well, in case of the PG_arch_* flags, they are all defined in
architecture files:
./include/asm-parisc/pgtable.h:#define PG_dcache_dirty PG_arch_1
./include/asm-mips/cacheflush.h:#define PG_dcache_dirty PG_arch_1
./arch/sparc64/mm/init.c:#define PG_dcache_dirty PG_arch_1
./arch/sh/include/cpu-sh4/cpu/cacheflush.h:#define PG_mapped PG_arch_1
./arch/sh/include/cpu-sh3/cpu/cacheflush.h:#define PG_mapped PG_arch_1
./arch/arm/include/asm/cacheflush.h:#define PG_dcache_dirty PG_arch_1
they are explicitly reserved for per architecture details.
Ingo
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