From: Huaisheng Ye <yehs1@xxxxxxxxxx> 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 <yehs1@xxxxxxxxxx> Reviewed-by: Jan Kara <jack@xxxxxxx> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> --- 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
