On Sat, 22 Aug 2020 01:12:09 +1000 Nicholas Piggin <npiggin@xxxxxxxxx> wrote: > This changes the awkward approach where architectures provide init > functions to determine which levels they can provide large mappings for, > to one where the arch is queried for each call. > > This removes code and indirection, and allows constant-folding of dead > code for unsupported levels. > > This also adds a prot argument to the arch query. This is unused > currently but could help with some architectures (e.g., some powerpc > processors can't map uncacheable memory with large pages). > > --- a/arch/arm64/include/asm/vmalloc.h > +++ b/arch/arm64/include/asm/vmalloc.h > @@ -1,4 +1,12 @@ > #ifndef _ASM_ARM64_VMALLOC_H > #define _ASM_ARM64_VMALLOC_H > > +#include <asm/page.h> > + > +#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP > +bool arch_vmap_p4d_supported(pgprot_t prot); > +bool arch_vmap_pud_supported(pgprot_t prot); > +bool arch_vmap_pmd_supported(pgprot_t prot); > +#endif Moving these out of generic code and into multiple arch headers is unfortunate. Can we leave them in include/linux/somewhere? And remove the ifdefs, if so inclined - they just move the build error from link-time to compile-time, and such an error shouldn't occur!