Maze of include files, all producing errors...

In 2.5.5 (Changeset 1.359.2.3), the highmem.h and pgalloc.h includes were reversed.

Previous kernels had linux/highmem.h including asm/pgalloc.h. Placing the architecture cache handling functions worked well in asm/pgalloc.h, allowing highmem.h to find them; highmem.h uses flush_dcache_page() and friends in inline functions.

In this changeset, highmem.h no longer includes pgalloc.h, but instead pgalloc.h includes highmem.h. This, unfortunately, tends to break things in a major way since the cache functions are no longer available to highmem.h.

Looking at x86, the (no-op) cache functions live in pgtable.h. However, trying to put the ARM cache handling into pgtable.h doesn't work because we need things like PG_arch_1 and struct page. pgtable.h is included by linux/mm.h before linux/mm.h declares PG_arch_1 and struct page. So obviously this can't work.

Has anyone encountered this, and has anyone found a magic working combination?

For now, I'm going to reverse the include changes in this changeset so things build again.

Russell King ([email protected])                The developer of ARM Linux
             http://www.arm.linux.org.uk/personal/aboutme.html

That's what I did for alpha too.

r~

I've noticed it's a mess...

I ran into a different problem yesterday. It seems mmzone.h is included before struct page is defined and therefore inlines in mmzone.h can't do arithmetic on the size of struct page. This forces code in mmzone.h to be macros instead of inlines.

Daniel