decompressors: add lz4 decompressor module

This patch adds support for LZ4 decompression in the kernel.
LZ4 Decompression APIs for kernel are based on LZ4 implementation
by Yann Collet.

LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html
LZ4 source repository : http://code.google.com/p/lz4/

Signed-off-by: Kyungsik Lee <kyungsik.lee@lge.com>
lib: add support for LZ4-compressed kernels

This patch adds support for extracting LZ4-compressed kernel images,
as well as LZ4-compressed ramdisk images in the kernel boot process.

This depends on the patch below
decompressors: add lz4 decompressor module

Signed-off-by: Kyungsik Lee <kyungsik.lee@lge.com>
arm: add support for LZ4-compressed kernels

This patch integrates the LZ4 decompression code to the arm pre-boot code.
And it depends on two patchs below

lib: add support for LZ4-compressed kernels
decompressors: add lz4 decompressor module

Signed-off-by: Kyungsik Lee <kyungsik.lee@lge.com>
ARM: 7583/1: decompressor: Enable unaligned memory access for v6 and above

Modern GCC can generate code which makes use of the CPU's native
unaligned memory access capabilities.  This is useful for the C
decompressor implementations used for unpacking compressed kernels.

This patch disables alignment faults and enables the v6 unaligned
access model on CPUs which support these features (i.e., v6 and
later), allowing full unaligned access support for C code in the
decompressor.

The decompressor C code must not be built to assume that unaligned
access works if support for v5 or older platforms is included in
the kernel.

For correct code generation, C decompressor code must always use
the get_unaligned and put_unaligned accessors when dealing with
unaligned pointers, regardless of this patch.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
arch/arm/Kconfig: enable unaligned capability for ARM

Signed-off-by: faux123 <reioux@gmail.com>
lib/lzo: Rename lzo1x_decompress.c to lzo1x_decompress_safe.c

Rename the source file to match the function name and thereby
also make room for a possible future even slightly faster
"non-safe" decompressor version.

Signed-off-by: Markus F.X.J. Oberhumer <markus@oberhumer.com>
kernel: Move REPEAT_BYTE definition into linux/kernel.h

And make sure that everything using it explicitly includes
that header file.

Signed-off-by: David S. Miller <davem@davemloft.net>
modified for Mako kernel from kernel.org

Signed-off-by: faux123 <reioux@gmail.com>
lib: Sparc's strncpy_from_user is generic enough, move under lib/

To use this, an architecture simply needs to:

1) Provide a user_addr_max() implementation via asm/uaccess.h

2) Add "select GENERIC_STRNCPY_FROM_USER" to their arch Kcnfig

3) Remove the existing strncpy_from_user() implementation and symbol
   exports their architecture had.

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: David Howells <dhowells@redhat.com>
adapted for Mako from kernel.org reference

Signed-off-by: faux123 <reioux@gmail.com>