This patch series are intended to test the POWER9 Nest Accelerator (NX) GZIP engine that is being introduced by https://lists.ozlabs.org/pipermail/linuxppc-dev/2020-March/205659.html More information about how to access the NX can be found in that patch, also a complete userspace library and more documentation can be found at: https://github.com/libnxz/power-gzip Changes in V3: - Defined a macro and increased the number of retries for page faults to work in system with less memory, mentioning the issue on README. - Returned to use volatile on the touch pages routine and a few structs on inc/nxu.h as they are handled by hardware and some compilers could optmize it wrongly. - Moved common functions to gzip_vas.c.
