We do not need two debug.h files.
Take Fujitsu's STATIC_ASSERT over BUILD_BUG_ON because it is more used
Change-Id: If04c17fbb7406ab15fe86267fed8d6da460cec62
Fujitsu: POSTK_DEBUG_ARCH_DEP_9
Hugetlbfs file mappings are handled differently than regular files:
- pager_req_create will tell us the file is in a hugetlbfs
- allocate memory upfront, we need to fail if not enough memory
- the memory needs to be given again if another process maps the same
file
This implementation still has some hacks, in particular, the memory
needs to be freed when all mappings are done and the file has been
deleted/closed by all processes.
We cannot know when the file is closed/unlinked easily, so clean up
memory when all processes have exited.
To test, install libhugetlbfs and link a program with the additional
LDFLAGS += -B /usr/share/libhugetlbfs -Wl,--hugetlbfs-align
Then run with HUGETLB_ELFMAP=RW set, you can check this works with
HUGETLB_DEBUG=1 HUGETLB_VERBOSE=2
Change-Id: I327920ff06efd82e91b319b27319f41912169af1