[dm-devel] [PATCH v5 1/3] pmem: only set QUEUE_FLAG_DAX for fsdax mode

[Ross Zwisler]

QUEUE_FLAG_DAX is an indication that a given block device supports
filesystem DAX and should not be set for PMEM namespaces which are in "raw"
mode.  These namespaces lack struct page and are prevented from
participating in filesystem DAX as of commit 569d0365f571 "dax: require
'struct page' by default for filesystem dax".

Signed-off-by: Ross Zwisler <ross.zwisler at linux.intel.com>
Suggested-by: Mike Snitzer <snitzer at redhat.com>
---
 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 68940356cad3..8b1fd7f1a224 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -414,7 +414,8 @@ static int pmem_attach_disk(struct device *dev,
 	blk_queue_logical_block_size(q, pmem_sector_size(ndns));
 	blk_queue_max_hw_sectors(q, UINT_MAX);
 	blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
-	blk_queue_flag_set(QUEUE_FLAG_DAX, q);
+	if (pmem->pfn_flags & PFN_MAP)
+		blk_queue_flag_set(QUEUE_FLAG_DAX, q);
 	q->queuedata = pmem;
 
 	disk = alloc_disk_node(0, nid);
-- 
2.14.4