You already have both __KERNEL__ and user space parts in your header.
Function declarations clearly don't belong in the user visible parts.
I suggest you only leave on-disk data structure definitions and user
interfaces in the user-visible include/linux/axfs.h file, and move
all internal interfaces to fs/axfs/axfs.h.
For on-disk data structures, I would use __be64 or __le64 types,
preferrably the opposite of your native CPU byte order on the system
you are developing most code on, to make sure that you get endianess
right.
What happens on systems where AXFS_PAGE_SIZE != PAGE_SIZE?
These are already defined in <linux/kernel.h>, so please use the
existing definitions.
Arnd <><
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