From patchwork Sat Nov 20 12:40:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sven Eckelmann X-Patchwork-Id: 18422 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 DA2928447B; Sat, 20 Nov 2021 13:40:24 +0100 (CET) Received: from dvalin.narfation.org (dvalin.narfation.org [IPv6:2a00:17d8:100::8b1]) by diktynna.open-mesh.org (Postfix) with ESMTPS id 75DF283DB1 for ; Sat, 20 Nov 2021 13:40:22 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=narfation.org; s=20121; t=1637412022; 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=UFOzYMAeSL48Cu2QrNvFfL68SSI9xsCNb7YyL0zH0QI=; b=tG2XxwVbBNOmKyB49Zy6BirClyPRJctKBEoxWjXFQyiRsmw1bzQE/TeC6wFrk8KGjikt7r JtZs2sbZU1D49s+0GgVPdFiIuy29J9JY7+P/WKUSPLEoX9dvKIxjR3KvRjF+qSUx3Wjqek Yv1QmpnckL0D/oi2pNZGC4YBnT7JSDA= From: Sven Eckelmann To: stable@vger.kernel.org Subject: [PATCH 4.14 4/5] batman-adv: Reserve needed_*room for fragments Date: Sat, 20 Nov 2021 13:40:17 +0100 Message-Id: <20211120124018.260907-5-sven@narfation.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20211120124018.260907-1-sven@narfation.org> References: <20211120124018.260907-1-sven@narfation.org> MIME-Version: 1.0 ARC-Seal: i=1; s=20121; d=open-mesh.org; t=1637412022; a=rsa-sha256; cv=none; b=lhYK8TdDbLfpmGq3xGpwGLUYmtetPmFkvs4s1ODmxhk3x1AHCRHjoJKccqstUHJ6plwGEy ouCn8GlXKEwoiKyuQDFW+b7mMDMj89P59UdZn2LsP4NposodSYCk864Jo9E8LcmnF5Ghl1 i+oF1Qjtxt3cLZcoihs0c641TGrywDU= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=open-mesh.org; s=20121; t=1637412022; 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=UFOzYMAeSL48Cu2QrNvFfL68SSI9xsCNb7YyL0zH0QI=; b=qfqp2MY83kQIocZGveB76G0kXD7kJLubvyKdC70f7HMJ0acObnHtG3mbIfuV99h7Reb+jv kCsQuthBvYfoYZsu+/f3OEADS4k/N6GBL6OnwgN6nX/mQN6esbkS29ytZQOlpBDD2ZRiBG 3vpa4xyGyJ7Rrtgle4sXVuv9ykHo6PI= ARC-Authentication-Results: i=1; diktynna.open-mesh.org; dkim=pass header.d=narfation.org header.s=20121 header.b=tG2XxwVb; 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: SJIN2EUMWD2WVE6S3Q6FZYZW22DWPOZQ X-Message-ID-Hash: SJIN2EUMWD2WVE6S3Q6FZYZW22DWPOZQ 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: 4.14 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 788d62073964..f1446a04f055 100644 --- a/net/batman-adv/fragmentation.c +++ b/net/batman-adv/fragmentation.c @@ -402,6 +402,7 @@ 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 @@ -412,22 +413,25 @@ 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 */ @@ -450,11 +454,12 @@ 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; @@ -514,7 +519,7 @@ int batadv_frag_send_packet(struct sk_buff *skb, goto put_primary_if; } - skb_fragment = batadv_frag_create(skb, &frag_header, + skb_fragment = batadv_frag_create(net_dev, skb, &frag_header, max_fragment_size); if (!skb_fragment) { ret = -ENOMEM;