lib: add weak clz/ctz functions

Some architectures need __c[lt]z[sd]i2() for __builtin_c[lt]z[ll] and It
causes build failure. They can be implemented using the fls()/__ffs()
and
overridden by linking arch-specific versions may not be implemented yet.
This is required by "lib: add lz4 compressor module".

Reference: https://lkml.org/lkml/2013/4/18/603
Signed-off-by: Chanho Min <chanho.min@lge.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: "Darrick J. Wong" <djwong@us.ibm.com>
Cc: Bob Pearson <rpearson@systemfabricworks.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Herbert Xu <herbert@gondor.hengli.com.au>
Cc: Yann Collet <yann.collet.73@gmail.com>
Cc: Kyungsik Lee <kyungsik.lee@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Modified by Locasto for 3.0.xx
Signed-off-by: Locasto <amperific@gmail.com>
decompressor: add LZ4 decompressor module & lib: add support for LZ4-compressed kernel

Add support for LZ4 decompression in the Linux Kernel. LZ4 Decompression
APIs for kernel are based on LZ4 implementation by Yann Collet.

Benchmark Results(PATCH v3)
Compiler: Linaro ARM gcc 4.6.2

1. ARMv7, 1.5GHz based board
 Kernel: linux 3.4
 Uncompressed Kernel Size: 14MB Compressed Size Decompression Speed

 LZO 6.7MB 20.1MB/s, 25.2MB/s(UA)
 LZ4 7.3MB 29.1MB/s, 45.6MB/s(UA)

2. ARMv7, 1.7GHz based board
 Kernel: linux 3.7
 Uncompressed Kernel Size: 14MB Compressed Size Decompression Speed

 LZO 6.0MB 34.1MB/s, 52.2MB/s(UA)
 LZ4 6.5MB 86.7MB/s
- UA: Unaligned memory Access support
- Latest patch set for LZO applied

This patch set is for adding support for LZ4-compressed Kernel. LZ4 is a
very fast lossless compression algorithm and it also features an
extremely
fast decoder [1].

But we have five of decompressors already and one question which does
arise, however, is that of where do we stop adding new ones? This issue
had been discussed and came to the conclusion [2].
Russell King said that we should have:

- one decompressor which is the fastest
- one decompressor for the highest compression ratio
- one popular decompressor (eg conventional gzip)

If we have a replacement one for one of these, then it should do exactly
that: replace it.

The benchmark shows that an 8% increase in image size vs a 66% increase
in
decompression speed compared to LZO(which has been known as the fastest
decompressor in the Kernel). Therefore the "fast but may not be small"
compression title has clearly been taken by LZ4 [3].
[1] http://code.google.com/p/lz4/
[2] http://thread.gmane.org/gmane.linux.kbuild.devel/9157
[3] http://thread.gmane.org/gmane.linux.kbuild.devel/9347

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>
Signed-off-by: Yann Collet <yann.collet.73@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Signed-off-by: Locasto <amperific@gmail.com>

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

Signed-off-by: Kyungsik Lee <kyungsik.lee@lge.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Florian Fainelli <florian@openwrt.org>
Cc: Yann Collet <yann.collet.73@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Modified by Amperific for 3.0.xx
Signed-off-by: Locasto <amperific@gmail.com>
kbuild: fix for updated LZ4 tool with the new streaming format

LZ4 has been updated with LZ4 Streaming Format specification(v1.3).
lz4demo is replaced by lz4c. lz4c supports both the new streaming and
legacy format with -l option. This patch makes use of lz4c to support
legacy format which is used for LZ4 De/compression in the linux kernel.

Link: https://code.google.com/p/lz4/source/checkout

Signed-off-by: Kyungsik Lee <kyungsik.lee@lge.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Florian Fainelli <florian@openwrt.org>
Cc: Yann Collet <yann.collet.73@gmail.com>
Cc: Chanho Min <chanho.min@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Signed-off-by: Locasto <amperific@gmail.com>
arm: add support for LZ4-compressed kernel

Integrates the LZ4 decompression code to the arm pre-boot code.

Signed-off-by: Kyungsik Lee <kyungsik.lee@lge.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Florian Fainelli <florian@openwrt.org>
Cc: Yann Collet <yann.collet.73@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Modified by ASKP for 3.0.xx
Signed-off-by: Locasto <amperific@gmail.com>
arm: Remove enforced Os flag for LZ4 decompressor

-Os is enforced here, based on the test result of decompression time
below, slightly faster than -O2. But further tests with UA show that
using -O2 will be the right choice especially in the case of the
unaligned access enabled and the gap, few counts in the normal
decompression mode is small enough to remove -Os. Decompression
Time(counts) Normal UA enabled -Os 6717 3447 -O2 6720 2728 Note: ARM
v7, Kernel 3.4 counter freq. = 32768 HZ UA(Unaligned Access) gcc
version 4.6.2

Signed-off-by: Kyungsik Lee <kyungsik.lee@lge.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Florian Fainelli <florian@openwrt.org>
Cc: Yann Collet <yann.collet.73@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Signed-off-by: Locasto <amperific@gmail.com>
lib: add lz4 compressor module

This patchset is for supporting LZ4 compression and the crypto API
using it. As shown below, the size of data is a little bit bigger but
compressing speed is faster under the enabled unaligned memory access.
We can use lz4 de/compression through crypto API as well. Also, It will
be useful for another potential user of lz4 compression. lz4
Compression Benchmark: Compiler: ARM gcc 4.6.4 ARMv7, 1 GHz based board
Kernel: linux 3.4 Uncompressed data Size: 101 MB Compressed Size
compression Speed LZO 72.1MB 32.1MB/s, 33.0MB/s(UA) LZ4 75.1MB
30.4MB/s, 35.9MB/s(UA) LZ4HC 59.8MB 2.4MB/s, 2.5MB/s(UA) - UA:
Unaligned memory Access support - Latest patch set for LZO applied This
patch: Add support for LZ4 compression in the Linux Kernel. LZ4
Compression APIs for kernel are based on LZ4 implementation by Yann
Collet and were changed for kernel coding style. LZ4 homepage :
http://fastcompression.blogspot.com/p/lz4.html LZ4 source repository :
http://code.google.com/p/lz4/ svn revision : r90 Two APIs are added:
lz4_compress() support basic lz4 compression whereas lz4hc_compress()
support high compression or CPU performance get lower but compression
ratio get higher. Also, we require the pre-allocated working memory
with the defined size and destination buffer must be allocated with the
size of lz4_compressbound. Signed-off-by: Chanho Min
<chanho.min@lge.com> Cc: "Darrick J. Wong" <djwong@us.ibm.com> Cc: Bob
Pearson <rpearson@systemfabricworks.com> Cc: Richard Weinberger
<richard@nod.at> Cc: Herbert Xu <herbert@gondor.hengli.com.au> Cc: Yann
Collet <yann.collet.73@gmail.com> Cc: Kyungsik Lee
<kyungsik.lee@lge.com> Signed-off-by: Andrew Morton
<akpm@linux-foundation.org>

Signed-off-by: Locasto <amperific@gmail.com>
lib-add-lz4-compressor-module-fix

make lz4_compresshcctx() static

Cc: Chanho Min <chanho.min@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Signed-off-by: Locasto <amperific@gmail.com>
crypto: add lz4 Cryptographic API

Add support for lz4 and lz4hc compression algorithm using the lib/lz4/*
codebase.

Modified by ASKP for 3.0.xx
Signed-off-by: Locasto <amperific@gmail.com>
crypto-add-lz4-cryptographic-api-fix

fix warnings

Signed-off-by: Locasto <amperific@gmail.com>
mm: memory_hotplug: Coming from 3.9

Signed-off-by: Amperific <amperific@gmail.com>