From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 806CAC31E46 for ; Wed, 12 Jun 2019 08:58:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6233120866 for ; Wed, 12 Jun 2019 08:58:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390115AbfFLI6w (ORCPT ); Wed, 12 Jun 2019 04:58:52 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60358 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725938AbfFLI6w (ORCPT ); Wed, 12 Jun 2019 04:58:52 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 9ED143082DD3; Wed, 12 Jun 2019 08:58:51 +0000 (UTC) Received: from localhost (unknown [10.43.2.57]) by smtp.corp.redhat.com (Postfix) with ESMTP id 53AFE17B6D; Wed, 12 Jun 2019 08:58:47 +0000 (UTC) Date: Wed, 12 Jun 2019 10:58:45 +0200 From: Stanislaw Gruszka To: Lorenzo Bianconi Cc: nbd@nbd.name, kvalo@codeaurora.org, linux-wireless@vger.kernel.org, lorenzo.bianconi@redhat.com Subject: Re: [PATCH v2 1/2] mt76: usb: fix rx A-MSDU support Message-ID: <20190612085844.GA2965@redhat.com> References: <52ea155d9889aa15df44b4910806b74fa2fd9056.1559293385.git.lorenzo@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <52ea155d9889aa15df44b4910806b74fa2fd9056.1559293385.git.lorenzo@kernel.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.46]); Wed, 12 Jun 2019 08:58:51 +0000 (UTC) Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org Hi and sorry for late comment. On Fri, May 31, 2019 at 11:38:22AM +0200, Lorenzo Bianconi wrote: > Commit f8f527b16db5 ("mt76: usb: use EP max packet aligned buffer sizes > for rx") breaks A-MSDU support. When A-MSDU is enable the device can > receive frames up to q->buf_size but they will be discarded in > mt76u_process_rx_entry since there is no enough room for > skb_shared_info. Fix the issue reallocating the skb and copying in the > linear area the first 128B of the received frames and in the frag_list > the remaining part. > > Fixes: f8f527b16db5 ("mt76: usb: use EP max packet aligned buffer sizes for rx") > Signed-off-by: Lorenzo Bianconi > --- > drivers/net/wireless/mediatek/mt76/mt76.h | 1 + > drivers/net/wireless/mediatek/mt76/usb.c | 52 +++++++++++++++++++---- > 2 files changed, 44 insertions(+), 9 deletions(-) > > diff --git a/drivers/net/wireless/mediatek/mt76/mt76.h b/drivers/net/wireless/mediatek/mt76/mt76.h > index 97a1296562d0..74d4edf941d6 100644 > --- a/drivers/net/wireless/mediatek/mt76/mt76.h > +++ b/drivers/net/wireless/mediatek/mt76/mt76.h > @@ -30,6 +30,7 @@ > #define MT_TX_RING_SIZE 256 > #define MT_MCU_RING_SIZE 32 > #define MT_RX_BUF_SIZE 2048 > +#define MT_SKB_HEAD_LEN 128 > > struct mt76_dev; > struct mt76_wcid; > diff --git a/drivers/net/wireless/mediatek/mt76/usb.c b/drivers/net/wireless/mediatek/mt76/usb.c > index bbaa1365bbda..2bfc8214c0d8 100644 > --- a/drivers/net/wireless/mediatek/mt76/usb.c > +++ b/drivers/net/wireless/mediatek/mt76/usb.c > @@ -429,6 +429,48 @@ static int mt76u_get_rx_entry_len(u8 *data, u32 data_len) > return dma_len; > } > > +static struct sk_buff * > +mt76u_build_rx_skb(u8 *data, int len, int buf_size, > + int *nsgs) > +{ > + int data_len = min(len, MT_SKB_HEAD_LEN); > + struct sk_buff *skb; > + > + if (SKB_WITH_OVERHEAD(buf_size) >= MT_DMA_HDR_LEN + len) { > + /* fast path */ > + skb = build_skb(data, buf_size); > + if (!skb) > + return NULL; > + > + skb_reserve(skb, MT_DMA_HDR_LEN); > + __skb_put(skb, len); > + > + return skb; > + } > + > + /* slow path, not enough space for data and > + * skb_shared_info > + */ > + skb = alloc_skb(data_len, GFP_ATOMIC); > + if (!skb) > + return NULL; > + > + skb_put_data(skb, data + MT_DMA_HDR_LEN, data_len); mt7601u and iwlmvm just copy hdrlen + 8 and put the rest of the buffer in fragment, which supose to be more efficient, see comment in iwl_mvm_pass_packet_to_mac80211(). > + data += (data_len + MT_DMA_HDR_LEN); > + len -= data_len; > + if (len > 0) { > + struct page *page = virt_to_head_page(data); > + int offset = data - (u8 *)page_address(page); u8 cast not needed. > + skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, > + page, offset, len, buf_size); > + } else { > + *nsgs = 0; This seems to be not necessary or a bug (use first buffer 2 times). Stanislaw