On Thu, Feb 14, 2019 at 04:30:04PM +0300, Kirill A. Shutemov wrote: > On Tue, Feb 12, 2019 at 10:34:54AM -0800, Matthew Wilcox wrote: > > Transparent Huge Pages are currently stored in i_pages as pointers to > > consecutive subpages. This patch changes that to storing consecutive > > pointers to the head page in preparation for storing huge pages more > > efficiently in i_pages. > > > > Large parts of this are "inspired" by Kirill's patch > > https://lore.kernel.org/lkml/20170126115819.58875-2-kirill.shutemov@xxxxxxxxxxxxxxx/ > > > > Signed-off-by: Matthew Wilcox <willy@xxxxxxxxxxxxx> > > I believe I found few missing pieces: > > - page_cache_delete_batch() will blow up on > > VM_BUG_ON_PAGE(page->index + HPAGE_PMD_NR - tail_pages > != pvec->pages[i]->index, page); > > - migrate_page_move_mapping() has to be converted too. Other missing pieces are memfd_wait_for_pins() and memfd_tag_pins() We need to call page_mapcount() for tail pages there. -- Kirill A. Shutemov
