Documentation: add networking driver's mapping error handling to DMA-API-HOWTO

[pandora-kernel.git] / Documentation / DMA-API-HOWTO.txt

diff --git a/Documentation/DMA-API-HOWTO.txt b/Documentation/DMA-API-HOWTO.txt
index 52618ab..93d9087 100644 (file)
--- a/Documentation/DMA-API-HOWTO.txt
+++ b/Documentation/DMA-API-HOWTO.txt
@@ -740,9 +740,14 @@ failure can be determined by:
                 */
        }
 
+Networking drivers must call dev_kfree_skb to free the socket buffer
+and return NETDEV_TX_OK if the DMA mapping fails on the transmit hook
+(ndo_start_xmit). This means that the socket buffer is just dropped in
+the failure case.
+
                           Closing
 
-This document, and the API itself, would not be in it's current
+This document, and the API itself, would not be in its current
 form without the feedback and suggestions from numerous individuals.
 We would like to specifically mention, in no particular order, the
 following people: