From nobody Sun Sep 28 16:34:08 2025 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=quarantine dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1758282781; cv=none; d=zohomail.com; s=zohoarc; b=SynzIEItvHJn8gylIMgv8WlERUUifSt+JzX4Zd4Pa7qodxHwzEafoAMtWXA91dEurZ4yHOtBNt+Qe7xNk4hALwYlnm48mzKYIlCzJggxVy3pPSyswC5yxGrmFhK9Lgtd9Hfac2qXJ9W21W9qZZb+u3qtSnNjeymMKr9vTEVv6iY= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1758282781; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:Subject:To:To:Message-Id:Reply-To; bh=kVgOQG1mOqMMrShBgYl6HdG7O1jge5gMd4Y6e+CPNqA=; b=POOPUFD0qbqBwloahnLHWO66WQwGeGMxZ5g3n6op71W9UQvH0gz7UmKPXis2wN/N42ps+mnW1Q5TH8yfnIsyb1bzvU5MichJuxfjtQjFahVPLtXauGCCYIilrZn6gKoQ41nHds7KsFdnF+JjnEEn7CNuT4dK8B+GbGxZEq7KbUQ= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass header.from= (p=quarantine dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1758282781035703.6607998295216; Fri, 19 Sep 2025 04:53:01 -0700 (PDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1uzZe3-0002EF-IV; Fri, 19 Sep 2025 07:51:19 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1uzZe2-00027z-8N for qemu-devel@nongnu.org; Fri, 19 Sep 2025 07:51:18 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1uzZdw-0000oD-TP for qemu-devel@nongnu.org; Fri, 19 Sep 2025 07:51:17 -0400 Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-33-mJWvmZtmPq-bINoxBXqtxw-1; Fri, 19 Sep 2025 07:51:03 -0400 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 90D59180035C; Fri, 19 Sep 2025 11:51:00 +0000 (UTC) Received: from toolbx.redhat.com (unknown [10.42.28.187]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 9E1781955F21; Fri, 19 Sep 2025 11:50:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1758282668; 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=kVgOQG1mOqMMrShBgYl6HdG7O1jge5gMd4Y6e+CPNqA=; b=eOSq/Wn+meKdjJdobgJyw9GPdX08GuFfp3JMvOwCZXMnjyptRi21v5nbjEw8DDw0bHZRQy alW6Mx3APs8i3sZjiZLbeKVlbVhFmabwfYN7/5WLCJA7Qjfc5FlJr075YrI7vXcLr9N87f fENpMnSihD9z3bDr8N7EdzXTTUMrfTo= X-MC-Unique: mJWvmZtmPq-bINoxBXqtxw-1 X-Mimecast-MFC-AGG-ID: mJWvmZtmPq-bINoxBXqtxw_1758282661 From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= To: qemu-devel@nongnu.org Cc: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , Jagannathan Raman , Zhao Liu , Eric Blake , Stefan Hajnoczi , "Michael S. Tsirkin" , Hanna Reitz , Gustavo Romero , Thanos Makatos , =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= , Darren Kenny , Stefano Garzarella , Kevin Wolf , Fabiano Rosas , qemu-block@nongnu.org, Peter Xu , Laurent Vivier , Jason Wang , Elena Ufimtseva , John Levon , Fam Zheng , Alexander Bulekov , Stefan Weil , Gerd Hoffmann , Coiby Xu , =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= , Qiuhao Li , Michael Roth , Vladimir Sementsov-Ogievskiy , Paolo Bonzini , Bandan Das , Kostiantyn Kostiuk , Hailiang Zhang Subject: [PULL 03/16] io/channel: document how qio_channel_readv_full() handles fds Date: Fri, 19 Sep 2025 12:50:04 +0100 Message-ID: <20250919115017.1536203-4-berrange@redhat.com> In-Reply-To: <20250919115017.1536203-1-berrange@redhat.com> References: <20250919115017.1536203-1-berrange@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.129.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.105, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_PASS=-0.001, T_SPF_TEMPERROR=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: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @redhat.com) X-ZM-MESSAGEID: 1758282781841116600 From: Vladimir Sementsov-Ogievskiy The only realization, which may have incoming fds is qio_channel_socket_readv() (in io/channel-socket.c). qio_channel_socket_readv() do call (through qio_channel_socket_copy_fds()) qemu_socket_set_block() and qemu_set_cloexec() for each fd. Also, qio_channel_socket_copy_fds() is called at the end of qio_channel_socket_readv(), on success path. Acked-by: Peter Xu Reviewed-by: Daniel P. Berrang=C3=A9 Signed-off-by: Vladimir Sementsov-Ogievskiy Signed-off-by: Daniel P. Berrang=C3=A9 --- include/io/channel.h | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/include/io/channel.h b/include/io/channel.h index 12266256a8..c7f64506f7 100644 --- a/include/io/channel.h +++ b/include/io/channel.h @@ -118,6 +118,15 @@ struct QIOChannelClass { size_t nfds, int flags, Error **errp); + + /* + * The io_readv handler must guarantee that all + * incoming fds are set BLOCKING (unless + * QIO_CHANNEL_READ_FLAG_FD_PRESERVE_BLOCKING flag is set) and + * CLOEXEC (if available). + * @fds and @nfds are set only on success path, and untouched + * in case of errors. + */ ssize_t (*io_readv)(QIOChannel *ioc, const struct iovec *iov, size_t niov, @@ -125,6 +134,7 @@ struct QIOChannelClass { size_t *nfds, int flags, Error **errp); + int (*io_close)(QIOChannel *ioc, Error **errp); GSource * (*io_create_watch)(QIOChannel *ioc, @@ -235,6 +245,13 @@ void qio_channel_set_name(QIOChannel *ioc, * was allocated. It is the callers responsibility * to call close() on each file descriptor and to * call g_free() on the array pointer in @fds. + * @fds allocated and set (and @nfds is set too) + * _only_ on success path. These parameters are + * untouched in case of errors. + * qio_channel_readv_full() guarantees that all + * incoming fds are set BLOCKING (unless + * QIO_CHANNEL_READ_FLAG_FD_PRESERVE_BLOCKING flag + * is set) and CLOEXEC (if available). * * It is an error to pass a non-NULL @fds parameter * unless qio_channel_has_feature() returns a true --=20 2.50.1