MFC r264835 (MFV r264829):

3897 zfs filesystem and snapshot limits

17 files changed, 986 insertions, 28 deletions

diff --git a/cddl/contrib/opensolaris/cmd/zfs/zfs.8 b/cddl/contrib/opensolaris/cmd/zfs/zfs.8
index d14ce13..b9760c4 100644
--- a/cddl/contrib/opensolaris/cmd/zfs/zfs.8
+++ b/cddl/contrib/opensolaris/cmd/zfs/zfs.8
@@ -24,13 +24,13 @@
 .\" Copyright (c) 2012, Bryan Drewery <bdrewery@FreeBSD.org>
 .\" Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
 .\" Copyright (c) 2013 Nexenta Systems, Inc. All Rights Reserved.
-.\" Copyright (c) 2013, Joyent, Inc. All rights reserved.
+.\" Copyright (c) 2014, Joyent, Inc. All rights reserved.
 .\" Copyright (c) 2013, Steven Hartland <smh@FreeBSD.org>
 .\" Copyright (c) 2014, Xin LI <delphij@FreeBSD.org>
 .\"
 .\" $FreeBSD$
 .\"
-.Dd April 5, 2014
+.Dd April 23, 2014
 .Dt ZFS 8
 .Os
 .Sh NAME
@@ -542,6 +542,13 @@ if the snapshot has been marked for deferred destroy by using the
 .Qq Nm Cm destroy -d
 command. Otherwise, the property is
 .Cm off .
+.It Sy filesystem_count
+The total number of filesystems and volumes that exist under this location in the
+dataset tree.
+This value is only available when a
+.Sy filesystem_limit
+has
+been set somewhere in the tree under which the dataset resides.
 .It Sy logicalreferenced
 The amount of space that is
 .Qq logically
@@ -600,6 +607,12 @@ The compression ratio achieved for the
 space of this dataset, expressed as a multiplier.  See also the
 .Sy compressratio
 property.
+.It Sy snapshot_count
+The total number of snapshots that exist under this location in the dataset tree.
+This value is only available when a
+.Sy snapshot_limit
+has been set somewhere
+in the tree under which the dataset resides.
 .It Sy type
 The type of dataset:
 .Sy filesystem , volume , No or Sy snapshot .
@@ -1020,6 +1033,23 @@ The
 .Sy mlslabel
 property is currently not supported on
 .Fx .
+.It Sy filesystem_limit Ns = Ns Ar count | Cm none
+Limits the number of filesystems and volumes that can exist under this point in
+the dataset tree.
+The limit is not enforced if the user is allowed to change
+the limit.
+Setting a
+.Sy filesystem_limit
+on a descendent of a filesystem that
+already has a
+.Sy filesystem_limit
+does not override the ancestor's
+.Sy filesystem_limit ,
+but rather imposes an additional limit.
+This feature must be enabled to be used
+.Po see
+.Xr zpool-features 7
+.Pc .
 .It Sy mountpoint Ns = Ns Ar path | Cm none | legacy
 Controls the mount point used for this file system. See the
 .Qq Sx Mount Points
@@ -1061,6 +1091,27 @@ the ancestor's quota, but rather imposes an additional limit.
 Quotas cannot be set on volumes, as the
 .Sy volsize
 property acts as an implicit quota.
+.It Sy snapshot_limit Ns = Ns Ar count | Cm none
+Limits the number of snapshots that can be created on a dataset and its
+descendents.
+Setting a
+.Sy snapshot_limit
+on a descendent of a dataset that already
+has a
+.Sy snapshot_limit
+does not override the ancestor's
+.Sy snapshot_limit ,
+but
+rather imposes an additional limit.
+The limit is not enforced if the user is
+allowed to change the limit.
+For example, this means that recursive snapshots
+taken from the global zone are counted against each delegated dataset within
+a jail.
+This feature must be enabled to be used
+.Po see
+.Xr zpool-features 7
+.Pc .
 .It Sy userquota@ Ns Ar user Ns = Ns Ar size | Cm none
 Limits the amount of space consumed by the specified user.
 Similar to the
@@ -2738,6 +2789,7 @@ protocol
 .It dedup Ta property
 .It devices Ta property
 .It exec Ta property
+.It filesystem_limit Ta property
 .It logbias Ta property
 .It jailed Ta property
 .It mlslabel Ta property
@@ -2756,6 +2808,7 @@ protocol
 .It sharenfs Ta property
 .It sharesmb Ta property
 .It snapdir Ta property
+.It snapshot_limit Ta property
 .It sync Ta property
 .It utf8only Ta property
 .It version Ta property
@@ -3102,10 +3155,12 @@ pool/home/bob  compression           on                     local
 pool/home/bob  atime                 on                     default
 pool/home/bob  devices               on                     default
 pool/home/bob  exec                  on                     default
+pool/home/bob  filesystem_limit      none                   default
 pool/home/bob  setuid                on                     default
 pool/home/bob  readonly              off                    default
 pool/home/bob  jailed                off                    default
 pool/home/bob  snapdir               hidden                 default
+pool/home/bob  snapshot_limit        none                   default
 pool/home/bob  aclmode               discard                default
 pool/home/bob  aclinherit            restricted             default
 pool/home/bob  canmount              on                     default
diff --git a/cddl/contrib/opensolaris/cmd/zpool/zpool-features.7 b/cddl/contrib/opensolaris/cmd/zpool/zpool-features.7
index 5c6c47a..f9d866b 100644
--- a/cddl/contrib/opensolaris/cmd/zpool/zpool-features.7
+++ b/cddl/contrib/opensolaris/cmd/zpool/zpool-features.7
@@ -23,7 +23,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd January 2, 2014
+.Dd April 23, 2014
 .Dt ZPOOL-FEATURES 7
 .Os
 .Sh NAME
@@ -187,6 +187,23 @@ This feature is
 .Sy active
 while there are any filesystems, volumes, or snapshots which were created
 after enabling this feature.
+.It Sy filesystem_limits
+.Bl -column "READ\-ONLY COMPATIBLE" "com.joyent:filesystem_limits"
+.It GUID Ta com.joyent:filesystem_limits
+.It READ\-ONLY COMPATIBLE Ta yes
+.It DEPENDENCIES Ta extensible_dataset
+.El
+.Pp
+This feature enables filesystem and snapshot limits.
+These limits can be used
+to control how many filesystems and/or snapshots can be created at the point in
+the tree on which the limits are set.
+.Pp
+This feature is
+.Sy active
+once either of the limit properties has been
+set on a dataset.
+Once activated the feature is never deactivated.
 .It Sy lz4_compress
 .Bl -column "READ\-ONLY COMPATIBLE" "org.illumos:lz4_compress"
 .It GUID Ta org.illumos:lz4_compress
diff --git a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_dataset.c b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_dataset.c
index abde59b..5377cbd 100644
--- a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_dataset.c
+++ b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_dataset.c
@@ -21,6 +21,7 @@
 
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2013, Joyent, Inc. All rights reserved.
  * Copyright (c) 2013 by Delphix. All rights reserved.
  * Copyright (c) 2012 DEY Storage Systems, Inc.  All rights reserved.
  * Copyright (c) 2011-2012 Pawel Jakub Dawidek <pawel@dawidek.net>.
@@ -1910,6 +1911,10 @@ get_numeric_property(zfs_handle_t *zhp, zfs_prop_t prop, zprop_source_t *src,
 	case ZFS_PROP_REFQUOTA:
 	case ZFS_PROP_RESERVATION:
 	case ZFS_PROP_REFRESERVATION:
+	case ZFS_PROP_FILESYSTEM_LIMIT:
+	case ZFS_PROP_SNAPSHOT_LIMIT:
+	case ZFS_PROP_FILESYSTEM_COUNT:
+	case ZFS_PROP_SNAPSHOT_COUNT:
 		*val = getprop_uint64(zhp, prop, source);
 
 		if (*source == NULL) {
@@ -2315,6 +2320,30 @@ zfs_prop_get(zfs_handle_t *zhp, zfs_prop_t prop, char *propbuf, size_t proplen,
 		}
 		break;
 
+	case ZFS_PROP_FILESYSTEM_LIMIT:
+	case ZFS_PROP_SNAPSHOT_LIMIT:
+	case ZFS_PROP_FILESYSTEM_COUNT:
+	case ZFS_PROP_SNAPSHOT_COUNT:
+
+		if (get_numeric_property(zhp, prop, src, &source, &val) != 0)
+			return (-1);
+
+		/*
+		 * If limit is UINT64_MAX, we translate this into 'none' (unless
+		 * literal is set), and indicate that it's the default value.
+		 * Otherwise, we print the number nicely and indicate that it's
+		 * set locally.
+		 */
+		if (literal) {
+			(void) snprintf(propbuf, proplen, "%llu",
+			    (u_longlong_t)val);
+		} else if (val == UINT64_MAX) {
+			(void) strlcpy(propbuf, "none", proplen);
+		} else {
+			zfs_nicenum(val, propbuf, proplen);
+		}
+		break;
+
 	case ZFS_PROP_REFRATIO:
 	case ZFS_PROP_COMPRESSRATIO:
 		if (get_numeric_property(zhp, prop, src, &source, &val) != 0)
diff --git a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_util.c b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_util.c
index 6823c07..3b59914 100644
--- a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_util.c
+++ b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_util.c
@@ -21,6 +21,7 @@
 
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2013, Joyent, Inc. All rights reserved.
  * Copyright (c) 2012 by Delphix. All rights reserved.
  */
 
@@ -1268,6 +1269,16 @@ zprop_parse_value(libzfs_handle_t *hdl, nvpair_t *elem, int prop,
 			    "use 'none' to disable quota/refquota"));
 			goto error;
 		}
+
+		/*
+		 * Special handling for "*_limit=none". In this case it's not
+		 * 0 but UINT64_MAX.
+		 */
+		if ((type & ZFS_TYPE_DATASET) && isnone &&
+		    (prop == ZFS_PROP_FILESYSTEM_LIMIT ||
+		    prop == ZFS_PROP_SNAPSHOT_LIMIT)) {
+			*ivalp = UINT64_MAX;
+		}
 		break;
 
 	case PROP_TYPE_INDEX:
diff --git a/sys/cddl/contrib/opensolaris/common/zfs/zfeature_common.c b/sys/cddl/contrib/opensolaris/common/zfs/zfeature_common.c
index 28b0c9e..5aa9d2b 100644
--- a/sys/cddl/contrib/opensolaris/common/zfs/zfeature_common.c
+++ b/sys/cddl/contrib/opensolaris/common/zfs/zfeature_common.c
@@ -205,4 +205,13 @@ zpool_feature_init(void)
 	    "com.delphix:bookmarks", "bookmarks",
 	    "\"zfs bookmark\" command",
 	    B_TRUE, B_FALSE, B_FALSE, bookmarks_deps);
+
+	static const spa_feature_t filesystem_limits_deps[] = {
+	    SPA_FEATURE_EXTENSIBLE_DATASET,
+	    SPA_FEATURE_NONE
+	};
+	zfeature_register(SPA_FEATURE_FS_SS_LIMIT,
+	    "com.joyent:filesystem_limits", "filesystem_limits",
+	    "Filesystem and snapshot limits.", B_TRUE, B_FALSE, B_FALSE,
+	    filesystem_limits_deps);
 }
diff --git a/sys/cddl/contrib/opensolaris/common/zfs/zfeature_common.h b/sys/cddl/contrib/opensolaris/common/zfs/zfeature_common.h
index fc5bdc5..1f668a5 100644
--- a/sys/cddl/contrib/opensolaris/common/zfs/zfeature_common.h
+++ b/sys/cddl/contrib/opensolaris/common/zfs/zfeature_common.h
@@ -48,6 +48,7 @@ typedef enum spa_feature {
 	SPA_FEATURE_HOLE_BIRTH,
 	SPA_FEATURE_EXTENSIBLE_DATASET,
 	SPA_FEATURE_BOOKMARKS,
+	SPA_FEATURE_FS_SS_LIMIT,
 	SPA_FEATURES
 } spa_feature_t;
 
diff --git a/sys/cddl/contrib/opensolaris/common/zfs/zfs_prop.c b/sys/cddl/contrib/opensolaris/common/zfs/zfs_prop.c
index fde51a7..141e226 100644
--- a/sys/cddl/contrib/opensolaris/common/zfs/zfs_prop.c
+++ b/sys/cddl/contrib/opensolaris/common/zfs/zfs_prop.c
@@ -383,6 +383,18 @@ zfs_prop_init(void)
 	zprop_register_number(ZFS_PROP_REFRESERVATION, "refreservation", 0,
 	    PROP_DEFAULT, ZFS_TYPE_FILESYSTEM | ZFS_TYPE_VOLUME,
 	    "<size> | none", "REFRESERV");
+	zprop_register_number(ZFS_PROP_FILESYSTEM_LIMIT, "filesystem_limit",
+	    UINT64_MAX, PROP_DEFAULT, ZFS_TYPE_FILESYSTEM,
+	    "<count> | none", "FSLIMIT");
+	zprop_register_number(ZFS_PROP_SNAPSHOT_LIMIT, "snapshot_limit",
+	    UINT64_MAX, PROP_DEFAULT, ZFS_TYPE_FILESYSTEM | ZFS_TYPE_VOLUME,
+	    "<count> | none", "SSLIMIT");
+	zprop_register_number(ZFS_PROP_FILESYSTEM_COUNT, "filesystem_count",
+	    UINT64_MAX, PROP_DEFAULT, ZFS_TYPE_FILESYSTEM,
+	    "<count>", "FSCOUNT");
+	zprop_register_number(ZFS_PROP_SNAPSHOT_COUNT, "snapshot_count",
+	    UINT64_MAX, PROP_DEFAULT, ZFS_TYPE_FILESYSTEM | ZFS_TYPE_VOLUME,
+	    "<count>", "SSCOUNT");
 
 	/* inherit number properties */
 	zprop_register_number(ZFS_PROP_RECORDSIZE, "recordsize",
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_objset.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_objset.c
index b5c0f5f..0c4fe26 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_objset.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_objset.c
@@ -22,6 +22,7 @@
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2013 by Delphix. All rights reserved.
  * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
+ * Copyright (c) 2013, Joyent, Inc. All rights reserved.
  */
 
 /* Portions Copyright 2010 Robert Milkowski */
@@ -758,9 +759,11 @@ dmu_objset_create_check(void *arg, dmu_tx_t *tx)
 		dsl_dir_rele(pdd, FTAG);
 		return (SET_ERROR(EEXIST));
 	}
+	error = dsl_fs_ss_limit_check(pdd, 1, ZFS_PROP_FILESYSTEM_LIMIT, NULL,
+	    doca->doca_cred);
 	dsl_dir_rele(pdd, FTAG);
 
-	return (0);
+	return (error);
 }
 
 static void
@@ -844,6 +847,12 @@ dmu_objset_clone_check(void *arg, dmu_tx_t *tx)
 		dsl_dir_rele(pdd, FTAG);
 		return (SET_ERROR(EXDEV));
 	}
+	error = dsl_fs_ss_limit_check(pdd, 1, ZFS_PROP_FILESYSTEM_LIMIT, NULL,
+	    doca->doca_cred);
+	if (error != 0) {
+		dsl_dir_rele(pdd, FTAG);
+		return (SET_ERROR(EDQUOT));
+	}
 	dsl_dir_rele(pdd, FTAG);
 
 	error = dsl_dataset_hold(dp, doca->doca_origin, FTAG, &origin);
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c
index ea6d3b4..d3efa55 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c
@@ -22,7 +22,7 @@
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
  * Copyright (c) 2013 by Delphix. All rights reserved.
- * Copyright (c) 2012, Joyent, Inc. All rights reserved.
+ * Copyright (c) 2014, Joyent, Inc. All rights reserved.
  * Copyright (c) 2012, Martin Matuska <mm@FreeBSD.org>. All rights reserved.
  */
 
@@ -806,6 +806,20 @@ recv_begin_check_existing_impl(dmu_recv_begin_arg_t *drba, dsl_dataset_t *ds,
 	if (error != ENOENT)
 		return (error == 0 ? EEXIST : error);
 
+	/*
+	 * Check snapshot limit before receiving. We'll recheck again at the
+	 * end, but might as well abort before receiving if we're already over
+	 * the limit.
+	 *
+	 * Note that we do not check the file system limit with
+	 * dsl_dir_fscount_check because the temporary %clones don't count
+	 * against that limit.
+	 */
+	error = dsl_fs_ss_limit_check(ds->ds_dir, 1, ZFS_PROP_SNAPSHOT_LIMIT,
+	    NULL, drba->drba_cred);
+	if (error != 0)
+		return (error);
+
 	if (fromguid != 0) {
 		dsl_dataset_t *snap;
 		uint64_t obj = ds->ds_phys->ds_prev_snap_obj;
@@ -912,6 +926,25 @@ dmu_recv_begin_check(void *arg, dmu_tx_t *tx)
 		if (error != 0)
 			return (error);
 
+		/*
+		 * Check filesystem and snapshot limits before receiving. We'll
+		 * recheck snapshot limits again at the end (we create the
+		 * filesystems and increment those counts during begin_sync).
+		 */
+		error = dsl_fs_ss_limit_check(ds->ds_dir, 1,
+		    ZFS_PROP_FILESYSTEM_LIMIT, NULL, drba->drba_cred);
+		if (error != 0) {
+			dsl_dataset_rele(ds, FTAG);
+			return (error);
+		}
+
+		error = dsl_fs_ss_limit_check(ds->ds_dir, 1,
+		    ZFS_PROP_SNAPSHOT_LIMIT, NULL, drba->drba_cred);
+		if (error != 0) {
+			dsl_dataset_rele(ds, FTAG);
+			return (error);
+		}
+
 		if (drba->drba_origin != NULL) {
 			dsl_dataset_t *origin;
 			error = dsl_dataset_hold(dp, drba->drba_origin,
@@ -1021,6 +1054,7 @@ dmu_recv_begin(char *tofs, char *tosnap, struct drr_begin *drrb,
 	drc->drc_tosnap = tosnap;
 	drc->drc_tofs = tofs;
 	drc->drc_force = force;
+	drc->drc_cred = CRED();
 
 	if (drrb->drr_magic == BSWAP_64(DMU_BACKUP_MAGIC))
 		drc->drc_byteswap = B_TRUE;
@@ -1740,7 +1774,7 @@ dmu_recv_end_check(void *arg, dmu_tx_t *tx)
 			return (error);
 		}
 		error = dsl_dataset_snapshot_check_impl(origin_head,
-		    drc->drc_tosnap, tx, B_TRUE);
+		    drc->drc_tosnap, tx, B_TRUE, 1, drc->drc_cred);
 		dsl_dataset_rele(origin_head, FTAG);
 		if (error != 0)
 			return (error);
@@ -1748,7 +1782,7 @@ dmu_recv_end_check(void *arg, dmu_tx_t *tx)
 		error = dsl_destroy_head_check_impl(drc->drc_ds, 1);
 	} else {
 		error = dsl_dataset_snapshot_check_impl(drc->drc_ds,
-		    drc->drc_tosnap, tx, B_TRUE);
+		    drc->drc_tosnap, tx, B_TRUE, 1, drc->drc_cred);
 	}
 	return (error);
 }
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c
index 6efbfb7..4172397 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c
@@ -22,7 +22,7 @@
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Portions Copyright (c) 2011 Martin Matuska <mm@FreeBSD.org>
  * Copyright (c) 2013 by Delphix. All rights reserved.
- * Copyright (c) 2012, Joyent, Inc. All rights reserved.
+ * Copyright (c) 2014, Joyent, Inc. All rights reserved.
  * Copyright (c) 2014 RackTop Systems.
  */
 
@@ -321,7 +321,8 @@ dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value)
 }
 
 int
-dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx)
+dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx,
+    boolean_t adj_cnt)
 {
 	objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
 	uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj;
@@ -338,6 +339,11 @@ dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx)
 	err = zap_remove_norm(mos, snapobj, name, mt, tx);
 	if (err == ENOTSUP && mt == MT_FIRST)
 		err = zap_remove(mos, snapobj, name, tx);
+
+	if (err == 0 && adj_cnt)
+		dsl_fs_ss_count_adjust(ds->ds_dir, -1,
+		    DD_FIELD_SNAPSHOT_COUNT, tx);
+
 	return (err);
 }
 
@@ -765,6 +771,21 @@ dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname,
 
 	dsl_deleg_set_create_perms(dd, tx, cr);
 
+	/*
+	 * Since we're creating a new node we know it's a leaf, so we can
+	 * initialize the counts if the limit feature is active.
+	 */
+	if (spa_feature_is_active(dp->dp_spa, SPA_FEATURE_FS_SS_LIMIT)) {
+		uint64_t cnt = 0;
+		objset_t *os = dd->dd_pool->dp_meta_objset;
+
+		dsl_dir_zapify(dd, tx);
+		VERIFY0(zap_add(os, dd->dd_object, DD_FIELD_FILESYSTEM_COUNT,
+		    sizeof (cnt), 1, &cnt, tx));
+		VERIFY0(zap_add(os, dd->dd_object, DD_FIELD_SNAPSHOT_COUNT,
+		    sizeof (cnt), 1, &cnt, tx));
+	}
+
 	dsl_dir_rele(dd, FTAG);
 
 	/*
@@ -971,11 +992,12 @@ typedef struct dsl_dataset_snapshot_arg {
 	nvlist_t *ddsa_snaps;
 	nvlist_t *ddsa_props;
 	nvlist_t *ddsa_errors;
+	cred_t *ddsa_cr;
 } dsl_dataset_snapshot_arg_t;
 
 int
 dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname,
-    dmu_tx_t *tx, boolean_t recv)
+    dmu_tx_t *tx, boolean_t recv, uint64_t cnt, cred_t *cr)
 {
 	int error;
 	uint64_t value;
@@ -1013,6 +1035,18 @@ dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname,
 	if (!recv && DS_IS_INCONSISTENT(ds))
 		return (SET_ERROR(EBUSY));
 
+	/*
+	 * Skip the check for temporary snapshots or if we have already checked
+	 * the counts in dsl_dataset_snapshot_check. This means we really only
+	 * check the count here when we're receiving a stream.
+	 */
+	if (cnt != 0 && cr != NULL) {
+		error = dsl_fs_ss_limit_check(ds->ds_dir, cnt,
+		    ZFS_PROP_SNAPSHOT_LIMIT, NULL, cr);
+		if (error != 0)
+			return (error);
+	}
+
 	error = dsl_dataset_snapshot_reserve_space(ds, tx);
 	if (error != 0)
 		return (error);
@@ -1028,6 +1062,99 @@ dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx)
 	nvpair_t *pair;
 	int rv = 0;
 
+	/*
+	 * Pre-compute how many total new snapshots will be created for each
+	 * level in the tree and below. This is needed for validating the
+	 * snapshot limit when either taking a recursive snapshot or when
+	 * taking multiple snapshots.
+	 *
+	 * The problem is that the counts are not actually adjusted when
+	 * we are checking, only when we finally sync. For a single snapshot,
+	 * this is easy, the count will increase by 1 at each node up the tree,
+	 * but its more complicated for the recursive/multiple snapshot case.
+	 *
+	 * The dsl_fs_ss_limit_check function does recursively check the count
+	 * at each level up the tree but since it is validating each snapshot
+	 * independently we need to be sure that we are validating the complete
+	 * count for the entire set of snapshots. We do this by rolling up the
+	 * counts for each component of the name into an nvlist and then
+	 * checking each of those cases with the aggregated count.
+	 *
+	 * This approach properly handles not only the recursive snapshot
+	 * case (where we get all of those on the ddsa_snaps list) but also
+	 * the sibling case (e.g. snapshot a/b and a/c so that we will also
+	 * validate the limit on 'a' using a count of 2).
+	 *
+	 * We validate the snapshot names in the third loop and only report
+	 * name errors once.
+	 */
+	if (dmu_tx_is_syncing(tx)) {
+		nvlist_t *cnt_track = NULL;
+		cnt_track = fnvlist_alloc();
+
+		/* Rollup aggregated counts into the cnt_track list */
+		for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL);
+		    pair != NULL;
+		    pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) {
+			char *pdelim;
+			uint64_t val;
+			char nm[MAXPATHLEN];
+
+			(void) strlcpy(nm, nvpair_name(pair), sizeof (nm));
+			pdelim = strchr(nm, '@');
+			if (pdelim == NULL)
+				continue;
+			*pdelim = '\0';
+
+			do {
+				if (nvlist_lookup_uint64(cnt_track, nm,
+				    &val) == 0) {
+					/* update existing entry */
+					fnvlist_add_uint64(cnt_track, nm,
+					    val + 1);
+				} else {
+					/* add to list */
+					fnvlist_add_uint64(cnt_track, nm, 1);
+				}
+
+				pdelim = strrchr(nm, '/');
+				if (pdelim != NULL)
+					*pdelim = '\0';
+			} while (pdelim != NULL);
+		}
+
+		/* Check aggregated counts at each level */
+		for (pair = nvlist_next_nvpair(cnt_track, NULL);
+		    pair != NULL; pair = nvlist_next_nvpair(cnt_track, pair)) {
+			int error = 0;
+			char *name;
+			uint64_t cnt = 0;
+			dsl_dataset_t *ds;
+
+			name = nvpair_name(pair);
+			cnt = fnvpair_value_uint64(pair);
+			ASSERT(cnt > 0);
+
+			error = dsl_dataset_hold(dp, name, FTAG, &ds);
+			if (error == 0) {
+				error = dsl_fs_ss_limit_check(ds->ds_dir, cnt,
+				    ZFS_PROP_SNAPSHOT_LIMIT, NULL,
+				    ddsa->ddsa_cr);
+				dsl_dataset_rele(ds, FTAG);
+			}
+
+			if (error != 0) {
+				if (ddsa->ddsa_errors != NULL)
+					fnvlist_add_int32(ddsa->ddsa_errors,
+					    name, error);
+				rv = error;
+				/* only report one error for this check */
+				break;
+			}
+		}
+		nvlist_free(cnt_track);
+	}
+
 	for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL);
 	    pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) {
 		int error = 0;
@@ -1048,8 +1175,9 @@ dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx)
 		if (error == 0)
 			error = dsl_dataset_hold(dp, dsname, FTAG, &ds);
 		if (error == 0) {
+			/* passing 0/NULL skips dsl_fs_ss_limit_check */
 			error = dsl_dataset_snapshot_check_impl(ds,
-			    atp + 1, tx, B_FALSE);
+			    atp + 1, tx, B_FALSE, 0, NULL);
 			dsl_dataset_rele(ds, FTAG);
 		}
 
@@ -1061,6 +1189,7 @@ dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx)
 			rv = error;
 		}
 	}
+
 	return (rv);
 }
 
@@ -1088,6 +1217,7 @@ dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname,
 	    bcmp(&os->os_phys->os_zil_header, &zero_zil,
 	    sizeof (zero_zil)) == 0);
 
+	dsl_fs_ss_count_adjust(ds->ds_dir, 1, DD_FIELD_SNAPSHOT_COUNT, tx);
 
 	/*
 	 * The origin's ds_creation_txg has to be < TXG_INITIAL
@@ -1266,6 +1396,7 @@ dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors)
 	ddsa.ddsa_snaps = snaps;
 	ddsa.ddsa_props = props;
 	ddsa.ddsa_errors = errors;
+	ddsa.ddsa_cr = CRED();
 
 	if (error == 0) {
 		error = dsl_sync_task(firstname, dsl_dataset_snapshot_check,
@@ -1315,8 +1446,9 @@ dsl_dataset_snapshot_tmp_check(void *arg, dmu_tx_t *tx)
 	if (error != 0)
 		return (error);
 
+	/* NULL cred means no limit check for tmp snapshot */
 	error = dsl_dataset_snapshot_check_impl(ds, ddsta->ddsta_snapname,
-	    tx, B_FALSE);
+	    tx, B_FALSE, 0, NULL);
 	if (error != 0) {
 		dsl_dataset_rele(ds, FTAG);
 		return (error);
@@ -1689,7 +1821,8 @@ dsl_dataset_rename_snapshot_sync_impl(dsl_pool_t *dp,
 	spa_history_log_internal_ds(ds, "rename", tx,
 	    "-> @%s", ddrsa->ddrsa_newsnapname);
 
-	VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx));
+	VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx,
+	    B_FALSE));
 	mutex_enter(&ds->ds_lock);
 	(void) strcpy(ds->ds_snapname, ddrsa->ddrsa_newsnapname);
 	mutex_exit(&ds->ds_lock);
@@ -1936,6 +2069,7 @@ typedef struct dsl_dataset_promote_arg {
 	dsl_dataset_t *origin_origin; /* origin of the origin */
 	uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap;
 	char *err_ds;
+	cred_t *cr;
 } dsl_dataset_promote_arg_t;
 
 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep);
@@ -1953,6 +2087,7 @@ dsl_dataset_promote_check(void *arg, dmu_tx_t *tx)
 	dsl_dataset_t *origin_ds;
 	int err;
 	uint64_t unused;
+	uint64_t ss_mv_cnt;
 
 	err = promote_hold(ddpa, dp, FTAG);
 	if (err != 0)
@@ -1999,6 +2134,7 @@ dsl_dataset_promote_check(void *arg, dmu_tx_t *tx)
 	 * Note however, if we stop before we reach the ORIGIN we get:
 	 * uN + kN + kN-1 + ... + kM - uM-1
 	 */
+	ss_mv_cnt = 0;
 	ddpa->used = origin_ds->ds_phys->ds_referenced_bytes;
 	ddpa->comp = origin_ds->ds_phys->ds_compressed_bytes;
 	ddpa->uncomp = origin_ds->ds_phys->ds_uncompressed_bytes;
@@ -2007,6 +2143,8 @@ dsl_dataset_promote_check(void *arg, dmu_tx_t *tx)
 		uint64_t val, dlused, dlcomp, dluncomp;
 		dsl_dataset_t *ds = snap->ds;
 
+		ss_mv_cnt++;
+
 		/*
 		 * If there are long holds, we won't be able to evict
 		 * the objset.
@@ -2049,9 +2187,9 @@ dsl_dataset_promote_check(void *arg, dmu_tx_t *tx)
 		    ddpa->origin_origin->ds_phys->ds_uncompressed_bytes;
 	}
 
-	/* Check that there is enough space here */
+	/* Check that there is enough space and limit headroom here */
 	err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir,
-	    ddpa->used);
+	    0, ss_mv_cnt, ddpa->used, ddpa->cr);
 	if (err != 0)
 		goto out;
 
@@ -2191,10 +2329,12 @@ dsl_dataset_promote_sync(void *arg, dmu_tx_t *tx)
 		/* move snap name entry */
 		VERIFY0(dsl_dataset_get_snapname(ds));
 		VERIFY0(dsl_dataset_snap_remove(origin_head,
-		    ds->ds_snapname, tx));
+		    ds->ds_snapname, tx, B_TRUE));
 		VERIFY0(zap_add(dp->dp_meta_objset,
 		    hds->ds_phys->ds_snapnames_zapobj, ds->ds_snapname,
 		    8, 1, &ds->ds_object, tx));
+		dsl_fs_ss_count_adjust(hds->ds_dir, 1,
+		    DD_FIELD_SNAPSHOT_COUNT, tx);
 
 		/* change containing dsl_dir */
 		dmu_buf_will_dirty(ds->ds_dbuf, tx);
@@ -2432,6 +2572,7 @@ dsl_dataset_promote(const char *name, char *conflsnap)
 
 	ddpa.ddpa_clonename = name;
 	ddpa.err_ds = conflsnap;
+	ddpa.cr = CRED();
 
 	return (dsl_sync_task(name, dsl_dataset_promote_check,
 	    dsl_dataset_promote_sync, &ddpa, 2 + numsnaps));
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_destroy.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_destroy.c
index 9e695cd..639412c 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_destroy.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_destroy.c
@@ -22,6 +22,7 @@
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2013 by Delphix. All rights reserved.
  * Copyright (c) 2013 Steven Hartland. All rights reserved.
+ * Copyright (c) 2013 by Joyent, Inc. All rights reserved.
  */
 
 #include <sys/zfs_context.h>
@@ -430,7 +431,7 @@ dsl_destroy_snapshot_sync_impl(dsl_dataset_t *ds, boolean_t defer, dmu_tx_t *tx)
 		ASSERT3U(val, ==, obj);
 	}
 #endif
-	VERIFY0(dsl_dataset_snap_remove(ds_head, ds->ds_snapname, tx));
+	VERIFY0(dsl_dataset_snap_remove(ds_head, ds->ds_snapname, tx, B_TRUE));
 	dsl_dataset_rele(ds_head, FTAG);
 
 	if (ds_prev != NULL)
@@ -657,6 +658,17 @@ dsl_dir_destroy_sync(uint64_t ddobj, dmu_tx_t *tx)
 	ASSERT0(dd->dd_phys->dd_head_dataset_obj);
 
 	/*
+	 * Decrement the filesystem count for all parent filesystems.
+	 *
+	 * When we receive an incremental stream into a filesystem that already
+	 * exists, a temporary clone is created.  We never count this temporary
+	 * clone, whose name begins with a '%'.
+	 */
+	if (dd->dd_myname[0] != '%' && dd->dd_parent != NULL)
+		dsl_fs_ss_count_adjust(dd->dd_parent, -1,
+		    DD_FIELD_FILESYSTEM_COUNT, tx);
+
+	/*
 	 * Remove our reservation. The impl() routine avoids setting the
 	 * actual property, which would require the (already destroyed) ds.
 	 */
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c
index c8de009..d61dbc1 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c
@@ -23,6 +23,7 @@
  * Copyright (c) 2011 Pawel Jakub Dawidek <pawel@dawidek.net>.
  * All rights reserved.
  * Copyright (c) 2013 by Delphix. All rights reserved.
+ * Copyright (c) 2014 Joyent, Inc. All rights reserved.
  */
 
 #include <sys/dmu.h>
@@ -44,7 +45,86 @@
 #ifdef _KERNEL
 #include <sys/zfs_vfsops.h>
 #endif
+#include <sys/zfeature.h>
+#include <sys/policy.h>
+#include <sys/zfs_znode.h>
 #include "zfs_namecheck.h"
+#include "zfs_prop.h"
+
+/*
+ * Filesystem and Snapshot Limits
+ * ------------------------------
+ *
+ * These limits are used to restrict the number of filesystems and/or snapshots
+ * that can be created at a given level in the tree or below. A typical
+ * use-case is with a delegated dataset where the administrator wants to ensure
+ * that a user within the zone is not creating too many additional filesystems
+ * or snapshots, even though they're not exceeding their space quota.
+ *
+ * The filesystem and snapshot counts are stored as extensible properties. This
+ * capability is controlled by a feature flag and must be enabled to be used.
+ * Once enabled, the feature is not active until the first limit is set. At
+ * that point, future operations to create/destroy filesystems or snapshots
+ * will validate and update the counts.
+ *
+ * Because the count properties will not exist before the feature is active,
+ * the counts are updated when a limit is first set on an uninitialized
+ * dsl_dir node in the tree (The filesystem/snapshot count on a node includes
+ * all of the nested filesystems/snapshots. Thus, a new leaf node has a
+ * filesystem count of 0 and a snapshot count of 0. Non-existent filesystem and
+ * snapshot count properties on a node indicate uninitialized counts on that
+ * node.) When first setting a limit on an uninitialized node, the code starts
+ * at the filesystem with the new limit and descends into all sub-filesystems
+ * to add the count properties.
+ *
+ * In practice this is lightweight since a limit is typically set when the
+ * filesystem is created and thus has no children. Once valid, changing the
+ * limit value won't require a re-traversal since the counts are already valid.
+ * When recursively fixing the counts, if a node with a limit is encountered
+ * during the descent, the counts are known to be valid and there is no need to
+ * descend into that filesystem's children. The counts on filesystems above the
+ * one with the new limit will still be uninitialized, unless a limit is
+ * eventually set on one of those filesystems. The counts are always recursively
+ * updated when a limit is set on a dataset, unless there is already a limit.
+ * When a new limit value is set on a filesystem with an existing limit, it is
+ * possible for the new limit to be less than the current count at that level
+ * since a user who can change the limit is also allowed to exceed the limit.
+ *
+ * Once the feature is active, then whenever a filesystem or snapshot is
+ * created, the code recurses up the tree, validating the new count against the
+ * limit at each initialized level. In practice, most levels will not have a
+ * limit set. If there is a limit at any initialized level up the tree, the
+ * check must pass or the creation will fail. Likewise, when a filesystem or
+ * snapshot is destroyed, the counts are recursively adjusted all the way up
+ * the initizized nodes in the tree. Renaming a filesystem into different point
+ * in the tree will first validate, then update the counts on each branch up to
+ * the common ancestor. A receive will also validate the counts and then update
+ * them.
+ *
+ * An exception to the above behavior is that the limit is not enforced if the
+ * user has permission to modify the limit. This is primarily so that
+ * recursive snapshots in the global zone always work. We want to prevent a
+ * denial-of-service in which a lower level delegated dataset could max out its
+ * limit and thus block recursive snapshots from being taken in the global zone.
+ * Because of this, it is possible for the snapshot count to be over the limit
+ * and snapshots taken in the global zone could cause a lower level dataset to
+ * hit or exceed its limit. The administrator taking the global zone recursive
+ * snapshot should be aware of this side-effect and behave accordingly.
+ * For consistency, the filesystem limit is also not enforced if the user can
+ * modify the limit.
+ *
+ * The filesystem and snapshot limits are validated by dsl_fs_ss_limit_check()
+ * and updated by dsl_fs_ss_count_adjust(). A new limit value is setup in
+ * dsl_dir_activate_fs_ss_limit() and the counts are adjusted, if necessary, by
+ * dsl_dir_init_fs_ss_count().
+ *
+ * There is a special case when we receive a filesystem that already exists. In
+ * this case a temporary clone name of %X is created (see dmu_recv_begin). We
+ * never update the filesystem counts for temporary clones.
+ *
+ * Likewise, we do not update the snapshot counts for temporary snapshots,
+ * such as those created by zfs diff.
+ */
 
 static uint64_t dsl_dir_space_towrite(dsl_dir_t *dd);
 
@@ -383,6 +463,402 @@ dsl_dir_hold(dsl_pool_t *dp, const char *name, void *tag,
 	return (err);
 }
 
+/*
+ * If the counts are already initialized for this filesystem and its
+ * descendants then do nothing, otherwise initialize the counts.
+ *
+ * The counts on this filesystem, and those below, may be uninitialized due to
+ * either the use of a pre-existing pool which did not support the
+ * filesystem/snapshot limit feature, or one in which the feature had not yet
+ * been enabled.
+ *
+ * Recursively descend the filesystem tree and update the filesystem/snapshot
+ * counts on each filesystem below, then update the cumulative count on the
+ * current filesystem. If the filesystem already has a count set on it,
+ * then we know that its counts, and the counts on the filesystems below it,
+ * are already correct, so we don't have to update this filesystem.
+ */
+static void
+dsl_dir_init_fs_ss_count(dsl_dir_t *dd, dmu_tx_t *tx)
+{
+	uint64_t my_fs_cnt = 0;
+	uint64_t my_ss_cnt = 0;
+	dsl_pool_t *dp = dd->dd_pool;
+	objset_t *os = dp->dp_meta_objset;
+	zap_cursor_t *zc;
+	zap_attribute_t *za;
+	dsl_dataset_t *ds;
+
+	ASSERT(spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_FS_SS_LIMIT));
+	ASSERT(dsl_pool_config_held(dp));
+	ASSERT(dmu_tx_is_syncing(tx));
+
+	dsl_dir_zapify(dd, tx);
+
+	/*
+	 * If the filesystem count has already been initialized then we
+	 * don't need to recurse down any further.
+	 */
+	if (zap_contains(os, dd->dd_object, DD_FIELD_FILESYSTEM_COUNT) == 0)
+		return;
+
+	zc = kmem_alloc(sizeof (zap_cursor_t), KM_SLEEP);
+	za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
+
+	/* Iterate my child dirs */
+	for (zap_cursor_init(zc, os, dd->dd_phys->dd_child_dir_zapobj);
+	    zap_cursor_retrieve(zc, za) == 0; zap_cursor_advance(zc)) {
+		dsl_dir_t *chld_dd;
+		uint64_t count;
+
+		VERIFY0(dsl_dir_hold_obj(dp, za->za_first_integer, NULL, FTAG,
+		    &chld_dd));
+
+		/*
+		 * Ignore hidden ($FREE, $MOS & $ORIGIN) objsets and
+		 * temporary datasets.
+		 */
+		if (chld_dd->dd_myname[0] == '$' ||
+		    chld_dd->dd_myname[0] == '%') {
+			dsl_dir_rele(chld_dd, FTAG);
+			continue;
+		}
+
+		my_fs_cnt++;	/* count this child */
+
+		dsl_dir_init_fs_ss_count(chld_dd, tx);
+
+		VERIFY0(zap_lookup(os, chld_dd->dd_object,
+		    DD_FIELD_FILESYSTEM_COUNT, sizeof (count), 1, &count));
+		my_fs_cnt += count;
+		VERIFY0(zap_lookup(os, chld_dd->dd_object,
+		    DD_FIELD_SNAPSHOT_COUNT, sizeof (count), 1, &count));
+		my_ss_cnt += count;
+
+		dsl_dir_rele(chld_dd, FTAG);
+	}
+	zap_cursor_fini(zc);
+	/* Count my snapshots (we counted children's snapshots above) */
+	VERIFY0(dsl_dataset_hold_obj(dd->dd_pool,
+	    dd->dd_phys->dd_head_dataset_obj, FTAG, &ds));
+
+	for (zap_cursor_init(zc, os, ds->ds_phys->ds_snapnames_zapobj);
+	    zap_cursor_retrieve(zc, za) == 0;
+	    zap_cursor_advance(zc)) {
+		/* Don't count temporary snapshots */
+		if (za->za_name[0] != '%')
+			my_ss_cnt++;
+	}
+
+	dsl_dataset_rele(ds, FTAG);
+
+	kmem_free(zc, sizeof (zap_cursor_t));
+	kmem_free(za, sizeof (zap_attribute_t));
+
+	/* we're in a sync task, update counts */
+	dmu_buf_will_dirty(dd->dd_dbuf, tx);
+	VERIFY0(zap_add(os, dd->dd_object, DD_FIELD_FILESYSTEM_COUNT,
+	    sizeof (my_fs_cnt), 1, &my_fs_cnt, tx));
+	VERIFY0(zap_add(os, dd->dd_object, DD_FIELD_SNAPSHOT_COUNT,
+	    sizeof (my_ss_cnt), 1, &my_ss_cnt, tx));
+}
+
+static int
+dsl_dir_actv_fs_ss_limit_check(void *arg, dmu_tx_t *tx)
+{
+	char *ddname = (char *)arg;
+	dsl_pool_t *dp = dmu_tx_pool(tx);
+	dsl_dataset_t *ds;
+	dsl_dir_t *dd;
+	int error;
+
+	error = dsl_dataset_hold(dp, ddname, FTAG, &ds);
+	if (error != 0)
+		return (error);
+
+	if (!spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_FS_SS_LIMIT)) {
+		dsl_dataset_rele(ds, FTAG);
+		return (SET_ERROR(ENOTSUP));
+	}
+
+	dd = ds->ds_dir;
+	if (spa_feature_is_active(dp->dp_spa, SPA_FEATURE_FS_SS_LIMIT) &&
+	    dsl_dir_is_zapified(dd) &&
+	    zap_contains(dp->dp_meta_objset, dd->dd_object,
+	    DD_FIELD_FILESYSTEM_COUNT) == 0) {
+		dsl_dataset_rele(ds, FTAG);
+		return (SET_ERROR(EALREADY));
+	}
+
+	dsl_dataset_rele(ds, FTAG);
+	return (0);
+}
+
+static void
+dsl_dir_actv_fs_ss_limit_sync(void *arg, dmu_tx_t *tx)
+{
+	char *ddname = (char *)arg;
+	dsl_pool_t *dp = dmu_tx_pool(tx);
+	dsl_dataset_t *ds;
+	spa_t *spa;
+
+	VERIFY0(dsl_dataset_hold(dp, ddname, FTAG, &ds));
+
+	spa = dsl_dataset_get_spa(ds);
+
+	if (!spa_feature_is_active(spa, SPA_FEATURE_FS_SS_LIMIT)) {
+		/*
+		 * Since the feature was not active and we're now setting a
+		 * limit, increment the feature-active counter so that the
+		 * feature becomes active for the first time.
+		 *
+		 * We are already in a sync task so we can update the MOS.
+		 */
+		spa_feature_incr(spa, SPA_FEATURE_FS_SS_LIMIT, tx);
+	}
+
+	/*
+	 * Since we are now setting a non-UINT64_MAX limit on the filesystem,
+	 * we need to ensure the counts are correct. Descend down the tree from
+	 * this point and update all of the counts to be accurate.
+	 */
+	dsl_dir_init_fs_ss_count(ds->ds_dir, tx);
+
+	dsl_dataset_rele(ds, FTAG);
+}
+
+/*
+ * Make sure the feature is enabled and activate it if necessary.
+ * Since we're setting a limit, ensure the on-disk counts are valid.
+ * This is only called by the ioctl path when setting a limit value.
+ *
+ * We do not need to validate the new limit, since users who can change the
+ * limit are also allowed to exceed the limit.
+ */
+int
+dsl_dir_activate_fs_ss_limit(const char *ddname)
+{
+	int error;
+
+	error = dsl_sync_task(ddname, dsl_dir_actv_fs_ss_limit_check,
+	    dsl_dir_actv_fs_ss_limit_sync, (void *)ddname, 0);
+
+	if (error == EALREADY)
+		error = 0;
+
+	return (error);
+}
+
+/*
+ * Used to determine if the filesystem_limit or snapshot_limit should be
+ * enforced. We allow the limit to be exceeded if the user has permission to
+ * write the property value. We pass in the creds that we got in the open
+ * context since we will always be the GZ root in syncing context. We also have
+ * to handle the case where we are allowed to change the limit on the current
+ * dataset, but there may be another limit in the tree above.
+ *
+ * We can never modify these two properties within a non-global zone. In
+ * addition, the other checks are modeled on zfs_secpolicy_write_perms. We
+ * can't use that function since we are already holding the dp_config_rwlock.
+ * In addition, we already have the dd and dealing with snapshots is simplified
+ * in this code.
+ */
+
+typedef enum {
+	ENFORCE_ALWAYS,
+	ENFORCE_NEVER,
+	ENFORCE_ABOVE
+} enforce_res_t;
+
+static enforce_res_t
+dsl_enforce_ds_ss_limits(dsl_dir_t *dd, zfs_prop_t prop, cred_t *cr)
+{
+	enforce_res_t enforce = ENFORCE_ALWAYS;
+	uint64_t obj;
+	dsl_dataset_t *ds;
+	uint64_t zoned;
+
+	ASSERT(prop == ZFS_PROP_FILESYSTEM_LIMIT ||
+	    prop == ZFS_PROP_SNAPSHOT_LIMIT);
+
+#ifdef _KERNEL
+#ifdef __FreeBSD__
+	if (jailed(cr))
+#else
+	if (crgetzoneid(cr) != GLOBAL_ZONEID)
+#endif
+		return (ENFORCE_ALWAYS);
+
+	if (secpolicy_zfs(cr) == 0)
+		return (ENFORCE_NEVER);
+#endif
+
+	if ((obj = dd->dd_phys->dd_head_dataset_obj) == 0)
+		return (ENFORCE_ALWAYS);
+
+	ASSERT(dsl_pool_config_held(dd->dd_pool));
+
+	if (dsl_dataset_hold_obj(dd->dd_pool, obj, FTAG, &ds) != 0)
+		return (ENFORCE_ALWAYS);
+
+	if (dsl_prop_get_ds(ds, "zoned", 8, 1, &zoned, NULL) || zoned) {
+		/* Only root can access zoned fs's from the GZ */
+		enforce = ENFORCE_ALWAYS;
+	} else {
+		if (dsl_deleg_access_impl(ds, zfs_prop_to_name(prop), cr) == 0)
+			enforce = ENFORCE_ABOVE;
+	}
+
+	dsl_dataset_rele(ds, FTAG);
+	return (enforce);
+}
+
+/*
+ * Check if adding additional child filesystem(s) would exceed any filesystem
+ * limits or adding additional snapshot(s) would exceed any snapshot limits.
+ * The prop argument indicates which limit to check.
+ *
+ * Note that all filesystem limits up to the root (or the highest
+ * initialized) filesystem or the given ancestor must be satisfied.
+ */
+int
+dsl_fs_ss_limit_check(dsl_dir_t *dd, uint64_t delta, zfs_prop_t prop,
+    dsl_dir_t *ancestor, cred_t *cr)
+{
+	objset_t *os = dd->dd_pool->dp_meta_objset;
+	uint64_t limit, count;
+	char *count_prop;
+	enforce_res_t enforce;
+	int err = 0;
+
+	ASSERT(dsl_pool_config_held(dd->dd_pool));
+	ASSERT(prop == ZFS_PROP_FILESYSTEM_LIMIT ||
+	    prop == ZFS_PROP_SNAPSHOT_LIMIT);
+
+	/*
+	 * If we're allowed to change the limit, don't enforce the limit
+	 * e.g. this can happen if a snapshot is taken by an administrative
+	 * user in the global zone (i.e. a recursive snapshot by root).
+	 * However, we must handle the case of delegated permissions where we
+	 * are allowed to change the limit on the current dataset, but there
+	 * is another limit in the tree above.
+	 */
+	enforce = dsl_enforce_ds_ss_limits(dd, prop, cr);
+	if (enforce == ENFORCE_NEVER)
+		return (0);
+
+	/*
+	 * e.g. if renaming a dataset with no snapshots, count adjustment
+	 * is 0.
+	 */
+	if (delta == 0)
+		return (0);
+
+	if (prop == ZFS_PROP_SNAPSHOT_LIMIT) {
+		/*
+		 * We don't enforce the limit for temporary snapshots. This is
+		 * indicated by a NULL cred_t argument.
+		 */
+		if (cr == NULL)
+			return (0);
+
+		count_prop = DD_FIELD_SNAPSHOT_COUNT;
+	} else {
+		count_prop = DD_FIELD_FILESYSTEM_COUNT;
+	}
+
+	/*
+	 * If an ancestor has been provided, stop checking the limit once we
+	 * hit that dir. We need this during rename so that we don't overcount
+	 * the check once we recurse up to the common ancestor.
+	 */
+	if (ancestor == dd)
+		return (0);
+
+	/*
+	 * If we hit an uninitialized node while recursing up the tree, we can
+	 * stop since we know there is no limit here (or above). The counts are
+	 * not valid on this node and we know we won't touch this node's counts.
+	 */
+	if (!dsl_dir_is_zapified(dd) || zap_lookup(os, dd->dd_object,
+	    count_prop, sizeof (count), 1, &count) == ENOENT)
+		return (0);
+
+	err = dsl_prop_get_dd(dd, zfs_prop_to_name(prop), 8, 1, &limit, NULL,
+	    B_FALSE);
+	if (err != 0)
+		return (err);
+
+	/* Is there a limit which we've hit? */
+	if (enforce == ENFORCE_ALWAYS && (count + delta) > limit)
+		return (SET_ERROR(EDQUOT));
+
+	if (dd->dd_parent != NULL)
+		err = dsl_fs_ss_limit_check(dd->dd_parent, delta, prop,
+		    ancestor, cr);
+
+	return (err);
+}
+
+/*
+ * Adjust the filesystem or snapshot count for the specified dsl_dir_t and all
+ * parents. When a new filesystem/snapshot is created, increment the count on
+ * all parents, and when a filesystem/snapshot is destroyed, decrement the
+ * count.
+ */
+void
+dsl_fs_ss_count_adjust(dsl_dir_t *dd, int64_t delta, const char *prop,
+    dmu_tx_t *tx)
+{
+	int err;
+	objset_t *os = dd->dd_pool->dp_meta_objset;
+	uint64_t count;
+
+	ASSERT(dsl_pool_config_held(dd->dd_pool));
+	ASSERT(dmu_tx_is_syncing(tx));
+	ASSERT(strcmp(prop, DD_FIELD_FILESYSTEM_COUNT) == 0 ||
+	    strcmp(prop, DD_FIELD_SNAPSHOT_COUNT) == 0);
+
+	/*
+	 * When we receive an incremental stream into a filesystem that already
+	 * exists, a temporary clone is created.  We don't count this temporary
+	 * clone, whose name begins with a '%'. We also ignore hidden ($FREE,
+	 * $MOS & $ORIGIN) objsets.
+	 */
+	if ((dd->dd_myname[0] == '%' || dd->dd_myname[0] == '$') &&
+	    strcmp(prop, DD_FIELD_FILESYSTEM_COUNT) == 0)
+		return;
+
+	/*
+	 * e.g. if renaming a dataset with no snapshots, count adjustment is 0
+	 */
+	if (delta == 0)
+		return;
+
+	/*
+	 * If we hit an uninitialized node while recursing up the tree, we can
+	 * stop since we know the counts are not valid on this node and we
+	 * know we shouldn't touch this node's counts. An uninitialized count
+	 * on the node indicates that either the feature has not yet been
+	 * activated or there are no limits on this part of the tree.
+	 */
+	if (!dsl_dir_is_zapified(dd) || (err = zap_lookup(os, dd->dd_object,
+	    prop, sizeof (count), 1, &count)) == ENOENT)
+		return;
+	VERIFY0(err);
+
+	count += delta;
+	/* Use a signed verify to make sure we're not neg. */
+	VERIFY3S(count, >=, 0);
+
+	VERIFY0(zap_update(os, dd->dd_object, prop, sizeof (count), 1, &count,
+	    tx));
+
+	/* Roll up this additional count into our ancestors */
+	if (dd->dd_parent != NULL)
+		dsl_fs_ss_count_adjust(dd->dd_parent, delta, prop, tx);
+}
+
 uint64_t
 dsl_dir_create_sync(dsl_pool_t *dp, dsl_dir_t *pds, const char *name,
     dmu_tx_t *tx)
@@ -407,8 +883,12 @@ dsl_dir_create_sync(dsl_pool_t *dp, dsl_dir_t *pds, const char *name,
 	ddphys = dbuf->db_data;
 
 	ddphys->dd_creation_time = gethrestime_sec();
-	if (pds)
+	if (pds) {
 		ddphys->dd_parent_obj = pds->dd_object;
+
+		/* update the filesystem counts */
+		dsl_fs_ss_count_adjust(pds, 1, DD_FIELD_FILESYSTEM_COUNT, tx);
+	}
 	ddphys->dd_props_zapobj = zap_create(mos,
 	    DMU_OT_DSL_PROPS, DMU_OT_NONE, 0, tx);
 	ddphys->dd_child_dir_zapobj = zap_create(mos,
@@ -457,6 +937,22 @@ dsl_dir_stats(dsl_dir_t *dd, nvlist_t *nv)
 	}
 	mutex_exit(&dd->dd_lock);
 
+	if (dsl_dir_is_zapified(dd)) {
+		uint64_t count;
+		objset_t *os = dd->dd_pool->dp_meta_objset;
+
+		if (zap_lookup(os, dd->dd_object, DD_FIELD_FILESYSTEM_COUNT,
+		    sizeof (count), 1, &count) == 0) {
+			dsl_prop_nvlist_add_uint64(nv,
+			    ZFS_PROP_FILESYSTEM_COUNT, count);
+		}
+		if (zap_lookup(os, dd->dd_object, DD_FIELD_SNAPSHOT_COUNT,
+		    sizeof (count), 1, &count) == 0) {
+			dsl_prop_nvlist_add_uint64(nv,
+			    ZFS_PROP_SNAPSHOT_COUNT, count);
+		}
+	}
+
 	if (dsl_dir_is_clone(dd)) {
 		dsl_dataset_t *ds;
 		char buf[MAXNAMELEN];
@@ -1155,6 +1651,7 @@ would_change(dsl_dir_t *dd, int64_t delta, dsl_dir_t *ancestor)
 typedef struct dsl_dir_rename_arg {
 	const char *ddra_oldname;
 	const char *ddra_newname;
+	cred_t *ddra_cred;
 } dsl_dir_rename_arg_t;
 
 /* ARGSUSED */
@@ -1219,10 +1716,50 @@ dsl_dir_rename_check(void *arg, dmu_tx_t *tx)
 		}
 	}
 
+	if (dmu_tx_is_syncing(tx)) {
+		if (spa_feature_is_enabled(dp->dp_spa,
+		    SPA_FEATURE_FS_SS_LIMIT)) {
+			/*
+			 * Although this is the check function and we don't
+			 * normally make on-disk changes in check functions,
+			 * we need to do that here.
+			 *
+			 * Ensure this portion of the tree's counts have been
+			 * initialized in case the new parent has limits set.
+			 */
+			dsl_dir_init_fs_ss_count(dd, tx);
+		}
+	}
+
 	if (newparent != dd->dd_parent) {
 		/* is there enough space? */
 		uint64_t myspace =
 		    MAX(dd->dd_phys->dd_used_bytes, dd->dd_phys->dd_reserved);
+		objset_t *os = dd->dd_pool->dp_meta_objset;
+		uint64_t fs_cnt = 0;
+		uint64_t ss_cnt = 0;
+
+		if (dsl_dir_is_zapified(dd)) {
+			int err;
+
+			err = zap_lookup(os, dd->dd_object,
+			    DD_FIELD_FILESYSTEM_COUNT, sizeof (fs_cnt), 1,
+			    &fs_cnt);
+			if (err != ENOENT && err != 0)
+				return (err);
+
+			/*
+			 * have to add 1 for the filesystem itself that we're
+			 * moving
+			 */
+			fs_cnt++;
+
+			err = zap_lookup(os, dd->dd_object,
+			    DD_FIELD_SNAPSHOT_COUNT, sizeof (ss_cnt), 1,
+			    &ss_cnt);
+			if (err != ENOENT && err != 0)
+				return (err);
+		}
 
 		/* no rename into our descendant */
 		if (closest_common_ancestor(dd, newparent) == dd) {
@@ -1232,7 +1769,7 @@ dsl_dir_rename_check(void *arg, dmu_tx_t *tx)
 		}
 
 		error = dsl_dir_transfer_possible(dd->dd_parent,
-		    newparent, myspace);
+		    newparent, fs_cnt, ss_cnt, myspace, ddra->ddra_cred);
 		if (error != 0) {
 			dsl_dir_rele(newparent, FTAG);
 			dsl_dir_rele(dd, FTAG);
@@ -1264,6 +1801,37 @@ dsl_dir_rename_sync(void *arg, dmu_tx_t *tx)
 	    "-> %s", ddra->ddra_newname);
 
 	if (newparent != dd->dd_parent) {
+		objset_t *os = dd->dd_pool->dp_meta_objset;
+		uint64_t fs_cnt = 0;
+		uint64_t ss_cnt = 0;
+
+		/*
+		 * We already made sure the dd counts were initialized in the
+		 * check function.
+		 */
+		if (spa_feature_is_enabled(dp->dp_spa,
+		    SPA_FEATURE_FS_SS_LIMIT)) {
+			VERIFY0(zap_lookup(os, dd->dd_object,
+			    DD_FIELD_FILESYSTEM_COUNT, sizeof (fs_cnt), 1,
+			    &fs_cnt));
+			/* add 1 for the filesystem itself that we're moving */
+			fs_cnt++;
+
+			VERIFY0(zap_lookup(os, dd->dd_object,
+			    DD_FIELD_SNAPSHOT_COUNT, sizeof (ss_cnt), 1,
+			    &ss_cnt));
+		}
+
+		dsl_fs_ss_count_adjust(dd->dd_parent, -fs_cnt,
+		    DD_FIELD_FILESYSTEM_COUNT, tx);
+		dsl_fs_ss_count_adjust(newparent, fs_cnt,
+		    DD_FIELD_FILESYSTEM_COUNT, tx);
+
+		dsl_fs_ss_count_adjust(dd->dd_parent, -ss_cnt,
+		    DD_FIELD_SNAPSHOT_COUNT, tx);
+		dsl_fs_ss_count_adjust(newparent, ss_cnt,
+		    DD_FIELD_SNAPSHOT_COUNT, tx);
+
 		dsl_dir_diduse_space(dd->dd_parent, DD_USED_CHILD,
 		    -dd->dd_phys->dd_used_bytes,
 		    -dd->dd_phys->dd_compressed_bytes,
@@ -1321,17 +1889,20 @@ dsl_dir_rename(const char *oldname, const char *newname)
 
 	ddra.ddra_oldname = oldname;
 	ddra.ddra_newname = newname;
+	ddra.ddra_cred = CRED();
 
 	return (dsl_sync_task(oldname,
 	    dsl_dir_rename_check, dsl_dir_rename_sync, &ddra, 3));
 }
 
 int
-dsl_dir_transfer_possible(dsl_dir_t *sdd, dsl_dir_t *tdd, uint64_t space)
+dsl_dir_transfer_possible(dsl_dir_t *sdd, dsl_dir_t *tdd,
+    uint64_t fs_cnt, uint64_t ss_cnt, uint64_t space, cred_t *cr)
 {
 	dsl_dir_t *ancestor;
 	int64_t adelta;
 	uint64_t avail;
+	int err;
 
 	ancestor = closest_common_ancestor(sdd, tdd);
 	adelta = would_change(sdd, -space, ancestor);
@@ -1339,6 +1910,15 @@ dsl_dir_transfer_possible(dsl_dir_t *sdd, dsl_dir_t *tdd, uint64_t space)
 	if (avail < space)
 		return (SET_ERROR(ENOSPC));
 
+	err = dsl_fs_ss_limit_check(tdd, fs_cnt, ZFS_PROP_FILESYSTEM_LIMIT,
+	    ancestor, cr);
+	if (err != 0)
+		return (err);
+	err = dsl_fs_ss_limit_check(tdd, ss_cnt, ZFS_PROP_SNAPSHOT_LIMIT,
+	    ancestor, cr);
+	if (err != 0)
+		return (err);
+
 	return (0);
 }
 
@@ -1371,3 +1951,12 @@ dsl_dir_zapify(dsl_dir_t *dd, dmu_tx_t *tx)
 	objset_t *mos = dd->dd_pool->dp_meta_objset;
 	dmu_object_zapify(mos, dd->dd_object, DMU_OT_DSL_DIR, tx);
 }
+
+boolean_t
+dsl_dir_is_zapified(dsl_dir_t *dd)
+{
+	dmu_object_info_t doi;
+
+	dmu_object_info_from_db(dd->dd_dbuf, &doi);
+	return (doi.doi_type == DMU_OTN_ZAP_METADATA);
+}
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_send.h b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_send.h
index 13ef511..2b95b8c 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_send.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_send.h
@@ -23,7 +23,7 @@
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2013 by Delphix. All rights reserved.
  * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
- * Copyright (c) 2012, Joyent, Inc. All rights reserved.
+ * Copyright (c) 2013, Joyent, Inc. All rights reserved.
  */
 
 #ifndef _DMU_SEND_H
@@ -63,6 +63,7 @@ typedef struct dmu_recv_cookie {
 	zio_cksum_t drc_cksum;
 	uint64_t drc_newsnapobj;
 	void *drc_owner;
+	cred_t *drc_cred;
 } dmu_recv_cookie_t;
 
 int dmu_recv_begin(char *tofs, char *tosnap, struct drr_begin *drrb,
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dataset.h b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dataset.h
index 5132ef9..d9552b2 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dataset.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dataset.h
@@ -21,7 +21,7 @@
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2013 by Delphix. All rights reserved.
- * Copyright (c) 2012, Joyent, Inc. All rights reserved.
+ * Copyright (c) 2013, Joyent, Inc. All rights reserved.
  * Copyright (c) 2013 Steven Hartland. All rights reserved.
  */
 
@@ -266,7 +266,7 @@ int dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone,
 void dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone,
     dsl_dataset_t *origin_head, dmu_tx_t *tx);
 int dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname,
-    dmu_tx_t *tx, boolean_t recv);
+    dmu_tx_t *tx, boolean_t recv, uint64_t cnt, cred_t *cr);
 void dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname,
     dmu_tx_t *tx);
 
@@ -276,7 +276,8 @@ void dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds);
 int dsl_dataset_get_snapname(dsl_dataset_t *ds);
 int dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name,
     uint64_t *value);
-int dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx);
+int dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx,
+    boolean_t adj_cnt);
 void dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds,
     zprop_source_t source, uint64_t value, dmu_tx_t *tx);
 void dsl_dataset_zapify(dsl_dataset_t *ds, dmu_tx_t *tx);
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dir.h b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dir.h
index 87e2ce8..752ccad 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dir.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dir.h
@@ -21,6 +21,7 @@
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2013 by Delphix. All rights reserved.
+ * Copyright (c) 2014, Joyent, Inc. All rights reserved.
  */
 
 #ifndef	_SYS_DSL_DIR_H
@@ -38,6 +39,14 @@ extern "C" {
 
 struct dsl_dataset;
 
+/*
+ * DD_FIELD_* are strings that are used in the "extensified" dsl_dir zap object.
+ * They should be of the format <reverse-dns>:<field>.
+ */
+
+#define	DD_FIELD_FILESYSTEM_COUNT	"com.joyent:filesystem_count"
+#define	DD_FIELD_SNAPSHOT_COUNT		"com.joyent:snapshot_count"
+
 typedef enum dd_used {
 	DD_USED_HEAD,
 	DD_USED_SNAP,
@@ -129,8 +138,13 @@ int dsl_dir_set_quota(const char *ddname, zprop_source_t source,
     uint64_t quota);
 int dsl_dir_set_reservation(const char *ddname, zprop_source_t source,
     uint64_t reservation);
+int dsl_dir_activate_fs_ss_limit(const char *);
+int dsl_fs_ss_limit_check(dsl_dir_t *, uint64_t, zfs_prop_t, dsl_dir_t *,
+    cred_t *);
+void dsl_fs_ss_count_adjust(dsl_dir_t *, int64_t, const char *, dmu_tx_t *);
 int dsl_dir_rename(const char *oldname, const char *newname);
-int dsl_dir_transfer_possible(dsl_dir_t *sdd, dsl_dir_t *tdd, uint64_t space);
+int dsl_dir_transfer_possible(dsl_dir_t *sdd, dsl_dir_t *tdd,
+    uint64_t fs_cnt, uint64_t ss_cnt, uint64_t space, cred_t *);
 boolean_t dsl_dir_is_clone(dsl_dir_t *dd);
 void dsl_dir_new_refreservation(dsl_dir_t *dd, struct dsl_dataset *ds,
     uint64_t reservation, cred_t *cr, dmu_tx_t *tx);
@@ -138,6 +152,8 @@ void dsl_dir_snap_cmtime_update(dsl_dir_t *dd);
 timestruc_t dsl_dir_snap_cmtime(dsl_dir_t *dd);
 void dsl_dir_set_reservation_sync_impl(dsl_dir_t *dd, uint64_t value,
     dmu_tx_t *tx);
+void dsl_dir_zapify(dsl_dir_t *dd, dmu_tx_t *tx);
+boolean_t dsl_dir_is_zapified(dsl_dir_t *dd);
 
 /* internal reserved dir name */
 #define	MOS_DIR_NAME "$MOS"
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ioctl.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ioctl.c
index 328bbe9..4f7c082 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ioctl.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ioctl.c
@@ -25,7 +25,7 @@
  * All rights reserved.
  * Copyright 2013 Martin Matuska <mm@FreeBSD.org>. All rights reserved.
  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
- * Copyright (c) 2012, Joyent, Inc. All rights reserved.
+ * Copyright (c) 2014, Joyent, Inc. All rights reserved.
  * Copyright (c) 2013 by Delphix. All rights reserved.
  * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
  * Copyright (c) 2013 Steven Hartland. All rights reserved.
@@ -634,12 +634,14 @@ zfs_secpolicy_setprop(const char *dsname, zfs_prop_t prop, nvpair_t *propval,
 		break;
 
 	case ZFS_PROP_QUOTA:
+	case ZFS_PROP_FILESYSTEM_LIMIT:
+	case ZFS_PROP_SNAPSHOT_LIMIT:
 		if (!INGLOBALZONE(curthread)) {
 			uint64_t zoned;
 			char setpoint[MAXNAMELEN];
 			/*
 			 * Unprivileged users are allowed to modify the
-			 * quota on things *under* (ie. contained by)
+			 * limit on things *under* (ie. contained by)
 			 * the thing they own.
 			 */
 			if (dsl_prop_get_integer(dsname, "jailed", &zoned,
@@ -2457,6 +2459,21 @@ zfs_prop_set_special(const char *dsname, zprop_source_t source,
 	case ZFS_PROP_REFQUOTA:
 		err = dsl_dataset_set_refquota(dsname, source, intval);
 		break;
+	case ZFS_PROP_FILESYSTEM_LIMIT:
+	case ZFS_PROP_SNAPSHOT_LIMIT:
+		if (intval == UINT64_MAX) {
+			/* clearing the limit, just do it */
+			err = 0;
+		} else {
+			err = dsl_dir_activate_fs_ss_limit(dsname);
+		}
+		/*
+		 * Set err to -1 to force the zfs_set_prop_nvlist code down the
+		 * default path to set the value in the nvlist.
+		 */
+		if (err == 0)
+			err = -1;
+		break;
 	case ZFS_PROP_RESERVATION:
 		err = dsl_dir_set_reservation(dsname, source, intval);
 		break;
diff --git a/sys/cddl/contrib/opensolaris/uts/common/sys/fs/zfs.h b/sys/cddl/contrib/opensolaris/uts/common/sys/fs/zfs.h
index e9d7420..87cb82e 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/sys/fs/zfs.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/sys/fs/zfs.h
@@ -23,7 +23,7 @@
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2013 by Delphix. All rights reserved.
  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
- * Copyright (c) 2012, Joyent, Inc. All rights reserved.
+ * Copyright (c) 2013, Joyent, Inc. All rights reserved.
  * Copyright (c) 2012, Martin Matuska <mm@FreeBSD.org>. All rights reserved.
  */
 
@@ -146,6 +146,10 @@ typedef enum {
 	ZFS_PROP_LOGICALREFERENCED,
 	ZFS_PROP_INCONSISTENT,		/* not exposed to the user */
 	ZFS_PROP_VOLMODE,
+	ZFS_PROP_FILESYSTEM_LIMIT,
+	ZFS_PROP_SNAPSHOT_LIMIT,
+	ZFS_PROP_FILESYSTEM_COUNT,
+	ZFS_PROP_SNAPSHOT_COUNT,
 	ZFS_NUM_PROPS
 } zfs_prop_t;