[openib-general] [PATCH 2 of 2] mad: check GID/LID when searching for request

[Michael S. Tsirkin]

Check GID/LID for requester side when searching for request which matches
received response.  This, in order to guarantee uniqueness if use same TID
when requesting via multiple source LIDs (when LMC is not zero).
To perform check, use LMC to cache.

Further, do not perform LID check for direct-routed packets, since permissive
LID makes a proper check impossible.

Signed-off-by: Jack Morgenstein <jackm at mellanox.co.il>

Index: src/drivers/infiniband/core/mad.c
===================================================================
--- src/drivers/infiniband/core/mad.c	(revision 6066)
+++ src/drivers/infiniband/core/mad.c	(working copy)
@@ -34,6 +34,7 @@
  * $Id$
  */
 #include <linux/dma-mapping.h>
+#include <rdma/ib_cache.h>
 
 #include "mad_priv.h"
 #include "mad_rmpp.h"
@@ -1669,20 +1670,21 @@ static inline int rcv_has_same_class(str
 		rwc->recv_buf.mad->mad_hdr.mgmt_class;
 }
 
-static inline int rcv_has_same_gid(struct ib_mad_send_wr_private *wr,
+static inline int rcv_has_same_gid(struct ib_mad_agent_private 
*mad_agent_priv,
+				   struct ib_mad_send_wr_private *wr,
 				   struct ib_mad_recv_wc *rwc )
 {
 	struct ib_ah_attr attr;
 	u8 send_resp, rcv_resp;
+	union ib_gid sgid;
+	struct ib_device *device = mad_agent_priv->agent.device;
+	u8 port_num = mad_agent_priv->agent.port_num;
+	u8 lmc;
 
 	send_resp = ((struct ib_mad *)(wr->send_buf.mad))->
 		     mad_hdr.method & IB_MGMT_METHOD_RESP;
 	rcv_resp = rwc->recv_buf.mad->mad_hdr.method & IB_MGMT_METHOD_RESP;
 
-	if (!send_resp && rcv_resp)
-		/* is request/response. GID/LIDs are both local (same). */
-		return 1;
-
 	if (send_resp == rcv_resp)
 		/* both requests, or both responses. GIDs different */
 		return 0;
@@ -1691,48 +1693,78 @@ static inline int rcv_has_same_gid(struc
 		/* Assume not equal, to avoid false positives. */
 		return 0;
 
-	if (!(attr.ah_flags & IB_AH_GRH) && !(rwc->wc->wc_flags & IB_WC_GRH))
-		return attr.dlid == rwc->wc->slid;
-	else if ((attr.ah_flags & IB_AH_GRH) &&
-		 (rwc->wc->wc_flags & IB_WC_GRH))
-		return memcmp(attr.grh.dgid.raw,
-			      rwc->recv_buf.grh->sgid.raw, 16) == 0;
-	else
+	if (!!(attr.ah_flags & IB_AH_GRH) !=
+	    !!(rwc->wc->wc_flags & IB_WC_GRH))
 		/* one has GID, other does not.  Assume different */
 		return 0;
+
+	if (!send_resp && rcv_resp) {
+		/* is request/response. */
+		if (!(attr.ah_flags & IB_AH_GRH)) {
+			if (ib_get_cached_lmc(device, port_num, &lmc))
+				return 0;
+			return (!lmc || !((attr.src_path_bits ^
+					   rwc->wc->dlid_path_bits) &
+					  ((1 << lmc) - 1)));
+		} else {
+			if (ib_get_cached_gid(device, port_num,
+					      attr.grh.sgid_index, &sgid))
+				return 0;
+			return !memcmp(sgid.raw, rwc->recv_buf.grh->dgid.raw,
+				       16);
+		}
+	}
+
+	if (!(attr.ah_flags & IB_AH_GRH))
+		return attr.dlid == rwc->wc->slid;
+	else
+		return !memcmp(attr.grh.dgid.raw, rwc->recv_buf.grh->sgid.raw,
+			       16);
 }
+
+static inline int is_direct(u8 class)
+{
+	return (class == IB_MGMT_CLASS_SUBN_DIRECTED_ROUTE);
+}
+
 struct ib_mad_send_wr_private*
 ib_find_send_mad(struct ib_mad_agent_private *mad_agent_priv,
-		 struct ib_mad_recv_wc *mad_recv_wc)
+		 struct ib_mad_recv_wc *wc)
 {
-	struct ib_mad_send_wr_private *mad_send_wr;
+	struct ib_mad_send_wr_private *wr;
 	struct ib_mad *mad;
 
-	mad = (struct ib_mad *)mad_recv_wc->recv_buf.mad;
+	mad = (struct ib_mad *)wc->recv_buf.mad;
 
-	list_for_each_entry(mad_send_wr, &mad_agent_priv->wait_list,
-			    agent_list) {
-		if ((mad_send_wr->tid == mad->mad_hdr.tid) &&
-		    rcv_has_same_class(mad_send_wr, mad_recv_wc) &&
-		    rcv_has_same_gid(mad_send_wr, mad_recv_wc))
-			return mad_send_wr;
+	list_for_each_entry(wr, &mad_agent_priv->wait_list, agent_list) {
+		if ((wr->tid == mad->mad_hdr.tid) &&
+		    rcv_has_same_class(wr, wc) &&
+		    /*
+		     * Don't check GID for direct routed MADs.
+		     * These might have permissive LIDs.
+		     */
+		    (is_direct(wc->recv_buf.mad->mad_hdr.mgmt_class) ||
+		     rcv_has_same_gid(mad_agent_priv, wr, wc)))
+			return wr;
 	}
 
 	/*
 	 * It's possible to receive the response before we've
 	 * been notified that the send has completed
 	 */
-	list_for_each_entry(mad_send_wr, &mad_agent_priv->send_list,
-			    agent_list) {
-		if (is_data_mad(mad_agent_priv, mad_send_wr->send_buf.mad) &&
-		    mad_send_wr->tid == mad->mad_hdr.tid &&
-		    mad_send_wr->timeout &&
-		    rcv_has_same_class(mad_send_wr, mad_recv_wc) &&
-		    rcv_has_same_gid(mad_send_wr, mad_recv_wc)) {
+	list_for_each_entry(wr, &mad_agent_priv->send_list, agent_list) {
+		if (is_data_mad(mad_agent_priv, wr->send_buf.mad) &&
+		    wr->tid == mad->mad_hdr.tid &&
+		    wr->timeout &&
+		    rcv_has_same_class(wr, wc) &&
+		    /*
+		     * Don't check GID for direct routed MADs.
+		     * These might have permissive LIDs.
+		     */
+		    (is_direct(wc->recv_buf.mad->mad_hdr.mgmt_class) ||
+		     rcv_has_same_gid(mad_agent_priv, wr, wc)))
 			/* Verify request has not been canceled */
-			return (mad_send_wr->status == IB_WC_SUCCESS) ?
-				mad_send_wr : NULL;
-		}
+			return (wr->status == IB_WC_SUCCESS) ? wr : NULL;
 	}
 	return NULL;
 }
_______________________________________________
openib-general mailing list
openib-general at openib.org
http://openib.org/mailman/listinfo/openib-general

To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general

-- 
MST