From patchwork Fri Sep 1 09:41:16 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wenchao Hao X-Patchwork-Id: 13372338 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 B0FCCCA0FE6 for ; Fri, 1 Sep 2023 09:42:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348972AbjIAJm2 (ORCPT ); Fri, 1 Sep 2023 05:42:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55834 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348927AbjIAJmM (ORCPT ); Fri, 1 Sep 2023 05:42:12 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 185B210D5; Fri, 1 Sep 2023 02:41:59 -0700 (PDT) Received: from kwepemm600012.china.huawei.com (unknown [172.30.72.57]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4RcXyf1dbTzNmJ3; Fri, 1 Sep 2023 17:38:18 +0800 (CST) Received: from build.huawei.com (10.175.101.6) by kwepemm600012.china.huawei.com (7.193.23.74) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Fri, 1 Sep 2023 17:41:55 +0800 From: Wenchao Hao To: "James E . J . Bottomley" , "Martin K . Petersen" , CC: Hannes Reinecke , , , , Wenchao Hao Subject: [RFC PATCH v2 08/19] scsi: scsi_error: Add a general LUN based error handler Date: Fri, 1 Sep 2023 17:41:16 +0800 Message-ID: <20230901094127.2010873-9-haowenchao2@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20230901094127.2010873-1-haowenchao2@huawei.com> References: <20230901094127.2010873-1-haowenchao2@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.101.6] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To kwepemm600012.china.huawei.com (7.193.23.74) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Add a general LUN based error handler which can be used by drivers directly. This error handler implements an scsi_device_eh, when handling error commands, it would call helper function scsi_sdev_eh() added before to try recover error commands. The behavior if scsi_sdev_eh() can not recover all error commands depends on fallback flag, which is initialized when scsi_device is allocated. If fallback is set, it would fallback to further error recover strategy like old host based error handle; else it would mark this scsi device offline and flush all error commands. To using this error handler, drivers should call scsi_device_setup_eh() in its slave_alloc() to setup it's LUN based error handler; call scsi_device_clear_eh() in its slave_destroy() to clear LUN based error handler. Signed-off-by: Wenchao Hao --- drivers/scsi/scsi_error.c | 170 ++++++++++++++++++++++++++++++++++++++ include/scsi/scsi_eh.h | 2 + 2 files changed, 172 insertions(+) diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c index f24f081fc637..b17bf1dea799 100644 --- a/drivers/scsi/scsi_error.c +++ b/drivers/scsi/scsi_error.c @@ -2759,3 +2759,173 @@ bool scsi_get_sense_info_fld(const u8 *sense_buffer, int sb_len, } } EXPORT_SYMBOL(scsi_get_sense_info_fld); + +struct scsi_lun_eh { + spinlock_t eh_lock; + unsigned int eh_num; + struct list_head eh_cmd_q; + struct scsi_device *sdev; + struct work_struct eh_handle_work; + unsigned int fallback:1; /* If fallback to further */ + /* recovery on failure */ +}; + +/* + * error handle strategy based on LUN, following steps + * is applied to recovery error commands in list: + * check sense data + * send start unit + * reset lun + * if there are still error commands, it would fallback to + * target based or host based error handle for further recovery. + */ +static void sdev_eh_work(struct work_struct *work) +{ + unsigned long flags; + struct scsi_lun_eh *luneh = + container_of(work, struct scsi_lun_eh, eh_handle_work); + struct scsi_device *sdev = luneh->sdev; + struct scsi_device_eh *eh = sdev->eh; + struct Scsi_Host *shost = sdev->host; + struct scsi_cmnd *scmd, *next; + LIST_HEAD(eh_work_q); + LIST_HEAD(eh_done_q); + + spin_lock_irqsave(&luneh->eh_lock, flags); + list_splice_init(&luneh->eh_cmd_q, &eh_work_q); + spin_unlock_irqrestore(&luneh->eh_lock, flags); + + if (scsi_sdev_eh(sdev, &eh_work_q, &eh_done_q)) + goto out_flush_done; + + if (!luneh->fallback) { + list_for_each_entry_safe(scmd, next, &eh_work_q, eh_entry) + scsi_eh_finish_cmd(scmd, &eh_done_q); + + sdev_printk(KERN_INFO, sdev, "%s:luneh: Device offlined - " + "not ready after error recovery\n", current->comm); + + mutex_lock(&sdev->state_mutex); + scsi_device_set_state(sdev, SDEV_OFFLINE); + mutex_unlock(&sdev->state_mutex); + + goto out_flush_done; + } + + /* + * fallback to target or host based error handle + */ + SCSI_LOG_ERROR_RECOVERY(2, sdev_printk(KERN_INFO, sdev, + "%s:luneh fallback to further recovery\n", current->comm)); + list_for_each_entry_safe(scmd, next, &eh_work_q, eh_entry) { + list_del_init(&scmd->eh_entry); + + if (scsi_host_in_recovery(shost) || + __scsi_eh_scmd_add_starget(scmd)) + __scsi_eh_scmd_add(scmd); + } + + eh->get_sense_done = 1; + eh->stu_done = 1; + eh->reset_done = 1; + +out_flush_done: + scsi_eh_flush_done_q(&eh_done_q); + spin_lock_irqsave(&luneh->eh_lock, flags); + luneh->eh_num = 0; + spin_unlock_irqrestore(&luneh->eh_lock, flags); +} +static void sdev_eh_add_cmnd(struct scsi_cmnd *scmd) +{ + unsigned long flags; + struct scsi_lun_eh *luneh; + struct scsi_device *sdev = scmd->device; + + luneh = (struct scsi_lun_eh *)sdev->eh->driver_data; + + spin_lock_irqsave(&luneh->eh_lock, flags); + list_add_tail(&scmd->eh_entry, &luneh->eh_cmd_q); + luneh->eh_num++; + spin_unlock_irqrestore(&luneh->eh_lock, flags); +} +static int sdev_eh_is_busy(struct scsi_device *sdev) +{ + int ret = 0; + unsigned long flags; + struct scsi_lun_eh *luneh; + + if (!sdev->eh) + return 0; + + luneh = (struct scsi_lun_eh *)sdev->eh->driver_data; + + spin_lock_irqsave(&luneh->eh_lock, flags); + ret = luneh->eh_num; + spin_unlock_irqrestore(&luneh->eh_lock, flags); + + return ret; +} +static int sdev_eh_wakeup(struct scsi_device *sdev) +{ + unsigned long flags; + unsigned int nr_error; + unsigned int nr_busy; + struct scsi_lun_eh *luneh; + + luneh = (struct scsi_lun_eh *)sdev->eh->driver_data; + + spin_lock_irqsave(&luneh->eh_lock, flags); + nr_error = luneh->eh_num; + spin_unlock_irqrestore(&luneh->eh_lock, flags); + + nr_busy = scsi_device_busy(sdev); + + if (!nr_error || nr_busy != nr_error) { + SCSI_LOG_ERROR_RECOVERY(5, sdev_printk(KERN_INFO, sdev, + "%s:luneh: do not wake up, busy/error: %d/%d\n", + current->comm, nr_busy, nr_error)); + return 0; + } + + SCSI_LOG_ERROR_RECOVERY(2, sdev_printk(KERN_INFO, sdev, + "%s:luneh: waking up, busy/error: %d/%d\n", + current->comm, nr_busy, nr_error)); + + return schedule_work(&luneh->eh_handle_work); +} + +int scsi_device_setup_eh(struct scsi_device *sdev, int fallback) +{ + struct scsi_device_eh *eh; + struct scsi_lun_eh *luneh; + + eh = kzalloc(sizeof(struct scsi_device_eh) + sizeof(struct scsi_lun_eh), + GFP_KERNEL); + if (!eh) { + sdev_printk(KERN_ERR, sdev, "failed to setup error handle\n"); + return -ENOMEM; + } + luneh = (struct scsi_lun_eh *)eh->driver_data; + + eh->add_cmnd = sdev_eh_add_cmnd; + eh->is_busy = sdev_eh_is_busy; + eh->wakeup = sdev_eh_wakeup; + + luneh->fallback = fallback; + luneh->sdev = sdev; + spin_lock_init(&luneh->eh_lock); + INIT_LIST_HEAD(&luneh->eh_cmd_q); + INIT_WORK(&luneh->eh_handle_work, sdev_eh_work); + + sdev->eh = eh; + + return 0; +} +EXPORT_SYMBOL_GPL(scsi_device_setup_eh); + +void scsi_device_clear_eh(struct scsi_device *sdev) +{ + kfree(sdev->eh); + sdev->eh = NULL; +} +EXPORT_SYMBOL_GPL(scsi_device_clear_eh); diff --git a/include/scsi/scsi_eh.h b/include/scsi/scsi_eh.h index 5ce791063baf..89b471aa484f 100644 --- a/include/scsi/scsi_eh.h +++ b/include/scsi/scsi_eh.h @@ -20,6 +20,8 @@ extern bool scsi_command_normalize_sense(const struct scsi_cmnd *cmd, extern enum scsi_disposition scsi_check_sense(struct scsi_cmnd *); extern int scsi_sdev_eh(struct scsi_device *sdev, struct list_head *workq, struct list_head *doneq); +extern int scsi_device_setup_eh(struct scsi_device *sdev, int fallback); +extern void scsi_device_clear_eh(struct scsi_device *sdev); static inline bool scsi_sense_is_deferred(const struct scsi_sense_hdr *sshdr) {