elf_core_dump() and elf_fdpic_core_dump() use #ifdef and the corresponding
macro for hiding _multiline_ logics in functions.  This patch removes
#ifdef and replaces ELF_CORE_EXTRA_* by corresponding functions.  For
architectures not implemeonting ELF_CORE_EXTRA_*, we use weak functions in
order to reduce a range of modification.

This cleanup is for my next patches, but I think this cleanup itself is
worth doing regardless of my firnal purpose.

Signed-off-by: Daisuke HATAYAMA <d.hatayama@jp.fujitsu.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Greg Ungerer <gerg@snapgear.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This adds fs/compat_binfmt_elf.c, a wrapper around fs/binfmt_elf.c for
32-bit ELF support on 64-bit kernels.  It can replace all the hand-rolled
versions of this that each 32/64 arch has, which are all about the same.

To use this, an arch's asm/elf.h has to define at least a few compat_*
macros that parallel the various macros that fs/binfmt_elf.c uses for
native support.

There is no attempt to deal with compat macros for the core dump format
support.  To use this file, the arch has to define compat_gregset_t for
linux/elfcore-compat.h and #define CORE_DUMP_USE_REGSET.  The 32-bit
compatible formats should come automatically from task_user_regset_view
called on a 32-bit task.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>