Increase ip_pool to 256 characters

The length of the ip_pool parameter in L3 policies is limited,
and needs to be increased in order to support multiple prefixes,
as well as prefixes from all address families (v4 and v6).

Change-Id: I9dc03ac4275e0f269746011a075bf3b78e0d5233

gbpservice/neutron/db/grouppolicy/group_policy_db.py

@@ -157,7 +157,7 @@ class L3Policy(model_base.BASEV2, BaseSharedGbpResource):
         'polymorphic_identity': 'base'
     }
     ip_version = sa.Column(sa.Integer, nullable=False)
-    ip_pool = sa.Column(sa.String(64))
+    ip_pool = sa.Column(sa.String(255))
     subnet_prefix_length = sa.Column(sa.Integer)
     l2_policies = orm.relationship(L2Policy, backref='l3_policy')
     external_segments = orm.relationship(

gbpservice/neutron/db/migration/alembic_migrations/versions/27b724002081_l3p_ip_pool_size.py

@@ -0,0 +1,39 @@
+# Copyright 2017 OpenStack Foundation
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+#
+
+"""l3p ip pool size
+
+Revision ID: 27b724002081
+Revises: bff1774e749e
+Create Date: 2017-07-06 17:34:18.856803
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '27b724002081'
+down_revision = 'bff1774e749e'
+
+from alembic import op
+import sqlalchemy as sa
+
+
+def upgrade():
+    op.alter_column('gp_l3_policies', 'ip_pool',
+                    existing_type=sa.String(length=64),
+                    type_=sa.String(length=255))
+
+
+def downgrade():
+    pass

gbpservice/neutron/db/migration/alembic_migrations/versions/HEAD

@@ -1 +1 @@
-bff1774e749e
+27b724002081