From patchwork Wed Jul 8 09:06:15 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hannes Reinecke X-Patchwork-Id: 6743091 Return-Path: X-Original-To: patchwork-linux-scsi@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 5AFA8C05AC for ; Wed, 8 Jul 2015 09:08:51 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 7669F2071E for ; Wed, 8 Jul 2015 09:08:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6397120675 for ; Wed, 8 Jul 2015 09:08:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934883AbbGHJIa (ORCPT ); Wed, 8 Jul 2015 05:08:30 -0400 Received: from cantor2.suse.de ([195.135.220.15]:35902 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933801AbbGHJGd (ORCPT ); Wed, 8 Jul 2015 05:06:33 -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 21A1DADA2; Wed, 8 Jul 2015 09:06:25 +0000 (UTC) From: Hannes Reinecke To: James Bottomley Cc: Christoph Hellwig , linux-scsi@vger.kernel.org, "Martin K. Petersen" , Bart van Assche , Hannes Reinecke Subject: [PATCH 17/20] scsi_dh_alua: Recheck state on unit attention Date: Wed, 8 Jul 2015 11:06:15 +0200 Message-Id: <1436346378-96518-18-git-send-email-hare@suse.de> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1436346378-96518-1-git-send-email-hare@suse.de> References: <1436346378-96518-1-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=-7.6 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 --- 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 ea47d15..aa58659 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -120,7 +120,7 @@ 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) { @@ -505,7 +505,7 @@ 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: @@ -514,36 +514,34 @@ 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; } @@ -899,7 +897,7 @@ 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; @@ -920,7 +918,9 @@ 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) @@ -959,7 +959,7 @@ static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h) complete(&h->init_complete); 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 h->error; @@ -1072,7 +1072,7 @@ 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) @@ -1086,7 +1086,7 @@ 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; @@ -1096,7 +1096,7 @@ static void alua_check(struct scsi_device *sdev) if (pg) { 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); } else rcu_read_unlock();