[PATCH 2/5] tools/testing/nvdimm: Allow a NULL-kaddr to ->direct_access()

[Huaisheng Ye]

From: Huaisheng Ye <yehs1@xxxxxxxxxx>

The mock / test version of pmem_direct_access() needs to check the
validity of second rank pointer kaddr for NULL assignment. If kaddr
equals to NULL, it doesn't need to calculate the value.

Signed-off-by: Huaisheng Ye <yehs1@xxxxxxxxxx>
---
 tools/testing/nvdimm/pmem-dax.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tools/testing/nvdimm/pmem-dax.c b/tools/testing/nvdimm/pmem-dax.c
index b53596a..c3ba159 100644
--- a/tools/testing/nvdimm/pmem-dax.c
+++ b/tools/testing/nvdimm/pmem-dax.c
@@ -31,7 +31,8 @@ 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);
 		pr_debug_ratelimited("%s: pmem: %p pgoff: %#lx pfn: %#lx\n",
@@ -40,7 +41,8 @@ long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
 		return 1;
 	}
 
-	*kaddr = pmem->virt_addr + offset;
+	if (kaddr)
+		*kaddr = pmem->virt_addr + offset;
 	*pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
 
 	/*
-- 
1.8.3.1