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 8DAE9C38A2D for ; Thu, 27 Oct 2022 09:57:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235075AbiJ0J5I (ORCPT ); Thu, 27 Oct 2022 05:57:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40834 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235157AbiJ0J4l (ORCPT ); Thu, 27 Oct 2022 05:56:41 -0400 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 17324E22F9; Thu, 27 Oct 2022 02:56:10 -0700 (PDT) Received: from frapeml500008.china.huawei.com (unknown [172.18.147.226]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4Mygy925qrz67M1h; Thu, 27 Oct 2022 17:54:41 +0800 (CST) Received: from lhrpeml500003.china.huawei.com (7.191.162.67) by frapeml500008.china.huawei.com (7.182.85.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 27 Oct 2022 11:56:08 +0200 Received: from [10.195.32.169] (10.195.32.169) by lhrpeml500003.china.huawei.com (7.191.162.67) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 27 Oct 2022 10:56:07 +0100 Message-ID: <83d9dc82-ea37-4a3c-7e67-1c097f777767@huawei.com> Date: Thu, 27 Oct 2022 10:56:07 +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 RFC v3 2/7] ata: libata-scsi: Add ata_internal_queuecommand() To: Damien Le Moal , , , , , , , CC: , , , , , , References: <1666693976-181094-1-git-send-email-john.garry@huawei.com> <1666693976-181094-3-git-send-email-john.garry@huawei.com> <08fdb698-0df3-7bc8-e6af-7d13cc96acfa@opensource.wdc.com> From: John Garry In-Reply-To: <08fdb698-0df3-7bc8-e6af-7d13cc96acfa@opensource.wdc.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.195.32.169] X-ClientProxiedBy: lhrpeml100001.china.huawei.com (7.191.160.183) To lhrpeml500003.china.huawei.com (7.191.162.67) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 27/10/2022 02:45, Damien Le Moal wrote: > On 10/25/22 19:32, John Garry wrote: >> Add callback to queue reserved commands - call it "internal" as this is >> what libata uses. >> >> Also add it to the base ATA SHT. >> >> Signed-off-by: John Garry >> --- >> drivers/ata/libata-scsi.c | 14 ++++++++++++++ >> include/linux/libata.h | 5 ++++- >> 2 files changed, 18 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c >> index 30d7c90b0c35..0d6f37d80137 100644 >> --- a/drivers/ata/libata-scsi.c >> +++ b/drivers/ata/libata-scsi.c >> @@ -1118,6 +1118,20 @@ int ata_scsi_dev_config(struct scsi_device *sdev, struct ata_device *dev) >> return 0; >> } >> >> +int ata_internal_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmd) >> +{ >> + struct ata_port *ap; >> + int res; >> + >> + ap = ata_shost_to_port(shost); > > You can have this initialization together with the ap declaration. > >> + spin_lock_irq(ap->lock); >> + res = ata_sas_queuecmd(scmd, ap); >> + spin_unlock_irq(ap->lock); >> + >> + return res; >> +} >> +EXPORT_SYMBOL_GPL(ata_internal_queuecommand); > > I am officially lost here. Do not see why this function is needed... The general idea in this series is to send ATA internal commands as requests. And this function is used as the SCSI midlayer to queue reserved commands. See how it is plugged into __ATA_BASE_SHT, below. So we have this overall flow: ata_exec_internal_sg(): -> alloc request -> blk_execute_rq_nowait() ... -> scsi_queue_rq() -> sht->reserved_queuecommd() -> ata_internal_queuecommand() And then we have ata_internal_queuecommand() -> ata_sas_queuecmd() -> ata_scsi_queue_internal() -> ata_qc_issue(). Hope it makes sense. Thanks, John > >> + >> /** >> * ata_scsi_slave_config - Set SCSI device attributes >> * @sdev: SCSI device to examine >> diff --git a/include/linux/libata.h b/include/linux/libata.h >> index 8938b584520f..f09c5dca16ce 100644 >> --- a/include/linux/libata.h >> +++ b/include/linux/libata.h >> @@ -1141,6 +1141,8 @@ extern int ata_std_bios_param(struct scsi_device *sdev, >> sector_t capacity, int geom[]); >> extern void ata_scsi_unlock_native_capacity(struct scsi_device *sdev); >> extern int ata_scsi_slave_config(struct scsi_device *sdev); >> +extern int ata_internal_queuecommand(struct Scsi_Host *shost, >> + struct scsi_cmnd *scmd); >> extern void ata_scsi_slave_destroy(struct scsi_device *sdev); >> extern int ata_scsi_change_queue_depth(struct scsi_device *sdev, >> int queue_depth); >> @@ -1391,7 +1393,8 @@ extern const struct attribute_group *ata_common_sdev_groups[]; >> .slave_destroy = ata_scsi_slave_destroy, \ >> .bios_param = ata_std_bios_param, \ >> .unlock_native_capacity = ata_scsi_unlock_native_capacity,\ >> - .max_sectors = ATA_MAX_SECTORS_LBA48 >> + .max_sectors = ATA_MAX_SECTORS_LBA48,\ >> + .reserved_queuecommand = ata_internal_queuecommand >> >> #define ATA_SUBBASE_SHT(drv_name) \ >> __ATA_BASE_SHT(drv_name), \ >