From patchwork Sun Mar 28 10:25:28 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Kepplinger X-Patchwork-Id: 12168891 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=-13.8 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 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 122A7C433DB for ; Sun, 28 Mar 2021 10:26:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CAC5C60234 for ; Sun, 28 Mar 2021 10:26:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231128AbhC1K0G (ORCPT ); Sun, 28 Mar 2021 06:26:06 -0400 Received: from comms.puri.sm ([159.203.221.185]:56142 "EHLO comms.puri.sm" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230092AbhC1KZt (ORCPT ); Sun, 28 Mar 2021 06:25:49 -0400 Received: from localhost (localhost [127.0.0.1]) by comms.puri.sm (Postfix) with ESMTP id 71432E01F7; Sun, 28 Mar 2021 03:25:49 -0700 (PDT) Received: from comms.puri.sm ([127.0.0.1]) by localhost (comms.puri.sm [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id xLhsW1HiZtqA; Sun, 28 Mar 2021 03:25:48 -0700 (PDT) From: Martin Kepplinger To: martin.kepplinger@puri.sm Cc: bvanassche@acm.org, jejb@linux.ibm.com, linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, linux-pm@vger.kernel.org, martin.petersen@oracle.com, stern@rowland.harvard.edu Subject: [PATCH v3 1/4] scsi: add expecting_media_change flag to error path Date: Sun, 28 Mar 2021 12:25:28 +0200 Message-Id: <20210328102531.1114535-2-martin.kepplinger@puri.sm> In-Reply-To: <20210328102531.1114535-1-martin.kepplinger@puri.sm> References: <20210328102531.1114535-1-martin.kepplinger@puri.sm> Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org SD Cardreaders (especially) sometimes lose the state during suspend and deliver a "media changed" unit attention when really only a (runtime) suspend/resume cycle has been done. For such devices, I/O fails when runtime PM is enabled, see below. That's the motivation to add this flag. If set by a driver the one following MEDIA CHANGE unit attention will be ignored. Signed-off-by: Martin Kepplinger --- drivers/scsi/scsi_error.c | 36 +++++++++++++++++++++++++++++++----- include/scsi/scsi_device.h | 1 + 2 files changed, 32 insertions(+), 5 deletions(-) diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c index 08c06c56331c..c62915d34ba4 100644 --- a/drivers/scsi/scsi_error.c +++ b/drivers/scsi/scsi_error.c @@ -585,6 +585,18 @@ int scsi_check_sense(struct scsi_cmnd *scmd) return NEEDS_RETRY; } } + if (scmd->device->expecting_media_change) { + if (sshdr.asc == 0x28 && sshdr.ascq == 0x00) { + /* + * clear the expecting_media_change in + * scsi_decide_disposition() because we + * need to catch possible "fail fast" overrides + * that block readahead can cause. + */ + return NEEDS_RETRY; + } + } + /* * we might also expect a cc/ua if another LUN on the target * reported a UA with an ASC/ASCQ of 3F 0E - @@ -1977,14 +1989,28 @@ int scsi_decide_disposition(struct scsi_cmnd *scmd) * the request was not marked fast fail. Note that above, * even if the request is marked fast fail, we still requeue * for queue congestion conditions (QUEUE_FULL or BUSY) */ - if (scsi_cmd_retry_allowed(scmd) && !scsi_noretry_cmd(scmd)) { - return NEEDS_RETRY; - } else { - /* - * no more retries - report this one back to upper level. + if (scsi_cmd_retry_allowed(scmd)) { + /* but scsi_noretry_cmd() cannot override the + * expecting_media_change flag. */ + if (!scsi_noretry_cmd(scmd) || + scmd->device->expecting_media_change) { + scmd->device->expecting_media_change = 0; + return NEEDS_RETRY; + } + + /* Not marked fail fast, or marked but not expected. + * Clear the flag too because it's meant for the + * next UA only. + */ + scmd->device->expecting_media_change = 0; return SUCCESS; } + + /* + * no more retries - report this one back to upper level. + */ + return SUCCESS; } static void eh_lock_door_done(struct request *req, blk_status_t status) diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index 05c7c320ef32..926b42ce1dc4 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -171,6 +171,7 @@ struct scsi_device { * this device */ unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN * because we did a bus reset. */ + unsigned expecting_media_change:1; /* Expecting "media changed" UA */ unsigned use_10_for_rw:1; /* first try 10-byte read / write */ unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */ unsigned set_dbd_for_ms:1; /* Set "DBD" field in mode sense */