On Wed, Nov 10, 2021 at 03:52:01PM +0100, Andreas Gruenbacher wrote: > Hmm, that doesn't make sense to me: the filesystem doesn't know that > iomap_readpage will pad to page boundaries. This happens at the iomap > layer, so the iomap layer should also deal with the consequences. > We're using different alignment rules here and for direct I/O, so that > makes fake-aligning the extent size in iomap_begin even more > questionable. > > "Fixing" the extent size the filesystem returns would also break > direct I/O. We could add some additional padding code to > iomap_dio_inline_iter to deal with that, but currently, there's no > need for that.
The iomap mapping sizes are read-only to iomap for a good reason. You can't just break that design.
