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 X-Spam-Level: X-Spam-Status: No, score=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 30151C48BE5 for ; Tue, 15 Jun 2021 20:53:50 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id AEEE661350 for ; Tue, 15 Jun 2021 20:53:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AEEE661350 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:54362 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ltG4C-0004ak-RE for qemu-devel@archiver.kernel.org; Tue, 15 Jun 2021 16:53:48 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:58148) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ltFyy-0002Mb-JB for qemu-devel@nongnu.org; Tue, 15 Jun 2021 16:48:24 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:50809) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ltFyv-00015x-F9 for qemu-devel@nongnu.org; Tue, 15 Jun 2021 16:48:24 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1623790100; 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=Zhs7WliC/s9wT00d6baGraMoKIff72akb6ljKk4x0Ig=; b=aYg4u4yHFMrdPlRBQlwuJJYSmwhAu0Lltgw5xAkVXUfGTpPOtJuvnNXR1321iGEmFjpRlK x1+610sgeQ7qr6M1acKQoHW4QJdICBd/mYEeqtjTxS6HlyBfM+htR0iEgUJuxfPylx68Eu VclOzeaB7nkNn5oeb2T/CAS1Y1izu3A= 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-393-z01qVJQlNyeDbGF0UiNsYg-1; Tue, 15 Jun 2021 16:48:19 -0400 X-MC-Unique: z01qVJQlNyeDbGF0UiNsYg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3BB58100C620; Tue, 15 Jun 2021 20:48:18 +0000 (UTC) Received: from blue.redhat.com (ovpn-114-191.phx2.redhat.com [10.3.114.191]) by smtp.corp.redhat.com (Postfix) with ESMTP id B36245D9CA; Tue, 15 Jun 2021 20:48:17 +0000 (UTC) From: Eric Blake To: qemu-devel@nongnu.org Subject: [PULL 14/34] block/nbd: bs-independent interface for nbd_co_establish_connection() Date: Tue, 15 Jun 2021 15:47:36 -0500 Message-Id: <20210615204756.281505-15-eblake@redhat.com> In-Reply-To: <20210615204756.281505-1-eblake@redhat.com> References: <20210615204756.281505-1-eblake@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eblake@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" Received-SPF: pass client-ip=216.205.24.124; envelope-from=eblake@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.197, 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: Roman Kagan , Kevin Wolf , Vladimir Sementsov-Ogievskiy , "open list:Network Block Dev..." , Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Vladimir Sementsov-Ogievskiy We are going to split connection code to a separate file. Now we are ready to give nbd_co_establish_connection() clean and bs-independent interface. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Roman Kagan Reviewed-by: Eric Blake Message-Id: <20210610100802.5888-13-vsementsov@virtuozzo.com> Signed-off-by: Eric Blake --- block/nbd.c | 50 ++++++++++++++++++++++++++++++++------------------ 1 file changed, 32 insertions(+), 18 deletions(-) diff --git a/block/nbd.c b/block/nbd.c index f2d5b47026a3..15b569a899fd 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -130,7 +130,8 @@ typedef struct BDRVNBDState { static void nbd_free_connect_thread(NBDConnectThread *thr); static int nbd_establish_connection(BlockDriverState *bs, SocketAddress *saddr, Error **errp); -static int nbd_co_establish_connection(BlockDriverState *bs, Error **errp); +static coroutine_fn QIOChannelSocket * +nbd_co_establish_connection(NBDConnectThread *thr, Error **errp); static void nbd_co_establish_connection_cancel(BlockDriverState *bs); static int nbd_client_handshake(BlockDriverState *bs, Error **errp); static void nbd_yank(void *opaque); @@ -416,22 +417,37 @@ static void *connect_thread_func(void *opaque) return NULL; } -static int coroutine_fn -nbd_co_establish_connection(BlockDriverState *bs, Error **errp) +/* + * Get a new connection in context of @thr: + * if the thread is running, wait for completion + * if the thread already succeeded in the background, and user didn't get the + * result, just return it now + * otherwise the thread is not running, so start a thread and wait for + * completion + */ +static coroutine_fn QIOChannelSocket * +nbd_co_establish_connection(NBDConnectThread *thr, Error **errp) { + QIOChannelSocket *sioc = NULL; QemuThread thread; - BDRVNBDState *s = bs->opaque; - NBDConnectThread *thr = s->connect_thread; - - assert(!s->sioc); qemu_mutex_lock(&thr->mutex); + /* + * Don't call nbd_co_establish_connection() in several coroutines in + * parallel. Only one call at once is supported. + */ + assert(!thr->wait_co); + if (!thr->running) { if (thr->sioc) { /* Previous attempt finally succeeded in background */ - goto out; + sioc = g_steal_pointer(&thr->sioc); + qemu_mutex_unlock(&thr->mutex); + + return sioc; } + thr->running = true; error_free(thr->err); thr->err = NULL; @@ -445,13 +461,12 @@ nbd_co_establish_connection(BlockDriverState *bs, Error **errp) /* * We are going to wait for connect-thread finish, but - * nbd_client_co_drain_begin() can interrupt. + * nbd_co_establish_connection_cancel() can interrupt. */ qemu_coroutine_yield(); qemu_mutex_lock(&thr->mutex); -out: if (thr->running) { /* * The connection attempt was canceled and the coroutine resumed @@ -463,17 +478,12 @@ out: } else { error_propagate(errp, thr->err); thr->err = NULL; - s->sioc = thr->sioc; - thr->sioc = NULL; - if (s->sioc) { - yank_register_function(BLOCKDEV_YANK_INSTANCE(bs->node_name), - nbd_yank, bs); - } + sioc = g_steal_pointer(&thr->sioc); } qemu_mutex_unlock(&thr->mutex); - return s->sioc ? 0 : -1; + return sioc; } /* @@ -541,11 +551,15 @@ static coroutine_fn void nbd_reconnect_attempt(BDRVNBDState *s) s->ioc = NULL; } - if (nbd_co_establish_connection(s->bs, NULL) < 0) { + s->sioc = nbd_co_establish_connection(s->connect_thread, NULL); + if (!s->sioc) { ret = -ECONNREFUSED; goto out; } + yank_register_function(BLOCKDEV_YANK_INSTANCE(s->bs->node_name), nbd_yank, + s->bs); + bdrv_dec_in_flight(s->bs); ret = nbd_client_handshake(s->bs, NULL); -- 2.31.1