Merge ZFS version 15 and almost all OpenSolaris bugfixes referenced

in Solaris 10 updates 141445-09 and 142901-14.

Detailed information:
(OpenSolaris revisions and Bug IDs, Solaris 10 patch numbers)

7844:effed23820ae
6755435	zfs_open() and zfs_close() needs to use ZFS_ENTER/ZFS_VERIFY_ZP (141445-01)

7897:e520d8258820
6748436	inconsistent zpool.cache in boot_archive could panic a zfs root filesystem upon boot-up (141445-01)

7965:b795da521357
6740164	zpool attach can create an illegal root pool (141909-02)

8084:b811cc60d650
6769612	zpool_import() will continue to write to cachefile even if altroot is set (N/A)

8121:7fd09d4ebd9c
6757430	want an option for zdb to disable space map loading and leak tracking (141445-01)

8129:e4f45a0bfbb0
6542860	ASSERT: reason != VDEV_LABEL_REMOVE||vdev_inuse(vd, crtxg, reason, 0) (141445-01)

8188:fd00c0a81e80
6761100	want zdb option to select older uberblocks (141445-01)

8190:6eeea43ced42
6774886	zfs_setattr() won't allow ndmp to restore SUNWattr_rw (141445-01)

8225:59a9961c2aeb
6737463	panic while trying to write out config file if root pool import fails (141445-01)

8227:f7d7be9b1f56
6765294	Refactor replay (141445-01)

8228:51e9ca9ee3a5
6572357	libzfs should do more to avoid mnttab lookups (141909-01)
6572376	zfs_iter_filesystems and zfs_iter_snapshots get objset stats twice (141909-01)

8241:5a60f16123ba
6328632	zpool offline is a bit too conservative (141445-01)
6739487	ASSERT: txg <= spa_final_txg due to scrub/export race (141445-01)
6767129	ASSERT: cvd->vdev_isspare, in spa_vdev_detach() (141445-01)
6747698	checksum failures after offline -t / export / import / scrub (141445-01)
6745863	ZFS writes to disk after it has been offlined (141445-01)
6722540	50% slowdown on scrub/resilver with certain vdev configurations (141445-01)
6759999	resilver logic rewrites ditto blocks on both source and destination (141445-01)
6758107	I/O should never suspend during spa_load() (141445-01)
6776548	codereview(1) runs off the page when faced with multi-line comments (N/A)
6761406	AMD errata 91 workaround doesn't work on 64-bit systems (141445-01)

8242:e46e4b2f0a03
6770866	GRUB/ZFS should require physical path or devid, but not both (141445-01)

8269:03a7e9050cfd
6674216	"zfs share" doesn't work, but "zfs set sharenfs=on" does (141445-01)
6621164	$SRC/cmd/zfs/zfs_main.c seems to have a syntax error in the translation note (141445-01)
6635482	i18n problems in libzfs_dataset.c and zfs_main.c (141445-01)
6595194	"zfs get" VALUE column is as wide as NAME (141445-01)
6722991	vdev_disk.c: error checking for ddi_pathname_to_dev_t() must test for NODEV (141445-01)
6396518	ASSERT strings shouldn't be pre-processed (141445-01)

8274:846b39508aff
6713916	scrub/resilver needlessly decompress data (141445-01)

8343:655db2375fed
6739553	libzfs_status msgid table is out of sync (141445-01)
6784104	libzfs unfairly rejects numerical values greater than 2^63 (141445-01)
6784108	zfs_realloc() should not free original memory on failure (141445-01)

8525:e0e0e525d0f8
6788830	set large value to reservation cause core dump (141445-01)
6791064	want sysevents for ZFS scrub (141445-01)
6791066	need to be able to set cachefile on faulted pools (141445-01)
6791071	zpool_do_import() should not enable datasets on faulted pools (141445-01)
6792134	getting multiple properties on a faulted pool leads to confusion (141445-01)

8547:bcc7b46e5ff7
6792884	Vista clients cannot access .zfs (141445-01)

8632:36ef517870a3
6798384	It can take a village to raise a zio (141445-01)

8636:7e4ce9158df3
6551866	deadlock between zfs_write(), zfs_freesp(), and zfs_putapage() (141909-01)
6504953	zfs_getpage() misunderstands VOP_GETPAGE() interface (141909-01)
6702206	ZFS read/writer lock contention throttles sendfile() benchmark (141445-01)
6780491	Zone on a ZFS filesystem has poor fork/exec performance (141445-01)
6747596	assertion failed: DVA_EQUAL(BP_IDENTITY(&zio->io_bp_orig), BP_IDENTITY(zio->io_bp))); (141445-01)

8692:692d4668b40d
6801507	ZFS read aggregation should not mind the gap (141445-01)

8697:e62d2612c14d
6633095	creating a filesystem with many properties set is slow (141445-01)

8768:dfecfdbb27ed
6775697	oracle crashes when overwriting after hitting quota on zfs (141909-01)

8811:f8deccf701cf
6790687	libzfs mnttab caching ignores external changes (141445-01)
6791101	memory leak from libzfs_mnttab_init (141445-01)

8845:91af0d9c0790
6800942	smb_session_create() incorrectly stores IP addresses (N/A)
6582163	Access Control List (ACL) for shares (141445-01)
6804954	smb_search - shortname field should be space padded following the NULL terminator (N/A)
6800184	Panic at smb_oplock_conflict+0x35() (N/A)

8876:59d2e67b4b65
6803822	Reboot after replacement of system disk in a ZFS mirror drops to grub> prompt (141445-01)

8924:5af812f84759
6789318	coredump when issue zdb -uuuu poolname/ (141445-01)
6790345 zdb -dddd -e poolname coredump (141445-01)
6797109 zdb: 'zdb -dddddd pool_name/fs_name inode' coredump if the file with inode was deleted (141445-01)
6797118 zdb: 'zdb -dddddd poolname inum' coredump if I miss the fs name (141445-01)
6803343 shareiscsi=on failed, iscsitgtd failed request to share (141445-01)

9030:243fd360d81f
6815893	hang mounting a dataset after booting into a new boot environment (141445-01)

9056:826e1858a846
6809691	'zpool create -f' no longer overwrites ufs infomation (141445-01)

9179:d8fbd96b79b3
6790064	zfs needs to determine uid and gid earlier in create process (141445-01)

9214:8d350e5d04aa
6604992	forced unmount + being in .zfs/snapshot/<snap1> = not happy (141909-01)
6810367	assertion failed: dvp->v_flag & VROOT, file: ../../common/fs/gfs.c, line: 426 (141909-01)

9229:e3f8b41e5db4
6807765	ztest_dsl_dataset_promote_busy needs to clean up after ENOSPC (141445-01)

9230:e4561e3eb1ef
6821169	offlining a device results in checksum errors (141445-01)
6821170	ZFS should not increment error stats for unavailable devices (141445-01)
6824006	need to increase issue and interrupt taskqs threads in zfs (141445-01)

9234:bffdc4fc05c4
6792139	recovering from a suspended pool needs some work (141445-01)
6794830	reboot command hangs on a failed zfs pool (141445-01)

9246:67c03c93c071
6824062	System panicked in zfs_mount due to NULL pointer dereference when running btts and svvs tests (141909-01)

9276:a8a7fc849933
6816124	System crash running zpool destroy on broken zpool (141445-03)

9355:09928982c591
6818183	zfs snapshot -r is slow due to set_snap_props() doing txg_wait_synced() for each new snapshot (141445-03)

9391:413d0661ef33
6710376	log device can show incorrect status when other parts of pool are degraded (141445-03)

9396:f41cf682d0d3 (part already merged)
6501037	want user/group quotas on ZFS (141445-03)
6827260	assertion failed in arc_read(): hdr == pbuf->b_hdr (141445-03)
6815592	panic: No such hold X on refcount Y from zfs_znode_move (141445-03)
6759986	zfs list shows temporary %clone when doing online zfs recv (141445-03)

9404:319573cd93f8
6774713	zfs ignores canmount=noauto when sharenfs property != off (141445-03)

9412:4aefd8704ce0
6717022	ZFS DMU needs zero-copy support (141445-03)

9425:e7ffacaec3a8
6799895	spa_add_spares() needs to be protected by config lock (141445-03)
6826466	want to post sysevents on hot spare activation (141445-03)
6826468	spa 'allowfaulted' needs some work (141445-03)
6826469	kernel support for storing vdev FRU information (141445-03)
6826470	skip posting checksum errors from DTL regions of leaf vdevs (141445-03)
6826471	I/O errors after device remove probe can confuse FMA (141445-03)
6826472	spares should enjoy some of the benefits of cache devices (141445-03)

9443:2a96d8478e95
6833711	gang leaders shouldn't have to be logical (141445-03)

9463:d0bd231c7518
6764124	want zdb to be able to checksum metadata blocks only (141445-03)

9465:8372081b8019
6830237	zfs panic in zfs_groupmember() (141445-03)

9466:1fdfd1fed9c4
6833162	phantom log device in zpool status (141445-03)

9469:4f68f041ddcd
6824968	add ZFS userquota support to rquotad (141445-03)

9470:6d827468d7b5
6834217	godfather I/O should reexecute (141445-03)

9480:fcff33da767f
6596237	Stop looking and start ganging (141909-02)

9493:9933d599bc93
6623978	lwb->lwb_buf != NULL, file ../../../uts/common/fs/zfs/zil.c, line 787, function zil_lwb_commit (141445-06)

9512:64cafcbcc337
6801810	Commit of aligned streaming rewrites to ZIL device causes unwanted disk reads (N/A)

9515:d3b739d9d043
6586537	async zio taskqs can block out userland commands (142901-09)

9554:787363635b6a
6836768	zfs_userspace() callback has no way to indicate failure (N/A)

9574:1eb6a6ab2c57
6838062	zfs panics when an error is encountered in space_map_load() (141909-02)

9583:b0696cd037cc
6794136	Panic BAD TRAP: type=e when importing degraded zraid pool. (141909-03)

9630:e25a03f552e0
6776104	"zfs import" deadlock between spa_unload() and spa_async_thread() (141445-06)

9653:a70048a304d1
6664765	Unable to remove files when using fat-zap and quota exceeded on ZFS filesystem (141445-06)

9688:127be1845343
6841321	zfs userspace / zfs get userused@ doesn't work on mounted snapshot (N/A)
6843069	zfs get userused@S-1-... doesn't work (N/A)

9873:8ddc892eca6e
6847229	assertion failed: refcount_count(&tx->tx_space_written) + delta <= tx->tx_space_towrite in dmu_tx.c (141445-06)

9904:d260bd3fd47c
6838344	kernel heap corruption detected on zil while stress testing (141445-06)

9951:a4895b3dd543
6844900	zfs_ioc_userspace_upgrade leaks (N/A)

10040:38b25aeeaf7a
6857012	zfs panics on zpool import (141445-06)

10000:241a51d8720c
6848242	zdb -e no longer works as expected (N/A)

10100:4a6965f6bef8
6856634	snv_117 not booting: zfs_parse_bootfs: error2 (141445-07)

10160:a45b03783d44
6861983	zfs should use new name <-> SID interfaces (N/A)
6862984	userquota commands can hang (141445-06)

10299:80845694147f
6696858	zfs receive of incremental replication stream can dereference NULL pointer and crash (N/A)

10302:a9e3d1987706
6696858	zfs receive of incremental replication stream can dereference NULL pointer and crash (fix lint) (N/A)

10575:2a8816c5173b (partial merge)
6882227 spa_async_remove() shouldn't do a full clear (142901-14)

10800:469478b180d9
6880764	fsync on zfs is broken if writes are greater than 32kb on a hard crash and no log attached (142901-09)
6793430 zdb -ivvvv assertion failure: bp->blk_cksum.zc_word[2] == dmu_objset_id(zilog->zl_os) (N/A)

10801:e0bf032e8673 (partial merge)
6822816 assertion failed: zap_remove_int(ds_next_clones_obj) returns ENOENT (142901-09)

10810:b6b161a6ae4a
6892298 buf->b_hdr->b_state != arc_anon, file: ../../common/fs/zfs/arc.c, line: 2849 (142901-09)

10890:499786962772
6807339	spurious checksum errors when replacing a vdev (142901-13)

11249:6c30f7dfc97b
6906110 bad trap panic in zil_replay_log_record (142901-13)
6906946 zfs replay isn't handling uid/gid correctly (142901-13)

11454:6e69bacc1a5a
6898245 suspended zpool should not cause rest of the zfs/zpool commands to hang (142901-10)

11546:42ea6be8961b (partial merge)
6833999 3-way deadlock in dsl_dataset_hold_ref() and dsl_sync_task_group_sync() (142901-09)

Discussed with:	pjd
Approved by:	delphij (mentor)
Obtained from:	OpenSolaris (multiple Bug IDs)
MFC after:	2 months

1 files changed, 220 insertions, 13 deletions

diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ctldir.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ctldir.c
index 7820293..361b17d 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ctldir.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ctldir.c
@@ -19,12 +19,10 @@
  * CDDL HEADER END
  */
 /*
- * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
+ * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 
-#pragma ident	"%Z%%M%	%I%	%E% SMI"
-
 /*
  * ZFS control directory (a.k.a. ".zfs")
  *
@@ -116,16 +114,21 @@ snapentry_compare(const void *a, const void *b)
 static struct vop_vector zfsctl_ops_root;
 static struct vop_vector zfsctl_ops_snapdir;
 static struct vop_vector zfsctl_ops_snapshot;
+static struct vop_vector zfsctl_ops_shares;
+static struct vop_vector zfsctl_ops_shares_dir;
 
 static vnode_t *zfsctl_mknode_snapdir(vnode_t *);
+static vnode_t *zfsctl_mknode_shares(vnode_t *);
 static vnode_t *zfsctl_snapshot_mknode(vnode_t *, uint64_t objset);
 static int zfsctl_unmount_snap(zfs_snapentry_t *, int, cred_t *);
 
 /*
- * Root directory elements.  We have only a single static entry, 'snapshot'.
+ * Root directory elements.  We only have two entries
+ * snapshot and shares.
  */
 static gfs_dirent_t zfsctl_root_entries[] = {
 	{ "snapshot", zfsctl_mknode_snapdir, GFS_CACHE_VNODE },
+	{ "shares", zfsctl_mknode_shares, GFS_CACHE_VNODE },
 	{ NULL }
 };
 
@@ -150,14 +153,21 @@ zfsctl_fini(void)
 }
 
 /*
- * Return the inode number associated with the 'snapshot' directory.
+ * Return the inode number associated with the 'snapshot' or
+ * 'shares' directory.
  */
 /* ARGSUSED */
 static ino64_t
 zfsctl_root_inode_cb(vnode_t *vp, int index)
 {
-	ASSERT(index == 0);
-	return (ZFSCTL_INO_SNAPDIR);
+	zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
+
+	ASSERT(index <= 2);
+
+	if (index == 0)
+		return (ZFSCTL_INO_SNAPDIR);
+
+	return (zfsvfs->z_shares_dir);
 }
 
 /*
@@ -260,8 +270,17 @@ zfsctl_common_access(ap)
 {
 	int mode = ap->a_accmode;
 
+#ifdef TODO
+	if (flags & V_ACE_MASK) {
+		if (accmode & ACE_ALL_WRITE_PERMS)
+			return (EACCES);
+	} else {
+#endif
 	if (mode & VWRITE)
 		return (EACCES);
+#ifdef TODO
+	}
+#endif
 
 	return (0);
 }
@@ -334,6 +353,36 @@ zfsctl_common_fid(ap)
 	return (0);
 }
 
+/*ARGSUSED*/
+static int
+zfsctl_shares_fid(ap)
+	struct vop_fid_args /* {
+		struct vnode *a_vp;
+		struct fid *a_fid;
+	} */ *ap;
+{
+	vnode_t		*vp = ap->a_vp;
+	fid_t		*fidp = (void *)ap->a_fid;
+	zfsvfs_t	*zfsvfs = vp->v_vfsp->vfs_data;
+	znode_t		*dzp;
+	int		error;
+
+	ZFS_ENTER(zfsvfs);
+
+	if (zfsvfs->z_shares_dir == 0) {
+		ZFS_EXIT(zfsvfs);
+		return (ENOTSUP);
+	}
+
+	if ((error = zfs_zget(zfsvfs, zfsvfs->z_shares_dir, &dzp)) == 0) {
+		error = VOP_FID(ZTOV(dzp), fidp);
+		VN_RELE(ZTOV(dzp));
+	}
+
+	ZFS_EXIT(zfsvfs);
+	return (error);
+}
+
 static int
 zfsctl_common_reclaim(ap)
 	struct vop_reclaim_args /* {
@@ -394,6 +443,41 @@ zfsctl_root_getattr(ap)
 	return (0);
 }
 
+#ifdef sun
+static int
+zfsctl_pathconf(vnode_t *vp, int cmd, ulong_t *valp, cred_t *cr,
+    caller_context_t *ct)
+{
+	/*
+	 * We only care about ACL_ENABLED so that libsec can
+	 * display ACL correctly and not default to POSIX draft.
+	 */
+	if (cmd == _PC_ACL_ENABLED) {
+		*valp = _ACL_ACE_ENABLED;
+		return (0);
+	}
+
+	return (fs_pathconf(vp, cmd, valp, cr, ct));
+}
+#endif	/* sun */
+
+#ifdef sun
+static const fs_operation_def_t zfsctl_tops_root[] = {
+	{ VOPNAME_OPEN,		{ .vop_open = zfsctl_common_open }	},
+	{ VOPNAME_CLOSE,	{ .vop_close = zfsctl_common_close }	},
+	{ VOPNAME_IOCTL,	{ .error = fs_inval }			},
+	{ VOPNAME_GETATTR,	{ .vop_getattr = zfsctl_root_getattr }	},
+	{ VOPNAME_ACCESS,	{ .vop_access = zfsctl_common_access }	},
+	{ VOPNAME_READDIR,	{ .vop_readdir = gfs_vop_readdir } 	},
+	{ VOPNAME_LOOKUP,	{ .vop_lookup = zfsctl_root_lookup }	},
+	{ VOPNAME_SEEK,		{ .vop_seek = fs_seek }			},
+	{ VOPNAME_INACTIVE,	{ .vop_inactive = gfs_vop_inactive }	},
+	{ VOPNAME_PATHCONF,	{ .vop_pathconf = zfsctl_pathconf }	},
+	{ VOPNAME_FID,		{ .vop_fid = zfsctl_common_fid	}	},
+	{ NULL }
+};
+#endif	/* sun */
+
 /*
  * Special case the handling of "..".
  */
@@ -712,7 +796,7 @@ zfsctl_snapdir_mkdir(vnode_t *dvp, char *dirname, vattr_t *vap, vnode_t  **vpp,
 		return (err);
 
 	if (err == 0) {
-		err = dmu_objset_snapshot(name, dirname, B_FALSE);
+		err = dmu_objset_snapshot(name, dirname, NULL, B_FALSE);
 		if (err)
 			return (err);
 		err = lookupnameat(dirname, seg, follow, NULL, vpp, dvp);
@@ -777,9 +861,6 @@ zfsctl_snapdir_lookup(ap)
 
 	ASSERT(dvp->v_type == VDIR);
 
-	if (gfs_lookup_dot(vpp, dvp, zfsvfs->z_ctldir, nm) == 0)
-		return (0);
-
 	*vpp = NULL;
 
 	/*
@@ -793,6 +874,11 @@ zfsctl_snapdir_lookup(ap)
 
 	ZFS_ENTER(zfsvfs);
 
+	if (gfs_lookup_dot(vpp, dvp, zfsvfs->z_ctldir, nm) == 0) {
+		ZFS_EXIT(zfsvfs);
+		return (0);
+	}
+
 	if (flags & FIGNORECASE) {
 		boolean_t conflict = B_FALSE;
 
@@ -904,6 +990,46 @@ domount:
 }
 
 /* ARGSUSED */
+int
+zfsctl_shares_lookup(ap)
+	struct vop_lookup_args /* {
+		struct vnode *a_dvp;
+		struct vnode **a_vpp;
+		struct componentname *a_cnp;
+	} */ *ap;
+{
+	vnode_t *dvp = ap->a_dvp;
+	vnode_t **vpp = ap->a_vpp;
+	struct componentname *cnp = ap->a_cnp;
+	zfsvfs_t *zfsvfs = dvp->v_vfsp->vfs_data;
+	char nm[NAME_MAX + 1];
+	znode_t *dzp;
+	int error;
+
+	ZFS_ENTER(zfsvfs);
+
+	ASSERT(cnp->cn_namelen < sizeof(nm));
+	strlcpy(nm, cnp->cn_nameptr, cnp->cn_namelen + 1);
+
+	if (gfs_lookup_dot(vpp, dvp, zfsvfs->z_ctldir, nm) == 0) {
+		ZFS_EXIT(zfsvfs);
+		return (0);
+	}
+
+	if (zfsvfs->z_shares_dir == 0) {
+		ZFS_EXIT(zfsvfs);
+		return (ENOTSUP);
+	}
+	if ((error = zfs_zget(zfsvfs, zfsvfs->z_shares_dir, &dzp)) == 0)
+		error = VOP_LOOKUP(ZTOV(dzp), vpp, cnp);
+
+	VN_RELE(ZTOV(dzp));
+	ZFS_EXIT(zfsvfs);
+
+	return (error);
+}
+
+/* ARGSUSED */
 static int
 zfsctl_snapdir_readdir_cb(vnode_t *vp, void *dp, int *eofp,
     offset_t *offp, offset_t *nextp, void *data, int flags)
@@ -947,6 +1073,44 @@ zfsctl_snapdir_readdir_cb(vnode_t *vp, void *dp, int *eofp,
 	return (0);
 }
 
+/* ARGSUSED */
+static int
+zfsctl_shares_readdir(ap)
+	struct vop_readdir_args /* {
+		struct vnode *a_vp;
+		struct uio *a_uio;
+		struct ucred *a_cred;
+		int *a_eofflag;
+		int *a_ncookies;
+		u_long **a_cookies;
+	} */ *ap;
+{
+	vnode_t *vp = ap->a_vp;
+	uio_t *uiop = ap->a_uio;
+	cred_t *cr = ap->a_cred;
+	int *eofp = ap->a_eofflag;
+	zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
+	znode_t *dzp;
+	int error;
+
+	ZFS_ENTER(zfsvfs);
+
+	if (zfsvfs->z_shares_dir == 0) {
+		ZFS_EXIT(zfsvfs);
+		return (ENOTSUP);
+	}
+	if ((error = zfs_zget(zfsvfs, zfsvfs->z_shares_dir, &dzp)) == 0) {
+		error = VOP_READDIR(ZTOV(dzp), uiop, cr, eofp, ap->a_ncookies, ap->a_cookies);
+		VN_RELE(ZTOV(dzp));
+	} else {
+		*eofp = 1;
+		error = ENOENT;
+	}
+
+	ZFS_EXIT(zfsvfs);
+	return (error);
+}
+
 /*
  * pvp is the '.zfs' directory (zfsctl_node_t).
  * Creates vp, which is '.zfs/snapshot' (zfsctl_snapdir_t).
@@ -973,6 +1137,51 @@ zfsctl_mknode_snapdir(vnode_t *pvp)
 	return (vp);
 }
 
+vnode_t *
+zfsctl_mknode_shares(vnode_t *pvp)
+{
+	vnode_t *vp;
+	zfsctl_node_t *sdp;
+
+	vp = gfs_dir_create(sizeof (zfsctl_node_t), pvp, pvp->v_vfsp,
+	    &zfsctl_ops_shares, NULL, NULL, MAXNAMELEN,
+	    NULL, NULL);
+	sdp = vp->v_data;
+	sdp->zc_cmtime = ((zfsctl_node_t *)pvp->v_data)->zc_cmtime;
+	return (vp);
+
+}
+
+/* ARGSUSED */
+static int
+zfsctl_shares_getattr(ap)
+	struct vop_getattr_args /* {
+		struct vnode *a_vp;
+		struct vattr *a_vap;
+		struct ucred *a_cred;
+		struct thread *a_td;
+	} */ *ap;
+{
+	vnode_t *vp = ap->a_vp;
+	vattr_t *vap = ap->a_vap;
+	cred_t *cr = ap->a_cred;
+	zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
+	znode_t *dzp;
+	int error;
+
+	ZFS_ENTER(zfsvfs);
+	if (zfsvfs->z_shares_dir == 0) {
+		ZFS_EXIT(zfsvfs);
+		return (ENOTSUP);
+	}
+	if ((error = zfs_zget(zfsvfs, zfsvfs->z_shares_dir, &dzp)) == 0) {
+		error = VOP_GETATTR(ZTOV(dzp), vap, cr);
+		VN_RELE(ZTOV(dzp));
+	}
+	ZFS_EXIT(zfsvfs);
+	return (error);
+}
+
 /* ARGSUSED */
 static int
 zfsctl_snapdir_getattr(ap)
@@ -1061,7 +1270,6 @@ zfsctl_snapshot_mknode(vnode_t *pvp, uint64_t objset)
 	VN_HOLD(vp);
 	zcp = vp->v_data;
 	zcp->zc_id = objset;
-	VFS_HOLD(vp->v_vfsp);
 	VOP_UNLOCK(vp, 0);
 
 	return (vp);
@@ -1112,7 +1320,6 @@ zfsctl_snapshot_inactive(ap)
 		mutex_exit(&sdp->sd_lock);
 	VN_RELE(dvp);
 end:
-	VFS_RELE(vp->v_vfsp);
 
 	/*
 	 * Dispose of the vnode for the snapshot mount point.