From patchwork Mon Jul 30 07:15:43 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Huaisheng Ye X-Patchwork-Id: 10548555 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 81073139A for ; Mon, 30 Jul 2018 07:16:42 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6AB7529741 for ; Mon, 30 Jul 2018 07:16:42 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5EC4F29755; Mon, 30 Jul 2018 07:16:42 +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=-2.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, FREEMAIL_FROM,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 1362129741 for ; Mon, 30 Jul 2018 07:16:42 +0000 (UTC) Received: from [127.0.0.1] (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 10F69210C5153; Mon, 30 Jul 2018 00:16:42 -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=135.84.80.237; helo=sender-pp-092.zoho.com; envelope-from=yehs2007@zoho.com; receiver=linux-nvdimm@lists.01.org Received: from sender-pp-092.zoho.com (sender-pp-092.zoho.com [135.84.80.237]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 9702A210C4DC9 for ; Mon, 30 Jul 2018 00:16:40 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=zapps768; d=zoho.com; h=from:to:cc:subject:date:message-id:in-reply-to:references; b=jTBqWLRQ206iA+xQbDQ+uUjiYq6j3IOCUnQjCtDNQsJ1dwZMA0MLksx/i8fhK6gYIugvXZ66TCCw CJPEa6dhFX3v7XqM8nRpKWBlTMr7ijn2kRdHSLZ7DlMvdIbPR+KQ Received: from YEHS1XR956R00D1.lenovo.com (221.219.122.69 [221.219.122.69]) by mx.zohomail.com with SMTPS id 1532934972894438.38404019626455; Mon, 30 Jul 2018 00:16:12 -0700 (PDT) From: Huaisheng Ye To: linux-nvdimm@lists.01.org, dan.j.williams@intel.com Subject: [PATCH v3 1/6] libnvdimm, pmem: kaddr and pfn can be NULL to ->direct_access() Date: Mon, 30 Jul 2018 15:15:43 +0800 Message-Id: <20180730071548.9172-2-yehs2007@zoho.com> X-Mailer: git-send-email 2.17.0.windows.1 In-Reply-To: <20180730071548.9172-1-yehs2007@zoho.com> References: <20180730071548.9172-1-yehs2007@zoho.com> X-ZohoMailClient: External 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, snitzer@redhat.com, heiko.carstens@de.ibm.com, dm-devel@redhat.com, agk@redhat.com, linux-s390@vger.kernel.org, willy@infradead.org, bart.vanassche@wdc.com, keescook@chromium.org, chengnt@lenovo.com, colyli@suse.de, schwidefsky@de.ibm.com, viro@zeniv.linux.org.uk, axboe@kernel.dk, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org MIME-Version: 1.0 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 pointers kaddr and pfn for NULL assignment. If anyone equals to NULL, it doesn't need to calculate the value. If pointer equals to NULL, that is to say callers may have no need for kaddr or pfn, so this patch is prepared for allowing them to pass in NULL instead of having to pass in a pointer or local variable that they then just throw away. Signed-off-by: Huaisheng Ye Reviewed-by: Ross Zwisler --- drivers/nvdimm/pmem.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 8b1fd7f..ecf9024 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -227,8 +227,11 @@ __weak long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff, if (unlikely(is_bad_pmem(&pmem->bb, PFN_PHYS(pgoff) / 512, PFN_PHYS(nr_pages)))) return -EIO; - *kaddr = pmem->virt_addr + offset; - *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags); + + if (kaddr) + *kaddr = pmem->virt_addr + offset; + if (pfn) + *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags); /* * If badblocks are present, limit known good range to the