From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932391Ab1EFAr1 (ORCPT ); Thu, 5 May 2011 20:47:27 -0400 Received: from kroah.org ([198.145.64.141]:37028 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932325Ab1EFAZ0 (ORCPT ); Thu, 5 May 2011 20:25:26 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Thu May 5 17:22:14 2011 Message-Id: <20110506002214.036157708@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Thu, 05 May 2011 17:21:15 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Gertjan van Wingerde , Ivo van Doorn , "John W. Linville" Subject: [090/143] rt2x00: Properly request tx headroom for alignment operations. In-Reply-To: <20110506002311.GA15354@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-longterm review patch. If anyone has any objections, please let us know. ------------------ From: Gertjan van Wingerde commit 7a4a77b7771164d61ce702a588067d1e1d66db7c upstream. Current rt2x00 drivers may result in a "ieee80211_tx_status: headroom too small" error message when a frame needs to be properly aligned before transmitting it. This is because the space needed to ensure proper alignment isn't requested from mac80211. Fix this by adding sufficient amount of alignment space to the amount of headroom requested for TX frames. Reported-by: David Ellingsworth Signed-off-by: Gertjan van Wingerde Acked-by: Ivo van Doorn Signed-off-by: John W. Linville Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/rt2x00/rt2x00.h | 6 ++++++ drivers/net/wireless/rt2x00/rt2x00dev.c | 12 +++++++++++- 2 files changed, 17 insertions(+), 1 deletion(-) --- a/drivers/net/wireless/rt2x00/rt2x00.h +++ b/drivers/net/wireless/rt2x00/rt2x00.h @@ -112,6 +112,12 @@ ( ((unsigned long)((__skb)->data + (__header))) & 3 ) /* + * Constants for extra TX headroom for alignment purposes. + */ +#define RT2X00_ALIGN_SIZE 4 /* Only whole frame needs alignment */ +#define RT2X00_L2PAD_SIZE 8 /* Both header & payload need alignment */ + +/* * Standard timing and size defines. * These values should follow the ieee80211 specifications. */ --- a/drivers/net/wireless/rt2x00/rt2x00dev.c +++ b/drivers/net/wireless/rt2x00/rt2x00dev.c @@ -686,7 +686,17 @@ static int rt2x00lib_probe_hw(struct rt2 /* * Initialize extra TX headroom required. */ - rt2x00dev->hw->extra_tx_headroom = rt2x00dev->ops->extra_tx_headroom; + rt2x00dev->hw->extra_tx_headroom = + max_t(unsigned int, IEEE80211_TX_STATUS_HEADROOM, + rt2x00dev->ops->extra_tx_headroom); + + /* + * Take TX headroom required for alignment into account. + */ + if (test_bit(DRIVER_REQUIRE_L2PAD, &rt2x00dev->flags)) + rt2x00dev->hw->extra_tx_headroom += RT2X00_L2PAD_SIZE; + else if (test_bit(DRIVER_REQUIRE_DMA, &rt2x00dev->flags)) + rt2x00dev->hw->extra_tx_headroom += RT2X00_ALIGN_SIZE; /* * Register HW.