On Fri, May 31, 2024 at 07:05:38AM -0700, Christoph Hellwig wrote: > On Fri, May 31, 2024 at 07:03:58AM -0700, Darrick J. Wong wrote: > > > + /* > > > + * XXX: It would be nice if we could get the offset of > > > + * the next entry in the pagecache so that we don't have > > > + * to iterate one page at a time here. > > > + */ > > > + offset = offset_in_page(pos); > > > + if (bytes > PAGE_SIZE - offset) > > > + bytes = PAGE_SIZE - offset; > > > > Why is it PAGE_SIZE here and not folio_size() like below? > > > > (I know you're just copying the existing code; I'm merely wondering if > > this is some minor bug.) > > See the comment just above :) > > FWIW, something like the following is pretty slow with the current implementation on a quick test: xfs_io -fc "falloc -k 0 1t" -c "pwrite 1000g 4k" <file> ... so I'd think you'd want some kind of data seek or something to more efficiently process the range. Brian
