If the buffer_id of a message received by a controller is -1 (0xffffffff) then no buffer is used by that message. In this case the controller may allocate a buffer for use by resulting packet_in messages unless the max_len of output action that causes the packet_in message is OFPCML_NO_BUFFER (0xffff).
If a buffer is allocated by the controller then the buffer_id of packet_in messages will have a value other than -1. Conversely if no buffer is used in a packet_in message that results from a message received by a controller, because none was specified in the message received (its buffer_id was -1) and either max_len of the output action is OFPCML_NO_BUFFER or the controller does not to allocate a buffer for any other reason then the value of the buffer_id in packet_in messages will be -1. Thus, in the case that buffer_id is -1 in a packet_out message setting max_len of output actions to OFPCML_NO_BUFFER will ensure the packet_in messages with buffer_id -1. That is the buffer_id of the packet_out and packet_in messages will match. Another approach would be to not verify the buffer_id if it is -1. But it seems more thorough to exercise the OFPCML_NO_BUFFER behaviour of the controller. I noticed this when using Open vSwitch's "make ryu-check" as Open vSwitch allocates buffers if OFPCML_NO_BUFFER is not in effect. This appears to be compliant with section A.2.5 the OpenFlow 1.2 spec. Signed-off-by: Simon Horman <[email protected]> --- v2 * Correct spelling errors ryu/tests/integrated/test_request_reply_v12.py | 35 ++++++++++++++++++++++++-- 1 file changed, 33 insertions(+), 2 deletions(-) diff --git a/ryu/tests/integrated/test_request_reply_v12.py b/ryu/tests/integrated/test_request_reply_v12.py index b60a2ba..eb76028 100644 --- a/ryu/tests/integrated/test_request_reply_v12.py +++ b/ryu/tests/integrated/test_request_reply_v12.py @@ -916,6 +916,35 @@ class RunTest(tester.TestFlowBase): def verify_flow_removed_table_id(self, dp, msg): return self._verify_flow_removed(dp, msg) + def _max_len(self, dp, len_, buffer_id=0xffffffff): + if buffer_id == 0xffffffff: + # If the buffer_id of a message received by a controller is + # -1 (0xffffffff) then no buffer is used by that message. + # In this case the controller may allocate a buffer for use by + # resulting packet_in messages unless the max_len of output + # action that causes the packet_in message is OFPCML_NO_BUFFER + # (0xffff). + # + # If a buffer is allocated by the controller then the buffer_id + # of packet_in messages will have a value other than -1. + # + # Conversely if no buffer is used in a packet_in message that + # results from a message received by a controller, because none + # was specified in the message received (its buffer_id was -1) + # and either max_len of the output action is OFPCML_NO_BUFFER + # or the controller does not to allocate a buffer for any other + # reason then the value of the buffer_id in packet_in messages + # will be -1. + # + # Thus, in the case that buffer_id is -1 in a packet_out + # message setting max_len of output actions to OFPCML_NO_BUFFER + # will ensure the packet_in messages with buffer_id -1. That + # is the buffer_id of the packet_out and packet_in messages + # will match. + return dp.ofproto.OFPCML_NO_BUFFER + else: + return len_ + def _send_packet_out(self, dp, buffer_id=0xffffffff, in_port=None, output=None, data=''): if in_port is None: @@ -928,7 +957,8 @@ class RunTest(tester.TestFlowBase): self._verify['in_port'] = in_port self._verify['data'] = data - actions = [dp.ofproto_parser.OFPActionOutput(output, len(data))] + max_len = self._max_len(dp, len(data), buffer_id) + actions = [dp.ofproto_parser.OFPActionOutput(output, max_len)] m = dp.ofproto_parser.OFPPacketOut(dp, buffer_id, in_port, actions, data) dp.send_msg(m) @@ -983,7 +1013,8 @@ class RunTest(tester.TestFlowBase): match = dp.ofproto_parser.OFPMatch() match.set_in_port(in_port) out = dp.ofproto.OFPP_CONTROLLER - actions = [dp.ofproto_parser.OFPActionOutput(out, 0)] + max_len = self._max_len(dp, 0) + actions = [dp.ofproto_parser.OFPActionOutput(out, max_len)] self.mod_flow(dp, actions=actions, match=match, table_id=table_id) dp.send_barrier() -- 1.8.5.2 ------------------------------------------------------------------------------ Start Your Social Network Today - Download eXo Platform Build your Enterprise Intranet with eXo Platform Software Java Based Open Source Intranet - Social, Extensible, Cloud Ready Get Started Now And Turn Your Intranet Into A Collaboration Platform http://p.sf.net/sfu/ExoPlatform _______________________________________________ Ryu-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/ryu-devel
