RDMA/core: Add iWARP protocol statistics attributes in sysfs

This patch adds a sysfs attribute group called "proto_stats" under
/sys/class/infiniband/$device/ and populates this group with protocol
statistics if they exist for a given device.  Currently, only iWARP
stats are defined, but the code is designed to allow InfiniBand
protocol stats if they become available.  These stats are per-device
and more importantly -not- per port.

Details:

- Add union rdma_protocol_stats in ib_verbs.h.  This union allows
  defining transport-specific stats.  Currently only iwarp stats are
  defined.

- Add struct iw_protocol_stats to define the current set of iwarp
  protocol stats.

- Add new ib_device method called get_proto_stats() to return protocol
  statistics.

- Add logic in core/sysfs.c to create iwarp protocol stats attributes
  if the device is an RNIC and has a get_proto_stats() method.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

include/rdma/ib_verbs.h

@@ -226,6 +226,57 @@ static inline int ib_width_enum_to_int(enum ib_port_width width)
 	}
 }
 
+struct ib_protocol_stats {
+	/* TBD... */
+};
+
+struct iw_protocol_stats {
+	u64	ipInReceives;
+	u64	ipInHdrErrors;
+	u64	ipInTooBigErrors;
+	u64	ipInNoRoutes;
+	u64	ipInAddrErrors;
+	u64	ipInUnknownProtos;
+	u64	ipInTruncatedPkts;
+	u64	ipInDiscards;
+	u64	ipInDelivers;
+	u64	ipOutForwDatagrams;
+	u64	ipOutRequests;
+	u64	ipOutDiscards;
+	u64	ipOutNoRoutes;
+	u64	ipReasmTimeout;
+	u64	ipReasmReqds;
+	u64	ipReasmOKs;
+	u64	ipReasmFails;
+	u64	ipFragOKs;
+	u64	ipFragFails;
+	u64	ipFragCreates;
+	u64	ipInMcastPkts;
+	u64	ipOutMcastPkts;
+	u64	ipInBcastPkts;
+	u64	ipOutBcastPkts;
+
+	u64	tcpRtoAlgorithm;
+	u64	tcpRtoMin;
+	u64	tcpRtoMax;
+	u64	tcpMaxConn;
+	u64	tcpActiveOpens;
+	u64	tcpPassiveOpens;
+	u64	tcpAttemptFails;
+	u64	tcpEstabResets;
+	u64	tcpCurrEstab;
+	u64	tcpInSegs;
+	u64	tcpOutSegs;
+	u64	tcpRetransSegs;
+	u64	tcpInErrs;
+	u64	tcpOutRsts;
+};
+
+union rdma_protocol_stats {
+	struct ib_protocol_stats	ib;
+	struct iw_protocol_stats	iw;
+};
+
 struct ib_port_attr {
 	enum ib_port_state	state;
 	enum ib_mtu		max_mtu;
@@ -943,6 +994,8 @@ struct ib_device {
 
 	struct iw_cm_verbs	     *iwcm;
 
+	int		           (*get_protocol_stats)(struct ib_device *device,
+							 union rdma_protocol_stats *stats);
 	int		           (*query_device)(struct ib_device *device,
 						   struct ib_device_attr *device_attr);
 	int		           (*query_port)(struct ib_device *device,