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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 0C1B9C433E7 for ; Fri, 16 Oct 2020 10:20:20 +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 00F2420848 for ; Fri, 16 Oct 2020 10:20:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 00F2420848 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org 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-199-ld4UYfSrP52sZY6Hseyd0g-1; Fri, 16 Oct 2020 06:20:15 -0400 X-MC-Unique: ld4UYfSrP52sZY6Hseyd0g-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1248964095; Fri, 16 Oct 2020 10:20:10 +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 EA45276649; Fri, 16 Oct 2020 10:20:09 +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 BF578180B791; Fri, 16 Oct 2020 10:20:09 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id 09G7UHrK029227 for ; Fri, 16 Oct 2020 03:30:18 -0400 Received: by smtp.corp.redhat.com (Postfix) id 88F461067CD9; Fri, 16 Oct 2020 07:30:17 +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 847D31067DA4 for ; Fri, 16 Oct 2020 07:30:15 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-2.mimecast.com [205.139.110.61]) (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 3FC48805F53 for ; Fri, 16 Oct 2020 07:30:15 +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-570-EUdLd7pAP0ung2SZwdMWEw-1; Fri, 16 Oct 2020 03:30:13 -0400 X-MC-Unique: EUdLd7pAP0ung2SZwdMWEw-1 Received: from hch by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1kTK1d-00049y-2X; Fri, 16 Oct 2020 07:19:41 +0000 Date: Fri, 16 Oct 2020 08:19:41 +0100 From: Christoph Hellwig To: Satya Tangirala Message-ID: <20201016071941.GA14885@infradead.org> References: <20201015214632.41951-1-satyat@google.com> <20201015214632.41951-3-satyat@google.com> MIME-Version: 1.0 In-Reply-To: <20201015214632.41951-3-satyat@google.com> 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 2.78 on 10.11.54.3 X-loop: dm-devel@redhat.com X-Mailman-Approved-At: Fri, 16 Oct 2020 06:18:44 -0400 Cc: Jens Axboe , Mike Snitzer , Eric Biggers , linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, dm-devel@redhat.com, Alasdair Kergon Subject: Re: [dm-devel] [PATCH v2 2/4] block: add private field to struct keyslot_manager 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 10.5.11.11 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 Thu, Oct 15, 2020 at 09:46:30PM +0000, Satya Tangirala wrote: > Add a (void *) pointer to struct keyslot_manager that the owner of the > struct can use for any purpose it wants. > > Right now, the struct keyslot_manager is expected to be embedded directly > into other structs (and the owner of the keyslot_manager would use > container_of() to access any other data the owner needs). However, this > might take up more space than is acceptable, and it would be better to be > able to add only a pointer to a struct keyslot_manager into other structs > rather than embed the entire struct directly. But container_of() can't be > used when only the pointer to the keyslot_manager is embded. The primary > motivation of this patch is to get around that issue. No, please don't bloat the structure. If some weird caller doesn't like the embedding it can create a container structure with the blk_keyslot_manager structure and a backpointer. -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel