From patchwork Thu Oct 12 09:53:10 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: 824750 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 3yCR8j20DDz9s7c for ; Thu, 12 Oct 2017 20:57:09 +1100 (AEDT) Received: from localhost ([::1]:44526 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e2aEl-0003dS-9A for incoming@patchwork.ozlabs.org; Thu, 12 Oct 2017 05:57:07 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35440) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e2aBI-0001FV-4b 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 1e2aBE-0000Gj-V6 for qemu-devel@nongnu.org; Thu, 12 Oct 2017 05:53:32 -0400 Received: from mailhub.sw.ru ([195.214.232.25]:26996 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 1e2aBE-0000DR-Jh for qemu-devel@nongnu.org; Thu, 12 Oct 2017 05:53:28 -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 v9C9rJVk025088; 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 12:53:10 +0300 Message-Id: <20171012095319.136610-5-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 04/13] nbd/server: structurize simple reply header sending 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" Use packed structure instead of pointer arithmetics. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Eric Blake --- include/block/nbd.h | 6 ++++++ nbd/server.c | 36 ++++++++++++++---------------------- 2 files changed, 20 insertions(+), 22 deletions(-) diff --git a/include/block/nbd.h b/include/block/nbd.h index 707fd37575..49008980f4 100644 --- a/include/block/nbd.h +++ b/include/block/nbd.h @@ -63,6 +63,12 @@ struct NBDReply { }; typedef struct NBDReply NBDReply; +typedef struct NBDSimpleReply { + uint32_t magic; /* NBD_SIMPLE_REPLY_MAGIC */ + uint32_t error; + uint64_t handle; +} QEMU_PACKED NBDSimpleReply; + /* Transmission (export) flags: sent from server to client during handshake, but describe what will happen during transmission */ #define NBD_FLAG_HAS_FLAGS (1 << 0) /* Flags are there */ diff --git a/nbd/server.c b/nbd/server.c index bc7f9f0fd6..43ade30ba3 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -902,26 +902,6 @@ static int nbd_receive_request(QIOChannel *ioc, NBDRequest *request, return 0; } -static int nbd_send_reply(QIOChannel *ioc, NBDReply *reply, Error **errp) -{ - uint8_t buf[NBD_REPLY_SIZE]; - - reply->error = system_errno_to_nbd_errno(reply->error); - - trace_nbd_send_reply(reply->error, reply->handle); - - /* Reply - [ 0 .. 3] magic (NBD_SIMPLE_REPLY_MAGIC) - [ 4 .. 7] error (0 == no error) - [ 7 .. 15] handle - */ - stl_be_p(buf, NBD_SIMPLE_REPLY_MAGIC); - stl_be_p(buf + 4, reply->error); - stq_be_p(buf + 8, reply->handle); - - return nbd_write(ioc, buf, sizeof(buf), errp); -} - #define MAX_NBD_REQUESTS 16 void nbd_client_get(NBDClient *client) @@ -1208,24 +1188,36 @@ void nbd_export_close_all(void) } } +static inline void set_be_simple_reply(NBDSimpleReply *reply, uint64_t error, + uint64_t handle) +{ + stl_be_p(&reply->magic, NBD_SIMPLE_REPLY_MAGIC); + stl_be_p(&reply->error, error); + stq_be_p(&reply->handle, handle); +} + static int nbd_co_send_simple_reply(NBDRequestData *req, NBDReply *reply, int len, Error **errp) { NBDClient *client = req->client; + NBDSimpleReply simple_reply; int ret; g_assert(qemu_in_coroutine()); trace_nbd_co_send_simple_reply(reply->handle, reply->error, len); + set_be_simple_reply(&simple_reply, system_errno_to_nbd_errno(reply->error), + reply->handle); + qemu_co_mutex_lock(&client->send_lock); client->send_coroutine = qemu_coroutine_self(); if (!len) { - ret = nbd_send_reply(client->ioc, reply, errp); + ret = nbd_write(client->ioc, &simple_reply, sizeof(simple_reply), NULL); } else { qio_channel_set_cork(client->ioc, true); - ret = nbd_send_reply(client->ioc, reply, errp); + ret = nbd_write(client->ioc, &simple_reply, sizeof(simple_reply), NULL); if (ret == 0) { ret = nbd_write(client->ioc, req->data, len, errp); if (ret < 0) {