From patchwork Thu Mar 3 11:59:08 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sergio Lopez Pascual X-Patchwork-Id: 12767385 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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 29B6DC433F5 for ; Thu, 3 Mar 2022 12:03:21 +0000 (UTC) Received: from localhost ([::1]:53614 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nPkAa-0005tc-E4 for qemu-devel@archiver.kernel.org; Thu, 03 Mar 2022 07:02:57 -0500 Received: from eggs.gnu.org ([209.51.188.92]:36512) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nPk80-00028k-1o for qemu-devel@nongnu.org; Thu, 03 Mar 2022 07:00:16 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:31747) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nPk7y-0003No-25 for qemu-devel@nongnu.org; Thu, 03 Mar 2022 07:00:15 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1646308812; 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=KdMdqEWeBP2boGVGfeEr3E5hnozpl+T46v4UlfqVOqc=; b=GZ8BhupHxleeNJFsCOb2vMRqIhhw3t9E4ZdOrbbmdm/+xomb2dSPWUmIlNd+Kw93QWYznl sQl2Uqh90tFa+f/2FNMLHK8V1HaRLbRM8ozLQQWfGZwmRB3dk+IXn+TXsc6bTGCGwrBB8g 8AJ9z/iDCdZjB2VoS+TxpVpGr8xxDnM= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-32-_3OU1C2pOTmZ7s9ykW7b-g-1; Thu, 03 Mar 2022 07:00:09 -0500 X-MC-Unique: _3OU1C2pOTmZ7s9ykW7b-g-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6F895801DDB; Thu, 3 Mar 2022 12:00:07 +0000 (UTC) Received: from toolbox.redhat.com (unknown [10.33.37.20]) by smtp.corp.redhat.com (Postfix) with ESMTP id 97A3A842CC; Thu, 3 Mar 2022 12:00:02 +0000 (UTC) From: Sergio Lopez To: qemu-devel@nongnu.org Subject: [PATCH v3 1/4] event_notifier: add event_notifier_get_wfd() Date: Thu, 3 Mar 2022 12:59:08 +0100 Message-Id: <20220303115911.20962-2-slp@redhat.com> In-Reply-To: <20220303115911.20962-1-slp@redhat.com> References: <20220303115911.20962-1-slp@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Received-SPF: pass client-ip=170.10.133.124; envelope-from=slp@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, 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_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Elena Ufimtseva , Fam Zheng , Matthew Rosato , John G Johnson , David Hildenbrand , Eric Farman , Alex Williamson , kvm@vger.kernel.org, qemu-block@nongnu.org, "Michael S. Tsirkin" , Halil Pasic , Christian Borntraeger , vgoyal@redhat.com, Thomas Huth , Sergio Lopez , Richard Henderson , qemu-s390x@nongnu.org, Stefan Hajnoczi , Jagannathan Raman , Kevin Wolf , Cornelia Huck , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Hanna Reitz , Paolo Bonzini Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" event_notifier_get_fd(const EventNotifier *e) always returns EventNotifier's read file descriptor (rfd). This is not a problem when the EventNotifier is backed by a an eventfd, as a single file descriptor is used both for reading and triggering events (rfd == wfd). But, when EventNotifier is backed by a pipe pair, we have two file descriptors, one that can only be used for reads (rfd), and the other only for writes (wfd). There's, at least, one known situation in which we need to obtain wfd instead of rfd, which is when setting up the file that's going to be sent to the peer in vhost's SET_VRING_CALL. Add a new event_notifier_get_wfd(const EventNotifier *e) that can be used to obtain wfd where needed. Signed-off-by: Sergio Lopez --- include/qemu/event_notifier.h | 1 + util/event_notifier-posix.c | 5 +++++ 2 files changed, 6 insertions(+) diff --git a/include/qemu/event_notifier.h b/include/qemu/event_notifier.h index b79add035d..8a4ff308e1 100644 --- a/include/qemu/event_notifier.h +++ b/include/qemu/event_notifier.h @@ -38,6 +38,7 @@ int event_notifier_test_and_clear(EventNotifier *); #ifdef CONFIG_POSIX void event_notifier_init_fd(EventNotifier *, int fd); int event_notifier_get_fd(const EventNotifier *); +int event_notifier_get_wfd(const EventNotifier *); #else HANDLE event_notifier_get_handle(EventNotifier *); #endif diff --git a/util/event_notifier-posix.c b/util/event_notifier-posix.c index 8307013c5d..16294e98d4 100644 --- a/util/event_notifier-posix.c +++ b/util/event_notifier-posix.c @@ -99,6 +99,11 @@ int event_notifier_get_fd(const EventNotifier *e) return e->rfd; } +int event_notifier_get_wfd(const EventNotifier *e) +{ + return e->wfd; +} + int event_notifier_set(EventNotifier *e) { static const uint64_t value = 1;