5410 Document -S option to zfs inherit

5410 Document -S option to zfs inherit
5412 Mention -S option when zfs inherit fails on quota
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Richard Lowe <richlowe@richlowe.net>

References:
  https://www.illumos.org/issues/5410
  https://github.com/illumos/illumos-gate/commit/5ff8cfa9

Ported-by: DHE <git@dehacked.net>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3279

cmd/zfs/zfs_main.c

@@ -1903,9 +1903,13 @@ 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 ||

man/man8/zfs.8

@@ -117,7 +117,7 @@ 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
@@ -2128,7 +2128,7 @@ Displays properties for the given datasets. If no datasets are specified, then t
      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
@@ -2188,7 +2188,7 @@ A comma-separated list of columns to display. \fBname,property,value,source\fR i
 .ad
 .sp .6
 .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.
+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,received,temporary,none\fR. The default value is all sources.
 .RE
 
 .sp
@@ -2208,11 +2208,11 @@ Display numbers in parsable (exact) values.
 .ne 2
 .mk
 .na
-\fB\fBzfs inherit\fR [\fB-r\fR] \fIproperty\fR \fIfilesystem\fR|\fIvolume\fR|\fIsnapshot\fR ...\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
 .mk
@@ -2223,6 +2223,16 @@ Clears the specified property, causing it to be inherited from an ancestor. If n
 .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
 
@@ -3485,6 +3495,17 @@ The following command causes \fBpool/home/bob\fR and \fBpool/home/anne\fR to inh
 .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