From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sender-pp-092.zoho.com ([135.84.80.237]:25309 "EHLO sender-pp-092.zoho.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728663AbeGYRm1 (ORCPT ); Wed, 25 Jul 2018 13:42:27 -0400 From: Huaisheng Ye To: linux-nvdimm@lists.01.org, dan.j.williams@intel.com Cc: ross.zwisler@linux.intel.com, willy@infradead.org, vishal.l.verma@intel.com, dave.jiang@intel.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, viro@zeniv.linux.org.uk, martin.petersen@oracle.com, axboe@kernel.dk, gregkh@linuxfoundation.org, bart.vanassche@wdc.com, jack@suse.cz, agk@redhat.com, snitzer@redhat.com, dm-devel@redhat.com, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, linux-fsdevel@vger.kernel.org, chengnt@lenovo.com, colyli@suse.de, Huaisheng Ye Subject: [PATCH v2 3/6] tools/testing/nvdimm: kaddr and pfn can be NULL to ->direct_access() Date: Thu, 26 Jul 2018 00:28:46 +0800 Message-Id: <20180725162849.8320-4-yehs2007@zoho.com> In-Reply-To: <20180725162849.8320-1-yehs2007@zoho.com> References: <20180725162849.8320-1-yehs2007@zoho.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: From: Huaisheng Ye The mock / test version of 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 local pointer or variable that they then just throw away. Suggested-by: Dan Williams Signed-off-by: Huaisheng Ye --- tools/testing/nvdimm/pmem-dax.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/tools/testing/nvdimm/pmem-dax.c b/tools/testing/nvdimm/pmem-dax.c index b53596a..2e7fd82 100644 --- a/tools/testing/nvdimm/pmem-dax.c +++ b/tools/testing/nvdimm/pmem-dax.c @@ -31,17 +31,21 @@ long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff, if (get_nfit_res(pmem->phys_addr + offset)) { struct page *page; - *kaddr = pmem->virt_addr + offset; + if (kaddr) + *kaddr = pmem->virt_addr + offset; page = vmalloc_to_page(pmem->virt_addr + offset); - *pfn = page_to_pfn_t(page); + if (pfn) + *pfn = page_to_pfn_t(page); pr_debug_ratelimited("%s: pmem: %p pgoff: %#lx pfn: %#lx\n", __func__, pmem, pgoff, page_to_pfn(page)); return 1; } - *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 -- 1.8.3.1