On Thu, Jul 13, 2023 at 01:04:39AM -0400, Kent Overstreet wrote: > On Mon, Jul 10, 2023 at 02:02:51PM +0100, Matthew Wilcox (Oracle) wrote: > > Allow callers of __filemap_get_folio() to specify a preferred folio > > order in the FGP flags. This is only honoured in the FGP_CREATE path; > > if there is already a folio in the page cache that covers the index, > > we will return it, no matter what its order is. No create-around is > > attempted; we will only create folios which start at the specified index. > > Unmodified callers will continue to allocate order 0 folios. > > Why not just add an end_index parameter to filemap_get_folio()? I'm reluctant to add more parameters. Aside from the churn, every extra parameter makes the function that little bit harder to use. I like this encoding; users who don't know/care about it get the current default behaviour, and it's a simple addition to the users who do want to care. end_index is particularly tricky ... what if it's lower than index?