1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
23 * Use is subject to license terms.
24 */
25
26/*
27 * ZFS volume emulation driver.
28 *
29 * Makes a DMU object look like a volume of arbitrary size, up to 2^64 bytes.
30 * Volumes are accessed through the symbolic links named:
31 *
32 * /dev/zvol/dsk/<pool_name>/<dataset_name>
33 * /dev/zvol/rdsk/<pool_name>/<dataset_name>
34 *
35 * These links are created by the /dev filesystem (sdev_zvolops.c).
36 * Volumes are persistent through reboot.  No user command needs to be
37 * run before opening and using a device.
38 */
39
40#include <sys/types.h>
41#include <sys/param.h>
42#include <sys/errno.h>
43#include <sys/uio.h>
44#include <sys/buf.h>
45#include <sys/modctl.h>
46#include <sys/open.h>
47#include <sys/kmem.h>
48#include <sys/conf.h>
49#include <sys/cmn_err.h>
50#include <sys/stat.h>
51#include <sys/zap.h>
52#include <sys/spa.h>
53#include <sys/zio.h>
54#include <sys/dmu_traverse.h>
55#include <sys/dnode.h>
56#include <sys/dsl_dataset.h>
57#include <sys/dsl_prop.h>
58#include <sys/dkio.h>
59#include <sys/efi_partition.h>
60#include <sys/byteorder.h>
61#include <sys/pathname.h>
62#include <sys/ddi.h>
63#include <sys/sunddi.h>
64#include <sys/crc32.h>
65#include <sys/dirent.h>
66#include <sys/policy.h>
67#include <sys/fs/zfs.h>
68#include <sys/zfs_ioctl.h>
69#include <sys/mkdev.h>
70#include <sys/zil.h>
71#include <sys/refcount.h>
72#include <sys/zfs_znode.h>
73#include <sys/zfs_rlock.h>
74#include <sys/vdev_disk.h>
75#include <sys/vdev_impl.h>
76#include <sys/zvol.h>
77#include <sys/disk.h>
78#include <sys/dkio.h>
79#include <sys/disklabel.h>
80
81#ifdef __NetBSD__
82#include <prop/proplib.h>
83#endif
84#include <sys/zil_impl.h>
85
86#include "zfs_namecheck.h"
87
88static void *zvol_state;
89static char *zvol_tag = "zvol_tag";
90
91#define	ZVOL_DUMPSIZE		"dumpsize"
92
93void	zvol_minphys(struct buf *);
94
95static struct	dkdriver zvol_dkdriver = { zvol_strategy, zvol_minphys };
96
97/*
98 * This lock protects the zvol_state structure from being modified
99 * while it's being used, e.g. an open that comes in before a create
100 * finishes.  It also protects temporary opens of the dataset so that,
101 * e.g., an open doesn't get a spurious EBUSY.
102 */
103static kmutex_t zvol_state_lock;
104static uint32_t zvol_minors;
105
106typedef struct zvol_extent {
107	list_node_t	ze_node;
108	dva_t		ze_dva;		/* dva associated with this extent */
109	uint64_t	ze_nblks;	/* number of blocks in extent */
110} zvol_extent_t;
111
112/*
113 * The in-core state of each volume.
114 */
115typedef struct zvol_state {
116	char		zv_name[MAXPATHLEN]; /* pool/dd name */
117	uint64_t	zv_volsize;	/* amount of space we advertise */
118	uint64_t	zv_volblocksize; /* volume block size */
119	minor_t		zv_minor;	/* minor number */
120	uint8_t		zv_min_bs;	/* minimum addressable block shift */
121	uint8_t		zv_flags;	/* readonly, dumpified, etc. */
122	objset_t	*zv_objset;	/* objset handle */
123	uint32_t	zv_open_count[OTYPCNT];	/* open counts */
124	uint32_t	zv_total_opens;	/* total open count */
125	zilog_t		*zv_zilog;	/* ZIL handle */
126	list_t		zv_extents;	/* List of extents for dump */
127	znode_t		zv_znode;	/* for range locking */
128#ifdef __NetBSD__
129	struct disk	zv_dk;		/* disk statistics */
130	kmutex_t	zv_dklock;	/* disk statistics */
131#endif
132} zvol_state_t;
133
134/*
135 * zvol specific flags
136 */
137#define	ZVOL_RDONLY	0x1
138#define	ZVOL_DUMPIFIED	0x2
139#define	ZVOL_EXCL	0x4
140#define	ZVOL_WCE	0x8
141
142/*
143 * zvol maximum transfer in one DMU tx.
144 */
145int zvol_maxphys = DMU_MAX_ACCESS/2;
146
147extern int zfs_set_prop_nvlist(const char *, zprop_source_t,
148    nvlist_t *, nvlist_t **);
149static int zvol_remove_zv(zvol_state_t *);
150static int zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio);
151static int zvol_dumpify(zvol_state_t *zv);
152static int zvol_dump_fini(zvol_state_t *zv);
153static int zvol_dump_init(zvol_state_t *zv, boolean_t resize);
154
155static void
156zvol_size_changed(zvol_state_t *zv)
157{
158	prop_dictionary_t disk_info, odisk_info, geom;
159	struct disk *disk;
160
161	disk = &zv->zv_dk;
162
163	disk_info = prop_dictionary_create();
164	geom = prop_dictionary_create();
165
166	prop_dictionary_set_cstring_nocopy(disk_info, "type", "ESDI");
167	prop_dictionary_set_uint64(geom, "sectors-per-unit", zv->zv_volsize);
168	prop_dictionary_set_uint32(geom, "sector-size",
169	    DEV_BSIZE /* XXX 512? */);
170	prop_dictionary_set_uint32(geom, "sectors-per-track", 32);
171	prop_dictionary_set_uint32(geom, "tracks-per-cylinder", 64);
172	prop_dictionary_set_uint32(geom, "cylinders-per-unit", zv->zv_volsize / 2048);
173	prop_dictionary_set(disk_info, "geometry", geom);
174	prop_object_release(geom);
175
176	odisk_info = disk->dk_info;
177	disk->dk_info = disk_info;
178
179	if (odisk_info != NULL)
180		prop_object_release(odisk_info);
181}
182
183int
184zvol_check_volsize(uint64_t volsize, uint64_t blocksize)
185{
186	if (volsize == 0)
187		return (EINVAL);
188
189	if (volsize % blocksize != 0)
190		return (EINVAL);
191
192#ifdef _ILP32
193	if (volsize - 1 > SPEC_MAXOFFSET_T)
194		return (EOVERFLOW);
195#endif
196	return (0);
197}
198
199int
200zvol_check_volblocksize(uint64_t volblocksize)
201{
202	if (volblocksize < SPA_MINBLOCKSIZE ||
203	    volblocksize > SPA_MAXBLOCKSIZE ||
204	    !ISP2(volblocksize))
205		return (EDOM);
206
207	return (0);
208}
209
210int
211zvol_get_stats(objset_t *os, nvlist_t *nv)
212{
213	int error;
214	dmu_object_info_t doi;
215	uint64_t val;
216
217	error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val);
218	if (error)
219		return (error);
220
221	dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val);
222
223	error = dmu_object_info(os, ZVOL_OBJ, &doi);
224
225	if (error == 0) {
226		dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE,
227		    doi.doi_data_block_size);
228	}
229
230	return (error);
231}
232
233/*
234 * Find a free minor number.
235 */
236static minor_t
237zvol_minor_alloc(void)
238{
239	minor_t minor;
240
241	ASSERT(MUTEX_HELD(&zvol_state_lock));
242
243	for (minor = 1; minor <= ZVOL_MAX_MINOR; minor++)
244		if (ddi_get_soft_state(zvol_state, minor) == NULL)
245			return (minor);
246
247	return (0);
248}
249
250static zvol_state_t *
251zvol_minor_lookup(const char *name)
252{
253	minor_t minor;
254	zvol_state_t *zv;
255
256	ASSERT(MUTEX_HELD(&zvol_state_lock));
257
258	for (minor = 1; minor <= ZVOL_MAX_MINOR; minor++) {
259		zv = ddi_get_soft_state(zvol_state, minor);
260		if (zv == NULL)
261			continue;
262		if (strcmp(zv->zv_name, name) == 0)
263			break;
264	}
265
266	return (zv);
267}
268
269/* extent mapping arg */
270struct maparg {
271	zvol_state_t	*ma_zv;
272	uint64_t	ma_blks;
273};
274
275/*ARGSUSED*/
276static int
277zvol_map_block(spa_t *spa, zilog_t *zilog, const blkptr_t *bp,
278    const zbookmark_t *zb, const dnode_phys_t *dnp, void *arg)
279{
280	struct maparg *ma = arg;
281	zvol_extent_t *ze;
282	int bs = ma->ma_zv->zv_volblocksize;
283
284	if (bp == NULL || zb->zb_object != ZVOL_OBJ || zb->zb_level != 0)
285		return (0);
286
287	VERIFY3U(ma->ma_blks, ==, zb->zb_blkid);
288	ma->ma_blks++;
289
290	/* Abort immediately if we have encountered gang blocks */
291	if (BP_IS_GANG(bp))
292		return (EFRAGS);
293
294	/*
295	 * See if the block is at the end of the previous extent.
296	 */
297	ze = list_tail(&ma->ma_zv->zv_extents);
298	if (ze &&
299	    DVA_GET_VDEV(BP_IDENTITY(bp)) == DVA_GET_VDEV(&ze->ze_dva) &&
300	    DVA_GET_OFFSET(BP_IDENTITY(bp)) ==
301	    DVA_GET_OFFSET(&ze->ze_dva) + ze->ze_nblks * bs) {
302		ze->ze_nblks++;
303		return (0);
304	}
305
306	dprintf_bp(bp, "%s", "next blkptr:");
307
308	/* start a new extent */
309	ze = kmem_zalloc(sizeof (zvol_extent_t), KM_SLEEP);
310	ze->ze_dva = bp->blk_dva[0];	/* structure assignment */
311	ze->ze_nblks = 1;
312	list_insert_tail(&ma->ma_zv->zv_extents, ze);
313	return (0);
314}
315
316static void
317zvol_free_extents(zvol_state_t *zv)
318{
319	zvol_extent_t *ze;
320
321	while (ze = list_head(&zv->zv_extents)) {
322		list_remove(&zv->zv_extents, ze);
323		kmem_free(ze, sizeof (zvol_extent_t));
324	}
325}
326
327static int
328zvol_get_lbas(zvol_state_t *zv)
329{
330	objset_t *os = zv->zv_objset;
331	struct maparg	ma;
332	int		err;
333
334	ma.ma_zv = zv;
335	ma.ma_blks = 0;
336	zvol_free_extents(zv);
337
338	/* commit any in-flight changes before traversing the dataset */
339	txg_wait_synced(dmu_objset_pool(os), 0);
340	err = traverse_dataset(dmu_objset_ds(os), 0,
341	    TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA, zvol_map_block, &ma);
342	if (err || ma.ma_blks != (zv->zv_volsize / zv->zv_volblocksize)) {
343		zvol_free_extents(zv);
344		return (err ? err : EIO);
345	}
346
347	return (0);
348}
349
350/* ARGSUSED */
351void
352zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx)
353{
354	zfs_creat_t *zct = arg;
355	nvlist_t *nvprops = zct->zct_props;
356	int error;
357	uint64_t volblocksize, volsize;
358
359	VERIFY(nvlist_lookup_uint64(nvprops,
360	    zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0);
361	if (nvlist_lookup_uint64(nvprops,
362	    zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0)
363		volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE);
364
365	/*
366	 * These properties must be removed from the list so the generic
367	 * property setting step won't apply to them.
368	 */
369	VERIFY(nvlist_remove_all(nvprops,
370	    zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0);
371	(void) nvlist_remove_all(nvprops,
372	    zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE));
373
374	error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize,
375	    DMU_OT_NONE, 0, tx);
376	ASSERT(error == 0);
377
378	error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP,
379	    DMU_OT_NONE, 0, tx);
380	ASSERT(error == 0);
381
382	error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx);
383	ASSERT(error == 0);
384}
385
386/*
387 * Replay a TX_WRITE ZIL transaction that didn't get committed
388 * after a system failure
389 */
390static int
391zvol_replay_write(zvol_state_t *zv, lr_write_t *lr, boolean_t byteswap)
392{
393	objset_t *os = zv->zv_objset;
394	char *data = (char *)(lr + 1);	/* data follows lr_write_t */
395	uint64_t offset, length;
396	dmu_tx_t *tx;
397	int error;
398
399	if (byteswap)
400		byteswap_uint64_array(lr, sizeof (*lr));
401
402	offset = lr->lr_offset;
403	length = lr->lr_length;
404
405	/* If it's a dmu_sync() block, write the whole block */
406	if (lr->lr_common.lrc_reclen == sizeof (lr_write_t)) {
407		uint64_t blocksize = BP_GET_LSIZE(&lr->lr_blkptr);
408		if (length < blocksize) {
409			offset -= offset % blocksize;
410			length = blocksize;
411		}
412	}
413
414	tx = dmu_tx_create(os);
415	dmu_tx_hold_write(tx, ZVOL_OBJ, offset, length);
416	error = dmu_tx_assign(tx, TXG_WAIT);
417	if (error) {
418		dmu_tx_abort(tx);
419	} else {
420		dmu_write(os, ZVOL_OBJ, offset, length, data, tx);
421		dmu_tx_commit(tx);
422	}
423
424	return (error);
425}
426
427/* ARGSUSED */
428static int
429zvol_replay_err(zvol_state_t *zv, lr_t *lr, boolean_t byteswap)
430{
431	return (ENOTSUP);
432}
433
434/*
435 * Callback vectors for replaying records.
436 * Only TX_WRITE is needed for zvol.
437 */
438zil_replay_func_t *zvol_replay_vector[TX_MAX_TYPE] = {
439	zvol_replay_err,	/* 0 no such transaction type */
440	zvol_replay_err,	/* TX_CREATE */
441	zvol_replay_err,	/* TX_MKDIR */
442	zvol_replay_err,	/* TX_MKXATTR */
443	zvol_replay_err,	/* TX_SYMLINK */
444	zvol_replay_err,	/* TX_REMOVE */
445	zvol_replay_err,	/* TX_RMDIR */
446	zvol_replay_err,	/* TX_LINK */
447	zvol_replay_err,	/* TX_RENAME */
448	zvol_replay_write,	/* TX_WRITE */
449	zvol_replay_err,	/* TX_TRUNCATE */
450	zvol_replay_err,	/* TX_SETATTR */
451	zvol_replay_err,	/* TX_ACL */
452	zvol_replay_err,	/* TX_CREATE_ACL */
453	zvol_replay_err,	/* TX_CREATE_ATTR */
454	zvol_replay_err,	/* TX_CREATE_ACL_ATTR */
455	zvol_replay_err,	/* TX_MKDIR_ACL */
456	zvol_replay_err,	/* TX_MKDIR_ATTR */
457	zvol_replay_err,	/* TX_MKDIR_ACL_ATTR */
458	zvol_replay_err,	/* TX_WRITE2 */
459};
460
461int
462zvol_name2minor(const char *name, minor_t *minor)
463{
464	zvol_state_t *zv;
465
466	mutex_enter(&zvol_state_lock);
467	zv = zvol_minor_lookup(name);
468	if (minor && zv)
469		*minor = zv->zv_minor;
470	mutex_exit(&zvol_state_lock);
471	return (zv ? 0 : -1);
472}
473
474/*
475 * Create a minor node (plus a whole lot more) for the specified volume.
476 */
477int
478zvol_create_minor(const char *name)
479{
480	zvol_state_t *zv;
481	objset_t *os;
482	dmu_object_info_t doi;
483	minor_t minor = 0;
484	vnode_t *vp = NULL;
485	char *devpath;
486	size_t devpathlen = strlen(ZVOL_FULL_DEV_DIR) + strlen(name) + 1;
487
488	int error;
489
490	mutex_enter(&zvol_state_lock);
491
492	if (zvol_minor_lookup(name) != NULL) {
493		mutex_exit(&zvol_state_lock);
494		return (EEXIST);
495	}
496
497	/* lie and say we're read-only */
498	error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, zvol_tag, &os);
499
500	if (error) {
501		mutex_exit(&zvol_state_lock);
502		return (error);
503	}
504
505	/*
506	 * If there's an existing /dev/zvol symlink, try to use the
507	 * same minor number we used last time.
508	 */
509	devpath = kmem_alloc(devpathlen, KM_SLEEP);
510
511	/* Get full path to ZFS volume disk device */
512	(void) sprintf(devpath, "%s/%s", ZVOL_FULL_DEV_DIR, name);
513
514	error = lookupname(devpath, UIO_SYSSPACE, NULL, &vp);
515
516	if (error == 0 && vp->v_type != VBLK) {
517		error = EINVAL;
518	}
519
520	if (error == 0) {
521		struct stat sb;
522		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
523		error = vn_stat(vp, &sb);
524		VOP_UNLOCK(vp);
525		if (error == 0) {
526			minor = getminor(sb.st_rdev);
527		}
528	}
529
530	if (vp != NULL)
531		VN_RELE(vp);
532
533	/*
534	 * If we found a minor but it's already in use, we must pick a new one.
535	 */
536	if (minor != 0 && ddi_get_soft_state(zvol_state, minor) != NULL)
537		minor = 0;
538
539	if (minor == 0)
540		minor = zvol_minor_alloc();
541
542	if (minor == 0) {
543		dmu_objset_disown(os, zvol_tag);
544		mutex_exit(&zvol_state_lock);
545		kmem_free(devpath, devpathlen);
546		return (ENXIO);
547	}
548
549	if (ddi_soft_state_zalloc(zvol_state, minor) != DDI_SUCCESS) {
550		dmu_objset_disown(os, zvol_tag);
551		mutex_exit(&zvol_state_lock);
552		kmem_free(devpath, devpathlen);
553		return (EAGAIN);
554	}
555	(void) ddi_prop_update_string(minor, zfs_dip, ZVOL_PROP_NAME,
556	    (char *)name);
557
558	if (ddi_create_minor_node(zfs_dip, (char *)name, S_IFCHR,
559	    minor, DDI_PSEUDO, 0) == DDI_FAILURE) {
560		ddi_soft_state_free(zvol_state, minor);
561		dmu_objset_disown(os, zvol_tag);
562		mutex_exit(&zvol_state_lock);
563		kmem_free(devpath, devpathlen);
564		return (EAGAIN);
565	}
566
567	if (ddi_create_minor_node(zfs_dip, (char *)name, S_IFBLK,
568	    minor, DDI_PSEUDO, 0) == DDI_FAILURE) {
569		ddi_remove_minor_node(zfs_dip, (char *)name);
570		ddi_soft_state_free(zvol_state, minor);
571		dmu_objset_disown(os, zvol_tag);
572		mutex_exit(&zvol_state_lock);
573		kmem_free(devpath, devpathlen);
574		return (EAGAIN);
575	}
576	zv = ddi_get_soft_state(zvol_state, minor);
577
578	(void) strlcpy(zv->zv_name, name, MAXPATHLEN);
579	zv->zv_min_bs = DEV_BSHIFT;
580	zv->zv_minor = minor;
581	zv->zv_objset = os;
582	if (dmu_objset_is_snapshot(os))
583		zv->zv_flags |= ZVOL_RDONLY;
584	mutex_init(&zv->zv_znode.z_range_lock, NULL, MUTEX_DEFAULT, NULL);
585	avl_create(&zv->zv_znode.z_range_avl, zfs_range_compare,
586	    sizeof (rl_t), offsetof(rl_t, r_node));
587	list_create(&zv->zv_extents, sizeof (zvol_extent_t),
588	    offsetof(zvol_extent_t, ze_node));
589	/* get and cache the blocksize */
590	error = dmu_object_info(os, ZVOL_OBJ, &doi);
591	ASSERT(error == 0);
592	zv->zv_volblocksize = doi.doi_data_block_size;
593
594	disk_init(&zv->zv_dk, name, &zvol_dkdriver);
595	disk_attach(&zv->zv_dk);
596	mutex_init(&zv->zv_dklock, NULL, MUTEX_DEFAULT, NULL);
597
598	zil_replay(os, zv, zvol_replay_vector);
599	dmu_objset_disown(os, zvol_tag);
600	zv->zv_objset = NULL;
601
602	zvol_size_changed(zv);
603
604	zvol_minors++;
605
606	mutex_exit(&zvol_state_lock);
607
608//	kmem_free(devpath, devpathlen);
609
610	return (0);
611}
612
613/*
614 * Remove minor node for the specified volume.
615 */
616static int
617zvol_remove_zv(zvol_state_t *zv)
618{
619	char nmbuf[20];
620
621	ASSERT(MUTEX_HELD(&zvol_state_lock));
622	if (zv->zv_total_opens != 0)
623		return (EBUSY);
624
625	(void) snprintf(nmbuf, sizeof (nmbuf), "%u,raw", zv->zv_minor);
626	ddi_remove_minor_node(zfs_dip, nmbuf);
627
628	(void) snprintf(nmbuf, sizeof (nmbuf), "%u", zv->zv_minor);
629	ddi_remove_minor_node(zfs_dip, nmbuf);
630
631	avl_destroy(&zv->zv_znode.z_range_avl);
632	mutex_destroy(&zv->zv_znode.z_range_lock);
633
634	ddi_soft_state_free(zvol_state, zv->zv_minor);
635
636	zvol_minors--;
637	return (0);
638}
639
640int
641zvol_remove_minor(const char *name)
642{
643	zvol_state_t *zv;
644	int rc;
645
646	mutex_enter(&zvol_state_lock);
647	if ((zv = zvol_minor_lookup(name)) == NULL) {
648		mutex_exit(&zvol_state_lock);
649		return (ENXIO);
650	}
651	rc = zvol_remove_zv(zv);
652	mutex_exit(&zvol_state_lock);
653	return (rc);
654}
655
656int
657zvol_first_open(zvol_state_t *zv)
658{
659	objset_t *os;
660	uint64_t volsize;
661	int error;
662	uint64_t readonly;
663
664	/* lie and say we're read-only */
665	error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, B_TRUE,
666	    zvol_tag, &os);
667	if (error)
668		return (error);
669
670	error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize);
671	if (error) {
672		ASSERT(error == 0);
673		dmu_objset_disown(os, zvol_tag);
674		return (error);
675	}
676	zv->zv_objset = os;
677	zv->zv_volsize = volsize;
678	zv->zv_zilog = zil_open(os, zvol_get_data);
679	zvol_size_changed(zv);
680
681	VERIFY(dsl_prop_get_integer(zv->zv_name, "readonly", &readonly,
682		NULL) == 0);
683	if (readonly || dmu_objset_is_snapshot(os))
684		zv->zv_flags |= ZVOL_RDONLY;
685	else
686		zv->zv_flags &= ~ZVOL_RDONLY;
687	return (error);
688}
689
690void
691zvol_last_close(zvol_state_t *zv)
692{
693	zil_close(zv->zv_zilog);
694	zv->zv_zilog = NULL;
695	dmu_objset_disown(zv->zv_objset, zvol_tag);
696	zv->zv_objset = NULL;
697#ifdef __NetBSD__
698	disk_detach(&zv->zv_dk);
699	disk_destroy(&zv->zv_dk);
700	mutex_destroy(&zv->zv_dklock);
701#endif
702	return;
703}
704
705int
706zvol_prealloc(zvol_state_t *zv)
707{
708	objset_t *os = zv->zv_objset;
709	dmu_tx_t *tx;
710	uint64_t refd, avail, usedobjs, availobjs;
711	uint64_t resid = zv->zv_volsize;
712	uint64_t off = 0;
713
714	/* Check the space usage before attempting to allocate the space */
715	dmu_objset_space(os, &refd, &avail, &usedobjs, &availobjs);
716	if (avail < zv->zv_volsize)
717		return (ENOSPC);
718
719	/* Free old extents if they exist */
720	zvol_free_extents(zv);
721
722	while (resid != 0) {
723		int error;
724		uint64_t bytes = MIN(resid, SPA_MAXBLOCKSIZE);
725
726		tx = dmu_tx_create(os);
727		dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes);
728		error = dmu_tx_assign(tx, TXG_WAIT);
729		if (error) {
730			dmu_tx_abort(tx);
731			(void) dmu_free_long_range(os, ZVOL_OBJ, 0, off);
732			return (error);
733		}
734		dmu_prealloc(os, ZVOL_OBJ, off, bytes, tx);
735		dmu_tx_commit(tx);
736		off += bytes;
737		resid -= bytes;
738	}
739	txg_wait_synced(dmu_objset_pool(os), 0);
740
741	return (0);
742}
743
744int
745zvol_update_volsize(objset_t *os, uint64_t volsize)
746{
747	dmu_tx_t *tx;
748	int error;
749
750	ASSERT(MUTEX_HELD(&zvol_state_lock));
751
752	tx = dmu_tx_create(os);
753	dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
754	error = dmu_tx_assign(tx, TXG_WAIT);
755	if (error) {
756		dmu_tx_abort(tx);
757		return (error);
758	}
759
760	error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1,
761	    &volsize, tx);
762	dmu_tx_commit(tx);
763
764	if (error == 0)
765		error = dmu_free_long_range(os,
766		    ZVOL_OBJ, volsize, DMU_OBJECT_END);
767	return (error);
768}
769
770void
771zvol_remove_minors(const char *name)
772{
773	zvol_state_t *zv;
774	char *namebuf;
775	minor_t minor;
776
777	namebuf = kmem_zalloc(strlen(name) + 2, KM_SLEEP);
778	(void) strncpy(namebuf, name, strlen(name));
779	(void) strcat(namebuf, "/");
780	mutex_enter(&zvol_state_lock);
781	for (minor = 1; minor <= ZVOL_MAX_MINOR; minor++) {
782
783		zv = ddi_get_soft_state(zvol_state, minor);
784		if (zv == NULL)
785			continue;
786		if (strncmp(namebuf, zv->zv_name, strlen(namebuf)) == 0)
787			(void) zvol_remove_zv(zv);
788	}
789	kmem_free(namebuf, strlen(name) + 2);
790
791	mutex_exit(&zvol_state_lock);
792}
793
794int
795zvol_set_volsize(const char *name, major_t maj, uint64_t volsize)
796{
797	zvol_state_t *zv = NULL;
798	objset_t *os;
799	int error;
800	dmu_object_info_t doi;
801	uint64_t old_volsize = 0ULL;
802	uint64_t readonly;
803
804	mutex_enter(&zvol_state_lock);
805	zv = zvol_minor_lookup(name);
806	if ((error = dmu_objset_hold(name, FTAG, &os)) != 0) {
807		mutex_exit(&zvol_state_lock);
808		return (error);
809	}
810
811	if ((error = dmu_object_info(os, ZVOL_OBJ, &doi)) != 0 ||
812	    (error = zvol_check_volsize(volsize,
813	    doi.doi_data_block_size)) != 0)
814		goto out;
815
816	VERIFY(dsl_prop_get_integer(name, "readonly", &readonly,
817	    NULL) == 0);
818	if (readonly) {
819		error = EROFS;
820		goto out;
821	}
822
823	error = zvol_update_volsize(os, volsize);
824
825#ifndef __NetBSD__
826	/*
827	 * Reinitialize the dump area to the new size. If we
828	 * failed to resize the dump area then restore it back to
829	 * its original size.
830	 */
831	if (zv && error == 0) {
832		if (zv->zv_flags & ZVOL_DUMPIFIED) {
833			old_volsize = zv->zv_volsize;
834			zv->zv_volsize = volsize;
835			if ((error = zvol_dumpify(zv)) != 0 ||
836			    (error = dumpvp_resize()) != 0) {
837				(void) zvol_update_volsize(os, old_volsize);
838				zv->zv_volsize = old_volsize;
839				error = zvol_dumpify(zv);
840			}
841		}
842		if (error == 0) {
843			zv->zv_volsize = volsize;
844			zvol_size_changed(volsize, maj, zv->zv_minor);
845		}
846	}
847#endif
848
849	/*
850	 * Generate a LUN expansion event.
851	 */
852	if (zv && error == 0) {
853		sysevent_id_t eid;
854		nvlist_t *attr;
855		char *physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
856
857		(void) snprintf(physpath, MAXPATHLEN, "%s%u", ZVOL_PSEUDO_DEV,
858		    zv->zv_minor);
859
860		VERIFY(nvlist_alloc(&attr, NV_UNIQUE_NAME, KM_SLEEP) == 0);
861		VERIFY(nvlist_add_string(attr, DEV_PHYS_PATH, physpath) == 0);
862
863		(void) ddi_log_sysevent(zfs_dip, SUNW_VENDOR, EC_DEV_STATUS,
864		    ESC_DEV_DLE, attr, &eid, DDI_SLEEP);
865
866		nvlist_free(attr);
867		kmem_free(physpath, MAXPATHLEN);
868	}
869
870out:
871	dmu_objset_rele(os, FTAG);
872
873	mutex_exit(&zvol_state_lock);
874
875	return (error);
876}
877
878/*ARGSUSED*/
879int
880zvol_open(dev_t *devp, int flag, int otyp, cred_t *cr)
881{
882	minor_t minor = getminor(*devp);
883	zvol_state_t *zv;
884	int err = 0;
885
886	if (minor == 0)			/* This is the control device */
887		return (0);
888
889	mutex_enter(&zvol_state_lock);
890
891	zv = ddi_get_soft_state(zvol_state, minor);
892	if (zv == NULL) {
893		mutex_exit(&zvol_state_lock);
894		return (ENXIO);
895	}
896
897	if (zv->zv_total_opens == 0)
898		err = zvol_first_open(zv);
899	if (err) {
900		mutex_exit(&zvol_state_lock);
901		return (err);
902	}
903	if ((flag & FWRITE) && (zv->zv_flags & ZVOL_RDONLY)) {
904		err = EROFS;
905		goto out;
906	}
907	if (zv->zv_flags & ZVOL_EXCL) {
908		err = EBUSY;
909		goto out;
910	}
911	if (flag & FEXCL) {
912		if (zv->zv_total_opens != 0) {
913			err = EBUSY;
914			goto out;
915		}
916		zv->zv_flags |= ZVOL_EXCL;
917	}
918
919	if (zv->zv_open_count[otyp] == 0 || otyp == OTYP_LYR) {
920		zv->zv_open_count[otyp]++;
921		zv->zv_total_opens++;
922	}
923	mutex_exit(&zvol_state_lock);
924
925	return (err);
926out:
927	if (zv->zv_total_opens == 0)
928		zvol_last_close(zv);
929	mutex_exit(&zvol_state_lock);
930	return (err);
931}
932
933/*ARGSUSED*/
934int
935zvol_close(dev_t dev, int flag, int otyp, cred_t *cr)
936{
937	minor_t minor = getminor(dev);
938	zvol_state_t *zv;
939	int error = 0;
940
941	if (minor == 0)		/* This is the control device */
942		return (0);
943
944	mutex_enter(&zvol_state_lock);
945
946	zv = ddi_get_soft_state(zvol_state, minor);
947	if (zv == NULL) {
948		mutex_exit(&zvol_state_lock);
949		return (ENXIO);
950	}
951
952	if (zv->zv_flags & ZVOL_EXCL) {
953		ASSERT(zv->zv_total_opens == 1);
954		zv->zv_flags &= ~ZVOL_EXCL;
955	}
956
957	/*
958	 * If the open count is zero, this is a spurious close.
959	 * That indicates a bug in the kernel / DDI framework.
960	 */
961	ASSERT(zv->zv_open_count[otyp] != 0);
962	ASSERT(zv->zv_total_opens != 0);
963
964	/*
965	 * You may get multiple opens, but only one close.
966	 */
967	zv->zv_open_count[otyp]--;
968	zv->zv_total_opens--;
969
970	if (zv->zv_total_opens == 0)
971		zvol_last_close(zv);
972
973	mutex_exit(&zvol_state_lock);
974	return (error);
975}
976
977static void
978zvol_get_done(zgd_t *zgd, int error)
979{
980	if (zgd->zgd_db)
981		dmu_buf_rele(zgd->zgd_db, zgd);
982
983	zfs_range_unlock(zgd->zgd_rl);
984
985	if (error == 0 && zgd->zgd_bp)
986		zil_add_block(zgd->zgd_zilog, zgd->zgd_bp);
987
988	kmem_free(zgd, sizeof (zgd_t));
989}
990
991/*
992 * Get data to generate a TX_WRITE intent log record.
993 */
994static int
995zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio)
996{
997	zvol_state_t *zv = arg;
998	objset_t *os = zv->zv_objset;
999	uint64_t object = ZVOL_OBJ;
1000	uint64_t offset = lr->lr_offset;
1001	uint64_t size = lr->lr_length;	/* length of user data */
1002	blkptr_t *bp = &lr->lr_blkptr;
1003	dmu_buf_t *db;
1004	zgd_t *zgd;
1005	int error;
1006
1007	ASSERT(zio != NULL);
1008	ASSERT(size != 0);
1009
1010	zgd = kmem_zalloc(sizeof (zgd_t), KM_SLEEP);
1011	zgd->zgd_zilog = zv->zv_zilog;
1012	zgd->zgd_rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER);
1013
1014	/*
1015	 * Write records come in two flavors: immediate and indirect.
1016	 * For small writes it's cheaper to store the data with the
1017	 * log record (immediate); for large writes it's cheaper to
1018	 * sync the data and get a pointer to it (indirect) so that
1019	 * we don't have to write the data twice.
1020	 */
1021	if (buf != NULL) {	/* immediate write */
1022		error = dmu_read(os, object, offset, size, buf,
1023		    DMU_READ_NO_PREFETCH);
1024	} else {
1025		size = zv->zv_volblocksize;
1026		offset = P2ALIGN(offset, size);
1027		error = dmu_buf_hold(os, object, offset, zgd, &db);
1028		if (error == 0) {
1029			zgd->zgd_db = db;
1030			zgd->zgd_bp = bp;
1031
1032			ASSERT(db->db_offset == offset);
1033			ASSERT(db->db_size == size);
1034
1035			error = dmu_sync(zio, lr->lr_common.lrc_txg,
1036			    zvol_get_done, zgd);
1037
1038			if (error == 0)
1039				return (0);
1040		}
1041	}
1042
1043	zvol_get_done(zgd, error);
1044
1045	return (error);
1046}
1047
1048/*
1049 * zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions.
1050 *
1051 * We store data in the log buffers if it's small enough.
1052 * Otherwise we will later flush the data out via dmu_sync().
1053 */
1054ssize_t zvol_immediate_write_sz = 32768;
1055
1056static void
1057zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, offset_t off, ssize_t resid,
1058    boolean_t sync)
1059{
1060	uint32_t blocksize = zv->zv_volblocksize;
1061	zilog_t *zilog = zv->zv_zilog;
1062	boolean_t slogging;
1063	ssize_t immediate_write_sz;
1064
1065	if (zil_disable)
1066		return;
1067
1068	if (zil_replaying(zilog, tx))
1069		return;
1070
1071	immediate_write_sz = (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT)
1072	    ? 0 : zvol_immediate_write_sz;
1073
1074	slogging = spa_has_slogs(zilog->zl_spa) &&
1075	    (zilog->zl_logbias == ZFS_LOGBIAS_LATENCY);
1076
1077	while (resid) {
1078		itx_t *itx;
1079		lr_write_t *lr;
1080		ssize_t len;
1081		itx_wr_state_t write_state;
1082
1083		/*
1084		 * Unlike zfs_log_write() we can be called with
1085		 * upto DMU_MAX_ACCESS/2 (5MB) writes.
1086		 */
1087		if (blocksize > immediate_write_sz && !slogging &&
1088		    resid >= blocksize && off % blocksize == 0) {
1089			write_state = WR_INDIRECT; /* uses dmu_sync */
1090			len = blocksize;
1091		} else if (sync) {
1092			write_state = WR_COPIED;
1093			len = MIN(ZIL_MAX_LOG_DATA, resid);
1094		} else {
1095			write_state = WR_NEED_COPY;
1096			len = MIN(ZIL_MAX_LOG_DATA, resid);
1097		}
1098
1099		itx = zil_itx_create(TX_WRITE, sizeof (*lr) +
1100		    (write_state == WR_COPIED ? len : 0));
1101		lr = (lr_write_t *)&itx->itx_lr;
1102		if (write_state == WR_COPIED && dmu_read(zv->zv_objset,
1103		    ZVOL_OBJ, off, len, lr + 1, DMU_READ_NO_PREFETCH) != 0) {
1104			zil_itx_destroy(itx);
1105			itx = zil_itx_create(TX_WRITE, sizeof (*lr));
1106			lr = (lr_write_t *)&itx->itx_lr;
1107			write_state = WR_NEED_COPY;
1108		}
1109
1110		itx->itx_wr_state = write_state;
1111		if (write_state == WR_NEED_COPY)
1112			itx->itx_sod += len;
1113		lr->lr_foid = ZVOL_OBJ;
1114		lr->lr_offset = off;
1115		lr->lr_length = len;
1116		lr->lr_blkoff = 0;
1117		BP_ZERO(&lr->lr_blkptr);
1118
1119		itx->itx_private = zv;
1120		itx->itx_sync = sync;
1121
1122		(void) zil_itx_assign(zilog, itx, tx);
1123
1124		off += len;
1125		resid -= len;
1126	}
1127}
1128
1129#ifndef __NetBSD__
1130static int
1131zvol_dumpio_vdev(vdev_t *vd, void *addr, uint64_t offset, uint64_t size,
1132    boolean_t doread, boolean_t isdump)
1133{
1134	vdev_disk_t *dvd;
1135	int c;
1136	int numerrors = 0;
1137
1138	for (c = 0; c < vd->vdev_children; c++) {
1139		ASSERT(vd->vdev_ops == &vdev_mirror_ops ||
1140		    vd->vdev_ops == &vdev_replacing_ops ||
1141		    vd->vdev_ops == &vdev_spare_ops);
1142		int err = zvol_dumpio_vdev(vd->vdev_child[c],
1143		    addr, offset, size, doread, isdump);
1144		if (err != 0) {
1145			numerrors++;
1146		} else if (doread) {
1147			break;
1148		}
1149	}
1150
1151	if (!vd->vdev_ops->vdev_op_leaf)
1152		return (numerrors < vd->vdev_children ? 0 : EIO);
1153
1154	if (doread && !vdev_readable(vd))
1155		return (EIO);
1156	else if (!doread && !vdev_writeable(vd))
1157		return (EIO);
1158
1159	dvd = vd->vdev_tsd;
1160	ASSERT3P(dvd, !=, NULL);
1161	offset += VDEV_LABEL_START_SIZE;
1162
1163	if (ddi_in_panic() || isdump) {
1164		ASSERT(!doread);
1165		if (doread)
1166			return (EIO);
1167		return (ldi_dump(dvd->vd_lh, addr, lbtodb(offset),
1168		    lbtodb(size)));
1169	} else {
1170		return (vdev_disk_physio(dvd->vd_lh, addr, size, offset,
1171		    doread ? B_READ : B_WRITE));
1172	}
1173}
1174
1175static int
1176zvol_dumpio(zvol_state_t *zv, void *addr, uint64_t offset, uint64_t size,
1177    boolean_t doread, boolean_t isdump)
1178{
1179	vdev_t *vd;
1180	int error;
1181	zvol_extent_t *ze;
1182	spa_t *spa = dmu_objset_spa(zv->zv_objset);
1183
1184	/* Must be sector aligned, and not stradle a block boundary. */
1185	if (P2PHASE(offset, DEV_BSIZE) || P2PHASE(size, DEV_BSIZE) ||
1186	    P2BOUNDARY(offset, size, zv->zv_volblocksize)) {
1187		return (EINVAL);
1188	}
1189	ASSERT(size <= zv->zv_volblocksize);
1190
1191	/* Locate the extent this belongs to */
1192	ze = list_head(&zv->zv_extents);
1193	while (offset >= ze->ze_nblks * zv->zv_volblocksize) {
1194		offset -= ze->ze_nblks * zv->zv_volblocksize;
1195		ze = list_next(&zv->zv_extents, ze);
1196	}
1197	spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
1198	vd = vdev_lookup_top(spa, DVA_GET_VDEV(&ze->ze_dva));
1199	offset += DVA_GET_OFFSET(&ze->ze_dva);
1200	error = zvol_dumpio_vdev(vd, addr, offset, size, doread, isdump);
1201	spa_config_exit(spa, SCL_STATE, FTAG);
1202	return (error);
1203}
1204#endif	/* __NetBSD__ */
1205
1206void
1207zvol_strategy(buf_t *bp)
1208{
1209	zvol_state_t *zv = ddi_get_soft_state(zvol_state, getminor(bp->b_edev));
1210	uint64_t off, volsize;
1211	size_t resid;
1212	char *addr;
1213	objset_t *os;
1214	rl_t *rl;
1215	int error = 0;
1216	boolean_t doread = bp->b_flags & B_READ;
1217	boolean_t is_dump = zv->zv_flags & ZVOL_DUMPIFIED;
1218	boolean_t sync;
1219
1220	if (zv == NULL) {
1221		bioerror(bp, ENXIO);
1222		biodone(bp);
1223		return;
1224	}
1225
1226	if (getminor(bp->b_edev) == 0) {
1227		bioerror(bp, EINVAL);
1228		biodone(bp);
1229		return;
1230	}
1231
1232	if (!(bp->b_flags & B_READ) && (zv->zv_flags & ZVOL_RDONLY)) {
1233		bioerror(bp, EROFS);
1234		biodone(bp);
1235		return;
1236	}
1237
1238	off = (uint64_t)bp->b_blkno * DEV_BSIZE;
1239	volsize = zv->zv_volsize;
1240
1241	os = zv->zv_objset;
1242	ASSERT(os != NULL);
1243
1244	addr = bp->b_data;
1245	resid = bp->b_bcount;
1246
1247	if (resid > 0 && (off < 0 || off >= volsize)) {
1248		bioerror(bp, EIO);
1249		biodone(bp);
1250		return;
1251	}
1252
1253	sync = !(bp->b_flags & B_ASYNC) && !doread && !is_dump &&
1254	    !(zv->zv_flags & ZVOL_WCE) && !zil_disable;
1255
1256	/*
1257	 * There must be no buffer changes when doing a dmu_sync() because
1258	 * we can't change the data whilst calculating the checksum.
1259	 */
1260	mutex_enter(&zv->zv_dklock);
1261	disk_busy(&zv->zv_dk);
1262	mutex_exit(&zv->zv_dklock);
1263
1264	rl = zfs_range_lock(&zv->zv_znode, off, resid,
1265	    doread ? RL_READER : RL_WRITER);
1266
1267	while (resid != 0 && off < volsize) {
1268		size_t size = MIN(resid, zvol_maxphys);
1269		if (is_dump) {
1270#ifdef __NetBSD__
1271			printf("XXXNETBSD zvol_strategy: how?");
1272#else
1273			size = MIN(size, P2END(off, zv->zv_volblocksize) - off);
1274			error = zvol_dumpio(zv, addr, off, size,
1275			    doread, B_FALSE);
1276#endif
1277		} else if (doread) {
1278			error = dmu_read(os, ZVOL_OBJ, off, size, addr,
1279			    DMU_READ_PREFETCH);
1280		} else {
1281			dmu_tx_t *tx = dmu_tx_create(os);
1282			dmu_tx_hold_write(tx, ZVOL_OBJ, off, size);
1283			error = dmu_tx_assign(tx, TXG_WAIT);
1284			if (error) {
1285				dmu_tx_abort(tx);
1286			} else {
1287				dmu_write(os, ZVOL_OBJ, off, size, addr, tx);
1288				zvol_log_write(zv, tx, off, size, sync);
1289				dmu_tx_commit(tx);
1290			}
1291		}
1292		if (error) {
1293			/* convert checksum errors into IO errors */
1294			if (error == ECKSUM)
1295				error = EIO;
1296			break;
1297		}
1298		off += size;
1299		addr += size;
1300		resid -= size;
1301	}
1302	zfs_range_unlock(rl);
1303
1304	if ((bp->b_resid = resid) == bp->b_bcount)
1305		bioerror(bp, off > volsize ? EINVAL : error);
1306
1307	if (sync)
1308		zil_commit(zv->zv_zilog, UINT64_MAX, ZVOL_OBJ);
1309	mutex_enter(&zv->zv_dklock);
1310	disk_unbusy(&zv->zv_dk, bp->b_bcount - bp->b_resid, doread);
1311	mutex_exit(&zv->zv_dklock);
1312	biodone(bp);
1313
1314	return;
1315}
1316
1317/*
1318 * Set the buffer count to the zvol maximum transfer.
1319 * Using our own routine instead of the default minphys()
1320 * means that for larger writes we write bigger buffers on X86
1321 * (128K instead of 56K) and flush the disk write cache less often
1322 * (every zvol_maxphys - currently 1MB) instead of minphys (currently
1323 * 56K on X86 and 128K on sparc).
1324 */
1325void
1326zvol_minphys(struct buf *bp)
1327{
1328	if (bp->b_bcount > zvol_maxphys)
1329		bp->b_bcount = zvol_maxphys;
1330}
1331
1332#ifndef __NetBSD__
1333int
1334zvol_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblocks)
1335{
1336	minor_t minor = getminor(dev);
1337	zvol_state_t *zv;
1338	int error = 0;
1339	uint64_t size;
1340	uint64_t boff;
1341	uint64_t resid;
1342
1343	if (minor == 0)			/* This is the control device */
1344		return (ENXIO);
1345
1346	zv = ddi_get_soft_state(zvol_state, minor);
1347	if (zv == NULL)
1348		return (ENXIO);
1349
1350	boff = ldbtob(blkno);
1351	resid = ldbtob(nblocks);
1352
1353	VERIFY3U(boff + resid, <=, zv->zv_volsize);
1354
1355	while (resid) {
1356		size = MIN(resid, P2END(boff, zv->zv_volblocksize) - boff);
1357		error = zvol_dumpio(zv, addr, boff, size, B_FALSE, B_TRUE);
1358		if (error)
1359			break;
1360		boff += size;
1361		addr += size;
1362		resid -= size;
1363	}
1364
1365	return (error);
1366}
1367#endif	/* !__NetBSD__ */
1368
1369/*ARGSUSED*/
1370int
1371zvol_read(dev_t dev, uio_t *uio, cred_t *cr)
1372{
1373	minor_t minor = getminor(dev);
1374	zvol_state_t *zv;
1375	uint64_t volsize;
1376	rl_t *rl;
1377	int error = 0;
1378
1379	if (minor == 0)			/* This is the control device */
1380		return (ENXIO);
1381
1382	zv = ddi_get_soft_state(zvol_state, minor);
1383	if (zv == NULL)
1384		return (ENXIO);
1385
1386	volsize = zv->zv_volsize;
1387	if (uio->uio_resid > 0 &&
1388	    (uio->uio_loffset < 0 || uio->uio_loffset >= volsize))
1389		return (EIO);
1390
1391	if (zv->zv_flags & ZVOL_DUMPIFIED) {
1392		error = physio(zvol_strategy, NULL, dev, B_READ,
1393		    zvol_minphys, uio);
1394		return (error);
1395	}
1396
1397	rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid,
1398	    RL_READER);
1399	while (uio->uio_resid > 0 && uio->uio_loffset < volsize) {
1400		uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1);
1401
1402		/* don't read past the end */
1403		if (bytes > volsize - uio->uio_loffset)
1404			bytes = volsize - uio->uio_loffset;
1405
1406		error =  dmu_read_uio(zv->zv_objset, ZVOL_OBJ, uio, bytes);
1407		if (error) {
1408			/* convert checksum errors into IO errors */
1409			if (error == ECKSUM)
1410				error = EIO;
1411			break;
1412		}
1413	}
1414	zfs_range_unlock(rl);
1415	return (error);
1416}
1417
1418/*ARGSUSED*/
1419int
1420zvol_write(dev_t dev, uio_t *uio, cred_t *cr)
1421{
1422	minor_t minor = getminor(dev);
1423	zvol_state_t *zv;
1424	uint64_t volsize;
1425	rl_t *rl;
1426	int error = 0;
1427	boolean_t sync;
1428
1429	if (minor == 0)			/* This is the control device */
1430		return (ENXIO);
1431
1432	zv = ddi_get_soft_state(zvol_state, minor);
1433	if (zv == NULL)
1434		return (ENXIO);
1435
1436	volsize = zv->zv_volsize;
1437	if (uio->uio_resid > 0 &&
1438	    (uio->uio_loffset < 0 || uio->uio_loffset >= volsize))
1439		return (EIO);
1440
1441	if (zv->zv_flags & ZVOL_DUMPIFIED) {
1442		error = physio(zvol_strategy, NULL, dev, B_WRITE,
1443		    zvol_minphys, uio);
1444		return (error);
1445	}
1446
1447	sync = !(zv->zv_flags & ZVOL_WCE) && !zil_disable;
1448
1449	rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid,
1450	    RL_WRITER);
1451	while (uio->uio_resid > 0 && uio->uio_loffset < volsize) {
1452		uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1);
1453		uint64_t off = uio->uio_loffset;
1454		dmu_tx_t *tx = dmu_tx_create(zv->zv_objset);
1455
1456		if (bytes > volsize - off)	/* don't write past the end */
1457			bytes = volsize - off;
1458
1459		dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes);
1460		error = dmu_tx_assign(tx, TXG_WAIT);
1461		if (error) {
1462			dmu_tx_abort(tx);
1463			break;
1464		}
1465		error = dmu_write_uio(zv->zv_objset, ZVOL_OBJ, uio, bytes, tx);
1466		if (error == 0)
1467			zvol_log_write(zv, tx, off, bytes, sync);
1468		dmu_tx_commit(tx);
1469
1470		if (error)
1471			break;
1472	}
1473	zfs_range_unlock(rl);
1474	if (sync)
1475		zil_commit(zv->zv_zilog, UINT64_MAX, ZVOL_OBJ);
1476	return (error);
1477}
1478
1479#ifdef __NetBSD__
1480
1481/*
1482 * Dirtbag ioctls to support newfs(1) for UFS filesystems.
1483 */
1484/*ARGSUSED*/
1485int
1486zvol_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp)
1487{
1488	zvol_state_t *zv;
1489	int error = 0;
1490
1491	mutex_enter(&zvol_state_lock);
1492
1493	zv = ddi_get_soft_state(zvol_state, getminor(dev));
1494
1495	if (zv == NULL) {
1496		mutex_exit(&zvol_state_lock);
1497		return (ENXIO);
1498	}
1499
1500	switch(cmd) {
1501	case DIOCGWEDGEINFO:
1502	{
1503		struct dkwedge_info *dkw = (void *) arg;
1504
1505		strlcpy(dkw->dkw_devname, zv->zv_name, 16);
1506		strlcpy(dkw->dkw_wname, zv->zv_name, MAXPATHLEN);
1507		strlcpy(dkw->dkw_parent, zv->zv_name, 16);
1508
1509		dkw->dkw_offset = 0;
1510		/* XXX NetBSD supports only DEV_BSIZE device block
1511		   size zv_volblocksize >> DEV_BSIZE*/
1512		dkw->dkw_size = (zv->zv_volsize / DEV_BSIZE);
1513		dprintf("dkw %"PRIu64" volsize %"PRIu64" volblock %"PRIu64" \n",
1514		    dkw->dkw_size, zv->zv_volsize, zv->zv_volblocksize);
1515		strcpy(dkw->dkw_ptype, DKW_PTYPE_FFS);
1516
1517		break;
1518	}
1519
1520	case DIOCGDISKINFO:
1521	{
1522		struct plistref *pref = (struct plistref *) arg;
1523
1524		if (zv->zv_dk.dk_info == NULL) {
1525			mutex_exit(&zvol_state_lock);
1526			return ENOTSUP;
1527		} else
1528			prop_dictionary_copyout_ioctl(pref, cmd,
1529			    zv->zv_dk.dk_info);
1530
1531		break;
1532	}
1533
1534	default:
1535		aprint_debug("unknown disk_ioctl called\n");
1536		error = ENOTTY;
1537		break;
1538	}
1539
1540	mutex_exit(&zvol_state_lock);
1541	return (error);
1542}
1543
1544#else	/* __NetBSD__ */
1545
1546int
1547zvol_getefi(void *arg, int flag, uint64_t vs, uint8_t bs)
1548{
1549	struct uuid uuid = EFI_RESERVED;
1550	efi_gpe_t gpe = { 0 };
1551	uint32_t crc;
1552	dk_efi_t efi;
1553	int length;
1554	char *ptr;
1555
1556	if (ddi_copyin(arg, &efi, sizeof (dk_efi_t), flag))
1557		return (EFAULT);
1558	ptr = (char *)(uintptr_t)efi.dki_data_64;
1559	length = efi.dki_length;
1560	/*
1561	 * Some clients may attempt to request a PMBR for the
1562	 * zvol.  Currently this interface will return EINVAL to
1563	 * such requests.  These requests could be supported by
1564	 * adding a check for lba == 0 and consing up an appropriate
1565	 * PMBR.
1566	 */
1567	if (efi.dki_lba < 1 || efi.dki_lba > 2 || length <= 0)
1568		return (EINVAL);
1569
1570	gpe.efi_gpe_StartingLBA = LE_64(34ULL);
1571	gpe.efi_gpe_EndingLBA = LE_64((vs >> bs) - 1);
1572	UUID_LE_CONVERT(gpe.efi_gpe_PartitionTypeGUID, uuid);
1573
1574	if (efi.dki_lba == 1) {
1575		efi_gpt_t gpt = { 0 };
1576
1577		gpt.efi_gpt_Signature = LE_64(EFI_SIGNATURE);
1578		gpt.efi_gpt_Revision = LE_32(EFI_VERSION_CURRENT);
1579		gpt.efi_gpt_HeaderSize = LE_32(sizeof (gpt));
1580		gpt.efi_gpt_MyLBA = LE_64(1ULL);
1581		gpt.efi_gpt_FirstUsableLBA = LE_64(34ULL);
1582		gpt.efi_gpt_LastUsableLBA = LE_64((vs >> bs) - 1);
1583		gpt.efi_gpt_PartitionEntryLBA = LE_64(2ULL);
1584		gpt.efi_gpt_NumberOfPartitionEntries = LE_32(1);
1585		gpt.efi_gpt_SizeOfPartitionEntry =
1586		    LE_32(sizeof (efi_gpe_t));
1587		CRC32(crc, &gpe, sizeof (gpe), -1U, crc32_table);
1588		gpt.efi_gpt_PartitionEntryArrayCRC32 = LE_32(~crc);
1589		CRC32(crc, &gpt, sizeof (gpt), -1U, crc32_table);
1590		gpt.efi_gpt_HeaderCRC32 = LE_32(~crc);
1591		if (ddi_copyout(&gpt, ptr, MIN(sizeof (gpt), length),
1592		    flag))
1593			return (EFAULT);
1594		ptr += sizeof (gpt);
1595		length -= sizeof (gpt);
1596	}
1597	if (length > 0 && ddi_copyout(&gpe, ptr, MIN(sizeof (gpe),
1598	    length), flag))
1599		return (EFAULT);
1600	return (0);
1601}
1602
1603/*
1604 * Dirtbag ioctls to support mkfs(1M) for UFS filesystems.  See dkio(7I).
1605 */
1606/*ARGSUSED*/
1607int
1608zvol_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp)
1609{
1610	zvol_state_t *zv;
1611	struct dk_cinfo dki;
1612	struct dk_minfo dkm;
1613	struct dk_callback *dkc;
1614	int error = 0;
1615	rl_t *rl;
1616
1617	mutex_enter(&zvol_state_lock);
1618
1619	zv = ddi_get_soft_state(zvol_state, getminor(dev));
1620
1621	if (zv == NULL) {
1622		mutex_exit(&zvol_state_lock);
1623		return (ENXIO);
1624	}
1625	ASSERT(zv->zv_total_opens > 0);
1626
1627	switch (cmd) {
1628
1629	case DKIOCINFO:
1630		bzero(&dki, sizeof (dki));
1631		(void) strcpy(dki.dki_cname, "zvol");
1632		(void) strcpy(dki.dki_dname, "zvol");
1633		dki.dki_ctype = DKC_UNKNOWN;
1634		dki.dki_unit = getminor(dev);
1635		dki.dki_maxtransfer = 1 << (SPA_MAXBLOCKSHIFT - zv->zv_min_bs);
1636		mutex_exit(&zvol_state_lock);
1637		if (ddi_copyout(&dki, (void *)arg, sizeof (dki), flag))
1638			error = EFAULT;
1639		return (error);
1640
1641	case DKIOCGMEDIAINFO:
1642		bzero(&dkm, sizeof (dkm));
1643		dkm.dki_lbsize = 1U << zv->zv_min_bs;
1644		dkm.dki_capacity = zv->zv_volsize >> zv->zv_min_bs;
1645		dkm.dki_media_type = DK_UNKNOWN;
1646		mutex_exit(&zvol_state_lock);
1647		if (ddi_copyout(&dkm, (void *)arg, sizeof (dkm), flag))
1648			error = EFAULT;
1649		return (error);
1650
1651	case DKIOCGETEFI:
1652		{
1653			uint64_t vs = zv->zv_volsize;
1654			uint8_t bs = zv->zv_min_bs;
1655
1656			mutex_exit(&zvol_state_lock);
1657			error = zvol_getefi((void *)arg, flag, vs, bs);
1658			return (error);
1659		}
1660
1661	case DKIOCFLUSHWRITECACHE:
1662		dkc = (struct dk_callback *)arg;
1663		mutex_exit(&zvol_state_lock);
1664		zil_commit(zv->zv_zilog, UINT64_MAX, ZVOL_OBJ);
1665		if ((flag & FKIOCTL) && dkc != NULL && dkc->dkc_callback) {
1666			(*dkc->dkc_callback)(dkc->dkc_cookie, error);
1667			error = 0;
1668		}
1669		return (error);
1670
1671	case DKIOCGETWCE:
1672		{
1673			int wce = (zv->zv_flags & ZVOL_WCE) ? 1 : 0;
1674			if (ddi_copyout(&wce, (void *)arg, sizeof (int),
1675			    flag))
1676				error = EFAULT;
1677			break;
1678		}
1679	case DKIOCSETWCE:
1680		{
1681			int wce;
1682			if (ddi_copyin((void *)arg, &wce, sizeof (int),
1683			    flag)) {
1684				error = EFAULT;
1685				break;
1686			}
1687			if (wce) {
1688				zv->zv_flags |= ZVOL_WCE;
1689				mutex_exit(&zvol_state_lock);
1690			} else {
1691				zv->zv_flags &= ~ZVOL_WCE;
1692				mutex_exit(&zvol_state_lock);
1693				zil_commit(zv->zv_zilog, UINT64_MAX, ZVOL_OBJ);
1694			}
1695			return (0);
1696		}
1697
1698	case DKIOCGGEOM:
1699	case DKIOCGVTOC:
1700		/*
1701		 * commands using these (like prtvtoc) expect ENOTSUP
1702		 * since we're emulating an EFI label
1703		 */
1704		error = ENOTSUP;
1705		break;
1706
1707	case DKIOCDUMPINIT:
1708		rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize,
1709		    RL_WRITER);
1710		error = zvol_dumpify(zv);
1711		zfs_range_unlock(rl);
1712		break;
1713
1714	case DKIOCDUMPFINI:
1715		if (!(zv->zv_flags & ZVOL_DUMPIFIED))
1716			break;
1717		rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize,
1718		    RL_WRITER);
1719		error = zvol_dump_fini(zv);
1720		zfs_range_unlock(rl);
1721		break;
1722
1723	default:
1724		error = ENOTTY;
1725		break;
1726
1727	}
1728	mutex_exit(&zvol_state_lock);
1729	return (error);
1730}
1731
1732#endif	/* __NetBSD__ */
1733
1734int
1735zvol_busy(void)
1736{
1737	return (zvol_minors != 0);
1738}
1739
1740void
1741zvol_init(void)
1742{
1743	VERIFY(ddi_soft_state_init(&zvol_state, sizeof (zvol_state_t), 1) == 0);
1744	mutex_init(&zvol_state_lock, NULL, MUTEX_DEFAULT, NULL);
1745}
1746
1747void
1748zvol_fini(void)
1749{
1750	mutex_destroy(&zvol_state_lock);
1751	ddi_soft_state_fini(&zvol_state);
1752}
1753
1754#ifndef __NetBSD__
1755static int
1756zvol_dump_init(zvol_state_t *zv, boolean_t resize)
1757{
1758	dmu_tx_t *tx;
1759	int error = 0;
1760	objset_t *os = zv->zv_objset;
1761	nvlist_t *nv = NULL;
1762	uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset));
1763
1764	ASSERT(MUTEX_HELD(&zvol_state_lock));
1765	error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 0,
1766	    DMU_OBJECT_END);
1767	/* wait for dmu_free_long_range to actually free the blocks */
1768	txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
1769
1770	tx = dmu_tx_create(os);
1771	dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
1772	dmu_tx_hold_bonus(tx, ZVOL_OBJ);
1773	error = dmu_tx_assign(tx, TXG_WAIT);
1774	if (error) {
1775		dmu_tx_abort(tx);
1776		return (error);
1777	}
1778
1779	/*
1780	 * If we are resizing the dump device then we only need to
1781	 * update the refreservation to match the newly updated
1782	 * zvolsize. Otherwise, we save off the original state of the
1783	 * zvol so that we can restore them if the zvol is ever undumpified.
1784	 */
1785	if (resize) {
1786		error = zap_update(os, ZVOL_ZAP_OBJ,
1787		    zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1,
1788		    &zv->zv_volsize, tx);
1789	} else {
1790		uint64_t checksum, compress, refresrv, vbs, dedup;
1791
1792		error = dsl_prop_get_integer(zv->zv_name,
1793		    zfs_prop_to_name(ZFS_PROP_COMPRESSION), &compress, NULL);
1794		error = error ? error : dsl_prop_get_integer(zv->zv_name,
1795		    zfs_prop_to_name(ZFS_PROP_CHECKSUM), &checksum, NULL);
1796		error = error ? error : dsl_prop_get_integer(zv->zv_name,
1797		    zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &refresrv, NULL);
1798		error = error ? error : dsl_prop_get_integer(zv->zv_name,
1799		    zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &vbs, NULL);
1800		if (version >= SPA_VERSION_DEDUP) {
1801			error = error ? error :
1802			    dsl_prop_get_integer(zv->zv_name,
1803			    zfs_prop_to_name(ZFS_PROP_DEDUP), &dedup, NULL);
1804		}
1805
1806		error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1807		    zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1,
1808		    &compress, tx);
1809		error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1810		    zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum, tx);
1811		error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1812		    zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1,
1813		    &refresrv, tx);
1814		error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1815		    zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1,
1816		    &vbs, tx);
1817		error = error ? error : dmu_object_set_blocksize(
1818		    os, ZVOL_OBJ, SPA_MAXBLOCKSIZE, 0, tx);
1819		if (version >= SPA_VERSION_DEDUP) {
1820			error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1821			    zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1,
1822			    &dedup, tx);
1823		}
1824		if (error == 0)
1825			zv->zv_volblocksize = SPA_MAXBLOCKSIZE;
1826	}
1827	dmu_tx_commit(tx);
1828
1829	/*
1830	 * We only need update the zvol's property if we are initializing
1831	 * the dump area for the first time.
1832	 */
1833	if (!resize) {
1834		VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1835		VERIFY(nvlist_add_uint64(nv,
1836		    zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 0) == 0);
1837		VERIFY(nvlist_add_uint64(nv,
1838		    zfs_prop_to_name(ZFS_PROP_COMPRESSION),
1839		    ZIO_COMPRESS_OFF) == 0);
1840		VERIFY(nvlist_add_uint64(nv,
1841		    zfs_prop_to_name(ZFS_PROP_CHECKSUM),
1842		    ZIO_CHECKSUM_OFF) == 0);
1843		if (version >= SPA_VERSION_DEDUP) {
1844			VERIFY(nvlist_add_uint64(nv,
1845			    zfs_prop_to_name(ZFS_PROP_DEDUP),
1846			    ZIO_CHECKSUM_OFF) == 0);
1847		}
1848
1849		error = zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL,
1850		    nv, NULL);
1851		nvlist_free(nv);
1852
1853		if (error)
1854			return (error);
1855	}
1856
1857	/* Allocate the space for the dump */
1858	error = zvol_prealloc(zv);
1859	return (error);
1860}
1861
1862static int
1863zvol_dumpify(zvol_state_t *zv)
1864{
1865	int error = 0;
1866	uint64_t dumpsize = 0;
1867	dmu_tx_t *tx;
1868	objset_t *os = zv->zv_objset;
1869
1870	if (zv->zv_flags & ZVOL_RDONLY)
1871		return (EROFS);
1872
1873	if (zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE,
1874	    8, 1, &dumpsize) != 0 || dumpsize != zv->zv_volsize) {
1875		boolean_t resize = (dumpsize > 0) ? B_TRUE : B_FALSE;
1876
1877		if ((error = zvol_dump_init(zv, resize)) != 0) {
1878			(void) zvol_dump_fini(zv);
1879			return (error);
1880		}
1881	}
1882
1883	/*
1884	 * Build up our lba mapping.
1885	 */
1886	error = zvol_get_lbas(zv);
1887	if (error) {
1888		(void) zvol_dump_fini(zv);
1889		return (error);
1890	}
1891
1892	tx = dmu_tx_create(os);
1893	dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
1894	error = dmu_tx_assign(tx, TXG_WAIT);
1895	if (error) {
1896		dmu_tx_abort(tx);
1897		(void) zvol_dump_fini(zv);
1898		return (error);
1899	}
1900
1901	zv->zv_flags |= ZVOL_DUMPIFIED;
1902	error = zap_update(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 8, 1,
1903	    &zv->zv_volsize, tx);
1904	dmu_tx_commit(tx);
1905
1906	if (error) {
1907		(void) zvol_dump_fini(zv);
1908		return (error);
1909	}
1910
1911	txg_wait_synced(dmu_objset_pool(os), 0);
1912	return (0);
1913}
1914
1915static int
1916zvol_dump_fini(zvol_state_t *zv)
1917{
1918	dmu_tx_t *tx;
1919	objset_t *os = zv->zv_objset;
1920	nvlist_t *nv;
1921	int error = 0;
1922	uint64_t checksum, compress, refresrv, vbs, dedup;
1923	uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset));
1924
1925	/*
1926	 * Attempt to restore the zvol back to its pre-dumpified state.
1927	 * This is a best-effort attempt as it's possible that not all
1928	 * of these properties were initialized during the dumpify process
1929	 * (i.e. error during zvol_dump_init).
1930	 */
1931
1932	tx = dmu_tx_create(os);
1933	dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
1934	error = dmu_tx_assign(tx, TXG_WAIT);
1935	if (error) {
1936		dmu_tx_abort(tx);
1937		return (error);
1938	}
1939	(void) zap_remove(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, tx);
1940	dmu_tx_commit(tx);
1941
1942	(void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
1943	    zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum);
1944	(void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
1945	    zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, &compress);
1946	(void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
1947	    zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, &refresrv);
1948	(void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
1949	    zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, &vbs);
1950
1951	VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1952	(void) nvlist_add_uint64(nv,
1953	    zfs_prop_to_name(ZFS_PROP_CHECKSUM), checksum);
1954	(void) nvlist_add_uint64(nv,
1955	    zfs_prop_to_name(ZFS_PROP_COMPRESSION), compress);
1956	(void) nvlist_add_uint64(nv,
1957	    zfs_prop_to_name(ZFS_PROP_REFRESERVATION), refresrv);
1958	if (version >= SPA_VERSION_DEDUP &&
1959	    zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
1960	    zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, &dedup) == 0) {
1961		(void) nvlist_add_uint64(nv,
1962		    zfs_prop_to_name(ZFS_PROP_DEDUP), dedup);
1963	}
1964	(void) zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL,
1965	    nv, NULL);
1966	nvlist_free(nv);
1967
1968	zvol_free_extents(zv);
1969	zv->zv_flags &= ~ZVOL_DUMPIFIED;
1970	(void) dmu_free_long_range(os, ZVOL_OBJ, 0, DMU_OBJECT_END);
1971	/* wait for dmu_free_long_range to actually free the blocks */
1972	txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
1973	tx = dmu_tx_create(os);
1974	dmu_tx_hold_bonus(tx, ZVOL_OBJ);
1975	error = dmu_tx_assign(tx, TXG_WAIT);
1976	if (error) {
1977		dmu_tx_abort(tx);
1978		return (error);
1979	}
1980	if (dmu_object_set_blocksize(os, ZVOL_OBJ, vbs, 0, tx) == 0)
1981		zv->zv_volblocksize = vbs;
1982	dmu_tx_commit(tx);
1983
1984	return (0);
1985}
1986#endif	/* !__NetBSD__ */
1987