From patchwork Sat Nov 20 12:39:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sven Eckelmann X-Patchwork-Id: 18416 X-Patchwork-Delegate: sw@simonwunderlich.de Return-Path: X-Original-To: patchwork@open-mesh.org Delivered-To: patchwork@open-mesh.org Received: from diktynna.open-mesh.org (localhost [IPv6:::1]) by diktynna.open-mesh.org (Postfix) with ESMTP id F12DA83F12; Sat, 20 Nov 2021 13:40:14 +0100 (CET) Received: from dvalin.narfation.org (dvalin.narfation.org [IPv6:2a00:17d8:100::8b1]) by diktynna.open-mesh.org (Postfix) with ESMTPS id D894683EEB for ; Sat, 20 Nov 2021 13:40:09 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=narfation.org; s=20121; t=1637412009; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=XHOg4YHyMCg3Xv3zgok7Jnbe/28aOSTPMzRtbJARquw=; b=S+cHCDuHBBK+91vYa6zqpFY3+mr/ltTUqigQTCd43C8yXkg0o0Vv2d4vq35f0jtcDVHFa5 5M/NvN3KLiV03Yz2lEngTV3LKZ5W0wFyUjGioEGyp0hYe97IkoTdzJJoO21ueHnK1tmv2A bVt+/l5tOg2Ltw8GsPr1mFqsa61bLeg= From: Sven Eckelmann To: stable@vger.kernel.org Subject: [PATCH 4.9 6/7] batman-adv: Reserve needed_*room for fragments Date: Sat, 20 Nov 2021 13:39:57 +0100 Message-Id: <20211120123958.260826-7-sven@narfation.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20211120123958.260826-1-sven@narfation.org> References: <20211120123958.260826-1-sven@narfation.org> MIME-Version: 1.0 ARC-Seal: i=1; s=20121; d=open-mesh.org; t=1637412009; a=rsa-sha256; cv=none; b=gRb6iTHGuL7z4lCZuPVeYfsCTAv724cIk3NmA+6uhi3FsuGLPMbHXoYbOoyYVVF2OdcrFv RYk8/otLAl0PqeksIMx2TGZcvEHnusTERuyIoWxD9Gh4WHCFhI1zM1P3RC7VutxtwQrdsn Jst9yumBz+IDj5CV96tI9V681jB1paU= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=open-mesh.org; s=20121; t=1637412009; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=XHOg4YHyMCg3Xv3zgok7Jnbe/28aOSTPMzRtbJARquw=; b=NDwv9jLannOl69aqvHB9c+tI6o7Mt5R6GEEs9e3b0P6FTdf8rdeZuoIBDFMtVGlj+LBwq6 /OEC5TB0+yGANnfm/YkNGG8ekTeTiCig3Ds14JYEwtuo6qVJ+5qZpsUbO7ioyABhDPo4Zf 1XUbM4JlEG51165Oe+6BESynK0SjljA= ARC-Authentication-Results: i=1; diktynna.open-mesh.org; dkim=pass header.d=narfation.org header.s=20121 header.b=S+cHCDuH; spf=pass (diktynna.open-mesh.org: domain of sven@narfation.org designates 2a00:17d8:100::8b1 as permitted sender) smtp.mailfrom=sven@narfation.org; dmarc=pass (policy=none) header.from=narfation.org Message-ID-Hash: XQ4LH3YO3JGM7T2ON34JTEY5OXCXG3NN X-Message-ID-Hash: XQ4LH3YO3JGM7T2ON34JTEY5OXCXG3NN X-MailFrom: sven@narfation.org X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-b.a.t.m.a.n.lists.open-mesh.org-0; header-match-b.a.t.m.a.n.lists.open-mesh.org-1; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; suspicious-header CC: b.a.t.m.a.n@lists.open-mesh.org X-Mailman-Version: 3.2.1 Precedence: list Reply-To: The list for a Better Approach To Mobile Ad-hoc Networking List-Id: The list for a Better Approach To Mobile Ad-hoc Networking Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: commit c5cbfc87558168ef4c3c27ce36eba6b83391db19 upstream. The batadv net_device is trying to propagate the needed_headroom and needed_tailroom from the lower devices. This is needed to avoid cost intensive reallocations using pskb_expand_head during the transmission. But the fragmentation code split the skb's without adding extra room at the end/beginning of the various fragments. This reduced the performance of transmissions over complex scenarios (batadv on vxlan on wireguard) because the lower devices had to perform the reallocations at least once. Fixes: ee75ed88879a ("batman-adv: Fragment and send skbs larger than mtu") Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich [ bp: 4.9 backported: adjust context. ] Signed-off-by: Sven Eckelmann --- net/batman-adv/fragmentation.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/net/batman-adv/fragmentation.c b/net/batman-adv/fragmentation.c index b36606816bac..353772eb4f4d 100644 --- a/net/batman-adv/fragmentation.c +++ b/net/batman-adv/fragmentation.c @@ -394,6 +394,7 @@ bool batadv_frag_skb_fwd(struct sk_buff *skb, /** * batadv_frag_create - create a fragment from skb + * @net_dev: outgoing device for fragment * @skb: skb to create fragment from * @frag_head: header to use in new fragment * @fragment_size: size of new fragment @@ -404,22 +405,25 @@ bool batadv_frag_skb_fwd(struct sk_buff *skb, * * Return: the new fragment, NULL on error. */ -static struct sk_buff *batadv_frag_create(struct sk_buff *skb, +static struct sk_buff *batadv_frag_create(struct net_device *net_dev, + struct sk_buff *skb, struct batadv_frag_packet *frag_head, unsigned int fragment_size) { + unsigned int ll_reserved = LL_RESERVED_SPACE(net_dev); + unsigned int tailroom = net_dev->needed_tailroom; struct sk_buff *skb_fragment; unsigned int header_size = sizeof(*frag_head); unsigned int mtu = fragment_size + header_size; - skb_fragment = netdev_alloc_skb(NULL, mtu + ETH_HLEN); + skb_fragment = dev_alloc_skb(ll_reserved + mtu + tailroom); if (!skb_fragment) goto err; skb_fragment->priority = skb->priority; /* Eat the last mtu-bytes of the skb */ - skb_reserve(skb_fragment, header_size + ETH_HLEN); + skb_reserve(skb_fragment, ll_reserved + header_size); skb_split(skb, skb_fragment, skb->len - fragment_size); /* Add the header */ @@ -443,11 +447,12 @@ int batadv_frag_send_packet(struct sk_buff *skb, struct batadv_orig_node *orig_node, struct batadv_neigh_node *neigh_node) { + struct net_device *net_dev = neigh_node->if_incoming->net_dev; struct batadv_priv *bat_priv; struct batadv_hard_iface *primary_if = NULL; struct batadv_frag_packet frag_header; struct sk_buff *skb_fragment; - unsigned int mtu = neigh_node->if_incoming->net_dev->mtu; + unsigned int mtu = net_dev->mtu; unsigned int header_size = sizeof(frag_header); unsigned int max_fragment_size, num_fragments; int ret = -1; @@ -503,7 +508,7 @@ int batadv_frag_send_packet(struct sk_buff *skb, goto out; } - skb_fragment = batadv_frag_create(skb, &frag_header, + skb_fragment = batadv_frag_create(net_dev, skb, &frag_header, max_fragment_size); if (!skb_fragment) goto out;