Filesystem-DAX flushes caches whenever it writes to the address returned
through dax_direct_access() and when writing back dirty radix entries.
That flushing is only required in the pmem case, so the dax_flush()
helper skips cache management work when the underlying driver does not
specify a flush method.
We still do all the dirty tracking since the radix entry will already be
there for locking purposes. However, the work to clean the entry will be
a nop for some dax drivers.
Cc: Jan Kara <j...@suse.cz>
Cc: Jeff Moyer <jmo...@redhat.com>
Cc: Christoph Hellwig <h...@lst.de>
Cc: Matthew Wilcox <mawil...@microsoft.com>
Cc: Ross Zwisler <ross.zwis...@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.willi...@intel.com>
---
fs/dax.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/dax.c b/fs/dax.c
index 11b9909c91df..edbf988de86c 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -798,7 +798,7 @@ static int dax_writeback_one(struct block_device *bdev,
}
dax_mapping_entry_mkclean(mapping, index, pfn_t_to_pfn(pfn));
- wb_cache_pmem(kaddr, size);
+ dax_flush(dax_dev, pgoff, kaddr, size);
/*
* After we have flushed the cache, we can clear the dirty tag. There
* cannot be new dirty data in the pfn after the flush has completed as
