From patchwork Wed Jun 23 10:58:53 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matteo Croce X-Patchwork-Id: 12339563 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 5400BC48BE5 for ; Wed, 23 Jun 2021 10:59:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3430C61166 for ; Wed, 23 Jun 2021 10:59:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230135AbhFWLCG (ORCPT ); Wed, 23 Jun 2021 07:02:06 -0400 Received: from mail-wr1-f50.google.com ([209.85.221.50]:33379 "EHLO mail-wr1-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230030AbhFWLCF (ORCPT ); Wed, 23 Jun 2021 07:02:05 -0400 Received: by mail-wr1-f50.google.com with SMTP id d11so2200147wrm.0; Wed, 23 Jun 2021 03:59:48 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=3DPuzTQf5i//60Egy7t0JK45QLGYkeuhTcZ4qyrJF2Q=; b=QHh6nSjmKLtSs3xhgnYvjIHKfRKDeNjmDys3VQCHHHUc1SdDUF6O1dhaJH2knCAUKF +kas3sSPMd3swkfrQJjiA+N6dlPcQtFBux2bXDL23xOg1Q4+37MHT7ENJJ8KLD+lTjx4 8ZfEdG0blK61M5yZMc6+1XNqmB1jjUeBYlztBiezHN8OXZdH0or5pnVtC8YplCauvowF MoTLZdVJqzBH8u2L90XH4sKPjxBUnnsh5wlTQ4OG13dU2HAqCPR30WyYWGTbCRKqeruN 61BtCe+h9tjy4GgzwwFmmm7pXualj50HSd6EzD2FXzgXshuYExOo3jblT/texcNVmQLD ioqw== X-Gm-Message-State: AOAM533Fy4FBTAUD79PHRaCPGxlZtrziH0AvefSt26iccUcE/gSLNPkd cLoBcbW3Rj1eiCKnQtgqTR6XUoZ6ZLEI1Q== X-Google-Smtp-Source: ABdhPJwPvauXSCj+gS+SHMy12LE2IiuMDMEOc9jf+z6vkeE9bJ0CDWIYXAOMvF1JZ0m4GGYQE0W3yg== X-Received: by 2002:a05:6000:1245:: with SMTP id j5mr10683561wrx.371.1624445987343; Wed, 23 Jun 2021 03:59:47 -0700 (PDT) Received: from msft-t490s.. (mob-176-246-29-26.net.vodafone.it. [176.246.29.26]) by smtp.gmail.com with ESMTPSA id r2sm2659458wrv.39.2021.06.23.03.59.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 23 Jun 2021 03:59:46 -0700 (PDT) From: Matteo Croce To: linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, Jens Axboe Cc: linux-kernel@vger.kernel.org, Lennart Poettering , Luca Boccassi , Alexander Viro , Damien Le Moal , Tejun Heo , =?utf-8?q?Javier_Gonz=C3=A1lez?= , Niklas Cassel , Johannes Thumshirn , Hannes Reinecke , Matthew Wilcox , Christoph Hellwig , JeffleXu Subject: [PATCH v3 1/6] block: add disk sequence number Date: Wed, 23 Jun 2021 12:58:53 +0200 Message-Id: <20210623105858.6978-2-mcroce@linux.microsoft.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210623105858.6978-1-mcroce@linux.microsoft.com> References: <20210623105858.6978-1-mcroce@linux.microsoft.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: Matteo Croce Add a monotonically increasing number to disk devices. This number is put in the uevent so userspace can correlate events when a driver reuses a device, like cdrom or loop. $ udevadm info /sys/class/block/* |grep -e DEVNAME -e DISKSEQ E: DEVNAME=/dev/loop0 E: DISKSEQ=1 E: DEVNAME=/dev/loop1 E: DISKSEQ=2 E: DEVNAME=/dev/loop2 E: DISKSEQ=3 E: DEVNAME=/dev/loop3 E: DISKSEQ=4 E: DEVNAME=/dev/loop4 E: DISKSEQ=5 E: DEVNAME=/dev/loop5 E: DISKSEQ=6 E: DEVNAME=/dev/loop6 E: DISKSEQ=7 E: DEVNAME=/dev/loop7 E: DISKSEQ=8 E: DEVNAME=/dev/nvme0n1 E: DISKSEQ=9 E: DEVNAME=/dev/nvme0n1p1 E: DISKSEQ=9 E: DEVNAME=/dev/nvme0n1p2 E: DISKSEQ=9 E: DEVNAME=/dev/nvme0n1p3 E: DISKSEQ=9 E: DEVNAME=/dev/nvme0n1p4 E: DISKSEQ=9 E: DEVNAME=/dev/nvme0n1p5 E: DISKSEQ=9 E: DEVNAME=/dev/sda E: DISKSEQ=10 E: DEVNAME=/dev/sda1 E: DISKSEQ=10 E: DEVNAME=/dev/sda2 E: DISKSEQ=10 Signed-off-by: Matteo Croce --- block/genhd.c | 19 +++++++++++++++++++ include/linux/genhd.h | 2 ++ 2 files changed, 21 insertions(+) diff --git a/block/genhd.c b/block/genhd.c index 9f8cb7beaad1..c96b667136ee 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -1129,8 +1129,17 @@ static void disk_release(struct device *dev) blk_put_queue(disk->queue); kfree(disk); } + +static int block_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + struct gendisk *disk = dev_to_disk(dev); + + return add_uevent_var(env, "DISKSEQ=%llu", disk->diskseq); +} + struct class block_class = { .name = "block", + .dev_uevent = block_uevent, }; static char *block_devnode(struct device *dev, umode_t *mode, @@ -1304,6 +1313,8 @@ struct gendisk *__alloc_disk_node(int minors, int node_id) disk_to_dev(disk)->class = &block_class; disk_to_dev(disk)->type = &disk_type; device_initialize(disk_to_dev(disk)); + inc_diskseq(disk); + return disk; out_destroy_part_tbl: @@ -1854,3 +1865,11 @@ static void disk_release_events(struct gendisk *disk) WARN_ON_ONCE(disk->ev && disk->ev->block != 1); kfree(disk->ev); } + +void inc_diskseq(struct gendisk *disk) +{ + static atomic64_t diskseq; + + disk->diskseq = atomic64_inc_return(&diskseq); +} +EXPORT_SYMBOL_GPL(inc_diskseq); diff --git a/include/linux/genhd.h b/include/linux/genhd.h index 6fc26f7bdf71..a0d04250a2db 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -167,6 +167,7 @@ struct gendisk { int node_id; struct badblocks *bb; struct lockdep_map lockdep_map; + u64 diskseq; }; /* @@ -306,6 +307,7 @@ static inline void bd_unlink_disk_holder(struct block_device *bdev, } #endif /* CONFIG_SYSFS */ +void inc_diskseq(struct gendisk *disk); dev_t blk_lookup_devt(const char *name, int partno); void blk_request_module(dev_t devt); #ifdef CONFIG_BLOCK