From f671be04dcda09f8383ae26072c0e75a79090193 Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Date: Wed, 26 May 2010 14:44:19 -0700 Subject: [PATCH] Documentation: add networking driver's mapping error handling to DMA-API-HOWTO Adds the concrete DMA mapping error handling for Networking drivers on the transmit path. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> --- Documentation/DMA-API-HOWTO.txt | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/Documentation/DMA-API-HOWTO.txt b/Documentation/DMA-API-HOWTO.txt index 2e435adfbd6bb..93d90870791ce 100644 --- a/Documentation/DMA-API-HOWTO.txt +++ b/Documentation/DMA-API-HOWTO.txt @@ -740,6 +740,11 @@ 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 its current -- GitLab