From mboxrd@z Thu Jan 1 00:00:00 1970 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=-13.7 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 23A79C63777 for ; Sat, 28 Nov 2020 16:22:18 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9BA39246C3 for ; Sat, 28 Nov 2020 16:22:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9BA39246C3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=tempfail smtp.mailfrom=dm-devel-bounces@redhat.com Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-311-h_wsByo7OCWrDwJJnchALg-1; Sat, 28 Nov 2020 11:22:14 -0500 X-MC-Unique: h_wsByo7OCWrDwJJnchALg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 12886107AD42; Sat, 28 Nov 2020 16:22:10 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E5D011A88B; Sat, 28 Nov 2020 16:22:09 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id C00411809CA0; Sat, 28 Nov 2020 16:22:09 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id 0ASGM72t023249 for ; Sat, 28 Nov 2020 11:22:07 -0500 Received: by smtp.corp.redhat.com (Postfix) id 7FF3347CE1; Sat, 28 Nov 2020 16:22:07 +0000 (UTC) Received: from mimecast-mx02.redhat.com (mimecast05.extmail.prod.ext.rdu2.redhat.com [10.11.55.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7ACF547CDC for ; Sat, 28 Nov 2020 16:22:07 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-2.mimecast.com [207.211.31.81]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6869E800969 for ; Sat, 28 Nov 2020 16:22:07 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-25-NDD8z5QaMii7GMGYUDPxsA-1; Sat, 28 Nov 2020 11:22:02 -0500 X-MC-Unique: NDD8z5QaMii7GMGYUDPxsA-1 Received: from [2001:4bb8:18c:1dd6:48f3:741a:602e:7fdd] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kj2sr-0000G4-Tr; Sat, 28 Nov 2020 16:15:38 +0000 From: Christoph Hellwig To: Jens Axboe Date: Sat, 28 Nov 2020 17:14:41 +0100 Message-Id: <20201128161510.347752-17-hch@lst.de> In-Reply-To: <20201128161510.347752-1-hch@lst.de> References: <20201128161510.347752-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html X-Mimecast-Impersonation-Protect: Policy=CLT - Impersonation Protection Definition; Similar Internal Domain=false; Similar Monitored External Domain=false; Custom External Domain=false; Mimecast External Domain=false; Newly Observed Domain=false; Internal User Name=false; Custom Display Name List=false; Reply-to Address Mismatch=false; Targeted Threat Dictionary=false; Mimecast Threat Dictionary=false; Custom Threat Dictionary=false X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-loop: dm-devel@redhat.com Cc: linux-bcache@vger.kernel.org, Jan Kara , Mike Snitzer , linux-mm@kvack.org, Greg Kroah-Hartman , Jan Kara , Josef Bacik , Coly Li , linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, dm-devel@redhat.com, linux-mtd@lists.infradead.org, Johannes Thumshirn , Tejun Heo Subject: [dm-devel] [PATCH 16/45] block: switch bdgrab to use igrab X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dm-devel-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit All of the current callers already have a reference, but to prepare for additional users ensure bdgrab returns NULL if the block device is beeing freed. Signed-off-by: Christoph Hellwig --- fs/block_dev.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/fs/block_dev.c b/fs/block_dev.c index d707ab376da86e..962fabe8a67b83 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -894,10 +894,14 @@ static struct block_device *bdget(dev_t dev) /** * bdgrab -- Grab a reference to an already referenced block device * @bdev: Block device to grab a reference to. + * + * Returns the block_device with an additional reference when successful, + * or NULL if the inode is already beeing freed. */ struct block_device *bdgrab(struct block_device *bdev) { - ihold(bdev->bd_inode); + if (!igrab(bdev->bd_inode)) + return NULL; return bdev; } EXPORT_SYMBOL(bdgrab); -- 2.29.2 -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel