On Mon, Aug 24, 2020 at 03:55:07PM +0100, Matthew Wilcox (Oracle) wrote: > Instead of counting bio segments, count the number of bytes submitted. > This insulates us from the block layer's definition of what a 'same page' > is, which is not necessarily clear once THPs are involved. I'd like to see a comment on the definition of struct iomap_page to indicate that read_count (and write count) reflect the byte count of IO currently in flight on the page, not an IO count, because THP makes tracking this via bio state hard. Otherwise it is not at all obvious why it is done and why it is intentional... Otherwise the code looks OK. Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx
