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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 96A88C56202 for ; Wed, 25 Nov 2020 16:23:16 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [63.128.21.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6BF8D206F7 for ; Wed, 25 Nov 2020 16:23:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6BF8D206F7 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-584-ma8Pk4qeNXmmR2W6XgmAKg-1; Wed, 25 Nov 2020 11:23:12 -0500 X-MC-Unique: ma8Pk4qeNXmmR2W6XgmAKg-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 92BF2185E482; Wed, 25 Nov 2020 16:23:07 +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 09AB960854; Wed, 25 Nov 2020 16:23:06 +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 19C31180954D; Wed, 25 Nov 2020 16:23:04 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id 0APGN2VI004910 for ; Wed, 25 Nov 2020 11:23:02 -0500 Received: by smtp.corp.redhat.com (Postfix) id 06F242166B2B; Wed, 25 Nov 2020 16:23:02 +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 018132166B29 for ; Wed, 25 Nov 2020 16:22:59 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-1.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 D979B802A5D for ; Wed, 25 Nov 2020 16:22:59 +0000 (UTC) Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-591-vkmhNliJMzuVHu1K2LDw9g-1; Wed, 25 Nov 2020 11:22:55 -0500 X-MC-Unique: vkmhNliJMzuVHu1K2LDw9g-1 Received: by verein.lst.de (Postfix, from userid 2407) id 4507168B02; Wed, 25 Nov 2020 17:22:50 +0100 (CET) Date: Wed, 25 Nov 2020 17:22:50 +0100 From: Christoph Hellwig To: Jan Kara Message-ID: <20201125162250.GA795@lst.de> References: <20201124132751.3747337-1-hch@lst.de> <20201124132751.3747337-5-hch@lst.de> <20201125122953.GH16944@quack2.suse.cz> MIME-Version: 1.0 In-Reply-To: <20201125122953.GH16944@quack2.suse.cz> User-Agent: Mutt/1.5.17 (2007-11-01) 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 2.78 on 10.11.54.6 X-loop: dm-devel@redhat.com Cc: Jens Axboe , linux-fsdevel@vger.kernel.org, Mike Snitzer , Konrad Rzeszutek Wilk , Greg Kroah-Hartman , Jan Kara , Josef Bacik , Coly Li , linux-block@vger.kernel.org, Richard Weinberger , dm-devel@redhat.com, linux-mtd@lists.infradead.org, linux-mm@kvack.org, Johannes Thumshirn , Tejun Heo , xen-devel@lists.xenproject.org, linux-bcache@vger.kernel.org, Christoph Hellwig Subject: Re: [dm-devel] [PATCH 04/45] fs: simplify freeze_bdev/thaw_bdev 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 2.79 on 10.5.11.13 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-Disposition: inline Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Wed, Nov 25, 2020 at 01:29:53PM +0100, Jan Kara wrote: > > mutex_unlock(&bdev->bd_fsfreeze_mutex); > > - return sb; /* thaw_bdev releases s->s_umount */ > > + return error; /* thaw_bdev releases s->s_umount */ > > The comment about thaw_bdev() seems to be stale? At least I don't see what > it's speaking about... Yes, this comment seems long stale. I think in the very early days we held s_umount on frozen file system, which caused all kinds of problems. > > mutex_unlock(&bdev->bd_fsfreeze_mutex); > > - return error; > > + return 0; > > But we now won't return -EINVAL if this gets called e.g. with > bd_fsfreeze_count == 0, right? Yes. I had tried to drop the return value as all the freeze_bdev calls ignored it. But I had missed the unpaired emergency thaw and put it back and messed this up.. -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel 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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 EEFFCC56201 for ; Wed, 25 Nov 2020 16:22:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ACD3E20789 for ; Wed, 25 Nov 2020 16:22:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730560AbgKYQW4 (ORCPT ); Wed, 25 Nov 2020 11:22:56 -0500 Received: from verein.lst.de ([213.95.11.211]:59598 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729755AbgKYQW4 (ORCPT ); Wed, 25 Nov 2020 11:22:56 -0500 Received: by verein.lst.de (Postfix, from userid 2407) id 4507168B02; Wed, 25 Nov 2020 17:22:50 +0100 (CET) Date: Wed, 25 Nov 2020 17:22:50 +0100 From: Christoph Hellwig To: Jan Kara Cc: Christoph Hellwig , Jens Axboe , Tejun Heo , Josef Bacik , Konrad Rzeszutek Wilk , Coly Li , Mike Snitzer , Greg Kroah-Hartman , Johannes Thumshirn , dm-devel@redhat.com, Richard Weinberger , Jan Kara , linux-block@vger.kernel.org, xen-devel@lists.xenproject.org, linux-bcache@vger.kernel.org, linux-mtd@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 04/45] fs: simplify freeze_bdev/thaw_bdev Message-ID: <20201125162250.GA795@lst.de> References: <20201124132751.3747337-1-hch@lst.de> <20201124132751.3747337-5-hch@lst.de> <20201125122953.GH16944@quack2.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201125122953.GH16944@quack2.suse.cz> User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-bcache@vger.kernel.org On Wed, Nov 25, 2020 at 01:29:53PM +0100, Jan Kara wrote: > > mutex_unlock(&bdev->bd_fsfreeze_mutex); > > - return sb; /* thaw_bdev releases s->s_umount */ > > + return error; /* thaw_bdev releases s->s_umount */ > > The comment about thaw_bdev() seems to be stale? At least I don't see what > it's speaking about... Yes, this comment seems long stale. I think in the very early days we held s_umount on frozen file system, which caused all kinds of problems. > > mutex_unlock(&bdev->bd_fsfreeze_mutex); > > - return error; > > + return 0; > > But we now won't return -EINVAL if this gets called e.g. with > bd_fsfreeze_count == 0, right? Yes. I had tried to drop the return value as all the freeze_bdev calls ignored it. But I had missed the unpaired emergency thaw and put it back and messed this up.. 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=-5.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 659C6C6379D for ; Wed, 25 Nov 2020 16:24:16 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id EF641206F7 for ; Wed, 25 Nov 2020 16:24:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="oNxpXNvR" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EF641206F7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=0pinuvjZlVU3AbVtZUwEg7l0gF3LBIcD3wSSOx7JRyo=; b=oNxpXNvRrdIuZGcCxlgKkzqj3 HfoPfDx3MoNZxunLPvie5dTIpxZM4kb51LyJPuo4pFAeYqjQcSgve8Fx3MhPOKbAutbBP0z141Vzo qVCGUAbaU0P6gq9zRC+uouG78uvBcV8UUFCaWmNrKi1Q1/f1IrZdgGGLoW6SZN8xdTv0iUT82rXug JqEb5ZaEqmWQtvhrUuKXkA2D5BMuM3u3+28HkOKCQBMLkg1Pqdq0/OG1LeuuGMQ6Yi17yY3R+7+Nf 5C8RoQSRPi/8epOYDFSj25CSpA4cZ532jJV5UEcB2vzs2AeHqn/JVrsyuVZTNvLnJdPrw/r0VTmmy 6+IY+Ji1g==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1khxZJ-0000gX-D2; Wed, 25 Nov 2020 16:22:57 +0000 Received: from verein.lst.de ([213.95.11.211]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1khxZG-0000fc-CL for linux-mtd@lists.infradead.org; Wed, 25 Nov 2020 16:22:55 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 4507168B02; Wed, 25 Nov 2020 17:22:50 +0100 (CET) Date: Wed, 25 Nov 2020 17:22:50 +0100 From: Christoph Hellwig To: Jan Kara Subject: Re: [PATCH 04/45] fs: simplify freeze_bdev/thaw_bdev Message-ID: <20201125162250.GA795@lst.de> References: <20201124132751.3747337-1-hch@lst.de> <20201124132751.3747337-5-hch@lst.de> <20201125122953.GH16944@quack2.suse.cz> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20201125122953.GH16944@quack2.suse.cz> User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201125_112254_582221_52CD3C22 X-CRM114-Status: GOOD ( 13.28 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jens Axboe , linux-fsdevel@vger.kernel.org, Mike Snitzer , Konrad Rzeszutek Wilk , Greg Kroah-Hartman , Jan Kara , Josef Bacik , Coly Li , linux-block@vger.kernel.org, Richard Weinberger , dm-devel@redhat.com, linux-mtd@lists.infradead.org, linux-mm@kvack.org, Johannes Thumshirn , Tejun Heo , xen-devel@lists.xenproject.org, linux-bcache@vger.kernel.org, Christoph Hellwig Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org On Wed, Nov 25, 2020 at 01:29:53PM +0100, Jan Kara wrote: > > mutex_unlock(&bdev->bd_fsfreeze_mutex); > > - return sb; /* thaw_bdev releases s->s_umount */ > > + return error; /* thaw_bdev releases s->s_umount */ > > The comment about thaw_bdev() seems to be stale? At least I don't see what > it's speaking about... Yes, this comment seems long stale. I think in the very early days we held s_umount on frozen file system, which caused all kinds of problems. > > mutex_unlock(&bdev->bd_fsfreeze_mutex); > > - return error; > > + return 0; > > But we now won't return -EINVAL if this gets called e.g. with > bd_fsfreeze_count == 0, right? Yes. I had tried to drop the return value as all the freeze_bdev calls ignored it. But I had missed the unpaired emergency thaw and put it back and messed this up.. ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/