[illumos-gate merge]

commit 5ff8cfa
    5410 Document -S option to zfs inherit
    5412 Mention -S option when zfs inherit fails on quota
commit bc9014e
    5056 ZFS deadlock on db_mtx and dn_holds

usr/src/cmd/zfs/zfs_main.c

@@ -1957,9 +1957,13 @@ zfs_do_inherit(int argc, char **argv)
 			if (prop == ZFS_PROP_QUOTA ||
 			    prop == ZFS_PROP_RESERVATION ||
 			    prop == ZFS_PROP_REFQUOTA ||
-			    prop == ZFS_PROP_REFRESERVATION)
+			    prop == ZFS_PROP_REFRESERVATION) {
 				(void) fprintf(stderr, gettext("use 'zfs set "
 				    "%s=none' to clear\n"), propname);
+				(void) fprintf(stderr, gettext("use 'zfs "
+				    "inherit -S %s' to revert to received "
+				    "value\n"), propname);
+			}
 			return (1);
 		}
 		if (received && (prop == ZFS_PROP_VOLSIZE ||

usr/src/man/man1m/zfs.1m

@@ -119,7 +119,7 @@ zfs \- configures ZFS file systems
 
 .LP
 .nf
-\fBzfs\fR \fBinherit\fR [\fB-r\fR] \fIproperty\fR \fIfilesystem\fR|\fIvolume|snapshot\fR...
+\fBzfs\fR \fBinherit\fR [\fB-rS\fR] \fIproperty\fR \fIfilesystem\fR|\fIvolume|snapshot\fR...
 .fi
 
 .LP
@@ -2429,7 +2429,7 @@ property, the following columns are displayed:
      property  Property name
      value     Property value
      source    Property source. Can either be local, default,
-               temporary, inherited, or none (-).
+               temporary, inherited, received, or none (-).
 .fi
 .in -2
 .sp
@@ -2494,8 +2494,8 @@ is the default value.
 .RS 4n
 A comma-separated list of sources to display. Those properties coming from a
 source other than those in this list are ignored. Each source must be one of
-the following: \fBlocal,default,inherited,temporary,none\fR. The default value
-is all sources.
+the following: \fBlocal,default,inherited,received,temporary,none\fR. The
+default value is all sources.
 .RE
 
 .sp
@@ -2526,15 +2526,16 @@ volume's size and block size.
 .sp
 .ne 2
 .na
-\fB\fBzfs inherit\fR [\fB-r\fR] \fIproperty\fR
+\fB\fBzfs inherit\fR [\fB-rS\fR] \fIproperty\fR
 \fIfilesystem\fR|\fIvolume\fR|\fIsnapshot\fR...\fR
 .ad
 .sp .6
 .RS 4n
-Clears the specified property, causing it to be inherited from an ancestor. If
-no ancestor has the property set, then the default value is used. See the
-"Properties" section for a listing of default values, and details on which
-properties can be inherited.
+Clears the specified property, causing it to be inherited from an ancestor,
+restored to default if no ancestor has the property set, or with the \fB-S\fR
+option reverted to the received value if one exists.  See the "Properties"
+section for a listing of default values, and details on which properties can be
+inherited.
 .sp
 .ne 2
 .na
@@ -2544,6 +2545,16 @@ properties can be inherited.
 .RS 4n
 Recursively inherit the given property for all children.
 .RE
+.sp
+.ne 2
+.na
+\fB\fB-S\fR\fR
+.ad
+.sp .6
+.RS 4n
+Revert the property to the received value if one exists; otherwise operate as
+if the \fB-S\fR option was not specified.
+.RE
 
 .RE
 
@@ -3931,6 +3942,17 @@ inherit the \fBchecksum\fR property from their parent.
 .fi
 .in -2
 .sp
+.LP
+The following command causes \fBpool/home/bob\fR to revert to the received
+value for the \fBquota\fR property if it exists.
+
+.sp
+.in +2
+.nf
+# \fBzfs inherit -S quota pool/home/bob
+.fi
+.in -2
+.sp
 
 .LP
 \fBExample 12 \fRRemotely Replicating ZFS Data