From: Hal Rosenstock <halr@voltaire.com>
Date: Wed, 25 Apr 2007 04:30:38 +0000 (-0700)
Subject: IB/umad: Clarify documentation of transaction ID
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=bd8031b49a9b05933fb1ec1c36620ed4e1e67793;p=linux-beck.git

IB/umad: Clarify documentation of transaction ID

Signed-off-by: Hal Rosenstock <halr@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
---

diff --git a/Documentation/infiniband/user_mad.txt b/Documentation/infiniband/user_mad.txt
index 750fe5e80ebc..8ec54b974b67 100644
--- a/Documentation/infiniband/user_mad.txt
+++ b/Documentation/infiniband/user_mad.txt
@@ -91,6 +91,14 @@ Sending MADs
 	if (ret != sizeof *mad + mad_length)
 		perror("write");
 
+Transaction IDs
+
+  Users of the umad devices can use the lower 32 bits of the
+  transaction ID field (that is, the least significant half of the
+  field in network byte order) in MADs being sent to match
+  request/response pairs.  The upper 32 bits are reserved for use by
+  the kernel and will be overwritten before a MAD is sent.
+
 Setting IsSM Capability Bit
 
   To set the IsSM capability bit for a port, simply open the