From patchwork Sat Nov 21 00:49:19 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vishal Verma X-Patchwork-Id: 7673021 Return-Path: X-Original-To: patchwork-linux-nvdimm@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 9984CC05CA for ; Sat, 21 Nov 2015 00:49:50 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 9B2FA2055D for ; Sat, 21 Nov 2015 00:49:49 +0000 (UTC) Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A2F5220575 for ; Sat, 21 Nov 2015 00:49:48 +0000 (UTC) Received: from ml01.vlan14.01.org (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 973A91A2097; Fri, 20 Nov 2015 16:49:48 -0800 (PST) X-Original-To: linux-nvdimm@lists.01.org Delivered-To: linux-nvdimm@lists.01.org Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by ml01.01.org (Postfix) with ESMTP id 6F8D11A2097 for ; Fri, 20 Nov 2015 16:49:46 -0800 (PST) Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga103.fm.intel.com with ESMTP; 20 Nov 2015 16:49:46 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,325,1444719600"; d="scan'208";a="690970961" Received: from omniknight.lm.intel.com ([10.232.112.76]) by orsmga003.jf.intel.com with ESMTP; 20 Nov 2015 16:49:45 -0800 From: Vishal Verma To: linux-nvdimm@lists.01.org Subject: [PATCH 2/3] block: Add badblock management for gendisks Date: Fri, 20 Nov 2015 17:49:19 -0700 Message-Id: <1448066960-20119-3-git-send-email-vishal.l.verma@intel.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1448066960-20119-1-git-send-email-vishal.l.verma@intel.com> References: <1448066960-20119-1-git-send-email-vishal.l.verma@intel.com> Cc: linux-raid@vger.kernel.org, linux-scsi@vger.kernel.org, Jens Axboe , NeilBrown , linux-block@vger.kernel.org X-BeenThere: linux-nvdimm@lists.01.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: "Linux-nvdimm developer list." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" X-Spam-Status: No, score=-3.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_LOW, 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 NVDIMM devices, which can behave more like DRAM rather than block devices, may develop bad cache lines, or 'poison'. A block device exposed by the pmem driver can then consume poison via a read (or write), and cause a machine check. On platforms without machine check recovery features, this would mean a crash. The block device maintaining a runtime list of all known sectors that have poison can directly avoid this, and also provide a path forward to enable proper handling/recovery for DAX faults on such a device. Use the new badblock management interfaces to add a badblocks list to gendisks. Signed-off-by: Vishal Verma --- block/genhd.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/genhd.h | 6 +++++ 2 files changed, 70 insertions(+) diff --git a/block/genhd.c b/block/genhd.c index 0c706f3..4209c32 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -20,6 +20,7 @@ #include #include #include +#include #include "blk.h" @@ -505,6 +506,20 @@ static int exact_lock(dev_t devt, void *data) return 0; } +static void disk_alloc_badblocks(struct gendisk *disk) +{ + disk->bb = kzalloc(sizeof(disk->bb), GFP_KERNEL); + if (!disk->bb) { + pr_warn("%s: failed to allocate space for badblocks\n", + disk->disk_name); + return; + } + + if (badblocks_init(disk->bb, 1)) + pr_warn("%s: failed to initialize badblocks\n", + disk->disk_name); +} + static void register_disk(struct gendisk *disk) { struct device *ddev = disk_to_dev(disk); @@ -609,6 +624,7 @@ void add_disk(struct gendisk *disk) disk->first_minor = MINOR(devt); disk_alloc_events(disk); + disk_alloc_badblocks(disk); /* Register BDI before referencing it from bdev */ bdi = &disk->queue->backing_dev_info; @@ -657,6 +673,9 @@ void del_gendisk(struct gendisk *disk) blk_unregister_queue(disk); blk_unregister_region(disk_devt(disk), disk->minors); + badblocks_free(disk->bb); + kfree(disk->bb); + part_stat_set_all(&disk->part0, 0); disk->part0.stamp = 0; @@ -670,6 +689,48 @@ void del_gendisk(struct gendisk *disk) } EXPORT_SYMBOL(del_gendisk); +/* + * The gendisk usage of badblocks does not track acknowledgements for + * badblocks. We always assume they are acknowledged. + */ +int disk_check_badblocks(struct gendisk *disk, sector_t s, int sectors, + sector_t *first_bad, int *bad_sectors) +{ + return badblocks_check(disk->bb, s, sectors, first_bad, bad_sectors); +} +EXPORT_SYMBOL(disk_check_badblocks); + +int disk_set_badblocks(struct gendisk *disk, sector_t s, int sectors) +{ + return badblocks_set(disk->bb, s, sectors, 1); +} +EXPORT_SYMBOL(disk_set_badblocks); + +int disk_clear_badblocks(struct gendisk *disk, sector_t s, int sectors) +{ + return badblocks_clear(disk->bb, s, sectors); +} +EXPORT_SYMBOL(disk_clear_badblocks); + +/* sysfs access to bad-blocks list. */ +static ssize_t disk_badblocks_show(struct device *dev, + struct device_attribute *attr, + char *page) +{ + struct gendisk *disk = dev_to_disk(dev); + + return badblocks_show(disk->bb, page, 0); +} + +static ssize_t disk_badblocks_store(struct device *dev, + struct device_attribute *attr, + const char *page, size_t len) +{ + struct gendisk *disk = dev_to_disk(dev); + + return badblocks_store(disk->bb, page, len, 0); +} + /** * get_gendisk - get partitioning information for a given device * @devt: device to get partitioning information for @@ -988,6 +1049,8 @@ static DEVICE_ATTR(discard_alignment, S_IRUGO, disk_discard_alignment_show, static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL); static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL); static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL); +static DEVICE_ATTR(badblocks, S_IRUGO | S_IWUSR, disk_badblocks_show, + disk_badblocks_store); #ifdef CONFIG_FAIL_MAKE_REQUEST static struct device_attribute dev_attr_fail = __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store); @@ -1009,6 +1072,7 @@ static struct attribute *disk_attrs[] = { &dev_attr_capability.attr, &dev_attr_stat.attr, &dev_attr_inflight.attr, + &dev_attr_badblocks.attr, #ifdef CONFIG_FAIL_MAKE_REQUEST &dev_attr_fail.attr, #endif diff --git a/include/linux/genhd.h b/include/linux/genhd.h index 2adbfa6..5563bde 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -162,6 +162,7 @@ struct disk_part_tbl { }; struct disk_events; +struct badblocks; struct gendisk { /* major, first_minor and minors are input parameters only, @@ -201,6 +202,7 @@ struct gendisk { struct blk_integrity *integrity; #endif int node_id; + struct badblocks *bb; }; static inline struct gendisk *part_to_disk(struct hd_struct *part) @@ -421,6 +423,10 @@ extern void add_disk(struct gendisk *disk); extern void del_gendisk(struct gendisk *gp); extern struct gendisk *get_gendisk(dev_t dev, int *partno); extern struct block_device *bdget_disk(struct gendisk *disk, int partno); +extern int disk_check_badblocks(struct gendisk *disk, sector_t s, int sectors, + sector_t *first_bad, int *bad_sectors); +extern int disk_set_badblocks(struct gendisk *disk, sector_t s, int sectors); +extern int disk_clear_badblocks(struct gendisk *disk, sector_t s, int sectors); extern void set_device_ro(struct block_device *bdev, int flag); extern void set_disk_ro(struct gendisk *disk, int flag);