From patchwork Tue Jul 12 08:24:36 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oliver Neukum X-Patchwork-Id: 9224775 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id DA3F360868 for ; Tue, 12 Jul 2016 08:24:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C9FD127F17 for ; Tue, 12 Jul 2016 08:24:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id BEA0327EED; Tue, 12 Jul 2016 08:24:53 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 175AD27E63 for ; Tue, 12 Jul 2016 08:24:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752297AbcGLIYr (ORCPT ); Tue, 12 Jul 2016 04:24:47 -0400 Received: from mx2.suse.de ([195.135.220.15]:49636 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751984AbcGLIYp (ORCPT ); Tue, 12 Jul 2016 04:24:45 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 1BE69AC32; Tue, 12 Jul 2016 08:24:42 +0000 (UTC) From: Oliver Neukum To: linux-usb@vger.kernel.org, stern@rowland.harvard.edu, linux-scsi@vger.kernel.org, usb-storage@lists.one-eyed-alien.net, gregKH@linuxfoundation.org, mdharm-usb@one-eyed-alien.net Cc: Oliver Neukum Subject: [PATCH] scsi: introduce a quirk for false cache reporting Date: Tue, 12 Jul 2016 10:24:36 +0200 Message-Id: <1468311876-4132-1-git-send-email-oneukum@suse.com> X-Mailer: git-send-email 2.1.4 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Some SATA to USB bridges fail to cooperate with some drives resulting in no cache being present being reported to the host. That causes the host to skip sending a command to synchronize caches. That causes data loss when the drive is powered down. Signed-off-by: Oliver Neukum Reviewed-by: Johannes Thumshirn --- Documentation/kernel-parameters.txt | 2 ++ drivers/scsi/sd.c | 6 +++--- drivers/usb/storage/scsiglue.c | 4 ++++ drivers/usb/storage/usb.c | 6 +++++- include/linux/usb_usual.h | 2 ++ include/scsi/scsi_device.h | 1 + 6 files changed, 17 insertions(+), 4 deletions(-) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 82b42c9..c8c682e 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -4182,6 +4182,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted. u = IGNORE_UAS (don't bind to the uas driver); w = NO_WP_DETECT (don't test whether the medium is write-protected). + y = ALWAYS_SYNC (issue a SYNCHRONIZE_CACHE + even if the device claims no cache) Example: quirks=0419:aaf5:rl,0421:0433:rc user_debug= [KNL,ARM] diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 60bff78..3e8a6f1 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -139,7 +139,7 @@ static void sd_set_flush_flag(struct scsi_disk *sdkp) { bool wc = false, fua = false; - if (sdkp->WCE) { + if (sdkp->WCE || sdkp->device->always_sync) { wc = true; if (sdkp->DPOFUA) fua = true; @@ -3228,7 +3228,7 @@ static void sd_shutdown(struct device *dev) if (pm_runtime_suspended(dev)) return; - if (sdkp->WCE && sdkp->media_present) { + if ((sdkp->WCE || sdkp->device->always_sync) && sdkp->media_present) { sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n"); sd_sync_cache(sdkp); } @@ -3247,7 +3247,7 @@ static int sd_suspend_common(struct device *dev, bool ignore_stop_errors) if (!sdkp) /* E.g.: runtime suspend following sd_remove() */ return 0; - if (sdkp->WCE && sdkp->media_present) { + if ((sdkp->WCE || sdkp->device->always_sync) && sdkp->media_present) { sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n"); ret = sd_sync_cache(sdkp); if (ret) { diff --git a/drivers/usb/storage/scsiglue.c b/drivers/usb/storage/scsiglue.c index 33eb923..43e76ae 100644 --- a/drivers/usb/storage/scsiglue.c +++ b/drivers/usb/storage/scsiglue.c @@ -296,6 +296,10 @@ static int slave_configure(struct scsi_device *sdev) if (us->fflags & US_FL_BROKEN_FUA) sdev->broken_fua = 1; + /* Some even totally fail to indicate a cache */ + if (us->fflags & US_FL_ALWAYS_SYNC) + sdev->always_sync = 1; + } else { /* diff --git a/drivers/usb/storage/usb.c b/drivers/usb/storage/usb.c index ef2d8cd..19255f1 100644 --- a/drivers/usb/storage/usb.c +++ b/drivers/usb/storage/usb.c @@ -498,7 +498,8 @@ void usb_stor_adjust_quirks(struct usb_device *udev, unsigned long *fflags) US_FL_NO_READ_DISC_INFO | US_FL_NO_READ_CAPACITY_16 | US_FL_INITIAL_READ10 | US_FL_WRITE_CACHE | US_FL_NO_ATA_1X | US_FL_NO_REPORT_OPCODES | - US_FL_MAX_SECTORS_240 | US_FL_NO_REPORT_LUNS); + US_FL_MAX_SECTORS_240 | US_FL_NO_REPORT_LUNS | + US_FL_ALWAYS_SYNC); p = quirks; while (*p) { @@ -581,6 +582,9 @@ void usb_stor_adjust_quirks(struct usb_device *udev, unsigned long *fflags) case 'w': f |= US_FL_NO_WP_DETECT; break; + case 'y': + f |= US_FL_ALWAYS_SYNC; + break; /* Ignore unrecognized flag characters */ } } diff --git a/include/linux/usb_usual.h b/include/linux/usb_usual.h index 245f57d..0aae1b2 100644 --- a/include/linux/usb_usual.h +++ b/include/linux/usb_usual.h @@ -81,6 +81,8 @@ /* Sets max_sectors to 240 */ \ US_FLAG(NO_REPORT_LUNS, 0x10000000) \ /* Cannot handle REPORT_LUNS */ \ + US_FLAG(ALWAYS_SYNC, 0x20000000) \ + /* lies about caching, so always sync */ \ #define US_FLAG(name, value) US_FL_##name = value , enum { US_DO_ALL_FLAGS }; diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index a6c346d..392d166 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -179,6 +179,7 @@ struct scsi_device { unsigned try_rc_10_first:1; /* Try READ_CAPACACITY_10 first */ unsigned is_visible:1; /* is the device visible in sysfs */ unsigned wce_default_on:1; /* Cache is ON by default */ + unsigned always_sync:1; /* synchronize cache in every case*/ unsigned no_dif:1; /* T10 PI (DIF) should be disabled */ unsigned broken_fua:1; /* Don't set FUA bit */ unsigned lun_in_cdb:1; /* Store LUN bits in CDB[1] */