From patchwork Thu Jun 9 10:29:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Garry X-Patchwork-Id: 581385 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 13183CCA480 for ; Thu, 9 Jun 2022 10:36:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239968AbiFIKgM (ORCPT ); Thu, 9 Jun 2022 06:36:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58414 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240164AbiFIKgH (ORCPT ); Thu, 9 Jun 2022 06:36:07 -0400 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0D29320FC7E; Thu, 9 Jun 2022 03:36:04 -0700 (PDT) Received: from fraeml737-chm.china.huawei.com (unknown [172.18.147.226]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4LJgT147GPz6885p; Thu, 9 Jun 2022 18:34:45 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml737-chm.china.huawei.com (10.206.15.218) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 9 Jun 2022 12:36:03 +0200 Received: from localhost.localdomain (10.69.192.58) 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; Thu, 9 Jun 2022 11:35:59 +0100 From: John Garry To: , , , , , , CC: , , , , , John Garry Subject: [PATCH RFC v2 02/18] scsi: core: Resurrect scsi_{get, free}_host_dev() Date: Thu, 9 Jun 2022 18:29:03 +0800 Message-ID: <1654770559-101375-3-git-send-email-john.garry@huawei.com> X-Mailer: git-send-email 2.8.1 In-Reply-To: <1654770559-101375-1-git-send-email-john.garry@huawei.com> References: <1654770559-101375-1-git-send-email-john.garry@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.69.192.58] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org This reverts commit 6bd49b1a8d43ec118c55f3aaa7577729b52bde15. Signed-off-by: John Garry --- drivers/scsi/scsi_scan.c | 57 ++++++++++++++++++++++++++++++++++++++++ include/scsi/scsi_host.h | 10 +++++++ 2 files changed, 67 insertions(+) diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index 91ac901a6682..925fe63fa370 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -1978,3 +1978,60 @@ void scsi_forget_host(struct Scsi_Host *shost) spin_unlock_irqrestore(shost->host_lock, flags); } +/** + * scsi_get_host_dev - Create a scsi_device that points to the host adapter itself + * @shost: Host that needs a scsi_device + * + * Lock status: None assumed. + * + * Returns: The scsi_device or NULL + * + * Notes: + * Attach a single scsi_device to the Scsi_Host - this should + * be made to look like a "pseudo-device" that points to the + * HA itself. + * + * Note - this device is not accessible from any high-level + * drivers (including generics), which is probably not + * optimal. We can add hooks later to attach. + */ +struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost) +{ + struct scsi_device *sdev = NULL; + struct scsi_target *starget; + + mutex_lock(&shost->scan_mutex); + if (!scsi_host_scan_allowed(shost)) + goto out; + starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id); + if (!starget) + goto out; + + sdev = scsi_alloc_sdev(starget, 0, NULL); + if (sdev) + sdev->borken = 0; + else + scsi_target_reap(starget); + put_device(&starget->dev); + out: + mutex_unlock(&shost->scan_mutex); + return sdev; +} +EXPORT_SYMBOL(scsi_get_host_dev); + +/** + * scsi_free_host_dev - Free a scsi_device that points to the host adapter itself + * @sdev: Host device to be freed + * + * Lock status: None assumed. + * + * Returns: Nothing + */ +void scsi_free_host_dev(struct scsi_device *sdev) +{ + BUG_ON(sdev->id != sdev->host->this_id); + + __scsi_remove_device(sdev); +} +EXPORT_SYMBOL(scsi_free_host_dev); + diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h index 667d889b92b5..59aef1f178f5 100644 --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -790,6 +790,16 @@ void scsi_host_busy_iter(struct Scsi_Host *, struct class_container; +/* + * These two functions are used to allocate and free a pseudo device + * which will connect to the host adapter itself rather than any + * physical device. You must deallocate when you are done with the + * thing. This physical pseudo-device isn't real and won't be available + * from any high-level drivers. + */ +extern void scsi_free_host_dev(struct scsi_device *); +extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *); + /* * DIF defines the exchange of protection information between * initiator and SBC block device.