From patchwork Mon Jul 17 21:00:48 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arseniy Krasnov X-Patchwork-Id: 121614 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:c923:0:b0:3e4:2afc:c1 with SMTP id j3csp1359238vqt; Mon, 17 Jul 2023 14:42:51 -0700 (PDT) X-Google-Smtp-Source: APBJJlHCOYGGl6PPEDEfXZN5Bva0phP9VPvlXslrzzlJ1gvyWqRxEj2I4TPXFXJOV8Bo420oDwsn X-Received: by 2002:a05:6402:744:b0:50b:c693:70af with SMTP id p4-20020a056402074400b0050bc69370afmr11606623edy.2.1689630170866; Mon, 17 Jul 2023 14:42:50 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1689630170; cv=none; d=google.com; s=arc-20160816; b=UKSHujRVdFrABE0Dc1Qx+agwkL8VZbXwabZ5+Vp+3Ph9EnU9YvxV0WhYRTHq8vUKAj 1VN/ObqGTessjjH8SonWFy3j1J3nLVUIA4Z8gd8MYJjgiHHTEJZ1Zx07zicdMYAlfhCm 2SfkXE+dkOPW6XzjNHlg6aFaAhkGzR8lL2g39fMJzCcJoH5VVVrDKpTiauHf+pSekSKD GGf9vo5L0zd3PM5tYMb7K5H2lwHnsP9gNMeJE0n+iChqPT8pEgyMb0eGy7kmWLXicqcF OAb5CnSk1aDxN8jij/VY+8q1SoEYarTLJdnLsbQX8lyaiGAAW+Uv7vHkrYqtYQkD77Z2 0IjQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature:dkim-filter; bh=cd1IOAcuYzKWX8jCc2ym7vhBB+ONo5JKwu2/WLdhWSw=; fh=IiLlUAYZQ4hWuQbi3V9KE00VdjFsw4tg4Y6JCUFRLn0=; b=BNKYKoZiPHqojA3EWF80cbGsVfpj9RnhjD0fXxoo89mKBzVpddCJv9kXNlU6EZEdyJ nYqynqlarzE8mGBqS11l1tO+IHPHNq0fJO3j2sn821XClYRDlIu/TknNZ2pnNdGCONj6 l396bBESThzC9arRVLeN4Ac3Zczf1idyik81Kd0Z/P7dPwJaJhcJD8U3DCaR0iGSZ5wK NWpA8uJazIjWZOD5i8zaRzWJKPkl1YyZlICL+Wv9aoJWYhBsEN289KST9mVRhe66nFaO i1xwsxwPQ4bC7jbrF5MgCGpoNYvDmVmETdxshDCiXaIeq9gmxgj8+UI6b4SsxZ37BPmA 1UUg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@sberdevices.ru header.s=mail header.b=Mrcy55bf; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=sberdevices.ru Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id t18-20020a05640203d200b005219817ce6bsi185621edw.88.2023.07.17.14.42.26; Mon, 17 Jul 2023 14:42:50 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@sberdevices.ru header.s=mail header.b=Mrcy55bf; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=sberdevices.ru Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230297AbjGQVGl (ORCPT + 99 others); Mon, 17 Jul 2023 17:06:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49146 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231197AbjGQVGa (ORCPT ); Mon, 17 Jul 2023 17:06:30 -0400 Received: from mx1.sberdevices.ru (mx1.sberdevices.ru [37.18.73.165]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 537E2118; Mon, 17 Jul 2023 14:06:28 -0700 (PDT) Received: from p-infra-ksmg-sc-msk01 (localhost [127.0.0.1]) by mx1.sberdevices.ru (Postfix) with ESMTP id 4B2F2100011; Tue, 18 Jul 2023 00:06:26 +0300 (MSK) DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.sberdevices.ru 4B2F2100011 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sberdevices.ru; s=mail; t=1689627986; bh=cd1IOAcuYzKWX8jCc2ym7vhBB+ONo5JKwu2/WLdhWSw=; h=From:To:Subject:Date:Message-ID:MIME-Version:Content-Type:From; b=Mrcy55bfLFbLLvpRvwd83v57Tp8ZGr2+g3dd+dQ+3yVaJCK3lPbJf2sPoRoJtTx1J 1kWLkqEjrhBrpzhOIubxhippkRtpbGRXi+S1WQMRnRZqREwwEB/7NxcDLTLADruAUL bhkE7qBujk3RWmmfYItQ3H51SOSi8B1/z8crN+p410Tz0rOz0Pkf7CEiWoiMUYHdfg 3bKzcVwFRNM5qp9H7kU9qwoplZ7b9CHGm5mWTDLGI9FueYUT3e/OLtxirjY02lkr3B N81lLdk7xP3paNQYZHHU2WrZpY0aHEiBkcbobBGHlFe2UBmWicrF9BijDNasZjsWHQ 1Uo/TPhbOftSw== Received: from p-i-exch-sc-m01.sberdevices.ru (p-i-exch-sc-m01.sberdevices.ru [172.16.192.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.sberdevices.ru (Postfix) with ESMTPS; Tue, 18 Jul 2023 00:06:26 +0300 (MSK) Received: from localhost.localdomain (100.64.160.123) by p-i-exch-sc-m01.sberdevices.ru (172.16.192.107) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.30; Tue, 18 Jul 2023 00:06:25 +0300 From: Arseniy Krasnov To: Stefan Hajnoczi , Stefano Garzarella , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , "Michael S. Tsirkin" , Jason Wang , Bobby Eshleman CC: , , , , , , , Arseniy Krasnov Subject: [PATCH net-next v1 1/4] vsock/virtio/vhost: read data from non-linear skb Date: Tue, 18 Jul 2023 00:00:48 +0300 Message-ID: <20230717210051.856388-2-AVKrasnov@sberdevices.ru> X-Mailer: git-send-email 2.35.0 In-Reply-To: <20230717210051.856388-1-AVKrasnov@sberdevices.ru> References: <20230717210051.856388-1-AVKrasnov@sberdevices.ru> MIME-Version: 1.0 X-Originating-IP: [100.64.160.123] X-ClientProxiedBy: p-i-exch-sc-m01.sberdevices.ru (172.16.192.107) To p-i-exch-sc-m01.sberdevices.ru (172.16.192.107) X-KSMG-Rule-ID: 10 X-KSMG-Message-Action: clean X-KSMG-AntiSpam-Lua-Profiles: 178666 [Jul 17 2023] X-KSMG-AntiSpam-Version: 5.9.59.0 X-KSMG-AntiSpam-Envelope-From: AVKrasnov@sberdevices.ru X-KSMG-AntiSpam-Rate: 0 X-KSMG-AntiSpam-Status: not_detected X-KSMG-AntiSpam-Method: none X-KSMG-AntiSpam-Auth: dkim=none X-KSMG-AntiSpam-Info: LuaCore: 523 523 523027ce26ed1d9067f7a52a4756a876e54db27c, {Tracking_from_domain_doesnt_match_to}, 100.64.160.123:7.1.2;sberdevices.ru:5.0.1,7.1.1;p-i-exch-sc-m01.sberdevices.ru:5.0.1,7.1.1;127.0.0.199:7.1.2;d41d8cd98f00b204e9800998ecf8427e.com:7.1.1, FromAlignment: s, {Tracking_white_helo}, ApMailHostAddress: 100.64.160.123 X-MS-Exchange-Organization-SCL: -1 X-KSMG-AntiSpam-Interceptor-Info: scan successful X-KSMG-AntiPhishing: Clean X-KSMG-LinksScanning: Clean X-KSMG-AntiVirus: Kaspersky Secure Mail Gateway, version 2.0.1.6960, bases: 2023/07/17 13:15:00 #21627216 X-KSMG-AntiVirus-Status: Clean, skipped X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_BLOCKED, SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1771705646261444817 X-GMAIL-MSGID: 1771705646261444817 This is preparation patch for MSG_ZEROCOPY support. It adds handling of non-linear skbs by replacing direct calls of 'memcpy_to_msg()' with 'skb_copy_datagram_iter()'. Main advantage of the second one is that it can handle paged part of the skb by using 'kmap()' on each page, but if there are no pages in the skb, it behaves like simple copying to iov iterator. This patch also adds new field to the control block of skb - this value shows current offset in the skb to read next portion of data (it doesn't matter linear it or not). Idea behind this field is that 'skb_copy_datagram_iter()' handles both types of skb internally - it just needs an offset from which to copy data from the given skb. This offset is incremented on each read from skb. This approach allows to avoid special handling of non-linear skbs: 1) We can't call 'skb_pull()' on it, because it updates 'data' pointer. 2) We need to update 'data_len' also on each read from this skb. Signed-off-by: Arseniy Krasnov Reviewed-by: Stefano Garzarella --- Changelog: v5(big patchset) -> v1: * Merge 'virtio_transport_common.c' and 'vhost/vsock.c' patches into this single patch. * Commit message update: grammar fix and remark that this patch is MSG_ZEROCOPY preparation. * Use 'min_t()' instead of comparison using '<>' operators. drivers/vhost/vsock.c | 14 ++++++++----- include/linux/virtio_vsock.h | 1 + net/vmw_vsock/virtio_transport_common.c | 27 ++++++++++++++++--------- 3 files changed, 28 insertions(+), 14 deletions(-) diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c index 817d377a3f36..8c917be32b5d 100644 --- a/drivers/vhost/vsock.c +++ b/drivers/vhost/vsock.c @@ -114,6 +114,7 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock, struct sk_buff *skb; unsigned out, in; size_t nbytes; + u32 frag_off; int head; skb = virtio_vsock_skb_dequeue(&vsock->send_pkt_queue); @@ -156,7 +157,8 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock, } iov_iter_init(&iov_iter, ITER_DEST, &vq->iov[out], in, iov_len); - payload_len = skb->len; + frag_off = VIRTIO_VSOCK_SKB_CB(skb)->frag_off; + payload_len = skb->len - frag_off; hdr = virtio_vsock_hdr(skb); /* If the packet is greater than the space available in the @@ -197,8 +199,10 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock, break; } - nbytes = copy_to_iter(skb->data, payload_len, &iov_iter); - if (nbytes != payload_len) { + if (skb_copy_datagram_iter(skb, + frag_off, + &iov_iter, + payload_len)) { kfree_skb(skb); vq_err(vq, "Faulted on copying pkt buf\n"); break; @@ -212,13 +216,13 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock, vhost_add_used(vq, head, sizeof(*hdr) + payload_len); added = true; - skb_pull(skb, payload_len); + VIRTIO_VSOCK_SKB_CB(skb)->frag_off += payload_len; total_len += payload_len; /* If we didn't send all the payload we can requeue the packet * to send it with the next available buffer. */ - if (skb->len > 0) { + if (VIRTIO_VSOCK_SKB_CB(skb)->frag_off < skb->len) { hdr->flags |= cpu_to_le32(flags_to_restore); /* We are queueing the same skb to handle diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h index c58453699ee9..17dbb7176e37 100644 --- a/include/linux/virtio_vsock.h +++ b/include/linux/virtio_vsock.h @@ -12,6 +12,7 @@ struct virtio_vsock_skb_cb { bool reply; bool tap_delivered; + u32 frag_off; }; #define VIRTIO_VSOCK_SKB_CB(skb) ((struct virtio_vsock_skb_cb *)((skb)->cb)) diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index b769fc258931..1a376f808ae6 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -355,7 +355,7 @@ virtio_transport_stream_do_peek(struct vsock_sock *vsk, spin_lock_bh(&vvs->rx_lock); skb_queue_walk_safe(&vvs->rx_queue, skb, tmp) { - off = 0; + off = VIRTIO_VSOCK_SKB_CB(skb)->frag_off; if (total == len) break; @@ -370,7 +370,10 @@ virtio_transport_stream_do_peek(struct vsock_sock *vsk, */ spin_unlock_bh(&vvs->rx_lock); - err = memcpy_to_msg(msg, skb->data + off, bytes); + err = skb_copy_datagram_iter(skb, off, + &msg->msg_iter, + bytes); + if (err) goto out; @@ -413,25 +416,28 @@ virtio_transport_stream_do_dequeue(struct vsock_sock *vsk, while (total < len && !skb_queue_empty(&vvs->rx_queue)) { skb = skb_peek(&vvs->rx_queue); - bytes = len - total; - if (bytes > skb->len) - bytes = skb->len; + bytes = min_t(size_t, len - total, + skb->len - VIRTIO_VSOCK_SKB_CB(skb)->frag_off); /* sk_lock is held by caller so no one else can dequeue. * Unlock rx_lock since memcpy_to_msg() may sleep. */ spin_unlock_bh(&vvs->rx_lock); - err = memcpy_to_msg(msg, skb->data, bytes); + err = skb_copy_datagram_iter(skb, + VIRTIO_VSOCK_SKB_CB(skb)->frag_off, + &msg->msg_iter, bytes); + if (err) goto out; spin_lock_bh(&vvs->rx_lock); total += bytes; - skb_pull(skb, bytes); - if (skb->len == 0) { + VIRTIO_VSOCK_SKB_CB(skb)->frag_off += bytes; + + if (skb->len == VIRTIO_VSOCK_SKB_CB(skb)->frag_off) { u32 pkt_len = le32_to_cpu(virtio_vsock_hdr(skb)->len); virtio_transport_dec_rx_pkt(vvs, pkt_len); @@ -503,7 +509,10 @@ static int virtio_transport_seqpacket_do_dequeue(struct vsock_sock *vsk, */ spin_unlock_bh(&vvs->rx_lock); - err = memcpy_to_msg(msg, skb->data, bytes_to_copy); + err = skb_copy_datagram_iter(skb, 0, + &msg->msg_iter, + bytes_to_copy); + if (err) { /* Copy of message failed. Rest of * fragments will be freed without copy.