[RFC PATCH 1/3] powerpc: Add support for multiple PTE page fragment in PTE page

[Aneesh Kumar K.V]

Hello,

This is the preparatory patchset for supporting THP on powerpc. I am sending this across
so that we can get review on this change.


For full THP support on powerpc, I have an early version that boots and runs few test. But
I am still running into few issues, like Firmware NMI etc. Once those are resolved, I will
clean them up and send the complete patchset. 

IMHO we should NOT be merging this patchset until we have the full THP patchset on the list.
But still it will be nice to get review on the multiple PTE page fragment change. Other
architectures like s390 and sparc do support something similar. The implementation here
closely follows the s390 implementation.


-aneesh