From patchwork Mon Jul 16 17:00:58 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Williams X-Patchwork-Id: 10527259 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 918FD60545 for ; Mon, 16 Jul 2018 17:11:10 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 77B3428D80 for ; Mon, 16 Jul 2018 17:11:10 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6BA8328D82; Mon, 16 Jul 2018 17:11:10 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 154B728D82 for ; Mon, 16 Jul 2018 17:11:10 +0000 (UTC) Received: from [127.0.0.1] (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 10DAB209884C0; Mon, 16 Jul 2018 10:11:10 -0700 (PDT) X-Original-To: linux-nvdimm@lists.01.org Delivered-To: linux-nvdimm@lists.01.org Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=192.55.52.43; helo=mga05.intel.com; envelope-from=dan.j.williams@intel.com; receiver=linux-nvdimm@lists.01.org Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 34F142097DD18 for ; Mon, 16 Jul 2018 10:11:09 -0700 (PDT) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 16 Jul 2018 10:11:08 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,362,1526367600"; d="scan'208";a="216447242" Received: from dwillia2-desk3.jf.intel.com (HELO dwillia2-desk3.amr.corp.intel.com) ([10.54.39.16]) by orsmga004.jf.intel.com with ESMTP; 16 Jul 2018 10:10:55 -0700 Subject: [PATCH v2 07/14] libnvdimm, pmem: Allow a NULL-pfn to ->direct_access() From: Dan Williams To: akpm@linux-foundation.org Date: Mon, 16 Jul 2018 10:00:58 -0700 Message-ID: <153176045824.12695.14255237229973044333.stgit@dwillia2-desk3.amr.corp.intel.com> In-Reply-To: <153176041838.12695.3365448145295112857.stgit@dwillia2-desk3.amr.corp.intel.com> References: <153176041838.12695.3365448145295112857.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.18-2-gc94f MIME-Version: 1.0 X-BeenThere: linux-nvdimm@lists.01.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: "Linux-nvdimm developer list." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: jack@suse.cz, linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, hch@lst.de Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" X-Virus-Scanned: ClamAV using ClamSMTP From: Huaisheng Ye pmem_direct_access() needs to check the validity of pointer pfn for NULL assignment. If pfn equals to NULL, it doesn't need to calculate the value. This is in support of asynchronous memmap init and avoid page lookups when possible. Signed-off-by: Huaisheng Ye Reviewed-by: Jan Kara Signed-off-by: Dan Williams --- drivers/nvdimm/pmem.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index e8ac6f244d2b..c430536320a5 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -228,7 +228,8 @@ __weak long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff, PFN_PHYS(nr_pages)))) return -EIO; *kaddr = pmem->virt_addr + offset; - *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags); + if (pfn) + *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags); /* * If badblocks are present, limit known good range to the