On Tue, Sep 21, 2021 at 09:34:55AM +0100, Christoph Hellwig wrote: > On Fri, Sep 17, 2021 at 06:30:50PM -0700, Darrick J. Wong wrote: > > + case IOMAP_MAPPED: > > + while (nr_pages > 0) { > > + /* XXX function only supports one page at a time?! */ > > + ret = dax_zero_page_range(iomap->dax_dev, start_page, > > + 1); > > Yes. Given that it will have to kmap every page that kinda makes sense. > Unlike a nr_pages argument which needs to be 1, which is just silly. > That being said it would make sense to move the trivial loop over the > pages into the methods to reduce the indirect function call overhead Done. AFAICT all the implementations *except* nvdimm can handle more than one page. --D