[openib-general] [PATCH] ib_mad.c: Fix request/response matching

Tue Oct 5 13:34:39 PDT 2004

>Fix endian of high tid so responses are properly matched to requests

noooooooooooooooooooo.... the TID is in the MAD and goes on the wire.
Please, do not use CPU endian!

>                 mad_send_wr->tid = ((struct ib_mad_hdr*)
>-
bus_to_virt(cur_send_wr->sg_list->addr))->tid;
>+                                   bus_to_virt(cur_send_wr->sg_list->addr))-
>>tid.id;

A response MAD should have exactly the same TID as what was sent.  Not sure
why we aren't matching against the entire TID.

>         if (solicited) {
>             /* Routing is based on high 32 bits of transaction ID of MAD
>*/
>-            hi_tid = mad->mad_hdr.tid >> 32;
>+            hi_tid = be32_to_cpu(mad->mad_hdr.tid.tid_field.hi_tid);

This shouldn't be necessary:

Sender of request (system 1):
mad.tid = (mad_agent.hi_tid << 32) | user_tid;
send mad

Receiver of response (system 1):
hi_tid = mad.tid >> 32

The receiver of the request should just return the same TID that it
received.

>+        /*
>+     * Leave sends with timeouts on the send list
>+     * until either matching response is received
>+     * or timeout occurs
>+     */

FYI - this is about to change in my next patch.

>+union ib_tid {
>+    u64     id;
>+    struct {
>+            u32     hi_tid;
>+            u32     lo_tid;
>+    } tid_field;
>+};
>+

I don't see why TID can't be u64 everywhere.  We shouldn't have to make it a
union.