From patchwork Thu Aug 27 12:41:18 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hannes Reinecke X-Patchwork-Id: 7084271 Return-Path: X-Original-To: patchwork-linux-scsi@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id BB24E9F1C2 for ; Thu, 27 Aug 2015 12:46:16 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id C871120625 for ; Thu, 27 Aug 2015 12:46:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BBEFF20621 for ; Thu, 27 Aug 2015 12:46:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754354AbbH0MqM (ORCPT ); Thu, 27 Aug 2015 08:46:12 -0400 Received: from mx2.suse.de ([195.135.220.15]:47965 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754054AbbH0Ml3 (ORCPT ); Thu, 27 Aug 2015 08:41:29 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id F35D7AE07; Thu, 27 Aug 2015 12:41:23 +0000 (UTC) From: Hannes Reinecke To: James Bottomley Cc: Christoph Hellwig , "Martin K. Petersen" , Bart van Assche , linux-scsi@vger.kernel.org, Hannes Reinecke Subject: [PATCH 20/23] scsi_dh_alua: Recheck state on unit attention Date: Thu, 27 Aug 2015 14:41:18 +0200 Message-Id: <1440679281-13234-21-git-send-email-hare@suse.de> X-Mailer: git-send-email 1.8.5.6 In-Reply-To: <1440679281-13234-1-git-send-email-hare@suse.de> References: <1440679281-13234-1-git-send-email-hare@suse.de> Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Spam-Status: No, score=-8.3 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When we receive a unit attention code of 'ALUA state changed' we should recheck the state, as it might be due to an implicit ALUA state transition. At the same time a workqueue item might already be queued, which should be started immediately to avoid any delays. Signed-off-by: Hannes Reinecke Reviewed-by: Ewan D. Milne --- drivers/scsi/device_handler/scsi_dh_alua.c | 48 +++++++++++++++--------------- 1 file changed, 24 insertions(+), 24 deletions(-) diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 85fd597..8717fd3 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -118,7 +118,7 @@ static char print_alua_state(int); static void alua_rtpg_work(struct work_struct *work); static void alua_stpg_work(struct work_struct *work); static void alua_qdata_work(struct work_struct *work); -static void alua_check(struct scsi_device *sdev); +static void alua_check(struct scsi_device *sdev, bool force); static void release_port_group(struct kref *kref) { @@ -423,7 +423,7 @@ static char print_alua_state(int state) } static int alua_check_sense(struct scsi_device *sdev, - struct scsi_sense_hdr *sense_hdr) + struct scsi_sense_hdr *sense_hdr) { switch (sense_hdr->sense_key) { case NOT_READY: @@ -432,36 +432,34 @@ static int alua_check_sense(struct scsi_device *sdev, * LUN Not Accessible - ALUA state transition * Kickoff worker to update internal state. */ - alua_check(sdev); - return ADD_TO_MLQUEUE; + alua_check(sdev, false); + return NEEDS_RETRY; } break; case UNIT_ATTENTION: - if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00) - /* - * Power On, Reset, or Bus Device Reset, just retry. - */ - return ADD_TO_MLQUEUE; - if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x04) - /* - * Device internal reset - */ - return ADD_TO_MLQUEUE; - if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x01) + if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00) { /* - * Mode Parameter Changed + * Power On, Reset, or Bus Device Reset. + * Might have obscured a state transition, + * so schedule a recheck. */ + alua_check(sdev, true); return ADD_TO_MLQUEUE; - if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x06) + } + if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x06) { /* * ALUA state changed */ + alua_check(sdev, true); return ADD_TO_MLQUEUE; - if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x07) + } + if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x07) { /* * Implicit ALUA state transition failed */ + alua_check(sdev, true); return ADD_TO_MLQUEUE; + } break; } @@ -811,7 +809,7 @@ static void alua_qdata_work(struct work_struct *work) static void alua_rtpg_queue(struct alua_port_group *pg, struct scsi_device *sdev, - struct alua_queue_data *qdata) + struct alua_queue_data *qdata, bool force) { int start_queue = 0; unsigned long flags; @@ -832,7 +830,9 @@ static void alua_rtpg_queue(struct alua_port_group *pg, pg->rtpg_sdev = sdev; scsi_device_get(sdev); start_queue = 1; - } + } else if (!(pg->flags & ALUA_PG_RUN_RTPG) && force) + start_queue = 1; + spin_unlock_irqrestore(&pg->rtpg_lock, flags); if (start_queue) @@ -873,7 +873,7 @@ static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h) mutex_unlock(&h->init_mutex); if (pg) { pg->expiry = 0; - alua_rtpg_queue(pg, sdev, NULL); + alua_rtpg_queue(pg, sdev, NULL, true); kref_put(&pg->kref, release_port_group); } return error; @@ -982,7 +982,7 @@ static int alua_activate(struct scsi_device *sdev, pg->flags |= ALUA_OPTIMIZE_STPG; spin_unlock_irqrestore(&pg->rtpg_lock, flags); } - alua_rtpg_queue(pg, sdev, qdata); + alua_rtpg_queue(pg, sdev, qdata, true); kref_put(&pg->kref, release_port_group); out: if (fn) @@ -996,7 +996,7 @@ out: * * Check the device status */ -static void alua_check(struct scsi_device *sdev) +static void alua_check(struct scsi_device *sdev, bool force) { struct alua_dh_data *h = sdev->handler_data; struct alua_port_group *pg; @@ -1009,7 +1009,7 @@ static void alua_check(struct scsi_device *sdev) } kref_get(&pg->kref); rcu_read_unlock(); - alua_rtpg_queue(pg, sdev, NULL); + alua_rtpg_queue(pg, sdev, NULL, force); kref_put(&pg->kref, release_port_group); rcu_read_unlock(); }