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=-4.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 D2771C433E7 for ; Tue, 14 Jul 2020 16:44:17 +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 9FD7420656 for ; Tue, 14 Jul 2020 16:44:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="wx9fb6IF"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="vYhfPqtw" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9FD7420656 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvme-bounces+linux-nvme=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=KqMdu/pYcfRW3dsH1CIbSg4GTD/gA3bYK/yIvw8k640=; b=wx9fb6IFD7F7mcwCNZdnMQIqh 2lEGt9yA70JMd2AnvZC/gw0QfzXWWHU69abDPNS7kGOfQ0RBESDc/siDFUVwTD5Iih4IP9hhhl2WX Sh3xyGD7bH8nLaKq4RCOeAugjtjA6rWAjQkVg/i/sgBgtJWVBaW8NbExl2dbVaY9Zg/EcucQz0vR7 fF/CDcKmMJOTMf2RssHJBEhA0B1ddZjvBvYz1yeM899QSSng74XrhKAQek94I0iLiNCdjV1D1OKUi h6OOLt8Kq6g7dASl3sQTyx8/ZEIz2LkSGhqlhNA0ovNArluYNlbWrQ4A3L9FlyVEVF5pCPEmMwXSZ FJQnHVIew==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jvO2N-0003se-7R; Tue, 14 Jul 2020 16:44:11 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jvO2J-0003rx-Sg for linux-nvme@lists.infradead.org; Tue, 14 Jul 2020 16:44:08 +0000 Received: from dhcp-10-100-145-180.wdl.wdc.com (unknown [199.255.45.60]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E5B6720656; Tue, 14 Jul 2020 16:44:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594745047; bh=6kmndyzEcUa9q5MX7gsltuXTm02RzGywUq2G2kiagP4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=vYhfPqtw0XAwWOB7yRT8+HEPbKigvy4ozMTzWGSPvzFuAyROvNiOJvJ+9VARz1TW1 FzO8oPOcd/gI/u3ctUw7nzHa93hBuXwbxgVSvibguYleW2iRPbBr5NMlcxFf+kTVOH b0KzGl351aK41XQ3r2haI6AKjoPAzkWqNJM1pE0k= Date: Tue, 14 Jul 2020 09:44:05 -0700 From: Keith Busch To: Christoph Hellwig Subject: Re: [PATCH V2 1/2] nvme-core: replace ctrl page size with a macro Message-ID: <20200714164405.GB2771736@dhcp-10-100-145-180.wdl.wdc.com> References: <20200709234025.10673-1-chaitanya.kulkarni@wdc.com> <20200709234025.10673-2-chaitanya.kulkarni@wdc.com> <20200713074210.GB14676@lst.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200713074210.GB14676@lst.de> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200714_124407_998443_BA1F28C4 X-CRM114-Status: GOOD ( 12.46 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-nvme@lists.infradead.org, sagi@grimberg.me, Chaitanya Kulkarni Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Mon, Jul 13, 2020 at 09:42:10AM +0200, Christoph Hellwig wrote: > On Thu, Jul 09, 2020 at 04:40:24PM -0700, Chaitanya Kulkarni wrote: > > static int nvme_npages(unsigned size, struct nvme_dev *dev) > > { > > - unsigned nprps = DIV_ROUND_UP(size + dev->ctrl.page_size, > > - dev->ctrl.page_size); > > + unsigned nprps = DIV_ROUND_UP(size + NVME_CTRL_PAGE_SIZE, > > + NVME_CTRL_PAGE_SIZE); > > return DIV_ROUND_UP(8 * nprps, PAGE_SIZE - 8); > > This looks like the existing code here is wrong, as DIV_ROUND_UP already > adds the page size itself. But that is better left for another patch.. The extra addition is for when the starting address has a page offset, which may require an extra PRP than DIV_ROUND_UP would return without the addition. _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme