pmem: add proper fencing to pmem_rw_page()

commit ba8fe0f85e15d047686caf8a42463b592c63c98c upstream.

pmem_rw_page() needs to call wmb_pmem() on writes to make sure that the
newly written data is durable.  This flow was added to pmem_rw_bytes()
and pmem_make_request() with this commit:

commit 61031952f4c8 ("arch, x86: pmem api for ensuring durability of
	persistent memory updates")

...the pmem_rw_page() path was missed.

Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index ade9eb917a4d945b4ff9bd69ebbed1b3fedfd742..b796d1bd8988cbcf0b034a6c4fdfd37cd7edfc79 100644 (file)
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -86,6 +86,8 @@ static int pmem_rw_page(struct block_device *bdev, sector_t sector,
        struct pmem_device *pmem = bdev->bd_disk->private_data;
 
        pmem_do_bvec(pmem, page, PAGE_CACHE_SIZE, 0, rw, sector);
+       if (rw & WRITE)
+               wmb_pmem();
        page_endio(page, rw & WRITE, 0);
 
        return 0;