On Thu, Dec 02, 2021 at 04:48:52PM +0800, Shiyang Ruan wrote:

The current dax_lock_page() locks dax entry by obtaining mapping and
index in page.  To support 1-to-N RMAP in NVDIMM, we need a new function
to lock a specific dax entry corresponding to this file's mapping,index.
And BTW, output the page corresponding to the specific dax entry for
caller use.

s/BTW, //g

 /*
- * dax_lock_mapping_entry - Lock the DAX entry corresponding to a page
+ * dax_lock_page - Lock the DAX entry corresponding to a page
  * @page: The page whose entry we want to lock
  *
  * Context: Process context.

This should probably got into a separate trivial fix.

Otherwise looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>