From patchwork Thu Mar 16 15:26:10 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 13177898 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 C01C0C6FD19 for ; Thu, 16 Mar 2023 15:30:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231670AbjCPPah (ORCPT ); Thu, 16 Mar 2023 11:30:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33338 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231604AbjCPP3e (ORCPT ); Thu, 16 Mar 2023 11:29:34 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4102A474EE for ; Thu, 16 Mar 2023 08:27:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1678980453; 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=cqdl8fmtEvVwpgPJdtUvP824my58WFWl8Wp/Vt/z1XI=; b=LTHiqnSwge0gw8ut7mpVVCgNnuZ60n0yYQIBbe4vgdxTnDBVUCgu8/+9bjiaP8G0WR20J0 XbTYzc0dr7TC9GJL3psMXzR38daXOhDMBYAH+evAiDx/BIekArseeaNx5NlQRfGtzkN477 DEoA0hFfHWuY6jpVj5n4GK4TZ002Ivg= 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-644-1WZJi73lMMOMNIGU82y0ZA-1; Thu, 16 Mar 2023 11:27:22 -0400 X-MC-Unique: 1WZJi73lMMOMNIGU82y0ZA-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id B5D4E185A78F; Thu, 16 Mar 2023 15:27:15 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.36.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9C1A1140EBF4; Thu, 16 Mar 2023 15:27:13 +0000 (UTC) From: David Howells To: Matthew Wilcox , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: David Howells , Al Viro , Christoph Hellwig , Jens Axboe , Jeff Layton , Christian Brauner , Linus Torvalds , netdev@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, "Martin K. Petersen" , linux-scsi@vger.kernel.org, target-devel@vger.kernel.org Subject: [RFC PATCH 20/28] iscsi: Use sendmsg(MSG_SPLICE_PAGES) rather than sendpage Date: Thu, 16 Mar 2023 15:26:10 +0000 Message-Id: <20230316152618.711970-21-dhowells@redhat.com> In-Reply-To: <20230316152618.711970-1-dhowells@redhat.com> References: <20230316152618.711970-1-dhowells@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Use sendmsg() with MSG_SPLICE_PAGES rather than sendpage. This allows multiple pages and multipage folios to be passed through. TODO: iscsit_fe_sendpage_sg() should perhaps set up a bio_vec array for the entire set of pages it's going to transfer plus two for the header and trailer and use zcopy_alloc() to allocate the header and trailer - and then call sendmsg once for the entire message. Signed-off-by: David Howells cc: "Martin K. Petersen" cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: Jens Axboe cc: Matthew Wilcox cc: linux-scsi@vger.kernel.org cc: target-devel@vger.kernel.org cc: netdev@vger.kernel.org --- drivers/target/iscsi/iscsi_target_util.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/target/iscsi/iscsi_target_util.c b/drivers/target/iscsi/iscsi_target_util.c index 26dc8ed3045b..c7d58e41ac3b 100644 --- a/drivers/target/iscsi/iscsi_target_util.c +++ b/drivers/target/iscsi/iscsi_target_util.c @@ -1078,6 +1078,8 @@ int iscsit_fe_sendpage_sg( struct iscsit_conn *conn) { struct scatterlist *sg = cmd->first_data_sg; + struct bio_vec bvec; + struct msghdr msghdr = { .msg_flags = MSG_SPLICE_PAGES, }; struct kvec iov; u32 tx_hdr_size, data_len; u32 offset = cmd->first_data_sg_off; @@ -1121,17 +1123,17 @@ int iscsit_fe_sendpage_sg( u32 space = (sg->length - offset); u32 sub_len = min_t(u32, data_len, space); send_pg: - tx_sent = conn->sock->ops->sendpage(conn->sock, - sg_page(sg), sg->offset + offset, sub_len, 0); + bvec_set_page(&bvec, sg_page(sg), sub_len, sg->offset + offset); + iov_iter_bvec(&msghdr.msg_iter, ITER_SOURCE, &bvec, 1, sub_len); + + tx_sent = conn->sock->ops->sendmsg(conn->sock, &msghdr, sub_len); if (tx_sent != sub_len) { if (tx_sent == -EAGAIN) { - pr_err("tcp_sendpage() returned" - " -EAGAIN\n"); + pr_err("sendmsg/splice returned -EAGAIN\n"); goto send_pg; } - pr_err("tcp_sendpage() failure: %d\n", - tx_sent); + pr_err("sendmsg/splice failure: %d\n", tx_sent); return -1; }