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If so, please > > > > > let me know; some example would be greatly helpful. > > > > > > > > Just document the 'VA % order = pgoff % order' equation in the kdoc > > > > for the new op. > > > > > > When it's "related to PTEs", it's talking about (2) above, so that's really > > > what I want to avoid mentioning. > > > > You can't avoid it. Drivers must ensure that > > > > pgoff % order == physical % order > > > > And that is something only drivers can do by knowing about this > > requirement. > > This is a current limitation that above must be guaranteed, there's not > much the driver can do, IMHO. There is alot the driver can do! The driver decides on the pgoff values it is using, it needs to keep the above in mind when it builds its pgoff number space! > If you could remember, that's the only reason why I used to suggest (while > we were discussing this in v1) to make it *pgoff instead of pgoff, so that > drivers can change *pgoff to make it relevant to HPA. What? That's nonsense. The pgoff space is assigned by the driver and needs to remain a fixed relationship to the underlying phys the driver is mapping in. It shouldn't be changing pgoff during mmap! Jason