From mboxrd@z Thu Jan 1 00:00:00 1970 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 64467C07545 for ; Wed, 25 Oct 2023 15:01:40 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qvfN9-0001Lq-Sq; Wed, 25 Oct 2023 11:00:39 -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 1qvfMt-0000rX-4I for qemu-devel@nongnu.org; Wed, 25 Oct 2023 11:00:24 -0400 Received: from smtp-out2.suse.de ([195.135.220.29]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1qvfMn-0000a1-So for qemu-devel@nongnu.org; Wed, 25 Oct 2023 11:00:20 -0400 Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 961081FF75; Wed, 25 Oct 2023 15:00:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1698246015; h=from:from:reply-to: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=4DUUUsQbiFl6tVPuKXCknahsql5mquXlXUzOg4upTJo=; b=LQpcQlBYhEWrKCFfqMYZoU0KDdQApUD3slJvePPbtSA9dvAHv5Cguqu2+7msokAfBlJeI8 ZOydW0RDgNthZGxFxjxAiryFGb37Fszri6aE+mBn1OA/ccNuq0DUY6oC3G5ltvZjlIvkzs X2ckCF7rb4v8DkL3PwRZmMdRX8LalNI= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1698246015; h=from:from:reply-to: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=4DUUUsQbiFl6tVPuKXCknahsql5mquXlXUzOg4upTJo=; b=eQSo+gINp+AWjNf/Nj62k1YCCPhyjenoCxMIAEq/iWcs2d89LzVT5jhC9ycERdp3JFcTEm T4oUVzz5SJNPlbAA== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 28366138E9; Wed, 25 Oct 2023 15:00:14 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id 2lj9OH4tOWVALAAAMHmgww (envelope-from ); Wed, 25 Oct 2023 15:00:14 +0000 From: Fabiano Rosas To: =?utf-8?Q?Daniel_P=2E_Berrang=C3=A9?= Cc: qemu-devel@nongnu.org, armbru@redhat.com, Juan Quintela , Peter Xu , Leonardo Bras , Claudio Fontana Subject: Re: [PATCH v2 19/29] migration/multifd: Add outgoing QIOChannelFile support In-Reply-To: References: <20231023203608.26370-1-farosas@suse.de> <20231023203608.26370-20-farosas@suse.de> <87o7gmeqp5.fsf@suse.de> Date: Wed, 25 Oct 2023 12:00:12 -0300 Message-ID: <877cnaeohv.fsf@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=195.135.220.29; envelope-from=farosas@suse.de; helo=smtp-out2.suse.de X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, 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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Daniel P. Berrang=C3=A9 writes: > On Wed, Oct 25, 2023 at 11:12:38AM -0300, Fabiano Rosas wrote: >> Daniel P. Berrang=C3=A9 writes: >>=20 >> > On Mon, Oct 23, 2023 at 05:35:58PM -0300, Fabiano Rosas wrote: >> >> Allow multifd to open file-backed channels. This will be used when >> >> enabling the fixed-ram migration stream format which expects a >> >> seekable transport. >> >>=20 >> >> The QIOChannel read and write methods will use the preadv/pwritev >> >> versions which don't update the file offset at each call so we can >> >> reuse the fd without re-opening for every channel. >> >>=20 >> >> Note that this is just setup code and multifd cannot yet make use of >> >> the file channels. >> >>=20 >> >> Signed-off-by: Fabiano Rosas >> >> --- >> >> migration/file.c | 64 +++++++++++++++++++++++++++++++++++++++++= -- >> >> migration/file.h | 10 +++++-- >> >> migration/migration.c | 2 +- >> >> migration/multifd.c | 14 ++++++++-- >> >> migration/options.c | 7 +++++ >> >> migration/options.h | 1 + >> >> 6 files changed, 90 insertions(+), 8 deletions(-) >> >>=20 >> >> diff --git a/migration/file.c b/migration/file.c >> >> index cf5b1bf365..93b9b7bf5d 100644 >> >> --- a/migration/file.c >> >> +++ b/migration/file.c >> >> @@ -17,6 +17,12 @@ >> > >> >> +void file_send_channel_create(QIOTaskFunc f, void *data) >> >> +{ >> >> + QIOChannelFile *ioc; >> >> + QIOTask *task; >> >> + Error *errp =3D NULL; >> >> + >> >> + ioc =3D qio_channel_file_new_path(outgoing_args.fname, >> >> + outgoing_args.flags, >> >> + outgoing_args.mode, &errp); >> >> + if (!ioc) { >> >> + file_migration_cancel(errp); >> >> + return; >> >> + } >> >> + >> >> + task =3D qio_task_new(OBJECT(ioc), f, (gpointer)data, NULL); >> >> + qio_task_run_in_thread(task, qio_channel_file_connect_worker, >> >> + (gpointer)data, NULL, NULL); >> >> +} >> >> + >> >> void file_start_outgoing_migration(MigrationState *s, const char *fi= lespec, >> >> Error **errp) >> >> { >> >> - g_autofree char *filename =3D g_strdup(filespec); >> >> g_autoptr(QIOChannelFile) fioc =3D NULL; >> >> + g_autofree char *filename =3D g_strdup(filespec); >> >> uint64_t offset =3D 0; >> >> QIOChannel *ioc; >> >> + int flags =3D O_CREAT | O_TRUNC | O_WRONLY; >> >> + mode_t mode =3D 0660; >> >>=20=20 >> >> trace_migration_file_outgoing(filename); >> >>=20=20 >> >> @@ -50,12 +105,15 @@ void file_start_outgoing_migration(MigrationStat= e *s, const char *filespec, >> >> return; >> >> } >> >>=20=20 >> >> - fioc =3D qio_channel_file_new_path(filename, O_CREAT | O_WRONLY = | O_TRUNC, >> >> - 0600, errp); >>=20 >> By the way, we're experimenting with add-fd to flesh out the interface >> with libvirt and I see that the flags here can conflict with the flags >> set on the fd passed through `virsh --pass-fd ...` due to this at >> monitor_fdset_dup_fd_add(): >>=20 >> if ((flags & O_ACCMODE) =3D=3D (mon_fd_flags & O_ACCMODE)) { >> fd =3D mon_fdset_fd->fd; >> break; >> } >>=20 >> We're requiring the O_RDONLY, O_WRONLY, O_RDWR flags defined here to >> match the fdset passed into QEMU. Should we just sync the code of the >> two projects to use the same flags? That feels a little clumsy to me. > > Is there a reason for libvirt to have set O_RDONLY for a file used > for outgoing migration ? I can't recall off-hand. > The flags need to match exactly, so either libvirt or QEMU could in the future decide to use O_RDWR. Then we'd have a compatibility problem when passing the fds around.