On Fri 09-06-17 13:24:18, Dan Williams wrote:
> 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>
Looks good to me. You can add:
Reviewed-by: Jan Kara <j...@suse.cz>
Honza
> ---
> fs/dax.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/dax.c b/fs/dax.c
> index b459948de427..0933fc460ada 100644
> --- a/fs/dax.c
> +++ b/fs/dax.c
> @@ -784,7 +784,7 @@ 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
>
--
Jan Kara <j...@suse.com>
SUSE Labs, CR
