dax: remove default copy_from_iter fallback
Require all dax-drivers to register a ->copy_from_iter() operation so
that it is clear which dax_operations are optional and which must be
implemented for filesystem-dax to operate.
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/include/linux/dax.h b/include/linux/dax.h
index 1f6b607..73fca1b 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -16,7 +16,7 @@
*/
long (*direct_access)(struct dax_device *, pgoff_t, long,
void **, pfn_t *);
- /* copy_from_iter: dax-driver override for default copy_from_iter */
+ /* copy_from_iter: required operation for fs-dax direct-i/o */
size_t (*copy_from_iter)(struct dax_device *, pgoff_t, void *, size_t,
struct iov_iter *);
/* flush: optional driver-specific cache management after writes */