On Mon, Nov 07, 2016 at 02:13:05PM +0300, Kirill A. Shutemov wrote: > It looks like a huge limitation to me.
The DAX PMD fault code can live just fine with it. And without it performance would suck anyway. > I'm looking onto iomap_write_actor(): we still calculate 'offset' and > 'bytes' based on PAGE_SIZE before we even get the page. > This way we limit outself to PAGE_SIZE per-iteration. Of course it does, given that it does not support huge pages _yet_. But the important part is that this is now isolate to the highlevel code, and the fs can get iomap_begin calls for a huge page (or in fact much larger sizes than that).
