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.
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.
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]
22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Copyright (c) 2006-2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
25 * All rights reserved.
26 * Copyright (c) 2013 by Delphix. All rights reserved.
27 * Copyright (c) 2013, Joyent, Inc. All rights reserved.
30 /* Portions Copyright 2010 Robert Milkowski */
31 /* Portions Copyright 2011 Martin Matuska <mm@FreeBSD.org> */
34 * ZFS volume emulation driver.
36 * Makes a DMU object look like a volume of arbitrary size, up to 2^64 bytes.
37 * Volumes are accessed through the symbolic links named:
39 * /dev/zvol/dsk/<pool_name>/<dataset_name>
40 * /dev/zvol/rdsk/<pool_name>/<dataset_name>
42 * These links are created by the /dev filesystem (sdev_zvolops.c).
43 * Volumes are persistent through reboot. No user command needs to be
44 * run before opening and using a device.
47 * On FreeBSD ZVOLs are simply GEOM providers like any other storage device
51 #include <sys/types.h>
52 #include <sys/param.h>
53 #include <sys/kernel.h>
54 #include <sys/errno.h>
60 #include <sys/cmn_err.h>
64 #include <sys/spa_impl.h>
66 #include <sys/dmu_traverse.h>
67 #include <sys/dnode.h>
68 #include <sys/dsl_dataset.h>
69 #include <sys/dsl_prop.h>
71 #include <sys/byteorder.h>
72 #include <sys/sunddi.h>
73 #include <sys/dirent.h>
74 #include <sys/policy.h>
75 #include <sys/fs/zfs.h>
76 #include <sys/zfs_ioctl.h>
78 #include <sys/refcount.h>
79 #include <sys/zfs_znode.h>
80 #include <sys/zfs_rlock.h>
81 #include <sys/vdev_impl.h>
82 #include <sys/vdev_raidz.h>
84 #include <sys/zil_impl.h>
86 #include <sys/dmu_tx.h>
87 #include <sys/zfeature.h>
88 #include <sys/zio_checksum.h>
90 #include <geom/geom.h>
92 #include "zfs_namecheck.h"
94 struct g_class zfs_zvol_class = {
99 DECLARE_GEOM_CLASS(zfs_zvol_class, zfs_zvol);
102 static char *zvol_tag = "zvol_tag";
104 #define ZVOL_DUMPSIZE "dumpsize"
107 * The spa_namespace_lock protects the zfsdev_state structure from being
108 * modified while it's being used, e.g. an open that comes in before a
109 * create finishes. It also protects temporary opens of the dataset so that,
110 * e.g., an open doesn't get a spurious EBUSY.
112 static uint32_t zvol_minors;
114 typedef struct zvol_extent {
116 dva_t ze_dva; /* dva associated with this extent */
117 uint64_t ze_nblks; /* number of blocks in extent */
121 * The in-core state of each volume.
123 typedef struct zvol_state {
124 char zv_name[MAXPATHLEN]; /* pool/dd name */
125 uint64_t zv_volsize; /* amount of space we advertise */
126 uint64_t zv_volblocksize; /* volume block size */
127 struct g_provider *zv_provider; /* GEOM provider */
128 uint8_t zv_min_bs; /* minimum addressable block shift */
129 uint8_t zv_flags; /* readonly, dumpified, etc. */
130 objset_t *zv_objset; /* objset handle */
131 uint32_t zv_total_opens; /* total open count */
132 zilog_t *zv_zilog; /* ZIL handle */
133 list_t zv_extents; /* List of extents for dump */
134 znode_t zv_znode; /* for range locking */
135 dmu_buf_t *zv_dbuf; /* bonus handle */
137 struct bio_queue_head zv_queue;
138 struct mtx zv_queue_mtx; /* zv_queue mutex */
142 * zvol specific flags
144 #define ZVOL_RDONLY 0x1
145 #define ZVOL_DUMPIFIED 0x2
146 #define ZVOL_EXCL 0x4
150 * zvol maximum transfer in one DMU tx.
152 int zvol_maxphys = DMU_MAX_ACCESS/2;
154 extern int zfs_set_prop_nvlist(const char *, zprop_source_t,
155 nvlist_t *, nvlist_t *);
156 static int zvol_remove_zv(zvol_state_t *);
157 static int zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio);
158 static int zvol_dumpify(zvol_state_t *zv);
159 static int zvol_dump_fini(zvol_state_t *zv);
160 static int zvol_dump_init(zvol_state_t *zv, boolean_t resize);
162 static zvol_state_t *zvol_geom_create(const char *name);
163 static void zvol_geom_run(zvol_state_t *zv);
164 static void zvol_geom_destroy(zvol_state_t *zv);
165 static int zvol_geom_access(struct g_provider *pp, int acr, int acw, int ace);
166 static void zvol_geom_start(struct bio *bp);
167 static void zvol_geom_worker(void *arg);
170 zvol_size_changed(zvol_state_t *zv)
173 dev_t dev = makedevice(maj, min);
175 VERIFY(ddi_prop_update_int64(dev, zfs_dip,
176 "Size", volsize) == DDI_SUCCESS);
177 VERIFY(ddi_prop_update_int64(dev, zfs_dip,
178 "Nblocks", lbtodb(volsize)) == DDI_SUCCESS);
180 /* Notify specfs to invalidate the cached size */
181 spec_size_invalidate(dev, VBLK);
182 spec_size_invalidate(dev, VCHR);
184 struct g_provider *pp;
186 pp = zv->zv_provider;
190 g_resize_provider(pp, zv->zv_volsize);
196 zvol_check_volsize(uint64_t volsize, uint64_t blocksize)
199 return (SET_ERROR(EINVAL));
201 if (volsize % blocksize != 0)
202 return (SET_ERROR(EINVAL));
205 if (volsize - 1 > SPEC_MAXOFFSET_T)
206 return (SET_ERROR(EOVERFLOW));
212 zvol_check_volblocksize(uint64_t volblocksize)
214 if (volblocksize < SPA_MINBLOCKSIZE ||
215 volblocksize > SPA_MAXBLOCKSIZE ||
217 return (SET_ERROR(EDOM));
223 zvol_get_stats(objset_t *os, nvlist_t *nv)
226 dmu_object_info_t doi;
229 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val);
233 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val);
235 error = dmu_object_info(os, ZVOL_OBJ, &doi);
238 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE,
239 doi.doi_data_block_size);
245 static zvol_state_t *
246 zvol_minor_lookup(const char *name)
248 struct g_provider *pp;
250 zvol_state_t *zv = NULL;
252 ASSERT(MUTEX_HELD(&spa_namespace_lock));
255 LIST_FOREACH(gp, &zfs_zvol_class.geom, geom) {
256 pp = LIST_FIRST(&gp->provider);
262 if (strcmp(zv->zv_name, name) == 0)
267 return (gp != NULL ? zv : NULL);
270 /* extent mapping arg */
278 zvol_map_block(spa_t *spa, zilog_t *zilog, const blkptr_t *bp,
279 const zbookmark_t *zb, const dnode_phys_t *dnp, void *arg)
281 struct maparg *ma = arg;
283 int bs = ma->ma_zv->zv_volblocksize;
285 if (BP_IS_HOLE(bp) ||
286 zb->zb_object != ZVOL_OBJ || zb->zb_level != 0)
289 VERIFY3U(ma->ma_blks, ==, zb->zb_blkid);
292 /* Abort immediately if we have encountered gang blocks */
294 return (SET_ERROR(EFRAGS));
297 * See if the block is at the end of the previous extent.
299 ze = list_tail(&ma->ma_zv->zv_extents);
301 DVA_GET_VDEV(BP_IDENTITY(bp)) == DVA_GET_VDEV(&ze->ze_dva) &&
302 DVA_GET_OFFSET(BP_IDENTITY(bp)) ==
303 DVA_GET_OFFSET(&ze->ze_dva) + ze->ze_nblks * bs) {
308 dprintf_bp(bp, "%s", "next blkptr:");
310 /* start a new extent */
311 ze = kmem_zalloc(sizeof (zvol_extent_t), KM_SLEEP);
312 ze->ze_dva = bp->blk_dva[0]; /* structure assignment */
314 list_insert_tail(&ma->ma_zv->zv_extents, ze);
319 zvol_free_extents(zvol_state_t *zv)
323 while (ze = list_head(&zv->zv_extents)) {
324 list_remove(&zv->zv_extents, ze);
325 kmem_free(ze, sizeof (zvol_extent_t));
330 zvol_get_lbas(zvol_state_t *zv)
332 objset_t *os = zv->zv_objset;
338 zvol_free_extents(zv);
340 /* commit any in-flight changes before traversing the dataset */
341 txg_wait_synced(dmu_objset_pool(os), 0);
342 err = traverse_dataset(dmu_objset_ds(os), 0,
343 TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA, zvol_map_block, &ma);
344 if (err || ma.ma_blks != (zv->zv_volsize / zv->zv_volblocksize)) {
345 zvol_free_extents(zv);
346 return (err ? err : EIO);
354 zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx)
356 zfs_creat_t *zct = arg;
357 nvlist_t *nvprops = zct->zct_props;
359 uint64_t volblocksize, volsize;
361 VERIFY(nvlist_lookup_uint64(nvprops,
362 zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0);
363 if (nvlist_lookup_uint64(nvprops,
364 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0)
365 volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE);
368 * These properties must be removed from the list so the generic
369 * property setting step won't apply to them.
371 VERIFY(nvlist_remove_all(nvprops,
372 zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0);
373 (void) nvlist_remove_all(nvprops,
374 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE));
376 error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize,
380 error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP,
384 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx);
389 * Replay a TX_WRITE ZIL transaction that didn't get committed
390 * after a system failure
393 zvol_replay_write(zvol_state_t *zv, lr_write_t *lr, boolean_t byteswap)
395 objset_t *os = zv->zv_objset;
396 char *data = (char *)(lr + 1); /* data follows lr_write_t */
397 uint64_t offset, length;
402 byteswap_uint64_array(lr, sizeof (*lr));
404 offset = lr->lr_offset;
405 length = lr->lr_length;
407 /* If it's a dmu_sync() block, write the whole block */
408 if (lr->lr_common.lrc_reclen == sizeof (lr_write_t)) {
409 uint64_t blocksize = BP_GET_LSIZE(&lr->lr_blkptr);
410 if (length < blocksize) {
411 offset -= offset % blocksize;
416 tx = dmu_tx_create(os);
417 dmu_tx_hold_write(tx, ZVOL_OBJ, offset, length);
418 error = dmu_tx_assign(tx, TXG_WAIT);
422 dmu_write(os, ZVOL_OBJ, offset, length, data, tx);
431 zvol_replay_err(zvol_state_t *zv, lr_t *lr, boolean_t byteswap)
433 return (SET_ERROR(ENOTSUP));
437 * Callback vectors for replaying records.
438 * Only TX_WRITE is needed for zvol.
440 zil_replay_func_t *zvol_replay_vector[TX_MAX_TYPE] = {
441 zvol_replay_err, /* 0 no such transaction type */
442 zvol_replay_err, /* TX_CREATE */
443 zvol_replay_err, /* TX_MKDIR */
444 zvol_replay_err, /* TX_MKXATTR */
445 zvol_replay_err, /* TX_SYMLINK */
446 zvol_replay_err, /* TX_REMOVE */
447 zvol_replay_err, /* TX_RMDIR */
448 zvol_replay_err, /* TX_LINK */
449 zvol_replay_err, /* TX_RENAME */
450 zvol_replay_write, /* TX_WRITE */
451 zvol_replay_err, /* TX_TRUNCATE */
452 zvol_replay_err, /* TX_SETATTR */
453 zvol_replay_err, /* TX_ACL */
454 zvol_replay_err, /* TX_CREATE_ACL */
455 zvol_replay_err, /* TX_CREATE_ATTR */
456 zvol_replay_err, /* TX_CREATE_ACL_ATTR */
457 zvol_replay_err, /* TX_MKDIR_ACL */
458 zvol_replay_err, /* TX_MKDIR_ATTR */
459 zvol_replay_err, /* TX_MKDIR_ACL_ATTR */
460 zvol_replay_err, /* TX_WRITE2 */
465 zvol_name2minor(const char *name, minor_t *minor)
469 mutex_enter(&spa_namespace_lock);
470 zv = zvol_minor_lookup(name);
472 *minor = zv->zv_minor;
473 mutex_exit(&spa_namespace_lock);
474 return (zv ? 0 : -1);
479 * Create a minor node (plus a whole lot more) for the specified volume.
482 zvol_create_minor(const char *name)
484 zfs_soft_state_t *zs;
487 dmu_object_info_t doi;
491 ZFS_LOG(1, "Creating ZVOL %s...", name);
493 mutex_enter(&spa_namespace_lock);
495 if (zvol_minor_lookup(name) != NULL) {
496 mutex_exit(&spa_namespace_lock);
497 return (SET_ERROR(EEXIST));
500 /* lie and say we're read-only */
501 error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, FTAG, &os);
504 mutex_exit(&spa_namespace_lock);
509 if ((minor = zfsdev_minor_alloc()) == 0) {
510 dmu_objset_disown(os, FTAG);
511 mutex_exit(&spa_namespace_lock);
512 return (SET_ERROR(ENXIO));
515 if (ddi_soft_state_zalloc(zfsdev_state, minor) != DDI_SUCCESS) {
516 dmu_objset_disown(os, FTAG);
517 mutex_exit(&spa_namespace_lock);
518 return (SET_ERROR(EAGAIN));
520 (void) ddi_prop_update_string(minor, zfs_dip, ZVOL_PROP_NAME,
523 (void) snprintf(chrbuf, sizeof (chrbuf), "%u,raw", minor);
525 if (ddi_create_minor_node(zfs_dip, chrbuf, S_IFCHR,
526 minor, DDI_PSEUDO, 0) == DDI_FAILURE) {
527 ddi_soft_state_free(zfsdev_state, minor);
528 dmu_objset_disown(os, FTAG);
529 mutex_exit(&spa_namespace_lock);
530 return (SET_ERROR(EAGAIN));
533 (void) snprintf(blkbuf, sizeof (blkbuf), "%u", minor);
535 if (ddi_create_minor_node(zfs_dip, blkbuf, S_IFBLK,
536 minor, DDI_PSEUDO, 0) == DDI_FAILURE) {
537 ddi_remove_minor_node(zfs_dip, chrbuf);
538 ddi_soft_state_free(zfsdev_state, minor);
539 dmu_objset_disown(os, FTAG);
540 mutex_exit(&spa_namespace_lock);
541 return (SET_ERROR(EAGAIN));
544 zs = ddi_get_soft_state(zfsdev_state, minor);
545 zs->zss_type = ZSST_ZVOL;
546 zv = zs->zss_data = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP);
549 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize);
552 dmu_objset_disown(os, zvol_tag);
553 mutex_exit(&spa_namespace_lock);
559 zv = zvol_geom_create(name);
560 zv->zv_volsize = volsize;
561 zv->zv_provider->mediasize = zv->zv_volsize;
565 (void) strlcpy(zv->zv_name, name, MAXPATHLEN);
566 zv->zv_min_bs = DEV_BSHIFT;
568 if (dmu_objset_is_snapshot(os) || !spa_writeable(dmu_objset_spa(os)))
569 zv->zv_flags |= ZVOL_RDONLY;
570 mutex_init(&zv->zv_znode.z_range_lock, NULL, MUTEX_DEFAULT, NULL);
571 avl_create(&zv->zv_znode.z_range_avl, zfs_range_compare,
572 sizeof (rl_t), offsetof(rl_t, r_node));
573 list_create(&zv->zv_extents, sizeof (zvol_extent_t),
574 offsetof(zvol_extent_t, ze_node));
575 /* get and cache the blocksize */
576 error = dmu_object_info(os, ZVOL_OBJ, &doi);
578 zv->zv_volblocksize = doi.doi_data_block_size;
580 if (spa_writeable(dmu_objset_spa(os))) {
581 if (zil_replay_disable)
582 zil_destroy(dmu_objset_zil(os), B_FALSE);
584 zil_replay(os, zv, zvol_replay_vector);
586 dmu_objset_disown(os, FTAG);
587 zv->zv_objset = NULL;
591 mutex_exit(&spa_namespace_lock);
598 ZFS_LOG(1, "ZVOL %s created.", name);
604 * Remove minor node for the specified volume.
607 zvol_remove_zv(zvol_state_t *zv)
610 minor_t minor = zv->zv_minor;
613 ASSERT(MUTEX_HELD(&spa_namespace_lock));
614 if (zv->zv_total_opens != 0)
615 return (SET_ERROR(EBUSY));
617 ZFS_LOG(1, "ZVOL %s destroyed.", zv->zv_name);
620 (void) snprintf(nmbuf, sizeof (nmbuf), "%u,raw", minor);
621 ddi_remove_minor_node(zfs_dip, nmbuf);
624 avl_destroy(&zv->zv_znode.z_range_avl);
625 mutex_destroy(&zv->zv_znode.z_range_lock);
627 zvol_geom_destroy(zv);
634 zvol_remove_minor(const char *name)
639 mutex_enter(&spa_namespace_lock);
640 if ((zv = zvol_minor_lookup(name)) == NULL) {
641 mutex_exit(&spa_namespace_lock);
642 return (SET_ERROR(ENXIO));
645 rc = zvol_remove_zv(zv);
647 mutex_exit(&spa_namespace_lock);
652 zvol_first_open(zvol_state_t *zv)
659 /* lie and say we're read-only */
660 error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, B_TRUE,
665 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize);
668 dmu_objset_disown(os, zvol_tag);
672 error = dmu_bonus_hold(os, ZVOL_OBJ, zvol_tag, &zv->zv_dbuf);
674 dmu_objset_disown(os, zvol_tag);
677 zv->zv_volsize = volsize;
678 zv->zv_zilog = zil_open(os, zvol_get_data);
679 zvol_size_changed(zv);
681 VERIFY(dsl_prop_get_integer(zv->zv_name, "readonly", &readonly,
683 if (readonly || dmu_objset_is_snapshot(os) ||
684 !spa_writeable(dmu_objset_spa(os)))
685 zv->zv_flags |= ZVOL_RDONLY;
687 zv->zv_flags &= ~ZVOL_RDONLY;
692 zvol_last_close(zvol_state_t *zv)
694 zil_close(zv->zv_zilog);
697 dmu_buf_rele(zv->zv_dbuf, zvol_tag);
703 if (dsl_dataset_is_dirty(dmu_objset_ds(zv->zv_objset)) &&
704 !(zv->zv_flags & ZVOL_RDONLY))
705 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
706 dmu_objset_evict_dbufs(zv->zv_objset);
708 dmu_objset_disown(zv->zv_objset, zvol_tag);
709 zv->zv_objset = NULL;
714 zvol_prealloc(zvol_state_t *zv)
716 objset_t *os = zv->zv_objset;
718 uint64_t refd, avail, usedobjs, availobjs;
719 uint64_t resid = zv->zv_volsize;
722 /* Check the space usage before attempting to allocate the space */
723 dmu_objset_space(os, &refd, &avail, &usedobjs, &availobjs);
724 if (avail < zv->zv_volsize)
725 return (SET_ERROR(ENOSPC));
727 /* Free old extents if they exist */
728 zvol_free_extents(zv);
732 uint64_t bytes = MIN(resid, SPA_MAXBLOCKSIZE);
734 tx = dmu_tx_create(os);
735 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes);
736 error = dmu_tx_assign(tx, TXG_WAIT);
739 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, off);
742 dmu_prealloc(os, ZVOL_OBJ, off, bytes, tx);
747 txg_wait_synced(dmu_objset_pool(os), 0);
754 zvol_update_volsize(objset_t *os, uint64_t volsize)
759 ASSERT(MUTEX_HELD(&spa_namespace_lock));
761 tx = dmu_tx_create(os);
762 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
763 error = dmu_tx_assign(tx, TXG_WAIT);
769 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1,
774 error = dmu_free_long_range(os,
775 ZVOL_OBJ, volsize, DMU_OBJECT_END);
780 zvol_remove_minors(const char *name)
782 struct g_geom *gp, *gptmp;
783 struct g_provider *pp;
787 namelen = strlen(name);
790 mutex_enter(&spa_namespace_lock);
793 LIST_FOREACH_SAFE(gp, &zfs_zvol_class.geom, geom, gptmp) {
794 pp = LIST_FIRST(&gp->provider);
800 if (strcmp(zv->zv_name, name) == 0 ||
801 (strncmp(zv->zv_name, name, namelen) == 0 &&
802 zv->zv_name[namelen] == '/')) {
803 (void) zvol_remove_zv(zv);
808 mutex_exit(&spa_namespace_lock);
813 zvol_set_volsize(const char *name, major_t maj, uint64_t volsize)
815 zvol_state_t *zv = NULL;
818 dmu_object_info_t doi;
819 uint64_t old_volsize = 0ULL;
822 mutex_enter(&spa_namespace_lock);
823 zv = zvol_minor_lookup(name);
824 if ((error = dmu_objset_hold(name, FTAG, &os)) != 0) {
825 mutex_exit(&spa_namespace_lock);
829 if ((error = dmu_object_info(os, ZVOL_OBJ, &doi)) != 0 ||
830 (error = zvol_check_volsize(volsize,
831 doi.doi_data_block_size)) != 0)
834 VERIFY(dsl_prop_get_integer(name, "readonly", &readonly,
841 error = zvol_update_volsize(os, volsize);
843 * Reinitialize the dump area to the new size. If we
844 * failed to resize the dump area then restore it back to
847 if (zv && error == 0) {
849 if (zv->zv_flags & ZVOL_DUMPIFIED) {
850 old_volsize = zv->zv_volsize;
851 zv->zv_volsize = volsize;
852 if ((error = zvol_dumpify(zv)) != 0 ||
853 (error = dumpvp_resize()) != 0) {
854 (void) zvol_update_volsize(os, old_volsize);
855 zv->zv_volsize = old_volsize;
856 error = zvol_dumpify(zv);
859 #endif /* ZVOL_DUMP */
861 zv->zv_volsize = volsize;
862 zvol_size_changed(zv);
868 * Generate a LUN expansion event.
870 if (zv && error == 0) {
873 char *physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
875 (void) snprintf(physpath, MAXPATHLEN, "%s%u", ZVOL_PSEUDO_DEV,
878 VERIFY(nvlist_alloc(&attr, NV_UNIQUE_NAME, KM_SLEEP) == 0);
879 VERIFY(nvlist_add_string(attr, DEV_PHYS_PATH, physpath) == 0);
881 (void) ddi_log_sysevent(zfs_dip, SUNW_VENDOR, EC_DEV_STATUS,
882 ESC_DEV_DLE, attr, &eid, DDI_SLEEP);
885 kmem_free(physpath, MAXPATHLEN);
890 dmu_objset_rele(os, FTAG);
892 mutex_exit(&spa_namespace_lock);
899 zvol_open(struct g_provider *pp, int flag, int count)
903 boolean_t locked = B_FALSE;
906 * Protect against recursively entering spa_namespace_lock
907 * when spa_open() is used for a pool on a (local) ZVOL(s).
908 * This is needed since we replaced upstream zfsdev_state_lock
909 * with spa_namespace_lock in the ZVOL code.
910 * We are using the same trick as spa_open().
911 * Note that calls in zvol_first_open which need to resolve
912 * pool name to a spa object will enter spa_open()
913 * recursively, but that function already has all the
914 * necessary protection.
916 if (!MUTEX_HELD(&spa_namespace_lock)) {
917 mutex_enter(&spa_namespace_lock);
924 mutex_exit(&spa_namespace_lock);
925 return (SET_ERROR(ENXIO));
928 if (zv->zv_total_opens == 0)
929 err = zvol_first_open(zv);
932 mutex_exit(&spa_namespace_lock);
935 if ((flag & FWRITE) && (zv->zv_flags & ZVOL_RDONLY)) {
936 err = SET_ERROR(EROFS);
939 if (zv->zv_flags & ZVOL_EXCL) {
940 err = SET_ERROR(EBUSY);
945 if (zv->zv_total_opens != 0) {
946 err = SET_ERROR(EBUSY);
949 zv->zv_flags |= ZVOL_EXCL;
953 zv->zv_total_opens += count;
955 mutex_exit(&spa_namespace_lock);
959 if (zv->zv_total_opens == 0)
962 mutex_exit(&spa_namespace_lock);
968 zvol_close(struct g_provider *pp, int flag, int count)
972 boolean_t locked = B_FALSE;
974 /* See comment in zvol_open(). */
975 if (!MUTEX_HELD(&spa_namespace_lock)) {
976 mutex_enter(&spa_namespace_lock);
983 mutex_exit(&spa_namespace_lock);
984 return (SET_ERROR(ENXIO));
987 if (zv->zv_flags & ZVOL_EXCL) {
988 ASSERT(zv->zv_total_opens == 1);
989 zv->zv_flags &= ~ZVOL_EXCL;
993 * If the open count is zero, this is a spurious close.
994 * That indicates a bug in the kernel / DDI framework.
996 ASSERT(zv->zv_total_opens != 0);
999 * You may get multiple opens, but only one close.
1001 zv->zv_total_opens -= count;
1003 if (zv->zv_total_opens == 0)
1004 zvol_last_close(zv);
1007 mutex_exit(&spa_namespace_lock);
1012 zvol_get_done(zgd_t *zgd, int error)
1015 dmu_buf_rele(zgd->zgd_db, zgd);
1017 zfs_range_unlock(zgd->zgd_rl);
1019 if (error == 0 && zgd->zgd_bp)
1020 zil_add_block(zgd->zgd_zilog, zgd->zgd_bp);
1022 kmem_free(zgd, sizeof (zgd_t));
1026 * Get data to generate a TX_WRITE intent log record.
1029 zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio)
1031 zvol_state_t *zv = arg;
1032 objset_t *os = zv->zv_objset;
1033 uint64_t object = ZVOL_OBJ;
1034 uint64_t offset = lr->lr_offset;
1035 uint64_t size = lr->lr_length; /* length of user data */
1036 blkptr_t *bp = &lr->lr_blkptr;
1041 ASSERT(zio != NULL);
1044 zgd = kmem_zalloc(sizeof (zgd_t), KM_SLEEP);
1045 zgd->zgd_zilog = zv->zv_zilog;
1046 zgd->zgd_rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER);
1049 * Write records come in two flavors: immediate and indirect.
1050 * For small writes it's cheaper to store the data with the
1051 * log record (immediate); for large writes it's cheaper to
1052 * sync the data and get a pointer to it (indirect) so that
1053 * we don't have to write the data twice.
1055 if (buf != NULL) { /* immediate write */
1056 error = dmu_read(os, object, offset, size, buf,
1057 DMU_READ_NO_PREFETCH);
1059 size = zv->zv_volblocksize;
1060 offset = P2ALIGN(offset, size);
1061 error = dmu_buf_hold(os, object, offset, zgd, &db,
1062 DMU_READ_NO_PREFETCH);
1064 blkptr_t *obp = dmu_buf_get_blkptr(db);
1066 ASSERT(BP_IS_HOLE(bp));
1073 ASSERT(db->db_offset == offset);
1074 ASSERT(db->db_size == size);
1076 error = dmu_sync(zio, lr->lr_common.lrc_txg,
1077 zvol_get_done, zgd);
1084 zvol_get_done(zgd, error);
1090 * zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions.
1092 * We store data in the log buffers if it's small enough.
1093 * Otherwise we will later flush the data out via dmu_sync().
1095 ssize_t zvol_immediate_write_sz = 32768;
1098 zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, offset_t off, ssize_t resid,
1101 uint32_t blocksize = zv->zv_volblocksize;
1102 zilog_t *zilog = zv->zv_zilog;
1104 ssize_t immediate_write_sz;
1106 if (zil_replaying(zilog, tx))
1109 immediate_write_sz = (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT)
1110 ? 0 : zvol_immediate_write_sz;
1112 slogging = spa_has_slogs(zilog->zl_spa) &&
1113 (zilog->zl_logbias == ZFS_LOGBIAS_LATENCY);
1119 itx_wr_state_t write_state;
1122 * Unlike zfs_log_write() we can be called with
1123 * upto DMU_MAX_ACCESS/2 (5MB) writes.
1125 if (blocksize > immediate_write_sz && !slogging &&
1126 resid >= blocksize && off % blocksize == 0) {
1127 write_state = WR_INDIRECT; /* uses dmu_sync */
1130 write_state = WR_COPIED;
1131 len = MIN(ZIL_MAX_LOG_DATA, resid);
1133 write_state = WR_NEED_COPY;
1134 len = MIN(ZIL_MAX_LOG_DATA, resid);
1137 itx = zil_itx_create(TX_WRITE, sizeof (*lr) +
1138 (write_state == WR_COPIED ? len : 0));
1139 lr = (lr_write_t *)&itx->itx_lr;
1140 if (write_state == WR_COPIED && dmu_read(zv->zv_objset,
1141 ZVOL_OBJ, off, len, lr + 1, DMU_READ_NO_PREFETCH) != 0) {
1142 zil_itx_destroy(itx);
1143 itx = zil_itx_create(TX_WRITE, sizeof (*lr));
1144 lr = (lr_write_t *)&itx->itx_lr;
1145 write_state = WR_NEED_COPY;
1148 itx->itx_wr_state = write_state;
1149 if (write_state == WR_NEED_COPY)
1150 itx->itx_sod += len;
1151 lr->lr_foid = ZVOL_OBJ;
1152 lr->lr_offset = off;
1153 lr->lr_length = len;
1155 BP_ZERO(&lr->lr_blkptr);
1157 itx->itx_private = zv;
1158 itx->itx_sync = sync;
1160 zil_itx_assign(zilog, itx, tx);
1169 zvol_dumpio_vdev(vdev_t *vd, void *addr, uint64_t offset, uint64_t origoffset,
1170 uint64_t size, boolean_t doread, boolean_t isdump)
1176 if (vd->vdev_ops == &vdev_mirror_ops ||
1177 vd->vdev_ops == &vdev_replacing_ops ||
1178 vd->vdev_ops == &vdev_spare_ops) {
1179 for (c = 0; c < vd->vdev_children; c++) {
1180 int err = zvol_dumpio_vdev(vd->vdev_child[c],
1181 addr, offset, origoffset, size, doread, isdump);
1184 } else if (doread) {
1190 if (!vd->vdev_ops->vdev_op_leaf && vd->vdev_ops != &vdev_raidz_ops)
1191 return (numerrors < vd->vdev_children ? 0 : EIO);
1193 if (doread && !vdev_readable(vd))
1194 return (SET_ERROR(EIO));
1195 else if (!doread && !vdev_writeable(vd))
1196 return (SET_ERROR(EIO));
1198 if (vd->vdev_ops == &vdev_raidz_ops) {
1199 return (vdev_raidz_physio(vd,
1200 addr, size, offset, origoffset, doread, isdump));
1203 offset += VDEV_LABEL_START_SIZE;
1205 if (ddi_in_panic() || isdump) {
1208 return (SET_ERROR(EIO));
1210 ASSERT3P(dvd, !=, NULL);
1211 return (ldi_dump(dvd->vd_lh, addr, lbtodb(offset),
1215 ASSERT3P(dvd, !=, NULL);
1216 return (vdev_disk_ldi_physio(dvd->vd_lh, addr, size,
1217 offset, doread ? B_READ : B_WRITE));
1222 zvol_dumpio(zvol_state_t *zv, void *addr, uint64_t offset, uint64_t size,
1223 boolean_t doread, boolean_t isdump)
1228 spa_t *spa = dmu_objset_spa(zv->zv_objset);
1230 /* Must be sector aligned, and not stradle a block boundary. */
1231 if (P2PHASE(offset, DEV_BSIZE) || P2PHASE(size, DEV_BSIZE) ||
1232 P2BOUNDARY(offset, size, zv->zv_volblocksize)) {
1233 return (SET_ERROR(EINVAL));
1235 ASSERT(size <= zv->zv_volblocksize);
1237 /* Locate the extent this belongs to */
1238 ze = list_head(&zv->zv_extents);
1239 while (offset >= ze->ze_nblks * zv->zv_volblocksize) {
1240 offset -= ze->ze_nblks * zv->zv_volblocksize;
1241 ze = list_next(&zv->zv_extents, ze);
1245 return (SET_ERROR(EINVAL));
1247 if (!ddi_in_panic())
1248 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
1250 vd = vdev_lookup_top(spa, DVA_GET_VDEV(&ze->ze_dva));
1251 offset += DVA_GET_OFFSET(&ze->ze_dva);
1252 error = zvol_dumpio_vdev(vd, addr, offset, DVA_GET_OFFSET(&ze->ze_dva),
1253 size, doread, isdump);
1255 if (!ddi_in_panic())
1256 spa_config_exit(spa, SCL_STATE, FTAG);
1263 zvol_strategy(struct bio *bp)
1265 zvol_state_t *zv = bp->bio_to->private;
1266 uint64_t off, volsize;
1272 boolean_t doread = (bp->bio_cmd == BIO_READ);
1273 boolean_t is_dumpified;
1277 g_io_deliver(bp, ENXIO);
1281 if (bp->bio_cmd != BIO_READ && (zv->zv_flags & ZVOL_RDONLY)) {
1282 g_io_deliver(bp, EROFS);
1286 off = bp->bio_offset;
1287 volsize = zv->zv_volsize;
1292 addr = bp->bio_data;
1293 resid = bp->bio_length;
1295 if (resid > 0 && (off < 0 || off >= volsize)) {
1296 g_io_deliver(bp, EIO);
1301 is_dumpified = zv->zv_flags & ZVOL_DUMPIFIED;
1303 is_dumpified = B_FALSE;
1305 sync = !doread && !is_dumpified &&
1306 zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS;
1309 * There must be no buffer changes when doing a dmu_sync() because
1310 * we can't change the data whilst calculating the checksum.
1312 rl = zfs_range_lock(&zv->zv_znode, off, resid,
1313 doread ? RL_READER : RL_WRITER);
1315 while (resid != 0 && off < volsize) {
1316 size_t size = MIN(resid, zvol_maxphys);
1319 size = MIN(size, P2END(off, zv->zv_volblocksize) - off);
1320 error = zvol_dumpio(zv, addr, off, size,
1322 } else if (doread) {
1326 error = dmu_read(os, ZVOL_OBJ, off, size, addr,
1329 dmu_tx_t *tx = dmu_tx_create(os);
1330 dmu_tx_hold_write(tx, ZVOL_OBJ, off, size);
1331 error = dmu_tx_assign(tx, TXG_WAIT);
1335 dmu_write(os, ZVOL_OBJ, off, size, addr, tx);
1336 zvol_log_write(zv, tx, off, size, sync);
1341 /* convert checksum errors into IO errors */
1342 if (error == ECKSUM)
1343 error = SET_ERROR(EIO);
1350 zfs_range_unlock(rl);
1352 bp->bio_completed = bp->bio_length - resid;
1353 if (bp->bio_completed < bp->bio_length)
1354 bp->bio_error = (off > volsize ? EINVAL : error);
1357 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1358 g_io_deliver(bp, 0);
1365 * Set the buffer count to the zvol maximum transfer.
1366 * Using our own routine instead of the default minphys()
1367 * means that for larger writes we write bigger buffers on X86
1368 * (128K instead of 56K) and flush the disk write cache less often
1369 * (every zvol_maxphys - currently 1MB) instead of minphys (currently
1370 * 56K on X86 and 128K on sparc).
1373 zvol_minphys(struct buf *bp)
1375 if (bp->b_bcount > zvol_maxphys)
1376 bp->b_bcount = zvol_maxphys;
1380 zvol_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblocks)
1382 minor_t minor = getminor(dev);
1389 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1391 return (SET_ERROR(ENXIO));
1393 if ((zv->zv_flags & ZVOL_DUMPIFIED) == 0)
1394 return (SET_ERROR(EINVAL));
1396 boff = ldbtob(blkno);
1397 resid = ldbtob(nblocks);
1399 VERIFY3U(boff + resid, <=, zv->zv_volsize);
1402 size = MIN(resid, P2END(boff, zv->zv_volblocksize) - boff);
1403 error = zvol_dumpio(zv, addr, boff, size, B_FALSE, B_TRUE);
1416 zvol_read(dev_t dev, uio_t *uio, cred_t *cr)
1418 minor_t minor = getminor(dev);
1424 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1426 return (SET_ERROR(ENXIO));
1428 volsize = zv->zv_volsize;
1429 if (uio->uio_resid > 0 &&
1430 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize))
1431 return (SET_ERROR(EIO));
1433 if (zv->zv_flags & ZVOL_DUMPIFIED) {
1434 error = physio(zvol_strategy, NULL, dev, B_READ,
1439 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid,
1441 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) {
1442 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1);
1444 /* don't read past the end */
1445 if (bytes > volsize - uio->uio_loffset)
1446 bytes = volsize - uio->uio_loffset;
1448 error = dmu_read_uio(zv->zv_objset, ZVOL_OBJ, uio, bytes);
1450 /* convert checksum errors into IO errors */
1451 if (error == ECKSUM)
1452 error = SET_ERROR(EIO);
1456 zfs_range_unlock(rl);
1462 zvol_write(dev_t dev, uio_t *uio, cred_t *cr)
1464 minor_t minor = getminor(dev);
1471 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1473 return (SET_ERROR(ENXIO));
1475 volsize = zv->zv_volsize;
1476 if (uio->uio_resid > 0 &&
1477 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize))
1478 return (SET_ERROR(EIO));
1480 if (zv->zv_flags & ZVOL_DUMPIFIED) {
1481 error = physio(zvol_strategy, NULL, dev, B_WRITE,
1486 sync = !(zv->zv_flags & ZVOL_WCE) ||
1487 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS);
1489 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid,
1491 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) {
1492 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1);
1493 uint64_t off = uio->uio_loffset;
1494 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset);
1496 if (bytes > volsize - off) /* don't write past the end */
1497 bytes = volsize - off;
1499 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes);
1500 error = dmu_tx_assign(tx, TXG_WAIT);
1505 error = dmu_write_uio_dbuf(zv->zv_dbuf, uio, bytes, tx);
1507 zvol_log_write(zv, tx, off, bytes, sync);
1513 zfs_range_unlock(rl);
1515 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1520 zvol_getefi(void *arg, int flag, uint64_t vs, uint8_t bs)
1522 struct uuid uuid = EFI_RESERVED;
1523 efi_gpe_t gpe = { 0 };
1529 if (ddi_copyin(arg, &efi, sizeof (dk_efi_t), flag))
1530 return (SET_ERROR(EFAULT));
1531 ptr = (char *)(uintptr_t)efi.dki_data_64;
1532 length = efi.dki_length;
1534 * Some clients may attempt to request a PMBR for the
1535 * zvol. Currently this interface will return EINVAL to
1536 * such requests. These requests could be supported by
1537 * adding a check for lba == 0 and consing up an appropriate
1540 if (efi.dki_lba < 1 || efi.dki_lba > 2 || length <= 0)
1541 return (SET_ERROR(EINVAL));
1543 gpe.efi_gpe_StartingLBA = LE_64(34ULL);
1544 gpe.efi_gpe_EndingLBA = LE_64((vs >> bs) - 1);
1545 UUID_LE_CONVERT(gpe.efi_gpe_PartitionTypeGUID, uuid);
1547 if (efi.dki_lba == 1) {
1548 efi_gpt_t gpt = { 0 };
1550 gpt.efi_gpt_Signature = LE_64(EFI_SIGNATURE);
1551 gpt.efi_gpt_Revision = LE_32(EFI_VERSION_CURRENT);
1552 gpt.efi_gpt_HeaderSize = LE_32(sizeof (gpt));
1553 gpt.efi_gpt_MyLBA = LE_64(1ULL);
1554 gpt.efi_gpt_FirstUsableLBA = LE_64(34ULL);
1555 gpt.efi_gpt_LastUsableLBA = LE_64((vs >> bs) - 1);
1556 gpt.efi_gpt_PartitionEntryLBA = LE_64(2ULL);
1557 gpt.efi_gpt_NumberOfPartitionEntries = LE_32(1);
1558 gpt.efi_gpt_SizeOfPartitionEntry =
1559 LE_32(sizeof (efi_gpe_t));
1560 CRC32(crc, &gpe, sizeof (gpe), -1U, crc32_table);
1561 gpt.efi_gpt_PartitionEntryArrayCRC32 = LE_32(~crc);
1562 CRC32(crc, &gpt, sizeof (gpt), -1U, crc32_table);
1563 gpt.efi_gpt_HeaderCRC32 = LE_32(~crc);
1564 if (ddi_copyout(&gpt, ptr, MIN(sizeof (gpt), length),
1566 return (SET_ERROR(EFAULT));
1567 ptr += sizeof (gpt);
1568 length -= sizeof (gpt);
1570 if (length > 0 && ddi_copyout(&gpe, ptr, MIN(sizeof (gpe),
1572 return (SET_ERROR(EFAULT));
1577 * BEGIN entry points to allow external callers access to the volume.
1580 * Return the volume parameters needed for access from an external caller.
1581 * These values are invariant as long as the volume is held open.
1584 zvol_get_volume_params(minor_t minor, uint64_t *blksize,
1585 uint64_t *max_xfer_len, void **minor_hdl, void **objset_hdl, void **zil_hdl,
1586 void **rl_hdl, void **bonus_hdl)
1590 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1592 return (SET_ERROR(ENXIO));
1593 if (zv->zv_flags & ZVOL_DUMPIFIED)
1594 return (SET_ERROR(ENXIO));
1596 ASSERT(blksize && max_xfer_len && minor_hdl &&
1597 objset_hdl && zil_hdl && rl_hdl && bonus_hdl);
1599 *blksize = zv->zv_volblocksize;
1600 *max_xfer_len = (uint64_t)zvol_maxphys;
1602 *objset_hdl = zv->zv_objset;
1603 *zil_hdl = zv->zv_zilog;
1604 *rl_hdl = &zv->zv_znode;
1605 *bonus_hdl = zv->zv_dbuf;
1610 * Return the current volume size to an external caller.
1611 * The size can change while the volume is open.
1614 zvol_get_volume_size(void *minor_hdl)
1616 zvol_state_t *zv = minor_hdl;
1618 return (zv->zv_volsize);
1622 * Return the current WCE setting to an external caller.
1623 * The WCE setting can change while the volume is open.
1626 zvol_get_volume_wce(void *minor_hdl)
1628 zvol_state_t *zv = minor_hdl;
1630 return ((zv->zv_flags & ZVOL_WCE) ? 1 : 0);
1634 * Entry point for external callers to zvol_log_write
1637 zvol_log_write_minor(void *minor_hdl, dmu_tx_t *tx, offset_t off, ssize_t resid,
1640 zvol_state_t *zv = minor_hdl;
1642 zvol_log_write(zv, tx, off, resid, sync);
1645 * END entry points to allow external callers access to the volume.
1649 * Dirtbag ioctls to support mkfs(1M) for UFS filesystems. See dkio(7I).
1653 zvol_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp)
1656 struct dk_cinfo dki;
1657 struct dk_minfo dkm;
1658 struct dk_callback *dkc;
1662 mutex_enter(&spa_namespace_lock);
1664 zv = zfsdev_get_soft_state(getminor(dev), ZSST_ZVOL);
1667 mutex_exit(&spa_namespace_lock);
1668 return (SET_ERROR(ENXIO));
1670 ASSERT(zv->zv_total_opens > 0);
1675 bzero(&dki, sizeof (dki));
1676 (void) strcpy(dki.dki_cname, "zvol");
1677 (void) strcpy(dki.dki_dname, "zvol");
1678 dki.dki_ctype = DKC_UNKNOWN;
1679 dki.dki_unit = getminor(dev);
1680 dki.dki_maxtransfer = 1 << (SPA_MAXBLOCKSHIFT - zv->zv_min_bs);
1681 mutex_exit(&spa_namespace_lock);
1682 if (ddi_copyout(&dki, (void *)arg, sizeof (dki), flag))
1683 error = SET_ERROR(EFAULT);
1686 case DKIOCGMEDIAINFO:
1687 bzero(&dkm, sizeof (dkm));
1688 dkm.dki_lbsize = 1U << zv->zv_min_bs;
1689 dkm.dki_capacity = zv->zv_volsize >> zv->zv_min_bs;
1690 dkm.dki_media_type = DK_UNKNOWN;
1691 mutex_exit(&spa_namespace_lock);
1692 if (ddi_copyout(&dkm, (void *)arg, sizeof (dkm), flag))
1693 error = SET_ERROR(EFAULT);
1698 uint64_t vs = zv->zv_volsize;
1699 uint8_t bs = zv->zv_min_bs;
1701 mutex_exit(&spa_namespace_lock);
1702 error = zvol_getefi((void *)arg, flag, vs, bs);
1706 case DKIOCFLUSHWRITECACHE:
1707 dkc = (struct dk_callback *)arg;
1708 mutex_exit(&spa_namespace_lock);
1709 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1710 if ((flag & FKIOCTL) && dkc != NULL && dkc->dkc_callback) {
1711 (*dkc->dkc_callback)(dkc->dkc_cookie, error);
1718 int wce = (zv->zv_flags & ZVOL_WCE) ? 1 : 0;
1719 if (ddi_copyout(&wce, (void *)arg, sizeof (int),
1721 error = SET_ERROR(EFAULT);
1727 if (ddi_copyin((void *)arg, &wce, sizeof (int),
1729 error = SET_ERROR(EFAULT);
1733 zv->zv_flags |= ZVOL_WCE;
1734 mutex_exit(&spa_namespace_lock);
1736 zv->zv_flags &= ~ZVOL_WCE;
1737 mutex_exit(&spa_namespace_lock);
1738 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1746 * commands using these (like prtvtoc) expect ENOTSUP
1747 * since we're emulating an EFI label
1749 error = SET_ERROR(ENOTSUP);
1753 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize,
1755 error = zvol_dumpify(zv);
1756 zfs_range_unlock(rl);
1760 if (!(zv->zv_flags & ZVOL_DUMPIFIED))
1762 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize,
1764 error = zvol_dump_fini(zv);
1765 zfs_range_unlock(rl);
1773 if (ddi_copyin((void *)arg, &df, sizeof (df), flag)) {
1774 error = SET_ERROR(EFAULT);
1779 * Apply Postel's Law to length-checking. If they overshoot,
1780 * just blank out until the end, if there's a need to blank
1783 if (df.df_start >= zv->zv_volsize)
1784 break; /* No need to do anything... */
1785 if (df.df_start + df.df_length > zv->zv_volsize)
1786 df.df_length = DMU_OBJECT_END;
1788 rl = zfs_range_lock(&zv->zv_znode, df.df_start, df.df_length,
1790 tx = dmu_tx_create(zv->zv_objset);
1791 error = dmu_tx_assign(tx, TXG_WAIT);
1795 zvol_log_truncate(zv, tx, df.df_start,
1796 df.df_length, B_TRUE);
1798 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ,
1799 df.df_start, df.df_length);
1802 zfs_range_unlock(rl);
1806 * If the write-cache is disabled or 'sync' property
1807 * is set to 'always' then treat this as a synchronous
1808 * operation (i.e. commit to zil).
1810 if (!(zv->zv_flags & ZVOL_WCE) ||
1811 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS))
1812 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1815 * If the caller really wants synchronous writes, and
1816 * can't wait for them, don't return until the write
1819 if (df.df_flags & DF_WAIT_SYNC) {
1821 dmu_objset_pool(zv->zv_objset), 0);
1828 error = SET_ERROR(ENOTTY);
1832 mutex_exit(&spa_namespace_lock);
1840 return (zvol_minors != 0);
1846 VERIFY(ddi_soft_state_init(&zfsdev_state, sizeof (zfs_soft_state_t),
1848 ZFS_LOG(1, "ZVOL Initialized.");
1854 ddi_soft_state_fini(&zfsdev_state);
1855 ZFS_LOG(1, "ZVOL Deinitialized.");
1861 zfs_mvdev_dump_feature_check(void *arg, dmu_tx_t *tx)
1863 spa_t *spa = dmu_tx_pool(tx)->dp_spa;
1865 if (spa_feature_is_active(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP))
1872 zfs_mvdev_dump_activate_feature_sync(void *arg, dmu_tx_t *tx)
1874 spa_t *spa = dmu_tx_pool(tx)->dp_spa;
1876 spa_feature_incr(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP, tx);
1880 zvol_dump_init(zvol_state_t *zv, boolean_t resize)
1884 objset_t *os = zv->zv_objset;
1885 spa_t *spa = dmu_objset_spa(os);
1886 vdev_t *vd = spa->spa_root_vdev;
1887 nvlist_t *nv = NULL;
1888 uint64_t version = spa_version(spa);
1889 enum zio_checksum checksum;
1891 ASSERT(MUTEX_HELD(&spa_namespace_lock));
1892 ASSERT(vd->vdev_ops == &vdev_root_ops);
1894 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 0,
1896 /* wait for dmu_free_long_range to actually free the blocks */
1897 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
1900 * If the pool on which the dump device is being initialized has more
1901 * than one child vdev, check that the MULTI_VDEV_CRASH_DUMP feature is
1902 * enabled. If so, bump that feature's counter to indicate that the
1903 * feature is active. We also check the vdev type to handle the
1905 * # zpool create test raidz disk1 disk2 disk3
1906 * Now have spa_root_vdev->vdev_children == 1 (the raidz vdev),
1907 * the raidz vdev itself has 3 children.
1909 if (vd->vdev_children > 1 || vd->vdev_ops == &vdev_raidz_ops) {
1910 if (!spa_feature_is_enabled(spa,
1911 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP))
1912 return (SET_ERROR(ENOTSUP));
1913 (void) dsl_sync_task(spa_name(spa),
1914 zfs_mvdev_dump_feature_check,
1915 zfs_mvdev_dump_activate_feature_sync, NULL, 2);
1918 tx = dmu_tx_create(os);
1919 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
1920 dmu_tx_hold_bonus(tx, ZVOL_OBJ);
1921 error = dmu_tx_assign(tx, TXG_WAIT);
1928 * If MULTI_VDEV_CRASH_DUMP is active, use the NOPARITY checksum
1929 * function. Otherwise, use the old default -- OFF.
1931 checksum = spa_feature_is_active(spa,
1932 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP) ? ZIO_CHECKSUM_NOPARITY :
1936 * If we are resizing the dump device then we only need to
1937 * update the refreservation to match the newly updated
1938 * zvolsize. Otherwise, we save off the original state of the
1939 * zvol so that we can restore them if the zvol is ever undumpified.
1942 error = zap_update(os, ZVOL_ZAP_OBJ,
1943 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1,
1944 &zv->zv_volsize, tx);
1946 uint64_t checksum, compress, refresrv, vbs, dedup;
1948 error = dsl_prop_get_integer(zv->zv_name,
1949 zfs_prop_to_name(ZFS_PROP_COMPRESSION), &compress, NULL);
1950 error = error ? error : dsl_prop_get_integer(zv->zv_name,
1951 zfs_prop_to_name(ZFS_PROP_CHECKSUM), &checksum, NULL);
1952 error = error ? error : dsl_prop_get_integer(zv->zv_name,
1953 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &refresrv, NULL);
1954 error = error ? error : dsl_prop_get_integer(zv->zv_name,
1955 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &vbs, NULL);
1956 if (version >= SPA_VERSION_DEDUP) {
1957 error = error ? error :
1958 dsl_prop_get_integer(zv->zv_name,
1959 zfs_prop_to_name(ZFS_PROP_DEDUP), &dedup, NULL);
1962 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1963 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1,
1965 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1966 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum, tx);
1967 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1968 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1,
1970 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1971 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1,
1973 error = error ? error : dmu_object_set_blocksize(
1974 os, ZVOL_OBJ, SPA_MAXBLOCKSIZE, 0, tx);
1975 if (version >= SPA_VERSION_DEDUP) {
1976 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1977 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1,
1981 zv->zv_volblocksize = SPA_MAXBLOCKSIZE;
1986 * We only need update the zvol's property if we are initializing
1987 * the dump area for the first time.
1990 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1991 VERIFY(nvlist_add_uint64(nv,
1992 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 0) == 0);
1993 VERIFY(nvlist_add_uint64(nv,
1994 zfs_prop_to_name(ZFS_PROP_COMPRESSION),
1995 ZIO_COMPRESS_OFF) == 0);
1996 VERIFY(nvlist_add_uint64(nv,
1997 zfs_prop_to_name(ZFS_PROP_CHECKSUM),
1999 if (version >= SPA_VERSION_DEDUP) {
2000 VERIFY(nvlist_add_uint64(nv,
2001 zfs_prop_to_name(ZFS_PROP_DEDUP),
2002 ZIO_CHECKSUM_OFF) == 0);
2005 error = zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL,
2013 /* Allocate the space for the dump */
2014 error = zvol_prealloc(zv);
2019 zvol_dumpify(zvol_state_t *zv)
2022 uint64_t dumpsize = 0;
2024 objset_t *os = zv->zv_objset;
2026 if (zv->zv_flags & ZVOL_RDONLY)
2027 return (SET_ERROR(EROFS));
2029 if (zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE,
2030 8, 1, &dumpsize) != 0 || dumpsize != zv->zv_volsize) {
2031 boolean_t resize = (dumpsize > 0);
2033 if ((error = zvol_dump_init(zv, resize)) != 0) {
2034 (void) zvol_dump_fini(zv);
2040 * Build up our lba mapping.
2042 error = zvol_get_lbas(zv);
2044 (void) zvol_dump_fini(zv);
2048 tx = dmu_tx_create(os);
2049 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
2050 error = dmu_tx_assign(tx, TXG_WAIT);
2053 (void) zvol_dump_fini(zv);
2057 zv->zv_flags |= ZVOL_DUMPIFIED;
2058 error = zap_update(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 8, 1,
2059 &zv->zv_volsize, tx);
2063 (void) zvol_dump_fini(zv);
2067 txg_wait_synced(dmu_objset_pool(os), 0);
2072 zvol_dump_fini(zvol_state_t *zv)
2075 objset_t *os = zv->zv_objset;
2078 uint64_t checksum, compress, refresrv, vbs, dedup;
2079 uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset));
2082 * Attempt to restore the zvol back to its pre-dumpified state.
2083 * This is a best-effort attempt as it's possible that not all
2084 * of these properties were initialized during the dumpify process
2085 * (i.e. error during zvol_dump_init).
2088 tx = dmu_tx_create(os);
2089 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
2090 error = dmu_tx_assign(tx, TXG_WAIT);
2095 (void) zap_remove(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, tx);
2098 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
2099 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum);
2100 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
2101 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, &compress);
2102 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
2103 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, &refresrv);
2104 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
2105 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, &vbs);
2107 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0);
2108 (void) nvlist_add_uint64(nv,
2109 zfs_prop_to_name(ZFS_PROP_CHECKSUM), checksum);
2110 (void) nvlist_add_uint64(nv,
2111 zfs_prop_to_name(ZFS_PROP_COMPRESSION), compress);
2112 (void) nvlist_add_uint64(nv,
2113 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), refresrv);
2114 if (version >= SPA_VERSION_DEDUP &&
2115 zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
2116 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, &dedup) == 0) {
2117 (void) nvlist_add_uint64(nv,
2118 zfs_prop_to_name(ZFS_PROP_DEDUP), dedup);
2120 (void) zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL,
2124 zvol_free_extents(zv);
2125 zv->zv_flags &= ~ZVOL_DUMPIFIED;
2126 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, DMU_OBJECT_END);
2127 /* wait for dmu_free_long_range to actually free the blocks */
2128 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
2129 tx = dmu_tx_create(os);
2130 dmu_tx_hold_bonus(tx, ZVOL_OBJ);
2131 error = dmu_tx_assign(tx, TXG_WAIT);
2136 if (dmu_object_set_blocksize(os, ZVOL_OBJ, vbs, 0, tx) == 0)
2137 zv->zv_volblocksize = vbs;
2144 static zvol_state_t *
2145 zvol_geom_create(const char *name)
2147 struct g_provider *pp;
2151 gp = g_new_geomf(&zfs_zvol_class, "zfs::zvol::%s", name);
2152 gp->start = zvol_geom_start;
2153 gp->access = zvol_geom_access;
2154 pp = g_new_providerf(gp, "%s/%s", ZVOL_DRIVER, name);
2155 pp->flags |= G_PF_DIRECT_RECEIVE | G_PF_DIRECT_SEND;
2156 pp->sectorsize = DEV_BSIZE;
2158 zv = kmem_zalloc(sizeof(*zv), KM_SLEEP);
2159 zv->zv_provider = pp;
2161 bioq_init(&zv->zv_queue);
2162 mtx_init(&zv->zv_queue_mtx, "zvol", NULL, MTX_DEF);
2170 zvol_geom_run(zvol_state_t *zv)
2172 struct g_provider *pp;
2174 pp = zv->zv_provider;
2175 g_error_provider(pp, 0);
2177 kproc_kthread_add(zvol_geom_worker, zv, &zfsproc, NULL, 0, 0,
2178 "zfskern", "zvol %s", pp->name + sizeof(ZVOL_DRIVER));
2182 zvol_geom_destroy(zvol_state_t *zv)
2184 struct g_provider *pp;
2186 g_topology_assert();
2188 mtx_lock(&zv->zv_queue_mtx);
2190 wakeup_one(&zv->zv_queue);
2191 while (zv->zv_state != 2)
2192 msleep(&zv->zv_state, &zv->zv_queue_mtx, 0, "zvol:w", 0);
2193 mtx_destroy(&zv->zv_queue_mtx);
2195 pp = zv->zv_provider;
2196 zv->zv_provider = NULL;
2198 g_wither_geom(pp->geom, ENXIO);
2200 kmem_free(zv, sizeof(*zv));
2204 zvol_geom_access(struct g_provider *pp, int acr, int acw, int ace)
2206 int count, error, flags;
2208 g_topology_assert();
2211 * To make it easier we expect either open or close, but not both
2214 KASSERT((acr >= 0 && acw >= 0 && ace >= 0) ||
2215 (acr <= 0 && acw <= 0 && ace <= 0),
2216 ("Unsupported access request to %s (acr=%d, acw=%d, ace=%d).",
2217 pp->name, acr, acw, ace));
2219 if (pp->private == NULL) {
2220 if (acr <= 0 && acw <= 0 && ace <= 0)
2226 * We don't pass FEXCL flag to zvol_open()/zvol_close() if ace != 0,
2227 * because GEOM already handles that and handles it a bit differently.
2228 * GEOM allows for multiple read/exclusive consumers and ZFS allows
2229 * only one exclusive consumer, no matter if it is reader or writer.
2230 * I like better the way GEOM works so I'll leave it for GEOM to
2231 * decide what to do.
2234 count = acr + acw + ace;
2239 if (acr != 0 || ace != 0)
2244 g_topology_unlock();
2246 error = zvol_open(pp, flags, count);
2248 error = zvol_close(pp, flags, -count);
2254 zvol_geom_start(struct bio *bp)
2259 zv = bp->bio_to->private;
2261 switch (bp->bio_cmd) {
2263 if (!THREAD_CAN_SLEEP())
2265 zil_commit(zv->zv_zilog, ZVOL_OBJ);
2266 g_io_deliver(bp, 0);
2270 if (!THREAD_CAN_SLEEP())
2277 g_io_deliver(bp, EOPNOTSUPP);
2283 mtx_lock(&zv->zv_queue_mtx);
2284 first = (bioq_first(&zv->zv_queue) == NULL);
2285 bioq_insert_tail(&zv->zv_queue, bp);
2286 mtx_unlock(&zv->zv_queue_mtx);
2288 wakeup_one(&zv->zv_queue);
2292 zvol_geom_worker(void *arg)
2297 thread_lock(curthread);
2298 sched_prio(curthread, PRIBIO);
2299 thread_unlock(curthread);
2303 mtx_lock(&zv->zv_queue_mtx);
2304 bp = bioq_takefirst(&zv->zv_queue);
2306 if (zv->zv_state == 1) {
2308 wakeup(&zv->zv_state);
2309 mtx_unlock(&zv->zv_queue_mtx);
2312 msleep(&zv->zv_queue, &zv->zv_queue_mtx, PRIBIO | PDROP,
2316 mtx_unlock(&zv->zv_queue_mtx);
2317 switch (bp->bio_cmd) {
2319 zil_commit(zv->zv_zilog, ZVOL_OBJ);
2320 g_io_deliver(bp, 0);
2330 extern boolean_t dataset_name_hidden(const char *name);
2333 zvol_create_snapshots(objset_t *os, const char *name)
2335 uint64_t cookie, obj;
2340 sname = kmem_alloc(MAXPATHLEN, KM_SLEEP);
2343 (void) dmu_objset_find(name, dmu_objset_prefetch, NULL,
2348 len = snprintf(sname, MAXPATHLEN, "%s@", name);
2349 if (len >= MAXPATHLEN) {
2350 dmu_objset_rele(os, FTAG);
2351 error = ENAMETOOLONG;
2355 dsl_pool_config_enter(dmu_objset_pool(os), FTAG);
2356 error = dmu_snapshot_list_next(os, MAXPATHLEN - len,
2357 sname + len, &obj, &cookie, NULL);
2358 dsl_pool_config_exit(dmu_objset_pool(os), FTAG);
2360 if (error == ENOENT)
2365 if ((error = zvol_create_minor(sname)) != 0) {
2366 printf("ZFS WARNING: Unable to create ZVOL %s (error=%d).\n",
2372 kmem_free(sname, MAXPATHLEN);
2377 zvol_create_minors(const char *name)
2384 if (dataset_name_hidden(name))
2387 if ((error = dmu_objset_hold(name, FTAG, &os)) != 0) {
2388 printf("ZFS WARNING: Unable to put hold on %s (error=%d).\n",
2392 if (dmu_objset_type(os) == DMU_OST_ZVOL) {
2393 dsl_dataset_long_hold(os->os_dsl_dataset, FTAG);
2394 dsl_pool_rele(dmu_objset_pool(os), FTAG);
2395 if ((error = zvol_create_minor(name)) == 0)
2396 error = zvol_create_snapshots(os, name);
2398 printf("ZFS WARNING: Unable to create ZVOL %s (error=%d).\n",
2401 dsl_dataset_long_rele(os->os_dsl_dataset, FTAG);
2402 dsl_dataset_rele(os->os_dsl_dataset, FTAG);
2405 if (dmu_objset_type(os) != DMU_OST_ZFS) {
2406 dmu_objset_rele(os, FTAG);
2410 osname = kmem_alloc(MAXPATHLEN, KM_SLEEP);
2411 if (snprintf(osname, MAXPATHLEN, "%s/", name) >= MAXPATHLEN) {
2412 dmu_objset_rele(os, FTAG);
2413 kmem_free(osname, MAXPATHLEN);
2416 p = osname + strlen(osname);
2417 len = MAXPATHLEN - (p - osname);
2420 /* Prefetch the datasets. */
2422 while (dmu_dir_list_next(os, len, p, NULL, &cookie) == 0) {
2423 if (!dataset_name_hidden(osname))
2424 (void) dmu_objset_prefetch(osname, NULL);
2429 while (dmu_dir_list_next(os, MAXPATHLEN - (p - osname), p, NULL,
2431 dmu_objset_rele(os, FTAG);
2432 (void)zvol_create_minors(osname);
2433 if ((error = dmu_objset_hold(name, FTAG, &os)) != 0) {
2434 printf("ZFS WARNING: Unable to put hold on %s (error=%d).\n",
2440 dmu_objset_rele(os, FTAG);
2441 kmem_free(osname, MAXPATHLEN);
2446 zvol_rename_minor(struct g_geom *gp, const char *newname)
2448 struct g_provider *pp;
2451 ASSERT(MUTEX_HELD(&spa_namespace_lock));
2452 g_topology_assert();
2454 pp = LIST_FIRST(&gp->provider);
2459 zv->zv_provider = NULL;
2460 g_wither_provider(pp, ENXIO);
2462 pp = g_new_providerf(gp, "%s/%s", ZVOL_DRIVER, newname);
2463 pp->flags |= G_PF_DIRECT_RECEIVE | G_PF_DIRECT_SEND;
2464 pp->sectorsize = DEV_BSIZE;
2465 pp->mediasize = zv->zv_volsize;
2467 zv->zv_provider = pp;
2468 strlcpy(zv->zv_name, newname, sizeof(zv->zv_name));
2469 g_error_provider(pp, 0);
2473 zvol_rename_minors(const char *oldname, const char *newname)
2475 char name[MAXPATHLEN];
2476 struct g_provider *pp;
2478 size_t oldnamelen, newnamelen;
2482 oldnamelen = strlen(oldname);
2483 newnamelen = strlen(newname);
2486 mutex_enter(&spa_namespace_lock);
2489 LIST_FOREACH(gp, &zfs_zvol_class.geom, geom) {
2490 pp = LIST_FIRST(&gp->provider);
2496 if (strcmp(zv->zv_name, oldname) == 0) {
2497 zvol_rename_minor(gp, newname);
2498 } else if (strncmp(zv->zv_name, oldname, oldnamelen) == 0 &&
2499 (zv->zv_name[oldnamelen] == '/' ||
2500 zv->zv_name[oldnamelen] == '@')) {
2501 snprintf(name, sizeof(name), "%s%c%s", newname,
2502 zv->zv_name[oldnamelen],
2503 zv->zv_name + oldnamelen + 1);
2504 zvol_rename_minor(gp, name);
2508 g_topology_unlock();
2509 mutex_exit(&spa_namespace_lock);