From 5fdf8e5ba5666fe153bd61f851a40078a6347822 Mon Sep 17 00:00:00 2001 From: Dave Jiang Date: Fri, 2 Mar 2018 19:31:40 -0800 Subject: [PATCH] libnvdimm: re-enable deep flush for pmem devices via fsync() Re-enable deep flush so that users always have a way to be sure that a write makes it all the way out to media. Writes from the PMEM driver always arrive at the NVDIMM since movnt is used to bypass the cache, and the driver relies on the ADR (Asynchronous DRAM Refresh) mechanism to flush write buffers on power failure. The Deep Flush mechanism is there to explicitly write buffers to protect against (rare) ADR failure. This change prevents a regression in deep flush behavior so that applications can continue to depend on fsync() as a mechanism to trigger deep flush in the filesystem-DAX case. Fixes: 06e8ccdab15f4 ("acpi: nfit: Add support for detect platform CPU cache...") Reviewed-by: Jeff Moyer Signed-off-by: Dave Jiang Signed-off-by: Dan Williams --- drivers/nvdimm/pmem.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 10041ac4032c..06f8dcc52ca6 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -335,8 +335,7 @@ static int pmem_attach_disk(struct device *dev, dev_warn(dev, "unable to guarantee persistence of writes\n"); fua = 0; } - wbc = nvdimm_has_cache(nd_region) && - !test_bit(ND_REGION_PERSIST_CACHE, &nd_region->flags); + wbc = nvdimm_has_cache(nd_region); if (!devm_request_mem_region(dev, res->start, resource_size(res), dev_name(&ndns->dev))) {