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Mon, 30 Nov 2020 09:52:00 -0500 Received: by smtp.corp.redhat.com (Postfix) id 4DF361111A51; Mon, 30 Nov 2020 14:52:00 +0000 (UTC) Received: from mimecast-mx02.redhat.com (mimecast01.extmail.prod.ext.rdu2.redhat.com [10.11.55.17]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 48E4D1111A50 for ; Mon, 30 Nov 2020 14:51:57 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [205.139.110.120]) (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 CE114858287 for ; Mon, 30 Nov 2020 14:51:57 +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-344-1IDdYRajMBa0WF4_vZ0Qww-1; Mon, 30 Nov 2020 09:51:53 -0500 X-MC-Unique: 1IDdYRajMBa0WF4_vZ0Qww-1 Received: by verein.lst.de (Postfix, from userid 2407) id 3C4A86736F; Mon, 30 Nov 2020 15:51:50 +0100 (CET) Date: Mon, 30 Nov 2020 15:51:50 +0100 From: Christoph Hellwig To: Jan Kara Message-ID: <20201130145150.GA24694@lst.de> References: <20201128161510.347752-1-hch@lst.de> <20201128161510.347752-31-hch@lst.de> <20201130094421.GD11250@quack2.suse.cz> MIME-Version: 1.0 In-Reply-To: <20201130094421.GD11250@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 10.11.54.3 X-loop: dm-devel@redhat.com Cc: Jens Axboe , Chao Yu , 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 , linux-bcache@vger.kernel.org, Christoph Hellwig Subject: Re: [dm-devel] [PATCH 30/45] block: remove the nr_sects field in struct hd_struct 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 10.5.11.12 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 Mon, Nov 30, 2020 at 10:44:21AM +0100, Jan Kara wrote: > I know I'm like a broken record about this but I still don't understand > here... I'd expect the new code to be: > > if (size == capacity || > (disk->flags & (GENHD_FL_UP | GENHD_FL_HIDDEN)) != GENHD_FL_UP) > return false; > pr_info("%s: detected capacity change from %lld to %lld\n", > disk->disk_name, size, capacity); > + if (!capacity || !size) > + return false; > kobject_uevent_env(&disk_to_dev(disk)->kobj, KOBJ_CHANGE, envp); > return true; > > At least that would be equivalent to the original functionality of > set_capacity_and_notify(). And if you indeed intend to change when > "RESIZE=1" events are sent, then I'd expect an explanation in the changelog > why this cannot break userspace (I remember we've already broken some udev > rules in the past by generating unexpected events and we had to revert > those changes in the partition code so I'm more careful now). The rest of > the patch looks good to me. I explained that I think the GENHD_FL_UP is the more useful one here in reply to your last comment. If the size changes to or from 0 during runtime we probably do want an event. But I'll add your hunk for now and we can discuss this separately. -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel