From nobody Wed Feb 11 02:06:41 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CEDFAC7EE24 for ; Mon, 15 May 2023 09:36:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240471AbjEOJg2 (ORCPT ); Mon, 15 May 2023 05:36:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39898 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238384AbjEOJfe (ORCPT ); Mon, 15 May 2023 05:35:34 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5917010D5 for ; Mon, 15 May 2023 02:34:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1684143282; 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=Di14zlocOEDECmKOzgXOEyS4sjRLATonTy1WJdIXAUU=; b=QmCtWFz2sv4+4ExIDaBlxn9dlcRDT2+WnXn2Sn+ga/JB15WodCzxoJaazbksITpDA1XecD EmpbdVx3VFsgjHkTPcG/dndupWOV1YNlHEQnlJxmcoYaZZfDMmh3Gf/mQKIrdcYFZ1WYRl R9NXjVRySgzEW+xLbR/xMeqVyshqTcQ= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-675-DqP9KNUYOT-s0mTetspL_g-1; Mon, 15 May 2023 05:34:39 -0400 X-MC-Unique: DqP9KNUYOT-s0mTetspL_g-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6ABAF891750; Mon, 15 May 2023 09:34:38 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.42.28.221]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8BC60C15BA0; Mon, 15 May 2023 09:34:35 +0000 (UTC) From: David Howells To: netdev@vger.kernel.org Cc: David Howells , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Willem de Bruijn , David Ahern , Matthew Wilcox , Al Viro , Christoph Hellwig , Jens Axboe , Jeff Layton , Christian Brauner , Chuck Lever III , Linus Torvalds , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH net-next v7 11/16] ip, udp: Support MSG_SPLICE_PAGES Date: Mon, 15 May 2023 10:33:40 +0100 Message-Id: <20230515093345.396978-12-dhowells@redhat.com> In-Reply-To: <20230515093345.396978-1-dhowells@redhat.com> References: <20230515093345.396978-1-dhowells@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Make IP/UDP sendmsg() support MSG_SPLICE_PAGES. This causes pages to be spliced from the source iterator. This allows ->sendpage() to be replaced by something that can handle multiple multipage folios in a single transaction. Signed-off-by: David Howells cc: Willem de Bruijn cc: David Ahern cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: Jens Axboe cc: Matthew Wilcox cc: netdev@vger.kernel.org --- Notes: ver #6) - Use common helper. net/ipv4/ip_output.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 52fc840898d8..c7db973b5d29 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -1048,6 +1048,14 @@ static int __ip_append_data(struct sock *sk, skb_zcopy_set(skb, uarg, &extra_uref); } } + } else if ((flags & MSG_SPLICE_PAGES) && length) { + if (inet->hdrincl) + return -EPERM; + if (rt->dst.dev->features & NETIF_F_SG) + /* We need an empty buffer to attach stuff to */ + paged =3D true; + else + flags &=3D ~MSG_SPLICE_PAGES; } =20 cork->length +=3D length; @@ -1207,6 +1215,15 @@ static int __ip_append_data(struct sock *sk, err =3D -EFAULT; goto error; } + } else if (flags & MSG_SPLICE_PAGES) { + struct msghdr *msg =3D from; + + err =3D skb_splice_from_iter(skb, &msg->msg_iter, copy, + sk->sk_allocation); + if (err < 0) + goto error; + copy =3D err; + wmem_alloc_delta +=3D copy; } else if (!zc) { int i =3D skb_shinfo(skb)->nr_frags;