IB: Set GIDs correctly in ib_create_ah_from_wc()

ib_create_ah_from_wc() doesn't create the correct return address (AH)
when there is a GRH present (source & dest GIDs need to be swapped).

Signed-off-by: Ralph Campbell <ralphc@pathscale.com>
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/infiniband/core/verbs.c

@@ -107,9 +107,9 @@ struct ib_ah *ib_create_ah_from_wc(struct ib_pd *pd, struct ib_wc *wc,
 
 	if (wc->wc_flags & IB_WC_GRH) {
 		ah_attr.ah_flags = IB_AH_GRH;
-		ah_attr.grh.dgid = grh->dgid;
+		ah_attr.grh.dgid = grh->sgid;
 
-		ret = ib_find_cached_gid(pd->device, &grh->sgid, &port_num,
+		ret = ib_find_cached_gid(pd->device, &grh->dgid, &port_num,
 					 &gid_index);
 		if (ret)
 			return ERR_PTR(ret);