From patchwork Thu Oct 12 09:53:13 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vladimir Sementsov-Ogievskiy X-Patchwork-Id: 824747 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3yCR5d4gSgz9t2l for ; Thu, 12 Oct 2017 20:54:29 +1100 (AEDT) Received: from localhost ([::1]:44513 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e2aCB-0001Jb-3B for incoming@patchwork.ozlabs.org; Thu, 12 Oct 2017 05:54:27 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35439) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e2aBI-0001FU-4o for qemu-devel@nongnu.org; Thu, 12 Oct 2017 05:53:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e2aBF-0000HW-Dj for qemu-devel@nongnu.org; Thu, 12 Oct 2017 05:53:32 -0400 Received: from mailhub.sw.ru ([195.214.232.25]:15318 helo=relay.sw.ru) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1e2aBF-0000DX-1M for qemu-devel@nongnu.org; Thu, 12 Oct 2017 05:53:29 -0400 Received: from kvm.sw.ru (msk-vpn.virtuozzo.com [195.214.232.6]) by relay.sw.ru (8.13.4/8.13.4) with ESMTP id v9C9rJVn025088; Thu, 12 Oct 2017 12:53:21 +0300 (MSK) From: Vladimir Sementsov-Ogievskiy To: qemu-block@nongnu.org, qemu-devel@nongnu.org Date: Thu, 12 Oct 2017 12:53:13 +0300 Message-Id: <20171012095319.136610-8-vsementsov@virtuozzo.com> X-Mailer: git-send-email 2.11.1 In-Reply-To: <20171012095319.136610-1-vsementsov@virtuozzo.com> References: <20171012095319.136610-1-vsementsov@virtuozzo.com> X-detected-operating-system: by eggs.gnu.org: OpenBSD 3.x [fuzzy] X-Received-From: 195.214.232.25 Subject: [Qemu-devel] [PATCH v3 07/13] nbd-server: simplify reply transmission X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, vsementsov@virtuozzo.com, mreitz@redhat.com, den@openvz.org, pbonzini@redhat.com Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Send qiov via qio_channel_writev_all instead of calling nbd_write twice with a cork. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Eric Blake --- nbd/server.c | 50 ++++++++++++++++++++++++-------------------------- 1 file changed, 24 insertions(+), 26 deletions(-) diff --git a/nbd/server.c b/nbd/server.c index afc127bbd9..c1bbe8d2d1 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -1188,6 +1188,23 @@ void nbd_export_close_all(void) } } +static int coroutine_fn nbd_co_send_iov(NBDClient *client, struct iovec *iov, + unsigned niov, Error **errp) +{ + int ret; + + g_assert(qemu_in_coroutine()); + qemu_co_mutex_lock(&client->send_lock); + client->send_coroutine = qemu_coroutine_self(); + + ret = qio_channel_writev_all(client->ioc, iov, niov, errp) < 0 ? -EIO : 0; + + client->send_coroutine = NULL; + qemu_co_mutex_unlock(&client->send_lock); + + return ret; +} + static inline void set_be_simple_reply(NBDSimpleReply *reply, uint64_t error, uint64_t handle) { @@ -1203,36 +1220,17 @@ static int nbd_co_send_simple_reply(NBDClient *client, size_t len, Error **errp) { - NBDSimpleReply simple_reply; - int ret; - - g_assert(qemu_in_coroutine()); + NBDSimpleReply reply; + struct iovec iov[] = { + {.iov_base = &reply, .iov_len = sizeof(reply)}, + {.iov_base = data, .iov_len = len} + }; trace_nbd_co_send_simple_reply(handle, error, len); - set_be_simple_reply(&simple_reply, system_errno_to_nbd_errno(error), - handle); - - qemu_co_mutex_lock(&client->send_lock); - client->send_coroutine = qemu_coroutine_self(); - - if (!len) { - ret = nbd_write(client->ioc, &simple_reply, sizeof(simple_reply), NULL); - } else { - qio_channel_set_cork(client->ioc, true); - ret = nbd_write(client->ioc, &simple_reply, sizeof(simple_reply), NULL); - if (ret == 0) { - ret = nbd_write(client->ioc, data, len, errp); - if (ret < 0) { - ret = -EIO; - } - } - qio_channel_set_cork(client->ioc, false); - } + set_be_simple_reply(&reply, system_errno_to_nbd_errno(error), handle); - client->send_coroutine = NULL; - qemu_co_mutex_unlock(&client->send_lock); - return ret; + return nbd_co_send_iov(client, iov, len ? 2 : 1, errp); } /* nbd_co_receive_request