From patchwork Mon Jan 25 18:01:11 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vivek Goyal X-Patchwork-Id: 1431314 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=dDt9MElG; dkim-atps=neutral Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4DPd5h0wwsz9sT6 for ; Tue, 26 Jan 2021 05:03:33 +1100 (AEDT) Received: from localhost ([::1]:38304 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l46D3-0001QL-NB for incoming@patchwork.ozlabs.org; Mon, 25 Jan 2021 13:03:29 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:45186) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l46Bc-0001OV-0R for qemu-devel@nongnu.org; Mon, 25 Jan 2021 13:02:00 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:57761) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1l46BY-0006km-Up for qemu-devel@nongnu.org; Mon, 25 Jan 2021 13:01:59 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1611597714; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Go5qmUqyPVhLjJ+A7W/OFRJFVNMBRxbvYLjmjXBhUUo=; b=dDt9MElGp4Nvy1J3SOUFgxbUKmOc/pAIJ3gBVpXubRQnOGTSInz6SgAERUYSDxFXO9KdmU qjMzdOLpci/7QuVsZY9sSaFck1K/uXbky8+35i3HdJWrCsAuKnFfGv14qSrLmMY2vkXUuU Ae9Fzmcs2kEvOCTkgWSkTPjNpK+WCsA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-532-EsoIWbSdO1K3EDcob8FgWQ-1; Mon, 25 Jan 2021 13:01:52 -0500 X-MC-Unique: EsoIWbSdO1K3EDcob8FgWQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C1C80100C606 for ; Mon, 25 Jan 2021 18:01:51 +0000 (UTC) Received: from horse.redhat.com (ovpn-116-119.rdu2.redhat.com [10.10.116.119]) by smtp.corp.redhat.com (Postfix) with ESMTP id A16D26F983; Mon, 25 Jan 2021 18:01:38 +0000 (UTC) Received: by horse.redhat.com (Postfix, from userid 10451) id 39C61223D99; Mon, 25 Jan 2021 13:01:38 -0500 (EST) From: Vivek Goyal To: qemu-devel@nongnu.org, virtio-fs@redhat.com Subject: [PATCH 2/6] libvhost-user: Use slave_mutex in all slave messages Date: Mon, 25 Jan 2021 13:01:11 -0500 Message-Id: <20210125180115.22936-3-vgoyal@redhat.com> In-Reply-To: <20210125180115.22936-1-vgoyal@redhat.com> References: <20210125180115.22936-1-vgoyal@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=vgoyal@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=63.128.21.124; envelope-from=vgoyal@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.255, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: marcandre.lureau@redhat.com, stefanha@redhat.com, dgilbert@redhat.com, vgoyal@redhat.com, mst@redhat.com Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" dev->slave_mutex needs to be taken when sending messages on slave_fd. Currently _vu_queue_notify() does not do that. Introduce a helper vu_message_slave_send_receive() which sends as well as receive response. Use this helper in all the paths which send message on slave_fd channel. Signed-off-by: Vivek Goyal Reviewed-by: Greg Kurz --- subprojects/libvhost-user/libvhost-user.c | 50 ++++++++++++----------- 1 file changed, 27 insertions(+), 23 deletions(-) diff --git a/subprojects/libvhost-user/libvhost-user.c b/subprojects/libvhost-user/libvhost-user.c index 4cf4aef63d..7a56c56dc8 100644 --- a/subprojects/libvhost-user/libvhost-user.c +++ b/subprojects/libvhost-user/libvhost-user.c @@ -403,7 +403,7 @@ vu_send_reply(VuDev *dev, int conn_fd, VhostUserMsg *vmsg) * Processes a reply on the slave channel. * Entered with slave_mutex held and releases it before exit. * Returns true on success. - * *payload is written on success + * *payload is written on success, if payload is not NULL. */ static bool vu_process_message_reply(VuDev *dev, const VhostUserMsg *vmsg, @@ -427,7 +427,9 @@ vu_process_message_reply(VuDev *dev, const VhostUserMsg *vmsg, goto out; } - *payload = msg_reply.payload.u64; + if (payload) { + *payload = msg_reply.payload.u64; + } result = true; out: @@ -435,6 +437,25 @@ out: return result; } +/* Returns true on success, false otherwise */ +static bool +vu_message_slave_send_receive(VuDev *dev, VhostUserMsg *vmsg, uint64_t *payload) +{ + pthread_mutex_lock(&dev->slave_mutex); + if (!vu_message_write(dev, dev->slave_fd, vmsg)) { + pthread_mutex_unlock(&dev->slave_mutex); + return false; + } + + if ((vmsg->flags & VHOST_USER_NEED_REPLY_MASK) == 0) { + pthread_mutex_unlock(&dev->slave_mutex); + return true; + } + + /* Also unlocks the slave_mutex */ + return vu_process_message_reply(dev, vmsg, payload); +} + /* Kick the log_call_fd if required. */ static void vu_log_kick(VuDev *dev) @@ -1340,16 +1361,8 @@ bool vu_set_queue_host_notifier(VuDev *dev, VuVirtq *vq, int fd, return false; } - pthread_mutex_lock(&dev->slave_mutex); - if (!vu_message_write(dev, dev->slave_fd, &vmsg)) { - pthread_mutex_unlock(&dev->slave_mutex); - return false; - } - - /* Also unlocks the slave_mutex */ - res = vu_process_message_reply(dev, &vmsg, &payload); + res = vu_message_slave_send_receive(dev, &vmsg, &payload); res = res && (payload == 0); - return res; } @@ -2395,10 +2408,7 @@ static void _vu_queue_notify(VuDev *dev, VuVirtq *vq, bool sync) vmsg.flags |= VHOST_USER_NEED_REPLY_MASK; } - vu_message_write(dev, dev->slave_fd, &vmsg); - if (ack) { - vu_message_read_default(dev, dev->slave_fd, &vmsg); - } + vu_message_slave_send_receive(dev, &vmsg, NULL); return; } @@ -2942,17 +2952,11 @@ int64_t vu_fs_cache_request(VuDev *dev, VhostUserSlaveRequest req, int fd, return -EINVAL; } - pthread_mutex_lock(&dev->slave_mutex); - if (!vu_message_write(dev, dev->slave_fd, &vmsg)) { - pthread_mutex_unlock(&dev->slave_mutex); - return -EIO; - } - - /* Also unlocks the slave_mutex */ - res = vu_process_message_reply(dev, &vmsg, &payload); + res = vu_message_slave_send_receive(dev, &vmsg, &payload); if (!res) { return -EIO; } + /* * Payload is delivered as uint64_t but is actually signed for * errors.