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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D8793C433FE for ; Wed, 6 Apr 2022 10:47:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236946AbiDFKtq (ORCPT ); Wed, 6 Apr 2022 06:49:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40222 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1359019AbiDFKsX (ORCPT ); Wed, 6 Apr 2022 06:48:23 -0400 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4FF07505E5F; Wed, 6 Apr 2022 00:12:13 -0700 (PDT) Received: from fraeml744-chm.china.huawei.com (unknown [172.18.147.206]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4KYFym3T3lz683hj; Wed, 6 Apr 2022 15:10:24 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml744-chm.china.huawei.com (10.206.15.225) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Wed, 6 Apr 2022 09:12:10 +0200 Received: from [10.47.80.129] (10.47.80.129) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Wed, 6 Apr 2022 08:12:09 +0100 Message-ID: Date: Wed, 6 Apr 2022 08:12:08 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.6.1 Subject: Re: [PATCH v2 1/2] libata: Use scsi cmnd budget token for qc tag for SAS host To: Damien Le Moal , CC: , , , References: <1649083990-207133-1-git-send-email-john.garry@huawei.com> <1649083990-207133-2-git-send-email-john.garry@huawei.com> From: John Garry In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.47.80.129] X-ClientProxiedBy: lhreml728-chm.china.huawei.com (10.201.108.79) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-ide@vger.kernel.org On 06/04/2022 02:39, Damien Le Moal wrote: > On 4/4/22 23:53, John Garry wrote: >> For attaining a qc tag for a SAS host we need to allocate a bit in >> ata_port.sas_tag_allocated bitmap. >> >> However we already have a unique tag per device in range >> [0, ATA_MAX_QUEUE) in the scsi cmnd budget token, so just use that >> instead. > > The valid range is [0, ATA_MAX_QUEUE - 1]. Tag ATA_MAX_QUEUE is > ATA_TAG_INTERNAL which is never allocated as a valid device tag but used > directly in ata_exec_internal(). But that is what I have in [0, ATA_MAX_QUEUE), which is same as [0, ATA_MAX_QUEUE - 1]. Thanks, john