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=-9.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 3F4D4C47404 for ; Mon, 7 Oct 2019 16:32:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 08A2B2067B for ; Mon, 7 Oct 2019 16:32:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Raq6uKl3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728528AbfJGQcC (ORCPT ); Mon, 7 Oct 2019 12:32:02 -0400 Received: from mail-wr1-f65.google.com ([209.85.221.65]:41918 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727801AbfJGQcB (ORCPT ); Mon, 7 Oct 2019 12:32:01 -0400 Received: by mail-wr1-f65.google.com with SMTP id q9so16106759wrm.8; Mon, 07 Oct 2019 09:32:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=r5sgxvl6WRaxv9ieNmw/70z/3jD9DTABC5OOXf90ftA=; b=Raq6uKl3MJ7Cw7B+KO/NR0HC5loXMtgUHwXRPzbK7dBOVRU1Y+ppZMImJwz//Ltt6o bP3W/3S5EAuMkchJMY8i5j5uDkfQ7gNEj/ogPlaCzzvxFu1N2cDckT2AO9KppcPnFDDu gGX/T9wHDpNTf09IVMUL0soTcH5YDdFZyvqAMWx9Afltt+jBpV5W5hfZ1ZaNsMe2tihV 5XXAGtpHrAyNgK+Iw6pPTFKCdtEikaVgk9OHSJMKdWyuyoa+zgDEBbxdfJoawtKg92kJ 8Y7OXu4PxJD78CAxFheiNGU/xcCzpvtB9wquX2ahWUWdyGeo734aIZBVwihiNXEeN5eM 2hvw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=r5sgxvl6WRaxv9ieNmw/70z/3jD9DTABC5OOXf90ftA=; b=Wdijzm4cdzP/wuutppOBlU1/MhIJNKClE0jK/4w4zotzHESnqAI3W2KLBA/DQQACM1 OJfkgTL84r2/4pM6X5zknc8goJWNYA3LtQUu960EsVgGsswZ5v5KYH7r475xLTZfXg7y H3Pi9EFTWL6LD3E/9qmQ22/w9nr76ua1YVaiusv4hSSY5gbi6PNI5IHxyr9nUQYIAlg0 ixT8uTUNUpnciSiWuYM4yOt3kFsr3/hbB1fhy5fhbfJS3zC4G1bcwl0UeMhZHV2dDWSn ypGVyaykwn/+BefGYhTTnWgUszY8G9wVN5lh8rZED70QQJXUF4uGdNEREbcUeswQtNT1 z37g== X-Gm-Message-State: APjAAAUC3MDP08oILWX3meTiznv8dA0i/eA5afB0iXBaq1hGuzr/jbOi Pu8dL9c4fiEBz7m6oKgoJmw8bmDwKkx1Yw== X-Google-Smtp-Source: APXvYqxOqCQKUl4DWmDllgEwqvCvElcB3G2AlfDMcqca9ZfL4BfcKrYMDbK7o4JmNZ1ejk675pOL5g== X-Received: by 2002:adf:ed85:: with SMTP id c5mr12244204wro.14.1570465919066; Mon, 07 Oct 2019 09:31:59 -0700 (PDT) Received: from localhost.localdomain (userh394.uk.uudial.com. [194.69.102.21]) by smtp.gmail.com with ESMTPSA id a9sm148524wmf.14.2019.10.07.09.31.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 07 Oct 2019 09:31:58 -0700 (PDT) From: Andrea Parri To: linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org Cc: "K . Y . Srinivasan" , Haiyang Zhang , Stephen Hemminger , Sasha Levin , Michael Kelley , Vitaly Kuznetsov , Andrea Parri Subject: [PATCH 1/2] Drivers: hv: vmbus: Introduce table of VMBus protocol versions Date: Mon, 7 Oct 2019 18:31:14 +0200 Message-Id: <20191007163115.26197-2-parri.andrea@gmail.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191007163115.26197-1-parri.andrea@gmail.com> References: <20191007163115.26197-1-parri.andrea@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-hyperv-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org The technique used to get the next VMBus version seems increasisly clumsy as the number of VMBus versions increases. Performance is not a concern since this is only done once during system boot; it's just that we'll end up with more lines of code than is really needed. As an alternative, introduce a table with the version numbers listed in order (from the most recent to the oldest). vmbus_connect() loops through the versions listed in the table until it gets an accepted connection or gets to the end of the table (invalid version). Suggested-by: Michael Kelley Signed-off-by: Andrea Parri --- drivers/hv/connection.c | 51 +++++++++++++++-------------------------- include/linux/hyperv.h | 2 -- 2 files changed, 19 insertions(+), 34 deletions(-) diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c index 6e4c015783ffc..90a32c9d79403 100644 --- a/drivers/hv/connection.c +++ b/drivers/hv/connection.c @@ -40,29 +40,19 @@ EXPORT_SYMBOL_GPL(vmbus_connection); __u32 vmbus_proto_version; EXPORT_SYMBOL_GPL(vmbus_proto_version); -static __u32 vmbus_get_next_version(__u32 current_version) -{ - switch (current_version) { - case (VERSION_WIN7): - return VERSION_WS2008; - - case (VERSION_WIN8): - return VERSION_WIN7; - - case (VERSION_WIN8_1): - return VERSION_WIN8; - - case (VERSION_WIN10): - return VERSION_WIN8_1; - - case (VERSION_WIN10_V5): - return VERSION_WIN10; - - case (VERSION_WS2008): - default: - return VERSION_INVAL; - } -} +/* + * Table of VMBus versions listed from newest to oldest; the table + * must terminate with VERSION_INVAL. + */ +__u32 vmbus_versions[] = { + VERSION_WIN10_V5, + VERSION_WIN10, + VERSION_WIN8_1, + VERSION_WIN8, + VERSION_WIN7, + VERSION_WS2008, + VERSION_INVAL +}; int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version) { @@ -169,8 +159,8 @@ int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version) */ int vmbus_connect(void) { - int ret = 0; struct vmbus_channel_msginfo *msginfo = NULL; + int i, ret = 0; __u32 version; /* Initialize the vmbus connection */ @@ -244,21 +234,18 @@ int vmbus_connect(void) * version. */ - version = VERSION_CURRENT; + for (i = 0; ; i++) { + version = vmbus_versions[i]; + if (version == VERSION_INVAL) + goto cleanup; - do { ret = vmbus_negotiate_version(msginfo, version); if (ret == -ETIMEDOUT) goto cleanup; if (vmbus_connection.conn_state == CONNECTED) break; - - version = vmbus_get_next_version(version); - } while (version != VERSION_INVAL); - - if (version == VERSION_INVAL) - goto cleanup; + } vmbus_proto_version = version; pr_info("Vmbus version:%d.%d\n", diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index b4a017093b697..7073f1eb3618c 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -194,8 +194,6 @@ static inline u32 hv_get_avail_to_write_percent( #define VERSION_INVAL -1 -#define VERSION_CURRENT VERSION_WIN10_V5 - /* Make maximum size of pipe payload of 16K */ #define MAX_PIPE_DATA_PAYLOAD (sizeof(u8) * 16384) -- 2.23.0