Allow zfs unshare <protocol> -a

Allow `zfs unshare <protocol> -a` command to share or unshare all datasets
of a given protocol, nfs or smb.

Additionally, enable most of ZFS Test Suite zfs_share/zfs_unshare test cases.
To work around some Illumos-specific functionalities ($SHARE/$UNSHARE) some
function wrappers were added around them.

Finally, fix and issue in smb_is_share_active() that would leave SMB shares
exported when invoking 'zfs unshare -a'

Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Closes #3238 
Closes #5367

tests/zfs-tests/include/commands.cfg.in

@@ -67,6 +67,7 @@ export MOUNT="@MOUNT@"
 export MPSTAT="@MPSTAT@"
 export MV="@MV@"
 export NAWK="@AWK@"
+export NET="@NET@"
 export NEWFS="@NEWFS@"
 export NPROC="@NPROC@"
 export PAGESIZE="@PAGESIZE@"

tests/zfs-tests/include/libtest.shlib

@@ -1052,7 +1052,7 @@ function datasetnonexists
 }
 
 #
-# Given a mountpoint, or a dataset name, determine if it is shared.
+# Given a mountpoint, or a dataset name, determine if it is shared via NFS.
 #
 # Returns 0 if shared, 1 otherwise.
 #
@@ -1061,11 +1061,6 @@ function is_shared
 	typeset fs=$1
 	typeset mtpt
 
-	if is_linux; then
-		log_unsupported "Currently unsupported by the test framework"
-		return 1
-	fi
-
 	if [[ $fs != "/"* ]] ; then
 		if datasetnonexists "$fs" ; then
 			return 1
@@ -1080,6 +1075,15 @@ function is_shared
 		fi
 	fi
 
+	if is_linux; then
+		for mtpt in `$SHARE | $AWK '{print $1}'` ; do
+			if [[ $mtpt == $fs ]] ; then
+				return 0
+			fi
+		done
+		return 1
+	fi
+
 	for mtpt in `$SHARE | $AWK '{print $2}'` ; do
 		if [[ $mtpt == $fs ]] ; then
 			return 0
@@ -1095,7 +1099,36 @@ function is_shared
 }
 
 #
-# Given a mountpoint, determine if it is not shared.
+# Given a dataset name determine if it is shared via SMB.
+#
+# Returns 0 if shared, 1 otherwise.
+#
+function is_shared_smb
+{
+	typeset fs=$1
+	typeset mtpt
+
+	if datasetnonexists "$fs" ; then
+		return 1
+	else
+		fs=$(echo $fs | sed 's@/@_@g')
+	fi
+
+	if is_linux; then
+		for mtpt in `$NET usershare list | $AWK '{print $1}'` ; do
+			if [[ $mtpt == $fs ]] ; then
+				return 0
+			fi
+		done
+		return 1
+	else
+		log_unsupported "Currently unsupported by the test framework"
+		return 1
+	fi
+}
+
+#
+# Given a mountpoint, determine if it is not shared via NFS.
 #
 # Returns 0 if not shared, 1 otherwise.
 #
@@ -1103,12 +1136,24 @@ function not_shared
 {
 	typeset fs=$1
 
-	if is_linux; then
-		log_unsupported "Currently unsupported by the test framework"
+	is_shared $fs
+	if (($? == 0)); then
 		return 1
 	fi
 
-	is_shared $fs
+	return 0
+}
+
+#
+# Given a dataset determine if it is not shared via SMB.
+#
+# Returns 0 if not shared, 1 otherwise.
+#
+function not_shared_smb
+{
+	typeset fs=$1
+
+	is_shared_smb $fs
 	if (($? == 0)); then
 		return 1
 	fi
@@ -1123,12 +1168,7 @@ function unshare_fs #fs
 {
 	typeset fs=$1
 
-	if is_linux; then
-		log_unsupported "Currently unsupported by the test framework"
-		return 1
-	fi
-
-	is_shared $fs
+	is_shared $fs || is_shared_smb $fs
 	if (($? == 0)); then
 		log_must $ZFS unshare $fs
 	fi
@@ -1136,6 +1176,78 @@ function unshare_fs #fs
 	return 0
 }
 
+#
+# Helper function to share a NFS mountpoint.
+#
+function share_nfs #fs
+{
+	typeset fs=$1
+
+	if is_linux; then
+		is_shared $fs
+		if (($? != 0)); then
+			log_must $SHARE "*:$fs"
+		fi
+	else
+		is_shared $fs
+		if (($? != 0)); then
+			log_must $SHARE -F nfs $fs
+		fi
+	fi
+
+	return 0
+}
+
+#
+# Helper function to unshare a NFS mountpoint.
+#
+function unshare_nfs #fs
+{
+	typeset fs=$1
+
+	if is_linux; then
+		is_shared $fs
+		if (($? == 0)); then
+			log_must $UNSHARE -u "*:$fs"
+		fi
+	else
+		is_shared $fs
+		if (($? == 0)); then
+			log_must $UNSHARE -F nfs $fs
+		fi
+	fi
+
+	return 0
+}
+
+#
+# Helper function to show NFS shares.
+#
+function showshares_nfs
+{
+	if is_linux; then
+		$SHARE -v
+	else
+		$SHARE -F nfs
+	fi
+
+	return 0
+}
+
+#
+# Helper function to show SMB shares.
+#
+function showshares_smb
+{
+	if is_linux; then
+		$NET usershare list
+	else
+		$SHARE -F smb
+	fi
+
+	return 0
+}
+
 #
 # Check NFS server status and trigger it online.
 #
@@ -1149,7 +1261,7 @@ function setup_nfs_server
 	fi
 
 	if is_linux; then
-		log_unsupported "Currently unsupported by the test framework"
+		log_note "NFS server must started prior to running test framework."
 		return
 	fi