On Sat, Jul 17, 2021 at 07:40:41PM +0100, Matthew Wilcox wrote: > Well, either sense of a WARN_ON is wrong. > > For a file which is PAGE_SIZE + 3 bytes in size, to_iomap_page() will > be NULL. For a file which is PAGE_SIZE/2 + 3 bytes in size, > to_iomap_page() will not be NULL. (assuming the block size is <= > PAGE_SIZE / 2). > > I think we need a prep patch that looks something like this: Something like this is where we should eventually end up, but it also affects the read from disk case so we need to be careful.
