On 03/09/2016 04:10 AM, Anshuman Khandual wrote:

Currently the 'huge_pte_offset' function has only one version for
all the configuations and platforms. This change splits the function
into two versions, one for 64K page size based BOOK3S implementation
and the other one for everything else. This change is also one of the
prerequisites towards enabling GENERAL_HUGETLB implementation for
BOOK3S 64K based huge pages.

I think there's a bit of background missing here for random folks on
linux-mm to make sense of these patches.

What is BOOK3S and what does it mean for these patches?  Why is its 64K
page size implementation different than all the others?  Is there a 4K
page size BOOK3S?