From patchwork Mon May 3 15:03:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hannes Reinecke X-Patchwork-Id: 430724 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, 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 B461AC43461 for ; Mon, 3 May 2021 15:03:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 857F66127A for ; Mon, 3 May 2021 15:03:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230223AbhECPEu (ORCPT ); Mon, 3 May 2021 11:04:50 -0400 Received: from mx2.suse.de ([195.135.220.15]:40890 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230182AbhECPEk (ORCPT ); Mon, 3 May 2021 11:04:40 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 83A4BB1BC; Mon, 3 May 2021 15:03:44 +0000 (UTC) From: Hannes Reinecke To: "Martin K. Petersen" Cc: Christoph Hellwig , James Bottomley , John Garry , linux-scsi@vger.kernel.org, Hannes Reinecke Subject: [PATCH 07/18] scsi: revamp host device handling Date: Mon, 3 May 2021 17:03:22 +0200 Message-Id: <20210503150333.130310-8-hare@suse.de> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210503150333.130310-1-hare@suse.de> References: <20210503150333.130310-1-hare@suse.de> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Ensure that the host device is excluded from scanning by setting the BLIST_NOLUN flag, and avoid it being presented in sysfs. Also move the device id from using the ->this_id value as target id (which is a bit odd as it's typically is set to -1 anyway) to using ->max_channel + 1 as the channel number and '0' as the target id. With that the host device is now handled like any other scsi device, which means we can drop the scsi_put_host_dev() function and let scsi_forget_host() etc handle the deallocation. We only need to ensure that the host device is deallocated last is the driver might need it to send commands during teardown. Signed-off-by: Hannes Reinecke --- drivers/scsi/scsi_devinfo.c | 1 + drivers/scsi/scsi_scan.c | 55 +++++++++++++++++++------------------ include/scsi/scsi_host.h | 13 +++++---- 3 files changed, 37 insertions(+), 32 deletions(-) diff --git a/drivers/scsi/scsi_devinfo.c b/drivers/scsi/scsi_devinfo.c index d92cec12454c..e70d87c5342b 100644 --- a/drivers/scsi/scsi_devinfo.c +++ b/drivers/scsi/scsi_devinfo.c @@ -195,6 +195,7 @@ static struct { {"Intel", "Multi-Flex", NULL, BLIST_NO_RSOC}, {"iRiver", "iFP Mass Driver", NULL, BLIST_NOT_LOCKABLE | BLIST_INQUIRY_36}, {"LASOUND", "CDX7405", "3.10", BLIST_MAX5LUN | BLIST_SINGLELUN}, + {"LINUX", "VIRTUALLUN", NULL, BLIST_NOLUN}, {"Marvell", "Console", NULL, BLIST_SKIP_VPD_PAGES}, {"Marvell", "91xx Config", "1.01", BLIST_SKIP_VPD_PAGES}, {"MATSHITA", "PD-1", NULL, BLIST_FORCELUN | BLIST_SINGLELUN}, diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index 55fa7f7317a2..0b6753c1dd4d 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -1113,6 +1113,15 @@ static int scsi_probe_and_add_lun(struct scsi_target *starget, if (!sdev) goto out; + if (scsi_device_is_host_dev(sdev)) { + bflags = scsi_get_device_flags(sdev, + sdev->vendor, + sdev->model); + if (bflagsp) + *bflagsp = bflags; + return SCSI_SCAN_LUN_PRESENT; + } + result = kmalloc(result_len, GFP_KERNEL | ((shost->unchecked_isa_dma) ? __GFP_DMA : 0)); if (!result) @@ -1731,6 +1740,9 @@ static void scsi_sysfs_add_devices(struct Scsi_Host *shost) /* If device is already visible, skip adding it to sysfs */ if (sdev->is_visible) continue; + /* Host devices should never be visible in sysfs */ + if (scsi_device_is_host_dev(sdev)) + continue; if (!scsi_host_scan_allowed(shost) || scsi_sysfs_add_sdev(sdev) != 0) __scsi_remove_device(sdev); @@ -1895,12 +1907,16 @@ EXPORT_SYMBOL(scsi_scan_host); void scsi_forget_host(struct Scsi_Host *shost) { - struct scsi_device *sdev; + struct scsi_device *sdev, *host_sdev = NULL; unsigned long flags; restart: spin_lock_irqsave(shost->host_lock, flags); list_for_each_entry(sdev, &shost->__devices, siblings) { + if (scsi_device_is_host_dev(sdev)) { + host_sdev = sdev; + continue; + } if (sdev->sdev_state == SDEV_DEL) continue; spin_unlock_irqrestore(shost->host_lock, flags); @@ -1908,10 +1924,13 @@ void scsi_forget_host(struct Scsi_Host *shost) goto restart; } spin_unlock_irqrestore(shost->host_lock, flags); + /* Remove host device last, might be needed to send commands */ + if (host_sdev) + __scsi_remove_device(host_sdev); } /** - * scsi_get_host_dev - Create a scsi_device that points to the host adapter itself + * scsi_get_host_dev - Create a virtual scsi_device to the host adapter * @shost: Host that needs a scsi_device * * Lock status: None assumed. @@ -1919,13 +1938,12 @@ void scsi_forget_host(struct Scsi_Host *shost) * 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. + * Attach a single scsi_device to the Scsi_Host. The primary aim + * for this device is to serve as a container from which valid + * scsi commands can be allocated from. Each scsi command will carry + * an unused/free command tag, which then can be used by the LLDD to + * send internal or passthrough commands without having to find a + * valid command tag internally. */ struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost) { @@ -1935,7 +1953,8 @@ struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost) mutex_lock(&shost->scan_mutex); if (!scsi_host_scan_allowed(shost)) goto out; - starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id); + starget = scsi_alloc_target(&shost->shost_gendev, + shost->max_channel + 1, 0); if (!starget) goto out; @@ -1953,22 +1972,6 @@ struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost) } 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); - /** * scsi_device_is_host_dev - Check if a scsi device is a host device * @sdev: SCSI device to test diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h index f492e9034a62..f115150559ca 100644 --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -804,14 +804,15 @@ void scsi_host_busy_iter(struct Scsi_Host *, struct class_container; /* - * These three functions are used to allocate, free, and test for - * 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 + * These functions are used to allocate and test a pseudo device + * which will refer to the host adapter itself rather than any + * physical device. The device will be deallocated together with + * all other scsi devices, so there is no need to have a separate + * function to free it. + * This device will not show up in sysfs 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 *); +struct scsi_device *scsi_get_host_dev(struct Scsi_Host *); bool scsi_device_is_host_dev(struct scsi_device *); /*