On 24.01.23 21:34, Jason Gunthorpe wrote:
Move the flags that should not/are not used outside gup.c and related into mm/internal.h to discourage driver abuse. To make this more maintainable going forward compact the two FOLL ranges with new bit numbers from 0 to 11 and 16 to 21, using shifts so it is explict. Switch to an enum so the whole thing is easier to read.
Using a __bitwise type would be even better, but that requires quite some adjustments ...
The primary leftover for FOLL_GET seems to be follow_page(). IIRC, there is only one caller that doesn't pass FOLL_GET (s390). We could either add a new function to "probe" that anything is mapped (IIRC that's the use case), or simply ref+unref.
So we might just be able to make FOLL_GET internal fairly easily, too ... Anyhow Acked-by: David Hildenbrand <david@xxxxxxxxxx> -- Thanks, David / dhildenb
