 if (ddi_copyout(&wce, (void *)arg, sizeof (int),
1632 flag))
1633 error = EFAULT;
1634 break;
1635 }
1636 case DKIOCSETWCE:
1637 {
1638 int wce;
1639 if (ddi_copyin((void *)arg, &wce, sizeof (int),
1640 flag)) {
1641 error = EFAULT;
1642 break;
1643 }
1644 if (wce) {
1645 zv->zv_flags |= ZVOL_WCE;
1646 mutex_exit(&zfsdev_state_lock);
1647 } else {
1648 zv->zv_flags &= ~ZVOL_WCE;
1649 mutex_exit(&zfsdev_state_lock);
1650 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1651 }
1652 return (0);
1653 }
1654
1655 case DKIOCGGEOM:
1656 case DKIOCGVTOC:
1657 /*
1658 * commands using these (like prtvtoc) expect ENOTSUP
1659 * since we're emulating an EFI label
1660 */
1661 error = ENOTSUP;
1662 break;
1663
1664 case DKIOCDUMPINIT:
1665 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize,
1666 RL_WRITER);
1667 error = zvol_dumpify(zv);
1668 zfs_range_unlock(rl);
1669 break;
1670
1671 case DKIOCDUMPFINI:
1672 if (!(zv->zv_flags & ZVOL_DUMPIFIED))
1673 break;
1674 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize,
1675 RL_WRITER);
1676 error = zvol_dump_fini(zv);
1677 zfs_range_unlock(rl);
1678 break;
1679
1680 case DKIOCFREE:
1681 {
1682 dkioc_free_t df;
1683 dmu_tx_t *tx;
1684
1685 if (ddi_copyin((void *)arg, &df, sizeof (df), flag)) {
1686 error = EFAULT;
1687 break;
1688 }
1689
1690 /*
1691 * Apply Postel's Law to length-checking. If they overshoot,
1692 * just blank out until the end, if there's a need to blank
1693 * out anything.
1694 */
1695 if (df.df_start >= zv->zv_volsize)
1696 break; /* No need to do anything... */
1697 if (df.df_start + df.df_length > zv->zv_volsize)
1698 df.df_length = DMU_OBJECT_END;
1699
1700 rl = zfs_range_lock(&zv->zv_znode, df.df_start, df.df_length,
1701 RL_WRITER);
1702 tx = dmu_tx_create(zv->zv_objset);
1703 error = dmu_tx_assign(tx, TXG_WAIT);
1704 if (error != 0) {
1705 dmu_tx_abort(tx);
1706 } else {
1707 zvol_log_truncate(zv, tx, df.df_start,
1708 df.df_length, B_TRUE);
1709 dmu_tx_commit(tx);
1710 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ,
1711 df.df_start, df.df_length);
1712 }
1713
1714 zfs_range_unlock(rl);
1715
1716 if (error == 0) {
1717 /*
1718 * If the write-cache is disabled or 'sync' property
1719 * is set to 'always' then treat this as a synchronous
1720 * operation (i.e. commit to zil).
1721 */
1722 if (!(zv->zv_flags & ZVOL_WCE) ||
1723 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS))
1724 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1725
1726 /*
1727 * If the caller really wants synchronous writes, and
1728 * can't wait for them, don't return until the write
1729 * is done.
1730 */
1731 if (df.df_flags & DF_WAIT_SYNC) {
1732 txg_wait_synced(
1733 dmu_objset_pool(zv->zv_objset), 0);
1734 }
1735 }
1736 break;
1737 }
1738
1739 default:
1740 error = ENOTTY;
1741 break;
1742
1743 }
1744 mutex_exit(&zfsdev_state_lock);
1745 return (error);
1746 }
1747
1748 int
1749 zvol_busy(void)
1750 {
1751 return (zvol_minors != 0);
1752 }
1753
1754 void
1755 zvol_init(void)
1756 {
1757 VERIFY(ddi_soft_state_init(&zfsdev_state, sizeof (zfs_soft_state_t),
1758 1) == 0);
1759 mutex_init(&zfsdev_state_lock, NULL, MUTEX_DEFAULT, NULL);
1760 }
1761
1762 void
1763 zvol_fini(void)
1764 {
1765 mutex_destroy(&zfsdev_state_lock);
1766 ddi_soft_state_fini(&zfsdev_state);
1767 }
1768
1769 static int
1770 zvol_dump_init(zvol_state_t *zv, boolean_t resize)
1771 {
1772 dmu_tx_t *tx;
1773 int error = 0;
1774 objset_t *os = zv->zv_objset;
1775 nvlist_t *nv = NULL;
1776 uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset));
1777
1778 ASSERT(MUTEX_HELD(&zfsdev_state_lock));
1779 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 0,
1780 DMU_OBJECT_END);
1781 /* wait for dmu_free_long_range to actually free the blocks */
1782 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
1783
1784 tx = dmu_tx_create(os);
1785 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
1786 dmu_tx_hold_bonus(tx, ZVOL_OBJ);
1787 error = dmu_tx_assign(tx, TXG_WAIT);
1788 if (error) {
1789 dmu_tx_abort(tx);
1790 return (error);
1791 }
1792
1793 /*
1794 * If we are resizing the dump device then we only need to
1795 * update the refreservation to match the newly updated
1796 * zvolsize. Otherwise, we save off the original state of the
1797 * zvol so that we can restore them if the zvol is ever undumpified.
1798 */
1799 if (resize) {
1800 error = zap_update(os, ZVOL_ZAP_OBJ,
1801 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1,
1802 &zv->zv_volsize, tx);
1803 } else {
1804 uint64_t checksum, compress, refresrv, vbs, dedup;
1805
1806 error = dsl_prop_get_integer(zv->zv_name,
1807 zfs_prop_to_name(ZFS_PROP_COMPRESSION), &compress, NULL);
1808 error = error ? error : dsl_prop_get_integer(zv->zv_name,
1809 zfs_prop_to_name(ZFS_PROP_CHECKSUM), &checksum, NULL);
1810 error = error ? error : dsl_prop_get_integer(zv->zv_name,
1811 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &refresrv, NULL);
1812 error = error ? error : dsl_prop_get_integer(zv->zv_name,
1813 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &vbs, NULL);
1814 if (version >= SPA_VERSION_DEDUP) {
1815 error = error ? error :
1816 dsl_prop_get_integer(zv->zv_name,
1817 zfs_prop_to_name(ZFS_PROP_DEDUP), &dedup, NULL);
1818 }
1819
1820 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1821 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1,
1822 &compress, tx);
1823 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1824 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum, tx);
1825 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1826 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1,
1827 &refresrv, tx);
1828 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1829 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1,
1830 &vbs, tx);
1831 error = error ? error : dmu_object_set_blocksize(
1832 os, ZVOL_OBJ, SPA_MAXBLOCKSIZE, 0, tx);
1833 if (version >= SPA_VERSION_DEDUP) {
1834 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1835 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1,
1836 &dedup, tx);
1837 }
1838 if (error == 0)
1839 zv->zv_volblocksize = SPA_MAXBLOCKSIZE;
1840 }
1841 dmu_tx_commit(tx);
1842
1843 /*
1844 * We only need update the zvol's property if we are initializing
1845 * the dump area for the first time.
1846 */
1847 if (!resize) {
1848 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1849 VERIFY(nvlist_add_uint64(nv,
1850 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 0) == 0);
1851 VERIFY(nvlist_add_uint64(nv,
1852 zfs_prop_to_name(ZFS_PROP_COMPRESSION),
1853 ZIO_COMPRESS_OFF) == 0);
1854 VERIFY(nvlist_add_uint64(nv,
1855 zfs_prop_to_name(ZFS_PROP_CHECKSUM),
1856 ZIO_CHECKSUM_OFF) == 0);
1857 if (version >= SPA_VERSION_DEDUP) {
1858 VERIFY(nvlist_add_uint64(nv,
1859 zfs_prop_to_name(ZFS_PROP_DEDUP),
1860 ZIO_CHECKSUM_OFF) == 0);
1861 }
1862
1863 error = zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL,
1864 nv, NULL);
1865 nvlist_free(nv);
1866
1867 if (error)
1868 return (error);
1869 }
1870
1871 /* Allocate the space for the dump */
1872 error = zvol_prealloc(zv);
1873 return (error);
1874 }
1875
1876 static int
1877 zvol_dumpify(zvol_state_t *zv)
1878 {
1879 int error = 0;
1880 uint64_t dumpsize = 0;
1881 dmu_tx_t *tx;
1882 objset_t *os = zv->zv_objset;
1883
1884 if (zv->zv_flags & ZVOL_RDONLY)
1885 return (EROFS);
1886
1887 if (zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE,
1888 8, 1, &dumpsize) != 0 || dumpsize != zv->zv_volsize) {
1889 boolean_t resize = (dumpsize > 0);
1890
1891 if ((error = zvol_dump_init(zv, resize)) != 0) {
1892 (void) zvol_dump_fini(zv);
1893 return (error);
1894 }
1895 }
1896
1897 /*
1898 * Build up our lba mapping.
1899 */
1900 error = zvol_get_lbas(zv);
1901 if (error) {
1902 (void) zvol_dump_fini(zv);
1903 return (error);
1904 }
1905
1906 tx = dmu_tx_create(os);
1907 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
1908 error = dmu_tx_assign(tx, TXG_WAIT);
1909 if (error) {
1910 dmu_tx_abort(tx);
1911 (void) zvol_dump_fini(zv);
1912 return (error);
1913 }
1914
1915 zv->zv_flags |= ZVOL_DUMPIFIED;
1916 error = zap_update(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 8, 1,
1917 &zv->zv_volsize, tx);
1918 dmu_tx_commit(tx);
1919
1920 if (error) {
1921 (void) zvol_dump_fini(zv);
1922 return (error);
1923 }
1924
1925 txg_wait_synced(dmu_objset_pool(os), 0);
1926 return (0);
1927 }
1928
1929 static int
1930 zvol_dump_fini(zvol_state_t *zv)
1931 {
1932 dmu_tx_t *tx;
1933 objset_t *os = zv->zv_objset;
1934 nvlist_t *nv;
1935 int error = 0;
1936 uint64_t checksum, compress, refresrv, vbs, dedup;
1937 uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset));
1938
1939 /*
1940 * Attempt to restore the zvol back to its pre-dumpified state.
1941 * This is a best-effort attempt as it's possible that not all
1942 * of these properties were initialized during the dumpify process
1943 * (i.e. error during zvol_dump_init).
1944 */
1945
1946 tx = dmu_tx_create(os);
1947 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
1948 error = dmu_tx_assign(tx, TXG_WAIT);
1949 if (error) {
1950 dmu_tx_abort(tx);
1951 return (error);
1952 }
1953 (void) zap_remove(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, tx);
1954 dmu_tx_commit(tx);
1955
1956 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
1957 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum);
1958 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
1959 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, &compress);
1960 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
1961 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, &refresrv);
1962 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
1963 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, &vbs);
1964
1965 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1966 (void) nvlist_add_uint64(nv,
1967 zfs_prop_to_name(ZFS_PROP_CHECKSUM), checksum);
1968 (void) nvlist_add_uint64(nv,
1969 zfs_prop_to_name(ZFS_PROP_COMPRESSION), compress);
1970 (void) nvlist_add_uint64(nv,
1971 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), refresrv);
1972 if (version >= SPA_VERSION_DEDUP &&
1973 zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
1974 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, &dedup) == 0) {
1975 (void) nvlist_add_uint64(nv,
1976 zfs_prop_to_name(ZFS_PROP_DEDUP), dedup);
1977 }
1978 (void) zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL,
1979 nv, NULL);
1980 nvlist_free(nv);
1981
1982 zvol_free_extents(zv);
1983 zv->zv_flags &= ~ZVOL_DUMPIFIED;
1984 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, DMU_OBJECT_END);
1985 /* wait for dmu_free_long_range to actually free the blocks */
1986 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
1987 tx = dmu_tx_create(os);
1988 dmu_tx_hold_bonus(tx, ZVOL_OBJ);
1989 error = dmu_tx_assign(tx, TXG_WAIT);
1990 if (error) {
1991 dmu_tx_abort(tx);
1992 return (error);
1993 }
1994 if (dmu_object_set_blocksize(os, ZVOL_OBJ, vbs, 0, tx) == 0)
1995 zv->zv_volblocksize = vbs;
1996 dmu_tx_commit(tx);
1997
1998 return (0);
1999 }