Backport several fixes from 64bits to 32bits hibernation

Currently there are mainly three bugs in 32bits system when doing hibernation:
1. The page copy code is not running in safe page, which might cause hang during resume.
2. There's no text mapping for the final jump address
of the original kernel, which might cause the system jumping into illegal address and causes system hang during resume.
3. The restore kernel switches to its own kernel page table(swapper_pg_dir) rather than the original kernel page table after all the pages been copied back, which might cause invalid virtual-physical mapping issue during resume.

To solve these problems:

1. Copy the code core_restore_code to a safe page, to avoid the instruction code been overwritten when image kernel pages are being copied.
2. Set up temporary text mapping for the image kernel's jump address, so that after all the pages have been copied back, the system could jump to this address.
3. Switch to the original kernel page table during resume.

Furthermore, MD5 hash check for e820 map is also backported from 64bits system.

In order to make this patch set more readable, these fixes are splitted into several sub patches.

And use CONFIG_X86_64 to control the common code to be 'activated' for 32 bit system during each sub-patch for better maintaining.

Chen Yu (1):
PM / hibernate: Check the success of generating md5 digest before
hibernation

Zhimin Gu (11):
x86, hibernate: Fix nosave_regions setup for hibernation x86-32/asm/power: Create stack frames in hibernate_asm_32.S x86, hibernate: Extract the common code of 64/32 bit system x86-32, hibernate: Enable CONFIG_ARCH_HIBERNATION_HEADER on 32bit
system
x86, hibernate: Rename temp_level4_pgt to temp_pgt x86-32, hibernate: Use temp_pgt as the temporary page table x86-32, hibernate: Use the page size macro instead of constant value x86-32, hibernate: Switch to original page table after resumed x86-32, hibernate: Switch to relocated restore code during resume on
32bit system
x86-32, hibernate: Set up temporary text mapping for 32bit system x86-32, hibernate: Adjust in_suspend after resumed on 32bit system

 arch/x86/Kconfig                  |   2 +-
 arch/x86/include/asm/suspend.h    |   8 +
 arch/x86/include/asm/suspend_32.h |   4 +
 arch/x86/kernel/setup.c           |   2 +-
 arch/x86/power/Makefile           |   2 +-
 arch/x86/power/hibernate.c        | 248 ++++++++++++++++++++++++++++++
 arch/x86/power/hibernate_32.c     |  52 +++++--
 arch/x86/power/hibernate_64.c     | 224 +--------------------------
 arch/x86/power/hibernate_asm_32.S |  37 ++++-
 arch/x86/power/hibernate_asm_64.S |   2 +-
 10 files changed, 334 insertions(+), 247 deletions(-)
 create mode 100644 arch/x86/power/hibernate.c

2.17.1