arm, arm64: move free_unused_memmap() to generic mm

ARM and ARM64 free unused parts of the memory map just before the
initialization of the page allocator. To allow holes in the memory map both
architectures overload pfn_valid() and define HAVE_ARCH_PFN_VALID.

Allowing holes in the memory map for FLATMEM may be useful for small
machines, such as ARC and m68k and will enable those architectures to cease
using DISCONTIGMEM and still support more than one memory bank.

Move the functions that free unused memory map to generic mm and enable
them in case HAVE_ARCH_PFN_VALID=y.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Mike Rapoport <[email protected]>
Acked-by: Catalin Marinas <[email protected]>	[arm64]
Cc: Alexey Dobriyan <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Greg Ungerer <[email protected]>
Cc: John Paul Adrian Glaubitz <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Matt Turner <[email protected]>
Cc: Meelis Roos <[email protected]>
Cc: Michael Schmitz <[email protected]>
Cc: Russell King <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: Vineet Gupta <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions