From nobody Sun Dec 14 22:12:05 2025 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 4AA74C0015E for ; Fri, 23 Jun 2023 22:57:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232650AbjFWW5R (ORCPT ); Fri, 23 Jun 2023 18:57:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37760 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232532AbjFWW5C (ORCPT ); Fri, 23 Jun 2023 18:57:02 -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 7C4B42738 for ; Fri, 23 Jun 2023 15:55:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1687560945; 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=wPelxPY/D2Xo1HQrs/bARLsTqDBy+xx6UHdo64Xl3wM=; b=HPGy0ncoYa+tas8e3Cc2JoqFo7gXQAwTx/7FS/8NtJSRAim5SF7qTBEScvKDg5XPwb5Gq4 2JIXILqgoNAK8UANbtqsrhomPLiusnxd+qn//05W1l5BVXNeugT1sGch3+6RG8t1E8ebIa N+u3oK2ykr0VIhOZ+jrTrtkzp6DWmRA= 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-499-DUpz--sjP3qXGQTmp0UmAQ-1; Fri, 23 Jun 2023 18:55:41 -0400 X-MC-Unique: DUpz--sjP3qXGQTmp0UmAQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id F295B185A78F; Fri, 23 Jun 2023 22:55:39 +0000 (UTC) Received: from warthog.procyon.org.com (unknown [10.42.28.4]) by smtp.corp.redhat.com (Postfix) with ESMTP id E079340C2063; Fri, 23 Jun 2023 22:55:37 +0000 (UTC) From: David Howells To: netdev@vger.kernel.org Cc: David Howells , Alexander Duyck , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Willem de Bruijn , David Ahern , Matthew Wilcox , Jens Axboe , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Sagi Grimberg , Willem de Bruijn , Keith Busch , Jens Axboe , Christoph Hellwig , Chaitanya Kulkarni , linux-nvme@lists.infradead.org Subject: [PATCH net-next v5 08/16] nvmet-tcp: Use sendmsg(MSG_SPLICE_PAGES) rather then sendpage Date: Fri, 23 Jun 2023 23:55:05 +0100 Message-ID: <20230623225513.2732256-9-dhowells@redhat.com> In-Reply-To: <20230623225513.2732256-1-dhowells@redhat.com> References: <20230623225513.2732256-1-dhowells@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.1 on 10.11.54.1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" When transmitting data, call down into TCP using a single sendmsg with MSG_SPLICE_PAGES to indicate that content should be spliced rather than copied instead of calling sendpage. Signed-off-by: David Howells Tested-by: Sagi Grimberg Acked-by: Willem de Bruijn cc: Keith Busch cc: Jens Axboe cc: Christoph Hellwig cc: Chaitanya Kulkarni cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: Jens Axboe cc: Matthew Wilcox cc: linux-nvme@lists.infradead.org cc: netdev@vger.kernel.org --- Notes: ver #3) - Split nvme/host from nvme/target changes. =20 ver #2) - Wrap lines at 80. drivers/nvme/target/tcp.c | 46 ++++++++++++++++++++++++--------------- 1 file changed, 29 insertions(+), 17 deletions(-) diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c index ed98df72c76b..868aa4de2e4c 100644 --- a/drivers/nvme/target/tcp.c +++ b/drivers/nvme/target/tcp.c @@ -576,13 +576,17 @@ static void nvmet_tcp_execute_request(struct nvmet_tc= p_cmd *cmd) =20 static int nvmet_try_send_data_pdu(struct nvmet_tcp_cmd *cmd) { + struct msghdr msg =3D { + .msg_flags =3D MSG_DONTWAIT | MSG_MORE | MSG_SPLICE_PAGES, + }; + struct bio_vec bvec; u8 hdgst =3D nvmet_tcp_hdgst_len(cmd->queue); int left =3D sizeof(*cmd->data_pdu) - cmd->offset + hdgst; int ret; =20 - ret =3D kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->data_pdu), - offset_in_page(cmd->data_pdu) + cmd->offset, - left, MSG_DONTWAIT | MSG_MORE | MSG_SENDPAGE_NOTLAST); + bvec_set_virt(&bvec, (void *)cmd->data_pdu + cmd->offset, left); + iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, left); + ret =3D sock_sendmsg(cmd->queue->sock, &msg); if (ret <=3D 0) return ret; =20 @@ -603,17 +607,21 @@ static int nvmet_try_send_data(struct nvmet_tcp_cmd *= cmd, bool last_in_batch) int ret; =20 while (cmd->cur_sg) { + struct msghdr msg =3D { + .msg_flags =3D MSG_DONTWAIT | MSG_SPLICE_PAGES, + }; struct page *page =3D sg_page(cmd->cur_sg); + struct bio_vec bvec; u32 left =3D cmd->cur_sg->length - cmd->offset; - int flags =3D MSG_DONTWAIT; =20 if ((!last_in_batch && cmd->queue->send_list_len) || cmd->wbytes_done + left < cmd->req.transfer_len || queue->data_digest || !queue->nvme_sq.sqhd_disabled) - flags |=3D MSG_MORE | MSG_SENDPAGE_NOTLAST; + msg.msg_flags |=3D MSG_MORE; =20 - ret =3D kernel_sendpage(cmd->queue->sock, page, cmd->offset, - left, flags); + bvec_set_page(&bvec, page, left, cmd->offset); + iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, left); + ret =3D sock_sendmsg(cmd->queue->sock, &msg); if (ret <=3D 0) return ret; =20 @@ -649,18 +657,20 @@ static int nvmet_try_send_data(struct nvmet_tcp_cmd *= cmd, bool last_in_batch) static int nvmet_try_send_response(struct nvmet_tcp_cmd *cmd, bool last_in_batch) { + struct msghdr msg =3D { .msg_flags =3D MSG_DONTWAIT | MSG_SPLICE_PAGES, }; + struct bio_vec bvec; u8 hdgst =3D nvmet_tcp_hdgst_len(cmd->queue); int left =3D sizeof(*cmd->rsp_pdu) - cmd->offset + hdgst; - int flags =3D MSG_DONTWAIT; int ret; =20 if (!last_in_batch && cmd->queue->send_list_len) - flags |=3D MSG_MORE | MSG_SENDPAGE_NOTLAST; + msg.msg_flags |=3D MSG_MORE; else - flags |=3D MSG_EOR; + msg.msg_flags |=3D MSG_EOR; =20 - ret =3D kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->rsp_pdu), - offset_in_page(cmd->rsp_pdu) + cmd->offset, left, flags); + bvec_set_virt(&bvec, (void *)cmd->rsp_pdu + cmd->offset, left); + iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, left); + ret =3D sock_sendmsg(cmd->queue->sock, &msg); if (ret <=3D 0) return ret; cmd->offset +=3D ret; @@ -677,18 +687,20 @@ static int nvmet_try_send_response(struct nvmet_tcp_c= md *cmd, =20 static int nvmet_try_send_r2t(struct nvmet_tcp_cmd *cmd, bool last_in_batc= h) { + struct msghdr msg =3D { .msg_flags =3D MSG_DONTWAIT | MSG_SPLICE_PAGES, }; + struct bio_vec bvec; u8 hdgst =3D nvmet_tcp_hdgst_len(cmd->queue); int left =3D sizeof(*cmd->r2t_pdu) - cmd->offset + hdgst; - int flags =3D MSG_DONTWAIT; int ret; =20 if (!last_in_batch && cmd->queue->send_list_len) - flags |=3D MSG_MORE | MSG_SENDPAGE_NOTLAST; + msg.msg_flags |=3D MSG_MORE; else - flags |=3D MSG_EOR; + msg.msg_flags |=3D MSG_EOR; =20 - ret =3D kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->r2t_pdu), - offset_in_page(cmd->r2t_pdu) + cmd->offset, left, flags); + bvec_set_virt(&bvec, (void *)cmd->r2t_pdu + cmd->offset, left); + iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, left); + ret =3D sock_sendmsg(cmd->queue->sock, &msg); if (ret <=3D 0) return ret; cmd->offset +=3D ret;