From 0b277961f4484fb3f142caaa1dd1748cb0b2cbee Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Fri, 9 Jun 2017 09:46:50 -0700 Subject: libnvdimm, pmem: disable dax flushing when pmem is fronting a volatile region The pmem driver attaches to both persistent and volatile memory ranges advertised by the ACPI NFIT. When the region is volatile it is redundant to spend cycles flushing caches at fsync(). Check if the hosting region is volatile and do not set dax_write_cache() if it is. Cc: Jan Kara Cc: Jeff Moyer Cc: Christoph Hellwig Cc: Matthew Wilcox Cc: Ross Zwisler Signed-off-by: Dan Williams --- include/linux/libnvdimm.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h index b2f659bd661d..a8ee1d0afd70 100644 --- a/include/linux/libnvdimm.h +++ b/include/linux/libnvdimm.h @@ -165,4 +165,5 @@ void nd_region_release_lane(struct nd_region *nd_region, unsigned int lane); u64 nd_fletcher64(void *addr, size_t len, bool le); void nvdimm_flush(struct nd_region *nd_region); int nvdimm_has_flush(struct nd_region *nd_region); +int nvdimm_has_cache(struct nd_region *nd_region); #endif /* __LIBNVDIMM_H__ */ -- cgit v1.2.3