Prepare for removing num_physpages and simplify mem_init(). Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: David Daney <david.daney@cavium.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Jiri Kosina <jkosina@suse.cz> Cc: John Crispin <blogic@openwrt.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>