From patchwork Mon Apr 23 05:34:53 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 10356191 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 640A1601BE for ; Mon, 23 Apr 2018 05:38:19 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5686528931 for ; Mon, 23 Apr 2018 05:38:19 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4B176289B8; Mon, 23 Apr 2018 05:38:19 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C5D8528931 for ; Mon, 23 Apr 2018 05:38:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751510AbeDWFfS (ORCPT ); Mon, 23 Apr 2018 01:35:18 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:52512 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751117AbeDWFfO (ORCPT ); Mon, 23 Apr 2018 01:35:14 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8F954406F8B0; Mon, 23 Apr 2018 05:35:13 +0000 (UTC) Received: from jason-ThinkPad-T450s.redhat.com (ovpn-12-101.pek2.redhat.com [10.72.12.101]) by smtp.corp.redhat.com (Postfix) with ESMTP id EBC882022DEB; Mon, 23 Apr 2018 05:35:09 +0000 (UTC) From: Jason Wang To: mst@redhat.com, jasowang@redhat.com Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, tiwei.bie@intel.com, jfreimann@redhat.com, wexu@redhat.com Subject: [RFC V3 PATCH 1/8] vhost: move get_rx_bufs to vhost.c Date: Mon, 23 Apr 2018 13:34:53 +0800 Message-Id: <1524461700-5469-2-git-send-email-jasowang@redhat.com> In-Reply-To: <1524461700-5469-1-git-send-email-jasowang@redhat.com> References: <1524461700-5469-1-git-send-email-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Mon, 23 Apr 2018 05:35:13 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Mon, 23 Apr 2018 05:35:13 +0000 (UTC) for IP:'10.11.54.4' DOMAIN:'int-mx04.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'jasowang@redhat.com' RCPT:'' Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Move get_rx_bufs() to vhost.c and rename it to vhost_get_rx_bufs(). This helps to hide vring internal layout from specific device implementation. Packed ring implementation will benefit from this. Signed-off-by: Jason Wang --- drivers/vhost/net.c | 83 ++------------------------------------------------- drivers/vhost/vhost.c | 78 +++++++++++++++++++++++++++++++++++++++++++++++ drivers/vhost/vhost.h | 7 +++++ 3 files changed, 88 insertions(+), 80 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 986058a..762aa81 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -664,83 +664,6 @@ static int vhost_net_rx_peek_head_len(struct vhost_net *net, struct sock *sk) return len; } -/* This is a multi-buffer version of vhost_get_desc, that works if - * vq has read descriptors only. - * @vq - the relevant virtqueue - * @datalen - data length we'll be reading - * @iovcount - returned count of io vectors we fill - * @log - vhost log - * @log_num - log offset - * @quota - headcount quota, 1 for big buffer - * returns number of buffer heads allocated, negative on error - */ -static int get_rx_bufs(struct vhost_virtqueue *vq, - struct vring_used_elem *heads, - int datalen, - unsigned *iovcount, - struct vhost_log *log, - unsigned *log_num, - unsigned int quota) -{ - unsigned int out, in; - int seg = 0; - int headcount = 0; - unsigned d; - int r, nlogs = 0; - /* len is always initialized before use since we are always called with - * datalen > 0. - */ - u32 uninitialized_var(len); - - while (datalen > 0 && headcount < quota) { - if (unlikely(seg >= UIO_MAXIOV)) { - r = -ENOBUFS; - goto err; - } - r = vhost_get_vq_desc(vq, vq->iov + seg, - ARRAY_SIZE(vq->iov) - seg, &out, - &in, log, log_num); - if (unlikely(r < 0)) - goto err; - - d = r; - if (d == vq->num) { - r = 0; - goto err; - } - if (unlikely(out || in <= 0)) { - vq_err(vq, "unexpected descriptor format for RX: " - "out %d, in %d\n", out, in); - r = -EINVAL; - goto err; - } - if (unlikely(log)) { - nlogs += *log_num; - log += *log_num; - } - heads[headcount].id = cpu_to_vhost32(vq, d); - len = iov_length(vq->iov + seg, in); - heads[headcount].len = cpu_to_vhost32(vq, len); - datalen -= len; - ++headcount; - seg += in; - } - heads[headcount - 1].len = cpu_to_vhost32(vq, len + datalen); - *iovcount = seg; - if (unlikely(log)) - *log_num = nlogs; - - /* Detect overrun */ - if (unlikely(datalen > 0)) { - r = UIO_MAXIOV + 1; - goto err; - } - return headcount; -err: - vhost_discard_vq_desc(vq, headcount); - return r; -} - /* Expects to be always run from workqueue - which acts as * read-size critical section for our kind of RCU. */ static void handle_rx(struct vhost_net *net) @@ -790,9 +713,9 @@ static void handle_rx(struct vhost_net *net) while ((sock_len = vhost_net_rx_peek_head_len(net, sock->sk))) { sock_len += sock_hlen; vhost_len = sock_len + vhost_hlen; - headcount = get_rx_bufs(vq, vq->heads + nheads, vhost_len, - &in, vq_log, &log, - likely(mergeable) ? UIO_MAXIOV : 1); + headcount = vhost_get_bufs(vq, vq->heads + nheads, vhost_len, + &in, vq_log, &log, + likely(mergeable) ? UIO_MAXIOV : 1); /* On error, stop handling until the next kick. */ if (unlikely(headcount < 0)) goto out; diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index f3bd8e9..6b455f6 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -2097,6 +2097,84 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, } EXPORT_SYMBOL_GPL(vhost_get_vq_desc); +/* This is a multi-buffer version of vhost_get_desc, that works if + * vq has read descriptors only. + * @vq - the relevant virtqueue + * @datalen - data length we'll be reading + * @iovcount - returned count of io vectors we fill + * @log - vhost log + * @log_num - log offset + * @quota - headcount quota, 1 for big buffer + * returns number of buffer heads allocated, negative on error + */ +int vhost_get_bufs(struct vhost_virtqueue *vq, + struct vring_used_elem *heads, + int datalen, + unsigned *iovcount, + struct vhost_log *log, + unsigned *log_num, + unsigned int quota) +{ + unsigned int out, in; + int seg = 0; + int headcount = 0; + unsigned d; + int r, nlogs = 0; + /* len is always initialized before use since we are always called with + * datalen > 0. + */ + u32 uninitialized_var(len); + + while (datalen > 0 && headcount < quota) { + if (unlikely(seg >= UIO_MAXIOV)) { + r = -ENOBUFS; + goto err; + } + r = vhost_get_vq_desc(vq, vq->iov + seg, + ARRAY_SIZE(vq->iov) - seg, &out, + &in, log, log_num); + if (unlikely(r < 0)) + goto err; + + d = r; + if (d == vq->num) { + r = 0; + goto err; + } + if (unlikely(out || in <= 0)) { + vq_err(vq, "unexpected descriptor format for RX: " + "out %d, in %d\n", out, in); + r = -EINVAL; + goto err; + } + if (unlikely(log)) { + nlogs += *log_num; + log += *log_num; + } + heads[headcount].id = cpu_to_vhost32(vq, d); + len = iov_length(vq->iov + seg, in); + heads[headcount].len = cpu_to_vhost32(vq, len); + datalen -= len; + ++headcount; + seg += in; + } + heads[headcount - 1].len = cpu_to_vhost32(vq, len + datalen); + *iovcount = seg; + if (unlikely(log)) + *log_num = nlogs; + + /* Detect overrun */ + if (unlikely(datalen > 0)) { + r = UIO_MAXIOV + 1; + goto err; + } + return headcount; +err: + vhost_discard_vq_desc(vq, headcount); + return r; +} +EXPORT_SYMBOL_GPL(vhost_get_bufs); + /* Reverse the effect of vhost_get_vq_desc. Useful for error handling. */ void vhost_discard_vq_desc(struct vhost_virtqueue *vq, int n) { diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index 6c844b9..52edd242 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -185,6 +185,13 @@ int vhost_get_vq_desc(struct vhost_virtqueue *, struct iovec iov[], unsigned int iov_count, unsigned int *out_num, unsigned int *in_num, struct vhost_log *log, unsigned int *log_num); +int vhost_get_bufs(struct vhost_virtqueue *vq, + struct vring_used_elem *heads, + int datalen, + unsigned *iovcount, + struct vhost_log *log, + unsigned *log_num, + unsigned int quota); void vhost_discard_vq_desc(struct vhost_virtqueue *, int n); int vhost_vq_init_access(struct vhost_virtqueue *);